Forming self-aligned nano-electrodes

• US 20050224778A1
• Filed: 04/07/2004
• Published: 10/13/2005
• Est. Priority Date: 04/07/2004
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Sivakumar, Swaminathan, Berlin, Andrew A., Bohr, Mark, Dubin, Valery M.
• Granted Patent: US 7,312,155 B2
• Time in Patent Office: Days
• US Class Current: 257/3
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H01L 21/76838 characterised by the formation and the after-treatment of the conductors etching for patterning the conductors H01L21/3213
• CPC Class Codes: H01L 21/76852 the layer also covering the sidewalls of the conductive structure
• CPC Class Codes: H01L 2221/1094 Conducting structures comprising nanotubes or nanowires
• CPC Class Codes: H10K 71/60 Forming conductive regions or layers, e.g. electrodes
• CPC Class Codes: H10K 85/221 Carbon nanotubes
• CPC Class Codes: H10K 85/615 Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
• CPC Class Codes: Y10S 977/742 Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/936 in a transistor or 3-terminal device

Abstract

A nano-electrode or nano-wire may be etched centrally to form a gap between nano-electrode portions. The portions may ultimately constitute a single electron transistor. The source and drain formed from the electrode portions are self-aligned with one another. Using spacer technology, the gap between the electrodes may be made very small.

Claims

1. A method comprising:

etching a gap along the length of a nano-electrode.

2. The method of claim 1 including etching a gap along the length of a carbon nanotube.

3. The method of claim 2 including etching two gaps along the length of a carbon nanotube to form the source and drain of a transistor.

4. The method of claim 1 including forming a mask over a nano-electrode, forming an aperture in said mask, and forming a spacer in said mask to narrow said aperture.

5. The method of claim 4 including using said spacer to etch said gap along the length of said nano-electrode.

6. The method of claim 5 including selectively depositing a metal in said aperture.

7. The method of claim 6 including electrolessly plating a metal in said aperture to narrow the gap between said nano-electrodes.

8. The method of claim 7 including self-terminating the narrowing of the gap.

9. The method of claim 8 including using absorbed layers of organics on the surface of the metal during plating.

10. The method of claim 1 including forming said nano-electrode of metal wire.

11. A semiconductor structure comprising:

a carbon nanotube formed over a substrate; and

a dielectric layer formed over said carbon nanotube, said dielectric layer having an aperture formed therein.

12. The structure of claim 11 wherein said dielectric layer includes a metal sidewall on each side of said aperture.

13. The structure of claim 11 including a pair of apertures spaced along the length of said carbon nanotube.

14. The structure of claim 11 including a plurality of generally parallel carbon nanotubes formed over a substrate and a single aperture through a dielectric layer over all of said carbon nanotubes.

15. A method comprising:

depositing a carbon nanotube on a semiconductor substrate;

covering said carbon nanotube with a dielectric layer;

etching an aperture through said dielectric layer centrally down to said carbon nanotube; and

etching through said carbon nanotube to form two carbon nanotube portions separated by a gap.

20. The method of claim 15 including etching through said carbon nanotube at two spaced locations to form three carbon nanotube portions separated by two gaps.

16. The method of claim 16 including narrowing said aperture before etching said carbon nanotube by applying sidewall spacers to said aperture.

17. The method of claim 16 including applying a metal layer to the exposed ends of said carbon nanotube portions.

18. The method of claim 17 including self-terminating the narrowing of said gap.

19. The method of claim 18 including applying an absorbed layer of organic material on the surface of the metal to terminate the narrowing of the gap.