Article
Nanoscience & Nanotechnology
Hongrae Joh, Minhyun Jung, Junghyeon Hwang, Youngin Goh, Taeseung Jung, Sanghun Jeon
Summary: The proposed low-temperature annealing method for crystallization of Hf0.5Zr0.5O2 (HZO) thin films using focused microwave induced annealing technique shows promising results, allowing for the integration of HZO ferroelectric films on flexible substrates with robust ferroelectric properties.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Engineering, Electrical & Electronic
Keyu Bao, Jiajia Liao, Fei Yan, Shijie Jia, Binjian Zeng, Qiong Yang, Min Liao, Yichun Zhou
Summary: This work comprehensively investigates the impact of oxygen vacancies on the reliability of Hf0.5Zr0.5O2 (HZO) ferroelectric capacitors, and achieves enhanced endurance and milder imprint properties by reducing the oxygen vacancy concentration. The alleviation of the built-in field at the ferroelectric/metal interfaces contributes to the superior reliability of the fabricated HZO capacitors with considerable remnant polarization compared with reported ones.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Materials Science, Ceramics
Yuanhang Feng, Zhao Zhao, Ting Wang, Jiaming Li, Ming Xu, Hailiang Jiao, Chen Wang, Haibo Li, Ming Feng
Summary: This study develops a ferroelectric Bi2WO6 photocatalyst with surface oxygen defects, which can efficiently fix nitrogen to produce ammonia under mild conditions. The experiment shows that oxygen defects can provide more reactive sites for N2 adsorption, and the photogenerated charge carriers can be efficiently separated due to the internal electric field. The Bi2WO6 with oxygen defects exhibits higher NH3 yield compared to the original Bi2WO6, especially when assisted by an external magnetic field.
CERAMICS INTERNATIONAL
(2022)
Article
Multidisciplinary Sciences
Pavan Nukala, Majid Ahmadi, Yingfen Wei, Sytze de Graaf, Evgenios Stylianidis, Tuhin Chakrabortty, Sylvia Matzen, Henny W. Zandbergen, Alexander Bjorling, Dan Mannix, Dina Carbone, Bart Kooi, Beatriz Noheda
Summary: This study found that ferroelectricity in hafnia-based thin films is closely related to oxygen voltammetry, as reversible oxygen vacancy migration is observed when the top electrode is oxygen reactive, with electrodes serving as sources and sinks of oxygen, and the dielectric layer acting as a fast conduit at millisecond time scales.
Article
Engineering, Chemical
Xianlong Zhang, Wei Huang, Zhangxun Xia, Mo Xian, Fan Bu, Fengbing Liang, Dexin Feng
Summary: The construction of S-scheme heterojunctions with efficient charge separation is a promising strategy for the development of high-performance photocatalysts. This study successfully synthesized oxygen vacancy-enriched WO3/BiOBr heterojunction nanoflowers and demonstrated their superior photocatalytic performance for the degradation of organic pollutants. The oxygen vacancies in the heterojunction provide accessible reaction sites and facilitate charge separation and transfer, resulting in enhanced photocatalytic activity and reduced aquatic toxicity of the pollutants.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Yeongseok Jeong, Venkateswarlu Gaddam, Youngin Goh, Hunbeom Shin, Sangho Lee, Giuk Kim, Sanghun Jeon
Summary: Hafnia-based ferroelectric materials have recently gained significant attention for future electronic devices. This study reports a high imprinting effect in bilayer stack capacitors by using an optimal TaO insertion layer and high-pressure annealing. The source of the imprint field was found to be tantalum suboxides with doubly positively charged oxygen vacancies. These findings provide a new strategy to enhance the functionality of hafnia-based ferroelectric devices in the future.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Materials Science, Ceramics
Boyi Qu, Daria Eiteneer, Lauren A. Hughes, Jan-Helmut Preusker, Joseph Wood, Wolfgang Rheinheimer, Michael J. Hoffmann, Klaus van Benthem
Summary: During thermal annealing at 1425 degrees C, nominal electric field strengths of 50 V/mm and 150 V/mm were applied along the grain boundary planes of a near 45 degrees (100) twist grain boundary in SrTiO3. Interface expansions of approximately 0.8 nm were observed near the positive electrode for both field strengths. However, annealing at 50 V/mm resulted in a decrease in interface width to around 0.4 nm, while higher field strength caused decomposition of the boundary structure close to the negative electrode. The migration of oxygen due to the applied electric field leads to the observed alteration of grain boundary structures, and at high field strengths, the agglomeration of anion vacancies can cause grain boundary decomposition.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2023)
Article
Engineering, Environmental
Youpeng Li, Lingzhi Zhang
Summary: This study presents an oxygen vacancy-mediated nitrogen doping strategy to modify the surface structure of TiO2 nano-particles, achieving high doping concentration and constructing a TiO2@TiO2-x-SN core@shell heterojunction. This structure favors the diffusion kinetics of Li+ and reduces the band gap, facilitating electron transport. The TiO2@TiO2-x-SN electrode exhibits excellent cycling performance and capacity retention.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Nanoscience & Nanotechnology
Hanan Alexandra Hsain, Younghwan Lee, Suzanne Lancaster, Monica Materano, Ruben Alcala, Bohan Xu, Thomas Mikolajick, Uwe Schroeder, Gregory N. Parsons, Jacob L. Jones
Summary: Hafnia-zirconia (HfO2-ZrO2) solid solution thin films have emerged as viable candidates for electronic applications due to their compatibility with Si technology and demonstrated ferroelectricity at the nanoscale. The oxygen source in atomic layer deposition (ALD) plays a crucial role in determining the impurity concentration and phase composition of HfO2-ZrO2 within metal-ferroelectric-metal devices, notably at the Hf0.5Zr0.5O2 /TiN interface. The interface characteristics of HZO/TiN are fabricated via sequential no-atmosphere processing (SNAP) with either H2O or O-2-plasma to study the influence of oxygen source on buried interfaces. Time-of-flight secondary ion mass spectrometry reveals that HZO films grown via O-2-plasma promote the development of an interfacial TiO(x )layer at the bottom HZO/TiN interface. The presence of the TiOx layer leads to the development of 111-fiber texture in HZO as confirmed by two-dimensional X-ray diffraction (2D-XRD). Structural and chemical differences between HZO films grown via H2O or O-2-plasma were found to strongly affect electrical characteristics such as permittivity, leakage current density, endurance, and switching kinetics. While HZO films grown via H2O yielded a higher remanent polarization value of 25 mu C/cm(2), HZO films grown via O-2-plasma exhibited a comparable Pr of 21 mu C/cm(2) polarization and enhanced field cycling endurance limit by almost 2 orders of magnitude. Our study illustrates how oxygen sources (O-2-plasma or H2O) in ALD can be a viable way to engineer the interface and properties in HZO thin films.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Physics, Multidisciplinary
William S. Huxter, Martin F. Sarott, Morgan Trassin, Christian L. Degen
Summary: Using a scanning nitrogen-vacancy (NV) microscope, we are able to visualize domain patterns in piezoelectric and improper ferroelectric materials by measuring their electric fields. This electric field detection method enables discrimination between different types of surface charge distributions and reconstruction of three-dimensional electric field vector and charge density maps.
Article
Nanoscience & Nanotechnology
Jose P. B. Silva, Ruben Alcala, Uygar E. Avci, Nick Barrett, Laura Begon-Lours, Mattias Borg, Seungyong Byun, Sou-Chi Chang, Sang-Wook Cheong, Duk-Hyun Choe, Jean Coignus, Veeresh Deshpande, Athanasios Dimoulas, Catherine Dubourdieu, Ignasi Fina, Hiroshi Funakubo, Laurent Grenouillet, Alexei Gruverman, Jinseong Heo, Michael Hoffmann, H. Alex Hsain, Fei-Ting Huang, Cheol Seong Hwang, Jorge Iniguez, Jacob L. Jones, Ilya V. Karpov, Alfred Kersch, Taegyu Kwon, Suzanne Lancaster, Maximilian Lederer, Younghwan Lee, Patrick D. Lomenzo, Lane W. Martin, Simon Martin, Shinji Migita, Thomas Mikolajick, Beatriz Noheda, Min Hyuk Park, Karin M. Rabe, Sayeef Salahuddin, Florencio Sanchez, Konrad Seidel, Takao Shimizu, Takahisa Shiraishi, Stefan Slesazeck, Akira Toriumi, Hiroshi Uchida, Bertrand Vilquin, Xianghan Xu, Kun Hee Ye, Uwe Schroeder
Summary: Ferroelectric hafnium and zirconium oxides have shown significant progress in ultralow-power electronic systems, but technical limitations still hinder their application. This article aims to provide a comprehensive overview of the current state, challenges, and prospects for the development of these materials, with the collaboration of experts from different fields.
Article
Nanoscience & Nanotechnology
Hanan Alexandra Hsain, Younghwan Lee, Suzanne Lancaster, Monica Materano, Ruben Alcala, Bohan Xu, Thomas Mikolajick, Uwe Schroeder, Gregory N. Parsons, Jacob L. Jones
Summary: Hafnia-zirconia (HfO2-ZrO2) solid solution thin films show promise for electronic applications due to their compatibility with Si technology and demonstrated ferroelectricity at the nanoscale. The oxygen source in atomic layer deposition (ALD) plays a crucial role in determining the impurity concentration and phase composition of HfO2-ZrO2 within metal-ferroelectric-metal devices. This study found that HZO films grown via O2-plasma promote the development of an interfacial TiOx layer, affecting the structural and chemical differences of the films.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Engineering, Environmental
Liping Chen, Chaoen Li, Yanfeng Zhao, Jiang Wu, Xiaokun Li, Zhanwei Qiao, Ping He, Xuemei Qi, Zhenhao Liu, Guoqing Wei
Summary: Hierarchical metallic Bi modified Bi4O5I2 microspheres with rich oxygen vacancies were successfully prepared using a solvothermal method. The doping of metallic Bi created a built-in electric field to improve carrier separation efficiency. The as-prepared Bi/Bi4O5I2 exhibited excellent catalytic performance, with photo-generated holes and superoxide radicals playing a predominant role in the photocatalytic reaction mechanism.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Electrical & Electronic
Yue Peng, Wenwu Xiao, Yan Liu, Chengji Jin, Xinran Deng, Yueyuan Zhang, Fenning Liu, Yunzhe Zheng, Yan Cheng, Bing Chen, Xiao Yu, Yue Hao, Genquan Han
Summary: HfO2-ZrO2 superlattice ferroelectric capacitor shows improved endurance performance and higher fatigue recovery capability compared to HfZrOx (HZO) device. The superlattice capacitor exhibits lower defect density, higher polarization, and lower leakage current during the cycling of polarization vs. voltage loops. Its endurance is three orders of magnitude higher than the HZO device, and its fatigue can be fully recovered through a short break, unlike the partially recovered fatigue of HZO device.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Green & Sustainable Science & Technology
Huilong Shi, Chunhu Li, Rui Zheng, Liang Wang, Wentai Wang, Junjie Bian, Xiangchao Meng
Summary: A novel GdCrO3/BiVO4 composite was successfully prepared by a combination of solid-state combustion method and hydrothermal treatment, which showed enhanced photocatalytic activity due to the synergistic effect of oxygen vacancies and built-in electric field. The effects of photocatalyst composition, HCOOH dosage, and oxygen vacancy concentration on photocatalytic activity were investigated. The 0.30-GdBiOVs composite exhibited the highest nitrate removal ratio of 97.05% and N2 selectivity of 92.76% in 40 min. The end-products of nitrate nitrogen elimination and the stability of photocatalysts were revealed. The existence of oxygen vacancies and built-in electric field was confirmed by EPR and HRTEM analyses. The possible mechanisms of nitrate nitrogen elimination were clarified.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Engineering, Electrical & Electronic
Jikai Lu, Yue Li, Zihao Xuan, Han Xu, Shuyu Wu, Zhongrui Wang, Shibing Long, Qi Liu, Dashan Shang
Summary: In this study, electrolyte-gated transistors (EGTs) were used as building blocks to implement a spiking neural network (SNN) for efficient information processing. The SNN achieved high accuracy in recognizing handwritten alphabets and demonstrated energy efficiency, paving the way for future energy-efficient neuromorphic computing.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Yongzhou Wang, Hui Xu, Wei Wang, Xumeng Zhang, Zuheng Wu, Ran Gu, Qingjiang Li, Qi Liu
Summary: In this letter, the authors present a configurable neuron constructed using Memristors, which have simple structures and high-density integration. They design a memristor with a tunable threshold and demonstrate its ability to construct configurable neurons with different response curves. The results suggest that the device is suitable for maintaining homeostasis and improving the stability of computing systems.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Zhiwei Dang, Shuxian Lv, Zhaomeng Gao, Meiwen Chen, Yannan Xu, Pengfei Jiang, Yaxin Ding, Peng Yuan, Yuan Wang, Yuting Chen, Qing Luo, Yan Wang
Summary: The endurance performance of TiN Hf0.5Zr0.5O2(HZO) TiN ferroelectric capacitor is greatly improved by increasing the N content of the TiN top electrode. This improvement is attributed to the reduction in defects near the interface in the N-rich capacitor, resulting in reduced leakage current and increased dielectric constant.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Yannan Xu, Yang Yang, Shengjie Zhao, Tiancheng Gong, Pengfei Jiang, Shuxian Lv, Haoran Yu, Peng Yuan, Zhiwei Dang, Yaxin Ding, Yuan Wang, Yuting Chen, Yan Wang, Jinshun Bi, Qing Luo
Summary: This study demonstrates the enhanced breakdown reliability and endurance of 10-nm Hf0.3Zr0.5O2 (HZO) by interrupting grain boundaries with an amorphous Al2O3 layer. The ferroelectric/insulator/ferroelectric structure showed significant reductions in leakage current and improvements in breakdown voltage and time-dependent dielectric breakdown lifetime, achieving >10(10) endurance with more than three orders of magnitude improvement compared to other structures. This work provides an effective strategy for enhancing the reliability of HZO-based ferroelectric devices.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Yannan Xu, Yang Yang, Shengjie Zhao, Tiancheng Gong, Pengfei Jiang, Yuan Wang, Peng Yuan, Zhiwei Dang, Yuting Chen, Shuxian Lv, Yaxin Ding, Yan Wang, Jinshun Bi, Qing Luo
Summary: This article presents a new concept of ferroelectric modulated antiferroelectric memory with independent two-step state switching and large polarization, which is considered as a promising option for multibit storage in advanced technology nodes. The stability and reliability of this new memory concept are verified through mathematical modeling and experimental demonstrations.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Jie Qiu, Jie Cao, Xusheng Liu, Pei Chen, Guan Feng, Xumeng Zhang, Ming Wang, Qi Liu
Summary: Researchers have developed a flexible organic electrochemical transistor-based synaptic device that can directly respond to biological neurotransmitters, exhibiting both short-term and long-term synaptic behaviors. The device shows reliable synaptic response and excellent mechanical flexibility under both flat and bending conditions, providing a promising approach for direct integration with soft biological tissues.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Yuan Wang, Yang Yang, Pengfei Jiang, Shuxian Lv, Boping Wang, Yuting Chen, Yaxin Ding, Tiancheng Gong, Qing Luo
Summary: High-performance ferroelectric devices compatible with the BEOL process were developed by increasing the number of ZrO2 and HfO2 cycles during HZO film growth. The capacitors exhibited high remnant polarization and excellent endurance. The pre-crystallization engineering effectively improved the ferroelectric property of the devices.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Yuan Wang, Yang Yang, Pengfei Jiang, Shuxian Lv, Boping Wang, Yuting Chen, Yaxin Ding, Tiancheng Gong, Bing Chen, Ran Cheng, Xiao Yu, Qing Luo
Summary: In this study, HfO2-based junctionless ferroelectric-gate field effect transistors (FeFETs) and the FeFET NAND memory arrays were proposed and experimentally demonstrated on FDSOI. High performance, including ultra-low leakage (similar to pA) and ultra-high I-PGM/I-ERS ratios (105), can be achieved. Furthermore, the memory functions of the NAND arrays were experimentally demonstrated. FDSOI-based NAND FeFETs will be promising for the next-generation high density, low power memory and edge computing.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Pengfei Jiang, Yang Yang, Wei Wei, Tiancheng Gong, Yuan Wang, Yuting Chen, Yaxin Ding, Shuxian Lv, Boping Wang, Meiwen Chen, Yan Wang, Qing Luo
Summary: This study systematically demonstrates the stress effects of interconnecting metals including Copper and Tungsten on ferroelectric films. The capping layers exert stress on the top electrode, which transfers to the Hf0.5Zr0.5O2 (HZO) layer during annealing, affecting its crystalline state and subsequently enhancing or suppressing ferroelectricity.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Guangjian Wu, Zefeng Zhang, Kun Ba, Xumeng Zhang, Jinhua Zeng, Chongyang Bai, Qi Liu, Jianlu Wang
Summary: The researchers report a hybrid MoS2/PbS quantum dots-based optoelectronic device with short-term memory properties for in-sensor reservoir computing (RC). They demonstrate that the device can effectively regulate the dynamic temporal photoresponse behavior through the photogating effect induced by incident optical intensity and time. The device shows high accuracy in image classifying and time series prediction, indicating its potential for intelligent edge computing.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Computer Science, Information Systems
Weishuang Liang, Qi Liu, Yebing Gan
Summary: This paper proposes a fractional frequency division phase-locked loop based on phase interpolation and implements it using the TSMC 0.11μm CMOS process. A digital time converter (DTC) module is added to reduce the fractional spurious by phase interpolation. The DTC module is calibration-free, and the error introduced by it is only related to the DAC adopted in the DTC. The proposed FNPLL achieves low power consumption, high accuracy, and low phase noise in both fractional and integer division modes.
Article
Multidisciplinary Sciences
Yuan Wang, Lei Tao, Roger Guzman, Qing Luo, Wu Zhou, Yang Yang, Yingfen Wei, Yu Liu, Pengfei Jiang, Yuting Chen, Shuxian Lv, Yaxin Ding, Wei Wei, Tiancheng Gong, Yan Wang, Qi Liu, Shixuan Du, Ming Liu
Summary: Hafnium oxide-based ferroelectric materials, which can integrate into silicon electronics, show promise for next-generation nanoscale devices. By introducing excess Hf(Zr) atoms into the hollow sites, we stabilize the rhombohedral phase and greatly improve the performance of ferroelectric devices, achieving ultralow coercive field and high endurance. This material discovery holds potential for low-cost and long-life memory chips.
Article
Automation & Control Systems
Wei Wang, Sen Liu, Qingjiang Li, Tuo Shi, Feng Zhang, Haijun Liu, Nan Li, Yongzhou Wang, Yi Sun, Bing Song, Hui Xu, Qi Liu
Summary: A novel Cu/alpha-Si/alpha-C/Pt memristor and direct resistance-coupling logic synthesis scheme for high-efficiency in-memory computing is presented in this study. The memristor exhibits excellent uniformity, fast switching speed, good endurance, and long retention. Complete set of Boolean logic and some derived logic operators are efficiently implemented in the Cu/alpha-Si/alpha-C/Pt crossbar array, demonstrating reconfigurable and parallel logic synthesis.
ADVANCED INTELLIGENT SYSTEMS
(2022)
