Solder process and solder alloy therefor

A soldering process comprising the steps of:

• depositing on an interconnect pad of an integrated circuit device a solder alloy consisting essentially of, by weight, 50% to 65% indium, 0.5% to 3.0% silver, 0.0% to 3.0% copper, the balance lead and incidental impurities, the solder alloy having a solidus temperature in a range of about 173° C. to about 178° C. and a liquidus temperature in a range of about 187° C. to about 196° C.;
• reflowing the solder alloy to form a solder bump on the interconnect pad, the solder bump comprising a layer of silver-indium and/or copper-indium intermetallic compound contacting the interconnect pad as a result of the reflowing step;
• registering the solder bump with a metal trace on a laminate substrate;
• and then
• reflowing the solder bump to form a solder joint that metallurgically joins the interconnect pad to the metal trace so as to attach the integrated circuit device to the laminate substrate, the layer of silver-indium and/or copper-indium intermetallic compound contacting the interconnect pad.