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. 24, 1996
Filed:
Jun. 05, 1995
Anthony Sayka, San Antonio, TX (US);
Patricia A Vargas, Cheaspeake Beach, MD (US);
VLSI Technology, Inc., San Jose, CA (US);
Abstract
A coating method for detecting the presence of contaminants carried by a liquid that is applied as a coating on a workpiece. A tube guides the liquid along a flow path to the workpiece. A light source illuminates the liquid along the flow path with an optical fiber or other light carrier, and light is scattered by any contaminants present in the liquid. Light scattered by the contaminant particles is more intense than light scattered by the other liquid particles, and this brighter scattered light is detected by a light detector positioned adjacent to the fluid flow path. The coating system is particularly well suited for use in a spin-on coating process that applies a liquid, such as a photoresist material or a dielectric material, to a semiconductor wafer or other workpiece that is secured to a rotating turntable and rotated to receive a coating of the liquid.