Doping procedures for semiconductor devices
CA 2018976 C · Owner: Kuo, Jenn-Ming · Inventors: Luftman, Henry Steven; Kopf, Rose Fasano; Kuo, Jenn-Ming
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract, A process is described for making semiconductor devices with highly controlled doping profiles. The process involves minimizing or eliminating segregation effects caused by surface electric fields created by Fermi-level pinning. These electric fields act on dopant ions and cause migration from the original deposition site of the dopant ions. Dopant ions are effectively shielded from the surface electric fields by illumination of the growth surfaces and by backgrounddoping. Also certain crystallographic directions in certain semiconductors do not show Fermi-level pinning and lower growth temperatures retard or eliminate segregation effects. Devices are described which exhibit …
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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 June 14, 1990 and granted June 28, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 14, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 14, 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.