Magnetostrictive micro mirrors for an optical switch matrix

Abstract

We have developed a wireless-controlled compact optical switch by silicon micromachining techniques with DC magnetron sputtering. For the optical switching operation, micro mirror is designed as cantilever shape size of 5mm x 800 mu x 50 mu m. TbDyFe film is sputter-deposited on the upper side of the mirror with the condition as: Ar gas pressure below 1.2x10(-9) torr, DC input power of 180W and heating temperature of up to 250 C for the wireless control of each component. Mirrors are actuated by externally applied magnetic fields for the micro application. Applied beam path can be changed according to the direction and the magnitude of applied magnetic field. Reflectivity changes, M-H curves and X-ray diffractions of sputtered mirrors are measured to determine magneto-optical, magneto-elastic properties with variation in sputtered film thickness. The deflected angle-magnetic field characteristics of the fabricated mirror are measured.