Growth defects in flux-grown single crystals were investigated by using chemical etching and synchrotron radiation techniques. Band-shaped and polysynthetic twins were detected, by optical microscopy, due to differences in etching rate between the host crystal and the twin. The orientations and symmetries of the twins were deduced from their etching patterns. Large numbers of etch pits with regular shapes were also found on the surface. These etch pits corresponded to outcrops of dislocations which originated from the seed crystal or from inclusions.

X.B.Hu, S.S.Jiang, X.R.Huang, W.J.Liu, C.Z.Ge, J.Y.Wang, H.F.Pan, J.H.Jiang, Z.G.Wang: Journal of Crystal Growth, 1997, 173, 460-6