Abrasive Slurry Composition

Abstract

The present invention relates to a polishing slurry composition, and more particularly to a polishing slurry composition for polishing polycrystalline silicon, comprising colloidal silica abrasive particles, a quaternary ammonium cationic monomer, and an acidic substance.

Description

[Technical Field]

[0001] The present invention relates to a polishing slurry composition for a chemical mechanical polishing (CMP) process for a polycrystalline silicon film. [Background technology]

[0002] Chemical mechanical polishing (CMP) is a process in which the surface of a semiconductor wafer is polished flat using a slurry containing abrasives and various compounds while rotating the surface of the wafer against a polishing pad. Generally, the metal polishing process involves the use of an oxidizing agent to polish the surface of a semiconductor wafer. x It is known that this occurs through repeated processes of the formation of metal oxides and the removal of the formed metal oxides by abrasive particles.

[0003] As semiconductor devices become more diverse and highly integrated, fine patterning techniques are being used, resulting in increasingly complex surface structures and larger surface film steps. In semiconductor device fabrication, chemical mechanical polishing (CMP) is used as a planarization technique to remove steps in specific films formed on wafers. CMP compositions are selective for removing certain types of integrated circuit components relative to other components. Compositions and methods for CMP of wafer surfaces are widely known in the relevant technical field. CMP slurry compositions for polishing semiconductor wafer surfaces typically contain abrasive particles and various additive compounds. Flash memory devices with three-dimensional transistor stacks (3D flash memory) are becoming increasingly popular. Polishing slurries for 3D flash applications generally must provide not only a high polycrystalline silicon removal rate and silicon oxide removal selectivity, but also good surface photography and low defect levels. Furthermore, they must overcome the limitations of polishing slurry compositions that can only be achieved in alkaline regions to ensure high-quality polycrystalline silicon removal rates. Summary of the Invention [Problem to be solved by the invention]

[0004] In order to solve the above-mentioned problems, the present invention relates to a polishing slurry composition for polishing polycrystalline silicon films that can achieve high polishing performance for polycrystalline silicon, for example, high polishing performance in an acidic range.

[0005] However, the problems that the present invention aims to solve are not limited to those mentioned above, and further problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0006] One embodiment of the present invention relates to a polishing slurry composition for polishing polycrystalline silicon, comprising colloidal silica abrasive particles, a quaternary ammonium cationic monomer, and an acidic substance.

[0007] According to one embodiment of the present invention, the colloidal silica abrasive particles have a cationic surface charge, and the colloidal silica abrasive particles may be particles of a single size between 10 nm and 200 nm, or may include mixed particles having two or more different sizes between 10 nm and 200 nm.

[0008] According to an embodiment of the present invention, the abrasive particles may be present in an amount of 0.0001% to 10% by weight of the slurry composition.

[0009] According to one embodiment of the present invention, the quaternary ammonium cationic monomer may include at least one of compounds represented by the following Formulas 1 to 3.

[0010] [ka]

[0011] [ka]

[0012] (In the above-mentioned Chemical Formula 1, R 1 ~R 4 are each selected from a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, and a linear or branched alkoxy group having 1 to 50 carbon atoms;

[0013] In the above formula 2, R 1 ~R 4 are each selected from hydrogen, a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, a linear or branched alkoxyl group having 1 to 50 carbon atoms, and an aromatic ring having 6 to 30 carbon atoms;

[0014] In the formulas 1 and 2, X is a counter ion, and is hydroxide (OH - ), halogens, sulfates (SO4 2- ), phosphate (PO4 3- ), nitrate (NO3 - ), hydrogen sulfate (HSO4 - ), methyl methanesulfonate (CH3SO3 - ), perchlorate (ClO4 - ), and hexafluorophosphate (PF6 - ) are selected from

[0015] [ka]

[0016] (In the above Chemical Formula 3, R, R 8 and R 9 is selected from hydrogen, a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, a linear or branched alkoxyl group having 1 to 50 carbon atoms, and an aromatic ring having 6 to 30 carbon atoms;

[0017] R 1 is a linear or branched alkylene group having 1 to 50 carbon atoms, and [ka] (R 5 and R 7 are each a linear or branched alkylene group having 1 to 50 carbon atoms, and R 6 is selected from hydrogen, a linear or branched alkyl group having 1 to 50 carbon atoms, or a linear or branched alkenyl group having 2 to 50 carbon atoms, and n is 0 or 1;

[0018] R 2 ~R 4 are each selected from hydrogen, a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, and an aromatic ring having 6 to 30 carbon atoms;

[0019] X is the counterion, hydroxide (OH - ), halogens, sulfates (SO4 2- ), phosphate (PO4 3- ), nitrate (NO3 - ), hydrogen sulfate (HSO4 - ) or methyl methanesulfonate (CH3SO3 - ), perchlorate (ClO4 - ) and hexafluorophosphate (PF6 - ) are selected from

[0020] According to one embodiment of the present invention, in Formula 1, R 1 ~R 4 can each be selected from linear or branched alkyl groups having 1 to 10 carbon atoms.

[0021] According to one embodiment of the present invention, in Formula 2, R 2 ~R 4 are each selected from linear or branched alkyl groups having 1 to 10 carbon atoms, and in the above chemical formula 2, R 8 ~R 9 At least one of them may be hydrogen.

[0022] According to one embodiment of the present invention, the quaternary ammonium cationic monomer may be present in an amount of 0.0001% to 0.5% by weight of the composition.

[0023] According to one embodiment of the present invention, the acidic substance may include an inorganic acid, an organic acid, or both of them, and the acidic substance may be present in an amount of 0.0001 wt % to 1 wt % of the polishing slurry composition.

[0024] According to one embodiment of the present invention, the inorganic acid may include at least one selected from the group consisting of sulfuric acid, nitric acid, phosphoric acid, silicic acid, hydrofluoric acid, boric acid, bromic acid, iodic acid, hydrochloric acid, and perchloric acid.

[0025] According to one embodiment of the present invention, the organic acid comprises a monocarboxylic acid, a dicarboxylic acid, or a combination of both thereof, and the organic acid may be citric acid, oxalic acid, propionic acid, stearic acid, pyruvic acid, acetic acid, acetoacetic acid, glyoxylic acid, malic acid, malonic acid, dimethylmalonic acid, maleic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, phthalic acid, trimellitic acid, tartaric acid, glycolic acid, 2,2-dimethylglutaric acid, or lactic acid. The composition may contain at least one selected from the group consisting of ethanol, ethanolamine, ethanolamine, ethanolamine-containing alcohol, ethanolamine-containing ethanol ...

[0026] According to one embodiment of the present invention, when two or more kinds of acidic substances are used, the mass ratio of the first acidic substance to the remaining acidic substances may be 9:1 to 1:9.

[0027] According to one embodiment of the present invention, the polishing slurry composition further comprises a basic compound, and the basic compound is ammonia, ammonium methyl propanol (AMP), tetramethyl ammonium hydroxide (TMAH), ammonium hydroxide, potassium hydroxide, sodium hydroxide, magnesium hydroxide, rubidium hydroxide, cesium hydroxide, sodium bicarbonate, sodium carbonate, imidazole, monoethanolamine (MEA), diethanolamine (Diethanolamine), amine, DEA), triethanolamine (TEA), 1,5-diamino-3-pentanol, 2-dimethylamino-2-methyl-1-propanol, 1-amino-2-propanol, 1-dimethylamino-2-propanol, 1,3-diamino-2-propanol, 3-dimethylamino-1-propanol, 2-amino-1-propanol, 2-dimethylamino-1-propanol, 2-diethylamino-1-propanol, 2-(2-aminoethylamino)ethanol, 2-diethylamino-1-ethanol, 2-ethylamino-1-ethanol, 1-(dimethylamino)2-propanol, N-methyldiethanolamine, N-propyldiethanolamine, N-isopropyldiethanolamine, N-(2-methylpropyl)diethanolamine Nn-butyldiethanolamine, Nt-butylethanolamine, N-cyclohexyldiethanolamine, 2-(dimethylamino)ethanol, 2-diethylaminoethanol, 2-dipropylaminoethanol, 2-butylaminoethanol, 2-t-butylaminoethanol, 2-cycloaminoethanol, 2-amino-2-pentanol, 2-[bis(2-hydroxyethyl)amino]-2-methyl-1-propanol, 2-[bis(2-hydroxyethyl)amino]-2-propanol, N,N-bis(2-hydroxypropyl)ethanolamine, 2-amino-2-methyl-1-propanol, tris(hydroxymethyl)aminomethane, triisopropanolamine, tetraethylammonium hydroxideThe compound may include at least one or more selected from the group consisting of tetrapropylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), methyl(trishydroxyethyl)ammonium hydroxide, tributylethylammonium hydroxide, (2-hydroxyethyl)triethylammonium hydroxide, (2-hydroxyethyl)tripropylammonium hydroxide, and (1-hydroxypropyl)trimethylammonium hydroxide.

[0028] According to one embodiment of the present invention, the pH of the slurry composition may be 2-11.

[0029] According to an embodiment of the present invention, the polishing rate of the polishing slurry composition for a polycrystalline silicon film may be 2000 Å / min or more.

[0030] According to one embodiment of the present invention, the polishing slurry composition has a pH of 3 to 5 or a pH of 9 to 11, and the selectivity of the polycrystalline silicon film to the silicon nitride film, the silicon oxide film, or a film containing both of them may be 10:1 to 1000:1. [Effects of the Invention]

[0031] The present invention provides a polishing slurry composition that can ensure a high polishing rate for polycrystalline silicon films and improve polishing performance. For example, it can ensure a high polishing rate for polycrystalline silicon films not only in the basic region but also in the acidic region, and can realize a good polishing selectivity for other films such as nitride films and oxide films. DETAILED DESCRIPTION OF THE INVENTION

[0032] The present invention will be described in detail below with reference to the embodiments. However, various modifications may be made to the embodiments, and the scope of the patent application is not limited or restricted by such embodiments. All modifications, equivalents, or alternatives to the embodiments should be understood as being included in the scope of the patent.

[0033] The terms used in the embodiments are used merely for the purpose of explanation and are not to be construed as limiting. A singular expression includes a plural expression unless the context clearly indicates otherwise. In this specification, the terms "comprise" or "have" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and should be understood as not precluding the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0034] Unless otherwise defined, 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 present invention pertains. Commonly used predefined terms should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted as having an ideal or overly formal meaning unless expressly defined herein.

[0035] In the description of the present embodiment, if it is determined that a detailed description of related known technology unnecessarily obscures the gist of the embodiment, the detailed description will be omitted.

[0036] Furthermore, when describing components of an embodiment, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are used to distinguish the component from other components, and do not limit the nature, order, or sequence of the components. When a component is described as being "coupled," "coupled," or "connected" to another component, it should be understood that the component may be directly coupled or connected to the other component, but that additional components may be "coupled," "coupled," or "connected" between each component.

[0037] Components having functions common to those included in any of the embodiments will be described using the same names in other embodiments. Unless otherwise specified, the description of one embodiment will be applied to the other embodiments, and detailed description will be omitted to the extent that they overlap.

[0038] Hereinafter, embodiments of the present invention will be described in detail. In the description of the present invention, if a detailed description of related known functions or configurations is deemed to unnecessarily obscure the gist of the present invention, such detailed description will be omitted. Furthermore, the terms used in this specification are used to appropriately express preferred embodiments of the present invention, and may vary depending on the intentions of users or operators, or the practices in the field to which the present invention belongs. Therefore, the definitions of these terms should be based on the overall content of this specification.

[0039] Throughout the specification, when an element is referred to as being "on" another element, this includes not only when the element is in contact with the other element, but also when there is an additional element between the two elements.

[0040] Throughout the specification, when any part "comprises" any component, this does not mean that it excludes other components, but that it may further include other components.

[0041] The present invention will be described in detail below with reference to examples of the polishing slurry composition, but the present invention is not limited to these examples.

[0042] The present invention relates to a polishing slurry composition, and according to one embodiment of the present invention, the polishing slurry composition includes colloidal silica abrasive particles; a quaternary ammonium cationic monomer; and an acidic substance.

[0043] According to one embodiment of the present invention, the colloidal silica abrasive particles include particles with a size of 10 nm to 200 nm or 20 nm to 200 nm. By including the abrasive particles within this size range, it is possible to ensure a desired polishing rate and prevent over-polishing due to size increase. For example, the abrasive particles may be single-sized particles of 10 nm to 200 nm, or may contain mixed particles having two or more different sizes of 10 nm to 200 nm. For example, the abrasive particles may include first particles of 10 nm to 50 nm and second particles of over 50 nm to 100 nm, with the mixing ratio (mass ratio) of the first particles to the second particles being 1:0.1 to 10. The size may refer to diameter, length, thickness, etc., depending on the particle shape. For example, the abrasive particle size may refer to diameter, radius, maximum length, etc., depending on the particle shape. The average particle size of the abrasive particles refers to the average value of multiple particle diameters within a field of view that can be measured by XRD, SEM, TEM, BET, or dynamic light scattering. For example, the first particles may be non-aggregated particles initially formed in a synthesis reaction, and a plurality of the first particles may aggregate to form second particles. If the size of the first particles is less than the above range, the polishing rate may decrease, and if it exceeds the above range, uniformity may decrease. Also, if the size of the second particles is less than the above range, the polishing rate may decrease or small particles may be generated by milling, which may decrease cleanability and cause excessive defects on the wafer surface. If it exceeds the above range, excessive polishing may occur, which may cause dishing, erosion, and surface defects.

[0044] In one embodiment of the present invention, the colloidal silica abrasive particles are 30 (m 2 / g)~150(m 2 / g) or 30 (m 2 / g)~150(m 2 For example, the abrasive particles may contain mixed particles having two or more different specific surface areas of 30 (m / g). 2 / g)~80(m 2 / g) specific surface area of ​​the first particles and 80 (m 2 / g) Excess~150(m)2 The polishing agent may include second particles having a specific surface area of ​​1 / g, and the mixing ratio (mass ratio) of the first particles to the second particles may be 1:0.1 to 10. If the specific surface area falls within this range, a sufficient area of ​​contact with the polishing target film can be secured, providing a high level of polishing rate and reducing the occurrence of scratches and dishing on the surface of the polishing target film. The specific surface area can be measured by the Brunauer-Emmett-Teller (BET) method. For example, it may be measured by the BET 6-point method using a porosimetry analyzer (Belsorp-II mini, Bell Japan Inc.) and nitrogen gas adsorption / flow method.

[0045] In one embodiment of the present invention, the colloidal silica abrasive particles may have at least one shape selected from the group consisting of spherical, angular, acicular, and plate-like shapes.

[0046] In one embodiment of the present invention, the colloidal silica abrasive particles may exhibit a cationic surface charge due to organic and / or inorganic coating, surface substitution, or a combination of both. In addition, the colloidal silica abrasive particles may exhibit a cationic surface charge due to the type of substituent on the silica particle surface, e.g., NH3 + The silica surface charge can be controlled by controlling the density (or number) of the substituents, such as cations, etc. For example, the cationic surface charge of the colloidal silica abrasive particles exhibits a positive charge zeta potential of 8 mV or more, 10 mV or more, 15 mV or more, or 40 mV or more in a liquid carrier at a pH of 1 to 6.

[0047] In one embodiment of the present invention, the colloidal silica abrasive particles may be included in the slurry composition in an amount of 0.0001 wt % to 10 wt %, 0.001 wt % to 10 wt %, or 0.1 wt % to 10 wt %. When included within this range, a desired polishing rate can be achieved and / or the polishing rate can be adjusted to achieve a desired selectivity depending on the film to be polished (e.g., a polycrystalline silicon film), and the number of abrasive particles remaining on the surface of the film to be polished (e.g., a polycrystalline silicon film) due to an increased abrasive particle content can be reduced, thereby preventing a decrease in the polishing rate due to a low content and secondary defects such as dishing or erosion in the polished pattern.

[0048] According to one embodiment of the present invention, the quaternary ammonium cationic monomer may include at least one of compounds represented by the following Formula 1, Formula 2, and Formula 3. For example, the quaternary ammonium cationic monomer has a hydrophobic group and a hydrophilic group due to an aliphatic hydrocarbon chain (C-Chain), and can achieve a high polishing rate when polishing polycrystalline silicon.

[0049] [ka]

[0050] In one embodiment of the present invention, in Formula 1, R 1 , R 2 , R 3 and R 4 may each be selected from a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, and a linear or branched alkoxyl group having 1 to 50 carbon atoms.

[0051] In one embodiment of the present invention, in Formula 1, X is a counter ion, such as hydroxide (OH - ), halogens, sulfates (SO4 2- ), phosphate (PO4 3- ), nitrate (NO3 - ), hydrogen sulfate (HSO4 -), methyl methanesulfonate (CH3SO3 - ), perchlorate (ClO4 - ), and hexafluorophosphate (PF6 - The alkoxyl group is represented by -O-R', and R' may be selected from a linear or branched alkyl group having 1 to 50 carbon atoms and a linear or branched alkenyl group having 2 to 50 carbon atoms.

[0052] As an example of the present invention, in the above Chemical Formula 1, the "number of carbon atoms" of the alkyl may be selected from 1 to 50; 1 to 30; 1 to 20; 1 to 10; or 1 to 3.

[0053] As an example of the present invention, in the above Chemical Formula 2, the "number of carbon atoms" of alkenyl may be selected from 2 to 50; 2 to 30; 2 to 20; 2 to 10; or 2 to 3.

[0054] [ka]

[0055] In one embodiment of the present invention, in Formula 2, R 1 , R 2 , R 3 and R 4 are each selected from hydrogen, a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, a linear or branched alkoxyl group having 1 to 50 carbon atoms, and an aromatic ring having 6 to 30 carbon atoms, and the alkoxyl group is represented by -O-R', where R' may be selected from a linear or branched alkyl group having 1 to 50 carbon atoms and a linear or branched alkenyl group having 2 to 50 carbon atoms.

[0056] Preferably, in the above formula 2, R 1 , R 2 , R 3 and R 4 are each selected from hydrogen, a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, and an aromatic ring having 6 to 30 carbon atoms; R 1 , R2 , R 3 and R 4 Not all of it is hydrogen.

[0057] In one embodiment of the present invention, in the formula 2, X is a counter ion, and may be hydroxide (OH - ), halogens, sulfates (SO4 2- ), phosphate (PO4 3- ), nitrate (NO3 - ), hydrogen sulfate (HSO4 - ) or methyl methanesulfonate (CH3SO3 - ), perchlorate (ClO4 - ), and hexafluorophosphate (PF6 - ) may be selected from

[0058] As an example of the present invention, in the above Chemical Formula 2, the "number of carbon atoms" of the alkyl may be selected from 1 to 50; 1 to 30; 1 to 20; 1 to 10; or 1 to 3.

[0059] As an example of the present invention, in the above Chemical Formula 2, the "number of carbon atoms" of alkenyl may be selected from 2 to 50; 2 to 30; 2 to 20; 2 to 10; or 2 to 3.

[0060] [ka]

[0061] In one embodiment of the present invention, in Formula 3, R, R 8 and R 9 are each selected from hydrogen, a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, a linear or branched alkoxyl group having 1 to 50 carbon atoms, and an aromatic ring having 6 to 30 carbon atoms, and the alkoxyl group is represented by -O-R', and R' may be selected from a linear or branched alkyl group having 1 to 50 carbon atoms and a linear or branched alkenyl group having 2 to 50 carbon atoms. Preferably, in the above Chemical Formula 2, R and R 8 and R 9may each be selected from a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, and a linear or branched alkoxyl group having 1 to 50 carbon atoms.

[0062] In one embodiment of the present invention, in Formula 3, R 1 is a linear or branched alkylene group having 1 to 50 carbon atoms, and [ka] (R 5 and R 7 are each a linear or branched alkylene group having 1 to 50 carbon atoms, and R 6 may be selected from hydrogen, a straight-chain or branched alkyl group having 1 to 50 carbon atoms; or a straight-chain or branched alkenyl group having 2 to 50 carbon atoms; and n is 0 or 1).

[0063] In one embodiment of the present invention, in Formula 3, R 2 ~R 4 may each be selected from hydrogen, a linear or branched alkyl group having 1 to 50 carbon atoms, a linear or branched alkenyl group having 2 to 50 carbon atoms, and an aromatic ring having 6 to 30 carbon atoms.

[0064] In one embodiment of the present invention, in the formula 3, X is a counter ion, such as hydroxide (OH - ), halogens, sulfates (SO4 2- ), phosphate (PO4 3- ), nitrate (NO3 - ), hydrogen sulfate (HSO4 - ), or methyl methanesulfonate (CH3SO3 - ), perchlorate (ClO4 - ), and hexafluorophosphate (PF6 - ) may be selected from

[0065] In one example of the present invention, in the above Chemical Formula 3, the "number of carbon atoms" of the alkyl may be selected from 1 to 50; 1 to 30; 1 to 20; 1 to 10; or 1 to 3. Preferably, in the above Chemical Formula 2, R 8and R 9 At least one of them may be hydrogen.

[0066] As an example of the present invention, in the above Chemical Formula 3, the "number of carbon atoms" of alkenyl may be selected from 2 to 50; 2 to 30; 2 to 20; 2 to 10; or 2 to 3.

[0067] In one embodiment of the present invention, the quaternary ammonium cationic monomer may be dimethyldimethylammonium chloride, dimethyldiethylammonium chloride, dimethyldipropylammonium chloride, dimethyldioctylammonium chloride, dimethyldialkylammonium chloride, diethyldialkylammonium chloride, distearyldimethylammonium chloride, diallyldimethylammonium chloride (DADMAC), diallyldiethylammonium chloride, trimethyloctylammonium chloride, 2-trialkylammonioethyl methacrylate (e.g., 2-trimethylammonioethyl methacrylate chloride), The compound may contain at least one selected from the group consisting of 2-(trialkylamino)ethyl acrylate (e.g., 2-(trimethylamino)ethyl acrylate, methyl chloride quaternary salt), and 2-(trialkylamino)ethyl acrylate (e.g., 2-(trimethylamino)ethyl acrylate, methyl chloride quaternary salt).

[0068] In one example of the present invention, the quaternary ammonium cationic monomer is 0.0001 wt % to 0.5 wt % of the polishing slurry composition. When the quaternary ammonium cationic monomer is within this range, a high polishing rate can be achieved when polishing a polycrystalline silicon film, for example, a high polishing rate can be achieved for a polycrystalline silicon film in an acidic range.

[0069] According to one embodiment of the present invention, the acidic material functions as a pH adjuster for the polishing slurry composition, improves the dispersion stability of colloidal silica particles, and improves the polishing performance of polycrystalline silicon, and may include, for example, an inorganic acid, an organic acid, or both.

[0070] In one example of the present invention, the inorganic acid may include at least one selected from the group consisting of sulfuric acid, nitric acid, phosphoric acid, silicic acid, hydrofluoric acid, boric acid, bromic acid, iodic acid, hydrochloric acid, and perchloric acid.

[0071] In one embodiment of the present invention, the organic acid includes a monocarboxylic acid, a dicarboxylic acid, or both thereof, and examples of the organic acid include citric acid, oxalic acid, propionic acid, stearic acid, pyruvic acid, acetic acid, acetoacetic acid, glyoxylic acid, malic acid, malonic acid, dimethylmalonic acid, maleic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, phthalic acid, trimellitic acid, tartaric acid, glycolic acid, 2,2-dimethylglutaric acid, and lactic acid. The hydroxybenzoate may contain at least one selected from the group consisting of hydroxybenzoates, ...

[0072] In one embodiment of the present invention, the acidic material is present in the polishing slurry composition in an amount of 0.0001 wt % to 3 wt %, 0.001 wt % to 1 wt %, or 0.01 wt % to 1 wt %. If the amount is within this range, it is advantageous to obtain an effect of increasing the CMP polishing rate of polycrystalline silicon due to the increased content of the acidic material. When two or more types of acidic materials are used, the mass ratio of the first acidic material to the remaining acidic materials is 9:1 to 1:9, which can improve the polishing selectivity of polycrystalline silicon.

[0073] According to one embodiment of the present invention, the polishing slurry composition may further include a basic compound. In one embodiment of the present invention, the basic compound functions as a pH adjuster and improves the dispersion stability of colloidal silica particles and the polishing performance of polycrystalline silicon. The basic compound may be ammonia, ammonium methyl propanol (AMP), tetramethyl ammonium hydroxide (TMAH), ammonium hydroxide, potassium hydroxide, sodium hydroxide, magnesium hydroxide, rubidium hydroxide, cesium hydroxide, sodium bicarbonate, sodium carbonate, imidazole, monoethanolamine (MEA), diethanolamine (DIA), or the like.amine, DEA), triethanolamine (TEA), 1,5-diamino-3-pentanol, 2-dimethylamino-2-methyl-1-propanol, 1-amino-2-propanol, 1-dimethylamino-2-propanol, 1,3-diamino-2-propanol, 3-dimethylamino-1-propanol, 2-amino-1-propanol, 2-dimethylamino-1-propanol, 2-diethylamino-1-propanol, 2-(2-aminoethylamino)ethanol, 2-diethylamino-1-ethanol, 2-ethylamino-1-ethanol, 1-(dimethylamino)2-propanol, N-methyldiethanolamine, N-propyldiethanolamine, N-isopropyldiethanolamine, N-(2-methylpropyl)diethanolamine Nn-butyldiethanolamine, Nt-butylethanolamine, N-cyclohexyldiethanolamine, 2-(dimethylamino)ethanol, 2-diethylaminoethanol, 2-dipropylaminoethanol, 2-butylaminoethanol, 2-t-butylaminoethanol, 2-cycloaminoethanol, 2-amino-2-pentanol, 2-[bis(2-hydroxyethyl)amino]-2-methyl-1-propanol, 2-[bis(2-hydroxyethyl)amino]-2-propanol, N,N-bis(2-hydroxypropyl)ethanolamine, 2-amino-2-methyl-1-propanol, tris(hydroxymethyl)aminomethane, triisopropanolamine, tetraethylammonium hydroxide ammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide, tetrapentylammonium hydroxide (TBAH), methyl(trishydroxyethyl)ammonium hydroxide, tributylethylammonium hydroxideThe compound may contain at least one selected from the group consisting of (2-hydroxyethyl)triethylammonium hydroxide, (2-hydroxyethyl)triethylammonium hydroxide, (2-hydroxyethyl)tripropylammonium hydroxide, and (1-hydroxypropyl)trimethylammonium hydroxide.

[0074] In one example of the present invention, the basic compound is 0.0001 wt % to 3 wt %, 0.001 wt % to 1 wt %, or 0.01 wt % to 1.0 wt % of the polishing slurry composition, and if it is within the above range, it is advantageous to obtain the effect of increasing the CMP polishing amount of polycrystalline silicon.

[0075] According to one embodiment of the present invention, the polishing slurry composition has a pH of 2 to 11, and may be, for example, pH 3 to 5 or pH 9 to 11. The polishing slurry composition can achieve dispersion stability and high polishing performance for polycrystalline silicon films in the acidic range of pH 3 to 5. Furthermore, if the pH is outside this range and forms a highly basic range, significant shedding of semiconductor material may occur after polishing, and the surface roughness of the substrate to be polished, e.g., a wafer, may become uneven, resulting in defects such as dishing, erosion, corrosion, and surface unevenness.

[0076] According to one embodiment of the present invention, the polishing slurry composition is applied to polishing a substrate including a polycrystalline silicon layer, for example, it can be applied to a chemical-mechanical polishing (CMP) process of a substrate including a polycrystalline silicon layer.

[0077] According to one embodiment of the present invention, the polishing slurry composition has a positive zeta potential, for example, 1 mV to 100 mV, 10 mV to 80 mV, or 20 mV to 60 mV. If the zeta potential is within the above range, the polishing rate of the hydrophobic polycrystalline silicon film can be improved.

[0078] According to one embodiment of the present invention, the polishing slurry composition exhibits a negative zeta potential in the alkaline region, which may be -1 mV or less; -10 mV or less; -30 mV or less; or -30 mV to -100 mV.

[0079] According to one embodiment of the present invention, when a polishing process is performed on a substrate including the polycrystalline silicon film using the polishing slurry composition, the polishing rate for the polycrystalline silicon film may be 2000 Å / min or more; 3000 Å / min or more, for example, 2000 Å / min to 5000 Å / min.

[0080] According to one embodiment of the present invention, when a polishing process is performed on a substrate including a polycrystalline silicon film, a silicon nitride film, a silicon oxide film, or a film including two thereof using the polishing slurry composition, a high polishing selectivity of the polycrystalline silicon film can be achieved. For example, the selectivity of the polycrystalline silicon film to a silicon nitride film, a silicon oxide film, or a film including two thereof at a pH of 3 to 5 or a pH of 9 to 11 of the polishing slurry composition may be 10:1 to 3000:1.

[0081] The present invention will be described in more detail below with reference to examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0082] Example 1

[0083] According to Table 1 below, colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, a quaternary ammonium cationic monomer (diallyldimethylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0084] Example 2

[0085] According to Table 1 below, colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, a quaternary ammonium cationic monomer (diallyldimethylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0086] Example 3

[0087] According to Table 1 below, colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, a quaternary ammonium cationic monomer (diallyldimethylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0088] Example 4

[0089] According to Table 1 below, colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, a quaternary ammonium cationic monomer (diallyldimethylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0090] Example 5

[0091] According to Table 1 below, colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, a quaternary ammonium cationic monomer (diallyldimethylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0092] Example 6

[0093] According to Table 1 below, colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, a quaternary ammonium cationic monomer (diallyldimethylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0094] Example 7

[0095] According to Table 1 below, colloidal silica (30 nm to 40 nm in size) having a cationic surface charge, a quaternary ammonium cationic monomer (diallyldimethylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0096] Example 8

[0097] According to Table 1 below, colloidal silica (10 nm to 20 nm in size) having a cationic surface charge, a quaternary ammonium cationic monomer (diallyldimethylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0098] Example 9

[0099] According to Table 1 below, colloidal silica (size: 10 nm to 20 nm) having a cationic surface charge, a quaternary ammonium cationic monomer (diallyldimethylammonium chloride), and potassium hydroxide (KOH) as a pH adjuster were mixed until the pH reached 11, to prepare a polishing slurry composition.

[0100] Example 10

[0101] According to Table 1 below, colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, a quaternary ammonium cationic monomer (trimethyloctylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0102] Example 11

[0103] According to Table 1 below, colloidal silica having a cationic surface charge (size: 60 nm to 80 nm, F-2 or G-1), a quaternary ammonium cationic monomer (trimethyloctylammonium chloride), and nitric acid as a pH adjuster were mixed until the pH reached 4, to prepare a polishing slurry composition.

[0104] Comparative Example 1

[0105] According to Table 1, a polishing slurry composition was prepared in the same manner as in Example 1, except that a nitrogen-based nonionic compound (acrylamide) was added.

[0106] Comparative Example 2

[0107] According to Table 1, a polishing slurry composition was prepared in the same manner as in Example 1, except that the quaternary ammonium cationic monomer was not added.

[0108] Comparative Example 3

[0109] According to Table 1 below, a polishing slurry composition was prepared by mixing colloidal silica (60 nm to 80 nm in size) having a cationic surface charge, a cationic polymer (P2VP, Poly(2-vinylpyridine), and nitric acid as a pH adjuster until the pH reached 4.

[0110] Comparative Example 4

[0111] According to Table 1 below, a polishing slurry composition was prepared by mixing colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, a cationic polymer (PEI, Polyethyleneimine), and nitric acid as a pH adjuster until the pH reached 4.

[0112] Comparative Example 5

[0113] According to Table 1 below, a polishing slurry composition was prepared by mixing colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, an anionic polymer (PAA, Polyacrylic acid), and nitric acid as a pH adjuster until the pH reached 4.

[0114] Comparative Example 6

[0115] According to Table 1 below, a polishing slurry composition was prepared by mixing colloidal silica (size: 60 nm to 80 nm) having a cationic surface charge, a nonionic polymer (PEG, polyethylene glycol), and nitric acid as a pH adjuster until the pH reached 4.

[0116] Comparative Example 7

[0117] According to Table 1 below, a polishing slurry composition was prepared by mixing colloidal silica (30 nm to 40 nm in size) having a cationic surface charge, a nonionic polymer (PEG, polyethylene glycol), and nitric acid as a pH adjuster until the pH reached 4.

[0118] Evaluation of polishing characteristics

[0119] Using the polishing slurry compositions of the Examples and Comparative Examples, a substrate containing a polysilicon film was polished under the following polishing conditions.

[0120] [Polishing conditions]

[0121] (1) Polishing equipment: ST#01 (KCT)

[0122] (2)Carrier rpm / Platen rpm:87 / 93

[0123] (3) Wafer Pressure: 3 psi

[0124] (4)Surry Flow rate(ml / min):250ml / min

[0125] (5) Pad: IC1000

[0126] (6) Time: 60 seconds

[0127] (7) R-ring pressure: 6 psi

[0128] To evaluate the polishing characteristics, the polishing rate after polishing a polysilicon wafer substrate using the polishing slurry compositions of Examples and Comparative Examples and the recess on the pattern surface after polishing were measured, and the results are shown in Table 1.

[0129] [Table 1]

[0130] (1) Abrasive particle surface treatment agent

[0131] F-1: PL-3C (FUSO, cation type)

[0132] F-2: PL-1C (FUSO, cation type)

[0133] G-1:BS-1 LC(FUSO)

[0134] pH adjuster: Select from nitric acid, KOH, and TEA (triethanolamine), each added at 0.03 wt % to 0.1 wt %.

[0135] Referring to Table 1, the polishing slurry composition according to the present invention can ensure high polishing rate and polishing performance for polycrystalline silicon films in the acidic region when the quaternary ammonium cationic monomers represented by Chemical Formula 1 and Chemical Formula 2 are added. That is, it is confirmed that the polishing slurry composition according to the present invention can achieve a high polishing rate for polycrystalline silicon films and a high polishing selectivity for silicon oxide and silicon nitride films compared to the application of the nonionic polymer, anionic polymer, and cationic polymer of the comparative examples.

[0136] Although the embodiments have been described above using limited examples and drawings, those skilled in the art will appreciate that various modifications and variations may be made from the above description. For example, the described techniques may be performed in a different order than described, and / or the described components may be combined or substituted in a different manner than described, or other components or equivalents may be substituted or substituted, and still achieve suitable results. Therefore, the scope of the present invention is not limited to the disclosed embodiments, but is defined by the appended claims and their equivalents.

Claims

1. colloidal silica abrasive particles; a quaternary ammonium cationic monomer; Acidic substances, A polishing slurry composition for polishing polycrystalline silicon, comprising: the colloidal silica abrasive particles have a cationic surface charge; The colloidal silica abrasive particles are particles of a single size ranging from 10 nm to 200 nm, or include mixed particles having two or more different sizes ranging from 10 nm to 200 nm; The quaternary ammonium cationic monomer is a polishing slurry composition including at least one compound represented by the following Chemical Formula 2: 【Chemistry 2】 In the formula 2, R 1 to R 4 are each selected from hydrogen, a linear or branched alkyl group having 1 to 50 carbon atoms, and a linear or branched alkenyl group having 2 to 50 carbon atoms; X is a counterion selected from hydroxide (OH − ), halogen, sulfate (SO 4 2− ), phosphate (PO 4 3− ), nitrate (NO 3 − ), hydrogen sulfate (HSO 4 − ), methyl methanesulfonate (CH 3 SO 3 − ), perchlorate (ClO 4 − ), and hexafluorophosphate (PF 6 − ).

2. 2. The polishing slurry composition of claim 1, wherein the abrasive particles account for 0.0001% to 10% by weight of the slurry composition.

3. 2. The polishing slurry composition of claim 1, wherein the quaternary ammonium cationic monomer is 0.0001% to 0.5% by weight of the composition.

4. the acidic substance comprises an inorganic acid, an organic acid, or both; 2. The polishing slurry composition according to claim 1, wherein the acidic substance is present in an amount of 0.0001% by weight to 1% by weight of the polishing slurry composition.

5. 5. The polishing slurry composition according to claim 4, wherein the inorganic acid comprises at least one selected from the group consisting of sulfuric acid, nitric acid, phosphoric acid, silicic acid, hydrofluoric acid, boric acid, bromic acid, iodic acid, hydrochloric acid, and perchloric acid.

6. the organic acid comprises a monocarboxylic acid, a dicarboxylic acid, or two thereof; The organic acids include citric acid, oxalic acid, propionic acid, stearic acid, pyruvic acid, acetic acid, acetoacetic acid, glyoxylic acid, malic acid, malonic acid, dimethylmalonic acid, maleic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, and phthalic acid.

5. The polishing slurry composition according to claim 4, comprising at least one selected from the group consisting of 2,2-dimethylglutaric acid, lactic acid, isoleucine, butyric acid, succinic acid, 3,3-diethylsuccinic acid, and ascorbic acid.

7. The polishing slurry composition according to claim 4, wherein when two or more kinds of acidic substances are used, the mass ratio of the first acidic substance to the remaining acidic substances is 9:1 to 1:

9.

8. The polishing slurry composition further comprises a basic compound, The basic compound may be ammonia, ammonium methyl propanol (AMP), tetramethyl ammonium hydroxide (TMAH), ammonium hydroxide, potassium hydroxide, sodium hydroxide, magnesium hydroxide, rubidium hydroxide, cesium hydroxide, sodium bicarbonate, sodium carbonate, imidazole, monoethanolamine (MEA), diethanolamine (Diethanolamine), or the like. amine, DEA), triethanolamine (TEA), 1,5-diamino-3-pentanol, 2-dimethylamino-2-methyl-1-propanol, 1-amino-2-propanol, 1-dimethylamino-2-propanol, 1,3-diamino-2-propanol, 3-dimethylamino-1-propanol, 2-amino-1-propanol, 2-dimethylamino-1-propanol, 2-diethylamino-1-propanol, 2-(2-aminoethylamino)ethanol, 2-diethylamino-1-ethanol, 2-ethylamino-1-ethanol, 1-(dimethylamino)2-propanol, N-methyldiethanolamine, N-propyldiethanolamine, N-isopropyldiethanolamine, N-(2-methylpropyl)diethanolamine ethanolamine, N-n-butyldiethanolamine, N-t-butylethanolamine, N-cyclohexyldiethanolamine, 2-(dimethylamino)ethanol, 2-diethylaminoethanol, 2-dipropylaminoethanol, 2-butylaminoethanol, 2-t-butylaminoethanol, 2-cycloaminoethanol, 2-amino-2-pentanol, 2-[bis(2-hydroxyethyl)amino]-2-methyl-1-propanol, 2-[bis(2-hydroxyethyl)amino]-2-propanol, N,N-bis(2-hydroxypropyl)ethanolamine, 2-amino-2-methyl-1-propanol, tris(hydroxymethyl)aminomethane, triisopropanolamine, tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (Tetrapropylammonium hydroxide),hydroxide (TPAH), tetrabutylammonium hydroxide, tetrapentylammonium (TBAH), methyl(trihydroxyethyl)ammonium hydroxide, tributylethylammonium hydroxide, (2-hydroxyethyl)triethylammonium hydroxide ((2-hydroxyethyl), triethylammonium hydroxide 2. The polishing slurry composition according to claim 1, comprising at least one selected from the group consisting of (2-hydroxyethyl)tripropylammonium hydroxide, (2-hydroxyethyl)tripropylammonium hydroxide, and (1-hydroxypropyl)triethylammonium hydroxide.

9. 2. The polishing slurry composition of claim 1, wherein the pH of the slurry composition is 2 to 11.

10. 2. The polishing slurry composition according to claim 1, wherein the polishing rate of the polishing slurry composition for a polycrystalline silicon film is 2000 Å / min or more.

11. 2. The polishing slurry composition according to claim 1, wherein the polishing slurry composition has a pH of 3 to 5 or a pH of 9 to 11, and a selectivity of the polycrystalline silicon film to the silicon nitride film, the silicon oxide film, or the film containing both of them is 10:1 to 1000:1.

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