Formation Mechanism of Stacking Faults in PVT 4H-SiC Created by Deflection of Threading Dislocations with Burgers Vector c+a

Abstract

Synchrotron White Beam X-ray Topography studies are presented of dislocation behavior and interactions in a new generation of seventy-six millimeter diameter, 4H-SiC wafers grown using Physical Vapor Transport under specially designed low stress conditions. Such low stress growth conditions have enabled reductions of dislocation density by two or three orders of magnitude compared to the lowest previously reported levels [1]. In this paper, detailed topography analysis will be presented of the deflection of threading dislocations with Burgers vectors of c and c+a onto the basal plane leading to reductions of the density of such dislocations down to levels of ~187 cm-2. The deflection of the latter type of dislocations produces complex faulted defect configurations and models for their creation are presented and discussed.