A multi-degree-of-freedom micromirror utilizing inverted-series-connected bimorph actuators

作者：Todd Shane T^*; Jain Ankur; Qu Hongwei; Xie Huikai

来源：Journal of Optics A: Pure and Applied Optics , 2006, 8(7): S352-S359.

DOI：10.1088/1464-4258/8/7/S10

• MEMS device
• micromirror
• bimorph actuator

A novel multi-degree-of-freedom electrothermal micromirror design that uses thermal inverted-series-connected (ISC) bimorph actuators is presented. The ISC bimorph actuators eliminate problems observed in previous designs that use single bimorph actuators. The micromirror can operate in one-dimensional (1D) piston-mode and two-dimensional (2D) tilt-mode. Analytical models for the piston-mode and tilt-mode actuations are shown and are compared to FEM simulation results. The device was fabricated using the AMI 1.5 mu m CMOS (complimentary metal-oxide semiconductor) process followed by a post-CMOS micromachining process for device release. The displacement versus temperature of the micromirror was measured experimentally over a range of temperatures and compared to analytical and FEM simulation results. Experimental results showed that the micromirror displaced by 56 mu m at an applied temperature 150 degrees C. The integrated polysilicon heaters were open-circuited during the post-CMOS microfabrication. The failure was caused by pinholes in the metal layers that allowed etchants to attack the polysilicon layer during post-CMOS microfabrication.

• 出版日期2006-7