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. 02, 1986
Filed:
Aug. 30, 1985
Gerard Samuels, Paoli, PA (US);
RCA Corporation, Princeton, NJ (US);
Abstract
Defocusing effects by undesired wafer tilt caused by photoresist debris in prior art photolithographic apparatus are substantially eliminated by a novel plate for supporting a wafer to be imaged without generating debris. Three tabs are provided along the periphery of an aperture in the plate. Each tab is provided with a spherical body, such as a ball, precisely positioned in a predetermined plane, and arranged to contact the wafer at a tangent to the surface of the spherical body. Relative movement while loading the wafer in the apparatus with respect to the supporting balls causes substantially no discernible debris from the wafer surface material. Imaging defects on the wafer due to photoresist debris are also substantially eliminated by the apparatus.