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:
Apr. 04, 1995
Filed:
Oct. 30, 1992
Burn J Lin, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A phase-shifting mask consisting of phase shifting rim surrounding every pattern. The 0.degree. and 180.degree. areas defined by a straightforward rim phase-shifting mask are reversed alternately for closely packed patterns. This reversal can take the form of 0.degree. to 180.degree. and 180.degree. to 0.degree. as well as the form of 0.degree. to 180.degree. and 0.degree. to -180.degree. . For small opaque lines, the rim phase shifter may become the only picture element, leaving no mask absorber pattern inside the rim. Individual or uniform pattern sizing can be used to ensure a large common exposure-defocus window. Various fabrication techniques requiring or not requiring a second aligned exposure during mask fabrication, combining with several different forms of mask substrate are also described.