Composition for resist pattern-refinement, and fine pattern-forming method
A composition for resist pattern-refinement includes an ion represented by formula (1-1), an ion represented by formula (1-2), an ion represented by formula (2-1), an ion represented by formula (2-2) and a solvent. A total amount of the ions blended is no less than 50% by mass with respect to a sum of components other than the solvent. R 1 represents a monovalent organic group having 1 to 30 carbon atoms or a fluorine atom; Z represents a single bond or a divalent linking group; R 2 represents a single bond, a divalent hydrocarbon group having 1 to 10 carbon atoms or a divalent fluorinated hydrocarbon group having 1 to 10 carbon atoms; M + represents a monovalent cation; and R 3 represents a monovalent organic group having 1 to 30 carbon atoms.
1. A composition for resist pattern-refinement comprising an ion represented by formula (1-1), an ion represented by formula (1-2), an ion represented by formula (2-1), an ion represented by formula (2-2) and a solvent,
a total amount of the ions blended being no less than 50% by mass with respect to a sum of components other than the solvent,
R 1 —Z—R 2 —SO 3 − (1-1)
M + (1-2)
R 3 —SO 3 − (2-1)
H + (2-2)
wherein,
in the formula (1-1), R 1 represents a monovalent organic group having 1 to 30 carbon atoms or a fluorine atom; Z represents a single bond or a divalent linking group; and R 2 represents a single bond, a divalent hydrocarbon group having 1 to 10 carbon atoms or a divalent fluorinated hydrocarbon group having 1 to 10 carbon atoms,
in the formula (1-2), M + represents a monovalent cation, and
in the formula (2-1), R 3 represents a monovalent organic group having 1 to 30 carbon atoms.
2. The composition for resist pattern-refinement according to claim 1 , wherein the ion represented by the formula (1-1) and the ion represented by the formula (1-2) are blended as a salt, and the ion represented by the formula (2-1) and the ion represented by the formula (2-2) are blended as a sulfonic acid.
3. The composition for resist pattern-refinement according to claim 2 , wherein the sulfonic acid is represented by formula (2):
R 3 —SO 3 H (2)
wherein, in the formula (2), R 3 is as defined in the formula (2-1).
4. The composition for resist pattern-refinement according to claim 2 , wherein a difference obtained by subtracting a pKa value of the sulfonic acid from a pKa value of a conjugate acid of the ion represented by the formula (1-1) is no less than −2 and no greater than 2.
5. The composition for resist pattern-refinement according to claim 2 , wherein the salt is represented by formula (1):
R 1 —Z—R 2 —SO 3 − M + (1)
wherein, in the formula (1), R 1 , Z and R 2 are each as defined in the formula (1-1); and M + is as defined in the formula (1-2).
6. The composition for resist pattern-refinement according to claim 1 , wherein the organic group represented by R 1 in the formula (1) comprises a ring structure having 5 to 20 ring atoms.
7. The composition for resist pattern-refinement according to claim 6 , wherein the ring structure is an alicyclic hydrocarbon structure.
8. A fine pattern-forming method comprising:
forming a resist pattern; and
refining the resist pattern with a composition for resist pattern-refinement, wherein
the composition for resist pattern-refinement according to claim 1 is used as the composition for resist pattern-refinement.
9. The fine pattern-forming method according to claim 8 , wherein the resist pattern is formed from a radiation-sensitive resin composition comprising a polymer comprising an acid-labile group, and a radiation-sensitive acid generator.
10. The fine pattern-forming method according to claim 8 , wherein the temperature of the composition for resist pattern-refinement in refining the resist pattern is no greater than 110° C.