Low ON-Resistance Fully-Vertical GaN-on-SiC Schottky Barrier Diode with Conductive Buffer Layer

In this paper, a low ON-resistance fully-vertical GaN-on-SiC Schottky barrier diode (SBD) has been demonstrated by virtue of highly conductive AlGaN buffer structure. By adopting a heavily Si-doped Al0.25Ga0.75N buffer layer on top of SiC substrate and incorporating a graded Al0.25 -> 0Ga0.75 -> 1N at the GaN/buffer interface, the conductivity in the vertical configuration can be enhanced such that the differential specific ON-resistance of the fully-vertical GaN-on-SiC SBD can be effectively reduced to 0.96 m Omega.cm(2). The fully-vertical GaN-on-SiC SBD exhibits nearly ideal Schottky contact with an ideality factor of similar to 1.03, a high current swing of similar to 10(11), and a breakdown voltage of 528 V with fluorine-implanted termination. The demonstration of the low ON-resistance fully-vertical GaN-on-SiC SBD paves the way towards fully-vertical GaN-on-SiC power devices and the monolithic integration of GaN/SiC power devices.