JPH1010731A - Negative photosensitive resin composition and production of resist image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a negative photosensitive resin compsn. having high sensitivity and high resolution and to provide a production method of a resist image with which highly integrated circuits can be easily produced. SOLUTION: This negative photosensitive resin compsn. contains a resin soluble with an alkali soln., bromomethyl arylketone or dibromomethyl arylketone, an amino resin and a phenol compd. expressed by formula. In formula, a and b are integers 1 to 3, x and y are integers 0 to 3 satisfying (a+x)<=4 and (b+y)<=4. This negative photosensitive resin compsn. is applied on a substrate, and then dried, exposed to light or irradiated with active radiation, heated and developed with an alkali soln.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative photosensitive resin composition and a method for producing a resist image, and more particularly to a negative photosensitive resin composition having excellent ability to form a fine pattern for producing a highly integrated circuit. And a method for producing a resist image using the same.

[0002]

2. Description of the Related Art Conventionally, as a conventional negative type resist, a resist based on a cyclized rubber and using an azide compound as a photosensitive agent has been known. This resist forms a negative pattern by causing a cross-linking reaction between the cyclized rubber and the azide compound by the irradiation of ultraviolet light, and insolubilizing the ultraviolet irradiation part. However, since the pattern swells during development, the resolution is inferior, and it has been difficult to form a fine pattern for a highly integrated circuit. In addition, it is necessary to use an organic solvent as a developer, which causes environmental and health problems.

Further, a negative resist based on an aqueous alkaline solution-soluble phenol resin and using azide compound as a photosensitive agent is described in JP-A-59-22833. In the case of this resist, a cross-linking reaction occurs between the phenol resin and the azide compound due to ultraviolet irradiation, and the ultraviolet-irradiated portion is insolubilized to form a negative pattern. In this case, an alkaline aqueous solution can be used as a developer because the aqueous solution is based on a phenol resin soluble in an alkaline aqueous solution.

However, in any of the above resists, the quantum yield of the cross-linking reaction is 1 or less in a process in which the azide compound is changed to an active molecular species by ultraviolet irradiation and a cross-linking reaction with the base resin occurs. There was a problem of low sensitivity. Therefore, Japanese Patent Application Laid-Open No.
In Japanese Patent Application Laid-Open Publication No. H11-176, a chemically amplified negative resist has been proposed in which the sensitivity is increased by causing a crosslinking reaction using an acid generated by ultraviolet irradiation as a catalyst. This chemically amplified resist can achieve high sensitivity because the acid generated by ultraviolet irradiation acts as a catalyst, but has a problem in that the generated acid diffuses to lower the resolution. Further, there is a problem that a slight acid generated by a dark reaction of the acid generator during storage of the negative resist composition acts as a catalyst to cause a cross-linking reaction, thereby changing the properties of the resist.

JP-A-6-59444 discloses a chemically amplified negative resist in which a non-irradiated portion of active radiation is highly dissolved by adding a phenol compound to the chemically amplified negative resist composition. Have been. However, although the phenol compounds described therein can improve the solubility of the non-irradiated portion of the active radiation kneading in the developer, the resolution for producing a highly integrated circuit has not been obtained, and However, depending on the type of the phenol compound, there is a problem that the sensitivity is lowered.

[0006]

The invention described in claim 1 provides a negative photosensitive resin composition having high sensitivity and high resolution. The invention described in claim 2 provides a negative photosensitive resin composition having further excellent developability. The third aspect of the present invention is to provide a method for producing a resist image which is easy to produce a highly integrated circuit by using these negative photosensitive resin compositions.

[0007]

SUMMARY OF THE INVENTION The present invention relates to an aqueous alkali-soluble resin, a bromomethylarylketone or dibromomethylarylketone, an amino resin, and a compound represented by the general formula (I):

Embedded image [Wherein, a and b are each an integer of 1 to 3, x and y are each an integer of 0 to 3, and (a +
x) is 4 or less, and (b + y) is 4 or less].

Further, the present invention relates to such a negative photosensitive resin composition, wherein the phenolic compound represented by the general formula (I) has a and b in the general formula (I) each being 1; The present invention relates to a negative photosensitive resin composition wherein x and y are each an integer of 0 to 2. Further, the present invention provides a method for producing a resist image, which comprises applying these negative photosensitive resin compositions onto a substrate, drying, exposing or irradiating with active radiation, heating, and then developing with an aqueous alkaline solution. About the law.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The alkaline aqueous solution-soluble resin used in the present invention is not particularly limited as long as it is a resin soluble in an alkaline aqueous solution, but is obtained by condensing phenols and aldehydes with an acid catalyst. Novolak resins are preferred. As phenols, phenol, cresol, xylenol, trimethylphenol, butylphenol, naphthol, catechol, pyrogallol, etc. can be used alone or in combination of two or more.
As the aldehydes, formaldehyde and paraformaldehyde are used.

The acid catalyst used for the condensation of phenols and aldehydes includes, for example, inorganic acids such as hydrochloric acid, nitric acid and sulfuric acid, and organic acids such as formic acid, oxalic acid and p-toluenesulfonic acid. . The amount of acid catalyst used is
1 × 10 ⁻⁵ to 1 × per 1 mol of the above phenols
It is preferably 10 ^-1 mol. The reaction temperature of the condensation is
It can be appropriately changed according to the reactivity of the reaction raw materials,
It is usually 70 to 130 ° C. Examples of the condensation method include a method in which the above-mentioned phenols, aldehydes and acid catalyst are charged at once, a method in which the above-mentioned phenols and aldehydes are added in the presence of the acid catalyst as the reaction proceeds. After the completion of the condensation, under reduced pressure, for example, 10 to 50 mm
The temperature in the reaction system is raised to 150 to 200 ° C. with Hg to remove unreacted raw materials, condensed water, acid catalyst and the like present in the reaction system, and after cooling, recover the resin.

The acid generator used in the present invention contains bromomethyl aryl ketone or dibromomethyl aryl ketone. Specific examples of bromomethylarylketone or dibromomethylarylketone include 2-bromoacetylnaphthalene, 2-bromoacetyl-6,7-
Dimethoxynaphthalene, 2-dibromoacetylnaphthalene, 2-dibromoacetyl-6,7-dimethoxyquinaphthalene, 1-hydroxy-4-bromo-2-bromoacetylnaphthalene, 1-hydroxy-4-bromo-2-dibromoacetylnaphthalene, 2-hydroxy-1-bromoacetylnaphthalene, 1,4-bis (bromoacetyl) benzene, 4,4′-bis (bromoacetyl) biphenyl, 1,3,5-tris (bromoacetyl) benzene,
Examples thereof include 1,3,5-tris (dibromoacetyl) benzene and the like, and these may be used alone or in combination of two or more.

The amino resin used in the present invention includes:
There is no particular limitation, and for example, melamine-formaldehyde resin, benzoguanamine-formaldehyde resin, glycoluril-formaldehyde resin, urea-formaldehyde resin and the like can be used alone or in combination of two or more.

The compounds represented by the general formula (I) include:
There are compounds represented by the following formulas 3 [Structural formulas (A) to (G)].

[0014]

Embedded image

From the viewpoint of enhancing the developability of the photosensitive resin composition of the present invention, as the phenol compound represented by the general formula (I), a and b are each 1 in the general formula (I), and x and Compounds in which y is an integer of 0 to 2 are preferred, and a and b are each 1;
Compounds in which x and y are each 0 or 1 are preferred.

The photosensitive resin composition of the present invention is preferably used in the state of being dissolved in a solvent.
It is applied to the surface of silicon, aluminum, quartz, glass substrates, etc. At this time, a solvent to be used is appropriately selected and used. Examples thereof include ketone solvents such as acetone, ethyl ketone and cyclohexanone, aromatic solvents such as toluene and xylene, methyl cellosolve, methyl cellosolve acetate, and ethyl cellosolve acetate. Cellosolve solvents such as tart, ethyl lactate, butyl acetate, isoamyl acetate, propylene glycol methyl ether acetate,
Ester solvents such as propylene glycol ethyl ether acetate, methyl pyruvate, ethyl pyruvate and propyl pyruvate, and alcohol solvents such as methanol, ethanol, propanol, propylene glycol methyl ether, propylene glycol ethyl ether and propylene glycol propyl ether Are preferably used alone or in combination of two or more.

The negative-type photosensitive resin composition of the present invention contains an aqueous alkali-soluble resin 100 in view of resolution and sensitivity.
The acid generator is preferably used in an amount of 5 to 40 parts by weight, more preferably 10 to 30 parts by weight, based on the weight of the acid generator. From the same viewpoint, the amino resin is preferably used in an amount of 3 to 50 parts by weight, more preferably 5 to 20 parts by weight, based on 100 parts by weight of the aqueous alkali-soluble resin. From the same viewpoint, the phenol compound represented by the general formula (I) is preferably used in an amount of 0.5 to 30 parts by weight, more preferably 1 to 20 parts by weight. The solvent is usually an aqueous alkali solution soluble resin 1
It is preferably used in the range of 200 to 2000 parts by weight with respect to 00 parts by weight.

The negative photosensitive resin composition of the present invention may contain, as the purpose requires, a secondary component, for example, a surfactant such as perfluoroalkyl ether or perfluoroalkyl ester in order to make the coating film thickness uniform. And an adhesiveness improver such as 1,1,1,3,3,3-hexamethyldisilazane for improving the adhesion to the substrate.

The negative resist composition of the present invention is applied onto a substrate and dried to form a photosensitive or radiation-sensitive film (hereinafter, photosensitive) having high sensitivity to ultraviolet rays, far ultraviolet rays, or radiation such as X-rays and electron beams. The film is simply referred to as a radiation-sensitive film). Thereafter, exposure or irradiation with actinic radiation is performed, heated, and then developed to form a resist image. When the above radiation-sensitive film is exposed to light or irradiated with radiation, the acid generator in the film at that portion is decomposed to generate an acid. Thereafter, when heated, the generated acid acts as a catalyst to cause a cross-linking reaction between the amino resins and between the amino resin and the aqueous alkali-soluble resin. Then, by developing with an aqueous alkali solution, the radiation-sensitive film in the unirradiated portion is dissolved, and a negative resist image is formed.

For the exposure or radiation irradiation, ultraviolet rays, far ultraviolet rays, or radiations such as X-rays and electron beams are used, and are performed by known means. The heating conditions after exposure or radiation irradiation are appropriately determined depending on the components of the radiation-sensitive film, and are, for example, performed on a hot plate at 60 to 130 ° C. for 30 seconds to 10 minutes. Examples of the developing solution of the alkaline aqueous solution include an aqueous solution of 5% by weight or less, preferably 1.5 to 3.0% by weight of an alkaline substance such as sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, and choline. Used.

[0021]

Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.
The m- / p-cresol novolak resin used in the following Examples and Comparative Examples was prepared by charging cresol and formaldehyde at the ratios described in each Example and Comparative Example, and condensing at 97 ° C. for 3 hours using oxalic acid as a catalyst. After one
It was synthesized by raising the temperature to 80 ° C. and removing unreacted cresol, formaldehyde, water and acid under reduced pressure (10 mmHg).

Example 1 m-cresol and p-cresol (prepared amounts by weight: m-cresol / p-cresol = 50/50) 1.0
0 mol and 0.71 mol of formaldehyde are condensed and 100 parts by weight of m- / p-cresol novolak resin (weight average molecular weight in terms of polystyrene of 15,000), 1-hydroxy-4-bromo-2-bromoacetylnaphthalene 20 10 parts by weight of a melamine-formaldehyde resin (Cymel 303, manufactured by Mitsui Cyanamid Co., Ltd.) and 10 parts by weight of a compound having the structural formula (F) (hereinafter referred to as phenol compound (F)) in propylene glycol monomethyl Ether acetate 400
After being dissolved in parts by weight, the solution was filtered through a membrane filter having a pore size of 0.2 μm to obtain a negative photosensitive resin composition.

The obtained composition was applied on a hexamethyldisilazane-treated silicon substrate and dried on a hot plate at 100 ° C. for 120 seconds to form a radiation-sensitive film having a thickness of 1.0 μm. Thereafter, an electron beam lithography system (HL-600, manufactured by Hitachi, Ltd.) with an acceleration voltage of 50 kV was used to obtain 7 μC / cm ^2.
Was irradiated with an electron beam at 90 ° C. for 90 seconds on a hot plate, and then developed with a 2.38 wt% aqueous solution of tetramethylammonium hydroxide for 200 seconds to obtain a minimum line width of 0.20 μm. A fine line / spacing pattern was formed.

Example 2 m-cresol and p-cresol (prepared amounts by weight: m-cresol / p-cresol = 60/40) 1.0
0 mol and 0.72 mol of formaldehyde are condensed, and 100 parts by weight of m- / p-cresol novolak resin (weight average molecular weight in terms of polystyrene of 15,000), 1,3,5-tris (bromoacetyl) benzene 2
0 parts by weight, 10 parts by weight of a melamine-formaldehyde resin (Cymel 300, manufactured by Mitsui Cyanamid Co., Ltd.) and 20 parts by weight of a phenol compound (F) are dissolved in 400 parts by weight of propylene glycol monomethyl ether acetate, and then a membrane having a pore size of 0.2 μm. The mixture was filtered with a filter to obtain a negative photosensitive resin composition.

The obtained composition was applied on a hexamethyldisilazane-treated silicon substrate and dried on a hot plate at 100 ° C. for 120 seconds to form a radiation-sensitive film having a thickness of 1.0 μm. After that, an electron beam was irradiated at a dose of 8 μC / cm ² by the electron beam lithography apparatus used in Example 1,
Heat treatment was performed on a hot plate at 0 ° C. for 120 seconds, followed by development with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide for 60 seconds. As a result, a fine pattern having a minimum line width of 0.20 μm and a line / interval was formed.

Example 3 m-cresol and p-cresol (prepared amounts by weight: m-cresol / p-cresol = 50/50) 1.0
100 parts by weight of m- / p-cresol novolak resin (weight average molecular weight of 15,000 in terms of polystyrene) synthesized by condensing 0 mol and 0.71 mol of formaldehyde, 15 parts by weight of 1,4-bis (bromoacetyl) benzene , Melamine-formaldehyde resin (Cymel 30)
0, 10 parts by weight of Mitsui Cyanamid Co., Ltd.) and 10 parts by weight of phenol compound (F) were dissolved in 400 parts by weight of cyclohexanone, and then filtered through a membrane filter having a pore size of 0.2 μm to obtain a negative photosensitive resin composition. Was.

The obtained composition was applied onto a hexamethyldisilazane-treated silicon substrate and dried on a hot plate at 100 ° C. for 120 seconds to form a radiation-sensitive film having a thickness of 1.0 μm. Then, after irradiating an electron beam with an irradiation amount of 7 μC / cm ² by the electron beam lithography apparatus used in Example 1,
Heat treatment was performed on a hot plate at 0 ° C. for 120 seconds, followed by development with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide for 60 seconds. As a result, a fine pattern having a minimum line width of 0.20 μm and a line / interval was formed.

Example 4 m-cresol and p-cresol (prepared amounts by weight: m-cresol / p-cresol = 50/50) 1.0
M- / p-cresol novolak resin (weight average molecular weight in terms of polystyrene: 14,000) 100 parts by weight synthesized by condensing 0 mol and 0.70 mol of formaldehyde, 1,3,5-tris (bromoacetyl) benzene 1
5 parts by weight, 15 parts by weight of a melamine-formaldehyde resin (Cymer 303, manufactured by Mitsui Cyanamid Co., Ltd.) and 5 parts by weight of a phenol compound (F) were dissolved in 400 parts by weight of cyclohexanone, followed by filtration through a membrane filter having a pore size of 0.2 μm. Thus, a negative photosensitive resin composition was obtained.

The obtained composition was applied on a hexamethyldisilazane-treated silicon substrate and dried on a hot plate at 100 ° C. for 120 seconds to form a radiation-sensitive film having a thickness of 1.0 μm. Then, after irradiating with an electron beam at an irradiation dose of 5 μC / cm ² by the electron beam lithography system used in Example 1,
When heat-treated on a hot plate at 0 ° C. for 120 seconds and then developed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide for 100 seconds, the minimum line width was 0.20 μm.
The fine pattern of the line / spacing was formed.

Comparative Example 1 A negative photosensitive resin composition was obtained in the same manner as in Example 1 except that the phenol compound (F) was not used, and a radiation-sensitive film was formed. Then, after irradiating an electron beam with an irradiation amount of 5 μC / cm ² by the electron beam lithography apparatus used in Example 1, 100
Heat treatment on a hot plate at 120 ° C. for 120 seconds, and then with a 3.38% by weight aqueous solution of tetramethylammonium hydroxide.
When development was performed for 00 seconds, a fine pattern having a minimum line width of 0.30 μm and a line / interval was formed.

Comparative Example 2 A negative photosensitive resin composition was obtained in the same manner as in Example 1 except that a compound having the structural formula shown below was used instead of the phenol compound (F), and a radiation-sensitive film was formed. . After that, the electron beam lithography apparatus used in Example 1
After irradiating with an electron beam at an irradiation amount of ² , a heat treatment was performed on a hot plate at 100 ° C. for 120 seconds, and then development was performed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide for 200 seconds. The fine pattern of the line / spacing was formed.

Embedded image

Comparative Example 3 A negative photosensitive resin composition was prepared in the same manner as in Example 1 except that 2,4,6-tribromophenol was used instead of 1-hydroxy-4-bromo-2-bromoacetylnaphthalene. Thus, a radiation-sensitive film was formed. Then, after irradiating with an electron beam at a dose of 8 μC / cm ² by the electron beam lithography apparatus used in Example 1, heat treatment was performed on a hot plate at 100 ° C. for 120 seconds, and then 2.38% by weight of tetramethylammonium hydroxide When development was performed with the aqueous solution for 300 seconds, a fine pattern having a minimum line width of 0.8 μm and a line / interval was formed.

As can be seen from the above examples and comparative examples, the examples of the present invention have excellent sensitivity and resolution,
Comparative Example 1 in which a fine pattern could be produced by a short time development, but no phenol compound (F) was added,
In Comparative Example 3 using 2,4,6-tribromophenol as the acid generator, the resolution was inferior, and the minimum line width was inferior to that of the example even after long-term development. Also,
In Comparative Example 2 in which the phenol compound of Chemical formula 4 was used in place of the phenol compound (F), the sensitivity was lowered and the resolution was inferior to that of the example.

[0034]

According to the present invention, the negative photosensitive resin composition has excellent sensitivity and resolution to ultraviolet rays, far ultraviolet rays, electron beams, X-rays and other active actinic rays, and can form a highly integrated circuit. As a negative-type photosensitive resin composition. The negative photosensitive resin composition according to claim 2 has further excellent sensitivity and resolution, and is most suitable for a negative photosensitive resin composition for producing a highly integrated circuit. According to the method for manufacturing a resist image according to claim 3, a highly integrated circuit or the like can be easily formed.
A fine pattern can be created.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shigeru Koibuchi 4-3-1-1, Higashicho, Hitachi City, Ibaraki Pref. Hitachi Chemical Co., Ltd. Yamazaki Factory

Claims (3)

[Claims] An aqueous alkaline solution-soluble resin, bromomethyl aryl ketone or dibromomethyl aryl ketone,
Amino resin and Chemical formula 1 [General formula (I)] [Wherein, a and b are each an integer of 1 to 3, x and y are each an integer of 0 to 3, and (a +
x) is 4 or less, and (b + y) is 4 or less]. 2. The phenol compound represented by the general formula (I) is a compound in which a and ぴ b are each 1 and x and ぴ y are each an integer of 0 to 2 in the general formula (I). The negative photosensitive resin composition according to claim 1. 3. A method comprising applying the negative photosensitive resin composition according to claim 1 on a substrate, drying, exposing or irradiating with actinic radiation, heating, and then developing with an aqueous alkali solution. Characteristic method of manufacturing resist image.