Dong Hyun Kim
The Journal of Mechanical Science and Technology, vol. 23, no. 6, pp.1536-1543, 2009

Abstract : This paper reports the design of a novel twisting-type micromirror actuation system. The actuating mechanism for driving the micromirror combines two paralleled bimorph actuators bending in opposite directions for rotational control of the micromirror. Each actuator is structured by gold and silicon dioxide or nickel and silicon nitride thin films with embedded polysilicon line heaters. With a size of only 15μm in width, 1.3μm in thickness, and 100μm in length, two bimorph actuators can result in a vertical displacement of 25μm at 10 volts dc with the span of 120μm, and thus the micromirror can rotate by angles over 20°, which is a significant improvement, compared to conventional tilting-type micromirrors.

Keyword : Micromirror; MEMS; Bimorph thermal actuator; Twisting-mode