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The ability to structure and sculpture materials is the foundation of micro structure engineering. This presentation focus on structuring a multilayer micro actuator consisting of poly(vinylidenefluoride-tetrafluoroethylene) P(VDF-TrFE) and evaporated aluminium electrodes. The actuator structure is designed for the EU sponsored Intelligent Small World Autonomous Robots for Micro-manipulation (I-SWARM) project, with the objective to present a swarm of 1000 operational (3x3 mm) robot. As substrate material a single sided flexible printed circuit board (FPC) is used. On the polymer side of the FPC the active actuator stack is built with a multilayer thin film technique. The actuator stack has ten active layers of P(VDF-TrFE) sandwiched between phase and ground electrodes. The polymer layers are applied by spin coating and the electrodes are resistively evaporated by the use of shadow masks. In order to obtain electrical contact between the electrode layers, the module has to be dry etched. Attempts have been done to etch the P(VDF-TrFE) in a RIE and in an ICP. Since each electrode mask is slightly different at the contact areas, the staircase like layer structures are exposed after the dry etch step. These can be contacted from the top with conductive adhesive by screen printing. A modified Bosch process in the ICP resulted in complete removal of all P(VDF-TrFE) not covered by the aluminium electrodes. After the conductive adhesive was applied, the measured capacitance showed good agreement with the theoretical figures, an indication that the ICP etch resulted in good electrical contact with few polymer residuals left on the electrode surface. |