FW‐EM‐based approach for scalable small‐signal modeling of GaN HEMT with consideration of temperature‐dependent resistances

In this paper, the full‐wave electromagnetic (FW‐EM) simulation approach for scalable small‐signal modeling of the GaN HEMT device is proposed. The scalable rules are deduced from the extracted parasitic parameters, which is according to a step‐by‐step parameter extraction method. Moreover, the accuracy is enhanced by considering the temperature‐dependent resistance (TDR) Rs and Rd, which are calculated by combining a universal thermal resistance model and the Rs and Rd under the pinch‐off condition. In the end, a set of GaN HEMT with a gate length of 0.25 μm is used for validation, and the experimental results show that good agreements have been achieved between the measured and the simulated scattering (S) parameters.