About synthetic sapphire crystal

Sapphire Properties

The Kyropoulos process (KY process) for sapphire crystal growth is currently used by many companies in China to produce sapphire for the electronics and optics industries.
High-purity, aluminum oxide is melted in a crucible at over 2100 degrees Celsius. Typically the crucible is made of tungsten or molybdenum. A precisely oriented seed crystal is dipped into the molten alumina. The seed crystal is slowly pulled upwards and may be rotated simultaneously. By precisely controlling the temperature gradients, rate of pulling and rate of temperature decrease, it is possible to produce a large, single-crystal, roughly cylindrical ingot from the melt.
After single crystal sapphire boules are grown, they are core-drilled into cylindrical rods, The rods are sliced up into the desired window thickness and finally polished to the desired surface finish.