Lorentz force actuation of flexible thin-film aluminum microstructures

Microcoils are less efficient due to the scale effect, but if a permanent magnet is used, the result is a quite scale-independent magnetic field strength. 2D-microstructures of various shapes have been etched out from a 1 μm aluminium thin-film. These structures are locally released from the wafer by undercut etching. By sending an electric current through them, a Lorentz force component is induced in some sections, resulting in deformation of the thin-film structure. First, different shapes of 1-turn coils are presented. The arrangement of vertical and parallel magnetic field is discussed. Micromachine fabrication using IC thin-film, lithography and etching technology is presented. An x-y table was built as an application example for the use of Lorentz force in micromachines. For protection and the ease of handling the microactuators are packaged into a standard IC case. As examples of further applications of Lorentz force actuators, a micromirror device, a ciliary motion system and microrelays are discussed