Fabrication and characterization of electrostatically driven silicon microbeams

Free standing single-crystal silicon cantilever beams were fabricated by a SCREAM-like process which uses dry etching. Typical dimensions are length 200 mu m, width 2-3 mu m, thickness 2-3 mu m. Cantilever beams were initially upward deflected by depositing a tungsten layer with a tensile stress. The electrostatic vertical actuation of the composite beam is investigated by biasing it with respect to the grounded substrate and lateral driving electrodes. A voltage of 10 V is sufficient to induce a large displacement of the beam free end up to 8 mu m. A precise positioning is obtained with a good repeatability. (C) 1998 Elsevier Science Ltd. All rights reserved.