Dicationic polymers and copolymers and their use for chemical mechanical planarization

Abstract

The synthesis of a dicationic polymer or copolymer is disclosed. The dicationic polymer or copolymer is formed from at least one dicationic (or dicationic) monomer. A chemical mechanical planarization (CMP) slurry includes an abrasive, an activator, an oxidizer, an additive including a dicationic polymer or copolymer, and water. The use of the synthesized dicationic polymer or copolymer in the CMP slurry reduces dishing and erosion in highly selective tungsten slurries.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 387,137, filed December 13, 2022, which is incorporated herein by reference.

[0002] This disclosure relates to chemical mechanical planarization or polishing ("CMP") slurries (or compositions or formulations), polishing methods, and polishing systems for performing chemical mechanical planarization in the manufacture of semiconductor devices. In particular, this disclosure relates to polishing slurries suitable for use in polishing patterned semiconductor wafers that include tungsten-containing metallic materials. [Background technology]

[0003] Chemical mechanical polishing or planarization (CMP) has been used successfully in integrated circuit manufacturing processes for decades and is considered a key and enabling technology for the demands of miniaturization.

[0004] Integrated circuits are interconnected using known multilevel interconnects. The interconnect structure typically includes a first level of metallization, an interconnect layer, a second level of metallization, and typically a third and subsequent levels of metallization. Interlayer dielectric materials, such as silicon dioxide and sometimes low-k materials, are used to electrically isolate different levels of metallization within a silicon substrate or well. Electrical connections between different interconnect levels are made through the use of metallized vias, particularly tungsten vias. U.S. Patent No. 4,789,648 describes a method for fabricating multiple metallized layers and vias in an insulating film. In a similar manner, metal contacts are used to form electrical connections between interconnect levels and devices formed within wells. Metal vias and contacts are typically filled with tungsten, and adhesion layers, such as titanium nitride (TiN) and / or titanium, are typically used to adhere metal layers, such as tungsten metal layers, to the dielectric material.

[0005] In one semiconductor manufacturing process, metallized vias or contacts are formed by blanket tungsten deposition followed by a CMP step. In a typical process, a via hole is etched through an interlayer dielectric (ILD) to an interconnect line or semiconductor substrate. Next, a thin adhesion layer, typically titanium nitride and / or titanium, is formed on the ILD and introduced into the etched via hole. A tungsten film is then blanket deposited on the adhesion layer and into the via. Deposition continues until the via hole is filled with tungsten. Finally, excess tungsten is removed by CMP to form the metal via.

[0006] In another semiconductor manufacturing process, tungsten is used as a gate electrode material in transistors because it has better electrical properties than polysilicon, which has traditionally been used as a gate electrode material, as taught by A. Yagishita et al., IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 47, NO. 5, MAY 2000.

[0007] In a typical CMP process, a substrate is placed in direct contact with a rotating polishing pad. A carrier applies pressure to the backside of the substrate. During the polishing process, the pad and table are rotated while simultaneously maintaining a downward force on the backside of the substrate. An abrasive, chemically reactive solution, commonly referred to as a polishing "slurry," "composition," or "formulation," is placed on the pad during polishing. The rotation and / or movement of the pad relative to the wafer forces the slurry into the space between the polishing pad and the substrate surface. The slurry initiates the polishing process by chemically reacting with the film being polished. The polishing process is driven by the rotational motion of the pad relative to the substrate as the slurry is delivered to the wafer / pad interface. Polishing continues in this manner until the desired film on the insulator is removed. It is believed that tungsten removal in CMP is due to the combined effects of mechanical wear and tungsten oxidation and subsequent dissolution.

[0008] Although seemingly relatively simple, chemical mechanical planarization (CMP) is a highly complex process, as noted by Lee Cook in Digital Encyclopedia of Applied Physics, 2019, DOI:10.1002 / 3527600434.eap847 10.1002 / 3527600434.eap847, and in most cases, CMP technology is evolving faster than the underlying understanding, as noted by Seo, J. in Journal of Materials Research 2021, 36 (1), 235.1.

[0009] Its importance as a technology that realizes past and future demands for device miniaturization and new trends in the semiconductor industry is clear. Various interactions between the wafer, slurry, and pad, as well as general process parameters, determine the results of CMP. Finally, material removal in CMP is the result of a complex interplay between chemical and mechanical forces, as described in Lee, D.; Lee, H.; Jeong, H. Slurry components in metal chemical mechanical planarization (CMP) process: A review. International Journal of Precision Engineering and Manufacturing 2016, 17, 1751. A large number of materials are used in semiconductor device fabrication, all of which require optimized CMP processes. Simultaneous polishing of a combination of disparate materials, such as dielectric materials, barrier layers, and metal layers, presents a real challenge for CMP.

[0010] One of the problems commonly encountered in CMP, especially for metal applications such as tungsten, is how to control topological defects such as erosion and dishing. Smaller feature sizes and devices at the 7 nm node and beyond are imposing even more stringent requirements on defect tolerance during polishing.

[0011] Highly selective slurries with a large difference in metal removal rate versus dielectric removal rate are of great interest for future industrial needs. However, the use of such highly selective slurries does not come without drawbacks. Metal layers can easily be over-polished, resulting in a "dishing" effect. Another unacceptable defect is called "erosion," which refers to the topographical difference between areas of dielectric and dense arrays of metal vias or trenches.

[0012] Specially designed aqueous slurries are considered a major driving force in improving CMP performance for future devices. Slurry development not only affects the removal rate and selectivity between different layers, but also controls defects during the polishing process. Generally, slurry compositions are complex combinations of abrasives and chemical ingredients with different functions. Polymer additives, such as dispersants, passivators, or generally topography-controlling additives, play an important role in slurry development by interacting with certain materials to achieve the desired removal rate, selectivity, and minimize surface defects. For example, positively charged polymers can be used to inhibit tungsten removal and reduce the dishing effect in tungsten CMP processes.

[0013] U.S. Pat. No. 5,876,490 describes the use of a polishing slurry containing abrasive particles, exhibiting a normal stress effect, and further containing a polyelectrolyte having ionic moieties of a different charge than the charge associated with the abrasive particles, wherein the concentration of the polyelectrolyte is about 5 to about 50% by weight of the abrasive particles, and the polyelectrolyte has a molecular weight of about 500 to about 10,000.

[0014] U.S. Pat. No. 6,776,810 describes a chemical-mechanical polishing system including (a) an abrasive, (b) a liquid carrier, and (c) a positively charged polyelectrolyte having a molecular weight of about 15,000 or more, and a method for polishing a substrate using the polishing system, wherein the abrasive includes particles that are electrostatically associated with the positively charged electrolyte.

[0015] U.S. Patent No. 7,247,567 provides a method for chemical mechanical polishing of a tungsten-containing substrate by using a composition comprising a tungsten etchant, a tungsten etching inhibitor, and water, wherein the tungsten polishing inhibitor is a polymer, copolymer, or polymer blend comprising at least one nitrogen-containing heterocyclic ring or at least one repeating group comprising a tertiary or quaternary nitrogen atom. This invention also provides a chemical mechanical polishing composition that is particularly useful for polishing tungsten-containing substrates.

[0016] U.S. Patent Application Publication No. 2010075501 describes an aqueous chemical mechanical polishing dispersion used to polish a polishing target including a tungsten-containing interconnect layer. The aqueous chemical mechanical polishing dispersion contains (A) a cationic water-soluble polymer, (B) an iron(III) compound, and (C) colloidal silica particles. The content (M A ) (mass%) and the content of iron (III) compound (B) (M B ) (mass%) is "M A / M B =0.004 to 0.1”. The pH of the chemical mechanical polishing aqueous dispersion is 1 to 3.

[0017] U.S. Patent Application Publication No. 2010 / 0252774(A1) describes a chemical mechanical polishing aqueous dispersion used for polishing a polishing target including a wiring layer containing tungsten. This chemical mechanical polishing aqueous dispersion contains (A) a cationic water-soluble polymer, (B) an iron(III) compound, and (C) colloidal silica having an average particle size of 10 to 60 nm calculated from the specific surface area determined by the BET method. The content (MA ) (mass%) and the content of colloidal silica (C) (M C ) (mass%) is "M A / M C =0.0001 to 0.003. Chemical mechanical polishing aqueous dispersion.

[0018] U.S. Patent No. 10,604,678 (B1) discloses a process and composition for polishing tungsten, which contains a low concentration of a selected quaternary phosphonium compound to at least reduce the corrosion rate of tungsten. The process and composition include providing a tungsten-containing substrate, providing a stable polishing composition containing as initial components water, an oxidizing agent, a selected quaternary phosphonium compound at a low concentration to at least reduce the corrosion rate, a dicarboxylic acid, an iron ion source, a colloidal silica abrasive, and optionally a pH adjuster, providing a chemical mechanical polishing pad having a polishing surface, creating dynamic contact at the interface between the polishing pad and the substrate, and supplying the polishing composition onto the polishing surface at or near the interface between the polishing pad and the substrate, whereby a portion of the tungsten is polished away from the substrate and the corrosion rate of the tungsten is reduced.

[0019] U.S. Patent Application Publication No. 2009 / 0081871 discloses a method comprising chemically mechanically polishing a substrate with an inventive polishing composition comprising a liquid carrier, a cationic polymer, an acid, and abrasive particles treated with an aminosilane compound.

[0020] U.S. Patent Application Publication No. 2014 / 0248823 describes a chemical-mechanical polishing composition containing (a) abrasive particles, (b) a polymer, and (c) water, wherein (i) the polymer has an overall charge, (ii) the abrasive particles have a zeta-potential Za measured in the absence of the polymer, and the abrasive particles have a zeta-potential Zb measured in the presence of the polymer, where the zeta-potential Za has the same sign as the overall charge of the polymer, and (iii) |Zeta-potential Zb|>|Zeta-potential Za|. This invention also provides a method for polishing a substrate using the polishing composition.

[0021] WO 9905706 describes chemical-mechanical polishing compositions and slurries that include a composition capable of etching tungsten and at least one inhibitor of tungsten etching, and methods of using the compositions and slurries to polish tungsten-containing substrates.

[0022] U.S. Patent Application Publication No. 20150259573 describes a chemical mechanical polishing composition for polishing a substrate having a tungsten layer, which comprises an aqueous liquid carrier, a colloidal silica abrasive dispersed in the liquid carrier and having a permanent positive charge of at least 6 mV, and a polycationic amine compound dissolved in the liquid carrier. A method for chemical mechanical polishing a substrate having a tungsten layer includes contacting the substrate with the polishing composition, moving the polishing composition relative to the substrate, and abrading the substrate to remove a portion of the tungsten from the substrate, thereby polishing the substrate.

[0023] Imidazolium-type cationic polymers, polyionic liquids based on phosphonium groups, and triazole- or triazolium-based polymers have been identified and used in CMP slurries in WO 2022 / 246381, WO 2022 / 261614, and WO 2023 / 056324, respectively, which are incorporated herein by reference in their entireties.

[0024] One of the problems commonly encountered in CMP, especially in metal applications such as tungsten, is dishing of tungsten lines and erosion of arrays of metal lines. Dishing and erosion are critical CMP parameters that determine the planarity of the polished wafer. Line dishing is typically greater for wider lines. Array erosion typically increases with increasing pattern density.

[0025] Tungsten CMP slurries must be formulated to minimize dishing and erosion in order to meet certain design goals that are critical to device functionality.

[0026] Finding solutions to control topological defects such as erosion and dishing is key to future CMP requirements. There remains a need for new tungsten CMP slurries that can reduce dishing and erosion while maintaining desirable removal rates during polishing. Summary of the Invention

[0027] The present invention fulfills the above-mentioned need by providing a highly engineered tungsten CMP slurry, system, and method of using the CMP slurry to minimize the noted problems of dishing and erosion in highly selective tungsten slurries while maintaining desirable polishing of metal layers, particularly tungsten films.

[0028] More particularly, the present invention discloses the synthesis of dicationic or dicationic polymers or copolymers.

[0029] The dicationic polymer or copolymer is formed by at least one first dicationic monomer. CMP slurries using the dicationic polymer have been demonstrated to reduce dishing and erosion and provide high selectivity in tungsten removal rate relative to TEOS or SiN.

[0030] Additionally, some specific aspects of the present invention are outlined below. Aspect 1: A dicationic polymer or copolymer formed by at least one dicationic monomer having the structure (I): [ka] During the ceremony, P1 represents a polymerizable group, Sp1 and Sp2 each independently represent a spacer group or a single bond; R1, R2, and R3 are each independently H or a substituted or unsubstituted aliphatic aromatic moiety selected from the group consisting of: (1) alkyl having less than 12 C atoms, less than 6 C atoms, less than 4 C atoms, or less than 2 C atoms, preferentially CH3 or CH2-CH3; and (2) phenyl, pyridinyl, pyrimidyl, furanyl, or any nitrogen-containing 5-membered ring, preferentially pyridinyl or pyrimidyl; and (3) a combination of (1) and (2). Cat denotes, at each occurrence, a cationic group, preferentially a cationic group of ammonium, guanidinium, triazolium, phosphonium, pyridinium or triazolium type. X - means an anionic counterion. Embodiment 2: A dicationic polymer or copolymer according to embodiment 1, wherein the polymerizable group P1 is chosen from groups containing a C=C double bond. Embodiment 3: The dicationic polymer or copolymer of embodiments 1-2, wherein the anionic counterion is selected from the group consisting of halide (F, Cl, Br, I), BF, PF, carboxylate, malonate, citrate, carbonate, fumarate, MeOSO, MeSO, CF, COO, CF, SO, nitrate, or sulfate. Aspect 4: The dicationic polymer or copolymer of any one of aspects 1-3, wherein the dicationic polymer or copolymer is formed by a polymerization method selected from the group consisting of free radical polymerization, reversible addition-fragmentation chain transfer polymerization (RAFT), nitroxide-mediated polymerization (NMP), atom transfer reaction polymerization (ATRP), ring-opening polymerization (ROMP), or polycondensation reaction. Embodiment 5: The dicationic polymer or copolymer of any one of embodiments 1-4, wherein the dicationic polymer or copolymer has block-copolymer properties. Aspect 6: A chemical mechanical planarization composition comprising the dicationic polymer or copolymer of any one of Aspects 1-5. Embodiment 7: A chemical mechanical planarization composition comprising: an abrasive selected from the group consisting of inorganic oxide particles, metal oxide-coated inorganic oxide particles, organic polymer particles, metal oxide-coated organic polymer particles, and combinations thereof; activator; oxidizing agents; A dicationic polymer or copolymer according to any one of aspects 1 to 5; water; and, optionally, corrosion inhibitors; dishing reducer; stabilizers; pH adjuster, 1. A chemical mechanical planarization composition comprising: Aspect 8: A system for chemical mechanical planarization, comprising: a semiconductor substrate having at least one surface containing tungsten; abrasive pads; and The chemical mechanical planarization composition according to any one of embodiments 6-7. wherein at least one surface containing tungsten is in contact with a polishing pad and a chemical mechanical planarization composition. system. Aspect 9: A polishing method for chemical mechanical planarization of a semiconductor substrate having at least one surface containing tungsten, comprising: a) contacting at least one surface containing tungsten with a polishing pad; b) providing a chemical mechanical planarization composition according to any one of embodiments 6-7; c) polishing at least one tungsten-containing surface with a chemical mechanical planarization composition; A polishing method comprising:

[0031] Abrasives include, but are not limited to, inorganic oxide particles, metal oxide coated inorganic oxide particles, organic polymer particles, metal oxide coated organic polymer particles, and combinations thereof.

[0032] Inorganic oxide particles include, but are not limited to, ceria, colloidal silica, high purity colloidal silica, fumed silica, colloidal ceria, alumina, titania, and zirconia particles.

[0033] Metal oxide coated inorganic oxide particles include, but are not limited to, ceria coated inorganic oxide particles such as ceria coated colloidal silica, ceria coated high purity colloidal silica, ceria coated alumina, ceria coated titania, ceria coated zirconia, or any other ceria coated inorganic oxide particles.

[0034] Organic polymer particles include, but are not limited to, polystyrene particles, polyurethane particles, polyacrylate particles, or any other organic polymer particles.

[0035] The metal oxide coated organic polymer particles are selected from the group consisting of ceria coated organic polymer particles and zirconia coated organic polymer particles.

[0036] The concentration of the abrasive may range from 0.01% to 30% by weight, preferably from about 0.05% to about 20% by weight, more preferably from about 0.01 to about 10% by weight, and most preferably from 0.1% to 2% by weight. Weight percentages are based on the composition.

[0037] Activators include, but are not limited to, (1) inorganic oxide particles coated with a transition metal selected from the group consisting of Fe, Cu, Mn, Co, Ce, and combinations thereof; (2) soluble catalysts selected from the group consisting of iron(III) nitrate, ammonium iron(III) oxalate trihydrate, iron(III) citrate tribasic monohydrate, iron(III) acetylacetonate, and the hydrated iron(III) sodium salt of ethylenediaminetetraacetic acid; and (3) metal compounds having multiple oxidation states selected from the group consisting of Ag, Co, Cr, Cu, Fe, Mo, Mn, Nb, Ni, Os, Pd, Ru, Sn, Ti, and V, and combinations thereof.

[0038] The activator is in the range of 0.00001% to 5.0% by weight, 0.0001% to 2.0% by weight, 0.0005% to 1.0% by weight, or 0.001% to 0.5% by weight.

[0039] Oxidizing agents include, but are not limited to, peroxy compounds selected from the group consisting of hydrogen peroxide, urea peroxide, performic acid, peracetic acid, propane peroxoacid, substituted or unsubstituted butane peroxoacid, hydroperoxy-acetaldehyde, potassium periodate, and ammonium peroxymonosulfate; and non-peroxy compounds selected from the group consisting of ferric nitrite, KClO, KBrO, and KMnO.

[0040] The oxidizer concentration may range from about 0.01% to 30% by weight, with a preferred concentration of oxidizer being from about 0.1% to 20% by weight and a more preferred concentration of oxidizer being from about 0.5% to about 10% by weight. Weight percentages are based on the composition.

[0041] Examples of dicationic polymers or copolymers include, but are not limited to, poly(3-ethyl-1-(3-(1-vinyl-1h-imidazol-3-ium-3-yl)propyl)-1h-imidazol-3-ium dibromide), poly(3-(tributylphosphino)propyl)-1-vinyl-1h-imidazol-3-ium dibromide), poly(3-(2-(trimethylammonio)ethyl)-1-vinyl-1h-imidazol-3-ium dibromide), and poly(3-(2-(trimethylammonio)ethyl)-1-vinyl-1h-imidazol-3-ium-co-n-vinyl-pyrrolidone dibromide).

[0042] Typical amounts of additives including dicationic polymers or copolymers are in the range of 0.00001 wt % to 1 wt %, 0.0001 wt % to 0.5 wt %, 0.0005 wt % to 0.1 wt %, or 0.001 wt % to 0.06 wt %.

[0043] Suitable pH adjusters for lowering the pH of the polishing composition include, but are not limited to, nitric acid, sulfuric acid, tartaric acid, succinic acid, citric acid, malic acid, malonic acid, various fatty acids, various polycarboxylic acids, and mixtures thereof. Suitable pH adjusters for raising the pH of the polishing composition include, but are not limited to, potassium hydroxide, sodium hydroxide, ammonia, tetraethylammonium hydroxide, ethylenediamine, piperazine, polyethyleneimine, modified polyethyleneimine, and mixtures thereof.

[0044] The pH of the slurry is 1-14, preferably 1-7, more preferably 1-6, and most preferably 1.5-4.

[0045] The CMP slurry may further include surfactants, dispersants, chelating agents, film-forming corrosion inhibitors, and biocides.

[0046] Other aspects, features, and embodiments of the present invention will become more fully apparent from the ensuing disclosure and appended claims.

[0047] The embodiments of the present invention may be used alone or in combination with each other. DETAILED DESCRIPTION OF THE INVENTION

[0048] The present invention fulfills the above-mentioned need by providing a highly engineered tungsten CMP slurry, system, and method of using the CMP slurry to reduce the noted problems of dishing and erosion in highly selective slurries while maintaining desirable polishing of metal layers, particularly tungsten films.

[0049] To reduce defects while enabling the desired removal rate and selectivity, specific water-soluble cationic polymers have been used in tailored slurry formulations.

[0050] The present invention extends the general applicability of cationic polymers to dicationic polymers or copolymers, which surprisingly exhibited much better inhibition of erosion and dishing while maintaining the desired high removal rates and selectivity.

[0051] Among the polymers used in CMP slurries, the disclosed dicationic polymers or copolymers are surprisingly not described as additives for use in CMP slurries.

[0052] The present invention discloses the synthesis of dicationic polymers or copolymers and demonstrates the use of the synthesized dicationic polymers or copolymers in CMP slurries to reduce the described problems of dishing and erosion in highly selective tungsten slurries.

[0053] All references, including publications, patent applications, and patents, cited in this specification are herein incorporated by reference to the same extent as if each reference was individually and specifically indicated to be incorporated by reference and was set forth in its entirety herein.

[0054] In the context of describing the present invention (particularly in the context of the claims below), the use of the terms "a," "an," and "the," and similar referents, should be construed to encompass both the singular and the plural, unless otherwise stated herein or otherwise clearly contradicted by context. The terms "comprising," "having," "including," and "containing" should be construed as open-ended terms (i.e., meaning "including, but not limited to"), unless otherwise indicated. The recitation of ranges of values ​​herein is merely intended to be used as a shorthand method of separately referring to each individual value falling within the range, unless otherwise stated herein, and each individual value is incorporated herein by reference as if it were separately recited herein. All methods described herein may be performed in any suitable order unless otherwise stated herein or otherwise clearly contradicted by context. The use of any examples or exemplary language (e.g., "such as") provided herein is intended merely to better clarify the invention and does not impose limitations on the scope of the invention unless specifically claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. The use of the term "comprising" in the specification and claims includes the narrower language of "consisting essentially of" and "consisting of."

[0055] Embodiments are described herein, including the best mode known to the inventors for carrying out the invention. Variations on these embodiments will become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors anticipate that such variations will occur to those of ordinary skill in the art, and the inventors intend the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Furthermore, any combination of the above-described elements in all possible variations thereof is encompassed by the present invention unless otherwise indicated herein or otherwise clearly contradicted by context.

[0056] For ease of reference, "microelectronic device" corresponds to semiconductor substrates, flat panel displays, phase change memory devices, solar panels and other products including solar cell substrates, photovoltaic devices, and microelectromechanical systems (MEMS) fabricated for use in microelectronics, integrated circuits, or computer chip applications. Solar cell substrates include, but are not limited to, silicon, amorphous silicon, polycrystalline silicon, single crystal silicon, CdTe, copper indium selenide, copper indium sulfide, and gallium arsenide on gallium. Solar cell substrates may be doped or undoped. It should be understood that the term "microelectronic device" is not intended to be limiting in any way and includes any substrate that ultimately becomes a microelectronic device or microelectronic assembly.

[0057] As used herein, "substantially free" is defined as less than 0.001% by weight. "Substantially free" also includes 0.000% by weight. The term "free" means 0.000% by weight.

[0058] As used herein, "about" is intended to correspond to ±5%, preferably ±2% of the stated value.

[0059] In all compositions where particular components of the composition are discussed with reference to a weight percent range that includes a lower limit of zero, it is understood that such components may or may not be present in various specific embodiments of the composition, and that when such components are present, they may be present in concentrations as low as 0.00001 weight percent, based on the total weight of the composition in which such component is used.

[0060] The CMP slurry in the present invention comprises a dicationic polymer or copolymer.

[0061] More specifically, the CMP slurry contains an abrasive, a dicationic polymer or copolymer, an oxidizer (i.e., an oxidizer that is not a free radical generator), an activator or catalyst, additives, and water, and optionally contains a corrosion inhibitor, a dishing reducer, a stabilizer, and a pH adjuster. The pH of the slurry is 1 to 14, preferably 1 to 7, more preferably 1 to 6, and most preferably 1.5 to 4.

[0062] The CMP slurry may further include surfactants, dispersants, chelating agents, film-forming corrosion inhibitors, biocides, and polish enhancement agents.

[0063] abrasives Abrasives used in CMP slurries include, but are not limited to, inorganic oxide particles, metal oxide coated inorganic oxide particles, organic polymer particles, metal oxide coated organic polymer particles, surface modified abrasive particles, and combinations thereof.

[0064] The abrasives used in the CMP slurry may be activator-containing particles (ie, abrasives having an activator coating) or activator-free particles.

[0065] Inorganic oxide particles include, but are not limited to, ceria, silica, alumina, titania, germania, spinel, tungsten oxides or nitrides, zirconia particles, or any of the above doped with one or more other minerals or elements, and any combination thereof. Oxide abrasives can be produced by any of a variety of methods, including sol-gel, hydrothermal, hydrolysis, plasma, pyrogenic, aerogel, fuming, and precipitation methods, and any combination thereof.

[0066] Precipitated inorganic oxide particles can be obtained by known processes by reaction of metal salts with acids or other precipitating agents. Pyrolytic metal oxide and / or metalloid oxide particles can be obtained by hydrolysis of suitable vaporizable starting materials in an oxygen / hydrogen flame. One example is pyrolytic silicon dioxide from silicon tetrachloride. Pyrolytic oxides such as aluminum oxide, titanium oxide, zirconium oxide, silicon dioxide, cerium oxide, germanium oxide, and vanadium oxide, as well as chemical and physical mixtures thereof, are suitable.

[0067] Metal oxide coated inorganic oxide particles include, but are not limited to, ceria-coated or alumina-coated inorganic oxide particles such as ceria-coated colloidal silica, alumina-coated colloidal silica, ceria-coated high-purity colloidal silica, alumina-coated high-purity colloidal silica, ceria-coated alumina, ceria-coated titania, alumina-coated titania, ceria-coated zirconia, alumina-coated zirconia, or any other ceria-coated or alumina-coated inorganic oxide particle.

[0068] The metal oxide coated organic polymer particles are selected from the group consisting of ceria coated organic polymer particles and zirconia coated organic polymer particles.

[0069] Organic polymer particles include, but are not limited to, polystyrene particles, polyurethane particles, polyacrylate particles, or any other organic polymer particles.

[0070] Colloidal silica particles and high purity colloidal silica particles are preferred abrasive particles. The silica may be precipitated silica, fumed silica, silica fumed, pyrogenic silica, silica doped with one or more adjutants, or any other silica-based compound.

[0071] Colloidal silica particles and high-purity colloidal silica particles used as abrasives also include silica particles whose surfaces have been chemically modified by chemical coupling reactions. This reaction allows the surface of such silica particles to have different chemical functional groups and to have positive or negative charges under different application pH conditions in CMP slurries. For example, amino-polyorganosiloxane-coated silica particles are disclosed in U.S. Patent Application No. 63 / 269,585, filed March 18, 2022. Examples of such surface-chemically modified silica particles include, but are not limited to, SiO2-R-NH2 and -SiO-R-SO3M, where R is, for example, (CH2), where n is in the range of 1 to 12. n group, and M can be, for example, sodium, potassium, or ammonium.

[0072] In alternative embodiments, the silica may be produced by a process selected from the group consisting of, for example, a sol-gel process, a hydrothermal process, a plasma process, a vaporization process, a precipitation process, and any combination thereof.

[0073] The abrasive is generally in the form of abrasive particles, typically in the form of multiple abrasive particles of one material or a combination of different materials. Generally, suitable abrasive particles are roughly spherical and have an effective diameter of about 10 to 700 nm, about 20 to 500 nm, or about 30 to 300 nanometers (nm), although individual particle sizes can vary. Particle size can be measured by dynamic light scattering (DLS). Abrasives in the form of aggregated or agglomerated particles are preferably further processed to form individual abrasive particles.

[0074] The abrasive particles may be purified using suitable methods such as ion exchange to remove metal impurities, which may help improve colloidal stability. Alternatively, high purity abrasive particles are used.

[0075] In general, the above-mentioned abrasives may be used alone or in combination with each other. To obtain superior performance, it may be advantageous to combine two or more abrasive particles of different sizes or different abrasive types.

[0076] The concentration of the abrasive may range from 0.01% to 30% by weight, preferably from about 0.05% to about 20% by weight, more preferably from about 0.01 to about 10% by weight, and most preferably from 0.1% to 2% by weight. Weight percentages are based on the composition. The content is 0.05% by weight to about 10% by weight, and more preferably about 0.1% by weight to about 2% by weight.

[0077] additives The CMP slurry of the present invention includes an additive that is a dicationic polymer or copolymer.

[0078] Yin, K. et al. reported on a battery using a polymer electrolyte ("Polymer electrolytes based on dicationic polymeric ionic liquids: application in lithium metal batteries" in Journal of Materials Chemistry A 2015, 3 (1), 170).

[0079] Cao, W. et al. reported on a porous membrane using a polyelectrolyte ("Dual-Cationic Poly(ionic liquid)s Carrying 1,2,4-Triazolium and Imidazolium Moieties: Synthesis and Formation of a Single-Component Porous Membrane" ACS Macro Letters 2021, 10 (1), 161).

[0080] Compared to polymers from the prior art, dicationic or dicationic polymers or copolymers have an increased charge density per molecular weight of repeating unit and combine different types of cations in the repeating unit, opening up new design possibilities.

[0081] Thus, the dicationic polymers or copolymers of the present invention have unique properties that help reduce erosion in highly selective metal CMP slurries.

[0082] Negatively charged polymers are generally capable of electrostatic interactions with oppositely charged surfaces, such as positively charged tungsten surfaces, and therefore, the use of optimized amounts and tailored polymers can significantly increase the selectivity between metal and oxide layer removal while reducing dishing effects.

[0083] At low pH values ​​below 2.5, the SiO2 layer, as a conventional standard oxide material, is not partially negatively charged at all. 5 In other words, to prevent oxide erosion while simultaneously preventing metal dishing, the polymers used require a more tailored design beyond a purely cationic approach.

[0084] Surprisingly, specifically designed dicationic polymers or copolymers have been shown to exhibit very low dishing and erosion behavior. This unique class of polymers can be used as shape-controlling additives and is a valuable tool for designing next-generation slurries.

[0085] The dicationic polymer or copolymer formed by at least one dicationic monomer has the structure (I): [ka] During the ceremony, P1 represents a polymerizable group, Sp1 and Sp2 each independently represent a spacer group or a single bond; R1, R2, and R3 are each independently H or a substituted or unsubstituted aliphatic aromatic moiety selected from the group consisting of: (1) alkyl having less than 12 C atoms, less than 6 C atoms, less than 4 C atoms, or less than 2 C atoms, preferentially CH3 or CH2-CH3, and (2) phenyl, pyridinyl, pyrimidyl, furanyl, or any nitrogen-containing 5-membered ring, preferentially pyridinyl or pyrimidyl, and (3) a combination of (1) and (2); Cat denotes, for each occurrence, a cationic group, preferentially a cationic group of ammonium, guanidinium, triazolium, phosphonium, pyridinium or triazolium type; X - means an anionic counterion.

[0086] The polymerizable group P1 is selected from groups containing a C=C double bond.

[0087] The anionic counterion is selected from the group consisting of halide (F-, Cl-, Br-, I-), BF4-, PF6-, carboxylate, malonate, citrate, carbonate, fumarate, MeOSO3-, MeSO3-, CF3COO-, CF3SO3-, nitrate, or sulfate.

[0088] The dicationic polymer or copolymer is formed by a polymerization method selected from the group consisting of free radical polymerization, reversible addition-fragmentation chain transfer polymerization (RAFT), nitroxide-mediated polymerization (NMP), atom transfer reaction polymerization (ATRP), ring-opening polymerization (ROMP), or polycondensation reaction.

[0089] Aspect 5. The dicationic polymer or copolymer of any one of aspects 1 to 4, wherein the dicationic polymer or copolymer has block-copolymer properties.

[0090] Examples of dicationic polymers or copolymers include, but are not limited to, poly(3-ethyl-1-(3-(1-vinyl-1H-imidazol-3-ium-3-yl)propyl)-1H-imidazol-3-ium dibromide), poly(3-(tributylphosphino)propyl)-1-vinyl-1H-imidazol-3-ium dibromide), poly(3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium dibromide), and poly(3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium-co-N-vinyl-pyrrolidone dibromide).

[0091] The additive has a concentration in the range of about 0.00001% to 1.0% by weight, about 0.0001% to 0.5% by weight, about 0.00025% to 0.1% by weight, or about 0.0005% to 0.05% by weight.

[0092] oxidizing agent The CMP slurry of the present invention includes an oxidizing agent or oxidizer for chemical etching of materials.

[0093] The oxidizer of a CMP slurry is present in a fluid composition that contacts a substrate and assists in the chemical removal of target materials on the substrate surface. Thus, the oxidizer component is believed to enhance or increase the material removal rate of the composition. Preferably, the amount of oxidizer in the composition is sufficient to assist the chemical removal process, while at the same time being as low as possible to minimize similar or related issues, such as handling, environmental, or cost.

[0094] Advantageously, in one embodiment of the present invention, the oxidizing agent is a component that generates free radicals when exposed to at least one activating agent, resulting in an increased etch rate for at least selected structures. The free radicals discussed below oxidize most metals, making the surface more susceptible to oxidation by other oxidizing agents. However, because some oxidizing agents do not readily form free radicals when exposed to activating agents, oxidizing agents are classified separately from the "compounds that generate free radicals" discussed below, and in some embodiments, it is advantageous to have one or more oxidizing agents that provide tailored or preferential etch rates for various combinations of metals that may be present on a substrate.

[0095] As is known in the art, some oxidizers are more suitable for certain components than others. In some embodiments of the present invention, the selectivity of a CMP system for one metal as opposed to another metal is maximized, as is known in the art. However, in certain embodiments of the present invention, the combination of oxidizers is selected to provide substantially similar CMP rates (as opposed to simple etch rates) for the combination of conductor and barrier.

[0096] In one embodiment, the oxidizing agent is an inorganic or organic per-compound.

[0097] Percompounds are generally defined as compounds containing elements in their highest oxidation state, such as perchloric acid, or compounds containing at least one peroxy group (—OO—), such as peracetic acid and perchromic acid.

[0098] Suitable per-compounds containing at least one peroxy group include, but are not limited to, peracetic acid or its salts, percarbonates, and organic peroxides such as benzoyl peroxide, urea hydrogen peroxide, and / or di-t-butyl peroxide.

[0099] Suitable per compounds containing at least one peroxy group include peroxides. As used herein, the term "peroxide" encompasses ROO-R', as well as salts and adducts thereof, where R and R' are each independently H, C1-C6 linear or branched alkyl, alkanol, carboxylic acid, ketone (for example), or amine, each of which may be independently substituted with one or more benzyl groups, which may themselves be substituted with OH or C1-C5 alkyl (e.g., benzoyl peroxide). Thus, the term includes common examples such as hydrogen peroxide, performic acid, peracetic acid, propane peroxoic acid, substituted or unsubstituted butane peroxoic acid, hydroperoxy-acetaldehyde, and the like, and also encompasses common complexes of peroxides, such as urea peroxide.

[0100] Suitable percompounds containing at least one peroxy group include persulfates. As used herein, the term "persulfates" includes monopersulfates, dipersulfates, and their acids, salts, and adducts. For example, peroxydisulfates, peroxymonosulfates, and / or peroxymonosulfates, Caro's acids, and salts thereof, such as potassium peroxymonosulfate, but preferably non-metal salts such as ammonium peroxymonosulfate.

[0101] Suitable per-compounds containing at least one peroxy group include the perphosphates defined above, including peroxydiphosphates.

[0102] Ozone is also a suitable oxidizing agent, either alone or in combination with one or more other suitable oxidizing agents.

[0103] Suitable per-compounds that do not contain a peroxy group include, but are not limited to, periodic acid and / or any salts of periodic acid (hereinafter "periodates"), perchloric acid and / or any salts of perchloric acid (hereinafter "perchlorates"), perbromic acid and / or any salts of perbromic acid (hereinafter "perbromates"), and perboric acid and / or any salts of perboric acid (hereinafter "perborates").

[0104] Other oxidizing agents are also suitable components of the compositions of the present invention. Iodate is a useful oxidizing agent.

[0105] Two or more oxidizing agents may be combined to obtain synergistic performance benefits.

[0106] In most embodiments of the present invention, the oxidizing agent is selected from the group consisting of peroxy compounds selected from the group consisting of hydrogen peroxide, urea peroxide, performic acid, peracetic acid, propane peroxoacid, substituted or unsubstituted butane peroxoacid, hydroperoxy-acetaldehyde, potassium periodate, and ammonium peroxymonosulfate; and non-peroxy compounds selected from the group consisting of ferric nitrite, KClO, KBrO, and KMnO.

[0107] In some embodiments, the preferred oxidizing agent is hydrogen peroxide.

[0108] The oxidizer concentration may range from about 0.01% to 30% by weight, with a preferred concentration of oxidizer being from about 0.1% to 20% by weight and a more preferred concentration of oxidizer being from about 0.5% to about 10% by weight. Weight percentages are based on the composition.

[0109] activator An activator or catalyst is a substance that interacts with an oxidizer to promote the formation of free radicals by at least one free radical-producing compound present in the fluid.

[0110] The activator may be a metal-containing compound, particularly a metal selected from the group consisting of metals known to activate the Fenton reaction process in the presence of an oxidizing agent such as hydrogen peroxide.

[0111] The activator may be a non-metal-containing compound. Iodine is useful, for example, with hydrogen peroxide to form free radicals.

[0112] If the activator is a metal ion or metal-containing compound, it is present in a thin layer attached to the surface of the solid in contact with the fluid. If the activator is a non-metal-containing material, it may be dissolved in the fluid. The activator is preferably present in an amount sufficient to promote the desired reaction.

[0113] Activators include, but are not limited to, (1) inorganic oxide particles coated with a transition metal selected from the group consisting of iron, copper, manganese, cobalt, cerium, and combinations thereof; (2) soluble catalysts, including, but not limited to, iron(III) nitrate, ammonium iron(III) oxalate trihydrate, iron(III) citrate tribasic monohydrate, iron(III) acetylacetonate, and the iron(III) sodium salt hydrate of ethylenediaminetetraacetic acid; metal compounds having multiple oxidation states selected from the group consisting of Ag, Co, Cr, Cu, Fe, Mo, Mn, Nb, Ni, Os, Pd, Ru, Sn, Ti, V; and combinations thereof.

[0114] The amount of activator in the slurry is in the range of about 0.00001 wt.% to 5 wt.%, about 0.0001 wt.% to 2.0 wt.%, about 0.0005 wt.% to 1.0 wt.%, or about 0.001 wt.% to 0.5 wt.%.

[0115] water The polishing composition is aqueous and therefore contains water. In the composition, water functions in various ways, such as to dissolve one or more solid components of the composition, as a carrier for the components, as an aid in removing polishing residues, and as a diluent. Preferably, the water used in the cleaning composition is deionized (DI) water.

[0116] For most applications, water will comprise, for example, about 10 to about 90% or 90% water by weight. Other preferred embodiments may include about 30 to about 95% water by weight. Still other preferred embodiments may include about 50 to about 90% water by weight. Still other preferred embodiments may include an amount of water to achieve the desired weight percentage of the other ingredients.

[0117] Corrosion inhibitors (if desired) Corrosion inhibitors useful in the CMP compositions disclosed herein include, but are not limited to, nitrogen-containing ring compounds such as 1,2,3-triazole, 1,2,4-triazole, 1,2,3-benzotriazole, 5-methylbenzotriazole, benzotriazole, 1-hydroxybenzotriazole, 4-hydroxybenzotriazole, 3-amino-1,2,4-triazole, 4-amino-4H-1,2,4-triazole, 5-aminotriazole, benzimidazole, benzothiazoles such as 2,1,3-benzothiadiazole, triazine thiols, triazine dithiols, and triazine trithiols, pyrazoles, imidazoles, isocyanurates such as 1,3,5-tris(2-hydroxyethyl)isocyanurate, and mixtures thereof. Preferred corrosion inhibitors are 1,2,4-triazole, 5-aminotriazole, and 1,3,5-tris(2-hydroxyethyl)isocyanurate.

[0118] The amount of corrosion inhibitor in the slurry is in the range of less than 1.0 wt%, preferably less than 0.5 wt%, or more preferably less than 0.25 wt%.

[0119] dishing reducer (if desired) The CMP composition may further comprise a dishing-reducing agent or dishing reducer selected from the group consisting of sarcosinates and related carboxylic acid compounds; hydrocarbon-substituted sarcosinates; amino acids; organic polymers and copolymers having molecules containing ethylene oxide repeat units, such as polyethylene oxide (PEO); ethoxylated surfactants; nitrogen-containing heterocycles without nitrogen-hydrogen bonds, sulfides, oxazolidines, or a mixture of functional groups in one compound; nitrogen-containing compounds having three or more carbon atoms that form alkylammonium ions; aminoalkyls having three or more carbon atoms; polymeric corrosion inhibitors having at least one nitrogen-containing heterocyclic ring or repeating group of tertiary or quaternary nitrogen atoms; dicationic amine compounds; cyclodextrin compounds; polyethyleneimine compounds; glycolic acid; chitosan; sugar alcohols; polysaccharides; alginate compounds; and sulfonic acid polymers. Glycine is a preferred dishing-reducing agent.

[0120] When present, the amount of dishing reducing agent is in the range of about 0.001 wt % to 2.0 wt %, preferably 0.005 wt % to 1.5 wt %, and more preferably 0.01 wt % to 1.5 wt %, based on weight per weight of the total CMP composition.

[0121] Stabilizers (if desired) The composition may also include one or more of a variety of optional additives. Suitable optional additives include stabilizers. These optional additives are generally used to facilitate or promote stabilization of the composition against settling, flocculation (including particle precipitation, aggregation, or agglomeration, and the like), and decomposition. Stabilizers may be used to extend the pot life of oxidizing agents, including compounds that generate free radicals, by sequestering activators, deactivating free radicals, or stabilizing compounds that otherwise form free radicals.

[0122] Some materials are useful for stabilizing hydrogen peroxide. One exception to metal contamination is the presence of selected stabilizing metals, such as tin. In some embodiments of the present invention, tin may be present in small amounts, typically less than about 25 ppm, e.g., about 3 to about 20 ppm. Similarly, zinc is often used as a stabilizer. In some embodiments of the present invention, zinc may be present in small amounts, typically less than about 20 ppm, e.g., about 1 to about 20 ppm. In another preferred embodiment, the fluid composition contacting the substrate has less than 500 ppm, e.g., less than 100 ppm, of dissolved metals with multiple oxidation states, excluding tin and zinc. In the most preferred commercial embodiment of the present invention, the fluid composition contacting the substrate has less than 9 ppm, e.g., less than 2 ppm, of dissolved metals with multiple oxidation states, excluding tin and zinc. In some preferred embodiments of the present invention, the fluid composition contacting the substrate has less than 50 ppm, preferably less than 20 ppm, and more preferably less than 10 ppm, of dissolved metals, excluding tin and zinc, in total.

[0123] Since dissolved metals are generally not recommended, non-metal-containing oxidizers, which are typically present in the form of a salt, e.g., a persulfate, are preferably in the form of an acid and / or an ammonium salt, such as ammonium persulfate.

[0124] Other stabilizers include free radical quenchers. As discussed, these will reduce the usefulness of the generated free radicals. Therefore, even if present, they are preferably present in small amounts. Most antioxidants, i.e., vitamin B, vitamin C, citric acid, and the like, are free radical quenchers. Most organic acids are free radical quenchers, but three have effective and other beneficial stabilizing properties: phosphonic acid, oxalic acid, which is a binding agent, and gallic acid, which is a non-radical scavenging sequestering agent.

[0125] Additionally, carbonates and phosphates are believed to bind to the activator and inhibit fluid access. Carbonates are particularly useful because they can be used to stabilize the slurry, but the stabilizing ions can be readily removed with a small amount of acid. A useful stabilizing agent for absorbed activators can be a film-forming agent that forms a film on the silica particles.

[0126] Suitable stabilizers include organic acids such as adipic acid, phthalic acid, citric acid, malonic acid, orthophthalic acid, and phosphoric acid; substituted or unsubstituted phosphonic acids, i.e., phosphonate compounds; nitriles; and other ligands, such as those that bind to activators and thereby reduce reactions that decompose oxidizing agents, as well as combinations of any of the above. As used herein, acid stabilizer refers to both the acid stabilizer and its conjugate base. That is, various acid stabilizers may be used in their conjugate form. For example, in this specification, for the acid stabilizers mentioned above, an adipic acid stabilizer includes adipic acid and / or its conjugate base, a carboxylic acid stabilizer includes a carboxylic acid and / or its conjugate base, a carboxylate, and so on. Suitable stabilizers, used alone or in combination with one or more other stabilizers, slow the rate at which an oxidizing agent, such as hydrogen peroxide, decomposes when mixed into a CMP slurry.

[0127] On the other hand, the presence of a stabilizer in the composition can impair the effectiveness of the activator. The amount should be adjusted to meet the required stability while minimizing adverse effects on the effectiveness of the CMP system. Generally, any of these optional additives should be present in an amount sufficient to substantially stabilize the composition. The required amount will vary depending on the specific additive selected and the specific configuration of the CMP composition, such as the surface properties of the abrasive component. If too little additive is used, the additive will have little or no effect on the stability of the composition. On the other hand, if too much additive is used, the additive may contribute to the formation of undesirable bubbles and / or agglomerates in the composition.

[0128] Generally, an appropriate amount of these stabilizers is within the range of about 0.0001 to 5% by weight, preferably about 0.00025 to 2% by weight, and more preferably about 0.0005 to about 1% by weight, based on the weight of the composition. The stabilizer may be added directly to the composition or may be applied to the surface of the abrasive component of the composition.

[0129] pH adjuster (if desired) The compositions disclosed herein contain a pH adjuster. The pH adjuster is typically used in the compositions disclosed herein to increase or decrease the pH of the polishing composition. The pH adjuster can be used, as needed, to improve the stability of the polishing composition, adjust the ionic strength of the polishing composition, and improve safety in handling and use.

[0130] Suitable pH adjusters for lowering the pH of the polishing composition include, but are not limited to, nitric acid, sulfuric acid, tartaric acid, succinic acid, citric acid, malic acid, malonic acid, various fatty acids, various polycarboxylic acids, and mixtures thereof. Suitable pH adjusters for raising the pH of the polishing composition include, but are not limited to, potassium hydroxide, sodium hydroxide, ammonia, tetraethylammonium hydroxide, ethylenediamine, piperazine, polyethyleneimine, modified polyethyleneimine, and mixtures thereof.

[0131] When used, the amount of pH adjuster is preferably within the range of about 0.01% to about 5.0% by weight, based on the total weight of the polishing composition, with a preferred range being about 0.01% to about 1% by weight, or about 0.05% to about 0.15% by weight.

[0132] The pH of the slurry is 1-14, preferably 1-7, more preferably 1-6, and most preferably 1.5-4.

[0133] surfactant (if desired) The compositions disclosed herein optionally contain a surfactant, which in part helps protect the wafer surface during and after polishing to reduce defects on the wafer surface. Surfactants can also be used to control the removal rate of some of the films used in polishing, such as low-K dielectrics. Suitable surfactants include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and mixtures thereof.

[0134] Nonionic surfactants may be selected from a variety of chemical species including, but not limited to, long chain alcohols, ethoxylated alcohols, ethoxylated acetylenic diol surfactants, polyethylene glycol alkyl ethers, propylene glycol alkyl ethers, glucoside alkyl ethers, polyethylene glycol octylphenyl ethers, polyethylene glycol alkylphenyl ethers, glycerol alkyl esters, polyoxyethylene glycol sorbitone alkyl esters, sorbitone alkyl esters, cocamide monoethanolamine, cocamide diethanolamine dodecyldimethylamine oxide, block copolymers of polyethylene glycol and polypropylene glycol, polyethoxylated tallow amine, fluorosurfactants.

[0135] The molecular weight of surfactants can range from a few hundred to over a million. The viscosity of these materials also has a very wide distribution.

[0136] Anionic surfactants include, but are not limited to, alkyl carboxylates, alkyl polyacrylates, alkyl sulfates, alkyl phosphates, alkyl bicarboxylates, alkyl bisulfates, alkyl biphosphates, etc.; alkoxy carboxylates, alkoxy sulfates, alkoxy phosphates, alkoxy bicarboxylates, alkoxy bisulfates, alkoxy biphosphates, etc.; and salts with appropriate hydrophobic tails, such as substituted aryl carboxylates, substituted aryl sulfates, substituted aryl phosphates, substituted aryl bicarboxylates, substituted aryl bisulfates, and substituted aryl biphosphates. Counterions for these surfactants include, but are not limited to, potassium, ammonium, and other cations. The molecular weights of these anionic surface wetting agents range from several hundred to several hundred thousand.

[0137] Cationic surfactants have a net positive charge on the main portion of the molecular backbone and are typically molecular halides with a hydrophobic chain and a cationic charge center such as an amine, quaternary ammonium, benzyalkonium, and alkylpyridinium ion.

[0138] In another embodiment, the surfactant may be an amphoteric surfactant, which has both positive (cationic) and negative (anionic) charges on the main molecular chain, along with their corresponding counterions. The cationic portion is based on a primary, secondary, or tertiary amine, or a quaternary ammonium cation. The anionic portion may be more variable and may include sulfonates, such as the sultaine CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate) and cocamidopropyl hydroxysultaine. Betaines, such as cocamidopropyl betaine, have a carboxylate with ammonium. Some amphoteric surfactants may also have a phosphate anion with an amine or ammonium, such as the phospholipids phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine, and sphingomyelin.

[0139] Examples of surfactants also include, but are not limited to, sodium dodecyl sulfate, sodium lauryl sulfate, ammonium dodecyl sulfate, secondary alkane sulfonates, alcohol ethoxylates, acetylenic surfactants, and any combination thereof. Examples of suitable commercially available surfactants include the TRITON™, Tergitol™, and DOWFAX™ series surfactants manufactured by Dow Chemicals, as well as various surfactants in the SURFYNOL™, DYNOL™, Zetasperse™, Nonidet™, and Tomadol™ surfactant series manufactured by Air Products and Chemicals. Suitable surfactants may also include polymers with ethylene oxide (EO) and propylene oxide (PO) groups. An example of an EO-PO polymer is Tetronic™ 90R4 manufactured by BASF Chemicals.

[0140] When used, the amount of surfactant typically ranges from 0.0001% to about 1.0% by weight, based on the total weight of the barrier CMP composition. When used, the preferred range is from about 0.010% to about 0.1% by weight.

[0141] Chelating agent (if desired) A chelating agent may be optionally used in the compositions disclosed herein to increase the affinity of the chelating ligand for metal cations. A chelating agent may also be used to prevent the accumulation of metal ions on the pad, which can cause pad soiling and instability in removal rate. Suitable chelating agents include, but are not limited to, amine compounds such as ethylenediamine, aminopolycarboxylic acids such as ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA); aromatic acids such as benzenesulfonic acid, 4-tolylsulfonic acid, and 2,4-diaminobenzosulfonic acid; non-aromatic organic acids such as itaconic acid, malic acid, malonic acid, tartaric acid, citric acid, oxalic acid, gluconic acid, lactic acid, mandelic acid, or salts thereof;Glycine, serine, proline, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, ornithine, selenocysteine, tyrosine, sarcosine, bicine, tricine, aceglutamide, N-acetylaspartic acid, acetylcarnitine, acetylcysteine, N-acetylglutamic acid, acetylleucine, acivicin , S-Adenosyl-L-homocysteine, Agaritine, Alanosine, Aminohippuric Acid, L-Arginine Ethyl Ester, Aspartame, Aspartylglucosamine, Benzylmercapturic Acid, Biocytin, Brivanib Alaninate, Carbocysteine, N(6)-Carboxymethyllysine, Carglumic Acid, Cilastatin, Cithiolone, Coprine, Dibromotyrosine, Dihydroxyphenylglycine, Eflornithine, Fenclonine, 4-Fluoro-L-threonine, N- Formylmethionine, γ-L-glutamyl-L-cysteine, 4-(γ-glutamylamino)butanoic acid, glutaurine, glycocyamine, hadacidin, hepapressin, lisinopril, lymecycline, N-methyl-D-aspartic acid, N-methyl-L-glutamic acid, milacemide, nitrosoproline, nocardicin A, nopaline, octopine, ombrulin, opine, orthanilic acid, oxaceprol, polylysine, remacemide, salicylic acid Various amino acids and their derivatives, such as phosphonic acid, silk amino acids, stampidine, tabtoxin, tetrazolylglycine, thiorphan, thymectacin, tiopronin, tryptophan tryptophylquinone, valacyclovir, valganciclovir, and the like, as well as phosphonic acids and their derivatives, such as octylphosphonic acid, aminobenzylphosphonic acid, and the like, and combinations and salts thereof;

[0142] Chelating agents may be used when there is a need to chemically bond, for example, copper cations and tantalum cations to facilitate dissolution of copper oxide and tantalum oxide to obtain a desired removal rate of copper lines, vias, or trenches, and barrier layers or films.

[0143] If used, the amount of chelating agent is preferably in the range of about 0.01% to about 3.0% by weight, more preferably about 0.4% to about 1.5% by weight, based on the total weight of the composition.

[0144] Biocides (if desired) The CMP formulations disclosed herein may also include additives for controlling biological growth, such as biocides. Some additives for controlling biological growth are disclosed in U.S. Pat. No. 5,230,833 and U.S. Patent Application Publication No. 2002 / 0025762, which are incorporated herein by reference. Biological growth inhibitors include, but are not limited to, tetramethylammonium chloride, tetraethylammonium chloride, tetrapropylammonium chloride, alkylbenzyldimethylammonium chloride and alkylbenzyldimethylammonium hydroxide, where the alkyl chain is in the range of 1 to about 20 carbon atoms, sodium chlorite, sodium hypochlorite, and the isothiazolinone compounds methylisothiazolinone, methylchloroisothiazolinone, and benzisothiazolinone. Some commercially available preservatives include the KATHON™ and NEOLENE™ product series from Dow Chemicals and the Preventol™ series from Lanxess.

[0145] Preferred biocides are isothiozilone compounds such as methylisothiazolinone, methylchloroisothiazolinone, and benzisothiazolinone.

[0146] The CMP polishing composition optionally contains a biocide in the range of 0.0001% to 0.10% by weight, preferably 0.0001% to 0.005% by weight, and more preferably 0.0002% to 0.0025% by weight, to prevent bacterial and fungal growth during storage.

[0147] The compositions disclosed herein may be prepared in concentrated form and then diluted with DI water at the point of use. Other components, such as oxidizers, may not be added in concentrated form but may be added at the point of use to minimize incompatibilities between components in concentrated form. The compositions disclosed herein may be prepared with two or more components that can be mixed prior to use. [Example]

[0148] General experimental procedure Unless otherwise noted, all percentages are by weight.

[0149] Part 1. Synthesis of dicationic polymers or copolymers All reagents and solvents were purchased from Sigma-Aldrich (Merck) of the highest commercially available grade and were used as received unless otherwise specified.

[0150] Characterization methods NMR spectra were recorded on a 500 MHz Bruker Avance II+ spectrometer using deuterated solvents from Sigma-Aldrich (Merck). Chemical shifts are reported as d values ​​(ppm) and calibrated against the internal standard Si(OMe)4 (0.00 ppm).

[0151] Polycationic polymers were analyzed by size exclusion chromatography (SEC) in HO / MeOH / EtOAc (54 / 23 / 23, v / v / v) containing 10 mM sodium acetate, operated at 40 °C (flow rate: 0.5 mL / min). Measurements were performed on an Agilent 1260 HPLC equipped with a column set consisting of a PSS Novema precolumn and a PSS Novema MAX ultraheight column. Samples were dissolved at 50 °C in an eluent containing 0.1% ethylene glycol as an internal standard. The average molar mass of the polymer was determined from the refractive index signal based on a poly(2-vinylpyridine) calibration curve.

[0152] Example 1: Poly(3-ethyl-1-(3-(1-vinyl-1H-imidazol-3-ium-3-yl)propyl)-1H-imidazol-3-ium dibromide) [ka] Monomer synthesis:

[0153] Synthesis of 3-(3-bromopropyl)-1-vinyl-1H-imidazol-3-ium [ka]

[0154] 1,3-Dibromopropane (CAS: 109-64-8, 107 mL, 1.06 mol) was dissolved in acetonitrile (300 mL), and then 1-vinylimidazole (CAS: 1072-63-5, 10 g, 0.105 mol dissolved in 40 mL of acetonitrile) was added dropwise with stirring at room temperature. The reaction mixture was heated at 65 °C overnight, cooled to room temperature, and ethyl acetate (1 L) was added, precipitating the crude product as an oil. The mixture was concentrated under vacuum and finally purified by column chromatography (silica gel, DCM / MeOH 95:5) to give 21.7 g (70%) of a pale yellow solid.

[0155] 1H NMR(500MHz,DMSO-d6)δ=9.62(t,J=1.6Hz,1H),8.25(t,J=1.9Hz,1H),7.98(t,J=1.9Hz,1H),7.32(dd,J=15.6,8.7Hz,1H),5.9 9(dd,J=15.6,2.4Hz,1H),5.43(dd,J=8.8,2.4Hz,1H),4.34(t,J=7.0Hz,2H),3.58(t,J=6.6Hz,2H),2.41(p,J=6.8Hz,2H)ppm.

[0156] Synthesis of 3-ethyl-1-(3-(1-vinyl-1H-imidazol-3-ium-3-yl)propyl)-1H-imidazol-3-ium dibromide [ka]

[0157] 3-(3-Bromopropyl)-1-vinyl-1H-imidazol-3-ium (4.7 g, 16 mmol) was dissolved in 40 mL of acetonitrile and N-ethylimidazole (CAS: 7098-07-9; 1.9 g, 19 mmol dissolved in 10 mL of acetonitrile) was added dropwise with stirring at room temperature. The reaction mixture was heated at 60 °C overnight, cooled to room temperature, and mixed with ethyl acetate (500 mL), resulting in the precipitation of an oil. The oil was washed with ethyl acetate, dissolved in water, and lyophilized to give 5.7 g (92%) of a solid.

[0158] 1 H NMR(500MHz,DMSO-d6)δ=9.75(d,J=1.6Hz,1H),9.40(t,J=1.7Hz,1H),8.28(t,J= 1.9Hz,1H),8.03(t,J=1.8Hz,1H),7.88(d,J=1.6Hz,2H),7.35(dd,J=15.7,8.7Hz ,1H),6.02(dd,J=15.6,2.4Hz,1H),5.45(dd,J=8.8,2.4Hz,1H),4.31(dt,J=12.2 ,6.9Hz,4H),4.23(q,J=7.3Hz,2H),2.53-2.45(m,2H),1.44(t,J=7.3Hz,3H)ppm.

[0159] polymerization: [ka]

[0160] 3-Ethyl-1-(3-(1-vinyl-1H-imidazol-3-ium-3-yl)propyl)-1H-imidazol-3-ium dibromide) (5.7 g, 14.5 mmol) was dissolved in water (30 mL), and 1,2'-azobis(2-methylpropionamidine) dihydrochloride (V50, CAS: 2997-92-4, 18.5 mg, 0.068 mmol) was added. The mixture was purged with argon for 30 minutes and then heated at reflux overnight. After cooling to room temperature, the solution was mixed with THF (250 mL). The precipitated oil was dissolved in water and purified by cross-flow filtration (MWCO: 5 kDa). The purified polymer was lyophilized to yield 3.15 g (55%) of a white solid.

[0161] 1 H NMR(500MHz,DMSO-d6)δ=10.00(broad s),9.68(broad s),8.07(broad s),7.96(broad s),4.69(broad s),4.42(broad s),4.26(broad s),2.63(broad s),2.05(broad s),1.46(broad s)ppm.

[0162] SEC: Mn:19.0kDa; Mw:41.1kDa; PDI:2.1.

[0163] Example 2: Poly(3-(tributylphosphino)propyl)-1-vinyl-1H-imidazol-3-ium dibromide) [ka] Monomer synthesis:

[0164] Synthesis of 3-(3-bromopropyl)-1-vinyl-1H-imidazol-3-ium according to the same method as described in Example 1 [ka]

[0165] Synthesis of 3-(tributylphosphino)propyl-1-vinyl-1H-imidazol-3-ium dibromide [ka]

[0166] 3-(3-Bromopropyl)-1-vinyl-1H-imidazol-3-ium (5.5 g, 18.6 mmol) was dissolved in 40 mL of acetonitrile and tributylphosphine (CAS: 998-40-3; 4.1 g, 20 mmol dissolved in 10 mL of acetonitrile) was added dropwise with stirring at room temperature. The reaction mixture was heated at 60 °C overnight, cooled to room temperature, and mixed with tert-butyl methyl ether (MTBE, 500 mL), resulting in the precipitation of a solid. The crude product was washed with MTBE and dried under vacuum to give 8 g (71%) of a colorless solid.

[0167] 1 H NMR(500MHz,DMSO-d6)δ=9.76(t,J=1.6Hz,1H),8.29(t,J=1.9Hz,1H),8.06(t,J=1 .8Hz,1H),7.37(dd,J=15.6,8.8Hz,1H),6.03(dd,J=15.6,2.4Hz,1H),5.46(dd,J=8 .7,2.4Hz,1H),4.35(t,J=6.9Hz,2H),2.38-2.26(m,1H),2.32(s,1H),2.29-2.21( m,6H),2.16(dq,J=12.4,7.4Hz,2H),1.53-1.36(m,12H),0.92(t,J=7.1Hz,9H)ppm.

[0168] polymerization: [ka]

[0169] 3-(Tributylphosphino)propyl-1-vinyl-1H-imidazol-3-ium dibromide (6 g, 12.4 mmol) was dissolved in water (30 mL), and 1,2'-azobis(2-methylpropionamidine) dihydrochloride (V50, CAS: 2997-92-4, 13.9 mg, 0.05 mmol) was added. The mixture was purged with argon for 30 minutes and then heated at reflux overnight. The solution was cooled to room temperature and purified by cross-flow filtration (MWCO: 3 kDa). The purified polymer was lyophilized to yield 2.1 g (35%) of a white solid.

[0170] 1 H NMR(500MHz,DMSO-d6)δ=10.00(broad s), 8.44(broad s),4.54(broad s),2.22(broad s),1.54(broad s),1.43(broad s),0.93(broad s)ppm.

[0171] SEC: Mn:11.0kDa; Mw:22.3kDa; PDI:2.0.

[0172] Example 3: Poly(3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium dibromide) [ka] Monomer synthesis:

[0173] Synthesis of 3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium dibromide [ka]

[0174] (2-Bromoethyl)trimethylammonium bromide (CAS: 2758-06-7, 25 g, 101 mmol) was dissolved in 150 mL of acetonitrile and 1-vinylimidazole (CAS: 1072-63-3; 10.7 g, 112.5 mmol) was added dropwise with stirring at room temperature. The reaction mixture was heated at 60 °C overnight, cooled to room temperature, and mixed with ethyl acetate (500 mL), resulting in the precipitation of an oil. The crude product was washed with ethyl acetate, dissolved in water, and lyophilized to give 32.7 g (85%) of a colorless solid.

[0175] 1 H NMR(500MHz,DMSO-d6)δ=9.60(t,J=1.6Hz, 1H),8.18(t,J=1.9Hz,1H),8.00(t,J=1.9Hz,1H),7.29(dd,J=15.6,8.6Hz,1H),5.95(dd,J=15.6,2.6Hz,1H),5.46(dd,J=8.7,2.6Hz,1H),4.82 (t,J=7.1Hz,2H),3.98(t,J=7.1Hz,2H),3.19(s,9H)ppm.

[0176] polymerization: [ka]

[0177] 3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium dibromide (5 g, 14.8 mmol) was dissolved in water (30 mL), and 1,2'-azobis(2-methylpropionamidine) dihydrochloride (V50, CAS: 2997-92-4, 13.6 mg, 0.05 mmol) was added. The mixture was purged with argon for 30 minutes and then heated at reflux overnight. After cooling to room temperature, the solution was mixed with THF (250 mL). The precipitated oil was dissolved in water and purified by cross-flow filtration (MWCO: 5 kDa). The purified polymer was lyophilized to yield 4.7 g (94%) of a white solid.

[0178] 1H NMR(500MHz,DMSO-d6)δ=9.79(broad s), 8.15(broad s),8.01(broad s),4.88(broad s),4.29(broad s),3.3(broad s),2.63(broad s)ppm.

[0179] SEC: Mn:24kDa; Mw:73kDa; PDI:3.0

[0180] Example 4: Poly(3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium-co-N-vinyl-pyrrolidone dibromide) [ka] Monomer synthesis:

[0181] Synthesis of 3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium dibromide [ka]

[0182] The same method as described in Example 3 was used.

[0183] Polymerization Example 4-1: [ka]

[0184] 3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium dibromide (4 g, 11.7 mmol) and 1-vinyl-2-pyrrolidone (CAS: 88-12-0, 3.9 g, 35.2 mmol) were dissolved in DMF / water (1:1, 60 mL) and mixed with 2,2'-azobisisobutyronitrile (AIBN, CAS: 78-67-1, 13.3 mg, 0.08 mmol). The mixture was purged with argon for 30 minutes and then heated at reflux overnight. The solution was cooled to room temperature and mixed with ethyl acetate (500 mL). The precipitated oil was dissolved in water and purified by cross-flow filtration (MWCO: 10 kDa). The purified polymer was lyophilized to yield 3.8 g (48%) of a white solid.

[0185] 1 H NMR(500MHz,DMSO-d6)δ=9.71(broad s), 8.13(broad s),4.84(broad s),4.03(broad s),3.61(broad s),3.26(broad s),2.37(broad s),1.90(broad s)ppm.

[0186] SEC: Mn:35kDa; Mw:119kDa; PDI:3.4

[0187] Polymerization Example 4-2:

[0188] The same method as described in Example 4-1 was used, except that 11.7 g (105.5 mmol) of 1-vinyl-2-pyrrolidone (CAS: 88-12-0) was used. The purified polymer was lyophilized to yield 8.8 g (56%) of a white solid.

[0189] 1H NMR(500MHz,DMSO-d6)δ:9.71(broad s),8.05(broad s),7.76(broad s),4.80(broad s),4.01(broad s),3.74(broad s),3.54(broad s),3.22(broad s),2.27(broad s),2.09(broad s),1.90(broad s),1.62(broad s),1.31(broad s)ppm.

[0190] SEC: Mn:41kDa; Mw:272kDa; PDI:6.6

[0191] Polymerization Example 4-3:

[0192] The same method as in Example 4-1 was used, except that 2 g (5.9 mmol) of 3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium and 12.4 g (111 mmol) of 1-vinyl-2-pyrrolidone (CAS: 88-12-0) were used. The purified polymer was lyophilized to yield 10.3 g (72%) of a white solid.

[0193] 1 H NMR(500MHz,DMSO-d6)δ:9.46(broad s), 8.01(broad s),7.70(broad s),4.78(broad s),3.95(broad s),3.75(broad s),3.56(broad s),3.19(broad s),2.07(broad s),1.87(broad s),1.63(broad s),1.32(broad s)ppm.

[0194] SEC: Mn:29kDa; Mw:207kDa; PDI:7.0.

[0195] Part 2: CMP experiments using the phosphonium-based polymer synthesized in Part 1 The polishing compositions and associated methods described herein are effective for CMP of a wide variety of substrates, including most substrates, and are particularly useful for polishing tungsten substrates.

[0196] In the examples presented below, CMP experiments were performed using the procedures and experimental conditions set out below. Para, Mehta: Å: Angstrom - unit of length BP: Back pressure, unit is psi CMP: Chemical mechanical planarization = chemical mechanical polishing CS: Carrier Speed DF: Downforce: Pressure applied during CMP, in psi min:minutes ml: milliliter mV: millivolt psi: pounds per square inch PS: Polishing tool platen rotation speed, in rpm (revolutions per minute) SF: flow rate of polishing composition, unit is ml / min Silicon oxide films by chemical vapor deposition (CVD) using TEOS: tetraethyl orthosilicate as a precursor Wt%: Weight percent (of the listed ingredient) Removal rate (RR) = (film thickness before polishing - film thickness after polishing) / polishing time Removal rate and selectivity Tungsten removal rate: CMP tool downforce pressure 3.0 psi (approximately 2.1 x 10 4 Tungsten removal rate measured in Pa TEOS removal rate: TEOS removal rate measured at a given downforce pressure. The downforce pressure of the CMP tool was 3.0 psi (approximately 2.1 × 10 4 Pa). SiN removal rate: SiN removal rate measured at a given downforce pressure. The downforce pressure of the CMP tool was 3.0 psi (approximately 2.1×10 4 Pa).

[0197] The CMP tool used in the examples was an AMAT 200 mm Mirra® manufactured by Applied Materials, Inc. 3050 Bowers Avenue, Santa Clara, California, 95054. The polishing tests used an IC1010 polishing pad manufactured by Dow Chemicals on the platen.

[0198] 200 mm diameter silicon wafers coated with tungsten, TEOS, SiN, or tungsten-containing SKW patterned structures were obtained from SKW Associate, Inc., 2920 Scott Blvd., Santa Clara, CA 95054. The polishing time for blanket films was 1 minute. Tungsten removal rates were measured using sheet resistance measurements. TEOS removal was measured using optical methods. Patterned wafers were polished with an Ebara polisher over a time period based on eddy current measurements. The polishing time for patterned wafers was 15 seconds past the endpoint identified by eddy current endpoint detection. Patterned wafers were analyzed with a KLA Tencor P15 profiler (for large feature sizes) or an AFM tool (for small feature sizes).

[0199] The polishing was performed with a table rotation speed of 111 RPM, a carrier rotation speed of 113 RPM, a slurry flow rate of 200 ml / min, and a downforce of 3.0 psi (approximately 2.1 x 10 4 Pa).

[0200] In the polishing process, a substrate (e.g., a blanket W wafer or a patterned W wafer) was placed face down on a polishing pad fixed to the rotating platen of a CMP polisher. In this way, the substrate to be polished and planarized was placed in direct contact with the polishing pad. A wafer carrier system or polishing head was used to hold the substrate in place and apply downward pressure to the backside of the substrate while rotating the platen and substrate during the CMP process. During the CMP process, a polishing composition (slurry) was applied (usually continuously) onto the pad to effectively remove material and planarize the substrate.

[0201] In the following examples, four base CMP slurries (containing no dicationic polymer) were prepared in water using 0.01 wt. % ferric nitrate (iron(III) nitrate), 0.08 wt. % malonic acid (a stabilizer), 2.0 wt. % hydrogen peroxide, 0.1 wt. % glycine, and 0.25 wt. % and 0.3 wt. % of one of the following abrasive particles: Fuso PL-2C silica particles (Base 1); amino-polyorganosiloxane (specifically, 3-aminopropyl-methyldimethoxysilane)-coated silica particles (functionalized at 20 mmol / g and having a base particle size of 80 nm) disclosed in WO 2023 / 178286 A1 (Base 2); Base 3 (functionalized at 48 mmol / g and having a base particle size of 80 nm); and Base 4 (functionalized at 48 mmol / g and having a base particle size of 90 nm). The pH was adjusted to 2.3 with nitric acid.

[0202] Various dicationic polymers were added to the base slurry to obtain working slurries.

[0203] The effect of dicationic polymers on removal rate, erosion, and dishing of tungsten, TEOS, and SiN was examined.

[0204] The removal rate and selectivity of W:TEOS are shown in Table 1. [Table 1]

[0205] As shown in Table 1, the addition of a small amount of the synthesized dicationic polymer resulted in a high tungsten removal rate and a very low TEOS removal rate, resulting in high selectivity.

[0206] Tungsten dishing was tested in various arrays, including a 0.18 x 0.18 micron array (tungsten line width in microns / trench and separating dielectric line width / spacer) (0.18 / 0.18 μm), a 7 x 3 micron (7 / 3 μm), and a 1 x 1 micron array (1 / 1 μm). Wafers were polished for an additional or overpolish (OP) time of 20 seconds after detecting the polishing endpoint of the patterned wafer using eddy current measurements. W line dishing data is shown in Table 2. [Table 2]

[0207] Dishing of the lines is typically greater for wider lines, and in a typical tungsten CMP process, tungsten dishing in the lines of wider line features is desired to be less than 1500 Angstroms (Å).

[0208] As shown in Table 2, adding a small amount of synthetic dicationic polymer resulted in low W line dishing.

[0209] As shown in Table 3, erosion was tested for 7 / 3 μm, 1 / 1 μm, and 50 / 50 μm arrays with 20 seconds of overpolishing. [Table 3]

[0210] Array erosion typically increases with increasing pattern density, and in a typical tungsten CMP process, erosion of less than 1000 Å is desired for high density features, such as 70% and 90% density.

[0211] As shown in Table 3, adding small amounts of synthetic dicationic polymers resulted in low erosion.

[0212] While the principles of the present invention have been described above in connection with preferred embodiments, it is to be clearly understood that this description is made by way of example only and is not intended to limit the scope of the invention. Rather, the detailed description of the preferred exemplary embodiments which follows will provide those skilled in the art with an enabling description for practicing the preferred exemplary embodiments of the invention. Various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention as set forth in the appended claims.

Claims

1. A dicationic polymer or copolymer formed by at least one dicationic monomer having the structure (I): 【Chemistry 1】 During the ceremony, P １ means a polymerizable group, Sp １ and Sp ２ represents independently at each occurrence a spacer group or a single bond; R １ , R ２ , and R ３ are each independently H or (1) alkyl having less than 12 C atoms, less than 6 C atoms, less than 4 C atoms or less than 2 C atoms, preferentially CH ３ or CH ２ -CH ３ and (2) a substituted or unsubstituted aliphatic aromatic moiety selected from the group consisting of phenyl, pyridinyl, pyrimidyl, furanyl, or a nitrogen-containing five-membered ring, preferentially pyridinyl or pyrimidyl, and (3) a combination of (1) and (2), Cat denotes, for each occurrence, a cationic group, preferentially a cationic group of ammonium, guanidinium, triazolium, phosphonium, pyridinium or triazolium type, X － means an anionic counterion, Dicationic polymers or copolymers.

2. The polymerizable group P １ 2. The dicationic polymer or copolymer of claim 1, wherein is selected from groups containing a C=C double bond.

3. The anionic counterion is a halide selected from the group consisting of F-, Cl-, Br-, and I-, BF ４ -, PF ６ -, carboxylate, malonate, citrate, carbonate, fumarate, MeOSO ３ -, MeSO ３ -, CF ３ COO-, CF ３ SO ３ 3. The dicationic polymer or copolymer according to claim 1, wherein the dicationic polymer or copolymer is selected from the group consisting of nitrates, nitrates, and sulfates.

4. 4. The dicationic polymer or copolymer of any one of claims 1 to 3, wherein the dicationic polymer or copolymer is formed by a polymerization method selected from the group consisting of free radical polymerization, reversible addition-fragmentation chain transfer polymerization (RAFT), nitroxide mediated polymerization (NMP), atom transfer reaction polymerization (ATRP), ring-opening polymerization (ROMP), and polycondensation reactions.

5. 5. The dicationic polymer or copolymer of any one of claims 1 to 4, wherein said dicationic polymer or copolymer has block-copolymer properties.

6. 6. The dicationic polymer or copolymer of any one of claims 1 to 5, wherein the dicationic polymer or copolymer is selected from the group consisting of poly(3-ethyl-1-(3-(1-vinyl-1H-imidazol-3-ium-3-yl)propyl)-1H-imidazol-3-ium dibromide), poly(3-(tributylphosphino)propyl)-1-vinyl-1H-imidazol-3-ium dibromide), poly(3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium dibromide), poly(3-(2-(trimethylammonio)ethyl)-1-vinyl-1H-imidazol-3-ium-co-N-vinyl-pyrrolidone dibromide), and combinations thereof.

7. A chemical mechanical planarization composition comprising the dicationic polymer or copolymer of any one of claims 1 to 6.

8. 1. A chemical mechanical planarization composition comprising: an abrasive selected from the group consisting of inorganic oxide particles, metal oxide-coated inorganic oxide particles, organic polymer particles, metal oxide-coated organic polymer particles, and combinations thereof; activator, oxidizing agents, An additive comprising the dicationic polymer or copolymer according to any one of claims 1 to 6. water, and, if desired, corrosion inhibitors, dishing reducing agent, stabilizers, pH adjusters, 1. A chemical mechanical planarization composition comprising:

9. 9. The chemical mechanical planarizing composition of claim 8, wherein the abrasive is in the range of 0.01 wt.% to 30 wt.%, 0.05 wt.% to 20 wt.%, 0.01 wt.% to 10 wt.%, or 0.1 wt.% to 2 wt.%.

10. 10. The chemical mechanical planarization composition of claim 8, wherein the dicationic polymer or copolymer comprising additive is in the range of 0.00001 wt % to 1.0 wt %, 0.0001 wt % to 0.5 wt %, 0.00025 wt % to 0.1 wt %, or 0.0005 wt % to 0.05 wt %.

11. The oxidizing agent is a peroxy compound selected from the group consisting of hydrogen peroxide, urea peroxide, performic acid, peracetic acid, propane peroxoacid, substituted or unsubstituted butane peroxoacid, hydroperoxy-acetaldehyde, potassium periodate, and ammonium peroxymonosulfate; and ferric nitrite, KClO ４ , KBrO ４ , KMnO ４ 11. The chemical mechanical planarization composition of claim 8, wherein the oxidizer is selected from the group consisting of: a non-peroxy compound selected from the group consisting of:

12. The activator is selected from the group consisting of: (1) inorganic oxide particles coated with a transition metal selected from the group consisting of Fe, Cu, Mn, Co, Ce, and combinations thereof; (2) a soluble catalyst selected from the group consisting of iron (III) nitrate, ammonium iron (III) oxalate trihydrate, iron (III) citrate tribasic monohydrate, iron (III) acetylacetonate, and the iron (III) sodium salt hydrate of ethylenediaminetetraacetic acid; (3) a soluble catalyst selected from the group consisting of Ag, Co, Cr, Cu, 12. The chemical mechanical planarizing composition of claim 8, wherein the activator is selected from the group consisting of metal compounds having multiple oxidation states selected from the group consisting of Fe, Mo, Mn, Nb, Ni, Os, Pd, Ru, Sn, Ti, V, and combinations thereof, and the activator is in the range of 0.00001 wt % to 5.0 wt %, 0.0001 wt % to 2.0 wt %, 0.0005 wt % to 1.0 wt %, or 0.001 wt % to 0.5 wt %.

13. 13. The chemical mechanical planarizing composition of claim 8, wherein the corrosion inhibitor is selected from the group consisting of 1,2,3-triazole, 1,2,4-triazole, 1,2,3-benzotriazole, 5-methylbenzotriazole, benzotriazole, 1-hydroxybenzotriazole, 4-hydroxybenzotriazole, 3-amino-1,2,4-triazole, 4-amino-4H-1,2,4-triazole, 5-aminotriazole, benzimidazole, 2,1,3-benzothiadiazole, triazine thiols, triazine dithiols, and triazine trithiols, pyrazoles, imidazoles, isocyanurates such as 1,3,5-tris(2-hydroxyethyl) nitriles, and combinations thereof, and the corrosion inhibitor is in the range of less than 1.0 wt %, less than 0.5 wt %, or less than 0.25 wt %.

14. 14. The chemical mechanical planarizing composition of claim 8, wherein the pH adjuster is selected from the group consisting of: (a) nitric acid, sulfuric acid, tartaric acid, succinic acid, citric acid, malic acid, malonic acid, various fatty acids, various polycarboxylic acids, and mixtures thereof, for lowering the pH; and (b) potassium hydroxide, sodium hydroxide, ammonia, tetraethylammonium hydroxide, ethylenediamine, piperazine, polyethyleneimine, modified polyethyleneimine, and mixtures thereof, for raising the pH.

15. The chemical mechanical planarizing composition of any one of claims 8 to 14, wherein the composition has a pH of 1 to 14, 1 to 7, 1 to 6, or 1.5 to 4.

16. The dishing reducing agent may be selected from the group consisting of sarcosinates and related carboxylic acid compounds; hydrocarbon-substituted sarcosinates; amino acids; organic polymers and copolymers having molecules containing ethylene oxide repeat units, such as polyethylene oxide (PEO); ethoxylated surfactants; nitrogen-containing heterocycles without nitrogen-hydrogen bonds, sulfides, oxazolidines, or mixtures of functional groups in one compound; nitrogen-containing compounds having three or more carbon atoms that form alkylammonium ions; aminoalkyls having three or more carbon atoms; 16. The chemical mechanical planarizing composition of any one of claims 8 to 15, wherein the dishing reducing agent is selected from the group consisting of: a polymeric corrosion inhibitor comprising a heterocyclic ring or a repeating group of tertiary or quaternary nitrogen atoms; a dicationic amine compound; a cyclodextrin compound; a polyethyleneimine compound; glycolic acid; chitosan; a sugar alcohol; a polysaccharide; an alginate compound; and a sulfonic acid polymer; and combinations thereof, and the dishing reducing agent is in the range of 0.001 wt % to 2.0 wt %, 0.005 wt % to 1.5 wt %, or 0.01 wt % to 1.0 wt %.

17. 17. The chemical mechanical planarizing composition of any one of claims 8 to 16, wherein the stabilizing agent is selected from the group consisting of adipic acid, phthalic acid, citric acid, malonic acid, orthophthalic acid, phosphoric acid, substituted or unsubstituted phosphonic acids, nitriles, and combinations thereof, and the stabilizing agent is in the range of 0.0001 to 5 wt %, 0.00025 to 2 wt %, or 0.0005 to 1 wt %.

18. The chemical mechanical planarization composition of any one of claims 8 to 17, wherein the abrasive is silica particles.

19. 19. The chemical mechanical planarization composition of claim 8, wherein the chemical mechanical planarization composition comprises silica particles, poly(vinyl-3-ethyl-1H-imidazol-3-ium-co-tributyl-(4-vinylbenzyl)-phosphonium) bromide chloride, iron(III) nitrate, malonic acid, hydrogen peroxide, and water, and wherein the pH of the composition is from 1.5 to 4.

20. 1. A polishing method for chemical mechanical planarization of a semiconductor substrate having at least one surface containing tungsten, comprising: a) providing a polishing pad; b) providing a chemical-mechanical polishing composition, the chemical-mechanical polishing composition comprising: an abrasive selected from the group consisting of inorganic oxide particles, metal oxide-coated inorganic oxide particles, organic polymer particles, metal oxide-coated organic polymer particles, and combinations thereof; activator, oxidizing agents, An additive comprising the dicationic polymer or copolymer according to any one of claims 1 to 6. water, and, if desired, corrosion inhibitors, dishing reducing agent, stabilizers, pH adjusters, and c) polishing the at least one tungsten-containing surface with the chemical mechanical planarization composition; A polishing method comprising:

21. 21. The polishing method of claim 20, wherein the chemical mechanical planarization composition has the abrasive in the range of 0.01 wt % to 30 wt %, 0.05 wt % to 20 wt %, 0.01 wt % to 10 wt %, or 0.1 wt % to 2 wt %.

22. 22. The polishing method according to claim 20, wherein the additive containing the dicationic polymer or copolymer is in the range of 0.00001 wt % to 1.0 wt %, 0.0001 wt % to 0.5 wt %, 0.00025 wt % to 0.1 wt %, or 0.0005 wt % to 0.05 wt %.

23. The oxidizing agent is a peroxy compound selected from the group consisting of hydrogen peroxide, urea peroxide, performic acid, peracetic acid, propane peroxoacid, substituted or unsubstituted butane peroxoacid, hydroperoxy-acetaldehyde, potassium periodate, and ammonium peroxymonosulfate; and ferric nitrite, KClO ４ , KBrO ４ , KMnO ４ and combinations thereof; and the oxidizing agent is in the range of 0.01 wt % to 30 wt %, 0.1 wt % to 20 wt %, or 0.5 wt % to 10 wt %.

24. The activator is (1) inorganic oxide particles whose surface is coated with a transition metal selected from the group consisting of Fe, Cu, Mn, Co, Ce, and combinations thereof; (2) a soluble catalyst selected from the group consisting of iron (III) nitrate, ammonium iron (III) oxalate trihydrate, iron (III) citrate tribasic monohydrate, iron (III) acetylacetonate, and the iron (III) sodium salt hydrate of ethylenediaminetetraacetic acid; (3) a soluble catalyst selected from the group consisting of Ag, Co, Cr, 24. The polishing method according to claim 20, wherein the activator is selected from the group consisting of metal compounds having multiple oxidation states selected from the group consisting of Cu, Fe, Mo, Mn, Nb, Ni, Os, Pd, Ru, Sn, Ti, V, and combinations thereof, and the activator is in the range of 0.00001 wt % to 5.0 wt %, 0.0001 wt % to 2.0 wt %, 0.0005 wt % to 1.0 wt %, or 0.001 wt % to 0.5 wt %.

25. 25. The polishing method according to claim 20, wherein the corrosion inhibitor is selected from the group consisting of 1,2,3-triazole, 1,2,4-triazole, 1,2,3-benzotriazole, 5-methylbenzotriazole, benzotriazole, 1-hydroxybenzotriazole, 4-hydroxybenzotriazole, 3-amino-1,2,4-triazole, 4-amino-4H-1,2,4-triazole, 5-aminotriazole, benzimidazole, 2,1,3-benzothiadiazole, triazine thiol, triazine dithiol, triazine trithiol, pyrazole, imidazole, isocyanurate such as 1,3,5-tris(2-hydroxyethyl) and combinations thereof, and the corrosion inhibitor is present in an amount of less than 1.0 wt %, less than 0.5 wt %, or less than 0.25 wt %.

26. 26. The polishing method according to claim 20, wherein the pH adjuster is selected from the group consisting of: (a) nitric acid, sulfuric acid, tartaric acid, succinic acid, citric acid, malic acid, malonic acid, various fatty acids, various polycarboxylic acids, and mixtures thereof for lowering the pH; and (b) potassium hydroxide, sodium hydroxide, ammonia, tetraethylammonium hydroxide, ethylenediamine, piperazine, polyethyleneimine, modified polyethyleneimine, and mixtures thereof for raising the pH.

27. The polishing method according to any one of claims 20 to 26, wherein the composition has a pH of 1 to 14, 1 to 7, 1 to 6, or 1.5 to 4.

28. The dishing reducing agent may be selected from the group consisting of sarcosinates and related carboxylic acid compounds; hydrocarbon-substituted sarcosinates; amino acids; organic polymers and copolymers having molecules containing ethylene oxide repeat units, such as polyethylene oxide (PEO); ethoxylated surfactants; nitrogen-containing heterocycles without nitrogen-hydrogen bonds, sulfides, oxazolidines, or mixtures of functional groups in one compound; nitrogen-containing compounds having three or more carbon atoms that form alkylammonium ions; aminoalkyls having three or more carbon atoms; 28. The polishing method according to claim 20, wherein the dishing reducing agent is selected from the group consisting of: a polymeric corrosion inhibitor having a repeating group of nitrogen-containing heterocyclic rings or tertiary or quaternary nitrogen atoms; a dicationic amine compound; a cyclodextrin compound; a polyethyleneimine compound; glycolic acid; chitosan; a sugar alcohol; a polysaccharide; an alginate compound; and a sulfonic acid polymer; and combinations thereof, and the dishing reducing agent is present in an amount within the range of 0.001% to 2.0% by weight, 0.005% to 1.5% by weight, or 0.01% to 1.0% by weight.

29. 29. The polishing method according to claim 20, wherein the stabilizer is selected from the group consisting of adipic acid, phthalic acid, citric acid, malonic acid, orthophthalic acid, phosphoric acid, substituted or unsubstituted phosphonic acid, nitrile, and combinations thereof, and the stabilizer is present in an amount within the range of 0.0001 to 5 wt %, 0.00025 to 2 wt %, or 0.0005 to 1 wt %.

30. 30. The polishing method according to claim 20, wherein the abrasive is silica particles.

31. 31. The polishing method according to claim 20, wherein the chemical mechanical planarization composition comprises silica particles, iron (III) nitrate, malonic acid, hydrogen peroxide, poly(vinyl-3-ethyl-1H-imidazol-3-ium-co-tributyl-(4-vinylbenzyl)-phosphonium) bromide chloride, and water, and the pH of the composition is 1.5 to 4.

32. 32. The polishing method according to claim 20, wherein at least one surface containing tungsten has a dishing profile of less than 2000 angstroms or less than 1000 angstroms and an erosion profile of less than 2000 angstroms or less than 1000 angstroms.

33. 1. A system for chemical mechanical planarization of a semiconductor substrate having at least one surface containing tungsten, comprising: a) a polishing pad; b) a chemical-mechanical polishing composition comprising: an abrasive selected from the group consisting of inorganic oxide particles, metal oxide-coated inorganic oxide particles, organic polymer particles, metal oxide-coated organic polymer particles, and combinations thereof; activator, oxidizing agents, An additive comprising the dicationic polymer or copolymer according to any one of claims 1 to 6. water, and, if desired, corrosion inhibitors, dishing reducing agent, stabilizers, pH adjusters, a chemical-mechanical polishing composition comprising: Equipped with The at least one tungsten-containing surface is contacted with the polishing pad and the chemical mechanical planarizing composition, and the chemical mechanical planarizing composition polishes the at least one tungsten-containing surface.

34. 34. The system of claim 33, wherein the chemical mechanical planarization composition has the abrasive in the range of 0.01 wt % to 30 wt %, 0.05 wt % to 20 wt %, 0.01 wt % to 10 wt %, or 0.1 wt % to 2 wt %.

35. 35. The system of any one of claims 33-34, wherein the additive comprising the dicationic polymer or copolymer is in the range of 0.00001 wt % to 1.0 wt %, 0.0001 wt % to 0.5 wt %, 0.00025 wt % to 0.1 wt %, or 0.0005 wt % to 0.05 wt %.

36. The system of any one of claims 33 to 35, wherein the abrasive is silica particles.

37. The oxidizing agent is a peroxy compound selected from the group consisting of hydrogen peroxide, urea peroxide, performic acid, peracetic acid, propane peroxoacid, substituted or unsubstituted butane peroxoacid, hydroperoxy-acetaldehyde, potassium periodate, and ammonium peroxymonosulfate; and ferric nitrite, KClO ４ , KBrO ４ , KMnO ４ and combinations thereof; and the oxidizing agent is in the range of 0.01 wt % to 30 wt %, 0.1 wt % to 20 wt %, or 0.5 wt % to 10 wt %.

38. The activator is (1) inorganic oxide particles whose surface is coated with a transition metal selected from the group consisting of Fe, Cu, Mn, Co, Ce, and combinations thereof; (2) a soluble catalyst selected from the group consisting of iron (III) nitrate, ammonium iron (III) oxalate trihydrate, iron (III) citrate tribasic monohydrate, iron (III) acetylacetonate, and the iron (III) sodium salt hydrate of ethylenediaminetetraacetic acid; (3) a soluble catalyst selected from the group consisting of Ag, Co, Cr, 38. The system of any one of claims 33-37, wherein the activator is selected from the group consisting of metal compounds having multiple oxidation states selected from the group consisting of Cu, Fe, Mo, Mn, Nb, Ni, Os, Pd, Ru, Sn, Ti, V, and combinations thereof, and the activator is in the range of 0.00001 wt.% to 5.0 wt.%, 0.0001 wt.% to 2.0 wt.%, 0.0005 wt.% to 1.0 wt.%, or 0.001 wt.% to 0.5 wt.%.

39. 39. The system of any one of claims 33-38, wherein the corrosion inhibitor is selected from the group consisting of 1,2,3-triazole, 1,2,4-triazole, 1,2,3-benzotriazole, 5-methylbenzotriazole, benzotriazole, 1-hydroxybenzotriazole, 4-hydroxybenzotriazole, 3-amino-1,2,4-triazole, 4-amino-4H-1,2,4-triazole, 5-aminotriazole, benzimidazole, 2,1,3-benzothiadiazole, triazine thiols, triazine dithiols, and triazine trithiols, pyrazoles, imidazoles, isocyanurates such as 1,3,5-tris(2-hydroxyethyl) and combinations thereof, and the corrosion inhibitor is in the range of less than 1.0 wt%, less than 0.5 wt%, or less than 0.25 wt%.

40. 40. The system of any one of claims 33-39, wherein the pH adjuster is selected from the group consisting of: (a) nitric acid, sulfuric acid, tartaric acid, succinic acid, citric acid, malic acid, malonic acid, various fatty acids, various polycarboxylic acids, and mixtures thereof for lowering the pH; and (b) potassium hydroxide, sodium hydroxide, ammonia, tetraethylammonium hydroxide, ethylenediamine, piperazine, polyethyleneimine, modified polyethyleneimine, and mixtures thereof for raising the pH.

41. 41. The system of any one of claims 33 to 40, wherein the pH of the composition is 1 to 14, 1 to 7, 1 to 6, or 1.5 to 4.

42. The dishing reducing agent may be selected from the group consisting of sarcosinates and related carboxylic acid compounds; hydrocarbon-substituted sarcosinates; amino acids; organic polymers and copolymers having molecules containing ethylene oxide repeat units, such as polyethylene oxide (PEO); ethoxylated surfactants; nitrogen-containing heterocycles without nitrogen-hydrogen bonds, sulfides, oxazolidines, or mixtures of functional groups in one compound; nitrogen-containing compounds having three or more carbon atoms that form alkylammonium ions; aminoalkyls having three or more carbon atoms; 42. The system of any one of claims 33-41, wherein the dishing reducing agent is selected from the group consisting of: a polymeric corrosion inhibitor comprising a repeating group of nitrogen-containing heterocyclic rings or tertiary or quaternary nitrogen atoms; a dicationic amine compound; a cyclodextrin compound; a polyethyleneimine compound; glycolic acid; chitosan; a sugar alcohol; a polysaccharide; an alginate compound; and a sulfonic acid polymer; and combinations thereof, and the dishing reducing agent is in the range of 0.001% to 2.0% by weight, 0.005% to 1.5% by weight, or 0.01% to 1.0% by weight.

43. 43. The system of any one of claims 33-42, wherein the stabilizing agent is selected from the group consisting of adipic acid, phthalic acid, citric acid, malonic acid, orthophthalic acid, phosphoric acid, substituted or unsubstituted phosphonic acids, nitriles, and combinations thereof, and the stabilizing agent is in the range of 0.0001 to 5 wt%, 0.00025 to 2 wt%, or 0.0005 to 1 wt%.

44. 44. The system of any one of claims 33 to 43, wherein the chemical mechanical planarization composition comprises silica particles, iron(III) nitrate, malonic acid, hydrogen peroxide, poly(vinyl-3-ethyl-1H-imidazol-3-ium-co-tributyl-(4-vinylbenzyl)-phosphonium) bromide chloride, and water, and wherein the pH of the composition is from 1.5 to 4.

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