Lapping and polishing method and apparatus for planarizing photoresist and metal microstructure layers
CA 2245498 C · Owner: Wisconsin Alumni Research Foundation · Inventors: Guckel, Henry; Mangat, Pawitterjit S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for planarizing photoresist and/or metal microstructure layers is provided. Planarization is achieved by removing material from a workpiece (64) by lapping using a diamond containing lapping slurry (58). A lapping machine is furnished with a lapping plate (50) made of a soft metal material. The lapping plate (50) is furnished with ridges of controlled height using a diamond conditioning ring (62) with a specified grit size. Free diamonds in a liquid slurry (58) are then sprayed onto the plate (50) and embedded therein by a second conditioning ring. After the lapping plate (50) is conditioned, the piece to be lapped (64) is mounted on the lapping plate (50). A …
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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 January 28, 1997 and granted March 19, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 28, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 28, 2019.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.