Manner null of the monocrystal pulling up which uses the silicon seed crystal and the said silicon seed crystal for monocrystal pulling up

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 18×10¹⁷/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.;COPYRIGHT: (C)1997,JPO