Present and future directions for multichip module technologies

Multichip modules (MCM's) have been actively developed in recent years. They are expected to provide high-performance systems by packing bare chips at a high density. In particular, a thin-film interconnect substrate that can accommodate higher wiring capacity in a few layers is a new option for coping with high pin count and fine pad pitch VLSI's. MCM's require various kinds of technologies including the fabrication processes of interconnect substrates, chip connection methods, electrical design, thermal management, known good die (KGD), and so on. The state of the art of MCM technologies is reviewed and future directions are discussed.