Fabrication of Three-dimensional Micro-actuators with Polypyrrole/Gold Bi-layer Structure

Abstract

Three-dimensional micro-actuators consisting of a polypyrrole (PPy)/Au bi-layer, were fabricated by Al anodizing, laser irradiation, and electrochemical techniques. Aluminum specimens covered with porous type oxide films were irradiated with a pulsed Nd-YAG laser to remove the oxide films locally. Then an Au layer and a PPy layer were deposited at the area where the film had been removed. Finally, the specimens were immersed in a NaOH solution after connection with or without a Pt plate to separate PPy/Au actuators from the Al substrate and anodic oxide film. The PPy layer did not lose its electroconductivity when the specimen was immersed in NaOH solution after connection with a Pt plate, although the conductivity was lost after immersion of the specimen alone. Immersion with the Pt connection suppressed the PPy reduction and enabled the fabrication of PPy/Au actuators. Three-dimensional PPy/Au bi-layer micro-actuators were fabricated using column Al specimens. They are much more flexible than PPy/Au/resin three-layer actuators described in a previous paper.