Investigation of Quaternary Barrier InAlGaN/GaN/AlGaN Double-Heterojunction High-Electron-Mobility Transistors (HEMTs) for High-Speed and High-Power Applications

Abstract

We report direct current (DC) and microwave performance of a 50-nm gate length ( L g ) quaternary-based InAlGaN/GaN/AlGaN high-electron-mobility transistor (HEMT) on SiC substrate with SiN passivation and by using a T-gate. The proposed HEMT structure is simulated using industry-standard Synopsys Sentaurus technology computer-aided design (TCAD). The regrown n++ GaN source/drain ohmic contacts show a peak drain current density ( I dmax ) of 2.9\xa0A/mm along with low on-resistance of 0.49\xa0Ω\xa0mm. A record power gain cut-off frequency ( f max ) of 425\xa0GHz along with current gain cut-off frequency ( f t ) of 310\xa0GHz are obtained by the substantial reduction in the device s intrinsic and extrinsic parasitic resistances and capacitances. A very thin 7-nm In 0.13 Al 0.83 Ga 0.04 N quaternary barrier with an AlGaN back-barrier structure effectively mitigates the short-channel effect with an improved breakdown voltage ( V BR ) of 38\xa0V. The prominent DC and microwave characteristics of the proposed HEMT make it an appropriate candidate for next-generation high-power millimeter-wave electronics.