Carbon nanotube device

• US 9,406,888 B2
• Filed: 08/07/2013
• Issued: 08/02/2016
• Est. Priority Date: 08/07/2013
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: GlobalFoundries, Inc.
• Inventors: Clevenger, Lawrence A., Narayan, Chandrasekhar, Northrop, Gregory Allen, Radens, Carl John, Sapp, Brian Christopher
• Primary Examiner(s): GREEN, TELLY D
• Application Number:
  US13/960,877
• Publication Number:
  US 20150041763A1
• Time in Patent Office: 1,091 Days
• Field of Search: 257/E23.039, 257/E27.084, 257/E27.092, 257/E51.04, 257/296, 257/300, 257/301, 257/68, 257/71, 438/243, 438/386, 438/775
• US Class Current: 1/1
• 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 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: H01L 29/0673 oriented parallel to a substrate
• CPC Class Codes: H01L 29/66439 with a one- or zero-dimensional channel, e.g. quantum wire FET, in-plane gate transistor [IPG], single electron transistor [SET], striped channel transistor, Coulomb blockade transistor with an active layer made of a group 13/15 material H01L29/66469
• CPC Class Codes: H01L 29/775 with one dimensional charge carrier gas channel, e.g. quantum wire FET
• CPC Class Codes: H10K 10/464 Lateral top-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
• CPC Class Codes: Y10S 977/742 Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/842 for carbon nanotubes or fullerenes

Abstract

Embodiments of the present invention provide a method of forming carbon nanotube based semiconductor devices. The method includes creating a guiding structure in a substrate for forming a device; dispersing a plurality of carbon nanotubes inside the guiding structure, the plurality of carbon nanotubes having an orientation determined by the guiding structure; fixating the plurality of carbon nanotubes to the guiding structure; and forming one or more contacts to the device. Structure of the formed carbon nanotube device is also provided.

Claims

1. A method comprising:

creating a guiding structure in a substrate for forming a device;

dispersing a plurality of carbon nanotubes inside said guiding structure, said plurality of carbon nanotubes having an orientation determined by said guiding structure and being substantially in parallel to a top surface of said substrate;

fixating said plurality of carbon nanotubes to said guiding structure, wherein said fixating includes subjecting said plurality of carbon nanotubes to a thermal annealing process causing said plurality of carbon nanotubes to become flexible and substantially line bottom and sidewall surfaces of said guiding structure; and

forming one or more contacts to said device.

2. The method of claim 1, wherein fixating said plurality of carbon nanotubes to said guiding structure comprises depositing a dielectric layer inside said guiding structure, said dielectric layer being directly on top of said plurality of carbon nanotubes and holding said plurality of carbon nanotubes in place against said guiding structure.

3. The method of claim 2, wherein dispersing said plurality of carbon nanotubes comprises placing at least one layer of said carbon nanotubes at a bottom surface of said guiding structure, said one layer of said carbon nanotubes covers a substantial portion of said bottom surface.

4. The method of claim 3, wherein forming said one or more contacts comprises forming said one or more contacts inside said dielectric layer wherein at least one of said one or more contacts is in contact with said one layer of said carbon nanotubes.

5. The method of claim 1, wherein forming said one or more contacts comprises forming at least one of said one or more contacts to be substantially close to but not in contact with said plurality of carbon nanotubes.

6. The method of claim 1, wherein said guiding structure is a shallow trench of a rectangular shape, having a long side A and a short side B, formed inside said substrate, wherein said long side A is at least 4 times longer than that of said short side B.

7. The method of claim 6, wherein said orientation follows a direction of said long side A of said rectangular shape of said shallow trench.

14. The method of claim 1, wherein said dispersing of said plurality of carbon nanotubes includes dispersing each carbon nanotube in said plurality of carbon nanotubes parallel to another carbon nanotube in said plurality of carbon nanotubes.

16. The method of claim 1, wherein said thermal annealing process is performed at a temperature of about 300°

C. to about 950°

C. for a duration of approximately 5 minutes to approximately 300 minutes.

17. The method of claim 16, wherein said thermal annealing process increases a density of said plurality of carbon nanotubes.

8. A method of forming carbon nanotube devices, the method comprising:

creating multiple guiding structures in a substrate;

dispersing a plurality of carbon nanotubes inside said multiple guiding structures, said plurality of carbon nanotubes aligning in an orientation determined by said multiple guiding structures and being horizontal to said substrate;

fixating said plurality of carbon nanotubes to said multiple guiding structures, wherein said fixating includes subjecting said plurality of carbon nanotubes to a thermal annealing process causing said plurality of carbon nanotubes to become flexible and substantially line bottom and sidewall surfaces of said guiding structure; and

forming one or more contacts accessing said plurality of carbon nanotubes.

9. The method of claim 8, wherein said multiple guiding structures have a substantially similar shape of a rectangular having a long side A and a short side B and are aligned along a direction of said long side A.

10. The method of claim 9, wherein said orientation of said plurality of carbon nanotubes is same as said direction of said multiple guiding structures.

11. The method of claim 8, wherein fixating said plurality of carbon nanotubes to said multiple guiding structures comprises depositing a dielectric layer inside said multiple guiding structures after said thermal annealing process, said dielectric layer being directly on top of said plurality of carbon nanotubes and holding said plurality of carbon nanotubes in place against said multiple guiding structures.

12. The method of claim 8, wherein forming said one or more contacts comprises forming said one or more contacts through said dielectric layer wherein at least one of said one or more contacts is in contact with said plurality of carbon nanotubes.

13. The method of claim 8, wherein forming said one or more contacts comprises forming said one or more contacts inside said dielectric layer wherein at least one of said one or more contacts is substantially close to but not in contact with said plurality of carbon nanotubes.

15. The method of claim 8, wherein said dispersing of said plurality of carbon nanotubes includes dispersing each carbon nanotube in said plurality of carbon nanotubes parallel to another carbon nanotube in said plurality of carbon nanotubes.

18. The method of claim 8, wherein said thermal annealing process is performed at a temperature of about 300°

C. to about 950°

C. for a duration of approximately 5 minutes to approximately 300 minutes.

19. The method of claim 18, wherein said thermal annealing process increases a density of said plurality of carbon nanotubes.

20. A method comprising:

creating a guiding structure in a substrate for forming a device;

dispersing a plurality of carbon nanotubes inside said guiding structure, said plurality of carbon nanotubes having an orientation determined by said guiding structure and being substantially in parallel to a top surface of said substrate; and

fixating said plurality of carbon nanotubes to said guiding structure, wherein said fixating includes subjecting said plurality of carbon nanotubes to a thermal annealing process causing said plurality of carbon nanotubes to become flexible and substantially line bottom and sidewall surfaces of said guiding structure, and wherein said fixating also includes depositing a dielectric layer inside said guiding structure, said dielectric layer being directly on top of said plurality of carbon nanotubes and holding said plurality of carbon nanotubes in place against said guiding structure.