Electrostatic devices for particle microhandling

Devices for handling microparticles using an AC electric field are proposed and experimentally validated. With the application of balanced multiphase high voltages in the 0.2 kV/sub p-p/-2 kV/sub p-p/ range to a series of encased parallel electrodes with a typical center-to-center pitch width of 400 /spl mu/m, particles on a thin protecting and insulating film become charged and are conveyed by the created traveling field. Devices with various novel transportation and manipulation features, utilizing multiphase AC electric fields that instantly generate particle driving forces, have been designed and produced. Their features include newly developed methods for particle conveyance, smoothing, grouping and sorting, as well as two-dimensional handling. Traced particle conveyance characteristics have been studied under application of three and six-phase voltages with three different voltage wave profiles and also in diverse environments. Various particle materials with a 5-400 /spl mu/m diameter range have been experimentally examined; Fe, Al, glass and plastic spheres showed the best performances.