1. Institute of Photoelectronic Thin Film Devices and Technology and Tianjin Key Laboratory of Thin Film Devices and Technology, Nankai University, Tianjin 300071, P.R. China
2. Guang Dong Hanergy Thin-film Solar Co., Ltd., Guang Dong 517500, P.R.China
3. Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong, Institute for Advanced Interdisciplinary Research (iAIR), University of Jinan, Shandong, Jinan 250022, China