Fabrication and characterization of surface-modified dry electrode for monitoring biopotential

The low and stable contact impedance between the dry electrode and skin interfaces is crucial for the acquisition of high quality biopotential signal, especially for long-term recording. Building upon this fact, poly(3,4-ethylenedioxythiophene) (PEDOT), was introduced onto the surface of dry electrode to increase the active contact area and reduce contact impedance. Silicon-based dry electrode (6 mm x 6 mm) with pyramid-like micro-needles was fabricated by a low cost method: dicing plus etching. The electrode-to-skin contact impedance (ESCI) measured on subjects proved that dry electrodes with PEDOT surface-modification have better electrical properties than that without PEDOT surface-modification. Besides, PEDOT modification combined with the microfabrication process can provide a rapid, cost-effective and high-yield method to manufacture dry electrode.