Article
Engineering, Electrical & Electronic
Li Yuan, Shasha Li, Guoxiang Song, Xian wen Sun, Xinan Zhang
Summary: Gallium oxide thin films prepared using the solution process method were studied as gate dielectric for thin-film transistors, showing excellent dielectric performance. The optimized Ga2O3 thin film demonstrated high bias stress stability and impressive performance metrics for low-voltage operation oxide TFTs.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Review
Chemistry, Physical
Zhuping Ouyang, Wanxia Wang, Mingjiang Dai, Baicheng Zhang, Jianhong Gong, Mingchen Li, Lihao Qin, Hui Sun
Summary: This paper summarizes the structure and performance of p-Type oxide TFTs and discusses the progress and challenges in oxide transistor research. The microstructures of three types of p-Type oxides and significant efforts to improve the performance of oxide TFTs are highlighted. Finally, the latest progress and prospects of oxide TFTs based on p-Type oxide semiconductors and other p-Type semiconductor electronic devices are discussed.
Article
Engineering, Electrical & Electronic
Tomas Vincze, Michal Micjan, Milan Pavuk, Patrik Novak, Martin Weis
Summary: A field-effect transistor with cupric oxide films prepared by the sol-gel technique was fabricated, exhibiting semiconductor behavior with p-type conductivity. The sol-gel technique proved to be a suitable low-cost alternative to the sputtering technique for metal-oxide semiconductors.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Nanoscience & Nanotechnology
Mari Napari, Tahmida N. Huq, David J. Meeth, Mikko J. Heikkil, Kham M. Niang, Han Wang, Tomi Iivonen, Haiyan Wang, Markku Leskela, Mikko Ritala, Andrew J. Flewitt, Robert L. Z. Hoye, Judith L. MacManus-Driscoll
Summary: High-performance p-type oxide thin film transistors (TFTs) have great potential for semiconductor applications, but often suffer from low hole mobility and high off-state currents. By applying a thin ALD Al2O3 passivation layer on the Cu2O channel and vacuum annealing, the TFT switching characteristics can be improved. Characterization by TEM-EDX and XPS shows that Al2O3 deposition on Cu2O reduces surface and forms a CuAlO2 interfacial layer. This, along with field-effect passivation, leads to improved TFT performance by reducing trap states and electron accumulation in the off-state.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
V. Ratia-Hanby, E. Isotahdon, X. Yue, P. Malmberg, C. Leygraf, E. Huttunen-Saarivirta
Summary: The surface films formed on pre-oxidized copper in anoxic simulated groundwater with sulphide were characterized using various techniques. The results revealed that the sulphide content in the groundwater significantly influenced the morphology and composition of the surface film.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2023)
Article
Chemistry, Physical
Ablat Abliz, Patigul Nurmamat, Da Wan
Summary: In this study, hetero-structured and self-passivated oxide thin film transistors (TFTs) were fabricated successfully. A rational design achieved a high field-effect mobility and small sub-threshold swing. Experimental observations indicate that the accumulation of free carriers near the aIGZO:N2O/TiO2 interfaces resulted from the transfer of electrons. Additionally, appropriate treatment reduced defects and trap density, and the ultra-thin TiO2 layer acted as a surface passivation layer.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Ya-Hsiang Liang, Saravanan Kumaran, Michael Zharnikov, Yian Tai
Summary: Top gate thin film transistors using solution processes can reduce fabrication costs, but may result in gate leakage. Engineering the IGZO/insulator interface with self-assembled monolayers can effectively reduce leakage current in TFTs.
APPLIED SURFACE SCIENCE
(2021)
Article
Nanoscience & Nanotechnology
I. Sak Lee, Joohye Jung, Dong Hyun Choi, Sujin Jung, Kyungmoon Kwak, Hyun Jae Kim
Summary: A homojunction-structured oxide phototransistor based on mechano-chemically treated IGZO absorption layer exhibited outstanding optoelectronic characteristics and sensitivity, making it suitable for optical sensor applications.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Materials Science, Ceramics
Hyeong Jin Park, Taikyu Kim, Min Jae Kim, Hojae Lee, Jun Hyung Lim, Jae Kyeong Jeong
Summary: In this study, high-performance polycrystalline IGO TFTs were successfully fabricated at a low temperature with outstanding electrical characteristics and high stability. The density of oxygen plasma plays a crucial role in the crystalline quality of the IGO thin film.
CERAMICS INTERNATIONAL
(2022)
Article
Materials Science, Multidisciplinary
Liuhui Lei, Wei Dou, Xiaomin Gan, Jia Yang, Wei Hou, Xing Yuan, Weichang Zhou, Dongsheng Tang
Summary: CuSCN-based TFTs with solution-processed chitosan electrolyte are fabricated, demonstrating low operation voltage and high gate capacitance. The threshold voltage, on/off ratio, and field-effect mobility are characterized. The threshold voltage of CuSCN-based TFTs can be significantly changed by laser or annealing treatment. In addition, NAND logic function is implemented for the first time on CuSCN-based TFTs, opening up new possibilities for inorganic semiconductors and logic applications.
RESULTS IN PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Chihun Sung, Sooji Nam, Sung Haeng Cho
Summary: In this study, a new fabrication methodology was proposed to enable high-performance TFT with submicron channel length, exceeding the resolution limit of conventional photolithography. The fabricated Al-doped InZnSnO TFTs exhibited excellent performance characteristics, making them suitable for high-performance large-area electronics.
IEEE ELECTRON DEVICE LETTERS
(2021)
Article
Nanoscience & Nanotechnology
Zhi-Yue Li, Shu-Mei Song, Wan-Xia Wang, Jian-Hong Gong, Yang Tong, Ming-Jiang Dai, Song-Sheng Lin, Tian-Lin Yang, Hui Sun
Summary: In this study, homojunction thin-film transistors (TFTs) with amorphous indium gallium zinc oxide (a-IGZO) as active channel layers were fabricated by RF magnetron sputtering. The effect of oxygen partial pressure on the properties of IGZO thin films was investigated. It was found that the resistivity of IGZO thin films increases with higher oxygen partial pressure. Optimal electrical characteristics were observed in homojunction IGZO TFTs with an oxygen partial pressure of 1.96%.
Article
Engineering, Electrical & Electronic
S. Arulkumar, S. Parthiban, J. Y. Kwon
Summary: The room temperature sputtered indium silicon oxide thin-films were annealed at various temperatures and studied for thin-film transistor (TFT) active channel layer application. The results showed that the annealing temperature had a significant influence on the structure and properties of the thin films, and the highest mobility was achieved at an annealing temperature of 200 degrees Celsius.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Engineering, Electrical & Electronic
Maria Isabel Pintor-Monroy, Martin Gregorio Reyes-Banda, Carlos Avila-Avendano, Manuel A. Quevedo-Lopez
Summary: In this study, a simple and cost-effective method for fabricating thin film transistors (TFTs) based on undoped amorphous Ga2O3 thin films deposited at room temperature by magnetron sputtering is discussed. The control of Ga2O3 thin film resistivity over a wide range is demonstrated by controlling the deposition power and pressure. These TFTs exhibit promising characteristics and have been evaluated as phototransistors under DUV radiation, showing high rejection ratio, responsivity, gain, detectivity, and photosensitivity.
IEEE SENSORS JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Jun-Hyeong Park, Won Park, Jeong-Hyeon Na, Jinuk Lee, Jun-Su Eun, Junhao Feng, Do-Kyung Kim, Jin-Hyuk Bae
Summary: This study demonstrates high-performance thin-film transistors (TFTs) using atomically thin indium-oxide (InOx) semiconductors fabricated through a solution process. By controlling the solution molarity, the bandgap and thickness of the InOx were tuned to achieve superior field-effect mobility and switching characteristics in TFTs. The optimized InOx TFTs showed high field-effect mobility, high on/off-current ratio, and superior positive and negative gate bias stress stabilities, making them promising for next-generation electronic applications.
Article
Materials Science, Multidisciplinary
Ki Woo Kim, Heesoo Lee, Hyun Jae Kim
Summary: This study proposes a new channel edge doping (CED) technique to reduce the hump effect in LTPS TFTs. By decreasing the electron concentration at the channel edge, the hump characteristic of LTPS TFTs can be effectively reduced. This technique is of great importance for manufacturing active-matrix organic light-emitting diode displays.
JOURNAL OF INFORMATION DISPLAY
(2022)
Article
Nanoscience & Nanotechnology
Ki Seok Kim, Min Seong Kim, Jusung Chung, Dongwoo Kim, I. Sak Lee, Hyun Jae Kim
Summary: We present a transparent and flexible polyimide (PI)-doped single-layer (PSL) phototransistor for visible light detection. By co-sputtering amorphous indium-gallium-zinc oxide (IGZO) and PI targets, the PSL is deposited on a SiO2 gate insulator, serving as both a channel layer and a visible-light absorption layer. The PI doping leads to improved optoelectronic characteristics, including higher photoresponsivity, photosensitivity, and specific detectivity, attributed to the induced subgap states. A flexible PSL phototransistor is also fabricated, demonstrating stable optoelectronic characteristics even after 10,000 bending tests.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Zhangfu Chen, Woohyun Hwang, Minhyun Cho, Anh Tuan Hoang, Minju Kim, Dongwoo Kim, Dong Ha Kim, Young Duck Kim, Hyun Jae Kim, Jong-Hyun Ahn, Aloysius Soon, Heon-Jin Choi
Summary: This study reports on the growth of GeS microribbons via CVT, which exhibit low-symmetry orthorhombic structure and anisotropic optical and electronic properties. The GeS microribbons show photoluminescence and anisotropic absorption effects, making them suitable for photoelectronic transistors.
NPG ASIA MATERIALS
(2022)
Article
Multidisciplinary Sciences
Li Jin Kim, Sujin Jung, Hee Jun Kim, Bong Hwan Kim, Kyung Joon Kwon, Yong Min Ha, Hyun Jae Kim
Summary: In AMOLED displays, the image quality deteriorates when a variable refresh rate is applied and the frame rate changes. We experimentally demonstrated that this phenomenon is dependent on the frequency and can be prevented by applying a variable initial voltage. This approach promises to improve picture quality in AMOLED displays.
SCIENTIFIC REPORTS
(2022)
Article
Materials Science, Multidisciplinary
Kyungho Park, Jin Hyeok Lee, Byung Ha Kang, Jusung Chung, Hee Jun Kim, Kyungmoon Kwak, Hyun Jae Kim
Summary: In this study, IGZO-based phototransistors capable of detection and storage in the visible light region were fabricated through PDMS treatment. The PDMS residues enhance the optoelectronic characteristics of the devices, leading to improved photoresponsivity, photosensitivity, and detectivity. Furthermore, the devices demonstrate potential for multilevel photomemory.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Dongwoo Kim, Won Kyung Min, Hyung Tae Kim, Jusung Chung, Min Seong Kim, Hyun Jae Kim
Summary: This study introduces an amorphous indium-gallium-zinc oxide (IGZO)-based optical synaptic transistor that uses visible light as a signal to show a clear difference between long-term memory (LTM) and short-term memory (STM). By intentionally introducing defects within the IGZO channel layer and inserting mesh-structured titanium dioxide (m-TiO2) layers, the device is enabled to sense visible light, achieving a 110-fold difference between LTM and STM. Additionally, a thin film-structured hafnium dioxide (HfO2) layer is inserted to enhance the persistent photoconductivity (PPC) effect, leading to a prolonged current retention after the light signal is removed.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Gwan In Kim, Joohye Jung, Won Kyung Min, Min Seong Kim, Sujin Jung, Dong Hyun Choi, Jusung Chung, Hyun Jae Kim
Summary: This study proposes a plasma-polymerized hafnium oxide (HfOx) hybrid dielectric to achieve the synergistic advantages of outstanding flexibility in organic dielectrics and remarkable dielectric/insulating properties in inorganic dielectrics. By plasma-polymerizing high-k HfOx with polytetrafluoroethylene (PTFE), a flexible and hydrophobic fluoropolymer dielectric, the PPH-hybrid dielectric exhibits excellent flexibility and maintains a low leakage current density even after repetitive bending stress. The PPH-hybrid dielectric is also applied to amorphous indium-gallium-zinc oxide (IGZO) thin-film transistors (TFTs), demonstrating stable electrical performance and enhanced stability.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Editorial Material
Nanoscience & Nanotechnology
Gerald J. Meyer, Hyun Jae Kim
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Engineering, Electrical & Electronic
Jin Her, Won Kyung Min, Chul Sang Shin, Hoon Jeong, Jeong Ki Park, Hyun Jae Kim
Summary: We developed a new pixel circuit that utilizes dual-gate TFTs to compensate for threshold voltage variations and extend the input data range. Through simulations and experiments, we found that this new pixel circuit performs better in terms of sensing capability and current error rate. It is suitable for high-resolution AMOLED displays and can switch between G-Sync and S-Sync modes as needed.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Nanoscience & Nanotechnology
Kyung Min Kim, Jeong Suk Yang, Hyung Tae Kim, Inhyo Han, Sang-Hoon Jung, Joon-Young Yang, Yong Min Ha, Soo Young Yoon, Hyun Jae Kim
Summary: This study investigates the back-channel interface engineering of oxide thin-film transistors (TFTs) using commercially available silicon oxide (SiOx) and its effects on the electrical characteristics of fully integrated TFTs. The proposed method effectively alleviates back-channel damage, promotes oxygen inter-diffusion, suppresses excess hydrogen inflow, and boosts out-diffusion of residual copper. The result is improved device uniformity and electrical characteristics, including high field effect mobility and significantly suppressed threshold voltage variation with decreasing channel length.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Won Kyung Min, Chihyeong Won, Dong Hyun Kim, Sanghyeon Lee, Jusung Chung, Sungjoon Cho, Taeyoon Lee, Hyun Jae Kim
Summary: A negatively responsive switch-type strain-sensor with twisted conductive fibers is developed that can significantly increase its conductivity from insulating to conducting properties. This sensor can regulate the mutual contact resistance under tensile strain while maintaining exceptional durability. Additionally, three healthcare monitoring systems with near-zero standby power are also developed, expanding the utilization range of fiber strain-sensors.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Jung Chul Kim, I. Sak Lee, Hyung Tae Kim, Jong Bin An, Jae Sung Kim, Juhn Suk Yoo, Han Wook Hwang, Hyun Chul Choi, Yong Min Ha, Hyun Jae Kim
Summary: This paper presents a new pixel circuit and driving scheme for mobile devices with AMOLED displays, utilizing LTPO TFTs. The proposed circuit and scheme ensure uniform luminance and eliminate flickering at various refresh rates. Experimental results demonstrate that extending the compensation time and applying a higher voltage to the D-TFTs effectively improve luminance uniformity and reduce flicker. A 6.0-inch QHD LTPO-based AMOLED display was successfully fabricated using this approach.
JOURNAL OF INFORMATION DISPLAY
(2023)
Editorial Material
Engineering, Electrical & Electronic
Hyun Jae Kim, Kirk Schanze, Chengmei Zhong
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Bogyeom Seo, Jusung Chung, Naresh Eedugurala, Jason D. Azoulay, Hyun Jae Kim, Tse Nga Ng
Summary: This study demonstrates the integration of an organic bulk heterojunction polymer layer on an oxide thin-film transistor to achieve high-efficiency photodetection in the short-wave infrared region. By using trap-assisted charge injection, the organic semiconductor's photoresponse at longer wavelengths is enhanced. The detector performance is optimized by investigating the balance between bias stress and signal-to-noise under different bias conditions, resulting in a responsivity at 1550 nm up to 130 mA/W at a low light intensity.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Seung Hee Kang, I. Sak Lee, Kyungmoon Kwak, Kyeong Take Min, Nack Bong Choi, Han Wook Hwang, Hyun Chul Choi, Hyun Jae Kim
Summary: The effect of boron (B) implantation into the source/drain region of a self-aligned coplanar amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistor (TFT) on the electrical properties and device stability was investigated. The results showed that the electrical properties were optimized when the projection range of B was in the central vertical region of the film. B implantation decreased resistivity and improved field-effect mobility, and the fabricated TFTs exhibited excellent stability.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
