KR20200099864A - Positive-type photosensitive resin composition and insulation layer formed from the same - Google Patents

Abstract

The present invention relates to a positive-type photosensitive resin composition which exhibits excellent adhesion to a substrate despite not containing any silane coupling agents, and also exhibits excellent sensitivity, and thus improves productivity; and to an insulating film formed therefrom. In particular, the positive-type photosensitive resin composition comprises: a binder resin; a photoacid generator; and a solvent, wherein the binder resin is characterized by comprising a first resin comprising a structural unit represented by chemical formula 1. In chemical formula 1, R_1 is a hydrogen atom or a methyl group, and R_2 is a C4-C10 alkylene group.

Description

Positive photosensitive resin composition and insulating film formed therefrom TECHNICAL FIELD [POSITIVE-TYPE PHOTOSENSITIVE RESIN COMPOSITION AND INSULATION LAYER FORMED FROM THE SAME}

The present invention relates to a positive photosensitive resin composition and an insulating film formed therefrom.

In display devices such as thin film transistor (TFT) type liquid crystal display devices, inorganic protective films such as silicon nitride have been conventionally used as protective films to protect and insulate TFT (Thin Film Transistor) circuits, but dielectric constant values There is a problem in that it is difficult to improve the aperture ratio because of this high, and in order to overcome this, the demand for an organic insulating film having a low dielectric constant is increasing.

As such an organic insulating film, a photosensitive resin, which is a polymer compound whose solubility in a specific solvent is changed by chemical reaction by light and electron beams, is generally used, and the microprocessing of the circuit pattern is the polarity of the polymer caused by the photoreaction of the organic insulating film. By change and crosslinking reaction. In particular, the organic insulating film material utilizes the property of changing solubility in a solvent such as an aqueous alkali solution after exposure.

The organic insulating layer is classified into a positive type and a negative type according to the solubility of the photosensitive portion in the development. In a positive type photoresist, an exposed portion is dissolved by a developer, and in a negative type photoresist, an exposed portion is not dissolved in a developer and an unexposed portion is dissolved to form a pattern.

Among them, since the use of an aqueous alkali solution for the positive organic insulating film can exclude the use of the organic developer used in the negative organic insulating film, it is not only advantageous in terms of the work environment, but theoretically, the portion not exposed to ultraviolet rays Since swelling can be prevented, resolution is improved. In addition, after the formation of the organic film, it is easy to remove it by the stripping solution, and thus, when a defective panel occurs during the process, the organic film is removed, thereby significantly improving the recovery and reusability of the substrate.

In particular, in constructing an insulating film of a liquid crystal display as such an organic insulating film, the insulating film must have excellent insulating properties, as well as have low thermal expansion properties to reduce stress at the interface when coated on a substrate, and are physically strong. It must have characteristics and must have excellent sensitivity.

In this regard, Korean Patent Application Publication No. 10-2016-0107951 discloses (a-1) a resin in which at least a part of a phenolic hydroxyl group or a carboxyl group is protected by an acid-decomposable group, (a-2) an acrylic resin containing an epoxy group, and (a -3) (A) binder resin containing an acrylic resin containing an oxetane group; (B) mine generator; And (C) a photosensitive resin composition capable of producing an insulating film having excellent developability and sensitivity and securing stability over time by including a solvent.

In addition, Korean Patent Application Laid-Open No. 10-2010-0009801 includes a binder resin, a photoacid generator, and a solvent, and the binder resin is a polymer or copolymer containing a monomer containing an acid-decomposable acetal protecting group represented by a specific formula. It has been described with respect to a positive-type ultra-sensitive organic insulating film composition having improved sensitivity by comprising.

However, insulating films made of the composition described in the patent document have a problem in that the adhesion to the lower substrate is poor.

Republic of Korea Patent Publication No. 10-2016-0107951 (2016.09.19) Republic of Korea Patent Publication No. 10-2010-0009801 (2010.01.29)

An object of the present invention is to provide a positive photosensitive resin composition having excellent adhesion to a substrate and improved sensitivity, as to solve the above problems.

The positive photosensitive resin composition of the present invention for achieving the above object is a binder resin; Photoacid generator; And a solvent; wherein the binder resin contains a first resin including a structural unit represented by the following formula (1).

[Formula 1]

(In Formula 1,

R ₁ is a hydrogen atom or a methyl group,

R ₂ is a C4 to C10 alkylene group).

In addition, the insulating film according to the present invention is characterized by including a cured product of the above-described positive photosensitive resin composition.

Further, the image display device according to the present invention is characterized in that it includes the above-described insulating film.

The positive photosensitive resin composition of the present invention has an advantage of being able to form an insulating film with excellent sensitivity and excellent adhesion to a substrate even without a separate silane coupling agent.

In addition, the insulating film of the present invention has excellent mechanical properties due to excellent adhesion to the substrate, and improved sensitivity of the exposure process, thereby providing excellent productivity.

Further, the image display apparatus of the present invention has the same advantages as described above.

1 to 5 are schematic cross-sectional views for explaining a method of forming an insulating film according to an embodiment of the present invention.

In the present invention, when a member is positioned "on" another member, this includes not only the case where the member is in direct contact with the other member, but also the case where another member is interposed between the two members.

In the present invention, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

Hereinafter, the present invention will be described in more detail.

< Positive type Photosensitive resin composition>

The positive photosensitive resin composition according to an aspect of the present invention includes a binder resin; Photoacid generator; And a solvent; wherein the binder resin contains a first resin including a structural unit represented by the following formula (1), and thus has excellent adhesion to the substrate without including a separate silane coupling agent. Rather, there is an advantage in that productivity is improved due to excellent sensitivity.

[Formula 1]

(In Formula 1,

R ₁ is a hydrogen atom or a methyl group,

R ₂ is a C4 to C10 alkylene group).

In the present invention, the "alkylene group" refers to a divalent linear or branched hydrocarbon group consisting of carbon and hydrogen.

The positive photosensitive resin composition of the present invention may be provided as, for example, a chemically amplified resist (CAR) composition in which a difference in solubility occurs due to an acid generated by an exposure process, and quinonedia An insulating film or an insulating pattern may be formed with improved sensitivity, adhesion, and resolution compared to a photoactive compound (PAC)-based composition such as gide.

Binder resin

The positive photosensitive resin composition according to an aspect of the present invention includes a binder resin as a base component, and the binder resin serves to provide a basic skeleton of an insulating film that can be formed from a photosensitive resin composition containing the same, and an exposure process It may also provide a difference in solubility by

According to an aspect of the present invention, the binder resin includes a structural unit represented by Formula 1, that is, a first resin including a long-chain silane coupling group of C4 or more, so that the binder resin can be mixed with the substrate without additional addition of a separate silane coupling agent. Adhesion is improved, and according to an embodiment of the present invention, the substrate may exhibit better adhesion than an inorganic, for example, a silicon-based substrate. In addition, if a separate silane coupling agent is additionally added, there is a possibility that a problem may occur in storage stability, but the binder resin of the present invention has an advantage of superior storage stability since there is no need to add a separate silane coupling agent.

In Formula 1, the number of carbon atoms of R ₂ may be preferably 5 to 10, more preferably 7 to 10. When the number of carbon atoms of R ₂ is included within the above-described range, there is an advantage in that adhesion to the substrate can be further improved.

The structural unit represented by Formula 1 may be included in an amount of 5 to 60 mol%, preferably 10 to 30 mol%, and more preferably, based on 100 mol% of the total structural unit of the first resin including the same. May be included in 10 to 25 mol%. If the mole% of the structural unit represented by Formula 1 is included in less than the above range, a problem of poor adhesion may occur, and if the above range is exceeded, a problem of poor developability or reduced sensitivity may occur.

According to an embodiment of the present invention, the first resin may have more excellent curability and mechanical properties by further including a structural unit represented by the following Chemical Formula 2 or Chemical Formula 3, and developability for an alkaline solution may be further improved. There is an advantage to be able to.

[Formula 2]

[Formula 3]

(In Formulas 2 and 3,

R ₃ and R ₄ are each independently a hydrogen atom or a methyl group).

The structural unit represented by Formula 2 may be included in an amount of 5 to 30 mol%, preferably 5 to 25 mol%, and more preferably, based on 100 mol% of the total structural unit of the first resin including the same. May be included in 5 to 15 mol%. When the mole% of the structural unit represented by Formula 2 is contained in less than the above range, a problem of deteriorating developability may occur, and when the above range is exceeded, the residual film rate of the non-exposed portion is decreased or adhesion is reduced. Can occur.

The structural unit represented by Formula 3 may be included in an amount of 10 to 70 mol%, preferably 20 to 60 mol%, and more preferably, based on 100 mol% of the total structural unit of the first resin including the same. May be included in 30 to 60 mol%. If the mole% of the structural unit represented by Formula 3 is contained below the above range, a reliability problem may occur in a post-process, and if it exceeds the above range, developability may decrease or sensitivity may decrease. .

According to an embodiment of the present invention, the first resin may further include an oxetane group-containing acrylic structural unit, and in this case, there is an advantage in that a thermal curing process by a crosslinking reaction can be accelerated through an oxetane group.

In addition, according to an embodiment of the present invention, the oxetane group-containing acrylic structural unit may be a structural unit derived from a monomer represented by the following formula (4).

[Formula 4]

(In Chemical Formula 4,

R ₅ is a hydrogen atom or a methyl group,

R ₆ is a direct bond or a C1 to C6 alkylene group,

R ₇ is a C1 to C6 alkyl group).

In the present invention, the'alkyl group' refers to a monovalent linear or branched hydrocarbon group consisting of carbon and oxygen.

When the oxetane group-containing acrylic structural unit is further included as described above, the oxetane group-containing acrylic structural unit may be included in an amount of 10 to 40 mol% based on 100 mol% of the total first resin including the oxetane group-containing acrylic structural unit. When the mole% of the acrylic structural unit containing the oxetane group is contained within the above range, there is an advantage in that adhesion is further improved, and the degree of curing by thermal curing is improved, thereby improving reliability in a post process.

The weight average molecular weight of the above-described first resin may be 2,000 to 30,000, preferably 5,000 to 20,000, and when the weight average molecular weight satisfies the above range, developability and aging stability may be improved, and the film residue after development Can be reduced.

According to an embodiment of the present invention, the binder resin may further include a second resin including a phenolic or novolac resin protected with an acid-decomposable group or a third resin including an acrylic resin.

The second resin may include a plurality of hydroxy groups, and at least some of the hydroxy groups may be protected by an acid-decomposable group. For example, among the phenol units included in the second resin, a hydroxy group included in at least some of the phenol units may be protected by the acid-decomposable group.

According to an embodiment of the present invention, the second resin may include a structural unit represented by Chemical Formula 5 below.

[Formula 5]

(In Chemical Formula 5,

R ₈ and R ₉ are each independently a hydrogen atom or a methyl group,

R ₁₀ represents an acid-decomposable group, a C1 to C6 linear or branched alkyl group, a tetrahydropyranyl group, a C1 to C6 alkoxy group and a C4 to C8 cycloalkoxy group

It is selected from the group consisting of,

a is 40 to 80 mol%,

b is 20 to 60 mol%).

In Formula 5, a and b may represent a molar ratio of a phenol unit and a phenol unit protected by an acid-decomposable group, respectively. For example, a may be 40 to 80 mol%, and b may be 20 to 60 mol%. The a and b represent the relative molar ratio of the phenol unit and the phenol unit protected by the acid-decomposable group, and the addition of other units is not excluded.

According to an embodiment of the present invention, the second resin may include a structural unit represented by Formula 5-1 below.

[Chemical Formula 5-1]

(In Formula 5-1,

R ₈ and R ₉ are each independently a hydrogen atom or a methyl group,

R ₁₁ and R ₁₂ are each independently a C1 to C6 alkyl group,

a is 40 to 80 mol%,

b is 20 to 60 mol%).

For example, the phenol unit may be derived from hydroxy styrene as the first monomer. The phenol unit protected by the acid-decomposable group may be derived from a second monomer represented by Formula 5-2 or 5-3 below.

[Formula 5-2]

[Chemical Formula 5-3]

(In Chemical Formulas 5-2 and 5-3, R ₁₀ to R ₁₂ are as defined in Chemical Formulas 5 and 5-1).

The second resin may be prepared through a copolymerization reaction of the first monomer and the second monomer, and the number of moles of the first monomer and the second monomer may be adjusted to correspond to a desired molar ratio represented by a and b. .

As described above, the second resin includes a phenol unit in which a hydroxy group remains and a phenol unit in which the hydroxy group is protected by an acid-decomposable group together, so that sensitivity to the exposure process and adhesion to the substrate may be realized.

The second resin may be prepared by copolymerizing other monomers commonly used in the art capable of forming a binder resin in addition to the above-described monomer.

The weight average molecular weight of the second resin may be 5,000 to 35,000, preferably 5,000 to 20,000. Within the above range, the residual film ratio of the photosensitive composition may be effectively improved, and film residue may be reduced.

Since the third resin includes an epoxy-containing acrylic resin, for example, thermosetting properties are improved in a heat treatment process such as post-baking, and mechanical properties such as heat resistance and impact resistance of the insulating film can be further improved. .

According to an embodiment of the present invention, the third resin may be derived from a monomer represented by the following Formula 6 or Formula 7.

[Chemical Formula 6]

[Formula 7]

(In Chemical Formulas 6 and 7,

R ₁₆ is hydrogen or a methyl group,

R ₁₇ is a C1 to C6 alkylene group,

R ₁₈ and R ₁₉ are each independently a hydrogen atom or a C1 to C6 alkyl group, or are linked to each other to form a C3 to C8 ring,

c is an integer from 1 to 6).

The monomer represented by Formula 6 may form an ether bond through an oxygen atom adjacent to R ₁₇ . Therefore, since rotation through the ether bond is possible, the glass transition temperature is reduced, thereby improving the flowability of the photosensitive composition.

In addition, the length of the monomer may be adjusted through the adjustment of c in Formula 6. The slope of the sidewall of the insulating pattern generated after the development process may be adjusted by adjusting the length of the monomer. For example, when a subsequent conductive pattern such as a transparent electrode is formed by reducing the slope of the sidewall, damage to the insulating pattern and dropping of the conductive pattern may be prevented.

When the third resin includes a structural unit derived from a monomer represented by Chemical Formula 7, the transmittance of the third resin may be further improved.

The third resin may be prepared by copolymerizing other monomers commonly used in the art capable of forming an acrylic resin in addition to the monomer represented by Formula 6 or Formula 7.

For example, the third resin may be prepared by copolymerizing at least one of a monomer represented by Formula 6 or Formula 7 and other monomers described above. The molar ratio of the structural unit derived from the monomer represented by Formula 6 or Formula 7 may be about 5 to 60 mol% with respect to the total 100 mol% of the third resin including the same, but is not limited thereto. When the molar ratio is included within the above range, there is an advantage in that it is easier to improve developability, transparency, and pattern slope of the photosensitive resin composition including the third resin.

The weight average molecular weight of the third resin may be 5,000 to 40,000, preferably 7,000 to 30,000. In the above range, developability may be further improved and film residue may be reduced.

The other monomers of the second resin and the third resin may independently include an ethylenically unsaturated monomer containing a carboxyl group to improve developability and adhesion to the substrate. As examples of the carboxy group-containing ethylenically unsaturated monomer, monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid; Dicarboxylic acids such as fumaric acid, mesaconic acid, and itaconic acid, and anhydrides thereof.

The other monomers are, for example, styrene, vinyltoluene, methylstyrene, p-chlorostyrene, o-methoxystyrene, m-methoxystyrene, p-methoxystyrene, o-vinylbenzylmethylether, m-vinylbenzyl Aromatic vinyl compounds such as methyl ether and p-vinyl benzyl methyl ether; N-cyclohexylmaleimide, N-benzylmaleimide, N-phenylmaleimide, No-hydroxyphenylmaleimide, Nm-hydroxyphenylmaleimide, Np-hydroxyphenylmaleimide, No-methylphenylmaleimide, Nm -N-substituted maleimide compounds such as methylphenylmaleimide, Np-methylphenylmaleimide, No-methoxyphenylmaleimide, Nm-methoxyphenylmaleimide, and Np-methoxyphenylmaleimide; Methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, alkyl (meth)acrylates such as sec-butyl (meth)acrylate and t-butyl (meth)acrylate; Cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-methylcyclohexyl (meth)acrylate,, 2-dicyclopentanyloxyethyl (meth)acrylate, isobornyl (meth)acrylate, etc. Alicyclic (meth)acrylates; Aryl (meth)acrylates such as phenyl (meth)acrylate and benzyl (meth)acrylate; 3-(methacryloyloxymethyl)oxetane, 3-(methacryloyloxymethyl)-3-ethyloxetane, 3-(methacryloyloxymethyl)-2-trifluoromethyloxetane, 3-(methacryloyloxymethyl)-2-phenyloxetane, 2-(methacryloyloxymethyl)oxetane, 2-(methacryloyloxymethyl)-4-trifluoromethyloxetane, etc. Unsaturated oxetane compounds and the like are mentioned, but are not limited thereto, and these may be used alone or in combination of two or more.

The binder resin of the present invention may be a mixture in which a second resin or a third resin is further included in the aforementioned first resin. In this case, 5 to 60 parts by weight of the first resin and about 40 to 95 parts by weight of the second resin or the third resin may be included with respect to 100 parts by weight of the binder resin.

According to an embodiment of the present invention, the binder resin may be a mixture of the above-described first resin, second resin, and third resin. According to an embodiment of the present invention, in this case, 5 to 60 parts by weight of the first resin, 30 to 70 parts by weight of the second resin, and 10 to 40 parts by weight of the third resin are included with respect to 100 parts by weight of the binder resin. I can. When the content of the first resin satisfies the above range, the adhesion of the formed pattern may be improved while maintaining excellent developability.

When the content of the second resin satisfies the above range, the sensitivity to the exposure process and the adhesion to the substrate may be improved together, and when the content of the third resin satisfies the above range, the thermosetting property is improved in the heat treatment process, There is an advantage that mechanical properties such as heat resistance and impact resistance of the insulating film can be further improved.

According to an embodiment of the present invention, the content of the entire binder resin is 5 to 55% by weight, preferably 10 to 50% by weight, more preferably, based on 100% by weight of the total positive photosensitive resin composition including the same. It may be included in 15 to 40% by weight. When the content of the binder resin is included within the above range, the sensitivity for the exposure process and the resolution for the development process may be further improved.

Photoacid generator

The positive photosensitive resin composition according to an aspect of the present invention is a CAR type composition including a photoacid generator.

The photoacid generator is a compound that generates an acid (for example, proton (H ⁺ )) by an exposure process using ultraviolet rays or radiation, and a compound known in the field of photosensitive compositions may be used without particular limitation.

For example, the photoacid generator is diazonium salt, phosphonium salt, sulfonium salt, iodonium salt, imide sulfonate, oxime sulfonate, diazodisulfone, disulfone, ortho-nitrobenzyl Sulfonate-based, triazine-based compounds, etc. may be included. These can be used alone or in combination of two or more.

The content of the photoacid generator may be, for example, about 0.01 to 20 parts by weight, and preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the binder resin. Sufficient sensitivity to the exposure process may be obtained without inhibiting transmittance and mechanical properties through the binder resin and the antioxidant that may be further included within the above range.

In addition, a sensitizer may be used together with the photoacid generator to improve the sensitivity of the exposure process. For example, the acid production from the photoacid generator can be amplified by the sensitizer.

For example, the sensitizer is polynuclear aromatics, xanthenes, xanthones, cyanines, oxonols, thiazines, acridines, acridons, anthraquinones, squaliums, styryls, base styryls, Coumarins, anthracene compounds, and the like may be included, but are not limited thereto. These may be used alone or in combination of two or more.

In addition, the sensitizer may include, for example, a compound represented by Formula 8 below.

[Formula 8]

(In Chemical Formula 8,

R ₂₀ and R ₂₁ are each independently a C1 to C6 linear or branched alkyl group).

In addition, the sensitizer may further include at least one of the compounds represented by the following Formulas 8-1 to 8-3 in that the sensitivity can be improved.

[Chemical Formula 8-1]

[Formula 8-2]

[Chemical Formula 8-3]

The content of the sensitizer may be about 0.01 to 20 parts by weight, and preferably about 0.5 to 10 parts by weight, based on 100 parts by weight of the binder resin included together. When the content of the sensitizer is included within the above range, sensitivity to the exposure process may be improved without impairing the effect of improving transmittance.

menstruum

In the positive photosensitive resin composition of the present invention, an organic solvent having sufficient solubility in organic components such as the above-described binder resin and antioxidant can be used as the solvent.

As the organic solvent, for example, ethers, acetates, esters, ketones, amides, and lactones may be used, and these may be used alone or in combination of two or more.

Examples of the ether solvent include ethylene glycol monoalkyl ether, ethylene glycol dialkyl ether, propylene glycol monoalkyl ether, propylene glycol dialkyl ether, diethylene glycol dialkyl ether, dipropylene glycol monoalkyl ether, dipropylene glycol di Alkyl ether, etc. are mentioned.

Examples of the acetate solvent include ethylene glycol monomethyl ether acetate, ethylene glycol monoalkyl ether acetate, propylene glycol monoalkyl ether acetate, diethylene glycol monoalkyl ether acetate, dipropylene glycol monoalkyl ether acetate, propylene glycol dialkyl acetate, etc. Can be mentioned.

Examples of the ester solvent include ethyl hydroxyacetate, ethyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-3-methylbutyrate, ethyl methoxyacetate, ethyl ethoxyacetate, methyl 3-methoxypropionate , 3-methoxyethylpropionate, 3-ethoxymethylpropionate, 3-ethoxyethylpropionate, 3-methoxybutylacetate, 3-methyl-3-methoxybutylacetate, 3-methyl-3-methoxybutylpro Cypionate, 3-methyl-3-methoxybutyl butyrate, methyl acetoacetate, ethyl acetoacetate, methyl pyrbate, ethyl pyrbate, and diethylene glycol methyl ethyl ester.

Examples of the ketone solvents include methyl ethyl ketone, methyl propyl ketone, methyl-n-butyl ketone, methyl isobutyl ketone, 2-heptanone, 3-heptanone, 4-heptanone, and cyclohexanone.

Examples of the amide solvent include N-methylformamide, N,N-dimethylformamide, N-methylacetamide, N,N-dimethylacetamide, and N-methylpyrrolidone. Lactone solvent As an example, γ-butyrolactone is mentioned.

Preferably, propylene glycol methyl ether acetate, diethylene glycol methyl ethyl ester, or a mixture thereof may be used in terms of coating properties and uniformity of the thickness of the insulating film, but are not limited thereto, and each of them alone or two or more It can also be mixed and used.

The solvent may be included in a residual amount excluding all components included together. For example, the content of the solvent may be 40 to 90% by weight, and preferably about 50 to 80% by weight, based on 100% by weight of the total positive photosensitive resin composition including the same. By properly maintaining the content and viscosity of the solid content within the above range, it is possible to further improve the coatability of the composition.

additive

The positive photosensitive resin composition according to an embodiment of the present invention may further include, for example, an additive within a range that does not inhibit the interaction of each component described above, and the additive may be an antioxidant.

Antioxidant

When the positive photosensitive resin composition of the present invention further includes an antioxidant, there is an advantage in that the binder resin can be inhibited from denaturation and oxidation due to oxidation.

The antioxidant may be included in the form of a monomer, and may function as a protecting agent for a phenol unit or a hydroxy group that may be included in the binder resin.

The antioxidant may include a bifunctional epoxy compound. For example, the antioxidant may have a structure in which epoxy groups are bonded at the end by a linker group.

According to an embodiment of the present invention, the antioxidant may include a compound represented by the following formula (9).

[Formula 9]

(In Chemical Formula 9,

R ₂₂ is a C1 to C6 alkylene group or a C3 to C12 cycloalkylene group).

The alkylene group may be a divalent hydrocarbon group and may be a straight chain or branched chain, and in the case of a branched chain, the number of carbon atoms may be 3 to 6.

According to an embodiment of the present invention, the antioxidant may include a compound represented by Formula 9-1 below.

[Chemical Formula 9-1]

The antioxidant is, for example, a post-baking process after the exposure and development process, or a phenol unit generated by the release of an acid-decomposable group in a post-baking process or a subsequent heat treatment process after the exposure and development process, and is oxidized, for example, modified into quinone. Can be prevented. When the binder resin is modified to contain quinone, a yellowish phenomenon of the insulating film may be caused, so that the transmittance of the insulating film may be reduced.

For example, the antioxidant may be bonded to a hydroxy group exposed to the phenol unit after the exposure and development process through an epoxy group to inhibit oxidation modification to the quinone unit. Accordingly, desired transparency and transmittance of the insulating layer may be maintained even after the post-baking or subsequent heat treatment process.

Since the antioxidant includes, for example, an epoxy group at each end through a linear linker, the hydroxy group of the adjacent binder resin can be easily met without steric hindrance. When the length of the linear linker is excessively increased, the possibility of reaction or interaction with the hydroxy group may be reduced due to molecular folding or the like. In addition, when the antioxidant has an epoxy function of 3 or more, the possibility of binding to the hydroxy group of the binder resin may decrease as the molecular structure becomes bulky.

As described above, the antioxidant may improve adhesion of the composition by interacting with the hydroxy group contained in the binder resin. In addition, as shown in Chemical Formula 7, for example, the flowability of the composition is improved through a rotatable structure of an ether bond such as an ethylene oxide (EO) group, and accordingly, film formation properties such as coatability and flatness may be improved. I can.

The content of the antioxidant may be about 0.01 to 30 parts by weight, preferably about 1 to 10 parts by weight based on 100 parts by weight of the binder resin. When the content of the antioxidant is included within the above range, the above-described transmittance and adhesion of the insulating film can be effectively improved.

In addition, the additive may include a basic compound, a surfactant, a coupling agent, a thermal crosslinking agent, a light stabilizer, a photocuring accelerator, a leveling agent, an antifoaming agent, etc. In addition, compounds commonly used in the field of a positive photosensitive resin composition can be used. have.

The basic compound may be included to control developability, for example, and may include an aliphatic amine, an aromatic amine, a heterocyclic amine, a quaternary ammonium hydroxide, a quaternary ammonium salt of a carboxylic acid, and the like.

The surfactant may improve adhesion between the substrate and the photosensitive composition.

The surfactant may include a fluorine-based surfactant, a nonionic surfactant, a cationic surfactant, an anionic surfactant, a silicone surfactant, and the like, which are widely known in the art. These may be used alone or in combination of two or more.

The coupling agent may be included to improve adhesion between the photosensitive composition and a substrate including an inorganic material, and to adjust the taper angle of the insulating pattern.

The coupling agent may include, for example, a silane coupling agent or a thiol-based compound, and preferably a silane coupling agent may be used.

Examples of the silane coupling agent include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrialkoxysilane, γ-glycidoxypropylalkyldialkoxysilane, γ-methacryl Oxypropyltrialkoxysilane, γ-methacryloxypropylalkyldialkoxysilane, γ-chloropropyltrialkoxysilane, γ-mercaptopropyltrialkoxysilane, β-(3,4-epoxycyclohexyl)ethyltrialkoxysilane, Vinyl trialkoxysilane, etc. are mentioned.

As a composition, the thermal crosslinking agent may further improve the degree of crosslinking of the insulating film through a heat treatment process such as post baking, thereby improving hardness and heat resistance.

The thermal crosslinking agent may include, for example, a polyacrylate resin, an epoxy resin, a phenol resin, a melamine resin, an organic acid, an amine compound, an anhydride compound, and the like.

The light stabilizer may improve the light resistance of the photosensitive composition comprising the same. The light stabilizer may include, for example, a benzotriazole-based, triazine-based, benzophenone-based, hindered aminoether-based, or hindered amine-based compound.

The content of the above-described additives may be appropriately changed in consideration of the process conditions, and the scope thereof is not particularly limited in the present invention, but may be included in, for example, 0.01 to 10 parts by weight based on 100 parts by weight of each binder resin, and preferably May be included in an amount of 0.1 to 5 parts by weight.

<Insulation film>

Another aspect of the present invention is an insulating film containing a cured product of the above-described positive photosensitive resin composition.

1 to 5 are schematic cross-sectional views for explaining a method of forming an insulating film according to an embodiment of the present invention.

Referring to FIG. 1, a first conductive pattern 110 may be formed on a substrate 100.

In this case, the substrate 100 may be, for example, a glass substrate, a resin substrate including polyimide, polymethyl methacrylate (PMMA), or a silicone substrate, and according to an embodiment of the present invention, the When the substrate is a silicone-based substrate, there is an advantage in that adhesion with the positive photosensitive resin composition of the present invention can be further improved. The substrate 100 may also be, for example, a display panel substrate of an image display device.

The first conductive pattern 110 may be formed by depositing a transparent conductive oxide such as metal or ITO to form a first conductive layer and then etching the first conductive layer.

Before forming the first conductive pattern 110, a silicon-based barrier layer including silicon oxide, silicon nitride, silicon oxynitride, or the like may be formed on the upper surface of the substrate 100.

The first conductive pattern 110 may be provided as an electrode such as a gate electrode, a source electrode, or a drain electrode of a thin film transistor (TFT) included in an image display device, and the first conductive pattern 110 is It may be provided by wiring such as a scan line, a data line, or a power line of the image display device.

Referring to FIG. 2, a preliminary insulating layer 120 covering the first conductive pattern 110 may be formed on the substrate 100. The preliminary insulating layer 120 may be formed by applying the above-described photosensitive composition through a spin coating, slit coating, roll coating process, or the like, and then performing a drying and/or soft baking process. For example, the soft baking process may be performed in a temperature range of about 60 to 150°C.

As described above, the insulating film of the present invention includes the cured product of the above-described positive photosensitive resin composition, and the composition contains the first resin containing the structural unit of Formula 1, thereby having excellent adhesion to the substrate 100 In addition, when the composition further includes a bifunctional epoxy compound as an antioxidant, the flowability of the composition may be improved, and thus film flatness or coating properties may be further improved.

Referring to FIG. 3, the preliminary insulating layer 120 may be converted into an insulating layer including the exposed portion 123 and the non-exposed portion 125 through an exposure process.

After disposing a mask including a light blocking part and a transmitting part on the preliminary insulating film 120, excimer laser, far ultraviolet rays, ultraviolet rays, visible rays, electron rays, X-rays or g-rays (wavelength 436 nm), i- Light such as a line (wavelength 365 nm) and h-line (wavelength 405 nm) can be irradiated.

For example, the transmissive portion of the mask may overlap the first conductive pattern 110, and a portion of the preliminary insulating layer 120 irradiated with light through the transmissive portion may be converted into the exposure unit 123.

Acid is generated from the photoacid generator included in the photosensitive composition by the exposure process, and acid-decomposable groups that may be included in the binder resin (for example, the first resin) may be released. Accordingly, the hydroxy group of the phenol unit protected by the acid-decomposable group is exposed, so that the solubility of the exposed portion 123 in the developer may increase.

In order to prevent diffusion of acid generated after the exposure process, a post exposure baking (PEB) process may be further performed.

Referring to FIG. 4, the exposed portion 123 may be removed by performing a developing process. Accordingly, an insulating pattern may be defined by the remaining non-exposed portion 125. The developing process may be performed using, for example, an alkali developer such as tetramethylammonium hydroxide (TMAH).

An opening 127 for at least partially exposing the first conductive pattern 110 may be formed in a space where the exposed portion 123 is removed by the developing process.

After the development process, a post-baking process may be further performed to improve mechanical properties through additional hardening of the insulating pattern (eg, the remaining unexposed portion 125). The post baking process may be performed at a temperature of about 150 to 350°C.

When high-temperature heat treatment such as the post-baking process is performed, phenol units that may be included in the binder resin may be oxidized (for example, in quinone units), resulting in yellowing of the insulating pattern, but the bifunctional epoxy system By further including a compound, the phenol unit may be protected to suppress yellowing, thereby maintaining the transmittance of the insulating pattern.

Referring to FIG. 5, a second conductive pattern 130 may be formed in the opening 127 illustrated in FIG. 4.

For example, after forming a second conductive film including a metal or transparent conductive oxide on the non-exposed portion 125 while sufficiently filling the opening 127, the second conductive pattern 130 is formed by patterning the second conductive film. Can be,

Even when a heat treatment process such as a high-temperature deposition process is performed to form the second conductive film, a bifunctional epoxy-based compound is further included as in the embodiment of the present invention to prevent yellowing and dropping of the non-exposed part 125. I can suppress it more.

The second conductive pattern 130 may be provided as, for example, a pixel electrode of an image display device, or may be provided as various wiring structures. For example, the second conductive pattern 130 may be provided as a pixel electrode including a via structure penetrating the insulating pattern to be electrically connected to the first conductive pattern 110. In this case, the first conductive pattern 110 may be provided as a drain electrode connected to the pixel electrode.

<Image display device>

Another aspect of the present invention is an image display device including the above-described insulating film. The insulating layer may be provided as a gate insulating layer, an interlayer insulating layer, a via insulating layer, or the like of the image display device. According to an embodiment of the present invention, the insulating layer may be an interlayer insulating layer or a via insulating layer. For example, the second conductive pattern 130 shown in FIG. 5 is provided as a pixel electrode, and a display layer including a liquid crystal layer or an organic light-emitting layer is formed on the second conductive pattern 130 to form an LCD device or an OLED. Devices and the like can be implemented.

A counter electrode (eg, a cathode) facing the pixel electrode may be disposed on the display layer, and additional structures such as an encapsulation layer, a hard coating layer, and a window substrate may be stacked on the counter electrode. .

The image display device of the present invention has the advantage of suppressing yellowing caused by heat treatment by including the above-described insulating film, thereby improving image quality by showing excellent transparency, excellent durability, and not causing defects in process.

Hereinafter, preferred examples are presented to aid in understanding the present invention, but the following examples are only illustrative of the present invention, and that various changes and modifications are possible within the scope of the present invention and the scope of the technical idea are obvious to those skilled in the art. , It is natural that such modifications and modifications fall within the appended claims. In the following Examples and Comparative Examples, "%" and "parts" indicating the content are based on weight unless otherwise specified.

Example And Comparative example : Positive type Preparation of photosensitive resin composition

A positive photosensitive resin composition was prepared according to each composition and content shown in Table 1 below.

division Binder resin (A) Photoacid generator (B) Photosensitizer (C) Antioxidant (D) Solvent (E) Basic compound (F) Surfactant (G) Silane coupling agent (H) Kinds Parts by weight Parts by weight Parts by weight Parts by weight Kinds Parts by weight Parts by weight Parts by weight Parts by weight Example 1 A1-1 10 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 Example 2 A1-1 20 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 Example 3 A1-1 30 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 Example 4 A1-1 40 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 Example 5 A1-1 50 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 Example 6 A1-2 10 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 Example 7 A1-2 20 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 Example 8 A1-2 50 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 Example 9 A1-2 40 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 Example 10 A1-1 45 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 A4 20 Example 11 A1-1 35 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 A4 20 Example 12 A1-2 45 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 A4 20 Example 13 A1-2 35 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 A4 20 Example 14 A1-1 100 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 A4 20 Example 15 A1-2 100 0.02 0.01 0.1 E1 100 0.001 0.001 - A2 50 E2 150 A4 20 Comparative Example 1 A2 50 0.02 0.01 0.1 E1 100 0.001 0.001 0.04 A3 50 E2 150 Comparative Example 2 A2 50 0.02 0.01 0.1 E1 100 0.001 0.001 0.04 A3 40 E2 150 A4 10 Comparative Example 3 A2 50 0.02 0.01 0.1 E1 100 0.001 0.001 0.04 A4 50 E2 150 Comparative Example 4 A2 50 0.02 0.01 0.1 E1 100 0.001 0.001 0.04 E2 150

In Table 1, detailed contents for each configuration are as follows.

A) Binder resin

A1-1) p1/p2/p3 = 20/30/50 (mol%)

A1-2) p1/p2/p4/p3 = 10/30/30/30 (mol%)

A2) p5/p6 = 60/40 (mol%)

A3) p7/p8/p9 = 50/30/20

A4) a/b/c/d = 25/18/42/15

B) Photoacid generator

C) Photosensitizer

D) antioxidant

E) solvent

E-1) Propylene glycol methyl ether acetate

E-2) Diethylene glycol methyl ethyl ether

F) Basic compound: dicyclohexylmethylamine

G) Surfactant: SH-8400 (manufactured by Dow Corning)

H) Silane coupling agent: γ-glycidoxypropyltrialkoxysilane

Experimental example 1. Sensitivity measurement

On a 0.7mm-thick glass substrate (Corning 1737, Corning), the photosensitive resin composition of each of the above Examples and Comparative Examples was coated with a spinner, and the solvent was volatilized by heating on a hot plate at 100° C. for 125 seconds, and a thickness of 4.0 μm The photosensitive resin composition layer of was formed.

Thereafter, in order to obtain a contact hole pattern having a diameter of 10 μm, exposure was performed with a Mask Aligner (Karl suss, MA6) using a mask having a square pattern opening having a side of 10 μm in the exposed portion.

The substrate after exposure was puddle-developed with a developer in a 2.38% tetramethylammonium hydroxide aqueous solution at 23°C for 60 seconds, and heated in an oven at 230°C for 30 minutes to obtain a cured film (pattern).

Thereafter, the substrate was cut vertically, and the exposure amount to be a 10 μm contact hole in each composition was selected as sensitivity, and the results are shown in Table 2 below.

Experimental example 2. Pattern angle measurement

The pattern obtained by the same method as in Experimental Example 1 was cut vertically, the angle with respect to the substrate was calculated from an optical photograph, and the results are shown in Table 2 below.

If the pattern angle is out of the range of 30 to 70°, the resolution may be deteriorated during the thermal curing process, or problems such as short circuiting or lifting of the electrode may occur during the post process.

Experimental example 3. Adhesion evaluation

The photosensitive resin composition of the Example and Comparative Example was applied with a spinner on the glass substrate on which the silicon nitride film (SiNx) was deposited, without applying the HMDS solution, and heated on a hot plate at 100° C. for 125 seconds to volatilize the solvent. , To form a photosensitive resin composition layer having a thickness of 4.0 μm. After that, using a mask having a 5-20 μm dot pattern, exposure was performed with a Mask Aligner (Karl suss, MA6). The substrate after exposure was puddle-developed for 60 seconds at 23° C. with a 2.38% tetramethylammonium hydroxide aqueous solution as a developer, and the pattern was checked for peeling. At this time, the evaluation criteria are as follows, and the evaluation results are shown in Table 2 below.

<Evaluation criteria>

◎: 5 to 20 µm hole patterns are not peeled off

○: 5 µm hole pattern partial peeling

△: more than 5㎛ 10㎛ or less hole pattern peeling

×: more than 10 µm and 15 µm or less hole pattern peeling

Experimental example 4. Stability evaluation over time

The photosensitive resin compositions prepared in Examples and Comparative Examples were stored in an incubator at 23° C. for a week to observe changes in adhesion, and after evaluation based on the following evaluation criteria, the results are shown in Table 2 below.

<Evaluation criteria>

◎: 5 to 20 µm hole patterns are not peeled off

○: 5 µm hole pattern partial peeling

△: more than 5㎛ 10㎛ or less hole pattern peeling

×: more than 10 µm and 15 µm or less hole pattern peeling

division Sensitivity (mJ/cm ² ) Pattern angle (°) Adhesion Sincerity Example 1 24 46 ◎ ◎ Example 2 22 43 ◎ ◎ Example 3 24 52 ◎ ◎ Example 4 22 50 ◎ ◎ Example 5 22 58 ◎ ◎ Example 6 24 55 ○ ○ Example 7 24 59 ○ ○ Example 8 22 56 ○ ○ Example 9 24 52 ◎ ◎ Example 10 22 43 ◎ ◎ Example 11 24 46 ◎ ◎ Example 12 23 47 ○ ○ Example 13 24 44 ○ ○ Example 14 22 43 ◎ ◎ Example 15 26 47 ○ ○ Comparative Example 1 28 27 × × Comparative Example 2 26 32 × × Comparative Example 3 27 26 × × Comparative Example 4 34 33 × ×

Referring to Table 2, in the case of Examples 1 to 15 containing the structural units presented in the present invention, Comparative Examples 1 to 4 containing no structural units presented in the present invention, and a separate silane coupling agent. It can be confirmed that the sensitivity is more excellent, the pattern angle is formed well within the range of 30 to 70°, and the adhesion or stability over time is excellent.

100: substrate 10: first conductive pattern
120: preliminary insulating film 123: exposed portion
125: non-exposed portion 127: opening
130: second conductive pattern

Claims (17)

Binder resin; Photoacid generator; And a solvent; including,
The binder resin is a positive photosensitive resin composition, characterized in that it contains a first resin containing a structural unit represented by the following formula (1):
[Formula 1]

(In Formula 1,
R ₁ is a hydrogen atom or a methyl group,
R ₂ is a C4 to C10 alkylene group). The method of claim 1,
The first resin is a positive photosensitive resin composition, characterized in that it further comprises a structural unit represented by the following formula (2) or (3):
[Formula 2]

[Formula 3]

(In Formulas 2 and 3,
R ₃ and R ₄ are each independently a hydrogen atom or a methyl group). The method of claim 2,
The first resin is a positive photosensitive resin composition, characterized in that it further comprises an oxetane group-containing acrylic structural unit. The method of claim 3,
The oxetane group-containing acrylic structural unit is a positive photosensitive resin composition, characterized in that it is derived from a monomer represented by the following formula (4):
[Formula 4]

(In Chemical Formula 4,
R ₅ is a hydrogen atom or a methyl group,
R ₆ is a direct bond or a C1 to C6 alkylene group,
R ₇ is a C1 to C6 alkyl group). The method of claim 1,
The binder resin is a second resin containing a phenolic or novolac resin protected by an acid-decomposable group; Or a third resin comprising an acrylic resin; a positive photosensitive resin composition further comprising a. The method of claim 5,
The second resin is a positive photosensitive resin composition, characterized in that it comprises a structural unit represented by the following formula (5):
[Formula 5]

(In Chemical Formula 5,
R ₈ and R ₉ are each independently a hydrogen atom or a methyl group,
R ₁₀ represents an acid-decomposable group and is selected from the group consisting of a C1 to C6 straight or branched alkyl group, a tetrahydropyranyl group, a C1 to C6 alkoxy group, and a C4 to C8 cycloalkoxy group,
a is 40 to 80 mol%,
b is 20 to 60 mol%). The method of claim 6,
The second resin is a positive photosensitive resin composition, characterized in that it comprises a structural unit represented by the following formula 5-1:
[Chemical Formula 5-1]

(In Formula 5-1,
R ₈ and R ₉ are each independently a hydrogen atom or a methyl group,
R ₁₁ and R ₁₂ are each independently a C1 to C6 alkyl group,
a is 40 to 80 mol%,
b is 20 to 60 mol%). The method of claim 5,
The third resin is a positive photosensitive resin composition, characterized in that derived from a monomer represented by the following formula 6 or 7:
[Formula 6]

[Formula 7]

(In Chemical Formulas 6 and 7,
R ₁₆ is hydrogen or a methyl group,
R ₁₇ is a C1 to C6 alkylene group,
R ₁₈ and R ₁₉ are each independently a hydrogen atom or a C1 to C6 alkyl group, or are linked to each other to form a C3 to C8 ring,
c is an integer from 1 to 6). The method of claim 1,
The binder resin is a positive type photosensitive resin composition, characterized in that it is contained in an amount of 5 to 55% by weight, based on 100% by weight of the total positive photosensitive resin composition comprising the same. The method of claim 5,
Positive type, characterized in that the first resin is 5 to 60 parts by weight, the second resin is 30 to 70 parts by weight, and the third resin is 10 to 40 parts by weight based on 100 parts by weight of the total binder resin. Photosensitive resin composition. The method of claim 1,
The positive type photosensitive resin composition further comprises an additive containing an antioxidant. The method of claim 11,
The antioxidant is a positive photosensitive resin composition comprising a compound represented by the following formula (9):
[Formula 9]

(In Chemical Formula 9,
R ₂₂ is a C1 to C6 alkylene group or a C3 to C12 cycloalkylene group). The method of claim 12,
The antioxidant is a positive photosensitive resin composition, characterized in that it comprises a compound represented by the following formula 9-1:
[Chemical Formula 9-1]

An insulating film comprising a cured product of the positive photosensitive resin composition according to any one of claims 1 to 13. The method of claim 14,
The insulating film, wherein the insulating film is an interlayer insulating film or a via insulating film of an image display device. The method of claim 14,
The insulating film is an insulating film, characterized in that laminated on a silicon-based substrate. An image display device comprising the insulating film of claim 14.

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