KR20230099021A - Cmp slurry composition for polishing metal - Google Patents

Abstract

The present invention relates to an abrasive slurry composition for metal polishing, comprising: abrasive particles; dishing improvers; and an oxidizing agent; and wherein the dishing improver has a weight average molecular weight (m _W ) of 800 or more and is a carboxylic acid-containing polymer.

Description

Polishing slurry composition for metal polishing {CMP SLURRY COMPOSITION FOR POLISHING METAL}

The present invention relates to a polishing slurry composition for metal polishing.

In recent years, chemical mechanical polishing (CMP) processes of various thin films constituting devices have been required in the semiconductor and display industries. A chemical mechanical polishing (CMP) process refers to a process of polishing a surface of a semiconductor wafer flat using a slurry containing an abrasive and various compounds while rotating in contact with a polishing pad. In general, it is known that in a metal polishing process, a process of forming a metal oxide (mO _x ) by an oxidizing agent and a process of removing the formed metal oxide by abrasive particles are repeatedly performed. In the polishing process of metal, the importance of reducing metal dishing, metal erosion and metal loss is increasing more and more, and at the same time, the polishing slurry composition must maintain a high removal rate, high selectivity to barrier materials and low defects. do.

In a process of polishing a metal layer, which is widely used as a wiring of a semiconductor device, an insulating film or a pattern such as a trench may be formed under the metal layer. In this case, high polishing selectivity between the metal layer and the insulating film is required in the CMP process, and a continuous polishing process is performed. If the selectivity of the slurry is too high, the target layer is excessively removed and recesses occur, or the insulating layer or the barrier layer collapses due to the physical action of the abrasive particles. The above-mentioned recess and erosion phenomena act as defects in wide-area planarization within a wafer, and as the defects accumulate according to stacking, they may appear as defects in a device.

In a semiconductor device, molybdenum (Mo) metal is initially used in excess, and a molybdenum polishing process is required to achieve surface properties suitable for semiconductor manufacturing. Polishing of metallic molybdenum surfaces often requires multiple steps to obtain the desired surface finish, which means multiple machines and/or parts and abrasive replacements that can adversely affect machining time for each part; It is necessary to develop a polishing slurry composition capable of improving defects such as dishing and erosion when polishing a molybdenum metal pattern film.

The above background art is possessed or acquired by the inventor in the process of deriving the disclosure of the present application, and cannot necessarily be said to be known art disclosed to the general public prior to the present application.

In order to solve the above problems, the present invention is to provide a polishing slurry composition for metal polishing, which can secure polishing performance of a metal film (eg, metal pattern film) substrate and improve dishing and erosion.

However, the problem to be solved by the present invention is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to one embodiment of the present invention, abrasive particles; dishing improvers; and an oxidizing agent; and wherein the dishing improver has a weight average molecular weight (M _W ) of 800 or more and is a carboxylic acid-containing polymer.

According to one embodiment of the present invention, the polymer includes a water-soluble polymer containing carboxylic acid, a copolymer thereof, or both, and the polymer includes poly acrylic acid, poly maleic acid acid), poly methacrylic acid, poly butadiene-co-maleic acid, poly acrylic acid-co-maleic acid, polyacrylamide (Polyacrylamide), polyacrylamide-co-acylic acid, polycarboxylic acid, poly(acrylic acid-maleic acid), poly(acrylonitrile-butadiene-acrylic acid), poly(acrylonitrile- Butadiene-methacrylic acid), poly(acrylic acid-co-maleic acid), poly(methyl methacrylate-co-methacrylic acid), poly(N-isopropylacrylamide- co-methacrylic acid) (poly(N-isopropylacrylamide-co-methacrylic acid)), poly(N-isopropylacrylamide-co-octadecyl acrylate) (poly(N-isopropylacrylamide-co-methacrylic acid) acid-co-octadecyl acrylate), poly(tert-butyl acrylate-co-ethyl acrylate-co-methacrylic acid), poly(methyl methacrylate acrylate) (poly(methyl methacrylate)), methyl methacrylate polymer-methyl methacrylate copolymer (methacrylic acid - methylmethacrylate copolymer), poly(methyl vinyl ether-alt-maleic acid) (poly(methyl vinyl ether-alt -maleic acid)), poly(styrene-alt-maleic acid) sodium salt solution, poly(4-styrenesulfonic acid-co-maleic acid) co-maleic acid) sodium salt), poly(styrene-co-maleic acid), partial isobutyl ester (poly(styrene-co-maleic acid), partial isobutyl ester), poly[(isobutylene-alt-maleic acid) , ammonium salt)-co-(isobutylene-alt-maleic anhydride)](poly[(isobutylene-alt-maleic acid, ammonium salt)-co-(isobutylene-alt-maleic anhydride)], poly(methyl vinyl ether -Alt-maleic acid monoethyl ester) solution (poly(methyl vinyl ether-alt-maleic acid monoethyl ester) solution), polyacrylic acid/sulfonic acid copolymer, polysulfonic acid/acrylamide copolymer, polyacrylamidemethylpropanesulfonic acid, poly At least one repeating unit of acrylic acid/styrene copolymer, polyacrylic acid, polymethacrylic acid and polymaleic acid selected from the group consisting of polypropylene oxide methacrylic acid, polypropylene oxide acrylic acid, polyethylene oxide methacrylic acid and polyethylene oxide acrylic acid copolymers comprising one or more repeating units; It may include at least one selected from the group consisting of.

According to one embodiment of the present invention, the dishing improver may be 0.001 wt% to 0.1 wt% of the polishing slurry composition.

According to one embodiment of the present invention, the abrasive particles, metal oxide; and metal oxides coated with organic or inorganic materials; or both, and the metal oxide may include at least one selected from the group consisting of silica, ceria, zirconia, alumina, titania, barium, titania, germania, mangania, and magnesia.

According to one embodiment of the present invention, the abrasive particles include self-assembly of fine particles, colloidal particles, or both, and the abrasive particles include primary particles of 5 nm to 150 nm, 30 nm to 300 nm nm secondary particles.

According to one embodiment of the present invention, the abrasive particles may be 0.1% to 10% by weight of the polishing slurry composition.

According to one embodiment of the present invention, the oxidizing agent is hydrogen peroxide, urea hydrogen peroxide, urea, percarbonate, periodic acid, periodate, perchloric acid, perchlorate, perbromic acid, perbromate, perboric acid, perborate, permanganic acid Potassium permanganate, sodium perborate, permanganic acid, permanganate, persulfate, bromate, chlorite, chlorate, chromate, dichromate, chromium compound ( Chromium Compound), iodate, iodic acid, ammonium persulfate, benzoyl peroxide, calcium peroxide, barium peroxide, sodium peroxide, dioxygenyl, ozone, ozonide, nitrate ( Nitrate, Hypochlorite, Hypohalite, Chromium trioxide, Pyridinium chlorochromate, Nitrous Oxide, Monopersulfate salt, Dipersulfate salt And it may include at least one selected from the group consisting of sodium peroxide.

According to one embodiment of the present invention, the oxidizing agent may be 0.0001% to 5% by weight of the polishing slurry composition.

According to one embodiment of the present invention, amino acids; may further include.

According to one embodiment of the present invention, the amino acid is lysine, methionine, cysteine, tyrosine, glycine, alanine, serine, phenylalanine, threonine, valine, leucine, isoleucine, proline, histidine, lysine, arginine, aspartic acid, tryptophan, Including at least one selected from the group consisting of glutamine and asparagine,

According to one embodiment of the present invention, the mixing ratio (w/w) of sulfur-containing amino acids to non-sulfur-containing amino acids in the amino acids may be 1:4 to 1:1.

According to one embodiment of the present invention, the amino acid may be 0.001% to 1% by weight of the polishing slurry composition.

According to one embodiment of the present invention, an iron-containing catalyst; may further include.

According to one embodiment of the present invention, the iron-containing catalyst is an iron-containing compound or an iron ion, and includes iron (II or III) nitrate; iron sulfate (II or III); iron (II or III) halides including fluoride, chloride, bromide and iodide; organic ferric (II and III) compounds such as iron perchlorates, perchlorates, perbromates and periodates, and acetates, acetylacetonates, citrates, gluconates, oxalates, phthalates, and succinates; It may include at least one selected from the group consisting of.

According to one embodiment of the present invention, the iron-containing catalyst may be 0.0001% to 1% by weight of the polishing slurry composition.

According to one embodiment of the present invention, the pH of the polishing slurry composition may have a range of 1 to 12.

According to an embodiment of the present invention, in the polishing slurry composition, the film to be polished may be a metal film, and the metal film may include at least one selected from the group consisting of a metal, a metal nitride, a metal oxide, and a metal alloy.

According to an embodiment of the present invention, the metal, metal nitride, metal oxide and metal alloy are indium (In), tin (Sn), silicon (Si), titanium (Ti), vanadium (V), Dolium (Gd), Gallium (Ga), Manganese (mn), Iron (Fe), Cobalt (Co), Copper (Cu), Zinc (Zn), Zirconium (Zr), Hafnium (Hf), Aluminum (Al), It may contain one or more selected from the group consisting of niobium (Nb), nickel (Ni), chromium (Cr), molybdenum (mo), tantalum (Ta), ruthenium (Ru), and tungsten (W). .

According to an embodiment of the present invention, the polishing rate of the polishing slurry composition for the polishing target film may be 500 Å/min or more.

The present invention can improve dishing and erosion on a metal film (eg, metal pattern wafer) during a polishing process on a metal film (eg, metal pattern wafer) (eg, molybdenum pattern wafer). It is to provide an abrasive slurry composition with

The present invention can provide a polishing slurry composition that has low etch rate characteristics or can control the etch rate and includes a long chain polymer.

According to the present invention, polishing characteristics can be controlled according to an etching rate when polishing a metal film (eg, a metal pattern wafer).

The present invention provides a slurry composition for metal polishing capable of maximally suppressing the occurrence of defects such as dishing and/or erosion in a pattern during and/or after polishing while securing a high polishing rate for a metal film quality, for example, a tungsten film quality. can provide.

The present invention can provide a slurry composition for metal polishing with excellent polishing performance for a metal film, which is a film to be polished, and significantly improved storage stability.

1 is a graph showing polishing rates, dishing, and erosion measured in a CMP process of polishing slurry compositions prepared in Examples and Comparative Examples according to an embodiment of the present invention.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, since various changes can be made to the embodiments, the scope of the patent application is not limited or limited by these embodiments. It should be understood that all changes, equivalents or substitutes to the embodiments are included within the scope of rights.

Terms used in the examples are used only for descriptive purposes and should not be construed as limiting. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present application, they should not be interpreted in an ideal or excessively formal meaning. don't

In addition, in the description with reference to the accompanying drawings, the same reference numerals are assigned to the same components regardless of reference numerals, and overlapping descriptions thereof will be omitted. In describing the embodiment, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the embodiment, the detailed description will be omitted.

In addition, in describing the components of the embodiment, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the corresponding component is not limited by the term. When an element is described as being “connected”, “coupled” or “connected” to another element, the element may be directly connected or connected to the other element, but there may be another element between the elements. It should be understood that may be "connected", "coupled" or "connected".

Components included in one embodiment and components including common functions will be described using the same names in other embodiments. Unless stated to the contrary, descriptions described in one embodiment may be applied to other embodiments, and detailed descriptions will be omitted to the extent of overlap.

The present invention relates to a polishing slurry composition, and according to an embodiment of the present invention, the polishing slurry composition includes abrasive particles; dishing improvers; and an oxidizing agent; can include

According to one embodiment of the present invention, the abrasive particles, the abrasive particles, metal oxide; and metal oxides coated with organic or inorganic materials; or both, and the metal oxide may include at least one selected from the group consisting of silica, ceria, zirconia, alumina, titania, barium, titania, germania, mangania, and magnesia. The abrasive particles provide high dispersion stability, and can implement high polishing characteristics while minimizing defects such as scratches by easily polishing a polishing target film, for example, a metal film.

As an example of the present invention, the abrasive particles are self-assembly of fine particles and may be porous particles.

As an example of the present invention, the abrasive particles may be dispersed in a colloidal state.

As an example of the present invention, the abrasive particles may include self-assembly of fine particles, colloidal particles, or both.

As an example of the present invention, the abrasive particles may exhibit a cationic surface charge by coating with organic and/or inorganic materials, surface substitution, or both. For example, the colloidal silica abrasive particles control the silica surface charge through the type of substituents on the surface of the silica particles, for example, substitution of cations such as NH ₃ ⁺ , control of the density (or number) of substituents, and the like. can do. For example, the cationic surface charge of the colloidal silica abrasive particles is 8 mV or more at pH 1 to 6 in a liquid carrier; 10 mV or higher; 15 mV or higher; Alternatively, it may exhibit a positive charge zeta potential of 40 mV or more.

As an example of the present invention, the abrasive particles are not particularly limited as long as the metal oxide particle manufacturing method is known in the art of the present invention, but is preferably a hydrothermal synthesis method, a sol-gel method, a precipitation method, a coprecipitation method, or a hydrothermal synthesis method. ), filtering method, aging method, spray drying method, thermal evaporation method, etc. may be used. The abrasive particles may include those produced by a liquid phase method, but are not limited thereto. The liquid phase method includes a sol-gel method in which abrasive particle precursors undergo a chemical reaction in an aqueous solution to grow crystals to obtain fine particles, a coprecipitation method in which abrasive particle ions are precipitated in an aqueous solution, and a hydrothermal method in which abrasive particles are formed under high temperature and high pressure. It may be prepared by applying a synthetic method or the like. The abrasive particles produced by the liquid phase method can be dispersed so that the surface of the abrasive particles has a positive charge.

As an example of the present invention, the abrasive particles may include at least one selected from the group consisting of a spherical shape, a prismatic shape, a needle shape, and a plate shape.

As an example of the present invention, the specific surface area of the abrasive particles is 31 m ² /g or more; 40 m ² /g or more; 31 m ² /g to 200 m ² /g; or 30 m ² /g to 150 m ² /g, and if it is within the above specific surface area range, a sufficient area of contact with the polishing target film is secured to provide a high level of polishing speed, and scratch and dishing on the surface of the polishing target film occurrence can be reduced. The specific surface area can be measured by the Brunauer-Emmett-Teller (BET) method. For example, it can be measured by the BET 6-point method by the nitrogen gas adsorption distribution method using a porosimetry analyzer (Bell Japan Inc, Belsorp-II mini).

As an example of the present invention, the primary particle size of the abrasive particles may be 5 nm to 150 nm, and the secondary particle size may be 30 nm to 300 nm. The measurement of the average particle diameter of the abrasive particles is an average value of the particle diameters of a plurality of particles within a field of view that can be measured by scanning electron microscopy, BET analysis or dynamic light scattering. In the size of the primary particles, it should be 150 nm or less in order to secure particle uniformity, and if it is less than 5 nm, the polishing rate may be lowered. When the size of the secondary particles is less than 30 nm, excessive generation of small particles due to milling reduces detergency, and excessive defects occur on the surface of substrates, wafers, etc. used in the polishing process, and exceeds 300 nm In the case of excessive polishing, it is difficult to control the selectivity, and dishing, erosion, and surface defects may occur. For example, the abrasive particles include first particles having a size of 10 nm to 50 nm and second particles having a size of greater than 50 nm to 100 nm, and the mixing ratio (mass ratio) of the first particles to the second particles is 1:0.1 to 10 days. The size may mean a diameter, length, thickness, etc. according to the shape of the particle.

As an example of the present invention, as the abrasive particles, in addition to particles of a single size, mixed particles having a multi-dispersion type particle distribution may be used. For example, two types of abrasive particles having different average particle sizes are mixed to have a bimodal particle distribution, or three types of abrasive particles having different average particle sizes are mixed to form a particle size distribution showing three peaks. may have Alternatively, four or more types of abrasive particles having different average particle sizes may be mixed to form a polydisperse particle distribution. By mixing relatively large abrasive particles and relatively small abrasive particles, it has better dispersibility and an effect of reducing scratches on the wafer surface can be expected.

As an example of the present invention, the abrasive particles may be monocrystalline, but are not limited thereto. When monocrystalline abrasive particles are used, a scratch reduction effect can be achieved compared to polycrystalline abrasive particles, dishing can be improved, and cleaning properties after polishing can be improved.

As an example of the present invention, the abrasive particles, 0.0001% to 10% by weight of the slurry composition; 0.001% to 5% by weight; Or it may be included in 0.1% by weight to 5% by weight. If it is within the above range, it is possible to implement a desired polishing rate and/or adjust the polishing rate according to the film to be polished (eg, metal film) to realize the desired selectivity, and if the slurry composition is less than 0.5% by weight, the polishing rate is reduced, and if it exceeds 10% by weight, the number of abrasive particles remaining on the surface of the polishing target film (eg, metal film) may increase due to the increase in the content of the abrasive particles, dishing and / Alternatively, secondary defects such as erosion may occur.

According to one embodiment of the present invention, the dishing improver includes a polymer containing at least one carboxyl group in a repeated unit structure, which corresponds to a water-soluble polymer containing carboxylic acid. In addition, the polymer may include a polymer including at least one repeating unit of polyacrylic acid, polymethacrylic acid, polymethacrylate, and polyacrylamide, a copolymer, or both. The polymer may control an etching rate during a polishing process of a film to be polished (eg, a metal film), and improve dishing, erosion, and the like of the film. For example, the polymer is polyacrylic acid, polymaleic acid, polyacrylamide, polymethacrylic acid, polybutadiene/maleic acid copolymer (poly butadiene-co -maleic acid), polyacrylic acid/maleic acid copolymer (poly acrylic acid-co-maleic acid), polyacrylamide/acrylic acid copolymer (poly acrylamid-co-acylic acid), polycarboxylic acid, poly(acrylic acid-maleic acid) ), poly(acrylonitrile-butadiene-acrylic acid), poly(acrylonitrile-butadiene-methacrylic acid), poly(acrylic acid-co-maleic acid), poly(methyl methacrylate-co-methacrylic acid) (poly (methyl methacrylate-co-methacrylic acid), poly(N-isopropylacrylamide-co-methacrylic acid), poly(N-isopropylacrylamide-co-methacrylic acid) Acrylic acid-co-octadecyl acrylate) (poly(N-isopropylacrylamide-co-methacrylic acid-co-octadecyl acrylate)), poly(tert-butyl acrylate-co-ethylacrylic-co-methacrylic acid (poly(tert -butyl acrylate-co-ethyl acrylate-co-methacrylic acid), poly(methyl methacrylate), methyl methacrylate polymer-methyl methacrylate copolymer, poly(methyl vinyl ether-alt-maleic acid), poly(styrene-alt-maleic acid) sodium salt solution, poly( 4-styrenesulfonic acid-co-maleic acid (poly(4-styrenesulfonic acid-co-maleic acid) sodium salt), poly(styrene-co-maleic acid), partial isobutyl ester (poly(styrene-co-maleic acid) acid), partial isobutyl ester), poly[(isobutylene-alt-maleic acid, ammonium salt)-co-(isobutylene-alt-maleic anhydride)](poly[(isobutylene-alt-maleic acid, ammonium salt )-co-(isobutylene-alt-maleic anhydride)], poly(methyl vinyl ether-alt-maleic acid monoethyl ester) solution, polyacrylic acid/sulfonic acid copolymer, polysulfonic acid/acrylamide copolymer, polyacrylamidemethylpropanesulfonic acid, polyacrylic acid/styrene copolymer, polyacrylic acid, polymethacrylic acid, and polymaleic acid, and at least one repeating unit of polypropylene oxide = methacrylic acid, a copolymer comprising at least one repeating unit selected from the group consisting of polypropylene oxide acrylic acid, polyethylene oxide methacrylic acid, and polyethylene oxide acrylic acid; And it may include at least one selected from the group consisting of salts thereof. The salt is selected according to the counter ion, and may be, for example, an ammonium salt or an alkali metal salt.

According to one embodiment of the present invention, the molecular weight (weight average molecular weight) of the polymer is 800 or more; over 1000; over 1500; 800 to 1500; Or it may be 3000 to 20,000. Preferably, having a long chain having a high half-atomic weight (eg, degree of polymerization) can prevent damage to the surface of the film. If it is out of the above range, the dispersibility of the slurry composition is lowered, the stability is not good, the etching rate is difficult to control, or the surface of the film to be polished (eg, metal film) after the polishing process Increases occurrence of erosion, dishing, etc. can do.

According to one embodiment of the present invention, the dishing improver may be included in an amount of 0.001 wt % to 0.1 wt % in the polishing slurry composition. When it is included within the above range, the selectivity for the metal film quality, eg, the metal film quality and the insulating film quality, can be implemented at an appropriate level. In addition, the planarization process may be performed by adjusting the polishing selectivity of the metal film. In addition, by adjusting the polishing selectivity, surface defects and the like can be minimized and excellent flatness can be provided after the polishing process. If the content is less than 0.001% by weight, it is difficult to obtain the desired polishing rate and the effect of improving dishing or erosion in the pattern, and if it exceeds 0.1% by weight, a condensation reaction between polymers occurs and secondary problems such as pattern profile change can cause

According to an embodiment of the present invention, the oxidizing agent may induce oxidation of the polishing target film to provide an appropriate polishing rate, and may be included in an amount of 0.0001% to 5% by weight in the polishing slurry composition. When it is within the above range, it is possible to provide an appropriate polishing rate for the polishing target film and prevent corrosion, erosion, and hardening of the polishing target film due to an increase in the content of the oxidizing agent.

According to one embodiment of the present invention, the oxidizing agent is hydrogen peroxide, urea hydrogen peroxide, urea, percarbonate, periodic acid, periodate, perchloric acid, perchlorate, perbromic acid, perbromate, perboric acid, perborate, permanganic acid Potassium permanganate, sodium perborate, permanganic acid, permanganate, persulfate, bromate, chlorite, chlorate, chromate, dichromate, chromium compound ( Chromium Compound), iodate, iodic acid, ammonium persulfate, benzoyl peroxide, calcium peroxide, barium peroxide, sodium peroxide, dioxygenyl, ozone, ozonide, nitrate ( Nitrate, hypochlorite, hypohalite, chromium trioxide, pyridinium chlorochromate, nitrous oxide, sulfate, potassium thiosulfate (potassium persulfate, K ₂ S ₂ O ₈ ), monopersulfate (eg KHSO ₅ ) salts, dipersulfate (eg KHSO ₄ and K ₂ SO ₄ ) salts, urea peroxide and sodium peroxide. It may include at least one selected from the group consisting of.

According to one embodiment of the present invention, the polishing slurry composition may further include at least one or more of a polishing accelerator, a catalyst, an amino acid, and a pH adjuster.

According to one embodiment of the present invention, the amino acid is lysine, methionine, cysteine, tyrosine, glycine, alanine, serine, phenylalanine, threonine, valine, leucine, isoleucine, proline, histidine, lysine, arginine, aspartic acid, tryptophan, It may contain at least one or more selected from the group consisting of glutamine and asparagine. Preferably, the amino acid may include a sulfur-containing amino acid, and may include at least one selected from the group consisting of methionine, taurine, L-cysteine, homocysteine, and cystine.

According to one embodiment of the present invention, the amino acid, 0.001% to 1% by weight of the polishing slurry composition; 0.01% to 0.8% by weight; 0.1% to 0.6% by weight; 0.1% to 0.5% by weight; Or it may be included in 0.1% by weight to 0.4% by weight. When included within the above range, excellent polishing performance of the polishing target film may be imparted, and erosion and dishing of the polishing target film may be improved.

According to one embodiment of the present invention, the amino acid may be applied to the polishing slurry composition by mixing a sulfur-containing amino acid and a non-sulfur-containing amino acid, for example, the mixing ratio of sulfur-containing amino acid to non-sulfur-containing amino acid in the amino acid ( w/w) may be 1:4 to 1:1. When the mixing ratio is within the range, excellent polishing performance of the polishing target film may be imparted and erosion and dishing of the polishing target film may be improved.

According to one embodiment of the present invention, the polishing slurry composition according to the present invention may further include a polishing accelerator, a polishing catalyst, or both. The polishing accelerator promotes a chemical reaction between the oxidizing agent and the polishing target film to enhance polishing of the polishing target film, and can improve polishing characteristics such as a polishing rate and reduce the occurrence of dishing. For example, it may contain metals, non-metals, or both. The polishing accelerator is silver (Ag), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), molybdenum (mo), manganese (mn), nionium (Nb), nickel ( Metals, ions and their It may include at least one selected from the group consisting of oxides of.

According to one embodiment of the present invention, the catalyst can transfer electrons from a metal to be oxidized to an oxidizing agent and increase a polishing rate, and is, for example, an iron-containing compound or an iron ion, and includes iron nitrate (II or III); iron sulfate (II or III); iron (II or III) halides including fluoride, chloride, bromide and iodide; organic ferric (II and III) compounds such as iron perchlorates, perchlorates, perbromates and periodates, and acetates, acetylacetonates, citrates, gluconates, oxalates, phthalates, and succinates; It may include at least one selected from the group consisting of. For example, it may include at least one selected from the group consisting of iron nitrate, iron sulfate, iron halide, iron perchlorate, iron acetate, iron acetylacetonate, iron gluconate, iron oxalate, iron phthalate, and iron succinate.

According to one embodiment of the present invention, the polishing accelerator and the catalyst, respectively, 0.001% to 1% by weight of the polishing slurry composition; 0.001% to 0.8% by weight; 0.01% to 0.5% by weight; Or it may be included in 0.01% by weight to 0.1% by weight. When it is within the above range, excellent polishing performance for the polishing target film may be imparted and surface defects after polishing may be minimized. A dishing and etching rate may increase due to an increase in a polishing rate due to an increase in the content of the polishing accelerator and the catalyst.

According to one embodiment of the present invention, the pH adjuster is for preventing corrosion of a polishing target film or corrosion of a polishing machine and implementing a pH range suitable for polishing performance, and includes an acidic material or a basic material, and the acidic material is , nitric acid, hydrochloric acid, phosphoric acid, sulfuric acid, hydrofluoric acid, hydrobromic acid, iodic acid, formic acid, malonic acid, maleic acid, oxalic acid, acetic acid, adipic acid, citric acid, adipic acid, acetic acid, propionic acid, fumaric acid, lactic acid, salicylic acid, pimelin acid, benzoic acid, succinic acid, phthalic acid, butyric acid, glutaric acid, glutamic acid, glycolic acid, lactic acid, aspartic acid, tartaric acid, and at least one selected from the group consisting of salts, wherein the basic material is ammonium methyl propanol (ammonium methyl propanol; AMP), tetramethyl ammonium hydroxide (TMAH), ammonium hydroxide, potassium hydroxide, sodium hydroxide, magnesium hydroxide, rubidium hydroxide, cesium hydroxide, sodium hydrogen carbonate, sodium carbonate, imidazole and each It may contain at least one selected from the group consisting of salts.

The pH of the metal polishing slurry composition according to the present invention is preferably adjusted to obtain dispersion stability and an appropriate polishing rate according to the abrasive particles, and the pH of the polishing slurry composition is 1 to 12, preferably 1 to 6 It may have an acidic pH range. It may be advantageous to form an acidic region to control the etching rate and reduce the occurrence of surface defects (eg, dishing and erosion).

According to one embodiment of the present invention, the polishing slurry composition may have a zeta potential of 1 mV to 100 mV, preferably 10 mV to 70 mV. When the absolute value of the zeta potential is high, the force to repel each other becomes strong, so that aggregation does not occur easily. Therefore, the polishing slurry composition of the present invention exhibits a high absolute value of zeta potential even in an acidic region, and as a result, it is possible to realize high dispersion stability and excellent polishing power.

According to one embodiment of the present invention, the polishing slurry composition may be applied to a polishing process of a semiconductor device and a display device.

According to an embodiment of the present invention, the polishing slurry composition has a polishing rate of 10 Å/min or more for a polishing target film in a polishing process (eg CMP); 100 Å/min or more; 500 Å/min or more; Preferably, it may be 500 Å/min to 4000 Å/min.

According to an embodiment of the present invention, the polishing slurry composition may be applied to polishing a semiconductor wafer including a metal bulk film, and may be applied, for example, to polishing a metal bulk layer and a barrier metal layer formed on a semiconductor wafer. . For example, it may be a semiconductor pattern wafer having an insulating layer on a substrate, a pattern layer having a barrier metal layer formed on the insulating layer, and a metal bulk layer formed on the pattern layer.

For example, the insulating layer may be a silicon or silicon oxide film. For example, the barrier metal layer may include a metal, a metal alloy, or an intermetallic compound, and may include, for example, indium (In) or tin (Sn). ), Silicon (Si), Titanium (Ti), Vanadium (V), Gadolium (Ga), Manganese (mn), Iron (Fe), Cobalt (Co), Copper (Cu), Zinc (Zn), Zirconium ( Zr), hafnium (Hf), aluminum (Al), niobium (Nb), nickel (Ni), chromium (Cr), molybdenum (mo), tantalum (Ta), ruthenium (Ru), tungsten (W), Titanium (Ti), Nickel (Ni), Chromium (Cr), Neodymium (Nd), Rubidium (Rb), Gold (Au), Platinum (pt), Gallium (Ga), Bismuth (Bi), Silver (Ag) And it may include at least one selected from the group consisting of palladium (pd).

For example, the pattern layer may be used for metal wiring such as metal wiring, contact plugs, via contacts, and trenches.

For example, the metal bulk layer (or metal layer) is indium (In), tin (Sn), silicon (Si), titanium (Ti), vanadium (V), gadollium (Ga), manganese (mn) , Iron (Fe), Cobalt (Co), Copper (Cu), Zinc (Zn), Zirconium (Zr), Hafnium (Hf), Aluminum (Al), Niobium (Nb), Nickel (Ni), Chromium (Cr) , Molybdenum (Mo), Tantalum (Ta), Ruthenium (Ru), Tungsten (W), Titanium (Ti), Nickel (Ni), Chromium (Cr), Neodymium (Nd), Rubidium (Rb), Gold (Au), at least one selected from the group consisting of vanadium (V) and platinum (pt).

Hereinafter, the present invention will be described in more detail by examples and comparative examples.

However, the following examples are only for illustrating the present invention, and the content of the present invention is not limited to the following examples.

Example

Examples 1 to 2 are colloidal silica having an average particle size of 20 nm to 120 nm according to the contents of Table 1, hydrogen peroxide, iron ions (iron (III) nitrate nonahydrate), sulfur-containing amino acids and A dishing improver (long chain polymer, molecular weight: 10K, PAM: Polyacrylamide) was added to prepare a polishing slurry composition of pH 2.1.

comparative example

Comparative Examples 1 to 8 are colloidal silica having an average particle size of 20 nm to 120 nm according to the contents of Table 1, hydrogen peroxide, iron ions (Iron (III) Nitrate nonahydrate), amino acids and dishing improvers (Long chain polymer, molecular weight: 10K, PAM: Polyacrylamide (polyacrylamide) was added to prepare a polishing slurry composition of pH 2.1.

In Comparative Examples 9 to 10, colloidal silica having an average particle size of 20 nm to 120 nm according to the contents of Table 1, hydrogen peroxide, iron ions (Iron (III) Nitrate nonahydrate) and amino acids were added to A polishing slurry composition of pH 2.1 was prepared.

abrasive grain oxidizer catalyst amino acid polymer pH Example 1 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% methionine
(methionine)
0.2wt% PAM 10K
0.1wt% 2.1 Example 2 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% cysteine
(cysteine)
0.2wt% PAM 10K
0.002wt% 2.1 Example 3 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% methionine
0.2wt% PAM 10K
0.002wt% 2.1 Comparative Example 1 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% methionine
0.05wt% PAM 10K
0.002wt% 2.1 Comparative Example 2 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% methionine
0.05wt% PAM 10K
0.1wt% 2.1 Comparative Example 3 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% methionine
0.5wt% PAM 10K
0.002wt% 2.1 Comparative Example 4 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% methionine
0.5wt% PAM 10K
0.1wt% 2.1 Comparative Example 5 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% nicotine
0.2wt%
(nicotinic acid) PAM 10K
0.002wt% 2.1 Comparative Example 6 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% glucosan
(gluconic acid)
0.2wt% PAM 10K
0.002wt% 2.1 Comparative Example 7 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.008wt% nicotinic acid
0.2wt% - 2.1 Comparative Example 8 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.008wt% gluconic acid
0.2wt% - 2.1 Comparative Example 9 colloidal silica
0.1wt% hydrogen peroxide
0.1wt% iron ion
0.012wt% - - 2.1

Measurement of Polishing Performance of Slurry Composition for Metal Polishing

In order to evaluate the polishing characteristics, the dishing, erosion and etching rate of the pattern surface after polishing and polishing of the Mo pattern wafer were measured using the polishing slurry compositions according to Examples and Comparative Examples, and the results are in Table 2 and Fig. 1.

The polishing rate for the Mo film quality was measured under the following polishing conditions.

[Polishing conditions]

1. Polishing equipment - KCT_ST-01

2. Platen speed - 100 rpm

3. Carrier speed - 103 rpm

4. Wafer pressure - 3.0 psi

6. Slurry flow rate - 250 ml/min

7. Pad - IC1000 pad

Mo removal rate
(Å/min) Mo etch rate
dishing
(Å) erosion
(Å) Example 1 886 11 5 740 Example 2 850 13 17 801 Example 3 786 13 11 756 Comparative Example 1 545 23 62 831 Comparative Example 2 599 25 53 816 Comparative Example 3 480 12 21 867 Comparative Example 4 512 11 24 842 Comparative Example 5 756 59 99 947 Comparative Example 6 888 101 204 1001 Comparative Example 7 1194 34 142 1049 Comparative Example 8 826 24 231 1031 Comparative Example 9 906 199 247 1024

From Table 2, it can be seen that when the polymer (PAM) having a molecular weight of 10K is added, the etch rate is controlled to lower the occurrence of erosion. It can be confirmed that Examples 1 and 2 of the present invention can provide improved effects in dishing and erosion at the same time as securing a high removal rate of Mo compared to Comparative Examples 1 to 9. In Example 3, the content of the polymer (pAM) is reduced compared to Example 1, so the polishing rate tends to be lowered. In Comparative Example 3 and Comparative Example 4, dishing and erosion tend to increase as the content of amino acid and polymer (pAM) increases. In Comparative Examples 5 to 6, dishing and erosion tend to increase when non-sulfur-containing amino acids are applied.

In the present invention, a polymer having a long chain (high molecular weight) and a sulfur-containing amino acid are applied to control the etching rate, and metal polishing has an effect of improving polishing performance for a metal film and defects (dicing and erosion) after polishing. A slurry composition can be provided.

As described above, although the embodiments have been described with limited drawings, those skilled in the art can apply various technical modifications and variations based on the above. For example, the described techniques may be performed in an order different from the method described, and/or components of the described system, structure, device, circuit, etc. may be combined or combined in a different form than the method described, or other components may be used. Or even if it is replaced or substituted by equivalents, appropriate results can be achieved. Therefore, other implementations, other embodiments, and equivalents of the claims are within the scope of the following claims.

Claims (19)

abrasive particles;
dishing improvers; and
oxidizer;
including,
The dishing improver,
The weight average molecular weight (m _W ) is 800 or more and is a carboxylic acid-containing polymer,
Polishing slurry composition.
According to claim 1,
The polymer includes a water-soluble polymer containing carboxylic acid, a copolymer thereof, or both,
The polymers are polyacrylic acid, poly Maleic acid, poly methacrylic acid, poly butadiene-co-maleic acid, poly acrylic acid/ Polyacrylamide-co-maleic acid, polyacrylamide, polyacrylamide-co-acylic acid, polycarboxylic acid, poly(acrylic acid-maleic acid) , poly(acrylonitrile-butadiene-acrylic acid), poly(acrylonitrile-butadiene-methacrylic acid), poly(acrylic acid-co-maleic acid), poly(methyl methacrylate-co-methacrylic acid) (poly( methyl methacrylate-co-methacrylic acid), poly(N-isopropylacrylamide-co-methacrylic acid), poly(N-isopropylacrylamide-co-methacrylic acid) -co-octadecyl acrylate) (poly(N-isopropylacrylamide-co-methacrylic acid-co-octadecyl acrylate)), poly(tert-butyl acrylate-co-ethylacrylic-co-methacrylic acid (poly(tert- butyl acrylate-co-ethyl acrylate-co-methacrylic acid, poly(methyl methacrylate), methyl methacrylate polymer-methyl methacrylate copolymer, poly (poly(methyl vinyl ether-alt-maleic acid)), poly(styrene-alt-maleic acid) sodium salt solution, poly(4 -Styrenesulfonic acid-co-maleic acid (poly(4-styrenesulfonic acid-co-maleic acid) sodium salt), poly(styrene-co-maleic acid), partial isobutyl ester (poly(styrene-co-maleic acid) ), partial isobutyl ester), poly[(isobutylene-alt-maleic acid, ammonium salt)-co-(isobutylene-alt-maleic anhydride)](poly[(isobutylene-alt-maleic acid, ammonium salt) -co-(isobutylene-alt-maleic anhydride)], poly(methyl vinyl ether-alt-maleic acid monoethyl ester) solution, polyacrylic acid/sulfonic acid copolymer Polymer, polysulfonic acid/acrylamide copolymer, polyacrylamidemethylpropanesulfonic acid, polyacrylic acid/styrene copolymer, polyacrylic acid, polymethacrylic acid, and polymaleic acid, and at least one repeating unit of polypropylene oxide methacrylic acid, polypropylene oxide a copolymer comprising at least one repeating unit selected from the group consisting of propylene oxide acrylic acid, polyethylene oxide methacrylic acid, and polyethylene oxide acrylic acid; To include at least one selected from the group consisting of,
Polishing slurry composition.
According to claim 1,
The dishing improver,
0.001% to 1% by weight of the polishing slurry composition,
Polishing slurry composition.
According to claim 1,
The abrasive particles may include metal oxides; and metal oxides coated with organic or inorganic materials; or both,
The metal oxide includes at least one selected from the group consisting of silica, ceria, zirconia, alumina, titania, barium, titania, germania, mangania, and magnesia,
Polishing slurry composition.
According to claim 1,
The abrasive particles,
Including self-assembly of microparticles, colloidal particles, or both,
The abrasive particles,
To include primary particles of 5 nm to 150 nm and secondary particles of 30 nm to 300 nm,
Polishing slurry composition.
According to claim 1,
The abrasive particles,
0.1% to 10% by weight of the polishing slurry composition,
Polishing slurry composition.
According to claim 1,
The oxidizing agent,
Hydrogen peroxide, urea Hydrogen peroxide, urea, percarbonate, periodic acid, periodate, perchloric acid, perchlorate, perbromic acid, perbromate, perboric acid, perborate, potassium permanganate, sodium perborate , Permanganic Acid, Permanganate, Persulfate, Bromate, Chlorite, Chlorate, Chromate, Dichromate, Chromium Compound, Iodate, Iodic Acid, Ammonium Peroxide Sulfate , Benzoyl Peroxide, Calcium Peroxide, Barium Peroxide, Sodium Peroxide, Dioxygenyl, Ozone, Ozonide, Nitrate, Hypochlorite, Hypochlorite ( At least one selected from the group consisting of hypohalite), chromium trioxide, pyridinium chlorochromate, nitrous oxide, monopersulfate salt, dipersulfate salt, and sodium peroxide which includes,
Polishing slurry composition.
According to claim 1,
The oxidizing agent,
0.0001% to 5% by weight of the polishing slurry composition,
Polishing slurry composition.
According to claim 1,
amino acid; Including more,
Polishing slurry composition.
According to claim 9,
The amino acid is
At least one selected from the group consisting of lysine, methionine, cysteine, tyrosine, glycine, alanine, serine, phenylalanine, threonine, valine, leucine, isoleucine, proline, histidine, lysine, arginine, aspartic acid, tryptophan, glutamine and asparagine will,
Polishing slurry composition.
According to claim 9,
The mixing ratio (w/w) of sulfur-containing amino acids to non-sulfur-containing amino acids in the above amino acids is
1: 4 to 1: 1,
Polishing slurry composition.
According to claim 9,
The amino acid is
0.001% to 1% by weight of the polishing slurry composition,
Polishing slurry composition.
According to claim 1,
iron-containing catalysts;
Including more,
Polishing slurry composition.
According to claim 13,
The iron-containing catalyst,
iron-containing compounds, or iron ions; iron nitrate (II or III); iron sulfate (II or III); iron (II or III) halides including fluoride, chloride, bromide and iodide; organic ferric (II and III) compounds such as iron perchlorates, perchlorates, perbromates and periodates, and acetates, acetylacetonates, citrates, gluconates, oxalates, phthalates, and succinates; To include at least one selected from the group consisting of,
Polishing slurry composition.
According to claim 13,
The iron-containing catalyst,
0.0001% to 1% by weight of the polishing slurry composition,
Polishing slurry composition.
According to claim 1,
The pH of the polishing slurry composition is
Having a range of 1 to 12,
Polishing slurry composition.
According to claim 1,
In the polishing slurry composition, the film to be polished is a metal film,
The metal film includes at least one selected from the group consisting of a metal, a metal nitride, a metal oxide, and a metal alloy.
Polishing slurry composition.
According to claim 17,
The metal, metal nitride, metal oxide, and metal alloy are, respectively, indium (In), tin (Sn), silicon (Si), titanium (Ti), vanadium (V), gadollium (Gd), gallium (Ga) , manganese (mn), iron (Fe), cobalt (Co), copper (Cu), zinc (Zn), zirconium (Zr), hafnium (Hf), aluminum (Al), niobium (Nb), nickel (Ni) , chromium (Cr), molybdenum (mo), tantalum (Ta), ruthenium (Ru) and tungsten (W) containing at least one selected from the group consisting of,
Polishing slurry composition.
According to claim 1,
The polishing rate of the polishing slurry composition for the film to be polished is
500 Å / min or more,
Polishing slurry composition.

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