Lead-free tin-silver-copper alloy solder composition
CA 2475491 C · Owner: International Business Machines Corporation · Inventors: Choi, Won K.; Goldsmith, Charles C.; Puttlitz, Karl Sr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A solder composition and associated method of formation. The solder composition comprises a substantially lead-free alloy that includes tin (Sn) silver (Ag), and copper. The tin has a weight percent concentration in the alloy of at least about 90 %. The silver has a weight percent concentration X in the alloy. X is sufficiently small that formation of Ag3Sn plates (57 58) , is substantially suppressed when the alloy in a liquefied state is being solidified by being cooled to a lower temperature at which the solid Sn phase is nucleated. This lower temperature corresponds to an undercooling .delta.T relative to the eutectic melting temperature of the alloy. Alternatively X , may be …
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 11, 2003 and granted March 27, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 11, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 11, 2025.
- 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.