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:
Nov. 08, 1994
Filed:
Apr. 23, 1993
Daniel E Glenn, Mountain View, CA (US);
Luxtron Corporation, Santa Clara, CA (US);
Abstract
A detector structure and technique for non-contact monitoring of a process being performed on a surface, such as in semiconductor wafer integrated circuit processing and flat panel display substrate processing, in order to determine when the process has reached endpoint. In one embodiment, multiple small area radiation sources, such as light emitting diodes, are symmetrically arranged around a large area photodetector, and each have similar radiation distribution patterns. In an alternative embodiment, multiple photodetectors are symmetrically arranged around a single light emitting diode with a symmetrical radiation distribution pattern. In either case, the amount of source radiation reflected onto the detector from the surface being processed is not significantly affected by any wobble or tilting of the surface that may occur during processing.