Demonstration of a 9 kV reverse breakdown and 59 mΩ-cm2 specific on-resistance AlGaN/GaN Schottky barrier diode

Abstract Al 0.26 Ga 0.74 N/GaN on SiC lateral Schottky diodes were fabricated with variable anode-to-cathode spacing and were analyzed for blocking and on-state device performance. On-chip normally-on High Electron Mobility Transistor (HEMT) structures were also fabricated for a comparison of blocking characteristics. The Schottky diode displayed an ideality factor of 1.59 with a Ni/AlGaN zero bias barrier height of 1.18 eV and a flat band barrier height of 1.59 eV. For anode-to-cathode spacings between 10 and 100 μm, an increase in median breakdown voltages from 529 V to 8519 V and median specific on-resistance ( R on-sp ) from 1.5 to 60.7 mΩ cm 2 was observed with an increase in spacing. The highest performing diode had a lateral figure of merit of 1.37 GW/cm 2 corresponding to a breakdown voltage upwards of 9 kV and a R on-sp of 59 mΩ cm 2 . This corresponds to the highest Schottky diode breakdown voltage reported thus far with an Al 0.26 Ga 0.74 N/GaN lateral structure.