Methods of Making Spatially Aligned Nanotubes and Nanotube Arrays

• US 20120321785A1
• Filed: 08/28/2012
• Published: 12/20/2012
• Est. Priority Date: 03/03/2006
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Rogers, John A., Park, Jang-Ung, Kocabas, Coskun, Shim, Moonsub, Kang, Seong Jun
• Granted Patent: US 8,367,035 B2
• Time in Patent Office: Days
• US Class Current: 427/249.1
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• 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 2202/02 Single-walled nanotubes
• CPC Class Codes: C01B 2202/08 Aligned nanotubes
• CPC Class Codes: C01B 2202/34 Length
• CPC Class Codes: C01B 32/162 characterised by catalysts
• CPC Class Codes: H10K 10/464 Lateral top-gate IGFETs comprising only a single gate
• CPC Class Codes: H10K 10/466 Lateral bottom-gate IGFETs comprising only a single gate
• CPC Class Codes: H10K 71/191 characterised by provisions for the orientation or alignment of the layer to be deposited
• CPC Class Codes: H10K 85/221 Carbon nanotubes

Abstract

The present invention provides arrays of longitudinally aligned carbon nanotubes having specified positions, nanotube densities and orientations, and corresponding methods of making nanotube arrays using guided growth and guided deposition methods. Also provided are electronic devices and device arrays comprising one or more arrays of longitudinally aligned carbon nanotubes including multilayer nanotube array structures and devices.

Claims

1. A method for making an array of longitudinally aligned carbon nanotubes;

said method comprising the steps of;

providing a guided growth substrate having a receiving surface;

patterning said receiving surface with carbon nanotube growth catalyst, thereby generating a two dimensional pattern of catalyst-containing regions of said receiving surface and regions of said receiving surface having substantially no catalyst present; and

growing nanotubes on said guided growth substrate via guided growth, wherein at least a portion of said nanotubes grow along nanotube growth axes parallel to at least one principle guided growth axis of said guided growth substrate, and wherein at least a portion of said nanotubes grow from said catalyst-containing regions to said regions of said receiving surface having substantially no catalyst present, thereby making said array of longitudinally aligned carbon nanotubes.

2. The method of claim 1 wherein said step of growing nanotubes on said substrate is carried out by exposure of said carbon nanotube growth catalyst patterned on said receiving surface to a precursor gas.

3. The method of claim 1 wherein said step of growing nanotubes on said substrate is carried out by chemical vapor deposition.

4. The method of claim 1 wherein said step of growing nanotubes on said substrate generates single walled carbon nanotubes.

5. The method of claim 1 wherein said guided growth substrate is single crystalline sapphire or single crystalline quartz.

6. The method of claim 1 wherein said guided growth substrate is a Y-cut quartz substrate.

7. The method of claim 6 wherein said Y-cut quartz substrate has a cut angle selected over the range of about 0 degrees to about 42.75 degrees.

8. The method of claim 1 wherein said guided growth substrate is an AT cut quartz substrate or an ST cut quartz substrate.

9. The method of claim 1 wherein said catalyst-containing regions have a surface concentration of catalyst selected from the range of about 1000 particles μ

m<sup>−

2</sup> to about 10 particles μ

m<sup>−

2</sup>.

10. The method of claim 1 wherein said regions of said receiving surface having substantially no catalyst present have a surface concentration of catalyst less than or equal to about 1 particles μ

m<sup>−

2</sup>.

11. The method of claim 1 wherein said catalyst-containing regions are bands of catalyst that are separated from each other by said regions of said receiving surface having substantially no catalyst present.

12. The method of claim 1 wherein said bands of catalyst are longitudinal oriented along longitudinal catalyst alignment axes that are oriented perpendicular to said principle guided growth axis of said guided growth substrate.

13. The method of claim 12 wherein said bands of catalyst comprise a first band and a second band that are longitudinal oriented along parallel catalyst alignment axes, wherein at least a portion of said nanotubes grow along segments of said nanotube growth axes extending from said first band to said second band, thereby generating said array of longitudinally aligned nanotubes extending from said first band to said second band.

14. The method of claim 13 wherein the density of longitudinally aligned carbon nanotubes positioned between said first and second bands of catalyst is greater than or equal to about 5 nanotubes μ

m<sup>−

1</sup>.

15. The method of claim 1 wherein at least 95% of said longitudinally aligned carbon nanotubes of said array are parallel to each other within about 10 degrees.

16. The method of claim 1 wherein at least 95% of said longitudinally aligned carbon nanotubes of said array exhibit a high degree of linearity.

17. The method of claim 1 wherein said step of patterning said receiving surface with carbon nanotube growth catalyst comprises the steps of:

depositing catalyst onto selected deposition areas of said receiving surface, and

preventing catalyst accumulation onto said deposition areas of said receiving surface between said catalyst-containing regions, thereby generating said two dimensional pattern of catalyst-containing and regions of said receiving surface having substantially no catalyst present.

18. The method of claim 1 wherein said step of patterning said receiving surface with carbon nanotube growth catalyst comprises the steps of:

providing a catalyst layer of said nanotube growth catalyst to said receiving surface;

removing catalyst from selected areas of said catalyst layer, thereby generating said two dimensional pattern of catalyst-containing and regions of said receiving surface having substantially no catalyst present.

19. The method of claim 1 further comprising the step of annealing said guided growth substrate.

20. The method of claim 1 further comprising the step of oxidizing said carbon nanotube growth catalyst, reducing said carbon nanotube growth catalyst or both oxidizing and reducing said carbon nanotube growth catalyst.