DEVICE FOR PULLING UP SINGLE CRYSTAL

摘要

A device for pulling up a single crystal produced through the Czochralski process, characterized in that: one side thereof facing the quartz crucible is composed of a heat absorbing body whereas the other a heat insulating body; a first cylindrical screen having at upper and lower ends an outwardly directed annular rim and inwardly directed one, respectively, and also having a corner part which faces said crucible and is formed into a curved or polygonal surface is disposed around a single crystal pulling up area with said annular rim at the lower end positioned near an area in which molten material is filled; and a second screen in the shape of parabola at cross-section to open at the central part while surrounding the single crystal pulling up area, and having an outwardly directed annular rim at the upper end is provided inside said first screen, and, thus, the device intends to quickly pull up a single crystal bar while preventing contamination of crystal otherwise caused by impurities and interruption of single-crystallization. A second screen in such a cross-sectional shape as extending along the first screen may be disposed inside the first screen and the second screen may be provided with a forced cooling mechanism.