Fluoro-alcohol additives for orientation control of block copolymers

Patent metadata

Field	Value
Publication number	US-9574107-B2
Application number	US-201514623395-A
Country	US
Kind code	B2
Filing date	Feb 16, 2015
Priority date	Feb 16, 2015
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

Abstract

A film layer comprising a high-chi (χ) block copolymer for self-assembly and a hexafluoroalcohol-containing surface active polymer (SAP) was prepared on a substrate surface that was neutral wetting to the domains of the self-assembled block copolymer. The block copolymer comprises at least one polycarbonate block and at least one other block (e.g., a substituted or unsubstituted styrene-based block). The film layer, whose top surface has contact with an atmosphere, self-assembles to form a lamellar or cylindrical domain pattern having perpendicular orientation with respect to the underlying surface. Other morphologies (e.g., islands and holes of height 1.0Lo) were obtained with films lacking the SAP. The SAP is preferentially miscible with, and lowers the surface energy of, the domain comprising the polycarbonate block.

First claim

What is claimed is:

1. A composition, comprising:
i) a solvent;
ii) a block copolymer comprising:
a) a first block comprising a repeat unit of formula (B-1):

wherein I) R w is a monovalent radical selected from the group consisting of H, methyl, ethyl, and trifluoromethyl (*—CF 3 ) and II) R d is a monovalent radical comprising an aromatic ring linked to carbon 1, and
b) an aliphatic polycarbonate second block (polycarbonate block) linked to the first block; and

iii) a surface active polymer (SAP) comprising a fluoro-alcohol repeat unit (HFA repeat unit), the HFA repeat unit comprising at least one hexafluoroisopropyl alcohol group (HFA group), the HFA group having a structure

wherein the block copolymer and the SAP are dissolved in the solvent.

2. The composition of claim 1 , wherein the composition is suitable for forming a layer for self-assembly (SA layer) disposed on an underlayer of a substrate, wherein
the SA layer comprises the block copolymer and the SAP in non-covalent association,
the SA layer has a top surface in contact with an atmosphere,
the underlayer is neutral wetting to the block copolymer,
the block copolymer of the SA layer is capable of self-assembly to form a phase separated domain pattern having a characteristic pitch Lo,
the domain pattern comprises alternating domains comprising respective chemically distinct blocks of the block copolymer,
each of the domains has contact with the underlayer and the atmosphere, and
a domain comprising the polycarbonate block (polycarbonate domain) has a higher concentration of the SAP compared to a domain comprising the first block of the block copolymer.

3. The composition of claim 2 , wherein the polycarbonate domain has lower surface energy compared to an otherwise identical polycarbonate domain lacking the SAP.

4. The composition of claim 2 , wherein the domain pattern comprises lamellar domains, and each of the lamellar domains has a perpendicular orientation to the underlayer.

5. The composition of claim 2 , wherein the domain pattern comprises cylindrical domains, and each of the cylindrical domains has a central axis oriented perpendicular to the underlayer.

6. The composition of claim 1 , wherein the SAP is a homopolymer of the HFA repeat unit.

7. The composition of claim 1 , wherein the HFA repeat unit is selected from the group consisting of:

8. The composition of claim 1 , wherein the SAP is a random copolymer comprising the HFA repeat unit.

9. The composition of claim 8 , wherein the random copolymer comprises a diluent repeat unit selected from the group consisting of

and combinations thereof, wherein each R″ is independently selected from the group consisting of *—H, *-Me, *-Et, and *—CF 3 , and each n′ is an independent integer of 1 to 12.

10. The composition of claim 1 , wherein the polycarbonate block of the block copolymer comprises a trimethylene carbonate repeat unit of structure:

11. The composition of claim 10 , wherein the polycarbonate block of the block copolymer is a homopolymer of the trimethylene carbonate repeat unit.

12. The composition of claim 1 , wherein the first block of the block copolymer comprises repeat units of structure:

13. The composition of claim 1 , wherein the first block of the block copolymer is poly(styrene) (PS) and the second block of the block copolymer is poly(trimethylene carbonate) (PTMC).

14. The composition of claim 1 , wherein the block copolymer is a triblock copolymer.

15. The composition of claim 14 , wherein the triblock copolymer comprises a divalent central poly(styrene) (PS) block linked at each end to two poly(trimethylene carbonate) (PTMC) blocks.

16. The composition of claim 1 , wherein the composition comprises the SAP in an amount of more than 0 wt %, and up to about 10 wt % based on a total dry solids weight of the composition.

17. The composition of claim 1 , wherein the composition comprises the SAP in an amount of 0.1 wt % to about 5 wt % based on total dry solids of the composition.

18. A method, comprising:
providing a first layered structure comprising a top layer (underlayer);
disposing the composition of claim 1 on the underlayer and removing any solvent, thereby forming a second layered structure comprising a film layer disposed on the underlayer, wherein the film layer comprises the block copolymer and the SAP in non-covalent association, and the film layer has a top surface in contact with an atmosphere, and wherein the block copolymer of the film layer comprises a) a first block comprising a repeat unit of formula (B-1):

wherein I) R w is a monovalent radical selected from the group consisting of H, methyl, ethyl, and trifluoromethyl (*—CF 3 ) and II) R d is a monovalent radical comprising an aromatic ring linked to carbon 1, and b) an aliphatic polycarbonate second block (polycarbonate block) linked to the first block, and the SAP of the film layer comprises a fluoro-alcohol repeat unit (HFA repeat unit), the HFA repeat unit comprising at least one hexafluoroisopropyl alcohol group (HFA group), the HFA group having a structure

and
allowing or inducing the block copolymer of the film layer to self-assemble, thereby forming a third layered structure comprising a phase separated domain pattern having a characteristic pitch Lo, the domain pattern comprising alternating domains comprising respective chemically distinct blocks of the block copolymer;

wherein
each of the domains has contact with the underlayer and the atmosphere, and
a domain comprising the polycarbonate block has a higher concentration of the SAP compared to a domain comprising the first block of the block copolymer.

19. The method of claim 18 , comprising selectively etching one of the domains, thereby forming a fourth layered structure comprising an etched domain pattern comprising one or more remaining domains.

20. The method of claim 18 , comprising transferring the etched domain pattern to the substrate using a wet and/or dry etch process.

21. The method of claim 18 , wherein the domain pattern is a lamellar domain pattern, and lamellae of each of the domains are oriented perpendicular to a main plane of the underlayer.

22. The method of claim 18 , wherein the domain pattern is a cylindrical domain pattern comprising cylindrical domains having a central axis oriented perpendicular to a main plane of the underlayer.

23. The method of claim 18 , wherein the underlayer comprises a random copolymer comprising:
a first repeat of structure:

and
a se

Assignees

• IBM

Inventors

• Cheng Joy
• Chunder Anindarupa
• Sanders Daniel P
• Tjio Melia
• Vora Ankit

Classifications

• H10P76/20

  of masks comprising organic materials · CPC title

• C08F112/20

  Fluorine · CPC title

• C08F112/24

  Phenols or alcohols · CPC title

• C08F8/30

  Introducing nitrogen atoms or nitrogen-containing groups · CPC title

• C08F8/00 Primary

  Chemical modification by after-treatment (graft polymers, block polymers, crosslinking with unsaturated monomers or with polymers C08F251/00 - C08F299/00; of conjugated diene rubbers C08C) · CPC title