Abrasive particles and abrasive slurry composition using the same

Abstract

In the present invention, the ratio of modifier content / silica content during surface modification of abrasive particles, the ratio of carbon content / silica content of the modifier in the slurry after centrifugation, or the difference in isoelectric point (IEP) of the modified abrasive particles in the slurry before and after centrifugation are adjusted to specific ranges, thereby improving the polishing performance of insulating films and metal films and providing surface-modified abrasive particles with high temperature stability, and a polishing slurry composition containing the same.

Description

[Technical Field]

[0001] The present invention relates to abrasive particles suitable for polishing metal barriers in through-silicon vias (TSVs) and a polishing slurry composition using the same. [Background technology]

[0002] In the semiconductor manufacturing process, a single chip that uses integrated circuit technology contains millions of functional elements, such as transistors, capacitors, and resistors, and these individual elements are connected to each other by wires that are patterned into a specific shape to form a circuit. Integrated circuits have become smaller with each generation, and as a result, the functionality of a single chip has gradually increased.

[0003] However, there is a limit to simply reducing the size of elements, so recently active research has been conducted on multi-layer wiring structures in which each element is formed in multiple layers. A typical method is the through silicon via (TSV) method, in which silicon wafers are stacked, holes are drilled, and then the holes are filled with metal such as copper to form through electrodes.

[0004] The TSV method is a type of packaging technology that can shorten the connection length between semiconductor packages and is gradually being used for high-performance, ultra-small semiconductors. However, the TSV method has various technical difficulties, the most notable of which is that the process of chemical-mechanical polishing of the packed metal takes much longer than the existing chemical-mechanical polishing process.

[0005] To solve the above-mentioned problems, it is necessary to develop a chemical-mechanical polishing slurry composition that can improve the polishing rate and selectivity of the polishing slurry for copper and tungsten films and polish metal films at high speed.

[0006] However, no slurries commercially available or developed to date have yet fully satisfied all of these requirements. Summary of the Invention [Problem to be solved by the invention]

[0007] The present specification provides abrasive particles that have improved polishing performance for insulating films and metal films and high temperature stability.

[0008] The present invention also provides a polishing slurry composition containing the abrasive particles, which has improved high-temperature stability and can be easily stored for a long period of time without being affected by the temperature of the surrounding environment. [Means for solving the problem]

[0009] The present specification provides abrasive particles that satisfy the following formula 1: [Formula 1] (Carbon content after centrifugation / Abrasive particle content) x 10,000 = 2~285

[0010] In the above formula 1, the carbon content after centrifugation is the content of carbon 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 a slurry containing surface-modified abrasive particles for 10 minutes, and the abrasive particle content is the content of surface-modified abrasive particles contained in the slurry.

[0011] The present specification also provides an abrasive slurry composition containing the abrasive particles and a solvent.

[0012] The present invention will be described in more detail below. The terms and phrases used in the specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a way that is consistent with the technical concept of the present invention, based on the principle that the inventor can appropriately define the concept of the term in order to best describe his / her invention.

[0013] Additionally, the meaning of "comprise" as used herein embodies certain properties, regions, integers, steps, operations, elements and / or components, and does not exclude the presence or addition of other properties, regions, integers, steps, operations, elements and / or components.

[0014] Hereinafter, the abrasive particles according to one embodiment of the present invention and the abrasive slurry composition containing the same will be described in more detail.

[0015] The present invention provides surface-modified abrasive particles and a polishing slurry composition containing the same, which have improved polishing performance for insulating films and metal films and high-temperature stability, by modifying the surfaces of the abrasive particles, centrifuging the particles, and then adjusting the ratio of the carbon content of the abrasive particles to the abrasive particle content within a specific range.

[0016] The abrasive particles according to the present invention are not particularly limited, but may include, for example, silica, ceria, alumina, zirconia, etc. The abrasive particles may be surface-modified abrasive particles, specifically, abrasive particles surface-modified with a modifier. When surface-modified abrasive particles are used in the present invention, the polishing rate of the insulating film relative to the metal film can be improved, and the selectivity between the metal film and the insulating film can be increased while reducing dishing.

[0017] According to one embodiment of the present invention, abrasive particles that satisfy the following formula 1 can be provided. [Formula 1] (Carbon content after centrifugation / Abrasive particle content) x 10,000 = 2~285

[0018] In the above formula 1, the carbon content after centrifugation is the content of carbon 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 a slurry containing surface-modified abrasive particles for 10 minutes, and the abrasive particle content is the content of surface-modified abrasive particles contained in the slurry.

[0019] The carbon analyzer may be, for example, an ELEMENTRAC CS-d from ELTRA.

[0020] The value of the formula 1 may be, for example, 2 to 285, 5 to 280, 15 to 280, 5 to 200, 10 to 150, or 200 to 285. If the value of the formula 1 is less than 2, the content of the modifier is low compared to the abrasive particles, resulting in insufficient improvement in polishing performance. If the value exceeds 285, the particle size stability at high temperatures decreases, resulting in an increase in defects.

[0021] In the above formula 1, the carbon content of the abrasive particles after centrifugation may be the carbon content in the abrasive particles measured by centrifuging the abrasive slurry composition containing the surface-modified abrasive particles, removing the supernatant, refilling with deionized water (DIW), and dispersing the precipitate using ultrasonic treatment for 1 hour 5 to 10 times, drying the precipitated particles, recovering them in a powder state, and measuring the carbon content in the abrasive particles using a carbon analyzer (ELTRA ELEMENTRAC CS-d).

[0022] More specifically, the carbon content after centrifugation may be the carbon content contained on the surface, i.e., the carbon content (wt%) of the surface modifier bonded to the abrasive particle, based on the total weight (100 wt%) of the solid content of the abrasive particle obtained by centrifugation after surface modification.

[0023] The centrifugation can be carried out, for example, under conditions of 4° C., 20,000 rpm, and 10 to 30 minutes, and the first centrifugation can be carried out under conditions of 30 minutes.

[0024] According to another embodiment of the present invention, the abrasive particles may satisfy the following formula 2: [Formula 2] (Modifier content / Abrasive particle content) x 10,000 = 10~1,240

[0025] In the above formula 2, the modifier content is, for example, the content of the modifier added during the production of the surface-modified abrasive particles, or the content of the modifier present on the surface of the abrasive particles after surface modification, and the abrasive particle content may be the content of the surface-modified abrasive particles contained in a slurry containing the surface-modified abrasive particles. The content of the modifier present on the surface of the abrasive particles after surface modification may be the content of the modifier measured based on 100% by weight of the solid content of the abrasive particles obtained after centrifuging the slurry containing the surface-modified abrasive particles.

[0026] In this regard, in the present invention, the content of the modifier present on the surface of the abrasive particle after the surface modification may refer to the content of carbon bonded to the surface of the abrasive particle, which is obtained by centrifuging a slurry containing the surface-modified abrasive particle for 10 minutes and then drying the abrasive particle. Therefore, the content of the modifier may include the carbon content after centrifugation according to Equation 1. The carbon content may be measured using a carbon analyzer.

[0027] In the above formula 2, the abrasive particles may be surface-modified abrasive particles with a modifier. Therefore, the content of the abrasive particles is the content of the surface-modified abrasive particles contained in the slurry containing the surface-modified abrasive particles, as in formula 1.

[0028] In the present invention, the abrasive particle solid content obtained after the centrifugation may be a dry solid content, and the drying temperature is not limited. For example, the abrasive particle solid content may be dried at a temperature of about 30 to 60°C.

[0029] The value of the above formula 2 may be 10 to 1,240, 20 to 1,218, 64 to 1,218, 20 to 870, 45 to 650, or 500 to 1,240. Within the value range of the above formula 2, the polishing performance is excellent, and the particle size stability is excellent at high temperatures, so that defects do not occur.

[0030] The content of the modifier may be, for example, 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, relative to 100 parts by weight of the abrasive particles.

[0031] When the content of the modifier is within the above range, the abrasive particles are sufficiently modified to have high abrasive performance, and the particle size stability at high temperatures does not decrease.

[0032] According to yet another embodiment of the present invention, the difference in isoelectric point (IEP) of the abrasive particles before and after centrifugation may be 1 or less, or 0.1 to 1 or less, or 0.1 to 0.8.

[0033] A change in IEP value of 1 or more before and after centrifugation means that the surface of the abrasive particles was not modified or was only weakly modified, which means that the modifier that was not used to modify the surface of the abrasive particles was removed by centrifugation and contained in the supernatant.

[0034] The abrasive particles of the present invention have improved particle dispersibility compared to conventional abrasive particles, and can exhibit the effects of increasing the selectivity and reducing dishing by making the polishing rate of insulating films faster than that of metal films.

[0035] In one embodiment, the difference in isoelectric point (IEP) before and after centrifugation can be measured by the following equation 3: [Formula 3] Difference in isoelectric point (IEP) before and after centrifugation = IEP after centrifugation - IEP before centrifugation

[0036] The isoelectric point before centrifugation means that a polishing slurry composition containing abrasive particles is prepared, and then the pH is adjusted to a minimum of 3 (e.g., pH 3, 4.5, 10) with nitric acid and KOH, and the zeta potential is measured. A graph is then plotted to determine the pH at which the zeta potential becomes 0. The zeta potential may be the average value of five repeated measurements using a zeta potential meter, and the zeta potential meter may be, for example, an Anton Paar Litesizer 500.

[0037] According to one embodiment, the isoelectric point after centrifugation can be measured and derived by the following method.

[0038] The polishing slurry composition containing the abrasive particles is centrifuged, the supernatant is removed, and the mixture is refilled with deionized water (DIW), followed by ultrasonication to disperse the precipitate for one hour, a total of five times.The resultant is then centrifuged, and the pH is adjusted to the same pH as before centrifugation using nitric acid and KOH.The zeta potential is then measured and plotted on a graph to determine the pH at which the zeta potential becomes zero.

[0039] In one embodiment of the abrasive particles of the present invention, the difference in isoelectric point before and after centrifugation is adjusted to 1 or less, thereby effectively modifying the surface of the abrasive particles, improving polishing performance, and ensuring particle size stability at high temperatures, thereby achieving the effect of improving defects.

[0040] The abrasive particles may have a nitrogen content of 0.00001 to 0.5 wt % or 0.00004 to 0.4 wt % as determined by a nitrogen analyzer (ELTRA ONH-p) based on 100 wt % of the abrasive particles obtained after centrifuging a slurry containing the surface-modified abrasive particles. When the nitrogen content of the abrasive particles satisfies this range, the abrasive particles have excellent polishing performance and excellent particle size stability at high temperatures, preventing defects.

[0041] The nitrogen analyzer is not particularly limited, but may be, for example, an ONH-p from ELTRA.

[0042] The surface modification target to provide the surface-modified abrasive particles may be colloidal silica, fumed silica, alumina, ceria, titania, zirconia, or the like, either alone or in combination. Specifically, the surface modification target may be colloidal silica or fumed silica.

[0043] The abrasive particles have a BET value of, for example, 175 m 2 / g, specifically, a BET value of 20 to 170 m 2 / g, 20-150m 2 / g, 55-170m 2 / g, or 55-100m 2 The abrasive particles may have a BET value of 175m / g. 2 If the pH is more than 1 / g, the pH and particle size will increase at room temperature, which may result in a decrease in storage stability and an inconsistent polishing rate.

[0044] As a specific example, the BET value may be the BET value of the abrasive particles before surface modification, or the BET value of the abrasive particles after surface modification.

[0045] Examples of the modifier include 3-aminopropyltriethoxysilane (APTES), 3-aminopropyltrimethoxysilane (APTMS), N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxy ... The modifier may be one or more organic silanes selected from the group consisting of 3-aminopropyltrimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, and n-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride. Specifically, the modifier may be APTES or APTMS. Use of such modifiers facilitates modification of the abrasive particles and is economically advantageous.

[0046] As a preferred example, the abrasive particles may be silica surface-modified with APTES. According to one embodiment of the present invention, there is provided an abrasive slurry composition including abrasive particles satisfying the above formula 1 and a solvent.

[0047] The abrasive particles may be contained in an amount of 0.01 to 30 wt %, 0.5 to 25 wt %, or 1 to 20 wt % based on the total weight of the polishing slurry composition. When the abrasive particles are used within this content range, the polishing rate for insulating film:polishing rate for metal film can be 1:1 or more.

[0048] The solvent may include water, and may be included as the remaining amount in the polishing slurry composition excluding the abrasive particles. In addition, when the polishing slurry composition further includes a stabilizer, an oxidizing agent, a pH adjuster, etc., which will be described later, the solvent may be included as the remaining component excluding these components. For example, the water may be deionized water.

[0049] The polishing slurry composition may further include an organic acid. By including the organic acid, the electric double layer on the surface of the modified abrasive particles can be stabilized, thereby providing better storage stability in acidic conditions.

[0050] The organic acid may be contained in an amount of 0.005 to 0.5 wt % or 0.1 to 1 wt % based on the total weight of the polishing slurry composition, and within this range, it has the effect of stabilizing the electric double layer on the surface of the modified abrasive particles and improving storage stability in acidic conditions.

[0051] The 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). The polishing slurry composition may further include an oxidizing agent.

[0052] The oxidizing agent is used to rapidly convert a metal layer into a metal oxide layer, facilitating the polishing of a copper or tungsten layer. Conventional oxidizing agents used in chemical-mechanical polishing slurry compositions can be used without any particular limitation. For example, the oxidizing agent can be an inorganic or organic per-compound. The per-compound refers to a compound containing one or more peroxy groups (—OO—) or a compound containing an element in its highest oxidation state. Specific examples of the oxidizing agent include hydrogen peroxide, urea hydrogen peroxide, monopersulfate, dipersulfate, peracetic acid, percarbonate, benzoyl peroxide, periodic acid, periodic acid salts, perbromic acid, perboric acid, perboric acid salts, perchloroic acid and perchloroic acid salts, permanganate, and permanganate salts, which can be used alone or in combination.

[0053] The oxidizing agent may be present in an amount of 0.01 to 5% by weight based on the total weight of the polishing slurry composition.

[0054] The polishing slurry composition may have a zeta potential of 3 to 50 mV, 5 to 48 mV, 7 to 48 mV, or 10 to 48 mV, and within this range, the polishing rate for the insulating film:polishing rate for the metal film may be 1:1 or more.

[0055] The polishing slurry composition may further include at least one selected from the group consisting of a catalyst, a biocide, a pH adjuster, a corrosion inhibitor, a defect improving agent, and a pad protecting agent.

[0056] The catalyst may be iron nitrate, iron chloride, iron sulfate, ferrosilicon, etc. The content of the catalyst may be 0.00002 to 0.07% by weight based on the total weight of the polishing slurry composition.

[0057] The biocide prevents the CMP polishing slurry composition from being contaminated by microorganisms such as bacteria and fungi, and the type of biocide is not particularly limited.

[0058] Specifically, the biocide (bactericide) may be isothiazolinone or a derivative thereof, such as methylisothiazolinone (MIT, MI), chloromethylisothiazolinone (CMIT, CMI, MCI), benzisothiazolinone (BIT), octylisothiazolinone (OIT, OI), dichlorooctylisothiazolinone (DCOIT, DCOI), or butylbenzisothiazolinone (BBIT).

[0059] The content of the biocide may be 0.0001 to 0.1 wt % based on the total weight of the polishing slurry composition. Within this range of biocide content, the slurry composition has excellent dispersibility while still having a microbial inhibitory effect.

[0060] The pH adjuster may be one or more selected from the group consisting of nitric acid, hydrochloric acid, phosphoric acid, malonic acid, a quaternary ammonium compound, and potassium hydroxide.

[0061] The content of the pH adjuster may be 0.0001 to 1 wt % based on the total weight of the polishing slurry composition. By using the pH adjuster, the polishing slurry composition can be adjusted to a pH of 2 to 5.

[0062] The corrosion inhibitor may be a conventional substance for preventing corrosion of metal films. For example, the corrosion inhibitor may be 1,2,4-triazole, 1H-benzotriazole, etc., and the type is not limited. The content of the corrosion inhibitor may be 0.01 to 5 wt % or 0.001 to 1 wt % based on the total weight of the polishing slurry composition.

[0063] The defect improving agent may be lysine, picolinic acid, etc., and its content may be 0.01 to 5 wt % or 0.001 to 1 wt % based on the total weight of the polishing slurry composition.

[0064] The pad protectant may be one or more selected from the group consisting of polysaccharide, cellulose, sucrose, and xylitol.

[0065] The content of the pad protective agent may be 0.0001 to 1% by weight based on the total weight of the polishing slurry composition.

[0066] The polishing slurry composition of the present invention contains abrasive particles that satisfy the above formula 1, and can be used to polish insulating films (SiO2, organic films, etc.) and metal films (Cu, W, etc.), thereby improving the polishing selectivity, exhibiting high temperature stability, and improving storage stability.

[0067] Specifically, the polishing slurry composition has a copper film polishing rate of 1800 Å / min or less and a silicon oxide film polishing rate of 1400 Å / min or more, and can be used in a TSV (through silicon via) method. The polishing slurry composition may have a ratio of insulating film polishing rate to metal film polishing rate of 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, the polishing composition may have a copper film polishing selectivity to silicon oxide film of 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. [Effects of the Invention]

[0068] According to the present invention, it is possible to provide abrasive particles in which the carbon content in the abrasive particles obtained after centrifuging the abrasive slurry composition satisfies a specific value relative to the abrasive particle content.

[0069] In addition, the present invention can provide abrasive particles in which the modification reaction is effectively carried out by adjusting the difference in IEP of the abrasive particles before and after centrifugation within a specific range during the surface modification of the abrasive particles.

[0070] Furthermore, a polishing slurry composition containing the abrasive particles can improve the polishing performance of insulating films and metal films, and can have high temperature stability, particularly at 50° C. or higher.

[0071] In addition, the polishing slurry composition can be effectively used in a TSV (through silicon via) method to significantly improve polishing performance. DETAILED DESCRIPTION OF THE INVENTION

[0072] Examples are presented below to aid in understanding the present invention, but the following examples are merely for illustrative purposes and are not intended to limit the present invention. [Example]

[0073] <Examples, Comparative Examples and Reference Examples> <Experimental conditions and measurement equipment> 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.

[0074] 1. Experimental wafer: 10-inch insulating film (PE-TEOS) blanket wafer, 10-inch metal film (Cu) blanket wafer, 10-inch Cu pattern wafer (product name SKW6-3) 2. Polisher: AP300 (CST) 3.Polishing conditions: [Table 1] 4. Polishing pad: IC-1010 (Dupont) 5. Thickness (removal rate) measuring device -Metal film: CMT-SR5000 (AIT) -Insulating film: ST-5000 (K-MAC) - Polishing rate = thickness before polishing - thickness after polishing

[0075] 6. Particle size and zeta potential analyzer -Litesizer (Anton Paar) 7. Defect analysis -Surfscan SP2 (KLA Tenkor) 8. Carbon content analysis -Test equipment: ELEMENTRAC CS-d (ELTRA) -Detector: IR Cell a.Measuring method for carbon content after centrifugation The samples for carbon content analysis were pretreated in the following manner, and then the carbon content was measured after centrifugation. (1) After centrifuging the polishing slurry under the conditions of 4°C, 20,000 rpm, and 10 minutes (the first time was performed for 30 minutes), the supernatant was removed and the mixture was refilled with DIW. (2) The precipitate was dispersed using ultrasonication for 1 hour, and the same procedure was repeated a total of 5 times. (3) The precipitated particles were dried and collected in powder form, and quantitative carbon analysis was carried out using a carbon analyzer (ELTRA ELEMENTRAC CS-d).

[0076] 9. Centrifugation conditions and measurement method for pre- and post-centrifugation samples to measure the difference in isoelectric point (IEP) a. Sample before centrifugation (1) The pH of the polishing slurry was adjusted to 3, 4.5, and 10 using nitric acid and KOH, respectively. (2) The zeta potential of the pH-adjusted sample was measured. b. Sample after centrifugation (1) The polishing slurry was centrifuged at 4°C, 20,000 rpm, and 10 minutes (the first time was 30 minutes), after which the supernatant was removed and the slurry was refilled with deionized water (DIW). (2) Then, the precipitate was dispersed for 1 hour using ultrasonic treatment, and the same procedure was repeated a total of 5 times. (3) Finally, after centrifugation, the pH was adjusted to 3, 4.5, and 10 using nitric acid and KOH, respectively, so that the pH was the same as before centrifugation. (4) The zeta potential of the pH-adjusted sample was measured. c. Difference in isoelectric point (IEP) before and after centrifugation (IEP change value) The difference in isoelectric point (IEP) before and after the centrifugation can be measured by the following equation 3. [Formula 3] Difference in isoelectric point (IEP) before and after centrifugation = IEP after centrifugation - IEP before centrifugation

[0077] <Preparation of Polishing Slurry 1: Examples 1 to 5 and Reference Examples 1 and 2> In order to use silica surface-modified with organic silane in polishing slurries, the silica was modified according to BET as shown in Table 2 below.

[0078] The polishing slurry was prepared by mixing silica, APTES (surface modifier), and acetic acid in the amounts shown in Table 2 below with distilled water and stirring for a certain period of time using a mechanical stirrer. The pH was adjusted to 3 using a pH adjuster.

[0079] <Experimental Example 1> Evaluation of pH and particle size stability of silica particles according to BET The pH and particle size stability of the silica particles according to BET were evaluated for Examples 1 to 5 and Reference Examples 1 and 2, and the results are shown in Table 2.

[0080] The pH and particle size stability of silica at room temperature (23°C) were compared according to BET, and the results are shown in Table 2. In Table 2 below, silica wt% is the weight % of silica calculated based on the total weight % of the polishing slurry composition.

[0081] Furthermore, the values ​​of the following formulas 1 and 2 were measured for the abrasive particles after centrifugation using the method for measuring the carbon content after centrifugation described above in 8. The results are shown in Table 2.

[0082] Specifically, the ratio of carbon content to abrasive particle content after centrifugation was calculated using the following formula 1. [Formula 1] (Carbon content after centrifugation / Abrasive particle content) x 10,000

[0083] In the above formula 1, the carbon content after centrifugation is the content of carbon 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 a slurry containing surface-modified abrasive particles for 10 minutes, and the abrasive particle content is the content of surface-modified abrasive particles contained in the slurry.

[0084] The ratio of modifier content to abrasive particle content was calculated using the following formula 2a. [Formula 2a] (Modifier content / Abrasive particle content) x 10,000

[0085] In the above formula 2a, the modifier content is the content of the modifier added during the production of the surface-modified abrasive particles, and the abrasive particle content is the content of the surface-modified abrasive particles contained in the slurry.

[0086] In addition, the difference in isoelectric point (hereinafter referred to as IEP difference) of the abrasive particles before and after centrifugation was measured using the centrifugation conditions and measurement method for the samples before and after centrifugation described above in 9. Table 2 shows the results. [Table 2]

[0087] According to Table 2, the BET value of silica is 175 m 2 Examples 1 to 5, in which the BET value is less than 175m / g, 2 / g or more, there was no change in pH or particle size of the abrasive particles after 1 day at room temperature (23°C), demonstrating that the storage stability was even better.

[0088] <Preparation of Polishing Slurry 2: Examples 6 to 12 and Comparative Examples 1 to 6> The polishing slurries were prepared by mixing silica, APTES, and acetic acid with distilled water (the remaining amount) in the amounts shown in Table 3 below, and stirring for a certain period of time using a mechanical stirrer. Comparative Examples 1 to 5 and Examples 6 to 12 were stirred for 24 hours, and Comparative Example 6 was stirred for 5 minutes. The pH was adjusted to 3.5 using a pH adjuster.

[0089] Next, before polishing the polishing pad, hydrogen peroxide was mixed to prepare a polishing slurry composition. [Table 3]

[0090] <Experimental Example 2> For Examples 6 to 12 and Comparative Examples 1 to 6, CMP (Chemical Mechanical Polishing) evaluation was carried out by the method described above, and the results are shown in Table 4. [Table 4]

[0091] Note) If the IEP change value before and after centrifugation is 1 or more, it means that the silica surface is weakly modified or that the modifier that has not modified the silica surface is included in the supernatant liquid by centrifugation and is washed away.

[0092] According to Table 4, Examples 6 to 12 satisfy the value of Equation 1 of 2 to 285, whereas Comparative Examples 1, 2, 5, and 6, in which the value of Equation 1 is less than 2, exhibit poor results, such as a slow removal rate of the insulating film (SiO2), not satisfying the selectivity between the insulating film (SiO2) and the metal film (Cu) targeted in the present invention, and also resulting in a significant increase in dishing and defects in the insulating film (SiO2).It was also confirmed that Comparative Examples 3 and 4, in which the value of Equation 1 exceeds 285, also exhibited a significant increase in defects in the insulating film.

[0093] Furthermore, it was confirmed that in Examples 6 to 12, the value of Equation 2 satisfied the range of 10 to 1,240, and by satisfying the value range of Equation 2, it was confirmed that dishing and defects in the insulating film were all reduced.

[0094] <Preparation of Polishing Slurry 3: Examples 13 to 15 and Comparative Examples 7 to 9> Silica (BET80m) was dissolved in distilled water at the content shown in Table 5 below. 2 The polishing slurry was prepared by mixing 100g of sucrose, 100g of sucrose, 100g of APTES, and 100g of acetic acid with a mechanical stirrer for a certain period of time, and adjusting the pH to 3.5 using a pH adjuster.

[0095] <Experimental Example 3> Particle size stability evaluation at 50℃ For Examples 13 to 15 and Comparative Examples 7 to 9, CMP (Chemical Mechanical Polishing) evaluation was carried out by the method described above, and the results are shown in Table 5.

[0096] Furthermore, the particle size stability was compared at 50°C for 4 weeks, and the results are shown in Table 5. [Table 5]

[0097] The purpose of the particle size stability evaluation at 50°C is to check whether particles aggregate at the temperature (40-60°C) generated by friction between the pad and wafer during polishing, which is one of the causes of defects.

[0098] According to Table 5, when Formula 1 and Formula 2 are satisfied as in Examples 13 to 15, particle size stability is maintained at high temperatures of 50°C or higher for 4 weeks compared to Comparative Examples 7 to 9, which do not satisfy Formula 1 and Formula 2. This effect also supports the result of reduced defects in Table 4.

Claims

1. Abrasive particles that satisfy the following formula 1: [Formula 1] (Carbon content after centrifugation / Abrasive particle content) x 10,000 = 2 to 285 In the above formula 1, the carbon content after centrifugation is the carbon content of the abrasive particles measured using a carbon analyzer based on 100% by weight of the solid content of the abrasive particles obtained after centrifuging a slurry containing the surface-modified abrasive particles.

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

3. 3. The abrasive particles according to claim 2, which satisfy the following formula 2: [Formula 2] (modifier content / abrasive particle content) x 10,000 = 10 to 1,240

4. 2. The abrasive particles according to claim 1, wherein the difference in isoelectric point (IEP) before and after centrifugation is 1 or less.

5. BET value is 175m ２ 10. The abrasive particle of claim 1, wherein the abrasive particle has a surface roughness of less than 1 / g.

6. The BET value is 20 to 170 m ２ The abrasive particles according to claim 5, wherein the abrasive particle has a surface roughness of 1 / g.

7. 3. The abrasive particle of claim 2, wherein the modifier is 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.

8. The abrasive particles according to claim 1, wherein the nitrogen content of the abrasive particles is 0.00001 to 0.5 wt % as measured using a nitrogen analyzer based on 100 wt % of the abrasive particle solid content obtained after centrifuging a slurry containing the surface-modified abrasive particles.

9. An abrasive slurry composition comprising the abrasive particles according to claim 1 and a solvent.

10. 10. The polishing slurry composition of claim 9, wherein the abrasive particles comprise 0.01 to 30 wt % based on the total weight of the polishing slurry composition.

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

12. The abrasive slurry composition of claim 9 , further comprising an organic acid.

13. The abrasive slurry composition of claim 9 , further comprising an oxidizing agent.

14. The polishing slurry composition according to claim 9, further comprising at least one selected from the group consisting of a catalyst, a biocide, a pH adjuster, a corrosion inhibitor, a defect improving agent, and a pad protecting agent.

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