METHOD FOR ENHANCING GROWTH OF CARBON NANOTUBES

• US 20100092369A1
• Filed: 10/14/2008
• Published: 04/15/2010
• Est. Priority Date: 10/14/2008
• Status: Active Grant

• Current Assignee: Brother International Corporation (Brother Industries Limited)
• Original Assignee: Brother International Corporation (Brother Industries Limited)
• Inventors: PARSAPOUR, FARZAD
• Granted Patent: US 9,346,679 B2
• Time in Patent Office: Days
• US Class Current: 423/447.1
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01B 2202/08 Aligned nanotubes
• CPC Class Codes: C01B 2202/34 Length
• CPC Class Codes: C01B 32/162 characterised by catalysts

Abstract

A method for fabricating a plurality of carbon nanotube structures having enhanced length is disclosed. Several steps are involved in this method. First, a substrate is provided. Next, a non-catalytic metal layer is formed on the substrate. Then, a catalytic metal layer is formed on the non-catalytic metal layer. After that, the catalytic metal layer is subjected to ultrasonication and exposure to water. Finally, the plurality of carbon nanotube structures is formed on the substrate in the presence of the catalytic metal layer. In this embodiment, the ultrasonication and exposure to water step includes submerging the catalytic metal layer in a liquid bath, ultrasonicating the catalytic metal layer and the liquid bath, and exposing the catalytic metal layer to water.

Claims

1. A method for fabricating a plurality of carbon nanotube structures having enhanced length, the method comprising:

providing a substrate;

forming a non-catalytic metal layer on the substrate;

forming a catalytic metal layer on the non-catalytic metal layer;

subjecting the catalytic metal layer to an ultrasonication and exposure to water step, the ultrasonication and exposure to water step comprising;

submerging the catalytic metal layer in a liquid bath;

ultrasonicating the catalytic metal layer and the liquid bath; and

exposing the catalytic metal layer to water; and

after the ultrasonication and exposure to water step, forming the plurality of carbon nanotube structures on the substrate in the presence of the catalytic metal layer.

2. The method of claim 1,

wherein the catalytic metal layer is ultrasonicated before the catalytic metal layer is exposed to water.

3. The method of claim 2,

wherein the catalytic metal layer is exposed to deionized water.

4. The method of claim 1,

wherein the catalytic metal layer is exposed to water before the catalytic metal layer is ultrasonicated.

5. The method of claim 1,

wherein the liquid bath is an aqueous solution.

6. The method of claim 1,

wherein the liquid bath is water, and

wherein the catalytic metal layer is simultaneously ultrasonicated and contacted with water.

7. The method of claim 1,

wherein the liquid bath is a non-aqueous solution.

8. The method of claim 1,

wherein the liquid bath includes an alcohol.

9. The method of claim 1,

wherein the liquid bath includes dimethyl sulfoxide.

10. The method of claim 1,

wherein the catalytic metal layer is ultrasonicated for a time period ranging from 5 to 40 minutes.

11. The method of claim 1,

wherein the catalytic metal layer is ultrasonicated for a time period ranging from 7 to 15 minutes.

12. The method of claim 1,

wherein the catalytic metal layer is ultrasonicated for a time period ranging from 9 to 11 minutes.

13. The method of claim 1, further comprising:

a resist pattern forming step comprising;

depositing a layer of a resist material on one or more of the substrate, non-catalytic metal layer, and catalytic metal layer;

patterning the resist layer; and

according to the pattern, removing a portion of the resist layer from the underlying substrate, non-catalytic metal layer, or catalytic metal layer;

wherein the resist pattern forming step occurs before the ultrasonication and exposure to water step.

14. A method for fabricating a plurality of carbon nanotube structures having enhanced length, the method comprising:

providing a substrate;

forming a non-catalytic metal layer on the substrate;

performing a catalytic metal layer pad forming step comprising;

depositing a layer of a resist material on the non-catalytic metal layer;

patterning the resist layer;

according to the pattern, removing a portion of the resist layer from the underlying catalytic metal layer so as to expose a portion of the non-catalytic metal layer; and

forming a catalytic metal layer on the exposed portion of the non-catalytic metal layer;

removing the resistant material remaining after the catalytic metal layer pad forming step; and

subjecting the catalytic metal layer to an ultrasonication and exposure to water step, the ultrasonication and exposure to water step comprising;

submerging the catalytic metal layer in a liquid bath;

ultrasonicating the catalytic metal layer and the liquid bath; and

exposing the catalytic metal layer to water;

wherein the ultrasonication and exposure to water step occurs after the catalytic metal layer pad forming step.

15. The method of claim 14, further comprising:

wherein the ultrasonication and exposure to water step occurs after the remaining resistant material is removed.

16. The method of claim 14, further comprising:

wherein the ultrasonication and exposure to water step occurs before the remaining resistant material is removed.

17. A method for fabricating a plurality of carbon nanotube structures having enhanced length, the method comprising:

providing a substrate;

performing a catalytic metal layer pad forming step comprising;

depositing a layer of a resist material on the substrate;

patterning the resist layer; and

according to the pattern, removing a portion of the resist layer from the underlying substrate so as to expose a portion of the substrate;

forming a non-catalytic metal layer on the exposed portion of the substrate; and

forming a catalytic metal layer on the non-catalytic metal layer;

removing the resistant material remaining after the catalytic metal layer pad forming step; and

subjecting the catalytic metal layer to an ultrasonication and exposure to water step, the ultrasonication and exposure to water step comprising;

submerging the catalytic metal layer in a liquid bath;

ultrasonicating the catalytic metal layer and the liquid bath; and

exposing the catalytic metal layer to water;

wherein the ultrasonication and exposure to water step occurs after the catalytic metal layer pad forming step.

18. The method of claim 17, further comprising:

wherein the ultrasonication and exposure to water step occurs after the remaining resistant material is removed.

19. The method of claim 17, further comprising:

wherein the ultrasonication and exposure to water step occurs before the remaining resistant material is removed.