Less expensive high power plastic surface mount package

Abstract

A high power surface mount package including a thick bond line of solder interposed between the die and a heatsink, and between the die and a lead frame, wherein the lead frame has the same coefficient of thermal expansion as the heatsink. In one preferred embodiment, the heatsink and the lead frame are comprised of the same material. The package can be assembled using standard automated equipment, and does not require a weight or clip to force the parts close together, which force typically reduces the solder bond line thickness. Advantageously, the thermal stresses on each side of the die are effectively balanced, allowing for a large surface area die to be packaged with conventional and less expensive materials. One type of die that benefits from the present invention can include a transient voltage suppressor, but could include other dies generating a significant amount of heat, such as those in excess of 0.200 inches square.

Dependencies are inferred from the claim text.