JP5768789B2 - Resist material and pattern forming method using the same - Google Patents

Description

  The present invention relates to a resist material to which a resin obtained by blending a polymer compound containing a repeating unit derived from a substituted styrene boronic acid and a polymer compound containing a repeating unit having an acid labile group, especially a chemical amplification The present invention relates to a positive resist material and a pattern forming method.

  With the high integration and high speed of LSI, pattern rule miniaturization is progressing rapidly. In particular, the expansion of the flash memory market and the increase in storage capacity are leading to miniaturization. As state-of-the-art miniaturization technology, mass production of 65 nm node devices by ArF lithography has been performed, and preparation for mass production of 45 nm nodes by next generation ArF immersion lithography is in progress. Next generation 32nm node includes immersion lithography with ultra high NA lens combining liquid with higher refractive index than water, high refractive index lens and high refractive index resist film, vacuum ultraviolet light (EUV) with wavelength of 13.5nm Lithography, double exposure of ArF lithography (double patterning lithography), and the like are candidates and are being studied.

Light elements such as hydrocarbons used in resist materials are hardly absorbed by very short wavelength high energy rays such as electron beams (EB) and X-rays, and polyhydroxystyrene-based resist materials have been studied. ing.
The resist material for EB has been practically used for mask drawing. In recent years, mask manufacturing techniques have become a problem. Reduced projection exposure apparatuses have been used since the light used for exposure was g-line, and the reduction magnification was 1/5. However, both the enlargement of the chip size and the enlargement of the projection lens have a 1/4 magnification. Therefore, the influence of the dimensional deviation of the mask on the dimensional change of the pattern on the wafer has become a problem. It has been pointed out that with the miniaturization of the pattern, the dimensional deviation on the wafer has become larger than the value of the dimensional deviation of the mask. There is a need for a mask error enhancement factor (MEEF) calculated using a mask dimensional change as a denominator and a dimensional change on a wafer as a numerator. It is not uncommon for MEEF to exceed 4 for 45 nm-class patterns. If the reduction ratio is 1/4 and the MEEF is 4, it can be said that the mask manufacturing requires accuracy equivalent to that of a substantially equal-size mask.

  In order to increase the accuracy of the line width in the mask manufacturing exposure apparatus, an exposure apparatus using an electron beam (EB) has been used from an exposure apparatus using a laser beam. Furthermore, since further miniaturization is possible by increasing the acceleration voltage in the electron gun of EB, 10 keV to 30 keV, and recently 50 keV is the mainstream, and studies of 100 keV are also underway.

  Here, as the acceleration voltage increases, lowering the sensitivity of the resist film has become a problem. When the acceleration voltage is improved, the influence of forward scattering in the resist film is reduced, so that the contrast of the electron drawing energy is improved and the resolution and dimensional controllability are improved. Since it passes, the sensitivity of the resist film decreases. Since the mask exposure machine exposes by direct drawing with a single stroke, a decrease in sensitivity of the resist film leads to a decrease in productivity, which is not preferable. In view of the demand for higher sensitivity, chemically amplified resist materials are being studied.

With the miniaturization of patterns in mask manufacturing EB lithography, the resist film is becoming thinner in order to prevent pattern collapse during development with a high aspect ratio. In the case of photolithography, the thinning of the resist film greatly contributes to the improvement of the resolution. This is because the planarization of the device has progressed with the introduction of CMP or the like. In the case of mask production, the substrate is flat, and the thickness of the substrate to be processed (for example, Cr, MoSi, SiO ₂ ) is determined for light shielding rate and phase difference control. In order to reduce the thickness, it is necessary to improve the dry etching resistance of the resist film.

Here, it is generally said that there is a correlation between the carbon density of the resist film and the dry etching resistance. In EB drawing that is not affected by absorption, a resist material based on a novolak polymer having excellent etching resistance has been developed.
The indene copolymerization disclosed in Japanese Patent No. 3865048 (Patent Document 1) and the acenaphthylene copolymer disclosed in Japanese Patent Application Laid-Open No. 2006-169302 (Patent Document 2) are not only high in carbon density but also rigid due to the cycloolefin structure. The main chain structure shows improved etching resistance.

In soft X-ray (EUV) exposure at a wavelength of 5 to 20 nm, it is reported that there is little absorption of carbon atoms. Increasing the carbon density is effective not only for improving dry etching resistance but also for improving transmittance in the soft X-ray wavelength region.
As miniaturization progresses, image blur due to acid diffusion has become a problem. In order to ensure the resolution in a fine pattern having a dimension size of 45 nm or more, it is proposed that not only the improvement of dissolution contrast conventionally proposed but also the control of acid diffusion is important. However, chemically amplified resist materials have increased sensitivity and contrast due to acid diffusion, so if you try to minimize acid diffusion by shortening the post-exposure bake (PEB) temperature and time, the sensitivity and contrast are remarkably high. descend. There is a close relationship between the type of acid labile group and the acid diffusion distance, and development of an acid labile group in which the deprotection reaction proceeds with an extremely short acid diffusion distance is desired.

A trade-off relationship between sensitivity, edge roughness and resolution has been reported. Increasing sensitivity degrades edge roughness and resolution, and suppressing acid diffusion improves resolution but decreases edge roughness and sensitivity.
Although it is effective to suppress acid diffusion by adding an acid generator that generates a bulky acid, as described above, the edge roughness and sensitivity are reduced. Therefore, it has been proposed to copolymerize an onium salt acid generator having a polymerizable olefin in the polymer. JP-A-4-230645 (Patent Document 3), JP-A-2005-84365 (Patent Document 4), and JP-A-2006-45311 (Patent Document 5) describe a polymerization property that generates a specific sulfonic acid. Sulfonium salts and iodonium salts having olefins have been proposed. Photoresists using a base polymer copolymerized with a polymerizable acid generator have low acid diffusion because the acid diffusion is small and the acid generator is uniformly dispersed in the polymer, so both edge resolution and resolution are low. The characteristics can be improved at the same time.

  In EUV lithography, there is a problem that an outgas component generated from a resist film during exposure is adsorbed on the surface of a reflection mirror or a mask in the exposure apparatus to reduce the reflectance. In order to reduce outgas, it has been proposed to provide a protective film above the resist film. In this case, a coater cup for coating a protective film is required. In the initial stage of immersion lithography, a protective film was applied to prevent elution of the acid generator from the resist film into water. However, a decrease in throughput and an increase in material cost due to the provision of a protective film have become problems, and the protective film has gradually been discontinued. In consideration of such a background, development of a resist material that reduces outgas without using a protective film is also required in EUV lithography.

  Patent Nos. 4771974 (Patent Document 6) and Japanese Patent No. 4900603 (Patent Document 7) each include a copolymer of a styrene derivative and a repeating unit having a fluorine atom, a vinyl naphthalene and a repeating unit having a fluorine atom. A resist material to which a copolymer is added has been proposed. In these, a polymer having a styrene unit or a vinylnaphthalene unit is oriented on the surface layer after spin coating, and both water repellency and antireflection properties can be obtained. It also mentions that outgassing during EUV exposure can be suppressed. However, it is desired to develop a resist surface modifying material that can not sufficiently suppress outgassing with styrene or vinylnaphthalene units and that can effectively block outgassing.

Japanese Patent No. 3865048 JP 2006-169302 A JP-A-4-230645 JP 2005-84365 A JP 2006-45311 A Japanese Patent No. 4771974 Japanese Patent No. 4900603

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resist material and a pattern forming method capable of reducing the generation of outgas from a resist film in EUV exposure and preventing the occurrence of blob defects.

  The present invention has been made to solve the above-described problems, and includes a polymer compound serving as a base resin whose alkali solubility is improved by an acid, and a repeating unit derived from a substituted styrene boronic acid as a polymer additive. The present invention proposes a resist material and a pattern forming method including a polymer compound.

  That is, according to the present invention, a polymer having a repeating unit derived from a substituted styrene boronic acid is added to the coated photoresist surface by adding a polymer-type surfactant having a repeating unit derived from a substituted styrene boronic acid. Form a layer. A polymer having a repeating unit derived from a substituted styrene boronic acid has a high film density and has an effect of preventing the outgas component generated from the inside of the resist film from being released out of the film. Since the polymer type surfactant with unit dissolves in alkaline developer, the occurrence of blob defects and bridge defects can be suppressed by increasing the hydrophilicity of the resist surface after exposure and development. It has been found that a mask blank resist material having excellent properties and exposure stability in vacuum, an EUV resist material in which generation of outgas in vacuum is reduced, and a pattern forming method using such a material can be provided. Invented the invention.

（式中、Ｒ¹は水素原子、炭素数１〜４の直鎖状又は分岐状のアルキル基、又はハロゲン原子である。Ｒ²、Ｒ³は水素原子、炭素数１〜１０の直鎖状、分岐状又は環状のアルキル基、又は炭素数７〜１０のアラルキル基、又はＲ²とＲ³が結合して−Ｏ−Ｂ−Ｏ−と共に環を形成してもよく、この場合、Ｒ²、Ｒ³は炭素数１〜２０の直鎖状、分岐状又は環状を有するアルキレン基、アルケニレン基又はアラルキレン基であり、エーテル基、チオール基又はヒドロキシ基を有していてもよい。０＜ｐ≦１．０である。）
〔３〕
置換スチレンボロン酸に由来する繰り返し単位ｐを含有する高分子化合物が、更に繰り返し単位ｐに加えて下記一般式（２）で示される繰り返し単位ｑ１〜ｑ４から選ばれる１以上のモノマーに由来する繰り返し単位を共重合してなる〔２〕に記載のレジスト材料。

（式中、Ｒ¹〜Ｒ³は前述と同様である。Ｒ⁴は水素原子又はメチル基、Ｘ¹は単結合、−Ｃ（＝Ｏ）−Ｏ−、又は−Ｏ−であり、Ｘ²、Ｘ³はフェニレン基又はナフチレン基、Ｘ⁴はメチレン基、酸素原子又は硫黄原子である。Ｒ⁵は炭素数６〜２０のアリ−ル基又はアラルキル基で、水酸基、直鎖状、分岐状又は環状のアルキル基又はアルコキシ基、エステル基（−ＯＣＯＲ又は−ＣＯＯＲ：ＲはＣ_1-6のアルキル基）、ケトン基（−ＣＯＲ：ＲはＣ_1-6のアルキル基）、フッ素原子、トリフルオロメチル基、ニトロ基、アミノ基又はシアノ基を有していてもよい。Ｒ⁶、Ｒ⁷、Ｒ⁸、Ｒ⁹は同一又は異種の水素原子、ヒドロキシ基、炭素数１〜１０の直鎖状、分岐状又は環状のアルキル基、アルコキシ基又はアシロキシ基、シアノ基、ニトロ基、アミノ基、ハロゲン原子、エステル基（−ＯＣＯＲ又は−ＣＯＯＲ：ＲはＣ_1-6のアルキル基又はフッ素化アルキル基）、又はカルボキシル基である。ｖは１又は２である。０＜ｐ＜１．０、０≦ｑ１＜１．０、０≦ｑ２＜１．０、０≦ｑ３＜１．０、０≦ｑ４＜１．０、０＜ｑ１＋ｑ２＋ｑ３＋ｑ４＜１．０である。）
〔４〕
化学増幅ポジ型レジスト材料であることを特徴とする〔１〕、〔２〕又は〔３〕に記載のレジスト材料。
〔５〕
前記ベース樹脂としての高分子化合物が、酸不安定基を有する繰り返し単位、及びヒドロキシ基及び／又はラクトン環の密着性基を有する繰り返し単位を含むものであることを特徴とする〔４〕に記載のレジスト材料。
〔６〕
前記ベース樹脂としての高分子化合物において、酸不安定基を有する繰り返し単位が、カルボキシル基及び／又はフェノール基の水酸基の水素原子が酸不安定基で置換されている下記一般式（３）で示される繰り返し単位ａ１、ａ２から選ばれる１つ以上の繰り返し単位であり、高分子化合物の重量平均分子量が１，０００〜５００，０００の範囲であることを特徴とする〔５〕に記載のレジスト材料。

（式中、Ｒ¹⁰、Ｒ¹²はそれぞれ独立に水素原子又はメチル基を表し、Ｒ¹¹、Ｒ¹³は酸不安定基を表す。Ｙ¹は単結合、エステル基，ラクトン環，フェニレン基又はナフチレン基のいずれか１種又は２種以上を有する炭素数１〜１２の連結基、フェニレン基、又はナフチレン基である。Ｙ²は単結合、エステル基、又はアミド基である。０≦ａ１≦０．９、０≦ａ２≦０．９、０＜ａ１＋ａ２＜１．０である。）
〔７〕
前記ベース樹脂としての高分子化合物が、カルボキシル基及び／又はフェノール基の水酸基の水素原子が酸不安定基で置換されている上記一般式（３）で示される繰り返し単位ａ１又はａ２に加えて、下記一般式（４）で示されるスルホニウム塩ｂ１〜ｂ３から選ばれる１つ以上の繰り返し単位を共重合した重量平均分子量が１，０００〜５００，０００の範囲である高分子化合物であることを特徴とする〔６〕に記載のレジスト材料。

（式中、Ｒ⁰²⁰、Ｒ⁰²⁴、Ｒ⁰²⁸は水素原子又はメチル基、Ｒ⁰²¹は単結合、フェニレン基、−Ｏ−Ｒ⁰³³−、又は−Ｃ（＝Ｏ）−Ｙ−Ｒ⁰³³−である。Ｙは酸素原子又はＮＨ、Ｒ⁰³³は炭素数１〜６の直鎖状、分岐状又は環状のアルキレン基、アルケニレン基又はフェニレン基であり、カルボニル基（−ＣＯ−）、エステル基（−ＣＯＯ−）、エーテル基（−Ｏ−）又はヒドロキシ基を含んでいてもよい。Ｒ⁰²²、Ｒ⁰²³、Ｒ⁰²⁵、Ｒ⁰²⁶、Ｒ⁰²⁷、Ｒ⁰²⁹、Ｒ⁰³⁰、Ｒ⁰³¹は同一又は異種の炭素数１〜１２の直鎖状、分岐状又は環状のアルキル基であり、カルボニル基、エステル基又はエーテル基を含んでいてもよく、又は炭素数６〜１２のアリール基、炭素数７〜２０のアラルキル基又はチオフェニル基を表す。Ａ¹は単結合、−Ａ⁰−Ｃ（＝Ｏ）−Ｏ−、−Ａ⁰−Ｏ−又は−Ａ⁰−Ｏ−Ｃ（＝Ｏ）−であり、Ａ⁰は炭素数１〜１２の直鎖状、分岐状又は環状のアルキレン基で、カルボニル基、エステル基又はエーテル基を含んでいてもよい。Ａ²は水素原子又はＣＦ₃基又はカルボニル基である。Ｚ¹は単結合、メチレン基、エチレン基、フェニレン基、フッ素化されたフェニレン基、−Ｏ−Ｒ⁰³²−、又は−Ｃ（＝Ｏ）−Ｚ²−Ｒ⁰³²−である。Ｚ²は酸素原子又はＮＨ、Ｒ⁰³²は炭素数１〜６の直鎖状、分岐状又は環状のアルキレン基、フェニレン基、フッ素化されたフェニレン基、トリフルオロメチル基で置換されたフェニレン基、又はアルケニレン基であり、カルボニル基、エステル基、エーテル基又はヒドロキシ基を含んでいてもよい。Ｍ^-は非求核性対向イオンを表す。０≦ｂ１≦０．３、０≦ｂ２≦０．３、０≦ｂ３≦０．３、０＜ｂ１＋ｂ２＋ｂ３≦０．３である。）
〔８〕
更に、有機溶剤、塩基性化合物、溶解制御剤、界面活性剤のいずれか１つ以上を含有するものであることを特徴とする〔１〕〜〔７〕のいずれかに記載のレジスト材料。
〔９〕
〔１〕〜〔８〕のいずれかに記載のレジスト材料を基板上に塗布する工程と、加熱処理後、高エネルギー線で露光する工程と、現像液を用いて現像する工程とを含むことを特徴とするパターン形成方法。
〔１０〕
前記高エネルギー線が、波長２４８ｎｍのＫｒＦエキシマレーザー、波長１９３ｎｍのＡｒＦエキシマレーザー、電子ビーム、又は波長３〜１５ｎｍの範囲の軟Ｘ線であることを特徴とする〔９〕に記載のパターン形成方法。 That is, the present invention provides the following resist material and a pattern forming method using the same.
[1]
A resist material comprising: a polymer compound serving as a base resin whose alkali solubility is improved by an acid; and a polymer compound having a repeating unit derived from substituted styrene boronic acid as a polymer additive.
[2]
[1] The resist material according to [1], wherein the polymer compound containing the repeating unit p derived from substituted styrene boronic acid has a repeating unit represented by the following general formula (1).

(In the formula, R ¹ is a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a halogen atom. R ² and R ³ are a hydrogen atom and a straight chain having 1 to 10 carbon atoms. , A branched or cyclic alkyl group, an aralkyl group having 7 to 10 carbon atoms, or R ² and R ³ may combine to form a ring with —O—B—O—, in which case R ² , R ³ is a linear, branched or cyclic alkylene group having 1 to 20 carbon atoms, an alkenylene group or an aralkylene group, and may have an ether group, a thiol group or a hydroxy group, 0 <p ≦ 1.0.)
[3]
The polymer compound containing the repeating unit p derived from substituted styrene boronic acid is further derived from one or more monomers selected from repeating units q1 to q4 represented by the following general formula (2) in addition to the repeating unit p. The resist material according to [2], which is obtained by copolymerizing units.

(Wherein R ^{1 to} R ³ are the same as described above, R ⁴ is a hydrogen atom or a methyl group, X ¹ is a single bond, —C (═O) —O—, or —O—, and X ² , X ³ is a phenylene group or a naphthylene group, X ⁴ is a methylene group, an oxygen atom or a sulfur atom, R ⁵ is an aryl group or an aralkyl group having 6 to 20 carbon atoms, and is a hydroxyl group, linear or branched Or a cyclic alkyl group or an alkoxy group, an ester group (—OCOR or —COOR: R is a C _1-6 alkyl group), a ketone group (—COR: R is a C _1-6 alkyl group), a fluorine atom, It may have a fluoromethyl group, a nitro group, an amino group or a cyano group, wherein R ⁶ , R ⁷ , R ⁸ and R ⁹ are the same or different hydrogen atoms, hydroxy groups, and straight-chains having 1 to 10 carbon atoms. , Branched or cyclic alkyl group, alkoxy group or acyloxy group, cyano group, nitro group , An amino group, a halogen atom, an ester group (—OCOR or —COOR: R is a C _1-6 alkyl group or a fluorinated alkyl group), or a carboxyl group, v is 1 or 2. 0 <p < 1.0, 0 ≦ q1 <1.0, 0 ≦ q2 <1.0, 0 ≦ q3 <1.0, 0 ≦ q4 <1.0, 0 <q1 + q2 + q3 + q4 <1.0.)
[4]
The resist material according to [1], [2] or [3], which is a chemically amplified positive resist material.
[5]
The resist according to [4], wherein the polymer compound as the base resin includes a repeating unit having an acid labile group and a repeating unit having a hydroxy group and / or an adhesive group of a lactone ring. material.
[6]
In the polymer compound as the base resin, the repeating unit having an acid labile group is represented by the following general formula (3) in which a hydrogen atom of a hydroxyl group of a carboxyl group and / or a phenol group is substituted with an acid labile group. The resist material according to [5], wherein the weight average molecular weight of the polymer compound is in the range of 1,000 to 500,000. .

(In the formula, R ¹⁰ and R ¹² each independently represent a hydrogen atom or a methyl group, R ¹¹ and R ¹³ each represent an acid labile group. Y ¹ represents a single bond, an ester group, a lactone ring, a phenylene group or a naphthylene. A linking group having 1 to 12 carbon atoms, a phenylene group, or a naphthylene group having any one or more of groups Y ² is a single bond, an ester group, or an amide group, 0 ≦ a1 ≦ 0. .9, 0 ≦ a2 ≦ 0.9, 0 <a1 + a2 <1.0.)
[7]
In addition to the repeating unit a1 or a2 represented by the general formula (3) in which the polymer compound as the base resin is substituted with an acid labile group, a hydrogen atom of a hydroxyl group of a carboxyl group and / or a phenol group, It is a polymer compound having a weight average molecular weight in the range of 1,000 to 500,000 obtained by copolymerizing one or more repeating units selected from sulfonium salts b1 to b3 represented by the following general formula (4). The resist material according to [6].

Wherein R ⁰²⁰ , R ⁰²⁴ and R ⁰²⁸ are a hydrogen atom or a methyl group, R ⁰²¹ is a single bond, a phenylene group, —O—R ⁰³³ —, or —C (═O) —Y—R ⁰³³ —. Y is an oxygen atom or NH, and R ⁰³³ is a linear, branched or cyclic alkylene group, alkenylene group or phenylene group having 1 to 6 carbon atoms, a carbonyl group (—CO—), an ester group (—COO) -), An ether group (-O-) or a hydroxy group, R ⁰²² , R ⁰²³ , R ⁰²⁵ , R ⁰²⁶ , R ⁰²⁷ , R ⁰²⁹ , R ⁰³⁰ and R ⁰³¹ are the same or different carbon numbers. 1 to 12 linear, branched or cyclic alkyl group, which may contain a carbonyl group, an ester group or an ether group, or an aryl group having 6 to 12 carbon atoms or an aralkyl having 7 to 20 carbon atoms Represents a group or a thiophenyl group, A ¹ is a single bond, —A ⁰ —C (═O) — O—, —A ⁰ —O— or —A ⁰ —O—C (═O) —, wherein A ⁰ is a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, a carbonyl group, It may contain an ester group or an ether group, A ² is a hydrogen atom, a CF ₃ group or a carbonyl group, Z ¹ is a single bond, a methylene group, an ethylene group, a phenylene group, a fluorinated phenylene group,- O—R ⁰³² —, or —C (═O) —Z ² —R ⁰³² —, wherein Z ² is an oxygen atom or NH, and R ⁰³² is a linear, branched or cyclic alkylene having 1 to 6 carbon atoms. group, a phenylene group, fluorinated phenylene group, phenylene group substituted with a trifluoromethyl group, or an alkenylene group, a carbonyl group, an ester group, which may contain an ether or hydroxyl group .M ^- is Represents a non-nucleophilic counter ion, 0 ≦ b1 ≦ .3,0 ≦ b2 ≦ 0.3,0 ≦ b3 ≦ 0.3,0 <a b1 + b2 + b3 ≦ 0.3.)
[8]
Furthermore, the resist material according to any one of [1] to [7], further comprising any one or more of an organic solvent, a basic compound, a dissolution controller, and a surfactant.
[9]
Including a step of applying the resist material according to any one of [1] to [8] on a substrate, a step of exposing to high energy rays after the heat treatment, and a step of developing using a developer. A characteristic pattern forming method.
[10]
The pattern forming method as described in [9], wherein the high energy ray is a KrF excimer laser having a wavelength of 248 nm, an ArF excimer laser having a wavelength of 193 nm, an electron beam, or a soft X-ray having a wavelength in the range of 3 to 15 nm. .

  The photoresist film formed using the resist material of the present invention can reduce the generation of outgas from the resist film in EUV exposure, and the blob on the resist film after development can be achieved by making the resist film surface hydrophilic. The occurrence of defects can be prevented.

Hereinafter, although embodiment of this invention is described, this invention is not limited to these.
As a result of intensive studies and studies to solve the above problems, the present inventor has found that a normal base that dissolves in an alkali with an acid in order to suppress the generation of outgas from the resist film during exposure in a vacuum in EUV exposure. Invented the use of a resist material blended with a polymer compound having a repeating unit derived from a substituted styrene boronic acid in addition to a polymer. Since the repeating unit derived from the substituted styrene boronic acid is rigid and has a high density, it has the effect of blocking outgas generation from the photoresist film. The repeating unit derived from the substituted styrene boronic acid has high water repellency and can be oriented on the resist film surface after spin coating.

  That is, the present invention relates to a polymer compound containing a repeating unit p derived from a substituted styrene boronic acid as a polymer additive, in particular a polymer compound serving as a base resin whose alkali solubility is improved by an acid, particularly the following general formula ( 1. A resist material comprising the polymer compound represented by 1).

（式中、Ｒ¹は水素原子、炭素数１〜４の直鎖状又は分岐状のアルキル基、又はハロゲン原子である。Ｒ²、Ｒ³は水素原子、炭素数１〜１０の直鎖状、分岐状又は環状のアルキル基、又は炭素数７〜１０のアラルキル基、又はＲ²とＲ³が結合して−Ｏ−Ｂ−Ｏ−と共に環を形成してもよく、この場合、Ｒ²、Ｒ³は炭素数１〜２０の直鎖状、分岐状又は環状を有するアルキレン基、アルケニレン基又はアラルキレン基であり、エーテル基、チオール基又はヒドロキシ基を有していてもよい。０＜ｐ≦１．０である。）

(In the formula, R ¹ is a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a halogen atom. R ² and R ³ are a hydrogen atom and a straight chain having 1 to 10 carbon atoms. , A branched or cyclic alkyl group, an aralkyl group having 7 to 10 carbon atoms, or R ² and R ³ may combine to form a ring with —O—B—O—, in which case R ² , R ³ is a linear, branched or cyclic alkylene group having 1 to 20 carbon atoms, an alkenylene group or an aralkylene group, and may have an ether group, a thiol group or a hydroxy group, 0 <p ≦ 1.0.)

  The photoresist film formed using the resist material to which the polymer compound having the repeating unit p of the general formula (1) is added is derived from the substituted styrene boronic acid on the photoresist film surface represented by the general formula (1). It is characterized by adding a polymer type surfactant having a repeating unit. Polymeric surfactants with repeating units derived from substituted styrene boronic acid are aligned on the surface of the photoresist film after film formation, reducing outgassing from the resist film and reducing pattern defects after development. Can be reduced.

Specific examples of the polymerizable monomer for obtaining a repeating unit derived from the substituted styrene boronic acid represented by p in the general formula (1) can be given below.

Boronic acid strongly associates with the diol compound to form a substituted boronic acid. The substituted boronic acid is hydrolyzed in the aqueous alkali solution by the following reaction formula and becomes alkali-soluble. The hydrolyzed boronic acid having three hydroxyl groups bonded to a boron atom is highly hydrophilic and has a very high alkali dissolution rate.

  Boron has a small absorption in EUV light, and a polymer compound oriented on the resist film surface having boric acid as an alkali-soluble group has a feature that a pattern can be formed without lowering the resist sensitivity. In order to further increase the transparency and reduce the generation of outgas generated from within the resist film, it is preferable to copolymerize with a monomer having an aromatic group containing a large amount of hydrocarbons that are less absorbed by EUV light. The repeating units obtained by copolymerization of aromatic group-containing monomers containing a large amount of hydrocarbons are methacrylates, vinyl ethers, styrenes, vinyl naphthalenes, stilbenes, styryl naphthalenes, dinaphthylethylene in the following general formula (2). , Acenaphthylenes, indenes, benzofurans, and repeating units q1 to q4 based on benzothiophenes.

（式中、Ｒ¹〜Ｒ³は前述と同様である。Ｒ⁴は水素原子又はメチル基、Ｘ¹は単結合、−Ｃ（＝Ｏ）−Ｏ−、又は−Ｏ−であり、Ｘ²、Ｘ³はフェニレン基又はナフチレン基、Ｘ⁴はメチレン基、酸素原子又は硫黄原子である。Ｒ⁵は炭素数６〜２０のアリ−ル基又はアラルキル基で、水酸基、直鎖状、分岐状又は環状のアルキル基又はアルコキシ基、エステル基（−ＯＣＯＲ又は−ＣＯＯＲ：ＲはＣ_1-6のアルキル基）、ケトン基（−ＣＯＲ：ＲはＣ_1-6のアルキル基）、フッ素原子、トリフルオロメチル基、ニトロ基、アミノ基又はシアノ基を有していてもよい。Ｒ⁶、Ｒ⁷、Ｒ⁸、Ｒ⁹は同一又は異種の水素原子、ヒドロキシ基、炭素数１〜１０の直鎖状、分岐状又は環状のアルキル基、アルコキシ基又はアシロキシ基、シアノ基、ニトロ基、アミノ基、ハロゲン原子、エステル基（−ＯＣＯＲ又は−ＣＯＯＲ：ＲはＣ_1-6のアルキル基又はフッ素化アルキル基）、又はカルボキシル基である。ｖは１又は２である。０＜ｐ＜１．０、０≦ｑ１＜１．０、０≦ｑ２＜１．０、０≦ｑ３＜１．０、０≦ｑ４＜１．０、０＜ｑ１＋ｑ２＋ｑ３＋ｑ４＜１．０である。）

(Wherein R ^{1 to} R ³ are the same as described above, R ⁴ is a hydrogen atom or a methyl group, X ¹ is a single bond, —C (═O) —O—, or —O—, and X ² , X ³ is a phenylene group or a naphthylene group, X ⁴ is a methylene group, an oxygen atom or a sulfur atom, R ⁵ is an aryl group or an aralkyl group having 6 to 20 carbon atoms, and is a hydroxyl group, linear or branched Or a cyclic alkyl group or an alkoxy group, an ester group (—OCOR or —COOR: R is a C _1-6 alkyl group), a ketone group (—COR: R is a C _1-6 alkyl group), a fluorine atom, It may have a fluoromethyl group, a nitro group, an amino group or a cyano group, wherein R ⁶ , R ⁷ , R ⁸ and R ⁹ are the same or different hydrogen atoms, hydroxy groups, and straight-chains having 1 to 10 carbon atoms. , Branched or cyclic alkyl group, alkoxy group or acyloxy group, cyano group, nitro group , An amino group, a halogen atom, an ester group (—OCOR or —COOR: R is a C _1-6 alkyl group or a fluorinated alkyl group), or a carboxyl group, v is 1 or 2. 0 <p < 1.0, 0 ≦ q1 <1.0, 0 ≦ q2 <1.0, 0 ≦ q3 <1.0, 0 ≦ q4 <1.0, 0 <q1 + q2 + q3 + q4 <1.0.)

Specific examples of the polymerizable monomer for obtaining the repeating unit q1 copolymerized with styrene having a substituted or unsubstituted boric acid in the general formula (2) are given below.

Specific examples of the monomer for obtaining the repeating unit q2 can be given below.

The monomer for obtaining the repeating unit q3 can be specifically exemplified below.

The monomer for obtaining the repeating unit q4 can be specifically exemplified below.

Here, the ratio of the repeating units p, q1, q2, q3, and q4 is as follows.
p is 0 <p ≦ 1.0, particularly 0 <p <1.0, preferably 0.2 ≦ p <1.0, and more preferably 0.3 ≦ p <1.0.
q is 0 ≦ q1 <1.0, 0 ≦ q2 <1.0, 0 ≦ q3 <1.0, 0 ≦ q4 <1.0, 0 ≦ q1 + q2 + q3 + q4 <1.0, particularly 0 <q1 + q2 + q3 + q4 <1. 0, preferably 0 ≦ q1 ≦ 0.9, 0 ≦ q2 ≦ 0.9, 0 ≦ q3 ≦ 0.9, 0 ≦ q4 ≦ 0.9, 0 <q1 + q2 + q3 + q4 ≦ 0.9, more preferably 0 ≦ q1 ≦ 0.8, 0 ≦ q2 ≦ 0.8, 0 ≦ q3 ≦ 0.8, 0 ≦ q4 ≦ 0.8, 0 <q1 + q2 + q3 + q4 ≦ 0.8.

The base resin used in the resist material of the present invention is required to have a repeating unit having an acid labile group, and as the repeating unit, an acid labile group R ^{11 represented} by the following general formula (3) is used. It is preferably a repeating unit a1 of (meth) acrylic acid ester substituted with or a repeating unit a2 of hydroxystyrene substituted with an acid labile group R ¹³ .

（式中、Ｒ¹⁰、Ｒ¹²はそれぞれ独立に水素原子又はメチル基を表し、Ｒ¹¹、Ｒ¹³は酸不安定基を表す。Ｙ¹は単結合、エステル基，ラクトン環，フェニレン基又はナフチレン基のいずれか１種又は２種以上を有する炭素数１〜１２の連結基、フェニレン基、又はナフチレン基である。Ｙ²は単結合、エステル基、又はアミド基である。０≦ａ１≦０．９、０≦ａ２≦０．９、０＜ａ１＋ａ２＜１．０である。）

(In the formula, R ¹⁰ and R ¹² each independently represent a hydrogen atom or a methyl group, R ¹¹ and R ¹³ each represent an acid labile group. Y ¹ represents a single bond, an ester group, a lactone ring, a phenylene group or a naphthylene. A linking group having 1 to 12 carbon atoms, a phenylene group, or a naphthylene group having any one or more of groups Y ² is a single bond, an ester group, or an amide group, 0 ≦ a1 ≦ 0. .9, 0 ≦ a2 ≦ 0.9, 0 <a1 + a2 <1.0.)

（式中、Ｒ¹⁰、Ｒ¹¹は前述と同様である。） Specific examples of the monomer for obtaining the repeating unit a1 are shown below.

(Wherein R ¹⁰ and R ¹¹ are the same as described above.)

（式中、Ｒ¹²、Ｒ¹³は前述と同様である。） The repeating unit having an acid labile group represented by the repeating unit a2 in the above general formula (3) is a phenolic hydroxyl group, preferably a hydroxyl group of hydroxystyrene or hydroxyphenyl (meth) acrylate substituted with a hydrogen atom. Yes, the monomer for obtaining this can be specifically exemplified below.

(Wherein R ¹² and R ¹³ are the same as described above.)

The acid labile group (acid labile groups of R ¹¹ and R ^{13 in} the general formula (3)) is variously selected and may be the same or different, and in particular, the following general formulas (A-1) to (A And those represented by the group substituted in -3).

In the formula (A-1), R ^L30 is a tertiary alkyl group having 4 to 20 carbon atoms, preferably 4 to 15 carbon atoms, each alkyl group is a trialkylsilyl group having 1 to 6 carbon atoms, and 4 to 20 carbon atoms. An oxoalkyl group or a group represented by the above formula (A-3) is shown. Specific examples of the tertiary alkyl group include a tert-butyl group, a tert-amyl group, a 1,1-diethylpropyl group, and 1-ethylcyclopentyl. Group, 1-butylcyclopentyl group, 1-ethylcyclohexyl group, 1-butylcyclohexyl group, 1-ethyl-2-cyclopentenyl group, 1-ethyl-2-cyclohexenyl group, 2-methyl-2-adamantyl group, etc. Specific examples of the trialkylsilyl group include a trimethylsilyl group, a triethylsilyl group, a dimethyl-tert-butylsilyl group, and the like. Specific examples of the xoalkyl group include a 3-oxocyclohexyl group, a 4-methyl-2-oxooxan-4-yl group, and a 5-methyl-2-oxooxolan-5-yl group. A1 is an integer of 0-6.

In the formula (A-2), R ^L31 and R ^L32 represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, specifically a methyl group, Examples thereof include an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a cyclopentyl group, a cyclohexyl group, a 2-ethylhexyl group, and an n-octyl group. R ^L33 represents a monovalent hydrocarbon group which may have a hetero atom such as an oxygen atom having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, a linear, branched or cyclic alkyl group, Examples include those in which a part of hydrogen atoms are substituted with a hydroxyl group, an alkoxy group, an oxo group, an amino group, an alkylamino group, and the like, and specific examples include the following substituted alkyl groups.

R ^L31 and R ^L32 , R ^L31 and R ^L33 , R ^L32 and R ^L33 may combine to form a ring with the carbon atom to which they are bonded, and in the case of forming a ring, it participates in the formation of the ring. R ^L31 , R ^L32 , and R ^L33 each represent a linear or branched alkylene group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, and preferably the ring has 3 to 10 carbon atoms, particularly 4 to 10 carbon atoms. is there.

  Specific examples of the acid labile group of the above formula (A-1) include tert-butoxycarbonyl group, tert-butoxycarbonylmethyl group, tert-amyloxycarbonyl group, tert-amyloxycarbonylmethyl group, 1,1 -Diethylpropyloxycarbonyl group, 1,1-diethylpropyloxycarbonylmethyl group, 1-ethylcyclopentyloxycarbonyl group, 1-ethylcyclopentyloxycarbonylmethyl group, 1-ethyl-2-cyclopentenyloxycarbonyl group, 1-ethyl Examples include 2-cyclopentenyloxycarbonylmethyl group, 1-ethoxyethoxycarbonylmethyl group, 2-tetrahydropyranyloxycarbonylmethyl group, 2-tetrahydrofuranyloxycarbonylmethyl group and the like.

Furthermore, the substituent shown by following formula (A-1) -1-(A-1) -10 can also be mentioned.

Here, R ^L37 is the same or different from each other, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, R ^L38 is a hydrogen atom, or 1 to 1 carbon atoms. 10 linear, branched or cyclic alkyl groups.
R ^L39 is the same or different from each other, a linear, branched or cyclic alkyl group having 2 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms.
A1 is as described above.

Of the acid labile groups represented by the above formula (A-2), examples of the linear or branched groups include those of the following formulas (A-2) -1 to (A-2) -35. be able to.

  Among the acid labile groups represented by the above formula (A-2), the cyclic ones include tetrahydrofuran-2-yl group, 2-methyltetrahydrofuran-2-yl group, tetrahydropyran-2-yl group, 2- Examples thereof include a methyltetrahydropyran-2-yl group.

Further, the base resin may be intermolecularly or intramolecularly crosslinked by an acid labile group represented by the following formula (A-2a) or (A-2b).

In the formula, R ^L40 and R ^{L41 each} represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms. Alternatively, R ^L40 and R ^L41 may be bonded to form a ring together with the carbon atom to which they are bonded, and when forming a ring, R ^L40 and R ^L41 involved in the formation of the ring have 1 to 8 carbon atoms. A linear or branched alkylene group. R ^L42 is a linear, branched or cyclic alkylene group having 1 to 10 carbon atoms, B1 and D1 are 0 or 1 to 10, preferably 0 or an integer of 1 to 5, and C1 is an integer of 1 to 7. . A represents a (C1 + 1) -valent aliphatic or alicyclic saturated hydrocarbon group having 1 to 50 carbon atoms, an aromatic hydrocarbon group or a heterocyclic group, and these groups may intervene a hetero atom, Alternatively, a part of hydrogen atoms bonded to the carbon atom may be substituted with a hydroxyl group, a carboxyl group, a carbonyl group, or a fluorine atom. B represents —CO—O—, —NHCO—O— or —NHCONH—.
In this case, preferably, A is a divalent to tetravalent C1-20 linear, branched or cyclic alkylene group, an alkyltriyl group, an alkyltetrayl group, or an arylene group having 6 to 30 carbon atoms. In these groups, a hetero atom may be interposed, and a part of hydrogen atoms bonded to the carbon atom may be substituted with a hydroxyl group, a carboxyl group, an acyl group, or a halogen atom. C1 is preferably an integer of 1 to 3.

Specific examples of the crosslinked acetal groups represented by the above formulas (A-2a) and (A-2b) include those represented by the following formulas (A-2) -36 to (A-2) -43.

Next, in the above formula (A-3), R ^L34 , R ^L35 and R ^L36 are monovalent hydrocarbon groups such as linear, branched or cyclic alkyl groups having 1 to 20 carbon atoms, oxygen, sulfur ^May include heteroatoms such as nitrogen, fluorine, R ^L34 and R ^L35 , R ^L34 and R ^L36 , R ^L35 and R ^L36 are bonded to each other, and together with the carbon atom to which they are bonded, they have 3 to 20 carbon atoms A ring may be formed.
As the tertiary alkyl group represented by the formula (A-3), a tert-butyl group, a triethylcarbyl group, a 1-ethylnorbornyl group, a 1-methylcyclohexyl group, a 1-ethylcyclopentyl group, 2- (2- A methyl) adamantyl group, a 2- (2-ethyl) adamantyl group, a tert-amyl group, and the like.
Specific examples of the tertiary alkyl group include the following formulas (A-3) -1 to (A-3) -18.

In the above formulas (A-3) -1 to (A-3) -18, R ^L43 is the same or different linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, or 6 to 20 carbon atoms. An aryl group such as a phenyl group or a naphthyl group. R ^L44 and R ^L46 represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms. R ^L45 represents an aryl group such as a phenyl group having 6 to 20 carbon atoms.

Furthermore, as shown in the following formulas (A-3) -19 and (A-3) -20, a bivalent or higher valent alkylene group and an arylene group R ^L47 are included, and the polymer molecule or between molecules is crosslinked. May be.

In the above formulas (A-3) -19 and (A-3) -20, R ^L43 is the same as described above, and R ^L47 is a linear, branched or cyclic alkylene group having 1 to 20 carbon atoms, or a phenylene group. An arylene group such as an oxygen atom, a sulfur atom, or a nitrogen atom. E1 is an integer of 1 to 3.

（式中、Ｒ¹⁰、ａ１は前述の通り、Ｒ^c3は炭素数１〜８の直鎖状、分岐状又は環状のアルキル基又は炭素数６〜２０の置換されていてもよいアリール基を示す。Ｒ^c4〜Ｒ^c9及びＲ^c12、Ｒ^c13はそれぞれ独立に水素原子又は炭素数１〜１５のヘテロ原子を含んでもよい１価の炭化水素基を示し、Ｒ^c10、Ｒ^c11は水素原子又は炭素数１〜１５のヘテロ原子を含んでもよい１価の炭化水素基を示す。Ｒ^c4とＲ^c5、Ｒ^c6とＲ^c8、Ｒ^c6とＲ^c9、Ｒ^c7とＲ^c9、Ｒ^c7とＲ^c13、Ｒ^c8とＲ^c12、Ｒ^c10とＲ^c11又はＲ^c11とＲ^c12は互いに環を形成していてもよく、その場合には炭素数１〜１５のヘテロ原子を含んでもよい２価の炭化水素基を示す。またＲ^c4とＲ^c13、Ｒ^c10とＲ^c13又はＲ^c6とＲ^c8は隣接する炭素に結合するもの同士で何も介さずに結合し、二重結合を形成してもよい。また、本式により、鏡像体も表す。） In particular, the acid labile group of the formula (A-3) is preferably a repeating unit of a (meth) acrylic acid ester having an exo structure represented by the following formula (A-3) -21.

(In the formula, R ¹⁰ and a1 are as described above, and R ^c3 represents a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms or an optionally substituted aryl group having 6 to 20 carbon atoms. R ^{c4 to} R ^c9 and R ^c12 and R ^c13 each independently represent a hydrogen atom or a monovalent hydrocarbon group that may contain a heteroatom having 1 to 15 carbon atoms, and R ^c10 and R ^c11 represent a hydrogen atom or carbon. 1 represents a monovalent hydrocarbon group which may contain a hetero atom of R 1 to ^15. R ^c4 and R ^c5 , R ^c6 and R ^c8 , R ^c6 and R ^c9 , R ^c7 and R ^c9 , R ^c7 and R ^c13 , R ^c8 and R ^c12 , R ^c10 and R ^c11 or R ^c11 and R ^c12 may form a ring with each other, and in that case, a divalent hydrocarbon group which may contain a hetero atom having 1 to 15 carbon atoms are shown. ^also, a pair of R ^c4 and R ^c13, R ^c10 and R ^c13 or R ^c6 and R ^c8 bind without anything intervening in between those bonded to the adjacent carbon double If may be formed. The formula also represents enantiomer.)

Here, an ester monomer for obtaining a repeating unit having an exo structure represented by the formula (A-3) -21 is disclosed in JP-A No. 2000-327633. Specific examples include the following, but are not limited thereto.

（式中、Ｒ¹⁰、ａ１は前述の通りである。Ｒ^c14、Ｒ^c15はそれぞれ独立に炭素数１〜１０の直鎖状、分岐状又は環状の１価炭化水素基を示す。Ｒ^c14、Ｒ^c15は互いに結合してこれらが結合する炭素原子と共に脂肪族炭化水素環を形成してもよい。Ｒ^c16はフランジイル基、テトラヒドロフランジイル基又はオキサノルボルナンジイル基から選ばれる２価の基を示す。Ｒ^c17は水素原子又はヘテロ原子を含んでもよい炭素数１〜１０の直鎖状、分岐状又は環状の１価炭化水素基を示す。） Next, as the acid labile group represented by the formula (A-3), (meth) acrylic acid having a frangyl group, tetrahydrofurandiyl group or oxanorbornanediyl group represented by the following formula (A-3) -22 Mention may be made of the acid labile groups of the esters.

(In the formula, R ¹⁰ and a 1 are as described above. R ^c14 and R ^c15 each independently represent a linear, branched or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms. R ^c14 , R ^c15 may be bonded to each other to form an aliphatic hydrocarbon ring together with the carbon atom to which they are bonded, and R ^c16 represents a divalent group selected from a ^furandiyl group, a tetrahydrofurandiyl group or an ^{oxanorbornanediyl} group. R ^c17 represents a linear, branched or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may contain a hydrogen atom or a hetero atom.

Monomers for obtaining a repeating unit substituted with an acid labile group having a furandiyl group, a tetrahydrofurandiyl group or an oxanorbornanediyl group are exemplified below. Ac represents an acetyl group and Me represents a methyl group.

  As the polymer compound added to the resist material of the present invention, in addition to the repeating unit having acid labile groups represented by a1 and a2 in the general formula (3), the compatibility with the resist base polymer can be improved. For the purpose of suppressing film loss on the resist surface, hydroxy group, carboxyl group, lactone ring, carbonyl group, carbonate group, ester group, ether group, amide group, sulfonamido group, cyano group, sulfonic acid ester group It is preferable to copolymerize a repeating unit c having an adhesive group such as lactam. In this case, the repeating unit c preferably has a phenolic hydroxyl group that has a sensitizing effect by electron beam and EUV exposure, and the repeating unit having a phenolic hydroxyl group is c1 represented by the following general formula (5). It is preferable to be selected from ˜c9.

（式中、Ｖ¹、Ｖ²、Ｖ⁵は単結合、又は−Ｃ（＝Ｏ）−Ｏ−Ｒ²³−であり、Ｖ³、Ｖ⁴は−Ｃ（＝Ｏ）−Ｏ−Ｒ²⁴−であり、Ｒ²³、Ｒ²⁴は単結合、又は炭素数１〜１０の直鎖状、分岐状又は環状のアルキレン基であり、エーテル基又はエステル基を有していてもよい。Ｒ²²は水素原子、又は炭素数１〜４の直鎖状又は分岐状のアルキル基、アルコキシ基、シアノ基、アルコキシカルボニル基、アシロキシ基又はアシル基であり、Ｒ²¹は同一又は異種の水素原子又はメチル基である。Ｗ¹、Ｗ²はメチレン基又はエチレン基、Ｗ³はメチレン基、酸素原子又は硫黄原子、Ｗ⁴、Ｗ⁵はＣＨ又は窒素原子である。ｓ、ｔは１又は２である。）

(In the formula, V ¹ , V ² and V ⁵ are single bonds or —C (═O) —O—R ²³ —, and V ³ and V ⁴ are —C (═O) —O—R ²⁴ —. R ²³ and R ²⁴ are a single bond or a linear, branched or cyclic alkylene group having 1 to 10 carbon atoms, and may have an ether group or an ester group, and R ²² is hydrogen. An atom, or a linear or branched alkyl group having 1 to 4 carbon atoms, an alkoxy group, a cyano group, an alkoxycarbonyl group, an acyloxy group, or an acyl group, and R ²¹ is the same or different hydrogen atom or methyl group; W ¹ and W ² are a methylene group or an ethylene group, W ³ is a methylene group, an oxygen atom or a sulfur atom, W ⁴ and W ⁵ are CH or a nitrogen atom, and s and t are 1 or 2.)

The monomer for obtaining the repeating units c1 to c9 having the phenolic hydroxyl group can be shown below.

  Further, hydroxy groups other than phenolic hydroxyl groups, lactone rings, ether groups, ester groups, carbonyl groups, cyano groups, sulfonic acid ester groups, sulfonamide groups, cyclic —O—C (═O) —S— or —O. Specific examples of the monomer for obtaining the repeating unit c having an adhesive group selected from —C (═O) —NH— can be given below.

  In the case of a monomer having a hydroxy group, the hydroxy group may be replaced with an acetal that can be easily deprotected with an acid such as an ethoxyethoxy group at the time of polymerization, and may be deprotected with a weak acid and water after the polymerization, Substitution with a formyl group, pivaloyl group or the like, and alkali hydrolysis may be performed after polymerization.

  The polymer compound serving as the base resin of the present invention further comprises a copolymerized repeating unit selected from d1 to d5 derived from indene, acenaphthylene, chromone, coumarin, norbornadiene and derivatives thereof represented by the following general formula (6). It is preferable that

（式中、Ｒ²⁵は同一又は異種の水素原子、それぞれ炭素数１〜３０のアルキル基、一部又は全てがハロゲン原子で置換されたアルキル基、アルコキシ基、アルカノイル基又はアルコキシカルボニル基、炭素数６〜１０のアリール基、ハロゲン原子、又は１，１，１，３，３，３−ヘキサフルオロ−２−プロパノール基である。Ｗ⁶はメチレン基、酸素原子又は硫黄原子である。）

(In the formula, R ²⁵ is the same or different hydrogen atom, an alkyl group having 1 to 30 carbon atoms, an alkyl group partially or entirely substituted with a halogen atom, an alkoxy group, an alkanoyl group or an alkoxycarbonyl group, 6 to 10 aryl groups, halogen atoms, or 1,1,1,3,3,3-hexafluoro-2-propanol groups, W ⁶ is a methylene group, oxygen atom or sulfur atom.)

In this case, the monomers for obtaining indene, acenaphthylene, chromone, coumarin, norbornadiene and their derivatives d1 to d5 can be specifically exemplified below.

Furthermore, the polymer compound serving as the base resin of the present invention can be copolymerized with an onium salt acid generator b having a polymerizable olefin.
JP-A-4-230645, JP-A-2005-84365, and JP-A-2006-45311 propose sulfonium salts and iodonium salts having a polymerizable olefin that generates a specific sulfonic acid. Japanese Patent Application Laid-Open No. 2006-178317 proposes a sulfonium salt in which a sulfonic acid is directly bonded to the main chain.

（式中、Ｒ⁰²⁰、Ｒ⁰²⁴、Ｒ⁰²⁸は水素原子又はメチル基、Ｒ⁰²¹は単結合、フェニレン基、−Ｏ−Ｒ⁰³³−、又は−Ｃ（＝Ｏ）−Ｙ−Ｒ⁰³³−である。Ｙは酸素原子又はＮＨ、Ｒ⁰³³は炭素数１〜６の直鎖状、分岐状又は環状のアルキレン基、アルケニレン基又はフェニレン基であり、カルボニル基（−ＣＯ−）、エステル基（−ＣＯＯ−）、エーテル基（−Ｏ−）又はヒドロキシ基を含んでいてもよい。Ｒ⁰²²、Ｒ⁰²³、Ｒ⁰²⁵、Ｒ⁰²⁶、Ｒ⁰²⁷、Ｒ⁰²⁹、Ｒ⁰³⁰、Ｒ⁰³¹は同一又は異種の炭素数１〜１２の直鎖状、分岐状又は環状のアルキル基であり、カルボニル基、エステル基又はエーテル基を含んでいてもよく、又は炭素数６〜１２のアリール基、炭素数７〜２０のアラルキル基又はチオフェニル基を表す。Ａ¹は単結合、−Ａ⁰−Ｃ（＝Ｏ）−Ｏ−、−Ａ⁰−Ｏ−又は−Ａ⁰−Ｏ−Ｃ（＝Ｏ）−であり、Ａ⁰は炭素数１〜１２の直鎖状、分岐状又は環状のアルキレン基で、カルボニル基、エステル基又はエーテル基を含んでいてもよい。Ａ²は水素原子又はＣＦ₃基又はカルボニル基である。Ｚ¹は単結合、メチレン基、エチレン基、フェニレン基、フッ素化されたフェニレン基、−Ｏ−Ｒ⁰³²−、又は−Ｃ（＝Ｏ）−Ｚ²−Ｒ⁰³²−である。Ｚ²は酸素原子又はＮＨ、Ｒ⁰³²は炭素数１〜６の直鎖状、分岐状又は環状のアルキレン基、フェニレン基、フッ素化されたフェニレン基、トリフルオロメチル基で置換されたフェニレン基、又はアルケニレン基であり、カルボニル基、エステル基、エーテル基又はヒドロキシ基を含んでいてもよい。Ｍ^-は非求核性対向イオンを表す。０≦ｂ１≦０．３、０≦ｂ２≦０．３、０≦ｂ３≦０．３、０≦ｂ１＋ｂ２＋ｂ３≦０．３である。） In the present invention, any repeating unit b1 to b3 having a sulfonium salt represented by the following general formula (4) can be copolymerized.

Wherein R ⁰²⁰ , R ⁰²⁴ and R ⁰²⁸ are a hydrogen atom or a methyl group, R ⁰²¹ is a single bond, a phenylene group, —O—R ⁰³³ —, or —C (═O) —Y—R ⁰³³ —. Y is an oxygen atom or NH, and R ⁰³³ is a linear, branched or cyclic alkylene group, alkenylene group or phenylene group having 1 to 6 carbon atoms, a carbonyl group (—CO—), an ester group (—COO) -), An ether group (-O-) or a hydroxy group, R ⁰²² , R ⁰²³ , R ⁰²⁵ , R ⁰²⁶ , R ⁰²⁷ , R ⁰²⁹ , R ⁰³⁰ and R ⁰³¹ are the same or different carbon numbers. 1 to 12 linear, branched or cyclic alkyl group, which may contain a carbonyl group, an ester group or an ether group, or an aryl group having 6 to 12 carbon atoms or an aralkyl having 7 to 20 carbon atoms Represents a group or a thiophenyl group, A ¹ is a single bond, —A ⁰ —C (═O) — O—, —A ⁰ —O— or —A ⁰ —O—C (═O) —, wherein A ⁰ is a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, a carbonyl group, It may contain an ester group or an ether group, A ² is a hydrogen atom, a CF ₃ group or a carbonyl group, Z ¹ is a single bond, a methylene group, an ethylene group, a phenylene group, a fluorinated phenylene group,- O—R ⁰³² —, or —C (═O) —Z ² —R ⁰³² —, wherein Z ² is an oxygen atom or NH, and R ⁰³² is a linear, branched or cyclic alkylene having 1 to 6 carbon atoms. group, a phenylene group, fluorinated phenylene group, phenylene group substituted with a trifluoromethyl group, or an alkenylene group, a carbonyl group, an ester group, which may contain an ether or hydroxyl group .M ^- is Represents a non-nucleophilic counter ion, 0 ≦ b1 ≦ A .3,0 ≦ b2 ≦ 0.3,0 ≦ b3 ≦ 0.3,0 ≦ b1 + b2 + b3 ≦ 0.3.)

（式中、Ｍ^-は非求核性対向イオンを表す。） The monomer for obtaining the repeating unit b1 which has a sulfonium salt in the said General formula (4) can be specifically illustrated below.

(In the formula, M ⁻ represents a non-nucleophilic counter ion.)

Non-nucleophilic counter ions of M ⁻ include halide ions such as chloride ions and bromide ions, triflate, fluoroalkyl sulfonates such as 1,1,1-trifluoroethanesulfonate, nonafluorobutanesulfonate, tosylate, and benzene. Sulfonate, 4-fluorobenzene sulfonate, aryl sulfonate such as 1,2,3,4,5-pentafluorobenzene sulfonate, alkyl sulfonate such as mesylate and butane sulfonate, bis (trifluoromethylsulfonyl) imide, bis (perfluoroethyl) Mention acid such as imide) such as sulfonyl) imide, bis (perfluorobutylsulfonyl) imide, tris (trifluoromethylsulfonyl) methide, tris (perfluoroethylsulfonyl) methide It can be.

Furthermore, the sulfonate by which the alpha position shown by the following general formula (K-1) was fluoro-substituted, and the sulfonate by which the alpha and beta positions shown by the following general formula (K-2) were fluoro-substituted were mentioned.

In General Formula (K-1), ^R102 represents a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or an aryl having 6 to 20 carbon atoms. Group, which may have an ether group, an ester group, a carbonyl group, a lactone ring, or a fluorine atom.
In general formula (K-2), ^R103 is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms, an acyl group, an alkenyl group having 2 to 20 carbon atoms, or 6 to 20 carbon atoms. An aryl group or an aryloxy group, which may have an ether group, an ester group, a carbonyl group, or a lactone ring.

Specific examples of the monomer for obtaining the repeating unit b2 having the sulfonium salt in the general formula (4) can be given below.

Specific examples of the monomer for obtaining the repeating unit b3 having the sulfonium salt in the general formula (4) can be given below.

  By binding an acid generator to the polymer main chain, acid diffusion can be reduced, and degradation of resolution due to blurring of acid diffusion can be prevented. Further, the edge roughness (LER, LWR) is improved by uniformly dispersing the acid generator.

Here, the ratio of the repeating units a, b, c, and d is as follows.
a is 0 ≦ a1 ≦ 0.9, 0 ≦ a2 ≦ 0.9, 0 <a1 + a2 <1.0, preferably 0 ≦ a1 ≦ 0.8, 0 ≦ a2 ≦ 0.8, 0.1 ≦ a1 + a2. ≦ 0.8, more preferably 0 ≦ a1 ≦ 0.7, 0 ≦ a2 ≦ 0.7, 0.2 ≦ a1 + a2 ≦ 0.7.
b is 0 ≦ b1 ≦ 0.3, 0 ≦ b2 ≦ 0.3, 0 ≦ b3 ≦ 0.3, and 0 ≦ b1 + b2 + b3 ≦ 0.3.
c is 0 ≦ c <1.0, preferably 0 ≦ c ≦ 0.9, more preferably 0 ≦ c ≦ 0.8, and d is 0 ≦ d ≦ 0.5, preferably 0 ≦ d ≦ 0. .4, more preferably 0 ≦ d ≦ 0.3, 0.5 ≦ a1 + a2 + b1 + b2 + b3 + c ≦ 1.0, preferably 0.6 ≦ a1 + a2 + b1 + b2 + b3 + c ≦ 1.0, more preferably 0.7 ≦ a1 + a2 + b1 + b2 + b3 + c ≦ 1.0 And a1 + a2 + b1 + b2 + b3 + c + d = 1.
For example, a + b + c = 1 means that in a polymer compound containing repeating units a, b, and c, the total amount of repeating units a, b, and c is 100 mol% with respect to the total amount of all repeating units. A + b + c <1 means that the total amount of the repeating units a, b and c is less than 100 mol% with respect to the total amount of all the repeating units and has other repeating units in addition to a, b and c. It shows that.

  In order to synthesize a polymer additive represented by the general formula (1) (addition polymer for resist film surface modification) and a base polymer having an acid labile group represented by the general formula (2), one method is as follows. A desired polymer among the monomers giving the repeating units p, q and a to d is subjected to heat polymerization in an organic solvent by adding a radical polymerization initiator, thereby obtaining a copolymeric polymer compound.

  Examples of the organic solvent used at the time of polymerization include toluene, benzene, tetrahydrofuran, diethyl ether, dioxane and the like. As polymerization initiators, 2,2′-azobisisobutyronitrile (AIBN), 2,2′-azobis (2,4-dimethylvaleronitrile), dimethyl 2,2-azobis (2-methylpropionate) ), Benzoyl peroxide, lauroyl peroxide and the like, and preferably polymerized by heating to 50 to 80 ° C. The reaction time is 2 to 100 hours, preferably 5 to 20 hours.

  In the case of copolymerizing hydroxystyrene, there is a method in which acetoxystyrene is used in place of hydroxystyrene, and after polymerization, the acetoxy group is deprotected by alkali hydrolysis to form polyhydroxystyrene.

  Ammonia water, triethylamine, etc. can be used as the base during the alkali hydrolysis. The reaction temperature is −20 to 100 ° C., preferably 0 to 60 ° C., and the reaction time is 0.2 to 100 hours, preferably 0.5 to 20 hours.

The polymer compound used as the polymer additive or base resin in the resist material of the present invention has a weight average molecular weight of 1,000 to 500,000, preferably 2,000 to 30,000. If the weight average molecular weight is too small, the resist material is inferior in heat resistance. If the weight average molecular weight is too large, the alkali solubility is lowered, and a trailing phenomenon is likely to occur after pattern formation.
The weight average molecular weight (Mw) is a measured value in terms of polystyrene using gel permeation chromatography (GPC).

Furthermore, in the high molecular compound used in the positive resist material of the present invention, when the molecular weight distribution (Mw / Mn) of each multi-component copolymer is wide, low molecular weight or high molecular weight polymers exist. Thereafter, foreign matters are seen on the pattern or the shape of the pattern is deteriorated. Therefore, since the influence of such molecular weight and molecular weight distribution tends to increase as the pattern rule becomes finer, in order to obtain a resist material suitably used for fine pattern dimensions, the multi-component copolymer to be used is obtained. The molecular weight distribution is preferably from 1.0 to 2.0, particularly preferably from 1.0 to 1.5 and narrow dispersion.
It is also possible to blend two or more polymers having different resist base polymer composition ratios, molecular weight distributions, and molecular weights.

  The present invention has p, q1, q2, q3, and q4 as repeating units, and orientation on the resist surface after coating reduces the generation of outgas from the resist film and prevents the occurrence of bridge defects and blob defects. Based on a resin blended with an alkali-soluble additive for reducing LWR and a polymer that becomes soluble in an alkaline developer by an acid having a1, a2, b1, b2, b3, c, d as repeating units And The blend ratio of the surface orientation additive is 0.1 to 50 parts by weight, preferably 0.2 to 30 parts by weight, more preferably 0.2 to 0.2 parts by weight with respect to 100 parts by weight of the base polymer containing acid labile groups. 20 parts by mass. The single alkali dissolution rate of the surface orientation additive is in the range of 0.1 to 100,000 nm / s, preferably 1 to 50,000 nm / s, more preferably 10 to 20,000 nm / s.

The positive resist material of the present invention may contain an acid generator for causing the chemically amplified positive resist material used in the pattern forming method of the present invention to function. For example, it generates an acid in response to actinic rays or radiation. May contain a compound (photoacid generator). The component of the photoacid generator may be any compound that generates an acid upon irradiation with high energy rays. Suitable photoacid generators include sulfonium salts, iodonium salts, sulfonyldiazomethane, N-sulfonyloxyimide, oxime-O-sulfonate type acid generators, and the like. These can be used alone or in admixture of two or more.
Specific examples of the acid generator are described in paragraphs [0122] to [0142] of JP-A-2008-111103. In addition, when the high molecular compound which copolymerized the repeating unit b mentioned above is used as base resin, the mixing | blending of an acid generator can be abbreviate | omitted.

The resist material of the present invention can further contain any one or more of an organic solvent, a basic compound, a dissolution controller, a surfactant, and acetylene alcohols.
Specific examples of the organic solvent include ketones such as cyclohexanone, cyclopentanone, and methyl-2-n-amyl ketone described in paragraphs [0144] to [0145] of JP-A-2008-111103, 3-methoxybutanol, Alcohols such as 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether , Ethers such as propylene glycol dimethyl ether and diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, lactic acid Esters such as chill, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, propylene glycol mono tert-butyl ether acetate, γ-butyrolactone, etc. Lactones and mixed solvents thereof, and basic compounds include primary, secondary, and tertiary amine compounds described in paragraphs [0146] to [0164], particularly hydroxy groups, ether groups, ester groups, Examples include amine compounds having a lactone ring, a cyano group, and a sulfonic acid ester group, the surfactants are paragraphs [0165] to [0166], and the dissolution control agent is paragraph [0155] of JP-A-2008-122932. To [0178], and acetylene alcohols are described in paragraph [017 9] to [0182]. A polymer-type quencher described in JP-A-2008-239918 can also be added. This enhances the rectangularity of the patterned resist by being oriented on the coated resist surface. The polymer quencher also has an effect of preventing pattern film loss and pattern top rounding when a protective film for immersion exposure is applied.

  In addition, it is preferable that the compounding quantity of an acid generator shall be 0.01-100 mass parts with respect to 100 mass parts of base resins, especially 0.1-80 mass parts, and the compounding quantity of an organic solvent is 100 mass of base resins. The amount is preferably 50 to 10,000 parts by mass, particularly 100 to 5,000 parts by mass with respect to parts. Moreover, 0-100 mass parts, especially 0-40 mass parts, a basic compound are 0-100 mass parts with respect to 100 mass parts of base resins, especially 0.001-50 mass parts, surfactant is a surfactant. The blending amount is preferably 0 to 10 parts by mass, particularly 0.0001 to 5 parts by mass.

  Various positive resist materials of the present invention, for example, chemically amplified positive resist materials containing an organic solvent, a polymer compound having an acid leaving group represented by the general formula (1), an acid generator, and a basic compound When used for manufacturing an integrated circuit, a known lithography technique can be applied although it is not particularly limited.

For example, the positive resist material of the present invention is applied to a substrate for manufacturing an integrated circuit (Si, SiO ₂ , SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflection film, etc.) or a substrate for manufacturing a mask circuit (Cr , CrO, CrON, MoSi, SiO _2, etc.) by an appropriate coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, etc., the coating film thickness becomes 0.1 to 2.0 μm. Apply as follows. This is pre-baked on a hot plate at 60 to 150 ° C. for 10 seconds to 30 minutes, preferably 80 to 120 ° C. for 30 seconds to 20 minutes. Next, a target pattern is passed through a predetermined mask with a light source selected from high energy rays such as ultraviolet rays, far ultraviolet rays, electron beams, X-rays, excimer lasers, γ rays, synchrotron radiation, and vacuum ultraviolet rays (soft X-rays). Direct exposure is performed. Exposure amount 1 to 200 mJ / cm ² or so, in particular 10 to 100 mJ / cm ^2, or 0.1~100μC / cm ² or so, it is preferable that exposure to particular a 0.5~50μC / cm ^2. Next, post-exposure baking (PEB) is performed on a hot plate at 60 to 150 ° C. for 10 seconds to 30 minutes, preferably 80 to 120 ° C. for 30 seconds to 20 minutes.

  Furthermore, 0.1 to 10% by weight, preferably 2 to 10% by weight, especially 2 to 8% by weight of tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH) 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes, using a developing solution of an alkaline aqueous solution such as tetrabutylammonium hydroxide (TBAH), dip method, paddle method, spray method By developing by a conventional method such as the above, a portion irradiated with light is dissolved in the developer, and a portion not exposed is not dissolved, and a desired positive pattern is formed on the substrate. The resist material of the present invention is particularly suitable for fine patterning using electron beams, vacuum ultraviolet rays (soft X-rays), X-rays, γ rays, and synchrotron radiation among high energy rays.

TEAH, TPAH, and TBAH having a longer alkyl chain than the TMAH aqueous solution that is generally widely used have the effect of reducing the swelling during development and preventing pattern collapse. In Japanese Patent No. 3429592, a repeating unit having an alicyclic structure such as adamantane methacrylate is copolymerized with a repeating unit having an acid labile group such as tert-butyl methacrylate, so that there is no hydrophilic group and water repellency. An example using an aqueous TBAH solution for the development of high polymer is presented.
As the tetramethylammonium hydroxide (TMAH) developer, an aqueous solution of 2.38% by mass is most widely used. This corresponds to 0.26N, and it is preferable that the TEAH, TPAH, and TBAH aqueous solutions have the same normality. The masses of TEAH, TPAH, and TBAH that are 0.26N are 3.84 mass%, 5.31 mass%, and 6.78 mass%, respectively.
In a pattern of 32 nm or less that is resolved by EB or EUV, a phenomenon occurs in which lines are twisted, the lines are stuck together, or the stuck lines are tilted. This is thought to be because the lines swollen and swollen in the developer are stuck together. Since the swollen line is soft like a sponge containing a developer, it tends to collapse due to the stress of rinsing. For this reason, the developer having a long alkyl chain has the effect of preventing swelling and preventing pattern collapse.

  A negative pattern can also be obtained by organic solvent development. As the developer, 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, methyl acetophenone, propyl acetate, butyl acetate, Isobutyl acetate, amyl acetate, butenyl acetate, isoamyl acetate, propyl formate, butyl formate, isobutyl formate, amyl formate, isoamyl formate, methyl valerate, methyl pentenoate, methyl crotonic acid, ethyl crotonic acid, methyl propionate, ethyl propionate , Ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, amyl lactate, isoamyl lactate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, methyl benzoate At least one selected from the group consisting of benzene, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenylacetate, benzyl formate, phenylethyl formate, methyl 3-phenylpropionate, benzyl propionate, ethyl phenylacetate, and 2-phenylethyl acetate Can be mentioned.

At the end of development, rinse is performed. As the rinsing liquid, a solvent which is mixed with the developer and does not dissolve the resist film is preferable. As such a solvent, alcohols having 3 to 10 carbon atoms, ether compounds having 8 to 12 carbon atoms, alkanes having 6 to 12 carbon atoms, alkenes, alkynes, and aromatic solvents are preferably used.
Specifically, as the alkane having 6 to 12 carbon atoms, hexane, heptane, octane, nonane, decane, undecane, dodecane, methylcyclopentane, dimethylcyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, cycloheptane, cyclooctane, And cyclononane. Examples of the alkene having 6 to 12 carbon atoms include hexene, heptene, octene, cyclohexene, methylcyclohexene, dimethylcyclohexene, cycloheptene, and cyclooctene. Examples of the alkyne having 6 to 12 carbon atoms include hexyne, heptin, and octyne. Examples of the alcohol having 3 to 10 carbon atoms include n-propyl alcohol, isopropyl alcohol, 1-butyl alcohol, 2-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, and 3-pentanol. Tert-amyl alcohol, neopentyl alcohol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-methyl-3-pentanol, cyclopentanol, 1-hexanol, 2-hexanol, 3-hexanol 2,3-dimethyl-2-butanol, 3,3-dimethyl-1-butanol, 3,3-dimethyl-2-butanol, 2-ethyl-1-butanol, 2-methyl-1-pentanol, 2- Methyl-2-pentanol, 2-methyl-3-pentanol, 3 Methyl-1-pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol, 4-methyl-1-pentanol, 4-methyl-2-pentanol, 4-methyl-3-pen Examples include butanol, cyclohexanol, and 1-octanol.
Examples of the ether compound having 8 to 12 carbon atoms include di-n-butyl ether, diisobutyl ether, di-sec-butyl ether, di-n-pentyl ether, diisopentyl ether, di-sec-pentyl ether, and di-tert-amyl. One or more kinds of solvents selected from ether and di-n-hexyl ether are exemplified.
In addition to the aforementioned solvents, aromatic solvents such as toluene, xylene, ethylbenzene, isopropylbenzene, tert-butylbenzene, and mesitylene can also be used.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not limited by these description.

(Preparation of polymer compound)
As a polymer compound (polymer additive) added to the resist material, each monomer is combined and subjected to a copolymerization reaction in a methyl ethyl ketone solvent, crystallized in hexane, and further washed with hexane, then isolated and dried. Thus, a polymer compound having the following composition was obtained. The composition of the obtained polymer compound was confirmed by ¹ H-NMR, and the molecular weight and dispersity were confirmed by gel permeation chromatography.

Polymer 1 (Polymer 1)
Molecular weight (Mw) = 7,300
Dispersity (Mw / Mn) = 1.86

Polymer 2
Molecular weight (Mw) = 8,300
Dispersity (Mw / Mn) = 1.86

Polymer 3 (Polymer 3)
Molecular weight (Mw) = 7,900
Dispersity (Mw / Mn) = 1.73

Polymer 4 (Polymer 4)
Molecular weight (Mw) = 8,200
Dispersity (Mw / Mn) = 1.83

Polymer 5 (Polymer 5)
Molecular weight (Mw) = 8,600
Dispersity (Mw / Mn) = 1.75

Polymer 6 (Polymer 6)
Molecular weight (Mw) = 8,000
Dispersity (Mw / Mn) = 1.84

Polymer 7 (Polymer 7)
Molecular weight (Mw) = 6,800
Dispersity (Mw / Mn) = 1.66

Polymer 8 (Polymer 8)
Molecular weight (Mw) = 6,300
Dispersity (Mw / Mn) = 1.69

Polymer 9 (Polymer 9)
Molecular weight (Mw) = 6,200
Dispersity (Mw / Mn) = 1.68

Polymer 10 (Polymer 10)
Molecular weight (Mw) = 6,100
Dispersity (Mw / Mn) = 1.88

Polymer 11 (Polymer 11)
Molecular weight (Mw) = 5,600
Dispersity (Mw / Mn) = 1.96

Polymer 12 (Polymer 12)
Molecular weight (Mw) = 6,100
Dispersity (Mw / Mn) = 1.91

Polymer 13 (Polymer 13)
Molecular weight (Mw) = 6,300
Dispersity (Mw / Mn) = 1.81

Polymer 14 (Polymer 14)
Molecular weight (Mw) = 6,100
Dispersity (Mw / Mn) = 1.91

Polymer 15 (Polymer 15)
Molecular weight (Mw) = 8,500
Dispersity (Mw / Mn) = 1.58

Polymer 16 (Polymer 16)
Molecular weight (Mw) = 7,100
Dispersity (Mw / Mn) = 1.71

Comparative polymer 1 (Reference Polymer 1)
Molecular weight (Mw) = 8,500
Dispersity (Mw / Mn) = 1.77

[Examples and Comparative Examples]
(Preparation of resist material)
EUV evaluation Using the above-mentioned resist film surface modifying polymer compound obtained by ordinary radical polymerization and the following resist polymer, a solution dissolved in the composition shown in Table 1 is filtered through a 0.2 μm size filter. Thus, a positive resist material was prepared.
The obtained positive resist material was applied onto a silicon-containing SOG film SHB-A940 manufactured by Shin-Etsu Chemical Co., Ltd., which was laminated on a Si substrate having a diameter of 4 inches φ with a film thickness of 35 nm. A 35 nm resist film was prepared by pre-baking at 60 ° C. for 60 seconds. EUV exposure using NA0.3, Pseudo PSM, PEB is performed under the temperature conditions shown in Table 2, baked with 0.20N tetrabutylammonium hydroxide (TBAH) aqueous solution for 30 seconds, rinsed with pure water and spin-dried Thus, a resist pattern was formed. The sensitivity for forming the 20 nm line and space, the limit resolution of the minimum dimension resolved at this time, and the edge roughness (LWR) were measured by SEM. The results are shown in Table 2.

ＰＧＭＥＡ：プロピレングリコールモノメチルエーテルアセテート
ＰＧＭＥ：プロピレングリコールモノメチルエーテル
ＦＣ−４４３０：フッ素系界面活性剤、住友３Ｍ社製

PGMEA: Propylene glycol monomethyl ether acetate PGME: Propylene glycol monomethyl ether FC-4430: Fluorosurfactant, manufactured by Sumitomo 3M

Claims (10)

  A resist material comprising: a polymer compound serving as a base resin whose alkali solubility is improved by an acid; and a polymer compound having a repeating unit derived from substituted styrene boronic acid as a polymer additive. The resist material according to claim 1, wherein the polymer compound containing the repeating unit p derived from substituted styrene boronic acid has a repeating unit represented by the following general formula (1).

(In the formula, R ¹ is a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a halogen atom. R ² and R ³ are a hydrogen atom and a straight chain having 1 to 10 carbon atoms. , A branched or cyclic alkyl group, an aralkyl group having 7 to 10 carbon atoms, or R ² and R ³ may combine to form a ring with —O—B—O—, in which case R ² , R ³ is a linear, branched or cyclic alkylene group having 1 to 20 carbon atoms, an alkenylene group or an aralkylene group, and may have an ether group, a thiol group or a hydroxy group, 0 <p ≦ 1.0.) The polymer compound containing the repeating unit p derived from substituted styrene boronic acid is further derived from one or more monomers selected from repeating units q1 to q4 represented by the following general formula (2) in addition to the repeating unit p. The resist material according to claim 2, wherein units are copolymerized.

(Wherein R ^{1 to} R ³ are the same as described above, R ⁴ is a hydrogen atom or a methyl group, X ¹ is a single bond, —C (═O) —O—, or —O—, and X ² , X ³ is a phenylene group or a naphthylene group, X ⁴ is a methylene group, an oxygen atom or a sulfur atom, R ⁵ is an aryl group or an aralkyl group having 6 to 20 carbon atoms, and is a hydroxyl group, linear or branched Or a cyclic alkyl group or an alkoxy group, an ester group (—OCOR or —COOR: R is a C _1-6 alkyl group), a ketone group (—COR: R is a C _1-6 alkyl group), a fluorine atom, It may have a fluoromethyl group, a nitro group, an amino group or a cyano group, wherein R ⁶ , R ⁷ , R ⁸ and R ⁹ are the same or different hydrogen atoms, hydroxy groups, and straight-chains having 1 to 10 carbon atoms. , Branched or cyclic alkyl group, alkoxy group or acyloxy group, cyano group, nitro group , An amino group, a halogen atom, an ester group (—OCOR or —COOR: R is a C _1-6 alkyl group or a fluorinated alkyl group), or a carboxyl group, v is 1 or 2. 0 <p < 1.0, 0 ≦ q1 <1.0, 0 ≦ q2 <1.0, 0 ≦ q3 <1.0, 0 ≦ q4 <1.0, 0 <q1 + q2 + q3 + q4 <1.0.)   The resist material according to claim 1, wherein the resist material is a chemically amplified positive resist material.   5. The resist according to claim 4, wherein the polymer compound as the base resin includes a repeating unit having an acid labile group and a repeating unit having a hydroxy group and / or an adhesive group of a lactone ring. material. In the polymer compound as the base resin, the repeating unit having an acid labile group is represented by the following general formula (3) in which a hydrogen atom of a hydroxyl group of a carboxyl group and / or a phenol group is substituted with an acid labile group. 6. The resist material according to claim 5, wherein the resist material is one or more repeating units selected from repeating units a1 and a2 and the polymer compound has a weight average molecular weight in the range of 1,000 to 500,000. .

(In the formula, R ¹⁰ and R ¹² each independently represent a hydrogen atom or a methyl group, R ¹¹ and R ¹³ each represent an acid labile group. Y ¹ represents a single bond, an ester group, a lactone ring, a phenylene group or a naphthylene. A linking group having 1 to 12 carbon atoms, a phenylene group, or a naphthylene group having any one or more of groups Y ² is a single bond, an ester group, or an amide group, 0 ≦ a1 ≦ 0. .9, 0 ≦ a2 ≦ 0.9, 0 <a1 + a2 <1.0.) In addition to the repeating unit a1 or a2 represented by the general formula (3) in which the polymer compound as the base resin is substituted with an acid labile group, a hydrogen atom of a hydroxyl group of a carboxyl group and / or a phenol group, It is a polymer compound having a weight average molecular weight in the range of 1,000 to 500,000 obtained by copolymerizing one or more repeating units selected from sulfonium salts b1 to b3 represented by the following general formula (4). The resist material according to claim 6.

Wherein R ⁰²⁰ , R ⁰²⁴ and R ⁰²⁸ are a hydrogen atom or a methyl group, R ⁰²¹ is a single bond, a phenylene group, —O—R ⁰³³ —, or —C (═O) —Y—R ⁰³³ —. Y is an oxygen atom or NH, and R ⁰³³ is a linear, branched or cyclic alkylene group, alkenylene group or phenylene group having 1 to 6 carbon atoms, a carbonyl group (—CO—), an ester group (—COO) -), An ether group (-O-) or a hydroxy group, R ⁰²² , R ⁰²³ , R ⁰²⁵ , R ⁰²⁶ , R ⁰²⁷ , R ⁰²⁹ , R ⁰³⁰ and R ⁰³¹ are the same or different carbon numbers. 1 to 12 linear, branched or cyclic alkyl group, which may contain a carbonyl group, an ester group or an ether group, or an aryl group having 6 to 12 carbon atoms or an aralkyl having 7 to 20 carbon atoms Represents a group or a thiophenyl group, A ¹ is a single bond, —A ⁰ —C (═O) — O—, —A ⁰ —O— or —A ⁰ —O—C (═O) —, wherein A ⁰ is a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, a carbonyl group, It may contain an ester group or an ether group, A ² is a hydrogen atom, a CF ₃ group or a carbonyl group, Z ¹ is a single bond, a methylene group, an ethylene group, a phenylene group, a fluorinated phenylene group,- O—R ⁰³² —, or —C (═O) —Z ² —R ⁰³² —, wherein Z ² is an oxygen atom or NH, and R ⁰³² is a linear, branched or cyclic alkylene having 1 to 6 carbon atoms. group, a phenylene group, fluorinated phenylene group, phenylene group substituted with a trifluoromethyl group, or an alkenylene group, a carbonyl group, an ester group, which may contain an ether or hydroxyl group .M ^- is Represents a non-nucleophilic counter ion, 0 ≦ b1 ≦ .3,0 ≦ b2 ≦ 0.3,0 ≦ b3 ≦ 0.3,0 <a b1 + b2 + b3 ≦ 0.3.)   The resist material according to any one of claims 1 to 7, further comprising at least one of an organic solvent, a basic compound, a dissolution controller, and a surfactant.   It includes a step of applying the resist material according to any one of claims 1 to 8 on a substrate, a step of exposing to high energy rays after heat treatment, and a step of developing using a developer. A characteristic pattern forming method.   The pattern forming method according to claim 9, wherein the high energy beam is a KrF excimer laser having a wavelength of 248 nm, an ArF excimer laser having a wavelength of 193 nm, an electron beam, or a soft X-ray having a wavelength of 3 to 15 nm. .