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:
Dec. 22, 1998
Filed:
Jul. 24, 1997
Masato Shibuya, Ohmiya, JP;
Hiroshi Ooki, Yokohama, JP;
Kazuya Okamoto, Yokohama, JP;
Soichi Owa, Tokyo, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Methods and apparatus are disclosed for microlithographically exposing a photosensitive substrate comprising single-exposure areas and multiple-exposure areas. After exposing the substrate, line widths in the single-exposure areas are substantially the same as line widths in the multiple-exposure areas. Also disclosed are masks comprising a first mask pattern used to expose the single-exposure areas once and a plurality of other mask patterns for exposing the multiple-exposure areas a predetermined number of times. Each of the other mask patterns allows a lower intensity of illumination light flux to be distributed to the multiple-exposure areas per exposure of the substrate than allowed by the first mask pattern. Consequently, the average intensity of illumination-light flux distributed to the single-exposure area after one exposure is substantially equal to the average intensity of illumination-light flux distributed to the multiple-exposure areas after a predetermined number of exposures of such areas.