AlN HETEROEPITAXIAL CRYSTAL, METHOD FOR PRODUCING THE SAME, BASE SUBSTRATE FOR GROUP III NITRIDE FILM USING THE CRYSTAL, LIGHT-EMITTING DEVICE, SURFACE ACOUSTIC WAVE DEVICE, AND SPUTTERING APPARATUS

摘要

Disclosed is a method for producing a highly crystalline high-quality AlN heteroepitaxial crystal by sputtering. Specifically, after exposing the surface of a sapphire substrate to a plasma using a nitrogen gas or a mixed gas of a nitrogen gas and a rare gas, a reactive sputtering is performed using a nitrogen gas or a mixed gas of a nitrogen gas and a rare gas, while maintaining vacuum, so that AlN is heteroepitaxially grown on the surface of the sapphire substrate.