Photosensitive resin composition

Abstract

A photosensitive resin composition characterized by containing: (A) an alkali-soluble polymer; (B) a compound containing an ethylenically unsaturated bond; and (C) a photopolymerization initiator; the alkali-soluble polymer (A) contains 10-24 mass% of structural units of (meth) acrylic acid and 35-90 mass% of structural units of styrene based on the total mass of the monomers constituting the alkali-soluble polymer (A), and the weight-average molecular weight of the compound (B) containing an ethylenically unsaturated bond is 1200-5000.

Description

[0001] This application is a divisional application of an application with an application date of September 7, 2016, an application number of 201680052525.7, and an invention title of photosensitive resin composition (application number 202111430178.6, invention title photosensitive resin composition). Technical Field

[0002] <Technical field related to the first embodiment of the present invention>

[0003] The first embodiment of the present invention relates to a photosensitive resin composition.

[0004] <Technical field related to the second embodiment of the present invention>

[0005] The second embodiment of the present invention relates to a photosensitive resin composition and the like.

[0006] <Technical field related to the third embodiment of the present invention>

[0007] The third embodiment of the present invention relates to a photosensitive resin composition and the like.

[0008] <Technical field related to the fourth embodiment of the present invention>

[0009] The fourth embodiment of the present invention relates to a photosensitive resin composition. Background Art

[0010] <Background art related to the first embodiment of the present invention>

[0011] Printed circuit boards are usually manufactured by photolithography. Photolithography refers to a method in which a layer formed of a photosensitive resin composition is formed on a substrate, a resist pattern is formed by pattern exposure and development of the coating film, then a conductor pattern is formed by etching or plating treatment, and then the resist pattern on the substrate is removed, thereby forming a desired wiring pattern on the substrate.

[0012] In this photolithography method, when forming a photosensitive resin composition layer on a substrate, known methods include: a method of removing a solvent after coating a composition solution; a method of laminating a photosensitive element or a dry film resist layer formed by laminating a support and a photosensitive resin composition layer on a substrate and then peeling off the support, etc.

[0013] In the manufacture of printed circuit boards, photosensitive elements are often used. There are many known examples of methods for forming wiring patterns using such photosensitive elements and photosensitive resin compositions suitable therefor.

[0014] For example, separately, Patent Document 1 discloses a method for easily forming a copper wiring pattern having a good cross-sectional shape, and a photosensitive resin composition used in this method;

[0015] Patent Document 2 discloses a photosensitive resin composition containing a specific addition polymerizable monomer having an ethylenic double bond.

[0016] However, in recent years, due to the high density of printed circuit boards, substrates tend to be multilayered. In a multilayer substrate, vias are provided to make the upper and lower stacked substrates conductive. When forming a wiring pattern on a substrate with vias used in a multilayer substrate by photolithography, the resist film (cover film) formed on the vias is required to have the property of not being damaged by the spray pressure during development, water washing, etc. (cover film breakage resistance or coverability).

[0017] Regarding this point, Patent Document 3 discloses a photosensitive resin composition containing a binder polymer with a small dispersity (Mw / Mn), a photopolymerizable compound, and an acridine compound, and explains that a resist film with excellent coverability can be formed using this composition.

[0018] <Background Art Related to the Second Embodiment of the Present Invention>

[0019] Printed circuit boards are usually manufactured by photolithography. Photolithography refers to a method of forming a coating film containing a layer formed from a photosensitive resin composition on a substrate, performing pattern exposure and development on the coating film to form a resist pattern, then forming a conductor pattern by etching or plating treatment, and then removing the resist pattern on the substrate, thereby forming a desired wiring pattern on the substrate.

[0020] In photolithography, when forming a photosensitive resin layer on a substrate, the following are known: a method of removing the solvent after coating the composition solution; a method of laminating a photosensitive element or a dry film resist formed by laminating a support and a photosensitive resin layer on the substrate and then peeling off the aforementioned support, etc.

[0021] In the manufacture of printed circuit boards, photosensitive elements are often used. There are many known examples of methods for forming a wiring pattern using this photosensitive element and photosensitive resin compositions suitable therefor.

[0022] For example, separately, Patent Document 1 discloses a method for easily forming a copper wiring pattern having a good cross-sectional shape, and a photosensitive resin composition used in this method, and Patent Document 4 discloses a photosensitive resin composition containing a specific addition polymerizable monomer having an ethylenic double bond.

[0023] <Background Art Related to the Third Embodiment of the Present Invention>

[0024] Heretofore, printed circuit boards have generally been manufactured by photolithography. In photolithography, first, a photosensitive resin composition layer laminated on a substrate is pattern-exposed. In the case of a negative type, the exposed portion of the photosensitive resin composition undergoes polymerization and curing, or in the case of a positive type, it becomes soluble in a developer. Next, the unexposed portion (negative type) or the exposed portion (positive type) is removed with a developer to form a resist pattern on the substrate. Further, after performing an etching or plating process to form a conductor pattern, the resist pattern is peeled off and removed from the substrate. Through these processes, a conductor pattern is formed on the substrate.

[0025] In photolithography, a method of coating a solution of a photosensitive resin composition on a substrate and drying it, or a method of laminating a photosensitive resin composition layer of a dry film resist (a photosensitive resin laminate in which a photosensitive resin composition layer is laminated on a support) on a substrate is generally used. The latter is often used in the manufacture of printed circuit boards.

[0026] With the recent miniaturization of wiring pitches in printed circuit boards, various characteristics are required for dry film resists. Along with the miniaturization of wiring pitches, the thickness of dry film resists also tends to become thinner, but strong via covering properties are still required to protect vias on the substrate.

[0027] In addition, when developing the resist pattern, due to the moisture remaining between the patterns, resist components dissolve between the patterns, causing a water residue short circuit failure. To reduce this water residue short circuit failure, it is necessary to improve the hydrophobicity of the cured resist.

[0028] To improve the properties of the resist, various photosensitive resin compositions have been proposed (Patent Documents 5 and 6).

[0029] <Background Art Related to the Fourth Embodiment of the Present Invention>

[0030] Printed circuit boards are generally manufactured by photolithography. Photolithography refers to a method in which a layer formed of a photosensitive resin composition is formed on a substrate, the coating film is pattern-exposed and developed to form a resist pattern, and then after forming a conductor pattern by an etching or plating process, the resist pattern on the substrate is removed, thereby forming a desired wiring pattern on the substrate.

[0031] In photolithography, when forming a photosensitive resin layer on a substrate, a method of removing the solvent after coating the composition solution; a method of laminating a photosensitive element or a dry film resist in which a support and a photosensitive resin layer are laminated on the substrate and then peeling off the support, etc. are known.

[0032] In the manufacture of printed circuit boards, photosensitive elements are often used. A method for forming a wiring pattern using such a photosensitive element and a photosensitive resin composition suitable therefor are known (Patent Documents 1 and 2). Patent Document 1 describes a conventional method for forming a copper wiring pattern having a good cross-sectional shape and a photosensitive resin composition used therefor. Patent Document 2 describes a photosensitive resin composition containing a specific addition-polymerizable monomer having an ethylenically unsaturated bond.

[0033] With the recent miniaturization of wiring intervals in printed circuit boards, characteristics such as resolution are required for dry film resists. For example, in order to improve the characteristics of resist patterns, various photosensitive resin compositions have been proposed (Patent Documents 5 and 6).

[0034] Prior Art Documents

[0035] Patent Documents

[0036] Patent Document 1: Japanese Patent Application Laid-Open No. 2011-233769

[0037] Patent Document 2: International Publication No. 2009 / 022724

[0038] Patent Document 3: Japanese Patent Application Laid-Open No. 2013-109321

[0039] Patent Document 4: Japanese Patent Application Laid-Open No. 2015-60120

[0040] Patent Document 5: International Publication No. 2015 / 098870

[0041] Patent Document 6: Japanese Patent Application Laid-Open No. 2014-048340 Summary of the Invention

[0042] Problems to be Solved by the Invention

[0043] <Problems to be Solved by the First Embodiment of the Present Invention>

[0044] In recent years, the manufacturing of circuit boards has generally been carried out by a production line that sequentially processes the substrates while fixing the conveyance direction of the substrate edges. Here, when forming a conductor pattern such as a line / space pattern on the substrate, there are cases where the lines of the conductor are parallel (lines in the MD direction), perpendicular (lines in the TD direction), or skewed with respect to the conveyance direction of the substrate. When forming a conductor pattern of a line / space pattern by a production line using a conventional resist material, the wiring widths of the lines in the MD direction and the TD direction are different, resulting in a so-called aspect ratio difference in wiring width. In many cases, the lines in the MD direction are more easily eroded by the etching solution than the lines in the TD direction, so there is a tendency for the amount of etching to increase and the wiring width to become thinner. In order to form a fine conductor pattern by a production line, it is preferable to reduce the wiring width difference between the wiring in the MD direction and the wiring in the TD direction.

[0045] However, in the prior art represented by the above Patent Documents 1 to 3, no research has been conducted from this perspective, and a resist material for reducing the aspect ratio difference in wiring width remains unknown.

[0046] The first embodiment of the present invention has been made in view of the above situation. Therefore, an object of the first embodiment of the present invention is to provide a resist material that suppresses the aspect ratio difference in wiring width when forming a fine conductor pattern by a production line.

[0047] <Problems to be Solved by the Second Embodiment of the Present Invention>

[0048] In order to form a resist pattern using a photosensitive resin composition, a developing process is required. In this developing process, respectively, in the case of a positive-type composition, the composition in the exposed area is dissolved and removed, and in the case of a negative-type composition, the composition in the exposed area is dissolved and removed to form a resist pattern. In this developing process, not all of the composition in the unnecessary area is "dissolved" in the developer, but at least a part of it remains undissolved and is dispersed in the developer, and thus is removed from the substrate. Therefore, each time the developing process is repeated, the amount of unnecessary substances in the developer increases, and finally, undissolved components with poor dispersibility sometimes form aggregates. Such aggregates adhere to the substrate to be developed later and remain, sometimes causing short-circuit failures and the like.

[0049] Therefore, from the viewpoint of improving the product yield in the developing process and further reducing the manufacturing cost of printed circuit boards, there is a strong expectation that the photosensitive resin composition used has good developer dispersibility.

[0050] In recent years, the requirements for miniaturization and refinement of printed circuit boards have been increasing day by day. Therefore, for the photosensitive resin composition used in the formation of such printed circuit boards, the ability to form fine patterns is also required. Here, the minimum size of the pattern formed on the substrate depends on the exposure wavelength. Therefore, in theory, it is not very difficult to form a miniaturized pattern by exposure using a photosensitive polymerization initiator corresponding to the exposure wavelength used. However, fine patterns formed by exposure with a size of, for example, several tens of μm or less sometimes peel off from the substrate in subsequent processes such as the development process. As a result, the miniaturization of printed circuit boards is restricted.

[0051] Therefore, in order to form a fine printed circuit board, a photosensitive resin composition with high adhesion of fine patterns is required.

[0052] However, the photosensitive resin compositions described in Patent Documents 1 and 4 cannot meet the current stringent requirements in terms of both development dispersibility and adhesion of fine patterns, and there is still room for improvement in this field.

[0053] The second embodiment of the present invention is made in view of this situation.

[0054] Therefore, the object of the second embodiment of the present invention is to provide a novel photosensitive material that has high-level properties such as resolution typically required for photosensitive materials, and excellent development dispersibility and adhesion of fine patterns.

[0055] <Problems to be Solved by the Third Embodiment of the Present Invention>

[0056] In Patent Document 5, from the viewpoints of the developability of the photosensitive resin composition, the resolution, adhesion, and flexibility of the resist pattern, a binder polymer having a structural unit of (meth)acrylic acid, a structural unit of styrene or α-methylstyrene, and a structural unit of (meth)acrylic acid hydroxyalkyl ester having a hydroxyalkyl group with 1 to 12 carbon atoms, and a combination with a bisphenol type di(meth)acrylate monomer having 1 to 20 structural units of ethyleneoxy and 0 to 7 structural units of propyleneoxy were studied for the photosensitive resin composition.

[0057] In Patent Document 6, from the viewpoints of the interval width and hole covering property of the positive resist pattern, the content of the structural unit of styrene or styrene derivative in the alkali-soluble polymer was proposed to be 30% by mass or more, and the weight average molecular weight of the addition polymerizable monomer was proposed to be 1100 or more.

[0058] Patent Documents 5 and 6 both focus on a photosensitive resin composition containing a polymer having a structural unit with styrene in a specific ratio and a specific monomer. However, the photosensitive resin compositions described in Patent Documents 5 and 6 still have room for improvement from the perspective of balancing the hole covering property of the resist pattern and the suppression of water residue short-circuit failures.

[0059] Therefore, the problem to be solved in the third embodiment of the present invention is to provide a photosensitive resin composition capable of balancing the hole covering property of the resist pattern and the suppression of water residue short-circuit failures.

[0060] <Problems to be Solved in the Fourth Embodiment of the Present Invention>

[0061] In recent years, the manufacture of circuit boards is usually carried out by a production line that conveys the substrate along the fixed direction of the substrate edge and processes it sequentially. At this time, the treatment of the developing solution or etching solution for the substrate is carried out by spraying. In the formation of a resist pattern based on photolithography, it is important that there is no deviation in the line width of the developed resist. However, in the formation of a resist pattern based on spray development, when the development time is short, it is easy to generate a deviation of the developing solution within the substrate surface, and sometimes the above problems occur. Therefore, an extension of the development time is required.

[0062] Here, the development time refers to the time when the substrate stays in the developing tank for development treatment. For example, it is determined as a time that is 2 times the minimum development time, etc. The minimum development time refers to the minimum time required until the unexposed portion of the photosensitive resin layer is completely dissolved and removed, and it varies depending on the concentration or temperature of the developing solution, the spraying direction or spraying amount, pressure, vibration frequency, etc.

[0063] Here, it is considered that the dissolution reaction of the resist based on development occurs mainly under the control of the diffusion of the developing solution. Therefore, from the perspective of promoting development, it is necessary to actively supply the developing solution to the substrate based on spraying or the like. This supply takes some time. Therefore, it can be considered that when the development time is short, the supply of the developing solution cannot sufficiently cover the entire substrate surface, and the deviation of the resist line width becomes significantly larger. On the other hand, it can be considered that when the development time is long, the supply of the developing solution on the substrate becomes uniform, and thus the deviation of the line width also becomes smaller. Therefore, it can be considered that using a photosensitive resin composition with a relatively slow minimum development time itself is effective from the perspective of suppressing the deviation of the line width.

[0064] In Patent Document 5, from the viewpoints of the developability of the photosensitive resin composition, the resolution, adhesion, and flexibility of the resist pattern, regarding the photosensitive resin composition, a binder polymer having a structural unit of (meth)acrylic acid, a structural unit of styrene or α-methylstyrene, and a structural unit of (meth)acrylic acid hydroxyalkyl ester having a hydroxyalkyl group with 1 to 12 carbon atoms, and a combination with a bisphenol type di(meth)acrylate monomer having 1 to 20 structural units of ethylene oxide and 0 to 7 structural units of propylene oxide were studied.

[0065] In Patent Document 6, from the viewpoints of the space width and hole covering property of the positive resist pattern, as the content of the structural unit of styrene or styrene derivative in the alkali-soluble polymer, 30% by mass or more was proposed, and as the weight average molecular weight of the addition polymerizable monomer, 1100 or more was proposed.

[0066] Both Patent Documents 5 and 6 focused on the photosensitive resin composition containing a polymer having a structural unit of styrene in a specific ratio and a specific monomer, but the photosensitive resin compositions described in Patent Documents 5 and 6 still have room for improvement from the viewpoint of achieving both good resolution of the resist pattern and extension of the minimum development time.

[0067] Therefore, the problem to be solved in the fourth embodiment of the present invention is to provide a photosensitive resin composition capable of achieving both good resolution of the resist pattern and extension of the minimum development time.

[0068] Solutions for Solving the Problems

[0069] <Means for Solving the First Problem>

[0070] The inventors of the present invention found that the above object can be achieved by the following technical means, and completed the first embodiment of the present invention. The first embodiment of the present invention is as follows. [1]

[0072] A photosensitive resin composition, characterized by containing the following components (A) to (C),

[0073] Component (A): An alkali-soluble polymer,

[0074] Component (B): A compound having an ethylenic double bond, and

[0075] Component (C): A photopolymerization initiator

[0076] On a copper-clad laminate with a copper foil having a thickness of 18 μm, a photosensitive resin layer formed from the aforementioned photosensitive resin composition is laminated with a thickness of 25 μm. After patternwise light irradiation with a line / space = 50 μm / 30 μm and development treatment, a cured resist pattern is formed. After performing a copper etching treatment at 50 °C for 55 seconds, the bottom width of the copper wire pattern obtained by removing the aforementioned cured resist pattern is 38 μm or more. [2]

[0078] The photosensitive resin composition according to [1], wherein the aforementioned component (A) is a copolymer in which the content ratio of (meth)acrylic acid units is 10% by mass or more and 24% by mass or less. [3]

[0080] The photosensitive resin composition according to [1] or [2], wherein the aforementioned component (A) is a copolymer in which the content ratio of styrene units is 32% by mass or more and 60% by mass or less. [4]

[0082] The photosensitive resin composition according to any one of [1] to [3], wherein the aforementioned component (C) contains an acridine compound. [5]

[0084] The photosensitive resin composition according to any one of [1] to [4], wherein the aforementioned component (B) contains a pentaerythritol compound. [6]

[0086] The photosensitive resin composition according to any one of [1] to [5], wherein the aforementioned component (B) contains a trimethylolpropane compound. [7]

[0088] The photosensitive resin composition according to any one of [1] to [6], wherein the aforementioned component (B) contains a bisphenol A compound. [8]

[0090] A photosensitive resin composition containing the following components (A) to (C),

[0091] Component (A): An alkali-soluble polymer,

[0092] Component (B): A compound having an ethylenic double bond, and

[0093] Component (C): A photopolymerization initiator

[0094] The aforementioned component (A) contains a copolymer in which the content ratio of (meth)acrylic acid units is 10% by mass or more and 24% by mass or less, and the content ratio of styrene units is 32% by mass or more,

[0095] The above-mentioned component (C) contains an acridine compound. [9]

[0097] The photosensitive resin composition according to [8], wherein the above-mentioned component (A) contains a copolymer in which the content ratio of (meth)acrylic acid units is 10% by mass or more and 24% by mass or less, and the content ratio of styrene units is 32% by mass or more and 60% by mass or less.

[10]

[0099] The photosensitive resin composition according to [8] or [9], wherein the above-mentioned component (B) contains a pentaerythritol compound.

[11]

[0101] The photosensitive resin composition according to any one of [8] to

[10] , wherein the above-mentioned component (B) contains a trimethylolpropane compound.

[12]

[0103] The photosensitive resin composition according to any one of [8] to

[11] , wherein the above-mentioned component (B) contains a bisphenol A compound.

[13]

[0105] A photosensitive element obtained by laminating a photosensitive resin layer formed from the photosensitive resin composition according to any one of [1] to

[12] on a support.

[14]

[0107] A method for forming an etching pattern, characterized by comprising:

[0108] A lamination step of laminating the photosensitive resin layer of the photosensitive element according to

[13] on a conductor substrate,

[0109] An exposure step of exposing the laminated photosensitive resin composition layer, and

[0110] A development step of removing the unexposed portion after the above-mentioned exposure with a developer.

[15]

[0112] The method for forming an etching pattern according to

[14] , wherein the above-mentioned lamination step is a step of laminating the photosensitive resin layer of the photosensitive element on the conductor substrate with a wetting agent interposed therebetween.

[16]

[0114] A method for manufacturing a circuit board, characterized by comprising:

[0115] A lamination step of laminating the photosensitive resin composition layer of the photosensitive element according to

[13] on a conductor substrate,

[0116] An exposure step of exposing the stacked photosensitive resin composition layers,

[0117] A developing step of removing the unexposed portions after the aforementioned exposure with a developer,

[0118] A conductor pattern forming step of etching or plating a conductor substrate having an anti-etching pattern formed by the aforementioned development, and

[0119] A stripping step of stripping the aforementioned anti-etching pattern.

[17]

[0121] According to the method for manufacturing a circuit board described in

[16] , wherein the aforementioned lamination step is a step of laminating a photosensitive resin layer of a photosensitive element on a conductor substrate with a wetting agent interposed therebetween.

[0122] <Means for Solving the Second Problem>

[0123] The inventors found that the above object can be achieved by the following technical means, and completed the second embodiment of the present invention. The second embodiment of the present invention is as follows. [1]

[0125] A photosensitive resin composition, characterized by containing the following components (A) to (C),

[0126] (A) component: a base-soluble polymer having an acid equivalent of 100 to 600,

[0127] (B) component: a compound having an ethylenic double bond, and

[0128] (C) component: a photopolymerization initiator

[0129] The aforementioned (A) component contains a copolymer containing 50% by mass or more of styrene units,

[0130] The aforementioned (B) component contains a compound represented by the following general formula (I),

[0131]

[0132] {In the formula, R are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and n1, n2, and n3 are each independently an integer of 0 to 30, provided that the condition n1 + n2 + n3 ≥ 6 is satisfied.}

[0133] The content of the compound represented by the general formula (I) is 5% by mass or more based on the solid content of the aforementioned photosensitive resin composition, and the aforementioned (C) component contains an acridine compound. [2]

[0135] The photosensitive resin composition according to [1], wherein n1, n2, and n3 in the general formula (I) satisfy 20 ≥ n1 + n2 + n3 > 9. [3]

[0137] The photosensitive resin composition according to [1] or [2], wherein all of the Rs in the general formula (I) are hydrogen atoms. [4]

[0139] The photosensitive resin composition according to any one of [1] to [3], wherein the component (B) further contains a pentaerythritol-modified monomer. [5]

[0141] A photosensitive element obtained by laminating a photosensitive resin layer formed from the photosensitive resin composition according to any one of [1] to [4] on a support. [6]

[0143] A method for forming an etching pattern, characterized by comprising:

[0144] A lamination step of laminating the photosensitive resin layer of the photosensitive element according to [5] on a conductor substrate, an exposure step of exposing the laminated photosensitive resin layer, and

[0145] A development step of removing the unexposed portion after the exposure with a developer. [7]

[0147] A method for manufacturing a circuit board, characterized by comprising:

[0148] A lamination step of laminating the photosensitive resin layer of the photosensitive element according to [5] on a conductor substrate, an exposure step of exposing the laminated photosensitive resin layer,

[0149] A development step of removing the unexposed portion after the exposure with a developer,

[0150] A conductor pattern forming step of etching or plating the conductor substrate having an etching pattern formed by the development, and

[0151] A stripping step of stripping the etching pattern.

[0152] <Means for Solving the Third Problem>

[0153] The present inventors have found that the above problems can be solved by the following technical means. The third embodiment of the present invention is as follows. [1]

[0155] A photosensitive resin composition, characterized by comprising:

[0156] (A) Alkali-soluble polymer;

[0157] (B) Compound containing an ethylenically unsaturated bond; and

[0158] (C) Photoinitiator;

[0159] The aforementioned (A) alkali-soluble polymer contains 10% to 24% by mass of structural units of (meth)acrylic acid and 35% to 90% by mass of structural units of styrene based on the total mass of the monomers constituting the aforementioned (A) alkali-soluble polymer, and

[0160] The weight-average molecular weight of the aforementioned (B) compound containing an ethylenically unsaturated bond is 1200 or more. [2]

[0162] The photosensitive resin composition according to [1], wherein the weight-average molecular weight of the aforementioned (B) compound containing an ethylenically unsaturated bond is 1300 or more. [3]

[0164] The photosensitive resin composition according to [1] or [2], wherein 40% by mass or more of the aforementioned (B) compound containing an ethylenically unsaturated bond is an alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the following general formula (II),

[0165]

[0166] {In the formula, R 3 and R 4 each independently represent a hydrogen atom or a methyl group, A is C 2 H 4 , B is C 3 H 6 , n 1 , n 2 , n 3 and n 4 are integers satisfying the relationship of n 1 +n 2 +n 3 +n 4 =2 to 50, and the arrangement of the repeating units of -(A-O)- and -(B-O)- can be random or block, and in the case of block, either -(A-O)- or -(B-O)- is optionally on the biphenyl side}. [4]

[0168] The photosensitive resin composition according to [3], wherein n 1 , n 2 , n 3 and n 4 in the aforementioned general formula (II) satisfy n1 +n 2 +n 3 +n 4 = a relationship of 30 to 50. [5]

[0170] The photosensitive resin composition according to [3], wherein n in the aforementioned general formula (II) 1 , n 2 , n 3 and n 4 satisfy n 1 +n 2 +n 3 +n 4 = a relationship of 2 to 10. [6]

[0172] The photosensitive resin composition according to [1] or [2], wherein the aforementioned (B) ethylenically unsaturated bond-containing compound contains a tri(meth)acrylate compound represented by the following general formula (III),

[0173]

[0174] {In the formula, R 5 , R 6 and R 7 each independently represent a hydrogen atom or a methyl group, X represents an alkylene group having 2 to 6 carbon atoms, m 2 , m 3 and m 4 are each independently an integer of 0 to 40, m 2 +m 3 +m 4 is 1 to 40, and when m 2 +m 3 +m 4 is 2 or more, the plurality of Xs are optionally the same or different from each other}. [7]

[0176] The photosensitive resin composition according to [1] or [2], wherein the aforementioned (B) ethylenically unsaturated bond-containing compound contains a urethane di(meth)acrylate compound represented by the following general formula (IV),

[0177]

[0178] {In the formula, R 8 and R 9 each independently represent a hydrogen atom or a methyl group, Y represents an alkylene group having 2 to 6 carbon atoms, Z represents a divalent organic group, s and t are each independently an integer of 0 to 40, and s + t ≥ 1}. [8]

[0180] The photosensitive resin composition according to any one of [1] to [7], wherein the aforementioned (A) alkali-soluble polymer further contains a structural unit of butyl (meth)acrylate. [9]

[0182] The photosensitive resin composition according to any one of [1] to [8] is used for direct imaging exposure.

[10]

[0184] A method for forming a resist pattern, comprising:

[0185] A lamination step of laminating a photosensitive resin layer formed of the photosensitive resin composition according to any one of [1] to [9] on a support;

[0186] An exposure step of exposing the photosensitive resin layer; and

[0187] A development step of developing the exposed photosensitive resin layer.

[11]

[0189] A method for manufacturing a circuit board, comprising:

[0190] A lamination step of laminating a photosensitive resin layer formed of the photosensitive resin composition according to any one of [1] to [9] on a substrate;

[0191] An exposure step of exposing the photosensitive resin layer;

[0192] A development step of developing the exposed photosensitive resin layer to obtain a substrate with a resist pattern formed thereon;

[0193] A conductor pattern forming step of etching or plating the substrate with the resist pattern formed thereon; and

[0194] A stripping step of stripping the resist pattern.

[0195] <Means for Solving the Fourth Problem>

[0196] The present inventors have found that the above object can be achieved by the following technical means, and have completed the fourth embodiment of the present invention. The fourth embodiment of the present invention is as follows. [1]

[0198] A photosensitive resin composition, comprising:

[0199] (A) An alkali-soluble polymer;

[0200] (B) An olefinically unsaturated bond-containing compound; and

[0201] (C) A photopolymerization initiator;

[0202] The aforementioned (A) alkali-soluble polymer contains a first copolymer in which the content ratio of acid monomer units is less than 25% by mass and the content ratio of aromatic monomer units is 30% by mass or more, and

[0203] the weight average molecular weight of the aforementioned (B) ethylenically unsaturated bond-containing compound is 900 or less. [2]

[0205] The photosensitive resin composition according to [1], wherein the aforementioned (C) photopolymerization initiator contains an acridine compound. [3]

[0207] The photosensitive resin composition according to [1] or [2], wherein the aforementioned (A) alkali-soluble polymer contains a second copolymer in which the content ratio of aromatic monomer units is 45% by mass to 90% by mass. [4]

[0209] The photosensitive resin composition according to any one of [1] to [3], wherein the aforementioned (B) ethylenically unsaturated bond-containing compound contains a tri(meth)acrylate compound represented by the following general formula (III),

[0210]

[0211] {In the formula, R 5 , R 6 and R 7 each independently represent a hydrogen atom or a methyl group, X represents an alkylene group having 2 to 6 carbon atoms, m 2 , m 3 and m 4 each independently are integers from 0 to 40, and when m 2 +m 3 +m 4 is from 0 to 40, and m 2 +m 3 +m 4 is 2 or more, a plurality of Xs are optionally the same or different from each other}. [5]

[0213] The photosensitive resin composition according to any one of [1] to [4], wherein the aforementioned (B) ethylenically unsaturated bond-containing compound contains an alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the following general formula (II),

[0214]

[0215] {In the formula, R 3 and R 4 each independently represent a hydrogen atom or a methyl group, A is C 2 H4 , B is C 3 H 6 , n 1 , n 2 , n 3 and n 4 are integers satisfying the relationship of n 1 +n 2 +n 3 +n 4 = 2 to 50, and the arrangement of the repeating units of -(A-O)- and -(B-O)- can be random or block. In the case of block, either -(A-O)- or -(B-O)- is optionally on the biphenyl side. [6]

[0217] The photosensitive resin composition according to any one of [1] to [5], wherein, as the hindered phenol, it further contains a compound represented by the following general formula (V),

[0218]

[0219] {In the formula, R 51 represents an optionally substituted straight-chain alkyl, branched-chain alkyl, aryl, cyclohexyl, straight-chain alkyl sandwiching a divalent linking group, branched-chain alkyl sandwiching a divalent linking group, cyclohexyl sandwiching a divalent linking group or aryl sandwiching a divalent linking group, and R 52 , R 53 and R 54 each independently represent hydrogen, or an optionally substituted straight-chain alkyl, branched-chain alkyl, aryl, cyclohexyl, straight-chain alkyl sandwiching a divalent linking group, branched-chain alkyl sandwiching a divalent linking group, cyclohexyl sandwiching a divalent linking group or aryl sandwiching a divalent linking group.}. [7]

[0221] The photosensitive resin composition according to any one of [1] to [6] is used for direct imaging exposure. [8]

[0223] A photosensitive element obtained by laminating a photosensitive resin layer formed from the photosensitive resin composition according to any one of [1] to [7] on a support. [9]

[0225] A method for forming an anti-etching pattern, which includes:

[0226] A lamination step of laminating the aforementioned photosensitive resin layer of the photosensitive element described in [8] on a conductor substrate;

[0227] An exposure step of exposing the laminated aforementioned photosensitive resin layer; and

[0228] A developing step of developing the aforementioned photosensitive resin layer that has been exposed.

[10]

[0230] A method for manufacturing a circuit board, comprising:

[0231] A lamination step of laminating the aforementioned photosensitive resin layer of the photosensitive element described in [8] on a conductor substrate;

[0232] An exposure step of exposing the laminated aforementioned photosensitive resin layer;

[0233] A developing step of developing the exposed aforementioned photosensitive resin layer to form an etching resist pattern on the aforementioned conductor substrate;

[0234] A conductor pattern forming step of etching or plating the aforementioned conductor substrate on which the aforementioned etching resist pattern has been formed; and

[0235] A stripping step of stripping the aforementioned etching resist pattern.

[0236] Effects of the Invention

[0237] <Effect of the First Embodiment>

[0238] According to the first embodiment of the present invention, there is provided an etching resist material that suppresses the aspect ratio difference of the wiring width when forming a fine conductor pattern by a production line.

[0239] <Effect of the Second Embodiment>

[0240] According to the second embodiment of the present invention, there is provided a novel photosensitive material that has high levels of properties such as sensitivity and resolution typically required for photosensitive materials, and is excellent in both developing dispersibility and adhesion of fine patterns.

[0241] <Effect of the Third Embodiment>

[0242] According to the third embodiment of the present invention, there is provided a photosensitive resin composition that can balance the hole covering property of the etching resist pattern and the suppression of water residue short-circuit failures.

[0243] <Effect of the Fourth Embodiment>

[0244] According to the fourth embodiment of the present invention, there is provided a photosensitive resin composition that can ensure good resolution of the etching resist pattern and extend the minimum developing time, and a method for forming an etching resist pattern or a circuit board using the same. Detailed Embodiments

[0245] <First Embodiment>

[0246] Hereinafter, a method for implementing the first embodiment of the present invention (hereinafter simply referred to as "this first embodiment") will be specifically described.

[0247] <Photosensitive Resin Composition>

[0248] In this first embodiment, the photosensitive resin composition contains the following components (A) to (C).

[0249] Component (A): An alkali-soluble polymer

[0250] Component (B): A compound having an ethylenic double bond, and

[0251] Component (C): A photoinitiator.

[0252] [Component (A): Alkali-soluble polymer]

[0253] The above-mentioned component (A) is not particularly limited as long as it is soluble in the developer described later. It is preferably a copolymer of (meth)acrylic acid and other monomers. The dispersity of the copolymer represented by the ratio of the weight average molecular weight (described later) to the number average molecular weight of the copolymer is preferably 1 or more and 6 or less.

[0254] Examples of (meth)acrylic acid include (meth)acrylic acid, pentenoic acid, unsaturated dicarboxylic anhydride, hydroxystyrene, etc. Examples of the above-mentioned unsaturated dicarboxylic anhydride include maleic anhydride, itaconic anhydride, fumaric acid, citraconic anhydride, etc. Among them, (meth)acrylic acid is preferred.

[0255] As the copolymerization ratio of the (meth)acrylic acid unit in the above-mentioned component (A), relative to the total mass of all monomer units, it is preferably 10% by mass to 24% by mass, more preferably 15% by mass to 23% by mass. When the content ratio of the (meth)acrylic acid unit is within this range, it is preferred from the viewpoints of suppressing the etching rate when forming a conductor pattern (maintaining the bottom width of the above-mentioned conductor line pattern at a certain value or more) and suppressing the aspect ratio difference of the wiring width.

[0256] Examples of other monomers include unsaturated aromatic compounds (sometimes also referred to as "aromatic monomers"), (meth)acrylic acid alkyl esters, (meth)acrylic acid aralkyl esters, conjugated diene compounds, polar monomers, crosslinkable monomers, etc.

[0257] Examples of unsaturated aromatic compounds include styrene, α-methylstyrene, vinylnaphthalene, etc. Among them, styrene is preferred.

[0258] (Meth)acrylic acid alkyl esters are a concept that includes both linear alkyl esters and cyclic alkyl esters. Specifically, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, n-tetradecyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, etc. can be cited.

[0259] Separately, as aralkyl (meth)acrylates, for example, benzyl (meth)acrylate, etc. can be cited;

[0260] As conjugated diene compounds, for example, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 2-phenyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, etc. can be cited.

[0261] As polar monomers, for example, the following can be cited:

[0262] Hydroxyl group-containing monomers such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, pentenol, etc.;

[0263] Amino group-containing monomers such as 2-aminoethyl methacrylate, etc.;

[0264] Amide group-containing monomers such as (meth)acrylamide, N-hydroxymethyl (meth)acrylamide, etc.;

[0265] Cyano group-containing monomers such as acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-cyanoethyl acrylate, etc.;

[0266] Epoxy group-containing monomers such as glycidyl (meth)acrylate, 3,4-epoxycyclohexyl (meth)acrylate, etc.;

[0267] etc.

[0268] As crosslinkable monomers, for example, trimethylolpropane triacrylate, divinylbenzene, etc. can be cited.

[0269] As the aforementioned component (A), a copolymer of (meth)acrylic acid, styrene and other monomers is particularly preferred.

[0270] As the copolymerization ratio of the styrene unit in the aforementioned component (A), it is preferably 32% by mass or more, more preferably 35% by mass or more, based on the total mass of all monomer units. In addition, as the copolymerization ratio of the styrene unit in the aforementioned component (A), it is preferably 60% by mass or less, more preferably 55% by mass or less, based on the total mass of all monomer units. When setting the copolymerization ratio of styrene, which has high hydrophobicity and is difficult to be compatible with the developer and the development cleaning water, within the above range, it is preferable from the viewpoint of suppressing the aspect ratio difference of the wiring width.

[0271] The weight-average molecular weight of the aforementioned component (A) (when the component (A) contains a plurality of copolymers, it is the weight-average molecular weight of the entire mixture) is preferably 5,000 to 1,000,000, more preferably 10,000 to 500,000, and further preferably 15,000 to 100,000. When adjusting the weight-average molecular weight of the component (A) within this range, it is preferable from the viewpoint of making the development time during the formation of the resist pattern suitable for the operating state of the production line used.

[0272] In this first embodiment, the content of the component (A) in the photosensitive resin composition is preferably 10% by mass to 90% by mass, more preferably 20% by mass to 80% by mass, and further preferably 40% by mass to 60% by mass, based on the total solid content of the photosensitive resin composition (hereinafter, the same applies to each contained component without special mention). This content is preferably 10% by mass or more from the viewpoint of maintaining alkali developability, and on the other hand, is preferably 90% by mass or less from the viewpoint of enabling the resist pattern formed by exposure to fully exhibit the performance as a resist.

[0273] The copolymer in which the content ratio of the (meth)acrylic acid unit is 10% by mass to 24% by mass and the content ratio of the styrene unit is 32% by mass to 60% is preferably 8% or more, more preferably 10% or more, and particularly preferably 13.5 / 99.19×100% by mass or more, based on the total solid content of the photosensitive resin composition. The copolymer in which the content ratio of the (meth)acrylic acid unit is 10% by mass to 24% by mass and the content ratio of the styrene unit is 32% by mass to 60% can be 50% by mass or less, can be 40% by mass or less, can be 30% by mass or less, can be 27 / 99.19×100% by mass or less, and can be 20% by mass or less, based on the total solid content of the photosensitive resin composition.

[0274] [Component (B): Compound having an ethylenic double bond]

[0275] It is sufficient that the component (B) has one or more ethylenic double bonds. A compound having two or more ethylenic double bonds is preferably used.

[0276] As the (B) compound having two ethylenic double bonds, for example, a bisphenol A compound is preferably used, particularly a di(meth)acrylate of a polyalkylene glycol obtained by adding an average of 2 to 15 moles of an alkylene oxide to each end of bisphenol A, etc.

[0277] In addition, as the (B) compound having three ethylenic double bonds, for example, a trimethylolpropane compound is preferably used, particularly a tri(meth)acrylate of a polyalkylene triol obtained by adding an average of 3 to 25 moles of an alkylene oxide to trimethylolpropane, etc.

[0278] Furthermore, as the (B) compound having four ethylenic double bonds, for example, a pentaerythritol compound is preferably used, particularly a tetra(meth)acrylate of a polyol obtained by adding an average of 4 to 35 moles of an alkylene oxide to pentaerythritol, etc.

[0279] As commercially available products thereof, for example, “BPE-500”, “A-TMPT-3EO”, “A-9300-1CL”, etc. (all of the above are manufactured by Shin-Nakamura Chemical Co., Ltd.) can be cited:

[0280] “ARONIX M-327”, etc. (manufactured by Toagosei Co., Ltd.), etc.

[0281] The content of the (B) component in the photosensitive resin composition of this first embodiment is preferably 1% by mass to 70% by mass, more preferably 5% by mass to 60% by mass, and still more preferably 10% by mass to 50% by mass. From the viewpoint of suppressing curing defects and delaying the development time, this content is preferably 1% by mass or more. On the other hand, from the viewpoint of suppressing cold flow and delaying the peeling of the cured resist, it is preferably 70% by mass or less.

[0282] As the (B) component, a high molecular weight compound having a molecular weight of 1000 or more is preferably used. The molecular weight of this high molecular weight compound is more preferably 1300 or more and 3000 or less. When containing such a high molecular weight compound, it is preferable from the viewpoints of suppressing the etching rate and the aspect ratio difference of the wiring width when forming a conductor pattern.

[0283] It should be noted that the proportion of such a high molecular weight compound in the (B) component is preferably set to 20% by mass or more, more preferably 20 to 50% by mass.

[0284] Here, as an index of the double bond concentration of the (B) component, the DD value is defined. The DD value is the number of double bonds relative to the weight average molecular weight of the monomer, and each monomer has a unique value.

[0285] When a monomer having a small DD value is used in the photosensitive resin composition, the film after photocuring tends to become soft.

[0286] When the (B) component is composed of multiple components, the weighted average of the DD values of each ethylenically unsaturated bond-containing compound and the compounding ratio is regarded as the DD value of the composition.

[0287] From the viewpoints of suppressing the aspect ratio difference of the wiring width and improving the hole covering property, the preferred range of the DD value of the composition is 0.10 to 0.13. More preferably, it is 0.10 to 0.125.

[0288] [(C) component: Photoinitiator]

[0289] (C) component is a component that generates radicals capable of initiating the polymerization of the aforementioned (B) component upon irradiation with light.

[0290] Examples of such (C) components include aromatic ketone compounds, quinone compounds, benzoin ether compounds, benzoin compounds, benzil compounds, hexaarylbiimidazole compounds, acridine compounds, and the like.

[0291] Among them, from the viewpoints of high resolution and good hole covering property, acridine compounds are preferably used.

[0292] The content of the acridine compound in the photosensitive resin composition of this first embodiment is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, more preferably 0.2% by mass, more preferably 0.3% by mass, more preferably 0.4% by mass.

[0293] The content of the acridine compound in the photosensitive resin composition of this first embodiment is preferably 2.0% by mass or less, more preferably 1.8% by mass or less, more preferably 1.7% by mass or less, more preferably 1.6% by mass or less. If it is within the above range, an etching resist material capable of suppressing the aspect ratio difference of the wiring width can be provided, which is preferable.

[0294] Examples of the acridine compound include acridine, 9-phenylacridine, 1,6-bis(9-acridinyl)hexane, 1,7-bis(9-acridinyl)heptane, 1,8-bis(9-acridinyl)octane, 1,9-bis(9-acridinyl)nonane, 1,10-bis(9-acridinyl)decane, 1,11-bis(9-acridinyl)undecane, 1,12-bis(9-acridinyl)dodecane, and the like.

[0295] As the (C) component, acridine compounds and hexaarylbiimidazole compounds are preferably used.

[0296] Examples of the above-mentioned hexaarylbiimidazole compound include 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2,2',5-tris-(o-chlorophenyl)-4-(3,4-dimethoxyphenyl)-4',5'-diphenylimidazole dimer, 2,4-bis-(o-chlorophenyl)-5-(3,4-dimethoxyphenyl)-diphenylimidazole dimer, 2,4,5-tris-(o-chlorophenyl)-diphenylimidazole dimer, 2-(o-chlorophenyl)-bis-4,5-(3,4-dimethoxyphenyl)-imidazole dimer, 2,2'-bis-(2-fluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,3-difluoromethylphenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,4-difluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,5-difluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,6-difluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,3,4-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,3,5-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,3,6-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,4,5-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,4,6-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,3,4,5-tetrafluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,3,4,6-tetrafluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, 2,2'-bis-(2,3,4,5,6-pentafluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-imidazole dimer, and the like.

[0297] The content of the component (C) in the photosensitive resin composition of the first embodiment is preferably in the range of 0.1% by mass to 2% by mass, more preferably in the range of 0.2% by mass to 1.8% by mass, still more preferably in the range of 0.3% by mass to 1.7% by mass, and particularly preferably in the range of 0.4% by mass to 1.6% by mass. When the content of the component (C) is set within such a range, it is preferable from the viewpoint of obtaining good sensitivity and peeling characteristics.

[0298] From the viewpoint of improving sensitivity and resolution, the component (C) may further contain a sensitizer. Examples of such a sensitizer include N-aryl amino acids, organic halogen compounds, and other sensitizers.

[0299] Specifically, examples of the above N-aryl amino acids include N-phenylglycine, N-methyl-N-phenylglycine, N-ethyl-N-phenylglycine, etc.;

[0300] Examples of the organic halogen compounds include amyl bromide, isoamyl bromide, isobutene bromide, vinyl bromide, diphenylmethyl bromide, benzyl bromide, dibromomethane, tribromomethyl phenyl sulfone, carbon tetrabromide, tris(2,3-dibromopropyl) phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, chlorotriazine compounds, etc.

[0301] Examples of the above other sensitizers include quinone compounds such as 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, 3-chloro-2-methylanthraquinone, etc.;

[0302] aromatic ketone compounds such as benzophenone, Michler's ketone [4,4'-bis(dimethylamino)benzophenone], 4,4'-bis(diethylamino)benzophenone, etc.;

[0303] benzoin ether compounds such as benzoin, benzoin ethyl ether, benzoin phenyl ether, methyl benzoin, ethyl benzoin, etc.;

[0304] oxime ester compounds such as benzil dimethyl ketal, benzil diethyl ketal, 1-phenyl-1,2-propanedione-2-O-benzoyl oxime, 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime, etc.;

[0305] and so on.

[0306] The content of the sensitizer in this first embodiment is preferably 0.01% by mass to 5% by mass, more preferably 0.05% by mass to 3% by mass, and still more preferably 0.1% by mass to 2% by mass from the viewpoints of the sensitivity of the composition and the peelability of the resist cured film.

[0307] It should be noted that in the photosensitive resin composition of this first embodiment, when an acridine compound and an N-aryl amino acid are used as the component (C) and combined within the above-mentioned use ratio range, it is preferable from the viewpoints of suppressing the etching rate when forming a conductor pattern and suppressing the aspect ratio difference of the wiring width.

[0308] [Other components]

[0309] In addition to the components (A) to (C) described above, the photosensitive resin composition of this first embodiment may further contain other components. Examples of such other components include leuco dyes, basic dyes, plasticizers, antioxidants, stabilizers, free radical polymerization inhibitors, solvents, and the like.

[0310] [Leuco dye]

[0311] The above leuco dye may be incorporated into the photosensitive resin composition of this first embodiment in order to impart suitable color development properties and excellent stripping properties to the resist cured film.

[0312] Specific examples of the leuco dye include, for example, leuco crystal violet (tris[4-(dimethylamino)phenyl]methane), 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide, 3-(4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)phthalide, 3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide, 1,3-dimethyl-6-diethylaminofluoran, 2-chloro-3-methyl-6-dimethylaminofluoran, 3-dibutylamino-6-methyl-7-anilinofluoran, 3-diethylamino-6-methyl-7-anilinofluoran, 3-diethylamino-6-methyl-7-xylidinofluoran, 2-(2-chloroanilino)-6-dibutylaminofluoran, 3,6-dimethoxyfluoran, 3,6-din-butoxyfluoran, 1,2-benzofluoran-6-diethylamino, 1,2-benzofluoran-6-dibutylamino, 1,2-benzofluoran-6-ethylisoamylamino, 2-methyl-6-(N-p-tolyl-N-ethylamino)fluoran, 2-(N-phenyl-N-methylamino)-6-(N-p-tolyl-N-ethylamino)fluoran, 2-(3'-trifluoromethylanilino)-6-diethylaminofluoran, 3-chloro-6-cyclohexylamino-fluoran, 2-methyl-6-cyclohexylamino-fluoran, 3-methoxy-4-dodecyloxystyrylquinoline, and the like. Among them, leuco crystal violet is preferred.

[0313] The content of the leuco dye in the photosensitive resin composition of this first embodiment is preferably 0.6% by mass to 1.6% by mass, more preferably 0.7% by mass to 1.2% by mass. By setting the use ratio of the leuco dye within this range, good color development properties and good stripping properties can be achieved.

[0314] [Basic dye]

[0315] As the basic dye described above, for example, basic green 1 [CAS number (the same applies hereinafter): 633-03-4] (for example, Aizen Diamond Green GH, trade name, manufactured by Hodogaya Chemical Co., Ltd.), malachite green oxalate [2437-29-8] (for example, Aizen Malachite Green, trade name, manufactured by Hodogaya Chemical Co., Ltd.), brilliant green [633-03-4], magenta [632-99-5], methyl violet [603-47-4], methyl violet 2B [8004-87-3], crystal violet [548-62-9], methyl green [82-94-0], victoria blue B [2580-56-5], basic blue 7 [2390-60-5] (for example, Aizen Victoria Pure Blue BOH, trade name, manufactured by Hodogaya Chemical Co., Ltd.), rhodamine B [81-88-9], rhodamine 6G [989-38-8], basic yellow 2 [2465-27-2], diamond green, etc. Among them, one or more selected from basic green 1, malachite green oxalate, basic blue 7, and diamond green are preferred, and basic green 1 is particularly preferred from the viewpoints of hue stability and exposure contrast.

[0316] The content of the basic dye in the photosensitive resin composition of this first embodiment is preferably in the range of 0.001% by mass to 3% by mass, more preferably in the range of 0.01% by mass to 2% by mass, and further preferably in the range of 0.01% by mass to 1.2% by mass. By setting the usage ratio within this range, good color development and high sensitivity can be achieved simultaneously.

[0317] [Solvent]

[0318] The photosensitive resin composition of this first embodiment can be a mixture of the above components (A) to (C) and optionally used other components, or can be used in the form of a photosensitive resin composition preparation liquid formed by adding an appropriate solvent to these components.

[0319] Examples of the solvent used herein include:

[0320] Ketone compounds such as methyl ethyl ketone (MEK);

[0321] Alcohols such as ethanol, ethanol, and isopropyl alcohol;

[0322] etc.

[0323] As the usage ratio of the solvent, it is preferably set to a ratio such that the viscosity of the photosensitive resin composition preparation liquid at 25°C is 500 to 4000 mPa·sec.

[0324] <Photosensitive element>

[0325] In this first embodiment, the photosensitive element is a laminate (photosensitive resin laminate) formed by laminating a photosensitive resin layer formed from the above photosensitive resin composition on a support. Optionally, a protective layer may be provided on the surface of the photosensitive resin layer opposite to the support.

[0326] [Support]

[0327] As the support, a transparent substrate that transmits light emitted from the self-exposure light source is preferred. Examples of such a support include polyethylene terephthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, polymethyl methacrylate copolymer film, polystyrene film, polyacrylonitrile film, styrene copolymer film, polyamide film, cellulose derivative film, etc. As these films, stretched films may be used as needed.

[0328] The haze of the support is preferably 5 or less.

[0329] When the thickness of the support is thin, it is advantageous in terms of image formability and economy, but the strength needs to be maintained. Considering both, a support with a thickness of 10 μm to 30 μm can be preferably used.

[0330] [Photosensitive resin composition layer]

[0331] When the photosensitive resin composition used in the formation of the photosensitive resin composition layer contains a solvent, it is preferred that the solvent has been removed from the photosensitive resin composition layer, but the residual solvent is also acceptable.

[0332] The thickness of the photosensitive resin composition layer is preferably 5 μm to 100 μm, more preferably 7 μm to 60 μm. The thinner the thickness, the higher the resolution, and the thicker the thickness, the higher the film strength. Therefore, the thickness of this composition layer can be appropriately adjusted within the above range according to the use.

[0333] [Protective layer]

[0334] An important characteristic of the protective layer is that the adhesion to the photosensitive resin composition layer is sufficiently less than the adhesion between the support and the photosensitive resin composition layer, and it can be easily peeled off. As the protective layer, for example, polyethylene film, polypropylene film, etc. can be preferably used. In addition, films with excellent peelability disclosed in, for example, Japanese Patent Laid-Open No. 59-202457 can be used.

[0335] The thickness of the protective layer is preferably 10 μm to 100 μm, more preferably 10 μm to 50 μm.

[0336] [Method for manufacturing a photosensitive element]

[0337] The photosensitive element can be manufactured by successively laminating a support, a photosensitive resin layer, and, if necessary, a protective layer. As the lamination method of the support, the photosensitive resin layer, and the protective layer, a known method can be adopted.

[0338] For example, the photosensitive resin composition is prepared into the aforementioned photosensitive resin composition preparation liquid. First, it is coated on the support using a bar coater or a roll coater and dried to form a photosensitive resin composition layer formed of the photosensitive resin composition on the support. Then, if necessary, a protective layer is laminated on the formed photosensitive resin composition layer, thereby enabling the manufacture of the photosensitive element.

[0339] <Method for forming an etching pattern>

[0340] The above-mentioned photosensitive element can be used to form an etching pattern on a substrate.

[0341] The method for forming an etching pattern preferably successively includes the following steps:

[0342] A lamination step of laminating the photosensitive resin layer of the photosensitive element on a conductor substrate,

[0343] An exposure step of exposing the laminated photosensitive resin composition layer, and

[0344] A development step of removing the unexposed portion after the aforementioned exposure with a developer.

[0345] In addition, the lamination step is preferably a step of laminating the photosensitive resin layer of the photosensitive element on the conductor substrate with a wetting agent interposed therebetween. As the wetting agent, it is preferably composed of one or more selected from pure water, deionized water, and electrolyzed water, and a copper chelating agent (for example, one or more compounds selected from the group consisting of imidazole compounds, triazole compounds, pyridine compounds, and pyrazole compounds).

[0346] In the method for forming an etching pattern of this first embodiment, first, in the lamination step, a photosensitive resin composition layer is formed on a substrate using a laminator. Specifically, when the photosensitive element has a protective layer, after peeling off the protective layer, the photosensitive resin composition layer is heat-pressed on the substrate surface using a laminator for lamination.

[0347] As the substrate, a metal plate or an insulating substrate having a metal film is used. As the material of the metal, for example, copper, stainless steel (SUS), glass, indium tin oxide (ITO), etc. can be cited. These substrates may also have through holes for coping with multilayer substrates.

[0348] Here, the photosensitive resin composition layer may be laminated only on one side of the substrate surface, or may be laminated on both sides of the substrate as required. The heating temperature at this time is preferably set to 40°C to 160°C. From the viewpoint of further improving the adhesion of the obtained anti-etching pattern to the substrate, it is preferred to perform the heating and pressing bonding twice or more. When performing the pressing bonding twice or more, a two-stage laminator with two rollers may be used, or the laminate of the substrate and the photosensitive resin composition layer may be repeatedly pressed by rollers several times.

[0349] Next, in the exposure step, the photosensitive resin composition layer is exposed using an exposure machine. The exposure may be performed through the support without peeling the support, or may be performed after peeling the support as necessary.

[0350] By performing this exposure in a pattern, after the development process described later, a resist film (resist pattern) having a desired pattern can be obtained. The patterned exposure can be performed by any method of exposure through a photomask and maskless exposure. When the exposure is performed through a photomask, the exposure amount is determined by the light source illumination and the exposure time. The exposure amount can be measured using a light meter.

[0351] In maskless exposure, exposure is performed on the substrate using a direct drawing device without using a photomask. As the light source, a semiconductor laser with a wavelength of 350nm to 410nm, an ultra-high pressure mercury lamp, etc. are used. In maskless exposure, the drawing pattern is controlled by a computer, and the exposure amount is determined by the illumination of the exposure light source and the moving speed of the substrate.

[0352] Next, in the development step, the unexposed portion of the photosensitive resin composition layer is removed with a developer. After exposure, when a support is present on the photosensitive resin composition layer, it is preferably removed before subjecting the layer to the development step.

[0353] In the development step, a developer formed of an alkaline aqueous solution is used to develop and remove the unexposed portion to obtain a resist image. As the alkaline aqueous solution, for example, Na 2 CO 3 , K 2 CO 3 The alkaline aqueous solution is selected according to the characteristics of the photosensitive resin composition layer, and preferably uses a concentration of 0.2 mass % to 2 mass % of Na 2 CO 3 Aqueous solution. The alkaline aqueous solution may also contain a surfactant, a defoaming agent, a small amount of an organic solvent for accelerating development, and the like.

[0354] The temperature of the developer in the development step is preferably maintained at a constant temperature within a range of 20°C to 40°C.

[0355] An etch resist pattern is obtained through the above-described processes. Depending on the circumstances, a heating process at 100°C to 300°C may be further performed. Performing this heating process is appropriate from the viewpoint of further improving chemical resistance. Heating can be carried out using a heating furnace in a suitable manner such as hot air, infrared rays, far-infrared rays, etc.

[0356] <Method for forming a circuit board>

[0357] The method for forming a circuit board according to this first embodiment preferably sequentially includes the following processes:

[0358] A lamination process of laminating a photosensitive resin composition of a photosensitive element layer by layer on a conductor substrate,

[0359] An exposure process of exposing the laminated photosensitive resin composition layer,

[0360] A development process of removing the unexposed portion after the above exposure with a developer,

[0361] A conductor pattern formation process of etching or plating the conductor substrate having an etch resist pattern formed thereon through the above development, and

[0362] A stripping process of stripping the above etch resist pattern.

[0363] In addition, the lamination process is preferably a process of laminating a photosensitive resin layer of a photosensitive element on a conductor substrate with a wetting agent interposed therebetween. As the wetting agent, it is preferably composed of one or more selected from pure water, deionized water, and electrolyzed water, and a copper chelating agent (for example, one or more compounds selected from the group consisting of imidazole compounds, triazole compounds, pyridine compounds, and pyrazole compounds).

[0364] In the conductor pattern formation process, a conductor pattern can be formed on the substrate surface (such as a copper surface) exposed through the development process on the substrate having an etch resist pattern formed thereon using a known etching method or plating method.

[0365] In the above stripping process, the substrate having a conductor pattern formed thereon is brought into contact with an appropriate stripping solution to strip and remove the etch resist pattern. Through this process, a desired circuit board is obtained.

[0366] The stripping solution used in the stripping process is preferably an aqueous alkali solution. As this aqueous alkali solution, for example, a 2% to 5% by mass NaOH aqueous solution or KOH aqueous solution is preferably used. A small amount of a water-soluble solvent such as alcohol can be added to the stripping solution. The temperature of the stripping solution in the stripping process is preferably set to 40°C to 70°C.

[0367] Generally, in the formation of conductor patterns based on etching, regardless of the etching speed, the etching time to achieve a desired wiring width can be adjusted by, for example, adjusting the conveyance speed of the etching line. However, when the etching speed is too fast, the conveyance speed also becomes too fast, sometimes causing problems such as being unable to set the etching time in practical applications.

[0368] Moreover, in recent years, the manufacturing of circuit boards is usually carried out by a production line that conveys the substrate along a fixed direction at the edge and processes it sequentially. There are cases where the lines of the conductors are parallel (lines in the MD direction), perpendicular (lines in the TD direction), and skewed with respect to the conveyance direction of the substrate. Especially when the etching speed is fast, there is a tendency for the aspect ratio difference of the wiring width to become more obvious.

[0369] The inventors of the present invention conducted in-depth research and found that when the photosensitive resin composition for forming a cured resist pattern has specific physical properties, it is possible to provide a resist material that suppresses the aspect ratio difference of the wiring width when forming a fine conductor pattern by a production line.

[0370] That is, the photosensitive resin composition of the first embodiment of the present invention has the following characteristics: a photosensitive resin layer formed from the aforementioned photosensitive resin composition is laminated with a thickness of 25 μm on a copper-clad laminate having a copper foil with a thickness of 18 μm, and after being subjected to pattern-like light irradiation with a line / space = 50 μm / 30 μm and development treatment to form a cured resist pattern, the bottom width of the copper wire pattern obtained after removing the aforementioned cured resist pattern after performing a copper etching treatment at 50°C for 55 seconds is 38 μm or more (preferably 38 μm to 50 μm, more preferably 40 μm to 45 μm).

[0371] The resist pattern swells / shrinks in each of the development, water washing, and etching processes. In particular, the swelling / shrinking in the water washing process is large. It is considered that the swelling / shrinking of this resist pattern reduces the adhesion between the wiring and the resist pattern. It is considered that the resist pattern formed from the photosensitive resin composition of the first embodiment of the present invention swells / shrinks little in any of the development, water washing, and etching processes, and it is difficult for etching to proceed at the interface between the resist pattern and the wiring, and the aspect ratio difference of the wiring width can be suppressed.

[0372] In the first embodiment of the present invention, a specific photosensitive resin composition is distinguished as a means for achieving the invention effect by focusing on the characteristics (the bottom width of the conductor line width is a certain value or more) when using a specific analysis method (specific etching conditions).

[0373] It should be noted that the adjustment of the bottom width of the conductor line width can be carried out by appropriately setting the composition of the photosensitive resin composition.

[0374] In addition, the conductor pattern (wiring) formed by the method for forming a circuit board according to the first embodiment as described above can make the aspect ratio of the wiring width of the conductor pattern extremely small. The aspect ratio of the wiring width is a quantity represented by the difference between the wiring width (TD) of the conductor line in the TD direction and the wiring width (MD) of the conductor line in the MD direction, TD - MD.

[0375] The absolute value of the aspect ratio of the wiring width in the conductor pattern formed by the method for forming a conductor pattern according to the first embodiment is preferably 0 μm to 5 μm, more preferably 0 μm to 3 μm.

[0376] The photosensitive resin composition, photosensitive element, and method for forming a circuit board according to the first embodiment can be extremely suitable for manufacturing, for example, printed circuit boards, lead frames, substrates having uneven patterns, semiconductor packages, and the like.

[0377] It should be noted that, regarding the measurement methods of the above various parameters, in the case of no special description, they are measured according to the measurement methods in the examples described later.

[0378] <Second Embodiment>

[0379] Hereinafter, a mode for implementing the second embodiment of the present invention (hereinafter simply referred to as "the second embodiment of the present invention") will be specifically described.

[0380] <Photosensitive Resin Composition>

[0381] In the second embodiment of the present invention, the photosensitive resin composition contains the following components (A) to (C).

[0382] Component (A): an alkali-soluble polymer having an acid equivalent of 100 to 600.

[0383] Component (B): a compound having an ethylenic double bond, and

[0384] Component (C): a photopolymerization initiator.

[0385] [Component (A): Alkali-soluble Polymer]

[0386] The acid equivalent of the aforementioned component (A) is 100 to 600 (preferably 200 to 500, more preferably 250 to 450), and contains a copolymer containing 50% by mass or more of styrene units. Here, in the present specification, the styrene unit refers to substituted or unsubstituted styrene. It should be noted that, as the substituent, there is no particular limitation, and examples thereof include an alkyl group, a halogen group, a hydroxyl group, and the like.

[0387] Component (A) is a copolymer of a styrene derivative and other monomers such as an acid monomer.

[0388] As the acid monomer, for example, (meth)acrylic acid, pentenoic acid, unsaturated dicarboxylic anhydride, hydroxystyrene, etc. can be cited. As the unsaturated dicarboxylic anhydride, for example, maleic anhydride, itaconic anhydride, fumaric acid, citraconic anhydride, etc. can be cited. Among them, (meth)acrylic acid is preferred.

[0389] As other monomers, for example, unsaturated aromatic compounds (sometimes also referred to as "aromatic monomers"), (meth)acrylic acid alkyl esters, (meth)acrylic acid aralkyl esters, conjugated diene compounds, polar monomers, crosslinkable monomers, etc. can be cited.

[0390] As the unsaturated aromatic compound, for example, vinylnaphthalene, etc. can be cited.

[0391] (Meth)acrylic acid alkyl ester is a concept including both linear alkyl esters and cyclic alkyl esters. Specifically, for example, (meth)acrylic acid methyl ester, (meth)acrylic acid ethyl ester, (meth)acrylic acid n-propyl ester, (meth)acrylic acid isopropyl ester, (meth)acrylic acid n-butyl ester, (meth)acrylic acid tert-butyl ester, (meth)acrylic acid pentyl ester, (meth)acrylic acid hexyl ester, (meth)acrylic acid heptyl ester, (meth)acrylic acid octyl ester, (meth)acrylic acid 2-ethylhexyl ester, (meth)acrylic acid nonyl ester, (meth)acrylic acid decyl ester, (meth)acrylic acid lauryl ester, (meth)acrylic acid n-tetradecyl ester, (meth)acrylic acid stearyl ester, (meth)acrylic acid cyclohexyl ester, etc. can be cited.

[0392] Respectively, as the (meth)acrylic acid aralkyl ester, for example, (meth)acrylic acid benzyl ester, etc. can be cited;

[0393] As the conjugated diene compound, for example, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 2-phenyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, etc. can be cited.

[0394] As the polar monomer, for example,

[0395] (Meth)acrylic acid hydroxyethyl ester, (meth)acrylic acid hydroxypropyl ester, (meth)acrylic acid hydroxybutyl ester, pentenol and other hydroxyl-containing monomers;

[0396] 2-aminoethyl methacrylate and other amino-containing monomers;

[0397] (Meth)acrylamide, N-hydroxymethyl(meth)acrylamide and other amide group-containing monomers;

[0398] Acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-cyanoethyl acrylate and other cyano group-containing monomers;

[0399] Glycidyl (meth)acrylate, 3,4-epoxycyclohexyl (meth)acrylate and other epoxy group-containing monomers;

[0400] etc.

[0401] As crosslinkable monomers, for example, trimethylolpropane triacrylate, divinylbenzene, etc. can be cited.

[0402] The aforementioned component (A) is particularly preferably a copolymer of (meth)acrylic acid, styrene, and other monomers.

[0403] Component (A) contains copolymer 1 containing 50% by mass or more of styrene units. The amount of styrene units in copolymer 1 is preferably 50% to 80% by mass, more preferably 51% to 70% by mass.

[0404] In the second embodiment, component (A) may consist only of copolymer 1 or may be a mixture of copolymer 1 and other polymers. The content of copolymer 1 in component (A) is preferably 5% to 90% by mass, more preferably 10% to 80% by mass, and further preferably 20% to 70% by mass.

[0405] As other polymers, a copolymer of the acid monomer described above and other monomers and a substance that does not belong to copolymer 1 (copolymer 2) is suitable.

[0406] The weight average molecular weight of component (A) (when component (A) contains a plurality of copolymers, the weight average molecular weight of the whole mixture) is preferably 5,000 to 1,000,000, more preferably 10,000 to 500,000, and further preferably 15,000 to 100,000. When the weight average molecular weight of component (A) is adjusted within this range, it is preferable from the viewpoint of making the development time during the formation of the resist pattern suitable for the operating state of the production line used. The dispersity of the copolymer represented by the ratio of the weight average molecular weight to the number average molecular weight of component (A) is preferably 1 or more and 6 or less.

[0407] In the second embodiment, the content of component (A) in the photosensitive resin composition is preferably 10% to 90% by mass, more preferably 20% to 80% by mass, and further preferably 40% to 60% by mass based on the total solid content of the photosensitive resin composition (hereinafter, for each contained component, it is the same in the absence of special instructions). This content is preferably 10% by mass or more from the viewpoint of maintaining alkali developability, and on the other hand, is preferably 90% by mass or less from the viewpoint of allowing the resist pattern formed by exposure to fully exhibit the performance as a resist.

[0408] [Component (B): Compound having an ethylenic double bond]

[0409] (B) The component is not particularly limited as long as it has one or more ethylenic double bonds. Among them, the component (B) in this second embodiment contains a compound represented by the following general formula (I) as an essential compound (B1).

[0410]

[0411] {In the formula, R are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and n1, n2, and n3 are each independently an integer of 0 to 30, provided that the condition n1 + n2 + n3 ≥ 6 is satisfied.}

[0412] In formula (I), as R, each is independently preferably a hydrogen atom or a methyl group, more preferably a hydrogen atom. n1, n2, and n3 are each independently preferably an integer of 1 to 30, more preferably an integer of 3 to 21.

[0413] In formula (I), from the viewpoint of improving the development dispersibility, the value of n1 + n2 + n3 is preferably more than 9 and 20 or less, more preferably 15 or more and 20 or less.

[0414] In formula (I), from the viewpoint of improving the development dispersibility, it is preferred that at least one R is a hydrogen atom, more preferably all Rs are hydrogen atoms.

[0415] Furthermore, in formula (I), from the viewpoint of balancing the development dispersibility and the adhesion, it is particularly preferred that all Rs are hydrogen atoms and the value of n1 + n2 + n3 is 15 or more and 20 or less.

[0416] The compound represented by formula (I) is synthesized by a known method. For example, an adduct obtained by adding 6 equivalents or more of ethylene oxide to trimethylolpropane is further added with 3 moles of (meth)acrylic acid or transesterified to obtain it.

[0417] As a preferred specific example of the compound represented by formula (I), ethylene oxide (EO) - modified trimethylolpropane tri(meth)acrylate (total EO addition mole number is 6 to 20) etc. can be cited.

[0418] The component (B) in this second embodiment may consist only of the compound (B1), or may be a mixture of the compound (B1) and other component (B).

[0419] When the component (B) of this second embodiment is a mixture, the content of the compound (B1) in the mixture is preferably 10% by mass or more, more preferably 10% by mass to 50% by mass, and further preferably 15% by mass to 35% by mass based on the total mass of the mixture.

[0420] In the photosensitive resin composition of this second embodiment, the content of the compound (B1) is preferably 5% by mass or more, more preferably 5.5% to 30% by mass, and still more preferably 6% to 20% by mass based on the total solid content of the photosensitive resin composition.

[0421] Here, the mechanism of achieving a photosensitive resin composition excellent in both development dispersibility and adhesion of fine patterns by including an alkali-soluble polymer having a specific acid equivalent and a specific amount of styrene units, the aforementioned component (B1), and acridine is not yet determined, but it is presumed that the interaction between the styrene units and the acridine component (based on π-electron stacking) and the interaction between the acid monomer and the aforementioned component (B1) (based on hydrogen bonding) are well manifested, and the overall compatibility is improved, which is beneficial to the above characteristics.

[0422] In this second embodiment, from the viewpoint of development dispersibility, the component (B) preferably contains a pentaerythritol-modified monomer (hereinafter referred to as "compound (B2)") together with the compound (B1). As the compound (B2), a tetra(meth)acrylate of a polyol obtained by adding preferably an average of 4 to 35 moles, more preferably 8 to 28 moles, and still more preferably 12 to 20 moles of an alkylene oxide to pentaerythritol is used.

[0423] The content of the compound (B2) in the component (B) is preferably 10% to 40% by mass, more preferably 15% to 30% by mass based on the total mass of the component (B).

[0424] The content of the compound (B2) in the photosensitive resin composition of this second embodiment is preferably 1% by mass or more, more preferably 1% to 20% by mass, and still more preferably 5% to 15% by mass.

[0425] The component (B) may also contain an olefinically unsaturated bond-containing compound other than the compounds (B1) and (B2).

[0426] The component (B) may also contain the following components:

[0427] Bisphenol A compounds, such as di(meth)acrylates of polyalkylene glycols obtained by adding an average of 2 to 15 moles of an alkylene oxide to both ends of bisphenol A, etc.;

[0428] Compounds having 3 olefinically unsaturated bonds (excluding B1), such as tri(meth)acrylates of polyalkylene triols obtained by adding an average of 3 to 25 moles of an alkylene oxide to trimethylolpropane, etc.

[0429] In the photosensitive resin composition of this second embodiment, the content of component (B) is preferably 1% by mass to 70% by mass, more preferably 5% by mass to 60% by mass, and still more preferably 10% by mass to 50% by mass. From the viewpoint of suppressing poor curing and delay in development time, its content is preferably 1% by mass or more. On the other hand, from the viewpoint of suppressing the generation of aggregates in the developer, it is preferably 70% by mass or less.

[0430] [Component (C): Photoinitiator]

[0431] Component (C) is a component that generates free radicals capable of initiating the polymerization of the aforementioned component (B) upon irradiation with light.

[0432] In this second embodiment, as the (B) photoinitiator, an acridine compound can be used. Furthermore, an acridine compound and other photoinitiators can be used in combination. Acridine-based compounds are preferably used to improve the sensitivity and resolution of the photosensitive resin composition of this second embodiment.

[0433] Examples of the acridine compound include 1,7-bis(9,9'-acridinyl)heptane, 9-phenylacridine, 9-methylacridine, 9-ethylacridine, 9-chloroethylacridine, 9-methoxyacridine, 9-ethoxyacridine, 9-(4-methylphenyl)acridine, 9-(4-ethylphenyl)acridine, 9-(4-n-propylphenyl)acridine, 9-(4-n-butylphenyl)acridine, 9-(4-tert-butylphenyl)acridine, 9-(4-methoxyphenyl)acridine, 9-(4-ethoxyphenyl)acridine, 9-(4-acetylphenyl)acridine, 9-(4-dimethylaminophenyl)acridine, 9-(4-chlorophenyl)acridine, 9-(4-bromophenyl)acridine, 9-(3-methylphenyl)acridine, 9-(3-tert-butylphenyl)acridine, 9-(3-acetylphenyl)acridine, 9-(3-dimethylaminophenyl)acridine, 9-(3-diethylaminophenyl)acridine, 9-(3-chlorophenyl)acridine, 9-(3-bromophenyl)acridine, 9-(2-pyridyl)acridine, 9-(3-pyridyl)acridine, 9-(4-pyridyl)acridine, etc.

[0434] Examples of other photoinitiators include:

[0435] 2-(o-chlorophenyl)-4,5-diphenylimidazolyl dimer, 2,2’,5-tris-(o-chlorophenyl)-4-(3,4-dimethoxyphenyl)-4’,5’-diphenylimidazolyl dimer, 2,4-bis-(o-chlorophenyl)-5-(3,4-dimethoxyphenyl)-diphenylimidazolyl dimer, 2,4,5-tris-(o-chlorophenyl)-diphenylimidazolyl dimer, 2-(o-chlorophenyl)-bis-4,5-(3,4-dimethoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2-fluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3-difluoromethylphenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,4-difluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,5-difluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,6-difluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,4-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,5-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,6-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,4,5-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,4,6-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,4,5-tetrafluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,4,6-tetrafluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,4,5,6-pentafluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer and other hexaarylbiimidazole compounds;

[0436] 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-bis-(methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer and other 2,4,5-triarylimidazole dimers (wherein, substances belonging to the above-mentioned hexaarylbiimidazole compounds are not included.);

[0437] Aromatic ketones such as benzophenone, N,N'-tetramethyl-4,4'-dimethylaminobenzophenone (Michler's ketone), N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropanone-1;

[0438] Quinone compounds such as 2-ethylanthraquinone, phenanthraquinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone;

[0439] Benzoin ether compounds such as benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether;

[0440] Benzil derivatives such as benzil methyl ketal;

[0441] N-phenylglycine derivatives, coumarin compounds, 4,4'-bis(diethylamino)benzophenone, etc.

[0442] The content of the acridine compound in the photosensitive resin composition of this second embodiment is preferably in the range of 0.001% by mass to 2% by mass, more preferably in the range of 0.01% by mass to 1.5% by mass, and still more preferably in the range of 0.1% by mass to 1% by mass.

[0443] The content of the component (C) in the photosensitive resin composition of this second embodiment (including the total content of the component (C) of the acridine compound) is preferably in the range of 0.1% by mass to 2% by mass, more preferably in the range of 0.2% by mass to 1.8% by mass, still more preferably in the range of 0.3% by mass to 1.7% by mass, and particularly preferably in the range of 0.4% by mass to 1.6% by mass.

[0444] From the viewpoint of improving sensitivity and resolution, the component (C) may further contain a sensitizer. Examples of such a sensitizer include N-aryl amino acids, organic halogen compounds, and other sensitizers.

[0445] Specifically, examples of the above N-aryl amino acids include N-phenylglycine, N-methyl-N-phenylglycine, N-ethyl-N-phenylglycine, etc.;

[0446] Examples of the organic halogen compounds include amyl bromide, isoamyl bromide, isobutene bromide, vinyl bromide, diphenylmethyl bromide, benzyl bromide, dibromomethane, tribromomethyl phenyl sulfone, carbon tetrabromide, tris(2,3-dibromopropyl) phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, a chlorotriazine compound, and the like.

[0447] Examples of the other sensitizers described above include:

[0448] Quinone compounds such as 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, 3-chloro-2-methylanthraquinone, and the like;

[0449] Aromatic ketone compounds such as benzophenone, Michler's ketone [4,4'-bis(dimethylamino)benzophenone], 4,4'-bis(diethylamino)benzophenone, and the like;

[0450] Benzoin ether compounds such as benzoin, benzoin ethyl ether, benzoin phenyl ether, methyl benzoin, ethyl benzoin, and the like;

[0451] Oxime ester compounds such as benzil dimethyl ketal, benzil diethyl ketal, 1-phenyl-1,2-propanedione-2-O-benzoyl oxime, 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime, and the like;

[0452] And the like.

[0453] From the viewpoints of the sensitivity of the composition and the peelability of the cured resist film, the content of the sensitizer in the photosensitive resin composition of this second embodiment is preferably 0.01% by mass to 5% by mass, more preferably 0.05% by mass to 3% by mass, and still more preferably 0.1% by mass to 2% by mass.

[0454] [Other Components]

[0455] The photosensitive resin composition of this second embodiment may further contain other components on the basis of the components (A) to (C) described above. Examples of the other components include coloring substances, halogen compounds, stabilizers, solvents, and the like.

[0456] Specifically, examples of the coloring substances include leuco dyes and other coloring substances;

[0457] Examples of the stabilizers include radical polymerization inhibitors, benzotriazole compounds, carboxybenzotriazole compounds, and the like.

[0458] <Leuco Dye>

[0459] As leuco dyes, for example, tris(4-dimethylaminophenyl)methane [leuco crystal violet], bis(4-dimethylaminophenyl)phenylmethane [leuco malachite green], etc. can be cited. In particular, from the viewpoint of good contrast, leuco crystal violet is preferably used.

[0460] The content of the leuco dye in the photosensitive resin composition is preferably 0.1% by mass to 10% by mass. When the content of the leuco dye is adjusted to 0.1% by mass or more, it is preferable from the viewpoint of obtaining the contrast between the exposed part and the unexposed part. On the other hand, when the content is adjusted to 10% by mass or less, it is preferable from the viewpoint of maintaining storage stability.

[0461] <Other coloring substances>

[0462] As other coloring substances, for example, magenta, phthalocyanine green, Auramine Base, paramagenta, crystal violet, methyl orange, Nile blue 2B, Victoria blue, malachite green (Aizen (registered trademark) MALACHITE GREEN manufactured by Hodogaya Chemical Co., Ltd.), basic blue 20, Diamond Green (Aizen (registered trademark) DIAMOND GREEN GH manufactured by Hodogaya Chemical Co., Ltd.), etc. can be cited.

[0463] The content of other coloring substances in the photosensitive resin composition is preferably 0.001% by mass to 1% by mass. When the content is adjusted to 0.001% by mass or more, it is preferable from the viewpoint of improving processability. On the other hand, when the content is adjusted to 1% by mass or less, it is preferable from the viewpoint of maintaining storage stability.

[0464] <Halogen compounds>

[0465] From the viewpoints of adhesion and contrast, it is a preferable mode to use a leuco dye and the following halogen compound in combination in the photosensitive resin composition.

[0466] As the halogen compound, for example, amyl bromide, isoamyl bromide, isobutylene bromide, vinyl bromide, diphenylmethyl bromide, benzyl bromide, dibromomethane, tribromomethyl phenyl sulfone, carbon tetrabromide, tris(2,3-dibromopropyl) phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, a chlorotriazine compound, etc. can be cited. Tribromomethyl phenyl sulfone is particularly preferred. When the content of the halogen compound in the photosensitive resin composition is 0.01% by mass to 3% by mass, it is preferable from the viewpoint of maintaining the storage stability of the hue of the photosensitive layer.

[0467] <Free radical polymerization inhibitor, benzotriazole compound, and carboxybenzotriazole compound>

[0468] Examples of the radical polymerization inhibitor include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, cuprous chloride, 2,6-di-tert-butyl-p-cresol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), aluminum salt of nitrosophenylhydroxylamine, diphenylnitrosamine, and the like.

[0469] Examples of the benzotriazole compound include 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-tolyltriazole, bis(N-2-hydroxyethyl)aminomethylene-1,2,3-benzotriazole, and the like.

[0470] Examples of the carboxybenzotriazole compound include 4-carboxy-1,2,3-benzotriazole, 5-carboxy-1,2,3-benzotriazole, N-(N,N-di-2-ethylhexyl)aminomethylenecarboxybenzotriazole, N-(N,N-di-2-hydroxyethyl)aminomethylenecarboxybenzotriazole, N-(N,N-di-2-ethylhexyl)aminoethylenecarboxybenzotriazole, and the like.

[0471] The total content of the radical polymerization inhibitor, benzotriazole compound, and carboxybenzotriazole compound in the photosensitive resin composition is preferably 0.01% by mass to 3% by mass, more preferably 0.05% by mass to 1% by mass. When the content is adjusted to 0.01% by mass or more, it is preferable from the viewpoint of imparting storage stability to the photosensitive resin composition. On the other hand, when the content is adjusted to 3% by mass or less, it is preferable from the viewpoints of maintaining sensitivity and suppressing decolorization of the dye.

[0472] <Plasticizer>

[0473] The photosensitive resin composition may also contain a plasticizer as needed. Examples of the plasticizer include phthalic acid esters such as diethyl phthalate, o-toluenesulfonamide, p-toluenesulfonamide, tributyl citrate, triethyl citrate, acetyltriethyl citrate, acetyltripropyl citrate, acetyltributyl citrate, polyethylene glycol, polypropylene glycol, polyethylene glycol alkyl ether, polypropylene glycol alkyl ether, and the like.

[0474] The content of the plasticizer in the photosensitive resin composition is preferably 1% by mass to 50% by mass, more preferably 1% by mass to 30% by mass. When the content is adjusted to 1% by mass or more, it is preferable from the viewpoints of suppressing the delay of the development time and imparting flexibility to the cured film. On the other hand, when the content is adjusted to 50% by mass or less, it is preferable from the viewpoints of suppressing insufficient curing and edge fusion.

[0475] <Solvent>

[0476] The photosensitive resin composition may also contain a solvent. Examples of the solvent include ketones typified by methyl ethyl ketone (MEK); alcohols typified by methanol, ethanol, and isopropyl alcohol, etc. The solvent is preferably added to the photosensitive resin composition such that the viscosity of the solution of the photosensitive resin composition coated on the support film is 500 mPa·s to 4000 mPa·s at 25°C.

[0477] <Photosensitive Element>

[0478] In this second embodiment, the photosensitive element is a laminate (photosensitive resin laminate) obtained by laminating a photosensitive resin layer formed from the above photosensitive resin composition on a support. The photosensitive element may also have a protective layer on the surface of the photosensitive resin layer opposite to the support as needed.

[0479] [Support]

[0480] As the support, a transparent substrate that transmits light emitted from the self-exposure light source is preferred. Examples of the support include polyethylene terephthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, polymethyl methacrylate copolymer film, polystyrene film, polyacrylonitrile film, styrene copolymer film, polyamide film, cellulose derivative film, etc. As these films, stretched films may also be used as needed.

[0481] The haze of the support is preferably 5 or less.

[0482] When the thickness of the support is thin, it is advantageous in terms of image formability and economy, but the strength needs to be maintained. Considering both of these, a support of 10 μm to 30 μm can be preferably used.

[0483] [Photosensitive Resin Layer]

[0484] When the photosensitive resin composition used in the formation of the photosensitive resin layer contains a solvent, the solvent is preferably removed from the photosensitive resin layer, but may also remain in the photosensitive resin layer.

[0485] The thickness of the photosensitive resin layer is preferably 5 μm to 100 μm, more preferably 7 μm to 60 μm. The thinner the thickness, the higher the resolution, and the thicker the thickness, the higher the film strength. Therefore, the thickness of the photosensitive resin layer can be appropriately selected within the range of 5 μm to 100 μm according to the use.

[0486] [Protective layer]

[0487] An important characteristic of the protective layer is that the adhesion force to the photosensitive resin layer is sufficiently smaller than the adhesion force between the support and the photosensitive resin layer, and it can be easily peeled off. As the protective layer, for example, a polyethylene film, a polypropylene film, etc. can be preferably used, and also a film having excellent peelability disclosed in, for example, Japanese Patent Laid-Open No. 59-202457 can be used.

[0488] The thickness of the protective layer is preferably 10 μm to 100 μm, more preferably 10 μm to 50 μm.

[0489] [Method for manufacturing a photosensitive element]

[0490] A photosensitive element can be manufactured by sequentially laminating a support, a photosensitive resin layer, and a protective layer as needed. As a lamination method of the support, the photosensitive resin layer, and the protective layer, a known method can be adopted.

[0491] For example, a solvent is added to the photosensitive resin composition and mixed to prepare a formulation liquid, and then it is coated on the support using a bar coater or a roll coater and dried to form a photosensitive resin layer formed of the photosensitive resin composition on the support. Then, a protective layer is laminated on the formed photosensitive resin layer as needed, whereby a photosensitive element can be manufactured.

[0492] <Method for forming an anti-etching pattern>

[0493] The above-mentioned photosensitive element can be used to form an anti-etching pattern on a substrate.

[0494] The method for forming an anti-etching pattern preferably sequentially includes the following steps:

[0495] A lamination step of laminating the photosensitive resin layer of the photosensitive element on a conductor substrate,

[0496] An exposure step of exposing the laminated photosensitive resin layer, and

[0497] A development step of removing the unexposed portion after the above exposure with a developer.

[0498] The lamination step is preferably a step of laminating the photosensitive resin layer of the photosensitive element on the conductive substrate with a wetting agent sandwiched therebetween. The wetting agent preferably includes at least one selected from pure water, deionized water and electrolyzed water, and a copper chelating agent (e.g., at least one selected from the group consisting of imidazole compounds, triazole compounds, pyridine compounds and pyrazole compounds).

[0499] In the method for forming a resist pattern of the second embodiment, first, in a lamination step, a photosensitive resin layer is formed on a substrate using a laminator. Specifically, when the photosensitive element has a protective layer, the protective layer is peeled off and then the photosensitive resin layer is laminated by heat-pressing the substrate surface using a laminator.

[0500] As the substrate, a metal plate or an insulating substrate having a metal film is used. As the material of the metal, for example, copper, stainless steel (SUS), glass, indium tin oxide (ITO) etc. can be listed. These substrates may also have through holes for coping with multilayer substrates.

[0501] The photosensitive resin layer may be laminated only on one side of the substrate surface, or may be laminated on both sides of the substrate as required. The heating temperature during lamination is preferably 40°C to 160°C. From the viewpoint of further improving the adhesion of the obtained resist pattern to the substrate, it is preferred to perform heat pressing twice or more. When performing pressing twice or more, a two-stage laminator with two rollers may be used, or the laminate of the substrate and the photosensitive resin layer may be repeatedly pressed by rollers several times.

[0502] Next, in the exposure step, the photosensitive resin layer is exposed using an exposure machine. The exposure may be performed through the support without peeling the support, or may be performed after peeling the support as necessary.

[0503] By performing this exposure in a pattern, after the development process described later, a resist film (resist pattern) having a desired pattern can be obtained. The patterned exposure can be performed by any method of exposure through a photomask and maskless exposure. When the exposure is performed through a photomask, the exposure amount is determined by the light source illumination and the exposure time. The exposure amount can be measured using a light meter.

[0504] In maskless exposure, exposure is performed on the substrate using a direct drawing device without using a photomask. As the light source, a semiconductor laser with a wavelength of 350nm to 410nm, an ultra-high pressure mercury lamp, etc. are used. In maskless exposure, the drawing pattern is controlled by a computer, and the exposure amount is determined by the illumination of the exposure light source and the moving speed of the substrate.

[0505] Next, in the development step, the unexposed portion of the photosensitive resin layer is removed with a developer. After exposure, when there is a support on the photosensitive resin layer, it is preferably removed before subjecting the layer to the development step.

[0506] In the developing process, a developer formed from an alkaline aqueous solution is used to develop and remove the unexposed portions to obtain a resist image. As the alkaline aqueous solution, for example, an aqueous solution of Na 2 CO 3 , K 2 CO 3 etc. is preferably used. The alkaline aqueous solution is selected according to the characteristics of the photosensitive resin layer, and an aqueous solution of Na 2 CO 3 with a concentration of 0.2% by mass to 2% by mass is preferably used. A surfactant, an antifoaming agent, a small amount of an organic solvent for promoting development, etc. may also be mixed into the alkaline aqueous solution.

[0507] The temperature of the developer in the developing process is preferably maintained at a constant temperature within the range of 20°C to 40°C.

[0508] A resist pattern is obtained through the above process. Depending on the situation, a heating process at 100°C to 300°C may be further performed. The implementation of this heating process is suitable from the viewpoint of further improving chemical resistance. Heating can be carried out using a heating furnace in a suitable manner such as hot air, infrared rays, far-infrared rays, etc.

[0509] <Method for forming a circuit board>

[0510] The method for forming a circuit board according to this second embodiment preferably sequentially includes the following processes:

[0511] A lamination process of laminating the photosensitive resin layer of the photosensitive element on the conductor substrate,

[0512] An exposure process of exposing the laminated photosensitive resin layer,

[0513] A developing process of removing the unexposed portions after the above exposure with a developer,

[0514] A conductor pattern forming process of etching or plating the conductor substrate on which a resist pattern is formed through the above development, and

[0515] A stripping process of stripping the above resist pattern.

[0516] The lamination process is preferably a process of laminating the photosensitive resin layer of the photosensitive element on the conductor substrate with a wetting agent interposed therebetween. As the wetting agent, it preferably contains one or more selected from pure water, deionized water, and electrolyzed water, and a copper chelating agent (for example, one or more compounds selected from the group consisting of imidazole compounds, triazole compounds, pyridine compounds, and pyrazole compounds).

[0517] In the conductor pattern forming process, a conductor pattern can be formed on the substrate surface (such as a copper surface) exposed through the developing process on the substrate on which a resist pattern is formed using a known etching method or plating method.

[0518] In the stripping step, the substrate having the conductor pattern formed thereon is brought into contact with an appropriate stripping liquid to strip and remove the resist pattern. Through this step, a desired circuit board is obtained.

[0519] The stripping liquid used in the stripping step is preferably an alkaline aqueous solution. As such an alkaline aqueous solution, for example, a 2 mass% to 5 mass% NaOH aqueous solution or KOH aqueous solution is preferably used. A small amount of a water-soluble solvent such as alcohol or the like may also be added to the stripping liquid. The temperature of the stripping liquid in the stripping step is preferably 40°C to 70°C.

[0520] The photosensitive resin composition, photosensitive element, and method for forming a circuit board in this second embodiment can be extremely suitable for use in the manufacture of, for example, printed circuit boards, lead frames, substrates having concavo-convex patterns, semiconductor packages, and the like.

[0521] It should be noted that regarding the measurement methods of the above various parameters, in the case where there is no special description, they are measured according to the measurement methods in the examples described later.

[0522] <Third Embodiment>

[0523] Hereinafter, a mode for implementing the third embodiment of the present invention (hereinafter also simply referred to as "this third embodiment") will be specifically described.

[0524] <Photosensitive Resin Composition>

[0525] In this third embodiment, the photosensitive resin composition contains (A) an alkali-soluble polymer, (B) a compound having an ethylenically unsaturated bond, and (C) a photopolymerization initiator. According to requirements, the photosensitive resin composition may further contain other components such as (D) additives.

[0526] It should be noted that in this specification, "(meth)acrylic acid" means acrylic acid or methacrylic acid, "(meth)acryloyl" means acryloyl or methacryloyl, and "(meth)acrylate" means "acrylate" or "methacrylate".

[0527] (A) Alkali-soluble polymer

[0528] (A) The alkali-soluble polymer is a polymer soluble in an alkaline substance. In this third embodiment, from the viewpoint of balancing the hole covering property of the resist pattern and the suppression of water residue short-circuit failures, preferably, the (A) alkali-soluble polymer contains 10 mass% to 24 mass% of structural units of (meth)acrylic acid and 35 mass% to 90 mass% of structural units of styrene based on the total mass of the monomers constituting the (A) alkali-soluble polymer.

[0529] Based on the total mass of the monomers constituting the (A) alkali-soluble polymer, the content of the structural unit of (meth)acrylic acid in the (A) alkali-soluble polymer is preferably 24% by mass or less from the viewpoint of suppressing water residue short-circuit failures, and preferably 10% by mass or more from the viewpoints of ensuring alkali developability and alkali peelability. The upper limit value of the content is more preferably 23% by mass or 22.5% by mass, and the lower limit value is more preferably 11% by mass, 15% by mass, 18% by mass, or 20% by mass. Water residue short-circuit failures are strongly related to the hydrophobicity of the cured resist. By increasing the hydrophobicity of the resist, i.e., the water contact angle, water residue short-circuit failures can be suppressed.

[0530] Regarding the content of the structural unit of (meth)acrylic acid in the (A) alkali-soluble polymer, the acid equivalent of the (A) alkali-soluble polymer (when the (A) component contains multiple copolymers, the acid equivalent for the entire mixture) is preferably 100 or more from the viewpoints of the developability resistance of the photosensitive resin layer, and the development tolerance, resolution, and adhesion of the resist pattern, and preferably 900 or less from the viewpoints of the developability and peelability of the photosensitive resin layer. The acid equivalent of the (A) alkali-soluble polymer is more preferably 250 to 600, and further preferably 350 to 500. The acid equivalent refers to the mass of a linear polymer having 1 equivalent of carboxyl groups therein.

[0531] Based on the total mass of the monomers constituting the (A) alkali-soluble polymer, the content of the structural unit of styrene in the (A) alkali-soluble polymer is preferably 90% by mass or less from the viewpoint of developability, and preferably 35% by mass or more from the viewpoints of resolution and suppression of water residue short-circuit failures. The upper limit value of the content is more preferably 85% by mass, 80% by mass, 70% by mass, or 60% by mass from the viewpoints of developability and prevention of delay in peeling time, and the lower limit value is more preferably 36% by mass, 38% by mass, 40% by mass, or 42% by mass from the viewpoints of resolution and suppression of water residue short-circuit failures.

[0532] From the viewpoint of improving the hole covering property of the resist pattern, it is preferable that the (A) alkali-soluble polymer further contains a structural unit of butyl (meth)acrylate. The structural unit of butyl (meth)acrylate may also contain repeating units derived from at least one selected from the group consisting of n-butyl (meth)acrylate, isobutyl (meth)acrylate, and tert-butyl (meth)acrylate.

[0533] From the viewpoint of balancing the hole covering property and the suppression of water residue short-circuit failures, the content of the structural unit of butyl (meth)acrylate in the (A) alkali-soluble polymer is preferably in the range of 0.1% by mass to 5% by mass, and more preferably 0.3% by mass to 1% by mass, based on the total mass of the monomers constituting the (A) alkali-soluble polymer.

[0534] (A) The alkali-soluble polymer can be a single copolymer or a mixture of a plurality of copolymers and / or a mixture of a plurality of homopolymers as long as it contains 10% by mass to 24% by mass of a structural unit of (meth)acrylic acid and 35% by mass to 90% by mass of a structural unit of styrene based on the total mass of the monomers constituting the (A) alkali-soluble polymer.

[0535] (A) The alkali-soluble polymer can include poly(meth)acrylic acid, poly(n-butyl methacrylate), polystyrene, a copolymer obtained by copolymerizing a copolymerization component containing one or more of (meth)acrylic acid and / or styrene and one or more of the following first monomers and / or one or more of the following second monomers, and the like.

[0536] The first monomer is a monomer having a carboxyl group in the molecule (excluding (meth)acrylic acid). Examples of the first monomer include fumaric acid, cinnamic acid, crotonic acid, itaconic acid, maleic anhydride, and maleic acid semiester.

[0537] The second monomer is a non-acidic monomer having at least one polymerizable unsaturated group in the molecule (excluding styrene). Examples of the second monomer include esters of vinyl alcohol such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, benzyl (meth)acrylate, and vinyl acetate; (meth)acrylonitrile; polymerizable styrene derivatives, and the like.

[0538] Among them, from the viewpoint of improving the hole covering property of the resist pattern, n-butyl (meth)acrylate, isobutyl (meth)acrylate, or tert-butyl (meth)acrylate is preferred, and n-butyl (meth)acrylate is more preferred from the viewpoint of hole covering property. In addition, a polymerizable styrene derivative is preferred from the viewpoints of improving resolution and suppressing water residue short circuit failure.

[0539] Examples of the polymerizable styrene derivative include methylstyrene, vinyltoluene, tert-butoxystyrene, acetoxystyrene, 4-vinylbenzoic acid, styrene dimer, styrene trimer, and the like.

[0540] The alkali-soluble polymer is preferably synthesized as follows: An appropriate amount of a radical polymerization initiator such as benzoyl peroxide or azobisisobutyronitrile is added to a solution prepared by mixing the above monomers and diluting with a solvent such as acetone, methyl ethyl ketone, methanol, ethanol, n-propanol, or isopropanol, followed by heating and stirring to effect synthesis. Sometimes, synthesis is carried out while dropping a part of the mixture into the reaction solution. Sometimes, a solvent is further added after completion of the reaction to adjust to a desired concentration. As a synthesis method, in addition to solution polymerization, bulk polymerization, suspension polymerization, or emulsion polymerization can also be used.

[0541] (A) The weight-average molecular weight of the alkali-soluble polymer (when the (A) component contains a plurality of copolymers, the weight-average molecular weight for the entire mixture) is preferably from 5000 to 500000. The weight-average molecular weight of the (A) alkali-soluble polymer is preferably 5000 or more from the viewpoint of maintaining the thickness uniformity of the dry film resist and obtaining resistance to the developer, and preferably 500000 or less from the viewpoint of maintaining the developability of the dry film resist. The weight-average molecular weight of the (A) alkali-soluble polymer is more preferably from 10000 to 200000, and still more preferably from 20000 to 100000. The dispersity of the (A) alkali-soluble polymer is preferably from 1.0 to 6.0.

[0542] In this third embodiment, the content of the (A) alkali-soluble polymer in the photosensitive resin composition is preferably in the range of 10% by mass to 90% by mass, more preferably 20% by mass to 80% by mass, and still more preferably 40% by mass to 60% by mass, based on the total amount of the solid components of the photosensitive resin composition (hereinafter, the same applies to each component contained, unless otherwise specified). The content of the (A) alkali-soluble polymer is preferably 10% by mass or more from the viewpoint of maintaining the alkali developability of the photosensitive resin layer, and preferably 90% by mass or less from the viewpoint of allowing the resist pattern formed by exposure to fully exhibit the performance as a resist material.

[0543] (B) An ethylenically unsaturated bond-containing compound

[0544] (B) The ethylenically unsaturated bond-containing compound is a compound having polymerizability by having an ethylenically unsaturated group in its structure. The ethylenically unsaturated bond is preferably a terminal ethylenically unsaturated group from the viewpoint of addition polymerizability.

[0545] In the third embodiment, when (A) an alkali-soluble polymer and (B) a compound having an ethylenically unsaturated bond are used in combination, from the viewpoint of ensuring the hole covering property of the resist pattern, the weight average molecular weight of (B) the compound having an ethylenically unsaturated bond is preferably 1200 or more. In this specification, regarding the weight average molecular weight of (B) the compound having an ethylenically unsaturated bond, when (B) the compound having an ethylenically unsaturated bond is a single kind, it means the weight average molecular weight derived from the structural formula of the single kind of compound having an ethylenically unsaturated bond, and when (B) the compound having an ethylenically unsaturated bond is composed of a plurality of kinds, it means the weighted average of the weight average molecular weights of the respective compounds having an ethylenically unsaturated bond and the compounding ratios.

[0546] From the viewpoint of further improving the hole covering property of the resist pattern, the weight average molecular weight of (B) the compound having an ethylenically unsaturated bond is more preferably 1300 or more, further preferably 1400 or more, and from the viewpoints of the resolution and peelability of the resist pattern, it is more preferably 5000 or less, further preferably 4000 or less, and particularly preferably 3000 or less.

[0547] (B) The compound having an ethylenically unsaturated bond may contain at least one selected from the group consisting of the following (b 1 ) to (b 5 ):

[0548] (b 1 ) An ethylene glycol di(meth)acrylate compound represented by the following general formula (I):

[0549]

[0550] {In the formula, R 1 and R 2 each independently represent a hydrogen atom or a methyl group, and m 1 is a number satisfying 2 to 40.};

[0551] (b 2 ) An alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the following general formula (II):

[0552]

[0553] {In the formula, R 3 and R 4 each independently represent a hydrogen atom or a methyl group, A is C 2 H 4 , B is C 3 H 6 , n 1 , n 2 , n 3 and n 4 are numbers satisfying n 1 + n2 +n 3 +n 4 is an integer in the range of 2 to 50. The arrangement of the repeating units of -(A-O)- and -(B-O)- can be random or block. In the case of block arrangement, either -(A-O)- or -(B-O)- is optionally on the biphenyl side.}

[0554] (b 3 ) A tri(meth)acrylate compound represented by the following general formula (III):

[0555]

[0556] {In the formula, R 5 to R 7 each independently represent a hydrogen atom or a methyl group, X represents an alkylene group having 2 to 6 carbon atoms, m 2 , m 3 and m 4 are each independently an integer from 0 to 40, and m 2 + m 3 + m 4 is from 1 to 40, and when m 2 + m 3 + m 4 is 2 or more, the plurality of X's are optionally the same or different from each other};

[0557] (b 4 ) A carbamate di(meth)acrylate compound represented by the following general formula (IV):

[0558]

[0559] {In the formula, R 8 and R 9 each independently represent a hydrogen atom or a methyl group, Y represents an alkylene group having 2 to 6 carbon atoms, Z represents a divalent organic group, and s and t are each independently an integer from 0 to 40, and s + t ≥ 1}; and

[0560] (b 5 ) An addition polymerizable monomer other than the above (b 1 ) to (b 4 ).

[0561] From the viewpoint of adjusting the peeling time of the resist pattern and the size of the peeling sheet, the ethylenically unsaturated bond-containing compound (B) preferably contains the ethylene glycol di(meth)acrylate compound represented by (b 1 ).

[0562] In the general formula (I), m 1It is preferably 2 or more from the viewpoints of stripping time and stripping sheet size, and preferably 40 or less from the viewpoints of resolution, plating resistance, and etching resistance. m 1 It is more preferably 4 to 20, and further preferably 6 to 12.

[0563] As a specific example of the ethylene glycol di(meth)acrylate compound represented by the general formula (I), preferably m 1 tetraethylene glycol di(meth)acrylate with m = 4, m 1 nonaethylene glycol di(meth)acrylate with m = 9, or m 1 polyethylene glycol di(meth)acrylate with m = 14.

[0564] From the viewpoints of resolution and hole covering property, the ethylenically unsaturated bond-containing compound (B) preferably contains (b 2 ) an alkylene oxide-modified bisphenol A type di(meth)acrylate compound represented by the general formula (II). B in the general formula (II) can be -CH 2 CH 2 CH 2 - or -CH(CH 3 )CH 2 -.

[0565] The hydrogen atoms on the aromatic ring in the general formula (II) may be substituted with heteroatoms and / or substituents.

[0566] Examples of the heteroatom include a halogen atom, etc., and examples of the substituent include an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aryl group having 6 to 18 carbon atoms, benzoylmethyl, an amino group, an alkylamino group having 1 to 10 carbon atoms, a dialkylamino group having 2 to 20 carbon atoms, a nitro group, a cyano group, a carbonyl group, a mercapto group, an alkylthio group having 1 to 10 carbon atoms, an aryl group, a hydroxyl group, a hydroxyalkyl group having 1 to 20 carbon atoms, a carboxyl group, a carboxyalkyl group having 1 to 10 carbon atoms in the alkyl group, an acyl group having 1 to 10 carbon atoms in the alkyl group, an alkoxy group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 1 to 20 carbon atoms, an alkylcarbonyl group having 2 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an N-alkylcarbamoyl group having 2 to 10 carbon atoms or a heterocyclic group-containing group, or an aryl group substituted with these substituents, etc. These substituents may form a fused ring, or the hydrogen atoms in these substituents may be substituted with heteroatoms such as a halogen atom. When the aromatic ring in the general formula (II) has a plurality of substituents, the plurality of substituents may be the same or different.

[0567] R 3 and R 4 in the general formula (II) are each independently a hydrogen atom or a methyl group, and from the viewpoint of ensuring contrast immediately after exposure of the photosensitive resin layer formed from the photosensitive resin composition, preferably R 3 and R 4One or both of them are hydrogen atoms, and more preferably R 3 and R 4 Both are hydrogen atoms.

[0568] From the viewpoint of hole covering property, it is preferable that (b 2 ) A longer-chain alkylene oxide is added to the alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the general formula (II). More specifically, in the general formula (II), n 1 , n 2 , n 3 and n 4 Preferably satisfy the relationship of n 1 +n 2 +n 3 +n 4 = 4 to 50, more preferably satisfy the relationship of n 1 +n 2 +n 3 +n 4 = 10 to 50, further preferably satisfy the relationship of n 1 +n 2 +n 3 +n 4 = 20 to 50, particularly preferably satisfy the relationship of n 1 +n 2 +n 3 +n 4 = 30 to 50.

[0569] From the viewpoint of hole covering property, 40% by mass or more of the ethylenically unsaturated bond-containing compound (B) is preferably (b 2 ) the alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the general formula (II), and more preferably n 1 , n 2 , n 3 and n 4 in the general formula (II) satisfy the relationship of n 1 +n 2 +n 3 +n 4 = 30 to 50 of the alkylene oxide-modified bisphenol A di(meth)acrylate compound. More preferably, 50% by mass, further preferably 55% by mass or more, and most preferably 60% by mass of the ethylenically unsaturated bond-containing compound (B) is (b 2 ) the alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the general formula (II).

[0570] As (b 2Preferred specific examples of the alkylene oxide-modified bisphenol A type di(meth)acrylate compound represented by the general formula (II) include di(meth)acrylates of polyethylene glycol obtained by adding an average of 1 unit of ethylene oxide to both ends of bisphenol A, di(meth)acrylates of polyethylene glycol obtained by adding an average of 2 units of ethylene oxide to both ends of bisphenol A, di(meth)acrylates of polyethylene glycol obtained by adding an average of 5 units of ethylene oxide to both ends of bisphenol A, di(meth)acrylates of polyethylene glycol obtained by adding an average of 7 units of ethylene oxide to both ends of bisphenol A, di(meth)acrylates of polyalkylene glycol obtained by adding an average of 6 units of ethylene oxide and an average of 2 units of propylene oxide to both ends of bisphenol A, di(meth)acrylates of polyalkylene glycol obtained by adding an average of 15 units of ethylene oxide to both ends of bisphenol A, di(meth)acrylates of polyalkylene glycol obtained by adding an average of 15 units of ethylene oxide and an average of 2 units of propylene oxide to both ends of bisphenol A, and the like.

[0571] In the general formula (II), from the viewpoints of resolution and suppression of water residue short-circuit failure, n 1 , n 2 , n 3 and n 4 also preferably satisfy the relationship of n 1 +n 2 +n 3 +n 4 = 2 to 10, and particularly preferably satisfy the relationship of n 1 +n 2 +n 3 +n 4 = 2 to 4.

[0572] From the viewpoint of achieving a balance between hole covering property and suppression of water residue short-circuit failure, particularly preferably, the ethylenically unsaturated bond-containing compound (B) simultaneously contains a compound satisfying n 1 +n 2 +n 3 +n 4 = 30 to 50 in the general formula (II), a compound in which one or both of R 3 and R 4 in the general formula (II) are hydrogen atoms, and a compound satisfying n 1 +n 2 +n 3 +n 4 = 2 to 10 in the general formula (II).

[0573] From the viewpoints of resolution and hole covering property, the ethylenically unsaturated bond-containing compound (B) preferably contains (b 3The tri(meth)acrylate compound represented by the general formula (III). In the general formula (III), X may be an alkylene group having 2 to 6 carbon atoms, such as -CH 2 CH 2 -, -CH 2 CH 2 CH 2 -, -CH(CH 3 )CH 2 - etc.

[0574] From the viewpoint of hole covering property, (b 3 ) the tri(meth)acrylate compound represented by the general formula (III) preferably has a longer-chain alkylene oxide moiety. More specifically, in the general formula (III), m 2 +m 3 +m 4 is preferably 10 to 40, more preferably 20 to 40.

[0575] As a preferable specific example of (b 3 ) the tri(meth)acrylate compound represented by the general formula (III), there can be mentioned ethylene oxide (EO) modified trimethylolpropane tri(meth)acrylate (average addition molar number of EO: 10 to 40), propylene oxide (PO) modified trimethylolpropane tri(meth)acrylate (average addition molar number of PO: 10 to 40), etc.

[0576] From the viewpoint of hole covering property, (B) the ethylenically unsaturated bond-containing compound preferably contains (b 4 ) the urethane di(meth)acrylate compound represented by the general formula (IV).

[0577] In the general formula (IV), Z represents a divalent organic group, for example, it can be an alkylene group having 1 to 10 carbon atoms, an alkylene oxide group having 2 to 10 carbon atoms, a divalent alicyclic group having 3 to 10 carbon atoms which may have a substituent, etc.

[0578] In the general formula (IV), Y represents an alkylene group having 2 to 6 carbon atoms, for example, it can be -CH 2 CH 2 -, -CH 2 CH 2 CH 2 -, -CH(CH 3 )CH 2 - etc.

[0579] From the viewpoint of further improving the hole covering property, it is also preferable that the -(Y-O) s - moiety and the -(Y-O) t - moiety in the general formula (IV) are each independently replaced by -(C 2 H 5O)-(C 3 H 6 O) 9 - substitution.

[0580] As (b 4 ) Preferred specific examples of the urethane di(meth)acrylate compounds represented by the general formula (IV) include addition reaction products of (meth)acrylic monomers having a hydroxyl group at the β-position and diisocyanate compounds such as isophorone diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, and 1,6-hexamethylene diisocyanate, tris((meth)acryloyloxy tetraethylene glycol isocyanate) hexamethylene isocyanurate, EO-modified urethane di(meth)acrylate, and EO, PO-modified urethane di(meth)acrylate. It should be noted that EO represents ethylene oxide, and the EO-modified compound has a block structure of ethylene oxide groups. In addition, PO represents propylene oxide, and the PO-modified compound has a block structure of propylene oxide groups. As the EO-modified urethane di(meth)acrylate, for example, the product named "UA-11" manufactured by Shin-Nakamura Chemical Co., Ltd. can be cited. In addition, as the EO, PO-modified urethane di(meth)acrylate, for example, the product named "UA-13" manufactured by Shin-Nakamura Chemical Co., Ltd. can be cited. They can be used alone or in combination of two or more.

[0581] (B) The ethylenically unsaturated bond-containing compound may contain an addition polymerizable monomer other than (b 1 ) to (b 4 ) components as (b 5 ) component.

[0582] As (b 5 ) component, the following substances can be cited:

[0583] Tris(meth)acrylate other than (b 3 ) component, such as trimethylolpropane tris(meth)acrylate, ethoxylated glycerol tris(meth)acrylate, ethoxylated isocyanuric acid tris(meth)acrylate, pentaerythritol tris(meth)acrylate, etc.;

[0584] Tetrakis(meth)acrylate, such as ditrimethylolpropane tetrakis(meth)acrylate, pentaerythritol tetrakis(meth)acrylate, dipentaerythritol tetrakis(meth)acrylate, pentaerythritol (poly)alkoxy tetrakis(meth)acrylate, etc.;

[0585] Penta(meth)acrylate, such as dipentaerythritol penta(meth)acrylate, etc.;

[0586] Hexa(meth)acrylates such as dipentaerythritol hexa(meth)acrylate, hexa(meth)acrylates obtained by adding a total of 1 to 24 moles of ethylene oxide to the 6 terminals of dipentaerythritol, hexa(meth)acrylates obtained by adding a total of 1 to 10 moles of ε-caprolactone to the 6 terminals of dipentaerythritol, etc.;

[0587] Acrylate compounds having 1 (meth)acryloyl group;

[0588] Compounds obtained by reacting a polyol with an α,β-unsaturated carboxylic acid;

[0589] Compounds obtained by reacting a glycidyl group-containing compound with an α,β-unsaturated carboxylic acid; and

[0590] Phthalic acid-based compounds such as γ-chloro-2-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate and β-hydroxyalkyl-β'-(meth)acryloyloxyalkyl-phthalate, etc.

[0591] In this third embodiment, from the viewpoints of the hole covering property and adhesion of the resist pattern, the total content of all (B) ethylenically unsaturated bond-containing compounds in the photosensitive resin composition is preferably in the range of 1 mass% to 70 mass%, more preferably 2 mass% to 60 mass%, and further preferably 4 mass% to 50 mass%.

[0592] (C) Photoinitiator

[0593] (C) The photoinitiator is a compound that polymerizes a monomer using light. The photosensitive resin composition contains compounds known in the art as photoinitiators.

[0594] The content of (C) photoinitiator in the photosensitive resin composition is preferably in the range of 0.01 to 20 mass%, more preferably 0.05 mass% to 10 mass%, and further preferably 0.1 mass% to 7 mass%. The content of (C) photoinitiator is preferably 0.01 mass% or more from the viewpoint of obtaining sufficient sensitivity, and preferably 20 mass% or less from the viewpoint of allowing light to sufficiently penetrate to the bottom surface of the resist and obtaining good high resolution.

[0595] Examples of (C) photoinitiators include quinones, aromatic ketones, acetophenones, acylphosphine oxides, benzoin or benzoin ethers, dialkyl ketals, thioxanthones, dialkylaminobenzoates, oxime esters, acridines, etc. Further, hexaarylbiimidazoles, pyrazoline compounds, N-aryl amino acids or their ester compounds (e.g., N-phenylglycine), organic halogen compounds, etc. can be cited. They can be used alone or in combination of two or more. Among them, acridines are particularly suitable for direct imaging exposure.

[0596] As acridines, for example, acridine, 9-phenylacridine, 1,6-bis(9-acridinyl)hexane, 1,7-bis(9-acridinyl)heptane, 1,8-bis(9-acridinyl)octane, 1,9-bis(9-acridinyl)nonane, 1,10-bis(9-acridinyl)decane, 1,11-bis(9-acridinyl)undecane, 1,12-bis(9-acridinyl)dodecane and other acridine derivatives can be cited. From the viewpoint of adaptability to direct imaging exposure, the content of acridines in the photosensitive resin composition is preferably in the range of 0.1% by mass to 5% by mass, more preferably in the range of 0.3% by mass to 3% by mass, and still more preferably in the range of 0.5% by mass to 2% by mass.

[0597] As aromatic ketones, for example, benzophenone, Michler's ketone [4,4'-bis(dimethylamino)benzophenone], 4,4'-bis(diethylamino)benzophenone, 4-methoxy-4'-dimethylaminobenzophenone can be cited. They can be used alone or in combination of two or more. Among them, from the viewpoint of adhesion, 4,4'-bis(diethylamino)benzophenone is preferred. Further, from the viewpoint of transmittance, the content of aromatic ketones in the photosensitive resin composition is preferably in the range of 0.01% by mass to 0.5% by mass, and more preferably in the range of 0.02% by mass to 0.3% by mass.

[0598] Examples of hexaarylbiimidazole include 2-(o-chlorophenyl)-4,5-diphenylbiimidazole, 2,2’,5-tris-(o-chlorophenyl)-4-(3,4-dimethoxyphenyl)-4’,5’-diphenylbiimidazole, 2,4-bis-(o-chlorophenyl)-5-(3,4-dimethoxyphenyl)-diphenylbiimidazole, 2,4,5-tris-(o-chlorophenyl)-diphenylbiimidazole, 2-(o-chlorophenyl)-bis-4,5-(3,4-dimethoxyphenyl)-biimidazole, 2,2’-bis-(2-fluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,3-difluoromethylphenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,4-difluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,5-difluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,6-difluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,3,4-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,3,5-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,3,6-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,4,5-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,4,6-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,3,4,5-tetrafluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2’-bis-(2,3,4,6-tetrafluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, and 2,2’-bis-(2,3,4,5,6-pentafluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-biimidazole, etc. They can be used alone or in combination of two or more. From the viewpoints of high sensitivity, resolution, and adhesion, 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer is preferred.

[0599] In this third embodiment, from the viewpoint of improving the peeling characteristics and / or sensitivity of the photosensitive resin layer, the content of the hexaarylbiimidazole compound in the photosensitive resin composition is preferably in the range of 0.05% by mass to 7% by mass, more preferably in the range of 0.1% by mass to 6% by mass, and further preferably in the range of 1% by mass to 4% by mass.

[0600] As N-aryl amino acids, examples include N-phenylglycine, N-methyl-N-phenylglycine, N-ethyl-N-phenylglycine, etc. Among them, N-phenylglycine is particularly preferred. From the viewpoint of improving the peeling property and / or sensitivity, the content of the N-aryl amino acid in the photosensitive resin composition is preferably 0.05% by mass to 5% by mass, more preferably 0.1% to 2% by mass, relative to the total solid content of the photosensitive resin composition.

[0601] As the organic halogen compound, examples include amyl bromide, isoamyl bromide, isobutene bromide, vinyl bromide, diphenylmethyl bromide, benzyl bromide, dibromomethane, tribromomethyl phenyl sulfone, carbon tetrabromide, tris(2,3-dibromopropyl) phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, and a chlorotriazine compound. Among them, tribromomethyl phenyl sulfone is particularly preferably used. From the viewpoint of improving the peeling property and / or sensitivity, the content of the organic halogen compound in the photosensitive resin composition is preferably 0.05% by mass to 5% by mass, more preferably 0.1% by mass to 3% by mass, relative to the total solid content of the photosensitive resin composition.

[0602] As other photosensitizers, examples include quinones such as 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, and 3-chloro-2-methylanthraquinone; benzoin ethers such as benzoin, benzoin ethyl ether, benzoin phenyl ether, methyl benzoin, and ethyl benzoin; benzil dimethyl ketal, benzil diethyl ketal; and oxime esters such as 1-phenyl-1,2-propanedione-2-O-benzoyl oxime and 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl) oxime. From the viewpoint of improving the peeling property and / or sensitivity, the content of the photosensitizer in the photosensitive resin composition is preferably 0.05% by mass to 5% by mass, more preferably 0.1% by mass to 3% by mass, relative to the total solid content of the photosensitive resin composition.

[0603] In addition, in this third embodiment, the photosensitive resin composition preferably contains a pyrazoline compound as a photosensitizer. As the pyrazoline compound, 1-phenyl-3-(4-tert-butyl-styryl)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-(4-(benzoxazol-2-yl)phenyl)-3-(4-tert-butyl-styryl)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-phenyl-3-(4-biphenyl)-5-(4-tert-butyl-phenyl)-pyrazoline, and 1-phenyl-3-(4-biphenyl)-5-(4-tert-octyl-phenyl)-pyrazoline are preferred.

[0604] (D) Additive

[0605] The photosensitive resin composition may contain additives such as a color-changing agent, a dye, a plasticizer, an antioxidant, and a stabilizer as desired. For example, the additives listed in Japanese Patent Application Laid-Open No. 2013-156369 and International Publication No. 2009 / 093706 can be used.

[0606] Examples of the color-changing agent include a leuco dye and a fluorane dye. The use of the color-changing agent is preferred in terms of the visibility of color development based on the exposed portion. In addition, when a positioning mark for exposure is read by an inspection machine or the like, it is advantageous that the position is easily recognized when the contrast between the exposed portion and the unexposed portion is large.

[0607] Examples of the leuco dye include tris(4-dimethylaminophenyl)methane [leuco crystal violet], bis(4-dimethylaminophenyl)phenylmethane [leuco malachite green], etc. In particular, from the viewpoint of good contrast, leuco crystal violet is preferably used as the leuco dye. The content of the leuco dye in the photosensitive resin composition is preferably 0.1% by mass to 10% by mass. The content is preferably 0.1% by mass or more from the viewpoint of the contrast between the exposed portion and the unexposed portion, and preferably 10% by mass or less from the viewpoint of maintaining storage stability.

[0608] Examples of the basic dye include basic green 1 [CAS No. (the same below): 633-03-4] (for example, Aizen Diamond Green GH, trade name, manufactured by Hodogaya Chemical Co., Ltd.), malachite green oxalate [2437-29-8] (for example, Aizen Malachite Green, trade name, manufactured by Hodogaya Chemical Co., Ltd.), brilliant green [633-03-4], magenta [632-99-5], methyl violet [603-47-4], methyl violet 2B [8004-87-3], crystal violet [548-62-9], methyl green [82-94-0], victoria blue B [2580-56-5], basic blue 7 [2390-60-5] (for example, Aizen Victoria PureBlue BOH, trade name, manufactured by Hodogaya Chemical Co., Ltd.), rhodamine B [81-88-9], rhodamine 6G [989-38-8], basic yellow 2 [2465-27-2], etc. Among them, basic green 1, malachite green oxalate, and basic blue 7 are preferred, and basic green 1 is particularly preferred from the viewpoint of improving hue stability and exposure contrast.

[0609] In this third embodiment, the content of the basic dye in the photosensitive resin composition is preferably in the range of 0.001% by mass to 3% by mass, more preferably in the range of 0.01% by mass to 2% by mass, and still more preferably in the range of 0.01% by mass to 1% by mass. The content of the dye is preferably 0.001% by mass or more from the viewpoint of obtaining good colorability, and preferably 3% by mass or less from the viewpoint of maintaining the sensitivity of the photosensitive resin layer.

[0610] In this third embodiment, in order to suppress the delay in the stripping of the resist pattern caused by the alkali-soluble polymer having a structural unit content of (meth)acrylic acid of 10% by mass to 24% by mass and shorten the stripping time, it is preferable to contain a toluenesulfonamide such as o-toluenesulfonamide or p-toluenesulfonamide as a plasticizer in the photosensitive resin composition. The content of the toluenesulfonamide in the photosensitive resin composition is preferably in the range of 0.1% by mass to 5% by mass, more preferably in the range of 1% by mass to 4% by mass.

[0611] As other plasticizers, for example, glycol esters such as polyethylene glycol, polypropylene glycol, polyoxypropylene polyoxyethylene ether, polyoxyethylene monomethyl ether, polyoxypropylene monomethyl ether, polyoxyethylene polyoxypropylene monomethyl ether, polyoxyethylene monoethyl ether, polyoxypropylene monoethyl ether, and polyoxyethylene polyoxypropylene monoethyl ether can be mentioned; phthalate esters such as diethyl phthalate; tributyl citrate, triethyl citrate, acetyltriethyl citrate, acetyltri-n-propyl citrate, and acetyltri-n-butyl citrate; propylene glycol obtained by adding propylene oxide to both sides of bisphenol A, ethylene glycol obtained by adding ethylene oxide to both sides of bisphenol A, and the like.

[0612] From the viewpoint of the thermal stability or storage stability of the photosensitive resin composition, the photosensitive resin composition preferably contains at least one selected from the group consisting of the following as a stabilizer: radical polymerization inhibitors such as p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, cuprous chloride, 2,6-di-tert-butyl-p-cresol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), diphenylnitrosamine, triethylene glycol-bis(3-3-tert-butyl-5-methyl-4-hydroxyphenylpropionate), and aluminum salt of nitrosophenylhydroxylamine; benzotriazoles such as 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylidene-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylidene-1,2,3-tolyltriazole, 1-(2-dioctylaminomethyl)-benzotriazole, and bis(N-2-hydroxyethyl)aminomethylidene-1,2,3-benzotriazole; carboxybenzotriazoles such as 4-carboxy-1,2,3-benzotriazole, 5-carboxy-1,2,3-benzotriazole, 6-carboxy-1,2,3-benzotriazole, 1:1 mixture of 1-(2-dibutylaminomethyl)-5-carboxybenzotriazole and 1-(2-dibutylaminomethyl)-6-carboxybenzotriazole, N-(N,N-di-2-ethylhexyl)aminomethylidene carboxybenzotriazole, N-(N,N-di-2-hydroxyethyl)aminomethylidene carboxybenzotriazole, and N-(N,N-di-2-ethylhexyl)aminoethylidene carboxybenzotriazole; and epoxyalkane compounds having a glycidyl group such as neopentyl glycol diglycidyl ether (e.g., Epolight 1500NP manufactured by Kyoeisha Chemical Co., Ltd.), nonaethylene glycol diglycidyl ether (e.g., Epolight 400E manufactured by Kyoeisha Chemical Co., Ltd.), bisphenol A-propylene oxide 2 mol adduct diglycidyl ether (e.g., Epolight 3002 manufactured by Kyoeisha Chemical Co., Ltd.), hydrogenated bisphenol A diglycidyl ether (e.g., Epolight 4000 manufactured by Kyoeisha Chemical Co., Ltd.), 1,6-hexanediol diglycidyl ether (e.g., Epolight 1600 manufactured by Kyoeisha Chemical Co., Ltd.).

[0613] In this third embodiment, the total content of all the stabilizers in the photosensitive resin composition is preferably in the range of 0.001% by mass to 3% by mass, more preferably in the range of 0.01% by mass to 1% by mass, and still more preferably in the range of 0.05% by mass to 0.7% by mass. The total content of the stabilizer is preferably 0.001% by mass or more from the viewpoint of imparting good storage stability to the photosensitive resin composition, and preferably 3% by mass or less from the viewpoint of maintaining the sensitivity of the photosensitive resin layer.

[0614] The above-described additives can be used alone or in combination of two or more kinds.

[0615] <Photosensitive resin composition preparation liquid>

[0616] In the present third embodiment, a photosensitive resin composition preparation liquid can be formed by adding a solvent to the photosensitive resin composition. As suitable solvents, ketones such as acetone and methyl ethyl ketone (MEK); and alcohols such as methanol, ethanol, and isopropyl alcohol can be cited. It is preferred to add the solvent to the photosensitive resin composition such that the viscosity of the photosensitive resin composition preparation liquid is 500 mPa·s to 4000 mPa·s at 25°C.

[0617] <Photosensitive resin laminate>

[0618] In the present third embodiment, a photosensitive resin laminate having a support and a photosensitive resin layer laminated on the support and formed of the above-described photosensitive resin composition can be provided. The photosensitive resin laminate may also have a protective layer on the side opposite to the support side of the photosensitive resin layer as desired.

[0619] The support is not particularly limited, and a transparent support that transmits light emitted from a self-exposure light source is preferred. As such a support, for example, polyethylene terephthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, polymethyl methacrylate copolymer film, polystyrene film, polyacrylonitrile film, styrene copolymer film, polyamide film, and cellulose derivative film can be cited. These films can also be stretched as needed. The haze is preferably 0.01% to 5.0%, more preferably 0.01% to 2.5%, and further preferably 0.01% to 1.0%. Regarding the thickness of the film, the thinner the film, the more advantageous it is in terms of image formability and economy, but since the strength needs to be maintained, it is preferably 10 μm to 30 μm.

[0620] In addition, an important characteristic of the protective layer used in the photosensitive resin laminate is that the adhesion of the protective layer to the photosensitive resin layer is smaller than the adhesion of the support to the photosensitive resin layer, and it can be easily peeled off. As the protective layer, for example, polyethylene film, polypropylene film, etc. are preferred. For example, a film having excellent peelability described in Japanese Patent Laid-Open No. 59-202457 can be used. The film thickness of the protective layer is preferably 10 μm to 100 μm, more preferably 10 μm to 50 μm.

[0621] In this third embodiment, the thickness of the photosensitive resin layer in the photosensitive resin laminate is preferably 5 μm to 100 μm, more preferably 7 μm to 60 μm. The smaller the thickness of the photosensitive resin layer, the higher the resolution of the resist pattern. On the other hand, the greater the thickness of the photosensitive resin layer, the higher the strength of the cured film. Therefore, it can be selected according to the use.

[0622] As a method for producing a photosensitive resin laminate by sequentially laminating a support, a photosensitive resin layer, and a protective layer according to desire, a known method can be used.

[0623] For example, the above-mentioned photosensitive resin composition formulation liquid is prepared, and then it is coated on a support using a bar coater or a roll coater and dried, and a photosensitive resin layer formed from the photosensitive resin composition formulation liquid is laminated on the support. Further, a protective layer is laminated on the photosensitive resin layer according to desire, whereby a photosensitive resin laminate can be produced.

[0624] <Resist Pattern Forming Method>

[0625] The method for forming a resist pattern preferably sequentially includes: a lamination step of laminating a photosensitive resin layer formed from the above-mentioned photosensitive resin composition on a support, an exposure step of exposing the photosensitive resin layer, and a development step of developing the exposed photosensitive resin layer. In this third embodiment, an example of a specific method for forming a resist pattern is shown below.

[0626] First, in the lamination step, a photosensitive resin layer is formed on a substrate using a laminator. Specifically, when the photosensitive resin laminate has a protective layer, after peeling off the protective layer, the photosensitive resin layer is heat-pressed onto the substrate surface using a laminator for lamination. Examples of the material of the substrate include copper, stainless steel (SUS), glass, indium tin oxide (ITO), etc.

[0627] In this third embodiment, the photosensitive resin layer can be laminated only on one side of the substrate surface, or laminated on both sides as needed. The heating temperature during lamination is usually 40°C to 160°C. In addition, by performing the heat pressing during lamination two or more times, the adhesion of the obtained resist pattern to the substrate can be improved. When performing heat pressing, a two-stage laminator equipped with a double roll can be used, or the laminate of the substrate and the photosensitive resin layer can be repeatedly passed through a roll several times for pressing.

[0628] Next, in the exposure process, a photosensitive resin layer is exposed to actinic light using an exposure machine. The exposure can be performed after peeling off the support as desired. When performing exposure through a photomask, the exposure amount is determined by the illuminance of the light source and the exposure time, and a light meter can be used to measure it. In the exposure process, direct imaging exposure can also be performed. In direct imaging exposure, exposure is performed on the substrate using a direct drawing device without using a photomask. As the light source, a semiconductor laser or an ultra-high pressure mercury lamp with a wavelength of 350 nm to 410 nm is used. When the pattern drawing is controlled by a computer, the exposure amount is determined by the illuminance of the exposure light source and the moving speed of the substrate.

[0629] Next, in the development process, an undeveloped portion or a developed portion in the photosensitive resin layer after exposure is removed using a developer with a developing device. After exposure, if there is a support on the photosensitive resin layer, it is removed. Next, using a developer formed from an aqueous alkali solution, the undeveloped portion or the developed portion is developed and removed to obtain a resist image.

[0630] As the aqueous alkali solution, an aqueous solution of Na 2 CO 3 , K 2 CO 3 , etc. is preferred. The aqueous alkali solution is selected according to the characteristics of the photosensitive resin layer, and an aqueous solution of Na 2 CO 3 with a concentration of 0.2% by mass to 2% by mass is usually used. In the aqueous alkali solution, a surfactant, an antifoaming agent, a small amount of organic solvent for promoting development, etc. can also be mixed. The temperature of the developer in the development process is preferably kept constant in the range of 20°C to 40°C.

[0631] Through the above process, a resist pattern can be obtained, and a heating process can also be further performed at 100°C to 300°C as desired. By implementing this heating process, the chemical resistance of the resist pattern can be improved. In the heating process, a heating furnace using hot air, infrared rays, or far-infrared rays can be used.

[0632] The photosensitive resin composition of this third embodiment can be suitably used for forming a circuit of a printed circuit board. Generally, as a method for forming a circuit of a printed circuit board, a subtractive method and a semi-additive method (SAP) are used.

[0633] The subtractive method is a method of forming a circuit by etching only the non-circuit portion from a conductor disposed on the entire surface of the substrate.

[0634] SAP is a method of forming only the circuit portion by plating after forming a resist on the non-circuit portion on a conductor seed layer disposed on the entire surface of the substrate.

[0635] <Manufacturing method of conductor pattern>

[0636] The manufacturing method of the conductor pattern preferably sequentially includes: a lamination step of laminating a photosensitive resin layer formed of the above photosensitive resin composition on a substrate such as a metal plate or a metal film insulating plate; an exposure step of exposing the photosensitive resin layer; a development step of removing the unexposed portion or the exposed portion of the exposed photosensitive resin layer with a developer to obtain a substrate having a resist pattern formed thereon; and a conductor pattern forming step of etching or plating the substrate having the resist pattern formed thereon.

[0637] In this third embodiment, the manufacturing method of the conductor pattern is carried out as follows: A metal plate or a metal film insulating plate is used as the substrate, and a resist pattern is formed by the above resist pattern forming method, and then through the conductor pattern forming step, thus carried out. In the conductor pattern forming step, a conductor pattern is formed on the substrate surface (for example, copper surface) exposed by development using a known etching method or plating method.

[0638] Furthermore, this third embodiment is applicable to, for example, the following uses.

[0639] <Manufacturing method of circuit board>

[0640] After manufacturing the conductor pattern by the manufacturing method of the conductor pattern, a stripping step of stripping the resist pattern from the substrate using an aqueous solution having a stronger alkalinity than the developer is further carried out, so that a circuit board (for example, a printed circuit board) having a desired wiring pattern can be obtained.

[0641] Regarding the alkaline aqueous solution for stripping (hereinafter also referred to as "stripping solution"), there is no particular limitation, and an aqueous solution of NaOH or KOH having a concentration of 2% by mass to 5% by mass or an organic amine-based stripping solution is usually used. A small amount of a water-soluble solvent can be added to the stripping solution. As the water-soluble solvent, for example, alcohol etc. can be cited. The temperature of the stripping solution in the stripping step is preferably in the range of 40°C to 70°C.

[0642] <Manufacture of lead frame>

[0643] A metal plate such as copper, copper alloy, or iron-based alloy is used as the substrate, and a resist pattern is formed by the resist pattern forming method, and then through the following steps, a lead frame can be manufactured. First, a step of etching the substrate exposed by development to form a conductor pattern is carried out. Then, a stripping step of stripping the resist pattern is carried out by the same method as the manufacturing method of the circuit board, and a desired lead frame can be obtained.

[0644] <Manufacture of a substrate having a concavo-convex pattern>

[0645] The resist pattern formed by the resist pattern forming method can be used as a protective mask member when processing a substrate by a sandblasting method. At this time, examples of the substrate include glass, silicon wafers, amorphous silicon, polycrystalline silicon, ceramics, sapphire, metal materials, etc. A resist pattern is formed on these substrates by the same method as the resist pattern forming method. Then, a sandblasting treatment step of blowing abrasive from above the formed resist pattern and cutting to a target depth, and a stripping step of removing the resist pattern portion remaining on the substrate from the substrate with an alkali stripping solution or the like are performed, and a base material having a fine concavo-convex pattern on the substrate can be manufactured.

[0646] In the sandblasting treatment step, known abrasives can be used. For example, abrasives usually containing SiC, SiO 2 , Al 2 O 3 , CaCO 3 , ZrO, glass, stainless steel, etc., with particle sizes of 2 μm to 100 μm are used.

[0647] <Manufacture of semiconductor packages>

[0648] Using a wafer on which a large-scale integrated circuit (LSI) has been formed as the substrate, after forming a resist pattern on the wafer by the resist pattern forming method, through the following steps, a semiconductor package can be manufactured. First, a step of forming a conductor pattern by applying columnar plating of copper, solder, etc. to the openings exposed by development is performed. Then, a stripping step of stripping the resist pattern by the same method as the manufacturing method of the circuit board is performed. Furthermore, a step of removing the thin metal layer other than the columnar plating by etching is performed, and a desired semiconductor package can be obtained.

[0649] In this third embodiment, the photosensitive resin composition can be used for the manufacture of printed circuit boards; the manufacture of lead frames for mounting IC chips; precision machining of metal foils such as metal mask manufacture; the manufacture of packages such as ball grid arrays (BGAs) and chip scale packages (CSPs); the manufacture of tape substrates such as chip-on-film (COF) and tape automated bonding (TAB); the manufacture of semiconductor bumps; and the manufacture of partition walls of flat panel displays such as ITO electrodes, addressing electrodes, and electromagnetic wave shielding.

[0650] It should be noted that regarding the values of the above parameters, unless otherwise specified, they are measured according to the measurement methods in the examples described later.

[0651] <Fourth Embodiment>

[0652] Hereinafter, a mode for implementing the fourth embodiment of the present invention (hereinafter simply referred to as "this fourth embodiment") will be specifically described.

[0653] <Photosensitive resin composition>

[0654] In this fourth embodiment, the photosensitive resin composition contains (A) an alkali-soluble polymer, (B) an ethylenically unsaturated bond-containing compound, and (C) a photopolymerization initiator. If desired, the photosensitive resin composition further contains other components such as (D) a stabilizer.

[0655] It should be noted that in this specification, "(meth)acrylic acid" means acrylic acid or methacrylic acid, "(meth)acryloyl" means acryloyl or methacryloyl, and "(meth)acrylate" means "acrylate" or "methacrylate".

[0656] [(A) Alkali-soluble polymer]

[0657] From the viewpoints of extending the resolution and the minimum development time, the aforementioned (A) alkali-soluble polymer contains a first copolymer in which the content ratio of acid monomer units is less than 25% by mass and the content ratio of aromatic monomer units is 30% by mass or more. The first copolymer may also contain other monomer units based on the acid monomer units and aromatic monomer units if desired. The dispersity of the copolymer represented by the ratio of the weight average molecular weight (described later) to the number average molecular weight of the copolymer is preferably 1 or more and 6 or less.

[0658] Examples of the acid monomer include (meth)acrylic acid, pentenoic acid, unsaturated dicarboxylic anhydride, hydroxystyrene, etc. Examples of the unsaturated dicarboxylic anhydride include maleic anhydride, itaconic anhydride, fumaric acid, citraconic anhydride, etc. Among them, (meth)acrylic acid is preferred.

[0659] As the copolymerization ratio of the acid monomer units in the aforementioned (A) component, relative to the total mass of all monomer units, it is preferably less than 25% by mass, more preferably 10% to 24% by mass, and further preferably 15% to 23% by mass. When the content ratio of the acid monomer units is within this range, it is preferred from the viewpoints of improving the resolution and extending the minimum development time.

[0660] Aromatic monomers are also called unsaturated aromatic compounds. Examples of the aromatic monomer include styrene, α-methylstyrene, vinylnaphthalene, etc.; (meth)acrylic acid aralkyl esters, etc. Examples of the (meth)acrylic acid aralkyl ester include (meth)acrylic acid benzyl ester, etc.

[0661] As the copolymerization ratio of the aromatic monomer units (preferably styrene units) in the aforementioned component (A), it is preferably 30% by mass or more, more preferably 32% to 60% by mass, and still more preferably 35% to 55% by mass, based on the total mass of all the monomer units. When the copolymerization ratio of the aromatic monomer having high hydrophobicity and being difficult to be compatible with the developer and the developer cleaning water is set within the above range, it is preferable from the viewpoints of improving the resolution and extending the minimum development time.

[0662] As other monomers, for example, (meth)acrylic acid alkyl esters, conjugated diene compounds, polar monomers, crosslinkable monomers, etc. can be mentioned.

[0663] (Meth)acrylic acid alkyl esters is a concept including both linear alkyl esters and cyclic alkyl esters. Specifically, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, n-tetradecyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, etc. can be mentioned.

[0664] As the conjugated diene compound, for example, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 2-phenyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, etc. can be mentioned.

[0665] As the polar monomer, for example, it can be mentioned:

[0666] Hydroxyl group-containing monomers such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, pentenol; amino group-containing monomers such as 2-aminoethyl methacrylate;

[0667] Amide group-containing monomers such as (meth)acrylamide, N-hydroxymethyl (meth)acrylamide;

[0668] Cyano group-containing monomers such as acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-cyanoethyl acrylate;

[0669] Epoxy group-containing monomers such as glycidyl (meth)acrylate, 3,4-epoxycyclohexyl (meth)acrylate;

[0670] etc.

[0671] Examples of the crosslinkable monomer include trimethylolpropane triacrylate, divinylbenzene, and the like.

[0672] The first copolymer is particularly preferably a copolymer of (meth)acrylic acid, styrene, and other monomers.

[0673] In the fourth embodiment, from the viewpoints of resolution, developability, and aggregability, a second copolymer in which the content ratio of the aromatic monomer unit described above is 45% by mass to 90% by mass is also preferable. In the second copolymer, when the content ratio of the aromatic monomer unit is 45% by mass, there is a tendency to ensure the hydrophobicity of the resist pattern containing the second copolymer. In addition, when the weight ratio of the second copolymer is 25% by mass or more with respect to the total weight of all the copolymers, it is preferable from the viewpoint of improving aggregability.

[0674] The second copolymer may also contain the acid monomer unit and other monomer units described above. As the aromatic monomer for polymerizing the second copolymer, styrene is preferable from the viewpoint of hydrophobicity. From the viewpoint of developability, the upper limit of the content ratio of the aromatic monomer unit in the second copolymer is more preferably 80% by mass or 70% by mass.

[0675] The second copolymer may contain the acid monomer unit and other monomer units described above. From the viewpoints of resolution, developability, and aggregability, the content ratio of the acid monomer unit described above is preferably 25% by mass to 50% by mass, more preferably 25% by mass to 40% by mass. As the acid monomer for polymerizing the second copolymer, (meth)acrylic acid is preferable from the viewpoint of developability.

[0676] The weight average molecular weight of the component (A) (when the component (A) contains a plurality of copolymers, the weight average molecular weight of the whole mixture) is preferably 5,000 to 1,000,000, more preferably 10,000 to 500,000, and still more preferably 15,000 to 100,000. When the weight average molecular weight of the component (A) is adjusted within this range, it is preferable from the viewpoint of making the development time during the formation of the resist pattern suitable for the operating state of the production line used.

[0677] In the fourth embodiment, the content of the component (A) in the photosensitive resin composition is preferably 10% by mass to 90% by mass, more preferably 20% by mass to 80% by mass, and still more preferably 40% by mass to 60% based on the total solid content of the photosensitive resin composition (hereinafter, the same applies to each contained component unless otherwise specified). This content is preferably 10% by mass or more from the viewpoint of maintaining alkali developability, and on the other hand, is preferably 90% by mass or less from the viewpoint of allowing the resist pattern formed by exposure to fully exhibit the performance as a resist.

[0678] The content ratio of the acid monomer unit is less than 25% by mass, and the content ratio of the aromatic monomer unit is 30% by mass or more. The first copolymer is preferably 5% by mass or more and 50% by mass or less based on the total solid content of the photosensitive resin composition. More preferably, it is 10% by mass or more and 40% by mass or less.

[0679] [(B) Olefinically unsaturated bond-containing compound]

[0680] (B) The olefinically unsaturated bond-containing compound is a compound having polymerizability by having an olefinically unsaturated group in its structure. From the viewpoint of addition polymerizability, the olefinically unsaturated bond is preferably a terminal olefinically unsaturated group.

[0681] In this fourth embodiment, when (A) the alkali-soluble polymer and (B) the olefinically unsaturated bond-containing compound are used in combination, from the viewpoints of ensuring good resolution of the resist pattern and extending the minimum development time, the weight average molecular weight of (B) the olefinically unsaturated bond-containing compound is preferably 900 or less. In this specification, regarding the average molecular weight of (B) the olefinically unsaturated bond-containing compound, when (B) the olefinically unsaturated bond-containing compound is a single kind, it means the weight average molecular weight derived from the structural formula of the single kind of olefinically unsaturated bond-containing compound, and when (B) the olefinically unsaturated bond-containing compound is composed of a plurality of kinds, it means the weighted average of the weight average molecular weights of the respective olefinically unsaturated bond-containing compounds and the compounding ratios.

[0682] (B) From the viewpoints of improving resolution and extending the minimum development time, the weight average molecular weight of the olefinically unsaturated bond-containing compound is more preferably 850 or less, further preferably 800 or less, and from the viewpoint of suppressing the edge fusion property of the photosensitive resin laminate, it is preferably 50 or more, more preferably 100 or more. Here, the edge fusion property means the phenomenon that the photosensitive resin composition layer oozes out from the end face of the roll when the photosensitive resin laminate is wound into a roll shape.

[0683] (B) The olefinically unsaturated bond-containing compound may contain at least one selected from the group consisting of the following (b 1 ) to (b 6 ):

[0684] (b 1 ) The ethylene glycol di(meth)acrylate compound represented by the following general formula (I):

[0685]

[0686] {In the formula, R 1 and R 2 each independently represent a hydrogen atom or a methyl group, and m 1 is a number satisfying 2 to 40.};

[0687] (b 2 ) The epoxyalkane-modified bisphenol A di(meth)acrylate compound represented by the following general formula (II):

[0688]

[0689] {In the formula, R 3 and R 4 each independently represent a hydrogen atom or a methyl group, A is C 2 H 4 , B is C 3 H 6 , n 1 , n 2 , n 3 and n 4 are integers satisfying the relationship of n 1 + n 2 + n 3 + n 4 = 2 to 50. The arrangement of the repeating units of -(A-O)- and -(B-O)- can be random or block. In the case of block, either -(A-O)- or -(B-O)- is optionally on the biphenyl side.};

[0690] (b 3 ) The tri(meth)acrylate compound represented by the following general formula (III):

[0691]

[0692] {In the formula, R 5 to R 7 each independently represent a hydrogen atom or a methyl group, X represents an alkylene group having 2 to 6 carbon atoms, m 2 , m 3 and m 4 are each independently an integer from 0 to 40, m 2 + m 3 + m 4 is from 0 to 40, and when m 2 + m 3 + m 4 is 2 or more, the plurality of Xs are optionally the same or different from each other};

[0693] (b 4 ) The urethane di(meth)acrylate compound represented by the following general formula (IV):

[0694]

[0695] {In the formula, R 8 and R 9Each independently represents a hydrogen atom or a methyl group, Y represents an alkylene group having 2 to 6 carbon atoms, Z represents a divalent organic group, and s and t are each independently an integer from 0 to 40, and s + t ≥ 1};

[0696] (b 5 ) A tetra(meth)acrylate compound represented by the following general formula (XI):

[0697]

[0698] {In the formula, R 5 ~R 8 Each independently represents a hydrogen atom or a methyl group, X represents an alkylene group having 2 to 6 carbon atoms, m 2 , m 3 , m 4 and m 5 Each independently is an integer from 0 to 40, m 2 +m 3 +m 4 +m 5 is from 0 to 50, and when m 2 +m 3 +m 4 +m 5 is 2 or more, the plurality of Xs are optionally the same as or different from each other}; and

[0699] (b 6 ) An addition polymerizable monomer other than the above (b 1 ) to (b 5 ).

[0700] From the viewpoint of adjusting the peeling time of the resist pattern and the size of the peeling sheet, the (B) ethylenically unsaturated bond-containing compound preferably contains (b 1 ) the ethylene glycol di(meth)acrylate compound represented by the general formula (I).

[0701] In the general formula (I), m 1 is preferably 2 or more from the viewpoints of peeling time and peeling sheet size, and preferably 40 or less from the viewpoints of resolution, plating resistance, and etching resistance. m 1 is more preferably 4 to 20, and further preferably 6 to 12.

[0702] As specific examples of the ethylene glycol di(meth)acrylate compound represented by the general formula (I), tetraethylene glycol di(meth)acrylate with m 1 = 4, nonaethylene glycol di(meth)acrylate with m 1 = 9, or polyethylene glycol di(meth)acrylate with m 1 = 14 are preferred.

[0703] From the viewpoint of suppressing the generation of aggregates during the development of the photosensitive resin layer formed from the photosensitive resin composition, the (B) ethylenically unsaturated bond-containing compound preferably contains (b 2 ) an alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the general formula (II). B in the general formula (II) may be -CH 2 CH 2 CH 2 - or -CH(CH 3 )CH 2 -.

[0704] The hydrogen atoms on the aromatic ring in the general formula (II) may be substituted with heteroatoms and / or substituents.

[0705] Examples of the heteroatom include a halogen atom, etc., and examples of the substituent include an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aryl group having 6 to 18 carbon atoms, benzoylmethyl, an amino group, an alkylamino group having 1 to 10 carbon atoms, a dialkylamino group having 2 to 20 carbon atoms, a nitro group, a cyano group, a carbonyl group, a mercapto group, an alkylthio group having 1 to 10 carbon atoms, an aryl group, a hydroxyl group, a hydroxyalkyl group having 1 to 20 carbon atoms, a carboxyl group, a carboxyalkyl group having 1 to 10 carbon atoms in the alkyl group, an acyl group having 1 to 10 carbon atoms in the alkyl group, an alkoxy group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 1 to 20 carbon atoms, an alkylcarbonyl group having 2 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an N-alkylcarbamoyl group having 2 to 10 carbon atoms or a heterocyclic group-containing group, or an aryl group substituted with these substituents, etc. These substituents may form a fused ring, or the hydrogen atoms in these substituents may be substituted with heteroatoms such as halogen atoms. When the aromatic ring in the general formula (II) has a plurality of substituents, the plurality of substituents may be the same or different.

[0706] R in the general formula (II) 3 and R 4 are each independently a hydrogen atom or a methyl group. From the viewpoint of ensuring the contrast immediately after exposure of the photosensitive resin layer formed from the photosensitive resin composition, it is preferred that one or both of R 3 and R 4 are hydrogen atoms, and more preferably both R 3 and R 4 are hydrogen atoms.

[0707] From the viewpoints of improving the resolution and extending the minimum development time, it is preferred that a shorter-chain alkylene oxide is added to the alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the general formula (II). More specifically, in the general formula (II), n 2 , n 1 , n 2 , n 3 and n 4 preferably satisfy n 1+n 2 +n 3 +n 4 = a relationship of 0 to 30, more preferably satisfying n 1 +n 2 +n 3 +n 4 = a relationship of 0 to 25, further preferably satisfying n 1 +n 2 +n 3 +n 4 = a relationship of 0 to 20, particularly preferably satisfying n 1 +n 2 +n 3 +n 4 = a relationship of 0 to 10.

[0708] From the viewpoints of improving the resolution and extending the minimum development time, 40 mass% or more of the (B) ethylenically unsaturated bond-containing compound is preferably (b 2 ) an alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the general formula (II), more preferably the n in the general formula (II) 1 , n 2 , n 3 and n 4 satisfy n 1 +n 2 +n 3 +n 4 = a relationship of 0 to 20 of the alkylene oxide-modified bisphenol A di(meth)acrylate compound. More preferably, 50 mass% of the (B) ethylenically unsaturated bond-containing compound, further preferably 55 mass% or more, and most preferably 60 mass% is (b 2 ) an alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the general formula (II).

[0709] As (b 2)Preferred specific examples of the alkylene oxide-modified bisphenol A type di(meth)acrylate compound represented by the general formula (II) include di(meth)acrylate of polyethylene glycol obtained by adding an average of 1 unit of ethylene oxide to both ends of bisphenol A, di(meth)acrylate of polyethylene glycol obtained by adding an average of 2 units of ethylene oxide to both ends of bisphenol A, di(meth)acrylate of polyethylene glycol obtained by adding an average of 5 units of ethylene oxide to both ends of bisphenol A, di(meth)acrylate of polyethylene glycol obtained by adding an average of 7 units of ethylene oxide to both ends of bisphenol A, di(meth)acrylate of polyalkylene glycol obtained by adding an average of 6 units of ethylene oxide and an average of 2 units of propylene oxide to both ends of bisphenol A, di(meth)acrylate of polyalkylene glycol obtained by adding an average of 15 units of ethylene oxide to both ends of bisphenol A, di(meth)acrylate of polyalkylene glycol obtained by adding an average of 15 units of ethylene oxide and an average of 2 units of propylene oxide to both ends of bisphenol A, and the like.

[0710] In the general formula (II), from the viewpoint of improving the resolution, n 1 , n 2 , n 3 and n 4 also preferably satisfy the relationship of n 1 +n 2 +n 3 +n 4 =2 to 20, and particularly preferably satisfy the relationship of n 1 +n 2 +n 3 +n 4 =2 to 10.

[0711] From the viewpoints of improving the resolution and prolonging the minimum development time, it is particularly preferred that the (B) ethylenically unsaturated bond-containing compound contains simultaneously: a compound in the general formula (II) that satisfies n 1 +n 2 +n 3 +n 4 =2 to 20, a compound in the general formula (II) in which one or both of R 3 and R 4 are methyl, and a compound in the general formula (II) that satisfies n 1 +n 2 +n 3 +n 4 =2 to 16.

[0712] From the viewpoint of suppressing the generation of aggregates during the development of the photosensitive resin layer formed from the photosensitive resin composition, the (B) ethylenically unsaturated bond-containing compound preferably contains (b 3The tri(meth)acrylate compound represented by the general formula (III). In the general formula (III), X is an alkylene group having 2 to 6 carbon atoms, and examples thereof may be -CH 2 CH 2 -, -CH 2 CH 2 CH 2 -, -CH(CH 3 )CH 2 - and the like.

[0713] From the viewpoint of resolution, (b 3 ) The tri(meth)acrylate compound represented by the general formula (III) preferably has an alkylene oxide moiety with a shorter chain. More specifically, in the general formula (III), m 2 +m 3 +m 4 is preferably 8 to 40, more preferably 9 to 25.

[0714] As a preferred specific example of (b 3 ) The tri(meth)acrylate compound represented by the general formula (III), examples thereof include ethylene oxide (EO) modified trimethylolpropane tri(meth)acrylate (average addition mole number of EO: 1 to 40), propylene oxide (PO) modified trimethylolpropane tri(meth)acrylate (average addition mole number of PO: 1 to 40), and the like.

[0715] From the viewpoint of resolution, (B) The ethylenically unsaturated bond-containing compound preferably contains (b 4 ) The urethane di(meth)acrylate compound represented by the general formula (IV).

[0716] In the general formula (IV), Z represents a divalent organic group, and examples thereof may be an alkylene group having 1 to 10 carbon atoms, an alkylene oxide group having 2 to 10 carbon atoms, a divalent alicyclic group having 3 to 10 carbon atoms optionally having a substituent, and the like.

[0717] In the general formula (IV), Y represents an alkylene group having 2 to 6 carbon atoms, and examples thereof may be -CH 2 CH 2 -, -CH 2 CH 2 CH 2 -, -CH(CH 3 )CH 2 - and the like.

[0718] From the viewpoint of further improving the resolution, it is also preferred that the -(Y-O) s - moiety and the -(Y-O) t - moiety in the general formula (IV) are each independently replaced by -(C 2 H 5 O)-(C3 H 6 O) 9 - Replacement.

[0719] As (b 4 ) Preferred specific examples of the urethane di(meth)acrylate compounds represented by the general formula (IV) include the addition reaction products of (meth)acrylic monomers having a hydroxyl group at the β-position and diisocyanate compounds such as isophorone diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, and 1,6-hexamethylene diisocyanate, tris((meth)acryloyloxy tetraethylene glycol isocyanate) hexamethylene isocyanurate, EO-modified urethane di(meth)acrylate, and EO, PO-modified urethane di(meth)acrylate. It should be noted that EO represents ethylene oxide, and the EO-modified compound has a block structure of ethylene oxide groups. In addition, PO represents propylene oxide, and the PO-modified compound has a block structure of propylene oxide groups. As the EO-modified urethane di(meth)acrylate, for example, the product with the trade name "UA-11" manufactured by Shin-Nakamura Chemical Co., Ltd. can be cited. In addition, as the EO, PO-modified urethane di(meth)acrylate, for example, the product with the trade name "UA-13" manufactured by Shin-Nakamura Chemical Co., Ltd. can be cited. They can be used alone or in combination of two or more.

[0720] From the viewpoint of suppressing the generation of aggregates during the development of the photosensitive resin layer formed from the photosensitive resin composition, the (B) ethylenically unsaturated bond-containing compound preferably contains (b 5 ) the tetra(meth)acrylate compound represented by the general formula (XI).

[0721] In the general formula (XI), X is an alkylene group having 2 to 6 carbon atoms, and can be, for example, -CH 2 CH 2 -, -CH 2 CH 2 CH 2 -, -CH(CH 3 )CH 2 -, etc.

[0722] As (b 5 ) Preferred specific examples of the tetra(meth)acrylate compound represented by the general formula (XI) include pentaerythritol tetra(meth)acrylate, pentaerythritol (poly)alkoxy tetra(meth)acrylate, etc.

[0723] (B) The ethylenically unsaturated bond-containing compound may contain an addition polymerizable monomer other than the components (b 1 ) to (b 5 ) as the component (b 6 ).

[0724] As the (b 6 ) component, the following substances can be listed:

[0725] Tris(meth)acrylates other than the (b 3 ) component, such as trimethylolpropane tris(meth)acrylate, ethoxylated glycerol tris(meth)acrylate, ethoxylated isocyanuric acid tris(meth)acrylate, pentaerythritol tris(meth)acrylate, etc.;

[0726] Tetra(meth)acrylates other than the (b 5 ) component, such as ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, etc.; Penta(meth)acrylates, such as dipentaerythritol penta(meth)acrylate, etc.;

[0727] Hexa(meth)acrylates, such as dipentaerythritol hexa(meth)acrylate, hexa(meth)acrylate obtained by adding a total of 1 to 24 moles of ethylene oxide to 6 terminals of dipentaerythritol, hexa(meth)acrylate obtained by adding a total of 1 to 10 moles of ε-caprolactone to 6 terminals of dipentaerythritol, etc.;

[0728] Acrylate compounds having one (meth)acryloyl group;

[0729] Compounds obtained by reacting a polyol with an α,β-unsaturated carboxylic acid;

[0730] Compounds obtained by reacting a glycidyl group-containing compound with an α,β-unsaturated carboxylic acid; and

[0731] Phthalic acid-based compounds, such as γ-chloro-2-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate and β-hydroxyalkyl-β'-(meth)acryloyloxyalkyl-phthalate, etc.

[0732] In this fourth embodiment, from the viewpoints of the edge fusion property and the adhesion of the photosensitive resin laminate, the total content of all (B) ethylenically unsaturated bond-containing compounds in the photosensitive resin composition is preferably in the range of 1% by mass to 70% by mass, more preferably 2% by mass to 60% by mass, and still more preferably 4% by mass to 50% by mass.

[0733] [(C) Photoinitiator]

[0734] The (C) component is a component that generates radicals capable of initiating the polymerization of the aforementioned (B) component upon irradiation with light.

[0735] As such a component (C), for example, an aromatic ketone compound, a quinone compound, a benzoin ether compound, a benzoin compound, a benzil compound, a hexarylbisimidazole compound, an acridine compound, etc. can be used. Among them, from the viewpoints of high resolution and good hole covering property, it is preferable to use one or more selected from hexarylbisimidazole compounds and acridine compounds. Further, from the viewpoint of the sensitivity of the photosensitive resin composition, the component (C) preferably contains an acridine compound.

[0736] As the above-mentioned hexaarylbiimidazole compounds, for example, 2-(o-chlorophenyl)-4,5-diphenylimidazolyl dimer, 2,2’,5-tris-(o-chlorophenyl)-4-(3,4-dimethoxyphenyl)-4’,5’-diphenylimidazolyl dimer, 2,4-bis-(o-chlorophenyl)-5-(3,4-dimethoxyphenyl)-diphenylimidazolyl dimer, 2,4,5-tris-(o-chlorophenyl)-diphenylimidazolyl dimer, 2-(o-chlorophenyl)-bis-4,5-(3,4-dimethoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2-fluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3-difluoromethylphenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,4-difluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,5-difluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,6-difluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,4-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,5-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,6-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,4,5-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,4,6-trifluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,4,5-tetrafluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,4,6-tetrafluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, 2,2’-bis-(2,3,4,5,6-pentafluorophenyl)-4,4’,5,5’-tetrakis-(3-methoxyphenyl)-imidazolyl dimer, etc. can be cited.

[0737] In addition, as the above-mentioned acridine compounds, for example, the following can be cited:

[0738] Acridine, 9-phenylacridine, 1,6-bis(9-acridinyl)hexane, 1,7-bis(9-acridinyl)heptane, 1,8-bis(9-acridinyl)octane, 1,9-bis(9-acridinyl)nonane, 1,10-bis(9-acridinyl)decane, 1,11-bis(9-acridinyl)undecane, 1,12-bis(9-acridinyl)dodecane, etc.

[0739] The content of the component (C) in the photosensitive resin composition of this fourth embodiment is preferably in the range of 0.1% by mass to 2% by mass, more preferably in the range of 0.2% by mass to 1.8% by mass, still more preferably in the range of 0.3% by mass to 1.7% by mass, and particularly preferably in the range of 0.4% by mass to 1.6% by mass. When the content of the component (C) is set within this range, it is preferable from the viewpoint of obtaining good sensitivity and stripping characteristics.

[0740] From the viewpoint of improving sensitivity and resolution, the component (C) may further contain a sensitizer. Examples of such sensitizers include N-aryl amino acids, organic halogen compounds, and other sensitizers.

[0741] Respectively, examples of the above N-aryl amino acids include:

[0742] N-phenylglycine, N-methyl-N-phenylglycine, N-ethyl-N-phenylglycine, etc.;

[0743] Examples of the organic halogen compounds include:

[0744] Amyl bromide, isoamyl bromide, isobutene bromide, ethylene bromide, diphenylmethyl bromide, benzyl bromide, dibromomethane, tribromomethyl phenyl sulfone, carbon tetrabromide, tris(2,3-dibromopropyl) phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, chlorotriazine compounds, etc.

[0745] Examples of the above other sensitizers include:

[0746] Quinone compounds such as 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, 3-chloro-2-methylanthraquinone, etc.;

[0747] Aromatic ketone compounds such as benzophenone, Michler's ketone [4,4'-bis(dimethylamino)benzophenone], 4,4'-bis(diethylamino)benzophenone, etc.;

[0748] Benzoin ether compounds such as benzoin, benzoin ethyl ether, benzoin phenyl ether, methyl benzoin, ethyl benzoin, etc.

[0749] Oxime ester compounds such as benzil dimethyl ketal, benzil diethyl ketal, 1-phenyl-1,2-propanedione-2-O-benzoyl oxime, 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl) oxime;

[0750] etc.

[0751] From the viewpoints of the sensitivity of the composition and the peelability of the cured film of the resist, the content of the sensitizer in this fourth embodiment is preferably 0.01% by mass to 5% by mass, more preferably 0.05% by mass to 3% by mass, and further preferably 0.1% by mass to 2% by mass.

[0752] It should be noted that in the photosensitive resin composition of this fourth embodiment, when an acridine compound and an N-aryl amino acid are used as the component (C) and they are used in combination within the above-mentioned usage ratio range, it is preferable from the viewpoints of suppressing the etching rate and the aspect ratio difference of the wiring width when forming a conductor pattern.

[0753] [(D) Stabilizer]

[0754] The photosensitive resin composition may contain a stabilizer as desired. In this fourth embodiment, from the viewpoint of improving the resolution, a hindered phenol is preferably used as the stabilizer. Generally, a hindered phenol refers to a phenol with a large steric hindrance. The photosensitive resin composition contains a compound represented by the following general formula (V) as the hindered phenol:

[0755]

[0756] {In the formula, R 51 represents an optionally substituted linear alkyl group, branched alkyl group, aryl group, cyclohexyl group, linear alkyl group sandwiching a divalent linking group, branched alkyl group sandwiching a divalent linking group, cyclohexyl group sandwiching a divalent linking group, or aryl group sandwiching a divalent linking group, and R 52 , R 53 and R 54 each independently represent hydrogen, or an optionally substituted linear alkyl group, branched alkyl group, aryl group, cyclohexyl group, linear alkyl group sandwiching a divalent linking group, branched alkyl group sandwiching a divalent linking group, cyclohexyl group sandwiching a divalent linking group, or aryl group sandwiching a divalent linking group.}.

[0757] The compound represented by the general formula (V) is excellent in terms of improving the resolution of the photosensitive resin composition and suppressing the decrease in the sensitivity of the photosensitive resin composition. It should be noted that the compound represented by the general formula (V) does not have two or more phenolic hydroxyl groups on one aromatic ring, and has a substituent only at one of the two ortho-positions of the phenolic hydroxyl group, and is characterized in the control of steric hindrance around the phenolic hydroxyl group. It is considered that the above excellent properties are exhibited by such a structure.

[0758] From the viewpoints of improving the resolution of the photosensitive resin composition and suppressing the decrease in the sensitivity of the photosensitive resin composition, preferably, in the formula (V) of the compound represented by the general formula (V), R 51 , R 52 , R 53 and R 54 at least one of them has an aromatic ring. From the same viewpoints, the hydroxyl concentration of the hindered phenol is preferably 0.10 mol / 100 g to 0.75 mol / 100 g. Further, from the same viewpoints, preferably, in the above general formula (V), R 51 , R 52 , R 53 and R 54 at least one of them is a linear or branched alkyl group, or an aryl group sandwiching a divalent linking group, and as the preferred alkyl group, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, etc. can be mentioned, and as the preferred divalent linking group, for example, a thioether group, a substituted or unsubstituted alkylene group, etc. can be mentioned, and the aryl group may be substituted with a hydroxyl group or an alkyl group.

[0759] Further, from the same viewpoints, as the compound represented by the above general formula (V), for example, the compound represented by the following general formula (VI), the compound represented by the following general formula (VIII), the compound represented by the following general formula (IX), the compound represented by the following general formula (X) are preferred:

[0760]

[0761] {In the formula, R 55 represents the general formula (VII), and R 56 , R 57 and R 58 independently of each other represent hydrogen or the following general formula (VII):

[0762]

[0763] [In the formula, R 59 and R 60 independently of each other represent hydrogen or an optionally substituted linear alkyl group, branched alkyl group, aryl group, cyclohexyl group. ].}

[0764]

[0765] {In the formula, R 61 and R 64 each independently represent a linear or branched alkyl group, and R 62 , R 63 , R 65 and R 66 each independently represent hydrogen, or a linear or branched alkyl group, and X 1 represents a divalent linking group.},

[0766]

[0767] {In the formula, R 67 , R 70 and R 73 each independently represent a linear or branched alkyl group, and R 68 , R 69 , R 71 , R 72 , R 74 and R 75 each independently represent hydrogen, or a linear or branched alkyl group, and Y 1 represents a trivalent linking group.},

[0768]

[0769] {In the formula, R 76 , R 79 , R 82 and R 85 each independently represent a linear or branched alkyl group, and R 77 , R 78 , R 80 , R 81 , R 83 , R 84 , R 86 and R 87 each independently represent hydrogen, or a linear or branched alkyl group, and Z 1 represents a tetravalent linking group.}. Moreover, examples of X 1 in the above general formula (VIII) include a thioether group, a substituted or unsubstituted alkylene group, etc.

[0770] From the viewpoints of improving the resolution of the photosensitive resin composition and suppressing the decrease in the sensitivity of the photosensitive resin composition, the compound represented by the general formula (V) preferably has a molecular weight of about 130 to about 1000, more preferably has a molecular weight of about 200 to about 800, still more preferably has a molecular weight of about 300 to about 500, and most preferably has a molecular weight of about 300 to about 400. In addition, preferably, it has a specific gravity of about 1.02 to about 1.12 or a melting point of 155°C or higher (for example, 208°C or higher); alternatively, it is poorly soluble in water and readily soluble in organic solvents such as methanol, acetone, and toluene; or it is a solid (for example, powder, crystal, etc.) or a liquid during use.

[0771] Examples of the compound represented by the general formula (V) include 4,4'-thiobis(6-tert-butyl-m-cresol), 4,4'-butylidenebis(3-methyl-6-tert-butylphenol), styrenated phenol (manufactured by Kawaguchi Chemical Industry Co., Ltd., ANTAGESP), tribenzylphenol (manufactured by Kawaguchi Chemical Industry Co., Ltd., TBP, phenol having 1 to 3 benzyl groups), and the like. Among these, 4,4'-thiobis(6-tert-butyl-m-cresol) and 4,4'-butylidenebis(3-methyl-6-tert-butylphenol) are preferred from the viewpoints of improving the resolution and suppressing the decrease in the sensitivity of the photosensitive resin composition because of the large content of the compound represented by the general formula (I).

[0772] The proportion of the compound represented by the above general formula (V) relative to the total mass of the photosensitive resin composition is 0.001% by mass to 10% by mass. From the viewpoint of improving the resolution, this proportion is 0.001% by mass or more, preferably 0.01% by mass or more, more preferably 0.05% by mass or more, still more preferably 0.1% by mass or more, particularly preferably 0.5% by mass or more, and most preferably 0.7% by mass or more. On the other hand, from the viewpoints of less decrease in sensitivity and improvement in resolution, this proportion is 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, still more preferably 2% by mass or less, particularly preferably 1.5% by mass or less.

[0773] In the present fourth embodiment, as the hindered phenol, compounds other than the compound represented by the general formula (V) may be further contained. Examples of the compounds other than the compound represented by the general formula (V) include 2,6-di-tert-butyl-4-methylphenol, 2,5-di-tert-amylhydroquinone, 2,5-di-tert-butylhydroquinone, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), bis(2-hydroxy-3-tert-butyl-5-ethylphenyl)methane, triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], pentaerythritol tetra[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,2'-thio-diethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, N,N'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxyhydrocinnamide), diethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, tris(3,5-di-tert-butyl-4-hydroxybenzyl)-isocyanurate, and the like.

[0774] In the present fourth embodiment, with respect to the total mass of the photosensitive resin composition, the total content of all the hindered phenols in the photosensitive resin composition is preferably 0.001% by mass to 10% by mass.

[0775] In this fourth embodiment, the photosensitive resin composition may also contain stabilizers other than hindered phenols. As stabilizers other than hindered phenols, it is preferable to contain at least one selected from the group consisting of the following substances: radical polymerization inhibitors such as p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, cuprous chloride, 2,6-di-tert-butyl-p-cresol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), diphenylnitrosamine, triethylene glycol-bis(3-3-tert-butyl-5-methyl-4-hydroxyphenylpropionate), and aluminum salt of nitrosophenylhydroxylamine; benzotriazoles such as 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-tolyltriazole, 1-(2-dioctylaminomethyl)-benzotriazole, and bis(N-2-hydroxyethyl)aminomethylene-1,2,3-benzotriazole; carboxybenzotriazoles such as 4-carboxy-1,2,3-benzotriazole, 5-carboxy-1,2,3-benzotriazole, 6-carboxy-1,2,3-benzotriazole, a 1:1 mixture of 1-(2-dibutylaminomethyl)-5-carboxybenzotriazole and 1-(2-dibutylaminomethyl)-6-carboxybenzotriazole, N-(N,N-di-2-ethylhexyl)aminomethylenecarboxybenzotriazole, N-(N,N-di-2-hydroxyethyl)aminomethylenecarboxybenzotriazole, and N-(N,N-di-2-ethylhexyl)aminoethylenecarboxybenzotriazole; and epoxyalkane compounds having glycidyl groups such as neopentyl glycol diglycidyl ether (e.g., Epolight 1500NP manufactured by Kyoeisha Chemical Co., Ltd.), nonaethylene glycol diglycidyl ether (e.g., Epolight 400E manufactured by Kyoeisha Chemical Co., Ltd.), bisphenol A-propylene oxide 2 mol adduct diglycidyl ether (e.g., Epolight 3002 manufactured by Kyoeisha Chemical Co., Ltd.), hydrogenated bisphenol A diglycidyl ether (e.g., Epolight 4000 manufactured by Kyoeisha Chemical Co., Ltd.), 1,6-hexanediol diglycidyl ether (e.g., Epolight 1600 manufactured by Kyoeisha Chemical Co., Ltd.), etc.

[0776] In this fourth embodiment, the total content of all stabilizers in the photosensitive resin composition is preferably in the range of 0.001% by mass to 3% by mass, more preferably in the range of 0.01% by mass to 1% by mass, and still more preferably in the range of 0.05% by mass to 0.7% by mass. The total content of the stabilizers is preferably 0.001% by mass or more from the viewpoint of imparting good storage stability to the photosensitive resin composition, and preferably 3% by mass or less from the viewpoint of maintaining the sensitivity of the photosensitive resin layer.

[0777] [Other components]

[0778] In addition to the components (A) to (D) described above, the photosensitive resin composition of this fourth embodiment may further contain other components. Examples of such other components include leuco dyes, basic dyes, plasticizers, antioxidants, free radical polymerization inhibitors, solvents, and the like.

[0779] [Leuco dye]

[0780] The above leuco dye can be blended in the photosensitive resin composition of this fourth embodiment in order to impart appropriate color developability and excellent stripping characteristics to the resist cured film.

[0781] Specific examples of the leuco dye include, for example, leuco crystal violet (tris[4-(dimethylamino)phenyl]methane), 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide, 3-(4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)phthalide, 3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide, 1,3-dimethyl-6-diethylaminofluoran, 2-chloro-3-methyl-6-dimethylaminofluoran, 3-dibutylamino-6-methyl-7-anilinofluoran, 3-diethylamino-6-methyl-7-anilinofluoran, 3-diethylamino-6-methyl-7-xylidinofluoran, 2-(2-chloroanilino)-6-dibutylaminofluoran, 3,6-dimethoxyfluoran, 3,6-din-butoxyfluoran, 1,2-benzofluoran-6-diethylamino, 1,2-benzofluoran-6-dibutylamino, 1,2-benzofluoran-6-ethylisoamylamino, 2-methyl-6-(N-p-tolyl-N-ethylamino)fluoran, 2-(N-phenyl-N-methylamino)-6-(N-p-tolyl-N-ethylamino)fluoran, 2-(3'-trifluoromethylanilino)-6-diethylaminofluoran, 3-chloro-6-cyclohexylamino-fluoran, 2-methyl-6-cyclohexylamino-fluoran, 3-methoxy-4-dodecyloxystyrylquinoline, and the like. Among them, leuco crystal violet is preferred.

[0782] The content of the leuco dye in the photosensitive resin composition of this fourth embodiment is preferably 0.6% by mass to 1.6% by mass, more preferably 0.7% by mass to 1.2% by mass. By setting the use ratio of the leuco dye within this range, good color developability and good peelability can be achieved.

[0783] [Basic dye]

[0784] As the above basic dyes, for example, basic green 1 [CAS number (the same hereinafter): 633-03-4] (for example, Aizen Diamond Green GH, trade name, manufactured by Hodogaya Chemical Co., Ltd.), malachite green oxalate [2437-29-8] (for example, Aizen Malachite Green, trade name, manufactured by Hodogaya Chemical Co., Ltd.), brilliant green [633-03-4], magenta [632-99-5], methyl violet [603-47-4], methyl violet 2B [8004-87-3], crystal violet [548-62-9], methyl green [82-94-0], victoria blue B [2580-56-5], basic blue 7 [2390-60-5] (for example, Aizen Victoria Pure Blue BOH, trade name, manufactured by Hodogaya Chemical Co., Ltd.), rhodamine B [81-88-9], rhodamine 6G [989-38-8], basic yellow 2 [2465-27-2], diamond green, etc. Among them, one or more selected from basic green 1, malachite green oxalate, basic blue 7, and diamond green are preferred, and basic green 1 is particularly preferred from the viewpoints of hue stability and exposure contrast.

[0785] The content of the basic dye in the photosensitive resin composition of this fourth embodiment is preferably in the range of 0.001% by mass to 3% by mass, more preferably in the range of 0.01% by mass to 2% by mass, and still more preferably in the range of 0.01% by mass to 1.2% by mass. By adopting the use ratio within this range, good color development properties and high sensitivity can be achieved concurrently.

[0786] [Solvent]

[0787] The photosensitive resin composition of this fourth embodiment may be a mixture of the above components (A) to (C) and optionally used other components, or may be used in the form of a photosensitive resin composition preparation liquid formed by adding an appropriate solvent to these components.

[0788] As the solvent used herein, for example, ketone compounds such as methyl ethyl ketone (MEK); alcohols such as ethanol, ethanol, and isopropyl alcohol, etc.

[0789] As the use ratio of the solvent, a ratio that can make the viscosity of the photosensitive resin composition preparation liquid at 25°C be 500 to 4000 mPa·s is preferably adopted.

[0790] <Photosensitive element>

[0791] In this fourth embodiment, the photosensitive element is a laminate (photosensitive resin laminate) formed by laminating a photosensitive resin layer formed from the above photosensitive resin composition on a support. Optionally, a protective layer may be provided on the surface of the photosensitive resin layer opposite to the support.

[0792] [Support]

[0793] As the support, a transparent substrate that transmits light emitted from the self-exposure light source is preferred. Examples of such a support include polyethylene terephthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, polymethyl methacrylate copolymer film, polystyrene film, polyacrylonitrile film, styrene copolymer film, polyamide film, cellulose derivative film, etc. As these films, stretched films may be used as needed.

[0794] The haze of the support is preferably 5 or less.

[0795] When the thickness of the support is thin, it is advantageous in terms of image formability and economy, but the strength needs to be maintained. Considering both, a support with a thickness of 10 μm to 30 μm can be preferably used.

[0796] [Photosensitive resin layer]

[0797] When the photosensitive resin composition used in the formation of the photosensitive resin layer contains a solvent, the solvent may remain in the photosensitive resin layer, but it is preferably removed.

[0798] The thickness of the photosensitive resin layer is preferably 5 μm to 100 μm, more preferably 7 μm to 60 μm. The thinner the thickness, the higher the resolution, and the thicker the thickness, the higher the film strength. Therefore, the thickness of the composition layer can be appropriately adjusted within the above range according to the use.

[0799] [Protective layer]

[0800] An important characteristic of the protective layer is that the adhesion to the photosensitive resin layer is sufficiently less than the adhesion between the support and the photosensitive resin layer, and it can be easily peeled off. As the protective layer, for example, polyethylene film, polypropylene film, etc. can be preferably used. In addition, films with excellent peelability disclosed in, for example, Japanese Patent Application Laid-Open No. 59-202457 can be used.

[0801] The thickness of the protective layer is preferably 10 μm to 100 μm, more preferably 10 μm to 50 μm.

[0802] [Method for manufacturing a photosensitive element]

[0803] The photosensitive element can be manufactured by sequentially laminating a support, a photosensitive resin layer, and a protective layer as needed. As a lamination method for the support, the photosensitive resin layer, and the protective layer, a known method can be adopted.

[0804] For example, the photosensitive resin composition is prepared into the aforementioned photosensitive resin composition preparation liquid. First, it is coated on the support using a bar coater or a roll coater and dried to form a photosensitive resin layer formed of the photosensitive resin composition on the support. Then, as needed, a protective layer is laminated on the formed photosensitive resin layer, thereby enabling the manufacture of a photosensitive element.

[0805] <Method for forming an anti - etching pattern>

[0806] The above - mentioned photosensitive element can be used to form an anti - etching pattern on a substrate.

[0807] The method for forming an anti - etching pattern preferably sequentially includes the following processes:

[0808] A lamination process of laminating the photosensitive resin layer of the photosensitive element on a conductor substrate;

[0809] An exposure process of exposing the laminated photosensitive resin layer; and

[0810] A development process of developing the exposed photosensitive resin layer.

[0811] In the method for forming an anti - etching pattern of this fourth embodiment, first, in the lamination process, a photosensitive resin layer is formed on the substrate using a laminator. Specifically, when the photosensitive element has a protective layer, after peeling off the protective layer, the photosensitive resin layer is heat - pressed onto the substrate surface using a laminator for lamination.

[0812] As the substrate, a metal plate or an insulating substrate with a metal film is used. As the material of the metal, for example, copper, stainless steel (SUS), glass, indium tin oxide (ITO), etc. can be cited. These substrates can also have through - holes for multi - layer substrates.

[0813] Here, the photosensitive resin layer can be laminated only on one side of the substrate surface, or can be laminated on both sides of the substrate as needed. The heating temperature at this time is preferably set to 40°C to 160°C. From the viewpoint of further improving the adhesion of the obtained anti - etching pattern to the substrate, it is preferable to perform the heat - pressing 2 times or more. When performing the pressing 2 times or more, a two - stage laminator equipped with a double - roll can be used, or the laminate of the substrate and the photosensitive resin layer can be passed through the roll several times for pressing.

[0814] In addition, in the lamination process, the photosensitive resin layer of the photosensitive element can be laminated on the conductor substrate with the wetting agent layer interposed therebetween. This is a preferred lamination method from the viewpoints of improving followability and yield. As the wetting agent, it is preferable to contain one or more selected from pure water, deionized water, and electrolyzed water, and a copper chelating agent (for example, one or more compounds selected from the group consisting of imidazole compounds, triazole compounds, pyridine compounds, and pyrazole compounds).

[0815] Next, in the exposure process, the photosensitive resin layer is exposed using an exposure machine. This exposure can be performed through the support without peeling the support, or can be performed after peeling the support as needed.

[0816] By performing this exposure in a pattern, after the development process described later, a resist film (resist pattern) having a desired pattern can be obtained. The patterned exposure can be performed by either a method of exposing through a photomask or maskless exposure. When exposing through a photomask, the exposure amount is determined by the light source illuminance and the exposure time. The exposure amount can be measured using a light meter.

[0817] In maskless exposure, a photomask is not used, and exposure is performed on the substrate using a direct drawing device. As the light source, a semiconductor laser having a wavelength of 350 nm to 410 nm, an ultra-high pressure mercury lamp, etc. are used. In maskless exposure, the drawn pattern is controlled by a computer, and the exposure amount is determined by the illuminance of the exposure light source and the moving speed of the substrate.

[0818] Next, in the development process, the exposed photosensitive resin layer is developed. For example, the unexposed portion of the photosensitive resin layer is removed using a developer. After exposure, when there is a support on the photosensitive resin layer, it is preferably removed before being subjected to the development process.

[0819] In the development process, a developer formed of an alkaline aqueous solution is used to develop and remove the unexposed portion to obtain a resist image. As the alkaline aqueous solution, for example, an aqueous solution of Na 2 CO 3 、K 2 CO 3 etc. is preferably used. The alkaline aqueous solution is selected according to the characteristics of the photosensitive resin layer, and an aqueous solution of Na 2 CO 3 with a concentration of 0.2% by mass to 2% by mass is preferably used. A surfactant, an antifoaming agent, a small amount of an organic solvent for promoting development, etc. may also be mixed into the alkaline aqueous solution.

[0820] The temperature of the developer in the development process is preferably maintained at a constant temperature in the range of 20°C to 40°C.

[0821] An etching pattern is obtained through the above procedures. Optionally, a heating process at 100°C to 300°C can be further performed. Conducting this heating process is appropriate from the perspective of further improving chemical resistance. Heating can be carried out using a heating furnace with suitable methods such as hot air, infrared rays, or far-infrared rays.

[0822] <Method for forming a circuit board>

[0823] The method for forming a circuit board according to this fourth embodiment preferably includes the following procedures in sequence:

[0824] A lamination process of laminating a photosensitive resin layer of a photosensitive element on a conductor substrate;

[0825] An exposure process of exposing the laminated photosensitive resin layer;

[0826] A development process of developing the exposed photosensitive resin layer;

[0827] A conductor pattern formation process of etching or plating the conductor substrate on which an etching pattern has been formed through development; and

[0828] A stripping process of stripping the etching pattern.

[0829] In the conductor pattern formation process, on the substrate on which an etching pattern has been formed, a conductor pattern can be formed on the substrate surface (such as a copper surface) exposed through the development process using a known etching method or plating method.

[0830] In the above stripping process, the substrate on which a conductor pattern has been formed is brought into contact with an appropriate stripping solution to strip and remove the etching pattern. Through this process, a desired circuit board is obtained.

[0831] The stripping solution used in the stripping process is preferably an alkaline aqueous solution. As such an alkaline aqueous solution, for example, a 2% to 5% by mass NaOH aqueous solution or KOH aqueous solution is preferably used. In the stripping solution, a small amount of a water-soluble solvent such as alcohol can be added. The temperature of the stripping solution in the stripping process is preferably set to 40°C to 70°C.

[0832] The photosensitive resin composition, photosensitive element, method for forming an etching pattern, and method for manufacturing a circuit board according to this fourth embodiment can be extremely suitable for manufacturing, for example, printed circuit boards, lead frames, substrates with concavo-convex patterns, semiconductor packages, etc.

[0833] It should be noted that regarding the measurement methods of the above various parameters, in the absence of special instructions, they are measured according to the measurement methods in the following examples.

[0834] Examples

[0835] <Examples and comparative examples related to the first embodiment>

[0836] Hereinafter, the photosensitive resin composition of the first embodiment will be specifically described by way of examples.

[0837] (1) Measurement of raw material physical property values

[0838] <Measurement of weight average molecular weight>

[0839] Regarding the weight average molecular weight of the polymer, using gel permeation chromatography (GPC) manufactured by JASCO Corporation (pump: Gulliver, PU-1580 type, column: 4 columns in series of Shodex (registered trademark) (KF-807, KF-806M, KF-806M, KF-802.5) manufactured by Showa Denko K.K., mobile phase solvent: tetrahydrofuran, using the standard curve obtained from a polystyrene standard sample (Shodex STANDARD SM-105 manufactured by Showa Denko K.K.)), it was determined in terms of polystyrene conversion value.

[0840] <Acid equivalent>

[0841] In this specification, the acid equivalent refers to the mass (grams) of a polymer having 1 equivalent of carboxyl groups in the molecule. Using the Hiranuma automatic titrator (COM-555) manufactured by Hiranuma Sangyo Co., Ltd., the acid equivalent was measured by potentiometric titration using a 0.1 mol / L aqueous sodium hydroxide solution.

[0842] (2) Method for preparing evaluation samples and analysis

[0843] <Fabrication of photosensitive element>

[0844] Mix each of the components shown in Table 1 and the following components, and further add methyl ethyl ketone (MEK) to prepare a photosensitive resin composition with a solid content concentration of 53% by mass.

[0845] As the coloring matter, 0.04 parts by mass of Diamond Green;

[0846] As the leuco dye, 0.6 parts by mass of leuco crystal violet;

[0847] As the halogen compound, 0.7 parts by mass of tribromomethylphenyl sulfone;

[0848] As the plasticizer, 2 parts by mass of p-toluenesulfonamide;

[0849] As the benzotriazoles, 0.05 parts by mass of carboxybenzotriazole;

[0850] As the benzotriazoles, 0.15 parts by mass of 1-(2-din-octylaminomethyl)-benzotriazole;

[0851] As an antioxidant, 0.05 parts by mass of hydrogenated bisphenol A diglycidyl ether (Kyoeisha Chemical Co., Ltd., Epolight 4000); and

[0852] As a free radical polymerization inhibitor, 0.004 parts by mass of aluminum tris(nitrosophenylhydroxylamine).

[0853] The numbers in the respective component columns in Table 1 are the amounts (parts by mass) of the respective components used for preparing the composition.

[0854] The obtained photosensitive resin composition was uniformly coated on a polyethylene terephthalate film having a thickness of 16 μm (R310 manufactured by Mitsubishi Rayon Co., Ltd., haze value 2.1%) as a support using a bar coater, and then heated and dried in a dryer at a temperature of 95°C for 2.5 minutes to form a photosensitive resin composition layer having a thickness of 25 μm on the support.

[0855] Next, a polyethylene film having a thickness of 19 μm (GF-18 manufactured by Tamapoly Co., Ltd.) as a protective layer was pasted on the surface of the photosensitive resin composition layer opposite to the support to obtain a photosensitive element.

[0856] <Substrates used in the evaluation>

[0857] Separately, as a substrate for evaluating the hole covering property, a substrate having 1008 through holes with a diameter of 6 mm formed on a copper-clad laminate substrate having a thickness of 1.6 mm with a copper foil having a thickness of 35 μm laminated thereon was used;

[0858] As a substrate for evaluation other than the hole covering property, a copper-clad laminate substrate having a thickness of 0.4 mm with a copper foil having a thickness of 18 μm laminated thereon was used.

[0859] The substrate for evaluating the hole covering property was subjected to surface conditioning by surface treatment using a jet abrasive grinder and then used for evaluation.

[0860] The substrate for evaluation other than the hole covering property was subjected to surface conditioning by sequentially performing surface treatment using a soft etchant (CPE-900 manufactured by Ryoei Chemical Co., Ltd.) and surface cleaning using a 10% by mass H 2 SO 4 aqueous solution and then used for evaluation.

[0861] <Lamination>

[0862] On the surface-conditioned substrate, while peeling off the polyethylene film of the photosensitive element obtained in each example or comparative example, lamination was performed using a hot roll laminator (AL-70 manufactured by Asahi Kasei Corporation) under the conditions of a roll temperature of 105°C, an air pressure of 0.35 MPa, and a lamination speed of 1.5 m / min.

[0863] <Exposure>

[0864] Exposure is performed by a direct imaging exposure apparatus (Paragon Ultra 200, manufactured by Orbotech Ltd., main wavelength 355 nm) using a direct imaging exposure method.

[0865] Regarding the exposure pattern, it will be described later in each evaluation item.

[0866] <Development>

[0867] After peeling the support from the exposed photosensitive resin composition layer, a soda developer (developer for dry film, manufactured by FUJI KIKOU CO., LTD.) is used to spray a 1 mass% Na 2 CO 3 aqueous solution at 30 °C for twice the minimum development time to dissolve and remove the unexposed portion of the photosensitive resin composition layer. After development, it is washed with pure water for 1.5 times the development time, treated with an air knife for water removal, and then dried with warm air to obtain a substrate with a cured film for evaluation.

[0868] The above-mentioned minimum development time refers to the minimum time required until the unexposed portion of the photosensitive resin composition layer is completely dissolved and removed.

[0869] <Evaluation of Sensitivity>

[0870] In the evaluation of sensitivity, a laminated substrate 15 minutes after the above <Lamination> is used.

[0871] For this laminated substrate, after directly imaging and exposing a mask pattern of 10 lines with a line / space = 40 μm / 40 μm, development is performed by the method described in the above <Development>. The resist top width of the obtained resist pattern is measured by an optical microscope, and the sensitivity is evaluated according to the following criteria.

[0872] When the exposure dose at which the resist top width reaches 39.0 μm is 28 mJ or less: Sensitivity "○ (Good)"

[0873] When the exposure dose at which the resist top width reaches 39.0 μm exceeds 28 mJ: Sensitivity "× (Poor)"

[0874] Here, the measurement position of the resist line is set at the 5th line from the end among the 10 lines, about 5 mm from the end in the length direction, and the average value of 3 measurements is used as the measured value. At the end and center of the pattern, the line width is different due to the diffusion of the developer and cleaning water, and there is a tendency for the resist line on the end side to become thinner.

[0875] The exposure dose in the following evaluation items is the exposure dose at which the top width of the resist reaches 39.0 μm for a mask pattern with a line / space of 40 μm / 40 μm as described in the above <Evaluation of Sensitivity>.

[0876] <Evaluation of Resolution>

[0877] In the evaluation of resolution, a laminated substrate 15 minutes after the above <Lamination> is used.

[0878] For this laminated substrate, patterns with various line / space = 1 / 1 dimensions are directly drawn and exposed, and then developed by the method described in the above <Development>.

[0879] For the obtained patterns, the minimum pattern width formed is observed with an optical microscope, and the resolution is evaluated according to the following criteria.

[0880] When the minimum pattern width is 20 μm or less: Resolution "○ (Good)"

[0881] When the minimum pattern width exceeds 20 μm and is 24 μm or less: Resolution "△ (Acceptable)"

[0882] When the minimum pattern width exceeds 24 μm: Resolution "× (Poor)"

[0883] <Adhesion>

[0884] In the evaluation of adhesion, a laminated substrate 15 minutes after the above <Lamination> is used.

[0885] For this laminated substrate, patterns of various independent lines are directly drawn and exposed, and then developed by the method described in the above <Development>.

[0886] The obtained patterns are observed with an optical microscope, and the adhesion is evaluated according to the following criteria.

[0887] When the minimum pattern width formed normally is 18 μm or less: Adhesion "○ (Good)"

[0888] When the minimum pattern width formed normally exceeds 18 μm and is 22 μm or less: Adhesion "△ (Acceptable)"

[0889] When the minimum pattern width formed normally exceeds 22 μm: Adhesion "× (Poor)"

[0890] Here, the case where the line pattern is not formed normally means the case where the line pattern collapses, the case where the line pattern is meandering, or the case where the line pattern does not exist on the substrate.

[0891] <Hole Coverage>

[0892] The evaluation of the hole covering property is carried out by observing the laminated substrate after the above-mentioned <lamination> using a substrate having a through hole.

[0893] Measure the number of holes in which the photosensitive resin composition layer (hole covering film) formed on the through hole is broken, calculate the ratio with respect to all the holes (hole covering film breakage rate), and evaluate according to the following criteria.

[0894] When the hole covering film breakage rate is less than 0.1%: Hole covering property "◎(extremely good)"

[0895] When the hole covering film breakage rate is 0.1% or more and less than 2%: Hole covering property "○(good)"

[0896] When the hole covering film breakage rate is 2% or more: Hole covering property "×(bad)"

[0897] <Etching rate (width of the bottom of the wiring)>

[0898] The evaluation of the etching rate (width of the bottom of the wiring) is carried out using the laminated substrate 15 minutes after the above-mentioned <lamination>.

[0899] For the laminated substrate, a pattern with a line / space = 50 μm / 30 μm and having 10 lines is directly drawn and exposed. 15 minutes after the exposure, the support is peeled off from the photosensitive resin composition layer, and a 1 mass% Na 2 CO 3 aqueous solution at 30 °C is sprayed for a time twice the minimum development time using an alkali developing machine (manufactured by FUJI KIKOU CO., LTD., a developing machine for dry film) to dissolve and remove the unexposed portion of the photosensitive resin composition layer. After development, it is washed with pure water for a time 1.5 times the development time.

[0900] Next, the washed substrate having the line / space pattern is introduced into a copper chloride etching apparatus (manufactured by Tokyo Chemical Industry Co., Ltd., NLE-2000) without drying in such a manner that the orientation of the line / space of the substrate is orthogonal to the conveying direction (MD), and etching is carried out for 55 seconds at a linear speed of 2.0 m / minute under the conditions of a hydrochloric acid concentration of 3.2 mol / L, a copper chloride concentration of 2.0 mol / L, an etching spray pressure of 0.2 MPa, and an etching solution temperature of 50 °C.

[0901] After the above-mentioned etching, a 3.0 mass% NaOH aqueous solution is used as a stripping solution, and the cured film on the substrate is peeled off and removed at a temperature of 50 °C, and the bottom width of the wiring pattern in the MD direction of the copper wire thus obtained is measured with an optical microscope.

[0902] Here, the measurement position of the line of the wiring pattern is set to the 5th line from the end of 10 lines, at a position approximately 5 mm from the end in the length direction, and the average value of 3 measurements is used as the measured value. At the end and the center of the pattern, the influence of the developer and the cleaning water on the resist is different, so the line widths of the final wiring are different, and there is a tendency for the wiring width on the end side to become thinner.

[0903] <Aspect ratio of wiring width>

[0904] The evaluation of the aspect ratio of the wiring width uses the laminated substrate 15 minutes after the above-mentioned <Lamination>.

[0905] For the laminated substrate, an exposure pattern in which a pattern of 10 lines with a line / space of 50 μm / 30 μm is arranged in a shingle shape along the MD direction and the TD direction is directly drawn and exposed.

[0906] 15 minutes after the exposure, the support is peeled off from the photosensitive resin composition layer, and a 1% by mass Na 2 CO 3 aqueous solution at 30 °C is sprayed for twice the minimum development time using an alkali developer (manufactured by FUJIKIKOU CO., LTD., a developer for dry film) to dissolve and remove the unexposed portion of the photosensitive resin composition layer. After development, it is washed with pure water for 1.5 times the development time.

[0907] Next, the washed substrate having this line / space pattern is introduced into a copper chloride vacuum etching apparatus (manufactured by FUJI KIKOU CO., LTD., inlet width 750 mm, tank length 2.6 m) without drying, with the orientation of the line / space of the substrate set to be orthogonal (MD) to the conveying direction, and etched at a linear speed of 2.2 m / min for 71 seconds under the conditions of 14 columns in the MD direction of the etching solution piping (pipe interval approximately 18 cm), 14 nozzles in the TD direction on each pipe (slit nozzle, injection direction parallel to the TD direction, nozzle interval approximately 14 cm, distance from the substrate approximately 5 cm), no vibration, hydrochloric acid concentration 2.85 mol / L, copper chloride concentration 2.0 mol / L, etching spray pressure 0.3 MPa, vacuum pressure 0.15 MPa, and etching solution temperature 48 °C.

[0908] After the above etching, a 3.0% by mass NaOH aqueous solution is used as the stripping solution, and the cured film on the substrate is stripped off at a temperature of 50 °C to obtain two sets of copper line patterns in the MD direction and the TD direction, and their bottom widths are measured with an optical microscope.

[0909] Here, the measurement position of the line of the wiring pattern is set to the 5th line from the end of 10 lines and at a position about 5 mm from the end in the length direction, and the average value of 3 measurement values is used as the measurement value. Since the influence of the developer and the cleaning water diffusion on the resist is different at the end and the center of the pattern, the line width of the final wiring is different, and there is a tendency for the wiring width on the end side to become thinner.

[0910] In addition, the aspect ratio difference of the wiring width is calculated by the following formula and evaluated according to the following criteria.

[0911] Aspect ratio difference of wiring width (μm) = TD - MD

[0912] When the aspect ratio difference of the wiring width is 1 μm or less: Aspect ratio difference of the bottom width of the wiring "◎(extremely good)"

[0913] When the aspect ratio difference of the wiring width exceeds 1 μm and is 2 μm or less: Aspect ratio difference of the bottom width of the wiring "○(good)"

[0914] When the aspect ratio difference of the wiring width exceeds 2 μm and is 4 μm or less: Aspect ratio difference of the bottom width of the wiring "△(acceptable)"

[0915] When the aspect ratio difference of the wiring width exceeds 4 μm: Aspect ratio difference of the bottom width of the wiring "×(poor)"

[0916] Examples 1 to 23 and Comparative Examples 1 to 8

[0917] Respectively, the compositions of the photosensitive resin compositions used in the examples and comparative examples are shown in Table 1.

[0918] The details of each component name described in Table 1 are shown in Table 2. The compounding amounts of the respective components in Table 1 are all parts by mass in terms of solid components.

[0919] The evaluation results obtained using each composition are shown together in Table 1.

[0920]

[0921] Table 2. Component details (Sheet 1 of 2)

[0922]

[0923]

[0924] (Table 2 continued) Table 2. Component details Sheet 2 of 2

[0925]

[0926] <Examples and Comparative Examples Related to the Second Embodiment>

[0927] Hereinafter, the photosensitive resin composition of the second embodiment will be specifically described by way of examples.

[0928] (1) Measurement of raw material physical property values

[0929] <Acid equivalent>

[0930] The acid equivalent refers to the mass of a base-soluble polymer having 1 equivalent of carboxyl groups therein. The acid equivalent is measured using an automatic titrator (for example, the Hiranuma Automatic Titrator (COM-555) manufactured by Hiranuma Sangyo Co., Ltd.) by potentiometric titration using a 0.1 mol / L aqueous sodium hydroxide solution.

[0931] <Measurement of weight-average molecular weight>

[0932] Regarding the weight-average molecular weight of the polymer, gel permeation chromatography (GPC) (pump: Gulliver, model PU-1580, column: four Shodex (registered trademark) (KF-807, KF-806M, KF-806M, KF-802.5) columns manufactured by Showa Denko K.K. connected in series, mobile phase solvent: tetrahydrofuran, using a standard curve obtained from a polystyrene standard sample (Shodex STANDARD SM-105 manufactured by Showa Denko K.K.)) manufactured by JASCO Corporation is used to obtain the value in terms of polystyrene conversion.

[0933] (2) Method for preparing samples for evaluation

[0934] <Production of photosensitive element>

[0935] Each component shown in Table 3 is mixed, and methyl ethyl ketone (MEK) is further added to prepare a photosensitive resin composition having a solid content concentration of 55% by mass.

[0936] The obtained photosensitive resin composition is uniformly coated on a polyethylene terephthalate film (GR-16, manufactured by Teijin DuPont Films Japan Limited) with a thickness of 16 μm as a support using a bar coater, and then heated and dried in a dryer adjusted to 95 °C for 4 minutes to form a photosensitive resin layer with a thickness of 33 μm on the support.

[0937] Next, a polyethylene film with a thickness of 19 μm (GF-18, manufactured by Tamapoly Co., Ltd.) as a protective layer is pasted on the surface of the above photosensitive resin layer opposite to the support to obtain a photosensitive element.

[0938] <Substrate used in evaluation>

[0939] As a substrate for evaluation, a substrate obtained by surface conditioning the surface of a 1.6 mm-thick copper-clad laminate with a 35-μm rolled copper foil laminated thereon by grinding using a wet polishing roll was used. The grinding was performed twice using Scotch (registered trademark) HD#600 manufactured by 3M Corporation.

[0940] <Lamination>

[0941] On the substrate that had been surface-conditioned and preheated to 60°C, while peeling off the polyethylene film of the photosensitive element obtained in each example or comparative example, lamination was performed using a hot roll laminator (manufactured by Asahi Kasei Corporation, AL-70) under the conditions of a roll temperature of 105°C, an air pressure of 0.35 MPa, and a lamination speed of 1.5 m / min.

[0942] <Exposure>

[0943] Using a direct drawing exposure machine (manufactured by Hitachi Via Mechanics Co., Ltd., DE-1DH, light source: GaN blue-violet diode, main wavelength 405 ± 5 nm), using a Stouffer 41-step exposure meter or a mask pattern for specified DI exposure, at an illuminance of 80 mW / cm 2 exposure was performed under the condition of an exposure amount equivalent to 14 steps in the Stouffer 41-step exposure meter.

[0944] <Development>

[0945] After peeling off the support from the exposed photosensitive resin layer, using an alkali developer (manufactured by FUJI KIKOU CO., LTD., a developer for dry film), a 1 mass% Na 2 CO 3 aqueous solution at 30°C was sprayed for twice the minimum development time to dissolve and remove the unexposed portion of the photosensitive resin layer. After development, it was washed with pure water for 1.5 times the development time, subjected to water removal treatment using an air knife, and then dried with warm air to obtain a substrate with a cured film for evaluation.

[0946] The minimum development time refers to the minimum time required until the unexposed portion of the photosensitive resin layer is completely dissolved and removed.

[0947] <Etching>

[0948] For the evaluation substrate on which an etching pattern was formed by development, using a copper chloride etching device (manufactured by Tokyo Chemical Industry Co., Ltd., a copper chloride etching device), a copper chloride etching solution at 50°C (copper chloride concentration 250 g / L, HCl concentration 3 mol / L) was sprayed for 60 seconds to dissolve and remove the copper foil on the copper-clad laminate that was not covered by the etching pattern.

[0949] <Peeling>

[0950] The evaluation substrate after etching was sprayed with a 3 mass % sodium hydroxide aqueous solution heated to 50° C. to peel off the cured resist.

[0951] (3) Evaluation method

[0952] (i) Visualization Aggregation Test

[0953] The photopolymerizable resin laminate has a thickness of 50 μm and an area of ​​0.6 m 2 The photosensitive layer (resist layer) was dissolved in 200 ml of 1 mass % Na 2 CO 3 The aqueous solution is sprayed for 3 hours using a circulating spray device at a spray pressure of 0.1 MPa. Then, the developer is left for 1 day to observe the generation of aggregates. When a large amount of aggregates are generated, powdery or oily substances are observed at the bottom and sides of the spray device. In addition, aggregates sometimes float in the developer. The developer composition with good aggregation properties will not generate such aggregates at all, or even if generated, it is extremely small and can be easily washed off by water. The generation state of aggregates is visually observed and classified as follows.

[0954] ◎ (remarkably good): Aggregates are not generated at all.

[0955] ○ (good): There were no aggregates on the bottom or side of the spray device, and a very small amount of aggregates floating in the developer was observed to be visually confirmed, but was easily washed away by water washing.

[0956] △ (OK): Aggregates were floating on the bottom or part of the side of the spray device and in the developer. Even with water washing, all the aggregates could not be washed away.

[0957] × (bad): Aggregates were observed in the entire spray device and were floating in the developer. Even with water washing, all the aggregates could not be washed away, and most of them remained.

[0958] (ii) Sensitivity test

[0959] The photosensitive elements obtained in the examples and comparative examples were laminated and exposed by the above method. The exposure amount (mJ / cm2) equivalent to 14 levels in the Stouffer 41-level step exposure table was investigated based on the exposure amount and the number of levels remaining after development. 2 , 14 / 41ST exposure), and evaluated according to the following criteria.

[0960] Sensitivity "0" (good): 14 / 41ST exposure 25mJ / cm 2 The following situations

[0961] Sensitivity “×” (defective): When the 14 / 41ST exposure dose exceeds 25 mJ / cm 2 in the case of

[0962] (iii) Resolution test

[0963] After laminating using the photosensitive elements obtained in each of the examples and comparative examples according to the above method, after 15 minutes, using the specimens thus obtained, set the line / space to 1 / 1, and then perform direct drawing exposure according to the above method. Then, perform development according to the above method.

[0964] Furthermore, investigate the minimum mask line width where the cured resist lines are normally formed, and evaluate according to the following criteria.

[0965] Resolution “〇” (good): When the minimum line width is less than 25 μm

[0966] Resolution “△” (acceptable): When the minimum line width is 25 μm or more and less than 30 μm

[0967] Resolution “×” (defective): When the minimum line width is 30 μm or more

[0968] (iv) Adhesion test

[0969] After laminating using the photosensitive elements obtained in each of the examples and comparative examples according to the above method, after 15 minutes, using the specimens thus obtained, perform direct drawing exposure according to the above method. Then, perform development according to the above method.

[0970] Furthermore, when the line / space = X / 200, as X, investigate the minimum mask line width that is normally formed, and evaluate according to the following criteria.

[0971] Adhesion “〇” (good): When the minimum line width is less than 25 μm

[0972] Adhesion “△” (acceptable): When the minimum line width is 25 μm or more and less than 30 μm

[0973] Adhesion “×” (defective): When the minimum line width is 30 μm or more

[0974] Examples 1 to 6 and Comparative Examples 1 to 5

[0975] The compositions of the photosensitive resin compositions used in the examples and comparative examples are shown in Table 3, and the details of each component name in Table 3 are shown in Table 4. The compounding amounts of each component in Table 4 are all parts by mass in terms of solid components.

[0976] The evaluation results using each composition are also shown in Table 4.

[0977]

[0978] Table 4. Details of Ingredients

[0979]

[0980] <Examples and Comparative Examples of the Third Embodiment>

[0981] Hereinafter, the photosensitive resin composition of the third embodiment will be specifically described by way of examples.

[0982] The measurement of the physical property values of the polymer and the monomer, and the method for producing the evaluation samples of the examples and comparative examples will be described. Then, the evaluation method and the evaluation results for the obtained samples will be shown.

[0983] (1) Measurement or calculation of physical property values

[0984] <Measurement of the weight average molecular weight or number average molecular weight of the polymer>

[0985] Regarding the weight average molecular weight or number average molecular weight of the polymer, it was determined in terms of polystyrene conversion value using gel permeation chromatography (GPC) manufactured by JASCO Corporation (pump: Gulliver, PU-1580 type, column: 4 columns in series of Shodex (registered trademark) (KF-807, KF-806M, KF-806M, KF-802.5) manufactured by Showa Denko K.K., mobile phase solvent: tetrahydrofuran, using a standard curve obtained from a polystyrene standard sample (Shodex STANDARD SM-105 manufactured by Showa Denko K.K.)).

[0986] Furthermore, the dispersity of the polymer was calculated as the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight).

[0987] <Acid equivalent>

[0988] In this specification, the acid equivalent refers to the mass (grams) of a polymer having 1 equivalent of carboxyl groups in the molecule. The acid equivalent was measured by potentiometric titration using a Hiranuma Automatic Titrator (COM-555) manufactured by Hiranuma Sangyo Co., Ltd. and a 0.1 mol / L aqueous sodium hydroxide solution.

[0989] (2) Method for producing evaluation samples

[0990] The evaluation samples of Examples 1 to 12 and Comparative Examples 1 to 5 were produced as follows.

[0991] <Production of the photosensitive resin laminate>

[0992] The components shown in Table 5 or 6 below (where the numbers of the respective components represent the compounding amounts (parts by mass) as solid components) and a solvent are sufficiently stirred and mixed to obtain a photosensitive resin composition preparation liquid. The names of the components represented by abbreviations in Tables 5 and 6 are shown in Table 7 below. A 16-μm-thick polyethylene terephthalate film (manufactured by Mitsubishi Rayon Co., Ltd., R310-16B) is used as the support film, and the preparation liquid is uniformly coated on its surface using a bar coater, and dried in a dryer at 95°C for 3 minutes to form a photosensitive resin composition layer. The dry thickness of the photosensitive resin composition layer is 30 μm.

[0993] Next, a 19-μm-thick polyethylene film (GF-818 manufactured by Tamapoly Co., Ltd.) is pasted on the surface of the side of the photosensitive resin composition layer where the polyethylene terephthalate film is not laminated, to obtain a photosensitive resin laminate.

[0994] <Substrate surface finishing>

[0995] Using an abrasive (manufactured by Japan Carlit Co., Ltd., Sakurandom R (registered trademark #220)), a copper-clad laminate with a 35-μm-thick rolled copper foil laminated on a 0.4-mm-thick copper-clad laminate is subjected to spray abrasive grinding at a spray pressure of 0.2 MPa to produce a substrate for evaluation.

[0996] <Lamination>

[0997] While peeling off the polyethylene film of the photosensitive resin laminate, the photosensitive resin laminate is laminated on the copper-clad laminate that has been surface-adjusted and preheated to 60°C using a hot roll laminator (manufactured by Asahi Kasei Corporation, AL-700) at a roll temperature of 105°C to obtain a test piece. The air pressure is set to 0.35 MPa, and the lamination speed is set to 1.5 m / minute.

[0998] <Exposure>

[0999] Exposure is performed with a direct drawing type exposure device (manufactured by Via Mechanics Co., Ltd., DE-1DH, main wavelength 405 nm) at an exposure amount of 15 mJ / cm 2 2.

[1000] <Development>

[1001] After peeling off the polyethylene terephthalate film from the photosensitive resin laminate, using a developing device manufactured by FUJI KIKOU CO., LTD., a 1% by mass Na 2 2 CO 3An aqueous solution is sprayed for a specified time for development to dissolve and remove the unexposed portion of the photosensitive resin layer. At this time, the minimum time required for the complete dissolution of the unexposed portion of the photosensitive resin layer is measured as the minimum development time, and development is carried out for a time twice the minimum development time to produce an etching pattern. At this time, the water washing process is carried out for the same time as the development process using a flat nozzle at a water washing spray pressure of 0.15 MPa.

[1002] (3) Evaluation method of samples

[1003] <Hole covering property>

[1004] For a 0.6-mm-thick double-sided copper-clad laminate having through holes with a width of 2.0 mm × a length of 15 mm, surface treatment is carried out using a jet scrubbing type grinder. Lamination is carried out on both sides by the method described in the above <Lamination>, and the entire surface on both sides is exposed using a direct drawing type exposure apparatus (manufactured by Via Mechanics Co., Ltd., DE-1DH, main wavelength 405 nm). When development is carried out by the method described in the above <Development>, the number of broken hole covers is measured, the breakage rate with respect to all the hole covers is calculated, and grading is carried out according to the following criteria.

[1005] ◎◎(Best): The film breakage rate after development is 2% or less.

[1006] ◎(Very good): The film breakage rate after development exceeds 2% and is 4% or less.

[1007] ○(Good): The film breakage rate after development exceeds 4% and is 10% or less.

[1008] ×(Poor): The film breakage rate after development exceeds 10%.

[1009] <Contact angle (water residue short circuit failure suppression property)>

[1010] In the evaluation of the contact angle (water residue short circuit failure suppression property), after lamination by the method described in the above <Lamination>, overall surface development is carried out by the method described in the above <Exposure>, and then development is carried out by the method described in the above <Development>.

[1011] After development, the sample is subjected to contact angle measurement within 30 minutes.

[1012] The contact angle was measured by the sessile drop method based on JIS R3257. After dropping 0.5 μL of pure water onto the cured film in an environment of 23 °C and 50% RH, the contact angle was measured using an optical microscope type contact angle meter "LSE-B100" manufactured by Nic Co., Ltd. The value after 120 seconds was adopted and classified according to the following criteria. When the contact angle value is large, it indicates that the cured resist has high hydrophobicity and can suppress water residue short circuit failures.

[1013] ◎(Excellent): The contact angle is 35° or more.

[1014] ○(Good): The contact angle is 30° or more and less than 35°.

[1015] △(Permissible): The contact angle is 25° or more and less than 30°.

[1016] ×(Poor): The contact angle is less than 25°.

[1017] (4) Evaluation results

[1018] The evaluation results of Examples 1 to 12 are shown in Table 5 below, and the evaluation results of Comparative Examples 1 to 5 are shown in Table 6 below.

[1019]

[1020]

[1021] Table 7

[1022]

[1023] <Examples and Comparative Examples of the Fourth Embodiment>

[1024] Hereinafter, the photosensitive resin composition of this fourth embodiment will be specifically described by way of examples.

[1025] (1) Measurement of raw material physical property values

[1026] <Measurement of weight average molecular weight>

[1027] Regarding the weight average molecular weight of the polymer, gel permeation chromatography (GPC) (pump: Gulliver, PU-1580 type, column: 4 columns in series of Shodex (registered trademark) (KF-807, KF-806M, KF-806M, KF-802.5) manufactured by Showa Denko K.K., mobile phase solvent: tetrahydrofuran, using the standard curve obtained from a polystyrene standard sample (Shodex STANDARD SM-105 manufactured by Showa Denko K.K.)) manufactured by JASCO Corporation was used to obtain the value in terms of polystyrene conversion.

[1028] <Acid equivalent>

[1029] In this specification, the acid equivalent refers to the mass (grams) of a polymer having 1 equivalent of carboxyl groups in the molecule. The acid equivalent is measured by potentiometric titration using a Hiranuma Sangyo Co., Ltd. automatic titrator (COM-555) with a 0.1 mol / L aqueous sodium hydroxide solution.

[1030] (2) Method for preparing and analyzing samples for evaluation

[1031] <Fabrication of photosensitive element>

[1032] Mix the components shown in Table 8, and further add methyl ethyl ketone (MEK) to prepare a photosensitive resin composition with a solid component concentration of 56% by mass. The numbers in the component columns in Table 8 are the amounts (parts by mass) of the respective components used for preparing the composition.

[1033] The obtained photosensitive resin composition was uniformly coated on a 16-μm-thick polyethylene terephthalate film (GR-16, haze value 2.7%, manufactured by Teijin DuPont Films Japan Limited) as a support using a bar coater, and then heat-dried in a dryer adjusted to 95°C for 3 minutes and 20 seconds to form a 33-μm-thick photosensitive resin layer on the support.

[1034] Next, a 19-μm-thick polyethylene film (GF-18, manufactured by Tamapoly Co., Ltd.) as a protective layer was pasted on the surface of the photosensitive resin layer opposite to the support to obtain a photosensitive element.

[1035] <Substrate used in evaluation>

[1036] As the evaluation substrate, a substrate obtained by surface conditioning the surface of a 1.6-mm-thick copper-clad laminate with a 35-μm rolled copper foil laminated thereon by wet polishing with a polishing roll was used. The polishing was performed twice using Scotch (registered trademark) HD#600 manufactured by 3M Company.

[1037] <Lamination>

[1038] On the surface-conditioned substrate, while peeling off the polyethylene film of the photosensitive element obtained in each example or comparative example, lamination was performed using a hot roll laminator (AL-70, manufactured by Asahi Kasei Corporation) under the conditions of a roll temperature of 105°C, an air pressure of 0.35 MPa, and a lamination speed of 1.5 m / min.

[1039] <Exposure>

[1040] Using a direct drawing exposure machine (manufactured by Hitachi Via Mechanics Co., Ltd., model DE-1AH, light source: GaN blue-violet diode, main wavelength 405 ± 5 nm), and using a mask pattern for specified DI exposure, exposure is performed under the condition of an illuminance of 15 mW / cm 2 .

[1041] Regarding the exposure pattern and exposure amount, they will be described later in the items of each evaluation item.

[1042] <Development>

[1043] After peeling off the support from the exposed photosensitive resin layer, a 0.8 mass% Na 2 CO 3 aqueous solution at 29 °C is sprayed for a time twice the minimum development time using an alkali developer (manufactured by FUJI KIKOU CO., LTD., a developer for dry film) to dissolve and remove the unexposed portion of the photosensitive resin layer. After development, it is washed with pure water for the same time as the development time, and after water washing, it is not subjected to warm air drying treatment, but the substrate is allowed to dry naturally, thereby obtaining a substrate with a cured film for evaluation.

[1044] The above minimum development time refers to the minimum time required until the unexposed portion of the photosensitive resin layer is completely dissolved and removed, and it varies depending on the concentration or temperature of the developer, the spraying direction or spraying amount, pressure, vibration frequency, etc.

[1045] Here, the minimum development time is classified as follows:

[1046] ○: The minimum development time exceeds 30 seconds.

[1047] ×: The minimum development time is 30 seconds or less.

[1048] <Evaluation of sensitivity>

[1049] In the evaluation of sensitivity, a laminated substrate 15 minutes after the above <Lamination> is used.

[1050] For this laminated substrate, after directly drawing and exposing a mask pattern of 10 lines with a line / space = 40 μm / 40 μm, development is performed using the method described in the above <Development>. The resist top width of the obtained resist pattern is measured with an optical microscope, and the exposure amount at which the resist top width reaches 39 μm is used as the evaluation of sensitivity.

[1051] Here, the measurement position of the resist line is set to the 5th line from the end among 10 lines, at a position approximately 5 mm from the end in the length direction, and the average value of 3 measurements is used as the measured value. At the end and the center of the pattern, the line width is different due to the influence of the diffusion of the developer and the cleaning water, and there is a tendency for the resist line on the end side to become thinner. Therefore, it is important to limit the measurement position.

[1052] The exposure amount in the following evaluation items is the exposure amount that makes the top width of the resist reach 39 μm for a mask pattern with a line / space = 40 μm / 40 μm as described in the above <Evaluation of Sensitivity>. Here, the sensitivity is classified according to the exposure amount as follows:

[1053] ○: The exposure amount to reach a line width of 39 μm is 28 mJ / cm 2 or less.

[1054] ×: The exposure amount to reach a line width of 39 μm exceeds 28 mJ / cm 2 .

[1055] <Evaluation of Resolution>

[1056] In the evaluation of resolution, a laminated substrate 15 minutes after the above <Lamination> is used.

[1057] For this laminated substrate, after directly drawing and exposing patterns with various sizes of line / space = 1 / 1, development is performed by the method described in the above <Development>.

[1058] For the obtained pattern, the minimum pattern width formed is observed with an optical microscope, and the resolution is evaluated according to the following criteria.

[1059] ○: The minimum pattern width formed is 28 μm or less.

[1060] ×: The minimum pattern width formed exceeds 28 μm.

[1061] <Evaluation of Adhesion>

[1062] In the evaluation of adhesion, a laminated substrate 15 minutes after the above <Lamination> is used.

[1063] For this laminated substrate, after directly drawing and exposing patterns of various sizes of independent lines, development is performed by the method described in the above <Development>.

[1064] The obtained pattern is observed with an optical microscope, and the adhesion is evaluated according to the following criteria.

[1065] Here, the case where the line pattern is not formed properly means the case where the line pattern collapses, the case where the line pattern is meandering, or the case where the line pattern does not exist on the substrate.

[1066] ○: The minimum pattern width formed is 28 μm or less.

[1067] ×: The minimum pattern width formed exceeds 28 μm.

[1068] <Evaluation of aggregability>

[1069] Dissolve the photosensitive layer (resist layer) with a thickness of 50 μm and an area of 0.6 m 2 in 200 ml of 1 mass% Na 2 CO 3 aqueous solution, and spray it for 3 hours at a spray pressure of 0.1 MPa using a circulating spray device. Then, let the developer stand for 1 day and observe the generation of aggregates. When a large amount of aggregates are generated, powdery substances or oily substances are observed at the bottom and side of the spray device. In a composition with good aggregability of the developer, no such aggregates are generated at all. Based on the generation state of the aggregates, the aggregability is classified as follows:

[1070] ○: No aggregates are generated at all.

[1071] △: Aggregates are observed in a part of the bottom or side of the spray device.

[1072] ×: Aggregates are observed in the whole spray device.

[1073] <Evaluation of peelability>

[1074] Use the substrate after 15 minutes of the treatment described in the above <Lamination>. For this laminated substrate, directly draw and expose a 4 cm × 6 cm rectangular pattern, and then develop it by the method described in the above <Development>.

[1075] Immerse the cured resist on the obtained substrate in 50°C, 3 mass% NaOH, and measure the time until the resist is completely peeled off from the substrate as the peeling time.

[1076] Here, the peelability is classified as follows:

[1077] ○: The time until complete peeling is 40 seconds or less.

[1078] ×: The time until complete peeling exceeds 40 seconds.

[1079] Examples 1 to 7 and Comparative Examples 1 to 4

[1080] Respectively, the compositions of the photosensitive resin compositions used in the examples and comparative examples are shown in Table 8, and the details of each component name described in Table 8 are shown in Table 9. The compounding amounts of each component in Table 8 are all parts by mass in terms of solid components.

[1081] The evaluation results using each composition are also shown in Table 8.

[1082]

[1083] Table 9

[1084]

Claims

1. A photosensitive resin composition, characterized in that, it contains: (A) An alkali-soluble polymer; (B) An ethylenically unsaturated bond-containing compound; and (C) A photopolymerization initiator; The (A) alkali-soluble polymer contains 10% by mass to 24% by mass of structural units of (meth)acrylic acid and 35% by mass to 90% by mass of structural units of styrene based on the total mass of the monomers constituting the (A) alkali-soluble polymer, and, the (B) ethylenically unsaturated bond-containing compound has a weight-average molecular weight of 1200 to 5000.

2. The photosensitive resin composition according to claim 1, wherein, the weight-average molecular weight of the (B) ethylenically unsaturated bond-containing compound is 1300 or more.

3. The photosensitive resin composition according to claim 1 or 2, wherein, 40% by mass or more of the (B) ethylenically unsaturated bond-containing compound is an alkylene oxide-modified bisphenol A di(meth)acrylate compound represented by the following general formula (II), In formula (II), R 3 and R 4 each independently represent a hydrogen atom or a methyl group, A is C 2 H 4 , B is C 3 H 6 , n 1 , n 2 , n 3 and n 4 are integers satisfying the relationship of n 1 + n 2 + n 3 + n 4 = 2 to 50. The arrangement of the repeating units of -(A-O)- and -(B-O)- can be random or block. In the case of block, either -(A-O)- or -(B-O)- is optionally on the biphenyl side.

4. The photosensitive resin composition according to claim 3, wherein, n in the general formula (II) 1 , n 2 , n 3 and n 4 satisfy the relationship of n 1 +n 2 +n 3 +n 4 = 30 to 50 5. The photosensitive resin composition according to claim 3, wherein, n in the general formula (II) 1 n 2 n 3 and n 4 satisfy the relationship of n 1 + n 2 + n 3 + n 4 = 2 to 10 6. The photosensitive resin composition according to claim 1 or 2, wherein, the (B) ethylenically unsaturated bond-containing compound contains a tri(meth)acrylate compound represented by the following general formula (III), In formula (III), R 5 , R 6 and R 7 each independently represent a hydrogen atom or a methyl group, X represents an alkylene group having 2 to 6 carbon atoms, m 2 , m 3 and m 4 each independently are integers from 0 to 40, m 2 + m 3 + m 4 is from 1 to 40, and when m 2 + m 3 + m 4 is 2 or more, the plurality of Xs may be the same or different from each other optionally.

7. The photosensitive resin composition according to claim 1 or 2, wherein, the (B) ethylenically unsaturated bond-containing compound contains a urethane di(meth)acrylate compound represented by the following general formula (IV), In formula (IV), R 8 and R 9 each independently represents a hydrogen atom or a methyl group, Y represents an alkylene group having 2 to 6 carbon atoms, Z represents a divalent organic group, s and t are each independently an integer from 0 to 40, and s + t ≥ 1.

8. The photosensitive resin composition according to any one of claims 1 to 7, wherein, the (A) alkali-soluble polymer further contains a structural unit of butyl (meth)acrylate.

9. The photosensitive resin composition according to any one of claims 1 to 8, which is used for direct imaging exposure.

10. A method for forming a resist pattern, which comprises: a lamination step of laminating a photosensitive resin layer formed from the photosensitive resin composition according to any one of claims 1 to 9 on a support; an exposure step of exposing the photosensitive resin layer; and a development step of developing the exposed photosensitive resin layer.

11. A method for manufacturing a circuit board, which comprises: a lamination step of laminating a photosensitive resin layer formed from the photosensitive resin composition according to any one of claims 1 to 9 on a substrate; an exposure step of exposing the photosensitive resin layer; a development step of developing the exposed photosensitive resin layer to obtain a substrate having a resist pattern formed thereon; a conductor pattern forming step of etching or plating the substrate having the resist pattern formed thereon; and a stripping step of stripping the resist pattern.

12. A photosensitive resin composition, characterized in that, it contains the following components (A) to (C), (A) component: an alkali-soluble polymer having an acid equivalent of 100 to 600, (B) component: a compound having an ethylenic double bond, and (C) component: a photopolymerization initiator The (A) component contains a copolymer containing 50% by mass to 80% by mass of styrene units, The component (B) contains a compound represented by the following general formula (I). In formula (I), each R is independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and n1, n2, and n3 are independently integers from 0 to 30, where the condition n1 + n2 + n3 ≥ 6 is satisfied. The content of the compound represented by the general formula (I) is 5% by mass to 30% by mass based on the solid content of the photosensitive resin composition, and the component (C) contains an acridine compound.

13. The photosensitive resin composition according to claim 12, wherein, n1, n2, and n3 in the general formula (I) satisfy 20 ≥ n1 + n2 + n3 > 9.

14. The photosensitive resin composition according to claim 12 or 13, wherein, All Rs in the general formula (I) are hydrogen atoms.

15. The photosensitive resin composition according to any one of claims 12 to 14, wherein, The component (B) further contains a pentaerythritol-modified monomer.

16. A photosensitive element obtained by laminating a photosensitive resin layer formed from the photosensitive resin composition according to any one of claims 12 to 15 on a support.

17. A method for forming a resist pattern, characterized in that it includes: a lamination step of laminating the photosensitive resin layer of the photosensitive element according to claim 16 on a conductor substrate, an exposure step of exposing the laminated photosensitive resin layer, and a development step of removing the unexposed portion after the exposure with a developer.

18. A method for manufacturing a circuit board, characterized in that it includes: a lamination step of laminating the photosensitive resin layer of the photosensitive element according to claim 16 on a conductor substrate, an exposure step of exposing the laminated photosensitive resin layer, a development step of removing the unexposed portion after the exposure with a developer, a conductor pattern forming step of etching or plating the conductor substrate having a resist pattern formed by the development, and a stripping step of stripping the resist pattern. ​ ​

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