Signal propagation in high-speed MCM circuits

This paper describes the analysis of the propagation of digital signal on a thin-film multichip module (MCM) substrate populated with CMOS integrated circuits. Timing analyses and circuit simulations were performed during the design of an MCM consisting of 4 bare 0.7-μm CMOS ASIC´s (100 pins, 64 mm², standard cell technology) transmitting signals at 200 Mbit/s on a 5-layer thin-film substrate (1-by-1 inch, 2 interconnection layers). This paper addresses mainly two problems related to the design of microsystems where trade-offs must be found between high frequency and high density requirements: 1) an accurate description of the chip-to-chip, propagation of the signals, including the combined influence of active devices (drivers and receivers) and coupled, lossy interconnection lines: 2) an accurate overview of the way parameters from different domains (geometrical, electrical and technological) interact with each other and affect together the signal propagation. It is shown how the results of such analyses can help solving trade-offs between different requirements and taking decisions during the system design phase