Freestanding, micromachined, multimode silicon optical waveguides at λ = 1.3 μm for microelectromechanical systems technology

Freestanding, multimode optical channel waveguides formed by micromachining silicon are demonstrated. Fabrication utilizes standard microelectromechanical systems (MEMS) technology. Losses in the 0.57–0.80-dB/cm range are measured for channel waveguides with an air–silicon–air structure, whereas losses in the 1.12–1.52-dB/cm range are measured for channel waveguides with a SiO2–silicon–SiO2 structure. Freestanding channel waveguides, along with optical fibers and other MEMS structures, can readily be mounted on a silicon MEMS platform to provide optimal alignment for maximizing optical coupling, and they are thus expected to be useful in devices that involve light and MEMS structures.