Small Signal Modeling of GaN-on-Si HEMT with Leaky Buffer

This letter reports on AlGaN/GaN high-electron mobility transistors (HEMTs) on high-resistive silicon substrate using a modified Small-signal model to improve the simulation accuracy of S-parameters. Compared with conventional Small- signal model our model can simulate the leaky buffer effect, significantly increased the S-parameters simulation. The key reasons for improved the simulation results are due to the additional capacitances and resistances added in the model. The maximum oscillation frequency fmax is 62.8 GHz and current gain cut off frequency fT is 63.81 GHz after de-embedding.