Porous semiconductor material
CA 2178324 C · Owner: Qinetiq Limited · Inventors: Canham, Leigh Trevor
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Porous semiconductor material in the form of crystalline silicon (12) is produced with a porosity in exccess of 90 % and voids, crazing, and peeling of the material are substantially by scanning electron microscopy at a magnification of 7,000. The material (12) is prepared by anodization of a silicon wafer (10) to produce porous silicon followed by etching of the porous silicon to produce pore overlap defining silicon quantum wires. After etching the porous silicon is dried by supercritical drying. The resulting material has good properties together with good morphology and crystallinity.
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 November 17, 1994 and granted February 13, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 17, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 17, 2016.
- 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.