Improvement of On/Off Ratio in Organic Field-effect Transistor Having Thin Molybdenum Trioxide Layer. - Masahiro Minagawa; Hidetsugu Tamura; Ryo Sakikawa; Itsuki Ikarashi; Akira Baba; Kazunari Shinbo; Keizo Kato; Futao Kaneko (IEICE Trans. Electron., 2015)