JPH09152715A - Positive chemically amplifying photosensitive resin composition and production of resist image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive photosensitive resin compsn. having high sensitiv ity, high resolution and high heat resistance by incorporating a resin which is soluble in an alkali soln., a specified polyphenol compd., a compd. which produces acid by irradiation of active chemical rays, and a vinyl polymer having such groups on the side chains that increase solubility with an alkali soln. by acid catalyst reaction. SOLUTION: This resin compsn. consists of (a) a resin solubble in an alkali soln., (b) a polyphenol compd. expressed by formula I or formula II, (c) a compd. which produces acid by irradiation of active chemical rays, and (d) a vinyl polymer having such a group in the side chain that is decomposed by acid and increases solubility with an alkali soln. by acid catalyst reaction. In formula I, R<1> and R<2> are 1-4C alkyl groups, aryl groups, etc., f and g are 0, 1 or 2, and h and i are 1, 2 or 3. In formula II, R<5> and R<6> are 1-3C alkyl groups, j and k are 0, 1 or 2, and 1 and m are 1, 2 or 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive chemical amplification type photosensitive resin composition used for microfabrication of semiconductor devices and a method for producing a resist image, and more particularly to ultraviolet rays, far ultraviolet rays, X-rays and electron beams. An acid is generated in the pattern image forming area by the pattern irradiation of radiation such as, and the solubility of the exposed area and the unexposed area in the alkaline developer is changed by the reaction using the acid as a catalyst to reveal the pattern. The present invention relates to a positive chemically amplified photosensitive resin composition and a method for producing a resist image using the same.

[0002]

2. Description of the Related Art In recent years, the miniaturization of integrated circuits has been advanced in accordance with high integration, and in 64M or 256M DRAMs, pattern formation of sub-half micron or less has been required, and resist materials having excellent resolution have been developed. Requested. Conventionally, a reduction projection exposure apparatus has been used for producing an integrated circuit. At present, a pattern having an exposure wavelength or less can be resolved by devising a photomask or the like. However, a resolving power sufficient to support 64M or 256M DRAM has not been obtained.

On the other hand, exposure using X-rays or electron beams can be expected to achieve finer pattern processing than exposure using light. The minimum dimension of the pattern depends on the beam diameter, and a high resolution can be obtained. However, no matter how fine the exposure method is, the throughput of wafer processing becomes a problem from the viewpoint of mass production of LSI. As a method for improving the throughput, it is important to improve the sensitivity of the resist used, as well as to improve the apparatus.

As a resist material for achieving high sensitivity, for example, a composition containing a highly reactive medium in the presence of an acid catalyst and an acid precursor which generates an acid upon irradiation with actinic radiation is disclosed in US Pat. 3,779,778, JP-A-59-4
The compositions described in JP-A-5439 and JP-A-2-25850 are known. These known examples include compounds or polymers containing an acetal group as a highly reactive medium,
Compounds or polymers containing t-butyl groups are disclosed. Since these media contain an acid-decomposable group, they are converted into a compound or a polymer that changes the solubility in a developer by using an acid generated by irradiation with actinic radiation as a catalyst.

However, in the conventional resist material, the so-called γ value is lowered because the difference in the dissolution rate in the developing solution between the irradiated portion and the non-irradiated portion, which is necessary for obtaining a fine pattern with a good shape, becomes small. There was a problem of (decrease in resolution). When an alkali-soluble resin and a component that reacts under an acid catalyst are mixed and used, the heterogeneous two layers are separated, or the micro-layer separation forms a hardly soluble layer on the resist surface, which deteriorates the pattern shape. There was a very serious problem of doing so.

As described above, resist materials are desired to have high sensitivity and high resolution, but in addition, resistance to high temperature generated during dry etching, that is, high heat resistance is also desired. In a photosensitive resin composition containing a naaphthoquinonediazide compound as a photosensitive agent, improvement of an alkali-soluble resin has been attempted in order to achieve both high sensitivity, high resolution, and high heat resistance. For example, as an alkali-soluble resin, US Pat. No. 4,529,682 discloses o
-A novolak resin obtained by condensing a mixture of cresol, m-cresol and p-cresol with formaldehyde, in JP-A-60-158440, a mixture of m-cresol, p-cresol and 2,5-xylenol. A novolac resin obtained by condensing styrene with formaldehyde, and m-in JP-A-63-234249.
Novolak resins obtained by condensing a mixture of cresol, p-cresol and 3,5-xylenol with formaldehyde have been proposed, respectively. By limiting the synthesis raw material of the alkali aqueous solution-soluble resin as described above, a resist material having high sensitivity and high resolution could be provided. However, it was not possible to provide a highly heat resistant material.

It has also been proposed to improve the heat resistance of a resist material by improving the molecular weight of an alkali-soluble resin. For example, JP-A-64-14229 and JP-A-2-6
No. 0915 proposes to improve the heat resistance by removing the low molecular weight portion of the alkali-soluble resin. However, removal of the low molecular weight component of the alkali-soluble resin causes a decrease in sensitivity and resolution, and it has been difficult to provide a resist material having well-balanced properties.

In the case of a positive-working chemically amplified resist utilizing an acid-catalyzed reaction, attempts have been made to achieve both sensitivity, resolution and heat resistance by limiting the synthesis raw materials of the alkali-soluble resin or improving the molecular weight as described above. However, it has been difficult to provide a resist material having well-balanced properties.

[0009]

According to the first aspect of the present invention, an acid is generated in a pattern latent image forming portion by pattern-like irradiation of radiation such as ultraviolet rays, far ultraviolet rays, X-rays, and electron beams.
The acid-catalyzed reaction changes the solubility of the irradiated and unirradiated portions in an alkali developing solution, resulting in a high-sensitivity, high-resolution, positive-type chemically amplified photosensitive resin composition that makes a pattern appear. Another object of the present invention is to provide a positive-type chemically amplified photosensitive resin composition having high heat resistance. Claim 2
The invention in (1) provides a positive chemically amplified photosensitive resin composition having higher heat resistance in the first invention. The invention according to claim 3 provides a method for producing a resist image capable of revealing a resist pattern with good resolution.

[0010]

The present invention comprises (a) an alkali aqueous solution-soluble resin, (b) a general formula (I).

Embedded image (In the formula, R ¹ and R ² are each independently hydrogen and a carbon number of 1 to
4 represents an alkyl group, an aryl group or an aryl group having a phenolic hydroxyl group, R ³ and R ⁴ each independently represent an alkyl group having 1 to 3 carbon atoms, and f and g each independently represent 0, 1 or 2 And h and i are each independently 1, 2 or 3) or a polyphenol compound represented by the general formula (II)

Embedded image (In the formula, R ⁵ and R ⁶ each independently represent an alkyl group having 1 to 3 carbon atoms, j and k are each independently 0, 1 or 2, and 1 and m are each independently 1, 2 or Three
A polyphenol compound represented by the formula (1), (c) a compound which produces an acid upon irradiation with active actinic radiation, and (d) a vinyl polymer having a side chain with an acid-decomposable group whose solubility in an alkaline aqueous solution is increased by an acid-catalyzed reaction. The present invention relates to a positive-type chemically amplified photosensitive resin composition containing a combination.

The present invention also relates to the positive chemically amplified photosensitive resin composition, wherein the content of the low molecular weight component having a molecular weight of 2,000 or less in terms of polystyrene in the aqueous alkali-soluble resin is 10% by weight or less. The present invention also relates to a method for producing a resist image, which comprises irradiating a coating film of the positive type chemically amplified photosensitive resin composition with active actinic rays and then developing the resist image.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, as the alkali aqueous solution soluble resin used, for example, novolac resin, acrylic resin, copolymer of styrene and acrylic acid, polymer of hydroxystyrene, polyvinylphenol and the like can be mentioned. .

The alkali aqueous solution-soluble resin used in the present invention is preferably a novolak resin obtained by polycondensing phenols having one or more phenolic hydroxyl groups with aldehydes. For example, phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 3,4-xylenol, 3,5-xylenol,
Phenols having one phenolic hydroxyl group such as 2,3,5-trimethylphenol, phenols having two phenolic hydroxyl groups such as resorcinol and catechol, and phenolic hydroxyl groups such as phloroglucin, pyrogallol and hydroxyhydroquinone having three phenolic hydroxyl groups Phenols are mentioned. These phenols can be used alone or in combination of two or more. Aldehydes include, for example, formaldehyde, paraformaldehyde and the like. The amount of the aldehyde used is 0.5-1.
A range of 5 moles is preferred.

As a catalyst for the polycondensation, an acid catalyst capable of increasing the molecular weight is preferable. Examples of the acid catalyst include inorganic acids such as hydrochloric acid, nitric acid, and sulfuric acid, and organic acids such as formic acid, oxalic acid, and acetic acid. The amount of the acid catalyst used is preferably in the range of 1 × 10 ⁻⁵ to 1 × 10 ⁻¹ mol with respect to 1 mol of the phenols. The reaction temperature and reaction time for polycondensation are
The reaction temperature can be appropriately adjusted according to the reactivity of the synthesis raw materials, but usually the reaction temperature is 70 to 130 ° C., and the reaction time is 1 to 12 hours. Examples of the polycondensation method include a method in which phenols, aldehydes and a catalyst are charged all at once, and a method in which phenols and aldehydes are added in the presence of a catalyst as the reaction proceeds. After completion of the polycondensation, unreacted raw materials present in the reaction system,
To remove condensed water, catalyst, etc., under reduced pressure, for example, 2
The temperature in the reaction system is raised to 150 to 200 ° C. at 0 to 50 mmHg, and then the resin is recovered.

In the present invention, the alkali aqueous solution-soluble resin is particularly preferably one containing only 10% by weight or less (or 0%) of a low molecular weight component having a polystyrene reduced molecular weight of 2,000 or less. As a method for reducing or removing such low molecular weight components in the alkali aqueous solution-soluble resin, a dissolution fractionation method is generally used. That is, an aqueous alkali solution-soluble resin is dissolved in a good solvent such as acetone, ethyl cellosolve acetate, tetrahydrofuran, and methyl ethyl ketone to form a varnish, and the varnish is added to a poor solvent such as toluene, hexane, pentane, and xylene to obtain a low molecular weight. Reduction or removal of low molecular weight components is performed by dividing into a dilute phase having many components and a dense phase having many high molecular weight components, or by forming a precipitated phase having many high molecular weight components.

As disclosed in JP-A-64-14229, a resin soluble in an aqueous alkali solution is pulverized and dispersed in an aromatic solvent such as toluene or xylene to extract and reduce or remove low molecular weight components. You may go. Further, in the present invention, as shown in JP-A-2-222409, when synthesizing a resin, a good solvent and a poor solvent are mixed with the resin and a normal polycondensation synthesis reaction is performed to obtain a low molecular weight resin. You may use the method of obtaining the alkali aqueous solution soluble resin with few components. By such a method, the polystyrene-equivalent molecular weight of the aqueous alkali-soluble resin is 2,
The low molecular weight component of 000 or less can be in the range of 0 to 10% by weight. In the present invention, the molecular weight in terms of polystyrene is determined by gel permeation chromatography (GP).
It is measured by the method C) using standard polystyrene, and is determined by an area ratio to the whole having a molecular weight of 2,000 or less.

In the polyphenol compound (b) used in the present invention, ^one in which one or both of R ¹ and R ² in the general formula (I) is hydrogen is combined with another alkaline aqueous solution soluble resin to improve sensitivity and resolution. It is preferable because a particularly excellent positive photosensitive resin composition can be provided.
Further, either R ¹ or R ² may be an allyl group having a phenolic hydroxyl group.

Among the polyphenols represented by the general formula (I), the formulas (a) and (b) are

Embedded image Polyphenol compounds such as are preferably used, further,
Formula (c)

[Chemical 6] The polyphenol compounds of are preferred.

In the polyphenol compound represented by the general formula (II), the formula (d)

Embedded image The polyphenol compound of is preferably used.

These polyphenol compounds may be used alone or in combination of two or more. The compounding amount of the polyphenol compound is preferably 2 to 30 parts by weight, and particularly preferably 5 to 25 parts by weight, relative to 100 parts by weight of the (a) alkaline aqueous solution-soluble resin. If the amount of the polyphenol compound is too small, it is difficult to obtain a sufficient resolution, and if the amount is too large, it tends to be difficult to achieve both sensitivity and resolution.

Examples of the compound that produces an acid upon irradiation with active actinic radiation used in the present invention include onium salts, halogen-containing compounds, quinonediazide compounds, and sulfonic acid ester compounds. As the onium salt, for example,
Iodonium salts, sulfonium salts, phosphonium salts, ammonium salts, diazonium salts and the like can be mentioned, and preferably diaryl iodonium salts, triarylsulfonium salts, trialkylsulfonium salts (wherein the alkyl group has 1 to 4 carbon atoms), The counter anion of the onium salt includes, for example, tetrafluoroboric acid, hexafluoroantimonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid and toluenesulfonic acid. Examples of the halogen-containing compound include a haloalkyl group-containing hydrocarbon compound and a haloalkyl group-containing heterocyclic compound, and preferably include trichloromethyltriazine and bromoacetylbenzene. Examples of the quinonediazide compound include a diazobenzoquinone compound and a diazonaphthoquinone compound.

Examples of the sulfonic acid ester compound include an ester of an aromatic compound having a phenolic hydroxyl group and an alkylsulfonic acid or an aromatic sulfonic acid. For example, as an aromatic compound having a phenolic hydroxyl group. Is phenol, resorcinol, pyrogallo
Sulfonic acid, methanesulfonic acid, ethanesulfonic acid, propylsulfonic acid, butylsulfonic acid, and aromatic sulfonic acid such as phenylsulfonic acid and naphthylsulfonic acid. Acids and the like. An ester of an aromatic compound having a phenolic hydroxyl group with an alkylsulfonic acid can be synthesized by a usual esterification reaction. For example, an aromatic compound having a phenolic hydroxyl group can be reacted with an alkyl sulfonic acid or a chloride of an aromatic sulfonic acid under an alkaline catalyst. The synthetic product thus obtained can be purified by a recrystallization method or a reprecipitation method using an appropriate solvent.

From the viewpoint of providing sufficient sensitivity to active actinic radiation, the amount of the compound which produces an acid upon irradiation with active actinic radiation is set to 5 with respect to 100 parts by weight of the aqueous solution of alkali solution soluble.
It is preferably from 30 to 30 parts by weight, and further from 5 to 15 parts by weight.
It is preferably in parts by weight. If the amount of the compound that generates an acid by active actinic radiation is too large, the solubility in a solvent is reduced. If the amount is too small, sufficient sensitivity cannot be obtained.

Preferred as the vinyl polymer having an acid-decomposable group in the side chain (d) used in the present invention, the solubility of which in an alkaline aqueous solution is increased by an acid-catalyzed reaction,
This is a polymer in which the acid-decomposable group of the side chain is efficiently dissociated by an acid, and the solubility of the final product in an alkaline aqueous solution is significantly different from that of the polymer before dissociation. As such a polymer, an acrylic resin, a copolymer of styrene and acrylic acid, a polymer of hydroxystyrene, a phenolic hydroxyl group of an alkali aqueous solution-soluble resin such as polyvinylphenol, a hydrogen atom such as a carboxyl group is present in the presence of an acid. The compound substituted by the group which can dissociate below is mentioned.

Specific examples of the group capable of dissociating in the presence of an acid include methoxymethyl group, methoxyethoxymethyl group, tetrahydropyranyl group, tetrahydrofuranyl group, benzyloxymethyl group, 1-methoxyethyl group, 1-ethoxyethyl group, methoxybenzyl group, t-
Butyl group, methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group, trimethylsilyl group,
Examples thereof include triethylsilyl group and phenyldimethylsilyl group. Of these, a tetrahydropyranyl group, a tetrahydrofuranyl group, a t-butoxycarbonyl group, a 1-ethoxyethyl group, a triethylsilyl group and the like are preferable.

The rate of substitution of a phenolic hydroxyl group or a carboxyl group of a group capable of dissociating in the presence of an acid with hydrogen is preferably 15 to 100%, and further 3
Preferably it is 0 to 100%. The vinyl polymer having an acid-decomposable group need not have all of its hydroxyl groups protected with an acid-decomposable group. Regarding the molecular weight of the vinyl polymer having an acid-decomposable group, the weight average molecular weight (Mw) in terms of polystyrene determined by GPC is from 1,500 to 3,0.
00 is preferred. Polymers in this molecular weight range,
Since it has good compatibility with the resin soluble in the aqueous alkali solution, there is no formation of a layer hardly soluble in the aqueous alkali solution on the resist surface, and a high-resolution resist material is obtained.

(D) The amount of the vinyl polymer having an acid-decomposable group whose solubility in an alkaline aqueous solution is increased by the acid-catalyzed reaction is (a) the alkaline aqueous solution-soluble resin 10
It is preferably 5 to 30 parts by weight, and more preferably 5 to 20 parts by weight, relative to 0 parts by weight. The solubility in an alkaline aqueous solution is increased by an acid-catalyzed reaction. If the amount of the vinyl polymer having an acid-decomposable group added is too large, the irradiated part may be irradiated in a system in which the solubility in an alkaline aqueous solution increases by an acid-catalyzed reaction Tends to decrease the dissolution rate in a developing solution, and the resolution tends to decrease in a system in which the irradiated portion has reduced solubility in an aqueous alkali solution due to an acid catalyzed reaction. In addition, if the amount of the vinyl polymer having an acid-decomposable group whose solubility in an aqueous alkali solution is increased by an acid-catalyzed reaction is too small, the irradiation part may increase the solubility in an aqueous alkali solution by an acid-catalyzed reaction. The film loss in the non-irradiated portion becomes large, and the sensitivity tends to decrease in a system in which the irradiated portion has reduced solubility in an aqueous alkali solution due to an acid catalyzed reaction.

Examples of the solvent used in the present invention include glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol alkyl ether acetates such as methyl cellosolve acetate, diethylene glycols such as diethylene glycol monomethyl ether, and propylene glycol methyl ether acetate. Propylene glycol alkyl ether acetates, aromatic hydrocarbons such as toluene, ketones such as cyclohexanone, and esters such as 2-hydroxypropionic acid can be used. The amount of the solvent used is preferably 50 to 95% by weight, and more preferably 70 to 95% by weight, based on the photosensitive resin composition. If the amount of the solvent is too small, the solvent is not sufficiently soluble in the resist material. If the amount of the solvent is too large, a sufficient film thickness cannot be obtained when the resist film is used.

The photosensitive resin composition of the present invention has a coating property,
For example, in order to prevent striation (unevenness in film thickness) and improve developability, a surfactant can be added. As the surfactant, for example, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, and commercially available products are Megafax F171 and F173 (Dainippon Ink and Chemicals, Inc.). Product name), Florard FC430, FC43
1 (trade name of Sumitomo 3M Ltd.), organosiloxane polymer KP341 (trade name of Shin-Etsu Chemical Co., Ltd.) and the like. Further, the photosensitive resin composition of the present invention may optionally contain a storage stabilizer, a dissolution inhibitor, and the like.

With the photosensitive resin composition of the present invention, a resist image is produced by forming a resist film on a substrate such as a wafer or glass and irradiating with active actinic rays and developing. A conventionally well-known method can be adopted as the method. There are no particular restrictions on the conditions of irradiation with actinic radiation and development. For example, radiation such as far ultraviolet rays such as excimer lasers, X-rays such as synchrotron radiation, and charged particle beams such as electron beams are used.

Examples of the developer for the photosensitive resin composition of the present invention include inorganic alkalis such as sodium hydroxide, primary amines such as ethylamine, secondary amines such as diethylamine, and secondary amines such as triethylamine. Tertiary amines,
Alkaline aqueous solutions in which alcohol amines such as dimethylethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide and choline, or cyclic amines such as piperidine are used are used.

[0030]

In general, in a positive photosensitive resin composition, increasing the ratio of the dissolution rate of the irradiated part to the unirradiated part in the developer leads to higher resolution. The polyphenols added in the present invention have the effect of sufficiently slowing the dissolution rate of the unirradiated portion in the developing solution, whereby high resolution of the positive photosensitive resin composition could be achieved. In order to evaluate the dissolution inhibiting effect on an aqueous alkali solution produced by blending the above component (c) with the above component (a),
The ratio of the dissolution rate of the component (a) to the dissolution rate of a 2.38% by weight aqueous solution of tetramethylammonium hydroxide when 5 parts by weight of the component (c) is added to 100 parts by weight of the component (a). Was measured. The larger the numerical value of the parameter representing the dissolution inhibition effect, the greater the dissolution inhibition effect, and high resolution of the positive photosensitive resin composition is expected. In a normal alkali-soluble resin, this ratio is 4 to
Although it was 10, the ratio can be increased to 30 to 100 by adding a polyphenol having a specific molecular structure.

Further, the heat resistance of the resist material is greatly influenced by the molecular weight and the molecular weight distribution of the base resin. The higher the molecular weight or the lower the proportion of the low molecular weight component that lowers the heat resistance, the higher the heat resistance of the resist material. This time, since the sensitivity decreases when the molecular weight of the alkali-soluble resin that is the base resin is increased, 0 to 10% by weight of a low molecular weight component having a polystyrene reduced molecular weight of 2,000 or less
And Although the sensitivity and resolution are also reduced by reducing the low molecular weight component, the addition of the above-mentioned polyphenols does not lower the sensitivity and the resolution can be further improved.

[0032]

The present invention will be described below with reference to examples. Synthesis Example 1 m-cresol 328.1 g, p-cresol 40 in a separable flask equipped with a stirrer, a condenser and a thermometer.
0.9 g, 361.2 g of 37% by weight formalin and 2.2 g of oxalic acid were charged, and the separable flask was immersed in an oil bath.
The polycondensation was carried out for 3 hours while keeping the internal temperature at 97 ° C while stirring. Then, the internal temperature was raised to 180 ° C. and the pressure inside the reaction vessel was simultaneously reduced to 10 to 20 mmHg to recover unreacted cresol, formaldehyde, water and oxalic acid. Then, the melted resin was placed in a metal vat to collect the cresol novolac resin. This resin is referred to as a resin 1-1.

Synthesis Example 1-2 550 g of the resin obtained in Synthesis Example 1 was dissolved in 1100 g of ethyl cellosolve acetate to form a resin varnish, and 1000 g of toluene and 1000 g of hexane were mixed and stirred for 30 minutes and then left to stand. As a result, a dense phase having a high molecular weight component was obtained in the lower layer. By separating this concentrated phase and drying it under reduced pressure, an alkali aqueous solution-soluble resin with reduced low molecular weight components could be obtained (hereinafter, this resin is referred to as resin 1-2). Resin 1
-2 was analyzed by GPC, and the weight ratio of the low molecular weight component having a polystyrene reduced weight average molecular weight of 2,000 or less was 5% by weight.

Synthesis Example 2 Cresol novolac resin CN-19 (Meiwa Kasei Co., Ltd.)
200 g of methyl isobutyl ketone was dissolved into 800 g of a resin varnish, the resin varnish was gradually added dropwise to 1000 g of hexane, and the mixture was stirred for 30 minutes, and then the precipitate was recovered and dried under reduced pressure to remove low molecular weight components. It was possible to obtain a reduced alkali aqueous solution soluble resin (hereinafter, this resin is referred to as resin 2). Resin 2 to GPC
As a result, the weight ratio of the low molecular weight component having a polystyrene reduced weight average molecular weight of 2,000 or less was 7% by weight.

Synthesis Example 3 In a separable flask equipped with a stirrer, poly (p-vinylphenol) (trade name: Linker M, Maruzen Petrochemical Co., Ltd.)
20 ml) and 300 ml of ethyl acetate.
℃) to dissolve. Then, in the flask,
-Dihydro-2H-pyran 105 g, 12N hydrochloric acid 0.5
After adding ml, the mixture was stirred at room temperature for 1 hour, and then left at room temperature for 3 days. Next, 160 ml of a 2.38% by weight aqueous solution of tetramethylammonium hydroxide was added to the reaction solution, and the mixture was stirred well, and the organic layer was taken out. The obtained organic layer solution was washed three times with 300 ml of distilled water, and then the organic layer was dried and concentrated by an evaporator. Concentrated solution 50
Reprecipitation was carried out using 500 ml of petroleum ether per ml. After the reprecipitation operation was repeated twice, the product was dried in a vacuum dryer (3 mmHg, 40 ° C.) for 8 hours, and poly (95%) of the hydroxyl groups in the polymer were replaced with tetrahydropyranyl groups. 22 g of (p-vinylphenol) were obtained.

Synthesis Example 4 25 g of silver trifluoromethanesulfonate was dissolved in 200 ml of tetrahydrofuran, and 20 g of trimethylsulfonium iodide was added thereto and stirred. After reacting at room temperature for about 1 day, the precipitated silver iodide is removed by filtration. The filtrate was concentrated, and the obtained crude product was recrystallized using ethyl alcohol to obtain 17 g of trimethylsulfoniotrifluoromethanesulfonate.

Synthesis Example 5 In a separable flask equipped with a stirrer, a condenser, a water separator and a thermometer, 134.0 g of 2,5-xylenol, 33.7 g of salicylaldehyde, 0.83 g of p-toluenesulfonic acid and toluene. 268 g was charged, the separable flask was immersed in an oil bath, the internal temperature was kept at 115 ° C., and the reaction was carried out for 16 hours while removing condensed water. After that, 50 contents
The mixture is filtered at ℃, and the filtrate is dissolved in 580 g of methanol at 25 ℃. Dissolved methanol solution into ion-exchanged water 1
By putting in 450 g, filtering and drying the precipitate,
90 g of a triphenylmethane derivative represented by the formula (X) was obtained.

Embedded image Hereinafter, this triphenylmethane derivative is referred to as polyphenol 1.

Example 1 In a separable flask equipped with a stirrer, Synthesis Example 1-1
82.8 g of the resin 1-1 obtained in 1., 9.2 g of bisphenol A as a polyphenol compound, 8 g of poly (p-vinylphenol) in which the hydroxyl group obtained in Synthesis Example 3 is protected by a tetrahydropyranyl group, and active actinic radiation After charging 5 g of trimethylsulfoniotrifluoromethanesulfonate obtained in Synthesis Example 4 and 300 g of methyl cellosolve acetate as a compound which produces an acid upon irradiation, and visually confirming that they were dissolved and became a uniform solution, they were placed in a water bath at 40 ° C. Soak 3
Stirred for 0 hours. Then, the solution was filtered through a membrane filter having a pore size of 0.1 μm to prepare a resist solution (positive type chemically amplified photosensitive resin composition).

The obtained resist solution was applied onto a silicon wafer and heat-treated at 120 ° C. for 10 minutes to obtain a resist film having a thickness of 1.0 μm. An electron beam drawing apparatus with an accelerating voltage of 50 kV is used to draw a hole pattern on the resist at a dose of 3.5 μC / cm ² and then heat treated at 100 ° C. for 10 minutes to form an alkaline aqueous solution of the latent image portion of the resist. Promoted a reaction that increased the solubility of After this heat treatment, 2.38% by weight of tetramethylammonium hydroxide
The resist film on which a latent image was formed was developed using an aqueous solution for 120 seconds to obtain a positive resist pattern. As a result of observing the sectional shape of the 0.2 μm hole pattern with an electron microscope,
The resist pattern was rectangular and good. The amount of film reduction after development was 0.02 μm, which was good.

Example 2 Example 1 was repeated except that 9.2 g of tris (4-hydroxyphenyl) methane (manufactured by Honshu Kagaku Co.) was used instead of 9.2 g of bisphenol A as the polyphenol compound. Prepare a resist solution (positive type chemically amplified photosensitive resin composition) in the same manner as above, and add 5.0 μC / cm
^An electron beam writing experiment was performed with a dose of ² . As a result of observing the cross-sectional shape of the 0.2 μm hole pattern with an electron microscope, the resist pattern was rectangular and good. The amount of film reduction after development was 0.02 μm, which was good.

Example 3 In the same manner as in Example 1, except that 9.2 g of polyphenol 1 obtained in Synthesis Example 5 was used instead of 9.2 g of bisphenol A as the polyphenol compound, a resist solution ( A positive type chemically amplified photosensitive resin composition) was prepared, and an electron beam drawing experiment was conducted at an irradiation dose of 5.5 μC / cm ² . As a result of observing the cross-sectional shape of the 0.2 μm hole pattern with an electron microscope, the resist pattern was rectangular and good. The amount of film reduction after development is 0.02 μm
Was good.

Example 4 A resist was prepared in the same manner as in Example 1 except that 9.2 g of dimethylbiphenol (manufactured by Honshu Kagaku Co., Ltd.) was used instead of 9.2 g of bisphenol A as the polyphenol compound. Was prepared, and an electron beam drawing experiment was conducted at an irradiation dose of 3.8 μC / cm ² . As a result of observing the cross-sectional shape of the 0.2 μm hole pattern with an electron microscope, the resist pattern was rectangular and good. The amount of film reduction after development was 0.02 μm, which was good.

Example 5 A resist solution was prepared in the same manner as in Example 1 except that cresol novolak resin CN-19 (manufactured by Meiwa Kasei Co., Ltd.) was used in place of Resin 1. 8 μC /
An electron beam lithography experiment was performed with an irradiation dose of cm ² . As a result of observing the cross-sectional shape of the 0.2 μm hole pattern with an electron microscope, the resist pattern was rectangular and good. The amount of film reduction after development was 0.02 μm, which was good.

Example 6 In a separable flask equipped with a stirrer, Synthesis Example 1-2
78.2 g of the resin 1-2 obtained in 1), 13.8 g of bisphenol A as a polyphenol compound, and poly (p- with the hydroxyl group obtained in Synthesis Example 2 protected by a tetrahydropyranyl group.
Vinylphenol), 8 g, 5 g of trimethylsulfoniotrifluoromethanesulfonate obtained in Synthesis Example 3 as a compound which produces an acid by actinic radiation and 300 g of methyl cellosolve acetate were charged, and it was visually confirmed that a uniform solution was obtained. After confirming, it was immersed in a water bath at 40 ° C. and stirred for 30 hours. Then, the solution was filtered through a membrane filter having a pore size of 0.1 μm to prepare a resist solution (positive type chemically amplified photosensitive resin composition). The obtained resist solution was applied on a silicon wafer and heat-treated at 120 ° C. for 10 minutes to obtain a resist film having a film thickness of 1.0 μm.

A hole pattern was drawn on the resist at an irradiation amount of 3.5 μC / cm ² using an electron beam drawing device with an acceleration voltage of 50 kV on this substrate, and then heat treatment was performed at 100 ° C. for 10 minutes to form a latent image portion of the resist. Promoted the reaction of increasing the solubility of the above in an alkaline aqueous solution. After this heat treatment, the resist film on which the latent image was formed was developed for 120 seconds using a 2.38 wt% aqueous solution of tetramethylammonium hydroxide to obtain a positive resist pattern. As a result of observing the cross-sectional shape of the 0.2 μm hole pattern with an electron microscope, the resist pattern was rectangular and good. The amount of film reduction after development was 0.02 μm, which was good. Even if the formed resist pattern was left on a hot plate at 120 ° C. for 5 minutes, the resist pattern was not deformed and the heat resistance was good.

Example 7 In Example 6, resin 2 was used instead of resin 1-2, and bisphenol A was added as a polyphenol compound.
Dimethylbiphenol (Honshu Chemical Co., Ltd.) instead of 3.8 g
A resist solution (positive chemical amplification type photosensitive resin composition) was prepared in the same manner as in Example 6 except that 13.8 g of the product was used, and electrons were irradiated at an irradiation amount of 3.8 μC / cm ^2. A line drawing experiment was conducted. As a result of observing the sectional shape of the 0.2 μm hole pattern with an electron microscope, the resist pattern was rectangular and was good. The amount of film loss after development is 0.02μ.
m was good. Even if the formed resist pattern was left on a hot plate at 120 ° C. for 5 minutes, the resist pattern was not deformed and the heat resistance was good.

Example 8 In the same manner as in Example 6, except that 13.8 g of polyphenol 1 obtained in Synthesis Example 5 was used instead of 13.8 g of bisphenol A as the polyphenol compound, a resist solution ( A positive type chemically amplified photosensitive resin composition) was prepared, and an electron beam drawing experiment was conducted at an irradiation dose of 5.5 μC / cm ² . As a result of observing the sectional shape of the 0.2 μm hole pattern with an electron microscope, the resist pattern was rectangular and was good. The amount of film loss after development is 0.02.
μm, which was good. Even if the formed resist pattern was left on a hot plate at 120 ° C. for 5 minutes, the resist pattern was not deformed and the heat resistance was good.

Comparative Example 1 A resist solution was prepared in the same manner as in Example 1 except that polyphenols were not added.
An electron beam writing experiment was conducted at an irradiation dose of 5 μC / cm ² . 0.4
As a result of observing the sectional shape of the hole pattern of μm with an electron microscope, the resist pattern was rectangular and good.
However, the hole pattern smaller than that was not resolved and the resolution was inferior to that of the resist containing the polyphenol compound.

Comparative Example 2 A resist solution was prepared in the same manner as in Example 6 except that polyphenols were not added.
An electron beam writing experiment was conducted at an irradiation dose of 5 μC / cm ² . 0.4
As a result of observing the sectional shape of the hole pattern of μm with an electron microscope, the resist pattern was rectangular and good.
However, the hole pattern smaller than that was not resolved and the resolution was inferior to that of the resist containing the polyphenol compound.

[0050]

The positive type chemically amplified photosensitive resin composition according to claim 1 is excellent in sensitivity and resolution with respect to ultraviolet rays, deep ultraviolet rays, electron beams, X-rays and other active actinic rays. The positive type chemically amplified photosensitive resin composition according to claim 2 has excellent sensitivity, resolution and heat resistance to ultraviolet rays, deep ultraviolet rays, electron beams, X-rays and other active actinic rays. The method for producing a resist image according to claim 3 is excellent in resolution.
A resist pattern having excellent resolution and heat resistance can be manufactured.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location H01L 21/027 H01L 21/30 502R 569F (72) Inventor Mitsuaki Hashimoto 4 chome, Higashimachi, Hitachi City, Ibaraki Prefecture 13-1 Hitachi Chemical Co., Ltd. Yamazaki Plant (72) Inventor Toshio Sakamizu 1-chome, Higashi Koigakubo, Kokubunji City, Tokyo 280-Inside Central Research Laboratory, Hitachi, Ltd. (72) Inventor Hiroshi Shiraishi 1-chome, Higashi Koigakubo, Kokubunji City, Tokyo No. 280, Central Research Laboratory, Hitachi, Ltd.

Claims (3)

[Claims] (1) an aqueous alkali-soluble resin,
(B) General formula (I): (In the formula, R ¹ and R ² are each independently hydrogen and a carbon number of 1 to
4 represents an alkyl group, an aryl group or an aryl group having a phenolic hydroxyl group, R ³ and R ⁴ each independently represent an alkyl group having 1 to 3 carbon atoms, and f and g each independently represent 0, 1 or 2 And h and i are each independently 1, 2 or 3) or a polyphenol compound represented by the general formula (II) (In the formula, R ⁵ and R ⁶ each independently represent an alkyl group having 1 to 3 carbon atoms, j and k are each independently 0, 1 or 2, and 1 and m are each independently 1, 2 or Three
A polyphenol compound represented by the formula (1), (c) a compound which produces an acid upon irradiation with active actinic radiation, and (d) a vinyl polymer having a side chain with an acid-decomposable group whose solubility in an alkaline aqueous solution is increased by an acid-catalyzed reaction. A positive type chemically amplified photosensitive resin composition containing a combination. 2. The positive type chemically amplified photosensitive resin composition according to claim 1, wherein the content of the low molecular weight component having a polystyrene reduced molecular weight of 2,000 or less in the alkali aqueous solution soluble resin is 10% by weight or less. 3. A method for producing a resist image, which comprises irradiating a coating film of the positive type chemically amplified photosensitive resin composition according to claim 1 or 2 with active actinic radiation and then developing the resist image. .