| 摘要 |
PROBLEM TO BE SOLVED: To obtain a heavyweight single crystal by using a silicon seed crystal with the oxygen concentration controlled within a specified range to effectively exclude introduction of dislocations in the beginning of single crystal formation and also exclude neck formation so as to prevent the single crystal being pulled-up from falling. SOLUTION: This seed crystal for pulling up a single crystal consists of silicon with an oxygen concentration of 12 to 18×10<17> /cm. In the pulling-up of signals crystal, the diameter (l) of the seed crystal 15 is set at >=6mm; after preheating its tip 15a, the seed crystal is dipped into a silicon melt 33, melted, and a shoulder 16b is formed without necking; subsequently, the main body is formed, and the resultant single crystal is pulled-up. In the above process, the length L of the tip 15a to be dipped into the melt 33 and to be melted is at least the diameter (l) of the seed crystal 15.
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