1. Department of Precision InstrumentTsinghua University Beijing 100084 P. R. China
2. ZNDY of Ministerial Key LaboratorySchool of Mechanical EngineeringNanjing University of Science and Technology Nanjing Jiangsu 210094 P. R. China
3. Beijing Institute of Nanoenergy and NanosystemsChinese Academy of Sciences Beijing 100083 P. R. China
4. School of Materials Science and EngineeringSun Yat‐sen University Guangzhou Guangdong 510275 P. R. China
5. Beijing Innovation Center for Future ChipsTsinghua University Beijing 100084 P. R. China
6. Center for Flexible Electronics TechnologyTsinghua University Beijing 100084 P. R. China
7. School of Instrument Science and Opto‐Electronic EngineeringBeijing Information Science and Technology University Beijing 100192 P. R. China