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. 15, 1982
Filed:
May. 12, 1980
Justin L Kreuzer, Trumbull, CT (US);
David H Kittell, Stamford, CT (US);
The Perkin-Elmer Corporation, Norwalk, CT (US);
Abstract
There are disclosed method and apparatus for precisely aligning the pattern of an opaque mask with a previously exposed pattern on a silicon wafer. Three separate optical channels are aligned so that their axes coincide with three targets on the wafer. The objectives are also adjusted to the same vertical distance from the wafer. Thereafter, the optical channels remain fixed. The wafer is retracted a short distance and is replaced by the mask which also has three targets. The mask is then shifted to align the targets with the prealigned optical axes. When mask alignment is completed, the mask and the wafer are removed as a unit to an exposure station.