Vitreous silica crucible and evaluation method of the same
Abstract:
A vitreous silica crucible used to pull up silicon single crystal includes: a cylindrical straight body portion, a corner portion formed at a lower end of the straight body portion, and a bottom portion connected with the straight body portion via the corner portion, wherein the vitreous silica crucible further comprises: an opaque outer layer enclosing bubbles therein; and a transparent inner layer from which bubbles are removed, wherein the residual distortion's distribution obtained by measuring the silica glass's inner surface in a non-destructed state has an optical path difference which is 130 nm or less, which residual distortion's distribution is measured using a distortion-measuring apparatus which converts a linearly polarized light into circularly polarized light and then irradiates the crucible's wall.
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