Thin film implantable electrode and method of manufacture

A sheet (30) of polymeric material defines a cuff portion (A), a contact portion (B), and an interconnecting elongated lead portion (C). Using physical vapor deposition (PVD), chemical vapor deposition (CVD), or other thin film deposition techniques, a plurality of electrodes (12), contact pads (16), and interconnecting leads (14) are deposited on the base layer. An elastomer covering layer (18) is laminated to the base layer. The elastomeric covering layer is stretched along direction (24) before lamination, such that at least the cuff portion is elastomerically biased to curl into a spiral. Windows (20) are defined in the elastomeric portion to provide for electrical conduction between the electrodes (12) and nerve tissue about which the cuff electrode is wrapped. The electrodes are arced (FIG. 6) such that they are more recessed adjacent sides of the window than adjacent the center in order to provide a substantially uniform flux density across the electrode surface.