JP2002049155A - Resist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electron beam or X-ray resist composition having high sensitivity and high resolving power, excellent in PCD and capable of giving a pattern profile excellent in rectangularity. SOLUTION: In the positive type electron beam or X-ray resist composition containing (a) a compound which generates an acid when irradiated with electron beams or X-rays and (b) a resin having a group which is decomposed by the action of the acid and increases solubility in an alkali developing solution, the compound (a) contains a specified sulfonic ester and a specified onium sulfonate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron beam or X-ray resist composition, and more particularly to an electron beam or X-ray resist composition having an excellent pattern profile obtained by irradiation with an electron beam and X-ray. Here, PCD (Post Coating D
elay) Stability refers to the stability of a coating film when a resist composition is applied to a silicon wafer and then left under high vacuum in an electron beam irradiation apparatus.

[0002]

2. Description of the Related Art Electron beams and X-ray resists have attracted attention as resists for forming patterns for manufacturing electronic components such as semiconductor elements, magnetic bubble memories, and integrated circuits.

However, in the case of an electron beam resist, incident electrons have electric charges and interact with the nuclei and electrons of the material constituting the resist, so that when an electron beam enters the resist film, scattering always occurs. Therefore, in the irradiated portion, the irradiation area is larger at the bottom than at the surface of the resist film. In the case of a positive resist, there is a problem that a pattern profile called an inverse tapered shape is formed. On the other hand, in the case of a negative resist, there is a problem that a pattern profile called a tapered shape is formed.

[0004] Further, even when irradiation is performed with a narrowed beam diameter in order to resolve a fine pattern, there is a problem that the irradiation area is widened due to the scattering and the resolving power is deteriorated. Also,
Conventional resists have low sensitivity, and slumping has been a problem in the manufacture of integrated circuits. From this viewpoint, resists having higher sensitivity than conventional electron beams and X-rays are required. As described above, even if a conventional KrF excimer laser resist is irradiated with a pattern as it is by an electron beam, satisfactory results such as sensitivity, resolution and pattern profile are hardly obtained. Stability over time under high vacuum in an electron beam irradiation device (PCD)
Is worsened, and the pattern dimension is changed, which is a problem that has not been caused by the conventional ultraviolet resist. In the next generation X-ray resist, the conventional Kr
When an F excimer laser resist was used, there were serious problems in sensitivity and resolution.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electron beam or X-ray having high sensitivity, high resolution, excellent PCD, and capable of providing an excellent rectangular pattern profile.
An object of the present invention is to provide a linear resist composition.

[0006]

According to the present invention, the following electron beam and X-ray resist compositions are provided to achieve the above object of the present invention.

(1) (a) a compound which generates an acid upon irradiation with an electron beam or X-ray; and (b) a positive electrode containing a resin having a group which is decomposed by the action of an acid to increase the solubility in an alkali developing solution. In an electron beam or X-ray resist composition, the compound (a) which generates an acid upon irradiation with an electron beam or X-ray is (a1) at least one sulfonic acid ester of N-hydroxyimide.
A positive electron beam or X-ray resist composition comprising: (a2) at least one onium sulfonate selected from the group consisting of sulfonium sulfonate and iodonium sulfonate.

(2) (c) A low molecular weight dissolution inhibiting compound having a molecular weight of 3,000 or less, which has a group decomposable by an acid and whose dissolution rate in an alkali developing solution is increased by the action of an acid. The positive electron beam and X-ray resist composition according to the above (1), which is characterized in that:

(3) (a) a compound capable of generating an acid upon irradiation with an electron beam or X-ray; (c) a group having a group decomposable by an acid, and the dissolution rate in an alkaline developer is increased by the action of the acid. , Molecular weight 300
0 or less low molecular dissolution inhibiting compound (d) In a positive electron beam or X-ray resist composition containing a resin which is insoluble in water and soluble in an alkali developing solution, the (a) irradiation of the electron beam or X-ray The compound generating an acid contains (a1) at least one sulfonic acid ester of N-hydroxyimide, and (a2) at least one onium sulfonic acid salt selected from the group consisting of sulfonium sulfonate and iodonium sulfonate. A positive electron beam or X-ray resist composition.

(4) (a) a compound which generates an acid upon irradiation with an electron beam or X-ray; (d) a resin which is insoluble in water and soluble in an alkaline developer; (e) crosslinks with the above resin by the action of an acid. A negative-type electron beam or X-ray resist composition containing an agent, wherein (a) the compound that generates an acid upon irradiation with an electron beam or X-ray is (a1) at least one sulfonic acid ester of N-hydroxyimide; And (a2) a negative electron beam or X-ray resist composition comprising at least one onium sulfonate selected from the group consisting of sulfonium sulfonates and iodonium sulfonates.

(5) (a2) The onium sulfonate selected from sulfonium sulfonate and iodonium sulfonate contains at least one compound represented by the following general formulas (I) to (III): The electron beam or X-ray resist composition according to any one of the above (1) to (4).

[0012]

Embedded image

Wherein R _{1 to} R ₃₇ are the same or different,
A hydrogen atom, a linear, represents branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a hydroxyl group, a halogen atom, or an -S-R ₃₈ group. R ₃₈ is
Represents a linear, branched or cyclic alkyl or aryl group. Further, two or more of R _{1 to} R ₁₅ , R _{16 to} R ₂₇ , and R _{28 to} R ₃₇ are combined to form one or two kinds selected from a single bond, carbon, oxygen, sulfur, and nitrogen. A ring including the above may be formed. And X ^- represents straight-chain may have a substituent group, branched, cyclic alkyl sulfonic acid anion, an aryl sulfonate anion may have a substituent, a camphor sulfonate anion.

(6) The electron beam or X-ray resist composition according to the above (5), wherein X ⁻ is an anion having a fluorine atom. (7) The electron beam or X-ray resist composition according to any one of (1) to (3) and (5) to (6), further comprising (J) a cationically polymerizable compound.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the electron beam and X-ray resist composition of the present invention will be described in detail. (A) Compound that generates an acid upon irradiation with an electron beam or X-ray (hereinafter, also referred to as “component (a)”) Component (a) is (a1) at least one sulfonic acid ester of N-hydroxyimide, And (a2) a compound containing at least one onium sulfonate selected from the group consisting of sulfonium sulfonates and iodonium sulfonates.

(A1) Sulfonate of N-hydroxyimide As the sulfonic ester of N-hydroxyimide,
Examples include a compound represented by the following general formula (PAG6).

[0017]

Embedded image

R ²⁰⁶ is a linear group which may have a substituent,
A branched or cyclic alkyl group, an optionally substituted aralkyl group, a substituted or unsubstituted aryl group, and a camphor group. A is a linear or branched alkylene group which may have a substituent, a monocyclic or polycyclic alkylene group which may have a substituent and may contain a hetero atom, Linear or branched alkenylene group, monocyclic or polycyclic alkenylene group which may be substituted and may contain a hetero atom, arylene group which may be substituted, aralkylene group which may be substituted Is shown.

The linear R ^206, branch, methyl group as cyclic alkyl group, an ethyl group, a propyl group, an isopropyl group, n- butyl group, sec- butyl group, t- butyl group, a hexyl group, as octyl And straight-chain or branched alkyl groups having 1 to 20 carbon atoms and cyclic alkyl groups such as a cyclopropyl group, a cyclopentyl group or a cyclohexyl group. Preferred substituents of the alkyl group include an alkoxy group, an acyl group, an acyloxy group, a chlorine atom, a bromine atom, an iodine atom and the like.

The aralkyl group of R ^{206 includes} an aralkyl group having 7 to 12 carbon atoms such as a benzyl group or a phenethyl group. Preferred substituents of the aralkyl group include a lower alkyl group having 1 to 4 carbon atoms, a lower alkoxy group having 1 to 4 carbon atoms, a nitro group, an acetylamino group, a halogen atom, and the like. ^Examples of the aryl group for R ²⁰⁶ include a phenyl group, a naphthyl group, and an anthranyl group.

Examples of the alkylene group represented by A include a linear or branched alkylene group having 1 to 10 carbon atoms or a monocyclic or polycyclic alkylene group which may contain a hetero atom. Examples of the linear or branched alkylene group include a methylene group, an ethylene group, a propylene group, and an octylene group. Preferred substituents on the alkylene group include an alkoxy group, an acyl group, a formyl group, a nitro group, an acylamino group, a sulfonylamino group, a halogen atom, an aryl group, and an alkoxycarbonyl group.

Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, a t-butoxy group,
1 carbon atom such as octyloxy group and dodecyloxy group
And alkoxy groups having a substituent such as 20 to 20 alkoxy groups or ethoxyethoxy groups. Examples of the acyl group include an acetyl group, a propionyl group, and a benzoyl group. Examples of the acylamino group include an acetylamino group, a propionylamino group and a benzoylamino group. Examples of the sulfonylamino group include a methanesulfonylamino group, an ethanesulfonylamino group, and the like.
And substituted or unsubstituted benzenesulfonylamino groups such as .about.4 sulfonylamino groups and p-toluenesulfonylamino groups. Examples of the aryl group include a phenyl group, a tolyl group, and a naphthyl group. Examples of the alkoxycarbonyl group include an alkoxycarbonyl group having 2 to 20 carbon atoms such as a methoxycarbonyl group, an ethoxycarbonyl group, an ethoxyethoxycarbonyl group, an octyloxycarbonyl group, and a dodecyloxycarbonyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of the cyclic alkylene group include a monocyclic cycloalkylene group having 4 to 8 carbon atoms such as a cyclopentylene group and a cyclohexylene group, and 7-oxabicyclo [2,2,
1] A polycyclic cycloalkylene group having 5 to 15 carbon atoms such as a heptylene group. Preferred substituents of the cycloalkylene group include an alkyl group having 1 to 4 carbon atoms, an alkoxy group, an acyl group, a formyl group, a nitro group, an acylamino group, a sulfonylamino group, a halogen atom, an aryl group, and an alkoxycarbonyl group. Can be The alkoxy group, acyl group, nitro group, acylamino group, sulfonylamino group, aryl group, and alkoxycarbonyl group mentioned herein have the same meanings as those described above. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of the arylene group include a phenylene group and a naphthylene group. Preferred substituents of the arylene group include an alkyl group, a cycloalkyl group, an alkoxy group, an acyl group, a formyl group, a nitro group, an acylamino group, a sulfonylamino group, a halogen atom, an aryl group,
An alkoxycarbonyl group. The alkyl group, cycloalkyl group, alkoxy group, acyl group, formyl group, nitro group, acylamino group, sulfonylamino group, aryl group, and alkoxycarbonyl group mentioned above are the same as those described above. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of the alkenylene group include alkenylene groups having 2 to 4 carbon atoms, such as an ethenylene group and a butenylene group. Preferred substituents of the alkenylene group are an alkyl group, a cycloalkyl group, an alkoxy group and an acyl group. Group, formyl group, nitro group, acylamino group, sulfonylamino group, halogen atom, aryl group,
An alkoxycarbonyl group. The alkyl group, cycloalkyl group, alkoxy group, acyl group, formyl group, nitro group, acylamino group, sulfonylamino group, aryl group, and alkoxycarbonyl group mentioned above are the same as those described above. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of the cyclic alkenylene group include a cyclopentenylene group and a cyclohexenylene group having 4 to 8 carbon atoms.
And monocyclic cycloalkenylene groups, 7-oxabicyclo [2,2,1] heptenylene groups, norbornenylene groups, and polycyclic cycloalkenylene groups having 5 to 15 carbon atoms. Examples of the aralkylene group include a tolylene group and a xylylene group, and examples of the substituent include the substituents described for the arylene group.

Specific examples include the following compounds, but are not limited thereto.

[0028]

Embedded image

[0029]

Embedded image

[0030]

Embedded image

(A2) Onium sulfonate selected from the group consisting of sulfonium sulfonate and iodonium sulfonate The component (a2) is a compound which generates an acid upon irradiation with an electron beam or X-ray, and is a sulfonium sulfonate. , An onium sulfonate selected from the group of iodonium sulfonates.

As the component (a2), the following formula (PAG)
3) or a compound represented by (PAG4).
More preferred are the compounds represented by the above general formulas (I) to (III).

The above general formulas (I) to (a2)
In (III), as the linear or branched alkyl group for R _{1 to} R ₃₈ , a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, which may have a substituent, t
Examples thereof include those having 1 to 4 carbon atoms such as -butyl group. The cyclic alkyl group may have a substituent,
Those having 3 to 8 carbon atoms such as cyclopropyl group, cyclopentyl group and cyclohexyl group are exemplified.

The linear or branched alkoxy group represented by R _{1 to} R ₃₇ includes, for example, methoxy, ethoxy, hydroxyethoxy, propoxy, n-butoxy, isobutoxy, sec-butoxy, t- Examples include those having 1 to 4 carbon atoms such as a butoxy group. Examples of the cyclic alkoxy group include a cyclopentyloxy group, for example, a cyclopentyloxy group and a cyclohexyloxy group.

Examples of the halogen atom represented by R _{1 to} R ₃₇ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the aryl group for R ₃₈ include those having 6 to 14 carbon atoms which may have a substituent such as a phenyl group, a tolyl group, a methoxyphenyl group, and a naphthyl group.

As these substituents, an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom,
A chlorine atom, an iodine atom), an aryl group having 6 to 10 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a cyano group, a hydroxy group, a carboxy group, an alkoxycarbonyl group, and a nitro group.

Further, R _{1 to} R ₁₅ , R _{16 to} R ₂₇ , R _{28 to} R
Of _37, two or more of formed by combining a single bond, carbon, oxygen, one selected sulfur, and nitrogen or 2
Examples of the ring containing more than one kind include a furan ring, a dihydrofuran ring, a pyran ring, a trihydropyran ring, a thiophene ring, a pyrrole ring, and the like.

In the general formulas (I) to (III), X ^- is
Straight-chain, branched, cyclic alkyl sulfonate anion which may have a substituent, aryl sulfonate anion which may have a substituent, camphor sulfonate anion,
The above anion having a fluorine atom is preferred.

These substituents are preferably an alkyl group which may be branched or cyclic, an alkoxy group which may be divided or cyclic, an acyl group, an acyloxy group, a sulfonyl group, a sulfonyloxy group, a sulfonyl group. Examples include an amino group, an aryl group, an aralkyl group, an alkoxycarbonyl group, a nitro group, a hydroxyl group, a halogen atom, and a cyano group.

Examples of the anion having a fluorine atom include an alkyl group substituted with at least one fluorine atom and at least one fluorine atom, which may be branched or cyclic, or substituted with at least one fluorine atom. An alkoxy group which may be branched or cyclic, an acyl group substituted with at least one fluorine atom, an acyloxy group substituted with at least one fluorine atom, a sulfonyl substituted with at least one fluorine atom A sulfonyloxy group substituted with at least one fluorine atom, a sulfonylamino group substituted with at least one fluorine atom,
Aryl groups substituted with at least one fluorine atom, at least one
Benzenesulfonic acid, naphthalenesulfonic acid or anthracenesulfonic acid anion having at least one selected from an aralkyl group substituted with at least one fluorine atom and an alkoxycarbonyl group substituted with at least one fluorine atom And the like.

The linear, branched or cyclic alkyl group preferably has 1 to 12 carbon atoms and is substituted with 1 to 25 fluorine atoms. Specifically, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, a 2,2,2-trifluoroethyl group, a heptafluoropropyl group, a heptafluoroisopropyl group, a perfluorobutyl group, a perfluorooctyl group , Perfluorododecyl group, perfluorocyclohexyl group and the like. Among them, a perfluoroalkyl group having 1 to 4 carbon atoms, all of which is substituted by fluorine, is preferable.

The linear, branched or cyclic alkoxy group preferably has 1 to 12 carbon atoms and is substituted with 1 to 25 fluorine atoms. Specifically, a trifluoromethoxy group, a pentafluoroethoxy group,
Examples include a heptafluoroisopropyloxy group, a perfluorobutoxy group, a perfluorooctyloxy group, a perfluorododecyloxy group, a perfluorocyclohexyloxy group, and the like. Among them, a perfluoroalkoxy group having 1 to 4 carbon atoms, all of which is substituted by fluorine, is preferable.

The acyl group has 2 to 12 carbon atoms.
Wherein those substituted with 1 to 23 fluorine atoms are preferred. Specific examples include a trifluoroacetyl group, a fluoroacetyl group, a pentafluoropropionyl group, and a pentafluorobenzoyl group.

The acyloxy group has 2 to 2 carbon atoms.
12 which is substituted with 1 to 23 fluorine atoms is preferred. Specific examples include a trifluoroacetoxy group, a fluoroacetoxy group, a pentafluoropropionyloxy group, and a pentafluorobenzoyloxy group.

The alkyl or arylsulfonyl group preferably has 1 to 12 carbon atoms and contains 1 to 25 fluorine atoms. Specific examples include a trifluoromethanesulfonyl group, a pentafluoroethanesulfonyl group, a perfluorobutanesulfonyl group, a perfluorooctanesulfonyl group, a pentafluorobenzenesulfonyl group, and a 4-trifluoromethylbenzenesulfonyl group.

The alkyl or arylsulfonyloxy group has 1 to 12 carbon atoms and 1 to 25 carbon atoms.
Those containing two fluorine atoms are preferred. Specific examples include a trifluoromethanesulfonyloxy group, a perfluorobutanesulfonyloxy group, and a 4-trifluoromethylbenzenesulfonyloxy group.

The alkyl or arylsulfonylamino group has 1 to 12 carbon atoms and 1 to 25 carbon atoms.
Those containing two fluorine atoms are preferred. Specific examples include a trifluoromethanesulfonylamino group, a perfluorobutanesulfonylamino group, a perfluorooctanesulfonylamino group, and a pentafluorobenzenesulfonylamino group.

The aryl group has 6 to 1 carbon atoms.
4, which is substituted with 1 to 9 fluorine atoms is preferable. Specifically, a pentafluorophenyl group, 4
-Trifluoromethylphenyl, heptafluoronaphthyl, nonafluoroanthranyl, 4-fluorophenyl, 2,4-difluorophenyl, and the like.

The aralkyl group has 7 to 7 carbon atoms.
It is preferably 10 and substituted by 1 to 15 fluorine atoms. Specific examples include a pentafluorophenylmethyl group, a pentafluorophenylethyl group, a perfluorobenzyl group, a perfluorophenethyl group, and the like.

The alkoxycarbonyl group preferably has 2 to 13 carbon atoms and is substituted by 1 to 25 fluorine atoms. Specific examples include a trifluoromethoxycarbonyl group, a pentafluoroethoxycarbonyl group, a pentafluorophenoxycarbonyl group, a perfluorobutoxycarbonyl group, and a perfluorooctyloxycarbonyl group.

The most preferred X ⁻ is a fluorine-substituted benzenesulfonate anion, and among them, a pentafluorobenzenesulfonate anion is particularly preferred.

The benzene sulfonic acid, naphthalene sulfonic acid or anthracene sulfonic acid having a fluorine-containing substituent further includes a linear, branched or cyclic alkoxy group, an acyl group, an acyloxy group, a sulfonyl group,
It may be substituted with a sulfonyloxy group, a sulfonylamino group, an aryl group, an aralkyl group, an alkoxycarbonyl group (the number of carbon atoms is the same as described above), a halogen (excluding fluorine), a hydroxyl group, a nitro group and the like.

Formula (PAG3) or (PAG4) as component (a2) is shown below.

[0054]

Embedded image

Here, the formulas Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group. Preferred substituents include an alkyl group, a haloalkyl group, a cycloalkyl group, an aryl group, an alkoxy group, a nitro group, a carboxyl group, an alkoxycarbonyl group, a hydroxy group, a mercapto group, and a halogen atom. R ²⁰³ ,
R ²⁰⁴ and R ²⁰⁵ each independently represent a substituted or unsubstituted alkyl group or aryl group. Preferably, the carbon number is 6 to
They are a 14 aryl group, an alkyl group having 1 to 8 carbon atoms, and substituted derivatives thereof. Preferred substituents are an alkoxy group having 1 to 8 carbon atoms, an alkyl group having 1 to 8 carbon atoms, a nitro group, a carboxyl group, a hydroxy group and a halogen atom for the aryl group, and a substituent for the alkyl group. It is an alkoxy group having 1 to 8 carbon atoms, a carboxyl group, or an alkoxycarbonyl group.

Z ^- represents a counter anion, for example, optionally substituted alkanesulfonic acid, perfluoroalkanesulfonic acid, optionally substituted benzenesulfonic acid, naphthalenesulfonic acid, anthracenesulfonic acid, camphorsulfonic acid and the like. Examples include, but are not limited to: Preferred are alkanesulfonic acid, perfluoroalkanesulfonic acid, alkyl-substituted benzenesulfonic acid, and pentafluorobenzenesulfonic acid.

Further, two of R ²⁰³ , R ²⁰⁴ and R ²⁰⁵ and Ar ¹ and Ar ² may be bonded through a single bond or a substituent.

Specific examples of formula (PAG3) or (PAG4) include, but are not limited to, the following compounds.

[0059]

Embedded image

[0060]

Embedded image

[0061]

Embedded image

[0062]

Embedded image

[0063]

Embedded image

[0064]

Embedded image

[0065]

Embedded image

[0066]

Embedded image

[0067]

Embedded image

[0068]

Embedded image

Preferred examples of the component (a2) represented by the general formula (I) include the following compounds.

[0070]

Embedded image

[0071]

Embedded image

[0072]

Embedded image

Specific examples of the component (a2) represented by the general formula (II) are shown below.

[0074]

Embedded image

Specific examples of the component (a2) represented by the general formula (III) are shown below.

[0076]

Embedded image

The content ratio of component (a1) to component (a2) ((a1) :( a2)) is usually from 95: 5 to 5:95,
Preferably 90:10 to 10:90, more preferably 8
0:20 to 20:80.

The content of the component (a) is usually from 0.1 to 20% by weight, preferably from 0.5 to 10% by weight, based on the solid content of the whole composition of the electron beam or X-ray resist composition of the present invention.
More preferably, it is 1 to 7% by weight.

The compound (a1) can be synthesized by reacting N-hydroxyimide and the corresponding sulfonic acid chloride in a suitable solvent under basic conditions. The compounds of the general formulas (I) and (II) are prepared by reacting an aryl Grignard reagent such as aryl magnesium bromide with a substituted or unsubstituted phenyl sulfoxide, and converting the resulting triaryl sulfonium halide with a corresponding sulfonic acid and a salt thereof. Exchange, salt-exchange with substituted or unsubstituted phenylsulfoxide and the corresponding aromatic compound using an acid catalyst such as methanesulfonic acid / diphosphorus pentoxide or aluminum chloride, or diaryliodonium salt and diaryl The sulfide can be synthesized by a method such as condensation and salt exchange using a catalyst such as copper acetate.

The compound of the formula (III) can be synthesized by reacting an aromatic compound with periodate. The sulfonic acid or sulfonic acid salt used for the salt exchange is obtained by, for example, a method of hydrolyzing a commercially available sulfonic acid chloride, a method of reacting an aromatic compound with chlorosulfonic acid, or a method of reacting an aromatic compound with sulfamic acid. Can be obtained by

Hereinafter, a method for synthesizing specific compounds of the general formulas (I) to (III) will be described below. (Synthesis of Pentafluorobenzenesulfonic Acid Tetramethylammonium Salt) 25 g of pentafluorobenzenesulfonyl chloride was dissolved in 100 ml of methanol under ice cooling.
To this was slowly added 100 g of a 25% aqueous solution of tetramethylammonium hydroxide. After stirring at room temperature for 3 hours, a solution of pentafluorobenzenesulfonic acid tetramethylammonium salt was obtained. This solution was used for salt exchange with sulfonium salt and iodonium salt.

(Synthesis of triphenylsulfonium pentafluorobenzenesulfonate: synthesis of specific example (I-1)) Diphenylsulfoxide 509 was converted to benzene 800 m
1 and 200 g of aluminum chloride was added thereto and refluxed for 24 hours. The reaction solution was slowly poured into 2 L of water, and 400 ml of concentrated hydrochloric acid was added thereto, followed by heating at 70 ° C. for 10 minutes. This aqueous solution was washed with 500 ml of ethyl acetate,
After filtration, 200 g of ammonium iodide was added to 400 m of water.
The solution dissolved in 1 was added. The precipitated powder was collected by filtration, washed with water, washed with ethyl acetate and dried to obtain 70 g of triphenylsulfonium iodide. 30.5 g of triphenylsulfonium iodide was added to 1000 ml of methanol.
And 19.1 g of silver oxide was added to the solution, followed by stirring at room temperature for 4 hours. The solution was filtered, and an excess amount of the solution of tetramethylammonium pentafluorobenzenesulfonate synthesized above was added thereto. The reaction solution was concentrated, and this was dissolved in 500 ml of dichloromethane.
% Tetramethylammonium hydroxide aqueous solution and water. After drying the organic phase over anhydrous sodium sulfate,
Concentration provided triphenylsulfonium pentafluorobenzenesulfonate.

(Synthesis of Triarylsulfonium Pentafluorobensene Sulfonate: Specific Examples (I-9) and (II)
Synthesis of a mixture with -1) 50 g of triarylsulfonium chloride (a 50% aqueous solution of triphenylsulfonium chloride, manufactured by Fluka) is dissolved in 500 ml of water, and an excess amount of a solution of tetramethylammonium pentafluorobenzenesulfonate is added thereto. And an oily substance precipitated. The supernatant was removed by decantation, and the obtained oily substance was washed with water and dried to obtain triarylsulfonium pentafluorobenzensulfonate (specific examples (I-9) and (II-1)).
) As a main component.

(Synthesis of di (4-t-amylphenyl) iodonium pentafluorobensensulfonate: Synthesis of specific example (III-1)) 60 g of t-amylbenzene, 39.5 g of potassium iodate, 81 g of acetic anhydride, 170 ml of dichloromethane And 66.8 concentrated sulfuric acid under ice-cooling.
g was slowly added dropwise. After stirring for 2 hours under ice cooling, the mixture was stirred at room temperature for 10 hours. To the reaction mixture was added 500 ml of water under ice cooling, and the mixture was extracted with dichloromethane. The organic phase was washed with sodium bicarbonate and water, and concentrated to obtain di (4-t-amylphenyl) iodonium sulfate. This sulfate was added to a solution of an excess amount of tetramethylammonium pentafluorobenzenesulfonate. To this solution was added 500 ml of water, and the mixture was extracted with dichloromethane. The organic phase was washed with a 5% aqueous solution of tetramethylammonium hydroxide and water, and then concentrated to obtain di (4-t-amylphenyl) iodonium pentafluorobenzenesulfonate. Was done. Other compounds can be synthesized using the same method.

Acid generating compounds which can be used in combination other than the components (a1) and (a2) In the present invention, in addition to the components (a1) and (a2),
A compound that decomposes by irradiation with an electron beam or X-ray to generate an acid may be used in combination.

The amount of the photoacid generator that can be used in combination with the component (a) of the present invention is usually from 100/0 to 20/80, preferably from 100/0 to 20/80 in molar ratio (component (a) / other acid generator). 10
0/0 to 40/60, more preferably 100/0 to 50
/ 50.

Examples of such photoacid generators that can be used in combination include photoinitiators for photocationic polymerization, photoinitiators for photoradical polymerization, photodecolorants for dyes, photochromic agents, and microresists. Known compounds that generate an acid upon irradiation with an electron beam or X-ray and mixtures thereof can be appropriately selected and used.

For example, onium salts such as diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts, arsonium salts, etc.
Organic halogen compound, organic metal / organic halide, o
-Photoacid generators having a nitrobenzyl-type protecting group, compounds that generate sulfonic acid upon photolysis, such as iminosulfonate, and disulfone compounds.

Further, a compound in which a group or a compound which generates an acid upon irradiation with these electron beams or X-rays is introduced into a main chain or a side chain of a polymer, for example, US Pat. No. 3,843
No. 9,137, German Patent No. 3914407, JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038
No., JP-A-63-163452, JP-A-62-153853, JP-A
Compounds described in JP-A-63-146029 can be used.

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

Among the compounds which can be used together and decompose by irradiation with an electron beam or X-ray to generate an acid, those which are particularly effectively used will be described below. (1) The following general formula (PAG) substituted with a trihalomethyl group
The oxazole derivative represented by 1) or the general formula (PAG)
An S-triazine derivative represented by 2).

[0092]

Embedded image

In the formula, R ²⁰¹ is a substituted or unsubstituted aryl group or alkenyl group, and R ²⁰² is a substituted or unsubstituted aryl group, alkenyl group, alkyl group, —C (Y) ₃
Show Y represents a chlorine atom or a bromine atom. Specific examples include the following compounds, but the present invention is not limited thereto.

[0094]

Embedded image

[0095]

Embedded image

[0096]

Embedded image

(2) Disulfone derivatives represented by the following general formula (PAG5).

[0098]

Embedded image

In the formula, Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group. Specific examples include the following compounds, but are not limited thereto.

[0100]

Embedded image

(3) A diazodisulfone derivative represented by the following general formula (PAG7).

[0102]

Embedded image

Here, R represents a linear, branched or cyclic alkyl group or an optionally substituted aryl group. Specific examples include the following compounds,
It is not limited to these.

[0104]

Embedded image

(B) a resin having a group which is decomposed by the action of an acid to increase the solubility in an alkali developing solution (hereinafter referred to as a resin)
A resin having a group that is decomposed by an acid used in the positive electron beam or X-ray resist composition of the present invention and increases solubility in an alkaline developer (component (b)) ) Is a resin having an acid-decomposable group in the main chain or side chain of the resin, or in both the main chain and the side chain. Of these,
A resin having a group which can be decomposed by an acid in a side chain is more preferable.

A preferred group capable of being decomposed by an acid is-
COOA ⁰ and —O—B ⁰ groups. Examples of the groups containing these include the groups represented by —R ⁰ —COOA ⁰ and —Ar—O—B ⁰ . Here, A ⁰ is -C (R ⁰¹ )
^{(R 02) (R 03)} , - showing the ^{Si (R 01) (R 02} ) (R 0 3) or ^{-C (R 04) (R 05} ) -O-R 06 group. B ⁰
Shows A ⁰ or -CO-O-A ⁰ group (R ^0, R ⁰¹ ~R
⁰⁶ and Ar are as defined below).

The acid-decomposable group is preferably a silyl ether group, a cumyl ester group, an acetal group, a tetrahydropyranyl ether group, an enol ether group, an enol ester group, a tertiary alkyl ether group, or a tertiary alkyl ester. And tertiary alkyl carbonate groups. More preferred are a tertiary alkyl ester group, a tertiary alkyl carbonate group, a cumyl ester group, an acetal group, and a tetrahydropyranyl ether group.

Next, when the group decomposable by these acids is bonded as a side chain, the base resin has -OH or -COOH, preferably -R ⁰ -COOH or -Ar-OH group in the side chain. It is an alkali-soluble resin. For example, an alkali-soluble resin described below can be used.

The alkali dissolution rate of these alkali-soluble resins was measured with 0.261N tetramethylammonium hydroxide (TMAH) (23 ° C.) to be 170
A / sec or more is preferable. Particularly preferably 330A
/ Sec or more (A is angstroms). From such a viewpoint, a particularly preferred alkali-soluble resin is
o-, m-, p-poly (hydroxystyrene) and copolymers thereof, hydrogenated poly (hydroxystyrene), halogen- or alkyl-substituted poly (hydroxystyrene), part of poly (hydroxystyrene), O-alkyl Or an O-acylated product, a styrene-hydroxystyrene copolymer, an α-methylstyrene-hydroxystyrene copolymer, and a hydrogenated novolak resin.

The component (b) used in the present invention is described in European Patent No. 248553, JP-A-2-25850 and 3-2.
No. 23860, 4-251259, etc., an alkali-soluble resin is reacted with a precursor of an acid-decomposable group, or an alkali-soluble resin monomer to which an acid-decomposable group is bonded is used. It can be obtained by copolymerization with various monomers.

Specific examples of the component (b) used in the present invention are shown below, but it should not be construed that the invention is limited thereto.

Pt-butoxystyrene / p-hydroxystyrene copolymer, p- (t-butoxycarbonyloxy) styrene / p-hydroxystyrene copolymer, p
-(T-butoxycarbonylmethyloxy) styrene /
p-hydroxystyrene copolymer, 4- (t-butoxycarbonylmethyloxy) -3-methylstyrene / 4
Hydroxy-3-methylstyrene copolymer, p- (t-
(Butoxycarbonylmethyloxy) styrene / p-hydroxystyrene (10% hydrogenated) copolymer, m-
(T-butoxycarbonylmethyloxy) styrene / m
-Hydroxystyrene copolymer, o- (t-butoxycarbonylmethyloxy) styrene / o-hydroxystyrene copolymer, p- (cumyloxycarbonylmethyloxy) styrene / p-hydroxystyrene copolymer, cumyl methacrylate / Methyl methacrylate copolymer,
4-t-butoxycarbonylstyrene / dimethyl maleate copolymer, benzyl methacrylate / tetrahydropyranyl methacrylate,

P- (t-butoxycarbonylmethyloxy) styrene / p-hydroxystyrene / styrene copolymer, pt-butoxystyrene / p-hydroxystyrene / fumaronitrile copolymer, t-butoxystyrene / hydroxyethyl methacrylate Copolymer, styrene / N- (4-hydroxyphenyl) maleimide / N-
(4-t-butoxycarbonyloxyphenyl) maleimide copolymer, p-hydroxystyrene / t-butyl methacrylate copolymer, styrene / p-hydroxystyrene / t-butyl methacrylate copolymer p-hydroxystyrene / t-butyl Acrylate copolymer, styrene / p-hydroxystyrene / t-butyl acrylate copolymer p- (t-butoxycarbonylmethyloxy) styrene / p-hydroxystyrene / N-methylmaleimide copolymer, t-butyl methacrylate / 1 -Adamantyl methyl methacrylate copolymer, p-hydroxystyrene / t-butyl acrylate / p-acetoxystyrene copolymer, p-hydroxystyrene / t-butyl acrylate / p- (t-butoxycarbonyloxy) styrene copolymer , P-hydroxystyrene / t-butyl acrylate / p- (t-butoxycarbonylmethyloxy)
Styrene copolymer,

[0114]

Embedded image

[0115]

Embedded image

[0116]

Embedded image

[0117]

Embedded image

[0118]

Embedded image

[0119]

Embedded image

[0120]

Embedded image

[0121]

Embedded image

[0122]

Embedded image

[0123]

Embedded image

[0124]

Embedded image

In the above specific examples, Me is a methyl group, E
t represents an ethyl group, nBu represents an n-butyl group, iso-Bu represents an isobutyl group, and tBu represents a t-butyl group.

When an acetal group is used as the acid-decomposable group, a polyhydroxy compound is added at the synthesis stage to adjust the alkali dissolution rate and improve heat resistance to introduce a cross-linking site connecting the polymer main chain with a polyfunctional acetal group. May be. The amount of the polyhydroxy compound to be added is 0.01 to 5 mol%, more preferably 0.05 to 4 mol%, based on the amount of hydroxyl groups of the resin. Examples of the polyhydroxy compound include those having 2 to 6 phenolic hydroxyl groups or alcoholic hydroxyl groups, preferably 2 to 4 hydroxyl groups, and more preferably 2 to 4 hydroxyl groups.
Or three. Specific examples of the polyhydroxy compound are shown below, but the present invention is not limited thereto.

[0127]

Embedded image

The content of acid-decomposable groups is determined by the number of acid-decomposable groups (B) and the number of alkali-soluble groups not protected by acid-decomposable groups (S) in the resin. B /
It is represented by (B + S). The content is preferably 0.01 to
0.7, more preferably 0.05 to 0.50, and still more preferably 0.05 to 0.40. B / (B + S)>
A value of 0.7 is not preferred because it causes film shrinkage after PEB, poor adhesion to the substrate, and scum. On the other hand, B / (B + S) <
A value of 0.01 is not preferable because standing waves may be remarkably left on the pattern side wall.

The weight average molecular weight (Mw) of the component (b) is
It is preferably in the range of 2,000 to 200,000. If it is less than 2,000, the film thickness is greatly reduced due to the development of the unirradiated portion, and if it exceeds 200,000, the dissolution rate of the alkali-soluble resin itself in alkali becomes slow and the sensitivity is lowered. More preferably, 5,000 to 100,0
00, more preferably from 8,000 to 50,
000. In addition, molecular weight distribution (Mw / Mn)
Is preferably 1.0 to 4.0, more preferably 1.0 to 4.0.
-2.0, particularly preferably 1.0-1.6, and the smaller the degree of dispersion, the better the heat resistance and image forming properties (pattern profile, defocus latitude, etc.).
Here, the weight average molecular weight is defined as a polystyrene equivalent value of gel permeation chromatography.

Further, the component (b) may be used in combination of two or more kinds. The use amount of these components in the present invention is 40 to 99% by weight, preferably 60 to 95% by weight, based on the solid content of the whole composition. Further, in order to adjust the alkali solubility, an alkali-soluble resin having no acid-decomposable group may be mixed.

(C) a compound having a molecular weight of 3000 or less (component (C)) which is decomposed by the action of an acid and increases the solubility in an alkali developing solution

The present invention provides: (A) a compound that generates an acid upon irradiation with an electron beam or X-ray (b) a positive resist composition containing, as an essential component, a resin having a group that is decomposed by the action of an acid and increases the solubility in an alkaline developer (Hereinafter also referred to as “first composition”); (C) a positive resist composition containing a compound having a molecular weight of 3000 or less, which is decomposed by the action of an acid to increase solubility in an alkali developer, and (d) an alkali-soluble resin as an essential component (hereinafter referred to as “second composition”). Object). Hereinafter, when simply referred to as a positive resist composition, the first composition and the second
It contains both of the compositions.

The component (C) is a component contained as an essential component in the second composition, and is a component that is optionally added to the first composition. The component (C) has a group that can be decomposed by an acid and has a solubility in an alkaline developer which is increased by the action of an acid.
0 to 2,000, more preferably 300 to 1,500 low molecular weight compounds. The component (C) functions as a dissolution inhibitor for the alkali developer in the non-irradiated portion. In the following description, “acid-decomposable dissolution inhibiting compound” has the same meaning as component (C).

The preferred component (C), that is, the preferred acid-decomposable dissolution-inhibiting compound has at least two acid-decomposable groups in its structure, and the distance between the acid-decomposable groups is the longest. A compound that has at least 8 bonding atoms in position except for the acid-decomposable group. A more preferred acid-decomposable dissolution-inhibiting compound is (A) an acid-decomposable compound having at least two groups capable of being decomposed by an acid in its structure, and wherein the distance between the acid-decomposable groups is the farthest. At least 10 and preferably at least 11
, More preferably at least 12 compounds,
And (ii) at least three acid-decomposable groups, and the distance between the acid-decomposable groups is at least 9, and preferably at least 10, excluding the acid-decomposable groups at the farthest position. More preferably, it is a compound passing through at least 11. The upper limit of the number of the bonding atoms is preferably 50, and more preferably 30.

When the acid-decomposable dissolution-inhibiting compound has three or more, preferably four or more acid-decomposable groups, and also when it has two acid-decomposable groups, the acid-decomposable groups have a certain degree of mutual resistance. If the distance is not less than the distance, the dissolution inhibiting property with respect to the alkali-soluble resin is significantly improved. The distance between the acid-decomposable groups is represented by the number of via bond atoms excluding the acid-decomposable groups. For example, in the case of the following compounds (1) and (2), the distance between the acid-decomposable groups is four bonding atoms each,
In compound (3), it has 12 bonding atoms.

[0136]

Embedded image

Further, the acid-decomposable dissolution-inhibiting compound may have a plurality of acid-decomposable groups on one benzene ring, but preferably one acid-decomposable group on one benzene ring. It is a compound composed of a skeleton having a group.

A group which can be decomposed by an acid, that is, —COO-A
⁰ and a group containing a —O—B ⁰ group include —R ⁰ —COO—
A ⁰ or a group represented by —Ar—O—B ⁰ is exemplified.
Here, A ⁰ represents -C (R ⁰¹ ) (R ⁰² ) (R ⁰³ ), -Si
^{(R 01) (R 02)} (R 0 3) or -C (R ⁰⁴⁾
It represents a (R ⁰⁵ ) -OR ⁰⁶ group. B ⁰ is A ⁰ or -CO-
It represents an ^OA group. R ⁰¹ , R ⁰² , R ⁰³ , R ⁰⁴ and R
⁰⁵ is the same or different and represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group or an aryl group, and R ⁰⁶ represents an alkyl group or an aryl group. However, at least two of R ^{01 to} R ⁰³ are groups other than hydrogen atoms, and even if two groups of R ^{01 to} R ⁰³ and R ^{04 to} R ⁰⁶ are bonded to form a ring. Good. R ⁰ represents a divalent or higher valent aliphatic or aromatic hydrocarbon group which may have a substituent, and -Ar- represents a divalent or higher valent which may have a monocyclic or polycyclic substituent. Shows an aromatic group.

The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group and a t-butyl group. Preferred are those having 3 to 10 carbon atoms such as cyclopropyl group, cyclobutyl group, cyclohexyl group and adamantyl group, and alkenyl groups having 2 to 2 carbon atoms such as vinyl group, propenyl group, allyl group and butenyl group. Preferably, the aryl group has 6 to 1 carbon atoms such as phenyl, xylyl, toluyl, cumenyl, naphthyl and anthracenyl.
Four are preferred. Further, as a substituent, a hydroxyl group,
Halogen atom (fluorine, chlorine, bromine, iodine), nitro group, cyano group, the above alkyl group, methoxy group, ethoxy group, hydroxyethoxy group, propoxy group, hydroxypropoxy group, n-butoxy group, isobutoxy group, s
an alkoxy group such as an ec-butoxy group and a t-butoxy group,
Methoxycarbonyl group, alkoxycarbonyl group such as ethoxycarbonyl group, benzyl group, aralkyl group such as phenethyl group, cumyl group, aralkyloxy group, formyl group, acetyl group, butyryl group, benzoyl group, cyanyl group, acyl such as valeryl group Group, acyloxy group such as butyryloxy group, the above alkenyl group, vinyloxy group,
Examples thereof include an alkenyloxy group such as a propenyloxy group, an allyloxy group and a butenyloxy group, an aryloxy group such as the above-described aryl group and phenoxy group, and an aryloxycarbonyl group such as a benzoyloxy group.

The acid-decomposable group is preferably a silyl ether group, a cumyl ester group, an acetal group, a tetrahydropyranyl ether group, an enol ether group, an enol ester group, a tertiary alkyl ether group, or a tertiary alkyl ester group. And tertiary alkyl carbonate groups. More preferred are a tertiary alkyl ester group, a tertiary alkyl carbonate group, a cumyl ester group, and a tetrahydropyranyl ether group.

The component (C) is preferably selected from those described in JP-A No. 1-2
89946, JP-A-1-289947, JP-A-2-
2560, JP-A-3-128959, JP-A-3-1
58855, JP-A-3-179353, JP-A-3-179
191351, JP-A-3-200251, JP-A-3-3
JP-A-200252, JP-A-3-200253, JP-A-3-200254, JP-A-3-200255, JP-A-3-259149, JP-A-3-279958, JP-A-3-279959, JP-A-4-200 1650, JP-A-4-1651, JP-A-4-11260, JP-A-4
-12356, JP-A-4-12357, Japanese Patent Application No. 3-
No. 33229, Japanese Patent Application No. 3-230790, Japanese Patent Application No. 3-230
No. 320438, Japanese Patent Application No. 4-25157, Japanese Patent Application No. 4-
No. 52732, No. 4-103215, No. 4-
104542, Japanese Patent Application No. 4-107885, Japanese Patent Application No. 4
No. -107889, groups shown above some or all of the phenolic OH groups of the polyhydroxy compounds described herein, such as Nos. 4-152195, -R ⁰ -COO-
Protected compounds linked by A ⁰ or B ⁰ groups are included.

More preferably, JP-A-1-289946
JP-A-3-128959, JP-A-3-15885
5, JP-A-3-179353, JP-A-3-2002
No. 51, JP-A-3-200252, JP-A-3-200
255, JP-A-3-259149, JP-A-3-27
9958, JP-A-4-1650, JP-A-4-112
No. 60, JP-A-4-12356, JP-A-4-1235
7, Japanese Patent Application No. 4-25157, Japanese Patent Application No. 4-10321
No. 5, Japanese Patent Application No. 4-104542, Japanese Patent Application No. 4-1078
No. 85, Japanese Patent Application Nos. 4-107889 and 4-15219
No. 5 using the polyhydroxy compound described in the specification.

In the present invention, specific examples of the preferable compound skeleton of the component (C) are shown below.

[0144]

Embedded image

[0145]

Embedded image

[0146]

Embedded image

[0147]

Embedded image

[0148]

Embedded image

[0149]

Embedded image

[0150]

Embedded image

[0151]

Embedded image

[0152]

Embedded image

[0153]

Embedded image

[0154]

Embedded image

[0155]

Embedded image

[0156]

Embedded image

R in the compounds (1) to (44) represents a hydrogen atom,

[0158]

Embedded image

Represents the following. However, at least two or three depending on the structure are groups other than hydrogen atoms, and each substituent R
May not be the same group.

In the case of the first composition, the content of the component (C) is as follows:
Based on the solids content of the first composition, preferably from 3 to 45
% By weight, more preferably 5 to 30% by weight, even more preferably 10 to 25% by weight. (C) in the case of the second composition
The contents of the components are the same as in the first composition.

(D) Resin unnecessary in water and soluble in alkaline developer (hereinafter also referred to as “component (d)” or “(d) alkali-soluble resin”) Electron beam and X-ray resist composition of the present invention In things
As the component (d), a resin that is insoluble in water and soluble in an aqueous alkaline solution can be used.

The alkali dissolution rate of the alkali-soluble resin is preferably at least 20 ° / sec as measured at 23 ° C. with 0.261N tetramethylammonium hydroxide (TMAH). It is particularly preferably at least 200 ° / sec (Å is Angstroms).

Examples of the (d) alkali-soluble resin used in the present invention include novolak resin, hydrogenated novolak resin, acetone-pyrogallol resin, o-polyhydroxystyrene, m-polyhydroxystyrene, p-polyhydroxystyrene, hydrogen Polyhydroxystyrene,
Halogen or alkyl-substituted polyhydroxystyrene, hydroxystyrene-N-substituted maleimide copolymer, o / p- and m / p-hydroxystyrene copolymer, part of O- to hydroxyl group of polyhydroxystyrene
Alkyl compounds (for example, 5 to 30 mol% of O-methyl compound, O- (1-methoxy) ethyl compound, O- (1-ethoxy) ethyl compound, O-2-tetrahydropyranyl compound, O- (t- Butoxycarbonyl) methylated product) or O-acylated product (for example, 5 to 30 mol% o-
Acetylated product, O- (t-butoxy) carbonylated product, etc.), styrene-maleic anhydride copolymer, styrene-
Examples thereof include, but are not limited to, hydroxystyrene copolymer, α-methylstyrene-hydroxystyrene copolymer, carboxyl group-containing methacrylic resin and its derivative, and polyvinyl alcohol derivative.

Particularly preferred (d) alkali-soluble resins are novolak resins and o-polyhydroxystyrene, m-
Polyhydroxystyrene, p-polyhydroxystyrene and copolymers thereof, alkyl-substituted polyhydroxystyrene, partially O-alkylated or O-acylated polyhydroxystyrene, styrene-hydroxystyrene copolymer, α-methyl It is a styrene-hydroxystyrene copolymer. The novolak resin is obtained by subjecting a given monomer as a main component to addition condensation with an aldehyde in the presence of an acidic catalyst.

The weight average molecular weight of the alkali-soluble resin is 2,000 or more, preferably 5,000 to 20,000.
0, more preferably 5,000 to 100,000.

Here, the weight-average molecular weight is defined as the value in terms of polystyrene by gel permeation chromatography. These (d) alkali-soluble resins in the present invention may be used in combination of two or more. (D) The amount of the alkali-soluble resin used is determined by electron beam and X
40 to 9 with respect to the solid content of the entire line resist composition
It is 7% by weight, preferably 60-90% by weight.

(E) a crosslinking agent (hereinafter referred to as “component (e)” or “(e) crosslinking agent”) which crosslinks the above resin by the action of an acid;
In the negative electron beam and X-ray resist composition of the present invention,
(D) A crosslinking agent that is crosslinked by an acid is used together with an alkali-soluble resin and an acid generator.

(E) As the crosslinking agent, a phenol derivative can be used. Preferably, it has a molecular weight of 1200 or less, contains 3 to 5 benzene rings in the molecule, further has 2 or more hydroxymethyl groups or alkoxymethyl groups in total, and has at least one of the hydroxymethyl group and the alkoxymethyl group. Phenol derivatives formed by concentrating on a benzene ring or binding by sorting. By using such a phenol derivative, the effects of the present invention can be made more remarkable. The alkoxymethyl group bonded to the benzene ring preferably has 6 or less carbon atoms. Specifically, methoxymethyl, ethoxymethyl, n-propoxymethyl, i-propoxymethyl, n-butoxymethyl, i-butoxymethyl, sec-butoxymethyl and t-butoxymethyl are preferred. Further, an alkoxy-substituted alkoxy group such as a 2-methoxyethoxy group and a 2-methoxy-1-propyl group is also preferable. Among these phenol derivatives, particularly preferred ones are listed below.

[0169]

Embedded image

[0170]

Embedded image

[0171]

Embedded image

[0172]

Embedded image

[0173]

Embedded image

(In the formula, L ^{1 to} L ⁸ may be the same or different and represent a hydroxymethyl group, a methoxymethyl group or an ethoxymethyl group.)

The phenol derivative having a hydroxymethyl group is prepared by reacting a corresponding phenol compound having no hydroxymethyl group (compound in which L ^{1 to} L ⁸ are hydrogen atoms in the above formula) with formaldehyde in the presence of a base catalyst. Obtainable. At this time, the reaction is preferably performed at a reaction temperature of 60 ° C. or lower in order to prevent resinification and gelation. Specifically, it can be synthesized by a method described in JP-A-6-28067, JP-A-7-64285, or the like.

A phenol derivative having an alkoxymethyl group can be obtained by reacting a corresponding phenol derivative having a hydroxymethyl group with an alcohol in the presence of an acid catalyst. At this time, the reaction is preferably performed at a reaction temperature of 100 ° C. or less in order to prevent resinification and gelation. Specifically, it can be synthesized by a method described in European Patent EP632003A1 or the like. A phenol derivative having a hydroxymethyl group or an alkoxymethyl group synthesized as described above is preferable in terms of stability during storage, but a phenol derivative having an alkoxymethyl group is particularly preferable from the viewpoint of stability during storage.
Such a phenol derivative having two or more hydroxymethyl groups or alkoxymethyl groups in total and concentrated or linked to any benzene ring may be used alone. A combination of the above may be used.

In addition to the above phenol derivatives, the following compounds (i) and (ii) can be used as the crosslinking agent (e). (I) Compound having N-hydroxymethyl group, N-alkoxymethyl group, or N-acyloxymethyl group (ii) Epoxy compound

In the present invention, the crosslinking agent includes
Phenol derivatives are preferred. Further, the above crosslinking agent is
A combination of more than one species may be used. When the above-mentioned crosslinking agent is used in combination, the phenol derivative and (i) or (i)
The ratio of the crosslinking agent in i) is from 100/0 to 0/10 in molar ratio.
0, preferably 90/10 to 20/80, and more preferably 90/10 to 50/50.

(I) As a compound having an N-hydroxymethyl group, an N-alkoxymethyl group or an N-acyloxymethyl group, European Patent Publication (hereinafter referred to as “EP
No. 0,133,216, West German Patent Nos. 3,634,671 and 3,711,264, and monomer-oligomer-melamine-formaldehyde condensates and urea. -Formaldehyde condensate,
Benzoguanamine-formaldehyde condensates disclosed in the alkoxy-substituted compounds disclosed in EP-A-0,212,482 and the like.

More preferred examples include, for example, melamine-formaldehyde derivatives having at least two free N-hydroxymethyl groups, N-alkoxymethyl groups or N-acyloxymethyl groups, among which N-alkoxymethyl derivatives Is particularly preferred.

(Ii) Examples of the epoxy compound include monomer, dimer, oligomer, and polymer epoxy compounds containing one or more epoxy groups. For example, a reaction product of bisphenol A with epichlorohydrin, a reaction product of a low molecular weight phenol-formaldehyde resin with epichlorohydrin and the like can be mentioned. Other examples include epoxy resins described and used in U.S. Pat. No. 4,026,705 and British Patent 1,539,192.

(E) The crosslinking agent is used in an amount of 3 to 70% by weight, preferably 5 to 50% by weight, based on the total solid content of the resist composition. If the amount of the cross-linking agent is less than 3% by weight, the residual film ratio decreases, and if it exceeds 70% by weight, the resolving power decreases, and the stability of the resist solution during storage is not preferred.

(F) Organic basic compound (hereinafter also referred to as "component (f)") The preferable organic basic compound (f) which can be used in the present invention is a compound having a more basic property than phenol. . Among them, a nitrogen-containing basic compound is preferable. Preferred chemical environments include the following formulas (A) to (A).
(E) Structure can be mentioned.

[0184]

Embedded image

Further preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms having different chemical environments in one molecule, and particularly preferred is a ring structure containing a substituted or unsubstituted amino group and a nitrogen atom. Or a compound having an alkylamino group.

Preferred examples include substituted or unsubstituted guanidine, substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazol, substituted or unsubstituted indazol, Unsubstituted pyrazole, substituted or unsubstituted pyrazine, substituted or unsubstituted pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted piperazine, substituted or unsubstituted Substituted aminomorpholine, substituted or unsubstituted aminoalkylmorpholine and the like can be mentioned.

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, hydroxyl group. , A cyano group.

As particularly preferred compounds, guanidine,
1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylamino Pyridine, 2- (aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-6-methylpyridine, 3-aminoethyl Pyridine, 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-pyrazoline, N-aminomorpholine, N-
(2-aminoethyl) morpholine, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,5-diazabicyclo [4.3.0] non-5-ene, 2,4,
5-triphenylimidal, N-cyclohexyl-
N'-morpholinoethylthiourea and the like are preferable, and among them, 1,8-diazabicyclo [5.4.0] undec-7-ene and 1,5-diazabicyclo [4.3.
0] nona-5-ene, 2,4,5-triphenylimidal, N-cyclohexyl-N'-morpholinoethylthiourea and the like, but are not limited thereto.

These organic basic compounds can be used alone or in combination of two or more. The amount of the organic basic compound to be used is generally 0.001 to 10% by weight, preferably 0.01 to 5% by weight, based on the solid content of the whole composition in the composition of the present invention. If the amount is less than 0.001% by weight, the effects of the present invention cannot be obtained. On the other hand, if it exceeds 10% by weight, sensitivity tends to decrease and developability of a non-irradiated portion tends to deteriorate.

(G) Fluorine and / or silicon-based surfactant (hereinafter also referred to as “component (g)”. Next, fluorine as component (g) contained in the electron beam and X-ray resist composition of the present invention. The composition of the present invention may contain either or both of a fluorine-based surfactant and a silicon-based surfactant.

As the component (g), for example,
No. 62-36663, JP-A-61-226746, JP-A-61-226745,
JP-A-62-170950, JP-A-63-34540, JP-A-7-23016
No. 5, JP-A-8-62834, JP-A-9-54432, JP-A-9-598
No. 8, U.S. Pat.No. 5,405,720, No. 5360692, No. 5529881,
No. 5296330, No. 5436098, No. 5576143, No. 5294511
And No. 5824451. The following commercially available surfactants can also be used as they are. As commercially available surfactants that can be used, for example, F-top EF301, EF303, (manufactured by Shin-Akita Chemical Co., Ltd.), Florad FC
430, 431 (Sumitomo 3M Limited), Mega Fuck F171,
F173, F176, F189, R08 (manufactured by Dainippon Ink and Chemicals, Inc.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (manufactured by Asahi Glass Co., Ltd.), Troysol S-366 (Troy Chemical Corp.) )) Or a silicon-based surfactant. Also, polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can be used as a silicon-based surfactant.

The amount of the component (g) is usually 0.00001 to 2% by weight, preferably 0.0001 to 1% by weight, based on the solid content of the whole composition in the composition of the present invention. These surfactants can be used alone or in combination of two or more.

(H) Other components used in the present invention The electron beam and X-ray resist composition of the present invention may further contain, if necessary, a dye, a pigment, a plasticizer, a photosensitizer, and a developer. A compound having two or more phenolic OH groups that promote solubility can be contained.

The compound having two or more phenolic OH groups that can be used in the present invention is preferably a phenol compound having a molecular weight of 1,000 or less. Further, it is necessary to have at least two phenolic hydroxyl groups in the molecule. If the number exceeds 10, the effect of improving the development latitude is lost. When the ratio of the phenolic hydroxyl group to the aromatic ring is less than 0.5, the film thickness dependency is large, and the development latitude tends to be narrow. If this ratio exceeds 1.4, the stability of the composition deteriorates, and it becomes difficult to obtain high resolution and good film thickness dependency, which is not preferable.

The preferred addition amount of this phenol compound is 2 to 50% by weight, more preferably 5 to 30% by weight, based on the alkali-soluble resin (d). 50% by weight
If the addition amount exceeds the above range, the development residue becomes worse and a new defect that the pattern is deformed at the time of development occurs, which is not preferable.

Such phenol compounds having a molecular weight of 1,000 or less can be prepared by those skilled in the art by referring to the methods described in, for example, JP-A-4-122938, JP-A-2-28531, US Pat. No. 4,916,210, and EP 219294. It can be easily synthesized at Specific examples of the phenol compound are shown below, but the compounds that can be used in the present invention are not limited to these.

Resorcin, phloroglucin, 2, 3, 4
-Trihydroxybenzophenone, 2,3,4,4'-
Tetrahydroxybenzophenone, 2,3,4,3 ',
4 ', 5'-hexahydroxybenzophenone, acetone-pyrogallol condensation resin, fluoroglucoside,
4,2 ', 4'-biphenyltetrol, 4,4'-thiobis (1,3-dihydroxy) benzene, 2,2',
4,4'-tetrahydroxydiphenyl ether, 2,
2 ', 4,4'-tetrahydroxydiphenylsulfoxide, 2,2', 4,4'-tetrahydroxydiphenylsulfone, tris (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) Cyclohexane, 4,4- (α-methylbenzylidene) bisphenol, α, α ′, α ″ -tris (4-hydroxyphenyl) -1,3,5-triisopropylbenzene,
α, α ', α "-tris (4-hydroxyphenyl)-
1-ethyl-4-isopropylbenzene, 1,2,2-
Tris (hydroxyphenyl) propane, 1,1,2-
Tris (3,5-dimethyl-4-hydroxyphenyl)
Propane, 2,2,5,5-tetrakis (4-hydroxyphenyl) hexane, 1,2-tetrakis (4-hydroxyphenyl) ethane, 1,1,3-tris (hydroxyphenyl) butane, para [α, α , Α ', α'-tetrakis (4-hydroxyphenyl)]-xylene.

The photosensitive composition of the present invention is dissolved in a solvent capable of dissolving each of the above components, and coated on a support. As the solvent used here, ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl ether acetate , Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate,
Ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, tetrahydrofuran, and the like are preferable, and these solvents can be used alone or in combination. it can.

A surfactant other than the fluorine-based and / or silicon-based surfactant which is the component (g) can be used in combination with the solvent. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octyl phenol ether, polyoxyethylene nonyl phenol ether and the like Polyoxyethylene alkyl allyl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate,
Sorbitan fatty acid esters such as sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate,
Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate and polyoxyethylene sorbitan tristearate, and acrylic or methacrylic (co) polymerization Polyflow No. 75, no. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like. The amount of these surfactants is usually 2% by weight or less, preferably 1% by weight or less, based on the solid content of the entire composition in the composition of the present invention. These surfactants may be added alone or in combination of two or more.

Spinning an electron beam and X-ray resist composition of the present invention on a substrate (eg, a silicon / silicon dioxide coating) such as used in the manufacture of precision integrated circuit devices.
After coating by an appropriate coating method such as a coater, direct irradiation or irradiation through a predetermined mask is performed, followed by baking and development, whereby a good resist pattern can be obtained.

As the developer of the photosensitive composition of the present invention,
Sodium hydroxide, potassium hydroxide, sodium carbonate,
Inorganic alkalis such as sodium silicate, sodium metasilicate and aqueous ammonia, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, and triethylamine and methyldiethylamine Use alkaline aqueous solutions such as triamines, alcoholamines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide, and cyclic amines such as pyrrole and pichelidine. be able to. Further, an appropriate amount of an alcohol or a surfactant may be added to the above alkaline aqueous solution.

[0202]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the contents of the present invention are not limited thereto.

(Synthesis Example of Positive Electron Beam and X-Ray Resist Composition of the Present Invention) [Synthesis Example 1: Synthesis of poly (p-hydroxystyrene / styrene) copolymer] Dehydration and distillation purification based on a conventional method. 35.25 p-tert-butoxystyrene monomer
g (0.2 mol) and 5.21 g of styrene monomer
(0.05 mol) was dissolved in 100 ml of tetrahydrofuran. Under a nitrogen stream and stirring, at 80 ° C., 0.033 g of azobisisobutyronitrile (AIBN) was added three times every 2.5 hours, and finally, stirring was continued for another 5 hours to carry out a polymerization reaction. . The reaction solution was hexane 1200
Then, white resin was precipitated. After drying the obtained resin, it was dissolved in 150 ml of tetrahydrofuran.
4N hydrochloric acid was added thereto, and the mixture was hydrolyzed by heating under reflux for 6 hours, and then reprecipitated in 5 L of ultrapure water. The resin was separated by filtration, washed with water and dried. Further, it was dissolved in 200 ml of tetrahydrofuran, and dropped and reprecipitated in 5 L of ultrapure water with vigorous stirring. This reprecipitation operation was repeated three times. The obtained resin was dried in a vacuum dryer at 120 ° C. for 12 hours to obtain a poly (p-hydroxystyrene / styrene) copolymer.

[Synthesis Example 2: Synthesis of Resin Example (b-21)]
32.4 g (0.2 mol) of p-acetoxystyrene and 7.01 g (0.07 mol) of t-butyl methacrylate were dissolved in 120 ml of butyl acetate, and the mixture was dissolved under a nitrogen stream and stirring.
Azobisisobutyronitrile (AIBN) at 80 ° C
0.033 g was added three times every 2.5 hours, and finally, stirring was continued for another 5 hours to carry out a polymerization reaction.
The reaction solution was poured into 1200 ml of hexane to precipitate a white resin. After drying the obtained resin, methanol 200
Dissolved in ml. 7.7 g of sodium hydroxide
An aqueous solution of (0.19 mol) / water (50 ml) was added, and the mixture was heated at reflux for 1 hour to hydrolyze. Thereafter, 200 ml of water was added for dilution, and neutralized with hydrochloric acid to precipitate a white resin. This resin was separated by filtration, washed with water and dried.
Further, it was dissolved in 200 ml of tetrahydrofuran, and dropped and reprecipitated in 5 L of ultrapure water with vigorous stirring. This reprecipitation operation was repeated three times. The obtained resin was dried in a vacuum dryer at 120 ° C. for 12 hours to obtain a poly (p-hydroxystyrene / t-butyl methacrylate) copolymer.

[Synthesis 3: Synthesis of Resin Example (b-3)] Poly (p-hydroxystyrene) (VP-800 manufactured by Nippon Kansaisha Co., Ltd.)
0) 10 g was dissolved in 50 ml of pyridine, and 3.63 g of di-t-butyl dicarbonate was added dropwise thereto with stirring at room temperature. After stirring at room temperature for 3 hours, the mixture was added dropwise to a solution of 1 L of ion-exchanged water / 20 g of concentrated hydrochloric acid. The precipitated powder was filtered, washed with water, and dried to obtain a resin example (b-3).

[Synthesis 4: Synthesis of Resin Example (b-33)] p
-83.1 g (0.5 mol) of cyclohexylphenol
Was dissolved in 300 ml of toluene, then 150 g of 2-chloroethyl vinyl ether, 25 g of sodium hydroxide,
5 g of tetrabutylammonium bromide and 60 g of triethylamine were added and reacted at 120 ° C. for 5 hours. The reaction solution was washed with water, excess chloroethyl vinyl ether and toluene were distilled off, and the obtained oil was purified by distillation under reduced pressure.
4-Cyclohexylphenoxyethyl vinyl ether was obtained. 20 g of poly (p-hydroxystyrene) (VP-8000 manufactured by Nippon Soda Co., Ltd.) and 6.5 g of 4-cyclohexylphenoxyethyl vinyl ether in 80 ml of THF.
, And 0.01 g of p-toluenesulfonic acid was added thereto and reacted at room temperature for 18 hours. The reaction solution was distilled water 5
L was dripped with vigorous stirring, and the precipitated powder was filtered,
After drying, a resin example (b-33) was obtained.

Resin Examples (b-4), (b-28), (b-28)
30) was also synthesized by the same method using the corresponding trunk polymer and vinyl ether.

(Synthesis Example 1 of Dissolution Inhibitor Compound: Synthesis of Compound Example 16) 1- [α-methyl-α- (4′-hydroxyphenyl) ethyl] -4- [α ′, α′-bis ( 4 "
-Hydroxyphenyl) ethyl] benzene 42.4 g
(0.10 mol) in N, N-dimethylacetamide 30
09.5 ml, and potassium carbonate 49.5 g (0.
35 mol), and 84.8 g of cumyl bromoacetate
(0.33 mol) was added. Then, at 120 ° C, 7
Stirred for hours. The reaction mixture was poured into 2 l of ion-exchanged water, neutralized with acetic acid, and extracted with ethyl acetate. Concentrated ethyl acetate extract, purified, (all _{R -CH 2 COOC (CH 3)} 2 C 6 H 5 group) Compound Example 16 was obtained 70 g.

(Synthesis Example 2 of Dissolution Inhibitor Compound: Synthesis of Compound Example 41) 44 g of 1,3,3,5-tetrakis- (4-hydroxyphenyl) pentane was dissolved in 250 ml of N, N-dimethylacetamide. 70.7 g of potassium carbonate and then 90.3 g of t-butyl bromoacetate
And stirred at 120 ° C. for 7 hours. The reaction mixture was poured into 2 l of ion-exchanged water, and the obtained viscous material was washed with water. This and purified by column chromatography Compound Example 41 (all R is _{-CH 2 COOC 4 H 9 (t} )) is 87
g were obtained.

(Synthesis Example 3 of Dissolution Inhibitor Compound: Synthesis of Compound Example 43) α, α, α ′, α ′, α ″, α ″,-hexakis (4-hydroxyphenyl) -1,3,5 20 g of triethylbenzene in 400 ml of diethyl ether
Was dissolved. Under a nitrogen atmosphere, 42.4 g of 3,4-dihydro-2H-pyran and a catalytic amount of hydrochloric acid were added to this solution,
Refluxed for 24 hours. After the completion of the reaction, a small amount of sodium hydroxide was added, followed by filtration. The filtrate was concentrated and purified by column chromatography to obtain 55.3 g of Compound Example 43 (R is all THP groups).

Examples 1-26, Comparative Examples 1-3 The components shown in Tables 1-2 below were replaced with the solvents 8.2 shown in Tables 1-2.
g, and filtered through a 0.1 μm Teflon (registered trademark) filter to prepare a resist solution. With respect to the resin composition thus prepared, the image performance of the resist by electron beam irradiation was evaluated by the following method.

In the (C) dissolution inhibitor in the table, (C-
1) and (C-2) are as follows.

[0213]

Embedded image

[0214]

Embedded image

The other components in the table are as follows.

[0216]

Embedded image

The basic compounds (F) in the table are as follows. (1): 1,5-diazabicyclo [4.3.0] -5-
Nonene (2): 2,4,5-triphenylimidazole (3): tri-n-butylamine (4): N-hydroxyethylpiperidine

(G) Surfactants in the table are as follows. W-1: Megafac F176 (Dainippon Ink Co., Ltd.)
W-2: Megafac R08 (Dai Nippon Ink Co., Ltd.) W-3: Polysiloxane polymer KP-341 (Shin-Etsu Chemical Co., Ltd.) W-4: Troysol S-366 (Troy Chemical Co., Ltd.) )
Made)

The solvents in the table are as follows. PGMEA: propylene glycol monomethyl ether acetate PGME: propylene glycol monomethyl ether (1-methoxy-2-propanol) EL: ethyl lactate EEP: ethyl ethoxypropionate BL: γ-butyrolactone CH: cyclohexanone

The composition, physical properties and the like of the binder resin used are as follows. (B-3): p-humanoxystyrene / pt-butoxycarboxystyrene copolymer (molar ratio: 80/2)
0), weight average molecular weight 13000, molecular weight distribution (Mw /
Mn) 1.4 (b-4): p-hydroxystyrene / p- (1-ethoxyethoxy) styrene copolymer (molar ratio: 70/3)
0), weight average molecular weight 12000, molecular weight distribution (Mw /
Mn) 1.3 (b-21): p-hydroxystyrene / t-butyl methacrylate copolymer (molar ratio: 70/30), weight average molecular weight 16,000, molecular weight distribution (Mw / Mn) 2.0 (b- 22): p-hydroxystyrene / p- (1-t
-Butoxyethoxy) styrene copolymer (molar ratio: 85)
/ 15), weight average molecular weight 12000, molecular weight distribution (M
w / Mn) 1.1 (b-28): p-hydroxystyrene / p- (1-phenethyloxyethoxy) styrene copolymer (molar ratio:
85/15), weight average molecular weight 12000, molecular weight distribution (Mw / Mn) 1.2 (b-30): p-hydroxystyrene / p- (1-phenoxyethoxyethoxy) styrene copolymer (molar ratio: 85 / 15), weight average molecular weight 13000, molecular weight distribution (Mw / Mn) 1.2 (PHS): poly-p-hydroxystyrene (manufactured by Nippon Soda Co., Ltd., trade name VP-15000) (PHS / St: Synthesis Example 1) P-hydroxystyrene / styrene (molar ratio: 80/20), weight average molecular weight 26000, molecular weight distribution (Mw / Mn)
1.9

[0221]

[Table 1]

[0222]

[Table 2]

A. Evaluation of electron beam irradiation (Evaluation method) The photosensitive resin composition was uniformly applied to a hexamethyldisilazane-treated silicon substrate by a spin coater, and heated and dried on a hot plate at 120 ° C. for 60 seconds. A .8 μm resist film was formed. This resist film is applied to an electron beam lithography system (acceleration voltage 50
(KeV, beam diameter 0.20 μm), and immediately after irradiation, heated on a hot plate at 110 ° C. for 90 seconds. The film was further developed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, and dried. The sample on which the line and space pattern was formed was observed with a scanning electron microscope, and the sensitivity, resolution, PCD
Was evaluated.

(Sensitivity Evaluation Method) Sensitivity represents an irradiation amount for reproducing a 0.18 μm line-and-space (1/1) mask pattern. (Resolving power evaluation method) The resolving power indicates a limit resolving power at an irradiation dose for reproducing a 0.18 μm line and space (1/1) mask pattern.

(Evaluation Method of PCD) The resist film obtained by the above method was left in an electron beam lithography apparatus under high vacuum for 120 minutes, and then a resist pattern was formed by the same method. Irradiation dose obtained by the above sensitivity evaluation method (in this case, there is no standing for 120 minutes under high vacuum after resist film formation,
(Immediate irradiation) at the same irradiation dose. The closer the critical resolution is to the critical resolution obtained above, the better the PCD stability.

[0226]

[Table 3]

From the results shown in Table 3, the following is clear. The positive-type electron beam resist composition of the present invention has high resolution, good exposure margin and good depth of focus. Further, when the pattern profiles of Examples 1 to 26 were evaluated, the profiles were all good. However, when the comparative example was similarly evaluated, an inverse tapered profile was obtained.

B. X-ray irradiation evaluation The components shown in Examples 15 to 22 of Tables 1 and 2 were 0.1 μm
Was filtered through a Teflon filter to prepare a resist solution. This was uniformly coated on a silicon substrate having been subjected to hexamethyldisilazane treatment by a spin coater.
Heating and drying were performed on a hot plate at 20 ° C. for 90 seconds to form a 0.35 μm resist film.

This resist film is irradiated with an X-ray equal magnification irradiation device (XR
(S-200, gap value: 20 μm), and immediately after irradiation, heated on a hot plate at 110 ° C. for 90 seconds.
The film was further developed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, and dried. The line and space pattern and the contact hole pattern thus formed were observed with a scanning electron microscope, and the sensitivity and the resolving power were evaluated.

(Sensitivity Evaluation Method) Sensitivity indicates an irradiation dose for reproducing a contact hole pattern of 0.18 μm. (Resolving power evaluation method) The resolving power indicates a limit resolving power at an irradiation dose for reproducing a contact hole pattern of 0.18 μm.

[0231]

[Table 4]

The results show that the resist composition of the present invention has high sensitivity and high resolution in X-ray irradiation evaluation.

Next, examples of the negative electron beam and X-ray resist composition of the present invention will be described. (Synthesis Example of Negative Electron Beam and X-Ray Resist Composition of the Present Invention) Synthetic examples of constituent materials (1) Alkali-soluble resin 1) 5-vinyl-1,3-benzodioxole
8 g and 108.1 g of 4-hydroxystyrene in dry TH
After adding to 270 ml of F, the mixture was heated to 70 ° C. under a nitrogen stream. When the reaction temperature becomes stable, Vako Pure Chemicals V
-601 was added to 2.5% of the total number of moles of the monomer, and the reaction was started. After reacting for 6 hours, the reaction mixture is
It was diluted with F, poured into a large amount of hexane, and precipitated.
The powder was collected by filtration, re-precipitated twice with a THF-hexane system, and dried under reduced pressure to obtain a resin (P-1). As a result of GPC measurement, the molecular weight of the obtained resin was 17,000 as a weight average molecular weight (Mw) in terms of polystyrene.
The molecular weight dispersity (Mw / Mn) was 2.15. 2) Resin (P-5), (P-9), (P-11) and (P-7) precursors were obtained from resin (P-2) in the same manner as above.

3) 148.2 g of 5-vinyl-1,3-benzodioxole was added to 270 ml of dry THF, and the mixture was heated to 70 ° C. under a nitrogen stream. When the reaction temperature was stabilized, V-601 manufactured by Wako Pure Chemical Industries, Ltd. was added by 2.5% of the total number of moles of the monomers, and the reaction was started. After reacting for 6 hours, the reaction mixture was diluted with THF and poured into a large amount of hexane to precipitate. The powder was collected by filtration, re-precipitated twice with a THF-hexane system, and dried under reduced pressure to obtain a resin. 30 g of the obtained resin was dissolved in 300 ml of 1,2-dichloroethane. An appropriate amount of a solution of a boron tribromide-methyl sulfide complex in methylene chloride was added under a nitrogen stream, and the mixture was heated under reflux for 4 hours and then cooled. A small amount was sampled at regular intervals during the reaction, methanol was added to take out the polymer, and the reaction time was determined by a preliminary experiment in which the decomposition rate was monitored by ¹³ C-NMR. Methanol was added to the reaction solution, and the reaction solution was concentrated. Acetone / methanol was added to the residue to redissolve it, poured into degassed water, and the precipitated powder was collected by filtration and dried under reduced pressure to obtain resin (P-3). As a result of GPC measurement, the molecular weight of the obtained resin was 14,000 as a weight average molecular weight (Mw) in terms of polystyrene.
And the molecular weight dispersity (Mw / Mn) was 2.21. 4) A resin (P-4) was obtained in the same manner as described above.

5) A monomer obtained by protecting 4-vinylcatechol with imidazole and t-butyldimethylsilyl chloride in a conventional manner, 218.8 g, 5-vinyl-
29.6 g of 1,3-benzodioxole and 44.1 g of 4-t-butoxycarbonyloxystyrene were dried in TH.
After adding to 270 ml of F, the mixture was heated to 70 ° C. under a nitrogen stream. When the reaction temperature becomes stable, Vako Pure Chemicals V
-601 was added to 2.5% of the total number of moles of the monomer, and the reaction was started. After reacting for 6 hours, the reaction mixture is
It was diluted with F, poured into a large amount of hexane, and precipitated.
The powder was collected by filtration, re-precipitated twice with a THF-hexane system, and dried under reduced pressure to obtain a resin. The obtained resin is treated with fluorine ions by a conventional method, deprotected, and the resin (P
-6) was obtained. As a result of GPC measurement, the molecular weight of the obtained resin was 1 as a weight average molecular weight (Mw) in terms of polystyrene.
6,000, and molecular weight dispersity (Mw / Mn) = 2.
30. 6) In the same manner as described above, the resin (P-8) and the resin (P
-10) was obtained.

7) 20 g of the precursor polymer obtained by the same method as in the above 1) was dissolved in 80 ml of dry THF.
β-cyclohexylethyl vinyl ether 1.4 g, p
-Toluenesulfonic acid (10 mg) was added, the mixture was stirred at room temperature for 1 hour, and triethylamine was added. The reaction solution was poured into water, and the precipitated powder was collected by filtration, dried under reduced pressure, and resin (P-
7) was obtained. As a result of GPC measurement, the molecular weight of the obtained resin was 1 as a weight average molecular weight (Mw) in terms of polystyrene.
9,000, and molecular weight dispersity (Mw / Mn) = 2.
20.

8) 211.0 g (0.9 mol) of a monomer obtained by protecting 4-hydroxystyrene with imidazole and t-butyldimethylsilyl chloride by a conventional method.
1), 5-vinyl-1,3-benzodioxole
Using 8 g (0.1 mol) and 270 ml of degassed and dried THF, the reaction was started by breaking the glass seal using 12 mmol of s-butyllithium in a sealed tube at -78 ° C. 3
After reacting for an hour, the reaction was terminated with degassed methanol. It was put into a large amount of hexane, and the precipitated powder was collected by filtration, further re-precipitated twice in a THF-hexane system, and dried under reduced pressure to obtain a resin. The obtained resin was treated with fluorine ions by a conventional method and deprotected to obtain a resin (P-14). As a result of GPC measurement, the molecular weight of the obtained resin was 10,000 as a weight average molecular weight (Mw) in terms of polystyrene.
0, and the molecular weight dispersity (Mw / Mn) was 1.10. 9) In the same manner as above, a resin (P-15) was obtained.

(2) Crosslinking agent Synthesis of crosslinking agent [HM-1] 1- [α-methyl-α- (4-hydroxyphenyl) ethyl] -4- [α, α-bis (4-hydroxyphenyl) ethyl 20 g of benzene (Honshu Chemical Industry Co., Ltd. T
risp-PA) was added to a 10% aqueous potassium hydroxide solution, and the mixture was stirred and dissolved. Then, while stirring this solution, 3
60 ml of a 7% aqueous formalin solution was gradually added at room temperature over 1 hour. After stirring at room temperature for 6 hours, the mixture was thrown into a dilute sulfuric acid aqueous solution. The precipitate was filtered, washed sufficiently with water, and recrystallized from 30 ml of methanol to obtain 20 g of a white powder of a phenol derivative having a hydroxymethyl group [HM-1] having the following structure. The purity was 92% (liquid chromatography method).

[0239]

Embedded image

Synthesis of Crosslinking Agent [MM-1] 20 g of the phenol derivative having a hydroxymethyl group [HM-1] obtained in the above Synthesis Example was added to 1 liter of methanol, and the mixture was heated and stirred to dissolve. Next, 1 ml of concentrated sulfuric acid was added to this solution, and the mixture was heated under reflux for 12 hours. After the completion of the reaction, the reaction solution was cooled, and 2 g of potassium carbonate was added. After sufficiently concentrating this mixture, 300 ml of ethyl acetate was added. This solution was washed with water and concentrated to dryness to obtain 22 g of a white solid of a phenol derivative having a methoxymethyl group [MM-1] having the following structure. 90 purity
% (Liquid chromatography method).

[0241]

Embedded image

Further, the following phenol derivatives were synthesized in the same manner.

[0243]

Embedded image

[0244]

Embedded image

[0245]

Embedded image

[0246] 2. Examples [Examples, Comparative Examples] (1) Coating of resist Using the compounds constituting the present invention and the comparative compounds selected from the above synthesis examples, a solid content concentration of 1 was obtained at a composition shown in Table 5 below.
A 2% solution of the photoresist composition was prepared. Each sample solution was filtered through a 0.1 μm filter, and then applied on a silicon wafer using a spin coater.
The resist film was dried on a vacuum adsorption type hot plate at 10 ° C. for 90 seconds to obtain a resist film having a thickness of 0.3 μm.

[0247]

[Table 5]

The abbreviations used in Table 5 indicate the following. <Resin>

[0249]

Embedded image

[0250]

Embedded image

[0251]

Embedded image

P-12: Poly- (p-hydroxystyrene) (manufactured by Nippon Soda Co., Ltd., trade name: VP-8000) Mw 10,000 Mw / Mn = 1.2 P-13: Novolak resin / m-cresol / p-cresol = 45/55 (molar ratio) Mw 6,500

[0253]

Embedded image

[0254]

Embedded image

A. Evaluation of electron beam irradiation (Evaluation method) This resist film was irradiated using an electron beam lithography apparatus (acceleration voltage: 50 KeV). After the irradiation, each was heated for 60 seconds on a vacuum adsorption type hot plate at 110 ° C., and immersed in a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH) for 60 seconds.
Rinse with water for 2 seconds and dry. The cross-sectional shape of the obtained pattern was observed with a scanning electron microscope, and the resolving power, exposure margin, and depth of focus were evaluated. Table 6 shows the performance evaluation results.

(Sensitivity Evaluation Method) Sensitivity represents an irradiation dose for reproducing a 0.16 μm line and space (1/1) mask pattern. (Resolving power evaluation method) The resolving power indicates a limit resolving power at an irradiation dose for reproducing a 0.16 μm line and space (1/1) mask pattern.

(Evaluation method of PCD) The resist film obtained by the above method was left in an electron beam lithography apparatus under high vacuum for 120 minutes, and then a resist pattern was formed by the same method. Irradiation dose obtained by the above sensitivity evaluation method (in this case, there is no standing for 120 minutes under high vacuum after resist film formation,
(Immediate irradiation) at the same irradiation dose. The closer the critical resolution is to the critical resolution obtained above, the better the PCD stability.

[0258]

[Table 6]

[Explanation of Evaluation Results] As shown in the results of Table 6, the resist composition of the present invention in which two types of acid generators are combined has higher sensitivity and higher resolution, especially Compared to the resist composition of Comparative Example used alone, PC
D is good.

Further, with respect to Examples 2-1 to 2-16,
When the pattern profiles were evaluated, all the profiles were good. However, when a comparative example was similarly evaluated, a tapered profile was obtained.

The resins (P-14) and (P-1)
Using 5), the others were evaluated in the same manner as in Example 2-10. As a result, the resins (P-14) and (P-
Also in the case of using 15), a remarkable effect similar to that of Example 2-10 was obtained.

B. X-ray irradiation evaluation The components shown in Examples 2-1 to 2-5 of Table 5 were dissolved in 10.2 g of propylene glycol monomethyl ether acetate, and the solution was filtered through a 0.1 μm Teflon filter to prepare a resist solution. . This was uniformly applied to a hexamethyldisilazane-treated silicon substrate by a spin coater, and heated and dried on a hot plate at 120 ° C. for 90 seconds to form a 0.35 μm resist film.

The resist film is irradiated with an X-ray equal-magnification irradiation device (XR
(S-200, gap value: 20 μm), and immediately after irradiation, heated on a hot plate at 110 ° C. for 90 seconds.
The film was further developed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, and dried. The line and space pattern and the contact hole pattern thus formed were observed with a scanning electron microscope, and the sensitivity and the resolving power were evaluated.

(Sensitivity Evaluation Method) Sensitivity represents an irradiation dose for reproducing a 0.18 μm line-and-space (1/1) mask pattern. (Resolving power evaluation method) The resolving power indicates a limit resolving power at an irradiation dose for reproducing a 0.18 μm line and space (1/1) mask pattern.

[0265]

[Table 7]

The results show that the resist composition of the present invention has high sensitivity and high resolution even in X-ray irradiation evaluation.

[0267]

According to the electron beam and X-ray resist composition of the present invention, it is possible to provide an electron beam and X-ray resist composition having high sensitivity, high resolution and good PCD.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03F 7/032 G03F 7/032 7/038 601 7/038 601 H01L 21/027 H01L 21/30 502R F-term (Ref.) FD148 FD206 FD207 GP03

Claims (7)

[Claims] 1. A positive-working resin containing a resin having a group which (a) generates an acid upon irradiation with an electron beam or X-ray and (b) decomposes under the action of an acid to increase the solubility in an alkali developing solution. In an electron beam or X-ray resist composition, the compound (a) which generates an acid upon irradiation with an electron beam or X-ray is (a1) at least one sulfonic acid ester of N-hydroxyimide, and (a2) sulfonium sulfone A positive electron beam or X-ray resist composition comprising at least one onium sulfonate selected from the group consisting of acid salts and iodonium sulfonates. (C) having an acid-decomposable group, wherein the dissolution rate in an alkaline developer is increased by the action of an acid;
The positive electron beam according to claim 1, further comprising a low molecular weight dissolution inhibiting compound having a molecular weight of 3000 or less.
X-ray resist composition. (3) a compound capable of generating an acid upon irradiation with an electron beam or X-ray (c) having a group decomposable by an acid, wherein the dissolution rate in an alkaline developer is increased by the action of the acid. Molecular weight 300
0 or less low molecular dissolution inhibiting compound (d) In a positive electron beam or X-ray resist composition containing a resin which is insoluble in water and soluble in an alkali developing solution, the (a) irradiation of the electron beam or X-ray The compound generating an acid contains (a1) at least one sulfonic acid ester of N-hydroxyimide, and (a2) at least one onium sulfonic acid salt selected from the group consisting of sulfonium sulfonate and iodonium sulfonate. A positive electron beam or X-ray resist composition. 4. A compound which generates an acid upon irradiation with an electron beam or an X-ray. 4. A resin which is insoluble in water and soluble in an alkali developer. 4. A crosslinking agent which crosslinks the resin by the action of an acid. And (a) a compound capable of generating an acid upon irradiation with an electron beam or X-ray is (a1) at least one sulfonic acid ester of N-hydroxyimide, and (A2) A negative electron beam or X-ray resist composition comprising at least one onium sulfonate selected from the group consisting of sulfonium sulfonates and iodonium sulfonates. 5. An onium sulfonate selected from (a2) a sulfonium sulfonate and an iodonium sulfonate contains at least one compound represented by the following general formulas (I) to (III): The electron beam or X-ray resist composition according to claim 1. Embedded image In the formula, R _{1 to} R ₃₇ are the same or different and each represents a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a hydroxyl group, a halogen atom, or -S- Represents an _R38 group. R ₃₈ represents a linear, branched or cyclic alkyl group or aryl group. Further, two or more of R _{1 to} R ₁₅ , R _{16 to} R ₂₇ , and R _{28 to} R ₃₇ are combined to form one or two kinds selected from a single bond, carbon, oxygen, sulfur, and nitrogen. A ring including the above may be formed. And X ^- represents straight-chain may have a substituent group, branched, cyclic alkyl sulfonic acid anion, an aryl sulfonate anion may have a substituent, a camphor sulfonate anion. 6. The electron beam and X-ray resist composition according to claim 5, wherein said X ⁻ is an anion having a fluorine atom. 7. An electron beam or X-ray resist composition according to claim 1, further comprising (J) a cationically polymerizable compound.