AlGaN/GaN HEMTs on (001) silicon substrates

Abstract

AlGaN/GaN high electron mobility transistors have been realised on resistive Si(001) substrate. The heterostructure was grown by molecular beam epitaxy. The 2D electron gas formed at the AlGaN/GaN interface exhibits a sheet carrier density of 7.1×1012 cm−2 and a Hall mobility of 1500 cm2/V s at room temperature. High electron mobility transistors with a gate length of 3 µm have been processed and DC characteristics have been achieved. A maximum drain current of more than 440 mA/mm and a transconductance gm of 120 mS/mm have been obtained. These encouraging results open the way for GaN-based electronic applications on Si(001) substrates.