Efficient and low-corrosion alkaline cleaning solution

Abstract

The invention relates to the technical field of cleaning solutions, in particular to an efficient and low-corrosion alkaline cleaning solution which comprises the following components in percentage by weight: 70-85% of a component a and water; a component b: 5-10% of alcohol amine; 5-8% of a component c: quaternary ammonium base; a component d: 1-5% of organic acid; the pH value of the composition is 11-12. The cleaning composition has the core advantages that an alkaline cleaning system based on an organic amine-organic acid synergistic complexing effect is constructed, the system provides a strong alkaline environment through tris (2-ethoxyl) methyl ammonium hydroxide to efficiently dissolve copper oxide, and a stable mixed ligand complex is formed by means of organic alkali and organic acid; and efficient chelation and suspension of copper ions are realized, so that surface pollutants are removed, excellent surface cleanliness is obtained, and meanwhile, low-corrosion protection of a copper matrix is realized by virtue of an inherent alkaline environment and a dynamic adsorption effect of a system.

Description

Technical Field

[0001] This invention relates to the field of cleaning fluid technology, and in particular to a highly efficient, low-corrosion alkaline cleaning fluid. Background Technology

[0002] Planarization technology has become an indispensable and interdependent key technology in IC manufacturing processes, on par with photolithography and etching. Chemical mechanical polishing (CMP) and subsequent cleaning processes achieve wafer surface planarization through the coupling of chemical and mechanical actions, resulting in a surface with high flatness, low surface defects, and low residue. The polishing slurry and cleaning solution are crucial for ensuring process reliability and stability. Copper is the wiring metal for ICs at 65nm and below. To meet the requirements of copper CMP processes, introducing effective inhibitors into the polishing slurry and optimizing the cleaning solution composition are two pressing challenges in the CMP field.

[0003] During CMP (Chemical Metallurgy Process), the water-soluble corrosion inhibitor BTA forms a dense, insoluble protective film through physical / chemical adsorption. This film covers the copper surface, preventing contact between the copper and the external polishing solution, thus achieving corrosion inhibition. While BTA effectively protects the copper surface during CMP, the Cu-BTA complex formed between BTA and copper is prone to volatilization under high-temperature conditions, creating porosity and leading to corrosion degradation of the copper. + BTA molecules diffuse into the dielectric layer, leading to severe time-varying dielectric breakdown (TDDB) problems. Furthermore, residual BTA molecules cause issues such as high hydrophobicity on the copper surface, difficulty in drying, and poor adhesion of the stacking layers. When the particle size exceeds half the feature size, it can cause fatal defects such as short circuits or open circuits, unclear patterns, and dimensional variations. Therefore, cleaning residual BTA and its complexes is crucial in integrated circuit manufacturing.

[0004] The chemical properties of the cleaning solution and the acid / alkalinity of the environment significantly affect the formation and adsorption of the BTA film. It is generally believed that Cu-BTA is stable within a pH range of 4-10. In other words, a cleaning agent that can effectively remove BTA should have a pH less than 4 or greater than 10. However, strong acidic solutions may cause corrosion of copper and equipment surfaces, so alkaline cleaning solutions are becoming increasingly popular. Summary of the Invention

[0005] The purpose of this invention is to provide a highly efficient and low-corrosion alkaline cleaning solution to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a highly efficient, low-corrosion alkaline cleaning solution, comprising, by weight percentage: Ingredient a: 70-85%, water; Ingredient b: 5-10%, alkanolamine; Component c: 5-8%, quaternary ammonium base; Ingredient d: 1-5%, organic acids; The composition has a pH value of 11-12.

[0007] Preferably, component b is at least one compound selected from dimethylethanolamine, methyldiethanolamine, monoethanolamine, diethanolamine, triethanolamine, 2-amino-2-methyl-1-propanol, and aminoethylethanolamine.

[0008] Preferably, component c is selected from tris(2-hydroxyethyl)methylammonium hydroxide.

[0009] Preferably, component d is at least one compound selected from tartaric acid, ethanolamine, citric acid, oxalic acid, gluconic acid, ethylenediaminetetraacetic acid, formic acid, lactic acid, malic acid, phthalic acid, salicylic acid, catechol, resorcinol, and hydroquinone.

[0010] Compared with the prior art, the beneficial effects of the present invention are: The core advantage of the cleaning composition described in this invention lies in its construction of an alkaline cleaning system based on the synergistic complexation of organic amines and organic acids. This system provides a strongly alkaline environment through tris(2-hydroxyethyl)methylammonium hydroxide to efficiently dissolve copper oxides, and achieves efficient chelation and suspension of copper ions by forming stable mixed ligand complexes with organic bases and organic acids. Thus, while removing surface contaminants and obtaining excellent surface cleanliness, it also achieves low-corrosion protection of the copper substrate by virtue of the inherent alkaline environment and dynamic adsorption effect of the system. Attached Figure Description

[0011] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0012] Figure 1 This is the ingredient list for the alkaline cleaning solution of the present invention. Detailed Implementation

[0013] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] Please see Figure 1 The present invention provides a technical solution: A highly efficient, low-corrosion alkaline cleaning solution, comprising, by weight percentage: Ingredient a: 70-85%, water; Ingredient b: 5-10%, alkanolamine; Component c: 5-8%, quaternary ammonium base; Ingredient d: 1-5%, organic acids; The composition has a pH value of 11-12.

[0015] Specifically, component b is at least one compound selected from dimethylethanolamine, methyldiethanolamine, monoethanolamine, diethanolamine, triethanolamine, 2-amino-2-methyl-1-propanol, and aminoethylethanolamine.

[0016] Specifically, component c is selected from tris(2-hydroxyethyl)methylammonium hydroxide.

[0017] Specifically, component d is at least one compound selected from tartaric acid, ethanolamine, citric acid, oxalic acid, gluconic acid, ethylenediaminetetraacetic acid, formic acid, lactic acid, malic acid, phthalic acid, salicylic acid, catechol, resorcinol, and hydroquinone.

[0018] Example: Determination of Cu etching rate Cut the Cu sheet into pieces approximately 2.25cm in size. 2 Sample pieces were obtained. 1g of the cleaning solution (as shown in Table 1 for each example) and 100ml of pure water were added to a 250ml beaker. The beaker was placed at room temperature, and three parallel experiments were performed. The average corrosion rate of Cu was then calculated for each experiment. Table 1 summarizes the results of each example.

[0019]

[0020] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A highly efficient, low-corrosion alkaline cleaning solution, characterized in that, Includes, by weight percentage: Ingredient a: 70-85%, water; Ingredient b: 5-10%, alkanolamine; Component c: 5-8%, quaternary ammonium base; Ingredient d: 1-5%, organic acids; The pH value of the composition is 11-12.

2. The high-efficiency, low-corrosion alkaline cleaning solution according to claim 1, characterized in that, Component b is at least one compound selected from dimethylethanolamine, methyldiethanolamine, monoethanolamine, diethanolamine, triethanolamine, 2-amino-2-methyl-1-propanol, and aminoethylethanolamine.

3. The high-efficiency, low-corrosion alkaline cleaning solution according to claim 1, characterized in that, The component c is selected from tris(2-hydroxyethyl)methylammonium hydroxide.

4. The high-efficiency, low-corrosion alkaline cleaning solution according to claim 1, characterized in that, The component d is at least one compound selected from tartaric acid, ethanolamine, citric acid, oxalic acid, gluconic acid, ethylenediaminetetraacetic acid, formic acid, lactic acid, malic acid, phthalic acid, salicylic acid, catechol, resorcinol, and hydroquinone.

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