Method of chemical-mechanical polishing an electronic component substrate and polishing slurry therefor
CA 2011709 C · Owner: Guthrie, William L. · Inventors: Rodbell, Kenneth P.; Guthrie, William L.; Patrick, William J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a method of chem-mech polishing an electronic component substrate. The method includes the following steps; obtaining a substrate having at least two features thereon or therein which have a different etch rate with respect to a particular etchant; and contacting the substrate with a polishing pad while contacting the substrate with a slurry containing the etchant wherein the slurry includes abrasive particles, a transition metal chelated salt and a solvent for the salt. The chem-mech polishing causes the at least two features to be substantially coplanar. Also disclosed is the chem-mech polishing slurry.
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed March 7, 1990 and granted December 21, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 7, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 7, 2012.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.