Impact of carbon in the buffer on power switching GaN-on-Si and RF GaN-on-SiC HEMTs

Abstract This article addresses the impact of buffer doping on critical performance issues current-collapse and dynamic R ON in GaN high electron mobility transistors. It focusses effect carbon, either incorporated deliberately GaN-on-Si power switches, or as a background impurity iron doped RF GaN-on-SiC devices. The commonality is that carbon results epitaxial becoming p-type hence electrically isolated from two-dimensional gas by P–N junction. Simulations which incorporate model for leakage along dislocations are used to show remarkably wide range experimental observations can be explained including complex time dependence drain current transients switches. In devices, current-collapse, dynamics, kink effect, pulse-IV electric field distribution gate-drain gap all explained.