Methods of fabricating large-area, semiconducting nanoperforated graphene materials
Methods for forming a nanoperforated graphene material are provided. The methods comprise forming an etch mask defining a periodic array of holes over a graphene material and patterning the periodic array of holes into the graphene material. The etch mask comprises a pattern-defining block copolymer layer, and can optionally also comprise a wetting layer and a neutral layer. The nanoperforated graphene material can consist of a single sheet of graphene or a plurality of graphene sheets.
1. An etch mask structure for a graphene material, the structure comprising an etch mask disposed over a graphene material, wherein the etch mask comprises a wetting layer in contact with the graphene material, a neutral layer comprising a copolymer disposed over the wetting layer, and a pattern-defining block copolymer layer disposed over the neutral layer, wherein the pattern-defining block copolymer is phase segregated into a pattern of domains; and further wherein the neutral layer is characterized in that is induces the formation of the pattern of domains in the pattern-defining block copolymer.
2. The structure of claim 1 , wherein the wetting layer is a layer of silicon oxide.
3. The structure of claim 2 , wherein the layer of silicon oxide has a thickness of about 5 to about 20 nm.
4. The structure of claim 2 , wherein the neutral layer comprises a copolymer polymerized from vinyl monomers and acrylate monomers.
5. The structure of claim 4 , wherein the pattern-defining block copolymer is polymerized from vinyl monomers and acrylate monomers.
6. The structure of claim 5 , wherein the pattern-defining block copolymer is P(S-b-MMA).
7. The structure of claim 2 , wherein the graphene material consists of a single layer of graphene.
8. The structure of claim 2 , wherein the graphene material comprises highly oriented pyrolytic graphite.
9. The structure of claim 1 , wherein the wetting layer comprises a self-assembled monolayer.
10. The structure of claim 9 , wherein the self-assembled monolayer comprises molecules having a first end that is sufficiently polar to undergo an attractive interaction with the copolymer of the neutral layer and a second end comprising a plurality of conjugated rings that undergo a π-π stacking interaction with the graphene material.
11. The structure of claim 10 , wherein the first end of the molecules comprise an acid group and second end of the molecules comprise at least three fused six-member aromatic rings.
12. The structure of claim 11 , wherein the molecules are pyrene butyric acid molecules.
13. The structure of claim 9 , wherein the neutral layer comprises a copolymer polymerized from vinyl monomers and acrylate monomers.
14. The structure of claim 13 , wherein the pattern-defining block copolymer is polymerized from vinyl monomers and acrylate monomers.
15. The structure of claim 14 , wherein the pattern-defining block copolymer is P(S-b-MMA).
16. The structure of claim 9 , wherein the graphene material consists of a single layer of graphene.
17. The structure of claim 9 , wherein the graphene material comprises highly oriented pyrolytic graphite.
18. The structure of claim 1 , wherein the graphene material consists of a single layer of graphene.
19. The structure of claim 1 , wherein the graphene material comprises highly oriented pyrolytic graphite.