Evaluation of stress voltage on off-state time-dependent breakdown for GaN MIS-HEMT with SiNx gate d

• 作 者: Tao-Tao Que Ya-Wen Zhao Qiu-Ling Qiu Liu-An Li Liang He Jin-Wei Zhang Chen-Liang Feng Zhen-Xing Liu Qian-Shu Wu Jia Chen Cheng-Lang Li Qi Zhang Yun-Liang Rao Zhi-Yuan He Yang Liu
• 机 构: School of Electronics and Information Technology, Sun Yat-Sen University, Guangzhou 510275, China;Sc
• 出 处: 中国物理B（英文版）
• 发表日期: 2020年10期
• 关键词: gallium nitride LPCVD-SiNx MIS-HEMT time-dependent breakdown negative gate bias

Stress voltages on time-dependent breakdown characteristics of GaN MIS-HEMTs during negative gate bias stress (with VGS < 0, VD = VS = 0) and off-state stress (VG 0, VS = 0) are investigated. For negative bias stress, the breakdown time distribution (β) decreases with the increasing negative gate voltage, while β is larger for higher drain voltage at off-state stress. Two humps in the time-dependent gate leakage occurred under both breakdown conditions, which can be ascribed to the dielectric breakdown triggered earlier and followed by the GaN layer breakdown. Combining the electric distribution from simulation and long-term monitoring of electric parameter, the peak electric fields under the gate edges at source and drain sides are confirmed as the main formation locations for per-location paths during negative gate voltage stress and off-state stress, respectively.