Polishing composition for semiconductor processes and method for manufacturing a substrate 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 devices are further miniaturized and densified, even finer patterning techniques are being used, which makes the surface structure of semiconductor devices more complex and the step between interlayer films larger. In manufacturing semiconductor devices, a chemical mechanical polishing (hereinafter referred to as "CMP") process is used as a planarization technique for removing steps in a specific film formed on a substrate.

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

[0004] ​​​​​​​​​​​​​​​​​​​​​​​​​​​​The objective of this 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 problem]

[0007] A polishing composition for semiconductor processes according to one embodiment of this specification comprises polishing particles, a polishing pad protectant, and a fluorine-based surfactant.

[0008] The aforementioned polishing composition for semiconductor processes has an Rm / e value of 2.5% or less, which is the ratio of the number of defects derived from organic matter in the following formula 1.

[0009] [Formula 1] JPEG0007834260000001.jpg1042

[0010] In the above formula 1, the De value is the number of defects detected across the entire upper surface of the substrate after polishing the upper surface of the substrate with the semiconductor process polishing composition and then etch-backing the polished upper surface of the substrate.

[0011] The Dm value is the number of defects that originate from organic matter among the 100 defects arbitrarily selected from the defects detected on the entire upper surface of the substrate after polishing and etch-back.

[0012] The abrasive pad protectant may contain a sugar alcohol.

[0013] The sugar alcohol may be any one selected from the group consisting of sorbitol, mannitol, galactitol, fusitol, 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, R f is a fluoroalkyl group having 3 to 10 carbon atoms, 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% to 5% by weight of the polishing pad protector.

[0018] The polishing composition for semiconductor processes may contain 10 ppm (weight basis) to 500 ppm (weight basis) 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 this 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] The embodiments are described in detail below so that they can be easily implemented by a person with ordinary skill in the art to which the embodiments belong. However, the embodiments can be implemented in a variety of different forms and are not limited to the embodiments described herein.

[0025] Terms of degree used herein, such as “about” and “substantially,” are used in the sense of the numerical value or close to the numerical value when tolerances for manufacture and material inherent to the meaning referred to are presented, and are used to prevent unscrupulous infringers from unfairly exploiting disclosures that refer to precise or absolute numerical values ​​to aid in understanding the specific examples.

[0026] Throughout this specification, the term “these combinations” as used in any expression in Markush form means one or more mixtures or combinations selected from the group of components described in the Markush form, and includes one or more of those components.

[0027] Throughout this specification, the phrase "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 between identical terms unless otherwise specified.

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

[0030] In this specification, unless otherwise specified, singular expressions are interpreted to include singular or plural, as interpreted in the context.

[0031] "~-type compounds" include "~ compounds" and their derivatives.

[0032] Organic particles may form on the polished surface after the polishing and etch-back processes. These particles have the characteristic of remaining on the surface of the polished surface and being sticky, and may have a generally irregular shape. Such organic particles may not be easily removed by general cleaning processes.

[0033] The aforementioned contamination is thought to occur because organic substances remaining on the polished surface after the CMP process do not vaporize during the high-temperature etch-back process and instead adsorb onto the substrate surface.

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

[0035] The following provides a detailed explanation of specific examples.

[0036] The semiconductor process polishing composition described in this example comprises polishing particles, a polishing pad protectant, and a fluorine-based surfactant.

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

[0038] [Formula 1] JPEG0007834260000003.jpg1042

[0039] In the above formula 1, the De value is the number of defects detected across the entire upper surface of the substrate after polishing the upper surface of the substrate with the semiconductor process polishing composition and then etch-backing the polished upper surface of the substrate.

[0040] The Dm value is the number of defects that originate from organic matter among the 100 defects arbitrarily selected from the defects detected on the entire upper surface of the substrate after polishing and etch-back.

[0041] One concrete example is that by adjusting the Rm / e value of the polishing composition to a preset range, it is possible to suppress the deterioration of the electrical properties of elements due to organic materials during the production of elements with fine patterns, thereby more effectively increasing the production yield of elements.

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

[0043] A polishing composition is applied to a substrate, which is a wafer with a diameter of 300 mm, and polished using a polishing machine. The substrate used is one in which a tungsten film with a thickness of 100 Å to 1,000 Å is formed on the entire upper surface.

[0044] Polishing is 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. Examples of polishing machines that can be used include the CTS AP-300 model, the AMAT REFLEXTION_LK model, or the EBARA F_REX300X model.

[0045] Etching back is performed on the polished substrate. Specifically, plasma etching is performed on the upper surface of the substrate with SF6 gas for 1 minute.

[0046] After the etch-back process is complete, the total number of defects formed on the wafer is measured using defect measurement equipment, and the measured value is defined as the De value.

[0047] After etch-back, 100 defects are arbitrarily selected from the measured defects, and an in-line SEM (Scanning Electron Microscope) is used to determine whether or not these defects originate from organic matter. Defects originating from organic matter refer to particles composed of organic matter. The number of organic-derived defects among the selected 100 defects is calculated, and this value is defined as the Dm value.

[0048] The Rm / e value is calculated from the De value and Dm value mentioned above.

[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 property defects in the polishing composition are suppressed, which can contribute to the production of devices with high yield.

[0050] The pH of the polishing composition for semiconductor processes may be 2.5 to 5. The pH may be 3 or higher. The pH may be 3.5 or higher. In such cases, the polishing properties of the polishing composition with respect to the surface to be polished can be improved. This allows for the application of polishing particles with an even lower content 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 abrasive composition is measured using a pH meter.

[0052] The zeta potential of the semiconductor process polishing composition may be +5mV to +50mV. The zeta potential may be +10mV or higher. The zeta potential may be +40mV or lower.

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

[0054] In such cases, the polishing composition can exhibit stable dispersibility and excellent polishing properties for silicon oxide films that exhibit a surface negative charge.

[0055] The electrical conductivity of the polishing composition for semiconductor processes may be 20 μS / cm or higher. The electrical conductivity may be 40 μS / cm or higher. The electrical conductivity may be 70 μS / cm or higher. The electrical conductivity may be 100 μS / cm or higher. The electrical conductivity may be 400 μS / cm or lower. In such cases, the polishing composition may help enable the polishing surface to be polished at an excellent polishing speed.

[0056] Composition of polishing composition abrasive particles Abrasive compositions may contain abrasive particles.

[0057] The abrasive particles may include metal oxide particles and / or silicon oxide particles. The abrasive particles may also include silica. The abrasive particles may also include colloidal silica.

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

[0059] Abrasive particles may have a positive surface charge. Abrasive particles may be surface-modified to have a positive surface charge. Abrasive particles may be surface-modified with a compound having an amine group. Abrasive particles may be surface-modified with an aminosilane.

[0060] The aminosilane may be any one selected from the group consisting, for example, 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 may contain 15 ppm (by weight) to 200 ppm (by weight) of aminosilane. The polishing composition may contain 20 ppm (by weight) or more of aminosilane. The polishing composition may contain 25 ppm (by weight) or more of aminosilane. The polishing composition may contain 30 ppm (by weight) or more of aminosilane. The polishing composition may contain 150 ppm (by weight) or less of aminosilane. The polishing composition may contain 100 ppm (by weight) or less of aminosilane. The polishing composition may contain 70 ppm (by weight) or less of aminosilane. The polishing composition may contain 50 ppm (by weight) or less of aminosilane. In such cases, the polishing composition can exhibit an even better polishing rate against silicon oxide films, a smoother polishing of the substrate surface to be polished, and improved dispersibility. At the same time, residue of the surface modifier is generated, and its adsorption to the polished surface can be effectively suppressed.

[0062] A polishing composition for semiconductor processes may contain 1% to 10% by weight of polishing particles. A polishing composition for semiconductor processes may contain 2% or more by weight of polishing particles. A polishing composition for semiconductor processes may contain 8% or less by weight of polishing particles. A polishing composition for semiconductor processes may contain 5% or less by weight of polishing particles. In such cases, the polishing composition has an excellent polishing rate on the surface to be polished and can stably suppress the aggregation of polishing 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 abrasive composition exhibits excellent polishing efficiency on the surface to be polished, and moreover, the frequency of defects occurring on the surface to be polished can be stably controlled.

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

[0065] Polishing pad protectant The polishing pad protectant in this example can effectively reduce the degree of wear of the polishing pad during the CMP process and contribute to reducing the frequency with which polishing pad debris adheres to the substrate surface being polished.

[0066] The polishing pad protectant in the embodiment may contain a sugar alcohol. The pad protectant, being a sugar alcohol, adheres to the surface of the pad during the polishing process and can stably protect the pad. Furthermore, since sugar alcohols have properties that make them difficult for bacteria to utilize as nutrients, applying a sugar alcohol to the polishing composition can suppress the excessive proliferation of microorganisms in the composition and effectively prevent contamination of the element production line by such microorganisms. The sugar alcohol may be any one selected from the group consisting of sorbitol, mannitol, galactitol, fusitol, iditol, inositol, arabitol, xylitol, erythritol, threitol, and combinations thereof. The sugar alcohol may also be sorbitol.

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

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

[0069] Fluorine-based surfactants One concrete example is the application of a fluorine-based surfactant to the polishing composition. The surfactant can adsorb to the surface of the polishing pad debris generated during the polishing process, further increasing the hydrophilicity of the debris. Through this, it is possible to effectively prevent the debris from adsorbing to the surface of the polished surface. In addition, the fluorine group contained in the fluorine-based surfactant can help kill bacteria and various microorganisms, contributing to a reduction in the number of defects caused by organic particles detected on the polished surface.

[0070] The fluorine-based surfactant may also be a fluoroalkylalkylene oxide compound. The fluorine-based surfactant may also be a compound according to the following chemical formula 1.

[0071] [ka]

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

[0073] In the above chemical formula 1, R f This may be a perfluoroalkyl group having 3 to 10 carbon atoms.

[0074] The fluorine-based surfactant may also be a polymer-based surfactant. The fluorine-based surfactant 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] Fluorine-based surfactants having the characteristics described above have a controlled main chain length, which allows for efficient removal of debris from the polishing pad. Furthermore, this prevents an excessive increase in the dispersibility of the polishing composition.

[0076] The weight-average molecular weight of polymeric surfactants is measured by GPC (Gel Permeation Chromatography).

[0077] In practice, the content of the fluorine-based surfactant can be adjusted within a predetermined range. Through this, it is possible to suppress the adhesion of organic particles to the polished surface after polishing, and to prevent excessive foaming of 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 fluorine-based surfactant. The polishing composition for semiconductor processes may contain 20 ppm (by weight) or more of a fluorine-based surfactant. The polishing composition for semiconductor processes may contain 50 ppm (by weight) or more of a fluorine-based surfactant. The polishing composition for semiconductor processes may contain 100 ppm (by weight) or more of a fluorine-based surfactant. The polishing composition for semiconductor processes may contain 150 ppm (by weight) or more of a fluorine-based surfactant. The polishing composition for semiconductor processes may contain 500 ppm (by weight) or less of a fluorine-based surfactant. The polishing composition for semiconductor processes may contain 450 ppm (by weight) or less of a fluorine-based surfactant. In such cases, the hydrophilicity of the debris on 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 may further contain a tungsten inhibitor.

[0080] Among the substrate surfaces to be polished, tungsten films in particular tend to attract organic particles such as bacteria and microorganisms more frequently than other thin films. The polishing composition of the embodiment can be configured so that a tungsten inhibitor adheres 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] Azole compounds are five-membered heterocyclic compounds containing a nitrogen atom and one or more non-carbon atoms within the ring, and / or derivatives thereof.

[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, derivatives thereof, 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 also be glycine.

[0085] The polishing composition for semiconductor processes may contain 0.01% to 0.5% by weight of tungsten inhibitor. The polishing composition for semiconductor processes may contain 0.02% or more by weight of tungsten inhibitor. The polishing composition for semiconductor processes may contain 0.3% or less by weight of tungsten inhibitor. The polishing composition for semiconductor processes may contain 0.2% or less by weight of tungsten inhibitor. The polishing composition for semiconductor processes may contain 0.1% or less by weight of tungsten inhibitor. In such cases, it is possible to suppress the adsorption of organic foreign matter onto the surface of the tungsten film and to prevent corrosion of the tungsten film. Furthermore, it is possible to prevent the pH of the polishing composition from becoming excessively high due to the tungsten inhibitor, thereby suppressing a decrease in the polishing properties of the polishing composition against silicon oxide films.

[0086] Other additives Polishing compositions for semiconductor processes may further contain other additives. The additives are not limited as long as they are commonly used in the field of CMP. Exemplarily, the additives may be at least one of the following: oxidizing agents, acidic components, pH adjusters, dispersants, polishing rate enhancers, polishing modifiers, and preservatives.

[0087] Polishing compositions for semiconductor processes may further contain an oxidizing agent. The oxidizing agent plays a role in improving polishing and etching speeds by creating an environment in which the substrate surface can be flattened more easily by oxidizing metals such as tungsten.

[0088] The oxidizing agent may 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 sulfate peroxide, benzoyl peroxide, calcium peroxide, barium peroxide, sodium peroxide, and urea peroxide.

[0089] Polishing compositions for semiconductor processes may contain 0.01% to 5% by weight of an oxidizing agent. In such cases, the composition can exhibit excellent polishing properties for metals and can suppress the formation of oxide films on the metal being polished during the polishing process.

[0090] The polishing composition for semiconductor processes may further contain an acid component. The acid component may be at least one selected from the group consisting of hydrochloric acid, phosphoric acid, sulfuric acid, hydrofluoric acid, bromate, 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, as an example.

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

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

[0093] Dispersants can prevent aggregation between abrasive particles within the abrasive composition and allow for uniform dispersion. Cationic dispersants can increase the zeta potential of the abrasive composition positively, while anionic dispersants can decrease the zeta potential of the abrasive composition negatively.

[0094] Dispersants may include anionic low molecular weight molecules, cationic polymer molecules, organic acids, etc.

[0095] 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.

[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 dispersant organic acid may be one or more selected from hydroxylbenzoic acid, ascorbic acid, picolinic acid, glutamic acid, tryptophan, aminobutyric acid, and combinations thereof.

[0098] The polishing rate enhancer 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 modifier is intended to minimize the adsorption of the polishing composition onto the metal surface and may include ammonium compounds, potassium nitrate, amino acids, and their salts.

[0100] Polishing compositions for semiconductor processes may contain a solvent. The solvent may be water, and more specifically, ultrapure water.

[0101] Polishing properties of polishing compositions The polishing rate of the semiconductor process polishing composition against 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 semiconductor process polishing composition against a 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 ratio of the silicon oxide film to the tungsten film in the semiconductor process polishing composition may be 5 or more. The polishing selectivity ratio may be 6 or more. The polishing selectivity ratio may be 7 or more. The polishing selectivity ratio may be 20 or less.

[0104] In such cases, the abrasive composition can exhibit a superior selectivity ratio for the abrasive rate of silicon oxide films compared to the abrasive rate of tungsten.

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

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

[0107] Polishing of each thin film is performed under the following conditions: pressure 2.2 psi, carrier speed 87 rpm, platen speed 93 rpm, and slurry flow rate 250 ml / min. SK Empulse's SR-300 model polishing pad can be used.

[0108] When measuring the polishing rate for each thin film, a polishing machine such as the CTS AP-300 model can be used as an example.

[0109] Substrate manufacturing method The manufacturing method of the substrate in the embodiment includes a step of polishing the substrate by applying a semiconductor process polishing composition as a slurry.

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

[0111] Specifically, the process of polishing a substrate involves bringing the substrate to be polished into contact with a polishing pad together with a semiconductor process polishing composition supplied from a spray nozzle. This process can be carried out while the polishing head that holds the substrate in place rotates, and the platen to which the polishing pad is attached also rotates.

[0112] A method for manufacturing a substrate may include a step of polishing the tungsten film exposed on the upper surface of the substrate for 5 to 20 seconds using a semiconductor process polishing composition (partial CMP).

[0113] A method for manufacturing a substrate may include a step of separating nodes by polishing a tungsten bulk film formed on the upper surface of the substrate using a semiconductor process polishing composition.

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

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

[0116] During the process of polishing the substrate, a pressure of 6.89 kPa to 48.26 kPa may be applied. The aforementioned pressure may also be between 13.79 kPa and 34.47 kPa.

[0117] The process of polishing the substrate may be carried out for 50 seconds to 10 minutes. However, this can be adjusted depending on the desired degree of polishing.

[0118] The description of the aforementioned polishing composition for semiconductor processes will be omitted as it will be redundant with the content described above.

[0119] The method for manufacturing the substrate may further include a cleaning process for cleaning the substrate after polishing.

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

[0121] The following describes specific examples in more detail. The following examples are merely illustrative to aid in understanding the present invention, and the scope of the present invention is not limited thereto.

[0122] Manufacturing example: Manufacturing of abrasive compositions Example 1: A polishing composition totaling 100% by weight was prepared by adding and mixing 3% by weight of colloidal silica surface-modified with 38 ppm (by weight) (3-aminopropyl)triethoxysilane as abrasive particles, 2% by weight of sorbitol as a polishing pad protectant, and 50 ppm (by weight) of Capstone's FS3100 as a fluorine-based surfactant to ultrapure water as a solvent.

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

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

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

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

[0127] 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 shown in Table 1 below, and the pH, electrical conductivity, and zeta potential of the polishing composition are shown in Table 2 below.

[0128] Evaluation example: Measurement of the number of defects on the polished surface and the polishing speed of the polishing composition. The polishing compositions for each example and comparative example were applied to the top surface of a 300 mm diameter wafer using a CTS AP-300 polishing machine. The wafers used were those in which a tungsten film with a thickness of 100 Å to 1,000 Å was formed across the entire top surface.

[0129] 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.

[0130] After polishing, an etch-back process was performed on the wafer, involving plasma etching with SF6 gas for 1 minute.

[0131] After the etch-back process was completed, the total number of defects formed on the wafer was measured using defect measurement equipment, and the measured value was defined as the De value.

[0132] Subsequently, 100 defects were arbitrarily selected from the measured defects, and an in-line SEM (Scanning Electron Microscope) was used to confirm whether the selected defects originated from organic matter, i.e., organic particles. The number of organic defects among the 100 selected defects was calculated, and this value was defined as the Dm value.

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

[0134] The measured values ​​and calculated values ​​for each of the above examples and comparative examples are shown in Table 3 below.

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

[0136] The measured values ​​and calculated values ​​for each of the above examples and comparative examples are shown in Table 2 below.

[0137] Evaluation example: Measuring the wear rate of the brake pads. The height of the polishing pad, an SR-300 model from SK Empulse, was measured using a profiler. Subsequently, the polishing pad and polishing compositions for each example and comparative example were applied, and a tungsten film formed on the upper surface of a 300 mm diameter wafer was continuously polished using a CTS AP-300 polishing machine.

[0138] Polishing was performed under the following conditions: pressure 2.2 psi, carrier speed 93 rpm, platen speed 87 rpm, and slurry flow rate 300 ml / min. During polishing, the CMP process was carried out without changing the polishing pad until the cumulative polishing time reached 20 hours.

[0139] After polishing was complete, the height of the polishing pad was measured using a profiler.

[0140] The difference in height of the polishing pad before and after polishing was calculated, and the pad's wear rate was calculated by dividing the height difference by the polishing time.

[0141] The calculated values ​​for each example and comparative example are shown in Table 3 below.

[0142] Evaluation example: Measurement of bubble generation amount Three liters of each polishing composition for the examples and comparative examples were placed in a 5-liter glass reactor. The polishing compositions were stirred with a 10 cm long, four-blade stirring device at 25°C at a speed of 1,000 RPM for 30 minutes. Ten minutes after the end of stirring, the height of the bubbles formed in the glass reactor was measured. The volume of the bubbles was calculated from the height and the inner diameter of the glass reactor containing the polishing compositions.

[0143] The calculated bubble volume values ​​for each example and comparative example are shown in Table 3 below.

[0144] [Table 1]

[0145] [Table 2]

[0146] [Table 3]

[0147] In Table 3 above, when it comes to 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 pad wear rate, the example showed a lower value than the comparative example.

[0149] In terms of bubble volume, Examples 1-3 showed values ​​of 30 ml or less. This means that, in these examples, the degree to which bubbles are generated during the polishing process can be controlled to a certain level or lower.

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

Claims

1. It contains abrasive particles, abrasive pad protectants, and fluorine-based surfactants. The abrasive pad protectant is sorbitol. The fluorine-based surfactant is a fluorine-based surfactant having the following chemical formula 1, The aforementioned fluorine-based surfactant is contained in an amount of 50 ppm (by weight) to 500 ppm (by weight), A polishing composition for semiconductor processes, wherein the Rm / e value, which is the ratio of the number of defects derived from organic matter in the following formula 1, is 2.5% or less. [Case 1] R f -(R en -O) n -H [Formula 1] (In the above chemical formula 1, R f is a fluoroalkyl group having 3 to 10 carbon atoms, R en is an alkylene group having 2 or 3 carbon atoms, and n is an integer from 2 to 15.) In the above formula 1, The De value is the number of defects detected across the entire upper surface of a 300 mm diameter substrate, on which a tungsten film of 100 Å to 1,000 Å thickness has been formed using the semiconductor process polishing composition, under the conditions of polishing time of 60 seconds, pressure of 2.2 psi, carrier speed of 93 rpm, platen speed of 87 rpm, and slurry flow rate of 300 ml / min, followed by plasma etching back of the polished upper surface of the substrate with SF6 gas for 1 minute. The Dm value is the number of defects that originate from organic matter among the 100 defects arbitrarily selected from the defects detected on the entire upper surface of the substrate after polishing and etch-back.

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

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

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

5. A method for manufacturing a substrate, comprising the step of polishing a substrate by applying the semiconductor process polishing composition described in claim 1 as a slurry.

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