Performance, Reliability, and Robustness of 4H-SiC Power DMOSFETs

Abstract

In this paper, we review the performance, reliability, and robustness of the current 4H-SiC power DMOSFETs. Due to advances in device and materials technology, high power, large area 4H-SiC power DMOSFETs (1200 V, 67 A and 3000 V, 30 A) can be fabricated with reasonable yields. The availability of large area devices has enabled the demonstration of the first MW class, all SiC power modules. Evaluations of 1200 V 4H-SiC DMOSFETs showed that the devices offer avalanche power exceeding those of commercially available silicon power MOSFETs, and have the sufficient short circuit robustness required in most motor drive applications. A recent TDDB study showed that the gate oxides in 4H-SiC MOSFETs have good reliability, with a 100-year lifetime at 375oC if Eox is limited to 3.9 MV/cm. Future work on MOS reliability should be focused on Vth shifts, instead of catastrophic failures of gate oxides.