Effects of N{sub}2O Anneal on Channel Mobility of 4H-SiC MOSFET and Gate Oxide Reliability

摘要

The effect of N{sub}2O anneal on channel mobility of inversion-type 4H-SiC n-channel MOSFET has been systematically investigated. It is found that the mobility increases with increasing anneal temperature from 900 to 1150°C. The highest field effect mobility of 30 cm{sup}2/Vs is achieved by 1150°C anneal for 3 h, which is about 20 times higher than that for non-annealed MOSFET. In order to investigate the oxide reliability, TDDB measurement has been performed on SiO{sub}2 grown on n-type 4H-SiC. The oxide lifetime is found to be drastically improved by N{sub}2O anneal.