Polishing composition and method of use thereof

Abstract

A polishing composition, comprising an abrasive; a pH adjuster; a barrier film removal rate enhancer; a low-k removal rate inhibitor; an azole-containing corrosion inhibitor; and a ruthenium removal rate enhancer. A method of polishing a substrate, comprising the steps of: applying the polishing composition described herein to a surface of the substrate, wherein the surface comprises ruthenium or a hard mask material; contacting a pad with the surface of the substrate and moving the pad relative to the substrate.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the priority of U.S. Provisional Application No. 62 / 975,829, filed on February 13, 2020, the content of which is incorporated herein by reference in its entirety. Background Art

[0003] The continuous drive to further miniaturize devices through process, material, and integration innovations has been improving the chip performance of the semiconductor industry. Early material innovations included the introduction of copper to replace aluminum as the conductive material in interconnect structures; and the use of tantalum (Ta) / tantalum nitride (TaN) as a diffusion barrier to isolate non - conductive / insulating dielectric materials from the copper conductive material. Copper (Cu) was chosen as the interconnect material because of its low resistivity and excellent electromigration resistance.

[0004] However, as the topography of newer - generation chips shrinks, the multi - layer Cu / barrier layer / dielectric stack needs to become thinner and more conformal to maintain effective interconnect resistivity in the back - end - of - line (BEOL). Thinner copper and Ta / TaN barrier film solutions have problems with resistivity and flexibility during deposition. For example, with smaller dimensions and advanced manufacturing nodes, the resistivity continues to deteriorate exponentially, and the improvement in transistor circuit speed (in the front - end - of - line (FEOL)) is halved by the delay from the conductive Cu / barrier layer wiring (BEOL). Ruthenium (Ru) emerged as a major candidate material for liner materials, barrier layers, and conductive layers. Ruthenium not only has excellent anti - Cu diffusion properties against dielectric layers but also facilitates direct electro - filling of copper in small - size trenches without using a copper seed layer. In addition, ruthenium has also been studied as a material for vias to replace traditional tungsten (W) metal. Summary of the Invention

[0005] A summary of the invention is provided to introduce a selection of concepts that are further described below in the detailed description. The summary of the invention is not intended to identify key or essential features of the claimed invention, nor is it intended to be used as an aid in limiting the scope of the claimed invention.

[0006] As defined herein, unless otherwise specified, all percentages expressed are to be understood as weight percentages relative to the total weight of the polishing composition.

[0007] In one aspect, embodiments disclosed herein relate to a polishing composition comprising an abrasive; a pH adjuster; a barrier film removal rate enhancer; a low - k removal rate inhibitor; an azole - containing corrosion inhibitor; and a ruthenium removal rate enhancer.

[0008] In another aspect, embodiments disclosed herein relate to a polishing composition comprising an abrasive; a pH adjuster; an organic acid or its salts; a nonionic surfactant; an azole-containing corrosion inhibitor; and a compound selected from the group consisting of ammonium salts, thiocyanates, halide salts, nitrates, nitric acid, or mixtures thereof.

[0009] In yet another aspect, embodiments disclosed herein relate to a method of polishing a substrate (such as a substrate comprising ruthenium), comprising the steps of: applying the polishing composition described herein to a surface of the substrate, wherein the surface comprises ruthenium or a hard mask material; and contacting a pad with the surface of the substrate and moving the pad relative to the substrate.

[0010] Other aspects and advantages required will be apparent from the following description and the appended claims. DETAILED DESCRIPTION

[0011] Embodiments disclosed herein generally relate to compositions and methods of using such compositions to polish substrates that include at least a ruthenium portion and / or a hard mask portion (such as tungsten, carbide, nitrided ceramics (such as TiN), and their doped derivatives), and more specifically may include at least ruthenium, a hard mask, and a copper portion. The compositions disclosed herein can effectively remove ruthenium and / or hard mask materials while minimizing copper corrosion (e.g., minimizing surface roughness). For example, the compositions disclosed herein can be particularly useful for polishing advanced node films that include copper, ruthenium liners, hard mask materials (such as titanium and titanium-doped derivatives, tungsten and tungsten-doped derivatives (such as WB4), carbides (such as BC, B4C, TiC, SiC, and WC), boron-containing materials (such as B6O, BC2N, and AlMgB 14 ) and nitrided ceramic materials (such as SiN, TiN, BN), barrier layer materials (such as Ta, TaN), and dielectric materials (such as TEOS, low-k, ultra-low-k, etc.).

[0012] Many currently available CMP slurries are designed to remove materials that are more prevalent in older chips, such as the aforementioned copper and tungsten. However, in back-end-of-line (BEOL) applications in the semiconductor industry, ruthenium is being used as a liner material due to its good conductivity, deposition properties, and resistance to Cu diffusion. Unlike some other materials such as cobalt and copper, ruthenium is relatively chemically stable and does not deteriorate, and is difficult to remove during polishing. In addition, ruthenium systems are often used in conjunction with copper as a conductive layer. As mentioned above, copper is a relatively soft material and is therefore easy to remove. Copper is necessary for the function of many semiconductor devices, so if a CMP slurry that is too easy to strip or damage the copper layer or inlay is used, it may have a negative impact on the performance of the device product. Older CMP slurries may not be able to effectively remove ruthenium without causing harmful and unacceptable defects to copper, because copper is more susceptible to chemical corrosion. Therefore, less advanced slurries will exhibit unacceptable corrosion, wafer topography, and / or removal rate selectivity for one or more of the components in the multi-component substrate to be polished. In addition, more complex integration schemes may use a hard mask as an etch mask in conjunction with a Ru liner and a Cu conductive layer connection, which presents another material that the polishing slurry must be able to effectively remove.

[0013] As the use of multi-component integration schemes in semiconductor manufacturing increases and dimensions shrink, there is a market demand for CMP slurries that can effectively polish substrates including ruthenium, copper, and hard mask materials, with minimal copper corrosion and good removal rates and selectivity for all other components.

[0014] In one or more embodiments, the polishing compositions described herein include an abrasive; a pH adjuster; a barrier film removal rate enhancer; a low-k removal rate inhibitor; an azole-containing corrosion inhibitor; and a ruthenium removal rate enhancer. In one or more embodiments, the polishing composition may further include a chelating agent and / or an oxidizing agent. In one or more embodiments, the polishing composition according to the present disclosure may include from about 0.1 wt% to about 50 wt% of an abrasive, from about 0.01 wt% to about 10 wt% of a pH adjuster, from about 0.002 wt% to about 4 wt% of a barrier film removal rate enhancer, from about 0.0005 wt% to about 5 wt% of a low-k removal rate inhibitor, from about 0.0001 wt% to about 1 wt% of an azole-containing corrosion inhibitor, from about 0.0001 wt% to about 5 wt% of a ruthenium removal rate enhancer, and the balance in weight percentage (e.g., from about 20 wt% to about 99 wt%) of a solvent (e.g., deionized water). In one or more embodiments, the polishing composition may further include from about 0.001 wt% to about 1 wt% of a chelating agent and / or from about 0.001 wt% to about 5 wt% of an oxidizing agent.

[0015] In one or more embodiments, the present disclosure provides a concentrated polishing composition that can be diluted with water up to two-fold, or up to four-fold, or up to six-fold, or up to eight-fold, or up to ten-fold before use. In other embodiments, the present disclosure provides a point-of-use (POU) polishing composition for ruthenium-containing substrates, which comprises the above polishing composition, water, and optionally an oxidizing agent.

[0016] In one or more embodiments, the POU polishing composition can include from about 0.1 wt% to about 12 wt% of an abrasive, from about 0.01 wt% to about 5 wt% of a pH adjuster, from about 0.002 wt% to about 2 wt% of a barrier film removal rate enhancer, from about 0.0005 wt% to about 0.5 wt% of a low-k removal rate inhibitor, from about 0.0001 wt% to about 0.1 wt% of an azole-containing corrosion inhibitor, from about 0.0001 wt% to about 0.5 wt% of a ruthenium removal rate enhancer, optionally from about 0.001 wt% to about 5 wt% of an oxidizing agent, and from about 80 wt% to about 99 wt% of a solvent (e.g., deionized water). In one or more embodiments, the POU polishing composition can further include from 0.001 wt% to 0.1 wt% of a chelating agent.

[0017] In one or more embodiments, the concentrated polishing composition can include from about 1 wt% to about 50 wt% of an abrasive, from about 0.1 wt% to about 10 wt% of a pH adjuster, from about 0.02 wt% to about 4 wt% of a barrier film removal rate enhancer, from about 0.005 wt% to about 5 wt% of a low-k removal rate inhibitor, from about 0.001 wt% to about 1 wt% of an azole-containing corrosion inhibitor, from about 0.001 wt% to about 5 wt% of a ruthenium removal rate enhancer, and the remaining weight percentage (e.g., from about 20 wt% to about 98.5 wt%) of a solvent (e.g., deionized water). In one or more embodiments, the polishing composition can further include from about 0.01 wt% to about 1 wt% of a chelating agent and / or from about 0.01 wt% to about 5 wt% of an oxidizing agent.

[0018] In one or more embodiments, the polishing compositions described herein may include at least one (e.g., two or three) abrasive. In some embodiments, the at least one abrasive is selected from the group consisting of cationic abrasives, substantially neutral abrasives, and anionic abrasives. In one or more embodiments, the at least one abrasive is selected from the group consisting of alumina, silica, titania, ceria, zirconia, their co-formation products (i.e., co-formation products of alumina, silica, titania, ceria, or zirconia), coated abrasives, surface-modified abrasives, and mixtures thereof. In some embodiments, the at least one abrasive does not include ceria. In some embodiments, the at least one abrasive is of high purity and may have less than about 100 ppm of alcohol, less than about 100 ppm of ammonia, and less than about 100 parts per billion (ppb) of alkali metal cations such as sodium ions. Based on the total weight of the POU polishing composition, the content of the abrasive may be from about 0.1% to about 12% or any sub-range thereof (e.g., from about 0.5% to about 10%).

[0019] In some embodiments, the content of the at least one abrasive is at least about 0.1 wt% (e.g., at least about 0.5%, at least about 1%, at least about 2%, at least about 4%, at least about 5%, at least about 10%, at least about 12%, at least about 15%, or at least about 20%) to at most about 50 wt% (e.g., at most about 45%, at most about 40%, at most about 35%, at most about 30%, at most about 25%, at most about 20%, at most about 15%, at most about 12%, at most about 10%, or at most about 5%) of the polishing composition described herein.

[0020] In one or more embodiments, the polishing compositions described herein may include at least one (e.g., two or three) pH adjuster. In some embodiments, the at least one pH adjuster is selected from the group consisting of ammonium hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide, monoethanolamine, diethanolamine, triethanolamine, methylethanolamine, methyldiethanolamine, tetrabutylammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, ethyltrimethylammonium hydroxide, diethyldimethylammonium hydroxide, dimethyldipropylammonium hydroxide, benzyltrimethylammonium hydroxide, tris(2-hydroxyethyl)methylammonium hydroxide, choline hydroxide, and any combination thereof.

[0021] In some embodiments, the content of the at least one pH adjuster is at least about 0.01 wt% (e.g., at least about 0.05%, at least about 0.1%, at least about 0.5%, at least about 1%, at least about 2%, at least about 4%, at least about 5%, at least about 6%, or at least about 8%) to at most about 10 wt% (e.g., at most about 9%, at most about 8%, at most about 7%, at most about 6%, at most about 5%, at most about 4%, at most about 3%, at most about 2%, at most about 1%, at most about 0.5%, at most about 0.2%, or at most about 0.1%) of the polishing composition described herein.

[0022] In some embodiments, the pH value of the polishing composition can range from at least about 7 (e.g., at least about 7.5, at least about 8, at least about 8.5, at least about 9, at least about 9.5, at least about 10, at least about 10.5, at least about 11, at least about 11.5, or at least about 12) to at most about 14 (e.g., at most about 13.5, at most about 13, at most about 12.5, at most about 12, at most about 11.5, at most about 11, at most about 10.5, at most about 10, at most about 9.5, or at most about 9). Without wishing to be bound by theory, it is generally believed that a polishing composition having a pH below 7 will significantly increase the copper removal rate and corrosion; while a polishing composition having a pH above 14 will affect the stability of the suspended abrasive and will significantly increase the roughness and reduce the overall quality of the film polished by this composition. To obtain the desired pH, the relative concentrations of the components in the polishing composition described herein can be adjusted.

[0023] In one or more embodiments, the polishing composition described herein can include at least one (e.g., two or three) barrier film removal rate enhancers. In some embodiments, the at least one barrier film removal rate enhancer is an organic acid (such as carboxylic acid, amino acid, sulfonic acid, or phosphonic acid) or a salt thereof. In some embodiments, the barrier film removal rate enhancer can be an organic acid or a salt thereof selected from the group consisting of gluconic acid, lactic acid, citric acid, tartaric acid, malic acid, glycolic acid, malonic acid, formic acid, oxalic acid, acetic acid, propionic acid, peracetic acid, succinic acid, lactic acid, glycine, phenoxyacetic acid, diglycine, diglycolic acid, glyceric acid, methylglycine, alanine, histidine, valine, phenylalanine, proline, glutamine, aspartic acid, glutamic acid, arginine, lysine, tyrosine, benzoic acid, salts thereof, and mixtures thereof. Without wishing to be bound by theory, it is generally believed that organic acids or salts thereof (such as those described above) can be used as effective barrier film removal rate enhancers in the polishing composition described herein to improve the removal rate of barrier films (e.g., Ta or TaN films) in semiconductor substrates.

[0024] In some embodiments, the content of the barrier film removal rate enhancer is at least about 0.002 wt% (e.g., at least about 0.005%, at least about 0.01%, at least about 0.05%, at least about 0.1%, at least about 0.15%, at least about 0.2%, at least about 0.5%, at least about 1%, at least about 1.5%, or at least about 2%) to at most about 4 wt% (e.g., at most about 3.5%, at most about 3%, at most about 2.5%, at most about 2%, at most about 1.5%, or at most about 1%) of the polishing composition described herein.

[0025] In one or more embodiments, the polishing composition described herein may include at least one (e.g., two or three) low-k removal rate inhibitors. In some embodiments, the at least one low-k removal rate inhibitor is a nonionic surfactant. In one or more embodiments, the nonionic surfactant is selected from the group consisting of alkoxylated alcohols, alkoxylated alkylphenols, alkoxylated triphenylvinylphenols, alkoxylated sorbitan esters, polyalkylene oxides, polyoxyalkylene block copolymers, tetrahydroxy oligomers, alkoxylated diamines, and mixtures thereof. In one or more embodiments, the nonionic surfactant is a polymer having a number average molecular weight of at least about 500 g / mol, or at least about 1,000 g / mol, or at least about 2,500 g / mol, or at least about 5,000 g / mol, or at least about 7,500 g / mol, or at least about 10,000 g / mol. In one or more embodiments, the nonionic surfactant is a polymer having a number average molecular weight of at most about 1,000,000 g / mol, or at most about 750,000 g / mol, or at most about 500,000 g / mol, or at most about 250,000 g / mol, or at most 100,000 g / mol. In one or more embodiments, the alkoxylated groups of the alkoxylated nonionic surfactant are ethoxylated groups, propoxylated groups, or a combination of ethoxylated and propoxylated groups. Without wishing to be bound by theory, unexpectedly, nonionic surfactants such as those described above can be used as low-k removal rate inhibitors in the polishing compositions described herein to reduce or minimize the removal rate of low-k films (e.g., carbon-doped silicon oxide films) in semiconductor substrates.

[0026] In some embodiments, the content of the low k rate inhibitor is at least about 0.0005 wt% (e.g., at least about 0.001%, at least about 0.005%, at least about 0.01%, at least about 0.05%, at least about 0.1%, at least about 0.5%, at least about 1%, at least about 1.5%, at least about 2%, or at least about 3%) to at most about 5 wt% (e.g., at most about 4.5%, at most about 4%, at most about 3.5%, at most about 3%, at most about 2.5%, at most about 2%, at most about 1.5%, at most about 1%, at most about 0.5%, or at most about 0.1%) of the polishing composition described herein.

[0027] In one or more embodiments, the polishing composition described herein may include at least one (e.g., two or three) azole-containing corrosion inhibitor. In some embodiments, the at least one azole-containing corrosion inhibitor is selected from the group consisting of substituted or unsubstituted triazoles, substituted or unsubstituted tetrazoles, substituted or unsubstituted benzotriazoles, substituted or unsubstituted pyrazoles, and substituted or unsubstituted imidazoles. In one or more embodiments, the azole-containing corrosion inhibitor may be selected from the group consisting of 1,2,4-triazole, 1,2,3-triazole, tetrazole, benzotriazole, tolyltriazole, methylbenzotriazole (e.g., 1-methylbenzotriazole, 4-methylbenzotriazole, and 5-methylbenzotriazole), ethylbenzotriazole (e.g., 1-ethylbenzotriazole), propylbenzotriazole (e.g., 1-propylbenzotriazole), butylbenzotriazole (e.g., 1-butylbenzotriazole and 5-butylbenzotriazole), pentylbenzotriazole (e.g., 1-pentylbenzotriazole), hexylbenzotriazole (e.g., 1-hexylbenzotriazole and 5-hexylbenzotriazole), dimethylbenzotriazole (e.g., 5,6-dimethylbenzotriazole), chlorobenzotriazole (e.g., 5-chlorobenzotriazole), dichlorobenzotriazole (e.g., 5,6-dichlorobenzotriazole), chloromethylbenzotriazole (e.g., 1-(chloromethyl)-1H-benzotriazole), chloroethylbenzotriazole, phenylbenzotriazole, benzylbenzotriazole, aminotriazole, aminobenzimidazole, aminotetrazole, and mixtures thereof. In one or more embodiments, the composition may include benzotriazole and benzotriazole derivatives (e.g., substituted benzotriazoles). Without wishing to be bound by theory, it is generally believed that azole-containing corrosion inhibitors (such as those described above) can significantly reduce or minimize the removal rate of copper in semiconductor substrates.

[0028] In some embodiments, the content of the azole-containing corrosion inhibitor is at least about 0.0001 wt% (e.g., at least about 0.0002%, at least about 0.0005%, at least about 0.001%, at least about 0.002%, at least about 0.005%, at least about 0.01%, at least about 0.02%, at least about 0.05%, at least about 0.1%, at least about 0.2%, or at least about 0.5%) to at most about 1 wt% (e.g., at most about 0.8%, at most about 0.6%, at most about 0.5%, at most about 0.4%, at most about 0.2%, at most about 0.1%, at most about 0.05%, at most about 0.02%, at most about 0.01%, or at most about 0.005%) of the polishing composition described herein.

[0029] In one or more embodiments, the polishing composition described herein may include at least one (e.g., two or three) ruthenium removal rate enhancer. In some embodiments, the at least one ruthenium removal rate enhancer may include ammonium salts, thiocyanates, nitric acid or its salts, and halide salts. In some embodiments, the at least one ruthenium removal rate enhancer is selected from the group consisting of ammonium hydroxide, ammonium chloride, ammonium fluoride, ammonium bromide, ammonium sulfate, ammonium carbonate, ammonium bicarbonate, ammonium nitrate, ammonium phosphate, ammonium acetate, ammonium thiocyanate, potassium thiocyanate, sodium thiocyanate, nitric acid, sodium nitrate, potassium nitrate, rubidium nitrate, cesium nitrate, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, sodium chloride, potassium chloride, rubidium chloride, cesium chloride, and mixtures thereof.

[0030] In some embodiments, the content of the ruthenium removal rate enhancer may be from about 0.0001 wt% to about 5 wt% of the composition. In one or more embodiments, the ruthenium removal rate enhancer is at least about 0.0001 wt% (e.g., at least about 0.0002%, at least about 0.0005%, at least about 0.001%, at least about 0.002%, at least about 0.005%, at least about 0.01%, at least about 0.02%, at least about 0.05%, at least about 0.1%, at least about 0.2%, or at least about 0.5%) to at most about 5 wt% (e.g., at most about 4%, at most about 3%, at most about 2%, at most about 1%, at most about 0.8%, at most about 0.6%, at most about 0.5%, at most about 0.4%, at most about 0.2%, at most about 0.1%, at most about 0.05%, at most about 0.02%, at most about 0.01%, or at most about 0.005%) of the polishing composition described herein.

[0031] In one or more embodiments, the polishing compositions described herein may optionally include at least one (e.g., two or three) chelating agents. In some embodiments, the at least one optional chelating agent may be an amino-containing carboxylic acid (e.g., polyamino polycarboxylic acid) or phosphonic acid. In some embodiments, the chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid, iminodiacetic acid, N-hydroxyethyl-ethylenediaminetriacetic acid, nitrilotriacetic acid, diethylenetriaminepentaacetic acid, hydroxyethylethylenediaminetriacetic acid, triethylenetetraminehexaacetic acid, cyclohexanediaminetetraacetic acid, nitrilotrimethylphosphonic acid, ethylenediaminetetra(methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, diethylenetriaminepenta(methylenephosphonic acid), and combinations thereof. Without wishing to be bound by theory, it is generally believed that incorporating a chelating agent (such as those described above) into the polishing compositions described herein can significantly reduce or minimize defects observable on a semiconductor substrate (such as defects on the surface of a copper wafer).

[0032] In some embodiments, the content of the chelating agent is at least about 0.001 wt% (e.g., at least about 0.002%, at least about 0.005%, at least about 0.01%, at least about 0.02%, at least about 0.05%, at least about 0.1%, at least about 0.2%, or at least about 0.5%) to at most about 1 wt% (e.g., at most about 0.8%, at most about 0.6%, at most about 0.5%, at most about 0.4%, at most about 0.2%, at most about 0.1%, at most about 0.05%, at most about 0.02%, at most about 0.01%, or at most about 0.005%) of the polishing compositions described herein.

[0033] When diluting a concentrated slurry to form a POU slurry, an optional oxidizing agent (or oxidation reagent) may be added. The oxidizing agent is selected from the group consisting of hydrogen peroxide, periodic acid, metaperiodic acid, diperiodate, diperiodate, ammonium periodate, potassium periodate, sodium periodate, ammonium persulfate, iodic acid, iodate, perchloric acid, perchlorate, hydroxylamine, hydroxylamine salt, and any combination thereof. In one or more embodiments, the oxidizing agent may be hydrogen peroxide.

[0034] In some embodiments, the content of the oxidizing agent is at least about 0.001 wt% (e.g., at least about 0.002%, at least about 0.004%, at least about 0.005%, at least about 0.01%, at least about 0.025%, at least about 0.05%, at least about 0.075%, at least about 0.1%, at least about 0.5%, at least about 1%, or at least about 2%) to at most about 5 wt% (e.g., at most about 4.5%, at most about 4%, at most about 3.5%, at most about 3%, at most about 2.5%, at most about 2%, at most about 1.5%, at most about 1%, at most about 0.5%, or at most about 0.1%) of the polishing composition described herein. In some embodiments, without wishing to be bound by theory, it is generally believed that the oxidizing agent can help remove the hard mask material in the hard mask substrate-containing material.

[0035] In some embodiments, the polishing composition described herein may include a solvent (e.g., a main solvent), such as water. In some embodiments, the content of the solvent (e.g., water) is at least about 20 wt% (e.g., at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 92%, at least about 94%, at least about 95%, or at least about 97%) to at most about 99 wt% (e.g., at most about 98%, at most about 96%, at most about 94%, at most about 92%, at most about 90%, at most about 85%, at most about 80%, at most about 75%, at most about 70%, or at most about 65%) of the polishing composition described herein.

[0036] In one or more embodiments, an optional co-solvent (e.g., an organic solvent) can be used in the polishing composition (e.g., a POU or a concentrated polishing composition) of the present disclosure to assist in the dissolution of the azole corrosion inhibitor. In one or more embodiments, the co-solvent can be one or more alcohols, alkylene glycols, or alkylene glycol ethers. In one or more embodiments, the co-solvent includes one or more solvents selected from the group consisting of ethanol, 1-propanol, 2-propanol, n-butanol, propylene glycol, 2-methoxyethanol, 2-ethoxyethanol, propylene glycol propyl ether, dimethyl sulfoxide, and ethylene glycol.

[0037] In some embodiments, the content of the auxiliary solvent is at least about 0.0025 wt% (e.g., at least about 0.005%, at least about 0.01%, at least about 0.02%, at least about 0.05%, at least about 0.1%, at least about 0.2%, at least about 0.4%, at least about 0.6%, at least about 0.8%, or at least about 1%) to at most about 5 wt% (e.g., at most about 4%, at most about 3%, at most about 2%, at most about 1%, at most about 0.8%, at most about 0.6%, at most about 0.5%, or at most about 0.1%) of the polishing composition described herein.

[0038] In one or more embodiments, the polishing composition described herein may be substantially free of one or more specific components, such as organic solvents, pH adjusters, quaternary ammonium compounds (e.g., salts or hydroxides), amines, alkali metal salts (such as alkali metal hydroxides), fluorine-containing compounds, silicon-containing compounds such as silanes (e.g., alkoxysilanes), imines (e.g., amidines, such as 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) and 1,5-diazabicyclo[4.3.0]non-5-ene (DBN)), salts (e.g., halide salts or metal salts), polymers (e.g., cationic or anionic polymers), surfactants (e.g., cationic surfactants, anionic surfactants, or nonionic surfactants), plasticizers, oxidants (e.g., periodic acid), corrosion inhibitors (e.g., azole or non-azole corrosion inhibitors), and / or specific abrasives (e.g., cerium oxide abrasives, nonionic abrasives, surface-modified abrasives, or negatively / positively charged abrasives). The halide salts that can be excluded from the polishing composition include alkali metal halides (e.g., sodium halide or potassium halide) or ammonium halides (e.g., ammonium chloride), and can be fluorides, chlorides, bromides, or iodides. As used herein, "substantially free of" a component in the polishing composition means a component that is not deliberately added to the polishing composition. In some embodiments, the polishing composition described herein may have at most about 1000 ppm (e.g., at most about 500 ppm, at most about 250 ppm, at most about 100 ppm, at most about 50 ppm, at most about 10 ppm, or at most about 1 ppm) of one or more of the above components that the polishing composition is substantially free of. In some embodiments, the polishing composition described herein may be completely free of one or more of the above components.

[0039] The present disclosure also contemplates a method of using any of the above polishing compositions (e.g., a concentrate or a POU slurry). For the concentrate, the method may include the steps of diluting the concentrate to form a POU slurry (e.g., by at least a factor of two), and then contacting at least a surface comprising ruthenium and / or a hard mask material with the POU slurry. In some embodiments, an oxidizing agent may be added to the slurry before, after, or during dilution. For the POU slurry, the method includes the step of contacting at least a surface comprising ruthenium and / or a hard mask material with the slurry.

[0040] In one or more embodiments, the present disclosure is characterized by a polishing method that may include: applying a polishing composition according to the present disclosure to a substrate (e.g., a wafer) having at least ruthenium and / or a hard mask material on a surface thereof; and contacting a pad with the surface of the substrate and moving the pad relative to the substrate. In some embodiments, when the substrate includes at least one or more of silicon oxide, ruthenium, copper, a hard mask material, and / or a barrier layer material (e.g., Ta, TaN), the above method can effectively polish the substrate without significant corrosion or undesired removal rate selectivity. In one or more embodiments, the copper removal rate is less than about or less than about or less than about or less than about or less than about or less than about or less than about or less than about or less than about or less than about In one or more embodiments, the static etch rate (SER) of a 2 cm x 2 cm copper specimen incubated with the polishing composition at 45 °C for 5 minutes according to the present disclosure is less than about or less than about or less than about or less than about or less than about or less than about or less than about or less than about In one or more embodiments, the ruthenium removal rate is at least about or at least about or at least about or at least about or at least about or at least about or at least about In one or more embodiments, the ratio of the copper polish rate to the ruthenium polish rate (Cu:Ru) is at most about 35:1, or at most about 30:1, or at most about 25:1, or at most about 20:1, or at most about 15:1, or at most about 10:1, or at most about 5:1, or at most about 4:1, or at most about 3:1, or at most about 2.5:1, or at most about 2:1, or at most about 1.5:1, or at most about 1:1.

[0041] It should be noted that the term "silicon oxide" as used herein is intended to include both undoped and doped forms of silicon oxide. For example, in one or more embodiments, the silicon oxide may be doped with at least one dopant selected from the following: carbon, nitrogen (for silicon oxide), oxygen, hydrogen, or any other known dopant for silicon oxide. Some examples of silicon oxide include TEOS (tetraethyl orthosilicate), SiOC, SiOCN, SiOCH, SiOH, and SiON.

[0042] In some embodiments, the method of using the polishing composition described herein may further include producing a semiconductor device from the substrate treated with the polishing composition by one or more steps. For example, the substrate treated with the polishing composition described herein may be used to produce a semiconductor device using photolithography, ion implantation, dry / wet etching, plasma etching, deposition (e.g., PVD, CVD, ALD, ECD), wafer mounting, dicing, packaging, and testing.

[0043] The following specific examples should be construed as merely illustrative and in no way limiting to the remainder of the disclosure of the present invention. Without further elaboration, it is believed that one of ordinary skill in the art can make the fullest use of the present invention based on the description herein.

[0044] Examples

[0045] In these examples, polishing was performed in two polishing systems. One polishing system performed polishing on 300 mm wafers using an Ebara CMP polisher, a Fujibo soft pad, a downforce of 105 hPa, and a slurry flow rate of 100 to 500 mL / min. The second polishing system performed polishing on 200 mm wafers using an AMAT Mirra CMP polisher, a Fujibo soft pad, a downforce of 1.5 psi, and a slurry flow rate of 100 to 400 mL / min.

[0046] The general compositions used in the following examples are shown in Table 1 below. Specific details of the differences in the compositions tested will be further explained in detail when discussing the respective examples.

[0047] Table 1

[0048]

[0049]

[0050] Example 1

[0051] Table 2 below shows the removal rates for Ru, Cu, and Black Diamond 1 (BD-1) blank wafers when polished with Compositions 1-6. Except for the differences identified below and in Table 2, Compositions 1-6 contain the same components at the same concentrations. The BD-1 blank wafers are low-k dielectric materials (i.e., carbon-doped silicon oxide) coated on silicon wafers.

[0052] Composition 1 includes a Cu removal rate inhibitor (Cu RRI), which is an azole-containing corrosion inhibitor. Compositions 2-5 each include different concentrations of a ruthenium removal rate enhancer (Ru RRE), as shown in Table 2. Compositions 6 and 7 include the Ru RRE and two Cu removal rate inhibitors (i.e., Cu RRI-1 and Cu RRI-2), both of which are azole-containing corrosion inhibitors. Composition 8 includes the Ru RRE and only one Cu RRI.

[0053] This result unexpectedly shows that the addition of the Ru RRE increases the Ru removal rate to an acceptable range of about 30 Å / min. In addition, the Cu removal rate, which increases with the addition of the Ru RRE, can be appropriately controlled by the addition of a second Cu RRI. Furthermore, this result shows that the removal rate of BD-1 is not significantly affected by the addition of the Ru RRE and Cu-RRI-2.

[0054] Table 2

[0055]

[0056] RR = Removal Rate, SER = Static Etch Rate

[0057] Although only a few exemplary embodiments have been described in detail above, those skilled in the art will readily understand that many modifications to the exemplary embodiments are possible without substantially departing from the present invention. Accordingly, all such modifications are intended to be included within the scope of the present invention as defined by the following claims.

Claims

1. A polishing composition, comprising: an abrasive, wherein, The content of the abrasive is 0.1% to 50% by weight of the composition; A pH adjuster, wherein the content of the pH adjuster is 0.01% to 10% by weight of the composition; A barrier film removal rate enhancer, wherein the content of the barrier film removal rate enhancer is 0.002% to 4% by weight of the composition, and the barrier film removal rate enhancer is an organic acid or its salt, and the organic acid is selected from the group consisting of gluconic acid, lactic acid, citric acid, tartaric acid, malic acid, glycolic acid, malonic acid, formic acid, oxalic acid, acetic acid, propionic acid, peracetic acid, succinic acid, glycine, phenoxyacetic acid, diglycine, diglycolic acid, glyceric acid, methylglycine, alanine, histidine, valine, phenylalanine, proline, glutamine, aspartic acid, glutamic acid, arginine, lysine, tyrosine, benzoic acid, and mixtures thereof; A low-k removal rate inhibitor, wherein the content of the low-k removal rate inhibitor is 0.0005% to 5% by weight of the composition, and the low-k removal rate inhibitor is a nonionic surfactant, and the nonionic surfactant is selected from the group consisting of alkoxylated alcohols, alkoxylated alkylphenols, alkoxylated triphenylvinylphenols, alkoxylated sorbitan esters, polyalkylene oxides, tetrahydroxy oligomers, alkoxylated diamines, and mixtures thereof; An azole-containing corrosion inhibitor, wherein the content of the azole-containing corrosion inhibitor is 0.0001% to 1% by weight of the composition; A ruthenium removal rate enhancer, wherein the content of the ruthenium removal rate enhancer is 0.0001% to 5% by weight of the composition, and the ruthenium removal rate enhancer is selected from the group consisting of ammonium hydroxide, ammonium chloride, ammonium fluoride, ammonium bromide, ammonium sulfate, ammonium carbonate, ammonium bicarbonate, ammonium nitrate, ammonium phosphate, ammonium acetate, ammonium thiocyanate, potassium thiocyanate, sodium thiocyanate, nitric acid, sodium nitrate, potassium nitrate, rubidium nitrate, cesium nitrate, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, sodium chloride, potassium chloride, rubidium chloride, cesium chloride, and mixtures thereof; and A chelating agent, wherein the content of the chelating agent is 0.001% to 1% by weight of the composition, and the chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid, N-hydroxyethyl-ethylenediaminetriacetic acid, nitrilotriacetic acid, diethylenetriaminepentaacetic acid, hydroxyethylethylenediaminetriacetic acid, triethylenetetraminehexaacetic acid, cyclohexanediaminetetraacetic acid, nitrilotrimethylphosphonic acid, ethylenediaminetetra(methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, diethylenetriaminepenta(methylenephosphonic acid), and combinations thereof.

2. The polishing composition according to claim 1, wherein, The abrasive is selected from the group consisting of alumina; silica; titanium dioxide; cerium oxide; zirconium oxide; co-formed products of alumina, silica, titanium dioxide, cerium oxide, or zirconium oxide, coated abrasives, surface-modified abrasives, and mixtures thereof.

3. The polishing composition according to claim 1, wherein, The content of the abrasive is 1% to 40% by weight of the composition.

4. The polishing composition according to claim 1, wherein, The content of the barrier film removal rate enhancer is 0.01% to 3% by weight of the composition.

5. The polishing composition according to claim 1, wherein, The content of the low-k removal rate inhibitor is 0.005 wt% to 4 wt% of the composition.

6. The polishing composition according to claim 1, wherein, The azole-containing corrosion inhibitor is selected from the group consisting of triazole, tetrazole, benzotriazole, tolyltriazole, ethylbenzotriazole, propylbenzotriazole, butylbenzotriazole, amylbenzotriazole, hexylbenzotriazole, dimethylbenzotriazole, chlorobenzotriazole, dichlorobenzotriazole, chloromethylbenzotriazole, chloroethylbenzotriazole, phenylbenzotriazole, benzylbenzotriazole, aminotriazole, aminobenzimidazole, pyrazole, imidazole, aminotetrazole, and mixtures thereof.

7. The polishing composition according to claim 1, wherein, The content of the azole-containing corrosion inhibitor is 0.0005 wt% to 0.6 wt% of the composition.

8. The polishing composition according to claim 1, wherein, The pH adjuster is selected from the group consisting of ammonium hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide, monoethanolamine, diethanolamine, triethanolamine, methylethanolamine, methyldiethanolamine, tetrabutylammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, ethyltrimethylammonium hydroxide, diethyldimethylammonium hydroxide, dimethyldipropylammonium hydroxide, benzyltrimethylammonium hydroxide, tris(2-hydroxyethyl)methylammonium hydroxide, choline hydroxide, and any combination thereof.

9. The polishing composition according to claim 1, wherein, The content of the pH adjuster is 0.1 wt% to 8 wt% of the composition.

10. The polishing composition according to claim 1, wherein, The content of the ruthenium removal rate enhancer is 0.0005 wt% to 3 wt% of the composition.

11. The polishing composition according to claim 1, wherein, The content of the chelating agent is 0.005 wt% to 0.6 wt% of the composition.

12. The polishing composition according to claim 1, further comprising an oxidizing agent selected from the group consisting of hydrogen peroxide, periodic acid, metaperiodic acid, diperiodic acid, diperiodic acid, ammonium periodate, potassium periodate, sodium periodate, ammonium persulfate, iodic acid, iodate, perchloric acid, perchlorate, hydroxylamine, hydroxylamine salt, and any combination thereof.

13. The polishing composition according to claim 1, wherein, The composition comprises: the abrasive in an amount of 1 wt% to 40 wt% of the composition; the pH adjuster in an amount of 0.1 wt% to 8 wt% of the composition; the barrier film removal rate enhancer in an amount of 0.001 wt% to 3 wt% of the composition; the low-k removal rate inhibitor in an amount of 0.005 wt% to 4 wt% of the composition; the azole-containing corrosion inhibitor in an amount of 0.0005 wt% to 0.6 wt% of the composition; and the ruthenium removal rate enhancer in an amount of 0.0005 wt% to 3 wt% of the composition; and the chelating agent in an amount of 0.005 wt% to 0.6 wt% of the composition.

14. The polishing composition according to claim 1, wherein, The pH of the composition is 7 to 14.

15. A method of polishing a substrate, comprising the following steps: Applying the polishing composition according to any one of claims 1 to 14 to the surface of the substrate, wherein the surface comprises ruthenium or a hard mask material; and Bringing a pad into contact with the surface of the substrate and moving the pad relative to the substrate.

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