Hybrid small-signal model parameter extraction of GaN HEMTs on Si and SiC substrates based on global optimization

This article presents efficient parameters extraction procedure applied to GaN High electron mobility transistor (HEMT) on Si and SiC substrates. The method depends on combined technique of direct and optimization-based to extract the elements of small-signal equivalent circuit model (SSECM) for GaN-on-Si HEMT. The same model has been also applied to GaN-on-SiC substrate to evaluate the effect of the substrates on the model parameters. The quality of extraction was evaluated by means of S-parameter fitting at pinch-off and active bias conditions.