JP3173368B2 - Polymer compound and chemically amplified positive resist material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for preparing a base resin, which has a significantly high alkali dissolution rate contrast before and after exposure, a high sensitivity and a high resolution, and The present invention relates to a polymer compound that provides a chemically amplified positive resist material suitable as a pattern forming material, and a chemically amplified positive resist material containing the compound.

[0002]

2. Description of the Related Art In recent years,
As the integration and speed of LSIs have been increasing and the pattern rules have been required to be finer, far-ultraviolet lithography is expected as a next-generation fine processing technology. The deep ultraviolet lithography can process 0.5 μm or less, and when a resist material having low light absorption is used, a pattern having a side wall nearly perpendicular to the substrate can be formed.

A recently developed acid-catalyzed chemically amplified positive resist material (described in Japanese Patent Publication No. 2-27660 and Japanese Patent Application Laid-Open No. 63-27829) is a highly luminous KrF excimer as a light source for far ultraviolet rays. Using a laser, sensitivity,
It is expected to be a particularly promising resist material for deep-ultraviolet lithography having high resolution and dry etching resistance and excellent characteristics.

As such a chemically amplified positive resist material, a two-component system comprising a base polymer and an acid generator, and a three-component system comprising a base polymer, an acid generator and a dissolution controlling agent having an acid labile group are available. Are known.

For example, Japanese Patent Application Laid-Open No. Sho 62-115440 proposes a resist material comprising poly-4-tert-butoxystyrene and an acid generator, and a similar resist material is disclosed in Japanese Patent Application Laid-Open No. Hei 3-223858. T in the molecule
A two-component resist material comprising a resin having an tert-butoxy group and an acid generator. Further, Japanese Patent Application Laid-Open No. Hei 4-21258 discloses a polymethacrylate containing a methyl group, an isopropyl group, a tert-butyl group, a tetrahydropyranyl group and a trimethylsilyl group. A two-component resist material comprising hydroxystyrene and an acid generator has been proposed.

Further, Japanese Patent Application Laid-Open No. 6-100488 discloses poly "3,4-bis (2-tetrahydropyranyloxy) styrene", poly "3,4-bis (tert-butoxycarbonyloxy) styrene", A resist material comprising a polydihydroxystyrene derivative such as "3,5-bis (2-tetrahydropyranyloxy) styrene" and an acid generator has been proposed.

However, these resist materials have problems such as insufficient contrast of the dissolution rate of the resist film, unsatisfactory sensitivity and resolution, and insufficient process adaptability. At present, it has not yet been put to practical use, and improvement of these problems is desired.

[0008] The present invention has been made in view of the above circumstances,
When compounded in a resist material as a base resin, a polymer compound that provides a chemically amplified positive resist material having higher sensitivity, higher resolution, exposure latitude and process adaptability than conventional resist materials, and this polymer compound as a base resin An object of the present invention is to provide a chemically amplified positive resist material used as a resist.

[0009]

Means for Solving the Problems and Embodiments of the Invention As a result of intensive studies to achieve the above object, the present inventor has a repeating unit represented by the following general formula (1) by a method described later. Or a new polymer compound having a weight average molecular weight of 3,000 to 300,000 represented by the following general formula (2), and using these polymer compounds as a base resin, In addition to the added chemically amplified positive resist material, particularly the acid generator, the weight average molecular weight is 100 to 1,000, and the hydrogen atom of the phenolic hydroxyl group is 10 times on average due to the acid labile group.
A dissolution controlling agent comprising a compound substituted at a ratio of from 100% to 100%, or a compound having a weight average molecular weight of more than 1,000 and not more than 3,000 and having a phenolic hydroxyl group in the molecule, and converting the hydrogen atom of the phenolic hydroxyl group into an acid. A chemically amplified positive resist material containing a dissolution controlling agent consisting of a compound partially substituted with an unstable group at an average of more than 0% and not more than 60% on the whole, or a chemical obtained by further blending a basic compound with the resist. Amplified positive resist material has high sensitivity, high resolution, excellent exposure latitude, excellent process adaptability, high practicability, is advantageous for precision microfabrication, and provides a very effective resist material for VLSI etc. It has been found that a chemically amplified positive resist material can be obtained.

[0010]

Embedded image (Where R ¹ is a hydrogen atom or a methyl group, R ² is a hydrogen atom or an acid labile group, at least one is a hydrogen atom, and at least one is an acid labile group. N is 2 or 3) is there.)

[0011]

Embedded image

In the formulas (1) and (2), the acid labile group is a group represented by the following formula (16) or (17), a tetrahydropyranyl group, a tetrafuranyl group, or a trialkylsilyl group. is there.

Embedded image Wherein R ¹⁵ and R ¹⁶ are each independently a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, and R ¹⁷ is a linear or branched alkyl group having 1 to 10 carbon atoms. R ¹⁸ is a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, and a is 0 or 1
It is. )

In this case, the polymer compound having the repeating unit represented by the above general formula (1) has a part of the phenolic hydroxyl group protected by an acid labile group. When such a polymer compound is blended into a chemically amplified positive resist material as an alkali-soluble resin, strong hydrogen bonds are generated between molecules or between an acid generator and a dissolution controlling agent due to phenolic hydroxyl groups remaining in the molecule. In the patterning process of exposure, heating, and development, the dissolution rate of alkali in the unexposed area is strongly controlled, and in the exposed area, the acid labile groups of the base resin, which is the matrix, are decomposed, and the hydrogen bond is released. The dissolution rate in an aqueous solution is rapidly promoted.

[0014] For example, polydi-tert-butoxycarbonyloxystyrene in which all of the phenolic hydroxyl groups of the polypolyhydroxystyrene are protected by an acid labile group such as a tert-butoxycarbonyl group (tert-BOC group) is known. However, according to the study of the present inventor, this has poor adhesion to the substrate because there is no phenolic hydroxyl group. Also, if all of the phenolic hydroxyl groups of the polyhydric hydroxystyrene are protected by the acid labile groups of the tert-BOC group, a large amount of decomposed substances (isobutylene, carbon dioxide) generated after exposure may cause scum. Problem.

Further, the dissolution rate of the conventional partially tert-BOC-modified polyhydroxystyrene after decomposition is 3,000 °.
/ Sec, but the part ter according to the present invention
The dissolution rate of t-BOC-modified polypolyhydroxystyrene is 10,000 ° / sec, and the polymer compound of the present invention and a resist material containing the same have extremely high effects.

From these facts, the chemically amplified positive resist material using a polymer having a repeating unit represented by the above formula (1) as a base resin can dissolve exposed and unexposed portions of a resist film in an aqueous alkali solution. Is significantly higher than the conventional one, resulting in a resist material having high sensitivity and high resolution. Further, the polymer compound of the above formula (2) also has the same properties as described above. The chemically amplified positive resist material blended with a copolymer as a base resin has the above excellent performance,
In addition, it is possible to arbitrarily control the dimension of the pattern and the shape of the pattern by the composition, and it has been found that the resist is a chemically amplified positive resist material having excellent process adaptability, and has led to the present invention. It is.

That is, the present invention provides: (i) one or more kinds of repeating units represented by the above general formula (1), and a weight average molecular weight of 3,000 to 3;
(Ii) the polymer compound represented by the general formula (2), wherein the weight average molecular weight is 3,000 to 300,000. A polymer compound, (iii) a polymer compound according to (i) or (ii), which is a monodisperse polymer having a molecular weight distribution of 1.0 to 1.5, (iv) (A) an organic solvent, and (B) a base resin. (I) A chemically amplified positive resist material comprising the polymer compound according to any one of (i) to (iii), (C) an acid generator, (v) (A) an organic solvent (B) The polymer compound according to any one of (i) to (iii) as the base resin; (C) an acid generator; and (D) a dissolution controlling agent having a weight average molecular weight of 100 to 1,
000 and a compound having two or more phenolic hydroxyl groups in the molecule, in which the hydrogen atom of the phenolic hydroxyl group is substituted by an acid labile group at an average rate of 10 to 100%. (Vi) (A) an organic solvent; (B) a polymer compound according to any one of (i) to (iii) as a base resin; (C) an acid generator (E). A compound having a weight average molecular weight of more than 1,000 and not more than 3,000 as a dissolution controlling agent and having a phenolic hydroxyl group in the molecule and having a hydrogen atom of the phenolic hydroxyl group exceeding 0% as a whole due to an acid labile group. A chemically amplified positive resist material comprising a partially substituted compound in a proportion of 60% or less, (vii) (A) an organic solvent, (B) a base resin, ) To (weight average molecular weight as the polymer compound (C) an acid generator (D) dissolution controlling agent according to any one of iii) is 100 to 1,
000 and a compound having two or more phenolic hydroxyl groups in the molecule in which the hydrogen atom of the phenolic hydroxyl group is substituted by an acid labile group at an average rate of 10 to 100% as a whole. Agent having a weight average molecular weight of 1,000
The average of more than 0% and more than 60% of the hydrogen atom of the phenolic hydroxyl group of the compound having a phenolic hydroxyl group in the molecule of more than 0 to 3,000 or less by an acid labile group.
(Viii) The dissolution controlling agent of the component (D) is represented by the formulas (4) to (14) described below, wherein the chemically amplified positive resist composition contains a compound partially substituted in the following ratio. The chemically amplified positive resist according to (v) or (vii), wherein one or two or more compounds selected from compounds having a phenolic hydroxyl group are obtained by replacing a hydrogen atom of the phenolic hydroxyl group with an acid labile group. (Ix) The chemical according to (vi) or (vii), wherein the dissolution controlling agent of the component (ix) (E) is one or more compounds selected from compounds having a repeating unit represented by the above formula (15). (X) further comprising (F) a basic compound as an additive;
And (xi) the acid generator of the component (C) is an onium salt (i)
v) A chemically amplified positive resist material according to any one of the above items x to x.

Hereinafter, the present invention will be described in more detail. The polymer compound of the first invention of the present invention comprises one or more kinds of repeating units represented by the following general formula (1).

[0019]

Embedded image (Where R ¹ is a hydrogen atom or a methyl group, R ² is a hydrogen atom or an acid labile group, at least one is a hydrogen atom, and at least one is an acid labile group. N is 2 or 3) is there.)

Next, the polymer compound of the second invention of the present invention is a copolymer represented by the following general formula (2).

[0021]

Embedded image

[0022]

[0023]

Here, in the above equations (1) and (2),
Examples of the acid labile group include a group represented by the following formula (16) or (17), a tetrahydropyranyl group, a tetrafuranyl group,
Or a trialkylsilyl group.

[0025]

Embedded image Wherein R ¹⁵ and R ¹⁶ are each independently a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, and R ¹⁷ is a linear or branched alkyl group having 1 to 10 carbon atoms. R ¹⁸ is a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, and a is 0 or 1
It is. )

Examples of the linear or branched alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an iso-butyl group and a tert-butyl group. Examples of the alkyl group include a cyclohexyl group and the like.

Here, specific examples of the acid labile group represented by the above formula (16) include, for example, methoxyethyl group, ethoxyethyl group, n-propoxyethyl group, iso-propoxyethyl group, n-butoxyethyl Group, iso-butoxyethyl group, tert-butoxyethyl group, cyclohexyloxyethyl group, methoxypropyl group, ethoxypropyl group, 1-methoxy-1-methyl-ethyl group, 1
-Ethoxy-1-methyl-ethyl group and the like, and examples of the acid labile group of the above formula (17) include a tert-butoxycarbonyl group and a tert-butoxycarbonylmethyl group. Further, as the trialkylsilyl group, each alkyl group such as a trimethylsilyl group and a tri-tert-butyldimethylsilyl group has 1 to 1 carbon atoms.
6 are mentioned.

The high molecular compound having a repeating unit represented by the above formula (1) of the present invention can be obtained by reacting the compound represented by the formula (1) as described above.
May be composed of one kind of unit included in
It may be composed of more than one unit. In the compound represented by the formula (2), each unit (2a),
(2b), (2c) and (2d) each may be composed of one type of unit included in each unit, or may be composed of two or more types of units.

[0029]

Embedded image

Here, the polymer compound of the present invention preferably contains two or more acid labile groups in consideration of the characteristics of a chemically amplified positive resist material blended with the polymer as a base resin. In this case, as the two or more acid labile groups, a combination of the alkoxyalkyl group represented by the above formula (16) and the group represented by the above formula (17) is preferable.

In the above formulas (1) and (2), n
Is 2 or 3. By selecting 2 or 3 as n, a hydroxyl group is formed after the acid labile group is decomposed, but the acidity increases as the number of hydroxyl groups increases to 2 or 3, and the alkali dissolution rate can be arbitrarily controlled. Becomes m is 1, 2 or 3, but from the viewpoints of ease of synthesis and controllability of alkali dissolution rate, m =
It is preferably 2.

Further, in the equation (2), p and q are positive numbers,
r and s are 0 or positive numbers, and 0 <(p + q) / (p + q
+ R + s) ≦ 1, preferably 0 <(p + q) / (p + q
+ R + s) ≦ 0.7, more preferably (p + q) / (p
+ Q + r + s) is in the range of 0.05 to 0.7. p,
When q is 0, the contrast of the alkali dissolution rate decreases, and the resolution deteriorates. On the other hand, (p + q) / (p
If (+ q + r + s) exceeds 0.7, it may cause a change in film thickness, the generation of stress in the film or the generation of bubbles during alkali development, or the adhesion to the substrate may be poor due to a decrease in the number of hydrophilic groups.

The proportion of p in the total of p + q + r + s is more preferably 0.05 to 0.8 (molar ratio), particularly 0.05 to 0.5, and the proportion of q is 0.2
To 0.95 (molar ratio), particularly 0.3 to 0.95.
The preferred ranges of r and s are all 0 to 0.5, particularly 0.05 to 0.3.

In the polymer compound of the above formula (1) or (2), the content of the acid labile group affects the contrast of the dissolution rate of the resist film, and controls the dimension of the pattern and the shape of the resist material. It is related to characteristics.

Each of the polymer compounds of the above formulas (1) and (2) has a weight average molecular weight (the measuring method is as described later) of 3,000 to 300,000, preferably 30,0.
It needs to be 00 to 30,000. If the weight average molecular weight is less than 3,000, the resist material will have poor heat resistance. If it exceeds 300,000, the alkali solubility will decrease, and the footing phenomenon will easily occur after pattern formation. Note that in equation (2), p + q + r + s
Is a number with the high molecular compound as the above weight average molecular weight.

Further, in the above-mentioned polymer compound, when the molecular weight distribution (Mw / Mn) is wide, a low molecular weight or high molecular weight polymer is present, and when a large amount of low molecular weight polymer is present, heat resistance may be reduced. When a large amount of a high molecular weight polymer is present, some of the high molecular weight polymers are difficult to dissolve in alkali, and may cause tailing after pattern formation.
Therefore, as the pattern rule becomes finer, the influence of such molecular weight and molecular weight distribution tends to increase, so that in order to obtain a resist material suitably used for fine pattern dimensions, the molecular weight distribution of the high molecular compound is 1.0
It is preferably monodisperse, i.e., 1.5 to 1.5, particularly 1.0 to 1.3.

The polymer compound having a repeating unit represented by the formula (1) of the present invention can be obtained by subjecting a monomer represented by the following formula (i) to radical polymerization or living anion polymerization. Alternatively, after radical polymerization or living anion polymerization of the monomer of the following formula (ii), partial hydrolysis is performed to partially deprotect the protective group R ⁷ (at least one protective group remains and at least one hydroxyl group remains). (Deprotection so as to form an individual product). Further, when two or more kinds of monomers represented by the formula (i) or (ii) are copolymerized and the monomer of the formula (ii) is used, the monomer is partially hydrolyzed as described above, thereby obtaining the formula (1) Can be obtained.

[0038]

Embedded image (In the formula, R ⁷ is an acid labile group, and R ¹ , R ² , and n have the same meaning as described above.)

When the polymer compound of the formula (2) is obtained, the monomer of the above formula (i) and the monomer of the following formula (iii) and, if necessary, the monomers of the following formulas (iv) and (v) are radically A method of performing polymerization or living anion copolymerization may be employed. Each monomer may be 2 if necessary.
More than one species can be used.

[0040]

Embedded image(Where R¹, R^Three, R^Four , R^Five, M and k are the same as above.
Show the taste. )

In the case where the present invention is applied to a resist material having a fine pattern rule, monodispersion is desirable for the above-mentioned reasons. In order to obtain a monodisperse polymer compound, radical polymerization is generally performed. A method in which a polymer having a wide molecular weight distribution polymerized by, for example, separation and monodispersion, and a method in which monodispersion is performed by living anion polymerization can be adopted.
Since the former method of performing separation involves a complicated process, the latter living anionic polymerization method is suitably used. In addition, since some of the copolymers cannot be subjected to living anionic polymerization, there are copolymers in which radical polymerization is preferably used.

When the polymer compound of the present invention is obtained by radical (co) polymerization, first, radical polymerization of the monomer of the above formula is carried out by a usual method using a polymerization initiator. In this case, as the polymerization initiator, a commonly used one can be used in a usual amount, but an organic peroxide, particularly an organic peroxide having a 10-hour half-life of 40 to 90 ° C. (for example, lauroyl peroxide) Oxide and the like are more preferably used.

The radical polymerization is preferably performed in an organic solvent. Specific examples of the organic solvent used include aromatic hydrocarbons, cyclic ethers, and aliphatic hydrocarbon solvents (for example, benzene, toluene, tetrahydrofuran (THF), dioxane, tetrahydropyran, dimethoxyethane, n-hexane, cyclohexane, etc.) Although these mixed solvents are mentioned, it is particularly preferable to use acetone. The amount of the organic solvent used is usually preferably 10 to 50% by weight in terms of monomer concentration.

The radical polymerization conditions can be adjusted as appropriate, but it is preferable to carry out the reaction at a temperature 20 to 50 ° C. higher than the 10-hour half-life of the organic peroxide for 3 to 10 hours.

When the polymer compound of the present invention is produced by living anionic polymerization, it can be carried out using a known living anion polymerization initiator. It is preferable to use an organometallic compound among the anionic polymerization initiators. Examples of the organometallic compound include organic alkali metals such as n-butyllithium, sec-butyllithium, tert-butyllithium, sodium naphthalene, naphthalene potassium, anthracene sodium, α-methylstyrene tetramerge sodium, cumyl potassium, cumyl cesium, and the like. No. The amount of the living anionic polymerization initiator added is determined by the design molecular weight (= monomer weight /
(Moles of the initiator).

The living anionic polymerization of the above monomer is
Generally, it is performed in an organic solvent. Examples of the organic solvent to be used include the same solvents as in the case of the radical polymerization, and it is particularly preferable to use tetrahydrofuran.

The concentration of the monomer used for the polymerization is suitably from 1 to 30% by weight, and the reaction is desirably carried out under high vacuum or with stirring under an inert gas atmosphere such as argon or nitrogen. The reaction temperature can be arbitrarily selected from -78 ° C to the boiling point of the reaction solution to be used. Particularly, it is preferably -78 ° C to 0 ° C for a tetrahydrofuran solvent and room temperature when a benzene solvent is used.

The polymerization reaction can be carried out for about 10 minutes to 7 hours, and the polymerization reaction can be stopped by adding a terminator such as, for example, methanol, water or methyl bromide to the reaction system.

In the living anionic polymerization reaction, since the monomer reacts 100% and the molecular weight can be appropriately adjusted, the molecular weight distribution of the obtained polymer is monodisperse (Mw
/Mn=1.0 to 1.5).

The weight average molecular weight (Mw) can be easily calculated from the weight of the monomer used and the number of moles (number of molecules) of the initiator, and can be measured by a light scattering method. The number average molecular weight (Mn) can be measured using a membrane osmometer. Further, the molecular structure can be easily confirmed by an infrared absorption (IR) spectrum and a ¹ H-NMR spectrum, and the molecular weight distribution can be evaluated by gel permeation chromatography (GPC).

In particular, the compound of the present invention is obtained by subjecting the monomers of the following formulas (vi), (vii) and (v) to radical polymerization or living anion polymerization, followed by hydrolysis and further hydrolysis. For example, the first hydroxyl group of the above formula (16) is partially replaced with the first acid labile group of the above formula (16).
The method of 7) wherein the compound is protected by a second acid labile group by a chemical reaction can be suitably employed.

[0052]

Embedded image(In the formula, tBu represents a tert-butyl group;¹,
R^Two, R^Three, R^Four , R^Five, N, m, p, q, r, and s are as described above.
Indicates the same meaning. )

In the above reaction formula, the polymer represented by the formula (18), particularly preferably, having a weight average molecular weight of 3,0
With a molecular weight distribution of 1.0 to 1.5
Is obtained by hydrolyzing the tert-butyl group of the polymer of the formula (18), which is represented by the formula (19), and hydrolyzed as shown in the formulas (20) and (21) By protecting a part of the hydroxyl groups successively with the acid labile groups represented by R ² and R ³ , the desired monodispersion (i.e., the molecular weight distribution is 1.0 to 1.5);
The weight average molecular weight (that is, 3,000 to 300,00
0) can be obtained as a polymer compound represented by the formula (21).

That is, in the compound of the above formula (18),
When the tert-butyl group, which is a protecting group for the hydroxyl group, is hydrolyzed, an appropriate amount of an acid such as hydrochloric acid or hydrobromic acid is easily added dropwise in a mixed solvent of dioxane, acetone, acetonitrile, benzene, water, etc. It can be carried out. According to such a method, since the main chain of the polymer compound is not broken during the reaction or a cross-linking reaction does not occur between the molecules, the formula (1) in which the molecular weight distribution is easily controlled is obtained.
The polyhydroxystyrene derivative having a hydroxyl group of 9) can be obtained.

Further, protection by acid labile groups R ² and R ³
After removing the hydroxyl-protecting group by hydrolysis as described above, the reaction can be carried out by introducing acid labile groups R ² and R ³ by a chemical reaction.

This reaction is particularly effective for obtaining a polymer compound in which R ² is an alkoxyalkyl group. This alkoxyalkylation reaction is carried out by adding a hydrogen atom of a hydroxyl group of polyhydroxystyrene of the above formula to a vinyl group of an ether compound represented by the following formula using an acid as a catalyst to form a hydroxyl group of polyhydroxystyrene as shown by the following formula. (A ratio of p mol to 1 mol of all hydroxyl groups) is protected by an alkoxyalkyl group.

[0057]

Embedded image(Where R¹, R^Four, R^Five, R^Fifteen , R¹⁷, N, m, p,
q, r, and s have the same meanings as described above;¹⁹Is a hydrogen atom
Or a linear, branched or cyclic alkyl having 1 to 5 carbon atoms
Group. )

Here, examples of the ether compound of the above formula (22) include vinyl ether and propenyl ether. This reaction is preferably performed in the presence of a solvent such as dimethylformamide, tetrahydrofuran, or dimethylacetamide. Examples of the acid include hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid, and pyridinium p-toluenesulfonic acid. Is used, and its use amount is preferably 0.1 to 10 mol% with respect to 1 mol of all hydroxyl groups of the polyhydroxystyrene to be reacted. The reaction temperature is preferably from room temperature to 60 ° C, and the reaction time is usually from 1 to 20 hours.

When a part of the hydroxyl groups of the polyhydroxystyrene is methoxymethylated, NaOH may be used in the presence of a solvent such as dimethyl sulfoxide or tetrahydrofuran.
It is preferable to react an alkali hydride such as H and a halomethyl ether such as chloromethyl ether with polyhydroxystyrene. In this case, the amount of the alkali hydride used is preferably such that a predetermined methoxymethyl group is introduced with respect to 1 mol of all hydroxyl groups of the polyhydroxystyrene to be reacted. The reaction temperature is preferably from 0 to 50 ° C, and the reaction time is usually from 1 to 20 hours.

After the alkoxyalkylation reaction is performed, a tert-butoxycarbonylation reaction, a tert-butoxycarbonylmethylation reaction, and the like are performed to introduce the acid labile group R ³ .

Here, the tert-butoxycarbonylation reaction can be carried out by reacting the above partially alkoxyalkylated polyhydroxystyrene with ditert-butyl dicarbonate in a solvent such as pyridine or tetrahydrofuran. In this case, ditert-butyl dicarbonate is used in such an amount that q mole of tert-butoxycarbonyl group is introduced per 1 mole of all hydroxyl groups of the polyhydroxystyrene of the above formula. The reaction temperature is preferably from room temperature to 50 ° C, and the reaction time is usually from 30 minutes to 4 hours.

The tert-butoxycarbonylmethylation reaction is carried out by adding potassium-tert-butoxide and tert-butoxide to the above partially alkoxyalkylated polyhydroxystyrene in a solvent such as dimethyl sulfoxide or tetrahydrofuran.
The reaction can be carried out by reacting tert-butoxycarbonylmethyl bromide. In this case, the amount of potassium tert-butoxide used is tert-butanol per 1 mol of all hydroxyl groups of the polyhydroxystyrene of the above formula.
This is the amount in which the butoxycarbonylmethyl group is introduced in q moles. The amount of tert-butoxycarbonylmethyl bromide used is equimolar to that of potassium tert-butoxide, the reaction temperature is preferably room temperature to 50 ° C., and the reaction time is usually 20 minutes to 10 hours.

Further, the tetrahydropyranylation reaction can be carried out by reacting with dihydropyran in tetrahydrofuran, and the tetrahydrofuranylation reaction can be carried out by reacting with dihydrofuran in tetrahydrofuran. The alkylation reaction can be performed by reacting with isobutene in tetrahydrofuran. The trialkylsilylation reaction can be performed by reaction with a trialkylsilyl chloride in the presence of imidazole. In these cases, the reaction temperature is between room temperature and 5
0 ° C. is preferable, and the reaction time is usually 1 to 5 hours.

Of these methods, in particular, in this method, tert
A -butoxycarbonyl group or a tert-butoxycarbonylmethyl group is preferably introduced, whereby, for example, a polymer compound represented by the following general formula (24) can be obtained.

[0065]

Embedded image (Wherein, R ¹ , R ¹⁵ , R ¹⁶ , R ¹⁷ , X, n, m, p,
q, r, s, and a have the same meaning as described above. )

Further, the polymer compound of the present invention is obtained by subjecting a monomer of the following formula (viii) to radical polymerization or living anion polymerization to hydrolyze an acetal group of the obtained polymer of the formula (25), It can also be obtained by protecting a part with an appropriate acid labile group.

[0067]

Embedded image

Next, the chemically amplified positive resist composition of the present invention is characterized in that (I) (A) an organic solvent, (B) the above polymer compound as a base resin, and (C) an acid generator. (A) Organic solvent (B) Polymer compound as base resin (C) Acid generator (D) Weight average molecular weight as dissolution control agent 100 to 1,
000 and a compound having two or more phenolic hydroxyl groups in the molecule, wherein a hydrogen atom of the phenolic hydroxyl group is substituted by an acid labile group at an average rate of 10 to 100% as a whole. (III) (A) Organic solvent (B) Polymer compound as base resin (C) Acid generator (E) Weight average molecular weight exceeding 1,000 as dissolution controlling agent A compound having a phenolic hydroxyl group in the molecule of not more than 3,000, wherein the hydrogen atom of the phenolic hydroxyl group is partially substituted by an acid labile group at an average rate of more than 0% and not more than 60% as a whole. (IV) (A) an organic solvent (B) a polymer compound as a base resin (C) an acid generator (D) As a dissolution controlling agent, the weight average molecular weight is 100 to 1,
000 and a compound having two or more phenolic hydroxyl groups in the molecule in which the hydrogen atom of the phenolic hydroxyl group is substituted by an acid labile group at an average rate of 10 to 100% as a whole. Agent having a weight average molecular weight of 1,000
The average of more than 0% and more than 60% of the hydrogen atom of the phenolic hydroxyl group of the compound having a phenolic hydroxyl group in the molecule of more than 0 to 3,000 or less by an acid labile group.
It is preferable to use a chemically amplified positive resist material containing a partially substituted compound in the following ratio.

Here, the organic solvent (A) used in the present invention may be any organic solvent capable of dissolving the acid generator, the base resin and the dissolution controlling agent. Such organic solvents include, for example, cyclohexanone, methyl-
Ketones such as 2-n-amyl ketone, alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, propylene glycol monomethyl ether, ethylene Glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, ethers such as diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, Esters such as methyl-3-methoxypropionate and ethyl-3-ethoxypropionate are exemplified. It can be used alone or as a mixture of species, but is not limited thereto. In the present invention, among these organic solvents, diethylene glycol dimethyl ether and 1-ethoxy-2 which have the best solubility of the acid generator in the resist component are used.
-Propanol is preferably used.

The amount of the organic solvent used is 200 to 1,000 parts with respect to 100 parts (parts by weight, hereinafter the same) of the base resin.
Particularly, 400 to 800 parts is suitable. If the amount is less than 200 parts, the compatibility may be reduced and the film formability may be deteriorated.
If the amount exceeds 00 parts, when the resist film is formed, it may be too thin.

Further, examples of the acid generator (C) include onium salts, sulfonated compounds, halogen-containing compounds, triazine compounds and the like. Of these, onium salts and sulfonated compounds are preferred. Specific examples of the onium salt include triphenylsulfonium triflate derivatives, triphenylsulfonium tosylate derivatives, and the like.
It is not limited to these. Examples of the sulfonated product include an alkylsulfonic acid ester derivative and an azidosulfonic acid derivative, but are not limited thereto. The amount of the acid generator added is 100 base resin.
1 to 20 parts, preferably 2 to 10 parts, per part is desirable.

The resist composition of the present invention may further comprise (D) a dissolution controlling agent. As the dissolution controlling agent, the hydrogen atom of the phenolic hydroxyl group of the compound having a weight average molecular weight of 100 to 1,000 and having two or more phenolic hydroxyl groups in the molecule is averagely 10 to 100 due to the acid labile group. % Of the substituted compound is blended.

The weight average molecular weight of the above compound is 100 to
It is 1,000, preferably 150-800.

The substitution rate of the hydrogen atom of the phenolic hydroxyl group by the acid labile group is 10% or more, preferably 30% or more, of the total phenolic hydroxyl group on average, and 10% or more.
If less than the above, edge roughness mainly occurs. The upper limit is 100%, more preferably 80%.

In this case, as the compound having a phenolic hydroxyl group, compounds represented by the following formulas (4) to (14) are preferable.

[0076]

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[0077]

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[0078]

Embedded image (Where R ⁸ and R ⁹ are each a hydrogen atom or a carbon atom 1)
R ¹⁰ is a hydrogen atom or a linear or branched alkyl or alkenyl group having 1 to 8 carbon atoms, or-(R
¹⁴⁾ a _z -COOH, R ^11, R ¹² each represent an alkylene group having 1 to 10 carbon atoms, an arylene group, a carbonyl group, a sulfonyl group, an oxygen atom or a sulfur atom, R ¹³ is an alkyl group having 1 to 8 carbon atoms , An alkenyl group, a hydrogen atom, a phenyl group or a naphthyl group each substituted with a hydroxyl group, and R ¹⁴ is a linear or branched alkylene group having 1 to 10 carbon atoms. H is an integer of 0 to 3;
Or 1. x, y, x ′, y ′, x ″, y ″ are respectively x + y = 8, x ′ + y ′ = 5, x ″ + y ″
= 4 and has at least one hydroxyl group in each phenyl skeleton. )

In the above formulas, R ⁸ and R ⁹ are, for example, a hydrogen atom, methyl, ethyl, propyl, butyl, ethynyl, cyclohexyl, and R ¹⁰ are, for example, a hydrogen atom, methyl, ethyl , A propyl group, a butyl group, a cyclohexyl group or the like, or -COOH, -CH ₂
COOH, R ¹¹ and R ¹² include, for example, a methylene group, an ethylene group, a phenylene group, a carbonyl group, a sulfonyl group, an oxygen atom and a sulfur atom, and R ¹³ include, for example, a methyl group, an ethyl group, a butyl group, and a propyl group. , An ethynyl group,
Examples include a cyclohexyl group, a hydrogen atom, a phenyl group substituted with a hydroxyl group, and a naphthyl group.

Here, the acid labile group of the dissolution controlling agent includes the groups represented by the above formulas (16) and (17), tert-butyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkyl And a silyl group and a β-ketoalkyl group.

The compound (dissolution controlling agent) in which the phenolic hydroxyl group is partially substituted with an acid labile group is 0 to 50 parts, preferably 5 to 50 parts, per 100 parts of the base resin.
More preferably, it is 10 to 30 parts, and it can be used alone or in combination of two or more. If the amount is less than 5 parts, the resolution may not be improved. If the amount is more than 50 parts, the pattern may be reduced in film thickness and the resolution may be reduced.

The above-described dissolution controlling agent can be synthesized by chemically reacting a compound having a phenolic hydroxyl group with an acid labile group in the same manner as in the base resin.

The chemically amplified positive resist composition of the present invention comprises:
In place of, or in combination with, the dissolution controlling agent (D), the weight controlling agent (E) has a weight average molecular weight of 1,0.
The total number of hydrogen atoms of the phenolic hydroxyl group of the compound having a phenolic hydroxyl group in the molecule of more than 00 and not more than 3,000 is more than 0% by an acid labile group and more than 0% on average.
%, Preferably more than 0% and up to 40% of partially substituted compound. If it is 0%, a sufficient dissolution control effect cannot be obtained, and if it exceeds 60%, phase separation occurs between the polymers and the compatibility is lost.

In this case, the compound in which the hydrogen atom of the phenolic hydroxyl group is partially substituted with such an acid labile group includes:
One or more compounds selected from compounds having a repeating unit represented by the following general formula (15) are preferred.

[0085]

Embedded image (Where R represents an acid labile group, and b and c are numbers satisfying 0 <b / (b + c) ≦ 0.6, respectively)

Here, the acid labile group of the dissolution controlling agent includes an alkoxyalkyl group represented by the general formula (16), a group having a carbonyl group represented by the general formula (17), and a tert-butyl group. , A tetrahydropyranyl group, a triallylsilyl group, and a β-ketoalkyl group.

The amount of the dissolution controlling agent (E) is from 0 to 50 parts, more preferably from 1 to 50 parts, per 100 parts of the base resin.
It is preferred that the amount be 50 parts, more preferably 1 to 30 parts. If the amount is too small, the resolution may not be sufficiently improved. If the amount is more than 50 parts, the film of the pattern may be reduced, and the resolution may be reduced.

The dissolution controlling agent (E) as described above can be synthesized by chemically reacting a compound having a phenolic hydroxyl group with an acid labile group in the same manner as the base resin.

The dissolution controlling agent of component (D) and the dissolution controlling agent of component (E) may be used alone or in combination.

The resist composition of the present invention further comprises (F)
A basic compound can be blended as an additive.

As the basic compound to be blended as the additive (F), a compound capable of suppressing the diffusion rate when the acid generated from the acid generator diffuses into the resist film is suitable. Incorporation of a basic compound suppresses the diffusion rate of acid in the resist film to improve resolution, suppresses sensitivity changes after exposure, reduces substrate and environment dependency, reduces exposure margin and pattern Profiles and the like can be improved. Examples of such basic compounds include primary, secondary, and tertiary aliphatic amines, hybrid amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having a carboxyl group, and sulfonyl groups. Examples include a nitrogen-containing compound, a nitrogen-containing compound having a hydroxyl group, a nitrogen-containing compound having a hydroxyphenyl group, an alcoholic nitrogen-containing compound, and an amide derivative.

Specifically, as the primary aliphatic amine, ammonia, methylamine, ethylamine, propylamine, butylamine, pentylamine, amylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, laurylamine, Cetylamine, methylenediamine, ethylenediamine, tetraethylenediamine and the like are exemplified, and as the secondary aliphatic amine, dimethylamine, diethylamine, dipropylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine,
Examples thereof include dinonylamine, didecylamine, dimethylmethylenediamine, dimethylethylenediamine, and dimethyltetraethylenediamine. As tertiary aliphatic amines, trimethylamine, triethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, tetramethylmethylenediamine, tetramethylethylenediamine, tetramethyltetraethylenediamine, etc. Is exemplified.

Examples of the mixed amine include dimethylethylamine and methylethylpropylamine.
Specific examples of aromatic and heterocyclic amines include benzylamine, phenethylamine, benzyldimethylamine, and aniline derivatives (eg, aniline, N-methylaniline,
N-ethylaniline, N-propylaniline, N, N-
Dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, ethylaniline, propylaniline, trimethylaniline, 4-nitroaniline, dinitroaniline, etc.), toluidine derivatives (eg, toluidine, N, N-dimethyltoluidine) Quinoline, aminobenzoic acid, N-phenylphenyltolylamine, N-methyldiphenylamine, triphenylamine, phenylenediamine, naphthylamine, diaminonaphthalene, pyrrole derivatives (for example, pyrrole, methylpyrrole, dimethylpyrrole, N-methylpyrrole, etc.) ), Imidazole derivatives (eg, imidazole, 4-
Methylimidazole, 4-methyl-2-phenylimidazole, etc.), oxazole derivatives, thiazole derivatives,
Pyrazole derivatives, pyrrolidine derivatives (eg, pyrrolidine, N-methylpyrrolidone, N-methylpyrrolidine, etc.), pyrroline derivatives, pyridine derivatives (eg, pyridine, methylpyridine, ethylpyridine, propylpyridine, butylpyridine, 5-butyl-2-methyl) Pyridine, trimethylpyridine, triethylpyridine, phenylpyridine, 3-methyl-2-phenylpyridine, te
rt-butylpyridine, diphenylpyridine, benzylpyridine, methoxypyridine, butoxypyridine, dimethoxypyridine, 1-methyl-2-pyridone, 4-pyrrolidinylpyridine, 1-methyl-4-phenylpyridine, 2- (1-ethyl Propyl) pyridine, etc.), piperidine derivatives, pyrimidine derivatives, purine derivatives, quinoline derivatives, carbazole derivatives, indole derivatives, nicotinamide derivatives, adenosine derivatives, adenine derivatives, thiabenzol, diaminosulfone and the like.

Further, as the nitrogen-containing compound having a carboxyl group, amino acid derivatives (for example, nicotinic acid, alanine, arginine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, glycylleucine,
Leucine, methionine, phenylalanine, threonine, lysine, 3-aminopyrazine-2-carboxylic acid, methoxyalanine and the like are exemplified, a nitrogen-containing compound having a sulfonyl group, a nitrogen-containing compound having a hydroxyl group,
Nitrogen-containing compounds having a hydroxyphenyl group, alcoholic nitrogen-containing compounds such as 2-hydroxypyridine, aminocresol, thiamine naphthalene disulfonate,
Pyridinesulfonic acid, ethanolamine, diethanolamine, triethanolamine, diisopropylamine, triisopropylamine, tripropylamine, 1
-Aminobutane-2-diol, 1-aminopropane-
3-ol, 1-aminobutane-2-diol and the like are exemplified. As amide derivatives, formamide, N-
Methylformamide, N, N-dimethylformamide,
Acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide and the like are exemplified.

The compounding amount of the above-mentioned basic compound is as follows.
0 to 10 parts, preferably 0.001 to 10 parts per part
Parts, more preferably 0.01 to 1 part. If the amount is less than 0.001 part, the effect as an additive may not be sufficiently obtained, and if it exceeds 10 parts, the resolution and sensitivity may be reduced.

In addition to the above components, a surfactant for improving coating properties and a light absorbing material for reducing the influence of irregular reflection from the substrate can be added to the resist composition of the present invention. . In addition, the addition amount of the optional component can be a normal amount as long as the effect of the present invention is not impaired.

In this case, examples of the surfactant include perfluoroalkyl polyoxyethylene ethanol, fluorinated alkyl ester, perfluoroalkyl amine oxide, and perfluoroalkyl EO adduct, and the light absorbing material is diaryl sulfo. Oxides,
Examples include diaryl sulfone, 9,10-dimethylanthracene, 9-fluorenone and the like.

A pattern can be formed using the chemically amplified positive resist material of the present invention by employing a known lithography technique. For example, spin coating is performed on a silicon wafer, and 0.5 to 2 0.0 μm, pre-baked at 80-120 ° C.,
After exposure to high energy rays such as electron beams and X-rays, 7
Post-exposure baking (PEB) at 0 to 120 ° C. for 30 to 200 seconds, followed by development with an aqueous alkali solution. In addition, the material of the present invention is most suitable for fine patterning using 254 to 193 nm far ultraviolet rays and an electron beam among high energy rays.

[0099]

The chemically amplified positive resist material using the polymer compound of the present invention as a base resin is sensitive to high energy rays, excellent in sensitivity, resolution, plasma etching resistance, and heat resistance of the resist pattern. Is also excellent. Also, the pattern is less likely to overhang,
Excellent dimensional controllability. Therefore, the chemically amplified positive resist material of the present invention can be a resist material having a small absorption at the exposure wavelength of the KrF excimer laser due to these characteristics, and can easily form a fine and perpendicular pattern to the substrate. It can be formed and is suitable as a fine pattern forming material for VLSI manufacturing.

[0100]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Synthesis Examples, Examples, and Comparative Examples, but the present invention is not limited to the following Examples.

[Synthesis Example 1] 1 g in a 500 ml flask
Was charged, 75 g of 3-tert-butoxycarbonyloxy-4-hydroxystyrene, and 1,000 ml of acetone were charged. Then, the flask was purged with nitrogen, and the mixture was reacted at 90 ° C. for 5 hours to perform a polymerization reaction. went. After the completion of the polymerization reaction, the obtained polymer was washed with methanol and then dried, whereby a polymer represented by the following formula was obtained in a yield of 98%. Weight average molecular weight (Mw) and molecular weight distribution (Mw / M
n) is as shown in Table 1. When analyzed by ¹ H-NMR, a peak derived from a tert-BOC group was observed at 1.5 ppm (Polym1).

[Synthesis Examples 2 to 13] Polyms 2 to 13 were obtained in the same manner as in Synthesis Example 1 except that the following types of monomers were used.

The structure of the obtained polymer was as shown in the following formula, and the weight average molecular weight and molecular weight distribution of each polymer were as shown in Table 1. Synthesis Example 2 3-Tetrahydropyranyloxy-4-hydroxystyrene Synthesis Example 3 3-tert-butoxycarbonyloxymethyl-4-
Hydroxystyrene Synthesis Example 4 3-Methoxyethoxy-4-hydroxystyrene Synthesis Example 5 3-Trimethylsilyl-4-hydroxystyrene Synthesis Example 6 4-tert-butoxycarbonyloxy-3-hydroxystyrene 4-hydroxystyrene Synthesis Example 7 4-tert -Butoxycarbonyloxy-3-hydroxystyrene 3,4-dihydroxystyrene Synthesis Example 8 3-tert-butoxycarbonyloxy-4-hydroxystyrene 3,4-dihydroxystyrene 4-hydroxystyrene Synthesis Example 9 3-tert-butoxycarbonyloxy 4-hydroxystyrene 4-hydroxystyrene 4-tetra pyranyloxyethyl styrene synthesis example 10 3-tert-butoxycarbonyl-4-hydroxystyrene 4-hydroxystyrene 3,4 Di tert- butoxycarbonyloxystyrene Synthesis Example 11 3-tert- butoxycarbonyl-4-hydroxy-styrene-acrylic acid tert- butyl Synthesis Example 12 4-tert- butoxycarbonyl-3-hydroxy-styrene 3,4-dihydroxy styrene-hydroxystyrene Synthesis Example 13 4-tert-butoxycarbonyloxy-3-hydroxystyrene 3-tert-butoxycarbonyloxy-4-hydroxystyrene 3,4-dihydroxystyrene 4-hydroxystyrene 4-tert-butoxycarbonyloxystyrene

[Synthesis Example 14] In the polymerization, 700 ml of tetrahydrofuran as a solvent and 2 × 10 ^-3 mol of sec-butyllithium as an initiator were charged into a 2 L flask.
To this mixed solution was added 40 g of 3,4-ditert-butoxystyrene at −78 ° C., and the mixture was polymerized with stirring for 1 hour. The reaction solution turned red. The polymerization was completed by adding methanol to the reaction solution.

Next, the reaction mixture was poured into methanol,
The resulting polymer was precipitated, separated and dried to obtain 39 g of a white polymer [poly (3,4-ditert).
-Butoxystyrene)]. The obtained polymer had a weight average molecular weight of 1.8 × 10 ⁴ by a membrane osmotic pressure method.
g / mol. From the GPC elution curve, it was confirmed that the polymer was very monodisperse (Mw / Mn = 1.15) in terms of molecular weight distribution.

30 g of the above poly (3,4-ditert-butoxystyrene) was dissolved in 900 ml of acetone.
After adding a small amount of concentrated sulfuric acid at 7 ° C. and stirring for 7 hours, the mixture was poured into water to precipitate the polymer, followed by washing and drying. As a result, 20 g of a polymer was obtained. The weight average molecular weight of the obtained polymer is 1.3 × 10 ⁴ g / mol. Further, since no peak derived from a tert-butyl group was observed in ¹ H-NMR, it was confirmed that the obtained polymer was poly (3,4-dihydroxystyrene) having a narrow molecular weight distribution.

Further, 50 g of the obtained poly (3,4-dihydroxystyrene) was dissolved in 500 ml of pyridine.
18 g of di-tert-butyl dicarbonate with stirring at 45 ° C
Was added. After reacting for 1 hour, the reaction solution was added dropwise to 3 L of water to obtain a white solid. After filtration, this was dissolved in 50 ml of acetone and added dropwise to 2 L of water.
Vacuum dried to obtain a polymer. The resulting polymer is
^{From 1} H-NMR, tert-BOC of hydrogen atom of hydroxyl group
The conversion was 20% (Polym 14), the weight average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) were as shown in Table 1, and the GPC elution curve was as shown in FIG.

[Synthesis Example 15] In the polymerization, 700 ml of tetrahydrofuran as a solvent and 2 × 10 ^-3 mol of sec-butyllithium as an initiator were charged into a 2 L flask.
20 g of 4-tert-butoxystyrene and 3,4-ditert-butoxystyrene 2 were added to this mixed solution at -78 ° C.
A solution obtained by mixing with 0 g was added, and polymerization was carried out with stirring for 1 hour. The reaction solution turned red. The polymerization was completed by adding methanol to the reaction solution.

Next, the reaction solution was poured into methanol to precipitate the obtained polymer, which was separated and dried, whereby 39 g of a white polymer was obtained. According to the result of ¹³ C-NMR, the obtained polymer was a random copolymer composed of 50% 3,4-di-tert-butoxystyrene and 50% 4-tert-butoxystyrene. The weight average molecular weight is 1.8 × 10 ⁴
g / mol. Furthermore, from the GPC elution curve, a very monodisperse (Mw / Mn =
1.15) was confirmed to be a high polymer.

20 g of the above random copolymer of 3,4-ditert-butoxystyrene and 4-tert-butoxystyrene was dissolved in 300 ml of acetone, a small amount of concentrated hydrochloric acid was added at 60 ° C., and the mixture was stirred for 6 hours. The polymer was precipitated, washed and dried to obtain 16 g of a polymer. The weight average molecular weight of the obtained polymer is 1.3.
× 10 ⁴ g / mol. The GPC elution curve was as shown in FIG. 2, and it was confirmed that the polymer was a highly monodisperse polymer.

Since no peak derived from the tert-butyl group was observed from ¹ H-NMR, the obtained polymer was a copolymer of 3,4-dihydroxystyrene and 4-hydroxystyrene having a narrow molecular weight distribution. It was confirmed that there was.

The above 3,4-dihydroxystyrene and 4-
50 g of a random copolymer with hydroxystyrene was dissolved in 500 ml of tetrahydrofuran, a catalytic amount of p-toluenesulfonic acid was added, and then 27 g of ethyl vinyl ether was added while stirring at 20 ° C. After reacting for 1 hour, the mixture was neutralized with concentrated aqueous ammonia, and the neutralized reaction solution was added dropwise to 10 L of water to obtain a white solid. After filtration, this was dissolved in 500 ml of acetone, and 10 L of water was added.
, And vacuum-dried after filtration. From the ¹³ C-NMR of the obtained polymer, it was confirmed that the hydrogen atom of the hydroxyl group of the random copolymer of 3,4-dihydroxystyrene and 4-hydroxystyrene was ethoxyethylated by 24%.

Further, the obtained partially ethoxyethylated 3,3
50 g of a random copolymer of 4-dihydroxystyrene and 4-hydroxystyrene was dissolved in 500 ml of pyridine, and 8 g of ditert-butyl dicarbonate was added while stirring at 45 ° C. After reacting for 1 hour, the reaction solution was added dropwise to 3 L of water to obtain a white solid. After filtration, this was dissolved in 50 ml of acetone, dropped into 2 L of water, filtered, and dried under vacuum to obtain a polymer. The obtained polymer has a structure represented by Polym 15, and contains ¹ H-NM
From R, the ethoxyethylation rate of the hydrogen atom of the hydroxyl group of the random copolymer of 3,4-dihydroxystyrene and 4-hydroxystyrene is 24%, and the tert-BOC conversion rate is 1
The weight-average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) were as shown in Table 1.

[Synthesis Examples 16 to 22] Synthesis Example 14 or Synthesis Example 1 except that monomers of the types shown below were used.
In the same manner as in 5, Polyms 16 to 22 were obtained. Synthesis Example 16 3,4-Diethoxyethoxystyrene 3,4-Dihydroxystyrene Synthesis Example 17 2,3,4-Tritert-butoxycarbonyloxystyrene 2,3,4-Trihydroxystyrene Synthesis Example 18 3,4-Di tert-Butoxycarbonylmethyloxystyrene 3,4-dihydroxystyrene synthesis example 19 3,4-ditert-butoxycarbonyloxystyrene 3,4-dihydroxystyrene 4-hydroxystyrene 4-ethoxyethoxystyrene synthesis example 20 3,4-di tert-Butoxycarbonyloxystyrene 3,4-dihydroxystyrene 3,4-ethoxyethoxystyrene Synthesis Example 21 3,4-ditert-butoxycarbonylmethyloxystyrene 3,4-dihydroxystyrene 3,4-diethoxypropoxy Styrene Synthesis Example 22 3,4-ditert-butoxycarbonyloxystyrene 3,4-dihydroxystyrene 3,4-di-n-butoxyethoxystyrene

[0115]

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[0116]

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[0117]

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[0118]

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[0119]

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[0120]

[Table 1]

EXAMPLES, COMPARATIVE EXAMPLES, REFERENCE EXAMPLES Polymers 1 (Poly1) to Polymer 22 (Polym22) obtained in the above synthesis examples are used as base resins, and are represented by the following formulas (PAG1) to (PAG10). An acid generator and a dissolution controlling agent represented by the following formulas (DRR1) to (DRR14) and (DRR1 ′) to (DRR8 ′) in the composition shown in Table 2 in diethylene glycol dimethyl ether (DGLM) or 1-ethoxy-2-propanol ( EIPA), methyl-2-n-amyl ketone (M
AK), propylene glycol monomethyl acetate (PGMMA), propylene glycol monoethyl acetate (PGMEA) or ethyl lactate (EL) / butyl acetate (BA) to prepare a resist material,
Further, each composition was filtered through a 0.2 μm Teflon filter to prepare resist solutions.

For comparison, as shown in Table 5, a resist solution was prepared in the same manner as described above using a polymer represented by the following chemical formula (Polym23) as a base resin.

The obtained resist solution was spin-coated on a silicon wafer and applied to a thickness of 0.8 μm. Next, the silicon wafer was baked at 100 ° C. for 120 seconds using a hot plate. Use an excimer laser stepper (Nikon Corporation, NSR-2005E)
X8A, NA = 0.5) at 60 ° C. at 90 ° C.
After baking for 2 seconds and developing with an aqueous solution of 2.38% tetramethylammonium hydroxide, a positive pattern could be obtained. The obtained resist pattern was evaluated as follows. The results are shown in Tables 2 to 4. Evaluation method : First, the sensitivity (Eth) was determined. Then 0.3
The exposure amount for resolving a 5 μm line and space at a ratio of 1: 1 was defined as the optimum exposure amount (Eop), and the minimum line width of the separated line and space at this exposure amount was defined as the resolution of the evaluation resist. The shape of the resolved resist pattern was observed using a scanning electron microscope. Also, 0.
The unevenness (edge roughness) of the 25 μm line and space was measured with a scanning electron microscope.

The chemically amplified positive resist material of the present invention has good sensitivity, high resolution, good pattern shape and excellent dimensional control, excellent plasma etching resistance, and excellent heat resistance of the resist pattern. It was confirmed that.

[0125]

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[0126]

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[0127]

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[0128]

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[0129]

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[0130]

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[0131]

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[0132]

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[0133]

[Table 2]

[0134]

[Table 3]

[0135]

[Table 4]

[0136]

[Table 5]

[Brief description of the drawings]

FIG. 1 is a graph showing a GPC elution curve of a polymer substance obtained in Synthesis Example 14.

FIG. 2 is a graph showing a polymer substance GPC elution curve obtained in Synthesis Example 15.

Continuing from the front page (72) Inventor Junji Tsuchiya 28-1 Nishifukushima, Nishifukushima, Nakatsukushi-mura, Niigata Pref. Shin-Etsu Chemical Co., Ltd. 28-1 Shin-Etsu Chemical Co., Ltd. Synthetic Technology Laboratory (56) References JP-A-3-143904 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 12/00-12 / 36 C08F 112/00-112/36 C08F 212/00-212/36

Claims (11)

(57) [Claims] 1. One or two of the following general formula (1)
It has at least three kinds of repeating units and has a weight average molecular weight of 3.0
A polymer compound having a molecular weight of from 00 to 300,000. Embedded image Wherein R ¹ is a hydrogen atom or a methyl group, R ² is a hydrogen atom or an acid labile group, at least one is a hydrogen atom, and at least one is an acid labile group. n is 2 or 3.
The acid labile group is a group represented by the following formula (16) or (17), a tetrahydropyranyl group, a tetrafuranyl group,
Or a trialkylsilyl group. Embedded image Wherein R ¹⁵ and R ¹⁶ are each independently a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, and R ¹⁷ is a linear or branched alkyl group having 1 to 10 carbon atoms. R ¹⁸ is a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, and a is 0 or 1
It is. )] 2. The polymer compound according to claim 1, which is represented by the following general formula (2) and has a weight average molecular weight of 3,000 to 300,000. Embedded image Wherein R ¹ is independently a hydrogen atom or a methyl group, R ² is a hydrogen atom or an acid labile group, at least one is a hydrogen atom, at least one is an acid labile group, ³ is an acid labile group. R ⁴ is a hydrogen atom, R ⁵ is-
A COOX group (X is a hydrogen atom or an acid labile group) or (R ⁶ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms), or R ⁴ and R ⁵ are It may be. Further, each of the above units may be composed of one kind or two or more kinds. n is 2 or 3, and m and k are 1, 2 or 3, respectively. p and q are positive numbers, r and s are 0 or positive numbers, and satisfy 0 <(p + q) / (p + q + r + s) ≦ 1. p + q + r + s is a number used as the above weight average molecular weight. The acid labile group is a group represented by the following formula (16) or (17), a tetrahydropyranyl group, a tetrafuranyl group, or a trialkylsilyl group. Embedded image Wherein R ¹⁵ and R ¹⁶ are each independently a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, and R ¹⁷ is a linear or branched alkyl group having 1 to 10 carbon atoms. R ¹⁸ is a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, and a is 0 or 1
It is. )] 3. The polymer compound according to claim 1, which is a monodisperse polymer having a molecular weight distribution of 1.0 to 1.5. 4. A chemically amplified positive electrode comprising: (A) an organic solvent; (B) a polymer compound according to claim 1 as a base resin; and (C) an acid generator. Mold resist material. 5. (A) Organic solvent (B) Polymer compound according to any one of claims 1 to 3 as a base resin (C) Acid generator (D) Dissolution controlling agent having a weight average molecular weight of 100 to 100 1,
000 and a compound having two or more phenolic hydroxyl groups in the molecule, in which the hydrogen atom of the phenolic hydroxyl group is substituted by an acid labile group at an average rate of 10 to 100%. Characteristic chemically amplified positive resist material. 6. (A) an organic solvent; (B) a polymer compound according to any one of claims 1 to 3 as a base resin; (C) an acid generator; and (E) a dissolution controlling agent having a weight average molecular weight of 1, A compound having a phenolic hydroxyl group in the molecule of more than 3,000 and not more than 3,000, wherein the hydrogen atom of the phenolic hydroxyl group is partially substituted with an acid labile group at an average rate of more than 0% and not more than 60% as a whole. A chemically amplified positive resist material comprising: 7. (A) an organic solvent; (B) a polymer compound according to any one of claims 1 to 3 as a base resin; (C) an acid generator; and (D) a dissolution controlling agent having a weight average molecular weight of 100 to 100. 1,
000 and a compound having two or more phenolic hydroxyl groups in the molecule, wherein the hydrogen atom of the phenolic hydroxyl group is a group represented by the above formula (16), a group represented by the above formula (17), tert-butyl A compound which is substituted by an acid labile group selected from a group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a trialkylsilyl group and a β-ketoalkyl group at an average rate of 10 to 100% (E) As another dissolution controlling agent Weight average molecular weight of 1,000
In a compound having a phenolic hydroxyl group of more than 0 and not more than 3,000 and having a phenolic hydroxyl group in the molecule, the hydrogen atom of the phenolic hydroxyl group is represented by the group represented by the general formula (16) or the general formula (1)
Partially substituted with an acid labile group selected from the group represented by 7), tert-butyl group, tetrahydropyranyl group, triallylsilyl group and β-ketoalkyl group at a rate of more than 0% on average and 60% or less as a whole. A chemically amplified positive resist material comprising a compound. 8. The dissolution controlling agent of the component (D) is represented by the following formula (4):
A hydrogen atom of the phenolic hydroxyl group of one or more compounds selected from the compounds having a phenolic hydroxyl group represented by the formulas (14) to (14); And a tert-butyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a trialkylsilyl group and a β-ketoalkyl group.
Or a chemically amplified positive resist material according to 7. Embedded image Embedded image Embedded image (Where R ⁸ and R ⁹ are each a hydrogen atom or a carbon atom 1)
R ¹⁰ is a hydrogen atom or a linear or branched alkyl or alkenyl group having 1 to 8 carbon atoms, or-(R
¹⁴⁾ a _z -COOH, R ^11, R ¹² each represent an alkylene group having 1 to 10 carbon atoms, an arylene group, a carbonyl group, a sulfonyl group, an oxygen atom or a sulfur atom, R ¹³ is an alkyl group having 1 to 8 carbon atoms , An alkenyl group, a hydrogen atom, a phenyl group or a naphthyl group each substituted with a hydroxyl group, and R ¹⁴ is a linear or branched alkylene group having 1 to 10 carbon atoms. H is an integer of 0 to 3;
Or 1. x, y, x ′, y ′, x ″, y ″ are respectively x + y = 8, x ′ + y ′ = 5, x ″ + y ″
= 4 and has at least one hydroxyl group in each phenyl skeleton. ) 9. The dissolution controlling agent of the component (E) is represented by the following formula (1)
8. The chemically amplified positive resist composition according to claim 6, which is one or more compounds selected from compounds having a repeating unit represented by 5). Embedded image (Where R is a group represented by the general formula (16), a group represented by the general formula (17), a tert-butyl group,
Tetrahydropyranyl group, triallylsilyl group and β-
Represents an acid labile group selected from ketoalkyl groups, b and c
Are numbers each satisfying 0 <b / (b + c) ≦ 0.6. ) 10. The chemically amplified positive resist material according to claim 4, further comprising (F) a basic compound as an additive. 11. The chemically amplified positive resist composition according to claim 4, wherein the acid generator as the component (C) is an onium salt.