Abstract: The six sapphire ribbons single crystal was grown by edge defined film fed growth (EFG) method.Single crystal size is 350 mm×80 mm×2 mm.The appropriate thermal field as the radial temperature 2.9-4.6 K/mm and growth speed control between 5-10 mm/h were determined by CGSim simulation software simulation calculation and experimental verification.The crystallization of the crystal had proved by test crystal rocking curve, the peak intensity is very high and symmetry, and rocking curve of half high FWHM is 16.946″.The crystallization of the crystal is good.Crystal dislocation density was calculated through corrosion in level 103, and the middle crystal dislocation density is less than the crystal on both sides.The bending strength of six sapphire ribbons single crystal was tested, and the highest strength is 1583 MPa, the middle crystal strength is greater than both sides.

Key words: The six sapphire ribbons single crystal was grown by edge defined film fed growth (EFG) method.Single crystal size is 350 mm×80 mm×2 mm.The appropriate thermal field as the radial temperature 2.9-4.6 K/mm and growth speed control between 5-10 mm/h were determined by CGSim simulation software simulation calculation and experimental verification.The crystallization of the crystal had proved by test crystal rocking curve, the peak intensity is very high and symmetry, and rocking curve of half high FWHM is 16.946″.The crystallization of the crystal is good.Crystal dislocation density was calculated through corrosion in level 103, and the middle crystal dislocation density is less than the crystal on both sides.The bending strength of six sapphire ribbons single crystal was tested, and the highest strength is 1583 MPa, the middle crystal strength is greater than both sides.