A Photosensitive Polyimide-SiO2 Bimorph based Electrothermal Micromirror with High Impact Resistance

Resistance to impact damage is highly favored in hand-held optical scanning applications. In this work, a lateral-shift-free (LSF) electrothermal micromirror with high impact resistance is proposed and fabricated. The high impact resistance is achieved by employing photosensitive polyimide (PSPI) and SiO
2
to construct the bimorph actuators. Experiments show that compared with previous LSF electrothermal micromirrors, the impact resistance is increased by about 20 times. In addition, the power efficiency of the new micromirror is doubled due to the good thermal isolation provided by PSPI. This new type of micromirrors is a promising candidate in hand-held and long-time scanning applications, including LIDAR and optical endoscopic probes.