Patent ID: 8061225
Filing Date: 2011-11-22
Classification: C30B,G16C

Abstract:
1. A method for determining a COP generation factor of a single-crystal silicon wafer, wherein a determination area of the wafer is concentrically divided in a radial direction and further divided in a circumferential direction, COP density of each determination segment in the circumferential direction is obtained in each determination segment having an identical radius, a maximum value in the determination segment having the identical radius is set at COP density CIRCUMFERENCEMAX , a minimum value is set at COP density CIRCUMFERENCEMIN , and a determination that the COP generation factor is attributed to a factor except for a defect induced during crystal growth is made when a value computed by “(COP density CIRCUMFERENCEMAX −COP density CIRCUMFERENCEMIN )/COP density CIRCUMFERENCEMAX ” is not less than a predetermined setting value.