论文信息 - Fabrication of an aspherical mirror for extreme-ultraviolet lithography (EUVL) optics

Fabrication of an aspherical mirror for extreme-ultraviolet lithography (EUVL) optics

We report a progress in the aspherization of precision of optical surface by deposition of graded-thickness films onto spherical substrate. As a deposition film, we examined single layer and multilayer film. Mo/Si multilayer had small stress and small surface roughness up to the total film thickness of 1 micrometers , and is suitable for the thin film to fabricate mirrors in the EUVL camera. We demonstrate an aspherical mirror fabrication using mask deposition technique. The result shows good agreement between the measured and desired thickness profiles.

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