Characteristics of GaN MOSFET with stacked gate dielectric of MgO and TiO2

This paper demonstrates the electrical characteristics of stacked-gate enhancement mode n-channel gallium nitride (GaN) based metal-oxide-semiconductor field effect transistor. Magnesium oxide and titanium oxide are used as stacked gate dielectrics. Use of these oxides shows promising characteristics with GaN. Thickness variation of stacked gate oxides while keeping total oxide thickness constant shows significant effect in device performance including drain current, threshold voltage, transconductance, gate leakage current and device breakdown characteristics. Effect of dielectric thickness variation on drain induced barrier lowering (DIBL) and I_on/I_off ratio are also analysed. Two dimensional simulation is used to predict the effect of thickness variation of stacked-gate-oxide on electrical characteristics of GaN based metal-oxide-semiconductor field effect transistor.