Nanostructured graphene with atomically-smooth edges

Patent metadata

Field	Value
Publication number	US-9394177-B2
Application number	US-201113282666-A
Country	US
Kind code	B2
Filing date	Oct 27, 2011
Priority date	Oct 27, 2011
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

Methods of producing layers of patterned graphene with smooth edges are provided. The methods comprise the steps of fabricating a layer of crystalline graphene on a surface, wherein the layer of crystalline graphene has a crystallographically disordered edge, and decreasing the crystallographic disorder of the edge of the layer of crystalline graphene by heating the layer of crystalline graphene on the surface at an elevated temperature in a catalytic environment comprising carbon-containing molecules.

First claim

What is claimed is:

1. A method for fabricating graphene structures, the method comprising:
(a) growing a layer of crystalline graphene on a surface via vapor deposition, wherein the layer of crystalline graphene is grown with one or more crystallographically disordered edges;
(b) discontinuing the vapor deposition growth of the layer of crystalline graphene with one or more crystallographically disordered edges; and
(c) subsequently decreasing the crystallographic disorder of the one or more crystallographically disordered edges by heating the layer of crystalline graphene on the surface at an elevated temperature in a catalytic environment comprising carbon-containing molecules, wherein the decrease in crystallographic disorder is catalyzed by the surface and occurs without the continued vapor deposition growth of the layer of crystalline graphene.

2. The method of claim 1 , wherein heating the layer of crystalline graphene comprises heating the crystalline graphene to a temperature of no greater than about 1000° C.

3. The method of claim 1 , wherein heating the layer of crystalline graphene comprises heating the crystalline graphene to a temperature in the range from about 700° C. to about 900° C.

4. The method of claim 3 , wherein the catalytic environment further comprises hydrogen gas.

5. The method of claim 1 , wherein the carbon-containing molecules are in the vapor phase.

6. The method of claim 5 , wherein the carbon-containing molecules comprise aliphatic hydrocarbons, aromatic hydrocarbons or derivatives thereof.

7. The method of claim 1 , wherein the amount of carbon-containing molecules present during the step of decreasing the crystallographic disorder of the one or more crystallographically disordered edges by heating the layer of crystalline graphene on the surface at an elevated temperature in a catalytic environment comprising carbon-containing molecules is sufficient to suppress carbon sublimation from the surface.

8. The method of claim 1 , wherein decreasing the crystallographic disorder of the one or more crystallographically disordered edges makes the area of the layer of crystalline graphene smaller.

9. The method of claim 1 , wherein the step of heating the layer of crystalline graphene on the surface at an elevated temperature in a catalytic environment comprising carbon-containing molecules is carried out at a lower temperature than the vapor deposition growth.

10. The method of claim 1 , wherein the catalytic environment further comprises hydrogen gas.

11. A method for fabricating graphene structures in a pre-formed layer of crystalline graphene on a metal surface, the method comprising:
(a) patterning features having one or more crystallographically disordered edges into the pre-formed layer of crystalline graphene via top-down lithographic patterning; and
(b) subsequently decreasing the crystallographic disorder of the one or more crystallographically disordered edges by heating the layer of crystalline graphene on the metal surface at an elevated temperature in a catalytic environment comprising carbon-containing molecules, wherein the decrease in crystallographic disorder is catalyzed by the metal surface and occurs without vapor deposition growth of the layer of crystalline graphene.

12. The method of claim 11 , wherein the metal comprises Cu.

13. The method of claim 11 , wherein the layer of graphene is lithographically patterned into an antidot lattice comprising holes having irregularly shaped edges and further wherein the step of decreasing the crystallographic disorder of the one or more crystallographically disordered edges comprises converting the holes into hexagonally-shaped holes and improving the alignment between the holes and the hexagonal symmetry of the graphene lattice.

14. The method of claim 11 , wherein the layer of graphene is lithographically patterned into an array of nanoribbons having irregularly shaped edges and further wherein the step of decreasing the crystallographic disorder of the one or more crystallographically disordered edges comprises improving the alignment between the edges of the nanoribbons and the hexagonal symmetry of the graphene lattice.

15. The method of claim 11 , further comprising growing a layer of crystalline graphene on a surface via chemical vapor deposition to provide the pre-formed layer of crystalline graphene into which the features having one or more crystallographically disordered edges are subsequently patterned via top-down lithographic patterning.

16. The method of claim 15 , wherein the step of by heating the layer of crystalline graphene on the surface at an elevated temperature in a catalytic environment comprising carbon-containing molecules is carried out at a lower temperature than the chemical vapor deposition growth.

17. The method of claim 11 , wherein decreasing the crystallographic disorder of the one or more crystallographically disordered edges makes the area of the layer of crystalline graphene smaller.

18. The method of claim 11 , wherein heating the layer of crystalline graphene comprises heating the crystalline graphene to a temperature in the range from about 700° C. to about 1000° C.

19. The method of claim 18 , wherein the catalytic environment further comprises hydrogen gas.

20. The method of claim 11 , wherein the catalytic environment further comprises hydrogen gas.

Assignees

• Arnold Michael S
• Gopalan Padma
• Safron Nathaniel S
• Kim Myungwoong
• Wisconsin Alumni Res Found

Inventors

• Arnold Michael S
• Gopalan Padma
• Safron Nathaniel S
• Kim Myungwoong

Classifications

• Y10T428/24802

  Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.] · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• C01B31/0438 Primary

  Chemistry & Metallurgy · mapped topic

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• C01B31/0484

  Chemistry & Metallurgy · mapped topic