A micro shutter for applications in optical and thermal detectors

This paper reports on an electrostatically driven micro shutter for optical or thermal detectors. The design is based on a surface micromachined micromotor with rotor diameters of 800 /spl mu/m and 1200 /spl mu/m, respectively. An aperture of 100/spl times/200 /spl mu/m/sup 2/ or 200/spl times/300 /spl mu/m/sup 2/ is etched from the backside of the substrate. Parts of the rotor and the whole backside are coated with a thin gold layer to reduce IR transmittance. The shutter is applied in a pyroelectric detector and the operation is characterized. Minimum driving voltages are 35 V to 60 V and the number of revolutions ranges from 0 rpm up to more than 7000 rpm.