| 摘要 |
PURPOSE:To produce a crystal having two kinds of different impurity concentrations and low segregation, by inserting a material for crystallization in crucible, adding an impurity into the crucible when the upper part of the material is partially melted, starting the pulling up of the crystal and controlling the amount of the molten liquid in the crucible in a specific manner during the pulling-up process. CONSTITUTION:A solid material 10 for the production of single crystal is inserted into the crucible 3. When a part of the top of the material 10 is melted, an impurity is added to the molten liquid 4, and the pulling up of the single crystal is started. In the course of pulling-up operation, the weight of the molten liquid 4 in the crucible is decreased according to the growth of the crystal 5 in a manner that the ratio of the weight variation of the first grown crystal as a whole to the weight variation of the molten liquid 4 in the crucible 3 is made to coincide with the negative value of the effective segregation coefficient of the impurity relative to the molten liquid 4. The pulling up is stopped, the weight of the molten liquid 4 is increased and the pulling up is restarted. The weight of the molten liquid 4 is decreased according to the growth of the crystal 5 in a manner that the ratio of the weight variation of the second grown crystal as a whole after the restart of pulling-up to the weight variation of the molten liquid 4 is made to coincide with the negative value of said effective segregation coefficient.
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