Comparison of AC and DC BTI in SiC Power MOSFETs

In this work we compared AC and DC bias temperature instability (BTI) degradations induced by stressing the channel and Junction-FET regions in 4H polytype n-channel Silicon Carbide (SiC) based power MOSFETs. We observed that the degradation caused by AC BTI stress is dependent on the device technology generation unlike the DC BTI stress degradation, which is found to be independent of technology generation. Also, we found that the AC BTI stress causes more permanent damage to the device due to the creation of interface traps and border traps in contrast to DC BTI where only border traps are responsible for the degradation.