Comparison of high field characteristics of SiO_2 and AIN gate insulators in 6H SiC MOS capacitors

摘要

Using a fast ramp response technique, the high field characteristics, specifically the breakdown strength, of thermally grown silicon-dioxide (SiO_2) and MOCVD grown aluminum-nitride (AlN), on n-type 6H-SiC epilayers is obtained as a function of three different procesing conditions for the insulator grwoth. Significant improvement in the breakdown strength of thermally grown SiO_2 after a 30 minute post annealing at 400 deg in nitrogen ambient is reported. Further, the influence of temperature profile during the AlN growth on the breakdown strength is reported.