Polishing composition for semiconductor process, method for preparing polishing composition, and method for manufacturing semiconductor device using polishing composition

Abstract

The present invention relates to a polishing composition for semiconductor processes, a method for preparing the polishing composition, and a method for manufacturing a semiconductor device using the polishing composition, and more particularly, to a polishing composition capable of being applied to a polishing process of an amorphous carbon layer (ACL), exhibiting a high polishing rate, preventing carbon residues from being re-adsorbed on a semiconductor substrate during the polishing process, thereby preventing defects from occurring, and further having excellent storage stability. In addition, the present invention can provide a method for manufacturing a semiconductor device using the polishing composition for semiconductor processes.

Description

Technical Field

[0001] This invention relates to polishing compositions for semiconductor processes, methods for preparing polishing compositions, and methods for manufacturing semiconductor devices. Background Technology

[0002] As semiconductor devices become smaller and denser, more sophisticated patterning techniques are being used, leading to more complex surface structures and increased step differences between interlayer films. In the semiconductor device manufacturing process, chemical mechanical polishing (CMP) is used as a planarization technique to remove step differences in specific films formed on a substrate.

[0003] In the CMP process, a slurry is applied to a polishing pad while the substrate is pressurized and rotated to polish its surface. The object to be planarized varies depending on the process step, and the properties of the slurry used also differ accordingly.

[0004] Specifically, CMP technology is not only used for planarization of dielectrics such as silicon oxide (SiO2) and silicon nitride (SiN), but it is also essential for planarization of metal wiring such as tungsten (W) and copper (Cu).

[0005] With the increasing integration of semiconductor devices, there is a need to form more intricate patterns and multi-layered circuit structures.

[0006] Therefore, films made of various materials with different etch selectivity are needed. Among these films made of various materials, carbon-based organic films have good etch selectivity characteristics compared to other silicon-containing films and can be used as mask films or sacrificial films.

[0007] In semiconductor manufacturing processes, organic films need to be removed using chemical mechanical polishing (CMP). However, a polishing composition has not yet been developed that can effectively polish organic films used in semiconductor manufacturing processes by applying CMP.

[0008] Therefore, there is a need to develop polishing compositions for semiconductor processes that can solve the above problems. Summary of the Invention

[0009] The problem the invention aims to solve

[0010] The purpose of this invention is to provide a polishing composition for semiconductor processes, a method for preparing the polishing composition, and a method for manufacturing semiconductor devices using the polishing composition.

[0011] Another object of the present invention is to provide a polishing composition for semiconductor processes, wherein the polishing composition can be applied to the polishing process of amorphous carbon layer (ACL) and exhibits a high polishing rate, and can prevent carbon residue in the polishing process from adsorbing onto the semiconductor substrate, thereby preventing defects from occurring.

[0012] Another object of the present invention is to provide a method for preparing a polishing composition for semiconductor processes, wherein the polishing composition is stabilized by an accelerator in the polishing composition, thereby maintaining polishing performance at high temperatures and having high storage stability.

[0013] Another object of the present invention is to provide a method for manufacturing a semiconductor device using a polishing composition suitable for semiconductor processes.

[0014] means for solving problems

[0015] To achieve the above objectives, a polishing composition for semiconductor processes according to an embodiment of the present invention may include polishing particles, an accelerator, and a stabilizer.

[0016] A method for preparing a polishing composition for semiconductor processes according to another embodiment of the present invention may include the following steps: step a), adding a stabilizer and an accelerator to a solvent and mixing them to prepare a polishing solution; step b), adding a pH adjuster to the polishing solution to adjust the pH value of the polishing solution to 2 to 5; and step c), mixing a surfactant and polishing particles in the polishing solution with a pH value of 2 to 5.

[0017] A method for manufacturing a semiconductor device according to another embodiment of the present invention may include the following steps: step 1), providing a polishing pad including a polishing layer; step 2), providing a polishing composition for semiconductor processing to the polishing pad; step 3), rotating the object to be polished relative to the polishing surface of the polishing layer in such a way that the polished surface of the object is in contact with the polishing surface of the polishing layer, thereby polishing the object. Furthermore, the polished surface is an amorphous carbon film, and the polishing composition may contain polishing particles, an accelerator, and a stabilizer.

[0018] Invention Effects

[0019] The polishing composition according to the present invention can be applied to the polishing process of amorphous carbon layer (ACL) and exhibits a high polishing rate; it can prevent carbon residue from adsorbing onto the semiconductor substrate during the polishing process, thereby preventing defects; and it has excellent polishing performance retention at high temperatures and excellent storage stability.

[0020] In addition, a method for manufacturing a semiconductor device using the polishing composition for semiconductor processing can be provided. Attached Figure Description

[0021] Figure 1 This is a schematic process diagram of a semiconductor device manufacturing process according to an embodiment of the present invention.

[0022] Explanation of reference numerals in the attached figures

[0023] 110: Polishing pad

[0024] 120: Tablet

[0025] 130: Semiconductor substrate

[0026] 140: Nozzle

[0027] 150: Polishing slurry

[0028] 160: Polishing head

[0029] 170: Dresser Detailed Implementation

[0030] This invention relates to a polishing composition for semiconductor processes, the polishing composition comprising polishing particles, an accelerator, and a stabilizer. Specific Implementation

[0032] The embodiments of the present invention are described in detail below to enable those skilled in the art to implement the invention. However, the present invention can be implemented in various different forms and is not limited to the embodiments described herein.

[0033] In this specification, unless otherwise stated, "includes" another component means that it may also include other components, rather than excluding other components.

[0034] In this specification, when a structure is referred to as being "connected" to another constituent element, this includes not only the case of "direct connection" but also the case of "connection with other constituent elements in between".

[0035] In this specification, "B is located on A" means that B is located on A in direct contact with A or in the presence of other layers in between. It should not be interpreted as only meaning that B is located on the surface of A in contact with A.

[0036] In this specification, the term "mixture of them" included in the Markush type description refers to a mixture or combination of one or more of the constituent elements selected from the group consisting of the multiple constituent elements of the Markush type description, thereby indicating that it includes one or more of the constituent elements selected from the group consisting of the multiple constituent elements mentioned above.

[0037] In this specification, the reference to "A and / or B" means "A, B, or A and B".

[0038] In this specification, unless otherwise stated, terms such as “first,” “second,” or “A,” “B,” etc., are used to distinguish the same terms from each other.

[0039] In this specification, unless otherwise stated, the use of the singular can be interpreted to include the meaning of either the singular or the plural as may be understood from the context.

[0040] The present invention will now be described in more detail.

[0041] As semiconductor devices become smaller and denser, their surface structures become more complex. This increased complexity means that the linewidth of the semiconductor becomes narrower, and the aspect ratio (the ratio of the horizontal to the vertical dimension) gradually increases. To accommodate the ever-increasing aspect ratio, the photoresist also becomes thinner.

[0042] However, the thinned and elongated photoresist cannot withstand the etching process and will tilt. To prevent this phenomenon, a hard mask process was introduced.

[0043] Amorphous carbon and SiON were used as the hard mask materials.

[0044] Although the amorphous carbon exhibits excellent etch resistance when used as a hard mask, when applied to a chemical mechanical polishing process using conventional polishing compositions, the polishing rate is low and carbon residue is generated. This carbon residue adsorbs onto the thin film surface, leading to defects in the semiconductor substrate.

[0045] Therefore, the polishing composition for semiconductor processes of the present invention not only exhibits a high polishing rate for amorphous carbon films, but also prevents the reabsorption of carbon residues and prevents defects in the semiconductor substrate.

[0046] Specifically, the polishing composition provided for the polishing process of amorphous carbon layer (ACL) may contain polishing particles, an accelerator, and a stabilizer.

[0047] The weight ratio of the accelerator to the stabilizer can be from 0.5:1 to 3:1.

[0048] As mentioned above, conventional polishing compositions used in amorphous carbon film polishing processes have low polishing rates, thus resulting in reduced efficiency of the polishing process.

[0049] To improve the above problems, the polishing rate of amorphous carbon films has been increased by including accelerators in conventional polishing compositions. However, due to the inclusion of accelerators, not only does the number of defects such as carbon residue adsorption on the semiconductor substrate increase, but contamination of the polishing pad also occurs, regardless of the polishing rate of the amorphous carbon film polishing process.

[0050] Furthermore, when the polishing process is carried out at temperatures above 60°C, a decrease in polishing rate occurs. This decrease also occurs when the polishing rate is applied to the polishing process after long-term storage, indicating a decrease in the stability of the polishing composition.

[0051] Therefore, the present invention can provide a polishing composition that can improve the polishing rate of amorphous carbon films, prevent contamination of polishing pads, prevent the reduction of polishing performance at high temperatures, and has excellent long-term storage stability.

[0052] Specifically, the polishing composition of the present invention comprises polishing particles, an accelerator, and a stabilizer. Because it contains an accelerator and a stabilizer, it is possible to increase the polishing rate of the accelerator-based amorphous carbon film and improve the stability of the stabilizer-based polishing composition.

[0053] Specifically, the weight ratio of the accelerator to the stabilizer can be 0.5:1 to 3:1, 0.5:1 to 2:1, or 0.55:1 to 1.9:1. When used in combination within the above ranges, not only is the polishing rate of amorphous carbon films high, but it also prevents carbon residues from adsorbing onto the semiconductor substrate during the polishing process. Furthermore, it prevents the problem of reduced polishing rate even in polishing processes performed at temperatures above 60°C, and it also prevents the polishing rate from decreasing even during long-term storage.

[0054] The accelerator can be selected from the group consisting of anionic small molecules, anionic polymers, hydroxy acids, amino acids, and cerium salts. Specifically, the cerium salt can be a trivalent or tetravalent cerium salt. More specifically, the tetravalent cerium salt can be selected from the group consisting of cerium(IV) sulfate (Ce(SO4)2), cerium ammonium sulfate dihydrate, and cerium ammonium nitrate, but is not limited to the examples described.

[0055] The accelerator is incorporated into the polishing composition, facilitating the removal of the surface layer of the amorphous carbon film by oxidizing the surface layer into oxides or ions. Furthermore, it offers the advantage of easily removing organic film residues present in the polishing stop film layer, resulting in more uniform polishing.

[0056] The cerium ammonium nitrate can exist in the slurry composition in the form of an ionic compound or a chelate, and when used in the form of said compound, it can provide a high polishing speed for amorphous carbon films.

[0057] The stabilizer is used to improve the stability of the polishing composition and prevent defects from occurring in the polishing process. The stabilizer is an amino acid, and more specifically, the amino acid can 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, preferably alanine, but not limited to the examples described. Any amino acid that can improve the stability of the polishing composition by being mixed with an accelerator and can inhibit the occurrence of defects in the polishing process can be used without restriction.

[0058] More specifically, for the polishing composition used in the semiconductor process, the polishing performance degradation rate (PPR), expressed by Formula 1 below, can be from 0% to 60%.

[0059] [Formula 1]

[0060]

[0061] Specifically, under polishing conditions of 2 psi, carrier speed of 87 rpm, platen speed of 93 rpm, and inflow rate of polishing composition of 200 ml / min, a thickness of 2000 angstroms was tested. An amorphous carbon layer (ACL) was polished for 60 seconds. Here, A0 is the polishing rate measured under the polishing conditions using the polishing composition in the polishing process; A1 is the polishing rate measured under the polishing conditions after the polishing composition has been placed at 60°C for 40 hours and cooled to 20°C to 25°C.

[0062] In many cases, after the polishing composition for semiconductor processes is prepared, it needs to be stored for a considerable period of time before being used in the actual polishing process. Therefore, the polishing composition must have excellent storage stability. In other words, the polishing composition is not used immediately after preparation, but may take several days for transfer and storage before actual use in the polishing process. During the long-term storage of the prepared polishing composition, particle agglomeration may occur, or the polishing performance may decrease due to changes in composition. These issues are related to ensuring stability during long-term storage.

[0063] To evaluate the stability, it is necessary to confirm the degree of change in polishing performance after long-term storage.

[0064] To confirm the stability, in the case of the present invention, the polishing composition was placed at a high temperature of 60°C for 40 hours, thereby confirming the degree of decrease in polishing performance.

[0065] The polishing composition is placed at 60°C to evaluate its stability under harsh conditions. Placing it at 60°C for 1 hour is analogous to storing it at room temperature (15°C to 25°C) for approximately 1 day. As mentioned above, placing it at 60°C for 40 hours implies a polishing composition stored for approximately 40 days.

[0066] With regard to the polishing composition of the present invention, even after being placed under harsh conditions of 60°C for 40 hours, the polishing performance degradation rate (PPR) is 0% to 60%, or 0% to 30%, or 0% to 10%, or 0% to 5%. Exhibiting a polishing performance degradation rate within the above range means exhibiting excellent stability based on long-term storage.

[0067] The polishing particles are polishing particles that can be applied to polishing compositions for semiconductor processes, and may be selected from metal oxides, organic particles, organic-inorganic composite particles, and mixtures thereof.

[0068] Specifically, the metal oxide may be selected from colloidal silica, fumed silica, cerium dioxide, alumina, titanium dioxide, zirconium oxide, zeolite, and mixtures thereof, but is not limited to the examples described. Any polishing particles that can be selected by those skilled in the art can be used without restriction.

[0069] The organic particles can be polystyrene, styrene-based copolymers, poly(meth)acrylate, (meth)acrylate-based copolymers, polyvinyl chloride, polyamide, polycarbonate, and polyimide polymers; or the polymers can form particles with a core, shell, or a core / shell structure, and they can be used alone or in combination. The organic particles can be prepared by emulsion polymerization, suspension polymerization, etc.

[0070] Specifically, the polishing particles of the present invention can be selected from the group consisting of colloidal silica, fumed silica, cerium dioxide, and mixtures thereof.

[0071] The diameter (D) of the polishing particles 50 The diameter can be from 10nm to 120nm, preferably, the diameter (D) 50 The diameter can be from 20nm to 100nm, more preferably, the diameter (D) 50 The diameter can be from 20 nm to 80 nm. When the diameter of the metal oxide particles is greater than 120 nm, the possibility of defects such as scratches on the substrate to be polished increases, and when the diameter is less than 20 nm, the dispersion of the particles may become worse.

[0072] The polishing composition may additionally contain surfactants and pH adjusters.

[0073] When an accelerator is included in the polishing composition to increase the polishing rate of the amorphous carbon film, the polishing rate is increased, but the following problems arise: carbon residue generated during the polishing process adsorbs onto the semiconductor substrate and polishing pad contamination occurs.

[0074] To address the aforementioned issues, a surfactant is incorporated into the polishing composition to reduce its surface tension. This reduction in surface tension prevents carbon residues from re-adsorbing onto the substrate surface and also prevents contamination of the polishing pad.

[0075] Specifically, the surfactant may include a nonionic fluorinated polymer. The surfactant, including the fluorinated polymer, can prevent carbon residues from re-adsorbing onto the surface of the semiconductor substrate when used in the polishing process of amorphous carbon films.

[0076] Furthermore, because the surfactant contains fluorine, it can inhibit the growth of microorganisms such as bacteria and mold. When the polishing composition is stored for a long time, bacteria and mold may grow, and the polishing composition with such bacteria and mold cannot be used in the polishing process and must be discarded.

[0077] In the polishing composition of the present invention, the surfactant includes a nonionic fluorinated polymer compound, which prevents the growth of bacteria and mold when the polishing composition is stored for a long time, thereby improving long-term storage stability.

[0078] The surfactant of this invention can be specifically selected from Chemours. tm The group consisting of FS-30, FS-31, FS-34, ET-3015, ET-3150, ET-3050 and mixtures thereof from the company, but is not particularly limited as long as it is a substance that can prevent carbon residues from being re-adsorbed onto the surface of the semiconductor substrate.

[0079] The surfactant described in this invention is a nonionic surfactant, which can be used alone, including nonionic fluorinated polymers, or in combination with other nonionic surfactants.

[0080] The nonionic surfactant can be selected from the group consisting of polyethylene glycol, polypropylene glycol, polyethylene-propylene copolymer, polyalkyl oxide, polyethylene oxide (PEO), polyethylene oxide, and polypropylene oxide. The fluorosurfactant can be selected from the group consisting of sodium sulfonate fluorosurfactant, phosphate ester fluorosurfactant, amine oxide fluorosurfactant, betaine fluorosurfactant, ammonium carboxylate fluorosurfactant, stearate ester fluorosurfactant, quaternary ammonium fluorosurfactant, and ethylene oxide / propylene oxide fluorosurfactant. The group consists of fluorosurfactant and polyoxyethylene fluorosurfactant.

[0081] The pH adjuster may be selected from at least one of the following groups: 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, citric acid, acetic acid, propionic acid, fumaric acid, oleic acid, salicylic acid, pimelic acid, benzoic acid, succinic acid, phthalic acid, butyric acid, glutaric acid, glycolic acid, lactic acid, aspartic acid, tartaric acid, and potassium hydroxide.

[0082] The pH adjuster can adjust the pH value of the polishing composition for semiconductor processes to 2 to 5, or preferably 2 to 4. Maintaining an acidic environment within this range allows for the preservation of polishing speed and quality while preventing excessive corrosion of the metal components or polishing equipment.

[0083] The polishing composition for semiconductor processes may comprise 0.1% to 0.5% by weight polishing particles, 1% to 2% by weight accelerator, 1% to 2% by weight stabilizer, 0.001% to 0.01% by weight surfactant, and the remainder being a solvent. When the content of the polishing composition is within the above range, the accelerator becomes stable due to the stabilizer, thereby increasing the accelerator-based polishing rate in the polishing composition, and the stabilizer and surfactant prevent the occurrence of defects in the polishing process.

[0084] The solvent is ultrapure water, but is not limited to the example above; any solvent that can be used as a solvent for the polishing composition can be used without restriction.

[0085] When the content of the surfactant is less than the above-mentioned range, the defects occurring on the surface of the semiconductor substrate increase during the polishing process, and when the content of the surfactant is greater than the above-mentioned range, a large number of bubbles are generated during the preparation of the polishing composition.

[0086] The polishing composition is provided to a polishing process of an amorphous carbon layer (ACL), and the polishing rate of the amorphous carbon layer can be 190 Å / min or higher. As mentioned above, when the polishing rate of the amorphous carbon layer is 190 Å / min or higher, it can be said that the polishing rate of the amorphous carbon layer is excellent.

[0087] Even if the weight ratio of the accelerator and stabilizer contained in the polishing composition is within the range of the present invention, a low polishing rate may occur due to the low content of the accelerator relative to the polishing particles. Therefore, in order for the polishing composition of the present invention to exhibit a high polishing rate for amorphous carbon films, prevent the occurrence of defects in the polishing process, prevent contamination of the polishing pad, and increase the stability of the polishing composition, it is necessary not only to meet the range of the weight ratio of the accelerator and stabilizer, but also to meet the above-mentioned content range for the polishing composition of the present invention.

[0088] The method for preparing the polishing composition according to the present invention may include the following steps: step a), adding and mixing a stabilizer and an accelerator in a solvent to prepare a polishing solution; step b), adding a pH adjuster to the polishing solution to adjust the pH value of the polishing solution to 2 to 5; and step c), mixing a surfactant and polishing particles in the polishing solution with a pH value of 2 to 5.

[0089] In step a), in order to stabilize the accelerator, the stabilizer can be mixed in the solvent to prepare the first solvent, and then the accelerator can be mixed in to prepare the polishing solution.

[0090] Regarding the accelerator, when it is prepared by mixing ultrapure water as a solvent with other stabilizers, pH adjusters, surfactants and polishing particles, the accelerator is unstable in the polishing composition, making it difficult to store for a long time when preparing the polishing composition, or it may not show the effect of increasing the polishing rate based on the accelerator in the polishing composition.

[0091] To prevent this problem, after mixing a stabilizer in a solvent to prepare a first solution, an accelerator is dissolved in the first solution to prepare a polishing solution, and then a polishing composition is prepared through subsequent steps.

[0092] A method for manufacturing a semiconductor device according to another embodiment of the present invention may include the following steps: step 1), providing a polishing pad including a polishing layer; step 2), providing a polishing composition for semiconductor processing to the polishing pad; step 3), rotating the object to be polished relative to the polishing surface of the polishing layer in such a way that the polished surface of the object is in contact with the polishing surface of the polishing layer, thereby polishing the object. Furthermore, the polished surface is an amorphous carbon film, and the polishing composition may contain polishing particles, an accelerator, and a stabilizer, and the weight ratio of the accelerator to the stabilizer may be from 0.5:1 to 2:1.

[0093] Figure 1 This is a schematic process diagram illustrating a semiconductor device manufacturing process according to an embodiment of the present invention. (Refer to...) Figure 1 After mounting a polishing pad 110 according to one embodiment on a flat plate 120, a semiconductor substrate 130, which is to be polished, is arranged on the polishing pad 110. For polishing, polishing slurry 150 is sprayed onto the polishing pad 110 through a nozzle 140.

[0094] The flow rate of the polishing slurry 150 supplied through the nozzle 140 can be approximately 10 cm. 3 / min to approximately 1000cm 3 The range of / min should be selected based on the purpose; for example, it could be approximately 50cm. 3 / min to approximately 500cm 3 / min, but not limited to this.

[0095] The polished surface of the semiconductor substrate 130 is in direct contact with the polished surface of the polishing pad 110.

[0096] Subsequently, the semiconductor substrate 130 and the polishing pad 110 rotate relative to each other, thereby enabling the surface of the semiconductor substrate 130 to be polished. At this time, the rotation direction of the semiconductor substrate 130 and the rotation direction of the polishing pad 110 can be the same or opposite. The rotation speed of the semiconductor substrate 130 and the polishing pad 110 can be selected from approximately 10 rpm to approximately 500 rpm depending on the purpose, for example, from approximately 30 rpm to approximately 200 rpm, but is not limited thereto.

[0097] As an example of the polishing process for the substrate, the organic film of the substrate is polished, which can be applied to the polishing process of carbon-based organic films.

[0098] Specifically, examples of carbon-based organic films include C-SOH (spin-on hard mask) films, amorphous carbon films, or NCP films, with amorphous carbon films being preferred as they exhibit excellent selective polishing effects and can demonstrate high polishing rates.

[0099] The specific description of the polishing composition for semiconductor processes is repeated above, so it is omitted here.

[0100] In one embodiment, in order to keep the polishing surface of the polishing pad 110 in a state suitable for polishing, the method for fabricating the semiconductor device may further include the following steps: that is, while polishing the semiconductor substrate 130, the polishing surface of the polishing pad 110 is processed by a dressing device 170.

[0101] Preparation of compositions for semiconductor polishing

[0102] Example 1

[0103] A polishing solution was prepared by mixing alanine as a stabilizer in ultrapure water to form a mixed solution, followed by mixing cerium ammonium nitrate.

[0104] Nitric acid was mixed into the polishing solution to adjust the pH to 2.1, and then Chemours was added. tm A polishing composition was prepared by using the surfactant FS-30 from the company and colloidal silica with a diameter of 75 nm.

[0105] The weights of the accelerators and stabilizers in the embodiments and comparative examples are shown in Table 1 below.

[0106] [Table 1]

[0107]

[0108]

[0109] (Unit: weight %; the remainder is ultrapure water)

[0110] Experimental Example

[0111] Polishing rate and whether defects occur on the surface of the semiconductor substrate.

[0112] To determine the polishing rate when the polishing composition of the present invention is applied to a polishing process and whether surface defects occur on the semiconductor substrate, a polishing process was performed to measure the polishing rate and to confirm whether defects occurred on the surface.

[0113] The specific polishing process conditions are as follows: an amorphous carbon film (ACL) with a thickness of 2000 angstroms is polished for 60 seconds under the polishing conditions of 2 psi, carrier speed of 87 rpm, platform speed of 93 rpm, and inflow rate of polishing composition of 200 ml / min.

[0114] The polishing rate A0 of the amorphous carbon film under the polishing conditions was measured, and the presence of defects was confirmed using KLA Tencor AIT-XP+.

[0115] In addition, the polishing compositions of the embodiments and comparative examples were placed in an oven heated to 60°C and kept there for 40 hours, then cooled to 20°C to 25°C, and then polished under the same conditions as above, thereby determining the polishing rate A1 of the amorphous carbon film.

[0116] The polishing performance degradation rate (PPR), expressed by Equation 1 below, was calculated using the measured polishing rate:

[0117] [Formula 1]

[0118]

[0119] A 2000 angstrom-thickness amorphous carbon layer (ACL) was polished for 60 seconds under the following polishing conditions: 2 psi, carrier speed 87 rpm, platform speed 93 rpm, and inflow rate of the polishing composition 200 ml / min. A0 is the polishing rate measured under these conditions when the polishing composition was used in the polishing process; A1 is the polishing rate measured under the same conditions after the polishing composition was placed at 60°C for 40 hours and cooled to 20°C-25°C.

[0120] [Table 2]

[0121] A0 (angstroms / minute) A1 (angstroms per minute) PPR (%) Defects (number) Example 1 203 199 2 11089 Example 2 266 261 2 12274 Example 3 194 194 0 15122 Example 4 258 258 0 8056 Example 5 124 25 80 40630 Comparative Example 1 172 41 76 15137 Comparative Example 2 182 182 0 35614 Comparative Example 3 172 55 68 16620

[0122] Table 2 above confirms the polishing rate, polishing performance degradation rate (PRR), and defect occurrence for Examples 1 to 5 and Comparative Examples 1 to 3. The polishing rates of the polishing compositions in Examples 1 to 4 ranged from 194 Å / min to 266 Å / min, meaning that the polishing rates for amorphous carbon films were all above 190 Å / min, confirming excellent polishing rates for amorphous carbon films. Furthermore, even when the polishing process was performed after heating and cooling at a high temperature of 60°C, the polishing rates were still confirmed to be above 190 Å / min, meaning that the polishing performance did not decrease or the decrease was very small, thus confirming the excellent stability of the polishing compositions.

[0123] However, in Example 5, although the accelerator and stabilizer are included within the weight ratio range of the present invention, the content range of the accelerator and stabilizer in the polishing composition is not within the range of the present invention. Therefore, the polishing rate is low, and a large reduction rate is also shown in the polishing rate measured after heating at high temperature, thus confirming poor stability.

[0124] In Comparative Example 1, the polishing rate before heating was 172 Å / min, and the polishing rate after heating was 41 Å / min, thus confirming a value of 76% according to Equation 1. In Comparative Example 2, the polishing rate before heating was 182 Å / min, and the polishing rate after heating was also 182 Å / min, i.e., no change. However, for amorphous carbon films, the polishing rate was below 190 Å / min, and 35,614 defects were confirmed. In Comparative Example 3, the polishing rate before heating was 172 Å / min, and the polishing rate after heating was 55 Å / min, with a value of 68% according to Equation 1, thus confirming a very large reduction in polishing rate. In the cases of the comparative examples, where there was a large difference in polishing rate before and after heating, or where there was no difference in polishing rate, defects became a problem.

[0125] The preferred embodiments of the present invention have been described in detail above, but the scope of the present invention is not limited thereto. Various modifications and improvements made by those skilled in the art using the basic concepts of the present invention as defined in the claims are all within the scope of the present invention.

[0126] Industrial applicability

[0127] This invention relates to polishing compositions for semiconductor processes, methods for preparing polishing compositions, and methods for manufacturing semiconductor devices using polishing compositions.

Claims

1. A polishing composition for semiconductor processing, wherein, Include: Polishing particles; Accelerator; stabilizers; and Surfactants, The weight ratio of the accelerator to the stabilizer is 0.5:1 to 3:

1. The stabilizer content is 1% to 2% by weight. The surfactant includes fluorinated polymers. The rate of decrease in polishing performance, as expressed by Equation 1 below, ranges from 0% to 60%: [Formula 1] In Equation 1, A polishing process was performed on an amorphous carbon film with a thickness of 2000 Å for 60 seconds under polishing conditions of 2 psi, carrier speed of 87 rpm, platen speed of 93 rpm, and inflow rate of polishing composition of 200 ml / min; A0 is the polishing rate measured under the polishing conditions by using the polishing composition in the polishing process; A1 is the polishing rate measured under the polishing conditions by placing the polishing composition at 60°C for 40 hours and then cooling it to 20°C to 25°C.

2. The polishing composition for semiconductor processing according to claim 1, wherein, The accelerator is selected from the group consisting of anionic small molecules, anionic polymers, hydroxy acids, amino acids and cerium salts.

3. The polishing composition for semiconductor processes according to claim 1, wherein, The stabilizer is an amino acid.

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

5. The polishing composition for semiconductor processing according to claim 1, wherein, The polishing composition contains a pH adjuster.

6. A method for preparing a polishing composition for semiconductor processes, wherein, Includes the following steps: Step a) involves adding and mixing a stabilizer and an accelerator into a solvent to prepare a polishing solution; Step b), add a pH adjuster to the polishing solution to adjust the pH value of the polishing solution to 2 to 5; as well as Step c), in the polishing solution with a pH of 2 to 5, mix the surfactant and polishing particles. The weight ratio of the accelerator to the stabilizer is 0.5:1 to 3:

1. The stabilizer is present in the polishing composition at a content of 1% to 2% by weight. The surfactant includes fluorinated polymers. The rate of decrease in polishing performance, as expressed by Equation 1 below, ranges from 0% to 60%: [Formula 1] In Equation 1, A polishing process was performed on an amorphous carbon film with a thickness of 2000 Å for 60 seconds under polishing conditions of 2 psi, carrier speed of 87 rpm, platen speed of 93 rpm, and inflow rate of polishing composition of 200 ml / min; A0 is the polishing rate measured under the polishing conditions by using the polishing composition in the polishing process; A1 is the polishing rate measured under the polishing conditions by placing the polishing composition at 60°C for 40 hours and then cooling it to 20°C to 25°C.

7. The method for preparing the polishing composition for semiconductor processes according to claim 6, wherein, Step a) is as follows: A stabilizer is mixed in a solvent to prepare a mixed solution, and then an accelerator is mixed in the mixed solution to prepare a polishing solution.

8. A method for manufacturing a semiconductor device, wherein, Includes the following steps: Step 1), provide a polishing pad including a polishing layer; Step 2), providing the polishing pad with a polishing composition for semiconductor processing; as well as Step 3), rotate the object relative to it so that the surface to be polished is in contact with the polishing surface of the polishing layer, thereby polishing the object. The polishing composition comprises polishing particles, an accelerator, a stabilizer, and a surfactant. The weight ratio of the accelerator to the stabilizer is 0.5:1 to 3:

1. The stabilizer content is 1% to 2% by weight. The surfactant includes fluorinated polymers. The rate of decrease in polishing performance, as expressed by Equation 1 below, ranges from 0% to 60%: [Formula 1] In Equation 1, A polishing process was performed on an amorphous carbon film with a thickness of 2000 Å for 60 seconds under polishing conditions of 2 psi, carrier speed of 87 rpm, platen speed of 93 rpm, and inflow rate of polishing composition of 200 ml / min; A0 is the polishing rate measured under the polishing conditions by using the polishing composition in the polishing process; A1 is the polishing rate measured under the polishing conditions by placing the polishing composition at 60°C for 40 hours and then cooling it to 20°C to 25°C.

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