Aluminium Oxide (Al2O3) is a amphoteric oxide of aluminium. Usually it’s called Alumina, it’s naturally produced by corundum, ruby and sapphire,maily used as raw material of metal aluminium.Besides,it can also be used as polishing powder with the nature of its degree of hardness,infractory material with the nature its high melt point. Sapphire single crystal for semiconductor use is made by CZ,Kyropoulos and EFG methods. Sapphire wafer is used as LED substrate and laser substrate for optical device. Furthermore,sapphire wafer is also used as window material to show high transmissivity in a wide frequency range from ultraviolet area to infrared area.