US Patent 7462238 Crystal growth apparatus and method of producing a crystal

A crystal growth apparatus comprises a reaction vessel holding a melt mixture containing an alkali metal and a group III metal in a vessel space thereof, a porous member holding a metal melt by a surface tension thereof in a path through which a vapor of the alkali metal in contact with the metal mixture in the vessel space escapes to an external space, the porous member further supplying a nitrogen source gas fed from outside thereto further to the reaction vessel therethrough and through the metal melt by a pressure difference formed between the vessel space in the reaction vessel and the external space, and a heating apparatus heating the melt mixture to a crystal growth temperature.