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:
Aug. 09, 2005
Filed:
Mar. 16, 2004
Lars W. Liebmann, Poughquag, NY (US);
Carlos A. Fonseca, Staten Island, NY (US);
Ioana Graur, Poughkeepsie, NY (US);
Mark A. Lavin, Katonah, NY (US);
Lars W. Liebmann, Poughquag, NY (US);
Carlos A. Fonseca, Staten Island, NY (US);
Ioana Graur, Poughkeepsie, NY (US);
Mark A. Lavin, Katonah, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method is described for designing an alternating phase shifted mask (altPSM) by optimally selecting the width of phase shapes. The selection of optimal phase shape widths is achieved by providing a lithography metric that describes the relationship between phase shape width and the target image dimension such that the metric, such as process window or across chip linewidth variation (ACLV), is optimized. In a preferred embodiment, ACLV is computed by Monte Carlo simulation by providing a set of error distributions for lithographic parameters such as focus, dose, lens aberrations, and the like. Alternatively, a lookup table of optimal phase widths associated with target image dimensions may be provided. The resulting altPSM is characterized by phase shapes having widths that vary according to the widths of the target image dimensions.