SAPPHIRE SUBSTRATE POLISHING METHOD AND SAPPHIRE SUBSTRATE OBTAINED

摘要

PROBLEM TO BE SOLVED: To provide a sapphire substrate polishing method which can control a warpage shape of a sapphire substrate for epitaxial growth, which is used for a light emitting diode; and provide a sapphire substrate obtained.SOLUTION: A double-sided polishing method of a sapphire substrate comprises: a first process of performing lapping on both surfaces of a substrate 4 by a double-ended lapping device having a lower surface plate 1 and an upper surface plate 2; a second process of mirror polishing both surfaces; and a third process of performing single-side polishing only on a first surface to make a strained layer of a second surface become thicker than that of the first surface.SELECTED DRAWING: Figure 1