Positive resist composition and pattern-forming method using the same

1. A positive resist composition comprising:

(A) a resin capable of increasing a solubility thereof in an alkali developer by an action of an acid, the resin containing a repeating unit having a group having a lactone structure;

(B) a compound capable of generating a sulfonic acid represented by the following formula (I) upon irradiation with one of an actinic ray and a radiation; and

(C1) at least one of an amine compound having at least an aliphatic hydroxyl group in a molecule and an amine compound having at least an ether bond in a molecule:

A 1 A 2 -SO 3 H) n   (I)

wherein A 1 represents an n-valent linking group, A 2 represents a divalent aliphatic group, and A 2 's each may be the same or different, provided that at least one group represented by A 1 or A 2 contains a fluorine atom, and n represents an integer of from 2 to 4.

2. The positive resist composition according to claim 1 , wherein A 2 is an aliphatic group having a structure represented by the following formula (II):

wherein Rf 1 and Rf 2 each independently represents a hydrogen atom, a halogen atom, an alkyl group or a cycloalkyl group, provided that at least one of Rf 1 and Rf 2 represents a fluorine atom or a fluoroalkyl group.

3. The positive resist composition according to claim 1 , wherein the component (B) is a compound selected from a sulfonium salt compound, an iodonium salt compound and an ester compound of the sulfonic acid represented by the formula (I).

4. The positive resist composition according to claim 1 , wherein the amine compound of the component (C1) is at least a compound selected from structures represented by the following formulae (C-1), (C-2) and (C-3):

wherein Ra, Ra′ and Ra″ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group; Rb, Rb′, Rb″, Rc, Rc′ and Rc″ each may be the same or different in a case where a plurality of Rb, Rb′, Rb″, Rc, Rc′ and Rc are present, and each independently represents an alkylene group; Rd and Rd″ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group; and u, v, w, x and y each independently represents an integer of from 0 to 15.

5. The positive resist composition according to claim 1 , further comprising a surfactant.

6. A pattern-forming method comprising: forming a film from the positive resist composition according to claim 1 ; exposing the film; and developing the exposed film.

7. The positive resist composition according to claim 1 , wherein the component (A) is a resin having at least one repeating unit selected from the group consisting of a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by any of formulae (pI) to (pVI) and a repeating unit represented by formula (II-AB):

wherein R 11 represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group;

Z represents an atomic group necessary to form an alicyclic hydrocarbon group together with a carbon atom;

R 12 , R 13 , R 14 , R 15 and R 16 each independently represents a straight chain or a branched alkyl group having from 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R 12 , R 13 and R 14 , or either R 15 or R 16 , represents an alicyclic hydrocarbon group;

R 17 , R 18 , R 19 , R 20 and R 21 each independently represents a hydrogen atom, a straight chain or a branched alkyl group having from 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R 17 to R 21 represents an alicyclic hydrocarbon group, and either R 19 or R 21 represents a straight chain or a branched alkyl group having from 1 to 4 carbon atoms, or an alicyclic hydrocarbon group; and

R 22 , R 23 , R 24 and R 25 each independently represents a hydrogen atom, a straight chain or a branched alkyl group having from 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R 22 to R 25 represents an alicyclic hydrocarbon group, and R 23 and R 24 may be bonded to each other to form a ring:

wherein R 11 ′ and R 12 ′ each independently represents a hydrogen atom, a cyano group, a halogen atom or an alkyl group; and

Z′ contains at least two bonded carbon atoms (C—C) and represents an atomic group necessary to form an alicyclic structure.

8. The positive resist composition according to claim 1 , wherein the repeating unit having a group having a lactone structure of the component (A) is a repeating unit having a group having a lactone structure represented by formula (Lc) or any of formulae (V-1) to (V-5):

wherein R a1 , R b1 , R c1 , R d1 and R e1 each independently represents a hydrogen atom or an alkyl group;

m and n each independently represents an integer of from 0 to 3; and

m+n is from 2 to 6|

wherein R 1b , R 2b , R 3b , R 4b and R 5b each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxyl group, an alkoxycarbonyl group, an alkylsulfonyl-imino group, an alkenyl group, or —COOR a ;

R a represents an alkyl group; and

two of R 1b to R 5b may be bonded to each other to form a ring.

9. The positive resist composition according to claim 1 , wherein the resin (A) further contains a repeating unit represented by formula (VIII):

wherein Z 2 represents —O— or —N(R 41 )—;

R 41 represents a hydrogen atom, a hydroxyl group, an alkyl group or —OSO 2 —R 42 ; and

R 42 represents an alkyl group, a cycloalkyl group or a camphor residue, and the alkyl group represented by R 41 and R 42 may be substituted with a halogen atom.