1. Department of Electrical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang-si, Gyeongsangbuk-do 37673, South Korea
2. Advanced Materials Division, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, South Korea
3. Semiconductor R&D Center, Samsung Electronics, 1 Samsungjeonja-ro, Hwaseong-si, Gyeonggi-do 18448, South Korea