Slurry, polishing method, and component production method

Abstract

Provided is a slurry containing abrasive grains and water, wherein the abrasive grains include cerium oxide particles, and the amount of water adsorbed per unit area of each cerium oxide particle is 0.032 mmol / m2 or more. Additionally provided is a polishing method comprising a step for using the slurry to polish a polishing target member. Further provided is a component production method comprising a step for obtaining a component by using the polishing target member that has been polished by means of the polishing method.

Description

Slurry, polishing method, and method for manufacturing parts

[0001] This disclosure relates to slurry, polishing methods, and methods for manufacturing parts, etc.

[0002] In recent years, the importance of processing technologies for increasing density and miniaturization has been steadily growing in semiconductor device manufacturing processes. One such processing technology, CMP (chemical mechanical polishing), has become an essential technology in semiconductor device manufacturing processes for forming shallow trench isolation (STI), planarizing premetallic insulating materials or interlayer insulating materials, and forming plugs or embedded metal wiring.

[0003] The most commonly used polishing fluids include silica-based polishing fluids containing silica (silicon oxide) particles such as fumed silica and colloidal silica as abrasive grains. Silica-based polishing fluids are characterized by their versatility, and by appropriately selecting the abrasive grain content, pH, additives, etc., they can polish a wide range of materials, including both insulating and conductive materials.

[0004] On the other hand, there is a growing demand for cerium oxide-based polishing solutions containing cerium oxide particles as abrasives. For example, cerium oxide-based polishing solutions can polish insulating materials at high speed even with a lower abrasive content than silica-based polishing solutions (see, for example, Patent Documents 1 and 2 below).

[0005] JP-A-10-106994 JP-A-08-022970

[0006] Incidentally, in recent years, 3D-NAND devices, in which the cell portions of the device are stacked vertically, have been gaining prominence. In this technology, the step height of the insulating material during cell formation is several times higher compared to conventional planar type devices. Consequently, in order to maintain the throughput of device manufacturing, it is necessary to quickly eliminate the aforementioned high step height in the CMP process or other steps, and to improve the polishing speed of the insulating material.

[0007] One aspect of this disclosure aims to provide a slurry capable of achieving a high polishing speed for insulating materials. Another aspect of this disclosure aims to provide a polishing method using such a slurry. Yet another aspect of this disclosure aims to provide a method for manufacturing parts using such a polishing method.

[0008] This disclosure relates, for example, to the following invention: [1] A solution containing abrasive grains and water, wherein the abrasive grains contain cerium oxide particles, and the amount of water adsorbed per unit area of ​​the cerium oxide particles is 0.032 mmol / m². ２ That's all, slari. [2] The water adsorption amount is 0.060 mmol / m ２ The slurry described in [1] is as follows: [3] The BET specific surface area of ​​the cerium oxide particles when water is used as the adsorption medium is 15.0 m². ２ The slurry according to [1] or [2], wherein the amount is 1 / g or more. [4] The BET specific surface area of ​​the cerium oxide particles when nitrogen is used as the adsorption medium is 10.0 to 35.0 m². ２ The slurry according to any one of [1] to [3], wherein the amount is / g. [5] The slurry according to any one of [1] to [4], wherein the BET diameter of the cerium oxide particles is 20.0 to 60.0 nm. [6] The integrated value of the differential pore volume in the range of pore diameter 1.4 to 3.0 nm in the pore distribution curve of the cerium oxide particles is 3.1 × 10 －３ cm ３ [1] to [5] any one of the following: [7] A slurry according to any one of the following: [1] to [6], wherein the volume average particle size of the cerium oxide particles is 150 to 300 nm. [8] A slurry according to any one of the following: [1] to [7], wherein the abrasive content is 0.01 to 10.00 mass%. [9] A slurry according to any one of the following: [1] to [8], wherein the pH is 1.00 to 7.00.

[10] A polishing method comprising the step of polishing a workpiece using a slurry according to any one of the following: [1] to [9].

[11] The polishing method according to

[10] , wherein the workpiece contains silicon dioxide.

[12] A method for manufacturing a part, comprising the step of obtaining a part using the workpiece polished by the polishing method according to

[10] or

[11] .

[0009] According to one aspect of this disclosure, a slurry capable of achieving a high polishing speed for insulating materials can be provided. According to another aspect of this disclosure, a polishing method using such a slurry can be provided. According to yet another aspect of this disclosure, a method for manufacturing parts using such a polishing method can be provided.

[0010] The embodiments of this disclosure will be described in detail below.

[0011] <Definitions> In this specification, numerical ranges indicated using "~" represent a range that includes the numbers listed before and after "~" as the minimum and maximum values, respectively. "A or greater" in a numerical range means A and the range greater than A. "A or less" in a numerical range means A and the range less than A. In numerical ranges described stepwise in this specification, the upper or lower limit of a numerical range in one step can be arbitrarily combined with the upper or lower limit of a numerical range in another step. In numerical ranges described in this specification, the upper or lower limit of that numerical range may be replaced with the values ​​shown in the examples. "A or B" means that either A or B may be included, or both may be included. Unless otherwise specified, the materials exemplified in this specification can be used individually or in combination of two or more. The content of each component in a composition means the total amount of multiple substances present in the composition if there are multiple substances corresponding to each component in the composition, unless otherwise specified. The term "membrane" encompasses not only structures formed across the entire surface when observed in a plan view, but also structures formed only in parts of the surface. The term "process" includes not only independent processes, but also processes that cannot be clearly distinguished from other processes, as long as their intended function is achieved.

[0012] As will be described later, the slurry according to this embodiment contains abrasive grains. Abrasive grains are also called "abrasive particles," but in this specification they are referred to as "abrasive grains." Abrasive grains are generally solid particles, and it is thought that during polishing, the material to be removed is removed by the mechanical action of the abrasive grains and the chemical action of the abrasive grains (mainly the surface of the abrasive grains), but this is not limited to this.

[0013] <Slurry> The slurry according to this embodiment contains abrasive particles and water. The slurry according to this embodiment may be, for example, a polishing slurry and can be used as a polishing liquid (CMP polishing liquid). In this specification, "polishing liquid" is defined as a composition that comes into contact with the surface to be polished during polishing. The term "polishing liquid" itself does not limit the components contained in the polishing liquid in any way.

[0014] In the slurry according to this embodiment, the abrasive particles include cerium oxide particles, and the amount of water adsorbed per unit area of ​​the cerium oxide particles is 0.032 mmol / m². ２ That's all.

[0015] According to the slurry of this embodiment, it is possible to obtain a high polishing speed for insulating materials, for example, a high polishing speed for silicon oxide. According to the slurry of this embodiment, in the evaluation method described in the examples below, a polishing speed of 1650 nm / min or more (preferably 1700 nm / min or more, 1750 nm / min or more, 1800 nm / min or more, etc.) can be obtained for 20 seconds of polishing of insulating material (silicon oxide).

[0016] The factors that enable high polishing speeds for insulating materials are not entirely clear, but they are presumed to be as follows. However, the factors are not limited to those listed below. In other words, the greater the amount of water adsorbed per unit area of ​​cerium oxide particles, the higher the hydrophilicity of the cerium oxide particles. Therefore, the cerium oxide particles diffuse more easily in the slurry, increasing the number of abrasive particles that contribute to polishing. Furthermore, it is presumed that the higher the hydrophilicity of the cerium oxide particles, the greater the interaction with the insulating material, which improves the chemical reactivity of the cerium oxide particles and allows for high polishing speeds of the insulating material.

[0017] According to one embodiment of the slurry according to this embodiment, in the evaluation method described in the later-described examples, a polishing speed of 1500 nm / min or more (preferably 1550 nm / min or more, 1600 nm / min or more, 1650 nm / min or more, 1700 nm / min or more, 1750 nm / min or more, etc.) can be obtained for polishing the insulating material (silicon oxide) for 50 seconds.

[0018] When using a slurry as a cerium oxide-based polishing solution to quickly eliminate high steps in insulating materials (e.g., silicon oxide), a problem arises in that the polishing speed decreases as polishing progresses, resulting in a longer time required to eliminate the steps. Therefore, slurry for eliminating high steps requires both a high initial polishing speed and the ability to maintain that polishing speed. According to one embodiment of the slurry of this embodiment, it is possible to obtain a high polishing speed for insulating materials while suppressing the decrease in polishing speed as polishing progresses. For example, it is possible to obtain a high polishing speed for silicon oxide while suppressing the decrease in polishing speed as polishing progresses. According to one embodiment of the slurry of this embodiment, in the evaluation method described in the examples below, a polishing speed maintenance rate ((polishing speed for 50 seconds of polishing / polishing speed for 20 seconds of polishing) × 100) of, for example, more than 75.0% (preferably 80.0% or more, 85.0% or more, 90.0% or more, 95.0% or more, 99.0% or more, etc.) can be obtained.

[0019] According to this embodiment, it is possible to provide a method for adjusting the polishing speed, which adjusts the polishing speed based on the amount of water adsorbed per unit area of ​​cerium oxide particles, and a method for adjusting the maintenance rate of the polishing speed, which adjusts the maintenance rate of the polishing speed based on the amount of water adsorbed per unit area of ​​cerium oxide particles. According to this embodiment, it is possible to provide a method for selecting abrasive grains, which selects abrasive grains containing cerium oxide particles based on the amount of water adsorbed per unit area. According to this embodiment, it is possible to provide the use of slurry for polishing a surface to be polished that contains insulating material, and the use of slurry for polishing a surface to be polished that contains silicon oxide. According to this embodiment, it is possible to provide the use of slurry in the planarization process of a substrate surface, which is a manufacturing technology for semiconductor devices. According to this embodiment, it is possible to provide the use of slurry in the planarization process of STI insulating material, premetal insulating material, or interlayer insulating material.

[0020] (Abrasive grains) The slurry according to this embodiment contains abrasive grains, and the abrasive grains include cerium oxide particles (particles containing cerium oxide). The cerium oxide of the cerium oxide particles may contain tetravalent cerium or trivalent cerium.

[0021] The abrasive grains may contain particles other than cerium oxide particles. Examples of particles other than cerium oxide particles include silicon oxide (silica) particles, aluminum oxide (alumina) particles, silicon nitride particles, zirconium oxide (zirconia) particles (such as yttria-doped zirconia particles), titanium oxide (titania) particles, yttrium oxide (yttria) particles, silicon carbide particles, diamond particles, polymer particles, and the like.

[0022] The cerium oxide (cerium oxide particles) content may be within the following ranges based on the total mass of abrasive grains (total mass of abrasive grains contained in the slurry): From the viewpoint of easily obtaining a high polishing speed for insulating materials, the cerium oxide (cerium oxide particles) content may be 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, more than 50% by mass, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, 98% by mass or more, or 99% by mass or more. The slurry may be configured such that the abrasive grains contained in it are substantially composed of cerium oxide (cerium oxide particles) (a configuration in which the cerium oxide (cerium oxide particles) content is substantially 100% by mass based on the total mass of abrasive grains contained in the slurry).

[0023] Cerium oxide particles can be obtained, for example, by oxidizing a cerium compound. Methods for oxidizing the cerium compound include calcination and oxidation with hydrogen peroxide, etc. Calcination is preferable from the viewpoint of easily obtaining a high polishing rate for the insulating material and easily suppressing the decrease in polishing rate as polishing progresses. Examples of cerium compounds include cerium carbonate, cerium nitrate, cerium sulfate, and cerium oxalate. From the viewpoint of easily obtaining a high polishing rate for the insulating material and easily suppressing the decrease in polishing rate as polishing progresses, the cerium compound may be cerium carbonate, and the cerium oxide particles may contain oxides derived from cerium carbonate.

[0024] Cerium carbonate for obtaining cerium oxide particles can be obtained from natural minerals as raw materials, for example, by the following procedure. First, an ore containing rare earth elements including at least cerium (bastnasite ore, monazite, ankerite, etc.) is subjected to ore dressing to remove unnecessary gangue, thereby obtaining a rare earth concentrate (bastnasite concentrate, monazite concentrate, complex Chinese concentrate, etc.). Next, the rare earth concentrate is subjected to chemical treatment (alkali decomposition, sulfuric acid decomposition, hydroxide fractional precipitation method, etc.) to reduce insoluble components such as impurities, and then, if necessary, rare earth elements (neodymium, etc.) are reduced by solvent extraction to obtain a cerium-containing rare earth salt solution. Then, cerium carbonate can be obtained by mixing this cerium-containing rare earth salt solution and sodium carbonate. Such a manufacturing method of cerium carbonate is conveniently defined as the "extraction method".

[0025] By changing the above-mentioned sodium carbonate used in the "extraction method" to other salts, other cerium salts (cerium nitrate, cerium sulfate, cerium oxalate, etc.) can be synthesized. For example, cerium nitrate (e.g., cerium nitrate (III)) can be obtained by mixing a cerium-containing rare earth salt solution and sodium nitrate. Cerium carbonate can be obtained by reacting an aqueous solution of a cerium salt with a solution of a precursor having a carbonyl group. For example, cerium carbonate can be precipitated by reacting an aqueous solution of cerium nitrate (e.g., cerium nitrate (III)) with a solution of a precursor having a carbonyl group at a temperature of 80 to 100°C. As the precursor having a carbonyl group, urea or the like can be used. Such a manufacturing method of cerium carbonate is conveniently defined as the "carbonyl substitution method". The manufacturing method of cerium carbonate in the present embodiment may be either the "extraction method" or the "carbonyl substitution method" from the viewpoint of easily obtaining a high polishing rate of the insulating material and easily suppressing the decrease in the polishing rate as polishing progresses, and may be the "carbonyl substitution method".

[0026] The water adsorption amount per unit area of the cerium oxide particles is 0.032 mmol / m ２ or more. The water adsorption amount per unit area is 0.032 mmol / m ２As a result of the above, it is presumed that the chemical reactivity of the cerium oxide particles is improved, and the polishing speed of the insulating material is increased.

[0027] The amount of water adsorbed per unit area is the amount of water adsorbed when the relative pressure on the adsorption isotherm obtained at a temperature of 25°C with water as the adsorption medium is 0.85, and the BET specific surface area (S) when water is the adsorption medium. Ｗ It can be calculated by dividing by ). Specifically, the amount of water adsorbed per unit area can be obtained by the method described in the examples below.

[0028] The water adsorption rate per unit area is set at 0.034 mmol / m², from the viewpoint of improving the chemical reactivity of cerium oxide particles and thus improving the polishing speed of insulating materials. ２ Above, 0.036 mmol / m ２ Above, 0.038 mmol / m ２ Above, 0.040 mmol / m ２ Above, 0.040 mmol / m ２ Super, 0.041 mmol / m ２ Above, 0.042 mmol / m ２ Above, 0.043 mmol / m ２ Above, 0.044 mmol / m ２ Above, 0.045 mmol / m ２ Above, 0.046 mmol / m ２ Above, 0.047 mmol / m ２ Above or equal to 0.048 mmol / m² ２ The above is acceptable. The amount of water adsorbed per unit area is 0.060 mmol / m², from the viewpoint of easily improving the polishing speed of the insulating material. ２ Below, 0.058 mmol / m ２ Below, 0.056 mmol / m ２ Below, 0.054 mmol / m ２ Below, 0.052 mmol / m ２ Below, 0.050 mmol / m ２ Below, 0.050 mmol / m ２ Less than 0.049 mmol / m² ２ The following may apply. From these perspectives, the amount of water adsorbed per unit area is 0.032 to 0.060 mmol / m².２ , 0.032 to 0.054 mmol / m ２ ,0.032~0.050mmol / m ２ ,0.040~0.060mmol / m ２ ,0.040~0.050mmol / m ２ , 0.040 to 0.054 mmol / m ２ ,0.045-0.060mmol / m ２ , 0.045-0.054 mmol / m ２ , or 0.045 to 0.050 mmol / m ２ That's fine.

[0029] BET specific surface area (S) of cerium oxide particles when water is used as the adsorption medium Ｗ ) is chosen because increasing the surface area of ​​the cerium oxide particles increases the number of reaction sites on the surface of the cerium oxide particles, thereby improving chemical reactivity and making it easier to improve the polishing speed of the insulating material. ２ / g or more, 16.0m ２ / g or more, 17.0m ２ / g or more, or 18.0m ２ It may be 1 / g or more. Ｗ The reason for 30.0 m is that reducing the pore structure of the cerium oxide particles increases their physical strength, which in turn improves the polishing speed of insulating materials. ２ / g or less, 29.0m ２ / g or less, 28.0m ２ / g or less, 27.0m ２ / g or less, 26.0m ２ / g or less, or 25.0m ２ It may be less than or equal to / g. Ｗ It is 24.0m ２ / g or less, 23.0m ２ / g or less, 22.0m ２ / g or less, 21.0m ２ / g or less, 20.0m ２ / g or less, or 19.0m ２ It may be less than or equal to / g. From these perspectives, S Ｗ The range is 15.0 to 30.0 m. ２ / g, 15.0-25.0m ２ / g, 15.0 - 22.0 m ２ / g, 15.0 - 19.0 m ２ / g, 17.0 - 30.0 m ２ / g, 17.0 - 25.0 m ２ / g, 17.0 - 22.0 m ２ / g, 17.0 - 19.0 m ２ / g, 18.0 - 30.0 m ２ / g, 18.0 - 25.0 m ２ / g, 18.0 - 22.0 m ２ / g, or 18.0 - 19.0 m ２ / g may be. S Ｗ can be obtained by the method described in the examples below.

[0030] When nitrogen is used as the adsorption medium, the BET specific surface area (S Ｎ ) of the cerium oxide particles increases the physical strength of the cerium oxide particles due to the reduction of the pore structure of the cerium oxide particles, and from the viewpoint that the polishing rate of the insulating material is likely to be improved, it may be 35.0 m ２ / g or less, or 33.0 m ２ / g or less. S Ｎ is 30.0 m ２ / g or less, 28.0 m ２ / g or less, 26.0 m ２ / g or less, 24.0 m ２ / g or less, 22.0 m ２ / g or less, 21.0 m ２ / g or less, or 20.0 m ２ / g or less may be. S Ｎ is such that as the surface area of the cerium oxide particles increases, the number of reaction points on the surface of the cerium oxide particles increases, the chemical reactivity is further improved, and from the viewpoint that the polishing rate of the insulating material is likely to be improved, 10.0 m ２ / g or more, 12.0 m ２ / g or more, 14.0 m ２ / g or more, 15.0 m ２ / g or more, 15.0 m ２ / g, over 16.0 m ２ / g or more, 17.0 m ２ / g or more, 18.0 m ２ / g or more, 19.0 m ２ / g or more, 20.0 m ２ / g or more, 22.0 m ２ / g or more, 23.0 m ２ / g or more, 24.0 m ２ / g or more, 26.0 m ２ / g or more, 28.0 m ２ / g or more, 30.0 m ２ / g or more, 31.0 m ２ / g or more, or 32.0 m ２ / g or more may be. From these viewpoints, S Ｎ is 10.0 to 35.0 m ２ / g, 10.0 to 26.0 m ２ / g, 10.0 to 22.0 m ２ / g, 10.0 to 21.0 m ２ / g, 10.0 to 20.0 m ２ / g, 15.0 to 35.0 m ２ / g, 15.0 to 26.0 m ２ / g, 15.0 to 22.0 m ２ / g, 15.0 to 20.0 m ２ / g, 15.0 to 21.0 m ２ / g, 18.0 to 35.0 m ２ / g, 18.0 to 26.0 m ２ / g, 18.0 to 22.0 m ２ / g, 18.0 to 21.0 m ２ / g, or 18.0 to 20.0 m ２ / g may be. S Ｎ can be obtained by the method described in the examples below.

[0031] The BET diameter can be calculated from assuming that the primary particles of cerium oxide are spherical and S Ｎ and the true density ρ (= 7.2 g / cm ３ ) of the cerium oxide particles. Specifically, it can be calculated from the following formula. BET diameter = 6 / (ρ × S Ｎ )

[0032] The BET diameter of the cerium oxide particles may be 20.0 nm or larger, 22.0 nm or larger, 24.0 nm or larger, or 25.0 nm or larger, from the viewpoint of increasing the physical strength of the cerium oxide particles and improving the polishing speed of the insulating material. The BET diameter of the cerium oxide particles may be 38.0 nm or larger, 39.0 nm or larger, 40.0 nm or larger, greater than 40.0 nm, 41.0 nm or larger, or 41.5 nm or larger. The BET diameter may be 60.0 nm or less, 58.0 nm or less, 56.0 nm or less, 54.0 nm or less, 52.0 nm or less, 50.0 nm or less, less than 50.0 nm, 48.0 nm or less, 46.0 nm or less, 44.0 nm or less, 42.0 nm or less, 40.0 nm or less, 38.0 nm or less, 36.0 nm or less, 34.0 nm or less, 32.0 nm or less, 30.0 nm or less, 28.0 nm or less, or 26.0 nm or less, from the viewpoint of further improving the chemical reactivity of the cerium oxide particles and easily improving the polishing speed of the insulating material. From these perspectives, the BET diameter may be 20.0–60.0 nm, 20.0–50.0 nm, 20.0–45.0 nm, 38.0–60.0 nm, 38.0–50.0 nm, 38.0–45.0 nm, 40.0–60.0 nm, 40.0–50.0 nm, 40.0–45.0 nm, 41.5–60.0 nm, 41.5–50.0 nm, or 41.5–45.0 nm.

[0033] Based on the BJH method, a pore distribution curve can be obtained from the adsorption isotherm when nitrogen is used as the adsorption medium, with the horizontal axis representing pore diameter and the vertical axis representing differential pore volume. Specifically, the pore distribution curve can be obtained by the method described in the examples below.

[0034] The integrated value of the differential pore volume in the pore diameter range of 1.4 to 3.0 nm in the pore distribution curve of cerium oxide particles can be considered as the pore volume of pores with a diameter of 1.4 to 3.0 nm, and pores with a diameter of 1.4 to 3.0 nm are thought to represent pores within the cerium oxide particles. The integrated value of the differential pore volume in the pore diameter range of 1.4 to 3.0 nm in the pore distribution curve tends to increase the surface area of ​​the cerium oxide particles, and the increased number of reaction sites on the surface of the cerium oxide particles leads to improved chemical reactivity, which in turn improves the polishing rate of insulating materials. From this perspective, 3.1 × 10⁻⁶ －３cm ３ / g or more, 3.2×10 －３ cm ３ / g or more, 3.3×10 －３ cm ３ / g or more, 3.4×10 －３ cm ３ / g or more, 3.5×10 －３ cm ３ / g or more, 3.6×10 －３ cm ３ / g or more, 3.7×10 －３ cm ３ / g or more, 4.0×10 －３ cm ３ / g or more, 4.5×10 －３ cm ３ / g or more, 5.0×10 －３ cm ３ / g or more, 5.2×10 －３ cm ３ / g or more, 5.4×10 －３ cm ３ / g or more, 5.6×10 －３ cm ３ / g or more, 5.8×10 －３ cm ３ / g or more, or 6.0 x 10 －３ cm ３ It may be 1 / g or more. The integrated value of the differential pore volume in the pore diameter range of 1.4 to 3.0 nm in the pore distribution curve is 8.0 × 10⁻⁶, from the viewpoint that the physical strength of the cerium oxide particles is increased as the pore structure of the cerium oxide particles tends to decrease, and the polishing speed of the insulating material is easily improved. －３ cm ３ / g or less, 7.5×10 －３ cm ３ / g or less, 7.0×10 －３ cm ３ / g or less, 6.8×10 －３ cm ３ / g or less, 6.6×10 －３ cm ３ / g or less, 6.4×10 －３ cm ３ / g or less, 6.2×10 －３ cm ３ / g or less, or 6.0 x 10 －３ cm ３It may be less than or equal to / g. The cumulative value of the differential pore volume in the pore diameter range of 1.4 to 3.0 nm in the pore distribution curve is 5.0 × 10⁻⁶. －３ cm ３ / g or less, 4.8×10 －３ cm ３ / g or less, 4.6×10 －３ cm ３ / g or less, 4.5×10 －３ cm ３ / g or less, 4.4×10 －３ cm ３ / g or less, 4.2×10 －３ cm ３ / g or less, 4.0×10 －３ cm ３ / g or less, 4.0×10 －３ cm ３ Less than / g, 3.9 x 10 －３ cm ３ / g or less, 3.8×10 －３ cm ３ / g or less, or 3.7 × 10 －３ cm ３ It may be less than or equal to / g. From these viewpoints, the integrated value of the differential pore volume in the pore diameter range of 1.4 to 3.0 nm in the pore distribution curve is 3.1 × 10⁻⁶. －３ ~8.0 x 10 －３ cm ３ / g, 3.1 × 10 －３ ~7.0 x 10 －３ cm ３ / g, 3.1 × 10 －３ ~6.0 x 10 －３ cm ３ / g, 3.1 × 10 －３ ~5.0 x 10 －３ cm ３ / g, 3.1 × 10 －３ ~4.5 x 10 －３ cm ３ / g, 3.1 × 10 －３ ~4.0 x 10 －３ cm ３ / g, 3.3 × 10 －３ ~8.0 x 10 －３ cm ３ / g, 3.3 × 10 －３ ~7.0 x 10 －３ cm ３ / g, 3.3 × 10－３ ~6.0 x 10 －３ cm ３ / g, 3.3 × 10 －３ ~5.0 x 10 －３ cm ３ / g, 3.3 × 10 －３ ~4.5 x 10 －３ cm ３ / g, 3.3 × 10 －３ ~4.0 x 10 －３ cm ３ / g, 3.5 x 10 －３ ~8.0 x 10 －３ cm ３ / g, 3.5 x 10 －３ ~7.0 x 10 －３ cm ３ / g, 3.5 x 10 －３ ~6.0 x 10 －３ cm ３ / g, 3.5 x 10 －３ ~5.0 x 10 －３ cm ３ / g, 3.5 x 10 －３ ~4.5 x 10 －３ cm ３ / g, or 3.5 × 10 －３ ~4.0 x 10 －３ cm ３ It can be / g.

[0035] The integrated value of the differential pore volume in the pore diameter range of 10–30 nm in the pore distribution curve of cerium oxide particles can be considered as the pore volume of pores with a diameter of 10–30 nm, and these pores are thought to represent pores between cerium oxide particles. From the viewpoint of increasing the physical strength of the cerium oxide particles and improving the polishing speed of the insulating material, the integrated value of the differential pore volume in the pore diameter range of 10–30 nm in the pore distribution curve should be 0.045 cm². ３ / g or less, 0.040cm ３ / g or less, 0.038cm ３ / g or less, 0.036cm ３ / g or less, 0.034cm ３ / g or less, 0.032cm ３ / g or less, 0.031cm ３ / g or less, 0.030cm ３ / g or less, 0.028cm３ / g or less, 0.026cm ３ Less than or equal to 0.025 cm / g, or 0.025 cm ３ It may be less than or equal to / g. The cumulative value of the differential pore volume in the pore diameter range of 10 to 30 nm in the pore distribution curve is 0.024 cm³. ３ / g or less, 0.022cm ３ / g or less, 0.020cm ３ / g or less, 0.020cm ３ Less than 0.019 cm / g ３ Less than or equal to 0.018 cm² ３ It may be less than or equal to / g. The cumulative value of the differential pore volume in the pore diameter range of 10 to 30 nm in the pore distribution curve tends to suppress the aggregation of cerium oxide particles, and the chemical reactivity is further improved by increasing the number of reaction sites on the surface of the cerium oxide particles, which in turn improves the polishing rate of the insulating material, and is therefore set to 0.010 cm. ３ / g or more, 0.011cm ３ / g or more, 0.012cm ３ / g or more, 0.013cm ３ / g or more, 0.014cm ３ / g or more, 0.015cm ３ / g or more, 0.016cm ３ / g or more, 0.017cm ３ / g or more, 0.018cm ３ / g or more, 0.019cm ３ / g or more, 0.020cm ３ / g or more, 0.021cm ３ / g or more, 0.022cm ３ / g or more, 0.023cm ３ / g or more, 0.024cm ３ / g or more, or 0.025 cm ３ It may be greater than or equal to / g. From these viewpoints, the cumulative value of the differential pore volume in the pore diameter range of 10 to 30 nm in the pore distribution curve should be 0.010 to 0.040 cm³. ３ / g, 0.010–0.031cm ３ / g, 0.010–0.025cm ３ / g, 0.014–0.040 cm ３ / g, 0.014–0.031 cm ３ / g, 0.014–0.025 cm ３ / g, 0.014–0.020 cm ３ / g, 0.017–0.040 cm ３ / g, 0.017–0.031 cm ３ / g, 0.017–0.025cm ３ / g, or 0.017-0.020 cm ３ It can be / g.

[0036] The integrated value of the differential pore volume in the pore diameter range of 1.4 to 180 nm in the pore distribution curve of cerium oxide particles can be considered as the total pore volume. The integrated value of the differential pore volume in the pore diameter range of 1.4 to 180 nm in the pore distribution curve tends to suppress aggregation of cerium oxide particles, and the increased number of reaction sites on the surface of the cerium oxide particles leads to improved chemical reactivity and a higher polishing rate for insulating materials. Therefore, a value of 0.30 cm² is considered appropriate. ３ / g or less, 0.28cm ３ / g or less, 0.26cm ３ / g or less, 0.24cm ３ / g or less, 0.22cm ３ / g or less, 0.20cm ３ / g or less, 0.18cm ３ / g or less, 0.16cm ３ Less than or equal to 0.15 cm / g, or 0.15 cm ３ It may be less than or equal to / g. The cumulative value of the differential pore volume in the pore diameter range of 1.4 to 180 nm in the pore distribution curve is 0.15 cm³. ３ Less than 0.14 cm / g ３ / g or less, 0.13cm ３ / g or less, or 0.12 cm ３ It may be less than or equal to / g. The integrated value of the differential pore volume in the pore diameter range of 1.4 to 180 nm in the pore distribution curve should be 0.12 cm, from the viewpoint of increasing the physical strength of the cerium oxide particles and improving the polishing rate of the insulating material. ３ / g or more, 0.12cm ３ / g, 0.13cm ３ / g or more, 0.14cm ３ / g or more, or 0.15cm ３It may be greater than or equal to / g. From these viewpoints, the cumulative value of the differential pore volume in the pore diameter range of 1.4 to 180 nm in the pore distribution curve should be 0.12 to 0.30 cm². ３ / g, 0.12-0.20cm ３ / g, 0.12–0.16cm ３ / g, 0.12cm ３ / g or more 0.15cm ３ Less than 1g, 0.12-0.14cm ３ / g, 0.12cm ３ / g over 15cm ３ Less than 1g, or 12cm ３ / g over 0.14cm ３ It may be less than or equal to / g.

[0037] Water adsorption amount per unit area, S Ｗ S Ｎ Methods for adjusting the BET diameter and the integrated value of the differential pore volume in a specific range of pore diameters in the pore distribution curve include changing the composition of the raw material; changing the method of preparing the raw material; changing the firing temperature, firing time, etc. in the firing method; and changing the grinding method, conditions, etc. These methods may be used individually or in combination. For example, by lowering the firing temperature in the firing method, the amount of water adsorbed per unit area can be increased, S Ｎ It can be made larger.

[0038] The cerium oxide particles to be measured to obtain the amount of water adsorbed per unit area of ​​the cerium oxide particles may be recovered by drying the slurry (to dryness), or by separating and removing components other than cerium oxide particles from the dried material. If the amount of water adsorbed per unit area of ​​the cerium oxide particles does not change during slurry preparation, the cerium oxide particles to be measured may be the cerium oxide particles before mixing with other components such as water.

[0039] The volume-average particle size of the abrasive grains, or the volume-average particle size of the cerium oxide particles, may be within the following ranges. From the viewpoint of easily obtaining a high polishing speed for insulating materials, the volume-average particle size may be 100 nm or more, 150 nm or more, 175 nm or more, greater than 175 nm, 180 nm or more, 200 nm or more, 220 nm or more, 230 nm or more, 240 nm or more, 245 nm or more, 250 nm or more, 255 nm or more, or 260 nm or more. From the viewpoint of easily reducing scratches caused by polishing, the volume-average particle size may be 600 nm or less, 550 nm or less, less than 550 nm, 500 nm or less, 450 nm or less, 400 nm or less, 350 nm or less, 320 nm or less, 300 nm or less, 295 nm or less, 290 nm or less, 285 nm or less, 280 nm or less, 275 nm or less, 270 nm or less, or 265 nm or less. From these perspectives, the volume-average particle size may be 100-600 nm, 100-500 nm, 100-400 nm, 100-300 nm, 100-280 nm, 150-600 nm, 150-500 nm, 150-400 nm, 150-300 nm, 150-280 nm, 200-600 nm, 200-500 nm, 200-400 nm, 200-300 nm, 200-280 nm, 250-600 nm, 250-500 nm, 250-400 nm, 250-300 nm, or 250-280 nm.

[0040] The volume-average particle size refers to the MV (Mean Volume Diameter) value measured with a laser diffraction particle size analyzer, and can be measured, for example, by the method described in the examples below. The volume-average particle size may be measured by diluting the slurry with water to adjust the abrasive content or cerium oxide particle content to an appropriate level. For example, in the case of the product "SYNC" manufactured by Microtrac-Bell Corporation, the content may be adjusted to a DV (Diffraction Volume) value of 0.0010 to 0.0150. The DV value is a concentration index that utilizes the total amount of scattered light from the sample received by the detector, and tends to increase as the abrasive content or cerium oxide particle content in the sample increases. If a slurry containing abrasive grains (abrasive grains containing cerium oxide particles), additives, and water is stored separately as a first liquid containing abrasive grains and water, and a second liquid containing additives and water, the abrasive grain content may be adjusted to an appropriate level by diluting the first liquid with water, and the volume-average particle size may be measured.

[0041] Methods for adjusting the volume-average particle size include adjusting the composition of the raw materials, the manufacturing method, the firing temperature, the firing time, etc.; grinding; classification; and filtration. Grinding, classification, and filtration may be performed on abrasive grains or cerium oxide particles, or on the raw materials for obtaining cerium oxide particles (cerium compounds such as cerium carbonate).

[0042] The abrasive content in the slurry, or the cerium oxide particle content in the slurry, may be within the following ranges based on the total mass of the slurry. The content may be 0.01% by mass or more, 0.05% by mass or more, 0.10% by mass or more, 0.15% by mass or more, 0.30% by mass or more, 0.50% by mass or more, 0.80% by mass or more, 1.00% by mass or more, 1.20% by mass or more, 1.50% by mass or more, 1.80% by mass or more, or 2.00% by mass or more, from the viewpoint of easily obtaining a high polishing speed for insulating materials. The content may be 20.00% by mass or less, 15.00% by mass or less, 10.00% by mass or less, 8.00% by mass or less, 5.00% by mass or less, 4.50% by mass or less, 4.00% by mass or less, 3.50% by mass or less, 3.00% by mass or less, 2.50% by mass or less, or 2.00% by mass or less, from the viewpoint of suppressing particle aggregation and making it less likely to scratch the polished surface. From these perspectives, the content may be 0.01 to 20.00 mass%, 0.01 to 10.00 mass%, 0.01 to 5.00 mass%, 0.10 to 20.00 mass%, 0.10 to 10.00 mass%, 0.10 to 5.00 mass%, 0.50 to 20.00 mass%, 0.50 to 10.00 mass%, 0.50 to 5.00 mass%, 1.00 to 20.00 mass%, 1.00 to 10.00 mass%, or 1.00 to 5.00 mass%.

[0043] (Water) There are no particular restrictions on the type of water used, but examples include deionized water and ultrapure water. The water content is not particularly limited and may be the remainder of the slurry after removing the content of other components.

[0044] The water content in the slurry may be within the following ranges, based on the total mass of the slurry, from the viewpoint of obtaining a high polishing speed for the insulating material while suppressing a decrease in polishing speed as polishing progresses. The water content may be 50% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 93% by mass or more, 95% by mass or more, 96% by mass or more, or 97% by mass or more. The water content may be less than 100% by mass, 99% by mass or less, or 98% by mass or less. From these viewpoints, the water content may be 50% by mass or more and less than 100% by mass, 50 to 99% by mass, 50 to 98% by mass, 80% by mass or more and less than 100% by mass, 80 to 99% by mass, 80 to 98% by mass, 90% by mass or more and less than 100% by mass, 90 to 99% by mass, or 90 to 98% by mass.

[0045] (Additives) The slurry according to this embodiment may or may not contain any additives. Examples of optional additives include polar solvents (ethanol, acetone, etc.), materials having carboxyl groups (excluding compounds corresponding to polyoxyalkylene compounds or water-soluble polymers), polyoxyalkylene compounds, water-soluble polymers, oxidizing agents (e.g., hydrogen peroxide), and dispersants (e.g., phosphate-based inorganic salts).

[0046] Materials containing a carboxyl group include monocarboxylic acids such as acetic acid, propionic acid, butyric acid, and valeric acid; hydroxy acids such as lactic acid, malic acid, and citric acid; dicarboxylic acids such as malonic acid, succinic acid, fumaric acid, and maleic acid; and amino acids such as arginine, histidine, and lysine.

[0047] Examples of polyoxyalkylene compounds include polyalkylene glycols and polyoxyalkylene derivatives.

[0048] Examples of polyalkylene glycols include polyethylene glycol, polypropylene glycol, and polybutylene glycol.

[0049] Polyoxyalkylene derivatives are, for example, compounds obtained by introducing a functional group or substituent to a polyalkylene glycol, or compounds obtained by adding a polyalkylene oxide to an organic compound. Examples of functional groups or substituents include alkyl ether groups, alkylphenyl ether groups, phenyl ether groups, styrene-phenyl ether groups, glyceryl ether groups, alkylamine groups, fatty acid ester groups, glycol ester groups, and the like. Examples of polyoxyalkylene derivatives include polyoxyethylene alkyl ethers, polyoxyethylene bisphenol ethers (e.g., BA Glycol series from Nippon Emulsifier Co., Ltd.), polyoxyethylene styrene-phenyl ethers (e.g., Emulgen series from Kao Corporation), polyoxyethylene alkylphenyl ethers (e.g., Neugen EA series from Daiichi Kogyo Seiyaku Co., Ltd.), polyoxyalkylene polyglyceryl ethers (e.g., SC-E series and SC-P series from Sakamoto Pharmaceutical Co., Ltd.), polyoxyethylene sorbitan fatty acid esters (e.g., Sorgen TW series from Daiichi Kogyo Seiyaku Co., Ltd.), polyoxyethylene fatty acid esters (e.g., Emanon series from Kao Corporation), polyoxyethylene alkylamines (e.g., Amiradin D from Daiichi Kogyo Seiyaku Co., Ltd.), and other compounds to which polyalkylene oxides have been added (e.g., Surfinol 465 from Nisshin Chemical Industry Co., Ltd.; TMP series from Nippon Emulsifier Co., Ltd.).

[0050] Water-soluble polymers have the effect of adjusting the dispersion stability of abrasive particles. A "water-soluble polymer" is defined as a polymer that dissolves at a rate of 0.1 g or more per 100 g of water. Polymers that fall under the category of polyoxyalkylene compounds are not included in the definition of a "water-soluble polymer."

[0051] Examples of water-soluble polymers include polycarboxylic acids such as polyacrylic acid and polymaleic acid; acrylic polymers such as polyacrylamide and polydimethylacrylamide; polysaccharides such as carboxymethylcellulose, agar, curdlan, dextrin, cyclodextrin, and pullulan; vinyl polymers such as polyvinyl alcohol, polyvinylpyrrolidone, and polyacrolein; and glycerin polymers such as polyglycerin and polyglycerin derivatives.

[0052] The content of the water-soluble polymer may be within the following ranges based on the total mass of the slurry, from the viewpoint of easily obtaining the effect of adding the water-soluble polymer while suppressing the settling of abrasive grains. The content of the water-soluble polymer may be 0.001% by mass or more, 0.005% by mass or more, 0.010% by mass or more, 0.020% by mass or more, 0.030% by mass or more, 0.040% by mass or more, 0.050% by mass or more, 0.060% by mass or more, 0.070% by mass or more, or 0.075% by mass or more. The content of the water-soluble polymer may be 10.000 mass% or less, 8.000 mass% or less, 6.000 mass% or less, 5.000 mass% or less, 3.000 mass% or less, 1.000 mass% or less, 0.500 mass% or less, 0.300 mass% or less, 0.100 mass% or less, 0.080 mass% or less, or 0.075 mass% or less. From these perspectives, the content of the soluble polymer may be 0.001 to 10.000% by mass, 0.001 to 1.000% by mass, 0.001 to 0.500% by mass, 0.001 to 0.100% by mass, 0.010 to 10.000% by mass, 0.010 to 1.000% by mass, 0.010 to 0.500% by mass, 0.010 to 0.100% by mass, 0.030 to 10.000% by mass, 0.030 to 1.000% by mass, 0.030 to 0.500% by mass, 0.030 to 0.100% by mass, 0.050 to 10.000% by mass, 0.050 to 1.000% by mass, 0.050 to 0.500% by mass, or 0.050 to 0.100% by mass.

[0053] (pH) The pH of the slurry according to this embodiment may be within the following range. From the viewpoint of easily obtaining a high polishing rate for the insulating material, the pH may be 1.00 or higher, 1.50 or higher, 2.00 or higher, 2.50 or higher, 3.00 or higher, greater than 3.00, 3.50 or higher, greater than 3.50, 4.00 or higher, greater than 4.00, 4.10 or higher, 4.20 or higher, 4.30 or higher, 4.40 or higher, 4.50 or higher, greater than 4.50, 4.60 or higher, 4.70 or higher, or 4.80 or higher. The pH may be 7.00 or less, less than 7.00, 6.50 or less, less than 6.50, 6.00 or less, less than 6.00, 5.50 or less, less than 5.50, 5.00 or less, less than 5.00, 4.90 or less, 4.85 or less, 4.80 or less, 4.75 or less, 4.70 or less, 4.65 or less, 4.60 or less, 4.55 or less, 4.50 or less, less than 4.50, 4.45 or less, 4.40 or less, 4.35 or less, 4.30 or less, 4.25 or less, or 4.20 or less, from the viewpoint of improving the storage stability of the slurry. From these perspectives, the pH may be 1.00–7.00, 1.00–6.00, 1.00–5.00, 1.00–4.50, 2.00–7.00, 2.00–6.00, 2.00–5.00, 2.00–4.50, 3.00–7.00, 3.00–6.00, 3.00–5.00, 3.00–4.50, 4.00–7.00, 4.00–6.00, 4.00–5.00, or 4.00–4.50. The pH of the slurry is defined as the pH at a liquid temperature of 25°C.

[0054] The pH of the slurry can be adjusted by acidic components such as inorganic acids and organic acids; and alkaline components such as ammonia, sodium hydroxide, tetramethylammonium hydroxide (TMAH), imidazole, and alkanolamines. A buffering agent may be added to stabilize the pH, or a buffer solution (a solution containing a buffering agent) may be added. Examples of buffer solutions include acetate buffers and phthalate buffers.

[0055] The pH of the slurry according to this embodiment can be measured using a pH meter (for example, model PHL-40 manufactured by Toa DKK Corporation). For example, after calibrating the pH meter at two points using phthalate pH buffer (pH: 4.01) and neutral phosphate pH buffer (pH: 6.86) as standard buffers, the pH meter electrode can be placed in the slurry, and the value after stabilization for two minutes or more can be measured as the pH of the slurry. The liquid temperature of both the standard buffer and the slurry should be 25°C.

[0056] (Storage Method) When the slurry according to this embodiment contains any of the above-mentioned additives, the slurry according to this embodiment may be stored in a single-liquid state containing abrasive grains, additives, and water, or it may be stored as a multi-liquid slurry (slurry set) in which the components of the slurry are divided into a first liquid and a second liquid so that the slurry is formed by mixing a first liquid containing abrasive grains and water with a second liquid containing additives and water. The slurry according to this embodiment may be in a single-liquid state containing abrasive grains, additives, and water, or it may be the first liquid in a multi-liquid slurry. The second liquid may contain at least one of the additives, and the first liquid may contain the same or different additive as the additive in the second liquid. The components of the slurry may be stored in three or more liquids.

[0057] In the multi-liquid slurry described above, the first liquid and the second liquid are mixed immediately before or during polishing to prepare the slurry. The single-liquid slurry can be stored as a storage liquid with reduced water content and may be diluted with water before use during polishing. In the multi-liquid slurry, the first liquid and the second liquid can be stored as a storage liquid with reduced water content and may be diluted with water before use during polishing.

[0058] <Polishing Method> The polishing method according to this embodiment (polishing method for a substrate, etc.) comprises a polishing step of polishing the surface to be polished (the surface to be polished of a substrate, etc.) using the slurry according to this embodiment. The slurry in the polishing step may be a slurry obtained by mixing the first liquid and the second liquid in the multi-liquid slurry described above.

[0059] In the polishing process, for example, the insulating material of a substrate having an insulating material may be pressed against the polishing pad (polishing cloth) of a polishing platen, and the slurry according to this embodiment may be supplied between the material to be polished and the polishing pad, and the substrate and the polishing platen may be moved relative to each other to polish the surface of the insulating material. In the polishing process, for example, at least a portion of the insulating material is removed by polishing.

[0060] Examples of substrates to be polished include substrates to be polished. Examples of substrates to be polished include substrates used in semiconductor device manufacturing (e.g., semiconductor substrates on which STI patterns, gate patterns, wiring patterns, etc., are formed) on which an insulating material is formed. Examples of insulating materials include silicon oxide. The insulating material may be a single material or multiple materials. If multiple materials are exposed on the surface to be polished, they can be considered as insulating materials. The insulating material may be in the form of a film (insulating film) or a silicon oxide film.

[0061] By using the slurry according to this embodiment, the surface irregularities of the insulating material (e.g., silicon oxide) formed on the substrate can be polished to remove excess material, thereby eliminating surface irregularities and obtaining a smooth surface across the entire surface of the insulating material.

[0062] In the polishing method according to this embodiment, a general polishing apparatus can be used, which includes a holder capable of holding a substrate having a surface to be polished, and a polishing platen to which a polishing pad can be attached. The holder and the polishing platen may each be equipped with a motor or the like that which allows the rotation speed to be changed.

[0063] As polishing pads, general nonwoven fabrics, foams, and non-foamed materials can be used. As materials for polishing pads, resins such as polyurethane, acrylic resin, polyester, acrylic-ester copolymer, polytetrafluoroethylene, polypropylene, polyethylene, poly-methylpentene, cellulose, cellulose ester, polyamide (e.g., nylon (trademark name) and aramid), polyimide, polyimidamide, polysiloxane copolymer, oxirane compounds, phenolic resin, polystyrene, polycarbonate, and epoxy resin can be used. From the viewpoint of easily obtaining excellent polishing speed and flatness, the material of the polishing pad may be at least one selected from the group consisting of foamed polyurethane and non-foamed polyurethane. The polishing pad may be grooved to allow slurry to accumulate.

[0064] There are no restrictions on the polishing conditions, but the upper limit of the rotation speed of the polishing platen is 200 mins to prevent the base material from flying off. －１ (min －１ The pressure (rpm) may be less than or equal to 100 kPa, and the upper limit of the polishing pressure (processing load) applied to the substrate may be 100 kPa or less, from the viewpoint of easily suppressing the occurrence of polishing scratches. During polishing, slurry may be continuously supplied to the polishing pad by a pump or the like. There is no limit to the amount of slurry supplied in this case, but the surface of the polishing pad may always be covered with slurry.

[0065] The slurry and polishing method according to this embodiment may be used to polish a surface containing silicon oxide. The slurry and polishing method according to this embodiment can be suitably used for forming STIs and for high-speed polishing of interlayer insulating materials. Such silicon oxide may have some of its constituent elements substituted with carbon atoms, nitrogen atoms, etc.

[0066] The slurry and polishing method according to this embodiment can also be used for polishing premetallic insulating materials. Examples of premetallic insulating materials include silicon oxide, phosphorus-silicate glass, boron-phosphorus-silicate glass, silicon oxyfluoride, amorphous carbon fluoride, and the like.

[0067] The slurry and polishing method according to this embodiment can be applied to materials other than insulating materials such as silicon oxide. Examples of such materials include high dielectric constant materials such as Hf-based, Ti-based, and Ta-based oxides; semiconductor materials such as silicon, amorphous silicon, SiC, SiGe, Ge, GaN, GaP, GaAs, and organic semiconductors; phase change materials such as GeSbTe; inorganic conductive materials such as ITO; and polymer resin materials such as polyimide-based, polybenzoxazole-based, acrylic-based, epoxy-based, and phenol-based materials.

[0068] The slurry and polishing method according to this embodiment can be applied not only to film-like polishing targets, but also to various substrates made of glass, silicon, SiC, SiGe, Ge, GaN, GaP, GaAs, sapphire, plastic, and the like.

[0069] The slurry and polishing method according to this embodiment can be used not only for the manufacture of semiconductor devices, but also for the manufacture of image display devices such as TFTs and organic ELs; optical components such as photomasks, lenses, prisms, optical fibers, and single-crystal scintillators; optical elements such as optical switching elements and optical waveguides; light-emitting elements such as solid-state lasers and blue laser LEDs; and magnetic storage devices such as magnetic disks and magnetic heads.

[0070] <Manufacturing Method, etc.> The manufacturing method of a component according to this embodiment includes a component manufacturing step of obtaining a component using a workpiece (substrate) polished by the polishing method according to this embodiment. The component according to this embodiment is a component obtained by the manufacturing method of a component according to this embodiment. The component according to this embodiment is not particularly limited, but may be an electronic component (for example, a semiconductor component such as a semiconductor package), a wafer (for example, a semiconductor wafer), or a chip (for example, a semiconductor chip). As one embodiment of the manufacturing method of a component according to this embodiment, the manufacturing method of an electronic component according to this embodiment obtains an electronic component using a workpiece polished by the polishing method according to this embodiment. As one embodiment of the manufacturing method of a component according to this embodiment, the manufacturing method of a semiconductor component according to this embodiment obtains a semiconductor component (for example, a semiconductor package) using a workpiece polished by the polishing method according to this embodiment. The manufacturing method of a component according to this embodiment may include a polishing step of polishing the workpiece using the polishing method according to this embodiment before the component manufacturing step.

[0071] As one aspect of the component manufacturing process according to this embodiment, the component manufacturing process may include a piece-forming step in which the member to be polished (substrate) polished by the polishing method according to this embodiment is divided into individual pieces. The piece-forming step may be, for example, a step of dicing a wafer (e.g., a semiconductor wafer) polished by the polishing method according to this embodiment to obtain a chip (e.g., a semiconductor chip). As one aspect of the component manufacturing process according to this embodiment, the electronic component manufacturing process according to this embodiment may include a step of obtaining an electronic component (e.g., a semiconductor component) by dividing the member to be polished by the polishing method according to this embodiment into individual pieces. As one aspect of the component manufacturing process according to this embodiment, the semiconductor component manufacturing process according to this embodiment may include a step of obtaining a semiconductor component (e.g., a semiconductor package) by dividing the member to be polished by the polishing method according to this embodiment into individual pieces.

[0072] The method for manufacturing a part according to this embodiment may include, as one aspect of the part manufacturing process, a connection step of connecting (for example, electrically connecting) a member to be polished (substrate) polished by the polishing method according to this embodiment to another connected body. The connected body connected to the member to be polished by the polishing method according to this embodiment is not particularly limited and may be the member to be polished by the polishing method according to this embodiment, or it may be a connected body different from the member to be polished by the polishing method according to this embodiment. In the connection step, the member to be polished and the connected body may be directly connected (connected in a state where the member to be polished and the connected body are in contact), or they may be connected via another member (such as a conductive member). The connection step can be performed before the individualization step, after the individualization step, or before and after the individualization step.

[0073] The connection step may be a step of connecting the surface of the member to be polished, which has been polished by the polishing method according to this embodiment, to the connected body, or a step of connecting the connecting surface of the member to be polished, which has been polished by the polishing method according to this embodiment, to the connecting surface of the connected body. The connecting surface of the member to be polished may be the surface of the member to be polished, which has been polished by the polishing method according to this embodiment. By the connection step, a connected body comprising the member to be polished and the connected body can be obtained. In the connection step, if the connecting surface of the member to be polished has a metal part, the connected body may be brought into contact with the metal part. In the connection step, if the connecting surface of the member to be polished has a metal part and the connecting surface of the connected body has a metal part, the metal parts may be brought into contact with each other. The metal part may contain copper.

[0074] The device according to this embodiment (for example, an electronic device such as a semiconductor device) comprises a member to be polished by the polishing method according to this embodiment, and at least one selected from the group consisting of the component according to this embodiment.

[0075] The present disclosure will be described in detail below based on examples, but the present disclosure is not limited to the following examples.

[0076] <Preparation of the slurry> (Example 1) Based on the "carbonyl substitution method" described above, a cerium carbonate precipitate was generated by mixing a 0.1 mol / L aqueous solution of cerium(III) nitrate and a 7.8 mol / L aqueous solution of urea in a volume ratio of 6:1 while maintaining the temperature at 95°C. This precipitate was filtered and dried to obtain cerium carbonate powder (raw material). This cerium carbonate powder was placed in an alumina container and calcined in an oven "HPM-2N" manufactured by AS ONE Corporation at a calcination temperature of 800°C in air for 1 hour to obtain a white powder. Phase identification of this powder was performed by XRD and confirmed to be cerium oxide powder.

[0077] The cerium oxide powder was crushed in a mortar and then passed through a sieve with a mesh size of 450 μm to obtain a pulverized product. This pulverized product, pure water, and acetic acid were mixed in a mass ratio of 20.00:79.94:0.06 to obtain a mixture. This mixture was then pulverized using a wet atomization device "Starburst Lab HJP-25005" (pressure 245 MPa) manufactured by Sugino Machine Co., Ltd. until the volume average particle size was 400-450 nm to obtain a dispersion. This dispersion was centrifuged for 60 seconds using a centrifugal separator "himac CR7" (rotation speed 2000 rpm) manufactured by Hitachi Koki Co., Ltd., and the liquid remaining at the top of the container after centrifugation was obtained as a dispersion containing cerium oxide particles. Subsequently, the cerium oxide particles were recovered from this dispersion.

[0078] A polishing slurry was obtained by mixing these cerium oxide particles (abrasive grains), pure water, and polyglycerin (manufactured by Sakamoto Pharmaceutical Co., Ltd., product name: Polyglycerin #750) in a mass ratio of 2.000:97.925:0.075.

[0079] (Example 2) Polishing slurry was obtained in the same manner as in Example 1, except that the firing temperature was changed to 700°C.

[0080] (Comparative Example 1) Based on the "extraction method" described above, a cerium carbonate precipitate was produced by mixing a 0.1 mol / L aqueous solution of cerium(III) sulfate and a 0.1 mol / L aqueous solution of sodium carbonate in a volume ratio of 1:2 while maintaining the temperature at 95°C. This precipitate was filtered and dried to obtain cerium carbonate powder (raw material). This cerium carbonate powder was placed in an alumina container and calcined in an oven "HPM-2N" manufactured by AS ONE Corporation at a calcination temperature of 800°C in air for 1 hour to obtain a white powder. Phase identification of this powder was performed by XRD and confirmed to be cerium oxide powder.

[0081] The cerium oxide powder was crushed in a mortar and then passed through a sieve with a mesh size of 450 μm to obtain a pulverized product. This pulverized product, pure water, and acetic acid were mixed in a mass ratio of 20.00:79.94:0.06 to obtain a mixture. This mixture was then pulverized using a wet atomization device "Starburst Lab HJP-25005" (pressure 245 MPa) manufactured by Sugino Machine Co., Ltd. until the volume average particle size was 400-450 nm to obtain a dispersion. This dispersion was centrifuged for 60 seconds using a centrifugal separator "himac CR7" (rotation speed 2000 rpm) manufactured by Hitachi Koki Co., Ltd., and the liquid remaining at the top of the container after centrifugation was obtained as a dispersion containing cerium oxide particles. Subsequently, the cerium oxide particles were recovered from this dispersion.

[0082] A polishing slurry was obtained by mixing these cerium oxide particles (abrasive grains), pure water, and polyglycerin (manufactured by Sakamoto Pharmaceutical Co., Ltd., product name: Polyglycerin #750) in a mass ratio of 2.000:97.925:0.075.

[0083] <BET specific surface area and water adsorption amount per unit area when water is used as the adsorption medium> Each of the slurries described above was centrifuged at a centrifugal acceleration of 4700 G for 30 minutes to settle the abrasive particles, and then the supernatant was removed. Next, abrasive powder was obtained by vacuum drying at room temperature (25°C) for 24 hours, and then the abrasive powder was vacuum dried at 250°C for 15 hours. Next, approximately 0.6 g of abrasive powder was weighed, and using a BET specific surface area measuring device (Micromeritix, product name: 3Flex), the measurement items were specific surface area and pore distribution, and measurements were taken using constant volume gas adsorption with water as the adsorption medium at a temperature of 25°C and a relative pressure of 0.85 to 0.90 to obtain the adsorption isotherm when water is used as the adsorption medium. From the obtained adsorption isotherm, the BET specific surface area (S) when water is used as the adsorption medium was obtained by water vapor adsorption in the region of relative pressure of 0.3 or less. Ｗ ) was obtained. Also, the amount of adsorption at a relative pressure of 0.85 on the adsorption isotherm when water is used as the adsorption medium was S Ｗ By dividing by [a certain factor], the amount of water adsorbed per unit area was obtained. The measurement results are shown in Table 1.

[0084] <BET specific surface area, BET diameter, and pore distribution curves when nitrogen is used as the adsorption medium> Each of the slurries described above was centrifuged at a centrifugal acceleration of 4700 G for 30 minutes to settle the abrasive particles, and then the supernatant was removed. Next, abrasive powder was obtained by vacuum drying at room temperature (25°C) for 24 hours, and then the abrasive powder was vacuum dried at 100°C for 1 hour. Next, 0.3 to 0.4 g of the abrasive powder was weighed, and the BET specific surface area was measured using a BET specific surface area measuring device (Quantachrome Instruments, product name: QuadraSorb EVO) with liquid nitrogen (77 K) as the adsorption medium by gas adsorption method at a temperature of 77 K until the relative pressure reached 0.99, thereby obtaining the adsorption isotherm when nitrogen was used as the adsorption medium. From the obtained adsorption isotherms, the BET specific surface area (S) of the abrasive grains was determined by the multipoint BET method in the relative pressure region of 0.049 to 0.30. Ｎ ) was obtained. Also, the obtained S Ｎ and the true density of cerium oxide particles (7.2 g / cm³) ３The BET diameter was calculated from the following. Furthermore, a pore distribution curve was obtained from the adsorption isotherm when nitrogen was used as the adsorption medium, based on QuadraWin (version 7.1) attached to the BET specific surface area measuring device, with the horizontal axis representing pore diameter and the vertical axis representing differential pore volume. From the obtained pore distribution curve, the integrated value of the differential pore volume in the range of pore diameter 1.4 to 3.0 nm, the integrated value of the differential pore volume in the range of pore diameter 10 to 30 nm, and the integrated value of the differential pore volume in the range of pore diameter 1.4 to 180 nm were calculated. The measurement results are shown in Table 1.

[0085] <Volume-average particle size> Appropriate amounts of each of the above-mentioned slurries were placed into a laser diffraction particle size analyzer (Microtrac-Bell Co., Ltd., product name "SYNC", particle refractive index: 2.20) to obtain the MV (volume-average particle size) of the abrasive grains. The measurement results are shown in Table 1.

[0086] <pH of the slurry> The pH (at 25°C) of each slurry described above was measured using a PHL-40 measuring device manufactured by Toa DKK Corporation. The measurement results are shown in Table 1.

[0087] <CMP Evaluation> Using the slurries described above, a CMP evaluation was conducted under the following conditions.

[0088] [CMP Polishing Conditions] Polishing equipment: Reflexion LK CMP (Applied Materials) Slurry flow rate: 250 mL / min Substrate to be polished: A blanket wafer without a pattern was used, which had a 2 μm thick silicon oxide film formed by plasma CVD on a silicon substrate. Polishing pad: Foamed polyurethane resin with closed cells (Nitta DuPont, model IK4250H) Polishing pressure: 27.6 kPa (4 psi) Rotation speed of substrate to be polished and polishing platen: Substrate to be polished / polishing platen = 117 / 123 rpm Polishing time: 20 seconds and 50 seconds Wafer cleaning: After CMP treatment, the wafer was washed with water while applying ultrasound, and then dried with a spin dryer.

[0089] The polishing speeds for 20-second and 50-second polishing were determined for the silicon oxide film polished and cleaned under the above conditions using the following formula. The results are shown in Table 1. The difference in silicon oxide film thickness before and after polishing was determined using an optical interference film thickness analyzer (NOVA Corporation, product name: Nova i500). Polishing speed = Difference in silicon oxide film thickness before and after polishing [nm] / Polishing time [min]

[0090] Using the polishing speeds for 20 seconds and 50 seconds as described above, the polishing speed retention rate was calculated using the following formula. The results are shown in Table 1. Polishing speed retention rate [%] = (Polishing speed for 50 seconds [nm / min] / Polishing speed for 20 seconds [nm / min]) × 100

[0091]

Claims

1. Contains abrasive particles and water, wherein the abrasive particles contain cerium oxide particles, and the amount of water adsorbed per unit area of ​​the cerium oxide particles is 0.032 mmol / m². ２ That's all, Slari.

2. The water adsorption amount is 0.060 mmol / m². ２ The slurry described in claim 1 is as follows:

3. The BET specific surface area of ​​the cerium oxide particles when water is used as the adsorption medium is 15.0 m². ２ The slurry according to claim 1, wherein the amount is 1 / g or more.

4. The BET specific surface area of ​​the cerium oxide particles when nitrogen is used as the adsorption medium is 10.0 to 35.0 m². ２ The slurry according to claim 1, wherein the amount is / g.

5. The slurry according to claim 1, wherein the BET diameter of the cerium oxide particles is 20.0 to 60.0 nm.

6. The cumulative value of the differential pore volume in the pore diameter range of 1.4 to 3.0 nm in the pore distribution curve of the cerium oxide particles is 3.1 × 10⁻⁶. －３ cm ３ The slurry according to claim 1, wherein the amount is 1 / g or more.

7. The slurry according to claim 1, wherein the volume-average particle size of the cerium oxide particles is 150 to 300 nm.

8. The slurry according to claim 1, wherein the abrasive content is 0.01 to 10.00% by mass.

9. The slurry according to claim 1, wherein the pH is 1.00 to 7.

00.

10. A polishing method comprising the step of polishing a member to be polished using a slurry described in any one of claims 1 to 9.

11. The polishing method according to claim 10, wherein the member to be polished contains silicon oxide.

12. A method for manufacturing a part, comprising the step of obtaining a part using the member to be polished by the polishing method described in claim 10.

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