Method of manufacturing silicon single crystal, silicon single crystal and silicon wafer

Abstract

The present invention is a method of manufacturing a silicon single crystal by Czochralski method without performing Dash Necking method, comprising the steps of: providing a seed crystal having a tip end with a sharp-pointed shape or a truncation thereof in which an angle of the tip end is 28° or less; keeping the tip end of the seed crystal at just above a silicon melt to heat it before bringing the tip end of the seed crystal into contact with the silicon melt; bringing the tip end of the seed crystal into contact with the silicon melt and immersing the seed crystal into the silicon melt to a desired diameter; and shifting to pull the single crystal, wherein a temperature variation at a surface of the silicon melt is kept at ±5° C. or less at least for a period from a point of bringing the tip end of the seed crystal into contact with the silicon melt to a point of shifting to pull the single crystal. Thereby, in a method of growing a silicon single crystal by Czochralski method without using Dash Necking method, a success ratio of growing a single crystal free from dislocation can be increased, at the same time a heavy silicon single crystal having a large diameter in which a diameter of a constant diameter portion is over 200 mm can be grown even in the case of growing a silicon single crystal having a crystal orientation of <110>.

1 . A silicon single crystal grown by Czochralski method without performing Dash Necking method, which has a crystal orientation of <110>, and a constant diameter portion with a diameter of 200 mm or more.  
   
   
       2 . The silicon single crystal according to  claim 1 , wherein total weight of the single crystal pulled from the silicon melt is 100 kg or more.  
   
   
       3 . A silicon wafer, wherein a main diameter of the wafer is 200 mm or more, and a plane orientation of a main surface of the wafer is (110).