Article
Chemistry, Analytical
Idriss Abid, Youssef Hamdaoui, Jash Mehta, Joff Derluyn, Farid Medjdoub
Summary: We report on the fabrication and electrical characterization of AlGaN/GaN normally off transistors on silicon designed for high-voltage operation. The normally off configuration was achieved with a p-gallium nitride (p-GaN) cap layer below the gate, enabling a positive threshold voltage higher than +1 V. The buffer structure was based on AlN/GaN superlattices (SLs), delivering a vertical breakdown voltage close to 1.5 kV with a low leakage current all the way to 1200 V.
Article
Computer Science, Information Systems
Wei Lin, Maojun Wang, Haozhe Sun, Bing Xie, Cheng P. Wen, Yilong Hao, Bo Shen
Summary: This paper proposes an HEMT structure with a source-connected p-GaN embedded in a carbon-doped semi-insulating buffer to suppress the buffer-induced current collapse effect. Two-dimensional transient simulation demonstrates the successful suppression of current collapse in SCPG-HEMTs compared to conventional HEMTs. The mechanism of ejecting holes from SCPG into the high resistive buffer layer after off-state stress is illustrated to potentially solve the buffer-induced degradation of dynamic on-resistance in GaN power devices.
Article
Physics, Applied
Ajay Shanbhag, Ramdas P. Khade, Sujan Sarkar, M. P. Sruthi, Deleep Nair, Anjan Chakravorty, Nandita DasGupta, Amitava DasGupta
Summary: An accurate method for extracting the thermal resistance of GaN-on-Si HEMTs is proposed in this paper. By pulsing the substrate instead of the drain or gate, the impact of traps on the extraction process is reduced. Experimental results show the effectiveness of the proposed method compared to the existing drain pulsing method.
APPLIED PHYSICS LETTERS
(2023)
Article
Computer Science, Information Systems
Ran Ye, Xiaolong Cai, Chenglin Du, Haijun Liu, Yu Zhang, Xiangyang Duan, Jiejie Zhu
Summary: This paper summarizes the investigations of trapping effects and discusses methods to suppress them in AlGaN/GaN HEMTs. Understanding the inner mechanism and comparing different methods can improve the device performance.
Article
Engineering, Electrical & Electronic
Yuji Ando, Ryutaro Makisako, Hidemasa Takahashi, Akio Wakejima, Jun Suda
Summary: The study revealed that the epitaxial layer structure affects the electrical characteristics of AlGaN/GaN HEMTs. GaN-on-GaN HEMTs showed an improved tradeoff between maximum drain current and breakdown characteristics compared to GaN-on-SiC HEMTs. Moreover, the impact of Fe diffusion on frequency dispersion was relatively limited in GaN-on-GaN devices.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Ankit Soni, Mayank Shrivastava
Summary: This study investigated the impact of various charge sources on the electric field distribution and breakdown mechanism of HEMTs, revealing strong correlations between different charges and breakdown voltage. Insights were developed to explain the dependence of HEMT breakdown on surface states, polarization charge, and buffer traps, aiding in the design of efficient surface passivation schemes.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Physics, Applied
Chih-Yao Chang, Yao-Luen Shen, Shun-Wei Tang, Tian-Li Wu, Wei-Hung Kuo, Suh-Fang Lin, Yuh-Renn Wu, Chih-Fang Huang
Summary: In this study, a novel etching buffer layer was designed and incorporated into the p-GaN/AlGaN/GaN high electron mobility transistor structure to improve the etching process. The results showed that the device with the buffer layer exhibited improved process uniformity and device performance.
APPLIED PHYSICS EXPRESS
(2022)
Article
Physics, Applied
Xin Chen, Yaozong Zhong, Shumeng Yan, Xiaolu Guo, Hongwei Gao, Xiujian Sun, Haodong Wang, Fangqing Li, Yu Zhou, Meixin Feng, Ercan Yilmaz, Qian Sun, Hui Yang
Summary: The characteristics of an AlGaN/GaN high-electron-mobility transistor buffer structure are studied and optimized by employing an AlN/GaN superlattice (SL) structure. The influence of buffer traps on carrier transport behaviors and electrical performance for SL buffer structures under a high electric field is analyzed. The AlN/GaN SL buffer structures are further optimized with various AlN/GaN thickness ratios and their total thickness, achieving a high breakdown voltage and suppressing the buffer trapping effect.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Yan Wang, Wenhao Zheng, Shuman Mao, Bo Yan, Qingzhi Wu, Yuehang Xu
Summary: This study investigates the degradation of flexible AlGaN/GaN HEMTs under bending tensile strain for the first time. The traps locations were identified and characterized, and the results have important implications for further application of GaN technology in flexible electronics.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Materials Science, Multidisciplinary
Yijun Dai, Zihui Zhao, Tian Luo, Zhehan Yu, Li Chen, Wei Guo, Jichun Ye
Summary: This article demonstrates the polarization-induced self-isolation in AlGaN/GaN high-electron-mobility transistors (HEMTs) through the incorporation of lateral-polarity structures (LPS). The incorporation of LPS leads to the formation of a 2D electron gas (2DEG) in the III-polar heterojunction and depletion in the N-polar counterpart. The introduction of LPS provides a novel planar isolation technique with improved device performance by eliminating the isolation leakage path.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Nicola Modolo, Carlo De Santi, Andrea Minetto, Luca Sayadi, Sebastien Sicre, Gerhard Prechtl, Gaudenzio Meneghesso, Enrico Zanoni, Matteo Meneghini
Summary: The goal of this study is to investigate the impact of hard switching on the dynamic performance of GaN HEMTs. By developing a fast testing system, the researchers found that optimizing the drain node capacitance can accelerate the hard-switching transition. Through experiments at multiple frequencies, it was demonstrated that cumulative turn-on stress has a stronger effect on R-ON compared to off-state stress. By comparing devices with different LCDs, hot electrons were identified as the main mechanism in device degradation. Furthermore, comparing wafers with different processing conditions revealed the significant impact of buffer properties on the dynamic performance of devices in hard switching.
IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Oguz Odabasi, Amir Ghobadi, Turkan Gamze Ulusoy Ghobadi, Bayram Butun, Ekmel Ozbay
Summary: This study investigates the impact of trapping and fluorine (F) inclusion on the operation of AlGaN/GaN high electron mobility transistors (HEMTs) through structural and electrical analyses. The results show that the SiNx interfacial layer reduces defect formation, while the pre-gate annealing (PGA) process mitigates the virtual gate phenomenon, leading to stable operation with minimized lag performance.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Engineering, Electrical & Electronic
M. Florovic, J. Kovac, A. Chvala, J. -c. Jacquet, S. L. Delage
Summary: In this article, pinch-off voltage biasing was used for the first time to determine the average channel temperature of the AlGaN/GaN HEMT, excluding the device's electrical parameters dependence in the linear operating mode. The theoretical part focused on the thermal model with temperature-dependent thermal resistance to determine the average temperature of the HEMT under quasi-static operation. The experimental part discussed the appropriate methods for determining the active area average temperature using constant isothermal saturation current or short-pulse current.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Chemistry, Analytical
Yu-Lin Song, Manoj Kumar Reddy, Luh-Maan Chang, Gene Sheu
Summary: This study presents an analysis of the physics-based TCAD simulation procedure for GaN/AlGaN/GaN HEMT device structures grown on Si (111) substrate, calibrated against measurement data. The study investigates the impact of traps on device performance and the complexity of identifying their source and position in the device. The research focuses on key parameters for tuning threshold voltage in GaN transistors and demonstrates good agreement with experimental data.
Article
Materials Science, Multidisciplinary
Zixin Zhen, Quan Wang, Yanbin Qin, Changxi Chen, Jiankai Xu, Lijuan Jiang, Hongling Xiao, Qian Wang, Xiaoliang Wang, Manqing Tan, Chun Feng
Summary: This article proposes a metal-insulator-semiconductor high-electron-mobility transistor (MIS-HEMT) with Al2O3/SiN x double insulators to achieve lower gate leakage and lower current collapse simultaneously. The proposed structure exhibits superior performance in terms of gate leakage, current collapse, and overall device performance. Additionally, the proposed structure has low requirements on fabrication techniques and induces fewer interface traps.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2022)
Editorial Material
Engineering, Electrical & Electronic
Jesus A. Del Alamo
IEEE ELECTRON DEVICE LETTERS
(2020)
Article
Multidisciplinary Sciences
Xiahui Yao, Konstantin Klyukin, Wenjie Lu, Murat Onen, Seungchan Ryu, Dongha Kim, Nicolas Emond, Iradwikanari Waluyo, Adrian Hunt, Jesus A. del Alamo, Ju Li, Bilge Yildiz
NATURE COMMUNICATIONS
(2020)
Article
Engineering, Electrical & Electronic
Alon Vardi, Moshe Tordjman, Rafi Kalish, Jesus A. del Alamo
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2020)
Editorial Material
Engineering, Electrical & Electronic
Jesus A. del Alamo
IEEE ELECTRON DEVICE LETTERS
(2020)
Editorial Material
Engineering, Electrical & Electronic
Jesus A. Del Alamo
IEEE ELECTRON DEVICE LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Yanjie Shao, Marco Pala, David Esseni, Jesus A. del Alamo
Summary: This study investigates the diameter scaling behavior of broken-band GaSb/InAs vertical nanowire Esaki diodes, and finds a great potential for ultra-low power applications. The research includes fabrication and characterization of devices, as well as modeling and simulations.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Dongsung Choi, Alon Vardi, Jesus A. del Alamo
Summary: A novel test structure for studying sidewall ohmic contacts to III-V fins for FinFETs was presented. The impact of digital etch and thermal annealing on the contact resistivity of Mo/n(+)-InGaAs fin sidewall contacts was characterized. Thermal annealing was found to significantly improve the sidewall contact resistivity, demonstrating the importance of understanding sidewall ohmic contact formation for future high-performance InGaAs FinFETs.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Engineering, Electrical & Electronic
Dimitri Antoniadis, Taekyong Kim, Jesus A. del Alamo
Summary: The nucleation-limited switching (NLS) model has been successful in explaining the dynamics of polarization switching in polycrystalline ferroelectric films in various experiments, but its mathematical complexity has hindered its implementation in realistic circuit simulations with complex driving waveforms. By reformulating NLS as a generalized polarization rate equation, researchers have been able to capture nucleation incubation time and intra- and inter-grain switching statistics accurately, paving the way for efficient numerical finite-difference computation and verification in circuit simulations.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Physics, Applied
Ethan S. Lee, Jungwoo Joh, Dong Seup Lee, Jesus A. del Alamo
Summary: In this study, the impact of gate geometry on forward operation of Schottky-gate p-GaN high electron mobility transistors (HEMTs) was experimentally investigated. The results showed that gate geometry affected the threshold voltage and subthreshold swing scaling, but had a classical scaling effect on peak transconductance and ON resistance. Additionally, the relative areas of two junctions in Schottky-type p-GaN gate HEMTs were found to be an additional design degree of freedom to fine-tune device performance.
APPLIED PHYSICS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Yanjie Shao, Jesus A. del Alamo
Summary: In this letter, we present the achievement of sub-10-nm diameter vertical nanowire p-type tunnel FETs. By utilizing a broken-band GaSb/InAsSb heterostructure design and a top-down fabrication approach, we successfully demonstrate a 9-nm diameter VNW TFET with excellent performance, indicating the potential viability of GaSb-based complementary TFETs in future ultra-scaled logic technologies.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Alon Vardi, Moshe Tordjman, Rafi Kalish, Jesus A. del Alamo
Summary: The impact of WO3 passivation on the electrical characteristics of hydrogen-terminated diamond MOSFETs with WC edge contacts is studied. WO3 is found to significantly improve both contact and extrinsic channel sheet resistance, enabling fast device turn-off.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Taekyong Kim, Jesus A. del Alamo, Dimitri A. Antoniadis
Summary: The existence of negative capacitance (NC) and the switching dynamics of ferroelectric HfZrO2 (FE-HZO) metal-ferroelectric-Metal (MFM) structures are still contentious and unclear. This work provides a detailed study of the switching characteristics of HZO MFM structures and demonstrates that there is no evidence of NC effect. The study emphasizes the crucial role of parasitics in the dynamic characterization of R-MFM circuits.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Multidisciplinary Sciences
Murat Onen, Nicolas Emond, Baoming Wang, Difei Zhang, Frances M. Ross, Ju Li, Bilge Yildiz, Jesus A. del Alamo
Summary: In this study, highly desirable silicon-compatible nanoscale protonic programmable resistors were developed, enabling efficient and fast proton shuttling and intercalation at room temperature under extreme electric fields. The devices exhibited symmetric, linear, and reversible modulation characteristics, surpassing the space-time-energy performance of biological synapses.
Biographical-Item
Engineering, Electrical & Electronic
Jesus A. del Alamo
Summary: The article welcomes Prof. Elaheh Ahmadi to the Editorial Board of IEEE Electron Device Letters, with her subject area being Compound Semiconductor Devices.
IEEE ELECTRON DEVICE LETTERS
(2022)
Editorial Material
Engineering, Electrical & Electronic
Jesus A. del Alamo
Summary: Prof. Min Hyuk Park has joined the Editorial Board of IEEE Electron Device Letters and his research areas include Emerging Technologies and Devices and Memory Devices and Technology.
IEEE ELECTRON DEVICE LETTERS
(2022)