Polishing slurry composition

Abstract

The present invention relates to a polishing slurry composition. According to one aspect of the present invention, a polishing slurry composition is provided, comprising polishing particles; a dispersant; a pH buffer; and a dishing inhibitor comprising at least any one selected from the group consisting of saccharides, amino acids, and mixtures thereof.

Description

Technical Field

[0001] The present invention relates to a polishing slurry composition. More specifically, the polishing slurry composition can minimize the amount of dishing occurring in low-step portions of a patterned wafer having a relatively large width. Background Art

[0002] Chemical Mechanical Polishing (CMP) is performed by applying a slurry containing polishing particles to a substrate using a polishing pad mounted on a polishing device. The polishing particles are subjected to pressure from the polishing device, mechanically polishing the surface. Chemical components in the polishing slurry react with the substrate surface, chemically removing portions of the substrate's surface.

[0003] The chemical mechanical polishing process is used in the planarization process of interlayer insulating films, shallow trench isolation (STI) processes, and the formation of plugs and buried metal wiring in the semiconductor device manufacturing process.

[0004] The STI process etches the isolation region to form a trench, then introduces CMP planarization technology after oxide deposition. This requires selective polishing to increase the polishing rate of the oxide layer, which serves as an insulating film, and decrease the polishing rate of the nitride layer, which serves as a diffusion barrier.

[0005] However, when the selective polishing characteristics are improved, that is, when the oxide film has high selectivity relative to the nitride film, the oxide film may be dented (Dishing), which may cause current leakage and reliability degradation in the finished semiconductor chip due to electron tunneling.

[0006] To this end, a slurry composition has been developed that improves the polishing selectivity of the oxide film relative to the nitride film while reducing the depression of the oxide film. However, the existing slurry composition is only effective for the low-step portion of the pattern with a width of less than 500 μm, and its effect on reducing the depression of the low-step portion of the pattern with a wider width is very limited.

[0007] Therefore, there is a need to develop a polishing slurry composition that can improve the polishing selectivity of an oxide film relative to a nitride film while suppressing dishing of the oxide film in a low-step portion of a pattern wafer having a relatively large width.

[0008] The content of the above background technology is what the inventor mastered or learned in the process of developing the present invention, and should not be understood as necessarily being the general known technology disclosed before applying for the present invention. Summary of the Invention

[0009] Problems to be solved by the invention

[0010] The present invention aims to solve the above problems and provide a polishing slurry composition that can improve the polishing selectivity of an oxide film relative to a nitride film while minimizing oxide film dishing in a low-step portion of a pattern wafer having a large width.

[0011] However, the technical problems to be solved by the present invention are not limited to the above-mentioned subjects, and other unmentioned subjects will be clearly understood by those skilled in the art through the following description.

[0012] Technical means to solve the problem

[0013] One aspect of the present invention provides a polishing slurry composition comprising: polishing particles; a dispersant; a pH buffer; and a dishing inhibitor, comprising at least any one selected from the group consisting of saccharides, amino acids, and mixtures thereof.

[0014] According to one embodiment, the polishing particles include at least any one selected from the group consisting of metal oxides, metal oxides coated with organic or inorganic substances, and metal oxides in a colloidal state, and the metal oxides include at least any one selected from the group consisting of silicon dioxide, ceria, zirconium oxide, aluminum oxide, titanium dioxide, barium titanium dioxide, germanium oxide, manganese oxide, and magnesium oxide.

[0015] According to one embodiment, the primary particle size of the polishing particles is 5 nm to 150 nm, and the secondary particle size of the polishing particles is 30 nm to 300 nm.

[0016] According to one embodiment, the polishing particles may be in a dispersed state such that surfaces of the polishing particles have positive charges.

[0017] According to one embodiment, the content of the polishing particles is 0.1 wt % to 10 wt %.

[0018] According to one embodiment, the dispersant includes at least one selected from the group consisting of picolinic acid, dipicolinic acid, benzoic acid, phenylacetic acid, naphthoic acid, mandelic acid, nicotinic acid, dinicotinic acid, isonicotinic acid, quinolinic acid, anthranilic acid, fusaric acid, phthalic acid, isophthalic acid, terephthalic acid, toluic acid, salicylic acid, nitrobenzoic acid, and pyridinedicarboxylic acid.

[0019] According to one embodiment, the content of the dispersant is 0.1 wt % to 10 wt %.

[0020] According to one embodiment, the pH buffer comprises amino acids, and the amino acids include at least any one selected from the group consisting of histidine, lysine, and arginine.

[0021] According to one embodiment, the content of the pH buffer is 0.01 wt % to 5 wt %.

[0022] According to one embodiment, the carbohydrate compound includes at least any one selected from the group consisting of monosaccharides, polysaccharides, sugar alcohols and salts thereof.

[0023] According to one embodiment, the carbohydrate compound includes four or more hydroxyl groups (-OH).

[0024] According to one embodiment, the carbohydrate compound includes a hydroxyl group and an amine group.

[0025] According to one embodiment, the depression inhibitor includes at least one selected from the group consisting of proline, ribose, glucose, sorbitol, N-acetyl-D-glucosamine, and glucosamine hydrochloride.

[0026] According to one embodiment, the content of the dishing inhibitor is 0.001 wt % to 1 wt %.

[0027] According to one embodiment, the polishing slurry composition further includes a pH adjuster, wherein the pH adjuster includes lactic acid, pimelic acid, malic acid, malonic acid, maleic acid, acetic acid, adipic acid, oxalic acid, succinic acid, tartaric acid, citric acid, glutaric acid, glycolic acid, formic acid, fumaric acid, propionic acid, butyric acid, hydroxybutyric acid, aspartic acid, itaconic acid, tricarballylic acid, suberic acid, sebacic acid, stearic acid, pyruvic acid, acetoacetic acid, and acetic acid. At least one selected from the group consisting of hydroxybenzoic acid, glyoxylic acid, azelaic acid, caprylic acid, lauric acid, myristic acid, valeric acid, and palmitic acid.

[0028] According to one embodiment, the polishing slurry composition is a positive electrode slurry composition having a positive charge.

[0029] According to one embodiment, the pH of the polishing slurry composition is 4 to 6.

[0030] According to one embodiment, the polishing slurry composition is used to polish a pattern wafer having a width of 2000 μm or more, and the amount of dishing on the low step portion of the pattern wafer is the following.

[0031] According to one embodiment, the polishing rate of the oxide film (SiO2) of the polishing slurry composition is As described above, the polishing selectivity of the oxide film (SiO 2 ) relative to the nitride film (SiN), that is, the polishing rate of the oxide film (SiO 2 ) / the polishing rate of the nitride film (SiN) is 200 or more.

[0032] [Effects of the Invention]

[0033] The polishing slurry composition of the present invention has the effect of minimizing the dishing of the oxide film in the low-step portion of a pattern wafer having a large width while improving the polishing selectivity of the oxide film relative to the nitride film. DETAILED DESCRIPTION

[0034] Below, the embodiment will be described in detail. It should be understood that various changes can be made to the embodiment, and the scope of the present application is not limited to the following embodiment. All changes made to the embodiment, and their equivalents and even their substitutes are within the scope of the present invention.

[0035] The terms used in the embodiments are intended only to describe specific embodiments and are not intended to limit the scope. Unless otherwise specified in the context, singular expressions include the plural. In this specification, terms such as "including" or "having" are used to express the presence of features, numbers, steps, operations, constituent elements, accessories, or combinations thereof described in the specification, and do not exclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, constituent elements, accessories, or combinations thereof.

[0036] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the ordinary meanings understood by those skilled in the art. Commonly used terms, as defined in dictionaries, should be understood as having the meanings in the relevant technical context and, unless explicitly defined in this specification, should not be interpreted as idealizing or formalizing the meaning.

[0037] Furthermore, in the process of describing the embodiments, when it is determined that a detailed description of a related known technology would unnecessarily obscure the embodiments, the detailed description will be omitted.

[0038] Furthermore, when describing the constituent elements of the embodiments, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only used to distinguish one constituent element from other constituent elements and are not used to limit the nature or order of the corresponding constituent elements. For example, a first constituent element may be referred to as a second constituent element, and similarly, a second constituent element may be referred to as a first constituent element. In addition, it should be understood that when the specification states that a constituent element is "connected," "coupled," or "in contact with" another constituent element, a third constituent element may be "connected," "coupled," or "in contact with" the first constituent element and the second constituent element, even though the first constituent element can be directly connected, coupled, or in contact with the second constituent element.

[0039] When a component has the same function as a component of a certain embodiment, the same name is used to describe the component in the other embodiment. Unless a counterexample is mentioned, the description of a certain embodiment is applicable to other embodiments, and detailed description of the repeated content is omitted.

[0040] One aspect of the present invention provides a polishing slurry composition comprising: polishing particles; a dispersant; a pH buffer; and a dishing inhibitor comprising at least any one selected from the group consisting of saccharides, amino acids, and mixtures thereof.

[0041] The polishing slurry composition of the present invention includes a dishing inhibitor, thereby having the effect of minimizing dishing of the oxide film in a low-step portion of a pattern wafer having a large space while improving the polishing selectivity of the oxide film relative to the nitride film.

[0042] The low-step portion of the pattern wafer refers to a recessed portion of a step difference.

[0043] According to one embodiment, the polishing particles include at least one selected from the group consisting of metal oxides, metal oxides coated with organic or inorganic substances, and colloidal metal oxides. The metal oxides include at least one selected from the group consisting of silicon dioxide, ceria, zirconium oxide, aluminum oxide, titanium dioxide, barium titanium dioxide, germanium oxide, manganese oxide, and magnesium oxide. For example, the polishing particles may be colloidal ceria.

[0044] The polishing particles provide high dispersion stability, promote oxidation of an inorganic oxide film as a polishing target film, can easily polish the inorganic oxide film, and achieve high polishing characteristics while minimizing defects such as scratches.

[0045] According to one embodiment, the polishing particles can be prepared by a liquid phase method. Liquid phase methods include sol-gel methods, in which a polishing particle precursor undergoes a chemical reaction in an aqueous solution to produce crystals, thereby producing microparticles; co-precipitation methods, in which polishing particle ions are precipitated in an aqueous solution; and hydrothermal synthesis methods, in which polishing particles are formed under high temperature and high pressure.

[0046] According to one embodiment, the polishing particles are in a dispersed state, so that the surfaces of the polishing particles have a positive charge. When the polishing particles are prepared using a liquid phase method, the polishing particles can be dispersed so that the surfaces of the polishing particles have a positive charge.

[0047] The polishing particles may include single crystal particles. Compared with polycrystalline polishing particles, the use of single crystal polishing particles can reduce scratches and improve dishing.

[0048] The shape of the polishing particles may be at least any one selected from the group consisting of spherical, angular, needle-shaped, and plate-shaped, and is preferably spherical.

[0049] In addition to single-size particles, the polishing particles can be mixed particles with a multi-dispersed particle distribution. For example, a bimodal particle distribution can be achieved by mixing polishing particles of two different average particle sizes, or a trimodal particle distribution can be achieved by mixing polishing particles of three different average particle sizes. Alternatively, a multi-dispersed particle distribution can be achieved by mixing polishing particles of four or more different average particle sizes. By mixing larger polishing particles with relatively smaller ones, better dispersion can be achieved, and scratches on the wafer surface can be reduced.

[0050] According to one embodiment, the polishing particles may include primary particles, secondary particles, or both.

[0051] According to one embodiment, the primary particle size of the polishing particles is 5 nm to 150 nm, and the secondary particle size of the polishing particles may be 30 nm to 300 nm.

[0052] The size of the polished particles refers to the average particle size of a plurality of particles within a field of view, which can be measured by scanning electron microscopy analysis or dynamic light scattering.

[0053] When the primary particle size of the polishing particles is less than the above range, the polishing rate may be significantly reduced. When the primary particle size exceeds the above range, the possibility of scratches may increase.

[0054] When the secondary particle size of the polishing particles is less than the above range, the polishing rate will be reduced; when it exceeds the above range, it will be difficult to adjust the selectivity due to excessive polishing, and the oxide film depression will be aggravated.

[0055] According to one embodiment, the polishing particles may be present in an amount of 0.1 wt % to 10 wt %.

[0056] Preferably, it may be 0.5 wt% to 5 wt%, more preferably, it may be 0.5 wt% to 1 wt%.

[0057] When the content of the polishing particles is less than the range, the polishing speed will be reduced; when it exceeds the range, defects such as chips or scratches will appear due to over-polishing, and as the number of polishing particles increases, the adsorption of particles remaining on the surface will cause surface defects.

[0058] According to one embodiment, the dispersant may include at least any one selected from the group consisting of picolinic acid, dipicolinic acid, benzoic acid, phenylacetic acid, naphthoic acid, mandelic acid, nicotinic acid, dinicotinic acid, isonicotinic acid, quinolinic acid, anthranilic acid, fusaric acid, phthalic acid, isophthalic acid, terephthalic acid, toluic acid, salicylic acid, nitrobenzoic acid, and pyridinedicarboxylic acid.

[0059] According to one embodiment, the content of the dispersant may be 0.1 wt % to 10 wt %.

[0060] Preferably, it may be 0.1 wt% to 5 wt%, more preferably, it may be 0.5 wt% to 1 wt%.

[0061] When the content of the dispersant is less than the above range, the polishing particles cannot be dispersed, which reduces the polishing performance and makes it difficult to achieve the expected polishing selectivity.

[0062] On the contrary, when the above range is exceeded, the dispersion stability is reduced due to aggregation, thereby causing defects on the surface of the film to be polished, and significantly reducing the polishing rate.

[0063] According to one embodiment, the pH buffer comprises amino acids, and the amino acids include at least any one selected from the group consisting of histidine, lysine, and arginine.

[0064] The pH buffering agent plays a role in ensuring the dispersibility and dispersion stability of the polishing particles, and can prevent the problem of dispersion stability reduction caused by additives.

[0065] The amino acid has the advantage that it can maintain the polishing speed and can achieve a sufficient pH buffering effect even in a small amount.

[0066] According to one embodiment, the content of the pH buffer may be 0.01 wt % to 5 wt %.

[0067] Preferably, it may be 0.01 wt% to 1 wt%, and more preferably, it may be 0.1 wt% to 0.3 wt%.

[0068] When the pH buffering agent is included in an amount less than the above range, the dispersion stability may be reduced, and thus the expected polishing performance may not be achieved, thereby reducing the polishing rate.

[0069] On the contrary, when the pH buffer exceeds the above range, the excess pH buffer aggregates and reduces dispersion stability, thereby causing micro defects or scratches on the film to be polished and reducing the polishing speed.

[0070] The polishing slurry composition includes a dishing inhibitor, wherein the dishing inhibitor includes at least any one selected from the group consisting of saccharide compounds, amino acids, and mixtures thereof.

[0071] According to one embodiment, the amino acid includes at least any one selected from the group consisting of proline, glycine, alanine, methionine, valine, isoleucine, and leucine.

[0072] The dishing inhibitor contains a compound including a hydroxyl functional group (—OH) and functions to inhibit dishing of an oxide film.

[0073] That is, when simultaneously polishing a nitride film and an oxide film in a polishing slurry composition, the dishing inhibitor suppresses dishing of the oxide film while ensuring a high polishing selectivity of the oxide film relative to the nitride film.

[0074] According to one embodiment, the carbohydrate compound includes at least any one selected from the group consisting of monosaccharides, polysaccharides, sugar alcohols and salts thereof.

[0075] The monosaccharide includes monosaccharides and monosaccharide derivatives.

[0076] According to one embodiment, the monosaccharide may include at least any one selected from the group consisting of glucose, ribose, arabinose, lyxose, maltose, allose, altrose, gulose, xylulose, talose, ribulose, idose, lactose, xylose, galactose, fructose, and derivatives thereof.

[0077] For example, N-acetyl-D-glucosamine can be used as the monosaccharide derivative.

[0078] The polysaccharide includes polysaccharides and polysaccharide derivatives.

[0079] According to one embodiment, the polysaccharide may include gellan gum, rhamnose gum, welangum, xanthan gum, guar gum, karayagum, Arabic gum, locust beangum, tragacanth gum, ghatti gum, tara gum, konjac gum, algin, agar, carrageenan, furcellaran, curdlan, alginic acid, casein, tatagum, tamarind gum, pectin, glucomannan, arabinogalactan, pullulan and acacia gum. At least any one selected from the group consisting of gum).

[0080] According to one embodiment, the sugar alcohol may include at least any one selected from the group consisting of maltitol, lactitol, threitol, erythritol, ribitol, xylitol, arabitol, adonitol, sorbitol, talitol, isomalt, mannitol, iditol, allodulcitol, dulcitol, sedoheptitol and perseitol.

[0081] The salts of monosaccharides, polysaccharides and sugar alcohols refer to salts of monosaccharides, salts of polysaccharides and salts of sugar alcohols. For example, glucosamine hydrochloride can be used as the salt of monosaccharides.

[0082] According to one embodiment, the saccharide compound may include four or more hydroxyl groups (-OH).

[0083] When four or more hydroxyl groups are included, a high polishing selectivity ratio of the oxide film to the nitride film can be achieved while minimizing oxide film dishing at low step portions of a wide pattern wafer.

[0084] According to one embodiment, the saccharide compound may include six or more hydroxyl groups (—OH). In this case, the polishing selectivity of the oxide film relative to the nitride film may be maximized.

[0085] According to one embodiment, the carbohydrate compound may include a hydroxyl group and an amine group.

[0086] The compound including both the hydroxyl group and the amine group can maximize the polishing selectivity of the oxide film relative to the nitride film while minimizing the oxide film recessing at the low step portion of a wide pattern wafer.

[0087] According to one embodiment, the depression inhibitor may include at least any one selected from the group consisting of proline, ribose, glucose, sorbitol, N-acetyl-D-glucosamine, and glucosamine hydrochloride.

[0088] According to one embodiment, the content of the dishing inhibitor may be 0.001 wt % to 1 wt %.

[0089] Preferably, it may be 0.01 wt% to 0.8 wt%, more preferably, it may be 0.08 wt% to 0.5 wt%, and most preferably, it may be 0.08 wt% to 0.3 wt%.

[0090] When the content of the dishing inhibitor is less than the above range, the performance of suppressing dishing of the oxide film is reduced, and the polishing selectivity of the oxide film to the nitride film is reduced.

[0091] On the contrary, when the dishing inhibitor is contained in an amount outside the range, there occurs a problem in that the polishing speed is significantly reduced.

[0092] According to one embodiment, the polishing slurry composition further includes a pH adjuster, and the pH adjuster may include lactic acid, pimelic acid, malic acid, malonic acid, maleic acid, acetic acid, adipic acid, oxalic acid, succinic acid, tartaric acid, citric acid, glutaric acid, glycolic acid, formic acid, fumaric acid, propionic acid, butyric acid, hydroxybutyric acid, aspartic acid, itaconic acid, tricarballylic acid, suberic acid, sebacic acid, stearic acid, pyruvic acid, acetoacetic acid, ... At least one selected from the group consisting of hydroxybenzoic acid, glyoxylic acid, azelaic acid, caprylic acid, lauric acid, myristic acid, valeric acid, and palmitic acid.

[0093] The pH adjuster is added in an amount sufficient to adjust the pH of the polishing slurry composition.

[0094] According to one embodiment, the polishing slurry composition can be concentrated or diluted before use. In addition, the polishing slurry composition further includes a solvent.

[0095] According to one embodiment, the polishing slurry composition may be a positive electrode slurry composition having a positive charge.

[0096] The polishing slurry composition can have a positive zeta potential of +10 mV to +60 mV.

[0097] The positively charged polishing particles can maintain high dispersion stability, prevent aggregation of polishing particles, and reduce the occurrence of micro scratches.

[0098] According to one embodiment, the pH of the polishing slurry composition may be 4 to 6. Preferably, the pH may be 4 to 5.

[0099] When the pH range is exceeded, dispersibility is reduced and particle aggregation is induced, thereby causing scratches or defects.

[0100] According to one embodiment, the polishing slurry composition is used to polish a pattern wafer having a width of 2000 μm or more, and the amount of dishing on the low step portion of the pattern wafer is the following.

[0101] The low-step portion may refer to a recessed portion with a step difference.

[0102] Furthermore, the amount of depression refers to the height difference between the convex portion and the concave portion of the step difference.

[0103] According to one embodiment, the polishing slurry composition can polish a patterned wafer having a width of 2700 μm or greater.

[0104] According to one embodiment, the amount of dishing in the low step portion of the pattern wafer is the following.

[0105] The polishing slurry composition of the present invention has an effect of minimizing oxide film dishing in a low-step portion of a pattern wafer having a large space.

[0106] That is, the occurrence of defects is prevented by minimizing the amount of recessing of the oxide film, thereby improving the performance and reliability of the semiconductor device.

[0107] According to one embodiment, the polishing rate of the polishing slurry composition for the oxide film (SiO2) is As described above, the polishing selectivity ratio of the oxide film (SiO 2 ) to the nitride film (SiN) (polishing rate of the oxide film (SiO 2 ) / polishing rate of the nitride film (SiN)) is 200 or more.

[0108] The polishing slurry composition of the present invention has a higher polishing selectivity for oxide films than for nitride films.

[0109] Especially in At the above high oxide film polishing speed, a high selectivity ratio for the oxide film can also be achieved.

[0110] According to one embodiment, the polishing slurry composition is suitable for polishing a thin film including at least one of an insulating film and an inorganic oxide film.

[0111] The insulating film includes at least any one selected from the group consisting of a silicon oxide film, a silicon nitride film, and a polysilicon film.

[0112] The inorganic oxide film includes fluorine doped tin oxide (FTO, fluorine doped tin oxide, SnO2:F), indium tin oxide (ITO, indium tin oxide), indium zinc oxide (IZO, indium zinc oxide), indium gallium zinc oxide (IGZO, indium gallium zinc oxide), aluminum doped zinc oxide (AZO, Al-doped ZnO), aluminum gallium zinc oxide (AGZO, Aluminum Gallium Zinc Oxide), gallium doped zinc oxide (GZO, Ga-doped ZnO), indium zinc tin oxide (IZTO, Indium Zinc Tin Oxide), indium aluminum zinc oxide (IAZO, Indium Aluminum Zinc Oxide), indium gallium zinc oxide (IGZO, Indium Gallium Zinc Oxide), indium gallium tin oxide (IGTO, Indium Gallium Tin Oxide), antimony tin oxide (ATO, Antimony Tin Oxide), gallium zinc oxide (GZO, Gallium Zinc Oxide), indium zinc oxynitride (IZON, IZO Nitride), SnO2, ZnO, IrOx, RuOx and NiO.

[0113] According to one embodiment, the polishing slurry composition is suitable for polishing semiconductor devices, display devices, or both.

[0114] According to one embodiment, the polishing slurry composition is suitable for a shallow trench isolation (STI) process.

[0115] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

[0116] However, the following embodiments are only used to illustrate the present invention, and the content of the present invention is not limited to the following embodiments.

[0117] <Example 1>

[0118] 4 wt % of colloidal cerium dioxide as polishing particles and 0.5 wt % of picolinic acid as a dispersant were mixed to prepare a polishing particle dispersion.

[0119] 0.1 wt % of histidine as a pH buffer and 0.1 wt % of proline as a dishing inhibitor were added to the polishing particle dispersion, and a pH adjuster was used to prepare a polishing slurry composition having a pH of 4.5.

[0120] <Example 2>

[0121] A polishing slurry composition was prepared in the same manner as in Example 1, except that ribose was used as the dishing inhibitor.

[0122] <Example 3>

[0123] A polishing slurry composition was prepared in the same manner as in Example 1, except that glucose was used as the dishing inhibitor.

[0124] <Example 4>

[0125] A polishing slurry composition was prepared in the same manner as in Example 1, except that sorbitol was used as the dishing inhibitor.

[0126] <Example 5>

[0127] A polishing slurry composition was prepared in the same manner as in Example 1, except that N-acetyl-D-glucosamine was used as the dishing inhibitor.

[0128] <Example 6>

[0129] A polishing slurry composition was prepared in the same manner as in Example 1, except that glucosamine hydrochloride was used as the dishing inhibitor.

[0130] <Comparative Example 1>

[0131] A polishing slurry composition was prepared in the same manner as in Example 1, except that no dishing inhibitor was added.

[0132] <Experimental Example>

[0133] Using the polishing slurry compositions prepared in the examples and comparative examples, a CMP process was performed at the following polishing rate.

[0134] Polishing conditions

[0135] 1. Polishing device: AP-300 (CTS company)

[0136] 2. Wafer: 300mm PE-TEOS, LP-SiN, STI patterned wafer

[0137] 3. Carrier pressure: 4psi

[0138] 4. Spindle speed: 87 rpm

[0139] 5. Platen speed: 93 rpm

[0140] 6. Flow rate: 250ml / min

[0141] 7. Polishing time: 60s

[0142] Table 1 shows the type of dishing inhibitor used in each polishing slurry composition, the polishing rate (RR) of oxide and nitride films, the polishing selectivity, the degree of oxide film dishing, and the measurement results of the degree of nitride film loss.

[0143] Table 1

[0144]

[0145]

[0146] Referring to Table 1, it can be seen that in the embodiment, while showing a polishing selectivity of more than 200, the amount of concavity of the oxide film in the low step portion of the pattern with a width of more than 2700 μm is also Below, the nitride film loss is Compared with the slurry composition of Comparative Example 1 which does not use a dishing inhibitor, it can be seen that the polishing selectivity is increased, and the amount of dishing in the oxide film and the amount of loss in the nitride film are reduced. In particular, when a saccharide compound containing four or more hydroxyl groups (-OH) is used as a dishing inhibitor (Examples 2, 3, and 4), it can be achieved. The following amount of dents occurs.

[0147] Furthermore, when a dishing suppressor having 4 or more hydroxyl groups (-OH) and an amino group is included (Examples 5 and 6), the polishing selectivity is increased, and the amount of oxide film dishing and nitride film loss can be further reduced.

[0148] In summary, the embodiments have been described above, and persons of ordinary skill in the art will be able to make various modifications and variations based on the descriptions. For example, the described techniques may be performed in a different order than the illustrated method, and / or the described components may be combined or combined in a different manner than the illustrated method, or replaced or substituted with other components or equivalents, and appropriate results may still be achieved.

[0149] Accordingly, other embodiments, other examples, and equivalents of the claims are within the scope of the appended claims.

Claims

1. A polishing slurry composition, characterized in that include: Cerium dioxide polishing particles; dispersants; pH buffers; as well as Sag Inhibitor, wherein the dispersant comprises at least one selected from the group consisting of picolinic acid, pyridinedicarboxylic acid, benzoic acid, phenylacetic acid, naphthoic acid, mandelic acid, nicotinic acid, nicotinic acid, isonicotinic acid, quinolinic acid, anthranilic acid, fusaric acid, phthalic acid, isophthalic acid, terephthalic acid, methylbenzoic acid, salicylic acid, and nitrobenzoic acid, The pH buffer comprises at least one selected from the group consisting of histidine, lysine and arginine, The depression inhibitor includes at least one selected from the group consisting of N-acetyl-D-glucosamine and glucosamine hydrochloride, The content of the dishing inhibitor is 0.001 wt% or more and less than 1 wt% And wherein the pH of the polishing slurry composition is 4 to 6.

2. The polishing slurry composition according to claim 1, wherein The primary particle size of the polishing particles is 5 nm to 150 nm, The secondary particle size of the polishing particles is 30 nm to 300 nm.

3. The polishing slurry composition according to claim 1, wherein The content of the polishing particles is 0.1 wt % to 10 wt %.

4. The polishing slurry composition according to claim 1, wherein The content of the dispersant is 0.1 wt % to 10 wt %.

5. The polishing slurry composition according to claim 1, wherein The content of the pH buffer is 0.01 wt % to 5 wt %.

6. The polishing slurry composition according to claim 1, wherein Also includes pH adjusters, The pH adjuster includes at least one selected from the group consisting of lactic acid, pimelic acid, malic acid, malonic acid, maleic acid, acetic acid, adipic acid, oxalic acid, succinic acid, tartaric acid, citric acid, glutaric acid, glycolic acid, formic acid, fumaric acid, propionic acid, butyric acid, hydroxybutyric acid, aspartic acid, itaconic acid, tricarballylic acid, suberic acid, sebacic acid, stearic acid, pyruvic acid, acetoacetic acid, glyoxylic acid, azelaic acid, caprylic acid, lauric acid, myristic acid, valeric acid and palmitic acid.

7. The polishing slurry composition according to claim 1, wherein It is a positive electrode slurry composition with a positive charge.

8. The polishing slurry composition according to claim 1, wherein Polishing of patterned wafers with a width of 2000㎛ or more, The amount of concavity generated in the low-step portion of the pattern wafer is less than 1600 Å.

9. The polishing slurry composition according to claim 1, wherein The polishing speed of SiO2 oxide film is above 2000 Å / min. The polishing selectivity ratio of the SiO2 oxide film to the SiN nitride film, that is, the polishing rate of the SiO2 oxide film / the polishing rate of the SiN nitride film is 200 or more.

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