Photosensitive resin laminate, photosensitive element, and pattern formation method

Abstract

The present disclosure provides a photosensitive resin laminate comprising a temporary support and a photosensitive resin layer which is provided on the temporary support, wherein: the average thickness of the photosensitive resin layer is not more than 16 μm; the photosensitive resin layer contains a photosensitive resin composition which contains a binder polymer (A), a photopolymerizable compound (B) having an ethylenically unsaturated bond, and a photopolymerization initiator (C); the binder polymer (A) contains a copolymer having a weight-average molecular weight of not more than 30,000; the content of the photopolymerization initiator (C) is not less than 5.0 parts by mass with respect to 100 parts by mass of the total content of the binder polymer (A) and the photopolymerizable compound (B); and the absorbance of a photosensitive resin composition layer with respect to light having a wavelength of 365 nm or light having a wavelength of 402 nm is more than 0.005 but not more than 0.040 per 1 μm of the thickness of the photosensitive resin composition layer.

Description

Photosensitive resin laminate, photosensitive element, and pattern forming method

[0001] This disclosure relates to a photosensitive resin laminate, a photosensitive element, and a pattern forming method.

[0002] Fine wiring (conductor patterns) in electronic devices are manufactured, for example, using a photolithography process. A photolithography process includes, for example, the following steps: forming a resist pattern by laminating a photosensitive resin layer in a photosensitive resin laminate onto a substrate, and then exposing and developing it; forming a conductor pattern by etching or plating the substrate on which the resist pattern has been formed; and removing the resist pattern from the substrate.

[0003] Generally, photosensitive resin layers include a photosensitive resin composition, and both negative and positive types are known. In the case of the negative type, a resist pattern is formed by the exposed areas of the photosensitive resin layer by removing the unexposed areas through development.

[0004] The photosensitive resin layer can be provided as a photosensitive resin laminate laminated on a temporary support, or as a photosensitive film, and the composition of the photosensitive resin composition, the thickness of the photosensitive film, the cross-sectional shape or scratch resistance in the developing solution, and the line / space ratio or number of defects of the resist pattern have been investigated (see, for example, Patent Documents 1 to 4).

[0005] International Publication No. 2022 / 190208, International Publication No. 2022 / 191125, Japanese Patent Publication No. 2006-220860, International Publication No. 2023 / 127755

[0006] J. Brandrup and Edmund H. Immergut (eds.), "Polymer Handbook," (USA), 3rd edition, Wiley-Interscience, October 20, 1989, p. 209.

[0007] In recent years, due to the miniaturization and high density of electronic devices, further improvement in image quality is required for resist patterns. In particular, for manufacturing organic interposers, the demand for forming patterns with fine line widths and / or space widths (for example, 2 μm or less) is increasing. When the photosensitive resin layer is thin, it is strongly required to achieve good adhesion to the substrate and good resolution. However, in the prior art, there was room for improvement in achieving both high adhesion and high resolution in forming patterns with fine line widths and / or space widths.

[0008] Therefore, an object of the present disclosure is to provide a photosensitive resin laminate and a photosensitive element capable of achieving both high adhesion and high resolution, and a method for forming a resist pattern and a method for manufacturing a conductor pattern using the photosensitive element.

[0009] One aspect of the present disclosure is listed below: [1] A photosensitive resin laminate having a temporary support and a photosensitive resin layer on the temporary support, wherein the average thickness of the photosensitive resin layer is 16 μm or less, the photosensitive resin layer comprises a photosensitive resin composition containing (A) a binder polymer, (B) a photopolymerizable compound having an ethylenically unsaturated bond, and (C) a photopolymerization initiator, the (A) binder polymer comprises a copolymer having a weight-average molecular weight of 30,000 or less, the content of the (C) photopolymerization initiator is 5.0 parts by mass or more per 100 parts by mass of the total amount of the (A) binder polymer and the (B) photopolymerizable compound, and the absorbance for light at wavelengths of 365 nm and 402 nm per 1 μm of thickness of the photosensitive resin layer is greater than 0.005 and 0.040 or less. [2] The photosensitive resin laminate according to item 1, wherein the absorbance for light at a wavelength of 365 nm and 402 nm per 1 μm thickness of the photosensitive resin layer is greater than 0.010. [3] The photosensitive resin laminate according to item 1 or 2, wherein the absorbance for light at a wavelength of 365 nm and 402 nm per 1 μm thickness of the photosensitive resin layer is 0.025 or less. [4] The photosensitive resin laminate according to any one of items 1 to 3, wherein the (C) photopolymerization initiator comprises a dimer of 2,4,5-triarylimidazole, and the content of the 2,4,5-triarylimidazole dimer is 5.0 parts by mass or more per 100 parts by mass of the total amount of the (A) binder polymer and the (B) photopolymerizable compound. [5] The photosensitive resin laminate according to any one of items 1 to 4, wherein the binder polymer (A) contains 30% by mass or more of a copolymer having a weight-average molecular weight of 30,000 or less. [6] The photosensitive resin laminate according to any one of items 1 to 5, wherein the binder polymer (A) contains 50% by mass or more of a copolymer having a weight-average molecular weight of 30,000 or less. [7] The photosensitive resin laminate according to any one of items 1 to 6, wherein the binder polymer (A) contains a copolymer having a monomer having an aromatic ring as a copolymer component, and the content of the monomer having an aromatic ring is 35% by mass or more based on the total mass of all monomer components of component (A).[8] The photosensitive resin laminate according to any one of items 1 to 7, wherein the (A) binder polymer comprises a copolymer having styrene as a copolymer component, and the styrene content is 35% by mass or more based on the total mass of all monomer components of component (A). [9] The photosensitive resin laminate according to any one of items 1 to 8, wherein the (A) binder polymer comprises a copolymer having a weight-average molecular weight of 25,000 or less.

[10] The photosensitive resin laminate according to any one of items 1 to 9, wherein the copolymer having a weight-average molecular weight of 30,000 or less has a value of 2.2 or more and 3.6 or less obtained by the following formula: (acid value (mgKOH / g) + hydroxyl value (mgKOH / g)) / ((parts by mass of constituent units derived from monomers having aromatic rings per 100 parts by mass of copolymer having a weight-average molecular weight of 30,000 or less)).

[11] The photosensitive resin laminate according to any one of items 1 to 10, wherein the (A) binder polymer includes a copolymer having constituent units derived from alkyl (meth)acrylate in which the hydrogen atoms of the alkyl group are substituted with hydroxyl groups.

[12] The copolymer having a weight-average molecular weight of 30,000 or less has constituent units derived from alkyl (meth)acrylate in which the hydrogen atoms of the alkyl group are substituted with hydroxyl groups. A photosensitive resin laminate according to any one of items 1 to 11, wherein the content of constituent units derived from alkyl (meth)acrylate in which the hydrogen atoms of the alkyl group are substituted with hydroxyl groups is in the range of 1% by mass or more and 20% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less.

[13] A photosensitive resin laminate according to any one of items 1 to 12, wherein the acid value of the (A) binder polymer is 155 mg KOH / g or less.

[14] A photosensitive resin laminate according to any one of items 1 to 13, wherein the copolymer having a weight-average molecular weight of 30,000 or less has an acid value of 155 mg KOH / g or less and has constituent units derived from styrene and styrene derivatives, and the content of constituent units derived from styrene and styrene derivatives is in the range of 35% by mass or more and 50% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less.

[15] The photosensitive resin laminate according to any one of items 1 to 14, wherein the copolymer having a weight-average molecular weight of 30,000 or less further has constituent units derived from methyl (meth)acrylate, and the content of the constituent units derived from methyl (meth)acrylate is in the range of 20% by mass or more and 50% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less.

[16] The photopolymerizable compound having an ethylenically unsaturated bond contains the following general formula (1): (In the formula, R 1 Each is independently a hydrogen atom or a methyl group, and X 1 O and Y 1 O is independently an oxyethylene group, an oxypropylene group, or an oxybutylene group, and m1, m2, n1, and n2 are the X contained in the compound, respectively. 1 O or Y 1A photosensitive resin laminate according to any one of items 1 to 15, containing 10% by mass or more of bisphenol A type di(meth)acrylate represented by (B) (where m1 + m2 + n1 + n2 is 0 to 9).

[17] A photosensitive resin laminate according to any one of items 1 to 16, wherein the (B) photopolymerizable compound having an ethylenically unsaturated bond contains 60% by mass or more of a compound containing an aromatic ring.

[18] A photosensitive resin laminate according to item 16, wherein the (B) photopolymerizable compound having an ethylenically unsaturated bond contains 10% by mass or more of bisphenol A type di(meth)acrylate in the general formula (1) where m1 + m2 + n1 + n2 is 4 or less.

[19] The photosensitive resin laminate according to any one of items 1 to 18, wherein the photosensitive resin layer further contains (E) a hydrogen donor, and the mass ratio of the content of (E) the hydrogen donor to the content of (C) the photopolymerization initiator (content of (E) the hydrogen donor / content of (C) the photopolymerization initiator) is 0.07 or more.

[20] The photosensitive resin laminate according to any one of items 1 to 19, wherein the absolute value of the difference between the absorbance for light at a wavelength of 365 nm and the absorbance for light at 402 nm per 1 μm thickness of the photosensitive resin composition is 0.018 or less.

[21] The photosensitive resin laminate according to any one of items 1 to 20, wherein the photosensitive resin composition contains (D) a polymerization inhibitor, the (D) polymerization inhibitor contains a polymerization inhibitor having two or more phenolic hydroxyl groups, and the content is 0.025 parts by mass or more per 100 parts by mass of the total amount of the (A) binder polymer and the (B) photopolymerizable compound.

[22] The photosensitive resin laminate according to any one of items 1 to 21, used to form a pattern with a line width and / or space width of 2 μm or less.

[23] The photosensitive resin laminate according to any one of items 1 to 22, wherein the absorbance of light with a wavelength of 365 nm per 1 μm thickness of the photosensitive resin layer is greater than 0.005 and 0.040 or less, and is intended to be exposed to light having a maximum wavelength of 355 to 375 nm.

[24] The photosensitive resin laminate according to any one of items 1 to 23, wherein the absorbance of the photosensitive resin layer per 1 μm thickness with respect to light having a wavelength of 402 nm is greater than 0.005 and not more than 0.040, and is for exposure by light having a maximum wavelength in the range of 395 to 410 nm.

[25] A photosensitive element comprising the photosensitive resin laminate according to any one of items 1 to 24 and an intermediate layer, having a laminated structure in which the temporary support, the intermediate layer, and the photosensitive resin layer are sequentially laminated.

[26] A method for forming a resist pattern, including laminating the photosensitive element according to item 25 on the surface of a metal plate or a metal-coated insulator, peeling the temporary support, performing exposure with ultraviolet light, and removing unexposed portions by development.

[27] A method for manufacturing a conductor pattern, including etching or plating a substrate on which a resist pattern is formed by the method according to item 26.

[28] The photosensitive resin laminate according to any one of items 1 to 24, wherein the photosensitive resin laminate further includes a protective film on the side opposite to the temporary support with respect to the photosensitive resin layer, and the protective film is a polyester film with a release layer.

[29] The photosensitive resin laminate according to any one of items 1 to 24, wherein the photosensitive resin laminate further includes a protective film on the side opposite to the temporary support with respect to the photosensitive resin layer, and the protective film is a biaxially stretched polypropylene film.

[0010] According to the present disclosure, it is possible to provide a photosensitive resin laminate and a photosensitive element capable of achieving both high adhesion and high resolution, and a method for forming a resist pattern and a method for manufacturing a conductor pattern using the photosensitive element.

[0011] A plan view showing the configuration of a drawing pattern related to this example. A plan view showing the configuration of a drawing pattern related to this example.

[0012] Hereinafter, embodiments of the present disclosure will be described. The present disclosure is not limited to the following embodiments and can be variously modified and implemented within the scope of the gist.

[0013] In this specification, if there are multiple structures represented by the same reference numeral in the same formula, unless otherwise specified, each structure may be selected independently and may be identical or different from one another. Similarly, if there are multiple structures represented by the same reference numeral in different formulas, unless otherwise specified, each structure may be selected independently and may be identical or different from one another.

[0014] Furthermore, in this specification, the upper or lower limits in the stepped numerical ranges may be replaced with the upper or lower limits in the corresponding other stepped numerical ranges, and may also be replaced with the corresponding values ​​described in the examples.

[0015] Furthermore, in this specification, "(meth)acrylic" means "acrylic" and / or "methacrylic," "(meth)acrylate" means "acrylate" and / or "methacrylate," and "(meth)acryloyl" means "acryloyl" and / or "methacryloyl." A "(meth)acryloyl group compound" is referred to, for example, as a "(meth)acrylate compound."

[0016] Furthermore, within this specification, the term "process" is included not only in the case of an independent process, but also in cases where it cannot be clearly distinguished from other processes, as long as the function of that process is achieved. In the drawings, the scale, shape, and length may be exaggerated for the sake of clarity.

[0017] Furthermore, in this specification, "solid content" of a photosensitive resin composition refers to the components of the photosensitive resin composition other than the solvent. The measurement methods for the physical properties and parameters described herein refer to the methods described in the examples.

[0018] Furthermore, unless otherwise specified in this specification, "adhesion" refers to the adhesion performance of the resist pattern to the substrate; "resolution" refers to the resolution performance of the resist pattern; "developability" also refers to the developability of the photosensitive resin layer (resist); and "sensitivity" refers to the exposure sensitivity of the photosensitive resin layer (resist).

[0019] Photosensitive resin laminate The photosensitive resin laminate of this disclosure comprises a temporary support layer and a photosensitive resin layer containing a photosensitive resin composition, wherein the photosensitive resin composition contains the following components: (A) a binder polymer, (B) a photopolymerizable compound having an ethylenically unsaturated bond, and (C) a photopolymerization initiator.

[0020] In the photosensitive resin laminate according to this disclosure, the average thickness of the photosensitive resin layer is 16 μm or less, (A) the binder polymer contains a copolymer having a weight-average molecular weight of 30,000 or less, (C) the content of the photopolymerization initiator is 5.0 parts by mass or more per 100 parts by mass of the total amount of (A) the binder polymer and (B) the photopolymerizable compound, and the absorbance for light at wavelengths of 365 nm and 402 nm per 1 μm of thickness of the photosensitive resin composition layer is greater than 0.005 and 0.040 or less.

[0021] The photosensitive resin laminate according to this disclosure tends to achieve both high adhesion and high resolution when forming fine line widths and / or space widths (e.g., 2 μm or less) by specifying the average thickness of the photosensitive resin layer, (A) the weight-average molecular weight of the binder polymer, (B) the content of the photopolymerizable compound, and the absorbance per 1 μm of the photosensitive resin composition layer as described above. This tendency is particularly pronounced when the average thickness of the photosensitive resin layer is 16 μm or less.

[0022] By setting the average thickness of the photosensitive resin layer to 16 μm or less, the aspect ratio is relaxed compared to when the thickness is 25 μm, making it possible to form finer patterns.

[0023] (A) By including a copolymer with a weight-average molecular weight of 30,000 or less in the binder polymer, swelling during development can be suppressed, which has an improved effect on adhesion and resolution, especially in fine patterns.

[0024] (C) By setting the content of the photopolymerization initiator to 5.0 parts by mass or more per 100 parts by mass of the total amount of (A) binder polymer and the (B) photopolymerizable compound, the concentration of active radicals generated by exposure increases, improving the initial rate of monomer polymerization, and as a result, improving the monomer reaction rate at the end. This has an effect of improving image formation performance that is greater than the increase in sensitivity.

[0025] The absorbance for light at a wavelength of 365 nm and the absorbance for light at 402 nm per 1 μm thickness of the photosensitive resin layer are preferably greater than 0.005 and 0.040 or less, more preferably greater than 0.008 and 0.040 or less, more preferably greater than 0.010 and 0.040 or less, even more preferably greater than 0.010 and 0.030 or less, and particularly preferably greater than 0.010 and 0.025 or less.

[0026] When forming a resist pattern using the photosensitive element of the present invention, the effect of achieving both high adhesion and high resolution is presumed to be well achieved by setting the absorbance at a wavelength close to the exposure wavelength within the above range. That is, it is more preferable to set the absorbance at a wavelength close to the exposure wavelength among 365 nm and 402 nm within the above range, and it is even more preferable to set both the absorbance for light at a wavelength of 365 nm and the absorbance for light at 402 nm within the above range.

[0027] When the absorbance of the photosensitive resin layer per 1 μm thickness for light with a wavelength of 365 nm is greater than 0.005 and less than or equal to 0.040, the photosensitive resin laminate is preferably used in applications where it is exposed to light having a maximum wavelength in the range of 355 to 375 nm, and is particularly preferably used in applications where it is exposed to i-line (365 nm) light.

[0028] When the absorbance of the photosensitive resin layer per 1 μm thickness for light with a wavelength of 402 nm is greater than 0.005 and less than or equal to 0.040, the photosensitive resin laminate is preferably used in applications where it is exposed to light having a maximum wavelength of 395 to 410 nm, and in particular, it is preferably used in applications where it is exposed to h-rays, or to light having a maximum wavelength of 395 to 410 nm, such as an InGaN semiconductor laser.

[0029] From the viewpoint of improving the controllability of the reaction during exposure, a small difference in absorbance for wavelengths of 365 nm and 402 nm is preferable, more preferably 0.010, and particularly preferable 0.005 per 1 μm thickness of the photosensitive resin layer.

[0030] By reducing absorbance in two wavelength bands, 365 nm and 402 nm, energy can be efficiently transferred from the sensitizer to the initiator regardless of which wavelength light source is used. As a result, efficient curing becomes possible even when exposure is performed using semiconductor lasers with different wavelengths, allowing the use of exposure machines with a wide range of wavelengths.

[0031] The absorbance of the photosensitive resin layer per 1 μm thickness for light at a wavelength of 365 nm and for light at a wavelength of 402 nm can be controlled to the above range by controlling the type and amount of the photopolymerization initiator and / or sensitizer described later (C).

[0032] When a thin photosensitive resin layer with an average thickness of 16 μm or less is used, the light transmittance during exposure increases, resulting in a greater amount of light reaching the substrate surface. As a result, light that is not absorbed when passing through the photosensitive resin layer is reflected at the substrate surface, leading to hardening of the resist in the unexposed areas. In particular, when the content of (C) photopolymerization initiator is set to 5.0 parts by mass or more per 100 parts by mass of the total amount of (A) binder polymer and the (B) photopolymerizable compound in order to improve image formation, the hardening reaction is accelerated by the reaction acceleration in the exposed areas, but at the same time, the exposure sensitivity of the resist in the unexposed areas increases, and the adverse effect of hardening of the resist in the unexposed areas due to light reflected at the substrate surface becomes significant. Furthermore, if (A) the binder polymer contains a copolymer with a weight-average molecular weight of 30,000 or less, the movement of (B) the photopolymerizable compound having an ethylenically unsaturated bond tends to be relatively free in the reaction system, and it is estimated that this increases the frequency with which the photopolymerizable compound having an ethylenically unsaturated bond comes into contact with other active radical species, making it easier for the resist in unexposed areas to harden due to light reflected from the substrate surface. Therefore, it is estimated that by increasing the absorbance of the photosensitive resin layer, the amount of light reaching the substrate surface is reduced, and hardening of the unexposed areas is suppressed, thereby further improving transparency and resolution.

[0033] In particular, in the photosensitive resin laminate according to this disclosure, if the weight-average molecular weight, the content of (C) photopolymerization initiator, and the absorbance for light at wavelengths of 365 nm and 402 nm per 1 μm thickness of the photosensitive resin composition layer are all within a specific range, a synergistic effect of improved image formation and suppression of hardening of the resist in unexposed areas can be obtained, and it tends to be possible to achieve both high adhesion and high resolution when forming fine patterns with line widths and / or space widths, especially when forming patterns with line widths and / or space widths of 2 μm or less.

[0034] The photosensitive resin laminates of this disclosure are suitably used in the manufacture of conductor patterns. For example, the photosensitive resin laminates of this disclosure can be suitably used in the manufacture of printed circuit boards; lead frames for mounting IC chips; metal foils such as metal masks; packages such as ball grid arrays (BGAs) and chip-size packages (CSPs); tape substrates such as chip-on-film (COF) and tape-automated bonding (TAB); semiconductor bumps; organic interposers; and partitions for flat panel displays such as ITO electrodes, address electrodes, and electromagnetic shields.

[0035] If desired, the photosensitive resin laminate may consist only of a temporary support and a photosensitive resin layer, or it may include a protective layer such as a protective film in addition to the temporary support and the photosensitive resin layer. The photosensitive resin laminate may have a protective layer on the side of the temporary support layer opposite to the photosensitive resin layer. In this case, a photosensitive resin laminate having a temporary support layer, a photosensitive resin layer, and a protective layer is provided.

[0036] A photosensitive resin laminate may have layers other than the temporary support layer, the photosensitive resin layer, and the protective layer (other layers). Examples of other layers include an "intermediate layer" placed between the temporary support layer and the photosensitive resin layer, and / or between the photosensitive resin layer and the protective layer. For example, a photosensitive resin laminate having an intermediate layer between the temporary support layer and the photosensitive resin layer is manufactured by applying a coating liquid to the intermediate layer on the temporary support layer to form a coating film, and then drying the coating film to obtain the photosensitive resin layer. Another example of other layers is a "release layer" placed on the side of the protective layer opposite to the photosensitive resin layer.

[0037] The temporary support layer, the photosensitive resin layer, and / or protective layer may each consist of a single layer or multiple layers. If they consist of multiple layers, their total thickness may be treated as the thickness of that layer.

[0038] The components of the photosensitive resin laminate relating to this disclosure are described below.

[0039] [Temporary Support] The temporary support is a substrate for supporting the photosensitive resin layer and is also called a "support film." The temporary support may be in the form of a layer for supporting the photosensitive resin layer, and it is preferable that it is transparent to the extent that it can transmit exposure light (active light) emitted from the exposure light source. The temporary support is peeled off from the photosensitive resin layer before the exposure process in which the photosensitive resin layer is exposed, or before the development process in which the photosensitive resin layer is developed.

[0040] Suitable substrates for use as temporary supports, particularly transparent substrates, include synthetic resins such as polyethylene, polypropylene, polycarbonate, and polyethylene terephthalate. Of these, polyethylene terephthalate (PET) is preferred as a temporary support because it possesses moderate flexibility and strength. The temporary support may be stretched as needed.

[0041] The absorbance of the temporary support at a wavelength of 365 nm is preferably 0.3 or less, more preferably 0.2 or less, even more preferably 0.1 or less, and most preferably 0.08 (e.g., 0.080) or less. The above absorbance may be 0 or greater.

[0042] It is preferable to use a film with few internal foreign matter, such as a high-quality film, as a temporary support. Examples of high-quality films include PET films synthesized using a Ti-based catalyst, PET films with small lubricant diameters and low lubricant content, PET films containing lubricant on only one side, thin-film PET films, PET films with smoothing treatment on at least one side, and PET films with roughening treatment such as plasma treatment on at least one side. By using a high-quality film as a temporary support, exposure light is less likely to be blocked by internal foreign matter in the temporary support, making it easier to irradiate the photosensitive resin layer with exposure light, and as a result, resolution tends to improve.

[0043] When the temporary support is in the form of a temporary support layer, the thickness of the temporary support layer is preferably 5 to 25 μm, and more preferably 6 to 20 μm. By adjusting the thickness of the temporary support layer within this range, it is easier to reduce the number of internal foreign matter, and therefore easier to prevent a decrease in resolution. In addition, it is easier to ensure the strength of the temporary support layer, and therefore easier to prevent wrinkles from forming in the photosensitive resin layer during the manufacturing process of the photosensitive resin laminate and / or when laminating the photosensitive resin laminate onto the substrate.

[0044] The haze of the temporary support is preferably 0.01 to 1.5%, more preferably 0.01 to 1.2%, and even more preferably 0.01 to 0.95%, from the viewpoint of improving the parallelism of the exposure light irradiated onto the photosensitive resin layer and obtaining good resolution.

[0045] [Protective Layer] The protective layer is a layer for protecting the photosensitive resin layer, and is often in the form of a film, also called a "protective film." The protective layer is provided on the side opposite the temporary support (support film) to the photosensitive resin layer and has an appropriate adhesion force to the photosensitive resin layer. When the adhesion force between the photosensitive resin layer and the protective layer is sufficiently smaller than the adhesion force between the photosensitive resin layer and the temporary support, the protective layer can be easily peeled off from the photosensitive resin layer. The photosensitive resin layer exposed by peeling off the protective layer is laminated onto the substrate in the lamination process described later.

[0046] Examples of protective layers include polyethylene film, polypropylene film, oriented polypropylene film, biaxially oriented polypropylene film, and polyester film. Specifically, examples of protective layers include Alphan® EM-501, E-200, E-200C3, E-201F, FG-201, MA-411 (all manufactured by Oji F-Tex Co., Ltd.), Trefan® KW37, 2578, 2548, 2500, YM17S, Therapiel® PJ271, PJ111, HP2, PJ101, WZ, MDA, MFA, TK07, BKE, BX8A, SY (all manufactured by Toray Industries, Inc.), GF-18, GF-818, GF-858 (all manufactured by Tamapoly Co., Ltd.).

[0047] The thickness of the protective layer is preferably 10 to 100 μm, and more preferably 15 to 50 μm. This makes it easier to ensure the marketability and handling of the photosensitive resin laminate, and also makes it easier to realize a photosensitive resin laminate roll by winding (rolling) the photosensitive resin laminate of this disclosure.

[0048] The protective layer may have a release layer on its surface, in which case the protective layer is easily peeled off from the photosensitive resin layer. The compounds constituting this type of release layer are classified, for example, into silicone compounds and non-silicone compounds.

[0049] Examples of silicone compounds include: condensation reaction type silicone resins obtained by reacting terminally silanol polydimethylsiloxane with polymethylhydrogen siloxane or polymethylmethoxysiloxane; addition reaction type silicone resins obtained by reacting dimethylsiloxane-methylvinylsiloxane copolymer or dimethylsiloxane-methylhexenylsiloxane copolymer with polymethylhydrogen siloxane; UV-curable or electron-beam-curable silicone resins obtained by curing acrylic silicone and epoxy group-containing silicone with ultraviolet light or electron beams; modified silicone resins such as epoxy-modified silicone resin (silicone epoxy), polyester-modified silicone resin (silicone polyester), acrylic-modified silicone resin (silicone acrylic), phenol-modified silicone resin (silicone phenol), alkyd-modified silicone resin (silicone alkyd), and melamine-modified silicone resin (silicone melamine); and the like.

[0050] Examples of non-silicone compounds include alkyd resins, long-chain alkyl resins, acrylic resins, and polyolefin resins.

[0051] Examples of protective layers with a release layer include polyester films with a release layer, specifically the "X2NY" release film manufactured by Toyobo Film Solutions Co., Ltd.

[0052] The thickness of the release layer is preferably 0.001 to 2 μm, more preferably 0.005 to 1 μm, and even more preferably 0.01 to 0.5 μm. This may result in advantages such as a good appearance of the coating film, easier curing of the coating film, and easier securing of sufficient release properties.

[0053] [Photosensitive resin layer] The photosensitive resin layer constitutes the photosensitive resin laminate of this disclosure. The photosensitive resin layer comprises a photosensitive resin composition comprising the following components: (A) a binder polymer, (B) a photopolymerizable compound having an ethylenically unsaturated bond, and (C) a photopolymerization initiator. In this specification, these components are described as "component (A)," etc. Optionally, the photosensitive resin composition may further contain components other than components (A) to (C), such as (D) a polymerization inhibitor, (E) a hydrogen donor, antioxidant, stabilizer, base dye, solvent, etc., and each component and / or the raw material of each component may be used alone or in combination of two or more.

[0054] (Content of various components) From the viewpoint of easily achieving the effects of this disclosure, or from the viewpoint of suitability for forming a conductive pattern, the total content of component (A) and component (B) in the photosensitive resin composition is preferably 80% by mass or more, and more preferably 90% by mass or more, based on the solid content of the photosensitive resin composition.

[0055] (Thickness) The average thickness of the photosensitive resin layer is more preferably 16 μm or less, even more preferably 10 μm or less, and particularly preferably 7 μm or less, from the viewpoint of achieving both high adhesion and high resolution for patterns with fine line widths and / or space widths. Furthermore, from the viewpoint of suitability for etching and plating processes after resist pattern formation, the average thickness of the photosensitive resin layer is preferably 3 μm or more, and even more preferably 5 μm or more. The lower limit of the average thickness of the photosensitive resin layer is not limited, but may be, for example, greater than 0 μm or greater than 1 μm.

[0056] A photosensitive resin layer with an average thickness of 16 μm or less is more preferably used in providing a photosensitive element having a laminated structure in which a support film, an intermediate layer, and the photosensitive resin layer are sequentially laminated, as described later.

[0057] <Component (A): Binder Polymer> Component (A) is a binder polymer, and from the viewpoint of forming a resist pattern, it may be a polymer soluble in an alkaline aqueous solution.

[0058] (A) Component (A) preferably has a carboxyl group and preferably has an acid value of 50 to 600 mg KOH / g, from the viewpoint of exhibiting suitable alkali solubility.

[0059] (A) The acid value of component (A) may be 60 mg KOH / g or more, preferably 80 mg KOH / g or more, and more preferably 100 mg KOH / g or more, from the viewpoint of developability. (A) The acid value of component (A) may be 250 mg KOH / g or less, preferably 200 mg KOH / g or less, more preferably 180 mg KOH / g or less, particularly preferably 165 mg KOH / g or less, more preferably 155 mg KOH / g or less, even more preferably 140 mg KOH / g or less, and most preferably 125 mg KOH / g or less, from the viewpoint of suppressing swelling in the development process of the photosensitive resin laminate and photosensitive element and further improving adhesion. (A) The acid value of component (A) may be 250 mg KOH / g or less, preferably 200 mg KOH / g or less, more preferably 180 mg KOH / g or less, particularly preferably 165 mg KOH / g or less, more preferably 155 mg KOH / g or less, even more preferably 140 mg KOH / g or less, and most preferably 125 mg KOH / g or less. By setting the acid value of component (A) within the above range, swelling can be suppressed while maintaining developability, and good resolution can be obtained with fine patterns.

[0060] The acid value can be calculated by accurately weighing approximately 1 g of the sample, dissolving it in 100 mL of acetone, and then performing a neutralization titration with a 1 mol / L potassium hydroxide solution. The acid value (mgKOH / g) is then calculated based on the volume of potassium hydroxide solution added using the following formula: Acid value (mgKOH / g) = 56.1 × {Volume of 1 mol / L potassium hydroxide solution added (mL)} / {Mass of accurately weighed sample (g)}. The neutralization titration can be performed, for example, using a Hiranuma automatic titrator (COM-555) manufactured by Hiranuma Sangyo Co., Ltd.

[0061] Furthermore, the hydroxyl value of component (A), described later, can be determined by accurately weighing approximately 1 g of the sample, dissolving it in 100 mL of pyridine / acetone mixed solvent (volume ratio 1:1), adding an excess of acetic anhydride to acetylate it, and then titrating the remaining acetic anhydride after the reaction with a 1 mol / L potassium hydroxide aqueous solution. Simultaneously, a blank (acetic anhydride treated under the same conditions) without the sample is also titrated in the same manner, and the hydroxyl value is calculated from the difference between the blank titration volume and the sample titration volume. Based on the amount of potassium hydroxide aqueous solution added for each titration, the hydroxyl value can be calculated using the following formula: Hydroxyl value (mgKOH / g) = 56.1 × {Blank titration volume (mL) - Sample titration volume (mL)} / {Mass of accurately weighed sample (g)}. Neutralization titration can be performed, for example, using a Hiranuma automatic titrator (COM-555) manufactured by Hiranuma Sangyo Co., Ltd.

[0062] The acid value of component (A) is controlled by the content of compounds (A-1), (A-2), and (A-3) that have an acid group, as described below.

[0063] Component (A) is preferably composed of multiple types of constituent units, more preferably of three or more types of constituent units, from the viewpoint of achieving both high adhesion and high resolution, and is even more preferably composed of all constituent units derived from each of the following (A-1) to (A-3): (A-1) (meth)acrylic acid (A-2) a compound having an aromatic ring and an ethylenically unsaturated bond (A-3) a compound that does not fall under (A-1) or (A-2);

[0064] In other words, component (A) is preferably composed of monomer copolymers (hereinafter simply referred to as copolymers) corresponding to one or more constituent units corresponding to (A-1) to (A-3) above. For example, component (A) may include copolymers containing all the constituent units corresponding to each of (A-1) to (A-3), and component (A) may include copolymers containing constituent units derived from (A-1) and (A-2) and copolymers containing constituent units derived from (A-1) and (A-3).

[0065] Regarding the content ratio of the constituent units derived from (A-1) to (A-3) above, from the viewpoint of achieving both high adhesion and high resolution, it is preferable that the proportions of the constituent units derived from (A-1), (A-2), and (A-3) relative to the total mass of component (A) be 10 to 30% by mass, 20 to 80% by mass, and 0 to 60% by mass, respectively. The proportion of each constituent unit means the weighted average value of the copolymerization ratio of each constituent unit, weighted by the content ratio of each binder polymer. Similarly, each value described for component (A) (for example, weight-average molecular weight and polydispersity, etc.) also means the weighted average value, weighted by the content ratio of each binder polymer.

[0066] Component (A) is preferably formed using monomers of each of the above compounds (A-1), (A-2), and (A-3).

[0067] The above compound (A-1) is (meth)acrylic acid.

[0068] The above (A-2) compound includes styrene, styrene derivatives, benzyl (meth)acrylate, nonylphenoxypolyethylene glycol (meth)acrylate, phenoxyethyl (meth)acrylate, and 2-[3-(2H-benzotriazole-2-yl)-4-hydroxyphenyl]ethyl (meth)acrylate. Examples of styrene derivatives include methylstyrene, vinyltoluene, tert-butoxystyrene, acetoxystyrene, 4-vinylbenzoic acid, styrene dimer, and styrene trimer. In particular, from the viewpoint of easily achieving the effects of this disclosure or being suitable for forming a conductive pattern, the (A-2) compound is preferably at least one selected from benzyl (meth)acrylate, styrene, and styrene derivatives, and more preferably styrene.

[0069] If component (A) contains constituent units derived from (A-2) above, the proportion of constituent units derived from (A-2) in component (A) is preferably 35 to 90% by mass, based on the total mass of all monomer components.

[0070] Setting the ratio to 35% by mass or more is preferable from the viewpoint of excellent adhesion and resolution, 40% by mass or more is more preferable, 50% by mass or more is even more preferable, 60% by mass or more is particularly preferable, and 70% by mass or more is most preferable. Setting the ratio to 90% by mass or less is preferable from the viewpoint of excellent developability, and 85% by mass or less is more preferable. When component (A) contains multiple types of component (A-2), it is preferable that the total value of each component (A-2) is within the above range.

[0071] When component (A) contains constituent units derived from styrene, the proportion of constituent units derived from styrene in component (A) is preferably 35% by mass or more, based on the total mass of all monomer components. This makes it easier to achieve the effects of the present disclosure. From a similar viewpoint, it is more preferable that the proportion of constituent units derived from styrene be 40% by mass or more, more preferably 50% by mass or more, and even more preferably 60% by mass or more. The proportion of constituent units derived from styrene may be 90% by mass or less.

[0072] When using a mixture of two or more components (A), it is preferable that the weighted average value, when the content ratio of each component (A) in the proportion of constituent units derived from (A-2) or styrene in the multiple (A) components is treated as a weight, falls within the above range.

[0073] (A) By setting the proportion of aromatic rings and styrene contained in component (A) within the above range, swelling in the developing solution is suppressed, and a photosensitive resin laminate with excellent resolution and adhesion can be obtained.

[0074] Examples of the above (A-3) compounds include fumaric acid, crotonic acid, itaconic acid, maleic anhydride, maleic acid semi-ester, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, glycerin mono (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and dicyclopentenyloxyethyl (meth)acrylate. Examples include isobornyl (meth)acrylate, pentamethylpiperidyl (meth)acrylate, tetramethylpiperidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, ethyl carbitol (meth)acrylate, methoxyethyl (meth)acrylate, methoxytriethylene glycol (meth)acrylate, poly(ethylene glycol) methyl ether (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, vinyl alcohol esters (e.g., vinyl acetate), (meth)acrylonitrile, etc.

[0075] Among the compounds described above, from the viewpoint of easily achieving the effects of this disclosure or being suitable for forming a conductive pattern, compound (A-3) preferably contains an alkyl (meth)acrylate, and more preferably contains, for example, a methyl (meth)acrylate.

[0076] (A-3) When compound (A-3) contains alkyl (meth)acrylate, the alkyl (meth)acrylate content is preferably 20 to 60% by mass from the viewpoint of the flexibility of the binder polymer. For example, when compound (A-3) contains methyl (meth)acrylate, the methyl (meth)acrylate content is preferably 20 to 60% by mass.

[0077] (A) The binder polymer may include copolymers having structural units derived from alkyl (meth)acrylates in which the hydrogen atoms of the alkyl group are substituted with hydroxyl groups. (A) The inclusion of structural units derived from alkyl (meth)acrylates in which the hydrogen atoms of the alkyl group are substituted with hydroxyl groups in the binder polymer increases the development speed, thereby expanding the range of use for other high-performance raw materials with slower development speeds, and as a result, improving developability and image formation. Examples of alkyl (meth)acrylates in which the hydrogen atoms of the alkyl group are substituted with hydroxyl groups include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate, as well as glycerin mono (meth)acrylate.

[0078] The weight-average molecular weight (Mw) of component (A) is preferably 10,000 to 30,000. A weight-average molecular weight of 30,000 or less is preferable from the viewpoint of achieving both adhesion and resolution of the resist pattern, more preferably 25,000 or less, and even more preferably 20,000 or less.

[0079] When using a mixture of multiple types of component (A), the weight-average molecular weight of one or all of the components (A) is 30,000 or less. The proportion of component (A) with a weight-average molecular weight of 30,000 or less (polymer with a weight-average molecular weight of 30,000 or less) is preferably 30% by mass or more, more preferably 50% by mass or more, and most preferably 90% by mass or more, of the total amount of component (A). By including component (A) with a weight-average molecular weight of 30,000 or less in the above proportions, the adhesion and resolution of patterns with fine line widths or space widths are improved.

[0080] In this disclosure, (A) the weight-average molecular weight (Mw) of the binder polymer is measured using gel permeation chromatography (GPC). That is, the sample is dissolved in a suitable solvent and filtered, then subjected to a GPC apparatus, and the weight-average molecular weight is measured by obtaining a molecular weight distribution curve by performing molecular weight calibration on the obtained chromatogram. Detailed experimental conditions follow, for example, the method described in the examples below.

[0081] In this disclosure, (A) when the binder polymer is composed of multiple types of binder polymers, multiple molecular weight regions are defined in the molecular weight distribution based on the weight-average molecular weight, and the chromatogram area corresponding to each region is calculated. Since each binder polymer appears in a region with a characteristic weight-average molecular weight in the molecular weight distribution, the component ratio in the mixture can be objectively determined based on the area ratio distribution of this region.

[0082] The weight percentage Wi (mass%) of binder polymer species i corresponding to each of the multiple binder polymer species (1, 2, ..., n) is calculated using the molecular weight distribution curve by the following formula: Wi = Ai / ΣAj × 100, where Ai is the GPC chromatogram area in the molecular weight region corresponding to the weight-average molecular weight Mwi, j is an integer greater than or equal to 1, and the value of ΣAj is 1.

[0083] This method is reproducible by a third party as long as the measurement conditions (column, solvent, flow rate, temperature, and detector, etc.) are kept constant. It can determine the composition ratio based on the molecular weight distribution, independent of the properties of the polymer species constituting the mixed system. Furthermore, the accuracy of molecular weight calculation and component identification can be further improved by using multi-angle light scattering (MALS) detectors or UV detectors as needed.

[0084] In this disclosure, it is preferable that the balance between hydrophilicity and hydrophobicity of the copolymer having a weight-average molecular weight of 30,000 or less is within an appropriate range. Among the above constituent units, examples of constituent units that make the copolymer component contained in the binder polymer (A) particularly hydrophilic include (A-1) (meth)acrylic acid and compounds containing acid groups and / or hydroxyl groups in component (A-3). Among the above constituent units, examples of constituent units that make the copolymer component contained in the binder polymer (A) particularly hydrophobic include styrene and styrene derivatives in component (A-2). It is presumed that an appropriate balance between hydrophilicity and hydrophobicity makes it possible to prevent swelling of the photosensitive resin layer in the exposed area while maintaining the developability of the photosensitive resin layer in the unexposed area within an appropriate range when forming patterns with fine line widths and / or space widths, thereby contributing to achieving both resolution and adhesion.

[0085] Examples of a copolymer with a weight-average molecular weight of 30,000 or less in which the balance between hydrophilicity and hydrophobicity is within an appropriate range include a copolymer in which the value obtained by the following formula: (acid value (mgKOH / g) + hydroxyl value (mgKOH / g)) / (parts by mass of constituent units derived from monomers having aromatic rings per 100 parts by mass of copolymer with a weight-average molecular weight of 30,000 or less) is between 2.2 and 3.6. Preferably, the above value is between 2.4 and 3.6, and more preferably between 2.7 and 3.4.

[0086] More specifically, the following two embodiments are preferred for a copolymer having a weight-average molecular weight of 30,000 or less in which the balance between hydrophilicity and hydrophobicity is within an appropriate range: (Embodiment 1) The copolymer has an acid value of 100 mg KOH / g or more and 250 mg KOH / g or less, and / or has constituent units derived from polymerizable monomers having hydroxyl groups, and the proportion of constituent units derived from styrene and styrene derivatives is 35% by mass or more and 70% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less. (Embodiment 2) The copolymer has an acid value of 70 mg KOH / g or more and 155 mg KOH / g or less, and the proportion of constituent units derived from styrene and styrene derivatives is 35% by mass or more and 50% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less.

[0087] In (Embodiment 1), the polymerizable monomer having a hydroxyl group is preferably an alkyl (meth)acrylate in which the hydrogen atom of the alkyl group is substituted with a hydroxyl group, and more preferably a hydroxyethyl (meth)acrylate. The content of constituent units derived from these polymerizable monomers is preferably in the range of 1% by mass or more and 20% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less.

[0088] In (Aspect 2), from the viewpoint of dimensional stability and residue reduction, it is further preferable that Tg be 115°C or higher. In (Aspect 2), means of making Tg 115°C or higher include, for example, but are not limited to, a method in which the proportion of constituent units derived from methyl (meth)acrylate is 20% by mass or more and 50% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less.

[0089] In this specification, (A) the Tg of the copolymer contained in the alkali-soluble resin is determined by the Fox formula described below. For a copolymer consisting of n monomers, the Fox formula for calculating the Tg (K: Kelvin) of the copolymer is as follows: {In the formula, Tg ｉ(K: Kelvin) is the glass transition temperature of a homopolymer composed of each monomer, c ｉ This is expressed by the copolymerization ratio of each monomer.

[0090] In this disclosure, the Tg value of homopolymers composed of monomers forming alkali-soluble polymers is taken from literature (Brandrup, J. Immergut, E. H. eds., Polymer Handbook, Third Edition, John Wiley & Sons, 1989, Chapter VI “GLASS transition temperatures of polymers”, p209). ｉ An example of this is as follows:

[0091] For example, the Tg of A-7: methacrylic acid / styrene / methyl methacrylate (mass ratio: 21 / 40 / 39) is 123°C, and the Tg of A-8: methacrylic acid / styrene / methyl methacrylate (mass ratio: 18 / 40 / 42) is 120°C.

[0092] The polydispersity of component (A) {weight-average molecular weight of component (A) (Mw) / number-average molecular weight of component (A) (Mn)} is preferably 1.0 to 6.0, more preferably 1.0 to 5.0, even more preferably 1.0 to 4.0, and particularly preferably 1.0 to 3.0.

[0093] (A) The content of component (A) is preferably 1 to 80% by mass, more preferably 1 to 70% by mass, and even more preferably 5 to 60% by mass, relative to the solid content of the photosensitive resin composition. When the content of component (A) is 1% by mass or more, excellent adhesion and fine line strength are easily achieved. When the content of component (A) is 80% by mass or less, resistance to developing solutions is easily ensured.

[0094] 《Synthesis of Component (A)》 Component (A) can be synthesized by diluting monomers corresponding to the one or more constituent units described above with a solvent such as acetone, methyl ethyl ketone, and isopropanol, mixing appropriate amounts of radical polymerization initiators such as benzoyl peroxide and azobisisobutyronitrile, and then heating and stirring. In some cases, component (A) can be synthesized by adding a portion of the mixture dropwise to the reaction solution. After the reaction is complete, the solvent may be further added to adjust to the desired concentration. In addition to solution polymerization, bulk polymerization, suspension polymerization, or emulsion polymerization may also be used as synthesis methods. Furthermore, synthesis may be carried out by living radical polymerization.

[0095] <Component (B): Photopolymerizable compound having an ethylenically unsaturated bond> Component (B) is a photopolymerizable compound having an ethylenically unsaturated bond, for example, a compound having one or more ethylenically unsaturated bonds in one molecule. Component (B) may contain multiple such compounds that are different from each other.

[0096] The ethylenically unsaturated bond in component (B) functions as a photopolymerizable bond. The compound having such an ethylenically unsaturated bond may be a compound containing a photopolymerizable functional group, for example, a compound containing a (meth)acryloyl group.

[0097] Regarding component (B), having "n" photopolymerizable functional groups in one molecule is sometimes referred to as "n-functional." For example, a compound having n (meth)acryloyl groups is sometimes referred to as an n-functional (meth)acrylate compound. For example, with respect to component (B), having one, two, three, four, five, or six photopolymerizable functional groups in one molecule is sometimes referred to as "monofunctional (or monofunctional)," "difunctional," "trifunctional," "tetrafunctional," "pentafunctional," or "hexafunctional," respectively.

[0098] Examples of the bifunctional (meth)acrylate compound include alkyldi(meth)acrylate, 1,3-bis(meth)acryloyloxy-2-propanol, polyalkylene glycol di(meth)acrylate, tricyclodecanol di(meth)acrylate, ethoxylated (hydrogenated) bisphenol A di(meth)acrylate, propoxylated (hydrogenated) bisphenol A di(meth)acrylate, and tetramethylene glycoloxylated (hydrogenated) bisphenol A di(meth)acrylate.

[0099] Examples of the polyalkylene glycol di(meth)acrylate include polyethylene glycol di(meth)acrylate, polypropylene di(meth)acrylate, and polytetramethylene glycol di(meth)acrylate. The polyalkylene glycol di(meth)acrylate may be a compound having a plurality of alkylene groups including an ethylene group, a propylene group, and a tetramethylene group as the alkylene group. Examples of the above compound include a di(meth)acrylate of a polyalkylene glycol obtained by adding an average of 3 ethylene oxides to each end of a polypropylene glycol containing an average of 12 propylene oxides; and a di(meth)acrylate obtained by adding an average of 6 propylene oxides to each end of 6 mol of ethylene oxide.

[0100] In this specification, the average number of alkylene oxides such as ethylene oxide and propylene oxide may be understood to be determined by number average, and catalog values may be referred to within a range not deviating from the above values for reference.

[0101] Further, examples of the bifunctional (meth)acrylate compound include the following general formula (1): (In the formula, R １ is independently a hydrogen atom or a methyl group, X １ O and Y １ O are independently an oxyethylene group or an oxypropylene group, and m1, m2, n1, and n2 are the X １ O or Y １Bisphenol A type di(meth)acrylates can also be cited, which are represented by the formula: (The average number of O atoms is shown, and each is an integer from 0 to 40, m1 + m2 is from 1 to 40, and n1 + n2 is from 0 to 20.)

[0102] Furthermore, examples of bifunctional (meth)acrylate compounds include: dimethacrylate of polyethylene glycol obtained by adding an average of 10 moles of ethylene oxide to bisphenol A (e.g., BPE-500, manufactured by Shin-Nakamura Chemical Co., Ltd.); dimethacrylate of polyethylene glycol obtained by adding an average of 4 moles of ethylene oxide to bisphenol A (e.g., BPE-200, manufactured by Shin-Nakamura Chemical Co., Ltd.); dimethacrylate of polyethylene glycol obtained by adding an average of 2.6 moles of ethylene oxide to bisphenol A (e.g., BPE-100, manufactured by Shin-Nakamura Chemical Co., Ltd.); dimethacrylate of polyethylene glycol obtained by adding an average of 2 moles of ethylene oxide to bisphenol A (e.g., SR348NS, manufactured by Sartomer Co., Ltd.); dimethacrylate of polypropylene glycol obtained by adding an average of 10 moles of propylene oxide to bisphenol A; and dimethacrylate of polypropylene glycol obtained by adding an average of 4 moles of propylene oxide to bisphenol A. In the above-mentioned bifunctional (meth)acrylate compounds, the average number of moles of ethylene oxide and propylene oxide indicates the number of moles per mole of compound.

[0103] Furthermore, it is preferable that component (B) contains a bisphenol A type di(meth)acrylate in which m1 + m2 + n1 + n2 is represented by values ​​from 0 to 9 in general formula (1). It is even more preferable that it contains a bisphenol A type di(meth)acrylate in which m1 + m2 + n1 + n2 is represented by values ​​from 0 to 4, and it is most preferable that it contains a bisphenol A type di(meth)acrylate in which m1 + m2 + n1 + n2 is represented by values ​​from 2 to 2.6.

[0104] Furthermore, the content of bisphenol A type di(meth)acrylate, where m1+m2+n1+n2 is represented by values ​​from 0 to 9, is preferably 10 to 100%, more preferably 15 to 75%, and most preferably 15 to 50% of the total amount of component (B). By setting it within the above range, swelling in the developing solution can be suppressed and pattern strength can be achieved by improving the crosslinking density, thereby improving the resolution and adhesion of fine patterns. From a similar viewpoint, the preferred content when component (B) contains bisphenol A type di(meth)acrylate, where m1+m2+n1+n2 is represented by values ​​from 0 to 4, is the same as above.

[0105] Examples of bisphenol A type di(meth)acrylates in general formula (1) where m1 + m2 + n1 + n2 are represented by values ​​from 0 to 9 include: polyethylene glycol dimethacrylate obtained by adding an average of 4 moles of ethylene oxide to bisphenol A (e.g., BPE-200, manufactured by Shin-Nakamura Chemical Co., Ltd.); polyethylene glycol dimethacrylate obtained by adding an average of 2.6 moles of ethylene oxide to bisphenol A (e.g., BPE-100, manufactured by Shin-Nakamura Chemical Co., Ltd.); polyethylene glycol dimethacrylate obtained by adding an average of 2 moles of ethylene oxide to bisphenol A (e.g., SR348NS, manufactured by Sartomer Co., Ltd.); and polypropylene glycol dimethacrylate obtained by adding an average of 4 moles of propylene oxide to bisphenol A.

[0106] Examples of trifunctional or more (meth)acrylate compounds include trimethylolpropane tri(meth)acrylate, glycerin tri(meth)acrylate, isocyanuric acid tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, diglycerin tetra(meth)acrylate, triglycerin penta(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, ditrimethylolpropane penta(meth)acrylate, ditrimethylolpropane hexa(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and tetraglycerin hexa(meth)acrylate.

[0107] Furthermore, examples of trifunctional or more (meth)acrylate compounds include compounds obtained by forming a (meth)acrylate from an alcohol having three or more groups in the molecule that can be to which alkylene oxide groups can be added as a central skeleton, to which alkylene oxide groups such as ethylene oxide groups, propylene oxide groups, or butylene oxide groups are to be added, and (meth)acrylic acid. Such compounds include alkylene oxide-modified tri(meth)acrylate of trimethylolpropane, alkylene oxide-modified tri(meth)acrylate of glycerin, alkylene oxide-modified pentaerythritol tri(meth)acrylate, alkylene oxide-modified pentaerythritol tetra(meth)acrylate, alkylene oxide-modified diglycerin tetra(meth)acrylate, alkylene oxide-modified triglycerin penta(meth)acrylate, and alkylene oxide-modified ditrimethylolpropane Examples include tetra(meth)acrylate, alkylene oxide-modified ditrimethylolpropane penta(meth)acrylate, alkylene oxide-modified ditrimethylolpropane hexa(meth)acrylate, alkylene oxide-modified dipentaerythritol tetra(meth)acrylate, alkylene oxide-modified dipentaerythritol penta(meth)acrylate, alkylene oxide-modified dipentaerythritol hexa(meth)acrylate, and alkylene oxide-modified isocyanuric acid tri(meth)acrylate. The alkylene oxide group is preferably an ethylene oxide group, a propylene oxide group, or a butylene oxide group.

[0108] As a trifunctional or more (meth)acrylate compound, from the viewpoint of excellent developability, it may include at least one selected from the group consisting of alkylene oxide-modified pentaerythritol tri(meth)acrylate, alkylene oxide-modified pentaerythritol tetra(meth)acrylate, alkylene oxide-modified dipentaerythritol tetra(meth)acrylate, alkylene oxide-modified dipentaerythritol penta(meth)acrylate, and alkylene oxide-modified dipentaerythritol hexa(meth)acrylate.

[0109] An example of a trifunctional (meth)acrylate compound is the following general formula (II), which has a trimethylolpropane backbone: {In the formula, n １ , n ２ , and n ３ Each of these is an integer between 1 and 25, where n is independent. １ +n ２ +n ３ is an integer between 3 and 75, and R １ , R ２ , and R ３ Each of these is independently either a methyl group or a hydrogen atom. Examples of compounds represented by} include:

[0110] Furthermore, an example of a trifunctional (meth)acrylate compound is the following general formula (III), which has glycerin as its backbone: Examples of compounds represented by the formula {wherein Y independently represents an alkylene group, R independently represents a methyl group or a hydrogen atom, and n independently represents an integer from 0 to 200} include:

[0111] An example of a tetrafunctional (meth)acrylate compound is one with a pentaerythritol backbone, as shown in the general formula (IV): {In the formula, n １ , n ２ , n ３ , and n ４ Each of these independently represents an integer from 1 to 25, and n １ +n ２ +n ３ +n ４ is an integer between 4 and 100, and R １ , R ２ , R ３ , and R ４ Each of these independently represents a methyl group or a hydrogen atom, R ５ , R ６ , R ７ , and R ８ Each of these independently represents an alkylene group, R ５ , R ６ , R ７ , and R ８ If there are multiple instances of each, then the multiple R５ , R ６ , R ７ , and R ８ Compounds represented by} may be identical or different from each other.

[0112] An example of a hexafunctional (meth)acrylate compound is the following general formula (V), which has dipentaerythritol as its backbone: Examples of compounds represented by {wherein R independently represents a methyl group or a hydrogen atom, and n independently represents an integer from 0 to 30} include compounds represented by the formula (V). In general formula (V), n may be 0, that is, the ethylene oxide moiety may not be present.

[0113] An example of a (meth)acrylate compound with three or more functions is a compound with a polyglycerin backbone, as shown in the general formula (VI): {In the formula, k, l, and m are each an integer between 0 and 30, and n is an integer between 2 and 20, R １ , R ２ , and R ３ Each of these independently represents a hydrogen atom or a methyl group, R ４ , R ５ , and R ６ Each of these is an alkylene group having 1 to 10 carbon atoms, as shown in formula (VII): [In the formula, R ７ and R ８ Each of these is an alkylene group having 1 to 10 carbon atoms. The group represented by ] and the following formula (VIII): [In the formula, R ９ It is an alkylene group having 1 to 10 carbon atoms. It is one selected from the group consisting of groups represented by ].

[0114] Examples of (B) components with three or more functionalities that can be specifically used include: tetra(meth)acrylate obtained by adding an average of 4 moles of ethylene oxide to pentaerythritol; tetra(meth)acrylate obtained by adding an average of 9 moles of ethylene oxide to pentaerythritol; tetra(meth)acrylate obtained by adding an average of 15 moles of ethylene oxide to pentaerythritol; hexa(meth)acrylate of polyethylene glycol obtained by adding 6 moles of ethylene oxide to dipentaerythritol; hexa(meth)acrylate of polyethylene glycol obtained by adding 13 moles of ethylene oxide to dipentaerythritol; hexa(meth)acrylate of polyethylene glycol obtained by adding 21 moles of ethylene oxide to dipentaerythritol; tetra(meth)acrylate obtained by adding an average of 9 moles of ethylene oxide to diglycerin; penta(meth)acrylate obtained by adding an average of 15 moles of ethylene oxide to triglycerin; Examples include hexa(meth)acrylates obtained by adding an average of 21 moles of ethylene oxide to tetraglycerin; and so on. In the above bifunctional (meth)acrylate compounds, the average number of moles of ethylene oxide and propylene oxide indicates the number of moles per mole of compound. The abbreviations "EO" and "PO" stand for ethylene oxide and propionate oxide, respectively.

[0115] From the viewpoint of adhesion and resolution, component (B) preferably contains a photopolymerizable compound containing an aromatic ring. The content of the photopolymerizable compound containing the aromatic ring is preferably 60% by mass or more, more preferably 70% or more, particularly preferably 80% or more, and most preferably 90% or more, based on the total amount of component (B).

[0116] Examples of photopolymerizable compounds containing aromatic rings include alkylene oxide-modified bisphenol A type di(meth)acrylate represented by general formula (1) and alkylene oxide-modified fluorene type di(meth)acrylate, but it is preferable to contain alkylene oxide-modified bisphenol A type di(meth)acrylate in the above proportion.

[0117] (B) The content of component (B) is preferably 20% by mass or more, more preferably 30% by mass or more, and more preferably 80% by mass or less, and more preferably 70% by mass or less, relative to the solid content of the photosensitive resin composition, from the viewpoint of excellent sensitivity and conformability.

[0118] <Component (C): Photopolymerization Initiator> Component (C) is a photopolymerization initiator. The photopolymerization initiator generates radicals in response to active light emitted from the exposure light source, thereby promoting the polymerization of compounds having ethylenically unsaturated bonds.

[0119] The content of component (C) is 5.0 parts by mass or more per 100 parts by mass of the total amount of components (A) and (B). This makes it easier to obtain sufficient sensitivity, allowing light to penetrate sufficiently to the bottom of the photosensitive resin layer even with a small amount of exposure, and consequently making it easier to achieve good resolution and adhesion. From a similar viewpoint, the content of component (C) is preferably 5.0% by mass or more, more preferably 5.5% by mass or more, even more preferably 6.0% by mass or more, particularly preferably 7.0% by mass or more, more preferably 8.0% by mass or more, and most preferably 9.0% by mass or more, based on the solid content of the photosensitive resin composition. The content of component (C) may be 30% by mass or less, 20% by mass or less, or 15% by mass or less, based on the solid content of the photosensitive resin composition.

[0120] Examples of component (C) include biimidazole compounds, N-aryl-α-amino acid compounds, quinone compounds, aromatic ketone compounds, acetophenone compounds, acylphosphine oxide compounds, benzoin compounds, benzoin ether compounds, dialkylketal compounds, thioxanthone compounds, dialkylaminobenzoic acid ester compounds, oxime ester compounds, and acridine compounds, as well as pyrazoline derivatives, and ester compounds of N-aryl amino acids, and halogen compounds.

[0121] Examples of biimidazole compounds include compounds having a biimidazole structure, such as rophine dimers, i.e., dimers of 2,4,5-triarylimidazole.

[0122] Dimers of 2,4,5-triarylimidazole include the dimer of 2-(o-chlorophenyl)-4,5-diphenylbiimidazole (also known as 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole), the dimer of 2-(o-chlorophenyl)-4,5-bis-(m-methoxyphenyl)imidazole, the dimer of 2-(p-methoxyphenyl)-4,5-diphenylimidazole, and 2,2',5-tris-(o-chlorophenyl)-4-(3,4-dimethoxyphenyl)-4',5'-diphenyl Nylbiimidazole, 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-methylphenyl) Toxyphenyl)-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,Examples include 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.

[0123] From the viewpoint of high sensitivity, resolution, and adhesion, it is preferable that component (C) contains a rofin dimer, and more preferably a dimer of 2-(o-chlorophenyl)-4,5-diphenylimidazole.

[0124] When component (C) contains a biimidazole compound, the content of the biimidazole compound may be 4.5% by mass or more, preferably 5.0% by mass or more, more preferably 5.3% by mass or more, even more preferably 5.5% by mass or more, even more preferably 6.0% by mass or more, particularly preferably 7.0% by mass or more, even more preferably 8.0% by mass or more, and most preferably 9.0% by mass or more, based on the solid content of the photosensitive resin composition. When component (C) contains a biimidazole compound, the content of the biimidazole compound may be 15.0% by mass or less from the viewpoint of solubility. Also, when component (C) contains a biimidazole compound, the content of the biimidazole compound is preferably 5.0 parts by mass or more, more preferably 5.5 parts by mass or more, and even more preferably 6.0 parts by mass or more, based on 100 parts by mass of the total amount of components (A) and (B). The preferred lower limit for component (C) relative to 100 parts by mass of the total amount of components (A) and (B) described above, and the upper limit for component (C) relative to 100 parts by mass of the total amount of components (A) and (B), which can be optionally combined, are, when a biimidazole compound is included, the content of the biimidazole compound may be, for example, 15.0 parts by mass or less, 12.0 parts by mass or less, or 10.0 parts by mass or less. The preferred content of the biimidazole compound is the same when component (C) contains a dimer of 2,4,5-triarylimidazole as the biimidazole compound.

[0125] Examples of N-aryl-α-amino acid compounds include N-phenylglycine, N-methyl-N-phenylglycine, and N-ethyl-N-phenylglycine. Among these, N-phenylglycine is preferred due to its high sensitizing effect.

[0126] Examples of quinone compounds include 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthaquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, and 3-chloro-2-methylanthraquinone.

[0127] Examples of aromatic ketone compounds include benzophenone.

[0128] Examples of acetophenone compounds include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-(4-dodecylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)-phenyl(2-hydroxy-2-propyl)ketone, 1-hydroxycyclohexylphenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propanone-1. Examples of commercially available acetophenone compounds include the Irgacure series (manufactured by Ciba Specialty Chemicals: Irgacure-907, Irgacure-369, and Irgacure-379, etc.).

[0129] Examples of acylphosphine oxide compounds include 2,4,6-trimethylbenzyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide. Examples of commercially available acylphosphine oxide compounds include Lucilin TPO (manufactured by BASF) and Irgacure-819 (manufactured by Ciba Specialty Chemicals).

[0130] Examples of benzoin compounds and benzoin ether compounds include benzoin, benzoin ethyl ether, benzoin phenyl ether, methylbenzoin, and ethylbenzoin.

[0131] Examples of dialkylketal compounds include benzyldimethylketal and benzyldiethylketal. Examples of thioxanthone compounds include 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorthioxanthone. Examples of dialkylaminobenzoic acid ester compounds include ethyl dimethylaminobenzoate, ethyl diethylaminobenzoate, ethyl-p-dimethylaminobenzoate, and 2-ethylhexyl-4-(dimethylamino)benzoate.

[0132] Examples of oxime ester compounds include 1-phenyl-1,2-propanedione-2-O-benzoyl oxime and 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl) oxime. Examples of commercially available oxime ester compounds include CGI-325, Irgacure-OXE01, and Irgacure-OXE02 (all manufactured by Ciba Specialty Chemicals).

[0133] As for the acridine compound, 1,7-bis(9,9'-acridinyl)heptane or 9-phenylacridine are preferred in terms of sensitivity, resolution, and availability.

[0134] Examples of ester compounds of N-aryl amino acids include methyl ester of N-phenylglycine, ethyl ester of N-phenylglycine, n-propyl ester of N-phenylglycine, isopropyl ester of N-phenylglycine, 1-butyl ester of N-phenylglycine, 2-butyl ester of N-phenylglycine, tert-butyl ester of N-phenylglycine, pentyl ester of N-phenylglycine, hexyl ester of N-phenylglycine, pentyl ester of N-phenylglycine, and octyl ester of N-phenylglycine.

[0135] Examples of halogen compounds include amyl bromide, isoamyl bromide, isobutylene bromide, ethylene bromide, diphenylmethyl bromide, benzyl bromide, methylene bromide, tribromomethylphenylsulfone, carbon tetrabromide, tris(2,3-dibromopropyl)phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, chlorinated triazine compounds, and diallylodonium compounds. Among these, tribromomethylphenylsulfone is preferred.

[0136] <Component (D): Polymerization Inhibitor> The photosensitive resin composition or photosensitive resin layer may optionally contain a polymerization inhibitor as component (D). In this disclosure, the inclusion of a polymerization inhibitor tends to improve the transparency and resolution between resist patterns, as the polymerization inhibitor present near the exposed and unexposed areas suppresses the reaction in the unexposed areas.

[0137] (D) Examples of components include phenothiazine, p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, gallic acid, 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), triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], nitrosophenylhydroxyamine aluminum salt (for example, an aluminum salt to which 3 moles of nitrosophenylhydroxylamine have been added), diphenylnitrosamine, etc. In particular, from the viewpoint of further improving transparency and resolution, phenothiazine, tert-butylcatechol, gallic acid, or nitrosophenylhydroxyamine aluminum salt are preferred, compounds having two or more phenolic hydroxyl groups are more preferred, and tert-butylcatechol or gallic acid are even more preferred. These can be used individually or in combination of two or more.

[0138] The content of component (D) is preferably 0.025 parts by mass or more per 100 parts by mass of the total amount of components (A) and (B). Increasing the content of component (D) to 0.025 parts by mass or more per 100 parts by mass of the total amount of components (A) and (B) tends to improve the resolution of fine patterns, and this tendency is particularly pronounced when component (D) is a compound having two or more phenolic hydroxyl groups. The content of a compound having two or more phenolic hydroxyl groups is preferably 0.025 parts by mass or more per 100 parts by mass of the total amount of components (A) and (B), more preferably 0.050 parts by mass or more, particularly preferably 0.075 parts by mass or more, and most preferably 0.080 parts by mass or more. The upper limit of the content of component (D) is not particularly limited, but for example, it may be 0.150 parts by mass or less, 0.120 parts by mass or less, or 0.090 parts by mass or less, per 100 parts by mass of the total amount of components (A) and (B).

[0139] <Component (E): Hydrogen Donor> The photosensitive resin composition or photosensitive resin layer may optionally contain a hydrogen donor as component (E). While this disclosure does not wish to be bound by theory, it has been found that the combined use of component (C) and component (E) is involved in the hydrogen abstraction reaction from the hydrogen donor by the radical of the photopolymerization initiator, and that improvements in sensitivity and crosslinking density can be expected by controlling the reaction rate.

[0140] (E) The component is not particularly limited, but for example, leucocrystal violet may be used.

[0141] The mass ratio of the content of component (E) to the content of component (C) (i.e., mass of hydrogen donor (E) / mass of photopolymerization initiator (C)) is preferably 0.07 or higher, more preferably 0.09 or higher, and even more preferably 0.13 or higher, from the viewpoint of improving sensitivity and crosslinking density. The effect of the photosensitive resin laminate of this disclosure is not intended to be constrained by theory, but as described above, it is thought to be due to increasing the rate of hydrogen abstraction reaction from the hydrogen donor by radicals of the photopolymerization initiator. Therefore, increasing the amount of hydrogen donor increases the initial concentration of the reaction, improves reactivity, and consequently improves sensitivity and crosslinking density. Accordingly, it was found that the degree of improvement in effect correlates more with controlling the above mass ratio (mass of hydrogen donor (E) / mass of photopolymerization initiator (C)) than with controlling the content of component (E) alone.

[0142] <Other Ingredients> The photosensitive resin composition may optionally contain other ingredients (base dyes, sensitizers, antioxidants, stabilizers, plasticizers, etc.).

[0143] Examples of base dyes include Basic Green 1 [CAS number (same below): 633-03-4] (e.g., Aizen Diamond Green GH, product name, manufactured by Hodogaya Chemical Co., Ltd.), Malachite Green [CAS number 569-64-2], Tris(4-dimethylamino-2-methylphenyl)methane [Leucomalachite Green], Fuchsine [632-99-5], Methyl Violet [603-47-4], Methyl Green [82-94-0], Victoria Blue B [2580-56-5], Basic Blue 7 [2390-60-5] (e.g., Aizen Victoria Pure Blue) Examples include 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 these, Basic Green 1 is preferred from the viewpoint of improving colorability, hue stability, and exposure contrast. These can be used individually or in combination of two or more.

[0144] The base dye content is preferably 0.001 to 2.0% by mass, more preferably 0.005 to 0.5% by mass, and even more preferably 0.01 to 0.1% by mass. From the viewpoint of obtaining good colorability, the base dye content is preferably above the lower limit, while from the viewpoint of maintaining the sensitivity of the photosensitive layer, it is preferably below the upper limit.

[0145] As a sensitizer, sensitizing compounds other than the above-mentioned component (C) may be used, such as anthracene compounds, thioxanthone compounds, dialkylaminobenzoic acid ester compounds, dialkylaminobenzophenones, pyrazoline derivatives, and coumarin derivatives. Among these, it is preferable to include at least one selected from the group consisting of anthracene compounds and coumarin derivatives.

[0146] Examples of anthracene compounds include anthracene and anthracene derivatives, of which anthracene derivatives include, for example, 9,10-dialkoxyanthracene, 9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, 9,10-dibutoxyanthracene, 9,10-diphenylanthracene, 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, and 10-phenyl-9-anthraceneboronic acid. Among these, 9,10-dibutoxyanthracene, 9,10-diphenylanthracene, and 10-phenyl-9-anthraceneboronic acid are preferred from the viewpoint of sensitizing effect.

[0147] The coumarin derivative can be any compound having a coumarin skeleton, such as 2,3,6,7-tetrahydro-9-methyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinoridine-11-one (also known as "coumarin 102").

[0148] Examples of dialkylaminobenzophenone compounds include Michla's ketone [4,4'-bis(dimethylamino)benzophenone] and 4-methoxy-4'-dimethylaminobenzophenone. As for aromatic ketone compounds, 4,4'-bis(diethylamino)benzophenone can also be mentioned from the viewpoint of sensitizing effect and adhesion.

[0149] As pyrazoline derivatives, 1-phenyl-3-(4-tert-butyl-styryl)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-phenyl-3-(4-biphenyl)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-phenyl-3-(4-biphenyl)-5-(4-tert-octyl-phenyl)-pyrazoline, and 1-phenyl-3-(4-methoxystyryl)-5-(4-methoxyphenyl)-pyrazoline are preferred from the viewpoint of adhesion and rectangularity of the resist pattern.

[0150] From the viewpoint of sensitivity, the sensitizer content is preferably 0.050 to 2.00% by mass, more preferably 0.10 to 1.50% by mass, and even more preferably 0.20 to 1.00% by mass, relative to the solid content of the photosensitive resin composition.

[0151] Examples of antioxidants include triphenyl phosphite (e.g., manufactured by ADEKA, trade name: TPP), tris(2,4-di-tert-butylphenyl) phosphite (e.g., manufactured by ADEKA, trade name: 2112), tris(mononylphenyl) phosphite (e.g., manufactured by ADEKA, trade name: 1178), and bis(mononylphenyl)-dinonylphenyl phosphite (e.g., manufactured by ADEKA, trade name: 329K). These can be used individually or in combination of two or more.

[0152] The antioxidant content is preferably 0.01 to 0.8% by mass, and more preferably 0.01 to 0.3% by mass, relative to the total solid content mass of the photosensitive resin composition. From the viewpoint of exhibiting good hue stability of the resist pattern and improving the sensitivity of the photosensitive layer, the antioxidant content is preferably above the lower limit. On the other hand, from the viewpoint of exhibiting good hue stability while suppressing the color development of the resist pattern and improving adhesion, it is preferably below the upper limit.

[0153] Stabilizers can be used to improve the thermal stability of the photosensitive resin composition. Examples of stabilizers include at least one alkylene oxide compound having a glycidyl group and a benzotriazole compound. These can be used individually or in combination of two or more.

[0154] Examples of plasticizers include glycol esters such as polyethylene glycol, polypropylene glycol, polyoxypropylene polyoxyethylene ether, polyoxyethylene monomethyl ether, polyoxypropylene monomethyl ether, polyoxyethylene polyoxypropylene monomethyl ether, polyoxyethylene monoethyl ether, polyoxyethylene monoethyl ether, polyoxyethylene polyoxypropylene monoethyl ether; phthalate esters of diethyl phthalate; o-toluenesulfonamide, p-toluenesulfonamide, tributyl citrate, triethyl citrate, triethyl acetyl citrate, tri-n-propyl acetyl citrate, tri-n-butyl acetyl citrate, etc.

[0155] The plasticizer content is preferably 1 to 50% by mass, and more preferably 1 to 30% by mass, relative to the solid content of the photosensitive resin composition. When this percentage is 1% by mass or more, it is easier to suppress delays in development time and to impart flexibility to the cured film. When this percentage is 50% by mass or less, it tends to suppress insufficient curing and edge fusing.

[0156] (Solvent) The photosensitive resin layer is formed by applying a coating solution, in which the photosensitive resin composition is dispersed in a solvent, to a temporary support or to any intermediate layer applied to the temporary support, and then drying it. The resulting photosensitive resin layer may contain residual solvent.

[0157] Examples of solvents include ketones, such as methyl ethyl ketone; alcohols, such as methanol, ethanol, and isopropanol; and toluene. Acetone is also an example of a solvent. The solvent content remaining in the photosensitive resin layer is preferably 5.0% by mass or less, and more preferably 3.0% by mass or less, relative to the solid content of the photosensitive resin composition.

[0158] A further aspect of the present disclosure is a method for producing a photosensitive resin laminate. Such a method may include, for example, the following steps: applying a photosensitive resin composition containing the above-mentioned components and adjusted so that the content of component (C) is 5.0 parts by mass or more per 100 parts by mass of the total amount of components (A) and (B) onto a temporary support to form a coating film; and drying the coating film to obtain a photosensitive resin layer.

[0159] The process of forming a coating film may include the following steps: a step of obtaining a coating solution by dissolving a photosensitive resin composition in a solvent, and a step of applying the coating solution to a temporary support. The coating solution can be prepared by mixing a photosensitive resin composition with a solvent that dissolves the composition. Examples of solvents include ketones such as acetone and methyl ethyl ketone; alcohols such as methanol, ethanol, and isopropyl alcohol; and so on. The photosensitive resin composition and solvent may be mixed so that the viscosity of the coating solution is 500 to 4000 mPa·sec at 25°C.

[0160] A known method can be used to apply the coating liquid to the temporary support, for example, by using a bar coater or a roll coater. A coating film is obtained by applying the coating liquid to the temporary support. Drying of the coating film can be carried out using a known dryer and under known conditions (drying temperature and drying time).

[0161] Furthermore, the preferred details (composition, content, various ratios, etc.) described in the section on photosensitive resin laminates above may also be applied to the method for manufacturing photosensitive resin laminates.

[0162] The average thickness of the photosensitive resin layer can be measured using a Fujiwork FT-A series contact-type continuous thickness gauge, a Mitutoyo VL-50 series dot-type thickness gauge, or a Hutech AccureX series non-contact inline thickness gauge. The average thickness of the photosensitive resin layer can be calculated by measuring the total thickness of the photosensitive resin laminate and taking the difference between that thickness and the thickness of other parts of the photosensitive resin laminate, such as support films and protective films. In this case, it is preferable to measure the thickness at 10 or more points in the width direction of the photosensitive resin laminate and use the average value as the average thickness of the photosensitive resin layer.

[0163] <Photosensitive Element> The photosensitive element of this disclosure has a laminated structure in which a support film, an intermediate layer, and the photosensitive resin layer described above are sequentially laminated. The photosensitive element may optionally include a protective film.

[0164] The photosensitive element, having an intermediate layer in its laminated structure, allows for exposure after the support film has been removed, and also reduces rattle of the resist pattern's sidewalls caused by scratches or foreign matter on the support film. Furthermore, by having an intermediate layer, the photosensitive element can impart any desired functionality, such as oxygen barrier properties, to the intermediate layer, and consequently, these functionalities can be maintained even after the support film has been removed.

[0165] The laminated structure of the photosensitive element can be formed by placing an intermediate layer between a temporary support and a photosensitive resin layer in the photosensitive resin laminate described above; or by peeling the temporary support from the photosensitive resin laminate described above to remove the photosensitive resin layer, and then sequentially laminating the support film, the intermediate layer, and the photosensitive resin layer. The placement or lamination of the intermediate layer can be carried out by coating the resin composition constituting the intermediate layer onto the support or film.

[0166] As described above, the intermediate layer is preferably an oxygen barrier layer and / or a water-soluble resin layer, and more preferably a water-soluble resin layer, from the viewpoint of ensuring exposure performance and functionality even after the support film has been peeled off from the photosensitive element.

[0167] The water-soluble resin layer as an intermediate layer is given by the following general formula (I): {In the formula, R １ and R ２ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and A is -CH ２ CH ２ O-unit and / or -CH ２ CH (CH ３ It is preferable to include a compound represented by the formula (I) which contains one or more single or repeating structures including an O-unit. By including the compound represented by the above general formula (I) in the water-soluble resin, the tackiness of the intermediate layer can be reduced and the bleeding of the compound itself can be suppressed.

[0168] The water-soluble resin layer, which serves as an intermediate layer, preferably contains polyvinyl alcohol (PVA). Including PVA in the water-soluble resin constituting the water-soluble resin layer can improve oxygen barrier properties. It is more preferable that the water-soluble resin layer contains 50% to 100% by mass of PVA, based on the mass of the water-soluble resin layer. Including 50% or more by mass of PVA in the water-soluble resin layer can further improve oxygen barrier properties.

[0169] The thickness of the water-soluble resin layer as an intermediate layer is preferably 1 μm to 8 μm. By making the thickness of the water-soluble resin layer 1 μm or more, the stability of the water-soluble resin layer can be ensured after peeling off the support film such as PET film. On the other hand, by making the thickness of the water-soluble resin layer 8 μm or less, developability can be ensured.

[0170] Furthermore, the photosensitive element may be in the form of a long length, or it may be in the form of a roll in which a long length of photosensitive element is wound around a core.

[0171] The support film for the photosensitive element may have the same configuration as the temporary support for the photosensitive resin laminate described above, and / or the protective film for the photosensitive element may have the same configuration as the protective layer for the photosensitive resin laminate described above. Therefore, the preferred details (composition, content, various ratios, etc.) described in the section on the photosensitive resin laminate may also be applied to the photosensitive element and its roll.

[0172] The support film for the photosensitive element is preferably a biaxially oriented polyester film containing a fine particle-containing resin layer on at least the side opposite to the side where the intermediate layer is laminated, and it is also preferable that fine particles are present on both sides. The fine particles in the fine particle-containing resin layer may be, for example, a lubricant. Among support films such as PET, it is preferable to have a lubricant on the uncoated surface where the intermediate layer is not arranged, as this ensures the transportability of the photosensitive element.

[0173] It is preferable that the surface roughness (Rz1) of the surface on which the intermediate layer of the support film is laminated of the photosensitive element is smaller than the surface roughness (Rz2) of the surface on the opposite side of the support film from which the intermediate layer is laminated. It is preferable to make the surface roughness (Rz) of the coated surface of the support film on which the intermediate layer is arranged by coating relatively smaller, as this smooths the contact surface between the intermediate layer, which is made of PVA or the like, and the support film (e.g., PET film), thereby reducing patterning defects.

[0174] 《Method for Forming a Resist Pattern》 A further aspect of the present disclosure is a method for forming a resist pattern using the above-mentioned photosensitive resin laminate or photosensitive element. Such a method includes the following steps: a step of laminating the photosensitive resin layer of the above-mentioned photosensitive resin laminate or photosensitive element onto a substrate (lamination step); a step of exposing the photosensitive resin layer laminated on the substrate (exposure step); and a step of removing the unexposed portion of the photosensitive resin layer using an alkaline aqueous solution (development step). A resist pattern is formed by going through these steps.

[0175] [Lamination Process] In the lamination process, the photosensitive resin layer of the photosensitive resin laminate is laminated onto the substrate. Specifically, the lamination process includes: a step of exposing the photosensitive resin laminate by peeling off the protective layer from the photosensitive resin laminate or peeling off the protective film from the photosensitive element; and a step of laminating the photosensitive resin layer onto the substrate so that the exposed photosensitive resin laminate is in contact with the substrate. In the lamination process, a predetermined laminator device may be used, in which case the photosensitive resin layer may be heat-pressed onto the surface of the substrate.

[0176] Examples of substrate materials include metals and / or insulators, such as copper, stainless steel (SUS), glass, and indium tin oxide (ITO). The heating temperature during lamination is, for example, 40°C to 160°C. Heat bonding can be performed by using a laminator device equipped with rolls, or by repeatedly passing the laminate of the substrate and photosensitive resin layer through the rolls several times. Heat bonding may be performed under reduced pressure if desired. When laminating the photosensitive resin laminate onto the substrate, the laminated surface on the substrate may be smoothed as needed. From the viewpoint of optimizing the exposure process after peeling off the temporary support or support film, the substrate is preferably a metal plate or a metal-coated insulator.

[0177] [Exposure Process] In the exposure process, the photosensitive resin layer laminated on the substrate is exposed. Specifically, in the exposure process, the photosensitive resin layer is exposed using an exposure machine. Exposure can be performed before peeling off the temporary support from the photosensitive resin laminate or before peeling off the support film from the photosensitive element, or it can be performed after peeling off the temporary support or support film. In the exposure process, when exposure is performed via a photomask, the exposure amount may be determined by the illuminance of the light source and the exposure time, or it may be measured using a light meter.

[0178] In the exposure process, direct imaging exposure may be performed. In direct imaging exposure, the photosensitive resin layer is exposed by a direct writing device without using a photomask. As the light source at this time, a semiconductor laser or an ultra-high pressure mercury lamp with a wavelength of 350 to 410 nm is used. If the writing pattern is controlled by a computer, the exposure amount may be determined by the illuminance of the exposure light source and the moving speed of the substrate.

[0179] In the exposure process, the method of irradiating with exposure light is preferably at least one method selected from projection exposure, proximity exposure, contact exposure, direct imaging exposure, and electron beam direct writing, with projection exposure or direct imaging exposure being more preferred.

[0180] The exposure process may include a step of heating the substrate and the photosensitive resin layer after exposure (post-exposure heating step) after the exposure and before the development step. In this heating step, the heating temperature is preferably about 30 to about 200°C, more preferably 30 to 150°C, and even more preferably 35 to 120°C. Performing the heating step makes it easier to achieve excellent resolution and adhesion. Heating may be performed using an infrared or far-infrared heating furnace, hot air, a constant temperature bath, a hot plate, a hot air dryer, an infrared dryer, and a hot roll, etc.

[0181] The elapsed time from the exposure process to the heating process, or more precisely, the time from when exposure is completed (i.e., when exposure is stopped) to when heating begins, is preferably 10 to 600 seconds, and more preferably 20 to 300 seconds. The time from when heating begins to when heating is stopped is preferably 1 to 120 seconds, and more preferably 5 to 60 seconds.

[0182] [Development Process] In the development process, the unexposed areas of the photosensitive resin layer are removed using an alkaline aqueous solution. This yields a resist pattern. If a temporary support layer or support film is laminated on the photosensitive resin layer, the development process may be performed after removing this temporary support layer or support film.

[0183] As for alkaline aqueous solutions in developing solutions, Na ２ CO ３ _K ２ CO ３ Aqueous solutions of , and tetramethylammonium hydroxide are preferred. The alkaline aqueous solution is selected according to the properties of the photosensitive resin layer, for example, a concentration of 0.2 to 2% by mass of Na ２ CO ３ An aqueous solution is used. The developer may contain a surfactant and / or an antifoaming agent, and may also contain a small amount of organic solvent to accelerate development. In the development process, it is preferable to keep the temperature of the developer constant within the range of 20°C to 40°C.

[0184] The development process preferably includes a step of washing the substrate and resist pattern with water after development (water washing step). The water washing step makes it easier to remove any developer remaining on the substrate and resist pattern. Examples of water used for washing in the water washing step include pure water and industrial water. From the viewpoint of excellent resolution and ease of forming a highly rectangular resist pattern, a polyvalent metal salt at a concentration of 0.001 to 1% by mass may be mixed into the water for washing, according to the characteristics of the photosensitive resin layer. Examples of polyvalent metal salts include MgSO4. ４ These are some examples. In the washing process, it is preferable to keep the temperature of the washing water constant within the range of 20°C to 40°C.

[0185] The developing process may include a step of heating the substrate and the formed resist pattern (post-developing heating step) after the above-mentioned developing, or after the above-mentioned developing and washing with water. In this heating step, the heating temperature is preferably 60°C to 300°C. Performing this heating step makes it easier to improve the chemical resistance of the resist pattern. Heating may be carried out using an infrared or far-infrared heating furnace, or by hot air, etc.

[0186] Regarding the order of the steps described above, it is preferable from the viewpoint of optimizing the exposure process after peeling off the support film to perform the following steps: laminating the photosensitive element onto the surface of a metal plate or metal-coated insulator, peeling off the support film from the photosensitive element, exposing it to ultraviolet light, and then removing the unexposed areas by developing.

[0187] 《Method for Manufacturing Conductor Patterns》 A further aspect of the present disclosure is a method for manufacturing a conductor pattern using the above-mentioned photosensitive resin laminate or photosensitive element. Such a method includes, for example, the following steps: a step of obtaining a substrate on which a resist pattern is formed (a step of manufacturing a substrate with a resist pattern); a step of performing an etching or plating treatment on the substrate on which the resist pattern is formed and forming a conductor pattern (a step of forming a conductor pattern); and a step of peeling the resist pattern from the substrate on which the conductor pattern is formed (a peeling step).

[0188] [Process for manufacturing substrates with resist patterns] In the process for manufacturing substrates with resist patterns, a substrate with a resist pattern formed on it is obtained. In this process, the section on "Method for forming resist patterns" above can be referred to, thereby obtaining a substrate with a resist pattern.

[0189] [Conductor Pattern Formation Process] In the conductor pattern formation process, an etching or plating process is performed on the substrate on which the resist pattern has been formed, and then a conductor pattern is formed. Specifically, in the conductor pattern formation process, a conductor pattern is formed on the surface (for example, the copper surface) of the substrate (as described above, for example, a metal plate and a metal film insulating plate) exposed by development, using a known etching method or plating method.

[0190] Etching is performed, for example, by spraying an etching solution onto the resist pattern and the substrate surface. Examples of etching methods include acid etching and alkaline etching. Examples of etching solutions include aqueous hydrochloric acid solution, aqueous ferric chloride solution, or mixtures thereof.

[0191] The plating process is carried out by developing (removing) the exposed substrate portion according to a known plating method, and then applying metal plating (for example, metal plating with copper sulfate plating solution) or solder plating to that portion.

[0192] [Peeling Process] In the peeling process, the resist pattern is peeled off from the substrate on which the conductor pattern is formed. By removing the resist pattern from the substrate, a wiring board (e.g., a printed circuit board) having the desired conductor pattern is obtained.

[0193] In the stripping process, the resist pattern is removed from the substrate using an aqueous solution (stripping solution) that is more alkaline than the developer. Examples of the stripping solution include an aqueous solution of NaOH or KOH with a concentration of 2 to 5% by mass, and an aqueous solution of an organic amine. The stripping solution may contain a small amount of water-soluble solvent. Examples of water-soluble solvents include alcohol. The temperature of the stripping solution in the stripping process is preferably in the range of 40°C to 70°C. The stripping time may be set as appropriate.

[0194] This disclosure is not limited to the embodiments described above, and can be implemented in various ways within the scope of its gist.

[0195] The embodiments of this disclosure will be described below with reference to examples and comparative examples. However, this disclosure is not limited to the following examples. With respect to the examples and comparative examples, various manufacturing, measurement, and evaluation methods were carried out as follows.

[0196] [Preparation of the photosensitive resin composition solution] [Synthesis of component (A-1)] 27 g of methacrylic acid, 49 g of styrene, 20 g of benzyl methacrylate, and 4 g of 2-hydroxyethyl methacrylate (copolymer component) were mixed with 2.0 g of azobisisobutyronitrile to obtain solution (a). A mixture of 200 g of methyl ethyl ketone and 100 g of ethanol was placed in a flask equipped with a stirrer, reflux condenser, thermometer, dropping funnel, and nitrogen gas inlet tube. The mixture was stirred while blowing nitrogen gas into the flask, and the temperature of the mixture in the flask was raised to 80°C. 300 g of solution (a) was added to the mixture in the flask dropwise over 4 hours at a constant dropping rate, and then stirred at 80°C for 2 hours.

[0197] Next, solution (b) was obtained by dissolving 0.5 parts by mass of azobisisobutyronitrile in 50 parts by mass of a mixture of 30 parts by mass of methyl ethyl ketone and 20 parts by mass of ethanol. 50 g of solution (b) was added dropwise to the mixture in the flask over 10 minutes at a constant dropping rate, and then stirred at 80°C for 3 hours. The mixture in the flask was then further heated to 90°C over 30 minutes, and then kept at 90°C for 2 hours. After that, stirring was stopped, and the mixture in the flask was cooled to room temperature (25°C). This yielded (A-1) as an alkali-soluble polymer. By adding the monomers of each copolymer component in the amounts shown in Table 2-1, and adjusting the amount of azobisisobutyronitrile to obtain the desired weight-average molecular weight, solutions containing components (A-2) to (A-9) were obtained by performing the same procedure.

[0198] [Weight-Average Molecular Weight] For each solution, the weight-average molecular weight Mw of component (A) was derived using gel permeation chromatography (GPC) and then converted using a calibration curve for standard polystyrene. The GPC conditions are as follows: (GPC conditions) Pump: JASCO PU-980 Columns: A total of four columns as follows: Shodex KF-807 x 1, KF-806M x 2, KF-802.5 x 1 Eluent: Tetrahydrofuran Measurement temperature: 40°C Flow rate: 2.05 mL / min Detector: JASCO RI-1530

[0199] In Table 2-1, the proportion of constituent units derived from each monomer listed in the component details is a mass proportion, Mw is the weight-average molecular weight, Wa represents the parts by mass of constituent units derived from monomers having aromatic rings when the total solid content of components (A-1) to (A-9) is set to 100 parts by mass, and the acid value and hydroxyl value are values ​​calculated based on the amount of copolymer components used in the preparation of the above-mentioned solution.

[0200] In Table 2-2, the amounts of ethylene oxide and propylene oxide added are listed as the amount added per mole of the compound.

[0201] A coating solution (a prepared solution for a photosensitive resin composition) was obtained by stirring and mixing the components shown in Table 3 (the numbers for each component indicate the amount of solids (parts by mass)) with ethanol measured to a solid content concentration of 40%, so that the amount of each component as solids was as shown in Table 3.

[0202] [Examples 1-34, 36-38, and Comparative Examples 1-2: Preparation of Photosensitive Resin Laminates] A 16 μm thick polyethylene terephthalate film (Toray Industries, Ltd. "16FS30") was used as the support film. A photosensitive resin layer was applied to its surface using a bar coater to a thickness of 7 μm, and then dried in a 95°C dryer for 1.5 minutes. This formed a photosensitive resin layer on the support film, obtaining a photosensitive resin laminate. In this example, a photosensitive resin laminate was used in which a protective film, a 18 μm thick biaxially oriented polypropylene film (Oji F-Tex Co., Ltd., product name "E-200C3"), was laminated on the side opposite the support film of the photosensitive resin layer.

[0203] [Example 35: Preparation of a photosensitive resin laminate with an intermediate layer] The same procedure as in Example 1 was followed, except that a 3 μm intermediate layer was formed on a support film using the method described below, and then a photosensitive resin layer was applied. The result was treated as a photosensitive resin laminate. The intermediate layer was formed using the following procedure.

[0204] 70 parts by mass of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name: PVA-205), 25 parts by mass of polyvinylpyrrolidone (manufactured by Nippon Shokubai Co., Ltd., K-30), and 5 parts by mass of polyalkylene glycol (manufactured by ADEKA, ADEKA Pluronic® L-44) were slowly added to 500 parts by mass of water and 250 parts by mass of 1-propanol at room temperature and mixed. The mixture was heated to 90°C and stirred for 1 hour, then cooled to room temperature to obtain a resin composition for forming an intermediate layer. Next, the resin composition for forming an intermediate layer was applied to a support film (Toray Industries, Inc., "16FS30") using a bar coater to ensure uniform thickness, and dried in a 95°C dryer for 10 minutes to form an intermediate layer with a thickness of 3 μm.

[0205] [Formation of resist pattern] <Surface preparation of substrate> A copper-clad laminate with a total thickness of 0.4 mm was prepared by laminating rolled copper foil with a thickness of 18 μm. Then, this surface was treated with 10 mass% H ２ SO ４ The copper-clad laminate was washed with an aqueous solution, and then with pure water. After washing, the copper-clad laminate was preheated to 50°C.

[0206] <Lamination> While peeling off the protective film from the photosensitive resin laminate, the copper-clad laminate, preheated to 50°C, was laminated using a hot roll laminator (Taisei Laminator Co., Ltd., VA-700SH) at a roll temperature of 105°C so that the photosensitive resin layer was in contact with the surface of the copper-clad laminate. This obtained an evaluation substrate. The air pressure during lamination was set to 0.35 MPa and the lamination speed was set to 1.5 m / min.

[0207] <Exposure: Direct Writing> In Examples 1 to 38 and Comparative Examples 1 to 2, substrates that had been laminated for 2 hours were directly exposed using a direct writing exposure machine (SDi, manufactured by Oak Manufacturing Co., Ltd., wavelength 402 nm) with a predetermined direct imaging (DI) exposure pattern. Exposure was performed at the optimal exposure dose (the exposure dose at which the maximum number of remaining film stages after exposure using a 41-step step tablet as a mask and subsequent development was 15 stages). In Example 35, the same exposure was performed after peeling off the support film from the substrate that had been laminated for 2 hours.

[0208] <Exposure: Projection Exposure> In Examples 24 to 32, substrates that had been laminated for 2 hours were exposed at a wavelength of 365 nm using a projection exposure machine (UX-23101 manufactured by Ushio Inc.) with a predetermined exposure mask pattern. Exposure was performed at the optimal exposure dose (the exposure dose at which the maximum number of remaining film steps after exposure using a 41-step step tablet as a mask and subsequent development was 15 steps).

[0209] <Heating> Two minutes after exposure, the substrate was heated for 30 seconds in a forced-air constant-temperature incubator (Yamato Scientific Co., Ltd., DKM600) set to 70°C.

[0210] <Developing> The support film was peeled off from the substrates other than those in Example 35. Then, using an alkaline developer (Fuji Kiko Co., Ltd., dry film developer), 1% by mass Na was used at 30°C. ２ CO ３ An aqueous solution was sprayed onto the photosensitive resin layer for a predetermined period of time, thereby performing development. The spraying time was set to twice the minimum development time, and the washing time after development (water rinsing by spraying) was also set to twice the minimum development time. In this case, the shortest time required for the unexposed portion of the photosensitive resin layer to completely dissolve was treated as the minimum development time. From the above, a substrate with a resist pattern (evaluation substrate) was obtained.

[0211] [Evaluation and Measurement] [Absorbance at 365 nm (unit: 1 / μm), absorbance at 402 nm (unit: 1 / μm)] After peeling off the protective film of the photosensitive resin laminate, the absorbance of the photosensitive resin layer at wavelengths of 365 and 402 nm was measured using a U-3010 spectrophotometer (manufactured by Hitachi High-Technologies Corporation) with a 16 μm thick polyethylene terephthalate film (support film, Toray Industries, Inc. "16FS30") as a reference. By dividing the measured absorbance by the thickness of the photosensitive resin layer, the absorbance at 365 nm per 1 μm of thickness of the photosensitive resin layer (unit: 1 / μm) and the absorbance at 402 nm per 1 μm of thickness of the photosensitive resin layer (unit: 1 / μm) were derived. The measurement was performed with a slit of 4 nm and a scan speed of 600 nm / min.

[0212] [Image Quality (including Resolution)] Evaluation was performed using a drawing pattern or exposure mask pattern with a line width (L) / space width (S) of x / x {x = 0.5 to 3.0 (varying at 0.1 μm intervals)} (unit: μm). That is, a resist pattern was formed by exposure with the optimal exposure amount, followed by the heating and developing processes described above.

[0213] Figure 1 is a plan view showing an example of a drawing pattern configuration. In the figure, in the drawing area 100, the exposed area is indicated by reference numeral 10, and the unexposed area (shaded area) is indicated by reference numeral 1. The unexposed area 1 has a predetermined width and extends in the X direction, and multiple such unexposed areas 1 are arranged in the width direction (Y direction) at predetermined intervals. Theoretically, by exposing the photosensitive resin layer based on the drawing pattern in Figure 1, it is expected that a resist pattern with L / S corresponding to the width of the unexposed area 1 (S: space) and the width of the exposed area 10 (L: line) will be formed.

[0214] When the obtained resist pattern was observed with an optical microscope at 100x magnification, the minimum line width x at which the line portions (exposed areas) did not meander or break, and the space portions (unexposed areas) were removed without residue, was defined as the "resolution (unit: μm)". A smaller value indicates better resolution. The observed patterns were judged according to the following criteria: ◎ (Excellent): 1.3 μm or less ○ (Good): Greater than 1.3 μm and 1.7 μm or less △ (Acceptable): Greater than 1.7 μm and 2.0 μm or less × (Unacceptable): Greater than 2.0 μm

[0215] [Image Quality (including Adhesion)] Evaluation was performed using a drawing pattern where the line width (L) / space width (S) is x / (4 - x) {x = 0.1 to 3.9 (varying at 0.1 μm intervals)} (unit: μm). That is, a resist pattern was formed by exposure with the optimal exposure amount, followed by the heating and developing processes described above.

[0216] Figure 2 is a plan view showing an example of a drawing pattern configuration. In the figure, in the drawing area 100A, the exposed area is indicated by reference numeral 10, and the unexposed area (shaded area) is indicated by reference numeral 1. In the area 100A shown in Figure 2, the L / S value is different from that of the area 100 shown in Figure 1. Based on the drawing pattern in Figure 2, it is theoretically expected that a resist pattern with an L / S value corresponding to the width of the unexposed area 1 (S: space) and the width of the exposed area 10 (L: line) will be formed.

[0217] When the obtained resist pattern was observed with an optical microscope at 100x magnification, the minimum line width x at which the line portions (exposed areas) were formed without meandering or missing lines was defined as "adhesion (unit: μm)". A smaller value indicates better adhesion. The observed patterns were judged according to the following criteria: ◎ (Excellent): 1.1 μm or less ○ (Good): Greater than 1.1 μm and 1.3 μm or less △ (Acceptable): Greater than 1.3 μm and 2.0 μm or less × (Poor): Greater than 2.0 μm - (Unmeasurable): Measurement was difficult due to line deformation, missing lines, or the presence of residue in the space areas (unexposed areas).

[0218] The results regarding the above are shown in the table below.

[0219]

[0220]

[0221]

[0222]

[0223]

[0224]

[0225] As can be seen from the table above, it was confirmed that fine resist patterns with line widths and / or space widths of 2 μm or less can be realized according to Examples 1 to 35. In particular, comparing Examples 1 to 35 with Examples 36 to 38, it was confirmed that when resist patterns were formed by direct lithography exposure using light with a maximum wavelength of 402 nm, the effect on resolution was significantly improved when the absorbance at 402 nm was 0.005 or higher compared to when the absorbance at 402 nm was less than 0.005. Similarly, it was confirmed that when resist patterns were formed by projection exposure using light with a maximum wavelength of 365 nm according to Examples 24 to 32, the effect on resolution was significantly improved when the absorbance at 365 nm was 0.005 or higher.

[0226] The present disclosure provides a photosensitive resin laminate capable of realizing a resist pattern with fine line width and / or space width. Such a photosensitive resin laminate can be suitably used in precision metal foil processing such as the manufacture of printed circuit boards, flexible printed circuit boards, lead frames, or metal masks; the manufacture of semiconductor packages such as ball grid arrays (BGAs) or chip-size packages (CSPs); the manufacture of tape substrates such as TABs or COFs; the manufacture of semiconductor bumps; and the manufacture of indium tin oxide (ITO) electrodes or address electrodes, electromagnetic shields, organic interposers, and the like.

[0227] 1: Light-blocking area 10: Transmitting area 100, 100A, 100B: Areas L: Line S: Space

Claims

1. A photosensitive resin laminate having a temporary support and a photosensitive resin layer on the temporary support, wherein the average thickness of the photosensitive resin layer is 16 μm or less, the photosensitive resin layer comprises a photosensitive resin composition containing (A) a binder polymer, (B) a photopolymerizable compound having an ethylenically unsaturated bond, and (C) a photopolymerization initiator, the (A) binder polymer comprises a copolymer having a weight-average molecular weight of 30,000 or less, the content of the (C) photopolymerization initiator is 5.0 parts by mass or more per 100 parts by mass of the total amount of the (A) binder polymer and the (B) photopolymerizable compound, and the absorbance for light at wavelengths of 365 nm and 402 nm per 1 μm of thickness of the photosensitive resin layer is greater than 0.005 and 0.040 or less.

2. The photosensitive resin laminate according to claim 1, wherein the absorbance for light at wavelengths of 365 nm and 402 nm per 1 μm thickness of the photosensitive resin layer is greater than 0.

010.

3. The photosensitive resin laminate according to claim 1, wherein the absorbance for light at wavelengths of 365 nm and 402 nm per 1 μm thickness of the photosensitive resin layer is 0.025 or less.

4. The photosensitive resin laminate according to claim 1, wherein the (C) photopolymerization initiator comprises a dimer of 2,4,5-triarylimidazole, and the content of the 2,4,5-triarylimidazole dimer is 5.0 parts by mass or more with respect to 100 parts by mass of the total amount of the (A) binder polymer and the (B) photopolymerizable compound.

5. The photosensitive resin laminate according to claim 1, wherein the binder polymer (A) contains 30% by mass or more of a copolymer having a weight-average molecular weight of 30,000 or less.

6. The photosensitive resin laminate according to claim 5, wherein the binder polymer (A) contains 50% by mass or more of a copolymer having a weight-average molecular weight of 30,000 or less.

7. The photosensitive resin laminate according to claim 1, wherein the (A) binder polymer comprises a copolymer having a monomer having an aromatic ring as a copolymer component, and the content of the monomer having an aromatic ring is 35% by mass or more based on the total mass of all monomer components of component (A).

8. The photosensitive resin laminate according to claim 1, wherein the (A) binder polymer comprises a copolymer having styrene as a copolymer component, and the styrene content is 35% by mass or more based on the total mass of all monomer components of component (A).

9. The photosensitive resin laminate according to claim 1, wherein the (A) binder polymer comprises a copolymer having a weight-average molecular weight of 25,000 or less.

10. The photosensitive resin laminate according to claim 1, wherein the copolymer having a weight-average molecular weight of 30,000 or less has a value of 2.2 or more and 3.6 or less obtained by the following formula: (acid value (mgKOH / g) + hydroxyl value (mgKOH / g)) / ((parts by mass of constituent units derived from monomers having aromatic rings per 100 parts by mass of copolymer having a weight-average molecular weight of 30,000 or less)).

11. The photosensitive resin laminate according to claim 1, wherein the (A) binder polymer comprises a copolymer having structural units derived from alkyl (meth)acrylate in which the hydrogen atoms of the alkyl group are substituted with hydroxyl groups.

12. The photosensitive resin laminate according to claim 1, wherein the copolymer having a weight-average molecular weight of 30,000 or less has constituent units derived from alkyl (meth)acrylate in which the hydrogen atoms of the alkyl group are substituted with hydroxyl groups, and the content of the constituent units derived from alkyl (meth)acrylate in which the hydrogen atoms of the alkyl group are substituted with hydroxyl groups is in the range of 1% by mass or more and 20% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less.

13. The photosensitive resin laminate according to claim 1, wherein the acid value of the binder polymer (A) is 155 mg KOH / g or less.

14. The photosensitive resin laminate according to claim 1, wherein the copolymer having a weight-average molecular weight of 30,000 or less has an acid value of 155 mgKOH / g or less and contains constituent units derived from styrene and styrene derivatives, and the content of the constituent units derived from styrene and styrene derivatives is in the range of 35% by mass or more and 50% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less.

15. The photosensitive resin laminate according to claim 14, wherein the copolymer having a weight-average molecular weight of 30,000 or less further comprises constituent units derived from methyl (meth)acrylate, and the content of the constituent units derived from methyl (meth)acrylate is in the range of 20% by mass or more and 50% by mass or less, based on the total mass of all monomer components contained in the copolymer having a weight-average molecular weight of 30,000 or less.

16. The above (B) photopolymerizable compound having an ethylenically unsaturated bond contains the following general formula (1): (In the formula, R 1 Each is independently a hydrogen atom or a methyl group, and X 1 O and Y 1 O is independently an oxyethylene group, an oxypropylene group, or an oxybutylene group, and m1, m2, n1, and n2 are the X contained in the compound, respectively. 1 O or Y 1 The photosensitive resin laminate according to claim 1, which contains 10% by mass or more of bisphenol A type di(meth)acrylate, represented by (where m1 + m2 + n1 + n2 is 0 to 9, and each of the O values ​​is an independent integer from 0 to 9).

17. The photosensitive resin laminate according to claim 1, wherein the photopolymerizable compound having an ethylenically unsaturated bond contains 60% by mass or more of a compound containing an aromatic ring.

18. The photosensitive resin laminate according to claim 16, wherein the photopolymerizable compound having an ethylenically unsaturated bond contains 10% by mass or more of a bisphenol A type di(meth)acrylate in which m1 + m2 + n1 + n2 in the general formula (1) is 4 or less.

19. The photosensitive resin laminate according to claim 1, wherein the photosensitive resin layer further contains (E) a hydrogen donor, and the mass ratio of the content of (E) the hydrogen donor to the content of (C) the photopolymerization initiator (content of (E) the hydrogen donor / content of (C) the photopolymerization initiator) is 0.07 or more.

20. The photosensitive resin laminate according to claim 1, wherein the absolute value of the difference between the absorbance of light at a wavelength of 365 nm and the absorbance of light at a wavelength of 402 nm per 1 μm of thickness of the photosensitive resin composition is 0.018 or less.

21. The photosensitive resin laminate according to claim 1, wherein the photosensitive resin composition contains (D) a polymerization inhibitor, the (D) polymerization inhibitor contains a polymerization inhibitor having two or more phenolic hydroxyl groups, and the content is 0.025 parts by mass or more with respect to 100 parts by mass of the total amount of the (A) binder polymer and the (B) photopolymerizable compound.

22. The photosensitive resin laminate according to claim 1, used for forming a pattern with a line width and / or space width of 2 μm or less.

23. The photosensitive resin laminate according to claim 1, wherein the absorbance of the photosensitive resin layer per 1 μm thickness for light with a wavelength of 365 nm is greater than 0.005 and 0.040 or less, and is intended to be exposed to light having a maximum wavelength in the range of 355 to 375 nm.

24. The photosensitive resin laminate according to claim 1, wherein the absorbance of the photosensitive resin layer per 1 μm thickness for light with a wavelength of 402 nm is greater than 0.005 and less than or equal to 0.040, and is intended to be exposed to light having a maximum wavelength in the range of 395 to 410 nm.

25. A photosensitive element comprising a photosensitive resin laminate according to any one of claims 1 to 24 and an intermediate layer, wherein the temporary support, the intermediate layer, and the photosensitive resin layer are sequentially laminated to form a laminated structure.

26. A method for forming a resist pattern, comprising laminating the photosensitive element described in claim 25 onto the surface of a metal plate or a metal-coated insulator, peeling off the temporary support and exposing it to ultraviolet light, and removing the unexposed areas by developing.

27. A method for manufacturing a conductive pattern, comprising etching or plating a substrate on which a resist pattern is formed by the method described in claim 26.

28. The photosensitive resin laminate according to claim 1, wherein the photosensitive resin laminate further comprises a protective film on the side opposite to the temporary support with respect to the photosensitive resin layer, and the protective film is a polyester film with a release layer.

29. The photosensitive resin laminate according to claim 1, wherein the photosensitive resin laminate further comprises a protective film on the side opposite to the temporary support with respect to the photosensitive resin layer, and the protective film is a biaxially oriented polypropylene film.

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