Multi-Channel Tri-Gate GaN Power Schottky Diodes With Low ON-Resistance

In this letter, we demonstrate high-performance lateral GaN power Schottky barrier diodes based on a novel multi-channel tri-gate architecture. A significant reduction in ON-resistance (RON) of 50%, down to7.2 ± 0.4~Ω · mm, along with a much smaller forward voltage (VF) of 1.57 ± 0.06 V, were achieved with multiple 2DEG channels (multi-channels) formed by periodic AlGaN/GaN heterostructures. We used a tri-anode structure to form Schottky contact to the multi-channels through the fin sidewalls, leading to a small turn- ON voltage (VON) of 0.67 ± 0.04 V. To simultaneously control the multi-channels and effectively spread the electric field in OFF state, a tri-gate structure was integrated in the anode, resulting in an ultra-low leakage current (IR) of ~1 nA/mm at −600 V and a high breakdown voltage (VBR) of −900 V at1~μA/mm with grounded substrate. In addition, the devices presented promising switching performance, due to the small product ofRONand reverse charge (Q), thanks to the optimized tri-gate geometry, and high effective mobility (μ ₑ) of 2063 ± 123 cm2·V−1s−1despite the small fin width (w) of 50 nm. Our approach combines in a unique way the excellent electrostatic control of the tri-gate structure with the high conductivity of multi-channels, offering a promising platform for future advances in GaN power devices.