1. Department of Electrical Engineering, National Cheng Kung University, Tainan 70101, Taiwan
2. Graduate Institute of Opto-Mechatronics Engineering, National Chung Cheng University, Min-Hsiung 62102, Chiayi, Taiwan
3. Department of Electrophysics, National Chiayi University, Chiayi 60004, Taiwan
4. Institute of Microelectronics, National Cheng Kung University, Tainan 70101, Taiwan
5. Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan 70101, Taiwan
6. Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan