Multi-layer thin-film substrates for multi-chip packaging

It is commonly recognized that multiple chip module (MCM) packaging offers great advantages in system performance by virtue of the elimination of an entire level of interconnection. Multilayer thin-film module technologies for high-performance multiple chip packaging were developed and integrated. The technologies, which feature four copper layers, polyimide dielectric, controlled-impedance transmission lines, and solder bump assembly, were demonstrated on a variety of vehicles including, recently, a 4-kbyte RAM module operating at above 100-MHz clock frequency. The generic MCM substrate technology is described. The process can be designed to be compatible with a number of substrate materials as required for specific applications.>