TWI651017B - Method for roughening surface - Google Patents

Abstract

The present invention provides a method of roughening the surface of a substrate.

The surface roughening method of the present invention comprises the following steps: a first step of coating a composition containing the inorganic particles (a1) and the organic resin (a2) on a substrate or a layer above the substrate (a3) And drying and hardening to form the organic resin layer (A); and the second step of etching from the upper side of the substrate to roughen the surface of the same substrate. The etching is performed at least once, and at least one of the etching is performed by gas etching with an oxygen-based gas or wet etching with an acidic aqueous solution. The inorganic particles (a1) are metal oxide particles having an average particle diameter of 5 to 1000 nm. The composition (a3) contains a solution of a cerium oxide sol in which an inorganic particle (a1) is dispersed in an organic solvent and an organic resin (a2). The organic resin layer (A) contains the inorganic particles (a1) in a ratio of 5 to 50 parts by mass based on 100 parts by mass of the organic resin (a2). The above composition (a3) further contains a crosslinking agent and a crosslinking catalyst. The surface roughening layer formed is a light extraction layer of the LED.

Description

Surface roughening method

The present invention relates to a surface roughening method on a substrate, which is particularly applicable to a light extraction layer of an LED or the like.

In recent years, LED technology has been utilized. Then, studies have been conducted on the light extraction layer in order to improve the luminous efficiency of the technology.

A light extraction layer such as an LED has been proposed as a method in which a light-scattering layer is provided between a light-emitting layer inside a organic EL element and a substrate (refer to Japanese Patent Laid-Open Publication No. Hei. As the light-scattering layer, those in which fine particles different in refractive index from the resin are dispersed in a transparent resin can be used. The light that is emitted in the light-emitting portion is scattered by the light-scattering layer, and changes the traveling direction in various directions. As a result of multiple scattering, at the interface with the air, light incident on an angular region within the total reflection angle can be taken out. In the light-scattering layer, since the traveling direction of the light is arbitrarily changed, the size distribution of the fine particles is wide, the arrangement of the fine particles is arbitrary, and the volume fraction of the fine particles is preferably large. Here, if the size distribution of the fine particles is narrow, or the volume fraction of the fine particles is small, the scattering energy of the light scattering layer becomes low. However, if the size of the microparticles is widely distributed, it is difficult to make the microparticles ideally arranged in the resin, and When the particle size distribution is wide, if the volume fraction is to be increased, the flatness of the light-scattering layer is remarkably lowered. Therefore, the flatness of the light-emitting portion of the film structure is impaired, and the reliability of the light-emitting element is largely lowered.

Further, a light extraction layer comprising: a reflective layer; and a three-dimensional diffraction layer formed on the reflective layer and containing fine particles having a variation coefficient of 10% or less and a matrix having a refractive index different from the fine particles The volume fraction of the volume of the microparticles to the three-dimensional diffraction layer is 50% or more, forming the first region in which the microparticles are arranged to have a short-distance periodicity, and further, the first region is formed to be adjacent to each other and aggregated in any direction. Second area. (refer to Japanese Patent Document 2).

[Prior patent documents] [Patent Literature]

[Patent Document 1] Japanese Special Opening 2006-107744

[Patent Document 2] Japanese Special Open 2009-216862

[Summary of the Invention]

It is an object of the present invention to provide a method of roughening a surface of a substrate. In particular, the present invention provides a method of using a layer in which an inorganic substance and an organic substance are mixed on a substrate, and forming an oxygen-etched portion and an unetched surface on the surface of the substrate by using an etching rate difference between oxygen of the inorganic substance and the organic substance. Surface roughening layer; then, further, with a rough surface The layer is etched by oxygen or a fluorine-based gas as a mask to roughen the surface of the substrate, for example, fine irregularities are formed on the substrate, and the etching is changed to a gas etching by wet etching using an acidic aqueous solution. A method of roughening the surface.

A first aspect of the present invention provides a surface roughening method comprising the steps of: coating a first step on a substrate or coating a layer containing an inorganic particle (a1) and an organic resin (a2) on a layer above the substrate. The composition (a3) is dried and hardened to form an organic resin layer (A), and the second step is performed by etching from above the substrate to roughen the surface of the same substrate.

The second aspect is the surface roughening method according to the first aspect, wherein the etching is performed at least once, and at least one of the etching is performed by an oxygen-based gas.

The third aspect is the surface roughening method according to the first aspect, wherein the etching is performed by wet etching with an acidic aqueous solution.

The surface roughening method according to any one of the first to third aspects, wherein the inorganic particles (a1) are metal oxide particles having an average particle diameter of 5 to 1000 nm.

The fifth aspect is a surface roughening method according to the first aspect, wherein the composition (a3) contains a cerium oxide sol as an inorganic particle (a1) in which an cerium oxide is dispersed in an organic solvent, and an organic resin ( A2) solution.

The sixth aspect is a surface roughening method according to any one of the first to fifth aspects, The organic resin layer (A) contains the inorganic particles (a1) in a ratio of 5 to 50 parts by mass based on 100 parts by mass of the organic resin (a2).

The surface roughening method according to any one of the first to sixth aspect, wherein the organic resin (a2) has a functional group comprising a hydroxyl group, a carboxyl group, an amine group, or the like. The base repeat unit is constructed.

The eighth aspect is the surface roughening method according to any one of the first to seventh aspects, which is formed by etching to a length-width ratio of a hole formed by (height) / (diameter) formed on the substrate. In the range of 0.1 to 20.

The surface roughening method according to any one of the first to eighth aspects, wherein the organic resin layer (A) has a film thickness of 0.001 to 10 μm.

The tenth aspect is the surface roughening method according to any one of the second to ninth aspects, wherein the first step is the first step, which is coated on the substrate or coated with the organic resin on the layer above the substrate. The composition (b3) of (b2) is dried and hardened to form an organic resin layer (B); and further, the composition containing the inorganic particles (a1) and the organic resin (a2) is coated on the organic resin layer (B). The object (a3) is dried and hardened to form an organic resin layer (A).

The eleventh aspect is the surface roughening method according to the tenth aspect, wherein the organic resin (b2) is a resin selected from the group consisting of organic resins (a2).

The surface roughening method according to the tenth or eleventh aspect, wherein the organic resin layer (B) is a layer having a film thickness of 0.001 to 10 μm.

The thirteenth aspect is a surface roughening method according to any one of the first to the twelfth aspects. The method wherein the composition (a3) and/or the composition (b3) further comprises a crosslinking agent and a crosslinking catalyst.

The surface roughening method according to any one of the first to thirteenth aspects, wherein the surface roughening layer formed is a light extraction layer of the LED.

By the present invention, a novel method of roughening the surface of a substrate can be provided. In particular, the method of the present invention can utilize a layer in which an inorganic substance and an organic substance are mixed on a substrate, and an etching rate of oxygen of the inorganic substance and the organic substance is used, so that an oxygen-etched portion and an unetched surface can be formed on the surface of the substrate. a surface roughening layer; further, etching with an oxygen or fluorine-based gas by using the surface roughening layer as a mask to roughen the surface of the substrate, for example, forming fine irregularities on the substrate, and further, according to the present invention Alternatively, the surface can be roughened by changing the gas etching to wet etching using an acidic aqueous solution.

Fig. 1 is a cross-sectional view (100,000 times magnification) of the organic resin layer (B) and the organic resin layer (A) on the SiO ₂ film-coated wafer obtained in Example 1.

2 is a cross-sectional view of the organic resin layer (B) and the organic resin layer (A) on the SiO ₂ film-coated wafer obtained in Example 1, (the magnification is 100,000 times, and the inclination angle is 20 degrees).

Fig. 3 is a cross-sectional view (100,000 times magnification) of the organic resin layer (B) and the organic resin layer (A) on the SiO ₂ film-coated wafer obtained in Example 2.

4 is a cross-sectional view (100,000 times magnification) of the organic resin layer (B) and the organic resin layer (A) on the SiO ₂ film-coated wafer obtained in Example 4.

Fig. 5 is a cross-sectional view (magnification: 100,000 times) of the organic resin layer (A) on the SiO ₂ film-coated wafer obtained in Example 8.

Fig. 6 is a cross-sectional view (magnification: 100,000 times) of the organic resin layer (B) on the SiO ₂ film-coated wafer obtained in Comparative Example 1.

7 sectional view of the system SiO ₂ film is coated on the wafer obtained in Example 1 of SiO ₂ film embodiment (100,000 times magnification).

FIG processing system 8 SiO ₂ film on the wafer coated SiO embodiment of Example ₁₂ to give the film a cross-sectional view (magnification of 100,000 times, inclination angle 20 degrees).

In the organic EL display, an ITO electrode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and an electrode are formed on a substrate such as glass or transparent plastic.

Further, an N-type semiconductor, a light-emitting region, a P-type semiconductor, an ITO electrode, and an SiO ₂ layer were formed on the sapphire.

In the present invention, the surface of the glass or the transparent plastic or the SiO ₂ layer or the like used as the light extraction layer can be roughened, for example, fine concavities and convexities are formed to reduce the reflection of light, whereby the luminous efficiency can be improved.

Conventional methods include a method of attaching inorganic particles or the like to a substrate used for a light extraction layer, but there is a problem in adhesion. The present invention is different from the above methods in that the surface of the substrate is roughened by physical etching, for example, irregularities are formed.

The present invention includes the following steps: a first step of coating a composition (a3) containing inorganic particles (a1) and an organic resin (a2) on a layer to be roughened or on a layer above the substrate, and The organic resin layer (A) is formed by drying and hardening, and the second step is followed by etching with a gas from above the substrate to roughen the surface of the same substrate. The difference in etching rate of oxygen of the inorganic particles (a1) and the organic resin (a2) contained in the organic resin (A) is used to form irregularities in the organic resin layer (A). After the unevenness of the organic resin layer (A), the portion to be etched and the portion not to be etched are formed on the surface of the substrate by etching of oxygen or another gas (fluorine-based gas or chlorine-based gas) to form irregularities. .

The irregularities formed as the case may be etched to form an etch layer below the substrate.

The drying and hardening can be carried out simultaneously or after drying.

The organic resin layer (A) functions as a mask after performing oxygen etching. An organic resin layer (B) containing no inorganic particles is formed on the substrate, an organic resin layer (A) containing inorganic particles is formed thereon, and etching is performed with oxygen, and the layers (A) and (B) are used as a mask. The thickness of the film is thick, and the etching is caused by oxygen gas or other gas etching (for example, a fluorine-based gas), so that it has a high aspect ratio. The roughening of the substrate is made possible.

Further, even if wet etching using an acidic aqueous solution is changed to gas etching, the roughening can be performed in the same manner as described above.

The roughening is a chemical or physical change on the surface of the substrate by roughening the surface of the substrate by etching. An example of this is that irregularities are formed on the surface of the substrate.

The roughening of the substrate varies depending on the average particle diameter of the inorganic particles or the concentration (ratio) of the inorganic particles contained in the organic resin layer (A), and may be depending on the roughened shape (concavo-convex shape) on the substrate as needed. Decide.

In the present invention, the etching is performed at least once, and at least one of the etching is performed by oxygen etching using an oxygen-based gas. The oxygen-based gas system contains oxygen as an etching gas of a gas component, and etches the organic resin layer (A) or the organic resin (a2) or the organic resin (b2) present in the lower organic resin layer (B) in the vertical direction by oxygen. Further, the inorganic particles (a1) in the organic resin layer (A) exhibit an etching resistance against oxygen. Then, the etching of the organic resin layer (A) or the organic resin layer (B) is at the stage of reaching the substrate surface, and then, when etching with an oxygen-based gas, or by other gases (for example, a gas containing a fluorine component) Etching the substrate.

Further, in the present invention, the etching is performed by wet etching using an acidic aqueous solution. The organic resin layer (A) or the organic resin (a2) or the organic resin (b2) present in the lower organic resin layer (B) is etched in the vertical direction by an acidic aqueous solution, and the organic resin layer (A) The inorganic particles (a1) exhibit an etching resistance to an acidic aqueous solution. Then organic The etching of the resin layer (A) or the organic resin layer (B) is at the stage of reaching the substrate surface, and then the substrate can be etched with an acidic aqueous solution.

The acidic aqueous solution used in the wet etching may contain an acid and water, and if necessary, contains hydrogen peroxide or a water-soluble organic solvent. As the acid, sulfuric acid, nitric acid, or hydrochloric acid can be used. The water-soluble organic solvent is an alcoholic or etheric or ketone-based or ester-based system. For example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monobutyl ether, propylene glycol monobutyl ether acetate , diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate , propylene glycol monopropyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethoxy acetic acid Ethyl ester, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate , 3-ethoxypropionate ethyl ester, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate and the like. These organic solvents may be used singly or in combination of two or more.

The concentration of the acid in the total solvent of the water and the organic solvent is 0.01 to 97% by mass, and the concentration of the hydrogen peroxide in the total solvent is 0.01 to 40% by mass.

In the present invention, both gas etching and wet etching can be performed in combination.

A metal oxide is used for the inorganic particles (a1) used in the present invention. For example, cerium oxide (cerium oxide), titanium oxide, zirconium oxide, aluminum oxide, or the like can be mentioned. It is especially suitable for cerium oxide (cerium oxide). Average particle size It is used in the range of 5 to 1000 nm, or 5 to 200 nm, or 10 to 50 nm. It is preferable that the inorganic particles are added to the organic resin (a2) in a colloidal state, and a solution of the sol dispersed in the organic solvent of the inorganic particles (a1) is added to the organic resin (a2) or the organic resin (a2). In order to obtain the composition (a3), the composition (a3) is coated on the substrate or coated on the substrate on which the organic resin layer (B) is formed in advance.

Typically, a composition (a3) is obtained by mixing a solution of a cerium oxide sol in which an inorganic particle (a1) of cerium oxide is dispersed in an organic solvent and an organic resin (a2).

In the organic resin layer (A) obtained by coating the composition (a3) in the composition (a3), the inorganic particles are contained in a ratio of 1 to 100 parts by mass based on 100 parts by mass of the organic resin (a2) ( Formed by a1).

The organic resin (a2) is preferably a functional group in which a repeating unit has a polar group having a hydroxyl group, a carboxyl group, an amine group, or the like, as a functional group. It is preferred that these functional groups have compatibility with inorganic particles or coating properties on a substrate.

The resin containing the above functional group may, for example, be an acrylic resin or a novolac resin.

The acrylic resin may, for example, be a homopolymer of a monomer having a hydroxyl group, a carboxyl group or an amine group, or a copolymer thereof with another resin. The monomer may, for example, be (meth)acrylic acid, or (meth)acrylate, or a vinyl compound.

A monomer having a hydroxyl group, a carboxyl group or an amine group may, for example, Acrylic acid, (meth) acrylamide, hydroxyalkyl (meth) acrylate, carboxyalkyl (meth) acrylate, amino alkyl (meth) acrylate, hydroxy styrene, hydroxy vinyl A homopolymer of a monomer such as naphthalene or vinyl benzoate or a copolymer with other resins. The other resin may, for example, be a monomer which does not contain the above functional group, and examples thereof include an alkyl (meth) acrylate such as methyl (meth) acrylate or ethyl (meth) acrylate, and a phenyl group (A). Acrylate, benzyl (meth) acrylate, styrene, t-butyl styrene, vinyl naphthalene, and the like.

These acrylic single systems are obtained by radical polymerization or cationic polymerization to obtain the above acrylic resin.

The novolak resin may, for example, be a novolak resin obtained by reacting a compound containing a phenolic hydroxyl group or an aromatic compound containing an amine group with an aldehyde compound, or a compound containing a phenolic hydroxyl group or an aromatic compound containing an amine group. A novolak resin obtained by a reaction with an aldehyde compound having a hydroxyl group, a carboxyl group or an amine group. Examples of the compound having a phenolic hydroxyl group include monovalent phenol such as phenol, cresol, salicylic acid, and naphthol, divalent phenol such as catechol or m-xylenol, pyrogallol, and phloroglucinol. A polynuclear phenol such as a trivalent phenol, a biphenol, a bisphenol A or a bisphenol S.

Examples of the aromatic group-containing aromatic compound include pyrrole, phenylnaphthylamine, phenylhydrazine, carbazole and the like.

Examples of the aldehydes include formaldehyde, polyoxymethylene, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, valeraldehyde, capronaldehyde, 2-methylbutanal, Hexylaldehyde, and undecylaldehyde. , 7-methoxy-3,7-dimethyloctanal, cyclohexanal, 3-methyl-2-butanal, glyoxal, propane a saturated aliphatic aldehyde such as aldehyde, succinaldehyde, glutaraldehyde or adipaldehyde; an unsaturated aliphatic aldehyde such as acrolein or methacrolein; a heterocyclic aldehyde such as furaldehyde or pyridaldehyde; Benzaldehyde, naphthaldehyde, onion aldehyde, phenanthrene, salicylaldehyde, phenylacetaldehyde, 3-phenylpropanal, benzyl aldehyde, (N,N-dimethylamino)benzaldehyde, acetamidine An aromatic aldehyde such as benzaldehyde or the like. Among them, an aldehyde compound having a hydroxyl group or a carboxyl group is preferred, and examples thereof include hydroxybenzaldehyde, carboxybenzaldehyde, hydroxynaphthaldehyde, carboxynaphthaldehyde, hydroxyfurfural, and carboxyfurfural.

The phenolic hydroxyl group-containing compound or the amine group-containing aromatic compound and the aldehyde compound may be used in an amount of 0.1 to 10 equivalents per 1 equivalent of the phenyl group. The acid catalyst used in the above condensation reaction may be, for example, an inorganic acid such as sulfuric acid, phosphoric acid or perchloric acid, an organic sulfonic acid such as p-toluenesulfonic acid or p-toluenesulfonic acid monohydrate, or a carboxylic acid such as formic acid or oxalic acid. . The amount of the acid catalyst used is various depending on the type of the acid to be used. In general, it is 0.001 to 10,000 parts by mass, preferably 0.01 to 1000 parts by mass, more preferably 0.1 to 100, per 100 parts by mass of the total of the phenolic hydroxyl group-containing compound or the amine group-containing aromatic compound and the aldehyde compound. Parts by mass.

The above condensation reaction can be carried out in the absence of a solvent, but is generally carried out using a solvent. The solvent may be used as long as it does not inhibit the reaction. For example, a cyclic ether such as tetrahydrofuran or dioxane may be mentioned. Further, the acid catalyst to be used may be, for example, a liquid of formic acid, and may function as a solvent.

The reaction temperature during condensation is generally from 40 ° C to 200 ° C. reaction The time can be variously selected depending on the reaction temperature, but it is usually from about 30 minutes to about 50 hours.

In the organic resin (a2) used in the present invention, the organic resin (b2) described below can be exemplified below.

The composition (a3) used in the present invention contains the above organic resin (a2) and inorganic particles (a1) and a solvent. An additive such as a surfactant may be contained as needed.

The solid content of the composition is 0.1 to 70% by mass, or 0.1 to 60% by mass. The solid fraction removes the content ratio of the entire component of the solvent from the composition (a3). The organic resin (a2) may be contained in a ratio of from 1 to 99.9% by mass or from 20 to 99.9% by mass in the solid content.

The organic resin (a2) used in the present invention has a weight average molecular weight of 600 to 1,000,000, or 600 to 200,000.

Moreover, the surface roughening method of the present invention includes a first step of applying a composition (b3) containing an organic resin (b2) onto a substrate, and drying and hardening to form an organic resin layer (B). Further, a composition (a3) containing the inorganic particles (a1) and the organic resin (a2) is applied onto the organic resin layer (B), and dried and hardened to form an organic resin layer (A) (this step is specifically called In the first step, the second step is performed by etching (gas etching or wet etching) from above the substrate to roughen the surface of the same substrate.

The organic resin (b2) of the organic resin layer (B) can be selected from resins in the same range as the organic resin (a2) of the above organic resin layer (A). Further, the same resin may be used for the organic resin (b2) and the organic resin (a2).

The composition (b3) used in the present invention contains the above organic resin (b2) and a solvent. An additive such as a surfactant may be contained as needed. The solid shape of the composition is 0.1 to 70% by mass, or 0.1 to 60. quality%. The solid fraction removes the content ratio of the entire component of the solvent from the composition (b3). The organic resin (b2) may be contained in a ratio of from 1 to 100% by mass, or from 1 to 99.9% by mass, or from 50 to 99.9% by mass in the solid content.

The organic resin (b2) used in the present invention has a weight average molecular weight of 600 to 1,000,000, or 600 to 200,000.

The organic resin layer (B) is obtained by coating the composition (b3) on a substrate and drying and hardening, but applying an organic resin layer (A) to the upper layer of the organic resin layer (B) to prevent mutual Since it is mixed (layered), the composition (b3) may further contain a crosslinking agent and a crosslinking catalyst.

Further, the organic resin layer (A) may contain a crosslinking agent and a crosslinking catalyst in the composition (a3) as needed.

The crosslinking agent to be used for the composition (a3) or the composition (b3) may, for example, be a melamine-based or substituted urea-based polymer or the like. It is preferred to have at least two crosslinkers which form crosslinkable substituents, methoxymethylated glycol urea, butoxymethylated glycol urea, methoxymethylated melamine, butoxylate Alkyl melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine, methoxymethylated urea, butoxymethylated urea, or methoxymethylated sulfur a compound such as urea. Further, a condensate of these compounds can also be used. The amount of the crosslinking agent to be added varies depending on the coating solvent to be used, the base substrate to be used, the desired solution viscosity, the desired film shape, and the like, but is preferably 0.001 to 80% by mass based on the total solid content, preferably 0.01 to 50% by mass, more preferably 0.05 to 40% by mass.

In the present invention, the catalyst for promoting the above crosslinking reaction can be paired with toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium p-toluenesulfonic acid, salicylic acid, sulfosalicylic acid, citric acid, benzoic acid, An acidic compound such as hydroxybenzoic acid or naphthalenecarboxylic acid or/and 2,4,4,6-tetrabromocyclohexanedione, benzoin toluenesulfonic acid, 2-nitrobenzyltoluenesulfonic acid, or other organic sulfonate A thermal acid generator such as an acid alkyl ester. The blending amount is 0.0001 to 20% by mass, preferably 0.0005 to 10% by mass, more preferably 0.01 to 3% by mass, based on the total solid content.

In the present invention, the surfactant used in the composition (a3) or the composition (b3) may, for example, be polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxygen. Polyoxyethylene alkyl allyl ethers such as polyoxyethylene alkyl ethers such as ethylene oleyl ether, polyoxyethylene octyl phenol ether, polyoxyethylene nonyl phenol ether, and polyoxyethylene/polyoxypropylene Segment copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan III Sorbitol fatty acid esters such as stearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as sorbitan trioleate and polyoxyethylene sorbitan tristearate, EFTOP EF301, EF303, EF352 (() Products, product name), Megafac F171, F173, R40 (Greater Japan Ink (share) system, trade name), Fluorad FC430, FC 431 (Sumitomo 3M (share) system, trade name), Asahiguard AG 710, Sarflon S382, SC101, A fluorine-based surfactant such as SC102, SC103, SC104, SC105, or SC106 (product of Asahi Glass Co., Ltd., trade name), or an organic siloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.). The amount of the surfactant to be added is generally 2.0% by mass or less, and preferably 1.0% by mass or less based on the total solid content of the underlayer film material for lithography etching of the present invention. These surfactants may be added singly or in combination of two or more.

In the present invention, a solvent used for the composition (a3) or the composition (b3) may be ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl ester. Fibril acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monoethyl Ethyl acetate, propylene glycol monopropyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate Ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3-ethoxy Methyl propyl propionate, ethyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate and the like. These organic solvents may be used singly or in combination of two or more.

Further, it can be used by mixing a high boiling point solvent such as propylene glycol monobutyl ether or propylene glycol monobutyl ether acetate. Among these solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl lactate, and cyclohexanone are preferable for the improvement of leveling property.

Next, if the surface roughening method of the present invention is explained, The composition (b3) or the composition (a3) is applied onto the surface of the substrate or the substrate by a suitable coating method such as a spin coater or a coater, and then baked and hardened to prepare an organic resin layer ( A) or organic resin layer (B).

In the present invention, the organic resin layer (A) has a film thickness of 0.001 to 10 μm or 0.005 to 3.0 μm, and the organic resin layer (B) has a film thickness of 0.001 to 10 μm or 0.005 to 3.0 μm.

Further, the conditions for baking after coating are from 0.5 to 120 minutes at 80 to 400 °C.

The organic resin layer (B) is formed on the substrate, the organic resin layer (A) is formed thereon, or the organic resin layer (A) is formed without forming the organic resin layer (B), and after hardening under the above conditions, the substrate is cured. The upper surface is etched with a gas to roughen the surface of the same substrate. This etching gas is first etched with an oxygen-based gas, whereby the portion where the inorganic particles (a1) do not exist is cut in the vertical direction. The etching may be performed at the stage of reaching the substrate surface, and then etching may be performed by an oxygen-based gas. However, it may be etched by another gas (for example, a fluorine-based gas), whereby irregularities may be formed on the substrate to be roughened.

The substrate is also included in the substrate itself or a coated substrate such as SiO ₂ is coated on the substrate, and the surface of the substrate or the coated substrate can be roughened.

Examples of the oxygen-based gas include oxygen, a mixed gas of oxygen and nitrogen, and a mixed gas of oxygen and argon.

Other gases include, for example, a fluorine-based gas or a chlorine-based gas. For example, a fluorine-containing gas such as CF ₄ , C ₄ F ₈ , C ₄ F ₆ , CHF ₃ or CH ₂ F _{2 may} be mentioned. Further, a chlorine-based gas such as Cl ₂ may also be used.

Further, in the present invention, the organic resin layer (B) is formed on the substrate, the organic resin layer (A) is formed thereon, or the organic resin layer (B) is formed without forming the organic resin layer (B). After curing under the above conditions, the surface of the same substrate is roughened by etching with the acidic aqueous solution from above the substrate. By this wet etching gas, the portion where the inorganic particles (a1) are not present is cut in the vertical direction. The etching reaches the stage of the substrate surface, and then etching can be performed by an acidic aqueous solution, whereby irregularities can be formed on the substrate to be roughened.

The substrate is also included in the substrate itself or a coated substrate such as SiO ₂ is coated on the substrate, and the surface of the substrate or the coated substrate can be roughened.

The aspect ratio of the hole represented by (height) / (diameter) formed on the substrate by etching with a gas or an acidic aqueous solution is formed in the range of 0.1 to 20 or 0.1 to 10, but generally, the etching time is 1 second. ~1 hour.

Further, the roughened surface obtained in this manner can be used as a mask to process the substrate present in the lower layer. The processing of the underlying substrate may be dry etching or wet etching using a gas.

The gas system for etching may, for example, be a fluorine-based gas or a chlorine-based gas. For example, a fluorine-containing gas such as CF ₄ , C ₄ F ₈ , C ₄ F ₆ , CHF ₃ or CH ₂ F _{2 may} be mentioned. Further, a chlorine-based gas such as Cl ₂ may also be used. Other gases include, for example, argon, nitrogen, hydrogen, oxygen, and the like.

The substrate may, for example, be ruthenium, iridium oxide, glass, sapphire or the like.

[Examples] <Synthesis Example 1>

In a 100 ml flask, 12.0 g of phloroglucinol (manufactured by Tokyo Chemical Industry Co., Ltd.), 7.3 g of 4-hydroxybenzaldehyde (manufactured by Tokyo Chemical Industry Co., Ltd.), and methanesulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) were added. 0.59 g of propylene glycol monomethyl ether 46.5 g. Thereafter, the mixture was stirred under reflux with heating under reflux for 3 hours. After the reaction was terminated, ion exchange treatment was carried out to obtain a brownish-brown benzenetriol resin solution. The obtained polymer corresponds to the formula (1-1). The weight average molecular weight Mw measured by polystyrene conversion by GPC was 680, and the polydispersity Mw/Mn was 1.3.

<Synthesis Example 2>

25.0 g of phloroglucin (manufactured by Tokyo Chemical Industry Co., Ltd.), 25.4 g of phthalic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 151.1 g of propylene glycol monomethyl ether were placed in a 300 ml flask. Thereafter, the mixture was stirred under reflux with heating under reflux for 2 hours. After the reaction was terminated, ion exchange treatment was carried out to obtain a brownish-brown benzenetriol resin solution. The obtained polymer corresponds to the formula (1-2). The weight average molecular weight Mw measured by polystyrene conversion by GPC was 2,400, and the polydispersity Mw/Mn was 1.6.

<Synthesis Example 3>

Styrene 7.0g (manufactured by Tokyo Chemical Industry Co., Ltd.), hydroxyethyl group After lysing 8.7 g (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.79 g of 2,2'-azobisisobutyronitrile, and 38.6 g of propylene glycol monomethyl ether acetate, the solution was heated and stirred at 85 ° C. About 20 hours. The obtained polymer corresponds to the above formula (1-3). The weight average molecular weight Mw measured by polystyrene in terms of polystyrene was 9,700.

<Synthesis Example 4>

8.0 g of carbazole (manufactured by Tokyo Chemical Industry Co., Ltd.), 28.0 g of 1-naphthaldehyde (manufactured by Tokyo Chemical Industry Co., Ltd.), and p-toluenesulfonic acid monohydrate (Tokyo Chemical Industry Co., Ltd.) were added to a 100 ml eggplant type flask. 3.6 g, toluene (manufactured by Kanto Chemical Co., Ltd.), 143.8 g. Thereafter, the inside of the flask was replaced with nitrogen, heated, and stirred under reflux for about 27 hours. After the completion of the reaction, it was diluted with 90.5 g of tetrahydrofuran (manufactured by Kanto Chemical Co., Ltd.). The diluted solution was dropped into 2000 ml of methanol to cause reprecipitation. The precipitate obtained by filtration was suctioned, and the filtrate was washed with methanol, and then dried under reduced pressure at 85 ° C overnight to obtain 37.9 g of a novolak resin. The obtained polymer corresponds to the formula (1-4). The weight average molecular weight Mw measured by polystyrene in terms of polystyrene was 3,800.

<Equivalent to the surface roughening material preparation example of the composition (a3)>

0.66 g of the resin obtained in Synthesis Example 1 was added to an organic cerium oxide gel (manufactured by Nissan Chemical Industries Co., Ltd. [trade name] PGM-ST, the dispersing agent was propylene glycol monomethyl ether, and the concentration of cerium oxide was 30%. %, average particle diameter is 10 to 15 nm), 0.37 g, tetramethoxymethyl glycol urea 0.13 g, propylene glycol monomethyl ether 26.2 g, and propylene glycol monomethyl ether acetate 2.6 g. Solution. Thereafter, the mixture was filtered using a 0.2 μm polyethylene microfiltration membrane to prepare a solution of the composition (a3-1).

<Equivalent to the surface roughening material preparation of the composition (a3)>

0.64 g of the resin obtained in Synthesis Example 2 was added to an organic cerium oxide gel (manufactured by Nissan Chemical Industries Co., Ltd. [trade name] PGM-ST, dispersant was propylene glycol monomethyl ether, and cerium oxide concentration was 30 masses. %, an average particle diameter of 10-15 nm) 0.43g, tetramethoxymethylglycol urea 0.13g, propylene glycol monomethyl ether 20.4g, propylene glycol monomethyl ether acetate 8.4g, as a solution. Thereafter, filtration was carried out using a 0.2 μm polyethylene microfiltration membrane to prepare a solution of the composition (a3-2).

<Equivalent to the surface roughening material preparation example 3 of the composition (a3)>

0.64 g of the resin obtained in Synthesis Example 3 was added to an organic cerium oxide gel (manufactured by Nissan Chemical Industries Co., Ltd. [trade name] PGM-ST, dispersant was propylene glycol monomethyl ether, and cerium oxide concentration was 30 masses. %, an average particle diameter of 10-15 nm) 0.43g, tetramethoxymethylglycol urea 0.13g, propylene glycol monomethyl ether 23.3g, propylene glycol monomethyl ether acetate 5.5g, as a solution. Thereafter, filtration was carried out using a 0.2 μm polyethylene microfiltration membrane to prepare a solution of the composition (a3-3).

<Equivalent to the surface roughening material preparation of the composition (a3)>

0.65 g of the resin obtained in Synthesis Example 1 was added to an organic cerium oxide gel (product name: IPA-ST, dispersing agent manufactured by Nissan Chemical Industries Co., Ltd.) Isopropanol and cerium oxide were 30% by mass, the average particle diameter was 10 to 15 nm), 0.38 g, tetramethoxymethylglycoluric acid (0.13 g), and propylene glycol monomethyl ether (28.8 g) were used as a solution. Thereafter, filtration was carried out by using a 0.2 μm polyethylene microfiltration membrane to prepare a solution of the composition (a3-4).

<Equivalent to the surface roughening material preparation of the composition (a3)>

0.65 g of the resin obtained in Synthesis Example 1 was added to an organic cerium oxide gel (manufactured by Nissan Chemical Industries Co., Ltd. [trade name] MIBK-ST, dispersant was methyl isobutyl ketone, and cerium oxide concentration was 30. The mass%, the average particle diameter was 10 to 15 nm), 0.38 g, tetramethoxymethylglycol urea 0.13 g, and propylene glycol monomethyl ether (28.8 g) as a solution. Thereafter, filtration was carried out using a 0.2 μm polyethylene microfiltration membrane to prepare a solution of the composition (a3-5).

<Equivalent to the surface roughening material preparation of the composition (a3)>

0.65 g of the resin obtained in Synthesis Example 1 was added to an organic cerium oxide gel (manufactured by Nissan Chemical Industries Co., Ltd. [trade name] IPA-ST-L, the dispersing agent was isopropyl alcohol, and the concentration of cerium oxide was 30%. %, an average particle diameter of 40 to 50 nm), 0.38 g, tetramethoxymethylglycol urea 0.13 g, and propylene glycol monomethyl ether 28.8 g, as a solution. Thereafter, the mixture was filtered using a 0.2 μm polyethylene microfiltration membrane to prepare a solution of the composition (a3-6).

<Equivalent to the surface roughening material preparation of the composition (a3)>

0.65 g of the resin obtained in Synthesis Example 1 was added to an organic cerium oxide gel (manufactured by Nissan Chemical Industries Co., Ltd. [trade name] MIBK-ST-L, dispersed The agent is methyl isobutyl ketone, cerium oxide concentration of 30% by mass, average particle diameter of 40 to 50 nm) 0.65 g, tetramethoxymethyl glycol urea 0.13 g, and propylene glycol monomethyl ether 28.8 g. Solution. Thereafter, filtration was carried out using a 0.2 μm polyethylene microfiltration membrane to prepare a solution of the composition (a3-7).

<Example 1 of organic hard mask material constituting composition (b3)>

2 g of the resin obtained in Synthesis Example 4 was dissolved in 0.3 g of tetramethoxymethylglycoluric acid, 0.03 g of pyridinium p-toluenesulfonate, and a surfactant (made by DIC), product name: Megafac [product name] R-40, a fluorine-based surfactant, 0.002 g, 6.8 g of propylene glycol monomethyl ether acetate, and 15.8 g of propylene glycol monomethyl ether form a solution. Thereafter, filtration was carried out using a 0.2 μm polyethylene microfiltration membrane to prepare a solution of the composition (b3-1).

<Example 1>

The solution of the composition (b3-1) obtained in the organic hard mask preparation example 1 was applied onto a substrate by a spin coater, and fired at 240 ° C for 1 minute to form a 150 nm organic resin layer (B) (organic Hard mask layer). A solution of the composition (a3-1) obtained by preparing the surface roughening material on the obtained organic resin layer (B) (organic hard mask layer) was applied to the substrate by a spin coater at 240 ° C. The organic resin layer (A) (surface roughening layer) was formed by baking for 1 minute.

<Example 2>

The solution of the composition (b3-1) obtained in the organic hard mask preparation example 1 was applied onto a substrate by a spin coater, and fired at 240 ° C for 1 minute to form a 150 nm organic resin layer (B) (organic Hard mask layer). A solution of the composition (a3-2) obtained by preparing the surface roughening material on the obtained organic resin layer (B) (organic hard mask layer) was applied to the substrate by a spin coater at 240 ° C. The organic resin layer (A) (surface roughening layer) was formed by baking for 1 minute.

<Example 3>

The solution of the composition (b3-1) obtained in the organic hard mask preparation example 1 was applied onto a substrate by a spin coater, and fired at 240 ° C for 1 minute to form a 150 nm organic resin layer (B) (organic Hard mask layer). A solution of the composition (a3-3) obtained by preparing the surface roughening material on the obtained organic resin layer (B) (organic hard mask layer) was applied to the substrate by a spin coater at 240 ° C. The organic resin layer (A) (surface roughening layer) was formed by baking for 1 minute.

<Example 4>

The solution of the composition (b3-1) obtained in the organic hard mask preparation example 1 was applied onto a substrate by a spin coater, and fired at 240 ° C for 1 minute to form a 150 nm organic resin layer (B) (organic Hard mask layer). A solution of the composition (a3-4) obtained by preparing the surface roughening material on the obtained organic resin layer (B) (organic hard mask layer) was applied to the base by a spin coater. The plate was fired at 240 ° C for 1 minute to form an organic resin layer (A) (surface roughened layer).

<Example 5>

The solution of the composition (b3-1) obtained in the organic hard mask preparation example 1 was applied onto a substrate by a spin coater, and fired at 240 ° C for 1 minute to form a 150 nm organic resin layer (B) (organic Hard mask layer). A solution of the composition (a3-5) obtained by preparing the surface roughening material on the obtained organic resin layer (B) (organic hard mask layer) was applied to the substrate by a spin coater at 240 ° C. The organic resin layer (A) (surface roughening layer) was formed by baking for 1 minute.

<Example 6>

The solution of the composition (b3-1) obtained in the organic hard mask preparation example 1 was applied onto a substrate by a spin coater, and fired at 240 ° C for 1 minute to form a 150 nm organic resin layer (B) (organic Hard mask layer). A solution of the composition (a3-6) obtained by preparing the surface roughening material on the obtained organic resin layer (B) (organic hard mask layer) was applied to the substrate by a spin coater at 240 ° C. The organic resin layer (A) (surface roughening layer) was formed by baking for 1 minute.

<Example 7>

The solution of the composition (b3-1) obtained in the organic hard mask preparation example 1 was applied onto a substrate by a spin coater, and fired at 240 ° C for 1 minute to form a solution. 150 nm organic resin layer (B) (organic hard mask layer). A solution of the composition (a3-7) obtained by preparing the surface roughening material on the obtained organic resin layer (B) (organic hard mask layer) was applied to the substrate by a spin coater at 240 ° C. The organic resin layer (A) (surface roughening layer) was formed by baking for 1 minute.

<Example 8>

The solution of the composition (a3-1) obtained in the surface roughening material preparation example 1 was applied onto a substrate by a spin coater, and fired at 240 ° C for 1 minute to form an organic resin layer (A) (surface roughening layer). ).

<Comparative Example 1>

The solution of the composition (b3-1) obtained in the organic hard mask preparation example 1 was applied onto a substrate by a spin coater, and baked at 240 ° C for 1 minute to form an organic resin layer (B) (organic hard mask) Mold layer).

[Surface roughening evaluation]

The wafer on which the surface roughening layer obtained in Examples 1 to 8 was formed was etched by RIE-10NR (manufactured by Samco Co., Ltd.). The etching was performed for 90 seconds in Examples 1 to 7 using O ₂ gas as an etching gas, and etching was performed for 60 seconds in Example 8 and Comparative Example 1, and only the organic component of the surface roughened layer was preferentially etched. The organic hard mask layer was etched in Examples 1 to 7 to form a surface roughened layer.

The obtained organic resin layer (A) or the organic resin layer (A) and The surface roughened layer produced by the organic resin layer (B) was observed using a scanning electron microscope (Hitachi S-4800) (see FIGS. 1 to 5).

Similarly, the shape in which the surface generated only by the organic resin layer (B) was roughened was observed (Fig. 6).

[Base TEOS processing evaluation]

The wafer having the surface roughened layer formed of the organic resin layer (A) and the organic resin layer (B) obtained in Example 1 was etched by RIE-10NR (manufactured by Samco Co., Ltd.). Etching was performed using O ₂ gas as an etching gas for 90 seconds, and only the organic component of the surface roughening layer was preferentially etched, and the organic hard mask layer was further etched to form a surface roughened layer. Then, etching was performed for 180 seconds using C ₄ F ₈ /Ar/O ₂ gas as an etching gas, and processing of the lower TEOS (SiO ₂ film produced by the hydrolysis condensate of tetraethoxysilane) was performed.

For the obtained substrate, a scanning electron microscope (Hitachi) was used. S-4800) Observe the shape (refer to Figs. 7 to 8).

[Industry use possibility]

By the present invention, a novel method of roughening the surface of a substrate can be provided. In particular, the method of the present invention can utilize a layer in which an inorganic substance and an organic substance are mixed on a substrate, so that an etching rate of an oxygen or an acidic aqueous solution of an inorganic substance and an organic substance can be utilized to form an etching by an oxygen or an acidic aqueous solution on the surface of the substrate. a portion of the roughened layer with respect to the surface that is not etched; and further, etching the gas or an acidic aqueous solution of oxygen or a fluorine-based gas or the like with the surface roughened layer as a mask to roughen the surface of the substrate, for example, on the substrate Fine irregularities are formed. Moreover, the properties of these can be applied to a light extraction layer such as an LED.

Claims (13)

A surface roughening method comprising the steps of: a first step of applying a composition (b3) containing an organic resin (b2) on a substrate or a layer above the substrate, and drying and hardening The organic resin layer (B) is formed, and the composition (a3) containing the inorganic particles (a1) and the organic resin (a2) is further coated on the organic resin layer (B), and dried and hardened to form an organic resin layer. (A); In the second step, the surface of the same substrate is roughened by etching from above the substrate; wherein the composition (b3) further contains a crosslinking agent or a crosslinking catalyst. The surface roughening method according to claim 1, wherein the etching is performed at least once, and at least one of the etching is performed by an oxygen-based gas. The surface roughening method of claim 1, wherein the etching is performed by wet etching with an acidic aqueous solution. The surface roughening method according to claim 1, wherein the inorganic particles (a1) are metal oxide particles having an average particle diameter of 5 to 1000 nm. The surface roughening method according to the first aspect of the invention, wherein the composition (a3) contains a cerium oxide sol as an inorganic particle (a1) in which an cerium oxide is dispersed in an organic solvent, and a solution of the organic resin (a2) . The surface roughening method according to the first aspect of the invention, wherein the organic resin layer (A) contains the inorganic particles (a1) in a ratio of 5 to 50 parts by mass based on 100 parts by mass of the organic resin (a2). The surface roughening method according to the first aspect of the invention, wherein the organic resin (a2) has a repeating unit structure comprising a functional group composed of a hydroxyl group, a carboxyl group, an amine group, or a combination thereof. The surface roughening method according to the first aspect of the patent application is characterized in that the aspect ratio of the pores indicated by (height) / (diameter) formed on the substrate is in the range of 0.1 to 20. The surface roughening method according to the first aspect of the invention, wherein the organic resin layer (A) has a film thickness of 0.001 to 10 μm. The surface roughening method according to claim 1, wherein the organic resin (b2) is a resin selected from the group consisting of organic resins (a2). The surface roughening method according to the first aspect of the invention, wherein the organic resin layer (B) is a layer having a film thickness of 0.001 to 10 μm. The surface roughening method according to claim 1, wherein the composition (a3) further contains a crosslinking agent and a crosslinking catalyst. The surface roughening method according to any one of claims 1 to 12, wherein the surface roughening layer formed is a light extraction layer of the LED.