Solder ball connections and assembly process
CA 2134019 C · Owner: Corbin, John S. Jr. · Inventors: Caulfield, Thomas; Corbin, John S. Jr.; Banks, Donald Ray
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
High melting temperature Pb/Sn 95/5 solder balls ale connected to copper pads on the bottom of a ceramic chip carrier substrate by low melting temperature eutectic Pb/Sn solder. The connection is made by quick reflow to prevent dissolving Pb into the eutectic solder and raising its melting temperature. Then the module is placed on a fiberglass-epoxy circuit board with the solder balls on eutectic Pb/Sn solder bumps on copper pads of the board. The structure is reflowed to simultaneously melt the solder on both sides of the halls to allow each ball to center between the carrier pad and circuit board pad to form a more symmetric joint. This process results in structure that are more reliable …
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 October 21, 1994 and granted March 30, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 21, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 21, 2016.
- 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.