Understanding the metal-oxides induced reduction of the contact resistance in organic transistors

Abstract It is well known that inserting metal oxides on top of electrodes in coplanar bottom-gate bottom-contact organic field-effect transistors (OFETs) improves the OFET performance in terms of increased current density, higher effective mobility and reduced contact resistance. This work elucidates the transistor performance gain in case of oxidized metal electrodes using numerical device simulations and experimental data. The study strongly supports the hypothesis that the impact of oxidization can be explained for these experiments by an improvement of the semiconductor morphology in the vicinity of oxidized electrodes in conjunction with an improved mobility in these regions.