A micromachined WR-3 waveguide with embedded bends for direct flange connections

A novel micromachined waveguide bend operating in the frequency range 220-325 GHz is presented. It provides for a direct and accurate connection with standard waveguide flanges. A structure of two back-to-back right angle bends and a straight 16mm long WR-3 rectangular waveguide has been fabricated and tested using a UG-387 flange. The structure is made of four layers of metallised SU-8 pieces using a micromachining technique. The measurements show a return loss of -20dB and a normalized insertion loss of 0.134 dB/mm at 300 GHz.