Substrate-holding fixture of non-wettable material

摘要

A method for forming solder ball contacts on a Ball Grid Array (BGA) is described. The solder balls are formed by squeegeeing solder paste through apertures in a fixture into contact with pads on a substrate, and heating the fixture, paste and substrate to reflow the solder paste into solder balls that attach to the pads and are detached from the fixture. After cooling, the fixture is readily separated from the substrate while leaving the solder balls in positive (conductive) contact with contact pads on the substrate.