Photosensitive element, production method therefor, resist pattern production method, and conductive pattern production method

Abstract

A photosensitive element 10 comprising: a support film 12; a positive photosensitive resin film 14 that is disposed on the support film 12; and a protective film 16 that is disposed on the photosensitive resin film 14, wherein the average thickness of the photosensitive resin film 14 is 150 µm or greater. A production method for a photosensitive element 10, said method comprising: a step for forming a photosensitive resin film 14 having an average thickness of 150 µm or greater by applying a positive photosensitive resin composition onto a support film 12 and then drying the photosensitive resin composition; and a step for providing a protective film 16 on the photosensitive resin film 14.

Description

Photosensitive Element, Method for Producing the Same, Method for Producing a Resist Pattern, and Method for Producing a Conductor Pattern

[0001] The present disclosure relates to a photosensitive element, a method for producing the same, a method for producing a resist pattern, a method for producing a conductor pattern, and the like.

[0002] In the production of a wiring board or the like, a resist pattern is formed in order to obtain a desired conductor pattern (for example, a wiring pattern). For example, the resist pattern can be formed by disposing a photosensitive resin film on a substrate using a photosensitive element including the photosensitive resin film and then exposing and developing the photosensitive resin film. Such a photosensitive element can be stored with the photosensitive resin film sandwiched between two films (for example, a support film and a protective film) (see Patent Document 1 below).

[0003] Japanese Patent Application Laid-Open No. 2017-126023 Japanese Patent Application Laid-Open No. 2022-129979 Japanese Patent Application Laid-Open No. 2020-76871 Japanese Patent Application Laid-Open No. 2017-198919

[0004] For the photosensitive element, there may be a case where it is required to include a thick photosensitive resin film in order to obtain a thick conductor pattern. However, the photosensitive element including a thick photosensitive resin film has not been sufficiently studied and there is room for improvement.

[0005] One aspect of the present disclosure aims to provide a photosensitive element including a thick photosensitive resin film. Another aspect of the present disclosure aims to provide a method for producing such a photosensitive element. Another aspect of the present disclosure aims to provide a method for producing a resist pattern using such a photosensitive element. Another aspect of the present disclosure aims to provide a method for producing a conductor pattern using such a method for producing a resist pattern.

[0006] This disclosure relates to the following [1] to

[16] etc. [1] A photosensitive element comprising a first film, a positive-type photosensitive resin film disposed on the first film, and a second film disposed on the photosensitive resin film, wherein the average thickness of the photosensitive resin film is 150 μm or more. [2] The photosensitive element according to [1], wherein the average thickness of the photosensitive resin film is 150 to 300 μm. [3] The photosensitive element according to [1] or [2], wherein an acetate-based solvent is present in the photosensitive resin film. [4] The photosensitive element according to [1] or [2], wherein an alkylene glycol monoalkyl ether acetate is present in the photosensitive resin film. [5] The photosensitive element according to [1] or [2], wherein an organic solvent with a boiling point of less than 150°C is present in the photosensitive resin film. [6] The photosensitive element according to any one of [1] to [5], wherein the average thickness of the first film is greater than 50 μm. [7] A method for manufacturing a resist pattern, comprising in this order: an arrangement step of arranging the photosensitive resin film of a photosensitive element according to any one of [1] to [6] on the substrate, with one of the first film and the second film removed and the photosensitive resin film positioned on the substrate side relative to the other of the first film and the second film; an exposure step of exposing a part of the photosensitive resin film; and a developing step of removing at least a part of the exposed portion of the photosensitive resin film to form a resist pattern. [8] The method for manufacturing a resist pattern according to [7], further comprising a step of heating the photosensitive resin film with the other film removed between the arrangement step and the exposure step. [9] The method for manufacturing a resist pattern according to [7] or [8], further comprising a step of heating the photosensitive resin film between the exposure step and the developing step.

[10] A method for manufacturing a conductor pattern, comprising a step of forming a conductor pattern using the resist pattern obtained by the method for manufacturing a resist pattern according to any one of [7] to [9] as a mask.

[11] A method for producing a photosensitive element, comprising the steps of: applying a positive-type photosensitive resin composition onto a first film and then drying the photosensitive resin composition to form a photosensitive resin film with an average thickness of 150 μm or more; and arranging a second film on the photosensitive resin film.

[12] The method for producing a photosensitive element according to

[11] , wherein the average thickness of the photosensitive resin film is 150 to 300 μm.

[13] The method for producing a photosensitive element according to

[11] or

[12] , wherein the photosensitive resin composition contains an acetate-based solvent.

[14] The method for producing a photosensitive element according to

[11] or

[12] , wherein the photosensitive resin composition contains an alkylene glycol monoalkyl ether acetate.

[15] The method for producing a photosensitive element according to

[11] or

[12] , wherein the photosensitive resin composition contains an organic solvent with a boiling point of less than 150°C.

[16] A method for manufacturing a photosensitive element according to any one of

[11] to

[15] , wherein the average thickness of the first film is greater than 50 μm.

[0007] According to one aspect of this disclosure, a photosensitive element comprising a thick photosensitive resin film can be provided. According to another aspect of this disclosure, a method for manufacturing such a photosensitive element can be provided. According to another aspect of this disclosure, a method for manufacturing a resist pattern using such a photosensitive element can be provided. According to yet another aspect of this disclosure, a method for manufacturing a conductor pattern using such a resist pattern manufacturing method can be provided.

[0008] This is a schematic cross-sectional view showing an example of a photosensitive element. This is a schematic cross-sectional view showing an example of a resist pattern manufacturing method. This is a schematic cross-sectional view showing an example of a resist pattern manufacturing method. This is a schematic cross-sectional view showing an example of a conductor pattern manufacturing method.

[0009] The embodiments of this disclosure will be described in detail below. However, this disclosure is not limited to the embodiments described below.

[0010] In this specification, numerical ranges indicated using "~" represent a range that includes the numbers listed before and after "~" as the minimum and maximum values, respectively. "A or greater" in a numerical range means A and the range exceeding A. "A or less" in a numerical range means A and the range less than A. In numerical ranges described stepwise in this specification, the upper or lower limit of a numerical range in one step can be arbitrarily combined with the upper or lower limit of a numerical range in another step. In numerical ranges described in this specification, the upper or lower limit of that numerical range may be replaced with the values ​​shown in the experimental examples. "A or B" means that either A or B may be included, or both may be included. Unless otherwise specified, the materials exemplified in this specification may be used individually or in combination of two or more. The content of each component in a composition means the total amount of multiple substances present in the composition if multiple substances corresponding to each component exist in the composition, unless otherwise specified. The term "layer" includes not only structures formed across the entire surface when observed as a plan view, but also structures formed in only a portion of it. The term "process" includes not only independent processes, but also processes that cannot be clearly distinguished from others, as long as the intended function of the process is achieved. "(Meth)acrylic" means at least one of acrylic and its corresponding methacrylic. Unless otherwise specified, alkyl groups may be linear, branched, or cyclic.

[0011] The photosensitive element according to this embodiment comprises a first film, a positive-type photosensitive resin film disposed on the first film, and a second film disposed on the photosensitive resin film, wherein the average thickness of the photosensitive resin film is 150 μm or more.

[0012] The photosensitive element according to this embodiment makes it easy to obtain thick conductor patterns. The photosensitive element according to this embodiment can be used in the manufacture of resist patterns, in the manufacture of conductor patterns, and in the manufacture of wiring boards.

[0013] The photosensitive element according to this embodiment comprises a first film, a positive-type photosensitive resin film (photosensitive layer) disposed on the first film, and a second film disposed on the photosensitive resin film. That is, the photosensitive element according to this embodiment comprises the first film, the photosensitive resin film, and the second film in this order. The photosensitive element according to this embodiment also comprises a first film, a second film, and a photosensitive resin film disposed between the first film and the second film. The first film can come into contact with the photosensitive resin film. The second film can come into contact with the photosensitive resin film.

[0014] Examples of the first and second films include polyolefin films such as polyethylene (PE) film and polypropylene (PP) film; and polyester films such as polyethylene terephthalate (PET) film, polybutylene terephthalate (PBT) film, and polyethylene-2,6-naphthalate (PEN) film. The first and second films may be of the same type or of different types. The first film may be a polyethylene terephthalate film, and the second film may be a polypropylene film.

[0015] The average thickness of the first film may be 1 μm or more, 5 μm or more, 10 μm or more, 15 μm or more, 20 μm or more, 25 μm or more, 30 μm or more, 35 μm or more, 40 μm or more, 45 μm or more, or 50 μm or more, from the viewpoint of easily suppressing damage to the first film when peeling the first film from the photosensitive element. The average thickness of the first film may be greater than 50 μm, 55 μm or more, 60 μm or more, 65 μm or more, 70 μm or more, 75 μm or more, 80 μm or more, 85 μm or more, 90 μm or more, 95 μm or more, or 100 μm or more, from the viewpoint of easily improving the uniformity of the thickness of the photosensitive resin film (in-plane uniformity: the same applies below), or from the viewpoint of further easily suppressing damage to the first film when peeling the first film from the photosensitive element. The average thickness of the first film may be 300 μm or less, 250 μm or less, 200 μm or less, 180 μm or less, 150 μm or less, 120 μm or less, 110 μm or less, 100 μm or less, 95 μm or less, 90 μm or less, 85 μm or less, 80 μm or less, 75 μm or less, 70 μm or less, 65 μm or less, 60 μm or less, 55 μm or less, or 50 μm or less, from the viewpoint of making it easy to roll the photosensitive element or to reduce wear on the blade when cutting the photosensitive element. From these viewpoints, the average thickness of the first film may be 1 to 300 μm, 1 to 150 μm, 1 to 80 μm, 30 to 300 μm, 30 to 150 μm, 30 to 80 μm, more than 50 μm and 300 μm or less, or more than 50 μm and 150 μm or less. The average thickness of the first film can be measured using the measurement method described in the experimental example below.

[0016] According to the inventors' findings, while photosensitive resin films with an average thickness of about 120 μm exhibit high uniformity in thickness (see the reference example described later), photosensitive resin films with an average thickness of 150 μm or more may exhibit low uniformity in thickness. On the other hand, in the photosensitive element according to this embodiment, even if the average thickness of the photosensitive resin film is 150 μm or more, the average thickness of the first film is greater than 50 μm, as described above, making it easier to improve the uniformity of the thickness of the photosensitive resin film. It is presumed that the larger average thickness of the first film leads to less deformation of the first film when heat is applied, thus making it easier to improve the uniformity of the thickness of the photosensitive resin film. However, the factors are not limited to those described above.

[0017] The average thickness of the second film may be 1 μm or more, 5 μm or more, 10 μm or more, 15 μm or more, 20 μm or more, 25 μm or more, 30 μm or more, 35 μm or more, or 40 μm or more, from the viewpoint of easily suppressing damage to the second film when peeling the second film from the photosensitive element. The average thickness of the second film may be 300 μm or less, 250 μm or less, 200 μm or less, 150 μm or less, 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, or 40 μm or less, from the viewpoint of easily winding the photosensitive element into a roll or easily suppressing wear of the blade when cutting the photosensitive element. From these perspectives, the average thickness of the second film may be 1-300 μm, 1-150 μm, 1-60 μm, 10-300 μm, 10-150 μm, 10-60 μm, 30-300 μm, 30-150 μm, or 30-60 μm. The average thickness of the second film can be measured by the measurement method described in the experimental examples below.

[0018] The photosensitive resin film has positive-type photosensitivity. The photosensitive resin film is a film containing a positive-type photosensitive resin composition, and may be a film made of a positive-type photosensitive resin composition.

[0019] The photosensitive resin composition may contain a resin having an acid-dissociable group. The resin having an acid-dissociable group is not particularly limited as long as it is a resin that can be used in a positive-type photosensitive resin composition. Examples of resins having an acid-dissociable group include novolac resins having an acid-dissociable group, hydroxystyrene resins having an acid-dissociable group, and (meth)acrylic resins having an acid-dissociable group. The resin having an acid-dissociable group can be used alone or in combination of two or more.

[0020] Acid-dissociable groups can generate alkali-soluble groups (carboxyl groups, phenolic hydroxyl groups, etc.) through the action of acid. Examples of acid-dissociable groups include alkyl groups, alkoxyalkyl groups, alkoxycarbonyl groups, vinyloxyethyl groups, tetrahydropyranyl groups, tetrahydrofuranyl groups, and trialkylsilyl groups. Examples of alkyl groups include methyl groups, ethyl groups, propyl groups, isopropyl groups, n-butyl groups, isobutyl groups, tert-butyl groups, pentyl groups, isopentyl groups, neopentyl groups, cyclopentyl groups, and cyclohexyl groups. Examples of alkoxyalkyl groups include methoxyethyl groups, ethoxyethyl groups, n-propoxyethyl groups, isopropoxyethyl groups, n-butoxyethyl groups, isobutoxyethyl groups, tert-butoxyethyl groups, cyclohexyloxyethyl groups, methoxypropyl groups, ethoxypropyl groups, and 1-methoxy-1-methylmethoxyethyl groups. Examples of alkoxycarbonyl groups include tert-butoxycarbonyl group and tert-butoxycarbonylmethyl group. Examples of trialkylsilyl groups include trimethylsilyl group and tri-tert-butyldimethylsilyl group.

[0021] Resins having acid-dissociable groups may include resins described in the above-mentioned Patent Documents 2 to 4, etc. (for example, resins whose solubility in alkalis increases due to the action of acid).

[0022] The photosensitive resin composition may contain a photoacid generator. The photoacid generator comprises one or more compounds that generate acid upon exposure to light (e.g., ultraviolet light) and can function as a photosensitive agent in the photosensitive resin composition. The acid generated from the photoacid generator upon absorption of light can selectively increase the solubility in alkaline aqueous solutions in the light-irradiated portion of the photosensitive resin composition.

[0023] The photoacid generator is not particularly limited as long as it is a compound that generates acid directly or indirectly upon exposure to light. The compounds constituting the photoacid generator may be selected from compounds commonly used as photoacid generators. Examples of photoacid generators include onium salt compounds, halogen-containing triazine compounds, diazoketone compounds, sulfonic acid compounds, sulfonimide compounds, and diazomethane compounds. The photoacid generator can be used individually or in combination of two or more.

[0024] Examples of onium salt compounds include iodonium salt compounds such as diaryliodonium salts; sulfonium salt compounds such as triarylsulfonium salts; diazonium salt compounds such as aryldiazonium salts; phosphonium salt compounds; and pyridinium salt compounds.

[0025] Examples of halogen-containing triazine compounds include s-triazine derivatives such as phenyl-bis(trichloromethyl)-s-triazine, 4-methoxyphenyl-bis(trichloromethyl)-s-triazine, styryl-bis(trichloromethyl)-s-triazine, and naphthyl-bis(trichloromethyl)-s-triazine.

[0026] Examples of diazoketone compounds include 1,3-diketo-2-diazo compounds, diazobenzoquinone compounds, and diazonaphthoquinone compounds.

[0027] Examples of sulfonic acid compounds include benzoin p-toluenesulfonate, pyrogallol trifluoromethanesulfonate, o-nitrobenzyl trifluoromethanesulfonate, and o-nitrobenzyl p-toluenesulfonate.

[0028] Examples of sulfonimide compounds include N-(trifluoromethylsulfonyloxy)succinimide, N-(trifluoromethylsulfonyloxy)phthalimide, N-(trifluoromethylsulfonyloxy)diphenylmaleimide, N-(trifluoromethylsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(trifluoromethylsulfonyloxy)naphthalimide, N-(p-toluenesulfonyloxy)-1,8-naphthalimide, and N-(10-camphorsulfonyloxy)-1,8-naphthalimide.

[0029] Examples of diazomethane compounds include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, and bis(phenylsulfonyl)diazomethane.

[0030] The photoacid generator may include compounds described in the above-mentioned Patent Documents 2 to 4, etc. (for example, compounds that generate acid upon irradiation with active light or radiation).

[0031] The content of the photoacid generator may be within the following ranges per 100 parts by mass of the resin having an acid-dissociable group: The content of the photoacid generator may be 0.01 parts by mass or more, 0.05 parts by mass or more, 0.1 parts by mass or more, or 0.2 parts by mass or more. The content of the photoacid generator may be 1.0 part by mass or less, 0.9 parts by mass or less, 0.8 parts by mass or less, or 0.7 parts by mass or less. From these viewpoints, the content of the photoacid generator may be 0.01 to 1.0 parts by mass, 0.05 to 0.9 parts by mass, 0.1 to 0.8 parts by mass, or 0.2 to 0.7 parts by mass.

[0032] The photosensitive resin composition may contain an organic solvent. In the photosensitive element according to this embodiment, the organic solvent may be present within the photosensitive resin film. Examples of organic solvents include acetate solvents, ether solvents, ester solvents, alcohol solvents, sulfoxide solvents, formamide solvents, acetamide solvents, pyrrolidone solvents, aromatic hydrocarbon solvents, and the like. The organic solvent can be used individually or in combination of two or more.

[0033] The photosensitive resin composition may contain an acetate-based solvent, from the viewpoint of easily adjusting the content of organic solvents in the photosensitive resin film by drying the photosensitive resin composition. In the photosensitive element according to this embodiment, the acetate-based solvent may be present in the photosensitive resin film. Examples of acetate-based solvents include alkylene glycol monoalkyl ether acetate, dialkylene glycol alkyl ether acetate, alkoxyalkyl acetate (for example, alkoxybutyl acetate such as 3-methoxybutyl acetate (MBA)), 3-methoxy-3-methylbutyl acetate, propylene glycol diacetate, 1,3-butylene glycol diacetate, 1,4-butanediol diacetate, 1,6-hexanediol diacetate, cyclohexanol acetate, and butyl acetate. Examples of alkylene glycol monoalkyl ether acetates include propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, and other propylene glycol monoalkyl ether acetates; and ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, and ethylene glycol monobutyl ether acetate. Examples of dialkylene glycol alkyl ether acetates include dipropylene glycol monoalkyl ether acetates such as dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, and dipropylene glycol monobutyl ether acetate; and diethylene glycol monoalkyl ether acetates such as diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, and diethylene glycol monobutyl ether acetate.

[0034] The photosensitive resin composition may contain at least one selected from the group consisting of alkylene glycol monoalkyl ether acetate and alkoxyalkyl acetate, and may also contain at least one selected from the group consisting of propylene glycol monomethyl ether acetate and 3-methoxybutyl acetate, from the viewpoint of easily adjusting the content of organic solvents in the photosensitive resin film by drying the photosensitive resin composition. The photosensitive resin composition may contain alkylene glycol monoalkyl ether acetate and may also contain propylene glycol monomethyl ether acetate, from the viewpoint of easily improving the uniformity of the thickness of the photosensitive resin film. It is presumed that by using alkylene glycol monoalkyl ether acetate, the boiling point of the entire solvent contained in the photosensitive resin film tends to decrease, and therefore the drying temperature can be lowered. Therefore, it is presumed that the amount of deformation of the first film when heat is applied tends to be reduced, and thus the uniformity of the thickness of the photosensitive resin film tends to be improved. However, the factors are not limited to the above.

[0035] In the photosensitive element according to this embodiment, from the viewpoint of easily adjusting the content of organic solvents in the photosensitive resin film, at least one selected from the group consisting of alkylene glycol monoalkyl ether acetate and alkoxyalkyl acetate may be present in the photosensitive resin film, and at least one selected from the group consisting of propylene glycol monomethyl ether acetate and 3-methoxybutyl acetate may be present in the photosensitive resin film. In the photosensitive element according to this embodiment, from the viewpoint of easily adjusting the content of organic solvents in the photosensitive resin film, alkylene glycol monoalkyl ether acetate may be present in the photosensitive resin film, and propylene glycol monomethyl ether acetate may be present in the photosensitive resin film.

[0036] The photosensitive resin composition may contain an organic solvent having a boiling point (boiling point at atmospheric pressure) within the following range (for example, an organic solvent with a boiling point of less than 150°C), from the viewpoint of easily adjusting the content of the organic solvent in the photosensitive resin film by drying the photosensitive resin composition. In the photosensitive element according to this embodiment, an organic solvent having a boiling point (boiling point at atmospheric pressure) within the following range (for example, an organic solvent with a boiling point of less than 150°C) may be present in the photosensitive resin film, from the viewpoint of easily adjusting the content of the organic solvent in the photosensitive resin film. The boiling point of the organic solvent may be 100°C or higher, 110°C or higher, 120°C or higher, 130°C or higher, 140°C or higher, 150°C or higher, 160°C or higher, or 170°C or higher. The boiling point of the organic solvent may be 200°C or lower, 190°C or lower, 180°C or lower, 170°C or lower, 160°C or lower, 150°C or lower, less than 150°C, 149°C or lower, 148°C or lower, 147°C or lower, or 146°C or lower. From these viewpoints, the boiling point of the organic solvent may be 100-200°C, 100-180°C, 100-160°C, 100°C or higher and less than 150°C, 130-200°C, 130-180°C, 130-160°C, 130°C or higher and less than 150°C, 140-200°C, 140-180°C, 140-160°C, 140°C or higher and less than 150°C, 150-200°C, or 150-180°C.

[0037] The content of organic solvents with a boiling point (boiling point at atmospheric pressure) of less than 150°C may be 50.0% by mass or more, more than 50.0% by mass, 60.0% by mass or more, 70.0% by mass or more, 80.0% by mass or more, 90.0% by mass or more, 93.0% by mass or more, 95.0% by mass or more, 98.0% by mass or more, 99.0% by mass or more, 99.5% by mass or more, or 99.9% by mass or more, based on the total mass of organic solvents contained in the photosensitive resin composition or the total mass of organic solvents present in the photosensitive resin film. The organic solvents contained in the photosensitive resin composition or the organic solvents present in the photosensitive resin film may be substantially composed of organic solvents with a boiling point of less than 150°C (a configuration in which substantially 100% by mass of the organic solvents contained in the photosensitive resin composition or the organic solvents present in the photosensitive resin film are organic solvents with a boiling point of less than 150°C). From a similar viewpoint, the group of compounds included in organic solvents with a boiling point (boiling point at atmospheric pressure) of less than 150°C, or the content of such compounds (for example, the content of alkylene glycol monoalkyl ether acetate, alkoxyalkyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, etc.) may also be within the ranges described above. The type and content of organic solvents present in the photosensitive resin film can be confirmed by gas chromatography.

[0038] The content of organic solvents with a boiling point (boiling point at atmospheric pressure) of less than 150°C may be within the following ranges based on the total mass of the photosensitive resin film: The content of organic solvents may be 1% by mass or more, 3% by mass or more, 5% by mass or more, 8% by mass or more, 10% by mass or more, 12% by mass or more, 14% by mass or more, 15% by mass or more, 16% by mass or more, or 17% by mass or more. The content of organic solvents may be 50% by mass or less, 40% by mass or less, 35% by mass or less, 30% by mass or less, 25% by mass or less, 23% by mass or less, 20% by mass or less, 18% by mass or less, 17% by mass or less, or 16% by mass or less. The content of the organic solvent may be 1-50% by mass, 1-30% by mass, 1-20% by mass, 10-50% by mass, 10-30% by mass, 10-20% by mass, 15-50% by mass, 15-30% by mass, or 15-20% by mass. From a similar viewpoint, the content of compounds included in organic solvents with a boiling point (boiling point at atmospheric pressure) of less than 150°C, or the content of compounds (for example, the content of alkylene glycol monoalkyl ether acetate, alkoxyalkyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, etc.) may also be within the above ranges. The content of the organic solvent in the photosensitive resin film can be confirmed by gas chromatography.

[0039] The average thickness of the photosensitive resin film is 150 μm or more, from the viewpoint of easily obtaining a thick conductor pattern. The average thickness of the photosensitive resin film may be 160 μm or more, 170 μm or more, or 180 μm or more. The average thickness of the photosensitive resin film may be 300 μm or less, 280 μm or less, 250 μm or less, 220 μm or less, 200 μm or less, 195 μm or less, 190 μm or less, or 185 μm or less. From these viewpoints, the average thickness of the photosensitive resin film may be 150 to 300 μm, 150 to 250 μm, 150 to 200 μm, 180 to 300 μm, 180 to 250 μm, or 180 to 200 μm. The average thickness of the photosensitive resin film can be measured by the measurement method in the experimental example described later.

[0040] The photosensitive element according to this embodiment may include a support layer (support film), a protective layer (protective film), a cushioning layer, an adhesive layer, a light-absorbing layer, a gas barrier layer, and the like. The photosensitive element according to this embodiment may be configured such that the first film is a support layer (support film) and the second film is a protective layer (protective film). The photosensitive element according to this embodiment may include the above-mentioned layers as films other than the first film and the second film.

[0041] Figure 1 is a schematic cross-sectional view showing an example of a photosensitive element. The photosensitive element 10 in Figure 1 comprises a support film (first film) 12, a positive-type photosensitive resin film 14 placed on the support film 12, and a protective film (second film) 16 placed on the photosensitive resin film 14, the average thickness of the photosensitive resin film 14 being 150 μm or more. The support film 12 and the protective film 16 are in contact with the photosensitive resin film 14. That is, the photosensitive element 10 comprises a photosensitive resin film 14, a support film 12 in contact with one side of the photosensitive resin film 14, and a protective film 16 in contact with the other side of the photosensitive resin film 14.

[0042] The method for manufacturing a photosensitive element according to this embodiment is a method for obtaining a photosensitive element according to this embodiment. The method for manufacturing a photosensitive element according to this embodiment comprises the steps of forming a photosensitive resin film with an average thickness of 150 μm or more by coating a positive-type photosensitive resin composition onto a first film and then drying the photosensitive resin composition, and placing a second film on the photosensitive resin film. At least a portion of the organic solvent can be removed by drying the photosensitive resin composition. According to the method for manufacturing a photosensitive element according to this embodiment, a photosensitive element according to this embodiment can be obtained.

[0043] From the perspective of reducing the drying time, the drying temperature of the photosensitive resin composition may be 70°C or higher, 80°C or higher, 90°C or higher, or 100°C or higher. From the perspective of easily adjusting the content of the organic solvent in the photosensitive resin film, the drying temperature of the photosensitive resin composition may be 150°C or lower, 140°C or lower, 130°C or lower, 120°C or lower, or 110°C or lower. From these perspectives, the drying temperature of the photosensitive resin composition may be 70 to 150°C, 80 to 140°C, 80 to 120°C, 90 to 130°C, 100 to 120°C, or 100 to 110°C.

[0044] From the perspective of excellent storage stability of the photosensitive resin film, the drying time of the photosensitive resin composition may be 6 minutes or longer, 10 minutes or longer, 12 minutes or longer, or 14 minutes or longer. From the perspective of excellent handling properties of the photosensitive resin film, the drying time of the photosensitive resin composition may be 80 minutes or shorter, 70 minutes or shorter, 60 minutes or shorter, 55 minutes or shorter, or 50 minutes or shorter. From these perspectives, the drying time of the photosensitive resin composition may be 6 to 80 minutes, 8 to 70 minutes, 10 to 60 minutes, 12 to 55 minutes, or 14 to 50 minutes. The drying time of the photosensitive resin composition can be adjusted according to the drying temperature.

[0045] The method for manufacturing a resist pattern according to this embodiment includes an arrangement step of arranging the photosensitive resin film of the photosensitive element according to this embodiment on a substrate in a state where one of the first film and the second film is removed and the photosensitive resin film is located on the substrate side with respect to the other of the first film and the second film, an exposure step of exposing a part of the photosensitive resin film, and a development step of removing at least a part (part or all) of the exposed part of the photosensitive resin film to form a resist pattern, in this order.

[0046] In the arrangement step, one of the first film and the second film (hereinafter referred to as "film F1") is removed, and the photosensitive resin film of the photosensitive element according to this embodiment is arranged on the substrate in a state where the photosensitive resin film is located on the substrate side with respect to the other of the first film and the second film (hereinafter referred to as "film F2").

[0047] In the placement step, the photosensitive resin film can be placed on the substrate with the photosensitive resin film in contact with the substrate. When placing the photosensitive resin film on the substrate, the photosensitive resin film may be pressure-bonded to the substrate while heating the photosensitive resin film. The heating temperature during pressure bonding may be, for example, 70 to 130 °C, and the pressure during pressure bonding may be, for example, 0.1 to 1.0 MPa (1 to 10 kgf / cm ２ ), but these conditions can be appropriately selected as needed. The placement step may be performed under reduced pressure.

[0048] The substrate may include a conductor layer, and may include an insulating layer and a conductor layer disposed on the insulating layer. The substrate is not particularly limited, and examples include a circuit forming substrate including an insulating layer and a conductor layer disposed on the insulating layer; a die pad (substrate for lead frame) such as an alloy substrate; a silicon substrate; a glass substrate, and the like.

[0049] In the exposure step, a part of the photosensitive resin film is exposed. In the exposure step, the photosensitive resin film can be exposed by actinic rays. In the exposure step, the photosensitive resin film may be exposed in a state where the film F2 is removed, or the photosensitive resin film may be exposed by actinic rays through the film F2.

[0050] As the exposure method, a known exposure method can be used without particular limitation, and examples include a method of irradiating actinic rays in an image shape through a positive mask pattern called an artwork (mask exposure method), an LDI (Laser Direct Imaging) exposure method, a method of irradiating in an image shape through a lens using actinic rays obtained by projecting an image of a photomask (projection exposure method), and the like.

[0051] As the light source of the actinic rays, a known light source can be used without particular limitation, and a light source that emits ultraviolet rays can be used. Examples of the light source that emits ultraviolet rays include a carbon arc lamp, a mercury vapor arc lamp, a high-pressure mercury lamp, a xenon lamp, a gas laser (argon laser, etc.), a solid laser (YAG laser, etc.), a semiconductor laser (gallium nitride-based blue-violet laser, etc.), and the like. [[ID=1?]]

[0052] In the development process, at least a portion of the exposed area of ​​the photosensitive resin film is removed to form a resist pattern. If film F2 is placed on the photosensitive resin film during the exposure process, the development process may be performed after removing film F2. The development method may be wet development or dry development.

[0053] In the case of wet development, the photosensitive resin film can be developed using a developer solution appropriate to its composition and a known wet development method. Examples of wet development methods include the dip method, paddle method, high-pressure spray method, brushing, scrubbing, and agitation immersion method. One wet development method may be used alone or in combination of two or more methods.

[0054] The developer can be appropriately selected depending on the composition of the photosensitive resin film. Examples of developers include alkaline aqueous solutions and organic solvent developers.

[0055] Examples of bases in alkaline aqueous solutions include alkali hydroxides such as lithium, sodium, or potassium hydroxides; alkali carbonates such as lithium, sodium, potassium, or ammonium carbonates or bicarbonates; alkali metal phosphates such as potassium phosphate and sodium phosphate; alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate; sodium borate; sodium metasilicate; tetramethylammonium hydroxide; ethanolamine; ethylenediamine; diethylenetriamine; 2-amino-2-hydroxymethyl-1,3-propanediol; 1,3-diamino-2-propanol; and morpholine.

[0056] Examples of organic solvents used in organic solvent developers include 1,1,1-trichloroethane, N-methyl-2-pyrrolidone, N,N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone.

[0057] The method for manufacturing a resist pattern according to this embodiment may include a step of obtaining a photosensitive element by the method for manufacturing a photosensitive element according to this embodiment, prior to the arrangement step.

[0058] The resist pattern manufacturing method according to this embodiment may include a step of removing (peeling off) the film F1 from the photosensitive element before the placement step. The resist pattern manufacturing method according to this embodiment may include a step of removing (peeling off) the film F2 from the photosensitive element between the placement step and the exposure step, or between the exposure step and the development step.

[0059] The method for manufacturing a resist pattern according to this embodiment may include a heating step (hereinafter referred to as the "first heating step") between the arrangement step and the exposure step, in order to reduce the residual solvent in the photosensitive resin film, and may also include a step of heating the photosensitive resin film while the film F2 has been removed.

[0060] The heating temperature in the first heating step may be 50°C or higher, 60°C or higher, 70°C or higher, 80°C or higher, 90°C or higher, or 100°C or higher. The heating temperature may be 200°C or lower, 190°C or lower, 180°C or lower, 170°C or lower, 160°C or lower, or 150°C or lower. From these viewpoints, the heating temperature may be 50 to 200°C, 60 to 180°C, or 80 to 160°C. The first heating step may have multiple steps with different heating temperatures.

[0061] The method for manufacturing a resist pattern according to this embodiment may include a heating step (hereinafter referred to as the "second heating step") between the exposure step and the development step, in order to improve adhesion to the substrate.

[0062] The heating temperature in the second heating step may be 50°C or higher, 60°C or higher, 70°C or higher, 80°C or higher, 90°C or higher, or 100°C or higher. The heating temperature may be 250°C or lower, 230°C or lower, 210°C or lower, 200°C or lower, 190°C or lower, or 180°C or lower. From these viewpoints, the heating temperature may be 50 to 250°C, 60 to 200°C, or 80 to 180°C. The second heating step may have multiple steps with different heating temperatures.

[0063] The method for manufacturing a resist pattern according to this embodiment may include a step of heating or exposing the resist pattern after the development step.

[0064] Figures 2 and 3 are schematic cross-sectional views showing an example of a resist pattern manufacturing method, and are schematic cross-sectional views showing an example of a resist pattern manufacturing method using a positive-type photosensitive photosensitive resin film. In Figure 2(a), a substrate 20 is prepared. The substrate 20 comprises an insulating layer 22 and a conductive layer 24 disposed on the insulating layer 22. The conductive layer 24 is, for example, a copper layer. In Figure 2(b), after removing the protective film 16 of the photosensitive element 10 in Figure 1, the photosensitive resin film 14 and support film 12 of the photosensitive element 10 are laminated on the substrate 20. In Figure 2(c), after removing the support film 12, the photosensitive resin film 14 is heated. In Figure 3(a), an exposed area 14a is formed on the photosensitive resin film 14 by irradiating the photosensitive resin film 14 with an active light L onto which the image of the photomask is projected (exposure by projection exposure method). In Figure 3(b), a resist pattern 14b is formed on the substrate 20 by removing the exposed portion 14a of the photosensitive resin film 14 from the substrate 20.

[0065] The method for manufacturing a conductor pattern according to this embodiment includes a step of forming a conductor pattern using a resist pattern obtained by the resist pattern manufacturing method according to this embodiment as a mask. In the method for manufacturing a conductor pattern according to this embodiment, the conductor pattern may be formed by performing a plating treatment or etching treatment using the resist pattern obtained by the resist pattern manufacturing method according to this embodiment as a mask, or the conductor pattern may be formed by performing a plating treatment or etching treatment on a substrate on which the resist pattern obtained by the resist pattern manufacturing method according to this embodiment has been formed. Examples of constituent materials for the conductor pattern include copper, solder, nickel, and gold.

[0066] In the method for manufacturing a conductor pattern according to the first embodiment, a resist pattern obtained by the resist pattern manufacturing method according to this embodiment is used as a mask, and a conductor pattern is formed by applying a plating treatment to at least a part (or all) of the portion of the substrate where the resist pattern is not formed. In the method for manufacturing a conductor pattern according to the first embodiment, the substrate has a conductor layer, and the resist pattern obtained by the resist pattern manufacturing method according to this embodiment is formed on the conductor layer. The resist pattern is used as a mask, and a conductor pattern is formed by applying a plating treatment to at least a part (or all) of the portion of the substrate's conductor layer where the resist pattern is not formed. The materials of the substrate's conductor layer and the plating layer (conductor layer) formed by the plating treatment may be the same or different. If the materials of the substrate's conductor layer and the plating layer (conductor layer) formed by the plating treatment are the same, the conductor layer and the plating layer may be integrated. The plating treatment may be electrolytic plating or electroless plating. Examples of plating treatments include copper plating, solder plating, nickel plating, gold plating, etc.

[0067] In the method for manufacturing a conductor pattern according to the second embodiment, the substrate comprises a conductor layer, and a resist pattern obtained by the method for manufacturing a resist pattern according to this embodiment is formed on the conductor layer. Using the resist pattern as a mask, a conductor pattern covered by the resist pattern is formed by etching away at least a portion (part or all) of the conductor layer not covered by the resist pattern. The etching method is appropriately selected according to the conductor layer to be removed.

[0068] The method for manufacturing a conductor pattern according to this embodiment may include a step of removing the resist pattern on the substrate after plating or etching. The resist pattern can be removed, for example, with an aqueous solution that is more strongly alkaline than the alkaline aqueous solution used in the developing step.

[0069] In the method for manufacturing a conductor pattern according to the first embodiment, if the substrate has a conductor layer, after removing the resist pattern, the portion of the conductor layer of the substrate that was covered by the resist pattern may be removed by etching (for example, flash etching). The etching method is appropriately selected depending on the conductor layer to be removed.

[0070] One embodiment of the method for manufacturing a conductor pattern according to this embodiment is a method for manufacturing a wiring substrate (for example, a method for manufacturing a printed circuit board), and the method for manufacturing a wiring substrate according to this embodiment includes a step of forming a wiring pattern (for example, a circuit) as a conductor pattern using a resist pattern obtained by the method for manufacturing a resist pattern according to this embodiment as a mask. The wiring substrate according to this embodiment can be obtained by the method for manufacturing a wiring substrate according to this embodiment. The wiring substrate according to this embodiment may be a single-layer printed circuit board, a multilayer printed circuit board, or a printed circuit board having small-diameter through-holes.

[0071] Figure 4 is a schematic cross-sectional view showing an example of a method for manufacturing a conductor pattern, and is a schematic cross-sectional view showing an example of a method for manufacturing a conductor pattern using the resist pattern 14b in Figure 3. In Figure 4(a), a plating layer 30 is formed on the conductor layer 24 that is not covered by the resist pattern 14b on the substrate 20 by a plating process using the resist pattern 14b as a mask. In Figure 4(b), after removing the resist pattern 14b, a conductor layer 24a is formed by removing the portion of the conductor layer 24 that was covered by the resist pattern 14b. As a result, a conductor pattern 40 composed of the conductor layer 24a and the plating layer 30 is formed.

[0072] The following experimental examples will provide a more detailed explanation of this disclosure, but this disclosure is not limited to the following experimental examples.

[0073] <Preparation of Photosensitive Element> (Experimental Example 1) A polyethylene terephthalate film with an average thickness of 50 μm (manufactured by Toyobo Co., Ltd., product name "A-5300", width: 590 mm) was prepared as a support film. Next, a positive-type photosensitive resin composition (non-volatile content: 50% by mass) containing propylene glycol monomethyl ether acetate (PGMEA) as an organic solvent was prepared using "PMER P-BZ4000" manufactured by Tokyo Ohka Kogyo Co., Ltd. After applying this positive-type photosensitive resin composition onto the support film in a direction perpendicular to the width direction of the support film, a photosensitive resin film (average thickness after drying: 180 μm) was formed by drying it at 100°C for 40 minutes using a hot air convection dryer. Subsequently, a biaxially oriented polypropylene film with an average thickness of 40 μm (manufactured by Oji F-Tex Co., Ltd., product name "MA-420") was laminated to the photosensitive resin film as a protective film to obtain laminate A. Then, with the protective film positioned vertically above the photosensitive resin film, a photosensitive element was fabricated by applying pressure to laminate A using a roll laminating machine (manufactured by MCK Corporation, product name "MRK-650Y") at a temperature of 70°C (upper and lower rolls), a roll speed of 1.3 m / min, and a pressure of 0.5 MPa, thereby laminating the support film, photosensitive resin film, and protective film in that order.

[0074] (Experimental Example 2) A photosensitive element was fabricated in the same manner as in Experimental Example 1, except that the support film was changed to a polyethylene terephthalate film with an average thickness of 100 μm (manufactured by Toyobo Co., Ltd., product name "TN200", width: 590 mm).

[0075] (Experimental Example 3) A photosensitive element was prepared in the same manner as in Experimental Example 1, except that a positive-type photosensitive resin composition (non-volatile content: 50% by mass) containing 3-methoxybutyl acetate (MBA) as an organic solvent was prepared using the product name "PMER P-BZ4000" manufactured by Tokyo Ohka Kogyo Co., Ltd.

[0076] (Reference Example) A photosensitive element was fabricated in the same manner as in Experimental Example 3, except that the average thickness of the photosensitive resin film after drying was changed to 120 μm.

[0077] <Measurement of Residual Solvent> Calibration curves for propylene glycol monomethyl ether acetate and 3-methoxybutyl acetate were prepared by gas chromatography under the following conditions. Next, after removing the support film and protective film from the photosensitive element, the photosensitive resin film was dissolved in acetone, and the residual solvent in the photosensitive resin film was measured by gas chromatography. The presence of propylene glycol monomethyl ether acetate in the photosensitive resin film was confirmed in Experimental Examples 1 and 2. The content of propylene glycol monomethyl ether acetate relative to the total mass of the photosensitive resin film was 16.1% by mass in Experimental Example 1 and 15.4% by mass in Experimental Example 2. The presence of 3-methoxybutyl acetate in the photosensitive resin film was confirmed in Experimental Example 3. The content of 3-methoxybutyl acetate relative to the total mass of the photosensitive resin film was 17.2% by mass in Experimental Example 3. Measurement device: Agilent Technologies GC 7890B Carrier gas: Nitrogen gas, 5.0 mL / min Column: DB-WAX Polyethylene Glycol (0.53 mm I.D. × 30 m, 1.0 μm) Oven temperature: Heat at 60°C for 5 min, then increase to 200°C at 20°C / min Detector: FID

[0078] <Measurement of Average Thickness> The average thickness of the support film, photosensitive resin film, and protective film was measured using the following procedure. First, a test piece measuring 50 mm in length and 320 mm in width (horizontal direction = width direction of the support film) was obtained by cutting the photosensitive element. Marks were made on the surface of the support film and protective film at the center of this test piece, at two positions located 60 mm apart from the center in the horizontal direction, and at two positions located 120 mm apart from the center in the horizontal direction. The average thickness of the photosensitive element was obtained by measuring the thickness of these five positions (marked positions) on the photosensitive element using a contact-type film thickness gauge (manufactured by Mitutoyo Corporation, product name "VL-50"). After peeling off the protective film, the average thickness of the protective film was obtained by measuring the thickness of the five positions (marked positions) on the protective film using the same contact-type film thickness gauge. After peeling off the support film, the average thickness of the support film was obtained by measuring the thickness of the five positions (marked positions) on the support film using the same contact-type film thickness gauge. The average thickness of the photosensitive resin film was obtained by subtracting the average thickness of the protective film and the average thickness of the support film from the average thickness of the photosensitive elements.

[0079] <Uniformity of Thickness of Photosensitive Resin Film> The thickness of the photosensitive resin film at the photosensitive element was measured every 10 mm along the width direction of the support film using a contact-type film thickness gauge (Mitutoyo Corporation, product name "VL-50"). The thickness of the photosensitive resin film was obtained by subtracting the average thickness of the protective film and the average thickness of the support film from the thickness of the photosensitive element. For a position (30 mm) at one end of the photosensitive resin film in the width direction of the support film, the difference A between the thickness of the photosensitive resin film and the average thickness of the photosensitive resin film was calculated. If the difference A was 10 μm or less, it was judged as "A", if the difference A was more than 10 μm and 30 μm or less, it was judged as "B", and if the difference A was more than 30 μm, it was judged as "C". The results are shown in Table 1. For the central part of the photosensitive resin film in the width direction of the support film (the central 240 mm area), the difference B between the maximum and minimum thickness of the photosensitive resin film was calculated. A difference of B of 10 μm or less was classified as "A", a difference of B greater than 10 μm and 20 μm or less was classified as "B", and a difference of B greater than 20 μm was classified as "C". The results are shown in Table 1.

[0080]

[0081] 10...Photosensitive element, 12...Support film, 14...Photosensitive resin film, 14a...Exposure area, 14b...Resist pattern, 16...Protective film, 20...Substrate, 22...Insulating layer, 24, 24a...Conducting layer, 30...Plating layer, 40...Conducting pattern, L...Activating light.

Claims

1. A photosensitive element comprising a first film, a positive-type photosensitive resin film disposed on the first film, and a second film disposed on the photosensitive resin film, wherein the average thickness of the photosensitive resin film is 150 μm or more.

2. The photosensitive element according to claim 1, wherein the average thickness of the photosensitive resin film is 150 to 300 μm.

3. The photosensitive element according to claim 1, wherein an acetate-based solvent is present within the photosensitive resin film.

4. The photosensitive element according to claim 1, wherein an alkylene glycol monoalkyl ether acetate is present in the photosensitive resin film.

5. The photosensitive element according to claim 1, wherein an organic solvent with a boiling point of less than 150°C is present in the photosensitive resin film.

6. The photosensitive element according to claim 1, wherein the average thickness of the first film is greater than 50 μm.

7. A method for manufacturing a resist pattern, comprising, in this order: an arrangement step of arranging the photosensitive resin film of the photosensitive element according to any one of claims 1 to 6 on the substrate, with one of the first film and the second film removed and the photosensitive resin film positioned on the substrate side relative to the other of the first film and the second film; an exposure step of exposing a part of the photosensitive resin film; and a developing step of removing at least a part of the exposed portion of the photosensitive resin film to form a resist pattern.

8. The method for manufacturing a resist pattern according to claim 7, further comprising the step of heating the photosensitive resin film with the other film removed between the arrangement step and the exposure step.

9. The method for manufacturing a resist pattern according to claim 7, further comprising a step of heating the photosensitive resin film between the exposure step and the development step.

10. A method for manufacturing a conductor pattern, comprising the step of forming a conductor pattern using a resist pattern obtained by the method for manufacturing a resist pattern described in claim 7 as a mask.

11. A method for manufacturing a photosensitive element, comprising the steps of: forming a photosensitive resin film with an average thickness of 150 μm or more by applying a positive-type photosensitive resin composition onto a first film and then drying the photosensitive resin composition; and arranging a second film on the photosensitive resin film.

12. The method for manufacturing a photosensitive element according to claim 11, wherein the average thickness of the photosensitive resin film is 150 to 300 μm.

13. The method for producing a photosensitive element according to claim 11, wherein the photosensitive resin composition contains an acetate-based solvent.

14. The method for producing a photosensitive element according to claim 11, wherein the photosensitive resin composition contains alkylene glycol monoalkyl ether acetate.

15. The method for producing a photosensitive element according to claim 11, wherein the photosensitive resin composition contains an organic solvent with a boiling point of less than 150°C.

16. A method for manufacturing a photosensitive element according to any one of claims 11 to 15, wherein the average thickness of the first film is greater than 50 μm.

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