1. Department of Materials Science and Engineering; Korea University; 1-5 Ga, Anam-dong Seong buk-gu Seoul 136-701 Korea
2. Department of Information Technology-Nano Science; KU-KIST Graduate School of Converging Science and Technology; Korea University; 1-5 Ga, Anam-dong Seongbuk-gu Seoul 136-701 Korea
3. Department of Digital Display Engineering; Hoseo University; 20, Hoseo-ro 79beon-gil Baebang-eup Asan-si Chungcheongnam-do 31499 Korea