Patent attributes
A chip-on-wafer-on-substrate (CoWoS) semiconductor assembly is formed which includes a chip-on-wafer (CoW) sub-assembly of integrated circuit (IC) dies mounted on an interposer, which is in turn mounted on a package substrate with a top metallization stack and a bottom metallization stack using bonding bumps connecting the backside of the interposer and the front side of the package substrate. The bonding bumps provide electrical connections between the ends of through-vias exposed at the backside of the interposer and the top metallization stack of the package substrate. The likelihood of certain failure mechanisms that can adversely affect CoWoS yield are reduced or eliminated by ensuring a total metal thickness of the top metallization stack is greater than a total metal thickness of the bottom metallization stack, but not so much greater as to induce cracking of the underfill material during curing thereof.
