JP5216413B2 - Three-dimensional structure having conductive layer and method of manufacturing three-dimensional metal structure - Google Patents

Description

  The present invention relates to a three-dimensional structure having a conductive layer and a method for manufacturing a three-dimensional metal structure.

  In recent years, formation by a thick film lithography method and a plating method has attracted attention in a method for forming a microstructure or a micropart represented by a MEMS (MICRO ELECTRO MECHANICAL SYSTEMS). As a method of forming such a three-dimensional structure of a microstructure or a minute part, a method of forming a stepped recess by forming a single photoresist layer, selectively exposing and developing is known. . However, as the structure of the minute structure or minute part becomes complicated, it has become necessary to form a stepped recess having a more complicated shape.

  The following method has been proposed as a method for manufacturing such a stepped recess. That is, first, as shown in FIG. 2 (a), a negative photoresist composition containing a current-carrying metal layer 12 on a substrate 11 and further containing an alkali-soluble resin, an acid generator, and other components. After coating, it is exposed. Next, this process is performed a plurality of times, and after a plurality of the negative photoresist resin layers 13 and 14 are stacked, a multilayer resin pattern is formed by developing all the layers simultaneously, and the multilayer resin pattern is plated. Thus, a three-dimensional metal structure is formed (Patent Document 1).

Further, as a process before performing the plating process, as shown in FIG. 2B, for example, in a resin pattern having two layers, after forming the conductive layer 15 by vapor-depositing gold on the entire surface of the resin pattern, the negative type The conductive layer on the upper surface of the photoresist resin layer 14 is mechanically ground and removed to be processed into the shape shown in FIG. 2C, and the recess 16 is subjected to a plating treatment as shown in FIG. After filling with the metal 17, the three-dimensional metal structure 18 such as the hollow wiring shown in FIG. 2E can be formed by removing the resin layer (Non-patent Document 1).
JP 2006-17969 A Dr. Koichi Misumi Doctoral Thesis (Kanto Gakuin University) January 2008 ("Application of photolithography and plating technology for processing and mounting of MEMS devices") pages 36-37

  However, in the above method of removing a part of the conductive layer by mechanical grinding after forming the conductive layer by gold deposition, the cost of introducing a deposition apparatus and gold for deposition is large, and the size of the substrate to be used However, there are problems such as being limited by the size of the vapor deposition apparatus. Furthermore, mechanical grinding for removing gold vapor deposition requires manual grinding for each part formed on the substrate, and is not suitable for mass production. In addition to this, there is a possibility of deformation or cracking of the resin pattern during mechanical grinding, mixing of grinding residue into the resin pattern recess, and the like.

  The present invention has been made in view of the above circumstances, and can form a conductive layer without using a complicated and expensive vapor deposition method, and can efficiently remove a part of the conductive layer while preventing the occurrence of defective products. An object of the present invention is to provide a three-dimensional structure having a conductive layer and a method for producing a three-dimensional metal structure.

  The present inventors have found that the above problem can be solved by forming a conductive layer by electroless plating, and then removing a part of the conductive layer by etching treatment, and have completed the present invention. Specifically, the present invention provides the following.

  The present invention provides, as a first aspect, (A) a step of forming a patterned organic film on a substrate, (B) a step of forming a conductive layer on the surface of the patterned organic film by electroless plating, and (C And a step of removing a part of the conductive layer by an etching process, and a method for producing a three-dimensional structure having a conductive layer.

  In the present invention, as a second embodiment, (A) a step of forming a patterned organic film on a substrate, (B) a step of forming a conductive layer on the surface of the patterned organic film by electroless plating, and (C There is provided a method for producing a three-dimensional metal structure, comprising: a step of removing a part of the conductive layer by etching treatment; and a step of (D) plating treatment and peeling of the patterned organic film.

  According to the present invention, a conductive layer can be formed without using a complicated and expensive vapor deposition method, and a part of the conductive layer can be efficiently removed while preventing generation of defective products. Thereby, a three-dimensional structure can be manufactured easily. Furthermore, a three-dimensional metal structure can be manufactured by subjecting the three-dimensional structure to a plating treatment and peeling the patterned organic film.

Hereinafter, embodiments of the present invention will be described.
The manufacturing method of the three-dimensional structure according to the present invention includes (A) a step of forming a patterned organic film on a substrate, and (B) a step of forming a conductive layer on the surface of the patterned organic film by electroless plating. (C) removing a part of the conductive layer by an etching process. Hereafter, each process is demonstrated, referring FIG. 1 as needed.

<< (A) Step of Forming Patterned Organic Film on Substrate >>
(A) In the step of forming a patterned organic film on a substrate (hereinafter also referred to as “(A) step”), first, an organic compound or an organic resin is formed on the substrate 1 shown in FIG. An organic film is formed by removing the solvent after coating on the organic film 3 or transferring an organic compound or organic resin processed into a sheet shape. Next, a patterned organic film is formed by a conventionally known method such as an optical modeling method, a photolithographic method, a thermal imprint method, or a photoimprint method. For example, in the stereolithography method, the patterned organic film is obtained by curing and laminating a liquid ultraviolet curable resin (liquid that reacts and cures with ultraviolet rays) using an ultraviolet laser of an optical modeling apparatus. Precise 3D objects can be created. In the photolithography method, an organic film is selectively exposed through a mask and then developed. In the optical imprint method, the mold material is pressed against the organic film, irradiated with light, It is formed by separating from the organic film. In the thermal imprint method, the organic film is heated, the mold material is pressed against the organic film, the substrate is cooled while maintaining the pressed state, the organic film is cured, and then the mold material is separated from the organic film. Is formed. The material of the organic film is not particularly limited, but an optical lithography method using a photoresist composition is preferable. Hereinafter, the aspect of the photolithography method using the photoresist composition will be described.

<Formation method of organic film>
The organic film can be formed by applying a photoresist composition on a substrate by a conventionally known method. The photoresist composition will be described later. Although it does not specifically limit as a board | substrate, For example, the board | substrate with which those substrates, such as a silicon | silicone, gold | metal | money, copper, nickel, palladium, etc. or those metal layers 2 were formed is mentioned. Examples of the coating method include spin coating, slit coating, roll coating, screen printing, and applicator methods. The photoresist composition thus applied to a desired thickness is heated to remove the solvent, thereby forming a desired organic film.

<Heating method>
The heating condition of the organic film formed using the photoresist composition varies depending on the type of each component in the composition, the blending ratio, the coating film thickness, etc., but is usually 70 to 140 ° C., preferably 80 to 120 ° C. It is preferably about 2 to 60 minutes. As a heating method, methods such as a hot plate method and an oven method can be employed.

  Alternatively, the organic film may be transferred onto the substrate using a dry film obtained by laminating a photoresist composition on a support film instead of the coating method described above. Such a dry film can be produced by a conventionally known method as described below.

<Dry film>
The dry film used in the present invention is an organic film formed by applying a photoresist composition on a support film to form a coating film and drying the coating film. The dry film thus formed is used to form a patterned organic film on the substrate in step (A). The dry film is protected by a protective film that can easily peel off the surface of the organic film, and is easy to store, transport and handle, and has high film flatness to facilitate the formation of the organic film on the substrate. To do.

  As the support film used in the production of the dry film, each layer formed on the support film can be easily peeled off from the support film, and can be used without any limitation as long as each layer can be transferred onto the glass substrate. Examples thereof include a flexible film made of a synthetic resin film such as 15 to 125 μm of polyethylene terephthalate, polyethylene, polypropylene, polycarbonate, or polyvinyl chloride. It is preferable that the support film is subjected to a release treatment as necessary so that transfer is easy.

  In forming the organic film on the support film, a photoresist composition is prepared and the above composition is applied on the support film by a conventional method.

  After the coating film is dried, a protective film is preferably adhered to the surface of the organic film in order to stably protect the organic film when not in use. As this protective film, a polyethylene terephthalate film, a polypropylene film, a polyethylene film, or the like having a thickness of about 15 to 125 μm coated or baked with silicone is suitable.

When using the dry film thus formed, the protective film laminated on the surface of the organic film is peeled off, and the exposed organic film is overlaid on the surface of the substrate or the already formed organic film. Adhesion and pressure bonding with. For example, the organic film is thermocompression bonded to the surface of the substrate by a known method by moving a heating roller. Thereafter, the support film is peeled off to expose the organic film on the surface, thereby forming the organic film. The thermocompression bonding is preferably performed by heating the surface temperature of the substrate to 80 to 140 ° C., in a range of a roll pressure of 1 to 5 kg / cm ² and a moving speed of 0.1 to 10.0 m / min. The substrate may be preheated, and the preheating temperature is preferably in the range of 40 to 100 ° C., for example.

  In the present invention, the thickness of the organic film single layer is 5 to 2000 μm, preferably 10 to 1000 μm, and more preferably 20 to 500 μm. The organic film may be further laminated to have multiple layers according to the shape of the finally obtained three-dimensional metal structure.

<Exposure method>
By irradiating the obtained coating film with radiation, for example, ultraviolet rays having a wavelength of 300 to 600 nm or visible light through the entire surface or a mask having a predetermined pattern, only the pattern portion that forms the entire surface or a three-dimensional metal structure is applied. Selective exposure. As these radiation sources, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, an argon gas laser, or the like can be used. Here, the radiation means ultraviolet rays, visible rays, far ultraviolet rays, X-rays, electron beams, and the like. The amount of radiation irradiation varies depending on the type of each component in the composition, the blending amount, the film thickness of the coating film, etc., but is, for example, 20 to 3000 mJ / cm ² when using an ultrahigh pressure mercury lamp. When a dry film is used, the exposure is performed after the support film is peeled in principle. However, when the support film has transparency to exposure light, the exposure treatment can be performed before the support film is peeled off.

  After the exposure, if necessary, heating (POST EXPOSURE BAKE) may be performed using the above-described method. Although it does not specifically limit as a heating method, Since a heat | fever transfers uniformly, it is preferable.

<Development method>
Next, the organic film is subjected to development by a known method to form a patterned organic film. As a developing method after irradiation, an alkaline aqueous solution is used as a developing solution, and unnecessary portions are dissolved and removed, and only the portions not irradiated with radiation are dissolved and removed. Examples of the developer include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, dimethyl. Ethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5,4,0] -7-undecene, 1,5-diazabicyclo [4,3,0 An aqueous solution of an alkali such as -5-nonane can be used. An aqueous solution obtained by adding an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant to the alkaline aqueous solution can also be used as a developer.

  The development time varies depending on the type of each component of the composition, the blending ratio, and the dry film thickness of the composition, but it is usually 1 to 30 minutes, and the development method is a liquid piling method, dipping method, paddle method, spray development method. Any of these may be used. After the development, washing with running water is performed for 30 to 90 seconds and air-dried using an air gun or the like, or dried in an oven.

  After development, heating (post-bake) may be performed as necessary. Although it does not specifically limit as a heating method, A hotplate and an oven method are mentioned.

  As described above, a single-layer patterned organic film can be formed on the substrate. When forming a multilayer patterned organic film, it is as follows.

<Formation of multilayer patterned organic film>
The step of forming the multilayer patterned organic film includes a step of forming and exposing an organic film on the substrate (hereinafter, also referred to as “(A-1) step”) and the step (A-1) two or more times in total. After repeatedly stacking the patterned organic films, a step of forming a multilayer patterned organic film by developing all the layers simultaneously (hereinafter also referred to as “(A-2) process”) is included. . As a material for the organic film, a negative photoresist composition is preferred. By using a negative photoresist composition, the exposed portion of the photoresist layer is hardened by heating after the step (A-1), and the photoresist layers can be stacked without distortion. Is 2 layers or more, preferably 2 to 20 layers, more preferably 2 to 10 layers. The total thickness of the stacked photoresist layers is 10 μm or more, preferably 20 to 1000 μm.

  In this invention, it is preferable that the exposure in the said (A-1) process is pattern formation exposure process through the pattern mask in all the photoresist layers. By doing so, it is possible to obtain a multilayer photoresist layer that does not include the entire surface exposure layer.

  A form in which the exposure area of the exposure in the step (A-1) is larger in the exposure area of the layer far from the exposure light source than the exposure area of the layer near the exposure light source is more preferable. This increases the shape stability of the multilayer resist pattern and facilitates plating.

  Moreover, the form from which a pattern shape differs for every photoresist layer is also possible. Thereby, the three-dimensional shape from which a shape differs in a film thickness direction can be formed with a three-dimensional metal structure.

  The stacked organic films are subjected to development by a known method, and all the organic films are developed simultaneously to form a multilayer patterned organic film. The developer, development method, development time, and drying method after development are as described above.

<< (B) Step of Forming Conductive Layer on Patterned Organic Film Surface by Electroless Plating >>
In the step of forming a conductive layer on the surface of the patterned organic film by electroless plating (hereinafter, also referred to as “(B) step”), the substrate is immersed in a conventionally known electroless plating solution, so that FIG. Is formed on the multilayer patterned organic film. The electroless plating solution contains a metal salt, a reducing agent, and an additive. As the metal salt, sulfate, acetate, carbonate and the like are used. In the present invention, the metal species forming the conductive layer is not particularly limited, but copper or nickel is preferable. The step of forming the conductive layer by electroless plating, that is, the electroless plating treatment step preferably includes an electroless copper plating step or an electroless nickel plating step subsequent to the cleaning step and the catalyzing treatment step.
In addition, as a pre-process of (B) process, you may perform the hydrophilic treatment of the photoresist layer surface as needed. Plating is facilitated by performing the hydrophilic treatment. Examples of the hydrophilic treatment include an ashing treatment using a known method.

<Washing process>
First, the substrate provided with the patterned organic film is immersed in a phosphoric acid solution for cleaning. As the phosphate solution, sodium phosphate or the like is used. The immersion time is preferably 30 to 180 seconds, and more preferably 45 to 90 seconds. After the treatment, it is preferable to carry out water immersion cleaning in 3 to 5 stages.

<Catalytic treatment process>
The substrate that has undergone the cleaning step is immersed in an aqueous tin chloride (SnCl ₂ ) solution having a predetermined concentration for a predetermined time. The concentration of tin chloride is ^preferably from ^{0.01g / dm 3 ~0.10g / dm 3} , 0.03g / dm 3 ~0.07g / dm 3 are more preferred. Further, the immersion time is preferably 15 to 180 seconds, and more preferably 30 to 60 seconds. After the treatment, it is preferable to carry out water immersion cleaning in 3 to 5 stages.

Next, the substrate immersed in a tin chloride (SnCl ₂ ) aqueous solution for a predetermined time and then washed with water is immersed in an aqueous palladium chloride (PdCl ₂ ) solution having a predetermined concentration for a predetermined time. The concentration of palladium chloride is ^preferably from ^{0.01g / dm 3 ~0.3g / dm 3} , 0.03g / dm 3 ~0.07g / dm 3 are more preferred. Further, the immersion time is preferably 15 to 180 seconds, and more preferably 30 to 60 seconds. After the treatment, it is preferable to carry out water immersion cleaning in 3 to 5 stages.

<Electroless copper plating process>
The substrate that has undergone the catalyzing treatment step is immersed in a copper plating bath to perform copper plating. After copper plating, the substrate is washed with water in 3 to 5 stages and dried using an air gun, oven, or the like. A conventionally well-known thing is used as a copper plating bath. For example, 0.02 M to 0.10 M of copper sulfate, 0.10 M to 0.40 M of formalin, 1.0 ppm to 20.0 ppm of 2,2′-bipyridyl, and 50.0 ppm of surfactant (polyethylene glycol, etc.) An example is a copper plating bath containing ˜500 ppm and a complexing agent of 0.20 M to 0.40 M. As the complexing agent, an ethylene-amine complexing agent is preferably used. The temperature of the copper plating bath is preferably 50 ° C to 70 ° C, and the pH is preferably 11.5 to 12.5. Moreover, it is preferable to perform stirring by air ventilation. For adjusting the pH, potassium hydroxide and sulfuric acid are used.

<Electroless nickel plating process>
Nickel plating is performed by immersing the substrate that has undergone the catalyzing step in a nickel plating bath. After nickel plating, the substrate is subjected to immersion cleaning in 3 to 5 stages and dried using an air gun, oven, or the like. A conventionally known nickel plating bath is used. For example, nickel sulfate 0.05M-0.20M, sodium hypophosphite 0.10M-0.30M, lead ions 0.05ppm-0.30ppm, complexing agent 0.05M-0.30M An example is a nickel plating bath. As the complexing agent, a complexing agent of carboxylic acids is preferably used. The temperature of the nickel plating bath is preferably 50 ° C to 70 ° C, and the pH is preferably 4.0 to 5.5. Sodium hydroxide and sulfuric acid are used to adjust the pH.

  The conductive layer thus formed is preferably from 0.01 to 2 μm, more preferably from 0.05 to 1 μm, and most preferably from 0.05 to 0.5 μm.

<< (C) Step of Removing Part of the Conductive Layer by Etching Process >>
In the step of removing a part of the conductive layer by etching treatment (hereinafter also referred to as “(C) step”), the conductive layer formed as described above is removed by contacting with an etching solution. The conductive layer to be removed is determined according to the shape of the three-dimensional metal structure as a final product. For example, when forming the bridge-shaped three-dimensional metal structure 9 shown in FIG. It is preferable to remove only the conductive layer 5 on the upper surface of the organic film 4 shown in FIG. 1B, that is, the conductive layer formed on the surface other than the inner wall of the recess 7 and the bottom surface of the recess 7. By selectively removing a part of the conductive layer in this way, only the concave portion can be filled with metal (filling) in the plating process of the next step. The etching solution 6 is not particularly limited as long as it dissolves the metal species of the conductive layer, and a conventionally known one can be used. Examples of such an etchant include perhydrosulfuric acid, persulfuric acid, hydrochloric acid, nitric acid, cyanine, and organic etchants. By removing a part of the conductive layer by etching, it is possible to change conditions such as the composition, concentration, temperature, etching time, immersion tank size, etc. of the etching solution according to the metal species of the conductive layer. A substrate having conductive layers of various sizes and thicknesses can be processed efficiently. Furthermore, since mechanical grinding is not performed, there is no possibility that the grinding residue is mixed into the recess 7 or the organic film is deformed or cracked.

  In the step (C), when the etching solution and the conductive layer are brought into contact with each other, only the conductive layer to be removed is exposed, and other portions of the conductive layer are protected from coming into contact with the etching solution, thereby protecting a part of the conductive layer. However, in the present invention, as shown in FIG. 1C, the conductive layer is brought into contact with the etchant so that only the conductive layer on the surface of the uppermost organic film is exposed. It is preferable to contact with an etching solution. By contacting in this way, the recess 7 is filled with a gas (mainly hydrogen) generated by the reaction between the metal of the conductive layer and the etchant, and the etchant hardly penetrates into the recess. Thereby, as shown in FIG. 1D, only the conductive layer on the uppermost organic film can be selectively etched without protecting other portions of the conductive layer from the etching solution. In this way, it is possible to selectively form a conductive layer necessary for performing the plating process described later.

<< (D) Process of Plating and Stripping Patterned Organic Film >>
In the present invention, as shown in FIG. 1 (e), the recess 7 is plated with a plating metal 8 by subjecting it to a step (hereinafter also referred to as “(D) step”) for further plating treatment and peeling of the patterned organic film. Fill with (filling). In the step (D), conventionally known various plating methods such as electrolysis and electroless plating can be selected and used as desired. Further, as the plating metal 8, gold, copper, solder, nickel or the like can be selected as necessary.

  After the plating process, the patterned organic film is peeled off by a conventionally known peeling method. For example, a cleaning method after incineration of the organic film, a peeling method by bringing a known stripping liquid composition into contact with the organic film (immersion, etc.), and the like can be employed. In particular, the peeling method is preferable from the viewpoint of process easiness and damage to the three-dimensional metal structure. As a peeling method of the organic film, a dipping method, a dipping method, a shower method, ashing, or a combination thereof can be employed. You may make an ultrasonic wave act at the time of peeling. Thus, after peeling an organic film from a board | substrate, it wash | cleans and drys according to a conventional method.

  Through the above steps, a three-dimensional metal structure 9 having a height of 10 μm or more is formed on the substrate as shown in FIG.

<Photoresist composition>
The photoresist composition is not particularly limited as long as a resist pattern can be formed. When a single-layer patterned organic film is formed, either a positive photoresist composition or a negative photoresist composition may be used. However, when a multilayer patterned organic film is formed, it is easy to stack the negative organic film. Type photoresist compositions are preferred. Of the negative photoresist compositions, a chemically amplified negative photoresist composition is preferred. Examples of such a chemically amplified negative photoresist composition include chemically amplified negative photoresist compositions for thick films described in JP-A-2008-107635 and Patent Document 1. The components of the negative photoresist composition are described below.

{Alkali-soluble resin (a)}
The alkali-soluble resin (hereinafter also referred to as “component (a)”) is not particularly limited as long as it is a resin that is generally used as a base resin for negative-type chemically amplified photoresists. Accordingly, it can be arbitrarily selected from conventionally known ones. For example, a resin having a novolac resin, a polyhydroxystyrene resin, or an acrylic resin as a main component is generally widely used because of its good characteristics such as resist shape and resolution. A particularly preferred component (a) is a novolak resin. By using a novolac resin as a main component, the peelability is good and excellent plating resistance is obtained.

[Novolac resin]
The novolak resin can be obtained, for example, by addition condensation of an aromatic compound having a phenolic hydroxyl group (hereinafter simply referred to as “phenols”) and an aldehyde under an acid catalyst. In this case, 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, phloroglicinol, hydroxydiphenyl, bisphenol A, gallic acid, gallic acid ester, α-naphthol, β-naphthol, etc. The

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

  The catalyst for the addition condensation reaction is not particularly limited. For example, hydrochloric acid, nitric acid, sulfuric acid, formic acid, oxalic acid, acetic acid and the like are used as the acid catalyst.

  The novolak resin is also preferably a novolak resin composed of cresol, xylenol or trimethylphenol. More preferably, the m-cresol novolak resin obtained by condensing m-cresol and aldehydes has a particularly good development profile and is preferred.

  The novolak resin has a mass average molecular weight of 3000 to 50000, preferably 5000 to 30000. When the mass average molecular weight is less than 3000, the cured portion film tends to decrease (thinner) after development, and when the mass average molecular weight exceeds 50000, a residue tends to remain after development.

〔acrylic resin〕
The acrylic resin is not particularly limited, but contains (a1) a structural unit derived from a polymerizable compound having an ether bond and / or (a2) a structural unit derived from a polymerizable compound having a carboxyl group. Is preferred.

  (A1) As the polymerizable compound having an ether bond, 2-methoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethyl carbitol (meth) acrylate, phenoxypolyethylene Examples include (meth) acrylic acid derivatives having an ether bond and an ester bond such as glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, and tetrahydrofurfuryl (meth) acrylate, and preferably 2-methoxy Ethyl acrylate and methoxytriethylene glycol acrylate. These compounds can be used alone or in combination of two or more.

  (A2) Examples of the polymerizable compound having a carboxyl group include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid, 2-methacryloyloxyethyl succinic acid, 2- Examples include methacryloyloxyethylmaleic acid, 2-methacryloyloxyethylphthalic acid, 2-methacryloyloxyethylhexahydrophthalic acid and other compounds having a carboxyl group and an ester bond, preferably acrylic acid and methacrylic acid. is there. These compounds can be used alone or in combination of two or more.

  The content of the structural unit derived from the polymerizable compound (a1) having an ether bond in the acrylic resin is preferably 30 to 90% by mass, more preferably 40 to 80% by mass. If it exceeds 90% by mass, the compatibility with the resin solution tends to be poor, and a uniform resist film tends not to be obtained during pre-baking, and if it is less than 30% by mass, cracks tend to occur during plating.

  The content of the structural unit derived from the polymerizable compound (a2) having a carboxyl group in the acrylic resin is preferably 2 to 50% by mass, and more preferably 5 to 40% by mass. When it is less than 2% by mass, the alkali solubility of the acrylic resin is lowered, and sufficient developability cannot be obtained. In addition, the peelability is lowered and a resist film is left on the substrate. When it exceeds 50 mass%, there is a tendency that the remaining film ratio after development and the plating resistance are deteriorated.

[Polyhydroxystyrene resin]
Examples of the polyhydroxystyrene resin include radical polymers or ions consisting only of hydroxystyrene constituent units such as hydroxystyrene such as p-hydroxystyrene, α-alkylhydroxystyrene such as α-methylhydroxystyrene and α-ethylhydroxystyrene. Examples thereof include a polymer and a copolymer composed of the hydroxystyrene structural unit and other structural units. The ratio of the hydroxystyrene structural unit in the polymer is preferably 1% by mass or more, more preferably 10 to 30% by mass. This is because if the ratio of the hydroxystyrene structural unit is less than 10% by mass, developability and resolution tend to be lowered.

  The mass average molecular weight of the polymer having a hydroxystyrene structural unit is preferably 5000 or less, more preferably 2000 or more and 4000 or less. This is because when the mass average molecular weight exceeds 5000, the resolution tends to decrease.

  A monomer that forms a constituent unit other than the hydroxystyrene constituent unit is preferably a monomer in which the hydroxyl group of the hydroxystyrene constituent unit is substituted with another group or a monomer having an α, β-unsaturated double bond.

  As another group for substituting the hydroxyl group of the hydroxystyrene structural unit, an alkali dissolution inhibiting group that is not dissociated by the action of an acid is used. Examples of the alkali dissolution inhibiting group that does not dissociate by the action of an acid include a substituted or unsubstituted benzenesulfonyloxy group, a substituted or unsubstituted naphthalenesulfonyloxy group, a substituted or unsubstituted benzenecarbonyloxy group, and a substituted or unsubstituted naphthalenecarbonyl. Specific examples of the substituted or unsubstituted benzenesulfonyloxy group include benzenesulfonyloxy group, chlorobenzenesulfonyloxy group, methylbenzenesulfonyloxy group, ethylbenzenesulfonyloxy group, propylbenzenesulfonyloxy group, methoxy group, and the like. A benzenesulfonyloxy group, an ethoxybenzenesulfonyloxy group, a propoxybenzenesulfonyloxy group, an acetaminobenzenesulfonyloxy group, etc., and a substituted or unsubstituted naphthalenesulfonyl Specific examples of the xy group include naphthalenesulfonyloxy group, chloronaphthalenesulfonyloxy group, methylnaphthalenesulfonyloxy group, ethylnaphthalenesulfonyloxy group, propylnaphthalenesulfonyloxy group, methoxynaphthalenesulfonyloxy group, ethoxynaphthalenesulfonyloxy group, propoxynaphthalene group A sulfonyloxy group, an acetaminonaphthalenesulfonyloxy group, and the like are preferable. Furthermore, examples of the substituted or unsubstituted benzenecarbonyloxy group and the substituted or unsubstituted naphthalenecarbonyloxy group include those in which the substituted or unsubstituted sulfonyloxy group is replaced with a carbonyloxy group. Of these, an acetaminobenzenesulfonyloxy group or an acetaminonaphthalenesulfonyloxy group is preferable.

  Specific examples of the monomer having an α, β-unsaturated double bond include styrene monomers such as styrene, chlorostyrene, chloromethylstyrene, vinyltoluene, α-methylstyrene, methyl acrylate, methyl methacrylate, methacrylic acid. Examples include acrylic acid monomers such as phenyl, monomers such as vinyl acetate and vinyl benzoate, among which styrene is preferable.

  Examples of the polymer having a hydroxystyrene structural unit include copolymers obtained from hydroxystyrene and styrene, such as poly (4-hydroxystyrene-styrene) copolymer, poly (4-hydroxystyrene-methylstyrene) copolymer. A coalescence or the like is preferable because it exhibits high resolution and high heat resistance.

  (A) A component may be used individually, respectively, or 2 or more types may be mixed and used for it. When the component (a) is composed of a mixed resin containing a novolac resin and / or an acrylic resin and a polymer having a hydroxystyrene structural unit, the novolac resin and / or the acrylic resin, with the total of each component being 100 parts by mass Is 50 to 98 parts by mass, preferably 55 to 95 parts by mass, and the polymer having a hydroxystyrene structural unit is 50 to 2 parts by mass, preferably 45 to 5 parts by mass. Such a blending ratio is preferable because both developability and resolution are improved. The component (a) is 30 to 99 parts by mass, preferably 65 to 95 parts per 100 parts by mass of the total solid content of the components (a) to (c) (the components (b) and (c) will be described later). It can contain in the range of a mass part. When the component (a) is less than 50 parts by mass, the plating solution resistance, the plating shape, and the peelability may be deteriorated, and when it exceeds 99 parts by mass, development failure may occur during development.

{Acid generator (b)}
The acid generator (hereinafter also referred to as “component (b)”) is not particularly limited as long as it is a compound that generates an acid directly or indirectly by light. Specifically, 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 (trichloromethyl) -6- [2- (3-methoxy-5- Propoxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (3,4-methylenedioxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) ) -6- (3,4-methylenedioxyphenyl) -s-triazine, 2,4-bis-trichloromethyl-6- (3-bromo-4methoxy) phenyl-s-tria 2,4-bis-trichloromethyl-6- (2-bromo-4methoxy) phenyl-s-triazine, 2,4-bis-trichloromethyl-6- (2-bromo-4methoxy) styrylphenyl-s -Triazine, 2,4-bis-trichloromethyl-6- (3-bromo-4methoxy) 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-methylenedioxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, tris (1, Halogen-containing triazine compounds such as 3-dibromopropyl) -1,3,5-triazine, tris (2,3-dibromopropyl) -1,3,5-triazine, and tris (2,3-dibromopropyl) isocyanurate A halogen-containing triazine compound represented by the following general formula:

(Wherein R ^{1 to} R ³ may be the same or different and each represents a halogenated alkyl group)

α- (p-toluenesulfonyloxyimino) -phenylacetonitrile, α- (benzenesulfonyloxyimino) -2,4-dichlorophenylacetonitrile, α- (benzenesulfonyloxyimino) -2,6-dichlorophenylacetonitrile, α- (2 -Chlorobenzenesulfonyloxyimino) -4-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, a compound represented by the following general formula;

(In the formula, R ⁴ represents a monovalent to trivalent organic group, R ⁵ represents a substituted, unsubstituted saturated hydrocarbon group, an unsaturated hydrocarbon group or an aromatic compound group, and n is 1 to 3. An aromatic compound group refers to a group of a compound exhibiting physical and chemical properties unique to an aromatic compound, such as an aromatic hydrocarbon group such as a phenyl group or a naphthyl group, or furyl. A heterocyclic group such as a group, a thienyl group, etc. These may have one or more suitable substituents such as a halogen atom, an alkyl group, an alkoxy group, a nitro group, etc. on the ring. ⁵ is particularly preferably an alkyl group having 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, and a butyl group, particularly preferably a compound in which R ⁴ is an aromatic compound group and R ⁵ is a lower alkyl group. As an acid generator represented by the above general formula, n = 1 When, R ⁴ is a phenyl group, methylphenyl group, be any of the methoxyphenyl group, the compound of R ⁵ is a methyl group, specifically alpha-(methylsulfonyl) -1- phenylacetonitrile, alpha- Examples include (methylsulfonyloxyimino) -1- (p-methylphenyl) acetonitrile and α- (methylsulfonyloxyimino) -1- (p-methoxyphenyl) acetonitrile, when n = 2, Specific examples of the acid generator include acid generators represented by the following chemical formula.

  Bissulfonyldiazomethanes such as bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane; p-toluenesulfone Nitrobenzyl derivatives such as acid 2-nitrobenzyl, p-toluenesulfonic acid 2,6-dinitrobenzyl, nitrobenzyl tosylate, dinitrobenzyl tosylate, nitrobenzyl sulfonate, nitrobenzyl carbonate, dinitrobenzyl carbonate; pyrogallol trimesylate , Pyrgallol tritosylate, benzyl tosylate, benzyl sulfonate, N-methylsulfonyloxysuccinimide, N-trichloromethylsulfonyloxysk Sulfonic acid esters such as N-imide, N-phenylsulfonyloxymaleimide, N-methylsulfonyloxyphthalimide; diphenyliodonium hexafluorophosphate, (4-methoxyphenyl) phenyliodonium trifluoromethanesulfonate, bis (p-tert-butylphenyl) iodonium Onium salts such as trifluoromethanesulfonate, triphenylsulfonium hexafluorophosphate, (4-methoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, (p-tert-butylphenyl) diphenylsulfonium trifluoromethanesulfonate; benzoin tosylate, α-methylbenzoin Benzoin tosylate such as tosylate; other diphenyliodonium salts, Examples include triphenylsulfonium salt, phenyldiazonium salt, benzyl carbonate and the like. In particular, triazine compounds can be preferably used because of their high performance as an acid generator by light and good solubility even when a solvent is used. Among them, bromo-containing triazine compounds, particularly 2,4-bis-trichloromethyl-6- (3-bromo-4methoxy) phenyl-s-triazine, 2,4-bis-trichloromethyl-6- (3-bromo-4 -Methoxy) styryl-s-triazine and tris (2,3-dibromopropyl) isocyanurate can be preferably used. The acid generator as the component (b) may be used alone or in combination of two or more.

The component (b) is 0.01 to 5 parts by mass, preferably 0.05 to 2 parts by mass, more preferably 0.1 to 0.1 parts by mass with respect to 100 parts by mass of the total solid content of the components (a) to (d). It can contain in the range of 1 mass part. When the component (b) is less than 0.01 parts by mass, the cross-linking and curing by heat or light is not sufficiently performed, resulting in a decrease in plating resistance, chemical resistance and adhesion of the resulting thick film, and the formed plating shape. May be defective. If it exceeds 5 parts by mass, development failure may occur during development.
{Plasticizer (c)}
In addition to the components (a) to (b), a plasticizer (hereinafter also referred to as “component (c)”) may be blended as necessary. By including a plasticizer, generation of cracks can be suppressed.
Furthermore, in this invention, it is preferable that mass ratio of (a) component mentioned above and (c) component is the range of 5: 95-95: 5.
As said (c) component, at least 1 sort (s) chosen from an acrylic resin and a polyvinyl resin can be used.

[(C-1) Acrylic resin]
The acrylic resin (c-1) preferably has a mass average molecular weight of 50,000 to 800,000.
Such an acrylic resin preferably contains a monomer derived from a polymerizable compound having an ether bond and a monomer derived from a polymerizable compound having a carboxyl group.
Examples of the polymerizable compound having an ether bond include 2-methoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethyl carbitol (meth) acrylate, phenoxypolyethylene glycol ( Examples include (meth) acrylic acid derivatives having an ether bond and an ester bond such as (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, and preferably 2-methoxyethyl acrylate. And methoxytriethylene glycol acrylate. These compounds can be used alone or in combination of two or more.
Examples of the polymerizable compound having a carboxyl group include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid, 2-methacryloyloxyethyl succinic acid, and 2-methacryloyloxy. Examples thereof include compounds having a carboxyl group and an ester bond such as ethylmaleic acid, 2-methacryloyloxyethylphthalic acid and 2-methacryloyloxyethylhexahydrophthalic acid, and acrylic acid and methacrylic acid are preferred. These compounds can be used alone or in combination of two or more.

[(C-2) polyvinyl resin]
The polyvinyl resin (c-2) preferably has a mass average molecular weight of 10,000 to 200,000.
As such a polyvinyl resin, poly (vinyl lower alkyl ether) is preferable, and it can be obtained by polymerizing a vinyl lower alkyl ether represented by the following general formula (c1) alone or a mixture of two or more kinds (co). It consists of a polymer.

In the above general formula (c1), R ^1c is a linear or branched alkyl group having 1 to 6 carbon atoms.
Such a polyvinyl resin is a polymer obtained from a vinyl-based compound. Specific examples of such a polyvinyl resin include polyvinyl chloride, polystyrene, polyhydroxystyrene, polyvinyl acetate, polyvinyl benzoic acid, polyvinyl Examples include methyl ether, polyvinyl ethyl ether, polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl phenol, and copolymers thereof. Among these, polyvinyl methyl ether is preferable in view of the low glass transition point.

{Other components (d)}
Examples of other components (hereinafter also referred to as “component (d)”) include a crosslinking agent. As the crosslinking agent, amino compounds such as melamine resin, urea resin, guanamine resin, glycoluril-formaldehyde resin, succinylamide-formaldehyde resin, ethyleneurea-formaldehyde resin, and the like can be used. An alkoxymethylated amino resin such as a methylated urea resin can be suitably used. The alkoxymethylated amino resin is obtained by, for example, condensing a condensate obtained by reacting melamine or urea with formalin in a boiling aqueous solution with a lower alcohol such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, or isopropyl alcohol. And then the reaction solution is cooled and precipitated. 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, and propoxymethyl. And urea-oxygenated resin, butoxymethylated urea resin, and the like. The said alkoxymethylated amino resin can be used individually or in combination of 2 or more types. In particular, an alkoxymethylated melamine resin is preferable because it can form a stable resist pattern with a small dimensional change of the resist pattern with respect to a change in radiation dose. Among these, methoxymethylated melamine resin, ethoxymethylated melamine resin, propoxymethylated melamine resin and butoxymethylated melamine resin are preferable. The said crosslinking agent component can be contained in 1-30 mass parts with respect to 100 mass parts of solid content total amount of (a)-(c) component, Preferably it is 5-20 mass parts. When the component (c) is less than 1 part by mass, the resulting thick film may have poor plating resistance, chemical resistance and adhesion, and the formed plating shape may be poor. If it exceeds 30 parts by mass, development failure may occur during development.

  Furthermore, an organic solvent can be appropriately blended for viscosity adjustment. Specific examples of the organic solvent 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 Recall 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, Pyrene glycol monopropyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl 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, 2-hydroxy-2 -Methyl, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, ethyl-3-propoxypropionate, propyl-3-methoxypropionate, isopropyl- 3-methoxypropionate, 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, Examples thereof include ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, benzene, toluene, xylene, cyclohexanone, methanol, ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol, diethylene glycol, and glycerin. These may be used alone or in combination of two or more. The amount of these solvents used is preferably in the range where the solid content concentration is 65% by mass or less in order to obtain a film thickness of 20 μm or more by using the spin coating method for the obtained negative photoresist composition. If the solid content concentration exceeds 65% by mass, the fluidity of the composition is remarkably deteriorated and handling is difficult, and it is difficult to obtain a uniform resist film by the spin coating method.

  In addition to the above components, the negative photoresist composition may contain a quencher such as a secondary or tertiary amine such as triethylamine, tributylamine, dibutylamine, or triethanolamine, if necessary.

  The negative photoresist composition may contain a surfactant as necessary for the purpose of improving coating properties, antifoaming properties, leveling properties and the like. Examples of the surfactant include various anionic, cationic and nonionic surfactants. For example, BM-1000, BM-1100 (manufactured by BM Chemie), MegaFuck F142D, F172, F173, F183 (manufactured by Dainippon Ink and Chemicals), Florard FC-135, FC-170C, FC-430, FC-431 (Sumitomo 3M Co., Ltd.), Surflon S-112, S-113, S-131, S-141, S-145 (Asahi Glass Co., Ltd.), Fluorosurfactants commercially available under the names SH-28PA, -190, -193, SZ-6032, SF-8428 (manufactured by Toray Silicone Co., Ltd.) and the like can be used. The amount of these surfactants used is preferably 5 parts by mass or less with respect to 100 parts by mass of (a) the alkali-soluble resin.

  In the negative photoresist composition, an adhesion aid can be used in order to improve adhesion to the substrate. A functional silane coupling agent is effective as the adhesion aid to be used. Here, the functional silane coupling agent means a silane coupling agent having a reactive substituent such as a carboxyl group, a methacryloyl group, an isocyanate group, and an epoxy group. Specific examples include trimethoxysilylbenzoic acid, γ -Methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and the like. The blending amount is preferably 20 parts by mass or less per 100 parts by mass of (a) alkali-soluble resin.

  In the negative photoresist composition, acetic acid, propionic acid, n-butyric acid, iso-butyric acid, n-valeric acid, iso-valeric acid, benzoic acid, cinnamon are used for fine adjustment of solubility in an alkaline developer. Monocarboxylic acids such as acids; lactic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, salicylic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 2-hydroxycinnamic acid, 3-hydroxycinnamic acid, 4-hydroxy Hydroxy monocarboxylic acids such as cinnamic acid, 5-hydroxyisophthalic acid, syringic acid; 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, pyrome Polyvalent carboxylic acids such as oxalic acid, cyclopentanetetracarboxylic acid, butanetetracarboxylic acid, 1,2,5,8-naphthalenetetracarboxylic acid; itaconic anhydride, succinic anhydride, citraconic anhydride, dodecenyl succinic anhydride, Tricarbanilic anhydride, maleic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hymic anhydride, 1,2,3,4, -butanetetracarboxylic acid, cyclopentanetetracarboxylic dianhydride, phthalic anhydride Acid anhydrides such as pyromellitic anhydride, trimellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bistrimellitic anhydride, and glycerin tris trimellitic anhydride can also be added. Further, N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzylethyl ether, dihexyl ether, acetonylacetone , 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, phenyl cellosolve acetate, etc. A high boiling point solvent can also be added. The amount of the compound used for finely adjusting the solubility in an alkali developer can be adjusted according to the application and application method, and is not particularly limited as long as the composition can be mixed uniformly. , 60% by mass or less, preferably 40% by mass or less, based on the composition obtained.

  Furthermore, a filler, a colorant, a viscosity modifier, etc. can be added to the negative photoresist composition as necessary. Examples of the filler include silica, alumina, talc, bentonite, zirconium silicate, and powdered glass. As colorants, extender pigments such as alumina white, clay, barium carbonate, barium sulfate, etc .; inorganics such as zinc white, lead white, yellow lead, red lead, ultramarine, bitumen, titanium oxide, zinc chromate, bengara, carbon black Pigments; organic pigments such as brilliant 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 scarlet and direct orange; Examples include acid dyes such as yellow. Examples of the viscosity modifier include bentonite, silica gel, aluminum powder and the like.

  An antifoaming agent and other additives can be added to the negative photoresist composition as necessary. Examples of the antifoaming agent include various silicone-based and fluorine-based antifoaming agents. The other components as the component (d) may be used alone or in combination of two or more.

  (D) A component can be contained in 1 mass parts or more with respect to 100 mass parts of solid content total amount, Preferably it is 5 mass parts or more.

<Method for Preparing Negative Photoresist Composition>
The negative photoresist composition can be prepared by mixing and stirring in the usual manner when no filler or pigment is added. When a filler or pigment is added, a dissolver, homogenizer, three roll mill, etc. What is necessary is just to disperse and mix using the disperser of. Moreover, you may further filter using a mesh, a membrane filter, etc. as needed.

  Hereinafter, examples of the present invention will be described. However, these examples are merely examples for suitably explaining the present invention, and do not limit the present invention.

<Example 1>
(A-1) Step: A negative photoresist composition (product name TMMR N-E1000 PM, manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied to the top of a silicon substrate having a gold sputter layer so that the film thickness after heating is 30 μm. Then, it heat-processed for 10 minutes at 120 degreeC using the hotplate. Thereafter, pattern exposure is performed using a test pattern at 2000 mJ / cm ² with an exposure apparatus (product name: Canon PLA501F Hardcontact Canon Inc.), and heat treatment (POST EXPOSER BAKE) is performed at 120 ° C. for 4 minutes using a hot plate. It was.
Step (A-2): Step (A-1) is repeated and the resist layers are stacked, and then developed with a developer (product name: PMER developer P-7G manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23 ° C. for 15 minutes. Thus, a resin layer having a multilayer resist pattern shown in FIG.
(B) Process: The formed resin layer is ashed using an ashing apparatus TCA-3822 (manufactured by Tokyo Ohka Kogyo Co., Ltd.) (output: 400 W, temperature: 40 ° C., pressure: 20 Pa, time: 1 minute, oxygen flow rate) : 200 cc / min), the resin layer was washed with pure water, and degreased using 10 g / l sodium dihydrogen phosphate and 2 g / l surfactant (trade name: NAROACTY, manufactured by Sanyo Chemical Industries) Then, it was immersed in a 0.05 g / l aqueous solution of tin chloride and a 0.05 g / l aqueous solution of palladium chloride. The immersion operation was further repeated twice, and then in an electroless nickel bath (nickel sulfate 0.05 M, glycine 0.15 M, sodium hypophosphite 0.20 M, bismuth 0.1 ppm) at 60 ° C., pH 4.5 Then, electroless plating was performed for 30 minutes.
Step (C): Using an etching solution containing phosphoric acid 80% by mass, nitric acid 8% by mass and water 12% by mass, as shown in FIG. It was immersed in an etching solution (hereinafter also referred to as “opposite immersion”) and etched at room temperature for 40 seconds. After the etching process, running water was washed for 30 seconds and dried using an air gun.
Step (D): In an electric nickel bath (nickel sulfamate 450 g / l, nickel chloride 5 g / l, boric acid 30 g / l, 2-butyne-1,4-diol 0.3 g / l), 40 ° C., pH 4 After performing electroplating for 135 minutes at a current density of 1.0 A / dm ² while stirring with air at 0.0, stripping is performed at 80 ° C. for 1 hour with a stripping solution (product name: stripping 710, manufactured by Tokyo Ohka Kogyo Co., Ltd.). The three-dimensional metal structure shown in FIG. 1 (f) was formed.

<Example 2>
A three-dimensional metal structure was formed in the same manner as in Example 1 except for the following.
In step (B), an electroless copper bath (copper sulfate 0.032M, EDTA.4H 0.240M, formalin 0.200M, 2-2'pipyridyl 100 mass ppm, PEG-1000 (molecular weight) instead of the electroless nickel bath (1000 polyethylene glycol) 1000 mass ppm), and electroless plating was performed at 45 ° C. and pH 11.5 for 10 minutes.
In the step (C), an etching solution containing 50 g / l sodium persulfate and 20 ml / l sulfuric acid was used for etching treatment at room temperature for 5 seconds. After the etching process, running water was washed for 30 seconds and dried using an air gun.
In step (D), instead of an electric nickel bath, an electrolytic copper bath (copper sulfate 200 g / l, sulfuric acid 50 g / l, SPS (bis (3-sulfopropyl disulfide)) 10 ppm, JGB (Janus Green B) 10 ppm, PEG -4000 (polyethylene glycol of molecular weight 4000) 100 ppm, hydrochloride ^- in (Cl as) 50 ppm), was carried out at room temperature, with stirring air PH0.01, 135 minutes electroplating at a current density of 1.0A / dm ^2.

<Comparative Examples 1 and 2>

  In Comparative Example 1, a three-dimensional metal structure was formed under the same conditions as in Example 1 except that the steps (B) and (C) were not performed. Moreover, the comparative example 2 formed the three-dimensional metal structure on the conditions similar to Example 2 except not performing the said (B) process and (C) process.

<Comparative Examples 3 and 4>
In the step (C), the same treatment as in Example 1 (Comparative Example 3) or Example 2 (Comparative Example 4) was performed except that the entire substrate was immersed in an etching solution (hereinafter also referred to as “normal immersion”). went.

<Evaluation>
The three-dimensional metal structures formed in Examples 1 and 2 and Comparative Examples 1 to 4 were observed using SEM. The results are shown in Table 1.

  As a result of observing the formed substrate, a conductive layer is formed by performing electroless plating in the step (B), and a part of the conductive layer is removed by inversion immersion, whereby a highly uniform three-dimensional metal structure on the substrate. It was found that a product can be formed (Examples 1 and 2). On the other hand, when the conductive layer by electroless plating is not formed (Comparative Examples 1 and 2), and when etching is performed by normal immersion instead of facing immersion (Comparative Examples 3 and 4), the formed three-dimensional It was found that the surface of the metal structure was not uniform.

It is a schematic diagram which shows the formation method of the three-dimensional metal structure by this invention. It is a schematic diagram which shows the formation method of the three-dimensional metal structure by a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Metal layer 3 Organic film 4 Organic film 5 Conductive layer 6 Etching solution 7 Concave part 8 Plating metal 9 Three-dimensional metal structure 11 Substrate 12 Metal layer 13 Negative photoresist resin layer 14 Negative photoresist resin layer 15 Conductive layer 16 Concave part 17 Plated metal 18 Three-dimensional metal structure

Claims (6)

(A) forming a patterned organic film on a substrate;
(B) forming a conductive layer on the patterned organic film surface by electroless plating;
(C) Ri Na comprise the steps of removing a portion of the conductive layer by etching,
In the step (C), a part of the conductive layer is removed by bringing the conductive layer into contact with an etching solution so that the conductive layer is in contact with the etching solution . The step (A)
(A-1) forming and exposing an organic film on the substrate;
(A-2) including the step of forming the multilayer patterned organic film by developing the organic film at the same time after the organic film is stacked by repeating the process (A-1) two or more times in total. The method according to claim 1.   3. The method according to claim 2, wherein the exposure area of the exposure in the step (A-1) is such that the exposure area of the organic film far from the exposure light source is larger than the exposure area of the organic film close to the exposure light source.   The method according to claim 1, wherein the patterned organic film is formed of a negative photoresist composition.   The method of claim 4, wherein the negative photoresist composition is a chemically amplified negative photoresist composition. (A) forming a patterned organic film on a substrate;
(B) forming a conductive layer on the patterned organic film surface by electroless plating;
(C) removing a part of the conductive layer by an etching process;
(D) Ri name includes a step for peeling the plating process and the patterned organic film, and
In the step (C), a part of the conductive layer is removed by bringing the conductive layer into contact with an etchant so as to remove the conductive layer .

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