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. 20, 1990
Filed:
Oct. 28, 1988
Applicant:
Inventors:
Stephen W Downey, Chatham, NJ (US);
Richard A Gottscho, Maplewood, NJ (US);
Assignee:
AT&T Bell Laboratories, Murray Hill, NJ (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ; H01L / ; B44C / ;
U.S. Cl.
CPC ...
437-7 ; 437228 ; 437-7 ; 437-8 ; 437225 ; 148D / ; 156625 ; 156626 ; 156627 ;
Abstract
Gas phase processes such as plasma etching of a semiconductor substrate is monitored by utilizing the optogalvanic effect. The substrate is subjected to light and in response emits an electron current whose magnitude is representative of the composition at the surface of the substrate. The monitored current is a sensitive indication of surface contamination and of compositional changes associated with the gas phase procedure. The technique is effectively utilized in fabricating devices such as semiconductor devices.