Semiconductor device and method of forming fine pitch conductive posts with graphene-coated cores

A semiconductor device has a substrate and an electrical component disposed over a first surface of the substrate. A first encapsulant is deposited over the first surface of the substrate. A second encapsulant is deposited over a second surface of the substrate with a via formed in the second encapsulant. A conductive material containing a graphene core shell is deposited in the via in the second encapsulant to form a conductive post. The graphene core shell can have a copper core with a graphene coating formed over the copper core. The conductive material has a matrix to embed the graphene core shell. The conductive material can have a plurality of cores covered by graphene and the graphene is interconnected within the conductive material to form an electrical path. The conductive material can have thermoset material or polymer or composite epoxy type matrix to embed the graphene core shell.