Microelectronic assembly with stiffening member

Abstract

A flip chip-ball grid array package and a stiffening ring having first and second faces, and grooves formed in at least a one of the first and second faces of the stiffening ring. Providing grooves in at least one of the faces of the stiffening ring imparts of degree of flexibility to the stiffening ring to overcome and accommodate stresses induced in the manufacturing process associated with adhesive curing, solder reflow, chip underfilling and cavity filling, and differences in the coefficient of thermal expansion of the various materials used to construct the assembly. Furthermore, forming grooves in at least one of the faces of the stiffening ring provides increased surface area and therefore improves the heat transfer property of the stiffening ring. At the same time, the stiffening ring provides a sufficient degree of rigidity to the first substrate and to the microelectronic assembly in general to facilitate handling of the microelectronic assembly without damaging the chip or its solder connections.

Dependencies are inferred from the claim text.