Characterization of V-Shaped Defects Formed during the 4H-SiC Solution Growth by Transmission Electron Microscopy and X-ray Topography Analysis

Abstract

Defects generated during 4H-SiC (0001) solution growth have been investigated by synchrotron X-ray topography and transmission electron microscopy (TEM). The defects unidentified before are recognized as V-shaped contrast features in the X-ray topographic images. The detailed analysis combining TEM results revealed that the newly generated defects are identified as a pair of dislocations on a basal plane with opposite Burgers vectors parallel to the [112̅0] direction. It is found that no defects in the substrate are directly associated with the formation of the V-shaped defects. Geometric analysis of the size and shape of the V-shaped defects indicates that they nucleate in pairs intermittently during the growth process. On the basis of the observed morphology of these defect configurations, a mechanism of two-dimensional nucleation during solution growth is postulated for the generation of the V-shaped defects.