Design and fabrication of electromagnetic micromirror with bulk silicon mirror plate and aluminum spring

We have designed and fabricated an electromagnetic micromirror with a flat mirror plate capable of large angular deflection. Single-crystal silicon is used as a mirror plate to obtain an optically flat reflective surface. By a combination of surface and bulk micromachining processes, the single-crys tal silicon mirror plate is connected to the substrate via an aluminum spri ng, which occupies a relatively small area without compromising the complia nce. The proposed fabrication process can be applied to the fabrication of devices in which a flat moving part is supported by a compliant spring stru cture. Nickel electroplated onto the mirror plate enables a mirror rotation angle of up to 84.8 degrees by applying an external magnetic field vertica l to the substrate. This designed structure can be used individually or as an array in microphotonic applications.