| US 7,587,912 B2 | ||
| Method for producing quartz glass crucible for use in pulling silicon single crystal and quartz glass crucible produced by said method | ||
| Yasuo Ohama, Takefu (Japan); and Hiroshi Matsui, Takefu (Japan) | ||
| Assigned to Heraeus Quarzglas GmbH & Co. KG, Hanau (Germany); and Shin-Etsu Quartz Products Co., Ltd., Tokyo (Japan) | ||
| Appl. No. 10/547,053 PCT Filed Feb. 20, 2004, PCT No. PCT/EP2004/001663 § 371(c)(1), (2), (4) Date Aug. 24, 2005, PCT Pub. No. WO2004/076725, PCT Pub. Date Sep. 10, 2004. |
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| Claims priority of application No. 2003-052704 (JP), filed on Feb. 28, 2003. | ||
| Prior Publication US 2006/0174651 A1, Aug. 10, 2006 | ||
| Int. Cl. C03B 19/09 (2006.01) | ||
| U.S. Cl. 65—17.3 | 4 Claims |
| 1. A method for producing a quartz glass crucible for use in pulling silicon single crystal, said method comprising:
forming said quartz glass crucible so as to have at least a double-layer structure comprising a pore-free transparent inner
layer and an opaque base body having pores therein, including forming at least the base body of the crucible with a silica
powder, wherein, prior to said forming the base body, the silica powder is maintained in a storage hopper in a gas having
a humidity mixing ratio of 0.0005 to 0.0065 kg/kg (dry gas) and kept at a temperature of −5° C. to +18° C. so as to prevent
absorption of moisture by the silica powder.
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