Etching agent, preparation method and application thereof

Abstract

The present invention discloses an etchant, a preparation method and application thereof, and relates to the technical field of etching compositions. The etchant contains hydrogen peroxide, fluoride, etching inhibitor, chelating agent, etching stabilizer and angle improver, and can simultaneously etch copper and molybdenum-niobium metal layers through optimization of composition and ratio, simplifying etching steps and improving production efficiency; the etchant can also ensure the stability of the cone angle as the amount of metal copper ions increases.

Description

Technical Field

[0001] The present invention relates to the technical field of etching compositions, and in particular to an etching agent, a preparation method thereof and application thereof. Background Art

[0002] In order to reduce impedance and improve electrochemical performance, copper film is currently used instead of aluminum film. Metallic copper has been widely used because of its high conductivity and relatively low price. Although copper has good electrochemical properties, it will diffuse like other silicon nitride layers, so a buffer layer is generally added between the copper layer and the glass to increase the adhesion between the materials and prevent the diffusion of copper. The buffer layer is commonly used molybdenum niobium buffer layer.

[0003] The chemical properties of copper and molybdenum and niobium are somewhat different. If they are etched separately, it will result in a very cumbersome process, and the etchant for molybdenum and niobium is likely to react with copper, resulting in poor etching cone angle, copper over-etching, etc. For example, in the production line test, the etchant with hydrogen peroxide as the main oxidant has a significant increase in etching rate with the increase of copper ions, resulting in increased etching volume and angle.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The object of the present invention is to provide an etchant, a preparation method and application thereof, which can maintain both the etching rate and the stability of the cone angle under conditions of different copper ion concentrations when etching a copper layer and a molybdenum-niobium film layer.

[0006] The present invention is achieved in that:

[0007] In a first aspect, the present invention provides an etchant, which comprises, by mass percentage, 5.00wt%-30.00wt% of hydrogen peroxide, 0.01wt%-2.00wt% of fluoride, 0.10wt%-10.00wt% of etching inhibitor, 1.00wt%-4.00wt% of chelating agent, 1.00wt%-4.00wt% of etching stabilizer and 0.10wt%-2.00wt% of angle improver, and the balance is solvent;

[0008] The angle improver is selected from at least one of ammonium citrate, sodium citrate, triethyl citrate, potassium dihydrogen citrate, and diammonium hydrogen citrate.

[0009] By optimizing the composition and dosage of the etchant, introducing an angle improver, and adjusting the dosage of other components such as etching inhibitors, copper and molybdenum niobium can be etched at the same time, and as the metal copper ions increase, the stability of the cone angle can also be guaranteed.

[0010] In an optional embodiment, the present invention further comprises, by mass percentage, 0.10wt%-2.00wt% of an organic acid and 0.10wt%-2.00wt% of a pH adjuster; preferably, by mass percentage, 10.00wt%-25.00wt% of hydrogen peroxide, 0.05wt%-0.50wt% of a fluoride, 0.50wt%-1.50wt% of an organic acid, 0.10wt%-2.00wt% of an etching inhibitor, 1.00wt%-4.00wt% of a chelating agent, 1.00wt%-4.00wt% of an etching stabilizer, 0.10wt%-1.00wt% of a pH adjuster and 0.50wt%-0.90wt% of an angle improver, with the remainder being a solvent; preferably, the solvent is water.

[0011] By introducing organic acid and pH regulator, the pH value of the etchant is controlled within a more appropriate range to ensure that the reaction rate is controlled within an appropriate range to avoid over-fast or over-slow reactions. By optimizing the dosage of each component, the stability of the cone angle after etching is further improved.

[0012] In an alternative embodiment, the etching inhibitor is selected from at least one of 5-aminotetrazole, 5-methyltetrazole, methyltriazole, tolyltriazole and benzotriazole.

[0013] The use of the above etching inhibitors can further improve the stability of etching and avoid the cone angle increasing too quickly at high copper ion concentrations.

[0014] In an optional embodiment, the fluoride is selected from at least one of ammonium fluoride, sodium fluoride, ammonium bifluoride, sodium bifluoride, potassium fluoride and potassium bifluoride.

[0015] Fluorides mainly etch the molybdenum-niobium metal layer, and the etching rate can be guaranteed by the selection and dosage control of fluorides.

[0016] In an optional embodiment, the organic acid is selected from at least one of acetic acid, methanesulfonic acid, aminosulfonic acid and malonic acid. The addition of the organic acid can increase the reaction rate of copper with the molybdenum-niobium layer and reduce the molybdenum-niobium residue.

[0017] In an optional embodiment, the chelating agent is selected from at least one of aminoacetic acid, iminodiacetic acid, ethylenediaminetetraacetic acid, methanesulfonylacetic acid, tranexamic acid, nitrilotriacetic acid, sarcosine and glutamic acid.

[0018] During the etching process, the chelating agent chelates with the copper ions in the solution, thereby reducing the activity of the copper ions and slowing down the decomposition rate of hydrogen peroxide, thereby avoiding the phenomenon of exothermic explosion caused by the excessive decomposition of hydrogen peroxide during the reaction process.

[0019] In an alternative embodiment, the etching stabilizer is selected from at least one of ethylene glycol, triethylene glycol, propylene glycol, 1,3-butanediol and 1,4-butanediol.

[0020] The stability of the etching process is further improved by introducing an etching stabilizer, which is beneficial to further ensure the stability of the cone angle.

[0021] In an optional embodiment, the pH adjuster is selected from at least one of sodium sulfate, potassium sulfate, sodium bisulfate and potassium bisulfate.

[0022] The addition of the pH regulator optimizes the reaction rate of the copper / molybdenum-niobium film layer and prevents the reaction rate from being too fast or too slow.

[0023] In a second aspect, the present invention provides a method for preparing an etchant, which is prepared according to the composition of any one of the aforementioned embodiments. By optimizing the formula, the prepared etchant can simultaneously etch copper and molybdenum-niobium metal layers, and with the increase of metal copper ions, the stability of the cone angle can also be ensured;

[0024] Preferably, the preparation method comprises: mixing and filtering the raw materials according to a ratio.

[0025] In a third aspect, the present invention provides use of any one of the etchants in the aforementioned embodiments or the etchant prepared by the preparation method in the aforementioned embodiments in etching of copper-containing alloys;

[0026] Preferably, the copper-containing alloy is a copper-molybdenum-niobium alloy. The etchant provided by the present invention can etch copper and molybdenum-niobium metal layers simultaneously, and with the increase of metal copper ions, the stability of the cone angle can also be ensured.

[0027] The present invention has the following beneficial effects: the etchant provided by the present invention can simultaneously etch copper and molybdenum-niobium metal layers by optimizing the composition and ratio, thereby simplifying the etching steps and improving production efficiency; the etchant can also ensure the stability of the cone angle as the metal copper ions increase.

[0028] It should be added that if the cone angle increases with the increase of copper ions, the defective rate of the substrate in the production line will increase due to the excessively large cone angle under high copper ion concentration. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0030] Figure 1is a SEM cross-sectional view of the product after etching in Example 3 at Cu0ppm;

[0031] Figure 2 This is the SEM cross-sectional view of the product after etching in Example 3 at Cu2000ppm;

[0032] Figure 3 This is the SEM cross-sectional view of the product after etching in Example 3 at Cu4000ppm;

[0033] Figure 4 This is the SEM cross-sectional view of the product after etching in Example 3 at Cu6000ppm;

[0034] Figure 5 This is the SEM surface image of the product after etching in Example 3 under Cu0ppm. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0036] An embodiment of the present invention provides an etchant, which includes, by mass percentage, 5.00wt%-30.00wt% of hydrogen peroxide, 0.01wt%-2.00wt% of fluoride, 0.10wt%-10.00wt% of etching inhibitor, 1.00wt%-4.00wt% of chelating agent, 1.00wt%-4.00wt% of etching stabilizer and 0.10wt%-2.00wt% of angle improver, and the balance is solvent.

[0037] The inventors optimized the composition and dosage of the etchant, introduced an angle improver, and adjusted the dosage of other components such as etching inhibitors, so that copper and molybdenum niobium can be etched at the same time, and the stability of the cone angle can be ensured as the metal copper ions increase. Specifically, the angle improver is selected from at least one of ammonium citrate, sodium citrate, triethyl citrate, potassium dihydrogen citrate, and diammonium hydrogen citrate, and can be any one or more of the above.

[0038] In some embodiments, the composition comprises, by mass percentage, 5.00wt%-30.00wt% hydrogen peroxide, 0.01wt%-2.00wt% fluoride, 0.10wt%-2.00wt% organic acid, 0.10wt%-10.00wt% etching inhibitor, 1.00wt%-4.00wt% chelating agent, 1.00wt%-4.00wt% etching stabilizer, 0.10wt%-2.00wt% pH adjuster and 0.10wt%-2.00wt% angle improver, and the balance is solvent.

[0039] Specifically, the mass proportion of hydrogen peroxide can be 5.00wt%, 10.00wt%, 15.00wt%, 20.00wt%, 25.00wt%, 30.00wt%, etc.; the mass proportion of fluoride can be 0.01wt%, 0.05wt%, 0.10wt%, 0.50wt%, 1.00wt%, 1.50wt%, 2.00wt%, etc.; the mass proportion of organic acid can be 0.10wt%, 0.50wt%, 1.00wt%, 1.50wt%, 2.00wt%, etc.; the mass proportion of etching inhibitor can be 0.10wt%, 1.00wt%, 2.00wt%, 3.00wt%, 5. 00wt%, 8.00wt%, 10.00wt%, etc.; the mass proportion of the chelating agent can be 1.00wt%, 2.00wt%, 3.00wt%, 4.00wt%, etc.; the mass proportion of the etching stabilizer can be 1.00wt%, 2.00wt%, 3.00wt%, 4.00wt%, etc.; the mass proportion of the pH adjuster can be 0.10wt%, 0.50wt%, 1.00wt%, 1.50wt%, 2.00wt%, etc.; the mass proportion of the angle improver can be 0.10wt%, 0.50wt%, 0.70wt%, 0.90wt%, 1.00wt%, 1.50wt%, 2.00wt%, etc.

[0040] In a preferred embodiment, by mass percentage, the composition includes 10.00wt%-25.00wt% of hydrogen peroxide, 0.05wt%-0.50wt% of fluoride, 0.50wt%-1.50wt% of organic acid, 0.10wt%-2.00wt% of etching inhibitor, 1.00wt%-4.00wt% of chelating agent, 1.00wt%-4.00wt% of etching stabilizer, 0.10wt%-1.00wt% of pH regulator and 0.50wt%-0.90wt% of angle improver, and the balance is solvent, and the solvent is water (such as deionized water). By optimizing the dosage of each component, the stability of the cone angle after etching can be further improved.

[0041] Specifically, hydrogen peroxide is used as the main oxidant for copper, and its content is preferably 10.00-25.00wt%. When the amount of hydrogen peroxide falls within the above range, the copper and molybdenum niobium layers are etched at a more appropriate rate, and the pattern profile after etching is more excellent. If the above hydrogen peroxide content is lower than 5.00wt%, the copper metal layer can hardly be etched, and if it is higher than 30.00wt%, the total etching speed is too fast, difficult to control, and the cost is high.

[0042] Fluoride mainly etches the molybdenum-niobium metal layer. The fluoride content is 0.01-2.00wt%, preferably 0.05-0.50wt%. When the fluoride falls within this range, molybdenum-niobium can have a suitable etching speed, a better profile, and less residue. When the fluoride is lower than the lower limit of the above range, molybdenum-niobium is likely to have residues on the glass surface, resulting in defects; when the fluoride is higher than the upper limit of the above range, the fluoride ion content is too much, resulting in over-etching of copper, and the glass will also be etched by fluoride.

[0043] In some embodiments, the fluoride is selected from at least one of ammonium fluoride, sodium fluoride, ammonium bifluoride, sodium bifluoride, potassium fluoride and potassium bifluoride, and can be any one or more of the above.

[0044] The etching inhibitor is a cyclic amine compound, and the content of the etching inhibitor is 0.10wt%-10.00wt%, preferably 0.10wt%-2.00wt%. When the inhibitor content falls within the above range, a suitable copper etching speed can be formed, and the service life of the etchant can be effectively improved.

[0045] In some embodiments, the etching inhibitor is selected from at least one of 5-aminotetrazole, 5-methyltetrazole, methyltriazole, tolyltriazole and benzotriazole, and can be any one or more of the above. Preferably, the etching inhibitor is 5-methyltetrazole (5-methyltetrazole), and the use of 5-methyltetrazole can further improve the angle after etching and make the angle more stable.

[0046] During the etching process, the chelating agent chelates with the copper ions in the solution, thereby reducing the activity of the copper ions, reducing the decomposition rate of hydrogen peroxide, and avoiding the phenomenon of exothermic explosion caused by the excessive decomposition of hydrogen peroxide during the reaction process. The content of the chelating agent in the etchant is 1.00wt%-4.00wt%. When the chelating agent is less than 1.00wt%, the etchant cannot effectively chelate the metal ions as the copper ions increase, and the service life is low. When the chelating agent is higher than 4.00wt%, the excessive addition of the chelating agent will affect the etching rate and etching characteristics of the solution.

[0047] In some embodiments, the chelating agent is selected from at least one of aminoacetic acid, iminodiacetic acid, ethylenediaminetetraacetic acid, methylsulfonylacetic acid, tranexamic acid, nitrilotriacetic acid, sarcosine and glutamic acid, and can be any one or more of the above raw materials.

[0048] In some embodiments, the etching stabilizer can be selected from compounds with hydroxyl groups, such as ethylene glycol, triethylene glycol, propylene glycol, 1,3-butanediol and 1,4-butanediol, etc., and can be any one or more of the above raw materials. The etching stabilizer can improve the stability of the reaction process by reducing the decomposition rate of hydrogen peroxide. The content of the etching stabilizer is 1.00wt%-4.00wt%. When the content of the etching stabilizer is lower than 1.00wt%, the decomposition rate of hydrogen peroxide cannot be effectively reduced, and the reaction rate cannot be effectively controlled; when the content of the etching stabilizer is higher than 4.00wt%, the reaction rate is too slow, which will reduce production efficiency.

[0049] In some embodiments, the organic acid is selected from at least one of acetic acid, methanesulfonic acid, aminosulfonic acid and malonic acid, and may be any one or more of the above. The addition of organic acid can increase the reaction rate of copper with the molybdenum niobium layer and reduce the molybdenum niobium residue. The content of organic acid is 0.10wt%-2.00wt%, preferably 0.50wt%-1.50wt%. If the content of organic acid is lower than 0.10wt%, the reaction rate of copper with the molybdenum niobium layer is low, which will extend the total etching time; if the content of organic acid is higher than 2.00wt%, the reaction rate is faster and the reaction stability is poor.

[0050] In some embodiments, the pH adjuster is selected from at least one of sodium sulfate, potassium sulfate, sodium bisulfate and potassium bisulfate, and may be any one or more of the above. The content of the pH adjuster in the etchant is 0.10wt%-2.00wt%, preferably 0.10wt%-1.00wt%. When the dosage of the pH adjuster falls within the above range, the pH of the etchant composition can be adjusted to the most appropriate value, so that the reaction rate of the copper / molybdenum-niobium film layer reaches the best. When the pH adjuster is lower than 0.10wt%, the etchant cannot react effectively with the metal, or the reaction rate is too slow, and residual phenomenon occurs; when the pH adjuster is higher than 2.00wt%, excessive addition of the pH adjuster of the etchant will accelerate the etching speed of the solution, and too fast a reaction rate will result in excessive unilateral etching, which does not meet customer needs.

[0051] An embodiment of the present invention provides a method for preparing an etchant, which is prepared according to the composition of the above-mentioned etchant, that is, raw materials are weighed according to the content of each component and mixed evenly.

[0052] In some embodiments, the preparation method includes: mixing hydrogen peroxide, fluoride, organic acid, etching inhibitor, chelating agent, etching stabilizer, pH adjuster, angle improver and water according to a ratio, and obtaining the etchant through circulating filtration.

[0053] It should be noted that the etchant prepared by the present invention is suitable for etching copper-containing alloys, particularly copper-molybdenum-niobium alloys, and can etch copper and molybdenum-niobium metal layers, simplifying the etching steps and improving production efficiency; the etchant can also ensure the stability of the cone angle as the metal copper ions increase.

[0054] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0055] Example 1

[0056] The present embodiment provides an etchant, which includes, by mass percentage, 25.00 wt% of hydrogen peroxide, 0.50 wt% of ammonium bifluoride (fluoride), 1.00 wt% of acetic acid (organic acid), 0.20 wt% of 5-methyltetrazole (etching inhibitor), 1.00 wt% of iminodiacetic acid (chelating agent), 2.00 wt% of ethylene glycol (etching stabilizer), 0.50 wt% of sodium sulfate (pH adjuster) and 1.00 wt% of sodium citrate (angle improver A), and the balance is deionized water.

[0057] The present embodiment also provides a method for preparing an etching agent, comprising: weighing raw materials according to the formula composition provided in the present embodiment, controlling the total mass to be 10 kg, and mixing the components uniformly and filtering.

[0058] The compositions of the etchants prepared in Examples 1-12 and Comparative Examples 1-4 are shown in Table 1. The total mass of Examples 1-12 and Comparative Examples 1-4 is controlled to be 10 kg, the etching inhibitors provide two types of cyclic amine compounds A and cyclic amine compounds B, the angle improvers provide two types of angle improvers A and angle improvers B, and the types and proportions of the raw materials used in different Examples and Comparative Examples are shown in Table 1. Among them, the cyclic amine compound A represents 5-aminotetrazole, the cyclic amine compound B represents 5-methyltetrazole, the angle improver A represents sodium citrate, and the angle improver B represents potassium dihydrogen citrate.

[0059] Table 1 Composition of the etchants provided in the examples and comparative examples (%)

[0060]

[0061]

[0062] Test Example 1

[0063] 10kg of the etchant mixture of Examples 1-12 and Comparative Examples 1-4 were poured into a mini etching device, respectively, and the etching was performed after the temperature reached 30±0.1°C. The total etching time (EPD) was 1.5 times the sum of the copper etching time and the molybdenum-niobium alloy etching time under the condition of Cu ion concentration of 0ppm. After the etching was completed, it was rinsed with deionized water within 2 seconds, and the surface moisture was blown dry to obtain a test sample of Cu 0ppm. 20g of copper powder was added to the 10kg etchant mixture, stirred for 30 minutes, and poured into the mini etcher after the copper powder was completely dissolved, and the test sample of Cu 2000ppm was started. 40g of copper powder was added to the 10kg etchant mixture, stirred for 30 minutes, and poured into the mini etcher after the copper powder was completely dissolved, and the test sample of Cu 4000ppm was started. 60g of copper powder was added to the 10kg etchant mixture, stirred for 30 minutes, and poured into the mini etcher after the copper powder was completely dissolved, and the test sample of Cu 6000ppm was started. After completion, a scanning electron microscope (SEM) was used to evaluate the performance parameters after etching. The results are shown in Table 2 below.

[0064] Table 2 Etching effect test results of embodiments and comparative examples

[0065]

[0066] As shown in Table 2, compared with Example 2, Example 1 has a larger amount of angle improver A added. Although the angle change is very low, it does not meet the usual manufacturer's requirement of an etching angle of 38°-55°. Example 3 has an angle increase of 8.7° from 44.9° to 53.6° from Cu 0ppm-Cu 6000ppm, which is a certain improvement compared with the comparative example, but the effect is not obvious due to the low addition of angle improver A. The etching inhibitor of Experimental Example 4 is cyclic amine compound A, the etching inhibitor of Experimental Example 5 is cyclic amine compound A and cyclic amine compound B, and the etching inhibitor of Experimental Example 6 is cyclic amine compound B. By comparing Experimental Examples 4-6, it can be found that under the combined action of cyclic amine compound B and angle improver, from Cu 0ppm-Cu 6000ppm, the angle increase is small. The angle of Experimental Example 6 increases from 45.9° to 47.0°, which only increases by 1.1°, achieving a very good angle improvement effect. Experimental Examples 7-12 adjusted the contents of hydrogen peroxide, fluoride, organic acid, chelating agent, pH regulator, and etching stabilizer, respectively. Compared with the comparative example, the angle was significantly improved. From Cu 0ppm to Cu 6000ppm, the angle increase was less than 6°, and the maximum angle of Cu 6000ppm was less than 55°, which met the angle requirements of most manufacturers.

[0067] The etchant compositions of Comparative Examples 1-4 do not contain an angle improver. Comparative Examples 1 and 2 use cyclic amine compound A as an etching inhibitor. When the etchant composition is from Cu 0ppm to 6000ppm, the angle increases by about 12°. During production line testing, the angle increases too much and causes defects. Comparative Examples 3 and 4 use cyclic amine compound B as an etching inhibitor, but still fail to meet the manufacturer's requirement of an etching angle of 38° to 55°.

[0068] It can be seen from the experimental examples that when the cyclic amine compound B is used in combination with the angle improver, the angle increase of the etchant composition is significantly reduced from Cu 0ppm-6000ppm, meeting the manufacturer's requirements for the etching angle, and can continue to be used under high copper ion concentrations, thereby increasing the life of the etchant and saving costs.

[0069] Figure 1-Figure 5 These are the SEM images of etching under different copper concentrations:

[0070] Figure 1 is the SEM cross-sectional view of Example 3 at Cu0ppm, from Figure 1 It can be seen that after the etching agent composition of this embodiment etches the metal copper / molybdenum-niobium alloy, the cone angle is 40-50° and is straight without bending, and the etching effect is very good.

[0071] Figure 2 is the SEM cross-sectional view of Example 3 at Cu2000ppm, from Figure 2 It can be seen that after the etching agent composition of this embodiment etches the metal copper / molybdenum-niobium alloy, the cone angle is 40-50° and is straight without bending, and the etching effect is very good.

[0072] Figure 3 is the SEM cross-sectional view of Example 3 at Cu4000ppm, from Figure 3 It can be seen that after the etching agent composition of this embodiment etches the metal copper / molybdenum-niobium alloy, the cone angle is 40-50° and is straight without bending, and the etching effect is very good.

[0073] Figure 4 is the SEM cross-sectional view of Example 3 at Cu6000ppm, from Figure 4 It can be seen that after the etching agent composition of this embodiment etches the metal copper / molybdenum-niobium alloy, the cone angle is 40-50° and is straight without bending, and the etching effect is very good.

[0074] Figure 5 is the SEM surface image of Example 3 at Cu0ppm, from Figure 5 It can be seen that the etching agent composition of this embodiment has a very good removal effect on the metal copper / molybdenum-niobium alloy, and no residue occurs.

[0075] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An etching agent, characterized in that: The composition comprises, by mass percentage, 10.00wt%-25.00wt% of hydrogen peroxide, 0.05wt%-0.50wt% of fluoride, 0.50wt%-2.00wt% of organic acid, 0.10wt%-2.00wt% of etching inhibitor, 1.00wt%-4.00wt% of chelating agent, 1.00wt%-4.00wt% of etching stabilizer, 0.10wt%-1.00wt% of pH adjuster and 0.50wt%-0.90wt% of angle improver, and the balance is solvent; Wherein, the angle improving agent is selected from at least one of sodium citrate and potassium dihydrogen citrate; The etching inhibitor is 5-methyltetrazolyl.

2. The etching agent according to claim 1, characterized in that The solvent is water.

3. The etching agent according to claim 1, characterized in that The fluoride is selected from at least one of ammonium fluoride, sodium fluoride, ammonium bifluoride, sodium bifluoride, potassium fluoride and potassium bifluoride.

4. The etching agent according to claim 1, characterized in that The organic acid is selected from at least one of acetic acid, methanesulfonic acid, aminosulfonic acid and malonic acid.

5. The etching agent according to claim 1, characterized in that The chelating agent is selected from at least one of iminodiacetic acid, ethylenediaminetetraacetic acid, methylsulfonylacetic acid, tranexamic acid, nitrilotriacetic acid, sarcosine and glutamic acid.

6. The etching agent according to claim 1, characterized in that The etching stabilizer is selected from at least one of ethylene glycol, triethylene glycol, propylene glycol, 1,3-butanediol and 1,4-butanediol.

7. The etching agent according to claim 1, characterized in that The pH regulator is selected from at least one of sodium sulfate, potassium sulfate, sodium bisulfate and potassium bisulfate.

8. A method for preparing an etching agent, characterized in that: The etchant is prepared according to the composition of any one of claims 1 to 7.

9. The preparation method according to claim 8, comprising: Mix and filter the raw materials according to the ratio.

10. Use of the etchant according to any one of claims 1 to 7 or the etchant prepared by the preparation method according to any one of claims 8 to 9 in etching of copper-containing alloys.

11. The use according to claim 10, characterized in that: The copper-containing alloy is a copper-molybdenum-niobium alloy.

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