KR100852380B1 - Method of forming plated product using negative photoresist composition and photosensitive composition used therein - Google Patents

Abstract

A method is provided for enabling the formation of multi-stage plated articles with large plating depths. A negative photoresist composition comprising (a) an alkali-soluble resin, (b) an acid generator and (C) other components is used, and the plated article is (A) not heated or heated before exposure after layer formation of the negative photoresist composition. Does not step; (B) repeating step (A) so that step (A) is performed a total of two or more times, stacking layers of negative photoresist and subsequently developing all of these layers simultaneously to form a multilayer resist pattern; And (C) plating in such a multilayer resist pattern.

Description

Method of forming plated product using negative photoresist composition and photosensitive composition used therein {METHOD OF FORMING PLATED PRODUCT USING NEGATIVE PHOTORESIST COMPOSITION AND PHOTOSENSITIVE COMPOSITION USED THEREIN}

The present invention relates to a method for forming a multistage plated article using a negative photoresist composition, and to a photosensitive composition used in the above method, and more particularly, to a plating process using a plated article or a thick film multilayer resist pattern having a high aspect ratio. It is related with the shaping | molding method of the multistage plated article which has a complicated shape by implementation, and the photosensitive composition used for the said method.

Claims priority to Japanese Patent Application No. 2004-195034, filed in Japan on June 30, 2004, which is incorporated herein by reference.

In recent years, among the microscopic structure and the micro component molding method represented by MEMS (Micro ElectroMechanical Systems), a molding method using a combination of a thick film lithography method and a plating method has attracted much attention.

However, conventional methods have proved to be difficult to form thick films, and the production of various high-precision tertiary shapes in shapes throughout the thickness direction, such as the formation of gears of different diameters, has proved particularly difficult.

Examples of such a molding method include a complex exposure operation using a different mask pattern and a different exposure amount disclosed in Patent Document 1 and including an overlapping exposure area on a photoresist layer, and then developing the photoresist layer to develop the photoresist. Photoresist processing methods are included that form stepped recesses in the layer.

Furthermore, Patent Document 2 discloses a method of forming a first layer of positive photoresist on a substrate, which is sufficient to partially decompose the active agent in the positive photoresist, but with insufficient amount of photochemically active radiation to dissolve in the developer. Exposing a first layer, applying a second layer of positive photoresist on the first layer, and a sufficient amount of photochemically active radiation to dissolve both the first and second positive photoresist in the developer, Pattern exposure of the layer and the second layer, and developing the first layer and the second layer for forming the opening through the first layer and the second layer. do.

[Patent Document 1]

Japanese Laid-Open Patent Publication No. 2003-29415

[Patent Document 2]

Japanese Laid-Open Patent Publication No. 1 Hei 9-199663

However, in the method of Patent Document 1, since the resist layer is a single layer, and steps are formed by varying the exposure amount in such a layer, in order to accurately reproduce the shape of the short form, high precision of exposure throughout the film thickness direction of the resist One control is required. In addition, when a thick film was used, exposure to the lower layer was insufficient.

In Patent Document 2, since the exposure amount must be set at a level insufficient to dissolve in the developer, similarly to Patent Document 1, high-precision control of the exposure amount is required throughout the film thickness direction of the resist. Furthermore, similarly to Patent Document 1, when a thick film is used, exposure to the underlying layer tended to be unsatisfactory. Moreover, the method of Patent Document 2 discloses only a two-layer resist pattern.

In other methods of multilayer resist pattern formation in which each layer is exposed and developed and then another resist pattern is formed thereon and subsequently exposed and developed, it has proved difficult to obtain satisfactory film flatness and resolution. In addition, the formation of complex shapes has proved impossible in the method of forming a multilayer resist pattern, which is subsequently heated as necessary after application of the resist composition and an additional resist composition is applied thereon.

In view of the conventional circumstances described above, the present invention does not require precise exposure control throughout the film thickness direction, and includes a thick high-precision plated article using a thick film multilayer resist pattern including two or more layers and suitably exposed to the lower layer. It is an object of the present invention to provide a molding method and a method for enabling the formation of complex short shapes in a plated product.

As a result of intensive research aimed at achieving this goal, the inventors of the present invention have found that the above-mentioned problems can be solved by using a specific step using a specific negative photoresist composition and they can thus complete the present invention. .

The present invention is based on the above findings, and the method for forming a plated article according to the present invention comprises the steps of (A) forming a layer of a negative photoresist composition, subsequently exposing the composition after heating and then heating or not heating, ( B) repeating step (A) so that the step (A) is carried out a total of two or more times, stacking the negative photoresist layer and then developing all of the layers simultaneously to form a multilayer resist pattern, and (C Plating) in the multilayer resist pattern, wherein the negative photoresist composition comprises (a) an alkali soluble resin, (b) an acid generator, and (c) other components.

The exposure used in step (A) can preferably form a pattern in all resist layers. Moreover, the exposure surface area of the exposure carried out in step (A) may be larger for the layer further away from the exposure source than for the layer close to the exposure source. The heating after forming the resist layer in step (A) may use an in-heating heat treatment.

The negative photoresist composition according to the present invention comprises (a) an alkali soluble resin, (b) an acid generator and (c) other components. In the composition of the present invention, novolak resin can be used as component (a).

Step (A) may also utilize a step of forming a negative photoresist layer using a negative photoresist composition such as a sheet, and then exposing the layer and heating as necessary.

According to the method for forming a plated article using the negative photoresist composition according to the present invention and the photosensitive composition used in such a method, two or more layers are suitably exposed to the lower layer without requiring precise exposure control throughout the film thickness direction. By using a thick film multilayer resist pattern, a thick high precision plated article can be produced. Moreover, complex short shapes may also be formed in the plated article.

[Brief Description of Drawings]

1 is a perspective image of a substrate and a multilayer resist pattern formed using the multilayer resist pattern forming step utilized in the method of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described as follows.

The plating article forming method of the present invention includes the steps described below. That is, (A) forming a layer of a negative photoresist composition and then heating and exposing the composition (hereinafter referred to as step (A)), (B) such that step (A) is performed a total of two or more times Repeating (A) to stack the negative photoresist layer, and then developing all the layers simultaneously to form a multilayer resist pattern (hereinafter referred to as step (B)) and (C) plating treatment in the multilayer resist pattern Performing (hereinafter referred to as step (C)).

The negative photoresist composition of this invention contains (a) alkali-soluble resin, (b) acid generator, and (c) other component. Suitable examples of negative photoresist compositions used in the present invention include the thick film chemically amplified negative photoresist composition types disclosed in Japanese Patent Laid-Open No. 2003-114531. Each component of the negative photoresist composition of this invention is demonstrated as follows.

(a) alkali-soluble resin

With any alkali soluble resins typically used as base resins in conventional negative chemically amplified photoresists, there are no specific limitations to alkali soluble resins (hereinafter referred to as component (a)), which are typically used for exposure. It is selected from known resins depending on the light source. Novolak resins, acrylic resins, or resins whose main component is a copolymer containing hydroxystyrene structural units, provide excellent properties such as resist shape and resolution and are therefore widely used.

Novolak resins are particularly preferred as component (a). By using a novolak resin as the main component, good peeling properties and excellent plating resistance can be obtained.

Novolak resin

Novolak resins are obtained, for example, by addition condensation of aromatic compounds with phenolic hydroxyl groups (hereinafter simply referred to as phenols) and aldehydes in the presence of an acid catalyst.

Examples of phenols used include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-butylphenol, m-butylphenol, p-butylphenol, 2,3-Xylenol, 2,4-Xylenol, 2,5-Xylenol, 2,6-Xylenol, 3,4-Xylenol, 3,5-Xylenol, 2, 3,5-trimethylphenol, 3,4,5-trimethylphenol, p-phenylphenol, resorcinol, hydroquinone, hydroquinone monomethyl ether, pyrogallol, phloroglucinol, hydroxydiphenyl, bisphenol A, gallic acid, Gallic acid esters, α-naphthol and β-naphthol.

Examples of aldehydes also include formaldehyde, furfural, benzaldehyde, nitrobenzaldehyde and acetaldehyde.

There is no particular limitation on the catalyst used in the addition condensation reaction, but suitable acid catalysts include hydrochloric acid, nitric acid, sulfuric acid, formic acid, oxalic acid and acetic acid.

Of these novolak resins, novolak resins formed from cresol, xylenol and trimethylphenol are particularly preferred. m-cresol novolac resins prepared by condensation of m-cresol and aldehydes are particularly preferred as a result, as they show a particularly good development profile.

The weight average molecular weight of the novolak resin is typically 3,000 to 50,000, preferably 5,000 to 30,000. When the weight average molecular weight is less than 3,000, the thickness of the cured portion of the film tends to decrease (thinner) during development, but when the weight average molecular weight exceeds 50,000, an undesirable residue is developed after development. There is a tendency to remain.

Acrylic resin

The acrylic resin used in the present invention includes (a1) structural units derived from a polymerizable compound having an ether bond and (a2) structural units derived from a polymerizable compound containing a carboxyl group.

(a1) Examples of polymerizable compounds containing ether bonds include (meth) acrylic acid derivatives including both ether bonds and ester bonds, such as 2-methoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) Acrylate, 3-methoxybutyl (meth) acrylate, ethylcarbitol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate and tetrahydrofurfuryl (meth ) Acrylates, of which 2-methoxyethyl (meth) acrylate and methoxytriethylene glycol (meth) acrylate are preferred. These compounds may be used alone or in combination of two or more different compounds.

(a2) Examples of polymerizable compounds containing carboxyl groups contain monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid, dicarboxylic acids such as maleic acid, fumaric acid and itaconic acid, and both carboxyl groups and ester linkages. One compound such as 2-methacryloyloxyethylsuccinic acid, 2-methacryloyloxyethylmaleic acid, 2-methacryloyloxyethylphthalic acid and 2-methacryloyloxyethylhexahydrophthalic acid are included. Among these, acrylic acid and methacrylic acid are preferable. These compounds may be used alone or in combination of two or more different compounds.

The amount in the acrylic resin of the structural unit (a1) derived from the polymerizable compound including the ether bond is preferably 30 to 90% by weight, even more preferably 40 to 80% by weight. If the amount exceeds 90% by weight, the co-solubility of the resin in the resin solvent tends to deteriorate, and it becomes more difficult to obtain a uniform resist film during prebaking, If the amount is less than 30% by weight, cracking tends to occur during plating.

In addition, the amount in the acrylic resin of the structural unit (a2) derived from the polymerizable compound containing a carboxyl group is preferably 2 to 50% by weight, even more preferably 5 to 40% by weight. If the amount is less than 2% by weight, the alkali solubility of the acrylic resin is lowered, which means that satisfactory developability cannot be obtained. Moreover, the peeling properties are also lowered such that residual resist remains on the substrate. When the amount exceeds 50% by weight, the residual film ratio after development tends to decrease and the plating resistance decreases.

Polymers containing hydroxystyrene structural units

Examples of polymers containing hydroxystyrene structural units include hydroxy comprising alpha-alkylhydroxystyrenes such as α-methylhydroxystyrene and α-ethylhydroxystyrene or hydroxystyrenes such as p-hydroxystyrene. Radicals or ionic copolymers formed from styrene structural units alone, and copolymers formed from hydroxystyrene structural units and other different structural units. The proportion of hydroxystyrene structural units in the polymer or copolymer is preferably at least 1% by weight, even more preferably 10 to 30% by weight. The reason for this requirement is that developability and resolution tend to be lowered when the proportion of hydroxystyrene structural units is less than 10% by weight.

The weight average molecular weight of the copolymer containing the hydroxystyrene structural unit is preferably 5,000 or less, even more preferably 2,000 to 4,000. This is because the resolution tends to be lowered when the weight average molecular weight is more than 5,000.

Examples of preferred monomers for forming a structural unit other than the hydroxystyrene structural unit include monomers in which the hydroxyl group of the hydroxystyrene structural unit is substituted with another group and a monomer containing an α, β-unsaturated double bond.

As said other group used for substituting the hydroxyl group of a hydroxystyrene structural unit, the alkali dissolution inhibiting group which does not dissociate under the action of an acid is used. Examples of the alkali dissolution inhibiting group which are not dissociated under the action of an acid include substituted or unsubstituted benzenesulfonyloxy groups, substituted or unsubstituted naphthalenesulfonyloxy groups, substituted or unsubstituted benzenecarbonyloxy groups and substituted or unsubstituted naphthalenecarbonyls Oxy groups are included. Specific examples of the preferred substituted or unsubstituted benzenesulfonyloxy group include benzenesulfonyloxy group, chlorobenzenesulfonyloxy group, methylbenzenesulfonyloxy group, ethylbenzenesulfonyloxy group, propylbenzenesulfonyloxy group, methoxybenzenesulfonyloxy group, Oxybenzenesulfonyloxy group, propoxybenzenesulfonyloxy group and acetoaminobenzenesulfonyloxy group, while specific examples of the preferred substituted or unsubstituted naphthalenesulfonyloxy group include naphthalenesulfonyloxy group, chloronaphthalenesulfonyloxy group, Methylnaphthalenesulfonyloxy group, ethylnaphthalenesulfonyloxy group, propylnaphthalenesulfonyloxy group, methoxynaphthalenesulfonyloxy group, ethoxynaphthalenesulfonyloxy group, propoxynaphthalenesulfonyloxy group, and acetoaminonaphthalenesulfonyloxy group are contained. Examples of the substituted or unsubstituted benzenecarbonyloxy group and the substituted or unsubstituted naphthalenecarbonyloxy group include the substituted or unsubstituted sulfonyloxy group, wherein the sulfonyloxy group is substituted with a carbonyloxy group. Among these groups, acetoaminobenzenesulfonyloxy group and acetoaminonaphthalenesulfonyloxy group are particularly preferable.

In addition, specific examples of the monomer containing an α, β-unsaturated double bond include styrene-based monomers such as styrene, chlorostyrene, chloromethylstyrene, vinyltoluene and α-methylstyrene, acrylate monomers such as methyl acrylate, methyl meta Monomers such as acrylate and phenyl methacrylate, and vinyl acetate and vinyl benzoate, among which monomers, styrene is preferred.

Among various copolymers comprising hydroxystyrene structural units, such copolymers formed from hydroxystyrene and styrene, such as poly (4-hydroxystyrene-styrene) copolymers and poly (4-hydroxystyrene-methylstyrene) The coalescence shows high resolution and excellent heat resistance and is consequently desirable.

The resin or copolymer of component (a) can be used alone or in admixture of two or more different materials.

When component (a) is a mixed resin containing novolak resin and / or an acrylic resin, and a copolymer containing hydroxystyrene structural unit, when the compounding weight of the two components is 100 parts by weight, the novolak resin and / Or the amount of acrylic resin is typically 50 to 98 parts by weight, preferably 55 to 95 parts by weight, and the amount of the copolymer including hydroxystyrene structural units is 50 to 2 parts by weight, preferably 45 to 5 parts by weight. to be. This type of blending ratio is used to improve both developability and resolution, and as a result this is desirable.

The aforementioned component (a) typically accounts for 30 to 99 parts by weight, preferably 65 to 95 parts by weight, for each 100 parts by weight of the combined solids of the components (a) to (c).

If the amount of component (a) is less than 50 parts by weight, the plating resistance, plating shape and peeling properties may be undesirably reduced. On the other hand, if the amount exceeds 99 parts by weight, undesirable development defects may occur. May occur during the phenomenon.

(b) acid generators

There is no particular limitation on the acid generator used in the present invention (hereinafter referred to as component (b)) as long as it generates acid directly or indirectly upon irradiation with light. Specific examples of suitable acid generators include: halogen-containing triazine compounds, such as 2,4-bis (trichloromethyl) -6- [2- (2-furyl) ethenyl] -s-triazine , 2,4-bis (trichloromethyl) -6- [2- (5-methyl-2-furyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2 -(5-ethyl-2-furyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (5-propyl-2-furyl) ethenyl] -s- Triazine, 2,4-bis (trichloromethyl) -6- [2- (3,5-dimethoxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (3,5-diethoxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (3,5-dipropoxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (3-methoxy-5-ethoxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloro Rhomethyl) -6- [2- (3-methoxy-5-propoxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (3,4 Methylenedioxyphenyl) Tenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- (3,4-methylenedioxyphenyl) -s-triazine, 2,4-bis-trichloromethyl-6- ( 3-bromo-4-methoxy) phenyl-s-triazine, 2,4-bis-trichloromethyl-6- (2-bromo-4-methoxy) phenyl-s-triazine, 2,4 -Bis-trichloromethyl-6- (2-bromo-4-methoxy) styrylphenyl-s-triazine, 2,4-bis-trichloromethyl-6- (3-bromo-4-meth Methoxy) styrylphenyl-s-triazine, 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxynaphthyl ) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (2-furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3 , 5-triazine, 2- [2- (5-methyl-2-furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- ( 3,5-dimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,4-dimethoxyphenyl) ethenyl]- 4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (3,4-methylenedioxype ) -4,6-bis (trichloromethyl) -1,3,5-triazine, 1,3,5-triazine-tris (1,3-dibromopropyl); And tris (2,3-dibromopropyl) -1,3,5-triazine and halogen-containing isocyanurate compounds represented by the following formulae, such as tris (2,3-dibromopropyl) isocyanurate :

[Wherein, R ¹ to R ³ may be the same or different and each represents a halogenated alkyl group].

Other specific examples of component (b) include: α- (p-toluenesulfonyloxyimino) -phenylacetonitrile, α- (benzenesulfonyloxyimino) -2,4-dichlorophenylacetonitrile, α -(Benzenesulfonyloxyimino) -2,6-dichlorophenylacetonitrile, α- (2-chlorobenzenesulfonyloxyimino) -4-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -1 Cyclopentenylacetonitrile, and a compound represented by the formula:

[Wherein, R ⁴ represents a monovalent to trivalent organic group, R ⁵ represents a substituted or unsubstituted saturated hydrocarbon group, an unsaturated hydrocarbon group or an aromatic compound group, and n represents a natural number of 1 to 3]. As used herein, the term "aromatic compound group" refers to a group formed from a compound that exhibits the characteristic physical and chemical properties of an aromatic compound, and specific examples include aromatic hydrocarbon groups such as phenyl or naphthyl groups, and heterocyclic groups such as furyl groups or Thienyl groups are included. These groups may also include suitable substituents including one or more halogen atoms, alkyl groups, alkoxy groups or nitro groups on the ring. Moreover, as an R <^5> group, the C1-C4 alkyl group containing a methyl group, an ethyl group, a propyl group, and a butyl group is especially preferable. Particularly preferred are compounds in which R ⁴ represents an aromatic compound group and R ⁵ represents a lower alkyl group. Examples of the acid generated shown by the above formula, n = 1 in the case where R ⁴ is a phenyl group, methylphenyl group or methoxyphenyl group and R ⁵ is a methyl group in the compound, that is, α- (methylsulfonyl oksiyi mino) -1-phenyl Acetonitrile, α- (methylsulfonyloxyimino) -1- (p-methylphenyl) acetonitrile and α- (methylsulfonyloxyimino) -1- (p-methoxyphenyl) acetonitrile. When n = 2, specific examples of the acid generator represented by the above formula include an acid generator represented by the following formula:

Further specific examples of component (b) include bissulfonyldiazomethanes such as bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) ) Diazomethane and bis (2,4-dimethylphenylsulfonyl) diazomethane; Nitrobenzyl derivatives such as 2-nitrobenzyl p-toluenesulfonate, 2,6-nitrobenzyl p-toluenesulfonate, nitrobenzyl tosylate, dinitrobenzyl tosylate, nitrobenzyl sulfonate, nitrobenzyl carbonate and di Nitrobenzyl carbonates, sulfonic acid esters such as pyrogallol trimesylate, pyrogallol tritosylate, benzyl tosylate, benzyl sulfonate, N-methylsulfonyloxysuccinimide, N-trichloromethylsulfonyloxysuccinate Mid, N-phenylsulfonyloxymaleimide and N-methylsulfonyloxyphthalimide; Onium salts such as diphenyliodonium hexafluorophosphate, (4-methoxyphenyl) phenyliodonium trifluoromethanesulfonate, bis (p-tert-butylphenyl) iodonium trifluoromethanesulfonate, triphenyl Sulfonium hexafluorophosphate, (4-methoxyphenyl) diphenylsulfonium trifluoromethanesulfonate and (p-tert-butylphenyl) diphenylsulfonium trifluoromethanesulfonate; Benzoin tosylate such as benzoin tosylate and α-methylbenzoin tosylate; And other diphenylyodonium salts, triphenylsulfonium salts, phenyldiazonium salts and benzyl carbonates. The triazine compound has a particularly high performance as an acid generator under light irradiation and good solubility when a solvent is used, which is preferable as a result. Among the triazine compounds, bromo-containing triazine compounds, in particular 2,4-bis-trichloromethyl-6- (3-bromo-4-methoxy) phenyl-s-triazine, 2,4-bis- Trichloromethyl-6- (3-bromo-4-methoxy) styrylphenyl-s-triazine and tris (2,3-dibromopropyl) isocyanurate are preferably used. The acid generator of component (b) can be used individually or in mixture of 2 or more different compounds.

The amount of component (b) is typically from 0.01 to 5 parts by weight, preferably from 0.05 to 2 parts by weight, even more preferably from 0.1 to 1 part by weight, based on 100 parts by weight of the combined solids of components (a) to (c). It is wealth. If the amount of component (b) is less than 0.01 part by weight, crosslinking curing does not proceed satisfactorily in the presence of heat and light, which tends to lower the plating resistance, chemical resistance and adhesion of the coating film as a product, It means that the shape tends to be lower. In contrast, when the amount exceeds 5 parts by weight, undesirable developing defects may occur during development.

(c) other ingredients

Examples of other components (hereinafter referred to as component (c)) used in the present invention include crosslinking agents. As crosslinking agents, amino compounds such as melamine resins, urea resins, guamine resins, glycoluril formaldehyde resins, succinamideamide-formaldehyde resins or ethylene urea-formaldehyde resins can be used, and alkoxymethylated amino resins such as alkoxy Methylated melamine resins or alkoxymethylated urea resins are particularly preferred. The alkoxymethylated amino resin reacts a boiling aqueous solution of melamine or urea with formalin to produce a condensation product, which is then etherified with a lower alcohol such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol or isopropyl alcohol. The reaction mixture can then be cooled and prepared by precipitation of the product. Specific examples of the alkoxymethylated amino resin include methoxymethylated melamine resin, ethoxymethylated melamine resin, propoxymethylated melamine resin, butoxymethylated melamine resin, methoxymethylated urea resin, ethoxymethylated urea resin, propoxymethylated urea resin And butoxymethylated urea resins. These alkoxymethylated amino resins can be used alone or in combination of two or more different materials. The alkoxy methylated melamine resin is particularly preferable because it can exhibit a minimum change in the resist pattern dimension in accordance with the change in the radiation exposure amount to form a stable resist pattern. Among these resins, methoxymethylated melamine resins, ethoxymethylated melamine resins, propoxymethylated melamine resins and butoxymethylated melamine resins are ideal. The amount of the crosslinking agent used is typically 1 to 30 parts by weight, preferably 5 to 20 parts by weight, relative to 100 parts by weight of the combined solids of the components (a) to (c). When the amount of component (c) is less than 1 part by weight, the plating resistance, chemical resistance and adhesion of the coating film as a product tends to be lowered, and the shape of the plated product tends to be lower. Conversely, undesirable development defects may occur during development if the amount exceeds 30 parts by weight.

In addition, the negative photoresist compositions of the present invention may also incorporate an appropriate amount of organic solvent for viscosity adjustment. Specific examples of suitable solvents include: ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl Ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether Diethylene glycol monophenyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, Ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monobutyl Ether acetate, diethylene glycol monophenyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxy Butyl acetate, 2-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, ethyl isobutyl ketone, tetrahydrofuran, cyclohexanone, Methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate Nate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, ethyl-3-propoxypropionate, propyl-3-methoxypropionate Nate, Isopropyl-3-methoxypropione , Ethyl ethoxyacetate, ethyl oxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isoamyl acetate, methyl carbonate, Ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, benzyl methyl ether, benzyl ethyl ether, dihexyl ether , Benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, benzene, toluene, xylene, cyclohexanone, methanol, ethanol, propanol, butanol, hexanol, cyclohexanol, Ethylene glycol, diethylene glycol and glycerol. These solvents may be used alone or in combination of two or more solvents. In order to enable spin coating of the resulting negative photoresist composition to enable formation of a coating film having a thickness of at least 20 μm, the amount of solvent is preferably sufficient to provide a solids concentration of 65% by weight or less. If the solid content concentration exceeds 65%, the fluidity of the composition is significantly lowered, making handling difficult and difficult to obtain a uniform resist film by spin coating.

If desired, the compositions of the present invention may further comprise quenchers such as triethylamine, tributylamine, dibutylamine, triethanolamine and other secondary or tertiary amines in addition to the components described above.

Surfactants can also be formulated into the compositions of the present invention to enhance properties such as coatings, antifoams and leveling properties. Examples of suitable surfactants include anionic, cationic and nonionic surfactants. Specific examples include BM-1000 and BM-1100 (manufactured by BM Chemie GmbH), Megafac F142D, Megafac F172, Megafac F173 and Megafac F183 (manufactured by Daiippon Ink & Chemicals, Incorporated), Fluorad FC-135, Fluorad FC-170C, Flurad FC-430 and Fluorad FC-431 (manufactured by Sumitomo 3M Limited), Surfron S-112, Surfron S-113, Surfron S-131, Surfron S-141 and Surfron S-145 (manufactured by Asahi Glass Co., Ltd) and SH Fluorine-containing surfactants sold under the trade names -28PA, SH-190, SH-193, SZ-6032 and SF-8428 (manufactured by Toray Silicone Co., Ltd.). The amount of such surfactant used is preferably 5 parts by weight or less per 100 parts by weight of the alkali-soluble resin (a).

The composition of the present invention may also use adhesion aids for improving adhesion with the substrate. As the adhesion aid, a functional silane coupling agent is particularly effective. As used herein, the term "functional silane coupling agent" refers to a silane coupling agent each having a reactive substituent such as a carboxyl group, methacryloyl group, isocyanate group or epoxy group. Specific examples include trimethoxysilylbenzoic acid, γ-methacryloyloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane and β- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane. As for the compounding quantity of an adhesion | attachment adjuvant, 20 weight part or less is preferable per 100 weight part of alkali-soluble resin (a).

In order to finely control the solubility in the alkaline developer, the compositions of the present invention may also include: added monocarboxylic acids such as acetic acid, propionic acid, n-butyric acid, iso-butyric acid, n-valleic acid, Iso-valeric acid, benzoic acid and cinnamic acid; Hydroxy monocarboxylic acid, yes to lactic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, salicylic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 2-hydroxycinnamic acid, 3-hydroxycinnamic acid , 4-hydroxycinnamic acid, 5-hydroxyisophthalic acid and syringic acid; polycarboxylic acids such as oxalic acid, succinic acid, glutaric acid, adipic acid, maleic acid, itaconic acid, hexahydrophthalic acid, Phthalic acid, isophthalic acid, terephthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, trimellitic acid, pyromellitic acid, cyclopentanetetracarboxylic acid, butanetetracarboxylic Acids and 1,2,5,8-naphthalenetetracarboxylic acid; Or acid anhydrides such as itaconic anhydride, succinic anhydride, citraconic anhydride, dodecenyl succinic anhydride, tricarbanylic anhydride, maleic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, force anhydride, 1,2, 3,4-butanetetracarboxylic anhydride, cyclopentanetetracarboxylic dianhydride, phthalic anhydride, pyromellitic anhydride, trimellitic anhydride, benzophenonetetracarboxylic anhydride, ethylene glycol arsenic hydrotrimellitate and glycerol Triacid hydrotrimellitate. In addition, the composition may also include: added high boiling solvents such as N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethyl Acetamide, N-methylpyrrolidone, dimethylsulfoxide, benzyl ethyl ether, dihexyl ether, acetonyl acetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl Acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate and phenyl cellosolve acetate. The amount of the compound added to finely control the solubility of the composition in the alkaline developer may be set according to such factors as the intended use and the coating method utilized, but there is no particular limitation on the amount provided, but the mixture is mixed To produce a uniform composition, typically the amount is up to 60% by weight, preferably up to 40% by weight of the resulting composition.

In addition, other additives such as fillers, colorants and viscosity modifiers may also be added to the compositions of the present invention as needed. Examples of suitable fillers include silica, alumina, talc, bentonite, zirconium silicate and powder glass. Examples of suitable colorants include extender pigments such as alumina white, clay, barium carbonate and barium sulphate; Inorganic pigments such as zinc white, white lead, chrome yellow, red lead, ultramarine blue, iron blue, titanium oxide, zinc chromate, red iron oxide and carbon black; Organic pigments such as vivid carmine 6B, permanent red 6B, permanent red R, benzidine yellow, phthalocyanine blue and phthalocyanine green; Basic dyes such as magenta and rhodamine; Direct dyes such as direct crimson and direct orange; And acid dyes such as roserin and methyl yellow. Examples of suitable viscosity modifiers also include bentonite, silica gel and aluminum powder. These additives may be added in amounts that do not impair the essential properties of the composition, preferably up to 50% by weight of the resulting composition.

Moreover, antifoams and other additives may also be added to the compositions of the present invention as needed. Examples of the antifoaming agent include silicone-based and fluorine-based antifoaming agents. Other components of component (c) may be used alone or in combination of two or more different materials.

The amount of component (c) is typically at least 1 part by weight, preferably at least 5 parts by weight, typically at most 50 parts by weight, preferably per 100 parts by weight of the combined solids of components (a) to (c) Is 30 parts by weight or less. If the amount of component (c) is less than 1 part by weight, the resulting coated film may not exhibit satisfactory performance.

If no fillers or pigments are added to the composition of the present invention, the composition of the present invention may be prepared by simply mixing and stirring the components together using conventional methods. If a filler or pigment added to the composition is contained, the components can be dispersed and mixed using a dispersing device such as a dissolver, homogenizer or three-roll mill. In addition, the composition may also be filtered using a net or membrane filter, if desired.

The composition of this invention is used for the shaping | molding method of the plating goods mentioned below. When the composition of the present invention is used to form a negative photoresist film, the film thickness of a single layer is typically 10 to 2000 μm, preferably 20 to 1000 μm, even more preferably 50 to 500 μm.

Negative photoresist compositions such as sheets

A negative photoresist composition, such as a sheet according to the invention, is prepared by applying the negative photoresist composition of the invention to the surface of a releasable support film and drying the applied coating to form a negative photoresist film. A negative photoresist composition, such as the sheet of the present invention, can be used in step (A) described above to form a layer of negative photoresist composition. Negative photoresist compositions, such as the sheet of the present invention, are protected and easily stored, transported and handled by a releasable film that can be easily removed from the negative photoresist film surface and exhibit a high level of film flatness and a coating on the substrate. Facilitate film formation.

There is no specific limitation to the support film used in the preparation of the negative photoresist composition, such as the sheet of the present invention, any of which allows for easy removal of the coated layer onto the support film, and any transfer of such layer to the glass substrate. Releasable films can be used. Suitable examples include thermoplastic resin flexible films formed from synthetic resin films having a film thickness of 15 to 125 μm comprising polyethylene terephthalate, polyethylene, polypropylene, polycarbonate and polyvinyl chloride. If desired, the support film can be applied to a release treatment to further facilitate film movement.

In order to form the negative photoresist film on the support film, the negative photoresist composition of the present invention is prepared and then coated with an applicator, bar coater, wire bar coater, roll coater or curtain flow coater or the like. Is applied to the surface of the support film. Roll coaters are preferred as a result because they can evenly achieve a good film thickness and form thick films efficiently.

After drying the applied coating, it is preferable that the protective film is adhered to the surface of the negative photoresist film in order to stably protect the negative photoresist film before use. Suitable examples of such protective films include polyethylene terephthalate films, polypropylene films or polyethylene films having a thickness of 15 to 25 μm and comprising a layer of coated or baked silicone.

The plating article molding method of the present invention is carried out in the manner described below.

(A) forming a layer of negative photoresist composition, heating and exposing the composition and further heating as necessary.

A solution of the negative photoresist composition prepared in the manner described above is applied to the surface of the substrate or resist layer with the above thickness and then heated to remove the solvent and form the desired negative resist layer (negative photoresist film). As the substrate, a conventional substrate can be used. Suitable examples of such substrates include substrates of silicon, gold, copper, nickel and palladium, and substrates on which layers of one of these metals are formed on substrates of different materials. As a method of applying the composition to the substrate or the resist layer, a spin coating, slit coating, screen printing or applicator method may be utilized.

Heating conditions utilized in the applied coatings of the compositions of the present invention vary depending on factors such as the nature of the components in the composition, the blending ratio and coating thickness, etc., but typically between 70 and 140 ° C., preferably between 80 and 120 ° C. , 2 to 60 minutes. As the heating method, a hot plate method or an oven-based method may be used, but the oven method is preferable because it allows heating from both the upper and lower sides, thereby making it possible to apply heat more effectively.

In addition, when a negative photoresist composition such as the sheet described above is used, the protective film is first removed from the negative photoresist such as the sheet, and the exposed negative photoresist film is overlaid on the substrate or the resist layer and then using a known method. It is joined or pressure bonded from the supporting film side. For example, movement of the heating roller can be used to thermocompress bond the negative photoresist film to the substrate surface. Subsequently, the support film is removed, thereby exposing the negative photoresist film surface to complete the formation of the negative photoresist layer. If the support film is transparent relative to the exposure light, the exposure treatment can be carried out before removing the support film. Thermocompression bonding typically involves heating the substrate surface to a temperature of 80-140 ° C. and then using a roll pressure of 1-5 kg / cm 2 and a moving speed of 0.1-10.0 m / min. The substrate may also be preheated if desired, and the preheat temperature is typically selected in the range of 40 to 100 ° C.

The coating film is then irradiated with ultraviolet or visible light with a wavelength of 300 to 500 nm and irradiated through the entire film surface or a mask having a predetermined pattern, so that only the pattern portion required for forming the entire surface of the film or a plated article is obtained. Exposed. As the light source for irradiation, a low pressure mercury lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp, a metal halide lamp or an argon gas laser or the like can be used. In the present description, the term “irradiation” refers to ultraviolet rays, visible rays, far ultraviolet rays, X-rays, electron beams, and the like. The exposure dose varies depending on the nature of each component in the composition, the blending ratio used and the thickness of the coating film, but typical exposure doses when an ultrahigh pressure mercury lamp is used range from 100 to 3,000 mJ / cm 2.

In addition, after exposure, further heating (post-exposure bake) may be carried out using one of the above-described methods as necessary. Oven-based heating is preferred because it allows heating both above and below to allow more effective application of heating to the resist layer.

(B) repeating step (A) and performing the above steps two or more times in total, stacking them on a negative photoresist layer and developing all the layers simultaneously to form a multilayer resist pattern.

Step (A) is carried out to stack the negative photoresist layer two or more times. By heating the negative photoresist composition after layer formation, the exposed surface of the resist layer becomes hard so that an additional resist layer can be superimposed thereon without deforming the underlying layer. The resulting multilayer resist has at least two layers, preferably 2 to 20 layers, even more preferably 2 to 10 layers. The combined film thickness of the overlaid resist layer is typically at least 20 μm, preferably in the range from 40 to 1,000 μm.

In the present invention, it is preferable that the exposure performed in the above-mentioned step (A) is a pattern forming exposure process performed through all the resist layers. This allows for the preparation of multilayer negative resist compositions that do not include the entire exposure layer.

Particularly preferred is a structure in which the surface area exposed during the exposure carried out in step (A) is larger in the exposure area of the layer located away from the exposure light source than the exposure area of the layer located close to the light source. This improves the pattern shape stability of the multilayer resist pattern, thus facilitating subsequent plating.

In addition, a structure in which the pattern shape is different for each resist pattern layer is also possible. This means that a three-dimensional shape whose shape is variable throughout the film thickness direction, such as gears of different diameters, can be molded as a plated product.

All resist layers of the nested multilayer negative resist composition thus obtained are developed simultaneously using conventional methods. The development method after such irradiation includes using an aqueous alkali solution as a developer and dissolving and removing unnecessary unirradiated portions. Suitable examples of the developer include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia water, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, Dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5,4,0] -7-undecene and 1,5 Aqueous solutions of alkali metals such as -diazabicyclo [4,3,0] -5-nonane. Aqueous solutions prepared by adding a suitable amount of a water-soluble organic solvent such as methanol or ethanol, or a surfactant to an aqueous solution of any of the above alkali compounds can also be used as developer.

The development time varies depending on the nature of each component in the composition, the blending ratio used and the dried film thickness of the composition, but typically ranges from 1 to 30 minutes. Suitable development methods also include spin methods, dipping methods, puddle methods, and spray development methods. After development, the structure is washed for 30 to 90 seconds under running water and then dried using an air gun or oven or the like.

(C) Plating step in multilayer resist pattern

There is no particular limitation on the plating method, but any conventional plating method may be used. For example, as a method of plating in a portion removed from the resist, an electroplating method or an electroless plating method may be selected as necessary. In addition, as the plating metal, gold, copper, solder, nickel or the like can be selected as necessary. This plating treatment causes the plated article to be molded.

After forming the plated article, the multilayer resist pattern can be removed using a conventional removal method. Suitable removal methods include resist incineration and cleaning methods, and methods in which the resist pattern is in contact with (immersed in) a conventional stripping solution composition. The method using a peeling solution composition is preferable from a viewpoint of ease of use and limiting damage of a plated product. Moreover, the multilayer resist pattern of the present invention exhibits good peeling characteristics with respect to the peeling solution. Specific examples of removal methods utilized when using a peel resist composition on a multilayer resist pattern include dipping, immersion, and shower methods. Ultrasonic agitation can also be used during exfoliation. Once the resist pattern is removed from the substrate, the substrate is cleaned using conventional methods and then dried.

This step enables the molding of multi-step shaped plated articles having a height on the substrate of 20 μm or more. The method can be used even in the formation of multi-stage plated articles or variable diameter plated articles having a depth of 100 μm or more, which could not be achieved by conventional methods, which is very useful for the production of microelectronic devices or microcomponents represented by MEMS.

Examples of the present invention are described below, but these are presented to facilitate the description of the present invention and are not intended to be limiting. Unless otherwise specified, "parts" refers to parts by weight in% by weight.

Synthesis Example 1

Formalin was added to m-cresol, followed by condensation under conventional conditions using oxalic acid as a catalyst to give a meta-cresol novolak resin. The resin was subjected to fractionation to remove the low molecular weight portion to give a novolak resin having a weight average molecular weight of 6,000.

Synthesis Example 2

35 parts by weight of dicyclopentanyl methacrylate, 10 parts by weight of methacrylic acid, 25 parts by weight of 2-hydroxyethyl methacrylate, 25 parts by weight of styrene and 5 parts by weight of 1,3-butadiene were subjected to radical polymerization using conventional methods. Application to obtain an acrylic resin. The resin was subjected to a fractionation method to obtain an acrylic resin having a weight average molecular weight of 20,000.

(Example 1)

The various components (units by weight) listed in the table below were mixed together to obtain a chemically amplified negative photoresist composition. A gold substrate was used as a substrate for applying a resist.

Step (A): The negative photoresist composition was applied to the substrate upper surface in a sufficient amount to produce a dried film thickness of 100 μm and the applied coating was heated in a 120 ° C. oven for 10 minutes. Subsequently, an exposure apparatus (trade name: Cannon PLA501F Hardcontact, manufactured by Cannon Inc.) was used to expose the resist film in a test pattern using an exposure of 2000 mJ / cm 2 and the exposed resist was subsequently subjected to further heat treatment (after exposure). Baking) was applied in an oven at 120 ° C. for 10 minutes.

Step (B): Repeat step (A) to stack on another resist layer and then the structure for 15 minutes with a developer (trade name: P-7G of PMER series developer, manufactured by Tokyo Ohka Kogyo Co., Ltd.). It was developed to form a multilayer resist pattern. The shape of the multilayer resist pattern thus obtained was confirmed under a scanning electron microscope (SEM).

Step (C): Subsequently, 340 g nickel sulfamate, 40 g nickel chloride, 40 g boric acid and 22 ml additive (trade name: Lectronic 10-03S, manufactured by Japan Electroplating Engineers Co., Ltd.) Ni electroplating was performed using the 1-liter plating solution included on the conditions containing the current density of 2 A / dm <^2> , 50 degreeC, and the plating time of 9 hours. Then, the plated product was molded by peeling with a peeling solution (Stripper 710, manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 80 ° C. for 1 hour. The shape of the plated article thus formed and the presence of any resist stripping residue were confirmed under SEM (scanning electron microscope).

(Example 2)

Repeat step (A) twice in step (B) (3 times in total), except that the treatment time is changed to 50 minutes for development, 15 hours for plating, and 1 hour and 30 minutes for peeling. Then, the plated product was molded in the same manner as in Example 1.

(Example 3)

In step (B), step (A) is repeated three times (total four times in total), except that the treatment time is changed to 90 minutes for development, 18 hours for plating, and 2 hours for peeling. The plated article was molded in the same manner as in Example 1.

(Example 4)

In step (A), the resist composition is applied in an amount sufficient to provide a dried film thickness of 50 μm, the applied coating is heat treated at 120 ° C. for 10 minutes and in a pattern using an exposure of 1000 mJ / cm 2. Except for exposing the resist film and applying the resist to further heat treatment (post exposure bake) at 120 ° C. for 10 minutes and then developing for 10 minutes, plating for 4 hours 30 minutes and peeling for 30 minutes The plated article was molded in the same manner as in Example 1.

(Example 5)

In step (A), the resist composition is applied in an amount sufficient to provide a dried film thickness of 150 μm, the applied coating is heat treated at 120 ° C. for 10 minutes, and the pattern is exposed using an exposure of 3000 mJ / cm 2. Except for exposing the resist film and applying the resist to further heat treatment (post exposure bake) at 120 ° C. for 10 minutes and then developing for 50 minutes, plating for 15 hours and peeling for 1 hour 30 minutes The plated article was molded in the same manner as in Example 1.

(Comparative Example 1)

100 parts by weight of alkali-insoluble epoxy resin (trade name: Epikote 157S70, manufactured by Japan Epoxy Resins Co., Ltd.), 3 parts by weight of acid generator (trade name: Adeka Optomer SP-170, manufactured by Asahi Denka Co., Ltd.), and 50 The plated article was molded in the same manner as in Example 1 except that parts by weight of γ-butyrolactone were mixed as a solvent and a chemically amplified negative photoresist composition prepared using propylene glycol monomethyl ether acetate as a developer. . After molding the plated product, peeling was attempted in a manner similar to the above, but the resin could not be peeled off.

In this example, using an alkali insoluble resin means that excellent results cannot be obtained.

(Comparative Example 2)

Using the same chemically amplified negative photoresist composition as used in Example 1, a gold substrate was used as the substrate to which the resist was applied.

Step (A): The negative photoresist composition was applied to the top surface of the substrate in an amount sufficient to produce a dried film thickness of 100 μm, and the applied coating was heated in a 120 ° C. oven for 10 minutes. Subsequently, the resist film was exposed to a test pattern using an exposure apparatus (trade name: Canon PLA501F Hardcontact, manufactured by Canon Inc.) at 2000 mJ / cm 2, and then the exposed resist was further heated in a 120 ° C. oven for 10 minutes. (Post exposure bake). The resist was then developed for 10 minutes with a developer (trade name: P-7G of a PMER series developer, manufactured by Tokyo Ohka Kogyo Co. Ltd) to form a resist pattern.

Step (B): Step (A) was repeated to overlap another resist film to form a multilayer resist pattern. The shape of the multilayer resist pattern thus obtained was confirmed under a scanning electron microscope (SEM).

Step (C): The plated product was molded in the same manner as in Example 1. The shape of the plated article thus formed and the presence of any resist stripping residue were confirmed under SEM (scanning electron microscope). The multilayer resist pattern thus formed exhibited inferior film flatness and unsatisfactory resolution, and could not form satisfactory plated products.

In this embodiment, the layers are not developed all at the same time but develop one layer at a time, so excellent results were not obtained.

(Comparative Example 3)

4 parts by weight of 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer as photopolymerization initiator, 8 parts by weight of 2,2-dimethoxy-1,2-diphenylethan-1-one and synthesis A mixture of 100 parts by weight of the acrylic resin of Example 2 and 30 parts by weight of ethylene oxide-modified trimethylolpropane triacrylate (trade name: Aronix M-350, manufactured by Toagosei Co., Ltd.), polyethylene glycol diacrylate (trade name: NK 10 parts by weight of ester A-200, manufactured by Shin-Nakamura Chemical Co., Ltd, 10 parts by weight of N-vinylpyrrolidone (trade name: Aronix M-150, manufactured by Toagosei Co., Ltd), 0.1 parts by weight of methylhydroquinone, The plated article was prepared in the same manner as in Example 1 except for using a photopolymerizable negative photoresist composition comprising 50 parts by weight of propylene glycol monomethyl ether acetate (PGMEA) and 50 parts by weight of methyl isobutyl ketone as the negative photoresist composition. Molded into. The resolution of the resulting multilayer resist pattern was unsatisfactory and the shape of the molded plated article was also inferior.

In this example, since a photopolymerizable negative photoresist composition was used, no favorable results could be obtained.

(Unless otherwise stated, numbers refer to parts by weight) Ingredient ^{* 1} Example Comparative example One 2 3 4 5 1 ^{* 2} 2 3 ^{* 3} Suzy (a-1) 90 90 90 90 90 - 90 - Acid generator (b-1) 0.5 0.5 0.5 0.5 0.5 - 0.5 - Crosslinker (c-1) 10 10 10 10 10 - 10 - Other ingredients (d-1) 150 150 150 150 150 - 150 - (d-2) 10 10 10 10 10 - 10 - Film thickness of each resist layer 100 100 100 50 150 100 100 100 Number of levels nested in multilayer resist 2 3 4 2 2 2 2 2 Film flatness after the second layer A A A A A A C A resolution A A A A A A C B Plating geometry A A A A A A - C Peeling properties A A A A A C A A

(c-1):가교결합제: 헥사메톡시메틸화 멜라민 (상표명: Nikalac MW-100, Sanwa Chemical Co., Ltd 제조) (d-1): 용매: 프로필렌 글리콜 모노메틸 에테르 아세테이트 (d-2): 단량체: 히드록시스티렌 단량체 (Mw = 2,500) (상표명: VP-2500, Nippon Soda Co., Ltd. 제조) 주석 *2: 비교예 1의 배합 성분을 비교예 1 의 상세한 설명에 기재했다. 주석 *3: 비교예 3 의 배합 성분을 비교예 3 의 상세한 설명에 기재했다. Note * 1: (a-1): Alkali-soluble resin: novolak resin of Synthesis Example 1 (Mw = 6,000) (b-1): Acid generator represented by the following formula [Formula 4]

(c-1): Crosslinking agent: Hexamethoxymethylated melamine (trade name: Nikalac MW-100, manufactured by Sanwa Chemical Co., Ltd.) (d-1): Solvent: Propylene glycol monomethyl ether acetate (d-2): Monomer: Hydroxystyrene monomer (Mw = 2,500) (trade name: VP-2500, manufactured by Nippon Soda Co., Ltd.) Tin * 2: The compounding component of Comparative Example 1 was described in the detailed description of Comparative Example 1. Note * 3: The compounding component of Comparative Example 3 was described in the detailed description of Comparative Example 3.

evaluation

The film flatness, resolution, plating shape and peeling characteristics of the multilayer resist pattern were evaluated using the following criteria. The results are shown in Table 1.

In the resolution evaluation, various types of line and space patterns of different sizes (within a range of 20 to 80 µm and a depth of 20 µm) were formed and evaluated. The film flatness after the second layer is as follows:

A: film thickness error is within ± 10%

B: Film thickness error is greater than ± 10% but within ± 20%.

C: film thickness error exceeds ± 20%.

resolution:

A: After step (B), 40 μm line and space pattern is resolved in all layers

B: After step (B), 60 μm line and space pattern is resolved in all layers

C: One or more layers cannot be resolved.

Plating geometry:

A: The contact angle between the interface of each layer and the plating composition is within 90 ° ± 15 °

C: The contact angle of the interface of each layer and the plating composition is not within 90 ° ± 15 °.

Peeling Characteristics:

A: The resist cannot be peeled off

B: Some exfoliation residue remains

C: No peeling possible.

It is revealed from the above results that the molding method of the plated article of the present invention enables the formation of a multilayer resist pattern having excellent resolution and peeling properties, and the shape of the resulting plated article is also excellent.

As described above, the method for forming a multistage plated article using the negative photoresist composition according to the present invention and the photosensitive composition used therein are very useful for molding a thick film plated article having a multistage shape, and are represented by MEMS. Or it is especially useful for manufacture of the plating goods used for a micro component.

Claims (10)

(A) forming a layer of negative photoresist composition, and then heating and subsequently exposing the layer, and then heating or not heating, (B) the step (A) such that step (A) is performed a total of two or more times Repeatedly stacking the negative photoresist layer and then developing all of the layers simultaneously to form a multilayer resist pattern, and (C) performing a plating process in the multilayer resist pattern. The molding method, wherein the negative photoresist composition comprises (a) an alkali-soluble resin and (b) an acid generator. The plating article molding method according to claim 1, wherein the exposure in step (A) is pattern forming exposure in all the resist layers. The method for forming a plated article according to claim 1, wherein an exposure surface area of the exposure performed in step (A) is larger for a layer farther from an exposure source than for a layer closer to the exposure light source. 2. The method for forming a plated product according to claim 1, wherein the heating after forming the resist layer in the step (A) uses an oven heat treatment. The plating article molding method according to claim 1, wherein the component (a) is a novolak resin. delete delete (A) forming a layer of negative photoresist composition using a sheet-like film made from the negative photoresist composition, exposing the layer and then heating or not heating, (B) step (A) Repeating step (A) so as to perform a total of two or more times in total, stacking the negative photoresist layer and then developing all the layers simultaneously to form a multilayer resist pattern, and (C) in the multilayer resist pattern A method of forming a plated article comprising the step of performing a plating treatment in the method, wherein the negative photoresist composition comprises (a) an alkali-soluble resin and (b) an acid generator. delete (A) forming a layer of negative photoresist composition, and then heating and subsequently exposing the layer, and then heating or not heating, (B) the step (A) such that step (A) is performed a total of two or more times Repeatedly stacking the negative photoresist layer and then developing all of the layers simultaneously to form a multilayer resist pattern, and (C) performing a plating process in the multilayer resist pattern. A molding method, wherein the negative photoresist composition comprises (a) an alkali soluble resin, (b) an acid generator, and (c) a crosslinking agent, an organic solvent, a quencher, a surfactant, an adhesion aid, and a soluble control component in an alkaline developer. At least one component selected from the group.

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