METHOD FOR MEASURING DISTANCE BETWEEN REFERENCE REFLECTOR AND MELT SURFACE

摘要

The present invention is a method for determining a relative distance between a reference member placed above a melt surface and the melt surface upon pulling a silicon single crystal out of a raw material melt in a crucible by a CZ method characterized by at least: pulling the silicon single crystal applying a magnetic field; taking a picture of a real image of the reference member and a mirror image of the reference member reflected on the melt surface with a detector; processing the picture taken of the real image and the mirror image of the reference member as different pictures by separating the picture taken; and calculating the relative distance between the real image and the mirror image of the reference member from the processed pictures to determine the relative distance between the reference member and the melt surface. This provides a method for determining the distance between the reference member and the melt surface that makes it possible to determine the relative distance between the reference member and the melt surface more stably and more accurately.