Advanced LIGA technology for the integration of an electrostatically controlled bearing in a wobble micromotor

This work concerns the alleviation of friction in a novel design of multistator electrostatic wobble motor. The output torque and the kinematic accuracy of this device are limited by the sliding friction between the rotor and the top surface of the bearing. A solution for an axial bearing has been developed using an advanced LIGA technique to integrate polymethylmethacrylate (PMMA) cylinders into nickel micro structures. A new version of the micromotor has been fabricated, utilizing an axial electrostatic field to hold the rotor against an engineered sliding surface. The integrated bearing stabilizes the rotor and potentially permits operation in liquid environments by sealing the stator electrodes. [334] Index Terms - Electrostatic bearing, electrostatic motor, LIGA process, micromotor, wobble motor.