Quartz glass crucible, manufacturing method therefor, and method for manufacturing silicon single crystal
AssigneeSumco Corporation
InventorsEriko Kitahara, Hiroshi Kishi, Hideki Fujiwara
Life of this patent
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Abstract
A quartz glass crucible has, from an inner surface side toward an outer surface side of the crucible, an inner transparent layer, a bubble layer, an outer transparent layer, and a crystallization accelerator-containing layer. An outer transition layer where a bubble content decreases from the bubble layer toward the outer transparent layer is provided at a boundary between the bubble layer and the outer transparent layer, and a thickness of the outer transition layer is 0.1 mm or more and 8 mm or less.
Claims6
A quartz glass crucible for pulling a silicon single crystal, the quartz glass crucible comprising:
- a crucible main body made of silica glass;
- and
- a crystallization accelerator-containing layer provided on an outer surface of the crucible main body,
- wherein the crucible main body includes, from an inner surface side toward an outer surface side of the crucible, an inner transparent layer containing no bubbles, a bubble layer containing bubbles and provided outside of the inner transparent layer, and an outer transparent layer provided outside of the bubble layer,
- an outer transition layer where a bubble content decreases from the bubble layer toward the outer transparent layer is provided at a boundary between the outer transparent layer and the bubble layer,
- a thickness of the outer transition layer is 0.1 mm or more and 8 mm or less,
- a bubble content of the bubble layer is 1 to 4 vol %,
- a bubble content of the outer transparent layer is 0.1 vol % or less,
- in a case where an average bubble content of the outer transparent layer is 0 and an average bubble content of the bubble layer is 1, an average bubble content of the outer transition layer is from 0.1 to 0.7,
- the crystallization accelerator-containing layer contains a crystallization accelerator, and
- the crystallization accelerator-containing layer is a layer applied to the outer surface of the crucible main body and formed directly on an outside of the outer transparent layer.
Dependencies are inferred from the claim text.