Transverse electromagnetic microactuators using electroplated planar coil driven by symmetric twin magnets

Abstract

In this paper, we present an electromagnetic microactuator that uses an electroplated copper coil on a p(+)-silicon diaphragm with symmetric twin magnets. The microactuator generates a vertical motion of the diaphragm using the radial components of the magnetic field on the coil plane. To guide and concentrate the magnetic field in the radial direction, we propose a new microactuator structure with symmetric twin magnets. The microactuator shows values of resonant frequency and quality factor in the ranges of 10.51 +/- 0.22 kHz and 46.6 +/- 3.3, respectively. The twin magnet microactuator generates the maximum peak-to-peak amplitude of 4.4 mu m for an AC rms current of 26.8 mA, showing 2.4 times larger amplitude than the single magnet microactuator.