Etching composition and use thereof

Abstract

The application discloses an etching composition and application thereof, which comprises, in mass percentage, 6.0-15.0% of hydrogen peroxide, 70.0-88.2% of water, 2.5-10.0% of a compound shown as formula (I), 0.5-5.0% of alkyl phenyl ether and / or alkoxy phenyl ether, 2.5-5.0% of a buffer system, and 0.3-1.0% of a chelating agent; R1 is C 1‑6 alkyl, phenyl or substituted phenyl, the substituent in the substituted phenyl is selected from hydroxyl and / or carboxyl; the buffer system is used for regulating the pH value of the etching system and does not contain fluorine, phosphorus and nitrogen, so that the change rate of the pH value of the etching system in etching is less than 1%; the etching composition is fluorine-free, phosphorus-free and low in nitrogen content, is good in environmental protection, can keep the etching angle stable, the loss of critical dimension reasonable and small in fluctuation, the etching speed ideal, and free from molybdenum residue and residue when etching a multilayer film layer containing copper and molybdenum.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of metal film layer etching solution for flat panel display, in particular to an environmentally friendly etching solution, and more particularly to a fluorine-free, phosphorus-free, low-nitrogen environmentally friendly etching solution and its application. BACKGROUND

[0002] In the current high-generation liquid crystal panel production process, the large size of the panel means that lower resistance-capacitance signal delay, shorter charging time, etc. are required, so high conductivity, better anti-electromigration ability of copper and its alloy materials are required on the wiring materials such as signal lines. The manufacturing method of copper-containing wiring is basically to deposit a copper-containing multilayer film on a glass substrate, and use photoresist as a mask to determine the required circuit pattern, and then etch with wet electronic chemicals. The aforementioned copper-containing multilayer film usually includes copper / molybdenum, copper / molybdenum / niobium, copper / molybdenum nitride, copper / molybdenum / nitride, etc. multilayer thin film, in order to overcome the problem of poor adhesion of copper to the glass substrate.

[0003] Currently, the copper etching solution products in the industry are mainly obtained by mixing hydrogen peroxide, acid, and additives. The copper etching solution based on hydrogen peroxide will produce a large amount of copper ions during the etching process, which will accelerate the decomposition of hydrogen peroxide and greatly increase the instability of the system. In order to maintain the stability of the etching solution and ensure the stability of the etching speed, a large amount of chelating agents or organic alcohol amines are usually added to the system. Chelating agents such as aminotriphosphonic acid, ethylenediaminetetraphosphonic acid, hexanediaminetetraphosphonic acid, diethylenetriamine pentaphosphonic acid, and dihexylenetriamine pentaphosphonic acid, and organic alcohol amines such as ethanolamine, diethanolamine, and triethanolamine, secondary amines, and tertiary amines, etc. Although good stability can be achieved in the etching system, the high nitrogen content in the system is not conducive to environmental protection.

[0004] At the same time, during the copper etching process, metal molybdenum layer residues often cause tailing phenomenon. The current solution is to add hydrofluoric acid or fluorine-containing salts such as potassium fluoride, ammonium fluoride, ammonium hydrogen fluoride, sodium fluoride, etc., or to add a large amount of organic amines such as ethanolamine, triethanolamine, dimethyl ethanolamine, and aminomethyl propanol to the system to solve the molybdenum residue problem as much as possible.

[0005] In addition, nitrogen azoles or homologous derivatives such as aminotetrazole, benzotriazole, and thiazole corrosion inhibitors are usually added to the existing etching solution to inhibit the reaction rate. These substances are usually toxic and difficult to degrade, and have a destructive effect on the environment and human health.

[0006] For example, CN101684557 discloses a copper, copper molybdenum alloy electrode etching liquid in a liquid crystal display system, which comprises 12 to 35% of hydrogen peroxide, 0.5 to 5% of phosphate, and 0.0001 to 0.5% of fluoride ion, 0.1 to 5% of a first water-soluble cyclic amine, 0.1 to 5% of a second water-soluble cyclic amine, 0.1 to 5% of a diol, and deionized water. The etching process for metal wires contains fluorine in the etching liquid, which is not conducive to environmental protection, and the post-processing pressure is large.

[0007] For example, CN113186531A discloses a fluorine-free etching liquid, which contains, by weight percentage, 1wt%-25wt% of hydrogen peroxide; 0.01wt%-3wt% of an etching stabilizer; 1wt%-20wt% of an etching inhibitor; 0.01wt%-4wt% of a pH regulator; 1wt%-10wt% of an auxiliary oxidizing agent; 0.01wt%-0.8wt% of an etching additive; and the rest is deionized water. Although the etching liquid does not contain fluorine, a large amount of alcohol amine, high-nitrogen or phosphorus-containing compounds are selected as additives, which is not conducive to environmental protection.

[0008] For example, CN112030165 discloses a copper molybdenum alloy layer etching liquid for TFT-LCD process, which is composed of the following raw materials with weight percentage: 5%-25% of hydrogen peroxide, 2%-4% of a chelating agent, 1%-2% of a regulator, 0.05%-0.5% of a stabilizer, 0.05%-0.5% of corrosion inhibitor A, 0.05%-0.5% of corrosion inhibitor B, 0.5%-1% of a multifunctional additive, and the rest is ultrapure water. The chelating agent is an organic phosphonic acid containing N atoms, selected from at least one of aminotrimethylene phosphonic acid, ethylenediamine tetramethylene phosphonic acid, hexanediamine tetramethylene phosphonic acid, diethylenetriamine pentamethylene phosphonic acid, dihexylenetriamine pentamethylene phosphonic acid, and polyamino polyether methyl phosphonic acid. The regulator is phosphonyl butane tricarboxylic acid. The stabilizer is phenyl urea, thiourea, and / or phenylacetamide. The corrosion inhibitor A is triethanolamine borate. The corrosion inhibitor B is a nitrogen-containing heterocyclic compound, selected from at least one of imidazole, pyridine, cinnoline, aminobenzothiazole, and 5-amino tetrazole. The multifunctional additive is imino disuccinic acid tetrasodium. Although the etching liquid has relatively good etching effect, a large amount of nitrogen and phosphorus-containing substances are used in the formula, which is not conducive to environmental protection.

[0009] The amount of copper etching liquid is huge, and most of the existing etching liquid components contain a large amount of phosphorus, fluorine, nitrogen and other structural components. The treatment of waste liquid after etching brings great challenges. Panel display factories have put forward the requirements of fluorine-free, phosphorus-free and low-nitrogen etching liquid. SUMMARY

[0010] The present application aims to overcome one or more deficiencies of the prior art, and provide an improved etching composition which can maintain stable etching angle, reasonable and small fluctuation of critical dimension loss, ideal etching speed, and no molybdenum residue and residue on the basis of fluoride-free, phosphorus-free and low-nitrogen environmental protection.

[0011] The present application also provides an application of the above etching composition in etching a multi-layer film layer containing copper and molybdenum, which includes but is not limited to multi-layer film layers such as copper / molybdenum, copper / molybdenum / niobium, copper / molybdenum nitride, copper / molybdenum / nitride, etc.

[0012] To achieve the above-mentioned purpose, the present application adopts a technical solution of:

[0013] An etching composition, comprising a) hydrogen peroxide, b) water, c) a compound represented by formula (I):

[0014] R1 is C 1-6 alkyl, phenyl or substituted phenyl, the substituents in the substituted phenyl being selected from hydroxyl and / or carboxyl;

[0015] d) alkyl phenyl ether and / or alkoxy phenyl ether;

[0016] e) a buffer system for regulating the pH value of the etching system and containing no fluoride, phosphorus and nitrogen, so that the change rate of the pH value of the etching system in etching is less than 1%;

[0017] f) a chelating agent;

[0018] In terms of mass percentage, in the etching composition, a) hydrogen peroxide is 6.0%-15.0%, b) water is 70.0%-88.2%, c) the compound represented by formula (I) is 2.5%-10.0%, d) alkyl phenyl ether and / or alkoxy phenyl ether is 0.5%-5.0%, e) the buffer system is 2.5%-5.0%, and f) the chelating agent is 0.3%-1.0%.

[0019] Further, in terms of mass percentage, in the etching composition, a) hydrogen peroxide accounts for 6.0%-12.0%.

[0020] Further, in terms of mass percentage, in the etching composition, c) the compound represented by formula (I) accounts for 2.5%-8.0%. In some embodiments, in terms of mass percentage, in the etching composition, c) the compound represented by formula (I) accounts for 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, etc.

[0021] Further, the alkyl phenyl ether and / or alkoxy phenyl ether d) is present in the etching composition in an amount of 0.5% to 4.0% by mass. In some embodiments, the alkyl phenyl ether and / or alkoxy phenyl ether d) is present in the etching composition in an amount of 0.5%, 0.8%, 1.0%, 1.2%, 1.5%, 1.8%, 2.0%, 2.5%, 3.0%, 3.5%, etc. by mass.

[0022] Further, the buffer system e) is present in the etching composition in an amount of 2.5% to 4.5% by mass. In some embodiments, the buffer system e) is present in the etching composition in an amount of 2.6%, 2.8%, 3.0%, 3.2%, 3.6%, 3.8%, 4.0%, 4.2%, etc. by mass.

[0023] In some embodiments of the present application, component b) is pure water.

[0024] In some embodiments of the present application, the hydrogen peroxide can be added by adding an aqueous hydrogen peroxide solution, which can be 30% to 50%, etc. When added in the form of an aqueous hydrogen peroxide solution, the amount of hydrogen peroxide can be calculated according to the formula amount to add an appropriate amount of aqueous hydrogen peroxide solution.

[0025] According to some preferred aspects of the present application, R1is methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, neopentyl, phenyl, hydroxyphenyl (which can be, for example, ), carboxyphenyl (which can be, for example, ), or salicylic acid group

[0026] In some embodiments of the present application, the compound of formula (I) can be selected from phenol sulfonic acid (including o-phenol sulfonic acid, m-phenol sulfonic acid, p-phenol sulfonic acid), methyl sulfonic acid, 5-sulfo salicylic acid, etc.

[0027] According to some preferred aspects of the present application, the alkyl phenyl ether is selected from a compound of formula (II), the structural formula of which is:

[0028]

[0029] R2is C 1-6 alkyl, alkoxy or hydroxy-substituted C 1-6 alkyl, alkoxy or hydroxy-substituted C

[0030] In some embodiments of the present application, R2is methoxy, ethoxy, propoxy, isopropoxy, hydroxy-substituted methoxy, hydroxy-substituted ethoxy, hydroxy-substituted propoxy, hydroxy-substituted isopropoxy, etc.

[0031] According to some preferred aspects of the present application, the alkoxy phenyl ether is selected from the group consisting of compounds of formula (III), the structural formula of which is:

[0032]

[0033] R3 is C 1-6 alkylene, R4 is C 1-6 alkyl or hydroxy-substituted C 1-6 alkyl.

[0034] In some embodiments of the present application, R3 is methylene, ethylene, propylene, isopropylene, etc., and R4 is methyl, ethyl, propyl, isopropyl, hydroxy-substituted methyl, hydroxy-substituted ethyl, hydroxy-substituted propyl, hydroxy-substituted isopropyl, etc.

[0035] According to some preferred and specific aspects of the present application, component d) is selected from the group consisting of combinations of one or more of o-dioxane, o-diethyl ether, o-dipropyl ether, 2-hydroxyphenyl propyl ether, 2-hydroxyphenyl ethyl ether, 2-hydroxyphenyl methyl ether, 3-hydroxyphenyl propyl ether, 3-hydroxyphenyl ethyl ether, 3-hydroxyphenyl methyl ether, p-hydroxyphenyl propyl ether, p-hydroxyphenyl ethyl ether, p-hydroxyphenyl methyl ether, diethylene glycol monophenyl ether, ethoxyphenyl ether, and propoxyphenyl ether.

[0036] According to some preferred and specific aspects of the present application, the buffer system is used to regulate the pH value of the etching system to be always 2.5-3.5.

[0037] According to the present application, the etching composition does not contain fluorine and phosphorus.

[0038] According to some preferred aspects of the present application, the buffer system is composed of acetic acid and acetic acid salt capable of being dissolved in water, and the feeding molar ratio of the acetic acid to the acetic acid salt is 1:0.25-1.35.

[0039] Further, the acetic acid salt is sodium acetate and / or potassium acetate.

[0040] In some embodiments of the present application, the buffer system is composed of acetic acid and potassium acetate, and the feeding mass ratio of the acetic acid to the potassium acetate is 7:3-7:15.

[0041] In some embodiments of the present application, the chelating agent is selected from the group consisting of combinations of one or more of iminodiacetic acid, nitrilotriacetic acid, ethanedioic acid tetraacetic acid, tetrahydroxypropyl ethylenediamine, and aminoacetic acid.

[0042] The present application further provides another technical solution: a preparation method of the above-mentioned etching composition, which comprises the following steps: mixing the components of the etching composition, and obtaining the etching composition.

[0043] In some embodiments of the present application, the mixing method can be stirring or oscillation, etc.

[0044] In some embodiments of the present application, the hydrogen peroxide is added in the form of an aqueous hydrogen peroxide solution (hydrogen peroxide water), and the preparation method of the etching composition comprises: mixing, dispersing and dissolving the components in the formula except the aqueous hydrogen peroxide solution, adding the aqueous hydrogen peroxide solution after uniform stirring, and mixing uniformly to prepare.

[0045] The present application further provides another technical solution: application of the etching composition described above in etching a multilayer film layer containing copper and molybdenum.

[0046] Thanks to the above technical solution, the present application has the following advantages compared with the prior art:

[0047] The present application uses a new formula system to make the components play a synergistic role, and uses the system's own balance adjustment to control the etching rate without using azoles and their derivatives and other harmful inhibitors to the human body. In the etching period with 0 ppm to 6000 ppm of copper ions, the etching angle is kept at 40-55℃ with small fluctuations, the single side CD loss (critical dimension loss) is controlled at 0.75-0.85 microns and has good stability, there is no molybdenum residue, and there is no residue.

[0048] In addition, the etching composition of the present application is fluorine-free, phosphorus-free and low-nitrogen, and has good environmental protection, reducing the pressure of wastewater treatment. BRIEF DESCRIPTION OF DRAWINGS

[0049] Fig. 1 The scanning electron microscope cross-sectional view of the glass substrate etched by the etching composition prepared in Example 1 of the present application with 0 ppm of copper ions;

[0050] Fig. 2 The scanning electron microscope cross-sectional view of the glass substrate etched by the etching composition prepared in Example 1 of the present application with 2000 ppm of copper ions;

[0051] Fig. 3 The scanning electron microscope cross-sectional view of the glass substrate etched by the etching composition prepared in Example 1 of the present application with 4000 ppm of copper ions;

[0052] Fig. 4 The scanning electron microscope cross-sectional view of the glass substrate etched by the etching composition prepared in Example 1 of the present application with 6000 ppm of copper ions. DETAILED DESCRIPTION

[0053] The main concept of the present application is that: through the overall concept of the formula, the components interact with each other in the system to achieve synergistic effect, and a single component achieves multiple functions; the combination of the compound represented by formula (I) and hydrogen peroxide in the formula can corrode the multi-layer film layer containing copper and molybdenum, participate in the reaction with copper oxide, assist the complexation of part of the generated copper ions, and is beneficial to etching the molybdenum layer to prevent the formation of molybdenum tail; the addition of alkyl phenyl ether and / or alkoxy phenyl ether in the system can inhibit the decomposition of hydrogen peroxide due to excessive activation, and can also undertake the role of complexing part of the copper ions, and can also adjust the viscosity of the system to synergistically control the stability of the etching rate in the etching period; the pH value of the etching system is regulated by the buffer system without fluorine, phosphorus and nitrogen, which ensures the stability of the etching system, and the amount of chelating agent can be significantly reduced by the synergistic complexation of copper ions by multiple components in the formula, thereby greatly reducing the concentration of nitrogen atoms in the system; in addition, the entire etching system is balanced and adjusted by the combination of components, and does not need to use azole and its derivatives and other harmful corrosion inhibitors to control the etching rate.

[0054] Based on the above concept, the present application provides an etching composition, which comprises a) hydrogen peroxide, b) water, c) a compound represented by formula (I): R1 is C 1-6 alkyl, phenyl or substituted phenyl, the substituent in the substituted phenyl being selected from hydroxyl and / or carboxyl; d) alkyl phenyl ether and / or alkoxy phenyl ether; e) a buffer system for regulating the pH value of the etching system and not containing fluorine, phosphorus and nitrogen, so that the change rate of the pH value of the etching system is less than 1% in etching; f) a chelating agent.

[0055] Further, in the system of the present application, the mass percentage content of component a) hydrogen peroxide is preferably 6.0%-15.0%, and practice shows that if the content is less than 6%, the oxidation of metal is insufficient and the etching rate is low, but if the content of hydrogen peroxide is higher than 15%, the significant increase of copper ions will cause the chain decomposition of hydrogen peroxide, and the system is unstable.

[0056] Further, in the system of the present application, the mass percentage content of component c) the compound represented by formula (I) is preferably 2.5%-10.0%, and if the content is less than 2.5%, the etching rate may be affected and the reaction is slow, and the molybdenum residue is obvious; if the content is too high, on the one hand, the reaction rate is too fast and the single CD loss is not easy to control, and on the other hand, the pH value is too low, which is not conducive to the complexation of copper ions.

[0057] Further, the mass percentage content of component d) alkyl phenyl ether and / or alkoxy phenyl ether in the system of the present application is preferably 0.5%-5.0%. If the content is too low, the decomposition rate of hydrogen peroxide is accelerated, which leads to the risk of explosive boiling of the system, and their solubility in the system is limited. If the content is too high, the etching solution is not soluble, which easily causes instability of the system.

[0058] Further, the mass percentage content of component e) buffer system in the system of the present application is preferably 2.5%-5.0%. If the content is too low, the pH value is not stable at the end of etching, the pH value change rate is higher than 5%, and the etching speed fluctuation is large. If the content of the buffer system is too high, the cost is increased unnecessarily. Preferably, in the system of the present application, acetic acid and acetate such as potassium acetate system are preferably selected, which do not contain fluorine, phosphorus and nitrogen, and the feeding molar ratio of them is preferably controlled to be 1:0.25-1.35 (when the acetate is potassium acetate, the weight ratio is controlled to be 7:3-7:15), and the content is about 2.5%-5%. The pH value of the system can be stabilized at about 2.5-3.5, for example, about 3, by using acetic acid and potassium acetate. Even at the end of etching, a large amount of copper ions is dissolved into the etching system, the overall pH value change rate is less than 1%, which ensures the stability of the system from the beginning to the end, and the need for adding a large amount of alcohol amine such as primary amine, secondary amine, tertiary amine and other raw materials with high nitrogen content in the previous etching system is avoided.

[0059] Further, the main function of the chelating agent in the system of the present application is to complex copper ions, which on the one hand reduces the decomposition of hydrogen peroxide, and on the other hand prevents the production of etching residues caused by excessive copper ions. By the overall linkage of the components in the present application, the amount of chelating agent is significantly reduced, the nitrogen atom concentration is greatly reduced, the nitrogen atom content is controlled to be within 1200 ppm, and the pressure of wastewater treatment is further reduced. The content of the chelating agent can be controlled to be 0.3%-1%. If the content of the chelating agent is too low, it is not conducive to the complexation of copper ions, and etching residues may appear. If the content of the chelating agent is too high, the system does not change, which causes unnecessary waste.

[0060] The above scheme is further described in combination with specific examples. It should be understood that these examples are used to illustrate the basic principles, main features and advantages of the present application, and the present application is not limited in scope by the following examples. The implementation conditions used in the examples can be further adjusted according to specific requirements. The implementation conditions not mentioned are usually the conditions in conventional experiments.

[0061] The purity of the raw materials used in the following examples and comparative examples is analytical pure and above. When not specially mentioned, all raw materials can come from commercial sources or be prepared by conventional methods in the art.

[0062] Example 1

[0063] The example provides an etching composition and a preparation method thereof, the etching composition comprising, in mass percentage, 8% of hydrogen peroxide, 3% of o-phenolsulfonic acid, 1% of o-dianisole, 3.5% of a buffer system, 0.5% of iminodiacetic acid, and the balance being water; wherein the buffer system is composed of acetic acid and potassium acetate, the mass ratio of acetic acid to potassium acetate is 7:10, and the hydrogen peroxide is added in the form of a 30% hydrogen peroxide aqueous solution (hydrogen peroxide water).

[0064] The preparation method of the etching composition comprises the following steps: mixing and dispersing and dissolving all the components in the formula except the hydrogen peroxide aqueous solution, stirring uniformly, adding the hydrogen peroxide aqueous solution, and mixing uniformly to obtain the etching composition.

[0065] Example 2

[0066] The example is basically the same as example 1, except that the iminodiacetic acid is replaced by an equivalent amount of nitrilotriacetic acid.

[0067] Example 3

[0068] The example is basically the same as example 1, except that the o-phenolsulfonic acid is replaced by an equivalent amount of methylsulfonic acid.

[0069] Example 4

[0070] The example is basically the same as example 1, except that the o-phenolsulfonic acid is replaced by an equivalent amount of 5-sulfosalicylic acid.

[0071] Example 5

[0072] The example is basically the same as example 3, except that the mass ratio of acetic acid to potassium acetate is 7:13.

[0073] Example 6

[0074] The example is basically the same as example 1, except that the amount of the buffer system is adjusted to 4.5%, and the amount of water is correspondingly reduced.

[0075] Example 7

[0076] The example is basically the same as example 1, except that the o-phenolsulfonic acid is replaced by an equivalent amount of ethylsulfonic acid.

[0077] Example 8

[0078] The example is basically the same as example 1, except that the o-dianisole is replaced by an equivalent amount of 2-hydroxypropyl ether.

[0079] Example 9

[0080] The example is basically the same as example 1, except that the o-dianisole is replaced by an equivalent amount of diethylene glycol monophenyl ether.

[0081] Example 10

[0082] Essentially the same as Example 1, with the difference that the o-dianisole is replaced by an equivalent amount of propyloxyphenyl ether.

[0083] Example 11

[0084] Essentially the same as Example 1, with the difference that the o-dianisole is replaced by an equivalent amount of ethyloxyphenyl ether.

[0085] Example 12

[0086] Essentially the same as Example 1, with the difference that the amount of hydrogen peroxide is adjusted to 10%, with a corresponding reduction in the amount of water.

[0087] Example 13

[0088] Essentially the same as Example 1, with the difference that the amount of o-phenolsulfonic acid is adjusted to 5%, with a corresponding reduction in the amount of water.

[0089] Example 14

[0090] Essentially the same as Example 1, with the difference that the amount of o-dianisole is adjusted to 2%, with a corresponding reduction in the amount of water.

[0091] Comparative Example 1

[0092] Essentially the same as Example 1, with the difference that the o-phenolsulfonic acid is replaced by an equivalent amount of citric acid.

[0093] Comparative Example 2

[0094] Essentially the same as Example 1, with the difference that the o-phenolsulfonic acid is replaced by an equivalent amount of sulfuric acid at a concentration of 98%.

[0095] Comparative Example 3

[0096] Essentially the same as Example 1, with the difference that the o-dianisole is replaced by an equivalent amount of polyethylene glycol.

[0097] Comparative Example 4

[0098] Essentially the same as Example 1, with the difference that the amount of iminodiacetic acid is reduced to 0.1%, with a corresponding increase in the amount of water.

[0099] Comparative Example 5

[0100] Essentially the same as Example 1, with the difference that the amount of o-phenolsulfonic acid is reduced to 1%, with a corresponding increase in the amount of water.

[0101] Comparative Example 6

[0102] The method is basically the same as in Example 1, except that the content of the buffer system is reduced to 1.5%, and the amount of water added is increased accordingly.

[0103] Comparative Example 7

[0104] The process is basically the same as in Example 1, except that the mass ratio of acetic acid to potassium acetate is 7:20.

[0105] Comparative Example 8

[0106] The process is basically the same as in Example 1, except that the mass ratio of acetic acid to potassium acetate is 7:1.

[0107] Comparative Example 9

[0108] The method is basically the same as in Example 1, except that the amount of o-phenylenedimethyl ether added is reduced to 0 and the amount of water added is increased accordingly.

[0109] Comparative Example 10

[0110] The method is basically the same as in Example 1, except that the amount of o-phenylenedimethyl ether added is reduced to 0.1%, and the amount of water added is increased accordingly.

[0111] Performance testing

[0112] Substrate fabrication: Sequentially depositing layers with a thickness of [thickness value missing] on a glass substrate. molybdenum layer and A copper layer is deposited to form a copper-molybdenum bilayer film. Photoresist is coated on the deposited film layer, and exposure and development are performed to form a photomask. The copper-molybdenum bilayer film not covered by the photomask is then etched using the etching compositions prepared in Examples 1-14 and Comparative Examples 1-10.

[0113] Etching Experiment: 1 L each of the etching compositions prepared in Examples 1-14 and Comparative Examples 1-10 were added to a beaker. The temperature was maintained at 30°C, and the stirring speed was set to 250 r / min. The substrate was cut into 10 cm * 10 cm pieces and immersed in the etching solution. The etching time was set to 120 s. After etching, the substrate was immediately rinsed with pure water and air-dried. The cross-sectional shape, etching angle, CD loss, molybdenum residue, and slag were confirmed using a scanning electron microscope (SEM, Hitachi S4800). The remaining proportion of hydrogen peroxide before and after the reaction was determined by acid-base titration. The hydrogen peroxide decomposition rate was calculated as (content of new hydrogen peroxide solution - content of old hydrogen peroxide solution) / content of new hydrogen peroxide solution * 100%.

[0114] To simulate a production line, copper powder was added at a rate of 1000 ppm per hour to the etching compositions prepared in Examples 1-14 and Comparative Examples 1-10. The etching process was repeated at 2000 ppm, 4000 ppm, and 6000 ppm to test the glass substrate.

[0115] The scanning electron microscope cross-sectional view of the etched glass substrate is shown in Figure 1, where the copper ion concentration in the etching composition prepared in Example 1 is 0 ppm, 2000 ppm, 4000 ppm, and 6000 ppm, respectively. Figs. 1-4 .

[0116] Evaluation results

[0117] The results of the etching compositions prepared in Examples 1-14 and Comparative Examples 1-10 in etching are shown in Tables 1 and 2.

[0118] Table 1

[0119]

[0120]

[0121] Table 2

[0122]

[0123]

[0124] In Comparative Example 1, the phenol sulfonic acid is replaced by citric acid in the same amount, and in this etching system, the copper ion chelating ability is insufficient in the middle and later stages of etching, the hydrogen peroxide decomposition rate is significantly increased, the CD loss is reduced, the etching angle is increased, and molybdenum residues and etching residues appear.

[0125] In Comparative Example 2, the phenol sulfonic acid is replaced by 98% sulfuric acid in the same amount, and in this etching system, the etching rate is too large, and molybdenum residues and etching residues appear from the beginning, and the hydrogen peroxide decomposition rate is too high at the end.

[0126] In Comparative Example 3, the o-phenyl dimethyl ether is replaced by polyethylene glycol in the same amount, and the etching angle and CD loss fluctuate greatly, the hydrogen peroxide decomposition rate is high at the end, and molybdenum residues and etching residues appear.

[0127] In Comparative Example 4, the chelating agent IDA content is 0.1%, the copper ion chelating ability is insufficient in the middle and later stages of etching, the hydrogen peroxide decomposition rate is significantly accelerated, the etching rate is reduced, the CD loss is reduced, the etching angle is increased, and molybdenum residues and etching residues appear.

[0128] In Comparative Example 5, the o-phenol sulfonic acid content is 1%, the etching solution acidity is insufficient, and the CD loss and etching angle fluctuate greatly throughout the etching period.

[0129] In Comparative Examples 6, 7, and 8, the buffer acetic acid and potassium acetate content is insufficient or the buffer ratio is not matched, the pH value is unstable throughout the etching period, which leads to an increase in the hydrogen peroxide decomposition rate, a large fluctuation in the CD loss and etching angle, and the presence of molybdenum residues and residues.

[0130] Comparative examples 9 and 10 do not add stabilizer o-dimethyl phenyl ether or content of 0.1%, hydrogen peroxide is activated and cannot be effectively inhibited, hydrogen peroxide is decomposed violently, CD loss and etching angle fluctuation is huge, system is out of control.

[0131] From the above comparative example and example results, it can be seen that the copper-molybdenum etching liquid system of the present application not only eliminates the use of phosphorus and fluorine raw materials, but also greatly reduces the input of nitrogen-containing raw materials. Moreover, the comprehensive coordination of each component will cause etching data defects if any component is missing or the content is not matched.

[0132] The above examples are only for illustrating the technical concept and characteristics of the present application, the purpose is to enable those skilled in the art to understand the content of the present application and to implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made in accordance with the spirit and essence of the present application should be covered within the protection scope of the present application.

[0133] The endpoints of the ranges and any values disclosed herein are not limited to the precise values recited as the exact dimensions are not considered critical for the present application. The endpoints of the ranges of values and the values of the ranges themselves should be understood to be approximate. The exact numerical values of the endpoints of the ranges and the individual points of the ranges can be combined with each other to form new ranges of values, which are to be understood as being specifically disclosed herein.

Claims

1. An etching composition comprising a) hydrogen peroxide and b) water, characterized in that, The etching composition also includes: c) The compound shown in formula (Ⅰ) has the following structural formula: R1 is C 1-6 Alkyl, phenyl, or substituted phenyl, wherein the substituents in the substituted phenyl are selected from hydroxyl and / or carboxyl groups; d) Alkylphenyl ethers and / or alkoxyphenyl ethers; e) A buffer system, used to regulate the pH value of the etching system and free of fluorine, phosphorus and nitrogen, so that the pH value of the etching system changes by less than 1% during etching; the buffer system is composed of acetic acid and water-soluble acetate, and the molar ratio of acetic acid to acetate is 1:0.25-1.

35. f) Chelating agents; By mass percentage, the etching composition contains: a) 6.0%-15.0% hydrogen peroxide, b) 70.0%-88.2% water, c) 2.5%-10.0% of the compound shown in formula (I), d) 0.5%-5.0% alkylphenyl ethers and / or alkoxyphenyl ethers, e) 2.5%-5.0% buffer system, and f) 0.3%-1.0% chelating agent.

2. The etching composition according to claim 1, characterized in that, R1 can be methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, phenyl, hydroxyphenyl, carboxyphenyl, or salicylic acid.

3. The etching composition according to claim 1, characterized in that, The alkylphenyl ether is selected from the compound shown in formula (II), and the structural formula of the compound shown in formula (II) is: ， R2 is C 1-6 alkoxy or hydroxy substituted C 1-6 Alkoxy group, where t is 1, 2, 3 or 4.

4. The etching composition according to claim 1, characterized in that, The alkoxyphenyl ether is selected from the compound shown in formula (III), and the structural formula of the compound shown in formula (III) is: ， R3 is C 1-6 Alkylene, R4 is C 1-6 alkyl or hydroxy substituted C 1-6 alkyl.

5. The etching composition according to claim 1, 3, or 4, characterized in that, Component d) is selected from one or more combinations of phthalic acid dimethyl ether, phthalic acid diethyl ether, phthalic acid dipropyl ether, 2-hydroxyphenylpropionate ether, 2-hydroxyphenylethyl ether, 2-hydroxyanisole, 3-hydroxyphenylpropionate ether, 3-hydroxyphenylethyl ether, 3-hydroxyanisole, p-hydroxyphenylpropionate, p-hydroxyphenylethyl ether, p-hydroxyanisole, diethylene glycol monophenyl ether, ethoxybenzene, and propoxybenzene.

6. The etching composition according to claim 1, characterized in that, The buffer system is used to control the pH of the etching system to always be 2.5-3.5; and / or, the etching composition is free of fluorine and phosphorus.

7. The etching composition according to claim 1, characterized in that, The acetate is sodium acetate and / or potassium acetate.

8. The etching composition according to claim 1, characterized in that, The chelating agent is selected from one or more combinations of iminodiacetic acid, azirtriacetic acid, oxalatetetraacetic acid, tetrahydroxypropylethylenediamine, and aminoacetic acid.

9. The use of the etching composition according to any one of claims 1-8 in etching a multilayer film containing copper and molybdenum.

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