High-Photoresponsivity Transistors Based on Small-Molecule Organic Semiconductors

We investigate the viability of 2,8-difluoro-5,11-bis(triethylsilylethynyl)anthradithiophene (diF-TES ADT) as a photosensor and show that there is a direct correlation between the absorption spectrum of the material and the magnitude of the resulting drain current in a field-effect transistor device made from it. We show that the diF-TES ADT device exhibits very high photosensitivity and photoresponsivity for green and blue light. We also propose a hybrid device structure that leverages the high absorptivities of two organic semiconductors to make a sandwich device with high phototransistor metrics across all wavelengths of visible light.