MEMS FLEXIBLE SUBSTRATE NEURAL PROBE AND METHOD OF FABRICATING SAME

• US 20090299166A1
• Filed: 09/10/2007
• Published: 12/03/2009
• Est. Priority Date: 09/11/2006
• Status: Active Grant

• Current Assignee: University of Florida Research Foundation, Incorporated (State University System of Florida)
• Original Assignee: University of Florida Research Foundation, Incorporated (State University System of Florida)
• Inventors: Patrick, Erin E., Nishida, Toshikazu, Sanchez, Justin
• Granted Patent: US 8,170,638 B2
• Time in Patent Office: Days
• US Class Current: 600/378
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 2562/125 characterised by the manufacture of electrodes
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61B 5/268 containing conductive polymers, e.g. PEDOT:PSS polymers

Abstract

A method of fabricating a MEMS flexible substrate neural probe is provided. The method can include applying an insulation layer on a substrate, and depositing a plurality of metal traces on the insulation layer and electroplating each of the plurality of traces. The method also can include encapsulating the insulation layer and metal traces deposited thereon with an insulation layer. Additionally the method can include etching the insulation layer to form a plurality bond pad sites and probes to form a flexible ribbon cable having a plurality of bond pad sites disposed on a surface of the flexible cable and a plurality of neural probes extending from the flexible cable. The method further can include separating the substrate from the insulation layer and depositing insulation on each of the neural probes, each probe comprising insulated portion and exposed metallic tip. Moreover, the method can include cutting each of the exposed metallic tips, and plating each of the exposed metallic tips and each of the plurality of bond pad sites.

Claims

1. A MEMS flexible substrate neural probe, comprising:

a micro-machined flexible ribbon cable comprising a plurality of small-profile metal traces enclosed within a flexible insulation material; and

an array of probes extending outwardly from the flexible ribbon cable, each probe comprising an elongate conductor substantially enclosed by a surrounding insulator and having an exposed tip.

2. The neural probe of claim 1, further comprising a plurality of bond pad sites disposed on a surface of the flexible ribbon cable.

3. The neural probe of claim 1, wherein the flexible insulation material comprises polyimide insulation material.

4. The neural probe of claim 1, wherein the insulator comprises parylene-c.

5. The neural probe of claim 1, wherein each exposed tip of the array is micro-machined to have cross-sectional areas of less than 20×

50 μ

m².

6. The neural probe of claim 1, wherein each exposed tip of the array is electroplated.

7. The neural probe of claim 6, wherein the electroplated exposed tip is electroplated with one of gold (Au) or platinum (Pt).

8. The neural probe of claim 1, wherein the small-profile metal traces and conductors of the array comprises one of nickel (Ni) or platinum (Pt).

9. The neural probe of claim 1, wherein each probe of the array is no more than 2 mm in length.

10. The neural probe of claim 1, wherein the array comprises a plurality of planar arrays stacked to form a customizable three-dimensional (3-D) arrangement, the 3-D arrangement having a geometry suited to a predetermined neural structure.

11. A method of fabricating a MEMS flexible substrate neural probe, the method comprising:

applying an insulation layer on a substrate;

depositing a plurality of metal traces on the insulation layer and electroplating each of the plurality of traces;

encapsulating the insulation layer and metal traces deposited thereon with an insulation layer;

etching the insulation layer to form a plurality bond pad sites and probes to form a flexible ribbon cable having a plurality of bond pad sites disposed on a surface of the flexible cable and a plurality of neural probes extending from the flexible cable;

separating the substrate from the insulation layer and depositing insulation on each of the neural probes, each probe comprising insulated portion and exposed metallic tip;

cutting each of the exposed metallic tip; and

plating each of the exposed metallic tips and each of the plurality of bond pad sites.

12. The method of claim 11, wherein the step of applying the insulation layer comprises securing a polyimide layer to the substrate using a layer of Kapton tape.

13. The method of claim 12, wherein the step of applying comprises applying the polyimide layer over a silicon (Si) substrate.

14. The method of claim 11, wherein the step of depositing comprises sputtering and patterning metal traces on a polyimide layer.

15. The method of claim 11, where the step of depositing comprises sputtering traces of nickel (Ni) or platinum (Pt) on a polyimide layer.

16. The method of claim 11, wherein the step of encapsulating comprises depositing a polyimide layer over the insulation layer and metal traces deposited thereon.

17. The method of claim 11, wherein the step of etching comprises etching the insulation layer through reactive ion etching (RIE)

18. The method of claim 11, wherein the step of depositing insulation on each of the neural probes comprises depositing the insulation through vapor deposition.

19. The method of claim 18, wherein the step depositing insulation on each of the neural probes through vapor deposition comprises vapor depositing parylene-c on each of the neural probes.

20. The method of claim 19, wherein the step of plating each of the exposed metallic tips comprises electroplating each of the tips with gold (Au) or platinum (Pt) electroplating.

21. The method of claim 20, wherein the step of plating each of the exposed bond pad sites comprises plating each of the bond pad sites with gold (Au) or platinum (Pt) electroplating.