Abrasive particles and abrasive slurry composition using same

Abstract

The present invention provides a surface-modified polishing particle and a polishing slurry composition comprising the same, and the polishing slurry composition comprises the surface-modified polishing particle. According to the present invention, the ratio of modifier content / silicon oxide content, the ratio of carbon content / silicon oxide content of a modifier in a slurry after centrifugal separation, or the isoelectric point (IEP) difference of modified abrasive particles in the slurry before and after centrifugal separation are adjusted to a specific range so as to improve the polishing performance of an insulating film and a metal film and have high-temperature stability.

Description

Technical Field

[0001] The present invention relates to abrasive grains suitable for polishing a metal barrier layer for through-silicon via (TSV) and an abrasive slurry composition using the same. Background Art

[0002] In the semiconductor manufacturing process, a chip applying integrated circuit technology includes millions of functional components such as transistors, capacitors, and resistors. These individual components are interconnected by wiring patterned into a certain shape to form a circuit. As the generations progress, integrated circuits are becoming increasingly miniaturized, so the functions of a single chip are becoming stronger.

[0003] However, since simply reducing the component size is limited, recently, active research has been conducted on a multi-layer wiring structure in which each component is formed into multiple layers. A representative method is the through silicon via (TSV) method. In this method, after drilling holes in stacked silicon wafers or the like, a metal such as copper is filled into the holes to form through electrodes.

[0004] The TSV method is a packaging technology that can shorten the connection length between semiconductor packages, so it is gradually being applied to high-performance, ultra-small semiconductors. However, the TSV method has several technical difficulties, one of which is that the chemical mechanical polishing process for filling the metal requires more time than the known chemical mechanical polishing process.

[0005] To solve the above disadvantages, it is necessary to develop a chemical mechanical polishing slurry composition that can polish at high speed by increasing the polishing rate and selectivity of the polishing slurry for an insulating film of a copper film or a tungsten film.

[0006] However, the slurries commercially available or developed so far are not sufficient to meet all these requirements. Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] In this specification, it is intended to provide abrasive grains that improve the polishing performance of an insulating film and a metal film and have high-temperature stability.

[0009] Furthermore, in this specification, it is intended to provide an abrasive slurry composition that contains the above abrasive grains, has improved high-temperature stability, and is easily stored for a long time without being affected by the ambient temperature.

[0010] Means for Solving the Problems

[0011] In this specification, an abrasive grain is provided that satisfies the following formula 1.

[0012] [Formula 1]

[0013] (Carbon content after centrifugation / Abrasive particle content) × 10000 = 2 to 285;

[0014] In the above formula (1), the carbon content after centrifugation is the carbon content on the surface of the abrasive particles measured using a carbon analyzer based on the total weight of the abrasive particle solids obtained after centrifuging the slurry containing the surface-modified abrasive particles for 10 minutes, and the abrasive particle content is the content of the surface-modified abrasive particles contained in the slurry.

[0015] In addition, the present specification provides a polishing slurry composition containing the above abrasive particles and a solvent.

[0016] Hereinafter, the present invention will be described in more detail. The terms or words used in the present specification and claims should not be construed as limited to the ordinary meaning or the meaning in the dictionary, but should be interpreted in accordance with the meaning and concept conforming to the technical idea of the present invention based on the principle that the inventor can appropriately define the concept of the terms in order to describe his invention in the best way.

[0017] In addition, "comprising" used in the present specification means that there is a certain characteristic, field, integer, step, operation, element and / or component, and does not exclude the existence of other characteristics, fields, integers, steps, operations, elements and / or components.

[0018] Hereinafter, the abrasive particles according to an embodiment of the present invention and a polishing slurry composition containing the abrasive particles will be described in more detail.

[0019] The present invention provides surface-modified abrasive particles and a polishing slurry composition containing the abrasive particles, characterized in that by surface-modifying the abrasive particles, the ratio of the carbon content of the abrasive particles after centrifugation to the abrasive particle content is adjusted to a specific range, thereby improving the polishing performance of the insulating film and the metal film and having high-temperature stability.

[0020] The abrasive particles according to the present invention are not particularly limited, but may include, for example, silicon oxide, cerium oxide, alumina, zirconia, etc. The above abrasive particles may refer to surface-modified abrasive particles, specifically, abrasive particles whose surface is modified by a modifier. In the present invention, when using surface-modified abrasive particles, the polishing rate of the insulating film relative to the metal film can be increased, the selectivity ratio between the metal film and the insulating film can be increased, but dishing can be reduced.

[0021] According to an embodiment of the present invention, abrasive particles can be provided that satisfy the following formula (1).

[0022] [Formula (1)]

[0023] (Carbon content after centrifugation / Abrasive particle content) × 10000 = 2 to 285;

[0024] In the above formula (1), the carbon content after centrifugation is the carbon content on the surface of the ground particles measured using a carbon analyzer based on the total weight of the ground particle solids obtained after centrifuging the slurry containing the surface-modified ground particles for 10 minutes. The ground particle content is the content of the surface-modified ground particles contained in the slurry.

[0025] For example, the carbon analyzer may be the ELEMENTRAC CS-d of ELTRA Corporation.

[0026] For example, the value of the above formula (1) may be 2 to 285, 5 to 280, 15 to 280, 5 to 200, 10 to 150, or 200 to 285. If the value of the above formula (1) is less than 2, the content of the modifier decreases relative to the ground particles, and there is a problem that the improvement of the grinding performance is insufficient. If the value of the above formula (1) is greater than 285, the particle size stability decreases at high temperatures, and there is a problem that the number of defects increases.

[0027] In the above formula (1), the carbon content after centrifugation of the ground particles may be obtained by centrifuging the grinding slurry composition containing the surface-modified ground particles, removing the supernatant, refilling deionized water (DIW), dispersing the precipitate by ultrasonication for 1 hour, repeating this method 5 to 10 times, drying the precipitated particles, and measuring the carbon content contained in the ground particles in a powder state using a carbon analyzer (ELEMENTRAC CS-d of ELTRA Corporation).

[0028] More specifically, the carbon content after centrifugation may be the carbon content contained in the surface of the total weight (100% by weight) of the ground particle solids obtained by centrifugation after surface modification, that is, the carbon content (% by weight) of the surface modifier bound to the ground particles.

[0029] For example, the above centrifugation may be carried out under the conditions of 4°C, 20,000 rpm, and 10 to 30 minutes, and the first centrifugation may be carried out for 30 minutes.

[0030] According to another embodiment of the present invention, the above ground particles may be ground particles that satisfy the following formula (2).

[0031] [Formula (2)]

[0032] (Modifier content / Ground particle content) × 10,000 = 10 to 1240;

[0033] In the above formula (2), for example, the above modifier content may be the content of the modifier added when preparing the surface-modified abrasive grains, or the content of the modifier present on the surface of the abrasive grains after surface modification. The above abrasive grain content may be the content of the surface-modified abrasive grains contained in the slurry containing the surface-modified abrasive grains. The content of the modifier present on the surface of the abrasive grains after the above surface modification may be the content of the modifier measured based on 100% by weight of the abrasive grain solid obtained by centrifuging the slurry containing the surface-modified abrasive grains.

[0034] At this time, in the present invention, the content of the modifier present on the surface of the abrasive grains after the above surface modification may refer to the carbon content bound to the surface of the above abrasive grains with the dried abrasive grains obtained by centrifuging the slurry containing the surface-modified abrasive grains for 10 minutes as the object. Therefore, the content of the above modifier may include the carbon content after centrifugation of formula (1). For the above carbon content, a carbon analyzer can be used for measurement.

[0035] In the above formula (2), the abrasive grains may be abrasive grains whose surfaces are modified with a modifier. Therefore, similar to formula (1), the above abrasive grain content is the content of the surface-modified abrasive grains contained in the slurry containing the surface-modified abrasive grains.

[0036] In the present invention, the abrasive grain solid obtained after the above centrifugation may be a dried solid, and its drying temperature is not limited. For example, the above abrasive grain solid may be dried at a temperature of about 30 to 60 °C.

[0037] The value of the above formula (2) may be 10 to 1240, 20 to 1218, 64 to 1218, 20 to 870, 45 to 650, or 500 to 1240. Within the range of the value of the above formula (2), the grinding performance is excellent, and the particle size stability at high temperature is excellent, so no defects will occur.

[0038] For example, relative to 100 parts by weight of the above abrasive grains, the content of the above modifier may be 0.0001 to 5 parts by weight, or 0.0004 to 3.72 parts by weight, or 0.0006 to 2.7 parts by weight.

[0039] If the content of the above modifier is within the above range, the abrasive grains are sufficiently modified, the grinding performance is high, and the particle size stability at high temperature will not decrease.

[0040] According to another embodiment of the present invention, the above abrasive grains may have a difference in isoelectric point (IEP, The isoelectric point) before and after centrifugation of 1 or less, or 0.1 to 1 or less, or 0.1 to 0.8.

[0041] When the change value of IEP before and after centrifugal separation is 1 or more, it indicates that the surface of the abrasive particles is not modified or slightly modified, which means that the unmodified modifier on the surface of the abrasive particles is removed in the supernatant through centrifugal separation.

[0042] Compared with the prior art, the abrasive particles of the present invention improve the particle dispersibility, and the polishing rate of the insulating film is faster than that of the metal film, so that the selectivity can be increased and the effect of reducing dishing can be achieved.

[0043] For the difference in isoelectric point (IEP) before and after the above-mentioned centrifugal separation, it can be measured according to the following formula 3 according to an embodiment.

[0044] [Formula 3]

[0045] The difference in isoelectric point (IEP) before and after centrifugal separation = isoelectric point (IEP) after centrifugal separation - isoelectric point (IEP) before centrifugal separation;

[0046] The isoelectric point before the above-mentioned centrifugal separation refers to after preparing the polishing slurry composition containing abrasive particles, adjusting the pH to at least 3 (for example, pH 3, 4.5, 10) with nitric acid and KOH, and drawing a graph by measuring the value of ζ potential, so as to derive the pH at which the ζ potential is 0. The above-mentioned ζ potential can be the average result of repeating the measurement 5 times with a ζ potential measuring instrument. For example, the above-mentioned ζ potential measuring instrument can be Litesizer 500 of Anton Paar company.

[0047] The isoelectric point after the above-mentioned centrifugal separation can be derived by measuring according to the following method according to an embodiment.

[0048] After centrifuging the polishing slurry composition containing abrasive particles as described above, removing the supernatant, refilling deionized water (DIW), and dispersing the precipitate by ultrasonication for 1 hour, this method is carried out 5 times in total. Then, after centrifuging the above resultant, adjusting the pH to the same pH as before centrifugation with nitric acid and KOH, and then drawing a graph by measuring the value of ζ potential, so as to derive the pH at which the ζ potential is 0.

[0049] For the abrasive particles according to an embodiment of the present invention, adjusting the difference in isoelectric point before and after centrifugal separation to 1 or less can effectively achieve the modification of the surface of the abrasive particles, improve the polishing performance, and ensure the particle size stability at high temperature, which can characterize the effect of improving defects.

[0050] For the above-mentioned abrasive grains, based on 100% by weight of the abrasive grains obtained by centrifuging the slurry containing the surface-modified abrasive grains, using a nitrogen analyzer (ONH-p of ELTRA Corporation), the nitrogen content contained in the above-mentioned abrasive grains can satisfy 0.00001 to 0.5% by weight, or 0.00004 to 0.4% by weight. When the nitrogen content contained in the above-mentioned abrasive grains satisfies the above range, the grinding performance is excellent, and the particle size stability at high temperatures is excellent, so no defects will occur.

[0051] The above nitrogen analyzer is not particularly limited, but for example, it can be ONH-p of ELTRA Corporation.

[0052] For the surface modification target for providing the above-mentioned surface-modified abrasive grains, colloidal silica, fumed silica, alumina, ceria, titania, zirconia, etc. can be used alone or in combination, but specifically, it can be colloidal silica or fumed silica.

[0053] For the above-mentioned abrasive grains, for example, the BET value can be less than 175 m 2 / g. Specifically, the BET value can be 20 to 170 m 2 / g, 20 to 150 m 2 / g, 55 to 170 m 2 / g, or 55 to 100 m 2 / g. If the BET value of the above-mentioned abrasive grains is 175 m 2 / g or more, then at room temperature, the pH and particle size increase, and the storage stability decreases, and problems such as inconsistent grinding speed may occur.

[0054] As a specific example, the above BET value can be the BET value of the abrasive grains before surface modification or the BET value of the surface-modified abrasive grains.

[0055] For example, the above-mentioned modifier may be one or more organosilanes selected from the group consisting of 3-aminopropyltriethoxysilane (APTES), 3-aminopropyltrimethoxysilane (APTMS), N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, and N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride. Specifically, the above-mentioned modifier may be APTES or APTMS. When using the above-mentioned modifier, it is easy to modify the abrasive particles and it is also economically advantageous.

[0056] As a preferred example, the above-mentioned abrasive particles may be silica surface-modified with APTES.

[0057] According to an embodiment of the present invention, a polishing slurry composition containing the above-mentioned abrasive particles satisfying Formula 1 and a solvent can be provided.

[0058] Relative to the total weight of the polishing slurry composition, the above-mentioned abrasive particles may be contained in an amount of 0.01 to 30% by weight, 0.5 to 25% by weight, or 1 to 20% by weight. When the abrasive particles are used within the above content range, the insulation film polishing rate: metal film polishing rate can satisfy 1:1 or more.

[0059] The above-mentioned solvent may contain water, and as the balance, it may be included in the polishing slurry composition other than the abrasive particles. In addition, when the polishing slurry composition further contains a stabilizer, an oxidizing agent, a pH adjuster, etc. described later, in addition to these components, as the balance component, a solvent may be included. For example, the above-mentioned water may be deionized water.

[0060] The above-mentioned polishing slurry composition may further contain an organic acid. By containing the organic acid, the electric double layer on the surface of the modified abrasive particles can be stabilized, so that the storage stability under acidic conditions is more excellent.

[0061] Relative to the total weight of the polishing slurry composition, the above-mentioned organic acid may be contained in an amount of 0.005 to 0.5% by weight, 0.1 to 1% by weight. By stabilizing the electric double layer on the surface of the modified abrasive particles within this range, it has the effect of improving the storage stability under acidic conditions.

[0062] The above-mentioned organic acid may be one or more selected from the group consisting of formic acid (HCOOH), acetic acid (CH3COOH), propionic acid (CH3CH2COOH), oxalic acid, citric acid, malic acid (HO2CCH2CH(OH)CO2H), malonic acid (CH2(COOH)2), sulfonic acid, and tartaric acid (HOOCCH(OH)CH(OH)COOH).

[0063] The above-mentioned polishing slurry composition may further contain an oxidizing agent.

[0064] The above-mentioned oxidizing agent is used to promote the polishing of copper films or tungsten films by rapidly converting metal films into metal oxide films. General oxidizing agents for chemical mechanical polishing slurry compositions can be used, and there are no particular limitations thereto. For example, the above-mentioned oxidizing agent may be an inorganic or organic per-compound. The above-mentioned per-compound refers to a compound containing one or more peroxy groups (-O-O-) or a compound containing an element in its highest oxidation state. As a specific example, the above-mentioned oxidizing agent may be used alone or in combination with hydrogen peroxide, urea hydrogen peroxide, monopersulfate, dipersulfate, peracetic acid, percarbonate, benzoyl peroxide, periodic acid, periodate, perbromic acid, perboric acid, perborate, perchloric acid, perchlorate, permanganic acid, permanganate, etc.

[0065] Relative to the total weight of the polishing slurry composition, the above-mentioned oxidizing agent may be 0.01 to 5% by weight.

[0066] For the above-mentioned polishing slurry composition, the ζ potential may be 3 to 50 mV, 5 to 48 mV, 7 to 48 mV, or 10 to 48 mV. Within this range, the insulating film polishing rate: metal film polishing rate may be 1:1 or more.

[0067] The above-mentioned polishing slurry composition may further contain one or more selected from the group consisting of a catalyst, a biocide, a pH regulator, a corrosion inhibitor, a defect improver, and a pad protector.

[0068] The above-mentioned catalyst may use iron nitrate, iron chloride, iron sulfate, ferrosilicon, etc. Relative to the total weight of the polishing slurry composition, the content of the above-mentioned catalyst may be 0.00002 to 0.07% by weight.

[0069] The above-mentioned biocide is used to prevent the slurry composition for CMP polishing from being contaminated by microorganisms such as bacteria and molds, and its type is not greatly limited.

[0070] Specifically, the above-mentioned antimicrobial agent (fungicide) can use isothiazolinone or its derivatives. For example, methylisothiazolinone (MIT, MI), chloromethyl isothiazolinone (CMIT, CMI, MCI), benzisothiazolinone (BIT), octylisothiazolinone (OIT, OI), dichlorooctylisothiazolinone (DCOIT, DCOI), butylbenzisothiazolinone (BBIT), etc. can be used.

[0071] Relative to the total weight of the abrasive slurry composition, the content of the above-mentioned antimicrobial agent can be 0.0001 to 0.1% by weight. Within the content range of the above-mentioned antimicrobial agent, it has a microbial inhibition effect and excellent dispersibility of the slurry composition.

[0072] The above pH regulator can be one or more selected from the group consisting of nitric acid, hydrochloric acid, phosphoric acid, malonic acid, quaternary ammonium compounds, and potassium hydroxide.

[0073] Relative to the total weight of the abrasive slurry composition, the content of the above pH regulator can be 0.0001 to 1% by weight. By using the above pH regulator, the pH of the abrasive slurry composition can be adjusted to 2 to 5.

[0074] The above corrosion inhibitor can use general substances for preventing the corrosion of metal films. For example, the above corrosion inhibitor can use 1,2,4-triazole, 1H-benzotriazole, etc., and its types are not limited. Relative to the total weight of the abrasive slurry composition, the content of the above corrosion inhibitor can be 0.01 to 5% by weight or 0.001 to 1% by weight.

[0075] The above defect improver can use lysine, picolinic acid, etc. Relative to the total weight of the abrasive slurry composition, the content of the above defect improver can be 0.01 to 5% by weight or 0.001 to 1% by weight.

[0076] The above pad protector can be one or more selected from the group consisting of polysaccharide, cellulose, sucrose, and xylitol.

[0077] The content of the above-mentioned pad protector may be 0.0001 to 1% by weight based on the total weight of the polishing slurry composition.

[0078] The polishing slurry composition according to the present invention contains the above-mentioned polishing particles satisfying Formula 1, and is used for polishing insulating films (such as SiO2, organic films, etc.) and metal films (such as Cu, W, etc.), thereby improving the polishing selectivity, showing high-temperature stability, and also improving the storage stability.

[0079] Specifically, for the above-mentioned polishing slurry composition, the polishing rate of the copper film is / min or less, and the polishing rate of the silicon oxide film is / min or more, and it can be used in the TSV (through silicon via) method. In addition, for the above-mentioned polishing slurry composition, the polishing rate of the copper film: the polishing rate of the insulating film may be 1:1 or more, 1:1.5 or more, 1:3 or more, 1:1 to 1:11, or 1:1.1 to 1:10. For example, for the above-mentioned polishing composition, the polishing selectivity of the silicon oxide film to the copper film may be 1:1 or more, 1:1.5 or more, 1:3 or more, or 1:1 to 1:11, or 1:1.1 to 1:10.

[0080] Advantages of the Invention

[0081] According to the present invention, polishing particles can be provided, in which the carbon content in the polishing particles obtained by centrifuging the polishing slurry composition satisfies a specific value relative to the content of the polishing particles.

[0082] In addition, the present invention can provide polishing particles, and when the surface of the polishing particles is modified, the difference in IEP of the polishing particles before and after centrifugation is adjusted to a specific range, so as to effectively carry out the modification reaction.

[0083] In addition, the polishing slurry composition containing the above-mentioned polishing particles can improve the polishing performance of insulating films and metal films, and especially has high-temperature stability at 50°C or higher.

[0084] In addition, the above-mentioned polishing slurry composition is effectively used in the TSV (through silicon via) method, and can greatly improve the polishing performance. Detailed Embodiments

[0085] Examples are given below to help understand the present invention. However, the following examples are only for illustrating the present invention, and the present invention is not limited to the following examples.

[0086] <Examples, Comparative Examples and Reference Examples>

[0087] <Experimental Conditions and Measuring Equipment>

[0088] The polishing slurry compositions of the examples, comparative examples, and reference examples were subjected to CMP (Chemical Mechanical Polishing) and evaluated under the following conditions.

[0089] 1. Experimental wafers: 10-inch blanket wafers of insulating film (PE-TEOS), 10-inch blanket wafers of metal film (Cu), and 10-inch wafers with copper patterns (product name SKW 6-3).

[0090] 2. Polisher: AP300 (CST Corporation)

[0091] 3. Polishing conditions

[0092] [Table 1]

[0093]

[0094] 4. Pad: IC-1010 (DuPont Corporation)

[0095] 5. Thickness (polishing rate) measurement equipment

[0096] - Metal film: CMT-SR5000 (AIT Corporation)

[0097] - Insulating film: ST-5000 (K-MAC Corporation)

[0098] - Polishing rate = thickness before polishing – thickness after polishing

[0099] 6. Particle size and zeta-potential analysis equipment

[0100] - Litesizer (Anton Paar Corporation)

[0101] 7. Defect analysis

[0102] - Surfscan SP2 (KLA-Tencor Corporation)

[0103] 8. Carbon content analysis

[0104] - Test instrument: ELEMENTRAC CS-d (ELTRA Corporation)

[0105] - Detector: IR Cell

[0106] a. Method for measuring carbon content after centrifugation

[0107] After pretreating the sample for carbon content analysis using the following method, the carbon content after centrifugation was measured.

[0108] ① After centrifuging the grinding slurry at 4 °C, 20,000 rpm for 10 min (the first time was carried out under the condition of 30 min), the supernatant was removed and DIW was refilled.

[0109] ② The precipitate was dispersed by ultrasonication for 1 hour and this was carried out 5 times in total according to the above method.

[0110] ③ The precipitated particles were dried, recovered in powder form, and carbon quantitative analysis was carried out using a carbon analyzer (ELEMENTRAC CS-d of ELTRA Corporation).

[0111] 9. Centrifugation conditions and measurement methods for samples before and after centrifugation for determining the difference in isoelectric point (IEP)

[0112] a. Sample before centrifugation

[0113] ① The pH of the grinding slurry was adjusted to pH 3, 4.5, and 10 respectively using nitric acid and KOH.

[0114] ② The ζ potential of the sample with the adjusted pH was measured.

[0115] b. Sample after centrifugation

[0116] ① After centrifuging the grinding slurry at 4 °C, 20,000 rpm for 10 min (the first time was carried out under the condition of 30 min), the supernatant was removed and deionized water (DIW) was refilled.

[0117] ② Then, the precipitate was dispersed by ultrasonication for 1 hour and this was carried out 5 times in total according to the above method.

[0118] ③ After the final centrifugation, the pH was adjusted to pH 3, 4.5, and 10 respectively using nitric acid and KOH to make the pH the same as before centrifugation.

[0119] ④ The ζ potential of the sample with the adjusted pH was measured.

[0120] c. Difference in isoelectric point (IEP) before and after centrifugation (IEP change value)

[0121] For the difference in isoelectric point (IEP) before and after the above centrifugation, it can be measured according to the following formula 3.

[0122] [Formula 3]

[0123] Difference in isoelectric point (IEP) before and after centrifugal separation = IEP after centrifugal separation – IEP before centrifugal separation;

[0124] <Preparation of Polishing Slurry 1: Examples 1 to 5 and Comparative Examples 1 to 2>

[0125] In order to use silica surface-modified with organosilane in the polishing slurry, the silica was modified according to BET as shown in Table 2 below.

[0126] Silica, APTES (surface modifier), and acetic acid were mixed in the amounts shown in Table 2 below in distilled water and stirred with a mechanical stirrer for a certain period of time to prepare a polishing slurry. In addition, the pH was adjusted to 3 with a pH regulator.

[0127] <Experimental Example 1>

[0128] The pH and particle size stability were evaluated according to the BET of silica particles.

[0129] For Examples 1 to 5 and Comparative Examples 1 and 2 above, the pH and particle size stability were evaluated according to the BET of silica particles, and the results are shown in Table 2.

[0130] The pH and particle size stability were compared according to the BET of silica at room temperature (23°C), and the results are shown in Table 2. The silica wt% in Table 2 below is the weight percentage of silica calculated based on the total weight percentage of the polishing slurry composition.

[0131] In addition, the values of the following Formulas 1 and 2 were measured for the polished particles after centrifugal separation according to the carbon content measurement method after centrifugal separation in 8. above, and the results are shown in Table 2.

[0132] Specifically, the ratio of the carbon content after centrifugal separation to the polished particle content was calculated according to the following Formula 1.

[0133] [Formula 1]

[0134] (Carbon content after centrifugal separation / Polished particle content) × 10000;

[0135] In the above Formula 1, the carbon content after centrifugal separation is the carbon content on the surface of the polished particles measured using a carbon analyzer based on the total weight of the polished particle solids obtained after centrifuging the slurry containing surface-modified polished particles for 10 minutes, and the polished particle content is the content of the surface-modified polished particles contained in the slurry.

[0136] In addition, the ratio of the modifier content to the polished particle content was calculated according to the following Formula 2a.

[0137] [Formula 2a]

[0138] (Modifier content / Abrasive particle content) × 10000;

[0139] In the above Formula 2a, the above modifier content is the content of the modifier added when preparing the surface-modified abrasive particles, and the above abrasive particle content is the content of the surface-modified abrasive particles contained in the above slurry.

[0140] In addition, the difference in the isoelectric point before and after centrifugation of the abrasive particles (hereinafter referred to as the IEP difference) was measured according to the centrifugation conditions and measurement methods of the samples before and after centrifugation in the above item 9., and the results are shown in Table 2.

[0141] [Table 2]

[0142]

[0143] According to Table 2 above, compared with Reference Examples 1 and 2 with a BET value of 175 m 2 / g, the BET value of silica in Examples 1 to 5 is less than 175 m 2 / g, and the pH and the particle size of the abrasive particles did not change after one day at room temperature (23 °C), indicating better storage stability.

[0144] <Preparation of Polishing Slurry 2: Examples 6 to 12 and Comparative Examples 1 to 6>

[0145] Silica, APTES, and acetic acid were mixed in the amounts shown in Table 3 below in distilled water (the balance), and stirred with a mechanical stirrer for a certain period of time to prepare a polishing slurry. At this time, Comparative Examples 1 to 5 and Examples 6 to 12 were stirred for 24 hours, and Comparative Example 6 was stirred for 5 minutes. In addition, the pH was adjusted to 3.5 with a pH regulator.

[0146] Next, before polishing the polishing pad, a polishing slurry composition was prepared by mixing hydrogen peroxide.

[0147] [Table 3]

[0148]

[0149] <Experimental Example 2>

[0150] For the above Examples 6 to 12 and Comparative Examples 1 to 6, CMP (Chemical Mechanical Polishing) was evaluated by the above method, and the results are shown in Table 4.

[0151] [Table 4]

[0152]

[0153]

[0154] Note: When the change value of IEP before and after centrifugal separation is 1 or more, it indicates that the surface of silica is slightly modified or the modifier that is not modified on the silica surface is included in the supernatant and removed by centrifugal separation.

[0155] According to Table 4 above, in Examples 6 to 12, the values satisfying Formula 1 are from 2 to 285. For Comparative Examples 1, 2, 5, and 6 where the value of Formula 1 is less than 2, due to the slow polishing rate of the insulating film (SiO2), not only can the selectivity between the insulating film (SiO2) and the metal film (Cu) expected in the present invention not be satisfied, but also adverse results such as an increase in ditching and a large number of defects in the insulating film (SiO2) occur. In addition, in Comparative Examples 3 and 4 where the value of Formula 1 is greater than 285, there is also a large increase in the defects of the insulating film.

[0156] Furthermore, in Examples 6 to 12, the values satisfying Formula 2 are from 10 to 1240. Since the values within the range of the above-mentioned Formula 2 are satisfied, both ditching and the defects of the insulating film are reduced.

[0157] <Polishing Slurry Preparation 3: Examples 13 to 15 and Comparative Examples 7 to 9>

[0158] Mix silica (BET 80m 2 / g), APTES, and acetic acid in the amounts shown in Table 5 below in distilled water, and stir with a mechanical stirrer for a certain time to prepare a polishing slurry. In addition, adjust the pH to 3.5 with a pH regulator.

[0159] <Experimental Example 3>

[0160] Evaluate the particle size stability at 50°C

[0161] For the above Examples 13 to 15 and Comparative Examples 7 to 9, evaluate CMP (Chemical Mechanical Polishing) using the above method, and the results are shown in Table 5.

[0162] In addition, compare the particle size stability at 50°C for 4 weeks, and the results are shown in Table 5.

[0163] [Table 5]

[0164]

[0165] The purpose of evaluating the particle size stability at 50°C is to confirm whether the particles agglomerate at the temperature (40 to 60°C) generated by the friction between the pad and the wafer during polishing, which is one of the reasons for defects.

[0166] According to Table 5 above, when Examples 13 to 15 satisfy Formula 1 and Formula 2, compared with Comparative Examples 7 to 9 that do not satisfy Formula 1 and Formula 2, the particle size stability is maintained for 4 weeks at a high temperature of 50 °C or higher. In addition, such an effect can support the result of the reduction in defects in Table 4 above.

Claims

1. A polishing particle, wherein, the polishing particle satisfies the following formula 1, [Formula 1] (Carbon content after centrifugation / Polishing particle content) × 10000 = 2 to 285; In formula 1, the carbon content after centrifugation is the carbon content of the polishing particles measured using a carbon analyzer based on 100% by weight of the polishing particle solids obtained by centrifuging the slurry containing the surface-modified polishing particles.

2. The polishing particle according to claim 1, wherein, the surface of the polishing particle is modified by a modifier.

3. The polishing particle according to claim 2, wherein, the polishing particle satisfies the following formula 2: [Formula 2] (Modifier content / Polishing particle content) × 10000 = 10 to 1240.

4. The polishing particle according to claim 1, wherein, the difference in isoelectric point before and after centrifugation is 1 or less.

5. The polishing particle according to claim 1, wherein, The BET value is less than 175 m 2 / g.

6. The polishing particle according to claim 5, wherein, The BET value is 20 to 170 m 2 / g.

7. The polishing particle according to claim 2, wherein, the modifier is one or more organosilanes selected from the group consisting of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butyl)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, and N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride.

8. The polishing particle according to claim 1, wherein, the nitrogen content contained in the polishing particle measured using a nitrogen analyzer based on 100% by weight of the polishing particle solids obtained by centrifuging the slurry containing the surface-modified polishing particles is 0.00001 to 0.5% by weight.

9. A polishing slurry composition comprising the polishing particle according to claim 1 and a solvent.

10. The polishing slurry composition according to claim 9, wherein, the polishing particle comprises 0.01 to 30% by weight relative to the total weight of the polishing slurry composition.

11. The polishing slurry composition according to claim 9, wherein, the ζ potential is 3 to 50 mV.

12. The polishing slurry composition according to claim 9, wherein, the polishing slurry composition further comprises an organic acid.

13. The polishing slurry composition according to claim 9, wherein, the polishing slurry composition further comprises an oxidizing agent.

14. The polishing slurry composition according to claim 9, wherein, the polishing slurry composition further comprises one or more selected from the group consisting of a catalyst, an antimicrobial agent, a pH regulator, a corrosion inhibitor, a defect improver, and a pad protector.

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