Development of a plastic encapsulated multichip technology for high volume, low cost commercial electronics

Non-military/noncomputer electronics industry segments such as PC´s, workstations, portable electronics, the automotive and medical industries, automated test equipment, and high-end consumer goods, are evolving rapidly. They demand higher complexity and higher performance circuits and components. At the same time, many of these industry segments are being driven to shrink size, weight, and power dissipation. Standard low cost packaging approaches such as thru-hole PCB and chip and wire hybrids, can no longer efficiently interconnect these more complex circuits. These industry segments are being forced to turn to new higher performance packaging approaches such as SMT, MCM, and COB. This paper describes an innovative embedded chip MCM technology that eliminates high cost structures, as well as materials and processes in current thin film MCM technologies. A plastic encapsulated multichip technology has been developed in which an epoxy encapsulant is molded around bare die to form the MCM substrate. This new MCM process readily scales-up to high volume production and is inherently high yielding, while maintaining all of the performance advantages of the GE developed overlay HDI process. This paper describes the thermal, mechanical, and chemical stability issues that drove this development, the process used to fabricate the modules, and the cost and yield advantages associated with this structure