JP6852234B2 - Photoresist composition and its cured product - Google Patents

Description

The present invention relates to a photoresist composition and a cured product thereof.

Microfabrication in the manufacturing process of semiconductor devices such as ICs (integrated circuits) and LSIs (large-scale integrated circuits) involves an underlying insulating film, semiconductor film, and metal film via a resist film in which a pattern is formed by exposure and development. It is done by etching. After the microfabrication, that is, the etching is completed, the resist film used for the mask is usually subjected to a resist stripping step of removing it from the substrate surface using a stripping solution such as N-methylpyrrolidone (NMP).

As for the patterning of the resist film as described above, a method of forming a resist pattern by photolithography and forming a pattern by etching with a chemical solution or dry etching using plasma is widely applied as a method for manufacturing many electronic devices such as semiconductors. ing. Further, as a patterning method for a material that is difficult to etch, after forming a resist pattern by photolithography, a thin film such as a metal or an insulator is formed by means such as thin film deposition, which is unnecessary in the resist peeling step. There is a so-called lift-off method in which the portions are also peeled off at the same time to form a thin film pattern.

In recent years, with the miniaturization and high density of electronic devices such as semiconductor integrated circuits, fine patterning is required for resist films, and high resolution is required for resist materials. Further, in the conventional development process, a strong alkaline developer such as tetramethylammonium hydroxide (TMAH) has been used, but since electronic devices using oxide semiconductors and the like cause problems such as corrosion, sodium carbonate It is necessary to use a weak alkaline developer such as an aqueous solution (Patent Document 1 etc.). For this reason, resist materials are required to be capable of high-resolution fine patterning even with a weak alkaline developer.

Further, in order to improve the etching durability of the resist film, a semi-permanent resist film to be exposed using a short wavelength exposure apparatus after development may be cured (Patent Document 2 and the like).

Japanese Unexamined Patent Publication No. 10-07923 Japanese Unexamined Patent Publication No. 11-202501

When exposure is performed using a short wavelength exposure apparatus as described above after developing the resist pattern, a resist film having excellent etching resistance and dimensional stability can be formed, but the resist film is less likely to be peeled off in the subsequent resist peeling step. There is a problem such as. Further, as described above, the resist material is required to have a performance capable of fine patterning with high resolution even with a weak alkaline developer. A resist material that can simultaneously satisfy such a plurality of conflicting requirements has not yet been developed.

Therefore, an object of the present invention is to provide a photoresist composition which can be developed even with a weak alkaline developer, can obtain fine patterning with high resolution, and has excellent peelability.

Another object of the present invention is to provide a cured product obtained by curing a photoresist composition.

The present inventors focused on the surface state of the resist film obtained through each of the prebaking, exposure, and developing steps and the surface state of the resist film further irradiated with ultraviolet rays after the prebaking, exposure, and developing steps, and made a photoresist. I noticed that the relationship between the two differs greatly depending on the composition. Specifically, the surface roughness of the resist film that has been further irradiated with ultraviolet rays may be lower than that of the resist film that has undergone the prebaking, exposure, and developing steps. Further examination of this phenomenon revealed that the smoother the surface condition of the resist film subjected to ultraviolet irradiation with respect to the surface condition of the resist film that had undergone prebaking, exposure, and development steps, the more it was developed with a weak alkaline developer. Even in this case, it was found that the resist film obtained through prebaking, exposure and development had excellent resolvability, and the resist film further irradiated with ultraviolet rays had excellent peelability. The present invention is based on such findings.

That is, the photoresist composition according to the present invention is
(A) Carboxyl group-containing resin,
(B) photopolymerizable monomer and (C) thermosetting component,
A photoresist composition comprising
The photoresist composition is applied onto a flat substrate so that the cured film thickness is 2 μm ± 0.5 μm, and after prebaking at 75 ° C. for 30 minutes, ultraviolet rays 1 having a wavelength of 375 nm are applied to 1 in an air atmosphere. The surface of the cured film 1 formed by exposing to an exposure amount of 000 mJ / cm ² to cure the photoresist composition and then developing at 30 ° C. with a 1 wt% Na ₂ CO _{3 aqueous solution for 180 seconds.} Arithmetic mean roughness Ra is Ra1
The arithmetic average roughness Ra of the surface of the cured film 2 formed by further exposing the cured film 1 to ultraviolet rays 2 having wavelengths of 185 nm and 254 nm under an oxygen atmosphere at ^{an exposure amount of 25.2 J / cm 2 is Ra2.} When, the following formula:
Ra2 / Ra1 ≤ 4.5 × 10 ^-1
It is characterized by satisfying.

In the embodiment of the present invention, it is preferable that the (B) photopolymerizable monomer is at least one selected from (meth) acrylates.

In the embodiment of the present invention, the carboxyl group-containing resin (A) preferably has an acid value of 50 to 200 mgKOH / g.

In the embodiment of the present invention, the carboxyl group-containing resin (A) preferably has a weight average molecular weight of 5,000 to 100,000.

Further, the cured product according to another embodiment of the present invention is characterized in that it is obtained by curing a photoresist composition.

According to the present invention, in a photoresist composition containing a carboxyl group-containing resin, a photopolymerizable monomer, and a thermocurable component, the surface state (Ra1) of the cured film obtained by prebaking, exposing, and developing is applied. A photoresist composition such that the surface state (Ra2) of the cured film obtained by irradiating the cured film with ultraviolet rays having a wavelength shorter than that at the time of exposure ^{satisfies the relationship of Ra2 / Ra1 ≦ 4.5 × 10 -1.} Therefore, even when developed with a weak alkaline developing solution, the resist film obtained through prebaking, exposure and development has excellent resolvability, and the resist film further irradiated with ultraviolet rays thereafter has excellent peeling. Has sex.
Further, in another aspect of the present invention, it is possible to provide a cured product obtained by curing the photoresist composition.

[Photoresist composition]
The photoresist composition in the present invention contains (A) a carboxyl group-containing resin, (B) a photopolymerizable monomer, and (C) a thermosetting component as essential components, and Ra2 / Ra1 ≦ 4 It is characterized by satisfying the relationship of .5 × 10 ^-1. That is, the photoresist composition is applied onto a flat substrate so that the cured film thickness is 2 μm ± 0.5 μm, and after prebaking at 75 ° C. for 30 minutes, ultraviolet rays 1 having a wavelength of 375 nm are applied under an atmospheric atmosphere. The photoresist composition was cured by exposing it to an exposure amount of 1,000 mJ / cm ² , followed by a 180-second development treatment using a _{1 wt% Na 2} CO _{3 aqueous solution at 30 ° C.} Let Ra1 be the arithmetic mean roughness Ra of the surface.
The arithmetic average roughness Ra of the surface of the cured film 2 formed by further exposing the cured film 1 to ultraviolet rays 2 having wavelengths of 185 nm and 254 nm under an oxygen atmosphere at ^{an exposure amount of 25.2 J / cm 2 is Ra2.} When, the following formula:
Ra2 / Ra1 ≤ 4.5 × 10 ^-1
Is satisfied. Here, the arithmetic mean roughness Ra in the present invention means the surface roughness measured in accordance with JIS B0601: 2001 (ISO4287: 1997), and can be measured by a three-dimensional surface texture measuring machine or the like. .. Further, the values of Ra1 and Ra2 in the present invention shall mean the average value obtained by randomly measuring the surface of the cured film at 10 points. Specifically, using a laser microscope VK-X series (manufactured by KEYENCE CORPORATION) compatible with the non-contact measurement method, a cured coating in the range of 200 μm × 200 μm is used in accordance with JIS B0601: 2001 (ISO4287: 1997). The surface is randomly measured at 10 points with a microscope magnification of 100, and the average value is calculated. Further, as a condition for measuring Ra1 and Ra2, a glass substrate (for example, non-alkali glass such as Corning (registered trademark) EAGLE XG (registered trademark) Slim) is used as the flat substrate on which the cured film is formed. The surface roughness of the cured film is generally affected by the surface condition of the substrate when the cured film is formed, but the surface of the glass substrate is sufficiently smoother than the surface of the cured film, so that the glass substrate is sufficiently smooth. The values of Ra1 and Ra2 are not affected by the type of. Further, a metal halide lamp is used for irradiating ultraviolet rays 1, and a UV ozone cleaner (distance from the UV lamp light source to the irradiation surface is 1 cm, type: low-pressure mercury lamp (fused quartz), shape: A high-density, high-power grid lamp, ultraviolet intensity: 28 mW / cm ² ) is used.

If the photoresist composition such that Ra1 and Ra2 measured as described above ^{satisfy the relationship of Ra2 / Ra1 ≤ 4.5 × 10 -1} , prebake even when developed with a weak alkaline developer. The reason why the resist film obtained through exposure and development with ultraviolet rays 1 has excellent resolution and the resist film further exposed to ultraviolet rays 2 has excellent peelability is not clear, but the following Can be guessed. That is, in order to obtain a cured film having good resolution, the photoresist composition needs to contain a photoreactive component. However, if only the photoreactive component is used, the curing proceeds too much and the peelability of the cured film deteriorates. On the other hand, by blending a component that does not react with light into the photoresist composition, the peelability is improved, but the resolution tends to be insufficient. In addition, fillers and the like may be blended in the photoresist composition, and it is considered that these components also affect the resolution and peelability. It is considered that the characteristics of resolution and peelability are determined by the balance of various components contained in these photoresist compositions, but at the same time, these compounding components also affect the surface state of the cured film, and are described above. It can be inferred that if the component balance is such that a surface state that satisfies the specific conditions as described above is achieved, both resolution and peelability, which are contradictory issues, can be realized. However, this is just a guess, and the present invention is not bound by such a theory.

In the present invention, Ra1 is preferably 10 to 200 nm, more preferably 30 to 150 nm from the viewpoint of resolvability. From the viewpoint of peelability, Ra2 is preferably 4 to 60 nm, more preferably 10 to 50 nm.

Further, Ra1 and Ra2, it is necessary to satisfy the ^{Ra2 / Ra1 ≦ 4.5 × 10 -1} , preferably satisfies the ^{Ra2 / Ra1 ≦ 4.0 × 10 -1} .

As described above, the relationship between Ra1 and Ra2 and the preferable range of Ra1 and Ra2 are adjusted by the balance between the exposure-reacting component (that is, the curable component) contained in the photoresist composition and the other components. can do. For example, it can be adjusted according to the type and blending amount of (A) carboxyl group-containing resin, (B) photopolymerizable monomer, and (C) thermosetting component which are components constituting the photoresist composition of the present invention. Further, it can be appropriately adjusted depending on the type and blending amount of the filler and the like which are optional components. Hereinafter, each component constituting the photoresist composition of the present invention will be described.

<(A) Carboxyl group-containing resin>
As the carboxyl group-containing resin (A), various conventionally known resins having a carboxyl group in the molecule can be used. Since the photosensitive resin composition contains a carboxyl group-containing resin, it is possible to impart developability to the photoresist composition even if it is a weakly alkaline developer. In particular, a carboxyl group-containing photosensitive resin having an ethylenically unsaturated double bond in the molecule is preferable from the viewpoint of photocurability and development resistance. The ethylenically unsaturated double bond is preferably derived from acrylic acid or methacrylic acid or a derivative thereof. When only a carboxyl group-containing resin having no ethylenically unsaturated double bond is used, in order to make the composition photocurable, a compound having a plurality of ethylenically unsaturated groups in the molecule described later, that is, light It is necessary to use a polymerizable monomer together. Specific examples of the carboxyl group-containing resin include the following compounds (either oligomer or polymer).

(1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth) acrylic acid with an unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, or isobutylene.
(2) Diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates and aromatic diisocyanates, carboxyl group-containing dialcoic compounds such as dimethylolpropionic acid and dimethylolbutanoic acid, polycarbonate-based polyols and polyether-based compounds. Carboxyl group-containing urethane resin by double addition reaction of diol compounds such as polyols, polyester-based polyols, polyolefin-based polyols, acrylic-based polyols, bisphenol A-based alkylene oxide adduct diols, compounds having phenolic hydroxyl groups and alcoholic hydroxyl groups,
(3) Diisocyanate and bifunctional epoxy resin such as bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bixylenol type epoxy resin, biphenol type epoxy resin ( Meta) acrylate or its partial acid anhydride modified product, carboxyl group-containing photosensitive urethane resin by double addition reaction of carboxyl group-containing dialcohol compound and diol compound,
(4) During the synthesis of the resin according to (2) or (3), a compound having one hydroxyl group and one or more (meth) acryloyl groups in a molecule such as hydroxyalkyl (meth) acrylate is added to the terminal (4). Meta) Acryloylated carboxyl group-containing photosensitive urethane resin,
(5) During the synthesis of the resin according to (2) or (3), one isocyanate group and one or more (meth) acryloyl groups are formed in the molecule, such as an isophorone diisocyanate and pentaerythritol triacrylate isomorphic reaction product. Carboxyl group-containing photosensitive urethane resin, terminal (meth) acrylicized by adding the compound
(6) A carboxyl group-containing photosensitive resin obtained by reacting a bifunctional or higher polyfunctional (solid) epoxy resin with (meth) acrylic acid and adding a dibasic acid anhydride to a hydroxyl group existing in a side chain.
(7) Carboxyl in which (meth) acrylic acid is reacted with a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl group of a bifunctional (solid) epoxy resin with epichlorohydrin, and a dibasic acid anhydride is added to the generated hydroxyl group. Group-containing epoxy resin,
(8) A dicarboxylic acid such as adipic acid, phthalic acid, or hexahydrophthalic acid is reacted with a bifunctional oxetane resin, and the generated primary hydroxyl group is subjected to two bases such as phthalic anhydride, tetrahydrophthalic anhydride, and hexahydrophthalic anhydride. Carboxyl group-containing polyester resin with acid anhydride added,
(9) An epoxy compound having a plurality of epoxy groups in one molecule, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol, and (meth). Reacting with an unsaturated group-containing monocarboxylic acid such as acrylic acid, maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipine with respect to the alcoholic hydroxyl group of the obtained reaction product. A carboxyl group-containing photosensitive resin obtained by reacting a polybasic anhydride such as an acid,
(10) Reaction obtained by reacting an unsaturated group-containing monocarboxylic acid with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide. A carboxyl group-containing photosensitive resin obtained by reacting a product with a polybasic acid anhydride,
(11) Reaction obtained by reacting a reactive organism obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate by reacting an unsaturated group-containing monocarboxylic acid. Carboxyl group-containing photosensitive resin obtained by reacting a product with a polybasic acid anhydride,
(12) A carboxyl group-containing photosensitive resin obtained by further adding a compound having one epoxy group and one or more (meth) acryloyl groups in one molecule to the resins (1) to (11).
And so on.
In addition, in this specification, (meth) acrylate is a generic term for acrylate, methacrylate and a mixture thereof, and the same applies to other similar expressions.

The (A) carboxyl group-containing resin that can be used in the present invention is not limited to those listed above. Also. As the above-listed (A) carboxyl group-containing resin, one type may be used alone, or a plurality of types may be mixed and used. Among those listed above, a carboxyl group-containing resin synthesized by using a compound having a phenolic hydroxyl group as a starting material, such as the carboxyl group-containing resins (10) and (11), can be preferably used.

In the present invention, considering the developability, resolution, and drawability of the resist pattern when a weak alkaline developer such as an aqueous sodium carbonate solution is used, the acid value of the (A) carboxyl group-containing resin is 50 to 200 mgKOH / g. The range is preferably in the range of 45 to 120 mgKOH / g, more preferably in the range of 45 to 120 mgKOH / g. (A) The higher the acid value of the carboxyl group-containing resin, the better the developability and resolution, but the dissolution of the exposed part by the developing solution progresses, so the exposed part and the unexposed part are dissolved and peeled off by the developing solution. May be done.

The weight average molecular weight of the carboxyl group-containing resin (A) varies depending on the resin skeleton, but is generally in the range of 2,000 to 150,000, preferably in the range of 5,000 to 100,000. By using the (A) carboxyl group-containing resin having a weight average molecular weight of 2,000 or more, the resolution and tack-free performance can be improved. Further, by using the (A) carboxyl group-containing resin having a weight average molecular weight of 150,000 or less, developability, resolution and storage stability can be improved.

The blending amount of the carboxyl group-containing resin (A) is preferably 40 to 80% by mass with respect to the total amount of the photoresist composition containing the volatile matter. The strength of the cured film can be improved by setting the content to 40% by mass or more. Further, when the content is 80% by mass or less, the viscosity of the photoresist composition becomes appropriate and the processability is improved. A more preferable blending amount is 50 to 75% by mass, and a more preferable blending amount is 50 to 70% by mass.

<(B) Photopolymerizable monomer>
The (B) photopolymerizable monomer contained in the photoresist composition of the present invention is a monomer having an ethylenically unsaturated double bond. Examples of the photopolymerizable monomer include commonly known polyester (meth) acrylate, polyether (meth) acrylate, urethane (meth) acrylate, carbonate (meth) acrylate, and epoxy (meth) acrylate. Specifically, hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate; diacrylates of glycols such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol and propylene glycol; N, N-dimethylacrylamide. , N-methylol acrylamide, acrylamides such as N, N-dimethylaminopropyl acrylamide; aminoalkyl acrylates such as N, N-dimethylaminoethyl acrylate, N, N-dimethylaminopropyl acrylate; Polyhydric alcohols such as pentaerythritol, dipentaerythritol, tris-hydroxyethyl isocyanurate or polyhydric acrylates such as their ethireoxyside adducts, propylene oxide adducts, or ε-caprolactone adducts; phenoxyacrylates, bisphenol A di. Acrylate and polyvalent acrylates such as ethylene oxide adducts or propylene oxide adducts of these phenols; Polyvalent acrylates; Not limited to the above, acrylates and melamine acrylates obtained by directly acrylated polyols such as polyether polyols, polycarbonate diols, hydroxyl group-terminated polybutadienes, and polyester polyols, or urethane acrylates via diisocyanates, and the acrylates. It can be appropriately selected and used from at least one of each methacrylate corresponding to the above. Such a photopolymerizable monomer can also be used as a reactive diluent.

An epoxy acrylate resin obtained by reacting a polyfunctional epoxy resin such as cresol novolac type epoxy resin with acrylic acid, and a hydroxy acrylate such as pentaerythritol triacrylate and a diisocyanate half urethane such as isophorone diisocyanate on the hydroxyl group of the epoxy acrylate resin. An epoxy urethane acrylate compound obtained by reacting the compound or the like may be used as the photopolymerizable monomer. Such an epoxy acrylate-based resin can improve the photocurability without lowering the dryness to the touch.

The blending amount of the photopolymerizable monomer is preferably 10 to 40 parts by mass and more preferably 15 to 25 parts by mass with respect to 100 parts by mass of the varnish of the (A) carboxy-containing resin. By setting the blending amount of the photopolymerizable monomer to 10 parts by mass or more, the photocurability of the photoresist composition is improved. Further, by setting the blending amount to 40 parts by mass or less, the resolution of the cured film can be improved.

When a carboxyl group-containing non-photosensitive resin having no ethylenically unsaturated double bond is used as the photopolymerizable monomer, it is necessary to use the photopolymerizable monomer in combination in order to make the composition photocurable. Therefore, it is effective.

<(C) Thermosetting component>
The (C) thermosetting component contained in the photoresist composition of the present invention improves the barrier property (for example, etching resistance, etc.) of the cured film in a subsequent process, and has a high level of resolution and peelability. Can be compatible with. Any known thermosetting component can be used. For example, amino resins such as melamine resin, benzoguanamine resin, melamine derivative, benzoguanamine derivative, isocyanate compounds, blocked isocyanate compounds, cyclocarbonate compounds, epoxy compounds, oxetane compounds, episulfide resins, bismaleimide, carbodiimide resins and the like are used. it can. Particularly preferably, a compound having a plurality of cyclic ether groups or cyclic thioether groups (hereinafter, abbreviated as cyclic (thio) ether groups) in the molecule can be used. These thermosetting components may be used alone or in combination of two or more.

The compound having a plurality of cyclic (thio) ether groups in the molecule is a compound having a plurality of 3, 4, or 5-membered ring cyclic (thio) ether groups in the molecule, and is, for example, a plurality of epoxys in the molecule. Examples thereof include a compound having a group, that is, a polyfunctional epoxy compound, a compound having a plurality of oxetanyl groups in the molecule, that is, a polyfunctional oxetane compound, and a compound having a plurality of thioether groups in the molecule, that is, an episulfide resin.

Examples of such epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol S type epoxy resin, and phenol novolac type epoxy resin. Examples thereof include cresol novolac type epoxy resin, bisphenol A novolak type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, and triphenylmethane type epoxy resin.

Examples of commercially available epoxy resins include jER 828, 806, 807, YX8000, YX8034, 834 manufactured by Mitsubishi Chemical Corporation, and YD-128, YDF-170, ZX-1059 manufactured by Nippon Steel Chemical & Materials Co., Ltd. Examples thereof include ST-3000, EPICLON 830, 835, 840, 850, N-730A, N-695 manufactured by DIC Corporation, and RE-306 manufactured by Nippon Kayaku Co., Ltd.

Examples of the polyfunctional oxetane compound include bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl] ether, and 1,4-bis [(3-3-oxythenylmethoxy) methyl] ether. Methyl-3-oxetanylmethoxy) methyl] benzene, 1,4-bis [3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) ) Methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate and polyfunctional oxetane such as oligomers or copolymers thereof, as well as oxetane alcohol and novolak resin, Examples thereof include poly (p-hydroxystyrene), cardo-type bisphenols, calix arrayes, calix resorcinarenes, ether compounds with a resin having a hydroxyl group such as silsesquioxane, and the like. In addition, a copolymer of an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate can also be mentioned.

Examples of the compound having a plurality of cyclic thioether groups in the molecule include bisphenol A type episulfide resin and the like. Further, using the same synthesis method, an episulfide resin in which the oxygen atom of the epoxy group of the novolak type epoxy resin is replaced with a sulfur atom can also be used.

Examples of amino resins such as melamine derivatives and benzoguanamine derivatives include methylol melamine compounds, methylol benzoguanamine compounds, methylol glycol uryl compounds and methylol urea compounds.

As the isocyanate compound, a polyisocyanate compound can be blended. Polyisocyanate compounds include 4,4'-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,5-diisocyanate, o-xylylene diisocyanate, m-xylylene diisocyanate and Aromatic polyisocyanates such as 2,4-tolylene dimer; aliphatic polyisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4-methylenebis (cyclohexyl isocyanate) and isophorone diisocyanate; bicyclo Alicyclic polyisocyanates such as heptanthriisocyanate; and adducts, burettes, and isocyanurates of the isocyanate compounds mentioned above can be mentioned.

As the blocked isocyanate compound, an addition reaction product of the isocyanate compound and the isocyanate blocking agent can be used. Examples of the isocyanate compound capable of reacting with the isocyanate blocking agent include the above-mentioned polyisocyanate compound and the like. Examples of the isocyanate blocking agent include phenol-based blocking agents; lactam-based blocking agents; active methylene-based blocking agents; alcohol-based blocking agents; oxime-based blocking agents; mercaptan-based blocking agents; acid amide-based blocking agents; imide-based blocking agents; Amine-based blocking agents; imidazole-based blocking agents; imine-based blocking agents and the like can be mentioned.

The amount of the (C) thermosetting component blended is preferably 0.8 to 2.5 mol of the number of functional groups of the thermosetting component that reacts with respect to 1.0 mol of the carboxyl group contained in the (A) carboxyl group-containing resin. , More preferably 1.0 to 2.0 mol.

In particular, when an epoxy resin is used as the (C) thermosetting component, the epoxy group of the epoxy resin is preferably 1.0 to 2.0 mol per 1.0 mol of the carboxyl group of the carboxyl group-containing resin. By setting the amount to 1 mol or more, it is possible to prevent the residue of carboxyl groups in the cured film and obtain good heat resistance, alkali resistance, electrical insulation and the like. Further, by setting the blending amount to 2 mol or less, it is possible to prevent low molecular weight cyclic (thio) ether groups from remaining in the dry coating film and to ensure good strength of the cured film.

The photoresist composition of the present invention preferably contains (D) a photopolymerization initiator for reacting the above-mentioned (A) carboxyl group-containing resin and (B) photopolymerizable monomer by exposure. Any known photopolymerization initiator can be used. As the photopolymerization initiator, one type may be used alone, or two or more types may be used in combination.

Specific examples of the photopolymerization initiator include bis- (2,6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, and bis. -(2,6-dichlorobenzoyl) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis- (2,6-dimethoxybenzoyl) phenylphosphine oxide , Bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, Bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, Bis- (2, Bisacylphosphine oxides such as 4,6-trimethylbenzoyl) -phenylphosphine oxide; 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethyl Monoacylphosphine oxides such as benzoylphenylphosphinic acid methyl ester, 2-methylbenzoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid isopropyl ester, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; phenyl ( 2,4,6-trimethylbenzoyl) ethyl phosphinate, 1-hydroxy-cyclohexylphenylketone, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propane-1- On, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one, 2-hydroxy-2-methyl-1 Hydroxyacetophenones such as −phenylpropan-1-one; benzoins such as benzoin, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether; benzoin alkyl ethers; benzophenone , P-Methylbenzophenone, Michler's ketone, Methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone and other benzophenones; acetophenone, 2,2-dimethoxy-2-phenyla Setophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenylketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2- (dimethylamino) -2-[(4-methylphenyl) methyl) -1- [4- (4- (4- (4-) Morphorinyl) phenyl] -1-butanone, N, N-dimethylaminoacetophenone and other acetophenones; thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chloro Thioxanthones such as thioxanthone and 2,4-diisopropylthioxanthone; anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylantraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone and the like. Anthraquinones; Ketals such as acetophenone dimethyl ketal, benzyl dimethyl ketal; benzoic acid esters such as ethyl-4-dimethylaminobenzoate, 2- (dimethylamino) ethyl benzoate, p-dimethylbenzoic acid ethyl ester; 1,2 -Octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], etanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] Oxime esters such as-, 1- (O-acetyloxime); bis (η5-2,4-cyclopentadiene-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole-1-yl) ) Oxime) Titanium, bis (cyclopentadienyl) -bis [2,6-difluoro-3- (2- (1-pyr-1-yl) ethyl) phenyl] Titanocenes such as titanium; phenyldisulfide 2-nitro Examples thereof include fluorene, butyloin, anisoin ethyl ether, azobisisobutyronitrile, tetramethylthiuram disulfide and the like.

Examples of commercially available α-aminoacetophenone-based photopolymerization initiators include Omnirad 907, 369, 369E, and 379 manufactured by IGM Resins. Examples of commercially available acylphosphine oxide-based photopolymerization initiators include Omnirad TPO and 819 manufactured by IGM Resins. Commercially available oxime ester-based photopolymerization initiators include Irgacure OXE01 and OXE02 manufactured by BASF Japan Ltd., N-1919 manufactured by ADEKA Corporation, Adeca Arcurus NCI-831, NCI-831E, and Changzhou Powerful Electronics New Materials Co., Ltd. TR-PBG-304 and the like can be mentioned.

In addition, JP-A-2004-359639, JP-A-2005-097141, JP-A-2005-22097, JP-A-2006-160634, JP-A-2008-09470, JP-A-2008-50967, Examples thereof include carbazole oxime ester compounds described in JP-A-2009-040762 and JP-A-2011-80036.

The blending amount of the photopolymerization initiator is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the varnish of the (A) carboxyl group-containing resin. When the amount is 1 part by mass or more, the photocurability of the resin composition is good, and the coating properties such as chemical resistance are also good. Further, when the amount is 20 parts by mass or less, the effect of reducing outgas is obtained, the light absorption on the surface of the resist film (cured film) is good, and the deep curability is unlikely to be lowered. More preferably, it is 2 to 7 parts by mass.

A photoinitiator or sensitizer may be used in combination with the above-mentioned (D) photopolymerization initiator. Examples of the photoinitiator aid or sensitizer include benzoin compounds, anthraquinone compounds, thioxanthone compounds, ketal compounds, benzophenone compounds, tertiary amine compounds, and xanthone compounds. In particular, it is preferable to use thioxanthone compounds such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, and 4-isopropylthioxanthone. By containing the thioxanthone compound, the deep curability can be improved. Although these compounds may be used as a photopolymerization initiator, they are preferably used in combination with a photopolymerization initiator. In addition, one type of photoinitiator aid or sensitizer may be used alone, or two or more types may be used in combination.

Since these photopolymerization initiators, photoinitiator aids, and sensitizers absorb specific wavelengths, their sensitivity may be lowered in some cases, and they may function as ultraviolet absorbers. However, these are not used only for the purpose of improving the sensitivity of the resin composition. It absorbs light of a specific wavelength as needed to enhance the photoreactivity of the surface, change the line shape and aperture of the resist pattern to vertical, tapered, or reverse tapered, and the accuracy of the line width and aperture diameter. Can be improved.

<(E) Thermosetting catalyst>
The photoresist composition of the present invention may contain a thermosetting catalyst for accelerating the curing of the above-mentioned (C) thermosetting component. Examples of the thermosetting catalyst include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-. Imidazole derivatives such as (2-cyanoethyl) -2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethylbenzyl Examples thereof include amine compounds such as amine, 4-methyl-N and N-dimethylbenzylamine, hydrazine compounds such as adipic acid dihydrazide and sebacic acid dihydrazide; and phosphorus compounds such as triphenylphosphine. Commercially available products include, for example, 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (both are trade names of imidazole compounds) manufactured by Shikoku Kasei Kogyo Co., Ltd., and U-CAT manufactured by San Apro Co., Ltd. Examples thereof include 3513N (trade name of a dimethylamine compound), DBU, DBN, and U-CAT SA 102 (all of which are bicyclic amidine compounds and salts thereof).

The compound is not limited to the above-mentioned compounds, and may be a thermosetting catalyst of an epoxy resin or an oxetane compound, or one that promotes the reaction of at least one of an epoxy group and an oxetanyl group with a carboxyl group, either alone or 2 Seeds or more may be mixed and used. In addition, guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino S-triazine derivatives such as -S-triazine-isocyanuric acid adduct and 2,4-diamino-6-methacryloyloxyethyl-S-triazine-isocyanulic acid adduct can also be used, preferably as these adhesion-imparting agents. A compound that also functions is used in combination with a thermosetting catalyst.

The above-mentioned (E) thermosetting catalyst may be used alone or in combination of two or more. (E) The blending amount of the thermosetting catalyst is 0.01 to 5 parts by mass with respect to 100 parts by mass of the varnish of the carboxyl group-containing resin from the viewpoint of storage stability of the resin composition and heat resistance of the cured film. Is preferable, and is more preferably 0.05 to 1 part by mass.

<Other ingredients>
The photoresist composition of the present invention may contain a filler, if necessary, in order to increase the physical strength of the cured film. As the filler, known inorganic or organic fillers can be used, but barium sulfate, spherical silica, hydrotalcite and talcite are particularly preferably used. Further, in order to obtain flame retardancy, a metal oxide, a metal hydroxide such as aluminum hydroxide, or the like can be used as an extender pigment filler.

Among the above-mentioned fillers, spherical silica can be preferably used. As the spherical silica, it is preferable to use spherical silica having an average particle size of 1 nm to 100 nm, more preferably the average particle size is 1 nm to 50 nm, and further preferably the average particle size is 2 nm to 50 nm. The surface states Ra1 and Ra2 of the cured film can also be adjusted by blending spherical silica having an average particle size as described above. The average particle size is the average particle size (D50) including not only the particle size of the primary particles but also the particle size of the secondary particles (aggregates), and is the value of D50 measured by the laser diffraction method. is there. The average particle size can be determined using a measuring device by a laser diffraction method (for example, Microtrac MT3300EXII manufactured by Microtrac Bell Co., Ltd.).

The blending amount of the filler is not particularly limited, but is preferably 30% by mass or less, preferably 0 to 15% by mass, based on the total amount of the resin composition from the viewpoint of viscosity, coatability, moldability and the like. More preferably.

Further, the above-mentioned filler may be surface-treated in order to enhance the dispersibility in the photoresist composition. Aggregation can be suppressed by using a filler that has been surface-treated. The surface treatment method is not particularly limited, and a known and commonly used method may be used. However, the surface of the inorganic filler may be treated with a surface treatment agent having a curable reactive group, for example, a coupling agent having a curable reactive group as an organic group. It is preferable to treat it.

As the coupling agent, a silane-based, titanate-based, aluminate-based, zircoaluminate-based coupling agent or the like can be used. Of these, a silane coupling agent is preferable. Examples of such silane coupling agents include vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminomethyl) -3-aminopropylmethyldimethoxysilane, and N- (2-aminoethyl) -3-amino. Propyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-anilinopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxy) Cyclohexyl) ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane and the like can be mentioned, and these can be used alone or in combination. These silane-based coupling agents are preferably immobilized on the surface of the filler in advance by adsorption or reaction. Here, the treatment amount of the coupling agent with respect to 100 parts by mass of spherical silica is preferably 0.5 to 10 parts by mass.

The photoresist composition of the present invention may contain a colorant, if necessary. As the colorant, known colorants such as red, blue, green, and yellow can be used, and any of pigments, dyes, and pigments may be used, but halogens are used from the viewpoint of reducing the environmental load and having little effect on the human body. It is preferable that the colorant does not contain.

Examples of red colorants include monoazo, disazo, azolake, benzimidazolone, perylene, diketopyrrolopyrrole, condensed azo, anthraquinone, quinacridone, etc. -Indexed (CI; issued by The Society of Dyersand Colorists).

Examples of monoazo red colorants include Pigment Red 1,2,3,4,5,6,8,9,12,14,15,16,17,21,22,23,31,32,112,114, 146,147,151,170,184,187,188,193,210,245,253,258,266,267,268,269 and the like can be mentioned.
Examples of the disazo-based red colorant include Pigment Red 37, 38, 41 and the like.
Further, as a monoazolake-based red colorant, Pigment Red 48: 1,48: 2,48: 3,48: 4,49: 1,49: 2,50: 1,52: 1,52: 2,53: Examples thereof include 1,53: 2,57: 1,58: 4,63: 1,63: 2,64: 1,68.
Examples of the benzimidazolone-based red colorant include Pigment Red 171, 175, 176, 185, 208 and the like.
Examples of the perylene-based red colorant include Solvent Red 135,179, Pigment Red 123, 149, 166, 178, 179, 190, 194, 224 and the like.
Examples of the diketopyrrolopyrrole red colorant include Pigment Red 254, 255, 264, 270, 272 and the like.
Examples of the condensed azo red colorant include Pigment Red 220, 144, 166, 214, 220, 221, 242 and the like.
Examples of the anthraquinone-based red colorant include Pigment Red 168, 177, 216 and Solvent Red 149, 150, 52, 207.
Examples of the quinacridone-based red colorant include Pigment Red 122, 202, 206, 207, 209 and the like.

Examples of the blue colorant include phthalocyanine-based and anthraquinone-based compounds, and pigment-based compounds include compounds classified as Pigment. For example, Pigment Blue 15,15: 1,15: 2,15: 3,15: 4,15: 6,16,60. As the dye system, Solvent Blue 35, 63, 68, 70, 83, 87, 94, 97, 122, 136, 67, 70 and the like can be used. In addition to the above, metal-substituted or unsubstituted phthalocyanine compounds can also be used.

Examples of the yellow colorant include monoazo, disazo, condensed azo, benzimidazolone, isoindolinone, anthraquinone, and the like. For example, the anthraquinone yellow colorant includes Solvent Yellow 163, Pigment Yellow 24, 108, 193, 147, 199, 202 and the like can be mentioned.
Examples of the isoindolinone-based yellow colorant include Pigment Yellow 110, 109, 139, 179, 185 and the like.
Examples of the condensed azo yellow colorant include Pigment Yellow 93, 94, 95, 128, 155, 166, 180 and the like.
Examples of the benzimidazolone-based yellow colorant include Pigment Yellow 120, 151, 154, 156, 175, 181 and the like.
In addition, as a monoazo yellow colorant, Pigment Yellow 1,2,3,4,5,6,9,10,12,61,62,62: 1,65,73,74,75,97,100, 104, 105, 111, 116, 167, 168, 169, 182, 183 and the like can be mentioned.
Examples of the disazo-based yellow colorant include Pigment Yellow 12, 13, 14, 16, 17, 55, 63, 81, 83, 87, 126, 127, 152, 170, 172, 174, 176, 188, 198 and the like. Can be mentioned.

In addition, colorants such as purple, orange, brown, black, and white may be added. Specifically, Pigment Black 1,6,7,8,9,10,11,12,13,18,20,25,26,28,29,30,31,32, Pigment Violet 19, 23, 29 , 32, 36, 38, 42, Solvent Violet 13, 36, C.I. I. Pigment Orange 1,5,13,14,16,17,24,34,36,38,40,43,46,49,51,61,63,64,71,73, PigmentBrown 23,25, Carbon Black, Examples include titanium oxide.

The amount of the colorant to be blended in the photoresist composition is not particularly limited, but may be 0 to 5 parts by mass with respect to 100 parts by mass of the varnish of the carboxyl group-containing resin.

The photoresist composition of the present invention may contain an organic solvent from the viewpoint of ease of preparation and coatability. Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethyl benzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol and propylene glycol monomethyl ether. , Dipropylene glycol monomethyl ether, Dipropylene glycol diethyl ether, Diethylene glycol monomethyl ether acetate, Tripropylene glycol monomethyl ether and other glycol ethers; Ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbi Esters such as tall acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, and solvent naphtha are known. Conventional organic solvents can be used. These organic solvents may be used alone or in combination of two or more.

Further, if necessary, the photoresist composition of the present invention includes an elastomer, a mercapto compound, a urethanization catalyst, a thixotropic agent, an adhesion accelerator, a block copolymer, a chain transfer agent, a polymerization inhibitor, a copper damage inhibitor, and the like. Antioxidants, rust preventives, thickeners such as organic bentonite and montmorillonite, at least one of silicone-based, fluorine-based, polymer-based defoaming agents and leveling agents, phosphinates, phosphate ester derivatives, Ingredients such as flame retardants such as phosphorus compounds such as phosphazene compounds can be blended. As these, those known in the field of electronic materials can be used.

[Dry film]
In the present invention, in addition to the method of directly applying the liquid photoresist composition to the base material, a dry film having a resin layer formed by previously applying the photoresist composition to a support film such as polyethylene terephthalate and drying it. It can also be used in the form. The case where the photoresist composition of the present invention is used as a dry film will be described below.

The dry film has a structure in which a support film, a resin layer, and a peelable protective film used as needed are laminated in this order. The resin layer is a layer obtained by applying the photoresist composition of the present invention to a support film or a protective film and drying it. A dry film can be obtained by forming a resin layer on the support film and then laminating a protective film on the protective film, or by forming a resin layer on the protective film and laminating this laminate on the support film.

In the case of a dry film, the photoresist composition is diluted with the above organic solvent to adjust the viscosity to an appropriate level, and a comma coater, blade coater, lip coater, rod coater, squeeze coater, reverse coater, transfer coater, and gravure coater are used. , A spray coater or the like is applied onto a carrier film to a uniform thickness, and the film is usually dried at a temperature of 60 to 90 ° C. for 1 to 40 minutes to obtain a film. The coating film thickness is not particularly limited, but in general, the film thickness after drying is preferably 150 μm or less, and more preferably 1 to 15 μm.

As the support film, any known one can be used without particular limitation. For example, a polyester film such as polyethylene terephthalate or polyethylene naphthalate, a polyimide film, a polyamideimide film, a polypropylene film, a thermoplastic resin such as a polystyrene film or the like can be used. A film made of the above can be preferably used. Among these, a polyester film is preferable from the viewpoint of heat resistance, mechanical strength, handleability and the like. Further, a laminate of these films can also be used as a support film.

The thermoplastic resin film as described above is preferably a film stretched in the uniaxial direction or the biaxial direction from the viewpoint of improving the mechanical strength.

The thickness of the support film is not particularly limited, but can be, for example, 10 μm to 150 μm.

As the protective film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper, or the like can be used, and when the protective film is peeled off, the resin layer is more than the adhesive force between the resin layer and the support film. It suffices if the adhesive strength between the film and the protective film is smaller.

The thickness of the protective film is not particularly limited, but can be, for example, 10 μm to 150 μm.

To form a cured film on a base material as described later using a dry film, peel off the protective film from the dry film, overlay the exposed resin layer of the dry film on the base material, and bond them together using a laminator or the like. , A resin layer is formed on the base material. Then, if the formed resin layer is exposed and developed, a cured film can be formed by photocuring at the time of exposure.

The photoresist composition of the present invention may be used as a dry film as described above, or may be used in a liquid state. When used as a liquid, it may be one-component or two-component or more. In particular, from the viewpoint of storage stability, it is preferable to use two liquids. In the case of two liquids, the above-mentioned (A) carboxyl group-containing resin and (D) photopolymerization initiator and other components may be blended in the same formulation or in different formulations.

[Cured product]
By curing the photoresist composition of the present invention, a cured product such as a cured film can be obtained. The photoresist composition of the present invention can be widely used in semiconductor applications such as integrated circuits, and can be suitably used as a semi-permanent coating, that is, peeling during manufacturing.

Examples of the base material on which the cured film is formed include a wafer substrate, a glass substrate, a metal substrate, a polyimide film, a polyethylene terephthalate film, a polyethylene naphthalate (PEN) film, and a ceramic substrate. Of these, a wafer substrate and a glass substrate are preferable from the viewpoint of substrate flatness. Among the wafer substrates, a silicon wafer substrate is preferable. On the other hand, among the glass substrates, non-alkali glass substrates such as Corning (registered trademark) EAGLE XG (registered trademark) Slim are preferable.

It is preferable that the dry film is attached to the substrate under pressure and heating using a vacuum laminator or the like. By using such a vacuum laminator, when a circuit-formed substrate is used, even if the surface of the circuit board is uneven, the dry film adheres to the circuit board, so that no air bubbles are mixed in and the circuit board is not mixed. The hole filling property of the recesses on the surface of the substrate is also improved. The pressurizing condition is preferably about 0.1 to 2.0 MPa, and the heating condition is preferably 40 to 120 ° C. for 1 to 5 minutes.

The volatile drying (pre-baking) performed after applying the photoresist composition of the present invention is performed by using a hot air circulation type drying furnace, an IR furnace, a hot plate, a convection oven, or the like (using a steam-based air heating type heat source). This can be done by using a method in which hot air in the machine is brought into countercurrent contact and a method in which the hot air is blown onto the support from a nozzle). Pre-baking is usually carried out at a temperature of 80 ° C. for about 20 to 40 minutes. A tack-free coating film (resin layer) can be formed by prebaking. Further, in the case of a dry film, the resin layer is formed on the base material by sticking it on the base material with a laminator or the like so that the resin layer comes into contact with the base material, and then peeling off the support film.

After forming a resin layer on the substrate, it is selectively exposed to ultraviolet rays 1 through a photomask having a predetermined pattern formed, and the unexposed portion is exposed to a dilute alkaline aqueous solution (for example, 0.3 to 3 mass% sodium carbonate aqueous solution). Develop for 30-300 seconds to form a cured product pattern. In the case of a dry film, after exposure, the support film is peeled off from the dry film and developed to form a patterned cured product on the substrate. The exposed resin layer may be exposed and developed by peeling the support film from the dry film before exposure as long as the characteristics are not impaired. Further, in the present invention, when confirming whether or not Ra2 / Ra1 of the dry film falls within a predetermined range (≦ 4.5 × 10 ^-1 ), a resin layer having a film thickness of 2 μm ± 0.5 μm is used. , Confirmed according to the photoresist composition of the present invention, but the support film shall be peeled off before exposure.

The exposure machine used for irradiating ultraviolet light 1 may be a device equipped with a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a mercury short arc lamp, etc., and irradiating ultraviolet light 1 in the range of 350 to 450 nm. Further, a direct drawing device (for example, a laser direct imaging device that directly draws an image with a laser based on CAD data from a computer) can also be used. The lamp light source or the laser light source of the direct drawing machine may have a maximum wavelength in the range of 350 to 450 nm. The amount of exposure for image formation and photocuring varies depending on the film thickness and the like, but can generally be in the range of ^{10 to 2,000 mJ / cm 2} , preferably 20 to 1,500 mJ / cm ^2. Further, the exposure is preferably performed in an atmospheric atmosphere.

The developing method can be a dipping method, a shower method, a spray method, a brush method, etc., and the developing solution includes potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, and ammonia. , Alkaline aqueous solutions such as amines can be used, but the photoresist composition of the present invention is particularly high even when developed using a weak alkaline aqueous solution such as sodium carbonate or potassium carbonate having a pH of 11.6 or less. Fine patterning of resolution is obtained.

After developing the resin layer, if necessary, heat treatment (post-baking) may be performed within a range that does not impair the characteristics. The temperature and time of the heat treatment performed after the development depends on the composition of the photoresist composition constituting the resin layer, but can be, for example, 90 ° C. for 20 minutes or less.

After undergoing the pre-baking, exposure and development, and optionally post-baking steps as described above, it is preferable to further expose the cured product with ultraviolet rays (ultraviolet rays 2) having a wavelength shorter than that at the time of exposure. Further exposure using ultraviolet rays 2 can crosslink the monomer components remaining in the cured product and decompose the polymer. For cross-linking of residual monomers and decomposition of polymers, for example, UV ozone cleaner (distance from UV lamp light source to irradiation surface is 1 cm, type: low-pressure mercury lamp (fused quartz), shape: high-density high-power grid type lamp, ultraviolet rays It can be carried out by irradiating the cured product with ultraviolet rays 2 (for example, 185 nm and 254 nm) having a wavelength shorter than that of the above-mentioned ultraviolet rays 1 by using an apparatus such as intensity: 28 mW / cm ^2). By further exposing the cured product that has been exposed and developed with ultraviolet rays 1 using ultraviolet rays 2, the cured product can be easily peeled from the base, and the peelability is improved. The exposure using the ultraviolet rays 2 is preferably performed in an oxygen atmosphere. The maximum temperature at the time of exposure using ultraviolet rays 2 is preferably in the range of 80 to 200 ° C, more preferably in the range of 100 to 150 ° C.

As the peeling method, a dipping method, a spraying method, a method using a single-wafer method or the like can be used, the peeling temperature is 40 to 60 ° C., and the stripping solution is an N-methylpyrrolidone solution or the like.

The photoresist composition of the present invention can be suitably used for microfabrication by lithography in the manufacturing process of semiconductor devices such as ICs (integrated circuits) and LSIs (large-scale integrated circuits). For example, it can be used in a forming process such as rewiring of a wafer level package. Specifically, a patterned resist layer is formed on a UBM layer (bump base metal) of a substrate such as a silicone substrate in an LSI chip by using a photoresist composition. Copper wiring plating is performed on the part where the patterned resist layer is not applied. After that, the resist layer is peeled off to form a rewiring layer. However, this is just an example, and the present invention is not limited to this.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but it goes without saying that the present invention is not limited to the following Examples. In the following, "part" and "%" are all based on mass unless otherwise specified.

<Synthesis example 1>
In an autoclave equipped with a thermometer, a nitrogen introduction device and an alkylene oxide introduction device, and a stirring device, 119.4 g of novolak type cresol resin (manufactured by Aika Kogyo Co., Ltd., trade name "Shonol CRG951", OH equivalent: 119.4), 1.19 g of potassium hydroxide and 119.4 g of toluene were charged, the inside of the system was replaced with nitrogen while stirring, and the temperature was raised by heating. Next, 63.8 g of propylene oxide was gradually added dropwise, and the mixture was reacted at ^{125 to 132 ° C. and 0 to 4.8 kg / cm 2 for 16 hours.} Then, the mixture was cooled to room temperature, and 1.56 g of 89% phosphoric acid was added to and mixed with this reaction solution to neutralize potassium hydroxide, and the non-volatile content was 62.1% and the hydroxyl value was 182.2 g / eq. A propylene oxide reaction solution of the novolak type cresol resin was obtained. This had an average of 1.08 mol of alkylene oxide added per equivalent of phenolic hydroxyl group. Next, 293.0 g of an alkylene oxide reaction solution of the obtained novolak-type cresol resin, 43.2 g of acrylic acid, 11.53 g of methanesulfonic acid, 0.18 g of methylhydroquinone and 252.9 g of toluene were added to a stirrer, a thermometer and air. The mixture was charged into a reactor equipped with a blowing tube, air was blown at a rate of 10 ml / min, and the reaction was carried out at 110 ° C. for 12 hours with stirring. As for the water produced by the reaction, 12.6 g of water was distilled off as an azeotropic mixture with toluene. Then, the mixture was cooled to room temperature, the obtained reaction solution was neutralized with 35.35 g of a 15% aqueous sodium hydroxide solution, and then washed with water. Then, toluene was distilled off while substituting 118.1 g of diethylene glycol monoethyl ether acetate with an evaporator to obtain a novolak type acrylate resin solution. Next, 332.5 g of the obtained novolak-type acrylate resin solution and 1.22 g of triphenylphosphine were charged into a reactor equipped with a stirrer, a thermometer and an air blowing tube, and air was blown at a rate of 10 ml / min. , 60.8 g of tetrahydrophthalic anhydride was gradually added with stirring, and the mixture was reacted at 95 to 101 ° C. for 6 hours. In this way, a resin solution of a carboxyl group-containing photosensitive resin having a solid acid value of 88 mgKOH / g, a solid content of 71%, and a weight average molecular weight of 2,000 was obtained. This is referred to as a carboxyl group-containing resin varnish 1.

<Synthesis example 2>
848.8 g of GBL (gamma butyrolactone), 57.5 g (0.23 mol) of MDI (diphenylmethane diisocyanate), DMBPDI (4,4'-diisocyanate-3,3'" in a flask equipped with a stirrer, a thermometer and a condenser. -Dimethyl-1,1'-biphenyl) 59.4 g (0.225 mol), TMA (trimellitic anhydride) 67.2 g (0.35 mol) and TMA-H (cyclohexane-1,3,4-tricarboxylic acid) Add 29.7 g (0.15 mol) of acid-3,4-anhydrous), raise the temperature to 80 ° C while paying attention to heat generation while stirring, dissolve and react at this temperature for 1 hour, and further. After raising the temperature to 160 ° C. over 2 hours, the reaction was carried out at this temperature for 5 hours. The reaction proceeded with the foaming of carbon dioxide gas, and the inside of the system became a brown transparent liquid. In this way, a solution of a carboxyl group-containing amidimide resin having a viscosity of 7 Pa · s at 25 ° C. and a solid content of 17% and a solution acid value of 5.3 (KOH mg / g) (a resin in which the resin is dissolved in γ-butyrolactone). Composition) was obtained. The solid acid value of the resin was 31.2 (KOHmg / g), and the weight average molecular weight was 34,000. This is referred to as a carboxyl group-containing resin varnish 2.

<Preparation of photoresist composition>
The components shown in Table 1 below were blended in the proportions (parts by mass) shown in Table 1 below, premixed with a stirrer, and kneaded with a three-roll mill to prepare each photoresist composition. Each component * 1 to * 8 in Table 1 is as follows. The amount of the carboxyl group-containing resin varnish in the table is the amount of the varnish, and the amount of the filler is the total amount of the solid content and the volatile components.

* 1: Carboxyl group-containing resin varnish 1 (solid content 71%) obtained in Synthesis Example 1
* 2: Carboxyl group-containing resin varnish 2 (solid content 17%) obtained in Synthesis Example 2
* 3: 2,4,6-trimethylbenzoyldiphenylphosphine oxide (Omnirad TPO, manufactured by IGM Resins)
* 4: Tricyclodecanedimethanol diacrylate (A-DCP, manufactured by Shin-Nakamura Kogyo Co., Ltd.)
* 5: Dipentaerythritol hexaacrylate (A-DPH, manufactured by Shin-Nakamura Kogyo Co., Ltd.)
* 6: Bisphenol A type epoxy resin (jER 828, manufactured by Mitsubishi Chemical Corporation)
* 7: Imidazole epoxy resin curing agent (Curesol 1B2PZ, manufactured by Shikoku Chemicals Corporation)
* 8: Nanosilica fine particles (YA050C, manufactured by Admatex Co., Ltd., average particle size 50 nm)
* 9: Silica particles (SO-E6, manufactured by Admatex Co., Ltd., average particle size 1.8 to 2.3 μm)

<Preparation of cured film 1>
Each photoresist composition obtained as described above was placed on a 5 cm × 5 cm × 0.7 mmt glass substrate (Corning (registered trademark) EAGLE XG (registered trademark) Slim), and the thickness of the coating film after drying was increased. It was applied by a spin coating method so as to have a thickness of 2 ± 0.5 μm, dried in a hot air circulation type drying oven at 75 ° C. for 30 minutes, and prebaked. Next, a line pattern of L / S = 10/10, 7/7, 5/5, 4/4, 3/3, 2/2, 1/1 (all units are μm) is formed on the coating film. A metal halide lamp is used to irradiate ultraviolet rays 1 having a wavelength of 375 nm at ^{an exposure of 1,000 mJ / cm 2} _{in an atmospheric atmosphere, and then using a 1 wt% Na 2} CO ₃ aqueous solution at 30 ° C. The cured film 1 was formed by developing for 180 seconds.

JIS B0601: 2001 (ISO4287: ISO4287:) using a laser microscope VK-X series (manufactured by KEYENCE CORPORATION) compatible with the non-contact measurement method at any 10 locations on the surface of the cured coating film 1 obtained as described above. The arithmetic mean roughness Ra was measured according to 1997), and the average value was defined as Ra1 (nm). Specifically, the surface of the cured coating film 1 in the range of 200 μm × 200 μm was randomly measured at 10 points at a magnification of 100 times with a microscope, and the average value was taken.

<Preparation of cured film 2>
Subsequently, a UV ozone cleaner (distance from the UV lamp light source to the irradiation surface is 1 cm, type: low pressure mercury lamp (fused quartz), shape: high density high output grid type) is applied to the cured film 1 obtained as described above. ^{By irradiating ultraviolet rays 2} having a wavelength of 185 nm (10%) + 254 nm (90%) in an oxygen atmosphere with an exposure amount of 25.2 J / cm 2 using a device such as a lamp and ultraviolet intensity: 28 mW / cm ^2). A cured film 2 was formed.
The arithmetic average roughness Ra of the surface of the cured film 2 obtained as described above was measured in the same manner as in the cured film 1, and the average value was taken as R2 (nm).
The values of Ra1 of the cured film 1, Ra2 of the cured film 2, and Ra2 / Ra1 are as shown in Table 1 below. In Comparative Examples 1 and 2, measurement was not possible because fine patterns could not be formed (resolution evaluation) due to undevelopment.

<Surface hardness evaluation>
The surface hardness of the cured film 1 and the cured film 2 was measured according to JIS K 5400. The measurement results are as shown in Table 1 below. In Comparative Examples 1 and 2, since fine pattern formation was not possible due to development failure (resolution evaluation), no other evaluation was performed.

<Resolution evaluation>
The surface of the cured film 1 was observed with a microscope, and patterning evaluation was performed according to the following criteria.
◯: Fine pattern (L / S ≦ 10 μm) can be formed ×: Fine pattern (L / S ≦ 10 μm) cannot be formed The evaluation results are as shown in Table 1 below.

<Evaluation of peelability>
A cured film was formed on the silicon wafer substrate in the same manner as in the above-mentioned formation of the cured film 2 except that a silicon wafer substrate was used instead of the glass substrate. A silicon wafer substrate having a cured film formed on its surface is immersed in an N-methylpyrrolidone solution at 50 ° C. for 15 minutes, and then the adhesion between the silicon wafer substrate and the cured film is visually confirmed and peelable according to the following criteria. Was evaluated. The evaluation results are as shown in Table 1 below. In Comparative Examples 1 and 2, since fine pattern formation was not possible due to development failure (resolution evaluation), no other evaluation was performed.
◯: The cured film is completely peeled off from the substrate ×: A part of the cured film is attached to the substrate The evaluation results are as shown in Table 1 below.

As is clear from the results in Table 1, Examples 1 to 4 to which the curable resin composition in which the ratio of arithmetic mean roughness (Ra2 / Ra1) and the like satisfy the constitution of the present invention are applied are of resolvability. From the results, it can be seen that development is possible even with a weak alkaline developer, fine patterning with high resolution can be obtained, and peelability is also excellent. On the other hand, it can be seen that Comparative Examples 1 and 2 lacking the essential components of the present invention are inferior in resolution as compared with each of the examples. Further, it can be seen that Comparative Examples 3 and 4 in which the ratio of the arithmetic mean roughness (Ra2 / Ra1) does not satisfy the constitution of the present invention are inferior in peelability or resolution as compared with each example.

Claims (8)

(A) Carboxyl group-containing resin,
(B) photopolymerizable monomer and (C) thermosetting component,
A photoresist composition comprising
The photoresist composition is applied onto a flat substrate so that the cured film thickness is 2 μm ± 0.5 μm, and after prebaking at 75 ° C. for 30 minutes, ultraviolet rays 1 having a wavelength of 375 nm are applied to 1 in an air atmosphere. The surface of the cured film 1 formed by exposing to an exposure amount of 000 mJ / cm ² to cure the photoresist composition and then developing at 30 ° C. with a 1 wt% Na ₂ CO _{3 aqueous solution for 180 seconds.} Arithmetic mean roughness Ra is Ra1
The arithmetic average roughness Ra of the surface of the cured film 2 formed by further exposing the cured film 1 to ultraviolet rays 2 having wavelengths of 185 nm and 254 nm under an oxygen atmosphere at ^{an exposure amount of 25.2 J / cm 2 is Ra2.} When, the following formula:
Ra2 / Ra1 ≤ 4.5 × 10 ^-1
A photoresist composition, characterized in that it meets the requirements. The photoresist composition according to claim 1, wherein the (B) photopolymerizable monomer is at least one selected from (meth) acrylates. The photoresist composition according to claim 1 or 2, wherein the carboxyl group-containing resin (A) has an acid value of 50 to 200 mgKOH / g. The photoresist composition according to any one of claims 1 to 3, wherein the carboxyl group-containing resin (A) has a weight average molecular weight of 5,000 to 100,000. Ra2 / Ra1 ≤ 4.0 × 10 ^-1
The photoresist composition according to any one of claims 1 to 4, which satisfies the above conditions. Ra2 / Ra1 ≧ 1.9 × 10 ^-1
The photoresist composition according to any one of claims 1 to 5, which satisfies the above conditions. 1.9 x 10 ^-1 ≤Ra2 / Ra1≤4.0 x 10 ^-1
The photoresist composition according to any one of claims 1 to 6, which satisfies the above conditions. A cured product, which is obtained by curing the photoresist composition according to any one of claims 1 to 7.