Study on the reliability of the mechanical shutter utilizing roll actuators

This paper handles a single approach to solve two major reliability issues of the previously proposed micro shutter using roll actuators. Material and structural change from Al/SiN_x to Mo/Mo improves the temperature stability of an aperture size by matching CTEs of bi-layer ideally. It is also effective to extend the rated lifetime of the shutter by eliminating a dielectric charging layer, SiNx. The measured temperature-invariant diameter of the Mo/Mo roll from 25°C to 80°C is compared with a dramatic change of the former Al/SiNx roll, which proves our approach effective. The rated lifetime reaches 200,000 (5 times higher than the previous work) just after applying Mo/Mo roll and 350,000 (1.7 times more) when dimples are added on it.