METHOD FOR GROWTH OF SAPPHIRE SINGLE CRYSTALS GROWTH Russian patent published in 2009 - IPC C30B15/00 C30B15/20 C30B29/20 

FIELD: technological processes.

SUBSTANCE: invention is related to the field of sapphire single crystals growth and may be used in optical, chemical and electronic industry. Method includes vacuum melting of initial charge in chamber, single crystal pulling to seeding agent with its growth at simultaneous cooling of melt and further cooling of grown single crystal. Prior to beginning of single crystal growth additionally links are grown, at that height of links corresponds to height of observed melt meniscus and is equal to 0.5-4.0 mm, and time of their growth makes 1-20 minutes, at that crystallisation process is controlled by means of heater power reduction and provision of specified linear speed of crystallisation, and cooling of single crystal is done in vacuum for 30-35 hours with further delay for 10-12 hours in argon atmosphere at the pressure of 0.5 kgf/cm² in chamber, opening of chamber cover and single crystal unloading.

EFFECT: large single crystals of sapphire with high structural perfection; increased service life of device due to control and limitation of melt superheating temperature, control of hardening beginning temperature and crystallisation speed.

4 ex