Positive resist composition and pattern formation method using the same

1. A positive resist composition comprising (A) a resin that increases solubility in an alkali developing solution by the action of an acid and includes a monocyclic or polycyclic alicyclic hydrocarbon structure, and includes a structure represented by the following formula (H):

wherein R 2c to R 4c each independently represents a hydrogen atom or a hydroxy group, provided that at least one of R 2c to R 4c represents a hydroxy group; and

(B-1) a compound represented by the following formula (I):

wherein R 1 represents an alkyl group, an alicyclic hydrocarbon group, a hydroxy group, a carboxy group, an alkoxy group, a halogen atom or a phenylthio group, which may be the same or different, when two or more R 1 's are present; R 2 represents an alkyl group, an alicyclic hydrocarbon group, a hydroxy group, a carboxy group, an alkoxy group, a halogen atom or a phenylthio group, which may be the same or different, when two or more R 2 's are present, provided that at least one of R 2 represents a fluorine atom, an alkyl group substituted with a fluorine atom, an alicyclic hydrocarbon group substituted with a fluorine atom, an alkoxy group substituted with a fluorine atom or a phenylthio group substituted with a fluorine atom; y 1 each independently represents an integer of from 0 to 5; y 2a represents an integer of from 1 to 5, provided that the total number of fluorine atoms included in (R 2 ) y2a is 4 or more; and Q 1 represents an alkyl group substituted with a fluorine atom, a cycloalkyl group substituted with a fluorine atom, an aryl group substituted with a fluorine atom or an aryl group substituted with a fluorinated alkyl group.

2. The positive resist composition as claimed in claim 1 , which further comprises a compound represented by following formula (II) or (III):

wherein R 4 represents an alkyl group, an alicyclic hydrocarbon group, a hydroxy group, a carboxy group or an alkoxy group, which may be the same or different, when two or more R 4 's are present; R 5 represents an alkyl group, an alicyclic hydrocarbon group, which may be the same or different, when two or more R 5 's are present, or when two or more R 5 's are present, two of R 5 's may be combined with each other to form a ring; R 6 represents an alkyl group, an alicyclic hydrocarbon group, a hydroxy group, a carboxy group or an alkoxy group, which may be the same or different, when two or more R 6 's are present; A represents an aromatic group; X 2 represents an integer of from 1 to 3; y 3 each independently represents an integer of from 0 to 5; y 4 each independently represents an integer of from 0 to 5; and Q 3 and Q 4 each represents an alkyl group substituted with a fluorine atom, a cycloalkyl group substituted with a fluorine atom, an aryl group substituted with a fluorine atom or an aryl group substituted with a fluorinated alkyl group.

3. The positive composition as claimed in claim 1 , which further comprises (D) a nitrogen-containing basic compound.

4. The positive resist composition as claimed in claim 1 , wherein the resin of component (A) is a resin containing an alkali-soluble group protected with a 2-alkyl-2-adamantyl group or a 1-adamantyl-1-alkylalkyl group.

5. A pattern formation method comprising the steps of forming a resist film using the positive resist composition as claimed in claim 1 , exposing the resist film, and developing the exposed resist film.

6. The positive resist composition as claimed in claim 1 , wherein in — Ph— R 1 )y 1 )2, the total number of fluorine atoms directly substituted to any one benzene ring is 4 or less.

7. A positive resist composition comprising:

(A) a resin that increases solubility in an alkali developing solution by the action of an acid and includes a monocyclic or polycyclic alicyclic hydrocarbon structure which is dihydroxyadamantane, and

(B-1) a compound represented by the following formula (I):

wherein R 1 represents an alkyl group, an alicyclic hydrocarbon group, a hydroxy group, a carboxy group, an alkoxy group, a halogen atom or a phenylthio group, which may be the same or different, when two or more R 1 's are present; R 2 represents an alkyl group, an alicyclic hydrocarbon group, a hydroxy group, a carboxy group, an alkoxy group, a halogen atom or a phenylthio group, which may be the same or different, when two or more R 2 's are present, provided that at least one of R 2 represents a fluorine atom, an alkyl group substituted with a fluorine atom, an alicyclic hydrocarbon group substituted with a fluorine atom, an alkoxy group substituted with a fluorine atom or a phenylthio group substituted with a fluorine atom; y 1 each independently represents an integer of from 0 to 5; y 2a represents an integer of from 1 to 5, provided that the total number of fluorine atoms included in (R 2 ) y2a is 4 or more; and Q 1 represents an alkyl group substituted with a fluorine atom, a cycloalkyl group substituted with a fluorine atom, an aryl group substituted with a fluorine atom or an aryl group substituted with a fluorinated alkyl group.