- Water additives improve the efficiency of violet perovskite light-emitting diodes MATTER 2023; 6 (7): 2356-2367
- Kinetics and mechanism of light-induced phase separation in a mixed-halide perovskite MATTER 2023; 6 (6): 2052-2065
- Field-Induced Ferroelectric Phase Evolution During Polarization "Wake-Up" in Hf0.5Zr0.5O2 Thin Film Capacitors ADVANCED ELECTRONIC MATERIALS 2023
Nanocrystallite Seeding of Metastable Ferroelectric Phase Formation in Atomic Layer-Deposited Hafnia-Zirconia Alloys.
ACS applied materials & interfaces
Hafnia-based ferroelectric thin films are promising for semiconductor memory and neuromorphic computing applications. Amorphous, as-deposited, thin-film binary alloys of HfO2 and ZrO2 transform to the metastable, orthorhombic ferroelectric phase during post-deposition annealing and cooling. This transformation is generally thought to involve formation of a tetragonal precursor phase that distorts into the orthorhombic phase during cooling. In this work, we systematically study the effects of atomic layer deposition (ALD) temperature on the ferroelectricity of post-deposition-annealed Hf0.5Zr0.5O2 (HZO) thin films. Seed crystallites having interplanar spacings consistent with the polar orthorhombic phase are observed by a plan-view transmission electron microscope in HZO thin films deposited at an elevated ALD temperature. After ALD under conditions that promote formation of these nanocrystallites, high-polarization (Pr > 18 muC/cm2) ferroelectric switching is observed after rapid thermal annealing (RTA) at low temperature (350 °C). These results indicate the presence of minimal non-ferroelectric phases retained in the films after RTA when the ALD process forms nanocrystalline particles that seed subsequent formation of the polar orthorhombic phase.
View details for DOI 10.1021/acsami.2c15047
View details for PubMedID 36384298
- CeO2 Doping of Hf0.5Zr0.5O2 Thin Films for High Endurance Ferroelectric Memories ADVANCED ELECTRONIC MATERIALS 2022
Imaging light-induced phase separation dynamics of inorganic halide perovskites
View details for Web of Science ID 000612090002152