Reduction objective for extreme ultraviolet lithography
AssigneeCarl-Zeiss-Stiftung
InventorUdo Dinger
Life of this patent
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Abstract
A reduction objective, a projection exposure apparatus with a reduction objective, and a method of use thereof are disclosed. The reduction objective comprises four (primary, secondary, tertiary, and quaternary) mirrors in centered arrangement with respect to an optical axis. The primary mirror is a convex mirror and the second mirror has a positive angular magnification. The reduction objective has an obscuration-free light path and is suitable for annular field scanning operation, such as is used in soft X-ray, i.e. and EUV and UV, lithography.
Claims19
A reduction objective, with an image side and an object side, comprising:
- a primary multilayer mirror, a secondary multilayer mirror, a tertiary multilayer mirror and a quaternary multilayer mirror in centered arrangement with respect to an optical axis situated between the image side and the object side, wherein the primary mirror is convex and the secondary mirror has positive chief ray angular magnification.
A projection exposure apparatus including a reduction objective, with an image side and an object side, for annular field scanning operation, comprising:
- a mask;
- and
- a primary multilayer mirror, a secondary multilayer mirror, a tertiary multilayer mirror and a quaternary multilayer mirror in centered arrangement with respect to an optical axis situated between the image side and the object side, wherein the primary mirror is convex and the secondary mirror has a positive chief ray angular magnification.
A method for integrated circuit fabrication using a projection exposure apparatus including a reduction objective, with an image side and an object side, including the steps of:
- providing a mask;
- and
- providing a primary multilayer mirror, a secondary multilayer mirror, a tertiary multilayer mirror and a quaternary multilayer mirror in centered arrangement with respect to an optical axis situated between the image side and the object side, wherein the primary mirror is convex and the secondary mirror has a positive chief ray angular magnification.
Dependencies are inferred from the claim text.