Polishing composition for semiconductor process and method for manufacturing substrate using same

Abstract

A polishing composition for a semiconductor process according to one embodiment of the present specification includes polishing particles, a polishing pad protective agent, and a fluorosurfactant. The polishing composition for a semiconductor process has an Rm / e value of 2.5% or less, said Rm / e value being the number ratio value of organic-substance-derived defects in the following formula 1. In the formula 1, the De value is the number of defects detected on the whole upper surface of a substrate after the upper surface of the substrate is polished by the polishing composition for the semiconductor process and the polished upper surface of the substrate is etched back. The Dm value is the number of defects corresponding to organic matter-derived defects among the selected defects when 100 defects are arbitrarily selected from the defects detected on the whole upper surface of the polished and etched-back substrate. In this case, the surface to be polished, which has been polished and etched back, can be prevented from being contaminated by particles, particularly organic particles. Formula 1: # imgabs0 #

Description

Technical Field

[0001] Examples relate to a polishing composition for semiconductor processing and a method for manufacturing a substrate using the composition. Background Art

[0002] As semiconductor devices become more sophisticated and denser, more sophisticated pattern forming technologies are being used, so the surface structure of semiconductor devices becomes more complex and the height difference of interlayer films becomes larger. When manufacturing semiconductor devices, a chemical mechanical polishing (CMP) process is used as a flattening technology for eliminating the height difference on a specific film formed on a substrate.

[0003] The CMP process is a process in which a substrate is pressurized, rotated, and the surface is polished while a slurry is provided on a polishing pad. Depending on the process steps, the object to be flattened is different, and the physical properties of the slurry applicable at this time are also different.

[0004] Polishing after forming metal wiring needs to minimize dishing and erosion while maintaining a sufficient polishing rate and polishing speed.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Korean Patent Publication No. 10-2015-0036422

[0008] Patent Document 2: Korean Patent Publication No. 10-2020-0104257 Summary of the invention

[0009] Technical issues

[0010] The purpose of the embodiment is to provide a polishing composition for semiconductor process, which, when applied to CMP process, can effectively reduce the degree of particle contamination, especially organic particle contamination, on the polished surface after polishing and etching back.

[0011] Solutions to the problem

[0012] A polishing composition for semiconductor processes according to one embodiment of the present specification includes polishing particles, a polishing pad protective agent, and a fluorine surfactant.

[0013] The polishing composition for semiconductor process may have a value of organic matter-derived defect number ratio Rm / e of the following Formula 1 of 2.5% or less.

[0014] [Formula 1]

[0015]

[0016] In Formula 1, the De value is the number of defects detected on the entire upper surface of the substrate after the upper surface of the substrate is polished using the semiconductor process polishing composition and the polished upper surface of the substrate is etched back.

[0017] The Dm value is the number of defects corresponding to organic-derived defects among 100 defects randomly selected from the defects detected on the entire upper surface of the substrate after polishing and etching back.

[0018] The polishing pad protective agent may include a sugar alcohol.

[0019] The sugar alcohol may be any one selected from the group consisting of sorbitol, mannitol, galactitol, fucitol, iditol, inositol, arabitol, xylitol, erythritol, threitol, and a combination thereof.

[0020] The fluorine surfactant may be a fluorine surfactant of the following Chemical Formula 1.

[0021]

Chemical formula 1

[0022] R f -(R en -O) n -H

[0023] In the chemical formula 1, the R f is a fluoroalkyl group having 3 to 10 carbon atoms, wherein R en is an alkylene group having 2 or 3 carbon atoms, and n is an integer of 2 to 15.

[0024] The polishing composition for semiconductor process may include 1 wt % to 5 wt % of the polishing pad protectant.

[0025] The semiconductor process polishing composition may include 10 ppm (by weight) to 500 ppm (by weight) of the fluorosurfactant.

[0026] The semiconductor process polishing composition may further include a tungsten inhibitor.

[0027] The tungsten inhibitor may be any one selected from the group consisting of azole compounds, amino acids, and combinations thereof.

[0028] The pH of the semiconductor process polishing composition may be 2.5 to 5.

[0029] A method for manufacturing a substrate according to another embodiment of the present specification includes a step of using the polishing composition for a semiconductor process as a slurry to polish a substrate.

[0030] Effects of the Invention

[0031] The polishing composition for semiconductor process of the embodiment can effectively reduce the degree of particle contamination, especially the degree of organic particle contamination, of the polished surface after polishing and etching back. DETAILED DESCRIPTION

[0032] Hereinafter, the embodiments are described in detail so that those skilled in the art can easily implement the invention. However, the embodiments can be implemented in various forms and are not limited to the embodiments described herein.

[0033] The degree terms "about", "substantially" and the like as used in this specification are used to provide for inherent manufacturing and material tolerances in the mentioned meaning, when used on a numerical value or as a means close to that numerical value, to prevent unscrupulous infringers from improperly taking advantage of the disclosure that mentions exact or absolute values ​​to facilitate the understanding of the examples.

[0034] Throughout this specification, the term "combination thereof" included in the Markush form expression means a mixture or combination of one or more selected from the group consisting of constituent elements described in the Markush form expression, and means including one or more selected from the group consisting of the constituent elements.

[0035] Throughout the present specification, the description of "A and / or B" means "A, B, or, A and B".

[0036] Throughout the specification, unless otherwise specified, terms such as "first", "second" or "A", "B" and the like are used to distinguish the same term.

[0037] In the present specification, B being located on A means that B is located on A or B is located or can be located on A with other layers interposed therebetween, and should not be limitedly interpreted as B being located on A in contact with the surface of A.

[0038] In this specification, unless otherwise specified, a single form expression is interpreted as including the meaning of the single form or the plurality of forms explained in the context.

[0039] "-type compounds" include "-compounds" and their derivatives.

[0040] Particles derived from organic matter may be formed on the polished surface after the polishing and etch back processes are completed. The particles may have a sticky characteristic remaining on the polished surface and have a generally amorphous shape. Such organic particles are difficult to remove by a general cleaning process.

[0041] The contamination described above is considered to occur because organic substances remaining on the polished surface after the CMP process are not vaporized during the etch-back process in a high temperature environment, but remain and are adsorbed on the substrate surface.

[0042] The inventors of the example applied a polishing pad protective agent and a fluorine surfactant to the polishing composition, and adjusted the Rm / e value of the polishing composition to be within the preset range in the example. Thus, the inventors confirmed through experiments that the number of defects caused by organic particles can be effectively reduced on the polished surface after the polishing and etch-back processes, and completed the example.

[0043] Hereinafter, examples will be described in detail.

[0044] A polishing composition for semiconductor process according to an example includes polishing particles, a polishing pad protective agent, and a fluorine surfactant.

[0045] Physical properties of polishing compositions

[0046] The polishing composition for semiconductor process has an Rm / e value which is a ratio value of the number of organic matter-derived defects expressed in the following Formula 1 and is 2.5% or less.

[0047] [Formula 1]

[0048]

[0049] In the above formula 1, the value of De is the number of defects detected on the entire upper surface of the substrate after the upper surface of the substrate is polished with the polishing composition for semiconductor process and the polished upper surface of the substrate is etched back.

[0050] The Dm value is the number of defects corresponding to organic-derived defects among 100 defects randomly selected from the defects detected on the entire upper surface of the substrate after polishing and etching back.

[0051] Examples The Rm / e value of the polishing composition can be adjusted to be within a predetermined range, thereby suppressing the reduction in electrical characteristics of the device due to organic matter when manufacturing a device having a fine pattern, and enabling more effective improvement in the productivity of the device.

[0052] The Rm / e value of the polishing composition is determined by the following method.

[0053] Using the polishing composition, a substrate which is a wafer having a diameter of 300 mm was polished with a polishing machine. to A tungsten film is formed with a thickness of .

[0054] Polishing is performed under the conditions of polishing time 60 seconds, pressure 2.2 psi, carrier speed 93 rpm, platen speed 87 rpm, and slurry flow rate 300 ml / min. The polishing machine can be, for example, the AP-300 model of CTS, Korea, the REFLEXTION_LK model of AMAT, Korea, or the F_REX300X model of EBARA, Korea.

[0055] Etching back is performed on the polished substrate. Specifically, plasma etching is performed on the upper surface of the substrate using SF6 gas for 1 minute.

[0056] After the etching back is completed, the total number of defects formed on the wafer is measured by a defect measurement device, and the measured value is used as the value of De.

[0057] After etching back, 100 defects are randomly selected from the defects measured, and then an online scanning electron microscope (SEM) is used to determine whether the defects are organic-derived defects. Defects derived from organic matter refer to particles composed of organic matter. The number of organic-derived defects is calculated from the 100 selected defects, and this value is used as the Dm value.

[0058] The Rm / e value was calculated from the De value and the Dm value.

[0059] The Rm / e value of the polishing composition may be 2.0% or less. The Rm / e value may be 1.7% or less. The Rm / e value may be 1.5% or less. The Rm / e value may be 0.01% or more. In this case, organic defects in the polishing composition may be suppressed, thereby facilitating the production of devices with high yields.

[0060] The pH of the polishing composition for semiconductor process may be 2.5 to 5. The pH may be 3 or more. The pH may be 3.5 or more. In this case, the polishing characteristics of the polishing composition on the polished surface may be improved. Therefore, a lower content of polishing particles may be applied to the polishing composition, thus helping to reduce the frequency of particle adsorption formed on the polished surface.

[0061] The pH of the polishing composition is measured with a pH meter.

[0062] The zeta potential of the polishing composition for semiconductor process may be +5 mV to +50 mV, the zeta potential may be above +10 mV, or below +40 mV.

[0063] The zeta potential of the polishing particles may be between +5 mV and +50 mV. The zeta potential may be above +10 mV. The zeta potential may be below +40 mV.

[0064] In this case, the polishing composition can exhibit stable dispersibility and, at the same time, can exhibit excellent polishing characteristics for a silicon oxide film showing a negative surface charge.

[0065] The conductivity of the polishing composition for semiconductor process may be 20 μS / cm or more. The conductivity may be 40 μS / cm or more. The conductivity may be 70 μS / cm or more. The conductivity may be 100 μS / cm or more. The conductivity may be 400 μS / cm or less. In this case, the polishing composition can help polish the polished surface at an excellent polishing speed.

[0066] Composition of polishing composition

[0067] Polishing particles

[0068] The polishing composition can contain polishing particles.

[0069] The polishing particles may include metal oxide particles and / or silicon oxide particles. The polishing particles may include silica. The polishing particles may include colloidal silica.

[0070] The polishing particles may contain 70% or more of colloidal silica by weight. The polishing particles may contain 80% or more of colloidal silica by weight. The polishing particles may contain 90% or more of colloidal silica by weight. The polishing particles may be colloidal silica.

[0071] The polishing particles may have a positive charge on their surface. The polishing particles may be surface modified to have a positive charge on their surface. The polishing particles may be surface modified with a compound having an amine group. The polishing particles may be surface modified with an aminosilane.

[0072] For example, the aminosilane may be selected from 3-aminopropyltriethoxysilane, bis[(3-triethoxysilane)propyl]amine, 3-aminopropyltrimethoxysilane, bis[3-(trimethoxysilane)propyl]amine, 3-aminopropylmethyldiethoxysilane, 3-aminopropylmethyldimethoxysilane, N-[3-(trimethoxysilane)propyl]ethylenediamine, N-bis[3-(trimethoxysilane)propyl]-1,2- Any one of the group consisting of ethylenediamine, N-[3-(triethoxysilyl)propyl]ethylenediamine, diethylenetriaminopropyltrimethoxysilane, diethylenetriaminopropylmethyldimethoxysilane, diethylaminomethyltriethoxysilane, diethylaminopropyltrimethoxysilane, diethylaminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, N-[3-(trimethoxysilyl)propyl]n-butylamine and combinations thereof.

[0073] The polishing composition for semiconductor process may contain 15ppm (by weight) to 200ppm (by weight) of aminosilane. The polishing composition for semiconductor process may contain 20ppm (by weight) or more of aminosilane. The polishing composition for semiconductor process may contain 25ppm (by weight) or more of aminosilane. The polishing composition for semiconductor process may contain 30ppm (by weight) or more of aminosilane. The polishing composition for semiconductor process may contain 150ppm (by weight) or less of aminosilane. The polishing composition for semiconductor process may contain 100ppm (by weight) or less of aminosilane. The polishing composition for semiconductor process may contain 70ppm (by weight) or less of aminosilane. The polishing composition for semiconductor process may contain 50ppm (by weight) or less of aminosilane. In this case, the polishing composition has a more excellent polishing rate for silicon oxide film, can polish the surface of the substrate to be polished more smoothly, and can show improved dispersibility. At the same time, the residue of the surface modifier is generated, which can effectively inhibit the residue from being adsorbed onto the polished surface.

[0074] The polishing composition for semiconductor process may contain 1 wt % to 10 wt % of polishing particles. The polishing composition for semiconductor process may contain more than 2 wt % of polishing particles. The polishing composition for semiconductor process may contain less than 8 wt % of polishing particles. The polishing composition for semiconductor process may contain less than 5 wt % of polishing particles. In this case, the polishing composition may have an excellent polishing rate to the polished surface and may stably suppress the aggregation of the polishing particles.

[0075] The average particle size of the polishing particles may be 20 nm or more. The particle size may be 30 nm or more. The particle size may be 40 nm or more. The particle size may be 70 nm or less. The particle size may be 60 nm or less. The particle size may be 50 nm or less. In this case, the polishing composition may exhibit an excellent polishing rate on the polished surface, and may stably adjust the frequency of defects occurring on the polished surface.

[0076] The average particle size refers to the average particle size of primary particles of the polishing particles.

[0077] Polishing pad protector

[0078] The polishing pad protective agent of the example can effectively reduce the wear degree of the polishing pad during the CMP process, and help reduce the frequency of the polishing pad debris being adsorbed on the surface of the substrate to be polished.

[0079] The polishing pad protective agent of the example may include sugar alcohol. As the pad protective agent of sugar alcohol, it is attached to the surface of the pad protective agent during the polishing process, and the pad protective agent can be stably protected. In addition, sugar alcohol has the characteristic of being difficult to be used as a nutrient component of bacteria, so the excessive reproduction of microorganisms in the composition can be suppressed by applying sugar alcohol to the polishing composition, and the pollution of the device production line can be effectively suppressed by the microorganism. Sugar alcohol can be any one selected from the group consisting of sorbitol, mannitol, galactitol, fucitol, iditol, inositol, arabitol, xylitol, erythritol, threitol and their combination. Sugar alcohol can be sorbitol.

[0080] The polishing pad protective agent may contain 50% by weight or more of a sugar alcohol. The polishing pad protective agent may contain 60% by weight or more of a sugar alcohol. The polishing pad protective agent may contain 70% by weight or more of a sugar alcohol. The polishing pad protective agent may contain 100% by weight or less of a sugar alcohol. The polishing pad protective agent may be a sugar alcohol.

[0081] The polishing composition for semiconductor process may contain 1 wt % to 5 wt % of a polishing pad protective agent. The polishing composition for semiconductor process may contain 1.5 wt % or more of a polishing pad protective agent. The polishing composition for semiconductor process may contain 4 wt % or less of a polishing pad protective agent. When the polishing composition as described above is applied to a polishing process, contamination of the surface of a substrate after polishing due to organic-derived particles can be suppressed.

[0082] Fluorinated surfactants

[0083] Examples Fluorine surfactants can be applied to polishing compositions. The surfactants adsorb on the surface of polishing pad fragments generated during the polishing process, thereby further improving the hydrophilicity of the fragments. Thus, the fragments can be effectively prevented from being adsorbed on the polished surface. In addition, the fluorine groups contained in the fluorine surfactants help the surfactants kill bacteria or various microorganisms, and help reduce the number of defects caused by organic particles detected on the polished surface.

[0084] The fluorine surfactant may be a fluoroalkyl epoxyalkyl compound. The fluorine surfactant may be a compound represented by the following Chemical Formula 1.

[0085]

Chemical formula 1

[0086] R f -(R en -O) n -H

[0087] In the chemical formula 1, the R f is a fluoroalkyl group having 3 to 10 carbon atoms, wherein R en is an alkylene group having 2 or 3 carbon atoms, and n is an integer of 2 to 15.

[0088] In the chemical formula 1, R f The perfluoroalkyl group may be a group having 3 to 10 carbon atoms.

[0089] The fluorine surfactant may be a polymer surfactant. The weight average molecular weight of the fluorine surfactant may be 150 g / mol to 3000 g / mol. The weight average molecular weight may be 300 g / mol or more. The weight average molecular weight may be 500 g / mol or more. The weight average molecular weight may be 2500 g / mol or less. The weight average molecular weight may be 2000 g / mol or less. The weight average molecular weight may be 1500 g / mol or less.

[0090] The fluorine surfactant having the above-mentioned characteristics has a main chain length adjusted so that polishing pad debris can be effectively discharged and thereby the excessive increase in the dispersibility of the polishing composition can be prevented.

[0091] The weight average molecular weight of the polymer surfactant is measured by (Gel Permeation Chromatography, GPC).

[0092] In the example, the content of the fluorinated surfactant can be adjusted within a preset range, thereby preventing organic particles from being attached to the polished surface after polishing, and preventing excessive bubbles from being generated in the polishing composition during the polishing process to prevent degradation of processability.

[0093] The polishing composition for semiconductor process may contain more than 10 ppm (based on weight) of fluorine surfactant. The polishing composition for semiconductor process may contain more than 20 ppm (based on weight) of fluorine surfactant. The polishing composition for semiconductor process may contain more than 50 ppm (based on weight) of fluorine surfactant. The polishing composition for semiconductor process may contain more than 100 ppm (based on weight) of fluorine surfactant. The polishing composition for semiconductor process may contain more than 150 ppm (based on weight) of fluorine surfactant. The polishing composition for semiconductor process may contain less than 500 ppm (based on weight) of fluorine surfactant. The polishing composition for semiconductor process may contain less than 450 ppm (based on weight) of fluorine surfactant. In this case, the hydrophilicity of the polishing pad debris can be effectively improved, while suppressing the generation of excessive bubbles during the polishing process.

[0094] Tungsten Inhibitors

[0095] The polishing composition for semiconductor processing may further include a tungsten inhibitor.

[0096] In the surface of the substrate to be polished, especially the tungsten film, there is a tendency that organic particles such as bacteria or microorganisms are more frequently adsorbed on the surface compared with other thin films. The polishing composition of the example can make the tungsten inhibitor adhere to the surface of the tungsten film during the polishing process. The tungsten inhibitor can effectively hinder the adhesion of organic particles on the tungsten film and inhibit excessive corrosion of the tungsten film.

[0097] The tungsten inhibitor may be any one selected from the group consisting of azole compounds, amino acids, and combinations thereof.

[0098] The azole compound is a five-membered heterocyclic compound, and is a compound containing a nitrogen atom and one or more non-carbon atoms in the ring and / or its derivatives.

[0099] The azole compound can be any one selected from the group consisting of triazole, benzotriazole, imidazole, pyrazole, tetrazole, aminotetrazole, pentazole, oxazole, isoxazole, oxadiazole, furazan, thiazole, isothiazole, thiadiazole, their derivatives and their combinations.

[0100] The amino acid may be any one selected from the group consisting of glycine, threonine, arginine, aspartic acid, cystine, cysteine, glutamine, glutamic acid, histidine, isoleucine, leucine, α-alanine, lysine, methionine, phenylalanine, proline, serine, tryptophan, tyrosine, valine, and combinations thereof. The amino acid may be glycine.

[0101] The polishing composition for semiconductor process may contain 0.01 wt % to 0.5 wt % of tungsten inhibitor. The polishing composition for semiconductor process may contain 0.02 wt % or more of tungsten inhibitor. The polishing composition for semiconductor process may contain 0.3 wt % or less of tungsten inhibitor. The polishing composition for semiconductor process may contain 0.2 wt % or less of tungsten inhibitor. The polishing composition for semiconductor process may contain 0.1 wt % or less of tungsten inhibitor. In this case, the adsorption of organic foreign matter on the surface of the tungsten film can be suppressed, and the corrosion of the tungsten film can be prevented. In addition, by preventing the pH of the polishing composition from being too high due to the tungsten inhibitor, the reduction of the polishing characteristics of the polishing composition on the silicon oxide film can be suppressed.

[0102] Other additives

[0103] The semiconductor process polishing composition may further include other additives. The additives are not limited as long as they are conventionally used additives in the CMP field. For example, the additives may be at least one of an oxidizing agent, an acid component, a pH adjusting agent, a dispersant, a polishing rate enhancer, a polishing adjusting agent, and a preservative.

[0104] The polishing composition for semiconductor processing may further include an oxidizing agent. The role of the oxidizing agent is to oxidize metals such as tungsten, create an environment that makes it easier to planarize the substrate surface, and increase the polishing rate and etching rate.

[0105] The oxidizing agent can be at least one selected from the group consisting of hydrogen peroxide, urea hydrogen peroxide, urea, percarbonate, periodic acid, periodate, perchloric acid, perchlorate, perbromic acid, perbromate, perboric acid, perborate, permanganic acid, permanganate, persulfate, bromate, chlorate, chlorite, chromate, iodate, iodic acid, ammonium persulfate, benzoyl peroxide, calcium peroxide, barium peroxide, sodium peroxide and urea peroxide.

[0106] The polishing composition for semiconductor process may contain 0.01 wt % to 5 wt % of an oxidizing agent. In this case, the composition may exhibit excellent polishing characteristics for metals and may suppress the formation of an oxide film on the metal to be polished during polishing.

[0107] The polishing composition for semiconductor processing further comprises an acid component. The acid component can be, for example, at least one selected from the group consisting of hydrochloric acid, phosphoric acid, sulfuric acid, hydrofluoric acid, bromic acid, iodic acid, formic acid, malonic acid, maleic acid, oxalic acid, acetic acid, adipic acid, citric acid, adipic acid, acetic acid, propionic acid, fumaric acid, lactic acid, salicylic acid, pimelic acid, benzoic acid, succinic acid, phthalic acid, butyric acid, glutaric acid, glutamic acid, glycolic acid, lactic acid, aspartic acid, tartaric acid and salts thereof.

[0108] The polishing composition for semiconductor processing may contain an acid component and a pH adjuster. The pH adjuster may be any one selected from the group consisting of ammonia, aminopropanol, tetramethylammonium hydroxide, potassium hydroxide, sodium hydroxide, magnesium hydroxide, rubidium hydroxide, cesium hydroxide, sodium bicarbonate, sodium carbonate, imidazole, and combinations thereof.

[0109] The polishing composition for semiconductor processing may further comprise a dispersant.

[0110] The dispersant can prevent aggregation of polishing particles in the polishing composition and make them uniformly dispersed. Cationic dispersants can increase the zeta potential of the polishing composition to a positive (+) value, and anionic dispersants can reduce the zeta potential of the polishing composition to a negative (-) value.

[0111] The dispersant may include anionic low molecular weight, cationic high molecular weight, organic acid and the like.

[0112] The anionic low molecular weight dispersant may be one or more selected from oxalic acid, citric acid, polysulfonic acid, polyacrylic acid, polymethacrylic acid, and combinations thereof.

[0113] The cationic polymer of the dispersant can be one or more selected from polylysine, polyethyleneimine, benzethonium chloride, 5-bromo-5-nitro-1,3-dioxane (bronidox), hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, dimethyldioctadecylammonium chloride, tetramethylammonium hydroxide, dioctadecyldimethylammonium chloride, polyarylamines and combinations thereof.

[0114] The organic acid of the dispersant may be one or more selected from hydroxybenzoic acid, ascorbic acid, picolinic acid, glutamic acid, tryptophan, aminobutyric acid and combinations thereof.

[0115] The polishing rate enhancer is an additive used to improve the polishing rate of the substrate or wiring to be polished, and can be one or more selected from potassium nitrate, ferric nitrate, ammonium hydroxide, citric acid, acetic acid and combinations thereof.

[0116] The polishing conditioner is used to minimize the adsorption of the polishing composition on the metal surface, and may include ammonium compounds, potassium nitrate, amino acids, salts thereof, and the like.

[0117] The polishing composition for semiconductor process may contain a solvent, which may be water, and specifically, ultrapure water.

[0118] Polishing properties of polishing compositions

[0119] The polishing rate of the semiconductor process polishing composition for silicon oxide film can be / minute or more. The polishing rate may be / minute or more. The polishing rate may be / minute or more. The polishing rate may be / minute or less. The polishing rate may be / minute or less. The polishing rate may be / min or less.

[0120] The polishing rate of the semiconductor process polishing composition for tungsten film can be / minute or more. The polishing rate may be / minute or more. The polishing rate may be / minute or less. The polishing rate may be / minute or less. The polishing rate may be / min or less.

[0121] The polishing selectivity of the polishing composition for semiconductor process to the silicon oxide film of the tungsten film may be 5 or more. The polishing selectivity may be 6 or more. The polishing selectivity may be 7 or more. The polishing selectivity may be 20 or less.

[0122] In this case, the polishing composition can show an excellent selectivity ratio of the silicon oxide film polishing rate compared to the tungsten polishing rate.

[0123] The Ra value of the tungsten film measured after polishing with the semiconductor process polishing composition for 30 seconds may be 3 nm or less. The Ra value may be 2 nm or less. In this case, the polishing composition can provide a polished surface with a smoother surface.

[0124] The Ra value is determined according to ISO 4287.

[0125] Polishing of each film was performed under the conditions of a pressure of 2.2 psi, a carrier speed of 87 rpm, a platen speed of 93 rpm, and a slurry flow rate of 250 ml / min. The polishing pad used was the SR-300 model of SK Enpulse Co., Ltd. of South Korea.

[0126] When the polishing rate of each thin film is measured, the polishing machine may exemplarily use the AP-300 model of CTS Corporation of Korea.

[0127] Method for manufacturing substrate

[0128] The method for manufacturing a substrate of the example includes a process of polishing a substrate using the polishing composition for semiconductor processes as a slurry.

[0129] The substrate may include at least one of an insulating film, a metal wiring and a barrier layer on the upper surface. The metal wiring may include copper or tungsten. When the metal wiring includes copper, the barrier layer may include tantalum and its nitride. When the metal wiring includes tungsten, the barrier layer may include titanium and its nitride.

[0130] Specifically, when the substrate is polished, the substrate to be polished is brought into contact with the semiconductor process polishing composition supplied from a nozzle on the polishing pad, and the polishing head fixing the substrate rotates, and the top plate attached with the polishing pad also rotates.

[0131] The method for manufacturing a substrate may include a process of polishing a tungsten film exposed on an upper surface of the substrate for 5 seconds to 20 seconds using a semiconductor process polishing composition (partial CMP).

[0132] The method for manufacturing a substrate may include a process of polishing a tungsten bulk film formed on an upper surface of the substrate using a semiconductor process polishing composition to separate nodes.

[0133] If necessary, the process of polishing the substrate may further include a process of adjusting the surface of the polishing pad before polishing.

[0134] The polishing composition for semiconductor processing can penetrate toward the substrate and polish the wafer in contact with the polishing pad at the same time.

[0135] During polishing of the substrate, a pressure of 6.89 kPa to 48.26 kPa may be applied. The pressure may be 13.79 kPa to 34.47 kPa.

[0136] The process of polishing the substrate may be performed for 50 seconds to 10 minutes, but this may be varied depending on the desired polishing degree.

[0137] The description of the polishing composition for semiconductor process overlaps with the above description and is therefore omitted.

[0138] The method for manufacturing a substrate may further include a cleaning process of cleaning the polished substrate.

[0139] The cleaning process may be performed by using pure water and inactive gas to clean the polished substrate.

[0140] The following embodiments are only examples for helping to understand the present invention, and the scope of the present invention is not limited thereto.

[0141] Preparation Example: Preparation of polishing composition

[0142] Example 1: In ultrapure water as a solvent, 3 wt % of colloidal silica surface-modified with 38 ppm (by weight) of (3-aminopropyl)triethoxysilane as polishing particles, 2 wt % of sorbitol as a polishing pad protective agent, and 50 ppm (by weight) of FS 3100 produced by Capstone, USA, as a fluorosurfactant were added and mixed to prepare a polishing composition of 100 wt %.

[0143] Example 2: A total of 100 wt% of a polishing composition was prepared under the same conditions as in Example 1 except that 0.05 wt% of glycine was further added as a tungsten inhibitor and the average particle size of the polishing particles, pH, conductivity, and zeta potential of the polishing composition were applied as shown in Table 1.

[0144] Example 3: A polishing composition of 100 wt % was prepared under the same conditions as in Example 1 except that the average particle size of the polishing particles, pH, conductivity, and zeta potential of the polishing composition were as shown in Table 1.

[0145] Comparative Example 1: As polishing pad protective agents, 1 wt% sorbitol and 2 wt% sucrose were used, and as tungsten inhibitors, 0.05 wt% aminotetrazole, 0.05 wt% glycine, and 0.05 wt% imidazole were further used. The difference between edible alkali and baking soda was shown in Table 1. The average particle size of the polishing particles, the pH value, the electrical conductivity, and the zeta potential of the polishing composition were used. In addition, a total of 100 wt% of the polishing composition was prepared under the same conditions as in Example 1.

[0146] Comparative Example 2: A polishing composition of 100 wt% was prepared under the same conditions as in Comparative Example 1 except that 25 ppm (based on weight) of fluorosurfactant was used, and the average particle size of the polishing particles, pH, conductivity, and zeta potential of the polishing composition were applied as shown in Table 1.

[0147] The content of each component in the polishing composition of each example and comparative example and the average particle size (primary particle size) of the polishing particles are recorded in Table 1 below, and the pH, conductivity, and zeta potential of the polishing composition are recorded in Table 2 below.

[0148] Evaluation Example: Determination of the number of defects on the polished surface and the polishing rate of the polishing composition

[0149] The polishing compositions of the embodiments and comparative examples were used to polish the upper surface of a wafer having a diameter of 300 mm using an AP-300 polishing machine of CTS Co., Ltd., South Korea. to A tungsten film is formed with a thickness of .

[0150] Polishing was performed under the following conditions: polishing time 60 seconds, pressure 2.2 psi, carrier speed 93 rpm, platen speed 87 rpm, and slurry flow rate 300 ml / min.

[0151] The polished wafer was subjected to an etch-back process using SF6 gas plasma etching for 1 minute.

[0152] After the etching back is completed, the total number of defects formed on the wafer is measured by a defect measurement device, and the measured value is used as the value of De.

[0153] Next, 100 defects are randomly selected from the defects to be measured, and an online scanning electron microscope (SEM) is used to confirm whether the selected defects are organic-derived defects, that is, whether they are organic particles. The number of organic-derived defects among the selected 100 defects is calculated and the value is taken as the Dm value.

[0154] The Rm / e value was calculated from the De value and the Dm value.

[0155] The measured values ​​and calculated values ​​of each of the examples and comparative examples are shown in Table 3 below.

[0156] Then, the height difference of the tungsten film and the height difference of the silicon oxide film before and after polishing were measured from the polished wafer, and the polishing rate of the tungsten film and the polishing rate of the silicon oxide film were calculated from the values.

[0157] The measured values ​​and calculated values ​​of each of the examples and comparative examples are shown in Table 2 below.

[0158] Evaluation example: Measurement of pad wear rate

[0159] The height of the polishing pad of SR-300 model of SK Enpulse Co., Ltd. was measured by a profiler. Then, the tungsten film formed on the upper surface of a wafer having a diameter of 300 mm was continuously polished using the polishing pad and the polishing composition of each embodiment and comparative example and an AP-300 polisher of CTS Co., Ltd. of Korea.

[0160] Polishing was performed under the conditions of a pressure of 2.2 psi, a carrier speed of 93 rpm, a platen speed of 87 rpm, and a slurry flow rate of 300 ml / min. During polishing, the CMP process was performed without changing the polishing pad until the cumulative polishing process time reached 20 hours.

[0161] After polishing, the height of the polishing pad is measured using a step profiler.

[0162] The height difference of the polishing pad before and after polishing was calculated, and the pad wear rate was calculated by dividing the height difference by the polishing time.

[0163] The calculated values ​​of each embodiment and comparative example are shown in Table 3 below.

[0164] Evaluation Example: Measurement of Bubble Generation Amount

[0165] 3 L of the polishing composition of each example and comparative example was added to a glass reactor having a volume of 5 L. The added polishing composition was stirred at a speed of 1000 RPM at 25° C. for 30 minutes using a four-blade blade having a total length of 10 cm. After 10 minutes had passed from the time when the stirring was completed, the height of the bubbles formed in the glass reactor was measured. The volume of the bubbles was calculated from the height value and the inner diameter of the glass reactor containing the polishing composition.

[0166] The bubble volume values ​​calculated for each embodiment and comparative example are shown in Table 3 below.

[0167] Table 1

[0168]

[0169] Table 2

[0170]

[0171]

[0172] Table 3

[0173] Rm / e(%) Pad wear rate (μm / hour) Bubble volume (ml) Example 1 0.88 32.8 30 Example 2 0.50 32.5 25 Example 3 0.45 28.6 30 Comparative Example 1 2.71 35.7 50 Comparative Example 2 3.19 33.1 20

[0174] In Table 3, regarding the Rm / e value, Examples 1 to 3 showed values ​​of 1% or less, whereas Comparative Examples 1 and 2 showed values ​​of 2.5% or more.

[0175] Regarding the pad wear rate, the Examples showed lower values ​​than the Comparative Examples.

[0176] As for the bubble volume, Examples 1 to 3 showed a value of 30 ml or less. This means that the degree of bubble generation during polishing can be controlled below a predetermined level in the case of Examples.

[0177] The preferred embodiments are described in detail above, but the scope of protection of the invention claimed by the present invention is not limited thereto. Various deformations and improvements made by ordinary technicians in the technical field to which the present invention belongs using the basic concepts of the examples defined in the attached scope of protection of the invention also fall within the scope of protection of the invention claimed by the present invention.

Claims

1. A polishing composition for semiconductor processing, wherein: The semiconductor process polishing composition comprises: Polishing particles, Polishing pad protector, and Fluorinated surfactants; The polishing composition for semiconductor process has an organic matter-derived defect number ratio Rm / e value of the following formula 1 of 2.5% or less, Formula 1 In the formula 1, The De value is the number of defects detected on the entire upper surface of the substrate after the upper surface of the substrate is polished with the polishing composition for semiconductor process and the polished upper surface of the substrate is etched back. The Dm value is the number of defects corresponding to organic-derived defects among 100 defects randomly selected from the defects detected on the entire upper surface of the substrate after polishing and etching back.

2. The semiconductor process polishing composition according to claim 1, wherein The polishing pad protective agent includes a sugar alcohol.

3. The semiconductor process polishing composition according to claim 2, wherein: The sugar alcohol is any one selected from the group consisting of sorbitol, mannitol, galactitol, fucitol, iditol, inositol, arabitol, xylitol, erythritol, threitol and a combination thereof.

4. The semiconductor process polishing composition according to claim 1, wherein The fluorine surfactant is a fluorine surfactant of the following chemical formula 1; Chemical formula 1 R f -(R en -O) n -H In the chemical formula 1, the R f is a fluoroalkyl group having 3 to 10 carbon atoms, wherein R en is an alkylene group having 2 or 3 carbon atoms, and n is an integer of 2 to 15.

5. The semiconductor process polishing composition according to claim 1, wherein The polishing composition for semiconductor process comprises 1 wt % to 5 wt % of the polishing pad protective agent.

6. The semiconductor process polishing composition according to claim 1, wherein The semiconductor process polishing composition contains 10 ppm to 500 ppm of the fluorine surfactant on a weight basis.

7. The semiconductor process polishing composition according to claim 1, wherein The semiconductor process polishing composition further comprises a tungsten inhibitor, The tungsten inhibitor is any one selected from the group consisting of azole compounds, amino acids, and combinations thereof.

8. The semiconductor process polishing composition according to claim 1, wherein The pH of the semiconductor process polishing composition is 2.5 to 5.

9. A method for manufacturing a substrate, wherein: The method comprises the step of using the polishing composition for semiconductor process according to claim 1 as a slurry to polish a substrate.

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