Development of 1 × 4 MEMS-based optical switch

Abstract

In this paper, a novel 1×4 optical switch has been developed based on the DRIE vertical mirror technology. Three microactuated vertical silicon mirrors and five tapered/lensed fibers were employed to perform the 1×4 switch function. The comb actuators drive the mirrors linearly into the optical path due to the electrostatic force. The tilted mirror with an angle of 22.5° made the layout of the mirrors and optic fibers more compact. Finite element method (FEM) modeling on the linear comb actuator was implemented to verify the design. Deep reactive ion etching (DRIE) process was employed to fabricate the mirrors, combs and U-grooves on a SOI wafer. A satisfactory yield (up to 70%) was achieved during the microfabrication due to the compactness of the single photomask process. The prototype of the optical switch was packaged and systematically characterized in terms of bonding properties, optical performance including insertion loss, return loss, cross talk, and switch time. The design and microfabrication has been demonstrated to be successful. The packaging technique can be utilized in the similar category of optical MEMS devices. The optical performance of our switch exhibits the great promise in the application of optical networks.