Patent ID: 9698072
Date: 2017-07-04
CPC Classifications: H01L

Claim:
1. A flip-chip structure comprising: a substrate; an interposer disposed above the substrate; a first die disposed above the interposer; a second die disposed above the first die; and a third die disposed above the second die; wherein a first interface is formed between the substrate and the interposer, a second interface is formed between the interposer and the first die, and a third interface is formed between the second die and the third die; wherein the first interface comprises an interior region and a periphery region, the periphery region extending from a perimeter of the interposer to an outermost solder connection between the substrate and the interposer; a plurality of solder connections in the first interface; a plurality of gaps between the plurality of solder connections; a first underfill material occupying the plurality of gaps located in the interior region of the first interface, the first underfill material in direct contact with the substrate, and the interposer, and at least one of the plurality of solder connections; and a second underfill material occupying the periphery region of the first interface, the second underfill material in direct contact with the first underfill, the substrate, the interposer, and wherein the second underfill material terminates at the outermost solder connection.