High-performance and operationally stable organic thin-film transistors using bi-buffer layers with low-cost electrodes

We report a copper (Cu)-based source/drain (S/D) electrodes organic thin-film transistor (OTFT) with bi-buffer layer structure consisting of firstly a CuOx layer and secondly MoO3 layer. Comparing with single Cu s/d electrodes OTFTs, bi-buffer layer devices not only exhibit enhanced mobilities by more than five times, but also show an improvement of operation stability. The performance enhancement is attributed to improvement of interfacial properties between organic active layer and Cu s/d electrodes, which was analysed by x-ray photoelectron spectroscopy and contact resistance. (paper)