1. Department of MicroelectronicsUniversity of Chinese Academy of SciencesBeijing100029People's Republic of China
2. Institute of Microelectronics Chinese Academy of SciencesBeijing100029People's Republic of China
3. Kunshan BranchInstitute of Microelectronics Chinese Academy of SciencesKunshanJiangsu215347People's Republic of China
4. National Center for Nanoscience and TechnologyBeijing100190People's Republic of China