TITLE:
Investigation on Breakdown Characteristics of Various Surface Terminal Structures for GaN-Based Vertical P-i-N Diodes
AUTHORS:
Song Shi, Guanyu Wang, Yingcong Xiang, Chuan Guo, Xing Wang, Yinlin Pu, Huilan Li, Zhixian Li
KEYWORDS:
GaN, P-i-N, Mesa Edge Terminal, Electric Field Crowding
JOURNAL NAME:
Journal of Applied Mathematics and Physics,
Vol.12 No.2,
February
29,
2024
ABSTRACT: GaN-based vertical P-i-N diode with mesa edge terminal structure due to electric field crowding effect, the breakdown voltage of the device is significantly reduced. This work investigates three terminal structures, including deeply etched, bevel, and stepped-mesas terminal structures, to suppress electric field crowding effects at the device and junction edges. Deeply-etched mesa terminal yields a breakdown voltage of 1205 V, i.e., 89% of the ideal voltage. The bevel-mesa terminal achieves about 89% of the ideal breakdown voltage, while the step-mesa terminal is less effective in mitigating electric field crowding, at about 32% of the ideal voltage. This work can provide an important reference for the design of high-power, high-voltage GaN-based P-i-N power devices, finding a terminal protection structure suitable for GaNPiN diodes to further enhance the breakdown performance of the device and to unleash the full potential of GaN semiconductor materials.