Polishing composition for semiconductor processing, manufacturing method of polishing composition, and manufacturing method of semiconductor element using polishing composition

Abstract

The present invention relates to a polishing composition for semiconductor processing and a method for manufacturing semiconductor devices using the polishing composition, which is applicable to the CMP process of an amorphous carbon layer and exhibits a high polishing rate, prevents re-adsorption of carbon residue to a semiconductor substrate during the CMP process and contamination of a polishing pad, and stabilizes an accelerator in the polishing composition, thereby providing a manufacturing method with excellent storage stability. The present invention also provides a method for manufacturing semiconductor devices using the polishing composition for semiconductor processing.

Description

[Technical field]

[0001] The present invention relates to a polishing composition for semiconductor processing, a method for producing the polishing composition, and a method for producing a semiconductor element using the polishing composition. [Background technology]

[0002] As semiconductor elements become finer and denser, finer pattern formation techniques are being 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 a substrate is polished by applying pressure and rotating it while a slurry is applied to a polishing pad. The object to be planarized differs depending on the process step, and the physical properties of the slurry used in this case also differ.

[0004] Specifically, the CMP process has not only been applied to planarizing dielectric materials such as silicon oxide (SiO2) and silicon nitride (SiN), but is also essential for planarizing metal wiring such as tungsten (W) and copper (Cu).

[0005] 2. Description of the Related Art As semiconductor devices become more highly integrated, there is a demand for finer pattern formation and multi-layered circuits.

[0006] For this reason, a variety of films made of different materials with different etching selectivity characteristics are required. Among the various films made of different materials, a carbon-based organic film has a good etching selectivity characteristic compared to other silicon-containing films and can be used as a mask film or a sacrificial film.

[0007] In semiconductor manufacturing processes, organic films are required to be removed by a chemical mechanical polishing process, but no polishing composition capable of efficiently polishing organic films used in semiconductor manufacturing processes by applying a CMP process has been developed.

[0008] There is a need to develop a polishing composition for semiconductor processing that can solve the above problems. Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide a polishing composition for semiconductor processing, a method for producing the polishing composition, and a method for producing a semiconductor element using the polishing composition.

[0010] Another object of the present invention is to provide a polishing composition for semiconductor processing, which is supplied in a polishing process of an amorphous carbon layer, has an excellent polishing rate for the amorphous carbon layer, and prevents carbon residue from being adsorbed on a substrate, thereby preventing the occurrence of defects.

[0011] Another object of the present invention is to provide a method for producing a polishing composition having improved storage stability by stabilizing the accelerator in the polishing composition.

[0012] Another object of the present invention is to provide a method for manufacturing a semiconductor device using a polishing composition for semiconductor processing.

[0013] [Means for solving the problem]

[0014] In order to achieve the above object, a polishing composition for semiconductor processing according to one embodiment of the present invention contains abrasive particles and a surfactant, and has a value of 0.5 to 2 according to the following formula 1:

[0015] [Formula 1] JPEG0007653511000001.jpg1639, where When an amorphous carbon layer (ACL) having a thickness of 2,000 Å was polished for 60 seconds at 2 psi, a carrier speed of 87 rpm, a platen speed of 93 rpm, and an inflow rate of the polishing composition of 200 ml / min, The Ra is a measured polishing rate; The above S is the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles.

[0016] Another embodiment of the present invention relates to a method for producing a polishing composition for semiconductor processing, and includes the steps of mixing a stabilizer and an accelerator in a solvent to prepare a polishing solution, mixing a pH adjuster into the polishing solution to adjust the pH of the polishing solution, and mixing a surfactant and abrasive particles into the pH-adjusted polishing solution.

[0017] A method for manufacturing a semiconductor element according to another embodiment of the present invention includes the steps of: 1) providing a polishing pad including a polishing layer; 2) supplying a polishing composition for semiconductor processing to the polishing pad; and 3) polishing an object to be polished while rotating the polishing pad relative to the polishing surface of the polishing layer so that the surface to be polished of the object to be polished abuts against the polishing surface of the polishing layer, the polishing composition including abrasive particles and a surfactant. Effect of the Invention

[0018] The present invention is applied to the CMP process of an amorphous carbon layer, and has excellent polishing rate, can prevent carbon residue generated during the polishing process from being adsorbed on a semiconductor substrate and from contaminating a polishing pad, and has excellent storage stability.

[0019] It is also possible to provide a method for manufacturing a semiconductor device using the polishing composition for semiconductor processing. [Brief description of the drawings]

[0020] [Figure 1]1 is a schematic diagram of a semiconductor device manufacturing process according to an embodiment of the present invention; [Diagram 2] 4 is a result of a surface tension measurement according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] The present invention relates to a polishing composition for semiconductor processing, which contains abrasive particles and a surfactant, and has a value of 0.5 to 2 according to the following formula 1:

[0022] [Formula 1] JPEG0007653511000002.jpg1639, where When an amorphous carbon layer (ACL) having a thickness of 2,000 Å was polished for 60 seconds at 2 psi, a carrier speed of 87 rpm, a platen speed of 93 rpm, and an inflow rate of the polishing composition of 200 ml / min, The Ra is a measured polishing rate; The above S is the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles. EXAMPLES

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, in which: FIG. 1 is a block diagram of a semiconductor memory device according to an embodiment of the present invention;

[0024] In this specification, when a certain component "includes" another component, this means that the other component may be further included, not excluding the other component, unless otherwise specified.

[0025] In this specification, when a certain component is said to be "connected" to another component, this includes not only the case where the component is "directly connected" but also the case where the component is "connected via another component in between."

[0026] In this specification, the term "B is located on A" means that B is located on A in direct contact with A, or that B is located on A with another layer therebetween, and is not to be interpreted as being limited to B being located in contact with the surface of A.

[0027] As used herein, the term "combinations thereof" contained in a Markush form expression means a mixture or combination of one or more selected from the group of components set forth in the Markush form expression, and is meant to include one or more selected from the group of components.

[0028] In this specification, the phrase "A and / or B" means "A, B, or A and B."

[0029] In this specification, terms such as "first", "second" or "A", "B" are used to distinguish identical terms from each other, unless otherwise specified.

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

[0031] The present invention will now be described in more detail.

[0032] As semiconductor devices become finer and denser, their surface structures become more complex. The surface structure becomes more complex, which means that the semiconductor line width becomes narrower, and the aspect ratio (ratio of length to width) also increases. In order to accommodate the increasing aspect ratio, the photoresist becomes thinner.

[0033] However, the thin and long photoresist cannot withstand the etching process and crumbles, so to prevent this, a hardmask process was introduced.

[0034] Amorphous carbon and SiON were used as the hard mask materials.

[0035] Although the amorphous carbon has excellent etching resistance when used for a hard mask, when a chemical mechanical polishing process is applied using a conventional polishing composition, the polishing rate is low and carbon residue is generated, and the carbon residue is adsorbed on the film surface, causing defects in the semiconductor substrate.

[0036] The polishing composition for semiconductor processing of the present invention has a superior polishing rate for the amorphous carbon film compared to conventional polishing compositions, and can prevent carbon residues from being adsorbed on the film surface, thereby preventing defects in the semiconductor substrate.

[0037] Specifically, the polishing composition for semiconductor processing of the present invention contains abrasive particles and a surfactant, and has a value of 0.5 to 2 according to the following formula 1:

[0038] [Formula 1] JPEG0007653511000003.jpg1639 Where: When an amorphous carbon layer (ACL) having a thickness of 2,000 Å was polished for 60 seconds at 2 psi, a carrier speed of 87 rpm, a platen speed of 93 rpm, and an inflow rate of the polishing composition of 200 ml / min, The Ra is a measured polishing rate; The above S is the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles.

[0039] The polishing composition for semiconductor processing of the present invention includes abrasive particles and a surfactant, and has an excellent polishing rate in the polishing process for the amorphous carbon film and can reduce surface tension to prevent re-adsorption of carbon residues onto the semiconductor substrate.

[0040] More specifically, conventional polishing compositions have a low polishing rate for an amorphous carbon film, and therefore, when used in a polishing process, the polishing time is long and the polishing efficiency is low.

[0041] In order to increase the polishing rate of the amorphous carbon film, a method of increasing the polishing rate of the amorphous carbon film by adding an accelerator to the polishing composition has been proposed. The polishing rate of the amorphous carbon film is increased by adding an accelerator to the polishing composition, but carbon residues generated during the polishing process are re-adsorbed onto the semiconductor substrate, increasing the occurrence of defects on the semiconductor substrate.

[0042] In order to solve the problem of the occurrence of defects, the polishing composition for semiconductor processing of the present invention contains a surfactant to reduce the surface tension of the polishing composition. By containing the surfactant as described above, carbon residues generated during the polishing process can be prevented from being re-adsorbed onto the surface of the semiconductor substrate, thereby preventing the occurrence of defects on the semiconductor substrate.

[0043] The polishing composition used in the semiconductor manufacturing process has a polishing rate of 200 Å / min, preferably 200 Å / min to 300 Å / min, and more preferably 210 Å / min to 250 Å / min, but is not limited to the above examples. When a polishing process for an amorphous carbon film is performed within the scope of the present invention, it can be provided as a highly efficient polishing composition.

[0044] The following Equation 1 relates to the relationship between the polishing rate, abrasive particles, and surfactant for the polishing composition of the present invention:

[0045] [Formula 1] JPEG0007653511000004.jpg1639, where When an amorphous carbon layer (ACL) having a thickness of 2,000 Å was polished for 60 seconds at 2 psi, a carrier speed of 87 rpm, a platen speed of 93 rpm, and an inflow rate of the polishing composition of 200 ml / min, The Ra is a measured polishing rate; The above S is the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles.

[0046] Specifically, when the value of the formula 1 is 0.5 to 2, and preferably 0.7 to 1.4, and falls within the range of the present invention, the polishing rate of the amorphous carbon film can be increased and surface defects of the semiconductor substrate can be prevented.

[0047] In the relationship of Equation 1, the value of the denominator relates to the content of abrasive particles and surfactant, which is present in small amounts in the polishing composition to reduce the surface tension of the polishing composition.

[0048] Specifically, the value of 100 in the denominator means 100 parts by weight, which is the range of the content of the abrasive particles. Also, in the value of the denominator, S in 100S means the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles, and the value of 100 is a coefficient for reflecting the effect of suppressing the occurrence of surface defects on the semiconductor substrate during the polishing process using the surfactant.

[0049] When the value of the formula 1 is within the range of the present invention, the polishing rate of the amorphous carbon film is excellent, and the carbon residue is prevented from being re-adsorbed onto the surface of the semiconductor substrate during the polishing process, thereby suppressing the occurrence of defects in the semiconductor substrate.

[0050] The polishing composition contains 0.5 to 5 parts by weight, preferably 0.5 to 3 parts by weight, of a surfactant per 100 parts by weight of metal oxide particles. When mixed and used within the above range, the value according to formula 1 falls within the range of the present invention, and the polishing composition has an excellent polishing rate for the amorphous carbon film and can prevent carbon residue from being re-adsorbed onto the surface of the semiconductor substrate during the polishing process, thereby suppressing the occurrence of defects in the semiconductor substrate.

[0051] The surfactant is not particularly limited as long as it prevents carbon residue from being re-adsorbed onto the surface of the semiconductor substrate during the polishing process.

[0052] Specifically, the surfactant may include a nonionic fluorine-based polymer compound. The surfactant includes a fluorine-based polymer compound, and when used in a polishing process for an amorphous carbon film, the surfactant can prevent carbon residues generated from being re-adsorbed onto the surface of a semiconductor substrate. In addition, the surfactant includes fluorine, and can inhibit the proliferation of microorganisms such as bacteria and mold. When the polishing composition is stored for a long period of time, bacteria and mold may be generated, and the polishing composition in which bacteria and mold have been generated cannot be used in a polishing process and must be discarded. The polishing composition of the present invention includes a nonionic fluorine-based polymer compound as the surfactant, and can prevent the generation of bacteria and mold when the polishing composition is stored for a long period of time, thereby improving the long-term storage stability.

[0053] The surfactant of the present invention is specifically, tm The polishing agent may be selected from the group consisting of FS-30, FS-31, FS-34, ET-3015, ET-3150, ET-3050, and mixtures thereof, but is not particularly limited thereto as long as it serves to prevent a phenomenon in which carbon residues are re-adsorbed onto the surface of the semiconductor substrate during the polishing process.

[0054] The surfactant of the present invention is a nonionic surfactant, and a surfactant containing a nonionic fluorine-based polymer compound may be used alone or in combination with other nonionic surfactants.

[0055] The nonionic surfactants include polyethylene glycol, polypropylene glycol, polyethylene-propylene copolymer, polyalkyl oxide, polyoxyethylene oxide (PEO), polyethylene oxide, and polypropylene oxide. The fluorosurfactants include sodium sulfonate fluorosurfactant, phosphate ester fluorosurfactant, amine oxide fluorosurfactant, betaine fluorosurfactant, ammonium carboxylate fluorosurfactant, stearate ester fluorosurfactant, quaternary ammonium fluorosurfactant, ethylene oxide / propylene oxide fluorosurfactant, and polyoxyethylene fluorosurfactant. fluorosurfactants).

[0056] The abrasive particles are abrasive particles applicable to polishing compositions for semiconductor processing, and are, for example, selected from the group consisting of metal oxides, organic particles, organic-inorganic composite particles, and mixtures thereof. The metal oxides may be selected from the group consisting of colloidal silica, fumed silica, ceria, alumina, titania, zirconia, zeolite, and mixtures thereof, but are not limited to the above examples, and all abrasive particles that can be selected by a conventional technician can be used without any restrictions.

[0057] The organic particles include polystyrene, styrene copolymers, poly(meth)acrylate, (meth)acrylate copolymers, polyvinyl chloride, polyamide, polycarbonate, polyimide polymers; or particles having a core / shell structure in which the polymer constitutes the core, the shell, or both, and these can be used alone or in combination. The organic particles can be produced by emulsion polymerization, suspension polymerization, or the like.

[0058] The abrasive particles of the present invention may specifically be selected from the group consisting of colloidal silica, fumed silica, ceria, and mixtures thereof.

[0059] The abrasive particles have a diameter (D 50 ) is 10 nm to 120 nm, and preferably, the diameter (D 50 ) is 20 nm to 100 nm, and more preferably, the diameter (D 50 The diameter (D 50 ) is within the above range, defects such as scratches on the substrate to be polished can be reduced and the dispersibility of the abrasive particles can be improved. Specifically, when abrasive particles within the above diameter range are used, the dispersibility of the particles can be improved to prevent clumping between particles in the polishing composition, and the occurrence of defects such as scratches due to the abrasive particles can be prevented.

[0060] The polishing composition can additionally contain an accelerator, a stabilizer, and a pH adjuster.

[0061] The accelerator may be selected from the group consisting of anionic low molecular weight compounds, anionic high molecular weight compounds, hydroxyl acids, amino acids, and cerium salts. Specifically, the cerium salt may be a trivalent cerium salt or a tetravalent cerium salt. More specifically, the tetravalent cerium salt may be selected from the group consisting of cerium (IV) sulfate (Ce(SO4)2), ammonium cerium sulfate dihydrate, and cerium ammonium nitrate, but is not limited to these examples.

[0062] The accelerator is included in the polishing composition to oxidize the surface layer of the amorphous carbon film into oxides or ions, thereby facilitating removal of the surface layer of the amorphous carbon film.

[0063] In addition, the organic film material residues present on the polishing stop layer can be easily removed, which is advantageous in that more uniform polishing can be achieved.

[0064] The cerium ammonium nitrate may be present in the slurry composition in the form of an ionic compound or a chelate compound, and when used in this form, it can provide a high polishing rate for an amorphous carbon film.

[0065] The polishing composition of the present invention contains an accelerator and a stabilizer to increase the polishing rate for the amorphous carbon film. The accelerator not only enables a high polishing rate for the amorphous carbon film, but also enables long-term storage by the stabilizer, and prevents surface defects of the semiconductor substrate caused by re-adsorption of carbon residues onto the semiconductor substrate during the polishing process.

[0066] Therefore, the present invention includes an accelerator and a stabilizer, and the accelerator can increase the polishing rate of the amorphous carbon film, and the stabilizer can increase the stability of the polishing composition and prevent carbon residues from being re-adsorbed onto the semiconductor substrate during the polishing process, thereby preventing the occurrence of defects.

[0067] Specifically, the stabilizer is an amino acid, and more specifically, the amino acid may be selected from the group consisting of arginine, histidine, lysine, aspartic acid, glutamic acid, glutamine, cysteine, proline, asparagine, threonine, alanine, glycine, valine, leucine, isoleucine, and mixtures thereof, and is preferably alanine. However, the stabilizer is not limited to the above examples, and any amino acid that can be mixed with an accelerator to increase the stability of the polishing composition and suppress the occurrence of defects during the polishing process can be used without limitation.

[0068] The pH adjuster may be at least one selected from the group consisting of hydrochloric acid, phosphoric acid, sulfuric acid, hydrofluoric acid, nitric acid, bromic acid, iodic acid, formic acid, malonic acid, maleic acid, oxalic acid, acetic acid, adipic acid, citric acid, adipic acid, acetic acid, propionic acid, fumaric acid, lactic acid, salicylic acid, pimeline, benzoic acid, succinic acid, phthalic acid, butyric acid, glutaric acid, glutamic acid, glycolic acid, lactic acid, aspartic acid, tartaric acid, and potassium hydroxide.

[0069] The pH adjuster can adjust the pH of the polishing composition for semiconductor processing to 2 to 5, preferably 2 to 4. When the acidic environment is maintained within this range, excessive corrosion of metal components and polishing equipment can be prevented, while the polishing rate and quality can be maintained at a certain level or higher.

[0070] The accelerator can be used in an amount of 400 parts by weight to 800 parts by weight based on 100 parts by weight of the abrasive particles in the polishing composition. Specifically, the accelerator can be used in an amount of 450 parts by weight to 700 parts by weight, for example, 450 parts by weight to 550 parts by weight based on 100 parts by weight of the abrasive particles in the polishing composition.

[0071] The stabilizer can be used in an amount of 350 parts by weight to 750 parts by weight based on 100 parts by weight of the abrasive particles in the polishing composition. Specifically, the stabilizer can be used in an amount of 400 parts by weight to 600 parts by weight, for example, 430 parts by weight to 500 parts by weight based on 100 parts by weight of the abrasive particles in the polishing composition.

[0072] The surfactant can be used in an amount of 0.4 to 5 parts by weight based on 100 parts by weight of the abrasive particles in the polishing composition. Specifically, the surfactant can be used in an amount of 0.5 to 2 parts by weight, for example, 0.6 to 1.5 parts by weight based on 100 parts by weight of the abrasive particles in the polishing composition.

[0073] The accelerator, stabilizer, and surfactant are mixed in a solvent to provide the polishing composition.

[0074] The solvent is ultrapure water, but is not limited to the above example, and any solvent that can be used as a solvent for a polishing composition can be used without any restrictions.

[0075] When contained in the polishing composition within the above range, the stabilizer stabilizes the accelerator, thereby increasing the polishing rate by the accelerator in the polishing composition and improving long-term storage stability.

[0076] In addition, the stabilizer and surfactant can prevent the occurrence of defects during the polishing process using the polishing composition.

[0077] If the surfactant is contained in an amount less than the range, the occurrence of surface defects on the semiconductor substrate during the polishing process increases, whereas if the surfactant is contained in an amount exceeding the range, a large amount of bubbles is generated during the preparation of the polishing composition.

[0078] The composition for semiconductor processing may have a solid content of about 5% by weight to about 20% by weight. If the solid content is too low, the polishing rate for the amorphous carbon film may not be sufficiently ensured, and if the solid content is too high, defects may occur due to aggregation of the abrasive particles. That is, if the composition for semiconductor processing contains each of the above-mentioned components and the solvent and satisfies the above range of solid content, it may be advantageous to inject the composition for semiconductor processing at a uniform flow rate when applied to a polishing process, and it may be advantageous to ensure uniform dispersion and storage stability during distribution and storage of the composition for semiconductor processing.

[0079] The method for producing a polishing composition for semiconductor processing of the present invention includes the steps of preparing a polishing solution by mixing a stabilizer and an accelerator in a solvent, mixing a pH adjuster into the polishing solution to adjust the pH of the polishing solution, and mixing a surfactant and abrasive particles into the polishing solution whose pH has been adjusted, and the value according to the following formula 1 is 0.5 to 2:

[0080] [Formula 1] JPEG0007653511000005.jpg1639, where When an amorphous carbon layer (ACL) having a thickness of 2,000 Å was polished for 60 seconds at 2 psi, a carrier speed of 87 rpm, a platen speed of 93 rpm, and an inflow rate of the polishing composition of 200 ml / min, The Ra is a measured polishing rate; The above S is the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles.

[0081] In the step of preparing the polishing solution, a stabilizer may be mixed with a solvent to prepare a first polishing solution for stabilizing the accelerator, and then an accelerator may be mixed therewith to prepare a polishing solution.

[0082] If the accelerator is prepared by mixing a stabilizer, a pH adjuster, a surfactant, and abrasive particles with ultrapure water as a solvent, the accelerator is not stabilized, and when prepared into a polishing composition, it is difficult to store the accelerator for a long time, and the accelerator does not have the effect of increasing the polishing rate of the amorphous carbon film.

[0083] To prevent this problem, a stabilizer is mixed into a solvent to prepare a first polishing solution, and then an accelerator is dissolved in the first polishing solution to prepare a polishing solution. A pH adjuster is then mixed into the polishing solution to adjust the pH of the polishing solution, and a surfactant and abrasive particles are mixed into the pH-adjusted polishing solution to prepare a polishing composition. The polishing composition for semiconductor processing prepared by the above preparation method has excellent polishing rate for amorphous carbon films due to the accelerator, and is stable and can be stored for a long time.

[0084] A method for manufacturing a semiconductor device according to another embodiment of the present invention includes the steps of: 1) providing a polishing pad including a polishing layer; 2) supplying a polishing composition for semiconductor processing to the polishing pad; and 3) polishing an object to be polished while rotating the polishing pad so that the surface to be polished of the object to be polished contacts the polishing surface of the polishing layer. The polishing composition includes abrasive particles and a surfactant, and has a value of 0.5 to 2 according to the following formula 1:

[0085] [Formula 1] JPEG0007653511000006.jpg1639, where When an amorphous carbon layer (ACL) having a thickness of 2,000 Å was polished for 60 seconds at 2 psi, a carrier speed of 87 rpm, a platen speed of 93 rpm, and an inflow rate of the polishing composition of 200 ml / min, The Ra is a measured polishing rate; The above S is the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles.

[0086] 1 is a schematic diagram of a semiconductor device manufacturing process according to an embodiment. Referring to FIG 1, a polishing pad 110 according to the embodiment is mounted on a platen 120, and then a semiconductor substrate 130 to be polished is placed on the polishing pad 110. For polishing, a polishing slurry 150 is sprayed onto the polishing pad 110 through a nozzle 140.

[0087] The flow rate of the polishing slurry 150 supplied through the nozzle 140 is about 10 cm 3 / min ~ approx. 1,000cm 3 / min. can be selected according to the purpose. For example, about 50 cm 3 / min ~ approx. 500cm 3 / min, but is not limited to this.

[0088] The surface to be polished of the semiconductor substrate 130 directly contacts the polishing surface of the polishing pad 110 .

[0089] Thereafter, the semiconductor substrate 130 and the polishing pad 110 rotate relative to each other to polish the surface of the semiconductor substrate 130. At this time, the rotating direction of the semiconductor substrate 130 and the rotating direction of the polishing pad 110 may be the same or opposite to each other. The rotating speeds of the semiconductor substrate 130 and the polishing pad 110 may be selected according to the purpose within a range of about 10 rpm to about 500 rpm, respectively, and may be, for example, about 30 rpm to about 200 rpm, but are not limited thereto.

[0090] As an example of the polishing process of the substrate, the material polished onto the substrate is an organic film, and the polishing process can be applied to a carbon-based organic film.

[0091] Specifically, the carbon-based organic film can be exemplified by a C-SOH (spin on hardmask) film, an amorphous carbon film, or an NCP film, and is preferably an amorphous carbon film that has excellent selective polishing effect and can exhibit a high polishing rate.

[0092] A specific description of the polishing composition for semiconductor processing overlaps with the description given above, so that description will be omitted.

[0093] In one embodiment, the method for manufacturing a semiconductor device may further include a step of processing the polishing surface of the polishing pad 110 via a conditioner 170 simultaneously with polishing the semiconductor substrate 130 in order to maintain the polishing surface of the polishing pad 110 in a state suitable for polishing.

[0094] Production of semiconductor polishing composition Example 1

[0095] Alanine as a stabilizer was mixed with ultrapure water to prepare a first polishing solution, and cerium ammonium nitrate as an accelerator was mixed with the first polishing solution to prepare a polishing solution.

[0096] The polishing solution was mixed with nitric acid to adjust the pH to 2.1, and the surfactant, Chemours, was added. tm The polishing composition was prepared by mixing FS-30 from Abrasives Inc. and colloidal silica having a diameter of 75 nm.

[0097] Example 2 A polishing composition was prepared in the same manner as in Example 1, except that the surfactant was contained in an amount of 2 parts by weight per 100 parts by weight of colloidal silica.

[0098] Example 3 A polishing composition was prepared in the same manner as in Example 1, except that histidine was used instead of the alanine.

[0099] Example 4 A polishing composition was prepared in the same manner as in Example 1, except that proline was used instead of alanine.

[0100] Example 5 A polishing composition was prepared in the same manner as in Example 1, except that arginine was used instead of the alanine.

[0101] Comparative Example 1 Ultrapure water was used as Comparative Example 1.

[0102] Comparative Example 2 A polishing composition was prepared similarly to Example 1, except that no additional surfactant was added.

[0103] Comparative Example 3 A polishing composition was prepared in the same manner as in Example 1, except that a pyridine salt of a cationic surfactant was used as the surfactant.

[0104] Comparative Example 4 A polishing composition was prepared in the same manner as in Example 1, except that Tween 20, a nonionic surfactant, was used as the surfactant.

[0105] Specific contents for Examples 1 to 5 and Comparative Examples 1 to 4 are as shown in Table 1 below.

[0106] JPEG0007653511000007.jpg213161

[0107] Experimental Example 1 Surface tension measurement Ultrapure water was used as a control, and the bubble life time was measured for Comparative Example 1, Example 1, and Example 2 to evaluate the surface tension.

[0108] The measuring device used was a SITA Bubble Pressure Tensionmeter. After adjusting the volume of the sample to 100 ml, the lifetime of bubbles on the liquid surface due to surface tension was measured. The results are shown in Figure 2.

[0109] It can be seen that for the control group, ultrapure water, no change occurs at a specific surface tension value as the bubble lifetime increases.

[0110] In Comparative Example 1, Example 1, and Example 2, it can be seen that the surface tension decreases with an increase in bubble lifetime due to the components of the polishing composition compared to the control group, but it can be seen that the surface tension decreases as the content of the surfactant increases compared to Comparative Example 1. Specifically, the decrease in surface tension can prevent re-adsorption of carbon residues onto the substrate surface, which means that the occurrence of defects on the semiconductor substrate during the polishing process can be reduced.

[0111] In contrast, in the cases of Comparative Examples 2 to 4, polishing compositions were prepared using different types of surfactants, but aggregation occurred in the polishing compositions, making it impossible to proceed with further evaluation experiments.

[0112] Experimental Example 2 Polishing rate and occurrence of surface defects on semiconductor substrates In order to confirm the polishing rate when the polishing composition of the present invention is applied to a polishing process and whether or not surface defects occur on a semiconductor substrate, the polishing process was carried out, and the polishing rate was measured and whether or not surface defects occurred was confirmed.

[0113] The polishing process conditions were as follows: a 2,000 Å thick amorphous carbon layer (ACL) was pressurized at 2 psi for 60 seconds, the carrier speed was 87 rpm, the platen speed was 93 rpm, and the inflow rate of the polishing composition was 200 ml / min.

[0114] The polishing rate of the amorphous carbon film under the above polishing conditions was measured, and the occurrence of defects was confirmed using KLA Tencor AIT-XP+.

[0115] The value of Equation 1 calculated from the measured removal rate, the weight parts of the abrasive particles and the surfactant is as follows:

[0116] [Formula 1] JPEG0007653511000008.jpg1639, where Ra is the polishing rate measurement, S is the part by weight of surfactant per 100 parts by weight of abrasive particles.

[0117] JPEG0007653511000009.jpg77164

[0118] From the results of the above experiments, it can be seen that the polishing rate for the amorphous carbon film varies depending on the accelerator, and all of Examples 1 to 5 and Comparative Example 2, which all contain accelerators, show a polishing rate for the amorphous carbon film of more than 200 Å / min. However, it can be seen that when no surfactant is included, the amount of carbon residue increases, and therefore the total number of defects also increases.

[0119] As a result, it was confirmed that Examples 1 to 5, which satisfy the values ​​of the formula 1, are excellent in the polishing rate for the amorphous carbon film and are excellent in the effect of preventing the occurrence of defects after the polishing process.

[0120] Although the preferred embodiments of the present invention 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 concept of the present invention defined in the following claims also fall within the scope of the present invention. [Explanation of symbols]

[0121] 110: Polishing pad 120: Fixed plate 130: Semiconductor substrate 140: Nozzle 150: Abrasive slurry 160: Polishing head 170: Conditioner [Industrial Applicability]

[0122] The present invention relates to a polishing composition for semiconductor processing, a method for producing the polishing composition, and a method for producing a semiconductor element using the polishing composition.

Claims

1. comprising an abrasive particle, an accelerator and a surfactant, The accelerator comprises a cerium salt; The value according to the following formula 1 is 0.5 to 2. Polishing composition for semiconductor processing: [Formula 1] Where: When an amorphous carbon layer (ACL) having a thickness of 2,000 Å was polished under conditions of a pressure of 2 psi for 60 seconds, a carrier speed of 87 rpm, a platen speed of 93 rpm, and an inflow rate of the polishing composition of 200 ml / min, The Ra is a measured polishing rate, The above S is the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles.

2. The polishing composition contains 0.5 to 5 parts by weight of a surfactant based on 100 parts by weight of abrasive particles. The polishing composition for semiconductor processing according to claim 1 .

3. The surfactant includes a nonionic fluorine-based polymer compound. The polishing composition for semiconductor processing according to claim 1 .

4. The abrasive particles are selected from the group consisting of metal oxides, organic particles, organic-inorganic composite particles, and mixtures thereof; The polishing composition for semiconductor processing according to claim 1 .

5. The polishing composition comprises a stabilizer and a pH adjuster. The polishing composition for semiconductor processing according to claim 1 .

6. The stabilizer is an amino acid. The polishing composition for semiconductor processing according to claim 5 .

7. mixing a stabilizer and an accelerator in a solvent to produce a polishing solution; adjusting the pH of the polishing solution by mixing a pH adjuster into the polishing solution; mixing a surfactant and abrasive particles into the pH adjusted polishing solution; The accelerator comprises a cerium salt; The value according to the following formula 1 is 0.5 to 2. Method for producing polishing composition for semiconductor process: [Formula 1] Where: When an amorphous carbon layer (ACL) having a thickness of 2,000 Å was polished under conditions of a pressure of 2 psi for 60 seconds, a carrier speed of 87 rpm, a platen speed of 93 rpm, and an inflow rate of the polishing composition of 200 ml / min, The Ra is a measured polishing rate, The above S is the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles.

8. The step of preparing the polishing solution includes: A first polishing solution is prepared by mixing a stabilizer into a solvent, and an accelerator is mixed into the first polishing solution. The method for producing the polishing composition for semiconductor processing according to claim 7 .

9. 1) providing a polishing pad comprising a polishing layer; 2) supplying a polishing composition for semiconductor processing to the polishing pad; 3) polishing the object to be polished while rotating the object to be polished so that the surface to be polished contacts the polishing surface of the polishing layer, The polishing composition comprises abrasive particles, an accelerator, and a surfactant; The accelerator comprises a cerium salt; The value according to the following formula 1 is 0.5 to 2. Manufacturing method of semiconductor device: [Formula 1] Where: When an amorphous carbon layer (ACL) having a thickness of 2,000 Å was polished under conditions of a pressure of 2 psi for 60 seconds, a carrier speed of 87 rpm, a platen speed of 93 rpm, and an inflow rate of the polishing composition of 200 ml / min, The Ra is a measured polishing rate, The above S is the part by weight of the surfactant relative to 100 parts by weight of the abrasive particles.

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