Thin multi-chip flex module
A multichip module comprises a flexible circuit having conductive patterns on its surface(s) to which microelectronic device(s) are attached. The flexible circuit is enclosed and supported by two rigid frames, which may further be provided with protective heat spreading covers. Contact pads on the rigid frame(s) may be configured to engage a mating socket or they may be solderable to a printed circuit board.
1 . A method for making a multichip module comprising the steps of:
forming a flexible dielectric substrate having a conductive pattern on at least one surface thereof, said conductive pattern including a plurality of contacts adjacent to one edge of said substrate;
attaching a plurality of microelectronic devices to said substrate so that said microelectronic devices are operably coupled to said conductive pattern;
attaching two substantially rigid frames to said flexible dielectric substrate, said frames extending around the periphery of said substrate, one on each surface thereof, at least one of said frames having external contact pads; and,
forming electrical connections between said contact pads and respective contacts on said conductive pattern on said substrate.
2 . The method of claim 1 wherein said substrate has a conductive pattern on both surfaces thereof, said microelectronic devices are mounted on both of said surfaces, and each of said two frames has external contact pads.
3 . The method of claim 2 wherein said dielectric substrate further contains vias connecting at least a portion of said conductive patterns on said first and second surfaces.
4 . The method of claim 1 wherein said microelectronic devices are selected from the group consisting of: memory circuits, logic circuits, buffer devices, interface devices, optoelectronic devices, and microprocessors.
5 . The method of claim 1 wherein said frames further include heat spreading covers.
6 . The method of claim 1 wherein said external contact pads are configured to engage a mating socket.
7 . The method of claim 1 wherein said external contact pads are configured to be solderable to a printed circuit board.
8 . The method of claim 1 wherein said frames are attached to said substrate by a substantially continuous layer of adhesive along their perimeters.
9 . The method of claim 1 wherein said frames are held together by engaging a mechanical fastener.