Design of a Dielectric Waveguide Switch in High-Resistivity Silicon for THz Applications

Abstract:
We present a concept for a dielectric waveguide switch at THz frequencies. The device is based on HR-Si and optimized for operation at 300 GHz. The switch is based on Y-shaped ridge segment, where the arms of the Y can be displaced via MEMS actuators. Simulations were performed utilizing the Beam Propagation Method (BPM), showing a transmission of 0.3 dB for the connected arm whereas a 11.8 dB crosstalk in the displaced arm is calculated for a 200 x 200 µm ridge geometry. The concept is designed with an almost-airclad effective-medium suspension that can be achieved via double sided DRIE on a silicon wafer. After manufacturing, the performance was measured in the WR-2.8 band. A 2D scan confirmed the concept, by showing a transmission of 6.8 dB showcasing a promising design for future MEMS integration on a THz platform.