Cu-Mo alloy multi-film structure etching solution composition

Abstract

The invention relates to an etching solution composition for a Cu-Mo alloy multi-film structure. The etching solution comprises the following components in percentage by weight: 13-25% of hydrogen peroxide, 1-5% of a chelating agent, 0.2-9% of an etching agent, 0.01-1.5% of an inhibitor, 0.005-1% of a fluorine compound, 0.005-0.5% of an interface protective agent, 0.01-3% of a hydrogen peroxide stabilizer and the balance of water, the interface protective agent comprises a compound containing a sulfonic acid group. The etching solution composition prepared by the invention can be adapted to a 2W1D (two-time wet etching and one-time dry etching) process, the panel manufacturing cost is reduced, and the yield is improved; the fluorine compound comprises hydrogen fluoride and sodium hydrogenfluoride in a weight ratio of (1-3): 1, the roughness of the a-Si surface can be reduced, CD-loss (unilateral loss) is 0.6-0.7 [mu] m, and the taper angle is 50-60 degrees.

Description

Technical Field

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

[0002] In the traditional semiconductor manufacturing process, especially in the Source / Drain wiring formation stage involving the 4mask process, it is achieved through 1st wet etching → 1st dry etching → 2nd wet etching → 2nd dry etching (2W2D). It is crucial to use specific chemical etching steps to accurately carve out the circuit pattern. In this process, hydrogen peroxide plays a key role as the main oxidant in an acidic environment with a pH value of 2 to 3. It promotes chemical reactions on the surface of the material through oxidation, thereby achieving an etching effect. At present, attempts are being made to use the 2W1D (2 wet etching, 1 dry etching) process to achieve the purpose of reducing costs, but there is a large roughness on the a-Si surface, which leads to poor electrical components.

[0003] Chinese invention patent CN118085870A discloses an etching solution, an etching method and a method for preparing an array substrate, providing an etching solution, including 8-15 parts by weight of an oxidant, 0.0005-0.006 parts by weight of a fluoride, 3-6 parts by weight of a chelating agent, 2-5 parts by weight of an organic base, 2 parts by weight or less of an azole compound, 3 parts by weight or less of an anti-potential etchant, and 60-85 parts by weight of a solvent. The etching solution is used to wet etch the metal layer and the semiconductor layer in the array substrate once and dry etch once, thereby improving the etching tailing problem of the amorphous silicon layer and not involving the problem of the roughness of the a-Si surface. Summary of the invention

[0004] The invention provides a Cu-Mo alloy multi-film layer structure etching solution composition, which comprises, by weight percentage, 13-25% of hydrogen peroxide, 1-5% of a chelating agent, 0.2-9% of an etching agent, 0.01-1.5% of an inhibitor, 0.005-1% of a fluorine compound, 0.005-0.5% of an interface protective agent, 0.01-3% of a hydrogen peroxide stabilizer, and the balance being supplemented by water; the interface protective agent comprises a compound containing a sulfonic acid group.

[0005] Preferably, the components include, by weight percentage: 15-20% hydrogen peroxide, 1.5-3.5% chelating agent, 1-4.5% etchant, 0.1-0.8% inhibitor, 0.01-0.1% fluorine compound, 0.008-0.5% interface protective agent, 0.2-1% hydrogen peroxide stabilizer, and water makes up the balance.

[0006] The compound containing sulfonic acid group includes at least one of 2-ethylhexyl sulfonic acid, dodecylbenzene sulfonic acid, sodium xylene sulfonate, disodium 2,6-naphthalene disulfonate, sodium α-methylstyrene sulfonate, ethylbenzene sulfonate, polyacrylamide-2-methylpropane sulfonic acid, and sodium 4-vinylbenzene sulfonate.

[0007] The fluorine compound includes at least one of hydrogen fluoride, sodium fluoride, potassium fluoride, aluminum trifluoride, fluoroboric acid, ammonium fluoride, ammonium bifluoride, sodium bifluoride, and potassium metadihydrofluoride.

[0008] The fluorine compound includes hydrogen fluoride and sodium hydrogen fluoride, and the weight ratio of the hydrogen fluoride to the sodium hydrogen fluoride is (1-3):1.

[0009] Preferably, the weight ratio of hydrogen fluoride to sodium bifluoride is (7-8):4.

[0010] The etchant includes a first etchant and a second etchant, wherein the first etchant includes an organic acid not containing nitrogen atoms and / or a salt of an organic acid not containing nitrogen atoms, and the second etchant includes a sulfate and / or a persulfate.

[0011] The weight ratio of the first etchant to the second etchant is (0.5-2):(0.5-2.5).

[0012] Preferably, the weight ratio of the first etchant to the second etchant is 1:(1-2.5).

[0013] The applicant has found that the fluorine compound includes hydrogen fluoride and sodium bifluoride, and the weight ratio of hydrogen fluoride to sodium bifluoride is (1-3): 1. The roughness of the a-Si surface can be reduced, CD-loss (single-side loss) is 0.6-0.7μm, and the taper angle is 50-60°. It may be that in the 2nd wet etching process, the n+ layer containing doping in the a-Si is completely removed, reducing the damage to the a-Si layer exposed to the composition later. Therefore, the roughness of the surface of the a-Si layer in the channel part is small, which will also have a good effect on the characteristics of the element. Further research has found that adding a specific content of an interface protective agent containing a sulfonic acid group can further reduce the generation of Si-based precipitates during the etching process. It may be that the damage to the glass substrate and the gate insulating film by the sulfonic acid group-containing compound is minimized, even if the service life (number of processed pieces) in the composition is increased.

[0014] The first etchant 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.

[0015] The second etchant includes at least one of potassium bisulfate, sodium bisulfate, sodium sulfate, sodium persulfate, potassium persulfate, potassium sulfate, ammonium sulfate, and ammonium persulfate.

[0016] The hydrogen peroxide stabilizer includes alkylamine compounds.

[0017] Preferably, the hydrogen peroxide stabilizer includes at least one of butylamine, pentylamine, octylamine, 2-ethyl-1-butylamine, 2-hexylamine, 2-ethyl-hexylamine, 2-ethyl-hexylamine, heptylamine, hexylamine, and cyclohexylamine.

[0018] The chelating agent includes at least one of iminodiacetic acid, nitrilotriacetic acid, 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.

[0019] The inhibitors include heterocyclic aromatic compounds and / or heterocyclic aliphatic compounds.

[0020] Preferably, the heterocyclic aromatic compound includes at least one of furan, thiophene, pyrrole, oxazole, imidazole, pyrazole, triazole, tetrazole, 5-aminotetrazole, and methyltetrazole.

[0021] Preferably, the heterocyclic aliphatic compound includes at least one of piperazine, methylpiperazine, hydroxyethylpiperazine, pyrrolidine and alloxan.

[0022] Beneficial Effects

[0023] 1. The etching solution composition prepared in the present application can be adapted to the 2W1D (2 wet etchings, 1 dry etching) process, thereby reducing panel manufacturing costs and improving yields.

[0024] 2. The fluorine compound includes hydrogen fluoride and sodium hydrogen fluoride, and the weight ratio of hydrogen fluoride to sodium hydrogen fluoride is (1-3): 1. The roughness of the a-Si surface can be reduced, with a CD-loss (single-side loss) of 0.6 to 0.7 μm and a Taper angle of 50 to 60°.

[0025] 3. Adding a specific amount of an interface protective agent containing a sulfonic acid group can further reduce the generation of Si-based precipitates during the etching process.

[0026] 4. The etching solution composition prepared in this application can achieve a maximum copper loading of

[0027] 7000ppm.

[0028] 5. The etching solution composition prepared in the present application leaves no residue, no cracks, and no undercut when etching Cu-MoNb. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The etching electron microscope image of the etching solution composition prepared in Example 1.

[0030] Figure 2 This is an etching electron microscope image of the etching solution composition prepared in Comparative Example 1.

[0031] Figure 3 This is an etching electron microscope image of the etching solution composition prepared in Comparative Example 2.

[0032] Figure 4 This is an etching electron microscope image of the etching solution composition prepared in Comparative Example 3. DETAILED DESCRIPTION

[0033] Examples 1-4, Comparative Examples 1-3

[0034] A Cu-Mo alloy multi-layer structure etching solution composition, the components by weight percentage are shown in Table 1:

[0035] Table 1

[0036]

[0037] Preparation of the etching solution composition: all components are mixed evenly to obtain the etching solution.

[0038] Performance testing methods and data

[0039] The etching performance of the etching solutions prepared in the examples and comparative examples was tested, and the test data are listed in Table 2.

[0040] Etching performance evaluation: After etching is completed, the etching performance is confirmed using SEM analysis equipment.

[0041] Conditions for excellent etching performance: CD-loss (single-side loss) 0.6-0.7μm, Taper angle 50-60°, no residue, no cracks, no undercut.

[0042] Maximum copper loading (ppm): Starting from a copper concentration of 500 ppm, the CD bias (etch critical dimension bias) and Taper angle variation exceeds 10%, or the copper concentration time point where residual and undertcut are observed.

[0043] Evaluation of Si-based precipitate: 1000 ppm of Cu and 0.2 g of Si powder were completely dissolved in the composition. After 1 hour, the composition was left at room temperature for 3 days to check whether a precipitate was generated.

[0044] 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 microscope.

[0045] Table 2

[0046]

[0047]

[0048] like Figure 1-4 As shown, Figure 1 Shows excellent etching effect; Figure 2-4 All of them showed poor etching. Figure 2 There is an undercut, Figure 3 The cone angle is too small. Figure 4 There are Si-based precipitates.

Claims

1. A Cu-Mo alloy multi-layer structure etching solution composition, characterized in that: The components include, by weight percentage: 13-25% hydrogen peroxide, 1-5% chelating agent, 0.2-9% etching agent, 0.01-1.5% inhibitor, 0.005-1% fluorine compound, 0.005-0.5% interface protective agent, 0.01-3% hydrogen peroxide stabilizer, and water making up the balance; the interface protective agent includes a compound containing a sulfonic acid group.

2. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 1, characterized in that: The components include, by weight percentage: 15-20% hydrogen peroxide, 1.5-3.5% chelating agent, 1-4.5% etching agent, 0.1-0.8% inhibitor, 0.01-0.1% fluorine compound, 0.008-0.5% interface protective agent, 0.2-1% hydrogen peroxide stabilizer, and the balance is made up of water.

3. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 2, characterized in that: The compound containing sulfonic acid group includes at least one of 2-ethylhexyl sulfonic acid, dodecylbenzene sulfonic acid, sodium xylene sulfonate, disodium 2,6-naphthalene disulfonate, sodium α-methylstyrene sulfonate, ethylbenzene sulfonate, polyacrylamide-2-methylpropane sulfonic acid, and sodium 4-vinylbenzene sulfonate.

4. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 3, characterized in that: The fluorine compound includes at least one of hydrogen fluoride, sodium fluoride, potassium fluoride, aluminum trifluoride, fluoroboric acid, ammonium fluoride, ammonium bifluoride, sodium bifluoride, and potassium metadihydrofluoride.

5. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 4, characterized in that: The fluorine compound includes hydrogen fluoride and sodium hydrogen fluoride, and the weight ratio of the hydrogen fluoride to the sodium hydrogen fluoride is (1-3):

1.

6. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 1, characterized in that: The etchant includes a first etchant and a second etchant, wherein the first etchant includes an organic acid not containing nitrogen atoms and / or a salt of an organic acid not containing nitrogen atoms, and the second etchant includes a sulfate and / or a persulfate.

7. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 6, characterized in that: The weight ratio of the first etchant to the second etchant is (0.5-2):(0.5-2.5).

8. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 7, characterized in that: The first etchant 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.

9. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 8, characterized in that: The second etchant includes at least one of potassium bisulfate, sodium bisulfate, sodium sulfate, sodium persulfate, potassium persulfate, potassium sulfate, ammonium sulfate, and ammonium persulfate.

10. The Cu-Mo alloy multi-layer structure etching solution composition according to claim 9, characterized in that: The hydrogen peroxide stabilizer includes alkylamine compounds.

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