Polishing composition for semiconductor process and polishing method of substrate using the same

Abstract

To provide a polishing composition for a semiconductor process which is applicable to a chemical mechanical polishing (CMP) process to effectively improve polishing process convenience and provide a polished surface with a substantially reduced frequency of defects.SOLUTION: A polishing composition for a semiconductor process includes abrasive particles and a surfactant. A volume of foam measured immediately after stirring 3 L of the polishing composition for a semiconductor process at 25°C at a speed of 1,000 rpm for 30 minutes and letting it stand for 10 minutes is 50 mL or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The embodiments relate to a polishing composition for semiconductor processing and a method for polishing a substrate using the same. [Background technology]

[0002] As semiconductor elements become finer and denser, finer pattern formation techniques are used, which makes the surface structure of the semiconductor elements more complicated and the steps in the interlayer films larger. In manufacturing semiconductor elements, 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 surface of the substrate is polished by applying pressure and rotating the substrate while a slurry is applied to the polishing pad. The object to be planarized varies depending on the process stage, and the properties of the slurry used at this time also vary.

[0004] Polishing after the metal wiring is formed must maintain a sufficient polishing rate and polishing speed while minimizing dishing or erosion. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Korean Patent No. 10-0917955 [Patent Document 2] Korean Patent Publication No. 10-2015-0025969 [Patent Document 3] Korean Patent No. 10-1101207 Summary of the Invention [Problem to be solved by the invention]

[0006] The purpose of the embodiment is to provide a polishing composition for semiconductor processing that, when applied to a CMP process, can effectively improve the convenience of the polishing process and substantially reduce the frequency of defects on the polished surface. [Means for solving the problem]

[0007] A polishing composition for semiconductor processing according to one embodiment of the present specification includes abrasive particles; and a surfactant.

[0008] The polishing composition for semiconductor processing (3 L) is stirred at 25° C. at 1,000 RPM for 30 minutes, and the volume of bubbles measured immediately after leaving the composition for 10 minutes is 50 mL or less.

[0009] The polishing composition for semiconductor processing may have a viscosity at 25°C of 0.7 cP to 1.5 cP.

[0010] The polishing composition for semiconductor processing may have a dynamic surface tension of 25 mN / m to 70 mN / m at a bubble lifetime of 10 seconds.

[0011] The surfactant may include a non-ionic surfactant.

[0012] The nonionic surfactant may include a first nonionic surfactant having an HLB (Hydrophilic-Lipophilic Balance) value of 10 or more.

[0013] The nonionic surfactant may include a second nonionic surfactant having an HLB (Hydrophilic-Lipophilic Balance) value of 8 or less.

[0014] The surfactant may include a polymer surfactant.

[0015] The polymer surfactant may have a weight average molecular weight of 150 g / mol to 3,000 g / mol.

[0016] The polishing composition for semiconductor processing may further include an antifoaming agent.

[0017] The defoaming agent may include a water-soluble polymer.

[0018] The weight average molecular weight of the defoamer may be from 200 g / mol to 2,000 g / mol.

[0019] The antifoaming agent may include a polyglycerin-based compound.

[0020] The polishing composition for semiconductor processing may have a pH of 2-5.

[0021] The abrasive particles may have a positive charge on the surface.

[0022] A method for manufacturing a substrate according to another embodiment of the present specification includes a step of polishing a substrate by applying the polishing composition for semiconductor processing as a slurry. Effect of the Invention

[0023] When the polishing composition for semiconductor processing according to the embodiment is applied to a CMP process, it can effectively improve the convenience of the polishing process and provide a polished surface with a reduced frequency of defect occurrence. BEST MODE FOR CARRYING OUT THEINVENTION

[0024] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is not limited to the embodiments described herein, but may be practiced in various different forms.

[0025] As used herein, terms of degree such as "about," "substantially," and the like are used in a numerical or approximate sense when the tolerances of manufacturing and materials inherent in the referred meaning are given, and are used to prevent unscrupulous infringers from unfairly taking advantage of disclosures in which precise or absolute numerical values ​​are referred to to aid in the understanding of the embodiments.

[0026] Throughout this specification, the term "combinations thereof" in a Markush form phrase means a mixture or combination of one or more selected from the group of elements set forth in the Markush form phrase, including one or more selected from the group of elements.

[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 identical terms from one another, unless otherwise specified.

[0029] In this specification, the term "B is located on A" means that B can be located on A, or B can be located on A with another layer located therebetween, and is not to be interpreted as being limited to B being located in contact with the surface of A.

[0030] In this specification, the term "singular" is to be construed as including the singular or plural as the context requires, unless otherwise specified.

[0031] Hereinafter, the embodiment will be described in detail.

[0032] Physical properties of the polishing composition The polishing composition for semiconductor processing according to the embodiment includes abrasive particles and a surfactant.

[0033] 3 L of the polishing composition for semiconductor processing is stirred at 25°C at 1,000 RPM for 30 minutes, and allowed to stand for 10 minutes. The volume of bubbles measured is 50 mL or less.

[0034] A surfactant may be added to the polishing composition for semiconductor processing in order to adjust the affinity of the polishing composition to the surface to be polished and to suppress the adsorption of abrasive particles and organic particles to the surface to be polished. However, a polishing composition containing a surfactant may form a large number of bubbles during the supply process or polishing process. A large number of bubbles may excessively increase the volume of the polishing composition, which may cause problems during the introduction of the polishing composition, and may cause agglomeration between abrasive particles during the polishing process, which may cause scratches on the surface to be polished.

[0035] The embodiment can effectively improve the convenience of CMP-related processes by controlling bubble-related properties of the polishing composition containing a surfactant, and can effectively suppress the occurrence of defects on the polished surface due to aggregation and adsorption of abrasive particles.

[0036] The method for measuring the volume of bubbles is as follows.

[0037] 3 L of polishing composition for semiconductor processing is added to a glass reactor with a volume of 5 L. The polishing composition is stirred with a 4-blade blade with a total length of 10 cm at a speed of 1,000 RPM at 25° C. for 30 minutes. The blade is a blade that is generally used in the field of stirrers. After 10 minutes have elapsed since the end of stirring, the height of bubbles formed in the glass reactor is measured. The volume of the bubbles is calculated from the height value and the inner diameter of the container containing the polishing composition.

[0038] The volume of bubbles measured after stirring 3 L of the polishing composition for semiconductor processing at 25° C. for 30 minutes at a speed of 1,000 RPM and leaving for 10 minutes may be 50 mL or less. The volume of the bubbles may be 40 mL or less. The volume of the bubbles may be 30 mL or less. The volume of the bubbles may be 1 mL or more. In such a case, the polishing composition can be easily applied to the object to be polished, and can contribute to suppressing aggregation of abrasive particles during the polishing process.

[0039] The polishing composition for semiconductor processing may have a viscosity at 25°C of 0.7 cP to 1.5 cP.

[0040] In the embodiment, adjusting the viscosity of the polishing composition within a preset range in the embodiment can effectively reduce the amount of bubbles generated in the polishing composition containing a surfactant and can help the generated bubbles to disappear quickly. In addition, adjusting the viscosity within a preset range in the embodiment can contribute to the polishing composition having a stable polishing rate for the polished surface for a relatively long period of time.

[0041] The viscosity of the polishing composition is measured via a viscometer.

[0042] The polishing composition for semiconductor processing may have a viscosity of 0.7 cP to 1.5 cP at 25° C. The viscosity may be 0.8 cP or more. The viscosity may be 0.9 cP or more. The viscosity may be 1.3 cP or less. The viscosity may be 1.1 cP or less. This may help prevent excessive foaming during the polishing process while allowing the polishing composition to maintain a stable polishing rate for the surface to be polished.

[0043] The polishing composition for semiconductor processing may have a dynamic surface tension of 25 mN / m to 70 mN / m at a bubble lifetime of 10 seconds.

[0044] The polishing composition of the embodiment may exhibit a relatively controlled dynamic surface tension within a relatively short bubble lifetime. Such a polishing composition may exhibit excellent affinity to the substrate surface and organic particles present on the substrate even when frequent movement occurs due to relative motion between the substrate and the polishing pad. At the same time, it may be useful to suppress excessive generation of bubbles in the polishing composition during the polishing process.

[0045] The dynamic surface tension of the polishing composition is measured by the maximum bubble pressure method using a bubble pressure tensiometer. The maximum bubble pressure method is a method in which the polishing composition to be measured is inserted into a capillary, and the internal pressure of the bubbles formed at the end of the capillary is measured when gas is injected into the capillary, and the dynamic surface tension is calculated from the measured value. In the maximum bubble pressure method, the bubble lifetime refers to the time it takes from when bubbles start to form at the end of the capillary until the internal pressure of the bubbles reaches its maximum.

[0046] When measuring the dynamic surface tension, the time interval is 1 second and the sample volume is 2 mL. For example, the bubble pressure measuring device may be the BPA-1P model manufactured by Sinterface Tech.

[0047] The dynamic surface tension of the polishing composition for semiconductor processing at a bubble lifetime of 10 seconds may be 25 mN / m to 70 mN / m. The dynamic surface tension may be 69 mN / m or less. The dynamic surface tension may be 68 mN / m or less. The dynamic surface tension may be 30 mN / m or more. The dynamic surface tension may be 32 mN / m or more. The dynamic surface tension may be 34 mN / m or more. When the polishing composition having the above characteristics is applied to a CMP process, it can provide a polished surface with improved flatness and stably control the amount of bubbles that may be generated during the polishing process.

[0048] The pH of the polishing composition for semiconductor processing may be 2 to 5. The pH may be 2.5 or more. The pH may be 3.0 or more. The pH may be 4.8 or less. The pH may be 4.6 or less. The pH may be 4.4 or less. The pH may be 4.2 or less. In such cases, the polishing composition can exhibit excellent polishing properties for polished surfaces including silicon oxide films, and can help to stably disperse abrasive particles.

[0049] The pH of the polishing composition for semiconductor processing is measured using a pH meter.

[0050] The zeta potential of the polishing composition for semiconductor processing may be +10 mV to +50 mV. The zeta potential may be +15 mV or more. The zeta potential may be +20 mV or more. The zeta potential may be +45 mV or less.

[0051] The zeta potential of the abrasive particles may be +10 mV to +50 mV. The zeta potential may be +15 mV or more. The zeta potential may be +20 mV or more. The zeta potential may be +45 mV or less.

[0052] The zeta potential of the polishing composition for semiconductor processing and the abrasive particles is measured under the condition that the pH of the polishing composition for semiconductor processing is 2.0 to 5.0.

[0053] In such a case, the polishing composition can exhibit stable dispersibility and excellent polishing properties for a silicon oxide film exhibiting a surface negative charge.

[0054] Composition of the polishing composition abrasive particles The polishing composition can include abrasive particles.

[0055] The abrasive particles can include metal oxide particles and / or silicon oxide particles. The abrasive particles can include silica. The abrasive particles can include colloidal silica.

[0056] The abrasive particles may contain 70% or more by weight of colloidal silica. The abrasive particles may contain 80% or more by weight of colloidal silica. The abrasive particles may contain 90% or more by weight of colloidal silica. The abrasive particles may be colloidal silica.

[0057] The abrasive particles may have a positive charge on the surface. The abrasive particles may be surface-modified so that the surface has a positive charge. The abrasive particles may be surface-modified with a compound having an amine group. The abrasive particles may be surface-modified with an aminosilane.

[0058] The abrasive particles can have a positive charge on the surface when the polishing composition for semiconductor processing has a pH of 2.0 to 5.0.

[0059] The aminosilane may be, 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.

[0060] The polishing composition for semiconductor process may contain 50 ppm (weight basis) to 300 ppm (weight basis) of aminosilane. The polishing composition for semiconductor process may contain 70 ppm (weight basis) or more of aminosilane. The polishing composition for semiconductor process may contain 100 ppm (weight basis) or more of aminosilane. The polishing composition for semiconductor process may contain 120 ppm (weight basis) or more of aminosilane. The polishing composition for semiconductor process may contain 250 ppm (weight basis) or less of aminosilane. The polishing composition for semiconductor process may contain 220 ppm (weight basis) or less of aminosilane. The polishing composition for semiconductor process may contain 200 ppm (weight basis) or less of aminosilane. The polishing composition for semiconductor process may contain 180 ppm (weight basis) or less of aminosilane. In such a case, the polishing composition has a better polishing rate for silicon oxide film, can polish the substrate surface to be polished more smoothly, and can show improved dispersibility. At the same time, it is possible to effectively prevent the generation of residues of the surface modifier and the adsorption of the residues to the surface to be polished.

[0061] The polishing composition for semiconductor processing may contain 1 wt % to 10 wt % of abrasive particles. The polishing composition for semiconductor processing may contain 2 wt % or more of abrasive particles. The polishing composition for semiconductor processing may contain 8 wt % or less of abrasive particles. The polishing composition for semiconductor processing may contain 5 wt % or less of abrasive particles. In such cases, the polishing composition has an excellent polishing rate for the polished surface and can stably suppress aggregation of the abrasive particles.

[0062] The abrasive particles may have an average particle size of 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 for the polished surface, and can stably adjust the frequency of defects occurring on the polished surface.

[0063] The average particle size means the average particle size of the primary particles of the abrasive particles.

[0064] Surfactants The polishing composition for semiconductor processing contains a surfactant, which improves the affinity of the polishing composition for silicon oxide films, thereby allowing the polishing composition to be uniformly distributed on the polished surface during the polishing process.

[0065] The surfactant may be a non-ionic surfactant, which, when attached to the surface of the substrate to be polished with an appropriate strength, can effectively prevent abrasive particles having a positive surface charge from adsorbing to the surface of the substrate to be polished, while being easily removed from the surface of the substrate after polishing.

[0066] The nonionic surfactant may include a first nonionic surfactant having an HLB (Hydrophilic-Lipophilic Balance) value of 10 or greater.

[0067] The HLB value of a nonionic surfactant can be calculated according to the following formula 1.

[0068] JPEG2025063832000001.jpg1832

[0069] In the above formula 1, Mh is the molecular weight of the hydrophilic portion of the nonionic surfactant, and M is the molecular weight of the nonionic surfactant.

[0070] The first nonionic surfactant has relatively high hydrophilicity and can effectively remove organic particles present on the surface of the substrate to be polished.

[0071] The polishing composition for semiconductor process may contain 1 part by weight or more of the first nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 3 parts by weight or more of the first nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 5 parts by weight or more of the first nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 25 parts by weight or less of the first nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 20 parts by weight or less of the first nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 15 parts by weight or less of the first nonionic surfactant per 100 parts by weight of the total nonionic surfactant.

[0072] In such a case, it is possible to effectively prevent abrasive particles, organic matter, etc. from being adsorbed onto the surface of the surface to be polished.

[0073] The nonionic surfactant can include a second nonionic surfactant having an HLB value of 8 or less.

[0074] The second nonionic surfactant has a relatively high lipophilicity and, in addition to the above-mentioned functions, can also function as a defoamer in the polishing composition, which can help to suppress the generation of bubbles in the polishing composition.

[0075] The polishing composition for semiconductor process may contain 20 parts by weight or more of the second nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 25 parts by weight or more of the second nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 30 parts by weight or more of the second nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 35 parts by weight or more of the second nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 75 parts by weight or less of the second nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 70 parts by weight or less of the second nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor process may contain 65 parts by weight or less of the second nonionic surfactant per 100 parts by weight of the total nonionic surfactant. The polishing composition for semiconductor processing may contain up to 60 parts by weight of a second nonionic surfactant per 100 parts by weight of total nonionic surfactant.

[0076] In such a case, it can contribute to effectively reducing the amount of bubbles that are generated while the polishing composition is supplied through piping or participates in polishing.

[0077] The nonionic surfactant may include a first nonionic surfactant and a second nonionic surfactant at the same time, whereby the effects attributable to each of the surfactants described above can be simultaneously imparted to the polishing composition.

[0078] The contents of the first nonionic surfactant and the second nonionic surfactant can be measured by HPLC-MS (High Performance Liquid Chromatography Mass Spectrometer).

[0079] The nonionic surfactant may further include other nonionic surfactants in addition to the first nonionic surfactant and the second nonionic surfactant. Exemplarily, the nonionic surfactant may further include a nonionic surfactant having an HLB value of more than 8 and less than 10.

[0080] The surfactant may include a polymeric surfactant, and the weight average molecular weight of the polymeric surfactant may be 150 g / mol to 3,000 g / mol.

[0081] In the embodiment, a polymeric surfactant having a controlled chain length may be applied to the polishing composition. This can effectively prevent the polishing rate of the polishing composition from decreasing on the polished surface due to the surfactant adsorbed on the polished surface. In addition, it can be useful for adjusting the viscosity of the polishing composition to a stable range.

[0082] The weight average molecular weight of the polymer surfactant is measured by GPC (Gel Permeation Chromatography).

[0083] The polymer 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 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. In this case, the polishing rate of the polishing composition for the silicon oxide film can be stably controlled while effectively improving the affinity of the polishing composition for the silicon oxide film. In addition, when the weight average molecular weight is controlled as above, the generation of excessive bubbles due to an increase in the viscosity of the polishing composition can be effectively suppressed.

[0084] The surfactant may be a fluorosurfactant. The surfactant may be a fluoroalkyl alkylene oxide compound. The surfactant may be a compound according to the following formula 1:

[0085] [C1] R f -(R n -0) x -H

[0086] In the above Chemical Formula 1, R f is a fluoroalkyl group having 3 to 10 carbon atoms, n is an alkylene group having 2 or 3 carbon atoms, and x is an integer of 2 to 15.

[0087] In the above formula 1, R f may be a perfluoroalkyl group having 3 to 10 carbon atoms.

[0088] Exemplary surfactants include triethylene glycol perfluoropentyl ether, triethylene glycol perfluorohexyl ether, triethylene glycol perfluoroheptyl ether, tetraethylene glycol perfluoropentyl ether, tetraethylene glycol perfluorohexyl ether, tetraethylene glycol perfluoroheptyl ether, pentaethylene glycol perfluoropentyl ether, pentaethylene glycol perfluorohexyl ether, pentaethylene glycol perfluoroheptyl ether, hexaethylene glycol perfluoropentyl ether, hexaethylene glycol perfluorohexyl ether, and hexaethylene glycol perfluoroheptyl ether.

[0089] The surfactants having the structure of Chemical Formula 1 may be classified into a first nonionic surfactant or a second nonionic surfactant according to their HLB values. Among the surfactants having the structure of Chemical Formula 1, there may be those that do not fall into the first nonionic surfactant or the second nonionic surfactant according to their HLB values. For example, F-(CF 2 )6 -(CH 2 CH 2 O) 3 In the case of H, the HLB value is about 5.88, which corresponds to the second nonionic surfactant, and F-(CF 2 ) 6 -(CH 2 CH 2 O) 8 In the case of H, the HLB value is about 10.51, which corresponds to the first class of nonionic surfactants.

[0090] The polishing composition for semiconductor process may contain 10 ppm or more of surfactant. The polishing composition for semiconductor process may contain 20 ppm or more of surfactant. The polishing composition for semiconductor process may contain 50 ppm or more of surfactant. The polishing composition for semiconductor process may contain 100 ppm or more of surfactant. The polishing composition for semiconductor process may contain 150 ppm or more of surfactant. The polishing composition for semiconductor process may contain 500 ppm or less of surfactant. The polishing composition for semiconductor process may contain 450 ppm or less of surfactant. In such a case, the affinity of the polishing composition to the surface to be polished can be effectively improved and the generation of excessive bubbles during the polishing process can be suppressed.

[0091] Defoamer The polishing composition for semiconductor processing may further include an antifoaming agent. The antifoaming agent is a material distinct from the surfactant.

[0092] An antifoaming agent is a substance that suppresses the generation of bubbles in the polishing composition when an external force is applied to the polishing composition.

[0093] The antifoaming agent may include a water-soluble polymer, which is uniformly distributed in the polishing composition without excessively increasing the viscosity of the composition and can effectively suppress the generation of bubbles in the polishing composition.

[0094] The water-soluble polymer may include a polyglycerin-based compound.

[0095] The polyglycerin-based compound refers to polyglycerin and its derivatives, and examples of the polyglycerin-based compound include polyglycerin-3, polyglycerin-4, polyglycerin-5, polyglycerin-10, and polyglycerin-20.

[0096] The weight average molecular weight of the water-soluble polymer may be 200 g / mol to 2,000 g / mol. The weight average molecular weight may be 500 g / mol or more. The weight average molecular weight may be 1,500 g / mol or less. The weight average molecular weight may be 1,200 g / mol or less. In this case, it may be possible to effectively suppress the formation of bubbles that may occur during the polishing process, and it may be useful for stably dispersing the abrasive particles.

[0097] The weight average molecular weight of the water-soluble polymer is measured by GPC (Gel Permeation Chromatography).

[0098] The polishing composition for semiconductor process may contain 0.001 wt % or more of an antifoaming agent. The polishing composition for semiconductor process may contain 0.003 wt % or more of an antifoaming agent. The polishing composition for semiconductor process may contain 0.005 wt % or more of an antifoaming agent. The polishing composition for semiconductor process may contain 0.1 wt % or less of an antifoaming agent. The polishing composition for semiconductor process may contain 0.08 wt % or less of an antifoaming agent. The polishing composition for semiconductor process may contain 0.05 wt % or less of an antifoaming agent. The polishing composition for semiconductor process may contain 0.03 wt % or less of an antifoaming agent. In such a case, the generation of bubbles in the polishing composition during the polishing process can be suppressed, effectively improving the convenience of the polishing process.

[0099] Other Additives The polishing composition for semiconductor processing may further include other additives. The additives are not limited as long as they are generally applied in the CMP field. For example, the additives may be at least one of a chelating agent, an oxidizing agent, an acid component, a pH adjusting agent, a dispersing agent, a polishing rate improving agent, a polishing adjusting agent, a polishing pad protecting agent, and a preservative.

[0100] The polishing composition for semiconductor processing may further include a chelating agent. Metals or metal ions removed from the surface of the substrate through the polishing process are likely to reattach or remain on the surface of the substrate, forming defects. In particular, metals such as tungsten may be easily dissolved in the polishing composition under certain conditions, but may have the property of easily adhering to the surface of the object to be polished. The chelating agent is adsorbed to such metals or metal ions, and can easily remove the metals. This can further increase the polishing rate of the polishing composition, and effectively suppress the formation of defects on the substrate surface due to particle reattachment.

[0101] Exemplarily, the chelating agent may be at least one selected from the group consisting of butyric acid, citric acid, tartaric acid, succinic acid, oxalic acid, acetic acid, adipic acid, capric acid, caproic acid, caprylic acid, carboxylic acid, glutaric acid, glutamic acid, glycolic acid, thioglycolic acid, formic acid, mandelic acid, fumaric acid, lactic acid, lauric acid, malic acid, maleic acid, malonic acid, myristic acid, palmitic acid, phthalic acid, isophthalic acid, terephthalic acid, citraconic acid, propionic acid, pyruvic acid, stearic acid, valeric acid, benzoic acid, phenylacetic acid, naphthoic acid, aspartic acid, amino acids, and ethylenediaminetetraacetic acid.

[0102] As the amino acid, glycine, α-alanine, β-alanine, L-aspartic acid, N-methylglycine (methylglycine) or a combination thereof may be applied.

[0103] The chelating agent may contain two or more carboxyl groups or alcohol groups in the molecule. As the chelating agent, two or more types of chelating agents containing two or more carboxyl groups or alcohol groups in the molecule can be applied. Specifically, the chelating agent may include any one selected from the group consisting of EDTA (ethylenediaminetetraacetic acid), glycine, carboxylic acids, and combinations thereof. The carboxylic acids refer to compounds containing at least one or two or more carboxyl groups in the molecule.

[0104] The polishing composition for semiconductor processing may contain 0.003 wt% to 0.5 wt% of a chelating agent. The polishing composition for semiconductor processing may contain 0.005 wt% or more of a chelating agent. The polishing composition for semiconductor processing may contain 0.3 wt% or less of a chelating agent. In such a case, the polishing rate of the polishing composition can be controlled to an appropriate level, and the frequency of occurrence of surface defects of the substrate can be reduced.

[0105] The polishing composition for semiconductor processing may further include an oxidizing agent. The oxidizing agent oxidizes metals such as tungsten to create an environment in which the surface of the substrate can be more easily planarized, and serves to improve the polishing rate and etching rate.

[0106] 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 persulfate, benzoyl peroxide, calcium peroxide, barium peroxide, sodium peroxide, and urea peroxide.

[0107] The polishing composition for semiconductor processing may contain 0.01% by weight to 5% by weight of an oxidizing agent. In this case, the composition can exhibit excellent polishing properties for metals and can suppress the formation of an oxide film on the metal to be polished during the polishing process.

[0108] The polishing composition for semiconductor processing may further include a copper corrosion inhibitor. The copper corrosion inhibitor may include an azole compound.

[0109] The azole compound may illustratively include one selected from the group consisting of benzotriazole (BTA), 5-methyl-1H-benzotriazole (5-MBTA), 3-amino-1,2,4-triazole, 5-phenyl-1H-tetrazole, 3-amino-5-methyl-4H-1,2,4-triazole, 5-aminotetrazole (ATZ), 1,2,4-triazole, tolytriazole, and combinations thereof.

[0110] The azole compound may include one selected from the group consisting of 5-Aminotetrazole (ATZ), 5-Methyl-1H-Benzotriazole (5-MBTA), and combinations thereof.

[0111] The azole-based compound acts on the copper surface during the polishing process and can play a role in preventing copper corrosion.

[0112] The azole-based compound may be included in an amount of 0.02 to 2.00 parts by weight, 0.03 to 1.5 parts by weight, or 0.5 to 1.5 parts by weight based on 100 parts by weight of the abrasive particles.

[0113] When the azole-based compound is contained in such a range, the composition for semiconductor processing can provide a corrosion prevention effect on the copper surface, and in particular, a strong corrosion prevention effect can be provided on a relatively large surface such as the surface of a via hole.

[0114] The polishing composition for semiconductor processing may further include an acid component. The acid component may 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, 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.

[0115] The polishing composition for semiconductor processing may further include a pH adjuster together with the acid component. The pH adjuster may be, for example, 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.

[0116] The polishing composition for semiconductor processing may further contain a dispersant.

[0117] The dispersant can prevent agglomeration between abrasive particles in the polishing composition and disperse them uniformly. The cationic dispersant can increase the zeta potential of the polishing composition to a positive value, and the anionic dispersant can decrease the zeta potential of the polishing composition to a negative value.

[0118] The dispersant may include anionic small molecules, cationic polymers, organic acids, and the like.

[0119] The anionic small molecule of the dispersing agent may be one or more selected from oxalic acid, citric acid, polysulfonic acid, polyacrylic acid, polymethacrylic acid, and combinations thereof.

[0120] The cationic polymer of the dispersing agent 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.

[0121] The organic acid of the dispersing agent may be one or more selected from hydroxylbenzoic acid, ascorbic acid, picolinic acid, glutamic acid, tryptophan, aminobutyric acid, and combinations thereof.

[0122] 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.

[0123] The polishing modifier is intended to minimize the adsorption of the polishing composition to the metal surface, and may include ammonium compounds, potassium nitrate, amino acids, salts thereof, and the like.

[0124] The polishing composition for semiconductor processing may include a solvent, which may be water, specifically ultrapure water.

[0125] Polishing properties of the polishing composition The polishing rate of the polishing composition for semiconductor processing against a 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.

[0126] The polishing rate of the polishing composition for semiconductor processing 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.

[0127] In such a case, the polishing composition can exhibit a superior silicon oxide polishing rate selectivity ratio compared to the tungsten polishing rate.

[0128] The Ra value of the tungsten film measured after polishing with the polishing composition for semiconductor processing for 30 seconds 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 having a smoother surface.

[0129] The Ra value is measured in accordance with ISO 4287.

[0130] Polishing for each thin film is performed under the conditions of pressure 2.2 psi, carrier speed 87 rpm, platen speed 93 rpm, and slurry flow rate 250 ml / min. The polishing pad used is SR-300 model manufactured by SK Empulse.

[0131] When measuring the polishing rate for each thin film, the polishing machine may be, for example, the AP-300 model manufactured by CTS.

[0132] Substrate manufacturing method A method for manufacturing a substrate according to an embodiment includes polishing a substrate by applying a polishing composition for semiconductor processing as a slurry.

[0133] The substrate may include at least one of an insulating film, a metal wiring, and a barrier layer on an 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.

[0134] Specifically, the process of polishing a substrate may be performed by contacting the substrate to be polished with a polishing pad together with a polishing composition for semiconductor processing supplied from a spray nozzle, while the polishing head that fixes the substrate rotates and the platen to which the polishing pad is attached also rotates.

[0135] The process of polishing a substrate can optionally further include conditioning the surface of the polishing pad prior to polishing.

[0136] The polishing composition for semiconductor processing can polish a wafer in contact with the polishing pad while penetrating toward the substrate.

[0137] In the process of polishing the substrate, a pressure of 6.89 kPa to 48.26 kPa may be applied, and the pressure may be 13.79 kPa to 34.47 kPa.

[0138] The process of polishing the substrate may be carried out for 50 seconds to 10 minutes, although this can be varied depending on the desired degree of polishing.

[0139] The description of the polishing composition for semiconductor processing is omitted since it is the same as that described above.

[0140] The method for manufacturing a substrate may further include a cleaning process for cleaning the substrate after polishing.

[0141] The cleaning process may be performed by cleaning the polished substrate with purified water and an inert gas.

[0142] The present invention will be described in more detail with reference to specific examples below. The following examples are merely illustrative to aid in understanding the present invention, and are not intended to limit the scope of the present invention.

[0143] Production Example: Production of Polishing Composition Example 1: A polishing composition of 100 wt % in total was prepared by mixing 3 wt % silica having an average diameter (based on primary particles) of 42 nm, which was surface-modified with (3-aminopropyl)triethoxysilane, and 100 ppm (by weight) of a surfactant into ultrapure water as a solvent. The pH of the polishing composition was adjusted to 4.0.

[0144] The surfactant used was a fluorosurfactant. The surfactant was 100% by weight of the total fluorosurfactant, and F(CF 2 ) 6 -(CH 2 -CH 2 O) 2 H and F(CF 2 ) 6 -(CH 2 -CH 2 O) 3 H28.2% by weight, F(CF 2 ) 6 -(CH 2 -CH 2 O) 4 H20.5% by weight, F(CF 2 ) 6 -(CH 2 -CH 2 O) 5 H19.1% by weight, F(CF 2 ) 6 -(CH 2 -CH 2 O) 6 H14.65% by weight, F(CF 2 ) 6 -(CH 2 -CH 2 O) 7 H9.35% by weight, F(CF 2 ) 6 -(CH 2 -CH 2 O) 8 H4.95% by weight, F(CF 2 ) 6 -(CH 2 -CH 2 O) 9 H2.2% by weight, F(CF 2 ) 6 -(CH 2 -CH 2 O)10 H0.85% by weight, F(CF 2 ) 6 -(CH 2 -CH 2 O) 11 It is a fluorine-based surfactant containing 0.2% by weight of H.

[0145] Example 2: A polishing composition totaling 100% by weight was prepared under the same conditions as in Example 1, except that it further contained 0.01% by weight of polyglycerin having a weight-average molecular weight of 750 g / mol (with ultrapure water excluding the corresponding amount).

[0146] Example 3: A polishing composition was prepared under the same conditions as in Example 1, except that 30 ppm of surfactant was applied, making a total of 100% by weight.

[0147] Comparative Example 1: A polishing composition of 100% by weight in total was prepared under the same conditions as in Example 1, except that no nonionic surfactant was used.

[0148] Comparative Example 2: A polishing composition was prepared under the same conditions as in Example 1, except that 1000 ppm of a nonionic surfactant was used, making the total amount of the polishing composition 100% by weight.

[0149] Comparative Example 3: A polishing composition of 100% by weight was prepared by adding and mixing 2% by weight of non-surface-modified silica having an average diameter (based on primary particles) of 45 nm as abrasive particles and nitric acid as a pH adjuster into ultrapure water as a solvent. The pH of the polishing composition was adjusted to 3.8.

[0150] The content of each component in the polishing composition of each Example and Comparative Example, the zeta potential and viscosity of the polishing composition were as shown in Table 1 below.

[0151] Evaluation example: Measurement of air bubble generation volume 3 L of each polishing composition of the Examples and Comparative Examples was added to a glass reactor having a volume of 5 L. The polishing composition was stirred at 25° C. for 30 minutes at a speed of 1,000 RPM with a 4-blade blade having a total length of 10 cm. After 10 minutes had elapsed since the end of stirring, the height of 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.

[0152] The calculated bubble volumes for the Examples and Comparative Examples are shown in Table 2 below.

[0153] Evaluation example: Measurement of dynamic surface tension of polishing compound The dynamic surface tension of the polishing composition of Example 3 and Comparative Example 1 was measured by the maximum bubble pressure method using a bubble pressure measuring instrument BPA-1P manufactured by Sinterface Tech. When measuring the dynamic surface tension, the time interval was 1 second and the sample volume was 2 mL. The measured dynamic surface tension was measured at a bubble lifetime of 10 seconds.

[0154] The measured values ​​for the Examples and Comparative Examples are shown in Table 2 below.

[0155] Evaluation example: Measurement of removal rate for each thin film The polishing compositions of Examples 1 to 3 and Comparative Examples 1 and 2 were applied as slurries to measure the polishing rates of silicon oxide films and tungsten films formed on wafers with a diameter of 300 mm. The polishing rates of each thin film were measured 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, and the polishing machine used was the AP-300 model manufactured by CTS.

[0156] The measured values ​​of the polishing rate for each thin film for each of the examples and comparative examples are shown in Table 3 below.

[0157] Evaluation example: Measurement of defect density on polished surface The polishing compositions of Examples 1 to 3 and Comparative Examples 1 and 2 were used as slurries to polish silicon oxide films formed on wafers with a diameter of 300 mm. The silicon oxide films were polished under the same conditions as those used in the evaluation example for measuring the polishing rate.

[0158] SiO after polishing 2 The number of defects formed on the surface of the wafer was measured using a wafer defect detector, the AIT-XP+ model from KLA Tencor.

[0159] The measurement results for each of the examples and comparative examples are shown in Table 3 below.

[0160] [Table 1]

[0161] [Table 2]

[0162] [Table 3]

[0163] The amount of air bubbles generated was measured to be 30 mL or less in Examples 1 to 3, whereas it was measured to be 500 mL in Comparative Example 2. In particular, Example 2 in which polyglycerin was used showed an even lower amount of air bubbles generated than Example 1 in which polyglycerin was not used.

[0164] In terms of defect density on the polished surface, the defects per wafer were measured to be 100 or less in the case of Example and Comparative Example 2, whereas the defects per wafer were measured to be more than 850 in the case of Comparative Example 1. This is believed to be because the polishing composition with a controlled contact angle with respect to the silicon oxide film can be uniformly distributed on the polished surface during the polishing process, and the surfactant effectively prevents the adsorption of abrasive particles, organic particles, etc. on the polished surface.

[0165] Although the preferred embodiments have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concepts of the embodiments defined in the appended claims also fall within the scope of the present invention.

Claims

1. A polishing composition for semiconductor processing, comprising: The method includes the steps of: The polishing composition for semiconductor processing, in which 3 L of the polishing composition for semiconductor processing is stirred at 25° C. at a speed of 1,000 RPM for 30 minutes and left to stand for 10 minutes, and the volume of bubbles measured immediately thereafter is 50 mL or less.

2. 2. The polishing composition for semiconductor processing according to claim 1, having a viscosity at 25° C. of 0.7 cP to 1.5 cP.

3. 2. The polishing composition for semiconductor processing according to claim 1, which has a dynamic surface tension of 25 mN / m to 70 mN / m at a bubble lifetime of 10 seconds.

4. The surfactant comprises a nonionic surfactant, 2. The polishing composition for semiconductor processing according to claim 1, wherein the nonionic surfactant comprises a first nonionic surfactant having an HLB (hydrophilic-lipophilic balance) value of 10 or more.

5. The surfactant comprises a nonionic surfactant, 2. The polishing composition for semiconductor processing according to claim 1, wherein the nonionic surfactant comprises a second nonionic surfactant having an HLB (hydrophilic-lipophilic balance) value of 8 or less.

6. The surfactant includes a polymer surfactant, 2. The polishing composition for semiconductor processing according to claim 1, wherein the polymer surfactant has a weight average molecular weight of 150 g / mol to 3,000 g / mol.

7. Further comprising an antifoaming agent, The polishing composition for semiconductor processing according to claim 1 , wherein the antifoaming agent comprises a water-soluble polymer.

8. The polishing composition for semiconductor processing according to claim 7, wherein the weight average molecular weight of the defoaming agent is 200 g / mol to 2,000 g / mol.

9. The polishing composition for semiconductor processing according to claim 7 , wherein the antifoaming agent comprises a polyglycerin-based compound.

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

11. The polishing composition for semiconductor processing according to claim 1 , wherein the abrasive particles have a positive charge on the surface.

12. 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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