Photoconductive behaviors of difluorinated 5,11-bis(triethylsilylethynyl) anthradithiophene

Abstract In this report, we demonstrate a photoconductive device based on difluorinated 5,11-bis(triethylsilylethynyl) anthradithiophene (diF-TES-ADT). The light intensity dependences of the transient photocurrent combined with theoretical analyses clearly show that a simple device architecture consisting of diF-TES-ADT and two Au electrodes patterned in parallel forms an efficient, trap-limited, gain-generating photoconductive device, resulting in high responsivity up to approximately 500 A/W. Moreover, the efficient gain-generating nature of diF-TES-ADT enables efficient tuning of the charge carrier density in the channel region, resulting in unprecedentedly sensitive phototransistor performance with high current modulation exceeding 106 as well as hysteresis-free threshold voltage shifts.