Polishing liquid, polishing liquid set, polishing method, and defect inhibition method

Abstract

A polishing liquid containing abrasive grains, a first nitrogen-containing compound, a second nitrogen-containing compound, and water, the first nitrogen-containing compound including at least one selected from the group consisting of (I) a compound having an aromatic ring having 1 nitrogen atom in the ring and a hydroxyl group, (II) a compound having an aromatic ring having 1 nitrogen atom in the ring and a functional group containing a nitrogen atom, (III) a compound having a 6-membered ring having 2 nitrogen atoms in the ring, (IV) a compound having a benzene ring and a ring having a nitrogen atom in the ring, and (V) a compound having a benzene ring to which 2 or more functional groups containing a nitrogen atom are bonded, the second nitrogen-containing compound having an HLB value of 7 or more.

Description

TECHNICAL FIELD

[0001] The present application relates to a polishing liquid, a polishing liquid set, and a polishing method and a defect inhibiting method using the polishing liquid or the polishing liquid set. More specifically, the present application relates to a polishing liquid, a polishing liquid set, and a polishing method and a defect inhibiting method using the polishing liquid or the polishing liquid set, which are usable in a planarization process of a substrate surface as a manufacturing technique of a semiconductor element (particularly, a planarization process of an interlayer insulating film, a BPSG film (a silicon dioxide film doped with boron and phosphorus), and the like, a Shallow Trench Isolation (STI) formation process, and the like). BACKGROUND

[0002] In a manufacturing process of a ULSI (Ultra large-scale integrated) semiconductor element at present, a processing technique for high-density and miniaturization of a semiconductor element is under development. As one of the processing techniques, a planarization technique using CMP (Chemical Mechanical Polishing) is becoming a necessary technique in a planarization process of an interlayer insulating film and the like, an STI formation process, a plug formation process, an embedded metal wiring formation process (damascene process), and the like in a manufacturing process of a semiconductor element. The CMP process (planarization process using the CMP technique) generally polishes a polished material by supplying a polishing liquid for CMP between a polishing pad (polishing cloth) and the polished material while polishing the polished material.

[0003] In the CMP process, a stopper (a polishing stopper layer including a stopper material) is sometimes used to selectively polish an insulating material. In this case, when the insulating material as the polished material is polished and the stopper is exposed, it is required to stop polishing the stopper. As the stopper material, polysilicon, amorphous silicon, single crystal silicon, and the like are under study. In this case, for the polishing liquid for CMP, it is required to greatly suppress the polishing rate of the stopper material and to have a high polishing rate ratio (polishing selectivity: polishing rate of the insulating material / polishing rate of the stopper material) with respect to the insulating material (for example, refer to Patent Literature 1 below).

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] [Patent Literature 1] Japanese Patent No. 4872919 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] The stopper material is used, for example, as a conductive raw material for a semiconductor device (gate of a transistor, etc.). In this case, if a defect (for example, a recess defect such as a hole) is generated in the stopper based on a chemical action after the CMP process, a large influence is exerted on the reliability of the semiconductor device, and thus it is required to suppress generation of defects in the stopper as much as possible. However, with further densification and miniaturization of semiconductor elements, even a very small amount of defects generated in the stopper can significantly degrade the performance of the semiconductor device. In view of this, it is difficult to suppress generation of defects in the stopper for the related art, and in particular, it is difficult to suppress generation of defects in a stopper containing a silicon material (excluding silicon oxide) such as polysilicon, amorphous silicon, and single-crystal silicon.

[0009] An aspect of the present application is to solve the above-described problem, and aims to provide a polishing liquid and a polishing liquid set capable of suppressing generation of defects in polishing of a polished surface containing a silicon material (excluding silicon oxide) and a polishing method and a defect suppression method using the same.

[0010] Means for solving the technical problem

[0011] In order to solve the above-described problem, the present inventors have intensively studied the components of the polishing liquid. As a result, the present inventors have found that a polishing liquid and a polishing liquid set capable of suppressing generation of defects in polishing of a polished surface containing a silicon material (excluding silicon oxide) can be obtained by using two specific nitrogen-containing compounds.

[0012] An aspect of the present application provides a polishing liquid containing a polishing grain, a first nitrogen-containing compound, a second nitrogen-containing compound, and water, the first nitrogen-containing compound containing at least one selected from the group consisting of (I) a compound having a ring containing one nitrogen atom in the ring and a hydroxyl group, (II) a compound having a ring containing one nitrogen atom in the ring and a functional group containing a nitrogen atom, (III) a compound having a 6-membered ring containing two nitrogen atoms in the ring, (IV) a compound having a benzene ring and a ring containing a nitrogen atom in the ring, and (V) a compound having a benzene ring to which two or more functional groups containing a nitrogen atom are bonded, and the second nitrogen-containing compound having an HLB value of 7 or more.

[0013] With such a polishing liquid, generation of defects in polishing of a polished surface containing a silicon material (excluding silicon oxide) can be suppressed, and in particular, generation of defects based on a chemical action can be suppressed.

[0014] Another aspect of the present application provides a polishing liquid set in which the components of the above-described polishing liquid are stored as a first liquid and a second liquid, the first liquid containing the polishing grain and water, and the second liquid containing the first nitrogen-containing compound, the second nitrogen-containing compound, and water.

[0015] Another aspect of the present application provides a polishing method including a step of polishing a surface to be polished with the polishing liquid described above or a polishing liquid obtained by mixing the first liquid and the second liquid in the polishing liquid set described above.

[0016] Another aspect of the present application provides a defect inhibition method for inhibiting defects in polishing a surface to be polished including a stopper material, the method including a step of polishing a surface to be polished with the polishing liquid described above or a polishing liquid obtained by mixing the first liquid and the second liquid in the polishing liquid set described above.

[0017] Effects of the Invention

[0018] According to one aspect of the present application, a polishing liquid and a polishing liquid set capable of inhibiting defects in polishing a surface to be polished including a silicon material (excluding silicon oxide) can be provided. In addition, according to another aspect of the present application, a polishing method and a defect inhibition method using the polishing liquid or the polishing liquid set can be provided. According to another aspect of the present application, the use of the polishing liquid or the polishing liquid set in a defect inhibition method for inhibiting defects in polishing a surface to be polished including a silicon material (excluding silicon oxide) can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a diagram showing an example of defects.

[0020] Figure 2 is a schematic cross-sectional view showing a polishing method according to an embodiment of the present application. DETAILED DESCRIPTION

[0021] Hereinafter, an embodiment of the present application will be described in detail.

[0022] <DEFINITIONS>

[0023] The term "step" includes not only a single step, but also a step that cannot be clearly distinguished from other steps as long as the desired function of the step can be achieved. A numerical range represented by "~" indicates a range including the values before and after "~" as the minimum and maximum values, respectively. In the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range of a certain stage can be combined arbitrarily with the upper limit value or the lower limit value of the numerical range of another stage. In the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range can be replaced with the value shown in the examples. Unless otherwise specified, the materials exemplified in the present specification can be used alone or in combination of two or more. In the case where a plurality of substances corresponding to each component are present in the composition, unless otherwise specified, the content of each component in the composition indicates the total amount of the plurality of substances present in the composition. "Polishing rate" refers to the speed at which the material is removed per unit time (removal rate = Removal Rate). "A or B" includes either A or B, and can also include both. "A or more" of a numerical range means A and a range exceeding A. "A or less" of a numerical range means A and a range less than A.

[0024] In the present specification, the weight average molecular weight can be measured by reading the value obtained as "Mw" by the following method.

[0025] [Measurement method]

[0026] Machine (detector) used: differential refractometer for liquid chromatograph, manufactured by Hitachi Chemical, Ltd., "L-3300 type".

[0027] Pump: "L-7100" for liquid chromatograph, manufactured by Hitachi Chemical, Ltd.

[0028] Deaeration device: none

[0029] Data processing: GPC integrator "D-2520" manufactured by Hitachi Chemical, Ltd.

[0030] Column: "Shodex Asahipak GF-710HQ", manufactured by Showa Denko K.K., inner diameter 7.6 mm x 300 mm

[0031] Eluent: 50 mM aqueous Na2HPO4 / acetonitrile = 90 / 10 (v / v)

[0032] Measurement temperature: 25°C

[0033] Flow rate: 0.6mL / min (L means liter, the same below)

[0034] Measurement time: 30 minutes

[0035] Sample: A solution with the same composition as the eluent was adjusted to a resin component concentration of 2% by mass and filtered through a 0.45 μm polytetrafluoroethylene filter.

[0036] Injection volume: 0.4 μL

[0037] Standard material: Polymer Laboratories, narrow molecular weight sodium polyacrylate

[0038] Polishing fluid

[0039] The polishing liquid (polishing composition) of this embodiment contains abrasive grains, a first nitrogen-containing compound, a second nitrogen-containing compound, and water. The polishing liquid involved in this embodiment contains at least the first nitrogen-containing compound and the second nitrogen-containing compound as additives in addition to the abrasive grains and water. The polishing liquid of this embodiment can be used as a polishing liquid for CMP.

[0040] According to the polishing liquid of this embodiment, it is possible to suppress the generation of defects, especially the generation of pit defects, during the polishing of the polished surface containing silicon material (material containing silicon, excluding silicon oxide. The same applies hereinafter). Figure 1 As shown, the concave defects are depressions such as holes produced on the ground surface after grinding (for example, Figure 1 The circled portion is generated by chemical reactions. Examples of silicon materials include polysilicon, amorphous silicon, and single crystal silicon.

[0041] However, if the components of the polishing liquid are not fully dispersed and mixed in the polishing liquid, resulting in liquid layer separation, it is difficult to obtain stable properties of the polishing liquid. In contrast, the polishing liquid according to this embodiment can suppress the occurrence of liquid layer separation of the components of the polishing liquid (such as the second nitrogen-containing compound) and can suppress the occurrence of defects during polishing of the polished surface including silicon material.

[0042] The polishing liquid according to this embodiment can be used for polishing using silicon as a stopper material. The polishing liquid according to this embodiment can be used to suppress polishing of at least one selected from the group consisting of polycrystalline silicon, amorphous silicon, and single crystal silicon.

[0043] The polishing target surface can be other polishing target materials (insulating materials, metal materials other than silicon materials, coated organic materials, etc.) in addition to silicon materials. As insulating materials, for example, insulating materials used in interlayer insulating films, BPSG films, STI films, etc. can be mentioned. The polishing liquid of the present embodiment can also be used for polishing insulating materials, for example, can also be used in polishing in which at least a part of an insulating material is removed by CMP to expose a stopper portion containing a silicon material. According to the polishing liquid of the present embodiment, defect generation in a polishing step in which polishing is stopped when an insulating material is polished to expose a stopper portion can be suppressed.

[0044] However, if an insulating material remains on the stopper portion, there is a case in which the reliability of a semiconductor device decreases. In view of this, the polishing liquid of the present embodiment can also be used in a polishing step in which polishing is further performed after the stopper portion is exposed, and can also be used in a polishing step in which the entire portion of the stopper portion covered with an insulating material is exposed by further performing polishing after the stopper portion is exposed. According to the polishing liquid of the present embodiment, even in the case of use in such a polishing step, defect generation can be suppressed.

[0045] (Polishing grains)

[0046] The polishing liquid of the present embodiment contains polishing grains (polishing particles). As a constituent component of the polishing grains, for example, at least one selected from the group consisting of cerium compounds, silicon dioxide (silica), alumina, zirconia, titania, germania, manganese oxide, magnesium oxide, resins, diamond, silicon carbide, cubic boron nitride, and modified products of these can be mentioned. The particles containing the modified products can be particles in which the surface of the particles is modified with an alkyl group; composite particles in which other particles are attached to the surface of the particles; etc. As the particles containing alumina, colloidal alumina can be used. The polishing grains can be used singly, or two or more kinds can be used in combination.

[0047] From the viewpoint of easily obtaining a good polishing rate of an insulating material, the polishing grains preferably contain a cerium compound. As the cerium compound, cerium oxide (cerium dioxide), cerium hydroxide, cerium ammonium nitrate, cerium acetate, cerium sulfate hydrate, cerium bromate, cerium bromide, cerium chloride, cerium oxalate, cerium nitrate, cerium carbonate, etc. can be mentioned. From the viewpoint of stability of the polishing rate of an insulating material, the polishing grains are preferably those containing at least one selected from the group consisting of cerium oxide and cerium hydroxide, and more preferably those containing cerium oxide. As the polishing grains containing a cerium compound, cerium oxide particles (particles containing cerium oxide), cerium hydroxide particles (particles containing cerium hydroxide), etc. can be used. As the cerium oxide particles, colloidal cerium dioxide can also be used.

[0048] In the case of using ceria particles, the larger the crystallite diameter of the ceria particles and the less the crystalline strain, the more the high-speed polishing can be achieved, but there is a tendency that polishing damage to the polished material is easily caused. From the viewpoint, as the preferable ceria particles, particles including two or more crystallites and having a grain boundary, and the like can be exemplified. Further, as other preferable ceria particles, for example, colloidal ceria particles having a crystallite diameter of 5 to 300 nm (for example, colloidal ceria manufactured by Rhodia) can be exemplified.

[0049] In the case where the abrasive particles contain ceria, from the viewpoint of easily obtaining a good polishing rate of an insulating material, the content of ceria in the abrasive particles is preferably 50% by mass or more, more preferably 70% by mass or more, further preferably 90% by mass or more, particularly preferably 95% by mass or more, extremely preferably 97% by mass or more, and very preferably 99% by mass or more, based on the entire abrasive particles (the entire abrasive particles contained in the polishing liquid; the same applies hereinafter). The abrasive particles containing ceria can be in a form substantially formed of ceria (a form in which 100% by mass of the abrasive particles is ceria).

[0050] The abrasive particles can be obtained by any manufacturing method. For example, as a manufacturing method of the oxide, a solid phase method using calcination or the like; a liquid phase method such as a precipitation method, a sol-gel method, a hydrothermal synthesis method, or the like; a gas phase method such as a sputtering method, a laser method, a thermal plasma method, or the like; and the like can be used.

[0051] The ceria particles are preferably obtained by oxidizing cerium salts such as carbonates, nitrates, sulfates, oxalates, and the like. As the method of oxidation, a calcination method of calcining the cerium salts at around 600°C to 900°C, a chemical oxidation method of oxidizing the cerium salts using an oxidizing agent such as hydrogen peroxide, and the like can be exemplified. From the viewpoint of easily obtaining a high polishing rate of an insulating material, as the manufacturing method of the ceria particles, the calcination method is preferable, and from the viewpoint of not easily causing polishing damage on the polished surface after polishing, the chemical oxidation method is preferable.

[0052] In the case where the abrasive particles are agglomerated, the agglomerated abrasive particles can be mechanically pulverized. As the pulverization method, for example, a dry pulverization method using a jet mill or the like, and a wet pulverization method using a planetary bead mill or the like are preferable. The jet mill can apply, for example, the method described in "Chemical Engineering Papers", Vol. 6, No. 5, (1980), pp. 527 to 532.

[0053] The abrasive grains can be dispersed in water as a dispersion medium to obtain a polishing liquid. As a dispersion method, for example, in addition to the usual dispersion treatment using a stirrer, a method using a homogenizer, an ultrasonic disperser, a wet ball mill, or the like can be listed. As to the dispersion method and the particle diameter control method, for example, a method described in "Dispersion Technology Complete Collection" [Information Agency, Incorporated, July 2005] Chapter 3 "Latest Development Trend and Selection Criteria of Various Dispersion Machines" can be used. In addition, the dispersibility of the abrasive grains can be improved by lowering the electric conductivity of the dispersion liquid containing the abrasive grains (for example, 500 mS / m or less). As a method of lowering the electric conductivity of the dispersion liquid, a method in which solid-liquid separation is performed using centrifugal separation or the like to separate the abrasive grains from the dispersion medium, the supernatant (dispersion medium) is discarded, and a dispersion medium having a low electric conductivity is added to perform redispersion, a method using an ultrafiltration, ion exchange resin, or the like, or the like can be listed.

[0054] The abrasive grains dispersed by the method can be further subjected to microparticulation. As a method of microparticulation, for example, a sedimentation fractionation method (a method in which the abrasive grains are subjected to centrifugal separation using a centrifugal separator, are forced to sediment, and only the supernatant is taken out) can be listed. In addition, a high-pressure homogenizer that collides the abrasive grains in the dispersion medium with each other using high pressure can be used.

[0055] From the viewpoint of easily obtaining a good polishing rate of the insulating material, the average particle diameter of the abrasive grains is preferably 10 nm or more, more preferably 20 nm or more, further preferably 50 nm or more, particularly preferably 90 nm or more, extremely preferably more than 90 nm, very preferably 100 nm or more, more further preferably 130 nm or more, further preferably 150 nm or more. From the viewpoint of hardly causing damage to the material to be polished, the average particle diameter of the abrasive grains is preferably 500 nm or less, more preferably 400 nm or less, further preferably 300 nm or less, particularly preferably 200 nm or less. From these viewpoints, the average particle diameter of the abrasive grains is preferably 10 to 500 nm, more preferably 20 to 400 nm, further preferably 50 to 300 nm, particularly preferably 90 to 300 nm, extremely preferably more than 90 nm and 300 nm or less, very preferably 100 to 300 nm, more further preferably 130 to 300 nm, further preferably 150 to 200 nm.

[0056] The average particle diameter of the abrasive grains refers to the value of D50 (average secondary particle diameter, median diameter of the volume distribution, cumulative median value) of the measured sample determined using a laser diffraction type particle size distribution meter (manufactured by HORIBA, Ltd., trade name: LA-920, refractive index: 1.93, light source: He-Ne laser, absorption 0). An appropriate amount (for example, an amount in which the transmittance (H) is 60 to 70% for the measurement of the He-Ne laser) of the measured sample can be used in the measurement of the average particle diameter. In addition, in the case where the polishing liquid containing the abrasive grains is stored by being divided into a slurry in which the abrasive grains are dispersed in water and an additive liquid containing an additive, the slurry can be diluted to an appropriate amount for the measurement.

[0057] The content of the abrasive grains is preferably in the following range based on the total mass of the polishing liquid. From the viewpoint of easily ensuring a sufficient polishing rate of the insulating material, the content of the abrasive grains is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.2% by mass or more, extremely preferably 0.4% by mass or more, and very preferably 0.5% by mass or more. From the viewpoint of easily suppressing the aggregation of the abrasive grains, the content of the abrasive grains is preferably 20% by mass or less, more preferably 10% by mass or less, further preferably 5% by mass or less, particularly preferably 3% by mass or less, and extremely preferably 1% by mass or less. From these viewpoints, the content of the abrasive grains is preferably 0.01 to 20% by mass, more preferably 0.05 to 10% by mass, further preferably 0.1 to 5% by mass, particularly preferably 0.2 to 3% by mass, extremely preferably 0.2 to 1% by mass, very preferably 0.4 to 1% by mass, and more further preferably 0.5 to 1% by mass.

[0058] (Additive)

[0059] [First nitrogen-containing compound]

[0060] The polishing liquid of the present embodiment contains a first nitrogen-containing compound. The first nitrogen-containing compound can function as a defect inhibitor. The first nitrogen-containing compound contains at least one selected from the group consisting of (I) a compound having an aromatic ring having one nitrogen atom in the ring and a hydroxyl group (hereinafter, referred to as "compound (I)"), (II) a compound having an aromatic ring having one nitrogen atom in the ring and a functional group containing a nitrogen atom (except for the compound corresponding to compound (I). Hereinafter, referred to as "compound (II)"), (III) a compound having a 6-membered ring having two nitrogen atoms in the ring (except for the compound corresponding to compound (I) or compound (II). Hereinafter, referred to as "compound (III)"), (IV) a compound having a benzene ring and a ring having a nitrogen atom in the ring (except for the compound corresponding to compound (I), compound (II) or compound (III). Hereinafter, referred to as "compound (IV)"), and (V) a compound having a benzene ring to which two or more functional groups containing a nitrogen atom are bonded (except for the compound corresponding to compound (I), compound (II), compound (III) or compound (IV). Hereinafter, referred to as "compound (V)"). The molecular weight of the first nitrogen-containing compound can be, for example, less than 200. One kind of the first nitrogen-containing compound can be used alone, or two or more kinds thereof can be used in combination.

[0061] From the viewpoint of further inhibiting occurrence of defects, the number of nitrogen atoms in one molecule of the first nitrogen-containing compound is preferably 1 to 4, more preferably 1 to 3. The number of nitrogen atoms can be two or more.

[0062] Compound (I) is a compound having an aromatic ring having one nitrogen atom in the ring and a hydroxyl group. It is presumed that the empty orbital of the nitrogen atom in the ring in compound (I) forms a coordinate bond with the non-shared electron pair of the oxygen atom of the hydroxyl group in the silicon material, and the hydroxyl group of compound (I) forms a hydrogen bond with the hydroxyl group of the silicon material, whereby the surface of the silicon material is favorably protected. In addition, the hydroxyl group of compound (I) does not include OH of a carboxyl group (COOH group). It is presumed that the hydrogen bonding property of OH of a carboxyl group is lower than that of a hydroxyl group.

[0063] As the aromatic ring, a 3-membered ring, a 4-membered ring, a 5-membered ring, a 6-membered ring, etc. can be exemplified, and from the viewpoint of further inhibiting generation of defects, a 6-membered ring is preferable. The aromatic ring is, for example, a heteroaromatic ring. As the aromatic ring having one nitrogen atom in the ring, an azole ring, a pyridine ring, an oxazole ring, a thiazole ring, a thiazine ring, etc. can be exemplified, and from the viewpoint of further inhibiting generation of defects, a pyridine ring is preferable.

[0064] The hydroxyl group of the compound (I) can be a hydroxyl group directly bonded to the aromatic ring, or can be a hydroxyl group not directly bonded to the aromatic ring. From the viewpoint of further suppressing the occurrence of defects, the compound (I) preferably has a hydroxyl group directly bonded to the aromatic ring. From the viewpoint of further suppressing the occurrence of defects, the number of hydroxyl groups is preferably 1 to 3, more preferably 1 to 2, and further preferably 1. From the viewpoint of further suppressing the occurrence of defects, the hydroxyl group is preferably bonded to a carbon atom adjacent to the nitrogen atom contained in the aromatic ring.

[0065] From the viewpoint of further suppressing the occurrence of defects, as the compound (I), a hydroxypyridine is preferable. As the hydroxypyridine, 2-hydroxypyridine, 3-hydroxypyridine, 4-hydroxypyridine, and the like can be given.

[0066] The compound (II) is a compound having an aromatic ring having one nitrogen atom in the ring, and a functional group containing a nitrogen atom. It is presumed that the empty orbital of the nitrogen atom in the ring in the compound (II) is coordinatedly bonded to the non-shared electron pair of the oxygen atom of the hydroxyl group in the silicon material, and the hydroxyl group of the compound (II) is hydrogen-bonded to the hydroxyl group of the silicon material, whereby the surface of the silicon material is favorably protected.

[0067] As the aromatic ring, a 3-membered ring, a 4-membered ring, a 5-membered ring, a 6-membered ring, and the like can be given, and from the viewpoint of further suppressing the occurrence of defects, a 6-membered ring is preferable. The aromatic ring is, for example, a heteroaromatic ring. As the aromatic ring having one nitrogen atom in the ring, an oxazole ring, a pyridine ring, an oxazole ring, a thiazole ring, a thiazine ring, and the like can be given, and from the viewpoint of further suppressing the occurrence of defects, a pyridine ring is preferable.

[0068] As the functional group containing a nitrogen atom, an amino group, an amide group, a sulfonamide group, and the like can be given, and from the viewpoint of further suppressing the occurrence of defects, at least one selected from the group consisting of an amino group and an amide group is preferable. The functional group containing a nitrogen atom can be a functional group directly bonded to the aromatic ring, or can be a functional group not directly bonded to the aromatic ring. From the viewpoint of further suppressing the occurrence of defects, the compound (II) preferably has a functional group directly bonded to the aromatic ring as the functional group containing a nitrogen atom. From the viewpoint of further suppressing the occurrence of defects, the number of hydroxyl groups is preferably 1 to 3, more preferably 1 to 2, and further preferably 1. From the viewpoint of further suppressing the occurrence of defects, the functional group containing a nitrogen atom is preferably bonded to a carbon atom at the 2-position or the 3-position with respect to the nitrogen atom at the 1 -position contained in the aromatic ring.

[0069] From the viewpoint of further suppressing the occurrence of defects, as the compound (II), at least one selected from the group consisting of an aminopyridine, a methylpyridine amide, and a nicotinamide is preferable. As the aminopyridine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, and the like can be given.

[0070] Compound (III) is a compound having a 6-membered ring containing 2 nitrogen atoms in the ring. It is speculated that the empty orbital of the nitrogen atom in the ring of compound (III) and the non-shared electron pair of the oxygen atom of the hydroxyl group in the silicon material are coordinately bonded at two locations, thereby suitably protecting the surface of the silicon material. It is speculated that in compounds having 5-membered rings (pyrazole, etc.), nitrogen atoms with empty orbitals and nitrogen atoms with non-shared electron pairs are mixed and close to each other, so the coordination bonding and hydrogen bonding properties are weak. It is speculated that even in the case of nitrogen atoms containing 3 or more 6-membered rings in the ring, nitrogen atoms with empty orbitals and nitrogen atoms with non-shared electron pairs are mixed and close to each other, so the coordination bonding and hydrogen bonding properties are weak.

[0071] Examples of the 6-membered ring include aromatic rings and non-aromatic rings. From the perspective of further suppressing the generation of defects, aromatic rings are preferred. Examples of aromatic rings include heteroaromatic rings. As the 6-membered ring containing two nitrogen atoms, a pyrazine ring is preferred.

[0072] From the viewpoint of further suppressing the generation of defects, in compound (III), the number of functional groups containing nitrogen atoms is preferably 1 or less. Examples of functional groups containing nitrogen atoms include amino, amide, and sulfonamide. The functional groups containing nitrogen atoms do not include a 6-membered ring containing two nitrogen atoms within the ring.

[0073] Examples of compound (III) include pyrazine, pyrazinamide, 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, 2,3-diethylpyrazine, and 2,3,5,6-tetramethylpyrazine. From the perspective of further suppressing the generation of defects, at least one compound (III) is preferably selected from the group consisting of pyrazine, pyrazinamide, 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, and 2,3,5,6-tetramethylpyrazine.

[0074] Compound (IV) is a compound having a benzene ring and a ring containing a nitrogen atom. It is speculated that the electron-withdrawing property of the benzene ring in compound (IV) enhances the coordination bonding between the vacant orbital of the nitrogen atom in the ring of compound (IV) and the unshared electron pair of the oxygen atom of the hydroxyl group in the silicon material, thereby appropriately protecting the surface of the silicon material.

[0075] Examples of the ring containing a nitrogen atom include a 3-membered ring, a 4-membered ring, a 5-membered ring, and a 6-membered ring. From the perspective of further suppressing the generation of defects, a 5-membered ring is preferred. The ring containing a nitrogen atom in the ring may be an aromatic ring or a non-aromatic ring. Examples of the ring containing a nitrogen atom in the ring include a pyridine ring, an azole ring, a triazole ring, an imidazole ring, a pyrazole ring, an oxazole ring, a thiazole ring, a pyrazine ring, a thiazine ring, an aza From the viewpoint of further suppressing the occurrence of defects, the number of nitrogen atoms in the ring is preferably 2 or more. From the viewpoint of further suppressing the occurrence of defects, the number of nitrogen atoms in the ring is preferably 4 or less, more preferably 3 or less. The benzene ring and the ring containing a nitrogen atom in the ring can or can not share carbon atoms constituting the ring.

[0076] From the viewpoint of further suppressing the occurrence of defects, as the compound (IV), at least one selected from the group consisting of benzotriazole and 1-phenyl-3-pyridazinone is preferable.

[0077] The compound (V) is a compound having a benzene ring to which 2 or more functional groups containing a nitrogen atom are bonded. It is presumed that the functional group containing a nitrogen atom of the compound (V) forms a hydrogen bond with a hydroxyl group of a silicon material, and that the hydrogen bond is enhanced due to the electron-withdrawing property of the benzene ring in the compound (V), whereby the surface of the silicon material is suitably protected. It is presumed that in the case where the functional group containing a nitrogen atom is 1, the hydrogen bond is not sufficiently enhanced by the electron-withdrawing property of the benzene ring.

[0078] Two or more functional groups containing a nitrogen atom are directly bonded to the benzene ring as substituents. From the viewpoint of suppressing the occurrence of defects, as the functional group containing a nitrogen atom, at least one selected from the group consisting of an amino group, an amide group, and a sulfonamide group is preferable. From the viewpoint of further suppressing the occurrence of defects, the number of functional groups containing a nitrogen atom is preferably 2 to 4, more preferably 2 to 3, further preferably 2. From the viewpoint of further suppressing the occurrence of defects, with respect to the arrangement of the functional groups containing a nitrogen atom, it is preferable that one functional group is located at the para position of the benzene ring with respect to the other functional group.

[0079] From the viewpoint of further suppressing the occurrence of defects, as the compound (V), at least one selected from the group consisting of sulfanilamide and p-aminobenzamide is preferable. The compound (V) can include a compound having no sulfonamide group. The compound (V) can not include a compound having a sulfonamide group.

[0080] From the viewpoint of further suppressing the generation of defects, the first nitrogen-containing compound preferably comprises at least one compound selected from the group consisting of Compound (II), Compound (III), and Compound (IV), more preferably comprises at least one compound selected from the group consisting of Compound (II) and Compound (III), and even more preferably comprises at least one compound selected from the group consisting of nicotinamide, aminopyridine, and pyrazinamide. From the viewpoint of further suppressing the generation of defects, the first nitrogen-containing compound preferably comprises Compound (II), Compound (III), or Compound (IV), more preferably comprises Compound (II) or Compound (III), and even more preferably comprises nicotinamide, aminopyridine, or pyrazinamide.

[0081] Based on the total mass of the polishing liquid, the content of the first nitrogen-containing compound is preferably in the following range. From the perspective of easily obtaining a sufficient defect suppression effect, the content of the first nitrogen-containing compound is preferably 0.001% by mass or more, more preferably 0.005% by mass or more, further preferably 0.01% by mass or more, particularly preferably 0.03% by mass or more, extremely preferably 0.05% by mass or more, very preferably 0.07% by mass or more, and further preferably 0.1% by mass or more. From the perspective of easily ensuring a sufficient polishing speed for the insulating material, the content of the first nitrogen-containing compound is preferably 10% by mass or less, more preferably 5% by mass or less, further preferably 3% by mass or less, particularly preferably 1% by mass or less, extremely preferably 0.5% by mass or less, very preferably 0.3% by mass or less, further preferably 0.2% by mass or less, and further preferably 0.1% by mass or less. From these viewpoints, the content of the first nitrogen-containing compound is preferably 0.001% by mass to 10% by mass.

[0082] [Second nitrogen-containing compound]

[0083] The polishing liquid involved in this embodiment contains a second nitrogen-containing compound (excluding the compound corresponding to the first nitrogen-containing compound). From the perspective of fully obtaining the defect suppression effect, the HLB value of the second nitrogen-containing compound is greater than 7. The second nitrogen-containing compound can act as a defect inhibitor that suppresses defects that cannot be completely suppressed by the first nitrogen-containing compound alone. In addition, in addition to the effect of suppressing defects, the second nitrogen-containing compound can also have the effect of suppressing the polishing speed of the stop portion material. The second nitrogen-containing compound can include a nitrogen-containing polymer compound. The molecular weight (for example, weight average molecular weight) of the second nitrogen-containing compound can be, for example, greater than 200.

[0084] According to the polishing liquid related to the present embodiment, by using the first nitrogen-containing compound and the second nitrogen-containing compound, it is possible to suppress the generation of defects in polishing of a surface to be polished including a silicon material, and in particular, it is possible to suppress the generation of defects based on chemical action. The detailed reason why this effect is exerted is not necessarily clear, but the present inventors and others conjecture the following as one example of the reason. That is, there are hydroxyl groups on the surface of a silicon material such as polysilicon, amorphous silicon, and single-crystal silicon. In this case, by using a compound that can form a hydrogen bond or a coordination bond with at least two or more hydroxyl groups of the silicon material, or a compound that can enhance the hydrogen bond or the coordination bond with the hydroxyl groups of the silicon material as the first nitrogen-containing compound, the surface of the silicon material is suitably protected. It is conjectured that, in addition, in the presence of the second nitrogen-containing compound that is easily dispersed and mixed in the polishing liquid and that easily obtains stable properties, the effect as described above is sufficiently exerted by using the first nitrogen-containing compound, and thus it is possible to suppress the generation of defects.

[0085] From the viewpoint of easily dispersing and mixing the second nitrogen-containing compound in the polishing liquid and easily obtaining stable properties, the HLB value of the second nitrogen-containing compound is preferably 8 or greater, more preferably 8.5 or greater, further preferably 9 or greater, particularly preferably 9.5 or greater, and extremely preferably 10 or greater. The HLB value of the second nitrogen-containing compound can be 11 or greater, 11.5 or greater, 12 or greater, 12.5 or greater, or 13 or greater. The HLB value of the second nitrogen-containing compound can be 20 or less, 19 or less, 18 or less, 17 or less, 16 or less, 15 or less, 14.5 or less, 14 or less, or 13.5 or less. The HLB value of the second nitrogen-containing compound can be 7 to 20.

[0086] From the viewpoint of easily obtaining a defect suppression effect sufficiently, the second nitrogen-containing compound preferably has a hydrocarbon group bonded to a nitrogen atom. As the hydrocarbon group, a saturated hydrocarbon group (alkyl group) and an unsaturated hydrocarbon group, and the like can be given. From the viewpoint of easily obtaining a defect suppression effect sufficiently, the number of carbon atoms of the hydrocarbon group is preferably 3 or greater, more preferably 6 or greater, further preferably 9 or greater, particularly preferably 10 or greater, and extremely preferably 12 or greater. From the viewpoint of easily suppressing the aggregation of abrasive grains, the number of carbon atoms of the hydrocarbon group is preferably 30 or less, more preferably 24 or less, further preferably 21 or less, and particularly preferably 18 or less. From these viewpoints, the number of carbon atoms of the hydrocarbon group is preferably 3 to 30. The number of carbon atoms of the hydrocarbon group can be 15 or greater or 18 or greater.

[0087] From the viewpoint of being able to sufficiently obtain a defect inhibiting effect, the second nitrogen-containing compound preferably contains an amine, more preferably a polyether amine. From the viewpoint of being able to easily sufficiently obtain a defect inhibiting effect, the amine preferably has a polyoxyalkylene group. From the viewpoint of being able to easily sufficiently obtain a defect inhibiting effect, as the polyoxyalkylene group, a polyoxyethylene group is preferable. From the viewpoint of being able to easily sufficiently obtain a defect inhibiting effect, the second nitrogen-containing compound preferably contains a compound having one or two polyoxyalkylene groups bonded to a nitrogen atom (the same nitrogen atom), more preferably a compound having one or two polyoxyethylene groups bonded to a nitrogen atom (the same nitrogen atom).

[0088] As the polyether amine, polyoxyethylene alkyl amine (polyoxyethylene oleyl amine, polyoxyethylene lauryl amine, polyoxyethylene stearyl amine, polyoxyethylene tallow alkyl amine, polyoxyethylene alkyl (coconut) amine, etc.), polyoxyethylene polyoxypropylene lauryl amine, polyoxyethylene alkyl propylene diamine, etc. can be exemplified. From the viewpoint of being able to easily sufficiently obtain a defect inhibiting effect, the second nitrogen-containing compound preferably contains at least one selected from the group consisting of polyoxyethylene alkyl amine and polyoxyethylene alkyl propylene diamine, more preferably at least one selected from the group consisting of polyoxyethylene oleyl amine, polyoxyethylene lauryl amine, polyoxyethylene stearyl amine, polyoxyethylene tallow alkyl amine, and polyoxyethylene alkyl propylene diamine.

[0089] The second nitrogen-containing compound can also contain an alkanolamide compound (a compound having a hydroxyl group and an amide group in an alkane skeleton). The alkanolamide compound can contain an alkanolamide / alkylene oxide adduct (for example, an alkanolamide ethylene oxide adduct), and can contain an alkanolamide / alkylene oxide adduct having a polyoxyalkylene group (for example, a polyoxyethylene group) bonded to a nitrogen atom constituting an amide group.

[0090] From the viewpoint of being able to easily sufficiently obtain a defect inhibiting effect, the second nitrogen-containing compound preferably contains a compound represented by the following (X). From the viewpoint of being able to easily sufficiently obtain a defect inhibiting effect, the second nitrogen-containing compound is more preferably a compound containing one or two of R 1 , R 2 , and R 3 in General Formula (X) as a polyoxyalkylene group, and is still more preferably a compound containing one or two of R 1 , R 2 , and R 3 in General Formula (X) as a polyoxyethylene group.

[0091]

[0092] [In the formula, R 1 , R 2 , and R 3 independently represent a polyoxyalkylene group or a hydrocarbon group which can have a substituent.]

[0093] As the polyoxyalkylene group, a polyoxyethylene group, a polyoxypropylene group, and the like can be given. From the viewpoint of easily obtaining a defect inhibiting effect sufficiently, as the polyoxyalkylene group, a polyoxyethylene group is preferable.

[0094] As the hydrocarbon group, a saturated hydrocarbon group (alkyl group), an unsaturated hydrocarbon group, and the like can be given. From the viewpoint of easily obtaining a defect inhibiting effect sufficiently, as the hydrocarbon group, the number of carbon atoms of the hydrocarbon group bonded to the nitrogen atom is preferably the number of carbon atoms described above. As the substituent of the hydrocarbon group, a hydroxyl group, a carboxyl group, an amino group, a substituted amino group, and the like can be given. The substituted amino group can be a secondary amino group or a tertiary amino group. As the substituent of the substituted amino group, a hydrocarbon group (for example, an alkyl group), a polyoxyalkylene group (for example, a polyoxyethylene group), and the like can be given. As the substituted amino group, a group in which one hydrocarbon group (for example, an alkyl group) and one polyoxyalkylene group (for example, a polyoxyethylene group) are bonded to the nitrogen atom constituting the amino group, a group in which two polyoxyalkylene groups (for example, polyoxyethylene groups) are bonded to the nitrogen atom constituting the amino group, and the like can be given.

[0095] From the viewpoint of easily obtaining a defect inhibiting effect sufficiently, the content of the second nitrogen-containing compound is preferably 0.0001% by mass or more, more preferably 0.0003% by mass or more, further preferably 0.0005% by mass or more, particularly preferably 0.0008% by mass or more, extremely preferably 0.001% by mass or more, very preferably 0.002% by mass or more, more further preferably 0.003% by mass or more, further preferably 0.004% by mass or more, particularly preferably 0.005% by mass or more, extremely preferably 0.008% by mass or more, and very preferably 0.01% by mass or more. From the viewpoint of easily inhibiting the aggregation of abrasive grains, the content of the second nitrogen-containing compound is preferably 1.0% by mass or less, more preferably 0.5% by mass or less, further preferably 0.1% by mass or less, particularly preferably 0.05% by mass or less, extremely preferably 0.03% by mass or less, and very preferably 0.01% by mass or less. From these viewpoints, the content of the second nitrogen-containing compound is preferably 0.0001 to 1.0% by mass. The content of the second nitrogen-containing compound can be less than 0.01% by mass, 0.008% by mass or less, 0.005% by mass or less, less than 0.005% by mass, 0.003% by mass or less, or 0.001% by mass or less.

[0096] [High Molecular Compound (A)]

[0097] The polishing liquid according to the present embodiment can contain a high molecular compound (A) having at least one selected from the group consisting of a carboxyl group and a carboxylate group (except for the first nitrogen-containing compound or the second nitrogen-containing compound). By using the high molecular compound (A), dishing can be inhibited.

[0098] The high molecular compound (A) can be used singly or in combination of two or more. The high molecular compound (A) preferably contains a polymer or a salt thereof obtained by polymerizing a monomer containing at least one selected from the group consisting of acrylic acid and methacrylic acid (hereinafter, these are collectively referred to as "(meth)acrylic acid-based polymer"). The monomer can contain acrylic acid or other monomers copolymerizable with methacrylic acid (except for acrylic acid and methacrylic acid).

[0099] As the high molecular compound (A), at least one selected from the group consisting of a homopolymer of acrylic acid (polyacrylic acid), a homopolymer of methacrylic acid (polymethacrylic acid), a copolymer of acrylic acid and methacrylic acid, a copolymer of acrylic acid or methacrylic acid and other monomer, a copolymer of acrylic acid and methacrylic acid and other monomer, and a salt of these can also be used. Among them, as the (meth)acrylic acid-based polymer, at least one selected from the group consisting of a homopolymer of acrylic acid (polyacrylic acid) and a salt thereof is preferable from the viewpoint of good adsorption to the stopper material. As the salt of the polymer (polymer having a carboxylate group), an ammonium salt or the like can be exemplified. As the ammonium salt, polyammonium acrylate or the like can be exemplified. The (meth)acrylic acid-based polymer can be used singly or in combination of two or more.

[0100] As the other monomer (monomer copolymerizable with acrylic acid or methacrylic acid), for example, unsaturated carboxylic acids such as butenoic acid, pentenoic acid, hexenoic acid, heptenoic acid, octenoic acid, nonenoic acid, decenoic acid, undecenoic acid, dodecenoic acid, tridecenoic acid, tetradecenoic acid, pentadecenoic acid, hexadecenoic acid, and heptadecenoic acid; and vinyl compounds such as ethylene, propylene, and styrene can be exemplified.

[0101] The weight average molecular weight of the high molecular compound (A) is preferably in the following range. From the viewpoint of easily obtaining a good polishing rate when polishing an insulating material (silicon oxide or the like), the weight average molecular weight of the high molecular compound (A) is preferably 100 or more, more preferably 1000 or more, further preferably 2000 or more, and particularly preferably 2500 or more. From the viewpoint of the tendency that the storage stability of the polishing liquid is difficult to be lowered, the weight average molecular weight of the high molecular compound (A) is preferably 150,000 or less, more preferably 80,000 or less, further preferably 10,000 or less, particularly preferably 7,000 or less, and most preferably 5,000 or less. From these viewpoints, the weight average molecular weight of the high molecular compound (A) is preferably 100 to 150,000, more preferably 1000 to 80,000, further preferably 1000 to 10,000, particularly preferably 2000 to 7000, and most preferably 2500 to 5000.

[0102] The content of the high-molecular compound (A) is preferably in the following range based on the total mass of the polishing liquid. From the viewpoint of easily reducing the amount of recesses and the like and easily sufficiently ensuring surface flatness, the content of the high-molecular compound (A) is preferably 0.001 mass% or more, more preferably 0.01 mass% or more, and further preferably 0.1 mass% or more. From the viewpoint of easily suppressing a decrease in the storage stability of the abrasive grains and easily producing aggregation of the abrasive grains and the like, the content of the high-molecular compound (A) is preferably 2 mass% or less, more preferably 1 mass% or less, further preferably 0.5 mass% or less, and particularly preferably 0.3 mass% or less. From these viewpoints, the content of the high-molecular compound (A) is preferably 0.001 mass% to 2 mass%, more preferably 0.01 mass% to 1 mass%, further preferably 0.1 mass% to 0.5 mass%, and particularly preferably 0.1 mass% to 0.3 mass%.

[0103] [High-molecular compound (B): nonionic high-molecular compound]

[0104] The polishing liquid according to the present embodiment can contain a nonionic high-molecular compound (B) (except for the first nitrogen-containing compound, the second nitrogen-containing compound, or the high-molecular compound (A)). The high-molecular compound (B) can function as a stop material polishing inhibitor that inhibits polishing of the stop material. By using the high-molecular compound (B), an excellent polishing rate ratio of the insulating material to the stop material can be obtained.

[0105] As the high-molecular compound (B), polyalkylene glycol, polyalkylene oxide derivative, polyglycerol, vinyl alcohol polymer, copolymer having a structural unit derived from polyvinylpyrrolidone and vinylpyrrolidone, other water-soluble nonionic compound, and the like can be given. The high-molecular compound (B) can be used alone or in combination of two or more.

[0106] As the polyalkylene glycol, polyethylene glycol, polypropylene glycol, and the like can be given.

[0107] As the polyalkylene oxide derivative, a compound in which a functional group and / or a substituent is introduced into polyalkylene glycol, a compound in which polyalkylene oxide is added to an organic compound, and the like can be given.

[0108] As the functional group and the substituent, alkyl ether, alkylphenyl ether, phenyl ether, styrenated phenyl ether, fatty acid ester, glycol ester, polyglycerol ether, diglycerol ether, sugar ether, sugar ester, and the like can be given.

[0109] As polyoxyalkylene derivatives, there can be mentioned: polyoxyethylene styrenated phenyl ethers (e.g., manufactured by NOF Corporation, NOIGEN (registered trademark) EA series); polyoxyethylene alkyl ethers (e.g., manufactured by Kao Corporation, EMULGEN (registered trademark) series); polyoxyethylene alkyl phenyl ethers (e.g., manufactured by NOF Corporation, EMULJIT (registered trademark) series); polyoxyethylene sorbitan fatty acid esters (e.g., manufactured by NOF Corporation, SORGEN (registered trademark) TW series); polyoxyethylene fatty acid esters (e.g., manufactured by Kao Corporation, EMANON (registered trademark) series); polyoxypropylene sorbitol (e.g., manufactured by Nisshin Oil Mills, Ltd., UNIOL (registered trademark) HS-1600D); polyoxyethylene diglycerol ethers such as polyoxyethylene diglycerol ethers (e.g., manufactured by SAKAMOTO YAKUHIN KOGYO CO., LTD., SC-E series), polyoxypropylene diglycerol ethers (e.g., manufactured by SAKAMOTO YAKUHIN KOGYO CO., LTD., SY-DP series); polyoxyethylene polyglyceryl ethers, polyoxypropylene polyglyceryl ethers, polyoxyethylene polyoxypropylene glycol ethers (e.g., manufactured by NOF Corporation, EPAN); and the like. Compounds to which polyalkylene oxide is added (e.g., manufactured by Air Products Japan, SURFYNOL (registered trademark) 465; manufactured by Nikko Emulsion Co., Ltd., TMP series); and the like.

[0110] There is a tendency that the vinyl alcohol, if it is a monomer, does not exist as a stable compound, and thus a vinyl alcohol polymer can be obtained by polymerizing a vinyl acetate monomer or the like carboxylic acid vinyl ester monomer to obtain a poly carboxylic acid vinyl ester, and then saponifying (hydrolyzing) it. Thus, for example, a vinyl alcohol polymer obtained using a vinyl acetate monomer as a raw material has -OCOCH3, and -OH hydrolyzed out as functional groups in the molecule, and the proportion of -OH is defined as the saponification degree. That is, a vinyl alcohol polymer having a saponification degree of less than 100% substantially has a structure like a copolymer of vinyl acetate and vinyl alcohol. In addition, the vinyl alcohol polymer can also be a polymer obtained by copolymerizing a vinyl acetate monomer or the like carboxylic acid vinyl ester monomer with another monomer containing a vinyl group (e.g., ethylene, propylene, styrene, vinyl chloride), and then saponifying all or a part of the portion derived from the carboxylic acid vinyl ester monomer. As such a vinyl alcohol polymer, specifically, there can be mentioned PVA-403 manufactured by KURARAY CO., LTD., JC-25 manufactured by JAPAN VAM & POVAL CO., LTD., and the like. In this specification, these are collectively defined as "vinyl alcohol polymers".

[0111] The vinyl alcohol polymer can also be a derivative of a homopolymer of vinyl alcohol (i.e., a polymer having a saponification degree of 100%), a derivative of a copolymer of vinyl alcohol monomer and other monomers containing a vinyl group (e.g., ethylene, propylene, styrene, vinyl chloride, vinyl acetate), and the like. As such derivatives, there can be mentioned compounds in which at least a part of the hydroxyl groups are substituted with amine groups, carboxyl groups, ester groups, and the like, compounds in which at least a part of the hydroxyl groups are modified, and the like, and specifically, there can be mentioned reactive polyvinyl alcohol (e.g., manufactured by Nippon Shokubai Co., Ltd., GOHSEFIMER (registered trademark) Z), cationized polyvinyl alcohol (e.g., manufactured by Nippon Shokubai Co., Ltd., GOHSEFIMER (registered trademark) K), anionized polyvinyl alcohol (e.g., manufactured by Nippon Shokubai Co., Ltd., GOHSELAN (registered trademark) L, GOSENOL (registered trademark) T), hydrophilic group-modified polyvinyl alcohol (e.g., manufactured by Nippon Shokubai Co., Ltd., ECOMATY (registered trademark)), and the like.

[0112] As other water-soluble nonionic compounds, there can be mentioned polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol distearate, polyethylene glycol monooleate, polyoxyethylene hardened castor oil, and the like.

[0113] The weight average molecular weight of the high molecular compound (B) is preferably in the following range. From the viewpoint of easily obtaining good planarity when polishing an insulating material (silicon oxide or the like), the weight average molecular weight of the high molecular compound (B) is preferably 100 or greater, more preferably 300 or greater, and further preferably 500 or greater. From the viewpoint of easily obtaining a good polishing rate when polishing an insulating material (silicon oxide or the like), the weight average molecular weight of the high molecular compound (B) is preferably 10,000 or less, more preferably 7,000 or less, and further preferably 5,000 or less. From these viewpoints, the weight average molecular weight of the high molecular compound (B) is preferably 100 to 10,000, more preferably 300 to 7,000, and further preferably 500 to 5,000.

[0114] The content of the high-molecular compound (B) is preferably in the following range based on the total mass of the polishing liquid. From the viewpoint of easily ensuring the effect of suppressing polishing of the stopper material, the content of the high-molecular compound (B) is preferably 0.005 mass% or more, more preferably 0.01 mass% or more, further preferably 0.015 mass% or more, particularly preferably 0.02 mass% or more, extremely preferably 0.03 mass% or more, and very preferably 0.04 mass% or more. From the viewpoint of easily ensuring a sufficient polishing rate of the insulating material, the content of the high-molecular compound (B) is preferably 2 mass% or less, more preferably 1.5 mass% or less, further preferably 1 mass% or less, particularly preferably 0.5 mass% or less, extremely preferably 0.1 mass% or less, and very preferably 0.05 mass% or less. From these viewpoints, the content of the high-molecular compound (B) is preferably 0.005 mass% to 2 mass%, more preferably 0.01 mass% to 1.5 mass%, further preferably 0.015 mass% to 1 mass%, particularly preferably 0.02 mass% to 0.5 mass%, extremely preferably 0.03 mass% to 0.1 mass%, and very preferably 0.04 mass% to 0.05 mass%.

[0115] [pH adjuster]

[0116] The polishing liquid according to the present embodiment can contain a pH adjuster (except for the first nitrogen-containing compound, the second nitrogen-containing compound, the high-molecular compound (A), or the high-molecular compound (B)). By the pH adjuster, the pH can be adjusted to a desired value. There is no particular limitation on the pH adjuster, and examples thereof include basic compounds such as ammonia, sodium hydroxide, potassium hydroxide, calcium hydroxide, and the like; acid components such as organic acid components, inorganic acid components, and the like. Examples of the inorganic acid component include nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, boric acid, and the like. The pH adjuster can be used singly or in combination of two or more. In the case where the polishing liquid is used for polishing of a semiconductor, ammonia or an acid component is preferably used.

[0117] From the viewpoint of easily obtaining a good polishing rate of the insulating material, as the pH adjuster, a basic compound is preferable, and ammonia is more preferable. Since the basic compound can be a cause of recess defects, it is preferable that the content of the basic compound be as small as possible. From the viewpoint of further suppressing generation of defects, the content of the basic compound is preferably 0.04 mol / kg or less, more preferably 0.035 mol / kg or less, and further preferably 0.03 mol / kg or less, based on the total amount of the polishing liquid. The content of the basic compound can be 0.01 mol / kg or more or 0.015 mol / kg or more, based on the total amount of the polishing liquid.

[0118] [other additives]

[0119] The polishing liquid according to the present embodiment can contain an additive other than the first nitrogen-containing compound, the second nitrogen-containing compound, the high-molecular compound (A), the high-molecular compound (B), and the pH adjustor. As such an additive, a water-soluble high-molecular compound or the like can be exemplified. In the case where the polishing liquid is stored by being divided into a slurry and an additive liquid, it is preferable that these other additives be contained in the additive liquid. As the water-soluble high-molecular compound, polysaccharides such as alginic acid, pectic acid, carboxymethyl cellulose, agar, curdlan, and pullulan, or the like can be exemplified. These additives can be used singly or in combination of two or more. The content of these additives is preferably 0.01 to 5 mass% based on the total mass of the polishing liquid.

[0120] The content of the oxidizing agent (e.g., hydrogen peroxide) in the polishing liquid of the present embodiment can be less than 0.1 mass%, less than 0.07 mass%, less than 0.05 mass%, or less than 0.01 mass%. The polishing liquid of the present embodiment can also not contain an oxidizing agent (e.g., hydrogen peroxide). The polishing liquid of the present embodiment can also not contain an aromatic carboxylic acid. The content of the sulfonic acid in the polishing liquid of the present embodiment can be less than 0.01 mass%. The polishing liquid of the present embodiment can also not contain a sulfonic acid. The polishing liquid of the present embodiment can also not contain a diazine compound.

[0121] (Water)

[0122] The water is not particularly limited, but deionized water, ion-exchanged water, ultrapure water, or the like is preferable. The content of the water can be the remaining portion of the content of each of the components described above, and is not particularly limited as long as it is contained in the polishing liquid. In addition, the polishing liquid can further contain a solvent other than water, such as a polar solvent such as ethanol or acetone, as necessary.

[0123] (pH)

[0124] From the viewpoint of easily obtaining an excellent polishing rate of an insulating material, and the viewpoint of easily obtaining sufficient storage stability of the abrasive grains and easily suppressing generation of agglomeration of the abrasive grains and the like, the pH of the polishing liquid according to the present embodiment is preferably 3.0 or greater, more preferably 3.5 or greater, further preferably greater than 3.5, particularly preferably 4.0 or greater, extremely preferably greater than 4.0, very preferably 4.5 or greater, further more preferably 5.0 or greater, more preferably 5.5 or greater, particularly preferably 6.0 or greater, extremely preferably greater than 6.0. From the viewpoint of easily suppressing generation of defects (recess defects and the like), and the viewpoint of easily ensuring surface flatness after polishing (easily suppressing recesses and the like), the pH of the polishing liquid according to the present embodiment is preferably 8.0 or less, more preferably less than 8.0, further preferably 7.5 or less, particularly preferably 7.0 or less, extremely preferably 6.5 or less. From these viewpoints, the pH of the polishing liquid according to the present embodiment is preferably 3.0 to 8.0, more preferably 3.5 or greater and less than 8.0, further preferably greater than 3.5 and 7.5 or less, particularly preferably 4.0 to 7.5, extremely preferably greater than 4.0 and 7.5 or less, very preferably 4.5 to 7.0, further more preferably 5.0 to 6.5, further preferably 5.5 to 6.5, particularly preferably 6.0 to 6.5, extremely preferably greater than 6.0 and 6.5 or less. The pH of the polishing liquid is the pH of the polishing liquid at 25°C.

[0125] The pH of the polishing liquid can be measured using a pH meter (for example, manufactured by Yokogawa Electric Corporation, trade name: Model PH81). For example, after 2-point calibration using standard buffers (phthalate pH buffer, pH: 4.01 (25°C), and neutral phosphate pH buffer, pH: 6.86 (25°C)), the electrode is immersed in the polishing liquid, and the value after 2 minutes or more at 25°C is measured as the pH.

[0126] <Method for producing polishing liquid>

[0127] The method for producing the polishing liquid according to the present embodiment includes at least a polishing liquid production step of mixing a first nitrogen-containing compound, a second nitrogen-containing compound, and water to obtain a polishing liquid. In the polishing liquid production step, the components can be mixed simultaneously, or the components can be mixed sequentially. The method for producing the polishing liquid according to the present embodiment can also include, before the polishing liquid production step, a step of obtaining abrasive grains (for example, abrasive grains containing cerium), and a step of obtaining an additive (for example, the high molecular compound (A) and / or the high molecular compound (B)).

[0128] The manufacturing method of the polishing liquid of the present embodiment can also include a dispersion step of dispersing the abrasive grains in water. The dispersion step is, for example, a step of mixing the abrasive grains, the dispersant, and water and dispersing the abrasive grains in water to obtain the slurry.

[0129] <Polishing liquid kit>

[0130] The polishing liquid of the present embodiment can be stored as a multi-liquid (e.g., two-liquid) polishing liquid kit (e.g., CMP polishing liquid kit) by separating the components of the polishing liquid into a slurry (first liquid) and an additive liquid (second liquid). The slurry contains, for example, at least the abrasive grains and water. The additive liquid contains, for example, at least the additive (e.g., the first nitrogen-containing compound and the second nitrogen-containing compound) and water. The pH adjuster can also be contained in the slurry as long as it does not change the polarity of the potential of the abrasive grains contained in the slurry. The components of the polishing liquid can be stored as two liquids, the slurry and the additive liquid, or as three or more liquids.

[0131] In the polishing liquid kit, the slurry and the additive liquid are mixed immediately before polishing or during polishing to prepare the polishing liquid. The multi-liquid polishing liquid kit can also be stored in the form of a slurry storage liquid and an additive liquid storage liquid with reduced water content, and used after dilution with water immediately before polishing or during polishing.

[0132] <Polishing method>

[0133] In the polishing method of the present embodiment, a polishing step of polishing a polished surface using the polishing liquid of the present embodiment or a polishing liquid obtained by mixing the slurry and the additive liquid in the polishing liquid kit of the present embodiment. The polished surface can contain, for example, a silicon material. The polished surface can contain at least one selected from the group consisting of polysilicon, amorphous silicon, and single crystal silicon, and can contain amorphous silicon.

[0134] The polishing method of the present embodiment is, for example, a polishing method of a substrate having a polished surface containing a silicon material. The polishing step can be a step of selectively (preferentially) polishing an insulating material with respect to a silicon material (stopper material). The polishing step can be a step of selectively (preferentially) polishing silicon oxide with respect to a silicon material (polysilicon, amorphous silicon, etc.). The polishing step can be a step of polishing silicon oxide using a silicon material (polysilicon, amorphous silicon, etc.) as a stopper material. As the stopper material, polysilicon, amorphous silicon, single crystal silicon, etc. can be given.

[0135] The polishing method of the present embodiment can also be a polishing method of a substrate having a first member including a silicon material, and a second member including an insulating material and disposed on the first member. The polishing step can have a step of polishing the second member until the first member is exposed using the polishing liquid of the present embodiment or a polishing liquid obtained by mixing the slurry in the polishing liquid set of the present embodiment with an additive liquid. The polishing step can also include a step of polishing the first member and the second member after the first member is exposed using the polishing liquid of the present embodiment or a polishing liquid obtained by mixing the slurry in the polishing liquid set of the present embodiment with an additive liquid.

[0136] As the insulating material, for example, an inorganic insulating material, an organic insulating material, or the like can be given. As the inorganic insulating material, for example, a silicon-based insulating material or the like can be given. As the silicon-based insulating material, for example, a silicon oxide, a silicon nitride, a fluorosilicate glass, an organosilicate glass, a hydrogen silsesquioxane, or the like can be given. As the silicon oxide, for example, a carbon-containing silicon oxide, a nitrogen-containing silicon oxide, a nitrogen-carbon-containing silicon oxide, or the like can be given. As the organic insulating material, for example, a wholly aromatic low dielectric constant insulating material can be given. The insulating material (silicon oxide or the like) can also be doped with an element such as phosphorus or boron.

[0137] The polishing step can also be a step of exposing the stopper by removing at least a part of the insulating member (member including an insulating material) using the polishing liquid of the present embodiment and CMP. For example, the polishing method of the present embodiment can also be a polishing method of a substrate having an insulating member on a surface. The polishing method of the present embodiment, for example, includes a substrate preparation step, a substrate disposition step, and a polishing step. In the substrate preparation step, for example, a substrate having a stopper and an insulating member disposed on the stopper is prepared. In the substrate disposition step, for example, the substrate is disposed so that the insulating member opposes the polishing pad. In the polishing step, for example, at least a part of the insulating member is removed. In the polishing step, for example, the polishing liquid is supplied between the polishing pad and the insulating member while the insulating member of the substrate having the insulating member is pressed against the polishing pad of the polishing table, and the substrate is relatively moved with respect to the polishing table, whereby at least a part of the insulating member is polished and removed. The shape of the insulating member is not particularly limited, and is, for example, a film shape (insulating film). The shape of the stopper is not particularly limited, and is, for example, a film shape (stopper film: for example, a polysilicon film or an amorphous silicon film).

[0138] As the substrate, for example, a substrate having an insulating member formed on a substrate (semiconductor substrate at a stage where a circuit element and a wiring pattern are formed, semiconductor substrate at a stage where a circuit element is formed, or the like) in the manufacture of a semiconductor element can be given.

[0139] By polishing the insulating material formed on the semiconductor substrate using the polishing liquid of the present embodiment, the unevenness on the surface of the insulating material can be eliminated and a smooth surface can be obtained over the entire surface of the substrate. The polishing method of the present embodiment can be used, for example, in a planarization process of an interlayer insulating film, a BPSG film, or the like, an STI formation process, or the like.

[0140] Figure 2 is a schematic cross-sectional view showing an example of a polishing method. As shown in (A) of Figure 2 , first, a substrate 100 having a wafer 1 on which an unevenness composed of a recessed portion (trench portion) and a protruding portion (active portion) is formed on a surface, a stop portion 2 formed on the protruding portion of the wafer 1, and an insulating member (for example, a silicon oxide film) 3 formed on the wafer 1 and the stop portion 2 so as to fill the unevenness of the surface of the wafer 1 are prepared.

[0141] The insulating member 3 can be formed, for example, by deposition using a plasma TEOS method.

[0142] Further, as shown in (B) of Figure 2 , the insulating member 3 is polished using the polishing liquid of the present embodiment and removed until the stop portion 2 on the protruding portion of the wafer 1 is exposed, thereby obtaining a substrate 200. In the substrate 200 after polishing, it is preferable that the recessed amount 6, which is a value obtained by subtracting the thickness 5 of the insulating member 3 in the trench portion from the depth 4 of the trench portion, be small. In the substrate 200, it is preferable that the number of recessed defects of the stop portion 2 be small.

[0143] As a polishing device, for example, a polishing device (trade name: Mirra-3400, Reflexion LK) manufactured by APPLIED MATERIALS, INC. and a polishing device (trade name: F-REX300) manufactured by SHIN-ETEK CORPORATION can be mentioned.

[0144] As a polishing pad, a general nonwoven fabric, a foam, a non-foam, or the like can be used. As a material of the polishing pad, a resin such as polyurethane, an acrylic resin, a polyester, an acrylic-ester copolymer, polytetrafluoroethylene, polypropylene, polyethylene, poly 4-methyl pentene, cellulose, a cellulose ester, a polyamide (for example, nylon (trade name) and aramid), a polyimide, a polyimide amide, a polysiloxane copolymer, an oxirane compound, a phenol resin, polystyrene, polycarbonate, an epoxy resin, or the like can be used. In particular, from the viewpoint of obtaining a more excellent polishing rate and planarity, the material of the polishing pad is preferably a foamed polyurethane and a non-foamed polyurethane. The polishing pad can be subjected to groove processing for retaining the polishing liquid.

[0145] The polishing conditions are not limited, and in order to prevent the substrate from flying, the rotation speed of the polishing stage is preferably 200 min -1From the viewpoint of sufficiently suppressing the occurrence of polishing damage, the polishing pressure (processing load) applied to the substrate is preferably 100 kPa or less at a rotation speed (rpm) of 1000 rpm or less. It is preferable that the polishing liquid be continuously supplied to the polishing pad using a pump or the like during the polishing. The amount of supply is not limited, and it is preferable that the surface of the polishing pad be always covered with the polishing liquid.

[0146] As for the substrate after the polishing, it is preferable that the substrate be sufficiently washed in running water to remove the particles adhering to the substrate. In the washing, dilute hydrofluoric acid or ammonia water can be used in addition to pure water, and a brush can be used in order to improve the washing efficiency. In addition, it is preferable that, after the washing, water droplets adhering to the substrate be wiped off using a rotary dewatering machine or the like, and then the substrate be dried.

[0147] As the substrate to be polished in the polishing method of the present embodiment, for example, a substrate having a single semiconductor such as a diode, a transistor, a compound semiconductor, a thermistor, a varister, a thyristor, or the like; a memory element such as a Dynamic Random Access Memory (DRAM), a Static Random Access Memory (SRAM), an Erasable Programmable Read Only Memory (EPROM), a Mask Read Only Memory, an Electrical Erasable Programmable Read Only Memory (EEPROM), a Flash Memory, or the like; a logic circuit element such as a microprocessor, a DSP, an ASIC, or the like; an integrated circuit element such as a Monolithic Microwave Integrated Circuit (MMIC) or the like; a hybrid integrated circuit (Hybrid IC), a light emitting diode, a charge-coupled element, or the like can be applied.

[0148] The polishing liquid of the present embodiment is not limited to the polishing of the insulating member or the like formed on a semiconductor substrate as described in the above-described embodiment, and can be applied to the polishing of inorganic insulating materials such as silicon oxide, glass, silicon nitride, or the like formed on a wiring board having a prescribed wiring; and materials mainly containing Al, Cu, Ti, TiN, W, Ta, TaN, or the like.

[0149] As the electronic component having the substrate polished by the polishing method of the present embodiment, various components can be listed. As the electronic component, not only semiconductor elements, but also optical glasses such as reticles, lenses, and prisms; inorganic conductive films such as indium tin oxide (ITO); optical integrated circuits including glass and crystalline materials; optical switching elements; optical waveguides; optical fiber end faces; optical monocrystals such as scintillators; solid laser monocrystals; sapphire substrates for blue laser light-emitting diodes (LEDs); semiconductor monocrystals such as SiC, GaP, and GaAs; glass substrates for magnetic disks; and magnetic heads can be listed. Among these electronic components, by polishing each layer using the polishing liquid of the present embodiment, high integration can be achieved and excellent characteristics can be exhibited.

[0150] <Defect suppression method>

[0151] The defect suppression method according to the present embodiment is a defect suppression method for suppressing generation of defects in polishing of a polished surface including a stopper material. The defect suppression method according to the present embodiment includes a polishing step of polishing the polished surface using the polishing liquid according to the present embodiment or a polishing liquid obtained by mixing the slurry in the polishing liquid kit according to the present embodiment and the additive liquid. In the defect suppression method according to the present embodiment, by using the first nitrogen-containing compound and the second nitrogen-containing compound as the defect suppressors, it is possible to suppress generation of defects in polishing of a polished surface including a silicon material (excluding silicon oxide), and in particular, it is possible to suppress generation of defects based on chemical action. The defect suppression method according to the present embodiment can further include, for example, an observation step of observing defects generated in the polished surface after the polishing step. The stopper material can include at least one selected from the group consisting of polycrystalline silicon, amorphous silicon, and monocrystalline silicon, and can include amorphous silicon.

[0152] Example

[0153] Hereinafter, the present application will be described by way of examples, but the present application is not limited to these examples.

[0154] <Preparation of polishing liquid components for CMP>

[0155] (Polishing grains: cerium oxide particles)

[0156] A commercially available cerium carbonate hydrate 40 kg was put into an alumina container, and calcined at 830°C for 2 hours in air, whereby 20 kg of yellowish white powder was obtained. When phase identification of the powder was performed by X-ray diffraction method, it was confirmed that it was cerium oxide. The obtained cerium oxide powder 20 kg was dry-pulverized using a jet mill, and cerium oxide powder including cerium oxide particles was obtained.

[0157] To measure the average particle size (D50) of the abrasive, a sample was prepared by mixing the abrasive with water so that its transmittance (H) during He-Ne laser measurement was 60% to 70%. The D50 of the sample was measured using a laser diffraction particle size analyzer (manufactured by Horiba, Ltd., trade name: LA-920, refractive index: 1.93, light source: He-Ne laser, absorption 0). The D50 value was 150 nm.

[0158] (additive)

[0159] The following compounds were prepared as additives.

[0160] [First nitrogen-containing compound]

[0161] 3-Aminopyridine, pyrazinamide, nicotinamide, and benzotriazole

[0162] [Second nitrogen-containing compound]

[0163] Polyoxyethylene laurylamine (HLB value = 13), polyoxyethylene stearylamine (HLB value = 15), polyoxyethylene tallow alkylamine (HLB value = 17), polyoxyethylene oleylamine (HLB value = 9), and polyoxyethylene alkylpropylenediamine (HLB value = 11)

[0164] [Other nitrogen-containing compounds]

[0165] Polyoxyethylene lauryl amine (HLB value = 6)

[0166] [Polymer compound (A)]

[0167] Polyacrylic acid with a weight average molecular weight of 2500 (calculated as sodium polyacrylate)

[0168] [Polymer compound (B)]

[0169] Polyoxyethylene polyoxypropylene glycol ether with a weight average molecular weight of 1200

[0170] [pH adjuster]

[0171] 25% ammonia water by mass

[0172] Preparation of CMP Polishing Slurry

[0173] The components prepared as described above were dispersed or dissolved in water to the contents shown in Table 1 or Table 2 to obtain a CMP polishing slurry. In the table, the pH adjuster content represents the ammonia content without water. The pH of the CMP polishing slurry was adjusted using the pH adjuster and measured using a PH81 (trade name, Model PH81, manufactured by Yokogawa Electric Corporation).

[0174] <Second nitrogen-containing compound liquid layer separation>

[0175] The CMP polishing liquid was visually confirmed, whereby the presence or absence of the second nitrogen-containing compound liquid layer separation in the CMP polishing liquid was confirmed. The results are shown in Tables 1 and 2.

[0176] <Defect evaluation>

[0177] As the number of defects, a test wafer for CMP evaluation having an amorphous silicon film on a silicon substrate was prepared.

[0178] In polishing of the test wafer for CMP evaluation, a polishing device (Reflexion LK manufactured by APPLIED MATERIALS) was used. The test wafer for CMP evaluation was set on a holder to which a suction pad for substrate mounting was attached. A porous polyurethane resin polishing pad (manufactured by Rohm and Haas Japan, model number IC1010) was attached to a polishing stage of the polishing device. The holder was placed on the polishing stage with the face having the amorphous silicon film facing down, and a processing load was set to 3.0 psi (about 21 kPa).

[0179] While the CMP polishing liquid (except for Comparative Examples 4 and 5) was dropped onto the polishing stage at a rate of 250 mL / min, the polishing stage and the test wafer for CMP evaluation were rotated at 93 min -1 , 87 min -1 , respectively, and polishing was performed for 180 seconds. The polished wafer was sufficiently washed with pure water and dried.

[0180] Using an optical microscope (manufactured by Olympus, trade name: DSX-510) under the conditions of an objective lens: 20x, and magnification: 1.5x, 5 sites in the central portion of the amorphous silicon film were observed, and the number of recess defects (recess defect number) was counted. The area of 1 field of view was 0.5 mm 2 . The average value of the 5 sites was obtained as the number of defects, and the number of defects of 0 to 4 was evaluated as "A", 5 to 9 as "B", and more than 10 as "C". The results are shown in Tables 1 and 2. From Tables 1 and 2, it was found that the generation of defects was suppressed in the examples. With respect to Comparative Examples 4 and 5, since the second nitrogen-containing compound liquid layer separation was confirmed, they were not suitable as the CMP polishing liquid, and therefore, defect evaluation was not performed.

[0181] [Table 1]

[0182]

[0183] [Table 2]

[0184]

[0185] Legend

[0186] 1 - wafer, 2 - stop, 3 - insulating member, 4 - depth, 5 - thickness, 6 - recess amount, 100, 200 - base.

Claims

1. A polishing liquid comprising abrasive grains, a first nitrogen-containing compound, a second nitrogen-containing compound and water, wherein: The first nitrogen-containing compound comprises at least one selected from the group consisting of (I) a compound having an aromatic ring containing one nitrogen atom in the ring and a hydroxyl group, (II) a compound having an aromatic ring containing one nitrogen atom in the ring and a functional group containing a nitrogen atom, (III) a compound having a six-membered ring containing two nitrogen atoms in the ring, (IV) a compound having a benzene ring and a ring containing a nitrogen atom in the ring, and (V) a compound having a benzene ring to which two or more functional groups containing nitrogen atoms are bonded. The second nitrogen-containing compound has an HLB value of 7 or greater.

2. The polishing liquid according to claim 1, wherein The molecular weight of the first nitrogen-containing compound is less than 200.

3. The polishing liquid according to claim 1, wherein The first nitrogen-containing compound comprises the compound (II).

4. The polishing liquid according to claim 3, wherein The aromatic ring of the compound (II) includes a pyridine ring.

5. The polishing liquid according to claim 3, wherein The functional group of the compound (II) includes at least one selected from the group consisting of an amino group, an amide group, and a sulfonamide group.

6. The polishing liquid according to claim 1, wherein The first nitrogen-containing compound comprises the compound (III).

7. The polishing liquid according to claim 6, wherein The 6-membered ring of the compound (III) includes a pyrazine ring.

8. The polishing liquid according to claim 1, wherein The first nitrogen-containing compound comprises the compound (IV).

9. The polishing liquid according to claim 8, wherein In the compound (IV), the ring containing the nitrogen atom includes at least one selected from the group consisting of a triazole ring and a pyrazolone ring.

10. The polishing liquid according to claim 1, wherein The first nitrogen-containing compound includes at least one selected from the group consisting of aminopyridine, picoline amide, and nicotinamide.

11. The polishing liquid according to claim 1, wherein The first nitrogen-containing compound comprises niacinamide.

12. The polishing liquid according to claim 1, wherein The first nitrogen-containing compound comprises aminopyridine.

13. The polishing liquid according to claim 12, wherein The aminopyridine includes at least one selected from the group consisting of 2-aminopyridine, 3-aminopyridine, and 4-aminopyridine.

14. The polishing liquid according to claim 1, wherein The first nitrogen-containing compound includes at least one selected from the group consisting of pyrazine, pyrazinamide, 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, 2,3-diethylpyrazine, and 2,3,5,6-tetramethylpyrazine.

15. The polishing liquid according to claim 1, wherein The first nitrogen-containing compound comprises pyrazinamide.

16. The polishing liquid according to claim 1, wherein The first nitrogen-containing compound includes at least one selected from the group consisting of benzotriazole and 1-phenyl-3-pyrazolidinone.

17. The polishing liquid according to claim 1, wherein The content of the first nitrogen-containing compound is 0.001 to 10% by mass.

18. The polishing liquid according to claim 1, wherein The content of the first nitrogen-containing compound is 0.01 to 1% by mass.

19. The polishing liquid according to claim 1, wherein The molecular weight of the second nitrogen-containing compound is 200 or greater.

20. The polishing liquid according to claim 1, wherein The HLB value of the second nitrogen-containing compound is 7-20.

21. The polishing liquid according to claim 1, wherein The HLB value of the second nitrogen-containing compound is 9-17.

22. The polishing liquid according to claim 1, wherein The HLB value of the second nitrogen-containing compound is 10-15.

23. The polishing liquid according to claim 1, wherein The second nitrogen-containing compound includes a compound represented by the following general formula (X), Where R 1 、R 2 and R 3 Each independently represents a polyoxyalkylene group or a hydrocarbon group which may have a substituent.

24. The polishing liquid according to claim 23, wherein The second nitrogen-containing compound comprises R 1 、R 2 and R 3 A compound in which one or two of the groups are polyoxyalkylene groups.

25. The polishing liquid according to claim 23, wherein The second nitrogen-containing compound comprises R 1 、R 2 and R 3 A compound in which one or two of the groups are polyoxyethylene.

26. The polishing liquid according to claim 23, wherein The hydrocarbon group is an alkyl group.

27. The polishing liquid according to claim 23, wherein The hydrocarbon group has 3 to 30 carbon atoms.

28. The polishing liquid according to claim 23, wherein The hydrocarbon group has 12 to 18 carbon atoms.

29. The polishing liquid according to claim 1, wherein The second nitrogen-containing compound comprises a polyetheramine.

30. The polishing liquid according to claim 29, wherein The polyetheramine includes at least one selected from the group consisting of polyoxyethylene alkylamine, polyoxyethylene polyoxypropylene laurylamine, and polyoxyethylene alkylpropylenediamine.

31. The polishing liquid according to claim 30, wherein The polyoxyethylene alkylamine includes at least one selected from the group consisting of polyoxyethylene oleylamine, polyoxyethylene laurylamine, polyoxyethylene stearylamine, polyoxyethylene tallow alkylamine, and polyoxyethylene alkyl (coconut) amine.

32. The polishing liquid according to claim 1, wherein The second nitrogen-containing compound includes at least one selected from the group consisting of polyoxyethylene oleylamine, polyoxyethylene laurylamine, polyoxyethylene stearylamine, polyoxyethylene tallow alkylamine, and polyoxyethylene alkylpropylenediamine.

33. The polishing liquid according to claim 1, wherein The content of the second nitrogen-containing compound is 0.0001 to 1.0 mass %.

34. The polishing liquid according to claim 1, wherein The content of the second nitrogen-containing compound is 0.0001 to 0.01 mass %. 35 . The polishing liquid according to claim 1 , further comprising a polymer compound (A) having at least one selected from the group consisting of a carboxyl group and a carboxylate group.

36. The polishing liquid according to claim 35, wherein The polymer compound (A) includes a polymer obtained by polymerizing at least one monomer selected from the group consisting of acrylic acid and methacrylic acid, or a salt thereof.

37. The polishing liquid according to claim 35, wherein The polymer compound (A) comprises at least one selected from the group consisting of homopolymers of acrylic acid, homopolymers of methacrylic acid, copolymers of acrylic acid and methacrylic acid, copolymers of acrylic acid or methacrylic acid with other monomers, copolymers of acrylic acid and methacrylic acid with other monomers, and salts thereof.

38. The polishing liquid according to claim 35, wherein The weight average molecular weight of the polymer compound (A) is 2,000 to 7,000.

39. The polishing liquid according to claim 35, wherein The content of the polymer compound (A) is 0.1 to 0.5% by mass.

40. The polishing liquid according to claim 1, further comprising a nonionic polymer compound (B).

41. The polishing liquid according to claim 40, wherein The polymer compound (B) contains a polyoxyalkylene derivative.

42. The polishing liquid according to claim 40, wherein The polymer compound (B) contains polyoxyalkylene polyglyceryl ether.

43. The polishing liquid according to claim 40, wherein The polymer compound (B) contains polyoxyethylene polyoxypropylene glycol ether.

44. The polishing liquid according to claim 40, wherein The weight average molecular weight of the polymer compound (B) is 500 to 5000.

45. The polishing liquid according to claim 40, wherein The content of the polymer compound (B) is 0.03 to 0.1% by mass. The polishing liquid according to claim 1 , further comprising a basic compound.

47. The polishing liquid according to claim 46, wherein The basic compound comprises ammonia.

48. The polishing liquid according to claim 46, wherein The content of the basic compound is 0.04 mol / kg or less.

49. The polishing liquid according to claim 1, wherein The abrasive grains contain a cerium compound.

50. The polishing liquid according to claim 1, wherein The abrasive grains include cerium oxide.

51. The polishing liquid according to claim 1, wherein The average particle size of the abrasive particles is 50 to 300 nm.

52. The polishing liquid according to claim 1, wherein The content of the abrasive grains is 0.01 to 20% by mass.

53. The polishing liquid according to claim 1, wherein The content of the abrasive grains is 0.2 to 1% by mass.

54. The polishing liquid according to claim 1, wherein The pH value exceeds 4.

0.

55. The polishing liquid according to claim 1, wherein The pH value is 5.0~6.

5.

56. A polishing liquid set, wherein: The polishing liquid according to any one of claims 1 to 55 is stored as a first liquid and a second liquid. The first liquid contains the abrasive and water, The second liquid includes the first nitrogen-containing compound, the second nitrogen-containing compound, and water.

57. A grinding method comprising the following steps: The surface to be polished is polished using the polishing liquid according to any one of claims 1 to 55 or the polishing liquid obtained by mixing the first liquid and the second liquid in the polishing liquid set according to claim 56.

58. The grinding method according to claim 57, wherein The polished surface includes at least one selected from the group consisting of polycrystalline silicon, amorphous silicon, and single crystal silicon.

59. A defect suppression method for suppressing the generation of defects during polishing of a polished surface including a stopper material, the method comprising the following steps: The surface to be polished is polished using the polishing liquid according to any one of claims 1 to 55 or the polishing liquid obtained by mixing the first liquid and the second liquid in the polishing liquid set according to claim 56.

60. The defect suppression method according to claim 59, wherein: The stopper material includes at least one selected from the group consisting of polycrystalline silicon, amorphous silicon, and single crystal silicon.

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