Direct extraction of carrier mobility in graphene field-effect transistor using current-voltage and capacitance-voltage measurements

Top gated graphene field-effect transistors were fabricated using yttrium oxide film as high-κ gate dielectric, and the gate voltage dependent drain current and gate capacitance characteristics were both measured on one graphene device. Based on the two kinds of data sets, we developed a method to extract the carrier mobility of graphene field-effect transistors, along with some other parameters, such as series resistance and residual carrier density. Prior to previous method, this method could well fit the transfer curve of graphene field-effect transistor with high gate oxide capacitance since its carrier concentration is directly obtained from the experimental data rather than from analytic equation.