| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for pulling a single crystal, by which a long single crystal having constant specific resistance is efficiently grown. SOLUTION: In the method for pulling a single crystal, when the impurity concentration in a melt 4 exceeds an upper limit value, a seed crystal part 7 is formed at the lower end of a single crystal 5 being pulled, and then, the growth of the single crystal 5 is stopped once. A raw material is replenished into a crucible 3 during stoppage, and when the impurity concentration in the melt 4 falls below a lower limit value, the growth of the single crystal 5 is restarted by using the seed crystal part 7 (without attaching a new seed crystal 2). Steps of forming a seed crystal part 7, stopping once growing of the single crystal 5, replenishing the raw material, and restarting of growing the seed crystal 5 are performed repeatedly. When the growth of the single crystal 5 is stopped once, the impurity concentration in the melt 4 is uniformized and the disturbance of the surface 4a of the melt 4 is depressed. COPYRIGHT: (C)2011,JPO&INPIT
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