One step capillary underfill integration for semiconductor packages

A method of applying underfill material comprising:

• attaching a semiconductor die to an integrated heat spreader and a substrate to form a semiconductor package;
• dispensing an underfill material at the perimeter of two adjacent sides of an integrated heat spreader, wherein said underfill material flows between said integrated heat spreader and said substrate and flows between said integrated heat spreader and said semiconductor die to fill said integrated heat spreader area through capillary action;
• and
• providing mechanical stability to said semiconductor package by directly contacting said underfill material to said substrate, said integrated heat spreader, and
• said semiconductor die.

A method of forming a semiconductor package comprising:

• thinning a semiconductor wafer to form a thinned semiconductor wafer;
• depositing metal on backside of said thinned semiconductor wafer;
• partitioning semiconductor wafer into a plurality of die;
• soldering one of said plurality die to an integrated heat spreader to form a composite;
• dispensing a flux material to a substrate;
• aligning said die and said integrated heat spreader composite on said substrate;
• soldering said composite to said substrate to form solder joints;
• wherein said soldering forms a semiconductor package comprising said die, said integrated heat spreader, and said substrate;
• pre-heating said semiconductor package;
• dispensing an underfill material at the perimeter of two adjacent sides of an integrated heat spreader and perpendicular to the substrate, wherein said underfill material flows between said integrated heat spreader and substrate and flows between said integrated heat spreader and semiconductor die to fill said integrated heat spreader area through capillary action and
• providing mechanical stability to said semiconductor package by directly contacting said underfill material to said substrate, said integrated heat spreader, and said semiconductor die.