Hybrid core substrate architecture for high speed signaling and fli/sli reliability and its making

Abstract

Embodiments include a package substrate, a semiconductor package, and a method of forming the package substrate. A package substrate includes a core substrate between a first alternate core substrate and a second alternate core substrate. The first alternate core substrate includes conductive layers and vias. The package substrate includes a dielectric layer surrounding the core and first and second alternate substrates, a first conductive layer on a top surface of the dielectric layer, and a second conductive layer on top surfaces of the core and first and second alternate substrates, where the dielectric layer is over/under the core and first and second alternate substrates. The package substrate includes a third conductive layer on bottom surfaces of the core and first and second alternate substrates. The conductive layers are coupled to the vias within the first alternate core substrate, where the conductive layers and vias couple the second and third layers.