Polishing composition and method of use thereof

Abstract

The present disclosure provides a chemical mechanical polishing composition and a method for polishing a polysilicon film at a high removal rate. The composition comprises 1) an abrasive; 2) at least one compound of structure (I); 3) at least one compound of structure (II); and 4) water; wherein the composition does not include tetramethylammonium hydroxide or its salts. The variables n, R 1 -R 7 , X, Y and Z 1 -Z 3 are defined in this patent specification. The synergistic effect of the compounds of structures (I) and (II) in these chemical mechanical polishing compositions results in a high polysilicon film material removal rate during polishing.

Description

[0001] Division Statement

[0002] This application is a divisional application of a patent application for invention that is a PCT international application with an application date of March 27, 2018 and an international application number of PCT / US2018 / 024543, which enters China (the entry date is September 24, 2019, the application number is 201880020925.9, and the invention title is "Polishing Composition and Method of Using the Same"). Technical Field

[0003] The present disclosure relates to a polishing composition and a method of polishing a semiconductor substrate using the composition described herein. More particularly, the present disclosure relates to a chemical mechanical polishing composition and a method for removing a polysilicon layer from a semiconductor substrate. Background Art

[0004] In the semiconductor industry, chemical mechanical polishing compositions are used in a process called chemical mechanical polishing / planarization (CMP). Together with lithographic patterning and deposition, CMP is one of the three key enabling process steps in the integrated circuit (IC) manufacturing process flow. Modern ICs are built on the surface of a common silicon wafer substrate in a side-by-side manner, typically hundreds at a time. Lithography, deposition, CMP, and multiple auxiliary steps are repeatedly applied to the wafer surface where the evolving IC structure is located until the final IC device is complete and ready to have the wafer diced into individual die (chips) for packaging. Summary of the Invention

[0005] In this technical process flow, one purpose of the CMP step is to reduce the overlying layer from the foregoing deposition step to a specific layer thickness determined by the integration scheme and to produce a flat wafer surface so that subsequent lithography steps can be performed. CMP achieves this purpose by polishing the wafer surface in a mechanical polishing machine. The polishing process includes holding the wafer in a rotating chuck (called a polishing head) and pressing the wafer against a flexible, felt-like polishing pad rotating on a polishing table (platen) using a preselected pressure (downforce), while applying an abrasive slurry (i.e., a chemical mechanical polishing composition) between the wafer surface and the polishing pad.

[0006] For a CMP process based on a specific chemical mechanical polishing composition, some generally desired performance metrics are: 1) high removal rate related to fab throughput efficiency; 2) high polish selectivity related to the ability of the CMP process to stop on certain materials selected as stop layers within the device layer stack; 3) low levels of defects (scratches, debris, remaining polish particles) related to improving final device yield; and 4) uniform material removal on the wafer surface related to the wafer being properly planarized for subsequent lithography steps. Uniform material removal within the die and across the wafer is also important for performance reproducibility and reliability within the die and wafer devices.

[0007] Polycrystalline silicon or polysilicon (P-Si) is a material widely used in semiconductor industry IC manufacturing, playing different roles in logic integration schemes and memory integration schemes, the scope of which depends on the doping level ranging from conductor to insulator. In integration schemes for logic applications, it is widely used as the gate electrode material for MOSFET / FinFET type devices. In terms of memory, polysilicon serves as parts of capacitor, gate, and contact plug structures, as can be seen, for example, in DRAM integrated circuits. Silicon nitride (SiN) is another commonly used material in IC manufacturing. It is a versatile dielectric used in situations where the default dielectric material, i.e., silicon oxide, cannot be used due to multifunctional or process limitations. In the logic aspect of the semiconductor industry, silicon nitride is widely used as a gate insulating material; in terms of memory, especially in DRAM, it is commonly used as a capacitor material. US4897702 gives examples of DRAM (memory type) devices using P-Si and SiN with the above-mentioned properties.

[0008] One of the requirements for polysilicon CMP in modern DRAM process flows is a high polysilicon removal rate (e.g., >8000 Å / min) at low to mid - lower pressure (<3 psi). The high polysilicon removal rate is determined by the need to remove extremely high polysilicon overcoat layers in a short processing time. Reducing the polishing process time is an important way to improve fab manufacturing throughput efficiency. A relatively low down pressure is needed to drive the minimization of scratch defects associated with using higher down pressures and to maximize the retention of the functional stop layer thickness / budget critical for device performance.

[0009] In the case of DRAM applications, when the stop layer is typically silicon nitride, another requirement for the DRAM polysilicon CMP process is a high polysilicon to silicon nitride removal rate selectivity (e.g., >100:1). This level of rate selectivity ensures that polysilicon can be rapidly removed during the DRAM polysilicon CMP step until the underlying silicon nitride layer is exposed, and at this point the polishing process is stopped with minimal silicon nitride layer loss. The SiN loss needs to be retained / minimized to ensure that the device is properly covered / encapsulated by the SiN dielectric. Thus, this improves the electrical and overall performance of the DRAM device.

[0010] In addition to high polysilicon removal rates and low silicon nitride removal rates, the semiconductor industry has placed a series of additional challenging requirements on polysilicon chemical mechanical polishing compositions. These additional requirements include: 1) low health hazards to promote chemical safety in the workplace; and 2) low cost of ownership (COO), or simply put, low chemical mechanical polishing composition cost, which is achieved by formulating dilutable compositions. In response to continuous efforts to reduce costs and improve business efficiency, cost of ownership (COO) has become an important business consideration for chemical mechanical polishing compositions.

[0011] An important way to improve the COO of chemical mechanical polishing compositions is to formulate dilutable compositions, such that the chemical mechanical polishing composition supplier provides the polishing composition in a concentrated form and the customer dilutes the chemical mechanical polishing composition to a specifically designated dilution level prior to use. Typical dilution levels vary widely from 2X to greater than 10X in some cases.

[0012] Regarding health and chemical safety, reducing employee exposure to chemical hazards and toxic substances can ensure chemical safety and minimize negative health effects in the workplace. In the United States, the Globally Harmonized System (GHS) of Hazardous Substance Classification, approved by the OSHA Hazard Communication Standard 29 CFR 1910.1200, provides a framework for understanding and communicating the degree of health hazards associated with various chemical substances. Chemical substances with acute toxicity are classified, where Category 1 indicates the highest health hazard and Category 5 indicates the lowest health hazard.

[0013] Substances that are effectively excluded are carcinogens classified as GHS Category 1 and 2, reproductive hazard factors classified as GHS Category 1 and 2, acute toxicity substances with GHS Category 1 and 2, and sensitizing substances with GHS Category 1 and 2. There is substantial pressure on consumable suppliers in the semiconductor industry to formulate products that exclude the hazardous substances listed in the above GHS categories.

[0014] Semiconductor manufacturers continue to limit the use of hazardous chemicals in their wafer fabs, particularly, in their CMP modules. CMP modules are particularly sensitive to hazardous chemicals because there are very few engineering controls to prevent the amount of hazardous chemicals released into the wastewater stream (as opposed to etching, lithography, etc.). Generally speaking, CMP polishing equipment has its plumbing system connected to a common wastewater stream. Once the wafer fab polishes a wafer, the polished CMP slurry is released into the common wastewater stream. Therefore, these hazardous chemicals are the cause of polluting the common wastewater near the wafer fab. The environmental health and safety (EHS) department of each city tests the wastewater discharged from these wafer fabs daily. Therefore, all wafer fabs expect not to be exposed to hazardous chemicals in the CMP slurries of suppliers. Other modules such as the etching module separate chemical waste, and then, it can be sent off-site for appropriate chemical treatment. In this regard, they generally do not face the environmental problems faced by CMP suppliers.

[0015] In addition to nanoparticle abrasives, the components of known chemical mechanical polishing compositions for polysilicon are chemical additives that promote the polysilicon removal rate through chemical reactions with the polysilicon film. Conventionally and historically, tetramethylammonium hydroxide (TMAH) has been the chemical additive selected in chemical mechanical polishing compositions designed for high polysilicon and single-crystalline silicon removal rates. For example, U.S. Patent Application Publication No. 2009 / 0156008 (Sakamoto et al.) describes a chemical mechanical polishing composition containing approximately 0.28% TMAH at the point of use (POU), which illustrates that the removal rate of single-crystalline silicon material is approximately 10,000 Å / minute. U.S. Patent No. 8,697,576 (Reiss et al.) describes a polysilicon chemical mechanical polishing composition containing 0.25% TMAH at the POU, which illustrates that the polysilicon removal rate is approximately 4,500 Å / minute.

[0016] Although TMAH is an efficient promoter for polysilicon and single-crystalline silicon removal rates, it is classified as a substance with acute oral and skin toxicity (GHS category 2) and specific target organ (e.g., central nervous system, thymus, or liver) toxicity (GHS category 1). TMAH was involved in multiple notable industrial accidents with three combined fatalities [Lin, Chun-Chi et al., 2010, Clinic Toxicology (48), 3, 213 - 217]. Therefore, there is a desire for a chemical mechanical polishing composition for polysilicon CMP that does not contain TMAH. Many wafer fabs also complain about TMAH entering their municipal wastewater stream and city officials demanding a ban on TMAH in the CMP slurry modules of wafer fabs.

[0017] The present disclosure provides a chemical mechanical polishing formulation and method of using the same, which exhibits a very high polysilicon removal rate (e.g., exceeding 8000 Å / min), and a high selectivity relative to silicon nitride (e.g., having a polysilicon to silicon nitride removal rate ratio > 100:1). Further, most of the components of the chemical mechanical polishing compositions described herein generally have low health hazards (e.g., classified as GHS category 3 or above). In certain specific examples, the chemical mechanical polishing composition of the present disclosure does not contain health hazard compounds not permitted in the CMP module of a semiconductor wafer fab (e.g., carcinogens of GHS category 1 and 2, reproductive hazard factors of GHS category 1 and 2, acute toxicity substances of GHS category 1 and 2, and sensitizers of GHS category 1 and 2). Additionally, the chemical mechanical polishing composition of the present disclosure provides a low cost of ownership (COO) by being dilutable by at least 2X.

[0018] In certain specific examples, the present disclosure features a chemical mechanical polishing composition that includes 1) at least one abrasive;

[0019] 2) at least one compound of structure (I):

[0020]

[0021] wherein n is 0, 1, 2, or 3; X and Y are each independently O(R a )、CH 2 (R a ) or NH(R a ), with the proviso that at least one (e.g., both) of X and Y is O(R a ) or NH(R a ), where each R a is independently H or optionally C 2 -C 1 -C 3 alkyl substituted with hydroxy or NH 2 ; and R 1 -R 6 are each independently H, OH, or optionally C 2 -C 1 -C 3 alkyl substituted with OH or NH 2 ; 3) at least one compound of structure (II):

[0022]

[0023] wherein Z 1 and Z 2 are each independently -CR 8 - or -N-, where R 8 is H, N(R b ) 2 、COOH、C1 -C 3 alkyl group, each R b is independently H or C 1 -C 3 alkyl group; or Z 1 and Z 2 together form a 5-6 membered ring fused to the 5-membered ring in Structure (II); Z 3 is -C- or -N-; and R 7 is H, COOH, C 1 -C 3 alkyl group or N(R 9 ) 2 wherein each R 9 is independently H or C 1 -C 3 alkyl group, with the proviso that when Z 3 is -N-, R 7 is deleted; and 4) water. The composition does not include tetramethylammonium hydroxide or its salts.

[0024] In certain specific instances, the present disclosure features a method for polishing an exposed polysilicon film on a wafer substrate surface by using the chemical mechanical polishing composition described herein to treat the polysilicon film. This method can be carried out, for example, by the following steps: A) placing the wafer in a polishing machine equipped with a polishing pad; and B) polishing the wafer using the polishing pad in the presence of the chemical mechanical polishing composition described herein. Detailed Description

[0025] The chemical mechanical polishing compositions presented in the present disclosure include abrasives that are generally insoluble in water. Accordingly, the compositions of the present disclosure can be referred to as slurries. For the purposes of the present disclosure, the terms "composition" and "slurry" and "these compositions" and "these slurries" can be used interchangeably.

[0026] The chemical mechanical polishing compositions described herein provide a high polysilicon removal rate (e.g., at least 8000 Å / minute) and a high polysilicon to silicon nitride removal rate selectivity (at least 50:1), while using components characterized by low health hazards. The chemical mechanical polishing compositions of the present disclosure can be used as an alternative to similar products that include tetramethylammonium hydroxide (TMAH) as a polysilicon removal rate promoter, where TMAH is a recognized health hazard due to its high toxicity.

[0027] Without wishing to be bound by theory, it is believed that the high polysilicon removal rate (at least 8,000 Å / minute) and / or the high polysilicon to silicon nitride removal rate ratio (e.g., at least 50:1) provided by the chemical mechanical polishing compositions of the present disclosure are achieved due to the synergistic effect between the compound of structure (I) and the compound of structure (II) during polishing. Although the mechanism of this effect is not fully understood, as demonstrated in the examples herein, high polysilicon removal rates and / or high polysilicon to silicon nitride removal rate ratios are observed when both of these components are present in the polishing formulation. In certain specific examples, when either one is omitted, the resulting polysilicon removal rate and / or polysilicon to silicon nitride removal rate ratio can be significantly reduced.

[0028] In certain specific examples, the present disclosure features a chemical mechanical polishing composition comprising 1) at least one abrasive; 2) at least one compound of structure (I):

[0029]

[0030] wherein n is 0, 1, 2, or 3; X and Y are each independently O(R a )、CH 2 (R a ) or NH(R a ), with the proviso that at least one (e.g., both) of X and Y is O(R a ) or NH(R a ), where each R a is independently H or optionally hydroxy- or NH 2 -substituted C 1 -C 3 alkyl; and R 1 -R 6 are each independently H, OH, or optionally OH- or NH 2 -substituted C 1 -C 3 alkyl; 3) at least one compound of structure (II):

[0031]

[0032] wherein Z 1 and Z 2 are each independently -CR 8 - or -N-, where R 8 is H, N(R b ) 2 , COOH, C 1 -C 3 alkyl, each R b is independently H or C 1 -C 3 alkyl; or Z1 and Z 2 together form a 5-6 membered ring fused to the 5-membered ring in Structure (II); Z 3 is -C- or -N-; and R 7 is H, COOH, C 1 -C 3 alkyl or N(R 9 ) 2 , where each R 9 is independently H or C 1 -C 3 alkyl, with the proviso that when Z 3 is -N-, R 7 is deleted; and 4) water. The composition does not include tetramethylammonium hydroxide or its salts.

[0033] As used herein, the term "C 1-3 alkyl" refers to a saturated hydrocarbon group, which can be straight-chain or branched and can have 1 to 3 carbons, such as methyl, ethyl, propyl, or isopropyl.

[0034] In certain specific instances, n in formula (I) is 0. In this specific instance, Y can be NH(R a ), where R a is H or optionally hydroxy-substituted C 1 -C 3 alkyl (e.g., hydroxyethyl); X can be O(R a ), where R a is H or optionally hydroxy-substituted C 1 -C 3 alkyl (e.g., hydroxyethyl); R 1 can be H; R 2 can be H or C 1 -C 3 alkyl (e.g., methyl or ethyl); R 3 can be H; and R 4 can be H or C 1 -C 3 alkyl (e.g., methyl). In certain specific instances, when n is 0 and R 1 -R 4 are each H, at least one of X and Y is OH.

[0035] In certain specific instances, n in formula (I) is 1. In this specific instance, Y can be NH(R a ), where R a is optionally hydroxy-substituted C 1 -C 3 alkyl (e.g., hydroxyethyl); X can be OH or NH 2 ; R1 May be H; R 2 May be H; R 3 May be H; R 4 May be H; R 5 May be H or C 1 -C 3 Alkyl (e.g., methyl); and R 6 May be H, OH and / or C 1 -C 3 Alkyl (e.g., methyl or ethyl).

[0036] In certain embodiments, R in formula (I) 1 -R 4 or R 1 -R 6 At most one of is OH or optionally OH- or NH 2 substituted C 1 -C 3 alkyl. For example, when n in formula (I) is 0, X is O(R a ) and Y is NH(R a ), R 1 -R 3 may be H and R 4 may be optionally OH- or NH 2 substituted C 1 -C 3 alkyl (e.g., methyl or ethyl). Examples of such amines include 1-amino-2-propanol and 1-amino-2-butanol. In certain embodiments, when X is NH(R a ) and Y is O(R a ), one of R 3 and R 4 is OH or optionally OH- or NH 2 substituted C 1 -C 3 alkyl; and R 3 and R 4 the other is H.

[0037] In certain embodiments, the compounds of structure (I) are amino alcohols. Exemplary amino alcohols expected to be used in the practice of the present disclosure include, but are not limited to, monoethanolamine, diethanolamine, 1-amino-2-propanol, 1-amino-2-butanol, 1,3-diamino-2-propanol, 3-amino-1,2-propanediol, 3-amino-1-propanol, 2-(2-aminoethoxy)ethanol, 2-amino-3-methyl-1-butanol, 5-amino-1-pentanol, etc.

[0038] In certain specific instances, the compound of structure (I) is a diamine. Exemplary diamines expected to be used in the practice of the present disclosure include, but are not limited to, 2,2-dimethyl-1,3-propanediamine, 1,3-diaminopentane, 2-(3-aminopropylamine)ethanol, etc.

[0039] In certain specific instances, the amount of the compound of structure (I) is at least about 0.1 wt% (e.g., at least about 0.25 wt%, at least about 0.5 wt%, at least about 0.6 wt%, at least about 0.7 wt%, at least about 0.8 wt%, at least about 0.9 wt%, at least about 1 wt%, at least about 1.25 wt%, at least about 1.5 wt%, at least about 1.75 wt%, at least about 2 wt%, or at least about 2.5 wt%, or at least about 3 wt%) to at most about 15 wt% (e.g., at most about 12.5 wt%, at most about 10 wt%, at most about 7.5 wt%, at most about 5 wt%, at most about 4 wt%, at most about 3 wt%, or at most about 2 wt%) of the CMP composition in concentrated form or in diluted point-of-use (POU) slurry form.

[0040] In certain specific instances, when Z in formula (II) 3 is -C-, one of Z 1 and Z 2 can be -N-. In this specific instance, Z 1 can be -N-; Z 2 can be -CR 8 -, where R 8 is H or NH 2 ; and R 7 can be NH 2 or COOH. In certain specific instances, when Z in formula (II) 3 is -C-, both Z 1 and Z 2 can be -N-. In this specific instance, R 7 can be NH 2 .

[0041] In certain specific instances, the compound of structure (II) is a triazole. Exemplary triazoles expected to be used in the practice of the present disclosure include, but are not limited to, benzotriazole, 3-amino-1,2,4-triazole, 3,5-diamino-1,2,4-triazole, 1,2,4-triazole-3-carboxylic acid, etc.

[0042] In certain specific instances, the compound of structure (II) is a tetrazole. Exemplary tetrazoles expected to be used in the practice of the present disclosure include, but are not limited to, 5-(aminomethyl)tetrazole, 5-methyl-1H-tetrazole, 5-aminotetrazole (ATA), its hydrates (e.g., monohydrate), etc.

[0043] It is to be understood that the tautomeric forms of the azoles of structure (II) rapidly interconvert in the aqueous chemical mechanical polishing compositions described herein and are thus equivalent to each other. All tautomeric forms of the azoles described herein are expected to be used in the CMP compositions described herein.

[0044] In certain specific instances, the amount of the compound of structure (II) is at least about 0.1 wt% (e.g., at least about 0.2 wt%, at least about 0.3 wt%, at least about 0.4 wt%, at least about 0.5 wt%, at least about 0.6 wt%, at least about 0.7 wt%, at least about 0.8 wt%, at least about 0.9 wt%, at least about 1 wt%, at least about 1.25 wt%, at least about 1.5 wt%, at least about 1.75 wt%, or at least about 2 wt%) to at most about 15 wt% (e.g., at most about 12.5 wt%, at most about 10 wt%, at most about 7.5 wt%, at most about 5 wt%, at most about 4 wt%, at most about 3 wt%, at most about 2 wt%, at most about 1 wt%, at most about 0.9 wt%, at most about 0.8 wt%, at most about 0.7 wt%, at most about 0.6 wt%, or at most about 0.5 wt%) of the CMP composition in concentrated form or in diluted point-of-use (POU) slurry form.

[0045] In certain specific instances, the abrasives expected to be used include alumina, fumed silica, colloidal silica, coated particles, titanium dioxide, cerium dioxide, zirconia, and any combination thereof. In certain specific instances, the abrasive is colloidal silica.

[0046] In addition, the silica particles expected to be used include sol-gel derived colloidal silica without surface modification and sol-gel derived colloidal silica with surface modification. The surface-modified silica can be anionic silica or cationic silica. The silica particles can include colloidal silica particles having an isotropic spherical morphology characterized by a primary particle diameter d1, or colloidal silica particles having an aggregate morphology (mainly fused dimers and trimers) characterized by a primary diameter d1 and a secondary particle diameter d2. In certain specific instances, the silica morphology type is an aggregate morphology having a primary particle diameter d1 less than 80 nm but greater than 10 nm and a secondary particle diameter d2 less than 160 nm but greater than 20 nm.

[0047] As illustrated in the examples, it is believed that an important factor contributing to the high performance of the chemical mechanical polishing compositions described herein is the unexpected synergistic effect of the compounds of structure (I) and structure (II).

[0048] In certain specific instances, the amount of the abrasive is at least about 0.05 wt% (e.g., at least about 0.10 wt%, at least about 0.25 wt%, at least about 0.5 wt%, at least about 0.75 wt%, at least about 1 wt%, at least about 1.25 wt%, at least about 1.5 wt%, at least about 1.75 wt%, at least about 2 wt%, at least about 2.5 wt%, or at least about 3 wt%) to at most about 20 wt% (e.g., at most about 15 wt%, at most about 12.5 wt%, at most about 10 wt%, at most about 7.5 wt%, at most about 5 wt%, at most about 4 wt%, at most about 3 wt%, at most about 2 wt%, or at most about 1 wt%) of the CMP composition in concentrated form or in diluted point-of-use (POU) slurry form.

[0049] In certain specific instances, the chemical mechanical polishing composition described herein may include at least one aminophosphonic acid. Suitable examples of aminophosphonic acids include, but are not limited to, ethylenediaminetetra(methylenephosphonic acid), aminotri(methylenephosphonic acid) (also referred to as aminotri(methanephosphonic acid)), diethylenetriaminepenta(methylenephosphonic acid), and salts thereof. Commercially available examples of the aminophosphonic acid include the DEQUEST series products available from Italmatch Chemicals S.P.A. (Arese, Italy). In certain specific instances, the amount of the aminophosphonic acid is at least about 0.01 wt% (e.g., at least about 0.05 wt%, at least about 0.1 wt%, at least about 0.25 wt%, at least about 0.5 wt%, at least about 0.75 wt%, or at least about 1 wt%) to at most about 5 wt% (e.g., at most about 4 wt%, at most about 3 wt%, at most about 2 wt%, or at most about 1 wt%) of the CMP composition in concentrated form or in diluted point-of-use (POU) slurry form. Without wishing to be bound by theory, it is believed that the aminophosphonic acid can further improve the performance of the CMP composition described herein (e.g., polysilicon removal rate, polysilicon to silicon nitride removal selectivity, or both).

[0050] In certain embodiments, the chemical mechanical polishing compositions described herein may further include one or more low health hazard salts, including zwitterions (e.g., classified as GHS category 3 or above). In certain embodiments, the salt may include a sulfonate group, an amino group, a carboxylate group, or a tetraalkylammonium group, wherein the salt containing the tetraalkylammonium group is different from the salt of tetramethylammonium hydroxide. Examples of salts that can be used for this purpose include, but are not limited to, various amino acids, such as glycine, taurine, choline hydroxide, and the like. In certain embodiments, the amount of the salt is at least about 0.05 wt % (e.g., at least about 0.1 wt %, at least about 0.2 wt %, at least about 0.3 wt %, at least about 0.4 wt %, at least about 0.5 wt %, at least about 0.6 wt %, at least about 0.7 wt %, at least about 0.8 wt %, at least about 0.9 wt %, or at least about 1 wt %) to at most about 5 wt % (e.g., at most about 4 wt %, at most about 3 wt %, at most about 2 wt %, at most about 1.9 wt %, at most about 1.8 wt %, at most about 1.7 wt %, at most about 1.6 wt %, at most about 1.5 wt %, at most about 1.4 wt %, at most about 1.3 wt %, at most about 1.2 wt %, at most about 1.1 wt %, or at most about 1 wt %) of the CMP composition described herein in a concentrate or diluted point-of-use (POU) slurry form. In certain embodiments, the salt concentration may be capped at 2X the concentration of the dilutable concentrate of the formulation. In some specific examples, the concentration of glycine can be about 0.75 wt % and the concentration of choline hydroxide can be about 0.5 wt %. Without wishing to be bound by theory, it is believed that the salt can further enhance the performance of the CMP compositions described herein (e.g., polysilicon removal rate, polysilicon to silicon nitride removal selectivity, or both).

[0051] Concentration capability (also referred to as "dilution capability") is one of the requirements set by semiconductor manufacturers for any modern chemical mechanical polishing composition in an effort to reduce the cost of ownership (COO) of manufacturing consumables. The chemical mechanical polishing composition described herein can be used as at least a 2X dilutable concentrated mixture. That is, the chemical mechanical polishing composition can be diluted at least 2 times (e.g., at least 3 times, at least 4 times, at least 5 times, or at least 10 times) before use by an end user. The chemical mechanical polishing composition of the present disclosure can include 0.05-20 weight percent (e.g., 2-3 weight percent) of abrasive in a 2X concentrated composition mixture.

[0052] Furthermore, in certain embodiments, the chemical mechanical polishing composition of the present disclosure can include one or more additives as optional components, such as a pH adjuster, a corrosion inhibitor, a surfactant, an organic solvent, and a defoaming agent.

[0053] In certain specific examples, the chemical mechanical polishing composition of the present disclosure includes at least one pH adjuster. The pH adjuster can bring the chemical mechanical polishing composition into the pH range during operation. A variety of alkaline pH adjusters expected to be used include, but are not limited to, potassium hydroxide, ammonium hydroxide, sodium hydroxide, cesium hydroxide, triethanolamine, tetrabutylammonium hydroxide, or any combination thereof.

[0054] In certain specific examples, the amount of water is at least about 50 wt% (e.g., at least about 55 wt%, at least about 60 wt%, at least about 65 wt%, at least about 70 wt%, at least about 75 wt%, at least about 80 wt%, at least about 85 wt%, at least about 90 wt%, at least about 95 wt%, or at least about 97 wt%) to at most about 99 wt% (e.g., at most about 95 wt%, at most about 90 wt%, at most about 85 wt%, at most about 75 wt%, at most about 70 wt%, at most about 65 wt%, at most about 60 wt%, or at most about 55 wt%) of the CMP composition in concentrated form or in diluted point-of-use (POU) slurry form.

[0055] In certain specific examples, the CMP composition of the present disclosure can have a pH value of at least about 7 (e.g., at least about 7.5, at least about 8, at least about 8.5, at least about 9, at least about 9.5, or at least about 10) to at most 12 (e.g., at most about 11.5, at most about 11, at most about 10.5, or at most about 10). Without wishing to be bound by theory, it is believed that a CMP composition not having the above pH value will not be able to achieve a high polysilicon removal rate, a high polysilicon to silicon nitride removal rate ratio, or both.

[0056] In certain specific examples, when the CMP composition of the present disclosure is diluted, at least one oxidizing agent can be added to the composition. Oxidizing agents expected to be used in the compositions of the present disclosure include, but are not limited to, hydrogen peroxide, ammonium persulfate, silver nitrate (AgNO 3 ), iron nitrate or iron chloride, peracids or their salts, ozone water, potassium ferricyanide, potassium dichromate, potassium iodate, potassium bromate, vanadium trioxide, hypochlorous acid, sodium hypochlorite, potassium hypochlorite, calcium hypochlorite, magnesium hypochlorite, iron nitrate, KMnO 4 , other inorganic or organic peroxides, or mixtures thereof. In certain specific examples, the oxidizing agent can be hydrogen peroxide. The oxidizing agent can be present in an amount of about 0.1 wt% to about 5 wt% (e.g., about 0.4 wt% to about 2 wt%) of the composition in concentrated form or in diluted point-of-use (POU) slurry form. In certain specific examples, the CMP compositions described herein can exclude the above oxidizing agents.

[0057] In certain specific instances, the CMP compositions of the present disclosure may exclude certain components, such as tetramethylammonium hydroxide or its salts, oxidizing agents (such as those described above), bicarbonates (e.g., potassium bicarbonate or ammonium bicarbonate), carbonates (e.g., guanidine carbonate), health - hazard chemicals classified as GHS category 1 or 2 (e.g., ethylenediamine, piperazine, 1,3 - diaminopropane, imidazole, 1,2,4 - triazole or 3 - amino - 1,2,4 - triazole), and / or compounds having a boiling point below 50 °C (e.g., propylamine or isopropylamine).

[0058] Generally, the CMP compositions of the present disclosure may have a relatively high polysilicon removal rate. In certain specific instances, the CMP compositions of the present disclosure may have a polysilicon removal rate of at least about 8,000 Å / min (e.g., at least about 8,500 Å / min, at least about 9,000 Å / min, at least about 9,500 Å / min, at least about 10,000 Å / min, at least about 10,500 Å / min, at least about 11,000 Å / min, at least about 11,500 Å / min or at least about 12,000 Å / min) to at most about 15,000 Å / min (e.g., at most about 14,000 Å / min or at most about 13,000 Å / min). As mentioned herein, this polysilicon removal rate is measured at a polishing down - pressure of 2.5 pounds per square inch.

[0059] Generally, the CMP compositions of the present disclosure may have a relatively high polysilicon - to - silicon nitride removal selectivity (e.g., a relatively high polysilicon - to - silicon nitride removal rate ratio). In certain specific instances, the CMP compositions of the present disclosure may have a polysilicon - to - silicon nitride removal rate ratio of at least about 50:1 (e.g., at least about 75:1, at least about 100:1, at least about 110:1, at least about 120:1, at least about 130:1, at least about 140:1, or at least about 150:1) to at most about 200:1 (e.g., at most about 180:1 or at most about 150:1). As mentioned herein, this polysilicon - to - silicon nitride removal rate ratio / selectivity is measured at a polishing down - pressure of 2.5 pounds per square inch.

[0060] Generally, the components of the CMP compositions described in the present disclosure (e.g., abrasives, compounds of structures (I) and (II), aminophosphonic acids, and additives) may be obtained from commercial sources or synthesized by methods known in the art.

[0061] In certain specific instances, the present disclosure features a method for polishing an exposed polysilicon film on the surface of a wafer substrate, including the step of treating the polysilicon film with the chemical - mechanical polishing composition described herein. This method may be carried out, for example, by the following steps:

[0062] A) Place the wafer in a polishing machine equipped with a polishing pad;

[0063] B) Contact the wafer with the polishing pad in the presence of the chemical - mechanical polishing composition described herein. In certain specific examples, the CMP composition can be diluted with DI water (e.g., at least 2 - fold, at least 3 - fold, at least 4 - fold, at least 5 - fold or at least 10 - fold) before treating or contacting the polysilicon film with the CMP composition. Other components and / or steps used in the above CMP method are described below or are known in the prior art.

[0064] The entire content of all publications (e.g., patents, patent - published applications, and papers) cited herein is incorporated herein by reference in its entirety.

[0065] The following examples are intended to further illustrate the subject matter of the present disclosure and should in no way be construed as limiting the present disclosure.

[0066] Embodiment

[0067] The chemical - mechanical polishing compositions in the following examples are prepared according to the description accompanying each example. The following polishing tests are performed using each chemical - mechanical polishing composition from the following examples to obtain polysilicon and silicon nitride removal rates.

[0068] Each uses an Applied Materials Mirra polishing machine equipped with a VISIONPAD TM 6000 polishing pad, with a down - pressure of 2.5 pounds per square inch, a chemical - mechanical polishing composition flow rate of 200 milliliters per minute, a platform rotation speed of 120 rpm, and a carrier head rotation speed of 114 rpm, to polish 200 - millimeter polysilicon and silicon nitride wafers for 60 seconds. The silicon and silicon nitride material removal rates are determined by subtracting the film thickness of the silicon or silicon nitride film on the coated wafer after polishing from the film thickness on the same coated wafer before polishing and dividing the difference by the polishing time. The film thickness value is the average of 29 film thickness measurements taken on the wafer using a Filmetrics F80C polarized - light ellipsometer instrument. The polysilicon - to - silicon nitride removal rate ratio of each chemical - mechanical polishing composition is determined by dividing the polysilicon removal rate obtained by polishing the corresponding coated wafer with the chemical - mechanical polishing composition under discussion by the silicon nitride removal rate.

[0069] Example 1

[0070] This example compares the polishing performance of comparative - example chemical - mechanical polishing compositions (i.e., C - 1A to C - 1D, Table 1.1) that may not contain the compound of structure (I) with the chemical - mechanical polishing compositions of the present disclosure (i.e., 1E, 1F, 1G, and 1H).

[0071] Each of the chemical mechanical polishing compositions C-1A to C-1D and 1E to 1H includes the amine compounds 1A to 1H listed in Table 1.1, 5-aminotetrazolyl monohydrate, aminotri(methanephosphonic acid), high-purity colloidal silica, and potassium hydroxide to adjust the pH of the mixture to a final value of 10.8. The polysilicon and silicon nitride removal rates of Table 1.2 were determined using the chemical mechanical polishing compositions C-1A to C-1D and 1E to 1H from Table 1.1 in polishing tests P-1A to P-1F (comparative examples) and P-1G and P-1H (the present disclosure). The test results are summarized in Table 1.2.

[0072] This example demonstrates the advantages of amines of structure (I) (1E, 1F, 1G, and 1H) where X is alkyl, hydroxy, or substituted hydroxy and Y is amino over other amine structures having structures different from structure (I).

[0073] For example, the results in Table 1.2 show that, in the chemical mechanical polishing compositions tested, the amines having structure (I) (wherein X is hydroxyethoxy, Y is amino and n=0, i.e., 2-(2-aminoethoxy)ethanol) and the azoles having structure (II) (wherein Z 1 =Z 2 =N,Z 3 For C and R 7 For NH 2 , i.e., 5-aminotetrazole) has the fourth highest polysilicon removal rate and the fifth highest polysilicon to silicon nitride removal rate ratio.

[0074] As another example, the results in Table 1.2 show that among the chemical mechanical polishing compositions tested, the chemical mechanical polishing composition 1G comprising an amine having structure (I) (wherein X is a hydroxyl group, Y is an amino group and n=0, i.e., monoethanolamine) and an azole having structure (II) (i.e., 5-aminotetrazolyl) has the third highest polysilicon removal rate and the fourth highest polysilicon to silicon nitride removal rate ratio.

[0075] The results in Table 1.2 also show that among the chemical mechanical polishing compositions tested, the chemical mechanical polishing composition 1H comprising an amine having structure (I) (wherein X is a hydroxyl group, Y is an amino group and n=1, i.e., 3-amino-1-propanol) and an azole having structure (II) (i.e., 5-aminotetrazolyl) has the highest polysilicon removal rate and the second highest polysilicon to silicon nitride removal rate ratio.

[0076] The results in Table 1.2 also show that in the chemical mechanical polishing composition tested in this particular example, the amine having structure (I) (wherein X is CH 3The chemical mechanical polishing composition 1E of an amine (wherein X is a hydroxyl group, Y is an amino group and n = 0, i.e., propylamine) and a 5-aminotetrazole of structure (II) has the second highest polysilicon removal rate and the highest polysilicon to silicon nitride removal rate ratio.

[0077] Based on the comparative example chemical mechanical polishing compositions of unfunctionalized amines exemplified by amine 1D (isopropylamine), such as C-1D, can produce a high polysilicon to silicon nitride removal rate ratio (polishing example P-1D, Table 1.2). However, the low boiling point and related toxicity and fire hazard of these amines make these amines unsuitable for chemical mechanical polishing composition applications.

[0078] In this example, the chemical mechanical polishing compositions including amine 1D (which has a very low boiling point) are only for comparison purposes. Once this amine is excluded, it is clear that the chemical mechanical polishing composition 1G based on the functionalized amine 1G of structure (I) (where X is a hydroxyl group, Y is an amino group and n = 0, i.e., monoethanolamine) exhibits a polysilicon removal rate at least 25% higher than the remaining comparative example chemical mechanical polishing composition examples in Table 1.2 and a polysilicon to silicon nitride removal rate ratio at least 26% higher than the remaining comparative example chemical mechanical polishing composition examples in Table 1.2. Similarly, the chemical mechanical polishing composition based on amine 1-H of structure (I) (where X is a hydroxyl group, Y is an amino group and n = 1, i.e., 3-amino-1-propanol) exhibits a polysilicon removal rate at least 38% higher than the comparative example chemical mechanical polishing composition examples in Table 1.2 and a polysilicon to silicon nitride removal rate ratio at least 47% higher than the comparative example chemical mechanical polishing composition examples in Table 1.2. Furthermore, the chemical mechanical polishing composition based on amine 1-F (i.e., 2-(2-aminoethoxy)ethanol) exhibits a polysilicon removal rate at least 16% higher than the comparative example chemical mechanical polishing composition examples in Table 1.2 and a polysilicon to silicon nitride removal rate ratio at least 8% higher than the comparative example chemical mechanical polishing composition examples in Table 1.2.

[0079] This example illustrates the advantage of certain functionalized amines of structure (I) over other types of amines in terms of improving the polysilicon removal rate when used in the corresponding chemical mechanical polishing compositions when combined with the 5-aminotetrazole of structure (II).

[0080] Table 1.1

[0081]

[0082] 1: Comp. = Composition

[0083] 2: Examples 1A - 1D are comparative examples, and examples 1E, 1F, 1G and 1H are examples of the present disclosure.

[0084] Table 1.2

[0085]

[0086] Example 2

[0087] This example shows the effect of the second amino group in the structure of the functionalized amine (I) (e.g., when both functional groups X and Y are amino groups) on the polysilicon removal rate and the polysilicon to silicon nitride selectivity.

[0088] Comparative example chemical mechanical polishing compositions C-2A to C-2C, the chemical mechanical polishing compositions 2D to 2G of the present disclosure, and the chemical mechanical polishing composition 1H of the present disclosure (included in this example for comparison) each include the corresponding amines, 5-aminotetrazole, aminotris(methylphosphonic acid), and high-purity colloidal silica shown in Table 2.1. Enough nitric acid or potassium hydroxide (KOH) was added to adjust the pH value of the mixture to a final value of 10.8.

[0089] Polysilicon and silicon nitride removal rate polishing tests P-2A to P-2G and polishing test P-1H were carried out using the chemical mechanical polishing compositions C-2A to C-2C, 2D to 2G, and polishing composition 1H from Table 2.1. The polishing rate and selectivity ratio results are summarized in Table 2.2.

[0090] This example shows that the less substituted diamines (amines 2D to 2G) of structure (I) in which both X and Y are amino groups exhibit a polysilicon removal rate that is at least 46% higher and a silicon to silicon nitride removal rate ratio that is at least 117% higher than that of the amine of structure (I) in which X is a hydroxyl group and Y is an amino group, i.e., amine 1H of the present disclosure. Furthermore, the highly substituted comparative example diamines C-2A to C-2C exhibit a polysilicon removal rate that is at least 46% lower than that of the unsubstituted amine of structure (I) in which X is a hydroxyl group and Y is an amino group, i.e., amine 1H of the present disclosure.

[0091] In Table 2.2, among all the comparative examples and the examples of the present disclosure, the chemical mechanical polishing composition 2D of the present disclosure based on the unsubstituted diamine 2D having structure (I) (where both X and Y are amino groups, i.e., ethylenediamine) exhibits the highest polysilicon removal rate.

[0092] Table 2.1

[0093]

[0094] *C1, C2, and C3 refer to three carbons between groups X and Y in structure (I).

[0095] Table 2.2

[0096]

[0097] Example 3

[0098] This example shows the synergistic effect of amine 1G of structure (I) (where X is a hydroxyl group and Y is an amino group (i.e., monoethanolamine)) and azole 1G' of structure (II) (where R 7 is an amino group, Z 1 is a nitrogen atom, Z 2 is a nitrogen atom and Z 3 is a carbon atom (i.e., 5-aminotetrazole)) on the polysilicon removal rate and the polysilicon-to-silicon nitride removal rate selectivity ratio observed in polishing example P-1G, as shown in Table 3.1.

[0099] This synergistic effect is evident when the results of polishing examples P-3A and P-3B are compared with the results of polishing example P-1G (included in Table 3.1 for comparison and based on composition 1G).

[0100] Referring to Table 3.1, comparative chemical mechanical polishing compositions C-3A and C-3B and the chemical mechanical polishing composition 1G of the present disclosure each contain aminotris(methylphosphonic acid), high-purity colloidal silica, and sufficient KOH to adjust the pH value of the mixture to a final value of 10.8. In addition, as can be seen in Table 3.1, composition C-3A contains amine 1G (1-aminoethanol), but does not contain any azole compounds; composition C-3B contains azole (5-aminotetrazole), but does not contain any amine compounds; composition 1G contains both amine 1G (1-aminoethanol) and azole (5-aminotetrazole monohydrate). The conductivity of compositions C-3A and C-3B is similar to that of composition 1G. Polysilicon and silicon nitride polishing tests P-3A, P-3B, and P-1G in Table 3.1 were performed using compositions C-3A, C-3B, and 1G. The results of the polishing tests are summarized in Table 3.1.

[0101] This example shows that omission of either amine 1G (1-aminoethanol) or azole (5-aminotetrazole) from the chemical mechanical composition components (compositions C-3B and C-3A, respectively) results in a loss of polysilicon removal rate when the composition is used in polishing examples (polishing examples P-3B and P-3A, respectively), even though the ionic strength / conductivity of the composition is similar to that of the polishing composition 1G containing both components.

[0102] Although the mechanism of the unexpected synergistic interaction between the amine and the azole is not clear, it is apparent that the polysilicon removal rate and the polysilicon to silicon nitride removal rate selectivity values obtained from the composition 1G containing amine 1G and azole are at least 34% and 15% higher, respectively, than the highest corresponding values of the polysilicon removal rate and the polysilicon to silicon nitride removal rate selectivity obtained from the compositions C-3A and C-3B in which one of the two components is omitted (see P-3A and P-3B) (Table 3.1).

[0103] Table 3.1

[0104]

[0105] Example 4

[0106] This example demonstrates the effect of various azole structures (4A' to 4F', Table 4.1) on the polysilicon removal rate and the polysilicon to silicon nitride removal rate ratio (Table 4.2) observed in polishing examples P-4A to P-4F when a combination of an azole and amine 1-G (2-aminoethanol) is used in a chemical mechanical polishing composition.

[0107] Furthermore, this example demonstrates the advantages of using an azole / azole derivative of Structure II (as listed in Table 4.1), in which Structure II, R 7 is H, COOH, C 1 -C 3 alkyl or N(R 9 ) 2 , each R 9 is independently H or C 1 -C 3 alkyl, with the proviso that when Z 3 is -N-, R 7 is deleted. As can be seen in Table 4.1, the group corresponding to R 7 in azole 4A' is phenyl. In this regard, azole 4A' is not a compound of Structure (II). Surprisingly, azole 4A' shows a lower polysilicon removal rate and a lower polysilicon to silicon nitride removal rate ratio than azoles 4B'-4F' which are compounds of Structure (II) (see Table 4.2).

[0108] The polishing composition was prepared in a manner similar to the other examples. Similarly, polysilicon and silicon nitride polishing tests were conducted in polishing examples P-4A to P-4F, and the polishing test results of Example P-1G (from Table 1.2) were included in Table 4.2 for comparison.

[0109] The polishing results summarized in Table 4.2 clearly show the advantages of using a combination of a compound having structure (I) and an azole / azole derivative having structure (II). The synergistic effect of these compounds on increasing the P-Si removal rate and the P-Si to SiN selectivity can be clearly seen in Table 4.2. As can be seen in Table 4.2, Comparative Example P-4A has the lowest P-Si removal rate and the lowest P-Si to SiN selectivity. All examples of the present disclosure (P-4B to P-4F and P-1G) have higher P-Si removal rates and P-Si to SiN removal rate ratios. In fact, Composition P-4C, which includes azole 4C (1,2,4-triazole), has a P-Si removal rate 40% higher than that of Comparative Example P-1A. Furthermore, Composition P-4B, which includes azole 4B' (imidazole), has a P-Si to SiN removal rate ratio 70% higher than that of Comparative Example P-1A.

[0110] Table 4.1

[0111]

[0112] Table 4.2

[0113]

[0114] Example 5

[0115] This example demonstrates the effect of additional components on the polysilicon removal rate and the polysilicon to silicon nitride removal rate ratio in a polishing composition closely related to Composition 1G of the present disclosure (Table 5.1). This example shows that additives such as taurine and choline hydroxide can substantially increase the polysilicon removal rate (as shown in polishing examples P-5A and P-5B, respectively). In addition, choline hydroxide (5B) significantly increases the polysilicon to silicon nitride removal rate ratio (as shown in polishing example P-5B).

[0116] The present disclosure's chemical mechanical polishing compositions 5A, 5B, and 1G listed in Table 5.1 each include amine 1-G (monoethanolamine), azole (5-aminotetrazole), aminotris(methylphosphonic acid), high-purity colloidal silica, and sufficient KOH or nitric acid to adjust the pH value of the mixture to a final value of 10.8. In addition, Composition 5A includes taurine and Composition 5B includes choline hydroxide. Polishing tests P-5A, P-5B, and P-1G were conducted according to the above standard protocol. The results are summarized in Table 5.1.

[0117] This example shows that the disclosed polishing composition 5A including taurine provides at least a 3% increase in polysilicon removal rate compared to the disclosed composition 1G (without any additional components); when these compositions are used in polishing tests P-5A and P-1G respectively, comparable polysilicon to silicon nitride removal rate ratios are provided. This example also shows that when these compositions are used in polishing tests P-5B and P-1G respectively, the disclosed polishing composition 5B including choline hydroxide provides at least a 25% increase in polysilicon removal rate and a 370% increase in polysilicon to silicon nitride removal rate ratio compared to the disclosed composition 1G (without any additional components).

[0118] In addition, Table 5.1 shows a summary of the colloidal stability data collected on the disclosed compositions 5A, 5B, and 1G prepared as 2X concentrates and subjected to accelerated aging conditions (60 °C oven, 3 weeks). If, at the end of the test cycle, the growth of the mean particle size (MPS) measured by dynamic light scattering (DLS) is <5 nm, the slurry is classified as "stable"; if the measured value of MPS growth is >5 nm, it is "unstable". MPS can be measured using a DLS tool such as the Malvern Zetasizer from Malvern Instruments. The colloidal stability test results show that the 2X concentrates of the disclosed composition 1G (without additional components) and the disclosed compositions 5A and 5B were all found to be stable.

[0119] Table 5.1

[0120]

[0121] Although the present disclosure has been described with respect to the embodiments presented herein, it should be understood that other modifications and variations are possible without departing from the spirit and scope of the present disclosure as defined in the appended claims.

Claims

1. A chemical mechanical polishing composition, comprising: 1) at least one abrasive; 2) at least one compound of structure (I): wherein, the compound of structure (I) is an amino alcohol selected from the group consisting of monoethanolamine, diethanolamine, 1-amino-2-propanol, 1-amino-2-butanol, 1,3-diamino-2-propanol, 3-amino-1,2-propanediol, 3-amino-1-propanol, 2-(2-aminoethoxy)ethanol, 2-amino-3-methyl-1-butanol, and 5-amino-1-pentanol; or, the compound of structure (I) is a diamine selected from the group consisting of 2,2-dimethyl-1,3-propanediamine, 1,3-diaminopentane, and 2-(3-aminopropylamine)ethanol; 3) at least one compound of structure (II): wherein: Z 1 and Z 2 each independently is -CR 8 - or -N-, where R 8 is H, N(R b ) 2 , COOH, C 1 -C 3 alkyl, each R b independently is H or C 1 -C 3 alkyl; or Z 1 and Z 2 together form a 5-6 membered ring fused to the 5-membered ring in structure (II); Z 3 is -C- or -N-; and R 7 is H, COOH, C 1 -C 3 alkyl or N(R 9 ) 2 , wherein each R 9 is independently H or C 1 -C 3 alkyl, with the proviso that when Z 3 is -N-, R 7 is deleted; 4) at least one tetraalkylammonium salt, the at least one tetraalkylammonium salt being different from the salt of tetramethylammonium hydroxide; and 5) water; wherein the composition has a pH of at least 10, wherein the composition does not include tetramethylammonium hydroxide or its salt, and the composition has a polysilicon to silicon nitride removal rate ratio of at least 100:1; wherein the composition does not include an oxidizing agent and ethylenediamine.

2. The composition according to claim 1, wherein, the composition has a polysilicon to silicon nitride removal rate ratio of at most 200:

1.

3. The composition according to claim 1, wherein, the composition has a polysilicon removal rate of at least 8000 Å / min.

4. The composition according to claim 1, wherein, the amount of the compound of structure (I) is 0.1 wt% to 15 wt% of the composition.

5. The composition according to claim 1, wherein, the compound of structure (II) is imidazole or triazole.

6. The composition according to claim 5, wherein, the compound of structure (II) is selected from the group consisting of imidazole, 1,2,4-triazole, 3-amino-1,2,4-triazole, benzotriazole, 3,5-diamino-1,2,4-triazole, and 1,2,4-triazole-3-carboxylic acid.

7. The composition according to claim 1, wherein, the compound of structure (II) is tetrazole.

8. The composition according to claim 7, wherein, the compound of structure (II) is 5-(aminomethyl)tetrazole, 5-methyl-1H-tetrazole, 5-aminotetrazole, or a hydrate thereof.

9. The composition according to claim 1, wherein, the amount of the compound of structure (II) is 0.1 wt% to 15 wt% of the composition.

10. The composition according to claim 1, wherein, the abrasive is selected from the group consisting of alumina, calcined silica, colloidal silica, coated particles, titanium dioxide, cerium dioxide, zirconium oxide, and any combination thereof.

11. The composition according to claim 1, wherein, the abrasive is colloidal silica.

12. The composition according to claim 1, wherein, the amount of the abrasive is 0.05 wt% to 20 wt% of the composition.

13. The composition according to claim 1, Among them, the amount of the tetraalkylammonium salt is 0.05% to 5% by weight of the composition.

14. The composition according to claim 1, further comprising an amino acid.

15. The composition according to claim 14, wherein, the amount of the amino acid is 0.05% to 5% by weight of the composition.

16. The composition according to claim 1, further comprising an aminophosphonic acid.

17. The composition according to claim 16, wherein, the aminophosphonic acid is aminotris(methylenephosphonic acid).

18. The composition according to claim 16, wherein, the amount of the aminophosphonic acid is 0.01% to 5% by weight of the composition.

19. The composition according to claim 1, further comprising a pH regulator.

20. The composition according to claim 1, wherein, the composition has a pH of 10 to 12.

21. The composition according to claim 1, wherein, the composition does not include bicarbonate.

22. A chemical mechanical polishing composition comprising: 1) at least one abrasive; 2) at least one compound of structure (I): wherein: the compound of structure (I) is an amino alcohol selected from the group consisting of monoethanolamine, diethanolamine, 1-amino-2-propanol, 1-amino-2-butanol, 1,3-diamino-2-propanol, 3-amino-1,2-propanediol, 3-amino-1-propanol, 2-(2-aminoethoxy)ethanol, 2-amino-3-methyl-1-butanol, and 5-amino-1-pentanol; or, the compound of structure (I) is a diamine selected from the group consisting of 2,2-dimethyl-1,3-propanediamine, 1,3-diaminopentane, and 2-(3-aminopropylamine)ethanol; 3) at least one compound of structure (II): wherein: Z 1 and Z 2 each independently is -CR 8 - or -N-, wherein R 8 is H, N(R b ) 2 , COOH, C 1 -C 3 alkyl, each R b independently is H or C 1 -C 3 alkyl; or Z 1 and Z 2 together form a 5-6 membered ring fused to the 5-membered ring in structure (II); Z 3 is -C- or -N-; and R 7 is H, COOH, C 1 -C 3 alkyl or N(R 9 ) 2 , where each R 9 is independently H or C 1 -C 3 alkyl, with the proviso that when Z 3 is -N-, R 7 is deleted; and 4) at least one amino acid; and 5) water; wherein the composition has a pH of at least 10, wherein the composition does not include tetramethylammonium hydroxide or its salt, and the composition has a polysilicon to silicon nitride removal rate ratio of at least 100:1; wherein the composition does not include an oxidizing agent and ethylenediamine.

23. The composition according to claim 22, wherein, the composition has a polysilicon to silicon nitride removal rate ratio of at most 200:

1.

24. The composition according to claim 22, wherein, the composition has a polysilicon removal rate of at least 8000 Å / min.

25. The composition according to claim 22, wherein, the amount of the compound of structure (I) is 0.1% to 15% by weight of the composition.

26. The composition according to claim 22, wherein, the compound of structure (II) is imidazole or triazole.

27. The composition according to claim 26, wherein, the compound of structure (II) is selected from the group consisting of imidazole, 1,2,4-triazole, 3-amino-1,2,4-triazole, benzotriazole, 3,5-diamino-1,2,4-triazole, and 1,2,4-triazole-3-carboxylic acid.

28. The composition according to claim 22, wherein, the compound of structure (II) is tetrazole.

29. The composition according to claim 28, wherein, the compound of structure (II) is 5-(aminomethyl)tetrazole, 5-methyl-1H-tetrazole, 5-aminotetrazole or a hydrate thereof.

30. The composition according to claim 22, wherein, the amount of the compound of structure (II) is 0.1% to 15% by weight of the composition.

31. The composition according to claim 22, wherein, the abrasive is selected from the group consisting of alumina, calcined silica, colloidal silica, coated particles, titanium dioxide, cerium dioxide, zirconium oxide and any combination thereof.

32. The composition according to claim 22, wherein, the abrasive is colloidal silica.

33. The composition according to claim 22, wherein, the amount of the abrasive is 0.05% to 20% by weight of the composition.

34. The composition according to claim 22, wherein, the amount of the amino acid is 0.05% to 5% by weight of the composition.

35. The composition according to claim 22, further comprising a tetraalkylammonium salt, wherein, the tetraalkylammonium salt is different from the salt of tetramethylammonium hydroxide.

36. The composition according to claim 35, wherein, the amount of the tetraalkylammonium salt is 0.05% to 5% by weight of the composition.

37. The composition according to claim 22, further comprising an aminophosphonic acid.

38. The composition according to claim 37, wherein, the aminophosphonic acid is aminotris(methylenephosphonic acid).

39. The composition according to claim 37, wherein, the amount of the aminophosphonic acid is 0.01% to 5% by weight of the composition.

40. The composition according to claim 22, further comprising a pH regulator.

41. The composition according to claim 22, wherein, the composition has a pH of 10 to 12.

42. The composition according to claim 22, wherein, the composition does not include bicarbonate.

43. A method for polishing an exposed polysilicon film on the surface of a wafer substrate, comprising treating the polysilicon film with the composition according to any one of claims 1-42.

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