CN116219439A

CN116219439A - Etchant, preparation method and application thereof

Info

Publication number: CN116219439A
Application number: CN202310084556.2A
Authority: CN
Inventors: 张伟明; 聂航; 章学春; 沈楠; 李玉兴
Original assignee: Shanghai Shengjian Microelectronics Co ltd
Current assignee: Shanghai Shengjian Microelectronics Co ltd
Priority date: 2023-01-31
Filing date: 2023-01-31
Publication date: 2023-06-06

Abstract

The 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 optimizing the composition and the proportion, so that the etching step is simplified, and the production efficiency is improved; the etchant can also ensure the stability of the cone angle along with the increase of metal copper ions.

Description

Etchant, preparation method and application thereof

Technical Field

The invention relates to the technical field of etching compositions, in particular to an etchant, a preparation method and application thereof.

Background

In order to reduce the impedance and improve the electrochemical performance, a copper film layer is currently selected to replace an aluminum film layer. Copper metal has been widely used because of its high conductivity and relatively low cost. Copper has good electrochemical performance, but can diffuse like other silicon nitride layers, so a buffer layer is generally added between the copper layer and glass, not only can the adhesiveness between materials be increased, but also the diffusion of copper can be prevented. The buffer layer is more commonly a molybdenum niobium buffer layer.

Copper and molybdenum niobium have certain difference in chemical properties, and if the copper and molybdenum niobium are etched separately, complicated procedures are caused, and the etchant of molybdenum niobium is likely to react with copper, so that phenomena of poor etching taper angle, over etching of copper and the like occur. For example, in the production line test, the etching rate is significantly increased with the increase of copper ions, which causes problems such as an increase in etching amount and an increase in angle.

In view of this, the present invention has been made.

Disclosure of Invention

The invention aims to provide an etchant, a preparation method and application thereof, and the etchant can maintain the etching rate and the cone angle stability under the condition of copper ions with different concentrations when etching a copper layer and a molybdenum-niobium film layer.

The invention is realized in the following way:

in a first aspect, the present invention provides an etchant comprising, by mass, 5.00wt% to 30.00wt% hydrogen peroxide, 0.01wt% to 2.00wt% fluoride, 0.10wt% to 10.00wt% etching inhibitor, 1.00wt% to 4.00wt% chelating agent, 1.00wt% to 4.00wt% etching stabilizer, and 0.10wt% to 2.00wt% angle improver, the balance being solvent;

the angle improver is at least one selected from ammonium citrate, sodium citrate, triethyl citrate, potassium dihydrogen citrate and diammonium hydrogen citrate.

By optimizing the composition and the dosage of the etchant, the copper and the molybdenum niobium can be etched simultaneously by introducing the angle improver and adjusting the dosage of other components such as the etching inhibitor, and the stability of the cone angle can be ensured along with the increase of metal copper ions.

In an alternative embodiment, the organic acid is 0.10wt% to 2.00wt% and the pH regulator is 0.10wt% to 2.00wt% in terms of mass percent; preferably, the composition comprises, by mass, 10.00wt% to 25.00wt% of hydrogen peroxide, 0.05wt% to 0.50wt% of fluoride, 0.50wt% to 1.50wt% of an organic acid, 0.10wt% to 2.00wt% of an etching inhibitor, 1.00wt% to 4.00wt% of a chelating agent, 1.00wt% to 4.00wt% of an etching stabilizer, 0.10wt% to 1.00wt% of a pH regulator and 0.50wt% to 0.90wt% of an angle improver, with the balance being a solvent; preferably, the solvent is water.

By introducing the organic acid and the pH regulator, the pH value of the etchant is controlled in a proper range, so that the reaction rate is controlled in a proper range, and the excessively fast and slow reaction is avoided. The stability of the taper angle after etching is further improved by optimizing the amount of each component.

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

The etching inhibitors can further improve the stability of etching, and avoid the increase of cone angle at high copper ion concentration.

In an alternative embodiment, the fluoride is selected from at least one of ammonium fluoride, sodium fluoride, ammonium bifluoride, sodium bifluoride, potassium fluoride, and potassium bifluoride.

The fluoride is mainly used for etching the molybdenum-niobium metal layer, and the etching rate can be ensured through the selection and the dosage control of the fluoride.

In an alternative embodiment, the organic acid is selected from at least one of acetic acid, methanesulfonic acid, sulfamic acid, and malonic acid. The addition of the organic acid can improve the reaction speed of the copper and the molybdenum-niobium layer and reduce the molybdenum-niobium residue.

In an alternative embodiment, the chelating agent is selected from at least one of glycine diacetic acid, iminodiacetic acid, ethylenediamine tetraacetic acid, methylsulfonyl acetic acid, tranexamic acid, nitrilotriacetic acid, sarcosine, and glutamic acid.

The chelating agent performs chelation with copper ions in the solution in the etching process, so that the activity of the copper ions is reduced, the decomposition speed of hydrogen peroxide is reduced, and the phenomenon of exothermic explosion caused by too fast decomposition of the hydrogen peroxide in the reaction process is avoided.

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

The stability of the etching process is further improved by introducing the etching stabilizer, which is beneficial to further ensuring the stability of the taper angle.

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

The addition of the pH regulator can optimize the reaction speed of the copper/molybdenum niobium film layer and prevent the reaction speed from being too fast or too slow.

In a second aspect, the present invention provides a method for preparing an etchant, according to any one of the foregoing embodiments, by optimizing a formulation, the prepared etchant can simultaneously etch a copper layer and a molybdenum-niobium metal layer, and as the metal copper ions increase, the stability of a taper angle can be ensured;

preferably, the preparation method comprises the following steps: mixing the raw materials according to the proportion, and filtering.

In a third aspect, the present invention provides the use of an etchant according to any one of the preceding embodiments or an etchant prepared by a method of preparation according to the preceding embodiments in etching copper-containing alloys;

preferably, the copper-containing alloy is a copper-molybdenum-niobium alloy. The etchant provided by the invention can simultaneously etch the copper and the molybdenum-niobium metal layers, and can ensure the cone angle stability along with the increase of metal copper ions.

The invention has the following beneficial effects: the etchant provided by the invention can simultaneously etch the copper and molybdenum-niobium metal layers through optimizing the composition and the proportion, so that the etching steps are simplified, and the production efficiency is improved; the etchant can also ensure the stability of the cone angle along with the increase of metal copper ions.

It should be added that if the taper angle increases with increasing copper ions, the substrate in the production line may have an increased yield due to an excessively large taper angle at a high copper ion concentration.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is an SEM cross-sectional view of the etched product of example 3 at 0ppm Cu;

FIG. 2 is an SEM cross-sectional view of the etched product of example 3 at Cu2000 ppm;

FIG. 3 is an SEM cross-sectional view of the etched product of example 3 at 4000ppm Cu;

FIG. 4 is an SEM cross-sectional view of the etched product of example 3 at Cu6000 ppm;

FIG. 5 is an SEM surface view of the etched product of example 3 at 0ppm Cu.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

The embodiment of the invention provides an etchant, which comprises 5.00-30.00 wt% of hydrogen peroxide, 0.01-2.00wt% of fluoride, 0.10-10.00 wt% of etching inhibitor, 1.00-4.00 wt% of chelating agent, 1.00-4.00 wt% of etching stabilizer, 0.10-2.00 wt% of angle improver and the balance of solvent according to mass percent.

The inventor can etch copper and molybdenum niobium simultaneously by optimizing the composition and the dosage of the etchant, introducing the angle improver and adjusting the dosage of other components such as the etching inhibitor, and can ensure the stability of the cone angle along with the increase of metal copper ions. Specifically, the angle improver is at least one selected from ammonium citrate, sodium citrate, triethyl citrate, potassium dihydrogen citrate and diammonium hydrogen citrate, and can be any one or more of the above.

In some embodiments, the composition comprises, by mass, 5.00wt% to 30.00wt% hydrogen peroxide, 0.01wt% to 2.00wt% fluoride, 0.10wt% to 2.00wt% organic acid, 0.10wt% to 10.00wt% etching inhibitor, 1.00wt% to 4.00wt% chelating agent, 1.00wt% to 4.00wt% etching stabilizer, 0.10wt% to 2.00wt% pH regulator, and 0.10wt% to 2.00wt% angle improver, with the balance being solvent.

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

In a preferred embodiment, the composition comprises, by mass, 10.00wt% to 25.00wt% hydrogen peroxide, 0.05wt% to 0.50wt% fluoride, 0.50wt% to 1.50wt% organic acid, 0.10wt% to 2.00wt% etching inhibitor, 1.00wt% to 4.00wt% chelating agent, 1.00wt% to 4.00wt% etching stabilizer, 0.10wt% to 1.00wt% pH regulator and 0.50wt% to 0.90wt% angle improver, with the balance being solvent, water (e.g., deionized water). The stability of the taper angle after etching is further improved by optimizing the amount of each component.

Specifically, hydrogen peroxide is preferably contained in an amount of 10.00 to 25.00wt% as a main oxidizing agent for copper, and when the amount of hydrogen peroxide falls within the above range, the copper and molybdenum niobium layers are etched at a more suitable rate, and the pattern profile after etching is more excellent. If the above hydrogen peroxide content is less than 5.00wt%, the copper metal layer is not substantially etched, whereas if it is more than 30.00wt%, the total etching rate is too fast, difficult to control, and the cost is high.

The fluoride mainly etches the molybdenum-niobium metal layer, the content of the fluoride is 0.01-2.00wt%, preferably 0.05-0.50wt%, when the fluoride falls in the range, the molybdenum-niobium can have proper etching speed, has better outline and less residue, and when the fluoride falls below the lower limit of the range, the molybdenum-niobium is easy to have residue on the surface of glass, so that the defect is caused; when the fluoride is higher than the upper limit of the above range, the fluorine ion content is too large, which results in excessive etching of copper and etching of glass by the fluoride.

In some embodiments, the fluoride is at least one selected from the group consisting of ammonium fluoride, sodium fluoride, ammonium bifluoride, sodium bifluoride, potassium fluoride and potassium bifluoride, and may be any one or more of the above.

The etching inhibitor is cyclic amine compound, and the content of the etching inhibitor is 0.10wt% to 10.00wt%, preferably 0.10wt% to 2.00wt%. When the inhibitor amount falls within the above range, a proper copper etching rate can be formed and the service life of the etchant can be effectively improved.

In some embodiments, the etching inhibitor is selected from at least one of 5-aminotetrazole, 5-methyltetrazole, methyltriazole, tolyltriazole, and benzotriazole, which may 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, so that the angle is more stable.

The chelating agent performs chelation with copper ions in the solution in the etching process, so that the activity of the copper ions is reduced, the decomposition speed of hydrogen peroxide is reduced, and the phenomenon of exothermic explosion caused by too fast decomposition of the hydrogen peroxide in the reaction process is avoided. The chelating agent content in the etchant is 1.00wt% to 4.00wt%. When the chelating agent is less than 1.00wt%, the etchant increases with copper ions, metal ions cannot be effectively chelated, the lifetime is low, and when the chelating agent is more than 4.00wt%, the excessive addition of the chelating agent affects the etching rate and etching characteristics of the chemical solution.

In some embodiments, the chelating agent is at least one selected from the group consisting of glycine diacetic acid, iminodiacetic acid, ethylenediamine tetraacetic acid, methylsulfonyl acetic acid, tranexamic acid, nitrilotriacetic acid, sarcosine, and glutamic acid, and may be any one or more of the above raw materials.

In some embodiments, the etching stabilizer may be a compound with hydroxyl, such as ethylene glycol, triethylene glycol, propylene glycol, 1,3 butanediol, 1,4 butanediol, etc., and may be any one or more of the above materials. The etching stabilizer can improve the stability of the reaction process by reducing the decomposition speed of hydrogen peroxide. The content of the etching stabilizer is 1.00-4.00 wt%, when the content of the etching stabilizer is lower than 1.00wt%, the decomposition rate of hydrogen peroxide can not be effectively reduced, and the reaction rate can not be effectively controlled; when the content of the etching stabilizer is more than 4.00wt%, the reaction rate is too slow, which may lower the production efficiency.

In some embodiments, the organic acid is at least one selected from acetic acid, methanesulfonic acid, sulfamic acid, and malonic acid, and may be any one or more of the above. The addition of the organic acid can improve the reaction speed of the copper and the molybdenum-niobium layer and reduce the molybdenum-niobium residue. The content of the organic acid is 0.10wt% to 2.00wt%, preferably 0.50wt% to 1.50wt%. If the organic acid content is lower than 0.10wt%, the reaction speed of the copper and the molybdenum-niobium layer is lower, and the total etching time can be prolonged; if the organic acid content is higher than 2.00wt%, the reaction rate is faster and the reaction stability is poor.

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 pH regulator content in the etchant is 0.10wt% to 2.00wt%, preferably 0.10wt% to 1.00wt%, and when the pH regulator dosage falls within the above range, the pH of the etchant composition can be adjusted to the most suitable value so that the reaction rate of the copper/molybdenum niobium film layer is optimized. When the pH adjustor is less than 0.10wt%, the etchant does not react with the metal effectively or the reaction speed is too slow, and a residual phenomenon occurs; when the pH regulator is higher than 2.00wt%, excessive addition of the pH regulator of the etchant accelerates the etching speed of the liquid medicine, and the reaction speed is too high, so that the single-side etching amount is too large, and the requirement of customers is not met.

The embodiment of the invention provides a preparation method of an etchant, which is prepared according to the composition of the etchant, namely, raw materials are weighed according to the content of each component, and the raw materials are uniformly mixed.

In some embodiments, the method of making comprises: hydrogen peroxide, fluoride, organic acid, etching inhibitor, chelating agent, etching stabilizer, pH regulator, angle improver and water are mixed in proportion, and the etchant is obtained through cyclic filtration.

The etchant prepared by the method is suitable for etching copper-containing alloy, particularly copper-molybdenum-niobium alloy, can etch copper and molybdenum-niobium metal layers, simplifies etching steps and improves production efficiency; the etchant can also ensure the stability of the cone angle along with the increase of metal copper ions.

The features and capabilities of the present invention are described in further detail below in connection with the examples.

Example 1

The present example provides an etchant comprising, by mass, 25.00% hydrogen peroxide, 0.50% ammonium bifluoride, 1.00% acetic acid (organic acid), 0.20% 5-methyltetrazole (etching inhibitor), 1.00% iminodiacetic acid (chelating agent), 2.00% ethylene glycol (etching stabilizer), 0.50% sodium sulfate (pH regulator) and 1.00% sodium citrate (angle improver a), the balance being deionized water.

The embodiment also provides a preparation method of the etchant, which comprises the following steps: the raw materials are weighed according to the formula composition provided in the embodiment, the total mass is controlled to be 10kg, and the components are uniformly mixed and filtered.

The etchant compositions prepared in examples 1 to 12 and comparative examples 1 to 4 are shown in Table 1, and the total mass of examples 1 to 12 and comparative examples 1 to 4 is controlled to 10kg, the etching inhibitor provides both of the cyclic amine compound A and the cyclic amine compound B, the angle improver provides both of the angle improver A and the angle improver B, and the kinds and proportions of the raw materials used in the different examples and comparative examples are shown in Table 1. Wherein 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.

Table 1 composition of etchant (%)

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Test example 1

10kg of the etchant mixtures of examples 1 to 12 and comparative examples 1 to 4 were respectively poured into a mini etching apparatus, and after the temperature reached 30.+ -. 0.1 ℃ and etching was performed, total etching time (EPD): the total etching time of the molybdenum-niobium alloy is 1.5 times that of the copper under the condition of the Cu ion concentration of 0 ppm. After etching, washing with deionized water within 2 seconds, drying the surface moisture to obtain a Cu0ppm test sample, adding 20g of copper powder into 10kg of etchant mixture, stirring for 30 minutes, pouring the copper powder into a Mi-you-etching machine after the copper powder is completely dissolved, starting to test the Cu2000ppm test sample, adding 40g of copper powder into 10kg of etchant mixture, stirring for 30 minutes, pouring the copper powder into the Mi-you-etching machine after the copper powder is completely dissolved, starting to test the Cu4000ppm test sample, adding 60g of copper powder into 10kg of etchant mixture, stirring for 30 minutes, pouring the copper powder into the Mi-you-etching machine after the copper powder is completely dissolved, and starting to test the Cu6000ppm test sample. After completion, the post-etch performance parameters were evaluated using a Scanning Electron Microscope (SEM), and the results are shown in table 2 below.

Table 2 results of etching effect test of examples and comparative examples

As is clear from Table 2, example 1 was more added than example 2, and the angle improver A was not satisfactory to the typical manufacturer's requirements for an etching angle of 38 DEG to 55 DEG, although the angle change was very low. Example 3 increased from Cu0ppm to Cu6000ppm, increasing the angle from 44.9 to 53.6, increasing by 8.7, with some improvement over the comparative example, but the effect was not apparent due to too low addition of angle improver A. The etching inhibitors of experimental example 4 were cyclic amine compound a, experimental example 5 were cyclic amine compound a and cyclic amine compound B, and experimental example 6 was cyclic amine compound B, and it was found that the angle of experimental example 6 was increased from 45.9 ° to 47.0 ° by the combination of the cyclic amine compound B with the angle improver from Cu0ppm to Cu6000ppm, and only 1.1 °, thereby achieving a very good angle improving effect. Experimental examples 7-12 respectively adjust the contents of hydrogen peroxide, fluoride, organic acid, chelating agent, pH regulator and etching stabilizer, and compared with comparative examples, the angles are also obviously improved, the angle increment is smaller than 6 degrees from Cu0ppm to Cu6000ppm, the maximum angles of Cu6000ppm are smaller than 55 degrees, and the angle requirements of most manufacturers are met.

The etchant compositions of comparative examples 1 to 4 each did not contain an angle improver, and the use of the cyclic amine compound a as an etching inhibitor in comparative examples 1 and 2 resulted in an increase in the angle of about 12 ° from Cu0ppm to 6000ppm, and in the case of the line test, the increase in the angle was too high, which resulted in defects. Comparative example 3 and comparative example 4 still did not meet the manufacturer's etching angle of 38 ° -55 ° using the cyclic amine compound B as an etching inhibitor.

From experimental examples, it can be known that when the cyclic amine compound B is combined with the angle improver, the angle increase of the etchant composition is obviously reduced from Cu0ppm to 6000ppm, thereby meeting the requirements of manufacturers on etching angles, and the etchant can be continuously used under the condition of high copper ion concentration, thereby prolonging the service life of the etchant and saving the cost.

Fig. 1-5 are SEM images of etching at different copper concentrations, respectively:

FIG. 1 is a SEM sectional view of the present example 3 at Cu0ppm, and as can be seen from FIG. 1, this example etchesPost-etch of metallic copper/molybdenum niobium alloys by etchant compositions _， The taper angle is 40-50 degrees, the etching effect is very good, and the etching effect is straight and not bent.

Fig. 2 is a SEM cross-sectional view of the present example 3 at Cu2000ppm, and as can be seen from fig. 2, the etchant composition of this example has a very good etching effect after etching of the metallic copper/molybdenum niobium alloy, with a taper angle of 40-50 ° and straightness without bending.

Fig. 3 is a SEM cross-sectional view of the present example 3 at 4000ppm Cu, and it can be seen from fig. 3 that the etchant composition of the present example has excellent etching effect after etching of the metallic copper/molybdenum niobium alloy with a taper angle of 40-50 ° and straightness without bending.

Fig. 4 is a SEM cross-sectional view of the present example 3 at Cu6000ppm, and as can be seen from fig. 4, the etchant composition of the present example has a very good etching effect after etching the metallic copper/molybdenum niobium alloy, with a taper angle of 40-50 ° and straightness without bending.

Fig. 5 is a SEM surface view of the present example 3 at 0ppm Cu, and it can be seen from fig. 5 that the etchant composition of this example has a very good effect of removing the metallic copper/molybdenum niobium alloy, and no residue occurs.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An etchant characterized by comprising 5.00wt% to 30.00wt% of hydrogen peroxide, 0.01wt% to 2.00wt% of fluoride, 0.10wt% to 10.00wt% of etching inhibitor, 1.00wt% to 4.00wt% of chelating agent, 1.00wt% to 4.00wt% of etching stabilizer and 0.10wt% to 2.00wt% of angle improver, and the balance being solvent;

wherein the angle improver is at least one selected from ammonium citrate, sodium citrate, triethyl citrate, potassium dihydrogen citrate and diammonium hydrogen citrate.

2. The etchant according to claim 1, further comprising, in mass%, 0.10wt% to 2.00wt% of an organic acid and 0.10wt% to 2.00wt% of a pH adjuster;

preferably, the composition comprises, by mass, 10.00wt% to 25.00wt% of hydrogen peroxide, 0.05wt% to 0.50wt% of fluoride, 0.50wt% to 1.50wt% of an organic acid, 0.10wt% to 2.00wt% of an etching inhibitor, 1.00wt% to 4.00wt% of a chelating agent, 1.00wt% to 4.00wt% of an etching stabilizer, 0.10wt% to 1.00wt% of a pH regulator and 0.50wt% to 0.90wt% of an angle improver, with the balance being a solvent;

preferably, the solvent is water.

3. The etchant according to claim 1 or 2, wherein the etching inhibitor is selected from at least one of 5-aminotetrazole, 5-methyltetrazole, methyltriazole, tolyltriazole, and benzotriazole.

4. The etchant according to claim 1 or 2, wherein the fluoride is at least one selected from the group consisting of ammonium fluoride, sodium fluoride, ammonium bifluoride, sodium bifluoride, potassium fluoride and potassium bifluoride.

5. The etchant of claim 2, wherein the organic acid is at least one selected from acetic acid, methylsulfonic acid, sulfamic acid, and malonic acid.

6. The etchant of claim 1 or 2, wherein the chelating agent is selected from at least one of glycine diacetic acid, iminodiacetic acid, ethylenediamine tetraacetic acid, methylsulfonyl acetic acid, tranexamic acid, nitrilotriacetic acid, sarcosine, and glutamic acid.

7. The etchant according to claim 1 or 2, wherein the etching stabilizer is selected from at least one of ethylene glycol, triethylene glycol, propylene glycol, 1, 3-butanediol, and 1, 4-butanediol.

8. The etchant of claim 2, wherein the pH modifier is selected from at least one of sodium sulfate, potassium sulfate, sodium bisulfate, and potassium bisulfate.

9. A method of preparing an etchant, characterized in that the etchant according to any one of claims 1-8 is prepared with a composition;

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

preferably, the copper-containing alloy is a copper-molybdenum-niobium alloy.