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:
Sep. 04, 2007
Filed:
Mar. 11, 2004
Toshiharu Furukawa, Essex Junction, VT (US);
Mark Charles Hakey, Fairfax, VT (US);
Steven John Holmes, Guilderland, NY (US);
David Vaclav Horak, Essex Junction, VT (US);
Charles William Koburger, Iii, Delmar, NY (US);
Peter H. Mitchell, Jericho, VT (US);
Larry Alan Nesbit, Williston, VT (US);
Toshiharu Furukawa, Essex Junction, VT (US);
Mark Charles Hakey, Fairfax, VT (US);
Steven John Holmes, Guilderland, NY (US);
David Vaclav Horak, Essex Junction, VT (US);
Charles William Koburger, III, Delmar, NY (US);
Peter H. Mitchell, Jericho, VT (US);
Larry Alan Nesbit, Williston, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Methods for fabricating alternating phase shift masks or reticles used in semiconductor optical lithography systems. The methods generally include forming a layer of phase shift mask material on a handle substrate and patterning the layer to define recessed phase shift windows. The patterned layer is transferred from the handle wafer to a mask blank. The depth of the phase shift windows is determined by the thickness of the layer of phase shift mask material and is independent of the patterning process. In particular, the depth of the phase shift windows is not dependent upon the etch rate uniformity of an etch process across a surface of a mask blank.