Electronic package with thermally conductive standoff

A method of attaching an electronic module to a substrate therefor, comprising:

• positioning a thermally conductive and resilient standoff layer onto a substrate hosting a peripheral array of solder balls on contact pads such that said thermally conductive standoff layer is located central to said peripheral array of solder balls, said thermally conductive standoff layer having a relaxed height greater than the height of said solder balls;
• positioning an electronic module on said thermally conductive standoff layer with said electronic module having a peripheral array of contact pads around a central cavity having a semiconductor device bonded therein, said electronic module being positioned so that said peripheral array of contact pads align with said peripheral array of solder balls;
• applying a temporary force to said electronic module to cause said peripheral array of contact pads on said electronic module to come into contact with said peripheral array of solder balls;
• heating said solder balls to a temperature sufficient to cause reflow and make electrical connections between said peripheral array of solder balls and said peripheral array of contact pads;
• removing said temporary force from said electronic module so as to put said electrical connections under tension;
• positioning a heat sink on said electronic module on the side of said module opposite to the side of said thermally conductive standoff layer;
• and
• applying a compression force to said heat sink to clamp said electronic module and said thermally conductive standoff layer to said substrate to relieve said tension.

An electronic module and substrate assembly, comprising:

• an electronic module having an array of peripheral contact pads on one surface around a central portion encapsulating a semiconductor device with bonding material;
• a substrate for said electronic module, said substrate having an array of contact pads formed in a pattern that matches the location of said peripheral contact pads on said electronic module and are electrically connected thereto;
• a thermally conductive and resilient standoff positioned between and unbonded to said electronic module and said substrate, said thermally conductive standoff having openings therethrough so as to provide air pathways that permit thermal dissipation by both convection and thermal conduction;
• and
• mechanical compression apparatus for applying a compression force to said electronic module and said substrate to mechanically clamp said thermally conductive standoff therebetween with said thermally conductive and resilient standoff providing sufficient resilient force so as to offset said compression force to the connections between said electronic module and substrate.