High Performance Crystalline Organic Transistors and Circuit

Abstract

Abstract : We have examined the best available small molecule crystalline organic semiconductors as active layers in thin-film transistors. We have optimized the field-induced conductance, a figure of merit that will relate directly to circuit speeds. A simple figure of merit - the product of the field-effect mobility and effective relative dielectric constant of the gate insulator (or mobility times the product of capacitance per unit area and total insulator thickness for bilayers) has been used to compare our devices with all the published work in the literature up until the project ending. The best semiconductor-insulator combination was found to a porphryn semiconductor in conjunction with a bilayer gate insulator consisting of ~ 100 nm Ta2O3 and 2.3 nm SiO2. We also discuss the physics of charge trapping at various semiconductor-dielectric interfaces.