1. Department of Organic Device Engineering; Research Center for Organic Electronics; Yamagata University; 4-3-16 Jonan Yonezawa, Yamagata 992-8510 Japan
2. Department of Polymer Science and Engineering; Yamagata University; 4-3-16 Jonan Yonezawa, Yamagata 992-8510 Japan
3. Institute of Material Structure Science; High Energy Accelerator Research Organization (KEK); 203-1 Shirakata Tokai Naka 319-1106 Japan