Porous silicon as an inherent surface enlarging layer for improved electrode performance in stimulation and recording applications

The performance of doped silicon and porous silicon as a new electrode material in neurophysiological applications is investigated. By increasing the surface area of adopted silicon region through anodisation in hydrofluoric acid it was found that the impedance parameters of the electrode were considerably improved. Impedance spectra of bare silicon electrodes, porous electrodes and platinum electroplated porous silicon electrodes are presented. It was found that porous silicon electrodes display a 2.5 times higher capacitance and the platinum electroplated porous silicon electrode displayed a 5 times higher capacitance when compared to the corresponding planar doped silicon electrode.