Submicron silicon waveguide optical switch driven by microelectromechanical actuator

A submicron silicon waveguide optical switch driven by a microelectromechanical actuator is fabricated. The switch is composed of single-mode silicon input and output waveguides and a movable waveguide suspended by silicon springs. Switching occurs when the air gap between input and output waveguides is closed by displacing the movable waveguide 540±20 nm by an electrostatic comb actuator. The switch, fabricated on a silicon-on-insulator wafer, is monolithic, and active switching region is as small as about 40×60 μ m2. An extinction ratio of 15±2 dB is experimentally obtained between switch off and on states at 1.55 μm wavelength.