Carbon nanotube devices

• US 20020179434A1
• Filed: 06/18/2002
• Published: 12/05/2002
• Est. Priority Date: 08/14/1998
• Status: Active Grant

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford University)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford University)
• Inventors: Kong, Jing, Dai, Hongjie
• Granted Patent: US 7,416,699 B2
• Time in Patent Office: Days
• US Class Current: 204/242
• CPC Class Codes: B82B 1/00 Nanostructures formed by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
• CPC Class Codes: B82B 3/00 Manufacture or treatment of nanostructures by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
• 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 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• 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 32/162 characterised by catalysts
• CPC Class Codes: G01N 27/127 comprising nanoparticles
• CPC Class Codes: Y10S 977/70 Nanostructure
• CPC Class Codes: Y10S 977/742 Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/745 having a modified surface
• CPC Class Codes: Y10S 977/746 Modified with biological, organic, or hydrocarbon material
• CPC Class Codes: Y10S 977/75 Single-walled
• CPC Class Codes: Y10S 977/752 Multi-walled
• CPC Class Codes: Y10T 436/11 Automated chemical analysis
• CPC Class Codes: Y10T 436/23 Carbon containing

Abstract

Nanotubes and nanotube-based devices are implemented in a variety of applications. According to an example embodiment of the present invention, a nanotube is adapted to pass current between two conductive elements. In one implementation, each conductive element includes a catalyst material, wherein electrical connection is made to opposite ends of the nanotube at each of the catalyst portions. In one implementation, the electrical connection is used to detect an electrical characteristic of the nanotube, such as the response of the nanotube to exposure to one or more of a variety of materials. In another implementation, the nanotube is used for chemical and biological sensing. In still another implementation, a particular functionality is imparted to the nanotube using one or more of a variety of materials coupled to the nanotube, such as metal particles, biological particles and/or layers of the same.

Claims

1. A nanotube device comprising:

first and second conducting elements and at least one nanotube adapted to pass current between the first and second conducting elements, wherein a first end of said at least one nanotube is in electrical contact with the first conducting element and a second end of said at least one nanotube is in electrical contact with the second conducting element.

2. The nanotube device of claim 1, wherein said nanotube is a carbon nanotube.

3. The nanotube device of claim 2, wherein said nanotube is a single-walled nanotube.

4. The nanotube device of claim 1, wherein said nanotube includes silicon.

5. The nanotube device of claim 1, wherein said nanotube is semiconducting between said first and second conducting elements.

6. The nanotube device of claim 1, wherein said nanotube includes metal.

7. The nanotube device of claim 1, wherein said nanotube is disposed on a surface.

8. The nanotube device of claim 7, wherein said surface is a top surface of a substrate comprising a material selected from a group consisting of silicon, alumina, quartz, silica and silicon nitride.

9. The nanotube device of claim 8, wherein said substrate comprises doped silicon covered with a layer of native oxide.

10. The nanotube device of claim 7, further comprising a gate in the surface and configured and arranged to apply a gating voltage to the nanotube.

11. The nanotube device of claim 1, wherein at least one of said first and second conducting elements comprises a catalyst island covered by a metal electrode, and wherein at least one of said ends of said nanotube is rooted in said catalyst island and covered by said metal electrode.

12. The nanotube device of claim 11, wherein said catalyst island comprises a material selected from a group consisting of iron, molybdenum, cobalt, nickel, ruthenium, zinc and oxides thereof.

13. The nanotube device of claim 11, wherein said catalyst island comprises Fe₂O₃ and alumina nanoparticles.

14. The nanotube device of claim 11, wherein said catalyst island is between about 3-5 microns wide.

15. The nanotube device of claim 11, wherein said metal electrode comprises an alloy of nickel-gold.

16. The nanotube device of claim 11, wherein said metal electrode comprises an alloy of titanium-gold.

17. The nanotube device of claim 1, wherein at least one of said conducting elements comprises a metal pad covering at least one of said ends of said nanotube.

18. The nanotube device of claim 17, wherein said metal pad comprises a material selected from the group consisting of titanium, gold, aluminum, chromium, and platinum.

19. The nanotube device of claim 1, further comprising one or more sensing agents attached to said nanotube.

20. The nanotube device of claim 19, wherein, upon exposure to a selected molecule, the nanotube exhibits an electrical response that is a function of the one or more sensing agents.

21. The nanotube device of claim 19, wherein the one or more sensing agents includes metal.

22. The nanotube device of claim 19, wherein the electrical conductance of the nanotube is a function of the one or more sensing agents.

23. The nanotube device of claim 1, wherein the at least one nanotube extends from a catalyst material.

24. The nanotube device of claim 23, wherein the catalyst material is disposed on a substrate.

25. The nanotube device of claim 23, wherein the catalyst material is the first conducting element.

26. The nanotube device of claim 23, wherein the catalyst material is the second conducting element.

27. The nanotube device of claim 1, further comprising a gate disposed adjacent to the nanotube and adapted to apply a gating voltage to the nanotube.

28. The nanotube device of claim 1, wherein the gate is further adapted to apply a gating voltage that alters an electrical characteristic of the nanotube.

30. The nanotube apparatus of claim 29, wherein said nanotube film comprises interconnected carbon nanotubes.

31. The nanotube apparatus of claim 30, wherein said nanotube film comprises interconnected single-walled nanotubes.

32. The nanotube apparatus of claim 29, wherein said nanotube film comprises interconnected silicon nanotubes.

33. The nanotube apparatus of claim 29, wherein said nanotube film comprises semiconducting nanotubes.

34. The nanotube apparatus of claim 29, wherein said nanotube film comprises metallic nanotubes.

35. The nanotube apparatus of claim 29, wherein said nanotube film is disposed on a top surface of a substrate.

36. The nanotube apparatus of claim 35, wherein said substrate comprises a material selected from a group consisting of silicon, alumina, quartz, silica and silicon nitride.

37. The nanotube apparatus of claim 36, wherein said substrate further comprises a catalyst layer on its top surface.

38. The nanotube apparatus of claim 37, wherein said catalyst layer comprises a material selected from a group consisting of iron, molybdenum, cobalt, nickel, ruthenium, zinc and oxides thereof.

39. The nanotube apparatus of claim 37, wherein said catalyst layer comprises Fe₂O₃ and alumina nanoparticles.

40. The nanotube apparatus of claim 29, wherein at least one of said electrodes comprises an alloy of nickel-gold.

41. The nanotube apparatus of claim 29, wherein at least one of said electrodes comprises an alloy of titanium-gold.

42. The nanotube apparatus of claim 29, wherein said electrodes are disposed between about 1-100 microns apart.

43. The nanotube apparatus of claim 29, further comprising one or more sensing agents attached to said nanotube film and wherein said nanotube film is adapted to exhibit an electrical characteristic that is a function of the one or more sensing agents.

44. The nanotube apparatus of claim 29, further comprising a gate adapted to apply a gating voltage to the nanotube film.

46. The nanotube device of claim 45, wherein said at least one sensing agent comprises at least one material selected from the group consisting of:

metal particles, polymers, biological species, gold, platinum, nickel, rhodium, palladium, TiO₂, thiol, and enzymes.

47. The nanotube device of claim 45, wherein said at least one carbon nanotube is semiconducting.

48. The nanotube device of claim 45, further comprising a voltage source adapted to apply a gating voltage to bias said at least one carbon nanotube to respond to a particular molecular species.

49. The nanotube device of claim 48, wherein said voltage source is configured and arranged to apply a gating voltage between about −

20 and 20 Volts to the at least one carbon nanotube.

29. A nanotube device comprising:

a nanotube film comprising a plurality of nanotubes and having a first end and a second end; and

first and second electrodes respectively disposed on said first end and said second end of said nanotube film, wherein the nanotube film is adapted to pass current between the first and second electrodes.

45. A nanotube device comprising:

first and second conducting elements;

at least one carbon nanotube having first and second ends in electrical contact, respectively, with the first and second conducting elements;

a coating of at least one sensing agent deposited on said carbon nanotube; and

wherein the coated carbon nanotube responds to a particular molecular species.