Low Leakage Current and High Breakdown Field AlGaN/GaN MIS-HEMTs Using PECVD-SiN<i>x</i> as a Gate Dielectric
Xiaohui Gao,
Hui Guo,
Rui Wang,
Danfeng Pan,
Peng Chen,
Dunjun Chen,
Hai Lu,
Rong Zhang,
Youdou Zheng
Affiliations
Xiaohui Gao
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
Hui Guo
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
Rui Wang
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
Danfeng Pan
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
Peng Chen
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
Dunjun Chen
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
Hai Lu
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
Rong Zhang
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
Youdou Zheng
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
In this paper, SiNx film deposited by plasma-enhanced chemical vapor deposition was employed as a gate dielectric of AlGaN/GaN high electron mobility transistors (HEMTs). We found that the NH3 flow during the deposition of SiNx can significantly affect the performances of metal–insulator–semiconductor (MIS) HEMTs. Compared to that without using NH3 flow, the device with the optimized NH3 flow exhibited three orders of magnitude lower gate leakage current, two orders of magnitude higher ON/OF drain current ratio, and an increased breakdown field by 69%. In addition, an in situ N2 plasma surface treatment prepared prior to SiNx deposition can further improve DC performances of MIS-HEMTs to a very low gate leakage current of 10−9 mA/mm and a high ON/OFF drain current ratio up to 109 by reducing the interface state density. These results demonstrate the great potential for using PECVD-SiNx as a gate dielectric in GaN-based MIS-HEMTs.