Zhang Haitao, Kang Xuanwu, Zheng Yingkui, Wei Ke, Wu Hao, Liu Xinyu, Ye Tianchun, Jin Zhi
High-Frequency High-Voltage Device and Integrated Circuits Center, Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China.
School of Electronic Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.
Micromachines (Basel). 2022 May 9;13(5):748. doi: 10.3390/mi13050748.
In this study, a dedicated dynamic measurement system was used to investigate the transient capacitance and recovery process of AlGaN/GaN lateral Schottky barrier diodes (SBDs). With the consideration of acceptor traps in the C-doped buffer, the C-V characteristics and transient capacitance were measured and analyzed, and the results were simulated and explained by Silvaco TCAD (technology computer aided design). The ionization of acceptor traps and the change of electric potential were monitored in transient simulation to investigate the origin of the capacitance collapse in the SBD. The results suggest the significant impact of traps in the GaN buffer layer on the capacitance collapse of the device, and the secondary capture effect on the variation of acceptor ionization. Based on the study of transient capacitance of SBD, this work could be extended to the Miller capacitance in high electron mobility transistor (HEMT) devices. Moreover, the report on the stability of capacitance is essential for GaN devices, and could be further extended to other aspects of device research.
在本研究中，使用了专门的动态测量系统来研究AlGaN/GaN横向肖特基势垒二极管（SBD）的瞬态电容和恢复过程。考虑到C掺杂缓冲层中的受主陷阱，测量并分析了其C-V特性和瞬态电容，并通过Silvaco TCAD（技术计算机辅助设计）对结果进行了模拟和解释。在瞬态模拟中监测受主陷阱的电离和电势变化，以研究SBD中电容崩塌的起源。结果表明，GaN缓冲层中的陷阱对器件的电容崩塌有显著影响，以及对受主电离变化的二次俘获效应。基于对SBD瞬态电容的研究，这项工作可扩展到高电子迁移率晶体管（HEMT）器件中的米勒电容。此外，关于电容稳定性的报告对GaN器件至关重要，并且可以进一步扩展到器件研究的其他方面。
