1. Shanghai Jiao Tong University,National Key Laboratory of Advanced Micro and Nano Manufacture Technology,Shanghai,China,200240
2. School of Integrated Circuits, Peking University,Beijing,China,100871
3. Institute of Semiconductors, Chinese Academy of Sciences,State Key Laboratory of Superlattices and Microstructures,Beijing,China,100083
4. Changxin Memory Technologies, Inc.,HeFei,China,230088