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:
May. 04, 1982
Filed:
Jul. 22, 1980
Bernard J Curtis, Gattikon, CH;
RCA Corporation, New York, NY (US);
Abstract
An improved plasma etching apparatus having a light pipe inserted through the chamber wall for coupling light emitted by different chemical species out of the chamber. The light pipe collects the emission directly or after reflection from the coated surface of a substrate. Stabilization of the intensity of the collected emission is indicative of the end point of the etching process. The invention includes a method for detecting the end point of the etching process by monitoring the intensity of light emitted by a component of a gas contained in the chamber which passes out of the chamber through the light pipe. The light may be coupled directly into the light pipe or the light pipe may be so positioned as to detect the emitted light after it is reflected from the surface of the substrate. The intensity of the light is monitored until it stabilizes, indicating that the etching process is complete.