CRYOGENIC OPERATION OF P-I-N POWER RECTIFIERS

The results of detailed measurements and modeling on 1200 V P-i-N diod es over a temperature range of 300-77 K are presented in this paper. A t typical rated current levels, the forward voltage drop increases wit h a decrease in temperature. Analysis and measurements prove that ther e is an order of magnitude reduction in the i-region stored charge fro m 300 to 77 K. This results in greatly reduced switching losses at 77 K. An analytical model, including end region recombination with bandga p narrowing, is presented to explain the experimental observations.