Harmonic balance simulation of a new physics based model of the AlGaN/GaN HFET

HFETs fabricated with nitride-based wide bandgap materials are capable of producing high RF output power and are promising for the next generation radar and wireless communication systems. To take full advantage of this new kind of device, large-signal models suitable for use in commercial microwave circuit simulators are desirable, but existing models can only interpolate or fit data that has been measured from previously fabricated devices. In this study, a new physics-based large-signal model for AlGaN/GaN HFETs is introduced that can predict the large-signal performance of an HFET from its design parameters. It couples a compact physics-based DC module with a harmonic balance RF module. This new model is shown to agree with both DC and RF experimental data without any adjustable fitting parameters for the device. The DC IV and transconductance curves predicted by this new model also agree with those generated by a commercial 2D simulator.