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:
Feb. 27, 1979
Filed:
Dec. 19, 1977
Hans P Kleinknecht, Bergdietikon, CH;
James Kane, Zumikon, CH;
RCA Corporation, New York, NY (US);
Abstract
A method of optically monitoring the thickness of a layer of material being deposited on a substrate within a reaction chamber comprises forming on a body a diffraction grating profile, exposing the grating profile to a beam of light while depositing the material on both the substrate and the grating profile, whereby the grating profile functions as a relief pattern diffracting the light beam into diffracted beams of various orders, measuring the intensity of the first order (I.sub.1) and second order (I.sub.2) beams to obtain a ratio signal (I.sub.2 /I.sub.1), and then transmitting the ratio signal to processing means for determining the aspect groove width of the relief pattern, whereby the thickness of the depositing layer is determined from a pre-established relationship dependent upon the aspect groove width.