Normally-off GaN HEMTs with InGaN p-gate cap layer formed by polarization doping. (17th December 2021)

• Record Type: Journal Article
• Authors: Zeng, Changkun; Xu, Weizong; Xia, Yuanyang; Wang, Ke; Ren, Fangfang; Zhou, Dong; Li, Yiheng; Zhu, Tinggang; Chen, Dunjun; Zhang, Rong; Zheng, Youdou; Lu, Hai
• Is Part Of: Applied physics express. Volume 15:Number 1(2022)
• Publication Date: 2021-12-17
• Subjects: polarization doping -- InGaN p-gate cap layer -- normally-off GaN HEMT -- Schottky-type gate contact -- gate swing range; Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.35848/1882-0786/ac407e
• Languages: English
• ISSNs: 1882-0778

Abstract

Abstract: Narrow gate margin has been the critical limiting factor for the p-gate normally-off GaN HEMTs, imposing significant challenges in both gate drive design and gate reliability. In this work, by developing dopant-free p-type polarization doping technique in composition-graded InGaN layer, high-quality Schottky contact between the gate metal and cap layer was demonstrated, achieving excellent gate current blocking performance (10 –6 mA mm −1 ) after the turning-on of the gate heterojunction structure. Resultantly, normally-off GaN HEMTs with enhanced gate breakdown voltage up to 15.2 V was realized, being especially beneficial for the simplification of gate drive design and the safe operation of gate terminal.