Positive resist composition and method of pattern formation with the same

1. A resist composition for ArF exposure comprising:

(A) a resin which comes to have an enhanced solubility in an alkaline developing solution by an action of an acid;

(B) a compound which generates an acid upon irradiation with actinic rays or a radiation;

(C) a fluorine-containing compound containing at least one group selected from the groups (x) to (z):

(x) an alkali-soluble group;

(y) a group which decomposes by an action of an alkaline developing solution to enhance a solubility in an alkaline developing solution; and

(z) a group which decomposes by an action of an acid, and

(F) a solvent,

wherein the resin (A) has no fluorine atom and the fluorine-containing compound (C) is a resin containing a repeating unit represented by the following formula (C4):

in the formula (C4), X 11 represents an oxygen atom, R 11 's each independently represent a hydrogen atom, a halogen atom, or an alkyl group that may be linear or branched and may have one or more substituents, and

R 12 has a structure represented by formula (F3):

wherein R 62 and R 63 each independently represents a fluoroalkyl group, and

R 64 represents a hydrogen atom.

2. The resist composition for ArF exposure according to claim 1 ,

wherein R 62 is a trifluoromethyl group.

3. The resist composition for ArF exposure according to claim 1 ,

wherein R 62 and R 63 are a trifluoromethyl group.

4. The resist composition for ArF exposure according to claim 1 ,

wherein the fluorine-containing compound (C) has a molecular weight of from 1,000 to 100,000.

5. The resist composition for ArF exposure according to claim 1 ,

wherein the amount of the fluorine-containing compound (C) is from 0.1 to 5% by mass with respect to the total solid components in the positive resist composition.

6. The resist composition for ArF exposure according to claim 1 , which provides a film with which water has a receding contact angle of 70° or larger.

7. The resist composition for ArF exposure according to claim 1 ,

wherein the total solids concentration in the positive resist composition is from 1.0 to 6.0% by mass.

8. A pattern forming method, comprising:

forming a resist film by the resist composition for ArF exposure according to claim 1 , exposing the resist film; and

developing the exposed resist film.

9. The pattern forming method according to claim 8 ,

wherein the resist film is exposed to light having a wavelength of from 1 nm to 200 nm.

10. The pattern forming method according to claim 9 ,

wherein the exposing is an immersion exposure in which the resist film is exposed to light through an immersion liquid.

11. A method for manufacturing a semiconductor device comprising the pattern forming method according to claim 10 .