Analysis of the growth conditions of long single crystalline basal-plane-faceted sapphire ribbons by the Stepanov/EFG technique

The influence of the growth conditions and process parameters on the formation of blocks during growth of basal-plane-faceted single crystalline sapphire ribbons by the Stepanov/EFG technique was investigated. A number of modifications of the crystallization unit were used to vary systematically the crystal growth conditions. The results gave clearly the growth conditions which are favorable to get blocks-free single crystalline basal-plane-faceted sapphire ribbons.

► Sapphire crystal growth by the Stepanov/EFG technique. ► Favorable growth conditions for basal-plane-faceted sapphire ribbons. ► Avoidance of meniscus instabilities and application of low thermal stress conditions.