A flexible circuit electrode array with more than one layer of metal traces comprising: a polymer base layer； more thanone layer of metal traces, separated by polymer layers, deposited on said polymer base layer, including electrodes suitable to stimulate neural tissue； and a polymer top layer deposited on said polymer base layer and said metal traces. Polymer materials are useful as electrode array bodies for neural stimulation. They are particularly useful for retinal stimulation to create artificial vision, cochlear stimulation to create artificial hearing, or cortical stimulation many purposes. The pressure applied against the retina, or other neural tissue, by an electrode array is critical. Too little pressure causes increased electrical resistance, along with electric field dispersion. Too much pressure may block blood flow.
