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

• US 8,557,128 B2
• Filed: 03/22/2007
• Issued: 10/15/2013
• Est. Priority Date: 03/22/2007
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Millward, Dan B.
• Primary Examiner(s): ALANKO, ANITA KAREN
• Application Number:
  US11/726,674
• Publication Number:
  US 20080274413A1
• Time in Patent Office: 2,399 Days
• Field of Search: 216/49
• US Class Current: 216/2
• 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 sub-lithographic, 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 in a trench an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer to selectively form the amphiphilic agent on sidewalls of the trench and to selectively wet a floor of the trench with the water-soluble, hydrogel-forming polymer;

causing the water-soluble, hydrogel-forming polymer to form a hydrogel; and

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

2. The method of claim 1, wherein removing the amphiphilic agent comprises removing the amphiphilic agent to define an opening between the hydrogel and the sidewalls of the trench, the opening having a width of up to about 10 nm.

3. The method of claim 1, wherein removing the amphiphilic agent comprises removing the amphiphilic agent to define an opening between the hydrogel and the sidewalls of the trench, the opening having a width of about 3 nm to about 10 nm.

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

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

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

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

forming the water-soluble, hydrogel-forming polymer into a hydrogel; and

removing the amphiphilic surfactant to define a gap between the hydrogel and the hydrophobic sidewalls of the trench and to expose the substrate at the hydrophilic floor of the trench.

7. The method of claim 6, wherein depositing an aqueous emulsion into a trench comprises depositing an aqueous emulsion into the trench, the aqueous emulsion comprising the amphiphilic surfactant and a water-soluble hydrogel-forming polymer selected from the group consisting of poly(ethylene oxide) and poly(ethylene glycol).

8. The method of claim 6, wherein depositing an aqueous emulsion into a trench comprises depositing an aqueous emulsion into the trench, the aqueous emulsion comprising the amphiphilic surfactant and a water-soluble, hydrogel-forming polymer 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 material on sidewalls of a trench;

selectively forming a hydrophilic material on a floor of the trench;

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

causing the water-soluble, hydrogel-forming polymer to form a hydrogel; and

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

10. The method of claim 9, wherein selectively forming a hydrophobic material on sidewalls of a trench comprises selectively forming the hydrophobic material on sidewalls of a trench comprising hydrogen-terminated silicon.

11. The method of claim 9, wherein selectively forming a hydrophilic material on a floor of the trench comprises selectively forming the hydrophilic material on the floor of the trench comprising a hydrophilic polymer.

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

13. The method of claim 9, wherein selectively forming a hydrophobic material on sidewalls of a trench comprises selectively forming the hydrophobic material on sidewalls of a trench comprising hydrophilic ends.

14. The method of claim 9, wherein forming in the trench an aqueous emulsion comprises forming in the trench an aqueous emulsion comprising the amphiphilic agent, the water-soluble, hydrogel-forming polymer, and an organic solvent.

15. The method of claim 9, wherein forming in the trench an aqueous emulsion comprises forming in the trench an aqueous emulsion comprising the amphiphilic agent, the water-soluble, hydrogel-forming polymer, and 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 material on sidewalls of a trench;

selectively forming a hydrophilic material on a floor of the trench;

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

crosslinking the water-soluble, hydrogel-forming polymer to form a hydrogel; and

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

18. The method of claim 17, wherein crosslinking the water-soluble, hydrogel-forming polymer comprises applying a catalyst onto the aqueous emulsion within the trench.

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

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

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

selectively removing a block of the self-assembled lamellar-phase block copolymer to define openings in the self-assembled lamellar-phase block copolymer and to expose the substrate at the floor of the first 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 to selectively form the amphiphilic agent on the hydrophobic sidewalls of the second trenches and to selectively orient the water-soluble, hydrogel-forming polymer to the hydrophilic floor of the second trenches;

forming the water-soluble, hydrogel-forming polymer into a hydrogel; and

removing the amphiphilic agent to define a gap between the hydrogel and the hydrophobic sidewalls of the second trenches and to expose the hydrophilic floor of the second trenches.

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

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

selectively removing one of the two blocks of the self-assembled, lamellar-phase block copolymer to define openings in the self-assembled, lamellar-phase block copolymer and to expose the substrate at the floor of the first trench;

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

depositing into the second trenches an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer to selectively form the amphiphilic agent on the hydrophobic sidewalls of the second trenches and to selectively orient the water-soluble, hydrogel-forming polymer to the hydrophilic floor of the second trenches;

forming the water-soluble, hydrogel-forming polymer into a hydrogel; and

removing the amphiphilic agent to define a gap between the hydrogel and the hydrophobic sidewalls of the second trenches and to expose the hydrophilic floor of the second trenches.

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

forming within a first trench a film to a thickness of about L_o , the film comprising a self-assembled lamellar-phase block copolymer comprising first and second polymer blocks, the first trench having sidewalls that are preferential wetting to one block of the first and second polymer blocks, a floor that is neutral wetting to both of the first and second polymer blocks, a width of about nL_o, and a length, the film comprising a single array of perpendicular-oriented lamellar polymer domains disturbed across the width and extending the length of the first trench in a substantially parallel orientation to the sidewalls;

selectively removing one of the first and second polymer blocks of the film to define openings in the film exposing a substrate at the floor of the first trench;

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

depositing into the second trenches an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer to selectively form the amphiphilic agent on the hydrophobic sidewalls of the second trenches and to selectively orient the water-soluble, hydrogel-forming polymer to the hydrophilic floor of the second trenches;

forming the water-soluble, hydrogel-forming polymer into a hydrogel; and

removing the amphiphilic agent to define a gap between the hydrogel and the hydrophobic sidewalls of the second trenches and to expose the hydrophilic floor of the second trenches.

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

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

forming a first trench in the material to expose the neutral wetting surface of the substrate at a floor of the first trench, the first trench comprising sidewalls being preferential wetting to one of the two blocks of the lamellar-phase block copolymer;

forming the lamellar-phase block copolymer within the first trench;

causing the lamellar-phase block copolymer to self assemble into a film comprising alternating lamellar blocks distributed across the width of the first trench, the alternating lamellar blocks oriented perpendicular to the floor of the first trench and substantially parallel to the sidewalls of the first trench;

selectively removing a lamellar block of the alternating lamellar blocks of the film to define openings exposing the substrate at the floor of the first trench;

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

depositing into the second trenches an aqueous emulsion comprising an amphiphilic agent and a water-soluble, hydrogel-forming polymer to selectively form the amphiphilic agent on the hydrophobic sidewalls of the second trenches and to selectively wet the hydrophilic floor of the second trenches with the water-soluble, hydrogel-forming polymer;

causing the water-soluble, hydrogel-forming polymer to form a hydrogel; and

removing the amphiphilic agent to define a gap between the hydrogel and the hydrophobic sidewalls of the second trenches and to expose the hydropholic floor of the second trenches.

24. The method of claim 23, wherein forming a material over a substrate comprises forming the material over a substrate having a neutral wetting surface comprising hydrogen-terminated silicon.

25. The method of claim 23, wherein forming a material over a substrate comprises forming the material over a substrate having a neutral wetting surface comprising a random copolymer.

26. The method of claim 23, wherein forming a first trench in the material comprises forming the first trench in an oxide material.

27. The method of claim 23, wherein forming a first trench in the material comprises forming the first trench in a silicon nitride or silicon oxycarbide material.

28. The method of claim 23, wherein forming a first trench in the material comprises forming in the material a first trench comprising sidewalls comprising a methacrylate-based moiety.

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

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

causing the water-soluble, hydrogel-forming polymer to form a hydrogel;

removing the amphiphilic agent to define openings between the hydrogel and the sidewalls of the trench and to expose the floor of the trench; and

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

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

forming in a trench an aqueous emulsion comprising an amphiphilic material to selectively form the amphiphilic material on hydrophobic sidewalls of the trench;

crosslinking the amphiphilic material;

drying the amphiphilic material;

filling the trench with an inorganic material; and

removing the amphiphilic material to define an opening between the inorganic material and the hydrophobic sidewalls of the trench and to expose a floor of the trench.

31. The method of claim 30, wherein filling the trench with an inorganic material comprises filling the trench with an inorganic material comprising a dielectric material.

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