Patent ID: 6127204
Filing Date: 2000-10-03
Classification: H05K,Y02P

Abstract:
A method of mounting an electronics module on a planar card, comprising:a) providing an electronics module having an array of solder protrusions from one surface thereof for forming electrical connections;b) providing a planar card having vias and a wiring pattern, said planar card further having an array of shallow recessed areas for placement of said electronics module, wherein said shallow recessed areas each have a depth between 0 and 0.2 millimeters;c) screening a solder paste onto the planar card, each of the recessed areas facilitating a high solder volume to accommodate the solder paste in the recessed areas as well as the solder paste that may flow into each of the vias;d) holding the array of solder protrusions in contact with a corresponding array of shallow recessed areas formed in the card and electrically connected to the wiring pattern;e) reflowing the solder paste to form an array of solder joints between the solder protrusions and the wiring pattern at the recessed areas, the solder joints being held in place by surface tension between the solder protrusions and the shallow recessed areas; andf) cooling the planar card to solidify the solder joints in place at the recessed areas with the module spaced above the planar card for movement in a direction parallel to the planar card during thermal cycling of the module.