Device Simulation of Density of Interface States of Temperature Dependent Carrier Concentration in 4H-SiC MOSFETs

Abstract

Interface traps play an important role in the SiO2/4H-SiC interface. They are crucial issues for the current and trans-conductance in 4H-SiC MOSFET devices. In this thesis, we present a temperature and bias dependent model for simulations of trap occupation and also carrier concentration in a 4H-SiC MOSFET device. By fitting the Hall measurement data [1], we have various parameters for simulation, including the fixed oxide charge density and the interface trap density of states profile. These simulations enable us to observe temperature dependence of occupied trap densities and inversion layer carrier concentrations. In addition, bias dependence of trap density and occupation probability at different temperatures is also presented. ii