High-density array of micro-machined electrodes for neural stimulation

• US 20030195601A1
• Filed: 05/01/2002
• Published: 10/16/2003
• Est. Priority Date: 05/01/2001
• Status: Active Grant

• Current Assignee: Cortigent Incorporated, Second Sight Medical Products, Inc.
• Original Assignee: Second Sight Medical Products, Inc.
• Inventors: Greenberg, Robert, Zhou, Dao Min, Talbot, Neil, Hung, Andy, Judy, Jack
• Granted Patent: US 7,676,274 B2
• Time in Patent Office: Days
• US Class Current: 607/116
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/0526 Head electrodes A61N1/0551 takes precedence
• CPC Class Codes: A61N 1/0541 Cochlear electrodes
• CPC Class Codes: A61N 1/0543 Retinal electrodes
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes

Abstract

The present invention is a micro-machined electrode for neural-electronic interfaces which can achieve a ten times lower impedance and higher charge injection limit for a given material and planar area.

Claims

1. An electrode comprising:

an electrode base; and

a plurality of micromachined protuberances on said electrode base.

2. The electrode according to claim 1, wherein said protuberances are posts.

3. The electrode according to claim 2, wherein said post are hollow posts.

4. The electrode according to claim 1, wherein said protuberances are ridges.

5. The electrode according to claim 1, wherein said protuberances comprise platinum.

6. The electrode according to claim 1, wherein said protuberances comprise gold.

7. The electrode according to claim 1, wherein said protuberances comprise gold covered with platinum.

8. The electrode according to claim 1, wherein said protuberances comprise iridium.

9. The electrode according to claim 1, wherein said protuberances comprise iridium oxide.

10. The electrode according to claim 1, wherein said protuberances comprise titanium oxide.

11. The electrode according to claim 1, wherein said protuberances comprise a first metal and a second metal forming a hermetic seal over said first metal.

12. An electrode array comprising:

a lower flexible insulating layer;

a flexible conductive layer;

an upper flexible insulating layer including voids exposing portions of said flexible conductive layer; and

micromachined protuberances on said portions of said flexible conductive layer.

13. The electrode array according to claim 12, wherein at least one of said flexible insulating layers comprises polyimide.

14. The electrode array according to claim 12, wherein said flexible conductive layer comprises platinum.

15. The electrode array according to claim 12, wherein said flexible conductive layer comprises titanium.

16. The electrode array according to claim 12, wherein said protuberances comprise gold.

17. The electrode array according to claim 12, wherein said protuberances are posts.

18. The electrode array according to claim 17, wherein said post are hollow posts.

19. The electrode array according to claim 12, wherein said protuberances are ridges.

20. A method of increasing an electrode effective surface area comprising:

providing an electrode base; and

micromachining protuberances on the surface of said electrode base.

21. The method of claim 20, wherein said protuberances are micromachined from platinum.

22. The method of claim 20, further comprising the step of depositing said electrode base on an insulating layer.

23. The method according to claim 22, wherein said insulating layer is polyimide.

24. The method according to claim 20, further comprising the steps of:

depositing an upper insulating layer over said electrode; and

creating voids in said upper insulating layer over a portion of said electrode.

25. The method according to claim 20, wherein said step of micromachining comprises plating.

26. The method according to claim 20, wherein said step of micromachining comprises etching.

27. The method according to claim 20, wherein said step of micromachining comprises sputtering.

28. The method according to claim 20, wherein said step of micromachining comprises Ion-beam assisted deposition.

29. The method according to claim 20, wherein said step of micromachining comprises photolithographic techniques.

30. The method according to claim 20, wherein said step of micromachining comprises lift-off techniques.