Charge Injection in Regioregular Poly-(3-Hexythiophene) Organic Field-Effect Transistors with Different Metal Electrodes

Here we report on regioregular poly-(3-hexythiophene) (P3HT) organic field-effect transistors (OFETs) with various metal electrodes: pristine Au, pristine Cr, and Cr/Au. Compared to the performance of OFETs using different electrodes, the OFETs with Au electrode have better mobility (μ = 0.0090 cm2/Vs) and larger current at the same source-drain voltage and gate voltage. The enhancement of the device performance with Au electrode can be attributed to a small contact resistance and a small barrier height to P3HT for hole carrier injection.