TWI887524B - Method for manufacturing multi-layer wiring board, kit for forming laminated film, and composition - Google Patents

Abstract

The present invention provides a method for manufacturing a multi-layer wiring substrate that can form an organic film with excellent adhesion to a plating layer on the inner wall surface of a through hole and has excellent metal embedding property into the through hole by plating treatment. The multi-layer wiring substrate is manufactured by the following method, which includes: a first forming step of forming a first organic film 16 on the wiring 13 formed on the inner side of the through hole 11 on the insulating layer 14 provided on the wiring 13; a second forming step of forming a second organic film 17 on the inner wall surface of the through hole 11 after forming the first organic film 16; a removing step of removing the first organic film 16 after forming the second organic film 17; and a plating step of forming a plating layer 18 inside the through hole 11 after removing the first organic film 16. The second organic film 17 is formed using a polymer (I) having a first functional group that can interact with a group on the surface of the insulating layer 14 , and has a second functional group that can form a bond with a metal included in the coating layer 18 .

Description

Method for manufacturing multi-layer wiring board, kit for forming laminated film, and composition

The present invention relates to a method for manufacturing a multi-layer wiring substrate, a kit for forming a laminated film, and a composition.

In the semiconductor manufacturing process, as a method of forming multi-layer wiring on a semiconductor wafer, there is a known technique of forming a through hole in an interlayer insulating film and embedding metal into the inside of the through hole by plating. In this technique, in order to suppress the diffusion of the metal filled into the inside of the through hole into the insulating film, a barrier film is formed on the inner wall surface of the through hole before embedding the metal (for example, refer to Patent Document 1).

Patent document 1 discloses the following: a monomolecular film is formed on the bottom surface of a through hole of a wafer having a through hole formed on an insulating film on the wiring using a silane coupling agent or a titanium coupling agent, and then a barrier film including a Co-W-B alloy is formed on the side surface of the through hole or the upper surface of the insulating film, and then the monomolecular film is removed, and then the wiring exposed on the bottom surface of the through hole is used as a catalyst to form an electroless plating film from the bottom surface of the through hole, thereby burying the metal into the inside of the through hole.

[Prior art literature]

[Patent Literature]

[Patent Document 1] International Publication No. 2019/151078

In the semiconductor manufacturing process, further miniaturization is being studied to meet the requirements of large capacity or high speed. In addition, attempts are being made to develop new materials to achieve micro-processing. For the barrier film formed inside the through hole in the multi-layer wiring formation step, new materials with higher performance are also required to replace the previous metal layer. Regarding the performance as a barrier film, in addition to the adhesion with the insulating film, there is also excellent adhesion with the metal embedded in the through hole, less voids or seams in the metal embedded in the through hole, and excellent metal embedding performance.

The present invention is made in view of the above-mentioned subject, and its main purpose is to provide a method for manufacturing a multi-layer wiring board that can form an organic film with excellent adhesion to the plating layer on the inner wall surface of the through hole and has excellent metal embedding properties in the through hole through plating treatment.

In order to solve the above-mentioned problem, the following means can be provided according to the present invention.

[1] A method for manufacturing a multi-layer wiring substrate, comprising: a first forming step of forming a first organic film on the wiring inside a through hole, wherein the through hole is formed in an insulating layer provided on the wiring so as to penetrate the insulating layer in a thickness direction; and a second forming step of forming a second organic film on the inner wall surface of the through hole after forming the first organic film. an organic film; a removal step of removing the first organic film after forming the second organic film; and a plating step of forming a metal layer by plating treatment in the interior of the through hole after removing the first organic film, wherein the second organic film is formed using a polymer (I) having a first functional group that can interact with a group on the surface of the insulating layer and having a second functional group that can form a bond with the metal contained in the metal layer.

[2] A kit for forming a laminated film, used for pre-treatment for forming a metal layer inside a through hole of a multi-layer wiring board by plating treatment, the kit comprising: a polymer (I) having a functional group and a cross-linking group, wherein the functional group can form a bond with at least one group selected from the group consisting of a hydrogen atom, a hydroxyl group, a pendoxy group and -N( ^R1 ) ₂ (wherein ^R1 is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms) bonded to a silicon atom; and a polymer (II) having a functional group that can form a bond with the cross-linking group.

[3] A composition for use in a pretreatment for forming a metal layer inside a through hole of a multilayer wiring board by plating treatment, the composition comprising: a polymer having a functional group and a crosslinking group which is at least one selected from the group consisting of anhydride groups and protected carboxyl groups, the functional group being capable of interacting with a group which is bonded to a silicon atom and which is at least one selected from the group consisting of a hydrogen atom, a hydroxyl group, a pendoxy group and -N( ^R1 ) ₂ (wherein ^R1 is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms); and a solvent.

According to the manufacturing method of the present invention, an organic film having excellent adhesion to the coating layer can be formed on the inner wall surface of the through hole. In addition, the embedding property of the metal treated by coating is excellent in the through hole in which the organic film is formed on the inner wall surface by the manufacturing method of the present invention. According to the manufacturing method of the present invention, an organic film showing such excellent characteristics can be obtained by simple operations such as coating.

10:Wiring board

11:Through hole

12: Inner wall surface

13:Wiring

14: Insulation layer

15: Bottom

16: The first organic film

17: Second organic film

17a: First floor

17b: Second level

18: Plating layer

Figure 1 is a schematic diagram showing the steps of forming an organic film inside a through hole. (a) shows before the organic film is formed, (b) shows after the first organic film is formed, (c) shows after the first layer of the second organic film is formed, (d) shows after the second layer of the second organic film is formed, (e) shows after the first organic film is removed, and (f) shows after the coating layer is formed.

The following is a detailed description of matters related to the implementation method. In addition, in this manual, the numerical range recorded using "~" means that the numerical values recorded before and after "~" are included as the lower limit and upper limit.

《Manufacturing method of multi-layer wiring board》

The manufacturing method disclosed herein (hereinafter, also referred to as "the present manufacturing method") is a wiring forming step for forming multi-layer wiring on a substrate to obtain a multi-layer wiring substrate, including a step of forming an organic film on the inner wall surface of a through hole provided on an insulating layer on the wiring as a pre-treatment for the step of embedding metal into the inside of the through hole by plating. The organic film is formed using a selective surface modification composition as an organic material. The organic film formed on the inner wall surface of the through hole has a barrier function of inhibiting the metal embedded into the inside of the through hole by plating from diffusing into the insulating layer. The present manufacturing method specifically includes the following first forming step, second forming step, removal step and plating step.

(First forming step) A step of forming a first organic film on the wiring inside the through hole formed on the insulating layer on the wiring.

(Second formation step) After forming the first organic film, a step of forming a second organic film on the inner wall surface of the through hole.

(Removal step) A step of removing the first organic film after forming the second organic film.

(Coating step) A step of forming a coating layer inside the through hole after removing the first organic film.

Below, the details of this manufacturing method are described with reference to the drawings.

FIG. 1 is a schematic diagram showing a series of steps for forming an organic film inside a through hole provided on a wiring substrate 10. FIG. 1 shows a partially enlarged view of a through hole 11 and its peripheral portion. FIG. 1 (a) shows the state before an organic film is formed on an inner wall surface 12 using a selective surface modification composition.

As shown in FIG. 1( a ), the wiring substrate 10 includes wiring 13. The wiring 13 is formed of a metal material. The metal constituting the wiring 13 is not particularly limited, and examples thereof include copper, iron, zinc, cobalt, aluminum, titanium, tin, tungsten, zirconium, tantalum, germanium, molybdenum, ruthenium, gold, silver, platinum, palladium, and nickel. Furthermore, the metal contained in the wiring 13 may be a metal element, an alloy, a conductive nitride, a metal oxide, and the like. Among them, the wiring 13 is preferably formed of a conductive material including copper, cobalt, aluminum, tungsten, germanium, ruthenium, gold, silver, platinum or palladium, and more preferably formed of a conductive material including copper (Cu) or cobalt (Co). An insulating layer 14 is provided on the wiring 13 and adjacent to the wiring 13.

The insulating layer 14 is formed of a silicon-containing material. The insulating layer 14 preferably has at least one group selected from the group consisting of hydrogen atoms, hydroxyl groups, pendant oxygen groups, and -N(R ¹ ) ₂ (wherein R ¹ is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. The same shall apply hereinafter) bonded to silicon atoms on its surface (hereinafter also referred to as "silicon-containing group"). Specific examples of silicon-containing groups include Si-H, Si-OH (silanol group), Si=O, Si-N(R ¹ ) ₂ , etc. Examples of the material constituting the insulating layer 14 include semiconductor materials such as silicon oxide, silicon nitride, and silicon oxynitride (SiO ₂ , SiOC, Si ₃ N ₄ , SiNx, and SiON).

A through hole 11 is provided on the insulating layer 14. The through hole 11 is formed on the insulating layer 14 in a manner that penetrates the insulating layer 14 in the thickness direction. Thus, the wiring 13 is exposed at the bottom 15 inside the through hole. Furthermore, the method for forming the through hole 11 on the insulating layer 14 is not particularly limited, and for example, a previously known method such as dry etching can be appropriately adopted.

It is preferred that the wiring substrate 10 that is plated and embedded by the present manufacturing method is subjected to a treatment (substrate modification step) for surface modification of the wiring substrate 10 (more specifically, surface modification of the insulating layer 14). The substrate modification treatment may be dry or wet. In the case of dry treatment, the substrate modification treatment in the present manufacturing method is preferably an ashing treatment using _N2 / _H2 gas or _O2 gas. In the case of a wet process, from the viewpoint of improving the coating and adhesion of the selective surface modification composition, a substrate modification treatment preferably involves contact with a treatment solution containing tetramethyl ammonium hydroxide (TMAH), hydrogen fluoride (HF), ammonia (NH ₃ ), tetramethyl ammonium fluoride (TMAF), or citric acid.

<First formation step>

In the present manufacturing method, in the first forming step, the first organic film 16 is first formed on the wiring 13 exposed at the bottom 15 of the through hole 11 (see (b) in FIG. 1 ). The first organic film 16 is a film covering the wiring 13, and is formed directly on the wiring 13 using a composition (hereinafter, also referred to as the "first composition") including a compound (A) as a main component of the film and a solvent. Specifically, it is preferred to form the first organic film 16 on the bottom 15 by a method including the following steps 1A and 2A.

(Step 1A) A step of applying the first component to the surface of the wiring substrate 10.

(Step 2A) A step of removing the solvent from the first component applied on the surface of the substrate.

． Step 1A: Painting step

In this step, the composition is applied to the surface of at least the bottom 15 of the wiring substrate 10. Examples of methods for applying the composition include spraying, roller coating, spin coating, slit die coating, rod coating, inkjet, etc. Among these, it is preferred to apply the composition by spin coating, slit die coating, or rod coating.

The surface of the substrate coated with the composition may be subjected to a pre-treatment such as plasma treatment using _H2 , a mixed gas of _N2 and _H2 , _O2 gas, or a wet modification treatment for hydrophilizing the substrate surface. In order to improve the coating property and fully promote the surface modification using the composition, it is preferred to perform plasma treatment on the surface of the substrate coated with the composition so that at least one of Si-OH, Si-H and Si-N is fully generated on the coated surface of the composition.

．Step 2A: Solvent removal step

In this step, it is preferred to perform a heat treatment to remove the solvent from the composition applied on the surface of the substrate. In this way, a first organic film 16 is formed on the surface of the wiring 13, and the surface of the wiring 13 exposed to the bottom 15 inside the through hole is selectively modified by the compound (A). The heat treatment can be performed using a heating device such as an oven or a heating plate. When performing the heat treatment, the heating temperature also depends on the type of solvent, and is preferably above 50°C, more preferably above 80°C, and further preferably above 100°C. In addition, the heating temperature is preferably below 250°C, and more preferably below 200°C. The heating time is preferably 0.5 minutes to 30 minutes, and more preferably 1 minute to 20 minutes. The thickness of the formed first organic film 16 is, for example, 1nm~10nm, preferably 1nm~5nm, and more preferably 1nm~3nm.

Furthermore, in order to remove the unadsorbed compound (A), etc., the surface of the substrate formed with the first organic film 16 may be subjected to a rinsing treatment such as washing with an organic solvent or washing with running water. Examples of organic solvents used as rinsing liquids include propylene glycol monomethyl ether acetate, isopropyl alcohol, acetone, methyl ethyl ketone, methyl n-propyl ketone, and a mixed solvent of two or more of these.

<Second formation step>

In the next second forming step, after the first organic film 16 is formed on the bottom 15 by the first forming step, the second organic film 17 is formed on the inner wall surface 12 (refer to FIG. 1 (c) and FIG. 1 (d)). The second organic film 17 is formed using a polymer composition including a polymer and a solvent. Specifically, it is preferred to form the second organic film 17 by a method including the following steps 1B and 2B.

(Step 1B) A step of applying a polymer composition to the surface of the wiring substrate 10.

(Step 2B) A step of removing the solvent from the polymer composition applied on the surface of the substrate.

． Step 1B: Painting step

In this step, a polymer composition is applied to at least the inner surface of the through hole 11 in the wiring substrate 10. The method of applying the polymer composition is not particularly limited, and for example, the method illustrated in step 1A can be used.

．Step 2B: Solvent removal step

In this step, it is preferred to perform a heat treatment to remove the solvent from the polymer composition applied to the surface of the substrate. Thereby, a second organic film 17 is directly formed on the inner wall surface 12, and the surface of the inner wall surface 12 inside the through hole is selectively modified. The heat treatment can be performed, for example, using a heating device such as an oven or a heating plate. In the heat treatment, the heating temperature is preferably above 80°C, more preferably above 100°C, and further preferably above 120°C. In addition, the heating temperature is preferably below 300°C, and more preferably below 280°C. The heating time is preferably 0.5 minutes to 30 minutes, and more preferably 1 minute to 20 minutes. The thickness of the formed second organic film 17 is, for example, 1nm to 50nm, preferably 1nm to 5nm, and more preferably 1nm to 3nm.

Furthermore, in order to remove the unadsorbed polymer, etc., the surface of the substrate on which the organic film is formed may be rinsed with an organic solvent or running water. Examples of organic solvents used as rinsing liquids include propylene glycol monomethyl ether acetate, isopropyl alcohol, acetone, methyl ethyl ketone, methyl n-propyl ketone, and mixed solvents of two or more of these.

The second organic film 17 has a functional group (hereinafter also referred to as "functional group FM") that can form a bond with a metal contained in the coating layer 18 (refer to (f) of FIG. 1) formed inside the through hole by the coating step described later. The functional group FM is preferably a functional group that can form a coordination bond with a metal element, for example, a carboxyl group, a sulfide group, a dithiocarbonyl group (-C(=S)-S-), a thiocarbamate group (-NR ²⁰ -C(=O)-S-), a thioamide group (-C(=S)-NR ²⁰ -), etc. In addition, the functional group FM is equivalent to the "second functional group". R ²⁰ represents a hydrogen atom or a monovalent group. As a specific example of the case where R ²⁰ is a monovalent group, a monovalent hydrocarbon group having 1 to 10 carbon atoms can be cited.

One form of the second organic film 17 is a multilayer structure. Specifically, as shown in FIG. 1(c) and FIG. 1(d), the second organic film 17 is a laminated film of a first layer 17a formed on the inner wall surface 12 and a second layer 17b formed on the first layer 17a. The first layer 17a is selectively formed on the inner wall surface 12 (see FIG. 1(c)) using a composition (hereinafter also referred to as "second composition") containing a polymer (I) and a solvent, wherein the polymer (I) has a functional group (hereinafter also referred to as "functional group F1") that can interact with a group on the surface of the insulating layer 14. In addition, the second layer 17b is selectively formed on the first layer 17a using a composition containing polymer (II) and a solvent (hereinafter also referred to as the "third composition") (refer to (d) of Figure 1). At this time, the formation of the second organic film 17 (first layer 17a and second layer 17b) on the surface of the first organic film 16 is hindered.

Furthermore, when forming a laminated film including a first layer 17a and a second layer 17b on the inner wall surface 12, it can be performed as follows: first, the first layer 17a is formed by steps 1B and 2B using the second component, and then steps 1B and 2B are performed again using the third component to form the second layer 17b.

When the second organic film 17 is a multi-layer structure, the following methods can be cited as methods for obtaining the second organic film 17 having the functional group FM: a method of using a polymer having the functional group FM or a functional group that generates the functional group FM by heat (hereinafter also referred to as "functional group FP") as polymer (I); a method of using a polymer having the functional group FM or the functional group FP as polymer (II); a method of generating the functional group FM by the reaction of the functional group of polymer (I) with the functional group of polymer (II) during film formation, etc.

Another form of the second organic film 17 is a single-layer structure. When the second organic film 17 is a single-layer film, the second organic film 17 is formed using a polymer (I) having a functional group F1 that can interact with a base (containing a silicon group) on the surface of the insulating layer 14. In this case, the second organic film 17 is preferably formed on the inner wall surface 12 by using a composition (hereinafter also referred to as "polymer (III)") and a solvent, and performing the steps 1B and 2B, wherein the polymer (III) has a functional group F1, and a functional group FM that can form a bond with the metal contained in the coating layer 18 or a functional group FP that generates the functional group FM by heat.

<Removal steps>

In this step, after the second organic film 17 is formed on the inner wall surface 12, the first organic film 16 is removed while the second organic film 17 remains (see (e) in FIG. 1 ). The method of removing the first organic film 16 is not particularly limited, and for example, a method of contacting the first organic film 16 with a treatment agent can be listed. The treatment agent preferably contains an organic acid. Examples of the organic acid include acetic acid, citric acid, apple acid, 2-ethylhexanoic acid, and the like.

In the removal step, when the first organic film 16 is brought into contact with an organic acid to dissolve and remove the first organic film 16, a step of bringing the surface of the through hole 11 into contact with an alkali (alkali treatment step) may be further included after the first organic film 16 is brought into contact with the organic acid. In this way, the residue of the first organic film 16 on the surface of the through hole can be minimized, and when the metal is buried in the through hole by the plating step described later, the metal can be buried well, which is preferable in this respect. Examples of the base used include organic bases such as triethylamine, 4-dimethylaminopyridine (DMAP), pyridine, tetramethylammonium hydroxide, aqueous ammonia solution, aqueous hydrazine solution, and inorganic bases such as sodium hydride, K ₂ CO ₃ , and Cs ₂ CO _3. Among them, organic bases are more preferred.

<Application steps>

In the present manufacturing method, after the first organic film 16 is removed to expose the wiring 13 to the bottom 15, a plating process is then performed with the organic film 17 remaining, thereby forming a plating layer 18 as a metal layer inside the through hole (see (f) of FIG. 1 ). The plating method is not particularly limited, and known electrolytic plating, electroless plating, melt plating, vacuum plating, vapor phase plating, etc. may be used. When applied to a semiconductor manufacturing step, electrolytic plating or electroless plating is preferably used, and electroless plating is particularly preferred. Specifically, a method can be cited in which the wiring 13 exposed to the bottom 15 is used as a catalyst to form an electroless plating layer from the bottom 15 upward. Furthermore, after the plating process, the substrate surface can be flattened as needed.

The metal contained in the coating layer 18 is not particularly limited, and for example, the same metal as the metal exemplified as the constituent material of the wiring 13 can be cited. Among these, the coating layer 18 preferably contains Cu or Co.

There are few gaps or seams on the coating layer 18 formed in the above manner, so a multi-layer wiring board with high reliability can be produced.

Next, the selective modification composition (first composition, second composition, third composition and fourth composition) used in the present manufacturing method is described. Furthermore, as for each component constituting the composition, unless otherwise specified, one kind may be used alone or two or more kinds may be used in combination.

<First component>

The first component is used to form the first organic film 16 provided on the bottom 15 of the through hole 11. The first component preferably includes a compound (hereinafter also referred to as "compound (A)") having a functional group (hereinafter also referred to as "functional group FS") that can form a bond with the metal included in the wiring 13. The type of bonding between the functional group FS and the metal is not particularly limited, and examples thereof include covalent bonding, ionic bonding, and coordination bonding. Among these, coordination bonding is preferred in terms of the strong bonding force between the wiring 13 and the compound (A). Specifically, the functional group FS is preferably a functional group that can coordinately bond with the metal contained in the wiring 13, and is particularly preferably at least one selected from the group consisting of cyano, boric acid, phosphoric acid, phosphonic acid, phosphate, phosphonate, thiol, disulfide, and a group containing a carbon-carbon unsaturated bond.

Compound (A) may be a low molecular compound or a polymer. Here, the so-called "low molecular compound" in this specification is a compound that does not show molecular weight distribution, and is different from a polymer in this respect. When compound (A) is a low molecular compound, from the perspective of improving the hydrophobicity of the self-organized membrane and improving the matrix selectivity of the second organic membrane 17, compound (A) preferably has a carbon number of 6 or more, and more preferably has a carbon number of 12 or more. In addition, when compound (A) is a low molecular compound, the carbon number is preferably 50 or less, and more preferably 40 or less.

Specific examples of compound (A) being a low molecular weight compound include: capronitrile, octanonitrile, decanenitrile, dodecanenitrile, tetradecanenitrile, and compounds represented by the following formulas (a-1) to (a-5), etc.

When compound (A) is a polymer, the main skeleton of the polymer (hereinafter, also referred to as "polymer (A)") is not particularly limited. As a monomer constituting polymer (A), a monomer having an unsaturated carbon-carbon bond of the polymer can be preferably used. As specific examples of the monomer, for example, at least one monomer selected from the group consisting of (meth) alkyl esters, (meth) acrylates having an alicyclic structure, (meth) acrylates having an aromatic ring structure, aromatic vinyl compounds, N-substituted maleimide compounds, vinyl compounds having a heterocyclic structure, conjugated diene compounds, nitrogen-containing vinyl compounds, alkenes, vinyl cycloalkanes, cycloalkenes, and unsaturated dicarboxylic acid dialkyl ester compounds can be listed. Furthermore, in this specification, "(meth)acryl" means including acryl and methacryl. "(meth)acrylic acid" means including acrylic acid and methacrylic acid.

Specific examples of the monomer include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-lauryl (meth)acrylate, n-stearyl (meth)acrylate, and the like. Specific examples of the monomer include alkyl (meth)acrylate, such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-lauryl (meth)acrylate, and n-stearyl (meth)acrylate. Specific examples of the monomer include cyclohexyl (meth)acrylate, 2-methylcyclohexyl (meth)acrylate, tricyclo[5.2.1.0 ^2,6 ]decane-8-yl (meth)acrylate, tricyclo[5.2.1.0 ^2,5 ] decane-8-yloxyethyl ester, isobornyl (meth)acrylate, etc.; as the (meth)acrylate having an aromatic ring structure, phenyl (meth)acrylate, benzyl (meth)acrylate, etc. can be listed; as the aromatic vinyl compound, styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, α-methylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 5-tert-butyl-2-methylstyrene, divinylbenzene, trivinylbenzene, tert-butoxystyrene, vinylbenzyldimethylamine, (4-vinylbenzyl)dimethylaminoethyl ether, N,N-dimethylaminoethylstyrene, N,N-dimethylaminomethylstyrene, 2-ethyl Styrene, 3-ethylstyrene, 4-ethylstyrene, 2-tert-butylstyrene, 3-tert-butylstyrene, 4-tert-butylstyrene, diphenylethylene, vinylnaphthalene, etc.; as N-substituted maleimide compounds, there can be listed: N-cyclohexylmaleimide, N-cyclopentylmaleimide, N-(2-methylcyclohexyl)maleimide, N-(4-methylcyclohexyl)maleimide, N-(4-ethylcyclohexyl)maleimide, N-(2,6-dimethylcyclohexyl)maleimide, N-norbornylmaleimide, N-tricyclodecylmaleimide, N-adamantylmaleimide, N-phenylmaleimide, N-(2-methylphenyl)maleimide, N-(4- The vinyl compounds having a heterocyclic structure include tetrahydrofurfuryl (meth)acrylate, tetrahydropyranyl (meth)acrylate, 5-ethyl-1,3-dioxane-5-ylmethyl (meth)acrylate, 5-methyl-1,3-dioxane-5-ylmethyl (meth)acrylate, methyl (2-methyl-2-ethyl-1,3-dioxacyclopentane-4-yl)methyl (meth)acrylate, 2-(meth)acryloyloxymethyl-1,4,6-trioxaspiro[4,6]undecane, and 1,4,6-trioxaspiro[4,6]undecane. (γ-butyrolactone-2-yl) ester, (meth) glyceryl carbonate, (meth) acrylate (γ-lactam-2-yl) ester, N-(meth) acrylate oxyethyl hexahydrophthalimide, N-vinyl-2-pyrrolidone, vinyl pyridine, etc.; as the covalent diene compound, 1,3-butadiene, isoprene, etc. can be listed; as the nitrogen-containing Examples of vinyl compounds include 2-(dimethylamino)ethyl (meth)acrylate, olefins include propylene, butene, pentene, etc., vinylcycloalkanes include vinylcyclopentane, vinylcyclohexane, etc., cycloolefins include cyclopentene, cyclohexene, etc., and unsaturated dicarboxylic acid dialkyl ester compounds include diethyl itaconate, etc.

As the monomer constituting the polymer (A), the monomer is preferably at least one selected from the group consisting of (meth) alkyl acrylate, (meth) acrylate having an alicyclic structure, (meth) acrylate having an aromatic ring structure, aromatic vinyl compound, conjugated diene compound, olefin, vinyl cycloalkane, and cycloolefin.

The polymer (A) preferably contains a structural unit derived from a monomer having an aromatic ring. In this case, it is preferable in terms of being able to form an organic film with high heat resistance. As a monomer having an aromatic ring, a monomer having an aromatic ring can be arbitrarily selected from the monomers exemplified above, among which an aromatic vinyl compound can be preferably used. Furthermore, in the monomer having an aromatic ring, the aromatic ring may have a substituent. As a substituent, for example: a monovalent hydrocarbon group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a halogen atom, etc. can be listed.

In polymer (A), the proportion of structural units derived from monomers having an aromatic ring relative to all structural units contained in polymer (A) is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 50 mol% or more.

The polymer (A) may have a functional group FS on either the main chain or the side chain. In terms of improving substrate selectivity and forming an organic film with a sufficient film thickness relative to the substrate (wiring 13), the polymer (A) preferably has a functional group FS at the end of the main chain, and more preferably has a functional group FS at a single end of the polymer chain.

The method for obtaining the polymer (A) having the functional group FS at the main chain terminal is not particularly limited, and can be appropriately selected according to the type of functional group FS to be introduced. For example, there can be listed: a method of reacting the active terminal of the polymer obtained by anionic polymerization with a terminal treatment agent having the functional group FS; a method of reacting the active terminal of the polymer with a terminal treatment agent capable of generating the functional group FS to introduce a structure capable of generating the functional group FS into the terminal of the polymer, and then performing a treatment for generating the functional group FS (e.g., deprotection) to generate the functional group FS; a method of reacting the active terminal of the polymer with a terminal treatment agent having the functional group FG to introduce the functional group FG into the terminal of the polymer, and then reacting a compound having a functional group capable of reacting with the functional group FG and the functional group FS with the functional group FG introduced into the polymer, etc.

The method for synthesizing polymer (A) is not particularly limited. For example, when polymer (A) is obtained by polymerizing a monomer having polymer unsaturated carbon-carbon bonds, the monomer can be used in an appropriate solvent and in the presence of a polymerization initiator, etc., according to a known method such as free radical polymerization and anionic polymerization to produce polymer (A). The form of polymerization used to obtain polymer (A) is not particularly limited, and random polymerization, block (co)polymerization, etc. can be listed.

In the case of obtaining a polymer having a functional group FS at the end of the main chain, it is preferably to use anionic polymerization. In the case of anionic polymerization, as polymerization initiators, alkali metal compounds such as n-butyl lithium, sec-butyl lithium, tert-butyl lithium, etc. can be listed. The amount of polymerization initiator used is, for example, 0.001 mol to 1 mol relative to the total amount of monomers used in the reaction. As polymerization solvents, for example, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, etc. can be listed. The amount of polymerization solvent used is preferably set to an amount of 1 mass% to 60 mass% relative to the total amount of the monomers used in the reaction relative to the total amount of the reaction solution.

In the polymerization, the reaction temperature is, for example, -100°C to 120°C. The reaction time varies depending on the type of polymerization initiator and monomer or the reaction temperature, and is generally 0.1 hour to 10 hours. The polymer obtained by the reaction can be directly used in the preparation of the composition while being dissolved in the reaction solution, or can be used in the preparation of the composition after being separated from the reaction solution. The separation of the polymer can be carried out by, for example, a method of injecting the reaction solution into a large amount of a poor solvent and drying the precipitate obtained under reduced pressure, a method of removing the reaction solution by reduced pressure distillation using an evaporator, and other known separation methods.

For polymer (A), the weight average molecular weight (Mw) of polystyrene conversion obtained by gel permeation chromatography (GPC) is preferably 1,000 or more. If Mw is 1,000 or more, an organic film with sufficiently high heat resistance or chemical resistance can be obtained, which is better in the above aspects. Mw is more preferably 2,000 or more, and more preferably 3,000 or more. In addition, from the perspective of making film-forming properties good, Mw is preferably 10,000 or less, more preferably 9,000 or less, and more preferably 8,000 or less. The molecular weight distribution (Mw/Mn) represented by the ratio of the weight average molecular weight Mw to the number average molecular weight Mn is preferably 4.0 or less, more preferably 3.0 or less, and more preferably 2.5 or less.

The first component is preferably a liquid component obtained by dissolving or dispersing the compound (A) in a solvent. The solvent is preferably an organic solvent that can dissolve the compound (A) and does not react with the components. Examples of the solvent used in the preparation of the first component include alcohol solvents, ether solvents, ketone solvents, amide solvents, ester solvents, hydrocarbon solvents, etc.

The amount of compound (A) contained in the first component is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and further preferably 0.5% by mass or more relative to the total amount of compound (A) and solvent. If the content of compound (A) is 0.1% by mass or more, the surface modification of wiring 13 can be fully performed by compound (A), and the adhesion of the second component can be suppressed, which is better in the above aspect. In addition, relative to the total amount of compound (A) and solvent, the content of compound (A) is preferably 30% by mass or less, more preferably 20% by mass or less, and further preferably 10% by mass or less. If the content of compound (A) is 30% by mass or less, the film thickness of the first organic film 16 will not become too large, and the viscosity of the first component will not become too high, which can ensure good coating properties.

<Second component>

Next, the components contained in the second component and other components prepared as needed are described. The second component is a polymer composition used to form the first layer 17a on the inner wall surface 12 of the through hole 11. The second component contains a polymer (I) and a solvent, and the polymer (I) has a functional group (functional group F1) that can interact with the base of the insulating layer 14 on the surface. Furthermore, the functional group F1 is equivalent to the "first functional group". In this specification, the so-called "interaction" refers to the formation of chemical bonds between molecules, or the action of physical forces between molecules, also known as "adsorption". In addition to covalent bonding, ionic bonding and metal bonding, the interaction also includes coordination bonding, hydrogen bonding and van der Waals force.

〔Polymer (I)〕

． Functional group F1

The functional group F1 possessed by the polymer (I) is preferably a functional group that selectively interacts (adsorbs) with a group (including a silyl group) formed by bonding to a silicon atom and at least one selected from the group consisting of a hydrogen atom, a hydroxyl group, a pendoxy group, and -N(R ¹ ) _2. More specifically, the functional group F1 is preferably at least one selected from the group consisting of a silanol group, an alkoxysilyl group, -N(Si(R ⁵ ) ₃ ) ₂ , an amino group, a hydroxyl group, and a conjugated nitrogen-containing heterocyclic group. Here, R ⁵ is independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms.

When the functional group F1 is a group "-N(Si( ^R5 ) ₃ ) ₂ ", as the monovalent organic group having 1 to 10 carbon atoms in ^R5 , a monovalent hydrocarbon group having 1 to 10 carbon atoms can be listed. The conjugated nitrogen-containing heterocyclic group is a group having a conjugated nitrogen-containing heterocyclic ring, and specifically, groups having a ring structure such as a carbazole ring, a benzocarbazole ring, a dibenzocarbazole ring, an indole ring, a pyrrole ring, an imidazole ring, a pyridine ring, a triazole ring, and a triazine ring can be listed. Furthermore, the conjugated nitrogen-containing heterocyclic group may have a substituent in the heterocyclic portion. As the substituent, for example, an alkyl group having 1 to 5 carbon atoms, a halogen atom, etc. can be listed.

In terms of high affinity with the silicon-containing group on the surface of the insulating layer 14 and good storage stability of the second component, the functional group F1 is preferably at least one selected from the group consisting of a silanol group, an alkoxysilyl group, and a conjugated nitrogen-containing heterocyclic group. In terms of showing selective adsorption to silicon oxide and further improving the adhesion between the first layer 17a and the insulating layer 14, it is further preferably an alkoxysilyl group.

． Cross-linking groups

The polymer (I) preferably has a crosslinking group. Here, the "crosslinking group" in this specification refers to a group that forms a covalent bond by reacting the same or different functional groups with each other by thermal endowment or the like. By having a crosslinking group in the polymer (I), an organic film with high heat resistance and insulation damage resistance can be formed, which is preferred in the above aspect. In addition, the crosslinking structure between the first layer 17a and the second layer 17b can be formed by utilizing the crosslinking property of the polymer (I), thereby improving the adhesion of the second organic film 17. As cross-linking groups, for example, there can be listed: groups having carbon-carbon unsaturated bonds, groups having a condensed ring structure of an aromatic ring and a cyclobutane ring, cyclic ether groups, cyclic carbonate groups, acid anhydride groups, carboxyl groups, protected carboxyl groups, etc.

Specific examples of the crosslinking group include, as a group having a carbon-carbon unsaturated bond, for example, a vinyl group, a vinyloxy group, an allyl group, a (meth)acryloyl group, a vinylphenyl group, etc.; as a group having a condensed ring structure of an aromatic ring and a cyclobutane ring, for example, a group having a condensed ring structure of a cyclobutane ring and a benzene ring, a group having a condensed ring structure of a cyclobutane ring and a naphthyl ring, etc.; as a cyclic ether group, for example, an oxycyclopropyl group, an oxycyclobutyl group, etc.; as a protected carboxyl group, for example, the group "-COOR ⁹ " (wherein R ⁹ is a thermally dissociable group), etc.

Specific examples of the group "-COOR ⁹ " include, for example, the structure represented by the following formula (X-1), the acetal ester structure of carboxylic acid, the ketal structure of carboxylic acid, and the like.

(In formula (X-1), ^R6 , ^R7 and ^R8 are (1) or (2) below. (1) ^R6 , ^R7 and ^R8 are each independently an alkyl group having 1 to 10 carbon atoms or a monovalent alicyclic alkyl group having 3 to 20 carbon atoms. (2) ^R6 and ^R7 are mutually bonded and together with the carbon atoms to which ^R6 and ^R7 are bonded, form an alicyclic alkyl structure or a cyclic ether structure having 4 to 20 carbon atoms. ^R8 is an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms. "*" indicates a bonding bond)

Specific examples of the structure represented by the formula (X-1) include tert-butyloxycarbonyl, 1-cyclopentylethoxycarbonyl, 1-cyclohexylethoxycarbonyl, 1-norbornylethoxycarbonyl, 1-phenylethoxycarbonyl, 1-(1-naphthyl)ethoxycarbonyl, 1-benzylethoxycarbonyl, 1-phenylethylethoxycarbonyl, etc.

Specific examples of the acetal ester structure of carboxylic acid include: 1-methoxyethoxycarbonyl, 1-ethoxyethoxycarbonyl, 1-propoxyethoxycarbonyl, 1-butoxyethoxycarbonyl, 1-cyclohexyloxyethoxycarbonyl, 2-tetrahydropyranyloxycarbonyl, 1-phenoxyethoxycarbonyl, 2-tetrahydrofuranyloxycarbonyl, etc.

Specific examples of the ketal ester structure of carboxylic acid include: 1-methyl-1-methoxyethoxycarbonyl, 1-methyl-1-ethoxyethoxycarbonyl, 1-methyl-1-propoxyethoxycarbonyl, 1-methyl-1-butoxyethoxycarbonyl, 1-methyl-1-cyclohexyloxyethoxycarbonyl, 2-(2-methyltetrahydrofuranyl)oxycarbonyl, 2-(2-methyltetrahydropyranyl)oxycarbonyl, 1-methoxycyclopentyloxycarbonyl, 1-methoxycyclohexyloxycarbonyl, etc.

Among these, the functional group FM is generated by heat (specifically, heating during film formation), thereby improving the adhesion with the metal contained in the coating layer 18. The crosslinking group possessed by the polymer (I) is particularly preferably at least one selected from the group consisting of anhydride groups and protected carboxyl groups.

The main skeleton of polymer (I) is not particularly limited. In terms of excellent heat resistance, high freedom of monomer selection, and relatively easy introduction of functional group F1, polymer (I) is preferably a polymer obtained by using a monomer having a polymerizable carbon-carbon unsaturated bond. Polymer (I) preferably contains a structural unit having functional group F1 (hereinafter, also referred to as "structural unit U1"), and more preferably contains a structural unit having a crosslinking group (hereinafter, also referred to as "structural unit U2").

Regarding the monomers providing the structural unit U1, examples of the monomers having a silanol group include dimethoxyhydroxysilylstyrene, diethoxyhydroxysilylstyrene, dimethylhydroxysilylstyrene, and diethylhydroxystyrene. Examples of the monomers having an alkoxysilyl group include 4-dimethylmethoxysilylstyrene, 4-diethylmethoxystyrene, 4-methylethylmethoxysilylstyrene, 3-(meth)acryloxypropyldimethylmethoxystyrene, and 3-(meth)acryloxypropyldiethylmethoxystyrene. Examples of the monomers having a group "-N(Si(R ⁵ ) ₃ ) ₂ " as a monomer, there can be listed compounds represented by the following formula (UA-1) to (UA-3) respectively; as a monomer having an amino group, there can be listed: (meth) acrylate aminomethyl, (meth) acrylate 2-aminoethyl, (meth) acrylate 3-aminopropyl, etc.; as a monomer having a hydroxyl group, there can be listed: (meth) acrylate 2-hydroxyethyl, (meth) acrylate 2-hydroxypropyl, (meth) acrylate 3-hydroxypropyl, (meth) acrylate 4-hydroxybutyl, etc.; as a monomer having a conjugated nitrogen-containing heterocyclic group, there can be listed: N-vinyl carbazole, N-vinylbenzocarbazole, N-vinyldibenzocarbazole, 2-fluoro-9-vinyl carbazole, 2-nitro-9-vinyl carbazole, 2-methoxy-9-vinyl carbazole, etc.

In polymer (I), the content of structural unit U1 is preferably 1 mol% or more, more preferably 2 mol% or more, and further preferably 5 mol% or more, relative to all structural units constituting polymer (I). By setting the content of structural unit U1 to 1 mol% or more, the adhesion between the second organic film 17 and the insulating layer 14 can be sufficiently improved, which is preferable in the above aspect. In addition, from the perspective of ensuring good substrate selectivity, the content of structural unit U1 is preferably 30 mol% or less, more preferably 25 mol% or less, and further preferably 20 mol% or less, relative to all structural units constituting polymer (I). If the content of the structural unit U1 is within the above range, the functional group F1 can be uniformly introduced into the polymer (I), the unevenness of the functional group F1 in the coating film can be suppressed, and it can also be used as a permanent film, which is preferable in the above aspect.

As the structural unit U2, the structural units represented by the following formulas (U2-1) to (U2-4) can be listed.

(In formula (U2-2) to formula (U2-4), ^RA is a hydrogen atom, a monovalent alkyl group having 1 to 5 carbon atoms, a halogen atom, or a halogenated alkyl group having 1 to 5 carbon atoms. ^R9 is a thermally dissociable group. ^R11 is a monovalent alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a halogenated atom. d is an integer of 0 to 4. When d is 2 or more, multiple ^R11s are the same or different)

When the polymer (I) includes the structural unit U2, the content of the structural unit U2 is preferably 5 mol% or more, more preferably 10 mol% or more, and further preferably 20 mol% or more relative to all the structural units constituting the polymer (I). By setting the content of the structural unit U2 to 5 mol% or more, the cross-linked structure can be fully introduced into the second organic film 17, and the insulation damage resistance can be improved, which is better in the above aspect. In addition, from the perspective of ensuring the toughness of the second organic film 17, the content of the structural unit U2 is preferably 70 mol% or less, and more preferably 60 mol% or less relative to all the structural units constituting the polymer (I).

Among the above, the polymer (I) is preferably a polymer having a functional group F1 and at least one cross-linking group selected from the group consisting of anhydride groups and protected carboxyl groups, and as a structural unit containing the functional group F1, it is particularly preferred to contain a structural unit represented by the following formula (1) (hereinafter, also referred to as "structural unit U3").

(In formula (1), R is a hydrogen atom, a monovalent alkyl group having 1 to 5 carbon atoms, a halogen atom, or a halogenated alkyl group having 1 to 5 carbon atoms. ^R2 is a monovalent alkyl group having 1 to 5 carbon atoms. ^R3 is an alkoxy group having 1 to 5 carbon atoms. ^R10 is a monovalent alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a halogenated atom. a is an integer of 0 to 2, and b is an integer of 1 to 3. Wherein a+b=3. c is an integer of 0 to 4. When a is 2, multiple ^R2s are the same or different. When b is 2 or 3, multiple ^R3s are the same or different. When c is 2 or more, multiple ^R10s are the same or different)

In the formula (1), as the monovalent alkyl group in ^R2 , alkyl and cycloalkyl groups can be listed. Among them, ^R2 is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group. In terms of improving the selectivity with respect to the substrate (more specifically, the insulating layer 14), b is preferably 1 or 2, more preferably 1. c is preferably 0 to 2, more preferably 0.

When the polymer (I) includes the structural unit U3, the content of the structural unit U3 is preferably 1 mol% or more, more preferably 2 mol% or more, and further preferably 5 mol% or more relative to all the structural units constituting the polymer (I). By setting the content of the structural unit U3 to 1 mol% or more, the effect of improving the adhesion between the insulating layer 14 and the second organic film 17 can be improved, which is better in the above aspect. In addition, from the perspective of ensuring good substrate selectivity, the content of the structural unit U3 is preferably 40 mol% or less, and more preferably 30 mol% or less relative to all the structural units constituting the polymer (I).

The polymer (I) may further include a structural unit different from the structural unit U1 to the structural unit U3 (hereinafter, also referred to as "other structural unit U4"). The other structural unit U4 is not particularly limited as long as it can be copolymerized with the structural unit U1. The monomer providing the other structural unit U4 is preferably a monomer having a polymerizable carbon-carbon unsaturated bond. Specifically, for example, at least one monomer selected from the group consisting of (meth) alkyl acrylates, (meth) acrylates having alicyclic structures, (meth) acrylates having aromatic ring structures, aromatic vinyl compounds, N-substituted maleimide compounds, vinyl compounds having heterocyclic structures, conjugated diene compounds, nitrogen-containing vinyl compounds, alkenes, vinyl cycloalkanes, cycloalkenes, and unsaturated dicarboxylic acid dialkyl ester compounds can be listed. As specific examples and preferred examples of these, the same compounds as the monomers exemplified in the description of polymer (A) can be listed. In addition, as a monomer providing other structural unit U4, a monomer having a functional group FM and different from the monomer providing structural unit U2 can be used.

In polymer (I), relative to all structural units constituting polymer (I), the content of other structural units U4 is preferably 80 mol% or less, more preferably 70 mol% or less, and even more preferably 60 mol% or less.

From the viewpoint of obtaining an organic film with high heat resistance, the polymer (I) preferably contains a structural unit derived from a monomer having an aromatic ring (hereinafter, also referred to as "structural unit U5"). The monomer providing the structural unit U5 may be one of the structural units U1 to U4, or two or more. As a specific example of a monomer providing the structural unit U5, a monomer having an aromatic ring may be arbitrarily selected from the monomers exemplified as the monomers providing the structural units U1 to U4. Furthermore, the aromatic ring possessed by the structural unit U5 may have a substituent in the ring portion. As the substituent, for example: a monovalent hydrocarbon group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a halogen atom, etc. can be listed.

In polymer (I), the content of structural unit U5 is preferably 10 mol% or more, more preferably 20 mol% or more, and further preferably 30 mol% or more relative to all structural units contained in polymer (I). In addition, the content of structural unit U5 is preferably 99 mol% or less, more preferably 95 mol% or less, and further preferably 90 mol% or less relative to all structural units contained in polymer (I).

The synthesis method of polymer (I) is not particularly limited, and it can be produced by known polymerization methods such as free radical polymerization and anionic polymerization. Among these, when free radical polymerization is used, the synthesis of polymer (I) can be carried out simply, and the cost of the composition can be reduced, which is preferable in the above aspect. Regarding polymer (I), any polymerization form such as random polymerization and block (co)polymerization can also be applied.

In the case of utilizing free radical polymerization, the polymerization initiator may include: 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(isobutyric acid) dimethyl ester, 2,2'-dimethylazobis(2-methylpropionate) and other azo compounds. The amount of the polymerization initiator used is preferably 0.01 to 30 parts by mass relative to 100 parts by mass of the total amount of monomers used in the reaction. As the polymerization solvent, for example, alcohols, ethers, ketones, esters, hydrocarbons and the like may be listed. The amount of the polymerization solvent used is preferably set to be 0.1% to 60% by mass relative to the total amount of the monomers used in the reaction relative to the total amount of the reaction solution.

In the polymerization, the reaction temperature is usually 30°C to 180°C. The reaction time varies depending on the type of polymerization initiator and monomer or the reaction temperature, and is usually 0.5 hours to 10 hours. The polymer obtained by the reaction can be directly used in the preparation of the composition in a state of being dissolved in the reaction solution, or can be used in the preparation of the composition after being separated from the reaction solution. The separation of the polymer can be carried out by, for example, a method of injecting the reaction solution into a large amount of a poor solvent and drying the precipitate obtained under reduced pressure, a method of removing the reaction solution by reduced pressure distillation using an evaporator, and other known separation methods.

For polymer (I), the weight average molecular weight (Mw) of polystyrene conversion obtained by GPC is preferably 1,000 or more. If Mw is 1,000 or more, an organic film with sufficiently high heat resistance or chemical resistance can be obtained, which is better in terms of the above aspects. Mw is more preferably 2,000 or more, and more preferably 3,000 or more. In addition, from the perspective of making film-forming properties good, the Mw of polymer (I) is preferably 10,000 or less, more preferably 9,000 or less, and more preferably 8,000 or less. The molecular weight distribution (Mw/Mn) represented by the ratio of the weight average molecular weight Mw to the number average molecular weight Mn is preferably 4.0 or less, more preferably 3.0 or less, and more preferably 2.5 or less.

[Solvent]

The second component is preferably a liquid component obtained by dissolving or dispersing the polymer (I) in a solvent. The solvent used in the preparation of the second component is preferably an organic solvent that can dissolve the polymer (I) and does not react with the components. Examples of the organic solvent include alcohol solvents, ether solvents, ketone solvents, amide solvents, ester solvents, hydrocarbon solvents, etc.

Specific examples of these include alcohol-based solvents: aliphatic monohydric alcohol-based solvents with 1 to 18 carbon atoms, such as 4-methyl-2-pentanol and n-hexanol; alicyclic monohydric alcohol-based solvents with 3 to 18 carbon atoms, such as cyclohexanol; polyhydric alcohol-based solvents with 2 to 18 carbon atoms, such as 1,2-propylene glycol; polyhydric alcohol partial ether-based solvents with 3 to 19 carbon atoms, such as propylene glycol monomethyl ether, etc.

As ether solvents, there can be listed: dialkyl ether solvents such as diethyl ether, dipropyl ether, dibutyl ether, diamyl ether, diisoamyl ether, dihexyl ether, and diheptyl ether; Cyclic ether solvents such as tetrahydrofuran and tetrahydropyran; ether solvents containing aromatic rings such as diphenyl ether and anisole (methyl phenyl ether), etc.

As ketone solvents, there can be listed: acetone, methyl ethyl ketone, methyl n-propyl ketone, methyl n-butyl ketone, diethyl ketone, methyl isobutyl ketone, 2-heptanone (methyl n-amyl ketone), ethyl n-butyl ketone, methyl n-hexyl ketone, diisobutyl ketone, trimethyl nonanone and other chain ketone solvents; cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, methyl cyclohexanone and other cyclic ketone solvents; 2,4-pentanedione, acetylacetone, acetophenone, etc.

As amide solvents, there can be listed: cyclic amide solvents such as N,N'-dimethylimidazolidone and N-methylpyrrolidone; chain amide solvents such as N-methylformamide, N,N-dimethylformamide, N,N-diethylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, and N-methylpropionamide, etc.

As ester solvents, there are: monocarboxylic acid ester solvents such as n-butyl acetate and ethyl lactate; polyol carboxylic acid ester solvents such as propylene glycol acetate; polyol partial ether carboxylic acid ester solvents such as propylene glycol monomethyl ether acetate; lactone solvents such as γ-butyrolactone and δ-valerolactone; polycarboxylic acid diester solvents such as diethyl oxalate; carbonate solvents such as dimethyl carbonate, diethyl carbonate, ethyl carbonate, propylene carbonate, etc.

Examples of hydrocarbon solvents include: aliphatic hydrocarbon solvents with carbon numbers of 5 to 12, such as n-pentane and n-hexane; aromatic hydrocarbon solvents with carbon numbers of 6 to 16, such as toluene and xylene, etc.

Among them, the solvent used in the preparation of the second component is preferably at least one selected from the group consisting of alcohol solvents, ether solvents, ketone solvents and ester solvents, and more preferably at least one selected from the group consisting of ketone solvents and ester solvents. Among them, from the viewpoint of solubility, it is preferred that the solvent is a mixed solvent containing a ketone solvent and an ester solvent. In the case where the solvent is a mixed solvent containing a ketone solvent and an ester solvent, specifically, the solvent is particularly preferably a mixed solvent containing at least one selected from the group consisting of acetone, methyl ethyl ketone and methyl n-propyl ketone and propylene glycol monomethyl ether acetate.

When a mixed solvent containing a ketone solvent and an ester solvent is used as the solvent, the ratio (mass ratio) of the ketone solvent (X) and the ester solvent (Y) is not particularly limited. With respect to 100 parts by mass of the total amount of the ketone solvent and the ester solvent (X+Y), it is preferred that the ester solvent (Y) is 20 parts by mass to 95 parts by mass, and more preferably 30 parts by mass to 90 parts by mass.

The amount of polymer (I) contained in the second component is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and further preferably 0.5% by mass or more relative to the total amount of polymer (I) and solvent. If the content of polymer (I) is 0.1% by mass or more, a coating with a sufficiently ensured film thickness can be formed on the inner wall surface 12 of the through hole 11. In addition, the content of polymer (I) is preferably 30% by mass or less, more preferably 20% by mass or less, and further preferably 10% by mass or less relative to the total amount of polymer (I) and solvent. If the content of polymer (I) is 30% by mass or less, the film thickness of the organic film will not become too large, and the viscosity of the second component will not become too high, and good coating properties can be ensured.

[Other ingredients]

In addition to the polymer (I) and the solvent, the second component may contain other components. Examples of other components include: polymers without functional groups F1, surfactants (fluorine-based surfactants, silicone-based surfactants, non-ionic surfactants, etc.), antioxidants, etc. The amount of other components can be appropriately selected according to each component within the range that does not damage the effect of the present invention.

The solid content concentration of the second component (the ratio of the total mass of the components other than the solvent in the composition to the total mass of the composition) can be appropriately set in consideration of viscosity or volatility. The solid content concentration of the second component is preferably in the range of 0.1 mass% to 30 mass%. If the solid content concentration is 0.1 mass% or more, the film thickness of the organic film can be fully ensured, which is better in the above aspect. In addition, if the solid content concentration is 30 mass% or less, the film thickness of the organic film will not become too large, and the viscosity of the second component can be appropriately increased, thereby ensuring good coating properties, which is better in the above aspect. The solid content concentration of the second component is more preferably 0.5 mass% to 20 mass%, and more preferably 0.7 mass% to 10 mass%.

<Third component>

Next, the components contained in the third component and other components prepared as needed are described. The third component is a polymer composition used to form the second layer 17b in the second organic film 17. When the polymer (I) has a crosslinking group, the third component preferably contains a polymer (II) and a solvent, wherein the polymer (II) has a functional group (hereinafter also referred to as "functional group F2") that can form a bond with the crosslinking group of the polymer (I). By setting the second organic film 17 as a laminated film of the first layer 17a and the second layer 17b, a crosslinking structure is formed between the first layer 17a and the second layer 17b, and an organic film with excellent heat resistance and insulation damage resistance can be formed. Furthermore, the functional group F2 is equivalent to the "third functional group".

〔Polymer (II)〕

． Functional group F2

The functional group F2 possessed by the polymer (II) is not particularly limited as long as it can react with the cross-linking group possessed by the polymer (I) to form a bond. In terms of being able to form an organic film with excellent adhesion to the coating layer 18 while maintaining the storage stability of the second component and the third component, the functional group F2 is preferably at least one of an oxazoline group and an epoxy group. In addition, in this specification, "epoxy group" refers to an oxacyclopropyl group and an oxacyclobutyl group.

Among them, it is particularly preferred that the polymer (I) has at least one crosslinking group selected from the group consisting of anhydride groups and protected carboxyl groups, and the functional group F2 is at least one of an oxazoline group and an epoxy group. In this case, the insulation damage resistance of the second organic film 17 can be improved by utilizing the reaction of the crosslinking group possessed by the polymer (I) with the functional group F2 to form a crosslinked structure. In addition, it is believed that by generating an amide group through the reaction of anhydride groups or protected carboxyl groups with oxazoline groups, the insulation damage resistance can be further improved by the interaction of amide bonds. Furthermore, in the case where the polymer (I) has an anhydride group, the carboxyl group generated by the crosslinking reaction can be used to further improve the adhesion with the coating layer 18, which is preferred in terms of the above aspect. The carboxyl group generated by the reaction between the crosslinking group of polymer (I) and the functional group F2 is equivalent to the functional group FM (second functional group).

Furthermore, when the protected carboxyl group is introduced into polymer (I) as a crosslinking group to obtain a second organic membrane 17 having a carboxyl group as a functional group FM, the number of crosslinking groups possessed by polymer (I) can be designed to be greater than the number of functional groups F2 possessed by polymer (II) so that the second organic membrane 17 has a functional group FM after the crosslinking reaction.

The main skeleton of polymer (II) is not particularly limited. In terms of excellent heat resistance, high freedom in the selection of monomers, and relatively easy introduction of functional groups F2, polymer (II) is preferably a polymer obtained using monomers having polymerizable carbon-carbon unsaturated bonds. Polymer (II) preferably contains a structural unit having a functional group F2 (hereinafter, also referred to as "structural unit U6").

Regarding the monomers providing the structural unit U6, examples of the monomers having an epoxy group include: glycidyl (meth)acrylate, 3,4-epoxyepoxyhexyl (meth)acrylate, 3,4-epoxyepoxyhexylmethyl (meth)acrylate, 2-(3,4-epoxyepoxyhexyl) (meth)acrylate ethyl, 3,4-epoxytricyclo[5.2.1.0 ^2,6 ]decyl(meth)acrylate, (3-methyloxycyclobutane-3-yl)(meth)acrylate methyl, 4-glycidylstyrene, 3-glycidylstyrene, (3-ethyloxycyclobutane-3-yl)(meth)acrylate, (oxycyclobutane-3-yl)(meth)acrylate methyl, (3-ethyloxycyclobutane-3-yl)(meth)acrylate methyl, and the like; as the monomer having an oxazoline group, 2-vinyl-2-oxazoline, isopropenyloxazoline, and the like can be cited.

In polymer (II), the content of structural unit U6 is preferably 3 mol% or more, more preferably 5 mol% or more, and further preferably 10 mol% or more relative to all structural units constituting polymer (II). By setting the content of structural unit U6 to 3 mol% or more, the effect of improving the insulation damage resistance and the adhesion with the coating layer 18 can be fully obtained, which is preferable in the above aspects. In addition, from the perspective of ensuring good substrate selectivity, the content of structural unit U6 is preferably 40 mol% or less, more preferably 35 mol% or less, and further preferably 30 mol% or less relative to all structural units constituting polymer (II). If the content of the structural unit U6 is within the above range, the functional group F2 can be uniformly introduced into the polymer (II), which can suppress the unevenness of the functional group F2 in the coating film and can also be used as a permanent film, which is better in terms of the above aspect.

．Other structural units

The polymer (II) may further include a structural unit different from the structural unit U6 (hereinafter, also referred to as "other structural unit U7") together with the structural unit U6. The other structural unit U7 is not particularly limited as long as it can copolymerize with the structural unit U6. The monomer providing the other structural unit U7 is preferably a monomer having a polymerizable carbon-carbon unsaturated bond. Specifically, for example, at least one monomer selected from the group consisting of (meth) alkyl acrylates, (meth) acrylates having an alicyclic structure, (meth) acrylates having an aromatic ring structure, aromatic vinyl compounds, N-substituted maleimide compounds, vinyl compounds having a heterocyclic structure, conjugated diene compounds, nitrogen-containing vinyl compounds, alkenes, vinyl cycloalkanes, cycloalkenes, and unsaturated dicarboxylic acid dialkyl ester compounds can be listed. As specific examples and preferred examples of these, the same compounds as the monomers exemplified in the description of polymer (A) can be listed.

In polymer (II), relative to all structural units constituting polymer (II), the content of other structural units U7 is preferably 97 mol% or less, more preferably 95 mol% or less, and even more preferably 90 mol% or less.

From the viewpoint of obtaining an organic film with high heat resistance, polymer (II) preferably further contains a structural unit derived from a monomer having an aromatic ring (hereinafter, also referred to as "structural unit U8"). The monomer providing structural unit U8 may be one of structural unit U6 and structural unit U7, or may be two or more. As a specific example of a monomer providing structural unit U8, a monomer having an aromatic ring may be arbitrarily selected from the monomers exemplified as monomers providing structural units U6 and structural units U7. In polymer (II), the content of structural unit U8 is preferably 10 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more relative to all structural units contained in polymer (II).

Furthermore, the synthesis method of polymer (II) is not particularly limited, similar to polymer (I) and polymer (A). The details of the synthesis method of polymer (II) are the same as those of polymer (I).

For polymer (II), the weight average molecular weight (Mw) of polystyrene conversion obtained by GPC is preferably 800 or more. If Mw is 800 or more, an organic film with sufficiently high heat resistance or chemical resistance can be obtained, which is better in the above aspects. Mw is more preferably 1,000 or more, and more preferably 1,500 or more. In addition, from the perspective of making film-forming properties good, the Mw of polymer (II) is preferably 8,000 or less, more preferably 7,000 or less, and more preferably 6,000 or less. The molecular weight distribution (Mw/Mn) represented by the ratio of the weight average molecular weight Mw to the number average molecular weight Mn is preferably 4.0 or less, more preferably 3.0 or less, and more preferably 2.5 or less.

[Solvent]

The third component is preferably a liquid composition in which the polymer (II) is dissolved or dispersed in a solvent. The solvent used in the preparation of the third component is preferably an organic solvent that can dissolve the polymer (II) and does not react with the components. Examples of the organic solvent include: alcohol solvents, ether solvents, ketone solvents, amide solvents, ester solvents, hydrocarbon solvents, etc. As specific examples and preferred examples of these solvents, the same compounds as those described as specific examples and preferred examples of solvents that can be used in the preparation of the second component can be listed.

The amount of polymer (II) contained in the third component is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and further preferably 0.5% by mass or more relative to the total amount of polymer (II) and solvent. If the content of polymer (II) is 0.1% by mass or more, a coating film having a sufficiently ensured film thickness can be formed, which is preferred in terms of the above aspect. In addition, the content of polymer (II) is preferably 30% by mass or less, more preferably 20% by mass or less, and further preferably 10% by mass or less relative to the total amount of polymer (II) and solvent. If the content of polymer (II) is 30% by mass or less, the film thickness of the organic film will not become too large, and the viscosity of the third component will not become too high, thereby ensuring good coating properties.

[Other ingredients]

In addition to the polymer (II) and the solvent, the third component may contain other components. Examples of other components include: polymers without functional groups F2, surfactants (fluorine-based surfactants, silicone-based surfactants, non-ionic surfactants, etc.), antioxidants, etc. The amount of other components can be appropriately selected according to each component within the range that does not damage the effect of the present invention.

The solid content concentration of the third component is preferably in the range of 0.1 mass% to 30 mass%. If the solid content concentration is 0.1 mass% or more, the thickness of the organic film can be sufficiently ensured, which is preferable in the above aspect. In addition, if the solid content concentration is 30 mass% or less, the thickness of the organic film will not become too large, and the viscosity of the third component can be appropriately increased, thereby ensuring good coating properties. The solid content concentration of the third component is more preferably 0.5 mass% to 20 mass%, and further preferably 0.7 mass% to 10 mass%.

<Fourth component>

Next, the components contained in the fourth composition and other components prepared as needed are described. The fourth composition contains a polymer (III) and a solvent, wherein the polymer (III) has a functional group F1 that can interact with the base of the insulating layer 14 on the surface layer, and a functional group FM that can form a bond with the metal element contained in the coating layer 18 or a functional group FP that generates a functional group FM by heating.

The main skeleton of polymer (III) is not particularly limited, but preferably a polymer obtained by using a monomer having a polymerizable carbon-carbon unsaturated bond. Specific examples of polymer (III) include: [1] a polymer comprising a structural unit having a functional group F1 and a structural unit having a functional group FM or a functional group FP, [2] a polymer comprising a structural unit having a functional group F1 and having a functional group FM or a functional group FP at the end of the polymer, etc. Furthermore, the synthesis method of polymer (III) is not particularly limited, similar to polymer (I), polymer (II) and polymer (A). For details of the synthesis method of polymer (III), the description of the synthesis method of polymer (I) can be cited.

The polymer (III) preferably comprises a structural unit U1 having a functional group F1 and a structural unit having at least one selected from the group consisting of an anhydride group and a protected carboxyl group. The details of the functional group F1 and the structural unit U1 are the same as the specific examples and preferred examples of the functional group F1 and the structural unit U1 possessed by the polymer (I) contained in the first composition. The anhydride group and the protected carboxyl group are the same as the groups exemplified in the crosslinking groups that the polymer (I) may possess. The details of the structural unit having these groups are the same as the specific examples and preferred examples of the structural unit U2 that the polymer (I) may possess. In addition, the polymer (III) may have a crosslinking group that can form a bond with each other with the same group. In this case, the heat resistance and insulation damage resistance of the second organic film 17 can be improved. The preferred content of each structural unit in polymer (III) is the same as the range described for each structural unit in polymer (I).

In addition to the polymer (III) and the solvent, the fourth component may also contain other components other than the polymer (III) and the solvent. As other components, for example, polymers without functional group F1, thermal acid generators (TAG), surfactants, antioxidants, etc. Specific examples of thermal acid generators include diphenyliodonium nonafluorobutanesulfonate, etc. When a thermal acid generator is contained in the fourth component, from the perspective of obtaining the effect of the thermal acid generator and suppressing the depression when the fourth component is applied to the substrate, the contained amount is preferably less than 10 mol%, and more preferably 1 mol% to 5 mol%, relative to the total amount of the fourth component.

Since the second organic film 17 is a single-layer film, the steps of forming the organic film on the inner wall surface 12 of the through hole 11 can be reduced as much as possible, and the manufacturing process can be simplified. In addition, while further thinning the organic film formed on the inner wall surface 12 of the through hole 11, an organic film with excellent adhesion to the coating layer 18 can be formed on the inner wall surface 12 of the through hole 11.

《Layered film forming kit》

The laminate film forming kit of the present invention (hereinafter also referred to as "film forming kit") is used for pretreatment when forming the coating layer 18 inside the through hole 11 in the manufacturing step of the multi-layer wiring substrate. The kit is not particularly limited in form as long as it contains the polymer (I) and the polymer (II). One form of the film forming kit of the present invention is a kit including a first agent containing the polymer (I) and a second agent containing the polymer (II). In this case, it is preferred that the first agent is the second component and the second agent is the third component.

According to the film forming kit of the present invention, in the wiring forming step of forming multi-layer wiring on the substrate, the second organic film 17 (first layer 17a and second layer 17b) can be selectively formed relative to the inner wall surface 12 of the through hole 11. The second organic film 17 formed on the inner wall surface 12 functions as a barrier layer, which can suppress the diffusion of the metal element buried in the through hole to the insulating layer 14. In addition, according to the method of burying the metal into the inside of the through hole 11 whose side is covered by the second organic film 17 by plating treatment, a plating layer 18 with less voids or seams can be formed. Therefore, according to the film forming kit of the present invention, a highly reliable component can be obtained.

《Composition》

The composition of the present invention is a composition used in the pre-treatment of embedding metal into the inside of the through hole 11 by plating treatment in the manufacturing step of the multi-layer wiring board. The composition contains a polymer and a solvent, and the polymer has a cross-linking group and a functional group F1 as at least one selected from the group consisting of anhydride groups and protected carboxyl groups. The details of the polymer and the solvent are as described above. According to such a composition, an organic film with excellent adhesion to the insulating layer 14 and the plating layer 18 can be formed on the inner wall surface 12 of the through hole 11.

[Implementation example]

The following is a more detailed description using examples, but the present invention is not limited to these examples.

In the following examples and comparative examples, the methods for determining the weight average molecular weight and number average molecular weight of the polymer are as follows.

[Weight average molecular weight and number average molecular weight]

The weight average molecular weight (Mw) and number average molecular weight (Mn) of the polymer were measured by gel permeation chromatography (GPC) using Tosoh's GPC columns (two "G2000HXL", one "G3000HXL" and one "G4000HXL") under the following conditions.

Solvent: Tetrahydrofuran (Wako Pure Chemical Industries, Ltd.)

Flow rate: 1.0mL/min

Sample concentration: 1.0 mass%

Sample injection volume: 100μL

Column temperature: 40℃

Detector: Differential refractometer

Standard material: monodisperse polystyrene

1. Synthesis of polymers

[Synthesis Example 1] Synthesis of polymer (A-1)

After the 500 mL flask reaction container was depressurized and dried, 120 g of tetrahydrofuran that had been distilled and dehydrated was injected under nitrogen atmosphere and cooled to -78°C. Then, 2.38 mL of 1N cyclohexane solution of second butyl lithium (sec-BuLi) was injected into the tetrahydrofuran, and then 13.3 mL of styrene was injected dropwise over 30 minutes. The styrene was subjected to adsorption filtration separation using silica gel and distillation and dehydration treatment to remove polymerization inhibitors. The polymerization system was confirmed to be orange. During the dropwise injection, it was necessary to pay attention that the internal temperature of the reaction solution should not be higher than -60°C. After the dropwise addition, it was aged for 30 minutes. Then, 0.18 ml of N,N-dimethylformamide was injected to terminate the polymerization end. The reaction solution was heated to room temperature, the obtained reaction solution was concentrated, and replaced with methyl isobutyl ketone (MIBK). Then, 1,000 g of 2% oxalic acid aqueous solution was injected and stirred, and the bottom water layer was removed after standing. This operation was repeated three times to remove metallic Li. Then, 1,000 g of ultrapure water was injected and stirred, and the bottom water layer was removed. After repeating this operation three times to remove oxalic acid, the solution was concentrated and added dropwise to 500 g of methanol to precipitate the polymer, and the solid was recovered using a Buchner funnel. The polymer was dried under reduced pressure at 60°C to obtain 11.9 g of a white polymer. The Mw of the obtained polymer was 5000, the Mn was 4800, and the Mw/Mn was 1.04.

Next, 10.0 g of the white polymer was dissolved in 40 g of toluene, and 0.21 g of malononitrile, 0.25 g of ammonium acetate, and 0.038 g of acetic acid were added, and the mixture was heated and dry-distilled for 4 hours in a nitrogen environment. The reaction solution was heated to room temperature, the obtained reaction solution was concentrated, and replaced with methyl isobutyl ketone (MIBK). After that, 500 g of a 2% aqueous solution of sodium bicarbonate was injected and stirred, and the bottom water layer was removed after standing. This operation was repeated three times to remove the metallic Li. After that, 1,000 g of ultrapure water was injected and stirred, and the bottom water layer was removed. After the operation was repeated three times to remove the acetic acid, the solution was concentrated and added dropwise to 500 g of methanol to precipitate the polymer, and the solid was recovered using a Buchner funnel. The obtained polymer was dried under reduced pressure at 60°C to obtain 9.8 g of a white polymer (A-1). The Mw of the polymer (A-1) was 5300, the Mn was 5100, and the Mw/Mn was 1.04.

[Synthesis Example 2] Synthesis of polymer (A-2)

After the 500 mL flask reaction container was depressurized and dried, 120 g of tetrahydrofuran that had been distilled and dehydrated was injected under nitrogen atmosphere and cooled to -78°C. Then, 2.30 mL of 1N cyclohexane solution of second butyl lithium (sec-BuLi) was injected into the tetrahydrofuran, and then 13.3 mL of styrene was dripped over 30 minutes. The styrene was subjected to adsorption filtration separation and distillation and dehydration treatment using silica gel to remove polymerization inhibitors, and the polymerization system was confirmed to be orange. During the dripping and injection, it should be noted that the internal temperature of the reaction solution should not be above -60°C. After the dripping is completed, it is aged for 30 minutes. Then, 0.47 ml of diisopropyl bromoethylborate was injected to terminate the polymerization terminal. The reaction solution was heated to room temperature, the obtained reaction solution was concentrated, and replaced with methyl isobutyl ketone (MIBK). Then, 1,000 g of 2% oxalic acid aqueous solution was injected and stirred, and the bottom water layer was removed after standing. This operation was repeated three times to remove metallic Li. Then, 1,000 g of ultrapure water was injected and stirred, and the bottom water layer was removed. This operation was repeated three times to remove oxalic acid. Then, the solution was concentrated and added dropwise to 500 g of methanol to precipitate the polymer, and the solid was recovered using a Buchner funnel. The polymer was dried under reduced pressure at 60°C to obtain 11.7 g of a white polymer. The Mw of the obtained polymer was 5000, the Mn was 4700, and the Mw/Mn was 1.06.

Next, 0.96 g of triethylamine, 10 g of ultrapure water, 4 g of propylene glycol monomethyl ether, and 40 g of propylene glycol monomethyl ether acetate were added to 10.0 g of the polymer, and heated and stirred at 80°C in a nitrogen environment. The reaction solution was heated to room temperature, the obtained reaction solution was concentrated, and replaced with methyl isobutyl ketone (MIBK). Thereafter, 500 g of a 2% aqueous solution of sodium bicarbonate was injected and stirred, and the bottom water layer was removed after standing. This operation was repeated three times to remove metallic Li. Thereafter, 1,000 g of ultrapure water was injected and stirred, and the bottom water layer was removed. This operation was repeated three times to remove acetic acid. Afterwards, the solution was concentrated and added dropwise to 500 g of methanol to precipitate the polymer, and the solid was recovered using a Buchner funnel. The polymer was dried under reduced pressure at 60°C to obtain 9.8 g of a white polymer (A-2). The Mw of the obtained polymer (A-2) was 5100, the Mn was 4800, and the Mw/Mn was 1.04.

[Synthesis Example 3] Synthesis of polymer (A-3)

After the 500 mL flask reaction container was dried under reduced pressure, 120 g of tetrahydrofuran that had been distilled and dehydrated was injected under nitrogen atmosphere and cooled to -78°C. Then, 2.30 mL of sec-BuLi 1 N cyclohexane solution was injected into the tetrahydrofuran, and then 13.3 mL of styrene that had been subjected to adsorption filtration separation and distillation and dehydration treatment using silica gel to remove polymerization inhibitors was injected dropwise over 30 minutes. The polymerization system was confirmed to be orange. During the dropwise injection, it was necessary to pay attention that the internal temperature of the reaction solution should not be higher than -60°C. After the dropwise injection was completed, the solution was aged for 30 minutes. Then, 0.33 ml of diethyl chlorophosphate was injected to terminate the polymerization terminal reaction. The reaction solution was heated to room temperature, the obtained reaction solution was concentrated, and replaced with methyl isobutyl ketone (MIBK). Then, 1,000 g of 2% aqueous oxalic acid solution was injected and stirred, and the bottom water layer was removed after standing. This operation was repeated three times to remove metallic Li. Then, 1,000 g of ultrapure water was injected and stirred, and the bottom water layer was removed. This operation was repeated three times to remove oxalic acid. Then, the solution was concentrated and added dropwise to 500 g of methanol to precipitate the polymer, and the solid was recovered using a Buchner funnel. The polymer was dried under reduced pressure at 60°C to obtain 11.5 g of a white polymer. The obtained polymer has an Mw of 5100, an Mn of 4900, and an Mw/Mn of 1.04.

Next, 0.81 g of triethylamine, 4 g of propylene glycol monomethyl ether, and 40 g of propylene glycol monomethyl ether acetate were added to 10.0 g of the polymer, and the mixture was heated and stirred at 80°C in a nitrogen environment. The reaction solution was heated to room temperature, the obtained reaction solution was concentrated, and replaced with methyl isobutyl ketone (MIBK). Then, 500 g of a 2% aqueous solution of oxalic acid was injected and stirred, and the bottom water layer was removed after standing. This operation was repeated three times to remove metallic Li. Then, 1,000 g of ultrapure water was injected and stirred, and the bottom water layer was removed. This operation was repeated three times to remove acetic acid. Afterwards, the solution was concentrated and added dropwise to 500 g of methanol to precipitate the polymer, and the solid was recovered using a Buchner funnel. The polymer was dried under reduced pressure at 60°C to obtain 9.2 g of a white polymer (A-3). The Mw of the obtained polymer (A-3) was 5100, the Mn was 4800, and the Mw/Mn was 1.06.

[Synthesis Example 4] Synthesis of polymer (A-4)

After the 500 mL flask reaction container was depressurized and dried, 120 g of tetrahydrofuran that had been distilled and dehydrated was injected under nitrogen atmosphere and cooled to -78°C. Then, 2.38 mL of 1N cyclohexane solution of second butyl lithium (sec-BuLi) was injected into the tetrahydrofuran, and then 13.3 mL of styrene was injected dropwise over 30 minutes. The styrene was subjected to adsorption filtration separation and distillation and dehydration treatment using silica gel to remove polymerization inhibitors, and the polymerization system was confirmed to be orange. During the dropwise injection, it should be noted that the internal temperature of the reaction solution should not be above -60°C. After the dropwise injection, it was aged for 30 minutes. After that, 0.20 mL of allyl bromide was injected to stop the polymerization end. The reaction solution was heated to room temperature, the obtained reaction solution was concentrated, and replaced with methyl isobutyl ketone (MIBK). Then, 1,000 g of 2% aqueous oxalic acid solution was injected and stirred, and the bottom water layer was removed after standing. This operation was repeated three times to remove metallic Li. Then, 1,000 g of ultrapure water was injected and stirred, and the bottom water layer was removed. This operation was repeated three times to remove oxalic acid. Then, the solution was concentrated and added dropwise to 500 g of methanol to precipitate the polymer, and the solid was recovered using a Buchner funnel. The solid was dried under reduced pressure at 60°C to obtain 11.4 g of a white polymer (A-4). The obtained polymer (A-4) had an Mw of 5700, an Mn of 5200, and an Mw/Mn of 1.10.

[Synthesis Example 5] Synthesis of polymer (A-5)

After the 500 mL flask reaction container was dried under reduced pressure, 120 g of THF that had been distilled and dehydrated was injected under nitrogen atmosphere and cooled to -78°C. 2.40 mL of 1N cyclohexane solution of second butyl lithium (sec-BuLi) was injected into the THF, and then 99.9 mL of styrene and 3.24 g of 4-vinylbenzocyclobutene were dripped over 30 minutes. The styrene was previously separated by adsorption filtration and distilled and dehydrated using silica gel to remove polymerization inhibitors. The polymerization system was confirmed to be orange. After the dripping was completed, it was aged for 30 minutes. Then 1.0 g of hexamethylcyclotrisiloxane was added, aged for 30 minutes, and 1 ml of methanol was injected to terminate the polymerization terminal reaction. The reaction solution was heated to room temperature, the obtained reaction solution was concentrated, and replaced with MIBK. Then, 1,000 g of ultrapure water was injected and stirred to remove the bottom water layer. After repeating this operation five times, the solution was concentrated and added dropwise to 500 g of methanol to precipitate the polymer, and the solid was recovered using a Buchner funnel. The polymer was dried under reduced pressure at 60°C to obtain 11.2 g of a white polymer (A-5). The obtained polymer (A-5) had a Mw of 6200, a Mn of 6000, and a Mw/Mn of 1.04.

[Synthesis Example 6] Synthesis of polymer (A-6)

10 g of 1,4-dioxane and a magnetic stirrer were placed in a 300 ml three-necked flask replaced with nitrogen, and heated to 80°C. Then, 5.10 g of styrene, 3.28 g of 4-(1-propoxyethyl) vinyl benzoate, 1.35 g of N-vinyl carbazole, 0.48 g of 2,2-dimethylazobis(2-methylpropionate) (3 mol% relative to the total molar number of all monomers), and 20 g of methyl isobutyl ketone were added dropwise at a constant rate over 3 hours. After that, the mixture was aged for 3 hours. The obtained polymer solution was purified by precipitation in 500 g of methanol to precipitate a white solid, which was filtered using a Buchner funnel and dried under reduced pressure to recover 5.63 g of polymer (A-6). The obtained polymer (A-6) had an Mw of 4000, an Mn of 3000, and an Mw/Mn of 1.33.

[Synthesis Example 7] Synthesis of polymer (A-7)

In a 300 ml three-necked flask purged with nitrogen, 10 g of 1,4-dioxane and a magnetic stirrer were placed and heated to 80°C. Then, 5.10 g of styrene, 1.96 g of maleic anhydride, 2.60 g of 4-vinylbenzocyclobutene, 1.93 g of 4-dimethylmethoxysilylstyrene, 0.46 g of 2,2-dimethylazobis(2-methylpropionate) (2 mol% relative to the total molar number of all monomers), and 20 g of methyl isobutyl ketone were added dropwise at a constant rate over 3 hours. After that, the mixture was aged for 3 hours. The obtained polymer solution was purified by precipitation in 500 g of diisopropyl ether to precipitate a white solid, which was filtered using a Buchner funnel and dried under reduced pressure to recover 7.31 g of polymer (A-7). The Mw of the obtained polymer (A-7) was 4660, the Mn was 3140, and the Mw/Mn was 1.48.

[Synthesis Example 8] Synthesis of polymer (A-8)

In a 300 ml three-necked flask purged with nitrogen, 10 g of 1,4-dioxane and a magnetic stirrer were placed and heated to 80°C. Subsequently, 8.32 g of styrene, 2.22 g of isopropenyl oxazoline, 0.46 g of 2,2-dimethylazobis(2-methylpropionate) (2 mol% relative to the total molar number of all monomers), and 20 g of methyl isobutyl ketone were added dropwise at a constant rate over 3 hours. After that, the mixture was aged for 3 hours. The obtained polymer solution was purified by precipitation in 500 g of hexane to precipitate a white solid, which was filtered using a Buchner funnel and dried under reduced pressure to recover 4.31 g of polymer (A-8). The obtained polymer (A-8) had an Mw of 3140, an Mn of 2410, and an Mw/Mn of 1.30.

[Chemistry 13]

[Synthesis Example 9] Synthesis of polymer (A-9)

In a 300 ml three-necked flask purged with nitrogen, 10 g of methyl ethyl ketone and a magnetic stirrer were placed and heated to 80°C. Subsequently, 9.37 g of styrene, 1.76 g of 4-glycidyl styrene, 0.46 g of 2,2-dimethylazobis(2-methylpropionate) (2 mol% relative to the total molar number of all monomers), and 20 g of methyl isobutyl ketone were added dropwise at a constant rate over 3 hours. After that, the mixture was aged for 3 hours. The obtained polymer solution was purified by precipitation in 500 g of hexane to precipitate a white solid, which was filtered using a Buchner funnel and dried under reduced pressure to recover 4.36 g of polymer (A-9). The obtained polymer (A-9) had an Mw of 3090, an Mn of 2240, and an Mw/Mn of 1.38.

[Synthesis Example 10] Synthesis of polymer (A-10)

In a 300 ml three-necked flask purged with nitrogen, 10 g of 1,4-dioxane and a magnetic stirrer were placed and heated to 80°C. Then, 5.10 g of styrene, 4.68 g of 1-propoxyethylvinylbenzoic acid, 2.60 g of 4-vinylbenzocyclobutene, 1.93 g of 4-dimethylmethoxysilylstyrene, 0.46 g of 2,2-dimethylazobis(2-methylpropionate) (2 mol% relative to the total molar number of all monomers), and 20 g of methyl isobutyl ketone were added dropwise at a constant rate over 3 hours. Afterwards, the mixture was aged for 3 hours. The obtained polymer solution was purified by precipitation in 500 g of diisopropyl ether to precipitate a white solid, which was filtered using a Buchner funnel and dried under reduced pressure to recover 6.38 g of polymer (A-10). The Mw of the obtained polymer (A-10) was 4050, the Mn was 3260, and the Mw/Mn was 1.24.

2. Preparation of compositions for selective surface modification

[Preparation Example 1~Preparation Example 10]

98.8 g of propylene glycol monomethyl ether acetate (PGMEA) as a solvent was added to 1.20 g of polymer (A-1), and after stirring, the mixture was filtered using a high-density polyethylene filter with a pore size of 0.45 μm to prepare composition (S-1). In addition, compositions (S-2) to (S-10) were prepared in the same manner (see Table 1).

In Table 1, the abbreviations of the solvents represent the following compounds.

B-1: Propylene glycol monomethyl ether acetate

B-2: Methyl ethyl ketone

3. Evaluation

[Implementation Example 1]

<Film formation>

A 12-inch low-k substrate (manufactured by Advantec) was cut into 3 cm × 3 cm and subjected to a N ₂ /3% H ₂ ashing process in (manufactured by Ulvac, Luminous NA-1300, chamber pressure: 30 Pa, flow rate: 300 sccm, treatment time: 5 minutes). Then, the composition (S-6) was spin-coated on the ashed substrate surface using a spin coater (manufactured by Mikasa, MS-B300) at 1,500 rpm for 20 seconds and calcined at 150°C for 180 seconds under a nitrogen flow. Next, the substrate was cleaned with propylene glycol monomethyl ether acetate to remove the unadsorbed polymer.

Next, the composition (S-8) was spin-coated on the film-forming surface formed by the composition (S-6) at 1,500 rpm for 20 seconds, and calcined at 250°C for 300 seconds under a nitrogen flow. Next, the substrate was cleaned with propylene glycol monomethyl ether acetate to remove the uncrosslinked polymer.

Furthermore, instead of the 12-inch low-k substrate, a test substrate obtained by cutting a 12-inch TEOS substrate (manufactured by Advantec) into 3cm×3cm and a test substrate obtained by cutting a 12-inch thermal oxide silicon substrate (manufactured by Advantec) into 3cm×3cm were used, and the same treatment as above was performed to form a film.

<Electroless plating Cu-tight joint test>

In a 300 ml polypropylene beaker, 100 g of ultrapure water, 1.6 g of sodium hydroxide, 2.5 g of copper sulfate pentahydrate, 4 g of formalin, and 5.6 g of sodium tartrate were added to prepare an aqueous solution with a pH of 12 or higher, and the temperature was adjusted to 50°C. Next, two alkaline storage batteries of a single diameter were connected in series, and a small amount of electricity was passed through a stainless steel clip to the electroless plating aqueous solution to activate the plating solution. Then, a low-k substrate having a film cross-linked by composition (S-6) and composition (S-8) was immersed for 3 minutes to perform electroless plating. After the coating assembly, the substrate was cleaned with ultrapure water and baked in a reduced pressure oven at 150 degrees Celsius (Cdeg.) for 30 minutes. Next, a cutter was used to cut a grid-like cut on the coated Cu film, and a close-contact peeling test was performed using a cellophane tape. The case where the metal film was not peeled off to the tape side was marked as "○", and the case where it was peeled off was marked as "×". The substrates formed on TEOS substrates and thermally oxidized silicon substrates with films cross-linked using composition (S-6) and composition (S-8) were also evaluated in the same way. The evaluation results are shown in Table 2.

[Example 2~Example 4 and Comparative Example 1~Comparative Example 3]

Except for changing the selective surface modification composition used as shown in Table 2, the film formation and electroless Cu plating adhesion test were carried out in the same manner as in Example 1. The evaluation results are shown in Table 2.

[Example 25]

Except for changing the selective surface modification composition used as shown in Table 2, the film formation and electroless Cu bonding test were carried out in the same manner as in Example 1. In Table 2, "None" means that the film formation of the column was not carried out (the same applies to Tables 3 and 4). The evaluation results are shown in Table 2.

[Implementation Example 5]

<Film formation>

For a 12-inch low-k substrate, a 12-inch TEOS substrate, and a 12-inch thermally oxidized silicon substrate, composition (S-6) and composition (S-8) were used to perform the same operation as in Example 1, thereby forming a film.

<Electroless Co plating close contact test>

In a 300 ml polypropylene beaker, add 100 ml of ultrapure water, 1.55 g of cobalt sulfate, 2.12 g of sodium hypophosphite hydrate, 6.6 g of ammonium sulfate, and 10.6 g of sodium pyrophosphate to prepare an aqueous solution with a pH of 10.0 to 10.5, and adjust the temperature to 60°C. Next, immerse the low-k substrate having a film cross-linked with the composition (S-6) and the composition (S-8) for 3 minutes to perform electroless plating. After the plating assembly, the substrate is cleaned with ultrapure water and baked in a reduced pressure oven at 150C deg. for 30 minutes. Next, a cutter was used to cut a grid pattern on the coated Co film, and a close-contact peeling test was performed using a cellophane tape. The case where the metal film was not peeled off to the tape side was marked as "○", and the case where it was peeled off was marked as "×". The same evaluation was performed on the substrates formed on the TEOS substrate and the thermally oxidized silicon substrate with a film cross-linked by the composition (S-6) and the composition (S-8). The evaluation results are shown in Table 3.

[Example 6 to Example 8 and Comparative Example 4 to Comparative Example 6]

Except for changing the selective surface modification composition used as shown in Table 3, the film formation and electroless Co plating close contact test were carried out in the same manner as in Example 5. The evaluation results are shown in Table 3.

[Example 26]

Except for changing the selective surface modification composition used as shown in Table 3, the film formation and electroless Co plating close contact test were carried out in the same manner as in Example 5. The evaluation results are shown in Table 3.

According to the results of Table 2 and Table 3, it is clear that in Examples 1 to 8, which are organic films formed using a polymer (I) having a functional group F1 (first functional group) and having a functional group FM (second functional group), the metal film was not peeled off to the cellophane tape side in the close contact test, and the close contact between the organic film and the metal film was excellent. In contrast, in Comparative Examples 1 to 6, which are organic films not having a functional group FM (second functional group), the metal film was peeled off to the cellophane tape side in the close contact test, and the close contact between the metal film and the organic film was poor.

In addition, regarding Example 25 and Example 26 in which polymer (III) was used to form an organic film, the metal film did not peel off to the cellophane tape side in the adhesion test, and the adhesion between the organic film and the metal film was excellent.

[Implementation Example 9]

<Study on embedding trench through-hole patterns with Cu on the bottom surface>

A 12-inch substrate (manufactured by Advanced Material Technologies) with a sidewall comprising thermally oxidized silicon, a bottom surface comprising a copper film, and a trench through-hole pattern comprising a width of 50nm/depth of 100nm was cut into 3cm×3cm and immersed in a 2.38% trimethylammonium hydroxide aqueous solution for 10 minutes. Then, it was immersed in ultrapure water and the alkali was removed to complete the surface modification. The composition (S-1) was applied to the substrate and spin-coated (manufactured by Mikasa, MS-B300) at 1,500rpm for 20 seconds, and calcined at 150°C for 180 seconds under a nitrogen flow. Next, the substrate was cleaned with propylene glycol monomethyl ether acetate to remove the unadsorbed polymer.

Next, the composition (S-6) was spun at 1,500 rpm for 20 seconds and calcined at 150°C for 180 seconds under a nitrogen flow. Next, the substrate was cleaned with propylene glycol monomethyl ether acetate to remove the polymer that was not adsorbed on the oxide. Furthermore, the composition (S-8) was spun at 1,500 rpm for 20 seconds and calcined at 250°C for 300 seconds under a nitrogen flow. Next, the substrate was cleaned with propylene glycol monomethyl ether acetate to remove the uncrosslinked polymer.

Finally, the substrate was immersed in acetic acid solution for 10 minutes and cleaned with ultrapure water to remove only the film containing composition (S-1) adsorbed on the copper thin film on the bottom surface. Through the above operation, a trench substrate was obtained in which composition (S-6) and composition (S-8) were applied to the inner wall surface of the through hole and the Cu layer was exposed on the bottom surface inside the through hole.

The substrate was immersed in the electroless Cu plating solution to grow Cu in the grooves. After plating and assembly, the substrate was cleaned with ultrapure water and baked in a 150C depressurized oven for 30 minutes. The obtained substrate was observed by scanning electron microscopy (SEM) to confirm that Cu was embedded in the grooves without gaps. From the wide-angle view, the situation where all 10 grooves were embedded was set as "○", and the situation where there was poor embedding was set as "×". The evaluation results are shown in Table 4.

<Study on embedding trench through-hole pattern with Co on the bottom surface>

A 12-inch substrate (manufactured by Advanced Material Technologies) with a through-hole pattern of 50nm wide/100nm deep and thermally oxidized silicon on the sidewalls and copper film on the bottom surface was cut into 3cm×3cm, immersed in a 2.38% trimethylammonium hydroxide aqueous solution for 10 minutes, and then immersed in ultrapure water to remove alkali to complete surface modification. The composition (S-1) was applied to the substrate and spin-coated at 1,500rpm for 20 seconds (manufactured by Mikasa, MS-B300), and calcined at 150°C for 180 seconds under a nitrogen flow. Next, the substrate was cleaned with propylene glycol monomethyl ether acetate to remove unabsorbed polymer.

Next, the composition (S-6) was spun at 1,500 rpm for 20 seconds and calcined at 150°C for 180 seconds. Next, the substrate was cleaned with propylene glycol monomethyl ether acetate to remove the polymer that was not adsorbed on the oxide. Furthermore, the composition (S-8) was spun at 1,500 rpm for 20 seconds and calcined at 250°C under a nitrogen flow for 300 seconds. Next, the substrate was cleaned with propylene glycol monomethyl ether acetate to remove the uncrosslinked polymer.

Finally, the substrate was immersed in acetic acid stock solution for 10 minutes and cleaned with ultrapure water to remove only the film containing composition (S-1) adsorbed on the bottom surface copper film. Through the above operation, a trench substrate was obtained in which a film insoluble by composition (S-6) and composition (S-8) was given on the inner wall surface of the through hole, and the Co layer was exposed on the bottom surface inside the through hole.

The substrate was immersed in the electroless Co plating solution to grow Co in the grooves. After plating and assembly, the substrate was cleaned with ultrapure water and baked in a 150C depressurized oven for 30 minutes. The obtained substrate was observed by cross-section SEM (manufactured by Hitachi High-technologies, CG5000), and it was confirmed that Co was embedded in the grooves without gaps. From the wide-angle view, the situation where all 10 grooves were embedded was set as "○", and the situation where there was poor embedding was set as "×". The evaluation results are shown in Table 4.

[Example 10 to Example 24 and Comparative Example 7 to Comparative Example 9]

Except for changing the selective surface modification composition used as shown in Table 4, the bottom surface groove via pattern embedding research with Cu and the bottom surface groove via pattern embedding research with Co were carried out in the same manner as in Example 9. The evaluation results are summarized in Table 4.

[Example 27~Example 32]

Except for changing the selective surface modification composition used as shown in Table 4, the bottom surface groove via pattern embedding research with Cu and the bottom surface groove via pattern embedding research with Co were carried out in the same manner as in Example 9. The evaluation results are summarized in Table 4.

According to the results in Table 4, regarding Examples 9 to 24 and 27 to 32 in which metal is embedded in the through hole by the present manufacturing method, there is no void in the groove and the metal embedding property is good. In contrast, regarding Comparative Example 7 in which an organic film is formed on the inner wall surface of the through hole using the composition (S-5), and Comparative Example 8 and Comparative Example 9 in which an organic film is formed on the inner surface of the through hole using only the composition (S-8) or the composition (S-9), voids are generated in the groove and the metal embedding property is poor.

10:Wiring board

11:Through hole

12: Inner wall surface

13:Wiring

14: Insulating layer

15: Bottom

16: The first organic film

17: Second organic film

17a: First floor

17b: Second level

18: Plating layer

Claims (18)

A method for manufacturing a multi-layer wiring substrate, comprising: a first forming step of forming a first organic film on the wiring inside a through hole, wherein the through hole is formed in an insulating layer provided on the wiring so as to penetrate the insulating layer in a thickness direction; a second forming step of forming a second organic film on the inner wall surface of the through hole after forming the first organic film ; a removal step of removing the first organic film after forming the second organic film; and a plating step of forming a metal layer by plating treatment inside the through hole after removing the first organic film, wherein the second organic film is formed using a polymer (I) having a first functional group that can interact with a group on the surface of the insulating layer and having a second functional group that can form a bond with the metal contained in the metal layer. A method for manufacturing a multilayer wiring board as described in claim 1, wherein the polymer (I) has the first functional group and a cross-linking group, the second organic film is a laminated film of a first layer and a second layer, the first layer is formed on the inner wall surface using the polymer (I), and the second layer is formed on the first layer using a polymer (II) having a third functional group that can form a bond with the cross-linking group. A method for manufacturing a multilayer wiring board as described in claim 2, wherein the crosslinking group is at least one selected from the group consisting of anhydride groups and protected carboxyl groups. A method for manufacturing a multi-layer wiring board as described in claim 2 or claim 3, wherein the third functional group is at least one of an oxazoline group and an epoxy group. A method for manufacturing a multilayer wiring board as described in claim 2 or claim 3, wherein the polymer (II) has a structural unit derived from a monomer having an aromatic ring. A method for manufacturing a multi-layer wiring substrate as described in claim 1, wherein the second organic film is a single-layer film. A method for manufacturing a multilayer wiring board as described in any one of claims 1 to 3, wherein the insulating layer has a group on the surface bonded to a silicon atom and selected from the group consisting of a hydrogen atom, a hydroxyl group, a pendoxy group and -N(R ¹ ) ₂ , wherein R ¹ is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and the first functional group is at least one selected from the group consisting of a silanol group, an alkoxysilyl group, -N(Si(R ⁵ ) ₃ ) ₂ , an amino group, a hydroxyl group, and a conjugated nitrogen-containing heterocyclic group, wherein R ⁵ is independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms. A method for producing a multilayer wiring board as described in any one of claims 1 to 3, wherein the polymer (I) has a structural unit derived from a monomer having an aromatic ring. A method for manufacturing a multilayer wiring substrate as described in any one of claims 1 to 3, wherein the first organic film is formed using a compound having at least one selected from the group consisting of a cyano group, a boric acid group, a phosphoric acid group, a phosphonic acid group, a phosphate group, a phosphonic acid group, a thiol group, a disulfide group, and a group containing a carbon-carbon unsaturated bond. A method for manufacturing a multilayer wiring substrate as described in any one of claim 1 to claim 3, wherein the wiring contains Cu or Co. A method for manufacturing a multi-layer wiring board as described in any one of claim 1 to claim 3, wherein the plating step is a step of performing electroless plating inside the through hole. A method for manufacturing a multilayer wiring substrate as described in any one of claim 1 to claim 3, wherein the metal layer contains Cu or Co. The method for manufacturing a multi-layer wiring substrate as described in any one of claims 1 to 3 further comprises the following step: performing an ashing treatment using N ₂ /H ₂ gas or O ₂ gas on the surface of the substrate before the first organic film is formed in the first forming step. The method for manufacturing a multilayer wiring substrate as described in any one of claims 1 to 3 further includes the following step: bringing a treatment solution containing tetramethylammonium hydroxide (TMAH), hydrogen fluoride (HF), ammonia (NH ₃ ), tetramethylammonium fluoride (TMAF), or citric acid into contact with the surface of the substrate before the first organic film is formed by the first forming step. A method for manufacturing a multi-layer wiring board as described in any one of claim 1 to claim 3, wherein the removal step is a step of removing the first organic film by contacting the first organic film with an organic acid, and further includes a step of contacting the substrate surface after the removal step with an alkali. A kit for forming a laminated film is used for pre-treatment of forming a metal layer inside a through hole of a multi-layer wiring substrate by plating treatment, and the kit comprises: a polymer (I) having a functional group and a cross-linking group, wherein the functional group can interact with at least one group selected from the group consisting of a hydrogen atom, a hydroxyl group, a pendoxy group and -N( ^R1 ) ₂ that is bonded to a silicon atom, wherein ^R1 is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; and a polymer (II) having a functional group that can form a bond with the cross-linking group. A composition for pre-treatment for forming a metal layer inside a through hole of a multi-layer wiring substrate by plating treatment, the composition comprising: a polymer having a functional group and a cross-linking group which is at least one selected from the group consisting of anhydride groups and protected carboxyl groups, the functional group being capable of interacting with a group which is bonded to a silicon atom and is at least one selected from the group consisting of a hydrogen atom, a hydroxyl group, a pendoxy group and -N( ^R1 ) ₂ , wherein ^R1 is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; and a solvent. The composition according to claim 17, wherein the polymer has a structural unit represented by the following formula (1) as a structural unit having the functional group,

In formula (1), R is a hydrogen atom, a monovalent alkyl group having 1 to 5 carbon atoms, a halogen atom, or a halogenated alkyl group having 1 to 5 carbon atoms; ^R2 is a monovalent alkyl group having 1 to 5 carbon atoms; ^R3 is an alkoxy group having 1 to 5 carbon atoms; ^R10 is a monovalent alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a halogenated atom; a is an integer of 0 to 2, and b is an integer of 1 to 3; wherein a+b=3; c is an integer of 0 to 4; when a is 2, multiple ^R2s are the same or different; when b is 2 or 3, multiple ^R3s are the same or different; when c is 2 or more, multiple ^R10s are the same or different.