[1] Sungkyunkwan Univ SKKU, Sch Adv Mat Sci & Engn, SKKU Adv Inst Nanotechnol, Suwon 440746, South Korea
[2] Seoul Natl Univ, Program Nano Sci & Technol, Grad Sch Convergence Sci & Technol, Seoul 151744, South Korea
[3] Korea Inst Sci & Technol, Ctr Elect Mat, Seoul 136791, South Korea
[4] Adv Inst Convergence Technol, Suwon 443270, Gyeonggi Do, South Korea