Liquid immersion lithography upper-layer film-forming composition and photoresist pattern-forming method

Patent metadata

Field	Value
Publication number	US-9261789-B2
Application number	US-201113110855-A
Country	US
Kind code	B2
Filing date	May 18, 2011
Priority date	May 18, 2010
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

A liquid immersion lithography upper-layer film-forming composition includes (A) a polymer that includes a structural unit (I) shown by the following formula (1), and (S) a solvent. R 1 in the formula (1) represents a hydrogen atom, a methyl group, or a trifluoromethyl group. The polymer (A) preferably further includes a structural unit (II) that includes a sulfo group. The polymer (A) preferably further includes a structural unit (III) shown by the following formula (3). R 2 in the formula (3) represents a hydrogen atom, a methyl group, or a trifluoromethyl group. R 3 represents a linear or branched monovalent hydrocarbon group having 1 to 12 carbon atoms or a monovalent alicyclic group having 3 to 20 carbon atoms, provided that at least one hydrogen atom of the hydrocarbon group or the alicyclic group is substituted with a fluorine atom.

First claim

The invention claimed is:

1. A photoresist pattern-forming method comprising:
applying a photoresist composition to a substrate to form a photoresist film;
applying a composition to the photoresist film to form a liquid immersion lithography upper-layer film;
exposing the photoresist film and the liquid immersion lithography upper-layer film via an immersion medium and a mask having a given pattern, the immersion medium being disposed between the liquid immersion lithography upper-layer film and a lens; and
developing the photoresist film and the liquid immersion lithography upper-layer film that have been exposed,
wherein the composition comprises:
(A) a polymer that comprises a structural unit (I) shown by formula (1), a structural unit (II) that comprises a sulfo group, and a structural unit (III) shown by formula (3)
(B) a polymer that comprises the structural unit (I) and a structural unit (III) shown by formula (3), and has a fluorine atom content higher than a fluorine atom content of the polymer (A); and
(S) a solvent,

wherein R 1 represents a hydrogen atom, a methyl group, or a trifluoromethyl group,

wherein R 2 represents a hydrogen atom, a methyl group, or a trifluoromethyl group, and R 3 represents a linear or branched monovalent hydrocarbon group having 1 to 12 carbon atoms or a monovalent alicyclic group having 3 to 20 carbon atoms, provided that at least one hydrogen atom of the hydrocarbon group or the alicyclic group is substituted with a fluorine atom.

2. The photoresist pattern-forming method according to claim 1 , wherein the polymer (A) further comprises a structural unit (IV) shown by formula (4),

wherein R 4 represents a hydrogen atom, a methyl group, or a trifluoromethyl group, and R 5 represents a linear or branched monovalent hydrocarbon group having 1 to 12 carbon atoms or a monovalent alicyclic group having 3 to 20 carbon atoms.

3. The photoresist pattern-forming method according to claim 1 , wherein the polymer (B) further comprises includes a structural unit (IV) shown by formula (4),

wherein R 4 represents a hydrogen atom, a methyl group, or a trifluoromethyl group, and R 5 represents a linear or branched monovalent hydrocarbon group having 1 to 12 carbon atoms or a monovalent alicyclic group having 3 to 20 carbon atoms.

4. The photoresist pattern-forming method according to claim 1 , wherein the structural unit (II) comprises a structural unit shown by formula (2-1), a structural unit shown by (2-2), or both,

wherein R 6 and R 7 individually represent a hydrogen atom, a methyl group, or a trifluoromethyl group, and R 8 and R 9 each individually represent a single bond, a linear or branched divalent hydrocarbon group having 1 to 6 carbon atoms, a divalent alicyclic group having 4 to 12 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 12 carbon atoms.

5. The photoresist pattern-forming method according to claim 1 , wherein a content of the structural unit (I) in the polymer (A) is 20 to 99 mol % based on a total of structural units included in the polymer (A).

6. The photoresist pattern-forming method according to claim 1 , wherein a content of the structural unit (II) in the polymer (A) is 1 to 20 mol % based on a total of structural units included in the polymer (A).

7. The photoresist pattern-forming method according to claim 1 , wherein a content of the structural unit (III) in the polymer (B) is 5 to 80 mol % based on a total of structural units included in the polymer (A).

8. The photoresist pattern-forming method according to claim 1 , wherein the polymer (A) further comprises a structural unit (V) which is shown by formula (5-1) or formula (5-2),

wherein R 10 and R 11 each represent a hydrogen atom, a methyl group, or a trifluoromethyl group, R 12 represents a single bond, a linear or branched alkanediyl group having 1 to 6 carbon atoms which is other than a 1,2-ethylene group, or a divalent alicyclic group having 4 to 12 carbon atoms, R 13 represents a single bond, a linear or branched alkanediyl group having 1 to 6 carbon atoms, or a divalent alicyclic group having 4 to 12 carbon atoms, and R 14 represents a linear or branched hydrocarbon group having 1 to 10 carbon atoms or a monovalent alicyclic group having 3 to 10 carbon atoms, provided that at least one hydrogen atom of the hydrocarbon group or the alicyclic group represented by R 14 is substituted with a fluorine atom.

9. The photoresist pattern-forming method according to claim 1 , wherein a content of the polymer (A) in the composition is 20 mass % or more based on a total of polymers included in the composition.

10. The photoresist pattern-forming method according to claim 1 , wherein a content of the polymer (A) in the composition is 40 mass % or more based on a total of polymers included in the composition.

11. The photoresist pattern-forming method according to claim 1 , wherein a content of the polymer (A) in the composition is 60 mass % or more based on a total of polymers included in the composition.

12. The photoresist pattern-forming method according to claim 1 , wherein the composition further comprises (C) a polymer that comprises a structural unit (V) which is shown by formula (5-1) or formula (5-2), and the structural unit (III), the polymer (C) having a fluorine atom content higher than a fluorine content of the polymer (A),

wherein R 10 and R 11 each represent a hydrogen atom, a methyl group, or a trifluoromethyl group, R 12 represents a single bond, a linear or branched alkanediyl group having 1 to 6 carbon atoms which is other than a 1,2-ethylene group, or a divalent alicyclic group having 4 to 12 carbon atoms, R 13 represents a single bond, a linear or branched alkanediyl group having 1 to 6 carbon atoms, or a divalent alicyclic group having 4 to 12 carbon atoms, and R 14 represents a linear or branched hydrocarbon group having 1 to 10 carbon atoms or a monovalent alicyclic group having 3 to 10 carbon atoms, provided that at least one hydrogen atom of the hydrocarbon group or the alicyclic group represented by R 14 is substituted with a fluorine atom.

13. The photoresist pattern-forming method according to claim 12 , wherein the polymer (C) further comprises a structural unit (IV) shown by formula (4),

wherein R 4 represents a hydrogen atom, a methyl group, or a trifluoromethyl group, and R 5 represents a linear or branched monovalent hydrocarbon group having 1 to 12 carbon atoms or a monovalent alicyclic group having 3 to 20 carbon atoms.

Assignees

• Hayama Takahiro
• Kusabiraki Kazunori
• Nishimura Yukio
• Maruyama Ken
• Tanaka Kiyoshi
• Jsr Corp

Inventors

• Hayama Takahiro
• Kusabiraki Kazunori
• Nishimura Yukio
• Maruyama Ken
• Tanaka Kiyoshi

Classifications

• C08F228/02

  by a bond to sulfur · CPC title

• G03F7/2041

  in the presence of a fluid, e.g. immersion; using fluid cooling means · CPC title

• C08F220/30

  containing aromatic rings in the alcohol moiety · CPC title

• G03F7/0046

  with perfluoro compounds, e.g. for dry lithography (G03F7/0048 takes precedence) · CPC title

• C08F220/18

  with acrylic or methacrylic acids · CPC title