Study of the real structure of basal-plane-faceted sapphire ribbons

Abstract

The structure of basal-plane-faceted sapphire ribbons with cross sections of 30 × 1.5 and 50 × 1.5 mm, grown by the Stepanov method, has been investigated using X-ray diffraction topography and selective etching. The model of block formation in such ribbons through interaction of dislocations of prismatic slip system is confirmed. The role of gas bubbles as stress concentrators and dislocation sources is established. It is shown that the dislocations of basal-slip system are involved in the development the low-angle boundaries and block formation.