The electrical and crystalline properties of micro-pipe defects were studied in n-type 4H bulk samples by using Raman imaging techniques. A clear decrease in the carrier concentration and mobility in the vicinity of micro-pipes was observed; thus indicating the existence of carrier trapping centres. Experiments which were performed at temperatures of up to 1200C showed that the thermal excitation of carriers was negligibly small. This suggested that the trap levels were relatively deep.

Raman Imaging Characterization of Electric Properties of SiC near a Micro-Pipe. H.Harima, T.Hosoda, S.Nakashima: Materials Science Forum, 2000, 338-342, 603-6