Copper-molybdenum metal etching liquid composition and preparation method thereof

Abstract

The present invention discloses a copper-molybdenum metal etching liquid composition, and the raw materials for preparing the composition include a main agent and an auxiliary agent, including hydrogen peroxide, an organic acid, an amino base, a stabilizer, an electrochemical inhibitor, an alcohol additive, and a solvent. The present invention adopts ethylene glycol and an electrochemical inhibitor to synergize, reduce the surface tension between the etching solution and the metal film layer, enhance the adhesion rate of the etching solution and the metal film layer, and can perfectly solve the chamfering problem in the etching process. And by using isobutanolamine and triethanolamine as amino base I, copper ions can be complexed, the decomposition rate of hydrogen peroxide can be stabilized, the etching rate balance can be maintained, and a good etching morphology can be achieved, with excellent Taper angle, CD-Bais, and small variation, so that it can load a copper ion concentration of 12000ppm, and the lower limit of molybdenum residue reaches 0.45μm, with an excellent etching range, meeting the impact of customer process fluctuations on production, and being environmentally friendly, and the cost of waste liquid treatment is low.

Description

Technical Field

[0001] The invention relates to a copper-molybdenum metal etching liquid composition, in particular to C23F, and in particular to the field of removing metal materials on a surface by a non-mechanical method. Background Art

[0002] Copper-molybdenum film is an important component used in liquid crystal display devices. Copper materials have low resistivity, and molybdenum materials have good adhesion to glass and other substrates. Therefore, the quality of copper-molybdenum film greatly affects the quality of liquid crystal display devices. Copper-molybdenum etching liquid with good performance has a good effect on the etching of copper-molybdenum film, which can form a good etching morphology and reduce the generation of chamfers. The existing etching liquid on the market contains fluorine, phosphorus and other components, which will have a great impact on the health of operators during the use and processing, and there are also environmental problems. In addition, if the concentration of copper ions in the etching liquid is too high, it will affect the etching rate and etching effect. The copper ion concentration that can be loaded by the existing etching liquid is relatively low.

[0003] Chinese invention patent CN202011490580.9 discloses a copper-molybdenum metal etching liquid and its preparation method and application. By selecting specific components and ratios, a copper-molybdenum etching liquid is obtained, which can cooperate with metal complexing agents to control the etching speed, without molybdenum tailing and residue, but the use of fluorine-containing components in the formula will cause certain environmental pressure. Chinese invention patent CN202010090863.8 discloses an etching liquid, additives and a method for making metal wiring. It does not use fluorides and achieves an etching angle suitable for the etching angle and less metal residue. However, the maximum copper ion concentration it can carry is 6000ppm. Exceeding the limited concentration range will lead to a decrease in the etching effect. Summary of the invention

[0004] In order to improve the etching morphology of the copper-molybdenum film layer in the etching solution, increase the copper ion loading concentration of the etching solution, and reduce environmental pressure, the first aspect of the present invention provides a copper-molybdenum metal etching solution composition, and the preparation raw materials include a main agent and an auxiliary agent, the main agent includes hydrogen peroxide, an organic acid I, an amino base I, a stabilizer I, an electrochemical inhibitor I, an alcohol additive, and a solvent, and the auxiliary agent includes an organic acid II, an amino base II, a stabilizer II, an electrochemical inhibitor II, and a solvent.

[0005] As a preferred embodiment, the amount of the main agent and the auxiliary agent added is 1%-1.5% of the weight of the main agent for every 1000 ppm increase in copper ions.

[0006] As a preferred embodiment, the amino bases I and II are both selected from one or a combination of alkyl diamines, alkyl alcohol amines, amino alkyl amines, and hydroxymethyl amino alkanes.

[0007] As a preferred embodiment, the alkyl alcohol amine is selected from one or a combination of triethanolamine, N-butyldiethanolamine, methyldiethanolamine, ethylethanolamine, diisopropanolamine, triisopropanolamine, dibutanolamine, and isobutanolamine.

[0008] As a preferred embodiment, the amino base I is a combination of isobutanolamine and triethanolamine. Preferably, the weight ratio of isobutanolamine to triethanolamine is (2-5): (3-5).

[0009] As a preferred embodiment, the weight ratio of isobutanolamine to triethanolamine is 5:2.

[0010] As a preferred embodiment, the amino base II is diethylaminopropylamine.

[0011] As a preferred embodiment, the organic acids I and II are both selected from one or a combination of alkyl dibasic acid, fruit acid, iminodiacetic acid, and nitrilotriacetic acid.

[0012] As a preferred embodiment, the organic acid I is a combination of malonic acid and malic acid. Preferably, the weight ratio of malonic acid to malic acid is (5-6): (1-3).

[0013] As a preferred embodiment, the weight ratio of malonic acid to malic acid is 5:3.

[0014] As a preferred embodiment, the organic acid II is malonic acid.

[0015] As a preferred embodiment, the alcohol additive is a polyol. Preferably, the polyol is selected from one or a combination of ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, hexanediol, neopentyl glycol, and dipropylene glycol.

[0016] As a preferred embodiment, the alcohol additive is ethylene glycol.

[0017] As a preferred embodiment, the electrochemical inhibitors I and II are both azole compounds, selected from 3-aminotriazole, 5-aminotetrazolyl, or a combination of the two.

[0018] As a preferred embodiment, the electrochemical inhibitor I is a combination of 3-aminotriazole and 5-aminotetrazolyl. Preferably, the weight ratio of the 3-aminotriazole to 5-aminotetrazolyl is (0.05-0.15): (0.05-0.15).

[0019] As a preferred embodiment, the weight ratio of 3-aminotriazole to 5-aminotetrazolyl is 0.1:0.1.

[0020] As a preferred embodiment, the electrochemical inhibitor II is 3-aminotriazole.

[0021] During the experiment, the applicant found that different metal film layers are prone to serious chamfering problems due to electrochemical effects, especially between copper-molybdenum film structures, which is more likely to cause bottom chamfering, causing climbing and breaking, affecting the etching yield. In addition, in high-concentration copper ion etching, due to the high copper ion concentration, the etching rate will drop significantly, causing serious molybdenum residue. The applicant found that by introducing ethylene glycol and electrochemical inhibitors Ⅰ3-aminotriazole and 5-aminotetrazolyl synergistically, the chamfering problem can be perfectly solved, a good etching morphology can be formed, and the lower limit of molybdenum residue reaches 0.45μm. The reason is that the introduction of ethylene glycol can reduce interfacial tension, enhance the adhesion rate of the solution, solve the chamfering problem in the etching process, and form a good etching morphology. In addition, the synergistic effect of 3-aminotriazole and 5-aminotetrazolyl can inhibit the etching of copper metal, adjust the etching rate ratio between different film layers, and further improve the chamfering problem in etching, which is especially suitable for copper-molybdenum etching with high copper ion concentration.

[0022] As a preferred embodiment, the stabilizers I and II are both selected from one of phenylurea, p-hydroxybenzenesulfonic acid, ethanol, propanol, or a combination of the two.

[0023] As a preferred embodiment, the stabilizers I and II are both phenylurea.

[0024] As a preferred embodiment, the preparation raw materials include, by weight percentage: the main agent is hydrogen peroxide 3-15%, organic acid I 1-15%, amino base I 1-15%, stabilizer I 0.01-1%, electrochemical inhibitor I 0.01-1%, alcohol additives 1-10%, and solvents make up the balance; the auxiliary agents include organic acid II 10-40%, amino base II 10-40%, stabilizer II 0.01-2%, electrochemical inhibitor II 0.01-1%, and solvents make up the balance.

[0025] As a preferred embodiment, the preparation raw materials include, by weight percentage: the main agent is 6-12% hydrogen peroxide, 2-10% organic acid I, 3-10% amino base I, 0.05-0.5% stabilizer I, 0.03-0.8% electrochemical inhibitor I, 4-8% alcohol additives, and the solvent makes up the balance; the auxiliary agent includes 10-25% organic acid II, 10-20% amino base II, 0.05-0.5% stabilizer II, 0.03-0.5% electrochemical inhibitor II, and the solvent makes up the balance.

[0026] As a preferred embodiment, the preparation raw materials include, by weight percentage: the main agent is 8% hydrogen peroxide, 8% organic acid I, 7% amino base I, 0.1% stabilizer I, 0.2% electrochemical inhibitor I, 4% alcohol additives, and the balance is made up of solvent; the auxiliary agent includes 20% organic acid II, 13% amino base II, 0.1% stabilizer II, 0.5% electrochemical inhibitor II, and the balance is made up of solvent.

[0027] A second aspect of the present invention provides a method for preparing a copper-molybdenum metal etching solution composition, comprising the following steps:

[0028] (1) Mix the main agent raw materials uniformly according to weight percentage;

[0029] (2) mixing the auxiliary raw materials uniformly according to weight percentage;

[0030] (3) Add the auxiliary agent to the main agent and mix them evenly for etching reaction.

[0031] As a preferred embodiment, for every 1000 ppm increase in copper ions in the etching solution, 1.05% of the weight of the main agent is added to the system.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) The copper-molybdenum metal etching solution composition of the present invention adopts the synergistic effect of ethylene glycol and electrochemical inhibitor to reduce the surface tension between the etching solution and the metal film layer, enhance the adhesion rate of the etching solution and the metal film layer, and can perfectly solve the chamfering problem in the etching process.

[0034] (2) The copper-molybdenum metal etching liquid composition of the present invention can complex copper ions by using isobutanolamine and triethanolamine as amino base I, stabilize the decomposition rate of hydrogen peroxide, maintain the etching rate balance, achieve good etching morphology, have excellent Taper angle, CD-Bais, and small variation, so that it can load 12000ppm copper ion concentration, and at the same time, the lower limit of molybdenum residue reaches 0.45μm, with an excellent etching range, which meets the impact of customer process fluctuations on production.

[0035] (3) The copper-molybdenum metal etching liquid composition of the present invention adopts malic acid and malonic acid as organic acid I to cooperate with hydrogen peroxide, so that the etching liquid has a good etching effect without introducing fluorine and phosphide, is environmentally friendly, and has a low waste liquid treatment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is an electron microscope image of the etching effect after treatment with the etching solution composition of the present application. DETAILED DESCRIPTION

[0037] The present invention is described in detail below by way of examples. It is necessary to point out here that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by professionals and technicians in this field based on the content of the present invention above still belong to the scope of protection of the present invention.

[0038] In addition, unless otherwise stated, all raw materials used were commercially available.

[0039] Example 1

[0040] A copper-molybdenum metal etching liquid composition is prepared by raw materials, which include, by weight percentage: a main agent of 8% hydrogen peroxide, 8% organic acid I, 7% amino base I, 0.1% stabilizer I, 0.2% electrochemical inhibitor I, 4% alcohol additives, and a solvent to make up the balance; the auxiliary agent includes 20% organic acid II, 13% amino base II, 0.1% stabilizer II, 0.5% electrochemical inhibitor II, and a solvent to make up the balance.

[0041] The addition amount of the main agent and the auxiliary agent is 1:1.

[0042] The amino base I is a combination of isobutanolamine and triethanolamine, with a weight ratio of 5:2. The amino base II is diethylaminopropylamine.

[0043] The organic acid I is a combination of malonic acid and malic acid, with a weight ratio of 5:3. The organic acid II is malonic acid.

[0044] The alcohol additive is ethylene glycol.

[0045] The electrochemical inhibitor I is a combination of 3-aminotriazole and 5-aminotetrazolyl, with a weight ratio of 0.1:0.1. The electrochemical inhibitor II is 3-aminotriazole.

[0046] The stabilizers I and II are both phenylurea, and the solvent is water.

[0047] A method for preparing a copper-molybdenum metal etching solution composition comprises the following steps:

[0048] (1) Mix the main agent raw materials uniformly according to weight percentage;

[0049] (2) mixing the auxiliary raw materials uniformly according to weight percentage;

[0050] (3) Add the auxiliary agent to the main agent and mix them evenly for etching reaction.

[0051] Example 2

[0052] A copper-molybdenum metal etching liquid composition, the specific steps are the same as those in Example 1, the difference is that the preparation raw materials include, by weight percentage: a main agent is 8% hydrogen peroxide, an organic acid I is 6%, an amino base I is 8%, a stabilizer I is 0.1%, an electrochemical inhibitor I is 0.1%, an alcohol additive is 6%, and a solvent is used to supplement the balance.

[0053] The weight ratio of isobutanolamine to triethanolamine is 3:5; the weight ratio of malonic acid to malic acid is 5:1; and the weight ratio of 3-aminotriazole to 5-aminotetrazolyl is 0.05:0.05.

[0054] Example 3

[0055] A copper-molybdenum metal etching liquid composition, the specific steps are the same as those in Example 1, the difference is that the preparation raw materials include, by weight percentage: a main agent is 8% hydrogen peroxide, an organic acid I is 8%, an amino base I is 6%, a stabilizer I is 0.1%, an electrochemical inhibitor I is 0.3%, an alcohol additive is 8%, and a solvent is used to supplement the balance.

[0056] The weight ratio of isobutanolamine to triethanolamine is 3:3; the weight ratio of malonic acid to malic acid is 6:2; and the weight ratio of 3-aminotriazole to 5-aminotetrazolyl is 0.15:0.15.

[0057] Comparative Example 1

[0058] A copper-molybdenum metal etching liquid composition, the specific steps are the same as those of Example 1, but the difference is that it does not contain alcohol additives.

[0059] Comparative Example 2

[0060] A copper-molybdenum metal etching liquid composition, the specific steps are the same as those of Example 1, the difference is that the preparation raw materials include, by weight percentage: a main agent is 8% hydrogen peroxide, 6% organic acid I, 8% amino base I, 0.1% stabilizer I, 0.2% electrochemical inhibitor I, and a solvent to supplement the balance.

[0061] The weight ratio of isobutanolamine to triethanolamine is 3:5; the weight ratio of malonic acid to malic acid is 5:1.

[0062] Comparative Example 3

[0063] A copper-molybdenum metal etching liquid composition, the specific steps are the same as those of Example 1, the difference is that the preparation raw materials include, by weight percentage: a main agent is 8% hydrogen peroxide, an organic acid I is 6%, an amino base I is 6%, a stabilizer I is 0.1%, an electrochemical inhibitor I is 0.11%, and a solvent is used to supplement the balance.

[0064] The organic acid I is malonic acid, and the weight ratio of isobutanolamine to triethanolamine is 3:3.

[0065] Performance Testing

[0066] A copper-molybdenum film layer with a copper mold thickness of 5500 μm and a molybdenum film thickness of 300 μm was placed in the etching solution of Examples 1-3 and Comparative Examples 1-3 for etching reaction, and the etching temperature was 32° C. When used, for every increase of 1000 ppm of copper ions in the etching solution, 1.05% of the weight of the main agent was added to the system.

[0067] The test results are shown in Table 1.

[0068] Table 1

[0069]

Claims

1. A copper-molybdenum metal etching liquid composition, characterized in that, The preparation raw materials include a main agent and an auxiliary agent, which include, by weight percentage, 3-15% of hydrogen peroxide as the main agent, 1-15% of organic acid I, 1-15% of amino base I, 0.01-1% of stabilizer I, 0.01-1% of electrochemical inhibitor I, 1-10% of alcohol additives, and the balance is supplemented by solvent; the auxiliary agent includes 10-40% of organic acid II, 10-40% of amino base II, 0.01-2% of stabilizer II, 0.01-1% of electrochemical inhibitor II, and the balance is supplemented by solvent; The amount of the main agent and auxiliary agent added is 1%-1.5% of the main agent weight for every 1000ppm increase in copper ions; The amino base I is a combination of isobutanolamine and triethanolamine in a weight ratio of 5:2; The amino base II is diethylaminopropylamine; The organic acid I is a combination of malonic acid and malic acid in a weight ratio of 5:3; The organic acid II is malonic acid.

2. The copper-molybdenum metal etching liquid composition according to claim 1, characterized in that: The alcohol additive is a polyol, and the polyol is selected from one or a combination of ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, hexanediol, neopentyl glycol, and dipropylene glycol.

3. The copper-molybdenum metal etching liquid composition according to claim 2, characterized in that: The electrochemical inhibitors I and II are both azole compounds, selected from 3-aminotriazole, 5-aminotetrazolyl, or a combination of the two.

4. The copper-molybdenum metal etching liquid composition according to claim 3, characterized in that: The stabilizers I and II are both selected from one of phenylurea, p-hydroxybenzenesulfonic acid, ethanol, propanol or a combination of the two.

5. A method for preparing the copper-molybdenum metal etching liquid composition according to claim 4, characterized in that: The following steps are involved: (1) Mix the main agent raw materials uniformly according to weight percentage; (2) mixing the auxiliary raw materials uniformly according to weight percentage; (3) Add the auxiliary agent to the main agent and mix them evenly for etching reaction.

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