Organic field-effect transistors with nearly non-injection barrier from source/drain electrodes to pentacene

Top contact pentacene field-effect transistors (OFETs) with or without MoO3 source/drain (S/D) electrodes buffer layers were fabricated by utilizing different deposition rates of Au S/D electrodes. The results showed that the characteristics of these OFETs have a strong dependence on the deposition rate of Au S/D electrodes. More importantly, single pentacene layer OFETs with optimized Au deposition process exhibits significantly improved performance, which is almost equal to the OFETs with MoO3 buffer layers. The high performance of OFETs with optimized Au deposition process was attributed to an improved contact of Au and pentacene caused by ordered dipole arrangement at the interface, leading to a nearly non-injection barrier of charge carriers from Au electrodes to pentacene.