Experimental millimiter-wave 3D woodpile EBG waveguide manufactured by layer-by-layer dicing of silicon wafers

In this paper we report on the design, fabrication and measurement of a silicon woodpile waveguide operating in the millimeter-wave band. The 3D Electromagnetic Band Gap (EBG) woodpile has been created by precision dicing saws of silicon wafers. An appropriate air defect has been inserted at the structure central coordinates and optimized in size and shape in order to maximize the coupling between the TE 10 mode of the standard rectangular Input/Output metallic waveguides and the TE 10 - like mode of the EBG waveguide that propagates along the defect. The manufactured device, that includes custom metal-dielectric I/O transitions, exhibits an overall $\vert S_{11}\vert$ and $\vert S_{12}\vert$ scattering parameters of -32 dB and - 0.46 dB at the operating frequency of 96.6 GHz, which are in very good agreement with the simulated ones, obtained in Ansys HFSS.