Investigations of 900V 4H-SiC Planar Power MOSFET for More Robust Reliability Performance

In this paper, planar SiC 900 V 60 mΩ MOSFET was investigated with gate oxide reliability by gate oxide integrity and intrinsic TDDB measurement. The gate oxide showed reliable VBD of 46 V capacity and good TDDB lifetime performance. The intrinsic TDDB lifetime follows the linear E-model allows a confidential prediction of the failure rate within the lifetime less than 0.1 ppm in 20 years for +18 V and 175 °C temperature use conditions with wafers and TO-247 packages. Avalanche ruggedness was also confirmed by measurement the ruptured distribution by unclamped inductive switching (UIS) and investigated the failure location. Avalanche stability of BVDSS was confirmed and was showing reliable and robust over 900 V BVDSS.