1. Division of Electronics and Electrical Engineering, Dongguk University 1 , Seoul 04620, Republic of Korea
2. Semiconductor Devices and Circuits Laboratory, Advanced Institute of Convergence Technology (AICT), Seoul National University 2 , 145, Gwanggyo-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16229, Republic of Korea