1x2 MEMS optical switch with sub 10 μs switching speed inside silicon gold coated planar hollow waveguides (PHW)

We present a new approach for guided-wave optical switches based on square silicon planar hollow waveguides (PHW). A 1times2 MEMS optical switch is manufactured by inserting into the hollow planar waveguide a micromechanical cantilever beam switch at the junction of Y waveguides. The small dimension of hollow planar waveguides (20 mum wide and 20 mum deep) and of the beam (2 mum wide and 250 mum long) allow very fast switching time below 10 mus. The fabrication steps to manufacture the switch need only two masks level. Gold coating enhances reflectivity inside hollow core. Planar hollow waveguides have another great advantage in the fact that optical function such as switching can be fabricated in the same process step than the hollow waveguide. This enables the fabrication of monolithic optical functions