A cochlear stimulation device comprising an electrode array designed to
provide enhanced charge injection capacity necessary for neural
stimulation. The electrode array comprises electrodes with high surface
area or a fractal geometry and correspondingly high electrode capacitance
and low electrical impedance. The resultant electrodes have a robust
surface and sufficient mechanical strength to withstand physical stress
vital for long term stability. The device further comprises wire traces
having a multilayer structure which provides a reduced width for the
conducting part of the electrode array. The cochlear prosthesis is
attached by a grommet to the cochleostomy that is made from a single
piece of biocompatible polymer. The device, designed to achieve optimum
neural stimulation by appropriate electrode design, is a significant
improvement over commercially available hand-built devices.