High energy proton irradiation effects on SiC Schottky rectifiers

4H-SiC Schottky rectifiers with dielectric overlap edge termination were exposed to 40 MeV protons at fluences from 5x10(7)-5x10(9) cm(-2). The reverse breakdown voltage decreased from similar to500 V in unirradiated devices to similar to-450 V after the highest proton dose. The reverse leakage current at -250 V was approximately doubled under these conditions. The forward current at -2 V decreased by similar to1% (fluence of 5x10(7) cm(-2)) to similar to42% (fluence of 5x10(9) cm(-2)), while the current at lower biases was increased due to the introduction of defect centers. The ideality factor, on-state resistance, and forward turn-on voltage showed modest increases for fluences of less than or equal to5x10(8) cm(-2), but were more strongly affected (increase of 40%-75%) at the highest dose employed. (C) 2002 American Institute of Physics.