Sub-micron device fabrication
CA 2061624 C · Owner: American Telephone And Telegraph Company · Inventors: White, Donald Lawrence
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Fabrication of integrated circuits - electronic photonic or, hybrid - permits attainment of higher device density. Pattern delineation with smaller design rules than previously associated with delineating radiation of given wavelength is the consequence of use of phase masks. Compared with earlier used binary valued, phase masks, the multiple values of those on which this fabrication depends permits improved effectiveness in lessening of edge-smearing radiation of consequence (of diffraction-scattered delineating radiation at feature edges). Phase masking mayprovide as well, for feature generation by interference and for reduced intensity of, unwanted image hot spots by diffraction.
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 February 21, 1992 and granted February 2, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 21, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 21, 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.