Semi analytical modeling of quantum capacitance of graphene-based ion sensitive field effect transistor

Abstract

Quantum capacitance as a one of the main characteristics of FET devices is in our focus in this paper. The quantum capacitance of graphene-based ion sensitive FET with an equivalent circuit is presented and also based on the analytical model a numerical solution is reported. The temperature effect on the quantum capacitance is highlighted, in which minimum capacitance dramatically rises by increasing the temperature. Furthermore, the capacitance model is adopted to derive current- voltage characteristic of the proposed device for different gate-source voltages. As the Vgs increases from 0.2 to 0.5 v, drain current (ID) is also rising. To further confirm this viewpoint, the presented analytical model is compared with experimental data and acceptable agreement is reported.