Capacitance-voltage and current-voltage characteristics of graphite oxide thin films patterned by ultraviolet photolithography

Electrical characteristics of graphite oxide (GO) thin films deposited on a p-type silicon substrate were investigated to explore its potential application as a dielectric material in organic field effect transistors. Channel current in the GO films exhibited linear response with the applied bias in the positive voltage regime and increased exponentially for negative source-drain bias. This rectifying behavior arises due to the Coulombic interaction between the electrons emitted from the metal contact and the space charge region in the GO film. A clockwise hysteresis loop was observed in the capacitance-voltage characteristics due to the presence of traps at the interface.