Influence of cold arm thickness on mechanical property of U-shaped polycrystalline silicon microelectrothermal actuator

A new method which just increases cold arm thickness of U-shaped polycrystalline silicon microelectrothermal actuator was proposed to efficiently amplify normal contact force caused by a rigid object placed away from the free end of the actuator. Finite element simulation results demonstrated that this method is better than the actuator array approach to amplify the normal contact force. As far as manufacturing difficulty and material consumption are concerned, the presented method is also more competitive than the array pattern. Considering amplifying effect on normal contact force, maximum equivalent stress on hot arm and equivalent stress at juncture of hot arm and cold arm, an actuator with hot arm thickness 2 μm and cold arm thickness about 7 μm is the relatively optimal configuration.