Sub-10 nm line features via rapid graphoepitaxial self-assembly of amphiphilic monolayers

• US 20080274413A1
• Filed: 03/22/2007
• Published: 11/06/2008
• Est. Priority Date: 03/22/2007
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Millward, Dan B.
• Granted Patent: US 8,557,128 B2
• Time in Patent Office: Days
• US Class Current: 430/5
• CPC Class Codes: B05D 3/007 After-treatment
• CPC Class Codes: B81C 1/00031 Regular or irregular arrays of nanoscale structures, e.g. etch mask layer photomechanical, e.g. photolithographic, production of textured or patterned surfaces G03F7/00; lithographic processes for making patterned surfaces using printing and stamping G03F7/0002
• CPC Class Codes: B81C 2201/0149 Forming nanoscale microstructures using auto-arranging or self-assembling material
• CPC Class Codes: B81C 2201/0198 for making a masking layer
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H01L 21/02002 Preparing wafers
• CPC Class Codes: H01L 21/3086 characterised by the process involved to create the mask, e.g. lift-off masks, sidewalls, or to modify the mask, e.g. pre-treatment, post-treatment
• CPC Class Codes: H01L 21/31144 using masks
• CPC Class Codes: Y10T 428/24 Structurally defined web or sheet [e.g., overall dimension, etc.]
• CPC Class Codes: Y10T 428/24149 Honeycomb-like
• CPC Class Codes: Y10T 428/24174 including sheet or component perpendicular to plane of web or sheet
• CPC Class Codes: Y10T 428/24521 with component conforming to contour of nonplanar surface
• CPC Class Codes: Y10T 428/2457 Parallel ribs and/or grooves
• CPC Class Codes: Y10T 428/24612 Composite web or sheet
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

Methods for fabricating sublithographic, nanoscale microchannels utilizing an aqueous emulsion of an amphiphilic agent and a water-soluble, hydrogel-forming polymer, and films and devices formed from these methods are provided.

Claims

1. A method for fabricating an etch mask on a substrate, comprising:

forming a layer of an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer in a trench having sidewalls and a floor, wherein the amphiphilic agent forms a layer selectively on the sidewalls of the trench and the polymer selectively wets the floor of the trench;

causing the polymer to form a hydrogel; and

removing the layer of the amphiphilic agent to form an opening between the hydrogel and the sidewalls of the trench and expose the floor of the trench.

2. The method of claim 1, wherein the opening between the hydrogel and the trench sidewalls is up to about 10 nm.

3. The method of claim 1, wherein the opening between the hydrogel and the trench sidewalls is about 3-10 nm.

4. The method of claim 1, further comprising removing a portion of the hydrogel to expose the layer of the amphiphilic agent within the trench.

5. The method of claim 4, further comprising drying the hydrogel prior to removing the hydrogel.

6. A method for fabricating an etch mask on a substrate, comprising:

depositing an aqueous emulsion comprising an amphiphilic surfactant and a water-soluble, hydrogel-forming polymer into a trench having hydrophobic sidewalls and a hydrophilic floor defined by a substrate, such that the surfactant forms a layer selectively on the sidewalls and the polymer orients selectively to the floor of the trench;

forming the polymer into a hydrogel; and

removing the surfactant layer to form a gap between the hydrogel and the trench sidewalls and expose the substrate at the floor of the trench.

7. The method of claim 6, wherein the polymer is selected from the group consisting of poly(ethylene oxide) and poly(ethylene glycol).

8. The method of claim 6, wherein the polymer is selected from the group consisting of poly(vinyl alcohol) and poly(saccharide).

9. A method for fabricating an etch mask on a substrate, comprising:

selectively forming a hydrophobic layer on sidewalls of a trench and a hydrophilic layer on a floor of the trench;

forming a layer of an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer in the trench, wherein the amphiphilic agent forms a layer selectively on the sidewalls of the trench and the polymer orients selectively to the floor of the trench;

causing the polymer to form a hydrogel; and

selectively removing the layer of the amphiphilic agent to form an opening between the hydrogel and the sidewalls of the trench and expose the floor of the trench.

10. The method of claim 9, wherein the trench sidewalls comprise hydrogen-terminated silicon.

11. The method of claim 9, wherein the trench floor comprise a hydrophilic polymer.

12. The method of claim 9, wherein forming the hydrophilic layer comprises grafting a hydrophilic polymer to the floor of the trench with reactive groups of the hydrophilic polymer oriented toward the center of the trench.

13. The method of claim 9, wherein ends of the trench are hydrophilic.

14. The method of claim 9, wherein the emulsion further comprises an organic solvent.

15. The method of claim 9, wherein the emulsion further comprises a hardening agent.

16. The method of claim 9, further comprising applying a silicon ester to the hydrogel to effect a sol-gel reaction.

17. A method for fabricating an etch mask on a substrate, comprising:

selectively forming a hydrophobic layer on sidewalls of a trench and a hydrophilic layer on a floor of the trench;

forming a layer of an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer in the trench, wherein the amphiphilic agent forms a layer selectively on the sidewalls of the trench and the polymer orients selectively to the floor of the trench;

crosslinking the polymer to form a hydrogel; and

removing the layer of the amphiphilic agent to form an opening between the hydrogel and the sidewalls of the trench and expose the floor of the trench.

18. The method of claim 17, wherein crosslinking the polymer comprises applying a catalyst onto the emulsion within the trench.

19. The method of claim 17, further comprising crosslinking the layer of the amphiphilic agent.

20. A method for fabricating an etch mask on a substrate, comprising:

forming a layer of a self-assembled lamellar-phase block copolymer within a first trench having sidewalls and a floor defined by a substrate;

selectively removing one of the blocks of the self-assembled layer to form openings in the layer exposing the substrate at the floor of the trench;

etching through the openings to form second trenches in the substrate, the second trenches having hydrophobic sidewalls and a hydrophilic floor;

depositing an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer into the second trenches such that the amphiphilic agent forms a layer selectively on the sidewalls and the polymer orients selectively to the floor of the second trenches;

forming the polymer into a hydrogel; and

removing the amphiphilic agent layer to form a gap between the hydrogel and the trench sidewalls and expose the substrate at the floor of the second trenches.

21. A method for fabricating an etch mask on a substrate, comprising:

forming a layer of a self-assembled, lamellar-phase block copolymer within a first trench defined by a substrate and having sidewalls that are preferential wetting to one block of the block copolymer, a floor that is neutral wetting to both blocks of the block copolymer, a width and a length, the self-assembled polymer layer comprising alternating lamellar blocks spanning the width of the trench and oriented perpendicular to the trench floor and substantially parallel to the sidewalls;

selectively removing one of the blocks of the self-assembled layer to form openings in the polymer layer exposing the substrate at the floor of the trench;

etching through the openings to form second trenches in the substrate, the second trenches having hydrophobic sidewalls and a hydrophilic floor;

depositing an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer into the second trenches such that the amphiphilic agent forms a layer selectively on the sidewalls and the polymer orients selectively to the floor of the second trenches;

forming the polymer into a hydrogel; and

removing the amphiphilic agent layer to form a gap between the hydrogel and the trench sidewalls and expose the substrate at the floor of the second trenches.

22. A method for fabricating an etch mask on a substrate, comprising:

forming a film comprising a self-assembled lamellar-phase block copolymer within a first trench in a substrate to a thickness of about L_o, the block copolymer comprising first and second polymer blocks, and the trench having sidewalls that are preferential wetting to one block of the block copolymer, a floor that is neutral wetting to both blocks of the block copolymer, a width of about nL_o and a length;

the self-assembled polymer film comprising a single array of perpendicular-oriented lamellar polymer domains spanning the width and extending the length of the trench in a substantially parallel orientation to the sidewalls;

selectively removing one of the blocks of the self-assembled layer to form openings in the polymer layer exposing the substrate at the floor of the trench;

etching through the openings to form second trenches in the substrate, the second trenches having hydrophobic sidewalls and a hydrophilic floor;

depositing an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer into the second trenches such that the amphiphilic agent forms a layer selectively on the sidewalls and the polymer orients selectively to the floor of the second trenches;

forming the polymer into a hydrogel; and

removing the amphiphilic agent layer to form a gap between the hydrogel and the trench sidewalls and expose the substrate at the floor of the second trenches.

23. A method for fabricating an etch mask on a substrate, comprising:

forming a material layer over a substrate having a surface being neutral wetting to both blocks of a lamellar-phase block copolymer;

forming a first trench in the material layer having a floor, sidewalls, ends, a width and a length, to expose the neutral wetting surface of the substrate at the floor of the first trench, the sidewalls being preferential wetting to one of the blocks of the lamellar-phase block copolymer;

forming a layer of the lamellar-phase block copolymer within the first trench;

causing the copolymer layer to self-assemble into a film comprising alternating lamellar blocks spanning the width of the trench and oriented perpendicular to the trench floor and substantially parallel to the sidewalls;

selectively removing one of the lamellar blocks of the self-assembled film to form openings exposing the substrate at the floor of the trench;

etching through the openings to form second trenches in the substrate, the second trenches having hydrophobic sidewalls and a hydrophilic floor;

depositing an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer into the second trenches wherein the amphiphilic agent forms a layer selectively on the sidewalls and the polymer selectively wets the floor of the second trenches;

causing the polymer to form a hydrogel; and

removing the layer of the amphiphilic agent to form a gap between the hydrogel and the trench sidewalls and expose the substrate at the floor of the second trenches.

24. The method of claim 23, wherein the neutral wetting surface on the substrate comprises hydrogen-terminated silicon.

25. The method of claim 23, wherein the neutral wetting surface on the substrate comprises a random copolymer.

26. The method of claim 23, wherein the sidewalls of the first trench comprise oxide.

27. The method of claim 23, wherein the sidewalls of the first trench comprise silicon nitride or silicon oxycarbide.

28. The method of claim 23, wherein the sidewalls of the first trench comprise a methacrylate-based moiety.

29. A method for fabricating channels in a substrate, comprising:

forming a layer of an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer in a trench having sidewalls and a floor, wherein the amphiphilic agent forms a layer selectively on the sidewalls of the trench and the polymer selectively wets the floor of the trench;

causing the polymer to form a hydrogel;

removing the layer of the amphiphilic agent to form an opening between the hydrogel and the sidewalls of the trench and expose the floor of the trench; and

etching an underlying substrate through the openings to form the channels in the substrate.

30. A method for fabricating an etch mask on a substrate, comprising:

forming a layer of an aqueous emulsion comprising an amphiphilic material in a trench having hydrophobic sidewalls and a floor, wherein the amphiphilic material forms a layer selectively on the sidewalls of the trench;

crosslinking the amphiphilic material layer;

drying the amphiphilic material layer;

filling the trench with an inorganic material; and

removing the amphiphilic material layer to form an opening between the inorganic material and the sidewalls of the trench and expose the floor of the trench.

31. The method of claim 30, wherein the inorganic material comprises a dielectric material.

32. The method of claim 30, further comprising, after filling the trench, removing a portion of the inorganic material and amphiphilic material above the trench to expose the amphiphilic material layer on the sidewalls of the trench.

33-38. -38. (canceled)