Capacitively coupled radiofrequency plasma source
CA 2049876 C · Owner: Robinson, Raymond S. · Inventors: Kaufman, Harold R.; Robinson, Raymond S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A plasma source is disclosed in which a pair of dissimilarly-sized electrodes are driven by a radiofrequency source to create a plasma. A magnetic field is oriented to be parallel to a surface area on the smaller electrode. The field strength increases to either side of that smaller electrode. As shown, ions are electrostatically accelerated out of the plasma but they, instead may be accelerated magnetically electrons may in, the alternative be extracted or there may be no accelerating mechanism.
Read the whole patent
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 August 26, 1991 and granted February 10, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 26, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 26, 2013.
- 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.