Generic design rules for high-speed MCM's

An advanced software package has boon developed that allows for the detailed electrical simulation of MCM's. The performance of some MCM architectures has been investigated, with emphasis given on the dependence of crosstalk and line charac teristic impedance on specific interconnecting geometries and dielectric constant values. The topologies simulated may be classified in three categories : (a) simple multilayer matallizations, (b) active conducting path layers separated by ground planes and (c) interconnection lines separated by ground wires. Comparison of simulation results showed that the third topology is superior as far an crosstalk, signal losses and line characteristic impedance are concerned; a dramatic reduction of cronstalk (-35 Db) follows the reduction of the distance between conductors and ground wires below 8 /spl mu/m, independently of the values of the dielectric constants of the insulating layers and may be further reduced down to -55 Db, if the output impedance of the inactive line is around 50 Ohms. Furthermore, the adoption of the third topology also decreases the interconnection line characteristic impedance by about 25% to 40% for various conductor widths.