The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 06, 2009
Filed:
Oct. 06, 2006
Masayuki Shiraishi, Kumagaya, JP;
Masayuki Shiraishi, Kumagaya, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Multilayer-film (MLF) reflective mirrors are disclosed that have a highly precise surface profile. An exemplary MLF reflective mirror includes multilayer film in which layers of molybdenum (Mo) and layers of silicon (Si) are periodically deposited in an alternating manner on the surface of a mirror substrate. One or more selected regions of the multilayer film have been 'shaved' away layer-wise as required to impart an in-plane distribution of removed material sufficient to correct a wavefront error in light reflected from the mirror. After such 'layer-machining,' a single-layer film of Si (or Si-containing material) is applied to fill in the machined areas and restore the original contour, as designed, for the surface of the multilayer film. I.e., the Si film has a thickness distribution corresponding to the depth profile of material removed from the multilayer film. A capping layer can be deposited uniformly on the surface of the single-layer film.