METHOD FOR MEASURING AND CONTROLLING DISTANCE BETWEEN LOWER END SURFACE OF HEAT SHIELDING MEMBER AND SURFACE OF RAW MATERIAL MELT AND METHOD FOR MANUFACTURING SILICON SINGLE CRYSTAL

摘要

A method for measuring a distance between a lower end surface of a heat shielding member including a criterion reflector inside a concavity on the lower end surface and a surface of a raw material melt includes: a silicon single crystal is pulled by the Czochralski method while a magnetic field is applied to the raw material melt in a crucible, measuring the distance between the lower end surface of the heat shielding member and the surface of the raw material melt and observing a position of a mirror image of the criterion reflector with a fixed point observation apparatus; and measuring a movement distance of the mirror image with the apparatus and calculating the distance between the lower end surface of the heat shielding member and the surface of the raw material melt from the movement distance of the image and the measured distance.