The improvement of DC performance in AlGaN-GaNHEFTs with isoelectronic Al-doped channels

Abstract

Enhancement of electrical properties of an AlGaN-GaN heterostructure was achieved through isoelectronic A1-doping of the undoped channel layer during the growth by metal-organic chemical vapor deposition. The two-dimensional electron gas mobility was increased from 3390 to 4870 cm(2)/V(.)s at 77 K, and the crystal quality was significantly improved as A1 atoms were incorporated in the undoped GaN film. The AlGaN-GaN HFETs were fabricated on this material structure and exhibited a maximum drain current of 909 mA/mm, and a maximum transconductance of 232 mS/mm, corresponding to an increase of 30% and 21%, respectively.