RECESSED ELECTRODES FOR FLEXIBLE SUBSTRATES
The present invention relates to a metal mesh transparent electrode with improved planarization and reflection characteristics. The metal mesh transparent electrode according to a first embodiment of the present invention comprises: a substrate ( 10 ); a metal mesh layer ( 20 ) formed in a mesh shape having a plurality of through holes and disposed on one surface of the substrate ( 10 ); and a buffer layer ( 30 ) covering the metal mesh layer ( 20 ) to be filled in the through holes.
1 . An implantable medical electrode for stimulation or sensing, wherein the electrode comprises:
an electrically insulating substrate having a substrate surface, wherein the substrate surface comprises at least one recess, wherein the at least one recess comprises:
a bottom surface arranged at a first distance to the substrate surface and at least one wall connecting the bottom surface to the substrate surface;
a conducting element arranged in contact with the bottom surface;
a layer of conductive polymer in contact with the conducting element thus forming an electrical connection with the conducting element when a current is applied.
2 . The implantable medical electrode of claim 1 wherein the layer of conductive polymer has a maximum thickness that is less than or equal to the substrate surface.
3 . The implantable medical electrode of claim 1 wherein the substrate is flexible.
4 . The implantable medical electrode of claim 1 wherein the layer of conductive polymer protrudes above the substrate surface.
5 . The implantable medical electrode of claim 1 wherein the layer of conductive polymer has a charge storage capacitance ranging from 1 to 400 mC/cm 2 .
6 . The implantable medical electrode of claim 1 further comprising a connecting element capable of connecting the conducting element to a current source.
7 . The implantable medical electrode claim 1 wherein the layer of conductive polymer comprises PEDOT.
8 . The implantable medical electrode of claim 4 wherein the layer of conductive polymer protruding above the substrate surface comprises a pattern of lines.
9 . The implantable medical electrode of claim 4 wherein the layer of conductive polymer protruding above the substrate surface also extends laterally beyond the recess.
10 . The implantable medical electrode of claim 1 wherein the at least one recess has a geometry selected from the group consisting of a cylinder, a cube, a cuboid, a trapezoid, a square, a circle, a rectangle, and a triangle.
11 . The implantable medical electrode of claim 1 comprising a plurality of recesses arranged in a pattern throughout the electrode.
12 . The implantable medical electrode of claim 1 wherein the pattern is selected from the group consisting of a grid, axial lines, radial lines.
13 . The implantable medical electrode of claim 1 wherein the substrate comprises a material selected from the group consisting of a polymer, a natural rubber, a natural fiber, and a ceramic.
14 . The implantable medical electrode of claim 1 wherein the substrate comprises a polymer selected from the group consisting of a polyester, a polyethylene foam, a cellulose rayon non-woven material, polyethylene vinyl acetate, polyurethane, and polyimide.
15 . The implantable medical electrode of claim 1 wherein the conducting element comprises a metal selected from the group consisting of platinum, gold, nitinol, and alloys thereof.
16 . An implantable medical device comprising the implantable medical electrode of claim 1 .
17 . A method of manufacturing an implantable medical electrode for stimulation or sensing, comprising steps of
a. providing an electrically insulating substrate having a substrate surface, wherein the substrate surface comprises at least one recess, wherein the at least one recess comprises:
a bottom surface arranged at a first distance to the substrate surface and at least one wall connecting the bottom surface to the substrate surface; and a conducting element arranged in contact with the bottom surface;
b. forming a layer of conductive polymer in contact with the conducting element thus forming an electrical connection with the conducting element when a current is applied, wherein the layer of conductive polymer has a maximum thickness that is less than or equal to the substrate surface.
18 . The method of claim 17 wherein the forming step comprises electropolymerization.
19 . The method of claim 17 wherein providing the substrate comprises forming a cavity in the substrate by selectively removing material from the substrate.
20 . The method of claim 17 wherein the layer of conductive polymer has a maximum thickness that is less than or equal to the substrate surface.
21 . The method of claim 17 wherein the substrate is flexible.
22 . The method of claim 17 wherein the layer of conductive polymer protrudes above the substrate surface.
23 . The method of claim 17 wherein the layer of conductive polymer has a charge storage capacitance ranging from 1 to 400 mC/cm 2 .
24 . The method of claim 17 wherein a connecting element connects the conducting element to a current source.
25 . The method of claim 17 wherein the layer of conductive polymer comprises PEDOT.
26 . The method of claim 17 wherein the layer of conductive polymer protruding above the substrate surface comprises at least one additional layer or pattern of conductive polymer.
27 . The method of claim 17 wherein the at least one recess has a geometry selected from the group consisting of a cylinder, a cube, a cuboid, and a trapezoid.
28 . The method of claim 17 wherein the substrate surface comprises a plurality of recesses arranged in a pattern.
29 . The method of claim 28 wherein the pattern is selected from the group consisting of a grid, axial lines, radial lines.
30 . The method of claim 17 wherein the substrate comprises a material selected from the group consisting of a polymer, a natural rubber, a natural fiber, and a ceramic.
31 . The method of claim 17 wherein the substrate comprises a polymer selected from the group consisting of a polyester, a polyethylene foam, a cellulose rayon non-woven material, polyethylene vinyl acetate, polyurethane, and polyimide.
32 . The method of claim 17 wherein the conducting element comprises a metal selected from the group consisting of platinum, gold, nitinol, and alloys thereof.
33 . A method of treatment, comprising contacting a human patient with the implantable medical electrode according to claim 1 and delivering an electrical signal to said patient.
34 . A diagnostic method, comprising contacting a human patient with the implantable medical electrode of claim 1 and detecting an electrical signal from the patient.
35 . The implantable medical electrode of claim 4 wherein the layer of conductive polymer protrudes above the substrate surface at a distance of from 0.1 to 2.0 μm.
36 . The implantable medical electrode of claim 4 wherein the layer of conductive polymer protruding above the substrate surface has a top view geometry of at least one selected from the group consisting of a circle, a square, a rectangle, a triangle, or a trapezoid.