Authors: M. Feldmann, A. Waldschik, S. Büttgenbach
Affilation: Institut for Microtechnology (IMT), Germany
Pages: 450 - 453
Keywords: micro actuators, synchronous micro motors, UV-depth lithography, polymer magnets, inorganic insulation layer
Electromagnetic micro actuators have reached a growing interest in micro technology in addition to commercial applications during the last years. Their basic construction exists of electric conductors and coil systems as well as of soft-magnetic and/or hard-magnetic materials that we were able to fabricate in additive technology via UV-depth lithography and electroplating. Moreover special micro composites were developed. This allowed the fabrication of micro magnets with arbitrary shape and properties. With these potential technologies we developed several synchronous motors with rotatory, 1D or 2D movements. The synchronous micro motors are brushless DC motors or stepper motors with electrical controlled commutation consisting of a stator and a rotor. The rotor is mounted onto the stator adjusted by an integrated guidance. Inside the stator different coil systems are realized, like double layer sector coils or special nested coils. The coil systems can be controlled by three or six phases depending on the operational modus. Furthermore special inorganic insulation layer were used, which reduced the system thickness, where by especially for the 2D devices four layer of electrical conductors can be realized. The smallest diameter of the rotatory motor is 1 mm and could be successfully driven. In addition first concepts for integrated magnetic position sensors were developed for closed loop control, which allows micro-/nano stepping and rotating.