Reliability Testing of SiC JBS Diodes for Harsh Environment Operation

Silicon carbide (SiC) semiconductor devices are actively being designed into high voltage power conversion systems for outdoor applications. Today's system designers seek confidence in the dependability of these devices under high voltage, high humidity operation in these conditions. This work proposes a variation of the H3TRB test for reliability qualification, with reverse bias set at 80% rated blocking voltage. New diodes from Wolfspeed, a Cree Company, designed with additional environmental resistance, were built into modules and subjected to the new test by Vincotech GmbH to independently verify the reliability. No failures or physical degradation of the devices were detected after 2000 hours of stress testing.