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

摘要

A nitride semiconductor wafer is planar-processed by grinding a bottom surface of the wafer, etching the bottom surface by, e.g., KOH for removing a bottom process-induced degradation layer, chamfering by a rubber whetstone bonded with 100wt%-60wt% #3000-#600 diamond granules and 0wt%-40wt% oxide granules, grinding and polishing a top surface of the wafer, etching the top surface for eliminating a top process-induced degradation layer and maintaining a 0.5µm-10µm thick edge process-induced degradation layer.