Physics-Based Large-Signal and Trap Modeling of GaN HEMTs

This talk provides a strategy and useful insights for modeling the trapping effects in microwave PA designs based on GaN HEMT technology. We present an extended analysis of a trap description for the compact model ASM HEMT and its extraction procedure. Commonly used dopants in the buffer of GaN HEMTs such as iron enhance dispersive effects and often result in significant mismatch between model and real behavior of the device. Commercially available pulsed IV/ RF measurement systems can be utilized to both extract transistor model parameters and trapping characteristics. We provide a simple method to include the effects of drain-lag and use a parameter scaling technique to improve model accuracy. Measurement and simulation examples comparing the model with and without the trap description will be presented and discussed.