Article
Chemistry, Analytical
Michele Pirro, Xuanyi Zhao, Bernard Herrera, Pietro Simeoni, Matteo Rinaldi
Summary: This study analyzes the impact of substrate-RF application on the material properties of doped aluminum nitride and demonstrates the possibility of modifying leakage, breakdown, coercive fields, and polarization charge by adjusting the lattice cell. This provides a potential solution to alleviate the limitations of the material.
Article
Physics, Applied
Pauline Dufour, Thomas Maroutian, Maxime Vallet, Kinnary Patel, Andre Chanthbouala, Charlotte Jacquemont, Lluis Yedra, Vincent Humbert, Florian Godel, Bin Xu, Sergey Prosandeev, Laurent Bellaiche, Mojca Otonicar, Stephane Fusil, Brahim Dkhil, Vincent Garcia
Summary: The antiferroelectric state of 45-nm-thick epitaxial thin films of PbZrO3 is observed through the characteristic structural periodicity of dipoles and the double hysteresis of the polarization-electric field response. A transition to a ferroelectric-like state is found to occur in a large temperature window. Atomistic simulations confirm the presence and origin of the ferroelectric state in the films. Electric-field-induced ferroelectric transitions are detected via piezoresponse force microscopy.
APPLIED PHYSICS REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Yang Zhang, Hui Wang, Koki Tachiyama, Tsukasa Katayama, Yinghao Zhu, Si Wu, Hai-Feng Li, Jinghong Fang, Qin Li, Yun Shi, Ling Wang, Zhengqian Fu, Fangfang Xu, Jianding Yu, Shintaro Yasui, Mitsuru Itoh
Summary: In this study, epsilon-Fe2O3 single crystals were successfully synthesized by codoping with Ga3+ and Sc3+, demonstrating both room-temperature ferrimagnetism and spontaneous ferroelectric polarization. The single crystals displayed strong magnetic anisotropy along the a-axis at 300 K, with magnetic transition temperature and coercive field decreasing with increasing x. Furthermore, a magnetic-field-induced modulation of polarization was observed at a relatively high temperature of 150 K with a magnetoelectric coefficient of (2-5) x 10(-11) S/m.
CRYSTAL GROWTH & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
Xianlong Cheng, Chao Zhou, Baichen Lin, Zhenni Yang, Shanquan Chen, Kelvin H. L. Zhang, Zuhuang Chen
Summary: Fluorite-structured Hf0.5Zr0.5O2 (HZO) thin films have gained attention for their good CMOS-compatibility and robust ferroelectricity. However, the challenges of high leakage current and poor endurance hinder the application of HZO in microelectronic devices. This study investigates the electric properties of Pt/HZO/La0.7Sr0.3MnO3 (LSMO) heterostructures and finds that the leakage mechanism is dominated by Schottky emission. By post-annealing in oxygen atmosphere, the barrier height can be increased, effectively reducing leakage current and improving endurance.
APPLIED MATERIALS TODAY
(2023)
Article
Chemistry, Multidisciplinary
Muhammad Sheeraz, Min-Hyoung Jung, Yoon Ki Kim, Nyun-Jong Lee, Seyeop Jeong, Jin San Choi, Yong Jin Jo, Shinuk Cho, Ill Won Kim, Young-Min Kim, Sanghoon Kim, Chang Won Ahn, Sang Mo Yang, Hu Young Jeong, Tae Heon Kim
Summary: In this study, highly crystalline SrRuO3 freestanding membranes were successfully fabricated using new infinite-layer perovskite SrCuO2 sacrificial layers. The SrRuO3/SrCuO2 bilayer thin films were epitaxially grown on SrTiO3 (001) substrates, and the SrRuO3 layer was chemically exfoliated by etching the SrCuO2 template layer. The exfoliated SrRuO3 membranes were mechanically transferred to nonoxide substrates for subsequent BaTiO(3) film growth. Finally, freestanding heteroepitaxial junctions of ferroelectric BaTiO3 and metallic SrRuO3 were realized, exhibiting enhanced piezoelectric responses in mixed ferroelectric domain states.
Article
Physics, Applied
Wanwang Yang, Li Chen, Minghua Li, Fei Liu, Xiaoyan Liu, Chen Liu, Jinfeng Kang
Summary: This study investigates the effect of stress on the leakage current in ferroelectric Al0.7Sc0.3N films using experiments and DFT calculations. The study reveals that stress increases the leakage current and provides guidelines for optimizing ferroelectric devices using stress engineering.
APPLIED PHYSICS LETTERS
(2023)
Review
Nanoscience & Nanotechnology
Kwan-Ho Kim, Ilya Karpov, Roy H. H. Olsson, Deep Jariwala
Summary: Ferroelectric materials, similar to magnets, have attracted continuous research interest due to their spontaneous electric polarization that is non-volatile and programmable. While magnets have been widely used in modern information technology, applications of ferroelectric materials are still limited. Recent advancements in wurtzite-structured ferroelectric materials have provided new opportunities for their deployment in microelectronics hardware, particularly in memory and storage-based devices. This Review focuses on the recent progress and applications of wurtzite-structured ferroelectric materials in microelectronic hardware, comparing them with existing fluorite-structured ferroelectric materials.
NATURE NANOTECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Shinnosuke Yasuoka, Ryoichi Mizutani, Reika Ota, Takahisa Shiraishi, Takao Shimizu, Masato Uehara, Hiroshi Yamada, Morito Akiyama, Hiroshi Funakubo
Summary: The effect of pure mechanical strain on the ferroelectric properties of (Al0.8Sc0.2)N films deposited on different thermal expansion coefficient substrates was investigated. It was found that the mechanical lattice strains could be controlled by using substrates with different thermal expansion coefficients. The changes in remanent polarization and coercive field values could be understood by crystal anisotropy.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
Article
Multidisciplinary Sciences
Martin F. Sarott, Marta D. Rossell, Manfred Fiebig, Morgan Trassin
Summary: This study demonstrates the ability to continuously modulate the remanent polarization at the nanoscale in PbZr0.52Ti0.48O3 films by driving the system towards the instability at the morphotropic phase boundary, achieving multilevel switching.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Alexandre Silva, Ignasi Fina, Florencio Sanchez, Jose P. B. Silva, Luis Marques, Veniero Lenzi
Summary: We investigated the influence of La content on the structural and ferroelectric properties of epitaxial HfO2 films. It was found that 2-5 at. % La-doped HfO2 films exhibit optimum remanent polarization and reduced coercive field. Density functional theory calculations supported the experimental results and revealed that the polarization switching in epitaxial La:HfO2 films can be understood based on the synergetic contribution of a non-ferroelectric monoclinic phase and La doping itself.
MATERIALS TODAY PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Yuki Tashiro, Takao Shimizu, Takanori Mimura, Hiroshi Funakubo
Summary: The study of YO1.5-doped HfO2 films reveals that different doping levels affect the crystal structure, with high temperatures promoting phase transitions and electric-field-induced phase transitions showing coupled characteristics.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Chemistry, Physical
Kaede Makiuchi, Fumio Kawamura, Junjun Jia, Yelim Song, Shunichiro Yata, Hitoshi Tampo, Hidenobu Murata, Naoomi Yamada
Summary: Single-phase MgSnN2 thin films with rocksalt structure were successfully synthesized through high-pressure heat treatment and epitaxial growth. These films show potential as optoelectronic materials for light-emitting diodes and tandem solar cells.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Min Zhang, Chaoyong Deng
Summary: The evolution of dynamic hysteresis with electrical field amplitude and frequency in BTO single crystal films prepared by PLD was systematically investigated. A noticeable transition from low-frequency to high-frequency behavior was observed, with domain motion frequency dependence identified as the cause of the dynamic hysteresis loop scaling behavior.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Marijn W. van de Putte, Mark Huijben
Summary: To enable miniaturized thermoelectric energy generation devices for wireless sensors, high-quality thin film architectures are needed. This study explores the impact of epitaxial alignment between the orthorhombic SnSe crystal structure and the orthorhombic DyScO3 substrate. The achieved (100)-oriented single crystalline SnSe thin films exhibit the formation of two domain types, and show a sudden increase in electrical conductivity above 400 K. The epitaxial alignment enhances thermoelectric performance and enables the realization of miniaturized TEG devices.
APPLIED SURFACE SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Hong Pang, Cedric Bourges, Rajveer Jha, Takahiro Baba, Naoki Sato, Naoyuki Kawamoto, Tetsuya Baba, Naohito Tsujii, Takao Mori
Summary: In this study, a rarely reported metastable wurtzite-type phase of CuFeS2 thin film was successfully obtained and a phase transition between the metastable wurtzite and the chalcopyrite phase was observed. The phase change significantly affected the thermoelectric properties. It was found that the wurtzite phase could be recovered and stabilized between room temperature and 473 K. Additionally, the reduced thermal conductivity of the thin film compared with bulk was demonstrated, which was correlated with the polycrystal sizes.
Article
Energy & Fuels
Imran S. Khan, Tursun Ablekim, Deborah L. McGott, Brian Good, Craig L. Perkins, Wyatt K. Metzger, Andriy Zakutayev
Summary: The study demonstrates a high-throughput approach to codesign chemical compositions in alloyed MgxZn1-xO/CdSeyTe1-y thin-film solar cells, with efficiency up to 17.7% related to elemental compositions.
Article
Chemistry, Physical
Andrea Crovetto, Thomas Unold, Andriy Zakutayev
Summary: Through thin-film experiments, electronic structure calculations, and semiclassical Boltzmann transport theory, we find that Cu3P is an intrinsic semimetal, while experimentally realizable Cu3-xP films are p-type semimetals due to copper vacancy doping. Small-sized Cu3-xP samples may become semiconductors as a result of quantum confinement effects. This study demonstrates the suitability of reactive sputter deposition for detailed high-throughput studies of emerging metal phosphides.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Meagan C. C. Papac, Jake Huang, Andriy Zakutayev, Ryan O'Hayre
Summary: Through combinatorial experimental methods and multidimensional Bayesian analysis, the dependency of triple ionic-electronic conducting oxides (TIECs) on chemical composition and environmental conditions in high-temperature electrochemical applications is investigated. The study reveals that Co-rich compositions achieve the lowest overall polarization resistance, while Fe substitution may increase polarization resistance. This work provides a map of electronic properties of TIEC materials under relevant conditions, and demonstrates a unique approach to studying TIECs combining combinatorial experiments and Bayesian analysis.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Electrochemistry
Jake Huang, Neal P. Sullivan, Andriy Zakutayev, Ryan O'Hayre
Summary: The distribution of relaxation times (DRT) is a versatile method for analyzing electrochemical impedance spectroscopy (EIS) data from complex devices. It does not require a generative model, making it useful when the system's governing principles are not fully understood. However, DRT estimation is an ill-posed problem that relies on subjective choices of regularization and tuning, leading to the risk of misleading interpretations of the data.
ELECTROCHIMICA ACTA
(2023)
Article
Chemistry, Physical
Mirjana Dimitrievska, Alexander P. Litvinchuk, Andriy Zakutayev, Andrea Crovetto
Summary: In this work, a reference Raman spectrum of CuP2 was provided, and all Raman active modes were analyzed from both experimental and theoretical perspectives. The phonon density of states and phonon dispersions were also calculated, providing a microscopic understanding of the phonon lines. The agreement between the experimental and DFT-calculated Raman spectra of CuP2 was found, which can be used as a reference for future investigations on this material.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Hanzhe Liu, Jonathan M. Michelsen, Jocelyn L. Mendes, Isabel M. Klein, Sage R. Bauers, Jake M. Evans, Andriy Zakutayev, Scott K. Cushing
Summary: Transient extreme ultraviolet (XUV) spectroscopy has the ability to separate photoexcited electron and hole dynamics with element specificity, making it a valuable tool for characterizing solar energy materials. In this study, surface-sensitive femtosecond XUV reflection spectroscopy is used to measure the dynamics of photoexcited electron, hole, and band gap in ZnTe, a promising photocathode for CO2 reduction. By developing an ab initio theoretical framework, the complex transient XUV spectra are assigned to the electronic states of the material, allowing the identification of relaxation pathways and quantification of their time scales in photoexcited ZnTe.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Crystallography
Victor Regis, Matej Sadl, Geoff Brennecka, Andraz Bradesko, Urban Tomc, Hana Ursic
Summary: With the development of the microelectronic industry, multifunctional materials are in high demand, and Al2O3 is widely used due to its mechanical and thermal stabilities as well as chemical inertness. However, its modest permittivity requires large effective areas or extremely thin layers for large capacitance. In this study, composites of Al2O3/Al with different volume ratios were prepared using the aerosol deposition method, achieving a significant enhancement in dielectric permittivity. Our results demonstrate novel possibilities for the applications of Al2O3-based materials in the microelectronic industry.
Article
Materials Science, Ceramics
Keisuke Yazawa, Daniel Drury, John Hayden, Jon-Paul Maria, Susan Trolier-McKinstry, Andriy Zakutayev, Geoff L. Brennecka
Summary: The study focuses on the asymmetric wake-up behavior of Wurtzite ferroelectric materials, which plays a crucial role in the reliable operation of devices. Through various experimental methods, it was found that the gradual opening of polarization hysteresis loops during wake-up is attributed to the increase in domain-wall density and/or domain-wall mobility with electric field cycles opposite to the growth polarity. The insights gained from this study will provide guidance for the design of reliable devices based on these materials.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Nanoscience & Nanotechnology
Davi M. M. Febba, Kevin R. R. Talley, Kendal Johnson, Stephen Schaefer, Sage R. R. Bauers, John S. S. Mangum, Rebecca W. W. Smaha, Andriy Zakutayev
Summary: We report the design and implementation of an autonomous workflow for sputter deposition of thin films with controlled composition. By minimizing the absolute error between desired and measured optical emission signals, we demonstrate the reliability of this method in synthesizing thin films with specific compositions.
Article
Materials Science, Multidisciplinary
Christopher L. Rom, Rebecca W. Smaha, Callan A. Knebel, Karen N. Heinselman, James R. Neilson, Sage R. Bauers, Andriy Zakutayev
Summary: Solid state synthesis of nitride materials can lead to different crystal structures compared to thin film synthesis. This study explores the chemical phase space of Mg-W-N using rapid thermal annealing, revealing new phases and demonstrating how polymorphic transformations can be controlled using this method.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Keisuke Yazawa, John Hayden, Jon-Paul Maria, Wanlin Zhu, Susan Trolier-McKinstry, Andriy Zakutayev, Geoff L. Brennecka
Summary: This article describes and explains the anomalous polarization reversal behavior of wurtzite-structured nitride thin film ferroelectrics Al0.7Sc0.3N and Al0.94B0.06N under high electric fields and proposes a general model that can be applied to other nucleation and growth transitions. The work provides a more comprehensive description of nucleation and growth kinetics applicable to any system and specifically addresses the abrupt polarization reversal behavior in new wurtzite-structured ferroelectrics through two related but distinct scenarios.
MATERIALS HORIZONS
(2023)
Article
Chemistry, Physical
Rachel Woods-Robinson, Kristin A. Persson, Andriy Zakutayev
Summary: This study investigates the phase space of barium tin sulfide (Ba-Sn-S) using experimental and theoretical methods, exploring phase behavior, electronic properties, and optical absorption properties. The findings highlight the potential of Ba-Sn-S materials for solar energy harvesting and semiconductor applications.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Joe Willis, Rekha R. Schnepf, Karen N. Heinselman, Bartomeu Monserrat, Thomas Unold, Andriy Zakutayev, David O. Scanlon, Andrea Crovetto, Ivona Bravic
Summary: Phosphides, as interesting candidates for hole transport materials and p-type transparent conducting applications, show potential for higher mobilities compared to their oxide counterparts. In this study, we report the successful deposition of phase-pure p-type CaCuP thin films with high intrinsic hole concentration and hole mobility. Copper vacancies are identified as the main source of conductivity, leading to improved electronic properties. However, the optical transparency of the films is lower than expected, which may be attributed to crystalline imperfections.
