Chalmers GaN HEMT charge model revisited

This paper presents a charge modeling procedure based on the Chalmers GaN HEMT charge model. The impact of the transcapacitances in large-signal charge modeling is investigated. It is shown that the direct use of the determined capacitance model parameters in the charge model is impossible, for the transcapacitances caused by the two bias-voltage dependent charges should be taken into account when the parameters are determined. Finally, it is also shown that the use of the charge model accounting for transcapacitance effects dramatically improves the Y-parameter and large-signal simulation results, which is verified by comparing the measured and simulated Y-parameters and large-signal behaviors.