High-Performance Bottom-Contact Organic Thin-Film Transistors with Controlled Molecule-Crystal/Electrode Interface

摘要

Organic thin-film transistors (OTFTs) are emerging as an inexpensive alternative to amorphous silicon devices because of their many attractive features, such as a simple fabrication process, low cost, and mechanical flexibility. Recently, the performance of OTFTs has been significantly improved by modifying the dielectric surface and/or source and drain (S/D) electrodes, or by using novel dielectric materials. However, high-performance OTFTs were mostly achieved in top-contact (TC) configurations and not in bottom-contact (BC) configurations. As organic active materials are sensitive to chemical wet and ion-beam processes, shadow-mask evaporation is usually used to form S/D electrodes in TC configurations. Such a process, however, is incompatible with large-scale integration and does not allow one to produce a channel length shorter than a few tens of micrometers. It is therefore desirable to use a BC configuration, which is compatible with fine lithography processing, for promising applications such as high-resolution flexible displays.