JP5050086B2 - Pattern formation method - Google Patents

Description

  The present invention relates to a pattern forming method used in a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal or a thermal head, and other photolithographic lithography processes. In particular, the present invention relates to a pattern forming method using a negative developing resist composition and a negative developer, which is preferably used in a lithography process in which exposure is performed with an immersion projection exposure apparatus.

With the miniaturization of semiconductor elements, the exposure light source has become shorter in wavelength and the projection lens has a higher numerical aperture (high NA). Currently, an exposure machine with an NA of 1.35 using an ArF excimer laser having a 193 nm wavelength as a light source has been developed. ing. These can be expressed by the following equations as is generally well known.
(Resolving power) = k ₁ · (λ / NA)
(Depth of focus) = ± k ₂ · λ / NA ²
Where λ is the wavelength of the exposure light source, NA is the numerical aperture of the projection lens, and k ₁ and k ₂ are coefficients related to the process.

As a technique for increasing the resolving power in an optical microscope, a so-called immersion method in which a high refractive index liquid (hereinafter also referred to as “immersion liquid” or “immersion medium”) is filled between a projection lens and a sample has been known. It has been. This “immersion effect” means that when λ ₀ is the wavelength of the exposure light in the air, n is the refractive index of the immersion liquid with respect to air, θ is the convergence angle of the light beam, and NA ₀ = sin θ. The above-described resolving power and depth of focus can be expressed by the following equations.
(Resolving power) = k ₁ · (λ ₀ / n) / NA ₀
(Depth of focus) = ± k ₂ · (λ ₀ / n) / NA ₀ ²
That is, the immersion effect is equivalent to using an exposure wavelength having a wavelength of 1 / n. In other words, in the case of a projection optical system with the same NA, the depth of focus can be increased n times by immersion. This is effective for all pattern shapes, and can be combined with a super-resolution technique such as a phase shift method and a modified illumination method which are currently being studied.

Examples of apparatuses in which this effect is applied to transfer of a fine image pattern of a semiconductor element include Patent Document 1 and Patent Document 2, but a resist suitable for immersion exposure technology is not discussed.
Recent progress in immersion exposure technology has been reported in Non-Patent Document 1, Non-Patent Document 2, Patent Document 3, Patent Document 4, and the like. When using an ArF excimer laser as a light source, pure water (refractive index of 1.44 at 193 nm) is the most promising immersion liquid in terms of handling safety and transmittance and refractive index at 193 nm. Has been applied. It is also known that high resolution can be obtained by immersion exposure using a medium having a higher refractive index as the immersion liquid (Non-patent Document 3).

  Since the resist for KrF excimer laser (248 nm), an image forming method called chemical amplification has been used as an image forming method for a resist in order to compensate for sensitivity reduction due to light absorption. An example of a positive chemical amplification image forming method is as follows. The acid generator in the exposed area is decomposed by exposure to generate acid, and the generated acid is used as a reaction catalyst in post-exposure baking (PEB). This is an image forming method in which an alkali-insoluble group is changed to an alkali-soluble group by use and an exposed portion is removed by alkali development.

It is pointed out that when chemically amplified resist is applied to immersion exposure, the resist layer comes into contact with the immersion liquid at the time of exposure, so that the resist layer is altered and components that adversely affect the immersion liquid are leached from the resist layer. Has been. Patent Document 4 describes an example in which resist performance is changed by immersing a resist for ArF exposure in water before and after exposure, and points out a problem in immersion exposure.
In addition, in the immersion exposure process, when exposure is performed using a scanning type immersion exposure machine, the exposure speed decreases if the immersion liquid does not move following the movement of the lens. There are concerns about the impact. In the case where the immersion liquid is water, it is desirable that the resist film be hydrophobic so that water followability is better. On the other hand, when the resist film is hydrophobized, the amount of resist residue (also referred to as scum) is generated. There was an adverse effect on the image performance of the resist, such as an increase, and an improvement was desired.

Currently, as a developing solution for g-line, i-line, KrF, ArF, EB, and EUV lithography, an aqueous alkaline developer solution of 2.38% by mass TMAH (tetramethylammonium hydroxide) is widely used.
As a developer other than the above, for example, Patent Document 5 discloses an acetic acid group or a ketone group for dissolving and developing an exposed portion of a resist material that is polymerized by irradiation with radiation to be polymerized. A developer having at least two ether groups and phenyl groups and having a molecular weight of 150 or more is described. Patent Document 6 and Patent Document 7 disclose a supercritical fluid, a halogenated organic solvent, or a non-halogenated organic solvent for dissolving and developing an exposed portion of a resist material containing a specific resin containing a fluorine atom. Developers selected from are described.
However, as the semiconductor element becomes finer, it becomes extremely difficult to find an appropriate combination of a resist composition, a developer, and the like for forming a pattern having an overall good performance. For example, scum after development There is a need to find a pattern forming method that can be suitably applied to immersion lithography, in which generation is reduced, line edge roughness and line width uniformity are excellent, and followability to immersion liquid is good. It was.

JP-A-57-153433 JP-A-7-220990 International Publication No. 04/077158 International Publication No. 04/068242 JP 2006-227174 A Special Table 2002-525683 JP-T-2005-533907

Proc. SPIE, 2002, Vol. 4688, p. 11 J.Vac.Sci.Tecnol.B 17 (1999) Nikkei Microdevices, March 2005

  The present invention solves the above-mentioned problems and reduces the occurrence of scum after development in order to stably form a high-precision fine pattern for manufacturing highly integrated and high-precision electronic devices. It is an object of the present invention to provide a pattern forming method with good followability to an immersion liquid with reduced in-plane uniformity of roughness and line width.

一般式（ｐＡ−ｃ）に於いて、
Ｒｐ₂は、式中の酸素原子に結合している３級炭素原子を有する炭化水素基を表す。
＜２＞ （Ｄ）成分が、フッ素化アルコール基、ラクトン基、及び、−Ｃ(Ｒ_３６)(Ｒ_３７)(Ｒ_３８)で表される基のいずれかを有する上記＜１＞に記載のパターン形成方法。
なお、Ｒ_３６〜Ｒ_３８は、各々独立に、アルキル基、シクロアルキル基、アリール基、アラルキル基又はアルケニル基を表し、Ｒ_３６とＲ_３７とは、互いに結合して環を形成してもよい。
＜３＞ 前記ネガ型現像液が含有する有機溶剤が、エステル系溶剤を含む上記＜１＞又は＜２＞に記載のパターン形成方法。
＜４＞ 前記ネガ型現像液を用いて現像後、有機溶剤を含むリンス液を用いて洗浄することを含む上記＜１＞〜＜３＞のいずれか一項に記載のパターン形成方法。
＜５＞ 前記露光を、２００ｎｍ以下の波長の光を用いて行う上記＜１＞〜＜４＞のいずれか一項に記載のパターン形成方法。
＜６＞前記液浸媒体が水である上記＜１＞〜＜５＞のいずれか一項に記載のパターン形成方法。
＜７＞ 前記レジスト組成物の（Ａ）成分が、単環又は多環の脂環炭化水素構造を有する樹脂である上記＜１＞〜＜６＞のいずれか一項に記載のパターン形成方法。
＜８＞ 前記レジスト組成物の（Ａ）成分が、ラクトン基有する、単環又は多環の脂環炭化水素構造を有する樹脂である上記＜７＞に記載のパターン形成方法。
なお、本発明は、上記＜１＞〜＜８＞に係る発明であるが、以下、その他についても参考のため記載した。 The present invention has the following configuration, whereby the above object of the present invention is achieved.
<1> Contains a resin whose polarity is increased by the action of an acid, and the solubility in a positive developer that is an alkaline developer increases upon irradiation with actinic rays or radiation, and the solubility in a negative developer that contains an organic solvent. Forming a resist film by applying a negative developing resist composition, exposing the resist film through an immersion medium, and developing using the negative developer. A pattern forming method comprising: the negative developing resist composition comprising the following components:
(A) a resin whose polarity is increased by the action of an acid, the solubility in the positive developer is increased by irradiation with actinic rays or radiation, and the solubility in the negative developer is decreased; (B) actinic rays or radiation A compound that generates an acid upon irradiation of (C), (C) a solvent, and (D) at least one of a fluorine atom and a silicon atom, and (x) an alkali-soluble group, and (y) decomposed by the action of an alkali developer. A group that increases the solubility in an alkali developer, (z) a group that decomposes by the action of an acid and increases the solubility in an alkali developer, and a repeating unit represented by the general formula (pA-c). Resin having either.

In the general formula (pA-c),
Rp ₂ represents a hydrocarbon group having a tertiary carbon atom bonded to the oxygen atom in the formula.
<2> The component (D) according to <1>, wherein the component has any one of a fluorinated alcohol group, a lactone group, and a group represented by -C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ). Pattern forming method.
R _{36 to} R ₃₈ each independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group, and R ₃₆ and R ₃₇ may be bonded to each other to form a ring. .
<3> The pattern forming method according to <1> or <2>, wherein the organic solvent contained in the negative developer includes an ester solvent.
<4> The pattern forming method according to any one of the above items <1> to <3>, comprising washing with a rinsing solution containing an organic solvent after development using the negative developer.
<5> The pattern forming method according to any one of <1> to <4>, wherein the exposure is performed using light having a wavelength of 200 nm or less.
<6> The pattern forming method according to any one of <1> to <5>, wherein the immersion medium is water.
<7> The pattern forming method according to any one of <1> to <6>, wherein the component (A) of the resist composition is a resin having a monocyclic or polycyclic alicyclic hydrocarbon structure.
<8> The pattern forming method according to <7>, wherein the component (A) of the resist composition is a resin having a lactone group and having a monocyclic or polycyclic alicyclic hydrocarbon structure.
In addition, although this invention is invention concerning said <1>-<8>, hereafter, it described for reference also about others.

(1) (a) Negative development, which contains a resin whose polarity is increased by the action of an acid, and the solubility in a positive developer is increased and the solubility in a negative developer is decreased by irradiation with actinic rays or radiation. Applying a resist composition for forming a resist film having a receding contact angle with respect to water of 70 degrees or more,
(A) A pattern forming method comprising: a step of exposing through an immersion medium; and (c) a step of developing using a negative developer.

(2) The negative developing resist composition is
(A) a resin whose polarity is increased by the action of an acid, the solubility in a positive developer is increased by irradiation with actinic rays or radiation, and the solubility in a negative developer is decreased;
(B) a compound that generates an acid upon irradiation with actinic rays or radiation,
(C) a solvent, and (D) a resin having at least one of a fluorine atom and a silicon atom,
(4) The pattern forming method as described in (1) above.

(3) (a ′) a negative type resin containing a resin whose polarity is increased by the action of an acid, and increased in solubility in a positive developer and reduced in negative developer by irradiation with actinic rays or radiation. Applying a developing resist composition;
(I) a pattern forming method comprising: a step of exposing through an immersion medium; and (c) a step of developing using a negative developer, wherein the negative developing resist composition comprises the following components: A pattern forming method comprising:
(A) a resin whose polarity is increased by the action of an acid, the solubility in a positive developer is increased by irradiation with actinic rays or radiation, and the solubility in a negative developer is decreased;
(B) a compound that generates an acid upon irradiation with actinic rays or radiation,
(C) a solvent, and (D) a resin having at least one of a fluorine atom and a silicon atom.

一般式（Ｆ３ａ）に於いて、
Ｒ_62a及びＲ_63aは、各々独立に、少なくとも１つの水素原子がフッ素原子で置換されたアルキル基を表す。Ｒ_62aとＲ_63aは、互いに連結して環を形成してもよい。
Ｒ_64aは、水素原子、フッ素原子又はアルキル基を表す。 (4) The pattern forming method as described in (2) or (3), wherein the resin (D) has a group represented by the following general formula (F3a).

In general formula (F3a),
R _62a and R _63a each independently represents an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom. R _62a and R _63a may be connected to each other to form a ring.
R _64a represents a hydrogen atom, a fluorine atom or an alkyl group.

一般式（ＣＳ−１）〜（ＣＳ−３）に於いて、
Ｒ₁₂〜Ｒ₂₆は、各々独立に、直鎖若しくは分岐アルキル基又はシクロアルキル基を表す。
Ｌ₃〜Ｌ₅は、単結合又は２価の連結基を表す。
ｎは１〜５の整数を表す。 (5) The pattern formation according to any one of (2) to (4), wherein the resin (D) has groups represented by the following general formulas (CS-1) to (CS-3): Method.

In general formulas (CS-1) to (CS-3),
R _{12 to} R ₂₆ each independently represents a linear or branched alkyl group or a cycloalkyl group.
L < ₃ > -L < ₅ > represents a single bond or a bivalent coupling group.
n represents an integer of 1 to 5.

(6) (c) Any of (1) to (5), wherein the step of developing using a negative developer is a step of developing using a developer containing an organic solvent. The pattern forming method according to 1.

(7) The pattern forming method as described in any one of (1) to (6), further comprising (d) a step of developing using a positive developer.

  The preferred embodiments of the present invention will be further described below.

(8) (c) The step of developing using a negative developer is performed using a negative developer containing at least one solvent selected from organic solvents having a vapor pressure of 5 kPa or less at 20 ° C. The pattern forming method according to any one of (1) to (7), wherein

(9) The pattern forming method as described in (8), wherein the organic solvent having a vapor pressure at 20 ° C. of 5 kPa or less is a ketone solvent, an ester solvent and an ether solvent.

(10) The pattern forming method as described in (8) or (9), wherein the organic solvent having a vapor pressure at 20 ° C. of 5 kPa or less is an ester solvent.

(11) The pattern forming method as described in any one of (8) to (10), wherein the organic solvent having a vapor pressure at 20 ° C. of 5 kPa or less is butyl acetate.

(12) (c) After the step of developing with a negative developer, the method further includes (e) a step of washing with a rinsing solution containing an organic solvent. The pattern formation method in any one of.

(13) (e) The rinsing liquid used in the step of washing with a rinsing liquid containing an organic solvent is a hydrocarbon solvent, a ketone solvent, an ester solvent, an alcohol solvent, an amide solvent, and an ether solvent. The pattern forming method according to (12), comprising at least one selected organic solvent.

(14) (e) The rinse liquid used in the step of washing with a rinse liquid containing an organic solvent contains at least one organic solvent selected from an ester solvent and an alcohol solvent. (12) The pattern formation method as described in (13).

(15) The pattern according to any one of (12) to (14), wherein the rinse liquid used in the step of washing with a rinse liquid containing an organic solvent contains a monohydric alcohol. Forming method.

(16) (e) The rinsing solution used in the step of washing with a rinsing solution containing an organic solvent has (v) at least one developer component used in the step of developing with a negative developer. The pattern forming method as described in any one of (12) to (15).

(17) (c) The step of developing using a negative developer includes a step of supplying a negative developer onto the surface of the substrate while rotating the substrate (1) to (16) ) The pattern forming method according to any one of the above.

(18) (e) The step of cleaning with a rinsing liquid containing an organic solvent includes a step of supplying a rinsing liquid onto the surface of the substrate while rotating the substrate (12) to (17). The pattern formation method in any one of.

(19) (d) The step of developing using a positive developer is at least one selected from the group consisting of primary amine compounds, secondary amine compounds, tertiary amine compounds and quaternary amine compounds. The pattern forming method as described in (7), which is a step performed using a developer containing an aqueous solution containing types.

(20) (D) The pattern described in (19), wherein the step of developing using a positive developer is a step of using a developer containing an aqueous solution of tetramethylammonium hydroxide. Forming method.

(21) The pattern forming method as described in (19) or (20), wherein the concentration of the amine compound in the developer is 0.01 to 20% by weight based on the total weight of the developer.

(22) (d) The method according to any one of (7) or (19) to (21), further including (f) a rinsing step after the step of developing using a positive developer. Pattern forming method.

(23) The pattern forming method as described in (22), wherein the rinse liquid used in the (f) rinsing step is pure water.

(24) The pattern forming method according to any one of (1) to (23), wherein exposure is performed using light having a wavelength of 200 nm or less.

(25) The pattern forming method according to any one of (1) to (24), wherein the immersion medium is water.

(26) The pattern forming method according to any one of (1) to (25), further comprising (i) a heating step after the step of exposing through the immersion medium.

(27) The pattern forming method as described in any one of (2) to (26), wherein the component (D) of the resist composition is a resin that is stable to acids and insoluble in an alkaline developer. .

(28) The pattern forming method as described in (27), wherein the component (D) of the resist composition is a resin soluble in a negative developer.

(29) The total amount of repeating units having an alkali-soluble group in the component (D) of the resist composition or a group whose solubility in the developer is increased by the action of an acid or alkali is the total repeating unit constituting the component (D). On the other hand, it is 20 mol% or less, The pattern formation method in any one of (2)-(28) characterized by the above-mentioned.

(30) The addition amount of component (D) of the resist composition is 0.1 to 5% by mass with respect to the total solid content in the resist composition. (2) to (29) The pattern formation method in any one.

(31) Any of (2) to (30), wherein the (D) component of the resist composition is any resin selected from the following (D-1) to (D-6) The pattern forming method according to 1.
(D-1) A resin having a repeating unit (a) having a fluoroalkyl group.
(D-2) A resin having a repeating unit (b) having a trialkylsilyl group or a cyclic siloxane structure.
(D-3) Resin having a repeating unit (a) having a fluoroalkyl group and a repeating unit (c) having a branched alkyl group, a cycloalkyl group, a branched alkenyl group, a cycloalkenyl group or an aryl group .
(D-4) a repeating unit (b) having a trialkylsilyl group or a cyclic siloxane structure and a repeating unit having a branched alkyl group, cycloalkyl group, branched alkenyl group, cycloalkenyl group or aryl group (c ).
(D-5) A resin having a repeating unit (a) having a fluoroalkyl group and a repeating unit (b) having a trialkylsilyl group or a cyclic siloxane structure.
(D-6) a repeating unit (a) having a fluoroalkyl group, a repeating unit (b) having a trialkylsilyl group or a cyclic siloxane structure, a branched alkyl group, a cycloalkyl group, a branched alkenyl group, A resin having a repeating unit (c) having a cycloalkenyl group or an aryl group.

一般式（Ｉａ）に於いて、
Ｒｆは、水素原子、フッ素原子又は少なくとも１つの水素原子がフッ素原子で置換されたアルキル基を表す。
Ｒ₁は、アルキル基を表す。
Ｒ₂は、水素原子又はアルキル基を表す。 (32) The pattern forming method as described in any one of (2) to (31), wherein the component (D) of the resist composition has a repeating unit represented by the following general formula (Ia).

In general formula (Ia):
Rf represents a hydrogen atom, a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom.
R ₁ represents an alkyl group.
R ₂ represents a hydrogen atom or an alkyl group.

一般式（ＩＩ）及び（ＩＩＩ）に於いて、
Ｒｆは、水素原子、フッ素原子又は少なくとも１つの水素原子がフッ素原子で置換されたアルキル基を表す。
Ｒ₃は、アルキル基、シクロアルキル基、アルケニル基又はシクロアルケニル基を表す。
Ｒ₄は、アルキル基、シクロアルキル基、アルケニル基、シクロアルケニル基、トリアルキルシリル基又は環状シロキサン構造を有する基を表す。
Ｌ₆は、単結合又は２価の連結基を表す。ｍは０以上１００以下の数値であり、ｎは０以上１００以下の数値である。 (33) The component (D) of the resist composition has a repeating unit represented by the following general formula (II) and a repeating unit represented by the following general formula (III) (2) to ( 32) The pattern forming method according to any one of the above.

In general formulas (II) and (III):
Rf represents a hydrogen atom, a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom.
R ₃ represents an alkyl group, a cycloalkyl group, an alkenyl group or a cycloalkenyl group.
R ₄ represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, a trialkylsilyl group, or a group having a cyclic siloxane structure.
L ₆ represents a single bond or a divalent linking group. m is a numerical value from 0 to 100, and n is a numerical value from 0 to 100.

(34) The pattern forming method as described in any one of (1) to (33), wherein the component (A) of the resist composition is a resin having an alicyclic hydrocarbon structure.

一般式（ｐＩ）〜（ｐＶ）中、
Ｒ₁₁は、メチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、イソブチル基又はｓｅｃ−ブチル基を表し、Ｚは、炭素原子とともにシクロアルキル基を形成するのに必要な原子団を表す。
Ｒ₁₂〜Ｒ₁₆は、各々独立に、炭素数１〜４個の、直鎖若しくは分岐のアルキル基又はシクロアルキル基を表す。但し、Ｒ₁₂〜Ｒ₁₄のうち少なくとも１つ、若しくはＲ₁₅、Ｒ₁₆のいずれかはシクロアルキル基を表す。
Ｒ₁₇〜Ｒ₂₁は、各々独立に、水素原子、炭素数１〜４個の、直鎖若しくは分岐のアルキル基又はシクロアルキル基を表す。但し、Ｒ₁₇〜Ｒ₂₁のうち少なくとも１つはシクロアルキル基を表す。また、Ｒ₁₉、Ｒ₂₁のいずれかは炭素数１〜４個の、直鎖若しくは分岐のアルキル基又はシクロアルキル基を表す。
Ｒ₂₂〜Ｒ₂₅は、各々独立に、水素原子、炭素数１〜４個の、直鎖若しくは分岐のアルキル基又はシクロアルキル基を表す。但し、Ｒ₂₂〜Ｒ₂₅のうち少なくとも１つはシクロアルキル基を表す。また、Ｒ₂₃とＲ₂₄は、互いに結合して環を形成していてもよい。 (35) The side chain of the component (A) of the resist composition is a resin having a partial structure containing an alicyclic hydrocarbon represented by the following general formula (pI) to general formula (pV): The pattern forming method according to any one of (1) to (34).

In general formulas (pI) to (pV),
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, and Z is an atom necessary for forming a cycloalkyl group together with a carbon atom. Represents a group.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or cycloalkyl group having 1 to 4 carbon atoms. However, at least one of R _{12 to} R ₁₄ , or any of R ₁₅ and R ₁₆ represents a cycloalkyl group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a cycloalkyl group. However, at least one of R _{17 to} R ₂₁ represents a cycloalkyl group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or cycloalkyl group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a cycloalkyl group. However, at least one of R _{22 to} R ₂₅ represents a cycloalkyl group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

(36) The pattern forming method as described in any one of (1) to (35) above, wherein the weight average molecular weight of the component (A) of the resist composition is 1,000 to 200,000.

(37) The pattern forming method as described in any one of (34) to (36), wherein the component (A) of the resist composition is an alicyclic hydrocarbon-based acid-decomposable resin having a lactone structure. .

(38) The pattern forming method according to any one of (1) to (37), wherein the resist composition further contains a basic compound.

(39) The pattern forming method as described in any one of (1) to (38), wherein the resist composition further contains a fluorine-based and / or silicon-based surfactant.
(40) The pattern forming method as described in any one of (1) to (39), wherein the solvent (C) is two or more kinds of mixed solvents containing propylene glycol monomethyl ether acetate.

  According to the present invention, it is possible to provide a pattern forming method with high accuracy, reduced generation of scum after development, and good in-plane uniformity of line edge roughness and line width.

It is a schematic diagram showing the relationship between the positive development, the negative development and the exposure amount in the conventional method. It is a schematic diagram showing a pattern forming method using both positive development and negative development. It is a schematic diagram which shows the relationship between positive image development, negative image development, and exposure amount. It is the schematic of the evaluation method of water followability.

Hereinafter, the best mode for carrying out the present invention will be described.
In addition, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes the thing which has a substituent with the thing which does not have a substituent. . For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

  First, terms used in this specification will be described. There are two types of pattern formation methods: positive and negative. Both use the fact that the solubility of the resist film in the developer changes due to a chemical reaction triggered by light irradiation. The case where the part is dissolved in the developer is called a positive type, and the case where the non-irradiated part is dissolved in the developer is called a negative type. There are two types of developers used in this case, a positive developer and a negative developer. The positive developer is a developer that selectively dissolves and removes the exposed portion above the predetermined threshold indicated by the solid line in FIG. 1, and the negative developer selects the exposed portion below the predetermined threshold. It is a developer that is dissolved and removed. The development process using a positive developer is referred to as positive development (also referred to as a positive development process), and the development process using a negative developer is referred to as a negative development (also referred to as a negative development process). Call. Multiple development (also referred to as multiple development process) is a development system in which the development process using the positive developer and the development process using the negative developer are combined. In the present invention, the resist composition used for negative development is called a negative development resist composition, and the resist composition used for multiple development is called a multiple development resist composition. Hereinafter, when it is simply described as a resist composition, it means a negative developing resist composition. The negative type rinsing liquid represents a rinsing liquid containing an organic solvent, which is used in the washing step after the negative type developing step.

  In the present invention, as a suitable technique for pattern formation in immersion lithography, (a) a resin whose polarity is increased by the action of an acid is contained, and the solubility in a positive developer is increased by irradiation with actinic rays or radiation. And a step of applying a resist composition for negative development whose solubility in the negative developer is reduced, and forming a resist film having a receding contact angle of 70 degrees or more with respect to water, (a) exposure through an immersion medium And (c) a new pattern that combines, as shown in FIG. 2, a step of developing with a negative developer that selectively dissolves and removes exposed portions below a predetermined threshold (b). It contains a resin whose polarity is increased by the formation method or the action of (a ') acid, and its solubility in a positive developer is increased by irradiation with actinic rays or radiation, so that it is dissolved in a negative developer. Forming a resist composition for negative development, (a) exposing through an immersion medium, and (c) developing using a negative developer In the negative developing resist composition, (A) the polarity is increased by the action of the acid, and the solubility in the positive developing solution is increased by irradiation with actinic rays or radiation, so that the solubility in the negative developing solution is increased. (B) a compound that generates an acid upon irradiation with actinic rays or radiation, (C) a solvent, and (D) a resin having at least one of a fluorine atom and a silicon atom. A new pattern formation method is presented.

  In carrying out the present invention, (i) a resist composition for negative development that contains a resin whose polarity is increased by the action of an acid, increases the solubility in a positive developer, and decreases the solubility in a negative developer. , (Ii) a negative developer (preferably an organic developer). As the above (i) negative developing resist composition, a resist composition which forms a resist film having a receding contact angle with respect to water of 70 degrees or more, or (A) the polarity is increased by the action of an acid, actinic rays or radiation Irradiation increases the solubility in a positive developer and decreases the solubility in a negative developer, (B) a compound that generates acid upon irradiation with actinic rays or radiation, (C) a solvent, and (D) There is a need for a resist composition containing a resin having at least one of a fluorine atom and a silicon atom.

  In order to carry out the present invention, it is further preferable to use (iii) a positive developer (preferably an alkali developer).

In order to carry out the present invention, it is preferable to further use (iv) a negative developing rinse solution containing an organic solvent.

The resist composition for negative development used in the present invention contains a resin whose polarity is increased by the action of an acid, and its solubility in a positive developer is increased by irradiation with actinic rays or radiation. It is a “resin composition that forms a film with reduced solubility”. Therefore, the negative resist composition of the present invention comprises a developer (positive developer) that selectively dissolves and removes an exposed portion having a predetermined threshold value (a) or higher and an exposed portion having a predetermined threshold value (b) or lower. It can be suitably used for pattern formation by multiple development in which a developer (negative developer) to be selectively dissolved / removed and a resist composition for negative development are combined.
That is, as shown in FIG. 3, when a pattern element on an exposure mask is projected onto a wafer by light irradiation, a region having a high light irradiation intensity (an exposed portion having a predetermined threshold value (a) or more) is positively positioned. An optical aerial image (light) is obtained by dissolving / removing with a mold developer and dissolving / removing an area with a low light irradiation intensity (exposed portion below a predetermined threshold (b)) with a negative developer. A pattern having a resolution twice the frequency of the intensity distribution can be obtained.

  In the case of performing a pattern forming process using two types of developers, a positive developer and a negative developer, the order of development is not particularly limited, but after exposure, a positive developer or a negative developer It is preferable to perform development using a negative and positive development using a developer different from the first development. Furthermore, after performing negative development, it is preferable to wash with a negative developing rinse containing an organic solvent. After negative development, it is possible to form a better pattern by washing with a rinse solution containing an organic solvent.

  Hereinafter, a pattern forming method for carrying out the present invention will be described in detail.

<Pattern formation method>
The pattern forming method of the present invention preferably includes the following processes, but is not limited thereto.

(A) A resist composition for negative development, which contains a resin whose polarity is increased by the action of an acid, and which increases its solubility in a positive developer and decreases its solubility in a negative developer by irradiation with actinic rays or radiation. Applying an object and forming a resist film having a receding contact angle with respect to water of 70 degrees or more,
(A) A pattern forming method comprising: a step of exposing through an immersion medium; and (c) a step of developing using a negative developer.

(A ') A resist for negative development that contains a resin whose polarity is increased by the action of an acid, and that increases its solubility in a positive developer and decreases its solubility in a negative developer by irradiation with actinic rays or radiation. Applying the composition;
(I) a pattern forming method comprising: a step of exposing through an immersion medium; and (c) a step of developing using a negative developer, wherein the negative developing resist composition comprises the following components: A pattern forming method comprising:
(A) a resin whose polarity is increased by the action of an acid, the solubility in a positive developer is increased by irradiation with actinic rays or radiation, and the solubility in a negative developer is decreased;
(B) a compound that generates an acid upon irradiation with actinic rays or radiation,
(C) a solvent, and (D) a resin having at least one of a fluorine atom and a silicon atom.

  The pattern forming method of the present invention preferably further includes (e) a step of developing using a positive developer to form a resist pattern. Thereby, a pattern having a resolution twice as high as the frequency of the optical aerial image (light intensity distribution) can be formed.

  (A) A resist composition for negative development, which contains a resin whose polarity is increased by the action of an acid, and which increases its solubility in a positive developer and decreases its solubility in a negative developer by irradiation with actinic rays or radiation. A step of forming a resist film having a receding contact angle with respect to water of 70 degrees or more, or (a ′) a resin whose polarity is increased by the action of an acid, and a positive type by irradiation with actinic rays or radiation The step of applying the negative developing resist composition, which increases the solubility in the developing solution and decreases the solubility in the negative developing solution, can be performed by any method as long as the resist composition can be applied onto the substrate. Well-known spin coating method, spray method, roller coating method, dipping method, etc. can be used, and preferably the resist composition is applied by spin coating method. To. After applying the resist composition, the substrate is heated (pre-baked) as necessary. Thereby, the film | membrane from which the unnecessary residual solvent was removed can be formed uniformly. Although the temperature of prebaking is not specifically limited, 50 to 160 degreeC is preferable, More preferably, it is 60 to 140 degreeC.

In the present invention, the substrate on which the film is formed is not particularly limited, and silicon, SiN, inorganic substrates such as SiO ₂ and SiN, coated inorganic substrates such as SOG, semiconductor manufacturing processes such as IC, liquid crystal, and thermal head For example, a substrate generally used in a circuit board manufacturing process or other photofabrication lithography process can be used.

Before forming the resist film, an antireflection film may be coated on the substrate in advance.
As the antireflection film, any of an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, and amorphous silicon, and an organic film type made of a light absorber and a polymer material can be used. In addition, as an organic antireflection film, ARC series such as DUV30 series manufactured by Brewer Science, DUV-40 series, AR-2, AR-3, AR-5 manufactured by Shipley, ARC29A manufactured by Nissan Chemical Co., etc. Commercially available organic antireflection films can also be used.

In the present invention, a film formed by applying a negative developing resist composition on a substrate has a high receding contact angle with respect to the immersion liquid.
The receding contact angle is the contact angle measured when the contact line at the droplet-substrate interface recedes, and is useful for simulating the ease of droplet movement under dynamic conditions. It is generally known. In simple terms, it can be defined as the contact angle when the droplet interface recedes when the droplet discharged from the needle tip is deposited on the substrate and then sucked into the needle again. It can be measured by using a contact angle measuring method generally called an expansion / contraction method.
In the immersion exposure process, the immersion head needs to move on the wafer following the movement of the exposure head to scan the wafer at high speed to form the exposure pattern. In this case, the contact angle of the immersion liquid with respect to the resist film is important, and the resist is required to follow the high-speed scanning of the exposure head without remaining droplets.
Specifically, the film formed by applying the negative developing resist composition on the substrate in the present invention is, specifically, the receding of the film formed by applying the negative developing resist composition on the substrate with respect to water. The contact angle is preferably 70 degrees or more. By increasing the receding contact angle, a pattern with good LWR can be formed with high throughput following the movement of the lens in immersion exposure. Furthermore, the negative developer can uniformly contact the wafer during development, and scum generation due to development failure can be suppressed.
The receding contact angle of the resist film with respect to water is preferably 70 degrees or more and 100 degrees or less, more preferably 70 degrees or more and 90 degrees or less, and most preferably 75 degrees or more and 90 degrees or less.
In order to form a resist film having a high receding contact angle with respect to the immersion liquid, a “negative-type developing resist composition” described later can be used. Among them, a “negative-type developing” containing resin (D) can be used. It is preferable to use a “resist composition”.
When the negative developing resist composition does not contain the resin (D), the resin (A) in the resist composition may have sufficient hydrophobicity to form a film having a high receding contact angle with respect to the immersion liquid. preferable. Specifically, it is preferable to use a resin that does not contain an alkali-soluble group (such as a carboxylic acid group or a sulfonic acid group) other than a fluorinated alcohol group.

  As the resist composition, (i) a negative developing resist composition containing a resin whose polarity is increased by the action of an acid, increasing the solubility in a positive developer, and decreasing the solubility in a negative developer, ii) A negative developer (preferably an organic developer) is required. Among these, those that can be used for exposure using a wavelength of 250 nm or less are preferable, and those that can be used for exposure using a wavelength of 200 nm or less are more preferable. Examples thereof include the components described later in “Negative developer resist composition”.

(A) In the step of exposing through an immersion medium, the resist film can be exposed by a generally well-known method. Preferably, the resist film is irradiated with actinic rays or radiation through an immersion liquid through a predetermined mask. Although an exposure amount can be set suitably, it is 1-100 mJ / cm < ² > normally.
Although there is no restriction | limiting in particular in the wavelength of the light source used for the exposure apparatus in this invention, It is preferable to use the light of a wavelength of 250 nm or less, More preferably, 200 nm or less, As an example, KrF excimer laser light (248 nm), Examples include ArF excimer laser light (193 nm), F ₂ excimer laser light (157 nm), EUV light (13.5 nm), and electron beams. Among these, it is more preferable to use ArF excimer laser light (193 nm).

When performing an immersion exposure process, (1) after the film is formed on the substrate, before the exposure process and / or (2) after the process of exposing the film via the immersion liquid, the film is heated. Before the step of performing, the step of washing the surface of the membrane with an aqueous chemical solution may be performed.
The immersion liquid (immersion medium) is preferably a liquid that is transparent to the exposure wavelength and has the smallest possible temperature coefficient of refractive index so as to minimize distortion of the optical image projected onto the film. In particular, when the exposure light source is ArF excimer laser light (wavelength: 193 nm), it is preferable to use water from the viewpoints of availability and ease of handling in addition to the above-described viewpoints.
When water is used, an additive (liquid) that decreases the surface tension of water and increases the surface activity may be added in a small proportion. This additive is preferably one that does not dissolve the resist layer on the wafer and can ignore the influence on the optical coating on the lower surface of the lens element. As water to be used, distilled water is preferable. Further, pure water filtered through an ion exchange filter or the like may be used. Thereby, distortion of the optical image projected on the resist due to mixing of impurities can be suppressed.
Further, a medium having a refractive index of 1.5 or more can be used in that the refractive index can be further improved. This medium may be an aqueous solution or an organic solvent.

An immersion liquid poorly soluble film (hereinafter also referred to as “top coat”) may be provided between the resist film and the immersion liquid so that the resist film is not directly brought into contact with the immersion liquid. The necessary functions for the top coat are suitability for application to the upper layer of the resist, radiation, especially transparency to 193 nm, and poor immersion liquid solubility. It is preferable that the top coat is not mixed with the resist and can be uniformly applied to the upper layer of the resist.
From the viewpoint of 193 nm transparency, the topcoat is preferably a polymer that does not contain an aromatic, and specifically, a hydrocarbon polymer, an acrylate polymer, a polymethacrylic acid, a polyacrylic acid, a polyvinyl ether, a silicon-containing polymer, And fluorine-containing polymers.

  When peeling the top coat, a developer may be used, or a separate release agent may be used. As the release agent, a solvent having a small penetration into the resist is preferable. It is preferable that the peeling process can be performed with an alkali developer in that the peeling process can be performed simultaneously with the resist development process. From the viewpoint of peeling with an alkaline developer, the topcoat is preferably acidic, but may be neutral or alkaline from the viewpoint of non-intermixability with the resist.

  The pattern formation method of this invention may have an exposure process in multiple times. The exposure is performed using far ultraviolet light, extreme ultraviolet light, an electron beam, or the like. When performing multiple exposures, the same light source or different light sources may be used. It is preferable to use ArF excimer laser light (wavelength: 193 nm) for the first exposure. It is also possible to have a plurality of exposure steps through the immersion medium.

  After the exposure step, preferably, (i) a heating step (also referred to as baking or PEB (post exposure bake)) is performed, followed by development and rinsing. Thereby, a good pattern can be obtained. The temperature of PEB is not particularly limited as long as a good resist pattern can be obtained, and is usually 40 ° C to 160 ° C. You may have a heating process in multiple times.

  In the present invention, (c) development is carried out using a negative developer to form a resist pattern.

When performing negative development, it is preferable to use an organic developer containing an organic solvent.
As an organic developer that can be used in negative development, polar solvents such as ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents, and hydrocarbon solvents can be used. . For example, 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutylketone, cyclohexanone, methylcyclohexanone, phenylacetone, methylethylketone, methylisobutylketone, acetylacetone , Ketone solvents such as acetonylacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methyl naphthyl ketone, isophorone, propylene carbonate, methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, propylene glycol Monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether Esters such as teracetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate System solvents can be used.
Examples of alcohol solvents include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, n-hexyl alcohol, n-heptyl alcohol, n- Alcohols such as octyl alcohol and n-decanol, glycol solvents such as ethylene glycol, diethylene glycol and triethylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol, propylene glycol, diethylene glycol monomethyl ether, triethylene glycol mono Examples include glycol ether solvents such as ethyl ether and methoxymethylbutanol.
Examples of the ether solvent include dioxane, tetrahydrofuran and the like in addition to the glycol ether solvent.
As the amide solvent, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, hexamethylphosphoric triamide, 1,3-dimethyl-2-imidazolidinone, etc. can be used. .
Examples of the hydrocarbon solvent include aromatic hydrocarbon solvents such as toluene and xylene, and aliphatic hydrocarbon solvents such as pentane, hexane, octane and decane.
A plurality of the above solvents may be mixed, or may be used by mixing with a solvent other than those described above or water.

The vapor pressure of the negative developer is preferably 5 kPa or less, more preferably 3 kPa or less, and most preferably 2 kPa or less at 20 ° C. By setting the vapor pressure of the negative developer to 5 kPa or less, evaporation of the developer on the substrate or in the developing cup is suppressed, and the temperature uniformity in the wafer surface is improved. As a result, the dimensions in the wafer surface are uniform. Sexuality improves.
Specific examples of organic solvents having a vapor pressure of 5 kPa or less at 20 ° C. that can be used as a negative developer include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, 4-heptanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methyl cyclohexanone, ketone solvents such as phenylacetone, methyl isobutyl ketone, butyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol mono Ethyl ether acetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, butyl formate, propyl formate, lactic acid ester , Ester solvents such as butyl lactate, propyl lactate, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, n-hexyl alcohol, n-heptyl alcohol, n -Alcohol solvents such as octyl alcohol and n-decanol, glycol solvents such as ethylene glycol, diethylene glycol and triethylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol, propylene glycol, diethylene glycol monomethyl ether, triethylene Glycol ether solvents such as glycol monoethyl ether and methoxymethylbutanol, ethers such as tetrahydrofuran Solvents, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide amide solvents, toluene, xylene and other aromatic hydrocarbon solvents, octane, decane and other aliphatic hydrocarbons List solvents.
Specific examples of organic solvents having a vapor pressure of 2 kPa or less at 20 ° C. include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, 4-heptanone, 2-hexanone, diisobutylketone, cyclohexanone, methyl Ketone solvents such as cyclohexanone and phenylacetone, butyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 3 -Ethoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, ester solvents such as ethyl lactate, butyl lactate, propyl lactate, n-butyl alcohol, sec-butyl alcohol Alcohol solvents such as coal, tert-butyl alcohol, isobutyl alcohol, n-hexyl alcohol, n-heptyl alcohol, n-octyl alcohol and n-decanol, glycol solvents such as ethylene glycol, diethylene glycol and triethylene glycol, ethylene Glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol, propylene glycol, diethylene glycol monomethyl ether, triethylene glycol monoethyl ether, glycol ether solvents such as methoxymethylbutanol, N-methyl-2-pyrrolidone, N, N-dimethylacetamide N, N-dimethylformamide amide solvents, xylene and other aromatic hydrocarbon solvents, octane, decane and other aliphatic carbonization Motokei solvent, and the like.
Among these, it is preferable to use a negative developer containing an organic solvent selected from ketone solvents, ester solvents and ether solvents, and to use a negative developer containing an organic solvent selected from ester solvents. It is more preferable to use a negative developer containing butyl acetate.

An appropriate amount of a surfactant can be added to the developer that can be used for negative development, if necessary.
The surfactant is not particularly limited, and for example, ionic or nonionic fluorine-based and / or silicon-based surfactants can be used. Examples of these fluorine and / or silicon surfactants include, for example, JP-A No. 62-36663, JP-A No. 61-226746, JP-A No. 61-226745, JP-A No. 62-170950, JP 63-34540 A, JP 7-230165 A, JP 8-62834 A, JP 9-54432 A, JP 9-5988 A, US Pat. No. 5,405,720, etc. The surfactants described in US Pat. Nos. 5,360,692, 5,298,881, 5,296,330, 5,346,098, 5,576,143, 5,294,511, and 5,824,451 can be mentioned. Preferably, it is a nonionic surfactant. Although it does not specifically limit as a nonionic surfactant, It is still more preferable to use a fluorochemical surfactant or a silicon-type surfactant.
The amount of the surfactant used is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and more preferably 0.01 to 0.5% by mass with respect to the total amount of the developer.

As a developing method, for example, a method in which a substrate is immersed in a tank filled with a developer for a certain period of time (dip method), a method in which the developer is raised on the surface of the substrate by surface tension and is left stationary for a certain time (paddle) Method), a method of spraying the developer on the substrate surface (spray method), a method of continuously applying the developer while scanning the developer application nozzle at a constant speed on a substrate rotating at a constant speed (dynamic dispensing method) ) Etc. can be applied.
The step of developing is preferably a step of supplying a negative developer onto the surface of the substrate while rotating the substrate.

  Further, after the step of performing the negative development, a step of stopping the development may be performed while substituting with another solvent.

  After the negative development, it is preferable to include a step of washing with a negative development rinsing solution containing an organic solvent.

  The rinsing liquid used in the rinsing step after negative development is not particularly limited as long as the resist pattern is not dissolved, and a solution containing a general organic solvent can be used. As the rinsing liquid, it is preferable to use a rinsing liquid containing at least one organic solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents and ether solvents. . More preferably, after the negative development, a cleaning step is performed using a rinse solution containing at least one organic solvent selected from a ketone solvent, an ester solvent, an alcohol solvent, and an amide solvent. More preferably, after the negative development, a step of washing with a rinse solution containing an alcohol solvent or an ester solvent is performed. Particularly preferably, after negative development, a step of washing with a rinsing solution containing a monohydric alcohol is performed. Here, examples of the monohydric alcohol used in the rinsing step after the negative development include linear, branched, and cyclic monohydric alcohols. Specifically, 1-butanol, 2-butanol, 3- Methyl-1-butanol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3 -Heptanol, 3-octanol, 4-octanol and the like can be used, and 1-hexanol, 2-hexanol, 1-pentanol and 3-methyl-1-butanol are preferable.

A plurality of these components may be mixed, or may be used by mixing with an organic solvent other than the above.
The step of washing with a rinse solution containing an organic solvent can be performed twice or more using two or more different rinse solutions separately.

  (E) It is preferable that the rinsing solution used in the step of washing with a rinsing solution containing an organic solvent has at least one developer component used in the step of (c) developing with a negative developer. .

  The water content in the rinse liquid is preferably 10% by mass or less, more preferably 5% by mass or less, and particularly preferably 3% by mass or less. By setting the water content to 10% by mass or less, good development characteristics can be obtained.

The vapor pressure of the rinsing solution used after negative development is preferably 0.05 kPa or more and 5 kPa or less at 20 ° C., more preferably 0.1 kPa or more and 5 kPa or less, and most preferably 0.12 kPa or more and 3 kPa or less. By setting the vapor pressure of the rinse liquid to 0.05 kPa or more and 5 kPa or less, the temperature uniformity in the wafer surface is improved, and further, the swelling due to the penetration of the rinse solution is suppressed, and the dimensional uniformity in the wafer surface. Improves.

  An appropriate amount of a surfactant can be added to the rinse solution.

In the rinsing step, the wafer that has been subjected to negative development is cleaned using a rinsing solution containing the organic solvent. The method of the cleaning treatment is not particularly limited. For example, a method of continuously applying the rinse liquid onto the substrate rotating at a constant speed (rotary coating method), or immersing the substrate in a tank filled with the rinse liquid for a certain period of time. A method (dip method), a method of spraying a rinsing liquid onto the substrate surface (spray method), and the like can be applied.
It is preferable that the step of cleaning with the rinse liquid containing the organic solvent is a step of supplying the rinse liquid onto the surface of the substrate while rotating the substrate.
In particular, it is preferable to perform a cleaning process by a spin coating method, rotate the substrate at a rotational speed of 2000 rpm to 4000 rpm after cleaning, and remove the rinse liquid from the substrate.

  In the present invention, it is preferable to further develop (e) a positive developer to form a resist pattern.

As the positive developer, an alkali developer is preferably used. The alkaline developer is preferably a developer containing an aqueous solution containing at least one selected from the group consisting of primary amine compounds, secondary amine compounds, tertiary amine compounds and quaternary amine compounds. In particular, inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, diethylamine, di-n- Secondary amines such as butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, quaternary ammonium such as tetramethylammonium hydroxide and tetraethylammonium hydroxide Salt, pyrrole, piheli It can be used an alkaline aqueous solution of a cyclic amine such as emissions. Among these, it is preferable to use an aqueous solution of tetraethylammonium hydroxide.
Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline developer.
The alkali concentration of the alkali developer (based on the concentration of the amine compound in the developer and the total weight of the developer) is usually from 0.01 to 20% by mass.
The pH of the alkali developer is usually from 10.0 to 15.0.
The time for developing with an alkali developer is usually 10 to 300 seconds.
The alkali concentration (and pH) and development time of the alkali developer can be appropriately adjusted according to the pattern to be formed.

(D) It is preferable to further include (R) a rinsing step after the step of developing using a positive developer.
(F) It is more preferable that the rinsing liquid used in the rinsing step is pure water.
An appropriate amount of a surfactant can be added to the rinse solution.

Further, after the development process or the rinsing process, a process of removing the developer or the rinsing liquid adhering to the pattern with a supercritical fluid can be performed.
Furthermore, after the rinsing process or the process with the supercritical fluid, a heat treatment can be performed to remove moisture remaining in the pattern.

  The negative developing resist composition that can be used in the present invention will be described below.

<Negative development resist composition>
(A) Resin whose polarity is increased by the action of an acid The resin whose polarity is increased by the action of an acid used in the resist composition of the present invention is the main chain or side chain of the resin, or both the main chain and the side chain. And a resin ("acid-decomposable resin", "acid-decomposable resin (A)") or "resin having a group capable of decomposing under the action of an acid to generate an alkali-soluble group (hereinafter also referred to as" acid-decomposable group ") (Also referred to as (A))), having a monocyclic or polycyclic alicyclic hydrocarbon structure, increasing the polarity by the action of an acid, increasing the solubility in an alkali developer, and decreasing the solubility in an organic solvent. It is preferably a resin (hereinafter also referred to as “alicyclic hydrocarbon-based acid-decomposable resin”). The reason is not clear, but it is likely that the positive polarity developer (preferably an alkali developer) and the negative developer (preferably, the polarities of the resin greatly change before and after irradiation with actinic rays or radiation. This is considered to be due to the improvement in dissolution contrast when developed using an organic solvent. Furthermore, a resin having a monocyclic or polycyclic alicyclic hydrocarbon structure has high hydrophobicity, and a negative developing solution (preferably an organic solvent) is used to develop a region of a resist film with low light irradiation intensity. It is considered that the developability of the toner is improved.

  The resist composition of the present invention containing a resin whose polarity is increased by the action of an acid can be suitably used for irradiation with ArF excimer laser light.

Examples of the alkali-soluble group contained in the alicyclic hydrocarbon-based acid-decomposable resin include phenolic hydroxyl group, carboxylic acid group, fluorinated alcohol group, sulfonic acid group, sulfonamide group, sulfonylimide group, (alkylsulfonyl) (alkylcarbonyl) ) Methylene group, (alkylsulfonyl) (alkylcarbonyl) imide group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkyl) And a group having a carbonyl) methylene group or a tris (alkylsulfonyl) methylene group.
Preferred alkali-soluble groups include carboxylic acid groups, fluorinated alcohol groups (preferably hexafluoroisopropanol), and sulfonic acid groups.
A preferred group as an acid-decomposable group (acid-decomposable group) is a group obtained by substituting the hydrogen atom of these alkali-soluble groups with a group capable of leaving with an acid.
Examples of the group leaving with an acid include -C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), -C (R ₃₆ ) (R ₃₇ ) (OR ₃₉ ), -C (R ₀₁ ) (R ₀₂ ). ) (OR ₃₉ ) and the like.
In the formula, R _{36 to} R ₃₉ each independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an alkenyl group. R ₃₆ and R ₃₇ may be bonded to each other to form a ring.
R _{01 and} R ₀₂ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group.
The acid-decomposable group is preferably a cumyl ester group, an enol ester group, an acetal ester group, a tertiary alkyl ester group or the like. More preferably, it is a tertiary alkyl ester group.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention includes a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the following general formula (pI) to general formula (pV) and the following general formula (II- A resin containing at least one selected from the group of repeating units represented by AB) is preferred.

In general formulas (pI) to (pV),
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, and Z is an atom necessary for forming a cycloalkyl group together with a carbon atom. Represents a group.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or cycloalkyl group having 1 to 4 carbon atoms. However, at least one of R _{12 to} R ₁₄ , or any of R ₁₅ and R ₁₆ represents a cycloalkyl group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a cycloalkyl group. However, at least one of R _{17 to} R ₂₁ represents a cycloalkyl group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or cycloalkyl group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a cycloalkyl group. However, at least one of R _{22 to} R ₂₅ represents a cycloalkyl group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

In general formula (II-AB),
R ₁₁ ′ and R ₁₂ ′ each independently represents a hydrogen atom, a cyano group, a halogen atom or an alkyl group.
Z ′ represents an atomic group for forming an alicyclic structure containing two bonded carbon atoms (C—C).

  The general formula (II-AB) is more preferably the following general formula (II-AB1) or general formula (II-AB2).

In the formulas (II-AB1) and (II-AB2),
R ₁₃ ′ to R ₁₆ ′ each independently represents a hydrogen atom, a halogen atom, a cyano group, —COOH, —COOR ₅ , a group that decomposes by the action of an acid, —C (═O) —XA′—R. ₁₇ ′ represents an alkyl group or a cycloalkyl group. At least two of R ₁₃ ′ to R ₁₆ ′ may combine to form a ring.
Here, R ₅ represents an alkyl group, a cycloalkyl group, or a group having a lactone structure.
X represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or an -NHSO ₂ NH-.
A ′ represents a single bond or a divalent linking group.
R ₁₇ ′ represents —COOH, —COOR ₅ , —CN, a hydroxyl group, an alkoxy group, —CO—NH—R ₆ , —CO—NH—SO ₂ —R ₆ or a group having a lactone structure.
R ₆ represents an alkyl group or a cycloalkyl group.
n represents 0 or 1.

In the general formulas (pI) to (pV), the alkyl group in R _{12 to} R ₂₅ represents a linear or branched alkyl group having 1 to 4 carbon atoms.

The cycloalkyl group in R _{11 to} R ₂₅ or the cycloalkyl group formed by Z and the carbon atom may be monocyclic or polycyclic. Specific examples include groups having a monocyclo, bicyclo, tricyclo, tetracyclo structure or the like having 5 or more carbon atoms. The carbon number is preferably 6-30, and particularly preferably 7-25. These cycloalkyl groups may have a substituent.

  Preferred cycloalkyl groups include adamantyl group, noradamantyl group, decalin residue, tricyclodecanyl group, tetracyclododecanyl group, norbornyl group, cedrol group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, A cyclodecanyl group and a cyclododecanyl group can be mentioned. More preferable examples include an adamantyl group, norbornyl group, cyclohexyl group, cyclopentyl group, tetracyclododecanyl group, and tricyclodecanyl group.

  As further substituents of these alkyl groups and cycloalkyl groups, alkyl groups (1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (1 to 4 carbon atoms), carboxyl groups, alkoxycarbonyl groups (carbon numbers) 2-6). Examples of the substituent that the alkyl group, alkoxy group, alkoxycarbonyl group and the like may further have include a hydroxyl group, a halogen atom, and an alkoxy group.

  The structures represented by the general formulas (pI) to (pV) in the resin can be used for protecting alkali-soluble groups. Examples of the alkali-soluble group include various groups known in this technical field.

  Specific examples include a structure in which a hydrogen atom of a carboxylic acid group, a sulfonic acid group, a phenol group, or a thiol group is substituted with a structure represented by the general formulas (pI) to (pV), preferably a carboxylic acid Group, a hydrogen atom of a sulfonic acid group is substituted with a structure represented by general formulas (pI) to (pV).

  As the repeating unit having an alkali-soluble group protected by the structure represented by the general formulas (pI) to (pV), a repeating unit represented by the following general formula (pA) is preferable.

Here, R represents a hydrogen atom, a halogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms. A plurality of R may be the same or different.
A represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, or a urea group, or a combination of two or more groups. Represents. A single bond is preferable.
Rp ₁ represents any group of the above formulas (pI) to (pV).

  The repeating unit represented by the general formula (pA) is particularly preferably a repeating unit composed of 2-alkyl-2-adamantyl (meth) acrylate and dialkyl (1-adamantyl) methyl (meth) acrylate.

  Hereinafter, although the specific example of the repeating unit shown by general formula (pA) is shown, this invention is not limited to this.

Examples of the halogen atom in the general formula (II-AB), R ₁₁ ′, and R ₁₂ ′ include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

Examples of the alkyl group in R ₁₁ ′ and R ₁₂ ′ include a linear or branched alkyl group having 1 to 10 carbon atoms.

  The atomic group for forming the alicyclic structure of Z ′ is an atomic group that forms a repeating unit of an alicyclic hydrocarbon which may have a substituent in a resin, and among them, a bridged type alicyclic group. An atomic group for forming a bridged alicyclic structure forming a cyclic hydrocarbon repeating unit is preferred.

Examples of the skeleton of the alicyclic hydrocarbon formed include the same alicyclic hydrocarbon groups as R _{12 to} R _{25 in} the general formulas (pI) to (pV).

The alicyclic hydrocarbon skeleton may have a substituent. Examples of such a substituent include R ₁₃ ′ to R ₁₆ ′ in the general formula (II-AB1) or (II-AB2).

  In the alicyclic hydrocarbon-based acid-decomposable resin according to the present invention, the group decomposed by the action of an acid has a partial structure containing the alicyclic hydrocarbon represented by the general formula (pI) to the general formula (pV). It can be contained in at least one kind of repeating unit among the repeating unit having, the repeating unit represented by formula (II-AB), and the repeating unit of the copolymerization component described later. The group capable of decomposing by the action of an acid is preferably contained in a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by general formula (pI) to general formula (pV).

Various substituents of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-AB1) or the general formula (II-AB2) are atomic groups for forming an alicyclic structure in the general formula (II-AB). It can also be a substituent of the atomic group Z ′ for forming a bridged alicyclic structure.

  Specific examples of the repeating unit represented by the general formula (II-AB1) or (II-AB2) include the following specific examples, but the present invention is not limited to these specific examples.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention preferably has a lactone group. As the lactone group, any group can be used as long as it contains a lactone structure, but it is preferably a group containing a 5- to 7-membered ring lactone structure, and a bicyclo structure in the 5- to 7-membered ring lactone structure, Those in which other ring structures are condensed to form a spiro structure are preferred. It is more preferable to have a repeating unit having a group having a lactone structure represented by any of the following general formulas (LC1-1) to (LC1-16). Further, a group having a lactone structure may be directly bonded to the main chain. Preferred lactone structures are groups represented by general formulas (LC1-1), (LC1-4), (LC1-5), (LC1-6), (LC1-13), (LC1-14), By using a specific lactone structure, line edge roughness and development defects are improved.

The lactone structure moiety may or may not have a substituent (Rb ₂ ). Preferred substituents (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 1 to 8 carbon atoms, and a carboxyl group. , Halogen atom, hydroxyl group, cyano group, acid-decomposable group and the like. n2 represents an integer of 0 to 4. When n2 is 2 or more, a plurality of Rb ₂ may be the same or different, and a plurality of Rb ₂ may be bonded to form a ring.

As the repeating unit having a group having a lactone structure represented by any of the general formulas (LC1-1) to (LC1-16), R _{13 in the} above general formula (II-AB1) or (II-AB2) may be used. Wherein at least one of 'to R ₁₆ ' has a group represented by the general formulas (LC1-1) to (LC1-16) (for example, R _{5 of} -COOR ₅ is represented by the general formulas (LC1-1) to (LC1) -16) or a repeating unit represented by the following general formula (AI).

In general formula (AI),
R _b0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.
Preferable substituents that the alkyl group for R _b0 may have include a hydroxyl group and a halogen atom.
Examples of the halogen atom for R _b0 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
R _b0 is preferably a hydrogen atom or a methyl group.
A _b represents a single bond, an alkylene group, a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, or a divalent group obtained by combining these. A linking group represented by a single bond or —Ab ₁ —CO ₂ — is preferable. Ab ₁ is a linear, branched alkylene group, monocyclic or polycyclic cycloalkylene group, preferably a methylene group, an ethylene group, a cyclohexylene group, an adamantylene group or a norbornylene group.
V represents a group represented by any one of the general formulas (LC1-1) to (LC1-16).

  The repeating unit having a lactone structure usually has an optical isomer, but any optical isomer may be used. One optical isomer may be used alone, or a plurality of optical isomers may be mixed and used. When one kind of optical isomer is mainly used, the optical purity (ee) thereof is preferably 90 or more, more preferably 95 or more.

  Specific examples of the repeating unit having a group having a lactone structure are given below, but the present invention is not limited thereto.

The alicyclic hydrocarbon-based acid-decomposable resin of the present invention has a repeating unit containing an organic group having a polar group, particularly a repeating unit having an alicyclic hydrocarbon structure substituted with a polar group. preferable. This improves the substrate adhesion and developer compatibility. The alicyclic hydrocarbon structure of the alicyclic hydrocarbon structure substituted with a polar group is preferably an adamantyl group, a diamantyl group, or a norbornane group. The polar group is preferably a hydroxyl group or a cyano group.
As the alicyclic hydrocarbon structure substituted with a polar group, partial structures represented by the following general formulas (VIIa) to (VIId) are preferable.

In general formulas (VIIa) to (VIIc),
R _{2c to} R _4c each independently represents a hydrogen atom, a hydroxyl group or a cyano group. However, at least one of R _{2c to} R _4c represents a hydroxyl group or a cyano group. Preferably, one or two of R _{2c to} R _4c are a hydroxyl group and the rest are hydrogen atoms.
In general formula (VIIa), it is more preferable that two members out of R _{2c to} R _4c are a hydroxyl group and the remaining is a hydrogen atom.

As the repeating unit having a group represented by the general formulas (VIIa) to (VIId), at least one of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-AB1) or (II-AB2) is the above. has a group represented by the general formula (VII) (e.g., represents a group R ₅ in -COOR ₅ is a represented by the general formula (VIIa) ~ (VIId)) , or the following general formula (AIIa) ~ ( A repeating unit represented by AId) can be mentioned.

In general formulas (AIIa) to (AIId),
R _1c represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.
R _2c to R _4c have the same meanings as R _2c to R _4c in formulas (VIIa) ~ (VIIc).

  Although the specific example of the repeating unit which has a structure represented by general formula (AIIa)-(AIId) is given to the following, this invention is not limited to these.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention may have a repeating unit represented by the following general formula (VIII).

In the above general formula (VIII),
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 . R ₄₂ represents an alkyl group, a cycloalkyl group or a camphor residue. The alkyl group of R ₄₁ and R ₄₂ may be substituted with a halogen atom (preferably a fluorine atom) or the like.

  Examples of the repeating unit represented by the general formula (VIII) include the following specific examples, but the present invention is not limited thereto.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention preferably has a repeating unit having an alkali-soluble group, and more preferably has a repeating unit having a carboxyl group. By containing this, the resolution in contact hole applications increases. The repeating unit having a carboxyl group includes a repeating unit in which a carboxyl group is directly bonded to the main chain of the resin, such as a repeating unit of acrylic acid or methacrylic acid, or a carboxyl group in the main chain of the resin through a linking group. Either a repeating unit that is bonded, or a polymerization initiator or chain transfer agent having an alkali-soluble group is introduced at the end of the polymer chain during polymerization, and the linking group is a monocyclic or polycyclic hydrocarbon. You may have a structure. Particularly preferred are repeating units of acrylic acid or methacrylic acid.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention may further have a repeating unit having 1 to 3 groups represented by the general formula (F1). This improves line edge roughness performance.

In general formula (F1),
R _{50 to} R ₅₅ each independently represents a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _{50 to} R ₅₅ represents a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom.
Rx represents a hydrogen atom or an organic group (preferably an acid-decomposable protecting group, an alkyl group, a cycloalkyl group, an acyl group, or an alkoxycarbonyl group).

The alkyl group of R _{50 to} R ₅₅ may be substituted with a halogen atom such as a fluorine atom, a cyano group, etc., preferably an alkyl group having 1 to 3 carbon atoms, such as a methyl group or a trifluoromethyl group. be able to.
R _{50 to} R ₅₅ are preferably all fluorine atoms.

  Examples of the organic group represented by Rx include an acid-decomposable protective group and an optionally substituted alkyl group, cycloalkyl group, acyl group, alkylcarbonyl group, alkoxycarbonyl group, alkoxycarbonylmethyl group, alkoxymethyl group. , 1-alkoxyethyl group is preferable.

  The repeating unit having a group represented by the general formula (F1) is preferably a repeating unit represented by the following general formula (F2).

In general formula (F2),
Rx represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. Preferable substituents that the alkyl group of Rx may have include a hydroxyl group and a halogen atom.
Fa represents a single bond or a linear or branched alkylene group (preferably a single bond).
Fb represents a monocyclic or polycyclic hydrocarbon group.
Fc represents a single bond or a linear or branched alkylene group (preferably a single bond or a methylene group).
F ₁ represents a group represented by the general formula (F1).
P ₁ represents a 1 to 3.
The cyclic hydrocarbon group in Fb is preferably a cyclopentylene group, a cyclohexylene group, or a norbornylene group.

  Specific examples of the repeating unit having a group represented by the general formula (F1) are shown below, but the present invention is not limited thereto.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention may further contain a repeating unit having an alicyclic hydrocarbon structure and not exhibiting acid decomposability. This can reduce the elution of low molecular components from the resist film to the immersion liquid during immersion exposure. Examples of such a repeating unit include 1-adamantyl (meth) acrylate, tricyclodecanyl (meth) acrylate, and cyclohexyl (meth) acrylate.

  In addition to the above repeating structural units, the alicyclic hydrocarbon-based acid-decomposable resin of the present invention has a dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and resolving power that is a general necessary characteristic of resist. Various repeating structural units can be contained for the purpose of adjusting heat resistance, sensitivity, and the like.

  Examples of such repeating structural units include, but are not limited to, repeating structural units corresponding to the following monomers.

  As a result, the performance required for the alicyclic hydrocarbon-based acid-decomposable resin, in particular, (1) solubility in coating solvents, (2) film-forming properties (glass transition temperature), (3) positive developer and negative Fine adjustments such as solubility in a mold developer, (4) film sliding (selection of hydrophilicity / hydrophobicity, alkali-soluble group), (5) adhesion of unexposed part to substrate, (6) dry etching resistance, etc. .

  As such a monomer, for example, a compound having one addition polymerizable unsaturated bond selected from acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, etc. Etc.

  In addition, any addition-polymerizable unsaturated compound that can be copolymerized with monomers corresponding to the above various repeating structural units may be copolymerized.

  In alicyclic hydrocarbon-based acid-decomposable resins, the molar ratio of each repeating structural unit is the resist dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and resolution that is the general required performance of resists. In order to adjust heat resistance, sensitivity, etc., it is set appropriately.

Preferred embodiments of the alicyclic hydrocarbon-based acid-decomposable resin of the present invention include the following.
(1) What contains the repeating unit which has a partial structure containing the alicyclic hydrocarbon represented by said general formula (pI)-(pV) (side chain type).
Preferably those containing (meth) acrylate repeating units having a structure of (pI) to (pV).
(2) One containing a repeating unit represented by the general formula (II-AB) (main chain type).
However, in (2), for example, the following can be further mentioned.
(3) A repeating unit represented by the general formula (II-AB), a maleic anhydride derivative and a (meth) acrylate structure (hybrid type).

  In the alicyclic hydrocarbon-based acid-decomposable resin, the content of the repeating unit having an acid-decomposable group is preferably 10 to 60 mol%, more preferably 20 to 50 mol%, still more preferably 25 in all repeating structural units. -40 mol%.

  In the acid-decomposable resin, the content of the repeating unit having an acid-decomposable group is preferably 10 to 60 mol%, more preferably 20 to 50 mol%, still more preferably 25 to 40 mol% in all repeating structural units. is there.

  In the alicyclic hydrocarbon-based acid-decomposable resin, the content of the repeating unit having a partial structure containing the alicyclic hydrocarbon represented by the general formulas (pI) to (pV) is 20 to 70 in all the repeating structural units. The mol% is preferable, more preferably 20 to 50 mol%, still more preferably 25 to 40 mol%.

  In the alicyclic hydrocarbon-based acid-decomposable resin, the content of the repeating unit represented by the general formula (II-AB) is preferably 10 to 60 mol%, more preferably 15 to 55 mol% in all repeating structural units. More preferably, it is 20-50 mol%.

In the acid-decomposable resin, the content of the repeating unit having a lactone ring is preferably 10 to 70 mol%, more preferably 20 to 60 mol%, still more preferably 25 to 40 mol% in all repeating structural units.
In the acid-decomposable resin, the content of the repeating unit having an organic group having a polar group is preferably 1 to 40 mol%, more preferably 5 to 30 mol%, still more preferably 5 to 20 mol in all repeating structural units. %.

  In addition, the content of the repeating structural unit based on the monomer of the further copolymer component in the resin can also be appropriately set according to the performance of the desired resist. ) To 99 p% with respect to the total number of moles of the repeating structural unit having a partial structure containing an alicyclic hydrocarbon represented by (pV) and the repeating unit represented by the general formula (II-AB). The following is preferable, More preferably, it is 90 mol% or less, More preferably, it is 80 mol% or less.

  When the negative developing resist composition of the present invention is for ArF exposure, the resin preferably has no aromatic group from the viewpoint of transparency to ArF light.

  The alicyclic hydrocarbon-based acid-decomposable resin used in the present invention is preferably one in which all of the repeating units are composed of (meth) acrylate-based repeating units. In this case, all of the repeating units may be methacrylate repeating units, all of the repeating units may be acrylate repeating units, and all of the repeating units may be any mixture of methacrylate repeating units / acrylate repeating units, It is preferable that the acrylate repeating unit is 50 mol% or less of the entire repeating unit.

  The alicyclic hydrocarbon-based acid-decomposable resin includes at least a (meth) acrylate-based repeating unit having a lactone ring, a (meth) acrylate-based repeating unit having an organic group substituted with at least one of a hydroxyl group and a cyano group, and A copolymer having three types of repeating units of a (meth) acrylate-based repeating unit having an acid-decomposable group is preferable.

  Preferably, 20 to 50 mol% of repeating units having a partial structure containing an alicyclic hydrocarbon represented by general formulas (pI) to (pV), 20 to 50 mol% of repeating units having a lactone structure, substituted with a polar group It is a ternary copolymer containing 5 to 30% of repeating units having an alicyclic hydrocarbon structure, or a quaternary copolymer containing 0 to 20% of other repeating units.

  Particularly preferable resins include 20 to 50 mol% of repeating units having an acid-decomposable group represented by the following general formulas (ARA-1) to (ARA-7), and the following general formulas (ARL-1) to (ARL- 7) Repeating unit having an alicyclic hydrocarbon structure substituted with a polar group represented by the following general formulas (ARH-1) to (ARH-3): 20-50 mol% having a lactone group represented by 7) A ternary copolymer containing 5 to 30 mol% of units, or a carboxyl group, or a repeating unit having a structure represented by the general formula (F1), or an alicyclic hydrocarbon structure and not exhibiting acid decomposability. It is a quaternary copolymer containing 5 to 20 mol% of repeating units.

(In the formula, Rxy ₁ represents a hydrogen atom or a methyl group, Rxa ₁ and Rxb ₁ each independently represent a methyl group or an ethyl group, and Rxc ₁ represents a hydrogen atom or a methyl group.)

(In the formula, Rxy ₁ represents a hydrogen atom or a methyl group, Rxd ₁ represents a hydrogen atom or a methyl group, and Rxe ₁ represents a trifluoromethyl group, a hydroxyl group, or a cyano group.)

(In the formula, Rxy ₁ represents a hydrogen atom or a methyl group.)

  The alicyclic hydrocarbon-based acid-decomposable resin used in the present invention can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, a monomer polymerization method in which a monomer species and an initiator are dissolved in a solvent and heating is performed, and a solution of the monomer species and the initiator is dropped into the heating solvent over 1 to 10 hours. The dropping polymerization method is added, and the dropping polymerization method is preferable. Examples of the reaction solvent include ethers such as tetrahydrofuran, 1,4-dioxane and diisopropyl ether, ketones such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate, amide solvents such as dimethylformamide and dimethylacetamide, Furthermore, the solvent which melt | dissolves the composition of this invention like the below-mentioned propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and cyclohexanone is mentioned. More preferably, the polymerization is performed using the same solvent as that used in the resist composition of the present invention. Thereby, generation | occurrence | production of the particle at the time of a preservation | save can be suppressed.

The polymerization reaction is preferably performed in an inert gas atmosphere such as nitrogen or argon. As a polymerization initiator, a commercially available radical initiator (azo initiator, peroxide, etc.) is used to initiate the polymerization. As the radical initiator, an azo initiator is preferable, and an azo initiator having an ester group, a cyano group, or a carboxyl group is preferable. Preferred examples of the initiator include azobisisobutyronitrile, azobisdimethylvaleronitrile, dimethyl 2,2′-azobis (2-methylpropionate) and the like. If desired, an initiator is added or added in portions, and after completion of the reaction, it is put into a solvent and a desired polymer is recovered by a method such as powder or solid recovery. The concentration of the reaction is 5 to 50% by mass, preferably 10 to 30% by mass. The reaction temperature is usually from 10 ° C to 150 ° C, preferably from 30 ° C to 120 ° C, more preferably from 60 ° C to 100 ° C.
For purification, the same method as that for the resin (D) described later can be used, and a liquid-liquid extraction method that removes residual monomers and oligomer components by combining water washing and an appropriate solvent, only those having a specific molecular weight or less. A purification method in a solution state such as ultrafiltration to extract and remove the residual monomer by coagulating the resin in the poor solvent by dropping the resin solution into the poor solvent, A usual method such as a purification method in a solid state, such as washing the filtered resin slurry with a poor solvent, can be applied.

The weight average molecular weight of the resin according to the present invention is preferably 1,000 to 200,000, more preferably 1,000 to 20,000, and most preferably 1,000 to 15 in terms of polystyrene by GPC method. , 000. By setting the weight average molecular weight to 1,000 to 200,000, deterioration of heat resistance and dry etching resistance can be prevented, and developability is deteriorated, and viscosity is increased, resulting in deterioration of film forming property. Can be prevented.
The degree of dispersion (molecular weight distribution) is usually 1 to 5, preferably 1 to 3, more preferably 1.2 to 3.0, particularly preferably 1.2 to 2.0. . The smaller the degree of dispersion, the better the resolution and the resist shape, the smoother the side wall of the resist pattern, and the better the roughness.

In the resist composition of the present invention, the blending amount of all the resins according to the present invention in the entire composition is preferably 50 to 99.9% by mass, more preferably 60 to 99.0% by mass in the total solid content. is there.
In the present invention, the resins may be used alone or in combination.

  When the negative developing resist composition of the present invention contains a resin (D) described later, the alicyclic hydrocarbon-based acid-decomposable resin (A) is a fluorine atom from the viewpoint of compatibility with the resin (D). And it is preferable not to contain a silicon atom.

(B) Compound that generates acid upon irradiation with actinic ray or radiation The resist composition of the present invention is a compound that generates acid upon irradiation with actinic ray or radiation (also referred to as “photoacid generator” or “(B) component”). ).
Examples of such photoacid generators include photoinitiators for photocationic polymerization, photoinitiators for photoradical polymerization, photodecolorants for dyes, photochromic agents, actinic rays used in microresists, etc. Known compounds that generate an acid upon irradiation with radiation and mixtures thereof can be appropriately selected and used.

  Examples thereof include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.

  Further, a group that generates an acid upon irradiation with these actinic rays or radiation, or a compound in which a compound is introduced into the main chain or side chain of the polymer, for example, US Pat. No. 3,849,137, German Patent No. 3914407. JP, 63-26653, JP, 55-164824, JP, 62-69263, JP, 63-146038, JP, 63-163452, JP, 62-153853, The compounds described in JP-A 63-146029 can be used.

  Furthermore, compounds capable of generating an acid by light described in US Pat. No. 3,779,778, European Patent 126,712 and the like can also be used.

  Among the compounds that decompose upon irradiation with actinic rays or radiation to generate an acid, compounds represented by the following general formulas (ZI), (ZII), and (ZIII) can be exemplified.

In the above general formula (ZI), R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
X ⁻ represents a non-nucleophilic anion, preferably sulfonate anion, carboxylate anion, bis (alkylsulfonyl) amide anion, tris (alkylsulfonyl) methide anion, BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ^{− and the} like. Preferably, it is an organic anion containing a carbon atom.

  Preferable organic anions include organic anions represented by the following formula.

Where
Rc ₁ represents an organic group.
Examples of the organic group in Rc ₁ include those having 1 to 30 carbon atoms, and preferably an alkyl group, an aryl group, or a plurality thereof, which may be substituted, is a single bond, —O—, —CO ₂ —, — Examples include groups linked by a linking group such as S-, -SO _3- , -SO ₂ N (Rd ₁ )-. Rd ₁ represents a hydrogen atom or an alkyl group.
Rc ₃ , Rc ₄ and Rc ₅ each independently represents an organic group. Preferred examples of the organic group for Rc ₃ , Rc ₄ , and Rc ₅ include the same organic groups as those for Rc ₁ , and most preferred is a C 1-4 perfluoroalkyl group.
Rc ₃ and Rc ₄ may combine to form a ring. Examples of the group formed by combining Rc ₃ and Rc ₄ include an alkylene group and an arylene group. Preferably, it is a C2-C4 perfluoroalkylene group.
The organic group of Rc ₁ and Rc _{3 to} Rc ₅ is particularly preferably an alkyl group substituted at the 1-position with a fluorine atom or a fluoroalkyl group, or a phenyl group substituted with a fluorine atom or a fluoroalkyl group. By having a fluorine atom or a fluoroalkyl group, the acidity of the acid generated by light irradiation is increased and the sensitivity is improved. Further, when Rc ₃ and Rc ₄ are combined to form a ring, the acidity of the acid generated by light irradiation is increased, and the sensitivity is improved.

The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).
Specific examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include corresponding groups in the compounds (ZI-1), (ZI-2) and (ZI-3) described later.

In addition, the compound which has two or more structures represented by general formula (ZI) may be sufficient. For example, the general formula at least one of R ₂₀₁ to R ₂₀₃ of a compound represented by (ZI) is, at least one bond with structure of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (ZI) It may be a compound.

  More preferable (ZI) components include compounds (ZI-1), (ZI-2), and (ZI-3) described below.

The compound (ZI-1) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (ZI), arylsulfonium compound, i.e., a compound having arylsulfonium as a cation.
In the arylsulfonium compound, all of R _{201 to} R ₂₀₃ may be an aryl group, or a part of R _{201 to} R ₂₀₃ may be an aryl group, and the rest may be an alkyl group or a cycloalkyl group.
Examples of the arylsulfonium compound include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, diarylcycloalkylsulfonium compounds, and aryldicycloalkylsulfonium compounds.
The aryl group of the arylsulfonium compound is preferably an aryl group such as a phenyl group or a naphthyl group, or a heteroaryl group such as an indole residue or a pyrrole residue, more preferably a phenyl group or an indole residue. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.
The alkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, sec- Examples thereof include a butyl group and a t-butyl group.
The cycloalkyl group that the arylsulfonium compound has as necessary is preferably a cycloalkyl group having 3 to 15 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.
Aryl group, alkyl group of R ₂₀₁ to R _203, cycloalkyl group, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms) , An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group may be substituted. Preferred substituents are linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, and particularly preferable. Is an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

Next, the compound (ZI-2) will be described. Compound (ZI-2) is a compound in the case where R _{201 to} R ₂₀₃ in formula (ZI) each independently represents an organic group containing no aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.
The organic group having no aromatic ring as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.
R _{201 to} R ₂₀₃ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear, branched, cyclic 2-oxoalkyl group, or an alkoxycarbonylmethyl group, particularly preferably Is a linear, branched 2-oxoalkyl group.

The alkyl group as R ₂₀₁ to R ₂₀₃ may be linear, it may be either branched, preferably a straight-chain or branched alkyl group (e.g., methyl group having 1 to 10 carbon atoms, an ethyl group, a propyl Group, butyl group, pentyl group). The alkyl group as R ₂₀₁ to R ₂₀₃ is a straight-chain or branched 2-oxoalkyl group is preferably an alkoxycarbonyl methyl group.
The cycloalkyl group as R ₂₀₁ to R ₂₀₃ is preferably, and a cycloalkyl group having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, norbornyl). The cycloalkyl group as R ₂₀₁ to R ₂₀₃ is preferably a cyclic 2-oxoalkyl group.
Linear as R ₂₀₁ to R _203, branched or cyclic 2-oxoalkyl group may preferably be a group having a 2-position> C = O in the above-described alkyl or cycloalkyl group.
The alkoxy group in the alkoxycarbonylmethyl group as R ₂₀₁ to R _203, preferably may be mentioned alkoxy groups having 1 to 5 carbon atoms (a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group).
R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

  The compound (ZI-3) is a compound represented by the following general formula (ZI-3), and is a compound having a phenacylsulfonium salt structure.

In general formula (ZI-3),
R _{1c to} R _5c each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, or a halogen atom.
R _6c and R _7c each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group.
Rx and Ry each independently represents an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group.
Any two or more of R _1c to R _7c, and R _x and R _y may be bonded to each other to form a ring structure, the ring structure may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond May be included. Examples of the group formed by combining any two or more of R _{1c to} R _7c and R _x and R _y include a butylene group and a pentylene group.
X ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as X ^{− in} formula (ZI).

The alkyl group as R _{1c to} R _7c may be either linear or branched, for example, a linear or branched alkyl group having 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms. Or a linear or branched alkyl group (for example, a methyl group, an ethyl group, a linear or branched propyl group, a linear or branched butyl group, or a linear or branched pentyl group).
The cycloalkyl group as R _{1c to} R _7c is preferably a cycloalkyl group having 3 to 8 carbon atoms (for example, a cyclopentyl group or a cyclohexyl group).
The alkoxy group as R _{1c to} R _{5c may} be linear, branched or cyclic, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group), C3-C8 cyclic alkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group) ).
Preferably, any one of R _{1c to} R _5c is a linear or branched alkyl group, a cycloalkyl group, or a linear, branched or cyclic alkoxy group, and more preferably the sum of the carbon number of R _{1c to} R _5c is 2 ~ 15. Thereby, solvent solubility improves more and generation | occurrence | production of a particle is suppressed at the time of a preservation | save.

_Examples of the alkyl group as R _x and R _y include the same alkyl groups as R _{1c to} R _7c . The alkyl group as R _x and R _y is preferably a linear or branched 2-oxoalkyl group or an alkoxycarbonylmethyl group.
The cycloalkyl group as R _x and R _y may be the same as the cycloalkyl group as R _1c to R _7c. The cycloalkyl group as R _x and R _y is preferably a cyclic 2-oxoalkyl group.
Examples of the linear, branched, or cyclic 2-oxoalkyl group include a group having> C═O at the 2-position of the alkyl group or cycloalkyl group as R _{1c to} R _7c .
Examples of the alkoxy group in the alkoxycarbonylmethyl group include the same alkoxy groups as R _{1c to} R _5c .
R _x and R _y are preferably an alkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more.

In general formulas (ZII) and (ZIII),
R ₂₀₄ to R ₂₀₇ each independently represents an aryl group, an alkyl group or a cycloalkyl group.
Phenyl group and a naphthyl group are preferred as the aryl group of R ₂₀₄ to R _207, more preferably a phenyl group.
The alkyl group as R ₂₀₄ to R ₂₀₇ may be linear, it may be either branched, preferably a straight-chain or branched alkyl group (e.g., methyl group having 1 to 10 carbon atoms, an ethyl group, a propyl Group, butyl group, pentyl group).
The cycloalkyl group as R ₂₀₄ to R ₂₀₇ is preferably, and a cycloalkyl group having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, norbornyl).
R ₂₀₄ to R ₂₀₇ may have a substituent. The R ₂₀₄ to R ₂₀₇ are substituents which may have, for example, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (e.g., 6 carbon atoms 15), alkoxy groups (for example, having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups and the like.
X ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as X ^{− in} formula (ZI).

  Among the compounds that generate an acid upon irradiation with actinic rays or radiation, compounds represented by the following general formulas (ZIV), (ZV), and (ZVI) can be further exemplified.

In general formulas (ZIV) to (ZVI),
Ar ₃ and Ar ₄ each independently represents an aryl group.
R ₂₂₆ represents an alkyl group or an aryl group.
R ₂₂₇ and R ₂₂₈ each independently represents an alkyl group, an aryl group, or an electron-withdrawing group. R ₂₂₇ is preferably an aryl group.
R ₂₂₈ is preferably an electron-withdrawing group, more preferably a cyano group or a fluoroalkyl group.
A represents an alkylene group, an alkenylene group or an arylene group.

  As the compound that generates an acid upon irradiation with actinic rays or radiation, compounds represented by general formulas (ZI) to (ZIII) are preferable.

  The compound (B) is preferably a compound that generates an aliphatic sulfonic acid having a fluorine atom or a benzenesulfonic acid having a fluorine atom upon irradiation with actinic rays or radiation.

  The compound (B) preferably has a triphenylsulfonium structure.

  The compound (B) is preferably a triphenylsulfonium salt compound having an alkyl group or a cycloalkyl group not substituted with fluorine in the cation moiety.

  Among the compounds that generate an acid upon irradiation with actinic rays or radiation, examples of particularly preferable compounds are listed below.

A photo-acid generator can be used individually by 1 type or in combination of 2 or more types. When two or more types are used in combination, it is preferable to combine two types of compounds that generate two types of organic acids that differ in the total number of atoms excluding hydrogen atoms by two or more.
The content of the photoacid generator is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, and further preferably 1 to 7% by mass, based on the total solid content of the resist composition. . By setting the content of the photoacid generator within this range, the exposure latitude when the resist pattern is formed and the crosslinking reactivity with the crosslinked layer forming material are improved.

(C) Solvent Solvents that can be used when preparing the resist composition by dissolving the above components include, for example, alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, lactate alkyl ester, and alkoxypropion. Examples thereof include organic solvents such as alkyl acid, cyclic lactones having 4 to 10 carbon atoms, monoketone compounds having 4 to 10 carbon atoms which may contain a ring, alkylene carbonate, alkyl alkoxyacetate, and alkyl pyruvate.

Examples of the alkylene glycol monoalkyl ether carboxylate include propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, propylene glycol monomethyl ether propionate, propylene glycol monoethyl Preferred examples include ether propionate, ethylene glycol monomethyl ether acetate, and ethylene glycol monoethyl ether acetate.
Preferred examples of the alkylene glycol monoalkyl ether include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether.

Preferred examples of the alkyl lactate include methyl lactate, ethyl lactate, propyl lactate and butyl lactate.
Preferable examples of the alkyl alkoxypropionate include ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, and ethyl 3-methoxypropionate.

  Examples of the cyclic lactone having 4 to 10 carbon atoms include β-propiolactone, β-butyrolactone, γ-butyrolactone, α-methyl-γ-butyrolactone, β-methyl-γ-butyrolactone, γ-valerolactone, γ- Caprolactone, γ-octanoic lactone, and α-hydroxy-γ-butyrolactone are preferred.

  Examples of the monoketone compound having 4 to 10 carbon atoms which may contain a ring include 2-butanone, 3-methylbutanone, pinacolone, 2-pentanone, 3-pentanone, 3-methyl-2-pentanone, 4- Methyl-2-pentanone, 2-methyl-3-pentanone, 4,4-dimethyl-2-pentanone, 2,4-dimethyl-3-pentanone, 2,2,4,4-tetramethyl-3-pentanone, 2 -Hexanone, 3-hexanone, 5-methyl-3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, 2,6-dimethyl-4 -Heptanone, 2-octanone, 3-octanone, 2-nonanone, 3-nonanone, 5-nonanone, 2-decanone, 3-decanone, 4-decanone, 5- Xen-2-one, 3-penten-2-one, cyclopentanone, 2-methylcyclopentanone, 3-methylcyclopentanone, 2,2-dimethylcyclopentanone, 2,4,4-trimethylcyclopenta Non, cyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, 4-ethylcyclohexanone, 2,2-dimethylcyclohexanone, 2,6-dimethylcyclohexanone, 2,2,6-trimethylcyclohexanone, cycloheptanone, 2-methylcyclo Preferred are heptanone and 3-methylcycloheptanone.

Preferred examples of the alkylene carbonate include propylene carbonate, vinylene carbonate, ethylene carbonate, and butylene carbonate.
Examples of the alkyl alkoxyacetate include 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 2- (2-ethoxyethoxy) ethyl acetate, 3-methoxy-3-methylbutyl acetate, and 1-methoxy-acetate. 2-propyl is preferred.
Preferred examples of the alkyl pyruvate include methyl pyruvate, ethyl pyruvate, and propyl pyruvate.
As a solvent which can be preferably used, a solvent having a boiling point of 130 ° C. or higher under normal temperature and normal pressure can be mentioned. Specifically, cyclopentanone, γ-butyrolactone, cyclohexanone, ethyl lactate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, ethyl 3-ethoxypropionate, ethyl pyruvate, 2-ethoxyethyl acetate, acetic acid -2- (2-ethoxyethoxy) ethyl and propylene carbonate are mentioned.
In the present invention, the above solvents may be used alone or in combination of two or more.

In this invention, you may use the mixed solvent which mixed the solvent which contains a hydroxyl group in a structure, and the solvent which does not contain a hydroxyl group as an organic solvent.
Examples of the solvent containing a hydroxyl group include ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethyl lactate, and the like. Particularly preferred are propylene glycol monomethyl ether and ethyl lactate.
Examples of the solvent not containing a hydroxyl group include propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, butyl acetate, N-methylpyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide and the like. Among these, propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, and butyl acetate are particularly preferred, and propylene glycol monomethyl ether acetate, ethyl ethoxypropionate. 2-heptanone is most preferred.
The mixing ratio (mass) of the solvent containing a hydroxyl group and the solvent not containing a hydroxyl group is 1/99 to 99/1, preferably 10/90 to 90/10, more preferably 20/80 to 60/40. . A mixed solvent containing 50% by mass or more of a solvent not containing a hydroxyl group is particularly preferred from the viewpoint of coating uniformity.

The solvent is preferably a mixed solvent of two or more containing propylene glycol monomethyl ether acetate.
The solid content concentration when the resist composition of the present invention is dissolved in a solvent is usually 1.0 to 10% by mass, preferably 2.0 to 5.7% by mass, more preferably 2.0 to 5%. 3% by mass. In the present invention, the solid content concentration is the mass percentage of the mass of other resist components excluding the solvent with respect to the total mass of the resist composition.
By setting the solid content concentration within the above range, it is possible to uniformly apply the resist solution on the substrate and to form a resist pattern having excellent line edge roughness. The reason for this is not clear, but it is likely that the solid content concentration is 10% by mass or less, preferably 5.7% by mass or less, so that the aggregation of the material in the resist solution is suppressed. It is considered that a resist film was formed.

(D) Resin having at least one of fluorine atom and silicon atom The negative developing resist composition of the present invention preferably contains a resin (D) having at least one of fluorine atom and silicon atom.
The fluorine atom or silicon atom in the resin (D) may be contained in the main chain of the resin or may be substituted with a side chain.

The resin (D) is preferably a resin having, as a partial structure having a fluorine atom, an alkyl group having a fluorine atom, a cycloalkyl group having a fluorine atom, or an aryl group having a fluorine atom.
The alkyl group having a fluorine atom (preferably having 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms) is a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, It may have a substituent.
The cycloalkyl group having a fluorine atom is a monocyclic or polycyclic cycloalkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and may further have another substituent.
Examples of the aryl group having a fluorine atom include those in which at least one hydrogen atom of an aryl group such as a phenyl group or a naphthyl group is substituted with a fluorine atom, and the aryl group may further have another substituent.

  Specific examples of the alkyl group having a fluorine atom, the cycloalkyl group having a fluorine atom, or the aryl group having a fluorine atom are shown below, but the present invention is not limited thereto.

In general formulas (F2) to (F4),
R _{57 to} R ₆₈ each independently represents a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _{57 to} R ₆₁ , R _{62 to} R ₆₄ and R _{65 to} R ₆₈ is a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom (preferably having a carbon number of 1 ~ 4). R _{57 to} R ₆₁ and R _{65 to} R ₆₇ are preferably all fluorine atoms. R ₆₂ , R ₆₃ and R ₆₈ are preferably an alkyl group (preferably having 1 to 4 carbon atoms) in which at least one hydrogen atom is substituted with a fluorine atom, and preferably a perfluoroalkyl group having 1 to 4 carbon atoms. Further preferred. R ₆₂ and R ₆₃ may be connected to each other to form a ring.

  Preferably, the resin (D) contains a structure represented by the following general formula (F3a).

一般式（Ｆ３ａ）に於いて、
Ｒ_62a及びＲ_63aは、各々独立に、少なくとも１つの水素原子がフッ素原子で置換されたアルキル基を表す。Ｒ_62aとＲ_63aは、互いに連結して環を形成してもよい。
Ｒ_64aは、水素原子、フッ素原子又はアルキル基を表す。

In general formula (F3a),
R _62a and R _63a each independently represents an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom. R _62a and R _63a may be connected to each other to form a ring.
R _64a represents a hydrogen atom, a fluorine atom or an alkyl group.

Specific examples of the group represented by the general formula (F2) include a p-fluorophenyl group, a pentafluorophenyl group, and a 3,5-di (trifluoromethyl) phenyl group.
Specific examples of the group represented by the general formula (F3) include trifluoroethyl group, pentafluoropropyl group, pentafluoroethyl group, heptafluorobutyl group, hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro (2 -Methyl) isopropyl group, nonafluorobutyl group, octafluoroisobutyl group, nonafluorohexyl group, nonafluoro-t-butyl group, perfluoroisopentyl group, perfluorooctyl group, perfluoro (trimethyl) hexyl group, 2,2 1,3,3-tetrafluorocyclobutyl group, perfluorocyclohexyl group and the like. Hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro (2-methyl) isopropyl group, octafluoroisobutyl group, nonafluoro-t-butyl group and perfluoroisopentyl group are preferable, and hexafluoroisopropyl group and heptafluoroisopropyl group are preferable. Further preferred.
Specific examples of the group represented by the general formula (F4) include, for example, —C (CF ₃ ) ₂ OH, —C (C ₂ F ₅ ) ₂ OH, —C (CF ₃ ) (CH ₃ ) OH, -CH (CF ₃₎ OH and the like, -C (CF _{3) 2} OH is preferred.

The resin (D) is preferably a resin having an alkylsilyl structure (preferably a trialkylsilyl group) or a cyclic siloxane structure as a partial structure having a silicon atom.
Specific examples of the alkylsilyl structure or the cyclic siloxane structure include groups represented by the following general formulas (CS-1) to (CS-3).

In general formulas (CS-1) to (CS-3),
R _{12 to} R ₂₆ each independently represents a linear or branched alkyl group (preferably having 1 to 20 carbon atoms) or a cycloalkyl group (preferably having 3 to 20 carbon atoms).
L < ₃ > -L < ₅ > represents a single bond or a bivalent coupling group. As the divalent linking group, an alkylene group, a phenyl group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a urethane group, or a urea group is used alone or in combination of two or more groups. A combination is mentioned.
n represents an integer of 1 to 5.

  The resin (D) is preferably a resin having at least one selected from the group of repeating units represented by the following general formulas (CI) to (C-IV).

In the general formulas (CI) to (C-IV),
R _{1 to} R ₃ are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched fluorinated alkyl group having 1 to 4 carbon atoms. Represents a group.
W _{1 to} W ₂ represent an organic group having at least one of a fluorine atom and a silicon atom.
R _{4 to} R ₇ are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched fluorinated alkyl group having 1 to 4 carbon atoms. Represents a group. However, at least one of R _{4 to} R ₇ represents a fluorine atom. R ₄ and R ₅ or R ₆ and R ₇ may form a ring.
R ₈ represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms.
R ₉ represents a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched fluorinated alkyl group having 1 to 4 carbon atoms.
L < ₁ > -L < ₂ > represents a single bond or a bivalent coupling group, and is the same as said L < ₃ > -L < ₅ >.
Q represents a monocyclic or polycyclic cyclic aliphatic group. That is, it represents an atomic group that contains two bonded carbon atoms (C—C) and forms an alicyclic structure.

  The general formula (CI) is more preferably the following general formulas (C-Ia) to (C-Id).

In the general formulas (C-Ia) to (C-Id),
R ₁₀ and R ₁₁ represent a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched fluorinated alkyl group having 1 to 4 carbon atoms.
W _{3 to} W ₆ represent an organic group having at least one of a fluorine atom and a silicon atom.

When W _{1 to} W ₆ are an organic group having a fluorine atom, the fluorinated straight chain, branched alkyl group or cycloalkyl group having 1 to 20 carbon atoms, or the fluorinated group having 1 to 20 carbon atoms. It is preferably a linear, branched, or cyclic alkyl ether group.

Examples of the fluorinated alkyl group for W _{1 to} W ₆ include trifluoroethyl group, pentafluoropropyl group, hexafluoroisopropyl group, hexafluoro (2-methyl) isopropyl group, heptafluorobutyl group, heptafluoroisopropyl group, octafluoro Examples thereof include an isobutyl group, a nonafluorohexyl group, a nonafluoro-t-butyl group, a perfluoroisopentyl group, a perfluorooctyl group, and a perfluoro (trimethyl) hexyl group.

When W _{1 to} W ₆ are organic groups having a silicon atom, an alkylsilyl structure or a cyclic siloxane structure is preferable. Specific examples include groups represented by the general formulas (CS-1) to (CS-3).

Specific examples of the repeating unit represented by the general formula (CI) are shown below. X represents a hydrogen atom, —CH ₃ , —F, or —CF ₃ .

The resin (D) is preferably any resin selected from the following (D-1) to (D-6).
(D-1) A resin having a repeating unit (a) having a fluoroalkyl group (preferably having 1 to 4 carbon atoms), more preferably a resin having only a repeating unit (a).
(D-2) A resin having a repeating unit (b) having a trialkylsilyl group or a cyclic siloxane structure, more preferably a resin having only a repeating unit (b).
(D-3) a repeating unit (a) having a fluoroalkyl group (preferably having 1 to 4 carbon atoms), a branched alkyl group (preferably having 4 to 20 carbon atoms), a cycloalkyl group (preferably having 4 carbon atoms) To 20), a repeating unit (c) having a branched alkenyl group (preferably having 4 to 20 carbon atoms), a cycloalkenyl group (preferably having 4 to 20 carbon atoms) or an aryl group (preferably having 4 to 20 carbon atoms). More preferably, a copolymer resin of the repeating unit (a) and the repeating unit (c).
(D-4) a repeating unit (b) having a trialkylsilyl group or a cyclic siloxane structure, a branched alkyl group (preferably having 4 to 20 carbon atoms), a cycloalkyl group (preferably having 4 to 20 carbon atoms), Resin having a repeating unit (c) having a branched alkenyl group (preferably having 4 to 20 carbon atoms), a cycloalkenyl group (preferably having 4 to 20 carbon atoms) or an aryl group (preferably having 4 to 20 carbon atoms) More preferably, a copolymer resin of the repeating unit (b) and the repeating unit (c).
(D-5) A resin having a repeating unit (a) having a fluoroalkyl group (preferably having 1 to 4 carbon atoms) and a repeating unit (b) having a trialkylsilyl group or a cyclic siloxane structure, more preferably a repeating unit Copolymer resin of unit (a) and repeating unit (b).
(D-6) a repeating unit (a) having a fluoroalkyl group (preferably having 1 to 4 carbon atoms), a repeating unit (b) having a trialkylsilyl group or a cyclic siloxane structure, and a branched alkyl group (preferably Is a C4-20), cycloalkyl group (preferably C4-20), branched alkenyl group (preferably C4-20), cycloalkenyl group (preferably C4-20) or aryl. A resin having a repeating unit (c) having a group (preferably having 4 to 20 carbon atoms), more preferably a copolymer resin of repeating unit (a), repeating unit (b) and repeating unit (c).
Repeating unit (c) having a branched alkyl group, a cycloalkyl group, a branched alkenyl group, a cycloalkenyl group, or an aryl group in the resins (D-3), (D-4), and (D-6) In consideration of hydrophilicity / hydrophobicity, interaction, etc., an appropriate functional group can be introduced, but from the viewpoint of receding contact angle, a functional group having no polar group is preferred.
In the resins (D-3), (D-4), and (D-6), the repeating unit (a) having a fluoroalkyl group and / or the repeating unit (b) having a trialkylsilyl group or a cyclic siloxane structure is It is preferable that it is 20-99 mol%.

  The resin (D) is preferably a resin having a repeating unit represented by the following general formula (Ia).

In general formula (Ia):
Rf represents a hydrogen atom, a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom.
R ₁ represents an alkyl group.
R ₂ represents a hydrogen atom or an alkyl group.

In general formula (Ia), the alkyl group in which at least one hydrogen atom of Rf is substituted with a fluorine atom preferably has 1 to 3 carbon atoms, and more preferably a trifluoromethyl group.
The alkyl group represented by R ₁ is preferably a linear or branched alkyl group having 3 to 10 carbon atoms, and more preferably a branched alkyl group having 3 to 10 carbon atoms.
The alkyl group for R ₂ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms.

Hereinafter, although the specific example of the repeating unit represented by general formula (Ia) is given, this invention is not limited to this. In the formula, X represents a hydrogen atom, a fluorine atom or a CF ₃ group.

  The repeating unit represented by the general formula (Ia) can be formed by polymerizing a compound represented by the following general formula (I).

In general formula (I),
Rf represents a hydrogen atom, a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom.
R ₁ represents an alkyl group.
R ₂ represents a hydrogen atom or an alkyl group.

In the general formula (I), Rf, R ₁ and R ₂ are in the general formula (Ia), Rf, R ₁ and R ₂ synonymous.
As the compound represented by the general formula (I), a commercially available product may be used, or a synthesized product may be used. In the case of synthesis, 2-trifluoromethylmethacrylic acid can be obtained by acidification and then esterification.

  The resin (D) is preferably a resin having a repeating unit represented by the following general formula (II) or a repeating unit represented by the following general formula (III).

In general formulas (II) and (III):
Rf represents a hydrogen atom, a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom.
R ₃ represents an alkyl group, a cycloalkyl group, an alkenyl group or a cycloalkenyl group.
R ₄ represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, a trialkylsilyl group, or a group having a cyclic siloxane structure.
L ₆ represents a single bond or a divalent linking group.
0 <m <100.
0 <n <100.

Rf in the general formula (II) is the same as Rf in the general formula (Ia).
The alkyl group represented by R ₃ is preferably a linear or branched alkyl group having 3 to 20 carbon atoms.
The cycloalkyl group is preferably a cycloalkyl group having 3 to 20 carbon atoms.
The alkenyl group is preferably an alkenyl group having 3 to 20 carbon atoms.
The cycloalkenyl group is preferably a cycloalkenyl group having 3 to 20 carbon atoms.
m = 30 to 70 and n = 30 to 70 are preferable, and m = 40 to 60 and n = 40 to 60 are more preferable.

In general formula (III), the alkyl group represented by R ₄ is preferably a linear or branched alkyl group having 3 to 20 carbon atoms.
The cycloalkyl group is preferably a cycloalkyl group having 3 to 20 carbon atoms.
The alkenyl group is preferably an alkenyl group having 3 to 20 carbon atoms.
The cycloalkenyl group is preferably a cycloalkenyl group having 3 to 20 carbon atoms.
The trialkylsilyl group is preferably a trialkylsilyl group having 3 to 20 carbon atoms.
The group having a cyclic siloxane structure is preferably a group having a cyclic siloxane structure having 3 to 20 carbon atoms.
The divalent linking group of L ₆ is preferably an alkylene group (preferably having 1 to 5 carbon atoms) or an oxy group.

  Hereinafter, although the specific example of resin (D) which has a repeating unit represented by general formula (Ia) is given, this invention is not limited to this.

  Resin (D) may have a repeating unit represented by the following general formula (VIII).

In general formula (VIII):
Z ₂ represents —O— or —N (R ₄₁ ) —. R ₄₁ represents a hydrogen atom, an alkyl group, or —OSO ₂ —R ₄₂ . R ₄₂ represents an alkyl group, a cycloalkyl group or a camphor residue. The alkyl group of R ₄₁ and R ₄₂ may be substituted with a halogen atom (preferably a fluorine atom) or the like.

  The resin (D) is preferably stable to an acid and insoluble in an alkaline developer. Moreover, it is preferable that it is resin soluble in a negative developing solution.

The resin (D) is preferably a resin that is stable to acids and insoluble in an alkaline developer. Specifically, it is preferable from the viewpoint of the followability of the immersion liquid that it does not have an alkali-soluble group and a group whose solubility in a developing solution is increased by the action of acid or alkali.
The total amount of repeating units having an alkali-soluble group in the resin (D) or a group whose solubility in a developer is increased by the action of an acid or an alkali is preferably 20 with respect to all the repeating units constituting the resin (D). It is not more than mol%, more preferably 0 to 10 mol%, still more preferably 0 to 5 mol%.
In addition, if the resin (D) contains a hydrophilic polar group, the followability of immersion water tends to decrease, and therefore does not have a polar group selected from a hydroxyl group, an alkylene glycol, an ether group, and a sulfone group. Is more preferable.

  (X) Examples of alkali-soluble groups include phenolic hydroxyl groups, carboxylic acid groups, fluorinated alcohol groups, sulfonic acid groups, sulfonamido groups, sulfonylimide groups, (alkylsulfonyl) (alkylcarbonyl) methylene groups, and (alkylsulfonyl). ) (Alkylcarbonyl) imide group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, tris ( And a group having an alkylsulfonyl) methylene group.

  (Y) Examples of the group that decomposes by the action of an alkali (alkaline developer) and increases the solubility in the alkali developer include a lactone group, an ester group, a sulfonamide group, an acid anhydride, and an acid imide group. Can be mentioned.

  (Z) Examples of the group that decomposes by the action of an acid and increases the solubility in a developer include the same groups as the acid-decomposable groups in the acid-decomposable resin (A).

  However, the repeating unit represented by the following general formula (pA-c) has no or very little decomposability due to the action of acid as compared with the acid-decomposable group of the resin (A), and is substantially non-acid-decomposable Considered equivalent to gender.

In the general formula (pA-c),
Rp ₂ represents a hydrocarbon group having a tertiary carbon atom bonded to the oxygen atom in the formula.

  When the resin (D) has a silicon atom, the content of the silicon atom is preferably 2 to 50% by mass and more preferably 2 to 30% by mass with respect to the molecular weight of the resin (D). Moreover, it is preferable that the repeating unit containing a silicon atom is 10-100 mass% in resin (D), and it is more preferable that it is 20-100 mass%.

  When resin (D) has a fluorine atom, the fluorine atom content is preferably 5 to 80% by mass and more preferably 10 to 80% by mass with respect to the molecular weight of resin (D). Moreover, it is preferable that the repeating unit containing a fluorine atom is 10-100 mass% in resin (D), and it is more preferable that it is 30-100 mass%.

  The weight average molecular weight in terms of standard polystyrene of the resin (D) is preferably 1,000 to 100,000, more preferably 1,000 to 50,000, and still more preferably 2,000 to 15,000.

  The degree of dispersion (molecular weight distribution) of the resin (D) is usually 1 to 5, preferably 1 to 3, more preferably 1 to 2, particularly preferably 1 to 1.7. The smaller the degree of dispersion, the better the roughness.

  The resin (D) preferably has a residual monomer amount of 0 to 10% by mass, more preferably 0 to 5% by mass, and still more preferably 0 to 1% by mass. The molecular weight distribution (Mw / Mn, also referred to as dispersity) is preferably 1 to 5, more preferably 1 to 3, and still more preferably 1 in terms of resolution, resist shape, resist pattern sidewall, roughness, and the like. It is in the range of ~ 1.5.

  The addition amount of the resin (D) in the negative developing resist composition is preferably 0.1 to 5% by mass, more preferably 0.2 to 3%, based on the total solid content of the resist composition. It is 0.0 mass%, More preferably, it is 0.3-2.0 mass%.

  Resin (D), like acid-decomposable resin (A), naturally has few impurities such as metals, but the residual monomer and oligomer components are not more than predetermined values, for example, 0.1% by mass by HPLC. It is preferable that not only the sensitivity, resolution, process stability, pattern shape and the like as a resist can be further improved, but also a resist having no temporal change such as foreign matter in liquid or sensitivity can be obtained.

  As the resin (D), various commercially available products can be used, or they can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, a monomer polymerization method in which a monomer species and an initiator are dissolved in a solvent and heating is performed, and a solution of the monomer species and the initiator is dropped into the heating solvent over 1 to 10 hours. The dropping polymerization method is added, and the dropping polymerization method is preferable. Examples of the reaction solvent include ethers such as tetrahydrofuran, 1,4-dioxane and diisopropyl ether, ketones such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate, amide solvents such as dimethylformamide and dimethylacetamide, Furthermore, the solvent which melt | dissolves the composition of this invention like the below-mentioned propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and cyclohexanone is mentioned. More preferably, the polymerization is performed using the same solvent as that used in the resist composition of the present invention. Thereby, generation | occurrence | production of the particle at the time of a preservation | save can be suppressed.

  The polymerization reaction is preferably performed in an inert gas atmosphere such as nitrogen or argon. As a polymerization initiator, a commercially available radical initiator (azo initiator, peroxide, etc.) is used to initiate the polymerization. As the radical initiator, an azo initiator is preferable, and an azo initiator having an ester group, a cyano group, or a carboxyl group is preferable. Preferred examples of the initiator include azobisisobutyronitrile, azobisdimethylvaleronitrile, dimethyl 2,2′-azobis (2-methylpropionate) and the like. The concentration of the reaction is 5 to 50% by mass, preferably 30 to 50% by mass. The reaction temperature is usually from 10 ° C to 150 ° C, preferably from 30 ° C to 120 ° C, more preferably from 60 ° C to 100 ° C.

  After completion of the reaction, the mixture is allowed to cool to room temperature and purified. Purification can be accomplished by a liquid-liquid extraction method that removes residual monomers and oligomer components by combining water and an appropriate solvent, and a purification method in a solution state such as ultrafiltration that extracts and removes only those having a specific molecular weight or less. , Reprecipitation method that removes residual monomer by coagulating resin in poor solvent by dripping resin solution into poor solvent and purification in solid state such as washing filtered resin slurry with poor solvent A normal method such as a method can be applied. For example, the resin is precipitated as a solid by contacting a solvent (poor solvent) in which the resin is hardly soluble or insoluble in a volume amount of 10 times or less, preferably 10 to 5 times that of the reaction solution.

  The solvent (precipitation or reprecipitation solvent) used in the precipitation or reprecipitation operation from the polymer solution may be a poor solvent for the polymer. For example, hydrocarbon (pentane, hexane, Aliphatic hydrocarbons such as heptane and octane; Cycloaliphatic hydrocarbons such as cyclohexane and methylcyclohexane; Aromatic hydrocarbons such as benzene, toluene and xylene), halogenated hydrocarbons (methylene chloride, chloroform, carbon tetrachloride, etc.) Halogenated aliphatic hydrocarbons; halogenated aromatic hydrocarbons such as chlorobenzene and dichlorobenzene), nitro compounds (nitromethane, nitroethane, etc.), nitriles (acetonitrile, benzonitrile, etc.), ethers (diethyl ether, diisopropyl ether, dimethoxyethane) Chain A Cyclic ethers such as tetrahydrofuran and dioxane), ketones (acetone, methyl ethyl ketone, diisobutyl ketone, etc.), esters (ethyl acetate, butyl acetate, etc.), carbonates (dimethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, etc.), alcohols ( (Methanol, ethanol, propanol, isopropyl alcohol, butanol, etc.), carboxylic acid (acetic acid, etc.), water, a mixed solvent containing these solvents, and the like. Among these, as a precipitation or reprecipitation solvent, a solvent containing at least an alcohol (particularly methanol or the like) or water is preferable. In such a solvent containing at least hydrocarbon, the ratio of alcohol (particularly methanol) and other solvent (for example, ester such as ethyl acetate, ethers such as tetrahydrofuran) is, for example, the former / the latter (volume ratio). 25 ° C.) = 10/90 to 99/1, preferably the former / the latter (volume ratio; 25 ° C.) = 30/70 to 98/2, more preferably the former / the latter (volume ratio; 25 ° C.) = 50 / It is about 50 to 97/3.

  The amount of the precipitation or reprecipitation solvent used can be appropriately selected in consideration of efficiency, yield, and the like, but generally 100 to 10000 parts by mass, preferably 200 to 2000 parts by mass with respect to 100 parts by mass of the polymer solution, More preferably, it is 300-1000 mass parts.

  The nozzle diameter at the time of supplying the polymer solution to the precipitation or reprecipitation solvent (poor solvent) is preferably 4 mmφ or less (for example, 0.2 to 4 mmφ). Moreover, the supply speed (dropping speed) of the polymer solution into the poor solvent is, for example, about 0.1 to 10 m / second, preferably about 0.3 to 5 m / second, as the linear speed.

  The precipitation or reprecipitation operation is preferably performed with stirring. As a stirring blade used for stirring, for example, a desk turbine, a fan turbine (including a paddle), a curved blade turbine, an arrow blade turbine, a fiddler type, a bull margin type, an angled blade fan turbine, a propeller, a multistage type, an anchor type (or Horseshoe type), gate type, double ribbon, screw, etc. can be used. Stirring is preferably further performed for 10 minutes or more, particularly 20 minutes or more after the supply of the polymer solution. When the stirring time is short, the monomer content in the polymer particles may not be sufficiently reduced. Further, the polymer solution and the poor solvent can be mixed and stirred using a line mixer instead of the stirring blade.

  The temperature for precipitation or reprecipitation can be appropriately selected in consideration of efficiency and operability, but is usually about 0 to 50 ° C., preferably around room temperature (for example, about 20 to 35 ° C.). The precipitation or reprecipitation operation can be performed by a known method such as a batch method or a continuous method using a conventional mixing vessel such as a stirring tank.

  The precipitated or re-precipitated particulate polymer is usually subjected to conventional solid-liquid separation such as filtration and centrifugation, and dried before use. Filtration is performed using a solvent-resistant filter medium, preferably under pressure. Drying is performed at a temperature of about 30 to 100 ° C., preferably about 30 to 50 ° C. under normal pressure or reduced pressure (preferably under reduced pressure).

In addition, once the resin is precipitated and separated, it may be dissolved again in a solvent, and the resin may be brought into contact with a hardly soluble or insoluble solvent.
That is, after completion of the radical polymerization reaction, a solvent in which the polymer is hardly soluble or insoluble is brought into contact, the resin is precipitated (step a), the resin is separated from the solution (step b), and dissolved again in the solvent. (Step c), and then contact the resin solution A with a solvent in which the resin is hardly soluble or insoluble in a volume amount less than 10 times that of the resin solution A (preferably 5 times or less volume). This may be a method including precipitating a resin solid (step d) and separating the precipitated resin (step e).
The solvent used in the preparation of the resin solution A can be the same solvent as the solvent that dissolves the monomer in the polymerization reaction, and may be the same as or different from the solvent used in the polymerization reaction.

  Hereinafter, although the specific example of resin (D) is shown, this invention is not limited to these.

(E) Basic compound The resist composition of the present invention preferably contains (E) a basic compound in order to reduce a change in performance over time from exposure to heating.
Preferred examples of the basic compound include compounds having structures represented by the following formulas (A) to (E).

In general formulas (A) and (E),
R ²⁰⁰ , R ²⁰¹ and R ²⁰² may be the same or different, and are a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms), a cycloalkyl group (preferably having 3 to 20 carbon atoms) or an aryl group (having a carbon number). 6-20), wherein R ²⁰¹ and R ²⁰² may combine with each other to form a ring.

About the said alkyl group, as an alkyl group which has a substituent, a C1-C20 aminoalkyl group, a C1-C20 hydroxyalkyl group, or a C1-C20 cyanoalkyl group is preferable.
R ²⁰³ , R ²⁰⁴ , R ²⁰⁵ and R ²⁰⁶ may be the same or different and each represents an alkyl group having 1 to 20 carbon atoms.
The alkyl groups in the general formulas (A) and (E) are more preferably unsubstituted.

  Preferred compounds include guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, piperidine and the like, and more preferred compounds include imidazole structure, diazabicyclo structure, onium hydroxide structure, onium carboxylate Examples thereof include a compound having a structure, a trialkylamine structure, an aniline structure or a pyridine structure, an alkylamine derivative having a hydroxyl group and / or an ether bond, and an aniline derivative having a hydroxyl group and / or an ether bond.

Examples of the compound having an imidazole structure include imidazole, 2,4,5-triphenylimidazole, and benzimidazole. Examples of the compound having a diazabicyclo structure include 1,4-diazabicyclo [2,2,2] octane, 1,5-diazabicyclo [4,3,0] non-5-ene, and 1,8-diazabicyclo [5,4,0. ] Undecar 7-ene etc. are mentioned. Examples of the compound having an onium hydroxide structure include triarylsulfonium hydroxide, phenacylsulfonium hydroxide, sulfonium hydroxide having a 2-oxoalkyl group, specifically triphenylsulfonium hydroxide, tris (t-butylphenyl) sulfonium. Examples thereof include hydroxide, bis (t-butylphenyl) iodonium hydroxide, phenacylthiophenium hydroxide, and 2-oxopropylthiophenium hydroxide. As the compound having an onium carboxylate structure, an anion portion of the compound having an onium hydroxide structure is converted to a carboxylate, and examples thereof include acetate, adamantane-1-carboxylate, and perfluoroalkylcarboxylate. Examples of the compound having a trialkylamine structure include tri (n-butyl) amine and tri (n-octyl) amine. Examples of the aniline compound include 2,6-diisopropylaniline, N, N-dimethylaniline, N, N-dibutylaniline, N, N-dihexylaniline and the like. Examples of the alkylamine derivative having a hydroxyl group and / or an ether bond include ethanolamine, diethanolamine, triethanolamine, and tris (methoxyethoxyethyl) amine. Examples of aniline derivatives having a hydroxyl group and / or an ether bond include N, N-bis (hydroxyethyl) aniline.
These basic compounds are used alone or in combination of two or more.

  The usage-amount of a basic compound is 0.001-10 mass% normally based on solid content of a resist composition, Preferably it is 0.01-5 mass%.

  The use ratio of the acid generator and the basic compound in the composition is preferably acid generator / basic compound (molar ratio) = 2.5 to 300. In other words, the molar ratio is preferably 2.5 or more from the viewpoint of sensitivity and resolution, and is preferably 300 or less from the viewpoint of suppressing the reduction in resolution due to the thickening of the resist pattern over time until post-exposure heat treatment. The acid generator / basic compound (molar ratio) is more preferably 5.0 to 200, still more preferably 7.0 to 150.

(F) Surfactant The resist composition of the present invention preferably further contains (F) a surfactant, and is a fluorine-based and / or silicon-based surfactant (fluorine-based surfactant, silicon-based surfactant). , A surfactant having both a fluorine atom and a silicon atom), or more preferably two or more.

When the resist composition of the present invention contains the surfactant (F), when using an exposure light source of 250 nm or less, particularly 220 nm or less, a resist pattern with good sensitivity and resolution and less adhesion and development defects can be obtained. It becomes possible to give.
Examples of the fluorine-based and / or silicon-based surfactant include, for example, JP-A No. 62-36663, JP-A No. 61-226746, JP-A No. 61-226745, JP-A No. 62-170950, JP 63-34540 A, JP 7-230165 A, JP 8-62834 A, JP 9-54432 A, JP 9-5988 A, JP 2002-277862 A, US Patent Nos. 5,405,720, 5,360,692, 5,529,881, 5,296,330, 5,436,098, 5,576,143, 5,294,511, 5,824,451 Surfactant can be mentioned, The following commercially available surfactant can also be used as it is.
Examples of commercially available surfactants that can be used include EFTOP EF301 and EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430, 431 and 4430 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176 and F189. , F113, F110, F177, F120, R08 (manufactured by Dainippon Ink & Chemicals, Inc.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (manufactured by Asahi Glass Co., Ltd.), Troisol S-366 (Manufactured by Troy Chemical Co., Ltd.), GF-300, GF-150 (manufactured by Toa Gosei Chemical Co., Ltd.), Surflon S-393 (manufactured by Seimi Chemical Co., Ltd.), F-top EF121, EF122A, EF122B, RF122C, EF125M , EF135M, EF351, 352, EF801, EF802, EF 01 (manufactured by Gemco), PF636, PF656, PF6320, PF6520 (manufactured by OMNOVA), FTX-204D, 208G, 218G, 230G, 204D, 208D, 212D, 218, 222D (manufactured by Neos) Fluorine type surfactant or silicon type surfactant can be mentioned. Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

In addition to the known surfactants described above, surfactants are derived from fluoroaliphatic compounds produced by the telomerization method (also referred to as the telomer method) or the oligomerization method (also referred to as the oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.
As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. Or may be block copolymerized. Examples of the poly (oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group, a poly (oxybutylene) group, and the like, and a poly (oxyethylene, oxypropylene, and oxyethylene group). A unit having different chain lengths in the same chain length, such as a block link) or poly (block link of oxyethylene and oxypropylene) may be used. Furthermore, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer but also a monomer having two or more different fluoroaliphatic groups, Further, it may be a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different (poly (oxyalkylene)) acrylates (or methacrylates).

Examples of commercially available surfactants include Megafac F178, F-470, F-473, F-475, F-476, and F-472 (Dainippon Ink Chemical Co., Ltd.). Further, a copolymer of an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), an acrylate (or methacrylate) having a C ₃ F ₇ group and (poly (oxy And a copolymer of (ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate).

  In the present invention, other surfactants other than fluorine-based and / or silicon-based surfactants can also be used. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether, etc. Sorbitans such as polyoxyethylene alkyl allyl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate Fatty acid esters, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopal Te - DOO, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, may be mentioned polyoxyethylene sorbitan tristearate nonionic surfactants of polyoxyethylene sorbitan fatty acid esters such as such.

  These surfactants may be used alone or in several combinations.

  (F) The usage-amount of surfactant becomes like this. Preferably it is 0.01-10 mass% with respect to resist composition whole quantity (except a solvent), More preferably, it is 0.1-5 mass%.

(G) Carboxylic acid onium salt The resist composition in the present invention may contain (G) a carboxylic acid onium salt. Examples of the carboxylic acid onium salt include a carboxylic acid sulfonium salt, a carboxylic acid iodonium salt, and a carboxylic acid ammonium salt. In particular, the (G) carboxylic acid onium salt is preferably an iodonium salt or a sulfonium salt. Furthermore, it is preferable that the carboxylate residue of the (G) carboxylic acid onium salt of the present invention does not contain an aromatic group or a carbon-carbon double bond. As a particularly preferable anion moiety, a linear, branched, monocyclic or polycyclic alkylcarboxylic acid anion having 1 to 30 carbon atoms is preferable. More preferably, an anion of a carboxylic acid in which some or all of these alkyl groups are fluorine-substituted is preferable. The alkyl chain may contain an oxygen atom. This ensures transparency with respect to light of 220 nm or less, improves sensitivity and resolution, and improves density dependency and exposure margin.

  Fluorine-substituted carboxylic acid anions include fluoroacetic acid, difluoroacetic acid, trifluoroacetic acid, pentafluoropropionic acid, heptafluorobutyric acid, nonafluoropentanoic acid, perfluorododecanoic acid, perfluorotridecanoic acid, perfluorocyclohexanecarboxylic acid, 2 , 2-bistrifluoromethylpropionic acid anion and the like.

  These (G) carboxylic acid onium salts can be synthesized by reacting sulfonium hydroxide, iodonium hydroxide, ammonium hydroxide and carboxylic acid with silver oxide in a suitable solvent.

  The content of the carboxylic acid onium salt in the composition is generally 0.1 to 20% by mass, preferably 0.5 to 10% by mass, and more preferably 1%, based on the total solid content of the composition. -7% by mass.

(H) Other additives The resist composition of the present invention further promotes solubility in dyes, plasticizers, photosensitizers, light absorbers, alkali-soluble resins, dissolution inhibitors and developers as necessary. The compound to be made (for example, a phenol compound having a molecular weight of 1000 or less, an alicyclic compound having a carboxyl group, or an aliphatic compound) and the like can be contained.

Such phenolic compounds having a molecular weight of 1000 or less can be obtained by referring to, for example, the methods described in JP-A-4-1222938, JP-A-2-28531, US Pat. No. 4,916,210, European Patent 219294, etc. It can be easily synthesized by those skilled in the art.
Specific examples of alicyclic or aliphatic compounds having a carboxyl group include carboxylic acid derivatives having a steroid structure such as cholic acid, deoxycholic acid, lithocholic acid, adamantane carboxylic acid derivatives, adamantane dicarboxylic acid, cyclohexane carboxylic acid, cyclohexane Examples thereof include, but are not limited to, dicarboxylic acids.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.

Synthesis Example 1 (Synthesis of Resin (D-20))
47.2 g of hexafluoroisopropyl acrylate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in propylene glycol monomethyl ether acetate to prepare 170 g of a solution having a solid content concentration of 20%. To this solution was added 8 mol% (3.68 g) of a polymerization initiator V-601 manufactured by Wako Pure Chemical Industries, Ltd., and this was heated to 80 ° C. over 4 hours under a nitrogen atmosphere, 20.0 g of propylene glycol monomethyl ether acetate. It was dripped in. After completion of dropping, the reaction solution was stirred for 2 hours to obtain a reaction solution (1). After completion of the reaction, the reaction solution (1) was cooled to room temperature and dropped into a 20 times amount of a mixed solvent of methanol / water = 8/1. The separated oily compound was recovered by decantation to obtain 24.1 g of the target resin (D-20).
The weight average molecular weight in terms of standard polystyrene determined by GPC measurement was 7600, and the degree of dispersion (Mw / Mn) was 1.6.

  The other component (D) used in the examples was synthesized in the same manner. The structure of D component is the structure itself shown in the specific example of resin (D). Table 1 summarizes the composition ratio (molar ratio), weight average molecular weight, and degree of dispersion of the resin (D) used in the examples.

Synthesis Example 2 (Synthesis of Resin (A1))
Under a nitrogen stream, 20 g of a 6/4 (mass ratio) mixed solvent of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether was placed in a three-necked flask and heated to 80 ° C. (solvent 1). γ-Butyrolactone methacrylate, hydroxyadamantane methacrylate, 2-methyl-2-adamantyl methacrylate in a mixed solvent of 6/4 (mass ratio) of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether in a molar ratio of 40/25/35 It melt | dissolved and the 22 mass% monomer solution (200g) was prepared. Furthermore, 8 mol% of initiator V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) was added to the monomer, and a dissolved solution was dropped into the solvent 1 over 6 hours. After completion of dropping, the reaction was further continued at 80 ° C. for 2 hours. The reaction solution was allowed to cool and then poured into 1800 ml of hexane / 200 ml of ethyl acetate. The precipitated powder was collected by filtration and dried to obtain 37 g of Resin (A1). The weight average molecular weight in terms of standard polystyrene of the obtained resin (A1) was 5500, and the dispersity (Mw / Mn) was 1.65.

  Similarly, resins (A2) to (A8) were synthesized.

  Hereinafter, the structures of the resins (A2) to (A8) are shown. The composition ratio (molar ratio), weight average molecular weight, and degree of dispersion of the resin are summarized in Table 2.

<Preparation of resist composition>
As shown in Table 3 below, each component was dissolved in a solvent to prepare a solution, which was filtered through a 0.05 μm polyethylene filter to prepare resist compositions Ra1 to Ra10, Ra1 ′, Ra6 ′, and Rb1.

  Abbreviations in Table 3 are as follows.

N-1: N, N-diphenylaniline N-2: Diazabicyclo [4.3.0] nonene N-3: 4-Dimethylaminopyridine

W-1: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.) (Fluorine)
W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd.) (fluorine and silicon)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) (silicon-based)
W-4: PF6320 (manufactured by OMNOVA) (fluorine-based)

SL-1: Propylene glycol monomethyl ether acetate SL-2: Propylene glycol monomethyl ether

Evaluation was performed by the following method using the resist composition prepared above.
In the following, Examples 1 to 4, 6, 7, 11 to 23 are reference examples.

Example 1 (negative development)
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 78 nm. A resist composition Ra1 was spin-coated thereon, and baked at 120 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. The obtained wafer was subjected to liquid formation through a mask for pattern formation using pure water as immersion liquid and a PAS5500 / 1250i manufactured by ASML equipped with an NA0.85 lens as an ArF excimer laser scanner. Immersion exposure. After the exposure, the wafer was rotated at 2000 rpm to remove water. After heating at 120 ° C. for 60 seconds, developing with butyl acetate (negative developer) for 60 seconds (negative development), rinsing with 1-hexanol, and rotating the wafer for 30 seconds at 4000 rpm. As a result, an 80 nm (1: 1) line and space resist pattern was obtained.

Examples 2 to 10 and Comparative Example 1 (change in negative development composition)
An 80 nm (1: 1) line-and-space resist pattern was obtained in the same manner as in Example 1 except that the resist composition was changed to Ra2 to Ra10 and Rb1. However, in Example 10, the film thickness was 100 nm.

Comparative Example 2 (positive development only)
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 78 nm. A resist composition Ra6 ′ was spin-coated thereon and baked at 120 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. The obtained wafer was subjected to liquid formation through a mask for pattern formation using pure water as immersion liquid and a PAS5500 / 1250i manufactured by ASML equipped with an NA0.85 lens as an ArF excimer laser scanner. Immersion exposure. After the exposure, the wafer was rotated at 2000 rpm to remove water. Then, after heating at 120 ° C. for 60 seconds, development with a tetramethylammonium hydroxide aqueous solution (2.38% by mass) (positive developer) for 60 seconds (positive development), rinsing with pure water, and 4000 rpm By rotating the wafer for 30 seconds at a rotation speed, an 80 nm (1: 1) line and space resist pattern was obtained.

Example 11 (Combination of negative development and positive development)
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 78 nm. A resist composition Ra1 was spin-coated thereon, and baked at 120 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. The obtained wafer was subjected to liquid formation through a mask for pattern formation using pure water as immersion liquid and a PAS5500 / 1250i manufactured by ASML equipped with an NA0.85 lens as an ArF excimer laser scanner. Immersion exposure. After the exposure, the wafer was rotated at 2000 rpm to remove water. Then, after heating at 120 ° C. for 60 seconds, development with a tetramethylammonium hydroxide aqueous solution (2.38% by mass) (positive developer) for 60 seconds (positive development), rinsing with pure water, a pitch of 320 nm, A pattern with a line width of 240 nm was obtained. Next, development is carried out with butyl acetate (negative developer) for 60 seconds (negative development), rinsed with 1-hexanol, and then the wafer is rotated at 4000 rpm for 30 seconds to obtain 80 nm (1: 1). A line and space resist pattern was obtained.

Example 12 (Combined use of negative development and positive development)
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 78 nm. A resist composition Ra1 was spin-coated thereon, and baked at 120 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. The obtained wafer was subjected to liquid formation through a mask for pattern formation using pure water as immersion liquid and a PAS5500 / 1250i manufactured by ASML equipped with an NA0.85 lens as an ArF excimer laser scanner. Immersion exposure. After the exposure, the wafer was rotated at 2000 rpm to remove water. After heating at 120 ° C. for 60 seconds, developing with butyl acetate (negative developer) for 60 seconds (negative development), rinsing with 1-hexanol, and rotating the wafer for 30 seconds at 4000 rpm. Thus, a pattern having a pitch of 320 nm and a line width of 240 nm was obtained. Next, the film was developed with a tetramethylammonium hydroxide aqueous solution (2.38% by mass) (positive developer) for 60 seconds (positive development), rinsed with pure water, and 80 nm (1: 1) line and space. A resist pattern was obtained.

Examples 13 to 23 (negative development development condition change)
80 nm (1: 1) line-and-space was obtained in the same manner as in Example 1 except that the combination of the resist composition, the negative developer, and the negative developer rinse was changed to the combinations shown in Table 4 below. A resist pattern was obtained.

Scum evaluation 80 nm (1: 1) line-and-space line pattern upper surface and space portion obtained in Examples 1 to 23 and Comparative Examples 1 and 2 were measured with a length-measuring scanning electron microscope (S-9260 manufactured by Hitachi, Ltd.). When the resist residue is not observed at all, it is represented by ◎, when there is almost no resist is represented by ○, when there is a little, it is represented by Δ, and when it is observed remarkably, it is represented by ×. The results are shown in Table 4.

Evaluation of Line Edge Roughness (LER) The 80 nm (1: 1) line and space resist pattern obtained in Examples 1 to 23 and Comparative Examples 1 and 2 was measured using a length-measuring scanning electron microscope (S-9260 manufactured by Hitachi, Ltd.). ), The distance from the reference line where the edge should be 50 points was measured for the range of the edge of 2 μm in the longitudinal direction of the 80 nm line pattern, the standard deviation was obtained, and 3σ was calculated. A smaller value indicates better performance. The results are shown in Table 4.

Evaluation of in-plane uniformity of line width Using an 80 nm (1: 1) line and space resist pattern obtained in Examples 1 to 23 and Comparative Examples 1 and 2 using a scanning microscope (S-9260 manufactured by Hitachi, Ltd.) The dimensions of 50 locations were measured at intervals of 2 mm, the standard deviation at 50 locations was determined, and 3σ was calculated. A smaller value indicates better performance. The results are shown in Table 4.

Evaluation of receding contact angle with respect to water Each resist composition shown in Table 4 was applied on a silicon wafer using a spin coater, and the coating solvent was heated and dried on a hot plate at 120 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. The contact angle of the resist film to pure water was measured using a contact angle meter DM500 manufactured by Kyowa Interface Chemical Co., Ltd. The measurement was performed under conditions of a temperature of 25 ° C. and a humidity of 50%.

Evaluation of water followability A negative resist composition prepared on a silicon wafer was applied and baked at 120 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. Next, as shown in FIG. 4, pure water 2 was filled between the wafer 1 coated with the obtained resist composition and the quartz glass substrate 3.
In this state, the quartz glass substrate 3 was moved (scanned) in parallel to the surface of the resist-coated substrate 1, and the state of the pure water 2 following it was visually observed. Gradually increase the scanning speed of the quartz glass substrate 3 and obtain the limit scanning speed (unit: mm / sec) at which the pure water 2 cannot follow the scanning speed of the quartz glass substrate 3 and water droplets remain on the retreat side. The water followability was evaluated. As this limit scan speed is larger, water can follow a higher scan speed, and the water followability on the resist film is better.

  In Table 4, the weight ratio indicates the mixing weight ratio of the two types of solvents when two types of organic solvents are used together as a negative developer and when two types of organic solvents are used as a negative developer rinse. To express. In this case, the weight ratio when the negative developer or the negative developer rinse solution is composed of a single organic solvent is 100. In Comparative Example 2, the negative development process and the rinsing process after the negative development were not performed, and the aqueous solution of tetramethylammonium hydroxide (2.38% by mass) in the positive development process was used. The rinsing process after the positive development was performed using pure water.

  Table 5 shows the vapor pressures and boiling points of the solvents used in the negative developing solution and the rinsing solution used in this example.

  From the above examples, the negative developing resist composition of the present invention suppresses the occurrence of scum, reduces the line edge roughness, and stabilizes a highly accurate fine pattern with good in-plane line width uniformity. It is clear that it can be formed automatically. Moreover, it can be seen that the negative developing resist composition of the present invention has good followability to the immersion liquid in immersion exposure.

Claims (8)

Contains a resin whose polarity is increased by the action of an acid. Irradiation with actinic rays or radiation increases the solubility in a positive developer that is an alkaline developer, and decreases the solubility in a negative developer containing an organic solvent. Forming a resist film by applying a negative developing resist composition, exposing the resist film through an immersion medium, and performing development using the negative developer. A pattern forming method, wherein the negative developing resist composition contains the following components.
(A) a resin whose polarity is increased by the action of an acid, the solubility in the positive developer is increased by irradiation with actinic rays or radiation, and the solubility in the negative developer is decreased; (B) actinic rays or radiation A compound that generates an acid upon irradiation of (C), (C) a solvent, and (D) at least one of a fluorine atom and a silicon atom, and (x) an alkali-soluble group, and (y) decomposed by the action of an alkali developer. A group that increases the solubility in an alkali developer, (z) a group that decomposes by the action of an acid and increases the solubility in an alkali developer, and a repeating unit represented by the general formula (pA-c). Resin having either.

In the general formula (pA-c),
Rp ₂ represents a hydrocarbon group having a tertiary carbon atom bonded to the oxygen atom in the formula. The pattern forming method according to claim 1, wherein the component (D) has any of a fluorinated alcohol group, a lactone group, and a group represented by —C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ).
R _{36 to} R ₃₈ each independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group, and R ₃₆ and R ₃₇ may be bonded to each other to form a ring. .   The pattern forming method according to claim 1, wherein the organic solvent contained in the negative developer contains an ester solvent.   The pattern formation method as described in any one of Claims 1-3 including wash | cleaning using the rinse liquid containing an organic solvent after image development using the said negative developing solution.   The pattern formation method as described in any one of Claims 1-4 which perform the said exposure using the light of a wavelength of 200 nm or less. The pattern forming method according to claim 1, wherein the immersion medium is water. The (A) component of the said resist composition is resin which has a monocyclic or polycyclic alicyclic hydrocarbon structure, The pattern formation method as described in any one of Claims 1-6. The pattern forming method according to claim 7, wherein the component (A) of the resist composition is a resin having a lactone group and having a monocyclic or polycyclic alicyclic hydrocarbon structure.

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