Ultra low loss millimeter wave multichip module interconnects

We present the design and electrical characterization of a multilayer organic based multichip module (MCM) for use at W-band (75-110 GHz). The ultra-low loss microstrip transmission line on Kapton E(R) (a trademark of DuPont) thin films and benzocyclobutene (BCB) adhesives is reported at W-band. An electrical model for a vertically stacked via interconnect to an integrated circuit (IC) is experimentally developed. This interconnect exhibits very low parasitics and preserves excellent matched conditions for devices and circuits in a module. The electrical performance of the vertically stacked via offers superior performance relative to ribbon and wire bond results reported in the literature at millimeter wave frequencies. We conclude that this technology is capable of realizing compact modules at millimeter wave frequencies.