Multichip Modules—The Hybrid for Wafer‐scale Integration

Existing IC packaging and interconnection is creating a barrier for advances taking place in IC technology. Wafer scale integration (WSI) is being proposed as the next major step in electronics, bringing with it the removal of a large number of these barriers. However, there are still major problems with WSI technology that are unlikely to be solved before the late nineties. In the meantime a new packaging and interconnection technology will be introduced—the multichip module (MCM), which will act as a hybrid for WSI. The MCM will not make the PCB obsolete, though it will pose threats and opportunities to important parts of the thick film hybrid industry. The MCM, for the purposes of this paper, is defined as a thin film multilayer interconnect structure utilising IC manufacturing type processes. MCM technology is not confined to high performance systems; it will be used across the whole of the electronics industry including the consumer sector, with a circuitised substrate world market of nearly $7 bn by 1997.