Etching liquid composition, etching method, and method for producing substrate

Abstract

Provided is an etching liquid composition capable of sufficiently etching a layer containing copper in the depth direction while sufficiently suppressing side etching. An etchant composition for etching a layer containing copper, the etchant composition containing (A) a compound represented by general formula (1) (in general formula (1), R1 and R2 each independently represent a hydrogen atom, an amino group, a thiol group, a phenyl group or a carboxyl group; in the formula, when one of R1 and R2 is a hydrogen atom, the other is a thiol group, a phenyl group, or a carboxyl group. (B) at least one component selected from the group consisting of bivalent copper ions and trivalent iron ions; and (C) an aqueous solution of an acid and water.

Description

Technical Field

[0001] This invention relates to an etching solution composition containing specific components, an etching method using the same, and a method for manufacturing a substrate. Background Technology

[0002] As methods for forming circuits in printed circuit boards, semiconductor packaging substrates, etc., the following methods are known: methods for subsequently adding circuit patterns to the substrate; and subtraction methods for forming circuit patterns by removing unwanted portions from metal foil on the substrate. Currently, etching is commonly used in the manufacture of printed circuit boards as a low-cost subtraction method. Moreover, with the increasing performance and miniaturization of electronic devices in recent years, there is a demand for finer patterns on printed circuit boards, and the development of etching solutions capable of forming fine patterns on substrates is underway.

[0003] For example, Patent Document 1 discloses an etching solution capable of etching copper, comprising: copper chloride and hydrochloric acid, and 5-amino-1H-tetrazole, 1H-tetrazole, or 5-methyl-1H-tetrazole. Patent Document 2 discloses an etching solution for nickel-containing layers, comprising: ferric chloride and hydrogen chloride, and 5-aminotetrazole or benzotriazole.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2021-116449

[0007] Patent Document 2: Japanese Patent Application Publication No. 2018-178142 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] However, the etching solutions disclosed in Patent Documents 1 and 2 cannot perform etching with high anisotropy, that is, they cannot fully etch along the depth direction while sufficiently suppressing lateral etching. Therefore, there is a problem that fine patterns with the desired dimensional accuracy cannot be formed.

[0010] Therefore, the present invention aims to provide an etching solution composition capable of sufficiently suppressing lateral etching while performing sufficient etching along the depth direction for copper-containing layers. Furthermore, the present invention aims to provide an etching method using the above-described etching solution composition and a substrate manufacturing method.

[0011] Solution for solving the problem

[0012] The inventors conducted repeated and in-depth research in order to obtain the above-mentioned etching solution composition, and found that the composition containing specific components can solve the above-mentioned problems, thus obtaining the present invention.

[0013] That is, according to the present invention, an etching solution composition is provided for etching a copper-containing layer, which is an aqueous solution containing (A) a compound represented by the following general formula (1), (B) at least one component selected from the group consisting of divalent copper ions and trivalent iron ions, and (C) an acid and water.

[0014]

[0015] (In the aforementioned general formula (1), R) 1 and R 2 Each can independently represent a hydrogen atom, amino group, thiol group, phenyl group, or carboxyl group. Among them, R... 1 and R 2 (If one of the atoms is a hydrogen atom, the other is a thiol group, phenyl group, or carboxyl group.)

[0016] In addition, according to the present invention, an etching method is provided, comprising the following steps: etching a copper-containing layer with the above-described etching solution composition.

[0017] Furthermore, according to the present invention, a method for manufacturing a substrate is provided, comprising the following steps: etching a copper-containing layer with the above-described etching solution composition.

[0018] The effects of the invention

[0019] According to the present invention, an etching solution composition is provided that enables sufficient etching along the depth direction while adequately suppressing lateral etching of copper-containing layers. Furthermore, according to the present invention, an etching method using the above-described etching solution composition and a substrate manufacturing method are provided. Attached Figure Description

[0020] Figure 1 A cross-sectional view of the etched test substrate is shown for illustrative purposes. Detailed Implementation

[0021] Hereinafter, embodiments of the present invention will be described in detail. An etching solution composition of one embodiment of the present invention (hereinafter sometimes referred to as "the composition") is an aqueous solution containing (A) component: a compound represented by general formula (1) (hereinafter also referred to as "(A) component"), (B) component: at least one component selected from the group consisting of divalent copper ions and trivalent iron ions (hereinafter also referred to as "(B) component"), (C) component: an acid (hereinafter also referred to as "(C) component"), and water.

[0022] This composition is an etching solution composition for etching copper-containing layers. Examples of copper-containing layers include at least one layer selected from the group consisting of copper and copper alloys. Examples of copper alloys include copper-silver alloys, copper-titanium alloys, copper-beryllium alloys, copper-nickel alloys, copper-iron alloys, and copper-aluminum alloys. This composition is particularly suitable as an etching solution composition for etching layers containing at least one layer selected from the group consisting of copper, copper-titanium alloys, copper-beryllium alloys, copper-nickel alloys, and copper-iron alloys. Furthermore, this composition is preferably used for etching at least one layer selected from the group consisting of copper layers and copper alloy layers, and the copper-containing layer to be etched is more preferably a copper alloy layer. As this copper alloy, at least one layer selected from the group consisting of copper-titanium alloys, copper-beryllium alloys, copper-nickel alloys, and copper-iron alloys is even more preferred. This composition is particularly suitable as an etching solution composition for etching copper-titanium alloys.

[0023] In this specification, "etching" refers to a shaping or surface processing technique that utilizes the corrosive action of chemicals, etc. Specific uses of this composition include, for example, being a remover, surface smoother, surface roughener, patterning agent, and cleaning solution for trace amounts of components adhering to a substrate. If this composition is used to form patterns with fine three-dimensional structures, patterns of desired shapes such as rectangles can be obtained; therefore, this composition is suitable for use as a patterning agent. Furthermore, because this composition removes copper-containing layers quickly, it is also suitable for use as a remover.

[0024] (A) is a compound represented by the general formula (1) below. One of the components (A) may be used alone or in combination of two or more.

[0025]

[0026] (In general formula (1), R) 1 and R 2 Each can independently represent a hydrogen atom, amino group, thiol group, phenyl group, or carboxyl group. Among them, R... 1 and R 2 (If one of the atoms is a hydrogen atom, the other is a thiol group, phenyl group, or carboxyl group.)

[0027] Preferred specific examples of compounds represented by general formula (1) include compounds represented by chemical formulas No. 1 to No. 13 below. In chemical formulas No. 1 to No. 13 below, "Ph" represents phenyl.

[0028]

[0029] In the compounds represented by general formula (1), R in general formula (1) is preferred.1 Compounds containing hydrogen atoms or amino groups. Furthermore, in compounds represented by general formula (1), R in general formula (1) is preferred. 2 Compounds that are amino or thiol groups. Among these, R in general formula (1) is more preferred. 1 It is a hydrogen atom or an amino group, and R 2 Compounds that are amino or thiol groups. In other words, among chemical formulas No. 1 to No. 13, compounds represented by chemical formulas No. 1, No. 4, and No. 5 are more preferred.

[0030] As component (A), R in general formula (1) is further preferred. 1 and R 2 All are amino compounds, i.e., compounds represented by Chemical Formula No. 4. By using the compound represented by Chemical Formula No. 4 as component (A), it is possible to etch copper-containing layers with even higher anisotropy. That is, for copper-containing layers, it is possible to further and sufficiently etch along the depth direction while further and sufficiently suppressing lateral etching.

[0031] The content of component (A) in this composition is preferably 0.01 to 10% by mass. By including the content of component (A) within the above range, it is possible to etch copper-containing layers with higher anisotropy. From this viewpoint, the content of component (A) in this composition is more preferably 0.05 to 8% by mass, further preferably 0.1 to 5% by mass, and particularly preferably 0.2 to 3% by mass. In this specification, the content (by mass%) of a component in this composition refers to the content (concentration) of that component based on the total mass of the composition.

[0032] In this composition, the mass ratio of component (A) to the total of components (A) and (B) {(A) / ((A)+(B))} is preferably 0.001 to 0.3. By having the mass ratio {(A) / ((A)+(B))} within the above range, the copper-containing layer can be etched with higher anisotropy. From this viewpoint, the mass ratio {(A) / ((A)+(B))} is more preferably 0.003 to 0.2, further preferably 0.005 to 0.1, and particularly preferably 0.01 to 0.06.

[0033] (B) The component is selected from divalent copper ions (copper(II) ions, Cu). 2+ ) and trivalent iron ions (iron(III) ions, Fe 3 +The composition comprises at least one component of the group consisting of (B). As component (B), divalent copper ions and trivalent iron ions are used individually or in combination. The composition can contain divalent copper ions by blending with a copper (II) compound. That is, a copper (II) compound can be used as a source of divalent copper ions. Furthermore, the composition can contain trivalent iron ions by blending with an iron (III) compound. That is, an iron (III) compound can be used as a source of trivalent iron ions.

[0034] Examples of copper (II) compounds include copper chloride (II), copper bromide (II), copper sulfate (II), and copper hydroxide (II). Examples of iron (III) compounds include ferric chloride (III), ferric bromide (III), ferric iodide (III), ferric sulfate (III), ferric nitrate (III), and ferric acetate (III). These copper (II) and iron (III) compounds can be used alone or in combination of two or more. Among these compounds, copper chloride (II) and ferric chloride (III) are preferred from the perspective of easy control of the etching rate and the ability to achieve a sufficient etching rate; copper chloride (II) is even more preferred.

[0035] The content of component (B) in this composition is preferably 1 to 35% by mass. By including the content of component (B) within the above range, the etching rate can be easily controlled, and a sufficient etching rate can be achieved. From these viewpoints, the content of component (B) in this composition is more preferably 3 to 30% by mass, more preferably 5 to 25% by mass, and particularly preferably 10 to 20% by mass. When using divalent copper ions or trivalent iron ions alone, the concentration of component (B) refers to the concentration of divalent copper ions or trivalent iron ions. Furthermore, when used in combination (mixed) of divalent copper ions and trivalent iron ions, it refers to the sum of the concentrations of divalent copper ions and trivalent iron ions. For example, if the etching solution composition contains 10% by mass of copper(II) chloride, the concentration of component (B) in the etching solution composition is approximately 4.7% by mass. Additionally, if, for example, the etching solution composition contains 10% by mass of copper(II) chloride and 10% by mass of ferric(III) chloride, the concentration of component (B) in the etching solution composition is approximately 8.2% by mass.

[0036] Component (C) is an acid. As component (C), an inorganic acid is preferred from the perspective of easily dissolving component (A) and achieving a sufficient etching rate. Among the inorganic acids, at least one from the group consisting of hydrogen chloride, nitric acid, and sulfuric acid is more preferred, and hydrogen chloride is even more preferred.

[0037] The content of component (C) in this composition is preferably 1 to 35% by mass. By including the content of component (C) within the above range, it is less likely to cause corrosion or other adverse conditions of the device components and a sufficient etching rate can be achieved. From these viewpoints, the content of component (C) in this composition is more preferably 1.5 to 25% by mass, more preferably 2 to 20% by mass, and particularly preferably 2.5 to 15% by mass.

[0038] In this composition, the mass ratio of component (C) to the total of components (A) and (B) {(C) / ((A)+(B))} is preferably 0.01 to 0.5. When the mass ratio {(C) / ((A)+(B))} is within the above range, adverse conditions such as corrosion of the device components are less likely to occur, and a sufficient etching rate can be achieved. From these viewpoints, the mass ratio {(C) / ((A)+(B))} is more preferably 0.03 to 0.4, further preferably 0.05 to 0.3, and particularly preferably 0.1 to 0.3.

[0039] This composition is an aqueous solution containing water as an essential component, wherein all components are dissolved in water. Preferably, water that has been deionized, purified, or ultrapure has been used to remove ionic substances and impurities. The water content in this composition is preferably 20–80% by mass, more preferably 20–70% by mass, and even more preferably 30–60% by mass.

[0040] From the perspective of enabling etching with higher anisotropy, this composition preferably further contains a (D) specific gravity adjuster. Examples of (D) components include calcium chloride, potassium chloride, magnesium chloride, and sodium chloride. One or more of these can be used alone or in combination. In one embodiment, this composition preferably further contains at least one (D) specific gravity adjuster selected from the group consisting of calcium chloride, potassium chloride, magnesium chloride, and sodium chloride. Among the (D) components, potassium chloride and sodium chloride are more preferred, and sodium chloride is even more preferred.

[0041] The content of component (D) in this composition is preferably 0.1 to 15% by mass. By having the content of component (D) in the above range, it is possible to etch the copper-containing layer with higher anisotropy. From this point of view, the content of component (D) in this composition is more preferably 0.3 to 13% by mass, more preferably 0.5 to 10% by mass, and particularly preferably 1 to 5% by mass.

[0042] From the perspective of being able to perform etching with higher anisotropy, the specific gravity of this composition is preferably 1.2 to 1.6, more preferably 1.3 to 1.5.

[0043] This composition may contain known additives and solvents as components other than (A), (B), (C), (D), and water, without impairing the effects of the present invention. Examples of additives include stabilizers for the etching solution composition, solubilizers for each component, pH adjusters, viscosity adjusters, wettability improvers, chelating agents, oxidizing agents, reducing agents, and surfactants. One or more of these additives may be used alone or in combination. The content of each of the above-mentioned additives in this composition is preferably in the range of 0.001 to 50% by mass, more preferably in the range of 0.001 to 40% by mass, and even more preferably in the range of 0.001 to 30% by mass.

[0044] Examples of pH adjusters include, for instance, inorganic acids other than component (C), such as sulfuric acid and nitric acid, and their salts; water-soluble organic acids and their salts; alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; alkaline earth metal hydroxides such as calcium hydroxide, strontium hydroxide, and barium hydroxide; alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate; alkali metal bicarbonates such as sodium bicarbonate and potassium bicarbonate; quaternary ammonium hydroxides such as tetramethylammonium hydroxide and choline; organic amines such as ethylamine, diethylamine, triethylamine, and hydroxyethylamine; ammonium carbonate; ammonium bicarbonate; and ammonia. One of these pH adjusters can be used alone or in combination of two or more. The amount of pH adjuster is set to the amount by which the pH of the etching solution composition becomes the desired pH.

[0045] Examples of chelating agents include aminocarboxylic acid chelating agents such as ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraaminehexaacetic acid, tetraethylenepentaamineheptaacetic acid, pentaethylenehexamineoctaacetic acid, hypozinotriacetic acid, and their alkali metal (preferably sodium) salts; phosphonic acid chelating agents such as hydroxyethylidene diphosphonic acid, hypozinotrimethylenephosphonic acid, phosphonobutane tricarboxylic acid, and their alkali metal (preferably sodium) salts; and dicarboxylic acid compounds such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, malic acid, tartaric acid, citric acid, their anhydrides, and their alkali metal (preferably sodium) salts, as well as mono- or dianhydrides formed by dehydration of di- or more carboxylic acid compounds. The content (concentration) of the chelating agent in the etching solution composition is preferably in the range of 0.01 to 40% by mass, more preferably in the range of 0.05 to 30% by mass.

[0046] Cationic and amphoteric surfactants can be used as surfactants. Examples of cationic surfactants include alkyl(alkenyl)trimethylammonium salts, dialkyl(alkenyl)dimethylammonium salts, alkyl(alkenyl)pyridinium salts, alkyl(alkenyl)dimethylbenzylammonium salts, alkyl(alkenyl)isoquinolineium salts, dialkyl(alkenyl)morpholineium salts, polyoxyethylene alkyl(alkenyl)amines, alkyl(alkenyl)amine salts, polyamine fatty acid derivatives, pentanol fatty acid derivatives, benzalkonium chloride, and benzyl chloride. Examples of amphoteric surfactants include carboxybetaine, sulfobetaine, phosphobetaine, amide amino acids, and imidazoline betaine-based surfactants. The surfactant content (concentration) in the etching solution composition is preferably in the range of 0.001 to 10% by mass.

[0047] As solvents, alcohol-based solvents, ketone-based solvents, and ether-based solvents can be used. Examples of alcohol-based solvents include methanol, ethanol, diethylene glycol, isopropanol, and 2-ethylhexanol. Examples of ketone-based solvents include methyl acetate, ethyl acetate, and propyl acetate. Examples of ether-based solvents include tetrahydrofuran and methyl cellosolve.

[0048] One embodiment of the etching method of the present invention includes the step of etching a copper-containing layer using the above-described composition (etching solution composition). Another embodiment of the substrate manufacturing method of the present invention includes the step of etching a copper-containing layer using the above-described etching solution composition. Both the etching method and the substrate manufacturing method of these embodiments are steps that can employ known general etching methods, except for using the above-described etching solution composition.

[0049] As the etched material, a copper-containing layer is preferably a layer comprising at least one selected from the group consisting of copper, copper-titanium alloys, copper-beryllium alloys, copper-nickel alloys, and copper-iron alloys. Among these, a layer comprising at least one copper alloy selected from the group consisting of copper-titanium alloys, copper-beryllium alloys, copper-nickel alloys, and copper-iron alloys is more suitable, and a copper-titanium alloy is even more suitable.

[0050] Specific etching methods include, for example, immersion etching and spraying. Etching conditions can be adjusted appropriately based on the composition of the etching solution and the etching method used. Furthermore, various known methods can be employed, such as intermittent etching, flow etching, and automatic control based on the etchant's redox potential, specific gravity, and acid concentration.

[0051] The etching conditions are not particularly limited and can be set arbitrarily according to the shape and film thickness of the object to be etched. For example, it is preferable to spray the etching solution composition at 0.01 to 0.20 MPa, and more preferably at 0.05 to 0.15 MPa. Furthermore, the etching temperature is preferably 10 to 50°C, and more preferably 20 to 50°C. The temperature of the etching solution composition may sometimes rise due to the heat of reaction; therefore, temperature control can be performed using known methods to maintain it within the above-mentioned temperature range as needed. The etching time is set to a time sufficient to sufficiently etch the object.

[0052] According to the etching method using the above-described etching solution composition and the substrate manufacturing method, it is possible to form fine patterns with high anisotropy. This enables the manufacture of a substrate having a copper-containing layer with fine patterns exhibiting high anisotropy. Therefore, in addition to printed circuit boards, it can be suitably used for reduction methods in packaging substrates requiring fine pitch, COF, and TAB applications.

[0053] As detailed above, one embodiment of the present invention may employ the following configuration.

[0054] [1] An etching solution composition for etching a copper-containing layer, comprising an aqueous solution containing (A) a compound of the above general formula (1), (B) at least one component selected from the group consisting of divalent copper ions and trivalent iron ions, and (C) an acid and water.

[0055] [2] According to the etching solution composition described in [1] above, the content of the aforementioned component (A) is 0.01 to 10% by mass, the content of the aforementioned component (B) is 1 to 35% by mass, and the content of the aforementioned component (C) is 1 to 35% by mass.

[0056] [3] According to the etching solution composition described in [1] or [2] above, wherein the aforementioned copper-containing layer is a copper alloy layer.

[0057] [4] According to the etching solution composition described in [3] above, wherein the aforementioned copper alloy is selected from at least one of the group consisting of copper-titanium alloy, copper-beryllium alloy, copper-nickel alloy and copper-iron alloy.

[0058] [5] The etching solution composition according to any one of [1] to [4] above, wherein the source of supply for the aforementioned component (B) is at least one selected from the group consisting of copper chloride (II) and ferric chloride (III).

[0059] [6] The etching solution composition according to any one of [1] to [5] above, wherein the mass ratio of the aforementioned (A) component to the total of the aforementioned (A) component and the aforementioned (B) component {(A) / ((A)+(B))} is 0.001 to 0.3.

[0060] [7] The etching solution composition according to any one of [1] to [6] above, wherein the mass ratio of the aforementioned (C) component to the total of the aforementioned (A) component and the aforementioned (B) component {(C) / ((A)+(B))} is 0.01 to 0.5.

[0061] [8] The etching solution composition according to any one of [1] to [7] above further contains (D) at least one specific gravity adjuster selected from the group consisting of calcium chloride, potassium chloride, magnesium chloride and sodium chloride.

[0062] [9] According to the etching solution composition described in [8] above, the content of the aforementioned component (D) is 0.1 to 15% by mass.

[0063]

[10] An etching method comprising the following steps: etching a copper-containing layer with an etching solution composition described in any of [1] to [9] above.

[0064]

[11] A method for manufacturing a substrate, comprising the following steps: etching a copper-containing layer with an etching solution composition described in any of [1] to [9] above.

[0065] Example

[0066] The present invention will now be described in detail with reference to embodiments and comparative examples, but the present invention is not limited thereto.

[0067] The following shows the (A) component used in the examples and comparative examples.

[0068] a-1: The compound represented by the above chemical formula No. 1

[0069] a-2: The compound represented by chemical formula No. 4 above.

[0070] a-3: The compound represented by the above chemical formula No. 5.

[0071] In addition, a-4 to a-6 as shown below were prepared as comparative components of component (A).

[0072] a-4: Comparison of compound 1

[0073] a-5: Comparison of compound 2

[0074] a-6: Comparison of compound 3

[0075]

[0076] The following shows the supply sources of component (B) used in the examples and comparative examples.

[0077] b-1: Copper(II) chloride

[0078] b-2: Ferric chloride (III)

[0079] The following shows the (C) component used in the examples and comparative examples.

[0080] c-1: Hydrochloric acid

[0081] c-2: Nitric acid

[0082] c-3: sulfuric acid

[0083] The following shows the (D) component used in the examples and comparative examples.

[0084] d-1: Sodium chloride

[0085] <Example 1 (Examples 1-1 to 1-11) and Comparative Example 1 (Comparative Examples 1-1 to 1-5)>

[0086] In a manner that makes up the composition shown in Table 1, component (A) or its comparative component, the supply source of component (B), component (C), component (D) and water are mixed to obtain etching solution compositions No. 1 to 16.

[0087] It should be noted that the types of component (B) shown in Table 1 represent the types of supply sources for component (B) (b-1 supplying divalent copper ions, b-2 supplying trivalent iron ions), and the content (mass%) of component (B) represents the content of component (B) (divalent copper ions, trivalent iron ions) supplied by the supply sources. In the etching solution composition, when the divalent copper ions supplied by b-1 (copper chloride (II)) are 10%, 16%, or 20% by mass, the content of copper chloride (II) is 21.2% by mass, 33.9% by mass, and 42.3% by mass, respectively. In addition, when the trivalent iron ions supplied by b-2 (ferric chloride (III)) are 16% by mass, the content of ferric chloride (III) is 46.5% by mass. The balance in the composition of the etching solution composition shown in Table 1 (the composition of component (A) or its comparative components, the supply source of component (B), component (C), and the total composition of component (D)) is water. In addition, the content of component (C) shown in Table 1 is based on acid content. For example, if component (C) is c-1, it is the content of hydrogen chloride.

[0088] Table 1

[0089]

[0090] <Example 2 (Examples 2-1 to 2-11) and Comparative Example 2 (Comparative Examples 2-1 to 2-5)>

[0091] A substrate is prepared on which a copper-titanium alloy layer with a thickness of 75 μm (titanium content 3% by mass) is laminated on a polyimide resin matrix (hereinafter sometimes referred to as "resin matrix"). A spacing of 120 μm (linewidth 70 μm, as per reference) is formed on the copper-titanium alloy layer of this substrate. Figure 1 A test substrate was fabricated using a photoresist layer with a linewidth of 6 μm and an opening of 50 μm. The fabricated test substrate was then subjected to wet etching using the prepared etching solution composition at a processing temperature of 45°C and a processing pressure of 0.10 MPa for 300 seconds. Afterwards, the photoresist pattern was removed using a stripping solution to form a pattern (fine lines).

[0092] <Evaluation>

[0093] A laser microscope was used to confirm the presence or absence of fine lines and residual film. Additionally, a focused ion beam processing observation device (JIB-4000, manufactured by Nippon Electronics Corporation) was used to process the cross-section of the fine lines, and the cross-section was observed using a scanning electron microscope (SEM). Then, based on the SEM image of the fine line cross-section, the width of the fine lines was measured. Specifically, a schematic cross-sectional view of the etched test substrate is shown. Figure 1 During the explanation, the width of the resist layer 2 side (width at the top of the fine line) 4, which became smaller than the width of the resin substrate 3 side (width at the bottom of the fine line) 5, in the cross-section of the etched copper alloy layer 1 (fine line of the copper-titanium alloy layer), was measured. The evaluation results and measurement results of (1) to (3) shown below are presented in Table 2. It should be noted that no residual film (residual of the etched part) means that sufficient etching can be carried out along the depth direction, and it is not easy for line breakage or short circuit to occur. In addition, the smaller the etch width of a single side, the more the side etching is suppressed.

[0094] (1) The presence or absence of fine lines

[0095] Cases where fine lines are formed are rated as "++", and cases where fine lines are not formed are rated as "--".

[0096] (2) Presence or absence of residual film

[0097] Cases with no residual film are rated as "++", and cases with residual film are rated as "--".

[0098] (3) Single-sided etching width

[0099] It is calculated using the following formula. The unit is "μm". Note that, in the absence of a fine line, the width of the upper part of the line cannot be measured; therefore, it is denoted as "cannot be measured".

[0100] "Single-sided etching width" = {"Resist linewidth" - "Measured width of the upper part of the fine line"} / 2

[0101] Table 2

[0102]

[0103] As shown in Table 2, in Examples 2-1 to 2-11, the etching width of a single side is 11.3 μm or less, demonstrating the ability to form fine patterns with excellent dimensional accuracy while suppressing residual film formation. In Examples 2-2 to 2-7 and 2-11, the etching width of a single side is 9.2 μm or less, demonstrating the ability to form fine patterns with even better dimensional accuracy while suppressing residual film formation. In particular, in Examples 2-2 and 2-5, the etching width of a single side is 8.9 μm or less, demonstrating the ability to form fine patterns with exceptionally excellent dimensional accuracy while suppressing residual film formation. In particular, in Example 2-2, the etching width of a single side is 8.8 μm, demonstrating the ability to form fine patterns with the best dimensional accuracy while suppressing residual film formation. On the other hand, in Comparative Examples 2-1 and 2-2, the etching width of a single side is 25.2 μm or more, and compared to Examples 2-1 to 2-11, patterns with poor dimensional accuracy are formed. Furthermore, in Comparative Examples 2-3 to 2-5, no pattern was formed. Based on the above results, according to one embodiment of the present invention, an etching solution composition that is less likely to produce residual film that could cause broken lines or short circuits, has a small unilateral etching width, and is capable of forming fine patterns with excellent dimensional accuracy with high anisotropy can be provided, along with an etching method and a method for manufacturing a substrate.

[0104] <Example 3 (Examples 3-1 to 3-3) and Comparative Example 3 (Comparative Examples 3-1 to 3-2)>

[0105] A substrate with a 75 μm thick copper-beryllium alloy layer (beryllium content 2% by mass) laminated on a polyimide resin matrix was prepared instead of the substrate with a copper-titanium alloy layer laminated on a resin matrix used in Example 2. Using this substrate, except that a photoresist layer was formed on the copper-beryllium alloy layer of the substrate according to the same method as in Example 2, and a test substrate was made. For this test substrate, wet etching was performed with the prepared etching solution composition, and the photoresist layer was removed to form a pattern (fine lines). In addition, according to the same method as in Example 2, the width 4 of the photoresist layer 2 side (width of the upper part of the fine lines) in the cross section of the etched copper alloy layer 1 (fine lines of the copper-beryllium alloy layer) was measured, and the evaluations shown in (1) to (3) above were performed. The evaluation results and measurement results are shown in Table 3.

[0106] Table 3

[0107]

[0108] <Example 4 (Examples 4-1 to 4-3) and Comparative Example 4 (Comparative Examples 4-1 to 4-2)>

[0109] A substrate with a 75 μm thick copper-nickel alloy layer (nickel content 3% by mass) laminated on a polyimide resin matrix was prepared instead of the substrate with a copper-titanium alloy layer laminated on a resin matrix used in Example 2. Using this substrate, except that a photoresist layer was formed on the copper-nickel alloy layer of the substrate according to the same method as in Example 2, and a test substrate was made. For this test substrate, wet etching was performed with the prepared etching solution composition, and the photoresist layer was removed to form a pattern (fine lines). In addition, according to the same method as in Example 2, the width (width of the upper part of the fine line) 4 of the photoresist layer 2 side in the cross section of the etched copper alloy layer 1 (fine lines of the copper-nickel alloy layer) was measured, and the evaluations shown in (1) to (3) above were performed. The evaluation results and measurement results are shown in Table 4.

[0110] Table 4

[0111]

[0112] <Example 5 (Examples 5-1 to 5-3) and Comparative Example 5 (Comparative Examples 5-1 to 5-2)>

[0113] A substrate with a 75 μm thick copper-iron alloy layer (iron content 3% by mass) laminated on a polyimide resin matrix was prepared instead of the substrate with a copper-titanium alloy layer laminated on a resin matrix used in Example 2. Using this substrate, except that a photoresist layer was formed on the copper-iron alloy layer of the substrate according to the same method as in Example 2, and a test substrate was made. For this test substrate, wet etching was performed with the prepared etching solution composition, and the photoresist layer was removed to form a pattern (fine lines). In addition, according to the same method as in Example 2, the width (width of the upper part of the fine line) 4 of the photoresist layer 2 side in the cross section of the etched copper alloy layer 1 (fine lines of the copper-iron alloy layer) was measured, and the evaluations shown in (1) to (3) above were performed. The evaluation results and measurement results are shown in Table 5.

[0114] Table 5

[0115]

[0116] Explanation of reference numerals in the attached figures

[0117] 1: Copper alloy layer

[0118] 2: Anti-corrosion layer

[0119] 3: Resin matrix

[0120] 4: Width of the upper part of the thin line

[0121] 5: Width of the lower part of the thin line

[0122] 6: Line width of the anti-corrosion layer

Claims

1. An etching solution composition for etching a copper-containing layer, comprising (A) a compound of general formula (1), (B) at least one component selected from the group consisting of divalent copper ions and trivalent iron ions, and (C) an acid and water, In the general formula (1), R 1 and R 2 Each can independently represent a hydrogen atom, amino group, thiol group, phenyl group, or carboxyl group, among which, R 1 and R 2 When one of them is a hydrogen atom, the other is a thiol group, phenyl group, or carboxyl group.

2. The etching solution composition according to claim 1, wherein, The content of component (A) is 0.01 to 10% by mass, the content of component (B) is 1 to 35% by mass, and the content of component (C) is 1 to 35% by mass.

3. The etching solution composition according to claim 1 or 2, wherein, The copper-containing layer is a copper alloy layer.

4. The etching solution composition according to claim 3, wherein, The copper alloy is selected from at least one of the following groups: copper-titanium alloy, copper-beryllium alloy, copper-nickel alloy, and copper-iron alloy.

5. The etching solution composition according to claim 1 or 2, wherein, The source of supply for component (B) is at least one selected from the group consisting of copper chloride (II) and ferric chloride (III).

6. The etching solution composition according to claim 1 or 2, wherein, The mass ratio of component (A) to the total mass of component (B) {(A) / ((A)+(B))} is 0.001 to 0.

3.

7. The etching solution composition according to claim 1 or 2, wherein, The mass ratio of component (C) to the total mass of components (A) and (B) {(C) / ((A)+(B))} is 0.01 to 0.

5.

8. The etching solution composition according to claim 1 or 2, further comprising (D) at least one specific gravity adjuster selected from the group consisting of calcium chloride, potassium chloride, magnesium chloride and sodium chloride.

9. The etching solution composition according to claim 8, wherein, The content of component (D) is 0.1-15% by mass.

10. An etching method comprising the step of etching a copper-containing layer with the etching solution composition of claim 1 or 2.

11. A method for manufacturing a substrate, comprising the step of etching a copper-containing layer with the etching solution composition of claim 1 or 2.

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