High voltage GaN Schottky rectifiers

Mesa and planar GaN Schottky diode rectifiers vith reverse breakdown voltages (V-RB) up to 550 and >2000 V,respectively. hare been fabricated, The on-state resistance, R-ON, was 6 m Ohm.cm(2) and 0.8 Ohm cm(2), respectivetly, producing figure-of-merit values for (V-RB)(2)/R-ON in the range 5-48 MW.cm(-2). At low biases the reverse leakage current was proportional to the size of the rectifying contact perimeter, while at high biases the current was proportional to the area of this contact. These results suggest that at low reverse biases, the leakage is dominated bg the surface component, while at higher biases the bulk component dominates. On state voltages were 3.5 V for the 550 V diodes and greater than or equal to 15 for the 2 kV diodes. Reverse recovery times were <0.2 mu s for devices switched from a forward current density of similar to 500 A.cm(-2) to a reverse bias of 100 V.