COMPOUND GaN SUBSTRATE AND METHOD FOR PRODUCING SAME, AND GROUP III NITRIDE SEMICONDUCTOR DEVICE AND METHOD FOR PRODUCING SAME

摘要

This compound GaN substrate (1) includes: a conductive GaN substrate (10) of specific resistance of less than 1 ?cm; and, disposed over the conductive GaN substrate (10), a semi-insulating GaN layer (20) of specific resistance of 1×104 ?cm or greater and thickness of 5 µm or greater. This Group III nitride semiconductor device (2) includes the aforementioned compound GaN substrate (1), and at least one Group III nitride semiconductor layer (30) disposed over the semi-insulating GaN layer (20) of the compound GaN substrate (1). A compound GaN substrate (1) and a semiconductor device (2) having advanced characteristics and affordable cost are obtained thereby.