Polishing composition and application thereof

Abstract

The invention belongs to the technical field of chemical mechanical polishing, and particularly relates to a polishing composition and application thereof. According to the polishing composition, through cooperation of all the components in the polishing composition, especially cooperation of the thiopyridine compound and the anionic polymer, the polishing effect can be remarkably improved, and sinking is effectively avoided while high-speed removal of copper is achieved. According to the polishing composition, copper can be oxidized into CuO / Cu2O, nitrogen and sulfur elements carried by the thiopyridine compound can form strong coordination with copper and are adsorbed on the surface of an oxidized copper film, the anionic polymer can be adsorbed on the surface of the copper film through the charge effect, and the two substances are adsorbed on the surface of the copper film through different mechanisms to generate a reinforcing effect, so that the polishing effect is improved. And the damage force of mechanical force to the copper film in the polishing process can be resisted, so that the effect of inhibiting the occurrence of the dish-shaped depression is achieved.

Description

Technical Field

[0001] The present application belongs to the technical field of chemical mechanical polishing, and specifically relates to a polishing composition and its application. Background Art

[0002] The demand for smaller chip size and higher computing / storage capacity can be achieved by reducing line width and increasing the number of layers, which requires good flatness between chip layers. Currently, the only technology to achieve good interlayer flatness in chip manufacturing is chemical mechanical polishing (CMP).

[0003] Copper has been widely used as a wiring metal in integrated circuit manufacturing instead of aluminum, mainly due to the advantages of Cu wiring, such as lower resistivity and RC delay, and better resistance to electromigration. The dual Damascene process is used to make copper wiring layers. The general steps are as follows: a groove is etched on the dielectric layer; then a copper barrier layer such as Ta / TaN is filled in the groove. In order to improve the adhesion between copper and the groove, a copper seed layer is deposited; finally, the groove is filled with copper using electroplating; and finally, CMP of the copper wiring layer is performed.

[0004] The copper wiring layer CMP process is mainly divided into three steps: the first step is to use copper polishing liquid to quickly remove a large amount of copper under high polishing pressure; the second step is to use copper polishing liquid to remove the remaining copper and stop at the barrier layer under low polishing pressure; the third step is to use barrier layer polishing liquid to remove barrier layer metal, dielectric layer and a small amount of copper layer. The second step of polishing needs to stop on the barrier layer and try not to reduce the depth of the copper wiring in the dielectric layer groove. This requires the copper polishing liquid to have a low removal rate for the dielectric layer. In other words, the copper polishing liquid is required to have a high selectivity for the dielectric layer and copper. This characteristic of the copper polishing liquid causes a depression on the surface of the dielectric layer medium and the copper medium after the second step of polishing. Another depression comes from the excessive polishing of the dielectric layer between the wiring metal by CMP. The generation of depressions leads to a reduction in the width of the copper wiring and an increase in resistivity.

[0005] In order to avoid the occurrence of dishing, existing patent documents disclose a chemical mechanical polishing composition that can achieve high-speed removal of copper and has low surface dishing and good intra-wafer non-uniformity after polishing. However, the ability to inhibit the occurrence of dishing needs to be further improved. Summary of the invention

[0006] Therefore, the technical problem to be solved by the present application is to overcome the defects of the polishing effect of the polishing liquid in the prior art that needs to be further improved, thereby providing a polishing composition and its application.

[0007] To this end, this application provides the following technical solutions: According to one aspect of the present application, a polishing composition is provided. The polishing composition includes abrasive particles, an oxidizing agent, a complexing agent, a corrosion inhibitor, a thiopyridine compound, a pH regulator, an anionic polymer, and deionized water. Wherein, based on the total mass of the polishing composition, the mass percentage content of the thiopyridine compound is 0.001 wt% - 0.1 wt%; the mass percentage content of the anionic polymer is 0.001% - 0.1 wt%.

[0008] As an example, the addition amount of the thiopyridine compound can be 0.001 wt%, 0.003 wt%, 0.005 wt%, 0.008 wt%, 0.01 wt%, 0.02 wt%, 0.03 wt%, 0.04 wt%, 0.05 wt%, 0.06 wt%, 0.07 wt%, 0.08 wt%, 0.09 wt%, 0.1 wt% of the mass of the polishing composition, or within the range composed of any of the above values. As an example, the addition amount of the anionic polymer can be 0.001 wt%, 0.003 wt%, 0.005 wt%, 0.008 wt%, 0.01 wt%, 0.02 wt%, 0.03 wt%, 0.04 wt%, 0.05 wt%, 0.06 wt%, 0.07 wt%, 0.08 wt%, 0.09 wt%, 0.1 wt% of the mass of the polishing composition, or within the range composed of any of the above values.

[0009] In the present application, through the cooperation of the components in the polishing composition, especially the cooperation of the thiopyridine compound and the anionic polymer, the polishing effect can be significantly improved. While ensuring the removal rate of copper, the occurrence of dents can be avoided to the greatest extent. In the present application, the polishing composition can oxidize copper into CuO / Cu2O. The "nitrogen and sulfur" elements carried by the thiopyridine compound can form strong coordination with copper and adsorb on the surface of the oxidized copper film. The anionic polymer can adsorb on the surface of the copper film through charge interaction. The above two substances adsorb on the surface of the copper film through different mechanisms, producing a reinforcing effect, which can resist the destructive force of the mechanical force during the polishing process on the copper film, thereby achieving the effect of significantly suppressing the occurrence of dish-shaped dents. Due to the solubility of such substances, the content of the thiopyridine compound should not be too high, and too low an addition amount will not achieve the effect described in the present application. The content of the anionic polymer should not be too high. Too high an addition amount will result in too low a copper removal rate, and too low an addition amount will not achieve the effect described in the present application.

[0010] In some alternative embodiments, the polishing composition comprises components in the following mass percentages: 0.01 wt% - 0.5 wt% of abrasive particles, 0.1 wt% - 5 wt% of an oxidizing agent, 0.1 wt% - 5 wt% of a complexing agent, 0.01 wt% - 0.5 wt% of a corrosion inhibitor, 0.001 wt% - 0.1 wt% of a thiopyridine compound, 0.01 wt% - 1 wt% of a pH regulator, 0.001% - 0.1 wt% of an anionic polymer, and the balance being deionized water.

[0011] In some alternative embodiments, the thiopyridine compound includes at least one of (4-thiopyridine)acetic acid, 3-(2-pyridyldithio)propionic acid, pyridine-2-thioamide, 4-pyridylthioacetic acid hydrochloride, pyridine-3-thioamide, 2,6-dichloropyridine-4-thioamide, ethyl 2-pyridyldithiocarbamate, 2-ethylpyridine-4-thiocarboxamide, 2,2'-dithiobipyridine, 3-(methylthio)pyridine (CAS: 18794-33-7), 2-(methylthio)pyridine, 4,4'-dithiobipyridine; optionally, the thiopyridine compound includes (4-thiopyridine)acetic acid and 3-(methylthio)pyridine.

[0012] In some alternative embodiments, the anionic polymer includes at least one of polyacrylic acid, acrylic acid-acrylate copolymer, anionic polyacrylamide, alkyl sulfonic acid and its salts, alkyl benzene sulfonic acid and its salts, alkyl sulfuric acid and its salts, alkylphenol polyoxyethylene ether sulfate and its salts, alkyl ether polyoxyethylene ether sulfate and its salts, alkylphenol polyoxyethylene ether phosphate and its salts, alkyl ether polyoxyethylene ether phosphate and its salts; In some alternative embodiments, the number average molecular weight of the anionic polymer is 200 - 1,000,000, optionally 200 - 100,000. As an example, the number average molecular weight of the anionic polymer can be 200, 1000, 5000, 8000, 10000, 13000, 15000, 20000, 30000, 50000, 70000, 90000, 100000, 150000, 200000, 250000, 300000, 350000, 400000, 450000, 500000, 1,000,000, or within the range composed of any of the above values. If the molecular weight of the anionic polymer is too low, the ability of the polymer to inhibit pits is weakened, and if the molecular weight is too high, it is difficult to disperse well in water.

[0013] In some optional embodiments, the abrasive particles include at least one of silica particles, zirconia particles, cerium oxide particles, alumina particles, and silicon carbide particles; optionally, the abrasive particles include silica particles; further optionally, the silica particles are silica sols prepared by any one of the elemental silicon method, ion exchange method, and sol-gel method, optionally ion exchange method silica sol.

[0014] In the present application, silica particles are softer than alumina particles and have fewer polishing defects, and are more stable than cerium oxide and silicon carbide particles. The silica sol prepared by the ion exchange method is softer than the elemental silicon method and has no elemental silicon impurities, and has a cost advantage compared to the sol-gel method. There is no particular limitation on the specific preparation method of the abrasive particles. The specific preparation method can refer to the prior art or directly purchase the corresponding abrasive on the market.

[0015] In some optional embodiments, the silica particles are spherical particles or non-spherical particles with an association degree of 2-4, optionally spherical particles.

[0016] In the present application, the term "association" refers to multiple abrasive particles physically combined together during the preparation process, and the "association degree" refers to the number of abrasive particles physically combined together. The association degree of the abrasive particles can be confirmed by taking TEM images of the morphology of the abrasive particles. Compared with high-association particles, spherical particles are more likely to obtain a higher polishing rate.

[0017] In some optional embodiments, the D50 size of the abrasive particles is 10-300 nm, optionally 40-120 nm. In the present application, the D50 size of the abrasive particles can be measured by dynamic light scattering.

[0018] As an example, the mass percentage of the abrasive particles in the polishing composition can be 0.01 wt%, 0.05 wt%, 0.1 wt%, 0.15 wt%, 0.2 wt%, 0.25 wt%, 0.3 wt%, 0.35 wt%, 0.4 wt%, 0.45 wt%, 0.5 wt%, or within the range composed of any of the above values; the D50 size of the abrasive particles can be: 20 nm, 50 nm, 75 nm, 100 nm, 120 nm, 150 nm, 180 nm, 200 nm, 230 nm, 250 nm, 270 nm, 285 nm, 300 nm, preferably 40-120 nm. In the present application, if the size of the abrasive particles is too small, it will affect the polishing rate and is not conducive to cleaning after polishing. If the size is too large, it is likely to cause polishing defects.

[0019] In some alternative embodiments, the oxidizing agent includes hydrogen peroxide. As an example, the mass percentage content of the oxidizing agent in the polishing composition can be 0.1 wt%, 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5 wt%, or within the range composed of any of the above values; in the present application, the oxidizing agent hydrogen peroxide can first oxidize copper to CuO / Cu2O to form a softened copper oxide film, and this oxide film can be removed by subsequent mechanical action and the complexing action of the complexing agent. If too little hydrogen peroxide is added, the removal rate of copper will be affected, and the surface roughness of the polished copper will increase. If the addition amount is too high, the oxide film formed on the copper surface will be too dense, which is also not conducive to polishing and will also inhibit the removal rate of copper.

[0020] In some alternative embodiments, the complexing agent includes at least one of glycine, malonic acid, citric acid, oxalic acid, valine, alanine, threonine, ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetate, dipotassium ethylenediaminetetraacetate, cyanoacetic acid, ethylenediaminetetramethylenephosphonic acid, sodium ethylenediaminetetramethylenephosphonate, aminotrimethylenephosphonic acid; optionally, the complexing agent includes at least one of glycine, valine or ethylenediaminetetraacetic acid, and more optionally, the complexing agent includes valine or glycine.

[0021] As an example, the mass percentage content of the complexing agent in the polishing composition can be 0.1 wt%, 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5 wt%, or within the range composed of any of the above values. The addition of the complexing agent in the polishing composition is beneficial to complexing the free copper ions in the polishing liquid and promoting the removal of copper. However, if too much complexing agent is added, the surface roughness of the polished surface will increase, and if too little is added, the removal rate of copper will be affected. In the present application, by optimizing the complexing agent, the removal rate of copper can be further improved.

[0022] In some alternative embodiments, the corrosion inhibitor includes at least one of aspartic acid, glutamic acid, cysteine, tetrazole, 2-aminopyrrole, pyrazole, imidazole, 1,2,4-triazole, 3-amino-1,2,4-triazole, benzotriazole, cytosine, uracil, 2-methyl-4-isothiazolin-3-one (CAS: 2682-20-4, methylisothiazolinone), 3,5-diaminotriazole; optionally, the corrosion inhibitor includes at least one of aspartic acid, 1,2,4-triazole, 2-methyl-4-isothiazolin-3-one.

[0023] As an example, the mass percentage content of the corrosion inhibitor in the polishing composition can be 0.01 wt%, 0.02 wt%, 0.04 wt%, 0.06 wt%, 0.08 wt%, 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, or within the range composed of any of the above values. The addition of the corrosion inhibitor in the polishing composition can form a protective film on the copper surface and reduce the surface roughness of the polished copper. Adding too much will reduce the copper removal rate, and adding too little will not achieve the effect of protecting the copper surface from chemical erosion.

[0024] In some alternative embodiments, the pH regulator includes at least one of tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, ethanolamine, diethanolamine, triethanolamine, aniline, potassium hydroxide, sodium hydroxide, guanidine compounds, and alkali metal alkoxides; optionally, the pH regulator includes at least one of tetramethylammonium hydroxide, ethanolamine, potassium hydroxide, and guanidine carbonate, and more optionally, includes at least one of tetramethylammonium hydroxide, ethanolamine, and potassium hydroxide; In some alternative embodiments, the pH of the polishing composition is 5-9.

[0025] In the present application, the addition amount of the pH regulator is associated with the pH of the polishing composition. As an example, the mass percentage content of the pH regulator in the polishing composition can be 0.01 wt%, 0.03 wt%, 0.05 wt%, 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, or within the range composed of any of the above values, as long as the pH of the polishing composition is within the above-defined range. In the present application, a pH regulator that has no effect on the copper removal rate is preferably used. If the system pH is too low, the corrosion of copper will be aggravated, and if it is too high, the copper removal rate will be low.

[0026] In the present application, the preparation method of the polishing composition is conventional in the art. For example, the abrasive particles, complexing agent, corrosion inhibitor, thiopyridine compound, anionic polymer and water can be first mixed, and the pH of the system can be adjusted using a pH regulator (the pH of the system can also be adjusted after adding an oxidant), and then an oxidant is added to obtain the polishing composition.

[0027] It should be noted that in order to reduce the experimental error caused by the decomposition of the oxidant (hydrogen peroxide) over time, the sample is used within 8 hours after preparation.

[0028] According to another aspect of the present application, there is provided an application of the above polishing composition in chemical mechanical polishing, optionally in the chemical mechanical polishing of copper interconnect structures in integrated circuit manufacturing.

[0029] In the present application, the specific application method and operating parameters of the polishing composition in the chemical mechanical polishing of copper interconnect structures in integrated circuit manufacturing are conventional in the art and are not specifically limited in the present application.

[0030] The technical solution of the present application has the following advantages: The polishing composition provided by the present application includes abrasive particles, an oxidizing agent, a complexing agent, a corrosion inhibitor, a thiopyridine compound, a pH regulator, an anionic polymer, and deionized water. Among them, based on the total mass of the polishing composition, the mass percentage content of the thiopyridine compound is 0.001 wt% - 0.1 wt%; the mass percentage content of the anionic polymer is 0.001% - 0.1 wt%. Through the cooperation of the various components in the polishing composition, especially the cooperation of the thiopyridine compound and the anionic polymer, the present application can significantly improve the polishing effect, effectively avoid the occurrence of dents while achieving high-speed removal of copper. The polishing composition of the present application can oxidize copper into CuO / Cu2O. The "nitrogen and sulfur" elements carried by the thiopyridine compound can form strong coordination with copper and adsorb on the surface of the oxidized copper film. The anionic polymer can adsorb on the copper film surface through charge interaction. The above two substances adsorb on the surface of the copper film through different mechanisms, producing a reinforcement effect, which can resist the breaking force of the mechanical force during the polishing process on the copper film, thereby achieving the effect of inhibiting the occurrence of dishing dents.

[0031] The application of the polishing composition provided by the present application has the same advantages as the above polishing composition due to the use of the polishing composition provided by the present application, and will not be elaborated here.

[0032] The additional aspects and advantages of the present application will be partially given in the following description, partially become apparent from the following description, or be understood through the practice of the present application. Detailed Embodiments

[0033] The following embodiments are provided to better further understand the present application. They are not limited to the best implementation mode, and do not constitute a limitation to the content and protection scope of the present application. Any product identical or similar to the present application obtained by anyone under the inspiration of the present application or by combining the features of the present application with other prior art features falls within the protection scope of the present application.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terms used herein are for the purpose of describing particular embodiments only and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the text of this application are intended to cover non-exclusive inclusion.

[0035] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive of other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments. The "scope" disclosed in this application is defined in the form of a lower limit and an upper limit. A given scope is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a particular scope. The scope defined in this way can include or exclude the end values and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a scope. In this application, unless otherwise stated, the numerical range "a - b" represents an abbreviated representation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0 - 5" means that all real numbers between "0 - 5" are fully listed herein, and "0 - 5" is just an abbreviated representation of these numerical combinations. Additionally, when it is stated that a certain parameter is an integer ≥2, it is equivalent to disclosing that the parameter can be, for example, the integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0036] In the description of the embodiments of this application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone.

[0037] In the description of the embodiments of this application, the term "at least one" refers to one or more than two (including two).

[0038] Unless otherwise specified, all steps of the present application can be carried out sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) carried out sequentially, or may also include steps (b) and (a) carried out sequentially. For example, it is mentioned that the method may further include step (c), indicating that step (c) can be added to the method in any order. For example, the method may include steps (a), (b), and (c), or may also include steps (a), (c), and (b), or may also include steps (c), (a), and (b), etc.

[0039] For those embodiments where specific experimental steps or conditions are not specified, the operations or conditions of the conventional experimental steps described in the literature in this field can be followed. For reagents or instruments whose manufacturers are not specified, they are all conventional reagent products that can be obtained through commercial purchase.

[0040] The following describes the present application with reference to specific embodiments. It should be noted that these embodiments are only descriptive and do not limit the present application in any way.

[0041] Examples 1 - 10 This example provides a polishing composition. The composition and dosage of each component in the formula are shown in Table 1. The oxidant is hydrogen peroxide, and the balance is deionized water. The preparation method is as follows: First, mix abrasive particles, complexing agent, corrosion inhibitor, thiopyridine compound, anionic polymer with water, add the oxidant, and use potassium hydroxide as the pH regulator to adjust the pH of the system to 7.2. The silica abrasive particles in this example are spherical particles and are obtained through commercial purchase.

[0042] Example 11 This example provides a polishing composition. The difference compared with Example 1 is that the abrasive particles are non-spherical silica particles with an association degree of 3.

[0043] Example 12 This example provides a polishing composition. The difference compared with Example 1 is that the size of the abrasive particles is 200 nm.

[0044] Example 13 This example provides a polishing composition. The difference compared with Example 1 is that the pH of the final product is 5.

[0045] Example 14 This example provides a polishing composition. The difference compared with Example 1 is that the pH of the final product is 9.

[0046] Comparative Examples 1 - 3 This comparative example provides a polishing composition, which is different from Example 1 in that the specific composition is different, as shown in Table 1 for details.

[0047] Comparative Example 4 This comparative example provides a polishing composition that does not contain an oxidizing agent as compared with Example 1.

[0048] Comparative Example 5 This comparative example provides a polishing composition, the composition of which is as follows: based on the total mass of the polishing composition, it includes 0.3 wt% of silica abrasive particles, the content of polymer 8 arm-PEG-OH is 0.005 wt%, and the structural formula of the polymer is , R2 is , p = 50, n = 4, the content of complexing agent alanine is 1 wt%, the content of corrosion inhibitor 1,2,4-triazole is 0.08 wt%, mix each component evenly, make up the balance in the formula with deionized water, and adjust the pH to 7 with potassium hydroxide.

[0049] Table 1

[0050] Note that " / " in the table represents the absence of this component.

[0051] Test Example 1. Evaluation of polishing rate During the polishing rate test, the instruments and parameters used for copper polishing are as follows: Table 2

[0052] The copper wafer for polishing is a 50000 Å copper film electroplated on a 500-micron single-crystalline silicon substrate, and the size of the copper wafer is 12 inches. On the diameter of the 12-inch wafer, starting from zero point, take a point every 1 cm in the positive and negative directions, a total of 28 points are taken, and the conductivity of the points selected on the copper wafer is measured with a four-probe conductivity meter, so as to calculate the thickness of the copper wafer. The difference in the thickness of the copper wafer before and after polishing divided by the polishing time is the polishing rate of copper.

[0053] 2. Evaluation of polishing depression Preparation method of wafer for polishing: First, grooves are etched on the silicon oxide layer. The width of the grooves is 100 μm, the depth is 500 nm, and the interval between the grooves is 100 μm. A 30-nm-thick TaN film is prepared on the patterned wafer by sputtering method, and then a 50-nm-thick copper film is prepared by sputtering method. Finally, a 10000 Å-thick copper film is prepared by electroplating method. A test pattern with a copper wire width of 100 microns, a silicon oxide wire width of 100 microns, and a line density of 50% (100 / 100) is designed. Similarly, a (10 / 90) test pattern is made. The polishing of the wafer can be entrusted to a CMP consumable manufacturer for processing and production.

[0054] Polishing conditions: The polishing pressure is 2.7 psi, the rotation speed is 77 / 71 rpm. When there is 2500 Å of copper film remaining on the wafer (the polishing machine has built-in endpoint detection), the polishing pressure is changed to 1.2 psi, and the rotation speed remains unchanged at 77 / 71 rpm. After the copper film on the wafer cannot be detected, over-polishing is carried out for 10 s, and the polishing ends.

[0055] Testing method for the depression of the patterned wafer: Use a profilometer to measure in the order of dielectric layer - copper wire depression - dielectric layer. The height difference between the surface of the dielectric layer and the lowest point of the depression is the depression.

[0056] The specific test results are shown in the following table: Table 3

[0057] From the data in the above table, it can be seen that when comparing Comparative Example 1 with Example 1, the depression level of Example 1 with the addition of an anionic polymer and a thiopyridine compound is significantly lower, indicating that this combination is very beneficial for reducing depression. When comparing Comparative Example 2, Comparative Example 3 with Example 1, in Example 1 with the simultaneous addition of an anionic polymer and a thiopyridine compound, the depression level is significantly lower than that of Comparative Example 2 and Comparative Example 3 with the addition of the above single substances. This shows that the combination of an anionic polymer and a thiopyridine compound can achieve a better low-depression effect. When comparing Comparative Example 4 with Example 1, the copper polishing rate of Comparative Example 1 without hydrogen peroxide is extremely low and cannot be practically applied. When comparing Comparative Example 5 with the example, the ability to reduce depression is weak.

[0058] Obviously, the above embodiments are only examples clearly described and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A polishing composition, characterized in that, The polishing composition includes abrasive particles, an oxidizing agent, a complexing agent, a corrosion inhibitor, a thiopyridine compound, a pH regulator, an anionic polymer, and deionized water. Among them, based on the total mass of the polishing composition, the mass percentage content of the thiopyridine compound is 0.001 wt% - 0.1 wt%; the mass percentage content of the anionic polymer is 0.001% - 0.1 wt%.

2. The polishing composition according to claim 1, wherein It includes components with the following mass percentage contents: 0.01 wt% - 0.5 wt% of abrasive particles, 0.1 wt% - 5 wt% of an oxidizing agent, 0.1 wt% - 5 wt% of a complexing agent, 0.01 wt% - 0.5 wt% of a corrosion inhibitor, 0.001 wt% - 0.1 wt% of a thiopyridine compound, 0.01 wt% - 1 wt% of a pH regulator, 0.001% - 0.1 wt% of an anionic polymer, and the balance is deionized water.

3. The polishing composition according to claim 1 or 2, characterized in that, The thiopyridine compound includes at least one of (4-thiopyridine) acetic acid, 3-(2-pyridyldithio) propionic acid, pyridine-2-thioamide, 4-pyridylthioacetic acid hydrochloride, pyridine-3-thioamide, 2,6-dichloropyridine-4-thioamide, ethyl 2-pyridyldithiocarbamate, 2-ethylpyridine-4-thioformamide, 2,2'-dithiobipyridine, 3-(methylthio) pyridine, 2-methylthio pyridine, 4,4'-dithiobipyridine.

4. The polishing composition according to claim 1 or 2, characterized in that, The anionic polymer includes at least one of polyacrylic acid, acrylic acid-acrylate copolymer, anionic polyacrylamide, alkyl sulfonic acid and its salts, alkyl benzene sulfonic acid and its salts, alkyl sulfuric acid and its salts, alkylphenol polyoxyethylene ether sulfate and its salts, alkyl ether polyoxyethylene ether sulfate and its salts, alkylphenol polyoxyethylene ether phosphate and its salts, alkyl ether polyoxyethylene ether phosphate and its salts; and / or, the number average molecular weight of the anionic polymer is 200 - 1,000,000.

5. The polishing composition according to claim 1 or 2, characterized in that, The abrasive particles include at least one of silica particles, zirconia particles, ceria particles, alumina particles, silicon carbide particles; and / or, the D50 size of the abrasive particles is 10 - 300 nm.

6. The polishing composition according to claim 1 or 2, wherein The oxidizing agent includes hydrogen peroxide.

7. The polishing composition according to claim 1 or 2, characterized in that, The complexing agent includes at least one of glycine, malonic acid, citric acid, oxalic acid, valine, alanine, threonine, ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetate, dipotassium ethylenediaminetetraacetate, cyanoacetic acid, ethylenediaminetetramethylenephosphonic acid, sodium ethylenediaminetetramethylenephosphonate, aminotrimethylenephosphonic acid.

8. The polishing composition according to claim 1 or 2, characterized in that, The corrosion inhibitor includes at least one of aspartic acid, glutamic acid, cysteine, tetrazole, 2-aminopyrrole, pyrazole, imidazole, 1,2,4-triazole, 3-amino-1,2,4-triazole, benzotriazole, cytosine, uracil, 2-methyl-4-isothiazolin-3-one, 3,5-diaminotriazole.

9. The polishing composition according to claim 1 or 2, characterized in that, The pH regulator includes at least one of tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, ethanolamine, diethanolamine, triethanolamine, aniline, potassium hydroxide, sodium hydroxide, guanidine compounds, alkali metal alkoxides; and / or, the pH of the polishing composition is 5 - 9.

10. Application of a polishing composition in chemical mechanical polishing, characterized in that, The polishing composition is the polishing composition according to any one of claims 1-9.

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