Positive-type resist composition and resist pattern formation method

Abstract

The present invention provides a technology which enables the formation of a high-contrast resist pattern that is suppressed in resist top loss. According to the present invention, a positive resist composition which contains a main chain scission type copolymer A containing a fluorine substituent, a main chain scission type acrylic (co)polymer B containing a fluorine substituent, and a solvent is used for the formation of a resist pattern. The difference between the surface free energy of the polymer A and the surface free energy of the acrylic (co)polymer B is 4 mJ / m2 or more. The acrylic (co)polymer B has a Gs value of 2.0 or less, the Gs value indicating the number of bonds that are broken in the acrylic (co)polymer B when irradiated with a γ-ray of 100 eV; and the acrylic (co)polymer B comprises a specific monomer unit.

Claims

1. A main chain cleavage type copolymer A containing a fluorine substituent, Acrylic (co)polymer B, which is a main-chain cleavage type containing a fluorine substituent, It contains a solvent, The copolymer A is a main-chain cleavage type copolymer containing fluorine substituents other than the acrylic (co)polymer B, and has monomer units (I) represented by the following formula (I) and monomer units (II) represented by the following formula (II). The value obtained by subtracting the surface free energy of the acrylic(co)polymer B from the surface free energy of copolymer A is 4 mJ / m². ２ That's all. The acrylic(co)polymer B is a positive-type resist composition in which, when irradiated with gamma rays, the Gs value, which represents the number of bonds broken in the acrylic(co)polymer B by the absorption of 100 eV of energy, is 2.0 or less, and the acrylic(co)polymer B has monomer units (III) represented by the following formula (III), or monomer units (IV) represented by the following formula (IV), and when the acrylic(co)polymer B has monomer units (IV), the proportion of monomer units (IV) in the total monomer units constituting the acrylic(co)polymer B is 60 mol% or more and 100 mol or less. 【Chemistry 1】 [In formula (I), L is a divalent linking group having a fluorine atom, and Ar is an aromatic ring group which may have substituents.] 【Chemistry 2】 [In formula (II), R1 is an alkyl group, R2 is a hydrogen atom, an alkyl group, a halogen atom, an alkyl halide, a hydroxyl group, or a carboxylic acid group, and p is an integer between 0 and 5. If there are multiple R2s, they may be the same or different from each other.] 【Transformation 3】 [In formula (III), R ３ This is an organic group that does not contain a hydrogen atom or a halogen atom, and R ４ This refers to an organic group having 3 to 7 fluorine atoms. 【Chemistry 4】 [In formula (IV), R ５ This is an organic group with five fluorine atoms.

2. A step of forming a resist film using the positive-type resist composition described in claim 1, The steps include: exposing the resist film, The process involves developing the exposed resist film using a developer solution, A method for forming a resist pattern, including the method described above.

3. The resist pattern forming method according to claim 2, wherein the developing solution is an alcohol.

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