Transition metal polishing

Abstract

The present invention provides compositions useful for polishing transition metal-containing surfaces typically found on microelectronic devices. In one aspect, the present invention provides compositions comprising a liquid carrier; titania abrasive particles, the particles being at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles, the coated titania abrasive particles having an average diameter of about 50 nm to about 250 nm; and a corrosion inhibitor. The present compositions are advantageously utilized to polish microelectronic device substrates having a transition metal-containing surface thereon. In certain embodiments, the surface is selected from molybdenum and ruthenium-containing films and exhibits significantly improved selectivity compared to thermal oxides.

Description

[Technical Field]

[0001] The present invention relates generally to the field of microelectronic device manufacturing, and more particularly to compositions and methods for chemical-mechanical polishing of transition metals such as molybdenum, tungsten, cobalt, copper, and ruthenium surfaces. [Background technology]

[0002] Microelectronic device wafers are used to form integrated circuits. They contain a substrate, such as silicon, on which areas are patterned for the deposition of different materials with insulating, conductive, or semiconducting properties. To achieve the correct patterning, excess material used in forming layers on the substrate must be removed. Furthermore, to create functional and reliable circuits, it is often important to ensure that the surface of the microelectronic wafer is flat or planar prior to subsequent processing. Therefore, certain surfaces of the microelectronic device wafer must be planarized and / or polished. Furthermore, in the case of optical devices, the surface may need to be smoothed for light transmission or subsurface damage removed.

[0003] Chemical-mechanical polishing or planarization ("CMP") is a process by which material is removed from the surface of a microelectronic device wafer, resulting in planarization and polishing, by combining physical processes, such as grinding, with chemical processes, such as oxidation and chelation. In its most rudimentary form, CMP involves applying a slurry, e.g., a solution of abrasives and active chemicals, to a polishing pad that buffs the surface of the microelectronic device wafer to achieve the removal, planarization, and polishing process. Typically, the removal or polishing process is not desirable to consist of purely physical or purely chemical action; rather, a synergistic combination of both is required to achieve rapid and uniform removal. In integrated circuit manufacturing, CMP slurries must be able to preferentially remove films, including complex layers of metals and other materials, to produce highly planar surfaces for subsequent photolithography, patterning, etching, and thin-film processing. In a conventional CMP operation, a substrate carrier or polishing head is attached to a carrier assembly and positioned in contact with the polishing pad of a CMP apparatus. The carrier assembly applies a controllable pressure to the substrate, pressing it against the polishing pad. The pad is then moved relative to the substrate.

[0004] Molybdenum metal is used in microelectronic device interconnects, photomasks, and the like. Molybdenum is typically present in excess on devices, necessitating removal of the excess by polishing or lapping. Molybdenum polishing typically results in low removal rates when using silica abrasive compositions. High corrosion rates are often encountered when oxidizing agents, such as hydrogen peroxide, are used.

[0005] Ruthenium is being considered as a barrier material for copper interconnects, as a bottom electrode material for metal-insulator-metal capacitors, and as a potential replacement for Ta / TaN as a next-generation liner and conductive metal. Ruthenium can be polished using abrasives in conjunction with oxidizers. Unfortunately, some of these compositions raise safety and toxicity concerns due to reaction products generated during such polishing processes. Furthermore, ruthenium polishing often involves low removal rates and high etch rates when using traditional (colloidal) silica and iodate (i.e., oxidizer) chemistries. Furthermore, such methodologies often result in severe pad contamination along with poor reproducibility, especially under neutral to alkaline pH conditions. In this regard, pad contamination is believed to be due to byproducts formed as a result of ruthenium oxidation, which can ultimately generate insoluble species that can cause undesirable scratches on the ruthenium surface.

[0006] Therefore, there is a need for new and improved compositions and methods for polishing molybdenum and ruthenium that do not suffer from these difficulties. Summary of the Invention

[0007] In summary, the present invention provides compositions useful for polishing transition metal-containing surfaces typically found on microelectronic devices. In one aspect, the present invention provides a composition comprising: Liquid carrier; the particles are at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles; titania abrasive particles, wherein the coated titania abrasive particles have an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors A composition comprising:

[0008] In the method of the present invention, the composition is advantageously utilized to polish microelectronic device substrates having a transition metal-containing surface thereon. In certain embodiments, the surface is selected from molybdenum and ruthenium-containing films. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a graph showing the etch rate of a molybdenum substrate in Angstroms per minute versus the concentration of a corrosion inhibitor as represented by the hatched columns. The designation "SER" refers to the static etch rate (dotted columns). The data corresponds to Example 4. [Figure 2] 1 shows the surface finish of molybdenum surfaces polished using the composition of the present invention. The data corresponds to Example 5. [Figure 3] 1 is a graph of removal rates in Angstroms per minute for various abrasives and abrasive / oxidizer combinations. DETAILED DESCRIPTION OF THE INVENTION

[0010] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally used in its sense including "and / or" unless the content clearly dictates otherwise.

[0011] The term "about" generally refers to a range of numbers that are considered equivalent to the recited value (e.g., having the same function or result). In many cases, the term "about" may include numbers that are rounded to the nearest significant figure.

[0012] Numerical ranges expressed using endpoints include all numbers subsumed within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0013] The compositions of the present invention are useful as CMP polishing compositions (i.e., slurries) for transition metal-containing materials. In one embodiment, the metals include ruthenium, rhodium, palladium, osmium, iridium, platinum, gold, silver, copper, and rhenium. In another embodiment, the metals include tungsten, cobalt, copper, and both oxides and nitrides of these metals. In another embodiment, the metals include ruthenium and molybdenum. Thus, the present invention provides, in a first aspect, a method for producing a CMP polishing composition comprising: Liquid carrier; the particles are at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles; titania abrasive particles, wherein the coated titania abrasive particles have an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors A composition comprising:

[0014] In the present invention, coated titania (TiO) particles are widely available commercially. Such coated titania particles generally have an average diameter of about 50 to about 250 nm, about 100 to about 250 nm, about 50 to about 150 nm, or about 20 to about 50 nm. Coating these titania particles with amorphous silica or alumina can be achieved by known methodologies. See, for example, "Dense silica coating of titania nanoparticles by seeded polymerization technique," Ahmed Mohamed El-Toni, Shu Yin, and Tsugio Sato, Colloids and Surfaces A: Physicochemical and Engineering Aspects, Vol. 274, Nos. 1-3, February 15, 2006, pp. 229-233. Coating of titania with alumina (Al2O3) can be achieved by deposition in the gas phase by hydrolysis or decomposition of volatile substances; addition of oxides, hydroxides, or substances that can be absorbed onto the surface during pigment milling, resulting in a partial coating of the pigment surface; or precipitation of the coating onto suspended TiO2 particles from an aqueous solution.

[0015] In one embodiment, the titania abrasive particles are in the rutile form. Generally, component b above, i.e., the coated titania particles, is primarily composed of titanium dioxide (with an alumina or amorphous silica coating), although dopants or materials other than titanium dioxide may be present in small amounts within the titania abrasive particles, such as up to about 5% by weight, up to about 2% by weight, or up to about 1%.

[0016] As noted above, the compositions of the present invention include at least one organic corrosion inhibitor. Essentially, these organic corrosion inhibitors fall into the general class of surfactants. As used herein, the term "surfactant" refers to an organic compound that reduces the surface tension (or interfacial tension) between two liquids or between a liquid and a solid, and is typically an organic amphiphilic compound containing a hydrophobic group (e.g., a hydrocarbon (e.g., alkyl) "tail") and a hydrophilic group. In one embodiment, these surfactants or metal corrosion inhibitors are cationic surfactants. Cationic surfactants are essentially surface-active molecules with at least one positively charged moiety. In one embodiment, cationic surfactants are those having a C6-C8 18 Ammonium halides are selected from C6 to C 18 The " modifier refers to the number of carbon atoms in the surfactant, which may include aliphatic and aromatic moieties. In another embodiment, the cationic surfactant is 12 ~C 18 The ammonium halide is selected from the group consisting of ammonium halides.

[0017] Exemplary cationic surfactants (corrosion inhibitors) include cetyltrimethylammonium bromide (CTAB) (also known as hexadecyltrimethylammonium bromide), hexadecyltrimethylammonium chloride (CTAC), heptadecanefluorooctanesulfonic acid, tetraethylammonium halides, stearyltrimethylammonium chloride, 4-(4-diethylaminophenylazo)-1-(4-nitrobenzyl)pyridinium bromide, cetylpyridinium chloride monohydrate, benzalkonium chloride, benzalkonium bromide, benzethonium chloride, benzalkonium chloride, benzoyl benzoate ... Examples of suitable corrosion inhibitors / surfactants include, but are not limited to, diethyl dimethyl dodecyl ammonium, benzyl dimethyl hexadecyl ammonium chloride, hexadecyl trimethyl ammonium bromide, dimethyl dioctadecyl ammonium chloride, dodecyl trimethyl ammonium chloride, didodecyl dimethyl ammonium bromide, di(hydrogenated tallow) dimethyl ammonium chloride, tetraheptyl ammonium bromide, tetrakis(decyl) ammonium bromide, and oxyphenonium bromide, dimethyl dioctadecyl ammonium chloride, dimethyl dihexadecyl ammonium bromide, and di(hydrogenated tallow) dimethyl ammonium chloride. In one embodiment, the corrosion inhibitor / surfactant is selected from benzalkonium chloride and benzalkonium bromide.

[0018] These corrosion inhibitors / surfactants are typically present in amounts of about 0.0001 to about 5 weight percent, based on the total weight of the composition, and as found necessary by empirical observation.

[0019] In the compositions of the present invention, the relative amount of coated titania particles can be adjusted as desired for polishing a particular transition metal surface, based on the total weight of the composition. In some embodiments, the coated titania particles are present in an amount of about 0.001 to about 5 wt. %, or about 0.1 to about 1 wt. %, based on the total weight of the composition. Any suitable amount of abrasive can be present in the polishing composition, depending on both the surface to be polished and other conditions utilized. In some embodiments, the abrasive is present in the polishing composition at a concentration of about 0.0005 wt. % or greater, e.g., about 0.001 wt. % or greater, about 0.0025 wt. % or greater, about 0.005 wt. % or greater, about 0.01 wt. % or greater, about 0.025 wt. % or greater, or about 0.05 wt. % or greater. More typically, the abrasive is present in the polishing composition at a concentration of about 0.001 wt% or more, e.g., about 0.0025 wt% or more, about 0.005 wt% or more, about 0.01 wt% or more, about 0.025 wt% or more, or about 0.05 wt% or more. Alternatively, or in addition, the abrasive is present in the polishing composition at a concentration of about 30 wt% or less, e.g., about 20 wt% or less, about 10 wt% or less, about 5 wt% or less, about 1 wt% or less, about 0.5 wt% or less, about 0.1 wt% or less, or about 0.05 wt% or less. More typically, the abrasive is present in the polishing composition at a concentration of about 1 wt% or less, e.g., about 0.5 wt% or less, about 0.1 wt% or less, or about 0.05 wt% or less. Thus, the abrasive can be present in the polishing composition within the range enclosed by any two of the aforementioned endpoints.For example, the abrasive may be present in the polishing composition in an amount of about 0.0005% by weight to about 10% by weight, e.g., about 0.001% by weight to about 10% by weight, about 0.001% by weight to about 1% by weight, about 0.001% by weight to about 0.5% by weight, about 0.001% by weight to about 0.1% by weight, about 0.001% by weight to about 0.05% by weight, about 0.005% by weight to about 10% by weight, about 0.005% by weight to about 1% by weight, about 0.005% by weight to about 0.5% by weight, about 0.005% by weight to about 0.1% by weight, or about 0. The abrasive may be present at a concentration of about 0.005% to about 0.05% by weight, about 0.01% to about 10% by weight, about 0.01% to about 1% by weight, about 0.01% to about 0.5% by weight, about 0.01% to about 0.1% by weight, about 0.01% to about 0.05% by weight, about 0.05% to about 10% by weight, about 0.05% to about 1% by weight, about 0.05% to about 0.5% by weight, about 0.05% to about 0.1% by weight, or about 0.05% to about 0.05% by weight. In certain embodiments, the abrasive is present at a concentration of about 0.001% to about 1% by weight.

[0020] In another embodiment, the composition of the present invention further comprises at least one oxidizing agent. As used herein, the term "oxidizing agent" refers to any chemical, other than ambient air, that can oxidize ruthenium beyond the +4 oxidation state. An exemplary list of such oxidizing agents includes, but is not limited to, peroxides (e.g., HO), periodate, oxone, bromate, bromite, hypobromite, chlorate, chlorite, hypochlorite, perchlorate, iodate, hypoiodate, periodate, cerium(IV) salts, permanganate, silver(III) salts, peroxyacetic acid, organic halooxy compounds, monoperoxysulfates, monoperoxysulfites, monoperoxythiosulfates, monoperoxyphosphates, monoperoxypyrophosphates, and monoperoxyhypophosphates. Further oxidizing agents include hydrogen peroxide; percompounds such as salts and acids containing peroxomonosulfate, perborate, perchlorate, periodate, persulfate, permanganate, and peracetate anions; and amine-N-oxides. Further examples include FeCl3, FeF3, Fe(NO3)3, Sr(NO3)2, COF3, MnF3, ozone, 2KHSO5·KHSO4·K7SO4, iodic acid, vanadium(V) oxide, vanadium(IV, V) oxide, ammonium vanadate, ammonium polyatomic salts (e.g., ammonium peroxomonosulfate, ammonium chlorite (NH4ClO2), ammonium chlorate (NH4ClO3), ammonium iodate (NH4IO3), ammonium nitrate (NH4NO3), ammonium perborate (NH4BO3), ammonium perchlorate (NH4ClO4), ammonium periodate (NH4IO4), ammonium persulfate ((NH4)2S2O8), ammonium hypochlorite (NH4ClO)), ammonium tungstate ((NH4) 10H2(W2O7)), sodium polyatotnic salts (e.g., sodium persulfate (Na2S2O8), sodium hypochlorite (NaClO), sodium perborate), potassium polyatomic salts (e.g., potassium iodate (KIO3), potassium permanganate (KMnO4), potassium persulfate, nitric acid (HNO3), potassium persulfate (K2S2O8), potassium hypochlorite (KClO), tetramethylammonium polyatomic salts (e.g., tetramethylammonium chlorite ((N(CH3)4)ClO2), tetramethylammonium chlorate (N(CH3)4ClO3 ), tetramethylammonium iodate ((N(CH3)4)IO3), tetramethylammonium perborate ((N(CH3)4)BO3), tetramethylammonium perchlorate ((N(CH3)4)ClO4), tetramethylammonium periodate ((N(CH3)4)IO4), tetramethylammonium persulfate (N(CH3)4)SO8)), tetrabutylammonium polyatomic salts (e.g., tetrabutylammonium peroxomonosulfate), peroxotnonosulfuric acid, ferric nitrate (Fe(NO3)3), urea hydrogen peroxide ((CO(NH2)2)HO2), peracetic acid (CH3(CO)OOH), 1,4-benzoquinone, toluquinone, dimethyl-1,4-benzoquinone, chloranil, alloxan, N-methylmorpholine N-oxide, trimethylamine N-oxide, and combinations thereof. Other examples of oxidizing agents include perbromic acid, telluric trifluoroperacetic acid, m-chloroperbenzoic acid, t-butyl hydroperoxide, dibenzoyl peroxide, potassium peroxysulfate (e.g., Oxone® DuPont), methyl ethyl ketone peroxide, acetone peroxide, ethyl hydroperoxide, and cumene hydroperoxide.

[0021] In one embodiment, the amount of oxidizing agent ranges from about 0.001% to about 5% by weight, and in another embodiment, from about 0.001% to about 2% by weight, based on the total weight of the composition.

[0022] In certain embodiments, a peroxide oxidizing agent is used as the oxidizing agent in combination with a source of Fe(II) or Fe(III), such as Fe(NO3)3, in a Fenton reaction to generate hydroxyl radicals in situ.

[0023] The compositions of the present invention may also further comprise a pH stabilizer. Both organic and inorganic pH stabilizers can be used. Examples of inorganic pH stabilizers include phosphates, phthalates, bicarbonates, and silicates. Examples of organic pH stabilizers include amines, glycine, and N-cyclohexyl-2-aminoethanesulfonic acid. In certain embodiments, the compositions of the present invention will have a pH of about 2 to about 5. If necessary for a given composition, pH adjusters such as acetic acid, nitric acid, sulfuric acid, hydrochloric acid, and phosphoric acid may be utilized. To make a given composition more alkaline, pH adjusters such as KOH, tetramethylammonium hydroxide (TMAH), and tetrabutylammonium hydroxide (TBAH) may be utilized.

[0024] The composition may also further comprise a biocide such as a disinfectant. Examples of the disinfectant include tetramethylammonium chloride, tetraethylammonium chloride, tetrapropylammonium chloride, alkylbenzyldimethylammonium chloride, and alkylbenzyldimethylammonium hydroxide, 3,5-di-methyltetrahydro-1,3,5,2H-thiadiazine-2-thione, 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one, sodium chlorite, and sodium hypochlorite.

[0025] As described above, the composition includes a liquid carrier. The liquid carrier is composed of water (e.g., deionized water) and, optionally, further includes one or more water-miscible organic solvents. Examples of usable organic solvents include alcohols such as isopropyl alcohol, ethanol, 1-propanol, methanol, and 1-hexanol; aldehydes such as acetylaldehyde; ketones such as acetone, diacetone alcohol, and methyl ethyl ketone; esters such as ethyl formate, propyl formate, ethyl acetate, methyl acetate, methyl lactate, butyl lactate, and ethyl lactate; ethers including sulfoxides such as dimethyl sulfoxide (DMSO), tetrahydrofuran, dioxane, and diglyme; amides such as N,N-dimethylformamide, dimethylimidazolidinone, and N-methylpyrrolidone; polyhydric alcohols and derivatives thereof such as ethylene glycol, glycerol, diethylene glycol, and diethylene glycol monomethyl ether; and nitrogen-containing organic compounds such as acetonitrile, amylamine, isopropylamine, imidazole, and dimethylamine. In one embodiment, the liquid carrier is water alone, i.e., in the absence of an organic solvent.

[0026] In certain embodiments, the composition of the present invention consists of or consists essentially of components a. and b. above, with optional components described herein. In certain embodiments, the composition is substantially free of oxidizing agents. As used herein, the phrase "substantially free of oxidizing agents" refers to a composition containing less than about 1 ppm of oxidizing agent, for example, less than about 100 ppb, less than about 10 ppb, less than about 1 ppb, less than about 100 ppt, less than about 10 ppt, or less than about 1 ppt. In certain embodiments, the polishing composition is free of oxidizing agents (i.e., below detectable levels).

[0027] The polishing process can be carried out at temperatures between about 15°C and about 100°C. Higher temperatures are expected to increase the polishing rate of molybdenum or ruthenium. In one embodiment, the temperature range is between about 25°C and about 65°C. One way to reach higher temperatures is to preheat the slurry before feeding it into the CMP tool.

[0028] Regarding the polishing pad, generally, any type of polymer-based polishing pad can be used. Examples of polishing pads include polyurethane pads and suede pads. The pad thickness can vary from 0.1 mm to 25 mm. The hardness of the suede pad can vary from Asker C 5 to Asker 95. The compressibility of the suede pad can be from 0.1% to 40%. The pore size of the suede poromeric pad can vary from 2 microns to 100 microns, and in one embodiment, ranges from 20 to 60 microns. The poromeric pad layer can have a backing pad layer of poly(ethylene terephthalate) (PET) between 30 microns and 25 millimeters thick, or a foam or nonwoven material.

[0029] In addition to poromeric pads, polyurethane pads can also be used. Examples of polyurethane-based pads include Cabot Microelectronics' D-100 pad and Dow Electronics Materials' IC and Suba series. The hardness of such pads ranges from 5 to 99 Shore D. The porosity of such pads can vary from 0.1% to 40%. It should be noted that, in general, any other type of polymer material can be used with the slurry. In addition to using poromeric pads, metal pads (cast iron, copper, tin, etc.), granite, or resin surfaces can also be used as pads.

[0030] Equipment suitable for chemical mechanical polishing is commercially available. The method of the present invention generally includes mixing a slurry composition containing the above-mentioned components, placing the dielectric substrate to be polished in a CMP apparatus having a rotating pad, and then performing chemical mechanical polishing using the slurry composition of the present invention. In this polishing method, at least a portion of the surface of the dielectric substrate is removed or ground away, thereby obtaining a properly polished dielectric substrate.

[0031] Thus, in another aspect, the present invention provides a method for chemical-mechanical polishing a substrate comprising a surface comprising at least one transition metal, the method comprising: The base material Liquid carrier; the particles are at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles; titania abrasive particles, wherein the coated titania abrasive particles have an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors contacting the composition with a composition comprising: transferring the composition relative to the substrate; and grinding the substrate to remove a portion of the surface comprising at least one transition metal; The present invention provides a method comprising:

[0032] Advantageously, the compositions and methods of the present invention exhibit significantly improved removal rates, in some embodiments, greater than about 200%, when compared to conventional slurries. Additionally, the compositions and methods of the present invention exhibit selectivities for molybdenum over thermal oxide of about 100:1 for polishing molybdenum-containing films and about 12:1 for polishing ruthenium-containing films in certain embodiments.

[0033] The compositions of the present invention are easily formulated by simply adding the individual components and mixing to a uniform state. The compositions can be easily formulated as single-portion formulations or as multi-part formulations that are mixed at the time of use or before use. It will be understood that the concentration of each component can vary widely, i.e., at specific multiples of the composition, i.e., more dilute or more concentrated, and that the compositions described herein can variously and alternatively comprise, consist of, or consist essentially of any combination of components consistent with the present disclosure.

[0034] Thus, in another aspect, the present invention provides a kit comprising components selected from a., b. and c., together with any of the components described above, in one or more containers to be combined at the time of use. [Example]

[0035] Abbreviation DL = detection limit CMP = Chemical Mechanical Planarization or Polishing DIW = deionized water SER = static etch rate CI = corrosion inhibitor (listed as quantity)

[0036] Part A - Molybdenum Polishing In this Part A, all concentrations are expressed in weight percent unless otherwise indicated. Water was added to make the composition 100% by weight. Additionally, CMP experiments were performed using the procedures and experimental conditions set forth below. The data presented in the following examples was generated by polishing 1.75 inch by 1.75 inch coupons cut from blanket molybdenum wafers. The thickness of the molybdenum film was measured using a profilometer to be 5000 Å. This thickness was confirmed after receipt using a four-point resistivity probe.

[0037] Various abrasives were investigated, including colloidal silica, which is considered a conventional abrasive for polishing molybdenum surfaces. Point-of-use (PoU) slurries were prepared by diluting slurries with high solids loadings. The appropriate weight of the original slurry was mixed with deionized water (DIW) to achieve the desired solids loading. For example, 10.6 g of silica slurry containing 47 wt% original solids loading was stirred in 89.4 g of DIW to achieve a final particle loading of 5 wt%. The operating pH was varied throughout the study, as described in the following examples. Aqueous solutions of nitric acid and potassium hydroxide were used as pH adjusters.

[0038] The CMP tool used to perform the polishing runs was an Automet 250 supplied by Buehler, with a 12-inch platen size. The rotation speeds were set at 150 RPM for the base and 30 RPM for the head. The peristaltic slurry dosing pump was set to deliver polishing slurry at 30 ml / min during the test. Cabot D100 pads with concentric grooves were used for all runs except when testing the effect of pad variation on removal rate. The polishing time was set to 60 seconds. Pad temperature, where noted, was measured during polishing using an IR thermometer.

[0039] The change in film thickness due to polishing was determined by measuring the film thickness before and after polishing using a four-point resistivity probe. The polishing non-uniformity observed from the various film thickness values ​​of the polished samples was attributed to the non-uniform pressure distribution from the Buehler polisher. To account for this non-uniformity, the removal rate was determined based on the weight of the film lost during polishing.

[0040] Example 1 (Samples A to F) Slurries A through F were used to polish Mo coupons at an operating pH of 1.5 and a downpressure of 4 psi. Two different abrasives were used: silica and titania. All abrasives were sourced from different suppliers. These were "abrasive-only" slurries, meaning no oxidizing chemicals were introduced into these formulations. A downpressure of 4 psi was used throughout. The solids loadings and corresponding removal rates for each slurry are listed in Table 1. As is evident from the table values, the titania-based slurries yielded the highest removal rates among all polishing runs in this group. The higher removal rate of slurry E, containing 410 nm APS titania particles, is likely due to its larger particle size. However, the comparable rates observed by polishing in the presence of slurries F and G, containing 200 nm APS titania particles, were surprising. This higher removal rate is attributed to the surface modification of the titania particles in these slurries. The novelty of this surface modification comes from an inorganic coating of transition metal oxides doped onto the surface. This surface functionalization imparts catalytic activity to the titania particles, allowing them to act as heterogeneous catalytic centers upon contact with a Mo surface. This behavior mimics the CMP effect observed when polishing a Mo surface with a slurry containing these particles. This effect is significant enough to maintain removal rates even at solids loadings as low as 1%. TIFF0007801373000001.tif122170

[0041] Example 2 Mo coupons were further polished using "abrasive only" slurries containing the unique coated titania particles described in Example 1, this time as a function of operating pH. The operating pH was varied between 1.5 and 13, with a 5% solids loading and a downpressure of 4 psi. Table 2 shows the Mo removal rates corresponding to each operating pH. The Mo removal rate clearly exhibits a strong dependence on operating pH, with the strongly acidic slurries yielding the highest removal rates. The effect of pH was more pronounced with titania abrasives as opposed to silica abrasives, which exhibited higher removal rates. The static etch rate (SER) of Mo at this pH was below the detection limit. TIFF0007801373000002.tif65170

[0042] Example 3 To investigate the performance of the slurry in the presence of various pads with different hardness values, Mo coupons were polished in the presence of slurry F, this time on various polishing pads at a constant operating pH of 1.5. The removal rates associated with the various pads, along with their respective hardness values, are shown in Table 2. The hardness values ​​were measured on the Shore D scale using a durometer purchased from Electromatic Equipment Co. Inc. Softer pads (those with lower hardness) exhibited higher removal rates, which is intuitively understandable because the softer the pad, the greater the contact area between the pad and the Mo surface. TIFF0007801373000003.tif71170

[0043] Example 4 Slurry G was further modified by adding an oxidizer to investigate the removal rate enhancement due to oxidation chemistry between Mo and the oxidizer. Hydrogen peroxide was added at a concentration of 0.1% as the oxidizer. A 100% increase was observed after the addition of the oxidizer. However, the SER was significantly higher than that of the "abrasive alone" formulation. Various corrosion inhibitors (CIs 1-8, dodecyltrimethylammonium bromide (1), glycine (2), benzotriazole (3), imidazoline oleate (4), secondary alkyl sulfonate (5), ammonium lauryl sulfate (6), benzalkonium chloride (7), and benzethonium chloride (8)) were added. Table 4 shows the room temperature SER data in the presence of these inhibitors at an oxidizer concentration of 0.1% and operating pH. Two inhibitors, CI-7 and CI-8, showed the greatest effect, with SER values ​​below the detection limit. TIFF0007801373000004.tif95170

[0044] Example 5 After confirming that the SER values ​​were significantly reduced in the presence of Slurries G7 and G8, the formulation of Slurry G was further modified to introduce a Fenton catalyst, such as iron(III) nitrate nonahydrate, to exhibit catalytic activity similar to that of the Fenton reaction and further increase the removal rate. 140 ppm of catalyst was added to the formulation of Example 5, and the Mo removal rate and SER were tested. After adding the catalyst, the removal rate increased by approximately 20% without compromising corrosion protection efficiency. Table 5 shows the SER at various oxidant concentrations using 140 ppm of catalyst. TIFF0007801373000005.tif83170

[0045] Part B - Ruthenium Polishing Examples Experimental equipment: All of the following removal rate experiments were performed on a Buehler Automet 250 benchtop polisher using 1.25" x 1.25" ruthenium PVD evaporation coupons at a platen speed of 100 RPM and a head speed of 60 RPM. A flow rate of 30 mL / min was maintained. Data was generated with a felt-type SUBA-1200 polishing pad. Removal rates were measured using 5-point characterization with a 4-point probe (ResMap). TIFF0007801373000006.tif128170

[0046] This series of experiments demonstrated that aluminum-coated titania particles reacted catalytically with the ruthenium surface to form RuO x - It has been shown that a passivation layer of 100% is formed on the surface of the abrasive grains, which is easily removed by friction between the abrasive grains and the pad.

[0047] The next set of experiments utilized titania abrasives coated with aluminum approximately 200 nm in size at a solids loading of 2.5%. TIFF0007801373000007.tif167170

[0048] The above data reflects operation above pH 6; below pH 6, toxic RuO4 (ruthenium tetroxide) may be formed. Also, as the pH increases, pad fouling decreases, decreasing rapidly above pH 9, with almost no fouling observed at pH 12.5. This is because at higher pHs, soluble RuO4 is produced instead of RuO2 and RuO4. - / RuO2 - This is thought to be due to the formation of ions.

[0049] Aspects In a first aspect, the present invention provides a method for producing a medicament for the treatment of a pulmonary arthritis, comprising: Liquid carrier; the particles are at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles; titania abrasive particles, wherein the coated titania abrasive particles have an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors A composition comprising:

[0050] In a second aspect, the invention provides the composition of the first aspect, wherein the coated titania abrasive particles are coated with alumina.

[0051] In a third aspect, the invention provides a composition of the first or second aspect, wherein the coated titania abrasive particles are coated with amorphous silica.

[0052] In a fourth aspect, the present invention provides a composition of any of the first, second or third aspects, wherein the corrosion inhibitor is a cationic surfactant.

[0053] In a fifth aspect, the present invention provides the composition of any one of the first to fourth aspects, wherein the corrosion inhibitor is selected from benzalkonium chloride and benzalkonium bromide.

[0054] In a sixth aspect, the present invention provides a composition of any one of the first to fifth aspects, wherein the composition has a pH of about 2 to about 5.

[0055] In a seventh aspect, the present invention provides a composition of any one of the first to sixth aspects, further comprising at least one oxidizing agent.

[0056] In an eighth aspect, the present invention provides the composition of the seventh aspect, wherein the oxidizing agent is selected from hydrogen peroxide and periodic acid.

[0057] In a ninth aspect, the present invention provides a method for chemical-mechanical polishing a substrate comprising a surface comprising at least one transition metal, the method comprising: The base material Liquid carrier; the particles are at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles; titania abrasive particles, wherein the coated titania abrasive particles have an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors contacting with a composition comprising: transferring the composition relative to the substrate; and grinding the substrate to remove a portion of the surface comprising at least one transition metal; The present invention provides a method comprising:

[0058] In a tenth aspect, the present invention provides the method of the ninth aspect, wherein the surface comprises molybdenum.

[0059] In an eleventh aspect, the present invention provides the method of the ninth aspect, wherein the surface comprises ruthenium.

[0060] In a twelfth aspect, the present invention provides a method of the ninth, tenth or eleventh aspect, wherein the pH is from about 2 to about 5.

[0061] In a thirteenth aspect, the invention provides the method of any one of the ninth through twelfth aspects, wherein the coated titania abrasive particles are coated with alumina.

[0062] In a fourteenth aspect, the invention provides the method of any one of the ninth through thirteenth aspects, wherein the coated titania abrasive particles are coated with amorphous silica.

[0063] In a fifteenth aspect, the present invention provides the method of any one of the ninth to fourteenth aspects, wherein the corrosion inhibitor is selected from benzalkonium chloride and benzalkonium bromide.

[0064] In a sixteenth aspect, the present invention provides a method for chemical mechanical polishing a substrate comprising a surface comprising at least one of molybdenum or ruthenium, the method comprising: The base material Liquid carrier; the particles are at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles; titania abrasive particles, wherein the coated titania abrasive particles have an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors contacting the composition with a composition comprising: transferring the composition relative to the substrate; and grinding the substrate to remove a portion of the surface containing at least one of molybdenum or ruthenium; The present invention provides a method comprising:

[0065] In a seventeenth aspect, the present invention provides a kit comprising components selected from components a., b. and c. as defined in any one of the first to eighth aspects in one or more containers.

[0066] While several illustrative embodiments of the present disclosure have thus been described, those skilled in the art will readily appreciate that still other embodiments may be made and used within the scope of the claims appended hereto. Numerous advantages of the present disclosure, which are the subject of this specification, have been set forth in the foregoing description. It will be understood, however, that this disclosure is in many respects merely illustrative. The scope of the present disclosure, of course, is defined in the language in which the appended claims are expressed.

Claims

1. 1. A composition for chemical mechanical polishing of a substrate comprising a surface comprising molybdenum, comprising: Liquid carrier; titania abrasive particles, the particles being at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles, the coated titania abrasive particles having an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors A composition comprising:

2. 10. The composition of claim 1, wherein the coated titania abrasive particles are coated with alumina.

3. The composition of claim 1 wherein the corrosion inhibitor is a cationic surfactant.

4. 4. The composition of claim 3, wherein the corrosion inhibitor is selected from benzalkonium chloride and benzalkonium bromide.

5. Liquid carrier; titania abrasive particles, the particles being at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles, the coated titania abrasive particles having an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors Including, The composition has a pH of about 2 to about 5.

6. 10. The composition of claim 1 or 5, further comprising at least one oxidizing agent.

7. 7. The composition of claim 6, wherein the oxidizing agent is selected from hydrogen peroxide and periodic acid.

8. 1. A method for chemical mechanical polishing a substrate comprising a surface comprising molybdenum, comprising: The substrate Liquid carrier; titania abrasive particles, the particles being at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles, the coated titania abrasive particles having an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors contacting with a composition comprising: transferring the composition relative to the substrate; and Grinding the substrate to remove a portion of the surface containing molybdenum A method comprising:

9. 1. A method for chemical mechanical polishing a substrate comprising a surface comprising at least one transition metal, comprising: The substrate Liquid carrier; titania abrasive particles, the particles being at least partially coated with alumina or amorphous silica to provide coated titania abrasive particles, the coated titania abrasive particles having an average diameter of about 50 nm to about 250 nm; and Corrosion inhibitors contacting with a composition comprising: transferring the composition relative to the substrate; and grinding the substrate to remove a portion of the surface comprising at least one transition metal; Including, The method wherein the pH is from about 2 to about 5.

10. 10. The method of claim 8 or 9, wherein the coated titania abrasive particles are coated with alumina.

11. 10. The method of claim 8 or 9, wherein the corrosion inhibitor is selected from benzalkonium chloride and benzalkonium bromide.

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