Integrated circuit stacking system and method

摘要

The present invention stacks packaged integrated circuits into modules that conserve PWB or other board surface area. The present invention can be used to advantage with packages of a variety of sizes and configurations ranging from larger packaged base elements having many dozens of contacts to smaller packages such as, for example, die-sized packages such as DSBGA. In a preferred embodiment devised in accordance with the present invention, a base element CSP integrated circuit and a support element CSP integrated circuit are aggregated through a flex circuit having at least two conductive layers that are patterned to selectively connect the two CSP elements. A portion of the flex circuit connected to the support element is folded over the base element to dispose the support element above the base element while reducing the overall footprint. The flex circuit provides a thermal and electrical connection path between the module and an application environment such as a printed wiring board (PWB).