Influence of physical parameters and piezoelectric polarization on charge control characteristics of Si3N4/AlGaN/GaN M̲etal I̲nsulator S̲emiconductor H̲eterostructure F̲ield E̲ffect T̲ransistor (MISHFET)

An accurate non linear charge-control model of the two dimensional electron gas (2-DEG) of an insulated gate AlGaN/GaN HFET is proposed which incorporates the dominant effect of polarization induced charge at the AlGaN/GaN interface. It is based on new polynomial dependence of sheet carrier density on position of quasi Fermi level to consider the quantum effects and to validate it from sub threshold region to high conduction region. The model gives an accurate description of the device operation for a wide range of physical parameters. The results obtained agree well with the published data.