SU-8 micromachining of millimeter and submillimeter waveguide circuits

Micromachined WR 3.4 waveguide circuits are fabricated using a SU-8 micromachining process. In order to demonstrate the viability and repeatability of this process both straight waveguide sections and cylindrical cavity resonators are fabricated and measured. The SU-8 waveguide compares reasonably well to a standard WR 3.4 waveguide section. The measured cavity resonators demonstrate quality factors of 1900 and 2200 at a resonant frequency of 308 GHz.