发明名称 |
Projection objective, especially for microlithography, and method for adjusting a projection objective |
摘要 |
A method of adjusting a projection objective permits the projection objective to be adjusted between an immersion configuration and a dry configuration with few interventions in the system, and therefore to be used optionally as an immersion objective or as a dry objective. The projection objective has a multiplicity of optical elements which are arranged along an optical axis of the projection objective, the optical elements comprising a first group of optical elements following the object plane and a last optical element following the first group, arranged next to the image plane and defining an exit surface of the projection objective which is arranged at a working distance from the image plane. The last optical element is substantially without refracting power and has no curvature or only slight curvature. The method comprises varying the thickness of the last optical element, changing the refractive index of the space between the exit surface and the image plane by introducing or removing an immersion medium, and preferably axial displacement of the last optical element in order to set a suitable working distance.
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申请公布号 |
US2007188881(A1) |
申请公布日期 |
2007.08.16 |
申请号 |
US20070783966 |
申请日期 |
2007.04.13 |
申请人 |
CARL ZEISS SMT AG |
发明人 |
EPPLE ALEXANDER;GRAEUPNER PAUL;KAISER WINFRIED;GARREIS REINER;ULRICH WILHELM |
分类号 |
G02B3/00;G02B13/24;G02B13/00;G03F7/20;H01L21/027 |
主分类号 |
G02B3/00 |
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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