Patent ID: 6372040
Filing Date: 2002-04-16
Classification: C30B,Y10T

Abstract:
A single crystal growing apparatus, comprising a chamber with a quartz crucible disposed therein, a quartz crucible for melting a melt to be used as raw material for a single crystal, a seed crystal lift mechanism for moving a seed crystal up and down above the quartz crucible, and single crystal gripping members arranged movably in upward and downward directions in the chamber, whereby said seed crystal lift mechanism is used to immerse the seed crystal into a melt in the quartz crucible and to pull up the seed crystal, and to form a single crystal neck portion, a portion with larger diameter of single crystal, and a constricted portion under the portion with larger diameter, and a single crystal rod, and said single crystal gripping members are used to pull up the single crystal by gripping the portion with larger diameter from below and to pull up the single crystal after the portion with larger diameter of the single crystal has been formed; andthere is provided means for controlling temperature T (Â° C.) to satisfy the relation: W&lE;âˆ’(4/3)T+1270 where T is temperature of the gripping portion to grip the portion with larger diameter, W (kg) is weight of single crystal engaged with and held by the single crystal gripping members, and T is between 500Â° C. and 800Â° C. under the condition that:a contact member made of a material having Shore hardness of not less than 70, Vickers hardness of not more than 100, and tensile strength of not less than 400 MPa is used on a portion of the single crystal gripping members, which is brought into contact with the lower part of the portion with larger diameter, and minimum diameter of a constricted portion under the portion with larger diameter is set to 12 mm or more.