An integrated circuit device incorporating a metallurgical bond to enhance
thermal conduction to a heat sink. In a semiconductor device, a surface
of an integrated circuit die is metallurgically bonded to a surface of a
heat sink. In an exemplary method of manufacturing the device, the upper
surface of a package substrate includes an inner region and a peripheral
region. The integrated circuit die is positioned over the substrate
surface and a first surface of the integrated circuit die is placed in
contact with the package substrate. A metallic layer is formed on a
second opposing surface of the integrated circuit die. A preform is
positioned on the metallic layer and a heat sink is positioned over the
preform. A joint layer is formed with the preform, metallurgically
bonding the heat sink to the second surface of the integrated circuit
die.