Double-agent copper-molybdenum-titanium etching solution and preparation method thereof

Abstract

The invention relates to the technical field of etching solutions, in particular to the field of IPC C23F, and more particularly relates to a double-agent copper-molybdenum-titanium etching solution and a preparation method thereof. Comprising a main agent and an auxiliary agent, and the main agent comprises the following components in parts by weight: 8-15 parts of an oxidizing agent, 4-13 parts of first organic acid, 1-3 parts of first inorganic acid, 1-3 parts of first organic alkali, 1-4 parts of a first surfactant, 0.05-0.5 part of a first fluorine-containing compound, 0.01-1 part of a first corrosion inhibitor and 60-80 parts of water; and the auxiliary agent comprises the following components: 10-60 parts of second organic acid, 2-10 parts of second inorganic acid, 1-5 parts of second organic alkali, 0.05-0.5 part of a second fluorine-containing compound, 1-5 parts of a second surfactant, 0.5-2 parts of a second corrosion inhibitor and 50-80 parts of water. The problems of large etching rate fluctuation, chamfering, vertical angle, precipitation, crystallization and the like in the etching process of the etching liquid are solved.

Description

Technical Field

[0001] The invention relates to the technical field of etching liquids, in particular to the field of IPC C23F, and more specifically to a dual-type copper-molybdenum-titanium etching liquid and a preparation method thereof. Background Art

[0002] With the development of display technology, especially the development of display technology towards large-scale and high-resolution, traditional metal wires will amplify signal delays and other problems as the wiring becomes longer and the resistance increases, causing the display effect to deteriorate. Therefore, the research and development of metal wiring with lower resistance, that is, the research and development of copper processes, began. Due to the different compositions of metal film layers, the ratio of each film layer is different, so the etching solution is a special chemical. The main acids in existing etchants are mostly citric acid, nitric acid, phosphoric acid, hydroxyethyl sulfonic acid, iminodiacetic acid, etc. The single use of these raw materials will result in poor etching problems.

[0003] CN109136931A discloses a high-efficiency copper-molybdenum etching solution, comprising: the main components of the etching solution include 7-15% hydrogen peroxide accounting for the total mass percentage of the etching solution, 2-7% of the total mass percentage of the etching solution, 1-3% of the total mass percentage of the etching solution, an organic acid accounting for 3-10% of the total mass percentage of the etching solution, 0.001-1% of the total mass percentage of the etching solution, and a pH regulator accounting for 1-10% of the total mass percentage of the etching solution, and the balance is deionized water; the invention enhances the oxidation ability of the copper-molybdenum metal film layer, further accelerates the etching reaction rate, and further improves the etching quality, but a single type of organic acid cannot simultaneously solve the problems of large fluctuations in etching rate, chamfering, vertical angles, precipitation and crystallization. Summary of the invention

[0004] The first aspect of the present invention provides a dual-type copper-molybdenum-titanium etching solution, comprising a main agent and an auxiliary agent, wherein the components of the main agent include, by weight: 8-15 parts of an oxidant, 4-13 parts of a first organic acid, 1-3 parts of a first inorganic acid, 1-3 parts of a first organic base, 1-4 parts of a first surfactant, 0.05-0.5 parts of a first fluorine-containing compound, 0.01-1 parts of a first corrosion inhibitor, and 60-80 parts of water; the components of the auxiliary agent include: 10-60 parts of a second organic acid, 2-10 parts of a second inorganic acid, 1-5 parts of a second organic base, 0.05-0.5 parts of a second fluorine-containing compound, 1-5 parts of a second surfactant, 0.5-2 parts of a second corrosion inhibitor, and 50-80 parts of water.

[0005] The oxidant includes one of hydrogen peroxide and persulfate.

[0006] The first organic acid and the second organic acid are both selected from at least one of citric acid, iminodiacetic acid, glycolic acid, lactic acid, isethionic acid, and phenolsulfonic acid.

[0007] The first surfactant and the second surfactant are both selected from at least one of ethylene glycol, glycerol, mercaptan, ethylene glycol butyl ether, glycerol ethyl ether, and glycerol methyl ether.

[0008] Preferably, the first organic acid and the second organic acid are both selected from at least one of lactic acid, citric acid and isethionic acid.

[0009] The first inorganic acid and the second inorganic acid are both selected from at least one of hydrochloric acid, nitric acid, phosphoric acid, and pyrophosphoric acid.

[0010] The first organic base and the second organic base are both selected from at least one of phenylenediamine, dimethylaminopropylamine, isopropanolamine, diethanolamine, and triisopropanolamine.

[0011] The first corrosion inhibitor and the second corrosion inhibitor are both selected from at least one of methyl nitrogen azoles, amino nitrogen azoles, and pantothenic acid.

[0012] The first fluorine-containing compound and the second fluorine-containing compound are both selected from at least one of hydrofluoric acid, ammonium fluoride, and ammonium bifluoride.

[0013] Preferably, the first corrosion inhibitor and the second corrosion inhibitor are both selected from at least one of pyridine-3-carboxylic acid, 5-aminotetrazolyl, 5-methyltetrazolyl, 4-amino-1,2,4-triazole, and 3-amino-1,2,4-triazole.

[0014] Further preferably, the first corrosion inhibitor and the second corrosion inhibitor both include pyridine-3-carboxylic acid and 4-amino-1,2,4-triazole.

[0015] Further preferably, the weight ratio of pyridine-3-carboxylic acid to 4-amino-1,2,4-triazole in the main agent is (2-5):1.

[0016] The weight ratio of the oxidant to the first fluorine-containing compound is (8-15):0.1.

[0017] Preferably, the weight ratio of the oxidant to the first fluorine-containing compound is (8-11):0.1.

[0018] Preferably, the main agent includes lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid, and the weight ratio of lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid is 12: (0.05-0.3): (1-5): (0.1-1).

[0019] Preferably, the main agent includes glycerol methyl ether and dimethylethanolamine, and the weight ratio of glycerol methyl ether to dimethylethanolamine is 1:(2-5).

[0020] Preferably, the main agent includes lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid, and the weight ratio of lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid is 12: (0.05-0.2): (2-4): (0.1-0.6).

[0021] The present application has found that by adding a fluorine compound to the main agent, and the weight ratio of the oxidant to the first fluorine-containing compound is (8-11):0.1, the etching rate can be slowed down so that CD-loss is less than 0.9μm. However, when the fluorine-containing etching solution is applied to titanium metal, most of the time, precipitates or crystals will appear. In particular, after 6000ppm, the precipitates and precipitates increase significantly, which will clog the filter element and prevent mass production. The present application has further found that the main agent includes lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid, and the weight ratio of lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid is 12:(0.05-0.2):(2-4):(0.1-0.6), which can solve the problems of large fluctuations in etching rate, chamfers, vertical angles, precipitation and crystallization, and obtain excellent etching morphology.

[0022] Further preferably, the main agent includes glycerol methyl ether and dimethylethanolamine, and the weight ratio of glycerol methyl ether to dimethylethanolamine is 1:(2-4).

[0023] Preferably, the amount of the second organic acid added to the auxiliary agent is 45-50 wt %.

[0024] The weight ratio of the second organic acid to the second inorganic acid is 50:(1-5).

[0025] Preferably, the weight ratio of the second organic acid to the second inorganic acid is 50:(1-3).

[0026] The weight ratio of the second organic base, the second fluorine-containing compound, the second surfactant and the second corrosion inhibitor is 5:(0.2-1):(1-4):(1-3).

[0027] Preferably, the auxiliary agent includes the following components: lactic acid, hydrofluoric acid, nitric acid, pyridine-3-carboxylic acid, glycerol methyl ether and dimethylethanolamine.

[0028] The second aspect of the present invention provides a method for preparing a dual-type copper-molybdenum-titanium etching solution, comprising the following steps: mixing the components of the main agent evenly, and mixing the components of the auxiliary agent evenly, to obtain.

[0029] Beneficial Effects

[0030] 1. By adding a fluorine compound to the main agent, the weight ratio of the oxidant to the first fluorine-containing compound is (8-11):

[0031] 0.1, can slow down the etching rate, making CD-loss < 0.9μm.

[0032] 2. The main agent includes lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid, and the weight ratio of lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid is 12: (0.05-0.2): (2-4): (0.1-0.6), which can solve the problems of large fluctuation of etching rate, chamfering, vertical angle, precipitation and crystallization.

[0033] 3. The life of the dual-type etching solution of this application can reach 14000ppm, which greatly reduces the probability of scratching the crystallized glass substrate.

[0034] 4. The initial concentration of the oxidant is moderate (8%-14%) and the safety risk is low.

[0035] 5. The dual-type etching solution of the present application does not cause problems such as chamfering and metal interface cracks during the etching process.

[0036] 6. The dual-type etching solution of this application has molybdenum-titanium tailing during etching (molybdenum residue lower limit <0.6μm, tailing 0.10-0.2μm), the morphology is good, there is no precipitation at the end of the etching solution, and the etching characteristics are stable (slope angle

[0037] 60-70°). BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It shows: the copper, molybdenum and titanium morphology after etching in Example 5.

[0039] Figure 2 yes Figure 1 According to the SEM measurement results, CD-loss = 0.75-0.85um Taper = 60-70° is the best.

[0040] Figure 3 It shows that the lower limit of the molybdenum and titanium residue after etching in Example 5 is the best when CD-loss is less than 0.6 um.

[0041] Figure 4 It shows: the tailing morphology after etching of Example 5. 0.1um<tailing CD-loss<0.2um is the best. DETAILED DESCRIPTION

[0042] Examples 1-8

[0043] A dual-agent copper-molybdenum-titanium etching solution comprises a main agent and an auxiliary agent, and the formula is shown in Table 1 in parts by weight:

[0044] Table 1

[0045]

[0046]

[0047] A preparation method of a dual-agent copper-molybdenum-titanium etching solution comprises the following steps: mixing components of a main agent evenly, and mixing components of an auxiliary agent evenly to obtain the dual-agent copper-molybdenum-titanium etching solution.

[0048] Performance testing methods and data

[0049] The specific method of using the etching composition for etching is as follows: first use the main etching agent, and for every 1000 ppm increase in copper ions, add 1 wt% of the main agent dosage of the auxiliary agent to the system. The etching test results are shown in Table 2.

[0050] Figure 1 It shows: the copper, molybdenum and titanium morphology after etching in Example 5.

[0051] Figure 2 yes Figure 1 The measurement SEM results show that CD-loss = 0.75-0.85μm and Taper = 60-70° are the best.

[0052] Figure 3 It shows that the lower limit of the molybdenum and titanium residue after etching in Example 5 is the best when CD-loss is less than 0.6 um.

[0053] Figure 4 It shows: the tailing morphology after etching of Example 5. 0.1um<tailing CD-loss<0.2um is the best.

[0054] Table 2

[0055]

Claims

1. A dual-type copper-molybdenum-titanium etching solution, characterized in that: The invention comprises a main agent and an auxiliary agent. The components of the main agent include, by weight, 8-15 parts of an oxidant, 4-13 parts of a first organic acid, 1-3 parts of a first inorganic acid, 1-3 parts of a first organic base, 1-4 parts of a first surfactant, 0.05-0.5 parts of a first fluorine-containing compound, 0.01-1 parts of a first corrosion inhibitor, and 60-80 parts of water; the components of the auxiliary agent include, by weight, 10-60 parts of a second organic acid, 2-10 parts of a second inorganic acid, 1-5 parts of a second organic base, 0.05-0.5 parts of a second fluorine-containing compound, 1-5 parts of a second surfactant, 0.5-2 parts of a second corrosion inhibitor, and 50-80 parts of water.

2. The double-component copper-molybdenum-titanium etching solution according to claim 1, characterized in that: The oxidant includes one of hydrogen peroxide and persulfate.

3. The double-type copper-molybdenum-titanium etching solution according to claim 2, characterized in that: The first organic acid and the second organic acid are both selected from at least one of citric acid, iminodiacetic acid, glycolic acid, lactic acid, isethionic acid, and phenolsulfonic acid.

4. The double-type copper-molybdenum-titanium etching solution according to claim 3, characterized in that: The first inorganic acid and the second inorganic acid are both selected from at least one of hydrochloric acid, nitric acid, phosphoric acid, and pyrophosphoric acid.

5. The dual-type copper-molybdenum-titanium etching solution according to claim 4, characterized in that: The first organic base and the second organic base are both selected from at least one of phenylenediamine, dimethylaminopropylamine, isopropanolamine, diethanolamine, and triisopropanolamine.

6. The dual-type copper-molybdenum-titanium etching solution according to claim 5, characterized in that: The first corrosion inhibitor and the second corrosion inhibitor are both selected from at least one of methyl nitrogen azoles, amino nitrogen azoles, and pantothenic acid.

7. The dual-type copper-molybdenum-titanium etching solution according to claim 6, characterized in that: The first fluorine-containing compound and the second fluorine-containing compound are both selected from at least one of hydrofluoric acid, ammonium fluoride, and ammonium bifluoride.

8. The dual-type copper-molybdenum-titanium etching solution according to claim 7, characterized in that: The weight ratio of the oxidant to the first fluorine-containing compound is (8-15):0.

1.

9. The dual-type copper-molybdenum-titanium etching solution according to claim 8, characterized in that: The main agent includes lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid, and the weight ratio of the lactic acid, hydrofluoric acid, nitric acid and pyridine-3-carboxylic acid is 12: (0.05-0.3): (1-5): (0.1-1).

10. A method for preparing the dual-type copper-molybdenum-titanium etching solution according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: mixing components of the main agent evenly, and mixing components of the auxiliary agent evenly to obtain the product.

Images