JP2020128574A - Composition and etching method - Google Patents

Abstract

To provide a composition useful in etching of a metal layer, such as a copper based layer, which can form a fine pattern excellent in dimensional accuracy with high linearity while inhibiting generation of a residual film.SOLUTION: The composition is an aqueous solution comprising: (A) 0.1-25 mass% of at least one component selected from cupric and ferric ions; (B) 0.1-30 mass% of chloride ions; (C) 0.01-10 mass% of a compound represented by the specified general formula (1) having a number-average molecular weight of 550-1,400; (D) 0.01-10 mass% of a compound represented by the specified general formula (2); and water.SELECTED DRAWING: None

Description

The present invention relates to a composition containing a compound having a specific structure, and an etching method using the composition.

Circuit formation methods for printed circuit boards, semiconductor package boards, etc. include an additive method in which a circuit pattern is later attached to the board and a subtractive method (etching method) in which unnecessary portions are removed from the metal foil on the board to form the circuit pattern. Are known. At present, a subtractive method (etching method), which has a low manufacturing cost, is generally adopted for manufacturing a printed circuit board. With the recent miniaturization and high performance of electronic devices, development of an etching solution capable of forming a highly linear fine pattern on a printed circuit board is under way.

For example, Patent Document 1 discloses an etching solution for copper or a copper alloy containing iron chloride, oxalic acid, and ethylenediaminetetrapolyoxyethylenepolyoxypropylene as the etching solution. Further, Patent Document 2 discloses an etching solution for a copper-containing material containing ferric chloride, a glycol ether compound, ethylenediaminetetrapolyoxyethylenepolyoxypropylene, phosphoric acid, and hydrochloric acid. Further, Patent Document 3 discloses a microetching agent containing cupric oxide, formic acid, sodium chloride, a polymer and an acetylene glycol polyoxyethylene adduct.

JP 2012-107286 A JP, 2009-167459, A International Publication No. 2013/187537

However, when etching is performed using the etching solution disclosed in the above-mentioned patent documents, it is difficult to form a fine pattern having a high linearity and a desired dimensional accuracy, or a residue that causes a disconnection or a short circuit. There is a problem that a film is easily generated.

Therefore, the present invention provides a composition having high linearity and capable of forming a fine pattern excellent in dimensional accuracy while suppressing the formation of a residual film, and a composition useful for etching a metal layer such as a copper-based layer. It is the one to be provided. The present invention also aims to provide an etching method using the above composition.

As a result of intensive studies to obtain the above composition, the present inventors have found that a composition containing a specific component can solve the above problems, and have reached the present invention.

That is, according to the present invention, (A) at least one component selected from cupric ion and ferric ion 0.1 to 25 mass%; (B) chloride ion 0.1 to 30 mass% (C) 0.01 to 10% by mass of a compound represented by the following general formula (1) and having a number average molecular weight of 550 to 1,400; (D) a compound 0.01 represented by the following general formula (2) 10% by mass; and a composition that is an aqueous solution containing water.

（前記一般式（１）中、Ｒ^１は、単結合、又は炭素原子数１〜４の直鎖状若しくは分岐状のアルカンジイル基を表し、Ｒ^２及びＲ^３は、それぞれ独立に、炭素原子数１〜４の直鎖状又は分岐状のアルカンジイル基を表し、Ｒ^４及びＲ^５は、それぞれ独立に、水素原子、又は炭素原子数１〜４の直鎖状若しくは分岐状のアルキル基を表し、ｎは、それぞれ独立に、前記一般式（１）で表される化合物の数平均分子量が５５０〜１，４００となる数を表す。）

(In the general formula (1), R ¹ represents a single bond or a linear or branched alkanediyl group having 1 to 4 carbon atoms, and R ² and R ³ are each independently a carbon atom. Represents a linear or branched alkanediyl group having a number of 1 to ^4, and R ⁴ and R ⁵ each independently represent a hydrogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms. In the formula, n independently represents the number at which the compound represented by the general formula (1) has a number average molecular weight of 550 to 1,400.)

（前記一般式（２）中、Ｒ^６〜Ｒ^９は、それぞれ独立に、炭素原子数１〜５の直鎖状又は分岐状のアルキル基を表し、Ｒ^１０及びＲ^１１は、それぞれ独立に、炭素原子数２〜４の直鎖状又は分岐状のアルカンジイル基を表し、ｐ及びｑは、ｐとｑの合計が１５〜４０となる１以上の数を表す。）

(In the general formula (2), R ^{6 to} R ⁹ each independently represent a linear or branched alkyl group having 1 to 5 carbon atoms, and R ¹⁰ and R ¹¹ are each independently It represents a linear or branched alkanediyl group having 2 to 4 carbon atoms, and p and q represent one or more numbers such that the sum of p and q is 15 to 40.)

Further, according to the present invention, there is provided an etching method including a step of etching using the above composition.

According to the present invention, a composition having high linearity and capable of forming a fine pattern excellent in dimensional accuracy while suppressing the generation of a residual film, and a composition useful for etching a metal layer such as a copper-based layer is provided. Can be provided. Further, according to the present invention, it is possible to provide an etching method using the above composition.

It is sectional drawing which shows the test substrate after etching typically.

Hereinafter, embodiments of the present invention will be described in detail. The composition of one embodiment of the present invention (hereinafter, sometimes referred to as “the present composition”) is (A) at least one component selected from cupric ion and ferric ion (hereinafter , (Also referred to as “(A) component”); (B) chloride ion (hereinafter, also referred to as “(B) component”); (C) compound represented by general formula (1) (hereinafter, “( (C) component"); (D) compound represented by the general formula (2) (hereinafter, also referred to as "(D) component"); and water as an essential component. The present composition is suitable as an etching solution composition used for etching a metal layer such as a copper-based layer. Examples of the copper-based layer include a layer containing a copper alloy such as a silver-copper alloy and an aluminum-copper alloy; and copper. Among them, the present composition is suitable as an etching liquid composition used for etching a copper-based layer containing copper.

As the component (A), cupric ion and ferric ion are used alone or in combination. By incorporating a copper (II) compound, cupric ion can be contained in the composition. That is, a copper(II) compound can be used as a supply source of cupric ions. In addition, ferric ion can be contained in the composition by blending an iron (III) compound. That is, an iron (III) compound can be used as a source of ferric ion.

Examples of the copper (II) compound include copper (II) chloride, copper (II) bromide, copper (II) sulfate, and copper (II) hydroxide. Examples of the iron (III) compound include iron (III) chloride, iron (III) bromide, iron (III) iodide, iron (III) sulfate, iron (III) nitrate, and iron (III) acetate. Can be mentioned. Among these compounds, copper(II) chloride and iron(III) chloride are preferable, and copper(II) chloride is particularly preferable. These compounds may be used alone or in combination of two or more.

The concentration of the component (A) in the composition is 0.1 to 25% by mass, preferably 0.5 to 23% by mass, and more preferably 1 to 20% by mass. For example, when the present composition is used as an etching solution composition, the concentration of the component (A) can be appropriately adjusted according to the thickness and width of the object to be etched. The component (A) concentration means the concentration of cupric ion or the concentration of ferric ion when cupric ion or ferric ion is used alone. When the cupric ion and the ferric ion are used in combination (mixed), the sum of the concentration of the cupric ion and the concentration of the ferric ion is meant. For example, when the copper (II) chloride content is 10% by mass, the concentration of the component (A) is about 4.7% by mass. When the content of copper (II) chloride is 10% by mass and the content of iron (III) chloride is 10% by mass, the concentration of the component (A) is about 8.2% by mass. When the cupric ion and ferric ion are used in combination (mixed), the concentration of ferric ion is preferably less than 5% by mass.

As a supply source of the component (B), hydrogen chloride, sodium chloride, calcium chloride, potassium chloride, barium chloride, ammonium chloride, iron (III) chloride, copper (II) chloride, manganese (II) chloride, cobalt (II) chloride , Cerium (III) chloride, zinc (II) chloride and the like can be used. In particular, when the present composition is used as an etching solution composition, hydrogen chloride, iron (III) chloride, copper (II) chloride are used because the etching rate is easily controlled and the shape of the wiring pattern is easily controlled. Is preferred, and hydrogen chloride is more preferred.

The concentration of the component (B) in the composition is 0.1 to 30% by mass, preferably 0.5 to 28% by mass, more preferably 1 to 25% by mass. For example, when the present composition is used as an etching solution composition, the concentration of the component (B) can be appropriately adjusted according to the thickness and width of the object to be etched. When the concentration of the component (B) is less than 0.1% by mass, the etching rate may be insufficient when the composition is used as an etching solution composition. On the other hand, even if the concentration of the component (B) exceeds 30% by mass, it is difficult to further improve the etching rate, and on the contrary, problems such as corrosion of the device members may easily occur.

In the present composition, the mass ratio of the component (B) to the component (A) is preferably (B)/(A)=0.5 to 2, and more preferably 0.6 to 1.8. , Particularly preferably 0.65 to 1.7, and most preferably 0.7 to 1.4. When the value of (B)/(A) is 2 or less, it becomes easy to form a fine wiring pattern having excellent dimensional accuracy when the present composition is used as an etching solution composition. On the other hand, when the value of (B)/(A) is 0.5 or more, the etching rate tends to be increased when the present composition is used as an etching solution composition.

The component (C) is a compound represented by the following general formula (1) and having a number average molecular weight of 550 to 1,400.

（一般式（１）中、Ｒ^１は、単結合、又は炭素原子数１〜４の直鎖状若しくは分岐状のアルカンジイル基を表し、Ｒ^２及びＲ^３は、それぞれ独立に、炭素原子数１〜４の直鎖状又は分岐状のアルカンジイル基を表し、Ｒ^４及びＲ^５は、それぞれ独立に、水素原子、又は炭素原子数１〜４の直鎖状若しくは分岐状のアルキル基を表し、ｎは、それぞれ独立に、一般式（１）で表される化合物の数平均分子量が５５０〜１，４００となる数を表す。）

(In the general formula (1), R ¹ represents a single bond or a linear or branched alkanediyl group having 1 to 4 carbon atoms, and R ² and R ³ each independently represent the number of carbon atoms. 1 to 4 represents a linear or branched alkanediyl group, and R ⁴ and R ⁵ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms. , N each independently represent a number such that the compound represented by the general formula (1) has a number average molecular weight of 550 to 1,400.)

In the general formula (1), R ¹ represents a single bond or a linear or branched alkanediyl group having 1 to 4 carbon atoms. Further, R ₂ and R ₃ each independently represent a linear or branched alkanediyl group having 1 to 4 carbon atoms. Examples of the linear or branched alkanediyl group having 1 to 4 carbon atoms represented by R ¹ , R ² and R ³ include a methylene group, an ethylene group, a propylene group, a methylethylene group, a butylene group and ethyl. Examples thereof include an ethylene group, a 1-methylpropylene group, and a 2-methylpropylene group. The alkanediyl group may be only one kind or a combination of two or more kinds. When the present composition is used as an etching solution composition, R ¹ is preferably an ethylene group, and R ² and R ³ are preferably a methylethylene group, because the etching rate is easily controlled and side etching is easily suppressed.

In the general formula (1), R ⁴ and R ⁵ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms. Examples of the linear or branched alkyl group having 1 to 4 carbon atoms represented by R ⁴ and R ⁵ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, and a secondary butyl group. , A tertiary butyl group can be mentioned. When the present composition is used as an etching solution composition, hydrogen atoms are preferable for R ⁴ and R ⁵ because the etching rate is easily controlled and side etching is easily suppressed.

In the general formula (1), n's each independently represent a number such that the compound represented by the general formula (1) has a number average molecular weight of 550 to 1,400. When the present composition is used as an etching solution composition, n is preferably a number having a number average molecular weight of 650 to 1,300, because the etching rate is easily controlled and side etching is easily suppressed. It is more preferable that the number is 750 to 1,200.

Specific preferred examples of the compound represented by the general formula (1) include the following formula No. 1-No. The compound represented by 36 can be mentioned. The following formula No. 1-No. 36, "Me" represents a methyl group, "Et" represents an ethyl group, and "iPr" represents an isopropyl group. Further, n is independent of No. 1-No. The number average molecular weight of the compound represented by 36 is 550 to 1,400.

The method for producing the component (C) is not particularly limited, and it can be produced by applying a well-known reaction. For example, the above formula No. The compound represented by 17 can be produced by the reaction represented by the following formula (3) using ethylenediamine and propylene oxide as raw materials. “Me” in the following formula (3) represents a methyl group.

The concentration of the component (C) in the composition is 0.01 to 10% by mass, preferably 0.05 to 8% by mass, and more preferably 0.1 to 5% by mass. If the concentration of the component (C) is less than 0.01% by mass, the desired effect due to the addition of the component (C) may not be obtained. On the other hand, when the concentration of the component (C) is more than 10% by mass, when the present composition is used as an etching solution composition, the etching rate is likely to decrease. In addition, the etching solution composition may easily penetrate into the interface between the metal layer such as a copper-based layer and the resist, which may cause defects in the pattern shape.

In this composition, the mass ratio of the component (C) to the sum of the components (A) and (B) is preferably (C)/((A)+(B))=0.005 to 0.2. Yes, more preferably 0.01 to 0.15, particularly preferably 0.02 to 0.1, and most preferably 0.03 to 0.05. When the value of (C)/((A)+(B)) is 0.2 or less, it becomes easy to increase the etching rate when the present composition is used as an etching solution composition. On the other hand, when the value of (C)/((A)+(B)) is 0.005 or more, it becomes easy to obtain a desired effect by blending the component (C).

The component (D) is a compound represented by the following general formula (2).

（一般式中、Ｒ^６〜Ｒ^９は、それぞれ独立に、炭素原子数１〜５の直鎖状又は分岐状のアルキル基を表し、Ｒ^１０及びＲ^１１は、それぞれ独立に、炭素原子数２〜４の直鎖状又は分岐状のアルカンジイル基を表し、ｐ及びｑは、ｐとｑの合計が１５〜４０となる１以上の数を表す。）

(In the general formula, R ^{6 to} R ⁹ each independently represent a linear or branched alkyl group having 1 to 5 carbon atoms, and R ¹⁰ and R ¹¹ each independently represent 2 carbon atoms. ~4 represents a linear or branched alkanediyl group, and p and q represent a number of 1 or more such that the sum of p and q is 15 to 40.)

In the general formula (2), R ^{6 to} R ⁹ each independently represent a linear or branched alkyl group having 1 to 5 carbon atoms. Examples of the linear or branched alkyl group having 1 to 5 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, secondary butyl group, tertiary butyl group, pentyl group, An isopentyl group and a neopentyl group can be mentioned. It is preferable that R ⁶ and R ⁷ are isobutyl groups, and R ⁸ and R ⁹ are methyl groups, from the viewpoint that the linearity of the fine line is improved when the present composition is used as an etching solution composition. ..

In the general formula (2), R ¹⁰ and R ¹¹ represent a linear or branched alkanediyl group having 2 to 4 carbon atoms. Examples of the linear or branched alkanediyl group having 2 to 4 carbon atoms include ethylene group, propylene group, methylethylene group, butylene group, ethylethylene group, 1-methylpropylene group, and 2-methylpropylene group. Can be mentioned. From the viewpoint that the linearity of the fine line is good when the present composition is used as an etching solution composition, ethylene groups are preferable for R ¹⁰ and R ¹¹ .

In the general formula (2), p and q represent a number of 1 or more, and the sum of p and q is 15 to 40. The sum of p and q is preferably 20 to 35, more preferably 25 to 30, from the viewpoint that the linearity of the fine line is improved when the composition is used as an etching solution composition.

Specific preferred examples of the compound represented by the general formula (2) include the following formula No. 37-No. The compound represented by 78 can be mentioned. The following formula No. 37-No. 78, "Me" represents a methyl group, "Et" represents an ethyl group, "Pr" represents a propyl group, "iPr" represents an isopropyl group, "Bu" represents a butyl group, and "iBu". "Represents an isobutyl group.

The component (D) can be manufactured according to a known method, or a commercially available product may be used. Examples of commercially available products include Surfynol 485 (manufactured by Nissin Chemical Industry Co., Ltd.) and acetylenol E200 (manufactured by Kawaken Fine Chemicals Co., Ltd.).

The concentration of the component (D) in the composition is 0.01 to 10% by mass, preferably 0.03 to 5% by mass, and more preferably 0.05 to 1% by mass. If the concentration of the component (D) is less than 0.01% by mass, it is difficult to form a highly linear pattern even when the composition is used as an etching solution composition, and the concentration of the component (D) is 10% by mass. Even if it exceeds, the effect due to the addition of the component (D) is difficult to improve.

In the present composition, the mass ratio of the component (D) to the sum of the component (A), the component (B) and the component (C) is preferably (D)/((A)+(B)+(C)). = 0.0005 to 0.02, more preferably 0.001 to 0.015, particularly preferably 0.002 to 0.01, and most preferably 0.003 to 0.005. When the value of (D)/((A)+(B)+(C)) is 0.02 or less, the component (D) is easily dissolved. On the other hand, when the value of (D)/((A)+(B)+(C)) is 0.0005 or more, it becomes easy to obtain the desired effect by blending the component (D).

The composition is an aqueous solution containing water as an essential component, in which each component is dissolved in water. As the water, ion-exchanged water, pure water, ultrapure water, or other water from which ionic substances and impurities have been removed can be used.

This composition is preferably used as an etching agent (etching solution) for etching a metal layer such as a copper-based layer, an additive for an electroless plating solution, an additive for metal electrolytic refining, an agricultural chemical, and an insecticide. You can Especially, it is suitable as an etching agent composition used for etching a metal layer.

When the present composition is an etching solution composition, the effects of the present invention can be obtained in the etching solution composition as components other than the component (A), the component (B), the component (C), the component (D) and water. Well-known additives and solvents can be blended within a range that does not impair the above. As the additive, a stabilizer for the etching liquid composition, a solubilizer for each component, a pH adjuster, a specific gravity adjuster, a viscosity adjuster, a wettability improver, a chelating agent, an oxidizing agent, a reducing agent, a surfactant. Etc. can be mentioned. The concentration of these additives may be in the range of 0.001 to 50% by mass, respectively.

Examples of the pH adjuster include inorganic acids such as sulfuric acid and nitric acid, and salts thereof; water-soluble organic acids and salts thereof; 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; carbonates of alkali metals such as lithium carbonate, sodium carbonate and potassium carbonate; carbonates of alkali metals such as sodium hydrogen carbonate and potassium hydrogen carbonate Hydrogen salts; quaternary ammonium hydroxides such as tetramethylammonium hydroxide and choline; organic amines such as ethylamine, diethylamine, triethylamine and hydroxyethylamine; ammonium carbonate; ammonium hydrogencarbonate; ammonia; and the like. These pH adjusters can be used alone or in combination of two or more. The content of the pH adjustor may be an amount such that the pH of the etching solution composition becomes a desired pH.

Examples of the chelating agent include ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraminehexaacetic acid, tetraethylenepentamineheptaacetic acid, pentaethylenehexamineoctaacetic acid, nitrilotriacetic acid, and alkali metal (preferably sodium) salts thereof. Aminocarboxylic acid-based chelating agents; phosphonic acid-based chelating agents such as hydroxyethylidene diphosphonic acid, nitrilotrismethylenephosphonic acid, phosphonobutane tricarboxylic acid, and their alkali metal (preferably sodium) salts; oxalic acid, malonic acid Dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, fumaric acid, malic acid, tartaric acid, citric acid, their anhydrides, and their alkali metal (preferably sodium) salts. An acid compound, a monoanhydride or a dianhydride obtained by dehydrating a carboxylic acid compound having a valence of 2 or more can be mentioned. The concentration of the chelating agent in the etching solution composition is generally in the range of 0.01 to 40% by mass, preferably 0.05 to 30% by mass.

As the surfactant, a cationic surfactant and an amphoteric surfactant can be used. Examples of the cationic surfactant include alkyl(alkenyl)trimethylammonium salt, dialkyl(alkenyl)dimethylammonium salt, alkyl(alkenyl)quaternary ammonium salt, alkyl(alkenyl)pyridinium salt, alkyl(alkenyl)dimethylbenzylammonium salt. , Alkyl (alkenyl) isoquinolinium salts, dialkyl (alkenyl) morphonium salts, polyoxyethylene alkyl (alkenyl) amines, alkyl (alkenyl) amine salts, polyamine fatty acid derivatives, amyl alcohol fatty acid derivatives, benzalkonium chloride, benzethonium chloride, and Examples thereof include a mono- or dialkyl(alkenyl)quaternary ammonium salt containing an ether group, an ester group, or an amide group. Examples of the amphoteric surfactant include carboxybetaine, sulfobetaine, phosphobetaine, amide amino acid, and imidazolinium betaine surfactant. The concentration of the surfactant in the etching liquid composition is generally in the range of 0.001 to 10% by mass.

As the solvent, an alcohol solvent, a ketone solvent, an ether solvent, or the like can be used. Examples of alcohol solvents include methanol, ethanol, diethylene glycol, isopropyl alcohol, and 2-ethylhexanol. Examples of the ketone solvent include methyl acetate, ethyl acetate, propyl acetate and the like. Examples of the ether-based solvent include tetrahydrofuran and methyl cellosolve.

An etching method according to an embodiment of the present invention includes a step of etching using the present composition (etching solution composition) described above. This etching method can employ the steps of well-known general etching methods, except that the above-mentioned etching liquid composition is used. Among the metal layers, a copper-based layer is particularly preferable as the object to be etched. Examples of the copper-based layer include a layer containing a copper alloy such as a silver-copper alloy and an aluminum-copper alloy; and copper. Of these, copper is particularly preferable. As a specific etching method, for example, a dipping method or a spray method can be adopted. The etching conditions may also be appropriately adjusted according to the composition of the etching solution composition used and the etching method. Further, various well-known methods such as a batch method, a flow method, an auto-control method based on the redox potential and specific gravity of an etchant, and an acid concentration may be adopted.

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, the etching solution composition is preferably sprayed at 0.01 to 0.2 MPa, more preferably 0.01 to 0.1 MPa. The etching temperature is preferably 10 to 50°C, more preferably 20 to 50°C. Since the temperature of the etching solution composition may rise due to the heat of reaction, the temperature may be controlled by known means so that it is maintained within the above temperature range, if necessary. The etching time may be a time that can sufficiently etch the object to be etched. For example, when an object to be etched having a film thickness of about 1 μm, a line width of about 10 μm, and an opening of about 100 μm is etched in the above temperature range, the etching time may be set to about 10 to 300 seconds.

According to the etching method using the above etching solution composition, it is possible to form a fine pattern having high linearity while suppressing the generation of a residual film. Therefore, in addition to the printed wiring board, it can be suitably used for a substrate for a package that requires a fine pitch having high linearity, a subtractive method for COF and TAB applications.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Table 1 shows the number average molecular weights of the component (C) and comparative components used in Examples and Comparative Examples. Both c-1 and c-2 which are the (C) components in Table 1 have the above formula No. A compound represented by the formula No. 17: N in 17 is the above formula No. The compound represented by 17 has the number average molecular weight of the value shown in Table 1. In addition, both of the comparative components of the component (C), c-3 and c-4, are represented by the above formula No. N in 17 is the above formula No. 17 except that the number average molecular weight of the compound represented by 17 is the number shown in Table 1. A compound represented by the same formula as 17.

Table 2 shows the sum of p and q in the component (D) used in Examples and Comparative Examples and the comparative component. All of the components (D-1) and (d-2) as the component (D) in Table 2 are represented by the above formula No. The compound represented by 42. Further, d-3 and d-4, which are comparison components of the component (D), are both the above formula No. 42, except that p and q in 42 are numbers such that the sum of p and q has the values shown in Table 2. A compound represented by the same formula as 42.

As comparative components of the other component (D), d-5 and d-6 shown below were prepared.
d-5: Comparative compound 1
d-6: Comparative compound 2

The structural formulas of Comparative Compounds 1 and 2 are shown below.

(Example 1 and Comparative Example 1)
To obtain the composition shown in Table 3, copper (II) chloride, hydrochloric acid, the component (C) or its comparative component, the component (D) or its comparative component, and water were mixed to prepare an etching liquid composition No. 1-18 were obtained. The balance of the composition of the etching solution composition shown in Table 3 is water.

(Example 2 and Comparative Example 2)
A substrate was prepared by laminating a copper foil having a thickness of 8 μm on a resin substrate. A photoresist having a pattern with a line width of 11 μm and an opening of 5 μm was formed on the copper foil of this substrate to prepare a test substrate. Using the prepared etching solution composition, the prepared test substrate was wet-etched by spraying just etching time (50 to 95 seconds) under the conditions of a processing temperature of 45° C. and a processing pressure of 0.05 MPa. The just etching time means the time until the width of the lower part of the thin line becomes 8 μm, which is calculated from the etching rate. Then, the resist pattern was removed using a stripping solution to form a pattern (thin line).

The thin lines thus formed were evaluated in (1) to (4) below. The evaluation results are shown in Table 4. The absence of the residual film (remaining portion of the etched portion) means that disconnection or short circuit is unlikely to occur. Further, the smaller the one-side side etching width, the more the side etching is suppressed. A cross-sectional view schematically showing the test substrate after etching is shown in FIG.

(1) Presence or absence of thin line formation A cross section was observed using a laser microscope and measured. The case where the thin line was formed was defined as “++”, and the case where the thin line was not formed was defined as “−−”.
(2) Presence or absence of residual film It was measured by observing a cross section using a laser microscope. The case where there was no residual film was designated as "++", and the case where there was a residual film was designated as "-".
(3) Linearity of fine line Observe the shape of the fine line by using a laser microscope. If the blur of the fine line is less than 0.3 μm, “++++”, and if the blur of the fine line is 0.3 μm or more and less than 0.5 μm "++", those having a thickness of 0.5 μm or more and less than 1.0 μm were designated as “++”, those having a thickness of 1.0 μm or more and less than 1.5 μm were designated as “−−”, and those having a thickness of 1.5 μm or more were designated as “−−−”. However, if there is a residual film, the blur of the thin line cannot be measured, and thus it is set to "not measurable".
(4) Side etch width on one side Calculated from the following formula. The unit is “μm”. However, when the thin line was not formed, the width of the upper part of the thin line could not be measured, and thus it was set as “not measurable”.
"One-side side etch width" = {"resist line width"-"measured value of width of thin line upper part"/2

As shown in Table 4, in Examples 2-1 to 2-10, it is understood that a pattern having high linearity and a small side etch width on one side could be formed while suppressing generation of a residual film. In particular, in Examples 2-1 to 2-7, it was found that a pattern with higher linearity could be formed, and particularly in Examples 2-1 to 2-4, a pattern with particularly high linearity could be formed. I understand that On the other hand, in Comparative Examples 2-1 and 2-3 to 2-7, it can be seen that a pattern having low linearity and a large side etch width was formed. Among them, it can be seen that in Comparative Example 2-4, a pattern having lower linearity was formed. Further, in Comparative Example 2-8, no pattern was formed, and in Comparative Example 2-2, the component (D) was not dissolved in the first place and the copper foil could not be etched. From the above results, according to the present embodiment, a composition for etching that is less likely to cause a residual film that causes a disconnection or a short circuit and can form a fine pattern having desired linearity and dimensional accuracy. An object and an etching method can be provided.

1: Copper foil 2: Resist 3: Resin base 4: Width above thin line 5: Width below thin line 6: Resist line width

Claims (7)

(A) 0.1 to 25% by mass of at least one component selected from cupric ion and ferric ion;
(B) 0.1 to 30% by mass of chloride ion;
(C) 0.01 to 10% by mass of a compound represented by the following general formula (1) and having a number average molecular weight of 550 to 1,400;
(D) 0.01 to 10 mass% of a compound represented by the following general formula (2):
And a composition which is an aqueous solution containing water.

(In the general formula (1), R ¹ represents a single bond or a linear or branched alkanediyl group having 1 to 4 carbon atoms, and R ² and R ³ are each independently a carbon atom. Represents a linear or branched alkanediyl group having a number of 1 to ^4, and R ⁴ and R ⁵ each independently represent a hydrogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms. In the formula, n independently represents the number at which the compound represented by the general formula (1) has a number average molecular weight of 550 to 1,400.)

(In the general formula (2), R ^{6 to} R ⁹ each independently represent a linear or branched alkyl group having 1 to 5 carbon atoms, and R ¹⁰ and R ¹¹ are each independently It represents a linear or branched alkanediyl group having 2 to 4 carbon atoms, and p and q represent one or more numbers such that the sum of p and q is 15 to 40.) The composition according to claim 1, wherein the mass ratio of the component (B) to the component (A) is (B)/(A)=0.5 to 2. The mass ratio of the (C) component to the sum of the (A) component and the (B) component is (C)/((A)+(B))=0.005 to 0.2. The composition according to 1 or 2. The mass ratio of the component (D) to the sum of the component (A), the component (B) and the component (C) is (D)/((A)+(B)+(C))=0. The composition according to any one of claims 1 to 3, which is 0005 to 0.02. The composition according to any one of claims 1 to 4, which is an etching solution composition used for etching a metal layer. The composition according to claim 5, wherein the metal layer is a copper-based layer. An etching method comprising a step of etching using the composition according to claim 1.

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