A Low-Loss D-Band Chip-to-Waveguide Transition Using Unilateral Finline Structure

This paper presents a D-band interconnect realized using unilateral finline structure. The interconnect consists of a microstrip line implemented on a 75µm-thick SiC substrate. The line then couples to a unilateral finline taper that is mounted in the E-plane of a standard WR-6.5 D-band waveguide. The interconnect achieves low insertion loss and covers very wide frequency range. The measured minimum insertion loss is 0.67 dB and the maximum is 2 dB per transition across the entire D-band covering the frequency range 110–170 GHz. The transition does not require any galvanic contacts nor any special processing and can be implemented in any of the commercially available semiconductor technologies. This solution provides low-loss wideband packaging technique that enables millimeter-wave systems assembly using a high-performance simple approach.