Abstract: An improved multichip semiconductor module compatible with existing SIMM memory sockets comprising a molded module frame and a composite semiconductor substrate subassembly received in a cavity in said frame. The composite semiconductor substrate subassembly or subassembly(s) comprises a plurality of semiconductor devices which are connected to electrical contacts on an edge of the molded frame by a variety of configurations described herein. In one embodiment of the invention, the subassembly(s) includes a composite substrate which comprises a thin metal cover plate and thin laminate circuit which is bonded to the metal cover plate by a film adhesive. The composite substrate provides a mounting surface for the placement of semiconductor devices and their associated passive components.