Design and Fabrication of Suspended Indium Phosphide Waveguides for MEMS-Actuated Optical Buffering

We present the design and fabrication of suspended optical waveguides on indium phosphide platform for use in an optical buffer device with MEMS actuation, in which the optical delay can be achieved by changing the spacing of the waveguides by electrostatic actuation. The optical and mechanical properties of the waveguides and pillar supports are modeled, and different MEMS actuation schemes are simulated. We also present fabrication and characterization results of the epitaxially grown sample structure and of the suspended waveguide device, exhibiting two parallel waveguides with submicron dimensions separated by a 400-nm air gap, and suspended at 40-μm intervals by S-shaped supports.