KR101064921B1 - Positive resist composition, method of forming resist pattern, and method of forming resist pattern profile - Google Patents

Abstract

The present invention provides a positive photoresist composition for solving ultraviolet rays, in particular, a photoresist composition that solves the problems in the original performance improvement technique using micro-photofabrication using ArF excimer laser light. A method of forming a resist pattern and a method of forming a resist pattern profile is provided.

The composition contains a resin (A) in which all the repeating units are acryl units, have an alicyclic group, have no aromatic groups, and the solubility in the developing solution is improved by the action of an acid, and the acryl units and methacryl units as the repeating units, It is a positive resist composition containing resin (B) which improves the solubility to a developing solution by the action of the acid which does not have an aromatic group, and the compound (C) which generate | occur | produces an acid by irradiation of actinic light or a radiation.

Description

Positive resist composition, resist pattern formation method and resist pattern profile formation method {POSITIVE RESIST COMPOSITION, METHOD OF FORMING RESIST PATTERN, AND METHOD OF FORMING RESIST PATTERN PROFILE}

The present invention relates to a positive photoresist composition for microfabrication, a method of forming a resist pattern and a method of forming a resist pattern profile, such as a semiconductor device sensitive to far ultraviolet rays, and more particularly, to forming a positive resist composition for exposure to ultraviolet rays, a resist pattern And a method of forming a resist pattern profile.

In recent years, integrated circuits are increasingly increasing in density, and in the manufacture of semiconductor substrates such as ultra-LSIs, processing of ultra-fine patterns having line widths of less than half microns has been required. In order to satisfy this necessity, the wavelength of use of the exposure apparatus used in photolithography has become shorter and shorter, and the use of excimer laser light (XeCl, KrF, ArF, etc.) of short wavelengths has now been investigated.

There is a chemical amplification resist used for the pattern formation of lithography in this wavelength region.

As a photoresist composition for an ArF light source, a resin in which an alicyclic hydrocarbon moiety is introduced for the purpose of imparting dry etching resistance has been proposed.

The application of the resin in which the alicyclic hydrocarbon moiety is introduced as a photoresist composition is still inadequate, and improvement is desired. Among them, there was a problem of PEB time dependency in which a pattern obtained in accordance with a change in post-heating time after exposure fluctuates. Since the resist for semiconductors is used for various uses, it is desired to express a certain performance under any conditions. PEB time dependence is important from the viewpoint of maintaining the productivity of the device and improving the yield, and it is desired that the PEB time dependence is small.

Accordingly, an object of the present invention is to provide a positive photoresist composition, a method of forming a resist pattern, and a resist pattern profile that solve the problems in the above-described performance enhancing technology of micro photofabrication using far-infrared light, especially ArF excimer laser light. The present invention provides a positive photoresist composition for far-ultraviolet exposure, a method of forming a resist pattern, and a method of forming a resist pattern profile with little PEB time dependency.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining the constituent material of a positive chemical amplification resist composition, the present inventors discovered that the objective of this invention was achieved by the following structure, and came to this invention.

(1) Resin (A) in which all the repeating units are acrylic units, have an alicyclic group, have no aromatic groups, and have improved solubility in a developer by the action of an acid, and contain acryl units and methacryl units as repeating units. A positive resist composition which contains a resin (B) which does not have an aromatic group and improves the solubility to a developing solution by the action of an acid, and the compound (C) which generate | occur | produces an acid by irradiation of actinic light or a radiation.

(2) The positive resist composition as described in (1) whose ratio of the acryl unit of resin (B) is 20-80 mol% among all the repeating units.

(3) The positive resist composition according to (1) or (2), wherein the glass transition temperatures of the resin (A) and the resin (B) are all 120 ° C or higher.

(4) The positive resist composition according to (1) or (2), wherein the difference between the glass transition temperatures of the resin (A) and the resin (B) is less than 5 ° C.

(5) The positive resist composition according to (1) or (2), wherein at least one of the resin (A) and the resin (B) contains a repeating unit having a structure represented by the following general formula.

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates.

식중, R₁₁은 메틸기, 에틸기, n-프로필기, 이소프로필기, n-부틸기, 이소부틸기 또는 sec-부틸기를 나타내고, Z는 탄소원자와 함께 지환식 탄화수소기를 형성하는 데에 필요한 원자단을 나타낸다.
R₁₂~R₁₄는 각각 독립적으로 탄소수 1~4개의 알킬기, 또는 지환식 탄화수소기를 나타낸다. 단, R₁₂~R₁₄ 중 1개 이상은 지환식 탄화수소기를 나타낸다.
(8) (4)에 있어서, 수지(A) 및 수지(B) 중 하나 이상은 하기 일반식으로 표시되는 구조를 갖는 반복단위를 함유하는 것을 특징으로 하는 포지티브 레지스트 조성물.

식중, R₁₁은 메틸기, 에틸기, n-프로필기, 이소프로필기, n-부틸기, 이소부틸기 또는 sec-부틸기를 나타내고, Z는 탄소원자와 함께 지환식 탄화수소기를 형성하는 데에 필요한 원자단을 나타낸다.
R₁₂~R₁₄는 각각 독립적으로 탄소수 1~4개의 알킬기, 또는 지환식 탄화수소기를 나타낸다. 단, R₁₂~R₁₄ 중 1개 이상은 지환식 탄화수소기를 나타낸다.
(9) (6)에 있어서, 수지(A) 및 수지(B) 중 하나 이상은 하기 일반식으로 표시되는 구조를 갖는 반복단위를 함유하는 것을 특징으로 하는 포지티브 레지스트 조성물.

식중, R₁₁은 메틸기, 에틸기, n-프로필기, 이소프로필기, n-부틸기, 이소부틸기 또는 sec-부틸기를 나타내고, Z는 탄소원자와 함께 지환식 탄화수소기를 형성하는 데에 필요한 원자단을 나타낸다.
R₁₂~R₁₄는 각각 독립적으로 탄소수 1~4개의 알킬기, 또는 지환식 탄화수소기를 나타낸다. 단, R₁₂~R₁₄ 중 1개 이상은 지환식 탄화수소기를 나타낸다.
(10) (1) 또는 (2)에 기재된 포지티브 레지스트 조성물을 이용해서 기판 상에 적당한 도포방법으로 도포하여 레지스트막을 형성하고, 마스크를 통해 노광하고, 베이킹하여 현상하는 것을 포함하는 것을 특징으로 하는 레지스트 패턴의 형성방법.
(11) (10)에 있어서, 상기 기판에는 반사방지막이 형성되어 있는 것을 특징으로 하는 레지스트 패턴의 형성방법.
(12) (10)에 있어서, 상기 노광광은 파장이 150nm~250nm인 것을 특징으로 하는 레지스트 패턴의 형성방법.
(13) 반사방지막을 웨이퍼 상에 도포 건조한 후, 그 위에 (1) 또는 (2)에 기재된 포지티브 레지스트 조성물을 도포하고 건조하여 포지티브 레지스트막을 형성하고, 이것에 ArF 엑시머 레이저로 1/2 피치의 콘택트홀 패턴으로 노광한 후, 가열처리하고 현상하여 린스하는 것을 포함하는 것을 특징으로 하는 레지스트 패턴 프로파일의 형성방법.R ₁₂ to R ₁₄ each independently represent an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ represents an alicyclic hydrocarbon group.
(6) The positive resist composition as described in (3), wherein the difference between the glass transition temperatures of the resin (A) and the resin (B) is less than 5 ° C.
(7) The positive resist composition as described in (3), wherein at least one of the resin (A) and the resin (B) contains a repeating unit having a structure represented by the following general formula.

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates.
R ₁₂ to R ₁₄ each independently represent an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ represents an alicyclic hydrocarbon group.
(8) The positive resist composition as described in (4), wherein at least one of the resin (A) and the resin (B) contains a repeating unit having a structure represented by the following general formula.

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates.
R ₁₂ to R ₁₄ each independently represent an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ represents an alicyclic hydrocarbon group.
(9) The positive resist composition as described in (6), wherein at least one of the resin (A) and the resin (B) contains a repeating unit having a structure represented by the following general formula.

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates.
R ₁₂ to R ₁₄ each independently represent an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ represents an alicyclic hydrocarbon group.
(10) A resist comprising applying a positive resist composition as described in (1) or (2) to a substrate by a suitable coating method to form a resist film, exposing through a mask, baking and developing. How to form a pattern.
(11) The method for forming a resist pattern according to (10), wherein an antireflection film is formed on the substrate.
(12) The method for forming a resist pattern according to (10), wherein the exposure light has a wavelength of 150 nm to 250 nm.
(13) After the antireflection film is applied and dried on the wafer, the positive resist composition according to (1) or (2) is applied and dried thereon to form a positive resist film, and the ArF excimer laser has a half pitch contact thereon. A method of forming a resist pattern profile comprising exposure to a hole pattern, followed by heat treatment, development and rinsing.

Hereinafter, the component used for this invention is demonstrated in detail.

[1] resins having improved solubility in developers due to the action of acids

The resist composition of the present invention contains resins (A) and (B) as resins (acid-decomposable resins) whose solubility in a developing solution is enhanced by the action of an acid.

Resin (A) is an acid-decomposable resin in which all repeating units are acrylic units, have alicyclic groups, and no aromatic groups, and resin (B) contains acryl and methacrylic units as repeating units, and does not have aromatic groups. Resin.

Here, the acryl unit means a repeating unit formed from acrylic acid or an acrylic acid ester, and a methacrylic unit means a repeating unit formed from methacrylic acid or methacrylic acid ester.

The resins (A) and (B) do not have an aromatic group, wherein the aromatic group is a compound such as a benzene ring, naphthalene, anthracene, etc., and is a residue having a cyclic π electron cloud delocalized above and below the electron plane. Has a characteristic that 4 n + 2 (n is 0 or a natural number) of? Electrons in total are contained.

It is preferable that both the glass transition temperatures of resin (A) and resin (B) are 120 degreeC or more, and it is preferable that the difference of the glass transition temperature of resin (A) and resin (B) is less than 5 degreeC.

Although it does not specifically limit as alicyclic group which resin (A) has, What is demonstrated as alicyclic hydrocarbon group as R <_12> -R <_14> in Formula (pII) mentioned later is mentioned.

50 mol% or more of all the repeating units is preferable, and, as for content of the repeating unit which has an alicyclic group, 60 mol% or more is more preferable.

As for content of the repeating unit which has an acid-decomposable group, 20-70 mol% is preferable in all the repeating units, More preferably, it is 24-65 mol%, More preferably, it is 28-60 mol%.                     

As for the weight average molecular weight of resin (A), 3,000-100,000 are preferable as polystyrene conversion value by GPC method, More preferably, it is 4,000-50,000, More preferably, it is 5,000-30,000. If the weight average molecular weight is less than 3,000, it is not preferable because of deterioration of heat resistance or dry etching resistance, and if it exceeds 100,000, developability is deteriorated, or since the viscosity is very high, film forming property is deteriorated. There is a case.

Moreover, as dispersion degree (Mw / Mn) of resin (A), the range of 1.3-4.0 is preferable, More preferably, it is 1.4-3.8, More preferably, it is 1.5-3.5.

The repeating unit which comprises resin (B) consists only of an acryl unit and methacryl unit, 20-80 mol% of an acryl unit is preferable with respect to the repeating unit which comprises resin (B), and 30-70 mol% is more desirable.

As for the content rate of the repeating unit containing an acid-decomposable group in resin (B), 20-55 mol% is preferable as a total amount in all the repeating units, More preferably, it is 24-50 mol%, More preferably, it is 28-45 mol %to be.

As for the weight average molecular weight of resin (B), 3,000-100,000 are preferable as polystyrene conversion value by GPC method, More preferably, it is 4,000-50,000, More preferably, it is 5,000-30,000. If the weight average molecular weight is less than 3,000, it is not preferable because of deterioration of heat resistance or dry etching resistance, and if it exceeds 100,000, developability is deteriorated, or since the viscosity is very high, film forming property is deteriorated. do.                     

As dispersion degree (Mw / Mn) of resin (B), the range of 1.3-4.0 is preferable, More preferably, it is 1.4-3.8, More preferably, it is 1.5-3.5.

It is preferable that it is 100 degreeC or more, and, as for resin (A) and (B), it is more preferable that it is 120-180 degreeC.

It is preferable that at least one of resin (A) and (B) has a glass transition point of 120 degreeC or more.

It is preferable that the glass transition point of both resin (A) and (B) is 120 degreeC or more, and it is preferable that it is 130 degreeC or more from a process window, a density dependency, and a side lobe magin.

The glass transition temperature (Tg) of the resins (A) and (B) can be measured by a differential scanning calorimeter.

Resin (A) can obtain resin with a glass transition point of 110-170 degreeC by all repeating units being an acryl repeating unit, and containing the repeating unit which has alicyclic structure. In addition, a resin having a glass transition point of 110 to 170 ° C, preferably 130 to 160 ° C, is preferred in view of reducing the density dependency and improving the side lobe margin. The process window is also improved by using a resin having a high glass transition point.

In order to control a glass transition point within the said characteristic range, it is necessary not only to introduce the repeating unit which has an alicyclic structure, but also to control molecular weight and dispersion degree (Mw / Mn).

The weight average molecular weight of the resin (A) is usually 5,000 to 30,000, preferably 6,000 to 25,000, more preferably 7,000 to 20,000.                     

Dispersion degree of resin (A) is 3.5 or less normally, Preferably it is 3.0 or less, More preferably, it is 2.5 or less.

If the weight average molecular weight is less than 5,000 or the dispersion degree is more than 3.5, the Tg may be lowered and the performance may be degraded in terms of density dependency and side lobe margin.

In order to control the weight average molecular weight and the degree of dispersion, not only the above reaction conditions are selected, but also the dropwise polymerization method in which the reaction monomer solution and the solution of the radical polymerization initiator are added dropwise or separately added to a solvent heated to a constant temperature.

Moreover, the effect of this invention can be heightened further by removing the lower molecular weight among resin obtained by superposition | polymerization by the fractional reprecipitation method. The fractional reprecipitation method is a method of removing a low molecular weight oligomer having high solvent solubility by, for example, injecting a resin solution into a poor solvent of a resin or injecting a poor solvent of a resin into a resin solution.

As the poor solvent of the resin (A), a mixed solvent of a hydrocarbon solvent such as n-hexane, n-heptane and toluene, a hydrocarbon solvent and an ester solvent such as ethyl acetate, a single solvent or a mixed solvent of alcohols such as distilled water, methanol and ethanol Can be enumerated.

In addition, the said reaction solvent etc. can be used as a solvent which melt | dissolves resin. Here, the low molecular oligomer is, for example, a weight average molecular weight of 4,000 or less.

The addition ratio (mass ratio) ((A) / (B)) of the resins (A) and (B) is usually 3/97 to 90/10, preferably 5/95 to 85/15, and more preferably 10/90 ~ 80/20.                     

The total amount of resin (A) and (B) is 40-99.99 mass% normally with respect to the total solid of a composition, Preferably it is 50-99.97 mass%.

Hereinafter, although the repeating unit which resin (A) and (B) may contain is demonstrated, although acryl unit or methacryl unit may be sufficient about resin (B), it is limited to acryl unit about resin (A).

Resins (A) and (B) are both resins (acid-decomposable resins) in which the solubility in an alkali developer is improved by the action of an acid, and have groups (acid-decomposable groups) that are decomposed by the action of an acid and become alkali-soluble. Contains repeat units.

Resin (A) and (B) may contain the acid-decomposable group in any repeating unit.

As an acid-decomposable group, group represented by -COOA ^O , -OB ^O group can be mentioned. In addition, groups containing these include groups represented by -R ^O -COOA ⁰ or -Ar-OB ^O.

Where A ^O is -C (R ⁰¹ ) (R ⁰² ) (R ⁰³ ), -Si (R ⁰¹ ) (R ⁰² ) (R ⁰³ ), -C (R ⁰⁴ ) (R ⁰⁵ ) -OR ⁰⁶ or Lactone group is shown. B ^O represents an -A ^O or -CO-OA ^O group.

R ⁰¹ , R ⁰² , R ⁰³ , R ⁰⁴ and R ⁰⁵ may be the same or different, respectively, and represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group, and R ⁰⁶ represents an alkyl group or a cyclic alkyl group or an aryl group Indicates. However, two or more of R ⁰¹ to R ⁰³ may be a group other than a hydrogen atom, and two groups of R ⁰¹ to R ⁰³ and R ⁰⁴ to R ⁰⁶ may combine to form a ring. R ⁰ represents a divalent or higher aliphatic or aromatic hydrocarbon group which may have a single bond or a substituent, and -Ar- represents a divalent or higher aromatic group which may have a monocyclic or polycyclic substituent.

Here, the alkyl group is preferably one having 1 to 4 carbon atoms such as methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, and tert-butyl group, and cycloalkyl group is cyclopropyl group, cyclobutyl group, cyclohex. The C3-C30 thing, such as a real group and an adamantyl group, is preferable, As an alkenyl group, C2-C4 things, such as a vinyl group, a propenyl group, an allyl group, and a butenyl group, are preferable, and as an aryl group, a phenyl group and a xylyl group The C6-C14 thing like a toluyl group, cumenyl group, a naphthyl group, and anthracenyl group is preferable. Examples of the cyclic alkyl group include those having 3 to 30 carbon atoms, specifically, cyclopropyl group, cyclopentyl group, cyclohexyl group, adamantyl group, norbornyl group, boronyl group, tricyclodecanyl group, dicyclopentenyl group, and nord Boronepoxy group, menthyl group, isomentyl group, neomentyl group, tetracyclo dodecanyl group, a steroid residue, etc. can be mentioned. Examples of the aralkyl group include those having 7 to 20 carbon atoms and may have a substituent. Benzyl, phenethyl, cumyl and the like.

As the substituent, a hydroxy group, a halogen atom (fluorine, chlorine, bromine, iodine), a nitro group, a cyano group, the alkyl group, a methoxy group, an ethoxy group, a hydroxyethoxy group, a propoxy group, a hydroxypropoxy group, alkoxy groups such as alkoxy groups such as n-butoxy groups, isobutoxy groups, sec-butoxy groups, tert-butoxy groups, alkoxycarbonyl groups such as methoxycarbonyl groups and ethoxycarbonyl groups, and aralkyl groups such as benzyl groups, phenethyl groups and cumyl groups Acyl groups such as acyl groups such as aralkyloxy groups, formyl groups, acetyl groups, butyryl groups, benzoyl groups, cyanyl groups and valeryl groups, and acyloxy groups such as butyryloxy groups, the alkenyl groups, vinyloxy groups, propenyloxy groups, and the like. Alkenyloxy groups, such as an allyloxy group and a butenyloxy group, aryloxy groups, such as the said aryl group and a phenoxy group, and aryloxycarbonyl groups, such as a benzoyloxy group, are mentioned.

Moreover, the thing of the following structure is mentioned as said lactone group.

In said formula, R ^<a> , R <^b> , R <^c> represents a hydrogen atom and a C1-C4 alkyl group each independently. n represents the integer of 2-4.

When using an ArF excimer laser light as an exposure light source, it is preferable to use the group represented by -C (= O) -X ₁ -R ₀ as a group decomposed by the action of an acid. Here, as R ₀ , tertiary alkyl groups such as tert-butyl group and tert-amyl group, isoboroyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxyethyl group, 1-cyclohexyloxyethyl group, etc. Alkoxy methyl groups such as 1-alkoxyethyl group, 1-methoxymethyl group, 1-ethoxymethyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl group, 3-oxocyclohexyl group, and the lactone group can do. X ₁ represents an oxygen atom or a sulfur atom, but is preferably an oxygen atom.

It is preferable to contain the repeating unit represented by following General formula (1) which has an alicyclic hydrocarbon structure as a repeating unit which has an acid-decomposable group.

In general formula (I), R <_2> represents a hydrogen atom or a methyl group, A represents a single bond or a linking group, and ALG is a group containing alicyclic hydrocarbon represented by the following general formula (pI)-(pV). (However, when the resin (A) has a repeating unit represented by the general formula (I), R ₂ represents a hydrogen atom).

The linking group of A is an alkylene group, a substituted alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amido group, a sulfonamido group, a urethane group, or a combination of two or more groups selected from the group consisting of urea groups Indicates. As an alkylene group in said A, group represented by a following formula can be mentioned.

-[C (R _b ) (R _c )] _r-

In the formula, R _b and R _c represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxy group, or an alkoxy group, and both may be the same or different. The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably selected from methyl group, ethyl group, propyl group and isopropyl group. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group (preferably C1-C4) can be mentioned. As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, are mentioned. Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom. r represents the integer of 1-10.

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms. .

R <_12> -R <_16> respectively independently shows a C1-C4 linear or branched alkyl group or alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ and any one of R ₁₅ and R ₁₆ represent an alicyclic hydrocarbon group.

R ₁₇ to R ₂₁ each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R ₁₇ to R ₂₁ represents an alicyclic hydrocarbon group. In addition, any one of R <_19> , R <_21> represents a C1-C4 linear or branched alkyl group or alicyclic hydrocarbon group.

R ₂₂ to R ₂₅ each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R ₂₂ to R ₂₅ represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

In formulas (pI) to (pV), R ₁₂ to R ₂₅ As an alkyl group in this, any of substituted or unsubstituted may be sufficient, and a C1-C4 linear or branched alkyl group is shown. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group and the like.

Further, other substituents of the alkyl group include an alkoxy group having 1 to 4 carbon atoms, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), acyl group, acyloxy group, cyano group, hydroxy group, carboxyl group, alkoxycarbonyl group And nitro groups can be enumerated.

The alicyclic hydrocarbon group or the alicyclic hydrocarbon group formed by Z and a carbon atom in R ₁₁ to R ₂₅ may be monocyclic or polycyclic. Specifically, the group which has a C5 or more monocyclo, bicyclo, tricyclo, or tetracyclo structure can be enumerated. 6-30 are preferable and, as for the carbon number, 7-25 are especially preferable. These alicyclic hydrocarbon groups may have a substituent.

The structural example of the alicyclic site | part of an alicyclic hydrocarbon group is shown below.

In the present invention, preferred examples of the alicyclic moiety include an adamantyl group, noadamantyl group, decalin residue group, tricyclodecanyl group, tetracyclododecanyl group, norbornyl group, cedrol group, cyclohexyl group, cycloheptyl group, A cyclooctyl group, a cyclodecanyl group, and a cyclododecanyl group can be mentioned. More preferably, they are an adamantyl group, a decalin residue, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, a cyclododecanyl group, and a tricyclodecanyl group.

As a substituent of these alicyclic hydrocarbon groups, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxy group, and an alkoxycarbonyl group are mentioned.

The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably a substituent selected from the group consisting of methyl group, ethyl group, propyl group and isopropyl group.

As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group can be mentioned.

As said alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, can be mentioned.

Moreover, it is preferable that at least one of resin (A) and (B) is A is a single bond, and ALG contains the repeating unit represented by Formula (I) which is group represented by general formula (pI) or (pII). .

Moreover, the repeating unit in which A is a single bond in general formula (I) and ALG is shown below is especially preferable from the point that the variation of the pattern size at the time of observation with a scanning electron microscope is small (SEM tolerance).

R ₂₆ and R ₂₇ each independently represent a linear or branched alkyl group having 1 to 4 carbon atoms.

Hereinafter, the specific example of the monomer corresponded to the repeating unit represented by general formula (I) is shown.

In addition, it is preferable that resin (A) and (B) contain the repeating unit represented by general formula (II).

In general formula (II), R <_3> represents a hydrogen atom or a methyl group (however, when resin (A) has a repeating unit represented by general formula (II), R <_3> represents a hydrogen atom).

A ₃ represents a single bond or a divalent linking group.

Z ₃ represents a p + valent monovalent alicyclic hydrocarbon group.

p represents the integer of 1-3.

That is, -Z _3- (OH) p represents a group in which p hydroxyl groups are substituted with an alicyclic hydrocarbon group.

As a divalent linking group of A <_3>, the same thing as A in general formula (I) can be enumerated, and the same also about a preferable group.

As alicyclic hydrocarbon group of Z <_3>, the alicyclic hydrocarbon group as R <_11> -R <_25> with respect to ALG in General formula (I) can be mentioned, and the same also about a preferable group.

The p hydroxyl groups may be substituted with either of the alicyclic hydrocarbon group itself of Z ₃ and the substituent moiety which the alicyclic hydrocarbon has.

In addition, since a wide exposure margin is obtained at the time of forming a line pattern by under exposure, the repeating unit represented by the following general formula (IIa) is preferable as the repeating unit represented by the general formula (II).

In General Formula (IIa), R ₃₀ represents a hydrogen atom or a methyl group.

R ₃₁ to R ₃₃ each independently represent a hydrogen atom, a hydroxy group, or an alkyl group, provided that at least one represents a hydroxy group.

(However, when the resin (A) has a repeating unit represented by the general formula (IIa), R ₃₀ represents a hydrogen atom)

In forming the hole pattern by under exposure, it is more preferable that two of R ₃₁ to R ₃₃ are hydroxyl groups in the repeating unit represented by the general formula (IIa) in that a wide exposure margin is obtained.

Although the specific example of the repeating unit represented by general formula (II) is listed below, it is not limited to these.

It is preferable that resin (A) and (B) contain the repeating unit which has alicyclic lactone structure from the point which suppresses the hole deformation at the time of an etching.

As a repeating unit which has alicyclic lactone structure, the repeating unit which has cyclohexane lactone, norbornane lactone, or adamantane lactone can be mentioned, for example.

For example, as a repeating unit which has a norbornane lactone, as a repeating unit which has the (meth) acryl repeating unit which has a group represented by the following general formula (a-1)-(a-3), and a cyclohexane lactone, the following general formula As a (meth) acryl repeating unit which has a group represented by (a-4) and (a-5), and a repeating unit which has adamantane lactone, the (meth) acryl repeating unit which has a group represented by the following general formula (VI) Can be enumerated.                     

In particular, the (meth) acryl repeating unit which has group represented by either of the following general formula (a-1)-(a-3) is especially preferable.

In General Formulas (a-1) to (a-5), R ₁ to R ₆ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, or an alkenyl group. Two of R ₁ to R ₆ may be bonded to each other to form a ring.

In addition, the hydrogen atom with respect to each of R <_1> -R <_6> means unsubstituted. For example, the cyclic structure in general formula (a-1) may have up to 5 substituents (alkyl group, cycloalkyl group, or alkenyl group) as R <_1> -R <_5> .

The alkyl group as R ₁ to R ₆ may have a substituent and is a linear or branched alkyl group.

As a linear or branched alkyl group, a C1-C12 linear or branched alkyl group is preferable, More preferably, it is a C1-C10 linear or branched alkyl group, More preferably, a methyl group, an ethyl group, and a propyl group , Isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group and decyl group.

The cycloalkyl group as R ₁ to R ₆ may have a substituent, and preferably 3 to 8 carbon atoms such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group.

The alkenyl group as R ₁ to R ₆ may have a substituent, and preferably 2 to 6 carbon atoms such as vinyl group, propenyl group, butenyl group, hexenyl group and the like.

Moreover, as a ring formed by two of R <_1> -R <_6> bonding, 3-8 membered rings, such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, and a cyclooctane ring, are mentioned.

In addition, R <_1> -R <_6> in general formula (a-1)-(a-5) may be couple | bonded with either of the carbon atoms which comprise the cyclic skeleton.

Preferable substituents which the alkyl group, cycloalkyl group and alkenyl group may have include an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an acyl group having 2 to 5 carbon atoms, A C2-C5 acyloxy group, a cyano group, a hydroxyl group, a carboxy group, a C2-C5 alkoxycarbonyl group, a nitro group, etc. can be mentioned.

As a repeating unit which has group represented by general formula (a-1)-(a-5), the repeating unit represented by the following general formula (V) can be enumerated.

In formula (V), R _b0 represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, provided that the resin (A) has a repeating unit represented by the general formula (V). In which case R _bO represents a hydrogen atom).

As a preferable substituent which the alkyl group of R <_b0> may have, what was illustrated previously as a preferable substituent which the alkyl group as R <_1> in said general formula (a-1)-(a-5) may have is mentioned.

_Examples of the halogen atom for R _b0 include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R _b0 is preferably a hydrogen atom.

A 'represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or the bivalent group which combined these.

B ₂ represents a group represented by any one of General Formulas (a-1) to (a-5). As A 'the bivalent group combined above, the thing of the following formula is mentioned, for example.

In the above formula, R _ab , R _bb represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxy group, or an alkoxy group, and both may be the same or different.

The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably selected from methyl group, ethyl group, propyl group and isopropyl group. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and a C1-C4 alkoxy group can be mentioned.                     

As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, are mentioned.

Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom.

r1 is an integer of 1-10, Preferably the integer of 1-4 is represented. m represents an integer of 1 to 3, preferably 1 or 2.

Although the specific example of the repeating unit represented by general formula (V) is listed below, the content of this invention is not limited to these.

As a repeating unit which has adamantane lactone, the repeating unit represented by the following general formula (VI) can be enumerated.

In general formula (VI), A <_6> represents single or a combination of 2 or more groups chosen from the group which consists of a single bond, an alkylene group, a cycloalkylene group, an ether group, a thioether group, a carbonyl group, and an ester group.

R _6a represents a hydrogen atom, a 1-4C alkyl group, a cyano group or a halogen atom (however, when the resin (A) having a repeating unit represented by the following formula (VI) is R _6a represents characters of hydrogen) .

In general formula (VI), the group represented by a following formula can be mentioned as an alkylene group of A <_6> .

-{C (Rnf) (Rng)} r-

In the formula, Rnf and Rng represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxy group and an alkoxy group, and both may be the same or different. The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably selected from methyl group, ethyl group, propyl group and isopropyl group. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group can be mentioned. As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, are mentioned. Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom. r is an integer of 1-10.

In general formula (VI), a C3-C10 thing is mentioned as a cycloalkylene group of A <_6> , A cyclopentylene group, a cyclohexylene group, a cyclooctylene group, etc. can be mentioned.

The bridged alicyclic ring containing Z ₆ may have a substituent. Examples of the substituent include a halogen atom, an alkoxy group (preferably having 1 to 4 carbon atoms), an alkoxycarbonyl group (preferably having 1 to 5 carbon atoms), an acyl group (for example, a formyl group, a benzoyl group), an acyloxy group (e. g., propyl carbonyl group, benzoyl group), the alkyl group (preferably having 1 to 4) (such as a -CONHSO ₂ CH _3), carboxy group, a hydroxy group, an alkylsulfonyl nilsul sulfamoyl group are exemplified. In addition, the alkyl group as a substituent may be further substituted with a hydroxyl group, a halogen atom, an alkoxy group (preferably having 1 to 4 carbon atoms) or the like.

In general formula (VI), the oxygen atom of the ester group couple | bonded with A <_6> may be couple | bonded with any position of the carbon atom which comprises the Z ₆ containing cyclic bridge alicyclic ring structure.

Although the specific example of the repeating unit represented by general formula (VI) is listed below, it is not limited to these.

Resin (A) and (B) can further contain the repeating unit which has a lactone structure represented by the following general formula (IV).

In the general formula (Ⅳ), R _1a represents a hydrogen atom or a methyl group (if there is only the resin (A) having a repeating unit represented by the following formula (IV) is R _1a represents a hydrogen atom).

W ₁ represents a single bond or a combination of two or more groups selected from the group consisting of a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, and an ester group.

R _a1 , R _b1 , R _c1 , R _d1 and R _e1 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. m and n represent the integer of 0-3 each independently, and m + n is 2 or more and 6 or less.

Examples of the alkyl group having 1 to 4 carbon atoms of R _a1 to R _e1 include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group and tert-butyl group.

In the formula (IV), the alkylene groups of W ₁ may be exemplified groups represented by the following formula.

-{C (Rf) (Rg)} r _1-

In the formula, Rf and Rg represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxy group and an alkoxy group, and both may be the same or different.

The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably selected from methyl group, ethyl group, propyl group and isopropyl group. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group can be mentioned.                     

As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, are mentioned.

Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom.

r ₁ is an integer of 1-10.

Examples of the other substituent in the alkyl group include a carboxyl group, acyloxy group, cyano group, alkyl group, substituted alkyl group, halogen atom, hydroxy group, alkoxy group, substituted alkoxy group, acetylamido group, alkoxycarbonyl group and acyl group.

Here, as an alkyl group, lower alkyl groups, such as a methyl group, an ethyl group, a propyl group, isopropyl group, a butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclopentyl group, are mentioned. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group can be mentioned. As a substituent of a substituted alkoxy group, an alkoxy group etc. can be mentioned. As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, are mentioned. As acyloxy group, an acetoxy group etc. are mentioned. Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom.

Hereinafter, although the specific example of the monomer corresponded to the repeating unit represented by General formula (IV) is shown, it is not limited to these.

In the specific example of said general formula (IV), (IV-17)-(IV-36) are preferable at the point which an exposure margin becomes more favorable.

Other acrylates which may be contained by the resins (A) and (B) are preferably alkyl acrylates having 1 to 10 carbon atoms in the alkyl group, such as methyl acrylate, ethyl acrylate, propyl acrylate, amyl acryl. Latex, cyclohexyl acrylate, ethylhexyl acrylate, octyl acrylate, tert-octyl acrylate, chloroethyl acrylate, 2-hydroxyethyl acrylate, 2,2-dimethylhydroxypropyl acrylate, 5-hydroxy Pentyl acrylate, trimetholpropane monoacrylate, pentaerythritol monoacrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate and the like.

Other methacrylates which the resin (B) may contain are preferably alkyl methacrylates having 1 to 10 carbon atoms in the alkyl group, such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, iso Propyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, octyl methacrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate Methacrylate, 2,2-dimethyl-3-hydroxypropyl methacrylate, trimetholpropane monomethacrylate, pentaerythritol monomethacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate and the like. can do.

Resins (A) and (B) can be synthesized by conventional methods (eg, radical polymerization). For example, in a general synthesis method, monomer species are injected into the reaction vessel in a batch or in the middle of the reaction, and if necessary, a reaction solvent such as ethers such as tetrahydrofuran, 1,4-dioxane, diisopropyl ether, and methyl ethyl Ketones such as ketones and methyl isobutyl ketones, ester solvents such as ethyl acetate, or various monomers such as propylene glycol monomethyl ether acetate, which will be described later, are dissolved and homogenized, and then inert such as nitrogen or argon. The polymerization is initiated using a commercially available radical polymerization initiator (eg, azo initiator, peroxide, etc.) under a gas atmosphere as necessary. An initiator is added or divided and added as desired, and after completion of the reaction, it is added to a solvent to recover a desired polymer by a method such as powder or solid recovery. The reaction concentration is 20% by mass or more, preferably 30% by mass or more, and more preferably 40% by mass or more. Reaction temperature is 10-150 degreeC, Preferably it is 30-120 degreeC, More preferably, it is 50-100 degreeC.

As for the content rate of the acryl repeating unit which has an acid-decomposable group in resin (A), 20-70 mol% is preferable in all the repeating units, More preferably, it is 24-65 mol%, More preferably, it is 28-60 mol%.

As for the content rate of the acryl repeating unit represented by General formula (I), 20-70 mol% is preferable in all the repeating units, More preferably, it is 24-65 mol%, More preferably, it is 28-60 mol%.

As for the content rate of the acryl repeating unit represented by General formula (II), 20-70 mol% is preferable in all the repeating units, More preferably, it is 24-60 mol%, More preferably, it is 28-60 mol%.                     

As for the content rate of the acryl repeating unit which has alicyclic lactone structure, 5-60 mol% is preferable in all the repeating units, More preferably, it is 10-55 mol%, More preferably, it is 15-50 mol%.

The total amount of the three repeating units is usually 60 to 100 mol%, preferably 70 to 100 mol%, more preferably 80 to 100 mol% of all the repeating units.

As for content of the acryl repeating unit which has a lactone structure in a side chain, 5-60 mol% is preferable in all the repeating units, More preferably, it is 10-50 mol%, More preferably, it is 15-45 mol%.

As for the content rate of the repeating unit containing acid-decomposable groups, such as a (meth) acryl repeating unit represented by General formula (I), in resin (B), 20-55 mol% is preferable as a total amount in all the repeating units, More preferably, Is 24-50 mol%, More preferably, it is 28-45 mol%.

As for the content rate of the (meth) acryl repeating unit represented by General formula (II), 1-30 mol% is preferable in all the repeating units, More preferably, it is 5-25 mol%, More preferably, it is 10-20 mol%. .

As for content of the (meth) acryl repeating unit which has alicyclic lactone structure, 5-60 mol% is preferable in all the repeating units, More preferably, it is 10-55 mol%, More preferably, it is 15-50 mol%.

As for content of the (meth) acryl repeating unit which has a lactone structure in a side chain, 5-60 mol% is preferable in all the repeating units, More preferably, it is 10-50 mol%, More preferably, it is 15-45 mol%.

[2] compounds generating acids by irradiation with actinic radiation or radiation                     

The resist composition of this invention contains the compound (photoacid generator) which generate | occur | produces an acid by actinic light or radiation irradiation.

Photoacid generators used in the present invention include photoinitiators of photocationic polymerization, photoinitiators of photoradical polymerization, photochromic agents of pigments, photochromic agents or microresists, and the like. Preferably, g-rays, h-rays, i-rays, KrF excimer laser light), ArF excimer laser light, electron beams, X-rays, molecular beams or compounds that generate an acid by ion beams and mixtures thereof may be appropriately selected and used. .

In addition, other photoacid generators used in the present invention include onium salts such as diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenium salts and arsonium salts, organohalogen compounds, and organometallics. Photo-decomposed compounds generating sulfonic acid, such as organic halides, photoacid generators having o-nitrobenzyl-type protecting groups, iminosulfonates, disulfone compounds, diazoketo sulfones, diazodisulfone compounds, etc. Can be.

Moreover, the compound which introduce | transduced the group which generate | occur | produces an acid by these light, or a compound in the main chain or side chain of a polymer can be used.

In addition, VNR Pillai, Synthesis , (1), 1 (1980), A. Abad et al, Tetra hedron Lett. , (47), 4555 (1971), DHR Barton et al, J. Chem. Soc. (C), 329 (1970), U.S. Patent No. 3,779,778, European Patent No. 126,712 and the like can also be used compounds which generate an acid by light.

Other photoacid generators which are particularly effective in combination among the compounds which decompose upon irradiation with actinic light or radiation to generate an acid will be described below.

(1) An oxazole derivative represented by the following general formula (PAG1) substituted with a trihalomethyl group or an S-triazine derivative represented by the general formula (PAG2).

In the formula, R ²⁰¹ represents a substituted or unsubstituted aryl group, alkenyl group, and R ²⁰² represents a substituted or unsubstituted aryl group, alkenyl group, alkyl group, or -C (Y) ₃ . Y represents a chlorine atom or a bromine atom.

Although the following compounds can be enumerated specifically, it is not limited to these.

(2) An iodonium salt represented by the following general formula (PAG3) or a sulfonium salt represented by the general formula (PAG4).

In the formula, Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group.

R ²⁰³ , R ²⁰⁴ and R ²⁰⁵ each independently represent a substituted or unsubstituted alkyl group and an aryl group.

Z ^- represents a pair anion such as _{^{BF 4 -, AsF 6 -,}} PF 6 -, SbF 6 -, SiF 6 2-, ClO 4 -, CF 3 SO 3 - alkanoic acid anions, such as perfluoroalkyl, pentafluoropropane Condensed polynuclear aromatic sulfonic acid anions, anthraquinone sulfonic acid anions, sulfonic acid group-containing dyes and the like, such as benzene sulfonic acid anion and naphthalene-1-sulfonic acid anion, may be cited, but the present invention is not limited thereto.

In addition, two of R ²⁰³ , R ²⁰⁴ , and R ²⁰⁵ and Ar ¹ , Ar ² may be bonded via a single bond or a substituent, respectively.

Although the compound shown below is mentioned as a specific example, It is not limited to these.                     

In the above, Ph represents a phenyl group.

The onium salts represented by formulas (PAG3) and (PAG4) are known and can be synthesized by the methods described in, for example, US Pat. Nos. 2,807,648 and 4,247,473, Japanese Patent Application Publication No. 53-101,331.

(3) The disulfone derivative represented by the following general formula (PAG5) or the iminosulfonate derivative represented by the general formula (PAG6).

In the formula, Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group. R ²⁰⁶ represents a substituted or unsubstituted alkyl group or aryl group. A represents a substituted or unsubstituted alkylene group, alkenylene group, arylene group.

Although the compound shown below is mentioned as a specific example, It is not limited to these.

(4) Diazodisulfone derivative represented by the following general formula (PAG7).

Here, R represents a linear, branched or cyclic alkyl group or an aryl group which may be substituted.

Although the compound shown below is mentioned as a specific example, It is not limited to these.

The addition amount of these photo-acid generators is normally used in 0.01-30 mass% based on solid content in a composition, Preferably it is 0.3-20 mass%, More preferably, it is used in the range of 0.5-10 mass%.

If the amount of the photoacid generator is less than 0.001% by mass, the sensitivity tends to be lowered. If the amount of the photoacid generator is more than 30% by mass, the light absorption of the resist is too high, leading to deterioration of the profile and narrowing of process (especially baking) margins. have.

Moreover, in this invention, the compound which decomposes | disassembles by irradiation of actinic light or a radiation and produces sulfonic acid is preferable.

[3] additives, other

The positive resist composition of the present invention may further contain a surfactant, an organic basic compound, an acid-decomposable dissolution inhibiting compound, a dye, a plasticizer, a photosensitizer and a compound for promoting solubility in a developing solution, if necessary.

(a) surfactant

The positive resist composition of the present invention contains a surfactant, preferably a fluorine-based and / or silicon-based surfactant.

The positive resist composition of the present invention preferably contains any one or two or more of a fluorine-based surfactant, a silicon-based surfactant, and a surfactant containing both a fluorine atom and a silicon atom.

When the positive resist composition of the present invention contains the acid-decomposable resin and the surfactant, it is effective when the line width of the pattern is even thinner, and the development defect is further improved.

As these fluorine-based and / or silicone-based surfactants, for example, JP-A-62-36663, JP-A-61-226746, JP-A-61-226745, JP-A 62-170950, JP-A 63-34540 Japanese Patent Laid-Open No. 7-230165, Japanese Patent No. 8-62834, Japanese Patent No. 9-54432, Japanese Patent No. 9-5988, Japanese Patent Laid-Open No. 2002-277862, US Patent No. 5,405,720 Surfactants described in Nos. 5,360,692, 5,529,881, 5,296,330, 5,436,098, 5,576,143, 5,294,511 and 5,824,451 In addition, the following commercially available surfactant can also be used as it is.

Commercially available fluorine- and / or silicone-based surfactants that can be used include, for example, EFtop EF301, EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florad FC430, FC431 (manufactured by Sumitomo 3M Ltd.), Megafac F171, F173, F176 , F189, R08 from Dainippon Ink and Chemicals, Inc., Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 from Asahi Glass Co., Ltd., and Troysol S-366 from Troy Chemical Corp. product), such as a fluorine-type surfactant or silicone type surfactant. In addition, polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) may also be used as the silicone-based surfactant.

The fluorine- and / or silicon-based surfactants are also known as the telomerization method (also referred to as the "telomer method") or the oligomerization method (also referred to as the "oligomer method") in addition to those known above. Surfactants using a polymer having a fluoroaliphatic group derived from a fluoroaliphatic compound prepared by &lt; RTI ID = 0.0 &gt; A fluoroaliphatic compound can be synthesize | combined by the method of Unexamined-Japanese-Patent No. 2002-90991.

As the polymer having a fluorinated aliphatic group, a copolymer of a monomer having a fluorinated aliphatic group with (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferably distributed irregularly. It may be good or a block copolymer may be sufficient. Examples of the poly (oxyalkylene) group include poly (oxyethylene) groups, poly (oxypropylene) groups, poly (oxybutylene) groups and the like, and poly (oxyethylene-oxypropylene-oxyethylene block connectors). Or a unit having an alkylene having a different chain length in the same chain length, such as a poly (oxyethylene-oxypropylene block linker) group. The copolymer of a monomer having a fluoroaliphatic group and a (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer, but also a monomer having two or more different fluoroaliphatic groups or another two or more ( It may be a three-membered or more copolymer obtained by simultaneously copolymerizing poly (oxyalkylene)) acrylate (or methacrylate).

For example, commercially available fluorine-based and / or silicon-based surfactants may include Megafac F178, F-470, F-473, F-475, F-476, and F-472 (manufactured by Dainippon Ink and Chemicals, Inc.). . Further, copolymers of acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), acrylate (or methacrylate having a C ₆ F ₁₃ group) ), A copolymer of (poly (oxyethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate), an acrylate (or methacrylate having a C ₈ F ₁₇ group) ) And a copolymer of (poly (oxyalkylene)) acrylate (or methacrylate), acrylate (or methacrylate) having a C ₈ F ₁₇ group, (poly (oxyethylene)) acrylate (or methacrylate And copolymers of (poly (oxypropylene)) acrylate (or methacrylate) and the like.

The amount of the surfactant used is preferably 0.0001 to 2% by mass, more preferably 0.001 to 1% by mass, particularly preferably 0.01 to 1% by mass, based on the total amount of the positive resist composition (excluding the solvent).

As surfactants which can be used other than the above, specifically, polyoxyethylene alkyl ethers, such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, and polyoxy Polyoxyethylene alkylallyl ethers such as ethylene octyl phenol ether and polyoxyethylene nonylphenol ether, polyoxyethylene polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate Sorbitan fatty acid esters such as sorbitan monooleate, sorbitan trioleate, sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan mono Stearate, Polyoxyethylene Sorbitan Triole Agent, polyoxyethylene can be exemplified such as sorbitan tristearate, etc., polyoxyethylene sorbitan fatty acid non-ionic surfactants such as esters.

(b) organic basic compounds

It is preferable that the positive resist composition of this invention contains an organic basic compound. Preferable organic basic compounds are compounds which are more basic than phenol. Especially, a nitrogen-containing basic compound is preferable and the structure represented, for example by following (A)-(E) is mentioned.

Where R ²⁵⁰ , R ²⁵¹ and R ²⁵² each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aminoalkyl group having 1 to 6 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, Here, R ²⁵¹ and R ²⁵² may combine with each other to form a ring.

In formula, R <^253> , R <^254> , R <^255> and R <^256> represent a C1-C6 alkyl group each independently.

More preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms in different chemical environments in one molecule, particularly preferably compounds containing both substituted or unsubstituted amino groups and ring structures containing nitrogen atoms or alkylamino groups It is a compound which has. Preferred embodiments include substituted or unsubstituted guanidine, substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazole, substituted or unsubstituted Substituted pyrazole, substituted or unsubstituted pyrazine, substituted or unsubstituted pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted pipepe Razine, substituted or unsubstituted aminomorpholine, substituted or unsubstituted aminoalkylmorpholine, and the like. Preferred substituents are amino group, aminoalkyl group, alkylamino group, aminoaryl group, arylamino group, alkyl group, alkoxy group, acyl group, acyloxy group, aryl group, aryloxy group, nitro group, hydroxy group, cyano group.

Preferred embodiments of the nitrogen-containing basic compound include guanidine, 1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylamino Pyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2- (aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-6-methylpyridine, 3-aminoethylpyridine, 4-aminoethylpyridine, 3-aminopyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2-aminoethyl) Piperidine, 4-amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-aminoethyl) pyrrolidine, Pyrazole, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1-p-tolylpyrazole, pyrazine, 2- (aminomethyl) -5-methylpyrazine, pyrimidine, 2,4- Diaminopyrimidine, 4,6-dihydroxypyrimidine, 2-pyrazoline, 3-pyrazole , N-aminomorpholine, N- (2-aminoethyl) morpholine, 1,5-diazabicyclo [4.3.0] nona-5-ene, 1,8-diazabicyclo [5.4.0] undeca -7-ene, 1,4-diazabicyclo [2.2.2] octane, 2,4,5-triphenylimidazole, N-methylmorpholine, N-ethylmorpholine, N-hydroxyethylmorpholine , Tertiary morpholine derivatives such as N-benzyl morpholine, cyclohexyl morpholinoethylthiourea (CHMETU), and hindered amines described in Japanese Patent Application Laid-Open No. 11-52575 (for example, those described in the above publication). ), But are not limited to these.

Particularly preferred embodiments are 1,5-diazabicyclo [4.3.0] nona-5-ene, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,4-diazabicyclo [ 2.2.2] tertiary moles such as octane, 4-dimethylaminopyridine, hexanemethylenetetramine, 4,4-dimethylimidazoline, pyrroles, pyrazoles, imidazoles, pyridazines, pyrimidines and CHMETU Hindered amines such as porins, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, N, N-dihydroxyethylaniline, N, N-dibutylaniline, Trioctylamine, triphenylimidazole, antipyrine, 2,6-diisopropylaniline, and the like.

Among them, 1,5-diazabicyclo [4.3.0] nona-5-ene and 1,8-diazabicyclo [5. 4.0] undec-7-ene, 1,4-diazabicyclo [2.2.2] octane, 4-dimethylaminopyridine, hexamethylenetetramine, CHMETU, bis (1,2,2,6,6-pentamethyl 4-piperidyl) sebacate, N, N-dihydroxyethylaniline, N, N-dibutylaniline, trioctylamine, triphenylimidazole, antipyrine, 2,6-diisopropylaniline are preferred Do.

These nitrogen-containing basic compounds are used alone or in combination of two or more thereof. The usage-amount of a nitrogen-containing basic compound is 0.001-10 mass% normally with respect to solid content of the whole composition of the resist composition of this invention, Preferably it is 0.01-5 mass%. If it is less than 0.001 mass%, the addition effect of the said nitrogen-containing basic compound is not acquired. On the other hand, when it exceeds 10 mass%, there exists a tendency for the fall of a sensitivity and the developability of a non-exposed part to deteriorate.

[4] solvents

The positive resist composition of this invention is melt | dissolved in the solvent which melt | dissolves each said component, and apply | coats on a support body. The solvent used here is ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxy Ethyl acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), ethylene carbonate, toluene, ethyl acetate, butyl acetate, methyl lactate ethyl lactate, methyl methoxy Propionate, ethylethoxypropionate, methylpyruvate, ethylpyruvate, propylpyruvate, N, N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran and the like are preferable, These solvents are used individually or in mixture.

Among the above, preferred solvents include propylene glycol monomethyl ether acetate, 2-heptanone, γ-butyrolactone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, Propylene glycol monoethyl ether, ethylene carbonate, butyl acetate, methyl lactate, ethyl lactate, methyl methoxy propionate, ethyl ethoxy propionate, N-methylpyrrolidone and tetrahydrofuran.

It is preferable that it is 3-25 mass% as whole solid content concentration, as for the resist composition prepared by melt | dissolving each component in the solvent, it is more preferable that it is 5-20 mass%, and it is still more preferable that it is 7-20 mass%.

Such a positive resist composition of the present invention is applied onto a substrate to form a thin film. As for the thickness of this coating film, 0.2-1.2 micrometers is preferable.

Examples of the substrate that can be used include a BareSi substrate, an SOG substrate, or a substrate having an inorganic antireflection film described below.                     

In addition, a commercially available inorganic or organic antireflection film can be used as necessary.

As the anti-reflection film, an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, α-silicon, etc., and an organic film type made of a light absorber and a polymer material may be used. The former requires equipment such as a vacuum deposition apparatus, a CVD apparatus, a sputtering apparatus, etc. to form the film. As the organic antireflection film, for example, a condensation product of a diphenylamine derivative described in Japanese Patent Publication No. Hei 7-69611 and a formaldehyde-modified melamine resin, an alkali-soluble resin, a light absorber, and maleic anhydride described in US Pat. No. 5,294,680 A reaction product of a copolymer with a diamine type light absorber, a resin binder described in Japanese Patent Application Laid-Open No. 6-118631, a metharolmelamine-based thermal crosslinking agent, a carbonic acid group, an epoxy group, and a light absorber described in Japanese Patent Application Laid-open No. Hei 6-118656. An acrylic resin antireflective film having the same molecule, a monomer consisting of methirolmelamine described in Japanese Patent Application Laid-Open No. Hei 8-87115 and a benzophenone light absorber, and a low molecular light absorber in the polyvinyl alcohol resin described in Japanese Patent Application Laid-Open No. Hei 8-179509 And the like are added.

As the organic antireflection film, DUV-30 series, DUV-40 series, ARC 25, AC-2, AC-3, AR 19, AR 20, etc., manufactured by Brewer Science, can be used.

The resist liquid is applied onto a substrate (e.g., silicon / silicon dioxide coating) used in the manufacture of a precision integrated circuit device (if necessary, on a substrate on which the antireflection film is formed) by a suitable coating method such as a spinner, a coater, or the like. Subsequently, a good resist pattern can be obtained by exposing through a predetermined mask, baking and developing. As exposure light here, Preferably it is wavelength light of 150-250 nm. Specifically, KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157 nm), an X-ray, an electron beam, etc. are mentioned.

As the developing solution, inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate and ammonia water, first amines such as ethylamine and n-propylamine, diethylamine, di-n-butylamine and the like Tertiary ammonium salts such as secondary amines, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide, and pyrrole And alkaline aqueous solutions (usually 0.1-10 mass%), such as cyclic amines, such as piperidine, can be used.

Moreover, alcohol and surfactant can be added to the alkaline aqueous solution in an appropriate amount.

Example

Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example.

In the following synthesis examples, unless otherwise specified, the ratios and% refer to mass ratios and mass%.

Synthesis Example (1) Synthesis of Resin (A-1-1)

2-adamantyl-2-propyl acrylate, 3,5-dihydroxy-1-adamantyl acrylate, norbornanelactone acrylate were injected at a ratio of 40/20/40, and propylene glycol monomethyl It dissolved in ether acetate / propylene glycol monomethyl ether = 60/40, and prepared 450 g of solution of 22% of solid content concentration. Wako Pure Chemical Industries, Ltd. 1 mol% of V-601 of the product was added, and this was dripped at 50 g of the mixed solution of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 heated at 80 degreeC over 6 hours under nitrogen atmosphere. After completion of the dropwise addition, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized with 5 L of a mixed solvent of hexane / ethyl acetate = 7/3, and the precipitated white powder was collected by filtration to recover the target resin (A-1-1).

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 40/21/39. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 9,200, and dispersion degree was 1.9. Moreover, the glass transition point of resin (A-1-1) was 130 degreeC as a result of measuring by DSC (display scanning calorimeter).

Synthesis Example (2) Synthesis of Resin (A-1-2)

10 g of resin (A-1-1) was stirred and dissolved in 100 mL of tetrahydrofuran, and 90 mL of heptane was added thereto. After stirring for 1 hour, the upper layer was discarded, and the viscous substance precipitated below was precipitated, and the white powder was collected by filtration to recover the target resin (A-1-2).

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 39/21/40. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 10,370, and dispersion degree was 1.7. Moreover, as a result of DSC measurement, the glass transition point of resin (A-1-2) was 152 degreeC.

Synthesis Example (3) Synthesis of Resin (A-2-1)

Polymerization was carried out in the same manner as in Synthesis Example (1) to synthesize resin (A-2), and the obtained resin (A-2) was further subjected to solvent differentiation in the same manner as in Synthesis Example (2) to obtain resin (A-). 2-1) was obtained.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 38/21/41. In addition, the weight average molecular weight of the standard polystyrene conversion determined by GPC measurement was 11,130, and the dispersion degree was 1.7. Moreover, as a result of DSC measurement, the glass transition point of resin (A-2-1) was 146 degreeC.

Synthesis Example (4) Synthesis of Resin (A-3-1)

Polymerization was carried out in the same manner as in Synthesis Example (1) to synthesize resin (A-3), and the obtained resin (A-3) was further subjected to solvent differentiation in the same manner as in Synthesis Example (2) to obtain resin (A-). 3-1) was obtained.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 42/21/37. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 12,080, and dispersion degree was 1.6. Moreover, as a result of DSC measurement, the glass transition point of resin (A-3-1) was 142 degreeC.

Synthesis Example (5) Synthesis of Resin (A-4-1)

The polymerization was carried out in the same manner as in Synthesis Example (1) to synthesize Resin (A-4), and the obtained resin (A-4) was further subjected to solvent differentiation in the same manner as in Synthesis Example (2) to obtain resin (A-). 4-1) was obtained.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 38/22/40. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 10,740, and dispersion degree was 1.7. Moreover, as a result of DSC measurement, the glass transition point of resin (A-4-1) was 127 degreeC.

Synthesis Example (6) Synthesis of Resin (A-5-1)

Polymerization was carried out in the same manner as in Synthesis Example (1) to synthesize resin (A-5), and the obtained resin (A-5) was further subjected to solvent differentiation in the same manner as in Synthesis Example (2) to obtain resin (A-). 5-1) was obtained.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 42/21/37. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 10,210, and dispersion degree was 1.7. Moreover, as a result of DSC measurement, the glass transition point of resin (A-5-1) was 124 degreeC.

Synthesis Example (7) Synthesis of Resin (A-6-1)

Polymerization was carried out in the same manner as in Synthesis Example (1) to synthesize resin (A-6), and the obtained resin (A-6) was further subjected to solvent differentiation in the same manner as in Synthesis Example (2) to obtain resin (A-). 6-1).

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 38/29/23. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 11,990, and dispersion degree was 1.6. Moreover, as a result of DSC measurement, the glass transition point of resin (A-6-1) was 141 degreeC.

Synthesis Example (8) Synthesis of Resin (A-7-1)

Polymerization was carried out in the same manner as in Synthesis Example (1) to synthesize resin (A-7), and the obtained resin (A-7) was further subjected to solvent differentiation in the same manner as in Synthesis Example (2) to obtain resin (A-). 7-1).

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c / d = 31/20/39/10. In addition, the weight average molecular weight of the standard polystyrene conversion determined by GPC measurement was 11,340, and the dispersion degree was 1.7. Moreover, as a result of DSC measurement, the glass transition point of resin (A-7-1) was 155 degreeC.

Synthesis Example (9) Synthesis of Resin (A-8-1)

Polymerization was carried out in the same manner as in Synthesis Example (1) to synthesize resin (A-8), and the obtained resin (A-8) was further subjected to solvent differentiation in the same manner as in Synthesis Example (2) to obtain resin (A-). 8-1).

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 44/21/35. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 10,890, and dispersion degree was 1.8. Moreover, as a result of DSC measurement, the glass transition point of resin (A-8-1) was 136 degreeC.

Synthesis Example (10) Synthesis of Resin (A-9-1)

Polymerization was carried out in the same manner as in Synthesis Example (1) to synthesize resin (A-9), and the obtained resin (A-9) was further subjected to solvent differentiation in the same manner as in Synthesis Example (2) to obtain resin (A-). 9-1).

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 41/21/38. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 10,730, and dispersion degree was 1.9. Moreover, as a result of DSC measurement, the glass transition point of resin (A-9-1) was 153 degreeC.

Synthesis Example (11) Synthesis of Resin (A-10-1)

Polymerization was carried out in the same manner as in Synthesis Example (1) to synthesize resin (A-10), and the obtained resin (A-10) was further subjected to solvent differentiation in the same manner as in Synthesis Example (2) to obtain resin (A-). 10-1) was obtained.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 41/21/38. In addition, the weight average molecular weight of the standard polystyrene conversion calculated by GPC measurement was 11,070, and the dispersion degree was 1.8. Moreover, as a result of DSC measurement, the glass transition point of resin (A-10-1) was 145 degreeC.

Synthesis Example (12) Synthesis of Resin (B-1-1)

2-ethyl-2-adamantyl methacrylate, 3-hydroxy-1-adamantyl acrylate and norbornanelactone acrylate were injected at a ratio of 40/25/35, and propylene glycol mono methyl ether acetate It dissolved in / propylene glycol monomethyl ether = 60/40, and 450g of solution of 22% of solid content concentration was prepared. Wako Pure Chemical Industries, Ltd. 2 mol% of V-601 of the product was added, and it was dripped at 50 g of the mixed solution of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 70/30 heated at 80 degreeC over 8 hours under nitrogen atmosphere. After completion of the dropwise addition, the reaction solution was stirred for 1 hour. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized with 5 L of heptane, and the precipitated white powder was collected by filtration to recover resin (B-1-1) as a target product.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 38/26/36. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 8,600, and dispersion degree was 2.2. Moreover, as a result of DSC measurement, the glass transition point of resin (B-1-1) was 156 degreeC.

Synthesis Example (13) Synthesis of Resin (B-2-1)

2-adamantyl-2-propyl methacrylate, 3,5-dihydroxy-1-adamantyl acrylate, norbornanelactone acrylate were injected at a ratio of 40/20/40, and propylene glycol mono It melt | dissolved in methyl ether acetate / propylene glycol monomethyl ether = 70/30, and prepared 450 g of solutions of 22% of solid content concentration. Wako Pure Chemical Industries, Ltd. 4 mol% of V-601 of the product was added, and this was dripped at 50 g of the mixed solution of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether 60/40 heated at 80 degreeC over 6 hours in nitrogen atmosphere. After completion of the dropwise addition, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized with 5 L of a mixed solvent of hexane / ethyl acetate = 1/9, and the precipitated white powder was collected by filtration to recover the target resin (B-2-1).

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 42/20/38. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 7,900, and dispersion degree was 2.1. Moreover, as a result of DSC measurement, the glass transition point of resin (B-2-1) was 163 degreeC.

Synthesis Example (14) Synthesis of Resin (B-3-1)

The polymerization was carried out in the same manner as in Synthesis Example (13) to obtain Resin (B-3-1) as a target product.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 41/21/38. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 9,100, and dispersion degree was 2.2. Moreover, as a result of DSC measurement, the glass transition point of resin (B-3-1) was 153 degreeC.

Synthesis Example (15) Synthesis of Resin (B-3-1)

The polymerization was carried out in the same manner as in Synthesis Example (13) to obtain Resin (B-4-1) as a target product.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 48/22/30. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 8,200, and dispersion degree was 2.3. Moreover, as a result of DSC measurement, the glass transition point of resin (B-4-1) was 169 degreeC.

Synthesis Example (16) Synthesis of Resin (B-5-1)

The polymerization was carried out in the same manner as in Synthesis Example (12) to obtain Resin (B-5-1) as a target product.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 36/33/31. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 9,400, and dispersion degree was 2.4. Moreover, as a result of DSC measurement, the glass transition point of resin (B-5-1) was 137 degreeC.

Synthesis Example (17) Synthesis of Resin (B-6-1)

The polymerization was carried out in the same manner as in Synthesis Example (12) to obtain Resin (B-6-1) as a target product.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 41/20/39. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 8,900, and dispersion degree was 2.2. Moreover, as a result of DSC measurement, the glass transition point of resin (B-6-1) was 150 degreeC.

Synthesis Example (18) Synthesis of Resin (B-7-1)

The polymerization was carried out in the same manner as in Synthesis Example (13) to obtain Resin (B-7-1) as a target product.                     

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 48/23/29. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 9,700, and dispersion degree was 2.5. Moreover, as a result of DSC measurement, the glass transition point of resin (B-7-1) was 163 degreeC.

Synthesis Example (19) Synthesis of Resin (B-8-1)

The polymerization was carried out in the same manner as in Synthesis Example (13) to obtain Resin (B-8-1) as a target product.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c / d = 32/19/39/10. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 7,500, and dispersion degree was 1.9. Moreover, as a result of DSC measurement, the glass transition point of resin (B-8-1) was 161 degreeC.

Synthesis Example (20) Synthesis of Resin (B-9-1)

The polymerization was carried out in the same manner as in Synthesis Example (13) to obtain Resin (B-9-1) as a target product.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c / d = 20/20/21/39. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 8,100, and dispersion degree was 2.0. Moreover, as a result of DSC measurement, the glass transition point of resin (B-9-1) was 157 degreeC.

Synthesis Example (21) Synthesis of Resin (B-10-1)

The polymerization was carried out in the same manner as in Synthesis Example (13) to obtain Resin (B-10-1) as a target product.

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c / d = 38/21/36/5. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 8,100, and dispersion degree was 2.0. Moreover, as a result of DSC measurement, the glass transition point of resin (B-10-1) was 137 degreeC.

Examples 1-20 and Comparative Examples 1 and 2

Preparation and Evaluation of Positive Resist Composition

As shown in Table 1, a resin (2 g) synthesized in the above synthesis example, a photoacid generator (the compounding amount is shown in Table 1), an organic basic compound (4 mg), and a surfactant (10 mg) were blended if necessary, and the solid content After melt | dissolving with the solvent shown in Table 1 so that it may become 11 mass%, it filtered by the 0.1 micrometer microfilter, and produced the positive resist composition of Examples 1-20 and Comparative Examples 1 and 2. In addition, the ratio at the time of using plural about each component in Table 1 is a mass ratio.

Suzy
(A) Suzy
(B) Mixing ratio
(Mass ratio) Acid Generator (PAG) Basic
compound Interface
Active agent solvent
(Mass ratio) SB / PEB
(℃) Example 1 1-1 1-1 25/75 4-6 = 45mg 2 5 S1 / S2 = 60/40 115/115 Example 2 1-2 1-1 40/60 4-36 = 40mg 2 5 S1 / S2 = 60/40 115/115 Example 3 1-2 2-1 30/70 4-36 = 40mg 2 5 S1 / S4 = 60/40 115/115 Example 4 2-1 3-1 50/50 4-48 = 42mg 2 5 S1 / S4 = 60/40 115/115 Example 5 3-1 4-1 20/80 4-36 = 40mg 2 5 S1 / S2 = 60/40 130/130 Example 6 4-1 5-1 25/75 4-48 / 4-65 = 20 / 35mg 2 5 S1 / S2 = 60/40 125/120 Example 7 5-1 6-1 70/30 4-36 / 4-63 = 25 / 30mg 1/2 = 1/1 5 S1 / S4 = 60/40 120/120 Example 8 6-1 6-1 35/65 4-52 = 40mg 1/6 = 1/1 4 S1 / S4 = 60/40 115/115 Example 9 7-1 1-1 20/80 4-52 = 40mg 3 3 S4 / S3 = 95/5 115/115 Example 10 7-1 9-1 15/85 4-70 = 80mg 3 2 S4 / S3 = 95/5 115/115 Example 11 3-1 7-1 60/40 4-48 / 4-80 = 20 / 25mg 4 One S5 / S6 = 60/40 130/130 Example 12 8-1 7-1 75/25 4-36 / 4-96 = 40 / 2mg 5 5 S1 / S4 = 60/40 130/130 Example 13 9-1 8-1 30/70 4-50 / 7-3 = 42 / 3mg 1/2 = 1/1 5 S1 / S2 = 60/40 115/115 Example 14 9-1 9-1 15/85 4-36 / 4-78 = 41 / 3mg 5 5 S4 / S3 = 95/5 115/115 Example 15 10-1 7-1 35/65 4-50 = 45mg 3 5 S1 / S2 = 60/40 135/135 Example 16 8-1 10-1 20/80 4-6 = 46mg 4/5 = 1/1 5 S1 / S5 = 60/40 120/120 Example 17 1-2 1-1 85/15 4-36 = 40mg 2 5 S1 / S2 = 60/40 115/115 Example 18 1-2 1-1 20/80 4-36 = 40mg 2 5 S1 / S2 = 60/40 115/115 Example 19 3-1 4-1 45/55 4-36 = 40mg 2 5 S1 / S2 = 60/40 130/130 Example 20 3-1 4-1 90/10 4-36 = 40mg 2 5 S1 / S2 = 60/40 130/130 Comparative Example 1 3-1 100/0 4-36 = 40mg 2 5 S1 / S2 = 60/40 130/130 Comparative Example 2 4-1 0/100 4-36 = 40mg 2 5 S1 / S2 = 60/40 130/130

The symbol of each component in Table 1 shows the following.                     

[Acid generator]

Symbols in Table 1 correspond to specific examples of the acid generator (PAG) exemplified above.

[Surfactants]

1: Megafac F176 (Dainippon Ink and Chemicals, Inc.) (fluorine-based)

2: Megafac R08 (Dainippon Ink and Chemicals, Inc.) (fluorine and silicon-based)

3: polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.)

4: polyoxyethylene nonyl phenyl ether

5: Troysol S-366 (manufactured by Troy Chemical)

[Basic compound]

1: N, N-dihydroxyethylaniline

2: N, N-dibutylaniline

3: trioctylamine

4: triphenylimidazole

5: antipyrine

6: 2,6-diisopropylaniline

.

[solvent]

S1: Propylene Glycol Monomethyl Ether Acetate

S2: Propylene Glycol Monomethyl Ether                     

S3: γ-butyrolactone

S4: cyclohexanone

S5: ethyl lactate

S6: Butyl Acetate

(Assessment Methods)

First of all, Brewer Science Inc. The ARC-29A-8 of the product was coated on a silicon wafer using a spin coater at 78 nm, dried, and then the positive photoresist composition obtained thereon was applied, dried at a temperature (SB) shown in Table 1 for 90 seconds, and about 0.3 A positive resist film of 탆 was formed and exposed to this by an ArF excimer laser (wavelength: 193 nm, an ArF stepper manufactured by ISI of NA: 0.6) with a contact hole pattern (mask size of 0.18 탆) of 1/2 pitch. The post-exposure heat treatment was performed at the temperature (PEB) shown in Table 1 for 90 seconds, developed with a 2.38% by mass tetramethylammonium hydroxide aqueous solution, rinsed with distilled water to obtain a resist pattern profile.

[PEB time dependency]

Exposure hole pattern having a mask size of 0.18 μm is exposed, post-heating is performed by changing the time to 45 seconds and 90 seconds, and the exposure doses (E ₄₅ and E ₉₀₎ that 0.14 μm is reproduced by observing the pattern formed after development with a scanning electron microscope. ) Was measured, and it calculated by the following formula | equation. The smaller the obtained value is, the more preferable.

PEB time dependence = (| E ₄₅ -E ₉₀ | / E ₉₀ ) × 100)

The results are shown in Table 2.

PEB time dependency (%) Example 1 20 Example 2 7 Example 3 13 Example 4 12 Example 5 20 Example 6 13 Example 7 19 Example 8 12 Example 9 7 Example 10 6 Example 11 18 Example 12 21 Example 13 10 Example 14 7 Example 15 17 Example 16 7 Example 17 11 Example 18 8 Example 19 22 Example 20 28 Comparative Example 1 39 Comparative Example 2 48

It can be seen that the composition of the present invention is clearly excellent in PEB time dependence.

According to the present invention, it is possible to provide a resist composition which is not affected by the post-exposure heat treatment time variation.

Claims (13)

All repeating units are acrylic units, have an alicyclic group, have no aromatic group, contain resin (A) which improves the solubility in a developing solution by the action of an acid, and contain acrylic and methacrylic units as repeating units. A positive resist composition comprising a resin (B) which does not have, and which has a solubility in a developing solution due to the action of an acid, and a compound (C) which generates an acid by irradiation with actinic light or radiation. The positive resist composition according to claim 1, wherein the proportion of the acrylic units of the resin (B) is 20 to 80 mol% of all the repeating units. The positive resist composition according to claim 1 or 2, wherein the glass transition temperatures of the resin (A) and the resin (B) are all 120 ° C or higher. The positive resist composition according to claim 1 or 2, wherein the difference between the glass transition temperatures of the resin (A) and the resin (B) is less than 5 ° C. The positive resist composition according to claim 1 or 2, wherein at least one of the resin (A) and the resin (B) contains a repeating unit having a structure represented by the following general formula.

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z is an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates. R ₁₂ to R ₁₄ each independently represent an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ represents an alicyclic hydrocarbon group) The positive resist composition according to claim 3, wherein the difference between the glass transition temperatures of the resin (A) and the resin (B) is less than 5 ° C. The positive resist composition according to claim 3, wherein at least one of the resin (A) and the resin (B) contains a repeating unit having a structure represented by the following general formula.

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z is an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates. R ₁₂ to R ₁₄ each independently represent an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ represents an alicyclic hydrocarbon group) The positive resist composition according to claim 4, wherein at least one of the resin (A) and the resin (B) contains a repeating unit having a structure represented by the following general formula.

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z is an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates. R ₁₂ to R ₁₄ each independently represent an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ represents an alicyclic hydrocarbon group) The positive resist composition according to claim 6, wherein at least one of the resin (A) and the resin (B) contains a repeating unit having a structure represented by the following general formula.

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z is an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates. R ₁₂ to R ₁₄ each independently represent an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ represents an alicyclic hydrocarbon group) The resist pattern is formed by using the positive resist composition of Claim 1 or 2, apply | coating on a board | substrate by a suitable coating method, forming a resist film, exposing through a mask, baking, and developing. Way. The method of claim 10, wherein an anti-reflection film is formed on the substrate. The method of claim 10, wherein the exposure light has a wavelength of 150 nm to 250 nm. After coating and drying the antireflection film on the wafer, the positive resist composition according to claim 1 or 2 is applied thereon and dried to form a positive resist film, which is then formed into a contact pitch of 1/2 pitch with an ArF excimer laser. After exposure, heat processing, developing, and rinsing are included.