Method for producing electronic board

Abstract

To provide a method for producing an electronic board using a developer while ensuring superior handleability and enabling improved development speed.SOLUTION: According to one embodiment, a method for producing an electronic board includes the step of using a developer containing an alkali agent (component A) and a nonionic surfactant with an HLB of 11 or more and 15 or less (component B) to develop a dry film resist with a thickness of 10 μm or more and 100 μm or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure relates to a method for manufacturing an electronic substrate. [Background technology]

[0002] In recent years, personal computers and various electronic devices have become more energy efficient, faster, and smaller, and the wiring on package substrates mounted on these devices is becoming finer year by year. Until now, the metal mask method has been mainly used to form such fine wiring and connection terminals such as pillars and bumps, but due to its low versatility and the difficulty of responding to the miniaturization of wiring, etc., other new methods are being used. One new method is to use a dry film resist as a thick-film resin mask instead of a metal mask.

[0003] Typically, a resist is applied onto a substrate such as a printed circuit board, a pattern is formed by exposure and development, and then the resist pattern is used as a mask to etch the unmasked areas of the substrate, thereby forming fine wiring. Alkaline developers are widely used for developing resists. For example, Patent Document 1 proposes a developer for a photosensitive resin composition (liquid resist) that contains 0.01 to 20 parts by mass of an alkali metal carbonate per 100 parts by mass of water, 0.01 to 20 parts by mass of an alkali metal bicarbonate per 100 parts by mass of water, and 0.01 to 25 parts by mass of a specific nonionic surfactant per 100 parts by mass of water. Patent Document 2 proposes an alkaline developer containing a specific alkyl glucoside-type nonionic surfactant, a polyoxyalkylene ether-type nonionic surfactant, and an alkaline agent as a developer for a photosensitive resin composition (liquid resist). Patent Document 3 proposes an alkaline developer containing a basic compound, a nonionic surfactant having an HLB of 0 to 4, a nonionic surfactant having an HLB of 6 to 20, and water as a developer for liquid photosensitive resist. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-209117 A [Patent Document 2] JP 2006-259537 A [Patent Document 3] JP 2001-66794 A Summary of the Invention [Problem to be solved by the invention]

[0005] When developing a dry film resist with a thickness of 10 μm or more, the development speed tends to be insufficient. Therefore, the development speed of the developer used to form the pattern of the dry film resist with a thickness of 10 μm or more is important for the formation of fine wiring. In addition, in order to set the optimal development conditions, the developer must have a clear appearance and be easy to handle so that the state of the substrate during processing can be observed. Furthermore, the developer must have excellent developability for fine lines.

[0006] In view of the above, in one aspect, the present disclosure provides a method for manufacturing an electronic substrate using a developer that has good handleability and can improve the development speed. In one aspect, the present disclosure provides a method for manufacturing an electronic substrate using a developer that has good handleability, can improve the development speed, and has excellent developability for fine line portions. [Means for solving the problem]

[0007] In one aspect, the present disclosure relates to a method for producing an electronic substrate, the method including a step of developing a dry film resist having a thickness of 10 μm or more and 100 μm or less using a developer containing an alkaline agent (component A) and a nonionic surfactant having an HLB value of 11 or more and 15 or less (component B). Effect of the Invention

[0008] According to one or more embodiments of the present disclosure, a high-quality electronic substrate can be efficiently manufactured by using a developer that has good handleability and can improve the development speed. Also, according to one or more embodiments of the present disclosure, a high-quality electronic substrate can be efficiently manufactured by using a developer that has good handleability, can improve the development speed, and has excellent developability for fine line portions. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is an illustration showing an example of the appearance of a thin line portion developed using the developer of the first embodiment. [Diagram 2] The figure is an illustration showing an example of the appearance of a thin line portion developed using the developer of Comparative Example 1 (reference). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present disclosure is based on the finding that the development speed and handleability can be improved by using a developer containing an alkaline agent (component A) and a nonionic surfactant (component B) having a specific HLB in the development process of a dry film resist having a thickness of 10 μm or more and 100 μm or less. The present disclosure is also based on the finding that the developer can further improve the developability of fine line portions.

[0011] In one aspect, the present disclosure relates to a method for producing an electronic substrate (hereinafter also referred to as the "electronic substrate production method of the present disclosure"), which includes a step of developing a dry film resist having a thickness of 10 μm or more and 100 μm or less using a developer (hereinafter also referred to as the "developer of the present disclosure") containing an alkaline agent (component A) and a nonionic surfactant (component B) having an HLB of 11 or more and 15 or less.

[0012] According to one or more embodiments of the present disclosure, by using a developer that has good handleability and can improve the development speed, it is possible to efficiently manufacture high-quality electronic substrates. In the present disclosure, "handleability" refers to a property that suppresses the turbidity of the developer's appearance and makes it easy to observe the state of the substrate during processing. Furthermore, according to the present disclosure, in one or more embodiments, by using a developer that is excellent in developing properties for thin line portions, it is possible to improve productivity.

[0013] Although the details of the mechanism of action by which the effects of the present disclosure are expressed are unclear, it is presumed as follows. In the present disclosure, it is believed that the alkaline agent (component A) penetrates into the unexposed areas of the resin mask (dry film resist) and promotes dissociation of the alkali-soluble resin contained in the resin mask, and further causes the repulsion of charges generated by the dissociation, thereby progressing the emulsification and solubilization of the resin mask and resulting in development. In a thick resin mask (for example, 10 to 100 μm thick), the developer is less likely to wet and spread into the gaps in the exposed and cured resin mask pattern, which is thought to reduce the development speed. However, in the present disclosure, the nonionic surfactant (component B) with HLB11 to 15 has good compatibility with the exposed and cured resin mask pattern and is adsorbed thereto, which makes it easier for the developer to wet and spread, which is thought to increase the development speed. Generally, hydrophobic surfactants tend to become cloudy when combined with an alkaline agent (component A); however, in the present disclosure, a nonionic surfactant (component B) with an HLB of 11 to 15 is used, thereby achieving good handling properties without cloudiness. Furthermore, semi-cured resin masks, particularly resin masks in fine line areas, are prone to leaving development residues due to interference and reflection during exposure. However, in the present disclosure, a nonionic surfactant (component B) with HLB of 11 to 15 is adsorbed and promotes emulsification, which is believed to reduce development residues and improve development accuracy, particularly developability in fine line areas. However, the present disclosure need not be construed as being limited to this mechanism.

[0014] In the present disclosure, a "resist" is a material whose physical properties, such as solubility in a developer, change due to light, electron beams, or the like. Resists are broadly divided into negative and positive types based on the reaction method with light or electron beams. A negative resist has a property that its solubility in a developer decreases when exposed to light, and the exposed portion of a layer containing a negative resist (hereinafter also referred to as a "negative resist layer") is used as a resin mask after exposure and development processing. A positive resist has a property that its solubility in a developer increases when exposed to light, and the exposed portion of a layer containing a positive resist (hereinafter also referred to as a "positive resist layer") is removed after exposure and development processing, and the unexposed portion is used as a resin mask. By using a resin mask having such properties, fine connections of a circuit board, such as metal wiring, metal pillars, and solder bumps, can be formed.

[0015] [Development process] The electronic board manufacturing method of the present disclosure includes a step of developing a dry film resist (processing target) having a thickness of 10 μm or more and 100 μm or less using the developer of the present disclosure (hereinafter, also simply referred to as a "developing step"). In one or more embodiments, the developing step includes contacting the processing target with the developer of the present disclosure. In one or more embodiments, the developing step includes removing at least a part of the dry film resist using the developer of the present disclosure. According to the electronic board manufacturing method of the present disclosure, in one or more embodiments, a high-quality electronic board can be efficiently manufactured by using a developer that has good handling properties and can improve the development speed. Also, according to the electronic board manufacturing method of the present disclosure, in one or more embodiments, a high-quality electronic board can be efficiently manufactured by using a developer that has good handling properties, can improve the development speed, and has excellent developability for fine line portions.

[0016] Examples of a method for developing an object to be processed using the developer of the present disclosure, or a method for contacting an object to be processed with the developer of the present disclosure, include immersion development, stirring development, spray development, and paddle development.

[0017] In the developing step, the temperature of the developer to be brought into contact with the object to be treated is preferably, for example, 10 to 50° C., from the viewpoint that the developing power of the developer of the present disclosure is easily exhibited. The time for which the developer of the present disclosure is brought into contact with the object to be treated is preferably, for example, 0.2 to 10 minutes.

[0018] In one or more embodiments, the electronic substrate manufacturing method of the present disclosure may include a step of contacting the developer of the present disclosure with the workpiece, rinsing with water, and drying. Examples of the rinsing method include rinsing with running water. Examples of the drying method include air blow drying. In one or more embodiments, the electronic substrate manufacturing method of the present disclosure may include a step of rinsing the workpiece with water after contacting the developer of the present disclosure with the workpiece.

[0019] [Processing object] In one or more embodiments, the object to be treated is a dry film resist having a thickness of 10 μm or more and 100 μm or less. In one or more embodiments, the dry film resist is a negative dry film resist or a positive dry film resist, and from the viewpoint of the effect of the developer of the present disclosure, a negative dry film resist is preferable. In one or more embodiments, the thickness of the dry film resist is 10 μm or more and 100 μm or less, more preferably 15 μm or more and 60 μm or less. In one or more embodiments, the object to be treated may be a dry film resist having a thickness of 10 μm or more and 100 μm or less laminated on a substrate. In one or more embodiments, the dry film resist having a thickness of 10 μm or more and 100 μm or less laminated on a substrate may be a partially exposed dry film resist, a non-exposed dry film resist, or the like. The substrate may be an electronic substrate. Examples of the electronic substrate may include a glass epoxy multilayer substrate, a printed circuit board, a wafer, a copper plate, an aluminum plate, or the like. Examples of the object to be treated include electronic components having a dry film resist having a thickness of 10 μm to 100 μm, and intermediate products thereof. Examples of the electronic components include at least one component selected from a glass epoxy multilayer board, a printed circuit board, a wafer, and a metal plate such as a copper plate or an aluminum plate. The intermediate products include intermediate products in the manufacturing process of electronic components.

[0020] [Developer] In one or a plurality of embodiments, the developer of the present disclosure contains an alkaline agent (component A) and a nonionic surfactant having an HLB value of 11 to 15. The components contained in the developer of the present disclosure are described below.

[0021] <Alkaline agent (ingredient A)> The alkaline agent (hereinafter also referred to as "component A") contained in the developer of the present disclosure may be one type or a combination of two or more types. From the viewpoints of handling, improving the development speed, and improving the developability of fine lines, an alkali metal carbonate is preferred as Component A. Examples of the alkali metal carbonate include sodium carbonate and potassium carbonate, and from the same viewpoint, sodium carbonate is preferred.

[0022] The content of component A in the developer of the present disclosure is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, from the viewpoints of handling, improving the development speed, and improving the developability of thin lines, and from the same viewpoint, it is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 2% by mass or less. From the same viewpoint, the content of component A in the developer of the present disclosure is preferably 0.1% by mass or more and 5% by mass or less, more preferably 0.3% by mass or more and 3% by mass or less, and even more preferably 0.5% by mass or more and 2% by mass or less. When component A is a combination of two or more kinds, the content of component A refers to the total content thereof.

[0023] In the present disclosure, "the content of each component in the developer" refers to the content of each component at the time of development, that is, at the time when the developer starts to be used for development processing. In one or more embodiments, the content of each component in the developer of the present disclosure can be regarded as the blending amount of each component in the developer of the present disclosure.

[0024] <Nonionic surfactant with HLB of 11 or more and 15 or less (Component B)> The nonionic surfactant (hereinafter also referred to as "Component B") having an HLB of 11 or more and 15 or less contained in the developer of the present disclosure may be one kind or a combination of two or more kinds.

[0025] From the viewpoints of handleability, improvement of development speed, and improvement of developability in fine line portions, the HLB of Component B is 11 or more, preferably 11.5 or more, more preferably 12 or more, and from the same viewpoints, it is 15 or less, preferably 14 or less, more preferably 13 or less. From the same viewpoints, the HLB of Component B is 11 or more and 15 or less, preferably 11.5 or more and 14 or less, more preferably 12 or more and 13 or less. In the present disclosure, the HLB of the surfactant is a value obtained by the Griffin method.

[0026] Examples of Component B include polyoxyethylene alkyl ether having an HLB of 11 or more and 15 or less, and polyoxyethylene distyrenated phenyl ether having an HLB of 11 or more and 15 or less. Examples of polyoxyethylene alkyl ether having an HLB of 11 or more and 15 or less include polyoxyethylene(6) lauryl ether (HLB: 12.1). Examples of polyoxyethylene distyrenated phenyl ether having an HLB of 11 or more and 15 or less include polyoxyethylene distyrenated phenyl ether (HLB: 12.8). Among these, from the viewpoints of handleability, improvement of development speed, and improvement of developability in fine line portions, polyoxyethylene alkyl ether having an HLB of 11 or more and 15 or less is preferable, and polyoxyethylene(6) lauryl ether (HLB: 12.1) is more preferable. The numerical value in () represents the average number of moles of ethylene oxide (EO) added.

[0027] From the viewpoints of handleability, improvement in development speed, and improvement in developability of fine line portions, the content of Component B in the developer of the present disclosure is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, still more preferably 0.5% by mass or more, and from the same viewpoints, preferably 5% by mass or less, more preferably 3% by mass or less, still more preferably 2% by mass or less. From the same viewpoints, the content of Component B in the developer of the present disclosure is preferably 0.1% by mass or more and 5% by mass or less, more preferably 0.3% by mass or more and 3% by mass or less, still more preferably 0.5% by mass or more and 2% by mass or less. When Component B is a combination of two or more types, the content of Component B refers to their total content.

[0028] From the viewpoints of improvement in development speed and improvement in developability of fine line portions, the mass ratio A / B (content of Component A / content of Component B) of Component A and Component B in the developer of the present disclosure is preferably 100 or less, more preferably 50 or less, and from the same viewpoints, preferably 20 or more, more preferably 1 or more, still more preferably 1.5 or more. From the same viewpoints, the mass ratio A / B in the developer of the present disclosure is preferably 1 or more and 100 or less, more preferably 1 or more and 50 or less, still more preferably 1.5 or more and 20 or less.

[0029] <Nonionic surfactant (Component C) with HLB exceeding 4 and 7 or less> In one or more embodiments, the developer of the present disclosure may further contain a nonionic surfactant (hereinafter also referred to as "Component C") with an HLB exceeding 4 and 7 or less. Component C may be one type or a combination of two or more types.

[0030] From the viewpoint of improvement in development speed, the HLB of Component C is 7 or less, preferably 6.8 or less, more preferably 6.6 or less, and from the viewpoints of improvement in development speed and handleability, it exceeds 4, and more preferably 5 or more. From the same viewpoints, the HLB of Component C exceeds 4 and is 7 or less, preferably 5 or more and 6.8 or less, more preferably 5 or more and 6.6 or less.

[0031] As component C, for example, polyoxyethylene alkyl ethers with an HLB greater than 4 and less than or equal to 7 can be mentioned. Examples of polyoxyethylene alkyl ethers with an HLB greater than 4 and less than or equal to 7 include polyoxyethylene(2) lauryl ether (HLB: 6.4). The numerical value in parentheses represents the average number of moles of EO added.

[0032] From the perspective of handleability, the content of component C in the developer of the present disclosure is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, still more preferably 0.1% by mass or more, and from the perspective of handleability, preferably 1% by mass or less, more preferably 0.5% by mass or less, still more preferably 0.2% by mass or less. From the same perspective, the content of component C in the developer of the present disclosure is preferably 0.01% by mass or more and 1% by mass or less, more preferably 0.05% by mass or more and 0.5% by mass or less, still more preferably 0.1% by mass or more and 0.2% by mass or less. When component C is a combination of two or more types, the content of component C refers to their total content.

[0033] From the perspective of handleability, the content of component C in all surfactants (100% by mass) contained in the developer of the present disclosure is preferably 25% by mass or less, more preferably 20% by mass or less, still more preferably 15% by mass or less, and even more preferably 0% by mass (that is, not contained).

[0034] From the perspective of handleability, the mass ratio A / (B + C) of the content of component A and the total content of components B and C in the developer of the present disclosure is preferably 1 or more, more preferably 1.5 or more, still more preferably 2 or more, and even more preferably 5 or more, and from the perspective of handleability, preferably 100 or less, more preferably 50 or less, still more preferably 20 or less. From the same perspective, the mass ratio A / (B + C) in the developer of the present disclosure is preferably 1 or more and 100 or less, more preferably 1.5 or more and 100 or less, still more preferably 2 or more and 50 or less, and even more preferably 5 or more and 20 or less.

[0035] <Nonionic surfactant with HLB of 4 or less (component D)> In one or more embodiments, the developer of the present disclosure may contain a nonionic surfactant having an HLB of 4 or less (hereinafter also referred to as "component D"), and in one or more other embodiments, may not contain component D. Component D may be one type or a combination of two or more types.

[0036] Examples of component D include sorbitan fatty acid esters having an HLB of not more than 4. Examples of sorbitan fatty acid esters having an HLB of not more than 4 include sorbitan tristearate (HLB: 2.1).

[0037] From the viewpoint of handleability, the content of component D in the developer of the present disclosure is preferably 0.5% by mass or less, more preferably 0.3% by mass or less, even more preferably 0.1% by mass or less, and even more preferably 0% by mass (i.e., not contained).

[0038] <Water (ingredient E)> In one or more embodiments, the developer of the present disclosure further contains water (hereinafter, also referred to as "Component E"). In one or more embodiments, examples of Component E include ion-exchanged water, RO water, distilled water, pure water, and ultrapure water.

[0039] The content of Component E in the developer of the present disclosure can be the remainder excluding Component A, Component B, and optional components (Component C, Component D, and other components described below). The content of component E in the developer of the present disclosure is preferably 90% by mass or more, more preferably 95% by mass or more, and even more preferably 97% by mass or more, from the viewpoints of improving the development speed, improving the developability of thin lines, and handling properties, and from the same viewpoints, it is preferably 99.9% by mass or less, more preferably 99.5% by mass or less, and even more preferably 99% by mass or less. From the same viewpoints, the content of component E in the developer of the present disclosure is preferably 90% by mass or more and 99.9% by mass or less, more preferably 95% by mass or more and 99.5% by mass or less, and even more preferably 97% by mass or more and 99% by mass or less.

[0040] <Other ingredients> In one or more embodiments, the developer of the present disclosure may further contain other components as necessary within a range that does not impair the effects of the present disclosure. Examples of other components include components that can be used in normal developers, such as surfactants other than components B to D, stabilizers, and anticorrosive agents.

[0041] In one or more embodiments, the developer of the present disclosure may be substantially free of alkylated oligosaccharides. For example, the content of alkylated oligosaccharides in the developer of the present disclosure is preferably less than 5% by mass, more preferably 1% by mass or less, even more preferably 0.1% by mass or less, and even more preferably 0% by mass (i.e., no alkylated oligosaccharides). In one or more embodiments, the developer of the present disclosure may be substantially free of alkali metal bicarbonate. For example, the content of alkali metal bicarbonate in the developer of the present disclosure is preferably less than 0.01% by mass, and more preferably 0% by mass (i.e., no content). In one or more embodiments, the developer of the present disclosure may be substantially free of an alkyl glucoside type nonionic surfactant. For example, the content of the alkyl glucoside type nonionic surfactant in the developer of the present disclosure is preferably less than 0.01% by mass, and more preferably 0% by mass (i.e., no surfactant is contained).

[0042] In one or more embodiments, the developer of the present disclosure is preferably substantially free of nitrogen-containing compounds and phosphorus-containing compounds from the viewpoint of reducing the wastewater treatment load, suppressing eutrophication of the wastewater area, and avoiding toxicity to improve safety. In the present disclosure, "substantially free of nitrogen-containing compounds and phosphorus-containing compounds" means that the total content of the nitrogen-containing compounds and phosphorus-containing compounds in the developer of the present disclosure is less than 0.1% by mass. From the viewpoint of reducing the wastewater treatment load and suppressing eutrophication of the wastewater area, the total content of the nitrogen-containing compounds and phosphorus-containing compounds in the developer of the present disclosure is preferably 0.05% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0% by mass (i.e., no compounds). Examples of the nitrogen-containing compound include at least one or a combination of two or more selected from amines and their salts, ammonia, and ammonium salts. Examples of the amines include amino alcohols such as monoethanolamine and diethanolamine. Examples of the ammonium salts include quaternary ammonium salts such as tetramethylammonium hydroxide (TMAH). Examples of the phosphorus-containing compound include at least one or a combination of two or more selected from phosphoric acid and its salts, inorganic phosphoric acids such as condensed phosphoric acids such as pyrophosphoric acid, polyphosphoric acid, and metaphosphoric acid and their salts, organic phosphoric acids, and phosphate esters.

[0043] [Manufacturing method of developer] In one or more embodiments, the developer of the present disclosure can be produced by blending component A, component B, and the above-mentioned optional components (component C, component D, component E, and other components) as necessary by a known method. For example, the developer of the present disclosure can be produced by blending at least component A and component B. Thus, the present disclosure relates to a method for producing a developer, which includes a step of blending at least component A and component B. In the present disclosure, "blending" includes mixing component A, component B, and the above-mentioned optional components (component C, component D, component E, and other components) as necessary simultaneously or in any order. In the method for producing a developer of the present disclosure, the preferred blending amount of each component can be the same as the preferred content of each component of the developer of the present disclosure described above.

[0044] The developer according to the present disclosure may be of a so-called one-component type, in which all components are premixed and supplied to the market, or of a so-called two-component type, in which components are mixed when used. The developer of the present disclosure may be stored and supplied in a concentrated state within a range that does not impair its storage stability. The concentrate of the developer of the present disclosure can be used by appropriately diluting it with water (component E) so that each component has the above-mentioned content (i.e., the content at the time of development) when used. The dilution ratio can be, for example, 3 to 100 times. In one or a plurality of embodiments, the developer of the present disclosure is a two-part developer including an agent containing component A and an agent containing an agent other than component A in a concentrated state. In one or more embodiments, the developer of the present disclosure may contain an agent (first agent) containing component A and an agent (second agent) containing component B in a mutually unmixed state, and the first and second liquids may be mixed at the time of use (two-liquid developer). Each of the first and second agents may contain optional components (component C, component D, component E, other components) as necessary. After the first and second agents are mixed, they may be diluted with water (component E) as necessary.

[0045] From the viewpoints of handling, improving the development speed, and improving the developability of thin lines, the pH of the developer of the present disclosure is preferably 10 or more, more preferably 10.5 or more, and even more preferably 11 or more, and from the same viewpoints, it is preferably 13 or less, more preferably 12.5 or less, and even more preferably 12 or less. From the same viewpoints, the pH of the developer of the present disclosure is preferably 10 or more and 13 or less, more preferably 10.5 or more and 12.5 or less, and even more preferably 11 or more and 12 or less. EXAMPLES

[0046] The present disclosure will be specifically described below with reference to examples, but the present disclosure is not limited to these examples in any way.

[0047] 1. Preparation of Developers of Examples 1 to 7 and Comparative Examples 1 to 5 The components shown in Tables 1 and 2 were blended in the amounts (mass %, active content) shown in Tables 1 and 2 and mixed by stirring to prepare the developers of Examples 1 to 7 and Comparative Examples 1 to 5.

[0048] The developers of Examples 1 to 7 and Comparative Examples 1 to 5 were prepared using the following materials. (Component A) Sodium carbonate [manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.] (Component B) Polyoxyethylene (6) lauryl ether [Kao Corporation, EO addition mole number: 6, HLB: 12.1] Polyoxyethylene distyrenated phenyl ether [Kao Corporation, HLB: 12.8] (Component C) Polyoxyethylene (2) lauryl ether [Kao Corporation, EO addition mole number: 2, HLB: 6.4] (Component D) Sorbitan tristearate [Kao Corporation, HLB: 2.1] (Other Ingredients) Polyoxyethylene (4) lauryl ether [Kao Corporation, EO addition mole number: 4, HLB: 9.7] Polyoxyethylene (23) lauryl ether [Kao Corporation, EO addition mole number: 23, HLB: 16.9] (Component E) Water [Pure water of 1μS / cm or less produced using the Organo Corporation pure water system G-10DSTSET]

[0049] 2. Evaluation of Developers The prepared developers of Examples 1 to 7 and Comparative Examples 1 to 5 were evaluated as follows.

[0050] [Test piece I for evaluating development speed] Test piece I is 120 mm x 120 mm in size and has a resin mask layer of negative dry film resist 60 μm thick on the surface of a glass epoxy multilayer substrate, and is exposed and cured so that the line / space of the finished pattern (dry film resist pattern) is 100 μm / 100 μm. [Test piece for evaluating fine line development II] Test piece II is 120 mm x 120 mm in size and has a resin mask layer of negative dry film resist 60 μm thick on the surface of a glass epoxy multilayer substrate, and is exposed and cured so that the line / space of the finished pattern (dry film resist pattern) is 60 μm / 60 μm.

[0051] [Evaluation of development speed] Test piece I was immersed (immersion development) in the developer (Examples 1-7, Comparative Examples 1-5) under stirring conditions of 30°C and 600 rpm, while being visually observed, and the time until the resin mask (dry film resist) in the portion not exposed to light and cured was developed and the base of test piece I became visible was measured. Using the developer of Comparative Example 1 (1% aqueous sodium carbonate solution) as a reference, the development speeds of Examples 1-7 and Comparative Examples 2-4 were evaluated based on the following evaluation criteria. The development time of Comparative Example 1 (reference) was 2 minutes. The results are shown in Tables 1-2. <Evaluation criteria> A: The development time is reduced by 15% or more compared to the reference. B: The development time is reduced by 10% to less than 15% compared to the reference. C: The development time is reduced by 5% to less than 10% compared to the reference. D: The development time is shorter or longer than the reference by less than 5%.

[0052] [Evaluation of handling] The ease of visual observation (handling properties) when evaluating the above-mentioned development speed using the developers (Examples 1 to 7, Comparative Examples 1 to 5) was evaluated based on the following evaluation criteria. Here, ease of visual observation refers to whether or not foreign matter (precipitates, etc.) in the developer is easily observed, and whether or not the state of development is easily visible (whether or not the state of the substrate after development is easily observed). The results are shown in Tables 1 and 2. <Evaluation criteria> A: The developer is transparent, and the presence or absence of foreign matter such as sediment and the state of development can be clearly seen. B: The developer is slightly cloudy, but the presence or absence of foreign matter such as precipitates and the state of development can be seen. C: The developer is cloudy, but there is no sediment or other foreign matter, and the development is somewhat visible. D: The developer is cloudy, and it is very difficult to see whether there is any sediment or other foreign matter, or how the development is progressing.

[0053] [Evaluation of fine line development] After adding 3 kg of each developer to a 5L stainless steel beaker, the developer was heated to 30°C, and the developer was circulated in a box-type spray washer equipped with a one-fluid nozzle (full cone type) J020 (manufactured by Ikeuchi Co., Ltd.) as a spray nozzle. The nozzle was operated so that the spray hits the test piece II evenly, and the test piece II was sprayed (pressure: 0.15 MPa, spray distance: 11 cm) for twice the development time (2 minutes) (4 minutes). Then, water was poured for 30 seconds to rinse, and then dried by nitrogen blowing. In order to make it easier to observe the bottom of the fine line part (the boundary part between the fine line part and the substrate) of the dry film resist pattern after development with a scanning electron microscope, a conductive film (Pt-Pd) was vapor-deposited by the following method. Thereafter, the fine line part of the developed dry film resist pattern was observed using a scanning electron microscope, and the fine line developability of Examples 1, 3 and Comparative Example 5 was evaluated based on the following evaluation criteria, using Comparative Example 1 (1% aqueous solution of sodium carbonate) as a reference. The results are shown in Table 2. Conductive film deposition method: Using a Hitachi E-1030 (ion sputtering device), the conductive film was deposited by performing processing for 2 minutes at an ion current of 15 mA. <Evaluation criteria> A: The development residue at the bottom of the fine line of the dry film resist pattern is clearly less than that of the reference. B: The development residue at the bottom of the fine line of the dry film resist pattern is less than that of the reference. C: The development residue at the bottom of the fine line of the dry film resist pattern is slightly less than that of the reference. D: The development residue at the bottom of the fine line of the dry film resist pattern is equal to or greater than that of the reference.

[0054] Here, Fig. 1 shows an example of the appearance of a fine line portion 1 of a dry film resist pattern developed using the developer of Example 1. Fig. 2 shows an example of the appearance of a fine line portion 1 of a dry film resist pattern developed using Comparative Example 1 (aqueous solution of 1% sodium carbonate). When development was performed using the developer of Comparative Example 1 (1% aqueous sodium carbonate solution, reference), a large amount of development residue 3 (spreading of the hem, hem remaining) was generated at the hem of the thin line portion 1 on the substrate surface 2 after development, as shown in Figure 2. On the other hand, when development was performed using the developer of Example 1, as shown in Figure 1, the amount of development residue 3 generated at the hem of the thin line portion 1 on the substrate surface 2 after development was smaller than that of the reference (Figure 1), indicating that the developability of the thin line portion was improved (i.e., the development accuracy was improved).

[0055] [Table 1]

[0056] [Table 2]

[0057] As shown in Table 1, Examples 1 to 7, which used a developer containing an alkaline agent (component A) and a nonionic surfactant (component B) with an HLB of 11 to 15, showed higher development speeds and better handleability than Comparative Example 1, which used a developer containing component A but not component B, Comparative Example 2, which used a developer containing component B but not component A, and Comparative Examples 3 and 4, which used developers containing component A and a nonionic surfactant other than component B. Furthermore, as shown in Table 2, Examples 1 and 3, which used a developer containing an alkaline agent (component A) and a nonionic surfactant (component B) with an HLB of 11 to 15, showed higher development speeds and were superior in handleability and developability of thin lines compared to Comparative Example 1, which used a developer containing component A but not component B, and Comparative Example 5, which used a developer containing component A and a nonionic surfactant other than component B. [Industrial Applicability]

[0058] According to the present disclosure, by using a developer that has good handleability and can improve the development speed, it is possible to improve the performance and reliability of the manufactured electronic substrates, and to improve the productivity of the electronic substrates. [Explanation of symbols]

[0059] 1 Fine line part of dry film resist pattern 2. Board surface 3. Development residue

Claims

1. A method for manufacturing an electronic substrate, comprising the step of developing a dry film resist with a thickness of 10 μm to 100 μm using a developer containing an alkaline agent (component A) and a nonionic surfactant (component B) having an HLB of 11 to 15.

2. The manufacturing method according to claim 1, wherein component A contained in the developer is an alkali metal carbonate.

3. The manufacturing method according to claim 1 or 2, wherein the content of a nonionic surfactant (component C) with an HLB greater than 4 and less than or equal to 7 in the total surfactants contained in the developer is 25% by mass or less.

4. The manufacturing method according to claim 1 or 2, wherein the developer does not contain a nonionic surfactant (component D) with an HLB of 4 or less.

5. The manufacturing method according to claim 1 or 2, wherein component B contained in the developer is a polyoxyethylene alkyl ether with an HLB of 11 or more and 15 or less.

6. The manufacturing method according to claim 3, wherein the mass ratio A / (B+C) of the content of component A in the developer to the total content of components B and C is 1 or more and 100 or less.

7. The manufacturing method according to claim 1 or 2, wherein the developer substantially does not contain nitrogen-containing compounds and phosphorus-containing compounds.

Images