Search for: All records

This paper demonstrates a novel approach to the design of D-band power dividers, capitalizing on the benefits of Substrate Integrated Waveguide (SIW) technology in 100-μm thick SiC substrate. By leveraging the unique characteristics of SIW and utilizing silicon carbide as the substrate material, an average insertion loss as low as 0.26 dB, and average return loss of up to 24 dB has been achieved in simulation in D-band. Although D-band dividers employing coplanar waveguides and microstrip lines have been reported, to the best of our acknowledge, this is the first work on D-band SIW power dividers. The SIW technology is compatible with GaN-on-SiC MMIC fabrication process flows, and provides a novel platform for the integration of low-loss millimeter-wave combiners with III-N based electronics. 

As 6G wireless communications push the operation frequency above 110 GHz, it is critical to have low-loss interconnects that can be accurately tested. To this end, D-band (110 GHz to 170 GHz) substrate-integrated waveguides (SIWs) are designed on a 100-μm-thick SiC substrate. The fabricated SIWs are probed on-wafer in a single sweep from 70 kHz to 220 GHz with their input/output transitioned to grounded coplanar waveguides (GCPWs). From CPW-probed scattering parameters, two-tier calibration is used to de-embed the SIW-GCPW transitions and to extract the intrinsic SIW characteristics. In general, the record low loss measured agrees with that obtained from finite-element full-wave electromagnetic simulation. For example, across the D band, the average insertion loss is approximately 0.2 dB/mm, which is several times better than that of coplanar or microstrip transmission lines fabricated on the same substrate. A 3-pole filter exhibits a 1-dB insertion loss at 135 GHz with 20-dB selectivity and 11% bandwidth, which is order-of-magnitude better than typical on-chip filters. These results underscore the potential of using SIWs to interconnect transistors, filters, antennas, and other circuit elements on the same monolithically integrated chip.