Self-heating is an important issue for GaN heterostructure field effect transistors (HFETs),
especially in high power applications. Here we report the temperature dependence of the dc
characteristics of some GaN HFETs including the variation of the transconductance. We
present the characteristics as a function of added power, instead of voltage bias, and use the
temperature data to transform the power dependence into a dependence on the average
device temperature. For similar devices on sapphire and SiC, at 20 VV DS and 0 VVG⁠, the …