GROUP IIIB NITRIDE CRYSTAL MANUFACTURING METHOD

摘要

A seed crystal substrate is prepared by forming a gallium nitride thin film on a surface of a sapphire substrate, and is placed inside a growing container (12). In addition, metallic gallium and metallic sodium are weighed out such that their molar ratio is 25-32:68-75 and are placed inside the growing container (12). The growing container (12) is placed inside a reaction container (20), an inlet pipe (22) is connected to the reaction container (20), and the reaction container (20) is filled with nitrogen gas from a nitrogen gas tank (42) via a pressure regulator (40). Then the system is regulated until a specific nitrogen gas pressure is achieved inside the reaction container (20), and target temperatures are set such that the temperature of a lower heater (46) is higher than that of an upper heater (44), and a gallium nitride crystal is grown. As a result, a flow in the molten mixture inside the growing container (12) is created in the direction along the surface of the seed crystal substrate due to thermal convection.