SINGLE CRYSTAL PULLING-UP EQUIPMENT AND SINGLE CRYSTAL PULLING-UP METHOD USING THE SAME

摘要

PROBLEM TO BE SOLVED: To inhibit the thermal stress from being caused in the single crystal by uniformizing the temp. gradient in the vicinity of the solid-liquid interface, along the axial direction of a central part of a silicon single crystal bar being pulled up from a silicon melt. SOLUTION: This equipment is provided with: a heat-shield member 26 having a heat-radiation inhibition section 26c which is formed in the lower part of the member 26 and has a downwardly tapered conical shape so that the opening diameter of the section 26c is gradually and downwardly decreased; plural heat radiation plates 27 which are placed on the heat-radiation inhibition section 26c so that a single crystal bar 25 is surrounded by the heat radiation plates 27, and the outer periphery of each of which is pivotally supported by the heat-shield member 26; and a heat radiation plate rotation means 41 for rotating each of the plural heat radiation plates 27 to change the angle between the heat radiation plate 27 and the heat-radiation inhibition section 26c; wherein at the time of forming a shoulder 25b of the single crystal bar 25, each of the plural heat radiation plates 27 is erected on the heat-radiation inhibition section 26c at a position being apart from the shoulder 25b and when forming a body 25c of the single crystal bar 25, each of the plural heat radiators 27 is rotated so as to be laid down on the heat-radiation inhibition section 26c.