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. 17, 1984
Filed:
May. 18, 1981
Applicant:
Inventors:
Karl-Heinz Johannsmeier, Los Altos, CA (US);
Edward H Phillips, Middletown, CA (US);
Assignee:
Optimetrix Corporation, Mountain View, CA (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
355 53 ; 356390 ; 356394 ;
Abstract
A device is disclosed for use on a projection type semiconductive wafer precision step-and-repeat alignment and exposure system for on-machine inspection of a reticle containing the circuitry to be printed on the wafer. Two apertured optical detectors are aligned with identical portions of the projected image of the reticle and scanned across the image of the reticle. Any difference in the electrical response of the two optical detectors indicates dirt or a flaw in the reticle.