1. Department of Materials Science and Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Republic of Korea
2. Department of Electrical, Computer, and Systems Engineering, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, New York 12180, United States
3. School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center, Chonbuk National University, Jeonju 54896, Republic of Korea