In an integrated circuit packaging structure, such as in a SCM, DCM, or MCM, a method and apparatus for increasing heat spreader size and thus thermal performance is disclosed. The packaging structure includes a first substrate; an electronic device operably coupled to a top surface defining the first substrate; a heat spreader having a first surface operably coupled to a top surface defining the electronic device and an opposite second surface in thermal communication with a second substrate; and a frame defining an opening therethrough. The frame is further defined by an inwardly extending ledge configured to allow the heat spreader to extend at least to a peripheral edge defining a perimeter of the first substrate. In an exemplary embodiment, the second substrate includes one of a heat sink, cooling plate, thermal spreader, heat pipe, thermal hat, package lid, or other cooling member.