Copper etching liquid composition and preparation method thereof

Abstract

The invention provides a copper etching liquid composition and a preparation method thereof, and relates to the technical field of wet etching. The copper etching liquid comprises the following raw materials in percentage by mass: 8-20% of hydrogen peroxide, 0.5-2.5% of inorganic matters, 0.05-2% of a corrosion inhibitor, 0.5-5% of a scavenging agent, 0.5-5% of a complexing agent and the balance of deionized water, the inorganic matter is selected from inorganic acid and / or inorganic salt. The copper etching liquid composition provided by the invention can significantly slow down the decomposition of hydrogen peroxide in the etching process, thereby maintaining excellent etching performance. Through accurate regulation and control, the copper etching liquid composition not only ensures ideal etching taper angle and CD loss variation, but also avoids generation of tail, and ensures that the surface of a substrate is clean and free of residues.

Description

Technical Field

[0001] The invention relates to the technical field of wet etching, and in particular to a copper etching liquid composition and a preparation method thereof. Background Art

[0002] Copper metal is widely used in the manufacture of printed circuit boards (PCBs) or printed wiring boards (PWBs) due to its good conductivity and ductility. In this application, etching the metal layer is one of the key steps, and the etching methods are mainly divided into dry etching and wet etching. Compared with dry etching, wet etching has become the preferred method in the industry due to its advantages such as low cost, high reliability, high productivity and superior selectivity, and has made the development of copper etching solution a hot topic in recent years.

[0003] In order to improve the adhesion of metallic copper on the glass substrate, a layer of molybdenum or molybdenum-niobium alloy is usually plated on the bottom layer to enhance its adhesion. In the PCB / PWB production process, an excellent copper etching solution needs to meet the appropriate etching angle and critical dimension loss (CD Loss), while ensuring no metal residue and avoiding the formation of tailing, etc., to ensure the smooth progress of subsequent processes. The hydrogen peroxide-based copper etching solution currently common on the market will catalyze the decomposition of hydrogen peroxide as the copper ion content in the solution increases during the etching process, thereby shortening the etching life of the solution. The reaction mechanism of this catalytic effect may be: copper ions coordinate with hydrogen peroxide to form a copper-hydrogen peroxide complex. This complex, as an intermediate, can undergo a redox reaction with copper ions to form an oxidized copper ion and a hydroxyl radical. The latter will further promote the decomposition of hydrogen peroxide to form water and another hydroxyl radical. This process can be repeated continuously to form a free radical chain reaction, and finally produce oxygen and water. In addition, in patent CN 116970952 A, a compound that can ionize fluoride ions is added to the copper etching solution to assist etching. However, the addition of fluoride ions will corrode the glass substrate, thereby causing safety problems such as leakage of the substrate in the later stage.

[0004] Therefore, it is urgent to develop a new copper etching solution that does not corrode the glass substrate while ensuring the stable etching performance and long service life of the hydrogen peroxide copper etching solution. Summary of the invention

[0005] In view of this, the present invention provides a copper etching solution composition and a preparation method thereof. The composition ensures its etching performance by adding a hydroxyl radical scavenger and a complexing agent. On the one hand, the scavenger removes hydroxyl radicals to slow down the consumption of hydrogen peroxide, and on the other hand, the complexing agent complexes copper ions to reduce the content of copper ions in the solution and slow down the catalytic effect on hydrogen peroxide, thereby achieving the purpose of extending the service life of the etching solution.

[0006] In a first aspect, the present invention provides a copper etching solution composition, which comprises the following raw materials, by mass percentage: 8-20% of hydrogen peroxide (mass concentration is 30%, also known as "hydrogen peroxide"), 0.5-2.5% of inorganic matter, 0.05-2% of corrosion inhibitor, 0.5-5% of scavenger and 0.5-5% of complexing agent, and the balance is deionized water; the inorganic matter is selected from inorganic acid and / or inorganic salt.

[0007] On the basis of the above technical solution, preferably, the inorganic acid is a strong acid; the inorganic salt is a salt that can ionize hydrogen ions; the corrosion inhibitor is a nitrogen heterocyclic organic compound; and the scavenger is a hydroxyl radical scavenger.

[0008] On the basis of the above technical solution, preferably, the corrosion inhibitor is selected from one or more of 5-methyltetrazole, 5-aminotetrazole, benzotriazole, and imidazole compounds.

[0009] On the basis of the above technical solution, preferably, the scavenger is selected from one or more of fatty alcohol compounds, carboxylic acid compounds, aliphatic hydroxy acid compounds or ester compounds.

[0010] On the basis of the above technical scheme, preferably, the fatty alcohol compound is selected from one or more of glycerol, isopropanol, n-butanol or cyclohexanol; the carboxylic acid compound is selected from one or more of acetic acid, hexanoic acid, succinic acid, glutaric acid or phenylacetic acid; the aliphatic hydroxy acid compound is selected from one or more of the structural formula HO-CH2-[-CH2-] n -COOH compound; the ester compound is selected from the compound with the structural formula R-CH2-COO-CH2-R'; wherein n is any natural number.

[0011] On the basis of the above technical solution, preferably, the scavenger is selected from a mixture of fatty alcohol compounds and carboxylic acid compounds in any mass ratio, aliphatic hydroxy acid compounds or ester compounds.

[0012] On the basis of the above technical solution, preferably, the scavenger is selected from aliphatic hydroxy acid compounds and / or ester compounds.

[0013] On the basis of the above technical solution, preferably, the complexing agent is selected from one or more of hydroxyethylethylenediaminetriacetic acid, dimercaptosuccinic acid or ethylenediaminetetraacetic acid.

[0014] In a second aspect, the present invention provides a method for preparing the above copper etching solution composition, comprising the following steps:

[0015] S1. Prepare the raw materials according to the mass percentage;

[0016] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed and stirred, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0017] The copper etching solution composition and preparation method thereof provided by the present invention have the following beneficial effects compared with the prior art:

[0018] (1) The copper etching liquid composition provided by the present invention can significantly slow down the decomposition of hydrogen peroxide during the etching process, thereby maintaining excellent etching performance. Through precise control, the copper etching liquid composition of the present invention not only ensures the ideal etching cone angle and CD loss variation, but also avoids the generation of tail, ensuring that the substrate surface is clean and free of residue.

[0019] (2) The copper etching solution composition of the present invention can make the etching process more efficient and reliable, and prolong the effective service life of the solution, bringing significant advantages to the PCB / PWB production process.

[0020] (3) The copper etching liquid composition of the present invention ensures its etching performance by adding a hydroxyl radical scavenger and a complexing agent therein. On the one hand, the scavenger removes hydroxyl radicals to slow down the consumption of hydrogen peroxide, and on the other hand, the complexing agent complexes copper ions to reduce the content of copper ions in the liquid and slow down the catalytic effect on hydrogen peroxide. The synergistic effect of the two not only improves the overall performance of the etching liquid, but also ensures that no corrosion is caused to the glass substrate, maintains the integrity and safety of the substrate, and realizes the long-term stable operation of the etching process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a scanning electron microscope image of a substrate split after being processed in Example 1 of the present invention;

[0023] Figure 2 This is a scanning electron microscope image of a substrate split after being processed in Example 2 of the present invention;

[0024] Figure 3 This is a scanning electron microscope image of a substrate split after being processed in Example 3 of the present invention;

[0025] Figure 4 This is a scanning electron microscope image of a substrate split after being processed in Example 4 of the present invention;

[0026] Figure 5 This is a scanning electron microscope image of a substrate split after being processed in Example 5 of the present invention;

[0027] Figure 6 This is a scanning electron microscope image of a substrate split after being processed in Example 6 of the present invention;

[0028] Figure 7 This is a scanning electron microscope image of a substrate split after being processed in Comparative Example 1 of the present invention;

[0029] Figure 8 This is a scanning electron microscope image of a substrate split after being processed in Comparative Example 2 of the present invention;

[0030] Fig. 9 This is a scanning electron microscope image of a substrate split after being processed in Comparative Example 3 of the present invention;

[0031] Fig.10 This is a scanning electron microscope image of a substrate split after being processed in Comparative Example 4 of the present invention;

[0032] Figures 1 to 10 In the middle, the left picture is a scanning electron microscope image of the cross section of the lobe, and the right picture is a scanning electron microscope image of the inclined surface of the lobe;

[0033] Fig.11 This is a stability test chart of the copper etching solution composition prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0034] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Based on the phenomenon that as the etching process proceeds, the copper ion content in the solution increases, catalyzing the decomposition of hydrogen peroxide, thereby shortening the etching life of the solution, the inventors investigated the reason and found that the copper ion catalyzes the decomposition of hydrogen peroxide because the copper ion coordinates with hydrogen peroxide to form a copper-hydrogen peroxide complex as an intermediate. This complex can further undergo a redox reaction with the copper ion to generate copper oxide ions and hydroxyl radicals (·OH). The generated hydroxyl radicals then react with another hydrogen peroxide molecule to produce water and oxygen, and generate hydroxyl radicals again. This process is repeated continuously to form a self-sustaining free radical chain reaction.

[0036] In order to solve the above problems, the inventors proposed a method of adding a hydroxyl radical scavenger and a complexing agent into a copper etching solution.

[0037] In the technical solution of the present invention, the hydroxyl radical scavenger is used to remove the hydroxyl radicals generated in the process of copper ion catalyzing the decomposition of hydrogen peroxide. The principle is: a scavenger (such as fatty alcohols) extracts a hydrogen atom from the α-carbon of the alcohol to generate a carbon positive center radical (R·) with low reactivity, thereby shielding the effect of hydroxyl radicals in the system and blocking the free radical reaction chain, thereby slowing down the decomposition rate of hydrogen peroxide. At the same time, a complexing agent is added to adsorb and complex copper ions to form a stable complex, which can reduce the concentration of free copper ions in the solution on the one hand, and reduce the catalytic decomposition of hydrogen peroxide by copper ions on the other hand. The two components work together to effectively extend the service life of the etching solution, while maintaining the stability of the etching cone angle and the high-quality etching effect without residue and tail.

[0038] On the above basis, by controlling the amount of inorganic acid or inorganic salt, a suitable acidic environment is provided for the solution to assist hydrogen peroxide in oxidizing copper metal, while ensuring that the glass substrate is not damaged by excessive acidic substances.

[0039] The technical solution of the present invention is further described below in conjunction with specific examples. Unless otherwise specified, the sources of materials used in the examples are all commercially available conventional commodities.

[0040] Example 1

[0041] The copper etching liquid composition of this embodiment includes, by mass percentage, 10% hydrogen peroxide, 2% sulfuric acid (inorganic acid), 0.5% 5-methyltetrazole (corrosion inhibitor), 2% n-butanol (fatty alcohol scavenger), 3% hydroxyethylethylenediaminetriacetic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0042] S1. Prepare the raw materials according to the mass percentage;

[0043] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0044] Example 2

[0045] The copper etching liquid composition of this embodiment includes, by mass percentage, 15% hydrogen peroxide, 2% sulfuric acid (inorganic acid), 0.5% 5-methyltetrazole (corrosion inhibitor), 2% glutaric acid (carboxylic acid scavenger), 5% hydroxyethylethylenediaminetriacetic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0046] S1. Prepare the raw materials according to the mass percentage;

[0047] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0048] Example 3

[0049] The copper etching liquid composition of the present embodiment comprises, by mass percentage, 20% hydrogen peroxide, 1% sulfuric acid (inorganic acid) and 1% potassium hydrogen sulfate (inorganic salt), 0.5% benzotriazole (corrosion inhibitor), 1% cyclohexanol (fatty alcohol scavenger) and 1% acetic acid (carboxylic acid scavenger), 3% dimercaptosuccinic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0050] S1. Prepare the raw materials according to the mass percentage;

[0051] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0052] Example 4

[0053] The copper etching liquid composition of this embodiment includes, by mass percentage, 15% hydrogen peroxide, 1% sulfuric acid (inorganic acid) and 1% potassium hydrogen sulfate (inorganic salt), 0.5% benzotriazole (corrosion inhibitor), 1% 3-methyl-4-hydroxy-butyric acid (aliphatic hydroxy acid scavenger), 5% dimercaptosuccinic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0054] S1. Prepare the raw materials according to the mass percentage;

[0055] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0056] Example 5

[0057] The copper etching liquid composition of this embodiment includes, by mass percentage, 10% hydrogen peroxide, 2% potassium hydrogen sulfate (inorganic salt), 0.5% 5-aminotetrazole (corrosion inhibitor), 2% delta-valerolactone (ester scavenger), 3% hydroxyethylethylenediaminetriacetic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0058] S1. Prepare the raw materials according to the mass percentage;

[0059] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0060] Example 6

[0061] The copper etching liquid composition of this embodiment includes, by mass percentage, 20% hydrogen peroxide, 2% potassium hydrogen sulfate (inorganic salt), 0.5% 5-aminotetrazole (corrosion inhibitor), 2% ethyl butyrate (ester scavenger), 5% hydroxyethylethylenediaminetriacetic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0062] S1. Prepare the raw materials according to the mass percentage;

[0063] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0064] Example 7

[0065] The copper etching liquid composition of this embodiment includes, by mass percentage, 12% hydrogen peroxide, 2% sulfuric acid (inorganic acid), 0.5% 5-aminotetrazole (corrosion inhibitor), 1% glycerol (fatty alcohol scavenger) and 1% phenylacetic acid (carboxylic acid scavenger), 4% hydroxyethylethylenediaminetriacetic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0066] S1. Prepare the raw materials according to the mass percentage;

[0067] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0068] Example 8

[0069] The copper etching liquid composition of the present embodiment comprises, by mass percentage, 16% hydrogen peroxide, 1.5% sulfuric acid (inorganic acid), 0.5% 5-aminotetrazole (corrosion inhibitor) and 0.5% benzotriazole (corrosion inhibitor), a mixture of 1% 3-methyl-4-hydroxy-butyric acid (aliphatic hydroxy acid scavenger) and 1% delta-valerolactone (ester scavenger), 4% ethylenediaminetetraacetic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0070] S1. Prepare the raw materials according to the mass percentage;

[0071] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0072] Example 9

[0073] The copper etching liquid composition of this embodiment includes, by mass percentage, 14% hydrogen peroxide, 1% sulfuric acid (inorganic acid), 0.5% 2-methylimidazole (corrosion inhibitor), 2% isopropyl alcohol (aliphatic hydroxy acid scavenger), 4% dimercaptosuccinic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0074] S1. Prepare the raw materials according to the mass percentage;

[0075] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0076] Example 10

[0077] The copper etching liquid composition of this embodiment includes, by mass percentage, 18% hydrogen peroxide, 2% potassium hydrogen sulfate (inorganic salt), 0.5% 2-methylimidazole (corrosion inhibitor), 2% n-butanol (fatty alcohol scavenger), 5% ethylenediaminetetraacetic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0078] S1. Prepare the raw materials according to the mass percentage;

[0079] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0080] Embodiment 11

[0081] The copper etching liquid composition of this embodiment includes, by mass percentage, 13% hydrogen peroxide, 0.5% sulfuric acid (inorganic acid) and 1.5% potassium hydrogen sulfate (inorganic salt), 0.5% 5-aminotetrazole (corrosion inhibitor), 2% 3-n-butanol (fatty alcohol scavenger), 4% ethylenediaminetetraacetic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0082] S1. Prepare the raw materials according to the mass percentage;

[0083] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0084] Example 12

[0085] The copper etching liquid composition of this embodiment includes, by mass percentage, 8% hydrogen peroxide, 2% sulfuric acid (inorganic acid), 0.5% 5-methyltetrazole (corrosion inhibitor), 2% 3-methyl-4-hydroxy-butyric acid (aliphatic hydroxy acid scavenger), 5% dimercaptosuccinic acid (complexing agent), and the balance is deionized water. The copper etching liquid composition is prepared by the following steps:

[0086] S1. Prepare the raw materials according to the mass percentage;

[0087] S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed, stirred until completely dissolved, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

[0088] Comparative Example 1

[0089] The difference from Example 1 is that no scavenger is included, and the rest remains unchanged, and the preparation steps are the same as Example 1.

[0090] Comparative Example 2

[0091] The difference from Example 2 is that: no complexing agent is included, and an equal amount of δ-valerolactone (ester scavenger) is selected as the scavenger, and the rest remains unchanged, and the preparation steps are the same as Example 2.

[0092] Comparative Example 3

[0093] The difference from Example 3 is that no scavenger and complexing agent are included, and the rest remain unchanged, and the preparation steps are the same as Example 3.

[0094] Comparative Example 4

[0095] The difference from Example 4 is that it does not contain inorganic substances, and the rest remains unchanged, and the preparation steps are the same as Example 4.

[0096] Comparative Example 5

[0097] The raw materials remain the same as those in Example 5. The difference from Example 5 is that the preparation steps are as follows:

[0098] S1. Prepare the raw materials according to the mass percentage;

[0099] S2. Add hydrogen peroxide, inorganic substances, corrosion inhibitors, scavengers and complexing agents to deionized water in sequence, mix and stir until completely dissolved to obtain a copper etching solution composition.

[0100] (1) The above-mentioned embodiments 1 to 12 and comparative examples 1 to 5 were subjected to the following performance tests, and the test method was as follows: copper powder was added to the etching solution prepared in the above-mentioned embodiments and comparative examples to dissolve it. When the copper ions in the etching solution reached a concentration of 350ppm, 2000ppm, 4000ppm, 6000ppm, 8000ppm, 10000ppm, 11000ppm, 12000ppm, 13000ppm, etc., it was poured into an etching machine, and the copper substrate was sprayed at 32°C and 0.15Mpa for etching to obtain the etching time (EPD) of the substrate at this time. The judgment criterion is: when the difference between EPD and the initial EPD (350ppm) is greater than 5s, it means that the etching solution has reached its service life. The test results are shown in Table 1.

[0101] (2) In addition, taking the substrates obtained by processing in Examples 1 to 6 and Comparative Examples 1 to 4 as an example, the substrates after the experiment were split, and their cross sections and inclined surfaces were photographed with the help of a scanning electron microscope (SEM) to observe the etching cone angle, residue and tail. The test results are as follows: Figures 1 to 10 shown.

[0102] Table 1 Performance test results

[0103] Cone Angle / ° Etching performance Residue tail life Example 1 47-50 good none none 10000ppm Example 2 49-52 good none none 11000ppm Example 3 49-51 good none none 12000ppm Example 4 46-49 good none none 13000ppm Example 5 48-50 good none none 13000ppm Example 6 46-48 good none none 13000ppm Example 7 48-51 good none none 12000ppm Example 8 47-50 good none none 12500ppm Example 9 47-50 good none none 12000ppm Example 10 48-51 good none none 12500ppm Embodiment 11 47-50 good none none 12000ppm Example 12 46-49 good none none 11000ppm Comparative Example 1 57-59 Poor have have 6000ppm Comparative Example 2 60-64 Poor have have 6000ppm Comparative Example 3 59-62 Poor have have 4000ppm Comparative Example 4 / / / / / Comparative Example 5 55-58 Poor have have 7000ppm

[0104] Combining Table 1 and Figures 1 to 10 It can be seen that in Examples 1 to 12, due to the addition of scavengers and complexing agents, the decomposition of hydrogen peroxide is slowed down, the service life of the etching solution reaches 11000-13000ppm, and a stable and appropriate etching cone angle can be maintained, the substrate surface is clean and free of residue, and no tail appears, the etching performance is relatively stable, and we found that when esters are added or carboxylic acids and fatty alcohols are added at the same time, the etching life is relatively longer. This is because esters will hydrolyze into organic matter with hydroxyl and carboxyl groups in an acidic environment, which is equivalent to having two active substances that can remove hydroxyl radicals at the same time, which can further weaken the hydrolysis process of hydrogen peroxide.

[0105] By comparing Comparative Example 1 with Example 1, it can be seen that the lack of a scavenger causes the hydroxyl radicals generated by the decomposition of hydrogen peroxide to not be removed in a timely manner, and the free radical reaction chain continues to circulate, accelerating the decomposition of hydrogen peroxide, thereby shortening its service life, resulting in the appearance of some residues and tails.

[0106] By comparing Comparative Example 2 with Example 2, it can be seen that without the addition of a complexing agent, the copper ion concentration will become higher and higher, which greatly catalyzes the decomposition of hydrogen peroxide, shortens the life of the etching solution, and triggers other adverse reactions.

[0107] By comparing Comparative Example 3 with Example 3, it can be seen that due to the lack of both the scavenger and the complexing agent, the etching life is shorter. In this case, the decomposition rate of hydrogen peroxide is greatly increased, which not only leads to the rapid failure of the liquid, but also causes great waste of raw materials in industrial production and increases production costs.

[0108] By comparing Comparative Example 4 with Example 4, it can be seen that the inorganic acid / acidic inorganic salt can provide an acidic environment, which is helpful for hydrogen peroxide to etch metallic copper. In Comparative Example 4, due to the absence of acid, problems such as incomplete etching, unclear etching angle, and unclear film layer occurred. This shows that the inorganic acid / acidic inorganic salt is crucial to maintaining the effectiveness of the etching solution and the etching effect.

[0109] By comparing Comparative Example 5 with Example 5, the possible reasons for the performance degradation are analyzed as follows: (1) Since hydrogen peroxide is added earlier, it is exposed for a longer time during the subsequent addition of other components (such as inorganic acid, corrosion inhibitor, etc.), which increases its chance of contact with air and other reactive substances, resulting in accelerated decomposition of hydrogen peroxide. (2) The early addition of hydrogen peroxide causes the liquid to gradually lose its effectiveness during the preparation process, resulting in a decrease in the stability of the final prepared etching solution. This not only shortens the service life of the liquid, but may also affect its etching performance.

[0110] The inventors took the copper etching solution prepared in Example 1 as an example, took out 5000g, stirred it continuously at a constant speed in a water bath at 32°C, and used a temperature monitor to monitor the temperature change of the solution in real time to determine its stability. Fig.11 shown.

[0111] Depend on Fig.11 It can be seen that the copper etching solution prepared in this embodiment has a sudden boiling point after continuous stirring for about 108 hours, indicating that the solution has high stability, which also provides safety protection for the production process.

[0112] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A copper etching solution composition, characterized in that The raw materials include the following by mass percentage: 8-20% hydrogen peroxide, 0.5-2.5% inorganic matter, 0.05-2% corrosion inhibitor, 0.5-5% scavenger and 0.5-5% complexing agent, and the balance is deionized water; the inorganic matter is selected from inorganic acid and / or inorganic salt.

2. The copper etching solution composition according to claim 1, wherein The inorganic acid is a strong acid; the inorganic salt is a salt that can ionize hydrogen ions; the corrosion inhibitor is a nitrogen heterocyclic organic compound; and the scavenger is a hydroxyl radical scavenger.

3. The copper etching solution composition as claimed in claim 2, characterized in that The corrosion inhibitor is selected from one or more of 5-methyltetrazole, 5-aminotetrazole, benzotriazole and imidazole compounds.

4. The copper etching solution composition as claimed in claim 2, characterized in that The scavenger is selected from one or more of fatty alcohol compounds, carboxylic acid compounds, aliphatic hydroxy acid compounds or ester compounds.

5. The copper etching solution composition as claimed in claim 4, characterized in that The fatty alcohol compound is selected from one or more of glycerol, isopropanol, n-butanol or cyclohexanol; the carboxylic acid compound is selected from one or more of acetic acid, hexanoic acid, succinic acid, glutaric acid or phenylacetic acid; the aliphatic hydroxy acid compound is selected from one or more of the structural formula HO-CH2-[-CH2-] n -COOH compound; the ester compound is selected from the compound with a simplified structural formula of R-CH2-COO-CH2-R'; Wherein, n is any natural number.

6. The copper etching solution composition according to claim 5, wherein The scavenger is selected from a mixture of fatty alcohol compounds and carboxylic acid compounds in any mass ratio, aliphatic hydroxy acid compounds or ester compounds.

7. The copper etching solution composition according to claim 6, wherein The scavenger is selected from aliphatic hydroxy acid compounds and / or ester compounds.

8. The copper etching solution composition according to claim 1, wherein The complexing agent is selected from one or more of hydroxyethylethylenediaminetriacetic acid, dimercaptosuccinic acid or ethylenediaminetetraacetic acid.

9. A method for preparing the copper etching solution composition according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Prepare the raw materials according to the mass percentage; S2. Inorganic substances, corrosion inhibitors, scavengers and complexing agents are sequentially added into deionized water, mixed and stirred, and then hydrogen peroxide is added and stirred to obtain a copper etching solution composition.

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