Method of forming oriented block copolymer line patterns, block copolymer line patterns formed thereby, and their use to form patterned articles

1. A method of preparing a block copolymer film comprising a line pattern, comprising:

forming a block copolymer film on a substrate surface comprising parallel facets; and

annealing the block copolymer film to form an annealed block copolymer film comprising linear microdomains parallel to the substrate surface and orthogonal to the parallel facets;

wherein the parallel facets of the substrate are characterized by a pitch, λ, having units of nanometers;

wherein the block copolymer in bulk comprises a hexagonal array of cylindrical microdomains characterized by a center-to-center spacing, L 2 , of adjacent cylindrical microdomains, wherein L 2 has units of nanometers; and

wherein λ/L 2 is either less than or equal to 0.73 or greater than or equal to 1.4.

2. The method of claim 1 , wherein the linear microdomains have a periodicity of about 15 to about 60 nanometers.

3. The method of claim 1 , wherein the annealed block copolymer film has an order parameter, f, of at least 0.95 over an area of at least 0.5 millimeter 2 .

4. The method of claim 1 , wherein the annealed block copolymer film has an order parameter, f, over an area of at least 0.5 millimeter 2 that is greater than the corresponding order parameter for the substrate surface.

5. The method of claim 1 , wherein the block copolymer film has a thickness of about L 1 to about 2L 1 , wherein L 1 is a center-to-center domain spacing of cylindrical microdomains in bulk block copolymer, and wherein L 1 has units of nanometers.

6. The method of claim 1 , wherein the block copolymer comprises about 65 to about 80 volume percent of a major block and about 20 to about 35 volume percent of a minor block.

7. The method of claim 1 , wherein the block copolymer film comprises a block copolymer selected from the group consisting of polystyrene-b-poly(ethylene oxide), polystyrene-b-poly(2-vinylpyridine), polystyrene-b-poly(4-vinylpyridine), polystyrene-b-polybutadiene, polystyrene-b-polydimethylsiloxane, polystyrene-b-polylactide, and polystyrene-b-poly(methyl methacrylate).

8. The method of claim 1 , wherein the block copolymer film comprises a polystyrene-b-poly(ethylene oxide).

9. The method of claim 1 , wherein the substrate consists essentially of a single crystal.

10. The method of claim 1 , wherein the substrate is selected from the group consisting of crystalline silicon, doped crystalline silicon, and crystalline aluminum oxide.

11. The method of claim 1 , wherein the substrate comprises a polymeric replica of a crystalline surface comprising parallel facets.

12. The method of claim 11 , wherein the polymeric replica comprises a polymer selected from the group consisting of poly(ethylene terephthalate)s, poly(butylene terephthalate)s, polydimethylsiloxanes, polytetrafluoroethylenes, random copolymers of tetrafluoroethylene and hexafluoropropylene, and polyimides derived from pyromellitic dianhydride and 4,4′-oxydianiline.

13. The method of claim 1 , wherein said annealing the block copolymer film comprises thermal annealing.

14. The method of claim 1 , wherein said annealing the block copolymer film comprises solvent vapor annealing.

15. The method of claim 14 , wherein the block copolymer comprises about 65 to about 80 volume percent of a major block and about 20 to about 35 volume percent of a minor block, and wherein said solvent vapor annealing comprises exposing the block copolymer film to a vapor of a solvent in which the minor block is more soluble than the major block.

16. The method of claim 14 , wherein the block copolymer comprises a polystyrene-b-poly(ethylene oxide), and wherein said solvent vapor annealing comprises exposing the block copolymer film to a solvent vapor comprising water and tetrahydrofuran.

17. The method of claim 14 , wherein the block copolymer comprises a polystyrene-b-poly(ethylene oxide), and wherein said solvent vapor annealing comprises exposing the block copolymer film to a first solvent vapor comprising water, then exposing the block copolymer film to a second solvent vapor comprising water and tetrahydrofuran.

18. The method of claim 14 , wherein said solvent vapor annealing comprises exposing the block copolymer film to a solvent vapor for about 1 to about 4 hours at a temperature of about 15 to about 30° C.

19. The method of claim 1 , wherein said annealing the block copolymer film comprises thermal annealing and solvent vapor annealing.

20. The method of claim 1 , wherein λ/L 2 is less than or equal to 0.73.

21. The method of claim 1 , wherein λ/L 2 is greater than or equal to 1.4.

22. The method of claim 1 , wherein said annealing the block copolymer film comprises annealing the block copolymer film to form a first annealed block copolymer film comprising a hexagonal array of cylindrical microdomains having a major axis normal to the film, and further annealing the first annealed block copolymer film to form the annealed block copolymer film comprising linear microdomains parallel to the substrate surface and orthogonal to the parallel facets.

23. The method of claim 1 ,

wherein the block copolymer film has a thickness of about L 1 to about 2L 1 , wherein L 1 is a center-to-center domain spacing of cylindrical microdomains in bulk block copolymer, and wherein L 1 has units of nanometers;

wherein the block copolymer film comprises a polystyrene-b-poly(ethylene oxide);

wherein the polystyrene-b-poly(ethylene oxide) comprises about 65 to about 80 volume percent of a polystyrene block and about 20 to about 35 volume percent of a poly(ethylene oxide) block;

wherein the substrate comprises crystalline aluminum oxide or a poly(butylene terephthalate) replica of a crystalline aluminum oxide surface;

wherein said annealing comprises exposing the block copolymer film to a solvent vapor comprising water and tetrahydrofuran for about 1 to about 4 hours at a temperature of about 15 to about 30° C.; and

wherein the annealed block copolymer film has an order parameter, f, of at least 0.95 over an area of at least 0.5 millimeter.