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

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/SiO 2 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.