Corrosion inhibition enhanced chip cleaning agent as well as preparation method and application thereof

Abstract

The invention relates to a corrosion inhibition enhanced chip cleaning agent as well as a preparation method and application thereof, and the corrosion inhibition enhanced chip cleaning agent comprises the following components in parts by weight: 0.001-0.01 part of a pyranoside corrosion inhibitor; 0.1 to 0.5 part of a chelating agent; 0.1 to 2 parts of organic acid; 0.1 to 2 parts of fluoride; 60-90 parts of an organic solvent; and 20 to 50 parts of ultrapure water, wherein the pyranoside corrosion inhibitor is alkyl sulfo-pyranoside. The alkyl sulfo-pyranoside corrosion inhibitor is adopted, Al < + > sites in an aluminum surface solution can be combined with sulfur atoms to form coordinate bonds, and molecules are directionally adsorbed to the aluminum surface. Sulfur can form a coordination intermediate with metal ions in pollutants due to the strong coordination capacity, the binding energy of the sulfur and an aluminum matrix is reduced, so that the dissolution of the chelating agent to the pollutants is promoted, hydroxyl on a pyranose ring can form a hydrogen bond network with a hydroxylation layer on the aluminum surface, the adhesive force of molecules and an oxidation film is enhanced, and the corrosion inhibition effect is enhanced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of semiconductor manufacturing process, and particularly relates to a corrosion-inhibiting enhanced chip cleaning agent, a preparation method and application thereof. BACKGROUND

[0002] In semiconductor manufacturing, aluminum (Al) is widely used in metal interconnection layer process due to its excellent electrical conductivity and low cost characteristics. After the etching process is completed, most photoresists can be removed by a chemical stripper solution or by an oxygen plasma ashing treatment. However, highly cross-linked organic metal residues (such as fluorine-containing polymers, metal oxides) generated after dry etching are difficult to completely remove by traditional cleaning processes, and the metal organic polymers formed on the sidewalls of the substrate can easily cause uneven deposition of subsequent film layers, increase contact resistance, and even cause device short circuit. At the same time, Al material itself is sensitive to chemical corrosion, and traditional cleaning solutions (such as fluorine-containing systems) can cause irreversible damage to the Al layer while removing residues. SUMMARY

[0003] The technical problem solved by the present application is that the current aluminum process chip cleaning agent has residues of metal organic polymers after etching, which causes corrosion problems on metal substrates such as aluminum, aluminum / copper, aluminum / silicon, aluminum / silicon / copper, etc.

[0004] In view of the technical problems existing in the prior art, the present application designs a corrosion-inhibiting enhanced aluminum process chip cleaning agent which can remove metal organic polymers after etching and has almost no corrosion on metal substrates such as aluminum, aluminum / copper, aluminum / silicon, aluminum / silicon / copper, etc.

[0005] It should be noted that in the present application, unless otherwise specified, the specific meaning of "including" involved in the composition limitation and description includes both open-ended "including", "containing" and the like and their similar meanings, and also includes closed-ended "consisting of" and the like and their similar meanings.

[0006] In order to solve the above-mentioned technical problems, the present application adopts the following scheme:

[0007]

First technical solution

[0008] A corrosion-inhibiting enhanced chip cleaning agent, characterized in that it comprises the following components in terms of weight parts:

[0009] 0.001-0.01 parts of pyranoside corrosion inhibitor;

[0010] 0.1-0.5 parts of chelating agent;

[0011] 0.1-2 parts of organic acid;

[0012] 0.1-2 parts of fluoride;

[0013] Organic solvent 60-90 parts;

[0014] Ultra-pure water 20-50 parts;

[0015] The pyranoside corrosion inhibitor is an alkylthiopyranoside.

[0016] Further, the alkylthiopyranoside is one or more of ethyl β-D-thiopyranoglucoside, octyl-β-D-thiopyranoglucoside, octyl-β-D-thiopyranogalactoside, heptyl-β-D-thiopyranoglucoside.

[0017] Further, the chelating agent is a double imidazole ring structure organic matter.

[0018] Further, the double imidazole ring structure organic matter is one or more of 2,2-dimethyl imidazole methane, benzimidazole, 1,1'-carbonyl di(2-methyl imidazole), di(1H-imidazol-1-yl) methanimine.

[0019] Further, the organic acid is one or more of maleic acid, tartaric acid, gluconic acid, lactic acid, adipic acid, glutaric acid, citric acid.

[0020] Further, the fluoride is one or more of ammonium fluoride, ammonium tetrafluoroborate, ammonium trifluoroacetate, ammonium fluorosilicate, tetrabutylammonium tetrafluoroborate.

[0021] Further, the organic solvent is one or more of ethyl acetate, tetrahydrofuran, dimethyl sulfoxide, acetone.

[0022] In the present application, in order to further optimize the performance of the corrosion inhibition enhanced chip cleaning agent, the components can be optimized, the pyranoside corrosion inhibitor is 0.001-0.005 parts; the chelating agent is 0.1-0.3 parts; the organic acid is 0.1-0.5 parts; the fluoride is 0.1-1 parts; the organic solvent is 70-80 parts; the ultra-pure water is 25-35 parts.

[0023] In the present application, the pyranoside corrosion inhibitor is ethyl β-D-thiopyranoglucoside (CAS: 7473-36-1).

[0024] In the present application, the chelating agent is preferably di(1H-imidazol-1-yl) methanimine.

[0025] In the present application, the organic acid is preferably citric acid.

[0026] In the present application, the fluoride is preferably ammonium fluoride.

[0027] In the present application, the organic solvent is preferably dimethyl sulfoxide.

[0028] In this invention, the pyranoside corrosion inhibitors in the corrosion-enhancing chip cleaning agent have a unique function:

[0029] The sulfur atom in alkyl thiopyranoside contains two lone pairs of electrons, and the Al³⁺ in the aluminum surface solution + The sites can bind to sulfur atoms to form Al←S coordination bonds, allowing molecules to be directionally adsorbed onto the aluminum surface. The strong coordinating ability of sulfur atoms can form coordination intermediates with metal ions in pollutants, reducing their binding energy with the aluminum matrix and thus promoting the dissolution of pollutants. The hydroxyl groups on the pyranoside can form a hydrogen bond network with the hydroxylated layer (Al-OH) on the aluminum surface, enhancing the adhesion between the molecules and the oxide film, thereby enhancing the corrosion inhibition effect.

[0030] In this invention, the chelating agent in the corrosion-inhibiting and enhanced chip cleaning agent plays a unique role:

[0031] Through the diimidazole ring structure and Al³ + This forms a multidentate chelate complex, generating a highly stable cyclic compound. This chelating agent can chelate free Al³⁺ in metal residues. + It can also form a chelating film on the surface of metallic aluminum, which can play a certain role in corrosion inhibition.

[0032] Alkyl thiopyranoside corrosion inhibitors construct an initial protective layer on the metal surface through their thiol and glycoside structures. A chelating agent with a diimidazole ring structure reduces the concentration of aluminum ions in the solution and strengthens the film through nitrogen atom coordination. Together, they form a composite protective system with both high adhesion and impermeability. This synergistic effect not only improves corrosion inhibition efficiency but also enhances the adaptability of the cleaning agent in complex corrosive environments.

[0033] [Second Technical Solution]

[0034] A method for preparing the above-mentioned corrosion-inhibiting and enhanced chip cleaning agent includes the following steps:

[0035] Step 1: Weigh out the respective amounts of each component;

[0036] Step 2: Mix ultrapure water, organic acid and fluoride evenly to obtain solvent one;

[0037] The organic solvent, the pyranoside corrosion inhibitor, and the chelating agent are mixed evenly to obtain solvent two;

[0038] Step 3: Mix solvent one and solvent two at room temperature and stir until all materials are completely dissolved to obtain the corrosion-inhibiting and enhanced chip cleaning agent.

[0039] [The third technical solution]

[0040] A method for using the above-mentioned corrosion-inhibiting enhanced chip cleaning agent, comprising the following steps:

[0041] Step 1: heat the corrosion-inhibiting enhanced chip cleaning agent to 40-60℃, then spray it onto the semiconductor chip, and the spraying time is 5-15 minutes, to obtain the cleaned semiconductor chip;

[0042] Step 2: put the cleaned semiconductor chip into ultrapure water for washing at least twice, and dry it with nitrogen, to complete the cleaning process of the semiconductor chip.

[0043]

Fourth technical solution

[0044] The use of the above-mentioned corrosion-inhibiting enhanced chip cleaning agent in cleaning semiconductor chips.

[0045] The present application provides a corrosion-inhibiting enhanced chip cleaning agent, a preparation method and application, which have the following beneficial effects:

[0046] 1. In the alkyl thio pyranoside corrosion inhibitor in the present application, the sulfur atom contains two pairs of lone pair electrons, and the Al³ + site in the aluminum surface solution can combine with the sulfur atom to form an Al←S coordination bond, so that the molecule is oriented and adsorbed on the aluminum surface. The strong coordination ability of the sulfur atom can form a coordination intermediate with the metal ions in the pollutants, reducing the binding energy with the aluminum matrix, thereby promoting the dissolution of the chelating agent to the pollutants. The hydroxyl group on the pyranose ring can form a hydrogen bond network with the hydroxylated layer (Al-OH) on the aluminum surface, enhancing the adhesion of the molecule to the oxide film, thereby enhancing the corrosion inhibition effect.

[0047] 2. The chelating agent of the cleaning agent in the present application is a double imidazole ring structure organic matter, and the nitrogen coordination atoms in the molecule can form a polydentate chelate complex with Al³ + , to generate a high-stability ring compound. The chelating agent can not only chelate free Al³ + in the metal residue to remove the metal-organic polymer after etching, but also form a surface chelate film on the surface of the metal aluminum to replace the weakly adsorbed water molecules or corrosion medium, thereby playing a certain corrosion inhibition effect. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 : SEM image of the chip before cleaning, magnified 8000 times;

[0049] Figure 2 : SEM image of the chip after cleaning with the cleaning agent prepared in Example 1, magnified 8000 times;

[0050] Figure 3 : SEM image of the chip after cleaning with the cleaning agent prepared in Comparative Example 1, magnified 8000 times. DETAILED DESCRIPTION

[0051] The application will be further described in connection with the specific embodiments and the accompanying drawings:

[0052] In the application, examples 1-7 and comparative examples 1-5 disclose various corrosion-inhibiting enhanced chip cleaning agents, which contain components and mass ratios as shown in Table 1 and Table 2.

[0053] Table 1: Examples 1-7 of corrosion-inhibiting enhanced chip cleaning agents

[0054] Table 2: Comparative examples 1-5 of corrosion-inhibiting enhanced chip cleaning agents

[0055] The preparation method of the corrosion-inhibiting enhanced chip cleaning agent of the application is as follows:

[0056] Step 1: weigh each component according to the respective amount;

[0057] Step 2: mix the ultrapure water, organic acid and fluoride uniformly to obtain solvent one;

[0058] Mix the organic solvent, the pyranoside corrosion inhibitor and the chelating agent uniformly to obtain solvent two;

[0059] Step 3: mix and stir solvent one and solvent two at room temperature until all the materials are completely dissolved, and the corrosion-inhibiting enhanced chip cleaning agent is obtained.

[0060] The use method of the corrosion-inhibiting enhanced chip cleaning agent of the application is as follows:

[0061] Step 1: heat the corrosion-inhibiting enhanced chip cleaning agent to 40-60℃, then spray it onto the semiconductor chip, and the spraying time is 5-15 minutes to obtain the cleaned semiconductor chip;

[0062] Step 2: put the cleaned semiconductor chip into ultrapure water for washing at least twice, and blow dry with nitrogen, and the cleaning process of the semiconductor chip is completed.

[0063] Performance test and description:

[0064] The performance 1 is the test method of cleaning effect:

[0065] The chip with silicon oxide as the substrate has a large amount of metal organic polymer and the like remaining on it after etching, and the chip is cleaned using the cleaning agent of the above examples and comparative examples of the application, and the cleaning process method comprises the following steps:

[0066] Step 1: The semiconductor chip cleaning agent is heated to 40℃ by a water bath, and then the semiconductor chip is placed in the rotating device of the single-chip microcomputer, and the rotating spray time is 10 minutes to obtain the cleaned semiconductor chip;

[0067] Step 2: The cleaned semiconductor chip is placed in ultrapure water and washed twice, and then dried with nitrogen, thereby completing the cleaning process of the semiconductor chip. The test results are shown in Figures 1-3 .

[0068] The ultrapure water used in steps 1 and 2 is deionized water with a resistance of at least 18MΩ.

[0069] The test method for performance 2 metal corrosion is as follows:

[0070] ICP-MS (inductively coupled plasma mass spectrometry) is used to test the corrosion performance of different cleaning agents on metals. The specific test method is as follows: 2×2cm 2 wafers (with a metal layer: Al-Cu) are placed on a mini single-chip microcomputer rotating machine, and a water bath is used to maintain the cleaning agent at 40℃ for continuous spraying for 10 minutes. Then, the film thickness of the wafers before and after spraying using the single-chip microcomputer is tested by a four-point probe instrument, so as to investigate the corrosion rate of different cleaning agents on metals. The performance test results of the cleaning agents obtained in Examples 1-7 and Comparative Examples 1-5 are shown in Table 3.

[0071] Table 3 test data

[0072] Analysis of the test results is as follows:

[0073] From the test data in Table 3, it can be seen that the cleaning agent of the present application has less corrosion on aluminum / copper metal substrates, and no metal organic polymer residue is left after cleaning.

[0074] Comparative Example 1 lacks pyranoside corrosion inhibitor, resulting in high corrosion rate of metal substrate and trace amount of metal organic polymer residue;

[0075] Comparative Example 2 does not add bis(1H-imidazole-1-yl) methanimine chelating agent, resulting in a large amount of metal organic polymer on the chip surface;

[0076] Comparative Example 3 uses inorganic acid hydrofluoric acid, resulting in an increase in the corrosion rate of the metal substrate;

[0077] Comparative Example 4 uses 2,2'-biimidazole as a chelating agent, and the chelation effect is reduced, resulting in trace amount of metal organic polymer residue on the chip surface;

[0078] Comparative Example 5 uses imidazole as a corrosion inhibitor, and the chelation effect is small, resulting in a small amount of metal organic polymer residue on the metal surface.

[0079] Further illustrated by the accompanying drawings:

[0080] Figure 1 SEM image of the chip at 8000 times magnification before cleaning; Figure 2 SEM image of the chip at 8000 times magnification after cleaning with the cleaning agent prepared according to Example 1; Figure 3 SEM image of the chip at 8000 times magnification after cleaning with the cleaning agent prepared according to Comparative Example 1.

[0081] From Figures 1-3 It can be seen that, Figure 1 the sidewall of the chip in Example 1 is covered with a large amount of residues before cleaning, Figure 2 the residues on the sidewall of the chip in Example 1 are removed completely after cleaning, Figure 3 a part of the residues on the sidewall of the chip in Comparative Example 1 are removed after cleaning, but there are still a small amount of residues, which proves that the cleaning agent of the present application has good cleaning effect and good compatibility with the metal substrate.

[0082] The above has described the present application by way of example in combination with the accompanying drawings. It is obvious that the implementation of the present application is not limited by the above-mentioned manner. Any improvement of the method concept and technical solution of the present application, or direct application of the concept and technical solution of the present application to other occasions without improvement, all fall within the protection scope of the present application.

Claims

1. A corrosion-inhibiting and enhanced chip cleaning agent, characterized in that, Based on parts by weight, it includes the following components: 0.001-0.01 parts of pyranoside corrosion inhibitor; Chelating agent 0.1-0.5 parts; Organic acids 0.1-2 parts; Fluoride 0.1-2 parts; 60-90 parts organic solvent; 20-50 parts ultrapure water; The pyranoside corrosion inhibitor is an alkyl thiopyranoside.

2. The corrosion-inhibiting and enhanced chip cleaning agent according to claim 1, characterized in that: The alkyl thiopyranoside is one or more of ethyl β-D-thiopyranoside, octyl-β-D-thiopyranoside, octyl-β-D-thiopyranoside, and heptyl-β-D-thiopyranoside.

3. The corrosion-inhibiting and enhanced chip cleaning agent according to claim 1, characterized in that: The chelating agent is an organic compound with a biimidazole ring structure.

4. The corrosion-inhibiting and enhanced chip cleaning agent according to claim 3, characterized in that: The diimidazole ring structure organic compound is one or more of 2,2-diimidazolemethane, diimidazole, 1,1'-carbonyldi(2-methylimidazole), and di(1H-imidazol-1-yl)methylimine.

5. The corrosion-inhibiting and enhanced chip cleaning agent according to claim 1, characterized in that: The organic acid is one or more of maleic acid, tartaric acid, gluconic acid, lactic acid, adipic acid, glutaric acid, and citric acid.

6. The corrosion-inhibiting and enhanced chip cleaning agent according to claim 1, characterized in that: The fluoride is one or more of ammonium fluoride, ammonium tetrafluoroborate, ammonium trifluoroacetate, ammonium fluorosilicate, and tetrabutylammonium tetrafluoroborate.

7. The corrosion-inhibiting and enhanced chip cleaning agent according to claim 1, characterized in that: The organic solvent is one or more of ethyl acetate, tetrahydrofuran, dimethyl sulfoxide, and acetone.

8. A method for preparing the corrosion-inhibiting and enhanced chip cleaning agent according to any one of claims 1-7, characterized in that... Includes the following steps: Step 1: Weigh out the respective amounts of each component; Step 2: Mix ultrapure water, organic acid and fluoride evenly to obtain solvent one; The organic solvent, the pyranoside corrosion inhibitor, and the chelating agent are mixed evenly to obtain solvent two; Step 3: Mix solvent one and solvent two at room temperature and stir until all materials are completely dissolved to obtain the corrosion-inhibiting and enhanced chip cleaning agent.

9. A method of using the corrosion-inhibiting and enhanced chip cleaning agent according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Heat the corrosion-inhibiting and enhanced chip cleaning agent to 40-60°C, and then spray it onto the semiconductor chip for 5-15 minutes to obtain the cleaned semiconductor chip; Step 2: Rinse the cleaned semiconductor chip in ultrapure water at least twice, and dry it with nitrogen gas to complete the cleaning process of the semiconductor chip.

10. The use of the corrosion-inhibiting and enhanced chip cleaner according to any one of claims 1-7 in cleaning semiconductor chips.

Images