A method of fabricating microelectronic dice by providing or forming a
first encapsulated die assembly and a second encapsulated die assembly.
Each of the encapsulated die assemblies includes at least one
microelectronic die disposed in a packaging material. Each of the
encapsulated die assemblies has an active surface and a back surface. The
encapsulated die assemblies are attached together in a back
surface-to-back surface arrangement. Build-up layers are then formed on
the active surfaces of the first and second encapsulated assemblies,
preferably, simultaneously. Thereafter, the microelectronic dice are
singulated, if required, and the microelectronic dice of the first
encapsulated die assembly are separated from the microelectronic dice of
the second encapsulated die assembly.