In manufacturing implantable electrodes several precautions have to be observed to avoid mechanical stress and therefore to avoid failure: The wires are spiralized, a silicone tube is pulled over them and they are fixed in spiralled position with silicone glue. In most cases stainless steel wires are used.
Complete electrode sets are assembled in the cleanroom, to avoid special cleaning processes. There are single- and multipole electrodes, ring-, ball and plate-tipped ones, cuff electrodes, depending on the application. There are electrodes for electrostimulation as well as sensing electrodes.