Composition for inhibiting tungsten etching

Abstract

The present invention relates to compositions and methods for inhibiting etching. In particular, the present invention relates to compositions and methods for inhibiting tungsten etching.

Description

Technical Field

[0001] The present invention relates to compositions and methods for inhibiting etching. In particular, the present invention relates to compositions and methods for inhibiting tungsten etching.

[0002] background

[0003] The integrated circuits that form semiconductor devices are composed of active devices that are chemically and physically connected to a substrate and interconnected using multilayer interconnects. Typically, the multilayer interconnects form a functional circuit and include a first metal layer, an interlayer dielectric layer, and an optional third metal layer. As each layer is formed, it is planarized so that subsequent layers are formed on the newly formed layer. In the semiconductor industry, chemical mechanical polishing (CMP) is a well-known technique used in the manufacture of advanced photonic, microelectromechanical, and microelectronic materials and devices, such as semiconductor wafers.

[0004] CMP utilizes the interaction of chemical and mechanical action to achieve flatness of the surface to be polished. The chemical action is provided by a chemical composition (also referred to as a CMP composition or CMP slurry). The mechanical action is typically provided by a polishing pad, which is typically pressed against the surface to be polished and mounted on a moving platen. In a typical CMP process, a rotating wafer holder brings the wafer to be polished into contact with the polishing pad. The CMP composition is typically applied between the wafer to be polished and the polishing pad.

[0005] With the continuous reduction in feature sizes in ultra-large-scale integrated circuit (ULSI) technology, copper interconnects are becoming increasingly smaller. To reduce RC delay—the delay in signal speed through circuit wiring due to resistance (R) and capacitance (C)—the thickness of barrier or adhesion layers in copper interconnects has become increasingly thinner. The traditional copper barrier / adhesion layer stack of Ta / TaN is no longer suitable due to Ta's relatively high resistivity and the inability of copper to be directly electroplated onto Ta. The use of tungsten as a conductive material to form interconnects is increasing. In a typical manufacturing process, CMP (chemical polishing) is used to reduce the thickness of the tungsten capping layer until a flat surface is achieved, exposing the elevated silicon dioxide portions and forming the dielectric layer. Typically, CMP compositions used to polish tungsten-containing substrates contain a compound capable of etching tungsten. The tungsten-etching compound converts the tungsten into a soft oxide film that can be removed by mechanical abrasion. During the polishing step of the CMP process, the tungsten capping layer is removed to achieve substrate planarization. However, during this process, the tungsten can be undesirably eroded due to a combination of static etching and the mechanical action of the abrasive, resulting in dishing defects or erosion.

[0006] Compositions comprising tungsten etching inhibitors are known in the prior art and are described, for example, in the following references.

[0007] US 6,273,786 B1 describes methods and compositions comprising tungsten corrosion inhibitors including phosphates, polyphosphates and silicates, in particular potassium hypophosphite and potassium silicate, for protecting tungsten.

[0008] US Pat. No. 6,083,419 A describes a chemical mechanical polishing composition comprising a compound capable of etching tungsten and at least one tungsten etching inhibitor, wherein the tungsten etching inhibitor is a compound comprising at least one functional group selected from a nitrogen-containing heterocycle having no nitrogen-hydrogen bond, a sulfide, an oxazolidine, or a mixture of functional groups in one compound.

[0009] US 9,303,188 B2 discloses a chemical mechanical polishing composition comprising an amine compound that inhibits tungsten etching.

[0010] The methods and compositions disclosed in the prior art have limitations. In the methods and compositions disclosed in the prior art, the inhibitors are not always effective in preventing tungsten corrosion within the trench. Furthermore, the use of high concentrations of inhibitors known in the prior art can reduce the polishing rate of substrates containing tungsten layers to unacceptably low levels. Therefore, there is a need for improved compositions and methods for inhibiting tungsten etching, as well as compositions that can provide reduced tungsten corrosion during CMP processes.

[0011] It is therefore an object of the present invention to provide an improved composition and an improved method for inhibiting tungsten etching.

[0012] Overview

[0013] It has surprisingly been discovered that the compositions of the present invention described below provide low static etch rates for tungsten and inhibit tungsten etching.

[0014] Therefore, in one aspect of the present invention, there is provided a composition for inhibiting tungsten etching, comprising:

[0015] (A) at least one inorganic abrasive particle;

[0016] (B) at least one corrosion inhibitor selected from the group consisting of methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts; and

[0017] (C) an aqueous medium; and

[0018] The pH value of the composition is ≥5.0 to ≤11.0.

[0019] In another aspect, the present invention relates to a method for manufacturing a semiconductor device comprising chemically mechanically polishing a substrate (S) used in the semiconductor industry in the presence of a composition as described herein, wherein the substrate (S) comprises:

[0020] (i) tungsten, and / or

[0021] (ii) Tungsten alloy.

[0022] In another aspect, the present invention relates to the use of the compositions described herein for inhibiting tungsten etching.

[0023] The present invention is associated with at least one of the following advantages:

[0024] (1) The compositions and methods of the present invention exhibit improved performance in inhibiting etching, particularly tungsten etching.

[0025] (2) The compositions and methods of the present invention prevent tungsten corrosion during chemical mechanical polishing of tungsten-containing substrates.

[0026] (3) The compositions of the present invention provide stable formulations or dispersions in which phase separation does not occur.

[0027] (4) The method of the present invention is easy to apply and requires as few steps as possible.

[0028] (5) The compositions and methods of the present invention do not affect the polishing rate of the substrate during chemical mechanical polishing.

[0029] Those skilled in the art will appreciate other objects, advantages and applications of the present invention from the following detailed description.

[0030] Details

[0031] The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding technical field, background, summary or the following detailed description.

[0032] As used herein, the terms "comprising" and "including" are synonymous with "containing" and are inclusive or open-ended and do not exclude additional undescribed members, elements, or method steps. It should be understood that the terms "comprising" and "including" include the term "consisting of."

[0033] In addition, the terms "(a)", "(b)", "(c)", "(d)", etc. in the specification and claims are used to distinguish similar elements and not necessarily to describe a sequential or chronological order. It is understood that the terms so used are interchangeable where appropriate and that the embodiments of the invention described herein are capable of operation in sequences other than those described or illustrated herein. Where the terms "(A)", "(B)" and "(C)" or "(a)", "(b)", "(c)", "(d)", "(i)", "(ii)", etc. refer to steps of a method or use or an assay, there is no temporal or temporal correlation between the steps, i.e., the steps may be performed simultaneously or there may be time intervals of seconds, minutes, hours, days, weeks, months or even years between the steps, unless otherwise indicated in the application as above or below.

[0034] In the following paragraphs, different aspects of the present invention are defined in more detail. Each aspect so defined can be combined with any other one or more aspects, unless explicitly indicated otherwise. In particular, any feature indicated as preferred or advantageous can be combined with any other one or more features indicated as preferred or advantageous.

[0035] References throughout this specification to "one embodiment" or "an embodiment" or "a preferred embodiment" mean that a particular feature, structure, or characteristic described with respect to that embodiment is included in at least one embodiment of the present invention. Thus, the phrases "in one embodiment" or "in an embodiment" or "in a preferred embodiment" appearing in various places throughout this specification do not necessarily all refer to the same embodiment, but may refer to the same embodiment. Furthermore, as will be appreciated by those skilled in the art from this disclosure, features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Furthermore, as will be appreciated by those skilled in the art, although some embodiments described herein include some features and not other features included in other embodiments, combinations of features from different embodiments are intended to fall within the scope of the subject matter and to form different embodiments. For example, in the appended claims, any of the claimed embodiments may be used in any combination.

[0036] Furthermore, ranges defined throughout this specification are also inclusive, i.e., a range of 1-10 means that both 1 and 10 are included within the range. For the avoidance of doubt, applicants are entitled to any equivalents under applicable law.

[0037] For purposes of the present invention, the "weight %" used herein is relative to the total weight of the coating composition. In addition, as described below, the sum of the weight % of all compounds in each component is 100 weight %.

[0038] For the purposes of this invention, corrosion inhibitors are defined as chemical compounds that form a protective molecular layer on metal surfaces.

[0039] For the purposes of this invention, chelating agents are defined as chemical compounds that form soluble complex molecules with certain metal ions, thereby inactivating the ions so that they cannot normally react with other elements or ions to produce precipitation or scaling.

[0040] For the purposes of the present invention, a low-k material is a material having a k value (dielectric constant) of less than 3.5, preferably less than 3.0, more preferably less than 2.7. An ultra-low-k material is a material having a k value (dielectric constant) of less than 2.4.

[0041] For the purposes of the present invention, colloidal inorganic particles are inorganic particles prepared by wet precipitation; pyrolytic inorganic particles are particles prepared by high temperature flame hydrolysis, for example by treating a metal chloride precursor with hydrogen in the presence of oxygen, for example using method.

[0042] For the purposes of the present invention, "colloidal silica" refers to silica prepared by the polycondensation of Si(OH)4. The precursor Si(OH)4 can be obtained, for example, by the hydrolysis of high-purity alkoxysilanes or by the acidification of aqueous silicate solutions. The colloidal silica can be prepared according to U.S. Patent No. 5,230,833 or can be obtained as any of a variety of commercially available products, such as PL-1, PL-2, and PL-3 products, and Nalco 1050, 2327, and 2329 products, and other similar products available from DuPont, Bayer, Applied Research, Nissan Chemical, Nyacol, and Clariant.

[0043] For the purposes of the present invention, the average particle size is defined as the particle size distribution of the inorganic abrasive particles (A) in the aqueous medium (H). 50 value.

[0044] For the purposes of the present invention, the average particle size is measured, for example, using dynamic light scattering (DLS) or static light scattering (SLS) methods. These and other methods are well known in the art, see, for example, Kuntzsch, Timo; Witnik, Ulrike; Hollatz, Michael Stintz; Ripperger, Siegfried; Characterization of Slurries Used for Chemical-Mechanical Polishing (CMP) in the Semiconductor Industry, Chem. Eng. Technol, 26 (2003), Vol. 12, p. 1235.

[0045] For the purposes of the present invention, for dynamic light scattering (DLS), a Horiba LB-550V (DLS, dynamic light scattering measurement) or any other such instrument is generally used. This technique measures the hydrodynamic diameter of the particles when they scatter a laser light source (λ=650 nm), detected at an angle of 90° or 173° relative to the incident light. The variations in the scattered light intensity are due to the random Brownian motion of the particles in the incident light beam and are monitored as a function of time. The autocorrelation function performed by the instrument as a function of the delay time is used to extract the decay constant; smaller particles move through the incident light beam at a higher speed and correspond to a faster decay.

[0046] In the present invention, the attenuation constant and the diffusion coefficient D of the inorganic abrasive particles are t is proportional to and is used to calculate the particle size according to the Stokes-Einstein equation:

[0047]

[0048] The assumption is that the suspended particles (1) have a spherical morphology and (2) are uniformly dispersed (i.e., not agglomerated) throughout the aqueous medium. This relationship is expected to hold true for particle dispersions containing less than 1% by weight solids, since there is no significant deviation from the viscosity of the aqueous dispersant, where η = 0.96 mPa·s (at T = 22°C). The particle size distribution of pyrolytic or colloidal inorganic particle dispersions is typically measured in plastic cuvettes at a solids concentration of 0.1-1.0% and, if necessary, diluted with dispersion medium or ultrapure water.

[0049] For the purposes of the present invention, the BET surface area of ​​the inorganic abrasive particles is determined in accordance with DIN ISO 9277:2010-09.

[0050] For the purposes of the present invention, an oxidizing agent is defined as a chemical compound which can oxidize the substrate to be polished or one of its layers.

[0051] For the purposes of the present invention, a pH adjusting agent is defined as a compound which is added to adjust the pH to the desired value.

[0052] Insofar as the present invention is concerned, the disclosed measurement techniques are well known to a person skilled in the art and therefore do not limit the present invention.

[0053] In one aspect of the present invention, a composition for inhibiting tungsten is provided, comprising the following components:

[0054] (A) at least one inorganic abrasive particle;

[0055] (B) at least one corrosion inhibitor selected from the group consisting of methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts; and

[0056] (C) an aqueous medium; and

[0057] The pH value of the composition is ≥5.0 to ≤11.0.

[0058] The composition comprises components (A), (B) and (C) and other components as described below.

[0059] In an embodiment of the present invention, the at least one inorganic abrasive particle (A) is selected from the group consisting of metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamond, organic hybrid particles, inorganic hybrid particles and silicon dioxide.

[0060] For the purposes of the present invention, there are no particular restrictions on the chemical nature of the at least one inorganic abrasive particle (A). The at least one inorganic abrasive particle (A) may have the same chemical nature or may be a mixture of particles of different chemical natures. For the purposes of the present invention, inorganic abrasive particles (A) having the same chemical nature are preferred. The inorganic abrasive particles (A) are selected from metal oxides, metal nitrides, metal carbides, including metalloids, metalloid oxides or carbides, silicides, borides, ceramics, diamond, organic / inorganic hybrid particles, silica, and any mixture of inorganic particles.

[0061] In the present invention, the at least one inorganic abrasive particle (A) may be:

[0062] ●A kind of colloidal inorganic particles,

[0063] ●A kind of pyrolysis inorganic particles,

[0064] • Mixtures of different types of colloidal and / or pyrogenic inorganic particles.

[0065] For the purposes of the present invention, the at least one inorganic particle (A) is selected from colloidal or pyrogenic inorganic particles or mixtures thereof. Among them, oxides and carbides of metals or metalloids are preferred. For the purposes of the present invention, the at least one inorganic particle (A) is preferably selected from aluminum oxide, cerium dioxide, copper oxide, iron oxide, nickel oxide, manganese oxide, silicon dioxide, silicon nitride, silicon carbide, tin oxide, titanium dioxide, titanium carbide, tungsten oxide, yttrium oxide, zirconium oxide or mixtures or composites thereof. For the purposes of the present invention, the at least one inorganic particle (A) is more preferably selected from aluminum oxide, cerium dioxide, silicon dioxide, titanium dioxide, zirconium oxide or mixtures or composites thereof. In particular, the at least one inorganic abrasive particle (A) is silicon dioxide. For the purposes of the present invention, the at least one inorganic particle (A) is most preferably colloidal silica particles.

[0066] In another embodiment of the present invention, the concentration of the at least one inorganic abrasive particle (A) is ≧0.01 wt. % to ≦10.0 wt. %, based on the total weight of the composition.

[0067] For the purposes of the present invention, the concentration of the at least one inorganic abrasive particle (A) is not more than 10.0 wt. %, preferably not more than 5.0 wt. %, in particular not more than 3.0 wt. %, for example not more than 2.0 wt. %, most preferably not more than 1.8 wt. %, and in particular not more than 1.5 wt. %, based on the total weight of the composition. For the purposes of the present invention, the concentration of the at least one inorganic abrasive particle (A) is preferably at least 0.01 wt. %, more preferably at least 0.1 wt. %, most preferably at least 0.2 wt. %, and in particular at least 0.3 wt. %, based on the total weight of the composition. For the purposes of the present invention, the concentration of the at least one inorganic abrasive particle (A) is more preferably from ≥ 0.3 wt. % to ≤ 1.2 wt. %, based on the total weight of the composition.

[0068] In the present invention, the at least one inorganic abrasive particle (A) can be included in the composition in various particle size distributions. The particle size distribution of the at least one inorganic abrasive particle (A) can be unimodal or multimodal. In the case of a multimodal particle size distribution, a bimodal particle size distribution is generally preferred. In the present invention, the inorganic abrasive particle (A) preferably has a unimodal particle size distribution. The particle size distribution of the inorganic abrasive particle (A) is not particularly limited.

[0069] In a preferred embodiment of the present invention, the at least one inorganic abrasive particle (A) has an average particle size of ≧1 nm to ≦1000 nm, as determined by dynamic light scattering techniques.

[0070] The average particle size of the at least one inorganic abrasive particle (A) can vary within a wide range. For the purposes of the present invention, the average particle size of the at least one inorganic abrasive particle (A) is preferably ≥1 nm to ≤1000 nm, preferably ≥10 nm to ≤400 nm, more preferably ≥20 nm to ≤200 nm, more preferably ≥25 nm to ≤180 nm, most preferably ≥30 nm to ≤170 nm, particularly preferably ≥40 nm to ≤160 nm, and most preferably ≥45 nm to ≤150 nm, in each case measured by dynamic light scattering using an instrument such as the High Performance Particle Sizer (HPPS) from Malvern Instruments, Ltd. or the Horiba LB550.

[0071] The BET surface area of ​​the at least one inorganic abrasive particle (A) can vary within a wide range. For the purposes of the present invention, the BET surface area of ​​the at least one inorganic abrasive particle (A) is preferably ≥ 1 m 2 / g to ≤500m 2 / g, more preferably ≥5m 2 / g to ≤250m 2 / g, most preferably ≥10m 2 / g to ≤100m 2 / g, particularly preferably ≥20m 2 / g to ≤95m 2 / g, and most preferably ≥25m 2 / g to ≤92m 2 / g, determined in each case according to ISO 9277:2010-09.

[0072] For the purposes of the present invention, the at least one inorganic abrasive particle (A) can have various shapes. Thus, the particle (A) can have one or essentially only one shape. However, the particle (A) can also have different shapes. For example, there can be two particles (A) of different shapes. For example, (A) can have the shape of an agglomerate, a cube, a cube with beveled edges, an octahedron, an icosahedron, a cocoon, a nodule, or a sphere, with or without protrusions or depressions. For the purposes of the present invention, the inorganic abrasive particles (A) are preferably essentially spherical, wherein they generally have protrusions or depressions.

[0073] For the purposes of the present invention, the at least one inorganic abrasive particle (A) is preferably cocoon-shaped. The cocoons may or may not have protrusions or depressions. Cocoon-shaped particles are preferably particles having a minor axis of ≥10 nm to ≤200 nm, and preferably a major axis / minor axis ratio of ≥1.4 to ≤2.2, more preferably ≥1.6 to ≤2.0. Preferably, they have an average shape factor of ≥0.7 to ≤0.97, more preferably ≥0.77 to ≤0.92, preferably an average sphericity of ≥0.4 to ≤0.9, more preferably ≥0.5 to ≤0.7, and preferably an average equivalent circular diameter of ≥41 nm to ≤66 nm, more preferably ≥48 nm to ≤60 nm, in each case determined by transmission electron microscopy and scanning electron microscopy.

[0074] In the context of the present invention, the determination of the shape factor, sphericity and equivalent circular diameter of cocoon-shaped particles is explained below. The shape factor provides information about the shape and concavity of the individual particles and can be calculated according to the following formula:

[0075] Shape factor = 4π(area / perimeter²)

[0076] The shape factor of a spherical particle without indentations is 1. As the number of indentations increases, the value of the shape factor decreases. Sphericity gives information on the average elongation of individual particles using moments and can be calculated according to the following formula, where M is the center of gravity of each particle:

[0077] Sphericity = (Mxx-Myy)-[4Mxy2+(Myy-Mxx)2]0.5 / (Mxx-Myy)+

[0078] [4Mxy2+(Myy-Mxx)2]0.5

[0079] Elongation = (1 / sphericity) 0.5

[0080] in:

[0081] Mxx=Σ(xx average)2 / N

[0082] Myy=Σ(yy average)2 / N

[0083] Mxy=Σ[(average of xx)*(average of yy)] / N

[0084] N: The number of pixels that form the image of each particle

[0085] x, y: pixel coordinates

[0086] x average: the average value of the x coordinates of the N pixels that form the particle image

[0087] y average: the average value of the y coordinates of the N pixels that form the particle image

[0088] Spherical particles have a sphericity of 1. As particles are elongated, the sphericity value decreases. The equivalent circular diameter (hereinafter also abbreviated as ECD) of an individual non-circular particle provides information about the diameter of a circle with the same area as the respective non-circular particle. The average shape factor, average sphericity, and average ECD are the arithmetic means of the respective properties relative to the number of particles analyzed.

[0089] For the purposes of the present invention, the procedure for particle shape characterization is as follows. An aqueous dispersion of cocoon-shaped silica particles with a solid content of 20 wt % is dispersed on carbon foil and dried. The dried dispersion is analyzed by using energy-filtered transmission electron microscopy (EF-TEM) (120 kV) and scanning electron microscopy secondary electron imaging (SEM-SE) (5 kV). EF-TEM images with a resolution of 2k, 16 bits, and 0.6851 nm / pixel are used for analysis. The images are binary encoded using a threshold after noise suppression. Subsequently, the particles are manually separated. Overlapping and edge particles are distinguished and not used for analysis. The ECD, shape factor, and sphericity as defined above are calculated and statistically classified.

[0090] For the purposes of the present invention, representative examples of cocoon-like particles include, but are not limited to, those produced by Fuso Chemical Corporation having an average primary particle size (d1) of 35 nm and an average secondary particle size (d2) of 70 nm. PL-3.

[0091] In a more preferred embodiment of the present invention, the at least one inorganic abrasive particle (A) is a silica particle having an average primary particle size (d1) of 35 nm and an average secondary particle size (d2) of 70 nm.

[0092] In the most preferred embodiment of the present invention, the at least one inorganic abrasive particle (A) is colloidal silica particles having an average primary particle size (d1) of 35 nm and an average secondary particle size (d2) of 70 nm.

[0093] In another most preferred embodiment of the present invention, the at least one inorganic abrasive particle (A) is cocoon-shaped silica particles having an average primary particle size (d1) of 35 nm and an average secondary particle size (d2) of 70 nm.

[0094] The composition further comprises at least one corrosion inhibitor (B) selected from methylbenzylthionium, methylbenzylthionium salt, benzylthionium and benzylthionium salt. The corrosion inhibitor (B) is different from components (A), (C), (D), (E) and (F).

[0095] In an embodiment of the present invention, the at least one corrosion inhibitor (B) is benzethonium.

[0096] In a preferred embodiment of the present invention, the benzethonium salt is selected from the group consisting of benzethonium fluoride, benzethonium chloride, benzethonium bromide, benzethonium hydroxide and benzethonium citrate.

[0097] In another preferred embodiment of the present invention, the methylbenzethonium salt is selected from the group consisting of methylbenzethonium fluoride, methylbenzethonium chloride, methylbenzethonium bromide, methylbenzethonium hydroxide and methylbenzethonium citrate.

[0098] In an embodiment of the present invention, the at least one corrosion inhibitor (B) is present in an amount of ≧0.0001 wt. % to ≦0.009 wt. %, based on the total weight of the composition.

[0099] For the purposes of the present invention, the at least one corrosion inhibitor (B) is preferably present in an amount of not more than 0.009 wt. %, more preferably not more than 0.08 wt. %, most preferably not more than 0.07 wt. %, and most preferably not more than 0.06 wt. %, based on the total weight of the composition. The amount of (B) is preferably at least 0.0001 wt. %, more preferably at least 0.0002 wt. %, most preferably at least 0.0005 wt. %, and particularly preferably at least 0.001 wt. %, based on the total weight of the composition. For the purposes of the present invention, the concentration of the at least one corrosion inhibitor (B) is more preferably from ≥ 0.0005 wt. % to ≤ 0.009 wt. %, and most preferably from ≥ 0.001 wt. % to ≤ 0.006 wt. %, based on the total weight of the composition.

[0100] The composition further comprises an aqueous medium (C). The aqueous medium (C) may be one aqueous medium or a mixture of different aqueous media.

[0101] For the purposes of the present invention, the aqueous medium (C) may be any medium comprising water. Preferably, the aqueous medium (C) is a mixture of water and a water-miscible organic solvent. Representative examples of organic solvents include, but are not limited to, C1-C3 alcohols, alkylene glycols, and alkylene glycol derivatives. More preferably, the aqueous medium (C) is water. In an embodiment of the present invention, the aqueous medium (C) is deionized water.

[0102] For purposes of the present invention, if the amounts of components other than (C) together constitute y wt % of the composition, then the amount of (C) constitutes (100-y) wt % of the composition.

[0103] For the purposes of the present invention, the amount of aqueous medium (C) in the composition is not more than 99.9% by weight, more preferably not more than 99.6% by weight, most preferably not more than 99% by weight, particularly preferably not more than 98% by weight, in particular not more than 97% by weight, for example not more than 95% by weight, based on the total weight of the composition. For the purposes of the present invention, the amount of aqueous medium (C) in the composition is at least 60% by weight, more preferably at least 70% by weight, most preferably at least 80% by weight, particularly preferably at least 85% by weight, in particular at least 90% by weight, for example at least 93% by weight, based on the total weight of the composition.

[0104] The properties of the composition may depend on the pH of the respective composition. For the purposes of the present invention, the pH value of the composition is preferably not greater than 11.0, more preferably not greater than 10.5, most preferably not greater than 10.0, particularly preferably not greater than 9.5, and most preferably not greater than 9.0. For the purposes of the present invention, the pH value of the composition is preferably at least 5.0, more preferably at least 5.5, and most preferably at least 6.0. For the purposes of the present invention, the pH value of the composition is preferably ≥5.0 to ≤11.0, preferably ≥5.0 to ≤10.0, more preferably ≥5.0 to ≤9.5, most preferably ≥5.5 to ≤9.5, and particularly preferably ≥6.0 to ≤9.0.

[0105] In an embodiment of the present invention, the pH value of the composition is ≥5.0 to ≤10.0.

[0106] In a preferred embodiment of the present invention, the pH value of the composition is ≥6.0 to ≤9.0.

[0107] The composition further comprises at least one corrosion inhibitor (D). The corrosion inhibitor (D) is different from components (A), (B), (C), (E) and (F).

[0108] In an embodiment of the present invention, the at least one corrosion inhibitor (D) is selected from polyacrylamides and polyacrylamide copolymers.

[0109] In a preferred embodiment of the present invention, the polyacrylamide copolymer is an anionic or nonionic polyacrylamide copolymer. For the purposes of the present invention, the polyacrylamide copolymer is preferably not selected from cationic polyacrylamide copolymers. The use of cationic polyacrylamide copolymers in the composition may lead to flocculation and instability. In a more preferred embodiment of the present invention, the polyacrylamide copolymer is a nonionic polyacrylamide copolymer.

[0110] In a particularly preferred embodiment of the present invention, the polyacrylamide is a homopolymer of polyacrylamide.

[0111] In an embodiment of the present invention, the at least one corrosion inhibitor (D) is present in an amount of ≧0.001 wt. % to ≦0.5 wt. %, based on the total weight of the composition.

[0112] For the purposes of the present invention, the at least one corrosion inhibitor (D) is preferably present in an amount of not more than 0.5 wt. %, more preferably not more than 0.4 wt. %, most preferably not more than 0.3 wt. %, and most preferably not more than 0.2 wt. %, based on the total weight of the composition. The amount of (D) is preferably at least 0.001 wt. %, more preferably at least 0.002 wt. %, most preferably at least 0.001 wt. %, and particularly preferably at least 0.01 wt. %, based on the total weight of the composition. For the purposes of the present invention, the concentration of the at least one corrosion inhibitor (D) is more preferably from ≥ 0.01 wt. % to ≤ 0.3 wt. %, and most preferably from ≥ 0.01 wt. % to ≤ 0.2 wt. %, based on the total weight of the composition.

[0113] In a preferred embodiment of the present invention, the weight average molecular weight of the at least one corrosion inhibitor (D) is from ≥5000 g / mol to ≤50,000 g / mol, as determined by gel permeation chromatography. In a more preferred embodiment of the present invention, the weight average molecular weight of the at least one corrosion inhibitor (D) is from ≥5000 g / mol to ≤40,000 g / mol, as determined by gel permeation chromatography. In a most preferred embodiment of the present invention, the weight average molecular weight of the at least one corrosion inhibitor (D) is from ≥7500 g / mol to ≤15,000 g / mol, as determined by gel permeation chromatography.

[0114] The composition further comprises at least one oxidizing agent (E). The oxidizing agent is different from components (A), (B), (C), (D) and (F).

[0115] In an embodiment of the present invention, the at least one oxidizing agent (E) is selected from the group consisting of organic peroxides, inorganic peroxides, nitrates, persulfates, iodates, periodic acid, periodates, permanganates, perchloric acid, perchlorates, bromic acid and bromates.

[0116] In a preferred embodiment of the present invention, the at least one oxidizing agent (E) is selected from peroxides and ferric nitrate. In a more preferred embodiment of the present invention, the at least one oxidizing agent (E) is hydrogen peroxide.

[0117] In an embodiment of the present invention, the at least one oxidizing agent (E) is present in an amount of ≧0.01 wt.-% to ≦1.0 wt.-%, based on the total weight of the composition.

[0118] For the purposes of the present invention, the concentration of the at least one oxidizing agent (E) is not more than 1.0% by weight, more preferably not more than 0.9% by weight, more preferably not more than 0.8% by weight, most preferably not more than 0.5% by weight, in each case based on the total weight of the composition. For the purposes of the present invention, the concentration of the at least one oxidizing agent (E) is at least 0.01% by weight, more preferably at least 0.05% by weight, most preferably at least 0.1% by weight, in each case based on the total weight of the composition.

[0119] For the purposes of the present invention, the concentration of hydrogen peroxide as oxidizing agent is preferably ≥0.01% by weight to ≤1.0% by weight, more preferably ≥0.05% by weight to ≤1.0% by weight, most preferably ≥0.05% by weight to ≤0.5% by weight, particularly preferably ≥0.01% by weight to ≤0.1% by weight, in each case based on the total weight of the composition.

[0120] The composition of the present invention may further optionally comprise at least one pH adjuster (F). The at least one pH adjuster (F) is different from components (A), (B), (C), (D) and (E).

[0121] In the context of the present invention, the at least one pH adjusting agent (E) is selected from the group consisting of inorganic acids, carboxylic acids, amine bases, alkali metal hydroxides, and ammonium hydroxide (including tetraalkylammonium hydroxide). Preferably, the at least one pH adjusting agent (E) is selected from the group consisting of nitric acid, sulfuric acid, phosphorous acid, phosphoric acid, ammonia, sodium hydroxide, and potassium hydroxide. In particular, the pH adjusting agent (E) is potassium hydroxide.

[0122] For the purposes of the present invention, the amount of the at least one pH adjusting agent (E) is preferably not more than 10 wt. %, more preferably not more than 2 wt. %, most preferably not more than 0.5 wt. %, in particular not more than 0.1 wt. %, for example not more than 0.05 wt. %, based on the total weight of the composition. For the purposes of the present invention, the amount of the at least one pH adjusting agent (E) is preferably at least 0.0005 wt. %, more preferably at least 0.005 wt. %, most preferably at least 0.025 wt. %, in particular at least 0.1 wt. %, for example at least 0.4 wt. %, based on the total weight of the composition.

[0123] In the context of the present invention, the composition may optionally include additives. In the context of the present invention, representative examples of additives include, but are not limited to, stabilizers. Additives commonly used in compositions are, for example, used to stabilize dispersions.

[0124] For the purposes of the present invention, the concentration of the additive is no greater than 10.0 wt %, more preferably no greater than 1.0 wt %, most preferably no greater than 0.1 wt %, for example no greater than 0.01 wt %, based on the total weight of the composition. For the purposes of the present invention, the concentration of the additive is at least 0.0001 wt %, more preferably at least 0.001 wt %, most preferably at least 0.01 wt %, for example at least 0.1 wt %, based on the total weight of the composition.

[0125] A preferred embodiment of the present invention relates to a composition comprising the following components:

[0126] (A) at least one inorganic abrasive particle;

[0127] (B) at least one corrosion inhibitor selected from the group consisting of methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0128] (C) an aqueous medium; and

[0129] (D) at least one corrosion inhibitor selected from polyacrylamide and polyacrylamide copolymers; and

[0130] The pH value of the composition is ≥5.0 to ≤11.0.

[0131] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0132] (A) at least one inorganic abrasive particle;

[0133] (B) at least one corrosion inhibitor selected from the group consisting of methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0134] (C) an aqueous medium; and

[0135] (D) at least one corrosion inhibitor selected from polyacrylamide and polyacrylamide copolymers; and

[0136] The pH value of the composition is ≥6.0 to ≤10.0.

[0137] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0138] (A) at least one inorganic abrasive particle;

[0139] (B) at least one corrosion inhibitor selected from the group consisting of methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0140] (C) aqueous medium;

[0141] (D) at least one corrosion inhibitor selected from polyacrylamide and polyacrylamide copolymers; and

[0142] (E) at least one oxidizing agent selected from the group consisting of organic peroxides, inorganic peroxides, persulfates, iodates, potassium hydroxide, ferric nitrate, periodic acid, periodates, permanganates, perchloric acid, perchlorates, phosphoric acid, bromic acid, and bromates; and

[0143] The pH value of the composition is ≥5.0 to ≤10.0.

[0144] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0145] (A) at least one inorganic abrasive particle;

[0146] (B) at least one corrosion inhibitor selected from the group consisting of methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0147] (C) aqueous medium;

[0148] (D) at least one corrosion inhibitor selected from polyacrylamide and polyacrylamide copolymers;

[0149] (E) at least one oxidizing agent selected from the group consisting of organic peroxides, inorganic peroxides, persulfates, iodates, potassium hydroxide, ferric nitrate, periodic acid, periodates, permanganates, perchloric acid, perchlorates, phosphoric acid, bromic acid, and bromates; and

[0150] The pH value of the composition is ≥5.0 to ≤10.0.

[0151] A preferred embodiment of the present invention relates to a composition comprising the following components:

[0152] (A) ≥0.01 wt % and ≤10.0 wt % of at least one inorganic abrasive particle;

[0153] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts; and

[0154] (C) aqueous medium;

[0155] wherein the pH value of the composition is ≥5.0 to ≤10.0; and

[0156] The percentages by weight are in each case based on the total weight of the composition.

[0157] A preferred embodiment of the present invention relates to a composition comprising the following components:

[0158] (A) ≥0.01 wt % to ≤10.0 wt % of at least one inorganic abrasive particle;

[0159] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts; and

[0160] (C) aqueous medium;

[0161] wherein the pH value of the composition is ≥5.5 to ≤9.5; and

[0162] The percentages by weight are in each case based on the total weight of the composition.

[0163] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0164] (A) ≥0.01 wt % and ≤10.0 wt % of at least one inorganic abrasive particle;

[0165] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0166] (C) an aqueous medium; and

[0167] (D) ≥ 0.001 wt % to ≤ 0.5 wt % of at least one corrosion inhibitor selected from polyacrylamide and polyacrylamide copolymers;

[0168] wherein the pH value of the composition is ≥6.0 to ≤10.0; and

[0169] The percentages by weight are in each case based on the total weight of the composition.

[0170] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0171] (A) ≥0.01 wt % to ≤10.0 wt % of at least one inorganic abrasive particle;

[0172] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0173] (C) an aqueous medium; and

[0174] (D) ≥ 0.001 wt % to ≤ 0.5 wt % of at least one corrosion inhibitor selected from polyacrylamide and polyacrylamide copolymers;

[0175] wherein the pH value of the composition is ≥6.0 to ≤9.0; and

[0176] The percentages by weight are in each case based on the total weight of the composition.

[0177] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0178] (A) at least one inorganic abrasive particle selected from the group consisting of metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamonds, organic hybrid particles, inorganic hybrid particles, and silicon dioxide;

[0179] (B) a corrosion inhibitor selected from at least methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts; and

[0180] (C) an aqueous medium; and

[0181] The pH value of the composition is ≥6.0 to ≤10.0.

[0182] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0183] (A) at least one inorganic abrasive particle selected from the group consisting of metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamonds, organic hybrid particles, inorganic hybrid particles, and silicon dioxide;

[0184] (B) a corrosion inhibitor selected from at least methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0185] (C) an aqueous medium; and

[0186] (D) at least one corrosion inhibitor selected from polyacrylamide or acrylamide copolymers; and

[0187] The pH value of the composition is ≥6.0 to ≤10.0.

[0188] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0189] (A) Colloidal silica;

[0190] (B) a corrosion inhibitor selected from at least methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0191] (C) an aqueous medium; and

[0192] (D) at least one corrosion inhibitor selected from polyacrylamide or acrylamide copolymers; and

[0193] The pH value of the composition is ≥6.0 to ≤10.0.

[0194] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0195] (A) Colloidal silica;

[0196] (B) a corrosion inhibitor selected from at least methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0197] (C) an aqueous medium; and

[0198] (D) at least one corrosion inhibitor selected from polyacrylamide or acrylamide copolymers;

[0199] (E) at least one oxidizing agent; and

[0200] The pH value of the composition is ≥6.0 to ≤9.0.

[0201] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0202] (A) ≥0.01 wt % to ≤10.0 wt % of at least one inorganic abrasive particle selected from metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamond, organic hybrid particles, inorganic hybrid particles, and silicon dioxide;

[0203] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0204] (C) an aqueous medium; and

[0205] (D) ≥ 0.001 wt % to ≤ 0.5 wt % of at least one corrosion inhibitor selected from polyacrylamide or acrylamide copolymers;

[0206] wherein the pH value of the composition is ≥5.5 to ≤10.0; and

[0207] The percentages by weight are in each case based on the total weight of the composition.

[0208] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0209] (A) ≥0.01 wt % to ≤10.0 wt % of at least one inorganic abrasive particle selected from metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamond, organic hybrid particles, inorganic hybrid particles, and silicon dioxide;

[0210] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0211] (C) an aqueous medium; and

[0212] (D) ≥ 0.001 wt % to ≤ 0.5 wt % of at least one corrosion inhibitor selected from polyacrylamide or acrylamide copolymers;

[0213] wherein the pH value of the composition is ≥6.0 to ≤10.0; and

[0214] The percentages by weight are in each case based on the total weight of the composition.

[0215] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0216] (A) ≥0.01 wt % to ≤10.0 wt % of at least one inorganic abrasive particle selected from metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamond, organic hybrid particles, inorganic hybrid particles, and silicon dioxide;

[0217] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0218] (C) aqueous medium;

[0219] (D) ≥ 0.001 wt% to ≤ 0.5 wt% of at least one corrosion inhibitor selected from polyacrylamide or acrylamide copolymers; and

[0220] (E) ≥ 0.01 wt % to ≤ 1.0 wt % of at least one oxidizing agent;

[0221] wherein the pH value of the composition is ≥6.0 to ≤9.0; and

[0222] The percentages by weight are in each case based on the total weight of the composition.

[0223] Another preferred embodiment of the present invention relates to a composition comprising the following components:

[0224] (A) ≥0.01 wt % to ≤5 wt % of at least one inorganic abrasive particle selected from metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamond, organic hybrid particles, inorganic hybrid particles, and silicon dioxide;

[0225] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0226] (C) aqueous medium;

[0227] (D) ≥ 0.001 wt% to ≤ 0.3 wt% of at least one corrosion inhibitor selected from polyacrylamide or acrylamide copolymers; and

[0228] (E) ≥ 0.01 wt % to ≤ 1.0 wt % of at least one oxidizing agent;

[0229] wherein the pH value of the composition is ≥6.0 to ≤9.0; and

[0230] The percentages by weight are in each case based on the total weight of the composition.

[0231] Methods for preparing compositions for inhibiting tungsten etching are generally known. These methods can be used to prepare the compositions of the present invention. This can be done by dispersing or dissolving the above-mentioned components (A), (B), (D) and (E) in an aqueous medium (C), preferably water, and optionally adjusting the pH by adding an acid, base, buffer or pH adjuster (F). For this purpose, conventional and standard mixing methods and mixing devices can be used, such as stirred vessels, high shear impellers, ultrasonic mixers, homogenizer nozzles or countercurrent mixers.

[0232] One aspect of the present invention relates to a method for manufacturing a semiconductor device, comprising chemically mechanically polishing (CMP) a substrate (S) for use in the semiconductor industry in the presence of the above-mentioned composition, wherein the substrate (S) comprises:

[0233] (i) tungsten, and / or

[0234] (ii) Tungsten alloy.

[0235] There are no particular restrictions on the semiconductor devices that can be manufactured by the method of the present invention. Semiconductor devices can be electronic components comprising semiconductor materials, such as silicon, germanium, and III-V materials. Semiconductor devices can be those manufactured as single discrete devices, or those manufactured as integrated circuits (ICs), which are composed of several devices manufactured and interconnected on a wafer. Semiconductor devices can be two-terminal devices such as diodes, three-terminal devices such as bipolar transistors, four-terminal devices such as Hall effect sensors, or multi-terminal devices. Preferably, the semiconductor device is a multi-terminal device. The multi-terminal device can be a logic device, such as an integrated circuit and a microprocessor, or a memory device, such as a random access memory (RAM), a read-only memory (ROM), and a phase change random access memory (PCRAM). Preferably, the semiconductor device is a multi-terminal logic device. In particular, the semiconductor device is an integrated circuit or a microprocessor.

[0236] Typically, tungsten (W) is used for copper interconnects in integrated circuits. Excess tungsten on dielectrics can be removed by known chemical mechanical polishing methods.

[0237] Generally, the tungsten / tungsten alloy can be prepared or obtained in different ways, such as ALD, PVD or CVD methods. Generally, the tungsten and / or tungsten alloy can have any type, form or shape. The tungsten and / or tungsten alloy preferably has a layer and / or overgrowth shape. If the tungsten and / or tungsten alloy has a layer and / or overgrowth shape, the tungsten and / or tungsten alloy content is preferably greater than 90% by weight of the corresponding layer and / or overgrowth, more preferably greater than 95% by weight, most preferably greater than 98% by weight, particularly greater than 99% by weight, for example greater than 99.9% by weight. The tungsten and / or tungsten alloy preferably fills or grows in a trench or plug between other substrates, more preferably fills or grows in a dielectric material such as SiO2, silicon, low-k (BD1, BD2) or ultra-low-k material, or in a trench or plug in other insulating and semiconductor materials for use in the semiconductor industry. For example, in a through silicon via (TSV) intermediate process, after the TSV is exposed from the back side of the wafer, insulating materials such as polymers, photoresists and / or polyimides can be used as insulating materials between subsequent process steps of wet etching and CMP for insulation / isolation properties.

[0238] In an embodiment of the present invention, the static etch rate (SER) of tungsten is less than In a preferred embodiment of the present invention, the static etch rate (SER) of tungsten is less than In a more preferred embodiment of the present invention, the static etch rate (SER) of tungsten is less than / minute.

[0239] One aspect of the present invention relates to the use of the compositions of the present invention for inhibiting tungsten etching.

[0240] The composition of the present invention has at least one of the following advantages:

[0241] (1) The compositions and methods of the present invention exhibit improved performance in inhibiting etching, particularly tungsten etching,

[0242] (2) The compositions and methods of the present invention prevent tungsten corrosion during chemical mechanical polishing of tungsten-containing substrates,

[0243] (3) The compositions of the present invention provide stable formulations or dispersions in which phase separation does not occur,

[0244] (4) The method of the present invention is easy to apply and requires as few steps as possible,

[0245] (5) The compositions and methods of the present invention do not affect the polishing rate of the substrate during chemical mechanical polishing.

[0246] Implementation Plan

[0247] A list of embodiments is provided below to further illustrate the present disclosure and is not intended to limit the present disclosure to the specific embodiments listed below.

[0248] 1. A composition for inhibiting tungsten etching, comprising:

[0249] (A) at least one inorganic abrasive particle;

[0250] (B) at least one corrosion inhibitor selected from the group consisting of methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts; and

[0251] (C) an aqueous medium; and

[0252] The pH value of the composition is ≥5.0 to ≤11.0.

[0253] 2. The composition according to embodiment 1, wherein the at least one inorganic abrasive particle (A) is selected from metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamond, organic hybrid particles, inorganic hybrid particles and silica.

[0254] 3. The composition according to embodiment 1, wherein the at least one inorganic abrasive particle (A) has an average particle size of ≧1 nm to ≦1000 nm as determined by dynamic light scattering techniques.

[0255] 4. The composition according to embodiment 1, wherein the at least one inorganic abrasive particle (A) is present in a concentration of ≥0.01 wt. % to ≤10.0 wt. %, based on the total weight of the composition.

[0256] 5. The composition according to any one of embodiments 1 to 4, wherein the at least one corrosion inhibitor (B) is benzethonium.

[0257] 6. The composition of any one of embodiments 1 to 5, wherein the benzethonium salt is selected from benzethonium fluoride, benzethonium chloride, benzethonium bromide, benzethonium hydroxide, and benzethonium citrate.

[0258] 7. The composition of any one of embodiments 1 to 6, wherein the methylbenzethonium salt is selected from methylbenzethonium fluoride, methylbenzethonium chloride, methylbenzethonium bromide, methylbenzethonium hydroxide, and methylbenzethonium citrate.

[0259] 8. The composition according to any one of embodiments 1 to 7, wherein the at least one corrosion inhibitor (B) is present in a concentration of ≧0.0001 wt. % to ≦0.009 wt. %, based on the total weight of the composition.

[0260] 9. The composition according to any one of embodiments 1 to 8, wherein the aqueous medium (C) is deionized water.

[0261] 10. The composition of any one of embodiments 1-9, wherein the pH of the composition is ≥5.0 to ≤10.0.

[0262] 11. The composition of any one of embodiments 1-10, wherein the pH of the composition is ≥6.0 to ≤9.0.

[0263] 12. The composition according to any one of embodiments 1 to 11, further comprising at least one corrosion inhibitor (D) selected from polyacrylamide and polyacrylamide copolymers.

[0264] 13. The composition of embodiment 12, wherein the polyacrylamide copolymer is an anionic or nonionic polyacrylamide copolymer.

[0265] 14. The composition of embodiment 12, wherein the polyacrylamide is a homopolymer of polyacrylamide.

[0266] 15. The composition according to embodiment 12, wherein the at least one corrosion inhibitor (D) is present in a concentration of ≥0.001 wt. % to ≤0.5 wt. %, based on the total weight of the composition.

[0267] 16. The composition according to embodiment 12, wherein the at least one corrosion inhibitor (D) has a weight average molecular weight of ≧5000 g / mol to ≦50,000 g / mol, as determined by gel permeation chromatography.

[0268] 17. The composition of any one of embodiments 1-16, further comprising at least one oxidizing agent (E) selected from the group consisting of organic peroxides, inorganic peroxides, persulfates, iodates, potassium hydroxide, ferric nitrate, periodic acid, periodates, permanganates, perchloric acid, perchlorates, phosphoric acid, bromic acid, and bromates.

[0269] 18. The composition according to embodiment 17, wherein the at least one oxidizing agent (E) is present in a concentration of ≥0.01 wt. % to ≤1.0 wt. %, based on the total weight of the composition.

[0270] 19. The composition of any one of embodiments 1-18, comprising:

[0271] (A) ≥0.01 wt % to ≤10.0 wt % of at least one inorganic abrasive particle;

[0272] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts; and

[0273] (C) aqueous medium;

[0274] wherein the pH value of the composition is ≥5.0 to ≤10.0; and

[0275] The percentages by weight are in each case based on the total weight of the composition.

[0276] 20. The composition of any one of embodiments 1-18, comprising:

[0277] (A) ≥0.01 wt % and ≤10.0 wt % of at least one inorganic abrasive particle;

[0278] (B) ≥0.0001 wt % to ≤0.009 wt % of at least one corrosion inhibitor selected from methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0279] (C) an aqueous medium; and

[0280] (D) ≥ 0.001 wt % to ≤ 0.5 wt % of at least one corrosion inhibitor selected from polyacrylamide and polyacrylamide copolymers;

[0281] wherein the pH value of the composition is ≥5.5 to ≤10.0; and

[0282] The percentages by weight are in each case based on the total weight of the composition.

[0283] 21. The composition of any one of embodiments 1-18, comprising:

[0284] (A) at least one inorganic abrasive particle selected from the group consisting of metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamonds, organic hybrid particles, inorganic hybrid particles, and silicon dioxide;

[0285] (B) a corrosion inhibitor selected from at least methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts; and

[0286] (C) an aqueous medium; and

[0287] The pH value of the composition is ≥5.5 to ≤10.0.

[0288] 22. The composition of any one of embodiments 1-18, comprising:

[0289] (A) at least one inorganic abrasive particle selected from the group consisting of metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamonds, organic hybrid particles, inorganic hybrid particles, and silicon dioxide;

[0290] (B) a corrosion inhibitor selected from at least methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0291] (C) an aqueous medium; and

[0292] (D) at least one corrosion inhibitor (D) selected from polyacrylamide or acrylamide copolymers; and

[0293] The pH value of the composition is ≥5.5 to ≤10.0.

[0294] 23. The composition of any one of embodiments 1-18, comprising:

[0295] (A) ≥0.01 wt % to ≤10.0 wt % of at least one inorganic abrasive particle selected from metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamond, organic hybrid particles, inorganic hybrid particles, and silicon dioxide;

[0296] (B) ≥0.0001 wt % to ≤0.009 wt % of a corrosion inhibitor selected from at least methylbenzethonium, methylbenzethonium salts, benzethonium, and benzethonium salts;

[0297] (C) an aqueous medium; and

[0298] (D) ≥0.001 wt% to ≤0.5 wt% of at least one selected from polyacrylamide or acrylamide co-

[0299] Corrosion inhibitors for polymers (D);

[0300] wherein the pH value of the composition is ≥5.5 to ≤10.0; and

[0301] The percentages by weight are in each case based on the total weight of the composition.

[0302] 24. A method for manufacturing a semiconductor device, comprising chemically mechanically polishing a substrate (S) for use in the semiconductor industry in the presence of a composition as defined in any one of embodiments 1 to 23, wherein the substrate (S) comprises:

[0303] (i) tungsten, and / or

[0304] (ii) Tungsten alloy.

[0305] 25. The method of embodiment 24, wherein the static etch rate (SER) of tungsten is less than / minute.

[0306] 26. Use of the composition according to any one of embodiments 1 to 23 for inhibiting tungsten etching.

[0307] While the invention has been described with reference to specific embodiments thereof, certain modifications and equivalents will be apparent to those skilled in the art and are intended to be included within the scope of this invention. Example

[0308] The present invention is illustrated in detail by the following working examples. More particularly, the test methods described below are part of the general disclosure of the present application and are not limited to the specific working examples described.

[0309] The general procedure for preparing the slurries and the experimental description are as follows.

[0310] Components:

[0311] ●Silica particles, which can be found under the trade name PL-3 was commercially available from Fuso Chemical Corporation;

[0312] Benzethonium chloride, available from Sigma Aldrich;

[0313] Deionized water, available from BASF SE;

[0314] Polyacrylamide, available from Sigma Aldrich;

[0315] • Hydrogen peroxide, available from BASF SE.

[0316] Slurry composition:

[0317] The slurry composition comprises:

[0318] (A) Inorganic abrasive: silica particles;

[0319] (B) Corrosion inhibitor: benzethonium chloride;

[0320] (C) Deionized water (DIW);

[0321] (D) Corrosion inhibitor: polyacrylamide;

[0322] (E) Oxidant: hydrogen peroxide (H2O2).

[0323] Immediately before the slurry was used for static etch rate (SER) measurement (1-15 minutes), an oxidizing agent (E) (1% H2O2) was added.

[0324] method

[0325] Procedure for preparing slurry composition

[0326] The components of the slurry composition were thoroughly mixed, and all mixing procedures were performed under stirring. Stock aqueous solutions of each compound (A), (B), (D) and (E) were prepared by dissolving the required amount of each compound in ultrapure water (UPW). For the stock solutions of each component, potassium hydroxide (KOH) or phosphoric acid (H3PO4) was preferably used to assist dissolution. The pH of the stock solution was adjusted to ~10 with KOH or to ~6 with H3PO4. The corresponding additive concentration for the (B) stock solution was 0.001 wt% benzethonium chloride solution, and the concentration of (D) and (E) was 1.0 wt%. For (A), the dispersion provided by the supplier was used, typically at an abrasive concentration of about 20-30 wt%. The oxidizing agent (E) was used as a 30 wt% stock solution.

[0327] To prepare 10,000 g of slurry, add the required amount of (B) stock solution to a mixing tank or beaker and then adjust the pH to 6 or 10 by adding KOH at a stirring rate of 350 rpm. Add the amount of (D) stock solution to achieve the desired concentration. Maintain the solution at the desired pH of 6 or 10 with KOH. Then add the required amount of (A). To adjust the final concentration, add (C) as the balance water relative to the desired amount of oxidant stock solution. Adjust the pH to the desired value with KOH (or H3PO4). Add the oxidant in the required amount (0.1 wt%) approximately 60 minutes before etching.

[0328] Inorganic particles (A) used in the examples

[0329] Colloidal cocoon-like silica particles (A1) (e.g., PL-3).

[0330] Procedure for particle shape characterization

[0331] A cocoon-shaped aqueous dispersion of silica particles with a solid content of 20% by weight was dispersed on carbon foil and dried. The dried dispersion was analyzed using energy-filtered transmission electron microscopy (EF-TEM) (120 kV) and scanning electron microscopy secondary electron imaging (SEM-SE) (5 kV). EF-TEM images with a 2k, 16-bit, 0.6851 nm / pixel resolution were used for analysis. The images were binary encoded using a threshold after noise suppression. Subsequently, the particles were manually separated. Cover and edge particles were distinguished and not used for analysis. The ECD, shape factor, and sphericity, as defined above, were calculated and statistically classified.

[0332] A2 is an agglomerated particle with a specific surface area of ​​about 90 m2 / g, an average primary particle size (d1) of 35 nm and an average secondary particle size (d2) of 75 nm (determined by a Horiba instrument using dynamic light scattering technique) (e.g. PL-3H).

[0333] pH measurement

[0334] The pH value was measured using a pH combination electrode (Schott, blue line 22 pH electrode).

[0335] Static Etch Rate (SER) Experiment

[0336] The SER experiment was performed as follows:

[0337] • 2.5 x 2.5 cm PVD tungsten (W) was cut and washed with deionized water (DIW).

[0338] • Each sample was treated with 0.1% citric acid solution for 4 minutes and then washed with DIW.

[0339] ●Measure the tungsten (W) film thickness (d 前 ).

[0340] • 300 ml of the freshly prepared slurry with the desired hydrogen peroxide concentration was placed in a beaker and brought to 60°C.

[0341] • In the SER apparatus, a tungsten (W) sample was placed in the slurry and kept in the slurry for 10 minutes.

[0342] ●Take out the tungsten (W) sample, rinse it with DIW for 1 minute, and dry it with nitrogen.

[0343] ● Use the same equipment to measure the tungsten (W) film thickness (d 后 ).

[0344] The static etch rate (SER) is determined by the following formula:

[0345]

[0346] Table 1:

[0347]

[0348] *Not within the scope of this invention

[0349] Results and Discussion

[0350] Table 1 shows the static etch rate (SER) of different slurry compositions. Compared to the slurry without any benzethonium chloride as corrosion inhibitor (B), the addition of benzethonium chloride as corrosion inhibitor (B) in the slurry provides a SER of less than / min of tungsten SER (Examples 1, 2, 3 and 4).

[0351] Table 1 shows the effect of benzethonium chloride concentration in the slurry on the SER. Concentrations of benzethonium chloride at or above 0.01 wt% resulted in unstable formulations. Table 1 also shows the significant effect of pH on the SER of tungsten. pH values ​​of 5-11 resulted in lower static tungsten (W) etching rates. Specifically, as shown in Table 1, lower static tungsten etching rates were observed in the pH range of 6 and higher.

[0352] The compositions of the examples of the present invention exhibit improved properties of low etching behavior of tungsten and high dispersion stability.

Claims

1. A composition for inhibiting tungsten etching, comprising: (A) at least one inorganic abrasive particle; (B) at least one corrosion inhibitor selected from benzethonium salts; and (C) an aqueous medium; and wherein the pH value of the composition is ≥6.0 to ≤8.0, wherein the at least one corrosion inhibitor (B) is present in a concentration of ≧0.0001 wt % to ≦0.009 wt %, based on the total weight of the composition.

2. The composition according to claim 1, wherein the at least one inorganic abrasive particle (A) is selected from the group consisting of metal oxides, metal nitrides, metal carbides, silicides, borides, ceramics, diamond, organic hybrid particles, inorganic hybrid particles and silica. 3 . The composition according to claim 1 , wherein the at least one inorganic abrasive particle (A) has an average particle size of ≧1 nm to ≦1000 nm as determined by dynamic light scattering techniques.

4. The composition of claim 1, wherein the benzethonium salt is selected from the group consisting of benzethonium fluoride, benzethonium chloride, benzethonium bromide, benzethonium hydroxide and benzethonium citrate.

5. The composition of claim 2, wherein the benzethonium salt is selected from the group consisting of benzethonium fluoride, benzethonium chloride, benzethonium bromide, benzethonium hydroxide and benzethonium citrate.

6. The composition of claim 3, wherein the benzethonium salt is selected from the group consisting of benzethonium fluoride, benzethonium chloride, benzethonium bromide, benzethonium hydroxide and benzethonium citrate.

7. The composition according to claim 1, wherein the aqueous medium (C) is deionized water.

8. The composition according to claim 2, wherein the aqueous medium (C) is deionized water.

9. The composition according to claim 3, wherein the aqueous medium (C) is deionized water.

10. The composition according to claim 4, wherein the aqueous medium (C) is deionized water.

11. The composition according to claim 5, wherein the aqueous medium (C) is deionized water.

12. The composition according to claim 6, wherein the aqueous medium (C) is deionized water.

13. The composition according to any one of claims 1 to 12, further comprising at least one corrosion inhibitor (D) selected from polyacrylamide and polyacrylamide copolymers.

14. The composition according to claim 13, wherein the at least one corrosion inhibitor (D) is present in a concentration of ≥0.001 wt.-% to ≤0.5 wt.-%, based on the total weight of the composition.

15. The composition according to any one of claims 1 to 12, further comprising at least one oxidizing agent (E) selected from the group consisting of organic peroxides, inorganic peroxides, persulfates, iodates, potassium hydroxide, ferric nitrate, periodic acid, periodates, permanganates, perchloric acid, perchlorates, phosphoric acid, bromic acid and bromates.

16. The composition according to claim 13, further comprising at least one oxidizing agent (E) selected from the group consisting of organic peroxides, inorganic peroxides, persulfates, iodates, potassium hydroxide, ferric nitrate, periodic acid, periodates, permanganates, perchloric acid, perchlorates, phosphoric acid, bromic acid, and bromates.

17. The composition according to claim 14, further comprising at least one oxidizing agent (E) selected from the group consisting of organic peroxides, inorganic peroxides, persulfates, iodates, potassium hydroxide, ferric nitrate, periodic acid, periodates, permanganates, perchloric acid, perchlorates, phosphoric acid, bromic acid, and bromates.

18. The composition according to claim 15, wherein the at least one oxidizing agent (E) is present in a concentration of ≥ 0.01 wt% to ≤ 1.0 wt%, based on the total weight of the composition.

19. The composition according to claim 16 or 17, wherein the at least one oxidizing agent (E) is present in a concentration of ≥ 0.01 wt.-% to ≤ 1.0 wt.-%, based on the total weight of the composition.

20. A method for manufacturing a semiconductor device, comprising chemically mechanically polishing a substrate (S) for use in the semiconductor industry in the presence of a composition as defined in any one of claims 1 to 19, wherein the substrate (S) comprises: (i) tungsten, and / or (ii) Tungsten alloy.

21. The method of claim 20, wherein the static etch rate (SER) of tungsten is less than 30 Å / min.

22. Use of the composition according to any one of claims 1 to 19 for inhibiting tungsten etching.

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