Electrode structure and methods for making and using same

• US 20050154436A1
• Filed: 12/17/2004
• Published: 07/14/2005
• Est. Priority Date: 12/19/2003
• Status: Active Grant

• Current Assignee: Heraeus Deutschland GmbH & Co. KG (Heraeus Holding GMBH)
• Original Assignee: WC Heraeus GmbH (Heraeus Holding GMBH)
• Inventors: Specht, Heiko, Kruger, Frank
• Granted Patent: US 7,653,439 B2
• Time in Patent Office: Days
• US Class Current: 607/116
• CPC Class Codes: A61N 1/0541 Cochlear electrodes
• CPC Class Codes: A61N 1/0543 Retinal electrodes
• CPC Class Codes: Y10T 428/1352 Polymer or resin containing [i.e., natural or synthetic]
• CPC Class Codes: Y10T 428/1355 Elemental metal containing [e.g., substrate, foil, film, coating, etc.]

Abstract

An electrode structure made of noble metal or a noble metal alloy having a thickness of ≦100 μm is provided for implants. The electrode structure has an electrode core made of gold, silver, copper, or an alloy of at least two of these elements, and the electrode core is completely encased by a first coating, which is formed from platinum, iridium, or ruthenium.

Claims

1. An electrode structure (10) for implants, comprising a noble metal or a noble metal alloy having a thickness of ≦

100 μ

m, wherein the electrode structure (10) has an electrode core (12) comprising an element selected from the group consisting of gold, silver, copper, and alloys of at least two of these elements, and wherein the electrode core (12) is encased completely by a first coating (13;

13a, 13b) comprising at least one element selected from the group consisting of platinum, iridium, and ruthenium.

2. The electrode structure (10) according to claim 1, wherein the electrode core (12) has a thickness in a range of about 5 μ

m to 99.8 μ

m.

3. The electrode structure (10) according to claim 1, wherein the first coating (13, 13a, 13b) has a thickness in a range of about 100 nm to about 5 μ

m.

4. The electrode structure (10) according to claim 1, wherein the electrode structure (10) has a thickness in a range of about 7 μ

m to about 30 μ

m.

5. The electrode structure (10) according to claim 1, wherein a second coating, which is different from the first coating (13, 13a, 13b) and which comprises at least one element selected from the group consisting of ruthenium, ruthenium oxide, iridium, iridium oxide, platinum, or titanium nitride, is formed on a side of the first coating (13, 13a, 13b) facing away from the electrode core (12).

6. The electrode structure (10) according to claim 5, wherein the second coating covers only parts of the first coating (13, 13a, 13b).

7. A method for producing the electrode structure (10) according to claim 1, comprising:

a) coating an electrically insulating surface (14a) of a substrate (14) with a metal layer (15), then coating the metal layer (15) with a photoresist (16), and structuring the photoresist (16),

b) galvanically generating a first part (13a) of the first coating on regions of the metal layer (15) exposed by the structured photoresist,

c) galvanically forming the electrode core (12) on the first part (13a) of the first coating,

d) then removing the structured photoresist (16) from the metal layer (15),

e) removing the metal layer (15) from the electrically insulating surface (14a) of the substrate (14) in regions not covered by the first part (13a) of the first coating,

f) galvanically coating part of the electrode core (12) still free up to now from the first coating with a second part (13b) of the first coating,

g) detaching the electrode structure (10) including the metal layer (15) from the electrically insulating surface (14a) of the substrate (14), and

h) then removing the metal layer (15) from the electrode structure (10).

8. The method according to claim 7, wherein the electrically insulating surface (14a) of the substrate (14) comprises glass or plastic.

9. The method according to claim 7, wherein the metal layer (15) comprises copper or gold.

10. A method for producing the electrode structure (10) according to claim 1, comprising:

a) providing an electrically insulating surface (14a) of a substrate (14) with a mask, and forming a metal layer (15) by cathode sputtering or vapor deposition on regions of the electrically insulating surface (14a) not covered with the mask,

b) generating a first part (13a) of the first coating by cathode sputtering or vapor deposition on the metal layer (15),

c) then forming the electrode core (12) by cathode sputtering or vapor deposition on the first part (13a) of the first coating,

d) then removing the mask,

e) galvanically coating at least part of the electrode core (12) still free up to now from the first coating (3a, 3b) with a second part (13b) of the first coating, and

f) then detaching the electrode structure (10) from the electrically insulating surface (14a) of the substrate (14) such that the metal layer (15) is removed.

11. The method according to claim 10, wherein the electrically insulating surface (14a) of the substrate (14) comprises glass or plastic.

12. The method according to claim 10, wherein the metal layer (15) comprises copper or gold.

13. A method for producing the electrode structure (10) according to claim 1, comprising:

a) coating an electrically insulating surface (14a) of a substrate (14) with a structured metal layer, which forms a first part (13a) of the first coating,

b) providing the first part (13a) of the first coating with a mask, and forming the electrode core (12) by cathode sputtering or vapor deposition only on the first part (13a) of the first coating,

c) then galvanically coating part of the electrode core (12) still free up to now from the first coating (3a) with a second part (13b) of the first coating, and

d) then detaching the electrode structure (10) from the electrically insulating surface (14a) of the substrate (14).

14. The method according to claim 13, wherein the electrically insulating surface (14a) of the substrate (14) comprises glass or plastic.

15. The electrode structure (10) according to claim 1, in a form selected from the group consisting of stimulation electrodes, cochlear electrodes, and retinal electrodes.