Micro-Photoluminescence Mapping of Defect Structures in SiC Wafers

Micro-photoluminescence can be used to image electrically active structural defects in SiC. Under suitable excitation conditions it is possible to observe both band-edge PL and near bandedge PL from recombination via a shallow boron acceptor. The intensity of the band-edge emission is related to the carrier lifetime - and is reduced by the presence of structural or interfacial defects. The intensity of the deep level PL is a complex function of the number of radiative centers and the number of centers limiting carrier lifetime. Micro-PL mapping can provide information on the spatial distribution of electrically active defects in SiC.