Low cost and large deflection angle polymer MEMS mirror using glass substrate

In this paper, we propose a polymer MEMS mirror device which has the futures of the large deflection angle and the low cost fabrication. Many conventional MEMS mirror devices have been composed of Si wafer and, the expensive dry etching equipment has been necessary when etching the Si substrate. Then, we propose new composition and the novel fabrication method without the dry etching process by using the inexpensive glass substrate. Also, the torsion bar is composed of a photosensitive polymer that is a low rigid material and can be easily fabricated by the photolithography process. A multilayer wiring process is examined so that the low current actuation and the large deflection angle is attained. The fabricated device showed the large optical deflection angle of more than ±40 degrees at the current of ±16mA when the torsion bar length was 1800μm. The variation of the optical deflection angle was within 0.8 degrees at the 10⁶ times repeatability test.