JP2023074176A - Manufacturing method of substrate and coating liquid - Google Patents

Abstract

To provide a manufacturing method of a substrate, enabling selective formation of a film that can exert a high blocking performance against a metal oxide formation by an ALD method or a CVD method by a coating method onto the substrate including a region containing an end terminal structure expressed by Si-NH2 in a front layer, and to provide a coating liquid.SOLUTION: A manufacturing method of a substrate is provided, comprising: a step of coating a coating liquid to a base material having a first region including end terminal structure expressed by Si-NH2 in a front layer; and a step of heating a coating film formed by the coating step. The coating liquid contains a chemical compound having a functional group and an aromatic ring structure, and forming a carbon-nitrogen double bond by being reacted with the end terminal structure of the first region.SELECTED DRAWING: None

Description

The present invention relates to a substrate manufacturing method and a coating liquid.

With further miniaturization of semiconductor devices, a technique for forming fine patterns of 30 nm or less is required. However, the conventional lithographic method is becoming technically difficult due to optical factors and the like.

Therefore, formation of fine patterns using a so-called bottom-up technique has been studied. As this bottom-up technique, for example, a substrate having a fine region on the surface layer is selectively chemically modified, and the substrate is not chemically modified by an ALD (Atomic Layer Deposition) method, a CVD (Chemical Vapor Deposition) method, or the like. A method of forming a pattern on a substrate by removing the above chemical modification after forming a metal oxide in a region and the like have been studied (International Publication No. 2019/023001).

WO2019/023001

In WO2019/023001, a substrate having a first surface with hydrogen termination and a second surface with hydroxide termination is exposed to a nitriding agent to form an amine-terminated first surface. A method is disclosed that includes forming a surface and exposing the amine-terminated first surface to a blocking molecule to form a blocking layer on the first surface.

In the above method, a blocking layer is selectively formed on the amine-terminated surface by immersing the substrate in a solution of undecanal in DMSO. At this time, it is considered that the Si—NH ₂ groups on the substrate surface and the aldehyde groups of undecanal react (dehydration condensation reaction) to form carbon-nitrogen double bonds. However, since this reaction is an equilibrium reaction and is very susceptible to hydrolysis by water in solution or air, it is considered difficult to stably form a blocking layer on a substrate by a coating method.

The present invention selectively forms a film exhibiting high blocking performance against metal oxide formation by ALD or CVD on a substrate having a surface layer containing a region containing a terminal structure represented by Si—NH ₂ by a coating method. An object of the present invention is to provide a method for manufacturing a substrate and a coating liquid capable of achieving the above.

The invention made to solve the above problems is formed by applying a coating liquid to a substrate having a first region including a terminal structure represented by Si—NH ₂ on the surface layer, and the coating step. and heating the applied coating film, wherein the coating liquid contains a compound having a functional group and an aromatic ring structure that reacts with the terminal structure of the first region to form a carbon-nitrogen double bond. It is a method of manufacturing a substrate that

Another invention made to solve the above problems is a coating liquid used to be applied to a substrate having a first region containing a terminal structure represented by Si—NH ₂ on the surface layer, , a coating liquid containing a compound having an aromatic ring structure and a functional group that reacts with the terminal structure of the first region to form a carbon-nitrogen double bond.

According to the method for manufacturing a substrate and the coating solution of the present invention, a metal oxide is selectively applied by an ALD method or a CVD method onto a substrate having a region containing a terminal structure represented by Si—NH ₂ on the surface layer by a coating method. A film can be formed that exhibits high blocking performance against formation.

The method for manufacturing a substrate and the coating liquid of the present invention will be described in detail below.

<Substrate manufacturing method>
The method for producing the substrate includes a step of applying a coating liquid to a substrate having a first region including a terminal structure represented by Si—NH ₂ on the surface layer (hereinafter also referred to as a “coating step”); and a step of heating the coating film formed by the coating step (hereinafter also referred to as a “heating step”).

The method for manufacturing the substrate, having the above configuration, selectively forms a metal oxide by an ALD method or a CVD method on a substrate having a region including a terminal structure represented by Si—NH ₂ on the surface layer by a coating method. It is possible to form a film exhibiting high blocking performance against The reason why the substrate manufacturing method produces the above effects is not necessarily clear, but it can be inferred, for example, as follows.

The coating solution used in the coating step contains the [A] compound described later, and the specific functional group of the [A] compound and the terminal structure represented by Si—NH ₂ are carbon-nitrogen It is believed that the formation of double bonds enables the selective formation of a film on the region having the terminal structure represented by Si—NH ₂ . In addition, it is believed that the hydrolysis of the carbon-nitrogen double bond can be suppressed by the [A] compound having an aromatic ring structure. Furthermore, it is thought that the hydrolysis of the carbon-nitrogen double bond can be further suppressed because the water that causes hydrolysis can be removed by the heating step. Combined with these factors, according to the method for manufacturing the substrate, the substrate having a region including a terminal structure represented by Si—NH ₂ on the surface layer is selectively coated with a metal by an ALD method or a CVD method. It is believed that a film exhibiting high blocking performance against oxide formation can be formed.

The method for manufacturing the substrate includes, after the heating step, a step (hereinafter also referred to as a “cleaning step”) of cleaning, with a cleaning liquid, materials existing in regions other than the first region of the film formed by the heating step. may be provided.

The method for manufacturing the substrate may include a step of depositing a pattern on the surface of the substrate by a CVD method or an ALD method (hereinafter also referred to as a “deposition step”) after the heating step or the cleaning step.

The method for manufacturing the substrate may include, after the heating step, a step of stripping the film formed by the heating step with a stripping solution (hereinafter also referred to as a “peeling step”). A film formed by the substrate manufacturing method can be easily peeled off with a peeling liquid.

Each step included in the method for manufacturing the substrate will be described below.

[Coating process]
In this step, a coating liquid is applied to a base material having a first region including a terminal structure represented by Si—NH ₂ on the surface layer. Through this step, a coating film is formed on the substrate.

A method for applying the coating liquid is not particularly limited, and examples thereof include a spin coating method, a roll coating method, a bar coating method and the like.

(Base material)
The substrate has a first region including a terminal structure represented by Si—NH ₂ (hereinafter also referred to as “primary amino group terminal structure”) on the surface layer. The shape of the substrate is not particularly limited, and may be a desired shape, such as a plate (substrate) or spherical shape.

The substrate may have a region other than the first region (hereinafter also referred to as “second region”) on the surface layer. When the substrate has the second region on the surface layer, a blocking film can be selectively formed on the first region.

When the base material has the second region on the surface layer, the shape of the first region and the second region is not particularly limited, and examples thereof include a planar shape, a dotted shape, a striped shape, and the like in plan view. The sizes of the first region and the second region are not particularly limited, and the regions can be of any desired size.

Examples of the second region include a region containing nonmetallic atoms, a region containing metal atoms, and the like. The number of second regions may be one, or two or more.

Examples of the form in which the non-metal atoms are contained include non-metal simple substances, non-metal oxides, non-metal nitrides, non-metal oxide nitrides, and the like.

Examples of non-metal simple substances include simple substances such as silicon and carbon. Examples of non-metal oxides include silicon oxide and the like. Examples of non-metal oxide nitrides include SiON and the like. Among these, non-metal oxides are preferred, and silicon oxide is more preferred.

The metal atom is not particularly limited as long as it is an atom of a metal element. Silicon is a non-metal atom and does not correspond to a metal atom. Examples of metal atoms include copper, iron, zinc, cobalt, aluminum, tin, tungsten, zirconium, titanium, tantalum, germanium, molybdenum, ruthenium, gold, silver, platinum, palladium, and nickel. Among these, copper, cobalt or tungsten are preferred.

Examples of the form in which metal atoms are contained include elemental metals, alloys, conductive nitrides, metal oxides, silicides, and the like.

Examples of simple metals include simple metals such as copper, iron, cobalt, tungsten, and tantalum. Examples of alloys include nickel-copper alloys, cobalt-nickel alloys, and gold-silver alloys. Examples of conductive nitrides include tantalum nitride, titanium nitride, iron nitride, and aluminum nitride. Examples of metal oxides include tantalum oxide, aluminum oxide, iron oxide, and copper oxide. Examples of silicide include iron silicide and molybdenum silicide. Among these, simple metals are preferred, and simple copper, cobalt or tungsten is more preferred.

In this step, the primary amino group terminal structure in the first region of the substrate surface layer reacts with the functional group of the [A] compound described later to form a carbon-nitrogen double bond.

As a substrate, for example, a substrate containing silicon nitride is subjected to a pretreatment to convert the terminal structure represented by Si—H on the surface layer (hereinafter also referred to as “hydrogen terminal structure”) to a primary amino group terminal structure. and the like. The type of pretreatment is not particularly limited, and includes wet treatment, dry treatment, and the like. Examples of wet processing include processing using concentrated acetic acid, dilute hydrofluoric acid, or the like. Examples of dry processing include plasma processing.

In addition, in the method for manufacturing the substrate, before the coating step, a step of performing a pretreatment for converting the hydrogen terminal structure in the surface layer of the substrate containing silicon nitride to a primary amino group terminal structure (hereinafter referred to as "pretreatment (also referred to as "process").

(Coating liquid)
The coating liquid used in this step will be described in the section <Coating liquid> below.

[Heating process]
In this step, the coating film formed by the coating step is heated. This step promotes the reaction between the primary amino group terminal structure and the functional group of the [A] compound. In addition, since water in the system can be removed by this step, hydrolysis of the carbon-nitrogen double bond formed by the above reaction can be suppressed.

The heating means is not particularly limited, and known heating means such as an oven and a hot plate can be used. The heating temperature and heating time can be appropriately determined in consideration of various factors such as the presence or absence of a solvent in the coating liquid, the structure of the [A] compound, the type of the functional group of the [A] compound, and the like. The lower limit of the heating temperature is preferably 80°C, more preferably 100°C, and even more preferably 130°C. The upper limit of the heating temperature is preferably 400°C, more preferably 300°C, and even more preferably 200°C. The lower limit of the heating time is preferably 10 seconds, more preferably 1 minute, and even more preferably 2 minutes. The upper limit of the heating time is preferably 60 minutes, more preferably 10 minutes, and even more preferably 5 minutes.

The average thickness of the formed film can be set to a desired value by appropriately selecting conditions such as the type and concentration of the [A] compound in the coating solution, and the heating temperature and heating time in the heating step. The lower limit of the average thickness of the film is preferably 0.1 nm, more preferably 1 nm, and even more preferably 3 nm. The upper limit of the average thickness is, for example, 20 nm. The average thickness of the film is a value measured using a spectroscopic ellipsometer ("M2000D" manufactured by JA WOOLLAM).

[Washing process]
In this step, the material of the film formed by the heating step, which is present in regions other than the first region, is washed with a cleaning liquid. This step is performed after the heating step. This step removes material that does not form a carbon-nitrogen double bond with the terminal structure in the first region present on the substrate. This step is particularly advantageous when the substrate has a second region, and can remove material present on the second region and selectively form a blocking film on the first region.

An organic solvent is used as the cleaning liquid. Examples thereof include solvents exemplified as [B] solvent described in the section <Coating liquid> below. Moreover, when the coating liquid contains the [B] solvent, the same solvent as the [B] solvent contained in the coating liquid can be used as the cleaning liquid.

[Deposition process]
In this step, a pattern is deposited on the surface of the substrate by CVD or ALD. This step is performed after the heating step or the washing step. This step is particularly advantageous when the substrate has a second region, and the film formed on the first region has high blocking performance against metal oxide formation by CVD or ALD. A metal oxide pattern can be selectively formed thereon.

[Peeling process]
In this step, the film formed by the heating step is removed with a remover. This step is performed after the heating step or the deposition step. This step is particularly advantageous when the substrate has a second region and is performed after the deposition step described above, where the film formed by the heating step is peeled off onto the second region of the substrate. A metal oxide pattern can be selectively formed.

As the stripping liquid, a liquid containing an acid or a liquid containing a base is preferable. Examples of acids include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid and hydrofluoric acid, and carboxylic acids such as acetic acid, citric acid, oxalic acid, maleic acid, isobutyric acid and 2-ethylhexanoic acid. Among these, carboxylic acids are preferred, and citric acid is more preferred. Bases include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, tri ethanolamine, tetramethylammonium hydroxide (TMAH) and the like. Among these, TMAH is preferred.

Examples of stripping solutions include ammonium hydroxide-hydrogen peroxide aqueous solution (SC-1 cleaning solution) and hydrochloric acid-hydrogen peroxide aqueous solution (SC-2 cleaning solution).

The solvent of the stripping solution preferably contains water as a main component. The lower limit of the content of water in the solvent is preferably 50% by mass, more preferably 90% by mass, and even more preferably 95% by mass. The content ratio may be 100% by mass.

<Coating liquid>
The coating liquid contains a functional group and an aromatic ring structure that react with the terminal structure (primary amino group terminal structure) represented by Si—NH ₂ in the first region of the substrate to form a carbon-nitrogen double bond. (hereinafter also referred to as "[A] compound"). The coating liquid is liquid at normal temperature and normal pressure, and may contain a solvent (hereinafter also referred to as "[B] solvent") as necessary. The coating liquid may contain components other than the [A] compound and [B] solvent (hereinafter also referred to as “other components”) within a range that does not impair the effects of the present invention.

The coating liquid is used so as to be coated on a base material having a first region containing a primary amino group terminal structure on the surface layer. Specifically, the coating liquid is used in the coating step in the substrate manufacturing method described above.

Each component contained in the coating liquid will be described below.

[[A] compound]
[A] The compound has a functional group (hereinafter also referred to as "functional group (X)") that reacts with the primary amino group terminal structure in the first region of the substrate to form a carbon-nitrogen double bond and an aromatic ring. have a structure.

The [A] compound may be a polymer (hereinafter also referred to as "[A1] polymer") or a low molecular weight compound (hereinafter also referred to as "[A2] compound"). As used herein, the term "polymer" means a compound having a repeating unit, and the term "low-molecular compound" means a compound that is not a polymer, has no molecular weight distribution, and has a molecular weight of 1,000 or less. means

The functional group (X) is a functional group that reacts with the primary amino group terminal structure to form a carbon-nitrogen double bond. As the functional group (X), an aldehyde group or a ketonic carbonyl group is preferred. The [A] compound may have one or more functional groups (X).

Examples of the aromatic ring structure include aromatic hydrocarbon ring structures with 6 to 20 ring members, aromatic heterocyclic structures with 5 to 20 ring members, and the like. The "number of ring members" means the number of atoms constituting a ring structure, and in the case of a polycyclic ring, the total number of atoms constituting the polycyclic ring.

Examples of aromatic hydrocarbon ring structures having 6 to 20 ring members include benzene structure, naphthalene structure, biphenyl structure, anthracene structure, phenanthrene structure, fluorene structure, tetracene structure and pyrene structure.

Examples of aromatic heterocyclic structures having 5 to 20 ring members include furan structure, benzofuran structure, pyrrole structure, indole structure, thiophene structure, benzothiophene structure, dibenzothiophene structure, imidazole structure, pyrazole structure, oxazole structure and the like.

As the aromatic ring structure, an aromatic hydrocarbon ring structure having 6 to 20 ring members is preferred.

The [A] compound preferably has a molecular weight of 200 or more. In addition, "molecular weight" means the weight average molecular weight Mw described later in the case of the [A1] polymer, and the sum of the atomic weights of each atom constituting the low-molecular compound in the case of the [A2] compound. do.

([A1] compound)
When the [A] compound is a [A1] polymer, the [A1] polymer has a structural unit containing an aromatic ring structure (hereinafter also referred to as "structural unit (I)") and a functional group (X). [A1] The polymer may have structural units other than the structural unit (I).

When the functional group (X) is an aldehyde group, the [A1] polymer preferably has the functional group (X) at the terminal of the main chain or the terminal of the side chain, and the functional group (X) is at the terminal of the main chain. It is more preferable to have "Main chain" means the longest atomic chain among the atomic chains constituting the [A1] polymer, and "side chain" means the atomic chain other than the main chain among the atomic chains constituting the [A1] polymer. means

The functional group (X) at the terminal of the main chain can be introduced, for example, by treating the polymerization terminal of a living anionic polymer such as polystyrene with a terminal treating agent that provides the functional group (X). Examples of terminal treating agents that provide functional groups (X) include N,N-dimethylformamide.

The [A1] polymer having a functional group (X) at the end of the side chain is a monomer having a functional group (X) at the end and an ethylenic carbon-carbon double bond, such as 4-vinylbenzaldehyde. It can be formed, for example, by using a body.

When the functional group (X) is a ketonic carbonyl group, the [A1] polymer preferably has the functional group (X) in its main chain. Moreover, both ends of the ketonic carbonyl group are preferably bonded to the aromatic ring structure. A ketonic carbonyl group in the main chain is formed by combining a compound having an aromatic ring structure such as 2,2′-dimethoxybiphenyl and an aromatic dicarboxylic acid such as 4,4′-dicarboxydiphenyl ether with the presence of trofluoromethanesulfonic acid. It can be formed by the Friedel-Crafts reaction by reacting below.

When the [A] compound is the [A1] polymer, the lower limit of the weight average molecular weight Mw of the [A1] polymer is preferably 200, more preferably 1,000, even more preferably 2,000, and 3,000. is more preferred, and 4,000 is particularly preferred. The upper limit of Mw is preferably 80,000, more preferably 60,000, sometimes preferably 20,000, and sometimes preferably 10,000.

[A1] The upper limit of the ratio of Mw to the polystyrene-equivalent number average molecular weight Mn of the polymer (Mw/Mn, dispersity) is preferably 5, more preferably 2.5, and sometimes preferably 1.5. , 1.3 may be preferred. The lower limit of the above ratio is usually 1, preferably 1.02.

[Method for measuring Mw and Mn]
The Mw and Mn of the polymer herein are obtained by gel permeation chromatography using Tosoh Corporation GPC columns (two "G2000HXL", one "G3000HXL" and one "G4000HXL") under the following conditions: It is a value measured by graphics.
Eluent: Tetrahydrofuran (Fujifilm Wako Pure Chemical Industries, Ltd.)
Flow rate: 1.0 mL/min Sample concentration: 1.0% by mass
Sample injection volume: 100 μL
Column temperature: 40°C
Detector: Differential refractometer Standard material: Monodisperse polystyrene

([A2] compound)
When the [A] compound is the [A2] compound, the [A2] compound has an aromatic ring structure and a functional group (X). In the [A2] compound, the functional group (X) is preferably bound to the aromatic ring structure. In this case, the blocking film can be more stably formed on the substrate by a coating method.

Examples of the [A2] compound include p-octyloxybenzaldehyde and 3,5-bis(dodecyloxy)benzaldehyde.

When the [A] compound is the [A2] compound, the lower limit of the molecular weight of the [A2] compound is preferably 200, more preferably 300. [A2] When the molecular weight of the compound is at least the above lower limit, the coatability of the coating liquid can be further improved. The upper limit of the molecular weight is 1,000, preferably 700, more preferably 600.

[[B] solvent]
The [B] solvent is not particularly limited as long as it is a solvent capable of dissolving or dispersing the [A] compound and other components, such as alcohol solvents, ether solvents, ketone solvents, amide solvents, and ester solvents. , hydrocarbon solvents, and the like. The coating liquid may contain one or more [B] solvents.

Examples of alcohol solvents include aliphatic monoalcohol solvents having 1 to 18 carbon atoms such as 4-methyl-2-pentanol and n-hexanol;
Alicyclic monoalcohol solvents having 3 to 18 carbon atoms such as cyclohexanol;
Polyhydric alcohol solvents having 2 to 18 carbon atoms such as 1,2-propylene glycol;
Polyhydric alcohol partial ether solvents having 3 to 19 carbon atoms such as propylene glycol monomethyl ether are included.

Examples of ether solvents include dialkyl ether solvents such as diethyl ether, dipropyl ether, dibutyl ether, dipentyl ether, diisoamyl ether, dihexyl ether, and diheptyl ether;
Cyclic ether solvents such as tetrahydrofuran and tetrahydropyran;
aromatic ring-containing ether solvents such as diphenyl ether and anisole (methylphenyl ether);

Ketone solvents include, for example, acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl isobutyl ketone (MIBK), 2-heptanone (methyl-n-pentyl ketone), ethyl-n- Chain ketone solvents such as butyl ketone, methyl-n-hexyl ketone, di-iso-butyl ketone, and trimethyl nonanone;
Cyclic ketone solvents such as cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, methylcyclohexanone;
2,4-pentanedione, acetonylacetone, acetophenone and the like.

Examples of amide solvents include cyclic amide solvents such as N,N'-dimethylimidazolidinone and N-methylpyrrolidone;
Chain amide solvents such as N-methylformamide, N,N-dimethylformamide, N,N-diethylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpropionamide, and the like.

Examples of ester solvents include monocarboxylic acid ester solvents such as n-butyl acetate and ethyl lactate;
Polyhydric alcohol carboxylate solvents such as propylene glycol acetate;
Polyhydric alcohol partial ether carboxylate solvents such as propylene glycol monomethyl ether acetate;
Lactone solvents such as γ-butyrolactone and δ-valerolactone;
Polyvalent carboxylic acid diester solvents such as diethyl oxalate;
Examples thereof include carbonate-based solvents such as dimethyl carbonate, diethyl carbonate, ethylene carbonate and propylene carbonate.

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

Among these, ester solvents are preferred, polyhydric alcohol partial ether carboxylate solvents, lactone solvents, or combinations thereof are more preferred, and propylene glycol monomethyl ether acetate, γ-butyrolactone, or combinations thereof are even more preferred.

[Other ingredients]
Other components include, for example, acid generators and surfactants. The content of other components in the coating liquid can be appropriately determined depending on the type of other components used.

The lower limit of the solid content concentration of the coating liquid is preferably 0.1% by mass, more preferably 0.5% by mass, and even more preferably 0.7% by mass. The upper limit of the solid content concentration is preferably 30% by mass, more preferably 10% by mass, and even more preferably 3% by mass. "Solid content concentration" refers to the concentration (% by mass) of all components other than the [B] solvent in the coating liquid.

[Method for preparing coating liquid]
The coating liquid is, for example, a mixture of [A] compound, [B] solvent and, if necessary, other components in a predetermined ratio, and is preferably filtered through a high-density polyethylene filter or the like having pores of 0.45 μm or less. It can be prepared by

EXAMPLES The present invention will be specifically described below based on Examples, but the present invention is not limited to these Examples. The method for measuring each physical property value is shown below.

[Weight average molecular weight (Mw), number average molecular weight (Mn) and dispersity (Mw/Mn)]
The Mw and Mn of the polymer were measured according to the conditions described in the section [Method for measuring Mw and Mn] above. The dispersity (Mw/Mn) of the polymer was calculated from the measurement results of Mw and Mn.

[ ¹³ C-NMR analysis]
¹³ C-NMR analysis was performed using a nuclear magnetic resonance apparatus (“JNM-EX400” manufactured by JEOL Ltd.) using CDCl ₃ as a measurement solvent. The content ratio of each structural unit in the polymer was calculated from the area ratio of the peak corresponding to each structural unit in the spectrum obtained by ¹³ C-NMR.

<Synthesis of [A] compound>
Among the [A] compounds, polymers (A1-1) to (A1-3) were synthesized as the [A1] polymer, and the following compound (A2-1) was synthesized as the [A2] compound. In addition, polymers (a1-1) to (a1-3) were synthesized as controls for the [A1] polymer.

[Synthesis Example 1] Synthesis of polymer (A1-1) (BZP-co-BP(OMe)2) In a three-necked flask equipped with a thermometer and a stirrer bar, 7.8 g of 4,4'-dicarboxydiphenyl ether, 2 , 2′-dimethoxybiphenyl and 45 mL of trifluoromethanesulfonic acid were added, and the mixture was heated and stirred at 40° C. for 24 hours under a nitrogen atmosphere. After completion of the reaction, 45 mL of water was slowly added dropwise to precipitate a polymer, which was recovered using a Buchner funnel and dried under reduced pressure. This polymer is dissolved in a small amount of N,N-dimethylacetamide, precipitated and purified in 2-propanol, recovered with a Buchner funnel, and dried under reduced pressure to obtain a polymer represented by the following formula (A1-1) (hereinafter , also referred to as “polymer (A1-1)” or “BZP-co-BP(OMe)2”) was obtained in an amount of 12.8 g. Polymer (A1-1) had Mw of 50,000, Mn of 24,800, and Mw/Mn of 2.02.

[Synthesis Example 2] Synthesis of polymer (A1-2) (PS-r-PStCHO) 10 g of methyl ethyl ketone was placed in a three-necked flask equipped with a thermometer, a Dimroth condenser and a stirrer bar and maintained at 80 ° C., and 7.28 g of styrene was added. , 4-vinylbenzaldehyde 3.96 g, dimethyl-2,2′-azobis(2-methylpropionate) 0.69 g and methyl ethyl ketone 20 g was dropped from a feeder for 3 hours. After completion of dropping, the mixture was aged at 80° C. for 3 hours. By purifying the obtained polymerization solution by precipitation with 5 times the amount of methanol, a white solid polymer represented by the following formula (A1-2) (hereinafter, “polymer (A1-2)” or “PS-r -PStCHO”) was obtained. The polymer (A-2) had an Mw of 5,780, an Mn of 3,140, and an Mw/Mn of 1.84. ¹³ C-NMR analysis revealed that the molar ratio of structural units derived from styrene and structural units derived from 4-vinylbenzaldehyde in the polymer (A1-2) was 58:42.

[Synthesis Example 3] Synthesis of polymer (A1-3) (PS-w-CHO) After drying a 500 mL flask reaction vessel under reduced pressure, 120 g of tetrahydrofuran (THF) subjected to distillation dehydration treatment was injected under a nitrogen atmosphere. , cooled to -78°C. Next, 2.38 mL of a 1N cyclohexane solution of sec-butyllithium (sec-BuLi) was poured into this THF, and then the styrene 13. was subjected to adsorption filtration with silica gel and distillation dehydration treatment to remove the polymerization inhibitor. 3 mL was added dropwise over 30 minutes, and the polymerization system was confirmed to be orange. Care was taken so that the internal temperature of the reaction solution did not exceed −60° C. during this dropwise injection. After completion of dropping, the mixture was aged for 30 minutes. Thereafter, 0.18 ml of N,N-dimethylformamide was injected to terminate the polymerization terminal. The temperature of this reaction solution was raised to room temperature, and the resulting reaction solution was concentrated and substituted with methyl isobutyl ketone (MIBK). 1,000 g of an aqueous 2% oxalic acid solution was added to the resulting solution, stirred, and allowed to stand, after which the lower aqueous layer was removed. This operation was repeated three times to remove the metal salt. After that, 1,000 g of ultrapure water was poured and stirred to remove the lower water layer. This operation was repeated three times to remove oxalic acid, then the solution was concentrated and dropped into 500 g of methanol to precipitate a polymer, and a solid was recovered using a Buchner funnel. By drying this solid under reduced pressure at 60 ° C., a white polymer represented by the following formula (A-3) (hereinafter also referred to as “polymer (A1-3)” or “PS-w-CHO”) 11 .9 g was obtained. Polymer (A1-3) had Mw of 5,000, Mn of 4,800, and Mw/Mn of 1.04.

[Synthesis Example 4] Synthesis of compound (A2-1) (3,5-bis(dodecyloxy)benzaldehyde) In a 1 L eggplant-shaped flask, 8.37 g of 3,5-dihydroxybenzaldehyde, 44.5 g of 1-bromododecane, N, 300 g of N-dimethylformamide and 20.7 g of potassium carbonate were added, and the mixture was heated and stirred at 80° C. for 16 hours under a nitrogen atmosphere. After cooling, potassium carbonate and salts were removed with a Kiriyama funnel (registered trademark), and then washed with toluene/ultra-pure water four times. After collecting the organic layer and removing water with anhydrous sodium sulfate, the filtrate was collected with a folded filter paper and concentrated under reduced pressure. Next, purification is performed by column chromatography with hexane/methylene chloride=10/1 to obtain 32 g of white solid 3,5-bis(dodecyloxy)benzaldehyde (hereinafter also referred to as "compound (A2-1)"). Obtained. The molecular weight of compound (A2-1) was 474.

[Synthesis Example 5] Synthesis of polymer (a1-1) (PS-w-(CN)2) 10.0 g of polymer (A1-3) obtained in Synthesis Example 3 was dissolved in 40 g of toluene, .21 g, 0.25 g of ammonium acetate and 0.038 g of acetic acid were added, and the mixture was heated to dry distillation at 115° C. for 4 hours under a nitrogen atmosphere. The temperature of this reaction solution was raised to room temperature, and the resulting reaction solution was concentrated and substituted with MIBK. 500 g of a 2% aqueous solution of sodium hydrogencarbonate was added to the obtained solution, and the mixture was stirred, allowed to stand, and then the lower aqueous layer was removed. This operation was repeated three times. After that, 1,000 g of ultrapure water was poured and stirred to remove the lower water layer. After repeating this operation three times, the solution was concentrated and added dropwise to 500 g of methanol to precipitate a polymer, and the solid was recovered using a Buchner funnel. By drying this solid under reduced pressure at 60 ° C., a white polymer represented by the following formula (a1-1) (hereinafter also referred to as “polymer (a1-1)” or “PS-w-(CN)2” 9.8 g were obtained. Polymer (a1-1) had Mw of 5,300, Mn of 5,100, and Mw/Mn of 1.04.

[Synthesis Example 6] Synthesis of polymer (a1-2) (PS-w-PO3Et2) After drying a 500 mL flask reaction vessel under reduced pressure, 120 g of THF that had undergone distillation and dehydration treatment was added under a nitrogen atmosphere, and the temperature was -78°C. cooled to After that, 2.30 mL of a 1N cyclohexane solution of sec-BuLi was injected into this THF, and then 13.3 mL of styrene that had been subjected to adsorption filtration with silica gel and distillation dehydration treatment to remove the polymerization inhibitor was added to the reaction solution. The mixture was added dropwise over 30 minutes while taking care that the temperature did not exceed -60°C, followed by stirring for 30 minutes. Thereafter, 0.33 ml of diethyl chlorophosphate was injected to terminate the polymerization terminal. The temperature of this reaction solution was raised to room temperature, and the resulting reaction solution was concentrated and substituted with MIBK. Then, 200 g of a 2% by mass aqueous solution of oxalic acid was poured into the mixture, and the mixture was stirred, allowed to stand still, and then the lower aqueous layer was removed. This operation was repeated three times to remove the lithium salt. After that, 200 g of ultrapure water was poured and stirred to remove the lower aqueous layer. This operation was repeated four times to remove oxalic acid, then the solution was concentrated and dropped into 400 g of methanol to precipitate a polymer, and a solid was recovered using a Buchner funnel. By drying this solid under reduced pressure at 60° C., a white polymer represented by the following formula (a1-2) (hereinafter also referred to as “polymer (a1-2)” or “PS-w-PO3Et2”) 11 .5 g was obtained. Polymer (a1-2) had Mw of 5,100, Mn of 4,900 and Mw/Mn of 1.04.

[Synthesis Example 7] Synthesis of Polymer (a1-3) (PS-w-PO3H2) To 10.0 g of polymer (a1-2) obtained in Synthesis Example 6, 0.81 g of triethylamine, 4 g of 40 g of propylene glycol monomethyl ether acetate was added, and the mixture was heated and stirred at 80° C. for 6 hours in a nitrogen atmosphere. The temperature of this reaction solution was raised to room temperature, and the resulting reaction solution was concentrated and substituted with MIBK. After that, 200 g of ultrapure water was poured and stirred to remove the lower aqueous layer. This operation was repeated three times to remove triethylamine, and then the solution was concentrated and added dropwise to 400 g of methanol to precipitate a polymer, and a solid was recovered using a Buchner funnel. By drying this solid under reduced pressure at 60° C., a white polymer represented by the following formula (a1-3) (hereinafter also referred to as “polymer (a1-3)” or “PS-w-PO3H2”) 9 .2 g was obtained. Polymer (a1-3) had Mw of 5,100, Mn of 4,800 and Mw/Mn of 1.06.

<Preparation of coating solution>
The [B] solvent used for preparing the coating liquid is shown below.
Solvent (B-1): propylene glycol monomethyl ether acetate (PGMEA)
Solvent (B-2): γ-butyrolactone

[Example 1-1] Preparation of coating liquid (S-1) [A] 1.30 g of polymer (A-1) as compound, [B] 79 g of solvent (B-1) as solvent and solvent After adding 19.8 g of (B-2) and stirring, the mixture was filtered through a high-density polyethylene filter having pores of 0.45 μm to prepare a coating liquid (S-1). The solid content concentration of the coating liquid (S-1) was 1.2%.

[Examples 1-2 to 1-4 and Comparative Examples 1-1 to 1-3] Preparation of coating solutions (S-2) to (S-4) and (CS-1) to (CS-3) below Coating solutions (S-2) to (S-4) and (CS-1) to (CS -3) was prepared. The solid content concentrations of the coating solutions (S-2) to (S-4) and (CS-1) to (CS-3) are also shown in Table 1 below.

<Formation of film>
[substrate]
As the substrate, the following substrate was used.
th-SiO ₂ : 8-inch silicon dioxide substrate with thermal oxide film SiN: 8-inch silicon nitride substrate Cu: 8-inch copper substrate Co: 8-inch cobalt substrate W: 8-inch tungsten substrate Plasma treatment with N ₂ / (3%) H ₂ mixed gas ([Conditions] 25 ° C., chamber pressure: 30 Pa, treatment time: 5 minutes, flow rate: 300 sccm) , Microwave: 300 mW) was used. This plasma treatment converts the Si—H terminal structure existing on the surface layer of the SiN substrate into a Si—NH ₂ terminal structure.

[Example 2-1]
Various substrates shown in Table 2 below are cut into 3 cm × 3 cm, and the composition (S-1) prepared above is applied using a spin coater (“MS-B300” from Mikasa Co., Ltd.) at 1,500 rpm for 20 seconds. to form a coating film (coating step). Next, the substrate on which this coating film was formed was baked at 150° C. for 180 seconds to form a film (heating step). After that, the substrate was washed using propylene glycol monomethyl ether acetate (washing step). In the cleaning step, if the film is not adsorbed on the substrate surface, the non-adsorbed film is removed.

The static contact angle of the surface of the substrate that has undergone a series of treatments including the above coating step, heating step and washing step is measured using a contact angle meter (“Drop master DM-501” manufactured by Kyowa Interface Science Co., Ltd.). The angle was 38° for the th-SiO ₂ substrate, 85° for the SiN substrate, 36° for the Cu substrate, 40° for the Co substrate, and 42° for the W substrate. The static contact angle values of the various substrates before the above treatment were 36° for the th- _SiO2 substrate, 25° for the SiN substrate, 36° for the Cu substrate, 42° for the Co substrate and 45° for the W substrate. , it can be seen that the film is selectively formed on the SiN substrate whose static contact angle is greatly increased compared to the static contact angle before the above treatment.

[Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-3]
The static contact angle was measured in the same manner as in Example 2-1 except that the coating solution shown in Table 2 below was used. The results are shown in Table 2 below.

In Table 2 below, the numerical values written in parentheses after the names of various substrates indicate the static contact angles (Blank SCA) of the various substrates before treatment.

<Evaluation of wet peelability of film>
[Example 3-1]
Various substrates subjected to a series of treatments in Example 2-1 were immersed in a petri dish poured with a 2% by mass citric acid aqueous solution for 3 minutes, and further immersed in a petri dish poured with a 2.38% by mass aqueous tetramethylammonium hydroxide solution for 3 minutes. soaked for a minute. Then, after washing with propylene glycol _monomethyl ether acetate, the static contact angle of the substrate surface was measured using the above contact angle meter. was 32°, the Co substrate was 38°, and the W substrate was 42°. The values of the static contact angles of various substrates before the wet peeling process (Example 2-1) were 38° for the th- _SiO2 substrate, 85° for the SiN substrate, 34° for the Cu substrate, and 40° for the Co substrate. and the W substrate were at 42°, it can be seen that the film formed on the SiN substrate was peeled off by wet.

[Examples 3-2 to 3-4 and Comparative Examples 3-1 to 3-3]
The same treatment as in Example 3-1 was performed except that various substrates that were subjected to a series of treatments in Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-3 were used. measured the angle. The results are shown in Table 3 below.

In Table 3 below, the numerical values written in parentheses for the names of various substrates indicate the static contact angles (Blank SCA) of the various substrates before treatment in the section <Formation of film> above. In Table 3 below, the values for "before peeling" are all the values in Table 2 above.

<Metal oxide blocking evaluation>
[Example 4-1]
For the surface of the SiN substrate subjected to a series of treatments in Example 2-1, metal oxide blocking evaluation was performed to measure the degree of inhibition of oxide layer formation by ALD in order to evaluate the state of film formation. As a control, a SiN substrate was used before being subjected to a series of treatments in Example 2-1.

[Oxide layer formation by ALD]
ALD was performed using Cambridge Nanotech FIJI at Stanford University under the conditions shown in Table 4 below. Trimethylaluminum was used as the precursor, and water was used as the promoter. ALD cycles were fixed at 47 cycles.

[ESCA analysis]
The Al component on the surface of the SiN substrate after ALD was quantified by ESCA analysis. In the ESCA analysis, the Al component was quantified by Al2p (72-78 eV), excluding the film component and the substrate component from the condition of 100 μmφ using “Quantum 2000” manufactured by ULVAC. After that, using the quantitative value of the Al component measured for the SiN substrate before performing a series of treatments in Example 2-1 as a reference, the blocking rate (%) was defined as how much the quantitative value decreased from the reference quantitative value. Calculated. As a result, the blocking rate of the SiN substrate using the coating liquid S-1 was 98.6%. A higher blocking ratio indicates a higher ability to block metal oxides, so it can be seen that the film formed on the SiN substrate has a higher ability to block metal oxide formation by the ALD method.

[Examples 4-2 to 4-4 and Comparative Examples 4-1 to 4-3]
The same treatment as in Example 4-1 was performed except that the SiN substrates subjected to a series of treatments in Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-3 were used, respectively, and the blocking rate was Calculated. The results are shown in Table 5 below. All of the examples had excellent blocking performance, whereas the comparative examples had almost no blocking performance.

Claims (9)

A step of applying a coating liquid to a substrate having a first region including a terminal structure represented by Si—NH ₂ on the surface layer;
A step of heating the coating film formed by the coating step,
A method for producing a substrate, wherein the coating liquid contains a compound having a functional group that reacts with the terminal structure of the first region to form a carbon-nitrogen double bond and an aromatic ring structure. 2. The method of manufacturing a substrate according to claim 1, wherein the compound has a molecular weight of 200 or more. 3. The method for manufacturing a substrate according to claim 1, wherein the compound is a polymer having a structural unit containing an aromatic ring structure. 4. The method of manufacturing a substrate according to claim 3, wherein the polymer has the functional group at the terminal of the main chain or the terminal of the side chain. 5. The method for producing a substrate according to any one of claims 1 to 4, wherein the functional group is an aldehyde group or a ketonic carbonyl group. 6. The method for producing a substrate according to claim 1, wherein the aromatic ring structure is an aromatic hydrocarbon ring structure. 7. The method for producing a substrate according to any one of claims 1 to 6, wherein the substrate further has a second region containing silicon oxide on the surface layer. 8. The method for manufacturing a substrate according to any one of claims 1 to 7, wherein the coating liquid further contains a solvent. A coating liquid used to be applied to a substrate having a first region containing a terminal structure represented by Si—NH ₂ on the surface layer,
A coating liquid containing a compound having an aromatic ring structure and a functional group that reacts with the terminal structure of the first region to form a carbon-nitrogen double bond.