1. Department of Physics and Electronics; Osaka Prefecture University; Sakai 599-8531 Japan
2. The Research Institute for Molecular Electronic Devices, Osaka Prefecture University; Sakai 599-8531 Japan
3. Citizen Holdings Co., Ltd.; Tokorozawa Saitama 359-8511 Japan
4. Kyoto Research Center, Fuso Chemical Co., Ltd.; Fukuchiyama Kyoto 620-0853 Japan
5. Department of Electronic Materials; Osaka Municipal Technical Research Institute; Osaka 536-8533 Japan