Thomas Kenny
Senior Associate Dean for Education and Student Affairs and Richard W. Weiland Professor in the School of Engineering
Mechanical Engineering
Bio
Kenny's group is researching fundamental issues and applications of micromechanical structures. These devices are usually fabricated from silicon wafers using integrated circuit fabrication tools. Using these techniques, the group builds sensitive accelerometers, infrared detectors, and force-sensing cantilevers. This research has many applications, including integrated packaging, inertial navigation, fundamental force measurements, experiments on bio-molecules, device cooling, bio-analytical instruments, and small robots. Because this research field is multidisciplinary in nature, work in this group is characterized by strong collaborations with other departments, as well as with local industry.
Administrative Appointments
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Senior Associate Dean of Engineering for Education and Student Affairs, School of Engineering (2015 - Present)
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The Paul Davies Family University Fellow in Undergraduate Education, Bass Foundation Fellow (2019 - 2024)
Honors & Awards
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Member, National Academy of Engineering (2022-)
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President's Award for Excellence through Diversity, Stanford University (2019)
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Tau Beta Pi Teaching Honor Roll, Tau Beta Pi (2019)
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Daniel Noble Award for Emerging Technologies, IEEE (2018)
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General Chair, Transducers 2015 (2015)
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Technical Achievement Award, IEEE (2011)
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Secretary of Defense Award for Exceptional Public Service, US Department of Defense (2010)
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Program Manager, DARPA Microsystems Technology Office (2006-2010)
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Captain, Ultimate Frisbee Coed World Champions (RFBF) (1999)
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Captain, Ultimate Frisbee Coed National Champions (RFBF) (1998)
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CAREER Award, NSF (1995-1999)
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Robert Bosch Faculty Scholar, Robert Bosch Foundation (1995-1999)
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Terman Fellowship, Stanford University (1995-1998)
Boards, Advisory Committees, Professional Organizations
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CEO Founder and Board Member, Applaud Medical (2020 - 2022)
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President, Transducers Research Foundation (2016 - Present)
Program Affiliations
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Stanford SystemX Alliance
Professional Education
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PhD, UC Berkeley, Physics (1989)
Patents
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Robert Grubbs, Marshall Stoller, Hoyong Chung, Alissa Fitzgerald, Thomas Kenny, Renee Thomas. "United States Patent 10,149,906 Targeting Microbubbles", Caltech, Dec 10, 2018
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Thomas Kenny, Mark Munch, Peng Zhou, James Gill Shook, Kenneth Goodson, Dave Corbin, Mark McMaster, James Lovette. "United States Patent US 8,464,781 Cooling Systems Incorporating Heat Exchangers and Thermoelectric Layers", Cooligy, Inc, Jul 18, 2013
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Robert J. Full, Ronald S. Fearing, Thomas W. Kenny, Kellar Autumn. "United States Patent US 6,737,160 Adhesive Microstructure and Method of Forming Same", The Regents Of The University Of California, May 18, 0004
2024-25 Courses
- Develop Your Leadership Toolkit: Aim High, Embrace Uncertainty, and Achieve Impact
ENGR 193 (Spr) - Introduction to Mechatronics
EE 118, ME 210 (Win) - Introduction to Sensors
ME 220 (Spr) - Want to Be an Engineer?
ENGR 1 (Aut) -
Independent Studies (16)
- Curricular Practical Training
APPPHYS 291 (Aut, Win, Spr) - Directed Research and Writing in Aero/Astro
AA 190 (Aut, Win, Spr) - Directed Studies in Applied Physics
APPPHYS 290 (Aut, Win, Spr) - Engineering Problems
ME 391 (Aut, Win, Spr) - Engineering Problems and Experimental Investigation
ME 191 (Aut, Win, Spr) - Experimental Investigation of Engineering Problems
ME 392 (Aut, Win, Spr) - Honors Research
ME 191H (Aut, Win, Spr) - Independent Study in Aero/Astro
AA 199 (Aut, Win, Spr) - Master's Directed Research
ME 393 (Aut, Win, Spr) - Master's Directed Research: Writing the Report
ME 393W (Aut, Win, Spr) - Ph.D. Research Rotation
ME 398 (Aut, Win, Spr) - Ph.D. Teaching Experience
ME 491 (Aut, Win, Spr) - Practical Training
ME 199A (Win, Spr) - Practical Training
ME 299A (Aut, Win, Spr) - Practical Training
ME 299B (Aut, Win, Spr) - Writing of Original Research for Engineers
ENGR 199W (Aut, Win, Spr)
- Curricular Practical Training
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Prior Year Courses
2023-24 Courses
- Discover Engineering: How to Aim High, Embrace Uncertainty, and Achieve Impact
ENGR 193 (Spr) - Introduction to Mechatronics
EE 118, ME 210 (Win) - Introduction to Sensors
ME 220 (Spr)
2022-23 Courses
- Discover Engineering: How to Aim High, Embrace Uncertainty, and Achieve Impact
ENGR 193 (Spr) - Introduction to Mechatronics
ME 210 (Win) - Introduction to Sensors
ME 220 (Spr) - Want to Be an Engineer?
ENGR 1 (Aut)
2021-22 Courses
- Discover Engineering: How to Aim High, Embrace Uncertainty, and Achieve Impact
ENGR 193 (Spr) - Introduction to Mechatronics
ME 210 (Win) - Introduction to Sensors
ME 220 (Spr) - Want to Be an Engineer?
ENGR 1 (Aut)
- Discover Engineering: How to Aim High, Embrace Uncertainty, and Achieve Impact
Stanford Advisees
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Doctoral Dissertation Reader (AC)
Sri Lingamneni -
Master's Program Advisor
Qianzhong Chen, Dolly Mantle, Allison Tsai -
Doctoral Dissertation Co-Advisor (AC)
L'Nard Tufts -
Doctoral (Program)
Ruixin Qiu
All Publications
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A temperature compensated biaxial eFM accelerometer in Epi-seal process
SENSORS AND ACTUATORS A-PHYSICAL
2021; 330
View details for DOI 10.1016/j.sna.2021.112860
View details for Web of Science ID 000669229900010
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Amplitude stabilization of micromechanical oscillators using engineered nonlinearity
PHYSICAL REVIEW RESEARCH
2021; 3 (3)
View details for DOI 10.1103/PhysRevResearch.3.033268
View details for Web of Science ID 000705661700005
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Nonlinear Dissipation in Epitaxial SCS and Polysilicon MEMS Driven at Large Amplitudes (vol 29, pg 1118, 2020)
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2021; 30 (2): 330
View details for DOI 10.1109/JMEMS.2021.3062697
View details for Web of Science ID 000638400700019
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Quantification of Energy Dissipation Mechanisms in Toroidal Ring Gyroscope
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2021; 30 (2): 193–202
View details for DOI 10.1109/JMEMS.2020.3045985
View details for Web of Science ID 000638400700004
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A Novel Spring Disk Resonator Gyroscope for Maximizing Q/F
IEEE. 2021
View details for DOI 10.1109/INERTIAL51137.2021.9430453
View details for Web of Science ID 000680838400001
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Bicontinuous Mesoporous Metal Foams with Enhanced Conductivity and Tunable Pore Size and Porosity via Electrodeposition for Electrochemical and Thermal Systems
ACS APPLIED NANO MATERIALS
2020; 3 (12): 12408–15
View details for DOI 10.1021/acsanm.0c02970
View details for Web of Science ID 000603402500078
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Negative Nonlinear Dissipation in Microelectromechanical Beams (vol 29, pg 1, 2020)
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2020; 29 (6): 1582
View details for DOI 10.1109/JMEMS.2020.3010425
View details for Web of Science ID 000595526700022
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Characterization of Accelerated Fatigue in Thick Epi-Polysilicon Vacuum Encapsulated MEMS Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2020; 29 (6): 1483–92
View details for DOI 10.1109/JMEMS.2020.3021947
View details for Web of Science ID 000595526700010
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Numerical Modelling of Non-Linearities in MEMS Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2020; 29 (6): 1443–54
View details for DOI 10.1109/JMEMS.2020.3026085
View details for Web of Science ID 000595526700006
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Nonlinear Dissipation in Epitaxial SCS and Polysilicon MEMS Driven at Large Amplitudes
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2020; 29 (5): 1118–20
View details for DOI 10.1109/JMEMS.2020.3005323
View details for Web of Science ID 000576466500084
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Anchor Design Affects Dominant Energy Loss Mechanism in a Lame Mode MEM Resonator
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2020; 29 (5): 860–66
View details for DOI 10.1109/JMEMS.2020.3012925
View details for Web of Science ID 000576466500035
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Limits to Thermal-Piezoresistive Cooling in Silicon Micromechanical Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2020; 29 (5): 677–84
View details for DOI 10.1109/JMEMS.2020.3022050
View details for Web of Science ID 000576466500009
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Quality Factor Extraction and Enhancement Across Temperature in Ring Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2020; 29 (5): 1124–26
View details for DOI 10.1109/JMEMS.2020.3004748
View details for Web of Science ID 000576466500086
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Negative Nonlinear Dissipation in Microelectromechanical Beams
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2020; 29 (5): 954–59
View details for DOI 10.1109/JMEMS.2020.3006800
View details for Web of Science ID 000576466500050
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Crystal Orientation Dependent Dual Frequency Ovenized MEMS Resonator With Temperature Stability and Shock Robustness
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. 2020: 1130–31
View details for DOI 10.1109/JMEMS.2020.3012109
View details for Web of Science ID 000576466500088
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On the effect of linear feedback and parametric pumping on a resonator's frequency stability
NEW JOURNAL OF PHYSICS
2020; 22 (9)
View details for DOI 10.1088/1367-2630/abb1dd
View details for Web of Science ID 000575215400001
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Spectral narrowing of parametrically pumped thermomechanical noise
APPLIED PHYSICS LETTERS
2020; 117 (3)
View details for DOI 10.1063/5.0009848
View details for Web of Science ID 000554946500002
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Low-Power Dual Mode MEMS Resonators With PPB Stability Over Temperature
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. 2020: 190–201
View details for DOI 10.1109/JMEMS.2020.2970609
View details for Web of Science ID 000524501600009
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Quality factor tuning of micromechanical resonators via electrical dissipation
APPLIED PHYSICS LETTERS
2020; 116 (2)
View details for DOI 10.1063/1.5125286
View details for Web of Science ID 000518030500007
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AN EPI-SEAL ENCAPSULATED FRANKLIN OSCILLATOR SUSTAINING MORE THAN 200,000,000 ELECTRIC SWITCHING CYCLES
IEEE. 2020: 230–33
View details for Web of Science ID 000569381600058
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Thermal Accelerometer Performance Enhancements through AC Biasing Schemes
IEEE. 2020
View details for Web of Science ID 000582416900025
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Design Comparison and Survivability of Fipitaxially hncapsulated MFMS Disc Resonating Gyroscopes at High Shock (> 27,000g)
IEEE. 2020
View details for Web of Science ID 000582416900015
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THERMAL STABILITY OF DETF MEMS RESONATORS: NUMERICAL MODELLING AND EXPERIMENTAL VALIDATION
IEEE. 2020: 1207–10
View details for Web of Science ID 000569381600312
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REQUENCY STABILIZATION IN AN ENCAPSULATED HIGH-Q MICROMECHANICAL RESONATOR VIA INTERNAL RESONANCE
IEEE. 2020: 1191–94
View details for Web of Science ID 000569381600308
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TEMPERATURE HYSTERESIS IN PIEZORESISTIVE MICROCANTILEVERS
IEEE. 2020: 1203–6
View details for Web of Science ID 000569381600311
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NONLINEAR MODAL INTERACTIONS AND INTERNAL RESONANCE IN A MICROMACHINED DISK RESONATOR
IEEE. 2020: 769–72
View details for Web of Science ID 000569381600199
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Thermomechanical-Noise-Limited Capacitive Transduction of Encapsulated MEM Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2019; 28 (6): 965–76
View details for DOI 10.1109/JMEMS.2019.2936843
View details for Web of Science ID 000501826900004
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Phase Control of Self-Excited Parametric Resonators
PHYSICAL REVIEW APPLIED
2019; 12 (4)
View details for DOI 10.1103/PhysRevApplied.12.044053
View details for Web of Science ID 000492000500003
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Micro-Tethering for Fabrication of Encapsulated Inertial Sensors With High Sensitivity
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2019; 28 (3): 372–81
View details for DOI 10.1109/JMEMS.2019.2900761
View details for Web of Science ID 000470838300007
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Electrical Properties of Ultrathin Platinum Films by Plasma-Enhanced Atomic Layer Deposition
ACS APPLIED MATERIALS & INTERFACES
2019; 11 (9): 9594–99
Abstract
The ability to deposit thin and conformal films has become of great importance because of downscaling of devices. However, because of nucleation difficulty, depositing an electrically stable and thin conformal platinum film on an oxide nucleation layer has proven challenging. By using plasma-enhanced atomic layer deposition (PEALD) and TiO2 as a nucleation layer, we achieved electrically continuous PEALD platinum films down to a thickness of 3.7 nm. Results show that for films as thin as 5.7 nm, the Mayadas-Shatzkes (MS) model for electrical conductivity and the Tellier-Tosser model for temperature coefficient of resistance hold. Although the experimental values start to deviate from the MS model below 5.7 nm because of incomplete Pt coverage, the films still show root mean square electrical stability better than 50 ppm over time, indicating that these films are not only electrically continuous but also sufficiently reliable for use in many practical applications.
View details for DOI 10.1021/acsami.8b21054
View details for Web of Science ID 000460996900096
View details for PubMedID 30707831
View details for PubMedCentralID PMC6407042
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Direct Detection of Akhiezer Damping in a Silicon MEMS Resonator.
Scientific reports
2019; 9 (1): 2244
Abstract
Silicon Microelectromechanical Systems (MEMS) resonators have broad commercial applications for timing and inertial sensing. However, the performance of MEMS resonators is constrained by dissipation mechanisms, some of which are easily detected and well-understood, but some of which have never been directly observed. In this work, we present measurements of the quality factor, Q, for a family of single crystal silicon Lame-mode resonators as a function of temperature, from 80-300K. By comparing these Q measurements on resonators with variations in design, dimensions, and anchors, we have been able to show that gas damping, thermoelastic dissipation, and anchor damping are not significant dissipation mechanisms for these resonators. The measured f·Q product for these devices approaches 2*1013, which is consistent with the expected range for Akhiezer damping, and the dependence of Q on temperature and geometry is consistent with expectations for Akhiezer damping. These results thus provide the first clear, direct detection of Akhiezer dissipation in a MEMS resonator, which is widely considered to be the ultimate limit to Q in silicon MEMS devices.
View details for PubMedID 30783192
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Direct Detection of Akhiezer Damping in a Silicon MEMS Resonator
SCIENTIFIC REPORTS
2019; 9
View details for DOI 10.1038/s41598-019-38847-6
View details for Web of Science ID 000459092800014
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High-speed video microscopy and numerical modeling of bubble dynamics near a surface of urinary stone.
The Journal of the Acoustical Society of America
2019; 146 (1): 516
Abstract
Ultra-high-speed video microscopy and numerical modeling were used to assess the dynamics of microbubbles at the surface of urinary stones. Lipid-shell microbubbles designed to accumulate on stone surfaces were driven by bursts of ultrasound in the sub-MHz range with pressure amplitudes on the order of 1 MPa. Microbubbles were observed to undergo repeated cycles of expansion and violent collapse. At maximum expansion, the microbubbles' cross-section resembled an ellipse truncated by the stone. Approximating the bubble shape as an oblate spheroid, this study modeled the collapse by solving the multicomponent Euler equations with a two-dimensional-axisymmetric code with adaptive mesh refinement for fine resolution of the gas-liquid interface. Modeled bubble collapse and high-speed video microscopy showed a distinctive circumferential pinching during the collapse. In the numerical model, this pinching was associated with bidirectional microjetting normal to the rigid surface and toroidal collapse of the bubble. Modeled pressure spikes had amplitudes two-to-three orders of magnitude greater than that of the driving wave. Micro-computed tomography was used to study surface erosion and formation of microcracks from the action of microbubbles. This study suggests that engineered microbubbles enable stone-treatment modalities with driving pressures significantly lower than those required without the microbubbles.
View details for DOI 10.1121/1.5116693
View details for PubMedID 31370610
View details for PubMedCentralID PMC6660306
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Pseudo-Extensional Mode MEMS Ring Gyroscope
IEEE. 2019
View details for Web of Science ID 000490937200018
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Dynamic modulation of modal coupling in microelectromechanical gyroscopic ring resonators.
Nature communications
2019; 10 (1): 4980
Abstract
Understanding and controlling modal coupling in micro/nanomechanical devices is integral to the design of high-accuracy timing references and inertial sensors. However, insight into specific physical mechanisms underlying modal coupling, and the ability to tune such interactions is limited. Here, we demonstrate that tuneable mode coupling can be achieved in capacitive microelectromechanical devices with dynamic electrostatic fields enabling strong coupling between otherwise uncoupled modes. A vacuum-sealed microelectromechanical silicon ring resonator is employed in this work, with relevance to the gyroscopic lateral modes of vibration. It is shown that a parametric pumping scheme can be implemented through capacitive electrodes surrounding the device that allows for the mode coupling strength to be dynamically tuned, as well as allowing greater flexibility in the control of the coupling stiffness. Electrostatic pump based sideband coupling is demonstrated, and compared to conventional strain-mediated sideband operations. Electrostatic coupling is shown to be very efficient, enabling strong, tunable dynamical coupling.
View details for DOI 10.1038/s41467-019-12796-0
View details for PubMedID 31672971
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NONLINEARITY OF DEGENERATELY DOPED FLEXURAL MODE SILICON MICROMECHANICAL RESONATORS
IEEE. 2019: 1897–1900
View details for Web of Science ID 000539487000480
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SIGNAL ENHANCEMENT IN MEM RESONANT SENSORS USING PARAMETRIC SUPPRESSION
IEEE. 2019: 881–84
View details for Web of Science ID 000539487000222
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EFFECT OF SUBSTRATE THICKNESS ON ANCHOR DAMPING IN MEMS DEVICES
IEEE. 2019: 1843–45
View details for Web of Science ID 000539487000466
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EXPERIMENTALLY OBSERVED NONLINEAR DISSIPATION LINKED TO CONTRIBUTIONS FROM GAS DAMPING AND TED IN MEMS FLEXURAL MODE RESONATORS
IEEE. 2019: 2095–98
View details for Web of Science ID 000539487000530
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AN OVEN-CONTROLLED MEMS OSCILLATOR (OCMO) WITH SUB 10MW, +/- 1.5 PPB STABILITY OVER TEMPERATURE
IEEE. 2019: 2072–75
View details for Web of Science ID 000539487000524
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A Dual-Axis Resonant Accelerometer Based on Electrostatic Stiffness Modulation in Epi-Seal Process
IEEE. 2019
View details for Web of Science ID 000534184600112
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Effective quality factor tuning mechanisms in micromechanical resonators
APPLIED PHYSICS REVIEWS
2018; 5 (4)
View details for DOI 10.1063/1.5027850
View details for Web of Science ID 000454617500019
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Thermal-Piezoresistive Tuning of the Effective Quality Factor of a Micromechanical Resonator
PHYSICAL REVIEW APPLIED
2018; 10 (4)
View details for DOI 10.1103/PhysRevApplied.10.044055
View details for Web of Science ID 000448061700003
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Direct Detection of Anchor Damping in MEMS Tuning Fork Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2018; 27 (5): 800–809
View details for DOI 10.1109/JMEMS.2018.2859958
View details for Web of Science ID 000446657400006
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Assessing failure in epitaxially encapsulated micro-scale sensors using micro and nano x-ray computed tomography
MRS COMMUNICATIONS
2018; 8 (2): 275–82
View details for DOI 10.1557/mrc.2018.70
View details for Web of Science ID 000437442100008
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Dielectric barrier layers by low-temperature plasma-enhanced atomic layer deposition of silicon dioxide
THIN SOLID FILMS
2018; 649: 24–29
View details for DOI 10.1016/j.tsf.2018.01.019
View details for Web of Science ID 000427524100005
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HIGH STABILITY THERMAL ACCELEROMETER BASED ON ULTRATHIN PLATINUM ALD NANOSTRUCTURES
IEEE. 2018: 976–79
View details for Web of Science ID 000434960900256
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Experimental observations and numerical modeling of lipid-shell microbubbles with calcium-adhering moieties for minimally-invasive treatment of urinary stones.
Proceedings of meetings on acoustics. Acoustical Society of America
2018; 35 (1)
Abstract
A novel treatment modality incorporating calcium-adhering microbubbles has recently entered human clinical trials as a new minimally-invasive approach to treat urinary stones. In this treatment method, lipid-shell gas-core microbubbles can be introduced into the urinary tract through a catheter. Lipid moities with calcium-adherance properties incorporated into the lipid shell facilitate binding to stones. The microbubbles can be excited by an extracorporeal source of quasi-collimated ultrasound. Alternatively, the microbubbles can be excited by an intraluminal source, such as a fiber-optic laser. With either excitation technique, calcium-adhering microbubbles can significantly increase rates of erosion, pitting, and fragmentation of stones. We report here on new experiments using high-speed photography to characterize microbubble expansion and collapse. The bubble geometry observed in the experiments was used as one of the initial shapes for the numerical modeling. The modeling showed that the bubble dynamics strongly depends on bubble shape and stand-off distance. For the experimentally observed shape of microbubbles, the numerical modeling showed that the collapse of the microbubbles was associated with pressure increases of some two-to-three orders of magnitude compared to the excitation source pressures. This in-vitro study provides key insights into the use of microbubbles with calcium-adhering moieties in treatment of urinary stones.
View details for DOI 10.1121/2.0000958
View details for PubMedID 32440311
View details for PubMedCentralID PMC7241592
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Lateral Diffusion Doping of Silicon for Temperature Compensation of MEMS Resonators
IEEE. 2018: 125–28
View details for Web of Science ID 000490927100033
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Active Temperature Compensation of Thermal Accelerometer for Improved Stability
IEEE. 2018: 155–56
View details for Web of Science ID 000490927100042
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Investigation of Orientation Dependence of the Thermal Expansion Coefficient in Silicon MEMS Resonators
IEEE. 2018: 108–11
View details for Web of Science ID 000461285600032
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High Quality Factor Mode Ordered Dual Foucault Pendulum Gyroscope
IEEE. 2018: 1130–33
View details for Web of Science ID 000468199300293
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EPITAXIAL ENCAPSULATION OF FULLY DIFFERENTIAL ELECTRODES AND LARGE TRANSDUCTION GAPS FOR MEMS RESONANT STRUCTURES
IEEE. 2018: 483–86
View details for Web of Science ID 000434960900129
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EXPERIMENTAL FRACTAL-LIKE INSTABILITY BANDS IN A RESONANT SILICON-SILICON CONTACT PULL-IN VIBRATION DETECTOR
IEEE. 2018: 984–87
View details for Web of Science ID 000434960900258
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TEMPERATURE COMPENSATION OF RESONANT ACCELEROMETER VIA NONLINEAR OPERATION
IEEE. 2018: 1012–15
View details for Web of Science ID 000434960900265
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UNANTICIPATED RESULTS IN THE FIRST DIRECT MEASUREMENTS OF ANCHOR DAMPING IN MEMS RESONATORS
IEEE. 2018: 543–46
View details for Web of Science ID 000434960900145
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THERMAL EFFECTS OF OVENIZED CLOCKS ON EPISEAL ENCAPSULATED INERTIAL MEASUREMENT UNITS
IEEE. 2018: 980–83
View details for Web of Science ID 000434960900257
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Robust Method of Fabricating Epitaxially Encapsulated MEMS Devices with Large Gaps
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2017; 26 (6): 1235–43
View details for DOI 10.1109/JMEMS.2017.2758388
View details for Web of Science ID 000417784500009
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Measurement of Young's modulus and residual stress of atomic layer deposited Al2O3 and Pt thin films
JOURNAL OF MICROMECHANICS AND MICROENGINEERING
2017; 27 (8)
View details for DOI 10.1088/1361-6439/aa73e6
View details for Web of Science ID 000415698500005
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Phonon conduction in silicon nanobeams
APPLIED PHYSICS LETTERS
2017; 110 (21)
View details for DOI 10.1063/1.4983790
View details for Web of Science ID 000402320000033
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Modeling and Analysis for Thermal Management in Gallium Nitride HEMTs Using Microfluidic Cooling
JOURNAL OF ELECTRONIC PACKAGING
2017; 139 (1)
View details for DOI 10.1115/1.4035064
View details for Web of Science ID 000395123200003
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Compact Roll-Pitch-Yaw Gyroscope Implemented in Wafer-level Epitaxial Silicon Encapsulation Process
IEEE. 2017: 181–82
View details for Web of Science ID 000403208300050
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MICRO-TETHERING FOR IN-PROCESS STICTION MITIGATION OF HIGHLY COMPLIANT STRUCTURES
IEEE. 2017: 675–78
View details for Web of Science ID 000402552000175
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HIGH-G (>20,000g) INERTIAL SHOCK SURVIVABILITY OF EPITAXIALLY ENCAPSULATED SILICON MEMS DEVICES
IEEE. 2017: 1122–25
View details for Web of Science ID 000402552000288
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EPITAXIALLY-ENCAPSULATED QUAD MASS RESONATOR WITH SHAPED COMB FINGERS FOR FREQUENCY TUNING
IEEE. 2017: 1111–14
View details for Web of Science ID 000402552000285
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TRI-MODE OPERATION OF HIGHLY DOPED SILICON RESONATORS FOR TEMPERATURE COMPENSATED TIMING REFERENCES
IEEE. 2017: 1158–61
View details for Web of Science ID 000402552000297
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MANIPULATION OF HEAT FLUX PATHS IN THERMO-ELASTICALLY DAMPED RESONATORS FOR Q OPTIMIZATION
IEEE. 2017: 1130–33
View details for Web of Science ID 000402552000290
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ENVIRONMENTALLY ROBUST DIFFERENTIAL RESONANT ACCELEROMETER IN A WAFER-SCALE ENCAPSULATION PROCESS
IEEE. 2017: 17–20
View details for Web of Science ID 000402552000005
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ON CROSS-TALK BETWEEN GYROSCOPES INTEGRATED ON A FOLDED MEMS IMU CUBE
IEEE. 2017: 1142–45
View details for Web of Science ID 000402552000293
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Fabrication of Wide and Deep Cavities for Silicon MEMS Devices Without Wafer Bonding
IEEE. 2017: 113–16
View details for Web of Science ID 000403208300030
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Electrostatic Tuning of Temperature Coefficient of Frequency of Anisotropic Disk-Shaped Resonators
IEEE. 2017: 164–67
View details for Web of Science ID 000403208300044
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Dual-Resonator MEMS Lorentz Force Magnetometer Based on Differential Frequency Modulation
IEEE. 2017: 160–63
View details for Web of Science ID 000403208300043
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EPITAXIALLY ENCAPSULATED RESONANT ACCELEROMETER WITH AN ON-CHIP MICRO-OVEN
IEEE. 2017: 595–98
View details for Web of Science ID 000426701400147
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WAFER-SCALE ENCAPSULATION OF FULLY DIFFERENTIAL ELECTRODES FOR MUTLI-AXIS INERTIAL SENSING
IEEE. 2017: 591–94
View details for Web of Science ID 000426701400146
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TOPOLOGY OPTIMIZATION FOR REDUCTION OF THERMO-ELASTIC DISSIPATION IN MEMS RESONATORS
IEEE. 2017: 794–97
View details for Web of Science ID 000426701400196
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DIRECT COMPARISON OF STICTION PROPERTIES OF OXIDE COATED POLYSILICON AND SMOOTH SINGLE CRYSTAL SILICON
IEEE. 2017: 1203–6
View details for Web of Science ID 000426701400298
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DUAL-RESONATOR MEMS MAGNETIC SENSOR WITH DIFFERENTIAL AMPLITUDE MODULATION
IEEE. 2017: 814–17
View details for Web of Science ID 000426701400201
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Direct Measurements of Anchor Damping in MEMS Resonators
IEEE. 2017: 10–12
View details for Web of Science ID 000427677500004
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EFFECTIVE QUALITY FACTOR AND TEMPERATURE DEPENDENCE OF SELF-OSCILLATIONS IN A THERMAL-PIEZORESISTIVELY PUMPED RESONATOR
IEEE. 2017: 1907–10
View details for Web of Science ID 000426701400471
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Nonlinear damping and dephasing in nanomechanical systems
PHYSICAL REVIEW B
2016; 94 (19)
View details for DOI 10.1103/PhysRevB.94.195440
View details for Web of Science ID 000388818000017
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Nonlinearity of Degenerately Doped Bulk-Mode Silicon MEMS Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2016; 25 (5): 859-869
View details for DOI 10.1109/JMEMS.2016.2586099
View details for Web of Science ID 000389897800006
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Phase Noise Reduction in an MEMS Oscillator Using a Nonlinearly Enhanced Synchronization Domain
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2016; 25 (5): 870-876
View details for DOI 10.1109/JMEMS.2016.2590881
View details for Web of Science ID 000389897800007
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Parallel preparation of plan-view transmission electron microscopy specimens by vapor-phase etching with integrated etch stops
ULTRAMICROSCOPY
2016; 166: 39-47
Abstract
Specimen preparation remains a practical challenge in transmission electron microscopy and frequently limits the quality of structural and chemical characterization data obtained. Prevailing methods for thinning of specimens to electron transparency are serial in nature, time consuming, and prone to producing artifacts and specimen failure. This work presents an alternative method for the preparation of plan-view specimens using isotropic vapor-phase etching with integrated etch stops. An ultrathin amorphous etch-stop layer simultaneously serves as an electron transparent support membrane whose thickness is defined by a controlled growth process such as atomic layer deposition with sub-nanometer precision. This approach eliminates the need for mechanical polishing or ion milling to achieve electron transparency, and reduces the occurrence of preparation induced artifacts. Furthermore, multiple specimens from a plurality of samples can be thinned in parallel due to high selectivity of the vapor-phase etching process. These features enable dramatic reductions in preparation time and cost without sacrificing specimen quality and provide advantages over wet etching techniques. Finally, we demonstrate a platform for high-throughput transmission electron microscopy of plan-view specimens by combining the parallel preparation capabilities of vapor-phase etching with wafer-scale micro- and nanofabrication.
View details for DOI 10.1016/j.ultramic.2016.04.003
View details for Web of Science ID 000376734400005
View details for PubMedID 27160487
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Experimental Investigation Into Stiction Forces and Dynamic Mechanical Anti-Stiction Solutions in Ultra-Clean Encapsulated MEMS Devices
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2016; 25 (3): 469-478
View details for DOI 10.1109/JMEMS.2016.2525008
View details for Web of Science ID 000377372900007
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A Unified Epi-Seal Process for Fabrication of High-Stability Microelectromechanical Devices
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2016; 25 (3): 489-497
View details for DOI 10.1109/JMEMS.2016.2537829
View details for Web of Science ID 000377372900009
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Characterization of MEMS Resonator Nonlinearities Using the Ringdown Response
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2016; 25 (2): 297-303
View details for DOI 10.1109/JMEMS.2016.2529296
View details for Web of Science ID 000374177500008
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Stable Encapsulated Charge-Biased Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2016; 25 (1): 30-37
View details for DOI 10.1109/JMEMS.2015.2483365
View details for Web of Science ID 000370763900003
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Autonomous Calibration of MEMS Disk Resonating Gyroscope for Improved Sensor Performance
IEEE. 2016: 5803–10
View details for Web of Science ID 000388376105138
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OVERCOMING STICTION FORCES WITH RESONANT OVER-TRAVEL STOPS
IEEE. 2016: 47–50
View details for Web of Science ID 000381797300014
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STOCHASTIC METHOD FOR DISK RESONATING GYROSCOPE MODE MATCHING AND QUADRATURE NULLING
IEEE. 2016: 998–1001
View details for Web of Science ID 000381797300261
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Q-FACTOR OPTIMIZATION IN DISK RESONATOR GYROSCOPES VIA GEOMETRIC PARAMETERIZATION
IEEE. 2016: 994–97
View details for Web of Science ID 000381797300260
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ENCAPSULATED DISK RESONATOR GYROSCOPE WITH DIFFERENTIAL INTERNAL ELECTRODES
IEEE. 2016: 962–65
View details for Web of Science ID 000381797300252
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EPITAXIALLY-ENCAPSULATED QUAD MASS GYROSCOPE WITH NONLINEARITY COMPENSATION
IEEE. 2016: 966–69
View details for Web of Science ID 000381797300253
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Mode-Matched MEMS Coriolis Vibratory Gyroscopes: Myth or Reality?
IEEE. 2016: 1–4
View details for Web of Science ID 000389021800001
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OVENIZED DUAL-MODE CLOCK (ODNIC) BASED ON HIGHLY DOPED SINGLE CRYSTAL SILICON RESONATORS
IEEE. 2016: 91–94
View details for Web of Science ID 000381797300025
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Investigation of a Vacuum Encapsulated Si-to-Si Contact Microswitch Operated From-60 degrees C to 400 degrees C
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2015; 24 (6): 1906-1915
View details for DOI 10.1109/JMEMS.2015.2451191
View details for Web of Science ID 000365987000028
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Temperature Dependence of the Elastic Constants of Doped Silicon (vol 24, pg 730, 2015)
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2015; 24 (6): 2178
View details for DOI 10.1109/JMEMS.2015.2483373
View details for Web of Science ID 000365987000058
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Characterization of Oxide-Coated Polysilicon Disk Resonator Gyroscope Within a Wafer-Scale Encapsulation Process
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2015; 24 (6): 1687-1694
View details for DOI 10.1109/JMEMS.2015.2478034
View details for Web of Science ID 000365987000005
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Nonhomogeneous morphology and the elastic modulus of aligned carbon nanotube films
JOURNAL OF MICROMECHANICS AND MICROENGINEERING
2015; 25 (11)
View details for DOI 10.1088/0960-1317/25/11/115023
View details for Web of Science ID 000366862100026
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Thermal Conduction in Vertically Aligned Copper Nanowire Arrays and Composites.
ACS applied materials & interfaces
2015; 7 (34): 19251-19259
Abstract
The ability to efficiently and reliably transfer heat between sources and sinks is often a bottleneck in the thermal management of modern energy conversion technologies ranging from microelectronics to thermoelectric power generation. These interfaces contribute parasitic thermal resistances that reduce device performance and are subjected to thermomechanical stresses that degrade device lifetime. Dense arrays of vertically aligned metal nanowires (NWs) offer the unique combination of thermal conductance from the constituent metal and mechanical compliance from the high aspect ratio geometry to increase interfacial heat transfer and device reliability. In the present work, we synthesize copper NW arrays directly onto substrates via templated electrodeposition and extend this technique through the use of a sacrificial overplating layer to achieve improved uniformity. Furthermore, we infiltrate the array with an organic phase change material and demonstrate the preservation of thermal properties. We use the 3ω method to measure the axial thermal conductivity of freestanding copper NW arrays to be as high as 70 W m(-1) K(-1), which is more than an order of magnitude larger than most commercial interface materials and enhanced-conductivity nanocomposites reported in the literature. These arrays are highly anisotropic, and the lateral thermal conductivity is found to be only 1-2 W m(-1) K(-1). We use these measured properties to elucidate the governing array-scale transport mechanisms, which include the effects of morphology and energy carrier scattering from size effects and grain boundaries.
View details for DOI 10.1021/acsami.5b05147
View details for PubMedID 26284489
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Multifunctional Integrated Sensors for Multiparameter Monitoring Applications
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2015; 24 (4): 810-821
View details for DOI 10.1109/JMEMS.2014.2349894
View details for Web of Science ID 000358952600007
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Targeted microbubbles: a novel application for the treatment of kidney stones
BJU INTERNATIONAL
2015; 116 (1): 9-16
Abstract
Kidney stone disease is endemic. Extracorporeal shockwave lithotripsy was the first major technological breakthrough where focused shockwaves were used to fragment stones in the kidney or ureter. The shockwaves induced the formation of cavitation bubbles, whose collapse released energy at the stone, and the energy fragmented the kidney stones into pieces small enough to be passed spontaneously. Can the concept of microbubbles be used without the bulky machine? The logical progression was to manufacture these powerful microbubbles ex vivo and inject these bubbles directly into the collecting system. An external source can be used to induce cavitation once the microbubbles are at their target; the key is targeting these microbubbles to specifically bind to kidney stones. Two important observations have been established: (i) bisphosphonates attach to hydroxyapatite crystals with high affinity; and (ii) there is substantial hydroxyapatite in most kidney stones. The microbubbles can be equipped with bisphosphonate tags to specifically target kidney stones. These bubbles will preferentially bind to the stone and not surrounding tissue, reducing collateral damage. Ultrasound or another suitable form of energy is then applied causing the microbubbles to induce cavitation and fragment the stones. This can be used as an adjunct to ureteroscopy or percutaneous lithotripsy to aid in fragmentation. Randall's plaques, which also contain hydroxyapatite crystals, can also be targeted to pre-emptively destroy these stone precursors. Additionally, targeted microbubbles can aid in kidney stone diagnostics by virtue of being used as an adjunct to traditional imaging methods, especially useful in high-risk patient populations. This novel application of targeted microbubble technology not only represents the next frontier in minimally invasive stone surgery, but a platform technology for other areas of medicine.
View details for DOI 10.1111/bju.12996
View details for Web of Science ID 000357048700006
View details for PubMedID 25402588
View details for PubMedCentralID PMC4433869
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Predicting the closed-loop stability and oscillation amplitude of nonlinear parametrically amplified oscillators
APPLIED PHYSICS LETTERS
2015; 106 (23)
View details for DOI 10.1063/1.4922533
View details for Web of Science ID 000356170900043
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Temperature Dependence of the Elastic Constants of Doped Silicon
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2015; 24 (3): 730-741
View details for DOI 10.1109/JMEMS.2014.2347205
View details for Web of Science ID 000356520200028
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Mode-Matching of Wineglass Mode Disk Resonator Gyroscope in (100) Single Crystal Silicon
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2015; 24 (2): 343-350
View details for DOI 10.1109/JMEMS.2014.2330590
View details for Web of Science ID 000352278200012
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Fatigue Experiments on Single Crystal Silicon in an Oxygen-Free Environment
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2015; 24 (2): 351-359
View details for DOI 10.1109/JMEMS.2014.2331231
View details for Web of Science ID 000352278200013
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Accurate Modeling of Quality Factor Behavior of Complex Silicon MEMS Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2015; 24 (2): 276-288
View details for DOI 10.1109/JMEMS.2014.2374451
View details for Web of Science ID 000352278200006
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Self-induced parametric amplification arising from nonlinear elastic coupling in a micromechanical resonating disk gyroscope
SCIENTIFIC REPORTS
2015; 5
Abstract
Parametric amplification, resulting from intentionally varying a parameter in a resonator at twice its resonant frequency, has been successfully employed to increase the sensitivity of many micro- and nano-scale sensors. Here, we introduce the concept of self-induced parametric amplification, which arises naturally from nonlinear elastic coupling between the degenerate vibration modes in a micromechanical disk-resonator, and is not externally applied. The device functions as a gyroscope wherein angular rotation is detected from Coriolis coupling of elastic vibration energy from a driven vibration mode into a second degenerate sensing mode. While nonlinear elasticity in silicon resonators is extremely weak, in this high quality-factor device, ppm-level nonlinear elastic effects result in an order-of-magnitude increase in the observed sensitivity to Coriolis force relative to linear theory. Perfect degeneracy of the primary and secondary vibration modes is achieved through electrostatic frequency tuning, which also enables the phase and frequency of the parametric coupling to be varied, and we show that the resulting phase and frequency dependence of the amplification follow the theory of parametric resonance. We expect that this phenomenon will be useful for both fundamental studies of dynamic systems with low dissipation and for increasing signal-to-noise ratio in practical applications such as gyroscopes.
View details for DOI 10.1038/srep09036
View details for Web of Science ID 000351144900013
View details for PubMedID 25762243
View details for PubMedCentralID PMC4356982
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Disk Resonator Gyroscope with Whole-Angle Mode Operation
IEEE. 2015: 9–12
View details for Web of Science ID 000380378400003
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A 7PPM, 6 degrees/HR FREQUENCY-OUTPUT MEMS GYROSCOPE
IEEE. 2015: 33–36
View details for Web of Science ID 000370382900011
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MODELING THE EFFECT OF ANCHOR GEOMETRY ON THE QUALITY FACTOR OF BULK MODE RESONATORS
IEEE. 2015: 1997–2000
View details for Web of Science ID 000380461400499
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A UNIFIED EPI-SEAL PROCESS FOR RESONATORS AND INERTIAL SENSORS
IEEE. 2015: 1326–29
View details for Web of Science ID 000380461400330
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IN-SITU OVENIZATION OF LAME-MODE SILICON RESONATORS FOR TEMPERATURE COMPENSATION
IEEE. 2015: 809–12
View details for Web of Science ID 000370382900213
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EXPERIMENTAL INVESTIGATION ON MODE COUPLING OF BULK MODE SILICON MEMS RESONATORS
IEEE. 2015: 1008–11
View details for Web of Science ID 000370382900263
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TUNABLE QUALITY FACTOR THROUGH 1:1 MODAL COUPLING IN A DISK RESONATOR
IEEE. 2015: 1199–1202
View details for Web of Science ID 000380440800316
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SILICON-TO-SILICON MICROSWITCH WITH WIDE OPERATION TEMPERATURE RANGE
IEEE. 2015: 2105–8
View details for Web of Science ID 000380461400526
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Encapsulated high frequency (235 kHz), high-Q (100 k) disk resonator gyroscope with electrostatic parametric pump
APPLIED PHYSICS LETTERS
2014; 105 (24)
View details for DOI 10.1063/1.4904468
View details for Web of Science ID 000346643600074
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Fabrication and Characterization of a Vacuum Encapsulated Curved Beam Switch for Harsh Environment Application
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2014; 23 (5): 1121-1130
View details for DOI 10.1109/JMEMS.2014.2305754
View details for Web of Science ID 000343318500014
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CHARACTERIZATION OF STICTION FORCES IN ULTRA-CLEAN ENCAPSULATED MEMS DEVICES
IEEE. 2014: 588–91
View details for Web of Science ID 000352217500152
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STABLE PULL-IN ELECTRODES FOR NARROW GAP ACTUATION
IEEE. 2014: 1281–84
View details for Web of Science ID 000352217500326
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STABLE CHARGE-BIASED CAPACITIVE RESONATORS WITH ENCAPSULATED SWITCHES
IEEE. 2014: 1277–80
View details for Web of Science ID 000352217500325
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Zipping, entanglement, and the elastic modulus of aligned single-walled carbon nanotube films
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2013; 110 (51): 20426-20430
Abstract
Reliably routing heat to and from conversion materials is a daunting challenge for a variety of innovative energy technologies--from thermal solar to automotive waste heat recovery systems--whose efficiencies degrade due to massive thermomechanical stresses at interfaces. This problem may soon be addressed by adhesives based on vertically aligned carbon nanotubes, which promise the revolutionary combination of high through-plane thermal conductivity and vanishing in-plane mechanical stiffness. Here, we report the data for the in-plane modulus of aligned single-walled carbon nanotube films using a microfabricated resonator method. Molecular simulations and electron microscopy identify the nanoscale mechanisms responsible for this property. The zipping and unzipping of adjacent nanotubes and the degree of alignment and entanglement are shown to govern the spatially varying local modulus, thereby providing the route to engineered materials with outstanding combinations of mechanical and thermal properties.
View details for DOI 10.1073/pnas.1312253110
View details for Web of Science ID 000328548600031
View details for PubMedID 24309375
View details for PubMedCentralID PMC3870663
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Experimental Validation of Topology Optimization for RF MEMS Capacitive Switch Design
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2013; 22 (6): 1296-1309
View details for DOI 10.1109/JMEMS.2013.2283241
View details for Web of Science ID 000328047300008
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The effect of the temperature-dependent nonlinearities on the temperature stability of micromechanical resonators
JOURNAL OF APPLIED PHYSICS
2013; 114 (15)
View details for DOI 10.1063/1.4825327
View details for Web of Science ID 000326117900025
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Lorentz force magnetometer using a micromechanical oscillator
APPLIED PHYSICS LETTERS
2013; 103 (17)
View details for DOI 10.1063/1.4826278
View details for Web of Science ID 000326455100079
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Vacuum encapsulated resonators for humidity measurement
SENSORS AND ACTUATORS B-CHEMICAL
2013; 185: 575-581
View details for DOI 10.1016/j.snb.2013.05.016
View details for Web of Science ID 000321509600077
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Crystallographic effects in modeling fundamental behavior of MEMS silicon resonators
MICROELECTRONICS JOURNAL
2013; 44 (7): 586-591
View details for DOI 10.1016/j.mejo.2013.03.010
View details for Web of Science ID 000321411900004
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Stability of Silicon Microelectromechanical Systems Resonant Thermometers
IEEE SENSORS JOURNAL
2013; 13 (3)
View details for DOI 10.1109/JSEN.2012.2227708
View details for Web of Science ID 000314690100011
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Topology Optimization of Stressed Capacitive RF MEMS Switches
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2013; 22 (1): 206-215
View details for DOI 10.1109/JMEMS.2012.2224640
View details for Web of Science ID 000314726900028
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RESONANT PRESSURE SENSOR WITH ON-CHIP TEMPERATURE AND STRAIN SENSORS FOR ERROR CORRECTION
26th IEEE International Conference on Micro Electro Mechanical Systems (MEMS)
IEEE. 2013: 45–48
View details for Web of Science ID 000320549200012
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Quantum limit of quality factor in silicon micro and nano mechanical resonators.
Scientific reports
2013; 3: 3244-?
Abstract
Micromechanical resonators are promising replacements for quartz crystals for timing and frequency references owing to potential for compactness, integrability with CMOS fabrication processes, low cost, and low power consumption. To be used in high performance reference application, resonators should obtain a high quality factor. The limit of the quality factor achieved by a resonator is set by the material properties, geometry and operating condition. Some recent resonators properly designed for exploiting bulk-acoustic resonance have been demonstrated to operate close to the quantum mechanical limit for the quality factor and frequency product (Q-f). Here, we describe the physics that gives rise to the quantum limit to the Q-f product, explain design strategies for minimizing other dissipation sources, and present new results from several different resonators that approach the limit.
View details for DOI 10.1038/srep03244
View details for PubMedID 24247809
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SUB-10 NANOMETER UNCOOLED PLATINUM BOLOMETERS VIA PLASMA ENHANCED ATOMIC LAYER DEPOSITION
IEEE. 2013: 185–88
View details for Web of Science ID 000320549200048
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Quantum limit of quality factor in silicon micro and nano mechanical resonators.
Scientific reports
2013; 3: 3244-?
Abstract
Micromechanical resonators are promising replacements for quartz crystals for timing and frequency references owing to potential for compactness, integrability with CMOS fabrication processes, low cost, and low power consumption. To be used in high performance reference application, resonators should obtain a high quality factor. The limit of the quality factor achieved by a resonator is set by the material properties, geometry and operating condition. Some recent resonators properly designed for exploiting bulk-acoustic resonance have been demonstrated to operate close to the quantum mechanical limit for the quality factor and frequency product (Q-f). Here, we describe the physics that gives rise to the quantum limit to the Q-f product, explain design strategies for minimizing other dissipation sources, and present new results from several different resonators that approach the limit.
View details for DOI 10.1038/srep03244
View details for PubMedID 24247809
View details for PubMedCentralID PMC3832850
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Bidirectionally tuning Kapitza conductance through the inclusion of substitutional impurities
JOURNAL OF APPLIED PHYSICS
2012; 112 (7)
View details for DOI 10.1063/1.4757941
View details for Web of Science ID 000310489400041
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Phase and thickness dependent modulus of Ge2Sb2Te5 films down to 25 nm thickness
APPLIED PHYSICS LETTERS
2012; 100 (16)
View details for DOI 10.1063/1.3699227
View details for Web of Science ID 000303128500018
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Electrical and Thermal Conduction in Atomic Layer Deposition Nanobridges Down to 7 nm Thickness
NANO LETTERS
2012; 12 (2): 683-686
Abstract
While the literature is rich with data for the electrical behavior of nanotransistors based on semiconductor nanowires and carbon nanotubes, few data are available for ultrascaled metal interconnects that will be demanded by these devices. Atomic layer deposition (ALD), which uses a sequence of self-limiting surface reactions to achieve high-quality nanolayers, provides an unique opportunity to study the limits of electrical and thermal conduction in metal interconnects. This work measures and interprets the electrical and thermal conductivities of free-standing platinum films of thickness 7.3, 9.8, and 12.1 nm in the temperature range from 50 to 320 K. Conductivity data for the 7.3 nm bridge are reduced by 77.8% (electrical) and 66.3% (thermal) compared to bulk values due to electron scattering at material and grain boundaries. The measurement results indicate that the contribution of phonon conduction is significant in the total thermal conductivity of the ALD films.
View details for DOI 10.1021/nl203548w
View details for PubMedID 22224582
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Mechanical characterization of aligned multi-walled carbon nanotube films using microfabricated resonators
CARBON
2012; 50 (2): 347-355
View details for DOI 10.1016/j.carbon.2011.08.009
View details for Web of Science ID 000297397700001
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Reduction of Initial Stress Stiffening by Topology Optimization
Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)
IEEE COMPUTER SOC. 2012: 148–153
View details for Web of Science ID 000310360600030
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ANHARMONIC PHONON DISPERSION RELATIONS, GROUP VELOCITIES, AND BRANCH-DEPENDENT SPECIFIC HEAT CAPACITIES MEASURED DIRECTLY FROM MOLECULAR DYNAMICS SIMULATIONS AT FINITE TEMPERATURES
ASME Summer Heat Transfer Conference (SHTC)
AMER SOC MECHANICAL ENGINEERS. 2012: 617–624
View details for Web of Science ID 000324956600073
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A SINGLE PROCESS FOR BUILDING CAPACITIVE PRESSURE SENSORS AND TIMING REFERENCES WITH PRECISE CONTROL OF RELEASED AREA USING LATERAL ETCH STOP
25th IEEE International Conference on Micro Electro Mechanical Systems (MEMS)
IEEE. 2012
View details for Web of Science ID 000312912800131
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Crust Removal and Effective Modulus of Aligned Multi-walled Carbon Nanotube Films
13th IEEE InterSociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm)
IEEE. 2012: 1070–1076
View details for Web of Science ID 000312835500139
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Electrostatic Tuning to Achieve Higher Stability Microelectromechanical Composite Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2011; 20 (6): 1355-1365
View details for DOI 10.1109/JMEMS.2011.2168083
View details for Web of Science ID 000297589200016
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Stable Operation of MEMS Oscillators Far Above the Critical Vibration Amplitude in the Nonlinear Regime
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2011; 20 (6): 1228-1230
View details for DOI 10.1109/JMEMS.2011.2170821
View details for Web of Science ID 000297589200002
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Influence of the temperature dependent nonlinearities on the performance of micromechanical resonators
APPLIED PHYSICS LETTERS
2011; 99 (19)
View details for DOI 10.1063/1.3660235
View details for Web of Science ID 000297030200082
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Orientation angle and the adhesion of single gecko setae
JOURNAL OF THE ROYAL SOCIETY INTERFACE
2011; 8 (60): 926-933
Abstract
We investigated the effects of orientation angle on the adhesion of single gecko setae using dual-axis microelectromechanical systems force sensors to simultaneously detect normal and shear force components. Adhesion was highly sensitive to the pitch angle between the substrate and the seta's stalk. Maximum lateral adhesive force was observed with the stalk parallel to the substrate, and adhesion decreased smoothly with increasing pitch. The roll orientation angle only needed to be roughly correct with the spatular tuft of the seta oriented grossly towards the substrate for high adhesion. Also, detailed measurements were made to control for the effect of normal preload forces. Higher normal preload forces caused modest enhancement of the observed lateral adhesive force, provided that adequate contact was made between the seta and the substrate. These results should be useful in the design and manufacture of gecko-inspired synthetic adhesives with anisotropic properties, an area of substantial recent research efforts.
View details for DOI 10.1098/rsif.2010.0720
View details for Web of Science ID 000290898500002
View details for PubMedID 21288955
View details for PubMedCentralID PMC3104340
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AC Polarization for Charge-Drift Elimination in Resonant Electrostatic MEMS and Oscillators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2011; 20 (2): 355-364
View details for DOI 10.1109/JMEMS.2010.2100027
View details for Web of Science ID 000289205400002
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Wafer-Level Epitaxial Silicon Packaging for Out-of-Plane RF MEMS Resonators with Integrated Actuation Electrodes
IEEE TRANSACTIONS ON COMPONENTS PACKAGING AND MANUFACTURING TECHNOLOGY
2011; 1 (3): 310-317
View details for DOI 10.1109/TCPMT.2010.2100711
View details for Web of Science ID 000292780700004
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3-D visualization of flow in microscale jet impingement systems
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
2011; 50 (3): 325-331
View details for DOI 10.1016/j.ijthermalsci.2010.08.005
View details for Web of Science ID 000287285700012
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Motional Impedance of Resonators in the Nonlinear Regime
5th Joint Conference of the 65th IEEE International Frequency Control Symposium/25th European Frequency and Time Forum
IEEE. 2011: 372–377
View details for Web of Science ID 000295261600087
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Tip-Based Nanofabrication: An Approach to True Nanotechnology
SPIE-INT SOC OPTICAL ENGINEERING. 2011
View details for DOI 10.1117/12.887266
View details for Web of Science ID 000291441400002
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Stability Measurements of Silicon MEMS Resonant Thermometers
10th IEEE Conference on Sensors
IEEE. 2011: 1257–1260
View details for Web of Science ID 000299901200304
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Active Electrostatic Compensation of Micromechanical Resonators Under Random Vibrations
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2010; 19 (5): 1270-1272
View details for DOI 10.1109/JMEMS.2010.2067444
View details for Web of Science ID 000283369500028
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Effect of fibril shape on adhesive properties
APPLIED PHYSICS LETTERS
2010; 97 (5)
View details for DOI 10.1063/1.3464553
View details for Web of Science ID 000281059500064
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What is the Young's Modulus of Silicon?
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2010; 19 (2): 229-238
View details for DOI 10.1109/JMEMS.2009.2039697
View details for Web of Science ID 000276257700001
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Characterization of Encapsulated Micromechanical Resonators Sealed and Coated With Polycrystalline SiC
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2010; 19 (2): 357-366
View details for DOI 10.1109/JMEMS.2010.2040460
View details for Web of Science ID 000276257700014
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A Method for Wafer-Scale Encapsulation of Large Lateral Deflection MEMS Devices
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2010; 19 (1): 28-37
View details for DOI 10.1109/JMEMS.2009.2035717
View details for Web of Science ID 000274213700003
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Model and Observations of Dielectric Charge in Thermally Oxidized Silicon Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2010; 19 (1): 162-174
View details for DOI 10.1109/JMEMS.2009.2036274
View details for Web of Science ID 000274213700016
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Real-Time Temperature Compensation of MEMS Oscillators Using an Integrated Micro-Oven and a Phase-Locked Loop
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2010; 19 (1): 192-201
View details for DOI 10.1109/JMEMS.2009.2035932
View details for Web of Science ID 000274213700019
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INFLUENCE OF THE TEMPERATURE DEPENDENT A-F EFFECT ON THE DESIGN AND PERFORMANCE OF MEMS OSCILLATORS
23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2010)
IEEE. 2010: 699–702
View details for Web of Science ID 000278416400173
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STRESS RELAXATION STUDY OF SPUTTERED PLATINUM THIN FILMS AT NEAR ROOM TEMPERATURE USING AN ULTRA-SENSITIVE STRAIN GAUGE
23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2010)
IEEE. 2010: 548–551
View details for Web of Science ID 000278416400135
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NONLINEARITY OF HERMETICALLY ENCAPSULATED HIGH-Q DOUBLE BALANCED BREATHE-MODE RING RESONATOR
23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2010)
IEEE. 2010: 715–718
View details for Web of Science ID 000278416400177
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Encapsulated MEMS Resonators - A technology path for MEMS into Frequency Control Applications
2010 IEEE International Frequency Control Symposium
IEEE. 2010: 1–4
View details for Web of Science ID 000287378700001
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A NOVEL CHARACTERIZATION METHOD FOR TEMPERATURE COMPENSATION OF COMPOSITE RESONATORS
23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2010)
IEEE. 2010: 743–746
View details for Web of Science ID 000278416400184
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CHARGE-DRIFT ELIMINATION IN RESONANT ELECTROSTATIC MEMS
23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2010)
IEEE. 2010: 108–111
View details for Web of Science ID 000278416400025
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HIGH-CYCLIC FATIGUE EXPERIMENTS OF SINGLE CRYSTAL SILICON IN AN OXYGEN-FREE ENVIRONMENT
23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2010)
IEEE. 2010: 224–227
View details for Web of Science ID 000278416400054
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AN OPTIMIZATION DESIGN FOR A MEMS FABRICATED JET IMPINGEMENT COOLING DEVICE
ASME InterPack Conference
AMER SOC MECHANICAL ENGINEERS. 2010: 491–496
View details for Web of Science ID 000282288700064
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Development of wafer scale encapsulation process for large displacement piezoresistive MEMS devices
SENSORS AND ACTUATORS A-PHYSICAL
2009; 156 (2): 275-283
View details for DOI 10.1016/j.sna.2009.09.001
View details for Web of Science ID 000272563900001
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Temperature-Insensitive Composite Micromechanical Resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2009; 18 (6): 1409-1419
View details for DOI 10.1109/JMEMS.2009.2030074
View details for Web of Science ID 000272318900027
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Performance Evaluation and Equivalent Model of Silicon Interconnects for Fully-Encapsulated RF MEMS Devices
IEEE TRANSACTIONS ON ADVANCED PACKAGING
2009; 32 (2): 402-409
View details for DOI 10.1109/TADVP.2008.2005114
View details for Web of Science ID 000266778000018
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Multimode thermoelastic dissipation
JOURNAL OF APPLIED PHYSICS
2009; 105 (4)
View details for DOI 10.1063/1.3072682
View details for Web of Science ID 000263803300018
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Hermeticity and diffusion investigation in polysilicon film encapsulation for microelectromechanical systems
JOURNAL OF APPLIED PHYSICS
2009; 105 (1)
View details for DOI 10.1063/1.3054366
View details for Web of Science ID 000262534100047
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AN INTEGRATED SOLUTION FOR WAFER-LEVEL PACKAGING AND ELECTROSTATIC ACTUATION OF OUT-OF-PLANE DEVICES
22nd International Conference on Micro Electro Mechanical Systems (MEMS)
IEEE. 2009: 1071–1074
View details for Web of Science ID 000341431500268
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EPITAXIAL SILICON MICROSHELL VACUUM-ENCAPSULATED CMOS-COMPATIBLE 200 MHz BULK-MODE RESONATOR
22nd International Conference on Micro Electro Mechanical Systems (MEMS)
IEEE. 2009: 23–26
View details for Web of Science ID 000341431500006
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ACCELERATION COMPENSATION OF MEMS RESONATORS USING ELECTROSTATIC TUNING
22nd International Conference on Micro Electro Mechanical Systems (MEMS)
IEEE. 2009: 805–808
View details for Web of Science ID 000341431500201
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3-D VISUALIZATION OF FLOW IN MICROSCALE JET IMPINGEMENT SYSTEM
7th International Conference on Nanochannels, Microchannels and Minichannels
AMER SOC MECHANICAL ENGINEERS. 2009: 759–764
View details for Web of Science ID 000286415600101
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PHASE LOCK LOOP BASED TEMPERATURE COMPENSATION FOR MEMS OSCILLATORS
22nd International Conference on Micro Electro Mechanical Systems (MEMS)
IEEE. 2009: 661–664
View details for Web of Science ID 000341431500165
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WAFER SCALE ENCAPSULATION OF LARGE LATERAL DEFLECTION MEMS STRUCTURES
22nd International Conference on Micro Electro Mechanical Systems (MEMS)
IEEE. 2009: 745–748
View details for Web of Science ID 000341431500186
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Acceleration insensitive encapsulated silicon microresonator
APPLIED PHYSICS LETTERS
2008; 93 (23)
View details for DOI 10.1063/1.3036536
View details for Web of Science ID 000261699700087
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Temperature dependence of quality factor in MEMS resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2008; 17 (3): 755-766
View details for DOI 10.1109/JMEMS.2008.924253
View details for Web of Science ID 000256626300023
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Mission results for Sapphire, a student-built satellite
ACTA ASTRONAUTICA
2008; 62 (8-9): 521-538
View details for DOI 10.1016/j.actaastro.2008.01.009
View details for Web of Science ID 000255445100008
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A study of electrostatic force nonlinearities in resonant microstructures
APPLIED PHYSICS LETTERS
2008; 92 (10)
View details for DOI 10.1063/1.2834707
View details for Web of Science ID 000253989300168
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Thermal isolation of encapsulated MEMS resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2008; 17 (1): 175-184
View details for DOI 10.1109/JMEMS.2007.904332
View details for Web of Science ID 000253259600020
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Exploring the Limits and Practicality of Q-based Temperature Compensation for Silicon Resonators
IEEE International Electron Devices Meeting
IEEE. 2008: 671–674
View details for Web of Science ID 000265829300156
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Variable thermal resistors (VTR) for thermal management of chip scale atomic clocks (CSAC)
21st IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2008)
IEEE. 2008: 852–855
View details for Web of Science ID 000253356900213
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Identification and management of diffusion pathways in polysilicon encapsulation for MEMS devices
21st IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2008)
IEEE. 2008: 104–107
View details for Web of Science ID 000253356900026
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Limits of quality factor in bulk-mode micromechanical resonators
21st IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2008)
IEEE. 2008: 74–77
View details for Web of Science ID 000253356900019
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Ultraminiature encapsulated accelerometers as a fully implantable sensor for implantable hearing aids
13th International Conference on Solid-State Sensors, Actuators and Microsystems
SPRINGER. 2007: 939–49
Abstract
Experiments were conducted to evaluate a silicon accelerometer as an implantable sound sensor for implantable hearing aids. The main motivation of this study is to find an alternative sound sensor that is implantable inside the body, yet does not suffer from the signal attenuation from the body. The merit of the accelerometer sensor as a sound sensor will be that it will utilize the natural mechanical conduction in the middle ear as a source of the vibration. With this kind of implantable sound sensor, a totally implantable hearing aid is feasible. A piezoresistive silicon accelerometer that is completely encapsulated with a thin silicon film and long flexible flex-circuit electrical cables were used for this study. The sensor is attached on the middle ear ossicles and measures the vibration transmitted from the tympanic membrane due to the sound in the ear canal. In this study, the sensor is fully characterized on a human cadaveric temporal bone preparation.
View details for DOI 10.1007/s10544-007-9072-4
View details for Web of Science ID 000250462200019
View details for PubMedID 17574533
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Scaling of amplitude-frequency-dependence nonlinearities in electrostatically transduced microresonators
JOURNAL OF APPLIED PHYSICS
2007; 102 (7)
View details for DOI 10.1063/1.2785018
View details for Web of Science ID 000250147700148
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High resolution microresonator-based digital temperature sensor
APPLIED PHYSICS LETTERS
2007; 91 (7)
View details for DOI 10.1063/1.2768629
View details for Web of Science ID 000248866600117
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Using the temperature dependence of resonator quality factor as a thermometer
APPLIED PHYSICS LETTERS
2007; 91 (1)
View details for DOI 10.1063/1.2753758
View details for Web of Science ID 000247819700074
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Temperature-compensated high-stability silicon resonators
APPLIED PHYSICS LETTERS
2007; 90 (24)
View details for DOI 10.1063/1.2748092
View details for Web of Science ID 000247305400116
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A multiaxis force sensor for the study of insect biomechanics
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2007; 16 (3): 709-718
View details for DOI 10.1109/JMEMS.2007.893677
View details for Web of Science ID 000247219200025
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Frequency stability of wafer-scale film encapsulated silicon based MEMS resonators
SENSORS AND ACTUATORS A-PHYSICAL
2007; 136 (1): 125-131
View details for DOI 10.1016/j.sna.2006.10.040
View details for Web of Science ID 000246463000014
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Wafer-scale fabrication of infrared detectors based on tunneling displacement transducers
SENSORS AND ACTUATORS A-PHYSICAL
2007; 134 (2): 575-581
View details for DOI 10.1016/j.sna.2005.07.028
View details for Web of Science ID 000245319900038
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Inhibition of metalloprotease botulinum serotype A from a pseudo-peptide binding mode to a small molecule that is active in primary neurons
JOURNAL OF BIOLOGICAL CHEMISTRY
2007; 282 (7): 5004-5014
Abstract
An efficient research strategy integrating empirically guided, structure-based modeling and chemoinformatics was used to discover potent small molecule inhibitors of the botulinum neurotoxin serotype A light chain. First, a modeled binding mode for inhibitor 2-mercapto-3-phenylpropionyl-RATKML (K(i) = 330 nM) was generated, and required the use of a molecular dynamic conformer of the enzyme displaying the reorientation of surface loops bordering the substrate binding cleft. These flexible loops are conformationally variable in x-ray crystal structures, and the model predicted that they were pivotal for providing complementary binding surfaces and solvent shielding for the pseudo-peptide. The docked conformation of 2-mercapto-3-phenylpropionyl-RATKML was then used to refine our pharmacophore for botulinum serotype A light chain inhibition. Data base search queries derived from the pharmacophore were employed to mine small molecule (non-peptidic) inhibitors from the National Cancer Institute's Open Repository. Four of the inhibitors possess K(i) values ranging from 3.0 to 10.0 microM. Of these, NSC 240898 is a promising lead for therapeutic development, as it readily enters neurons, exhibits no neuronal toxicity, and elicits dose-dependent protection of synaptosomal-associated protein (of 25 kDa) in a primary culture of embryonic chicken neurons. Isothermal titration calorimetry showed that the interaction between NSC 240898 and the botulinum A light chain is largely entropy-driven, and occurs with a 1:1 stoichiometry and a dissociation constant of 4.6 microM.
View details for DOI 10.1074/jbc.M608166200
View details for Web of Science ID 000244482000083
View details for PubMedID 17092934
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Acceleration sensitivity in beam-type electrostatic microresonators
APPLIED PHYSICS LETTERS
2007; 90 (1)
View details for DOI 10.1063/1.2426884
View details for Web of Science ID 000243379900112
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Investigating the role of orientation angle on gecko, setae adhesion using a dual-axis MEMS force sensor
14th International Conference on Solid-State Sensors, Actuators and Microsystems/21st European Conference on Solid-State Transducers
IEEE. 2007
View details for Web of Science ID 000249603700563
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Composite flexural-mode resonator with controllable turnover temperature
20th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2007)
IEEE. 2007: 378–381
View details for Web of Science ID 000255867800095
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Using MEMS to build the device and the package
14th International Conference on Solid-State Sensors, Actuators and Microsystems/21st European Conference on Solid-State Transducers
IEEE. 2007
View details for Web of Science ID 000249603700078
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CMOS compatible wafer-scale encapsulation with MEMS resonators
ASME InterPACK Conference
AMER SOC MECHANICAL ENGINEERS. 2007: 499–504
View details for Web of Science ID 000254115600065
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Si-SiO2 composite MEMS resonators in CMOS compatible wafer-scale thin-film encapsulation
Joint IEEE International Frequency Control Symposium/21st European Frequency and Time Forum
IEEE, ELECTRON DEVICES SOC & RELIABILITY GROUP. 2007: 1214–1219
View details for Web of Science ID 000252304500254
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Non-isothermal micromechanical resonators
20th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2007)
IEEE. 2007: 714–717
View details for Web of Science ID 000255867800179
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Impact of miniaturization on the current handling of electrostatic MEMS resonators
20th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2007)
IEEE. 2007: 530–533
View details for Web of Science ID 000255867800133
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An improved method of thermal resistance measurement for variable thermal resistors
ASME InterPACK Conference
AMER SOC MECHANICAL ENGINEERS. 2007: 249–253
View details for Web of Science ID 000254115600034
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Cmos-compatible dual-resonator mems temperature sensor with milli-degree accuracy
14th International Conference on Solid-State Sensors, Actuators and Microsystems/21st European Conference on Solid-State Transducers
IEEE. 2007
View details for Web of Science ID 000249603700054
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A high-stability MEMS frequency reference
14th International Conference on Solid-State Sensors, Actuators and Microsystems/21st European Conference on Solid-State Transducers
IEEE. 2007
View details for Web of Science ID 000249603700322
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Long-term and accelerated life testing of a novel single-wafer vacuum encapsulation for MEMS resonators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2006; 15 (6): 1446-1456
View details for DOI 10.1109/JMEMS.2006.883586
View details for Web of Science ID 000242983300004
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Engineering MEMS resonators with low thermoelastic damping
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2006; 15 (6): 1437-1445
View details for DOI 10.1109/JMEMS.2006.883573
View details for Web of Science ID 000242983300003
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Optimal drive condition for nonlinearity reduction in electrostatic microresonators
APPLIED PHYSICS LETTERS
2006; 89 (21)
View details for DOI 10.1063/1.2388886
View details for Web of Science ID 000242220000087
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Impact of geometry on thermoelastic dissipation in micromechanical resonant beams
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2006; 15 (4): 927-934
View details for DOI 10.1109/JMEMS.2006.879374
View details for Web of Science ID 000239712600023
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A hybrid method for bubble geometry reconstruction in two-phase microchannels
EXPERIMENTS IN FLUIDS
2006; 40 (6): 847-858
View details for DOI 10.1007/s00348-006-0123-z
View details for Web of Science ID 000239549100003
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Encapsulated submillimeter piezoresistive accelerometers
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2006; 15 (3): 507-514
View details for DOI 10.1109/JMEMS.2006.876648
View details for Web of Science ID 000238311000007
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Two-phase microfluidics for semiconductor circuits and fuel cells
HEAT TRANSFER ENGINEERING
2006; 27 (4): 53-63
View details for DOI 10.1080/01457630500523816
View details for Web of Science ID 000236239500006
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Advanced cooling technologies for microprocessors
Workshop on Frontiers in Electronics (WOFE-04)
WORLD SCIENTIFIC PUBL CO PTE LTD. 2006: 301–313
View details for Web of Science ID 000241022300016
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Temperature dependence of quality factor in MEMS resonators
19th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2006)
IEEE. 2006: 590–593
View details for Web of Science ID 000236994500148
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Wafer Scale Encapsulation of Wide Gaps using oxidation of Sacrificial Beams
31st IEEE/CPMT International Electronic Manufacturing Technology Symposium
IEEE. 2006: 300–306
View details for Web of Science ID 000264172700048
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Temperature compensation of a MEMS resonator using quality factor as a thermometer
19th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2006)
IEEE. 2006: 222–225
View details for Web of Science ID 000236994500056
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Nonlinear characterization of electrostatic MEMS resonators
IEEE International Frequency Control Symposium and Exposition
IEEE. 2006: 209–212
View details for Web of Science ID 000243684700037
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Effects of mechanical vibrations and bias voltage noise on phase noise of MEMS resonator based oscillators
19th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2006)
IEEE. 2006: 154–157
View details for Web of Science ID 000236994500039
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Phase change phenomena in silicon microchannels
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
2005; 48 (8): 1572-1582
View details for DOI 10.1016/j.ijheatmasstransfer.2004.09.048
View details for Web of Science ID 000228228400015
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Sub-mm encapsulated accelerometers: A fully implantable sensor for cochlear implants
13th International Conference on Solid-State Sensors, Actuators and Microsystems
IEEE. 2005: 109–112
View details for Web of Science ID 000232189100028
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Two-phase microfluidics for semiconductor circuits and fuel cells
3rd International Conference on Microchannels and Minichannels
AMER SOC MECHANICAL ENGINEERS. 2005: 49–58
View details for Web of Science ID 000243025300006
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Study of high speed acoustic separation in micro channels using mu-PIV
8th International Conference on Miniaturized Systems for Chemistry and Life Sciences
SPRINGER. 2005: 12–14
View details for Web of Science ID 000228997000004
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Impact of slot location on thermoelastic dissipation in micromechanical resonators
13th International Conference on Solid-State Sensors, Actuators and Microsystems
IEEE. 2005: 597–600
View details for Web of Science ID 000232189100145
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Frequency stability of wafer-scale encapsulated MEMS resonators
13th International Conference on Solid-State Sensors, Actuators and Microsystems
IEEE. 2005: 1965–1968
View details for Web of Science ID 000232189100487
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Effects of stress on the temperature coefficient of frequency in double clamped resonators
13th International Conference on Solid-State Sensors, Actuators and Microsystems
IEEE. 2005: 392–395
View details for Web of Science ID 000232189100095
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Hydrogen diffusion and pressure control of encapsulated MEMS resonators
13th International Conference on Solid-State Sensors, Actuators and Microsystems
IEEE. 2005: 920–923
View details for Web of Science ID 000232189100225
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Fully encapsulated sub-millimeter accelerometers
18th IEEE International Conference on Micro Electro Mechanical Systems (MEMS)
IEEE. 2005: 347–350
View details for Web of Science ID 000228430000086
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Non-linearity cancellation in MEMS resonators for improved power-handling
IEEE International Electron Devices Meeting
IEEE. 2005: 295–298
View details for Web of Science ID 000236225100066
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Micromachined jets for liquid impingement cooling of VLSI chips (vol 13, pg 833, 2004)
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2004; 13 (6): 1072-1072
View details for DOI 10.1109/JMEMS.2004.840851
View details for Web of Science ID 000225515100022
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Micromachined jets for liquid impingement cooling of VLSI chips
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2004; 13 (5): 833-842
View details for DOI 10.1109/JMEMS.2004.835768
View details for Web of Science ID 000224413100014
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Comparison of thermal and piezoresistive sensing approaches for atomic force microscopy topography measurements
APPLIED PHYSICS LETTERS
2004; 85 (11): 2086-2088
View details for DOI 10.1063/1.1787160
View details for Web of Science ID 000223923300073
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Fatigue crack growth in micro-machined single-crystal silicon
JOURNAL OF MATERIALS RESEARCH
2004; 19 (9): 2635-2640
View details for DOI 10.1557/JMR.2004.0343
View details for Web of Science ID 000223689000017
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Nucleation and growth of vapor bubbles in a heated silicon microchannel
JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME
2004; 126 (4): 497-497
View details for Web of Science ID 000223989100004
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Measurement system for low force and small displacement contacts
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2004; 13 (2): 220-229
View details for Web of Science ID 000220759300008
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Development and characterization of a TES optical imaging array for astrophysics applications
10th International Workshop on Low Temperature Detectors
ELSEVIER SCIENCE BV. 2004: 533–36
View details for DOI 10.1016/j.nima.2003.11.307
View details for Web of Science ID 000220606900143
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High speed particles separation using ultrasound for microTAS and lab-on-a-chip application.
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference
2004; 4: 2631-2634
Abstract
Engineers have long envisioned that a handheld portable blood diagnosis device would be able to give an accurate measurement of chemical content based on a very small sample in the shortest time possible. One of the immediate applications of such device is the point of care (POC) diagnosis system, whereby a single drop of human blood would determine his health status. However, a major technical challenge lies in the ability to separate different particles, which in the case of human blood, is to separate red and white blood cells and plasma in a quick, cheap, reliable device with low power consumption. In this paper, we present some preliminary results from our tests of ultrasound standing waves as a potential separation mechanism for blood cells. Also, we report on the study of the behavior of suspended particles of the size equivalent to a human cell under the influence of ultrasonic acoustic field, using micro particle image velocimetry (PIV) measurement technique. This provides the fundamental understanding and foundation of designing an integrated microchannel structure that can provide ultrasonic cell separation in the microscale regime. The study has shown promising results of successfully separating two different particles based on their sizes difference.
View details for PubMedID 17270815
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High speed particles separation using ultrasound for micro-TAS and lab-on-a-chip application
26th Annual International Conference of the IEEE-Engineering-in-Medicine-and-Biology-Society
IEEE. 2004: 2631–2634
View details for Web of Science ID 000225461800681
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Fundamental noise in MEMS force sensors
Conference on Noise and Information in Nanoelectronics, Sensors and Standards II
SPIE-INT SOC OPTICAL ENGINEERING. 2004: 143–151
View details for DOI 10.1117/12.549814
View details for Web of Science ID 000223225600017
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Measurements of cooling by room-temperature thermionic emission across a nanometer gap
JOURNAL OF APPLIED PHYSICS
2003; 94 (7): 4690-4696
View details for DOI 10.1063/1.1606852
View details for Web of Science ID 000185420900071
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Stress wave interference effects during fracture of silicon micromachined specimens
EXPERIMENTAL MECHANICS
2003; 43 (3): 317-322
View details for Web of Science ID 000185166800011
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Single wafer encapsulation of MEMS devices
IEEE TRANSACTIONS ON ADVANCED PACKAGING
2003; 26 (3): 227-232
View details for DOI 10.1109/TADVP.2003.818062
View details for Web of Science ID 000185862400003
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Design of piezoresistive MEMS-based accelerometer for integration with wireless sensing unit for structural monitoring
JOURNAL OF AEROSPACE ENGINEERING
2003; 16 (3): 108-114
View details for DOI 10.1016/(ASCE)0893-1321(2003)16:3(108)
View details for Web of Science ID 000183657900002
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Design of large deflection electrostatic actuators
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2003; 12 (3): 335-343
View details for DOI 10.1109/JMEMS.2003.811750
View details for Web of Science ID 000183356300013
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Piezoresistive cantilevers and measurement system for characterizing low force electrical contacts
SENSORS AND ACTUATORS A-PHYSICAL
2003; 104 (1): 68-77
View details for DOI 10.1016/S0924-4247(02)00485-5
View details for Web of Science ID 000181236100011
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Embedment of structural monitoring algorithms in a wireless sensing unit
STRUCTURAL ENGINEERING AND MECHANICS
2003; 15 (3): 285-297
View details for Web of Science ID 000181569500002
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On-chip coupling of isoelectric focusing and free solution electrophoresis for multidimensional separations
ANALYTICAL CHEMISTRY
2003; 75 (5): 1180-1187
Abstract
We have developed an acrylic microfluidic device that sequentially couples liquid-phase isoelectric focusing (IEF) and free solution capillary electrophoresis (CE). Rapid separation (<1 min) and preconcentration (73x) of species were achieved in the initial IEF dimension. Using full-field fluorescence imaging, we observed nondispersive mobilization velocities on the order of 20 microm/s during characterization of the IEF step. This transport behavior allowed controlled electrokinetic mobilization of focused sample bands to a channel junction, where voltage switching was used to repeatedly inject effluent from the IEF dimension into an ampholyte-based CE separation. This second dimension was capable of analyzing all fluid volumes of interest from the IEF dimension, as IEF was 'parked' during each CE analysis and refocused prior to additional CE analyses. Investigation of each dimension of the integrated system showed time-dependent species displacement and band-broadening behavior consistent with IEF and CE, respectively. The peak capacity of the 2D system was approximately 1300. A comprehensive 2D analysis of a fluid volume spanning 15% of the total IEF channel length was completed in less than 5 min.
View details for DOI 10.1021/ac026239a
View details for Web of Science ID 000181259300027
View details for PubMedID 12641239
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Closed-loop cooling technologies for microprocessors
IEEE International Electron Devices Meeting
IEEE. 2003: 775–778
View details for Web of Science ID 000189158800177
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Two-tiered wireless sensor network architecture for structural health monitoring
Smart Structures and Materials 2003 Conference
SPIE-INT SOC OPTICAL ENGINEERING. 2003: 8–19
View details for Web of Science ID 000185394400003
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Experimental study on two-phase heat transfer in microchannel heat sinks with hotspots
19th Annual IEEE Semiconductor Thermal Measurement and Management Symposium
IEEE. 2003: 242–246
View details for Web of Science ID 000182024200038
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Statistical damage detection using time series analysis on a structural health monitoring benchmark problem
9th International Conference on Applications of Statistics and Probability in Civil Engineering
MILLPRESS SCIENCE PUBLISHERS. 2003: 581–587
View details for Web of Science ID 000189453300078
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UV-IR science prospects with TES imaging arrays
Workshop on Hubbles Science Legacy - Future Optical/Ultraviolet Astronomy from Space
ASTRONOMICAL SOC PACIFIC. 2003: 399–402
View details for Web of Science ID 000183133000061
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Small insect measurements using a custom MEMS force sensor
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 1039–1042
View details for Web of Science ID 000184567300261
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Wafer-scale film encapsulation of micromachined accelerometers
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 1903–1906
View details for Web of Science ID 000184567300478
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Wafer scale encapsulation of MEMS devices
International Electronic Packaging Technical Conference
AMER SOC MECHANICAL ENGINEERS. 2003: 209–212
View details for Web of Science ID 000222624900033
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Investigation of energy loss mechanisms in micromechanical resonators
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 332–335
View details for Web of Science ID 000184567300083
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Mass-loaded cantilevers with suppressed higher-order modes for magnetic resonance force microscopy
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 1120–1123
View details for Web of Science ID 000184567300281
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Development of superconducting transition edge sensors for time and energy resolved single photon counters with application to imaging astronomy
Conference on Materials for Infrared Detectors III
SPIE-INT SOC OPTICAL ENGINEERING. 2003: 192–200
View details for Web of Science ID 000188460600018
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Silicon electroosmotic micropumps for integrated circuit thermal management
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 151–154
View details for Web of Science ID 000184567300038
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Hard X-ray polarimetry with the Ramaty High Energy Solar Spectroscopic Imager (RHESSI)
Conference on Polarimetry in Astronomy
SPIE-INT SOC OPTICAL ENGINEERING. 2003: 8–19
View details for Web of Science ID 000181847200002
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Process compatible polysilicon-based electrical through-wafer interconnects in silicon substrates
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2002; 11 (6): 631-640
View details for DOI 10.1109/JMEMS.2002.805206
View details for Web of Science ID 000179740900002
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Design of atomic force microscope cantilevers for combined thermomechanical writing and thermal reading in array operation
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2002; 11 (6): 765-774
View details for DOI 10.1109/JMEMS.2002.803283
View details for Web of Science ID 000179740900017
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Vacuum thermionic refrigeration with a semiconductor heterojunction structure
APPLIED PHYSICS LETTERS
2002; 81 (22): 4242-4244
View details for DOI 10.1063/1.1523653
View details for Web of Science ID 000179340800048
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Evidence for van der Waals adhesion in gecko setae
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2002; 99 (19): 12252-12256
Abstract
Geckos have evolved one of the most versatile and effective adhesives known. The mechanism of dry adhesion in the millions of setae on the toes of geckos has been the focus of scientific study for over a century. We provide the first direct experimental evidence for dry adhesion of gecko setae by van der Waals forces, and reject the use of mechanisms relying on high surface polarity, including capillary adhesion. The toes of live Tokay geckos were highly hydrophobic, and adhered equally well to strongly hydrophobic and strongly hydrophilic, polarizable surfaces. Adhesion of a single isolated gecko seta was equally effective on the hydrophobic and hydrophilic surfaces of a microelectro-mechanical systems force sensor. A van der Waals mechanism implies that the remarkable adhesive properties of gecko setae are merely a result of the size and shape of the tips, and are not strongly affected by surface chemistry. Theory predicts greater adhesive forces simply from subdividing setae to increase surface density, and suggests a possible design principle underlying the repeated, convergent evolution of dry adhesive microstructures in gecko, anoles, skinks, and insects. Estimates using a standard adhesion model and our measured forces come remarkably close to predicting the tip size of Tokay gecko seta. We verified the dependence on size and not surface type by using physical models of setal tips nanofabricated from two different materials. Both artificial setal tips stuck as predicted and provide a path to manufacturing the first dry, adhesive microstructures.
View details for DOI 10.1073/pnas.192252799
View details for Web of Science ID 000178187000048
View details for PubMedID 12198184
View details for PubMedCentralID PMC129431
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Closed-loop electroosmotic microchannel cooling system for VLSI circuits
17th Annual IEEE Semiconductor Thermal Measurement and Management Symposium
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. 2002: 347–55
View details for DOI 10.1109/TCAPT.2002.800599
View details for Web of Science ID 000180333200003
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Subcritical crack growth in single-crystal silicon using micromachined specimens
JOURNAL OF MATERIALS RESEARCH
2002; 17 (3): 683-692
View details for Web of Science ID 000174300000027
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Measurements and modeling of two-phase flow in microchannels with nearly constant heat flux boundary conditions
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2002; 11 (1): 12-19
View details for Web of Science ID 000173751000002
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Characterization of a two-dimensional cantilever array with through-wafer electrical interconnects
APPLIED PHYSICS LETTERS
2002; 80 (4): 664-666
View details for Web of Science ID 000173508900044
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A wireless modular monitoring system for civil structures
20th IMAC Conference on Structural Dynamics
SOC EXPERIMENTAL MECHANICS INC. 2002: 1–6
View details for Web of Science ID 000176646000001
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Transient and sub-atmospheric performance of a closed-loop electroosmotic microchannel cooling system
THERMES 2002 International Conference
MILLPRESS SCIENCE PUBLISHERS. 2002: 133–139
View details for Web of Science ID 000181956000016
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Enhanced nucleate boiling in microchannels
15th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2002)
IEEE. 2002: 89–92
View details for Web of Science ID 000174908700022
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Validation of a wireless modular monitoring system for structures
Smart Structures and Materials 2002 Conference
SPIE-INT SOC OPTICAL ENGINEERING. 2002: 124–135
View details for Web of Science ID 000177732300013
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E-cadherin extra-cellular domain interaction examined by atomic force microscopy
CELL PRESS. 2002: 55A–55A
View details for Web of Science ID 000173252700273
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Electron spin relaxation near a micron-size ferromagnet
PHYSICAL REVIEW LETTERS
2001; 87 (27)
Abstract
Magnetic resonance force microscopy was used to study the behavior of small ensembles of unpaired electron spins in silica near a micrometer-size ferromagnetic tip. Using a cantilever-driven spin manipulation protocol and a magnetic field gradient greater than 10(5) T/m, signals from as few as 100 net spins within a 20 nm thick resonant slice could be studied. A sixfold increase in the spin-lattice relaxation rate was found within 800 nm of the ferromagnet, while no effect due to silica surface proximity was detected. The results are interpreted in terms of Larmor-frequency magnetic field fluctuations emanating from the ferromagnet.
View details for DOI 10.1103/PhysRevLett.87.277602
View details for Web of Science ID 000173040800056
View details for PubMedID 11800915
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A high-precision, wide-bandwidth micromachined tunneling accelerometer
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2001; 10 (3): 425-433
View details for Web of Science ID 000170875900012
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A high-stiffness axial resonant probe for atomic force microscopy
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2001; 10 (3): 434-441
View details for Web of Science ID 000170875900013
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Noncontact friction and force fluctuations between closely spaced bodies
PHYSICAL REVIEW LETTERS
2001; 87 (9)
Abstract
Noncontact friction between a Au(111) surface and an ultrasensitive gold-coated cantilever was measured as a function of tip-sample spacing, temperature, and bias voltage using observations of cantilever damping and Brownian motion. The importance of the inhomogeneous contact potential is discussed and comparison is made to measurements over dielectric surfaces. Using the fluctuation-dissipation theorem, the force fluctuations are interpreted in terms of near-surface fluctuating electric fields interacting with static surface charge.
View details for DOI 10.1103/PhysRevLett.87.096801
View details for Web of Science ID 000170698000030
View details for PubMedID 11531586
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Nanometer-Scale Force Sensing with MEMS Devices
IEEE SENSORS JOURNAL
2001; 1 (2): 148-157
View details for DOI 10.1109/JSEN.2001.936932
View details for Web of Science ID 000208325600006
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Refrigeration by combined tunneling and thermionic emission in vacuum: Use of nanometer scale design
APPLIED PHYSICS LETTERS
2001; 78 (17): 2572-2574
View details for Web of Science ID 000168304600053
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Magnetic dissipation and fluctuations in individual nanomagnets measured by ultrasensitive cantilever magnetometry
PHYSICAL REVIEW LETTERS
2001; 86 (13): 2874-2877
Abstract
Cantilever magnetometry with moment resolution better than 10(4)micro(B) was used to study individual nanomagnets. By using the fluctuation-dissipation theorem to interpret measurements of field-induced cantilever damping, the low frequency spectral density of magnetic fluctuations could be determined with resolution better than 1micro(B) Hz-1/2. Cobalt nanowires exhibited significant magnetic dissipation and the associated magnetic fluctuations were found to have 1/f frequency dependence. In individual submicron rare-earth alloy magnets, the dissipation/fluctuation was very small and not distinguishable from that of a bare silicon cantilever.
View details for Web of Science ID 000167693000044
View details for PubMedID 11290061
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Optimization of turn geometries for microchip electrophoresis
ANALYTICAL CHEMISTRY
2001; 73 (6): 1350-1360
View details for Web of Science ID 000167546400042
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Adventures in attonewton force detection
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
2001; 72: S3-S10
View details for DOI 10.1007/s003390100729
View details for Web of Science ID 000205245800002
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Atomic force microscope cantilevers for combined thermomechanical data writing and reading
APPLIED PHYSICS LETTERS
2001; 78 (9): 1300-1302
View details for Web of Science ID 000167151000044
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A micromachined silicon low-voltage parallel-plate electrokinetic pump
11th International Conference on Solid-State Sensors and Actuators
SPRINGER-VERLAG BERLIN. 2001: 920–923
View details for Web of Science ID 000172547800211
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Two-phase microchannel heat sinks for an electrokinetic VLSI chip cooling system
17th Annual IEEE Semiconductor Thermal Measurement and Management Symposium
IEEE. 2001: 153–157
View details for Web of Science ID 000168411800021
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Low force electrical contact measurements using piezoresistive MEMS cantilevers to characterize thin-film metallization
11th International Conference on Solid-State Sensors and Actuators
SPRINGER-VERLAG BERLIN. 2001: 1032–1035
View details for Web of Science ID 000172547800237
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New thin film epitaxial polysilicon encapsulation for piezoresistive accelerometers
14th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2001)
IEEE. 2001: 54–59
View details for Web of Science ID 000166833600014
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Modeling of two-phase microchannel heat sinks for VLSI chips
14th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2001)
IEEE. 2001: 422–426
View details for Web of Science ID 000166833600102
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Performance characterization of ultra-thin n-type piezoresistive cantilevers
11th International Conference on Solid-State Sensors and Actuators
SPRINGER-VERLAG BERLIN. 2001: 998–1001
View details for Web of Science ID 000172547800229
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Exploring insect biomechanics with micromachined force sensors
11th International Conference on Solid-State Sensors and Actuators
SPRINGER-VERLAG BERLIN. 2001: 1662–1665
View details for Web of Science ID 000172547800386
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A micromachined magnetic-field sensor based on an electron tunneling displacement transducer
SENSORS AND ACTUATORS A-PHYSICAL
2000; 86 (1-2): 8-20
View details for Web of Science ID 000090127700002
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Adhesive force of a single gecko foot-hair
NATURE
2000; 405 (6787): 681-685
Abstract
Geckos are exceptional in their ability to climb rapidly up smooth vertical surfaces. Microscopy has shown that a gecko's foot has nearly five hundred thousand keratinous hairs or setae. Each 30-130 microm long seta is only one-tenth the diameter of a human hair and contains hundreds of projections terminating in 0.2-0.5 microm spatula-shaped structures. After nearly a century of anatomical description, here we report the first direct measurements of single setal force by using a two-dimensional micro-electromechanical systems force sensor and a wire as a force gauge. Measurements revealed that a seta is ten times more effective at adhesion than predicted from maximal estimates on whole animals. Adhesive force values support the hypothesis that individual seta operate by van der Waals forces. The gecko's peculiar behaviour of toe uncurling and peeling led us to discover two aspects of setal function which increase their effectiveness. A unique macroscopic orientation and preloading of the seta increased attachment force 600-fold above that of frictional measurements of the material. Suitably orientated setae reduced the forces necessary to peel the toe by simply detaching above a critical angle with the substratum.
View details for Web of Science ID 000087465800046
View details for PubMedID 10864324
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1/F noise considerations for the design and process optimization of piezoresistive cantilevers
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2000; 9 (2): 226-235
View details for Web of Science ID 000087842600008
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Fracture toughness and crack growth phenomena of plasma-etched single crystal silicon
10th International Conference on Solid-State Sensors and Actuators
ELSEVIER SCIENCE SA. 2000: 194–99
View details for Web of Science ID 000087144800031
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Packaging a piezoresistive pressure sensor to measure low absolute pressures over a wide sub-zero temperature range
10th International Conference on Solid-State Sensors and Actuators
ELSEVIER SCIENCE SA. 2000: 142–49
View details for Web of Science ID 000087144800023
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Rapid biochemical detection and differentiation with magnetic force microscope cantilever arrays
10th International Conference on Solid-State Sensors and Actuators
ELSEVIER SCIENCE SA. 2000: 256–62
View details for Web of Science ID 000087144800041
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Integration of through-wafer interconnects with a two-dimensional cantilever array
10th International Conference on Solid-State Sensors and Actuators
ELSEVIER SCIENCE SA. 2000: 118–23
View details for Web of Science ID 000087144800019
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Electroosmotic capillary flow with nonuniform zeta potential
Analytical chemistry
2000; 72 (5): 1053-7
Abstract
The present work is an analytical and experimental study of electroosmotic flow (EOF) in cylindrical capillaries with nonuniform wall surface charge (zeta-potential) distributions. In particular, this study investigates perturbations of electroosmotic flow in open capillaries that are due to induced pressure gradients resulting from axial variations in the wall zeta-potential. The experimental inquiry focuses on electroosmotic flow under a uniform applied field in capillaries with an EOF-suppressing polymer adsorbed onto various fractions of the total capillary length. This fractional EOF suppression was achieved by coupling capillaries with substantially different zeta-potentials. The resulting flow fields were imaged with a nonintrusive, caged-fluorescence imaging technique. Simple analytical models for the velocity field and rate of sample dispersion in capillaries with axial zeta-potential variations are presented. The resulting induced pressure gradients and the associated band-broadening effects are of particular importance to the performance of chemical and biochemical analysis systems such as capillary electrokinetic chromatography and capillary zone electrophoresis.
View details for PubMedID 10739211
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Electroosmotic capillary flow with nonuniform zeta potential
ANALYTICAL CHEMISTRY
2000; 72 (5): 1053-1057
Abstract
The present work is an analytical and experimental study of electroosmotic flow (EOF) in cylindrical capillaries with nonuniform wall surface charge (zeta-potential) distributions. In particular, this study investigates perturbations of electroosmotic flow in open capillaries that are due to induced pressure gradients resulting from axial variations in the wall zeta-potential. The experimental inquiry focuses on electroosmotic flow under a uniform applied field in capillaries with an EOF-suppressing polymer adsorbed onto various fractions of the total capillary length. This fractional EOF suppression was achieved by coupling capillaries with substantially different zeta-potentials. The resulting flow fields were imaged with a nonintrusive, caged-fluorescence imaging technique. Simple analytical models for the velocity field and rate of sample dispersion in capillaries with axial zeta-potential variations are presented. The resulting induced pressure gradients and the associated band-broadening effects are of particular importance to the performance of chemical and biochemical analysis systems such as capillary electrokinetic chromatography and capillary zone electrophoresis.
View details for Web of Science ID 000085605100043
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Quality factors in micron- and submicron-thick cantilevers
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2000; 9 (1): 117-125
View details for Web of Science ID 000085857600017
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Designing corner compensation for electrophoresis in compact geometries
4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000)
SPRINGER. 2000: 287–290
View details for Web of Science ID 000167335400065
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Miniaturized capillary isoelectric focusing (cIEF): Towards a portable high-speed separation method
4th International Symposium on Micro Total Analysis Systems ((mu)TAS 2000)
SPRINGER. 2000: 367–370
View details for Web of Science ID 000167335400085
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Experimental investigation of flow transition in microchannels using micron-resolution particle image velocimetry
7th Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems
IEEE. 2000: 148–153
View details for Web of Science ID 000089141400023
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High-resolution measurement of crack growth in micro-machined single crystal silicon
Symposium MM on Materials Science of Microelectromechanical Systems (MEMS) Devices II held at the 1999 MRS Fall Meeting
MATERIALS RESEARCH SOCIETY. 2000: 43–48
View details for Web of Science ID 000165506600007
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Silicon dopant imaging by dissipation force microscopy
APPLIED PHYSICS LETTERS
1999; 75 (18): 2785-2787
View details for Web of Science ID 000083295500027
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An integrated controller for tunnel sensors
IEEE JOURNAL OF SOLID-STATE CIRCUITS
1999; 34 (8): 1099-1107
View details for Web of Science ID 000081755500009
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High-sensitivity piezoresistive cantilevers under 1000 angstrom thick
APPLIED PHYSICS LETTERS
1999; 75 (2): 289-291
View details for Web of Science ID 000081265200047
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Intrinsic-carrier thermal runaway in silicon microcantilevers
MICROSCALE THERMOPHYSICAL ENGINEERING
1999; 3 (3): 217-228
View details for Web of Science ID 000082536200006
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Ultrahigh-density atomic force microscopy data storage with erase capability
APPLIED PHYSICS LETTERS
1999; 74 (9): 1329-1331
View details for Web of Science ID 000079010000047
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Technique for measurement of the noise of a sensor in the presence of large background signals
REVIEW OF SCIENTIFIC INSTRUMENTS
1998; 69 (7): 2767-2772
View details for Web of Science ID 000075279200030
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Characterization of a high-sensitivity micromachined tunneling accelerometer with micro-g resolution
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
1998; 7 (2): 235-244
View details for Web of Science ID 000073957900012
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Independent detection of vertical and lateral forces with a sidewall-implanted dual-axis piezoresistive cantilever
APPLIED PHYSICS LETTERS
1998; 72 (11): 1388-1390
View details for Web of Science ID 000072566000043
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Low-stiffness silicon cantilevers with integrated heaters and piezoresistive sensors for high-density AFM thermomechanical data storage
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
1998; 7 (1): 69-78
View details for Web of Science ID 000073005900009
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Sidewall-implanted dual-axis piezoresistive cantilever for AFM data storage readback and tracking
11th Annual International Workshop on Micro Electro Mechanical Systems
IEEE. 1998: 12–17
View details for Web of Science ID 000073380900003
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Numerical framework for the modeling of electrokinetic flows
Microfluidic Devices and Systems
SPIE-INT SOC OPTICAL ENGINEERING. 1998: 217–227
View details for Web of Science ID 000076705100023
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Attonewton force detection using ultrathin silicon cantilevers
APPLIED PHYSICS LETTERS
1997; 71 (2): 288-290
View details for Web of Science ID A1997XK16000047
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Fabrication of collimating grids for an x-ray solar telescope using LIGA methods
MICROSYSTEM TECHNOLOGIES
1997; 3 (3): 91-96
View details for Web of Science ID A1997YD29700001
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Torsional force probes optimized for higher order mode suppression
9th International Conference on Solid-State Sensors and Actuators
I E E E. 1997: 141–144
View details for Web of Science ID A1997BJ35B00032
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Development of a modal analysis accelerometer based on a tunneling displacement transducer
9th International Conference on Solid-State Sensors and Actuators
IEEE. 1997: 867–870
View details for Web of Science ID A1997BJ35B00211
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Wafer-scale processing, assembly, and testing of tunneling infrared detectors.
9th International Conference on Solid-State Sensors and Actuators
IEEE. 1997: 1241–1244
View details for Web of Science ID A1997BJ35B00305
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Characterization of a high-sensitivity micromachined tunneling accelerometer
9th International Conference on Solid-State Sensors and Actuators
IEEE. 1997: 471–472
View details for Web of Science ID A1997BJ35B00118
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Low frequency drift in tunnel sensors
9th International Conference on Solid-State Sensors and Actuators
IEEE. 1997: 871–874
View details for Web of Science ID A1997BJ35B00212
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Micromachined heaters with 1-mu s thermal time constants for AFM thermomechanical data storage
9th International Conference on Solid-State Sensors and Actuators
I E E E. 1997: 1085–1088
View details for Web of Science ID A1997BJ35B00265
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Low-stiffness silicon cantilevers for thermal writing and piezoresistive readback with the atomic force microscope
APPLIED PHYSICS LETTERS
1996; 69 (18): 2767-2769
View details for Web of Science ID A1996VP26500049
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A miniature, high-sensitivity, electron tunneling accelerometer
8th International Conference on Solid-State Sensors and Actuators (Eurosensors IX)
ELSEVIER SCIENCE SA. 1996: 227–31
View details for Web of Science ID A1996UV64900002
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Micromachined infrared sensors using tunneling displacement transducers
REVIEW OF SCIENTIFIC INSTRUMENTS
1996; 67 (1): 112-128
View details for Web of Science ID A1996TQ62300016
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A microfabricated electron-tunneling accelerometer as a directional underwater acoustic sensor
Workshop on Acoustic Particle Velocity Sensors - Design, Performance, and Applications
AIP PRESS. 1996: 57–68
View details for Web of Science ID A1996BF36A00004
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A mu-magnetometer based on electron tunneling
IEEE 9th Annual International Workshop on Micro Electro Mechanical Systems - An Investigation of Micro Structures, Sensors, Actuators, Machines and Systems
I E E E. 1996: 467–472
View details for Web of Science ID A1996BF27K00081
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SENSORS BASED ON TUNNELING DISPLACEMENT TRANSDUCERS - DESIGN, APPLICATIONS, AND LIMITATIONS
AMER CHEMICAL SOC. 1995: 50-COLL
View details for Web of Science ID A1995QP23201561
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Fabricating sub-collimating grids for an X-ray solar imaging spectrometer using LIGA techniques
1st Annual SPIE Conference on Microlithography and Metrology in Micromachining
SPIE - INT SOC OPTICAL ENGINEERING. 1995: 214–225
View details for Web of Science ID A1995BE24J00024
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MICROINSTRUMENTS AND MICROSENSORS FOR SPACE SCIENCE
43rd Astronautical Congress
PERGAMON-ELSEVIER SCIENCE LTD. 1994: 705–13
View details for Web of Science ID A1994QE69400009
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WIDE-BANDWIDTH ELECTROMECHANICAL ACTUATORS FOR TUNNELING DISPLACEMENT TRANSDUCERS
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
1994; 3 (3): 97-104
View details for Web of Science ID A1994RM17600002
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A MINIATURE HIGH-SENSITIVITY BROAD-BAND ACCELEROMETER BASED ON ELECTRON-TUNNELING TRANSDUCERS
7th International Conference on Solid-State Sensors and Actuators (Transducers 93)
ELSEVIER SCIENCE SA LAUSANNE. 1994: 107–14
View details for Web of Science ID A1994NT26700018
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CAPACITIVE EDGE SENSOR DESIGN FOR SELENE SEGMENTED PRIMARY MIRROR
Conference on Laser Power Beaming
SPIE - INT SOC OPTICAL ENGINEERING. 1994: 125–138
View details for Web of Science ID A1994BA43C00014
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MICROMACHINED TUNNELING DISPLACEMENT TRANSDUCERS FOR PHYSICAL SENSORS
39TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC
A V S AMER INST PHYSICS. 1993: 797–802
View details for Web of Science ID A1993LP00700014
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FABRICATION AND CHARACTERIZATION OF A MICROMACHINED DEFORMABLE MIRROR FOR ADAPTIVE OPTICS APPLICATIONS
Conference on Space Astronomical Telescopes and Instruments II
SPIE - INT SOC OPTICAL ENGINEERING. 1993: 421–430
View details for Web of Science ID A1993BZ81R00045
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ELECTRON TUNNEL SENSORS
38TH NATIONAL SYMP OF THE AMERICAN VACUUM SOC
A V S AMER INST PHYSICS. 1992: 2114–18
View details for Web of Science ID A1992JE68200120
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NOVEL POSITION SENSOR TECHNOLOGIES FOR MICROACCELEROMETERS
CONF ON SENSORS AND SENSOR SYSTEMS FOR GUIDANCE AND NAVIGATION 2
SPIE - INT SOC OPTICAL ENGINEERING. 1992: 165–172
View details for Web of Science ID A1992BW29W00018
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A MICROMACHINED SILICON ELECTRON-TUNNELING SENSOR
3RD WORKSHOP ON MICRO ELECTRO MECHANICAL SYSTEMS ( MEMS 90 )
I E E E. 1990: 192–196
View details for Web of Science ID A1990BR07N00038
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ELECTRON TUNNEL SENSOR TECHNOLOGY
CONF ON TECHNOLOGY 2000
NASA. 1990: 370–381
View details for Web of Science ID A1990BT08G00046