A D-Band Rectangular Waveguide-to-Coplanar Waveguide Transition Using Wire Bonding Probe

This paper presents a rectangular waveguide-to-coplanar waveguide (CPW) transition at D-band (110-170 GHz) using wire bonding probe. A conventional CPW is designed and fabricated based on both quartz and glass substrates for estimating the losses at D-band and testing the fabrication processes. Two transition prototypes at D-band using E-plane probe and wire bonding probe are designed, fabricated, and measured in a back-to-back configuration. The system packaging approaches and scattering parameters of the transition prototypes are compared. For both on-chip and carrier substrate approaches, chips can be tested individually before packaged into a system and extra connections are not required. The fabricated rectangular waveguide-to-CPW transition at D-band using wire bonding probe in a back-to-back configuration exhibits a bandwidth of 56.3 GHz ranging from 110 to 166.3 GHz in which the return loss is better than 10 dB with an associated insertion loss of 2 dB. Compared with the fabricated rectangular waveguide-to-CPW transition using E-plane probe, an equivalent bandwidth is achieved at D-band while the system packaging approaches are more versatile and compact for the proposed transition using wire bonding probe.