JP5215228B2 - Method for producing resin composition for photoresist - Google Patents

Description

The present invention relates to a method for producing a resin composition for a photoresist used when performing fine processing of a semiconductor.

The already proposed ArF excimer laser compatible photoresist resin requires a unit that becomes alkali-soluble by the action of an acid and a unit that provides adhesion to a silicon wafer. In addition, a unit containing an alicyclic skeleton having a polar substituent is also useful for improving dry etching resistance and the like (Patent Documents 1, 2, etc.). In order to obtain high lithography performance, it is considered better to have more units that become alkali-soluble due to the action of acid among the units constituting the photoresist resin (copolymer). The ratio of the unit that provides the adhesion of the unit and the unit that includes the alicyclic skeleton having a polar substituent is relatively small, and the necessary functions are reduced. As a result, a fine pattern can be stably and accurately obtained. It becomes difficult to form.

JP 2000-26446 A JP-A-9-73137

Accordingly, it is an object of the present invention to provide a method for producing a photoresist resin composition having an improved alkali-soluble function without impairing substrate adhesion and dry etching resistance.

As a result of intensive studies to achieve the above object, the present inventors have found that a polymer having a repeating unit that becomes alkali-soluble by the action of an acid and a repeating unit having a polar group and an alicyclic skeleton, and an alicyclic When used in a specific ratio in combination with a polymer mainly composed of a repeating unit that has a skeleton and is alkali-soluble by the action of an acid, the alkali-soluble function is enhanced without impairing substrate adhesion and dry etching resistance. Thus, the present inventors have found that the lithography performance can be remarkably improved and the present invention has been completed.

That is, the present invention
In a mixed solution containing a polymer X having a repeating unit B which contains 1 mol% or more and less than 61 mol% of a repeating unit A1 which becomes alkali-soluble by the action of an acid and has a polar group and an alicyclic skeleton, the monomer mixture M ^Y containing monomer corresponding to the repeating unit A2 which becomes alkali-soluble by the action of and acid has a backbone 61 mol% or more, the polymer X / monomer mixture M ^{Y (weight} ratio ) = 75/25 to 99/1, and a method for producing a resin composition for photoresist, which includes a step of polymerizing by adding an amount such that
It contains 1 mol% or more and less than 61 mol% of at least one repeating unit A1 selected from the following formulas (Ia) to (Ic) that becomes alkali-soluble by the action of an acid, and has a polar group and an alicyclic skeleton. At least one selected from the following formulas (Ia) to (Ic) having an alicyclic skeleton and alkali-soluble by the action of an acid in a mixed solution containing the polymer X having the repeating unit B an amount such that the monomer mixture ^{M Y} containing a monomer corresponding to the repeating unit A2 80 mol% or more, the polymer X / monomer mixture ^{M Y} (weight ratio) = 75/25 to 99/1 A process for producing a resin composition for photoresist, which comprises a step of polymerizing by adding only

(In the formula, ring Z represents an optionally substituted alicyclic hydrocarbon ring having 6 to 20 carbon atoms. R represents a hydrogen atom or a methyl group. R ^{1 to} R ³ are the same or Differently, it represents an alkyl group having 1 to 6 carbon atoms, and R ⁴ is a substituent bonded to ring Z and may be the same or different and may be protected with an oxo group, an alkyl group or a protecting group. A hydroxyl group, a hydroxyalkyl group that may be protected with a protecting group, or a carboxyl group that may be protected with a protecting group, provided that at least one of n R ⁴ represents a —COOR ^a group. R ^a represents ^a tertiary hydrocarbon group, a tetrahydrofuranyl group, a tetrahydropyranyl group, or an oxepanyl group which may have ^a substituent, and n represents an integer of 1 to 3).
In the mixed solution containing the polymer Y having 61 mol% or more of the repeating unit A2 having an alicyclic skeleton and becoming alkali-soluble by the action of an acid, the repeating unit unit A1 becoming alkali-soluble by the action of an acid. A monomer mixture M ^X containing a monomer corresponding to the repeating unit B containing 1 mol% or more and less than 61 mol% of a corresponding monomer and having a polar group and an alicyclic skeleton is converted into a monomer mixture M ^X / Polymer Y (weight ratio) = 75/25 to 99/1, and a method for producing a resin composition for photoresist comprising a step of polymerizing, and an alicyclic skeleton and an acid Alkaline can be made alkaline by the action of an acid in a mixed solution containing a polymer Y containing 80 mol% or more of at least one repeating unit A2 selected from the following formulas (Ia) to (Ic), which becomes alkali-soluble by the action. The following formula (I ) To (Ic), the monomer corresponding to at least one repeating unit A1 selected from the group consisting of 1 mol% to less than 61 mol% and having a polar group and an alicyclic skeleton. For a photoresist including a step of polymerizing a monomer mixture M ^X containing a monomer in an amount such that the monomer mixture M ^X / polymer Y (weight ratio) = 75/25 to 99/1 It is a manufacturing method of a resin composition.

(In the formula, ring Z represents an optionally substituted alicyclic hydrocarbon ring having 6 to 20 carbon atoms. R represents a hydrogen atom or a methyl group. R ^{1 to} R ³ are the same or Differently, it represents an alkyl group having 1 to 6 carbon atoms, and R ⁴ is a substituent bonded to ring Z and may be the same or different and may be protected with an oxo group, an alkyl group or a protecting group. A hydroxyl group, a hydroxyalkyl group that may be protected with a protecting group, or a carboxyl group that may be protected with a protecting group, provided that at least one of n R ⁴ represents a —COOR ^a group. R ^a represents ^a tertiary hydrocarbon group, a tetrahydrofuranyl group, a tetrahydropyranyl group, or an oxepanyl group which may have ^a substituent, and n represents an integer of 1 to 3).

In the present specification, “acryl” and “methacryl” may be collectively referred to as “(meth) acryl”, “acryloyl” and “methacryloyl” may be collectively referred to as “(meth) acryloyl”, and the like. In addition, as a protecting group such as a hydroxyl group and a carboxyl group, those commonly used in the field of organic synthesis can be used.

According to the present invention, a polymer having a repeating unit that becomes alkali-soluble by the action of an acid, a repeating unit having a polar group and an alicyclic skeleton, and an alkali capable by the action of an acid. Since a polymer mainly composed of a repeating unit to be dissolved is used in combination at a specific ratio, the developer may easily penetrate into the coating film at the exposed site due to the presence of the latter polymer during development. The alkali-soluble function can be enhanced without impairing adhesion and dry etching resistance, and the lithography performance can be greatly improved. Therefore, a fine pattern can be formed with high accuracy by using such a resin composition for a photoresist for manufacturing a semiconductor.

In the present invention, the polymer X has a repeating unit B that contains 1 mol% or more and less than 61 mol% of the repeating unit A1 that becomes alkali-soluble by the action of an acid and has a polar group and an alicyclic skeleton.

As the repeating unit A1 which becomes alkali-soluble by the action of an acid, those which are eliminated by an acid generated from a photoacid generator upon exposure and are soluble in an alkali developer (a repeating unit having an acid-eliminable group) If it is, it will not specifically limit, For example, the repetition corresponding to the (meth) acrylic acid ester which has a C6-C20 alicyclic hydrocarbon group and has group which can detach | desorb by the effect | action of an acid Unit (repeating unit when polymerized at a carbon-carbon double bond site) and the like. “A (meth) acrylic acid ester containing a alicyclic hydrocarbon group having 6 to 20 carbon atoms and having a group removable by the action of an acid” includes an alicyclic group having 6 to 20 carbon atoms. A (meth) acrylic acid ester having a hydrocarbon group and a tertiary carbon atom at the bonding site with an oxygen atom constituting the ester bond of the (meth) acrylic acid ester is included. The alicyclic hydrocarbon group may be directly bonded to an oxygen atom constituting the ester bond of (meth) acrylic acid ester, or may be bonded via a linking group such as an alkylene group. The alicyclic hydrocarbon group having 6 to 20 carbon atoms may be a monocyclic hydrocarbon group or a polycyclic (bridged cyclic) hydrocarbon group. As a typical example of a unit corresponding to such a (meth) acrylic acid ester, units represented by the formulas (Ia) and (Ib) are exemplified.

In addition, “(meth) acrylic acid ester having a group having 6 to 20 carbon atoms and having a group capable of leaving by the action of an acid” includes an aliphatic group having 6 to 20 carbon atoms. A cyclic hydrocarbon group and a -COOR ^a group (R ^a is an optionally substituted tertiary hydrocarbon group, tetrahydrofuranyl group, tetrahydropyranyl group, Or a (meth) acrylic acid ester to which an oxepanyl group is bonded directly or via a linking group. Examples of the tertiary hydrocarbon group in R ^a of the —COOR ^a group include t-butyl, t-amyl, 2-methyl-2-adamantyl, (1-methyl-1-adamantyl) ethyl group, and the like. . Examples of the substituent that this tertiary hydrocarbon group may have include, for example, a halogen atom, an alkyl group (eg, a C _1-4 alkyl group), a hydroxyl group optionally protected by a protecting group, oxo And a carboxyl group which may be protected with a protecting group. In addition, the tetrahydrofuranyl group in ^Ra includes a 2-tetrahydrofuranyl group, the tetrahydropyranyl group includes a 2-tetrahydropyranyl group, and the oxepanyl group includes a 2-oxepanyl group. Examples of the linking group include an alkylene group (for example, a linear or branched alkyl group having 1 to 6 carbon atoms). The alicyclic hydrocarbon group may be directly bonded to an oxygen atom constituting the ester bond of (meth) acrylic acid ester, or may be bonded via a linking group such as an alkylene group. The alicyclic hydrocarbon group having 6 to 20 carbon atoms may be a monocyclic hydrocarbon group or a polycyclic (bridged cyclic) hydrocarbon group. As a typical example of a unit corresponding to such a (meth) acrylic acid ester, a unit represented by the formula (Ic) is exemplified.

Further, as a repeating unit A1 that becomes alkali-soluble by the action of an acid, a lactone ring in which an oxygen atom constituting an ester bond is bonded to the β-position of the lactone ring and has at least one hydrogen atom in the α-position of the lactone ring. It is also possible to use a repeating unit (a repeating unit when polymerized at a carbon-carbon double bond site) corresponding to the (meth) acrylic acid ester contained. The repeating unit A1 may be only one type or a combination of two or more types.

The repeating unit A1 is preferably at least one repeating unit selected from the formulas (Ia) to (Ic). In formulas (Ia) to (Ic), the alicyclic hydrocarbon ring having 6 to 20 carbon atoms in ring Z may be a single ring or a polycyclic ring such as a condensed ring or a bridged ring. Typical alicyclic hydrocarbon rings include, for example, cyclohexane ring, cyclooctane ring, cyclodecane ring, adamantane ring, norbornane ring, norbornene ring, bornane ring, isobornane ring, perhydroindene ring, decalin ring, perhydrofluorene ring. (Tricyclo [7.4.0.0 ^3,8 ] tridecane ring), perhydroanthracene ring, tricyclo [5.2.1.0 ^2,6 ] decane ring, tricyclo [4.2.2.1 ^{2, 5} ] undecane ring, tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodecane ring and the like. The alicyclic hydrocarbon ring includes an alkyl group such as a methyl group (for example, a C _1-4 alkyl group), a halogen atom such as a chlorine atom, a hydroxyl group optionally protected by a protecting group, an oxo group, a protected group It may have a substituent such as a carboxyl group which may be protected with a group. Ring Z is preferably a polycyclic alicyclic hydrocarbon ring (bridged hydrocarbon ring).

In formulas (Ia) and (Ib), examples of the alkyl group having 1 to 6 carbon atoms in R ^{1 to} R ³ include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, and hexyl. And a linear or branched alkyl group having 1 to 6 carbon atoms such as a group. In the formula (Ic), examples of the alkyl group for R ⁴ include a straight chain such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, hexyl, octyl, decyl, and dodecyl groups. Examples include branched chain alkyl groups having about 1 to 20 carbon atoms. Examples of the hydroxyl group that may be protected with a protecting group for R ⁴ include a hydroxyl group and a substituted oxy group (for example, a C _1-4 alkoxy group such as a methoxy, ethoxy, and propoxy group). Examples of the hydroxyalkyl group which may be protected with a protecting group include a group in which a hydroxyl group which may be protected with the protecting group is bonded via an alkylene group having 1 to 6 carbon atoms. Examples of the carboxyl group that may be protected with a protecting group include -COOR ^b group. R ^b represents a hydrogen atom or an alkyl group, and examples of the alkyl group include linear or branched carbon such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, and hexyl groups. Examples thereof include alkyl groups of 1 to 6. In ^{R 4,} R ^a of -COOR ^a group is the same as above.

As the repeating unit B having the polar group and the alicyclic skeleton, for example, an alicyclic hydrocarbon group having 6 to 20 carbon atoms containing a lactone ring [a lactone ring and a monocyclic or polycyclic (bridged ring)]. A group having a structure in which an alicyclic carbocycle is condensed, etc.] is a monomer unit corresponding to a (meth) acrylic ester bonded to an oxygen atom constituting an ester bond (polymerized at a carbon-carbon double bond site) In the case of repeating units). As a typical example of such a repeating unit, units represented by the formulas (IIa), (IIb), (IIc), (IId) and (IIe) are exemplified. The repeating unit B provides adhesion to a substrate such as a silicon wafer by a polar group and dry etching resistance by an alicyclic skeleton.

In formulas (IIa) to (IIe), examples of the alkyl group in R ^{5 to} R ³⁰ include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, hexyl, octyl, decyl, dodecyl group, and the like. And a linear or branched alkyl group having 1 to 13 carbon atoms. Among these, a C1-C4 alkyl group is preferable. Examples of the hydroxyl group that may be protected with a protecting group include a hydroxyl group and a substituted oxy group (for example, a C _1-4 alkoxy group such as a methoxy, ethoxy, and propoxy group). Examples of the hydroxyalkyl group which may be protected with a protecting group include a group in which a hydroxyl group which may be protected with the protecting group is bonded via an alkylene group having 1 to 6 carbon atoms. Examples of the carboxyl group that may be protected with a protecting group include -COOR ^b group. R ^b is the same as described above.

The polymer X contains repeating units other than the repeating units A1 and B as long as the properties such as alkali solubility (acid detachability), substrate adhesion, dry etching resistance, and solubility in a resist solvent are not impaired. May be. Such a repeating unit is a unit corresponding to a monomer copolymerizable with the monomer corresponding to the repeating unit A2 and the monomer corresponding to the repeating unit B, and does not impair the resist characteristics. If it is a thing, it will not specifically limit. For example, units corresponding to (meth) acrylic acid or derivatives thereof, maleic acid or derivatives thereof, fumaric acid or derivatives thereof, cyclic olefins, and the like can be given. Examples of the (meth) acrylic acid or a derivative thereof include, for example, an alicyclic hydrocarbon group having 6 to 20 carbon atoms having a polar group such as a hydroxyl group, a carboxyl group, and an oxo group (particularly, a bridged cyclic hydrocarbon group). ) Is bonded to an oxygen atom constituting an ester bond, and (meth) acrylic acid ester having a lactone ring.

The content of the repeating unit A1 in the polymer X is 1 mol% or more and less than 61 mol%, preferably 10 to 59 mol%, more preferably about 20 to 50 mol%. When the content of the repeating unit A1 is less than 1 mol%, the solubility of the resist film during alkali development becomes insufficient, the resolution is lowered, and it becomes difficult to form a fine pattern with high accuracy. In addition, when the content of the repeating unit A1 is 61 mol% or more, the substrate adhesion and the dry etching resistance are lowered, and the problem that the pattern is not peeled off by development is likely to occur.

Content of the said repeating unit B in the polymer X is 20-90 mol% normally, Preferably it is 30-80 mol%, More preferably, it is about 40-70 mol%. When the content of the repeating unit B is less than 20 mol%, the substrate adhesion and the dry etching resistance are liable to decrease, and when it exceeds 90 mol%, the amount of alkali-soluble units introduced is reduced. The solubility of the resist film tends to be insufficient.

The weight average molecular weight (Mw) of the polymer X is, for example, about 1000 to 500000, preferably about 3000 to 50000, and the molecular weight distribution (Mw / Mn) is, for example, about 1.5 to 2.5. In addition, said Mn shows a number average molecular weight, and both Mn and Mw are values of polystyrene conversion.

The polymer X can be obtained by copolymerizing a mixture of monomers corresponding to each repeating unit. For example, each of the repeating units represented by the formulas (Ia) to (Ic) and (IIa) to (IIe) can be formed by polymerizing the corresponding (meth) acrylic acid ester as a comonomer.

[Repeating units represented by formulas (Ia) to (Ic)]
The monomer corresponding to the repeating unit represented by the following formula (Ia) ~ (Ic) and, respectively therewith formula (1a) ~ (1c). In the compounds represented by the formulas (1a) to (1c), stereoisomers may exist, but they can be used alone or as a mixture of two or more.

(In the formula, ring Z represents an optionally substituted alicyclic hydrocarbon ring having 6 to 20 carbon atoms. R represents a hydrogen atom or a methyl group. R ^{1 to} R ³ are the same or Differently, it represents an alkyl group having 1 to 6 carbon atoms, and R ⁴ is a substituent bonded to ring Z and may be the same or different and may be protected with an oxo group, an alkyl group or a protecting group. A hydroxyl group, a hydroxyalkyl group that may be protected with a protecting group, or a carboxyl group that may be protected with a protecting group, provided that at least one of n R ⁴ represents a —COOR ^a group. R ^a represents ^a tertiary hydrocarbon group, a tetrahydrofuranyl group, a tetrahydropyranyl group, or an oxepanyl group which may have ^a substituent, and n represents an integer of 1 to 3).

Although the following compound is mentioned as a typical example of a compound represented by Formula (1a), It is not limited to these.
[1-1] 2- (Meth) acryloyloxy-2-methyladamantane (R = H or CH ₃ , R ¹ = CH ₃ , Z = adamantane ring)
[1-2] 1-hydroxy-2- (meth) acryloyloxy-2-methyladamantane (R = H or CH ₃ , R ¹ = CH ₃ , Z = 1 adamantane ring having a hydroxyl group at the 1-position)
[1-3] 5-Hydroxy-2- (meth) acryloyloxy-2-methyladamantane (R = H or CH ₃ , R ¹ = CH ₃ , Z = 5 adamantane ring having a hydroxyl group at the 5-position)
[1-4] 1,3-dihydroxy-2- (meth) acryloyloxy-2-methyladamantane (R = H or CH ₃ , R ¹ = CH ₃ , Z = 1- and adamantane having hydroxyl groups at the 3-position ring)
[1-5] 1,5-dihydroxy-2- (meth) acryloyloxy-2-methyladamantane (R = H or CH ₃ , R ¹ = CH ₃ , Z = 1 adamantane having hydroxyl groups at the 1-position and 5-position ring)
[1-6] 1,3-dihydroxy-6- (meth) acryloyloxy-6-methyladamantane (R = H or CH ₃ , R ¹ = CH ₃ , Z = 1 adamantane having hydroxyl groups at the 1-position and 3-position ring)
[1-7] 2- (Meth) acryloyloxy-2-ethyladamantane (R = H or CH ₃ , R ¹ = CH ₂ CH ₃ , Z = adamantane ring)
[1-8] 1-hydroxy-2- (meth) acryloyloxy-2-ethyladamantane (R = H or CH ₃ , R ¹ = CH ₂ CH ₃ , an adamantane ring having a hydroxyl group at the 1-position)
[1-9] 5-hydroxy-2- (meth) acryloyloxy-2-ethyladamantane (R = H or CH ₃ , R ¹ = CH ₂ CH ₃ , Z = 5 adamantane ring having a hydroxyl group at the 5-position)
[1-10] 1,3-Dihydroxy-2- (meth) acryloyloxy-2-ethyladamantane (R = H or CH ₃ , R ¹ = CH ₂ CH ₃ , Z = 1 and hydroxyl groups at the 3-position Has an adamantane ring)
[1-11] 1,5-dihydroxy-2- (meth) acryloyloxy-2-ethyladamantane (R = H or CH ₃ , R ¹ = CH ₂ CH ₃ , Z = 1 and hydroxyl groups at the 5 position Has an adamantane ring)
[1-12] 1,3-Dihydroxy-6- (meth) acryloyloxy-6-ethyladamantane (R = H or CH ₃ , R ¹ = CH ₂ CH ₃ , Z = 1 and hydroxyl groups at the 3-position Has an adamantane ring)

The compound represented by the above formula (1a), for example, reacts a corresponding cyclic alcohol with (meth) acrylic acid or a reactive derivative thereof according to a conventional esterification method using an acid catalyst or a transesterification catalyst. Can be obtained.

Although the following compound is mentioned as a typical example of a compound represented by Formula (1b), It is not limited to these.
[1-13] 1- (1- (Meth) acryloyloxy-1-methylethyl) adamantane (R = H or CH ₃ , R ² = R ³ = CH ₃ , Z = adamantane ring)
[1-14] 1-hydroxy-3- (1- (meth) acryloyloxy-1-methylethyl) adamantane (R = H or CH ₃ , R ² = R ³ = CH ₃ , hydroxyl group at Z = 1 position Adamantane ring)
[1-15] 1- (1-ethyl-1- (meth) acryloyloxypropyl) adamantane (R = H or CH ₃ , R ² = R ³ = CH ₂ CH ₃ , Z = adamantane ring)
[1-16] 1-hydroxy-3- (1-ethyl-1- (meth) acryloyloxypropyl) adamantane (R = H or CH ₃ , R ² = R ³ = CH ₂ CH ₃ , Z = 1 position) Adamantane ring having a hydroxyl group)
[1-17] 1- (1- (meth) acryloyloxy-1-methylpropyl) adamantane (R = H or CH ₃ , R ² = CH ₃ , R ³ = CH ₂ CH ₃ , Z = adamantane ring)
[1-18] 1-hydroxy-3- (1- (meth) acryloyloxy-1-methylpropyl) adamantane (R = H or CH ₃ , R ² = CH ₃ , R ³ = CH ₂ CH ₃ , Z = Adamantane ring having a hydroxyl group at the 1-position)
[1-19] 1- (1- (Meth) acryloyloxy-1,2-dimethylpropyl) adamantane (R = H or CH ₃ , R ² = CH ₃ , R ³ = CH (CH ₃ ) ₂ , Z = Adamantane ring)
[1-20] 1-hydroxy-3- (1- (meth) acryloyloxy-1,2-dimethylpropyl) adamantane (R = H or CH ₃ , R ² = CH ₃ , R ³ = CH (CH ₃ ) ₂ , Z = 1 adamantane ring having a hydroxyl group at position 1)
[1-21] 1,3-dihydroxy-5- (1- (meth) acryloyloxy-1-methylethyl) adamantane (R = H or CH ₃ , R ² = R ³ = CH ₃ , Z = 1 and An adamantane ring having a hydroxyl group at the 3-position)
[1-22] 1- (1-Ethyl-1- (meth) acryloyloxypropyl) -3,5-dihydroxyadamantane (R = H or CH ₃ , R ² = R ³ = CH ₂ CH ₃ , Z = 3 Adamantane ring with hydroxyl groups at the 5 and 5 positions)
[1-23] 1,3-dihydroxy-5- (1- (meth) acryloyloxy-1-methylpropyl) adamantane (R = H or CH ₃ , R ² = CH ₃ , R ³ = CH ₂ CH ₃ , Z = adamantane ring having hydroxyl groups at the 1- and 3-positions)
[1-24] 1,3-dihydroxy-5- (1- (meth) acryloyloxy-1,2-dimethylpropyl) adamantane (R = H or CH ₃ , R ² = CH ₃ , R ³ = CH (CH ₃ ) ₂ , Z = 1 adamantane ring having hydroxyl groups at the 1- and 3-positions)

The compound represented by the above formula (1b) is, for example, a methanol derivative having an alicyclic group at the corresponding 1-position and (meth) acrylic acid or a reactive derivative thereof using an acid catalyst or a transesterification catalyst. It can be obtained by reacting according to a conventional esterification method.

Although the following compound is mentioned as a typical example of a compound represented by Formula (1c), It is not limited to these.
[1-25] 1-t-Butoxycarbonyl-3- (meth) acryloyloxyadamantane (R = H or CH ₃ , R ⁴ = t-butoxycarbonyl group, n = 1, Z = adamantane ring)
[1-26] 1,3-bis (t-butoxycarbonyl) -5- (meth) acryloyloxyadamantane [R = H or CH ₃ , R ⁴ = t-butoxycarbonyl group, n = 2, Z = adamantane ring ]
[1-27] 1-t-butoxycarbonyl-3-hydroxy-5- (meth) acryloyloxyadamantane (R = H or CH ₃ , R ⁴ = OH, t-butoxycarbonyl group, n = 2, Z = adamantane ring)
[1-28] 1- (2-Tetrahydropyranyloxycarbonyl) -3- (meth) acryloyloxyadamantane (R = H or CH ₃ , R ⁴ = 2-tetrahydropyranyloxycarbonyl group, n = 1, Z = Adamantane ring)
[1-29] 1,3-bis (2-tetrahydropyranyloxycarbonyl) -5- (meth) acryloyloxyadamantane (R = H or CH ₃ , R ⁴ = 2-tetrahydropyranyloxycarbonyl group, n = 2, Z = adamantane ring)
[1-30] 1-hydroxy-3- (2-tetrahydropyranyloxycarbonyl) -5- (meth) acryloyloxyadamantane (R = H or CH ₃ , R ⁴ = OH, 2-tetrahydropyranyloxycarbonyl group , N = 2, Z = adamantane ring)

The compound represented by the above formula (1c), for example, reacts a corresponding cyclic alcohol with (meth) acrylic acid or a reactive derivative thereof according to a conventional esterification method using an acid catalyst or a transesterification catalyst. Can be obtained.

[Repeating units represented by formulas (IIa) to (IIe)]
The following formula (IIa) ~ monomer corresponding to the repeating unit represented by (IIe) and, respectively therewith formula (2a) ~ (2e). In the compounds represented by the formulas (2a) to (2e), stereoisomers may exist, but these can be used alone or as a mixture of two or more.

(In the formula, R represents a hydrogen atom or a methyl group. R ^{5 to} R ⁷ are the same or different and are protected by a hydrogen atom, an alkyl group, a hydroxyl group which may be protected by a protecting group, or a protecting group. A hydroxyalkyl group which may be protected, or a carboxyl group which may be protected with a protecting group, and V ^{1 to} V ³ are the same or different and represent —CH ₂ —, —CO— or —COO—. And at least one of V ^{1 to} V ³ is —COO—, R ^{8 to} R ¹² are the same or different and each represents a hydrogen atom, an alkyl group, a hydroxyl group which may be protected with a protecting group, or a protecting group. R ^{13 to} R ²¹ are the same or different and are protected with a hydrogen atom, an alkyl group or a protecting group, and may be a hydroxyalkyl group which may be protected with or a carboxyl group which may be protected with a protecting group. Also There hydroxyl groups, protected or unprotected hydroxyalkyl group with a protective group, the protective .R ²² to R ³⁰ which indicates a protected or unprotected carboxyl group with a group, which may be the same or different, a hydrogen atom, an alkyl group, protected A hydroxyl group that may be protected with a group, a hydroxyalkyl group that may be protected with a protecting group, and a carboxyl group that may be protected with a protecting group)

Although the following compound is mentioned as a typical example of a compound represented by Formula (2a), It is not limited to these.
[2-1] 1- (meth) acryloyloxy-4-oxo-adamantane (R = H or _{^{CH 3, R 5 = R 6}} = R 7 = H, V 1 = -CO-, V 2 = V 3 = - CH ₂ -)
[2-2] 1- (Meth) acryloyloxy-4-oxatricyclo [4.3.1.1 ^3,8 ] undecan-5-one (R = H or CH ³ , R ⁵ = R ⁶ = R ⁷ = H, V ² = —CO—O— (the left side is the carbon atom side to which R ⁶ is bonded), V ¹ = V ³ = —CH ₂ —)
[2-3] 1- (Meth) acryloyloxy-4,7-dioxatricyclo [4.4.1.1 ^3,9 ] dodecane-5,8-dione (R = H or CH ₃ , R ⁵ = R ⁶ = R ⁷ = H, V ¹ = -CO-O- (the carbon atom side to which R ⁵ is bonded on the left side), V ² = -CO-O- (the left side is bonded with R ⁶ ) Carbon atom side), V3 = —CH ₂ —)
[2-4] 1- (Meth) acryloyloxy-4,8-dioxatricyclo [4.4.1.1 ^3,9 ] dodecane-5,7-dione (R = H or CH ₃ , R ^{5 = R 6 = R 7 = H} , V 1 = -O-CO- ( left bonded to the carbon atom side of the ^{R 5), V 2 = -CO} -O- ( on the left are attached to ^{R 6} Carbon atom side), V ³ = -CH _2- )
[2-5] 1- (Meth) acryloyloxy-5,7-dioxatricyclo [4.4.1.1 ^3,9 ] dodecane-4,8-dione (R = H or CH ₃ , R ⁵ = R ⁶ = R ⁷ = H, V ¹ = —CO—O— (the carbon atom side to which R ⁵ is bonded on the left side), V ² = —O—CO— (the carbon to which R 6 is bonded on the left side) Atomic side), V ³ = -CH _2- )

The compound represented by the formula (2a) is obtained by reacting a corresponding cyclic alcohol derivative with (meth) acrylic acid or a reactive derivative thereof according to a conventional esterification method using an acid catalyst or a transesterification catalyst. Can be obtained.

Although the following compound is mentioned as a typical example of a compound represented by Formula (2b), It is not limited to these.
[2-6] 5- (Meth) acryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (= 5- (meth) acryloyloxy-2,6-norbornane (Carbolactone) (R = H or CH ₃ , R ⁸ = R ⁹ = R ¹⁰ = R ¹¹ = R ¹² = H)
[2-7] 5- (Meth) acryloyloxy-5-methyl-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (R = H or CH ₃ , R ⁸ = CH ₃ , R ⁹ = R ¹⁰ = R ¹¹ = R ¹² = H)
[2-8] 5- (Meth) acryloyloxy-1-methyl-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (R = H or CH ₃ , R ⁹ = CH ₃ , R ⁸ = R ¹⁰ = R ¹¹ = R ¹² = H)
[2-9] 5- (Meth) acryloyloxy-9-methyl-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (R = H or CH ₃ , R ¹⁰ = CH ₃ , R ⁸ = R ⁹ = R ¹¹ = R ¹² = H)
[2-10] 5- (Meth) acryloyloxy-9-carboxy-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (R = H or CH ₃ , R ⁸ = R ⁹ = R ¹¹ = R ¹² = H, R ¹⁰ = COOH)
[2-11] 5- (Meth) acryloyloxy-9-methoxycarbonyl-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (R = H or CH ₃ , R ^{8 = R 9 = R 11 = R} 12 = H, R 10 = methoxy group)
[2-12] 5- (Meth) acryloyloxy-9-ethoxycarbonyl-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (R = H or CH ₃ , R ⁸ = R ⁹ = R ¹¹ = R ¹² = H, R ¹⁰ = ethoxycarbonyl group)
[2-13] 5- (Meth) acryloyloxy-9-t-butoxycarbonyl-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (R = H or CH ₃ , R ⁸ = R ⁹ = R ¹¹ = R ¹² = H, R ¹⁰ = t-butoxycarbonyl group)

The compound represented by the formula (2b) reacts a corresponding cyclic alcohol derivative with (meth) acrylic acid or a reactive derivative thereof according to a conventional esterification method using an acid catalyst or a transesterification catalyst. Can be obtained. In addition, the cyclic alcohol derivative used as a raw material in that case is, for example, a corresponding 5-norbornene-2-carboxylic acid derivative or an ester thereof peracid (peracetic acid, m-chloroperbenzoic acid, etc.) or peroxide ( It can be obtained by reaction (epoxidation and cyclization reaction) with hydrogen peroxide, hydrogen peroxide + metal compound such as tungsten oxide or tungstic acid).

Although the following compound is mentioned as a typical example of a compound represented by Formula (2c), It is not limited to these.
[2-14] 8- (Meth) acryloyloxy-4-oxatricyclo [5.2.1.0 ^2,6 ] decan-5-one (R = H or CH ₃ )
[2-15] 9- (Meth) acryloyloxy-4-oxatricyclo [5.2.1.0 ^2,6 ] decan-5-one (R = H or CH ₃ )

The compound represented by the above formula (2c) is obtained by reacting a corresponding cyclic alcohol derivative with (meth) acrylic acid or a reactive derivative thereof according to a conventional esterification method using an acid catalyst or a transesterification catalyst. Can be obtained.

Although the following compound is mentioned as a typical example of a compound represented by Formula (2d), It is not limited to these.
[2-16] 4- (Meth) acryloyloxy-6-oxabicyclo [3.2.1] octane-7-one (R = H or CH ₃ , R ¹³ = R ¹⁴ = R ¹⁵ = R ¹⁶ = R ^{17 = R 18 = R 19 =} R 20 = R 21 = H)
[2-17] 4- (Meth) acryloyloxy-4-methyl-6-oxabicyclo [3.2.1] octane-7-one (R = H or CH ₃ , R ¹⁴ = R ¹⁵ = R ¹⁶ = R ¹⁷ = R ¹⁸ = R ¹⁹ = R ²⁰ = R ²¹ = H, R ¹³ = CH ₃ )
[2-18] 4- (Meth) acryloyloxy-5-methyl-6-oxabicyclo [3.2.1] octane-7-one (R = H or CH ₃ , R ¹³ = R ¹⁵ = R ¹⁶ = R ¹⁷ = R ¹⁸ = R ¹⁹ = R ²⁰ = R ²¹ = H, R ¹⁴ = CH ₃ )
[2-19] 4- (Meth) acryloyloxy-4,5-dimethyl-6-oxabicyclo [3.2.1] octane-7-one (R = H or CH ₃ , R ¹⁵ = R ¹⁶ = R ^{17 = R 18 = R 19 =} R 20 = R 21 = H, R 13 = R 14 = CH 3)

Although the following compound is mentioned as a typical example of a compound represented by Formula (2e), It is not limited to these.
[2-20] 6- (Meth) acryloyloxy-2-oxabicyclo [2.2.2] octane-3-one (R = H or CH ₃ , R ²² = R ²³ = R ²⁴ = R ²⁵ = R ^{26 = R 27 = R 28 =} R 29 = R 30 = H)
[2-21] 6- (meth) acryloyloxy-6-methyl-2- oxabicyclo [2.2.2] octan-3-one (R = H or ^{_{CH 3, R 22 = R 24}} = R 25 = R ²⁶ = R ²⁷ = R ²⁸ = R ²⁹ = R ³⁰ = H, R ²³ = CH ₃ )
[2-22] 6- (meth) acryloyloxy-1-methyl-2-oxabicyclo [2.2.2] octan-3-one (R = H or ^{_{CH 3, R 23 = R 24}} = R 25 = R ²⁶ = R ²⁷ = R ²⁸ = R ²⁹ = R ³⁰ = H, R ²² = CH ₃ )
[2-23] 6- (Meth) acryloyloxy-1,6-dimethyl-2-oxabicyclo [2.2.2] octane-3-one (R = H or CH ₃ , R ²⁴ = R ²⁵ = R ^{26 = R 27 = R 28 =} R 29 = R 30 = H, R 22 = R 23 = CH 3)

The compounds represented by the above formulas (2d) and (2e) are prepared by a conventional esterification method using a corresponding cyclic alcohol derivative and (meth) acrylic acid or a reactive derivative thereof using an acid catalyst or a transesterification catalyst. It can obtain by making it react according to.

In obtaining the polymer X, the polymerization of the monomer mixture can be performed by a conventional method used for producing an acrylic polymer, such as solution polymerization, bulk polymerization, suspension polymerization, bulk-suspension polymerization, and emulsion polymerization. However, solution polymerization is particularly suitable. Furthermore, drop polymerization is preferable among solution polymerization. Specifically, for example, (i) a monomer solution previously dissolved in an organic solvent and a polymerization initiator solution dissolved in an organic solvent are prepared in an organic solvent kept at a constant temperature. A method in which the monomer solution and the polymerization initiator solution are respectively dropped, and (ii) a method in which a mixed solution in which the monomer and the polymerization initiator are dissolved in an organic solvent is dropped into an organic solvent maintained at a constant temperature. (Iii) A monomer solution previously dissolved in an organic solvent and a polymerization initiator solution dissolved in the organic solvent are prepared, and the polymerization initiator solution is dropped into the monomer solution maintained at a constant temperature. It is performed by a method or the like.

As the polymerization solvent, a known solvent can be used. For example, ether (chain ether such as diethyl ether, propylene glycol monomethyl ether, etc., chain ether such as tetrahydrofuran, dioxane, etc.), ester (methyl acetate, ethyl acetate, Glycol ether esters such as butyl acetate, ethyl lactate, propylene glycol monomethyl ether acetate), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), amides (N, N-dimethylacetamide, N, N-dimethylformamide, etc.) ), Sulfoxide (dimethylsulfoxide, etc.), alcohol (methanol, ethanol, propanol, etc.), hydrocarbon (aromatic hydrocarbons such as benzene, toluene, xylene, etc.) Aliphatic hydrocarbons such as hexane, and alicyclic hydrocarbons such as cyclohexane), and mixtures of these solvents. Moreover, a well-known polymerization initiator can be used as a polymerization initiator. The polymerization temperature can be appropriately selected within a range of about 30 to 150 ° C., for example.

The polymer obtained by polymerization can be purified by precipitation or reprecipitation. The precipitation or reprecipitation solvent may be either an organic solvent or water, or a mixed solvent. Examples of the organic solvent used as the precipitation or reprecipitation solvent include hydrocarbons (aliphatic hydrocarbons such as pentane, hexane, heptane, and octane; alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; aromatics such as benzene, toluene, and xylene. Aromatic hydrocarbons), halogenated hydrocarbons (halogenated aliphatic hydrocarbons such as methylene chloride, chloroform and carbon tetrachloride; halogenated aromatic hydrocarbons such as chlorobenzene and dichlorobenzene), nitro compounds (nitromethane, nitroethane, etc.) , Nitrile (acetonitrile, benzonitrile, etc.), ether (chain ether such as diethyl ether, diisopropyl ether, dimethoxyethane; cyclic ether such as tetrahydrofuran, dioxane), ketone (acetone, methyl ethyl ketone) Diisobutyl ketone, etc.), ester (ethyl acetate, butyl acetate, etc.), carbonate (dimethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, etc.), alcohol (methanol, ethanol, propanol, isopropyl alcohol, butanol, etc.), carboxylic acid (acetic acid, etc.) Etc.), and mixed solvents containing these solvents.

Among these, as the organic solvent used as the precipitation or reprecipitation solvent, a solvent containing at least a hydrocarbon (particularly an aliphatic hydrocarbon such as hexane) is preferable. In such a solvent containing at least hydrocarbon, the ratio of hydrocarbon (for example, aliphatic hydrocarbon such as hexane) and other solvent (for example, esters such as ethyl acetate) is, for example, the former / the latter (volume). Ratio: 25 ° C.) = 10/90 to 99/1, preferably the former / the latter (volume ratio; 25 ° C.) = 30/70 to 98/2, more preferably the former / the latter (volume ratio; 25 ° C.) = 50 / 50 to 97/3.

In the present invention, the polymer Y includes 61 mol% or more (61 to 100 mol%) of a repeating unit A2 having an alicyclic skeleton and alkali-soluble by the action of an acid. As the repeating unit A2 having an alicyclic skeleton and becoming alkali-soluble by the action of an acid, a unit having an alicyclic skeleton among those exemplified as the repeating unit A1 can be used. The repeating unit A1 and the repeating unit A2 may be the same or different. The repeating unit A2 may be only one type or a combination of two or more types. As the alicyclic skeleton, a polycyclic alicyclic skeleton (bridged cyclic skeleton) is particularly preferable.

The repeating unit A2 is preferably at least one repeating unit selected from the formulas (Ia) to (Ic). In addition, the ring Z in the formulas (Ia) to (Ic) is particularly preferably a polycyclic alicyclic hydrocarbon ring (bridged hydrocarbon ring) from the viewpoint of improving dry etching resistance and the like.

The content of the repeating unit A2 in the polymer Y is preferably 70 mol% or more, more preferably 80 mol% or more, and particularly preferably 90 mol% or more. In the polymer Y, the repeating unit other than the repeating unit A2 is a unit corresponding to a monomer copolymerizable with the monomer corresponding to the repeating unit A2, and does not impair the resist characteristics. If there is no particular limitation. For example, in the polymer X, a unit exemplified as a repeating unit other than the repeating unit B and the repeating units A1 and B can be used.

The weight average molecular weight (Mw) of the polymer Y is, for example, about 1000 to 500000, preferably about 3000 to 50000, and the molecular weight distribution (Mw / Mn) is, for example, about 1.5 to 2.5. The polymer Y can be obtained by (co) polymerizing a monomer or monomer mixture corresponding to each repeating unit. For example, each repeating unit represented by the formulas (Ia) to (Ic) can be formed by subjecting the corresponding (meth) acrylic acid ester to polymerization as a comonomer.

As the synthesis method and purification method of the polymer Y, the same methods as in the case of the polymer X can be employed.

The photoresist resin composition of the present invention contains the polymer X and the polymer Y at a ratio of polymer X / polymer Y (weight ratio) = 75/25 to 99/1. When this ratio is less than 75/25, the substrate adhesion and the dry etching resistance are lowered, and the problem that the pattern is not peeled off by development is likely to occur. On the other hand, if this ratio is larger than 99/1, the solubility of the resist film during alkali development becomes insufficient, the resolution is lowered, and it becomes difficult to form a fine pattern with high accuracy. The ratio is preferably 75/25 to 95/5, and more preferably about 80/20 to 93/7.

The resin composition for photoresists of the present invention may contain a polymer other than the polymer X and the polymer Y as long as the resist performance is not impaired. The proportion of the polymer other than the polymer X and the polymer Y is usually 30% by weight or less, preferably 20% by weight or less, more preferably 10% by weight or less of the total polymer.

The photoresist resin composition of the present invention usually contains a photoacid generator. Examples of the photoacid generator include conventional or known compounds that efficiently generate acid upon exposure, such as diazonium salts, iodonium salts (for example, diphenyliodohexafluorophosphate), sulfonium salts (for example, triphenylsulfonium hexafluoroantimony). Nates, triphenylsulfonium hexafluorophosphate, triphenylsulfonium methanesulfonate, etc.), sulfonate esters [eg 1-phenyl-1- (4-methylphenyl) sulfonyloxy-1-benzoylmethane, 1,2,3-tri Sulfonyloxymethylbenzene, 1,3-dinitro-2- (4-phenylsulfonyloxymethyl) benzene, 1-phenyl-1- (4-methylphenylsulfonyloxymethyl) -1-hydroxy-1-benzo Rumetan etc.], oxathiazole derivatives, s- triazine derivatives, disulfone derivatives (diphenyl sulfone) imide compound, an oxime sulfonate, a diazonaphthoquinone, and benzoin tosylate. These photoacid generators can be used alone or in combination of two or more.

The amount of the photoacid generator used can be appropriately selected according to the strength of the acid generated by light irradiation, the ratio of each repeating unit in the polymer, etc., for example, 0.1 to 30 parts by weight with respect to 100 parts by weight of the polymer, Preferably it can be selected from the range of about 1 to 25 parts by weight, more preferably about 2 to 20 parts by weight.

The resin composition for photoresist includes alkali-soluble components such as alkali-soluble resins (for example, novolak resins, phenol resins, imide resins, carboxyl group-containing resins), colorants (for example, dyes), organic solvents (for example, Hydrocarbons, halogenated hydrocarbons, alcohols, esters, amides, ketones, ethers, cellosolves, carbitols, glycol ether esters, mixed solvents thereof, etc.) .

The photoresist resin composition of the present invention can be prepared, for example, by the following method.

The first method for producing a resin composition for photoresists of the present invention is a repeating method comprising a repeating unit A1 that is alkali-soluble by the action of an acid and containing 1 mol% or more and less than 61 mol% and having a polar group and an alicyclic skeleton. A monomer mixture containing 61 mol% or more of a monomer corresponding to the repeating unit A2 having an alicyclic skeleton and alkali-soluble by the action of an acid in a mixed solution containing the polymer X having the unit B the M ^Y, contains a polymer X / monomer mixture ^{M Y} (weight ratio) = 75/25 to 99/1 to become such an amount only addition step of polymerizing.

More specifically, for example, an alicyclic solution is added to an organic solvent solution of the polymer X synthesized by the above method (a reaction solution after polymerization of the polymer X, a solution in which the purified polymer X is dissolved in an organic solvent, etc.). the monomer mixture M ^Y containing monomer corresponding to the repeating unit A2 which becomes alkali-soluble by the action of and acid has the formula backbone 61 mol% or more, the polymer X / monomer mixture M ^{Y (wt} Ratio) = 75/25 to 99/1, added in an amount, and polymerized by the above method (drop polymerization method, etc.) and added with a photoacid generator or the like, or the polymer obtained After purification, a resin composition for a photoresist can be prepared by dissolving in a suitable organic solvent together with a photoacid generator and the like.

In the monomer mixture M ^Y, the content of the monomer corresponding to the repeating unit A2 is preferably 70 mol% or more, more preferably 80 mol% or more, preferably in particular 90 mol% or more is there. The monomer other than the monomer corresponding to the repeating unit A2 is a monomer copolymerizable with the monomer corresponding to the repeating unit A2, and does not impair the resist characteristics. There is no particular limitation. Examples thereof include (meth) acrylic acid or a derivative thereof, maleic acid or a derivative thereof, fumaric acid or a derivative thereof, and cyclic olefins. Examples of (meth) acrylic acid or derivatives thereof include those described above. The ratio of the polymer X and the monomer mixture ^{M Y} is preferably a polymer X / monomer mixture ^{M Y} (weight ratio) = 75/25 to 95/5, more preferably 80 / 20-93 / It is about 7.

The second production method of the resin composition for photoresist of the present invention is a mixture containing a polymer Y having an alicyclic skeleton and containing 61 mol% or more of a repeating unit A2 that becomes alkali-soluble by the action of an acid. Monomer corresponding to repeating unit B containing 1 mol% or more and less than 61 mol% of a monomer corresponding to repeating unit A1 that is alkali-soluble by the action of an acid in the liquid and having a polar group and an alicyclic skeleton Is added to the monomer mixture M ^X containing the monomer mixture M ^X / polymer Y (weight ratio) = 75/25 to 99/1 and polymerized.

More specifically, for example, an organic solvent solution of the polymer Y prepared by the above method (a reaction solution after polymerization of the polymer Y, a solution in which the purified polymer Y is dissolved in an organic solvent, etc.) Monomer containing a monomer corresponding to repeating unit A1 which is 1 mol% or more and less than 61 mol% and becomes polar-soluble by action, and which corresponds to repeating unit B having a polar group and an alicyclic skeleton The mixture M ^X is added in such an amount that the monomer mixture M ^X / polymer Y (weight ratio) = 75/25 to 99/1, and polymerized by the above-described method (such as a dropping polymerization method). A resin composition for a photoresist can be prepared by adding a generator or the like, or by purifying the obtained polymer and dissolving it in a suitable organic solvent together with a photoacid generator and the like.

In the monomer mixture ^{M X,} the content of the monomer corresponding to the repeating units A1 is preferably 10 to 59 mol%, more preferably about 20 to 50 mol%. Moreover, content of the monomer corresponding to the repeating unit B is 20-90 mol% normally, Preferably it is 30-80 mol%, More preferably, it is about 40-70 mol%. The ratio of the monomer mixture ^{M X} and the polymer Y is preferably a monomer mixture ^{M X} / polymer Y (weight ratio) = 75/25 to 95/5, more preferably 80 / 20-93 / It is about 7.

The photoresist resin composition thus obtained is applied onto a substrate or a substrate, dried, and then exposed to light on a coating film (resist film) through a predetermined mask (or further subjected to post-exposure baking. Perform) By forming a latent image pattern and then developing it, a fine pattern can be formed with high accuracy.

Examples of the base material or the substrate include a silicon wafer, metal, plastic, glass, and ceramic. The application of the photoresist resin composition can be performed using a conventional application means such as a spin coater, a dip coater, or a roller coater. The thickness of the coating film is, for example, about 0.1 to 20 μm, preferably about 0.3 to 2 μm.

For exposure, light of various wavelengths such as ultraviolet rays and X-rays can be used. For semiconductor resists, g-rays, i-rays, and excimer lasers (eg, XeCl, KrF, KrCl, ArF, ArCl, etc.) are usually used. Etc. are used. The exposure energy is, for example, about 1 to 1000 mJ / cm ² , preferably about 10 to 500 mJ / cm ² .

An acid is generated from the photoacid generator by light irradiation, and this acid causes, for example, a carboxyl group of a repeating unit that becomes alkali-soluble by the action of the acid of the polymer (a repeating unit having an acid-eliminable group = an alkali-soluble unit). And the like, a protecting group (leaving group) such as succinctly desorbs to generate a carboxyl group and the like that contribute to solubilization. Therefore, a predetermined pattern can be accurately formed by development with water or an alkali developer.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. “Acrylate” after the compound number (monomer number) indicates a compound having an acryloyloxy group out of two compounds corresponding to the compound number described in the specification, and is “methacrylate”. Represents a compound having a methacryloyloxy group among the two compounds. The weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn) were determined in terms of standard polystyrene by GPC measurement using a refractometer (RI) as a detector and tetrahydrofuran (THF) as an eluent. For GPC measurement, a column “KF-806L” (trade name) manufactured by Showa Denko Co., Ltd., connected in series, was used. Column temperature was 40 ° C., RI temperature was 40 ° C., and eluent flow rate was 0.8 ml / min. It went on condition of.

Example 1
70 g of THF (tetrahydrofuran) was placed in a round bottom flask equipped with a reflux tube, a stirrer, and a three-way cock, and 1- (1-methacryloyloxy) was maintained therein while maintaining the temperature of the reaction system at 60 ° C. in a nitrogen atmosphere. -1-methylethyl) adamantane [Compound No. [1-13] (methacrylate)] 4.00 g (15.2 mmol), 5-methacryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] Nonan-2-one (= 5-methacryloyloxy-2,6-norbornanecarbolactone) [Compound No. [2-6] (methacrylate)] 0.37 g (1.66 mmol), initiator (Wako Pure Chemical Industries, Ltd.) “V-601”; 0.23 g of dimethyl-2,2′-azobisisobutyrate) and 18 g of THF were added dropwise over 1 hour. It was aged in 5 hours.
Subsequently, 1- (1-methacryloyloxy-1-methylethyl) adamantane [compound number [1-13] (methacrylate)] 20 was maintained in the reaction solution while maintaining the temperature of the reaction system at 60 ° C. in a nitrogen atmosphere. .3 g (77.4 mmol), 5-methacryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (= 5-methacryloyloxy-2,6-norbornanecarbolactone ) [Compound No. [2-6] (methacrylate)] 17.2 g (77.4 mmol), initiator (“V-601” manufactured by Wako Pure Chemical Industries, Ltd .; dimethyl-2,2′-azobisisobutyrate) A mixed solution of 1.90 g and 150 g of THF was added dropwise over 1 hour, and further aged at 60 ° C. for 5 hours. Then, it cooled to room temperature.
After adding 160 g of ethyl acetate to the reaction solution (polymerization solution), this solution is dropped into 1900 g of hexane, the resulting precipitate is filtered off, rinsed twice with 200 g of hexane, and dried under reduced pressure to obtain the desired resin. 34.7 g was obtained. When the collected polymer was analyzed by GPC, the weight average molecular weight (Mw) was 9000 and the molecular weight distribution (Mw / Mn) was 1.9.

Example 2
70 g of THF (tetrahydrofuran) was placed in a round bottom flask equipped with a reflux tube, a stirrer, and a three-way cock, and 2-methacryloyloxy-2--2-siloxane was maintained therein while maintaining the temperature of the reaction system at 60 ° C. in a nitrogen atmosphere. 3.16 g (13.5 mmol) of methyladamantane [compound number [1-1] (methacrylate)], 5-methacryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] nonane-2- ON (= 5-methacryloyloxy-2,6-norbornanecarbolactone) [Compound No. [2-6] (methacrylate)] 0.74 g (3.32 mmol), initiator (“V-601 manufactured by Wako Pure Chemical Industries, Ltd.) ”0.23 g of dimethyl-2,2′-azobisisobutyrate) and 18 g of THF was added dropwise over 1 hour, followed by further aging at 60 ° C. for 5 hours. .
Subsequently, 18.1 g (77. 2-methacryloyloxy-2-methyladamantane [compound number [1-1] (methacrylate)] was maintained in the reaction solution while maintaining the temperature of the reaction system at 60 ° C. in a nitrogen atmosphere. 4 mmol), 5-methacryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (= 5-methacryloyloxy-2,6-norbornanecarbolactone) [compound number [ 2-6] (methacrylate)] 17.2 g (77.4 mmol), initiator (“V-601” manufactured by Wako Pure Chemical Industries, Ltd .; dimethyl-2,2′-azobisisobutyrate) 1.90 g, and A mixed solution of 150 g of THF was added dropwise over 1 hour, and further aged at 60 ° C. for 5 hours. Then, it cooled to room temperature.
After adding 160 g of ethyl acetate to the reaction solution (polymerization solution), this solution is dropped into 1900 g of hexane, the resulting precipitate is filtered off, rinsed twice with 200 g of hexane, and dried under reduced pressure to obtain the desired resin. 33.8 g was obtained. As a result of GPC analysis of the recovered polymer, the weight average molecular weight (Mw) was 8900, and the molecular weight distribution (Mw / Mn) was 1.9.

Example 3
70 g of THF (tetrahydrofuran) was placed in a round bottom flask equipped with a reflux tube, a stirrer, and a three-way cock, and 2-methacryloyloxy-2--2-siloxane was maintained therein while maintaining the temperature of the reaction system at 60 ° C. in a nitrogen atmosphere. 3.16 g (13.5 mmol) of methyladamantane [compound number [1-1] (methacrylate)], 5-methacryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] nonane-2- ON (= 5-methacryloyloxy-2,6-norbornanecarbolactone) [Compound No. [2-6] (methacrylate)] 0.74 g (3.32 mmol), 1-methacryloyloxy-3-hydroxyadamantane 1.00 g (4.23 mmol), initiator (“V-601” manufactured by Wako Pure Chemical Industries, Ltd .; dimethyl-2,2′-azobisisobutyrate) 0 23g, and added dropwise a mixed solution over 1 hour of THF18g, and aged further 5 hours at 60 ° C..
Next, 12.1 g of 2-methacryloyloxy-2-methyladamantane [Compound No. [1-1] (methacrylate)] (51. 51 g) was obtained in this reaction solution while maintaining the temperature of the reaction system at 60 ° C. in a nitrogen atmosphere. 6 mmol), 5-methacryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one (= 5-methacryloyloxy-2,6-norbornanecarbolactone) [compound number [ 2-6] (methacrylate)] 11.5 g (51.6 mmol), 1-methacryloyloxy-3-hydroxyadamantane 12.2 g (51.6 mmol), initiator (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.) Dimethyl-2,2′-azobisisobutyrate) 1.90 g and THF 150 g mixed solution was added dropwise over 1 hour, and further 5 at 60 ° C. Between was aged. Then, it cooled to room temperature.
After adding 160 g of ethyl acetate to the reaction solution (polymerization solution), this solution is dropped into 1900 g of hexane, the resulting precipitate is filtered off, rinsed twice with 200 g of hexane, and dried under reduced pressure to obtain the desired resin. 33.5 g was obtained. When the recovered polymer was analyzed by GPC, the weight average molecular weight (Mw) was 8600, and the molecular weight distribution (Mw / Mn) was 1.8.

Example 4
70 g of THF (tetrahydrofuran) was placed in a round bottom flask equipped with a reflux tube, a stirrer, and a three-way cock, and 2-methacryloyloxy-2--2-siloxane was maintained therein while maintaining the temperature of the reaction system at 60 ° C. in a nitrogen atmosphere. Methyl adamantane [Compound No. [1-1] (methacrylate)] 31.6 g (135 mmol), 5-methacryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one ( = 5-methacryloyloxy-2,6-norbornanecarbolactone) [Compound No. [2-6] (methacrylate)] 7.40 g (33.2 mmol), initiator (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.); A mixed solution of 2.3 g of dimethyl-2,2′-azobisisobutyrate) and 180 g of THF was added dropwise over 1 hour, and further aged at 60 ° C. for 5 hours. Then, it cooled to room temperature. The obtained reaction solution is designated as reaction solution 1.
Separately, 70 g of THF (tetrahydrofuran) was placed in a round bottom flask equipped with a reflux tube, a stirring bar, and a three-way cock, and 2-methacryloyloxy- was added to this while maintaining the temperature of the reaction system at 60 ° C. in a nitrogen atmosphere. 2-Methyladamantane [Compound No. [1-1] (methacrylate)] 18.1 g (77.4 mmol), 5-methacryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] nonane- 2-one (= 5-methacryloyloxy-2,6-norbornanecarbolactone) [Compound No. [2-6] (methacrylate)] 17.2 g (77.4 mmol), initiator (“V” manufactured by Wako Pure Chemical Industries, Ltd.) -601 ”; 1.90 g of dimethyl-2,2′-azobisisobutyrate) and 150 g of THF were added dropwise over 1 hour, and further at 60 ° C. for 5 hours. It was aged. Then, it cooled to room temperature. The obtained reaction solution is designated as reaction solution 2.
29 g of the reaction solution 1 and the whole amount of the reaction solution 2 were mixed, and 160 g of ethyl acetate was added to the mixture solution. The obtained solution was dropped into 1900 g of hexane, the resulting precipitate was filtered off, rinsed twice with 200 g of hexane, and dried under reduced pressure to obtain 33.8 g of the desired resin. As a result of GPC analysis of the recovered polymer, the weight average molecular weight (Mw) was 8900, and the molecular weight distribution (Mw / Mn) was 1.9.

Comparative Example 1
70 g of THF (tetrahydrofuran) was placed in a round bottom flask equipped with a reflux tube, a stirrer, and a three-way cock, and 1- (1-methacryloyloxy) was maintained therein while maintaining the temperature of the reaction system at 60 ° C. in a nitrogen atmosphere. -1-methylethyl) adamantane [compound number [1-13] (methacrylate)] 20.3 g (77.4 mmol), 5-methacryloyloxy-3-oxatricyclo [4.2.1.0 ^4,8 ] Nonan-2-one (= 5-methacryloyloxy-2,6-norbornanecarbolactone) [Compound No. [2-6] (methacrylate)] 17.2 g (77.4 mmol), initiator (Wako Pure Chemical Industries, Ltd.) “V-601”; 1.90 g of dimethyl-2,2′-azobisisobutyrate) and 150 g of THF were added dropwise over 1 hour. It was aged for 5 hours at ℃. Then, it cooled to room temperature.
After adding 160 g of ethyl acetate to the reaction solution (polymerization solution), this solution is dropped into 1900 g of hexane, the resulting precipitate is filtered off, rinsed twice with 200 g of hexane, and dried under reduced pressure to obtain the desired resin. 32.5 g was obtained. When the collected polymer was analyzed by GPC, the weight average molecular weight (Mw) was 8500, and the molecular weight distribution (Mw / Mn) was 1.9.

Evaluation Test About each polymer obtained in the above Examples and Comparative Examples, 100 parts by weight of polymer, 3 parts by weight of triphenylsulfonium hexafluoroantimonate, and 2 parts by weight of 1,5-diazabicyclo [4.3.0] -5-nonene. A part was mixed with PGMEA (propylene glycol monomethyl ether acetate) to prepare a resin composition for photoresist having a polymer concentration of 15% by weight. The obtained composition was filtered through a 0.1 μm microfilter and applied onto a silicon wafer by a spin coating method to form a photosensitive layer having a thickness of about 0.4 μm. Then, it was exposed with an ArF excimer laser having a wavelength of 193 nm through a mask, then subjected to a heat treatment at a temperature of 120 ° C. for 90 seconds, developed with a 0.3M tetramethylammonium hydroxide aqueous solution, and rinsed with pure water. As a result, a 0.15 μm line-and-space pattern was clearly and accurately obtained when the polymer of the example was used, but the accuracy of the pattern was obtained when the polymer of the comparative example was used. Was bad and lacked clarity.

Claims (2)

From 1 to less than 61 mol% of at least one repeating unit A1 selected from the following formulas (Ia) to (Ic), which becomes alkali-soluble by the action of an acid, and from the following (IIa) to (IIe) In the mixed solution containing the polymer X having 20 to 90 mol% of the selected repeating unit B,
80 mol% or more of a monomer corresponding to at least one repeating unit A2 selected from the following formulas (Ia) to (Ic), which has an alicyclic skeleton and becomes alkali-soluble by the action of an acid the monomer mixture M ^Y, of the polymer X / monomer mixture M ^Y (weight ratio) = 75 / 25-99 / 1 by an amount such that the addition photoresist resin composition comprising a step of polymerizing Manufacturing method.

(Where
Ring Z represents an alicyclic hydrocarbon ring having 6 to 20 carbon atoms which may have a substituent.
R represents a hydrogen atom or a methyl group.
R ^{1 to} R ³ are the same or different and each represents an alkyl group having 1 to 6 carbon atoms.
R ⁴ is a substituent bonded to the ring Z and is the same or different and is an oxo group, an alkyl group, a hydroxyl group which may be protected with a protecting group, or a hydroxyalkyl which may be protected with a protecting group Or a carboxyl group which may be protected with a protecting group.
Provided that at least one of n R ⁴ represents a -COOR ³ group. R ³ represents a tertiary hydrocarbon group, a tetrahydrofuranyl group, a tetrahydropyranyl group, or an oxepanyl group which may have a substituent.
n represents an integer of 1 to 3)

(Where
R represents a hydrogen atom or a methyl group.
R ^{5 to} R ⁷ are the same or different and are protected with a hydrogen atom, an alkyl group, a hydroxyl group that may be protected with a protecting group, a hydroxyalkyl group that may be protected with a protecting group, or a protecting group. A carboxyl group which may be
V ^{1 to} V ³ are the same or different and represent —CH ₂ —, —CO— or —COO—.
However, at least one of V ^{1 to} V ³ is —COO—.
R ^{8 to} R ¹² are the same or different and are protected with a hydrogen atom, an alkyl group, a hydroxyl group that may be protected with a protecting group, a hydroxyalkyl group that may be protected with a protecting group, or a protecting group. May be a good carboxyl group.
R ^{13 to} R ²¹ are the same or different and are protected with a hydrogen atom, an alkyl group, a hydroxyl group that may be protected with a protecting group, a hydroxyalkyl group that may be protected with a protecting group, or a protecting group. May be a good carboxyl group.
R ^{22 to} R ³⁰ are the same or different and are protected with a hydrogen atom, an alkyl group, a hydroxyl group that may be protected with a protecting group, a hydroxyalkyl group that may be protected with a protecting group, or a protecting group. Indicates a good carboxyl group) A polymer Y having at least 80 mol% of at least one repeating unit A2 selected from the following formulas (Ia) to (Ic), which has an alicyclic skeleton and becomes alkali-soluble by the action of an acid In the mixture,
1 mol% or more and less than 61 mol% of a monomer corresponding to at least one repeating unit A1 selected from the following formulas (Ia) to (Ic), which becomes alkali-soluble by the action of an acid, and the following (IIa ) To (IIe) , the monomer mixture M ^X containing 20 to 90 mol% of the monomer corresponding to the repeating unit B is converted into the monomer mixture M ^X / polymer Y (weight ratio) = 75/25. A method for producing a photoresist resin composition comprising a step of polymerizing by adding an amount such that it is -99/1.

(Where
Ring Z represents an alicyclic hydrocarbon ring having 6 to 20 carbon atoms which may have a substituent.
R represents a hydrogen atom or a methyl group.
R ^{1 to} R ³ are the same or different and each represents an alkyl group having 1 to 6 carbon atoms.
R ⁴ is a substituent bonded to the ring Z and is the same or different and is an oxo group, an alkyl group, a hydroxyl group which may be protected with a protecting group, or a hydroxyalkyl which may be protected with a protecting group Or a carboxyl group which may be protected with a protecting group.
Provided that at least one of n R ⁴ represents a -COOR ³ group. R ³ represents a tertiary hydrocarbon group, a tetrahydrofuranyl group, a tetrahydropyranyl group, or an oxepanyl group which may have a substituent.
n represents an integer of 1 to 3)

(Where
R represents a hydrogen atom or a methyl group.
R ^{5 to} R ⁷ are the same or different and are protected with a hydrogen atom, an alkyl group, a hydroxyl group that may be protected with a protecting group, a hydroxyalkyl group that may be protected with a protecting group, or a protecting group. A carboxyl group which may be
V ^{1 to} V ³ are the same or different and represent —CH ₂ —, —CO— or —COO—.
However, at least one of V ^{1 to} V ³ is —COO—.
R ^{8 to} R ¹² are the same or different and are protected with a hydrogen atom, an alkyl group, a hydroxyl group that may be protected with a protecting group, a hydroxyalkyl group that may be protected with a protecting group, or a protecting group. May be a good carboxyl group.
R ^{13 to} R ²¹ are the same or different and are protected with a hydrogen atom, an alkyl group, a hydroxyl group that may be protected with a protecting group, a hydroxyalkyl group that may be protected with a protecting group, or a protecting group. May be a good carboxyl group.
R ^{22 to} R ³⁰ are the same or different and are protected with a hydrogen atom, an alkyl group, a hydroxyl group that may be protected with a protecting group, a hydroxyalkyl group that may be protected with a protecting group, or a protecting group. Indicates a good carboxyl group)