Single crystals were grown using the physical vapour transport method under various thermoelastic stress conditions, and the degree of basal-plane bending in the crystals was characterized by using peak-shift measurements of X-ray rocking curves. The results indicated that the degree of basal-plane bending depended largely upon the magnitude of the thermoelastic stresses imposed upon the crystals during physical vapour transport growth. Quantitative analysis of the basal-plane bending revealed that the density of basal-plane dislocations, estimated from the basal-plane bending, was much smaller than that deduced using defect-selective etching. It was also found that the basal-plane dislocation density was related to the threading screw dislocation density in physical vapour transport-grown SiC crystals. These features of basal-plane dislocations were explained in terms of a basal-plane dislocation-multiplication process which was triggered by the intersection of basal-plane dislocations with a forest of threading screw dislocations extending along the c-axis.

Analysis of Basal Plane Bending and Basal Plane Dislocations in 4H-SiC Single Crystals. N.Ohtani, M.Katsuno, T.Fujimoto, M.Nakabayashi, H.Tsuge, H.Yashiro, T.Aigo, H.Hirano, T.Hoshino, W.Ohashi: Japanese Journal of Applied Physics, 2009, 48[6], 065503