Cu-Mo alloy multi-film structure etching solution composition

Abstract

The invention relates to the technical field of etching solutions, in particular to the field of IPC C23F1, and more particularly relates to a Cu-Mo alloy multi-film structure etching solution composition. The etching solution comprises the following components in percentage by weight: 14-25% of hydrogen peroxide, 1-6% of a chelating agent, 0.5-4% of an etching agent, 0.1-3% of a regulator, 0.01-1% of an inhibitor, 0.02-6% of a stabilizer and the balance of water. The excellent etching performance conditions are as follows: CD-loss is 0.4-0.55 [mu] m, Taper angle is 40-50 DEG C, no residue and no crack exist, IGZO damagge # imgabs 0 # is below, the highest copper load is 3000 ppm or above, and the service time is 12 hr or above.

Description

Technical Field

[0001] The invention relates to the technical field of etching liquids, in particular to the field of IPC C23F1, and more specifically to a Cu-Mo alloy multi-film layer structure etching liquid composition. Background Art

[0002] In the current production process of liquid crystal panels, with the demand for large-size, high-resolution and driving frequency of liquid crystal display terminals such as televisions, higher requirements are placed on etching solutions. In traditional pH 2-3 etching solution compositions, hydrogen peroxide is generally used as the main oxidant, and inhibitors, chelating agents and fluorine compounds are also included. However, it is not suitable for etching substrates whose lower layer is an oxide semiconductor IGZO (In-Ga-Zn-O) and multilayer structures involving copper and molybdenum alloys. In order to improve the applicability of the lower film as a semiconductor oxide, a liquid composition with no fluorine added and a pH of more than 4 is sometimes used. However, due to the high pH value, there is a problem of short service life, low copper concentration life, and increased panel manufacturing costs.

[0003] Chinese invention patent CN115821264A discloses an etching solution composition, which includes hydrogen peroxide, corrosion inhibitor, etchant, residue remover, and fluorine compound. The etching solution composition provided by the present application can simultaneously etch a multilayer metal film stacked with a metal film and an oxide semiconductor film, reduce the number of etching times, and has no precipitates, which can effectively reduce production costs and improve process yield, but its critical dimension loss (CD-loss) is still as high as 0.9μm. Summary of the invention

[0004] The invention provides a Cu-Mo alloy multi-film layer structure etching liquid composition, which comprises, by weight percentage, 14-25% of hydrogen peroxide, 1-6% of a chelating agent, 0.5-4% of an etching agent, 0.1-3% of a regulating agent, 0.01-1% of an inhibitor, 0.02-6% of a stabilizer, and the balance is made up of water.

[0005] Preferably, the components include, by weight percentage: 16-23% hydrogen peroxide, 3-5% chelating agent, 1-3% etching agent, 0.5-2% regulator, 0.05-0.5% inhibitor, 0.5-3% stabilizer, and water makes up the balance.

[0006] The chelating agent includes at least one of nitrilotriethyl, ethylenediaminetetraacetic acid, diethyl trinitrovaleric acid, aminotrimethylenephosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, ethylenediaminetetramethylenephosphonic acid, diethylenetriaminepenta(methylenephosphonic acid), alanine, glutamic acid, aminobutyric acid, and glycine.

[0007] The etchant includes an organic acid not containing a nitrogen atom and / or a salt of an organic acid not containing a nitrogen atom.

[0008] The non-nitrogen-containing organic acid includes at least one of acetic acid, formic acid, butyric acid, citric acid, glycolic acid, oxalic acid, malonic acid, malic acid, valeric acid, propionic acid, tartaric acid, gluconic acid, and succinic acid.

[0009] The regulator includes at least one of ascorbic acid, glycine, iminodiacetic acid, alanine, valine, glutamic acid, aspartic acid, glutamine, asparagine, serine, threonine, cysteine, cysteineamine, histidine, phenylalanine, lysine, and arginine.

[0010] The weight ratio of the etchant to the regulator is 2:(0.2-2).

[0011] Preferably, the weight ratio of the etchant to the regulator is 2:(1-2).

[0012] Further preferably, the weight ratio of the etchant to the regulator is 2:(1-1.2).

[0013] The etching solution prepared by the present application has an excellent etching effect on the film structure with MTD (molybdenum-titanium-nickel alloy) as the upper layer, Cu as the middle layer, and MoTi (molybdenum-titanium alloy) as the lower layer: the taper angle is 40-50°, no residue, and no cracks. The critical dimension loss (CD-loss) is less than 0.6μm. If the top layer is an MTD alloy film, the adhesion with the PR (photoresist) is weak, and the etching speed is very fast compared with the lower MoTi. In order to solve the problem of poor etching characteristics caused by upper erosion of the liquid, the present application further studied and found that the weight ratio of etchant and regulator is 2: (0.2-2) added to the formula, and the critical dimension loss (CD-loss) can be less than 0.6μm. The etchant is adsorbed between the MTD and Cu interfaces to form the required taper angle characteristics. At the same time, in order to form a specific critical dimension loss, the three layers of the film need to be over-etched, and a large dimension loss will also be formed. By using Cl in a specific regulator, - The strong negative ions are adsorbed on the inner side of PR, resulting in a smaller size loss.

[0014] The present application has found that the stabilizer includes a first stabilizer and a second stabilizer, the first stabilizer includes an alkylamine compound, the second stabilizer includes a nitride and / or an N-oxide, and the weight ratio of the first stabilizer to the second stabilizer is (0.0.1-3): (0.0.1-3), which can minimize the damage to IGZO when the lower film is a semiconductor oxide. In the absence of fluoride, the pH concentration must be increased, but if the pH is increased, when metal ions accumulate, hydrogen peroxide will be attacked by metal ions and decompose. After hydrogen peroxide decomposes, free radicals are generated, which attack the organic matter added to the etching solution composition, and a free radical reaction occurs in which the composition decomposes as a whole. The present application selects specific stabilizers, wherein the first stabilizer can reduce the free radicals generated, slow down the free radical reaction, and thus increase the use time; the second stabilizer can slow down the free radical cycle, thereby increasing the service life, and achieving the effect of reducing the display manufacturing cost compared with the past.

[0015] The inhibitor includes at least one of NaCl, KCl, NH4Cl, malonyl chloride and choline chloride.

[0016] Preferably, the amount of the inhibitor added to the etching solution composition is 0.05-0.2 wt %.

[0017] More preferably, the amount of the inhibitor added to the etching solution composition is 0.05-0.1 wt %.

[0018] The stabilizer includes a first stabilizer and a second stabilizer, wherein the first stabilizer includes an alkylamine compound, and the second stabilizer includes a nitride and / or an N-oxide.

[0019] Preferably, the alkylamine compound includes at least one of butylamine, pentylamine, octylamine, 2-ethyl-1-butylamine, 2-hexylamine, 2-ethyl-hexylamine, heptylamine and cyclohexylamine.

[0020] Preferably, the nitride includes at least one of isoquinoline, indole, imidazole, 1-methylimidazole, and diisopropylamine.

[0021] Preferably, the N-oxide includes at least one of N-methylmorpholine-N-oxide, trimethylamine-N-oxide, triethylamine-N-oxide, pyridine-N-oxide, N-ethylmorpholine-N-oxide, N-methylpyrrolidine-N-oxide and N-ethylpyrrolidine-N-oxide.

[0022] The weight ratio of the first stabilizer to the second stabilizer is (0.0.1-3): (0.0.1-3).

[0023] Preferably, the weight ratio of the first stabilizer to the second stabilizer is (0.2-1):(0.2-2).

[0024] More preferably, the weight ratio of the first stabilizer to the second stabilizer is (0.5-1):(0.2-1).

[0025] More preferably, the weight ratio of the first stabilizer to the second stabilizer is (0.5-0.7):1.

[0026] Beneficial Effects

[0027] 1. The etching solution prepared in the present application avoids the addition of fluoride and exhibits excellent etching performance on copper and molybdenum alloy multilayer film structures.

[0028] 2. The etching solution prepared in this application is effective for the film with MTD as the upper layer, Cu as the middle layer and MoTi as the lower layer.

[0029] The structure has excellent etching effect: taper angle 40-50°, no residue, no cracks.

[0030] 3. The stabilizer includes a first stabilizer and a second stabilizer, the first stabilizer includes an alkylamine compound, the second stabilizer includes a nitride and / or an N-oxide, and the weight ratio of the first stabilizer to the second stabilizer is (0.0.1-3): (0.0.1-3), which can minimize the damage to IGZO when the underlying film is a semiconductor oxide.

[0031] 4. The formula adds etchant and conditioner in a weight ratio of 2: (0.2-2), critical dimension loss (CD-loss)

[0032] Can be lower than 0.6μm.

[0033] 5. The etching solution prepared in this application has a maximum copper load of more than 3000 ppm and can be used for more than 12 hours. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is the etching electron microscope image of Example 1 on the etching substrate MTD / Cu / MoTi.

[0035] Figure 2 This is the etching electron microscope image of comparative example 1 on the etching substrate MTD / Cu / MoTi.

[0036] Figure 3 This is the etching electron microscope image of comparative example 2 on the etching substrate MTD / Cu / MoTi.

[0037] Figure 4 This is the etching electron microscope image of comparative example 3 on the etching substrate MTD / Cu / MoTi. DETAILED DESCRIPTION

[0038] Examples 1-4, Comparative Examples 1-3

[0039] A Cu-Mo alloy multi-layer structure etching solution composition, the components by weight percentage are shown in Table 1:

[0040] Table 1

[0041]

[0042] Preparation of the etching solution composition: all components are mixed evenly to obtain the etching solution.

[0043] Performance testing methods and data

[0044] The etching performance of the embodiment and the comparative example was tested, and the etching conditions were: the upper layer was MTD, the thickness The middle layer is Cu, with a thickness of The lower layer is MoTi, with a thickness of Etching temperature (32°C), etching time (110s). The test data are listed in Table 1.

[0045] The etching solutions prepared in Example 1 and Comparative Examples 1-3 were used for etching, and the substrates after etching were tested by electron microscopy.

[0046] Performance test data

[0047] Table 1

[0048]

[0049]

[0050] like Figure 1-4 As shown, Figure 1 Shows excellent etching effect; Figure 2 CD-loss is as high as 1.67μm and cone angle is only 19.8°; Figure 3 CD-loss is as high as 1.28μm and cone angle is only 35.1°; Figure 4 The cone angle is only 24.1°, which is visible Figure 2-4 All of them showed poor etching.

Claims

1. A Cu-Mo alloy multi-layer structure etching solution composition, characterized in that: Calculated by weight percentage, the components include: 14-25% hydrogen peroxide, 1-6% chelating agent, 0.5-4% etching agent, 0.1-3% regulating agent, 0.01-1% inhibitor, 0.02-6% stabilizer, and water makes up the balance.

2. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 1, characterized in that: Calculated by weight percentage, the components include: 16-23% hydrogen peroxide, 3-5% chelating agent, 1-3% etching agent, 0.5-2% regulator, 0.05-0.5% inhibitor, 0.5-3% stabilizer, and water makes up the balance.

3. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 2, characterized in that: The chelating agent includes at least one of nitrilotriethyl, ethylenediaminetetraacetic acid, diethyl trinitrovaleric acid, aminotrimethylenephosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, ethylenediaminetetramethylenephosphonic acid, diethylenetriaminepenta(methylenephosphonic acid), alanine, glutamic acid, aminobutyric acid, and glycine.

4. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 3, characterized in that: The etchant includes an organic acid not containing a nitrogen atom and / or a salt of an organic acid not containing a nitrogen atom.

5. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 4, characterized in that: The non-nitrogen-containing organic acid includes at least one of acetic acid, formic acid, butyric acid, citric acid, glycolic acid, oxalic acid, malonic acid, malic acid, valeric acid, propionic acid, tartaric acid, gluconic acid, and succinic acid.

6. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 5, characterized in that: The regulator includes at least one of ascorbic acid, glycine, iminodiacetic acid, alanine, valine, glutamic acid, aspartic acid, glutamine, asparagine, serine, threonine, cysteine, cysteineamine, histidine, phenylalanine, lysine, and arginine.

7. The Cu-Mo alloy multi-layer structure etching liquid composition according to claim 1 or 6, characterized in that: The weight ratio of the etchant to the regulator is 2:(0.2-2).

8. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 7, characterized in that: The inhibitor includes at least one of NaCl, KCl, NH4Cl, malonyl chloride and choline chloride.

9. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 8, characterized in that: The stabilizer includes a first stabilizer and a second stabilizer, wherein the first stabilizer includes an alkylamine compound, and the second stabilizer includes a nitride and / or an N-oxide.

10. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 9, characterized in that: The weight ratio of the first stabilizer to the second stabilizer is (0.0.1-3): (0.0.1-3).

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