Flexible advanced packaging

A new era of electronic packaging is upon us. Some ten years ago we were wire bonding discrete transistors to substrates to form what was termed hybrid circuits. As the technology advanced, integrated circuits became the watchword and have taken a commanding position in the digital, memory and linear marketplaces. Packaging of these integrated circuits has virtually all related to aluminum or gold wire bonding to either metal headers, flatpacks, ceramic DIPs or plastic DIPs. In turn, these packages for the most part have been connected to substrates by such techniques as wave soldering or wire wrapping. Selected companies are involved in handling integrated circuit die at the hybrid substrate level, but they either represent large, captive companies with their own flip chip process and a huge capital investment or small hybrid houses that are wire bonding small quantity orders. It would appear that the state of the art of integrated circuits has surpassed that of packaging. But today a new technique of bonding, that eliminates wires or flying leads, and is more than cost competitive, is becoming available. This new bonding technique is one that allows an integrated circuit die to have all of its leads simultaneously bonded to inner lead conductors on a continuous, flexible substrate. The die is then encapsulated and the outer lead bonds of the substrate are attached to the outside word after testing of the individual substrate frame. Not only has wire bonding been eliminated, but we now have a low cost packaging technique that lends itself to all levels of integration including semiconductor, components, sub-systems and systems houses. At present this technique, as described, is being used in the new Polaroid SX-70 camera.