Implantable microelectrode

Abstract

A miniature, electrically-insulated multi-conductor electrical cable suitable for implantation in living bodies and readily connected to sensors or electrodes, and implantable microelectrodes attached to such cables. Individual electrical conductors are coated with at least one layer of, insulating material and stranded together, or optionally bound together by an additional layer of insulating material which is compatible with implantation in living bodies. The individual conductors are separated from one another in terminal portions of the cable and are held by a ribbonizing resin at a predetermined pitch to facilitate connection of each of the conductors. The terminal portions may define microelectrodes. Another microelectrode includes an electrically conductive electrode core member sharpened and coated with a thin layer of a dielectric material. An extremely small area of the core at the sharpened point is exposed by ablating the dielectric material by the use of an ultraviolet laser beam scanned over the material. Multiple conductor microelectrodes may also be supported within a hollow needle or in flat ribbon configuration, with openings in dielectric material defining active electrode sites. Multiple active electrode sites may be defined on a microelectrode accompanied by an integrated circuit after connection of the integrated circuit to a multiconductor cable.