发明名称 |
METHOD FOR PRODUCING TITANIUM-DOPED SILICA GLASS FOR USE IN EUV LITHOGRAPHY |
摘要 |
The Ti3+ ions present in Ti-doped silica glass cause a brown staining of the glass, causing inspection of the lens to become more difficult. Known methods for reducing Ti3+ ions in favor of Ti4+ ions in Ti-doped silica glass include a sufficiently high proportion of OH-groups and carrying out an oxygen treatment prior to vitrification, which both have disadvantages. In order to provide a cost-efficient production method for Ti-doped silica glass, which at a hydroxyl group content of less than 120 ppm shows an internal transmittance (sample thickness 10 mm) of at least 70% in the wavelength range of 400 nm to 1000 nm, the TiO2—SiO2 soot body is subjected to a conditioning treatment with a nitrogen oxide prior to vitrification. The blank produced in this way from Ti-doped silica glass has the ratio Ti3+/Ti4+≦̸5×10−4. |
申请公布号 |
EP3033306(A1) |
申请公布日期 |
2016.06.22 |
申请号 |
EP20140744804 |
申请日期 |
2014.07.22 |
申请人 |
HERAEUS QUARZGLAS GMBH & CO. KG |
发明人 |
OCHS, STEFAN;BECKER, KLAUS;THOMAS, STEPHAN |
分类号 |
C03B19/14;C03B20/00;C03C3/06 |
主分类号 |
C03B19/14 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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