1. Center for Electronic Materials, Korea Institute of Science and Technology (KIST), 5, Hwarang-ro 14 gil, Seongbuk-gu, Seoul 02792, Republic of Korea
2. Division of Nano & Information Technology, KIST School, University of Science and Technology (UST), 217, Gajeong-ro, Yuseong-gu, Daejeon 34113, Republic of Korea
3. Center for Opto-Electronic Materials and Devices, Korea Institute of Science and Technology (KIST), 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea