1. Institute of Physics and Applied Physics; Yonsei University; Seoul 120-749 Republic of Korea
2. Department of Chemistry; Hanyang University; 17 Haengdang-Dong Sungdong-Ku Seoul 133-791 Korea
3. Samsung Display Co., Ltd; #95, Samsung 2-ro Giheung-gu Yongin-si Gyeonggi-do 446-711 Korea