High surface quality GaN wafer and method of fabricating same

摘要

Al_xGa_yIn_zN, wherein 0<=x<=1, 0<=y<=1, 0<=z<=1, and x+y+z=1, characterized by a root mean square surface roughness of less than 1 nm in a 10x10 mum² area. The Al_xGa_yIn_zN may be in the form of a wafer, which is chemically mechanically polished (CMP) using a CMP slurry comprising abrasive particles, such as silica or alumina, and an acid or a base. High quality Al_xGa_yIn_zN wafers can be fabricated by steps including lapping, mechanical polishing, and reducing internal stress of said wafer by thermal annealing or chemical etching for further enhancement of its surface quality. CMP processing may be usefully employed to highlight crystal defects of an Al_xGa_yIn_zN wafer.