Single crystal growth apparatus and single crystal growth method

The present invention relates to a single crystal growing apparatus and a single crystal growing method for manufacturing dislocation-free single crystal of silicon by the pulling CZ (Czochralski) method. In an arrangement to grip lower part of a portion with larger diameter of single crystal formed by CZ method, the present invention provides an apparatus and a method for growing and pulling up the single crystal without causing deformation or rupture and under dislocation-free and stable condition even when the portion with larger diameter is at high temperature and when the single crystal rod has heavy weight of about 400 kg and large diameter. Under the condition that 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 as a contact member which is used on a portion of gripping members in contact with lower part of the portion with larger diameter, and when minimum diameter of a constricted portion under the portion with larger diameter is set to 12 mm or more, temperature (° C.) is controlled to satisfy the relation:where W (kg) is the weight of the single crystal engaged and held, and T (° C.) is temperature of gripping part of the portion with larger diameter, and the temperature T is between 500° C. and 800° C. so that the portion with larger diameter of the single crystal can be gripped under the condition of high temperature and heavy weight.