Large signal frequency dispersion of AlGaN GaN heterostructure field effect transistors

Microwave AlGaN/GaN MODFET power devices have been analysed with respect to their frequency dispersion in terms of transconductance, gate capacitance and large signal output current swing. A electrical equivalent circuit mode l consistent with all experimental findings, based on the incorporation of a lossy dielectric layer, is presented. It may also enable an interpretatio n to be made of the RF power compression observed in these devices.