JP2023166903A - Underfill material for micro led display devices, underfill film, method for producing underfill film, and micro led display device - Google Patents

Abstract

To provide an underfill material that has photosensitivity, flux functionality, and adhesiveness, and can be patterned to form a film solely on required areas of an array substrate, which enables mass transfer of LED devices and efficient metal bonding.SOLUTION: A thermosetting positive photosensitive adhesive composition contains the following component (A), component (B), component (C) and component (D). Component (A): an alkali-soluble resin that includes a phenolic hydroxy group and has a polymeric glass transition temperature (Tg) of 60°C or lower. Component (B): a crosslinker. Component (C): a photosensitizer with quinonediazide. Component (D): a solvent.SELECTED DRAWING: None

Description

The present invention relates to an underfill material for a micro LED display element, an underfill film, a method for manufacturing an underfill film, and a micro LED display element, and in particular, an underfill material used for a micro LED display element, a method for manufacturing an underfill film, The present invention relates to an underfill film obtained by the manufacturing method and a micro LED display element using the underfill film.

Currently, liquid crystal display devices (LCD) and organic light emitting diode display devices (OLED) are mainly used in flat panel displays used in mobile phones, monitors, and TVs. Although LCDs have well-established mass production technology and are inexpensive and can be made large, they are inferior in form factor and flexibility because they require the use of a backlight for display. Further, although OLEDs have excellent flexibility, there is a problem in that increasing the brightness of the display element shortens the lifespan. As a display element capable of solving these drawbacks, a micro LED display element has been developed in recent years, in which inorganic light emitting diodes are arranged on each pixel of an array substrate to display a display. Since micro-LED display elements use micrometer-sized inorganic light-emitting diodes as light-emitting sources, they can achieve higher brightness than LCDs and OLEDs, have high color purity, and have a long lifespan. Furthermore, since LEDs are arranged for each pixel, each pixel can be made independent, and it is highly flexible.

The LED element of the light emitting source is supplied as small pieces by, for example, epitaxially growing a semiconductor layer on a sapphire substrate to form electrodes, and then dicing. Micro LED display elements require the LED elements manufactured in this way to be arranged on an array substrate with high precision. As a method of arranging LED elements on an array substrate, a pick & place method in which each LED element is installed one by one has been considered so far. However, this method is not suitable for mass production because it requires a huge amount of time to install the LEDs.

Therefore, in recent years, a large number of LED elements have been picked up from a sapphire substrate at once using an adhesive base material (stamp), mass transferred to an array substrate, and then the LED elements are thermocompression bonded to the electrodes of the array substrate using a bonding head, or by laser bonding. A stamp method for metal joining by heating has been proposed (Non-Patent Documents 1 and 2). By using this method, a large number of LED elements can be arranged on the array substrate at one time and bonded to the array substrate, so it is expected that the throughput will be significantly improved compared to the Pick & Place method.

Adv. Optical Mater. 2015, 3, 1313-1335 SID 2017 DIGEST, 257

As described above, the mass transfer method using a stamp has the potential to significantly improve throughput compared to the pick & place method in which LED elements are arranged one by one on an array substrate.
However, this method mass-transfers the LED elements from the sapphire substrate to the array substrate due to the difference in adhesiveness between the array substrate and the LED elements and the adhesiveness between the stamp and the LED elements. A membrane with On the other hand, when a film is formed on an array substrate for mass transfer, a problem has arisen in that it is difficult to take out wiring afterwards.

In addition, when mass-transferred LED elements are metal-bonded to an array substrate by thermocompression bonding or laser heating, if an oxide film is formed on the array substrate or the electrodes of the LED elements, metal bonding may not be possible and conduction defects may occur. Are known. Therefore, when bonding LED elements, a flux treatment to remove the metal oxide film is usually required before bonding.

Therefore, the present invention makes it possible to improve the efficiency of mass transfer and metal bonding of LED elements by forming a film only at necessary locations on the array substrate by patterning, which has photosensitivity, flux properties, and adhesive properties. The purpose is to provide underfill materials that

Another object of the present invention is to provide an underfill film patterned on an array substrate, which makes it possible to improve the efficiency of mass transfer and metal bonding of LED elements using the underfill material.

Furthermore, an object of the present invention is to provide a method for manufacturing an underfill film that makes it possible to improve the efficiency of mass transfer and metal bonding of LED elements using the underfill material.

An object of the present invention is to provide a micro LED display element equipped with an underfill film that enables efficient mass transfer and metal bonding of the LED element.

The present inventor conducted extensive research to solve the above problems, and as a result, discovered the present invention. That is, the present invention relates to the following.
1. A positive photosensitive adhesive composition containing the following (A) component, (B) component, (C) component, and (D) solvent.
(A) Component: Alkali-soluble resin having a phenolic hydroxyl group and having a glass transition temperature (Tg) of the polymer of 60°C or lower (B) Component: Crosslinking agent (C) Component: Photosensitive agent (D) having a quinonediazide ) Ingredients: Solvent 2. 2. The positive photosensitive adhesive composition according to 1, wherein the component (A) is a polymer containing a structural unit derived from a monomer (A2) whose homopolymer has a Tg of 0° C. or less.
3. The component (A) contains, as a constituent component, a monomer (A1) having a phenolic hydroxyl group and a polymerizable unsaturated group, and a constituent unit derived from a monomer (A2) whose homopolymer has a Tg of 0°C or less. 2. The positive photosensitive adhesive composition according to 2, which is an acrylic polymer.
4. The monomer (A1) having a phenolic hydroxyl group and a polymerizable unsaturated group is selected from p-hydroxystyrene, m-hydroxystyrene, α-methyl-p-hydroxystyrene, and a compound represented by the following formula (1). 3. The positive photosensitive adhesive composition according to 3, which is selected from the group consisting of:
In formula (1), P represents a (meth)acrylic group, a (meth)acrylamide group, an N-methyl (meth)acrylamide group, or a maleimide group, and b ₁ is a single bond or a straight chain having 1 to 12 carbon atoms. , branched or cyclic, and a combination thereof, c ₁ represents a single bond, -O-, -COO-, or -OCO-, and d ₁ represents a substituted or unsubstituted hydroxyphenyl group. .
5. 5. The positive photosensitive adhesive composition according to any one of 3 to 4, wherein the monomer (A2) that makes the homopolymer have a Tg of 0° C. or less is a compound represented by the following formula (2).
In formula (2), R ₂ represents a hydrogen atom or a methyl group, a ₂ represents an oxygen atom or a sulfur atom, and b ₂ is a linear, branched, or cyclic chain having 2 to 20 carbon atoms, or a combination thereof. It represents an alkylene group, and -CH ₂ - in the alkylene group may be replaced with an oxygen atom, provided that they are not adjacent to each other. c ₂ represents a single bond, -O-, -COO-, or -OCO-, and d ₂ represents a hydrogen atom or a hydroxyl group.
6. Any of 1 to 5, wherein the component (A) is an acrylic polymer further containing as a component a structural unit derived from a monomer (A3) containing an aromatic hydrocarbon group represented by the following formula (3) The positive photosensitive adhesive composition according to item (1).
In formula (3), R ₃ represents a hydrogen atom or a methyl group, a ₃ represents an oxygen atom, a sulfur atom, -NH-, or -N(CH ₃ )-, and b ₃ represents a single bond or the number of carbon atoms Represents an alkylene group consisting of 1 to 20 linear, branched, or cyclic, or a combination thereof, and -CH ₂ - in the alkylene group may be replaced with an oxygen atom, provided that they are not adjacent to each other. . c ₃ represents a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -N(CH ₃ )CO-, or -CON(CH ₃ )-, and d ₃ represents carbon Represents 6 to 10 substituted or unsubstituted aromatic hydrocarbon groups.
7. 7. The positive photosensitive adhesive composition according to any one of 1 to 6, wherein the component (B) is 5 to 60 parts by mass relative to 100 parts by mass of the component (A).
8. 8. The positive photosensitive adhesive composition according to any one of 1 to 7, wherein the component (C) is 10 to 100 parts by mass relative to 100 parts by mass of the component (A).
9. The positive photosensitive adhesive according to any one of 1 to 8, further containing 0.01 to 1.0 parts by mass of a surfactant as component (E) based on 100 parts by mass of component (A). Composition.
10. A cured film obtained by curing the positive photosensitive adhesive composition according to any one of items 1 to 9.
11. An LED display element having the cured film described in 10 as an underfill material.

The positive photosensitive adhesive composition of the present invention has photosensitivity, flux properties, and adhesive properties, and by patterning to form a film only at necessary locations on the array substrate, mass transfer of LED elements and metal bonding are possible. It is possible to form an underfill material that makes it possible to improve efficiency.

The positive photosensitive adhesive composition of the present invention is a positive photosensitive adhesive composition containing the following components (A), (B), (C), and (D) solvent.
(A) Component: Alkali-soluble resin having a phenolic hydroxyl group and having a glass transition temperature (Tg) of the polymer of 60°C or lower (B) Component: Crosslinking agent (C) Component: Photosensitive agent (D) having a quinonediazide ) Component: Solvent The details of each component will be explained below.

<(A) component>
Component (A) is an alkali-soluble resin having a phenolic hydroxyl group and having a glass transition temperature (Tg) of the polymer of 60° C. or lower. The alkali-soluble resin is preferably an acrylic polymer.

In the present invention, acrylic polymer refers to a monomer having a polymerizable unsaturated group such as acrylic ester, methacrylic ester, styrene, maleimide, etc., that is, a polymerizable group containing a carbon-carbon double bond in its structure. Refers to the resulting polymer.
The alkali-soluble resin of component (A) is preferably an alkali-soluble acrylic polymer, and there are no particular limitations on the main chain skeleton and the type of side chains of the polymer constituting the acrylic polymer.

If the alkali-soluble resin of component (A) has a too small weight average molecular weight of less than 20,000, the alkali resistance will decrease in the alkaline development step of lithography, and the desired pattern may not be formed. If the average molecular weight is too large, exceeding 150,000, a residue may remain during development. From the viewpoint of patterning properties, the weight average molecular weight of the alkali-soluble resin is preferably in the range of 20,000 to 150,000, more preferably in the range of 30,000 to 100,000.

The method for synthesizing the alkali-soluble resin of component (A) is to use a monomer containing a monomer (A1) having a phenolic hydroxyl group and a polymerizable unsaturated group, and a monomer (A2) whose homopolymer has a Tg of 0°C or less. A method of copolymerizing a mixture is simple. Here, the homopolymer refers to a polymer consisting of (A2) monomer alone, and can be obtained by a polymerization reaction at a temperature of 50 to 110°C in a solvent in which a polymerization initiator or the like is optionally coexisting. , (A2) A polymer having a weight average molecular weight of 3000 or more obtained by irradiating ultraviolet rays and causing a polymerization reaction in a state in which a monomer, a photoradical generator, etc. coexist.

Details regarding the constituent monomers of component (A) will be described below.
The monomer (A1) is a monomer having a phenolic hydroxyl group and a polymerizable unsaturated group, and is preferably p-hydroxystyrene, m-hydroxystyrene, α-methyl-p-hydroxystyrene, and a monomer represented by the following formula (1). At least one monomer selected from the compounds represented.
In formula (1), P represents a (meth)acrylic group, a (meth)acrylamide group, an N-methyl(meth)acrylamide group, or a maleimide group, preferably a (meth)acrylic group. b ₁ represents a single bond, or a linear, branched, or cyclic alkylene group having 1 to 12 carbon atoms, or a combination thereof, and is preferably a single bond or a linear alkylene group having 1 to 6 carbon atoms. . c ₁ represents a single bond, -O-, -COO-, or -OCO-, preferably a single bond or -O-. d ₁ represents a substituted or unsubstituted hydroxyphenyl group, preferably p-hydroxyphenyl group. Substituents for the hydroxyphenyl group include a halogen atom, an alkyl group having 1 to 3 carbon atoms, an alkenyl group having 2 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, and a fluoroalkyl group having 1 to 3 carbon atoms. , a fluoroalkenyl group having 2 to 3 carbon atoms, a fluoroalkoxy group having 1 to 3 carbon atoms, an alkyloxycarbonyl group having 2 to 3 carbon atoms, a cyano group, a nitro group, and the like. By having these hydroxyphenyl groups, component (A) not only becomes alkali-soluble but also exhibits flux properties.

Examples of the monomer (A1) include p-hydroxystyrene, α-methyl-p-hydroxystyrene, N-(p-hydroxyphenyl)maleimide, N-(p-hydroxyphenyl)acrylamide, N-(p-hydroxyphenyl) ) Methacrylamide, p-hydroxyphenyl acrylate, p-hydroxyphenyl methacrylate, etc., which can be used alone or in combination of two or more. Among these, monomers selected from p-hydroxyphenyl acrylate and p-hydroxyphenyl methacrylate are preferred.

The monomer (A2) is a monomer whose homopolymer has a Tg of 0° C. or less, and is preferably a compound represented by the following formula (2).
In formula (2), R ₂ represents a hydrogen atom or a methyl group. _a2 represents an oxygen atom or a sulfur atom, preferably an oxygen atom. Represents an alkylene group consisting of a straight chain, branched, or cyclic having 2 to 20 carbon atoms, or a combination thereof, preferably an alkylene group consisting of a straight chain, branched, or cyclic having 2 to 12 carbon atoms, or a combination thereof, More preferably, it is a straight chain or branched alkylene group having 2 to 12 carbon atoms. Note that -CH ₂ - in the alkylene group of b ₂ may be replaced with an oxygen atom, provided that they are not adjacent to each other. c ₂ represents a single bond, -O-, -COO-, or -OCO-, preferably a single bond or -O-. d ₂ represents a hydrogen atom or a hydroxyl group.

Specifically, the monomer (A2) includes ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-hexyl methacrylate, n- Heptyl acrylate, n-heptyl methacrylate, n-octyl acrylate, n-octyl methacrylate, nonyl acrylate, nonyl methacrylate, isononyl acrylate, isononyl methacrylate, lauryl acrylate, lauryl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl acrylate, 3-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, ethyl carbitol acrylate, glycidyl acrylate, methoxytriethylene glycol acrylate, methoxytriethylene glycol methacrylate, 2-methoxyethyl acrylate, 2-methoxyethyl methacrylate, 2-ethoxyethyl acrylate, 2-ethoxyethyl methacrylate, tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 3-methoxybutyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, etc., which may be used alone or in combination of two or more. can be used, but is not limited to these.

From the viewpoint of suitably obtaining the effects of the present invention, the structural units derived from the monomer (A1) in component (A) are equal to the total of the structural units derived from the monomer (A1) and the structural units derived from the monomer (A2). The constituent units derived from the monomer (A2) in component (A) are preferably 10 to 50% by mass based on the sum of the constituent units derived from the monomer (A1) and the monomer (A2). It is preferably contained in an amount of 50 to 90% by mass.

Further, in the present invention, when obtaining the acrylic polymer of component (A), it is preferable to contain a monomer (A3) containing an aromatic hydrocarbon group represented by the following formula (3).
In formula (3), R ₃ represents a hydrogen atom or a methyl group. a ₃ represents an oxygen atom, a sulfur atom, -NH-, or -N(CH ₃ )-, preferably an oxygen atom or -NH-, and more preferably an oxygen atom. b ₃ is a single bond, or an alkylene group consisting of a linear, branched, or cyclic group having 1 to 20 carbon atoms, or a combination thereof, preferably a linear, branched, or cyclic group having 2 to 12 carbon atoms, or a combination thereof. It is an alkylene group consisting of, more preferably a linear alkylene group having 2 to 8 carbon atoms. Note that non-adjacent --CH ₂ -- in the alkylene group of b ₃ may be replaced with oxygen atoms, provided that they are not adjacent to each other. c ₃ represents a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -N(CH ₃ )CO-, or -CON(CH ₃ )-, preferably a single bond , -O-, -COO-, or -OCO-, more preferably a single bond or -O-. d ₃ represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, preferably a substituted or unsubstituted phenyl group. Examples of substituents on the aromatic hydrocarbon group include halogen atoms, alkyl groups having 1 to 3 carbon atoms, alkenyl groups having 2 to 3 carbon atoms, alkoxy groups having 1 to 3 carbon atoms, and fluorocarbon groups having 1 to 3 carbon atoms. Examples include an alkyl group, a fluoroalkenyl group having 2 to 3 carbon atoms, a fluoroalkoxy group having 1 to 3 carbon atoms, an alkyloxycarbonyl group having 2 to 3 carbon atoms, a cyano group, and a nitro group. When component (A) contains a structural unit derived from a monomer having an aromatic hydrocarbon group shown in formula (3) as a structural component, the alkali resistance of the unexposed area improves in the development step after exposure, and when patterned. The contrast ratio can be improved.

Specific examples of the monomer (A3) include 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, phenyl acrylate, phenyl methacrylate, 4-methylphenyl acrylate, 4-methylphenyl methacrylate, 3-phenoxypropyl acrylate, 3-phenoxypropyl Methacrylate, 4-phenoxybutyl acrylate, 4-phenoxybutyl methacrylate, 6-phenoxyhexyl acrylate, 8-phenoxyoctyl acrylate, 2-phenoxypropyl 2-methyl-2-propenoate, 2-(1-methyl-2-phenoxy) Ethoxy)ethyl 2-methyl-2-propenoate, benzyl acrylate, benzyl methacrylate, 4-ethoxybenzyl methacrylate, naphthyl acrylate, naphthyl methacrylate, etc. These can be used alone or in combination of two or more, but are not limited to these. It doesn't mean you can't do it. Among them, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, phenyl acrylate, phenyl methacrylate, 4-methylphenylacrylate, 3-phenoxypropyl acrylate, 3-phenoxypropyl methacrylate, 4-phenoxybutyl acrylate, 4-phenoxybutyl methacrylate, Benzyl methacrylate is preferred.

When component (A) contains a structural unit derived from monomer (A3), from the viewpoint of suitably obtaining the effects of the present invention, component (A) contains a structural unit derived from monomer (A1) and monomer (A2). ) is 40 to 100% by mass of the total of the structural units derived from monomer (A1), the structural units derived from monomer (A2), and the structural units derived from monomer (A3). It is preferably 40 to 80% by weight, more preferably 50 to 70% by weight. The structural units derived from the monomer (A3) in component (A) are relative to the total of the structural units derived from the monomer (A1), the structural units derived from the monomer (A2), and the structural units derived from the monomer (A3). It is preferably 0 to 60% by weight, more preferably 20 to 60% by weight, and even more preferably 30 to 50% by weight.

Further, in the present invention, when obtaining the acrylic polymer of component (A), other monomers that can be copolymerized with the above monomers (A1) to (A3) can be used in combination. Specific examples of the above-mentioned other monomers include acrylic ester compounds, methacrylic ester compounds, maleimide, acrylamide compounds, acrylonitrile, styrene compounds, and vinyl compounds. Specific examples of the other monomers will be listed below, but the invention is not limited to these.

Examples of the acrylic ester compounds include methyl acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methyl-2-adamantyl acrylate, anthryl acrylate, anthryl methyl acrylate, 2,2,2-trifluoroethyl acrylate, Examples include 2-aminoethyl acrylate, 2-propyl-2-adamantyl acrylate, caprolactone 2-(acryloyloxy)ethyl ester, and poly(ethylene glycol)ethyl ether acrylate.

Examples of the methacrylic acid ester compounds include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, n-pentyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, and 2-methyl methacrylate. -2-adamantyl methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, anthryl methacrylate, anthryl methyl methacrylate, 2,2,2-trifluoroethyl methacrylate, 2-aminomethyl methacrylate, γ-butyrolactone methacrylate , 2-propyl-2-adamantyl methacrylate, caprolactone 2-(methacryloyloxy)ethyl ester, poly(ethylene glycol) ethyl ether methacrylate, and the like.

Examples of the acrylamide compound include N-methylacrylamide, N-methylmethacrylamide, N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N-methoxymethylacrylamide, N-methoxymethylmethacrylamide, N-butoxy Examples include methylacrylamide, N-butoxymethylmethacrylamide, and the like.

Examples of the vinyl compounds include methyl vinyl ether, benzyl vinyl ether, cyclohexyl vinyl ether, vinylnaphthalene, vinylanthracene, vinylcarbazole, allyl glycidyl ether, 3-ethenyl-7-oxabicyclo[4.1.0]heptane, 1,2 -epoxy-5-hexene, 1,7-octadiene monoepoxide and the like.

Examples of the styrene compound include styrene having no hydroxyl group, such as styrene, α-methylstyrene, chlorostyrene, and bromostyrene.

The method for obtaining the alkali-soluble resin used in the present invention is not particularly limited, but for example, monomer (A1) and monomer (A2), optionally monomer (A3) and other monomers mentioned above, and optionally a polymerization initiator, etc. are allowed to coexist. It is obtained by carrying out a polymerization reaction in a solvent at a temperature of 50 to 110°C. At that time, the solvent used is not particularly limited as long as it dissolves the monomer and alkali-soluble resin that constitute the alkali-soluble resin. Specific examples include the solvents listed in (D) Solvent below.

The alkali-soluble resin (hereinafter also referred to as a specific copolymer) obtained in this manner is usually in the form of a solution dissolved in a solvent.

In addition, the solution of the specific copolymer obtained as described above is poured into diethyl ether, water, etc. under stirring to cause reprecipitation, and the resulting precipitate is filtered and washed, and then under normal pressure or reduced pressure. By drying at room temperature or by heating, powder of the specific copolymer can be obtained. By such an operation, the polymerization initiator and unreacted monomer coexisting with the specific copolymer can be removed, and as a result, purified powder of the specific copolymer can be obtained. If sufficient purification cannot be achieved in one operation, the obtained powder may be redissolved in a solvent and the above operation may be repeated.
In the present invention, the powder of the above-mentioned specific copolymer may be used as it is, or the powder may be redissolved in, for example, the below-mentioned solvent (D) and used in the form of a solution.
Further, in the present invention, the alkali-soluble resin of component (A) may be a mixture of multiple types of specific copolymers.

<(B) component>
Component (B) is a crosslinking agent, and more specifically, it is a compound having a structure that can form a crosslinked structure through a thermal reaction with component (A). Specific examples will be given below, but the invention is not limited to these. The thermal crosslinking agent is preferably selected from, for example, (B1) a crosslinkable compound represented by formula (4) or formula (5) described below, and (B2) a crosslinking agent having an isocyanurate skeleton. These crosslinking agents can be used alone or in combination of two or more.

As component (B1), a crosslinkable compound represented by formula (4) or formula (5) can be contained.
In formula (4), k is an integer of 2 to 10, m is an integer of 0 to 4, and X ₄ represents a k-valent organic group. A plurality of m may be the same or different.
In formula (5), k is an integer of 2 to 10, and X ₅ represents a k-valent organic group.

Component (B1) is not particularly limited as long as it is a compound having a cycloalkene oxide structure represented by formula (4) or a compound having a glycidyl structure represented by formula (5). Specific examples thereof include the following formulas E-2-1 and E-2-2, and the commercial products shown below.

Commercially available products include Epolead GT-401, Epolead GT-403, Epolead GT-301, Epolead GT-302, Celloxide 2021, Celloxide 3000 (product name manufactured by Daicel Corporation), and Denacol EX-, an alicyclic epoxy resin. 252 (product name manufactured by Nagase Chemtechs Co., Ltd.), CY175, CY177, CY179 (product names manufactured by CIBA-GEIGY A.G.), Araldite CY-182, CY-192, CY-184 (product names manufactured by CIBA-GEIGY A.G.) CIBA-GEIGY (product name manufactured by A.G.), Epiclon 200, 400 (product name manufactured by DIC Corporation), Epicort (product name manufactured by Yuka Shell Epoxy Co., Ltd.), ED-5661, ED- 5662 (trade name manufactured by Celanese Coating Co., Ltd.), Epocalic DE-102, DE-103 (manufactured by ENEOS Co., Ltd.), jER152, 871, 872 (manufactured by Mitsubishi Chemical Co., Ltd.), OGSOL -CG500 (manufactured by Osaka Gas Chemical Co., Ltd.) and the like. Moreover, these crosslinkable compounds can be used alone or in combination of two or more types.

Among these, those represented by the above formulas E-2-1 and E-2-2 have a cyclohexene oxide structure from the viewpoint of heat resistance, solvent resistance, process resistance such as long-term baking resistance, and transparency. The compounds Epolead GT-401, Epolead GT-403, Epolead GT-301, Epolead GT-302, Celoxide 2021, Celoxide 3000, Epocalic DE-102, and Epocalic DE-103 are preferred.

When component (B1) is selected as the crosslinking agent, the content is 10 to 60 parts by weight, preferably 10 to 50 parts by weight, and more preferably 20 to 40 parts by weight based on 100 parts by weight of component (A). It is.

Further, the positive photosensitive adhesive composition of the present invention can contain a compound having an isocyanurate skeleton as the component (B2). Examples of compounds having an isocyanurate skeleton and two or more polymerizable unsaturated double bonds include trimethallyl isocyanurate, tris(2-acryloyloxyethyl)isocyanurate, and tris(2-methacryloyloxyethyl)isocyanurate. Compounds having an isocyanurate skeleton such as and two or more polymerizable unsaturated double bonds, and isocyanurate skeletons such as triglycidyl isocyanurate, TEPIC-FL, TEPIC-VL (all manufactured by Nissan Chemical Co., Ltd.) Examples include compounds having two or more epoxy moieties. When these compounds having an isocyanurate skeleton are included in the positive photosensitive adhesive composition of the present invention, the adhesion of the mass-transferred LED chip is improved, so there is a possibility that process defects in the mass transfer process can be reduced. .

These compounds can be used alone or in combination of two or more

The content of component (B2) in the positive photosensitive adhesive composition of the present invention is preferably 5 to 60 parts by mass, more preferably 10 to 50 parts by mass, based on 100 parts by mass of component (A). .

<(C) component>
Component (C) is a photosensitizer containing quinonediazide, preferably a photosensitizer containing 1,2-naphthoquinonediazide. A quinonediazide compound is a compound that has either a hydroxyl group or an amino group, or both a hydroxyl group and an amino group, and the hydroxyl group or amino group (if it has both a hydroxyl group and an amino group, the total amount of them) ), a compound in which preferably 10 to 100 mol%, particularly preferably 20 to 95 mol%, is esterified or amidated with quinonediazide sulfonic acid can be used.

Examples of the above-mentioned compounds having a hydroxyl group include phenol, o-cresol, m-cresol, p-cresol, hydroquinone, resorcinol, catechol, methyl gallic acid, ethyl gallic acid, 1,3,3-tris(4-hydroxyphenyl) Butane, 2,2-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 4,4'-dihydroxyphenylsulfone, 4,4-hexafluoroisopropylidenediphenol, 1, 1,1-tris(4-hydroxyphenyl)ethane, 4,4'-[1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethylidene]bisphenol, 2,4-dihydroxy Benzophenone, 2,3,4-trihydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2',3,4,4' -Phenol compounds such as pentahydroxybenzophenone, 2,5-bis(2-hydroxy-5-methylbenzyl)benzene, ethanol, 2-propanol, 4-butanol, cyclohexanol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol , 2-methoxyethanol, 2-butoxyethanol, 2-methoxypropanol, 2-butoxypropanol, ethyl lactate, butyl lactate, and other aliphatic alcohols.

In addition, the compounds containing the above amino group include aniline, o-toluidine, m-toluidine, p-toluidine, 4-aminodiphenylmethane, 4-aminodiphenyl, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine. , 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, and other anilines, and aminocyclohexane.

Furthermore, examples of compounds containing both a hydroxyl group and an amino group include o-aminophenol, m-aminophenol, p-aminophenol, 4-aminoresorcinol, 2,3-diaminophenol, 2,4-diaminophenol, 4,4'-diamino-4''-hydroxytriphenylmethane, 4-amino-4',4''-dihydroxytriphenylmethane, bis(4-amino-3-carboxy-5-hydroxyphenyl)ether, bis (4-amino-3-carboxy-5-hydroxyphenyl)methane, 2,2-bis(4-amino-3-carboxy-5-hydroxyphenyl)propane, 2,2-bis(4-amino-3-carboxy Examples include aminophenols such as -5-hydroxyphenyl)hexafluoropropane, and alkanolamines such as 2-aminoethanol, 3-aminopropanol, and 4-aminocyclohexanol.

These quinonediazide compounds can be used alone or in combination of two or more.

The content of component (C) in the positive photosensitive adhesive composition of the present invention is preferably 10 to 100 parts by mass, more preferably 15 to 50 parts by mass, and more preferably 15 to 50 parts by mass, based on 100 parts by mass of component (A). Preferably it is 20 to 40 parts by mass. When the amount is less than 10 parts by mass, the difference in dissolution rate in the developer between the exposed area and the unexposed area of the positive photosensitive adhesive composition becomes small, and patterning by development may be difficult. In addition, if it exceeds 100 parts by mass, the quinonediazide compound may not be sufficiently decomposed by short exposure, resulting in decreased sensitivity, or component (C) may absorb light, reducing the transparency of the cured film. It may be stored away.

<(D) Solvent>
The solvent (D) used in the present invention dissolves the components (A), (B), and (C), and also dissolves the component (E) described below, which is added as desired. The type and structure of the solvent are not particularly limited as long as it has a suitable dissolving ability.

Examples of such solvent (D) include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol. Monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-butanone, 3-methyl-2-pentanone, 2-pentanone, 2-heptanone, γ-butyrolactone, 2-hydroxypropion ethyl acid, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropion ethyl acid, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2 - Examples include pyrrolidone.

These solvents can be used alone or in combination of two or more.
Among these (D) solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, 2-heptanone, propylene glycol propyl ether, propylene glycol propyl ether acetate, ethyl lactate, butyl lactate, etc. have good coating properties and are safe. This is preferable from the viewpoint of high These solvents are commonly used as solvents for photoresist materials.

<(E) component>
Component (E) is a surfactant. The positive photosensitive adhesive composition of the present invention may further contain a surfactant for the purpose of improving its coating properties, as long as it does not impair the effects of the present invention.

The surfactant as component (E) is not particularly limited, but examples thereof include fluorosurfactants, silicone surfactants, and nonionic surfactants. As this type of surfactant, commercially available products such as those manufactured by 3M Japan Ltd., DIC Corporation, or AGC Seimi Chemical Co., Ltd. can be used. These commercial products are convenient because they are easily available. Specific examples include Polyfox PF-136A, 151, 156A, 154N, 159, 636, 6320, 656, 6520 (manufactured by Omnova), Megafac R30, R08, R40, R41, R43, F251, F477. , F552, F553, F554, F555, F556, F557, F558, F559, F560, F561, F562, F563, F565, F567, F570 (manufactured by DIC Corporation), FC4430, FC4432 (manufactured by 3M Japan Ltd.), Asahi Guard AG710, Surflon S-386, S-611, S-651, (manufactured by AGC Seimi Chemical Co., Ltd.), Ftergent FTX-218, DFX-18, 220P, 251, 212M, 215M (manufactured by Neos Co., Ltd.) ), fluorine-based surfactants such as BYK-300, 302, 306, 307, 310, 313, 315, 320, 322, 323, 325, 330, 331, 333, 342, 345, 346, 347, 348, 349 , 370, 377, 378, 3455 (manufactured by BIC Chemie Japan Co., Ltd.), SH3746, SH3749, SH3771, SH8400, SH8410, SH8700, SF8428 (manufactured by Toray Dow Corning Silicone Co., Ltd.), KF-351, KF- Silicone surfactants such as 352, KF-353, KF-354L, KF-355A, KF-615A, KF-945, KF-618, KF-6011, KF-6015 (manufactured by Shin-Etsu Chemical Co., Ltd.) Can be mentioned.
The surfactants (E) can be used alone or in combination of two or more.

When a surfactant is used, its content is usually 0.01 to 1.0 parts by weight, preferably 0.02 to 0.8 parts by weight, based on 100 parts by weight of component (A). .

<Other additives>
Furthermore, the positive photosensitive resin composition of the present invention may optionally contain rheology modifiers, pigments, dyes, storage stabilizers, antifoaming agents, or polyhydric phenols, as long as the effects of the present invention are not impaired. It may contain a solubility promoter such as a polyhydric carboxylic acid. Furthermore, the positive photosensitive adhesive composition of the present invention may further contain a fluxing agent for the purpose of assisting the fluxing effect of component (A), as long as it does not impair the effects of the present invention. Examples of the fluxing agent include nitrogen-containing compounds having lone pairs of electrons (imidazoles, amines, etc.), carboxylic acids, phenols, alcohols, and the like. Specific examples include carboxylic acids such as 8-quinolinol, malonic acid, succinic acid, maleic acid, glutaric acid, suberic acid, adipic acid, and sebacic acid, ethylenediamine, 2methylimidazole, 2ethylimidazole, 2phenylimidazole, Alkylbenzimidazole (Tough Ace F2 series: Shikoku Kasei), diphenylguanidine hydrobromide, cyclohexylamine hydrobromide, diethylamine hydrochloride, triethanolamine hydrobromide, monoethanolamine hydrobromide etc.

<Positive photosensitive adhesive composition>
The positive photosensitive resin composition of the present invention comprises a copolymer obtained by copolymerizing components (A) (A1) to (A2) and optionally (A3), a crosslinking agent (B), ( The 1,2-quinonediazide compound of component C) is dissolved in the solvent of (D), and further contains one or more of the surfactants and other additives of component (E), if desired. It is a composition that allows

The solid content in the positive photosensitive adhesive composition of the present invention is not particularly limited as long as each component is uniformly dissolved in the solvent, but is, for example, 1 to 80% by mass, and for example 5 to 60% by weight, or 10 to 50% by weight. Here, the solid content refers to all the components of the positive photosensitive adhesive composition excluding (D) the solvent.

The method for preparing the positive photosensitive adhesive composition of the present invention is not particularly limited, but for example, component (A) (alkali-soluble resin) is dissolved in (D) solvent, and this solution is added to ( (E ) component (surfactant) and other additives are further added and mixed.

In preparing the positive-working photosensitive adhesive composition of the present invention, the solution of the copolymer obtained by the polymerization reaction in the (D) solvent can be used as it is, and in this case, the solution of the component (A) Similarly to the above, when adding component (B), component (C), etc. to form a uniform solution, additional solvent (D) may be added for the purpose of concentration adjustment. At this time, the (D) solvent used in the process of forming the specific copolymer and the (D) solvent used for concentration adjustment during the preparation of the positive photosensitive adhesive composition may be the same, or May be different.

The prepared solution of the positive photosensitive adhesive composition is preferably used after being filtered using a filter having a pore size of about 0.2 to 5.0 μm.

<Coating film and cured film>
The positive photosensitive adhesive composition of the present invention can be applied to semiconductor substrates (e.g., silicon/silicon dioxide-coated substrates, silicon nitride substrates, substrates coated with metals such as aluminum, molybdenum, chromium, etc., glass substrates, quartz substrates, ITO substrates). etc.) by spin coating, flow coating, roll coating, slit coating, spin coating following slit coating, inkjet coating, etc., and then pre-drying on a hot plate or oven to form a coating film. can do. Thereafter, a positive photosensitive adhesive film is formed by heat-treating this coating film.

As the conditions for this heat treatment, for example, a heating temperature and heating time appropriately selected from a range of a temperature of 70 to 160° C. and a time of 0.3 to 60 minutes are adopted. The heating temperature and heating time are preferably 80° C. to 140° C. and 0.5 to 10 minutes.

Further, the film thickness of the positive photosensitive adhesive film formed from the positive photosensitive adhesive composition is, for example, 0.1 to 30 μm, further, for example, 1.0 to 10 μm, and further, for example, 2.0 to 8 μm. It is.

A mask with a predetermined pattern is attached to the coating film obtained above, and light such as ultraviolet rays is irradiated, and the exposed area is washed out and the sharp pattern on the edge is created by developing with an alkaline developer. can get.

Examples of alkaline developers that can be used include aqueous solutions of alkali metal hydroxides such as potassium carbonate, sodium carbonate, potassium hydroxide, and sodium hydroxide; hydroxides such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline Examples include alkaline aqueous solutions such as quaternary ammonium aqueous solutions and amine aqueous solutions such as ethanolamine, propylamine, and ethylenediamine. Furthermore, surfactants and the like can also be added to these developers.

Among the above, a 0.1 to 2.38% by mass aqueous solution of tetraethylammonium hydroxide is generally used as a developer for photoresists, and this alkaline developer is also used in the photosensitive adhesive composition of the present invention. , development can be performed satisfactorily without causing problems such as swelling.

Moreover, as a developing method, any of the liquid piling method, dipping method, rocking immersion method, etc. can be used. The developing time at that time is usually 15 to 180 seconds.

After development, the positive photosensitive adhesive film is washed with running water for, for example, 20 to 120 seconds, followed by air drying using compressed air or compressed nitrogen or by spinning to remove moisture on the substrate, and A patterned membrane is obtained.

Subsequently, the pattern-formed film is post-baked for thermosetting, specifically by heating using a hot plate, oven, etc., to improve heat resistance, transparency, and flattening properties. , low water absorption, excellent chemical resistance, etc., and a film with a good pattern can be obtained.

Post-baking is generally performed at a heating temperature selected from the range of 140 to 270°C for 5 to 30 minutes when on a hot plate, and for 30 to 90 minutes when in an oven. method is adopted.

By such post-baking, it is possible to obtain a cured film having a desirable pattern shape.

As described above, the film obtained from the positive photosensitive adhesive composition of the present invention has photosensitivity, flux properties, and adhesive properties, and can be formed by patterning only on necessary locations on the array substrate. , it can be suitably used in applications such as an underfill material that enables efficient mass transfer and metal bonding of LED elements.

EXAMPLES The present invention will be described in more detail with reference to Examples below, but the present invention is not to be construed as being limited thereto. The abbreviations of the compounds used and the measurement methods for each physical property are as follows.
(monomer)
HQMA: p-hydroxyphenyl methacrylate PEA: 2-phenoxyethyl acrylate NOAA: n-octyl acrylate 2EHA: 2-ethyl-n-hexyl acrylate BA: n-butyl acrylate AA: acrylic acid MAA: methacrylic acid MMA: methyl methacrylate HEMA: 2-Hydroxyethyl methacrylate NHPMA: N-(4-hydroxyphenyl)methacrylamide CHMI: N-cyclohexylmaleimide Among the above monomers, HQMA, PEA, and NHPMA correspond to monomer (A1), and NOAA, 2EHA, and BA correspond to monomer (A1). This corresponds to monomer (A2), and AA, MAA, MMA, HEMA, and CHMI correspond to other monomers.
(radical polymerization initiator)
AIBN: α,α'-azobisisobutyronitrile (photosensitizer)
QD: 4,4'-[1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethylidene]bisphenol and 6-diazo-5,6-dihydro-5-oxo-1- Ester with naphthalene sulfonic acid (manufactured by Toyo Gosei Co., Ltd.)
(Crosslinkable compound)
T1: Epolead GT-401 (butanetetracarboxylic acid tetra(3,4-epoxycyclohexylmethyl) modified ε-caprolactone, manufactured by Daicel Corporation)
T2: Epocalic DE-102 (manufactured by ENEOS Co., Ltd.)
T3: TEPIC-FL (manufactured by Nissan Chemical Co., Ltd.)
(solvent)
PGME: Propylene glycol monomethyl ether

<Measurement of molecular weight>
The molecular weight of the polymer was determined using a room temperature gel permeation chromatography (GPC) device (GPC-101) (manufactured by Showa Denko) and a column (KD-803, KD-805 in series) (manufactured by Showa Denko) as follows: It was measured as follows.
Column temperature: 50℃
Eluent: N,N-dimethylformamide (as additives, lithium bromide monohydrate (LiBr.H ₂ O) is 30 mmol/L (liter), phosphoric acid/anhydrous crystal (o-phosphoric acid) is 30 mmol/ L, tetrahydrofuran (THF) 10 mL/L)
Flow rate: 1.0 ml/min Standard sample for creating a calibration curve: TSK standard polyethylene oxide (molecular weight: approx. 900,000, 150,000, 100,000 and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight: approx. 12,000, 4,000 and 1,000) (manufactured by Polymer Laboratory).

<Measurement of glass transition temperature (Tg)>
The Tg of the polymer obtained in the synthesis example was measured using differential scanning calorimetry (DSC) DSC1 (manufactured by METTLER TOREDO) under the following conditions.
Temperature increase rate: 10℃/min
Measurement temperature: -50℃~150℃
Number of measurements: 2 times. Tg is calculated from the second heating result.

<Synthesis of acrylic polymer>
(Synthesis example 1)
HQMA (6.0 g), PEA (6.0 g), and NOAA (8.0 g) were used as monomer components constituting the acrylic polymer, and AIBN (0.2 g) was used as a radical polymerization initiator. By polymerizing these in the solvent PGME (16.8 g) at a temperature of 60°C, an alkali-soluble acrylic polymer component having Mn (number average molecular weight): 8,100 and Mw (weight average molecular weight): 50,000 was obtained. (Specific copolymer) solution P1 (acrylic polymer concentration: 30.0% by mass) was obtained. This specific polymer solution was reprecipitated in water and then dried under vacuum at 50°C to obtain a viscous resin. The Tg of the obtained acrylic polymer was -1°C.

(Synthesis example 2) ~ (Synthesis example 6)
A polymerization reaction was carried out in the same manner as in Synthesis Example 1, except that the ratio (mass ratio) of the monomer components constituting the acrylic polymer used and the radical polymerization initiator was changed as shown in Table 1, and the molecular weight and Solutions P2 to P6 of acrylic polymers of Tg (acrylic polymer concentration: 30.0% by mass) were obtained.

(Synthesis example 7)
NHPMA (4.0 g), HEMA (2.0 g), and CHMI (4.0 g) were used as monomer components constituting the acrylic polymer, and AIBN (0.2 g) was used as a radical polymerization initiator. By polymerizing these in the solvent PGME (46.5 g) at a temperature of 90°C, an alkali-soluble acrylic polymer component having Mn (number average molecular weight): 5,600 and Mw (weight average molecular weight): 9,300 was obtained. (Specific copolymer) solution P7 (acrylic polymer concentration: 18.0% by mass) was obtained. The obtained acrylic polymer did not have a clear Tg up to 150°C.

<Preparation of positive photosensitive adhesive composition>
(Example 1-1)
As a resin solution, a photosensitizer, a crosslinking compound, and a solvent were added to the acrylic polymer solution (P1) obtained in Synthesis Example 1 above, and then stirred at room temperature for 2 hours to obtain a positive type resin solution having the composition shown in Table 2. A photosensitive adhesive composition V1 was prepared.

(Examples 1-2 to 1-5) and (Comparative Examples 1-1 to 1-3)
After changing the types and amounts of the resin solution, photosensitizer, crosslinking compound, and solvent as shown in Table 2 and adding them, the mixture was stirred at room temperature for 2 hours to obtain a positive photosensitive adhesive composition V2 having the composition shown in Table 2. -V5 and RV1-RV3 were prepared.

(Example 2-1)
<Adhesive strength evaluation>
The positive photosensitive adhesive composition V1 prepared in Example 1-1 was applied onto a 5 cm x 5 cm ITO substrate using a spin coater, and then prebaked on a hot plate at a temperature of 100°C for 120 seconds to form a film. A prebaked film with a thickness of 3 μm was formed. After that, using a texture analyzer manufactured by Stable Micro Systems, a probe (diameter: 25 mm, material: polypropylene), compression speed: 1 mm/s, tension speed: 1 mm/s, compression load: 400 g, compression holding time: 10 s The peel strength of the surface of the coating film at room temperature (23° C.) was measured, and 0.3 g or more was evaluated as ○, and less than 0.3 g was evaluated as ×. The results are shown in Table 3.

<Patterning evaluation>
The positive photosensitive adhesive composition V1 prepared in Example 1-1 was applied onto a 5 cm x 5 cm ITO substrate using a spin coater, and then prebaked on a hot plate at a temperature of 100°C for 120 seconds to form a film. A prebaked film with a thickness of 3 μm was formed. This pre-baked film was irradiated with ultraviolet light having a wavelength of 365 nm and a light intensity of 200 mJ/cm ² through a mask to produce a pattern in which lines/spaces were arranged at intervals of 30 μm/30 μm. Thereafter, the film was developed by immersing it in a 2.38% by mass aqueous solution of tetramethylammonium hydroxide (hereinafter referred to as TMAH) for 60 seconds, and then washed with running ultrapure water for 30 seconds. Thereafter, post-baking was performed at 230° C. for 30 minutes using a clean oven manufactured by ADVANTEC to form a cured film. Those whose pattern height of the obtained cured film was less than ±10% of the prebaked film thickness of 3 μm were evaluated as good (◯), and those whose pattern height was ±10% or more were evaluated as poor (x). In addition, as for evaluation of residue in the punched pattern, those with a residue of less than 30 nm were evaluated as excellent (◎), those with a residue of 30 nm or more but less than 60 nm were evaluated as good (○), and those with a residue of 60 nm or more were evaluated as poor (x). The results are shown in Table 3.

(Examples 2-2 to 2-5 and Comparative Examples 2-1 to 2-3)
Using the positive photosensitive adhesive compositions V2 to V5 and RV1 to RV3 prepared in Examples 1-2 to 1-5 and Comparative Examples 1-1 to 1-3, in the same manner as in Example 2-1. Adhesive strength and patterning properties were evaluated. The results are shown in Table 3.

As shown in Table 3, all of the positive photosensitive adhesive compositions of Examples exhibited good adhesive strength and patterning properties. On the other hand, positive photosensitive adhesive compositions using an acrylic polymer having a glass transition temperature (Tg) of 100° C. or higher had insufficient adhesive strength (Comparative Examples 2-1 and 2-3). Furthermore, acrylic polymers in which the acidic component was carboxylic acid had poor alkali resistance, and no pattern shape could be obtained (Comparative Examples 2-1 and 2-2).

(Example 3-1)
<Flip chip bonding test>
As a mounting sample, TEG (Test Element Group) has 1700 electrodes with an electrode area of 20 μm x 20 μm and an electrode height of 5.5 μm (SnAg solder height is 2.3 μm, copper post electrode height is 3.2 μm). A chip (5.1 mm x 5.1 mm x 700 μm thick) and a TEG substrate (15 mm x 15 mm x 700 μm thick) on which copper electrodes were wired to form a daisy chain with the electrodes of the TEG chip were prepared. After applying the positive photosensitive adhesive composition V1 prepared in Example 1-1 onto the TEG substrate using a spin coater, prebaking was performed on a hot plate at a temperature of 100°C for 120 seconds to form a prebaked film with a thickness of 6 μm. was formed. Next, using a flip chip bonder manufactured by Panasonic Corporation, the TEG chip was flip-chip bonded to the TEG substrate having the prebaked film at a stage temperature of 60° C., a head temperature of 370° C. for 60 seconds, and a head pressure of 150 N. Thereafter, post-baking (post-curing) was performed at 230° C. for 30 minutes to obtain a bonded body. The resulting bonded body was evaluated for peeling of the TEG chip (no peeling: ○, peeling: ×) and conduction resistance value (less than 100 Ω: ○, 100 Ω or more: ×). The results are shown in Table 4.

(Examples 3-2 to 3-4, Comparative Example 3-1)
A flip chip bonding test was conducted in the same manner as in Example 3-1 using positive photosensitive adhesive compositions V2 to V4 and RV3 prepared in Examples 1-2 to 1-4 and Comparative Example 1-3. did. The results are shown in Table 4.

(Comparative example 3-2)
Example 3-1 except that instead of using a positive photosensitive adhesive composition, the TEG chip and TEG substrate were cleaned with a 5% by mass sulfuric acid aqueous solution to remove the surface oxide film before flip-chip bonding. A bonded body was similarly formed, and the presence or absence of peeling of the TEG chip was checked and the conduction resistance value was measured. The results are shown in Table 4.

As shown in Table 4, in the TEG bonded bodies using the positive photosensitive adhesive compositions of Examples, the TEG chips did not peel off and the conduction resistance values were also good (Examples 3-1 to 3). -4). On the other hand, in the TEG bonded body using the positive photosensitive adhesive composition of the comparative example, although the TEG chip did not peel off, the conduction resistance value was poor, and the resin composition between the electrodes was insufficient during flip chip bonding. (Comparative Example 3-1). Furthermore, when a positive photosensitive adhesive composition was not used, peeling of the TEG chip increased significantly and resistance value measurement could not be performed with good reproducibility (Comparative Example 3-2).

Claims (11)

A positive photosensitive adhesive composition containing the following (A) component, (B) component, (C) component, and (D) solvent.
(A) Component: Alkali-soluble resin having a phenolic hydroxyl group and having a glass transition temperature (Tg) of the polymer of 60°C or lower (B) Component: Crosslinking agent (C) Component: Photosensitive agent (D) having a quinonediazide ) Ingredients: Solvent The positive photosensitive adhesive composition according to claim 1, wherein the component (A) is a polymer containing a structural unit derived from a monomer (A2) whose homopolymer has a Tg of 0° C. or less. The component (A) contains, as a constituent component, a monomer (A1) having a phenolic hydroxyl group and a polymerizable unsaturated group, and a constituent unit derived from a monomer (A2) whose homopolymer has a Tg of 0°C or less. The positive photosensitive adhesive composition according to claim 2, which is an acrylic polymer. The monomer (A1) having a phenolic hydroxyl group and a polymerizable unsaturated group is selected from p-hydroxystyrene, m-hydroxystyrene, α-methyl-p-hydroxystyrene, and a compound represented by the following formula (1). The positive photosensitive adhesive composition according to claim 3, which is selected from the group consisting of:
In formula (1), P represents a (meth)acrylic group, a (meth)acrylamide group, an N-methyl (meth)acrylamide group, or a maleimide group, and b ₁ is a single bond or a straight chain having 1 to 12 carbon atoms. , branched or cyclic, and a combination thereof, c ₁ represents a single bond, -O-, -COO-, or -OCO-, and d ₁ represents a substituted or unsubstituted hydroxyphenyl group. . The positive-working photosensitive adhesive composition according to any one of claims 3 to 4, wherein the monomer (A2) that makes the homopolymer have a Tg of 0° C. or less is a compound represented by the following formula (2). .
In formula (2), R ₂ represents a hydrogen atom or a methyl group, a ₂ represents an oxygen atom or a sulfur atom, and b ₂ is a linear, branched, or cyclic chain having 2 to 20 carbon atoms, or a combination thereof. It represents an alkylene group, and -CH ₂ - in the alkylene group may be replaced with an oxygen atom, provided that they are not adjacent to each other. c ₂ represents a single bond, -O-, -COO-, or -OCO-, and d ₂ represents a hydrogen atom or a hydroxyl group. Claims 1 to 5, wherein the component (A) is an acrylic polymer further containing as a constituent a constituent unit derived from a monomer (A3) containing an aromatic hydrocarbon group represented by the following formula (3). The positive photosensitive adhesive composition according to any one of the above.
In formula (3), R ₃ represents a hydrogen atom or a methyl group, a ₃ represents an oxygen atom, a sulfur atom, -NH-, or -N(CH ₃ )-, and b ₃ represents a single bond or the number of carbon atoms Represents an alkylene group consisting of 1 to 20 linear, branched, or cyclic, or a combination thereof, and -CH ₂ - in the alkylene group may be replaced with an oxygen atom, provided that they are not adjacent to each other. . c ₃ represents a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -N(CH ₃ )CO-, or -CON(CH ₃ )-, and d ₃ represents carbon Represents 6 to 10 substituted or unsubstituted aromatic hydrocarbon groups. The positive photosensitive adhesive composition according to any one of claims 1 to 6, wherein the component (B) is present in an amount of 5 to 60 parts by mass relative to 100 parts by mass of the component (A). The positive photosensitive adhesive composition according to any one of claims 1 to 7, wherein the component (C) is present in an amount of 10 to 100 parts by mass relative to 100 parts by mass of the component (A). The positive photosensitive material according to any one of claims 1 to 8, further comprising 0.01 to 1.0 parts by mass of a surfactant as component (E) based on 100 parts by mass of component (A). adhesive composition. A cured film obtained by curing the positive photosensitive adhesive composition according to any one of claims 1 to 9. An LED display element comprising the cured film according to claim 10 as an underfill material.