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:
Apr. 10, 2001
Filed:
Nov. 01, 1999
Chemical mechanical polishing endpoint detection by monitoring component activity in effluent slurry
William Graham Easter, Orlando, FL (US);
Sudhanshu Misra, Orlando, FL (US);
Pradip Kumar Roy, Orlando, FL (US);
Susan Clay Vitkavage, Orlando, FL (US);
Lucent Technologies, Inc., Murray Hill, NY (US);
Abstract
A method for determining the endpoint in a chemical mechanical polishing operation used for polishing a metal-containing material. An acidic polishing slurry is used to oxidize the metal and the oxidized metal is included in an effluent slurry stream. The effluent slurry stream is directed into a vessel which forms an electrochemical cell. The component activity of the effluent slurry stream is monitored within the electrochemical cell by measuring the electric potential across the electrodes of the electrochemical cell. When the measured electric potential changes, indicating a change in the composition of the effluent slurry, endpoint is indicated.