The Microfabrication of Monolithic Miniaturized Ridged Half-Mode Waveguides for 5G Millimeter-Wave Communication Systems

Within this work, a novel millimeter-wave design platform is introduced, utilizing conventional microfabrication techniques to produce fully monolithic miniaturized 3D ridged half-mode waveguides. These structures offer substantial die real estate reduction compared to previously reported wafer-level waveguides, while also offering the opportunity for improvements in integration and fabrication yield. The microfabrication process flow is outlined, and a fabricated prototype is measured. A ridged half-mode waveguide is designed and fabricated with cutoff frequency of 58 GHz, for operation within E-band. The measured results show attenuation loss as low as 0.3 dB/mm, while achieving 63% miniaturization over standard rectangular monolithic 3D waveguide previously reported. Independent from the carrier substrate performance, the proposed air-filled monolithic ridged half-mode waveguide demonstrates potential to provide enhanced integration technology suitable for millimeter-wave communication.