| 摘要 |
<p>Provided is a vitreous silica crucible which can restrain inward collapse deformation at high temperature during pulling even when the crucible has a large opening diameter. The vitreous silica crucible has an outer layer made of natural fused silica and an inner layer made of synthetic fused silica. The straight body section is outwardly-widened upwardly. Preferably, the difference in inner diameter of the lower and upper ends of the outwardly-widened section is 0.1 % or more. The inner layer made of synthetic fused silica on the corner section has a layer thickness which is 20 % to 80 % of the wall thickness of the central portion of the corner section. Preferably, the inner layer made of synthetic fused silica on the straight body section and the bottom section is thinner than that on the corner section.</p> |
