Stability of SiC Schottky Rectifiers to Rapid Thermal Annealing

4H-SiC Schottky rectifiers with dielectric overlap edge termination were rapid thermal annealed at temperatures from 700 to 1100°C for periods of 60-240 s under ambient. The forward turn-on voltage ideality factor and on-state resistance were all improved by anneals <1000°C. At higher temperatures and longer duration, the Ni Schottky contact showed ohmic behavior and degraded surface morphology. Since the reverse characteristics were less affected by the lower temperature anneals than the forward characteristics, the diodes exhibited an increase in on/off ratio of up to ∼20%.