| 摘要 |
PROBLEM TO BE SOLVED: To provide a silica glass crucible which is excellent in deformation resistance and also excellent from the viewpoint of cost, and which provides the sample thereof formed from a synthetic silica raw material in which a layer formed from a natural silica raw material does not coexist and which hence provides exact result of measurement of impurity concentration, and to provide a method for producing the same. SOLUTION: The silica glass crucible is provided with an opening part area 2c having predetermined lengths in the depth direction and the circumferential direction from the upper end of the opening and a side-bottom surface part areas 2a, 2b ranging from the opening part area 2c to the bottom part of the crucible. In the opening part area 2c and the side-bottom surface part area 2a, 2b, the silica glass crucible has a constant thicknesses (t1+t2=t3+t4). In the opening part area 2c, a thickness t3 part having a thickness of at least 2 mm from inner surface is formed from a synthetic silica raw material, and the remaining thickness t4 part is formed from a natural silica raw material. In the side-bottom surface part area 2a, 2b, a thickness t1 part having a thickness of at least 0.5-1.5 mm from the inner surface is formed from the synthetic silica raw material, and the remaining thickness t2 part is formed from the natural silica raw material. COPYRIGHT: (C)2008,JPO&INPIT
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