Electrostatic curved electrode actuators

In this paper, the design, fabrication, and first experimental results of electrostatic curved electrode actuators are addressed. The actuator design is based upon the deformation of a movable micromechanical structure by electrostatic forces using a fixed curved electrode. When a voltage is applied, an electrostatic force is created that will deform the free structure along the outline of the fixed curved electrode. To investigate the basic phenomena of this type of actuators, research has been focused on cantilever beam structures. For the shape of the curved electrode simple polynomials, normalized to the maximal deflection, have been used. A theory is presented, describing the static behaviour of this type of actuators. Devices are fabricated from polysilicon by surface micromachining techniques. Displacements of several tens of micrometers and forces of several FN can be generated for cantilever beams with a length of several hundred micrometers