Abstract
Current study reports a novel bioelectrode design based on a series of micro needle array for the measurement of surface biopotential. Without the pain sensation, the goal of these micro needles is to penetrate skin and minimize the variations in skin impedance, as well as body motion. Needle electrodes with high depth definition was fabricated and tested on de-haired rat skin surface for impedance measurements. Experiment results showed a prominent reduction in electrode s impedance when compared with traditional silver/silver-chloride electrodes. A quasi-linear relationship was also observed between electrode surface area and measured skin/electrode impedance.