Method of preparing semiconductor wafer with good intrinsic gettering
CA 2064486 C · Owner: Comeau, Alain · Inventors: Comeau, Alain
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of preparing semiconductor wafers with intrinsic gettering capability, comprises the steps of: carrying out a high temperature oxidation in the on a doped semiconductor wafer for between about 20 to 60 minutes to form an initial oxidation layer; heating said wafer at a moderate temperature in an inert atmosphere for about 1 to 4 hours to initiate formation of crystal nuclei; ramping up the temperature in said inert atmosphere to a temperature of at least about 850°C at a rata of about 1 - 10°C/min.; and subsequently carrying out well diffusion on the wafer at a temperature of at least about 1000°C.
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 March 31, 1992 and granted August 21, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 31, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 31, 2014.
- 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.