[P-11] High-Resolution X-Ray Diffraction Measurement of Sapphire Substrate for Detection of Subsurface Damages 〇Hideo Aida1, Ryo Yoshihara1, Hidetoshi Takeda1, Yutaka Kimura2, Toshiro Doi3 (1.Nagaoka University of Technology, 2.Aoyama Gakuin University, 3.Kyushu University/Doi Laboratory Inc.) Keywords:Polishing、Sapphire substrate、Subsurface damage、Chemical mechanical polishing (CMP)、X-ray diffraction (XRD)