| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique which contributes the stable production of a single crystal silicon by selecting a polycrystal silicon suitable for a production raw material for the single crystal silicon in high quantitativity and reproducibility.SOLUTION: When evaluating a grain size of a polycrystal silicon by an X-ray diffraction method, a value (&Dgr;B/P) is used as an evaluation index of the grain size of the polycrystal silicon by the steps of: placing a sampled tabular specimen 20 at a position where Bragg reflection from a Miller index plane <hkl> is detected; rotating the tabular specimen 20 in a plane around the center of the tabular specimen 20 as a rotation center by a rotation angle of &phgr; so that an X-ray irradiation region defined by a slit &phgr;-scans on a principal surface of the tabular specimen 20; obtaining a chart indicating rotation angle (&phgr;) dependency of a Bragg reflection intensity of the tabular specimen 20 from the Miller index plane <hkl>; obtaining a difference (&Dgr;B) between a maximum value (B) and a minimum value (B) of a diffraction intensity value of a base line from the chart; and dividing &Dgr;B by a mean value (P) of the diffraction intensity values. |
