Article
Engineering, Electrical & Electronic
Adam Charnas, Jackson Anderson, Jie Zhang, Dongqi Zheng, Dana Weinstein, Peide D. D. Ye
Summary: The remarkable dc performance of ultra thin indium oxide transistors allows for high-performance back-end-of-line (BEOL) and monolithically integrated logic and memory devices. The radio frequency (RF) performance of these transistors with high working frequency is characterized for the first time, reporting a new record high cutoff frequency (fT) and maximum oscillation frequency (fmax) among amorphous metal-oxide-semiconductor transistors. Detailed statistical measurements provide insight into optimizing device parasitics and future scaling trends.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Nanoscience & Nanotechnology
Dongil Ho, Sunwoo Choi, Hyunwoo Kang, Byungkyu Park, Minh Nhut Le, Sung Kyu Park, Myung-Gil Kim, Choongik Kim, Antonio Facchetti
Summary: Solution-processed metal-oxide thin-film transistors (TFTs) with different metal compositions were investigated for radiation hardness against ionizing radiation exposure. The amorphous zinc-indium-tin oxide (Zn-In-Sn-O or ZITO) was found to be an optimal radiation-resistant channel layer of TFTs due to its structural plasticity, defect tolerance, and high electron mobility. In situ irradiation experiments revealed three degradation mechanisms, including increase in channel conductivity, charge buildup in the interface and dielectric, and trap-assisted tunneling in the dielectric. By employing a radiation-resistant ZITO channel, a thin SiO2 dielectric, and a passivation layer, oxide-based TFTs demonstrated excellent stability under real-time gamma-ray irradiation.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Engineering, Electrical & Electronic
Meng-Hung Tsai, Chia-Jung Shih, Che-Wei Chang, Yu-Tseng Chu, You-Shen Wu, Cheng-Liang Huang
Summary: In this work, we propose that the band gap of amorphous Nb2O5 thin films can be narrowed, and this concept is validated by fabricating amorphous Nb2O5 based resistive random-access memory devices. The effects of Mn dopants and temperature on the conduction mechanism of the Nb2O5-based devices are investigated, and it is demonstrated that oxygen vacancies dominate the conduction mechanism of Mn-doped Nb2O5-based devices. X-ray photoelectron spectroscopy analysis reveals that the addition of Mn promotes the oxidation of Nb, offering significant benefits for improving the performance of RRAM memory.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Min Seong Kim, Hyung Tae Kim, Hyukjoon Yoo, Dong Hyun Choi, Jeong Woo Park, Tae Sang Kim, Jun Hyung Lim, Hyun Jae Kim
Summary: This study suggests that introducing an oxygen scavenger layer (OSL) in a-IGZO TFT can significantly improve its electrical characteristics and stability, especially at low temperatures. The enhancement is mainly attributed to the presence of hafnium (Hf) in the OSL, which absorbs oxygen ions to address interface issues between the front channel and OSL.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Engineering, Electrical & Electronic
William Cheng-Yu Ma, Cai-Jia Tsai
Summary: The independent dual-gate operation improves performance and reliability of the JL-TFT, but may also cause more serious damages. The back gate voltage operation mode provides a wide threshold voltage tuning range, but it is important to note that positive top gate voltage stress may lead to more serious reliability issues.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Engineering, Electrical & Electronic
Axel Laborieux, Marc Bocquet, Tifenn Hirtzlin, Jacques-Olivier Klein, Etienne Nowak, Elisa Vianello, Jean-Michel Portal, Damien Querlioz
Summary: The paper focuses on the implementation of ternary neural networks and proposes a two-transistor/two-resistor memory architecture for achieving high energy efficiency at low supply voltage, while studying the bit error rate. Experimental results demonstrate that ternary neural networks can significantly improve neural network performance and exhibit immunity to bit errors.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS
(2021)
Article
Nanoscience & Nanotechnology
Duho Kim, Yu-Rim Jeon, Boncheol Ku, Chulwon Chung, Tae Heun Kim, Sanghyeok Yang, Uiyeon Won, Taeho Jeong, Changhwan Choi
Summary: Neuromorphic computing has attracted attention for overcoming the limitations of von-Neumann computing, with analog synaptic devices playing a crucial role in hardware-based artificial neuromorphic devices. This study demonstrates the synaptic characteristics of a ferroelectric material-based thin-film transistor, showing successful emulation of short-term and long-term plasticity. The research suggests that ferroelectric transistors can serve as alternative artificial synapses with high linearity and pattern recognition accuracy.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Physics, Applied
Na Xiao, Saravanan Yuvaraja, Dhanu Chettri, Zhiyuan Liu, Yi Lu, Chehao Liao, Xiao Tang, Xiaohang Li
Summary: Annealing under different atmospheres can improve the electrical performance of indium oxide thin-film transistors by modifying the density of oxygen vacancies and hydroxyl/carbonate groups. The annealed thin-film transistors exhibit high field-effect mobility, high on/off current ratio, and controlled threshold voltage.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Mengwei Si, Yaoqiao Hu, Zehao Lin, Xing Sun, Adam Charnas, Dongqi Zheng, Xiao Lyu, Haiyan Wang, Kyeongjae Cho, Peide D. Ye
Summary: This work demonstrates enhancement-mode field-effect transistors using an atomically-deposited amorphous In2O3 channel with thickness as low as 0.7 nm. The controllable thickness of In2O3 at an atomic scale allows for the design of sufficient 2D carrier density in the channel, affecting threshold voltage and channel carrier density. The model of trap neutral level (TNL) explains how the Fermi level aligns in the conduction band of In2O3 due to the quantum confinement effect, as confirmed by density function theory (DFT) calculations.
Review
Chemistry, Multidisciplinary
Gregory Soon How Thien, Mohd Arif Mohd Sarjidan, Noor Azrina Talik, Boon Tong Goh, Boon Kar Yap, Zhicai He, Kah-Yoong Chan
Summary: This review discusses the impact of top electrode (TE) dependence on resistive switching (RS) characteristics in different materials used as potential candidates for memory devices. The relevance and importance of electrode dependence in the design of halide perovskite (HP) memories are highlighted through the exploration of electrode modification advances and techniques.
MATERIALS CHEMISTRY FRONTIERS
(2022)
Article
Materials Science, Multidisciplinary
S. Arulkumar, S. Parthiban, J. Y. Kwon, Y. Uraoka, J. P. S. Bermundo, Arka Mukherjee, Bikas C. Das
Summary: In this study, amorphous silicon indium oxide thin films were deposited using a sputtering process at room temperature for thin-film transistor (TFT) active channel applications. The study confirmed the amorphous nature and surface roughness of the deposited films and investigated the effect of different oxygen partial pressures on film properties. The results showed that the annealed films exhibited good performance and stability.
Article
Chemistry, Multidisciplinary
Hyeonju Lee, Dongwook Kim, Hyunji Shin, Jin-Hyuk Bae, Jaehoon Park
Summary: In order to achieve oxide semiconductor-based complementary circuits and improve transparent display applications, it is necessary to study the electrical properties of p-type oxide semiconductors and the performance of p-type oxide thin-film transistors (TFTs). This study examines the effects of post-UV/ozone treatment on the structural and electrical characteristics of copper oxide (CuO) semiconductor films and TFT performance. The results show that post-UV/ozone treatment can significantly enhance the electrical properties of CuO films and CuO TFTs by suppressing weak bonding and structural defects.
Article
Materials Science, Multidisciplinary
Masahiro Sugiyama, Sophie Jancke, Takafumi Uemura, Masaya Kondo, Yumi Inoue, Naoko Namba, Teppei Araki, Takanori Fukushima, Tsuyoshi Sekitani
Summary: Interface modification with a specific triptycene molecule can enhance the field-effect mobility of various thienoacene-based OSCs in flexible organic thin-film transistors (OTFTs) and increase the crystal grain size of the OSC films.
ORGANIC ELECTRONICS
(2021)
Article
Chemistry, Physical
Yilin Li, Xuan Zeng, Qiannan Ye, Rihui Yao, Jinyao Zhong, Xiao Fu, Yuexin Yang, Muyun Li, Honglong Ning, Junbiao Peng
Summary: In this study, the influence mechanism of oxygen-related defect states on the performance and stability of high mobility oxide TFT was analyzed by adjusting the oxygen percentage. Through the clever design of homo-junction TFT, devices with high mobility and good stability were achieved.
SURFACES AND INTERFACES
(2022)
Article
Engineering, Electrical & Electronic
Arqum Ali, Md. Mobaidul Islam, Jinbaek Bae, Jin Jang
Summary: Spray pyrolysis is used to fabricate high-performance and crystalline InGaZnO thin-film transistors (TFTs) with excellent stability. The TFTs exhibit high saturation mobility, low subthreshold swing, and high on/off drain current ratio at a growth temperature of 425 degrees C. The dense c-IGZO structure formed by spray pyrolysis contributes to the remarkable performance.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Physics, Applied
Dun-Bao Ruan, Po-Tsun Liu, Kai-Jhih Gan, Yu-Chuan Chiu, Chih-Chieh Hsu, Simon M. Sze
APPLIED PHYSICS LETTERS
(2020)
Article
Nanoscience & Nanotechnology
Kai-Jhih Gan, Po-Tsun Liu, Dun-Bao Ruan, Chih-Chieh Hsu, Yu-Chuan Chiu, Simon M. Sze
Summary: The doping ratio of tungsten significantly influences the memory characteristics of CBRAM, with 15% tungsten doping ratio showing excellent memory properties such as high cycling endurance, low operating voltage, and good retention capability. Additionally, the electrical uniformity and switching behavior of InWZnO devices are improved as the doping ratio of tungsten in the switching layer increases, indicating great potential for high-performance memory devices based on novel material InWZnO.
Article
Engineering, Electrical & Electronic
Che-Chia Chang, Hsin-Hui Huang, Boris Hudec, Ming-Hung Wu, Chih-Cheng Chang, Po-Tsun Liu, Tuo-Hung Hou
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2020)
Article
Engineering, Electrical & Electronic
Dun-Bao Ruan, Kuei-Shu Chang-Liao, Guan-Ting Liu, Yu-Chuan Chiu, Kai-Jhih Gan, Po-Tsun Liu
Summary: A novel low temperature supercritical phase fluid treatment with H₂O₂ cosolvent can lead to significant improvements on Ge nMOSFET by reducing oxygen vacancy and unstable oxidation states, resulting in a device with low equivalent oxide thickness, reduced gate leakage current, high on-current, very low subthreshold swing, high on/off current ratio, small hysteresis, low interface trap density, excellent uniformity, and reliability characteristics.
IEEE ELECTRON DEVICE LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Chih-Chieh Hsu, Po-Tsun Liu, Kai-Jhih Gan, Dun-Bao Ruan, Yu-Chuan Chiu, Simon M. Sze
Summary: This paper investigates the characteristics of CBRAM with IWZO as the switching material in different annealing atmospheres. It is found that annealing in nitrogen atmosphere can significantly improve the endurance cycles and resistance uniformity of the devices, potentially showing promise for future integrated display circuit applications.
Article
Chemistry, Multidisciplinary
Chih-Chieh Hsu, Po-Tsun Liu, Kai-Jhih Gan, Dun-Bao Ruan, Simon M. Sze
Summary: This study investigates the influence of oxygen concentration in the switching layer of conductive bridge random access memory (CBRAM). By manipulating the oxygen flow during sputtering, IWZO films with varying oxygen concentrations and vacancy distributions were fabricated. Results show that CBRAM devices with a specific bilayer stacking sequence exhibit stable resistance distribution and improved endurance.
Article
Physics, Applied
Kai-Jhih Gan, Po-Tsun Liu, Chih-Chieh Hsu, Dun-Bao Ruan, Simon M. Sze
Summary: The study proposed a room temperature high-pressure oxidation technique to manipulate the surface morphology and oxygen depth-profile of the InWZnO film, resulting in improved chemical properties. Devices treated with high-pressure oxidation exhibited uniform resistance states and set/reset repeatability compared to control devices. The mechanism of the effect of high-pressure oxidation treatment on the InWZnO film was comprehensively examined through material analysis and physical model discussions.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Applied
Dun-Bao Ruan, Po-Tsun Liu, Kai-Jhih Gan, Chih-Chieh Hsu, Yu-Chuan Chiu, Chia-Yu Lin, Simon M. Sze
Summary: Various oxygen vacancy passivation treatments were conducted to enhance the thermal resistance and stability of indium gallium zinc oxide material in this study. Analysis of X-ray photoelectron spectroscopy revealed that the supercritical phase fluid-treated sample showed excellent electrical performance, high uniformity, and outstanding thermal stability, making it a promising option for monolithic 3D integration.
APPLIED PHYSICS LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Che-Chia Chang, I-Ting Wang, Hsin-Hui Huang, Boris Hudec, Ming-Hung Wu, Chih-Cheng Chang, Po-Tsun Liu, Tuo-Hung Hou
Summary: The study evaluated strategies to mitigate device breakdown interference, finding that optimizing cell parameters is crucial for reducing interference, and simple redundancy designs cannot compensate for yield loss caused by interference, necessitating careful optimization of array partitioning.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Chemistry, Multidisciplinary
Wan-Ta Fan, Po-Tsun Liu, Po-Yi Kuo, Chien-Min Chang, I-Han Liu, Yue Kuo
Summary: This study found that increasing the oxygen ratio during a-IWO deposition results in a more positive threshold voltage shift and reduced I-ON. Through material measurements and TCAD analysis, it was validated that the transfer characteristics of a-IWO TFT are significantly affected by oxygen flow modulation of O-i defects.
Article
Physics, Applied
Chih-Chieh Hsu, Dun-Bao Ruan, Kuei-Shu Chang Liao, Kai-Jhih Gan, Simon M. Sze, Po-Tsun Liu
Summary: This study investigates the effects of radiation on an amorphous semiconductor InWZnO (IWZO) thin film. The results show that the proportion of oxygen vacancies at the bottom of the film increases with the radiation dose, while the top of the IWZO film is hardly affected. Additionally, the behavior of the IWZO memristor under irradiation is also studied, and it is found that the high resistance state of the memristor is significantly degraded at a radiation dose of 1000 krad. However, the retention time of the IWZO memristor at 85 degrees C with 100 krad is up to 10^4 s.
APPLIED PHYSICS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Dun-Bao Ruan, Kuei-Shu Chang-Liao, Chih-Wei Liu, Yao-Jen Lee, Yu-Hsuan Chien, Bo-Lien Kuo, Yu-Chuan Chiu, Kai-Jhih Gan, Chih-Chieh Hsu, Po-Tsun Liu
Summary: This study demonstrates that performance improvement on Ge nFinFET, pFinFET, and CMOS inverter can be achieved by using a novel low-temperature damage-free supercritical phase fluid (SCF) treatment. The SCF treatment effectively reduces unstable oxidation states, oxygen vacancies, and interface traps, resulting in higher on-off current ratios, lower S.S., higher on current, and better reliability in Ge FinFETs. Furthermore, the Ge FinFET CMOS inverter shows a higher voltage gain with the SCF treatment.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Chih-Chieh Hsu, Po-Tsun Liu, Kai-Jhih Gan, Dun-Bao Ruan, Simon M. Sze
Summary: The electrical performance of electrochemical metallization memory can be significantly improved by applying a bilayer switching structure. A novel amorphous semiconductor InWZnO is used as the main switching layer, and a bilayer structure with HfO2 is fabricated. The optimized bilayer memory with a 3 nm HfO2 layer shows excellent electrical properties and has great potential for next-generation memory in pixel and three-dimensional brain-mimicking IC technology.
Article
Chemistry, Multidisciplinary
Zhen-Hao Li, Tsung-Che Chiang, Po-Yi Kuo, Chun-Hao Tu, Yue Kuo, Po-Tsun Liu
Summary: The authors propose a novel vertically-stacked thin film transistor (TFT) architecture for heterogeneously complementary inverter applications, which consists of p-channel polycrystalline silicon (poly-Si) and n-channel amorphous indium tungsten oxide (a-IWO) with a smaller footprint than a planar structure. The electrical characteristics of the a-IWO TFT, including high mobility, low leakage current, and high on/off current ratio, make it well-suited for complementary metal-oxide-semiconductor technology applications. The vertically-stacked complementary field-effect transistors (CFET) exhibit high energy-efficiency and can increase the circuit density in a chip for next-generation semiconductor technology development.
Article
Engineering, Electrical & Electronic
Po-Yi Kuo, Shao-Chi Lo, Hsiu-Hsuan Wei, Po-Tsun Liu
IEEE JOURNAL OF THE ELECTRON DEVICES SOCIETY
(2020)
