Full-Band Silicon-Micromachined E-Plane Waveguide Bend for Flange-to-Chip Connection

This article presents a novel design of a full-band
E
-plane waveguide bend for direct flange-to-chip connection. The proposed
E
-plane bend concept is validated with a reduced-height bend prototype designed for standard WR-3.4 waveguide flange-to-chip connection, fabricated by silicon micromachining, and characterized by de-embedding the
S
-parameters with a custom-made offset-short calibration kit. The measured insertion and return losses are 0.08–0.3 dB and better than 14.7 dB, respectively, for the whole waveguide band of 220–320 GHz, and better than 0.15 and 20 dB, respectively, for more than 80% of the waveguide band. The measured results are in excellent agreement with the simulation data. Besides, a two-port waveguide structure with WR-3.4 interfaces is fabricated and measured to confirm the functionality of the designed
E
-plane bend. Furthermore, sensitivity analysis shows the robustness of the proposed geometry against fabrication tolerances.