Polishing composition for semiconductor process, and method for manufacturing substrate by using the same

Abstract

To provide a polishing composition for semiconductor process which can effectively reduce a degree of contamination by particles on a polished surface, whose polishing and etch back ended, in applying the composition to a CMP step.SOLUTION: A polishing composition for semiconductor process contains polishing particles, polishing pad protective agent and fluorine-based surfactant, and Rm / e value which is a ratio value of the number of defects derived from organic substance of the following formula is 2.5% or less. In the formula, De value is the number of defects detected on the entire top face of the substrate after polishing the top face of the substrate by the polishing composition for semiconductor process, and etching back the top face of the polished substrate, and Dm value is the number of defects corresponding to defects derived from the organic substance out of selected defects in arbitrarily selecting 100 defects in total from defects detected on the entire top face of the substrate whose polishing and etch back ended.SELECTED DRAWING: None

Description

Technical Field

[0001] Embodiments relate to a polishing composition for semiconductor processes, a method for manufacturing a substrate using the same, and the like.

Background Art

[0002] As semiconductor elements are further miniaturized and densified, even finer patterning technologies are being used, which has made the surface structure of semiconductor elements more complex and the step of the interlayer film even larger. In manufacturing semiconductor elements, a chemical mechanical polishing (hereinafter referred to as "CMP") process is used as a planarization technology for removing steps in a specific film formed on a substrate.

[0003] In the CMP process, while slurry is supplied to a polishing pad, the substrate is pressurized and rotated to polish the surface. Depending on the stage of the process, the object to be planarized changes, and there are also differences in the physical properties of the slurry applied at this time.

[0004] After forming the metal wiring, it is necessary to maintain a sufficient polishing rate and polishing speed while minimizing dishing or erosion.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] The object of the embodiment is to provide a polishing composition for semiconductor processes that can effectively reduce the degree to which the polished surface after polishing and etch-back is contaminated by particles, particularly organic particles, when applied to the CMP process.

Means for Solving the Problems

[0007] The polishing composition for semiconductor processes according to an embodiment of the present specification includes polishing particles, a polishing pad protector, and a fluorine-based surfactant.

[0008] In the polishing composition for semiconductor processes, the Rm / e value, which is the ratio of the number of defects derived from the organic substance of the following Formula 1, is 2.5% or less.

[0009] [Formula 1] JPEG2025078075000001.jpg1042

[0010] In Formula 1, the De value is the number of defects detected over the entire upper surface of the substrate after polishing the upper surface of the substrate with the polishing composition for semiconductor processes and then performing etch-back on the polished upper surface of the substrate.

[0011] The Dm value is the number of defects corresponding to defects derived from organic substances among the selected defects when arbitrarily selecting 100 defects from the defects detected over the entire upper surface of the substrate after finishing polishing and etch-back.

[0012] The polishing pad protector may contain sugar alcohol.

[0013] The sugar alcohol may be any one selected from the group consisting of sorbitol, mannitol, galactitol, fucitol, iditol, inositol, arabitol, xylitol, erythritol, threitol, and combinations thereof.

[0014] The fluorosurfactant may be a fluorosurfactant represented by the following Chemical Formula 1.

[0015]

Chem.

[0016] In the Chemical Formula 1, the R f is a fluoroalkyl group having 3 to 10 carbon atoms, the R en is an alkylene group having 2 or 3 carbon atoms, and n is an integer of 2 to 15.

[0017] The polishing composition for semiconductor processes may contain 1 wt% to 5 wt% of the polishing pad protector.

[0018] The polishing composition for semiconductor processes may contain 10 ppm (by weight) to 500 ppm (by weight) of the fluorosurfactant.

[0019] The polishing composition for semiconductor processes may further contain a tungsten inhibitor.

[0020] The tungsten inhibitor may be any one selected from the group consisting of azole compounds, amino acids, and combinations thereof.

[0021] The polishing composition for semiconductor processes may have a pH of 2.5 to 5.

[0022] The method for manufacturing a substrate according to another embodiment of the present specification includes a process of applying the polishing composition for semiconductor processes as a slurry to polish the substrate.

Advantages of the Invention

[0023] In the case of the polishing composition for semiconductor processes of the embodiment, it is possible to effectively reduce the degree to which the polished surface after polishing and etch-back is contaminated by particles, particularly organic particles.

Best Mode for Carrying Out the Invention

[0024] Hereinafter, the embodiments will be described in detail so that those having ordinary knowledge in the technical field to which the embodiments belong can easily implement them. However, the embodiments can be implemented in various different forms and are not limited to the embodiments described herein.

[0025] As used herein, terms such as "about" and "substantially" are used in the sense of the numerical value or close to the numerical value when manufacturing and material tolerances inherent in the mentioned meaning are presented, and are used to prevent unscrupulous infringers from improperly using the disclosed content where exact or absolute numerical values are mentioned to assist in understanding the embodiments.

[0026] Throughout this specification, the term "combinations thereof" included in the Markush-type expressions means one or more mixtures or combinations selected from the group consisting of the components described in the Markush-type expressions, and means including one or more selected from the group consisting of the said components.

[0027] Throughout this specification, the description of "A and / or B" means "A, B, or A and B".

[0028] Throughout this specification, terms such as "first", "second" or "A", "B" are used to distinguish the same terms from each other unless otherwise specified.

[0029] In this specification, the meaning that B is located on A means that B can be located on A, or B can be located on A while another layer is located between them, and is not construed as being limited to B being located in contact with the surface of A.

[0030] In this specification, a singular expression is construed to include the singular or plural as interpreted in the context unless otherwise specified.

[0031] "~-based compound" includes "~ compound" and its derivatives.

[0032] Particles derived from organic substances can be formed on the polished surface after the grinding and etch back processes. The particles can have the characteristic of sticking to the surface of the polished surface and generally have an irregular shape. Such organic particles may not be easily removed by a general cleaning process.

[0033] It is considered that such contamination occurs because the organic substances remaining on the polished surface after the CMP process do not vaporize in the high-temperature etch back process and remain adsorbed on the substrate surface.

[0034] The inventors of the embodiment applied a polishing pad protector, a fluorine-based surfactant, etc. to the polishing composition, and adjusted the Rm / e value of the polishing composition within a preset range in the embodiment. Through this, the inventors experimentally confirmed that the number of defects generated by organic particles on the polished surface after the grinding and etch back processes can be effectively reduced, and the embodiment was completed.

[0035] Hereinafter, the embodiments will be specifically described.

[0036] The polishing composition for semiconductor processes according to the embodiment includes polishing particles, a polishing pad protector, and a fluorine-based surfactant.

[0037] Physical properties of the polishing composition The polishing composition for semiconductor processes has an Rm / e value, which is the ratio value of the number of defects derived from organic substances in Formula 1 below, of 2.5% or less.

[0038] [Formula 1] JPEG2025078075000003.jpg1042

[0039] In Formula 1, the De value is the number of defects detected over the entire upper surface of the substrate after polishing the upper surface of the substrate with the polishing composition for semiconductor processes and then etch back the polished upper surface of the substrate.

[0040] The Dm value is the number of defects corresponding to defects derived from organic substances among the selected defects when arbitrarily selecting 100 defects from the defects detected on the entire upper surface of the substrate after polishing and etch-back.

[0041] In an embodiment, by adjusting the Rm / e value of the polishing composition within a preset range, during the production of an element having a fine pattern, it is possible to suppress a decrease in the electrical characteristics of the element due to organic substances and further effectively increase the production yield of the element.

[0042] The Rm / e value of the polishing composition is measured by the following method.

[0043] Apply the polishing composition and polish a substrate, which is a 300-mm-diameter wafer, with a polishing machine. As the substrate, apply one having a tungsten film formed with a thickness of 100 Å to 1,000 Å over the entire upper surface.

[0044] The polishing is performed under the conditions of a polishing time of 60 seconds, 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. As the polishing machine, for example, the AP-300 model of CTS, the REFLEXTION_LK model of AMAT, or the F_REX300X model of EBARA can be applied.

[0045] Perform etch-back on the polished substrate. Specifically, perform plasma etching on the upper surface of the substrate with SF 6 gas for 1 minute.

[0046] After the etch-back is completed, measure the total number of defects formed on the wafer through defect measurement equipment, and use the measured value as the De value.

[0047] After etch-back, after arbitrarily selecting 100 of the measured defects, use an in-line SEM (Scanning Electron Microscope) to determine whether the defects are defects derived from organic substances. Defects derived from organic substances mean particles composed of organic substances. Calculate the number of defects derived from organic substances among the selected 100 defects, and use that value as the Dm value.

[0048] Calculate the Rm / e value from the De value and the Dm value.

[0049] 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 such cases, organic defects in the polishing composition are suppressed and can contribute to producing elements with a high yield.

[0050] The pH of the polishing composition for semiconductor processes can be 2.5 to 5. The pH may be 3 or more. The pH may be 3.5 or more. In such cases, the polishing characteristics of the polishing composition with respect to the surface to be polished can be improved. Thereby, a lower content of polishing particles can be applied to the polishing composition, which can contribute to reducing the frequency of particle adsorption formed on the surface to be polished.

[0051] The pH of the polishing composition is measured with a pH meter.

[0052] The zeta potential of the polishing composition for semiconductor processes can be +5 mV to +50 mV. The zeta potential may be +10 mV or more. The zeta potential may be +40 mV or less.

[0053] The zeta potential of the polishing particles can be +5 mV to +50 mV. The zeta potential may be +10 mV or more. The zeta potential may be +40 mV or less.

[0054] In such a case, the polishing composition can exhibit stable dispersibility and excellent polishing characteristics with respect to a silicon oxide film having a surface negative charge.

[0055] The electrical conductivity of the polishing composition for semiconductor processes may be 20 μS / cm or more. The electrical conductivity may be 40 μS / cm or more. The electrical conductivity may be 70 μS / cm or more. The electrical conductivity may be 100 μS / cm or more. The electrical conductivity may be 400 μS / cm or less. In such a case, it can help the polishing composition to polish the surface to be polished at an excellent polishing rate.

[0056] Composition of the polishing composition Polishing particles The polishing composition can contain polishing particles.

[0057] The polishing particles can contain metal oxide particles and / or silicon oxide particles. The polishing particles can contain silica. The polishing particles can contain colloidal silica.

[0058] The polishing particles may contain 70% by weight or more of colloidal silica. The polishing particles may contain 80% by weight or more of colloidal silica. The polishing particles may contain 90% by weight or more of colloidal silica. The polishing particles may be colloidal silica.

[0059] The polishing particles can have a positively charged surface. The polishing particles may be surface-modified so as to have a positively charged surface. The polishing particles may be surface-modified with a compound having an amine group. The polishing particles may be surface-modified with aminosilane.

[0060] The amino silane is, for example, any one selected from the group consisting of 3-aminopropyltriethoxysilane, bis[(3-triethoxysilyl)propyl]amine, 3-aminopropyltrimethoxysilane, bis[(3-trimethoxysilyl)propyl]amine, 3-aminopropylmethyldiethoxysilane, 3-aminopropylmethyldimethoxysilane, N-[3-(trimethoxysilyl)propyl]ethylenediamine, N-bis[3-(trimethoxysilyl)propyl]-1,2-ethylenediamine, N-[3-(triethoxysilyl)propyl]ethylenediamine, diethylenetriaminopropyltrimethoxysilane, diethylenetriaminopropylmethyldimethoxysilane, diethylaminomethyltriethoxysilane, diethylaminopropyltrimethoxysilane, diethylaminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, N-[3-(trimethoxysilyl)propyl]butylamine, and combinations thereof.

[0061] The polishing composition for semiconductor processes can contain 15 ppm (by weight) to 200 ppm (by weight) of amino silane. The polishing composition for semiconductor processes may contain 20 ppm (by weight) or more of amino silane. The polishing composition for semiconductor processes may contain 25 ppm (by weight) or more of amino silane. The polishing composition for semiconductor processes may contain 30 ppm (by weight) or more of amino silane. The polishing composition for semiconductor processes may contain 150 ppm (by weight) or less of amino silane. The polishing composition for semiconductor processes may contain 100 ppm (by weight) or less of amino silane. The polishing composition for semiconductor processes may contain 70 ppm (by weight) or less of amino silane. The polishing composition for semiconductor processes may contain 50 ppm (by weight) or less of amino silane. In such cases, the polishing composition has a better polishing rate for silicon oxide films, can polish the surface of the substrate to be polished more smoothly, and can exhibit improved dispersibility. At the same time, residues of the surface modifier are generated, and adsorption of the residues to the surface to be polished can be effectively suppressed.

[0062] The polishing composition for semiconductor processes can contain 1 wt% to 10 wt% of abrasive particles. The polishing composition for semiconductor processes may contain 2 wt% or more of abrasive particles. The polishing composition for semiconductor processes may contain 8 wt% or less of abrasive particles. The polishing composition for semiconductor processes may contain 5 wt% or less of abrasive particles. In such cases, the polishing composition has an excellent polishing rate with respect to the surface to be polished and can stably suppress the aggregation of abrasive particles.

[0063] The average particle size of the abrasive particles may be 20 nm or more. The average particle size may be 30 nm or more. The average particle size may be 40 nm or more. The average particle size may be 70 nm or less. The average particle size may be 60 nm or less. The average particle size may be 50 nm or less. In such cases, the polishing composition exhibits an excellent polishing rate with respect to the surface to be polished, and moreover, can stably adjust the frequency of defects occurring on the surface to be polished.

[0064] The average particle size means the average particle size of the primary particles of the abrasive particles.

[0065] Polishing pad protector The polishing pad protectant of the embodiment can effectively reduce the degree of wear of the polishing pad during the CMP process and contribute to reducing the frequency of debris of the polishing pad adsorbing to the surface of the substrate to be polished.

[0066] The polishing pad protectant of the embodiment can contain sugar alcohol. The pad protectant which is sugar alcohol can adhere to the surface of the pad during the polishing process and can stably protect the pad. Also, since sugar alcohol has the property of being difficult to be utilized as nutrients for bacteria, applying sugar alcohol to the polishing composition can effectively suppress the excessive growth of microorganisms in the composition and effectively suppress the contamination of the device production line by the microorganisms. The sugar alcohol may be any one selected from the group consisting of sorbitol, mannitol, galactitol, fucitol, iditol, inositol, arabitol, xylitol, erythritol, trehalose and combinations thereof. The sugar alcohol may be sorbitol.

[0067] The polishing pad protectant may contain 50% by weight or more of sugar alcohol. The polishing pad protectant may contain 60% by weight or more of sugar alcohol. The polishing pad protectant may contain 70% by weight or more of sugar alcohol. The polishing pad protectant may contain 100% by weight or less of sugar alcohol. The polishing pad protectant may be sugar alcohol.

[0068] The polishing composition for semiconductor processes can contain 1% to 5% by weight of the polishing pad protectant. The polishing composition for semiconductor processes may contain 1.5% by weight or more of the polishing pad protectant. The polishing composition for semiconductor processes may contain 4% by weight or less of the polishing pad protectant. When such a polishing composition is applied to the polishing process, it is possible to suppress the contamination of the surface of the substrate after polishing by organic matter-derived particles.

[0069] Fluorine-based surfactant Embodiments can apply a fluorosurfactant to the polishing composition. The surfactant can adsorb onto the surface of the debris of the polishing pad generated during the polishing process, further enhancing the hydrophilicity of the debris. Through this, it is possible to effectively prevent the debris from adsorbing onto the surface of the surface to be polished. Also, the fluorine groups contained in the fluorosurfactant can assist in killing bacteria and various microorganisms and contribute to reducing the number of defects caused by organic particles detected on the surface to be polished.

[0070] The fluorosurfactant may be a fluoroalkyl alkylene oxide-based compound. The fluorosurfactant may be a compound represented by the following Chemical Formula 1.

[0071] [Chemical Formula]

[0072] In Chemical Formula 1, the R f is a fluoroalkyl group having 3 to 10 carbon atoms, the R en is an alkylene group having 2 or 3 carbon atoms, and n is an integer from 2 to 15.

[0073] In Chemical Formula 1, R f may be a perfluoroalkyl group having 3 to 10 carbon atoms.

[0074] The fluorosurfactant may be a polymeric surfactant. The fluorosurfactant may have a weight average molecular weight of 150 g / mol to 3,000 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 2,500 g / mol or less. The weight average molecular weight may be 2,000 g / mol or less. The weight average molecular weight may be 1,500 g / mol or less.

[0075] The fluorosurfactant having the above characteristics comes to have a regulated main chain length and can efficiently discharge the debris of the polishing pad. Also, through this, an excessive increase in the dispersibility of the polishing composition can be prevented.

[0076] The weight average molecular weight of the polymer surfactant is measured through GPC (Gel Permeation Chromatography).

[0077] In the embodiment, the content of the fluorosurfactant can be adjusted within a preset range. Through this, it is possible to suppress the adhesion of organic particles to the surface to be polished after polishing, and prevent excessive foaming in the polishing composition during the polishing process, thereby preventing a decrease in processability.

[0078] The polishing composition for semiconductor processes may contain 10 ppm (by weight) or more of a fluorosurfactant. The polishing composition for semiconductor processes may contain 20 ppm (by weight) or more of a fluorosurfactant. The polishing composition for semiconductor processes may contain 50 ppm (by weight) or more of a fluorosurfactant. The polishing composition for semiconductor processes may contain 100 ppm (by weight) or more of a fluorosurfactant. The polishing composition for semiconductor processes may contain 150 ppm (by weight) or more of a fluorosurfactant. The polishing composition for semiconductor processes may contain 500 ppm (by weight) or less of a fluorosurfactant. The polishing composition for semiconductor processes may contain 450 ppm (by weight) or less of a fluorosurfactant. In such cases, the hydrophilicity of the debris of the polishing pad can be efficiently increased, and the generation of excessive foam during the polishing process can be suppressed.

[0079] Tungsten inhibitor The polishing composition for semiconductor processes can further contain a tungsten inhibitor.

[0080] Among the surfaces of the substrates to be polished, especially in the case of tungsten films, there is a tendency for organic particles such as bacteria and microorganisms to adsorb more frequently on the surface compared to other thin films. The polishing composition of the embodiment can cause a tungsten inhibitor to adhere to the surface of the tungsten film during the polishing process. The tungsten inhibitor can effectively prevent organic particles from adhering to the tungsten film and suppress excessive corrosion of the tungsten film.

[0081] The tungsten inhibitor may be any one selected from the group consisting of azole compounds, amino acids, and combinations thereof.

[0082] The azole compound is a 5-membered heterocyclic compound containing a nitrogen atom and one or more non-carbon atoms in the ring and / or its derivative.

[0083] The azole compound may 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 combinations thereof.

[0084] 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.

[0085] The polishing composition for semiconductor processes can contain 0.01 wt% to 0.5 wt% of a tungsten inhibitor. The polishing composition for semiconductor processes may contain 0.02 wt% or more of a tungsten inhibitor. The polishing composition for semiconductor processes may contain 0.3 wt% or less of a tungsten inhibitor. The polishing composition for semiconductor processes may contain 0.2 wt% or less of a tungsten inhibitor. The polishing composition for semiconductor processes may contain 0.1 wt% or less of a tungsten inhibitor. In such cases, it is possible to suppress the adsorption of organic foreign substances on the surface of the tungsten film and prevent the corrosion of the tungsten film. Further, it is possible to prevent the pH of the polishing composition from becoming excessively high due to the tungsten inhibitor and suppress the deterioration of the polishing characteristics of the polishing composition with respect to the silicon oxide film.

[0086] Other additives The polishing composition for semiconductor processes can further contain other additives. The additives are not limited as long as they are those commonly applied in the CMP field. Exemplarily, the additives may be at least any one of an oxidizing agent, an acid component, a pH adjuster, a dispersant, a polishing rate improver, a polishing regulator, and a preservative.

[0087] The polishing composition for semiconductor processes can further contain an oxidizing agent. The oxidizing agent plays a role in creating an environment in which the surface of the substrate can be more easily planarized by oxidizing a metal such as tungsten, and improving the polishing rate and the etching rate.

[0088] The oxidizing agent may be at least any 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.

[0089] The polishing composition for semiconductor processes can contain 0.01% to 5% by weight of an oxidizing agent. In such a case, the composition can exhibit excellent polishing characteristics with respect to metals and can suppress the formation of an oxide film on the metal to be polished during the polishing process.

[0090] The polishing composition for semiconductor processes can further contain an acid component. Exemplary acid components include at least any 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, propionic acid, fumaric acid, lactic acid, salicylic acid, pimelic acid, benzoic acid, succinic acid, phthalic acid, butyric acid, glutaric acid, glutamic acid, glycolic acid, aspartic acid, tartaric acid, and salts thereof.

[0091] The polishing composition for semiconductor processes can further contain a pH adjuster together with the acid component. Exemplary pH adjusters include any one selected from the group consisting of ammonia, aminomethylpropanol, tetramethylammonium hydroxide, potassium hydroxide, sodium hydroxide, magnesium hydroxide, rubidium hydroxide, cesium hydroxide, sodium hydrogen carbonate, sodium carbonate, imidazole, and combinations thereof.

[0092] The polishing composition for semiconductor processes can further contain a dispersant.

[0093] The dispersant can prevent aggregation between polishing particles within the polishing composition and disperse them uniformly. A cationic dispersant can increase the zeta potential of the polishing composition positively, and an anionic dispersant can decrease the zeta potential of the polishing composition negatively.

[0094] The dispersant can include anionic low molecules, cationic polymers, organic acids, and the like.

[0095] The anionic low molecules of the dispersant may be one or more selected from oxalic acid, citric acid, polysulfonic acid, polyacrylic acid, polymethacrylic acid, and combinations thereof.

[0096] The cationic polymer of the dispersant may be one or more selected from polylysine, polyethyleneimine, benzethonium chloride, bronidox, cetrimonium bromide, cetrimonium chloride, dimethyldioctadecylammonium chloride, tetramethylammonium hydroxide, distearyldimethylammonium chloride, polyarylamine, and combinations thereof.

[0097] 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.

[0098] The polishing rate improver is an additive for increasing the polishing rate of the substrate or wiring to be polished, and may be one or more selected from potassium nitrate, iron nitrate, ammonium hydroxide, citric acid, acetic acid, and combinations thereof.

[0099] The polishing regulator is for minimizing the adsorption of the polishing composition on the metal surface, and may include an ammonium compound, potassium nitrate, an amino acid, a salt thereof, and the like.

[0100] The polishing composition for semiconductor processes may contain a solvent. The solvent may be water, specifically ultrapure water.

[0101] Polishing characteristics of the polishing composition The polishing rate of the polishing composition for semiconductor processes with respect to the silicon oxide film may be 1000 Å / min or more. The polishing rate may be 1100 Å / min or more. The polishing rate may be 1200 Å / min or more. The polishing rate may be 3000 Å / min or less. The polishing rate may be 2500 Å / min or less. The polishing rate may be 2000 Å / min or less.

[0102] The polishing rate of the polishing composition for semiconductor processes with respect to the tungsten film may be 50 Å / min or more. The polishing rate may be 70 Å / min or more. The polishing rate may be 500 Å / min or less. The polishing rate may be 300 Å / min or less. The polishing rate may be 200 Å / min or less.

[0103] The polishing selectivity of the silicon oxide film with respect to the tungsten film of the polishing composition for semiconductor processes 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.

[0104] In such a case, the polishing composition can exhibit an excellent polishing rate selectivity of the silicon oxide film compared to the polishing rate of tungsten.

[0105] The Ra value of the tungsten film measured after polishing for 30 seconds with the polishing composition for semiconductor processes may be 3 nm or less. The Ra value may be 2 nm or less. In such a case, the polishing composition can provide a polished surface with a smoother surface.

[0106] The Ra value is measured in accordance with ISO 4287.

[0107] The polishing of each thin film is 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. As the polishing pad, the SR-300 model of SK Empulse can be applied.

[0108] When measuring the polishing rate of each thin film, as an example, the AP-300 model of CTS can be applied to the polishing machine.

[0109] Method for manufacturing a substrate The method for manufacturing the substrate of the embodiment includes a process of applying the polishing composition for semiconductor processes as a slurry to polish the substrate.

[0110] The substrate can include at least any one of an insulating film, a metal wiring, and a barrier layer on its upper surface. The metal wiring can include copper or tungsten. When the metal wiring includes copper, the barrier layer can include tantalum and its nitride. When the metal wiring includes tungsten, the barrier layer can include titanium and its nitride.

[0111] Specifically, in the process of polishing the substrate, the substrate to be polished is brought into contact with a polishing composition for semiconductor processes supplied from an injection nozzle on a polishing pad, and while the polishing head fixing the substrate rotates, the surface plate with the polishing pad attached can also rotate.

[0112] The method for manufacturing a substrate can include a process of polishing a tungsten film exposed on the upper surface of the substrate for 5 seconds to 20 seconds through a polishing composition for semiconductor processes (partial CMP).

[0113] The method for manufacturing a substrate can include a process of polishing a tungsten bulk film formed on the upper surface of the substrate through a polishing composition for semiconductor processes to separate nodes.

[0114] The process of polishing the substrate can further include a process of conditioning the surface of the polishing pad before polishing, if necessary.

[0115] The polishing composition for semiconductor processes can polish a wafer in contact with the polishing pad while penetrating toward the substrate.

[0116] In the process of polishing the substrate, a pressure of 6.89 kPa to 48.26 kPa can be applied. The pressure may be 13.79 kPa to 34.47 kPa.

[0117] The process of polishing the substrate may be performed for 50 seconds to 10 minutes. However, it can be changed according to the desired degree of polishing.

[0118] The description of the polishing composition for semiconductor processes is omitted because it overlaps with the above content.

[0119] The method for manufacturing a substrate can further include a cleaning process of cleaning the polished substrate.

[0120] The cleaning process may be performed by cleaning the polished substrate through purified water and an inert gas.

[0121] Hereinafter, specific examples will be described in more detail. The following examples are merely illustrative for helping to understand the present invention, and the scope of the present invention is not limited thereto.

[0122] Production Example: Production of Polishing Composition Example 1: To ultrapure water as a solvent, 3% by weight of colloidal silica surface-modified with 38 ppm (by weight) of (3-aminopropyl)triethoxysilane as polishing particles, 2% by weight of sorbitol as a polishing pad protector, and 50 ppm (by weight) of FS3100 from Capsstone as a fluorine-based surfactant were added and mixed to prepare a polishing composition of a total of 100% by weight.

[0123] Example 2: 0.05% by weight of glycine was additionally applied as a tungsten inhibitor, and a polishing composition of a total of 100% by weight was prepared under the same conditions as in Example 1 except that the average particle size of the polishing particles, the pH, the electrical conductivity, and the zeta potential of the polishing composition were applied as described in Table 1.

[0124] Example 3: A polishing composition of a total of 100% by weight was prepared under the same conditions as in Example 1 except that the average particle size of the polishing particles, the pH, the electrical conductivity, and the zeta potential of the polishing composition were applied as described in Table 1.

[0125] Comparative Example 1: 1% by weight of sorbitol and 2% by weight of sucrose were applied as a polishing pad protectant, and 0.05% by weight of aminotetrazole, 0.05% by weight of glycine, and 0.05% by weight of imidazole were additionally applied as tungsten inhibitors. A polishing composition of 100% by weight was prepared under the same conditions as in Example 1, except that the average particle size of the polishing particles, the pH, the electrical conductivity, and the zeta potential of the polishing composition were applied as described in Table 1.

[0126] Comparative Example 2: 25 ppm (by weight) of a fluorine-based surfactant was applied. A polishing composition of 100% by weight was prepared under the same conditions as in Comparative Example 1, except that the average particle size of the polishing particles, the pH, the electrical conductivity, and the zeta potential of the polishing composition were applied as described in Table 1.

[0127] The content of each component in the polishing compositions of each example and comparative example, and the average particle size (primary particle size) of the polishing particles are described in Table 1 below, and the pH, the electrical conductivity, and the zeta potential of the polishing compositions are described in Table 2 below.

[0128] Evaluation Example: Measurement of the number of defects on the surface to be polished and the polishing rate of the polishing composition The upper surface of a 300-mm diameter wafer was polished with the polishing compositions of each example and comparative example using a CTS AP-300 polishing machine. The wafer used had a tungsten film formed on the entire upper surface with a thickness of 100 Å to 1,000 Å.

[0129] The polishing was performed under the conditions of a polishing time of 60 seconds, 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.

[0130] After the polishing of the wafer was completed, a back-etching process was performed by plasma etching with SF 6 gas for 1 minute.

[0131] After the back-etching was completed, the total number of defects formed on the wafer was measured through defect measurement equipment, and the measured value was designated as the De value.

[0132] After that, out of the measured defects, 100 defects were arbitrarily selected, and then using an in-line SEM (Scanning Electron Microscope), it was confirmed whether the selected defects were defects derived from organic substances, that is, organic particles. The number of defects derived from organic substances among the 100 selected defects was calculated, and the value was defined as the Dm value.

[0133] The Rm / e value was calculated from the De value and the Dm value.

[0134] The measured values and calculated values for each of the above Examples and Comparative Examples were described in Table 3 below.

[0135] Then, from the polished wafer, the height difference of the tungsten film before and after polishing and the height difference of the silicon oxide film were measured, and the polishing rate of the tungsten film and the polishing rate of the silicon oxide film were calculated from the above values.

[0136] The measured values and calculated values for each of the above Examples and Comparative Examples were described in Table 2 below.

[0137] Evaluation Example: Measurement of the wear rate of the pad The height of the polishing pad, which is the SR-300 model of SK Enpulse Co., Ltd., was measured through a profiler. Then, the above polishing pad and polishing compositions for each of the Examples and Comparative Examples were applied, and using an AP-300 polishing machine of CTS Co., Ltd., the tungsten film formed on the upper surface of a 300-mm diameter wafer was continuously polished.

[0138] The polishing was carried out 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 carried out without replacing the polishing pad until the cumulative polishing process time reached 20 hours.

[0139] After finishing the polishing, the height of the polishing pad was measured with a profiler.

[0140] The height difference of the polishing pad before and after polishing was calculated, and the height difference was divided by the polishing time to calculate the wear rate of the pad.

[0141] The calculated values for each of the examples and comparative examples were described in Table 3 below.

[0142] Evaluation Example: Measurement of the amount of bubble generation 3 L of the polishing composition for each of the examples and comparative examples was charged into a glass reactor having a volume of 5 L. The charged polishing composition was stirred at 25 °C at a speed of 1,000 RPM for 30 minutes with a four-blade blade having a total length of 10 cm. After 10 minutes had elapsed since the completion of the stirring, 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.

[0143] The calculated bubble volume values for each of the examples and comparative examples were described in Table 3 below.

[0144] [Table 1]

[0145] [Table 2]

[0146] [Table 3]

[0147] In Table 3 above, in the case of the Rm / e value, Examples 1 to 3 showed values of 1% or less, while Comparative Examples 1 and 2 showed values of 2.5% or more.

[0148] In terms of the wear rate of the pad, the examples showed lower values than the comparative examples.

[0149] In terms of the volume of the bubbles, Examples 1 to 3 showed values of 30 ml or less. This means that, in the case of the embodiments, the degree of bubble generation during the polishing process can be controlled below a certain level.

[0150] Although the preferred embodiments have been described in detail above, the scope of the rights of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concepts of the embodiments defined in the appended claims also belong to the scope of the rights of the present invention.

Claims

1. The polishing pad comprises an abrasive particle, a polishing pad protectant, and a fluorosurfactant, A polishing composition for semiconductor processing, having an Rm / e value, which is the ratio of the number of defects derived from organic matter, as shown in the following formula 1, of 2.5% or less. [Formula 1] (In the above formula 1, The De value is the number of defects detected on the entire upper surface of a substrate after polishing the upper surface of the substrate with the polishing composition for semiconductor processing and etching back the polished upper surface of the substrate, The Dm value is the number of defects that are derived from organic matter among the defects selected when a total of 100 defects are arbitrarily selected from the defects detected on the entire upper surface of the substrate after polishing and etching back.

2. The polishing composition for semiconductor processing according to claim 1 , wherein the polishing pad protective agent comprises a sugar alcohol.

3. 3. The polishing composition for semiconductor processing 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 combinations thereof.

4. The polishing composition for semiconductor processing according to claim 1 , wherein the fluorosurfactant is a fluorosurfactant represented by the following formula 1: 【Chemistry 1】 (In the above Chemical Formula 1, the R ｆ is a fluoroalkyl group having 3 to 10 carbon atoms, ｅｎ is an alkylene group having 2 or 3 carbon atoms, and n is an integer from 2 to 15.

5. 2. The polishing composition for semiconductor processing according to claim 1, comprising 1% by weight to 5% by weight of the polishing pad protective agent.

6. 2. The polishing composition for semiconductor processing according to claim 1, comprising the fluorosurfactant in an amount of 10 ppm (by weight) to 500 ppm (by weight).

7. Further comprising a tungsten inhibitor; The polishing composition for semiconductor processing according to claim 1 , wherein the tungsten inhibitor is any one selected from the group consisting of azole compounds, amino acids, and combinations thereof.

8. 2. The polishing composition for semiconductor processing according to claim 1, having a pH of 2.5 to 5.

9. A method for producing a substrate, comprising a step of polishing a substrate by applying the polishing composition for semiconductor processing according to claim 1 as a slurry.

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