JPH0950126A - Resist composition and resist pattern forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a novel resist compsn. capable of forming a desired pattern by development with water as a developer and to provide a resist pattern forming method using the resist compsn. SOLUTION: This resist compsn. contains a base resin and an optical acid generating agent. A polymer forming the base resin contains repeating units each having a protected hydroxyl group. The repeating units may be units each having a substituent derived from glucofuranose having protected hydroxyl groups or units derived from vinyl alcohol having a protected hydroxyl group.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resist composition and a method for forming a resist pattern using the same. More specifically, the present invention relates to a novel chemically amplified resist composition that can be developed with water, which is a resist composition used particularly for ultrafine processing in the production of semiconductor devices, and the use thereof. And a method for forming a resist pattern.

[0002]

2. Description of the Related Art In recent years, the integration of semiconductor integrated circuits has advanced, and large-scale integrated circuits (LSIs) and very large-scale integrated circuits (VLSs) have been integrated.
I) has been put to practical use, and along with this, the minimum pattern of integrated circuits extends to the submicron region, and there is a tendency for further miniaturization in the future. To form a fine pattern, the substrate to be processed on which a thin film has been formed is covered with a resist, selective exposure is performed to form a latent image of the desired pattern, then development is performed to create a resist pattern, and this is used as a mask for dry etching. It is essential to use a lithographic technique in which the desired pattern is obtained by removing the resist after that.

As an exposure light source used in this lithography technique, g-line (wavelength 436 nm), i-line (wavelength 3)
65 nm) ultraviolet light is used, but with the miniaturization of patterns, far ultraviolet light, vacuum ultraviolet light, electron beam (EB), X-rays, etc., with shorter wavelengths are being used as light sources. ing. Particularly recently, an excimer laser (a KrF laser with a wavelength of 248 nm, a wavelength of 193 nm,
ArF laser) has attracted attention as an exposure light source,
It is expected to be effective for the formation of ultrafine patterns.
In this specification, when the term "radiation" is used, light from these various light sources, that is, ultraviolet rays,
It means far ultraviolet rays, vacuum ultraviolet rays, electron beams, X-rays, various laser beams and the like.

A chemically amplified resist material is a resist material that has recently been spotlighted as being particularly effective in forming a fine pattern. The chemically amplified resist material is a base resin having a protected alkali-soluble group,
An acid generator that generates an acid upon exposure to radiation is included, and the acid generated from the acid generator upon exposure causes the protective group of the alkali-soluble group of the main resin to be eliminated, and the main resin in the exposed area is soluble in alkali. Becomes Therefore, in the chemically amplified resist, an alkaline solution,
Generally, an organic alkaline aqueous solution is used.

In addition to the chemically amplified resist, various other resist materials have been used before the use of the chemically amplified resist material in the manufacture of semiconductor devices. Conventional resist materials other than chemically amplified resists utilize the difference in the solubility of the resin in the organic solvent between the exposed and unexposed areas, and in the case of positive resist, the resin in the exposed area and in the case of negative resist In the above, the resin in the unexposed area was dissolved in a solvent to develop a desired pattern.

[0006]

In recent years, there has been a demand for safety in the work environment in all industrial fields.
Various chemicals are also used in the field of semiconductor device manufacturing, and it is desired to reduce the use of harmful chemicals.

As described above, in the field of semiconductor device manufacturing, harmful chemicals such as organic solvents and organic alkaline aqueous solutions have been conventionally used for developing resist patterns. Allowing formation is extremely beneficial for safety management.

Therefore, the present invention eliminates the use of harmful chemicals such as organic solvents or organic alkaline aqueous solutions.
It is an object of the present invention to provide a new resist composition capable of developing a desired pattern by using water as a developing solution. Another object of the present invention is to provide a method of forming a resist pattern using this new resist composition.

[0009]

The resist composition of the present invention is basically a chemically amplified resist composition, and therefore contains a main resin and a photo-acid generator as essential components. After exposure to radiation, in the conventional chemically amplified resist, the base resin becomes alkali-soluble, so in contrast to the case where development was performed in an organic alkali aqueous solution, in the resist composition of the present invention, the base resin becomes water-soluble. Therefore, development with water becomes possible.

Thus, the resist composition of the present invention which becomes water-soluble after exposure to radiation is a composition containing a main resin and a photo-acid generator, and the polymer constituting the main resin protects the hydroxyl groups. It is characterized by containing a repeating unit.

In the first aspect, the base resin of the resist composition of the present invention has a repeating unit represented by the following formula.

[0012]

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In this formula, R ¹ is hydrogen, an alkyl group having 1 to 6 carbon atoms, halogen, or a halogenated alkyl group, and X is derived from glucofuranose having a hydroxyl group protected by the following formula. Is a group that has been

[0014]

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And n is 0 or an integer of 1 or more,
It is preferably 0 to 3. R ^{2 to} R ⁵ in the above formula (2) or (3) are an alkyl group having 1 to 6 carbon atoms or a halogenated alkyl group, and these may be the same or different. , R ^{6 to} R ⁹ are groups which are eliminated by an acid and may be the same or different.

The resin having the repeating unit represented by the above formula (1) may be a homopolymer of the repeating unit of the formula (1), and a copolymer containing this repeating unit and another repeating unit. It may be a combination.

In another aspect, the base resin of the resist composition of the present invention has the following formula as one of the repeating units.

[0018]

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A copolymer containing a repeating unit derived from vinyl alcohol having a protected hydroxyl group, represented by the formula (R ^I is a group capable of leaving by an acid).

Another repeating unit that can form the base resin of the resist material of the present invention together with the vinyl alcohol ether repeating unit represented by the above formula (4) is a copolymer unit with the repeating unit of this formula (4). Any unit that can make a coalesce can be used. Some examples of such repeating units are represented by the following formula, those derived from styrene or a derivative thereof,

[0021]

[Chemical 21]

(R ^II in this formula is hydrogen, having 1 to 12 carbon atoms.
Is an alkyl group, a halogen, or a halogenated alkyl group, wherein R ^{III to} R ^VII are hydrogen, an alkyl group having 1 to 12 carbon atoms, a halogen, a halogenated alkyl group, or a silicon atom having 1 to 9 carbon atoms. Or a group having a group having 1 to 9 carbon atoms and containing at least one silicon atom, represented by the following formula:

[0023]

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(Wherein R ^{VIII in} this formula is a group having 1 to 9 carbon atoms and containing at least one silicon atom) or an ether of a vinyl group and a substituted silyl group represented by the following formula: Derived repeat unit,

[0025]

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(Wherein R ^{IX in} this formula is a substituted silyl group having 1 to 9 carbon atoms), or one obtained from maleimide or a derivative thereof represented by the following formula:

[0027]

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(Wherein R ^X is hydrogen, R ^I , R ^VIII or R ^IX ) and the like.

The resist pattern forming method of the present invention comprises applying a solution of the resist composition of the present invention onto a substrate to be treated,
After pre-baking the formed resist film, the resist film is selectively exposed to radiation to form a latent image of a predetermined pattern, and then the resist film is exposed and baked, and then the latent image is developed with a developing solution. It is a method including developing.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION As described above, in one aspect, the base resin of the resist composition of the present invention has the following formula (1):
It has a repeating unit represented by

[0031]

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R ^{1 in} this formula is hydrogen, an alkyl group having 1 to 6 carbon atoms, halogen, or a halogenated alkyl group, and X is represented by the following formula (2) or (3): It is a group derived from glucofuranose with a protected hydroxyl group,

[0033]

[Chemical formula 26]

N is 0 or an integer of 1 or more,
It is preferably 0 to 3. In addition, R ² in the above formula
To R ⁵ are alkyl groups having 1 to 6 carbon atoms or halogenated alkyl groups, which may be the same or different, and R ^{6 to} R ⁹ are groups capable of leaving by an acid. And they may all be the same or different.

In the formula (2), the group protecting the hydroxyl group of the group derived from glucofuranose is represented by the following formula.

[0036]

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A typical example of the acid-removable group represented by these formulas is, but not limited to, an isopropylidene group represented by the following formula.

[0038]

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Examples of the groups capable of leaving by an acid represented by R ^{6 to} R ⁹ in the formula (3) are t-butyl group, t-amyl group, α, α-dimethylbenzyl group, trimethylsilyl group and tetrahydropyrani However, the group that is eliminated by an acid is not limited to these. The acid-eliminating groups exemplified here are represented by the following formulas, respectively.

[0040]

[Chemical 29]

The group represented by the formula (2) or (3), which is derived from glucofuranose protected with an acid leaving group, is a group of acid generated from the acid generator in the resist composition by exposure. When it is acted on, the above-mentioned acid-eliminating group is eliminated and a hydroxyl group is bonded, both of which become a group derived from glucofuranose of a polyhydric alcohol represented by the following formula (9).

[0042]

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As described above, the resin containing the repeating unit (acrylate unit) represented by the formula (1) has an ester group of this unit (the one represented by the above formula (2) or the formula (3)) in the exposed region. Becomes a group derived from glucofuranose of the polyhydric alcohol represented by the formula (9), so that the resin in the exposed region becomes soluble in water. Therefore, the resist composition of the present invention containing a resin containing the repeating unit represented by the formula (1) as a main component can be developed with water after exposure.

The resin having a repeating unit represented by the formula (1) may be a homopolymer of this repeating unit or a copolymer containing this repeating unit and another repeating unit. . In the case of a homopolymer, the etching resistance of the resist film formed from the resist composition is poor, so for the purpose of patterning subsequent applications not intended for etching and for etching in steps that do not require high etching resistance. It is valid.

In addition to the repeating unit represented by the formula (1),
The resist composition of the present invention can be used for a process involving an etching operation by adopting a copolymer resin having another repeating unit effective for improving the etching resistance of the resin. Therefore, the base resin of the resist composition of the present invention has a repeating unit obtained from an acrylic acid ester, an itaconic acid ester, or a fumaric acid ester having a group containing at least one silicon atom in the ester part, represented by the formula (1 ) And a repeating unit different from the repeating unit represented by. When a resin containing a repeating unit containing a group having at least one silicon atom is used, the resist composition of the present invention becomes resistant to oxygen plasma, and is therefore extremely useful as an upper layer resist in the two-layer resist method. It becomes something.

A copolymer containing, in addition to the first repeating unit represented by the formula (1), a second repeating unit having a group having at least one silicon atom in the ester portion is represented by, for example, the following formula. As described above, the ester portion of the second repeating unit may have a group derived from glucofuranose.

[0047]

[Chemical 31]

R ^{10 in} this formula has the same definition as R ^1.
10 and R ¹ may be the same or different, and R ¹¹ to
R ¹⁴ is a group having 1 to 6 carbon atoms and containing at least one silicon atom, k and m are positive integers,
n is as defined above and p is an integer of 0 or 1 or greater, preferably 0-3.

In this case, if the groups represented by R ^{11 to} R ¹⁴ are bonded to the oxygen (O) of the glucofuranose-derived group via a silicon atom, like a substituted silyl group (eg, trimethylsilyl group). In the glucofuranose-derived group, the R ^{11 to} R ¹⁴ groups are eliminated by the action of an acid after exposure and a hydroxyl group is bonded in place of the R ^{11 to} R ¹⁴ groups, so that the portion of the second repeating unit also becomes water-soluble. Therefore, in this case, the resist in the exposed area becomes more soluble in water.

Further, when all of the R ^{11 to} R ¹⁴ groups are bonded to oxygen (O) of the glucofuranose-derived group through a silicon atom, such as a substituted silyl group (trimethylsilyl group), Since these R ^{11 to} R ¹⁴ groups are eliminated after the exposure, the resist in the exposed region loses oxygen plasma resistance, while the resist in the unexposed region still retains oxygen plasma resistance. Therefore, in this case, dry etching of the resist film with oxygen plasma becomes possible.

In addition to the first repeating unit represented by the formula (1), a unit obtained from an acrylic acid ester, itaconic acid ester or fumaric acid ester having a group having at least one silicon atom in the ester part Other resins contained as the second repeating unit are represented by the following formulas (10) to (12).
It is represented by

[0052]

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R ^{10 in} this formula has the same definition as R ^1.
10 and R ¹ may be the same or different, R ¹¹ is as defined above, k and m are positive integers, n and p are as defined above, and q is 0 or 1
It is an integer of the above or more, and preferably 0 to 3.

Even when the resin having the structure of these formulas is contained, since the second repeating unit contains silicon,
The resist composition of the present invention also has oxygen plasma resistance, and therefore can be advantageously used as an upper layer resist of a two-layer resist method.

In addition to the first repeating unit represented by the formula (1), the resin of the copolymer having a second repeating unit effective for improving the etching resistance of the resin is a resin having an alicyclic ring in the ester portion. A unit having a substituent obtained from a group hydrocarbon and its derivative may be included as the second repeating unit. To give an example of a resin containing this second repeating unit,
In addition to the first repeating unit represented by the formula (1), it contains a repeating unit obtained from an acrylic acid ester, an itaconic acid ester, or a fumaric acid ester represented by the following formulas (13) to (15). .

[0056]

[Chemical 33]

[0057] R ¹ and R ¹⁰ in these formulas are as defined above, R ¹⁵ and R ¹⁶ is a substituent derived from an alicyclic hydrocarbon or a derivative thereof, R ¹⁵ and R ^When both ¹⁶ are present they may be the same or different and k, m, n have the previously defined meanings. R ¹⁵
And R ¹⁶ are, for example, adamantane or a derivative thereof, norbornane or a derivative thereof, cyclohexane or a derivative thereof, perhydroanthracene or a derivative thereof, perhydronaphthalene or a derivative thereof, tricyclo [5.2.1.0 ^2.6]. ] Decane or its derivative, bicyclohexane or its derivative, spiro [4,4] nonane or its derivative, spiro [4,5] decane or its derivative, tricyclopentadiene or its derivative, or fluorene or its derivative, etc. You can do it. Since all of these resins contain an alicyclic substituent, they have excellent etching resistance and are therefore suitable for use as a single-layer resist.

Further, the resin having a group derived from glucofuranose of the present invention in the molecule has an acrylate unit having an ester moiety containing a group obtained from an aromatic hydrocarbon and its derivative as another repeating unit. Can be included. Such a resin is represented by the following formula.

[0059]

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R ¹ and R ^{10 in} this formula are as defined above, R ¹⁷ represents a group derived from an aromatic hydrocarbon or a derivative thereof, and k, m and n are as defined above. Has meaning. Examples of the group obtained from the aromatic hydrocarbon represented by R ¹⁷ and its derivative are groups having a skeleton of benzene or its derivative, naphthalene or its derivative, and anthracene or its derivative. Since these resins also contain an aromatic group, they have excellent etching resistance and are therefore suitable for use as a single-layer resist.

The weight average molecular weight of the above-mentioned resin having a group derived from glucofuranose in the molecule is 1
If it exceeds 0,000, it may not be water-soluble even if it is eliminated by an acid, so that it is preferably 100,000 or less.
The preferable range of the weight average molecular weight is 2,000 to 30,
000. When the resin having a group derived from glucofuranose in the molecule is a copolymer, the formula (1) containing the glucofuranose-derived group in the copolymer
The proportion of the repeating unit represented by can account for 20 mol% or more of all the repeating units. This ratio is 20
If it is less than mol%, it may not be water-soluble even if a group which is eliminated by an acid is eliminated.

It has been found that the above-mentioned base resin having a group derived from glucofuranose in the molecule can form a positive resist pattern by radiation exposure without using a photoacid generator. For example, a resin having a structure of the following formula (weight average molecular weight = 20,000, in the formula, k: m = 1: 1)

[0063]

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Was dissolved in methyl isobutyl ketone without adding a photo-acid generator to obtain a 7% solution, and this solution was placed on a silicon wafer which was previously coated with a heat-cured novolak resist (film thickness 1.8 μm). Spin coating on 100 ℃
Then, the resist film is exposed to ArF excimer laser light, baked at 130 ° C. under reduced pressure for 1 minute, and then developed with pure water.
We were able to resolve the line and space pattern of μm. The threshold energy E _th of the irradiation dose at this time was 5.2 J / cm ² .

In another aspect, the base resin of the resist composition of the present invention has the following formula as one of the repeating units.

[0066]

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A copolymer containing a repeating unit derived from a vinyl alcohol protected with a hydroxyl group, represented by the formula (R ^{I in} this formula is a group capable of leaving by an acid). The group capable of leaving by an acid represented by R ¹ is, for example, a t-butyl group, a t-amyl group, an α, α-dimethylbenzyl group, as mentioned above in the description of the resin having a glucofuranose-derived group. A trimethylsilyl group, a tetrahydropyranyl group or the like may be used, but the group capable of leaving by an acid is not limited to these.

Another repeating unit that can form the base resin of the resist material of the present invention together with the vinyl alcohol ether repeating unit represented by the above formula (4) is a copolymer of the repeating unit of the above formula (4). Any unit that can make a coalesce can be used. Examples of the copolymer containing a vinyl alcohol ether repeating unit of the present invention, represented by the following formula, a copolymer with a repeating unit derived from styrene or a derivative thereof,

[0069]

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(R ^II in this formula is hydrogen, having 1 to 12 carbon atoms.
Is an alkyl group, a halogen, or a halogenated alkyl group, wherein R ^{III to} R ^VII are hydrogen, an alkyl group having 1 to 12 carbon atoms, a halogen, a halogenated alkyl group, or a silicon atom having 1 to 9 carbon atoms. Or m and n are positive integers), or the number of carbon atoms is 1 represented by the following formula.
To 9 and a copolymer with a repeating unit having a group containing at least one silicon atom,

[0071]

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(R ^{VIII in} this formula is a group having 1 to 9 carbon atoms and containing at least one silicon atom, and m,
n is a positive integer), or a copolymer of a repeating unit derived from an ether of a vinyl group and a substituted silyl group represented by the following formula,

[0073]

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(Wherein R ^IX is a substituted silyl group having 1 to 9 carbon atoms, m and n are positive integers), or a repeating unit represented by the following formula, which is obtained from maleimide or a derivative thereof. Copolymer with,

[0075]

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(R ^{X in} this formula is hydrogen, R ^I , R ^VIII or R ^IX , and m and n are positive integers) and the like.

Among these copolymers, the copolymer of the formula (16) with styrene or a derivative thereof has an aromatic ring in the molecule, and thus is a resin having good etching resistance. Therefore, a resist composition containing this resin is imparted with excellent etching resistance.

Since the copolymer represented by the formula (17) has a silicon atom in the molecule, the resist composition containing this copolymer resin has good oxygen plasma resistance, and therefore the upper layer of the two-layer resist method is used. It can be advantageously used as a resist.

In the copolymer represented by the formula (18), since the substituted silyl group of R ^IX is bonded to an oxygen atom to form a Si-O bond, the acid generated from the photo-acid generator upon exposure is exposed. By the action of, the substituted silyl group is eliminated and a hydrogen atom is bonded, that is, —OR ^IX is changed to —OH, so that both repeating unit portions of the copolymer are water-soluble in the exposed region. Therefore, the resist composition containing this resin has better sensitivity.

The copolymer with the maleimide represented by the formula (19) or a derivative thereof can be obtained by subjecting an acid generated by exposure to light when R ^X of the formula (19) is R ^I , that is, a group capable of leaving by an acid. R ^X -N bond polarity is increased becomes H-N bonds, to promote water solubility. Therefore, the sensitivity of the resist composition containing this resin becomes better. in this case,
Furthermore, if R ^X (that is, R ^I ) is a group containing silicon such as a trimethylsilyl group, silicon remains in the unexposed portion of the resist, so that the resist in this region is resistant to oxygen plasma. This allows dry etching of the resist film with oxygen plasma. When R ^X is R ^I , the resist composition is 2
It is also effective as an upper layer resist in the layer resist method.

When R ^{X of the} formula (19) is R ^VIII , that is, when it is a group containing silicon, it becomes an oxygen plasma resistant resin, and the resist composition containing this resin is used as the upper layer resist of the two-layer resist method. It is useful.

When R ^{X in the} formula (19) is R ^IX , that is, a substituted silyl group, R ^IX can be treated with an acid as described above.
Since the group is eliminated and both repeating units of the copolymer become water-soluble, the sensitivity of the resist composition containing this resin becomes better.

In the formula (19), R ^X may be hydrogen (H). In this case, the repeating unit obtained from the maleimide in which R ^X is hydrogen has a high polarity, and the vinyl ether unit is a copolymer in order to make the solubility difference between the exposed portion and the unexposed portion during development appropriate. It is preferably 70% or more of all repeating units in the molecule (the m / n ratio of the formula (19) is 70/30 or more).

In addition to this, a copolymer containing a repeating unit derived from a vinyl alcohol having a protected hydroxyl group is, for example, a copolymer with a fumaronitrile represented by the following formula.

[0085]

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(Wherein m and n are positive integers) or a copolymer with fumaric anhydride represented by the following formula

[0087]

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(M and n in the formula are positive integers).

The weight average molecular weight of the above-described resin containing a repeating unit derived from a vinyl alcohol having a protected hydroxyl group is not more than 100,000 because it may not be water-soluble even after elimination if it exceeds 100,000. Is preferred. The preferable range of the weight average molecular weight is 2,000 to 3
It is 0000. Further, in these resins, the formula (4)
The proportion of the repeating unit represented by can account for 50 mol% or more, preferably 80% or more, of all the repeating units. In general, if this ratio is less than 50%, it will not be water-soluble even after desorption. However, in the resin represented by the formula (19), when R ^X is hydrogen, the proportion of the repeating units derived from vinyl alcohol in all the repeating units is 70% or more as described above. Is preferred.

Each of the above resins used in the resist composition of the present invention can be easily prepared by a usual organic synthesis method using a suitable starting material. Therefore, the method of preparing these resins does not need to be described in detail in this specification. The following examples
Some examples of such synthesis techniques are shown.

The photoacid generator contained in the resist composition of the present invention may be any photoacid generator commonly used in chemically amplified resist compositions. Examples of suitable photoacid generators include sulfonium salts represented by the following formula:

[0092]

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Sulfonates represented by the following formula,

[0094]

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[0095]

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Iodonium salts represented by the following formula:

[0097]

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A halogen compound represented by the following formula,

[0099]

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Alternatively, it is various compounds represented by the following formula.

[0101]

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[0102]

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[0103]

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[0104]

[Chemical 51]

The resist composition of the present invention generally contains 0.1 to 20% by weight of the base resin, a photoacid generator. If the amount of the photo-acid generator is less than 0.1% by weight, an unpractical exposure dose is required to cause desorption, and if it is more than 20% by weight, the acid generator is not sufficiently mixed with the main resin and is precipitated. The preferred content of the photo-acid generator is in the range of 1 to 15% by weight of the base resin.

A method of forming a resist pattern using the resist composition of the present invention is as follows. A resist composition solution is applied onto a substrate to be treated, the formed resist film is prebaked, and then the resist film is selected for radiation. Exposure to form a latent image of the desired pattern, then post-exposure bake the resist film, and develop the latent image.

Next, this method will be described more specifically.
First, a solution of the resist composition of the present invention is applied on a substrate to be processed. The substrate to be used here may be any substrate normally used in semiconductor devices and other electronic devices, and specifically, a silicon substrate, or an oxide film, a polysilicon film, a nitride film on the surface thereof. A substrate provided with an aluminum film or the like can be given. These substrates may or may not already have circuitry built into them. These substrates may, in some cases, further improve the adhesiveness with the resist,
For example, it is preferable to pretreat with an adhesion promoter such as hexamethyldisilazane (HMDS). Also,
The substrate to be treated when using the resist composition of the present invention containing a silicon-containing polymer as a main resin in the two-layer resist method as described above means that the above substrate does not contain silicon atoms, and The resist material of the present invention is formed as an upper layer resist on which a layer of, for example, a heat-cured novolak resist is formed so as not to melt and mix with the upper layer resist.

The application of the resist solution can be performed by using a conventional coating apparatus such as a spin coater, a dip coater, a roller coater and the like. Although the thickness of the resist film to be formed can be widely changed depending on factors such as the purpose of use of the resist film, it is usually about 0.3 to 2.0.
It is in the range of μm.

Next, the formed resist film is pre-baked at a temperature of about 60 to 150 ° C., preferably 60 to 100 ° C. for about 60 to 180 seconds before selectively exposing it to radiation. A heating means such as a hot plate can be used for this pre-baking.

If a top coat film (protective film) is further formed on the resist film, for example, a solution of an olefin resin is applied on the resist film by spin coating, and the temperature is set to about 100 ° C. The topcoat film can be formed by baking at.

After prebaking the resist film, the resist film is selectively exposed to radiation by a conventional exposure device. Suitable exposure equipment is commercially available ultraviolet rays (far ultraviolet rays / vacuum ultraviolet rays)
An exposure apparatus, an X-ray exposure apparatus, an electron beam exposure apparatus, an excimer stepper, and the like. As the exposure condition, an appropriate condition can be selected each time.

Next, the resist film after exposure is subjected to post exposure bake (PEB). By this post-exposure bake, the elimination reaction of the protecting group using an acid as a catalyst is promoted, and the eliminated protecting group is vaporized and removed. This post-exposure bake can be performed in the same manner as the previous pre-bake. For example, the baking temperature is about 60-15.
It is 0 ° C, preferably about 100 to 150 ° C. When a top coat film is also used, it is peeled off by, for example, an organic solvent after the post-exposure bake and before the development.

After the post-exposure bake is completed, the latent image formed in the previous exposure step is developed with water as a developing solution. The developing time is not particularly limited, but is generally about 1
~ 5 minutes, preferably about 1-3 minutes.

After exposure to radiation, the resist composition of the present invention can be easily developed with water as described above. However, the resist composition of the present invention is not developable only with water. This resist composition can use, for example, a mixture of water and alcohol (preferably an alcohol having 1 to 5 carbon atoms), or an aqueous alkaline solution such as an organic alkaline aqueous solution as in the case of a conventional chemically amplified resist. An alkaline solution, or a mixture of an aqueous alkaline solution and an alcohol (preferably an alcohol having 1 to 5 carbon atoms) may be used. When a developing solution other than water is used, the solubility of the resin in the exposed area may be higher than that when only water is used, which may increase the sensitivity of the resist. Therefore, if environmental management permits, it may be advantageous to use these organic chemicals in addition to water.

In the resist composition of the present invention, when the main resin has a substituent containing a silicon atom, and this substituent is bonded to oxygen via the silicon atom,
That is, for example, when a substituent such as a trimethylsilyl group is bonded to oxygen, the exposed group is desorbed by the action of an acid generated from the photo-acid generator, and the unexposed area is replaced with the silicon. The contained substituent remains as it is, and only this region has oxygen plasma resistance. Therefore, by utilizing this, dry development (dry etching) of the resist film with oxygen plasma becomes possible. That is, in this case, it is possible to develop in a gas phase without using a developing solution.

As a result of the development, the resist film in the exposed area is removed and a desired resist pattern is formed. When an organic alkali aqueous solution or alcohol aqueous solution is used for the development, the resist pattern is rinsed with pure water after the development and then dried. When developing with water or dry developing with oxygen plasma, rinsing of the resist pattern after development is unnecessary.

[0117]

Next, the present invention will be further described with reference to examples.
Needless to say, these examples are merely examples and do not limit the present invention.

Example 1 1,2,5,6-di-O-isopropylidene-α-D-glucofuranose (DIPG)
5 times the amount of dehydrated tetrahydrofuran (TH)
It was dissolved in F), and a 1.1 times molar n-butyllithium hexane solution of DIPGL was added dropwise at room temperature. After the reaction system completely returned to room temperature, 1.1-fold molar amount of distillatively purified methacryloyl chloride was added dropwise to DIPGLF, and after the reaction system completely returned to room temperature, it was heated and refluxed at 70 ° C. for 2 hours. After that, water equivalent to THF was added to the reaction system to form an oil layer (T
HF layer) and the aqueous layer is taken up with diethyl ether.
The extract was extracted twice, and the extract was combined with the above oil layer, washed with saturated brine, dried over Glauber's salt, and the oil layer was concentrated. This was distilled under reduced pressure in the presence of an excessive polymerization inhibitor (hydroquinone),
O-methacryloyl-1,2: 5,6-di-O-isopropylidene-α-D-glucofuranose (DIPGLF
MA) was obtained in a yield of 43%.

3-O-methacryloyl-α-D-glucofuranose and trimethylsilylacetic acid were mixed at a molar ratio of 1: 5 to prepare an anhydrous toluene solution (5 times the volume). Add triethylamine to 1.2 of trimethylsilylacetic acid at room temperature.
A double amount was added, and the mixture was stirred for 2 hours while heating at 100 ° C.
After completion of the reaction, the reaction mixture was washed with a large amount of Na ₂ CO ₃ aqueous solution, the oil layer (toluene layer) was separated, and the aqueous layer was extracted twice with toluene, and the extract was combined with the previous oil layer and saturated brine. The extract was washed, dried with Glauber's salt, and the oil layer was concentrated. This was distilled under reduced pressure in the presence of an excessive polymerization inhibitor (hydroquinone) to give 1,2,5,6-tetratrimethylsilyl-3-methacryloylglucofuranose (TTMSGLFMA).
Was obtained in a yield of 40%.

DIP GLFMA and TTMS prepared previously
GLFMA was mixed at a molar ratio of 1: 4 to obtain a 5 mol / liter toluene solution. To this, 1 mol% of the total molar amount of α, α-azobisisobutyronitrile (AIBN) was added, and the mixture was stirred at 80 ° C. for 8 hours. Then, this solution was poured into a large amount of methanol, and the precipitated polymer was filtered off,
DIP GLFMA-TTMSG which is dried and represented by the following formula
The LFMA polymer was obtained with a yield of 66%. The weight average molecular weight (Mw) of this polymer was 21,000, and the copolymerization ratio m: n =
1: 4. Incidentally, the TMS in the formula represents a trimethylsilyl group _{(-Si (CH 3) 3)} ( hereinafter the same).

[0121]

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Example 2 The polymer obtained in Example 1 was added with 10
% Photo acid generator triphenylsulfonium hexafluoroantimonate (TPSSbF ₆ ) was mixed to obtain a 7% methyl isobutyl ketone (MIBK) solution. This solution was heat-cured with a novolac resist (film thickness 2.0 μm).
m) was spin coated on a precoated silicon wafer and baked at 100 ° C. to a thickness of 0.3 μm. The upper resist film thus formed is exposed using a KrF excimer laser stepper with NA = 0.45, and exposed at 130 ° C. for 1 hour.
Bake for 1 minute, then develop with pure water for 1 minute, 0.40
A μm line and space pattern was formed.
The threshold energy E _th of the irradiation dose at this time is 34 mJ /
cm ² .

Example 3 Using the upper layer resist pattern obtained in Example 2 as a mask, the lower layer resist was etched by oxygen reactive ion etching (O ₂ RIE). The pattern could be transferred to the lower layer of 2.0 μm, and a two-layer positive resist pattern with an aspect ratio of about 5 could be formed.
At this time, the thinning amount of the upper layer was about 300Å, and the selection ratio with the lower layer material was about 67 times.

(Embodiment 4) Instead of pure water used in Embodiment 2, development is carried out for 1 minute with 2.38% tetramethylammonium hydroxide (TMAH), but still 0.25%.
A 40 μm line and space pattern was resolved.

Example 5 In Example 2, the upper layer was not developed with water and both the upper layer and the lower layer were successively patterned by O ₂ RIE.
A space pattern was obtained, and a two-layer positive resist pattern having an aspect ratio of about 5 could be formed.

(Example 6) DIPG obtained in Example 1
LFMA and trimethylsilylmethylmethacrylate (T
MSMMA) was mixed in a molar ratio of 1: 4 to obtain a 5 mol / liter toluene solution. 1 mol% of the total molar amount
AIBN of was added and stirred at 80 ° C. for 8 hours. Then, this solution was poured into a large amount of methanol, and the precipitated polymer was separated by filtration and dried to obtain DIPGLF represented by the following formula.
The MA-TMSMMA polymer was obtained with a yield of 53%. The weight average molecular weight (Mw) of this polymer was 27,000, and the copolymerization ratio was m: n = 1: 4.

[0127]

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Example 7 The polymer obtained in Example 6 was added with 10
% Photoacid generator triphenylsulfonium hexafluoroantimonate was mixed to prepare a 7% MIBK solution.
This solution was spin-coated on a silicon wafer previously coated with a heat-cured novolac resist (film thickness 2.0 μm) and baked at 100 ° C. to a thickness of 0.3 μm.
The upper resist film formed as described above is treated with K having NA = 0.45.
Exposure using rF excimer laser stepper, 13
Bake at 0 ° C for 1 minute, then develop with pure water for 1 minute,
A 0.40 μm line-and-space pattern was formed. The threshold energy E _th of the irradiation dose in this case was 33 mJ / cm ² .

Example 8 Using the upper layer resist pattern obtained in Example 7 as a mask, the lower layer resist was etched by O ₂ RIE. The pattern could be transferred to the lower layer of 2.0 μm, and a two-layer positive resist pattern with an aspect ratio of about 5 could be formed. At this time, the amount of thinning of the upper layer is about 600Å,
The selection ratio with the lower layer material was about 30 times.

(Embodiment 9) A line and space pattern of 0.40 μm was also resolved even when developed with 2.38% TMAH instead of pure water in Embodiment 7 for 1 minute.

(Example 10) 3-O-methacryloyl-
α-D-glucofuranose and t-butyl acetate were mixed at a molar ratio of 1: 5 to prepare an anhydrous toluene solution (5 times amount).
To this solution was added triethylamine in an amount 1.2 times the amount of t-butyl acetate at room temperature, and the mixture was stirred for 2 hours while heating to 100 ° C. After the reaction was completed, the reaction mixture was mixed with a large amount of Na ₂ CO ₃
The mixture was washed with an aqueous solution, the oil layer (toluene layer) was separated, and the aqueous layer was extracted twice with toluene. The extract was combined with the above oil layer, washed with saturated saline, dried with Glauber's salt, and the oil layer was concentrated. This was distilled under reduced pressure in the presence of an excessive polymerization inhibitor (hydroquinone) to give 1,2,5,6-tetra-t-butyl-
3-methacryloyl-α-D-glucofuranose (TT
BUGLFM) was obtained with a yield of 54%.

The TTBUGLFMA thus prepared and the TTMSGLFMA prepared in Example 1 were mixed at a molar ratio of 1: 4 to obtain a 5 mol / liter toluene solution. To this, add 1 mol% of the total molar amount of AIBN and
Stir for hours. Thereafter, this solution was poured into a large amount of methanol, and the precipitated polymer was separated by filtration and dried to obtain a TTBUGLMFMA-TTMSGLFMA polymer represented by the following formula in a yield of 48%. The weight average molecular weight (Mw) of this polymer was 20,000, and the copolymerization ratio was m: n = 1: 4. In addition, t-Bu in the following formula is a t-butyl group (-C
(CH ₃ ) ₃ ) (the same applies hereinafter).

[0133]

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Example 11 The polymer obtained in Example 10 was mixed with 10% of a photo-acid generator triphenylsulfonium hexafluoroantimonate to prepare a 7% MIBK solution. This solution was spin-coated on a silicon wafer previously coated with a heat-cured novolac resist (film thickness 2.0 μm) and baked at 100 ° C. to a thickness of 0.3 μm. The upper resist film thus formed is exposed by using a KrF excimer laser stepper with NA = 0.45, and 1
After baking at 30 ° C. for 1 minute, it was developed with pure water for 1 minute to form a 0.40 μm line-and-space pattern. Threshold energy E _th of irradiation dose at this time
Was 18 mJ / cm ² .

Example 12 Using the upper layer resist pattern obtained in Example 11 as a mask, the lower layer resist was etched by O ₂ RIE. The pattern could be transferred to the lower layer of 2.0 μm, and a two-layer positive resist pattern with an aspect ratio of about 5 could be formed. At this time, the amount of thinning of the upper layer is about 300Å
The selection ratio with the lower layer material was about 67 times.

(Embodiment 13) A line and space pattern of 0.40 μm was also resolved by developing for 1 minute with 2.38% TMAH instead of pure water in Embodiment 11.

(Example 14) When the upper layer in Example 11 was not developed with water and both the upper layer and the lower layer were successively patterned by O ₂ RIE, a line-and-space pattern of 0.50 μm was obtained. 2 with aspect ratio of about 5
A layer positive resist pattern could be formed.

Example 15 DIP prepared in Example 1
GLFMA and bistrimethylsilylmethyl itaconate (TMSMI) were mixed at a molar ratio of 1: 2 to prepare a 5 mol / liter toluene solution. To this, 1 mol% of the total molar amount of AIBN was added, and the mixture was stirred at 80 ° C. for 8 hours. After that, this solution is poured into a large amount of methanol, the precipitated polymer is separated by filtration, dried, and the DIPGL represented by the following formula.
The FMA-TMSMI polymer was obtained with a yield of 40%. The weight average molecular weight (Mw) of this polymer was 15,000, and the copolymerization ratio was m: n = 1: 2.

[0139]

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Example 16 The polymer obtained in Example 15 was mixed with 10% of a photo-acid generator triphenylsulfonium hexafluoroantimonate to prepare a 7% MIBK solution. This solution was spin-coated on a silicon wafer previously coated with a heat-cured novolac resist (film thickness 1.8 μm) and baked at 100 ° C. to a thickness of 0.3 μm. The upper resist film formed in this manner is NA = 0.45.
Exposure using KrF excimer laser stepper,
Bake at 130 ° C for 1 minute, develop with pure water for 1 minute,
A 0.40 μm line-and-space pattern was formed. The threshold energy E _th of the irradiation dose in this case was 14 mJ / cm ² .

Example 17 Using the upper layer resist pattern obtained in Example 16 as a mask, the lower layer resist was etched by O ₂ RIE. The pattern could be transferred to the lower layer of 1.8 μm, and a two-layer positive resist pattern with an aspect ratio of about 5 could be formed. At this time, the amount of thinning of the upper layer is about 500Å
The selection ratio with the lower layer material was about 36 times.

(Embodiment 18) A line-and-space pattern of 0.40 μm was also resolved by developing for 1 minute with 2.38% TMAH instead of pure water in Embodiment 16.

Example 19 DIP prepared in Example 1
GLFMA and bistrimethylsilylmethyl fumarate (TMSMF) were mixed at a molar ratio of 1: 2 to prepare a 5 mol / liter toluene solution. 1 mol of total molar amount in this solution
AIBN of mol% was added and stirred at 80 ° C. for 8 hours.
Then, this solution was poured into a large amount of methanol, the precipitated polymer was filtered off and dried, and DIP represented by the following formula
GLFMA-TMSMF polymer was obtained with a yield of 32%. The weight average molecular weight (Mw) of this polymer was 11,000, and the copolymerization ratio was m: n = 1: 2.

[0144]

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(Example 20) The polymer obtained in Example 19 was mixed with 10% of a photo-acid generator triphenylsulfonium hexafluoroantimonate to prepare a 7% MIBK solution. This solution was spin-coated on a silicon wafer previously coated with a heat-cured novolac resist (film thickness 1.8 μm) and baked at 100 ° C. to a thickness of 0.3 μm. The upper resist film formed in this manner is NA = 0.45.
Exposure using KrF excimer laser stepper,
After baking at 130 ° C. for 1 minute, it was developed with pure water for 1 minute to form a 0.40 μm line-and-space pattern. Threshold energy E of irradiation dose in this case
_th was 13 mJ / cm ² .

Example 21 Using the upper layer resist pattern obtained in Example 20 as a mask, the lower layer resist was etched by O ₂ RIE. The pattern could be transferred to the lower layer of 1.8 μm, and a two-layer positive resist pattern with an aspect ratio of about 5 could be formed. At this time, the amount of thinning of the upper layer is about 500Å
The selection ratio with the lower layer material was about 36 times.

(Embodiment 22) Instead of pure water used in Embodiment 20, development was performed with 2.38% TMAH for 1 minute, and a line and space pattern of 0.40 μm was also resolved.

Example 23 DIP prepared in Example 1
GLFMA and styrene were mixed at a molar ratio of 1: 4 to prepare a 5 mol / liter toluene solution. To this, 1 mol% of the total molar amount of AIBN was added, and the mixture was stirred at 80 ° C. for 8 hours. After that, this solution was put into a large amount of methanol, the precipitated polymer was separated by filtration, and dried to obtain D represented by the following formula.
IPGLFMA-styrene polymer was obtained with a yield of 32%.
The weight average molecular weight (Mw) of this polymer was 26,000,
The copolymerization ratio was m: n = 1: 4.

[0149]

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(Example 24) The polymer obtained in Example 23 was mixed with 10% of a photo-acid generator triphenylsulfonium hexafluoroantimonate to prepare a 12% cyclohexanone solution. This solution was spin-coated on a silicon substrate pretreated with hexamethyldisilazane (HMDS) and baked at 100 ° C. to a thickness of 0.8 μm. The resist film thus formed is exposed using a KrF excimer laser stepper with NA = 0.45, baked at 130 ° C. for 1 minute, and then developed with pure water for 1 minute to give 0.40 μm.
m line and space pattern was formed. The threshold energy E _th of the irradiation dose in this case is 38 mJ /
cm ² .

(Example 25) Even if the film was developed with 2.38% TMAH for 1 minute instead of pure water in Example 24, a line and space pattern of 0.40 µm was also resolved.

Example 26 DIP prepared in Example 1
GLFMA and 1-adamantyl methacrylate 1: 4
Were mixed at a molar ratio of 5 to prepare a 5 mol / liter toluene solution. To this, add 1 mol% of the total molar amount of AIBN,
The mixture was stirred at 80 ° C for 8 hours. Then, this solution was poured into a large amount of methanol, and the precipitated polymer was separated by filtration and dried to obtain a DIPGLMFMA-1-adamantyl methacrylate polymer represented by the following formula in a yield of 58%. The weight average molecular weight (Mw) of this polymer was 15,000, and the copolymerization ratio was m: n = 1: 4.

[0153]

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(Example 27) The polymer obtained in Example 26 was mixed with 10% of a photo-acid generator triphenylsulfonium hexafluoroantimonate to prepare a 12% cyclohexanone solution. This solution was spin coated on a HMDS pretreated silicon substrate and baked at 100 ° C. to 0.8
The thickness was μm. The resist film thus formed has NA = 0.
It was exposed using a 45 KrF excimer laser stepper, baked at 130 ° C. for 1 minute, and then developed with pure water for 1 minute to form a 0.40 μm line-and-space pattern. The threshold energy E _th of the irradiation dose in this case was 43 mJ / cm ² .

(Example 28) Even if the film was developed with 2.38% TMAH for 1 minute instead of pure water in Example 27, a line and space pattern of 0.40 µm was also resolved.

Example 29 Examples 26-28 were repeated except that 2-adamantyl methacrylate was used instead of 1-adamantyl methacrylate in Example 26. The results obtained were similar to these examples. The resin in this case is represented by the following formula.

[0157]

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Example 30 2-Methyl-2-adamantyl methacrylate was used in place of 1-adamantyl methacrylate of Example 26. The same operation as in Example 27 was performed with similar results. The threshold energy E _th of the irradiation dose in this case was 12 mJ / cm ² . The resin in this case is represented by the following formula.

[0159]

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Example 31 TT prepared in Example 10
BUGLFMA and 1-adamantyl methacrylate were mixed at a molar ratio of 1: 4 to obtain a 5 mol / liter toluene solution. To this, 1 mol% of the total molar amount of AIBN was added, and the mixture was stirred at 80 ° C. for 8 hours. Then, this solution was poured into a large amount of methanol, the precipitated polymer was separated by filtration and dried, and TBUDIPGLFMA- represented by the following formula.
A 1-adamantyl methacrylate polymer was obtained with a yield of 55%. The weight average molecular weight (Mw) of this polymer was 12,0.
00 and the copolymerization ratio m: n = 1: 4.

[0161]

[Chemical formula 61]

(Example 32) The polymer obtained in Example 31 was mixed with 10% of a photo-acid generator triphenylsulfonium hexafluoroantimonate to prepare a 12% cyclohexanone solution. This solution was spin coated on a HMDS pretreated silicon substrate and baked at 100 ° C. to 0.8
The thickness was μm. The resist film thus formed has NA = 0.
It was exposed using a 45 KrF excimer laser stepper, baked at 130 ° C. for 1 minute, and then developed with pure water for 1 minute to form a 0.40 μm line-and-space pattern. The threshold energy E _th of the irradiation dose in this case was 36 mJ / cm ² .

(Example 33) Even if the film was developed with 2.38% TMAH for 1 minute instead of pure water in Example 32, a line and space pattern of 0.40 µm was also resolved.

(Example 34) The following formula

[0165]

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A polymer having a composition ratio of t-butyl vinyl ether and styrene (m: n ratio in the formula) of about 3: 2 and a weight average molecular weight of 8,000 and represented by the formula: triphenylsulfonium which is a photoacid generator. Hexafluoroantimonate (TPSSbF ₆ ) was added at 10% by weight of the polymer to obtain a 7% by weight cyclohexanone solution. This solution was spin-coated on a silicon wafer and prebaked at 100 ° C. for 100 seconds to form a resist film having a thickness of 0.7 μm. This was exposed with a KrF excimer laser (NA = 0.45), and 1 minute after the exposure, it was baked at 100 ° C. for 60 seconds. Next, when the resist film was developed with pure water for 1 minute, it was 0.40.
The line and space pattern of μm could be resolved. Irradiation dose threshold energy E _th = 68 mJ / cm
^{Was 2} .

(Example 35) The resist film exposed and baked in Example 34 was replaced with 2.38% TMA instead of pure water.
Even if developed with H for 1 minute, the line of 0.40 μm
Resolved the And Space pattern.

(Example 36) The following formula

[0169]

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(In the formula, t-Am is a t-amyl group (-
The composition ratio of t-amyl vinyl ether and styrene (m: n ratio in the formula) represented by C (CH ₃ ) ₂ -C ₂ H ₅ ) (the same applies below) is about 3: 2, and the weight average is A photo acid generator TPSSbF ₆ is added to a polymer having a molecular weight of 8,500.
10% by weight of the polymer was added to obtain a 7% by weight cyclohexanone solution. This solution was spin-coated on a silicon wafer and pre-baked to form a resist film having a thickness of 0.7 μm. This is a KrF excimer laser (NA =
0.45), and 1 minute after the exposure, baking was performed at 100 ° C. for 60 seconds. Next, when the resist film was developed with pure water for 1 minute, a line and space pattern of 0.4 μm could be resolved. Irradiation dose threshold energy E _th = 7
It was 8 mJ / cm ² .

(Example 37) The resist film exposed and baked in Example 36 was replaced with 2.38% TMA instead of pure water.
Even after development with H for 1 minute, a line and space pattern of 0.4 μm was resolved.

(Example 38) The following formula

[0173]

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The compositional ratio (m: n ratio in the formula) of t-butyl vinyl ether and α-methylstyrene represented by: about 3:
2. To a polymer having a weight average molecular weight of 6,000, add 5% by weight of TPSSbF ₆ , which is a photoacid generator, to the polymer.
A 5 wt% cyclohexanone solution was prepared. This solution is spin-coated on a silicon wafer, pre-baked,
The resist film was 0.3 μm thick. This was exposed with a KrF excimer laser (NA = 0.45), and 1 minute after the exposure, it was baked at 100 ° C. for 60 seconds. Next, when the resist film was developed with pure water for 1 minute, a line and space pattern of 0.4 μm could be resolved. It was a threshold energy E _th = 68mJ / cm ² of irradiation dose.

(Example 39) The resist film exposed and baked in Example 38 was replaced with 2.38% TMA instead of pure water.
Even after development with H for 1 minute, a line and space pattern of 0.4 μm was resolved.

(Example 40) The following formula

[0177]

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The compositional ratio (m: n ratio in the formula) of t-amyl vinyl ether and α-methylstyrene represented by: about 3:
2. To a polymer having a weight average molecular weight of 5,000, 5% by weight of the polymer, TPSSbF ₆ , which is a photoacid generator, is added.
A 5 wt% cyclohexanone solution was prepared. This solution is spin-coated on a silicon wafer, pre-baked,
The resist film was 0.3 μm thick. This was exposed with a KrF excimer laser (NA = 0.45), and 1 minute after the exposure, it was baked at 100 ° C. for 60 seconds. When this resist film was developed with pure water for 1 minute, a line and space pattern of 0.4 μm could be resolved. It was a threshold energy E _th = 78mJ / cm ² of irradiation dose.

(Example 41) The resist film which was exposed and baked in Example 40 was replaced with 2.38% TMA instead of pure water.
Even after development with H for 1 minute, a line and space pattern of 0.4 μm was resolved.

(Example 42) The following formula

[0181]

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The composition of t-butyl vinyl ether and allyltrimethylsilane represented by the formula (m: n ratio in the formula) of about 3: 2 and the weight average molecular weight of 10,000 was added to a polymer of TPSSbF which is a photoacid generator. ₆ to 10% by weight of polymer
In addition, a 7 wt% cyclohexanone solution was prepared. This solution was spin-coated on a silicon wafer and pre-baked to form a resist film having a thickness of 0.3 μm. This is called KrF
It was exposed with an excimer laser (NA = 0.45), and after 1 minute of exposure, baked at 100 ° C. for 60 seconds. When this resist film was developed with pure water for 1 minute, a line and space pattern of 0.4 μm could be resolved. It was a threshold energy E _th = 64mJ / cm ² of irradiation dose.

(Example 43) The resist film which was exposed and baked in Example 42 was replaced with 2.38% TMA instead of pure water.
When developed with H for 1 minute, a 0.4 μm line-and-space pattern was resolved.

Example 44 A novolac resin resist was applied on a silicon substrate and baked at 200 ° C. for 180 seconds to form a resist film having a thickness of 1.2 μm. Then, according to the procedure of Example 41, t-
A resist pattern of butyl vinyl ether-allyl trimethylsilane polymer was formed, and this pattern was used as a mask for O ₂ RI of the underlying novolac resin resist.
E treatment was performed. The upper layer pattern was transferred to the lower layer resist, and a two-layer resist pattern could be formed with a line and space of 0.4 μm.

(Example 45) The following formula

[0186]

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The composition of trimethylsilyl vinyl ether and fumaronitrile represented by the formula (m: n ratio in the formula) of about 1: 1 and the weight average molecular weight of 3,500 was added to a polymer of TPSSbF ₆ which is a photo-acid generator. 15 wt% was added to give a 10 wt% cyclohexanone solution. This solution was spin-coated on a silicon wafer and pre-baked to form a resist film having a thickness of 0.7 μm. This is called KrF
It was exposed with an excimer laser (NA = 0.45), and after 1 minute of exposure, baked at 100 ° C. for 60 seconds. When this resist film was developed with pure water for 1 minute, a line and space pattern of 0.4 μm could be resolved. The threshold energy E _th of the irradiation dose was 82 mJ / cm ² .

(Example 46) The resist film which was exposed and baked in Example 45 was dry-developed with oxygen plasma instead of pure water.
I was able to resolve the space pattern. The plasma condition at this time is 30 with a parallel plate type reactive ion plasma etcher.
It was 0 W, O ₂ flow rate was 200 sccm, and 3 mTorr for 5 minutes (same in the following examples).

Example 47 A novolak resin resist was applied on a silicon substrate and baked at 200 ° C. for 180 seconds to form a resist film having a thickness of 1.2 μm. On top of this, follow the procedure of Example 45 or 46 to obtain a film thickness of 3,000.
A resist pattern of trimethylsilyl vinyl ether-fumaronitrile polymer is formed with Å, and this pattern is used as a mask for O of the lower novolak resin resist.
₂ RIE processing was performed. In either case of using the procedure of Example 45 or 46, the upper layer pattern was transferred to the lower layer resist, and the double layer resist pattern could be formed with a line and space of 0.4 μm.

(Example 48) The following formula

[0191]

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T-butyl vinyl ether represented by
Composition ratio of trimethylsilyl vinyl ether (m in the formula:
n ratio) about 1: 1, a polymer having a weight average molecular weight of 8,000
And photo-acid generator TPSSbF₆5% by weight of polymer
In addition, a 15 wt% cyclohexanone solution was prepared. this
The solution is spin-coated on a silicon wafer and pre-baked.
To give a resist film having a thickness of 0.3 μm. This is Kr
Exposure with F excimer laser (NA = 0.45)
After 1 minute of light, it was baked at 100 ° C. for 60 seconds. This Regis
The developed film was developed with pure water for 1 minute.
I was able to resolve the pattern and space. Irradiation dose
Threshold energy E_thIs 30 mJ / cm ²Met.

(Example 49) The resist film which was exposed and baked in Example 48 was dry-developed with oxygen plasma instead of pure water.
I was able to resolve the space pattern.

Example 50 A novolak resin resist was applied on a silicon substrate and baked at 200 ° C. for 180 seconds to form a resist film having a thickness of 1.2 μm. On top of this, follow the procedure of Example 48 or 49 to obtain a film thickness of 3,000.
A resist pattern of t-butyl vinyl ether-trimethylsilyl vinyl ether polymer was formed with Å, and the novolak resin resist of the lower layer was subjected to O ₂ RIE treatment using this pattern as a mask. Example 48 or 49
No matter which procedure is used, the upper layer pattern is transferred to the lower layer resist and the line and
A two-layer resist pattern could be formed in the space.

(Example 51) The following formula

[0196]

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The compositional ratio of trimethylsilyl vinyl ether and fumaric anhydride represented by the formula (m: n ratio in the formula) is about 7:
3. To a polymer having a weight average molecular weight of 8,300, 5% by weight of the polymer, TPSSbF ₆ , which is a photoacid generator, was added.
The solution was a cyclohexanone solution of wt%. This solution is spin-coated on a silicon wafer, pre-baked,
The resist film was 0.3 μm thick. This was exposed with a KrF excimer laser (NA = 0.45), and 1 minute after the exposure, it was baked at 100 ° C. for 60 seconds. When this resist film was developed with pure water for 1 minute, a line and space pattern of 0.4 μm could be resolved. The threshold energy E _th of the irradiation dose was 28 mJ / cm ² .

(Example 52) The resist film which was exposed and baked in Example 51 was dry-developed with oxygen plasma instead of pure water.
I was able to resolve the space pattern.

Example 53 A novolak resin resist was applied on a silicon substrate and baked at 200 ° C. for 180 seconds to form a resist film having a thickness of 1.2 μm. On top of this, follow the procedure of Example 51 or 52 to obtain a film thickness of 3,000.
A resist pattern of trimethylsilyl vinyl ether-fumaric anhydride polymer is formed with Å, and this pattern is used as a mask for O _{2 of the} lower novolak resin resist.
RIE processing was performed. Using either procedure of Example 51 or 52, the upper layer pattern is transferred to the lower layer resist and the line and space of 0.4 μm
A layer resist pattern could be formed.

(Example 54) The following formula

[0201]

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The composition ratio of trimethylsilyl vinyl ether and maleimide represented by the formula (m: n ratio in the formula) is about 7:
3. To a polymer having a weight average molecular weight of 7,000, TPSSbF ₆ which is a photoacid generator is added in an amount of 5% by weight of the polymer, and 5
The solution was a cyclohexanone solution of wt%. This solution is spin-coated on a silicon wafer, pre-baked,
The resist film was 0.3 μm thick. This was exposed with a KrF excimer laser (NA = 0.45), and 1 minute after the exposure, it was baked at 100 ° C. for 60 seconds. When this resist film was developed with pure water for 1 minute, a line and space pattern of 0.4 μm could be resolved. It was a threshold energy E _th = 24mJ / cm ² of irradiation dose.

(Example 55) The resist film which was exposed and baked in Example 54 was dry-developed with oxygen plasma instead of pure water.
I was able to resolve the space pattern.

Example 56 A novolak resin resist was applied on a silicon substrate and baked at 200 ° C. for 180 seconds to form a resist film having a thickness of 1.2 μm. On top of this, follow the procedure of Example 54 or 55 to obtain a film thickness of 3,000.
A resist pattern of trimethylsilyl vinyl ether-maleimide polymer is formed with Å, and this pattern is used as a mask for O ₂ R of the lower novolak resin resist.
IE treatment was performed. Regardless of which of the procedures of Examples 54 and 55 was used, the upper layer pattern was transferred to the lower layer resist, and a two-layer resist pattern could be formed with a line and space of 0.4 μm.

(Example 57) The following formula

[0206]

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Trimethylsilyl vinyl ether represented by
The composition ratio of ter and t-butylmaleimide (m: n in the formula)
Ratio) about 1: 1, a polymer having a weight average molecular weight of 4,500
In addition, TPSSbF which is a photo-acid generator₆5 layers of polymer
% Cyclohexanone solution was added.
This solution is spin-coated on a silicon wafer and
The resist film was baked to form a resist film having a thickness of 0.3 μm. this
Exposure with KrF excimer laser (NA = 0.45)
Then, after 1 minute of exposure, baking was performed at 100 ° C. for 60 seconds. this
When the resist film was developed with pure water for 1 minute, 0.4 μm
I was able to resolve the line and space pattern. Teru
Radiation threshold energy E_th= 18 mJ / cm ²In
Was.

(Example 58) The resist film which was exposed and baked in Example 57 was dry-developed with oxygen plasma instead of pure water.
I was able to resolve the space pattern.

Example 59 A novolac resin resist was applied on a silicon substrate and baked at 200 ° C. for 180 seconds to form a resist film having a thickness of 1.2 μm. On top of this, follow the procedure of Example 57 or 58 to obtain a film thickness of 3,000.
A resist pattern of trimethylsilyl vinyl ether-t-butylmaleimide polymer was formed with Å, and the underlayer novolak resin resist was subjected to O ₂ RIE treatment using this pattern as a mask. Example 57 or 58
No matter which procedure is used, the upper layer pattern is transferred to the lower layer resist and the line and
A two-layer resist pattern could be formed in the space.

(Example 60) The following formula

[0211]

Embedded image

The compositional ratio (m: n ratio in the formula) of trimethylsilyl vinyl ether and dimethyl t-butylsilylmaleimide represented by the formula: about 1: 1, weight average molecular weight 10,0.
5% by weight of the photoacid generator TPSSbF ₆ was added to the polymer No. 00 to prepare a 15% by weight cyclohexanone solution. This solution was spin-coated on a silicon wafer and pre-baked to form a resist film having a thickness of 0.3 μm. This is a KrF excimer laser (NA = 0.4
5), and 1 minute after the exposure, baking was performed at 100 ° C. for 60 seconds. When this resist film was developed with pure water for 1 minute,
A line and space pattern of 0.4 μm could be resolved. Irradiation dose threshold energy E _th = 20 mJ /
cm ² .

(Example 61) The resist film which was exposed and baked in Example 60 was dry-developed with oxygen plasma instead of pure water.
I was able to resolve the space pattern.

Example 62 A novolak resin resist was applied on a silicon substrate and baked at 200 ° C. for 180 seconds to form a resist film having a thickness of 1.8 μm. Then, according to the procedure of Example 60 or 61, a film thickness of 3,000 is obtained.
A resist pattern of trimethylsilyl vinyl ether-dimethyl t-butylsilylmaleimide polymer was formed with Å, and the lower layer novolak resin resist was subjected to O ₂ RIE treatment using this pattern as a mask. Whichever the procedure of Example 60 or 61 was used, the upper layer pattern was transferred to the lower layer resist, and the double layer resist pattern could be formed with a line and space of 0.4 μm.

(Example 63) The following formula

[0216]

Embedded image

The compositional ratio (m: n ratio in the formula) of trimethylsilyl vinyl ether and dimethylisoprolylsilylmaleimide represented by the formula: about 1: 1, weight average molecular weight 8,000.
To the polymer of No. 0, TPSSbF ₆ as a photo-acid generator was added in an amount of 5% by weight of the polymer to prepare a 15% by weight cyclohexanone solution. This solution was spin-coated on a silicon wafer and pre-baked to form a resist film having a thickness of 0.3 μm. This is a KrF excimer laser (NA = 0.4
5), and 1 minute after the exposure, baking was performed at 100 ° C. for 60 seconds. When this resist film was developed with pure water for 1 minute,
A line and space pattern of 0.4 μm could be resolved. The irradiation energy threshold energy E _th is 18 mJ /
cm ² .

(Example 64) The resist film which was exposed and baked in Example 63 was dry-developed with oxygen plasma instead of pure water.
I was able to resolve the space pattern.

Example 65 A novolac resin resist was applied on a silicon substrate and baked at 200 ° C. for 180 seconds to form a resist film having a thickness of 1.8 μm. Then, according to the procedure of Example 63 or 64, a film thickness of 3,000 is obtained.
A resist pattern of trimethylsilyl vinyl ether-dimethylisoprolylsilylmaleimide polymer was formed with Å and the lower layer novolak resin resist was subjected to O ₂ RIE treatment using this pattern as a mask. Regardless of which procedure of Examples 63 or 64 was used, the upper layer pattern was transferred to the lower layer resist, and a two-layer resist pattern could be formed with a line and space of 0.4 μm.

As can be seen from these examples, the resolution when developing a resist film formed from the resist composition of the present invention with water is 0.30 to 0.40 so far.
It is about μm line and space, which is not as high as the highest resolution of conventional chemically amplified resists, but is sufficient for practical use.

[0221]

As described above, by using the resist composition of the present invention, a resist pattern can be formed using water that is harmless to the human body. The property of the resist composition of the present invention that it is developable with water is an epoch-making property not found in various resist materials hitherto, that is, according to the present invention, such as an organic solvent or an organic alkaline aqueous solution. The resist pattern can be safely developed in a work environment without using a special developer. Therefore, the present invention can greatly contribute to the improvement of safety in semiconductor device manufacturing. Furthermore, if the resist composition of the present invention is used, development equipment can be simplified,
Moreover, maintenance work of the device can be easily performed.

Claims (27)

[Claims] 1. A resist composition comprising a main resin and a photo-acid generator, wherein a polymer constituting the main resin contains a repeating unit having a protected hydroxyl group. 2. The hydroxyl group-protected repeating unit is represented by the following formula: 1.
The resist composition as described in the above. Embedded image (R ^{1 in} this formula is hydrogen, an alkyl group having 1 to 6 carbon atoms, a halogen, or a halogenated alkyl group,
Is a group derived from glucofuranose having a protected hydroxyl group, represented by the following formula: (R ^{2 to} R ^{5 in} this formula are an alkyl group having 1 to 6 carbon atoms or a halogenated alkyl group, which may be the same or different, and R ^{6 to} R ⁹ are each an acid. Groups which are leaving groups, which may be the same or different, and n is 0 or an integer of 1 or more). 3. The resist composition according to claim 2, wherein the polymer is a homopolymer. 4. The resist composition according to claim 2, wherein the polymer is a copolymer. 5. The resist composition according to claim 4, wherein the copolymer has a structure represented by the following formula. Embedded image (R ¹ and X in this formula are as defined above, R ¹⁰ has the same definition as R ¹ , R ¹⁰ and R ¹ may be the same or different, and R ¹¹ to R ¹⁴ has 1 carbon atom
~ 6 and containing at least one silicon atom, k and m are positive integers, n is as defined above, and p is an integer of 0 or 1 or greater. is there) 6. The resist composition according to claim 5, wherein R ^{11 to} R ¹⁴ are substituted silyl groups. 7. The resist composition according to claim 4, wherein the copolymer has a structure represented by the following formula. Embedded image (R ¹ and X in this formula are as defined above, R ¹⁰ has the same definition as R ¹ , R ¹⁰ and R ¹ may be the same or different, and R ¹¹ is A group having 1 to 6 carbon atoms and containing at least one silicon atom, k and m are positive integers, n is as defined above, and p is 0 or 1. Is an integer greater than or equal to) 8. The resist composition according to claim 4, wherein the copolymer has a structure represented by the following formula. Embedded image (R ¹ and X in this formula are as defined above, R ¹¹ and R ¹² are groups having 1 to 6 carbon atoms and containing at least one silicon atom, and k and m Is a positive integer, n is as defined above, and p and q are 0 or an integer greater than or equal to 1) 9. The resist composition according to claim 4, wherein the copolymer has a structure represented by the following formula. [Chemical 6] (R ¹ and X in this formula are as defined above, R ¹¹ and R ¹² are groups having 1 to 6 carbon atoms and containing at least one silicon atom, and k and m Is a positive integer, n is as defined above, and p is an integer greater than or equal to 0) 10. The resist composition according to claim 4, wherein the copolymer has a structure represented by the following formula. [Chemical 7] (R ¹ and X in this formula are as defined above, R ¹⁵ is a substituent obtained from an alicyclic hydrocarbon or a derivative thereof, k and m are positive integers, and n is Is as defined above) 11. The resist composition according to claim 4, wherein the copolymer has a structure represented by the following formula. Embedded image (R ¹ and X in this formula are as defined above, and R ¹⁵ and R ¹⁶ are substituents derived from an alicyclic hydrocarbon or a derivative thereof, and these may be the same. May be different, k and m are positive integers, and n is as defined above). 12. The resist composition according to claim 4, wherein the copolymer has a structure represented by the following formula. Embedded image (R ¹ and X in this formula are as defined above, and R ¹⁵ and R ¹⁶ are substituents derived from an alicyclic hydrocarbon or a derivative thereof, and these may be the same. May be different, k and m are positive integers, and n is as defined above). 13. The resist composition according to claim 4, wherein the copolymer has a structure represented by the following formula. Embedded image (R ¹ and X in this formula are as defined above, R ¹⁰ has the same definition as R ¹ , R ¹⁰ and R ¹ may be the same or different, and R ¹⁷ is Substituents derived from aromatic hydrocarbons or their derivatives, k and m are positive integers, and n is as defined above). 14. The polymer constituting the main resin is represented by the following formula as one of repeating units: 2. A copolymer containing a repeating unit derived from vinyl alcohol protected with a hydroxyl group, represented by the formula (R ^{I in} this formula is a group capable of leaving by an acid). Resist composition. 15. The resist composition according to claim 14, wherein the copolymer has a structure represented by the following formula. [Chemical 12] (R ^{I in} this formula is as defined above, and R
^II is hydrogen, an alkyl group having 1 to 12 carbon atoms, halogen,
Or a halogenated alkyl group, R ^{III to} R ^VII are hydrogen, an alkyl group having 1 to 12 carbon atoms, a halogen, a halogenated alkyl group, or a group having 1 to 9 carbon atoms and containing silicon, (m and n are positive integers) 16. The resist composition according to claim 14, wherein the copolymer has a structure represented by the following formula. Embedded image (R ^{I in} this formula is as previously defined, and R ^VIII
Is a group having 1 to 9 carbon atoms and containing at least one silicon atom, and m and n are positive integers). 17. The resist composition according to claim 14, wherein the copolymer has a structure represented by the following formula. Embedded image (R ^{I in} this formula is as defined above, R ^IX is a substituted silyl group having 1 to 9 carbon atoms, and m and n are positive integers.) 18. The resist composition according to claim 14, wherein the copolymer has a structure represented by the following formula. Embedded image (Wherein R ^I is as defined above, R ^X is hydrogen, R ^I , a group having 1 to 9 carbon atoms and containing at least one silicon atom, or a group having 1 to 9 carbon atoms. It is a substituted silyl group, and m and n are positive integers.) 19. The resist composition according to claim 14, wherein the copolymer has a structure represented by the following formula. Embedded image (R ^{I in} this equation is as defined above, m, n
Is a positive integer) 20. The resist composition according to claim 14, wherein the copolymer has a structure represented by the following formula. Embedded image (R ^{I in} this equation is as defined above, m, n
Is a positive integer) 21. The resist composition according to claim 19, wherein the R ^I is a trimethylsilyl group. 22. A solution of the resist composition according to any one of claims 1 to 22 is applied on a substrate to be treated, and the resist film formed is pre-baked, and then the resist film is selectively exposed to radiation. A method for forming a resist pattern, which comprises exposing to form a latent image of a desired pattern, baking the resist film after exposure, and developing the latent image. 23. The method according to claim 22, wherein the developing is performed using water as a developing solution. 24. The method according to claim 22, wherein the developing is performed using a mixed solution of water and an alcohol having 1 to 5 carbon atoms as a developing solution. 25. The method according to claim 22, wherein the developing is performed by using an aqueous alkaline solution as a developing solution. 26. The method according to claim 22, wherein the development is carried out using a mixture of an aqueous alkaline solution and an alcohol having 1 to 5 carbon atoms as a developing solution. 27. The base resin of the resist composition has a substituent containing a silicon atom, and the substituent is bonded to oxygen through the silicon atom, and the development is performed using oxygen plasma. Characterized by performing in the gas phase,
27. A method according to any one of claims 22 to 26.