WR-1.5 suspended silicon waveguide
A low-loss suspended silicon waveguide is presented, operating at the WR-1.5 frequency band (500–750GHz). A rectangular silicon strip is the main transmission channel. Two groups of silicon gratings are designed for holding up the rectangular silicon channel. The proposed waveguide is fabricated using the deep reactive ion etching (DRIE) micromachining technique due to its highly accurate dimensional control at THz frequency band. The silicon waveguide is bonded to a silicon substrate, whose part below the transmission channel has been etched for reducing the effect on the transmission loss of the waveguide. A transition between the suspended silicon waveguide to the standard metal waveguide is designed for connecting the measurement setup. The simulated loss of the suspended silicon waveguide is about 0.02dB/mm at 600GHz, which is better than the metal waveguide.