Maxwell–Wagner Model Analysis for the Capacitance–Voltage Characteristics of Pentacene Field Effect Transistor

Abstract

The current–voltage (I–V) and capacitance–voltage (C–V) characteristics of pentacene field effect transistors (FETs) were examined to clarify channel formation in conjunction with the UV/ozone treatment of the source and drain metal (Au) electrodes. Analyzing the I–V and C–V characteristics of FETs using the Maxwell–Wagner model showed that the main charge carriers in the FET channel are holes injected from the source, and that a pentacene FET with a UV/ozone-treated substrate shows a high effective mobility owing to holes smoothly injected into the FET channel. Furthermore, the pentacene film thickness dependence on FET characteristics showed that a channel sheet with a thickness less than 20 nm is formed at the pentacene/SiO2 interface. Finally, the employment of the Maxwell–Wagner model for the analysis of the C–V characteristics was shown to give a good approximation even when taking into account the presence of a charge sheet at the interface.