Dislocation constraint in the growth of crystals by using the modified Lely method was studied. In SiC single-crystal growth, the dislocations and defects generally propagated from the seed crystal surface. However, when etching-back of the seed crystal surface in the sublimation process was performed before growth, defects and dislocation propagation in the interface between the seed crystal and the grown crystal were reasonably suppressed. The switchover from etching-back to growth could be performed without changing the heating conditions during the initial process. It was noticed that the density of micropipes in the grown crystal was decreased to one-tenth as compared with that of the seed crystal used. It was concluded that etching-back of the seed crystal was 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