Design and Fabrication of Reliable Power Efficient Bistable MEMS Switch Using Single Mask Process

Abstract

A bistable DC switch based on buckled beams and thermal actuation has been designed, fabricated and characterised. The buckled beams, which require very low actuation force and provide a sufficiently large contact force, are designed based on a parametric study. U-shaped thermal actuators are designed to provide the actuation force with minimum electrical power. The compact switch is fabricated using a simple single mask process on a SOI wafer. The average switching power is measured to be 60 mW, while the average switching delay is 350 μs. The power-delay product of about 20 μJ is the lowest reported so far for bistable MEMS switches based on thermal actuation. The switch retains functionality even after 5 million switching cycles.