A temperature dependent power-law drain current model for coplanar OFETs

Abstract

We present a drain current model for coplanar organic field-effect transistors (OFETs) considering temperature dependent power-law mobility and contact resistance. By solving a microscopic two-dimensional equivalent circuit model, we demonstrate that the power-law dependence of mobility on the gate voltage leads to the asymptotic power-law dependence of the contact resistance. Furthermore, we validated the model by measuring the transfer characteristics of pentacene-based coplanar OFETs in a wide temperature range between 293 K and 373 K. We study the temperature dependence of the characteristic temperature on the power-law exponent and the on-state resistance. We showed that the characteristic temperature is independent of the temperature and the on-state resistance follows an inverse Arrhenius-type law.