Cleaning composition after chemical mechanical polishing and cleaning method for semiconductor device substrate

Abstract

The present invention relates to a post-chemical mechanical polishing cleaning composition and a method for cleaning semiconductor device substrates. The composition comprises at least one alkaline substance, at least one amine substance, at least one metal chelating agent substance, and at least one metal corrosion inhibitor substance. The composition is suitable for removing residues and contaminants from the surface of a semiconductor wafer after chemical mechanical polishing. The post-chemical mechanical polishing cleaning composition of the present invention has a relatively mild pH value and the ability to passivate exposed materials such as copper. The raw materials are green and readily available and do not contain highly toxic components. For post-cleaning of copper CMP, the composition can efficiently remove post-CMP contaminants of copper without generating defects or damage, and also reduces damage to low-dielectric-constant materials.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, in particular to a cleaning composition after chemical mechanical polishing and a method for cleaning a semiconductor device substrate. Background Art

[0002] As semiconductor device critical dimensions continue to shrink, technical challenges in metal interconnect structures become increasingly prominent, with RC hysteresis being a primary concern. The primary solution to this problem lies in increasing the conductivity of the interconnect metal and reducing the dielectric constant (k) of the dielectric material. Consequently, copper, with its higher conductivity, has gradually replaced aluminum as the mainstream interconnect metal in advanced devices.

[0003] In the manufacturing of deep submicron semiconductor devices, the Damascus process of copper interconnects is to form conductors by embedding copper in low-dielectric-constant materials. A key step is to perform chemical mechanical planarization (CMP) on the copper layer on the wafer surface to remove excess copper protruding from the dielectric layer surface and ensure global flatness at the wafer level to ensure the effective implementation of subsequent processes.

[0004] The CMP process involves the chemical reaction between the abrasive slurry and the material to be polished, causing the semiconductor wafer surface to rotate relative to the polishing pad after contact under controllable pressure and temperature, generating mechanical friction. This dual action of chemical reaction and mechanical force achieves thinning and flattening of the thin film on the wafer surface. CMP slurry contains abrasive particles and chemical additives. After the CMP process, a large number of removable defective substances remain on the wafer surface, including but not limited to abrasive particles, chemicals, polishing pad grinding debris, free impurities after wafer film friction, and byproducts formed from related chemical reactions. If not removed quickly, a large number of defects will be introduced into the device, reducing wafer production yield and device reliability. Therefore, the removal of these contaminants is extremely necessary.

[0005] The post-CMP cleaning step is the wafer cleaning and drying process performed within the tool's cleaning unit after the wafer completes the CMP process. This involves spraying the cleaning solution and scrubbing with a polyvinyl alcohol brush to effectively remove the contaminants mentioned above. This process is facilitated by the cleaning solution's formulation and the mechanical action of the water flow (and brush), but it also relies more heavily on chemical adjustments to the wafer surface, specifically regulating the van der Waals forces, hydrogen bonds, and electrostatic attractions between the contaminants and the wafer surface. Therefore, the electrochemical properties of the cleaning solution are also a key factor influencing cleaning performance.

[0006] The traditional copper process post-CMP cleaning solution is an acidic solution with citric acid as the main component (usually a single formula), which achieves the purpose of removing contaminants on the wafer surface by corroding and stripping the copper layer. However, metallic copper is more susceptible to corrosion under acidic conditions, causing the copper film to be etched, and is easily oxidized when subsequently exposed to air to form copper oxide. The hazards of forming this substance are threefold: first, the high resistivity of copper oxide will block the interconnection of metal wires; second, copper oxide easily reacts and dissolves in acidic solutions, causing the copper corrosion rate to increase, resulting in the loss and disconnection of extremely fine copper wires, and at the same time causing the wafer surface roughness to exceed the quality control range; third, free copper ions Cu 2+ They can adhere to the wafer surface or migrate into the silicon oxide layer, causing device electrical failure. This problem is particularly acute as technology nodes shrink below 45nm. To address these issues, the industry has gradually shifted to alkaline cleaning solutions. Alkaline conditions form a thin film of cuprous oxide on the copper surface, preventing further corrosion while maintaining electrical conductivity. Furthermore, by adding additional components to the single pH adjuster, micro-etching, complexation, and corrosion protection are achieved, achieving an optimal balance between wafer contaminant removal and metal protection. The cleaning solution used is an aqueous solution, primarily water-based, containing water-soluble functional components. For example, alkaline cleaning solutions include quaternary ammonium bases, hydroxylamine, carboxylic acids, and nitrogen heterocycles. Tetramethylammonium hydroxide is typically used as the quaternary ammonium base, which has a high pH and is highly biotoxic. This poses safety risks during use and increases wastewater treatment costs. In this field, there are generally many studies on the electrode polarization overpotential η and polarization current density i, but there is no clear report on the relationship between the two, the range of values of the a and b constants, the impact of formulation changes on the a and b constants, and how to adjust the a and b constants to achieve excellent cleaning effects. Summary of the Invention

[0007] The present invention addresses the problems existing in the prior art. By combining different raw materials and performing fitting research on the relationship between the electrode polarization overpotential η and the polarization current density i in the post-chemical mechanical polishing cleaning composition, and by controlling the parameters a and b, a post-chemical mechanical polishing cleaning composition with excellent comprehensive performance is developed.

[0008] A first aspect of the present invention provides a post-chemical mechanical polishing cleaning composition comprising 0.1 wt% to 15 wt% of one or more combinations of alkaline substances as shown in Chemical Formula 1 or Chemical Formula 2, and 0.1 wt% to 10 wt% of one or more combinations of amine substances as shown in Chemical Formula 3 or Chemical Formula 4;

[0009]

[0010] In the chemical formula 1, R1 represents a hydrogen atom, an alkane group having 1 to 4 carbon atoms, or a benzyl group, or a combination thereof; in the chemical formula 1, R2 represents an alkane group having 1 to 4 carbon atoms; n is a positive integer ranging from 1 to 4; m is a positive integer ranging from 0 to 3; and y is a positive integer, y=0 or 1;

[0011]

[0012] In the chemical formula 3, R3 represents a hydrogen atom, one or more combinations of alkane groups having 1 to 4 carbon atoms, and R4 represents one or more combinations of alkane groups having 1 to 4 carbon atoms. p is a positive integer ranging from 0 to 2, q is a positive integer ranging from 1 to 3, and x is a positive integer ranging from 1 to 5.

[0013] The post-chemical mechanical polishing cleaning composition is suitable for removing residues and contaminants from the surface of a semiconductor wafer after chemical mechanical polishing. During the process of cleaning a copper wafer using the post-chemical mechanical polishing cleaning composition, at the contact surface between the post-chemical mechanical polishing cleaning composition and the copper wafer, under strong polarization conditions, the electrode polarization overpotential η and the polarization current density i satisfy the relationship shown in the following formula (1):

[0014] η=a±b×lg|i| (1)

[0015] In the formula (1), a and b are both constants, wherein a is between -210 and -150, and b is between 110 and 220;

[0016] Furthermore, the self-corrosion potential of the post-chemical mechanical polishing cleaning composition during the cleaning of copper wafers is between -210 mV and -150 mV;

[0017] Furthermore, the alkaline substance comprises one or more combinations of the following compounds:

[0018]

[0019] Furthermore, the amine substance comprises one or more combinations of the following compounds:

[0020]

[0021] Furthermore, the present invention comprises 0.1 wt% to 10 wt% of at least one metal complexing agent, wherein the metal complexing agent comprises at least one of the following compounds: citric acid, ethylenediaminetetraacetic acid, malic acid, aminotriacetic acid, diethylenetriaminepentaacetic acid, tartaric acid, gluconic acid, glycolic acid, hydroxyethylethylenediaminetriacetic acid, hydroxyethylidenediphosphonic acid, nitrilotri(methylenephosphonic acid), ethylenediaminetetramethylenephosphonic acid, and diethylenetriaminepenta(methylenephosphonic acid);

[0022] Furthermore, it contains 0.0001 wt% to 5 wt% of at least one metal corrosion inhibitor, wherein the metal corrosion inhibitor comprises at least one of the following compounds: phenylalanine, proline, lysine, cysteine, methionine, aspartic acid, arginine, adenosine, adenine, guanine, uric acid, caffeine, theophylline, and theobromine;

[0023] Furthermore, the pH of the cleaning composition after chemical mechanical polishing is between 9 and 13, preferably, the pH is between 10 and 12.5, and particularly preferably, the pH is between 11 and 12;

[0024] A second aspect of the present invention provides a method for cleaning a semiconductor device substrate, the method comprising contacting the semiconductor device substrate with any one of the above-mentioned post-chemical mechanical polishing cleaning compositions diluted with deionized water for a period of 5 seconds to 10 minutes, rinsing the semiconductor device substrate with deionized water, and drying the semiconductor device substrate, thereby removing at least 80% of the residues and contaminants.

[0025] Furthermore, the mixing comprises one of the following mixing methods: the post-chemical mechanical polishing cleaning composition is mixed with deionized water according to a set mixing ratio, and stored in a storage tank, and the storage tank is circulated and refluxed in an uninterrupted manner; or the post-chemical mechanical polishing cleaning composition and deionized water are extracted from two pipelines respectively, and the flow rates of the post-chemical mechanical polishing cleaning composition and deionized water are controlled according to the set mixing ratio, and the two fluids are combined into the same pipeline to form two fluids, thereby achieving a mixing effect;

[0026] Furthermore, the set mixing ratio of the post-chemical mechanical polishing cleaning composition to deionized water is between 1:5 and 1:300.

[0027] Beneficial effects: The post-chemical mechanical polishing cleaning composition involved in the present invention is prepared by modifying an existing alkaline aqueous solution and controlling its a and b parameters within a certain range. The prepared post-chemical mechanical polishing cleaning composition has a relatively mild pH and the ability to passivate exposed materials such as copper. The raw materials are green and easily available and do not contain highly toxic components. For post-cleaning of copper CMP, it can efficiently remove copper post-CMP contaminants without causing defects and damage, and also reduces damage to low dielectric constant materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] Figure 1 This is a graph showing the electrode polarization overpotential η and polarization current density i for some embodiments of the present invention. DETAILED DESCRIPTION

[0030] The embodiments of the present invention will be described in detail below with reference to the examples. However, it will be understood by those skilled in the art that the following examples are intended to illustrate the present invention only and should not be construed as limiting the scope of the present invention. Where specific conditions are not indicated in the examples, the experiments were carried out under conventional conditions or under conditions recommended by the manufacturer. Where the manufacturer of the reagents or instruments is not indicated, conventional products can be obtained by commercial purchase.

[0031] Reference to "semiconductor device" in the present invention is intended to cover microelectronic device wafers used to form integrated circuits, wherein the microelectronic device wafer includes a substrate, such as silicon, on which areas are patterned for deposition of a variety of different materials having insulating, conductive and / or semiconductive properties.

[0032] In the copper damascene process commonly used for circuit metallization in microelectronic device fabrication, the layers that must be removed and planarized, i.e., polished, include a copper layer or copper wire with a thickness of 1 to 1.5 μm, and a copper seed layer with a thickness of 0.05 to 0.15 μm. The copper layer is separated from the dielectric surface material by a barrier material layer. The key to achieving good uniformity across the entire wafer surface after polishing is the use of a post-CMP cleaning composition that exhibits appropriate chemical removal selectivity for each residual substance that may remain.

[0033] Residues and contaminants as used herein refer to small particles, foreign matter, and any type of debris left on the wafer surface during any or all typical microelectronic device processing processes (including plasma etching, ashing, chemical mechanical polishing, wet etching, and post-chemical mechanical polishing cleaning, as well as combinations thereof), and the sizes of the particles can vary from a few microns down to very small particles; wherein residues and contaminants generally include all types of particles resulting from the chemistry selected for chemical mechanical polishing slurry, such particles may include reaction byproducts of the polishing slurry, chemicals from wet etching and their reaction byproducts, and other materials, such as byproducts of various device processing processes such as plasma etching or plasma ashing processes.

[0034] The "low dielectric constant material" referred to in the present invention corresponds to any material used as a node material in a layered microelectronic device, wherein the material has a dielectric constant less than 3.5, and the selected materials include but are not limited to silicon-containing organic polymers, silicon-containing organic / inorganic hybrid materials, organosilicate glass (OSG), TEOS, fluorinated silicate glass (FSG), silicon dioxide, and carbon-doped oxide (CDO) glass.

[0035] Post-chemical mechanical polishing cleaning composition

[0036] The embodiment of the present invention includes a post-chemical mechanical polishing cleaning composition, comprising 0.1 wt% to 15 wt% of one or more combinations of alkaline substances as shown in Chemical Formula 1 or Chemical Formula 2.

[0037]

[0038] Wherein, R1 in Chemical Formula 1 represents one or more combinations of a hydrogen atom, an alkane group having 1 to 4 carbon atoms, and a benzyl group; R2 in Chemical Formula 1 represents an alkane group having 1 to 4 carbon atoms; n is a positive integer ranging from 1 to 4; m is a positive integer ranging from 0 to 3; and y is a positive integer, y=0 or 1;

[0039] Preferably, the alkaline substance comprises one or more combinations of the following compounds:

[0040]

[0041] Particularly preferably, the alkaline substance comprises one or more combinations of the following compounds:

[0042]

[0043] The post-chemical mechanical polishing cleaning composition involved in the embodiment of the present invention comprises 0.1 wt % to 10 wt % of one or more combinations of amine substances as shown in Chemical Formula 3 or Chemical Formula 4;

[0044]

[0045] Wherein, R3 in Chemical Formula 3 represents a hydrogen atom, one or more combinations of alkane groups having 1 to 4 carbon atoms, R4 in Chemical Formula 3 represents one or more combinations of alkane groups having 1 to 4 carbon atoms, p is a positive integer ranging from 0 to 2, q is a positive integer ranging from 1 to 3, and x is a positive integer ranging from 1 to 5;

[0046] Preferably, the amine substance comprises one or more combinations of the following compounds;

[0047]

[0048] Particularly preferably, the amine substance comprises one or more combinations of the following compounds;

[0049]

[0050] Preferably, the ratio of the alkaline substance to the amine substance in the post-chemical mechanical polishing cleaning composition involved in the embodiments of the present invention is between 0.014 and 10.

[0051] The post-chemical mechanical polishing cleaning composition involved in the embodiment of the present invention contains 0.1wt% to 10wt% of at least one metal chelating agent substance, wherein the metal chelating agent substance includes but is not limited to citric acid, ethylenediaminetetraacetic acid, malic acid, aminotriacetic acid, diethylenetriaminepentaacetic acid, tartaric acid, gluconic acid, glycolic acid, hydroxyethylethylenediaminetriacetic acid, hydroxyethylethylenediphosphonic acid, nitrilotri(methylenephosphonic acid), ethylenediaminetetramethylenephosphonic acid, and diethylenetriaminepenta(methylenephosphonic acid); preferably, the metal chelating agent substance in the embodiment of the present invention includes but is not limited to one or more combinations of citric acid, tartaric acid, glycolic acid, hydroxyethylethylenediaminetriacetic acid, ethylenediaminetetramethylenephosphonic acid, malic acid, and aminotriacetic acid; particularly preferably, the metal chelating agent substance in the embodiment of the present invention includes one or more combinations of citric acid, tartaric acid, glycolic acid, hydroxyethylethylenediaminetriacetic acid, and ethylenediaminetetramethylenephosphonic acid.

[0052] Preferably, the ratio of the amine substance to the metal complexing agent substance in the post-chemical mechanical polishing cleaning composition involved in the embodiments of the present invention is between 0.5 and 70,000.

[0053] The post-chemical mechanical polishing cleaning composition involved in the embodiments of the present invention contains 0.0001 wt% to 5 wt% of at least one metal corrosion inhibitor substance, wherein the metal corrosion inhibitor substances include but are not limited to phenylalanine, proline, lysine, cysteine, methionine, aspartic acid, arginine, adenosine, adenine, guanine, uric acid, caffeine, and theophylline; preferably, the metal corrosion inhibitor substances in the embodiments of the present invention include but are not limited to one or more combinations of caffeine, adenosine, guanine, arginine, theophylline, cysteine, proline, and adenine; particularly preferably, the metal corrosion inhibitor substances in the embodiments of the present invention include one or more combinations of proline, lysine, cysteine, adenine, guanine, and caffeine.

[0054] According to electrochemical theory in the art, when a current passes through an irreversible electrode, the potential value of the irreversible electrode will deviate from the equilibrium value when no current passes through. In the present invention, it is found through research that a micro-electrochemical system is formed on the contact surface between the post-chemical mechanical polishing cleaning composition and the copper wafer. Under strong polarization conditions, the electrode polarization overpotential η and the polarization current density i of the micro-electrochemical system satisfy the relationship shown in the following formula (1):

[0055] η=a±b×lg|i| (1)

[0056] Wherein, a and b in formula (1) are both constants, wherein a is between -210 and -150, and b is between 110 and 220.

[0057] Among them, constants a and b are important parameters for characterizing the electrochemical performance of the electrode in the present invention, wherein a represents the overpotential of the electrode at unit current density, and b represents the degree of influence of the change of polarization current density on the overpotential of the electrode; wherein in the relationship (1), the anode current (c) and the cathode current (a) are respectively as follows: Figure 1 The relationship shown by the upper and lower hyperbolas is expressed, so the constant b is represented by βc and βa as shown in Table 2.

[0058] In the present invention, by adjusting the formula of the cleaning liquid after chemical mechanical polishing, when the constants a and b are controlled within a certain range, the cleaning liquid after chemical mechanical polishing achieves a better cleaning effect on the copper wafer.

[0059] Furthermore, the self-corrosion potential of the chemical mechanical polishing cleaning composition for copper wafers is between -210mV and -150mV, wherein the self-corrosion potential is the overpotential under unit current density, that is, when the current density is equal to 1mA / cm 2 When i=1mA / cm 2 When , the constant a is the self-corrosion potential of the copper wafer surface.

[0060] Furthermore, the pH of the cleaning composition is between 9 and 13, preferably, the pH is between 10 and 12.5, and particularly preferably, the pH is between 11 and 12.

[0061] Measurement of constants a and b

[0062] The result of the electrode polarization overpotential η and the polarization current density i in the strong polarization region of the electrochemical system satisfies η = a ± b × lg |i|.

[0063] In the small polarization region, that is, the potential range where the current density is extremely small, the electrode reaction is close to a reversible process.

[0064] In the strong polarization region, the overpotential and current density conform to the above relationship. The straight line intervals of the anode region curve and the cathode region polarization curve can be extended to intersect at one point, which corresponds to the current density when the metal corrosion reaches a steady state, that is, the corrosion current.

[0065] In the embodiment of the present invention, a test method known in the art may be used to measure the constants a and b.

[0066] As an example of a testing method, an electrochemical workstation can be used in an embodiment of the present invention to determine the relationship between the electrode polarization overpotential η and the polarization current density i. There is no special limitation on the electrochemical workstation in the present invention, and a conventional electrochemical workstation in the art can be selected.

[0067] In the embodiment of the present invention, Ag / AgCl can be used as the reference electrode, and the platinum wire and the Cu thin film wafer (a conventional 12" wafer is electrochemically deposited with a Cu thin film having a thickness of Cut into 2x2cm wafers) as the counter electrode and working electrode, respectively, and the relationship between the electrode polarization overpotential η and the polarization current density i of the Cu film in the cleaning composition after chemical mechanical polishing was studied through a three-electrode system.

[0068] In the embodiment of the present invention, a potential scan with a scanning potential range of -0.4 to 0.1 V and a scanning speed of 50 mV / s can be selected in the electrochemical workstation software. After obtaining the iV curve, the software outputs the lgi-V curve, and the a and b values can be calculated immediately.

[0069] Semiconductor device substrate cleaning method

[0070] The semiconductor device substrate cleaning method of the present invention can be implemented by any suitable method or manner to remove unwanted residues and contaminants from the surface of the semiconductor device substrate using the chemical mechanical polishing cleaning composition of the present invention. For example, the chemical mechanical polishing cleaning composition can be sprayed onto the cleaned device surface, or the semiconductor device substrate can be immersed in a volume of the chemical mechanical polishing cleaning composition at room temperature for 5 seconds to 10 minutes. The semiconductor device substrate can then be rinsed thoroughly with deionized water to remove at least 80% of the residues and contaminants, preferably at least 90% of the residues and contaminants, and particularly preferably at least 99% of the residues and contaminants.

[0071] Before contacting the surface of the semiconductor device, the post-chemical mechanical polishing cleaning composition of the present invention can be further diluted with deionized water. Any suitable mixing method can be selected. As an example of the mixing method, the composition can be mixed with deionized water according to a set mixing ratio and stored in a storage tank. The storage tank is circulated in an uninterrupted manner and wet nitrogen is introduced for protection to prevent product formation and concentration fluctuations; or the composition and deionized water can be extracted from two separate pipelines, and the flow rates of the composition and deionized water are controlled according to the set mixing ratio. After the two fluids are combined into the same pipeline, a mixing effect is achieved. The set mixing ratio of the post-chemical mechanical polishing cleaning composition to deionized water in the present invention is between 1:5 and 1:300.

[0072] Example

[0073] The present invention is described in detail by citing examples, but it should be understood that the invention is not limited thereto unless otherwise specified in the description.

[0074] Chemical formula and meaning:

[0075] TMAH: Tetramethylammonium hydroxide

[0076] Compound 1-1:

[0077] Compound 1-2:

[0078] Compounds 1-3:

[0079] Compounds 1-4:

[0080] Compounds 1-5:

[0081] Compound 2-1:

[0082] Compound 2-2:

[0083] Compound 2-3:

[0084] Compound 2-4:

[0085] Compound 2-5:

[0086] Source of raw materials: The raw materials in the embodiments of the present invention are all from commercially available bulk chemicals.

[0087] Preparation method: According to the formula (specific components and corresponding specific contents) of each embodiment and comparative example in Table 1, the components are simply mixed.

[0088] Table 1

[0089]

[0090] Measurement of constants a and b

[0091] The relationship between the electrode polarization overpotential η and the polarization current density i was determined using an electrochemical workstation. Ag / AgCl was used as the reference electrode, and a platinum wire and a Cu thin film wafer (a conventional 12" wafer was electrochemically deposited with a Cu thin film of thickness 1.5 mm). Cut into 2x2cm wafers) as the counter electrode and working electrode, respectively, and the electrode polarization overpotential η and polarization current density i curve of Cu film in the cleaning composition after chemical mechanical polishing were studied by a three-electrode system.

[0092] In the electrochemical workstation software, a kinetic potential scan with a scanning potential range of -0.4 to 0.1 V and a scanning rate of 50 mV / s was selected. After obtaining the iV curve, the software outputted the lgi-V curve, and the a and b values were then calculated.

[0093] The test results of some embodiments are shown in Figure 1 .

[0094] Copper corrosion rate

[0095] The copper film thickness was measured using a four-probe resistivity meter, and the copper corrosion rate of the solution was calculated by the ratio of the thickness reduction to the treatment time.

[0096] Particle removal rate

[0097] The patented method disclosed in Chinese invention application CN110398500A was selected to test the ability of different cleaning compositions to remove residues and contaminants from Cu thin film wafers.

[0098] Organic residue removal

[0099] The organic residues removed by the cleaning solution are mainly insoluble metal organic complexes, with Cu-BTA complex being the most common. Therefore, this determination method uses Cu-BTA complex as a standard substance to examine the cleaning composition's ability to remove it. By mixing equivalent amounts of CuSO4 and BTA in an aqueous solution (5wt%), a dark green suspension is obtained. The cleaning composition is diluted to a concentration of 1 / 30 with electronic grade deionized water. The suspension is continuously and quantitatively added until the solution begins to become turbid, which is recorded as the experimental termination point. After each quantitative addition of the suspension, the solution is placed in a spectrophotometer for absorbance detection. According to the Lambert-Beer law,

[0100] A=lg(1 / T)=kbc

[0101] The absorbance A is logarithmically related to the transmittance T and is proportional to the concentration c of the absorbing substance (k is the molar absorption coefficient and b is the thickness of the absorbing layer). 2+ This product, identified as the product of Cu-BTA dissolution, can be used to characterize the cleaning composition's ability to remove Cu-BTA complexes. By recording the total volume of the dissolved Cu-BTA suspension, the ability of the post-CMP cleaning compositions to remove organic residues can be compared. Spectrophotometric analysis at a wavelength of 612 nm was used, and differences in absorbance were compared to determine the post-CMP cleaning composition's ability to remove organic residues.

[0102] Chemical Mechanical Polishing Application Verification

[0103] The performance of the cleaning composition after polishing was evaluated under the following test conditions:

[0104] The test machine is AMAT Refelxion (Modify 5Zone);

[0105] The polishing pad is DINGLONG's DH3000 series polishing pad;

[0106] The polishing liquid was ANJI U3061A (slurry (g): DIW (g): 30% H2O2 (g) = 1:10:0.37), with a flow rate of 300 mL / min;

[0107] The conditioning disk is Saesol Disk AJ27, 6 lbf, in-situ 100%; Platen / Head Speed = 97 / 91;

[0108] Zone Pressure: RR / Z1 / Z2 / Z3 / Z4 / Z5:5.90 / 5.10 / 2.40 / 2.15 / 2.10 / 2.20;

[0109] The wafer used is Semitech 754 Patterned wafer, Cu Blanket wafer Pre-Thickness 10-12KA.

[0110] Standardized polishing of Cu and SiO2 blanket wafers was performed. After polishing, the wafers were cleaned using the same tooling process with different cleaning compositions. After the cleaning process, the wafers were scanned for defect growth using a KLA-Tecor SURFSCAN SP2 wafer inspection system to verify the cleaning performance of the compositions.

[0111] The physical parameters and performance evaluation of the post-chemical mechanical polishing cleaning liquid involved in the examples and comparative examples are shown in Table 2.

[0112] Table 2

[0113]

[0114] The post-chemical mechanical polishing cleaning compositions involved in Examples 1 to 15 exhibited excellent particle removal rates, among which the particle removal rates in Examples 1, 6, 8, 10, 12, 14, and 15 were as high as over 99.5%. The post-chemical mechanical polishing cleaning compositions involved in Examples 1 to 15 also exhibited high organic residue removal ability, as well as appropriate copper corrosion rate and copper self-corrosion potential. In contrast, in Comparative Examples 1 and 2, a and b thereof are not within the scope of protection of this patent, and TMAH is used, and their particle removal rates are less than 97%, and their organic residue removal ability is less than 94%. In the semiconductor device substrate cleaning process, the cleaning effect cannot meet the use standard. Although the self-corrosion potential and copper corrosion rate in Comparative Example 1 are low, a large number of defects, as high as 42, occur, which is also unacceptable. Comparative Example 3 is an acidic cleaning solution, and its cleaning effect is far worse than that of the post-chemical mechanical polishing cleaning compositions involved in Examples 1 to 15.

[0115] It should be noted that, based on the explanations and elaborations of the above description, those skilled in the art may make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and equivalent modifications and variations of the present invention should also fall within the scope of protection of the claims of the present invention. Furthermore, although certain specific terms are used in this description, these terms are for convenience only and do not constitute any limitation to the invention.

Claims

1. A post-chemical mechanical polishing cleaning composition, characterized in that Contains 0.1wt%~15wt% of one or more combinations of the following alkaline substances: ； Contains 0.1wt%~10wt% of one or more combinations of the following amine substances: ； The post-chemical mechanical polishing cleaning composition is suitable for removing residues and contaminants from the surface of a semiconductor wafer after chemical mechanical polishing. During the process of cleaning a copper wafer using the post-chemical mechanical polishing cleaning composition, at the contact surface between the post-chemical mechanical polishing cleaning composition and the copper wafer, under strong polarization conditions, the electrode polarization overpotential η and the polarization current density i satisfy the relationship shown in the following formula (1): η=a±b×lg|i| (1) In the formula (1), a and b are both constants, wherein a is between -210 and -150, and b is between 110 and 220; The post-chemical mechanical polishing cleaning composition comprises 0.1 wt % to 10 wt % of at least one metal complexing agent, wherein the metal complexing agent comprises at least one of the following compounds: citric acid, ethylenediaminetetraacetic acid, malic acid, aminotriacetic acid, diethylenetriaminepentaacetic acid, tartaric acid, gluconic acid, glycolic acid, hydroxyethylethylenediaminetriacetic acid, hydroxyethylidenediphosphonic acid, nitrilotri(methylenephosphonic acid), ethylenediaminetetramethylenephosphonic acid, and diethylenetriaminepenta(methylenephosphonic acid); The post-chemical mechanical polishing cleaning composition contains 0.0001 wt% to 5 wt% of at least one metal corrosion inhibitor substance, wherein the metal corrosion inhibitor substance contains one or more combinations of proline, lysine, cysteine, adenine, guanine, and caffeine.

2. The post-chemical mechanical polishing cleaning composition according to claim 1, wherein The self-corrosion potential of the post-chemical mechanical polishing cleaning composition during the cleaning process of copper wafers is between -210mV and -150mV.

3. The post-chemical mechanical polishing cleaning composition according to claim 1, wherein The pH value of the post-chemical mechanical polishing cleaning composition is between 9 and 13.

4. The post-chemical mechanical polishing cleaning composition according to claim 1, characterized in that The pH value of the post-chemical mechanical polishing cleaning composition is between 10 and 12.

5.

5. The post-chemical mechanical polishing cleaning composition according to claim 1, characterized in that The pH value of the post-chemical mechanical polishing cleaning composition is between 11 and 12.

6. A method for cleaning a semiconductor device substrate, characterized in that: The method comprises contacting the semiconductor device substrate with the post-chemical mechanical polishing cleaning composition according to any one of claims 1 to 5, which is mixed and diluted with deionized water, for a period of 5 seconds to 10 minutes, rinsing the semiconductor device substrate with deionized water, and drying the semiconductor device substrate, thereby removing at least 80% of the residues and contaminants.

7. The method for cleaning a semiconductor device substrate according to claim 6, wherein: The mixing includes one of the following mixing methods: the post-chemical mechanical polishing cleaning composition is mixed with deionized water according to a set mixing ratio and stored in a storage tank, and the storage tank is circulated and refluxed in an uninterrupted manner; or the post-chemical mechanical polishing cleaning composition and deionized water are extracted from two pipelines respectively, the flow rates of the post-chemical mechanical polishing cleaning composition and deionized water are controlled according to the set mixing ratio, and the two fluids are combined into the same pipeline to form two fluids, thereby achieving a mixing effect.

8. The method for cleaning a semiconductor device substrate according to claim 7, wherein: The set mixing ratio of the post-chemical mechanical polishing cleaning composition to deionized water is between 1:5 and 1:300.

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