Patent ID: 8269340

Claim:
A microelectronic package comprising: a substrate; a circuit chip mounted on the substrate; a heat spreader/lid on the circuit chip, wherein the heat spreader has an underside surface comprising at least one curvilinear contour; and a thermal interface material (TIM) applied between the circuit chip and the heat spreader/lid, wherein the curvilinear contour comprises one positive or protruding curvilinear feature, and one negative or recessed curvilinear feature, wherein the positive or protruding curvilinear feature aligns with low stress regions in the TIM between the heat spreader/lid and circuit chip, and results in an increase in heat dissipation, wherein the negative or recessed curvilinear feature aligns with a high stress region in the TIM between the heat spreader/lid and circuit chip, and results in a reduction in mechanical stress.