| 摘要 |
<p>A method and apparatus for withdrawing a single crystal. In conventional methods of withdrawing a single crystal, a neck having a small diameter is formed in order to eliminate dislocation introduced when a seed crystal is immersed in a melt. When a single crystal having a large diameter of 12 inches or larger and a great weight is to be withdrawn, however, it cannot be supported to cause it to fall. Also, there is involved a problem that dislocation cannot be eliminated and is propagated to a single crystal when the neck is enlarged in diameter in order to prevent falling. The invention uses a single crystal withdrawing apparatus provided with a laser beam generating device or a non-coherent light generating and introducing device such that after irradiation of a laser beam or a non-coherent light to gradually raise a tip end of a seed crystal in temperature, the seed crystal is immersed in a melt to thereby prevent introduction of dislocation in the seed crystal due to thermal stresses, and thereafter a single crystal is withdrawn without formation of any neck. Therefore, a single crystal having a great weight can be withdrawn. The method and apparatus for withdrawing a single crystal, according to the invention, are used in withdrawing a single crystal ingot such as a large-sized silicon single crystal.</p> |
