Vertical via-less transition in MCM technology for millimetre-wave applications

A vertical multilayer transition for millimetre-wave frequencies is introduced and implemented in IMEC multi-chip module (MCM) technology. Simulation and measurement results for a back-to-back CPW-to-microstrip transition prototype show excellent agreement. Moreover, the microstrip-to-microstrip vertical via-less transition, as the core idea that is introduced, demonstrates less than 0.7 dB of loss in the band from 57 to 66 GHz, which satisfies the European as well as US standard bandwidth for 60 GHz communications systems. The low insertion loss along with the straightforward design procedure makes the proposed vertical via-less transition a valuable candidate for 60 GHz communications systems.