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:
Jun. 12, 2001
Filed:
Apr. 16, 1999
Martin Feldman, Baton Rouge, LA (US);
Board of Supervisors of Louisiana State University and Agricultural and Mechanical College, Baton Rouge, LA (US);
Abstract
A scanning microscope is disclosed that uses an optical phase shift technique for high optical resolution, without reducing either the depth of focus or the working distance. The technique minimizes, for example, error in the location of edges of features on lithographic masks or wafers. The technique also permits the accurate determination of edges on features that would otherwise be too narrow to be measured. The microscope is useful in any field where optical microscopes are employed, including for example both semiconductor and biological applications. It is also useful in optical data storage applications. In addition, a small numerical aperture in the optical system allows a high depth of focus, while maintaining the resolution. The microscopes use standard components to produce high intensity images with large working distances and large depths of focus, without substantial mechanical complexity.