Large tilt angle electrostatic force actuated micro-mirror

A large-angle electrostatic force actuated two-axis rotational micro-mirror has been proposed and demonstrated. A built-in air gap has been introduced in between the mirror and the bottom electrode to provide sufficient space for the rotation of the mirror. As a result, a large tilt angle has been achieved without using additional actuators. The gap was produced in such a way that the grounded mirror plate and the bottom electrode were made separately in different substrates and then combined. The measured tilt angles were as large as /spl plusmn/7.5/spl deg/ and /spl plusmn/6.4/spl deg/ in the x and y direction, and the pull-in voltages for the two axes were approximately 100 V. The micro-mirror was successfully used to steer an optical beam.