Interpretation and modelling of dynamic-R-ON kinetics in GaN-on-Si HEMTs for mm-wave applications

Abstract

This work shows that the complex dynamic-R-ON characteristics observed for scaled GaN HEMT devices results from the similar capture/emission activation energies of the defects present in different epitaxial layers. This work also (i) presents an optimized experimental scheme for a detailed analysis of the different charge-trapping mechanisms in GaN-on-Si HEMTs, (ii) describes the charge-trapping kinetics over a wide range of temperatures using capture/emission time (CET) maps, and (iii) models the defect energy distribution in the AlGaN barrier by analytically deriving the 2D potential profile in the access region and combining it with the results from CET maps.