The ramification of micro-pipes was observed using scanning electron microscopy, optical microscopy, and synchrotron X-ray radiography. The conditions for the ramification of dislocated micro-pipes were determined theoretically within a model when the angles between dislocation lines were small. It was shown that the ramification of micro-pipes into two smaller ones was possible only for micro-pipes with radii that exceed the equilibrium micro-pipe radius and was associated with a decrease in the total micro-pipe surface area.

Ramification of Micropipes in SiC Crystals. M.Y.Gutkin, A.G.Sheinerman, T.S.Argunova, J.H.Je, H.S.Kang, Y.Hwu, W.L.Tsai: Journal of Applied Physics, 2002, 92[2], 889-94