SURFACE NANOREPLICATION USING POLYMER NANOMASKS

• US 20140205766A1
• Filed: 01/24/2013
• Published: 07/24/2014
• Est. Priority Date: 01/24/2013
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Lyon, Jennifer Lynn, Wang, Jianguo, Yongsunthon, Ruchirej, Zhang, Ying
• Granted Patent: US 9,566,609 B2
• Time in Patent Office: Days
• US Class Current: 427/558
• CPC Class Codes: B05D 5/00 Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: G03F 7/0002 Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping

Abstract

Methods for replicating a nanopillared surface include applying a nanopillar-forming material to a surface of a replica substrate to form a precursor layer on the replica-substrate surface. A template surface of a nanomask may be contacted to the precursor layer. The nanomask may include a self-assembled polymer layer on a nanomask-substrate surface, the template surface being defined in the self-assembled polymer layer. The self-assembled polymer layer may have nano-sized pores with openings at the template surface. The precursor layer may be cured while the template surface remains in contact with the precursor layer. The nanomask is removed to expose a nanopillared surface having a plurality of nanopillars on the replica-substrate surface. The nanopillars on the replica-substrate surface may correspond to the pores in the template surface. Nanopillared surfaces may be replicated on one side of the replica substrate or on two opposing sides of the replica substrate.

Claims

1. A method for replicating a nanopillared surface, the method comprising:

applying a nanopillar-forming material to at least one replica-substrate surface of a replica substrate to form a precursor layer on the replica-substrate surface;

contacting a template surface of a nanomask to the precursor layer, the nanomask comprising a self-assembled polymer layer on a nanomask-substrate surface of a nanomask substrate, the template surface being defined in the self-assembled polymer layer opposite the nanomask-substrate surface, the self-assembled polymer layer having defined therein a plurality of pores with openings at the template surface;

curing the precursor layer while the template surface remains in contact with the precursor layer to form a cured precursor layer between the template surface and the replica-substrate surface;

removing the nanomask to expose a nanopillared surface comprising a plurality of nanopillars on the replica-substrate surface, the plurality of nanopillars on the replica-substrate surface corresponding to the plurality of pores in the template surface.

2. The method of claim 1, wherein the nanopillar-forming material is a polydimethylsiloxane combined with a curing agent.

3. The method of claim 1, wherein the nanopillar-forming material is perfluoroethertetraacrylate combined with a photoinitiator.

4. The method of claim 1, wherein at least one of the nanomask substrate and the replica substrate is glass.

5. The method of claim 1, wherein the replica substrate is glass and the nanopillar-forming material is a polydimethylsiloxane or perfluoroethertetraacrylate.

6. The method of claim 1, wherein curing the precursor layer comprises heating the precursor layer to a curing temperature.

7. The method of claim 1, wherein the nanopillar-forming material is a UV-curable polymer and curing the precursor layer comprises exposing the precursor layer to UV radiation.

8. The method of claim 1, wherein the plurality of pores in the template surface have a mean pore diameter from about 100 nm to about 200 nm.

9. The method of claim 1, wherein the plurality of nanopillars have nanopillar heights from about 50 nm to about 150 nm.

10. The method of claim 1, wherein the plurality of pores are formed by removing hydrophilic domains from the self-assembled polymer layer, the hydrophilic domains resulting from self-assembling a polymer mixture of PS-b-PEO block copolymer and poly(acrylic acid) on the nanomask-substrate surface, the PS-b-PEO block copolymer comprising polystyrene hydrophobic blocks having a number-average molecular weight of from about 100,000 Dalton to about 500,000 Dalton.

11. The method of claim 1, further comprising preparing the nanomask by:

applying a polymer solution to the nanomask-substrate surface of the nanomask substrate, the polymer solution containing

an amphiphilic block copolymer having hydrophobic blocks and hydrophilic blocks;

a hydrophilic homopolymer that is chemically compatible with the hydrophilic blocks of the amphiphilic block copolymer; and

an application solvent;

removing the application solvent to cause the amphiphilic block copolymer and the hydrophilic homopolymer in the polymer solution to self-assemble on the nanomask substrate surface to form the self-assembled polymer layer defining the template surface opposite the nanomask substrate surface, the self-assembled polymer layer having hydrophobic domains adjacent to the nanomask substrate surface and hydrophilic domains, the hydrophilic domains extending into the self-assembled polymer layer from the template surface; and

removing at least a portion of the hydrophilic domains to form the plurality of pores in the self-assembled polymer layer with openings at the template surface.

12. The method of claim 11, wherein the weight ratio of the amphiphilic block copolymer to the hydrophilic homopolymer in the polymer solution is from about 1:

1 to about 10;

1.

13. The method of claim 11, wherein the amphiphilic block copolymer and the hydrophilic homopolymer have polydispersity indices of from 1.00 to about 1.20.

14. The method of claim 11, wherein the amphiphilic block copolymer comprises a PS-b-PEO block copolymer having polystyrene hydrophobic blocks and polyethylene oxide hydrophilic blocks.

15. The method of claim 11, wherein the hydrophilic homopolymer comprises poly(acrylic acid).

16. The method of claim 11, wherein:

the amphiphilic block copolymer comprises a PS-b-PEO block copolymer comprising polystyrene hydrophobic blocks and polyethylene oxide hydrophilic blocks, the polystyrene hydrophobic blocks having a number-average molecular weight from about 100,000 Dalton to about 500,000 Dalton; and

the hydrophilic homopolymer comprises poly(acrylic acid).

17. The method of claim 16, wherein the application solvent comprises tetrahydrofuran.

18. A method for replicating nanopillared surfaces onto opposing surfaces of a replica substrate, the method comprising:

applying a first nanopillar-forming material to a first replica-substrate surface of the replica substrate to form a first precursor layer on the first replica-substrate surface;

contacting a first template surface of a first nanomask to the first precursor layer, the first nanomask comprising a first self-assembled polymer layer on a first nanomask-substrate surface of a first nanomask substrate, the first template surface being defined in the first self-assembled polymer layer opposite the first nanomask-substrate surface, the first self-assembled polymer layer having defined therein a plurality of pores with openings at the first template surface;

applying a second nanopillar-forming material to a second replica-substrate surface of the replica substrate opposite the first replica-substrate surface to form a second precursor layer on the second replica-substrate surface;

contacting a second template surface of a second nanomask to the second precursor layer, the second nanomask comprising a second self-assembled polymer layer on a second nanomask-substrate surface of a second nanomask substrate, the second template surface being defined in the second self-assembled polymer layer opposite the second nanomask-substrate surface, the second self-assembled polymer layer having defined therein a plurality of pores with openings at the second template surface;

curing the first precursor layer while the first template surface remains in contact with the first precursor layer to form a first cured precursor layer between the first template surface and the first replica-substrate surface;

curing the second precursor layer while the second template surface remains in contact with the second precursor layer to form a second cured precursor layer between the second template surface and the second replica-substrate surface;

removing the first nanomask to expose a first nanopillared surface comprising a plurality of nanopillars on the first replica-substrate surface, the plurality of nanopillars on the first replica-substrate surface corresponding to the plurality of pores in the first template surface; and

removing the second nanomask to expose a second nanopillared surface comprising a plurality of nanopillars on the second replica-substrate surface, the plurality of nanopillars on the second replica-substrate surface corresponding to the plurality of pores in the second template surface.

19. The method of claim 18, wherein the first precursor layer and the second precursor layer are cured simultaneously.

20. The method of claim 18, wherein the first precursor layer is cured before the second nanopillar-forming material is applied to the second replica-substrate surface.