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. 27, 1977
Filed:
Sep. 27, 1976
Applicant:
Inventors:
John David Cuthbert, Bethlehem, PA (US);
David Farnham Munro, Alburtis, PA (US);
Assignee:
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B / ; G01B / ; G01N / ;
U.S. Cl.
CPC ...
356156 ; 356157 ; 356204 ;
Abstract
Very rapid and accurate linewidth measurements in selected subregions of an LSI mask or wafer are made by means of a low-cost apparatus. The apparatus embodies the recognition that an accurate linewidth determination can be made for any particular feature among a variety of features in a repeated array by a calibrated and normalized measurement of the average light transmission or reflection of a subregion that includes the feature. In turn, the measurement is automatically converted to a linewidth reading by analog computing circuitry.