AlGaN/GaN Diodes with Ni Schottky Barrier and Recessed Anodes

In this paper, we investigate influence of anode recess on AlGaN/GaN Schottky barrier diodes (SBD) DC characteristics. It is shown that anodes recess depth increment leads to rise of forward and reverse current and decrease of breakdown voltage. AlGaN barrier thickness was 10 nm. The forward voltage (at 100 mA/mm forward current) for diodes with 7 μm anode-cathode distance was 1.84 V, 1.64 V, 1.46 V and 1.55 V for 0, 5 nm, 7.5 nm and 12.5 anodes recess respectively. The breakdown voltage for diodes was 345 V, 305 V, 230 V and 250 V for 0, 5 nm, 7.5 nm and 12.5 anodes recess respectively. The leakage current was 1.3 μA/mm, 11 μA/mm, 42 μA/mm and 35 μA/mm for 0, 5 nm, 7.5 nm and 12.5 anodes recess respectively. The best forward to leakage current ratio I
_F
/I
_L
= 27000 achieved at zero recess.