Method for growing silicon single crystal

Abstract

A method for growing silicon single crystal by the CZ method, namely by feeding silicon materials for crystal into a crucible to melt the materials, and growing a silicon single crystal on the lower end of the seed crystal, comprises: forming a narrowingly tapered portion with a gradually decreased seed crystal diameter by pulling up the seed crystal inserted in the melt; and providing increased or decreased neck diameter regions in the process of forming a neck in such a manner that each increased neck diameter is provided by increasing the neck diameter, followed by reverting the neck diameter to the original diameter, or alternatively, each decreased neck diameter region is provided by decreasing the neck diameter, followed by reverting the diameter to the original diameter, thereby enabling to reliably eliminate dislocations remaining in the central axial region of the neck in the step of necking. When the neck diameter is increased or decreased at the final stage in the process of forming the neck, dislocations can be eliminated more efficiently.

Dependencies are inferred from the claim text.