BUMPED SUBSTRATE ASSEMBLY

摘要

A bumped substrate (800) assembly comprising an alumina substrate (802), a layer of copper (808) on the alumina substrate (802), and a heterogeneous junction band (806) between the alumina and the copper layer (808). Copper bumps (812, 814, 816, 818, 820, 822) integrally connected to the copper layer (808) extend therefrom, the copper in the copper layer (808) and the copper bumps (812, 814, 816, 818, 820, 822) is substantially identical. The heterogeneous junction band (806) has a copper-wetted surface area that is at least about twice the apparent surface area of the copper overlying the first junction band and consisting essentially of grains unitary with the copper layer (808) and being constituted by finger-like copper protuberances unitary with the copper layer (808) and occupying the space between the alumina grains.