Monolithic on-wafer rectangular waveguide and its transition to CPW lines

In this paper, we are introducing the design and fabrication of a monolithic wafer-level micro-machined rectangular waveguide for millimeter-wave applications. The 3D fabrication process used in this study allows for fabrication of both dielectric-filled and air-filled monolithic on-wafer waveguides. To perform the measurement and provide integration option to other types of planar structures, a novel wafer-level CPW to waveguide transition is designed, fabricated and tested. This brings the opportunity of simultaneous wafer-level fabrication of the rectangular waveguide, CPW lines and the transition between these lines. To fabricate this structure, a combination of thin film and thick film process is used. The proposed structure brings the opportunity of fabricating the entire millimeter-wave waveguide systems on wafer-level. Besides, air-filled waveguide allows for further expansion of the topic and integrating the waveguides with MEMS actuators to produce monolithic waveguide MEMS switches.