The Gate Oxide Breakdown Failures of 4H-SiC MOS Devices

A study of Weibull distribution of 4H-SiC MOS capacitors has shown the effect of temperature as well as electric-field stress on the analysis of time-dependent breakdown. Time-Dependent Dielectric Breakdown (TDDB) is strongly electric-field dependent and temperature-dependent. In the paper, the test was at the stress level of 9.5, 10, and 10.5 MV/cm under 373K, through the TDDB model, the lifetime of the SiO2 can reach more than 30 years when the field pressure is not more than 6.6 MV /cm. The acceleration factor for TDDB (using E-Model) under different temperature stress, it expected that the capacitors would last for 2.28×107 years under 3MV/cm or 54 years under 6MV/cm at 373K.