Long term operation of 4.5kV PiN and 2.5kV JBS diodes

Abstract

Large area SiC diodes (20mm(2) and 40mm(2)) for high power applications were manufactured on selected defect free areas of 4H Epi wafers. The forward and reverse characteristics of these 4.5kV PiN and 2.5kV JBS diodes are analyzed. Various device nonidealities are discussed and compared to known crystal imperfections. Large PiN diodes were parallel connected together with silicon IGBT switches using conventional press-pack technology. Dynamic switching up to 1250V and 400A nominal current is reported. Long term data for continuos switching revealed a new drift phenomena of the forward voltage drop of bipolar diodes. However, long term blocking tests confirmed reliable reverse characteristics.