JP3431481B2 - Photosensitive composition, pattern forming method using the same, and method for manufacturing electronic component - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive composition suitable as a resist used for semiconductor devices, particularly thin-film magnetic heads such as large-scale integrated circuits (LSI), hard disk drives, and liquid crystal displays. And a pattern forming method using the same and an electronic component manufacturing method.

[0002]

2. Description of the Related Art In the field of electronic parts such as semiconductor integrated circuit devices such as LSIs, thin film magnetic heads such as hard disk drives, and various fine processings such as liquid crystal displays, photolithography technology using a resist is used. A fine pattern is formed. Particularly in recent years, it has been required to form a finer resist pattern with the diversification, multi-functionality and high density of electronic devices. One measure for forming a fine resist pattern is to shorten the wavelength of the exposure light source,
Recently, a resist pattern forming technique using short-wavelength light such as ArF excimer laser (193 nm) or YAG laser fifth harmonic (213 nm) as an exposure light source has been developed.

However, since a normal resist material transmits light in this wavelength region only for about 1/30 micron, the exposure light reaches the portion away from the surface of the resist film at the time of exposure, that is, the portion of the resist film on the substrate side. Can't reach enough. As a result, with such a resist material, there is a problem that it is difficult to form a fine pattern even with exposure light having a short wavelength.

In order to fully exert the effect of shortening the wavelength of exposure light to form a fine pattern, a resist having high transparency to light of that wavelength is indispensable. Further, in order to more effectively perform fine processing of the wiring pattern by using the obtained resist pattern as an etching mask, the resist is required to have sufficient dry etching resistance.

Therefore, as a resist material having excellent light transparency, Japanese Patent Application Laid-Open No. 4-39665 discloses a copolymer of a monomer having an aliphatic hydrocarbon as a skeleton and an alkali-soluble monomer. A resist containing is disclosed. Although this resist has excellent light transparency and sufficient dry etching resistance, it has a problem in solubility in a developing solution. The copolymer contained in this resist is obtained by copolymerizing two monomers having extreme physical properties, that is, an alicyclic compound that does not exhibit alkali solubility at all and a carboxylic acid compound that strongly exhibits alkali solubility. It is a polymer. Therefore, when a resist pattern is formed using such a resist, it is inevitable that only the alkali-soluble portion is dissolved during development, resulting in non-uniform dissolution. As a result, it was difficult to obtain sufficient resolution, cracks and surface roughness easily occurred due to partial dissolution in the unexposed portion of the resist film, and reproducibility of pattern formation was low. Further, the developer penetrates into the interface between the resist film and the substrate, and in the worst case, the pattern collapses. In addition, since such a copolymer easily causes phase separation and is not uniformly dissolved in a solvent, there is a big problem in selection of a coating solvent and coatability on a substrate.

[0006] Japanese Patent Application No. 5-4953 discloses a resist containing a conjugated aromatic compound. Such a resist has excellent dry etching resistance, and its alkali solubility, solvent solubility and substrate adhesion are similar to those of conventional phenol resins. However, the transparency for short-wavelength light as described above is inferior to that of the former, and therefore a pattern cannot be formed with high accuracy.

As described above, it has high transparency to short-wavelength light such as ArF excimer laser and F ₂ excimer laser and has excellent alkali solubility, and
Although development of a resist material having good resolution and reproducibility and having sufficient dry etching resistance for fine processing is desired, a resist material satisfying these conditions has not yet been obtained. Absent.

In order to obtain sufficient dry etching resistance, it is preferable that the alicyclic compound is polycyclic, and therefore, bulky one tends to be selected as the substituent of the acrylic ester.

However, when a bulky alicyclic compound is selected as a substituent for improving dry etching resistance, the following problems occur. That is, the acidic group such as a carboxyl group that imparts alkali solubility to the polymer constitutes the main chain together with the alicyclic compound as the same acrylic unit of the polymer copolymer. Therefore, the distance of the acidic group from the main chain is usually shorter than that of the bulky ester group. In the higher-order structure of the copolymer, it is unavoidable that it is affected by the steric hindrance of the highly hydrophobic alicyclic substituent. That is, the approach of the developing solution to the acidic groups of alkali molecules and the interaction between the resist film and the substrate surface are prevented. Therefore, it becomes difficult to obtain an appropriate dissolution property of the resist film in the developer,
It was not possible to obtain sufficient adhesion between the resist film and the substrate.

As a result, it was difficult to obtain sufficient resolution, cracks and surface roughness easily occurred due to partial dissolution in the unexposed portion of the resist film, and the reproducibility of pattern formation was low. Moreover, since the adhesiveness between the obtained resist pattern and the substrate is not sufficient, the developer penetrates into the interface between the pattern and the substrate, and in the worst case, the pattern collapses.

It has a sufficiently high dry etching resistance,
And as the resist capable of alkali development, for example,
A chemically amplified resist as disclosed in JP-A-63-27829 can be used. This chemically amplified resist is a composition containing an alkali-soluble resin, a dissolution inhibitor, and a compound (photoacid generator) that generates an acid upon irradiation with actinic radiation, and is a dissolution inhibitor in an unexposed state. As a result, the solubility in the alkaline developer is suppressed.
On the other hand, on the resist film formed on the substrate, ultraviolet rays, X-rays,
Alternatively, when irradiated with a high-energy electron beam, the photo-acid generator is decomposed to generate an acid, and when the baking treatment is further applied, the acid acts as a catalyst to decompose the dissolution inhibitor. As a result, the exposed portion of the resist film selectively exhibits alkali solubility and dissolves in the developing solution to form a pattern, and the resist is a positive type resist.

In such a chemically amplified resist, the trace amount of acid generated by short-time exposure is used as a catalyst to enhance the alkali solubility of only the exposed portion of the resist film by baking in the subsequent step, resulting in a difference in solubility from the unexposed portion. Excuse me. Therefore, the resist pattern formation using the chemically amplified resist has an advantage that the exposure light can be reduced and the sensitivity can be easily increased. But on the other hand,
Due to the demand for high density and high productivity of devices, it is necessary to further increase the sensitivity of resists.

In a chemically amplified resist, it is possible to achieve high sensitivity by baking at a high temperature in a post process after exposure to promote a thermal reaction, but baking for a long time generally lowers the pattern profile. Will be accompanied. It is also an effective method to increase the amount of acid generated by exposure by adding a large amount of a photo-acid generator that serves as a catalyst for thermal reaction. However, in this case, the transmittance at the exposure wavelength is lowered, which may also lead to the deterioration of the pattern profile. For electron beam resists regardless of transparency, it is advantageous to improve sensitivity by such a method, but on the other hand, shortening drawing time by increasing device density is a greater problem than photolithography. Is desired.

[0014]

As described above, in addition to having alkali solubility and high dry etching resistance,
As a resist that can achieve high sensitivity, there is a demand for measures that can improve the sensitivity more than the chemical amplification type. In particular, for 1 Gbit DRAM devices, production by direct electron beam writing is under consideration, and high sensitivity is indispensable, but a high sensitivity measure more than the chemical amplification type effect was required.

Therefore, the present invention has a high optical transparency to deep ultraviolet rays having a short wavelength, has an excellent alkali solubility, and also has good adhesion to a substrate and dry etching resistance, and thus is used as a resist material. It is an object to provide a suitable photosensitive composition.

[0016]

[0017]

It is another object of the present invention to provide a pattern forming method using the above-mentioned photosensitive composition and a method for manufacturing an electronic component.

[0019]

In order to solve the above problems, the present invention provides a high molecular polymer having a repeating unit represented by the following general formula (1A) and a compound which generates an acid upon irradiation with actinic radiation. A photosensitive composition containing and is provided.

[0020]

[Chemical 8] (In the general formula (1A), R ¹¹ represents a hydrogen atom or methyl.
A group, a halogen atom or a cyano group, R ¹² is methyl.
And R ¹³ is a) a linear aliphatic group having 2 to 12 carbon atoms; a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, and a bridging hydrocarbon introduced therein. Cyclic group selected from the group consisting of a steroid, a spiro ring, a terpene ring, a steroid, a tanjusan, a digitalloid ring, a camphor ring, an isocamphor ring, a sesquiterpene ring, a sandton ring, a diterpene ring, a triterpene ring, and a steroid saponin. ; and _{b) - (CH 2) m} - (m is one of the hydrocarbon groups represented by 3 to 9 which is an integer). R ¹⁴ is a hydrophilic group. )

The present invention further provides a high molecular polymer containing a repeating unit represented by the following general formula (2) and at least one repeating unit represented by the following general formula (3), and an acid upon irradiation with actinic radiation. A photosensitive composition containing a compound that generates

[0022]

[Chemical 9] (In the general formula (2), R ²¹ represents a hydrogen atom, a methyl group,
It is a halogen atom or a cyano group, and R ²² is a methyl group . R ²³ , R ²⁴ , R ²⁵ and R ²⁶ may be the same or different and each is a hydrogen atom or a hydrocarbon group having 6 or less carbon atoms. )

[0023]

[Chemical 10] (In the general formula (3), R ³¹ represents a hydrogen atom, a methyl group,
It is a halogen atom or a cyano group, and R ³² is a methyl group . At least one of R ³³ , R ³⁴ , R ³⁵ , R ^36, and R ³⁷ is a hydrocarbon group having 6 or less carbon atoms, and the rest may be the same or different, and a hydrogen atom, a methyl group, a halogen atom, And a cyano group. ) Furthermore, the present invention provides a photosensitive composition containing a high molecular polymer having a repeating unit represented by the following general formula (4) and a compound capable of generating an acid upon irradiation with actinic radiation.

[0024]

[Chemical 11] (In the general formula (4), R ⁴¹ represents a hydrogen atom, a methyl group,
A halogen atom or a cyano group, R ⁴⁴ is a cyclobutane ring, a cyclooctane ring, those bridged hydrocarbon is introduced to, spirocyclic, terpenes ring, steroids,
It is a cyclic group selected from the group consisting of tanjusan, digitalloid ring, camphor ring, isocamphor ring, sesquiterpene ring, sandton ring, diterpene ring, triterpene ring, and steroid saponins, and R ⁴⁵ is a hydrophilic group. )

[0025]

[0026]

[0027]

Further, the present invention comprises the steps of applying a photosensitive composition of any of the above to a substrate to form a resist film, and irradiating a predetermined region of the resist film with light to perform pattern exposure. And a step of developing the resist film after the pattern exposure with an image liquid to form a resist pattern, and a step of patterning a substrate using the resist pattern as an etching mask. To do.

The present invention will be described in detail below.

The photosensitive composition of the first invention comprises a high molecular polymer having a repeating unit represented by the above general formula (1A), (1B) or general formula (4).

[0031]

R ¹³ in the general formulas (1A) and (1B) may have a branch in its structure, and may further contain an oxygen atom or a nitrogen atom in the ring. However, considering the stability of the cyclic portion, R ¹³ is most preferably a 6-membered ring or a 5-membered ring having a small intra-ring strain, or a combination thereof.

Examples of the hydrophilic group which can be introduced as R ¹⁴ in the general formula (1A) include a hydroxyl group and a carboxyl group.

Examples of the repeating unit represented by the general formula (1B) include those represented by the following general formula (2) or general formula (3).

[0035]

[Chemical 12] (In the general formula (2), R ²¹ represents a hydrogen atom, a methyl group,
It is a halogen atom or a cyano group, and R ²² is a methyl group . R ²³ , R ²⁴ , R ²⁵ and R ²⁶ may be the same or different and each is a hydrogen atom or a hydrocarbon group having 6 or less carbon atoms. )

[0036]

[Chemical 13] (In the general formula (3), R ³¹ represents a hydrogen atom, a methyl group,
It is a halogen atom or a cyano group, and R ³² is a methyl group . At least one of R ³³ , R ³⁴ , R ³⁵ , R ^36, and R ³⁷ is a hydrocarbon group having 6 or less carbon atoms, and the rest may be the same or different, and a hydrogen atom, a methyl group, a halogen atom, And a cyano group. )

As R ²¹ in the general formula (2) and R ³¹ in the general formula (3), the same groups as R ¹¹ in the general formulas (1A) and (1B) can be introduced. R ²² in the general formula (2) and the general formula (3)
As R ³² in, a group similar to R ¹² in the general formulas (1A) and (1B) can be introduced.

In the general formula (2), even when all hydrogen atoms are introduced as R ^{23 to} R ²⁶ , the structure becomes flexible as compared with the adamantyl derivative and the like, which is preferable, but R ^{23 to} R ²⁶ are preferable. When a hydrocarbon group having 6 or less carbon atoms is introduced into at least one of the above, the symmetry becomes small, which is advantageous from the viewpoint of improving the solubility. Examples of the hydrocarbon group that can be introduced at this time include a methyl group, an ethyl group and an isopropyl group, with the methyl group being particularly preferable. Hydrocarbon groups such as those mentioned here have the same general formula (3) as R
It can be introduced as any one of ^{33 to} R ³⁷ .

[0039] In general formula (4), as the heterocyclic group which may be introduced as R ^44, cyclobutane ring, cyclopentane ring, cyclohexane ring, cycloheptane ring, cyclooctane ring or bridged hydrocarbon thereto it was introduced Things, spiro heptane, spiro rings such as spiro octane,
Norbonyl ring, bornene ring, menthyl ring, menthane ring,
Steroids such as terpene rings, Tujan, Sabinen, Tujon, Karan, Karen, Pinan, Norpinan, Bornan, Fencan, Tricyclene, Cholesteric ring, Tanjusan, Digitaloid ring, Camouflage ring,
Examples thereof include isocamphor ring, sesquiterpene ring, sandton ring, diterpene ring, triterpene ring, and steroid saponins, and examples of the hydrophilic group that can be introduced as R ⁴⁵ include a hydroxyl group, a carboxyl group, a carbonyl group, and a sulfonyl group. Can be mentioned.

As the repeating unit represented by the general formula (4), for example, those represented by the following general formula (5) can be used.

[0041]

[Chemical 14] (In the general formula (5), R ⁴⁶ represents a hydrogen atom, a methyl group,
It is a halogen atom or a cyano group. )

In the first photosensitive composition of the present invention, the high molecular polymer is either a homopolymer having only the repeating unit described above or a copolymer having another repeating unit. Also, it is used as an alkali-soluble resin. In the case of a copolymer, for example, a monomer having an alicyclic skeleton, a monomer whose alkali solubility is changed by an acid, and a monomer having an alkali-soluble group are added to a hydroxyalkyl ester side group. It can be used in combination with a monomer having a chain, that is, a repeating unit represented by any one of the above general formulas (1) to (4). At this time, the amount of the alkali-soluble compound having a functional group in the side chain is preferably about 20 to 80 mol%. If it is less than 20 mol%, the dry etching resistance is lowered, while if it exceeds 80 mol%, the solubility change in the alkali developing solution cannot be achieved and pattern formation may be impossible. However, when a monomer having an alicyclic skeleton is combined as a copolymerization component, to the extent that the dry etching resistance is not hindered,
The repeating unit represented by any one of the above general formulas (1) to (4) may be 20 mol% or less.

As the monomer having an alicyclic skeleton which can be copolymerized, for example, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, or a bridged hydrocarbon is introduced into these. Spiro ring such as sponge, spiroheptane, spirooctane,
Norbonyl ring, bornene ring, menthyl ring, menthane ring,
Steroids such as terpene rings, Tujan, Sabinen, Tujon, Karan, Karen, Pinan, Norpinan, Bornan, Fencan, Tricyclene, Cholesteric ring, Tanjusan, Digitaloid ring, Camouflage ring,
Examples include methacrylic acid, acrylic acid, α-cyanoacrylic acid, ethylene, vinyl alcohol, and hydroxystyrene having a side chain of isocamphor ring, sesquiterpene ring, Sandton ring, diterpene ring, triterpene ring, and steroid saponins. .

Furthermore, the repeating unit represented by the above general formulas (1) to (4) and a conjugation length of 4 or more and 1
By copolymerizing with a polymerizable compound containing 2 or less aromatic rings,
You may use it as a copolymer. Such a copolymer has improved solubility in a resist solvent and an alkali developing solution, and also has improved dry etching resistance. Conjugate length is 4 or more 1
Examples of the polymerizable compound having 2 or less aromatic rings include vinylnaphthalene, vinylnaphthol, naphthylmethacrylate, and naphthylacrylate. The α-position of these monomers may be substituted with an aliphatic hydrocarbon group, an alkoxy group, a halogen atom, or a cyano group. Further, anthracene can be used instead of naphthalene.

In the aromatic ring having a conjugation length of 4 or more and 12 or less, absorption which is remarkable in the benzene ring for light of 193 nm moves to the long wavelength side. Therefore, 1
3 μm for benzene ring per 1 μm for 93 nm light
The strong absorbance exceeding 0 is relaxed to about 3 to 5 on the naphthalene ring, for example. Therefore, the transmittance at 193 nm is remarkably improved. Further, since such a compound is an aromatic ring, the adhesiveness, solubility, dry etching resistance and the like of conventional resists containing a benzene ring are not impaired.

However, the absorption of the aromatic ring having a conjugation length of 4 or more and 12 or less for the light of 193 nm is smaller than that of the benzene ring, but is considerably larger than that of the aliphatic cyclic compound. Therefore, in order to prepare a resist for the wavelength of 193 nm, it is effective to use it as a copolymer in combination with the repeating units represented by the above general formulas (1) to (4).

The copolymer containing an aromatic ring having a conjugation length of 4 or more and 12 or less is desired to transmit at least 10% of light having a wavelength of 193 nm. In order to achieve this, it is preferable to determine the introduction amount of the aromatic ring having a conjugate length of 4 or more and 12 or less according to the resist film thickness. Specifically, when the resist film thickness is 1 μm or more, the amount of the aromatic ring introduced is 2
When the film thickness is 0% or less and the film thickness is 0.5 μm or more and less than 1 μm,
When the introduction amount of the aromatic ring is 30% or less and the film thickness is 0.3 μm or more and less than 0.5 μm, the introduction amount of the aromatic ring is 50% or less and when the film thickness is 0.2 μm or more and less than 0.3 μm,
The introduction amount of aromatic rings is preferably 70% or less, and the introduction amount of aromatic rings is preferably 100% or less when the film thickness is less than 0.2 μm.

The copolymer containing an aromatic ring having a conjugation length of 4 or more and 12 or less is 30% with respect to light having a wavelength of 193 nm.
It is more preferable to have the above transmittance. In order to secure the transmittance of 30%, it is desired to determine the introduction amount of the aromatic ring according to the resist film thickness as follows. That is, when the resist film thickness is 1 μm or more, 10% or less,
20% or less when 0.5 μm or more and less than 1 μm, 0.3
30 μm or less when μm or more and less than 0.5 μm, 0.2 μm
When it is m or more and less than 0.3 μm, it is preferably 50% or less, when it is 0.16 μm or more and less than 0.2 μm, 70% or less, and when it is less than 0.16 μm, it is preferably 100%.

In order to secure the solubility at the time of development, the ratio of the aromatic ring having a conjugation length of 4 or more and 12 or less in the copolymer is preferably 1% or more, and preferably 5% or more. More preferable. In addition, in order to further improve the adhesion between the resist film and the substrate, the ratio of the aromatic ring as described above in the copolymer is most preferably 15% or more.

These aromatic rings having a conjugation length of 4 or more and 12 or less are excellent in dry etching resistance and therefore can function as an aliphatic cyclic compound. However, since the transparency is slightly inferior, the aromatic ring having a conjugation length of 4 or more and 12 or less is more preferable when used in combination with the repeating unit represented by the above general formulas (1) to (4).

Examples of the monomer whose alkali solubility is changed by an acid include esters such as t-butyl ester, isopropyl ester, ethyl ester, methyl ester and benzyl ester; ethers such as tetrahydropyranyl ether; t- Butoxy carbonate,
Alkoxycarbonates such as methoxycarbonate and ethoxycarbonate; trimethylsilyl ether,
Silyl ethers such as triethylsilyl ether, triphenylsilyl ether, etc., isopropyl ester, tetrahydropyranyl ester, tetrahydrofuranyl ester, methoxyethoxymethyl ester, 2-
Trimethylsilylethoxymethyl ester, 3-oxocyclohexyl ester, isobornyl ester, trimethylsilyl ester, triethylsilyl ester, isopropyldimethylsilyl ester, di-t-butylmethylsilyl ester, oxazole, 3-alkyl 1,
3-oxazoline, 4-alkyl-5-oxo-1,3
Oxazoline, esters such as 5-alkyl-4-oxo-1,3-dioxolane, t-butoxycarbonyl ether, t-butoxymethyl ether, 4-pentenyloxymethyl ether, tetrahydropyranyl ether, tetrahydrothiopyranyl ether, 3 -Bromotetrahydropyranyl ether, 1-methoxycyclohexyl ether, 4-methoxytetrahydropyranyl ether, 4-methoxytetrahydrothiopyranyl ether, 1,4-dioxan-2-yl ether, tetrahydrofuranyl ether, tetrahydrothiofuranyl ether, 2,3 , 3a, 4,5,6,7,7a-octahydro-7,8,8-trimethyl-4,7-methanobenzofuran-2-yl ether, t-butyl ether, trimethylsilyl ether Ethers such as triethylsilyl ether, triisopropylsilyl ether, dimethylisopropylsilyl ether, diethylisopropylsilyl ether, dimethylthexylsilyl ether, t-butyldimethylsilylether, methylene acetal, ethylidene acetal, 2,2,2-trichloroethylidene Acetals and other acetals, 1-t-butylethylidene ketal, isopropylidene ketal (acetonide), cyclopentylidene ketal, cyclohexylidene ketal, ketals such as cycloheptylidene ketal, methoxymethylene acetal, ethoxymethylene acetal, dimethoxy Methylene orthoester, 1-methoxyethylidene orthoester, 1-
Cyclic orthoesters such as ethoxyethylidene orthoester, 1,2-dimethoxyethylidene orthoester, 1-N, N-dimethylaminoethylidene orthoester, 2-oxacyclopentylidene orthoester, trimethylsilyl ketene acetal, triethylsilyl ketene acetal Silyl ketene acetals such as t-butyl dimethyl silyl ketene acetal, di-t-butyl silyl ether, 1,3,1 ', 1',
3 ', 3'-tetraisopropyldisiloxanilidene ether, tetra-t-butoxydisiloxane-1,3-
Non-cyclic silyl ethers such as diylidene ether, dimethyl acetal, dimethyl ketal, bis-2,2,2-trichloroethyl acetal, bis-2,2,2-trichloroethyl ketal, diacetyl acetal, diacetyl ketal Acetals and ketals, 1,3-dioxane, 5-methylene-1,3-dioxane, 5,5-dibromo-1,3-dioxane, 1,
Cyclic acetals and ketals such as 3-dioxolane, 4-bromomethyl-1,3-dioxolane, 4,3'-butenyl-1,3-dioxolane and 4,5-dimethoxymethyl-1,3-dioxolane. , O-
Examples include methacrylic acid, acrylic acid, α-cyanoacrylic acid, vinyl alcohol, and hydroxystyrene having a side chain of cyanohydrins such as trimethylsilyl cyanohydrin, O-1-ethoxyethyl cyanohydrin, and O-tetrahydropyranyl cyanohydrin.

Examples of the monomer having an alkali-soluble group include methacrylic acid, acrylic acid, α-cyanoacrylic acid, α-chloroacrylic acid, vinyl alcohol, hydroxystyrene, hydroxyethyl methacrylic acid and hydroxyethyl. Examples thereof include acrylic acid. The ratio of each polymer component in the copolymer is not particularly limited as long as it satisfies the conditions described above, but can be appropriately changed depending on the solubility of the resin and the like.

It is preferable that the above-mentioned high molecular weight polymer does not contain an aromatic substituent because the transparency at 193 nm is remarkably improved. Specifically, the absorbance at 193 nm of this polymer is preferably 2 or less per 1 micron. Here, 193n of high molecular weight polymer
In order for the absorbance of m to be 2 or less per 1 micron, it is desirable to use a monomer in which an acidic substituent and an alicyclic compound are combined as shown below. Propanone oxime or propanal oxime group, hydroxyiminopentanone, alkyl group containing ketone oxime structure such as dimethylglyoxime, dicarboxylic acid imide such as succinimide or pyrrolidinedione, or N-
Alkyl group containing hydroxysuccinimide structure, substituent containing dicarbonylmethylene structure such as cyclopentene 1,3 dione and acetylacetone, 3methyl-2,4 pentanedione, carboxyl group, substituent having sulfamide structure, polysubstituted sulfonyl Examples include an alkyl group containing a methane structure, an alkyl group containing a thiol such as hexanethiol, an alcohol containing an enol structure such as hydroxycyclopentenone, a substituent containing a furfuryl alcohol structure, and an alkyl group containing an amic acid structure. To be

However, such compounds have poor solubility in organic solvents and very poor solubility in alkaline developers. If it is attempted to increase the solubility in an alcal developer, the adhesiveness between the obtained resist pattern and the substrate will deteriorate, and the pattern will peel. In addition, the properties of alkali solubility and the adhesiveness of the obtained pattern are contradictory to dry etching resistance and the dissolution inhibiting effect. Therefore, when each property is imparted to a separate polymerizable compound and a plurality of kinds of such monomers are copolymerized, the obtained effect may be reduced.

The inventors of the present invention have made extensive studies by paying attention to the fact that the performance of the photosensitive composition can be further improved by adding two or more of the above-mentioned characteristics to one kind of monomer. I obtained such knowledge. That is, as a result of molecular orbital calculation, it was found that a monomer formed by esterifying a tertiary alcohol functions as a dissolution inhibiting group because it is easily decomposed by an acid to form an alkali-soluble group. This is because the substance produced by the reaction with the acid catalyst is the primary or secondary
This is because it is thermodynamically stable as compared with the decomposition product of an esterification compound of a higher-grade alcohol. Therefore, a polymer containing a tertiary alcohol ester is suitable as a component of the photosensitive composition because it can increase the difference in the dissolution rate in the developing solution between the part that is decomposed by an acid and has high solubility and the part that is not decomposed. is there. Furthermore, when the alcohol here is a cyclic compound, dry etching resistance can be improved. However, when this cyclic compound has a structure such as an adamantyl derivative which is bulky and has high rigidity, it is difficult to react with an acid which is a catalyst, which may lead to a decrease in sensitivity when used as a photosensitive composition. It became clear from the scientific calculation. From these considerations, the inventor of the present invention blended a polymer compound having a repeating unit represented by any one of the general formulas (1) to (4) described above as a main component of a photosensitive composition to suppress dissolution. It has been found that a resist pattern having a high dry etching resistance can be formed while giving an effect.

In particular, the compound represented by the above general formula (2) or (3) is more advantageous than the polymer compound having a skeleton such as an adamantyl derivative for the following reasons.

First, the basic skeleton of the polymer compound to be blended in the photosensitive composition used as a resist requires some flexibility. When a predetermined region of the resist film dissolves in the developing solution, it usually dissolves in the form of a random coil. For this reason, when the flexibility of the polymer chain is not sufficient like the adamantyl derivative, crystallization occurs or a liquid crystal state is formed, which prevents uniform dissolution.
The random coil referred to here is a state that occurs when an amorphous polymer is dissolved in a solvent, and the radius of gyration of the polymer chain is proportional to the degree of polymerization of 0.5 to 0.6.

Next, the motion of the molecular chain can be predicted by performing a molecular dynamics calculation (MD).
For example, when the hydrogen atom of the carboxylic acid of polymethacrylate is esterified with an aliphatic cyclic olefin having a solid structure such as adamantyl or tetradecanyl, and the degree of polymerization is calculated as 50, it is confirmed that the movement of the molecular chain is restricted. On the other hand, when a 6-membered ring such as cyclohexane or menthyl is introduced into the above-mentioned compound, the substituent of such a 6-membered ring can be changed between the hull type and the chair type, so that the polymer chain Increases flexibility.

Furthermore, if a substituent such as a methyl group is added to the aliphatic cyclic olefin, the solubility becomes high.
When such a substituent is introduced, the number of conformations that can be taken by the polymer chain increases, so the entropy increases, and as a result, the free energy of mixing decreases during dissolution and the solubility increases. Explained.

When a hydroxyl group or a carboxylic acid is added to these aliphatic cyclic hydrocarbons, the adhesion to the substrate and the solubility in the developing solution are improved. Such an aliphatic cyclic hydrocarbon is
For example, it can be synthesized by the following procedure. First, cyclohexane, menthol, norbornene, isobornene, tricyclodecanyl, or adamantane is oxidized to obtain cyclohexanediol, menthanediol, norbornenediol, isobornenediol, tricyclodecanediol, or adamantanediol. The desired aliphatic cyclic hydrocarbon is obtained by esterifying the diol thus obtained with acrylic acid or methacrylic acid. Alternatively, it can be synthesized using a carboxylic acid such as cyclohexanecarboxylic acid, menthanecarboxylic acid, norbornenecarboxylic acid, isobornenecarboxylic acid, tricyclodecanylcarboxylic acid, and adamantanecarboxylic acid. In this case, first, these carboxylic acids are oxidized to give cyclohexanol carboxylic acid, menthol carboxylic acid, norbornenol carboxylic acid, isoborneenol carboxylic acid, tricyclodecanol carboxylic acid, adamantanol carboxylic acid, etc. To get Then, the obtained compound may be ester-bonded with acrylic acid or methacrylic acid.

The repeating unit represented by any of the above general formulas (1) to (4) is preferably about 5 to 80 mol% in the solid content of the first photosensitive composition of the present invention, 30 It is more preferably about 60 mol%. When the content of the repeating unit described above is less than 5 mol%, it is difficult to sufficiently exert the effects of the present invention. On the other hand, if it exceeds 80 mol%, the solubility in the resist solvent and the developing solution may be impaired.

Here, the method for synthesizing the polymer or copolymer having the repeating unit represented by the above general formula will be described as an example. For example, first, each monomer is dissolved in a predetermined solvent, for example, toluene, THF (tetrahydrofuran) or the like, and radical polymerization is further performed using AIBN (azobisisobutyronitrile) or the like as an initiator. At this time, living anionic polymerization or living cationic polymerization may be used depending on the case. Next, the polymerized polymer is dropped into a poor solvent to precipitate a solid content. The poor solvent can be selected according to the polarity of the polymer. For example, hexane can be used in the case of a highly polar polymer, and methanol, ethanol, water, etc. can be used as a poor solvent in the case of a less polar polymer. By sufficiently drying the solid content thus obtained in a vacuum, the high molecular polymer contained in the first photosensitive composition can be obtained.

The weight average molecular weight of the high molecular weight polymer obtained by the above-mentioned procedure is preferably 3,000 or more and 100,000 or less, more preferably 5,000 or more and 20,000 or less. If the weight average molecular weight is less than 3000, film formation becomes extremely difficult during coating, while 100
If it exceeds 000, dissolution in a resist solvent and a developing solution may be difficult.

Since the above-mentioned high molecular weight polymers have photosensitivity even at an irradiation dose of several hundreds mJ / cm ² or more, they can be used alone without addition of other photosensitizer components. Can be prepared as a photosensitive material. However, from the viewpoint of durability of the lens material, the irradiation dose during exposure is 200 mJ / cm ² or less, and further 50 mJ / cm ^2.
It is desired to be about cm ² or less.

Therefore, in the first invention, a compound capable of generating an acid upon irradiation with actinic radiation (hereinafter referred to as a photoacid generator) is blended as a photosensitizer with respect to a high molecular polymer. You may mix | blend a dissolution inhibitor with the 1st photosensitive composition further as needed.

In this case, a photoacid generator containing no aromatic ring (for example, CMS-105, DAM-301, NDI).
-105 and EPI-105 (manufactured by Midori Kagaku Co., Ltd.) and a dissolution inhibitor (such as those having adamantane-tert-butyl ester or cholic acid tert-butyl ester bonded) may be blended to prepare a photosensitive composition. . However, in order to prevent the decrease in heat resistance, it is desirable to add a compound having an aromatic ring as a photoacid generator or a dissolution inhibitor.

Examples of the aromatic compound photoacid generator include triphenylsulfonium triflate, diphenyliodonium triflate and naphthoquinonediazide. Specific examples of photoacid generators that can be used are shown in the following chemical formulas.

[0068]

[Chemical formula 23]

[0069]

[Chemical formula 24]

[0070]

[Chemical 25]

[0071]

[Chemical formula 26]

[0072]

[Chemical 27]

[0073]

[Chemical 28]

[0074]

[Chemical 29]

[0075]

[Chemical 30]

[0076]

[Chemical 31]

[0077]

[Chemical 32]

[0078]

[Chemical 33]

[0079]

[Chemical 34]

[0080]

[Chemical 35]

[0081]

[Chemical 36]

[0082]

[Chemical 37] In the above formula, C ¹ and C ² form a single bond or a double bond, R ⁰ is a hydrogen atom, a fluorine atom, an alkyl group or an aryl group which may be substituted with a fluorine atom, R ¹ , R
² may be the same as or different from each other and each represents a monovalent organic group, and R ¹ and R ² may be bonded to each other to form a ring structure.

It is most preferable to use a conjugated polycyclic aromatic compound in order not to impair the transparency for single wavelength light which is the object of the present invention.

The conjugated complex aromatic ring means that a plurality of aromatic rings have a definite molecular structure in a conjugated state, and conjugation means that every other double bond is close to a plane. Represents an aligned state.

Specific examples of the aromatic compound include naphthalene ring, anthracene ring, phenanthrene ring, pyrene ring, naphthacene ring, chrysene ring, 3,
4-benzophenanthrene ring, perylene ring, pentacene ring, and picene ring. Further, a pyrrole ring, a benzofuran ring, a benzothiophene ring, an indole ring, a benzoxazole ring, a benzothiazole ring, an indazole ring, a chromene ring, a quinolinzinnoline ring, a phthalazine ring, a quinazoline ring, a dibenzofuran ring, a carbazole ring, an acridine ring, and a phene ring. A nantrizine ring, a phenanthroline ring, a phenazine ring, a thianthrene ring, an indolizine ring, a naphthyridine ring, a purine ring, a pteridine ring, and a fluorene ring correspond to this. In particular, a compound containing an aromatic ring such as a naphthalene ring, an anthracene ring, and a phenanthrene ring is desirable because it has high transparency and dry etching resistance. These aromatic ring compounds can be introduced into the main chain skeleton or the side chain skeleton of the photoacid generator or the dissolution inhibitor.

Specific examples of the photoacid generator include onium salts having a naphthalene skeleton and a dibenzothiophene skeleton, sulfonates, sulfonyls, and sulphamide compounds. More specifically, NAT-1
05 and NDS-105 and other sulfonium salts, naphthalene-containing chlorinated triazines such as NDI-106, sulphonic acid imides such as naphthalidyl triflate (Midori Kagaku), dibenzothiophene derivative onium salts (Daikin Chemical) , And naphthalene bisulfone. These examples are summarized in the chemical formulas below.

[0087]

[Chemical 38]

[0088]

[Chemical Formula 39] In the above formula, X ⁻ is CF ₃ SO ₃ ⁻ , BF ₄ ⁻ , AsF.
₆ ^-, PF ₆ ^- or, SbF ₆ ^- is.

[0089]

[Chemical 40]

[0090]

[Chemical 41]

[0091]

[Chemical 42] In the formula, Z represents an alkyl group.

[0092]

[Chemical 43] When these photo-acid generators are blended, the addition amount thereof is preferably at least 0.1% by weight and less than 20% by weight with respect to the alkali-soluble resin. The reason for this is that if the amount of the photosensitive composition added is less than 0.1% by weight, the sensitivity may be lowered, while if it is 20% by weight or more, the coating film performance may be significantly reduced. is there.

The photoacid generator generates an acid upon irradiation with actinic radiation, and the catalytic action thereof decomposes the repeating units represented by the general formulas (1) to (4). Therefore, in the first photosensitive composition, the compound having a dissolution inhibiting effect (dissolution inhibitor) is not essential. However, in order to make the difference in dissolution rate between the exposed and unexposed areas of the resist film sufficiently large, a compound having a substituent that decomposes with an acid to form an alkali-soluble group is used as a dissolution inhibitor. It is desirable to blend. As the dissolution inhibitor, for example, US Pat.
28 and 4603101, JP-A-63-27.
Of the compounds described in JP 829, etc., any compound in which the aromatic ring is a condensed polycyclic aromatic ring as described above can be used.

Alternatively, a compound obtained by substituting a part or all of the hydroxy terminus of a condensed polycyclic aromatic ring compound having a carboxylic acid or a phenolic hydroxyl group introduced therein with an acid-decomposable protecting group is used as a dissolution inhibitor. You may use it as an agent. In this case, the protecting group that can be decomposed with an acid is, for example, te
It may be rt-butyl ester, tert-butyl carbonate, tetrahydropyranyl group, acetal group, trimethylsilyl group, or the like. More specifically exemplifying such compounds, polyhydroxy compounds of naphthalene or anthracene, and tert-butyl carbonate of their novolac-type condensation compounds; tert-butyl carbonate of naphtholphthalein; tert-butyl carbonate of quinazaline or quinizarin; naphthalene Or ter of anthracene polyhydroxy compounds and their novolac-type condensation compounds
t-butyloxycarbonyl methylated product; tert-butyloxycarbonyl methylated product of naphtholphthalein and the like.

These acid-decomposable group-containing compounds can be blended alone or as a mixture of two or more kinds in combination with the above-mentioned alkali-soluble resin.

The amount of such a compound added to the alkali-soluble resin is preferably at least 3% by weight and less than 50% by weight, more preferably 10% by weight and 30% by weight. The reason for this is that if the addition amount of the dissolution inhibitor is less than 3% by weight, it becomes difficult to obtain sufficient resolution, while if it is 50% by weight or more, the coating property or the dissolution rate at the time of development becomes remarkable. This is because there is a risk that it will decrease.

Examples of the substituent decomposable by an acid include esters such as t-butyl ester, isopropyl ester, ethyl ester, methyl ester and benzyl ester; ethers such as tetrahydropyranyl ether; t-butoxycarbonate, Alkoxycarbonates such as methoxycarbonate and ethoxycarbonate; silyl ethers such as trimethylsilyl ether, triethylsilyl ether and triphenylsilyl ether, such as isopropyl ester, tetrahydropyranyl ester, tetrahydrofuranyl ester, methoxyethoxymethyl ester, 2- Trimethylsilylethoxymethyl ester, 3-oxocyclohexyl ester, isobornyl ester, trimethylsilyl ester, triethyl Riruesuteru, isopropyl dimethylsilyl ester, di -t- butyl methyl silyl ester, oxazole, 3-alkyl 1,3-oxazoline, 4-alkyl-5-oxo-1,3-oxazoline,
Esters such as 5-alkyl-4-oxo-1,3-dioxolane, t-butoxycarbonyl ether, t-
Butoxymethyl ether, 4-pentenyloxymethyl ether, tetrahydropyranyl ether, tetrahydrothiopyranyl ether, 3-bromotetrahydropyranyl ether, 1-methoxycyclohexyl ether, 4
-Methoxytetrahydropyranyl ether, 4-methoxytetrahydrothiopyranyl ether, 1,4-dioxan-2-yl ether, tetrahydrofuranyl ether, tetrahydrothiofuranyl ether, 2,3,3
a, 4,5,6,7,7a-octahydro-7,8,8
-Trimethyl-4,7-methanobenzofuran-2-yl ether, t-butyl ether, trimethylsilyl ether, triethylsilyl ether, triisopropylsilyl ether, dimethylisopropylsilyl ether,
Ethers such as diethyl isopropyl silyl ether, dimethyl sexyl silyl ether, t-butyl dimethyl silyl ether, methylene acetal, ethylidene acetal, acetals such as 2,2,2-trichloroethylidene acetal, 1-t-butyl ethylidene ketal, Ketals such as isopropylidene ketal (acetonide), cyclopentylidene ketal, cyclohexylidene ketal, cycloheptylidene ketal, methoxymethylene acetal, ethoxymethylene acetal, dimethoxymethylene orthoester, 1-methoxyethylidene orthoester, 1-ethoxy Ethylidene orthoester, 1,2-dimethoxyethylidene orthoester, 1-N, N-dimethylaminoethylidene orthoester, 2-o Cyclic orthoesters such as sacyclopentylidene orthoester, trimethylsilylsilyl ketene acetal, triethylsilyl ketene acetal, silyl ketene acetals such as t-butyldimethylsilyl ketene acetal, di-t-butyl silyl ether, 1,3,3. 1 ', 1', 3 ', 3'-tetraisopropyldisiloxanilidene ether, tetra-
Silyl ethers such as t-butoxydisiloxane-1,3-diylidene ether, dimethyl acetal, dimethyl ketal, bis-2,2,2-trichloroethyl acetal, bis-2,2,2-trichloroethyl ketal, dye Acyclic acetals and ketals such as acetyl acetal and diacetyl ketal, 1,3-dioxane, 5-methylene-1,3-dioxane, 5,5-dibromo-1,3-dioxane, 1,3-dioxolane,
4-Bromomethyl-1,3-dioxolane, 4,3'-
Cyclic acetals and ketals such as butenyl-1,3-dioxolane and 4,5-dimethoxymethyl-1,3-dioxolane, O-trimethylsilyl cyanohydrin, O-1-ethoxyethyl cyanohydrin,
And cyanohydrins such as O-tetrahydropyranyl cyanohydrin.

The dissolution inhibitor having a group as described above is
The chemical formulas are summarized below.

[0099]

[Chemical 44]

[0100]

[Chemical formula 45]

[0101]

[Chemical formula 46] In the above formula, tBoc is, - (C = O) O -C (CH 3)
₃ is shown and n is an integer.

[0102]

[Chemical 47]

[0103]

[Chemical 48]

[0104]

[Chemical 49] In the above formula, tBoc is, - (C = O) O -C (CH 3)
₃ is shown.

[0105]

[Chemical 50]

[0106]

[Chemical 51]

[0107]

[Chemical 52]

[0108]

[Chemical 53]

[0109]

[Chemical 54]

[0110]

[Chemical 55] When the dissolution inhibitor as described above is blended, the high molecular weight polymer in the first photosensitive composition contains a repeating unit represented by any one of formulas (1) to (4) and an alkali It can be a copolymer with a vinyl compound having an alkali-soluble group such as methacrylic acid which imparts solubility.

Alternatively, in the first invention, the same effect can be obtained not only by incorporating the above-mentioned dissolution inhibiting agent, but also by introducing a dissolution inhibiting group into the alkali-soluble resin. That is, in addition to the repeating unit represented by any one of the above general formulas (1) to (4), a unit having a dissolution inhibiting group may be contained in the copolymer. In this case, the proportion of the dissolution inhibiting group in the copolymer is 10 mol% or more and 50 mol% or more.
The following is preferable. If it is less than 10 mol%, the dissolution inhibiting function cannot be sufficiently exhibited, and it becomes difficult to dissolve the unexposed portion to resolve the pattern. On the other hand, if it exceeds 50 mol%, the photosensitive material becomes too hydrophobic, and the adhesiveness to the substrate is extremely lowered, which makes it difficult to form a pattern.

The photosensitive composition of the first invention is most preferably a composition prepared by blending a photo-acid generator and, if necessary, a dissolution inhibitor with the following high molecular weight polymer. As the high molecular weight polymer, t-butyl methacrylate, t-
Acrylic or vinyl compound having t-butyl ester such as butyl-3-naphthyl-2-propenoate, trimethylsilyl methacrylate or tetrahydropyranyl methacrylate, trimethylsilyl ester or tetrahydropyranyl ester in the side chain, and the above-mentioned general formula (1) And a copolymer obtained by copolymerizing the repeating unit represented by any one of (4) to (4) is most preferable.

In the case of a high molecular weight polymer containing an alicyclic compound, it is more preferable to add a conjugation length shift type dissolution inhibitor having a medium to low molecular weight since it has good transparency.

It is effective to add 1 to 50% of a dissolution inhibitor containing an aromatic compound having a conjugation length of 4 to 12 to a high molecular weight copolymer containing an ester of a tertiary alicyclic alcohol. The aromatic compound having a conjugation length of 4 to 12 is more preferably a naphthalene derivative in consideration of stability and cost.

Examples of the dissolution inhibitor containing an aromatic compound having a conjugation length of 4 to 12 include tetrahydropyranyl group and t-
Examples thereof include naphthol novolak protected with a butyl group and t-butoxy group, and naphthylimide.

The ester of tertiary alicyclic alcohol can be resolved without adding an additive, but has a conjugation length of 4-12.
Addition of 5% or more of the dissolution inhibitor containing the aromatic compound described above further improves the dry etching resistance and the solubility.
However, if it exceeds 30%, the transparency may be deteriorated and the pattern shape may be deteriorated. Therefore, the addition amount of the dissolution inhibitor is more preferably 5 to 30%.

Specifically, in the case of a copolymer of γ-((1-methyl) cyclopentyl) methacrylate and methacrylic acid, the addition of 15 to 25% of tetrahydropyranyl protected naphthol novolak results in dry etching resistance. And the solubility is improved.

Further, the first photosensitive composition may further contain other components, if necessary. Specifically, other polymers such as epoxy resin, polymethyl methacrylate, polymethyl acrylate, propylene oxide, ethylene oxide copolymer, polystyrene and the like,
An amine compound for improving environment resistance, a basic compound such as a pyridine derivative, a surfactant for modifying a coating film, a dye as an antireflection agent, and the like can be appropriately added.

The photosensitive composition of the present invention comprises, for example, a high molecular weight polymer as described above, a compound which generates an acid upon irradiation with actinic radiation, and a compound whose solubility is changed by the action of an acid in some cases. It is usually prepared as a varnish by dissolving in a solvent and filtering. Examples of the organic solvent here include ketone-based solvents such as acetone, silokuhexanone, methyl ethyl ketone, and methyl isobutyl ketone; methyl cellosolve, methyl cellosolve acetate,
Cellosolve solvents such as ethyl cellosolve acetate and butyl cellosolve acetate; ethyl acetate, butyl acetate,
Examples thereof include ester solvents such as isoamyl acetate, γ-butyl lactone, and methyl 3-methoxypropionate. Furthermore, depending on the type of high molecular weight copolymer,
A mixed solvent obtained by adding dimethyl sulfoxide, dimethylformaldehyde, N-methylpyrrolidinone, or the like to these may be used for improving the solubility. Further, propionic acid derivatives such as methyl methylpropionate, lactic acid esters such as ethyl lactate, PGMEA (propylene glycol monomethyl ether acetate) and the like have low toxicity and can be preferably used. In the present invention, such a solvent may be used alone or in combination of two or more, and may further contain an aliphatic alcohol such as toluene, xylene and isopropyl alcohol.

Next, the second photosensitive composition of the present invention will be described in detail.

The high molecular polymer represented by the following general formula (6) is blended in the second photosensitive composition.

[0122]

[Chemical 56] In the general formula (6), R ⁵¹ , R ⁵² and R ⁵³ may be the same or different and each is a hydrogen atom, a halogen atom, a cyano group or a monovalent organic group, and R ⁵⁴ is 1
The valent alicyclic organic groups, R ⁵⁵ and R ^{56, which} may be the same or different, are divalent groups containing at least one of C, N, S or O, and R ⁵⁷ is an acid group. It is a monovalent organic group that decomposes by a catalytic action to generate an alkali-soluble group. Further, p, q and r are p ≧ 0, q> 0, and r ≧ 0.
(However, p and r are not 0 at the same time).

In the high molecular polymer represented by the general formula (6), R ⁵¹ , R ⁵² and R ⁵³ are each a hydrogen atom, a halogen atom, a cyano group, or a monovalent organic group such as a methyl group and an ethyl group. Groups.

Further, the monovalent alicyclic organic group R ⁵⁴ has a function of imparting dry etching resistance,
Examples thereof include cyclic cyclo compounds and cyclic bicyclo compounds represented by the general formula C _n H _2n (n is an integer of 3 or more), and condensed rings thereof. Specifically, a cyclobutane ring,
Cyclopentane ring, cyclohexane ring, cycloheptane ring and those into which substituents or bridged hydrocarbons are introduced, spiroheptane, spirooctane and other spiro rings, norbornyl ring, adamantyl ring, bornene ring, menthyl ring, menthane ring Steroid ring such as terpene ring, Tujan, Sabinene, Tujon, Karan, Karen, Pinan, Norpinane, Bornan, Fencan, Tricyclene, Cholesteric ring, Tanjusan, Digitaloid, Shaunon ring, Isocamphor ring, Sesquiterpene ring, Sandton ring , Diterpene rings, triterpene rings, and steroid saponins.

As shown in the above general formula (6), in the high molecular polymer used in the second invention, the acidic substituent for imparting alkali solubility is a specific divalent organic group R ^55. And R ⁵⁶ to the polymer backbone. Thus, by separating the polar group for imparting alkali solubility from the polymer main chain, the influence of a bulky alicyclic organic group can be avoided. However, when the number of atoms between the polymer main chain and the polar group increases, the polymer may expand and the glass transition temperature (T _g ) may decrease. In order to prevent this, the number of atoms of the substituent introduced as R ⁵⁵ and R ⁵⁶ is preferably 6 or less. However, this does not apply when the divalent substituents R ⁵⁵ and R ⁵⁶ are cyclic. R ⁵⁵ and R ⁵⁶
Is not particularly limited as long as it is a divalent group containing at least one of C, N, S or O, but from the viewpoint of compound stability and dry etching resistance, a methylene group, an ethylene group, or the like is used. Groups containing carbon are preferred.

Specific examples of such a polymer structural unit include, for example, 4-pentenoic acid and 6-heptenoic acid, organic compounds having a double bond and a carboxyl group at the terminal of each molecule; bicyclopentadienecarboxylic acid. An organic compound having a carboxyl group at the other end of a cyclic compound having a double bond such as an acid can be used.

The high molecular weight polymer represented by the general formula (6) may contain an active methylene group and another structural unit having another acidic substituent such as fluoroalkyl alcohol.

Further, in the second invention, a part of the acidic substituent in the above-mentioned high molecular polymer is decomposed and eliminated by an acid-catalyzed reaction to produce an alkali-soluble group R ^57.
May be capped by. Examples of the substituent R ^{57 which} is separated and eliminated by an acid-catalyzed reaction include esters such as t-butyl ester, isopropyl ester, ethyl ester and methyl ester, ethers such as tetrahydropyranyl ether, ethoxyethyl ether and tetrahydrofuranyl ether, Examples thereof include acetals, alkoxy carbonates such as t-butoxy carbonate, methoxy carbonate and ethoxy carbonate, and silyl ethers such as trimethylsilyl ether and triethylsilyl ether.

As the substituent R ^{57 which} is decomposed and eliminated by an acid-catalyzed reaction, a compound having a tertiary ester structure as a general structure is preferable, and examples thereof include 2-methyl-2-adamantyl and 1-methylcyclohexanol. Of 3
Alicyclic compounds of the grade can be used. Thus R
^When an alicyclic compound is introduced as ⁵⁷ , this substituent also has an effect of imparting dry etching resistance, so that p in the general formula (6) may be 0. When a photosensitive composition containing such a high molecular polymer is used, the substituent R ⁵⁷ is eliminated due to an acid-catalyzed reaction in the exposed portion of the resist film to exhibit alkali solubility, while the unexposed portion is alicyclic. Since the skeleton remains, it is possible to form a resist pattern having excellent dry etching resistance.

In the second photosensitive composition, the high molecular polymer represented by the general formula (6) is an acrylic acid derivative of the alicyclic compound described above, a carboxylic acid derivative for imparting alkali solubility, and In some cases, it can be easily obtained by copolymerizing a compound in which the alkali-soluble group of the alkali-soluble compound is protected with an acid-decomposable group. At this time, a naphthalene derivative for improving dry etching resistance may be copolymerized. However, considering the transparency of the resist to short-wavelength light, it is preferable to copolymerize it with a compound that does not have a molecular skeleton such as a benzene nucleus that has a large light absorption in the short-wavelength region. It is desired that the absorbance of the combined light with respect to light having a wavelength of 193 nm is 2 or less per 1 μm.

However, the copolymerization ratio q of the structural unit containing a carboxylic acid is preferably 5 to 40% in the copolymer, and more preferably 20 to 40%. If the copolymerization ratio of this structural unit is less than 5%, the alkali solubility of the high molecular polymer may be insufficient, while if it exceeds 40%, the resist pattern may be formed. This is because the sensitivity of 1 tends to decrease.

In order to obtain sufficient dry etching resistance, the copolymerization ratio of the alicyclic organic group-containing structural unit is preferably 20% or more in the copolymer. That is,
In the general formula (6), when p is not 0, (p
It is desired that / (p + q + r)) is 0.2 or more. On the other hand, when p = 0, R ⁵⁷ is 1 as described above.
It is preferable that it is a valent alicyclic organic group and (r / (q + r)) is 0.2 or more.

In the photosensitive composition of the second invention, the high molecular weight polymer as described above has an average molecular weight of 1000 to 1
It is preferably set in the range of 00000. If the average molecular weight of the high molecular weight polymer is less than 1000,
It is disadvantageous in forming a resist film having sufficient mechanical strength, while the average molecular weight of the high molecular polymer is 100,000.
This is because if it exceeds 0, it becomes difficult to form a resist pattern having good resolution.

Examples of the compound (hereinafter referred to as a photo-acid generator) which generates an acid upon irradiation with actinic radiation, which is contained in the photosensitive composition of the second invention, include sulfonyl,
Onium salt compounds such as iodonium and compounds such as sulfonyl ester as described in the first photosensitive composition can be used.

In the photosensitive composition of the second invention, the photoacid generator is preferably incorporated in an amount of 0.1 part by weight or more and 30 parts by weight or less, and more preferably 0.1 part by weight or less, based on the whole photosensitive composition. Is 0.3 part by weight or more and 15 parts by weight or less. If the blending amount of the photo-acid generator is less than 0.1 part by weight, it may be difficult to form a resist pattern with high sensitivity. On the other hand, if it exceeds 30 parts by weight,
When the resist film is formed, its mechanical strength may be impaired. Also, depending on the type of the photo-acid generator, the light transmittance of the photosensitive composition film at 193 nm may be impaired.

Further, the photosensitive composition of the second invention comprises
In addition to the components described above, a compound having a group that is decomposed by the catalytic action of an acid and exhibits alkali solubility may be separately added as a dissolution inhibitor. Here, examples of the deterrent group that is easily decomposed by an acid include the groups capable of capping the acidic group of the above-mentioned polymer. Specifically, the compound as described in the first photosensitive composition can be used as the dissolution inhibitor.

The dissolution inhibitors may be used in combination of two or more kinds in order to maintain the dissolution rate and the characteristics as a resist.

When a dissolution inhibitor is added to the photosensitive composition of the second invention, the total amount of the dissolution inhibiting groups in the composition is 5 to 95% with respect to the total acrylic acid derivative units. Furthermore, it is desirable to select the blending amount so that it falls within the range of 10 to 60%. this is,
This is because if the proportion of the dissolution inhibiting group is less than 5%, the contrast between the exposed portion and the unexposed portion cannot be obtained, while if it exceeds 95%, the adhesion of the resist film to the substrate may be impaired.

The photosensitive composition of the second invention comprises the above-mentioned copolymer containing at least a group for imparting dry etching resistance and an alkali-soluble group.
It is prepared by dissolving an acid generator and, if necessary, a dissolution inhibitor in an organic solvent, and filtering this solution.
As the organic solvent here, the solvent described in the photosensitive composition of the first invention can be used.

Next, the third photosensitive composition of the present invention will be described in detail.

A high molecular polymer containing at least one repeating unit represented by the following general formula (7) and a repeating unit represented by the following general formula (8) is blended in the third photosensitive composition. .

[0142]

[Chemical 57] In the general formula (7), R ⁶¹ and R ⁶² may go be the same or different, a halogen atom, a hydrogen atom, an alkyl group, but an aromatic group or a monovalent substituent,, R ⁶¹ and At least one of R ⁶² is a halogen atom.

[0143]

[Chemical 58] In the general formula (8), R ⁶³ and R ^64, which may be the same or different, a halogen atom, a hydrogen atom, an alkyl group, but an aromatic group or a monovalent substituent,, R ⁶³ and R ^At least one of ⁶⁴ is a halogen atom. R ⁶⁵
And R ⁶⁶ represents a hydrogen atom, an alkyl group, an aromatic group or a monovalent substituent.

Further, a high molecular polymer having a repeating unit represented by the following general formula (9) can also be used.

[0145]

[Chemical 59] In the general formula (9), R ⁶⁷ represents a halogen atom, and R ⁶⁸
Represents a hydrogen atom, an alkyl group, an aromatic group or a monovalent substituent.

The high molecular polymer blended in the photosensitive composition of the third invention contains at least one repeating unit represented by the above general formulas (7) to (9),
These repeating units can be referred to as acrylic acid, an acid anhydride and ester derivatives thereof in which a halogen atom is introduced as a substituent at the α-position. Since the halogen atom is introduced at the α-position, the high molecular polymer, which is the main component of the photosensitive composition of the third invention, has a main chain cutting function,
This made it possible to increase the sensitivity to irradiation with actinic radiation.

In the above general formulas (7) to (9),
The halogen atom which can be introduced as R ⁶¹ , R ⁶² , R ⁶³ , R ⁶⁴ and R ⁶⁷ is not particularly limited, but a chlorine atom is particularly preferable from the viewpoint of sensitivity and compound stability. Also, R
^{Examples of} the alkyl group that can be introduced as ⁶¹ , R ⁶² , R ⁶³ and R ⁶⁴ include a methyl group and an ethyl group, and examples of the aromatic group include a phenyl group and a naphthyl group.
Further, examples of the monovalent substituent include an alkylsilyl group. Here mentioned alkyl group, an aromatic group and a monovalent substituent, R ⁶⁵ at the general formula (8), R
⁶⁶ and R ⁶⁸ in the general formula (9) can be introduced.

More specifically, examples of the halogen-containing acrylic acid, acid anhydride, and ester derivative thereof as described above include α-chloroacrylic acid, dichloromaleic acid, dichloromaleic acid anhydride, and monochloromaleic acid. Is mentioned. Examples of esters of these compounds include alkyl groups such as methyl, ethyl, propyl, n-butyl and t-butyl; aromatic compounds such as phenyl and naphthyl.

When a group that is easily decomposed by an acid-catalyzed reaction is introduced into the repeating unit as described above, it is possible to obtain a chemical amplification effect of increasing the dissolution rate of the exposed portion of the resist film. Specifically, the general formula (8)
At least one of R ⁶⁵ and R ^{66 in} the above or R ⁶⁸ in the general formula (9) is eliminated by an acid catalyst,
A group that easily generates a carboxylic acid may be introduced. Examples of the group that is easily decomposed by an acid-catalyzed reaction include secondary or tertiary esters such as t-butyl ester, isopropyl ester, ethyl ester and methyl ester; tetrahydropyranyl ether, ethoxyethyl ether, t-
Examples thereof include ethers such as butoxyethyl ether, acetals; alkoxycarbonates such as t-butoxycarbonate, methoxycarbonate, and ethoxycarbonate; and silicon-containing compounds such as trimethylsilyl, triethylsilyl, and triphenylsilyl.

When a cyclic compound such as an aromatic ring or an alicyclic compound is introduced into the above repeating unit,
Dry etching resistance can be imparted to the high molecular weight polymer. In order to obtain such an effect, a cyclic compound may be introduced into at least one of R ⁶⁵ and R ⁶⁶ in the general formula (8) or R ⁶⁸ in the general formula (9). Cyclic compounds include phenyl, naphthyl,
Aromatic compounds such as anthranil and pyridyl and their derivatives may be introduced into R ⁶⁵ and R ⁶⁶ or R ⁶⁸ . Considering the correspondence to the deep ultraviolet region such as ArF excimer laser, the alicyclic compound introduced here is preferably one having a small absorption in the 193 nm region.

Examples of the alicyclic compound include those represented by the general formula C
_Examples thereof include cyclic compounds represented by _n H _2n (n is an integer of 3 or more), polycyclic compounds, and structures in which they are bonded. Specifically, compounds having a skeleton of cyclobutane, cyclopentane, cyclohexane, cycloheptane, those having a substituent introduced therein, and those having a bridged hydrocarbon introduced therein, spiroheptane, spirooctane, etc. Steroid skeletons such as spiro compounds, norbornyl, adamantyl, bornene, menthyl, menthane, cyclic terpenoid compounds, tsujang, sabinene, tsujon, karan, karen, pinan, norpinane, bornan, fencan, tricyclene, cholesteric derivatives; tanjusan, digitaroid, camphor, Examples are isocamphor, sesquiterpenes, sandones, diterpenes, triterpene derivatives, steroid saponins and the like. Adamantyl, dicyclopentyl ester, cyclohexyl ester, cycloheptyl ester, norbornyl ester, bornyl ester, camphanyl ester, menthyl ester, adamantyl ester, and derivatives thereof.

In synthesizing the above-mentioned esters, the ester may be introduced into the carboxyl group of the monomer and then subjected to the polymerization reaction. Particularly in the case of an acid anhydride, the polymer is synthesized. It is also possible to introduce an ester structure by reacting with an alcohol.

In the third invention, the above general formula (7)
The high molecular polymer containing the repeating unit represented by any of (9) to (9) may be a copolymer obtained by copolymerizing these with other structural units.

The compound which can be copolymerized is not particularly limited as long as it is a compound containing a polymerizable group, and examples thereof include derivatives of acrylic acid and methacrylic acid; compounds having a double bond in the cyclic structure, such as norbornene and the like. Derivative;
Aromatic compounds such as styrene and hydroxystyrene can be mentioned.

Among these copolymerization components, when an ester or ether having a polar group into which a group that is easily decomposed by an acid-catalyzed reaction is introduced, a chemical amplification effect can be imparted to the polymer compound. Examples of such a structural unit include those represented by the following general formula (10).

[0156]

[Chemical 60] In the general formula (10), R ⁶⁹ is a hydrogen atom, an alkyl group,
R ⁷⁰ is an aromatic group or a monovalent substituent, and R ⁷⁰ is a monovalent substituent which is easily removed by an acid.

Examples of the alkyl group that can be introduced as R ⁶⁹ include methyl and ethyl, and examples of the aromatic group include phenyl and naphthyl. Further, examples of the monovalent substituent include an alkylsilyl group and the like. On the other hand, as the monovalent substituent that can be easily eliminated by an acid that can be introduced as R ⁷⁰ , for example, t-butyl, tetrahydropyran, ethoxyethyl, alkylsilyl and the like groups described above can be introduced.

That is, in the high molecular weight polymer blended in the third photosensitive composition of the present invention, the side chain of a monomer such as an acrylic acid derivative having a halogen at the α-position, and this monomer A monovalent substituent that is easily removed by an acid can be introduced into at least one of the other monomers to be copolymerized.

It is preferable that the total amount of monovalent groups that are easily eliminated by an acid is 15% or more in the high molecular weight polymer. When the total amount of such monovalent groups is less than 15%, it becomes difficult to sufficiently increase the dissolution rate of the exposed area.

In order to secure dry etching resistance by the copolymerization component, it is desired that the structure includes an ester structure as shown for the halogenated compound structural unit. Examples of such a structural unit include those represented by the following general formula (11).

[0161]

[Chemical formula 61] In the general formula (11), R ⁷¹ is a hydrogen atom, an alkyl group,
R ⁷² is an aromatic group or a monovalent substituent, and R ⁷² is a monovalent organic group containing an aromatic ring or a cyclic aliphatic substituent.

Examples of the alkyl group, aromatic group and monovalent substituent which can be introduced as R ⁷¹ are the same as those for R ⁶⁹ described above. Further, R ⁷² is preferably an alicyclic compound for the reasons described above.

That is, in the high molecular weight polymer blended in the third photosensitive composition of the present invention, the side chain of a monomer such as an acrylic acid derivative having a halogen at the α-position, and this monomer A cyclic substituent for imparting dry etching resistance can be introduced into at least one of the other monomers to be copolymerized.

The total amount of monovalent organic groups containing aromatic rings or cyclic aliphatic substituents is 10 in the high molecular polymer.
% Or more and 90% or less is preferable. If it is less than 10%, it may be difficult to obtain sufficient dry etching resistance, while if it exceeds 90%, the adhesion of the resist film to the substrate may deteriorate.

In the high molecular weight polymer blended in the third photosensitive composition of the present invention, the above-mentioned general formulas (7) to (9) are used.
The proportion of the repeating unit represented by is determined by the combination with the copolymerization component and the like, but is preferably at least 10% or more. If it is less than 10%, it may be difficult to obtain sufficient sensitivity.

In the third photosensitive composition, the high molecular weight polymer as described above has an average molecular weight of 1,000 to 1,000.
It is desirable to set it in the range of 00. What if
When the average molecular weight of the high molecular weight polymer is less than 1000,
It is disadvantageous in forming a resist film having sufficient mechanical strength, while the average molecular weight of the polymer compound is 100,000.
If it exceeds, it becomes difficult to form a resist pattern having good resolution.

The amount of the high molecular polymer containing at least one repeating unit represented by the general formulas (7) to (9) in the photosensitive composition may be appropriately determined depending on the film thickness, the solvent and the like. Although it is possible, it is usually about 5 to 30 wt%.

Examples of the compound (hereinafter referred to as a photo-acid generator) which generates an acid upon irradiation with actinic radiation, which is contained in the photosensitive composition of the third invention, include sulfonyl,
Onium salt compounds such as iodonium, and compounds such as sulfonyl esters described in the first photosensitive composition can be used.

In the third photosensitive composition, the amount of the photoacid generator is preferably 0.1 based on the total amount of the photosensitive composition.
It is preferably not less than 30% by weight and not more than 0.
It is more preferably 3% by weight or more and 15% by weight or less. When the content of the photo-acid generator is less than 0.1% by weight, it becomes difficult to form a resist pattern with high sensitivity. On the other hand, when it exceeds 30% by weight, the film formability during resist coating is impaired. There is a risk. In addition, depending on the type of the photo-acid generator to be blended, the light transmittance of the photosensitive composition film at 193 nm when using an ArF excimer laser as a light source may decrease.

Further, to the photosensitive composition of the third invention, in addition to the above-mentioned components, a compound having a group which is decomposed by the catalytic action of an acid and exhibits alkali solubility, may be separately added as a dissolution inhibitor. Absent. Here, examples of the deterrent group that is easily decomposed by an acid include groups capable of capping the acidic group of the polymer compound described above. Specifically, as the dissolution inhibitor, the compounds described in the first photosensitive composition can be used.

The dissolution inhibitor may be used in combination of two or more kinds in order to maintain the dissolution rate and the characteristics as a resist.

When a dissolution-inhibiting group is added to the third photosensitive composition, the total amount of the dissolution-inhibiting groups in the composition is 5 to 90%, more preferably 20%, based on all polymer units.
It is desirable to select the compounding amount so that it is within the range of 50%. This is because if the proportion of the dissolution inhibiting group is less than 5%, the contrast between the exposed portion and the unexposed portion cannot be sufficiently obtained, while if it exceeds 90%, the adhesion of the resist film to the substrate may be impaired. Because.

Further, in order to reduce the effect of deactivation due to adsorption of basic contaminants in the environment, which is one of the drawbacks of the chemically amplified resist, on the resist characteristics, a small amount of basic compound may be added. I do not care. As the basic compound, a compound that does not impair the original resist sensitivity can be used. Specific examples include, for example, pyridine derivatives such as t-butylpyridine, benzylpyridine, and pyridinium salts, and aromatic amines. Certain aniline derivatives, such as N-methylaniline, N-ethylaniline, N, N '
-Dimethylaniline, diphenylaniline, N-methyldiphenylamine, indene and the like. The blending amount of such a basic substance is preferably 0.1 to 50 mol% with respect to the photoacid generator, and more preferably 1
Is about 15 mol%. If it is less than 1 mol, it will be difficult to sufficiently obtain the effect of adding a basic substance.
This is because if it exceeds 1%, the original sensitivity of the resist may be significantly reduced.

The third photosensitive composition has the above general formula (7).
To at least one of the repeating units represented by (9)
A high molecular polymer as described above containing a species, a photoacid generator,
And, if necessary, dissolve the dissolution inhibitor in an organic solvent,
Prepared by filtering this solution.

As the organic solvent here, those described in the first photosensitive composition can be used.

Next, a pattern forming method using the photosensitive composition of the present invention will be described. First, a resist varnish dissolved in an organic solvent as described above is applied on a predetermined substrate by spin coating or dipping, and then 200
A resist film is formed by drying at a temperature of not higher than 70 ° C, preferably at 70 to 120 ° C. The substrate here is, for example, a silicon wafer, a silicon wafer on the surface of which various insulating films and electrodes, and wiring are formed, a blank mask, GaAs, and AlG.
Examples thereof include III-V group compound semiconductor wafers such as aAs. Alternatively, a chromium or chromium oxide vapor deposition mask, an aluminum vapor deposition substrate, an IBPSG coated substrate, a PSG coated substrate, an SOG coated substrate, a carbon film sputtered substrate or the like may be used.

Next, the resist film is exposed by irradiating it with an actinic ray through a predetermined mask pattern or directly scanning the actinic ray on the surface of the resist film. The actinic rays here include, for example, i-line, h-line and g-line of a low pressure mercury lamp.
Rays, xenon lamp light, various ultraviolet rays such as deep ultraviolet rays such as excimer laser light such as KrF and ArF, X-rays, electron rays, gamma rays, neutron rays, and ion beams can be used. The effects of the photosensitive composition of the present invention are most exerted on the exposure used.

Subsequently, the resist film after pattern exposure is appropriately subjected to heat treatment (baking) at about 50 to 180 ° C., preferably at about 60 to 120 ° C. by heating on a hot plate or in an oven or infrared irradiation. By such heat treatment,
In the exposed portion of the resist film, the acid generated by exposure acts as a catalyst and reacts with a compound having a substituent that is decomposed by the acid. At this time, if the heat treatment temperature is less than 50 ° C,
It becomes difficult to sufficiently cause the reaction between the acid generated by the photo-acid generator and the compound having a substituent decomposable by the acid. On the other hand, when the temperature exceeds 180 ° C., both exposed and unexposed portions of the resist film are exposed. There is a possibility that excessive decomposition or curing may occur.

Thus, in the compound having a substituent decomposable by an acid, the substituent is decomposed to exhibit alkali solubility. In some cases, the same effect as the above-described post-exposure bake may be obtained by leaving it at room temperature for a sufficiently long time.

After that, the resist film after baking is developed by a dipping method, a spray method, a paddle method or the like to selectively dissolve and remove the exposed portion of the resist film to form a desired pattern. At this time, it is preferable to use an alkali developing solution as the developing solution, and specifically, an inorganic alkaline aqueous solution such as sodium hydroxide, sodium carbonate, sodium silicate, and sodium metasilicate, an aqueous tetramethylammonium hydroxide solution, and trimethylhydroxy. Examples thereof include organic alkali aqueous solutions such as ethyl ammonium hydroxide aqueous solution, and those obtained by adding alcohols and surfactants thereto. The concentration of these alkaline aqueous solutions is preferably 15% by weight or less from the viewpoint of making a sufficient difference in dissolution rate between exposed and unexposed areas. The substrate and the resist film (resist pattern) after the development treatment are appropriately rinsed with water or the like and further dried.

The resist pattern formed by using the photosensitive composition of the present invention is excellent as follows. For example,
Since the first photosensitive composition has extremely good alkali solubility, the resist pattern using the first photosensitive composition does not have cracks or surface roughness, and the pattern does not collapse.

As described above, the second photosensitive composition has a structural unit in which an acidic substituent is bonded to the polymer main chain through at least one atom, and a side chain has an alicyclic organic group. The main component is a high molecular weight polymer containing a structural unit. Therefore, a resist pattern formed using such a photosensitive composition can avoid all the drawbacks associated with conventional compositions containing a bulky alicyclic compound and acidic group copolymer polymer. It was That is, the resist pattern formed using the second photosensitive composition is
Since the adhesiveness to the substrate is particularly good, peeling does not occur during development with an alkaline solution. Moreover, at the time of development, a desired region is uniformly dissolved, and the resolution of the obtained pattern is good.

The third photosensitive composition contains, as a main component, a polymer copolymer containing maleic anhydride having a halogen atom introduced at the α-position, maleic acid, acrylic acid, or an ester compound thereof as a constituent unit. There is. Therefore, when the resist film formed by coating such a photosensitive composition is irradiated with actinic radiation, the main chain of the high molecular polymer in the exposed portion is cut and the molecular weight is reduced. On the other hand, the polarity of the exposed area is changed by the catalytic action of the acid, and the solubility in the alkaline developer is generated, so that the dissolution rate contrast is generated.
That is, since the third photosensitive composition has a polymer main chain scission function in addition to the solubilization of the exposed portion by the action of a conventional acid catalyst, a high contrast change can be easily obtained. .

As described above, even when any of the first to third photosensitive compositions is used, a pattern having extremely good resolution can be formed with high reproducibility. Therefore, by using this pattern as an etching mask, it is possible to remove 0.1
It is possible to faithfully transfer an ultrafine pattern of about 5 μm. For example, when the resist pattern is formed on a silicon wafer as a substrate as described above, the silicon wafer substrate is processed by, for example, processing the substrate in a parallel plate reactive ion etching apparatus using CF ₄ gas. Can be accurately patterned. Further, when a transparent substrate having a chromium layer formed on the surface is used as the substrate and the above resist pattern is formed on this substrate, for example, an aqueous cerium ammonium nitrate solution is used as an etching agent to select the chromium layer. It is possible to form the light-shielding film with high precision by etching selectively.

Here, taking the case of using a silicon wafer as a substrate, the fine processing steps of the electronic component of the present invention will be described with reference to the drawings.

FIG. 1 is a cross sectional view schematically showing a part of the manufacturing process of an electronic component in the case where a positive type alkali developing resist is used.

First, as shown in FIG. 1A, the resist film 13 formed on the silicon wafer 11 is irradiated with the exposure light 14 having a predetermined pattern. The exposure light generates an acid in the exposed portion of the resist film 13.

Then, 50 to 180 on a hot plate
30 ~ 300 seconds at ℃, or 5 ~ 6 in the oven
By heating after 0 minute exposure, the acid generated in the exposed portion 16 of the resist film decomposes, for example, an acid-decomposable compound as shown in FIG. 1B, and the exposed portion 16 is selectively alkali-soluble. Present. After that, the exposed portion 16 is selectively dissolved by an alkali developing solution to form a desired resist pattern 17 on the resist film 13 as shown in FIG.

Then, using the obtained resist pattern 17 as an etching mask, the silicon wafer 11 is etched with CF ₄ gas. As a result,
As shown in (d), the resist pattern 17 is accurately transferred to the silicon wafer 11.

Finally, Hakuri-10, Positive
Photoreist Stripper R-1
The resist pattern 17 on the surface of the substrate is removed by using a resist stripping solution such as 0 to form a silicon wafer 18 on which a desired pattern as shown in FIG.
Is obtained.

Incidentally, in addition to the steps described above, it does not matter even if other steps are added. For example,
Step of forming a flattening layer as an underlayer of the resist film, pretreatment step for improving adhesion between the resist film and the underlayer, rinse step of removing the developing solution with water after developing the resist film, and ultraviolet ray before dry etching The re-irradiation step can be appropriately performed.

[0192]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. (Example I) In this example, a photosensitive composition was prepared by blending a high molecular polymer represented by the general formula (1) or the general formula (4), and its characteristics were examined.

First, the monomers for synthesizing the high molecular weight polymer to be blended in the photosensitive composition of this example were synthesized as follows. (Monomer (I-1)) 44 g of 1-methylbutanol and 50.5 g of triethylamine were mixed with 100 methylene chloride.
It was dissolved in g to obtain a solution. While maintaining the temperature of this solution at -20 ° C, methacryloyl chloride
g was added dropwise to the solution to prepare a mixed solution. The temperature of the obtained mixed solution was gradually raised and stirred at 20 ° C. for 2 hours, and then triethylamine hydrochloride was filtered off. Finally recrystallize to give γ-((1-methyl) cyclobutyl)
51 g of methacrylate was obtained. (Monomer (I-2)) 50 g of 1-methylbutanol
Γ- by the same procedure as in the synthesis of the above-mentioned monomer (I-1) except changing to 1-methylpentanol
((1-methyl) cyclopentyl) methacrylate 5
3 g was obtained. (Monomer (I-3)) 57 g of 1-methylbutanol
Γ- by the same procedure as the synthesis of the above-mentioned monomer (I-1) except changing to 1-methylhexanol
((1-methyl) cyclohexyl) methacrylate 6
8 g was obtained. (Monomer (I-4)) 63 g of 1-methylbutanol
Except that the 1-methylheptanol was replaced with 1-methylheptanol by the same procedure as in the synthesis of the above-mentioned monomer (I-1).
((1-Methyl) cycloheptyl) methacrylate 7
4 g was obtained. (Monomer (I-5)) 69 g of 1-methylbutanol
Γ- by the same procedure as in the synthesis of the above-mentioned monomer (I-1) except changing to 1-methyloctanol
((1-methyl) cyclooctyl) methacrylate 8
0 g was obtained. (Monomer (I-6)) (1S, 2S, 3R, 5S)-
17 g of (+)-Pinandiol and 10 g of triethylamine were dissolved in 20 g of methylene chloride to obtain a solution. The temperature of this solution was maintained at −20 ° C., and 10 g of methacryloyl chloride was added dropwise to the solution so as not to generate heat to prepare a mixed solution. The temperature of the obtained mixed solution was gradually raised and stirred at 20 ° C. for 2 hours, and then triethylamine hydrochloride was filtered off. Finally, recrystallization was performed to obtain 20 g of a monomer represented by the following chemical formula.

[0194]

[Chemical formula 62] (Monomer (I-7)) 2-methylisoborneol 1
20 g of methylene chloride with 7 g and 10 g of triethylamine
To obtain a solution. While maintaining the temperature of this solution at -20 ° C, 10 g of methacryloyl chloride so as not to generate heat
Was dropped thereinto to prepare a mixed solution. The temperature of the obtained mixed solution was gradually raised, and the mixture was stirred at 20 ° C. for 2 hours, and then triethylamine hydrochloride was filtered off. Finally, it was recrystallized to obtain 21 g of γ-((2-methyl) isobornyl) methacrylate. (Monomer (I-8)) acetic anhydride and p-menthane-3,
The 8-diol was stirred and mixed in acetone and refluxed. Then, this was extracted with ether to obtain p-mental-3-acetoxy, 8-ol.

This product was dissolved in 20 g of methylene chloride together with 10 g of triethylamine to obtain a solution. While maintaining the temperature of this solution at -20 ° C, 10 g of methacryloyl chloride was added dropwise to the solution so as not to generate heat, to prepare a mixed solution. The temperature of the obtained mixed solution was gradually raised, and the mixture was stirred at 20 ° C. for 2 hours, then triethylamine hydrochloride was filtered off and recrystallized. Finally, it was hydrolyzed with a strong alkali to obtain 20 g of γ- (p-menthan-3-ol) methacrylate. (Monomer (I-9)) Menthanediol, acrylic acid chloride, and butyllithium were mixed in tetrahydrofuran to obtain a THF solution, which was stirred at room temperature for 8 hours.

The THF solution after stirring was reacted with a saturated sodium hydrogen carbonate aqueous solution, and ether was added. The reaction solution was separated into two layers, the aqueous layer was extracted with ether, and the organic layers were combined and washed with a saturated aqueous sodium hydrogen carbonate solution. Then, it dried with saturated sodium chloride aqueous solution and anhydrous sodium sulfate.

After concentration, the obtained oily substance was separated by a silica gel column to obtain γ- (p-menthan-3-ol) acrylate. (Monomer (I-10)) 1-methylpentanol 50
g and 50.5 g of triethylamine were added to methylene chloride 10
It was dissolved in 0 g to obtain a solution. The temperature of this solution is -20 ° C.
Acryloyl chloride 45 so as not to generate heat while maintaining
g was added dropwise to the solution to prepare a mixed solution. The temperature of the obtained mixed solution was gradually raised and stirred at 20 ° C. for 2 hours, and then triethylamine hydrochloride was filtered off. Finally, it was recrystallized to obtain 51 g of γ-((1-methyl) cyclopentyl) acrylate. (Monomer (I-11)) 1-methylpentanol 5
By the same procedure as in the synthesis of the above-mentioned monomer (I-10) except changing to 7 g of 1-methylhexanol, γ
-((1-Methyl) cyclohexyl) acrylate 5
8 g was obtained. (Monomer (I-12)) 2-Methylnorbornene-2-
A solution was obtained by dissolving 13 g of all and 10 g of triethylamine in 20 g of methylene chloride. The temperature of this solution is -2
While maintaining the temperature at 0 ° C., 10 g of methacryloyl chloride was added dropwise to the solution so as not to generate heat, to prepare a mixed solution.
The temperature of the obtained mixed solution was gradually raised and stirred at 20 ° C. for 2 hours. Then, triethylamine hydrochloride was filtered off and recrystallized to obtain 17 g of γ-((2-methyl) norbornyl) methacrylate. (Monomer (I-13)) methacryloyl chloride 9.
THF with 3 g and 2-hydroxy-3-pinanone 15 g
It was dissolved in 50 ml to obtain a THF solution. While maintaining the temperature of the THF solution at 0 ° C., triethylamine 9.0
g was added thereinto to prepare a reaction solution. The reaction solution was stirred for 1 hour and further stirred at room temperature for 3 hours to obtain an ester compound produced by solvent extraction. Purification was performed by column chromatography. By using silica gel as a carrier and developing with toluene, a monomer represented by the following chemical formula was obtained.

[0198]

[Chemical formula 63] The infrared spectroscopic spectrum of the obtained compound is shown in FIG. Two
The 900～3000Cm ^-1 has appeared the absorption of C-H, the 1720 cm ^-1, and 1150 cm ^-1, has appeared the absorption of each C = O and C-O-C. (Monomer (I-14)) A monomer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above-mentioned monomer (I-13) except that methacryloyl chloride was changed to acryloyl chloride.

[0199]

[Chemical 64] (Monomer (I-15)) Adamantane-1-carboxylic acid and KMnO ₄ were subjected to an oxidation reaction using sodium hydroxide as a catalyst to obtain adamantane-1-ol, 4-carboxylic acid.

This product was dissolved in 20 g of methylene chloride together with 10 g of triethylamine to obtain a solution. While maintaining the temperature of this solution at −20 ° C., 10 g of acryloyl chloride was dropped into the solution so as not to generate heat to prepare a mixed solution. Gradually raise the obtained mixed solution,
After stirring for 2 hours, triethylamine hydrochloride was filtered off,
It was recrystallized. Finally, it was hydrolyzed with a strong alkali to obtain adamantane-4-carboxylic acid, 1-acrylate. 20 g of (monomer (I-16)) p-menthane-3,8-diol was dissolved in 20 g of methylene chloride together with 10 g of triethylamine to obtain a solution. While maintaining the temperature of this solution at −20 ° C., 10 g of acryloyl chloride was dropped into the solution so as not to generate heat to prepare a mixed solution. The obtained mixed solution was gradually raised and stirred for 2 hours, then triethylamine hydrochloride was filtered off and recrystallized. Finally, it was hydrolyzed with a strong alkali to obtain 20 g of 8-hydroxy-3-menthyl acrylate. (Monomer (I-17)) 1-methylcyclohexane-
4-carboxylic acid and KMnO ₄ are oxidized with sodium hydroxide as a catalyst to give 1-methylcyclohexane,
1-ol, 4-carboxylic acid was obtained.

This product was dissolved in 20 g of methylene chloride together with 10 g of triethylamine to obtain a solution. While maintaining the temperature of this solution at −20 ° C., 10 g of acryloyl chloride was dropped into the solution so as not to generate heat to prepare a mixed solution. Gradually raise the obtained mixed solution,
After stirring for 2 hours, triethylamine hydrochloride was filtered off,
It was recrystallized. Finally, hydrolyze with strong alkali to 1
-Methylcyclohexanone, 4-carboxylic acid was obtained.

The monomer (I-
Using 1) to (I-17), a high molecular polymer was synthesized as follows. 8.5 g of (polymer (PI-1)) γ-((1-methyl) cyclopentyl) methacrylate and 0.82 g of azobisisobutyronitrile (AIBN) were dissolved in 30 g of tetrahydrofuran (THF) to obtain a THF solution. ,
This THF solution was freeze-deaerated three times at a liquid nitrogen temperature under an argon atmosphere. After reacting this at 60 ° C. for 30 hours in an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 20 g of THF was further added. Then, 250 g of hexane was dropped with stirring to drop the reaction solution to reprecipitate it, and then filtered with a glass filter. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to obtain a high molecular polymer having a repeating unit represented by the following chemical formula. The yield was 6.85 g, and the weight average molecular weight of the obtained polymer was 1500 in terms of polystyrene.
It was 0.

[0203]

[Chemical 65] (In the formula, n is an integer.) (Polymer (PI-2)) γ-((1-methyl) cyclohexyl) methacrylate 9.2 g, and AIBN
0.82 g was dissolved in 20 g of THF, and freeze-deaerated three times at a liquid nitrogen temperature under an argon atmosphere. After reacting this at 60 ° C. for 30 hours in an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 20 g of THF was further added. Then, 250 g of hexane was dropped with stirring to drop the reaction solution to reprecipitate it, and then filtered with a glass filter. Finally, the solid content is 3 at 60 ° C.
After vacuum drying for a day, a polymer having a repeating unit represented by the following chemical formula was obtained. The yield was 7.6 g, and the weight average molecular weight was 15,000 in terms of polystyrene.
Met.

[0204]

[Chemical formula 66] (In the formula, n is an integer.) (Polymer (PI-3)) γ-((1-methyl) cyclopentyl) methacrylate 10.1 g, methacrylic acid 3.3 g, and AIBN 1.64 g in THF 30.
g, and freeze-deaerated three times at a liquid nitrogen temperature under an argon atmosphere. In an argon atmosphere,
After reacting at 60 ° C. for 30 hours, 2 ml of methanol was added to the reaction solution, and further 30 g of THF was added. Then, while stirring 500 g of hexane, the reaction solution was dropped one by one and reprecipitated, and then filtered through a glass filter. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to obtain a copolymer having a repeating unit represented by the following chemical formula. The yield was 10.65 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0205]

[Chemical formula 67] (In the formula, m and n are integers.) (Polymer (PI-4)) γ-((1-methyl) cyclopentyl) methacrylate was added to 11.0 g of γ-((1
A copolymer having a repeating unit represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above-mentioned polymer (PI-3) except that it was changed to -methyl) cyclohexyl) methacrylate. The yield was 11.3 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0206]

[Chemical 68] (In the formula, m and n are integers.) (Polymer (PI-5)) γ-((1-methyl) cyclopentyl) methacrylate 11.9 g of γ-((1-
A copolymer having a repeating unit represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above copolymer (PI-3) except that the copolymer was changed to methyl) cycloheptyl) methacrylate. The yield was 12.1 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0207]

[Chemical 69] (In the formula, m and n are integers.) (Polymer (PI-6)) γ-((1-methyl) cyclopentyl) methacrylate 12.8 g of γ-((1-
A copolymer having a repeating unit represented by the following chemical formula was obtained by the same procedure as the synthesis of the above-mentioned copolymer (PI-3) except that the copolymer was changed to methyl) cyclooctyl) methacrylate. The yield was 12.9 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0208]

[Chemical 70] (In the formula, m and n are integers.) (Polymer (PI-7)) γ-((1-methyl) cyclopentyl) methacrylate 13.4 g of γ-((2-
A copolymer having a repeating unit represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above copolymer (PI-3) except that the copolymer was changed to methyl) isobornyl) methacrylate. The yield was 13.9 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0209]

[Chemical 71] (In the formula, m and n are integers.) (Polymer (PI-8)) γ-((1-methyl) cyclopentyl) methacrylate is added to the above-mentioned monomer (I-
8) A copolymer having a repeating unit represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above copolymer (PI-3) except that the amount was changed to 13.6 g. The yield was 14.3 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0210]

[Chemical 72] (In the formula, m and n are integers.) (Polymer (PI-9)) γ-((1-methyl) cyclopentyl) methacrylate was changed to 9.2 g of γ-((1-methyl) cyclopentyl) acrylate. A copolymer having a repeating unit represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above-mentioned copolymer (PI-3) except for the above. The yield was 10.05 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0211]

[Chemical formula 73] (In the formula, m and n are integers.) (Polymer (PI-10)) γ-((1-methyl) cyclopentyl) methacrylate 10.1 g of γ-((1
A copolymer having a repeating unit represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above copolymer (PI-3), except that the copolymer was changed to -methyl) cyclohexyl) acrylate. The yield was 10.4 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0212]

[Chemical 74] (In the formula, m and n are integers.) (Polymer (PI-11)) γ-((1-methyl) cyclopentyl) methacrylate 12.6 g of γ-((2
A copolymer having a repeating unit represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above copolymer (PI-3), except that the copolymer was changed to -methyl) norbornyl) acrylate. The yield was 13.2 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0213]

[Chemical 75] (In the formula, m and n are integers.) (Polymer (PI-12)) γ- (p-menthane-3-
All) methacrylate 0.020 mol, vinylnaphthalene 0.025 mol, tetrahydropyranyl methacrylate 0.034 mol, and methacrylic acid 0.0
THF obtained by dissolving 21 mol in 20 g of THF
AIBN as a polymerization initiator in the solution 0.0125 mol
added. The THF solution (reaction solution) thus obtained was first freeze-deaerated three times at a liquid nitrogen temperature in an argon atmosphere. Then, after reacting for 30 hours at 60 ° C. under an argon atmosphere, 2 ml of methanol was added to the reaction solution.
While stirring 250 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, the solid content is vacuum dried at 60 ° C. for 3 days,
A copolymer represented by the following chemical formula was obtained. The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.
Met.

[0214]

[Chemical 76] (Polymer (PI-13)) Vinyl naphthalene 0.2
Other than changing to 5 mol of naphthyl methacrylate,
A copolymer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the polymer (PI-12) described above. The weight average molecular weight was 15,000 in terms of polystyrene.

[0215]

[Chemical 77] (Polymer (PI-14)) Vinyl naphthalene 0.2
A copolymer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the polymer (PI-12) except that the amount of vinyl naphthol was changed to 5 mol. The weight average molecular weight was 15,000 in terms of polystyrene.

[0216]

[Chemical 78] (Polymer (PI-15)) γ- (p-menthane-3-
All) 0.055 mol of methacrylate, 0.025 mol of vinyl naphthol acetate, and 0.020 mol of methacrylic acid were dissolved in 20 g of THF, and the resulting THF solution was mixed with 0.012 of AIBN as a polymerization initiator.
5 mol was added. The THF solution (reaction solution) thus obtained was first freeze-deaerated three times at a liquid nitrogen temperature in an argon atmosphere. Then, under an argon atmosphere, 60
After reacting for 30 hours at ℃, add 2m of methanol to the reaction solution.
1, and 20 g of THF was further added. Hexane 250
While stirring g, the reaction solution was dropped one by one to reprecipitate. The solid content obtained here was dissolved in a solution prepared by mixing 1N aqueous sodium hydroxide solution and THF at a ratio of 1: 1 and reacted at 60 ° C. to decompose the acetate. This was again reprecipitated in 500 g of hexane and filtered through a glass filter. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to obtain a copolymer represented by the following chemical formula. The weight average molecular weight of the obtained polymer was 15 in terms of polystyrene.
It was 000.

[0217]

[Chemical 79] (Polymer (PI-16)) γ- (p-menthane-3-
All) 0.075 mol of methacrylate and 0.025 mol of t-butyl vinyl naphthol in THF 20
g as a polymerization initiator and added to the resulting THF solution.
0.0125 mol of IBN was added. The thus-obtained THF (reaction liquid) solution was first freeze-deaerated three times at a liquid nitrogen temperature under an argon atmosphere. Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 20 g of THF was further added. While stirring 250 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to obtain a copolymer represented by the following chemical formula. The weight average molecular weight of the obtained polymer was 150 in terms of polystyrene.
It was 00.

[0218]

[Chemical 80] (Polymer (PI-17)) γ- (p-menthane-3-
All) acrylate 0.020 mol, vinylnaphthalene 0.025 mol, tetrahydropyranyl methacrylate 0.034 mol, and methacrylic acid 0.02.
1 mol was dissolved in 20 g of THF, and 0.0125 mol of AIBN as a polymerization initiator was added to the obtained THF solution. The THF solution (reaction solution) thus obtained was first freeze-deaerated three times at a liquid nitrogen temperature in an argon atmosphere. Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 20 g of THF was further added. After stirring 250 g of hexane and dropping the reaction solution one drop at a time for reprecipitation,
It was filtered through a glass filter. Finally, the solid content is 60 ° C.
Was vacuum-dried for 3 days to obtain a copolymer represented by the following chemical formula. The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0219]

[Chemical 81] (Polymer (PI-18)) Vinyl naphthalene 0.0
A copolymer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the polymer (PI-17) described above, except that 25 mol of naphthyl methacrylate was used. The weight average molecular weight of the obtained copolymer was 15,000.

[0220]

[Chemical formula 82] (Polymer (PI-19)) Vinyl naphthalene 0.0
A copolymer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above-mentioned polymer (PI-17) except that the vinyl naphthol was changed to 25 mol. The weight average molecular weight of the obtained copolymer was 15,000.

[0221]

[Chemical 83] (Polymer (PI-20)) γ- (p-menthane-3-
All) 0.055 mol of acrylate, 0.025 mol of vinyl naphthol acetate, and 0.020 mol of methacrylic acid were dissolved in 20 g of THF, and AIBN as a polymerization initiator was added to 0.0125 in an amount of 0.0125.
mol was added. THF solution (reaction solution) thus obtained
First, freeze deaeration was performed three times at a liquid nitrogen temperature under an argon atmosphere. Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 20 g of THF was further added. While stirring 250 g of hexane, the reaction solution was dropped one by one to reprecipitate. The solid content obtained here is dissolved in a solution of a 1N aqueous sodium hydroxide solution and THF mixed at a ratio of 1: 1,
The reaction was carried out at 60 ° C. to decompose the acetate. This was again reprecipitated in 500 g of hexane and filtered through a glass filter. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to obtain a copolymer represented by the following chemical formula. The weight average molecular weight of the obtained polymer was 150 in terms of polystyrene.
It was 00.

[0222]

[Chemical 84] (Polymer (PI-21)) γ- (p-menthane-3-
All) 0.075 mol of acrylate and 0.025 mol of t-butyl vinyl naphthol were dissolved in 20 g of THF, and the resulting THF solution was added with AIB as a polymerization initiator.
0.0125 mol of N was added. TH thus obtained
The F solution (reaction solution) was first freeze-deaerated three times at a liquid nitrogen temperature under an argon atmosphere. Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 20 g of THF was further added. While stirring 250 g of hexane, the reaction solution was dropped one by one to reprecipitate. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to obtain a copolymer represented by the following chemical formula. The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0223]

[Chemical 85] (Polymer (PI-22)) γ- (p-menthane-3-
All) methacrylate 0.020 mol, vinylnaphthalene 0.025 mol, tetrahydropyranyl acrylate 0.034 mol, and methacrylic acid 0.02.
1 mol was dissolved in 20 g of THF, and 0.0125 mol of AIBN as a polymerization initiator was added to the obtained THF solution. The THF solution (reaction solution) thus obtained was first freeze-deaerated three times at a liquid nitrogen temperature in an argon atmosphere. Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 20 g of THF was further added. After stirring 250 g of hexane and dropping the reaction solution one drop at a time for reprecipitation,
It was filtered through a glass filter. Finally, the solid content is 60 ° C.
Was vacuum-dried for 3 days to obtain a copolymer represented by the following chemical formula. The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0224]

[Chemical 86] (Polymer (PI-23)) Vinyl naphthalene 0.0
A copolymer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the polymer (PI-22) described above, except that the amount of naphthyl methacrylate was changed to 25 mol. The weight average molecular weight of the obtained polymer was 15 in terms of polystyrene.
It was 000.

[0225]

[Chemical 87] (Polymer (PI-24)) Vinyl naphthalene 0.0
A copolymer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above-mentioned polymer (PI-22) except that it was changed to 25 mol of vinylnaphthol. The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0226]

[Chemical 88] (Polymer (PI-25)) γ- (p-menthane-3-
All) acrylate 0.020 mol, vinylnaphthalene 0.025 mol, tetrahydropyranyl acrylate 0.034 mol, and methacrylic acid 0.021.
mol was dissolved in 20 g of THF, and 0.0125 mol of AIBN as a polymerization initiator was added to the obtained THF solution. The THF solution (reaction solution) thus obtained was
Freezing and degassing were performed three times at a liquid nitrogen temperature under an argon atmosphere. Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 20 g of THF was further added. While stirring 250 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, the solid content is 3 at 60 ° C.
After vacuum drying for one day, a copolymer represented by the following chemical formula was obtained. The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0227]

[Chemical 89] (Polymer (PI-26)) Vinyl naphthalene 0.0
Other than changing to 25 mol of naphthyl acrylate,
A copolymer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the polymer (PI-25) described above. The weight average molecular weight of the obtained polymer was 1500 in terms of polystyrene.
It was 0.

[0228]

[Chemical 90] (Polymer (PI-27)) Vinyl naphthalene 0.0
A copolymer represented by the following chemical formula by the same procedure as in the synthesis of the above-mentioned polymer (PI-25), except that 25 mol of naphthyl acrylate was used and tetrahydropyranyl acrylate was changed to 0.034 mol of tetrahydropyranyl methacrylate. Got The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0229]

[Chemical Formula 91] (Polymer (PI-28)) Vinyl naphthalene 0.0
Other than changing to 25 mol of naphthyl acrylate,
A copolymer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the polymer (PI-25) described above. The weight average molecular weight of the obtained polymer was 1500 in terms of polystyrene.
It was 0.

[0230]

[Chemical Formula 92] (Polymer (PI-29)) Vinyl naphthalene 0.0
A copolymer represented by the following chemical formula was obtained by the same procedure as in the synthesis of the above-mentioned polymer (PI-25) except that the vinyl naphthol was changed to 25 mol. The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0231]

[Chemical formula 93] (Polymer (PI-30)) γ-((2-methyl) isobornyl) methacrylate 0.020 mol, vinylnaphthalene 0.025 mol, tetrahydropyranyl methacrylate 0.034 mol, and methacrylic acid 0.
The obtained TH was obtained by dissolving 021 mol in 20 g of THF.
AIBN as a polymerization initiator in the F solution was 0.0125mo
1 was added. The THF solution (reaction solution) thus obtained is
First, freeze deaeration was performed three times at a liquid nitrogen temperature under an argon atmosphere. Then, at 60 ° C. under an argon atmosphere for 30
After reacting for 2 hours, add 2 ml of methanol to the reaction mixture,
Further, 20 g of THF was added. While stirring 250 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, add 6
It was vacuum dried at 0 ° C. for 3 days to obtain a copolymer represented by the following chemical formula. The weight average molecular weight of the obtained polymer is
It was 15,000 in terms of polystyrene.

[0232]

[Chemical 94] (Polymer (PI-31)) γ-((2-methyl) isobornyl) methacrylate was added to 0.020 mol of γ-
A copolymer represented by the following chemical formula was obtained by the same procedure as the synthesis of the polymer (PI-30) described above, except that the copolymer was changed to ((2-methyl) isobornyl) acrylate.
The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0233]

[Chemical 95] (Polymer (PI-32)) γ-((1-methyl) cyclohexyl) methacrylate 0.020 mol, vinylnaphthalene 0.025 mol, tetrahydropyranyl methacrylate 0.034 mol, and methacrylic acid 0.021 mol are dissolved in THF 20 g, AIBN as a polymerization initiator was added to the obtained THF solution in an amount of 0.0125.
mol was added. THF solution (reaction solution) thus obtained
First, freeze deaeration was performed three times at a liquid nitrogen temperature under an argon atmosphere. Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 20 g of THF was further added. While stirring 250 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to obtain a copolymer represented by the following chemical formula. The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0234]

[Chemical 96] (Procedure similar to the synthesis of the polymer (PI-32) described above, except that the polymer (PI-33) γ-((1-methyl) cyclohexyl) methacrylate was changed to γ-((1-methyl) cyclohexyl) acrylate. Thus, a copolymer represented by the following chemical formula was obtained: The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0235]

[Chemical 97] (Polymer (PI-34)) [gamma]-((1-methyl) cyclohexyl) methacrylate was replaced with the monomer (I-6) by the same procedure as in the synthesis of the polymer (PI-32) described above. A copolymer represented by The weight average molecular weight of the obtained polymer was 15,000 in terms of polystyrene.

[0236]

[Chemical 98] (Polymer (PI-35)) γ-((1-methyl) cyclopentyl) acrylate 7.9 g and AIBN 0.8
2 g and THF were dissolved in 30 g, and the obtained THF solution was freeze-deaerated three times at a liquid nitrogen temperature under an argon atmosphere. Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and 30 g of THF was further added. While stirring 500 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to synthesize a high molecular polymer. The yield of the obtained polymer was 10.65 g, and the weight average molecular weight was 15,000 in terms of polystyrene.

[0237]

[Chemical 99] (In the above formula, n is an integer.) (Polymer (PI-36)) Monomer (I-13) 3
g and AIBN 0.1 g as a polymerization initiator
After dissolving in 12 g of F and degassing the obtained THF solution (reaction solution), the reaction was carried out at 60 ° C. for 5 hours. Then, the reaction solution was gradually added dropwise to 100 ml of hexane, and the precipitated polymer solid was separated by filtration to obtain a polymer polymer represented by the following chemical formula.

[0238]

[Chemical 100] (In the above formula, n is an integer.) (Synthesis of Polymer (PI-37)) Monomer (I-1
3) and methacrylic acid are mixed in a predetermined ratio, and THF is added.
Dissolved in THF and added to the resulting THF solution as A as a polymerization initiator.
A copolymer represented by the following chemical formula was obtained by adding IBN and reacting at 60 ° C. for 5 hours.

[0239]

[Chemical 101] (Polymer (PI-38)) Monomer (I-13), methacrylic acid, and methacrylic acid methacrylate are mixed in a predetermined ratio and dissolved in THF, and AIBN as a polymerization initiator is added to the obtained THF solution. 25 at 60 ℃
By reacting for a time, a copolymer represented by the following chemical formula was obtained.

[0240]

[Chemical 102] (Polymer (PI-39)) Monomer (I-14) and methacrylic acid are mixed at a predetermined ratio and dissolved in THF,
AIBN as a polymerization initiator was added to the obtained THF solution and reacted at 60 ° C. for 25 hours to obtain a copolymer represented by the following chemical formula.

[0241]

[Chemical 103] (Polymer (PI-40)) Monomer (I-15) 0.
060 mol, t-butyl methacrylate 0.040 m
ol, and 0.0125 mol of AIBN in THF 3
It was dissolved in 0 g, and the resulting THF solution (reaction solution) was freeze-deaerated three times at a liquid nitrogen temperature under an argon atmosphere.
Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and further THF was added.
Was added. While stirring 500 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to synthesize a copolymer. The yield of the obtained polymer was 7.3 g, and the weight average molecular weight was 13,000 in terms of polystyrene.

[0242]

[Chemical 104] (Polymer (PI-41)) Monomer (I-16) 0.
064 mol, tetrahydromethacrylate 0.036
mol, and 0.0125 mol of AIBN in THF
After dissolving in 30 g, the resulting THF solution (reaction solution) was freeze-deaerated 3 times at a liquid nitrogen temperature under an argon atmosphere. Then, after reacting at 60 ° C. for 30 hours in an argon atmosphere, 2 ml of methanol was added to the reaction solution, and then T
30 g of HF was added. While stirring 500 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, the solid content is 3 at 60 ° C.
It was vacuum dried for a day to synthesize a copolymer. The yield of the obtained polymer was 7.3 g, and the weight average molecular weight was 13,000 in terms of polystyrene.

[0243]

[Chemical 105] (Polymer (PI-42)) Monomer (I-17) 0.
055 mol, t-butyl methacrylate 0.045 m
ol, and 0.0125 mol of AIBN in THF 3
It was dissolved in 0 g, and the resulting THF solution (reaction solution) was freeze-deaerated three times at a liquid nitrogen temperature under an argon atmosphere.
Then, after reacting at 60 ° C. for 30 hours under an argon atmosphere, 2 ml of methanol was added to the reaction solution, and further THF was added.
Was added. While stirring 500 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, the solid content was vacuum dried at 60 ° C. for 3 days to synthesize a copolymer. The yield of the obtained polymer was 7.0 g, and the weight average molecular weight was 14,000 in terms of polystyrene.

[0244]

[Chemical formula 106] (Polymer (PI-43)) Vinyl naphthalene 1.0
g, lithocholic acid 2.4 g, methacrylic acid anhydride 1 g,
And 0.6388 g of AIBN were dissolved in 30 g of THF and reacted at 60 ° C. for 40 hours, 10 g of THF in which 1 g of water was dissolved was added, and the reaction was further performed for 8 hours. The insoluble material was filtered, the reaction solution was added dropwise to stirred water, and the deposited precipitate was vacuum dried to obtain a copolymer represented by the following chemical formula. The molecular weight of the obtained polymer was 50,000 in terms of polystyrene.

[0245]

[Chemical formula 107] (Polymer (PI-44)) Vinyl naphthalene 0.02
5 mol, 2-methacryl oil oxyadamantyl hexahydrophthalate 0.045 mol, t-butoxycarbonyl 2-methacryl oil oxyadamantyl 0.
030 mol and AIBN 0.0125 mol were melt | dissolved in THF 30g, and the obtained THF solution (reaction liquid) was freeze-deaerated 3 times at liquid nitrogen temperature under argon atmosphere. Then, at 60 ° C. under an argon atmosphere for 30
After reacting for 2 hours, add 2 ml of methanol to the reaction mixture,
Further, 30 g of THF was added. While stirring 500 g of hexane, the reaction solution was dropped one drop at a time for reprecipitation and then filtered through a glass filter. Finally, add 6
It was vacuum dried at 0 ° C. for 3 days to synthesize a copolymer represented by the following chemical formula. The weight average molecular weight of the obtained polymer was 11,000 in terms of polystyrene.

[0246]

[Chemical 108] (Comparative polymer (CI-1)) γ-((1-methyl) cyclopentyl) methacrylate was polymerized by the same procedure as in the synthesis of the polymer (PI-3) described above except that 10.1 g of cyclohexylmethacrylate was changed. A polymer was obtained. The yield was 10.85 g, and the weight average molecular weight was 15,000 in terms of polystyrene. The polymer obtained here is the same as the above-mentioned polymer (PI-4) except that it is not a tertiary alcohol ester. (Comparative polymer (CI-2)) isobornyl methacrylate,
Methacrylic acid t-Bu and methacrylic acid were mixed at a predetermined ratio, dissolved in THF, and AIBN as a polymerization initiator was added to the obtained THF solution and reacted at 60 ° C. for 30 hours to obtain the following chemical formula: A high molecular polymer represented by

[0247]

[Chemical 109] First, of the polymers obtained as described above, the following photoacid generators were added to the polymers (PI-1) to (PI-11) and the comparative polymer (CI-1), respectively. Exposure experiment was performed.

The abbreviations of the photo-acid generator used here are summarized below.

TPS / OTf: triphenylsulfonium trifluoromethanesulfonic acid DPI / OTf: diphenyliodonium trifluoromethanesulfonic acid DNI / OTf: dinaphthyliodonium trifluoromethanesulfonic acid S-TFDT / OTf: S- (trifluoromethyl) dibenzothio Phenium trifluoromethanesulfonic acid Se-TFDT.OTf: Se- (trifluoromethyl) dibenzothiophenium trifluoromethanesulfonic acid I-DBT.OTf: I-dibenzothiophenium trifluoromethanesulfonic acid (Example I-1) To the polymer (PI-1) 1.0 g, each of the 6 types of photo-acid generators shown below is 0.05
g and dissolved in 4.2 g of cyclohexanone to obtain a solution of the photosensitive composition.

The obtained solution was spin coated to 3
It was spin-coated on a silicon wafer at 000 rpm for 30 seconds. Then, on a hot plate at 110 ° C for 10
A pre-exposure bake was performed for 0 seconds to form a resist film having a film thickness of 0.5 μm. ArF is applied to a predetermined area of the resist film.
The line and space was patterned by irradiating an excimer laser beam (wavelength 193 nm) and performing an exposure process. Then, the resist film after exposure is exposed to 10
After post-exposure bake at 0 ° C. for 180 seconds,
It was developed in a 4N aqueous solution of tetramethylammonium hydroxide at 25 ° C. for 60 seconds. As a result, the exposed portion of the resist film was selectively dissolved and removed to form a positive pattern.

The sensitivity of ArF excimer laser light here and the resolution of the obtained pattern are summarized in Table 1 below together with the photo-acid generator blended.

[0252]

[Table 1] From the results in Table 1, it is understood that the photosensitive composition of the present invention can form a line and space having a line width of 0.35 μm regardless of the photo-acid generator. Especially, as a photo-acid generator, D
When PI / OTf is blended, a fine pattern having a line width of 0.25 μm can be formed with a dose of 26 mJ / cm ² . (Example I-2) The polymer (PI-2) 1.0 g was mixed with 0.05 of each of the 6 types of photo-acid generators shown below.
g and dissolved in 4.2 g of cyclohexanone to obtain a solution of the photosensitive composition.

Using the obtained solution, the above-mentioned Example (I
When a pattern was formed according to the same procedure as in -1), the exposed portion of the resist film was dissolved and removed, and a positive pattern was formed. The sensitivity of the ArF excimer laser light here and the resolution of the obtained pattern are
It is summarized in Table 2 below together with the blended photo-acid generator.

[0254]

[Table 2] From the results of Table 2, it is understood that the photosensitive composition of the present invention can form a line and space having a line width of 0.35 μm regardless of the photo-acid generator. Especially, as a photo-acid generator, D
When PI / OTf is blended, a fine pattern with a line width of 0.25 μm can be formed with a dose of 24 mJ / cm ² . (Example I-3) The polymer (PI-3) (1.0 g) was mixed with 0.01 of each of the six photoacid generators shown below.
5 g was added and dissolved in 4.2 g of cyclohexanone to obtain a solution of the photosensitive composition.

Using the obtained solution, a developing solution of 0.028
A pattern was formed according to the same procedure as in Example (I-1) described above, except that the aqueous solution of N-tetramethylammonium hydroxide was used. As a result, the exposed portion of the resist film was dissolved and removed to form a positive pattern. The sensitivity of ArF excimer laser light here and the resolution of the obtained pattern are summarized in Table 3 below together with the photoacid generator compounded.

[0256]

[Table 3] From the results of Table 3, it is understood that the photosensitive composition of the present invention can form a line and space having a line width of 0.40 μm regardless of the photo-acid generator. Especially, as a photo-acid generator, D
When NI.OTf is blended, a fine pattern having a line width of 0.35 μm can be formed with a dose of 23 mJ / cm ² . (Example I-4) The polymer (PI-4) (1.0 g) was mixed with 0.01 parts of each of the six photoacid generators shown below.
5 g was added and dissolved in 4.2 g of cyclohexanone to obtain a solution of the photosensitive composition.

Using the obtained solution, the above-mentioned Example (I
When a pattern was formed according to the same procedure as in (3), the exposed portion of the resist film was dissolved and removed to form a positive pattern. The sensitivity of the ArF excimer laser light here and the resolution of the obtained pattern are
It is summarized in Table 4 below together with the blended photo-acid generator.

[0258]

[Table 4] From the results in Table 4, it is understood that the photosensitive composition of the present invention can form a line and space having a line width of 0.35 μm regardless of the photoacid generator. Especially, as a photo-acid generator, D
When PI / OTf is blended, a fine pattern having a line width of 0.25 μm can be formed with a dose of 26 mJ / cm ² . (Example I-5) Polymers (PI-5) to (PI-1)
1) TPS / OT as a photo-acid generator against 1.0 g
0.015 g of each of f and cyclohexanone 4.
It was dissolved in 2 g to obtain a solution of the photosensitive composition.

Using the obtained solution, the above-mentioned Example (I
When a pattern was formed according to the same procedure as in (3), the exposed portion of the resist film was dissolved and removed to form a positive pattern. The sensitivity of the ArF excimer laser light here and the resolution of the obtained pattern are
The resins used are summarized in Table 5 below.

[0260]

[Table 5] From the results in Table 5, it can be seen that each of the photosensitive compositions of the present invention can form a line and space having a line width of 0.30 μm. Particularly, when the polymer (PI-10) was used, the line width was 0.20 at an irradiation dose of 22 mJ / cm ^2.
A fine pattern of μm can be formed. (Example I-6) Polymers (PI-5) to (PI-1)
1) To 0.8 g, 0.2 g of a compound represented by the following chemical formula as a dissolution inhibitor, and T as a photoacid generator
0.015 g of PS.OTf was added and dissolved in 4.2 g of ethyl lactate to obtain a solution of a photosensitive composition.

[0261]

[Chemical 110] In the formula, -R is selected from the group shown below.

[0262]

[Chemical 111] When a pattern was formed using the obtained solution according to the same procedure as in Example (I-3) described above, the exposed portion of the resist film was dissolved and removed to form a positive pattern. The sensitivity of the ArF excimer laser light here and the resolution of the obtained pattern are summarized in Table 6 below together with the resin used.

[0263]

[Table 6] From the results in Table 6, it can be seen that each of the photosensitive compositions of the present invention can form a line and space having a line width of 0.30 μm. In particular, when the polymer (PI-10) was used, the line width was 0.20 at an irradiation dose of 20 mJ / cm ^2.
A fine pattern of μm can be formed. (Example I-7) Polymers (PI-12) to (PI-3)
4) 1.0g against TPS / OT as a photo-acid generator
0.015 g of each of f was added and dissolved in 4.2 g of propylene glycol monomethyl ether acetate to obtain a solution of a photosensitive composition.

Using the obtained solution, the above-mentioned Example (I
When a pattern was formed according to the same procedure as in (3), the exposed portion of the resist film was dissolved and removed to form a positive pattern. The sensitivity of the ArF excimer laser light here and the resolution of the obtained pattern are
The resins used are summarized in Table 7 below.

[0265]

[Table 7] From the results in Table 7, it can be seen that each of the photosensitive compositions of the present invention can form a line and space having a line width of 0.32 μm. Particularly, when the polymer (PI-15) was used, the line width was 0.18 at an irradiation dose of 14 mJ / cm ^2.
A fine pattern of μm can be formed. (Example I-8) Polymers (PI-40) to (PI-4)
4) TPS / O as a photo-acid generator against 1.5 g
0.015 g of each Tf was added and dissolved in propylene glycol monomethyl ether acetate, and the total amount was adjusted to 10 g to obtain a solution of a photosensitive composition. Filter this, 3000 rpm on 8 inch silicon wafer
Was spin coated and dried at 120 ° C. for 90 seconds to form a resist film.

An ArF exposure device N is applied to this resist film.
A = 0.55 exposure and post exposure bake (PI-40)
Was performed at 110 ° C. for 90 seconds, and otherwise at 140 ° C. for 60 seconds. The resist film after baking was developed with a tetramethylammonium hydroxide solution, and the exposed part was selectively dissolved and removed to obtain a positive pattern.

The sensitivity of the ArF excimer laser light here and the resolution of the obtained pattern are summarized in Table 8 below together with the resin used.

[0268]

[Table 8] From the results in Table 8, it can be seen that each of the photosensitive compositions of the present invention can form a line and space having a line width of 0.20 μm. In particular, when the polymer (PI-41) was used, the line width was 0.18 at an irradiation dose of 11 mJ / cm ^2.
A fine pattern of μm can be formed. (Comparative Example I-1) To 0.1 g of the comparative polymer (CI-1), 0.015 g of triphenylsulfonium trifluoromethanesulfonic acid as a photo-acid generator was added and dissolved in 4.2 g of cyclohexanone for comparison. A solution of the example photosensitive composition was obtained. The solution prepared here is the same as that used in the above-mentioned Example (I-4), except that the resin was not a tertiary alcohol ester.

Using the obtained solution, the above-mentioned Example (I-
An attempt was made to form a pattern according to the same procedure as 3), but resolution could not be achieved.

Further, a similar sample was spin coated on a silicon wafer at 3000 rpm for 30 seconds by spin coating. Then, heat treatment was performed on a hot plate at 120 ° C. for 90 seconds to form a resist film. After irradiating the resist film with a mercury lamp to generate an acid from the photo-acid generator, the resist film was scraped off with a razor. This sample is 5 ° C./min by thermogravimetric measurement (TG)
As a result of raising the temperature at, a weight loss was shown from around 180 ° C.
From this experiment, it was confirmed that esters of non-tertiary alcohols do not function as dissolution inhibiting groups because they are not easily decomposed by the catalytic action of acid. (Evaluation of dry etching resistance) t-Butyl and methacrylic acid were copolymerized at a molar ratio of 1: 1 to obtain a copolymer. A photosensitive composition was prepared using this copolymer as a reference, and the photosensitive composition of the present invention and dry etching resistance were compared. Here, the above-mentioned polymer (PI
Using -1) to (PI-11), a resist film was formed on the silicon wafer in the same manner as described above. CF ₄ was added to the obtained resist film at 30 sccm and 0.01 t
Reactive ion etching (RIE) was performed at orrm 150 W / 20 W, and the obtained etch rates are summarized in Table 9 below.

[0271]

[Table 9] As shown in Table 9, the reference photosensitive composition containing a polymer having no alicyclic compound has poor dry etching resistance. On the other hand, since the photosensitive composition of the present invention contains a high molecular weight polymer containing an alicyclic compound, it can be seen that each of them has high dry etching resistance. (Example I-9) Polymers (PI-36) to (PI-3)
9) and the comparative polymer (CI-2) were blended with predetermined components according to the formulation shown in Table 10 below and dissolved in methoxypropionic acid methyl ester to prepare a photosensitive composition solution.

[0272]

[Table 10] The photo-acid generator and the dissolution inhibitor shown in Table 10 above are
The abbreviations are shown below.

[0273]

[Chemical 112] Then, each of these photosensitive compositions was spin-coated on a silicon wafer to form a resist film having a thickness of 0.5 μm. For the obtained resist film, A with a wavelength of 193 nm was used.
The pattern was exposed by irradiating a predetermined region of the resist film with light using a stepper with NA 0.54 using rF excimer laser light as a light source. Then, after the exposed resist film is baked under the conditions shown in Table 8 below,
Tetrahydroammonium hydroxide aqueous solution (TMA
H) was developed. As a result, the exposed portion of the resist film was selectively dissolved and removed to form a positive resist pattern. The resist sensitivity and resolution at this time are also shown in Table 11 below.

[0274]

[Table 11] As shown in Table 11, polymers (PI-36) to (PI-36)
In each of the resists containing -39), peeling or swelling due to lack of adhesion or unevenness at the time of development was not found with high sensitivity, and a resist pattern having good resolution could be formed. On the other hand, a comparative polymer (CI-
The resist containing 2) was peeled off due to insufficient resist adhesion, and a fine pattern could not be formed. Further, the uniformity of dissolution of the resist film was poor, and partial peeling and cracks occurred.

Furthermore, regarding these resists, CF
_{4 The} etching rate by plasma was measured. As a result, when the etching rate of the resist based on novolac resin is set to 1.0, the comparative polymer (CI-2)
The etching rate of the resist compounded with was 1.3, whereas the etching rate of the resist compounded with the polymers (PI-36) to (PI-39) was 1.1 to 1.3. From these results, it was confirmed that each of the photosensitive compositions of the present invention has high etching resistance. (Example II) In this example, a photosensitive composition was prepared using the high molecular polymer represented by the general formula (6), and its characteristics were examined. (Synthesis of high molecular weight polymer) 3.4-Dihydro-2H-pyran and 4-pentenoic acid were mixed with tetrahydrofuran (T
Tetrahydropyranyl 4-pentenoic acid (THP-PA) was synthesized by dissolving it in equimolar amount in HF) and reacting it under a slight amount of a basic catalyst. This THP-PA,
Isobornyl acrylate and 4-pentenoic acid were dissolved in THF at a molar ratio of 40:30:30, 2 parts by weight of AIBN was added as a polymerization initiator, and the mixture was heated at 70 ° C. for 30 hours to obtain a polymer copolymer IH. -I got IT.

6-Heptenoic acid tetrahydropyranyl (THP-HA) was synthesized in the same manner as described above except that 4-pentenoic acid was changed to 6-heptenoic acid. The THP-HA, isobornyl acrylate and 6-heptenoic acid were dissolved in THF at a molar ratio of 40:30:30, 2 parts by weight of AIBN was added as a polymerization initiator, and the mixture was heated at 70 ° C. for 30 hours, A high molecular weight copolymer IP-PT was obtained.

A t-Bu group or an ethoxyethyl group was introduced as a dissolution inhibitor, and a compound containing norbornyl, adamantyl or menthyl was used as an alicyclic compound to obtain a high molecular copolymer.

The chemical formula of the high molecular weight copolymer obtained as described above is shown below together with the average molecular weight thereof.

[0279]

[Chemical 113]

[0280]

[Chemical 114] Further, in the general formula (6), R ⁵⁵ and a polymer having R ⁵⁵ as an organic group having 1 carbon atom and a polymer having R ⁵⁷ as an alicyclic organic group are prepared as follows. Synthesized. (Synthesis of high-molecular polymer in which R ⁵⁵ and R ⁵⁶ are organic groups having 1 carbon atom) Tetrahydropyranyl vinyl acetate (THP-VA) in the same manner as described above except that 4-pentenoic acid is changed to vinyl acetic acid. Was synthesized. This THP-V
A, isobornyl acrylate and vinyl acetic acid 4
The polymer was dissolved in THF at a molar ratio of 0:30:30, 2 parts by weight of AIBN as a polymerization initiator was added, and the mixture was heated at 70 ° C. for 30 hours and then the polymer copolymer represented by the following chemical formula (IP- VT) was obtained.

[0281]

[Chemical 115] (Synthesis of high molecular polymer in which R ⁵⁷ is an alicyclic organic group) 4-
4-Pentenoic acid chloride is synthesized by reacting pentenoic acid with thionyl chloride, and further reacted with 2-methyl-2-adamantanol in the presence of triethylamine to give 4-pentenoic acid (2-methyl-2- Adamantyl) (MAD-PA) was obtained. 4-
Pentenoic acid and MAD-PA were dissolved in THF at a molar ratio of 30:70, 2 parts by weight of AIBN was added as a polymerization initiator, and the mixture was heated at 70 ° C. for 30 hours to give a polymer copolymer represented by the following chemical formula. A combination (MA-PA) was obtained.

[0282]

[Chemical formula 116] (Synthesis of Comparative Polymer) A copolymer polymer using methacrylic acid as an acidic group and methacrylic acid t-Bu as a dissolution inhibiting group was synthesized in the same manner as described above. The chemical formula of the obtained copolymer is shown below.

[0283]

[Chemical 117] (Preparation of resist and formation of resist pattern) The copolymer, the dissolution inhibitor, and the photo-acid generator synthesized as described above were dissolved in cyclohexanone according to the formulation shown in Table 12 below, and the results of Example (II-1 ) ~ (II-1
A varnish of the photosensitive composition of 2) was prepared. In addition, as a photo-acid generator, Midori Chemical Co., Ltd. NAT-105 or ND
S-105 was used. On the other hand, a comparative polymer (IM-M
B, IM-MT), NAT-1 as a photoacid generator
No. 05 was blended to prepare varnishes of the photosensitive compositions of Comparative Examples (II-1) and (II-2).

[0284]

[Table 12] In Table 12, tBocBN, tBocNN and tBuC
Each O represents a compound represented by the following chemical formula.

[0285]

[Chemical 118] Then, varnishes of these photosensitive compositions were spin-coated on a silicon wafer to form a resist film having a thickness of 0.6 μm. A predetermined area of the obtained resist film was irradiated with N using ArF excimer laser light having a wavelength of 193 nm as a light source.
The pattern light was exposed using an A0.54 stepper.
Next, the exposed resist film was baked at 100 ° C. for 2 minutes and then developed with a predetermined developing solution. Here, as the developing solution, a tetrahydroammonium hydroxide aqueous solution (TMAH) or TMAH is used.
And a mixed solution of isopropyl alcohol was used. As a result, the exposed portion of the resist film was selectively dissolved and removed to form a positive resist pattern. Peeling of the obtained resist pattern from the substrate and uniformity of dissolution were examined, and the results are shown in Table 13 below together with the sensitivity.

[0286]

[Table 13] As shown in Table 13, the present invention (Examples II-1 to II-1)
In the resists of 2), phenomena such as lack of adhesion during development and peeling or swelling due to non-uniform dissolution were not found with high sensitivity, and a resist pattern with good resolution was obtained. Specifically, Examples (II-8) and (II-
In 9), the appearance of the obtained pattern was good and there were no problems, and Examples (II-1) to (II-5) and (II-7) were used.
In and (II-10), some peeling was observed in the ultrafine pattern. Further, in Examples (II-6), (II-11) and (II-12), some cracks were generated.

On the other hand, Comparative Examples (II-1) and (II-2)
In the resist of (1), pattern peeling occurred due to lack of resist adhesion, and a fine pattern could not be formed. Further, the uniformity of dissolution of the resist film was poor, and partial peeling cracks occurred.

Thus, it can be seen that the second photosensitive composition has transparency to short wavelength light and high dry etching resistance. Therefore, by using such a photosensitive composition, peeling during development with an alkaline solution and uneven dissolution can be suppressed, and a good resist pattern can be formed. (Example III) In this example, a photosensitive composition was prepared using a polymer having a repeating unit represented by any of the general formulas (7) to (9), and its characteristics were examined.

First, the high molecular weight polymers (PP-1) to (PP-12) used in this example were synthesized as follows. (Synthesis Example III-1) First, α-chloroacrylic acid and isoborneol were reacted under a hydrochloric acid catalyst to obtain an ester. This ester, tetrahydropyranyl methacrylate, and methacrylic acid were mixed at a predetermined ratio and dissolved in THP to prepare a THF solution. Add AIBN as a polymerization initiator to the obtained THP solution, and
By reacting at 0 ° C. for 3 hours, the following chemical formula (PP
A polymer copolymer represented by -1) was obtained.

[0290]

[Chemical formula 119] (Synthesis Example III-2) First, an acetal was obtained by reacting α-chloroacrylic acid with dihydropyran under a hydrochloric acid catalyst. This acetal, menthyl methacrylate, and methacrylic acid are mixed in a predetermined ratio to prepare THP.
To prepare a THF solution. AIBN as a polymerization initiator was added to the obtained THP solution at 60 ° C. for 30 minutes.
By reacting for a time, a polymer copolymer represented by the following chemical formula (PP-2) was obtained.

[0291]

[Chemical 120] (Synthesis Example III-3) First, monochloromaleic anhydride was dissolved in THF, and an equimolar amount of menthol was added to the solution.
Reflux for hours. The product was separated and purified by a silica gel column to obtain monomenthyl chloromaleic acid.

By blending this monomenthyl chloromaleic acid and tetrahydropyranyl methacrylate at a predetermined ratio and polymerizing with AIBN as a polymerization initiator, a polymer copolymer represented by the following chemical formula (PP-3) Got united.

[0293]

[Chemical 121] (Synthesis Example III-4) Monochloromaleic anhydride, adamantyl methacrylate, and t-Bu methacrylate are blended at a predetermined ratio and polymerized in the presence of AIBN, which is represented by the following chemical formula (PP-4). A high molecular weight copolymer was obtained.

[0294]

[Chemical formula 122] (Synthesis Example III-5) First, dichloromaleic anhydride was dissolved in THF, equimolar menthol was added, and the mixture was refluxed for 3 hours. The product was separated and purified by a silica gel column to obtain monomenthyl dichloromaleic acid.

With this monomenthyl dichloromaleic acid,
Tetrahydropyranyl methacrylate was blended at a predetermined ratio and polymerized in the presence of AIBN to obtain a polymer copolymer represented by the following chemical formula (PP-5).

[0296]

[Chemical 123] (Synthesis Example III-6) First, dihydropyran and dichloromaleic acid were reacted in THF to obtain monotetrahydropyranyl dichloromaleate.

This monotetrahydropyranyl dichloromaleate and isobornyl methacrylate were mixed in a predetermined ratio and polymerized in the presence of AIBN to obtain a polymer copolymer represented by the following chemical formula (PP-6). It was

[0298]

[Chemical formula 124] (Synthesis Example III-7) Dichloromaleic anhydride, isobornyl methacrylate, and tetrahydropyranyl methacrylate are mixed in a predetermined ratio and polymerized in the presence of AIBN, which is represented by the following chemical formula (PP-7). A high molecular weight copolymer was obtained.

[0299]

[Chemical 125] (Synthesis Example III-8) First, dichloromaleic anhydride and tetrahydropyranyl methacrylate were copolymerized at a ratio of 1: 1 to obtain a copolymer, which was used as a THF solution. Next, menthol was added to this THF solution at a ratio of 80 mol% of dichloromaleic anhydride, and the mixture was stirred for one day to obtain a polymer copolymer represented by the following chemical formula (PP-8).

[0300]

[Chemical formula 126] (Comparative Example III-1) Tetrahydropyranyl methacrylate, menthyl methacrylate, and methacrylic acid were blended in a desired ratio and polymerized in the presence of AIBN to obtain a polymer represented by the following chemical formula (PP-11). A polymer was obtained.

[0301]

[Chemical 127] (Comparative Example III-2) Maleic anhydride, isobornyl methacrylate, and tetrahydropyranyl methacrylate were mixed at a predetermined ratio and polymerized in the presence of AIBN to obtain a polymer represented by the following chemical formula (PP-12). A molecular copolymer was obtained.

[0302]

[Chemical 128] (Preparation of resist and formation of resist pattern) A photo-acid generator and a dissolution inhibitor were added to the polymer copolymer synthesized as described above in a formulation shown in Table 14 below to dissolve in cyclohexanone. Examples (III-1) to (I
II-12), and Comparative Examples (III-1), (III-2)
Got the resist.

[0303]

[Table 14] The photo-acid generator and the dissolution inhibitor shown in Table 14 above are
The abbreviations are shown below.

[0304]

[Chemical formula 129]

[0305]

[Chemical 130] Next, each of these photosensitive compositions was spin-coated on a silicon wafer to form a resist film having a thickness of 0.6 μm. Next, an electron beam drawing device with an acceleration voltage of 50 keV,
Alternatively, a predetermined pattern was exposed on the surface of the resist film by using a stepper with NA 0.54 using ArF excimer laser light having a wavelength of 193 nm as a light source.

The resist film after exposure is exposed to 120 ° C. for 2 hours.
After a baking treatment for 1 minute, it was developed with an aqueous solution of tetrahydroammonium hydroxide (TMAH). As a result, the exposed portion of the resist film was selectively dissolved and removed to form a positive resist pattern. In addition,
With respect to the photosensitive composition of Comparative Example (III-2), a pattern was formed using two kinds of ArF excimer laser and electron beam as exposure light.

The sensitivity and resolution of each resist were evaluated by CF ₄
Table 15 together with the dry etching resistance by Incidentally, the dry etching resistance is shown in the comparative example (III-
It was expressed as a relative value with 1) set to 1.0.

For comparison of dry etching resistance, EBR-9, which is a conventional poly (α-chloroacrylic acid ester), is shown in Table 15 as Comparative Example (III-3).

[0309]

[Table 15] As shown in Table 15, the present invention (Examples III-1 to III-
Each of the resists of 12) is excellent in sensitivity and resolution, and more excellent in etching resistance than conventional α-chloroacrylic acid ester polymers.

As described above, the photosensitive composition of this example has high sensitivity and high resolution with respect to irradiation with actinic radiation. By using such a photosensitive composition, a resist pattern having sufficient dry etching resistance can be formed by alkali development.

[0311]

As described in detail above, according to the present invention,
Provided is a photosensitive composition capable of forming a resist pattern having excellent transparency to ultrashort wavelength light such as ArF excimer laser light, high sensitivity and high resolution, and having excellent dry etching resistance. Such a photosensitive composition,
It is effective as a resist for microfabrication in the manufacturing process of electronic parts and has great industrial value.

[Brief description of drawings]

FIG. 1 is a cross-sectional view schematically showing a part of a manufacturing process of an electronic component using the photosensitive composition of the present invention.

FIG. 2 is an infrared spectroscopy spectrum diagram of an example of a high-molecular polymer contained in the photosensitive composition of the present invention.

[Explanation of symbols]

11 ... Silicon wafer 13 ... Resist film 14 ... Exposure light 16 ... Exposure unit 17 ... Resist pattern 18 ... Patterned silicon wafer

Front page continuation (72) Inventor Toru Gokawachi 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Toshiba Research & Development Center, Inc. (72) Inventor Takeshi Okino 1 Komukai-shiba, Saiwai-ku, Kawasaki-shi, Kanagawa Toshiba Research & Development Center (72) Inventor Shin Nakase 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Prefecture Toshiba Research & Development Center (72) Inventor Takuya Naito Komukai-Toshiba, Kawasaki-shi, Kanagawa No. 1 Toshiba Research & Development Center Co., Ltd. (72) Inventor Satoshi Saito No. 1 Komukai Toshiba Town, Komukai-shi, Kawasaki City, Kanagawa Prefecture Toshiba Research & Development Center Co., Ltd. (56) Reference JP-A-8-82925 (JP, A) ) JP-A-8-123031 (JP, A) JP-A-9-73173 (JP, A) JP-A-8-259626 (JP, A) JP-A-8-254828 (JP, A) JP-A-8- 137107 (JP, A) JP-A-8-101508 (JP, A) JP-A-10-171122 (JP, A) JP-A-9-221519 JP, A) JP flat 10-239847 (JP, A) (58 ) investigated the field (Int.Cl. ^7, DB name) G03F 7/00 - 7/42

Claims (11)

(57) [Claims] 1. A photosensitive composition comprising a high molecular polymer having a repeating unit represented by the following general formula (1A) and a compound capable of generating an acid upon irradiation with actinic radiation. [Chemical 1] (In the general formula (1A), R ¹¹ represents a hydrogen atom or methyl.
A group, a halogen atom or a cyano group, R ¹² is methyl.
And R ¹³ is a) a linear aliphatic group having 2 to 12 carbon atoms; a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, and a bridging hydrocarbon introduced therein. Cyclic group selected from the group consisting of a steroid, a spiro ring, a terpene ring, a steroid, a tanjusan, a digitalloid ring, a camphor ring, an isocamphor ring, a sesquiterpene ring, a sandton ring, a diterpene ring, a triterpene ring, and a steroid saponin. ; and _{b) - (CH 2) m} - (m is one of the hydrocarbon groups represented by 3 to 9 which is an integer). R ¹⁴ is a hydrophilic group. ) 2. Repetition represented by the following general formula (2):
A unit and a repeating unit represented by the following general formula (3)
A photosensitive composition containing a high molecular weight polymer containing at least one group and a compound capable of generating an acid upon irradiation with actinic radiation. [Chemical 2] (In the general formula (2), R ²¹ represents a hydrogen atom, a methyl group,
A halogen atom or a cyano group, R ²² is a methyl group
Is. R ²³ , R ²⁴ , R ²⁵ and R ²⁶ may be the same or different.
Each may have a hydrogen atom or a carbon number of 6 or less
Is a hydrocarbon group. ) [Chemical 3] (In the general formula (3), R ³¹ represents a hydrogen atom, a methyl group,
A halogen atom or a cyano group, R ³² is a methyl group
Is. When less of ^{R 33, R 34, R 35} , R 36 and R ³⁷
One is a hydrocarbon group having 6 or less carbon atoms, and the other is the same.
May be one or different, and may be a hydrogen atom, a methyl group, a halo
Selected from the group consisting of a gen atom and a cyano group.
It ) 3. Repetition represented by the following general formula (4):
A photosensitive composition comprising a high molecular polymer having units and a compound capable of generating an acid upon irradiation with actinic radiation. [Chemical 4] (In the general formula (4), R ⁴¹ represents a hydrogen atom, a methyl group,
A halogen atom or a cyano group, R ⁴⁴ is
Tan ring, cyclooctane ring, bridge hydrocarbons
Introduced, spiro ring, terpene ring, steroid,
Tanjusan, digitaloid ring, camphor ring, iso
Camphor ring, sesquiterpene ring, sandton ring, ditel
Pen ring, triterpene ring, and steroid saponins
R ⁴⁵ is a hydrophilic group selected from the group consisting of
It is a base. ) 4. A compound further containing a compound having an aromatic ring,
The aromatic ring of the
Is contained in a component added separately.
The photosensitive composition described . 5. The aromatic ring is naphthalene or a derivative thereof.
The photosensitive composition according to claim 4, which is a body . 6. Decomposition by acid to show alkali solubility
Group having a functional group including a group and an alkali-soluble group
The photosensitive composition according to claim 2 or 3 containing a child polymer. 7. Repetition represented by the general formula (4)
The unit is a repeating unit represented by the following general formula (5).
The photosensitive composition according to one claim 3. [Chemical 5] (In the general formula (5), R ⁴⁶ represents a hydrogen atom, a methyl group,
It is a halogen atom or a cyano group. ) 8. The method according to any one of claims 1 to 7.
The photosensitive composition of the above is coated on a substrate, heated and dried to form a resin layer.
And a pattern exposure by irradiating light on a predetermined region of the resin layer.
The step of applying, the step of heat-treating the resin layer after the pattern exposure, and the step of developing the resin layer after the heat treatment with an alkali developing solution.
A method of forming a pattern, comprising: 9. The method according to any one of claims 1 to 7.
To form a resist film by applying the photosensitive composition of
And the pattern exposure by irradiating a predetermined area of the resist film with light.
The step of applying light and the development treatment of the resist film after the pattern exposure using an image liquid
Forming a resist pattern, and using the resist pattern as an etching mask to form a substrate.
A method of manufacturing an electronic component including a patterning step
Law. 10. A repeat represented by the following general formula (4):
By irradiation with actinic radiation
A photosensitive composition containing a phosphoric acid-generating compound
The step of applying on top and heating and drying to form a resin layer, and pattern exposure by irradiating light to a predetermined region of the resin layer.
The step of applying, the step of heat-treating the resin layer after the pattern exposure, and the step of developing the resin layer after the heat treatment with an alkali developing solution.
A method of forming a pattern, comprising: [Chemical 6] (In the general formula (4), R ⁴¹ represents a hydrogen atom, a methyl group,
A halogen atom or a cyano group, R ⁴⁴ is
Tan ring, cyclooctane ring, bridge hydrocarbons
Introduced, spiro ring, terpene ring, steroid,
Tanjusan, digitaloid ring, camphor ring, iso
Camphor ring, sesquiterpene ring, sandton ring, ditel
Pen ring, triterpene ring, and steroid saponins
R ⁴⁵ is a hydrophilic group selected from the group consisting of
It is a base. ) 11. Repetition represented by the following general formula (4):
By irradiation with actinic radiation
A photosensitive composition containing a phosphoric acid-generating compound
The step of applying the resist to form a resist film, and irradiating light to a predetermined region of the resist film to expose the pattern.
The step of applying light and the development treatment of the resist film after the pattern exposure using an image liquid
Forming a resist pattern, and using the resist pattern as an etching mask to form a substrate.
A method of manufacturing an electronic component including a patterning step
Law. [Chemical 7] (In the general formula (4), R ⁴¹ represents a hydrogen atom, a methyl group,
A halogen atom or a cyano group, R ⁴⁴ is
Tan ring, cyclooctane ring, bridge hydrocarbons
Introduced, spiro ring, terpene ring, steroid,
Tanjusan, digitaloid ring, camphor ring, iso
Camphor ring, sesquiterpene ring, sandton ring, ditel
Pen ring, triterpene ring, and steroid saponins
R ⁴⁵ is a hydrophilic group selected from the group consisting of
It is a base. )