Dislocation constraint in the growth of SiC crystal by the modified Lely method was studied. In SiC single crystal growth, the dislocations and defects generally propagate from the seed crystal surface. However, when the etch back on the seed crystal surface in the sublimation process was performed prior to growth, defects and dislocation propagation in the interface between the seed crystal and the grown crystal were suppressed reasonably. The switchover from the etch back to the growth could be performed without changing heating condition during the initial process. It was noticed that the density of the hollow defects called as micro-pipes in the grown crystal were decreased to one tenth as compared to that of the seed crystal used. The etch-back process of the seed crystal was considered to be an effective method for constraining defects during SiC crystal growth.

Dislocation Constraint by Etch-Back Process of Seed Crystal in SiC Sublimation Growth. T.Kato, S.I.Nishizawa, K.Arai: Journal of Crystal Growth, 2001, 233[1-2], 219-25