Silicon Micromachined Components at Terahertz Frequencies for Astrophysics and Planetary Applications

At the Jet Propulsion Laboratory (JPL) we are using deep reactive ion etching (DRIE) based silicon micromachining to develop the critical waveguide components at submillimeter wavelengths that will lead to highly integrated multi-pixel spectrometers, imagers, and radars. The advantage of DRIE over wet anisotropic etching is that DRIE exhibits little crystal plane dependence and therefore reduces geometric restrictions. As a result, DRIE enables fabrication of trenches that are independent of crystal planes, thus making it possible to develop micromachined waveguides with vertical sidewall profiles. In this paper we describe the design and fabrication of silicon micromachined critical waveguide components operating in the range 325-500 GHz frequency band for astrophysics and planetary applications from space. We also address the challenges of testing these devices when interfaced with metal waveguide test fixtures.