RINSE COMPOSITION AND RINSE METHOD

Abstract

To provide a composition for rinse, which contains a water-soluble polymer and no polishing grains, and which can decrease the number of defects of target objects after polishing.SOLUTION: A composition for rinse, which is provided according to the present invention, comprises a water-soluble polymer, of which the desorption parameter given by formula (I) below is 150 or larger, and no abrasive grains. W1 / W0×100 (I), where W0 is a static contact angle, to deionized water, of a pre-SC-1 treatment wafer obtained by coating a surface of a single crystal silicon wafer with an aqueous solution of the water-soluble polymer and then rinsing the wafer by water, and W1 is a static contact angle, to deionized water, of a post SC-1 treatment wafer obtained by executing, on the pre-SC-1 treatment wafer, a cleaning process of performing a treatment with an SC-1 cleaning liquid of a room temperature for 10 seconds.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a rinsing composition used for rinsing an object to be polished after polishing, and a method for rinsing an object to be polished using the rinsing composition. [Background technology]

[0002] Precision polishing is performed on the surfaces of materials such as metals, semi-metals, non-metals, and oxides thereof using a polishing composition containing abrasive grains. For example, the surface of a silicon wafer used as a component of a semiconductor device is generally finished into a high-quality mirror surface through a lapping process (rough polishing process) and a polishing process (precise polishing process). The polishing process typically includes a preliminary polishing process (preliminary polishing process) and a finish polishing process (final polishing process). Patent documents 1 to 3 are cited as technical documents related to the polishing of semiconductor substrates such as silicon wafers. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-183478 A [Patent Document 2] International Publication No. 2016 / 129215 [Patent Document 3] Patent No. 6193959 Summary of the Invention [Problem to be solved by the invention]

[0004] When an object to be polished is polished using a polishing composition containing abrasive grains, the abrasive grains contained in the polishing composition usually adhere to the surface of the object to be polished after polishing. Since there are various problems if the abrasive grains remain attached to the surface of the object to be polished, it is common to rinse the surface of the object to be polished after polishing with a rinsing composition in order to remove the attached abrasive grains. In recent years, the demands for surface quality after polishing in a finish polishing process (particularly, a finish polishing process for semiconductor substrates such as silicon wafers and other substrates) have become higher. In order to achieve a high-quality surface after polishing, a rinsing composition used after polishing is required to have the performance of protecting the surface of the object to be polished well during rinsing, reducing the number of PIDs (Polish Induced Defects) after polishing, and reliably removing abrasive grains and the like adhering to the surface of the object to be polished after rinsing. However, conventional rinsing compositions do not fully satisfy these demands, and there is still room for improvement.

[0005] Therefore, an object of the present invention is to provide a rinsing composition that contains a water-soluble polymer and does not contain abrasive grains, and that can reduce the number of defects on an object to be polished after polishing. Another related object is to provide a method for rinsing an object to be polished after polishing using the rinsing composition.

[0006] In this specification, reducing the number of defects refers to reducing the number of defects called LLS (Localized Light Scatterer). A surface defect inspection device is used to measure LLS. A typical surface defect inspection device detects the presence and size of defects by irradiating the surface of the object to be polished with light such as a laser beam and receiving and analyzing the reflected light as a signal. The LLS detected by the surface defect inspection device include foreign matter and residues on the object to be polished that were not completely removed in the polishing process, rinsing process, and cleaning process, that is, PIDs and abrasive grain residues. A defect review SEM (Scanning Electron Microscope) or the like is used to analyze the defect types of the detected LLS. [Means for solving the problem]

[0007] The rinse composition provided by this specification is a rinse composition containing a water-soluble polymer and no abrasive grains, wherein the water-soluble polymer is a compound represented by the following formula (I): W1 / W0×100 (I); The composition is characterized in that it contains a water-soluble polymer A having a desorption parameter of 150 or more, as expressed by the formula: W0 in the above formula (I) is the static contact angle of the wafer before SC-1 cleaning treatment, obtained by applying an aqueous solution of the water-soluble polymer to the surface of a silicon wafer and then rinsing with water, to deionized water. W1 in the above formula (I) is the static contact angle of the wafer after SC-1 treatment, obtained by subjecting the wafer before SC-1 cleaning treatment to cleaning treatment (specifically, cleaning treatment for 10 seconds with SC-1 cleaning solution at room temperature containing 29% ammonia water, 31% hydrogen peroxide solution, and water in a volume ratio of 0.5:0.5:8) to deionized water. In this specification, the contact angle is expressed in units of "degrees (°)". In this specification, the concentration and content are expressed by weight unless otherwise specified. Rinsing with a rinsing composition containing the water-soluble polymer A can reduce the number of defects on the polishing object. For example, the number of abrasive grain residues can be reduced, and the number of PIDs can be reduced.

[0008] In some embodiments of the rinsing composition disclosed herein, the rinsing composition further comprises a water-soluble polymer B having a desorption parameter represented by the above formula (I) of less than 150. With such a rinsing composition, the number of defects on the object to be polished can be further effectively reduced.

[0009] A water-soluble polymer containing a nitrogen atom-containing polymer can be preferably used as the water-soluble polymer A. In this embodiment, the number of defects on the polishing object after rinsing can be suitably reduced.

[0010] In some embodiments of the rinsing composition disclosed herein, the rinsing composition further comprises a surfactant. In such a rinsing composition, the number of defects on the surface of the polishing object after rinsing can be further effectively reduced.

[0011] In some embodiments of the rinsing composition disclosed herein, the rinsing composition further comprises a basic compound. In such a configuration of the rinsing composition, the number of defects on the object to be polished can be suitably reduced.

[0012] This specification also provides a rinsing method including a rinsing step of supplying a rinsing liquid containing any of the rinsing compositions disclosed herein to rinse an object to be polished that has been polished in a polishing step using a polishing composition containing abrasive grains. The rinsing method can effectively reduce the number of defects on the object to be polished after rinsing.

[0013] In some aspects of the rinsing method disclosed herein, it is preferable that in the rinsing step, the rinsing liquid is supplied to the object to be polished on the platen of the polishing apparatus used in the polishing step. In such aspects, the effect of reducing the number of defects in the object to be polished can be more suitably exhibited.

[0014] The rinsing method disclosed herein can be preferably used for rinsing silicon wafers polished with a polishing composition containing abrasive grains. By performing rinsing using this method after a polishing process, surface defects can be reduced, and a high-quality silicon wafer surface can be preferably achieved. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Preferred embodiments of the present invention will be described below. Note that matters other than those specifically mentioned in this specification that are necessary for carrying out the present invention can be understood as design matters for a person skilled in the art based on the prior art in the relevant field. The present invention can be carried out based on the contents disclosed in this specification and the technical common sense in the relevant field.

[0016] <Water-soluble polymer> The rinse composition disclosed herein includes a water-soluble polymer. The water-soluble polymer can be useful for protecting the surface of the object to be polished. As the water-soluble polymer, a polymer having at least one functional group selected from a cationic group, an anionic group, and a nonionic group in the molecule can be used alone or in combination of two or more. More specifically, for example, one or more polymers selected from polymers having a hydroxyl group, a carboxyl group, an acyloxy group, a sulfo group, an amide structure, an imide structure, a vinyl structure, a heterocyclic structure, etc. in the molecule can be used as the water-soluble polymer. The water-soluble polymer can include water-soluble polymers such as nitrogen atom-containing polymers, vinyl alcohol-based polymers, polymers containing oxyalkylene units, cellulose derivatives, and starch derivatives.

[0017] As the polymer containing a nitrogen atom, both a polymer containing a nitrogen atom in the main chain and a polymer having a nitrogen atom in a side chain functional group (pendant group) can be used. Examples of the polymer containing a nitrogen atom in the main chain include homopolymers and copolymers of N-acyl alkylene imine type monomers. Specific examples of N-acyl alkylene imine type monomers include N-acetyl ethylene imine, N-propionyl ethylene imine, and the like. Examples of the polymer having a nitrogen atom in the pendant group include, for example, polymers containing N-vinyl type monomer units. For example, homopolymers and copolymers of N-vinyl pyrrolidone can be employed. Non-limiting examples of the polymer containing a nitrogen atom include polymers containing N-vinyl type monomer units such as N-vinyl lactams and N-vinyl chain amides; imine derivatives; polymers containing N-(meth)acryloyl type monomer units; and the like.

[0018] Examples of polymers containing N-vinyl monomer units include polymers containing repeating units derived from monomers having nitrogen-containing heterocycles. An example of a nitrogen-containing heterocycle is a lactam ring. Examples of polymers containing such repeating units include homopolymers and copolymers of N-vinyl lactam monomers, and homopolymers and copolymers of N-vinyl linear amides. The N-vinyl lactam monomer copolymer may be, for example, a copolymer in which the copolymerization ratio of N-vinyl lactam monomer exceeds 50% by weight. The N-vinyl linear amide copolymer may be, for example, a copolymer in which the copolymerization ratio of N-vinyl linear amide exceeds 50% by weight.

[0019] In this specification, unless otherwise specified, copolymer refers to various copolymers such as random copolymer, alternating copolymer, block copolymer, graft copolymer, etc. In order to protect the surface of the polishing object more uniformly during rinsing, random copolymer can be preferably adopted in some embodiments.In particular, when copolymer is used as water-soluble polymer, random copolymer can be preferably used as the copolymer.

[0020] Specific examples of N-vinyl lactam type monomers include N-vinyl pyrrolidone (VP), N-vinyl piperidone, N-vinyl morpholinone, N-vinyl caprolactam (VC), N-vinyl-1,3-oxazin-2-one, and N-vinyl-3,5-morpholinedione. Specific examples of polymers containing N-vinyl lactam type monomer units include polyvinyl pyrrolidone, polyvinyl caprolactam, random copolymers of VP and VC, random copolymers of one or both of VP and VC with other vinyl monomers, block copolymers and graft copolymers containing polymer chains containing one or both of VP and VC. The other vinyl monomers may be, for example, acrylic monomers, vinyl ester monomers, and the like. Here, the acrylic monomer refers to a monomer having a (meth)acryloyl group. Specific examples of N-vinyl chain amides include N-vinyl acetamide, N-vinyl propionic acid amide, and N-vinyl butyric acid amide.

[0021] Examples of the polymer containing N-(meth)acryloyl type monomer units include homopolymers and copolymers of N-(meth)acryloyl type monomers. Examples of the N-(meth)acryloyl type monomers include linear amides having N-(meth)acryloyl groups and cyclic amides having N-(meth)acryloyl groups. The copolymers of the N-(meth)acryloyl type monomers may be, for example, copolymers in which the copolymerization ratio of N-(meth)acryloyl type monomers exceeds 50% by weight.

[0022] Examples of chain amides having N-(meth)acryloyl groups include (meth)acrylamide; N-alkyl(meth)acrylamides such as N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-propyl(meth)acrylamide, N-isopropyl(meth)acrylamide, and Nn-butyl(meth)acrylamide; and N,N-dialkyl(meth)acrylamides such as N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-dipropyl(meth)acrylamide, N,N-diisopropyl(meth)acrylamide, and N,N-di(n-butyl)(meth)acrylamide. Examples of polymers containing chain amides having N-(meth)acryloyl groups as monomer units include homopolymers of N-isopropylacrylamide and copolymers of N-isopropylacrylamide. The copolymers of N-isopropylacrylamide may be, for example, copolymers in which the copolymerization ratio of N-isopropylacrylamide exceeds 50% by weight.

[0023] Examples of the cyclic amide having an N-(meth)acryloyl group include N-(meth)acryloylmorpholine, N-(meth)acryloylpyrrolidine, etc. Examples of the polymer containing the cyclic amide having an N-(meth)acryloyl group as a monomer unit include a homopolymer of N-acryloylmorpholine and a copolymer of N-acryloylmorpholine. The copolymer of N-acryloylmorpholine may be, for example, a copolymer in which the copolymerization ratio of N-acryloylmorpholine exceeds 50% by weight.

[0024] As the vinyl alcohol-based polymer, a water-soluble organic material (typically a water-soluble polymer) containing a vinyl alcohol unit as a repeating unit is used. Here, the vinyl alcohol unit (hereinafter also referred to as "VA unit") is a structural portion represented by the following chemical formula: -CH2-CH(OH)-;. The vinyl alcohol-based polymer may contain only VA units as repeating units, or may contain repeating units other than VA units (hereinafter also referred to as "non-VA units") in addition to VA units. The vinyl alcohol-based polymer may be a random copolymer containing VA units and non-VA units, or may be a block copolymer or a graft copolymer. The vinyl alcohol-based polymer may contain only one type of non-VA unit, or may contain two or more types of non-VA units.

[0025] The vinyl alcohol-based polymer used in the rinse composition disclosed herein may be unmodified polyvinyl alcohol (unmodified PVA) or modified polyvinyl alcohol (modified PVA). Here, the unmodified PVA refers to a vinyl alcohol-based polymer that is produced by hydrolysis (saponification) of polyvinyl acetate and does not substantially contain repeating units other than repeating units (-CH2-CH(OCOCH3)-) and VA units, which are vinyl polymerized structures of vinyl acetate. The degree of saponification of the unmodified PVA may be, for example, 60% or more, and from the viewpoint of water solubility, may be 70% or more, 80% or more, or 90% or more. In some embodiments, unmodified PVA with a degree of saponification of 95% or more or 98% or more may be preferably adopted as the water-soluble polymer compound.

[0026] The vinyl alcohol polymer may be a modified PVA containing VA units and non-VA units (e.g., non-VA units having at least one structure selected from an oxyalkylene group, a carboxy group, a sulfo group, an amino group, a hydroxyl group, an amide group, an imide group, a nitrile group, an ether group, an ester group, and salts thereof). Examples of non-VA units that may be contained in the modified PVA include, but are not limited to, repeating units derived from N-vinyl monomers and N-(meth)acryloyl monomers described below, repeating units derived from ethylene, repeating units derived from alkyl vinyl ethers, and repeating units derived from vinyl esters of monocarboxylic acids having 3 or more carbon atoms. A suitable example of the N-vinyl monomer is N-vinylpyrrolidone. A suitable example of the N-(meth)acryloyl monomer is N-(meth)acryloylmorpholine. The alkyl vinyl ether may be, for example, a vinyl ether having an alkyl group having 1 to 10 carbon atoms, such as propyl vinyl ether, butyl vinyl ether, or 2-ethylhexyl vinyl ether. The vinyl ester of a monocarboxylic acid having 3 or more carbon atoms may be, for example, a vinyl ester of a monocarboxylic acid having 3 to 7 carbon atoms, such as vinyl propanoate, vinyl butanoate, vinyl pentanoate, or vinyl hexanoate.

[0027] The vinyl alcohol polymer may be a modified PVA in which a part of the VA units contained in the vinyl alcohol polymer is acetalized with an aldehyde. Examples of the aldehyde include formaldehyde; linear or branched alkyl aldehydes such as acetaldehyde, propionaldehyde, n-butylaldehyde, isobutylaldehyde, t-butylaldehyde, and hexylaldehyde; alicyclic or aromatic aldehydes such as cyclohexanecarbaldehyde and benzaldehyde; and the like. These may be used alone or in combination of two or more. In addition, except for formaldehyde, one or more hydrogen atoms may be substituted with halogen or the like. Among these, linear or branched alkyl aldehydes are preferred because they are highly soluble in water and easily undergo acetalization reaction. Among these, acetaldehyde, n-propylaldehyde, n-butylaldehyde, and n-pentylaldehyde are particularly preferred examples of the aldehyde. As the aldehyde, in addition to the above, aldehyde compounds having 8 or more carbon atoms, such as 2-ethylhexylaldehyde, nonylaldehyde, and decylaldehyde, may be used. As the vinyl alcohol-based polymer, a cation-modified polyvinyl alcohol having a cationic group such as a quaternary ammonium structure introduced therein may be used. Examples of the cation-modified polyvinyl alcohol include those having a cationic group derived from a monomer having a cationic group such as a diallyldialkylammonium salt or an N-(meth)acryloylaminoalkyl-N,N,N-trialkylammonium salt introduced therein.

[0028] The ratio of the number of moles of VA units to the number of moles of all repeating units constituting the vinyl alcohol-based polymer may be, for example, 5% or more, 10% or more, 20% or more, or 30% or more. Although not particularly limited, in some embodiments, the ratio of the number of moles of VA units may be 50% or more, 65% or more, 75% or more, 80% or more, or 90% or more (for example, 95% or more, or 98% or more). Substantially 100% of the repeating units constituting the vinyl alcohol-based polymer may be VA units. Here, "substantially 100%" means that at least intentionally, the vinyl alcohol-based polymer does not contain non-VA units, and typically the ratio of the number of moles of non-VA units to the number of moles of all repeating units is less than 2% (for example, less than 1%), including the case of 0%. In some other embodiments, the ratio of the number of moles of VA units to the number of moles of all repeating units constituting the vinyl alcohol-based polymer may be, for example, 95% or less, 90% or less, 80% or less, or 70% or less.

[0029] The content of VA units in the vinyl alcohol-based polymer (content based on weight) may be, for example, 5% by weight or more, 10% by weight or more, 20% by weight or more, or 30% by weight or more. Although not particularly limited, in some embodiments, the content of the VA units may be 50% by weight or more (e.g., more than 50% by weight), 70% by weight or more, or 80% by weight or more (e.g., 90% by weight or more, 95% by weight or more, or 98% by weight or more). Substantially 100% by weight of the repeating units constituting the vinyl alcohol-based polymer may be VA units. Here, "substantially 100% by weight" means that at least intentionally, non-VA units are not contained as repeating units constituting the vinyl alcohol-based polymer, and typically means that the content of non-VA units in the vinyl alcohol-based polymer is less than 2% by weight (e.g., less than 1% by weight). In some other embodiments, the content of VA units in the vinyl alcohol-based polymer may be, for example, 95% by weight or less, 90% by weight or less, 80% by weight or less, or 70% by weight or less.

[0030] The vinyl alcohol-based polymer may contain multiple polymer chains with different VA unit contents in the same molecule. Here, the polymer chain refers to a portion (segment) that constitutes a part of a single polymer molecule. For example, the vinyl alcohol-based polymer may contain polymer chain A with a VA unit content of more than 50% by weight and polymer chain B with a VA unit content of less than 50% by weight (i.e., a non-VA unit content of more than 50% by weight) in the same molecule.

[0031] The polymer chain A may contain only VA units as repeat units, or may contain non-VA units in addition to VA units. The content of VA units in the polymer chain A may be 60% by weight or more, 70% by weight or more, 80% by weight or more, or 90% by weight or more. In some embodiments, the content of VA units in the polymer chain A may be 95% by weight or more, or 98% by weight or more. Substantially 100% by weight of the repeat units constituting the polymer chain A may be VA units.

[0032] The polymer chain B may contain only non-VA units as repeat units, or may contain VA units in addition to non-VA units. The content of non-VA units in the polymer chain B may be 60% by weight or more, 70% by weight or more, 80% by weight or more, or 90% by weight or more. In some embodiments, the content of non-VA units in the polymer chain B may be 95% by weight or more, or 98% by weight or more. Substantially 100% by weight of the repeat units constituting the polymer chain B may be non-VA units.

[0033] Examples of vinyl alcohol-based polymers containing polymer chain A and polymer chain B in the same molecule include block copolymers and graft copolymers containing these polymer chains. The graft copolymer may be a graft copolymer having a structure in which polymer chain B (side chain) is grafted to polymer chain A (main chain), or a graft copolymer having a structure in which polymer chain A (side chain) is grafted to polymer chain B (main chain). In one embodiment, a vinyl alcohol-based polymer having a structure in which polymer chain B is grafted to polymer chain A can be used.

[0034] Examples of the polymer chain B include a polymer chain having a repeating unit derived from an N-vinyl type monomer as a main repeating unit, a polymer chain having a repeating unit derived from an N-(meth)acryloyl type monomer as a main repeating unit, a polymer chain having an oxyalkylene unit as a main repeating unit, etc. In this specification, the main repeating unit refers to a repeating unit contained in an amount of more than 50% by weight, unless otherwise specified.

[0035] A preferred example of the polymer chain B is a polymer chain having an N-vinyl type monomer as a main repeating unit, i.e., an N-vinyl polymer chain. The content of the repeating unit derived from the N-vinyl type monomer in the N-vinyl polymer chain is typically more than 50% by weight, and may be 70% by weight or more, 85% by weight or more, or 95% by weight or more. Substantially all of the polymer chain B may be a repeating unit derived from an N-vinyl type monomer.

[0036] In this specification, examples of N-vinyl type monomers include monomers having a nitrogen-containing heterocycle (e.g., lactam ring) and N-vinyl chain amides. Specific examples of N-vinyl lactam type monomers include N-vinyl pyrrolidone, N-vinyl piperidone, N-vinyl morpholinone, N-vinyl caprolactam, N-vinyl-1,3-oxazin-2-one, N-vinyl-3,5-morpholinedione, and the like. Specific examples of N-vinyl chain amides include N-vinyl acetamide, N-vinyl propionic acid amide, N-vinyl butyric acid amide, and the like. The polymer chain B may be, for example, an N-vinyl polymer chain in which more than 50% by weight (e.g., 70% by weight or more, 85% by weight or more, or 95% by weight or more) of its repeating units are N-vinyl pyrrolidone units. Substantially all of the repeating units constituting the polymer chain B may be N-vinyl pyrrolidone units.

[0037] Another example of the polymer chain B is a polymer chain having a repeating unit derived from an N-(meth)acryloyl type monomer as a main repeating unit, i.e., an N-(meth)acryloyl-based polymer chain. The content of the repeating unit derived from an N-(meth)acryloyl type monomer in the N-(meth)acryloyl-based polymer chain is typically more than 50% by weight, and may be 70% by weight or more, 85% by weight or more, or 95% by weight or more. Substantially all of the polymer chain B may be a repeating unit derived from an N-(meth)acryloyl type monomer.

[0038] In this specification, examples of N-(meth)acryloyl type monomers include chain amides having an N-(meth)acryloyl group and cyclic amides having an N-(meth)acryloyl group. Examples of chain amides having an N-(meth)acryloyl group include (meth)acrylamide; N-alkyl(meth)acrylamides such as N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-propyl(meth)acrylamide, N-isopropyl(meth)acrylamide, and Nn-butyl(meth)acrylamide; and N,N-dialkyl(meth)acrylamides such as N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-dipropyl(meth)acrylamide, N,N-diisopropyl(meth)acrylamide, and N,N-di(n-butyl)(meth)acrylamide. Examples of cyclic amides having an N-(meth)acryloyl group include N-(meth)acryloylmorpholine and N-(meth)acryloylpyrrolidine.

[0039] Another example of the polymer chain B is a polymer chain containing an oxyalkylene unit as a main repeating unit, i.e., an oxyalkylene-based polymer chain. The content of the oxyalkylene unit in the oxyalkylene-based polymer chain is typically more than 50% by weight, and may be 70% by weight or more, 85% by weight or more, or 95% by weight or more. Substantially all of the repeating units contained in the polymer chain B may be oxyalkylene units.

[0040] Examples of oxyalkylene units include oxyethylene units, oxypropylene units, oxybutylene units, etc. Each of these oxyalkylene units may be a repeating unit derived from the corresponding alkylene oxide. The oxyalkylene units contained in the oxyalkylene polymer chain may be one type or two or more types. For example, the oxyalkylene polymer chain may contain a combination of an oxyethylene unit and an oxypropylene unit. In the oxyalkylene polymer chain containing two or more types of oxyalkylene units, the oxyalkylene units may be a random copolymer of the corresponding alkylene oxide, or may be a block copolymer or a graft copolymer.

[0041] Further examples of polymer chain B include polymer chains containing a repeating unit derived from an alkyl vinyl ether (e.g., a vinyl ether having an alkyl group having from 1 to 10 carbon atoms), a polymer chain containing a repeating unit derived from a monocarboxylic acid vinyl ester (e.g., a vinyl ester of a monocarboxylic acid having from 3 or more carbon atoms), a polymer chain in which a part of the VA units has been acetalized with an aldehyde (e.g., an alkyl aldehyde having an alkyl group having from 1 to 7 carbon atoms), and a polymer chain into which a cationic group (e.g., a cationic group having a quaternary ammonium structure) has been introduced.

[0042] As the vinyl alcohol-based polymer in the rinse composition disclosed herein, non-modified PVA may be used, modified PVA may be used, or non-modified PVA and modified PVA may be used in combination. In the embodiment in which non-modified PVA and modified PVA are used in combination, the amount of modified PVA used relative to the total amount of vinyl alcohol-based polymer contained in the rinse composition may be, for example, less than 50% by weight, 30% by weight or less, 10% by weight or less, 5% by weight or less, or 1% by weight or less. The rinse composition disclosed herein may be preferably implemented, for example, in an embodiment in which only one or more kinds of non-modified PVA are used as the vinyl alcohol-based polymer.

[0043] Examples of polymers containing oxyalkylene units include polyethylene oxide (PEO), block copolymers of ethylene oxide (EO) and propylene oxide (PO) or butylene oxide (BO), and random copolymers of EO and PO or BO. Among these, block copolymers of EO and PO or random copolymers of EO and PO are preferred. The block copolymers of EO and PO may be diblock copolymers or triblock copolymers containing a PEO block and a polypropylene oxide (PPO) block. Examples of the triblock copolymers include PEO-PPO-PEO type triblock copolymers and PPO-PEO-PPO type triblock copolymers. Among these, PEO-PPO-PEO type triblock copolymers are more preferred. In a block or random copolymer of EO and PO, the molar ratio of EO to PO (EO / PO) constituting the copolymer is preferably greater than 1, more preferably 2 or more, and even more preferably 3 or more (e.g., 5 or more), from the viewpoints of solubility in water, washability, etc.

[0044] Cellulose derivatives are polymers containing β-glucose units as the main repeating unit, such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose (HEC), methylhydroxyethyl cellulose, etc. Starch derivatives are polymers containing α-glucose units as the main repeating unit, such as pregelatinized starch, pullulan, carboxymethyl starch, cyclodextrin, etc.

[0045] (Water-soluble polymer A) The rinsing composition disclosed herein is characterized by containing, as the water-soluble polymer, at least one water-soluble polymer A having a desorption parameter of 150 or more. The desorption parameter is determined as a percentage of the static contact angle W1 of the surface of a silicon wafer coated with the water-soluble polymer to be evaluated, with deionized water, relative to the static contact angle W0 of the surface of the silicon wafer coated with the water-soluble polymer to be evaluated, with deionized water. More specifically, the desorption parameter is measured by the following method.

[0046] [Method of measuring desorption parameters] (1) Commercially available silicon single crystal wafers with a diameter of 300 mm (conductivity type: P type, crystal orientation: <100> A test piece (hereinafter simply referred to as the test piece) cut into a size of 30 mm x 60 mm from a COP (Crystal Originated Particle: crystal defect-free) is first treated with an SC-1 cleaning solution, and then immersed in a 2.5% hydrogen fluoride (HF) aqueous solution for 30 seconds as a pretreatment to remove the surface oxide film. (2) Prepare a test solution containing the water-soluble polymer to be evaluated at a concentration of 0.18% and adjusted to pH 10 with ammonia. Place the test piece in a petri dish and pour in the test solution so that the test piece is immersed. Place a polyester and cellulose mixed nonwoven fabric on top of the test piece and rotate it at 60 rpm for 1 minute while applying a load of 1 kg. After applying the test solution to the test piece in this way, immerse the test piece in deionized water to remove excess water-soluble polymer. (3) The test piece is immersed in a 2.5% HF aqueous solution for 30 seconds to remove the surface oxide film formed in step (2) above. (4) The static contact angle W0 of the above test piece (wafer before SC-1 processing) with deionized water is measured within 3 seconds after the deionized bath solution. (5) The test piece is immersed in deionized water and then cleaned with SC-1 cleaning solution for 10 seconds. The test piece is then immersed in deionized water and further immersed in 2.5% HF aqueous solution for 30 seconds to remove the surface oxide film. (6) The static contact angle W1 of the above test piece (wafer after SC-1 processing) with deionized water is measured within 3 seconds after the deionized bath solution. (7) From the W0 and W1 thus obtained, the desorption parameter is calculated by the following formula: W1 / W0×100.

[0047] In the above steps (1) and (5), the treatment with the SC-1 cleaning solution can be suitably carried out by placing the SC-1 cleaning solution, which is a mixture of 29% ammonia water, 31% hydrogen peroxide water, and deionized water in a volume ratio of 0.5:0.5:8, in a cleaning tank and immersing the test piece in this cleaning solution at room temperature. However, the above treatment conditions can be appropriately changed depending on the initial state of the test piece to be used, so that the static contact angles W0 and W1 can be appropriately measured.

[0048] In the above steps (4) and (6), the contact angle measuring device may be a contact angle meter such as DropMaster DMo-501 manufactured by Kyowa Interface Science Co., Ltd. or an equivalent product.

[0049] The surface of a clean silicon wafer is hydrophobic. Water-soluble polymers attached to the surface of a silicon wafer reduce the static contact angle with deionized water. For this reason, water-soluble polymers with a small W0 value are considered to protect the test piece surface well. On the other hand, water-soluble polymers with a large W1 value tend to be easily removed by cleaning treatment using an SC-1 cleaning solution (hereinafter referred to as SC-1 treatment). Therefore, the desorption parameter can be an indicator of the surface protection effect of the water-soluble polymer and the ease of removal of the water-soluble polymer by SC-1 treatment.

[0050] The reason why the effect of reducing the number of surface defects can be obtained by rinsing using a rinsing composition containing a water-soluble polymer A having a desorption parameter of 150 or more is not particularly limited, but it is believed that a water-soluble polymer with a high desorption parameter reduces the number of PIDs by protecting the surface of the object to be polished well during rinsing, and is easily removed together with the abrasive grains contained in the polishing composition in the SC-1 cleaning solution treatment, thereby reducing the number of abrasive grain residues. As a result, the above-mentioned rinsing composition can suitably achieve both a reduction in the number of PIDs and a reduction in the number of abrasive grain residues. By rinsing the object to be polished that has been polished with the polishing composition using such a rinsing composition containing the water-soluble polymer A, the number of defects of the object to be polished can be reduced. From this viewpoint, in some embodiments, the desorption parameter of the water-soluble polymer A may be, for example, 170 or more, 200 or more, or 300 or more.

[0051] The water-soluble polymer A is not particularly limited as long as it has a desorption parameter of 150 or more, and one or more of the known water-soluble polymers described above may be appropriately selected and used. In some embodiments, a nonionic polymer may be preferably used as the water-soluble polymer A, since it is easy to obtain a polymer having the preferred desorption parameter disclosed herein. For example, the water-soluble polymer A may be selected from the above-mentioned vinyl alcohol-based polymers, polymers containing oxyalkylene units, nitrogen atom-containing polymers, cellulose derivatives, starch derivatives, etc., which have an elimination parameter of 150 or more. In some embodiments, a nitrogen atom-containing polymer may be preferably selected as the water-soluble polymer A. Among them, a nitrogen atom-containing polymer containing an N-(meth)acryloyl type monomer unit, such as a linear or cyclic amide having an N-(meth)acryloyl group, is preferred.

[0052] The content (weight-based content) of the water-soluble polymer A in the rinse composition is not particularly limited. For example, -4 From the viewpoint of reducing the number of defects, the preferred content is 2.0×10 -4% by weight or more, more preferably 5.0×10 -4 % by weight or more, more preferably 1.0×10 -3 % by weight or more, e.g. 2.0×10 -3 % by weight or more. From the viewpoint of cleaning efficiency, the content is preferably 0.2% by weight or less, more preferably 0.1% by weight or less, and even more preferably 0.05% by weight or less (e.g., 0.02% by weight or less). When the rinsing composition contains two or more water-soluble polymers having a desorption parameter of 150 or more, the content of the water-soluble polymer A refers to the total content (content by weight) of all water-soluble polymers having a desorption parameter of 150 or more contained in the rinsing composition.

[0053] The weight average molecular weight (Mw) of the water-soluble polymer A is not particularly limited. From the viewpoint of easily obtaining the preferable desorption parameters disclosed herein, the Mw of the water-soluble polymer A is usually 200×10 4 Below, 150 x 10 4 or less, or 100 x 10 4 From the viewpoint of improving the cleaning property, in some embodiments, the Mw of the water-soluble polymer A is, for example, 50 × 10 4 may be less than or equal to 30 x 10 4 Less than 20×10 is fine. 4 Less than 10 x 10 is fine. 4 Less than 5×10 is fine. 4 Less than 3×10 is fine. 4 In order to easily obtain the effect of reducing the number of defects, the Mw of the water-soluble polymer A is usually 2000 or more, and may be 3000 or more, or may be 3500 or more. 4 or more or 2×10 4The present invention can also be carried out in an embodiment using the water-soluble polymer A. In this specification, the weight-average molecular weight of the water-soluble polymer and the surfactant described later can be a value based on aqueous gel permeation chromatography (GPC) (aqueous, polyethylene oxide equivalent) or a molecular weight calculated from a chemical formula. As a GPC measuring device, it is recommended to use a model named "HLC-8320GPC" manufactured by Tosoh Corporation. The measurement can be carried out, for example, under the following conditions. The same method is also used in the examples described later. [GPC measurement conditions] Sample concentration: 0.1% by weight Column: TSKgel GMPWXL Detector: Differential refractometer Eluent: 100mM sodium nitrate aqueous solution / acetonitrile = 10~8 / 0~2 Flow rate: 1mL / min Measurement temperature: 40℃ Sample injection volume: 200 μL

[0054] (Water-soluble polymer B) The rinsing composition disclosed herein may contain, as the water-soluble polymer, in addition to the water-soluble polymer A having a desorption parameter of 150 or more, a water-soluble polymer B having a desorption parameter of less than 150. A rinsing composition further containing the water-soluble polymer B in combination with the water-soluble polymer A is preferred from the viewpoint of surface protection of the object to be polished during rinsing, and is also preferred from the viewpoint of ease of removal by SC-1 treatment after rinsing, reduction in the number of abrasive grain residues, etc. From such a viewpoint, in some embodiments, the desorption parameter of the water-soluble polymer B may be, for example, less than 140, 130 or less, or 120 or less.

[0055] The water-soluble polymer B is not particularly limited as long as the desorption parameter is less than 150, and one or more of the above-mentioned known water-soluble polymers may be appropriately selected and used. In some embodiments, a nonionic polymer may be preferably used as the water-soluble polymer B. For example, the water-soluble polymer B may be selected from the above-mentioned vinyl alcohol-based polymers, polymers containing oxyalkylene units, nitrogen atom-containing polymers, cellulose derivatives, starch derivatives, etc., which have a detachment parameter of less than 150. In some embodiments, a vinyl alcohol-based polymer may be preferably used as the water-soluble polymer B. A preferred example of the rinsing composition disclosed herein is a rinsing composition that contains a nitrogen atom-containing polymer having a detachment parameter of 150 or more as the water-soluble polymer A, and further contains a vinyl alcohol-based polymer having a detachment parameter of less than 150 as the water-soluble polymer B.

[0056] When the rinse composition disclosed herein contains the water-soluble polymer B, the content of the water-soluble polymer B in the rinse composition (content by weight, when two or more kinds of water-soluble polymers B are contained, the total content thereof) is not particularly limited. For example, 1.0×10 -4 From the viewpoint of reducing the number of defects, the preferred content is 2.0×10 -4 % by weight or more, more preferably 5.0×10 -4 % by weight or more, more preferably 1.0×10 -3 % by weight or more, e.g. 2.0×10 -3 From the viewpoint of cleaning efficiency and the like, the content is preferably 0.2% by weight or less, more preferably 0.1% by weight or less, and even more preferably 0.05% by weight or less (for example, 0.02% by weight or less).

[0057] The content of the water-soluble polymer B in the total content of the water-soluble polymers contained in the rinse composition (when two or more kinds of water-soluble polymers B are contained, the total content of them) may be, for example, 25% by weight or more, preferably 40% by weight or more, 50% by weight or more, more than 50% by weight, 70% by weight or more, 80% by weight or more, or 95% by weight or more. In this specification, the total content of the water-soluble polymers refers to the total content (content by weight) of all the water-soluble polymers contained in the rinse composition.

[0058] The weight average molecular weight (Mw) of the water-soluble polymer B is not particularly limited. Usually, the Mw of the water-soluble polymer B is 200×10 4 Below, 150 x 10 4 or less, or 100 x 10 4 From the viewpoint of improving the cleaning property, in some embodiments, the Mw of the water-soluble polymer B is, for example, 50×10 or less. 4 may be less than or equal to 30 x 10 4 Less than 20×10 is fine. 4 Less than 10 x 10 is fine. 4 Less than 5×10 is fine. 4 Less than 3×10 is fine. 4 In order to facilitate the effect of reducing the number of defects on the polishing object after rinsing in combination with the water-soluble polymer A, the Mw of the water-soluble polymer B is usually 2000 or more, and may be 3000 or more, or 3500 or more. 4 or more or 2×10 4 The above-mentioned embodiment using the water-soluble polymer B can also be carried out.

[0059] <Basic compounds> The rinse composition disclosed herein may further contain a basic compound. In this specification, the basic compound refers to a compound that dissolves in water and has the function of increasing the pH of the aqueous solution. The basic compound may be used alone or in combination of two or more. Examples of the basic compound that can be used include organic or inorganic basic compounds containing nitrogen, basic compounds containing phosphorus, hydroxides of alkali metals, hydroxides of alkaline earth metals, various carbonates and hydrogen carbonates, etc. Examples of the basic compound containing nitrogen include quaternary ammonium compounds, ammonia, amines (preferably water-soluble amines), etc. Examples of the basic compound containing phosphorus include quaternary phosphonium compounds.

[0060] Specific examples of hydroxides of alkali metals include potassium hydroxide and sodium hydroxide. Specific examples of carbonates or hydrogen carbonates include ammonium hydrogen carbonate, ammonium carbonate, potassium hydrogen carbonate, potassium carbonate, sodium hydrogen carbonate, and sodium carbonate. Specific examples of amines include methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, monoethanolamine, N-(β-aminoethyl)ethanolamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, anhydrous piperazine, piperazine hexahydrate, 1-(2-aminoethyl)piperazine, N-methylpiperazine, guanidine, azoles such as imidazole and triazole, and the like. Specific examples of quaternary phosphonium compounds include quaternary phosphonium hydroxides such as tetramethylphosphonium hydroxide and tetraethylphosphonium hydroxide.

[0061] As the quaternary ammonium compound, a quaternary ammonium salt (typically a strong base) such as a tetraalkylammonium salt or a hydroxyalkyltrialkylammonium salt can be preferably used. The anion component in such a quaternary ammonium salt is, for example, OH - , F - , Cl - , Br - , I - , ClO4 - , BH4 - etc. In particular, a preferred example is one in which the anion is OH - Specific examples of quaternary ammonium hydroxides include tetraalkylammonium hydroxides such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrapentylammonium hydroxide, and tetrahexylammonium hydroxide; hydroxyalkyltrialkylammonium hydroxides such as 2-hydroxyethyltrimethylammonium hydroxide (also called choline); and the like.

[0062] Among these basic compounds, at least one basic compound selected from, for example, alkali metal hydroxides, quaternary ammonium hydroxides, and ammonia can be preferably used. Among these, potassium hydroxide, tetraalkylammonium hydroxide (e.g., tetramethylammonium hydroxide), and ammonia are more preferable, and ammonia is particularly preferable.

[0063] <Surfactant> The rinsing composition disclosed herein may contain a surfactant as necessary. By containing a surfactant in the rinsing composition, the number of defects on the surface of the polishing object after rinsing can be reduced more effectively. Any of anionic, cationic, nonionic, and amphoteric surfactants can be used as the surfactant. Usually, anionic or nonionic surfactants can be preferably used. From the viewpoint of low foaming and ease of pH adjustment, nonionic surfactants are more preferable. For example, nonionic surfactants include oxyalkylene polymers such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; polyoxyalkylene derivatives such as polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene alkylamines, polyoxyethylene fatty acid esters, polyoxyethylene glyceryl ether fatty acid esters, and polyoxyethylene sorbitan fatty acid esters (e.g., polyoxyalkylene adducts); and copolymers of multiple types of oxyalkylenes (e.g., diblock copolymers, triblock copolymers, random copolymers, and alternating copolymers). The above surfactants preferably include a surfactant containing a polyoxyalkylene structure. The surfactants can be used alone or in combination of two or more.

[0064] Specific examples of nonionic surfactants containing a polyoxyalkylene structure include block copolymers of ethylene oxide (EO) and propylene oxide (PO) (diblock copolymers, PEO (polyethylene oxide)-PPO (polypropylene oxide)-PEO type triblock copolymers, PPO-PEO-PPO type triblock copolymers, etc.), random copolymers of EO and PO, polyoxyethylene glycol, polyoxyethylene propyl ether, polyoxyethylene butyl ether, polyoxyethylene pentyl ether, polyoxyethylene hexyl ether, polyoxyethylene octyl ether, polyoxyethylene-2-ethylhexyl ether, polyoxyethylene nonyl ether, polyoxyethylene decyl ether, polyoxyethylene isodecyl ether, polyoxyethylene tridecyl ether, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene isostearyl ether, polyoxyethylene propylene glycol, polyoxyethylene propyl ether, polyoxyethylene butyl ether, polyoxyethylene pentyl ether, polyoxyethylene hexyl ether, polyoxyethylene octyl ether, polyoxyethylene 2-ethylhexyl ether, polyoxyethylene nonyl ether, polyoxyethylene decyl ether, polyoxyethylene isodecyl ether, polyoxyethylene tridecyl ether, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene isostearyl ether, polyoxyethylene propylene glycol ... Examples of the polyoxyethylene oleyl ether include polyoxyethylene phenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene styrenated phenyl ether, polyoxyethylene laurylamine, polyoxyethylene stearylamine, polyoxyethylene oleylamine, polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyethylene distearate, polyoxyethylene monooleate, polyoxyethylene dioleate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalminate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tetraoleate, polyoxyethylene castor oil, and polyoxyethylene hydrogenated castor oil.Among these, preferred surfactants include block copolymers of EO and PO (particularly, PEO-PPO-PEO type triblock copolymers), random copolymers of EO and PO, and polyoxyethylene alkyl ethers (for example, polyoxyethylene decyl ether).

[0065] The weight average molecular weight (Mw) of the surfactant is typically less than 2000, and is preferably 1900 or less (for example, less than 1800) from the viewpoint of cleaning properties. In addition, the Mw of the surfactant is usually appropriate to be 200 or more from the viewpoint of surface activity, and is preferably 250 or more (for example, 300 or more) from the viewpoint of the effect of reducing the number of defects. A more preferable range of the Mw of the surfactant may vary depending on the type of the surfactant. For example, when a polyoxyethylene alkyl ether is used as the surfactant, its Mw is preferably 1500 or less, and may be 1000 or less (for example, 500 or less). In addition, when a PEO-PPO-PEO type triblock copolymer is used as the surfactant, its Mw may be, for example, 500 or more, 1000 or more, or even 1200 or more.

[0066] When the rinse composition disclosed herein contains a surfactant, the content of the surfactant is not particularly limited as long as it is within a range that does not significantly impair the effects of the present invention. Generally, from the viewpoint of cleaning properties, the content of the surfactant in the rinse composition (content by weight) is, for example, 1.0×10 -5 From the viewpoint of reducing the number of defects, the preferred content is 2.0×10 -5 % by weight or more, more preferably 5.0×10 -5 % by weight or more, more preferably 1.0×10 -4 % by weight or more, e.g. 2.0×10 -4% by weight or more. From the viewpoint of cleaning efficiency, the content is preferably 0.02% by weight or less, more preferably 0.01% by weight or less, and even more preferably 0.005% by weight or less (e.g., 0.002% by weight or less). Alternatively, from the viewpoint of simplifying the composition, the rinsing composition disclosed herein may be preferably implemented in an embodiment that does not substantially contain a surfactant.

[0067] <Water> The rinse composition disclosed herein typically contains water. As the water, ion-exchanged water (deionized water), pure water, ultrapure water, distilled water, etc. can be preferably used. In order to avoid as much as possible the inhibition of the action of other components contained in the rinse composition, it is preferable that the water used has a total transition metal ion content of, for example, 100 ppb or less. For example, the purity of the water can be increased by removing impurity ions using an ion exchange resin, removing foreign matter using a filter, distillation, or other operations.

[0068] <Other ingredients> In addition, the rinse composition disclosed herein may further contain, as necessary, known additives such as a chelating agent, an organic acid, an organic acid salt, an inorganic acid, an inorganic acid salt, a preservative, or an antifungal agent, as long as the effects of the present invention are not significantly impaired.

[0069] The rinse composition disclosed herein is preferably substantially free of an oxidizing agent. Specific examples of the oxidizing agent referred to here include hydrogen peroxide (H2O2), sodium persulfate, ammonium persulfate, and sodium dichloroisocyanurate. The rinse composition being substantially free of an oxidizing agent means that the oxidizing agent is not intentionally contained at least. Therefore, a rinse composition that inevitably contains a small amount of oxidizing agent (for example, the molar concentration of the oxidizing agent in the rinse composition is 0.0005 mol / L or less, preferably 0.0001 mol / L or less, more preferably 0.00001 mol / L or less, and particularly preferably 0.000001 mol / L or less) due to raw materials, manufacturing method, etc., can be included in the concept of a rinse composition that does not substantially contain an oxidizing agent referred to here.

[0070] The rinse composition disclosed herein does not contain abrasive grains. The rinse composition does not contain abrasive grains means that the rinse composition does not contain abrasive grains at least intentionally. When the rinse composition that does not contain abrasive grains is used for rinsing, the number of abrasive grain residues after rinsing can be reduced.

[0071] <ph> The pH of the rinsing composition disclosed herein is typically 8.0 or more, preferably 8.5 or more, more preferably 9.0 or more. From the viewpoint of compatibility with the polishing composition used immediately before the rinsing step, the pH of the rinsing composition is usually appropriate to be 12.0 or less, preferably 11.0 or less, more preferably 10.8 or less, and even more preferably 10.5 or less.

[0072] The pH can be determined by using a pH meter (for example, a glass electrode type hydrogen ion concentration indicator (model number F-23) manufactured by HORIBA, Ltd.) and performing three-point calibration using standard buffer solutions (phthalate pH buffer solution, pH: 4.01 (25° C.), neutral phosphate pH buffer solution, pH: 6.86 (25° C.), carbonate pH buffer solution, pH: 10.01 (25° C.)), then placing the glass electrode in the composition to be measured and measuring the value after stabilization for at least two minutes.

[0073] <Rinse solution> The rinsing composition disclosed herein is typically supplied to the surface of the polished object after polishing in the form of a rinsing liquid containing the rinsing composition, and is used to rinse the polished object. The rinsing liquid may be prepared, for example, by diluting any of the rinsing compositions disclosed herein (typically diluting with water). Alternatively, the rinsing composition may be used as a rinsing liquid as it is. That is, the concept of the rinsing composition in the technology disclosed herein includes both a rinsing liquid that is supplied to the polished object after polishing and used to rinse the polished object, and a concentrated liquid (undiluted rinsing liquid) that is diluted and used as a rinsing liquid.

[0074] <Concentrate> The rinsing composition disclosed herein may be in a concentrated form (i.e., in the form of a concentrated rinsing liquid) before being supplied to a polishing object after polishing. A rinsing composition in such a concentrated form is advantageous from the viewpoints of convenience and cost reduction during production, distribution, storage, etc. The concentration ratio is not particularly limited, and can be, for example, about 2 to 100 times in volume conversion, and is usually about 5 to 50 times (for example, about 10 to 40 times). Such a concentrated solution can be used in such a manner that it is diluted at a desired time to prepare a rinse solution, and the rinse solution is supplied to the polishing object after polishing. The dilution can be performed, for example, by adding water to the concentrated solution and mixing it.

[0075] <Preparation of Rinse Composition> The rinse composition used in the technology disclosed herein may be a one-component type or a multi-component type such as a two-component type. For example, the rinse composition may be configured to prepare a polishing liquid by mixing a part A containing at least a water-soluble polymer A and a part B containing at least a part of the remaining components, and mixing and diluting them at an appropriate timing as necessary.

[0076] The method for preparing the rinse composition is not particularly limited. For example, the components constituting the rinse composition may be mixed using a well-known mixing device such as a blade stirrer, an ultrasonic disperser, or a homomixer. The manner in which these components are mixed is not particularly limited, and for example, all the components may be mixed at once, or may be mixed in an appropriately set order.

[0077] <Application> The rinsing composition disclosed herein can be applied to the rinsing of the polished object having various materials and shapes after polishing.The material of the polished object can be, for example, metal or semimetal such as silicon, aluminum, nickel, tungsten, copper, tantalum, titanium, stainless steel, or their alloys; glassy material such as quartz glass, aluminosilicate glass, glassy carbon; ceramic material such as alumina, silica, sapphire, silicon nitride, tantalum nitride, titanium carbide; compound semiconductor substrate material such as silicon carbide, gallium nitride, gallium arsenide; resin material such as polyimide resin; etc.The polished object can be made of a plurality of materials among these.

[0078] The rinsing composition disclosed herein can be particularly preferably used for rinsing after polishing a surface made of silicon (typically, polishing a silicon wafer). A typical example of the silicon wafer referred to here is a silicon single crystal wafer, for example, a silicon single crystal wafer obtained by slicing a silicon single crystal ingot.

[0079] The rinsing composition disclosed herein can be preferably applied to rinse an object to be polished (e.g., a silicon wafer) after a polishing step. The object to be polished may be subjected to a general treatment, such as lapping or etching, that can be applied to the object to be polished in a step upstream of the polishing step, before the polishing step.

[0080] The rinsing composition disclosed herein is effective for use in rinsing after polishing of a finishing step or a polishing step immediately preceding the finishing step of an object to be polished (e.g., a silicon wafer), and is particularly preferably used for rinsing after a finishing polishing step. Here, the finishing polishing step refers to the final polishing step in the manufacturing process of the object (i.e., a step after which no further polishing is performed).

[0081] <Rinse method> The rinsing composition disclosed herein can be used to rinse an object to be polished after polishing, for example, in an embodiment including the following operations. A preferred embodiment of a method for rinsing an object to be polished (e.g., a silicon wafer) after polishing with the rinsing composition disclosed herein is described below. That is, a rinse solution containing any of the rinse compositions disclosed herein is prepared. The preparation of the rinse solution may include adjusting the concentration (e.g., diluting) of the rinse composition, adjusting the pH, and the like to prepare the rinse solution. Alternatively, the rinse composition may be used as it is as the rinse solution.

[0082] Next, the rinse liquid is supplied to the polished object after polishing, and rinsed in a conventional manner. For example, when rinsing is performed after the finish polishing process of a silicon wafer, typically, the silicon wafer that has been subjected to the finish polishing process is attached to a general polishing device, or while still attached to the polishing device that performed the finish polishing process, the rinse liquid is supplied to the polishing surface of the silicon wafer through the pad of the polishing device. Typically, while continuously supplying the rinse liquid, the pad is pressed against the polishing surface of the silicon wafer, and the two are moved relatively (for example, rotated). Rinsing of the polishing object is completed through this rinsing process.

[0083] The pad used in the rinsing step is not particularly limited. For example, a pad of a foamed polyurethane type, a nonwoven fabric type, a suede type, or the like can be used. Each pad may or may not contain abrasive grains. Usually, a pad that does not contain abrasive grains is preferably used.

[0084] The rinsing using the rinsing composition disclosed herein can be performed immediately after the polishing process, on the polishing object that is still attached to the polishing device used in the polishing process, on the same platen as the polishing platen. Alternatively, after the polishing process, the polishing object can be removed from the polishing device and transferred to another platen for rinsing. From the viewpoint of work efficiency, etc., it is preferable to perform rinsing on the platen of the polishing device used in the polishing process.

[0085] The temperature at which the rinse composition disclosed herein is used is not particularly limited, but a temperature of 5 to 60°C is preferable.

[0086] The polishing object rinsed with the rinsing composition disclosed herein is typically cleaned. Cleaning can be performed using an appropriate cleaning liquid. The cleaning liquid used is not particularly limited, and for example, SC-1 cleaning liquid (a mixture of ammonium hydroxide (NH4OH), hydrogen peroxide (H2O2), and water (H2O)) and SC-2 cleaning liquid (a mixture of HCl, H2O2, and H2O) that are common in the field of semiconductors and the like can be used. The temperature of the cleaning liquid can be, for example, in the range of room temperature (typically about 15°C to 25°C) or higher, up to about 90°C. From the viewpoint of improving the cleaning effect, a cleaning liquid of about 50°C to 85°C can be preferably used. EXAMPLES

[0087] Some examples of the present invention will be described below, but it is not intended that the present invention be limited to those shown in these examples. In the following description, "parts" and "%" are by weight unless otherwise specified.

[0088] <Preparation of Rinse Composition> Example 1 A water-soluble polymer, a basic compound, a surfactant, and deionized water were mixed to prepare a rinse composition according to this example. As the water-soluble polymer, polyacryloylmorpholine (hereinafter referred to as "PACMO") with a desorption parameter of 174 and a weight average molecular weight of about 350,000 and polyvinyl alcohol (PVA) with a desorption parameter of 117, a weight average molecular weight of about 100,000, and a saponification degree of 97.5% or more were used. The content of PACMO was 0.004%. The content of PVA was 0.005%. Ammonia was used as the basic compound, and its content was 0.005%. As the surfactant, polyoxyethylene decyl ether with an ethylene oxide addition mole number of 5 (hereinafter referred to as "C10PEO5") was used, and its content was 0.0008%.

[0089] Example 2 A rinse composition according to this example was prepared in the same manner as in Example 1, except that the PACMO content was changed to 0.002% in the composition of Example 1.

[0090] Comparative Example 1 The rinse composition of this example was prepared in the same manner as in Example 1, except that hydroxyethyl cellulose (hereinafter referred to as "HEC") with a desorption parameter of 140 and a weight-average molecular weight of approximately 250,000 was used as the water-soluble polymer and its content was 0.013%.

[0091] Comparative Example 2 In this example, no rinsing with a rinsing composition was performed.

[0092] <Polishing, rinsing, and cleaning of silicon wafers> The polishing target was a commercially available silicon single crystal wafer with a diameter of 300 mm (conductivity type: P type, crystal orientation: <100> The sample (COP-free) was pre-polished under the following polishing condition 1. The pre-polishing was performed using a polishing solution containing 0.95% abrasive grains (colloidal silica with an average primary particle size of 35 nm) and 0.065% potassium hydroxide in deionized water.

[0093] [Polishing conditions 1] Polishing device: Single-wafer polishing device model "PNX-332B" manufactured by Okamoto Machine Tool Works, Ltd. Polishing load: 20kPa Rotation speed of the platen: 20 rpm Head (carrier) rotation speed: 20 rpm Polishing pad: Fujibo Ehime Co., Ltd. Product name "POLYPAS27NX" Supply rate of pre-polishing liquid: 1L / min Temperature of pre-polishing solution: 20℃ Plate cooling water temperature: 20℃ Polishing time: 2 minutes

[0094] The silicon wafer after the above pre-polishing was finish-polished under the following polishing condition 2. A polishing composition prepared by mixing abrasive grains, a water-soluble polymer, a basic compound, a surfactant, and deionized water was used as the polishing liquid. Colloidal silica (average primary particle size: 25 nm) was used as the abrasive grains, and its content was 0.18%. HEC with a weight-average molecular weight of about 250,000 and N-vinylpyrrolidone homopolymer (hereinafter referred to as "PVP") with a weight-average molecular weight of about 45,000 were used as the water-soluble polymers. The content of HEC was 0.004%. The content of PVP was 0.003%. Ammonia was used as the basic compound, and its content was 0.005%. C10PEO5 was used as the surfactant, and its content was 0.0002%.

[0095] [Polishing conditions 2] Polishing device: Single-wafer polishing device model "PNX-332B" manufactured by Okamoto Machine Tool Works, Ltd. Polishing load: 15kPa Rotation speed of the platen: 30 rpm Head (carrier) rotation speed: 30 rpm Polishing pad: Fujibo Ehime Co., Ltd. Product name "POLYPAS27NX" Polishing fluid supply rate: 2L / min Polishing solution temperature: 20℃ Plate cooling water temperature: 20℃ Polishing time: 2.5 minutes

[0096] The rinsing compositions according to the respective examples prepared above were used as rinsing liquids to rinse the silicon wafers after the above-mentioned finish polishing under the following rinsing conditions.

[0097] [Rinse conditions] Equipment: Single-wafer polishing machine manufactured by Okamoto Machine Tools Works, Ltd. Model "PNX-332B" Load: 5kPa Rotation speed of the platen: 30 rpm Head (carrier) rotation speed: 30 rpm Pad: Fujibo Ehime Co., Ltd. Product name "POLYPAS27NX" Rinse solution supply rate: 1L / min Rinse solution temperature: 20℃ Plate cooling water temperature: 20℃ Rinse time: 10 seconds

[0098] The rinsed silicon wafer was removed from the device and washed with a cleaning solution of NH4OH (29%):H2O2 (31%):deionized water (DIW) = 2:5.3:48 (volume ratio) (SC-1 cleaning). Specifically, a cleaning tank equipped with an ultrasonic oscillator was prepared, and the above cleaning solution was placed in the cleaning tank and maintained at 60°C. The polished silicon wafer was immersed in the cleaning tank for 6 minutes, and then rinsed with ultrapure water. This process was repeated twice, and the silicon wafer was then dried.

[0099] <Measurement of number of defects> After cleaning, the silicon wafer surface was inspected using a wafer inspection device manufactured by KLA Tencor, called "Surfscan SP2 XP " was used to detect surface defects. Each detected defect was analyzed using a defect review SEM (scanning electron microscope) manufactured by Hitachi High-Technologies Corporation, product name "Review-SEM RS6000," and the number of defects was counted as the number of abrasive residues and the number of PIDs. The number of abrasive residues and the number of PIDs in each example in which rinsing was performed were calculated relative to the number of abrasive residues and the number of PIDs in Comparative Example 1 in which rinsing was not performed, with the number of abrasive residues and the number of PIDs being set at 100, respectively. The results are shown in Table 1.

[0100] [Table 1]

[0101] As shown in Table 1, in Examples 1 and 2, in which the object to be polished was rinsed using a rinsing composition containing PACMO, which has a desorption parameter of 150 or more, as a water-soluble polymer, and non-modified PVA, which has a desorption parameter of less than 150, a clear reduction in the number of defects (i.e., the number of abrasive residues and the number of PIDs) on the surface of the object to be polished was confirmed compared to Comparative Example 1, in which rinsing was not performed after polishing. On the other hand, in Comparative Example 2, in which the object to be polished was rinsed using a rinsing composition containing only HEC, which has a desorption parameter of less than 150, as a water-soluble polymer, the number of abrasive residues on the surface of the object to be polished was reduced compared to Comparative Example 1, in which rinsing was not performed after polishing, but no reduction in PIDs was observed and instead increased.

[0102] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples exemplified above.< / ph>

Claims

1. A rinse composition comprising a water-soluble polymer and no abrasive grains, The water-soluble polymer may be a polymer having the following formula (I): W1 / W0×100 (I) (W0 in the formula (I) is the static contact angle of deionized water of a wafer before SC-1 cleaning treatment, which is obtained by applying an aqueous solution of a water-soluble polymer to be evaluated to the surface of a silicon wafer and then rinsing with water, and W1 in the formula (I) is the static contact angle of deionized water of a wafer after SC-1 treatment, which is obtained by performing a cleaning treatment for 10 seconds on the wafer before SC-1 cleaning treatment with a room temperature SC-1 cleaning solution containing 29% ammonia water, 31% hydrogen peroxide water, and water in a volume ratio of 0.5:0.5:8.) The water-soluble polymer A has a desorption parameter of 150 or more, The water-soluble polymer further includes a water-soluble polymer B having an elimination parameter represented by formula (I) of less than 150, The weight average molecular weight of the water-soluble polymer B is 2×10 ４ That's all. The rinse composition further comprises a surfactant.

2. The rinse composition according to claim 1 , wherein the water-soluble polymer A comprises a nitrogen atom-containing polymer.

3. The rinse composition according to claim 1 or 2, further comprising a basic compound.

4. A rinsing method for rinsing an object to be polished that has been polished in a polishing step using a polishing composition containing abrasive grains, comprising: A rinsing method comprising: a rinsing step of supplying a rinsing liquid containing the rinsing composition according to claim 1 to the object to be polished to rinse the object.

5. The rinsing method according to claim 4 , wherein in the rinsing step, the rinsing liquid is supplied to the object to be polished on a platen of a polishing apparatus used in the polishing step.

6. 6. The rinsing method according to claim 4, wherein the object to be polished is a silicon wafer.

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