1 School of Electronic Science and Engineering (National Model Microelectronics College), Xiamen University, Xiamen 361005, China
2 Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen 361005, China
3 Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility, Clayton 3168, VIC, Australia
4 Institute of Materials Research and Engineering, Agency for Science, Technology, and Research (A*STAR) 2 Fusionopolis Way, Innovis 08-03, Singapore 138632, Singapore
5 School of Engineering, RMIT University, Melbourne, Victoria 3001, Australia