1. Department of Electronic Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807618, Taiwan
2. Institute of Photonics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807618, Taiwan
3. Taiwan Semiconductor Research Institute, Hsinchu 300091, Taiwan
4. Department of Electronic Engineering, National United University, Miaoli 360001, Taiwan