Light emission from interface traps and bulk defects in SiC MOSFETs

Images and spectra of light emission have been observed in 4H and 6HSiC n-type MOSFETs originating from electron-hole recombination at interface traps and from the bulk under the channel. Low mobility and high interface trap density impedes the flow of electrons into the channel. Its time evolution was imaged. It is slower in 4H than in 6H MOSFETs due to the lower channel mobility and higher interface trap density in the former. Emission images reveal triangular shaped 3C inclusions and these defects were found to alter the formation of the inversion layer.