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:
Mar. 02, 1993
Filed:
Sep. 05, 1990
Applicant:
Inventors:
Steven C Leach, Santa Clara, CA (US);
Jewett W Fowler, Mountain View, CA (US);
Herbert E Litvak, Palo Alto, CA (US);
Mariste A Thomson, Santa Clara, CA (US);
Assignee:
Luxtron Corporation, Santa Clara, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
H01L / ; G01B / ;
U.S. Cl.
CPC ...
156626 ; 156668 ; 156345 ; 20419233 ; 20429832 ; 356357 ;
Abstract
Methods and apparatus for enhancing the accuracy for detecting the endpoint of certain operations (such as etching, photoresist development or chemical reaction) in the processing of materials which results in a change in the reflectivity or refractive index of the material are provided. The methods decrease the sensitivity of endpoint detection to high frequency noise and periodic oscillations. The methods also allow accurate calculation of overprocessing time and real-time viewing of data by the user.