Wireless micro swimming machine with magnetic thin film

As the magnetic micro-machines are driven by a magnetic field, they require no power supply cables, no batteries, and no controlling systems on the machine body. We fabricated the spiral-type micro-machine ( outer diameter; 0.14 mm, length; 1.0 mm) by a tungsten wire (phi 20 mu m). NdFeB film magnet was deposited on the spiral-machine by the PLD method. In the experiment, the wireless micro-machine swam at the speed of 0.2 - 1.6 mm/s. This result indicated that the spiral shape was suitable for miniature swimming machine. (C) 2003 Elsevier B. V. All rights reserved.