Flexible implantable electrode arrangement and production method
A flexible implantable electrode arrangement includes an electrically insulating carrier structure of a first polymer material, an electrically conductive layer, and an electrically insulating cover layer of a second polymer material. The electrically conductive layer includes an electrically conductive carbon fiber layer. The electrically conductive layer integrally forms an implantable electrode, a conductor track connected to the implantable electrode, and a contact pad. The electrically insulating cover layer at least partially covers the electrically conductive layer.
1 . A flexible implantable electrode arrangement, comprising:
an electrically insulating carrier structure comprising a first polymer material;
an electrically conductive layer comprising an electrically conductive carbon fiber layer, the electrically conductive layer integrally forms an implantable electrode, a conductor track connected to the implantable electrode, and a contact pad, the electrically conductive carbon fiber layer is a structured mat made from a woven fabric, knitted fabric, or non-woven fabric, the structured mat is structured to remove a plurality of portions of the electrically conductive carbon fiber layer to form the implantable electrode, the conductor track, and the contact pad in a single piece of the electrically conductive carbon fiber layer with no interface between the implantable electrode and the conductor track; and
an electrically insulating cover layer comprising a second polymer material, the electrically insulating cover layer at least partially covering the electrically conductive layer.
2 . The flexible implantable electrode arrangement of claim 1 , wherein the first polymer material and/or the second polymer material comprise at least one of: polyimide, polyethylene terephthalate, polyethylene, polycarbonate, polyvinyl chloride, polyamide, polytetrafluoroethylene, polymethyl methacrylate, polyether ether ketone, polysulfone, Poly(p-xylylene), polydimethylsiloxane, and/or polypropylene.
3 . The flexible implantable electrode arrangement of claim 1 , wherein the electrically conductive carbon fiber layer is produced from a pyrolyzed polymer material.
4 . The flexible implantable electrode arrangement of claim 1 , wherein the electrically insulating cover layer and/or the electrically insulating carrier structure at least partially penetrates into the electrically conductive carbon fiber layer.
5 . A method for producing an implantable electrode arrangement, comprising:
providing an electrically insulating carrier structure comprising a first polymer material;
applying an electrically conductive layer comprising an electrically conductive carbon fiber layer on the electrically insulating carrier structure, the electrically conductive layer integrally forms an implantable electrode, a conductor track connected to the implantable electrode, and a contact pad, the electrically conductive carbon fiber layer is a carbon fiber mat made from a woven fabric, knitted fabric, or non-woven fabric;
structuring the carbon fiber mat into a structured mat by removing a plurality of portions of the electrically conductive carbon fiber layer to form the implantable electrode, the conductor track, and the contact pad in a single piece of the electrically conductive carbon fiber layer with no interface between the implantable electrode and the conductor track; and
applying an electrically insulating cover layer to at least partially cover the electrically conductive layer, the electrically insulating cover layer comprises a second polymer material.
6 . The method of claim 5 , wherein the electrically insulating carrier structure is provided on a substrate in a form of a precursor of the first polymer material that has not cured or has only cured in part.
7 . The method of claim 5 , wherein the carbon fiber mat is structured using an etching mask layer by wet etching or dry etching.
8 . The method of claim 5 , wherein the carbon fiber mat is structured without a mask directly by laser ablation.
9 . The method of claim 5 , wherein the carbon fiber mat is produced by pyrolysis of a polymer.
10 . The method of claim 9 , wherein the polymer is polyacrylonitrile.
11 . The method of claim 5 , wherein the electrically insulating cover layer is applied on the electrically conductive carbon fiber layer in a form of a precursor of the first polymer material that has not cured or has only cured in part.
12 . The method of claim 5 , wherein the electrically insulating cover layer is deposited in a spin-on process, by atomization, by spray coating, by vapor deposition, or in a potting process.
13 . The method of claim 5 , wherein the first polymer material and/or the second polymer material comprise polyimide and/or polydimethylsiloxane.
14 . The method of claim 5 , wherein the carbon fiber mat is produced by an electrospinning process.
15 . The method of claim 5 , further comprising activating the first polymer material by an oxygen plasma prior to applying the second polymer material.
16 . The flexible implantable electrode arrangement of claim 1 , wherein the structured mat is a planar layer consisting of carbon.
17 . The method of claim 5 , wherein the structured mat is a planar layer consisting of carbon.