Back to results
US 11,235,404 B2Granted
Personalized copper block for selective solder removal
AssigneeInternational Business Machines Corporation
InventorsCharles L. Arvin, Luca Del Carro, Thomas Brunschwiler, Thomas Weiss, Chris Muzzy
Life of this patent
Estimating the term…
Abstract
Disclosed are embodiments of forming porous copper on the end of a copper pillar. The embodiments may be used to remove solder from selected locations on a chip or laminate substrate.
Claims14
A method of forming a copper block for selective solder removal comprising the steps of:
- joining a copper pillar to a first substrate;
- creating a cavity in a second substrate;
- adding a predetermined quantity of copper-containing paste into the cavity;
- pressing an end of the copper pillar into the copper-containing paste in the cavity;
- and
- heating the copper pillar with the copper-containing paste in the cavity to a predetermined temperature to form a copper pillar having a predetermined volume of porous copper on the end of the copper pillar.
3 more elements
A method of selective solder removal comprising the steps of:
- joining a copper pillar to a first substrate;
- creating a cavity in a second substrate;
- adding a predetermined quantity of copper-containing paste into the cavity;
- pressing an end of the copper pillar into the copper-containing paste in the cavity;
- heating the copper pillar with the copper-containing paste in the cavity to a predetermined temperature to form a copper pillar having a predetermined volume of porous copper on the end of the copper pillar;
- applying the porous copper to a solder connection to be removed from a third substrate;
- and
- heating the porous copper and solder connection so as to cause melting of the solder connection and absorbing of the melted solder into the porous copper.
5 more elements
Dependencies are inferred from the claim text.