JPH08337616A - Polymer compounds and chemically amplified positive resist materials - Google Patents

Abstract

(57) [Summary] [Solution] One or two represented by the following general formula (1).
Having at least one repeating unit and having a weight average molecular weight of 3,0
A high molecular compound, which is 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 [Effect] The chemically amplified positive resist material using the polymer compound of the present invention as a base resin is sensitive to high energy rays, has excellent sensitivity, resolution, and plasma etching resistance, and has a high heat resistance of the resist pattern. It is also excellent in sex.
In addition, the pattern is unlikely to be overhanging and has excellent dimensional controllability. Therefore, the chemically amplified positive type resist material of the present invention can be a resist material having a small absorption particularly at the exposure wavelength of the KrF excimer laser due to these characteristics, and can easily form a fine pattern perpendicular to the substrate. It can be formed, and is suitable as a fine pattern forming material for VLSI manufacturing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention, when incorporated into a resist material as a base resin, has a significantly high alkali dissolution rate contrast before and after exposure, has high sensitivity and high resolution, and is particularly suitable for micro LSI manufacturing. 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 this compound.

[0002]

2. Description of the Related Art In recent years,
Along with higher integration and higher speed of LSIs, finer pattern rules are required, and far-ultraviolet lithography is expected as a next-generation fine processing technology. Far-ultraviolet lithography can also be processed to a size of 0.5 μm or less, and when a resist material having low light absorption is used, it is possible to form a pattern having side walls that are nearly vertical to the substrate.

A chemically amplified positive resist material using an acid catalyst developed in recent years (described in Japanese Examined Patent Publication (Kokoku) No. 2-27660 and Japanese Laid-Open Patent Publication No. 63-27829) discloses a KrF excimer having a high brightness as a light source of far ultraviolet rays. Using a laser, sensitivity,
It is expected as a particularly promising resist material for deep-UV lithography, which has excellent resolution and dry etching resistance and excellent characteristics.

Examples of such a chemically amplified positive resist material include a two-component system comprising a base polymer and an acid generator, a three-component system comprising a base polymer, an acid generator and a dissolution control agent having an acid labile group. Are known.

For example, Japanese Unexamined Patent Publication No. 62-115440 proposes a resist material comprising poly-4-tert-butoxystyrene and an acid generator, and Japanese Unexamined Patent Publication No. 3-223858 discloses a resist material similar to this proposal. T in the molecule
A two-component resist material comprising an ert-butoxy group-containing resin and an acid generator, and further, JP-A-4-21158 discloses a methyl group, an isopropyl group, a tert-butyl group, a tetrahydropyranyl group, and a trimethylsilyl group-containing poly. A two-component resist material composed of hydroxystyrene and an acid generator has been proposed.

Further, JP-A-6-100488 discloses that poly "3,4-bis (2-tetrahydropyranyloxy) styrene", poly "3,4-bis (tert-butoxycarbonyloxy) styrene", poly 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 dissolution rate of the resist film, unsatisfactory sensitivity and resolution, and insufficient process adaptability. At present, it has not been put into practical use, and improvement of these problems is desired.

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

[0009]

Means for Solving the Problems and Modes for Carrying Out the Invention As a result of earnest studies to achieve the above object, the present inventor has a repeating unit represented by the following general formula by the method described below, or A novel polymer compound represented by the general formula (2) or (3) and having a weight average molecular weight of 3,000 to 300,000 is obtained, and these polymer compounds are used as a base resin, and an acid generator, etc. In addition to the chemically amplified positive resist material, especially the acid generator,
The weight average molecular weight is 100 to 1,000, and the hydrogen atom of the phenolic hydroxyl group is 1 on average as a whole due to the acid labile group.
A dissolution control agent composed of a compound substituted at a ratio of 0 to 100% or a weight average molecular weight exceeding 1,000 and 3,000
A dissolution control agent comprising the following compound, in which a hydrogen atom of a compound having a phenolic hydroxyl group in the molecule is partially replaced by an acid labile group at an average of more than 0% and not more than 60% The chemically amplified positive resist material containing it and the chemically amplified positive resist material further compounded with a basic compound have high sensitivity, high resolution, excellent exposure latitude, excellent process adaptability, and high practicality. , It has been found that a chemically amplified positive type resist material is obtained which is advantageous for precise microfabrication and provides a very effective resist material for VLSI and the like.

[0010]

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 is there.)

[0011]

[Chemical 9]

[0012]

[Chemical 10] (However, in the formula, R ¹ , R ³ , R ⁴ , and R ⁵ have the same meanings as described above, and R ⁷ represents an acid labile group. Further, even if each unit is composed of one kind, It may be composed of two or more kinds, n and m have the same meanings as described above, t and q are positive numbers, r and s are 0 or positive numbers, and 0 <(t + q) / (t
+ Q + r + s) ≦ 0.7 is satisfied. t + q + r + s is a number which is the above weight average molecular weight. )

In this case, in the polymer compound having the repeating unit represented by the general formula (1), a part of the phenolic hydroxyl group is protected by an acid labile group. When such a polymer compound is added to a chemically amplified positive resist material as an alkali-soluble resin, a strong hydrogen bond is generated between molecules or between the acid generator and the dissolution control agent due to the phenolic hydroxyl group remaining in the molecule. However, in the patterning process of exposure, heating, and development, the dissolution rate with respect to alkali is strongly controlled in the unexposed area, and the acid labile group of the base resin that is the matrix is decomposed in the exposed area and the hydrogen bond is removed, resulting in alkali dissolution. The dissolution rate in an aqueous solution is rapidly accelerated.

Incidentally, for example, polyditert-butoxycarbonyloxystyrene is known in which all of the phenolic hydroxyl groups of polypolyhydroxystyrene are protected by an acid labile group such as tert-butoxycarbonyl group (tert-BOC group). However, according to the study by the present inventor, this has poor adhesion to the substrate due to the absence of phenolic hydroxyl groups. In addition, if all of the phenolic hydroxyl groups of polypolyhydroxystyrene are protected by the acid-labile group of the tert-BOC group, a large amount of decomposition products (isobutylene, carbon dioxide) generated after exposure will be generated, causing scum. There is a problem of becoming.

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

From these facts, the chemically amplified positive resist material using the polymer compound having the repeating unit of the above formula (1) as the base resin shows a dissolution rate of the exposed portion and the unexposed portion of the resist film in the alkaline aqueous solution. Has a much higher contrast than conventional ones, resulting in a resist material having high sensitivity and high resolution. Further, the polymer compound of the above formula (2) or (3) has the same characteristics as above. The chemically amplified positive resist material containing this copolymer as a base resin has the above-mentioned excellent performance, and the pattern size control and the pattern shape control can be arbitrarily performed by the composition. Yes,
The present invention has been completed by finding that it becomes a chemically amplified positive resist material excellent in process adaptability.

That is, the present invention comprises (i) one or more repeating units represented by the above general formula (1) and having a weight average molecular weight of 3,000 to 3.
(Ii) a polymer compound represented by the above general formula (2) and having a weight average molecular weight of 3,000 to 300,000; iii) a high molecular compound represented by the above general formula (3) and having a weight average molecular weight of 3,000 to 300,000; (iv) a monodisperse having a molecular weight distribution of 1.0 to 1.5. The polymer according to any one of (i), (ii) or (iii), which is a polymer, (v) (A) an organic solvent, (B) the polymer according to any one of (i) to (iv) as a base resin. Chemically amplified positive resist material comprising a compound (C) acid generator, (vi) (A) organic solvent (B) as a base resin, (i) to (iv) Polymer Compound (C) Acid Generator (D) Weight average molecular weight of 100 to as a solution control agent,
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 replaced with an acid labile group at an average of 10 to 100% as a whole. (Vi) (A) Organic solvent (B) Polymer resin (C) Acid generator (E) according to any one of (i) to (iv) as a base resin As a dissolution control agent, the weight average molecular weight is more than 1,000 and less than 3,000, and the hydrogen atom of the phenolic hydroxyl group of the compound having a phenolic hydroxyl group in the molecule exceeds 0% on average as a whole due to the acid labile group. A chemically amplified positive resist material containing a partially substituted compound at a ratio of 60% or less, (viii) (A) organic solvent (B) base resin (I) to any one polymer compound according to (iv) (C) an acid generator (D) weight average molecular weight as a dissolution control agent 100 to,
, And a compound having two or more phenolic hydroxyl groups in the molecule, in which the hydrogen atom of the phenolic hydroxyl group is replaced with an acid labile group at an average rate of 10 to 100% as a whole (E) The weight average molecular weight of the agent is 100
More than 0 and 3,000 or less, and the hydrogen atom of the phenolic hydroxyl group of the compound having a phenolic hydroxyl group in the molecule is more than 0% and 60% on average as a whole due to the acid labile group.
A chemically amplified positive resist composition containing a compound partially substituted in the following proportions, wherein the dissolution control agent of the component (ix) (D) is represented by the formula (4) to
(Vi) or (viii), wherein the hydrogen atom of the phenolic hydroxyl group of one or more compounds selected from the compound having a phenolic hydroxyl group represented by (14) is substituted with an acid labile group. The chemically amplified positive resist composition of (x), the dissolution control agent of the component (E) is one or more compounds selected from the compounds having the repeating unit represented by the above formula (15) (vii) or (Viii) Chemically amplified positive resist material, (xi) Further, (F) A chemical compound as described in any one of (v) to (x), wherein a basic compound is added as an additive. Provided are a positive resist material and (xii) the chemically amplified positive resist material according to any one of (v) to (xi), wherein the acid generator of the component (C) is an onium salt.

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

[0019]

[Chemical 11] (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 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]

[Chemical 12]

The polymer compound of the third invention of the present invention is a copolymer represented by the following general formula (3).

[0023]

[Chemical 13] (However, in the formula, R ¹ , R ³ , R ⁴ , and R ⁵ have the same meanings as described above, and R ⁷ represents an acid labile group. Further, even if each unit is composed of one kind, It may be composed of two or more kinds, n and m have the same meanings as described above, t and q are positive numbers, r and s are 0 or positive numbers, and 0 <(t + q) / (t
+ Q + r + s) ≦ 0.7 is satisfied. t + q + r + s is a number which is the above weight average molecular weight. )

Here, in the above equations (1) to (3),
Although various acid labile groups are selected, in particular, the following formula (1
It is preferably a group represented by 6) or (17), a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, a tetrahydropyranyl group, a tetrafuranyl group or a trialkylsilyl group.

[0025]

Embedded image (In the formula, 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 or branched alkyl group having 1 to 6 carbon atoms, and a is 0 or 1
Is. )

Examples of the linear or branched alkyl group include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, iso-butyl group, tert-butyl group and the like. A cyclohexyl group etc. can be illustrated as an alkyl group.

Specific examples of the acid labile group represented by the above formula (16) include methoxyethyl group, ethoxyethyl group, n-propoxyethyl group, iso-propoxyethyl group and n-butoxyethyl group. Group, iso-butoxyethyl group, tert-butoxyethyl group, cyclohexyloxyethyl group, methoxypropyl group, ethoxypropyl group, 1-methoxy-1-methyl-ethyl group, 1
Examples of the acid labile group of the above formula (17) include a tert-butoxycarbonyl group and a tert-butoxycarbonylmethyl group. Moreover, as the above-mentioned trialkylsilyl group, the number of carbon atoms of each alkyl group such as a trimethylsilyl group and a tri-tert-butyldimethylsilyl group is 1 to 1
6 are listed.

The polymer compound having the repeating unit represented by the above formula (1) of the present invention has the formula (1) as described above.
May be composed of one unit included in
It may be composed of more than one unit. In the compound represented by the formula (2) or (3), each unit (2a), (2b), (2c), (2d), or (3a), (3b), (3d) is each unit. May be composed of one unit or two or more units.

[0029]

[Chemical 15]

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

In the above formulas (1) to (3), n
Is 2 or 3. By selecting 2 or 3 as n, a hydroxyl group is generated 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 controlled arbitrarily. Becomes m is 1, 2 or 3, but m = in view of ease of synthesis, controllability of alkali dissolution rate, etc.
It is preferably 2.

Further, in the equation (2), p and q are positive numbers,
r and s are 0 or a positive number, 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. On the other hand, in the formula (3), t and q are positive numbers, r and s are 0 or positive numbers, and 0 <(t + q) / (t + q + r + s) ≦
0.7, more preferably (t + q) / (t + q + r +
s) is in the range of 0.05 to 0.7. p, q, t are 0
In that case, the contrast of the alkali dissolution rate decreases and the resolution deteriorates. On the other hand, (p + q) / (p + q +
If (r + s) or (t + q) / (t + q + r + s) exceeds 0.7, the film thickness changes or film stress or bubbles are generated during alkali development, and the hydrophilic group is reduced, resulting in poor adhesion to the substrate. May be inferior to.

Note that p + q + r + s or t + q + r + s
The ratio of p and t in the whole is more preferably 0.
05-0.8 (molar ratio), especially 0.05-0.5, and the ratio of q is 0.2-0.95 (molar ratio), especially 0.1.
It is 3 to 0.95. The preferred range of r and s is 0 to 0.5, particularly 0.05 to 0.3.

In the polymer compound of the above formula (1), (2) or (3), the content of the acid labile group affects the contrast of the dissolution rate of the resist film, and the pattern dimension control, the pattern shape, etc. It relates to the characteristics of the resist material.

The polymer compound of the above formula (1), (2) or (3) has a weight average molecular weight (measurement method is as described later) of 3,000 to 300,000, preferably 3,000. Must be ~ 30,000. If the weight average molecular weight is less than 3,000, the resist material will be inferior in heat resistance, and if it exceeds 300,000, the alkali solubility will be lowered, and the trailing phenomenon tends to occur after pattern formation. Note that in equations (2) and (3),
p + q + r + s or t + q + r + s is a number in which the polymer compound has the above weight average molecular weight.

Further, in the above-mentioned polymer compound, when the molecular weight distribution (Mw / Mn) is wide, there are low molecular weight and high molecular weight polymers, and when there are many low molecular weight polymers, the heat resistance may decrease. However, when a large amount of high-molecular weight polymer is present, it includes one that is difficult to dissolve in an alkali, which may cause tailing after pattern formation.
Therefore, since the influence of such molecular weight and molecular weight distribution is likely to increase as the pattern rule becomes finer, in order to obtain a resist material suitable for use in fine pattern dimensions, the molecular weight distribution of the polymer compound is 1.0
It is preferable that the monodispersion is about 1.5, especially 1.0 to 1.3.

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

[0038]

[Chemical 16](In the formula, R¹, R², R⁷ , N has the same meaning as above.
You )

In order to obtain the polymer compound of the formula (2), the monomer of the above formula (i) and the monomer of the following formula (iii) and, if necessary, the monomer of the following formula (iv) or (v) are radically copolymerized. When the polymer compound of the formula (3) is obtained by employing the method of polymerization or living anion copolymerization, the monomer of the formula (ii) and the formula (iii), and optionally the formula (i).
A method of radical copolymerization or living anion copolymerization of the monomers v) and (v) can be adopted. If necessary, two or more kinds of each monomer can be used.

[0040]

[Chemical 17](In the formula, R¹, R³, R^Four , R^Five, M, k have the same meanings as above
Show the taste. )

Here, especially when it is applied to a resist material having a fine pattern rule, it is desirable that it is monodisperse for the above reason, and in order to obtain a monodisperse polymer compound, radical polymerization is generally used. It is possible to adopt a method of separating a polymer having a wide molecular weight distribution polymerized by, for example, to make it monodisperse, and a method of making it monodisperse by living anion polymerization.
Since the former method of fractionation involves complicated steps, the latter living anionic polymerization method is preferably used. Since some of the copolymers are incapable of living anionic polymerization, some copolymers are preferably used for radical polymerization.

When the polymer compound of the present invention is obtained by radical (co) polymerization, specifically, radical polymerization of the monomer of the above formula is first carried out by a usual method using a polymerization initiator. In this case, as the polymerization initiator, those usually used 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 above radical polymerization is preferably carried out in an organic solvent. Specific examples of the organic solvent used include aromatic hydrocarbons, cyclic ethers, aliphatic hydrocarbon solvents (for example, benzene, toluene, tetrahydrofuran (THF), dioxane, tetrahydropyran, dimethoxyethane, n-hexane, cyclohexane, etc.) and These mixed solvents are mentioned, but it is particularly preferable to use acetone. Usually, the amount of the organic solvent used is preferably 10 to 50% by weight in terms of monomer concentration.

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

When the polymer compound of the present invention is produced by living anionic polymerization, it can be carried out by using a known living anion polymerization initiator. In particular, in order to obtain the monodispersed polymer compound, living Among the anionic polymerization initiators, it is preferable to use an organometallic compound. Examples of the organic metal compound include organic alkali metals such as n-butyllithium, sec-butyllithium, tert-butyllithium, sodium naphthalene, naphthalene potassium, anthracene sodium, α-methylstyrenetetramage sodium, cumyl potassium and cumylcesium. Can be mentioned. The addition amount of the living anion polymerization initiator is the designed molecular weight (= monomer weight /
It is calculated from the relationship of (the number of moles of the initiator).

Living anionic polymerization of the above monomers is
It is generally carried out in an organic solvent. As the organic solvent to be used, the same solvent as in the case of the above radical polymerization can be mentioned, but it is particularly preferable to use tetrahydrofuran.

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

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

In the above living anionic polymerization reaction, 100% of the monomers react and the molecular weight can be adjusted appropriately, so that 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. Furthermore, the molecular structure can be easily confirmed by infrared absorption (IR) spectrum and ¹ H-NMR spectrum, and the molecular weight distribution can be evaluated by gel permeation chromatography (GPC).

Here, in particular, the compound of the present invention is produced by radical polymerization or living anion polymerization of monomers of the following formulas (vi), (vii) and the following formula (v), followed by hydrolysis and further hydrolysis. The hydroxyl group is partially substituted by, for example, the first acid labile group of the above formula (16) and the above formula (1).
The method of manufacturing by protecting with a second acid labile group of 7) by a chemical reaction can be suitably adopted.

[0052]

[Chemical 18](In the formula, tBu represents a tert-butyl group, and R¹,
R², R³, R^Four , R^Five, N, m, p, q, r, s are
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
The molecular weight distribution is from 1.0 to 1.5 at 00 to 300,000
The tert-butyl group of the polymer represented by the formula (18) is hydrolyzed to obtain polyhydroxystyrenes represented by the formula (19), and then generated by hydrolysis as shown in the formulas (20) and (21). By partially protecting some of the hydroxyl groups with the acid labile groups represented by R ² and R ³ , the target monodisperse (that is, the molecular weight distribution is 1.0 to 1.5) is obtained,
The weight average molecular weight (that is, 3,000 to 300,000)
A polymer compound represented by the formula (21) having 0) can be obtained.

That is, in the compound of the above formula (18),
When hydrolyzing the tert-butyl group, which is the protective group for the hydroxyl group, it is easy to add an appropriate amount of acid such as hydrochloric acid or hydrobromic acid in a mixed solvent of dioxane, acetone, acetonitrile, benzene, water, etc. It can be carried out. According to such a method, the main chain of the polymer compound is not cleaved during the reaction and the crosslinking reaction between the molecules does not occur. Therefore, the formula (1
The polyhydroxystyrene derivative having a hydroxyl group of 9) can be obtained.

The protection by the acid labile groups R ² and R ³ is
After removing the hydroxyl-protecting group by hydrolysis as described above, the acid labile groups R ² and R ³ can be introduced 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 give a hydroxyl group of polyhydroxystyrene as shown by the following formula. A part (ratio of p mol to 1 mol of all hydroxyl groups) is protected with an alkoxyalkyl group.

[0057]

Embedded image(In the formula, R¹, R^Four, R^Five, R^Fifteen , R¹⁷, N, m, p,
q, r, and s have the same meanings as above, and R¹⁹Is a hydrogen atom
Or a linear, branched or cyclic alkyl group 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 carried out in the presence of a solvent such as dimethylformamide, tetrahydrofuran, dimethylacetamide, and the acid is hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid, p-toluenesulfonic acid pyridinium salt or the like. Is used, and the amount used is preferably 0.1 to 10 mol% with respect to 1 mol of all hydroxyl groups of polyhydroxystyrene to be reacted. The reaction temperature is preferably room temperature to 60 ° C., and the reaction time is usually 1 to 20 hours.

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

After carrying out the alkoxyalkylation reaction as described above, a tert-butoxycarbonylation reaction, a tert-butoxycarbonylmethylation reaction and the like are carried out in order to introduce the acid labile group R ³ .

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

The tert-butoxycarbonylmethylation reaction is carried out by adding potassium-tert-butoxide and t-butoxide to the partially alkoxyalkylated polyhydroxystyrene in a solvent such as dimethyl sulfoxide or tetrahydrofuran.
It can be carried out by reacting with ert-butoxycarbonylmethyl bromide. In this case, the amount of potassium-tert-butoxide used is tert-but with respect to 1 mol of all hydroxyl groups of the polyhydroxystyrene of the above formula.
It is the amount by which q mol of butoxycarbonylmethyl group is introduced. The amount of tert-butoxycarbonylmethyl bromide used is equimolar to 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 carried out by reacting with isobutene in tetrahydrofuran. The trialkylsilylation reaction can be carried out by reaction with a trialkylsilyl chloride in the presence of imidazole. In these cases, the reaction temperature is room temperature to 5
0 degreeC is preferable and reaction time is 1 to 5 hours normally.

Of these, particularly in this method, tert
It is preferable to introduce a -butoxycarbonyl group or a tert-butoxycarbonylmethyl group, and for example, a polymer compound represented by the following general formula (24) can be obtained thereby.

[0065]

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

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

[0067]

[Chemical 21]

Next, the chemically amplified positive resist composition of the present invention comprises [I] (A) an organic solvent (B) as a base resin and the above-mentioned polymer compound (C) an acid generator. [II] (A) Organic solvent (B) Base resin as above polymer compound (C) Acid generator (D) Dissolution control 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 replaced with an acid labile group at an average of 10 to 100% as a whole. [III] (A) Organic solvent (B) The above-mentioned polymer compound as a base resin (C) Acid generator (E) As a dissolution control agent, the weight average molecular weight exceeds 1,000. A compound having a phenolic hydroxyl group in the molecule of 3,000 or less and partially replacing the hydrogen atom of the phenolic hydroxyl group with an acid labile group at an average of more than 0% and not more than 60%. A chemically amplified positive type resist material comprising: [IV] (A) organic solvent (B) base resin, polymer compound (C) acid generator (D) As a dissolution control agent, the weight average molecular weight is 100 to 1,
, And a compound having two or more phenolic hydroxyl groups in the molecule, in which the hydrogen atom of the phenolic hydroxyl group is replaced with an acid labile group at an average rate of 10 to 100% as a whole (E) The weight average molecular weight of the agent is 100
More than 0 and 3,000 or less, and the hydrogen atom of the phenolic hydroxyl group of the compound having a phenolic hydroxyl group in the molecule is more than 0% and 60% on average as a whole due to the acid labile group.
It is preferable to use a chemically amplified positive resist material containing a compound partially substituted in the following proportions.

Here, the organic solvent (A) used in the present invention may be any organic solvent in which the acid generator, the base resin and the dissolution control agent can be dissolved. Examples of such an organic solvent include cyclohexanone and methyl-
Ketones such as 2-n-amyl ketone, alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol and 1-ethoxy-2-propanol, propylene glycol monomethyl ether, ethylene Ethers such as glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, Examples include esters such as methyl-3-methoxypropionate and ethyl-3-ethoxypropionate. 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, the same applies hereinafter) of the base resin.
Particularly, 400 to 800 parts is preferable. If the amount is less than 200 parts, the compatibility may be deteriorated and the film formability may be deteriorated.
If it exceeds 100 parts, the resist film may become too thin when formed.

Further, examples of the acid generator (C) include onium salts, sulfonates, halogen-containing compounds, triazine compounds and the like. Among them, onium salts and sulfonates are preferable. Specific examples of onium salts include triphenylsulfonium triflate derivatives and triphenylsulfonium tosylate derivatives.
It is not limited to these. In addition, examples of the sulfonated compound include, but are not limited to, alkyl sulfonate derivative and azido sulfonate derivative. The amount of acid generator added is 100
1 to 20 parts, especially 2 to 10 parts are desirable for the parts.

The dissolution control agent (D) may be further added to the resist material of the present invention. The dissolution control agent has a weight average molecular weight of 100 to 1,000, and the hydrogen atom of the phenolic hydroxyl group of the compound having two or more phenolic hydroxyl groups in the molecule is 10 to 100 on average as a whole due to the acid labile group. The compound substituted in the ratio of% is blended.

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

The substitution ratio of the hydrogen atom of the phenolic hydroxyl group with the acid labile group is 10% or more, preferably 30% or more, and preferably 10% or more of the whole phenolic hydroxyl group.
If it is less than, edge roughness mainly occurs. The upper limit is 100%, more preferably 80%.

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

[0076]

[Chemical formula 22]

[0077]

[Chemical formula 23]

[0078]

[Chemical formula 24] (However, in the formula, R ⁸ and R ⁹ are each a hydrogen atom or a carbon number 1
Is a linear or branched alkyl group or alkenyl group having 8 to 8 carbon atoms, and R ¹⁰ is a hydrogen atom or a linear or branched alkyl group or alkenyl group having 1 to 8 carbon atoms, or-(R
¹⁴ ) _z- COOH, R ¹¹ and R ¹² are each 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, and 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. Further, h is an integer of 0 to 3, and z is 0.
Or 1. x, y, x ', y', x ", and y" are x + y = 8, x '+ y' = 5, x "+ y", respectively.
= 4 and has at least one hydroxyl group in each phenyl skeleton. )

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

Here, as the acid labile group of the dissolution control agent, the groups represented by the above general formulas (16) and (17), a tert-butyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a trialkyl group. Examples thereof include a silyl group and a β-ketoalkyl group.

The compounding amount (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, relative to 100 parts of the base resin.
It is more preferably 10 to 30 parts, and can be used alone or in combination of two or more kinds. If the content is less than 5 parts, the resolution may not be improved, and if it exceeds 50 parts, the pattern film may be reduced and the resolution may be deteriorated.

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

The chemically amplified positive resist material of the present invention is
In place of or in combination with the dissolution control agent of the component (D), the weight average molecular weight of the dissolution control agent (E) is 1,0.
More than 00 and less than 3,000, and the hydrogen atom of the phenolic hydroxyl group of the compound having a phenolic hydroxyl group in the molecule is more than 0% on average as a whole due to the acid labile group and 60
%, Preferably more than 0% and less than 40% can be compounded with partially substituted compounds. When it is 0%, a sufficient dissolution control effect cannot be obtained, and when 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 by such an acid labile group is
One or more compounds selected from compounds having a repeating unit represented by the following general formula (15) are preferable.

[0085]

[Chemical 25] (However, in the formula, 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 control agent is an alkoxyalkyl group represented by the general formula (16), a group having a carbonyl group represented by the general formula (17), or a tert-butyl group. , A tetrahydropyranyl group, a triallylsilyl group, and a β-ketoalkyl group.

The amount of the dissolution control agent (E) blended is 0 to 50 parts, more preferably 1 to 50 parts, relative to 100 parts of the base resin.
The range is preferably 50 parts, and more preferably 1 to 30 parts. If the blending amount is too small, the resolution may not be sufficiently improved, and if it exceeds 50 parts, the film thickness of the pattern may be reduced and the resolution may be lowered.

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

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

Further, the resist material of the present invention comprises (F)
A basic compound can be added as an additive.

The basic compound to be added as the (F) additive is preferably a compound capable of suppressing the diffusion rate when the acid generated from the acid generator diffuses in the resist film. With the addition of a basic compound, the acid diffusion rate in the resist film is suppressed to improve the resolution, the sensitivity change after exposure is suppressed, and the dependency on the substrate and the environment is reduced, and the exposure margin and pattern are reduced. The profile etc. can be improved. Such a basic compound has primary, secondary, and tertiary aliphatic amines, hybrid amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having a carboxyl group, and sulfonyl groups. Examples thereof include nitrogen-containing compounds, nitrogen-containing compounds having a hydroxyl group, nitrogen-containing compounds having a hydroxyphenyl group, alcoholic nitrogen-containing compounds and amide derivatives.

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, 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 (for example, toluidine, N, N-dimethyltoluidine). Etc.), quinoline, aminobenzoic acid, N-phenylphenyltolylamine, N-methyldiphenylamine, triphenylamine, phenylenediamine, naphthylamine, diaminonaphthalene, pyrrole derivatives (for example, pyrrole, methylpyrrole, dimethylpyrrole, N-methylpyrrole, etc.). ), An imidazole derivative (eg, imidazole, 4-
Methylimidazole, 4-methyl-2-phenylimidazole, etc.), oxazole derivative, thiazole derivative,
Pyrazole derivative, pyrrolidine derivative (eg, pyrrolidine, N-methylpyrrolidone, N-methylpyrrolidine, etc.), pyrroline derivative, pyridine derivative (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 derivative, pyrimidine derivative, purine derivative, quinoline derivative, carbazole derivative, indole derivative, nicotinic acid amide derivative, adenosine derivative, adenine derivative, thiabenzol, diaminosulfone and the like.

Further, as nitrogen-containing compounds having a carboxyl group, amino acid derivatives (eg, nicotinic acid, alanine, arginine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, glycylleucine,
Examples include leucine, methionine, phenylalanine, threonine, lysine, 3-aminopyrazine-2-carboxylic acid, methoxyalanine, etc., a nitrogen-containing compound having a sulfonyl group, a nitrogen-containing compound having a hydroxyl group,
As a nitrogen-containing compound having a hydroxyphenyl group and an alcoholic nitrogen-containing compound, 2-hydroxypyridine, aminocresol, thiaminenaphthalene disulfonate,
Pyridinesulfonic acid, ethanolamine, diethanolamine, triethanolamine, diisopropylamine, triisopropylamine, tripropylamine, 1
-Aminobutane-2-diol, 1-aminopropane-
Examples include 3-ol and 1-aminobutane-2-diol. Examples of the amide derivative include formamide and N-
Methylformamide, N, N-dimethylformamide,
Examples include acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide and the like.

The amount of the above-mentioned basic compound to be added is such that the acid generator 1
0 to 10 parts, preferably 0.001 to 10 parts
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 lowered.

In addition to the above components, the resist composition of the present invention may contain, as an optional component, a surfactant for improving the coating property, a light absorbing material for reducing the influence of diffused reflection from the substrate, and the like. . 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, perfluoroalkylamine oxide, perfluoroalkyl EO adduct and the like, and examples of the light absorbing material include diarylsulfone. Oxide,
Diaryl sulfone, 9,10-dimethylanthracene, 9-fluorenone and the like can be mentioned.

A pattern can be formed by using the chemically amplified positive type resist material of the present invention by employing a known lithography technique, for example, spin coating on a silicon wafer to form a pattern of 0.5-2. After coating to 0.0 μm and prebaking at 80 to 120 ° C., deep UV,
After exposure by irradiating high energy rays such as electron beams and X-rays, 7
It can be carried out by post-exposure bake (PEB) at 0 to 120 ° C. for 30 to 200 seconds and then developing with an alkaline aqueous solution. The material of the present invention is particularly suitable for fine patterning with deep ultraviolet rays of 254 to 193 nm and electron beams among high energy rays.

[0099]

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

[0100]

EXAMPLES The present invention will be specifically described below by showing 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
Of lauryl peroxide, 75 g of 3-tert-butoxycarbonyloxy-4-hydroxystyrene, and 1,000 ml of acetone were charged, the flask was replaced with nitrogen, and the mixture was reacted at 90 ° C. for 5 hours to carry out a polymerization reaction. went. After 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 of this polymer
n) is as shown in Table 1, and 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 by the same method 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 rational formula, and the weight average molecular weight and molecular weight distribution of each were as shown in Table 1. Synthetic Example 2 3-Tetrahydropyranyloxy-4-hydroxystyrene Synthetic 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 For polymerization, 700 ml of tetrahydrofuran as a solvent and 2 × 10 ⁻³ mol of sec-butyllithium as an initiator were charged in a 2 L flask.
To this mixed solution, 40 g of 3,4-ditert-butoxystyrene was added at -78 ° C, and polymerization was carried out while stirring for 1 hour. The reaction solution turned red. Polymerization was completed by adding methanol to the reaction solution.

Then the reaction mixture is poured into methanol,
The polymer obtained was precipitated, separated and dried to give 39 g of a white polymer [poly (3,4-ditert.
-Butoxystyrene)] was obtained. The polymer obtained had a weight average molecular weight of 1.8 × 10 ^{4 as} determined by the membrane osmotic pressure method.
It was g / mol. From the GPC elution curve, it was confirmed that the polymer had a very high monodispersity (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,
A small amount of concentrated sulfuric acid was added at 0 ° C., the mixture was stirred for 7 hours, poured into water to precipitate the polymer, which was washed and dried to obtain 20 g of the polymer. The weight average molecular weight of the obtained polymer is 1.3 × 10 ⁴ g / mol. Further, since a peak derived from a tert-butyl group was not 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 ditert-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. This was filtered, dissolved in 50 ml of acetone, added dropwise to 2 L of water, filtered,
It was vacuum dried to obtain a polymer. The polymer obtained is
^{From 1} H-NMR, tert-BOC of hydrogen atom of hydroxyl group
The conversion was 20% (Polym14), 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 For polymerization, 700 ml of tetrahydrofuran as a solvent and 2 × 10 ⁻³ mol of sec-butyllithium as an initiator were charged in 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 mixed with 0 g was added, and the mixture was polymerized while stirring for 1 hour. The reaction solution turned red. 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 then separated and dried to obtain 39 g of a white polymer. According to the result of ¹³ C-NMR, the obtained polymer was a random copolymer composed of 50% 3,4-ditert-butoxystyrene and 50% 4-tert-butoxystyrene, and a membrane osmometry method. Has a weight average molecular weight of 1.8 × 10 ^4.
It was found to be g / mol. Furthermore, from the GPC elution curve, the molecular weight distribution is very monodisperse (Mw / Mn =
It was confirmed that the polymer was high in 1.15).

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

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

Further, the partial ethoxyethylation obtained 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. This was filtered, dissolved in 50 ml of acetone, added dropwise to 2 L of water, filtered, and vacuum dried to obtain a polymer. The obtained polymer has a structure represented by Polym 15 and has a structure of 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.
It was 1%, and 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 the following types of monomers are used.
Polym 16 to 22 were obtained in the same manner as in 5. 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-di tert-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]

[Chemical formula 26]

[0116]

[Chemical 27]

[0117]

[Chemical 28]

[0118]

[Chemical 29]

[0119]

Embedded image

[0120]

[Table 1]

Examples and Comparative Examples Polymer 1 (Polym1) obtained in the above synthesis example to polymer 22 (Poly)
ym22) is used as a base resin and the following formula (PAG
1) to (PAG10) and the following formulas (DRR1) to (DRR14) and (DRR1 ′) to (DRR8 ′) dissolution control agents having the composition shown in Table 2 and diethylene glycol dimethyl ether (DGL).
M) or 1-ethoxy-2-propanol (EIP
A), methyl-2-n-amyl ketone (MAK), propylene glycol monomethyl acetate (PGMM
A), propylene glycol monoethyl acetate (P
GMEA) or ethyl lactate (EL) / butyl acetate (BA) was dissolved to prepare a resist material, and each composition was filtered with a 0.2 μm Teflon filter to prepare a resist solution.

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

The resist solution thus obtained was spin-coated on a silicon wafer to a thickness of 0.8 μm. Then, this silicon wafer was baked at 100 ° C. for 120 seconds using a hot plate. This is an excimer laser stepper (Nikon, NSR-2005E
X8A, NA = 0.5) and exposed at 90 ° C. for 60
After baking for 2 seconds and development 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 2-4. 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 taken as the optimum exposure amount (Eop), and the minimum line width of the separated line and space in this exposure amount was taken as the resolution of the evaluation resist. The shape of the resolved resist pattern was observed using a scanning electron microscope. Also, 0.
The roughness of 25 μm line and space (edge roughness) was measured with a scanning electron microscope.

The chemically amplified positive resist composition of the present invention has good sensitivity and high resolution, has a good pattern shape and excellent dimensional controllability, is excellent in plasma etching resistance and resist pattern heat resistance. Was confirmed.

[0125]

[Chemical 31]

[0126]

Embedded image

[0127]

[Chemical 33]

[0128]

Embedded image

[0129]

Embedded image

[0130]

Embedded image

[0131]

Embedded image

[0132]

[Chemical 38]

[0133]

[Table 2]

[0134]

[Table 3]

[0135]

[Table 4]

[0136]

[Table 5]

[Brief description of 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 GPC elution curve of a polymer substance obtained in Synthesis Example 15.

Front page continuation (72) Inventor Toshinobu Ishihara 28-1 Nishifukushima, Kubiki Village, Nakakubiki District, Niigata Prefecture Shin-Etsu Chemical Co., Ltd.

Claims (12)

[Claims] 1. One or two represented by the following general formula (1):
Having at least one repeating unit and having a weight average molecular weight of 3,0
A high molecular compound, which is 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 is there.) 2. A polymer compound represented by the following general formula (2), which has a weight average molecular weight of 3,000 to 300,000. Embedded image 3. A polymer compound represented by the following general formula (3), which has a weight average molecular weight of 3,000 to 300,000. Embedded image (However, in the formula, R ¹ , R ³ , R ⁴ , and R ⁵ have the same meanings as described above, and R ⁷ represents an acid labile group. Further, even if each unit is composed of one kind, It may be composed of two or more kinds, n and m have the same meanings as described above, t and q are positive numbers, r and s are 0 or positive numbers, and 0 <(t + q) / (t
+ Q + r + s) ≦ 0.7 is satisfied. t + q + r + s is a number which is the above weight average molecular weight. ) 4. The polymer compound according to claim 1, which is a monodisperse polymer having a molecular weight distribution of 1.0 to 1.5. 5. A chemically amplified positive electrode comprising (A) an organic solvent (B) as a base resin, and (C) an acid generator as a polymer compound according to any one of claims 1 to 4. Type resist material. 6. The polymer compound according to claim 1, which is (A) an organic solvent (B) a base resin, (C) an acid generator (D) a dissolution controller, and 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 substituted with an acid labile group in an average of 10 to 100% as a whole. Characteristic chemically amplified positive resist material. 7. The polymer compound according to any one of claims 1 to 4, which is (A) an organic solvent (B) a base resin, (C) an acid generator, and (E) a dissolution controller having a weight average molecular weight of 1, Of the compound having a phenolic hydroxyl group in the molecule of more than 000 and 3,000 or less, and partially substituting the hydrogen atom of the phenolic hydroxyl group with an acid labile group as a whole at an average of more than 0% and not more than 60%. A chemically amplified positive resist composition containing: 8. The polymer compound according to any one of claims 1 to 4 as (A) organic solvent (B) base resin, (C) acid generator (D) as a dissolution control agent, and a weight average molecular weight of 100 to 1,
, And a compound having two or more phenolic hydroxyl groups in the molecule, in which the hydrogen atom of the phenolic hydroxyl group is replaced with an acid labile group at an average rate of 10 to 100% as a whole (E) The weight average molecular weight of the agent is 100
More than 0 and 3,000 or less, and the hydrogen atom of the phenolic hydroxyl group of the compound having a phenolic hydroxyl group in the molecule is more than 0% and 60% on average as a whole due to the acid labile group.
A chemically amplified positive resist material containing a compound partially substituted in the following proportions. 9. The dissolution control agent of the component (D) has the following formula (4):
9. The hydrogen atom of the phenolic hydroxyl group of one or more compounds selected from the compounds having a phenolic hydroxyl group represented by (14) to (14) is substituted with an acid labile group. Chemically amplified positive resist material. [Chemical 4] Embedded image [Chemical 6] (However, in the formula, R ⁸ and R ⁹ are each a hydrogen atom or a carbon number 1
Is a linear or branched alkyl group or alkenyl group having 8 to 8 carbon atoms, and R ¹⁰ is a hydrogen atom or a linear or branched alkyl group or alkenyl group having 1 to 8 carbon atoms, or-(R
¹⁴ ) _z- COOH, R ¹¹ and R ¹² are each 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, and 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. Further, h is an integer of 0 to 3, and z is 0.
Or 1. x, y, x ', y', x ", and y" are x + y = 8, x '+ y' = 5, x "+ y", respectively.
= 4 and has at least one hydroxyl group in each phenyl skeleton. ) 10. The dissolution control agent of component (E) is represented by the following formula (1)
The chemically amplified positive resist composition according to claim 7 or 8, which is one or more compounds selected from the compounds having the repeating unit represented by 5). [Chemical 7] (However, in the formula, R represents an acid labile group, and b and c are numbers satisfying 0 <b / (b + c) ≦ 0.6, respectively.) 11. The chemically amplified positive resist composition according to claim 5, further comprising a basic compound as an additive (F). 12. The chemically amplified positive type resist material according to claim 5, wherein the acid generator as the component (C) is an onium salt.