Electron-detector diode biassing scheme for improved writing by an electron beam lithography machine
CA 2022251 C · Owner: Etec Systems, Inc. · Inventors: Devore, William Jay
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a biassing scheme for a beam position location apparatus (50) which comprises electron detector diodes (52) in an electron beam lithography machine (10) such that the detector diodes (52) deposit fewer secondary electrons (62) on a substrate (16) being processed by the electron beam (22) and thus reduce or eliminate any charge buildup on said substrate which deflect the electron beam (22) causing pattern distortion.
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 July 30, 1990 and granted July 7, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 30, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 30, 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.