Methods of fabrication of graphene nanoribbons
View Patent ↗Methods of fabricating graphene nanoribbons include depositing a catalyst layer on a substrate. A masking layer is deposited on the catalyst layer. The masking layer and the catalyst layer are etched to form a structure on the substrate, the structure comprising a portion of the catalyst layer and a portion of the masking layer disposed on the catalyst layer, with sidewalls of the catalyst layer being exposed. A graphene layer is formed on a sidewall of the catalyst layer with a carbon-containing gas.
1. A method comprising:
(a) depositing a catalyst layer on a substrate;
(b) depositing a masking layer on the catalyst layer;
(c) etching the masking layer and the catalyst layer to form a structure on the substrate, the structure comprising a portion of the catalyst layer and a portion of the masking layer disposed on the catalyst layer, sidewalls of the catalyst layer being exposed; and
(d) forming a graphene layer on a sidewall of the catalyst layer with a carbon-containing gas.
2. The method of claim 1 , wherein the catalyst layer is selected from a group consisting of nickel, copper, cobalt, iron, molybdenum, titanium, and tungsten.
3. The method of claim 1 , wherein the catalyst layer comprises nickel.
4. The method of claim 3 , wherein the masking layer comprises aluminum oxide.
5. The method of claim 1 , wherein the carbon-containing gas is selected from a group consisting of methane, ethane, ethylene, and acetylene.
6. The method of claim 1 , wherein operation (d) is performed at a temperature that thermally decomposes the carbon-containing gas, and wherein the temperature is about 700° C. to 1000° C.
7. The method of claim 1 , further comprising:
after operation (d), removing the portion of the masking layer and the portion of the catalyst layer.
8. The method of claim 7 , wherein after removing the portion of the masking layer and the portion of the catalyst layer, a surface of the graphene layer that was disposed on the sidewall of the catalyst layer is disposed on the substrate.
9. The method of claim 1 , wherein a thickness of the catalyst layer deposited on the substrate is about 1 nanometer to 20 nanometers.
10. The method of claim 9 , wherein a width of the graphene layer is determined in part by the thickness of the catalyst layer, and wherein the graphene layer is about 1 nanometer to 20 nanometers wide.
11. The method of claim 9 , wherein a height of the sidewalls of the catalyst layer are determined by the thickness of the catalyst layer deposited on the substrate.
12. The method of claim 1 , wherein the substrate comprises silicon.
13. The method of claim 1 , wherein the graphene layer is not formed on surfaces of the masking layer or the substrate.
14. The method of claim 1 , wherein the graphene layer is not formed on surfaces of the catalyst layer other than the sidewalls of the catalyst layer.
15. The method of claim 1 , wherein operation (d) is performed with a plasma enhanced chemical vapor deposition process.