A New 1200V SiC MPS Diode with Improved Performance and Ruggedness

Abstract

Infineon’s 5 th Generation of 1200V SiC diodes uses a new compact chip design, realized by an optimized hexagonal merged-pn cell structure in the active area. This allows a higher n-doping in the epi layer due to improved E-field shielding resulting in a smaller differential resistance per chip area. Thanks to the merged-pn cell structure, depending on the diode ampere rating, a surge current capability now rated up to 14 times the nominal current ensures robust diode operation during surge current events in the application. The previous generations of 1200V SiC diodes could not make full use of the high breakdown field strength of the SiC material due to the instable avalanche which occurs at the edge termination only, and therefore, requiring a significant safety margin between rated voltage and breakdown voltage. Now the 5 th Generation is designed in a way that each cell contributes to the avalanche, enabling a much more avalanche rugged device.