Composition for forming protective film and semiconductor substrate manufacturing method

Abstract

Provided are a composition for forming a protective film and a semiconductor substrate manufacturing method. The composition and method are capable of, even when forming a thick protective film, achieving fine storage stability, coatability, crack resistance, weight loss suppressing properties, etching liquid resistance, and detachability. This composition for forming a protective film on a peripheral portion of a substrate contains a solvent and a polysiloxane having a first structural unit represented by formula (1). In the composition for forming a protective film, the content proportion of the polysiloxane with respect to components other than the solvent in the composition is not less than 50 mass%. (In formula (1), X represents a monovalent group having an aromatic ring that has 3-20 carbon atoms and that is substituted with a vinyl group or an ethynyl group. a represents an integer of 1-3. R1 represents a monovalent organic group having 1-20 carbon atoms, a hydroxy group, or a halogen atom. b represents an integer of 0-2. Here, a+b is 3 or less.)

Description

Composition for forming protective film and method for manufacturing semiconductor substrate

[0001] The present invention relates to a composition for forming a protective film and a method for producing a semiconductor substrate.

[0002] For pattern formation in the manufacture of semiconductor substrates, for example, a multilayer resist process is used in which a resist film laminated on a substrate via an organic underlayer film, a silicon-containing film, etc. is exposed and developed to obtain a resist pattern, which is then used as a mask to perform etching to form a patterned substrate.

[0003] When the beveled edge of the substrate is contaminated or damaged by repeated stacking processes, yields decrease. To address this issue, a technique for protecting the beveled edge has been proposed (see International Publication No. WO 2023 / 171733).

[0004] International Publication No. 2023 / 171733

[0005] Compositions for forming protective films on the peripheral edge of substrates are required to have storage stability and coatability, as well as crack resistance, weight loss suppression, etching solution resistance, and peelability for the resulting protective films.

[0006] An object of the present invention is to provide a composition for forming a protective film that exhibits good storage stability, coatability, crack resistance, weight loss suppression, etching solution resistance, and peelability, and a method for producing a semiconductor substrate.

[0007] As a result of extensive research into solving the above problems, the present inventors have found that the above object can be achieved by employing the following configuration, and have thus completed the present invention.

[0008] In one embodiment, the present invention relates to a composition for forming a protective film on a peripheral portion of a substrate, the composition comprising: a polysiloxane having a first structural unit represented by the following formula (1); and a solvent, wherein the content of the polysiloxane in the composition for forming a protective film other than the solvent is 50 mass% or more. (In the above formula (1), X is a monovalent group having an aromatic ring having 3 to 20 carbon atoms and substituted with a vinyl group or an ethynyl group. a is an integer of 1 to 3. When a is 2 or more, multiple Xs may be the same or different. R １ is a monovalent organic group having 1 to 20 carbon atoms, a hydroxy group, or a halogen atom. b is an integer of 0 to 2. When b is 2, two R １ are the same or different, provided that a + b is 3 or less.)

[0009] This protective film-forming composition exhibits excellent storage stability and coatability, even when forming a thick protective film, and can form a protective film that exhibits excellent crack resistance, weight loss suppression, etching solution resistance, and peelability at the peripheral edge of the substrate. While the reason for this is unclear, it is presumed as follows: During film formation, crosslinking of the vinyl group or ethynyl group introduced onto the aromatic ring in the first structural unit improves film strength. This crosslinking reaction primarily proceeds via a radical polymerization reaction that does not involve dehydration or other elimination components (hereinafter collectively referred to as "degassing components"). This allows film formation while maintaining film density and prevents film destruction due to the generation of degassing components from within the film. Furthermore, the introduction of an aromatic ring enhances hydrophobicity, improving the solubility of the polysiloxane in solvents and improving its durability to etching solutions. Meanwhile, the introduction of a relatively bulky aromatic ring can prevent the film from becoming excessively crosslinked. It is presumed that these synergistic effects enable the desired effects to be achieved.

[0010] In another embodiment, the present invention relates to a method for producing a semiconductor substrate, the method including a step of applying the protective film-forming composition directly or indirectly only to the peripheral edge portion of a substrate.

[0011] In this manufacturing method, the above-described composition for forming a protective film is used to form a protective film on the peripheral edge of the substrate, so that high-quality semiconductor substrates can be manufactured with a good yield.

[0012] As used herein, the term "periphery of the substrate" refers to the peripheral portion of the substrate that is within 3.0 cm of the outer periphery in the direction from the outer periphery toward the center of the substrate. The distance from the outer periphery toward the center of the substrate can be 2.0 cm, 1.0 cm, or 0.5 cm. "Polysiloxane" refers to a compound containing a siloxane bond (-Si-O-Si-). "Organic group" refers to a group containing at least one carbon atom, and "carbon number" refers to the number of carbon atoms constituting the group. "Hydrocarbon group" includes linear hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups. This "hydrocarbon group" may be saturated or unsaturated. "Linear hydrocarbon group" refers to a hydrocarbon group that does not contain a cyclic structure and is composed solely of a linear structure, and includes both linear and branched hydrocarbon groups. An "alicyclic hydrocarbon group" refers to a hydrocarbon group that contains only an alicyclic structure as a ring structure and does not contain an aromatic ring structure, and includes both monocyclic alicyclic hydrocarbon groups and polycyclic alicyclic hydrocarbon groups. However, it does not have to be composed solely of an alicyclic structure, and it may contain a chain structure as part of it. An "aromatic hydrocarbon group" refers to a hydrocarbon group that contains an aromatic ring structure as a ring structure. However, it does not have to be composed solely of an aromatic ring structure, and it may contain a chain structure or an alicyclic structure as part of it.

[0013] The protective film-forming composition and the method for producing a semiconductor substrate according to the embodiment of the present invention will be described in detail below.

[0014] <Composition for forming a protective film> The composition for forming a protective film according to this embodiment contains a polysiloxane and a solvent. The composition may contain other optional components (hereinafter also simply referred to as "optional components") within a range that does not impair the effects of the present invention.

[0015] This protective film-forming composition has good storage stability and coatability, and the protective film formed on the peripheral edge of the substrate has excellent crack resistance, weight loss suppression, etching solution resistance, and peelability, making it suitable for use in the production of semiconductor substrates, which are becoming increasingly highly integrated.

[0016] [Polysiloxane] The composition for forming a protective film contains a polysiloxane having a predetermined first structural unit. The composition for forming a protective film may contain one or more types of polysiloxane. The polysiloxane may have structural units other than the first structural unit (hereinafter simply referred to as "other structural units") within a range that does not impair the effects of the present invention. Each structural unit contained in the polysiloxane will be described below.

[0017] (First Structural Unit) The first structural unit is represented by the following formula (1): The polysiloxane may have one or more types of first structural units.

[0018] (In the above formula (1), X is a monovalent group having an aromatic ring having 3 to 20 carbon atoms and substituted with a vinyl group or an ethynyl group. a is an integer of 1 to 3. When a is 2 or more, multiple Xs may be the same or different. R １ is a monovalent organic group having 1 to 20 carbon atoms, a hydroxy group, or a halogen atom. b is an integer of 0 to 2. When b is 2, two R １ are the same or different, provided that a + b is 3 or less.)

[0019] As the monovalent group represented by X, a group in which one hydrogen atom has been removed from an aromatic ring having 3 to 20 carbon atoms and substituted with a vinyl group or an ethynyl group can be suitably used.

[0020] In the above formula (1), examples of the aromatic ring having 3 to 20 carbon atoms represented by X include aromatic hydrocarbon rings having 6 to 20 carbon atoms, such as a benzene ring, a naphthalene ring, an anthracene ring, a phenalene ring, a phenanthrene ring, a pyrene ring, a fluorene ring, and a perylene ring; aromatic heterocyclic rings having 3 to 20 carbon atoms, such as an imidazole ring, a furan ring, a pyrrole ring, a thiophene ring, a phosphole ring, a pyrazole ring, an oxazole ring, an isoxazole ring, a thiazole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, a triazine ring, and a carbazole ring; and combinations thereof. The combination of these rings may be a fused ring, a ring assembly (a structure in which two rings are bonded by a single bond), or a spiro structure. The aromatic ring is preferably an aromatic hydrocarbon ring having 6 to 20 carbon atoms, and more preferably a benzene ring.

[0021] The number of vinyl or ethynyl groups on the aromatic ring is not particularly limited, but is preferably 1, 2 or 3, more preferably 1 or 2, and even more preferably 1.

[0022] The crosslinkable group on the aromatic ring is preferably a vinyl group.

[0023] R １ Examples of the monovalent organic group having 1 to 20 carbon atoms and represented by the formula (I) include a monovalent hydrocarbon group having 1 to 20 carbon atoms, a group containing a divalent heteroatom-containing linking group between the carbon-carbon bond of this hydrocarbon group (hereinafter also referred to as "group (α)"), a group in which some or all of the hydrogen atoms in the hydrocarbon group or the group (α) have been substituted with monovalent heteroatom-containing substituents (hereinafter also referred to as "group (β)"), and a group in which the hydrocarbon group, the group (α) or the group (β) is combined with a divalent heteroatom-containing linking group (hereinafter also referred to as "group (γ)").

[0024] Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms include a monovalent chain hydrocarbon group having 1 to 20 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms, and combinations thereof.

[0025] Examples of the monovalent chain hydrocarbon group having 1 to 20 carbon atoms include alkyl groups such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, and a tert-butyl group; alkenyl groups such as an ethenyl group, a propenyl group, and a butenyl group; and alkynyl groups such as an ethynyl group, a propynyl group, and a butynyl group.

[0026] Examples of the monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms include monocyclic alicyclic saturated hydrocarbon groups such as a cyclopentyl group and a cyclohexyl group; polycyclic alicyclic saturated hydrocarbon groups such as a norbornyl group, an adamantyl group, a tricyclodecyl group and a tetracyclododecyl group; monocyclic alicyclic unsaturated hydrocarbon groups such as a cyclopentenyl group and a cyclohexenyl group; and polycyclic alicyclic unsaturated hydrocarbon groups such as a norbornenyl group, a tricyclodecenyl group and a tetracyclododecenyl group.

[0027] As the monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms, a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring having 6 to 20 carbon atoms in X of the above formula (1) can be suitably used.

[0028] Examples of heteroatoms constituting the divalent heteroatom-containing linking group and the monovalent heteroatom-containing substituent include an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, a halogen atom, etc. Examples of halogen atoms include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0029] Examples of the divalent heteroatom-containing linking group include -O-, -C(=O)-, -S-, -C(=S)-, -NR'-, and -SO ２ -, a group consisting of two or more of these, etc. R' is a hydrogen atom or a monovalent hydrocarbon group.

[0030] Examples of the monovalent hetero atom-containing substituent include a halogen atom, a hydroxy group, a carboxy group, a cyano group, an amino group, and a sulfanyl group.

[0031] R １ is preferably a monovalent chain hydrocarbon group, a monovalent aromatic hydrocarbon group or a hydroxy group, more preferably an alkyl group, an aryl group or a hydroxy group, and even more preferably a methyl group, an ethyl group, a phenyl group or a hydroxy group.

[0032] a is preferably 1 or 2, and more preferably 1.

[0033] b is preferably 0 or 1.

[0034] Examples of compounds that provide the first structural unit include compounds represented by the following formulas (1-1) to (1-12).

[0035] (In the formula, R １ａ is a methyl group or an ethyl group.

[0036] The lower limit of the content of the first structural unit (total when multiple types are present) in all structural units constituting the polysiloxane is preferably 5 mol%, more preferably 10 mol%, and even more preferably 15 mol%. The upper limit of the content of the first structural unit is preferably 40 mol%, more preferably 30 mol%, and even more preferably 25 mol%. By having the content of the first structural unit within the above range, the storage stability, coatability, crack resistance, weight loss suppression, etching solution resistance, and peelability of the protective film-forming composition can be improved.

[0037] (Second structural unit) The polysiloxane preferably has a second structural unit (excluding the first structural unit) represented by the following formula (2) as a structural unit other than the first structural unit. The polysiloxane can have one or more types of second structural units. When the polysiloxane has the second structural unit, the crack resistance of the formed protective film can be further improved, along with the coatability of the protective film-forming composition.

[0038] (In the above formula (2), R ２１ and R ２２ are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms.

[0039] R ２１ and R ２２ The monovalent hydrocarbon group having 1 to 10 carbon atoms represented by the formula (1) is R １ Among the monovalent hydrocarbon groups having 1 to 20 carbon atoms shown in the above, structures corresponding to those having 1 to 10 carbon atoms can be suitably employed.

[0040] R ２１ and R ２２ When the polysiloxane has one type of second structural unit, it is preferable that one of the second structural units is a monovalent chain hydrocarbon group having 1 to 10 carbon atoms and the other is a monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms. ２１ and R ２２ When the polysiloxane has two types of second structural units, two R ２１ and two R ２２Of the total four groups, it is preferred that at least one group is a monovalent chain hydrocarbon group having 1 to 10 carbon atoms, and at least one group is a monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms. ２１ and two R ２２ As combinations of a total of four groups, a combination of one monovalent chain hydrocarbon group having 1 to 10 carbon atoms and three monovalent aromatic hydrocarbon groups having 6 to 10 carbon atoms, a combination of two monovalent chain hydrocarbon groups having 1 to 10 carbon atoms and two monovalent aromatic hydrocarbon groups having 6 to 10 carbon atoms, and a combination of three monovalent chain hydrocarbon groups having 1 to 10 carbon atoms and one monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms are preferred.

[0041] R ２１ and R ２２ In the formula (1), the monovalent chain hydrocarbon group having 1 to 10 carbon atoms is R １ Among the monovalent chain hydrocarbon groups having 1 to 20 carbon atoms shown in the above, structures corresponding to carbon atoms having 1 to 10 can be suitably employed. Among them, as the monovalent chain hydrocarbon group having 1 to 10 carbon atoms, alkyl groups having 1 to 5 carbon atoms and alkenyl groups having 2 to 5 carbon atoms are preferred, and methyl groups and ethenyl groups (vinyl groups) are more preferred.

[0042] R ２１ and R ２２ The monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms in the formula (1) is R １ Among these, the monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group.

[0043] R ２１ and R ２２When has a substituent, examples of the substituent include halogen atoms such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom; alkoxy groups such as a methoxy group, an ethoxy group, and a propoxy group; alkoxycarbonyl groups such as a methoxycarbonyl group and an ethoxycarbonyl group; alkoxycarbonyloxy groups such as a methoxycarbonyloxy group and an ethoxycarbonyloxy group; acyl groups such as a formyl group, an acetyl group, a propionyl group, and a butyryl group; acyloxy groups such as a formyloxy group, an acetyloxy group, a propionyloxy group, and a butyryloxy group; a hydroxy group, a cyano group, a nitro group, an amino group, a sulfanyl group, and a carboxy group.

[0044] Examples of compounds that provide the second structural unit include compounds represented by the following formulae (2-1a) to (2-1d), (2-2a) to (2-2d), and (2-3a) to (2-3d). When the polysiloxane has one type of second structural unit, any of the compounds represented by the following formulae (2-1a) to (2-1d) is preferred. When the polysiloxane has two types of second structural units, a combination of one selected from the compounds represented by the following formulae (2-1a) to (2-1d) and (2-2a) to (2-2d) and one selected from the compounds represented by the following formulae (2-3a) to (2-3d) is preferred.

[0045] (In the formula, R ２ａ is a methyl group or an ethyl group.

[0046] The second structural unit represented by the above formula (2) (excluding the first structural unit) may be a structural unit represented by the following formula (2A). (In the above formula (2A), R ２１ and R ２２ has the same meaning as in formula (2) above. n is an integer of 2 to 200.

[0047] In the formula (2A), the lower limit of n is preferably 3. In the formula (2A), the upper limit of n is preferably 200, and more preferably 100.

[0048] The lower limit of the average sequence number of the structural units represented by the formula (2) in the structural unit represented by the formula (2A) is preferably 5, and more preferably 10. The upper limit of the average sequence number of the structural units represented by the formula (2) in the structural unit represented by the formula (2A) is preferably 200, more preferably 100, and even more preferably 50.

[0049] Examples of compounds that provide the structural unit represented by formula (2A) include disilanol compounds (intermediate oligomers) obtained by ring-opening condensation of compounds represented by formulas (2A-1) to (2A-5) with water. Commercially available disilanol compounds can be used. Examples of commercially available disilanol compounds that can be used include FM-9915, FM-9925A (manufactured by JNC Corporation), PMX-0156, PMX-0930 (manufactured by Dow-Toray Industries, Inc.), X-21-5841, KF-9701, X-21-5847, and X-21-5849 (manufactured by Shin-Etsu Chemical Co., Ltd.), and XC96-723, YF3800, XF3905, YF3057, YF3807, YF3802, and YF3897 (manufactured by Momentive Performance Materials Japan, LLC).

[0050]

[0051] When the polysiloxane contains the second structural unit, the lower limit of the content of the second structural unit (total when multiple types are present) in all structural units constituting the polysiloxane is preferably 10 mol%, more preferably 15 mol%, and even more preferably 20 mol%, and the upper limit of the content of the second structural unit is preferably 70 mol%, more preferably 60 mol%, and even more preferably 55 mol%.

[0052] (Third Structural Unit) The polysiloxane may have a third structural unit (excluding the first structural unit and the second structural unit) represented by the following formula (3) as a structural unit other than the first structural unit. By having the third structural unit, it is possible to appropriately control the liquid quality of the protective film-forming composition and the film quality of the protective film.

[0053] (In the above formula (3), R ３１is a monovalent organic group having 1 to 20 carbon atoms, a hydroxy group, or a halogen atom. c is an integer of 0 to 3. When c is 2 or more, multiple R ３１ are the same or different.)

[0054] R ３１ The monovalent organic group having 1 to 20 carbon atoms represented by the formula (1) is R １ A monovalent organic group having 1 to 20 carbon atoms and represented by the following formula can be suitably used. ３１ R is preferably a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms. As the monovalent aromatic hydrocarbon group, a phenyl group, a naphthyl group, or a biphenyl group is preferred. ３１ When R has a substituent, the substituent may be R ２１ and R ２２ The substituents that may be possessed by the group can be suitably employed.

[0055] Examples of compounds that provide the third structural unit include compounds represented by the following formulas (3-1) to (3-26).

[0056]

[0057] (In the formula, R ３ａ is a methyl group or an ethyl group.

[0058] When polysiloxane has third structural unit, the lower limit of the content ratio of the third structural unit (when there are multiple types, the total) in the total structural units that constitute polysiloxane is preferably 1 mol%, more preferably 15 mol%, and even more preferably 30 mol%.In addition, the upper limit of the content ratio is preferably 85 mol%, more preferably 80 mol%, and even more preferably 75 mol%.By making the content ratio of the third structural unit within the above range, it can form a silicon-containing film that has better anti-reflection performance.

[0059] The content of the polysiloxane in the protective film-forming composition (total content when multiple types are present) relative to the components other than the solvent is 50% by mass or more. The lower limit of the content is preferably 60% by mass, more preferably 70% by mass, and even more preferably 80% by mass. The upper limit of the content may be 100% by mass, 99% by mass, or 98% by mass.

[0060] The polysiloxane is preferably in the form of a polymer. In this specification, the term "polymer" refers to a compound having two or more structural units, and when two or more identical structural units are consecutive in a polymer, this structural unit is also referred to as a "repeating unit." When the polysiloxane is in the form of a polymer, the lower limit of the polystyrene-equivalent weight average molecular weight (Mw) of the polysiloxane measured by gel permeation chromatography (GPC) is preferably 500, more preferably 1,500, and even more preferably 2,000. The upper limit of the Mw is preferably 30,000, more preferably 15,000, and even more preferably 10,000. The method for measuring the Mw of the polysiloxane is as described in the Examples.

[0061] The lower limit of the silanol group (Si—OH group) content in the polysiloxane is preferably 1 mol%, more preferably 3 mol%, and even more preferably 5 mol%. The upper limit of the content is preferably 100 mol%, more preferably 60 mol%, and even more preferably 30 mol%. The method for measuring the silanol group content in the polysiloxane is as described in the Examples. For example, when it is necessary to form a thick film of 1 to 5 μm, in order to improve crack resistance, the lower limit of the silanol group content is preferably 1 mol%. The upper limit of the content is preferably 100 mol%, more preferably 30 mol%. In processes requiring resistance to etching solutions such as tetramethylammonium hydroxide (TMAH) aqueous solutions, the lower limit of the silanol group content is preferably 50 mol%, more preferably 80 mol%. The upper limit of the content is preferably 200 mol%, more preferably 120 mol%.

[0062] [Method of Synthesizing Polysiloxane] Polysiloxane can be synthesized by a conventional method using monomers that provide each structural unit. For example, a monomer that provides the first structural unit and, if necessary, monomers that provide other structural units can be hydrolyzed and condensed in a solvent in the presence of a catalyst such as oxalic acid and water, and the solution containing the resulting hydrolysis and condensation product can then be purified by solvent substitution or the like in the presence of a dehydrating agent such as trimethyl orthoformate. It is believed that each monomer is incorporated into the polysiloxane regardless of its type through the hydrolysis and condensation reaction or the like. Therefore, the content ratio of the first structural unit and other structural units in the synthesized polysiloxane is usually substantially the same as the ratio of the amounts of each monomer used in the synthesis reaction.

[0063] [Solvent] The solvent is not particularly limited, and examples thereof include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, nitrogen-containing solvents, hydrocarbon-based solvents, water, etc. The protective film-forming composition may contain one or more solvents.

[0064] Examples of alcohol solvents include monoalcohol solvents such as methanol, ethanol, n-propanol, isopropanol, n-butanol, and isobutanol, and polyalcohol solvents such as ethylene glycol, 1,2-propylene glycol, diethylene glycol, and dipropylene glycol.

[0065] Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl isobutyl ketone, and cyclohexanone.

[0066] Examples of ether solvents include ethyl ether, isopropyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, and tetrahydrofuran.

[0067] Examples of ester solvents include ethyl acetate, γ-butyrolactone, n-butyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, ethyl propionate, n-butyl propionate, methyl lactate, and ethyl lactate.

[0068] Examples of nitrogen-containing solvents include N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

[0069] Examples of hydrocarbon solvents include aliphatic hydrocarbon solvents having 5 to 12 carbon atoms, such as n-pentane and n-hexane; and aromatic hydrocarbon solvents having 6 to 16 carbon atoms, such as toluene and xylene.

[0070] Among these, ether-based solvents or ester-based solvents are preferred, and ether-based solvents or ester-based solvents having a glycol structure are more preferred due to their excellent film-forming properties, and ester-based solvents having a glycol structure are even more preferred.

[0071] Examples of ether solvents and ester solvents having a glycol structure include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, etc. Among these, propylene glycol monomethyl ether acetate is more preferred.

[0072] The lower limit of the content of the solvent in the composition for forming a protective film is preferably 5 mass %, more preferably 8 mass %, and even more preferably 10 mass %, based on all components contained in the composition for forming a protective film, and the upper limit of the content is preferably 80 mass %, more preferably 70 mass %, and even more preferably 65 mass %.

[0073] The viscosity of the protective film-forming composition at 25°C is not particularly limited and may be set appropriately depending on the desired thickness of the protective film, the location where the protective film is to be formed, etc. The lower limit of the viscosity is preferably 1 mPa·s, more preferably 5 mPa·s, and even more preferably 10 mPa·s. The upper limit of the viscosity is preferably 1000 mPa·s, more preferably 300 mPa·s, and even more preferably 200 mPa·s. The method for measuring the viscosity of the protective film-forming composition at 25°C is as described in the Examples.

[0074] (Optional Components) Examples of optional components include photoacid generators, basic compounds (including base generators), acid diffusion controllers, radical generators, polymerizable compounds (crosslinking agents), surfactants, colloidal silica, colloidal alumina, organic polymers, etc. The protective film-forming composition can contain one or more optional components.

[0075] When the composition for forming a protective film contains an optional component, the content ratio of the optional component in the composition for forming a protective film can be appropriately determined depending on the type of optional component used and within a range that does not impair the effects of the present invention.

[0076] <Method for preparing the composition for forming a protective film> The method for preparing the composition for forming a protective film is not particularly limited, and the composition can be prepared according to a conventional method. For example, the composition can be prepared by mixing a polysiloxane solution, a solvent, and, if necessary, optional components in a predetermined ratio, and preferably filtering the resulting mixed solution through a filter having a pore size of 0.4 μm or less.

[0077] <Method for manufacturing semiconductor substrate> In the present embodiment, a typical method for manufacturing a semiconductor substrate includes a step of forming a silicon-containing film directly or indirectly on a substrate (hereinafter also referred to as a "silicon-containing film-forming step"), a step of applying a resist film-forming composition directly or indirectly to the silicon-containing film to form a resist film (hereinafter also referred to as a "resist film-forming step"), a step of exposing the resist film to radiation (hereinafter also referred to as an "exposure step"), and a step of developing the exposed resist film to form a resist pattern (hereinafter also referred to as a "development step").

[0078] The method for producing a semiconductor substrate may further include, as necessary, a step of forming an organic underlayer film directly or indirectly on the substrate (hereinafter also referred to as an "organic underlayer film forming step") prior to the silicon-containing film forming step.

[0079] Furthermore, after the developing step, the method may further include a step of etching the silicon-containing film using the resist pattern as a mask to form a silicon-containing film pattern (hereinafter also referred to as a "silicon-containing film pattern forming step"); a step of etching using the silicon-containing film pattern as a mask (hereinafter referred to as an "etching step"); and a step of removing the silicon-containing film pattern with a basic liquid (hereinafter referred to as a "removing step").

[0080] The method for manufacturing a semiconductor substrate according to this embodiment includes a step of applying a protective film-forming composition directly or indirectly only to the peripheral edge of the substrate at any stage before or after each of the above steps (hereinafter also referred to as a "coating step"). In the coating step, the above-mentioned protective film-forming composition is used as the protective film-forming composition.

[0081] Hereinafter, each step included in the semiconductor substrate manufacturing method will be described, including an organic underlayer film forming step prior to the silicon-containing film forming step, and a silicon-containing film pattern forming step, etching step, and removal step after the development step.

[0082] [Organic Underlayer Film Formation Step] In this step, an organic underlayer film is formed directly or indirectly on a substrate prior to the silicon-containing film formation step. This step is an optional step. By this step, an organic underlayer film is formed directly or indirectly on a substrate.

[0083] Examples of the substrate include insulating films such as silicon oxide, silicon nitride, silicon oxynitride, and polysiloxane, and resin substrates. The substrate may also be a substrate patterned with a wiring groove (trenches), plug grooves (vias), or the like. The substrate may also be a wafer bonded body formed by stacking multiple wafers (see International Publication No. 2012 / 054577 for reference). The protective film-forming composition also makes it possible to form a protective film on the peripheral portion of the wafer bonded body (including the bonded portion and outer peripheral surface of the wafer bonded body) (see, for example, International Publication No. 2012 / 054577).

[0084] The organic underlayer film can be formed by coating an organic underlayer film-forming composition, etc. Examples of methods for forming an organic underlayer film by coating an organic underlayer film-forming composition include a method in which the organic underlayer film-forming composition is directly or indirectly applied to a substrate, and the resulting coating film is heated or exposed to light to cure it. Examples of the organic underlayer film-forming composition that can be used include "HM8006" manufactured by JSR Corporation. The heating and exposure conditions can be appropriately determined depending on the type of organic underlayer film-forming composition used, etc.

[0085] An example of a case where an organic underlayer film is formed indirectly on a substrate is a case where an organic underlayer film is formed on a low dielectric insulating film formed on a substrate.

[0086] [Silicon-containing film forming process] In this process, a silicon-containing film is formed directly or indirectly on a substrate.When the silicon-containing film forming composition is indirectly applied to a substrate, for example, the silicon-containing film forming composition is applied on another film formed on a substrate.When the other film formed on a substrate, for example, the organic underlayer film formed by the above-mentioned organic underlayer film forming process, an anti-reflection film, a low dielectric insulating film, etc. can be included.

[0087] The silicon-containing film can be formed by coating a silicon-containing film-forming composition, chemical vapor deposition (CVD), atomic layer deposition (ALD), or the like. Examples of methods for forming a silicon-containing film by coating a silicon-containing film-forming composition include a method in which the silicon-containing film-forming composition is directly or indirectly coated onto an organic underlayer film, and the resulting coating film is cured by exposure and / or heating. Examples of commercially available silicon-containing film-forming compositions include "NFC SOG01," "NFC SOG04," and "NFC SOG080" (all from JSR Corporation). Silicon oxide films, silicon nitride films, silicon oxynitride films, and amorphous silicon films can be formed by chemical vapor deposition (CVD) or atomic layer deposition (ALD).

[0088] Examples of radiation used for the exposure include electromagnetic waves such as visible light, ultraviolet light, far ultraviolet light, X-rays and gamma rays, and particle beams such as electron beams, molecular beams and ion beams.

[0089] When the coating film is heated, the atmosphere is not particularly limited, and examples thereof include air and nitrogen atmospheres. Typically, the coating film is heated in air. When the coating film is heated, the heating temperature, heating time, and other conditions can be appropriately determined. The lower limit of the heating temperature is preferably 90°C, more preferably 150°C, and even more preferably 200°C. The upper limit of the heating temperature is preferably 550°C, more preferably 450°C, and even more preferably 300°C. The lower limit of the heating time is preferably 15 seconds, and more preferably 30 seconds. The upper limit of the heating time is preferably 1,200 seconds, and more preferably 600 seconds.

[0090] When the silicon-containing film-forming composition contains an acid generator, and this acid generator is a radiation-sensitive acid generator, the formation of the silicon-containing film can be promoted by combining heating and exposure. Examples of the radiation used for exposure include the same radiation as exemplified in the exposure step described below.

[0091] The lower limit of the average thickness of the silicon-containing film is preferably 1 nm, more preferably 10 nm, and even more preferably 20 nm. The upper limit of the average thickness is preferably 20,000 nm, more preferably 1,000 nm, and even more preferably 100 nm. The method for measuring the average thickness of the silicon-containing film is the same as the method for measuring the average thickness of the protective film.

[0092] [Resist Film Forming Step] In this step, a resist film is formed by applying a resist film-forming composition directly or indirectly to the silicon-containing film. By this step, a resist film is formed directly or indirectly on the silicon-containing film.

[0093] The method for applying the resist film-forming composition is not particularly limited, and examples thereof include a rotary coating method.

[0094] To explain this step in more detail, for example, a resist composition is applied so that the resist film to be formed has a predetermined thickness, and then the applied resist film is pre-baked (hereinafter also referred to as "PB") to volatilize the solvent in the applied film, thereby forming the resist film.

[0095] The PB temperature and PB time can be appropriately determined depending on the type of the resist film-forming composition used, etc. The lower limit of the PB temperature is preferably 30°C, more preferably 50°C. The upper limit of the PB temperature is preferably 200°C, more preferably 150°C. The lower limit of the PB time is preferably 10 seconds, more preferably 30 seconds. The upper limit of the PB time is preferably 600 seconds, more preferably 300 seconds.

[0096] Examples of the resist composition include positive or negative chemically amplified resist compositions that contain a radiation-sensitive acid generator, positive resist compositions that contain an alkali-soluble resin and a quinone diazide-based photosensitizer, negative resist compositions that contain an alkali-soluble resin and a crosslinking agent, and metal-containing resist compositions that contain a metal such as tin, zirconium, or hafnium.

[0097] [Exposure Step] In this step, the resist film formed in the resist film-forming composition application step is exposed to radiation. This step generates a difference in solubility in an alkaline solution, which is a developer, between the exposed and unexposed areas of the resist film. More specifically, the solubility of the exposed areas of the resist film in an alkaline solution is increased.

[0098] The radiation used for exposure can be appropriately selected depending on the type of the resist film-forming composition used, etc. Examples include visible light, ultraviolet light, far ultraviolet light, electromagnetic waves such as X-rays and gamma rays, and particle beams such as electron beams, molecular beams, and ion beams. Among these, far ultraviolet light is preferred, and KrF excimer laser light (wavelength 248 nm), ArF excimer laser light (wavelength 193 nm), F ２ Excimer laser light (wavelength 157 nm), Kr ２ Excimer laser light (wavelength 147 nm), ArKr excimer laser light (wavelength 134 nm), or extreme ultraviolet light (wavelength 13.5 nm, etc., also referred to as "EUV") is more preferred, and ArF excimer laser light or EUV is even more preferred. The exposure conditions can be appropriately determined depending on the type of resist film-forming composition used, etc.

[0099] Furthermore, in this process, after the exposure, post-exposure baking (hereinafter also referred to as "PEB") can be performed to improve the performance of the resist film, such as resolution, pattern profile, and developability. The PEB temperature and PEB time can be appropriately determined depending on the type of resist film-forming composition used, etc. The lower limit of the PEB temperature is preferably 50°C, more preferably 70°C. The upper limit of the PEB temperature is preferably 200°C, more preferably 150°C. The lower limit of the PEB time is preferably 10 seconds, more preferably 30 seconds. The upper limit of the PEB time is preferably 600 seconds, more preferably 300 seconds.

[0100] [Development Step] In this step, the exposed resist film is developed. The development of the exposed resist film is preferably alkaline development. The exposure step causes a difference in solubility in an alkaline solution, which is a developer, between the exposed and unexposed portions of the resist film. Therefore, alkaline development removes the exposed portions, which have a relatively high solubility in an alkaline solution, thereby forming a resist pattern.

[0101] The developer used in alkaline development is not particularly limited, and known developers can be used. Examples of developers for alkaline development include alkaline aqueous solutions containing at least one alkaline compound such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, ethyldimethylamine, triethanolamine, tetramethylammonium hydroxide (TMAH), pyrrole, piperidine, choline, 1,8-diazabicyclo-[5.4.0]-7-undecene, and 1,5-diazabicyclo-[4.3.0]-5-nonene. Among these, a TMAH aqueous solution is preferred, and a 2.38 mass % TMAH aqueous solution is more preferred.

[0102] In addition, examples of the developer when organic solvent development is performed include the same solvents as those exemplified as the solvents in the above-mentioned composition for forming a protective film.

[0103] In this step, washing and / or drying may be carried out after the development.

[0104] [Silicon-containing Film Pattern Forming Step] In this step, the silicon-containing film is etched using the resist pattern as a mask to form a silicon-containing film pattern.

[0105] The etching may be either dry etching or wet etching, but dry etching is preferred.

[0106] Dry etching can be performed using, for example, a known dry etching apparatus. The etching gas used for dry etching can be appropriately selected depending on the elemental composition of the silicon-containing film to be etched, and for example, CHF ３ , C.F. ４ , C ２ F ６ , C ３ F ８ , SF ６ Fluorine-based gases such as Cl ２ , BCl ３ Chlorine gases such as O ２ , O ３ , H ２ Oxygen-based gases such as O, H ２ , CO, CO ２ , C.H. ４ , C ２ H ２ , C ２ H ４ , C ２ H ６ , C ３ H ４ , C ３ H ６ , C ３ H ８ , HF, HI, HBr, HCl, NO, NH ３ reducing gases such as He, N ２ Inert gases such as Ar and the like are used. These gases can also be used in combination. For dry etching of silicon-containing films, fluorine-based gases are usually used, and a mixture of fluorine-based gases with oxygen-based gases and inert gases is preferably used.

[0107] [Etching Step] In this step, etching is performed using the silicon-containing film pattern as a mask. More specifically, etching is performed one or more times using the pattern formed on the silicon-containing film obtained in the silicon-containing film pattern forming step as a mask to obtain a patterned substrate.

[0108] When an organic underlayer film is formed on a substrate, a pattern of the organic underlayer film is formed by etching the organic underlayer film using the silicon-containing film pattern as a mask, and then a pattern is formed on the substrate by etching the substrate using this organic underlayer film pattern as a mask.

[0109] The etching may be either dry etching or wet etching, but dry etching is preferred.

[0110] Dry etching for forming a pattern on the organic underlayer film can be performed using a known dry etching apparatus. The etching gas used for dry etching can be appropriately selected depending on the elemental composition of the silicon-containing film and the organic underlayer film to be etched. The etching gas can be suitably selected from the gases used for etching the silicon-containing film described above, and these gases can also be used in combination. An oxygen-based gas is usually used for dry etching the organic underlayer film using the silicon-containing film pattern as a mask.

[0111] Dry etching when forming a pattern on a substrate using an organic underlayer film pattern as a mask can be carried out using a known dry etching apparatus. The etching gas used in dry etching can be appropriately selected depending on the elemental composition of the organic underlayer film and the substrate to be etched, and examples thereof include the same etching gases as those exemplified as the etching gases used in dry etching of the organic underlayer film. Etching may be carried out multiple times using different etching gases. Note that, if a silicon-containing film remains on the substrate, the resist underlayer pattern, or the like after the substrate pattern formation step, the silicon-containing film can be removed by carrying out the removal step described below.

[0112] [Removal Step] In this step, the silicon-containing film pattern is removed with a basic liquid. This step removes the silicon-containing film from the substrate. Furthermore, residual silicon-containing film remaining after etching can be removed.

[0113] The basic liquid is not particularly limited as long as it is a basic solution containing a basic compound. Examples of basic compounds include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide (hereinafter also referred to as "TMAH"), tetraethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo[5.4.0]-7-undecene, and 1,5-diazabicyclo[4.3.0]-5-nonene. Among these, ammonia is preferred from the viewpoint of avoiding damage to the substrate.

[0114] From the viewpoint of further improving the removability of the silicon-containing film, the basic liquid is preferably a liquid containing a basic compound and water, or a liquid containing a basic compound, hydrogen peroxide, and water.

[0115] The method for removing the silicon-containing film is not particularly limited as long as it is a method that can bring the silicon-containing film into contact with a basic liquid, and examples thereof include a method of immersing a substrate in a basic liquid, a method of spraying a basic liquid, and a method of coating a basic liquid.

[0116] The conditions for removing the silicon-containing film, such as temperature and time, are not particularly limited and can be appropriately determined depending on the film thickness of the silicon-containing film, the type of basic solution used, etc. The lower limit of the temperature is preferably 20°C, more preferably 40°C, and even more preferably 50°C. The upper limit of the temperature is preferably 300°C, more preferably 100°C. The lower limit of the time is preferably 5 seconds, more preferably 30 seconds. The upper limit of the time is preferably 10 minutes, more preferably 180 seconds.

[0117] In this step, after removing the silicon-containing film, washing and / or drying may be carried out.

[0118] [Coating process of protective film-forming composition] In this process, which is carried out at any stage before or after the above process, the protective film-forming composition is directly or indirectly coated only on the peripheral edge of the substrate. Examples of indirectly coating the protective film-forming composition only on the peripheral edge of the substrate include forming a protective film on an organic underlayer film or silicon-containing film formed on the substrate. Note that the protective film-forming composition is preferably used to form the peripheral edge of the substrate, but may also be used to form a planarizing film on a semiconductor pattern by coating the entire substrate.

[0119] The method for applying the protective film-forming composition is not particularly limited, and known methods such as a rotary coating method (spin coating method) or a spray method can be used. For example, when a rotary coating method is used, the semiconductor substrate is rotated at a predetermined rotation speed, and the protective film-forming composition is supplied through a nozzle from above or near the front end of the rotating disk-shaped substrate. Preferably, the composition is also supplied through a nozzle from near the bevel portion and / or the back end of the substrate.

[0120] The conditions for spin coating can be selected appropriately and are not limited in any way, but typical conditions are as follows: Viscosity of the composition for forming a protective film: 10 mPa·s or more and 300 mPa·s or less Wafer rotation speed: When supplying the composition for forming a protective film: 50 rpm or more and 500 rpm or less When shaking off the dried film: 700 rpm or more and 2,000 rpm or less Protective film thickness: 300 nm or more and 5,000 nm (5 μm) or less

[0121] The coating film of the protective film-forming composition may be exposed to light. The exposure may be carried out by irradiating the protective film-forming composition with actinic light such as ultraviolet light, visible light, or radiation (including i-line, KrF excimer laser, ArF excimer laser, EUV (extreme ultraviolet)), or EB (electron beam)) through or without a mask. Soft baking (SB) may be carried out before exposure, or post-exposure baking (PEB) may be carried out after exposure and before development. The post-exposure baking temperature is preferably 50°C to 150°C, and the post-exposure baking time is preferably 1 minute to 10 minutes.

[0122] The lower limit of the average thickness of the protective film is preferably 100 nm, more preferably 200 nm, and even more preferably 300 nm.The upper limit of the average thickness of the protective film is preferably 1000 μm, more preferably 600 μm, and even more preferably 400 μm.

[0123] The protective film is preferably removed by ashing or cleaning. Cleaning is performed using a hydrofluoric acid solution or the like. Thereafter, cleaning is preferably performed using any solvent or a conventional semiconductor cleaning solution.

[0124] The present invention will be specifically described below based on examples, but the present invention is not limited to these examples.

[0125] [Measurement of Weight-Average Molecular Weight (Mw)] The weight-average molecular weight (Mw) of the polysiloxane was measured by gel permeation chromatography (GPC) using Tosoh Corporation's GPC columns (two "G2000HXL", one "G3000HXL", and one "G4000HXL") under the following conditions: (Measurement Conditions) Eluent: tetrahydrofuran Flow rate: 1.0 mL / min Sample concentration: 1.0 mass% Sample injection amount: 100 μL Column temperature: 40°C Detector: differential refractometer Standard material: monodisperse polystyrene

[0126] [Concentration of Polysiloxane in Solution] 0.5 g of the polysiloxane solution was baked at 250°C for 30 minutes, and the mass of the residue obtained was measured. The mass of this residue was divided by the mass of the polysiloxane solution to calculate the concentration of the polysiloxane solution (unit: mass%).

[0127] [Measurement of the content of silanol groups in polysiloxane] A polysiloxane solution containing 1 g of polysiloxane solution, 1 g of deuterated benzene as a heavy solvent, and 0.01 g of chromium (III) acetylacetonate as a relaxation reagent was placed in a 10 mm NMR tube. ２９ Si-NMR was measured, and the integrated values ​​of the constituent units D1, D2, T1, T2, T3, Q1, Q2, Q3, and Q4 were substituted into the following calculation formula (1) from the obtained chart to calculate the total number of moles N of silanol groups and alkoxy groups.

[0128] In this case, when two types of monomers were used for the D component or the T component, and the peaks were complex and it was difficult to distinguish between the components, the total number of moles N of silanol groups and alkoxy groups was calculated from the amounts used during synthesis, the integral values ​​of the signals at both ends of the D component, the T component, and the Q component, and a value estimated from the amounts used.

[0129] Next, 0.05 g of the polysiloxane solution and 0.8 g of deuterated chloroform as a heavy solvent were added to the polysiloxane solution, and the solution was placed in a 5 mm NMR tube. １ H-NMR was measured. The amount of alkoxy groups was calculated from the obtained chart by determining the ratio of the integrated value of the alkoxy groups to the substituent component of the polysiloxane, the amount of which was clearly defined, and the amount of silanol groups (mol %) was calculated by subtracting the amount of alkoxy groups from the value calculated by the above formula (1).

[0130] [Measurement of the average number of intermediate sequences (number of units) in the intermediate oligomer] A polysiloxane solution containing 1 g of the intermediate oligomer (disilanol compound) solution, 1 g of deuterated benzene as a heavy solvent, and 0.01 g of chromium (III) acetylacetonate as a relaxation reagent was placed in a 10 mm NMR tube. ２９ Si-NMR was measured. From the obtained chart, the integral value of the D2 component was calculated when the integral value of the D1 component was set to 2, and the average number of intermediate sequences (number) in the intermediate oligomer was calculated by adding the integral values ​​of the D1 component and the D2 component.

[0131] [Viscosity of Protective Film-Forming Composition] 1.2 ml of the polysiloxane solution was weighed out, and the viscosity was measured at 25° C. and 100 rpm using an E-type viscometer (manufactured by Toki Sangyo Co., Ltd., "RE-85").

[0132] [Average thickness of protective film] The average thickness of the protective film is a value obtained by discharging the protective film-forming composition onto the center of the substrate, forming a film from the protective film-forming composition over the entire substrate by a rotary coating method, measuring the film thickness at nine arbitrary positions at 5 cm intervals, including the center of the substrate, using a spectroscopic ellipsometer ("M2000D" manufactured by J.A. WOOLLAM Co., Ltd.), and calculating the average value of these film thicknesses.

[0133] <Synthesis of Polysiloxane> The monomers (hereinafter also referred to as "monomers (M-1) to (M-28)") and catalysts used in the synthesis in Synthesis Examples 1 to 44 and Comparative Synthesis Example 1 are shown below. In each of the following Synthesis Examples, mol % refers to the value for each monomer when the total number of moles of the monomers (M-1) to (M-28) used is taken as 100 mol %.

[0134]

[0135]

[0136] [C] Catalyst C-1: diazabicycloundecene C-2: trifluoromethanesulfonic acid C-3: oxalic acid C-4: phosphoric acid

[0137] [Synthesis Example 1] Synthesis of polysiloxane (A-1) In a reaction vessel, 28.0 parts by mass of compound (M-1), 11.5 parts by mass of compound (M-6), and 11.7 parts by mass of compound (M-22) were dissolved in 4.7 parts by mass of cyclopentyl methyl ether and 26.7 parts by mass of methylcyclohexane so that the ratio of the compounds was M-1 / M-6 / M-22 = 40 / 20 / 40 (mol%) to prepare a monomer solution. Next, the reaction vessel was heated to 35 ° C., and a solution prepared by dissolving 0.21 parts by mass of diazabicycloundecene (C-1) in 14.0 parts by mass of water and 3.1 parts by mass of methanol was added dropwise over 30 minutes. Thereafter, the vessel was heated to 60 ° C. and the reaction was carried out for 4 hours. After completion of the reaction, 0.09 parts by mass of acetic acid was added to the reaction vessel, and the vessel was cooled to below 30 ° C. Next, 25.0 parts by mass of cyclopentyl methyl ether and 75.1 parts by mass of methylcyclohexane were added to the cooled reaction solution, and the mixture was washed several times with water until the pH of the wash water reached 7.0. Next, 58.3 parts by mass of propylene glycol monomethyl ether acetate was added, and the water, cyclopentyl methyl ether, methylcyclohexane, and alcohols produced by the reaction were removed using an evaporator to obtain a propylene glycol monoethyl ether acetate solution with a polysiloxane (A-1) concentration of 60% by mass. The Mw, silanol content (mol%), and viscosity of the resulting polysiloxane are shown in Table 1-1 below.

[0138] Synthesis Examples 2 to 31 and 34 to 35: Synthesis of polysiloxanes (A-2) to (A-31) and (A-34) to (A-35) Propylene glycol monomethyl ether solutions of polysiloxanes (A-2) to (A-31) and (A-34) to (A-35) were obtained in the same manner as in Synthesis Example 1, except that the types and amounts of each monomer shown in Table 1 below were used. A "-" next to a monomer in Table 1 below indicates that the corresponding monomer was not used. The Mw, silanol content (mol %), and viscosity of the resulting polysiloxanes are also shown in Table 1-1 below.

[0139] [Synthesis Example 32] Synthesis of polysiloxane (A-32) In a reaction vessel equipped with a Dimroth condenser and a Dean-Stark tube, 20.2 g of compound (M-1), 20.6 g of compound (M-4), and 49.2 g of compound (M-8) were dissolved in 106 parts by mass of a mixed solution of methylcyclohexane / cyclopentyl methyl ether = 85 / 15 in a mass ratio so that the above compounds were M-1 / M-4 / M-8 = 20 / 25 / 55 (mol%) to prepare a monomer solution. Next, the inside of the Dean-Stark tube containing the monomer solution was filled with an additional mixed solution of methylcyclohexane / cyclopentyl methyl ether = 85 / 15 in a mass ratio, and further, a solution prepared by previously mixing 0.04 parts by mass of trifluoromethanesulfonic acid (C-2) and 13.4 parts by mass of water was added to the reaction vessel over 30 minutes with stirring, and the temperature was raised to 60 ° C., and the reaction was carried out for 1 hour. Next, the reaction was continued while removing methanol and water using a Dean-Stark tube until the temperature inside the reaction vessel reached 100°C. After completion of the reaction, the reaction vessel was cooled to below 30°C and washed with water several times until the pH of the wash water reached 7.0. Next, 90.0 parts by mass of propylene glycol monomethyl ether acetate was added, and the water, cyclopentyl methyl ether, methylcyclohexane, and alcohols produced during the reaction were removed using an evaporator to obtain a propylene glycol monoethyl ether acetate solution with a polysiloxane (A-32) concentration of 40% by mass. The Mw, silanol content (mol%), and viscosity of the obtained polysiloxane are also shown in Table 1-1 below.

[0140] [Synthesis Example 33] Synthesis of polysiloxane (A-33) In a reaction vessel equipped with a Dimroth condenser and a Dean-Stark tube, 18.4 g of compound (M-1), 37.3 g of compound (M-4), and 24.3 g of compound (M-8) were dissolved in 109 parts by mass of a mixed solution of methylcyclohexane / cyclopentyl methyl ether = 85 / 15 in a mass ratio such that the above compounds were M-1 / M-4 / M-8 = 20 / 50 / 30 (mol%) to prepare a monomer solution. Next, the inside of the Dean-Stark tube containing the monomer solution was filled with an additional mixed solution of methylcyclohexane / cyclopentyl methyl ether = 85 / 15 in a mass ratio, and a solution prepared in advance by mixing 0.04 parts by mass of trifluoromethanesulfonic acid (C-2) and 12.4 parts by mass of water was added to the reaction vessel over 30 minutes with stirring, and the temperature was raised to 60 ° C., and the reaction was carried out for 1 hour. Next, the reaction was continued while removing methanol and water using a Dean-Stark tube until the temperature inside the reaction vessel reached 100°C. After completion of the reaction, the reaction vessel was cooled to below 30°C and washed with water several times until the pH of the wash water reached 7.0. Next, 90.0 parts by mass of propylene glycol monomethyl ether acetate was added, and the water, cyclopentyl methyl ether, methylcyclohexane, and alcohols produced during the reaction were removed using an evaporator to obtain a propylene glycol monoethyl ether acetate solution with a polysiloxane (A-33) concentration of 40% by mass. The Mw, silanol content (mol%), and viscosity of the obtained polysiloxane are also shown in Table 1-1 below.

[0141] [Synthesis Example 36] Synthesis of polysiloxane (A-36) In a reaction vessel, 20.1 parts by mass of compound (M-1) and 20.47 parts by mass of compound (M-24) were dissolved in 41.3 parts by mass of propylene glycol monomethyl ether so that the molar ratio of the compounds was M-1 / M-24 = 40 / 60 (mol%) to prepare a monomer solution. Next, the reaction vessel was heated to 35 ° C., and a solution prepared by dissolving 1.45 parts by mass of oxalic acid (C-3) in 5.8 parts by mass of water and 10.9 parts by mass of propylene glycol monomethyl ether was added dropwise over 30 minutes while stirring. Thereafter, the vessel was heated to 60 ° C. and reacted for 4 hours. After completion of the reaction, 30.5 parts by mass of water was added to the reaction vessel, and the temperature was raised to 60 ° C. and the mixture was aged for 2 hours. The mixture was then cooled to below 30°C, and 95.6 parts by mass of propylene glycol monomethyl ether was added. Using an evaporator, water, alcohols produced by the reaction, and excess propylene glycol monomethyl ether were removed so that the polysiloxane concentration became 60% by mass, yielding a propylene glycol monomethyl ether solution of polysiloxane (A-36). The Mw, silanol content (mol %), and viscosity of the resulting polysiloxane are also shown in Table 1-1 below.

[0142] Synthesis Example 37 Synthesis of Polysiloxane (A-37) A propylene glycol monomethyl ether solution of polysiloxane (A-37) was obtained in the same manner as in Synthesis Example 36, except for using the types and amounts of each monomer shown in Table 1. The Mw, silanol content (mol %), and viscosity of the obtained polysiloxane are also shown in Table 1-1.

[0143] [Synthesis Example 38] Synthesis of polysiloxane (A-38) In a reaction vessel equipped with a Dimroth condenser and a Dean-Stark tube, 49.9 parts by mass of compound (M-1) and 40.1 parts by mass of compound (M24) were dissolved in 113 parts by mass of a mixed solution of methylcyclohexane / cyclopentyl methyl ether = 85 / 15 in a mass ratio such that the above compounds were M-1 / M-24 = 40 / 60 (mol%) to prepare a monomer solution. Next, the inside of the Dean-Stark tube containing the monomer solution was filled with an additional mixed solution of methylcyclohexane / cyclopentyl methyl ether = 85 / 15 in a mass ratio, and a solution prepared in advance by mixing 0.04 parts by mass of trifluoromethanesulfonic acid (C-2) and 19.8 parts by mass of water was added to the reaction vessel over 30 minutes with stirring, and the temperature was raised to 60 ° C., followed by a reaction for 1 hour. Next, the reaction was continued while removing methanol and water using a Dean-Stark tube until the temperature inside the reaction vessel reached 100°C. After completion of the reaction, the reaction vessel was cooled to below 30°C and washed with water several times until the pH of the wash water reached 7.0. Next, 90.0 parts by mass of propylene glycol monomethyl ether acetate was added, and water, cyclopentyl methyl ether, methylcyclohexane, and alcohols produced during the reaction were removed using an evaporator to obtain a propylene glycol monoethyl ether acetate solution with a solids concentration of polysiloxane (A-38) of 40% by mass. The Mw, silanol content (mol%), and viscosity of the obtained polysiloxane are also shown in Table 1-1 below.

[0144] [Synthesis Example 39] Synthesis of polysiloxane (A-39) In a reaction vessel, 13.84 parts by mass of the compound (M-25) was dissolved in 11.89 parts by mass of propylene glycol dimethyl ether to prepare a monomer solution. Next, the reaction vessel was heated to 35°C, and a solution prepared by dissolving 0.95 parts by mass of diazabicycloundecene (C-1) in 0.11 parts by mass of water and 3.96 parts by mass of propylene glycol dimethyl ether was added dropwise over 30 minutes. Thereafter, the vessel was heated to 40°C, and the reaction was carried out for 3 hours to obtain an intermediate oligomer.

[0145] Next, a solution of 11.18 parts by mass of the compound (M-1) and 27.12 parts by mass of the compound (M-8) dissolved in 0.34 parts by mass of cyclopentyl methyl ether and 1.96 parts by mass of methylcyclohexane was added dropwise to the reaction vessel over 30 minutes. The reaction was then carried out for 2 hours. Next, 2.38 parts by mass of cyclopentyl methyl ether and 13.48 parts by mass of methylcyclohexane were added, followed by the dropwise addition of 12.43 parts by mass of water over 30 minutes. The vessel was then heated to 60°C and the reaction was carried out for 3 hours. After the reaction was completed, 0.37 parts by mass of acetic acid was added to the reaction vessel and the vessel was cooled to below 30°C. Next, 25.0 parts by mass of cyclopentyl methyl ether and 75.0 parts by mass of methylcyclohexane were added to the cooled reaction solution, and the mixture was washed several times with water until the pH of the wash water reached 7.0. Next, 65.8 parts by mass of propylene glycol monomethyl ether acetate was added, and the water, cyclopentyl methyl ether, methylcyclohexane, propylene glycol dimethyl ether, and alcohols produced by the reaction were removed using an evaporator to obtain a propylene glycol monoethyl ether acetate solution with a polysiloxane (A-39) concentration of 60% by mass. The reaction concentration (mass%) during the synthesis of the intermediate in the intermediate oligomer, the average intermediate sequence number (units) in the intermediate oligomer, and the Mw, silanol content (mol%), and viscosity of the obtained polysiloxane are also shown in Table 1-2 below.

[0146] Synthesis Examples 40 to 42: Synthesis of polysiloxanes (A-40) to (A-42) Propylene glycol monomethyl ether acetate solutions of polysiloxanes (A-40) to (A-42) were obtained in the same manner as in Synthesis Example 39, except that the types and amounts of each monomer shown in Table 1-2 below were used. A "-" next to a monomer in Table 1-2 below indicates that the corresponding monomer was not used. The reaction concentration (mass %) during intermediate synthesis in the intermediate oligomer, the average intermediate sequence number (units) in the intermediate oligomer, and the Mw, silanol content (mol %), and viscosity of the resulting polysiloxane are also shown in Table 1-2 below.

[0147] [Synthesis Example 43] Synthesis of polysiloxane (A-43) In a reaction vessel, 13.84 parts by mass of the compound (M-25) was dissolved in 14.77 parts by mass of propylene glycol dimethyl ether to prepare a monomer solution. Next, the reaction vessel was heated to 35°C, and a solution prepared by dissolving 0.95 parts by mass of diazabicycloundecene (C-1) in 0.11 parts by mass of water and 4.92 parts by mass of propylene glycol dimethyl ether was added dropwise over 30 minutes. Thereafter, the vessel was heated to 40°C, and the reaction was carried out for 3 hours to obtain an intermediate oligomer.

[0148] Next, a solution of 11.18 parts by mass of the compound (M-1) and 27.12 parts by mass of the compound (M-8) dissolved in 0.84 parts by mass of cyclopentyl methyl ether and 4.75 parts by mass of methylcyclohexane was added dropwise to the reaction vessel over 30 minutes. The reaction was then carried out for 2 hours. Next, 1.31 parts by mass of cyclopentyl methyl ether and 7.41 parts by mass of methylcyclohexane were added, followed by the dropwise addition of 12.43 parts by mass of water over 30 minutes. The vessel was then heated to 60°C and the reaction was carried out for 3 hours. After the reaction was completed, 0.37 parts by mass of acetic acid was added to the reaction vessel, and the vessel was cooled to below 30°C. Next, 25.0 parts by mass of cyclopentyl methyl ether and 75.0 parts by mass of methylcyclohexane were added to the cooled reaction solution, and the mixture was washed several times with water until the pH of the wash water reached 7.0. Next, 65.4 parts by mass of propylene glycol monomethyl ether acetate was added, and the water, cyclopentyl methyl ether, methylcyclohexane, propylene glycol dimethyl ether, and alcohols produced by the reaction were removed using an evaporator to obtain a propylene glycol monoethyl ether acetate solution with a polysiloxane (A-43) concentration of 60% by mass. The reaction concentration (mass%) during the synthesis of the intermediate in the intermediate oligomer, the average number of intermediate sequences (units) in the intermediate oligomer, and the Mw, silanol content (mol%), and viscosity of the obtained polysiloxane are also shown in Table 1-2 below.

[0149] [Synthesis Example 44] Synthesis of polysiloxane (A-44) In a reaction vessel, 13.84 parts by mass of the compound (M-25) was dissolved in 9.58 parts by mass of propylene glycol dimethyl ether to prepare a monomer solution. Next, the reaction vessel was heated to 35°C, and a solution prepared by dissolving 0.95 parts by mass of diazabicycloundecene (C-1) in 0.11 parts by mass of water and 3.19 parts by mass of propylene glycol dimethyl ether was added dropwise over 30 minutes. Thereafter, the vessel was heated to 40°C, and the reaction was carried out for 3 hours to obtain an intermediate oligomer.

[0150] Next, a solution of 11.18 parts by mass of the compound (M-1) and 27.12 parts by mass of the compound (M-8) dissolved in 0.61 parts by mass of cyclopentyl methyl ether and 4.57 parts by mass of methylcyclohexane was added dropwise to the reaction vessel over 30 minutes. The reaction was then carried out for 2 hours. Next, 2.38 parts by mass of cyclopentyl methyl ether and 13.48 parts by mass of methylcyclohexane were added, followed by the dropwise addition of 12.43 parts by mass of water over 30 minutes. The vessel was then heated to 60°C and the reaction was carried out for 3 hours. After the reaction was completed, 0.37 parts by mass of acetic acid was added to the reaction vessel and the vessel was cooled to below 30°C. Next, 25.0 parts by mass of cyclopentyl methyl ether and 75.0 parts by mass of methylcyclohexane were added to the cooled reaction solution, and the mixture was washed several times with water until the pH of the wash water reached 7.0. Next, 65.4 parts by mass of propylene glycol monomethyl ether acetate was added, and water, cyclopentyl methyl ether, methylcyclohexane, propylene glycol dimethyl ether, and alcohols produced by the reaction were removed using an evaporator to obtain a propylene glycol monoethyl ether acetate solution with a polysiloxane (A-44) concentration of 60% by mass. The reaction concentration (mass%) during intermediate synthesis in the intermediate oligomer, the average intermediate sequence number (units) in the intermediate oligomer, and the Mw, silanol content (mol%), and viscosity of the obtained polysiloxane are also shown in Table 1-2 below.

[0151] Comparative Synthesis Example 1 Synthesis of Polysiloxane (a-1) In a reaction vessel, 55.1 parts by mass of compound (M-8) and 63.5 parts by mass of compound (M-24) were dissolved in 64.6 parts by mass of propylene glycol monomethyl ether so that the molar ratio of the compounds was M-8 / M-24 = 40 / 60 (mol%) to prepare a monomer solution. Next, a mixture of 45.1 parts by mass of water and 8.0 parts by mass of phosphoric acid (C-4) was added to the reaction vessel at room temperature while stirring over 30 minutes. Thereafter, the flask was immersed in a 70 ° C. oil bath and stirred for 1 hour, after which the oil bath was heated to 110 ° C. over 30 minutes. One hour after the start of the temperature increase, the internal temperature of the solution reached 100 ° C., and the mixture was heated and stirred for 2 hours. During the reaction, a total of 102 g of by-products, methanol and water, was distilled off, and then propylene glycol monomethyl ether was added until the solids concentration reached 40% by mass, yielding a propylene glycol monomethyl ether solution of polysiloxane (a-1). The Mw, silanol content (mol %), and viscosity of the resulting polysiloxane are also shown in Table 1-1 below.

[0152]

[0153]

[0154] <Preparation of Composition for Forming Protective Film (1)> The solvents and radical generators used in preparing the composition for forming a protective film are shown below. In the following Examples 1-1 to 1-43 and Comparative Example 1-1, unless otherwise specified, parts by mass indicate values ​​when the total mass of the components used is 100 parts by mass.

[0155] [B] Solvent B-1: Propylene glycol monomethyl ether acetate

[0156] [F] Radical generator F-1: a compound represented by the following formula (F-1):

[0157] [Example 1-1] Preparation of protective film-forming composition (J1-1) 85.9 parts by mass of (A-1) as polysiloxane and 14.1 parts by mass of (B-1) as solvent (including the solvent contained in the polysiloxane solution) were mixed, and the resulting solution was filtered through a polytetrafluoroethylene filter with a pore size of 0.2 μm to prepare protective film-forming composition (J1-1).

[0158] [Examples 1-2 to 1-43 and Comparative Example 1-1] Preparation of protective film-forming compositions (J1-2) to (J1-43), (j1-1) Compositions for forming protective films (J1-2) to (J1-43) of Examples 1-2 to 1-43 and composition for forming a protective film (j1-1) of Comparative Example 1-1 were prepared in the same manner as in Example 1, except that the types and amounts of each component shown in Table 2 below were used.

[0159] <Evaluation> The compositions prepared above were evaluated for storage stability, crack resistance, weight loss suppression, and coatability by the following methods. The evaluation results are shown in Table 2 below.

[0160]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0059]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083] [00

[0161] [Crack Resistance] When the obtained substrate with a protective film was heated at 400°C for 1 hour in a nitrogen atmosphere, if no cracks were found in the protective film, the rating was "A" (very good); when the obtained substrate with a protective film was heated at 400°C for 1 hour in a nitrogen atmosphere, if cracks were found in the protective film and the obtained substrate with a protective film was heated at 380°C for 1 hour in a nitrogen atmosphere, if no cracks were found in the protective film, the rating was "B" (very good); when the obtained substrate with a protective film was heated at 380°C for 1 hour in a nitrogen atmosphere, if cracks were found in the protective film and the obtained substrate with a protective film was When the substrate with the protective film obtained was heated at 350°C for 1 hour in a nitrogen atmosphere, if there were no cracks in the protective film, it was rated as "C" (good); when the substrate with the protective film obtained above was heated at 350°C for 1 hour in a nitrogen atmosphere, if there were cracks in the protective film and when the substrate with the protective film obtained above was heated at 300°C for 1 hour in a nitrogen atmosphere, if there were no cracks in the protective film, it was rated as "D" (fairly good); and when the substrate with the protective film obtained above was heated at 300°C for 1 hour in a nitrogen atmosphere, if there were cracks in the protective film, it was rated as "E" (poor).

[0162] [Storage Stability] The protective film-forming compositions were stored at 25°C for 7 days, and the weight average molecular weight (Mw) of each composition was evaluated. ０ Mw after 7 days storage ７ The rate of change in Mw was calculated using the following formula, and a rate of change of less than 5% was evaluated as "A (very good)", a rate of change in Mw after 7 days of storage from the Mw on the start of storage of 5% to less than 10% was evaluated as "B (good)", and a rate of change in Mw after 7 days of storage from the Mw on the start of storage of 10% or more was evaluated as "C (poor)". Rate of change in Mw (%) = {|Mw ７ -Mw ０ | / Mw ０} x 100

[0163] [Weight Loss Inhibition] The obtained substrate with a protective film was scraped to recover powder. The recovered powder was placed in a container for measurement using a TG-DTA device (NETZSCH's "TG-DTA2000SR"), and the mass before heating was measured. Next, using the TG-DTA device, the sample was heated to 400°C at a heating rate of 10°C / min under a nitrogen atmosphere, and the mass of the powder at 400°C was measured. The mass loss rate (%) was then measured using the following formula, and this mass loss rate was used as a measure of weight loss inhibition: ML = {(m1 - m2) / m1} x 100. In the formula, ML is the mass loss rate (%), m1 is the mass (mg) before heating, and m2 is the mass (mg) at 400°C. The smaller the mass loss rate of the sample powder, the less sublimate and film decomposition products are generated during film heating, and the better the weight loss inhibition. The weight loss suppression was evaluated as "A" (very good) when the mass loss rate was less than 1%, "B" (good) when it was 1% or more but less than 3%, "C" (fairly good) when it was 3% or more but less than 6%, and "D" (poor) when it was 6% or more.

[0164] [Coatability] A silicon wafer was rotated at 1,500 rpm using a spin coater ("CLEAN TRACK ACT8" manufactured by Tokyo Electron Limited). The protective film-forming composition prepared above was ejected from a position 1 cm from the outer periphery of the substrate to the center of the substrate at a rate of 2 ml per second for 5 seconds. The substrate was then rotated at 1,500 rpm for 30 seconds, heated at 300°C for 5 minutes in an air atmosphere, and cooled at 23°C for 60 seconds to obtain a substrate with a protective film formed thereon. The formed protective film was observed with an optical microscope for coatability, and rated as "A" (good) when no coating unevenness was observed, "B" (fairly good) when slight coating unevenness was observed, and "C" (poor) when significant coating unevenness was observed.

[0165]

[0166] As is clear from the results in Table 2 above, the protective film-forming composition of the example and the protective film formed therefrom had superior crack resistance, storage stability, weight loss suppression, and coatability compared to the protective film-forming composition of the comparative example and the protective film formed therefrom.

[0167] <Preparation of protective film-forming composition (2)> The base generators and polymerizable compounds used in preparing the protective film-forming composition are shown below. The solvent and radical generator used were the same as those used in the previous examples [B] and [C], respectively. In the following examples 2-1 to 2-5 and comparative example 2-1, unless otherwise specified, parts by mass refer to values ​​where the total mass of the components used is 100 parts by mass.

[0168] [D] Base generator D-1: a compound represented by the following formula (D-1):

[0169] [E] Polymerizable compound E-1: a compound represented by the following formula (E-1):

[0170] Example 2-1 Preparation of protective film-forming composition (J2-1) 41.5 parts by mass of (A-1) as polysiloxane, 58.4 parts by mass of (B-1) as solvent (including the solvent contained in the polysiloxane solution), and 0.07 parts by mass of (D-1) as base generator were mixed, and the resulting solution was filtered through a polytetrafluoroethylene filter having a pore size of 0.2 μm to prepare protective film-forming composition (J2-1).

[0171] [Examples 2-2 to 2-5 and Comparative Example 2-1] Preparation of protective film-forming compositions (J2-2) to (J2-5), (j2-1) Compositions for forming protective films (J2-2) to (J2-5) of Examples 2-2 to 2-5 and composition for forming a protective film (j2-1) of Comparative Example 2-1 were prepared in the same manner as in Example 1, except that the types and amounts of each component shown in Table 3 below were used.

[0172] <Evaluation> The etching solution resistance and strippability of the compositions prepared above were evaluated by the following methods. The evaluation results are shown in Table 3 below.

[0173]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0059]

[0061]

[0059]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098]

[0099]

[0099]

[0100]

[0099]

[0099]

[0101]

[0099]

[0099]

[0099]

[0099]

[0102]

[0099]

[0099]

[0099]

[0103]

[0099]

[0099]

[0099]

[0104]

[0099]

[0099]

[0099]

[0105]

[0099]

[0099]

[0099]

[0106]

[0099]

[0099]

[0110] [

[0174] [Etching Solution Resistance] The substrate with the protective film obtained above was immersed in a 5% aqueous solution of tetramethylammonium hydroxide (TMAH) (60°C) as an etching solution for 15 minutes. The film thickness before and after immersion was measured using a spectroscopic ellipsometer (J.A. WOOLLAM "M2000D"), and the remaining film ratio was calculated from the measured values. The etching solution resistance was evaluated as "A" (very good) when the remaining film ratio relative to the film thickness before immersion was 90% or more, "B" (good) when it was 80% or more but less than 90%, "C" (fair) when it was 70% or more but less than 80%, and "D" (poor) when it was less than 70%.

[0175] The substrate with the protective film obtained above was immersed in a 1% aqueous solution of hydrogen fluoride (20 to 25° C.) for 20 minutes. The peelability was evaluated as "A" (very good) when no residue of the protective film was visible, and as "B" (poor) when residue of the protective film was visible.

[0176]

[0177] As is clear from the results in Table 3 above, the protective film formed using the protective film-forming composition of the example had superior etching solution resistance and peelability compared to the protective film formed using the protective film-forming composition of the comparative example.

[0178] According to the protective film-forming composition of the present invention, a protective film can be formed at the peripheral portion of the substrate, which has good storage stability and coatability, and is excellent in crack resistance, weight loss suppression, etching solution resistance, and peelability. According to the semiconductor substrate manufacturing method of the present invention, the protective film-forming composition is used when forming the protective film at the peripheral portion of the substrate, so that the semiconductor substrate manufacturing yield can be improved. Therefore, these compositions can be suitably used in the manufacture of semiconductor devices, which are expected to become even more miniaturized and highly integrated in the future.

Claims

A composition for forming a protective film on a peripheral portion of a substrate, A polysiloxane having a first structural unit represented by the following formula (1): Solvent and Contains A composition for forming a protective film, wherein the content of the polysiloxane in the components other than the solvent in the composition for forming a protective film is 50 mass % or more. (In the above formula (1), X is a monovalent group having an aromatic ring having 3 to 20 carbon atoms and substituted with a vinyl group or an ethynyl group. a is an integer of 1 to 3. When a is 2 or more, multiple Xs may be the same or different. R １ is a monovalent organic group having 1 to 20 carbon atoms, a hydroxy group, or a halogen atom. b is an integer of 0 to 2. When b is 2, two R １ are the same or different, provided that a + b is 3 or less.) 　 2. The composition for forming a protective film according to claim 1, wherein the polysiloxane has a second structural unit (excluding the first structural unit) represented by the following formula (2): (In the above formula (2), R ２１ and R ２２ are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms. 　 The composition for forming a protective film according to claim 2 , wherein the second structural unit represented by the formula (2) is a structural unit represented by the following formula (2A): (In the above formula (2A), R ２１ and R ２２ has the same meaning as in formula (2) above. n is an integer of 2 to 200.

2. The composition for forming a protective film according to claim 1, wherein the polysiloxane has a third structural unit (excluding the first structural unit and the second structural unit) represented by the following formula (3): (In the above formula (3), R ３１ is a monovalent organic group having 1 to 20 carbon atoms, a hydroxy group, or a halogen atom. c is an integer of 0 to 3. When c is 2 or more, multiple R ３１ are the same or different.) 　 2. The composition for forming a protective film according to claim 1, wherein the content of the first structural unit in all structural units constituting the polysiloxane is 5 mol % or more and 40 mol % or less.

3. The composition for forming a protective film according to claim 2, wherein the content of the second structural unit in all structural units constituting the polysiloxane is 10 mol % or more and 70 mol % or less.

5. The composition for forming a protective film according to claim 4, wherein the content of the third structural unit in all structural units constituting the polysiloxane is 1 mol % or more and 85 mol % or less. 　 The composition for forming a protective film according to claim 1 , which is used in the production of a semiconductor substrate. 　 A method for producing a semiconductor substrate, comprising a step of applying the composition for forming a protective film according to claim 1 directly or indirectly only to the peripheral edge portion of a substrate.

Images