Photosensitive element, method for manufacturing the same, method for manufacturing resist pattern, and method for manufacturing conductor pattern

Abstract

A photosensitive element (10) includes a support film (12), a positive photosensitive resin film (14) disposed on the support film (12), and a protective film (16) disposed on the photosensitive resin film (14), the photosensitive resin film (14) having an average thickness of 150 μm or more. A method for manufacturing a photosensitive element (10) includes a step of forming a photosensitive resin film (14) having an average thickness of 150 μm or more by drying a positive photosensitive resin composition after applying the positive photosensitive resin composition on a support film (12), and a step of disposing a protective film (16) on the photosensitive resin film (14).

Description

Technical Field

[0001] This invention relates to a photosensitive element and its manufacturing method, a method for manufacturing resist patterns, a method for manufacturing conductor patterns, etc. Background Technology

[0002] In the manufacture of circuit boards and the like, a resist pattern is formed to obtain a desired conductor pattern (e.g., a circuit pattern). For example, the resist pattern can be formed by placing a photosensitive resin film on a substrate using a photosensitive element having a photosensitive resin film, followed by exposure and development of the photosensitive resin film. This photosensitive element can be stored with the photosensitive resin film sandwiched between two films (e.g., a support film and a protective film) (see Patent Document 1 below).

[0003] Previous technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2017-126023

[0006] Patent Document 2: Japanese Patent Application Publication No. 2022-129979

[0007] Patent Document 3: Japanese Patent Application Publication No. 2020-76871

[0008] Patent Document 4: Japanese Patent Application Publication No. 2017-198919 Summary of the Invention

[0009] The technical problem to be solved by the invention

[0010] For photosensitive elements, a thick photosensitive resin film is sometimes required to obtain a thick conductor pattern. However, photosensitive elements with thick photosensitive resin films have not been fully explored, and there is still room for improvement.

[0011] One object of the present invention is to provide a photosensitive element having a thick photosensitive resin film. Another object of the present invention is to provide a method for manufacturing such a photosensitive element. Another object of the present invention is to provide a method for manufacturing a resist pattern using such a photosensitive element. Another object of the present invention is to provide a method for manufacturing a conductor pattern using this resist pattern manufacturing method.

[0012] means for solving technical problems

[0013] This invention relates to the following [1] to

[16] etc.

[0014] [1] A photosensitive element comprising: a first film, a positive 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.

[0015] [2] According to the photosensitive element described in [1], the average thickness of the photosensitive resin film is 150 to 300 μm.

[0016] [3] According to the photosensitive element of [1] or [2], wherein an acetate solvent is present in the photosensitive resin film.

[0017] [4] According to the photosensitive element of [1] or [2], wherein an alkylene glycol monoalkyl ether acetate is present in the photosensitive resin film.

[0018] [5] According to the photosensitive element of [1] or [2], wherein an organic solvent with a boiling point of less than 150°C is present in the photosensitive resin film.

[0019] [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.

[0020] [7] A method for manufacturing a resist pattern, comprising: a placement step, wherein, in a state in which one of the first film and the second film is removed and the photosensitive resin film is located on the substrate side relative to the other of the first film and the second film, the photosensitive resin film of the photosensitive element described in any one of [1] to [6] is placed on the substrate; an exposure step, wherein a portion of the photosensitive resin film is exposed; and a developing step, wherein at least a portion of the exposed portion of the photosensitive resin film is removed to form a resist pattern.

[0021] [8] The method for manufacturing a resist pattern according to [7] further includes, between the configuration step and the exposure step, a step of heating the photosensitive resin film while the other film has been removed.

[0022] [9] The method for manufacturing a resist pattern according to [7] or [8] further includes a step of heating the photosensitive resin film between the exposure step and the development step.

[0023]

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

[0024]

[11] A method for manufacturing a photosensitive element, comprising: a step of forming a photosensitive resin film with an average thickness of 150 μm or more by coating a positive photosensitive resin composition onto a first film and then drying the photosensitive resin composition; and a step of disposing a second film onto the photosensitive resin film.

[0025]

[12] In the method for manufacturing a photosensitive element according to

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

[0026]

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

[11] or

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

[0027]

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

[11] or

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

[0028]

[15] The method for manufacturing 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.

[0029]

[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.

[0030] Invention Effects

[0031] According to one aspect of the present invention, a photosensitive element having a thick photosensitive resin film can be provided. According to another aspect of the present invention, a method for manufacturing such a photosensitive element can be provided. According to another aspect of the present invention, a method for manufacturing a resist pattern using such a photosensitive element can be provided. According to another aspect of the present invention, a method for manufacturing a conductor pattern using the method for manufacturing such a resist pattern can be provided. Attached Figure Description

[0032] Figure 1 This is a schematic cross-sectional view showing an example of a photosensitive element.

[0033] Figure 2 This is a schematic cross-sectional view illustrating an example of a method for manufacturing a resist pattern.

[0034] Figure 3 This is a schematic cross-sectional view illustrating an example of a method for manufacturing a resist pattern.

[0035] Figure 4 This is a schematic cross-sectional view illustrating an example of a method for manufacturing a conductor pattern. Detailed Implementation

[0036] The embodiments of the present invention will now be described in detail. However, the present invention is not limited to the following embodiments.

[0037] In this specification, the numerical range indicated by "~" represents the range encompassed by the values ​​recorded before and after "~" as the minimum and maximum values, respectively. "Above A" in a numerical range refers to the range of A and greater than A. "Below A" in a numerical range refers to the range of A and less than A. Within the numerical ranges described in stages in this specification, the upper or lower limit of a certain stage's numerical range can be arbitrarily combined with the upper or lower limits of other stages' numerical ranges. Within the numerical ranges described in this specification, the upper or lower limit of the numerical range can be replaced with the values ​​shown in the experimental examples. Regarding "A or B," either A or B is sufficient, or both may be included. Unless otherwise specified, the materials exemplified in this specification can be used alone or in combination of two or more. The content of each component in the composition refers to the total amount of the substances present in the composition when multiple substances equivalent to each component are present in the composition, unless otherwise specified. Regarding the term "layer," when viewed as a planar diagram, it includes not only structures forming shapes across the entire surface but also structures forming shapes locally. The term "process" includes not only independent processes, but also processes that cannot be clearly distinguished from others, as long as the desired effect of the process is achieved. "(Meth)acrylic acid" refers to at least one of acrylic acid and its corresponding methacrylic acid. Unless otherwise specified, alkyl groups can be linear, branched, or cyclic.

[0038] The photosensitive element according to this embodiment includes a first film, a positive 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.

[0039] According to the photosensitive element of this embodiment, thick conductor patterns can be easily obtained. The photosensitive element of this embodiment can be used for the manufacture of resist patterns, the manufacture of conductor patterns, and the manufacture of circuit boards.

[0040] The photosensitive element according to this embodiment includes a first film, a positive 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 sequentially includes a first film, a photosensitive resin film, and a second film. Furthermore, the photosensitive element according to this embodiment includes a first film, a second film, and a photosensitive resin film disposed between the first film and the second film. The first film can be in contact with the photosensitive resin film. The second film can be in contact with the photosensitive resin film.

[0041] 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-naphthalenedicarboxylate (PEN) film. The first and second films can be of the same or different types. For example, the first film can be a polyethylene terephthalate film, and the second film can be a polypropylene film.

[0042] From the viewpoint of easily suppressing damage to the first film when peeling it from the photosensitive element, the average thickness of the first film can 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 improving the uniformity of the thickness of the photosensitive resin film (in-plane uniformity: the same below) or more easily suppressing damage to the first film when peeling it from the photosensitive element, the average thickness of the first film can 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 rolling the photosensitive element into a roller or easily suppressing the wear of the cutting tool when cutting the photosensitive element, the average thickness of the first film can 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 these viewpoints, the average thickness of the first film can be 1–300 μm, 1–150 μm, 1–80 μm, 30–300 μm, 30–150 μm, 30–80 μm, greater than 50 μm and less than 300 μm, or greater than 50 μm and less than 150 μm. The average thickness of the first membrane can be determined by the measurement method described in the experimental examples below.

[0043] According to the inventors' understanding, while the uniformity of the thickness of a photosensitive resin film with an average thickness of about 120 μm is high (refer to the reference examples described later), the uniformity of the thickness of a photosensitive resin film with an average thickness of 150 μm or more can sometimes be low. 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, as described above, the uniformity of the thickness of the photosensitive resin film can be easily improved by having an average thickness of the first film greater than 50 μm. It is presumed that because the average thickness of the first film is large, the deformation of the first film during heating is small, and therefore the uniformity of the thickness of the photosensitive resin film is easily improved. However, the reasons are not limited to this.

[0044] From the viewpoint of easily suppressing damage to the second film when peeling it from the photosensitive element, the average thickness of the second film can 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 rolling the photosensitive element into a roller or easily suppressing the wear of the cutting tool when cutting the photosensitive element, the average thickness of the second film can 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. Based on these viewpoints, the average thickness of the second membrane can 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 membrane can be determined using the measurement methods described in the experimental examples below.

[0045] The photosensitive resin film has positive photosensitivity. The photosensitive resin film is a film containing a positive photosensitizing resin composition, or it can be a film formed from a positive photosensitizing resin composition.

[0046] The photosensitive resin composition may contain a resin having an acid-dissociable group. There are no particular limitations on the type of resin having an acid-dissociable group, as long as it is a resin suitable for use in a positive photosensitive resin composition. Examples of resins having an acid-dissociable group include phenolic varnish resins, hydroxystyrene resins, and (meth)acrylic resins. One or more resins having an acid-dissociable group can be used alone.

[0047] Acid-dissociable groups can generate base-soluble groups (carboxyl groups, phenolic hydroxyl groups, etc.) through the action of acids. Examples of acid-dissociable groups include alkyl, alkoxyalkyl, alkoxycarbonyl, ethyleneoxyethyl, tetrahydropyranyl, tetrahydrofuranyl, and trialkylsilyl. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, cyclopentyl, and cyclohexyl. Examples of alkoxyalkyl groups include methoxyethyl, ethoxyethyl, n-propoxyethyl, isopropoxyethyl, n-butoxyethyl, isobutoxyethyl, tert-butoxyethyl, cyclohexoxyethyl, methoxypropyl, ethoxypropyl, and 1-methoxy-1-methylmethoxyethyl. Examples of alkoxycarbonyl groups include tert-butoxycarbonyl and tert-butoxycarbonylmethyl. Examples of trialkylsilyl groups include trimethylsilyl and tri-tert-butyldimethylsilyl.

[0048] Resins having acid-dissociable groups may include the resins described in Patent Documents 2 to 4 above (e.g., resins whose solubility in alkali is increased by the action of acid).

[0049] 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 functions as a photosensitizer in the photosensitive resin composition. Through the action of the acid generated from the photoacid generator upon light absorption, the solubility in alkaline aqueous solutions can be selectively increased in the light-exposed portion of the photosensitive resin composition.

[0050] There are no particular limitations on the type of photoacid generator, as long as it is a compound that generates acid directly or indirectly through light. The compounds constituting the photoacid generator can be selected from those commonly used as photoacid generators. Examples of photoacid generators include onium salt compounds, halogenated triazine compounds, diazonium ketone compounds, sulfonic acid compounds, sulfonylimide compounds, and diazomethane compounds. Photoacid generators can be used alone or in combination of two or more.

[0051] 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 aryl diazonium salts; phosphonium salt compounds; and pyridinium salt compounds.

[0052] Examples of halogenated triazine compounds include phenyl-bis(trichloromethyl)-s-triazine, 4-methoxyphenyl-bis(trichloromethyl)-s-triazine, styryl-bis(trichloromethyl)-s-triazine, naphthyl-bis(trichloromethyl)-s-triazine, and other s-triazine derivatives.

[0053] Examples of diazonium ketone compounds include 1,3-dione-2-diazo compounds, diazonobenzoquinone compounds, and diazononaphthoquinone compounds.

[0054] Examples of sulfonic acid compounds include benzoin p-toluenesulfonate, pyrogallol trifluoromethanesulfonate, o-nitrobenzyl trifluoromethanesulfonate, and o-nitrobenzyl p-toluenesulfonate.

[0055] Examples of sulfonylimide compounds include N-(trifluoromethylsulfonyloxy)succinimide, N-(trifluoromethylsulfonyloxy)phthalimide, N-(trifluoromethylsulfonyloxy)diphenylmaleimide, N-(trifluoromethylsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid imide, N-(trifluoromethylsulfonyloxy)naphthalenedicarboximide, N-(p-toluenesulfonyloxy)-1,8-naphthalenedicarboximide, and N-(10-camphorsulfonyloxy)-1,8-naphthalenedicarboximide.

[0056] Examples of diazonium compounds include bis(trifluoromethanesulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, and bis(phenylsulfonyl)diazomethane.

[0057] Photoacid generators may include compounds described in Patent Documents 2 to 4 above (e.g., compounds that produce acid by irradiation with active light or radiation).

[0058] The content of the photoacid-generating agent relative to 100 parts by weight of the resin having acid-dissociating groups can be within the following ranges: The content of the photoacid-generating agent can be 0.01 parts by weight or more, 0.05 parts by weight or more, 0.1 parts by weight or more, or 0.2 parts by weight or more. The content of the photoacid-generating agent can be 1.0 parts by weight or less, 0.9 parts by weight or less, 0.8 parts by weight or less, or 0.7 parts by weight or less. From these viewpoints, the content of the photoacid-generating agent can be 0.01 to 1.0 parts by weight, 0.05 to 0.9 parts by weight, 0.1 to 0.8 parts by weight, or 0.2 to 0.7 parts by weight.

[0059] 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, and aromatic hydrocarbon solvents. One organic solvent may be used alone or in combination of two or more.

[0060] From the viewpoint that the content of organic solvent in the photosensitive resin film can be easily adjusted by drying the photosensitive resin composition, the photosensitive resin composition may contain acetate solvents. In the photosensitive element according to this embodiment, acetate solvents may be present in the photosensitive resin film. Examples of acetate solvents include alkylene glycol monoalkyl ether acetates, dialkylene glycol alkyl ether acetates, alkoxyalkyl acetates (e.g., alkoxybutyl acetates such as 3-methoxybutyl acetate (MBA)), 3-methoxy-3-methylbutyl acetate, propylene glycol diacetate, 1,3-butanediol diacetate, 1,4-butanediol diacetate, 1,6-hexanediol diacetate, cyclohexanol acetate, butyl acetate, etc. Examples of alkylene glycol monoalkyl ether acetates include propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether acetate, and propylene glycol monobutyl ether acetate; 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 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.

[0061] From the viewpoint that the content of organic solvent in the photosensitive resin film can be easily adjusted by drying the photosensitive resin composition, the photosensitive resin composition may contain at least one selected from the group consisting of alkylene glycol monoalkyl ether acetate and alkoxyalkyl acetate, or at least one selected from the group consisting of propylene glycol monomethyl ether acetate and 3-methoxybutyl acetate. From the viewpoint that the uniformity of the thickness of the photosensitive resin film can be easily improved, the photosensitive resin composition may contain alkylene glycol monoalkyl ether acetate or propylene glycol monomethyl ether acetate. It is presumed that by using alkylene glycol monoalkyl ether acetate, the overall boiling point of the solvent contained in the photosensitive resin film is easily lowered, thus lowering the drying temperature. Therefore, it is presumed that since the deformation of the first film during heating is easily reduced, the uniformity of the thickness of the photosensitive resin film is easily improved. However, the reasons are not limited to this.

[0062] In the photosensitive element according to this embodiment, from the viewpoint of easily adjusting the content of organic solvent in the photosensitive resin film, at least one selected from the group consisting of alkylene glycol monoalkyl ether acetate and alkoxyalkyl acetate can 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 can 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 solvent in the photosensitive resin film, alkylene glycol monoalkyl ether acetate and propylene glycol monomethyl ether acetate can be present in the photosensitive resin film.

[0063] From the viewpoint that the content of organic solvent in the photosensitive resin film can be easily adjusted by drying the photosensitive resin composition, the photosensitive resin composition may contain an organic solvent having a boiling point (boiling point at atmospheric pressure) within the following range (e.g., an organic solvent with a boiling point less than 150°C). In the photosensitive element according to this embodiment, from the viewpoint that the content of organic solvent in the photosensitive resin film can be easily adjusted, an organic solvent having a boiling point (boiling point at atmospheric pressure) within the following range (e.g., an organic solvent with a boiling point less than 150°C) may be present 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 points of organic solvents can be below 200℃, below 190℃, below 180℃, below 170℃, below 160℃, below 150℃, below 150℃, below 149℃, below 148℃, below 147℃, or below 146℃. From these perspectives, the boiling points of organic solvents can be 100–200℃, 100–180℃, 100–160℃, above 100℃ but below 150℃, 130–200℃, 130–180℃, 130–160℃, above 130℃ but below 150℃, 140–200℃, 140–180℃, 140–160℃, above 140℃ but below 150℃, 150–200℃, or 150–180℃.

[0064] The content of organic solvents with a boiling point (at atmospheric pressure) of less than 150°C is 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, and can be 50.0% by mass or more, greater 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. The organic solvents contained in the photosensitive resin composition or the organic solvents present in the photosensitive resin film can be substantially formed from organic solvents with a boiling point of less than 150°C (meaning that 100% by mass of the organic solvents contained in the photosensitive resin composition or the organic solvents present in the photosensitive resin film are substantially organic solvents with a boiling point of less than 150°C). From the same perspective, the content of compounds or groups of compounds contained in organic solvents with a boiling point (at atmospheric pressure) less than 150°C (e.g., the content of alkylene glycol monoalkyl ether acetates, alkoxyalkyl acetates, propylene glycol monomethyl ether acetates, 3-methoxybutyl acetates, etc.) can also be within the ranges mentioned above. The types and contents of organic solvents present in photosensitive resin films can be confirmed by gas chromatography.

[0065] The content of organic solvents with a boiling point (at atmospheric pressure) less than 150°C, based on the total mass of the photosensitive resin film, can be within the following ranges: The organic solvent content can be 1% or more by mass, 3% or more by mass, 5% or more by mass, 8% or more by mass, 10% or more by mass, 12% or more by mass, 14% or more by mass, 15% or more by mass, 16% or more by mass, or 17% or more by mass. The organic solvent content can be less than 50% by mass, less than 40% by mass, less than 35% by mass, less than 30% by mass, less than 25% by mass, less than 23% by mass, less than 20% by mass, less than 18% by mass, less than 17% by mass, or less than 16% by mass. The organic solvent content can 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 the same perspective, the content of compounds or groups of compounds contained in organic solvents with a boiling point (at atmospheric pressure) less than 150°C (e.g., the content of alkylene glycol monoalkyl ether acetates, alkoxyalkyl acetates, propylene glycol monomethyl ether acetates, 3-methoxybutyl acetates, etc.) can also be within the ranges mentioned above. The content of organic solvents in photosensitive resin films can be confirmed by gas chromatography.

[0066] From the viewpoint of easily obtaining thick conductor patterns, the average thickness of the photosensitive resin film is 150 μm or more. The average thickness of the photosensitive resin film can be 160 μm or more, 170 μm or more, or 180 μm or more. The average thickness of the photosensitive resin film can 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 can be 150–300 μm, 150–250 μm, 150–200 μm, 180–300 μm, 180–250 μm, or 180–200 μm. The average thickness of the photosensitive resin film can be determined by the measurement method described in the experimental examples below.

[0067] The photosensitive element according to this embodiment may include a support layer (support film), a protective layer (protective film), a buffer layer, an adhesive layer, a light-absorbing layer, and a gas-barrier layer. The photosensitive element according to this embodiment may have a first film as the support layer (support film) and a second film as the protective layer (protective film). The photosensitive element according to this embodiment may include layers other than the first and second films.

[0068] Figure 1 This is a schematic cross-sectional view showing an example of a photosensitive element. Figure 1 The photosensitive element 10 includes a support film (first film) 12, a positive photosensitive resin film 14 disposed on the support film 12, and a protective film (second film) 16 disposed on the photosensitive resin film 14. The average thickness of the photosensitive resin film 14 is 150 μm or more. The support film 12 and the protective film 16 are respectively in contact with the photosensitive resin film 14. That is, the photosensitive element 10 includes 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.

[0069] The method for manufacturing a photosensitive element according to this embodiment is a method for obtaining the photosensitive element according to this embodiment. The method includes: a step of coating a positive 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 a step of disposing a second film onto the photosensitive resin film. Drying the photosensitive resin composition removes at least a portion of the organic solvent. According to the method for manufacturing a photosensitive element according to this embodiment, the photosensitive element according to this embodiment can be obtained.

[0070] From the viewpoint of reducing drying time, the drying temperature of the photosensitive resin composition can be above 70°C, above 80°C, above 90°C, or above 100°C. From the viewpoint of easily adjusting the content of organic solvents in the photosensitive resin film, the drying temperature of the photosensitive resin composition can be below 150°C, below 140°C, below 130°C, below 120°C, or below 110°C. From these viewpoints, the drying temperature of the photosensitive resin composition can be 70–150°C, 80–140°C, 80–120°C, 90–130°C, 100–120°C, or 100–110°C.

[0071] From the viewpoint of excellent storage stability of the photosensitive resin film, the drying time of the photosensitive resin composition can be 6 minutes or more, 10 minutes or more, 12 minutes or more, or 14 minutes or more. From the viewpoint of excellent operability of the photosensitive resin film, the drying time of the photosensitive resin composition can be 80 minutes or less, 70 minutes or less, 60 minutes or less, 55 minutes or less, or 50 minutes or less. From these viewpoints, the drying time of the photosensitive resin composition can be 6–80 minutes, 8–70 minutes, 10–60 minutes, 12–55 minutes, or 14–50 minutes. The drying time of the photosensitive resin composition can be adjusted according to the drying temperature.

[0072] The method for manufacturing a resist pattern according to this embodiment includes the following steps: a placement step in which a photosensitive resin film of a photosensitive element according to this embodiment is placed on a substrate while one of the first film and the second film is removed and the photosensitive resin film is located on the substrate side relative to the other of the first film and the second film; an exposure step in which a portion of the photosensitive resin film is exposed; and a development step in which at least a portion (partial or complete) of the exposed portion of the photosensitive resin film is removed to form a resist pattern.

[0073] In the configuration process, one of the first and second films (hereinafter referred to as "film F1") is removed, and the photosensitive resin film of the photosensitive element according to this embodiment is disposed on the substrate with the photosensitive resin film located on the substrate side relative to the other of the first and second films (hereinafter referred to as "film F2").

[0074] In the preparation process, the photosensitive resin film can be placed on the substrate while it is in contact with the substrate. When the photosensitive resin film is placed on the substrate, it can be pressed onto the substrate while being heated. The heating temperature during pressing can be, for example, 70–130°C, and the pressing pressure can be, for example, 0.1–1.0 MPa (1–10 kgf / cm²). 2 However, these conditions can be selected appropriately as needed. The configuration process can be carried out under reduced pressure.

[0075] The substrate may have a conductor layer, or it may have an insulating layer and a conductor layer disposed on the insulating layer. There are no particular limitations on the substrate, and examples include circuit board substrates having an insulating layer and a conductor layer disposed on the insulating layer; chip pads (lead frame substrates) such as alloy substrates; silicon substrates; glass substrates, etc.

[0076] In the exposure process, a portion of the photosensitive resin film is exposed. In the exposure process, the photosensitive resin film can be exposed using active light. In the exposure process, the photosensitive resin film can be exposed with the film F2 removed, or it can be exposed with the film F2 in between using active light.

[0077] As an exposure method, known exposure methods can be used without particular restrictions. Examples include the method of illuminating active light in an image-like manner through a positive mask pattern called the original image (mask exposure method), LDI (Laser Direct Imaging) exposure method, and the method of illuminating active light with a projected photomask image through a lens in an image-like manner (projection exposure method).

[0078] As a source of active light, known light sources can be used without particular restrictions, including light sources that radiate ultraviolet light. Examples of light sources that radiate ultraviolet light include carbon arc lamps, mercury vapor arc lamps, high-pressure mercury lamps, xenon lamps, gas lasers (argon lasers, etc.), solid-state lasers (YAG lasers, etc.), and semiconductor lasers (gallium nitride-based blue-violet lasers, etc.).

[0079] In the developing process, at least a portion of the exposed portion of the photosensitive resin film is removed to form a resist pattern. If film F2 is disposed on the photosensitive resin film during the exposure process, the developing process can be performed after removing film F2. The developing method can be wet developing or dry developing.

[0080] In the case of wet development, a developer solution corresponding to the structure of the photosensitive resin film can be used, and development can be performed using a known wet development method. Examples of wet development methods include immersion, rotary immersion, high-pressure spraying, brushing, scrubbing, and agitation immersion. One wet development method can be used alone or in combination of two or more.

[0081] The developer can be appropriately selected based on the structure of the photosensitive resin film. Examples of developers include alkaline aqueous solutions and organic solvent developers.

[0082] Examples of bases that can be used as alkaline aqueous solutions include: hydroxides such as lithium, sodium, or potassium hydroxides; 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; morpholine, etc.

[0083] Organic solvents used as organic solvents in developers include 1,1,1-trichloroethane, N-methyl-2-pyrrolidone, N,N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone.

[0084] The method for manufacturing resist patterns 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 before the configuration step.

[0085] The method for manufacturing a resist pattern according to this embodiment may include a step of removing (peeling off) film F1 from the photosensitive element before the application step. The method for manufacturing a resist pattern according to this embodiment may include a step of removing (peeling off) film F2 from the photosensitive element between the application step and the exposure step, or between the exposure step and the development step.

[0086] From the viewpoint of reducing residual solvent in the photosensitive resin film, the method for manufacturing the resist pattern according to this embodiment may include a heating step (hereinafter referred to as "first heating step") in which the photosensitive resin film is heated between the preparation step and the exposure step, or it may include a step in which the photosensitive resin film is heated while the film F2 has been removed.

[0087] The heating temperature in the first heating step can be above 50°C, 60°C, 70°C, 80°C, 90°C, or 100°C. The heating temperature can be below 200°C, 190°C, 180°C, 170°C, 160°C, or 150°C. From these perspectives, the heating temperature can be 50–200°C, 60–180°C, or 80–160°C. The first heating step can consist of multiple steps with different heating temperatures.

[0088] From the viewpoint of improving the adhesion to the substrate, the method for manufacturing the resist pattern according to this embodiment may include a heating step (hereinafter referred to as "second heating step") in which the photosensitive resin film is heated between the exposure step and the development step.

[0089] The heating temperature in the second heating step can be above 50°C, 60°C, 70°C, 80°C, 90°C, or 100°C. The heating temperature can be below 250°C, 230°C, 210°C, 200°C, 190°C, or 180°C. From these perspectives, the heating temperature can be 50–250°C, 60–200°C, or 80–180°C. The second heating step can consist of multiple steps with different heating temperatures.

[0090] The method for manufacturing resist patterns according to this embodiment may include a step of heating or exposing the resist pattern after the developing step.

[0091] Figure 2 and Figure 3 This is a schematic cross-sectional view illustrating an example of a method for manufacturing a resist pattern, specifically an example of a method for manufacturing a resist pattern using a photosensitive resin film with positive photosensitive properties. Figure 2 In (a), a substrate 20 is prepared. The substrate 20 includes an insulating layer 22 and a conductor layer 24 disposed on the insulating layer 22. The conductor layer 24 is, for example, a copper layer. Figure 2 In (b), remove Figure 1 After the protective film 16 of the photosensitive element 10 is applied, the photosensitive resin film 14 and the support film 12 of the photosensitive element 10 are laminated onto the substrate 20. Figure 2 In step (c), after removing the support film 12, the photosensitive resin film 14 is heated. Figure 3 In (a), an exposure section 14a is formed on the photosensitive resin film 14 by irradiating it with an active light L that projects a photomask image (exposure by projection exposure). Figure 3 In (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.

[0092] The method for manufacturing a conductor pattern according to this embodiment includes a step of forming a conductor pattern by using a resist pattern obtained by the method for manufacturing a resist pattern according to this embodiment as a mask. In the method for manufacturing a conductor pattern according to this embodiment, the conductor pattern can be formed by performing a plating or etching process using the resist pattern obtained by the method for manufacturing a resist pattern according to this embodiment as a mask, or by performing a plating or etching process on a substrate on which the resist pattern obtained by the method for manufacturing a resist pattern according to this embodiment is formed. Examples of materials constituting the conductor pattern include copper, solder, nickel, and gold.

[0093] In the method for manufacturing a conductor pattern according to the first embodiment, a conductor pattern is formed by using a resist pattern obtained by the resist pattern manufacturing method according to this embodiment as a mask to perform a plating process on at least a portion (or all) of the portion of the substrate where no resist pattern is formed. In the method for manufacturing a conductor pattern according to the first embodiment, a conductor pattern can be formed by using the resist pattern as a mask while 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, and then performing a plating process on at least a portion (or all) of the portion of the conductor layer of the substrate where no resist pattern is formed. The materials of the conductor layer of the substrate and the plating layer (conductor layer) formed in the plating process can be the same or different from each other. When the materials of the conductor layer of the substrate and the plating layer (conductor layer) formed in the plating process are the same, the conductor layer and the plating layer can be integrated. The plating process can be an electrolytic plating process or an electroless plating process. Examples of plating processes include copper plating, solder plating, nickel plating, and gold plating.

[0094] In the method for manufacturing a conductor pattern according to the second embodiment, with a substrate having a conductor layer and a resist pattern obtained by the resist pattern manufacturing method according to this embodiment formed on the conductor layer, the resist pattern is used as a mask to etch away at least a portion (partial or all) of the conductor layer not covered by the resist pattern, thereby forming a conductor pattern covered by the resist pattern. The etching method can be appropriately selected depending on the conductor layer to be removed.

[0095] The method for manufacturing conductor patterns according to this embodiment may include a step of removing the resist pattern on a substrate after a plating or etching process. The resist pattern can be removed, for example, by an aqueous solution that is more alkaline than the alkaline aqueous solution used in the developing process.

[0096] In the method for manufacturing a conductor pattern according to the first embodiment, if the substrate has a conductor layer, the portion of the conductor layer of the substrate covered by the resist pattern can be removed by etching (e.g., flash etching) after the resist pattern is removed. The etching method can be appropriately selected depending on the conductor layer to be removed.

[0097] One embodiment of the conductor pattern manufacturing method is a circuit board manufacturing method (e.g., a printed circuit board manufacturing method). This circuit board manufacturing method includes the following steps: using a resist pattern obtained by the resist pattern manufacturing method of this embodiment as a mask to form a circuit pattern (e.g., a circuit) as a conductor pattern. The circuit board of this embodiment can be obtained by the circuit board manufacturing method of this embodiment. The circuit board of this embodiment can be a single-layer printed circuit board, a multi-layer printed circuit board, or a printed circuit board with small-diameter through-holes.

[0098] Figure 4 This is a schematic cross-sectional view illustrating an example of a method for manufacturing a conductor pattern, showing the use of... Figure 3 A schematic cross-sectional view illustrating an example of a method for manufacturing the conductor pattern of resist pattern 14b. Figure 4 In (a), a plating layer 30 is formed on the conductor layer 24 of the substrate 20 that is not covered by the resist pattern 14b by using a plating process with the resist pattern 14b as a mask. Figure 4 In (b), after removing the resist pattern 14b, a conductor layer 24a is formed by removing the portion of the conductor layer 24 covered by the resist pattern 14b. Thus, a conductor pattern 40 consisting of the conductor layer 24a and the plating layer 30 is formed.

[0099] Example

[0100] The present invention will be further illustrated by the following experimental examples, but the present invention is not limited to the following experimental examples.

[0101] <Fabrication of Photosensitive Elements>

[0102] (Experimental Example 1)

[0103] As a support film, a polyethylene terephthalate film (manufactured by TOYOBO CO.,LTD., trade name "A-5300", width: 590 mm) with an average thickness of 50 μm was prepared. Next, a positive photosensitive resin composition (non-volatile component: 50% by mass) containing propylene glycol monomethyl ether acetate (PGMEA) as an organic solvent was prepared using TOKYO OHKA KOGYO CO., LTD., trade name "PMER P-BZ4000". After coating the positive photosensitive resin composition onto the support film in a direction orthogonal to the width direction of the support film, it was dried at 100°C for 40 minutes using a hot air convection dryer, thereby forming a photosensitive resin film (average thickness after drying: 180 μm). Next, a laminate A was obtained by laminating a biaxially stretched polypropylene film (manufactured by Oji F-Tex Co., Ltd., trade name "MA-420") with an average thickness of 40 μm as a protective film onto the photosensitive resin film. Then, with the protective film positioned on the upper side of the photosensitive resin film in a more vertical direction than the photosensitive resin film, the laminate A was pressed using a roller laminator (manufactured by MCK Co., Ltd., trade name "MRK-650Y") at a temperature of 70°C (upper and lower rollers), a roller speed of 1.3 m / min, and a pressure of 0.5 MPa, thereby producing a photosensitive element consisting of a support film, a photosensitive resin film, and a protective film stacked sequentially.

[0104] (Experimental Example 2)

[0105] The support film was changed to a polyethylene terephthalate film with an average thickness of 100 μm (manufactured by TOYOBO CO., LTD., trade name "TN200", width: 590 mm), and the same procedure as in Experimental Example 1 was followed to fabricate a photosensitive element.

[0106] (Experimental Example 3)

[0107] Using the trade name "PMER P-BZ4000" manufactured by TOKYO OHKA KOGYO CO., LTD., a positive photosensitive resin composition (non-volatile component: 50% by mass) containing 3-methoxybutyl acetate (MBA) as an organic solvent was prepared. Otherwise, the process was carried out in the same manner as in Experimental Example 1, thereby producing a photosensitive element.

[0108] (Example for reference)

[0109] The average thickness of the dried photosensitive resin film was changed to 120 μm, and otherwise the same procedure as in Experimental Example 3 was followed, thereby fabricating a photosensitive element.

[0110] <Determination of Residual Solvents>

[0111] 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 and protective films from the photosensitive element, the photosensitive resin film was dissolved in acetone, and the residual solvent in the photosensitive resin film was determined by gas chromatography. Propylene glycol monomethyl ether acetate was confirmed to be present in the photosensitive resin films of Examples 1 and 2, with a content of propylene glycol monomethyl ether acetate based on the total mass of the photosensitive resin film of 16.1% by mass in Example 1 and 15.4% by mass in Example 2. 3-methoxybutyl acetate was confirmed to be present in the photosensitive resin film of Example 3, with a content of 3-methoxybutyl acetate based on the total mass of the photosensitive resin film of 17.2% by mass in Example 3.

[0112] Measurement device: Agilent Technologies GC 7890B

[0113] Carrier gas: Nitrogen, 5.0 mL / min

[0114] Column: DB-WAX Polyethylene Glycol (0.53mm ID×30m, 1.0μm)

[0115] Oven temperature: After heating at 60℃ for 5 minutes, increase the temperature to 200℃ at a rate of 20℃ / minute.

[0116] Detector: FID

[0117] <Determination of average thickness>

[0118] The average thicknesses of the support film, photosensitive resin film, and protective film were measured in the following order. First, a test piece measuring 50 mm in length and 320 mm in width (width = the width direction of the support film) was obtained by cutting the photosensitive element. Marks were made on the surfaces of the support film and the protective film at the center of the test piece, two locations 60 mm apart laterally from the center, and two locations 120 mm apart laterally from the center. The thickness of these five locations (marked locations) on the photosensitive element was measured using a contact thickness gauge (manufactured by Mitutoyo Corporation, trade name "VL-50"), thereby obtaining the average thickness of the photosensitive element. After peeling off the protective film, the thickness of the five locations (marked locations) on the protective film was measured using the same contact thickness gauge, thereby obtaining the average thickness of the protective film. After peeling off the support film, the thickness of the five locations (marked locations) on the support film was measured using the same contact thickness gauge, thereby obtaining the average thickness of the support film. 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 element.

[0119] <Uniformity of thickness of photosensitive resin film>

[0120] The thickness of the photosensitive resin film in the photosensitive element was measured every 10 mm along the width of the support film using a contact thickness gauge (manufactured by Mitutoyo Corporation, trade 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.

[0121] For a position (30 mm) at one end of the photosensitive resin film along the width direction of the support film, the difference A between the thickness of the photosensitive resin film and its average thickness was calculated. Cases where the difference A is less than 10 μm were classified as "A", cases where the difference A is greater than 10 μm but less than 30 μm were classified as "B", and cases where the difference A is greater than 30 μm were classified as "C". The results are shown in Table 1.

[0122] For the central portion (the central 240 mm region) of the photosensitive resin film along the width direction of the support film, the difference B between the maximum and minimum thickness of the photosensitive resin film was calculated. Cases with a difference B less than 10 μm were classified as "A", cases with a difference B greater than 10 μm but less than 20 μm were classified as "B", and cases with a difference B greater than 20 μm were classified as "C". The results are shown in Table 1.

[0123] [Table 1]

[0124]

[0125] Symbol Explanation

[0126] 10-Photosensitive element, 12-Support film, 14-Photosensitive resin film, 14a-Exposure part, 14b-Resist pattern, 16-Protective film, 20-Substrate, 22-Insulating layer, 24, 24a-Conductor layer, 30-Platinum layer, 40-Conductor pattern, L-Active light.

Claims

1. A photosensitive element comprising: A first film, a positive photosensitive resin film disposed on the first film, and a second film disposed on the photosensitive resin film. 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 150–300 μm.

3. The photosensitive element according to claim 1, wherein, Acetate solvents are present in the photosensitive resin film.

4. The photosensitive element according to claim 1, wherein, 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 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 membrane is greater than 50 μm.

7. A method for manufacturing a resist pattern, comprising the following steps: In the configuration step, with one of the first film and the second film removed and the photosensitive resin film located on the substrate side relative to the other of the first film and the second film, the photosensitive resin film of the photosensitive element according to any one of claims 1 to 6 is configured on the substrate. The exposure process involves exposing a portion of the photosensitive resin film. and The developing process removes at least a portion 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, wherein, Between the configuration step and the exposure step, there is also a step of heating the photosensitive resin film while the other film has been removed.

9. The method for manufacturing a resist pattern according to claim 7, wherein, Between the exposure step and the development step, there is also a step of heating the photosensitive resin film.

10. A method for manufacturing a conductor pattern, comprising: The process of using the resist pattern obtained by the resist pattern manufacturing method of claim 7 as a mask to form a conductor pattern.

11. A method for manufacturing a photosensitive element, comprising: The process of forming a photosensitive resin film with an average thickness of 150 μm or more by coating a positive photosensitive resin composition onto a first film and then drying the photosensitive resin composition; and The process of applying the second film onto 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 150–300 μm.

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

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

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

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