1. KeyLab of Semiconductor Materials Science, Institute of Semiconductors; Chinese Academy of Sciences; Beijing P.R. China
2. School of Electronic Engineering; Xi'an University of Posts and Telecommunications; Xi'an P.R. China
3. Beijing Huajin Chuangwei Technology Co., Ltd.; Beijing P.R. China
4. Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices; Beijing P.R. China