Light-Exposure Effects on Electrical Characteristics of 6,13-Bis(triisopropylsilylethynyl)Pentacene/CdTe Composite Thin-Film Transistors

We report the light-exposure effects on solution-processed organic thin-film transistors (TFTs) based on a 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) semiconductor. Under light exposure, the increase in drain current and the positive shift of threshold voltage are observed, which are more remarkable for the TIPS-pentacene/cadmium telluride composite TFT. Herein the photosensitivity in these TFTs is explained in terms of photovoltaic and photoconductive effects. Composite semiconductors blended with sensitizers are suggested to enhance the quantum efficiency of organic phototransistors. (C) 2013 The Japan Society of Applied Physics