Modeling of the reverse gate leakage in AlGaN/GaN high electron mobility transistors

The high gate leakage of AlGaN/GaN HEMTs grown on sapphire/SiC substrates having x=0.2, AlGaN thickness of 30 nm, and zero drain-source bias was earlier explained using the thermionic trap-assisted tunneling model. In the present work, we show that the same model can explain the gate leakage in AlGaN/GaN HEMTs grown on silicon substrates, having aluminum compositions of 24%, 26%, and 31%, AlGaN thickness of 20 nm, and drain-source bias (VDS) of 10 V, over the gate-source voltages above threshold.