1. Center for Solar Energy materials Advanced Materials Division; Korea Research Institute of Chemical Technology (KRICT); 141 Gajeong-Ro Yuseong-Gu Daejeon 305-600 Republic of Korea
2. Department of Materials Science and Engineering and Inter-University Semiconductor Research Center; Seoul National University; Seoul 151-744 Republic of Korea
3. Department of Energy Science; Sungkyunkwan University; 2066 Seobu-Ro Jangsan-Gu Suwon 440-746 Republic of Korea