Patent ID: 7147735

Claim:
A method comprising: providing a die having a first side with a plurality of die bumps and a substrate having a second side with a plurality of substrate bumps, with a selected one of the plurality of die bumps and the plurality of substrate bumps being a plurality of solder bumps and the non-selected one of the plurality of die bumps and the plurality of substrate bumps being a plurality of metal bumps; forming a layer of underfill material on a surface having the plurality of solder bumps; moving at least a selected one of the die and the substrate to bring the plurality of die bumps into contact with the plurality of substrate bumps after forming the layer of underfill material; vibrating at least a selected one of the die and the substrate while the die bumps and the substrate bumps are in contact to impart a substantially lateral oscillating motion to reduce entrapment of the underfill material between the die bumps and the substrate bumps; and reflowing the plurality of solder bumps to join the plurality of solder bumps to the plurality of metal bumps by heating the plurality of solder bumps with a heater to a given temperature, with the given temperature being equal to or greater than a melting point temperature of the solder bumps and less than a melting point temperature of the metal bumps.