Title :
Static and electrically actuated shaped MEMS mirrors
Author :
Mi, Bin ; Smith, David A. ; Kahn, Harold ; Merat, Frank L. ; Heuer, Arthur H. ; Phillips, Stephen M.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Case Western Reserve Univ., Cleveland, OH, USA
Abstract :
A novel digitally-actuated shaped micromirror for on-off optical switch applications is described. Reflective static spherical mirrors were designed and fabricated using conventional surface micromachining and the MultiPoly process, a technique for depositing multilayers of LPCVD polysilicon in order to control the overall stress and stress gradient. The resulting mirrors were measured to have radii of curvature of approximately 9 mm in agreement with design predictions. Based upon these static mirrors, an actuatable micromirror (diameter=500 μm, static radius curvature=6.4 mm) was designed for snap action. This mirror was simulated using an electromechanical coupled-field model and fabricated using the MultiPoly process. Its performance was measured dynamically using an interferometer. A curved-to-flat digital actuation of the mirror was successfully achieved with a pull-in voltage of 38 V.
Keywords :
chemical vapour deposition; micromachining; micromechanical devices; micromirrors; optical switches; 38 V; 500 micron; LPCVD polysilicon; MultiPoly process; actuatable micromirror; curvature modulation; curvature radii; curved-to-flat digital actuation; deposition; electromechanical coupled-field model; interferometer; microelectromechanical systems; optical switch applications; reflective static spherical mirrors; static mirrors; stress gradient; surface micromachining; Displays; Micromechanical devices; Micromirrors; Mirrors; Nonhomogeneous media; Optical arrays; Optical design; Optical interferometry; Optical switches; Stress;
Journal_Title :
Microelectromechanical Systems, Journal of
DOI :
10.1109/JMEMS.2004.839022
