Yoshio Nishi
Professor (Research) of Electrical Engineering, Emeritus
Bio
Nishi's research interest has been in silicon and germanium-based CMOS devices, processes and materials. He is currently interested in research for new device structures with new materials in the nanoelectronics era, resistive switching memory, metal gate work function engineering, flexible electronics, graphene band engineering.
Honors & Awards
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Fellow, IEEE (1987)
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Life Fellow, IEEE (2014)
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Jack A. Morton Award, IEEE (1995)
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Robert N. Noyce Medal, IEEE (2002)
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Lifetme Achievement Award, SEMI (2008)
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Fellow International, Japan Society of Applied Physics (2012)
Boards, Advisory Committees, Professional Organizations
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Evaluation Committee, MANA project in NIMS (2010 - 2017)
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Technical Advisory Board, Ultratech Stepper Inc (1994 - Present)
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Board of Directors, Zeptor Inc (2012 - Present)
Professional Education
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PhD, University of Tokyo (1973)
Current Research and Scholarly Interests
resistive switching nonvolatile memory mechanism, and 2D materials and devices
2023-24 Courses
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Independent Studies (7)
- Graduate Independent Study
MATSCI 399 (Aut, Win, Spr, Sum) - Master's Research
MATSCI 200 (Aut, Win, Spr, Sum) - Ph.D. Research
MATSCI 300 (Aut, Win, Spr, Sum) - Practical Training
MATSCI 299 (Aut, Win, Spr, Sum) - Research
PHYSICS 490 (Aut, Win, Spr, Sum) - Special Studies and Reports in Electrical Engineering
EE 191 (Aut) - Special Studies or Projects in Electrical Engineering
EE 190 (Aut)
- Graduate Independent Study
All Publications
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Carbon nanotube thermoelectric devices by direct printing: Toward wearable energy converters
APPLIED PHYSICS LETTERS
2021; 118 (17)
View details for DOI 10.1063/5.0042349
View details for Web of Science ID 000677695700001
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Three-Dimensional Analysis of Particle Distribution on Filter Layers inside N95 Respirators by Deep Learning.
Nano letters
2020
Abstract
The global COVID-19 pandemic has changed many aspects of daily lives. Wearing personal protective equipment, especially respirators (face masks), has become common for both the public and medical professionals, proving to be effective in preventing spread of the virus. Nevertheless, a detailed understanding of respirator filtration-layer internal structures and their physical configurations is lacking. Here, we report three-dimensional (3D) internal analysis of N95 filtration layers via X-ray tomography. Using deep learning methods, we uncover how the distribution and diameters of fibers within these layers directly affect contaminant particle filtration. The average porosity of the filter layers is found to be 89.1%. Contaminants are more efficiently captured by denser fiber regions, with fibers <1.8 mum in diameter being particularly effective, presumably because of the stronger electric field gradient on smaller diameter fibers. This study provides critical information for further development of N95-type respirators that combine high efficiency with good breathability.
View details for DOI 10.1021/acs.nanolett.0c04230
View details for PubMedID 33283521
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Bidirectional Analog Conductance Modulation for RRAM-Based Neural Networks
IEEE TRANSACTIONS ON ELECTRON DEVICES
2020; 67 (11): 4904–10
View details for DOI 10.1109/TED.2020.3025849
View details for Web of Science ID 000584285700062
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Effect of IrO2 Spatial Distribution on the Stability and Charge Distribution of Ti1-xIrxO2 Alloys
CHEMISTRY OF MATERIALS
2019; 31 (21): 8742–51
View details for DOI 10.1021/acs.chemmater.9b02507
View details for Web of Science ID 000497262500016
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Intrinsic limits of leakage current in self-heating-triggered threshold switches
APPLIED PHYSICS LETTERS
2019; 114 (18)
View details for DOI 10.1063/1.5089261
View details for Web of Science ID 000467699000023
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Contact Engineering High-Performance n-Type MoTe2 Transistors.
Nano letters
2019
Abstract
Semiconducting MoTe2 is one of the few two-dimensional (2D) materials with a moderate band gap, similar to silicon. However, this material remains underexplored for 2D electronics due to ambient instability and predominantly p-type Fermi level pinning at contacts. Here, we demonstrate unipolar n-type MoTe2 transistors with the highest performance to date, including high saturation current (>400 μA/μm at 80 K and >200 μA/μm at 300 K) and relatively low contact resistance (1.2 to 2 kΩ·μm from 80 to 300 K), achieved with Ag contacts and AlO x encapsulation. We also investigate other contact metals (Sc, Ti, Cr, Au, Ni, Pt), extracting their Schottky barrier heights using an analytic subthreshold model. High-resolution X-ray photoelectron spectroscopy reveals that interfacial metal-Te compounds dominate the contact resistance. Among the metals studied, Sc has the lowest work function but is the most reactive, which we counter by inserting monolayer hexagonal boron nitride between MoTe2 and Sc. These metal-insulator-semiconductor (MIS) contacts partly depin the metal Fermi level and lead to the smallest Schottky barrier for electron injection. Overall, this work improves our understanding of n-type contacts to 2D materials, an important advance for low-power electronics.
View details for DOI 10.1021/acs.nanolett.9b02497
View details for PubMedID 31314531
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Contact Engineering of Trilayer Black Phosphorus With Scandium and Gold
IEEE JOURNAL OF THE ELECTRON DEVICES SOCIETY
2019; 7 (1): 322–28
View details for DOI 10.1109/JEDS.2019.2897167
View details for Web of Science ID 000460753000046
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Formation of epitaxial Hf digermanide/Ge(001) contact and its crystalline properties
JAPANESE JOURNAL OF APPLIED PHYSICS
2018; 57 (7)
View details for DOI 10.7567/JJAP.57.07MA05
View details for Web of Science ID 000439389500006
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Copper interstitial recombination centers in Cu3N
PHYSICAL REVIEW B
2018; 97 (24)
View details for DOI 10.1103/PhysRevB.97.245201
View details for Web of Science ID 000434016100006
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Transient dynamics of NbOx threshold switches explained by Poole-Frenkel based thermal feedback mechanism
APPLIED PHYSICS LETTERS
2018; 112 (19)
View details for DOI 10.1063/1.5027152
View details for Web of Science ID 000431980100044
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Research Update: Ab initio study on resistive memory device optimization trends: Dopant segregation effects and data retention in HfO2-x
APL MATERIALS
2018; 6 (5)
View details for DOI 10.1063/1.5032120
View details for Web of Science ID 000433944800008
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Effect of thermal insulation on the electrical characteristics of NbOx threshold switches
APPLIED PHYSICS LETTERS
2018; 112 (7)
View details for DOI 10.1063/1.5015941
View details for Web of Science ID 000425493600036
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HfO2/Ti Interface Mediated Conductive Filament Formation in RRAM: An Ab Initio Study
IEEE TRANSACTIONS ON ELECTRON DEVICES
2018; 65 (2): 507–13
View details for DOI 10.1109/TED.2017.2785352
View details for Web of Science ID 000423124500019
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A Bi-stable 1-/2-Transistor SRAM in 14 nm FinFET Technology for High Density / High Performance Embedded Applications
IEEE. 2018
View details for Web of Science ID 000459882300076
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Physical origins of current and temperature controlled negative differential resistances in NbO2
NATURE COMMUNICATIONS
2017; 8: 658
Abstract
Negative differential resistance behavior in oxide memristors, especially those using NbO2, is gaining renewed interest because of its potential utility in neuromorphic computing. However, there has been a decade-long controversy over whether the negative differential resistance is caused by a relatively low-temperature non-linear transport mechanism or a high-temperature Mott transition. Resolving this issue will enable consistent and robust predictive modeling of this phenomenon for different applications. Here we examine NbO2 memristors that exhibit both a current-controlled and a temperature-controlled negative differential resistance. Through thermal and chemical spectromicroscopy and numerical simulations, we confirm that the former is caused by a ~400 K non-linear-transport-driven instability and the latter is caused by the ~1000 K Mott metal-insulator transition, for which the thermal conductance counter-intuitively decreases in the metallic state relative to the insulating state.The development of future computation devices will be aided by a better understanding of the physics underlying material behaviors. Using thermoreflectance and spatially resolved X-ray microscopy, Kumar et al. elucidate the origin of two types of negative differential resistance in NbO2 memristors.
View details for PubMedID 28939848
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HfSe2 and ZrSe2: Two-dimensional semiconductors with native high-κ oxides.
Science advances
2017; 3 (8): e1700481
Abstract
The success of silicon as a dominant semiconductor technology has been enabled by its moderate band gap (1.1 eV), permitting low-voltage operation at reduced leakage current, and the existence of SiO2 as a high-quality "native" insulator. In contrast, other mainstream semiconductors lack stable oxides and must rely on deposited insulators, presenting numerous compatibility challenges. We demonstrate that layered two-dimensional (2D) semiconductors HfSe2 and ZrSe2 have band gaps of 0.9 to 1.2 eV (bulk to monolayer) and technologically desirable "high-κ" native dielectrics HfO2 and ZrO2, respectively. We use spectroscopic and computational studies to elucidate their electronic band structure and then fabricate air-stable transistors down to three-layer thickness with careful processing and dielectric encapsulation. Electronic measurements reveal promising performance (on/off ratio > 106; on current, ~30 μA/μm), with native oxides reducing the effects of interfacial traps. These are the first 2D materials to demonstrate technologically relevant properties of silicon, in addition to unique compatibility with high-κ dielectrics, and scaling benefits from their atomically thin nature.
View details for DOI 10.1126/sciadv.1700481
View details for PubMedID 28819644
View details for PubMedCentralID PMC5553816
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Ultra-thin and high-response transparent and flexible heater based on carbon nanotube film
APPLIED PHYSICS LETTERS
2017; 110 (15)
View details for DOI 10.1063/1.4978596
View details for Web of Science ID 000399689400030
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Properties of Dopants in HfOx for Improving the Performance of Nonvolatile Memory
PHYSICAL REVIEW APPLIED
2017; 7 (3)
View details for DOI 10.1103/PhysRevApplied.7.034020
View details for Web of Science ID 000399280700005
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Chemical Vapor-Deposited Hexagonal Boron Nitride as a Scalable Template for High-Performance Organic Field-Effect Transistors
CHEMISTRY OF MATERIALS
2017; 29 (5): 2341-2347
View details for DOI 10.1021/acs.chemmater.6b05517
View details for Web of Science ID 000396639400049
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Oxygen migration during resistance switching and failure of hafnium oxide memristors
APPLIED PHYSICS LETTERS
2017; 110 (10)
View details for DOI 10.1063/1.4974535
View details for Web of Science ID 000397871800046
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Extrinsic time-dependent dielectric breakdown of low-k organosilicate thin films from vacuum-ultraviolet irradiation
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
2017; 35 (2)
View details for DOI 10.1116/1.4974315
View details for Web of Science ID 000397762400035
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Polaronic interactions between oxygen vacancies in rutile TiO2
PHYSICAL REVIEW B
2017; 95 (5)
View details for DOI 10.1103/PhysRevB.95.054104
View details for Web of Science ID 000393497900002
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Spatially uniform resistance switching of low current, high endurance titanium-niobium-oxide memristors.
Nanoscale
2017; 9 (5): 1793-1798
Abstract
We analyzed micrometer-scale titanium-niobium-oxide prototype memristors, which exhibited low write-power (<3 μW) and energy (<200 fJ per bit per μm(2)), low read-power (∼nW), and high endurance (>millions of cycles). To understand their physico-chemical operating mechanisms, we performed in operando synchrotron X-ray transmission nanoscale spectromicroscopy using an ultra-sensitive time-multiplexed technique. We observed only spatially uniform material changes during cell operation, in sharp contrast to the frequently detected formation of a localized conduction channel in transition-metal-oxide memristors. We also associated the response of assigned spectral features distinctly to non-volatile storage (resistance change) and writing of information (application of voltage and Joule heating). These results provide critical insights into high-performance memristors that will aid in device design, scaling and predictive circuit-modeling, all of which are essential for the widespread deployment of successful memristor applications.
View details for DOI 10.1039/c6nr07671h
View details for PubMedID 27906408
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Formation of Epitaxial Hf Germanide/Ge Contacts for Schottky Barrier Height Engineering
IEEE. 2017: 47–48
View details for Web of Science ID 000427060000014
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Ferroelectric Switching Pathways and Energetics in (Hf,Zr)O-2
ELECTROCHEMICAL SOC INC. 2017: 107–21
View details for DOI 10.1149/07532.0107ecst
View details for Web of Science ID 000435221100011
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Conduction Channel Formation and Dissolution Due to Oxygen Thermophoresis/Diffusion in Hafnium Oxide Memristors
ACS NANO
2016; 10 (12): 11205-11210
Abstract
Transition-metal-oxide memristors, or resistive random-access memory (RRAM) switches, are under intense development for storage-class memory because of their favorable operating power, endurance, speed, and density. Their commercial deployment critically depends on predictive compact models based on understanding nanoscale physicochemical forces, which remains elusive and controversial owing to the difficulties in directly observing atomic motions during resistive switching, Here, using scanning transmission synchrotron X-ray spectromicroscopy to study in situ switching of hafnium oxide memristors, we directly observed the formation of a localized oxygen-deficiency-derived conductive channel surrounded by a low-conductivity ring of excess oxygen. Subsequent thermal annealing homogenized the segregated oxygen, resetting the cells toward their as-grown resistance state. We show that the formation and dissolution of the conduction channel are successfully modeled by radial thermophoresis and Fick diffusion of oxygen atoms driven by Joule heating. This confirmation and quantification of two opposing nanoscale radial forces that affect bipolar memristor switching are important components for any future physics-based compact model for the electronic switching of these devices.
View details for DOI 10.1021/acsnano.6b06275
View details for Web of Science ID 000391079700065
View details for PubMedID 27957851
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Influence of porosity on electrical properties of low-k dielectrics irradiated with vacuum-ultraviolet radiation
APPLIED PHYSICS LETTERS
2016; 109 (12)
View details for DOI 10.1063/1.4962899
View details for Web of Science ID 000384558700047
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The effect of vacuum ultraviolet irradiation on the time-dependent dielectric breakdown of organosilicate dielectrics
APPLIED PHYSICS LETTERS
2016; 109 (12)
View details for DOI 10.1063/1.4962949
View details for Web of Science ID 000384558700050
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High Current Density and Low Thermal Conductivity of Atomically Thin Semimetallic WTe2.
ACS nano
2016; 10 (8): 7507-7514
Abstract
Two-dimensional (2D) semimetals beyond graphene have been relatively unexplored in the atomically thin limit. Here, we introduce a facile growth mechanism for semimetallic WTe2 crystals and then fabricate few-layer test structures while carefully avoiding degradation from exposure to air. Low-field electrical measurements of 80 nm to 2 μm long devices allow us to separate intrinsic and contact resistance, revealing metallic response in the thinnest encapsulated and stable WTe2 devices studied to date (3-20 layers thick). High-field electrical measurements and electrothermal modeling demonstrate that ultrathin WTe2 can carry remarkably high current density (approaching 50 MA/cm(2), higher than most common interconnect metals) despite a very low thermal conductivity (of the order ∼3 Wm(-1) K(-1)). These results suggest several pathways for air-stable technological viability of this layered semimetal.
View details for DOI 10.1021/acsnano.6b02368
View details for PubMedID 27434729
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Effects of ultraviolet (UV) irradiation in air and under vacuum on low-k dielectrics
AIP ADVANCES
2016; 6 (7)
View details for DOI 10.1063/1.4959277
View details for Web of Science ID 000382403600012
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Nonthermal combined ultraviolet and vacuum-ultraviolet curing process for organosilicate dielectrics
APPLIED PHYSICS LETTERS
2016; 108 (24)
View details for DOI 10.1063/1.4954176
View details for Web of Science ID 000379037200055
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First-principles study of carbon impurity effects in the pseudo-hexagonal Ta2O5
CURRENT APPLIED PHYSICS
2016; 16 (6): 638-643
View details for DOI 10.1016/j.cap.2016.03.014
View details for Web of Science ID 000374659600006
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Kinetic Study of Hydrogen Evolution Reaction over Strained MoS2 with Sulfur Vacancies Using Scanning Electrochemical Microscopy
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
2016; 138 (15): 5123-5129
Abstract
Molybdenum disulfide (MoS2), with its active edge sites, is a proposed alternative to platinum for catalyzing the hydrogen evolution reaction (HER). Recently, the inert basal plane of MoS2 was successfully activated and optimized with excellent intrinsic HER activity by creating and further straining sulfur (S) vacancies. Nevertheless, little is known about the HER kinetics of those S vacancies and the additional effects from elastic tensile strain. Herein, scanning electrochemical microscopy was used to determine the HER kinetic data for both unstrained S vacancies (formal potential Ev0 = −0.53 VAg/AgCl, electron-transfer coefficient αv = 0.4, electron-transfer rate constant kv0 = 2.3 × 10(–4) cm/s) and strained S vacancies (Esv0= −0.53 VAg/AgCl, αsv = 0.4, ksv0 = 1.0 × 10(–3) cm/s) on the basal plane of MoS2 monolayers, and the strained S vacancy has an electron-transfer rate 4 times higher than that of the unstrained S vacancy. This study provides a general platform for measuring the kinetics of two-dimensional material-based catalysts.
View details for DOI 10.1021/jacs.6b01377
View details for PubMedID 26997198
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Direct Observation of Localized Radial Oxygen Migration in Functioning Tantalum Oxide Memristors
ADVANCED MATERIALS
2016; 28 (14): 2772-2776
Abstract
Oxygen migration in tantalum oxide, a promising next-generation storage material, is studied using in operando X-ray absorption spectromicroscopy. This approach allows a physical description of the evolution of conduction channel and eventual device failure. The observed ring-like patterns of oxygen concentration are modeled using thermophoretic forces and Fick diffusion, establishing the critical role of temperature-driven oxygen migration.
View details for DOI 10.1002/adma.201505435
View details for Web of Science ID 000373839600013
View details for PubMedID 26833926
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Filament-Induced Anisotropic Oxygen Vacancy Diffusion and Charge Trapping Effects in Hafnium Oxide RRAM
IEEE ELECTRON DEVICE LETTERS
2016; 37 (4): 400-403
View details for DOI 10.1109/LED.2016.2524450
View details for Web of Science ID 000373129300012
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Memristors: Direct Observation of Localized Radial Oxygen Migration in Functioning Tantalum Oxide Memristors (Adv. Mater. 14/2016).
Advanced materials
2016; 28 (14): 2771-?
Abstract
As information bits of 0's and 1's are stored in crosspoint tantalum oxide memristors, or resistive random access memory (RRAM) cells, nanoscale-resolution in operando X-ray transmission spectromicroscopy is used by J. P. Strachan and co-workers, as reported on page 2772, to directly observe oxygen migration and clustering, revealing an important operation and failure mechanism of RRAM, a frontrunner technology for next-generation computer memory.
View details for DOI 10.1002/adma.201670096
View details for PubMedID 27062166
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Increased photoluminescence from single-mode microwave annealing of N-type Ge-on-Si
APPLIED PHYSICS LETTERS
2016; 108 (11)
View details for DOI 10.1063/1.4944578
View details for Web of Science ID 000373058400022
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The effects of uniaxial and biaxial strain on the electronic structure of germanium
COMPUTATIONAL MATERIALS SCIENCE
2016; 112: 263-268
View details for DOI 10.1016/j.commatsci.2015.10.023
View details for Web of Science ID 000366053000033
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Hydrogen doping in HfO2 resistance change random access memory
APPLIED PHYSICS LETTERS
2016; 108 (4)
View details for DOI 10.1063/1.4940369
View details for Web of Science ID 000375217200058
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HfO2-Based RRAM: Electrode Effects, Ti/HfO2 Interface, Charge Injection, and Oxygen (O) Defects Diffusion Through Experiment and Ab Initio Calculations
IEEE TRANSACTIONS ON ELECTRON DEVICES
2016; 63 (1): 360-368
View details for DOI 10.1109/TED.2015.2503145
View details for Web of Science ID 000367259600047
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Significance of the double-layer capacitor effect in polar rubbery dielectrics and exceptionally stable low-voltage high transconductance organic transistors
SCIENTIFIC REPORTS
2015; 5
Abstract
Both high gain and transconductance at low operating voltages are essential for practical applications of organic field-effect transistors (OFETs). Here, we describe the significance of the double-layer capacitance effect in polar rubbery dielectrics, even when present in a very low ion concentration and conductivity. We observed that this effect can greatly enhance the OFET transconductance when driven at low voltages. Specifically, when the polar elastomer poly(vinylidene fluoride-co-hexafluoropropylene) (e-PVDF-HFP) was used as the dielectric layer, despite a thickness of several micrometers, we obtained a transconductance per channel width 30 times higher than that measured for the same organic semiconductors fabricated on a semicrystalline PVDF-HFP with a similar thickness. After a series of detailed experimental investigations, we attribute the above observation to the double-layer capacitance effect, even though the ionic conductivity is as low as 10(-10) S/cm. Different from previously reported OFETs with double-layer capacitance effects, our devices showed unprecedented high bias-stress stability in air and even in water.
View details for DOI 10.1038/srep17849
View details for PubMedID 26658331
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Measurements of Schottky barrier at the low-k SiOC:H/Cu interface using vacuum ultraviolet photoemission spectroscopy
APPLIED PHYSICS LETTERS
2015; 107 (23)
View details for DOI 10.1063/1.4937582
View details for Web of Science ID 000367010800043
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On the Origin of Low-Resistance State Retention Failure in HfO2-Based RRAM and Impact of Doping/Alloying
IEEE TRANSACTIONS ON ELECTRON DEVICES
2015; 62 (12): 4029-4036
View details for DOI 10.1109/TED.2015.2490545
View details for Web of Science ID 000365225700016
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Deep recombination centers in Cu2ZnSnSe4 revealed by screened-exchange hybrid density functional theory
PHYSICAL REVIEW B
2015; 92 (19)
View details for DOI 10.1103/PhysRevB.92.195201
View details for Web of Science ID 000364016300003
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Characterization of electronic structure of periodically strained graphene
APPLIED PHYSICS LETTERS
2015; 107 (18)
View details for DOI 10.1063/1.4934701
View details for Web of Science ID 000364580800063
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Fluorophore-based sensor for oxygen radicals in processing plasmas
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
2015; 33 (6)
View details for DOI 10.1116/1.4930315
View details for Web of Science ID 000365503800022
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3-D Resistive Memory Arrays: From Intrinsic Switching Behaviors to Optimization Guidelines
IEEE TRANSACTIONS ON ELECTRON DEVICES
2015; 62 (10): 3160-3167
View details for DOI 10.1109/TED.2015.2468602
View details for Web of Science ID 000361684000008
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Defect-induced bandgap narrowing in low-k dielectrics
APPLIED PHYSICS LETTERS
2015; 107 (8)
View details for DOI 10.1063/1.4929702
View details for Web of Science ID 000360593900053
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In-operando synchronous time-multiplexed O K-edge x-ray absorption spectromicroscopy of functioning tantalum oxide memristors
JOURNAL OF APPLIED PHYSICS
2015; 118 (3)
View details for DOI 10.1063/1.4926477
View details for Web of Science ID 000358429200026
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Ab initio modeling of oxygen-vacancy formation in doped-HfOx RRAM: Effects of oxide phases, stoichiometry, and dopant concentrations
APPLIED PHYSICS LETTERS
2015; 107 (1)
View details for DOI 10.1063/1.4926337
View details for Web of Science ID 000357824200048
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Amorphorized tantalum-nickel binary films for metal gate applications
APPLIED PHYSICS LETTERS
2015; 106 (15)
View details for DOI 10.1063/1.4918375
View details for Web of Science ID 000353160700016
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H-treatment impact on conductive-filament formation and stability in Ta2O5-based resistive-switching memory cells
JOURNAL OF APPLIED PHYSICS
2015; 117 (12)
View details for DOI 10.1063/1.4915946
View details for Web of Science ID 000352315700035
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Structural and electrical characterization of CoTiN metal gates
JOURNAL OF APPLIED PHYSICS
2015; 117 (7)
View details for DOI 10.1063/1.4908547
View details for Web of Science ID 000351130900036
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Effects of vacuum-ultraviolet irradiation on copper penetration into low-k dielectrics under bias-temperature stress
APPLIED PHYSICS LETTERS
2015; 106 (1)
View details for DOI 10.1063/1.4905462
View details for Web of Science ID 000347976900040
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Sequential Electronic and Structural Transitions in VO2 Observed Using X-ray Absorption Spectromicroscopy
ADVANCED MATERIALS
2014; 26 (44): 7505-7509
Abstract
The popular dual electronic and structural transitions in VO2 are explored using X-ray absorption spectromicroscopy with high spatial and spectral resolutions. It is found that during both heating and cooling, the electronic transition always precedes the structural Peierls transition. Between the two transitions, there are intermediate states that are spectrally isolated here.
View details for DOI 10.1002/adma.201402404
View details for Web of Science ID 000345514600014
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Sequential electronic and structural transitions in VO2 observed using X-ray absorption spectromicroscopy.
Advanced materials
2014; 26 (44): 7505-7509
Abstract
The popular dual electronic and structural transitions in VO2 are explored using X-ray absorption spectromicroscopy with high spatial and spectral resolutions. It is found that during both heating and cooling, the electronic transition always precedes the structural Peierls transition. Between the two transitions, there are intermediate states that are spectrally isolated here.
View details for DOI 10.1002/adma.201402404
View details for PubMedID 25319233
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Effect of vacuum-ultraviolet irradiation on the dielectric constant of low-k organosilicate dielectrics
APPLIED PHYSICS LETTERS
2014; 105 (20)
View details for DOI 10.1063/1.4901742
View details for Web of Science ID 000345513300057
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First-principles study of A-site substitution in ferroelectric bismuth titanate
JOURNAL OF MATERIALS SCIENCE
2014; 49 (18): 6363-6372
View details for DOI 10.1007/s10853-014-8363-4
View details for Web of Science ID 000338348000021
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Time-dependent dielectric breakdown measurements of porous organosilicate glass using mercury and solid metal probes
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
2014; 32 (5)
View details for DOI 10.1116/1.4891563
View details for Web of Science ID 000342208400021
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Surface charge sensing by altering the phase transition in VO2
JOURNAL OF APPLIED PHYSICS
2014; 116 (7)
View details for DOI 10.1063/1.4893577
View details for Web of Science ID 000341189400062
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Effects of ZrO2 doping on HfO2 resistive switching memory characteristics
APPLIED PHYSICS LETTERS
2014; 105 (7)
View details for DOI 10.1063/1.4893568
View details for Web of Science ID 000341189800037
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Effects of plasma and vacuum-ultraviolet exposure on the mechanical properties of low-k porous organosilicate glass
JOURNAL OF APPLIED PHYSICS
2014; 116 (4)
View details for DOI 10.1063/1.4891501
View details for Web of Science ID 000340710700067
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Role of nitrogen incorporation into Al2O3-based resistive random-access memory
APPLIED PHYSICS EXPRESS
2014; 7 (7)
View details for DOI 10.7567/APEX.7.074202
View details for Web of Science ID 000339930100024
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Multi-level control of conductive nano-filament evolution in HfO2 ReRAM by pulse-train operations
NANOSCALE
2014; 6 (11): 5698-5702
Abstract
Precise electrical manipulation of nanoscale defects such as vacancy nano-filaments is highly desired for the multi-level control of ReRAM. In this paper we present a systematic investigation on the pulse-train operation scheme for reliable multi-level control of conductive filament evolution. By applying the pulse-train scheme to a 3 bit per cell HfO2 ReRAM, the relative standard deviations of resistance levels are improved up to 80% compared to the single-pulse scheme. The observed exponential relationship between the saturated resistance and the pulse amplitude provides evidence for the gap-formation model of the filament-rupture process.
View details for DOI 10.1039/c4nr00500g
View details for Web of Science ID 000336883000022
View details for PubMedID 24769626
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Electronic structure and stability of low symmetry Ta2O5 polymorphs
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
2014; 8 (6): 560-565
View details for DOI 10.1002/pssr.201409018
View details for Web of Science ID 000338021200015
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A Combined Ab Initio and Experimental Study on the Nature of Conductive Filaments in Pt/HfO2/Pt Resistive Random Access Memory
IEEE TRANSACTIONS ON ELECTRON DEVICES
2014; 61 (5): 1394-1402
View details for DOI 10.1109/TED.2014.2312943
View details for Web of Science ID 000337753300026
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Effect of water uptake on the fracture behavior of low-k organosilicate glass
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
2014; 32 (3)
View details for Web of Science ID 000335965300027
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Impact of electrode nature on the filament formation and variability in HfO2 RRAM
International Reliability Physics Symposium (IRPS)
IEEE. 2014
View details for Web of Science ID 000343833200090
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Ab initio modeling of resistive switching mechanism in binary metal oxides
IEEE International Symposium on Circuits and Systems (ISCAS)
IEEE. 2014: 2021–2024
View details for Web of Science ID 000346488600507
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Local temperature redistribution and structural transition during joule-heating-driven conductance switching in VO2.
Advanced materials
2013; 25 (42): 6128-6132
Abstract
Joule-heating induced conductance-switching is studied in VO2 , a Mott insulator. Complementary in situ techniques including optical characterization, blackbody microscopy, scanning transmission X-ray microscopy (STXM) and numerical simulations are used. Abrupt redistribution in local temperature is shown to occur upon conductance-switching along with a structural phase transition, at the same current.
View details for DOI 10.1002/adma.201302046
View details for PubMedID 23868142
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Interface trap evaluation of Pd/Al2O3/GaN metal oxide semiconductor capacitors and the influence of near-interface hydrogen
APPLIED PHYSICS LETTERS
2013; 103 (20)
View details for DOI 10.1063/1.4827102
View details for Web of Science ID 000327818700027
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Local Temperature Redistribution and Structural Transition During Joule-Heating-Driven Conductance Switching in VO2
ADVANCED MATERIALS
2013; 25 (42): 6128-6132
Abstract
Joule-heating induced conductance-switching is studied in VO2 , a Mott insulator. Complementary in situ techniques including optical characterization, blackbody microscopy, scanning transmission X-ray microscopy (STXM) and numerical simulations are used. Abrupt redistribution in local temperature is shown to occur upon conductance-switching along with a structural phase transition, at the same current.
View details for DOI 10.1002/adma.201302046
View details for Web of Science ID 000327801900016
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Vacancy Cohesion-Isolation Phase Transition Upon Charge Injection and Removal in Binary Oxide-Based RRAM Filamentary-Type Switching
IEEE TRANSACTIONS ON ELECTRON DEVICES
2013; 60 (10): 3400-3406
View details for DOI 10.1109/TED.2013.2279397
View details for Web of Science ID 000324928900059
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Charge-dependent oxygen vacancy diffusion in Al2O3-based resistive-random-access-memories
APPLIED PHYSICS LETTERS
2013; 103 (9)
View details for DOI 10.1063/1.4819772
View details for Web of Science ID 000323846900064
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Essential role for ligand-dependent feedback antagonism of vertebrate hedgehog signaling by PTCH1, PTCH2 and HHIP1 during neural patterning
DEVELOPMENT
2013; 140 (16): 3423-3434
Abstract
Hedgehog (HH) signaling is essential for vertebrate and invertebrate embryogenesis. In Drosophila, feedback upregulation of the HH receptor Patched (PTC; PTCH in vertebrates), is required to restrict HH signaling during development. By contrast, PTCH1 upregulation is dispensable for early HH-dependent patterning in mice. Unique to vertebrates are two additional HH-binding antagonists that are induced by HH signaling, HHIP1 and the PTCH1 homologue PTCH2. Although HHIP1 functions semi-redundantly with PTCH1 to restrict HH signaling in the developing nervous system, a role for PTCH2 remains unresolved. Data presented here define a novel role for PTCH2 as a ciliary localized HH pathway antagonist. While PTCH2 is dispensable for normal ventral neural patterning, combined removal of PTCH2- and PTCH1-feedback antagonism produces a significant expansion of HH-dependent ventral neural progenitors. Strikingly, complete loss of PTCH2-, HHIP1- and PTCH1-feedback inhibition results in ectopic specification of ventral cell fates throughout the neural tube, reflecting constitutive HH pathway activation. Overall, these data reveal an essential role for ligand-dependent feedback inhibition of vertebrate HH signaling governed collectively by PTCH1, PTCH2 and HHIP1.
View details for DOI 10.1242/dev.095083
View details for Web of Science ID 000322442900013
View details for PubMedID 23900540
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Surface photoconductivity of organosilicate glass dielectrics induced by vacuum-ultraviolet radiation
JOURNAL OF APPLIED PHYSICS
2013; 114 (6)
View details for DOI 10.1063/1.4817427
View details for Web of Science ID 000323177100060
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Amorphous thin film TaWSiC as a diffusion barrier for copper interconnects
APPLIED PHYSICS LETTERS
2013; 103 (2)
View details for DOI 10.1063/1.4813396
View details for Web of Science ID 000321761000036
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First principles modeling of charged oxygen vacancy filaments in reduced TiO2-implications to the operation of non-volatile memory devices
MATHEMATICAL AND COMPUTER MODELLING
2013; 58 (1-2): 275-281
View details for DOI 10.1016/j.mcm.2012.11.009
View details for Web of Science ID 000320601000028
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Grain boundary composition and conduction in HfO2: An ab initio study
APPLIED PHYSICS LETTERS
2013; 102 (20)
View details for DOI 10.1063/1.4807666
View details for Web of Science ID 000320619300040
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p-Channel Field-Effect Transistors Based on C-60 Doped with Molybdenum Trioxide
ACS APPLIED MATERIALS & INTERFACES
2013; 5 (7): 2337-2341
Abstract
Fullerene (C60) is a well-known n-channel organic semiconductor. We demonstrate that p-channel C60 field-effect transistors are possible by doping with molybdenum trioxide (MoO3). The device performance of the p-channel C60 field-effect transistors, such as mobility, threshold voltage, and on/off ratio is varied in a controlled manner by changing doping concentration. This work demonstrates the utility of charge transfer doping to obtain both n- and p-channel field-effect transistors with a single organic semiconductor.
View details for DOI 10.1021/am3026568
View details for Web of Science ID 000317549100007
View details for PubMedID 23446111
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Generalized mechanism of the resistance switching in binary-oxide-based resistive random-access memories
PHYSICAL REVIEW B
2013; 87 (15)
View details for DOI 10.1103/PhysRevB.87.155201
View details for Web of Science ID 000317195000002
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Physical Guiding Principles for High Quality Resistive Random Access Memory Stack with Al2O3 Insertion Layer
JAPANESE JOURNAL OF APPLIED PHYSICS
2013; 52 (4)
View details for DOI 10.7567/JJAP.52.04CD11
View details for Web of Science ID 000320002400059
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Dopant selection rules for desired electronic structure and vacancy formation characteristics of TiO2 resistive memory
APPLIED PHYSICS LETTERS
2013; 102 (8)
View details for DOI 10.1063/1.4794083
View details for Web of Science ID 000315597000081
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Achieving direct band gap in germanium through integration of Sn alloying and external strain
JOURNAL OF APPLIED PHYSICS
2013; 113 (7)
View details for DOI 10.1063/1.4792649
View details for Web of Science ID 000315262800027
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Prediction of Semimetallic Tetragonal Hf2O3 and Zr2O3 from First Principles
PHYSICAL REVIEW LETTERS
2013; 110 (6)
Abstract
Tetragonal semimetallic phases are predicted for Hf(2)O(3) and Zr(2)O(3) using density functional theory. The structures belong to space group P4[over ¯]m2 and are more stable than their corundum counterparts. Many body corrections at first order confirm their semimetallic character. The carrier concentrations are very similar for both materials, and are estimated as 1.8×10(21) cm(-3) for both electrons and holes, allowing for electric conduction. This could serve as a basic explanation for the low resistance state of hafnia-based resistive random access memory.
View details for DOI 10.1103/PhysRevLett.110.065502
View details for Web of Science ID 000314687300023
View details for PubMedID 23432270
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Theoretical Design of Desirable Stack Structure for Resistive Random Access Memories
Symposium on Semiconductors, Dielectrics, and Metals for Nanoelectronics 11 held during the 224th Meeting of the Electrochemical-Society
ELECTROCHEMICAL SOC INC. 2013: 181–88
View details for DOI 10.1149/05807.0181ecst
View details for Web of Science ID 000328065400022
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Investigation of the role of electrodes on the retention performance of HfOx based RRAM cells by experiments, atomistic simulations and device physical modeling
IEEE International Reliability Physics Symposium (IRPS)
IEEE. 2013
View details for Web of Science ID 000325097500101
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Effect of Composition on Structural and Electrical Properties of Amorphous Ta-W-Si-C Metal Thin Films
ECS SOLID STATE LETTERS
2013; 2 (10): P86-P88
View details for DOI 10.1149/2.003310ssl
View details for Web of Science ID 000322995700003
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Design and Optimization Methodology for 3D RRAM Arrays
IEEE International Electron Devices Meeting (IEDM)
IEEE. 2013
View details for Web of Science ID 000346509500156
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Physical Origins of ON-OFF Switching in ReRAM via V-O Based Conducting Channels
31st International Conference on the Physics of Semiconductors (ICPS)
AMER INST PHYSICS. 2013: 11–12
View details for DOI 10.1063/1.4848260
View details for Web of Science ID 000331793000005
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Nanoscale (similar to 10nm) 3D vertical ReRAM and NbO2 threshold selector with TiN electrode
IEEE International Electron Devices Meeting (IEDM)
IEEE. 2013
View details for Web of Science ID 000346509500065
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First-Principles Study of Oxygen Vacancy and Hydrogen Impurity Effects in the Pseudo-hexagonal Ta2O5
2nd Symposium on Nonvolatile Memories held at the 224th Meeting of the Electrochemical-Society
ELECTROCHEMICAL SOC INC. 2013: 41–44
View details for DOI 10.1149/05805.0041ecst
View details for Web of Science ID 000329646100006
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Neural-specific Sox2 input and differential Gli-binding affinity provide context and positional information in Shh-directed neural patterning
GENES & DEVELOPMENT
2012; 26 (24): 2802-2816
Abstract
In the vertebrate neural tube, regional Sonic hedgehog (Shh) signaling invokes a time- and concentration-dependent induction of six different cell populations mediated through Gli transcriptional regulators. Elsewhere in the embryo, Shh/Gli responses invoke different tissue-appropriate regulatory programs. A genome-scale analysis of DNA binding by Gli1 and Sox2, a pan-neural determinant, identified a set of shared regulatory regions associated with key factors central to cell fate determination and neural tube patterning. Functional analysis in transgenic mice validates core enhancers for each of these factors and demonstrates the dual requirement for Gli1 and Sox2 inputs for neural enhancer activity. Furthermore, through an unbiased determination of Gli-binding site preferences and analysis of binding site variants in the developing mammalian CNS, we demonstrate that differential Gli-binding affinity underlies threshold-level activator responses to Shh input. In summary, our results highlight Sox2 input as a context-specific determinant of the neural-specific Shh response and differential Gli-binding site affinity as an important cis-regulatory property critical for interpreting Shh morphogen action in the mammalian neural tube.
View details for DOI 10.1101/gad.207142.112
View details for Web of Science ID 000312775700012
View details for PubMedID 23249739
View details for PubMedCentralID PMC3533082
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Temperature-dependent capacitance-voltage analysis of defects in Al2O3 gate dielectric stacks on GaN
APPLIED PHYSICS LETTERS
2012; 101 (24)
View details for DOI 10.1063/1.4769827
View details for Web of Science ID 000312490000025
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The effects of vacuum ultraviolet radiation on low-k dielectric films
JOURNAL OF APPLIED PHYSICS
2012; 112 (11)
View details for DOI 10.1063/1.4751317
View details for Web of Science ID 000312490700001
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First principles calculations of oxygen vacancy-ordering effects in resistance change memory materials incorporating binary transition metal oxides
JOURNAL OF MATERIALS SCIENCE
2012; 47 (21): 7498-7514
View details for DOI 10.1007/s10853-012-6638-1
View details for Web of Science ID 000307520900013
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Theory and Experiments of the Impact of Work-Function Variability on Threshold Voltage Variability in MOS Devices
IEEE TRANSACTIONS ON ELECTRON DEVICES
2012; 59 (11): 3124-3126
View details for DOI 10.1109/TED.2012.2212021
View details for Web of Science ID 000310385100039
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Tuning the Built-in Electric Field in Ferroelectric Pb(Zr0.2Ti0.8)O-3 Films for Long-Term Stability of Single-Digit Nanometer Inverted Domains
NANO LETTERS
2012; 12 (11): 5455-5463
Abstract
The emergence of new technologies, such as whole genome sequencing systems, which generate a large amount of data, is requiring ultrahigh storage capacities. Due to their compactness and low power consumption, probe-based memory devices using Pb(Zr(0.2)Ti(0.8))O(3) (PZT) ferroelectric films are the ideal candidate for such applications where portability is desired. To achieve ultrahigh (>1 Tbit/in(2)) storage densities, sub-10 nm inverted domains are required. However, such domains remain unstable and can invert back to their original polarization due to the effects of an antiparallel built-in electric field in the PZT film, domain-wall, and depolarization energies. Here, we show that the built-in electric-field can be tuned and suppressed by repetitive hydrogen and oxygen plasma treatments. Such treatments trigger reversible Pb reduction/oxidation activity, which alters the electrochemistry of the Pb overlayer and compensates for charges induced by the Pb vacancies. This tuning mechanism is used to demonstrate the writing of stable and equal size sub-4 nm domains in both up- and down-polarized PZT films, corresponding to eight inverted unit-cells. The bit sizes recorded here are the smallest ever achieved, which correspond to potential 60 Tbit/in(2) data storage densities.
View details for DOI 10.1021/nl302911k
View details for Web of Science ID 000311244400003
View details for PubMedID 23043427
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Hard HfB2 tip-coatings for ultrahigh density probe-based storage
APPLIED PHYSICS LETTERS
2012; 101 (9)
View details for DOI 10.1063/1.4748983
View details for Web of Science ID 000308408100026
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Engineering the metal gate electrode for controlling the threshold voltage of organic transistors
APPLIED PHYSICS LETTERS
2012; 101 (6)
View details for DOI 10.1063/1.4739511
View details for Web of Science ID 000307862400089
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Charging response of back-end-of-the-line barrier dielectrics to VUV radiation
THIN SOLID FILMS
2012; 520 (16): 5300-5303
View details for DOI 10.1016/j.tsf.2012.04.014
View details for Web of Science ID 000305719000035
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Electroluminescence from strained germanium membranes and implications for an efficient Si-compatible laser
APPLIED PHYSICS LETTERS
2012; 100 (13)
View details for DOI 10.1063/1.3699224
View details for Web of Science ID 000302230800012
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Ti-electrode effects of NiO based resistive switching memory with Ni insertion layer
APPLIED PHYSICS LETTERS
2012; 100 (13)
View details for DOI 10.1063/1.3697691
View details for Web of Science ID 000302230800079
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Time-dependent dielectric breakdown of plasma-exposed porous organosilicate glass
APPLIED PHYSICS LETTERS
2012; 100 (11)
View details for DOI 10.1063/1.3693526
View details for Web of Science ID 000302204900059
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ON-OFF switching mechanism of resistive-random-access-memories based on the formation and disruption of oxygen vacancy conducting channels
APPLIED PHYSICS LETTERS
2012; 100 (7)
View details for DOI 10.1063/1.3685222
View details for Web of Science ID 000300436800077
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Towards High Mobility GeSn Channel nMOSFETs: Improved Surface Passivation Using Novel Ozone Oxidation Method
IEEE International Electron Devices Meeting (IEDM)
IEEE. 2012
View details for Web of Science ID 000320615600095
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GeSn Channel n and p MOSFETs
5th SiGe, Ge, and Related Compounds - Materials, Processing and Devices Symposium held at the 220th Meeting of the Electrochemical-Society (ECS)
ELECTROCHEMICAL SOC INC. 2012: 937–41
View details for DOI 10.1149/05009.0937ecst
View details for Web of Science ID 000338015300111
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Computational Study toward Micro Electronics Engineering
28th International Conference on Microelectronics (MIEL)
IEEE. 2012: 65–70
View details for Web of Science ID 000309119600010
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Physics in Designing Desirable ReRAM Stack Structure-Atomistic Recipes Based on Oxygen Chemical Potential Control and Charge Injection/Removal
IEEE International Electron Devices Meeting (IEDM)
IEEE. 2012
View details for Web of Science ID 000320615600121
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The effects of plasma exposure on low-k dielectric materials
Advanced Etch Technology for Nanopatterning Conference (AETNC)/SPIE Advanced Lithography Symposium
SPIE-INT SOC OPTICAL ENGINEERING. 2012
View details for DOI 10.1117/12.917967
View details for Web of Science ID 000304817200011
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Germanium on Insulator (GOI) Structure Using Hetero-Epitaxial Lateral Overgrowth on Silicon
4th International Symposium on Graphene, Ge/III-V and Emerging Materials For Post-CMOS Applications held at the 221st Meeting of the Electrochemical-Society (ECS) as Symposium E2
ELECTROCHEMICAL SOC INC. 2012: 203–8
View details for DOI 10.1149/1.3700469
View details for Web of Science ID 000316890000023
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Plasma and vacuum ultraviolet induced charging of SiO2 and HfO2 patterned structures
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
2012; 30 (1)
View details for DOI 10.1116/1.3654012
View details for Web of Science ID 000298992800009
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Hot forming to improve memory window and uniformity of low-power HfOx-based RRAMs
4th IEEE International Memory Workshop (IMW)
IEEE. 2012
View details for Web of Science ID 000332985300026
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Asymmetry, Vacancy Engineering and Mechanism for Bipolar RRAM
4th IEEE International Memory Workshop (IMW)
IEEE. 2012
View details for Web of Science ID 000332985300028
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Design and Materials Selection for Low Power Laterally Actuating Nanoelectromechanical Relays
IEEE International SOI Conference
IEEE. 2012
View details for Web of Science ID 000315378300051
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First Principles Guiding Principles for the Switching Process in Oxide ReRAM
IEEE 11th International Conference on Solid-State and Integrated Circuit Technology (ICSICT)
IEEE. 2012: 489–492
View details for Web of Science ID 000319824700137
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Highly-Strained Germanium as a Gain Medium for Silicon-Compatible Lasers
Conference on Lasers and Electro-Optics (CLEO)
IEEE. 2012
View details for Web of Science ID 000310362401035
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Strained germanium thin film membrane on silicon substrate for optoelectronics
OPTICS EXPRESS
2011; 19 (27): 25866-25872
Abstract
This work presents a novel method to introduce a sustainable biaxial tensile strain larger than 1% in a thin Ge membrane using a stressor layer integrated on a Si substrate. Raman spectroscopy confirms 1.13% strain and photoluminescence shows a direct band gap reduction of 100meV with enhanced light emission efficiency. Simulation results predict that a combination of 1.1% strain and heavy n(+) doping reduces the required injected carrier density for population inversion by over a factor of 60. We also present the first highly strained Ge photodetector, showing an excellent responsivity well beyond 1.6um.
View details for PubMedID 22274174
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Optimization of the Al2O3/GaSb Interface and a High-Mobility GaSb pMOSFET
IEEE TRANSACTIONS ON ELECTRON DEVICES
2011; 58 (10): 3407-3415
View details for DOI 10.1109/TED.2011.2162732
View details for Web of Science ID 000295100300024
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High n-Type Antimony Dopant Activation in Germanium Using Laser Annealing for n(+)/p Junction Diode
IEEE ELECTRON DEVICE LETTERS
2011; 32 (7): 838-840
View details for DOI 10.1109/LED.2011.2142410
View details for Web of Science ID 000292165200002
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InxGa1-xSb channel p-metal-oxide-semiconductor field effect transistors: Effect of strain and heterostructure design
JOURNAL OF APPLIED PHYSICS
2011; 110 (1)
View details for DOI 10.1063/1.3600220
View details for Web of Science ID 000292776500124
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Resistive switching mechanisms in random access memory devices incorporating transition metal oxides: TiO2, NiO and Pr0.7Ca0.3MnO3
NANOTECHNOLOGY
2011; 22 (25)
Abstract
Resistance change random access memory (RRAM) cells, typically built as MIM capacitor structures, consist of insulating layers I sandwiched between metal layers M, where the insulator performs the resistance switching operation. These devices can be electrically switched between two or more stable resistance states at a speed of nanoseconds, with long retention times, high switching endurance, low read voltage, and large switching windows. They are attractive candidates for next-generation non-volatile memory, particularly as a flash successor, as the material properties can be scaled to the nanometer regime. Several resistance switching models have been suggested so far for transition metal oxide based devices, such as charge trapping, conductive filament formation, Schottky barrier modulation, and electrochemical migration of point defects. The underlying fundamental principles of the switching mechanism still lack a detailed understanding, i.e. how to control and modulate the electrical characteristics of devices incorporating defects and impurities, such as oxygen vacancies, metal interstitials, hydrogen, and other metallic atoms acting as dopants. In this paper, state of the art ab initio theoretical methods are employed to understand the effects that filamentary types of stable oxygen vacancy configurations in TiO(2) and NiO have on the electronic conduction. It is shown that strong electronic interactions between metal ions adjacent to oxygen vacancy sites results in the formation of a conductive path and thus can explain the 'ON' site conduction in these materials. Implication of hydrogen doping on electroforming is discussed for Pr(0.7)Ca(0.3)MnO(3) devices based on electrical characterization and FTIR measurements.
View details for DOI 10.1088/0957-4484/22/25/254029
View details for Web of Science ID 000290619900030
View details for PubMedID 21572196
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The nature of the defects generated from plasma exposure in pristine and ultraviolet-cured low-k organosilicate glass
APPLIED PHYSICS LETTERS
2011; 98 (25)
View details for DOI 10.1063/1.3601922
View details for Web of Science ID 000292039900048
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Effect of the dielectric-substrate interface on charge accumulation from vacuum ultraviolet irradiation of low-k porous organosilicate dielectrics
THIN SOLID FILMS
2011; 519 (16): 5464-5466
View details for DOI 10.1016/j.tsf.2011.03.010
View details for Web of Science ID 000292573500027
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Cavity-enhanced direct band electroluminescence near 1550 nm from germanium microdisk resonator diode on silicon
APPLIED PHYSICS LETTERS
2011; 98 (21)
View details for DOI 10.1063/1.3592837
View details for Web of Science ID 000291041600001
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Effects of vacuum ultraviolet radiation on deposited and ultraviolet-cured low-k porous organosilicate glass
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
2011; 29 (3)
View details for DOI 10.1116/1.3570818
View details for Web of Science ID 000289689000002
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Electrical Characteristics of Germanium n(+)/p Junctions Obtained Using Rapid Thermal Annealing of Coimplanted P and Sb
IEEE ELECTRON DEVICE LETTERS
2011; 32 (5): 608-610
View details for DOI 10.1109/LED.2011.2119460
View details for Web of Science ID 000289908500010
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Dielectric relaxation study of hydrogen exposure as a source of two-level systems in Al2O3
JOURNAL OF NON-CRYSTALLINE SOLIDS
2011; 357 (10): 2148-2151
View details for DOI 10.1016/j.jnoncrysol.2011.02.054
View details for Web of Science ID 000291172500022
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Novel Germanium n-MOSFETs With Raised Source/Drain on Selectively Grown Ge on Si for Monolithic Integration
IEEE ELECTRON DEVICE LETTERS
2011; 32 (4): 446-448
View details for DOI 10.1109/LED.2011.2106756
View details for Web of Science ID 000288664800006
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Defects in low-k organosilicate glass and their response to processing as measured with electron-spin resonance
APPLIED PHYSICS LETTERS
2011; 98 (10)
View details for DOI 10.1063/1.3562307
View details for Web of Science ID 000288277200057
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Controlling Electric Dipoles in Nanodielectrics and Its Applications for Enabling Air-Stable n-Channel Organic Transistors
NANO LETTERS
2011; 11 (3): 1161-1165
Abstract
We present a new method to manipulate the channel charge density of field-effect transistors using dipole-generating self-assembled monolayers (SAMs) with different anchor groups. Our approach maintains an ideal interface between the dipole layers and the semiconductor while changing the built-in electric potential by 0.41-0.50 V. This potential difference can be used to change effectively the electrical properties of nanoelectronic devices. We further demonstrate the application of the SAM dipoles to enable air-stable operation of n-channel organic transistors.
View details for DOI 10.1021/nl104087u
View details for Web of Science ID 000288061500043
View details for PubMedID 21323381
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Challenges and opportunities for future non-volatile memory technology
CURRENT APPLIED PHYSICS
2011; 11 (2): E101-E103
View details for DOI 10.1016/j.cap.2011.01.022
View details for Web of Science ID 000294208600023
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Impact of Oxygen Vacancy Ordering on the Formation of a Conductive Filament in TiO2 for Resistive Switching Memory
IEEE ELECTRON DEVICE LETTERS
2011; 32 (2): 197-199
View details for DOI 10.1109/LED.2010.2091489
View details for Web of Science ID 000286677700029
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On the High-Field Transport and Uniaxial Stress Effect in Ge PFETs
IEEE TRANSACTIONS ON ELECTRON DEVICES
2011; 58 (2): 384-391
View details for DOI 10.1109/TED.2010.2093530
View details for Web of Science ID 000286515400014
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GeSn Technology: Extending the Ge Electronics Roadmap
IEEE International Electron Devices Meeting (IEDM)
IEEE. 2011
View details for Web of Science ID 000300015300100
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High Endurance Performance of 1T1R HfO(x)based RRAM at Low (< 20uA) Operative Current and Elevated (150 degrees C) Temperature
IEEE International Integrated Reliability Workshop Final Report (IIRW)
IEEE. 2011: 146–150
View details for Web of Science ID 000300607100037
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Direct band Ge photoluminescence at 1.6 mu m coupled to Ge-on-Si microdisk resonators
Conference on Lasers and Electro-Optics (CLEO)
IEEE. 2011
View details for Web of Science ID 000295612401163
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Effect of vacuum ultraviolet and ultraviolet irradiation on mobile charges in the bandgap of low-k-porous organosilicate dielectrics
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
2011; 29 (1)
View details for DOI 10.1116/1.3520433
View details for Web of Science ID 000286648300001
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Changes to Charge and Defects in Dielectrics from Ion and Photon Fluences during Plasma Exposure
ELECTROCHEMICAL AND SOLID STATE LETTERS
2011; 14 (3): H107-H109
View details for DOI 10.1149/1.3524403
View details for Web of Science ID 000285974100011
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Role of Hydrogen Ions in TiO2-Based Memory Devices
INTEGRATED FERROELECTRICS
2011; 124: 112-118
View details for DOI 10.1080/10584587.2011.573733
View details for Web of Science ID 000297007500016
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Quasi Passive Optical Switch Based on Transition Metal Oxide Device
Conference on Lasers and Electro-Optics (CLEO)
IEEE. 2011
View details for Web of Science ID 000295612402130
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Damage to low-k porous organosilicate glass from vacuum-ultraviolet irradiation
Conference on Damage to VUV, EUV, and X-ray Optics III
SPIE-INT SOC OPTICAL ENGINEERING. 2011
View details for DOI 10.1117/12.887691
View details for Web of Science ID 000293212000018
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Understanding the Switching Mechanism in RRAM Devices and the Dielectric Breakdown of Ultrathin High-k Gate Stacks from First Principles Calculations
3rd International Conference on Semiconductor Technology for Ultra Large Scale Integrated Circuits and Thin Film Transistors (ULSIC vs TFT)
ELECTROCHEMICAL SOC INC. 2011: 167–78
View details for DOI 10.1149/1.3600737
View details for Web of Science ID 000305898900019
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Reduction in reset current of unipolar NiO-based resistive switching through nickel interfacial layer
APPLIED PHYSICS LETTERS
2010; 97 (25)
View details for DOI 10.1063/1.3528211
View details for Web of Science ID 000285764300040
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Direct band Ge photoluminescence near 1.6 mu m coupled to Ge-on-Si microdisk resonators
APPLIED PHYSICS LETTERS
2010; 97 (24)
View details for DOI 10.1063/1.3526732
View details for Web of Science ID 000285481000002
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Development and characterization of high temperature stable Ta-W-Si-C amorphous metal gates
APPLIED PHYSICS LETTERS
2010; 97 (22)
View details for DOI 10.1063/1.3508952
View details for Web of Science ID 000284965000087
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Reflectance and substrate currents of dielectric layers under vacuum ultraviolet irradiation
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
2010; 28 (6): 1316-1318
View details for DOI 10.1116/1.3488594
View details for Web of Science ID 000283745300008
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Plasma damage effects on low-k porous organosilicate glass
JOURNAL OF APPLIED PHYSICS
2010; 108 (9)
View details for DOI 10.1063/1.3506523
View details for Web of Science ID 000284270900111
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An Ultraclean Tip-Wear Reduction Scheme for Ultrahigh Density Scanning Probe-Based Data Storage
ACS NANO
2010; 4 (10): 5713-5720
Abstract
Probe-based memory devices using ferroelectric media have the potential to achieve ultrahigh data-storage densities under high write-read speeds. However, the high-speed scanning operations over a device lifetime of 5-10 years, which corresponds to a probe tip sliding distance of 5-10 km, can cause the probe tip to mechanically wear, critically affecting its write-read resolution. Here, we show that the long distance tip-wear endurance issue can be resolved by introducing a thin water layer at the tip-media interface-thin enough to form a liquid crystal. By modulating the force at the tip-surface contact, this water crystal layer can act as a viscoelastic material which reduces the stress level on atomic bonds taking part in the wear process. Under our optimized environment, a platinum-iridium probe tip can retain its write-read resolution over 5 km of sliding at a 5 mm/s velocity on a smooth ferroelectric film. We also demonstrate a 3.6 Tbit/inch(2) storage density over a 1 × 1 μm(2) area, which is the highest density ever written on ferroelectric films over such a large area.
View details for DOI 10.1021/nn1013512
View details for Web of Science ID 000283453700032
View details for PubMedID 20929239
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Electronic correlation effects in reduced rutile TiO2 within the LDA+U method
PHYSICAL REVIEW B
2010; 82 (11)
View details for DOI 10.1103/PhysRevB.82.115109
View details for Web of Science ID 000281658400003
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Bilayer metal gate electrodes with tunable work function: Adhesion and interface characterization
JOURNAL OF APPLIED PHYSICS
2010; 108 (5)
View details for DOI 10.1063/1.3466957
View details for Web of Science ID 000282478900037
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Surface potential due to charge accumulation during vacuum ultraviolet exposure for high-k and low-k dielectrics
APPLIED PHYSICS LETTERS
2010; 97 (7)
View details for DOI 10.1063/1.3481079
View details for Web of Science ID 000281153600060
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High quality single-crystal germanium-on-insulator on bulk Si substrates based on multistep lateral over-growth with hydrogen annealing
APPLIED PHYSICS LETTERS
2010; 97 (6)
View details for DOI 10.1063/1.3478242
View details for Web of Science ID 000280940900089
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Contact engineering for organic semiconductor devices via Fermi level depinning at the metal-organic interface
PHYSICAL REVIEW B
2010; 82 (3)
View details for DOI 10.1103/PhysRevB.82.035311
View details for Web of Science ID 000280123900004
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Photoluminescence from silicon dioxide photonic crystal cavities with embedded silicon nanocrystals
PHYSICAL REVIEW B
2010; 81 (23)
View details for DOI 10.1103/PhysRevB.81.235317
View details for Web of Science ID 000278724600001
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Model of metallic filament formation and rupture in NiO for unipolar switching
PHYSICAL REVIEW B
2010; 81 (19)
View details for DOI 10.1103/PhysRevB.81.193202
View details for Web of Science ID 000278142000006
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Effects of vacuum ultraviolet and ultraviolet irradiation on ultrathin hafnium-oxide dielectric layers on (100)Si as measured with electron-spin resonance
APPLIED PHYSICS LETTERS
2010; 96 (19)
View details for DOI 10.1063/1.3430570
View details for Web of Science ID 000277756400053
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Synthesis of TiO2 nanoframe and the prototype of a nanoframe solar cell
NANOTECHNOLOGY
2010; 21 (18)
Abstract
Nanoframes containing 20 nm diameter TiO(2) nanowire arrays were synthesized with polymer templates via cathodic sol-gel deposition followed by 450 degrees C sintering. Raman spectra indicated that they are composed of pure anatase TiO(2). The nanowire array inside the nanoframe was confirmed to be single crystalline by high resolution TEM. Dye-sensitized solar cells based on this nanoframe were fabricated and the effects of the top cover in the nanoframe, which is the only difference between nanoframe cells and nanowire cells, were investigated. The results show that the top cover does not prevent the I( - ) and I(3)( - ) ions underneath from diffusing freely in the electrolyte and causes no deterioration of the cell performance. The nanoframe cell is a promising device in which nanowire arrays are strengthened and the effective internal surface area has the potentiality to be increased without sacrificing the advantages of nanowire cells compared to nanoparticle cells.
View details for DOI 10.1088/0957-4484/21/18/185303
View details for Web of Science ID 000276672100009
View details for PubMedID 20378944
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Uniaxial Stress Engineering for High-Performance Ge NMOSFETs
IEEE TRANSACTIONS ON ELECTRON DEVICES
2010; 57 (5): 1037-1046
View details for DOI 10.1109/TED.2010.2042767
View details for Web of Science ID 000278066500011
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The effects of wet surface clean and in situ interlayer on In-0.52Al0.48As metal-oxide-semiconductor characteristics
APPLIED PHYSICS LETTERS
2010; 96 (14)
View details for DOI 10.1063/1.3379024
View details for Web of Science ID 000276554600066
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Numerical simulation of vacuum-ultraviolet irradiation of dielectric layers
APPLIED PHYSICS LETTERS
2010; 96 (14)
View details for DOI 10.1063/1.3386531
View details for Web of Science ID 000276554600063
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Effects of postgate dielectric treatment on germanium-based metal-oxide-semiconductor device by supercritical fluid technology
APPLIED PHYSICS LETTERS
2010; 96 (11)
Abstract
Supercritical fluid (SCF) technology is employed at low temperature as a postgate dielectric treatment to improve gate SiO(2)germanium (Ge) interface in a Ge-based metal-oxide-semiconductor (Ge-MOS) device. The SCF can transport the oxidant and penetrate the gate oxide layer for the oxidation of SiO(2)Ge interface at 150 degrees C. A smooth interfacial GeO(2) layer between gate SiO(2) and Ge is thereby formed after SCF treatment, and the frequency dispersion of capacitance-voltage characteristics is also effectively alleviated. Furthermore, the electrical degradation of Ge-MOS after a postgate dielectric annealing at 450 degrees C can be restored to a extent similar to the initial state.
View details for DOI 10.1063/1.3365177
View details for Web of Science ID 000275825200042
View details for PubMedCentralID PMC2852447
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Bilayer metal gate electrodes with tunable work function: Mechanism and proposed model
JOURNAL OF APPLIED PHYSICS
2010; 107 (6)
View details for DOI 10.1063/1.3326237
View details for Web of Science ID 000276210800055
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Effect of vacuum ultraviolet and ultraviolet Irradiation on capacitance-voltage characteristics of low-k-porous organosilicate dielectrics
APPLIED PHYSICS LETTERS
2010; 96 (5)
View details for DOI 10.1063/1.3306729
View details for Web of Science ID 000274319500075
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Fully inverted single-digit nanometer domains in ferroelectric films
APPLIED PHYSICS LETTERS
2010; 96 (2)
View details for DOI 10.1063/1.3280371
View details for Web of Science ID 000273689400050
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High Performance Germanium N-MOSFET with Antimony Dopant Activation Beyond 1x10(20) cm(-3)
International Electron Devices Meeting (IEDM)
IEEE. 2010
View details for Web of Science ID 000287997300060
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Development of high-k dielectric for Antimonides and a sub 350 degrees C III-V pMOSFET outperforming Germanium
International Electron Devices Meeting (IEDM)
IEEE. 2010
View details for Web of Science ID 000287997300033
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Characterizations of direct band gap photoluminescence and electroluminescence from epi-Ge on Si
4th SiGe, Ge, and Related Compounds - Materials, Processing and Devices Symposium held at the 218th Meeting of the Electrochemical-Society (ECS)
ELECTROCHEMICAL SOC INC. 2010: 545–54
View details for DOI 10.1149/1.3487585
View details for Web of Science ID 000314957600056
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Effect of isochronal hydrogen annealing on surface roughness and threading dislocation density of epitaxial Ge films grown on Si
6th International Conference on Silicon Epitaxy and Heterostructures (ICSI-6)
ELSEVIER SCIENCE SA. 2010: S136–S139
View details for DOI 10.1016/j.tsf.2009.10.072
View details for Web of Science ID 000274812400030
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Low Temperature Germanium Growth on Silicon Oxide Using Boron Seed Layer and In Situ Dopant Activation
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
2010; 157 (3): H371-H376
View details for DOI 10.1149/1.3295703
View details for Web of Science ID 000274321900093
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Charge Trapping within UV and Vacuum UV Irradiated Low-k Porous Organosilicate Dielectrics
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
2010; 157 (8): G177-G182
View details for DOI 10.1149/1.3435285
View details for Web of Science ID 000279673400052
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Photonic Crystal and Plasmonic Silicon-Based Light Sources
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2010; 16 (1): 132-140
View details for DOI 10.1109/JSTQE.2009.2030777
View details for Web of Science ID 000274382900016
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Understanding of switching phenomena in unipolar NiO-based RRAM
Globecom Workshops
IEEE. 2010: 1886–1889
View details for Web of Science ID 000291611300357
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Quasi-Passive and Reconfigurable Node for Optical Access Network
Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS)
IEEE. 2010
View details for Web of Science ID 000290513601076
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Experimental Demonstration of High Source Velocity and Its Enhancement by Uniaxial Stress in Ge PFETs
Symposium on VLSI Technology (VLSIT)
IEEE. 2010: 215–216
View details for Web of Science ID 000287495500082
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Radical oxidation of germanium for interface gate dielectric GeO2 formation in metal-insulator-semiconductor gate stack
JOURNAL OF APPLIED PHYSICS
2009; 106 (10)
View details for DOI 10.1063/1.3259407
View details for Web of Science ID 000272932300103
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Effect of uniaxial-strain on Ge p-i-n photodiodes integrated on Si
APPLIED PHYSICS LETTERS
2009; 95 (16)
View details for DOI 10.1063/1.3254181
View details for Web of Science ID 000271218200006
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Germanium In Situ Doped Epitaxial Growth on Si for High-Performance n(+)/p-Junction Diode
IEEE ELECTRON DEVICE LETTERS
2009; 30 (9): 1002-1004
View details for DOI 10.1109/LED.2009.2027823
View details for Web of Science ID 000269443000037
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Image Charge and Dipole Combination Model for the Schottky Barrier Tuning at the Dopant Segregated Metal/Semiconductor Interface
IEEE ELECTRON DEVICE LETTERS
2009; 30 (9): 963-965
View details for DOI 10.1109/LED.2009.2025785
View details for Web of Science ID 000269443000024
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The Effect of Oxygen on the Work Function of Tungsten Gate Electrodes in MOS Devices
IEEE ELECTRON DEVICE LETTERS
2009; 30 (9): 925-927
View details for DOI 10.1109/LED.2009.2026717
View details for Web of Science ID 000269443000011
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Atomic Layer Deposition of Dielectrics on Ge and III-V Materials for Ultrahigh Performance Transistors
MRS BULLETIN
2009; 34 (7): 493-503
View details for Web of Science ID 000268159400015
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Room temperature 1.6 microm electroluminescence from Ge light emitting diode on Si substrate.
Optics express
2009; 17 (12): 10019-10024
Abstract
We report the room temperature electroluminescence (EL) at 1.6 microm of a Ge n+/p light emitting diode on a Si substrate. Unlike normal electrically pumped devices, this device shows a super linear luminescence enhancement at high current. By comparing different n type doping concentrations, we observe that a higher concentration is required to achieve better efficiency of the device. Thermal enhancement effects observed in temperature dependent EL spectra show the capability of this device to operate at room temperature or above. These detailed studies show that Ge can be a good candidate for a Si compatible light emitting device.
View details for PubMedID 19506652
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Solution-processed flexible organic transistors showing very-low subthreshold slope with a bilayer polymeric dielectric on plastic
APPLIED PHYSICS LETTERS
2009; 94 (20)
View details for DOI 10.1063/1.3133902
View details for Web of Science ID 000266342800065
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Surface Science of Catalyst Dynamics for Aligned Carbon Nanotube Synthesis on a Full-Scale Quartz Wafer
JOURNAL OF PHYSICAL CHEMISTRY C
2009; 113 (19): 8002-8008
View details for DOI 10.1021/jp810794y
View details for Web of Science ID 000265895500005
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Effect of thermal annealing on charge exchange between oxygen interstitial defects within HfO2 and oxygen-deficient silicon centers within the SiO2/Si interface
APPLIED PHYSICS LETTERS
2009; 94 (16)
View details for DOI 10.1063/1.3122925
View details for Web of Science ID 000265823300054
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Modeling the spatio-temporal network that drives patterning in the vertebrate central nervous system
BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS
2009; 1789 (4): 299-305
Abstract
In this review, we discuss the gene regulatory network underlying the patterning of the ventral neural tube during vertebrate embryogenesis. The neural tube is partitioned into domains of distinct cell fates by inductive signals along both anterior-posterior and dorsal-ventral axes. A defining feature of the dorsal-ventral patterning is the graded distribution of Sonic hedgehog (Shh), which acts as a morphogen to specify several classes of ventral neurons in a concentration-dependent fashion. These inductive signals translate into patterned expressions of transcription factors that define different neural progenitor subtypes. Progenitor boundaries are sharpened by repressive interactions between these transcription factors. The progenitor-expressed transcription factors induce another set of transcription factors that are thought to contribute to neural identities in post-mitotic neural precursors. Thus, the gene regulatory network of the ventral neural tube patterning is characterized by hierarchical expression [inductive signal-->progenitor specifying factors (mitotic)--> precursor specifying factors (post mitotic)--> differentiated neural markers] and cross-repression between progenitor-expressed regulatory factors. Although a number of transcriptional regulators have been identified at each hierarchical level, their precise regulatory relationships are not clear. Here we discuss approaches aimed at clarifying and extending our understanding of the formation and propagation of this network.
View details for DOI 10.1016/j.bbagrm.2009.01.002
View details for Web of Science ID 000265729800008
View details for PubMedID 19445894
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Fermi Level Unpinning and Schottky Barrier Modification by Ti, Sc and V Incorporation at NiSi2/Si Interface
CHINESE PHYSICS LETTERS
2009; 26 (3)
View details for Web of Science ID 000263601300066
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Experimental Study and Statistical Analysis of Solution-Shearing Processed Organic Transistors Based on an Asymmetric Small-Molecule Semiconductor
IEEE TRANSACTIONS ON ELECTRON DEVICES
2009; 56 (2): 176-185
View details for DOI 10.1109/TED.2008.2010580
View details for Web of Science ID 000262816800004
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Fermi level depinning in metal/Ge Schottky junction for metal source/drain Ge metal-oxide-semiconductor field-effect-transistor application
JOURNAL OF APPLIED PHYSICS
2009; 105 (2)
View details for DOI 10.1063/1.3065990
View details for Web of Science ID 000262970900048
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Plasmonic enhancement of emission from Si-nanocrystals
APPLIED PHYSICS LETTERS
2009; 94 (1)
View details for DOI 10.1063/1.3055602
View details for Web of Science ID 000262357800073
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Effect of uniaxial-strain on Ge p-i-n photodiodes integrated on Si
22nd Annual Meeting of the IEEE-Photonics-Society
IEEE. 2009: 369–370
View details for Web of Science ID 000279577600191
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Lattice and electronic effects in rutile TiO2 containing charged oxygen defects from ab initio calculations
Symposium on Materials and Physics for Nonvolatile Memories held at the 2009 MRS Spring Meeting
MATERIALS RESEARCH SOCIETY. 2009: 129–134
View details for Web of Science ID 000274017200016
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Impact of hydrogen on the electroforming of Pr0.7Ca0.3MnO3 resistance-change memory devices
10th Annual Non-Volatile Memory Technology Symposium
IEEE. 2009: 48–51
View details for Web of Science ID 000278758600007
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High Performance n-MOSFETs with Novel Source/Drain on Selectively Grown Ge on Si for Monolithic Integration
IEEE International Electron Devices Meeting (IEDM 2009)
IEEE. 2009: 641–644
View details for Web of Science ID 000279343900166
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High Quality GeO2/Ge Interface Formed by SPA Radical Oxidation and Uniaxial Stress Engineering for High Performance Ge NMOSFETs
Symposium on VLSI Technology
JAPAN SOCIETY APPLIED PHYSICS. 2009: 76–77
View details for Web of Science ID 000275651200027
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Plasmonic Metal-Insulator-Metal Structures for Interaction with Silicon Nanocrystals
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2009)
IEEE. 2009: 1818–1819
View details for Web of Science ID 000274751301234
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Ab initio study of Al-Ni bilayers on SiO2: Implications to effective work function modulation in gate stacks
JOURNAL OF APPLIED PHYSICS
2009; 105 (1)
View details for DOI 10.1063/1.3033368
View details for Web of Science ID 000262534100088
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Carbon Nanotube Quantum Capacitance for Nonlinear Terahertz Circuits
IEEE TRANSACTIONS ON NANOTECHNOLOGY
2009; 8 (1): 31-36
View details for DOI 10.1109/TNANO.2008.2005185
View details for Web of Science ID 000262861500006
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Physical Model of the Impact of Metal Grain Work Function Variability on Emerging Dual Metal Gate MOSFETs and its Implication for SRAM Reliability
IEEE International Electron Devices Meeting (IEDM 2009)
IEEE. 2009: 51–54
View details for Web of Science ID 000279343900012
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Analytical ballistic theory of carbon nanotube transistors: Experimental validation, device physics, parameter extraction, and performance projection
JOURNAL OF APPLIED PHYSICS
2008; 104 (12)
View details for DOI 10.1063/1.3050345
View details for Web of Science ID 000262225100123
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Arsenic-dominated chemistry in the acid cleaning of InGaAs and InAlAs surfaces
APPLIED PHYSICS LETTERS
2008; 93 (19)
View details for DOI 10.1063/1.3025852
View details for Web of Science ID 000260944100134
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Synchrotron radiation photoemission spectroscopic study of band offsets and interface self-cleaning by atomic layer deposited HfO2 on In0.53Ga0.47As and In0.52Al0.48As
APPLIED PHYSICS LETTERS
2008; 93 (18)
View details for DOI 10.1063/1.3020298
View details for Web of Science ID 000260778100030
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Integrating phase-change memory cell with Ge nanowire diode for crosspoint memory-experimental demonstration and analysis
25th IEEE VLSI Test Symposium
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. 2008: 2307–13
View details for DOI 10.1109/TED.2008.927631
View details for Web of Science ID 000258914000003
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Ab initio modeling of Schottky-barrier height tuning by yttrium at nickel silicide/silicon interface
IEEE ELECTRON DEVICE LETTERS
2008; 29 (7): 746-749
View details for DOI 10.1109/LED.2008.2000647
View details for Web of Science ID 000257626000029
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Analysis of electrically biased paramagnetic defect centers in HfO2 and HfxSi1-xO2/(100)Si interfaces
JOURNAL OF APPLIED PHYSICS
2008; 104 (1)
View details for DOI 10.1063/1.2948922
View details for Web of Science ID 000257766500104
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High-performance gate-all-around GeOI p-MOSFETs fabricated by rapid melt growth using plasma nitridation and ALD Al2O3 gate dielectric and self-aligned NiGe contacts
IEEE ELECTRON DEVICE LETTERS
2008; 29 (7): 805-807
View details for DOI 10.1109/LED.2008.2000613
View details for Web of Science ID 000257626000047
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Electronic structures of Nb-W bulk and surface from first principles calculation
JOURNAL OF APPLIED PHYSICS
2008; 103 (4)
View details for DOI 10.1063/1.2844467
View details for Web of Science ID 000254191300024
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HfO2 gate dielectric on (NH4)(2)S passivated (100) GaAs grown by atomic layer deposition
JOURNAL OF APPLIED PHYSICS
2008; 103 (3)
View details for DOI 10.1063/1.2838471
View details for Web of Science ID 000253238100054
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First-principles study of resistance switching in rutile TiO2 with oxygen vacancy
9th Annual Non-Volatile Memory Technology Symposium
IEEE. 2008: 49–53
View details for Web of Science ID 000266157200011
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Ultra-high bandwidth memory with 3D-stacked emerging memory cells
IEEE International Conference on Integrated Circuit Design and Technology
IEEE. 2008: 203–206
View details for Web of Science ID 000258326600049
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Challenge of Nanoelectronic Materials and Devices toward New Nonvolatile Memories
9th International Conference on Solid-State and Integrated-Circuit Technology
IEEE. 2008: 892–896
View details for Web of Science ID 000265971001069
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Fermi-level depinning in metal/Ge Schottky junction and its application to metal source/drainage NMOSFET
Symposium on VLSI Technology
IEEE. 2008: 54–55
View details for Web of Science ID 000259116200020
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Fermi-level depinning in metal/Ge Schottky junction and its application to metal source/drain GeNMOSFET
Symposium on VLSI Technology
IEEE. 2008: 43–44
View details for Web of Science ID 000259442500020
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Passivation studies of germanium surfaces
8th International Symposium on Ultra Clean Processing of Semiconductor Surfaces (UCPSS)
TRANS TECH PUBLICATIONS LTD. 2008: 33–36
View details for Web of Science ID 000253389300008
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An analytical derivation of the density of states, effective mass, and carrier density for achiral carbon nanotubes
IEEE TRANSACTIONS ON ELECTRON DEVICES
2008; 55 (1): 289-297
View details for DOI 10.1109/TED.2007.911078
View details for Web of Science ID 000252059000027
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Effects of strain and interface on work function of a Nb-W metal gate system
APPLIED PHYSICS LETTERS
2007; 91 (24)
View details for DOI 10.1063/1.2821225
View details for Web of Science ID 000251678700037
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Field-programmable rectification in rutile TiO2 crystals
APPLIED PHYSICS LETTERS
2007; 91 (11)
View details for DOI 10.1063/1.2769961
View details for Web of Science ID 000249474000038
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Impact of a process variation on nanowire and nanotube device performance
IEEE TRANSACTIONS ON ELECTRON DEVICES
2007; 54 (9): 2369-2376
View details for DOI 10.1109/TED.2007.901882
View details for Web of Science ID 000249104900030
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High performance, uniaxially-strained, silicon and germanium, double-gate p-MOSFETs
15th Biennial Conference on Insulating Films on Semiconductors
ELSEVIER SCIENCE BV. 2007: 2063–66
View details for DOI 10.1016/j.mee.2007.04.085
View details for Web of Science ID 000247378600052
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High-indium-content InGaAs metal-oxide-semiconductor capacitor with amorphous LaAlO3 gate dielectric
APPLIED PHYSICS LETTERS
2007; 91 (9)
View details for DOI 10.1063/1.2776846
View details for Web of Science ID 000249156100134
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Electro-thermally coupled power optimization for future transistors and its applications
IEEE TRANSACTIONS ON ELECTRON DEVICES
2007; 54 (7): 1696-1704
View details for DOI 10.1109/TED.2007.898242
View details for Web of Science ID 000247643800015
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An analytical compact circuit model for nanowire FET
IEEE TRANSACTIONS ON ELECTRON DEVICES
2007; 54 (7): 1637-1644
View details for DOI 10.1109/TED.2007.899397
View details for Web of Science ID 000247643800007
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Measuring the capacitance of individual semiconductor nanowires for carrier mobility assessment
NANO LETTERS
2007; 7 (6): 1561-1565
Abstract
Capacitance-voltage characteristics of individual germanium nanowire field effect transistors were directly measured and used to assess carrier mobility in nanowires for the first time, thereby removing uncertainties in calculated mobility due to device geometries, surface and interface states, and gate dielectric constants and thicknesses. Direct experimental evidence showed that surround-gated nanowire transistors exhibit higher capacitance and better electrostatic gate control than top-gated devices, and are the most promising structure for future high performance nanoelectronics.
View details for DOI 10.1021/nl070378w
View details for Web of Science ID 000247186800023
View details for PubMedID 17488051
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Power optimization for SRAM and its scaling
IEEE TRANSACTIONS ON ELECTRON DEVICES
2007; 54 (4): 715-722
View details for DOI 10.1109/TED.2007.891869
View details for Web of Science ID 000245327900014
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Bipolar resistive switching in polycrystalline TiO2 films
APPLIED PHYSICS LETTERS
2007; 90 (11)
View details for DOI 10.1063/1.2712777
View details for Web of Science ID 000244959200094
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Resistive switching mechanism in ZnxCd1-xS nonvolatile memory devices
IEEE ELECTRON DEVICE LETTERS
2007; 28 (1): 14-16
View details for DOI 10.1109/LED.2006.887640
View details for Web of Science ID 000243280900006
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Analytical model of carbon nanotube electrostatics: Density of states, effective mass, carrier density, and quantum capacitance
IEEE International Electron Devices Meeting
IEEE. 2007: 753–756
View details for Web of Science ID 000259347800172
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Photoluminescence decay dynamics of silicon-rich silicon nitride film in photonic crystal nanocavity
20th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society
IEEE. 2007: 329–330
View details for Web of Science ID 000259345200162
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Electron spin resonance study of as-deposited and annealed (HfO2)(x)(SiO2)(1-x) high-kappa dielectrics on Si
JOURNAL OF APPLIED PHYSICS
2007; 101 (1)
View details for DOI 10.1063/1.2402974
View details for Web of Science ID 000243585200047
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An integrated phase change memory cell with Ge nanowire diode for cross-point memory
Symposium on VLSI Technology 2007
JAPAN SOCIETY APPLIED PHYSICS. 2007: 98–99
View details for Web of Science ID 000250539900038
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High performance, strained-Ge, heterostructure pMOSFETs
12th International Conference on Simulation of Semiconductor Processes and Devices
SPRINGER-VERLAG WIEN. 2007: 21–24
View details for Web of Science ID 000252105600005
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A semiclassical model of dielectric relaxation in glasses
JOURNAL OF APPLIED PHYSICS
2006; 100 (12)
View details for DOI 10.1063/1.2397323
View details for Web of Science ID 000243157900069
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Results of the search for inspiraling compact star binaries from TAMA300's observation in 2000-2004
PHYSICAL REVIEW D
2006; 74 (12)
View details for DOI 10.1103/PhysRevD.74.122002
View details for Web of Science ID 000243171800009
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Silicon-based photonic crystal nanocavity light emitters
APPLIED PHYSICS LETTERS
2006; 89 (22)
View details for DOI 10.1063/1.2396903
View details for Web of Science ID 000242538500001
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Templated germanium nanowire synthesis using oriented mesoporous organosilicate thin films
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B
2006; 24 (5): 2220-2224
View details for DOI 10.1116/1.2244543
View details for Web of Science ID 000241476500008
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Charge trapping in high-k gate stacks due to the bilayer structure itself
IEEE TRANSACTIONS ON ELECTRON DEVICES
2006; 53 (8): 1858-1867
View details for DOI 10.1109/TED.2006.877700
View details for Web of Science ID 000239286700015
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Nature of germanium nanowire heteroepitaxy on silicon substrates
JOURNAL OF APPLIED PHYSICS
2006; 100 (2)
View details for DOI 10.1063/1.2219007
View details for Web of Science ID 000239423400124
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Joint LIGO and TAMA300 search for gravitational waves from inspiralling neutron star binaries
PHYSICAL REVIEW D
2006; 73 (10)
View details for DOI 10.1103/PhysRevD.73.102002
View details for Web of Science ID 000237951100005
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High-mobility ultrathin strained Ge MOSFETs on bulk and SOI with low band-to-band tunneling leakage: Experiments
IEEE TRANSACTIONS ON ELECTRON DEVICES
2006; 53 (5): 990-999
View details for DOI 10.1109/TED.2006.872362
View details for Web of Science ID 000237369800005
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High-mobility low band-to-band-tunneling strained-germanium double-gate heterostructure FETs: Simulations
IEEE TRANSACTIONS ON ELECTRON DEVICES
2006; 53 (5): 1000-1009
View details for DOI 10.1109/TED.2006.872367
View details for Web of Science ID 000237369800006
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DNA functionalization of carbon nanotubes for ultrathin atomic layer deposition of high kappa dielectrics for nanotube transistors with 60 mV/decade switching
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
2006; 128 (11): 3518-3519
Abstract
For single-walled carbon nanotube (SWNT) field effect transistors, vertical scaling of high kappa dielectrics by atomic layer deposition (ALD) currently stands at approximately 8 nm with a subthreshold swing S approximately 70-90 mV/decade at room temperature. ALD on as-grown pristine SWNTs is incapable of producing a uniform and conformal dielectric layer due to the lack of functional groups on nanotubes and because nucleation of an oxide dielectric layer in the ALD process hinges upon covalent chemisorption on reactive groups on surfaces. Here, we show that by noncovalent functionalization of SWNTs with poly-T DNA molecules (dT40-DNA), one can impart functional groups of sufficient density and stability for uniform and conformal ALD of high kappa dielectrics on SWNTs with thickness down to 2-3 nm. This enables approaching the ultimate vertical scaling limit of nanotube FETs and reliably achieving S approximately 60 mV/decade at room temperature, and S approximately 50 mV/decade in the band-to-band tunneling regime of ambipolar transport. We have also carried out microscopy investigations to understand ALD processes on SWNTs with and without DNA functionalization.
View details for DOI 10.1021/ja058836v
View details for Web of Science ID 000236299700024
View details for PubMedID 16536515
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Effect of oxide overlayer formation on the growth of gold catalyzed epitaxial silicon nanowires
APPLIED PHYSICS LETTERS
2006; 88 (10)
View details for DOI 10.1063/1.2179370
View details for Web of Science ID 000235905800071
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Theoretical investigation of performance in uniaxially- and biaxially-strained Si, SiGe and Ge double-gate p-MOSFETs
IEEE International Electron Devices Meeting
IEEE. 2006: 681–684
View details for Web of Science ID 000247357700170
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Silicon-based photonic crystal nanocavity light emitters
19th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society
IEEE. 2006: 240–241
View details for Web of Science ID 000246167900122
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Upper limits from the LIGO and TAMA detectors on the rate of gravitational-wave bursts
PHYSICAL REVIEW D
2005; 72 (12)
View details for DOI 10.1103/PhysRevD.72.122004
View details for Web of Science ID 000234274900008
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Ultra-high-yield growth of vertical single-walled carbon nanotubes: Hidden roles of hydrogen and oxygen
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2005; 102 (45): 16141-16145
Abstract
An oxygen-assisted hydrocarbon chemical vapor deposition method is developed to afford large-scale, highly reproducible, ultra-high-yield growth of vertical single-walled carbon nanotubes (V-SWNTs). It is revealed that reactive hydrogen species, inevitable in hydrocarbon-based growth, are damaging to the formation of sp(2)-like SWNTs in a diameter-dependent manner. The addition of oxygen scavenges H species and provides a powerful control over the C/H ratio to favor SWNT growth. The revelation of the roles played by hydrogen and oxygen leads to a unified and universal optimum-growth condition for SWNTs. Further, a versatile method is developed to form V-SWNT films on any substrate, lifting a major substrate-type limitation for aligned SWNTs.
View details for DOI 10.1073/pnas.0507064102
View details for PubMedID 16263931
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Characteristics and mechanism of tunable work function gate electrodes using a bilayer metal structure on SiO2 and HfO2
IEEE ELECTRON DEVICE LETTERS
2005; 26 (7): 445-447
View details for DOI 10.1109/LED.2005.851232
View details for Web of Science ID 000230150400007
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An atomic force microscope study of surface roughness of thin silicon films deposited on SiO2
Silicon Nanoelectronics Workshop 2004
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. 2005: 303–11
View details for DOI 10.1109/TNANO.2005.847007
View details for Web of Science ID 000229056800002
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Ab initio study of metal gate electrode work function
APPLIED PHYSICS LETTERS
2005; 86 (7)
View details for DOI 10.1063/1.1865349
View details for Web of Science ID 000227439400092
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Edge-defined 90nm TFTs with adjustable V-T in a 3-D compatible process
IEEE International SOI Conference
IEEE. 2005: 27–29
View details for Web of Science ID 000234923200006
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Fabrication and characterization of CMOSFETs on porous silicon for novel device layer transfer
IEEE International Electron Devices Meeting
IEEE. 2005: 695–698
View details for Web of Science ID 000236225100158
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Physical mechanisms of electron mobility enhancement in uniaxial stressed MOSFETs and impact of uniaxial stress engineering in ballistic regime
IEEE International Electron Devices Meeting
IEEE. 2005: 135–138
View details for Web of Science ID 000236225100029
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New constraint for Vth optimization for sub 32nm node CMOS gates scaling
IEEE International Electron Devices Meeting
IEEE. 2005: 1049–1052
View details for Web of Science ID 000236225100240
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Low defect ultra-thin fully strained-Ge MOSFET on relaxed Si with high mobility and low band-to-band-tunneling (BTBT)
25th Symposium on VLSI Technology
JAPAN SOCIETY APPLIED PHYSICS. 2005: 82–83
View details for Web of Science ID 000234973100032
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Preferential growth of semiconducting single-walled carbon nanotubes by a plasma enhanced CVD method
NANO LETTERS
2004; 4 (2): 317-321
View details for DOI 10.1021/nl035097c
View details for Web of Science ID 000188965700025
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Power optimization of future transistors and a resulting global comparison standard
50th IEEE International Electron Devices Meeting
IEEE. 2004: 415–418
View details for Web of Science ID 000227158500094
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Experimental study of biaxial and uniaxial strain effects on carrier mobility in bulk and ultrathin-body SOI MOSFETs
50th IEEE International Electron Devices Meeting
IEEE. 2004: 229–232
View details for Web of Science ID 000227158500051
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Critical evaluation of the safety of recombinant human growth hormone administration: Statement from the growth hormone research society
JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM
2001; 86 (5): 1868-1870
View details for Web of Science ID 000168731600004
View details for PubMedID 11344173
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Consensus guidelines for the diagnosis and treatment of growth hormone (GH) deficiency in childhood and adolescence: Summary statement of the GH Research Society
JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM
2000; 85 (11): 3990-3993
View details for Web of Science ID 000166992000008
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Analysis of the potential distribution in the channel region of a platinum silicided source drain metal oxide semiconductor field effect transistor
APPLIED PHYSICS LETTERS
1999; 74 (22): 3407-3409
View details for Web of Science ID 000080474300055
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EXPERIMENTAL INVESTIGATION OF A PTSI SOURCE AND DRAIN FIELD-EMISSION TRANSISTOR
APPLIED PHYSICS LETTERS
1995; 67 (10): 1420-1422
View details for Web of Science ID A1995RR44000027