METHOD FOR DETERMINING THREE-DIMENSIONAL DISTRIBUTION OF BUBBLE DISTRIBUTION IN SILICA GLASS CRUCIBLE AND METHOD FOR MANUFACTURING SILICON SINGLE CRYSTAL

摘要

PROBLEM TO BE SOLVED: To provide a method for determining a three-dimensional distribution of bubble distribution in a silica glass crucible with high accuracy.SOLUTION: A method for determining a three-dimensional distribution of bubble distribution in a silica glass crucible comprises the steps of: moving an internal range-finding part 17 in a noncontact manner along an inner surface of a silica glass crucible that has a transparent silica glass layer 13 on an inner surface side and a bubble-containing silica glass layer 15 on an outer surface side; irradiating the inner surface of the silica glass crucible obliquely thereto with a laser beam from the internal range-finding part in multiple measurement points on a movement path, and, while varying a distance between the internal range-finding part and the inner surface and a laser beam emission direction so as to be able to observe two peaks by measuring reflection light of the laser beam using a laser displacement meter, measuring the inner surface distance between the internal range-finding part and the inner surface by a peak position on the inner surface side out of the two peaks and measuring an interface distance between the internal range-finding part and an interface by a peak position on the outer surface side out of the two peaks; calculating a three-dimensional shape of the inner surface of the silica glass crucible; and determining a three-dimensional distribution of bubble distribution of a crucible wall at a position corresponding to each of the measurement points.SELECTED DRAWING: Figure 2