METHOD FOR MACHINING NITRIDE SEMICONDUCTOR WAFER, NITRIDE SEMICONDUCTOR WAFER, PROCESS FOR PRODUCING NITRIDE SEMICONDUCTOR DEVICE, AND NITRIDE SEMICONDUCTOR DEVICE

摘要

Disclosed is a method for machining a nitride semiconductor wafer that, when a nitride semiconductor crystal is subjected to back grinding, outer periphery grinding (chamfer), and surface grinding/polishing to produce a mirror wafer, causes no significant warpage, is free from cracking, and can realize a high substrate production process yield, and a high device in-plane yield. The outer peripheral part of a nitride semiconductor wafer is chamfered with a rubber grinding stone or a resin foam bonded grinding stone comprising 0 to 40% by weight of oxide abrasive grains to allow a work affected layer having a thickness of 0.5 µm to 10 µm to stay on the outer peripheral part.