Hybrid topographical and chemical pre-patterns for directed self-assembly of block copolymers

Patent metadata

Field	Value
Publication number	US-9738765-B2
Application number	US-201514626082-A
Country	US
Kind code	B2
Filing date	Feb 19, 2015
Priority date	Feb 19, 2015
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

Hybrid pre-patterns were prepared for directed self-assembly of a given block copolymer capable of forming a lamellar domain pattern. The hybrid pre-patterns have top surfaces comprising independent elevated surfaces interspersed with adjacent recessed surfaces. The elevated surfaces are neutral wetting to the domains formed by self-assembly. Material below the elevated surfaces has greater etch-resistance than material below the recessed surfaces in a given etch process. Following other dimensional constraints of the hybrid pre-pattern described herein, a layer of the given block copolymer was formed on the hybrid pre-pattern. Self-assembly of the layer produced a lamellar domain pattern comprising self-aligned, unidirectional, perpendicularly oriented lamellae over the elevated surfaces, and parallel and/or perpendicularly oriented lamellae over recessed surfaces. The domain patterns displayed long range order along the major axis of the pre-pattern. The lamellar domain patterns are useful in forming transfer patterns comprising two-dimensional customized features.

First claim

What is claimed is:

1. A method, comprising:
i) forming a layer for self-assembly, designated SA layer, comprising a material for self-assembly, designated SA material, on a top surface of a hybrid pre-pattern, and optionally forming a topcoat disposed on a top surface of the SA layer, wherein
the SA material is capable of self-assembling to form a phase separated lamellar domain pattern having a characteristic pitch Lo,
the hybrid pre-pattern is disposed on a substrate,
the top surface of the hybrid pre-pattern has a geometrical major axis,
the top surface of the hybrid pre-pattern comprises a) independent elevated surfaces interspersed with adjacent independent recessed surfaces and b) sidewalls joining elevated surfaces to recessed surfaces,
material underlying the elevated surfaces of the hybrid pre-pattern has greater etch-resistance in a given etch process compared to material underlying the recessed surfaces of the hybrid pre-pattern,
a given elevated surface has width W Ei defined as the length of the given elevated surface in a direction perpendicular to the major axis, wherein W Ei is greater than 0 nm and subscript i of W Ei is a number representing an index value denoting adjacency,
a given recessed surface has width W Ri defined as the length of the given recessed surface in a direction perpendicular to the major axis, wherein W Ri is greater than 0 nm and subscript i of W Ri is a number representing an index value denoting adjacency,
W Ri +W Ei of a given pair of adjacent recessed and elevated surfaces is an independent sum having a value of about nLo, meaning n times Lo, wherein n is an integer of 2 to about 30,
the hybrid pre-pattern comprises a recessed surface whose W Ri is greater than about 2 Lo,
the hybrid pre-pattern comprises an elevated surface whose W Ei is greater than about 2 Lo,
each of the sidewalls has an independent height H N of about 0.1 Lo to about 2 Lo,
the SA layer contacts the elevated surfaces, recessed surfaces, and sidewalls of the hybrid pre-pattern, and
the SA layer has a top surface in contact with an atmosphere or the topcoat;

ii) allowing or inducing the SA material to self-assemble, thereby forming a self-assembled SA layer comprising the lamellar domain pattern, the lamellar domain pattern comprising alternating lamellar domains comprising respective chemically distinct components of the SA material, each of the alternating lamellar domains comprising a plurality of lamellae, wherein
the elevated surfaces are neutral wetting to the domains,
each of the elevated surfaces contacts at least one of the lamellae of each of the domains,
each of the lamellae in contact with a given elevated surface of the hybrid pre-pattern a) is oriented perpendicular to the given elevated surface, b) is in contact with the atmosphere interface or the topcoat above the given elevated surface, and c) is aligned along the major axis of the hybrid pre-pattern,

iii) selectively removing one of the domains using an etch process, thereby forming an etched domain pattern comprising lamellae of a remaining domain; and
iv) selectively transferring the etched domain pattern into the material having greater etch-resistance below the elevated surfaces using a second etch process, thereby forming a transfer pattern comprising topographical features comprising the material of greater etch-resistance.

2. The method of claim 1 , wherein the method comprises selectively transferring the transfer pattern into one or more underlying layers of the substrate using a third etch process, thereby forming a second transfer pattern.

3. The method of claim 1 , wherein the sidewalls contact one domain of the self-assembled SA layer.

4. The method of claim 1 , wherein the recessed surfaces contact one domain of the self-assembled SA layer.

5. The method of claim 1 , wherein the sidewalls are non-neutral wetting to the domains of the self-assembled SA layer.

6. The method of claim 1 , wherein the sidewalls and recessed surfaces are non-neutral wetting to the domains of the self-assembled SA layer.

7. The method of claim 1 , wherein regions of the self-assembled SA layer located over respective underlying recessed surfaces of the hybrid pre-pattern comprise lamellae oriented perpendicular to the respective underlying recessed surfaces.

8. The method of claim 1 , wherein the etched domain pattern is a unidirectional line-space pattern having a pitch of about Lo.

9. The method of claim 1 , wherein the top surface of the hybrid pre-pattern comprises two or more regions comprising recessed surfaces having different values of W Ri .

10. The method of claim 1 , wherein the top surface of the hybrid pre-pattern comprises two or more regions having different values of W Ei +W Ri for a given pair of adjacent elevated and recessed surfaces.

11. The method of claim 1 , wherein the material below the elevated surfaces comprises an inorganic material.

12. The method of claim 1 , wherein the top surface of the SA layer contacts an atmosphere.

13. The method of claim 1 , wherein the top surface of the SA layer contacts a topcoat.

14. The method of claim 1 , wherein self-assembly of the SA layer forms a topcoat disposed on the SA layer.

15. The method of claim 1 , wherein H N is about 0.2 Lo to about 2 Lo.

16. The method of claim 1 , wherein the SA material comprises a block copolymer.

17. The method of claim 16 , wherein the block copolymer is poly(styrene-b-methyl methacrylate) block copolymer.

18. The method of claim 1 , wherein the top surface of the hybrid pre-pattern comprises two or more regions comprising elevated surfaces having different values of W Ei .

19. The method of claim 18 , wherein the two or more regions are along the major axis of the hybrid pre-pattern.

20. The method of claim 1 , wherein the material below the elevated surfaces comprises a resist.

21. The method of claim 20 , wherein the resist is a silsesquioxane.

22. A method, comprising:
i) forming a layer for self-assembly, designated SA layer, comprising a material suitable for self-assembly, designated SA material, on a top surface of a hybrid pre-pattern, and optionally forming a topcoat disposed on the SA layer, wherein
the SA material is capable of self-assembling to form a phase separated lamellar domain pattern having a characteristic pitch Lo,
the hybrid pre-pattern is disposed on a substrate,
the top surface of the hybrid pre-pattern has a geometrical major axis,
the top surface of the hybrid pre-pattern comprises a) independent elevated surfaces interspersed with adjacent independent recessed surfaces and b) sidewalls joining elevated surfaces to recessed surfaces,
material underlying the elevated surfaces of the hybrid pre-pattern has greater etch-resistance in a given etch process than material underlying the recessed surfaces of the hybrid pre-pattern,
a given elevated surface has a width W Ei defined as the length of the given elevated surface in a direction perpendicular to the major axis, wherein W Ei is greater than 0 nm and subscript i of W Ei is a number representing an index value denoting adjacency,
a given adjacent recessed surface has a width W Ri defined as the length of the recessed surface in a direction perpendicular to the major axis, wherein W Ri is greater than 0 nm and subscript i of W Ri is a number representing an index value denoting adjacency,
W Ri +W Ei of a given pair of adjacent recessed and elevated surfaces is an independent sum havi

Assignees

• IBM

Inventors

• Brink Markus
• Cheng Joy
• Doerk Gregory S
• Friz Alexander M
• Guillorn Michael A
• Liu Chi-Chun
• Sanders Daniel P
• Singh Gurpreet
• Tjio Melia
• Tsai Hsinyu

Classifications

• H10P76/4085

  characterised by the processes involved to create the masks · CPC title

• H10P14/6322

  Formation by thermal treatments (formation by plasma treatment H10P14/6319) · CPC title

• H10P14/683

  carbon-based polymeric organic materials, e.g. polyimides, poly cyclobutene or PVC · CPC title

• B05D1/185 Primary

  applying monomolecular layers (B05D1/204 takes precedence) · CPC title

• G03F7/0002

  Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping · CPC title