JP5398966B2 - Polymer compound, positive resist material, and pattern forming method using the same - Google Patents

Description

  The present invention relates to a polymer compound suitable as a base resin for a positive resist material, particularly a chemically amplified positive resist material, a positive resist material using the same, and a pattern forming method.

  With the high integration and high speed of LSI, pattern rule miniaturization is progressing rapidly. Mass production of 180 nm rule devices on the SIA roadmap was supposed to be 2001 in 1994, but it was actually two years ahead of schedule and mass production started in 1999. ArF (193 nm) lithography was the main focus for 180 nm devices, but KrF (248 nm) lithography has been extended, and mass production with 150 nm generation and even 130 nm is being studied with KrF lithography.

With the maturation of KrF lithography, acceleration of miniaturization is accelerating. ArF is expected to be finely processed at 90 nm, and F ₂ (157 nm) is expected to be 65 nm, but beyond that, EB reduced projection exposure (PREVAIL, SCALPEL) and EUV using soft X-ray as a light source are candidates. Raise.

Conventionally, the resist polymer has changed greatly each time the wavelength of light changes. This is to ensure the necessary transmittance. For example, in the transition from g-line to i-line, the base of the photosensitizer changed from benzophenone to non-benzophenone type. The transition from i-line to KrF was accompanied by a change from a novolak resin that had been used for a long time to a hydroxystyrene system. The transition from KrF to ArF is dramatic, and a polymer having a double bond does not transmit light at all, so that it is changed to an alicyclic polymer. Further, in F ₂ , an alicyclic polymer into which a fluorine atom is introduced such as a fluororesin has been studied for further improving the transmittance.

  Light elements such as hydrocarbons used in resists for high energy rays with very short wavelengths such as EB and X-rays hardly absorb, and polyhydroxystyrene-based resist materials have been studied.

  The EB resist has been practically used for mask drawing. In recent years, mask manufacturing techniques have become a problem. A reduction projection exposure apparatus has been used since the era of g-line, and its reduction magnification has been 1/5. Recently, as the chip size has increased and the projection lens has become larger, the 1/4 magnification has been reduced. It has come to be used. Not only reducing the line width due to the progress of microfabrication, but also reducing the line width by changing the magnification is a big problem for the mask manufacturing technique.

  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 becomes possible by increasing the acceleration voltage in the electron gun of EB, 10 keV to 30 keV, and recently 50 keV is becoming mainstream.

  Here, as the acceleration voltage increases, lowering the sensitivity of the resist 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 decreases. Since the mask exposure machine exposes by direct drawing with a single stroke, lowering the sensitivity of the resist leads to lower productivity, which is not preferable. Due to the demand for higher sensitivity, chemically amplified resists have been studied.

Thus, by improving the accelerating voltage and applying a high-contrast chemically amplified resist, a dimension of 500 nm of 125 nm on the wafer can be accurately drawn with a 1/4 reduction. However, KrF extends the device size to 130 nm, ArF is said to be applied from 90 nm, and F ₂ is predicted to be 65 nm. The limit of optical lithography with F ₂ is predicted to be 50 nm. At this time, the dimension on the mask is 200 nm. At present, dimensional control of 200 nm is difficult only by improving the resolution of the resist. In the case of optical lithography, the thinning of the resist greatly contributes to the improvement of 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. The only way to reduce the film thickness is to improve the dry etching resistance of the resist.

Here, it is generally said that there is a correlation between the carbon density of the resist and the dry etching resistance. For EB writing that is not affected by absorption, a resist based on a novolak polymer having excellent etching resistance has been developed. However, novolak polymers are difficult to control the molecular weight and dispersibility, and are considered not suitable materials for microfabrication.
Further, it has been reported that the absorption of carbon atoms is small in soft X-ray (EUV) exposure at a wavelength of 5 to 20 nm, which is expected as an exposure method in fine processing of 70 nm or later along with F ₂ exposure. It has been found that 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 (see Non-Patent Document 1).

  Thus, a resist material having a high carbon density, high dry etching resistance, and high resolution has been demanded.

N. Matsuzawa et. al. Jp. J. et al. Appl. Phys. Vol. 38 p7109-7113 (1999)

  The present invention has been made in view of such problems, and has a higher resolution than conventional positive resist materials, a good pattern shape after exposure, and a further excellent etching resistance. It is an object of the present invention to provide a polymer compound suitable as a base resin for a material, particularly a chemically amplified positive resist material, a positive resist material using the same, and a pattern forming method.

（式中、Ｒ¹、Ｒ^３は独立して水素原子又はメチル基であり、Ｒ²、Ｒ^４は独立して水素原子、アセチル基、アルキル基、酸不安定基のいずれかであり、Ｒ²、Ｒ^４のどちらか一方あるいは両方が酸不安定基である。ｐ、ｑは１又は２である。ａ、ｂは、０＜ａ／（ａ＋ｂ）≦０．９０、０．１≦ｂ／（ａ＋ｂ）＜１の範囲である。） The present invention has been made in order to solve the above-described problems, and has at least a repeating unit of substituted hydroxystyrene represented by the following general formula (1) and a repeating unit of substituted hydroxyvinylnaphthalene. that provides a polymer compound.

(Wherein R ¹ and R ³ are each independently a hydrogen atom or a methyl group, R ² and R ⁴ are each independently a hydrogen atom, an acetyl group, an alkyl group or an acid labile group; ² and / or R ⁴ is an acid labile group, p and q are 1 or 2. a and b are 0 <a / (a + b) ≦ 0.90, 0.1 ≦ b / (A + b) <1 range.)

（式中、Ｒ^２１、Ｒ^２２は独立して水素原子、炭素数１〜６の直鎖状、分岐状、環状のアルキル基のいずれかであり、Ｘ^１は炭素数４〜１２の環状のアルキル基であり、有橋環式のアルキル基であっても良い。） In this case, it is not preferable that the acid labile group represented by the following general formula (1) -1.

(Wherein R ²¹ and R ²² are each independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, and X ¹ is a cyclic group having 4 to 12 carbon atoms. (It is an alkyl group and may be a bridged cyclic alkyl group.)

In this case, it is not preferable weight-average molecular weight of the polymeric compound is in the range of 1,000 to 500,000.

The present invention, that provides a positive resist material, characterized in that comprising the polymer compound as a base resin.

  The polymer compound can be suitably used as a base resin for a positive resist material. The positive resist material containing the polymer compound as a base resin has a significantly high alkali dissolution rate contrast before and after exposure, high sensitivity and high resolution, exposure margin, and excellent process adaptability. The pattern shape after the exposure is good, and the dimensional difference between the dense pattern and the sparse pattern is particularly small, and the etching resistance is more excellent. Further, the polymer compound in which the acid labile group is represented by the general formula (1) -1 has higher etching resistance. Because of these excellent characteristics, the practicality is extremely high and it is very effective as a resist material for VLSI and a mask pattern forming material.

  Further, if the mass average molecular weight of the polymer compound is in the range of 1,000 to 500,000, the resist material has sufficient heat resistance and alkali solubility, and there is little possibility of causing tailing after pattern formation. .

In this case, the positive resist material, it is not preferable is a chemical amplified resist material containing an acid generator.

  As described above, when the positive resist material is a chemically amplified resist material containing an acid generator, an extremely high-accuracy pattern can be obtained by an acid catalyst reaction.

In this case, the positive resist material, an organic solvent, a basic compound, a dissolution inhibitor, it is not preferable are those containing any one or more surfactants.

  Thus, by further blending an organic solvent, for example, the coating property of a resist material on a substrate can be improved, and by blending a basic compound, the diffusion rate of acid in the resist film By adding a dissolution inhibitor, the difference in dissolution rate between the exposed and unexposed areas can be further increased, and the resolution can be further improved. In addition, the coating property of the resist material can be further improved or controlled by adding a surfactant.

Such a positive resist material of the present invention includes at least a step of applying the positive resist material on a substrate, a step of exposing to high energy rays after heat treatment, and a step of developing using a developer. by performing, Ru can be used as a method for forming a pattern on a semiconductor substrate or a mask substrate.

  Needless to say, development may be performed after the post-exposure heat treatment, and various other processes such as an etching process, a resist removal process, and a cleaning process may be performed.

  As described above, the positive resist material of the present invention has a significantly high alkali dissolution rate contrast before and after exposure, high sensitivity and high resolution, good pattern shape after exposure, and particularly It suppresses the acid diffusion rate and exhibits excellent etching resistance. Accordingly, a positive resist material, particularly a chemically amplified positive resist material, which is particularly suitable as a material for forming a fine pattern for VLSI manufacturing or a photomask can be obtained. Such a positive resist material can be suitably used not only for lithography in semiconductor circuit formation, but also for mask circuit pattern formation, micromachine, thin film magnetic head circuit formation, and the like.

  Hereinafter, although embodiment of this invention is described, this invention is not limited to these.

  As a result of intensive studies to obtain a positive resist material having high sensitivity and high resolution, exposure margin, etc. that have been recently requested, good etching shape, and excellent etching resistance, For this, a polymer obtained by copolymerizing at least one hydroxy group with an acid labile group and copolymerizing substituted hydroxyvinylnaphthalene and substituted hydroxystyrene is used as a positive resist material, particularly a chemically amplified positive resist. It has been found that it is extremely effective when used as a base resin of a material, and the present invention has been completed.

  That is, the present inventors first considered increasing the carbon density of the resist in order to improve the etching resistance. The naphthalene ring is 94% with respect to the carbon density of 92% of the benzene ring, and the material containing the naphthalene ring is expected to have improved dry etching resistance. Originally, the naphthalene ring has been not attracting much attention because of its high light absorption, but it was considered to be a promising material for ultrashort wavelength exposure without the influence of absorption.

  Therefore, the present inventors examined the copolymerization of hydroxyvinylnaphthalene. When hydroxypolyvinylnaphthalene is used as a resist material, not only the etching resistance is improved, but also the dissolution contrast is high and the diffusion size difference can be reduced by suppressing acid diffusion, and the effect is replaced by an acid labile group. More than hydroxystyrene. This is presumably because hydroxyvinylnaphthalene is a condensed hydrocarbon, and the bonding portion becomes rigid due to the hydroxy group of the polymer, thereby suppressing thermal movement in the molecule and suppressing acid diffusion.

  From the above, the present inventors further reduced the acid diffusion and improved the dissolution contrast and etching resistance, and hydroxystyrene, hydroxyvinylnaphthalene in which at least one hydroxy group is substituted with an acid labile group, By using a polymer obtained by copolymerization as a base resin for positive resist materials, especially chemically amplified positive resist materials, the alkali dissolution rate contrast before and after exposure is significantly high, and it has high sensitivity and high resolution. In addition, a positive resist material, particularly a chemically amplified positive resist material, which has a good pattern shape after exposure and exhibits excellent etching resistance, and is particularly suitable for ultra-LSI manufacturing or as a photomask fine pattern forming material is obtained. It has been found that.

（式中、Ｒ¹、Ｒ^３は独立して水素原子又はメチル基であり、Ｒ²、Ｒ^４は独立して水素原子、アセチル基、アルキル基、酸不安定基のいずれかであり、Ｒ²、Ｒ^４のどちらか一方あるいは両方が酸不安定基である。ｐ、ｑは１又は２である。ａ、ｂは、０＜ａ／（ａ＋ｂ）≦０．９０、０．１≦ｂ／（ａ＋ｂ）＜１の範囲である。） That is, the polymer compound according to the present invention is characterized by having at least a repeating unit of substituted hydroxystyrene represented by the following general formula (1) and a repeating unit of substituted hydroxyvinylnaphthalene.

(Wherein R ¹ and R ³ are each independently a hydrogen atom or a methyl group, R ² and R ⁴ are each independently a hydrogen atom, an acetyl group, an alkyl group or an acid labile group; ² and / or R ⁴ is an acid labile group, p and q are 1 or 2. a and b are 0 <a / (a + b) ≦ 0.90, 0.1 ≦ b / (A + b) <1 range.)

  A positive resist material containing such a high molecular compound as a base resin has a particularly high resist film dissolution contrast, high sensitivity, high resolution, exposure margin, excellent process adaptability, The pattern shape after the exposure is good, and the dimensional difference between the dense pattern and the sparse pattern is particularly small, and the etching resistance is more excellent. Therefore, since it has these excellent characteristics, it is very practical and is very effective as a resist material for VLSI and a mask pattern forming material.

As the alkyl group of R ² and R ^{4 in} the general formula (1), a straight chain such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group or the like A branched alkyl group is exemplified.

  The polymer compound of the present invention must have the repeating unit a of the substituted hydroxystyrene and the repeating unit b of the substituted hydroxyvinylnaphthalene, but is substituted with an acid labile group represented by the following general formula (2). It is also possible to additionally copolymerize the repeating unit c of the (meth) acrylic acid ester.

(In the formula, R ⁵ represents a hydrogen atom or a methyl group, and R ⁶ is an acid labile group. The range is 0 ≦ c / (a + b + c) ≦ 0.7.)

  In addition to the above repeating units a, b and c, the repeating units that can be copolymerized with the polymer compound of the present invention include styrene, indene, hydroxyindene, vinylnaphthalene, vinylanthracene, vinylpyrene, indole, acenaphthylene, norbornadiene, norbornene, tricyclo Decene, tetracyclododecene, methyleneindane, chromone, coumarone, (meth) acrylates having lactone, (meth) acrylic acid, 3-hydroxyadamantane (meth) acrylic acid ester, maleic anhydride, itaconic anhydride, maleimides And vinyl ethers.

  Furthermore, the polymer compound of the present invention can be copolymerized with a repeating unit having a sulfonium salt represented by the following general formula (3).

(Wherein R ⁷ is a hydrogen atom or a methyl group, R ⁸ is a phenylene group, —O—R ¹¹ —, or —C (═O) —Y—R ¹¹ —. Y is an oxygen atom or NH, R ¹¹ represents a linear 1 to 6 carbon atoms, branched or cyclic alkylene group, a phenylene group or alkenylene group, a carbonyl group, an ester group, which may contain an ether or hydroxyl group .R ^9, R ¹⁰ is the same or different linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, which may contain a carbonyl group, an ester group or an ether group, or an aryl group having 6 to 12 carbon atoms. Represents an aralkyl group having 7 to 20 carbon atoms or a thiophenyl group, and X ⁻ represents a non-nucleophilic counter ion.)

Acid labile groups in the above general formulas (1) and (2) (R ^{2 in} the above general formula (1), acid labile groups in which hydrogen atoms of the hydroxy group of R ⁴ are substituted, R in the above general formula (2) ^The acid labile group substituted with the hydrogen atom of the hydroxyl group of the carboxyl group ⁶ is selected variously, but may be the same or different, and in particular, the following formulas (A-1) to (A-3) may be mentioned: .

In the formula (A-1), R ³⁰ 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 general 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-ethyl. Cyclopentyl 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. Specifically oxoalkyl group, 3-oxo-cyclohexyl group, 4-methyl-2-oxooxan-4-yl group, and 5-methyl-2-oxooxolan-5-yl group. a1 is an integer of 0-6.

In the formula (A-2), R ³¹ and R ³² 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 ³³ 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 ³¹ and R ³² , R ³¹ and R ³³ , and R ³² and R ³³ may combine to form a ring together with the carbon atoms to which they are bonded, and in the case of forming a ring, R ³¹ , R ³² , R ³³ represents 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.

  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. In the following formula, a1 is the same as above.

Here, R ³⁷ 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 ³⁸ is a hydrogen atom, or 1 to 1 carbon atoms. 10 linear, branched or cyclic alkyl groups.
R ³⁹ is a linear, branched or cyclic alkyl group having 2 to 10 carbon atoms that is the same or different from each other, or an aryl group having 6 to 20 carbon atoms.

  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.

（式中、Ｒ^２１、Ｒ^２２は独立して水素原子、炭素数１〜６の直鎖状、分岐状、環状のアルキル基のいずれかであり、Ｘ^１は炭素数４〜１２の環状のアルキル基であり、有橋環式のアルキル基であっても良い。） Among the acid labile groups represented by the above formula (A-2), the acid labile groups represented by the following general formula (1) -1 include the following (A-2) -1 ′ to (A-2): -19 '.

(Wherein R ²¹ and R ²² are each independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, and X ¹ is a cyclic group having 4 to 12 carbon atoms. (It is an alkyl group and may be a bridged cyclic alkyl group.)

  If the acid labile group in the general formula (1) is represented by the general formula (1) -1, the carbon density is increased. Therefore, a polymer compound having a repeating unit of the general formula (1) is used. A resist formed using a resist material included as a base resin is preferable because it has a higher carbon density and further has excellent dry etching resistance.

  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 general formula (A-2a) or (A-2b).

In the formula, R ⁴⁰ and R ⁴¹ represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms. Alternatively, R ⁴⁰ and R ⁴¹ may be bonded to form a ring together with the carbon atom to which they are bonded. When forming a ring, R ⁴⁰ and R ⁴¹ are linear or branched having 1 to 8 carbon atoms. -Like alkylene group. R ⁴² is a straight-chain having 1 to 10 carbon atoms, branched or cyclic alkylene group, b1, d1 is 0 or 1 to 10, preferably 0 or an integer of 1 to 5, c1 is an integer of 1-7 . 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 general formulas (A-2a) and (A-2b) include those represented by the following formulas (A-2) -37 to (A-2) -44.

Next, in the formula (A-3), R ³⁴ , R ³⁵ and R ³⁶ are monovalent hydrocarbon groups such as a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, oxygen, sulfur, Hetero atoms such as nitrogen and fluorine may be contained, and R ³⁴ and R ³⁵ , R ³⁴ and R ³⁶ , R ³⁵ and R ³⁶ are bonded to each other, and a ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. 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 formulas (A-3) -1 to (A-3) -18, R ⁴³ is the same or different, linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, or having 6 to 20 carbon atoms. An aryl group such as a phenyl group is shown. R ⁴⁴ and R ⁴⁶ represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms. R ⁴⁵ 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 divalent or higher valent alkylene group and an arylene group, R ^47, are contained, and the polymer molecule or between molecules is crosslinked. May be.

In formulas (A-3) -19 and (A-3) -20, R ⁴³ is the same as described above, and R ⁴⁷ is a linear, branched or cyclic alkylene group having 1 to 20 carbon atoms, a phenylene group, or the like. And may contain a hetero atom such as an oxygen atom, a sulfur atom or a nitrogen atom. e1 is an integer of 1 to 3.

R ³⁰ , R ³³ , and R ³⁶ in formulas (A-1), (A-2), and (A-3) are a phenyl group, a p-methylphenyl group, a p-ethylphenyl group, and a p-methoxyphenyl group. An unsubstituted or substituted aryl group such as an alkoxy-substituted phenyl group, an aralkyl group such as a benzyl group or a phenethyl group, or a hydrogen atom having an oxygen atom in these groups or bonded to a carbon atom is substituted with a hydroxyl group Examples thereof include an alkyl group represented by the following formula in which two hydrogen atoms are substituted with an oxygen atom to form a carbonyl group, or an oxoalkyl group.

  In particular, the acid labile group (A-3) is preferably a repeating unit of (meth) acrylic acid ester having an exo structure shown by A-3-21 below.

(.R shown wherein, R ⁵ is as defined above, R ^c3 represents a linear 1 to 8 carbon atoms, branched or cyclic alkyl or optionally substituted aryl group having 6 to 20 carbon atoms ^c4 to R ^c9 and ^{R c12, R c13} each independently represent also be monovalent to contain hydrogen atoms or a hetero atom number of 1 to 15 carbon hydrocarbon radicals, ^{R c10, R c11} is a hydrogen atom. Alternatively 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 are A divalent hydrocarbon group which may form a ring and may contain a hetero atom having 1 to 15 carbon atoms, R ^c4 and R ^c13 , R ^c10 and R ^c13 or R ^c6 ; R ^c8 may be bonded to adjacent carbons without any intervening bonds to form a double bond. In addition, this formula also represents a mirror image.)

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

  Next, examples of the acid labile group shown in (A-3) include the acid labile group of (meth) acrylic acid ester having frangiyl, tetrahydrofurandiyl or oxanorbornanediyl shown in A-3-22 below. I can do it.

(In the formula, R ⁵ is 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, or 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 ^flangedyl , tetrahydrofurandiyl or ^{oxanorbornanediyl} . 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 repeating units substituted with acid labile groups having frangyl, tetrahydrofuraniyl or oxanorbornanediyl are exemplified below.

上記式中、Ｍｅはメチル基を、Ａｃはアセチル基を示す。

In the above formula, Me represents a methyl group, and Ac represents an acetyl group.

  Examples of the trialkylsilyl group having 1 to 6 carbon atoms as the acid labile group include a trimethylsilyl group, a triethylsilyl group, and a tert-butyldimethylsilyl group.

  In order to synthesize the polymer compound according to the present invention, one method is radical polymerization of hydroxystyrene represented by the following formula (1a) and hydroxyvinylnaphthalene represented by the following formula (2b) in an organic solvent. A polymerization polymer compound can be obtained by adding an initiator and performing heat polymerization.

（式中、Ｒ¹〜Ｒ^４、ｐ、ｑは上記の通りである。）

(In the formula, R ^{1 to} R ⁴ , p and q are as described above.)

  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.

  There is also a method of using acetoxyvinylnaphthalene instead of hydroxyvinylnaphthalene and deprotecting the acetoxy group by alkali hydrolysis after polymerization to give hydroxypolyvinylnaphthalene.

  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.

  After isolating the obtained polymer compound, an acid labile group is introduced by replacing the hydrogen atom of the phenolic hydroxyl group of the repeating unit of hydroxystyrene and the repeating unit of hydroxyvinylnaphthalene with an acetyl group, an alkyl group or the like. be able to. For example, it is possible to obtain a polymer compound in which the phenolic hydroxyl group is partially protected with an alkoxyalkyl group by reacting the phenolic hydroxyl group of the polymer compound with an alkenyl ether compound in the presence of an acid catalyst.

  At this time, the reaction solvent is preferably an aprotic polar solvent such as dimethylformamide, dimethylacetamide, tetrahydrofuran or ethyl acetate, and may be used alone or in combination. As the acid of the catalyst, hydrochloric acid, sulfuric acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, methanesulfonic acid, p-toluenesulfonic acid pyridinium salt and the like are preferable, and the amount used thereof is the phenolic hydroxyl group of the polymer compound to be reacted. It is preferable that it is 0.1-10 mol% with respect to 1 mol of all the hydroxyl groups. 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.

  It is also possible to obtain a polymer compound in which a phenolic hydroxyl group is partially protected with an alkoxyalkyl group by reacting with a polymer compound in the presence of a base using a halogenated alkyl ether compound.

  At this time, the reaction solvent is preferably an aprotic polar solvent such as acetonitrile, acetone, dimethylformamide, dimethylacetamide, tetrahydrofuran, or dimethylsulfoxide, and may be used alone or in combination. As the base, triethylamine, pyridine, diisopropylamine, potassium carbonate and the like are preferable, and the amount used is preferably 10 mol% or more with respect to 1 mol of all hydroxyl groups of the phenolic hydroxyl group of the polymer compound to be reacted. The reaction temperature is −50 to 100 ° C., preferably 0 to 60 ° C., and the reaction time is 0.5 to 100 hours, preferably 1 to 20 hours.

  Furthermore, an acid labile group can be introduced by reacting a dialkyl dicarbonate compound or an alkoxycarbonylalkyl halide with a polymer compound in a solvent in the presence of a base.

  At this time, the reaction solvent is preferably an aprotic polar solvent such as acetonitrile, acetone, dimethylformamide, dimethylacetamide, tetrahydrofuran, or dimethylsulfoxide, and may be used alone or in combination. As the base, triethylamine, pyridine, imidazole, diisopropylamine, potassium carbonate and the like are preferable, and the amount used is preferably 10 mol% or more based on 1 mol of all hydroxyl groups of the phenolic hydroxyl group of the original polymer compound. . The reaction temperature is 0 to 100 ° C, preferably 0 to 60 ° C. The reaction time is 0.2 to 100 hours, preferably 1 to 10 hours.

Examples of the dialkyl dicarbonate compound include di-tert-butyl dicarbonate and di-tert-amyl dicarbonate. Examples of the alkoxycarbonylalkyl halide include tert-butoxycarbonylmethyl chloride, tert-amyloxycarbonylmethyl chloride, and tert-butoxy. Examples thereof include carbonylmethyl bromide and tert-butoxycarbonylethyl chloride.
However, it is not limited to these synthesis methods.

  The polymer compound of the present invention preferably has a mass average molecular weight of 1,000 to 500,000, more preferably 2,000 to 30,000. If the mass average molecular weight is 1,000 or more, the resist material has sufficient heat resistance, and if it is 500,000 or less, the resist material has sufficient alkali solubility, and a trailing phenomenon may occur after pattern formation. Less is.

  Furthermore, in the polymer compound of the present invention, the molecular weight distribution (Mw / Mn) of the multi-component copolymer of the above formula (1) is 1.0 to 2.0, particularly 1.0 to 1.5, which is a narrow dispersion. It is preferable that With such a molecular weight distribution, there is little possibility that foreign matter will be seen on the pattern after exposure or the shape of the pattern will be deteriorated due to the low molecular weight or high molecular weight polymer. 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 polymer compound is in the above molecular weight distribution range. It is preferable.

  It is also possible to blend two or more polymers having different composition ratios, molecular weight distributions, and molecular weights.

  The polymer compound of the present invention is suitable as a base resin for a positive resist material. Such a polymer compound is used as a base resin, and an organic solvent, an acid generator, a dissolution inhibitor, a basic compound, and a surfactant. And the like are appropriately combined according to the purpose to form a positive resist material, so that the dissolution rate of the polymer compound in the developing solution is accelerated by a catalytic reaction in the exposed portion. It can be a material, resist film has high dissolution contrast and resolution, exposure margin, excellent process adaptability, good pattern shape after exposure, and better etching resistance, In particular, since acid diffusion can be suppressed, the dimensional difference in density is small, and from these facts, it is highly practical and very effective as a resist material for VLSI. Rukoto can.

  In particular, when a chemically amplified positive resist material containing an acid generator and utilizing an acid catalyzed reaction is used, the sensitivity can be increased, and various characteristics are further improved and extremely useful. .

  As described above, an organic solvent can be further added to the positive resist material of the present invention. Such an organic solvent may be any organic solvent that can dissolve the base resin, acid generator, other additives, and the like. Examples of such organic solvents include ketones such as cyclohexanone and methyl-2-n-amyl ketone, 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy- Alcohols such as 2-propanol, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, and other ethers, propylene glycol monomethyl ether acetate, propylene glycol mono Ethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, 3-ethoxy Ethyl propionate, acetate tert- butyl, tert- butyl propionate, and propylene glycol monobutyl tert- butyl ether acetate, although lactones such as γ- butyl lactone, not being limited thereto.

  These organic solvents can be used individually by 1 type or in mixture of 2 or more types. In the present invention, among these organic solvents, diethylene glycol dimethyl ether, 1-ethoxy-2-propanol, propylene glycol monomethyl ether acetate, and mixed solvents thereof, which have the highest solubility of the acid generator in the resist component, are preferably used. .

  The amount of the organic solvent used is preferably 200 to 1,000 parts, particularly 400 to 800 parts, with respect to 100 parts (parts by mass) of the base resin.

As described above, an acid generator can be further added to the positive resist material of the present invention.
As an acid generator blended in the positive resist material of the present invention,
(I) Onium salt of the following general formula (P1a-1), (P1a-2) or (P1b),
(Ii) a diazomethane derivative of the following general formula (P2):
(Iii) a glyoxime derivative of the following general formula (P3),
(Iv) a bissulfone derivative of the following general formula (P4),
(V) a sulfonic acid ester of an N-hydroxyimide compound of the following general formula (P5),
(Vi) β-ketosulfonic acid derivative,
(Vii) a disulfone derivative,
(Viii) a nitrobenzyl sulfonate derivative,
(Ix) sulfonic acid ester derivatives and the like.

Wherein R ^101a , R ^101b and R ^101c are each a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, an alkenyl group, an oxoalkyl group or an oxoalkenyl group, and an aryl having 6 to 20 carbon atoms. Group, an aralkyl group having 7 to 12 carbon atoms or an aryloxoalkyl group, part or all of hydrogen atoms of these groups may be substituted by an alkoxy group, etc. R ^101b and R ^{101c May} form a ring, and in the case of forming a ring, R ^101b and R ^101c each represent an alkylene group having 1 to 6 carbon atoms, and K ⁻ represents a non-nucleophilic counter ion.)

R ^101a , R ^101b and R ^101c may be the same as or different from each other. Specifically, as an alkyl group, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl Group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclopropylmethyl group, 4-methylcyclohexyl group, cyclohexylmethyl group, norbornyl group, adamantyl group, etc. Is mentioned. Examples of the alkenyl group include a vinyl group, an allyl group, a propenyl group, a butenyl group, a hexenyl group, and a cyclohexenyl group. Examples of the oxoalkyl group include 2-oxocyclopentyl group, 2-oxocyclohexyl group, and the like. 2-oxopropyl group, 2-cyclopentyl-2-oxoethyl group, 2-cyclohexyl-2-oxoethyl group, 2- (4 -Methylcyclohexyl) -2-oxoethyl group and the like can be mentioned. Examples of the aryl group include a phenyl group, a naphthyl group, a p-methoxyphenyl group, an m-methoxyphenyl group, an o-methoxyphenyl group, an ethoxyphenyl group, a p-tert-butoxyphenyl group, and an m-tert-butoxyphenyl group. Alkylphenyl groups such as alkoxyphenyl groups, 2-methylphenyl groups, 3-methylphenyl groups, 4-methylphenyl groups, ethylphenyl groups, 4-tert-butylphenyl groups, 4-butylphenyl groups, dimethylphenyl groups, etc. Alkyl naphthyl groups such as methyl naphthyl group and ethyl naphthyl group, alkoxy naphthyl groups such as methoxy naphthyl group and ethoxy naphthyl group, dialkyl naphthyl groups such as dimethyl naphthyl group and diethyl naphthyl group, dimethoxy naphthyl group and diethoxy naphthyl group Dialkoxynaphthyl group And the like. Examples of the aralkyl group include a benzyl group, a phenylethyl group, and a phenethyl group. As the aryloxoalkyl group, 2-aryl-2-oxoethyl group such as 2-phenyl-2-oxoethyl group, 2- (1-naphthyl) -2-oxoethyl group, 2- (2-naphthyl) -2-oxoethyl group and the like Groups and the like. K ^- a non-nucleophilic counter chloride ions as the ion, halide ions such as bromide ion, triflate, 1,1,1-trifluoroethane sulfonate, fluoroalkyl sulfonate such as nonafluorobutanesulfonate, tosylate, benzenesulfonate And aryl sulfonates such as 4-fluorobenzene sulfonate and 1,2,3,4,5-pentafluorobenzene sulfonate, and alkyl sulfonates such as mesylate and butane sulfonate.

(In the formula, R ^102a and R ^102b each represent a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms. R ¹⁰³ is a linear, branched or cyclic alkylene having 1 to 10 carbon atoms. R ^104a and R ^104b each represent a 2-oxoalkyl group having 3 to 7 carbon atoms, and K ⁻ represents a non-nucleophilic counter ion.)

Specific examples of R ^102a and R ^102b include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. , Cyclopentyl group, cyclohexyl group, cyclopropylmethyl group, 4-methylcyclohexyl group, cyclohexylmethyl group and the like. R ¹⁰³ is methylene group, ethylene group, propylene group, butylene group, pentylene group, hexylene group, heptylene group, octylene group, nonylene group, 1,4-cyclohexylene group, 1,2-cyclohexylene. Group, 1,3-cyclopentylene group, 1,4-cyclooctylene group, 1,4-cyclohexanedimethylene group and the like. ^{Examples of} R ^104a and R ^104b include a 2-oxopropyl group, a 2-oxocyclopentyl group, a 2-oxocyclohexyl group, and a 2-oxocycloheptyl group. K ^- is can be exemplified the same ones as described in the formulas (P1a-1) and (P1a-2).

(In the formula, R ¹⁰⁵ and R ¹⁰⁶ are linear, branched or cyclic alkyl groups or halogenated alkyl groups having 1 to 12 carbon atoms, aryl groups or halogenated aryl groups having 6 to 20 carbon atoms, or carbon atoms. 7 to 12 aralkyl groups are shown.)

^Examples of the alkyl group of R ¹⁰⁵ and R ¹⁰⁶ include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, amyl Group, cyclopentyl group, cyclohexyl group, cycloheptyl group, norbornyl group, adamantyl group and the like. Examples of the halogenated alkyl group include a trifluoromethyl group, a 1,1,1-trifluoroethyl group, a 1,1,1-trichloroethyl group, and a nonafluorobutyl group. As the aryl group, an alkoxyphenyl group such as a phenyl group, p-methoxyphenyl group, m-methoxyphenyl group, o-methoxyphenyl group, ethoxyphenyl group, p-tert-butoxyphenyl group, m-tert-butoxyphenyl group, Examples thereof include alkylphenyl groups such as 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, ethylphenyl group, 4-tert-butylphenyl group, 4-butylphenyl group, and dimethylphenyl group. Examples of the halogenated aryl group include a fluorophenyl group, a chlorophenyl group, and 1,2,3,4,5-pentafluorophenyl group. Examples of the aralkyl group include a benzyl group and a phenethyl group.

(Wherein R ¹⁰⁷ , R ¹⁰⁸ and R ¹⁰⁹ are each a linear, branched or cyclic alkyl group or halogenated alkyl group having 1 to 12 carbon atoms, an aryl group or halogenated aryl group having 6 to 20 carbon atoms, Or an aralkyl group having 7 to 12 carbon atoms, R ¹⁰⁸ and R ¹⁰⁹ may be bonded to each other to form a cyclic structure, and in the case of forming a cyclic structure, R ¹⁰⁸ and R ¹⁰⁹ each have 1 to 6 carbon atoms. A linear or branched alkylene group.)

Examples of the alkyl group, halogenated alkyl group, aryl group, halogenated aryl group, and aralkyl group of R ¹⁰⁷ , R ¹⁰⁸ , and R ¹⁰⁹ include the same groups as those described for R ¹⁰⁵ and R ¹⁰⁶ . ^Examples of the alkylene group for R ¹⁰⁸ and R ¹⁰⁹ include a methylene group, an ethylene group, a propylene group, a butylene group, and a hexylene group.

（式中、Ｒ^101a、Ｒ^101bは上記と同様である。）

(In the formula, R ^101a and R ^101b are the same as above.)

(In the formula, R ¹¹⁰ represents an arylene group having 6 to 10 carbon atoms, an alkylene group having 1 to 6 carbon atoms, or an alkenylene group having 2 to 6 carbon atoms, and some or all of the hydrogen atoms of these groups are further carbon atoms. It may be substituted with a linear or branched alkyl group or alkoxy group having 1 to 4 carbon atoms, a nitro group, an acetyl group, or a phenyl group, and R ¹¹¹ is a linear or branched chain having 1 to 8 carbon atoms. Or a substituted alkyl group, an alkenyl group or an alkoxyalkyl group, a phenyl group, or a naphthyl group, and part or all of the hydrogen atoms of these groups are further an alkyl group or alkoxy group having 1 to 4 carbon atoms; A phenyl group which may be substituted with an alkyl group of 4 to 4, an alkoxy group, a nitro group or an acetyl group; a heteroaromatic group having 3 to 5 carbon atoms; or a phenyl group which may be substituted with a chlorine atom or a fluorine atom.

Here, as the arylene group of R ¹¹⁰ , 1,2-phenylene group, 1,8-naphthylene group, etc., and as the alkylene group, methylene group, ethylene group, trimethylene group, tetramethylene group, phenylethylene group, norbornane Examples of the alkenylene group such as -2,3-diyl group include 1,2-vinylene group, 1-phenyl-1,2-vinylene group, 5-norbornene-2,3-diyl group and the like. The alkyl group for R ¹¹¹ is the same as R ^{101a to} R ^101c, and the alkenyl group is a vinyl group, 1-propenyl group, allyl group, 1-butenyl group, 3-butenyl group, isoprenyl group, 1- Pentenyl group, 3-pentenyl group, 4-pentenyl group, dimethylallyl group, 1-hexenyl group, 3-hexenyl group, 5-hexenyl group, 1-heptenyl group, 3-heptenyl group, 6-heptenyl group, 7-octenyl Groups such as alkoxyalkyl groups include methoxymethyl, ethoxymethyl, propoxymethyl, butoxymethyl, pentyloxymethyl, hexyloxymethyl, heptyloxymethyl, methoxyethyl, ethoxyethyl, Propoxyethyl, butoxyethyl, pentyloxyethyl, hexyloxyethyl, methoxypro Group, ethoxypropyl group, propoxypropyl group, butoxy propyl group, methoxybutyl group, ethoxybutyl group, propoxybutyl group, a methoxy pentyl group, an ethoxy pentyl group, a methoxy hexyl group, a methoxy heptyl group.

  In addition, examples of the optionally substituted alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a tert-butyl group. As the alkoxy group of ˜4, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, a tert-butoxy group and the like are an alkyl group having 1 to 4 carbon atoms, an alkoxy group, and a nitro group. As the phenyl group which may be substituted with an acetyl group, a phenyl group, a tolyl group, a p-tert-butoxyphenyl group, a p-acetylphenyl group, a p-nitrophenyl group, etc. are heterocycles having 3 to 5 carbon atoms. Examples of the aromatic group include a pyridyl group and a furyl group.

  Examples of onium salts include diphenyliodonium trifluoromethanesulfonate, trifluoromethanesulfonic acid (p-tert-butoxyphenyl) phenyliodonium, p-toluenesulfonic acid diphenyliodonium, p-toluenesulfonic acid (p-tert-butoxyphenyl) phenyl. Iodonium, triphenylsulfonium trifluoromethanesulfonate, trifluoromethanesulfonate (p-tert-butoxyphenyl) diphenylsulfonium, bis (p-tert-butoxyphenyl) phenylsulfonium trifluoromethanesulfonate, tris (p-tert) trifluoromethanesulfonate -Butoxyphenyl) sulfonium, p-toluenesulfonic acid triphenylsulfonium, p-toluenesulfonic acid p-tert-butoxyphenyl) diphenylsulfonium, bis (p-tert-butoxyphenyl) phenylsulfonium p-toluenesulfonate, tris (p-tert-butoxyphenyl) sulfonium p-toluenesulfonate, triphenyl nonafluorobutanesulfonate Sulfonium, triphenylsulfonium butanesulfonate, trimethylsulfonium trifluoromethanesulfonate, trimethylsulfonium p-toluenesulfonate, cyclohexylmethyl trifluoromethanesulfonate (2-oxocyclohexyl) sulfonium, cyclohexylmethyl p-toluenesulfonate (2-oxocyclohexyl) ) Sulfonium, dimethylphenylsulfonium trifluoromethanesulfonate, di-p-toluenesulfonic acid Tylphenylsulfonium, dicyclohexylphenylsulfonium trifluoromethanesulfonate, dicyclohexylphenylsulfonium p-toluenesulfonate, trinaphthylsulfonium trifluoromethanesulfonate, (2-norbornyl) methyl (2-oxocyclohexyl) sulfonium trifluoromethanesulfonate, ethylenebis [ And onium salts such as methyl (2-oxocyclopentyl) sulfonium trifluoromethanesulfonate] and 1,2′-naphthylcarbonylmethyltetrahydrothiophenium triflate.

  Diazomethane derivatives include bis (benzenesulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (xylenesulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (cyclopentylsulfonyl) diazomethane, bis (n-butylsulfonyl) diazomethane Bis (isobutylsulfonyl) diazomethane, bis (sec-butylsulfonyl) diazomethane, bis (n-propylsulfonyl) diazomethane, bis (isopropylsulfonyl) diazomethane, bis (tert-butylsulfonyl) diazomethane, bis (n-amylsulfonyl) diazomethane Bis (isoamylsulfonyl) diazomethane, bis (sec-amylsulfonyl) diazomethane, bis (tert-amylsulfur) Nyl) diazomethane, 1-cyclohexylsulfonyl-1- (tert-butylsulfonyl) diazomethane, 1-cyclohexylsulfonyl-1- (tert-amylsulfonyl) diazomethane, 1-tert-amylsulfonyl-1- (tert-butylsulfonyl) diazomethane And the like.

  Examples of glyoxime derivatives include bis-O- (p-toluenesulfonyl) -α-dimethylglyoxime, bis-O- (p-toluenesulfonyl) -α-diphenylglyoxime, bis-O- (p-toluenesulfonyl)- α-dicyclohexylglyoxime, bis-O- (p-toluenesulfonyl) -2,3-pentanedione glyoxime, bis-O- (p-toluenesulfonyl) -2-methyl-3,4-pentanedione glyoxime, Bis-O- (n-butanesulfonyl) -α-dimethylglyoxime, bis-O- (n-butanesulfonyl) -α-diphenylglyoxime, bis-O- (n-butanesulfonyl) -α-dicyclohexylglyoxime Bis-O- (n-butanesulfonyl) -2,3-pentanedione glyoxime, bis-O- ( -Butanesulfonyl) -2-methyl-3,4-pentanedione glyoxime, bis-O- (methanesulfonyl) -α-dimethylglyoxime, bis-O- (trifluoromethanesulfonyl) -α-dimethylglyoxime, bis -O- (1,1,1-trifluoroethanesulfonyl) -α-dimethylglyoxime, bis-O- (tert-butanesulfonyl) -α-dimethylglyoxime, bis-O- (perfluorooctanesulfonyl)- α-dimethylglyoxime, bis-O- (cyclohexanesulfonyl) -α-dimethylglyoxime, bis-O- (benzenesulfonyl) -α-dimethylglyoxime, bis-O- (p-fluorobenzenesulfonyl) -α- Dimethylglyoxime, bis-O- (p-tert-butylbenzenesulfonyl) α- dimethylglyoxime, bis -O- (xylene sulfonyl)-.alpha.-dimethylglyoxime, and bis -O- (camphorsulfonyl)-.alpha.-glyoxime derivatives such as dimethylglyoxime.

  Examples of bissulfone derivatives include bisnaphthylsulfonylmethane, bistrifluoromethylsulfonylmethane, bismethylsulfonylmethane, bisethylsulfonylmethane, bispropylsulfonylmethane, bisisopropylsulfonylmethane, bis-p-toluenesulfonylmethane, and bisbenzenesulfonylmethane. Bissulfone derivatives can be mentioned.

  Examples of β-ketosulfonic acid derivatives include β-ketosulfonic acid derivatives such as 2-cyclohexylcarbonyl-2- (p-toluenesulfonyl) propane and 2-isopropylcarbonyl-2- (p-toluenesulfonyl) propane.

  Examples of the disulfone derivative include disulfone derivatives such as diphenyl disulfone derivatives and dicyclohexyl disulfone derivatives.

  Examples of the nitrobenzyl sulfonate derivative include nitrobenzyl sulfonate derivatives such as 2,6-dinitrobenzyl p-toluenesulfonate and 2,4-dinitrobenzyl p-toluenesulfonate.

  Examples of sulfonic acid ester derivatives include 1,2,3-tris (methanesulfonyloxy) benzene, 1,2,3-tris (trifluoromethanesulfonyloxy) benzene, 1,2,3-tris (p-toluenesulfonyloxy). Mention may be made of sulfonic acid ester derivatives such as benzene.

  Further, N-hydroxysuccinimide methanesulfonic acid ester, N-hydroxysuccinimide trifluoromethanesulfonic acid ester, N-hydroxysuccinimide ethanesulfonic acid ester, N-hydroxysuccinimide 1-propanesulfonic acid ester, N-hydroxysuccinimide 2-propanesulfonic acid Ester, N-hydroxysuccinimide 1-pentanesulfonic acid ester, N-hydroxysuccinimide 1-octanesulfonic acid ester, N-hydroxysuccinimide p-toluenesulfonic acid ester, N-hydroxysuccinimide p-methoxybenzenesulfonic acid ester, N-hydroxy Succinimide 2-chloroethane sulfonate, N-hydroxysuccinimide benzene sulfonate N-hydroxysuccinimide-2,4,6-trimethylbenzenesulfonic acid ester, N-hydroxysuccinimide 1-naphthalenesulfonic acid ester, N-hydroxysuccinimide 2-naphthalenesulfonic acid ester, N-hydroxy-2-phenylsuccinimide methanesulfonic acid Ester, N-hydroxymaleimide methanesulfonate, N-hydroxymaleimide ethanesulfonate, N-hydroxy-2-phenylmaleimide methanesulfonate, N-hydroxyglutarimide methanesulfonate, N-hydroxyglutarimide benzenesulfone Acid ester, N-hydroxyphthalimidomethanesulfonic acid ester, N-hydroxyphthalimidobenzenesulfonic acid ester, N-hydroxyl Phthalimide trifluoromethanesulfonate, N-hydroxyphthalimide p-toluenesulfonate, N-hydroxynaphthalimide methanesulfonate, N-hydroxynaphthalimidebenzenesulfonate, N-hydroxy-5-norbornene-2,3- Dicarboximide methanesulfonate, N-hydroxy-5-norbornene-2,3-dicarboximide trifluoromethanesulfonate, N-hydroxy-5-norbornene-2,3-dicarboximide p-toluenesulfonate Examples thereof include sulfonic acid ester derivatives of N-hydroxyimide compounds.

In particular, triphenylsulfonium trifluoromethanesulfonate, trifluoromethanesulfonate (p-tert-butoxyphenyl) diphenylsulfonium, tris (p-tert-butoxyphenyl) sulfonium trifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate, p -Toluenesulfonic acid (p-tert-butoxyphenyl) diphenylsulfonium, p-toluenesulfonic acid tris (p-tert-butoxyphenyl) sulfonium, trifluoromethanesulfonic acid trinaphthylsulfonium, trifluoromethanesulfonic acid cyclohexylmethyl (2-oxocyclohexyl) ) Sulfonium, (2-norbornyl) methyl (2-oxocyclohexyl) sulfonyl trifluoromethanesulfonate Onium salts such as 1,2′-naphthylcarbonylmethyltetrahydrothiophenium triflate, bis (benzenesulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (n-butylsulfonyl) Diazomethane derivatives such as diazomethane, bis (isobutylsulfonyl) diazomethane, bis (sec-butylsulfonyl) diazomethane, bis (n-propylsulfonyl) diazomethane, bis (isopropylsulfonyl) diazomethane, bis (tert-butylsulfonyl) diazomethane, bis-O -Glyoxime derivatives such as-(p-toluenesulfonyl) -α-dimethylglyoxime and bis-O- (n-butanesulfonyl) -α-dimethylglyoxime, bisnaphthyl Bissulfone derivatives such as sulfonylmethane, N-hydroxysuccinimide methanesulfonate, N-hydroxysuccinimide trifluoromethanesulfonate, N-hydroxysuccinimide 1-propanesulfonate, N-hydroxysuccinimide 2-propanesulfonate, N- Hydroxysuccinimide 1-pentanesulfonic acid ester, N-hydroxysuccinimide p-toluenesulfonic acid ester, N-hydroxynaphthalimide methanesulfonic acid ester, N-hydroxynaphthalimide benzenesulfonic acid ester, etc. Derivatives are preferably used.
Furthermore, an oxime type acid generator represented by WO2004 / 074242 A2 may be added.

  In addition, the said acid generator can be used individually by 1 type or in combination of 2 or more types. Since onium salts are excellent in rectangularity improving effect and diazomethane derivatives and glyoxime derivatives are excellent in standing wave reducing effect, it is possible to finely adjust the profile by combining both.

  The addition amount of the acid generator is preferably 0.1 to 50 parts, more preferably 0.5 to 40 parts with respect to 100 parts of the base resin. If it is 0.1 part or more, the amount of acid generated during exposure is sufficient, and there is little risk of inferior sensitivity and resolving power, and if it is 50 part or less, the transmittance of the resist is lowered and there is little risk of inferior resolving power.

As described above, a dissolution inhibitor may be further added to the positive resist material of the present invention, particularly to the chemically amplified positive resist material. By blending a dissolution inhibitor, the difference in dissolution rate between the exposed area and the unexposed area can be further increased, and the resolution can be further improved.
Examples of such a dissolution inhibitor include a compound having a mass average molecular weight of 100 to 1,000, preferably 150 to 800, and having two or more phenolic hydroxyl groups in the molecule, the hydrogen atom of the phenolic hydroxyl group being acid-free. The compound substituted at a rate of 0 to 100 mol% on average as a whole by a stabilizing group or the hydrogen atom of the carboxy group of a compound having a carboxy group in the molecule as a whole at a rate of 50 to 100 mol% as a whole by an acid labile group Substituted compounds are preferred.

  The substitution rate of the hydrogen atom of the phenolic hydroxyl group by an acid labile group is on average 0 mol% or more, preferably 30 mol% or more of the entire phenolic hydroxyl group, and the upper limit is 100 mol%, more preferably 80 mol. %. The substitution rate of the hydrogen atom of the carboxy group with an acid labile group is 50 mol% or more, preferably 70 mol% or more of the entire carboxy group on average, and the upper limit is 100 mol%.

  In this case, as the compound having two or more phenolic hydroxyl groups or the compound having a carboxy group, those represented by the following formulas (D1) to (D14) are preferable.

(In the above formulae, R ²⁰¹ and R ²⁰² each represent a hydrogen atom or a linear or branched alkyl group or alkenyl group having 1 to 8 carbon atoms. R ²⁰³ represents a hydrogen atom or 1 to 8 carbon atoms. Represents a linear or branched alkyl group or alkenyl group, or — (R ²⁰⁷ ) _h COOH, wherein R ²⁰⁴ is — (CH ₂ ) _i — (i = 2 to 10), arylene having 6 to 10 carbon atoms. A group, a carbonyl group, a sulfonyl group, an oxygen atom or a sulfur atom, and R ²⁰⁵ represents an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, a carbonyl group, a sulfonyl group, an oxygen atom or a sulfur atom. R ²⁰⁶ represents a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms, an alkenyl group, or a phenyl group or naphthyl group each substituted with a hydroxyl group, and R ²⁰⁷ represents a straight chain having 1 to 10 carbon atoms. Chain or branched alkyl R ²⁰⁸ represents a hydrogen atom or a hydroxyl group, j is an integer of 0 to 5. u and h are 0 or 1. s, t, s ′, t ′, s ″, t ″ Is a number satisfying s + t = 8, s ′ + t ′ = 5, s ″ + t ″ = 4, respectively, and having at least one hydroxyl group in each phenyl skeleton. Α is a formula (D8 ), (D9) is a number that makes the molecular weight of the compound of 100 to 1,000.)

  The compounding quantity of a dissolution inhibitor is 0-50 parts with respect to 100 parts of base resins, Preferably it is 5-50 parts, More preferably, it is 10-30 parts, It can use individually or in mixture of 2 or more types. If it is 5 parts or more, sufficient resolution improvement can be obtained, and if it is 50 parts or less, the film thickness of the pattern is reduced, and there is little possibility that the resolution is lowered.

As described above, a basic compound can be further blended into the positive resist material of the present invention, particularly the chemically amplified positive resist material.
As such a basic compound, a compound capable of suppressing the diffusion rate when the acid generated from the acid generator diffuses into the resist film is suitable. By adding a basic compound, the acid diffusion rate in the resist film is suppressed and resolution is improved, sensitivity change after exposure is suppressed, and substrate and environment dependency is reduced, and exposure margin and pattern profile are reduced. Etc. can be improved.

  Examples of such basic compounds include primary, secondary, and tertiary aliphatic amines, hybrid amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having a carboxy group, and sulfonyl groups. A nitrogen-containing compound having a hydroxyl group, a nitrogen-containing compound having a hydroxyl group, a nitrogen-containing compound having a hydroxyphenyl group, an alcoholic nitrogen-containing compound, an amide derivative, an imide derivative, and the like.

  Specifically, primary aliphatic amines include ammonia, methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, tert-butylamine, pentylamine, tert- Amylamine, cyclopentylamine, hexylamine, cyclohexylamine, heptylamine, octylamine, nonylamine, decylamine, dodecylamine, cetylamine, methylenediamine, ethylenediamine, tetraethylenepentamine, etc. are exemplified as secondary aliphatic amines. Dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-butylamine, diisobutylamine, di-sec-butylamine, dipentylamine, disi Lopentylamine, dihexylamine, dicyclohexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, didodecylamine, dicetylamine, N, N-dimethylmethylenediamine, N, N-dimethylethylenediamine, N, N-dimethyltetraethylenepenta Examples of tertiary aliphatic amines include trimethylamine, triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, triisobutylamine, tri-sec-butylamine, and tripentylamine. , Tricyclopentylamine, trihexylamine, tricyclohexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, tridodecylamine, Examples include cetylamine, N, N, N ′, N′-tetramethylmethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, N′-tetramethyltetraethylenepentamine and the like. Is done.

  Examples of hybrid amines include dimethylethylamine, methylethylpropylamine, benzylamine, phenethylamine, and benzyldimethylamine.

  Specific examples of aromatic amines and heterocyclic amines include aniline derivatives (eg, aniline, N-methylaniline, N-ethylaniline, N-propylaniline, N, N-dimethylaniline, 2-methylaniline, 3- Methylaniline, 4-methylaniline, ethylaniline, propylaniline, trimethylaniline, 2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2,4-dinitroaniline, 2,6-dinitroaniline, 3,5- Dinitroaniline, N, N-dimethyltoluidine, etc.), diphenyl (p-tolyl) amine, methyldiphenylamine, triphenylamine, phenylenediamine, naphthylamine, diaminonaphthalene, pyrrole derivatives (eg pyrrole, 2H-pyrrole, 1-methylpyrrole, 2,4-dim Lupyrrole, 2,5-dimethylpyrrole, N-methylpyrrole, etc.), oxazole derivatives (eg oxazole, isoxazole etc.), thiazole derivatives (eg thiazole, isothiazole etc.), imidazole derivatives (eg imidazole, 4-methylimidazole, 4 -Methyl-2-phenylimidazole, etc.), pyrazole derivatives, furazane derivatives, pyrroline derivatives (eg pyrroline, 2-methyl-1-pyrroline etc.), pyrrolidine derivatives (eg pyrrolidine, N-methylpyrrolidine, pyrrolidinone, N-methylpyrrolidone etc.) ), Imidazoline derivatives, imidazolidine derivatives, pyridine derivatives (eg pyridine, methylpyridine, ethylpyridine, propylpyridine, butylpyridine, 4- (1-butylpentyl) pyridine, dimethyl) Lysine, trimethylpyridine, triethylpyridine, phenylpyridine, 3-methyl-2-phenylpyridine, 4-tert-butylpyridine, diphenylpyridine, benzylpyridine, methoxypyridine, butoxypyridine, dimethoxypyridine, 1-methyl-2-pyridine, 4-pyrrolidinopyridine, 1-methyl-4-phenylpyridine, 2- (1-ethylpropyl) pyridine, aminopyridine, dimethylaminopyridine, etc.), pyridazine derivatives, pyrimidine derivatives, pyrazine derivatives, pyrazoline derivatives, pyrazolidine derivatives, piperidine Derivatives, piperazine derivatives, morpholine derivatives, indole derivatives, isoindole derivatives, 1H-indazole derivatives, indoline derivatives, quinoline derivatives (eg quinoline, 3-quinoline carbo Nitriles), isoquinoline derivatives, cinnoline derivatives, quinazoline derivatives, quinoxaline derivatives, phthalazine derivatives, purine derivatives, pteridine derivatives, carbazole derivatives, phenanthridine derivatives, acridine derivatives, phenazine derivatives, 1,10-phenanthroline derivatives, adenine derivatives, adenosine Examples include derivatives, guanine derivatives, guanosine derivatives, uracil derivatives, uridine derivatives and the like.

  Furthermore, examples of the nitrogen-containing compound having a carboxy group include aminobenzoic acid, indolecarboxylic acid, amino acid derivatives (for example, nicotinic acid, alanine, arginine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, glycylleucine, leucine, methionine. , Phenylalanine, threonine, lysine, 3-aminopyrazine-2-carboxylic acid, methoxyalanine) and the like, and examples of the nitrogen-containing compound having a sulfonyl group include 3-pyridinesulfonic acid, pyridinium p-toluenesulfonate, and the like. Nitrogen-containing compounds having a hydroxyl group, nitrogen-containing compounds having a hydroxyphenyl group, and alcoholic nitrogen-containing compounds include 2-hydroxypyridine, aminocresol, 2,4-quinolinediol, and 3-indolemethanol. Drate, monoethanolamine, diethanolamine, triethanolamine, N-ethyldiethanolamine, N, N-diethylethanolamine, triisopropanolamine, 2,2'-iminodiethanol, 2-aminoethanol, 3-amino-1-propanol 4-amino-1-butanol, 4- (2-hydroxyethyl) morpholine, 2- (2-hydroxyethyl) pyridine, 1- (2-hydroxyethyl) piperazine, 1- [2- (2-hydroxyethoxy) Ethyl] piperazine, piperidineethanol, 1- (2-hydroxyethyl) pyrrolidine, 1- (2-hydroxyethyl) -2-pyrrolidinone, 3-piperidino-1,2-propanediol, 3-pyrrolidino-1,2-propane Diol, 8-hydroxyuroli , 3-cuincridinol, 3-tropanol, 1-methyl-2-pyrrolidineethanol, 1-aziridineethanol, N- (2-hydroxyethyl) phthalimide, N- (2-hydroxyethyl) isonicotinamide, etc. Illustrated. Examples of amide derivatives include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide and the like. Examples of imide derivatives include phthalimide, succinimide, maleimide and the like.

Furthermore, 1 type, or 2 or more types chosen from the basic compound shown by the following general formula (B) -1 can also be mix | blended.
N (X) _n (Y) _3-n (B) -1
(In the formula, n is 1, 2 or 3. The side chain X may be the same or different and can be represented by the following general formulas (X) -1 to (X) -3. The side chain Y is It represents the same or different hydrogen atom or linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, and may contain an ether group or a hydroxyl group, and Xs may combine to form a ring. May be.)

Here, R ³⁰⁰ , R ³⁰² and R ³⁰⁵ are linear or branched alkylene groups having 1 to 4 carbon atoms, and R ³⁰¹ and R ³⁰⁴ are hydrogen atoms, linear and branched chains having 1 to 20 carbon atoms. Or a cyclic alkyl group, which may contain one or a plurality of hydroxy groups, ether groups, ester groups and lactone rings. R ³⁰³ is a single bond, a linear or branched alkylene group having 1 to 4 carbon atoms, R ³⁰⁶ is a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a hydroxy group, One or a plurality of ether groups, ester groups and lactone rings may be contained.

Specific examples of the compound represented by the general formula (B) -1 are given below.
Tris (2-methoxymethoxyethyl) amine, tris {2- (2-methoxyethoxy) ethyl} amine, tris {2- (2-methoxyethoxymethoxy) ethyl} amine, tris {2- (1-methoxyethoxy) ethyl } Amine, Tris {2- (1-ethoxyethoxy) ethyl} amine, Tris {2- (1-ethoxypropoxy) ethyl} amine, Tris [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] amine, 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo [8.8.8] hexacosane, 4,7,13,18-tetraoxa-1,10-diazabicyclo [8.5.5] Eicosane, 1,4,10,13-tetraoxa-7,16-diazabicyclooctadecane, 1-aza-12-crown-4 1-aza-15-crown-5, 1-aza-18-crown-6, tris (2-formyloxyethyl) amine, tris (2-acetoxyethyl) amine, tris (2-propionyloxyethyl) amine, tris (2-butyryloxyethyl) amine, tris (2-isobutyryloxyethyl) amine, tris (2-valeryloxyethyl) amine, tris (2-pivaloyloxyethyl) amine, N, N-bis (2-acetoxyethyl) 2- (acetoxyacetoxy) ethylamine, tris (2-methoxycarbonyloxyethyl) amine, tris (2-tert-butoxycarbonyloxyethyl) amine, tris [2- (2-oxopropoxy) ethyl] Amine, tris [2- (methoxycarbonylmethyl) oxyethyl] amine Tris [2- (tert-butoxycarbonylmethyloxy) ethyl] amine, tris [2- (cyclohexyloxycarbonylmethyloxy) ethyl] amine, tris (2-methoxycarbonylethyl) amine, tris (2-ethoxycarbonylethyl) amine N, N-bis (2-hydroxyethyl) 2- (methoxycarbonyl) ethylamine, N, N-bis (2-acetoxyethyl) 2- (methoxycarbonyl) ethylamine, N, N-bis (2-hydroxyethyl) 2- (ethoxycarbonyl) ethylamine, N, N-bis (2-acetoxyethyl) 2- (ethoxycarbonyl) ethylamine, N, N-bis (2-hydroxyethyl) 2- (2-methoxyethoxycarbonyl) ethylamine, N , N-bis (2-acetoxyethyl) 2- (2-methoxyethoxycarbonyl) ethylamine, N, N-bis (2-hydroxyethyl) 2- (2-hydroxyethoxycarbonyl) ethylamine, N, N-bis (2-acetoxyethyl) 2- (2-acetoxy) Ethoxycarbonyl) ethylamine, N, N-bis (2-hydroxyethyl) 2-[(methoxycarbonyl) methoxycarbonyl] ethylamine, N, N-bis (2-acetoxyethyl) 2-[(methoxycarbonyl) methoxycarbonyl] ethylamine N, N-bis (2-hydroxyethyl) 2- (2-oxopropoxycarbonyl) ethylamine, N, N-bis (2-acetoxyethyl) 2- (2-oxopropoxycarbonyl) ethylamine, N, N-bis (2-hydroxyethyl) 2- (tetrahydrofurfuryl Oxycarbonyl) ethylamine, N, N-bis (2-acetoxyethyl) 2- (tetrahydrofurfuryloxycarbonyl) ethylamine, N, N-bis (2-hydroxyethyl) 2-[(2-oxotetrahydrofuran-3-yl ) Oxycarbonyl] ethylamine, N, N-bis (2-acetoxyethyl) 2-[(2-oxotetrahydrofuran-3-yl) oxycarbonyl] ethylamine, N, N-bis (2-hydroxyethyl) 2- (4 -Hydroxybutoxycarbonyl) ethylamine, N, N-bis (2-formyloxyethyl) 2- (4-formyloxybutoxycarbonyl) ethylamine, N, N-bis (2-formyloxyethyl) 2- (2-formyloxy) Ethoxycarbonyl) ethylamine, N, N-bis (2- Toxiethyl) 2- (methoxycarbonyl) ethylamine, N- (2-hydroxyethyl) bis [2- (methoxycarbonyl) ethyl] amine, N- (2-acetoxyethyl) bis [2- (methoxycarbonyl) ethyl] amine, N- (2-hydroxyethyl) bis [2- (ethoxycarbonyl) ethyl] amine, N- (2-acetoxyethyl) bis [2- (ethoxycarbonyl) ethyl] amine, N- (3-hydroxy-1-propyl) ) Bis [2- (methoxycarbonyl) ethyl] amine, N- (3-acetoxy-1-propyl) bis [2- (methoxycarbonyl) ethyl] amine, N- (2-methoxyethyl) bis [2- (methoxy Carbonyl) ethyl] amine, N-butylbis [2- (methoxycarbonyl) ethyl] amine, N-butyl Rubis [2- (2-methoxyethoxycarbonyl) ethyl] amine, N-methylbis (2-acetoxyethyl) amine, N-ethylbis (2-acetoxyethyl) amine, N-methylbis (2-pivaloyloxyethyl) amine N-ethylbis [2- (methoxycarbonyloxy) ethyl] amine, N-ethylbis [2- (tert-butoxycarbonyloxy) ethyl] amine, tris (methoxycarbonylmethyl) amine, tris (ethoxycarbonylmethyl) amine, N -Butylbis (methoxycarbonylmethyl) amine, N-hexylbis (methoxycarbonylmethyl) amine, and β- (diethylamino) -δ-valerolactone can be exemplified, but are not limited thereto.

  Furthermore, 1 type, or 2 or more types of the basic compound which has a cyclic structure shown by the following general formula (B) -2 can also be added.

（式中、Ｘは前述の通り、Ｒ³⁰⁷は炭素数２〜２０の直鎖状又は分岐状のアルキレン基であり、カルボニル基、エーテル基、エステル基又はスルフィドを１個あるいは複数個含んでいてもよい。）

(In the formula, as described above, R ³⁰⁷ is a linear or branched alkylene group having 2 to 20 carbon atoms, and includes one or more carbonyl groups, ether groups, ester groups or sulfides. May be.)

  Specific examples of the formula (B) -2 include 1- [2- (methoxymethoxy) ethyl] pyrrolidine, 1- [2- (methoxymethoxy) ethyl] piperidine, 4- [2- (methoxymethoxy) ethyl. ] Morpholine, 1- [2-[(2-methoxyethoxy) methoxy] ethyl] pyrrolidine, 1- [2-[(2-methoxyethoxy) methoxy] ethyl] piperidine, 4- [2-[(2-methoxyethoxy) ) Methoxy] ethyl] morpholine, 2- (1-pyrrolidinyl) ethyl acetate, 2-piperidinoethyl acetate, 2-morpholinoethyl acetate, 2- (1-pyrrolidinyl) ethyl formate, 2-piperidinoethyl propionate, 2-morpholinoethyl acetoxyacetate , 2- (1-pyrrolidinyl) ethyl methoxyacetate, 4- [2- (methoxycarbonyloxy) ethyl Morpholine, 1- [2- (t-butoxycarbonyloxy) ethyl] piperidine, 4- [2- (2-methoxyethoxycarbonyloxy) ethyl] morpholine, methyl 3- (1-pyrrolidinyl) propionate, 3-piperidi Methyl nopropionate, methyl 3-morpholinopropionate, methyl 3- (thiomorpholino) propionate, methyl 2-methyl-3- (1-pyrrolidinyl) propionate, ethyl 3-morpholinopropionate, 3-piperidinopropion Methoxycarbonylmethyl acid, 2-hydroxyethyl 3- (1-pyrrolidinyl) propionate, 2-acetoxyethyl 3-morpholinopropionate, 2-oxotetrahydrofuran-3-yl 3- (1-pyrrolidinyl) propionate, 3-morpholino Propionic acid tetrahydrofur Ryl, glycidyl 3-piperidinopropionate, 2-methoxyethyl 3-morpholinopropionate, 2- (2-methoxyethoxy) ethyl 3- (1-pyrrolidinyl) propionate, butyl 3-morpholinopropionate, 3-pi Cyclohexyl peridinopropionate, α- (1-pyrrolidinyl) methyl-γ-butyrolactone, β-piperidino-γ-butyrolactone, β-morpholino-δ-valerolactone, methyl 1-pyrrolidinyl acetate, methyl piperidinoacetate, methyl morpholinoacetate, Mention may be made of methyl thiomorpholinoacetate, ethyl 1-pyrrolidinyl acetate, 2-methoxyethyl morpholinoacetate.

  Furthermore, a basic compound containing a cyano group represented by the following general formulas (B) -3 to (B) -6 can be added.

（式中、Ｘ、Ｒ³⁰⁷、ｎは前述の通り、Ｒ³⁰⁸、Ｒ³⁰⁹は同一又は異種の炭素数１〜４の直鎖状又は分岐状のアルキレン基である。）

(In the formula, X, R ³⁰⁷ and n are as described above, and R ³⁰⁸ and R ³⁰⁹ are the same or different linear or branched alkylene groups having 1 to 4 carbon atoms.)

  Specific examples of the base containing a cyano group include 3- (diethylamino) propiononitrile, N, N-bis (2-hydroxyethyl) -3-aminopropiononitrile, and N, N-bis (2-acetoxyethyl). -3-aminopropiononitrile, N, N-bis (2-formyloxyethyl) -3-aminopropiononitrile, N, N-bis (2-methoxyethyl) -3-aminopropiononitrile, N, N -Bis [2- (methoxymethoxy) ethyl] -3-aminopropiononitrile, methyl N- (2-cyanoethyl) -N- (2-methoxyethyl) -3-aminopropionate, N- (2-cyanoethyl) -N- (2-hydroxyethyl) -3-aminopropionic acid methyl, N- (2-acetoxyethyl) -N- (2-cyanoethyl) -3-aminopro Methyl onate, N- (2-cyanoethyl) -N-ethyl-3-aminopropiononitrile, N- (2-cyanoethyl) -N- (2-hydroxyethyl) -3-aminopropiononitrile, N- ( 2-acetoxyethyl) -N- (2-cyanoethyl) -3-aminopropiononitrile, N- (2-cyanoethyl) -N- (2-formyloxyethyl) -3-aminopropiononitrile, N- (2 -Cyanoethyl) -N- (2-methoxyethyl) -3-aminopropiononitrile, N- (2-cyanoethyl) -N- [2- (methoxymethoxy) ethyl] -3-aminopropiononitrile, N- ( 2-cyanoethyl) -N- (3-hydroxy-1-propyl) -3-aminopropiononitrile, N- (3-acetoxy-1-propyl) -N- (2 Cyanoethyl) -3-aminopropiononitrile, N- (2-cyanoethyl) -N- (3-formyloxy-1-propyl) -3-aminopropiononitrile, N- (2-cyanoethyl) -N-tetrahydrofur Furyl-3-aminopropiononitrile, N, N-bis (2-cyanoethyl) -3-aminopropiononitrile, diethylaminoacetonitrile, N, N-bis (2-hydroxyethyl) aminoacetonitrile, N, N-bis ( 2-acetoxyethyl) aminoacetonitrile, N, N-bis (2-formyloxyethyl) aminoacetonitrile, N, N-bis (2-methoxyethyl) aminoacetonitrile, N, N-bis [2- (methoxymethoxy) ethyl Aminoacetonitrile, N-cyanomethyl-N- (2-methoxyethyl) ) Methyl 3-aminopropionate, methyl N-cyanomethyl-N- (2-hydroxyethyl) -3-aminopropionate, methyl N- (2-acetoxyethyl) -N-cyanomethyl-3-aminopropionate, N -Cyanomethyl-N- (2-hydroxyethyl) aminoacetonitrile, N- (2-acetoxyethyl) -N- (cyanomethyl) aminoacetonitrile, N-cyanomethyl-N- (2-formyloxyethyl) aminoacetonitrile, N-cyanomethyl -N- (2-methoxyethyl) aminoacetonitrile, N-cyanomethyl-N- [2- (methoxymethoxy) ethyl] aminoacetonitrile, N- (cyanomethyl) -N- (3-hydroxy-1-propyl) aminoacetonitrile, N- (3-acetoxy-1-propyl) -N (Cyanomethyl) aminoacetonitrile, N-cyanomethyl-N- (3-formyloxy-1-propyl) aminoacetonitrile, N, N-bis (cyanomethyl) aminoacetonitrile, 1-pyrrolidinepropiononitrile, 1-piperidinepropiononitrile, 4-morpholinepropiononitrile, 1-pyrrolidineacetonitrile, 1-piperidineacetonitrile, 4-morpholineacetonitrile, cyanomethyl 3-diethylaminopropionate, cyanomethyl N, N-bis (2-hydroxyethyl) -3-aminopropionate, N, Cyanomethyl N-bis (2-acetoxyethyl) -3-aminopropionate, cyanomethyl N, N-bis (2-formyloxyethyl) -3-aminopropionate, N, N-bis (2-methoxyethyl) Cyanomethyl 3-aminopropionate, N, N-bis [2- (methoxymethoxy) ethyl] -3-aminopropionate cyanomethyl, 3-diethylaminopropionic acid (2-cyanoethyl), N, N-bis (2-hydroxyethyl) ) -3-Aminopropionic acid (2-cyanoethyl), N, N-bis (2-acetoxyethyl) -3-aminopropionic acid (2-cyanoethyl), N, N-bis (2-formyloxyethyl) -3 Aminopropionic acid (2-cyanoethyl), N, N-bis (2-methoxyethyl) -3-aminopropionic acid (2-cyanoethyl), N, N-bis [2- (methoxymethoxy) ethyl] -3- Aminopropionic acid (2-cyanoethyl), 1-pyrrolidinepropionate cyanomethyl, 1-piperidinepropionate cyano Examples include methyl, cyanomethyl 4-morpholine propionate, 1-pyrrolidinepropionic acid (2-cyanoethyl), 1-piperidinepropionic acid (2-cyanoethyl), 4-morpholine propionic acid (2-cyanoethyl).

  In addition, the compounding quantity of the base compound of this invention is 0.001-2 parts with respect to 100 parts of base resins, Especially 0.01-1 part is suitable. If the blending amount is 0.001 part or more, a sufficient blending effect is obtained, and if it is 2 parts or less, there is little fear of lowering the sensitivity.

  Furthermore, a compound having a group represented by ≡C—COOH in the molecule can be blended in the positive resist material of the present invention. As such a compound, for example, one or more compounds selected from the following group I and group II can be used, but are not limited thereto. By blending this component, the PED (post exposure delay) stability of the resist is improved, and the edge roughness on the nitride film substrate is improved.

[Group I]
A part or all of the hydrogen atoms of the phenolic hydroxyl groups of the compounds represented by the following general formulas (A1) to (A10) are converted to —R ⁴⁰¹ —COOH (where R ⁴⁰¹ is a linear or branched alkylene having 1 to 10 carbon atoms). The molar ratio of the phenolic hydroxyl group (C) in the molecule to the group (D) represented by ≡C—COOH is C / (C + D) = 0.1 to 1.0. Compound.

(In the formula, R ⁴⁰⁸ represents a hydrogen atom or a methyl group. R ⁴⁰² and R ⁴⁰³ each represents a hydrogen atom or a linear or branched alkyl group or alkenyl group having 1 to 8 carbon atoms. R ⁴⁰⁴ represents It represents a hydrogen atom, a linear or branched alkyl group or alkenyl group having 1 to 8 carbon atoms, or a — (R ⁴⁰⁹ ) _h —COOR ′ group (R ′ represents a hydrogen atom or —R ⁴⁰⁹ —COOH). ⁴⁰⁵ represents — (CH ₂ ) _i — (i = 2 to 10), an arylene group having 6 to 10 carbon atoms, a carbonyl group, a sulfonyl group, an oxygen atom or a sulfur atom, and R ⁴⁰⁶ represents an alkylene having 1 to 10 carbon atoms. Group, an arylene group having 6 to 10 carbon atoms, a carbonyl group, a sulfonyl group, an oxygen atom or a sulfur atom, R ⁴⁰⁷ is a hydrogen atom or a linear or branched alkyl group having 1 to 8 carbon atoms, an alkenyl group, Phenyls each substituted with a hydroxyl group Or .R ⁴⁰⁹ showing a naphthyl group is a straight or branched alkyl or alkenyl group or -R showing a ⁴¹¹ -COOH groups .R ⁴¹⁰ is hydrogen atom or a straight-1 to 8 carbon atoms A chain or branched alkyl group, an alkenyl group, or —R ⁴¹¹ —COOH group, R ⁴¹¹ represents a linear or branched alkylene group having 1 to 10 carbon atoms, j is 0 to 3, s1 s4 and t1 to t4 satisfy s1 + t1 = 8, s2 + t2 = 5, s3 + t3 = 4, and s4 + t4 = 6, respectively, and each phenyl skeleton has at least one hydroxyl group, and κ is a formula (A6). Is a number having a mass average molecular weight of 1,000 to 5,000, λ is a number having a compound of formula (A7) having a mass average molecular weight of 1,000 to 10,000, and u and h are 0 or 1)

[Group II]
Compounds represented by the following general formulas (A11) to (A15).

（Ｒ⁴⁰²、Ｒ⁴⁰³、Ｒ⁴¹¹は上記と同様の意味を示す。Ｒ⁴¹²は水素原子又は水酸基を示す。ｓ５、ｔ５は、ｓ５≧０、ｔ５≧０で、ｓ５＋ｔ５＝５を満足する数である。ｈ’は０又は１である。）

(R ⁴⁰² , R ⁴⁰³ , and R ⁴¹¹ have the same meanings as above. R ⁴¹² represents a hydrogen atom or a hydroxyl group. S5 and t5 are numbers satisfying s5 + t5 = 5 when s5 ≧ 0 and t5 ≧ 0. H 'is 0 or 1.)

  Specific examples of this component include, but are not limited to, compounds represented by the following general formulas (AI-1) to (AI-14) and (AII-1) to (AII-10). It is not a thing.

（式中、Ｒ’’は水素原子又はＣＨ₂ＣＯＯＨ基を示し、各化合物においてＲ’’の１０〜１００モル％はＣＨ₂ＣＯＯＨ基である。α、κは上記と同様の意味を示す。）

(In the formula, R ″ represents a hydrogen atom or a CH ₂ COOH group, and in each compound, 10 to 100 mol% of R ″ is a CH ₂ COOH group. Α and κ have the same meanings as described above. )

  In addition, the compound which has group shown by (≡C-COOH) in the said molecule | numerator can be used individually by 1 type or in combination of 2 or more types.

  The amount of the compound having a group represented by ≡C—COOH in the molecule is 0 to 5 parts, preferably 0.1 to 5 parts, more preferably 0.1 to 3 parts, relative to 100 parts of the base resin. More preferably, it is 0.1 to 2 parts. If it is 5 parts or less, there is little possibility that the resolution of the resist material is lowered.

  Furthermore, a dissolution control agent comprising a compound having a plurality of bisphenol groups substituted with an acid labile group represented by the following general formula BP- (1) can be added to the positive resist material of the present invention.

(Wherein R ⁵⁰¹ is the same or different hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or A halogen atom, R ⁵⁰² is the same or different independently a hydrogen atom or an acid labile group, n is an integer of 2 to 4. Z is a carbon number of 5 to 40 including the carbon atoms in the formula. An alkyl group having a cyclic structure, a bridged cyclic hydrocarbon group, or a condensed polycyclic hydrocarbon group, which may have a heteroatom such as sulfur.)

As the acid labile group in the general formula BP- (1), those selected from those described above can be used. Specific examples of the compound represented by the general formula BP- (1) are shown below. In the following formulae, R ⁵⁰¹ and R ⁵⁰² are the same as described above.

  In addition, a dissolution control agent composed of calixarenes substituted with an acid labile group described in JP-A No. 11-322656 can be added to the positive resist material of the present invention.

As described above, a surfactant can be further added to the positive resist material of the present invention. By adding a surfactant, the coating property of the resist material can be further improved or controlled.
Examples of such surfactants include, but are not limited to, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene olein ether, Polyoxyethylene alkyl allyl ethers such as polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol, polyoxyethylene polyoxypropylene block copolymers, sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate and sorbitan monostearate , Polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monos Nonionic surfactants of polyoxyethylene sorbitan fatty acid esters such as allate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate, F-top EF301, EF303, EF352 (Tochem Products), MegaFuck F171, F172, F173 (Dainippon Ink Chemical Co., Ltd.), Florard FC430, FC431, FC-4430 (Sumitomo 3M), Asahi Guard AG710, Surflon S-381, S-382, SC101, SC102, SC103, SC104, SC105, SC106, Surfinol E1004 , Fluorosurfactants such as KH-10, KH-20, KH-30, KH-40 (Asahi Glass), organosiloxane polymers KP-341, X-70-092, -70-093 (Shin-Etsu Chemical), acrylic acid or methacrylic acid Polyflow No. 75, no. 95 (Kyoeisha Yushi Chemical Industry Co., Ltd.), among which FC430, FC-4430, Surflon S-381, Surfynol E1004, KH-20, KH-30 are preferred. These can be used alone or in combination of two or more.

  The addition amount of the surfactant in the positive resist material of the present invention, particularly the chemically amplified positive resist material, is 2 parts or less, preferably 1 part or less with respect to 100 parts of the base resin in the resist material.

  The positive resist material of the present invention, for example, a chemically amplified positive resist material containing an organic solvent, a polymer compound represented by the general formula (1), an acid generator, and a basic compound is used for manufacturing various integrated circuits. In the case, a known lithography technique can be applied although it is not particularly limited.

  That is, it is possible to form a pattern by performing at least a step of applying the positive resist material onto the substrate, a step of exposing to high energy rays after the heat treatment, and a step of developing using a developer.

For example, the positive resist material of the present invention is applied to an integrated circuit manufacturing substrate (Si, SiO ₂ , SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflection film, etc.) or a mask circuit manufacturing substrate (Cr , CrO, CrON, MoSi, etc.) by a suitable coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, etc., so that the coating film thickness is 0.1 to 2.0 μm. To do. 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, the target pattern is exposed through a predetermined mask or directly with a light source selected from high energy rays such as ultraviolet rays, far ultraviolet rays, electron beams, X-rays, excimer lasers, γ rays, and synchrotron radiation. It is preferable to expose so that the exposure amount is about 1 to 200 mJ / cm ² , preferably 10 to 100 mJ / cm ² , or 0.1 to 100 μC, and preferably about 0.5 to 50 μC. 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.

Further, 0.1 to 5% by mass, preferably 2 to 3% by mass of a developer of an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH) is used for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes. Development is performed by a conventional method such as a dip method, a paddle method, or a spray method. As a result, the irradiated portion is dissolved in the developer, and the unexposed portion 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 by electron beam, soft X-ray, X-ray, γ-ray and synchrotron radiation among high energy rays.

  EXAMPLES Hereinafter, although a synthesis example, a comparative synthesis example, an Example, and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example etc. In the following, GPC refers to gel permeation chromatography.

[Synthesis Example 1]
To a 2 L flask, 35.2 g of 4-t-butoxystyrene, 63.6 g of 6-acetoxy-2-vinylnaphthalene, 81 g of 4-acetoxystyrene, and 250 g of toluene as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 8.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C., followed by reaction for 15 hours. This reaction solution is precipitated in 5 L of isopropyl alcohol, and the resulting white solid is dissolved again in 500 mL of methanol and 800 mL of tetrahydrofuran. 50 g of triethylamine and 50 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated, dissolved in 500 mL of acetone, precipitated, filtered and dried at 60 ° C. as described above to obtain a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
4-t-butoxystyrene: 6-hydroxy-2-vinylnaphthalene: 4-hydroxystyrene = 0.2: 0.3: 0.5
Mass average molecular weight (Mw) = 8,900
Molecular weight distribution (Mw / Mn) = 1.84
This polymer compound is referred to as polymer 1 (polymer1).

[Synthesis Example 2]
To a 2 L flask, 38.0 g of 4-t-amyloxystyrene, 63.6 g of 6-acetoxy-2-vinylnaphthalene, 81 g of 4-acetoxystyrene, and 250 g of toluene as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 8.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C., followed by reaction for 15 hours. This reaction solution is precipitated in 5 L of isopropyl alcohol, and the resulting white solid is dissolved again in 500 mL of methanol and 800 mL of tetrahydrofuran. 50 g of triethylamine and 50 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated, dissolved in 500 mL of acetone, precipitated, filtered and dried at 60 ° C. as described above to obtain a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
4-t-amyloxystyrene: 6-hydroxy-2-vinylnaphthalene: 4-hydroxystyrene = 0.2: 0.3: 0.5
Mass average molecular weight (Mw) = 8,300
Molecular weight distribution (Mw / Mn) = 1.80
This high molecular compound is referred to as polymer 2 (polymer2).

[Synthesis Example 3]
To a 2 L flask were added 24.8 g of 2-ethyl-2-adamantane methacrylate, 17.6 g of 4-t-butoxystyrene, 169.6 g of 6-acetoxy-2-vinylnaphthalene, and 250 g of toluene as a solvent. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 8.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C., followed by reaction for 15 hours. This reaction solution is precipitated in 5 L of isopropyl alcohol, and the resulting white solid is dissolved again in 500 mL of methanol and 800 mL of tetrahydrofuran. 50 g of triethylamine and 50 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated, dissolved in 500 mL of acetone, precipitated, filtered and dried at 60 ° C. as described above to obtain a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Methacrylic acid-2-ethyl-2-adamantane: 4-t-butoxystyrene: 6-hydroxy-2-vinylnaphthalene = 0.1: 0.1: 0.8
Mass average molecular weight (Mw) = 7,800
Molecular weight distribution (Mw / Mn) = 1.84
This high molecular compound is referred to as polymer 3 (polymer3).

[Synthesis Example 4]
In a 2 L flask, methacrylic acid-3-ethyl-3-exotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodecanyl 27.4 g, 4-t-butoxystyrene 17.6 g, 6-acetoxy-2-vinylnaphthalene 169.6 g, and toluene 250 g as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 8.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C., followed by reaction for 15 hours. This reaction solution is precipitated in 5 L of isopropyl alcohol, and the resulting white solid is dissolved again in 500 mL of methanol and 800 mL of tetrahydrofuran. 50 g of triethylamine and 50 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated, dissolved in 500 mL of acetone, precipitated, filtered and dried at 60 ° C. as described above to obtain a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Methacrylic acid-3-ethyl-3-exotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodecanyl: 4-t-butoxystyrene: 6-hydroxy-2-vinylnaphthalene = 0.1: 0.1: 0.8
Mass average molecular weight (Mw) = 7,300
Molecular weight distribution (Mw / Mn) = 1.72
This polymer compound is referred to as polymer 4 (polymer4).

[Synthesis Example 5]
To a 2 L flask, 51.2 g of 6-methoxyisobutyloxy-2-vinylnaphthalene, 63.6 g of 6-acetoxy-2-vinylnaphthalene, 81 g of 4-acetoxystyrene, and 250 g of toluene as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 8.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C., followed by reaction for 15 hours. This reaction solution is precipitated in 5 L of isopropyl alcohol, and the resulting white solid is dissolved again in 500 mL of methanol and 800 mL of tetrahydrofuran. 50 g of triethylamine and 50 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated, dissolved in 500 mL of acetone, precipitated, filtered and dried at 60 ° C. as described above to obtain a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
6-methoxyisobutyloxy-2-vinylnaphthalene: 6-hydroxy-2-vinylnaphthalene: 4-hydroxystyrene = 0.2: 0.3: 0.5
Mass average molecular weight (Mw) = 10,900
Molecular weight distribution (Mw / Mn) = 1.75
This polymer is designated as polymer 5 (polymer5).

[Synthesis Example 6]
To a 2 L flask was added 49.4 g of 4-methoxyisobutyloxystyrene, 161.1 g of 6-acetoxy-2-vinylnaphthalene, and 250 g of toluene as a solvent. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 8.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C., followed by reaction for 15 hours. This reaction solution is precipitated in 5 L of isopropyl alcohol, and the resulting white solid is dissolved again in 500 mL of methanol and 800 mL of tetrahydrofuran. 50 g of triethylamine and 50 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated, dissolved in 500 mL of acetone, precipitated, filtered and dried at 60 ° C. as described above to obtain a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
4-methoxyisobutyloxystyrene: 6-hydroxy-2-vinylnaphthalene = 0.24: 0.76
Mass average molecular weight (Mw) = 11,300
Molecular weight distribution (Mw / Mn) = 1.62
This polymer is designated as polymer 6 (polymer 6).

[Synthesis Example 7]
In a 2 L flask, 4-methoxyisobutyloxystyrene 41.2 g, 6-acetoxy-2-vinylnaphthalene 159.0 g, 4-acrylic acid oxyphenyldiphenylsulfonium bis (perfluorobutylsulfonyl) imide 24.2 g, and toluene as a solvent 250 g was added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 8.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C., followed by reaction for 15 hours. This reaction solution is precipitated in 5 L of isopropyl alcohol, and the resulting white solid is dissolved again in 500 mL of methanol and 800 mL of tetrahydrofuran. 50 g of triethylamine and 50 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated, dissolved in 500 mL of acetone, precipitated, filtered and dried at 60 ° C. as described above to obtain a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
4-methoxyisobutyloxystyrene: 6-hydroxy-2-vinylnaphthalene: 4-acrylic acid oxyphenyldiphenylsulfonium bis (perfluorobutylsulfonyl) imide = 0.20: 0.75: 0.05
Mass average molecular weight (Mw) = 10,100
Molecular weight distribution (Mw / Mn) = 1.68
This high molecular compound is referred to as polymer 7 (polymer7).

[Synthesis Example 8]
To a 2 L flask, 74.5 g of the following monomer 1 (Monomer1), 82.2 g of 6-acetoxy-2-vinylnaphthalene, 64.8 g of acetoxystyrene, and 250 g of toluene as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 8.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C., followed by reaction for 15 hours. This reaction solution is precipitated in 5 L of isopropyl alcohol, and the resulting white solid is dissolved again in 500 mL of methanol and 800 mL of tetrahydrofuran. 50 g of triethylamine and 50 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated, dissolved in 500 mL of acetone, precipitated, filtered and dried at 60 ° C. as described above to obtain a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 1: 6-hydroxy-2-vinylnaphthalene: 4-hydroxystyrene = 0.25: 0.35: 0.40
Mass average molecular weight (Mw) = 9,300
Molecular weight distribution (Mw / Mn) = 1.58
This polymer compound is designated as polymer 8 (polymer8).

[Synthesis Example 9]
To a 2 L flask, 87.5 g of the following monomer 2 (Monomer2), 121.5 g of 4-acetoxystyrene, and 250 g of toluene as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 8.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C., followed by reaction for 15 hours. This reaction solution is precipitated in 5 L of isopropyl alcohol, and the resulting white solid is dissolved again in 500 mL of methanol and 800 mL of tetrahydrofuran. 50 g of triethylamine and 50 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated, dissolved in 500 mL of acetone, precipitated, filtered and dried at 60 ° C. as described above to obtain a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 4-hydroxystyrene = 0.25: 0.75
Mass average molecular weight (Mw) = 7,600
Molecular weight distribution (Mw / Mn) = 1.67
This polymer compound is designated as polymer 9 (polymer9).

[Comparative Synthesis Example 1]
The following two-component polymers were synthesized by the same method as in the above synthesis example.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Hydroxystyrene: Methacrylic acid 1-ethylcyclopentyl ester = 0.71: 0.29
Mass average molecular weight (Mw) = 16,100
Molecular weight distribution (Mw / Mn) = 1.70
This high molecular compound is referred to as comparative polymer 1 (comparative polymer 1).

[Comparative Synthesis Example 2]
Using a 2 L flask, 40 g of polyhydroxystyrene (Mw = 11,000, Mw / Mn = 1.08) was dissolved in 400 mL of tetrahydrofuran, and 1.4 g of methanesulfonic acid and 12.3 g of ethyl vinyl ether were added. The mixture was reacted for 1 hour, and 2.5 g of aqueous ammonia (30%) was added to stop the reaction. The reaction solution was crystallized and precipitated using 5 L of acetic acid water, and further washed twice with water. After filtration, it was dried under reduced pressure at 40 ° C. to obtain 47 g of a white polymer.

When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Hydroxystyrene: p-ethoxyethoxystyrene = 0.64: 0.36
Mass average molecular weight (Mw) = 13,000
Molecular weight distribution (Mw / Mn) = 1.10
This polymer compound is referred to as comparative polymer 2.

(Examples and comparative examples)
[Preparation of positive resist material]
The synthesized polymer compounds (Polymers 1 to 9, Comparative Polymers 1 and 2), acid generators (PAG1, PAG2) represented by the following formula, basic compounds (Amine1, Amine2, Amine3), dissolution inhibitors (DRI1, DRI2) was dissolved in an organic solvent with the composition shown in Table 1 to prepare a resist material, and each composition was filtered through a 0.2 μm size filter to prepare a positive resist material solution.

Each composition in Table 1 is as follows.
Polymers 1 to 9: From Synthesis Examples 1 to 9 Comparative Polymers 1 and 2: From Comparative Synthesis Examples 1 and 2

Acid generator: PAG1, PAG2 (see structural formula below)

Basic compounds: Amine1, Amine2, Amine3 (see structural formula below)

Dissolution inhibitor: DRI1, DRI2 (see structural formula below)

  Organic solvent: PGMEA (propylene glycol methyl ether acetate), EL (ethyl lactate)

[Electron beam drawing evaluation]
The above-prepared positive resist material ( Example 7, Reference Examples 1 to 6, 8 to 14, Comparative Examples 1 and 2) was placed on a 6-inch (150 mm) diameter Si substrate and clean track Mark 5 (manufactured by Tokyo Electron Ltd.). Was spin-coated on a hot plate at 110 ° C. for 90 seconds to prepare a 100 nm resist film. For this, drawing in a vacuum chamber was performed at an HV voltage of 50 keV using a Hitachi HL-800D.

Immediately after drawing, post-exposure baking (PEB) was performed for 90 seconds at 100 ° C. on a hot plate using a clean track Mark 5 (manufactured by Tokyo Electron), and paddle development was performed for 30 seconds with a 2.38 mass% TMAH aqueous solution. A positive pattern was obtained.
The obtained resist pattern was evaluated as follows.
The minimum dimension at the exposure amount for resolving 0.12 μm line and space at 1: 1 was taken as the resolution, and the edge roughness of 120 nm LS was measured by SEM.
Table 1 shows the results of resist composition, sensitivity and resolution in EB exposure.

表１の結果から、実施例７、参考例１〜６，８〜１４のレジスト材料は、比較例１、２のレジスト材料に比べて高解像力であることが確認できた。また、感度および露光後のパターン形状も良好であることがわかる。

From the results in Table 1, it was confirmed that the resist materials of Example 7 and Reference Examples 1 to 6, 8 to 14 had higher resolution than the resist materials of Comparative Examples 1 and 2. Moreover, it turns out that the sensitivity and the pattern shape after exposure are also favorable.

[Dry etching resistance evaluation]
In the dry etching resistance test, a polymer solution obtained by dissolving 2 g of each of the synthesized polymer compounds (Polymers 1 to 9, Comparative Polymers 1 and 2) in 10 g of PGMEA and filtering through a 0.2 μm size filter was spun onto a Si substrate. A film was formed with a coat to give a film having a thickness of 300 nm and evaluated under the following conditions.

Etching Test with CHF ₃ / CF ₄ Gas Using a dry etching apparatus TE-8500P manufactured by Tokyo Electron Ltd., the film thickness difference between the polymer films before and after etching was determined.
In this evaluation, a film having a small film thickness difference, that is, a film having a small etching rate is excellent in etching resistance.
Etching conditions are as shown below.
Chamber pressure 40.0Pa
RF power 1,000W
Gap 9mm
CHF ₃ gas flow rate 30ml / min
CF ₄ gas flow rate 30ml / min
Ar gas flow rate 100ml / min
60 sec
The results are shown in Table 2.

  From the results of Table 2, it was confirmed that the polymer compounds (Polymers 1 to 9) according to the present invention have higher dry etching resistance than Comparative Polymers 1 and 2.

The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

Claims (6)

It has at least a repeating unit of substituted hydroxystyrene represented by the following general formula (1) and a repeating unit of substituted hydroxyvinylnaphthalene, and a repeating unit having a sulfonium salt represented by the following general formula (3), and radical polymerization A high molecular compound characterized by the above.

(In the formula, R ^{1, R 3} is a hydrogen atom or a methyl group ^{independently,} R 2, ^{R 4} are independently hydrogen, an acetyl group, an alkyl group, or the following (A-2) -1'~ Any one of acid labile groups selected from (A-2) -5 ′ and (A-2) -7 ′ to (A-2) -19 ′ , and either one or both of R ² and R ⁴ Is an acid labile group, p and q are 1 or 2. a and b are 0 <a / (a + b) ≦ 0.90, 0.1 ≦ b / (a + b) <1, and c ′ is 0 <c ′ / (a + b + c ′) <1 R ⁷ is a hydrogen atom or a methyl group, R ⁸ is a phenylene group, —O—R ¹¹ —, or —C (═O) —Y—R. ^{In the case of} —O—R ¹¹ —, —C (═O) —YR ¹¹ —, R ¹¹ is bonded to the sulfur atom in the general formula (3), where Y is an oxygen atom or NH , ^{R 11} is charcoal Number 1-6 linear, branched or cyclic alkylene group, a phenylene group or alkenylene group, a carbonyl group, an ester group, which may contain an ether or hydroxyl group .R ^9, R ¹⁰ are the same Or a heterogeneous linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, which may contain a carbonyl group, an ester group or an ether group, or an aryl group having 6 to 12 carbon atoms, or a carbon number Represents an aralkyl group or a thiophenyl group of 7 to 20. X ⁻ represents a non-nucleophilic counter ion.)

  The polymer compound according to claim 1, wherein the polymer compound has a mass average molecular weight in the range of 1,000 to 500,000.   A positive resist material comprising the polymer compound according to claim 1 as a base resin.   4. The positive resist material according to claim 3, wherein the positive resist material is a chemically amplified resist material containing an acid generator.   The positive resist according to claim 3 or 4, wherein the positive resist material contains at least one of an organic solvent, a basic compound, a dissolution inhibitor, and a surfactant. Resist material.   At least a step of applying the positive resist material according to any one of claims 3 to 5 on the substrate, a step of exposing to high energy rays after the heat treatment, and development using a developer. A pattern forming method comprising the steps of: