Interconnected networks of single-walled carbon nanotubes

• US 6,918,284 B2
• Filed: 09/08/2003
• Issued: 07/19/2005
• Est. Priority Date: 03/24/2003
• Status: Expired due to Fees

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Campbell, Paul M., Novak, Jamie P., Snow, Eric S.
• Primary Examiner(s): PERT, EVAN T
• Application Number:
  US10/657,776
• Publication Number:
  US 20040192072A1
• Time in Patent Office: 680 Days
• Field of Search: 438/48, 438/49, 438/800, 73/310.5, 73/310.6, 324/71.1, 977/DIG.1, 257/213, 257/288, 257/414, 257/798
• US Class Current: 73/31.05
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: G01N 27/127 comprising nanoparticles
• CPC Class Codes: G01N 27/4146 involving nanosized elements, e.g. nanotubes, nanowires
• CPC Class Codes: H10K 10/466 Lateral bottom-gate IGFETs comprising only a single gate
• CPC Class Codes: H10K 85/221 Carbon nanotubes
• CPC Class Codes: Y10S 977/75 Single-walled
• CPC Class Codes: Y10S 977/842 for carbon nanotubes or fullerenes

Abstract

An electronic device having an interconnected network of carbon nanotubes on the surface of a substrate, and two or more electrical leads. The network forms an electrical connection between the leads.

Claims

1. An electronic device comprising:

a substrate;

an interconnected network of carbon nanotubes on the surface of the substrate; and

two or more electrical leads on the surface of the substrate;

wherein the network forms an electrical connection between the leads; and

wherein substantially none of the carbon nanotubes is in contact with both of the leads.

2. The device of claim 1, wherein the carbon nanotubes are single-walled carbon nanotubes.

3. The device of claim 1, wherein the network is a sub-monolayer of carbon nanotubes.

4. The device of claim 1, wherein the network is up to about 100 nm thick.

5. The device of claim 1, wherein the density of carbon nanotubes is at most about one thousand times the reciprocal of the square of the average length of the carbon nanotubes.

6. The device of claim 1,

wherein the network comprises metallic single-walled carbon nanotubes;

and

wherein the density of the metallic single-walled carbon nanotubes is at most about the reciprocal of the square of the average length of the carbon nanotubes.

7. The device of claim 1, wherein the density of carbon nanotubes is at most about 10 μ

m<sup>−

2</sup>.

8. The device of claim 1, wherein the density of the carbon nanotubes is at least about one tenth the reciprocal of the square of the average length of the carbon nanotubes.

9. The device of claim 1, wherein the density of the carbon nanotubes is at least about 0.3 μ

m<sup>−

2</sup>.

10. The device of claim 1, wherein at least about 75% of the carbon nanotubes are at least partially in contact with the substrate.

11. The device of claim 1, wherein the network is semiconducting.

12. The device of claim 1, wherein the network further comprises a filler material.

13. The device of claim 12, wherein one or more electrical properties of the filler material are altered by the network.

14. The device of claim 12, wherein the filler material is a polymer.

15. The device of claim 1, wherein the distance between the leads is greater then the average length of the carbon nanotubes.

16. The device of claim 1, wherein the substrate is flexible.

17. The device of claim 1, further comprising a gate lead;

wherein the device is a field effect transistor;

wherein the leads electrically connected to the network form a source and a drain of the transistor; and

wherein the network forms a conduction channel of the transistor.

18. The device of claim 17, further comprising an insulating material between the network and the gate.

19. The device of claim 17, wherein the gate is part of the substrate.

20. The device of claim 17, wherein the transistor has an on-to-off ratio of at least about 10⁵.

21. The device of claim 17, wherein the substrate is flexible.

22. The device of claim 17, wherein the conductivity of the network is modulated by a voltage applied to the gate.

23. The device of claim 1,

wherein the network can be exposed to a gaseous sample;

and

wherein the resistivity of the network changes in response to the presence of one or more analytes in the sample.

24. The device of claim 23, wherein the substrate is flexible.

25. The device of claim 23, wherein substrate is a tube and the network is on the inside surface of the tube.

26. The device of claim 25, wherein the tube comprises quartz.

27. The device of claim 23, wherein the electrical leads comprise silver.

28. A display device comprising the device of claim 1.

29. The device of claim 1, wherein the substrate is substantially free of catalyst.

30. The device of claim 1, wherein at least one of the carbon nanotubes is in contact with neither of the leads.

31. The device of claim 1, wherein none of the nanotubes is in contact with both of the leads.

32. An electronic device comprising:

a substrate;

an interconnected network of nanofilaments on the surface of the substrate;

two or more electrical leads on the surface of the substrate;

wherein the network forms an electrical connection between the leads; and

wherein substantially none of the nanofilaments is in contact with both of the leads.

33. The device of claim 32, wherein none of the nanofilaments is in contact with both of the leads.

34. The device of claim 32, wherein at least one of the nanofilaments is in contact with neither of the leads.

35. The device of claim 32, wherein the substrate is substantially free of catalyst.

36. An electronic device comprising:

a substrate;

an interconnected network of carbon nanotubes on the surface of the substrate; and

two or more electrical leads;

wherein the network forms an electrical connection between the leads;

wherein the network can be exposed to a gaseous sample;

wherein the resistivity of the network changes in response to the presence of one or more analytes in the sample; and

wherein the substrate is a tube and the network is on the inside surface of the tube.

37. The device of claim 36, wherein the tube comprises quartz.

38. A field effect transistor comprising:

a substrate;

an interconnected network of carbon nanotubes on the surface of the substrate;

a source lead;

a drain lead, and

a gate lead

wherein the network forms a conduction channel of the transistor between the source and drain; and

wherein the transistor has an on-to-off ratio of at least about 10⁵.