Electrothermally-driven long stretch micro drive with monolithic cascaded actuation units in compact arrangement

An electrothermally-driven long stretch micro drive (LSMD) is presented for in-plane rectilinear motions in hundreds of micrometers with very compact arrangement. High output performance (output displacements over device area excluding electrical contact pads) of 200 /spl mu/m/mm/sup 2/ has successfully achieved for devices made of 10/spl sim/12 /spl mu/m thick electroplated nickel. The proposed device (N=5) features large output displacements with low operation temperatures (<350/spl deg/C) and driving voltages (<4 volts). It can be operated up to 100 Hz at 3 volts without displacement degradations. Experiments and simulations are conducted to verify two design issues, bent beam angle and constraint bar width, with good agreements. The output displacements can be effectively magnify by cascading more actuation units in cascaded structures of the micro drive.