CPC C30B 15/10 (2013.01) [C03B 20/00 (2013.01); C03C 19/00 (2013.01); C30B 29/06 (2013.01); F27B 14/10 (2013.01); G01N 21/3563 (2013.01); G01N 33/386 (2013.01); C03B 19/095 (2013.01)] | 7 Claims |
1. A quartz glass crucible comprising:
a cylindrical side wall portion;
a bottom portion; and
a corner portion connecting the side wall portion and the bottom portion to each other;
wherein the cylindrical side wall portion, the bottom portion, and the corner portion are constituted by:
a transparent layer made of quartz glass that does not contain bubbles;
a bubble layer formed outside the transparent layer and made of quartz glass containing bubbles; and
a semi-molten layer formed outside the bubble layer and made of raw material silica powder solidified in a semi-molten state,
wherein the transparent layer and the bubble layer in the corner portion constitute a first laminate having a first infrared transmissivity which is 25 to 51% in a thickness direction,
the transparent layer and the bubble layer in the side wall portion constitute a second laminate having a second infrared transmissivity which is 46 to 84% in a thickness direction and which is higher than the first infrared transmissivity, and
the transparent layer and the bubble layer in the bottom portion constitute a third laminate having a third infrared transmissivity which is 36 to 70% in a thickness direction and which is higher than the first infrared transmissivity, and
wherein the bubble layer in the side wall portion has a thickness which is greater than a thickness of the transparent layer in the side wall portion, and
the bubble layer in the corner portion has a thickness which is greater than the thickness of transparent layer in the side wall portion.
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