1. Institute of MicroelectronicsPeking UniversityBeijingPeople's Republic of China
2. Key Laboratory of Nanodevices and ApplicationsSuzhou Institute of Nano‐tech and Nano‐bionics, Chinese Academy of SciencesJiangsu SuzhouPeople's Republic of China
3. Key Laboratory of Ministry of Education for Wide Band‐Gap Semiconductor Materials and DevicesMicroelectronics Institute, Xidian UniversityXi'an710071People's Republic of China