JP2019113690A - Photosensitive adhesive composition and structure - Google Patents

Abstract

To provide a photosensitive adhesive composition excellent in adhesion to a substrate.SOLUTION: The photosensitive adhesive composition of the present invention to be used for forming an organic insulating layer which is interposed between a first circuit board and a second circuit board to bond them together contains: a copolymer having a structural unit A derived from a norbornene-based monomer and a structural unit B derived from maleic anhydride, maleimide, or a derivative thereof; a photosensitive agent; and a crosslinking agent.SELECTED DRAWING: Figure 1

Description

  The present invention relates to photosensitive adhesive compositions and structures.

  Various developments have been made in the past for bonding electronic components. As this type of technology, for example, the technology described in Patent Document 1 is known. Patent Document 1 describes a chemically amplified negative resist composition material containing a silicone skeleton-containing polymer compound, a photoacid generator, and an epoxy group-containing crosslinking agent (Table 1 of Patent Document 1).

JP, 2017-152602, A

  However, as a result of the present inventor's investigation, it turned out that the negative resist composition material described in Patent Document 1 has room for improvement in terms of substrate adhesion.

  As a result of further investigations by the inventor of the present invention, the use of a copolymer containing a structural unit derived from a norbornene-based monomer in a photosensitive adhesive composition makes it possible to use a substrate such as a first circuit substrate or a second circuit substrate. It has been found that adhesion, that is, substrate adhesion, is improved, and the present invention has been completed.

According to the invention
A photosensitive adhesive composition, which is used to form an organic insulating layer for bonding a first circuit board and a second circuit board between them,
A copolymer having a structural unit A derived from a norbornene-based monomer and a structural unit B derived from maleic anhydride, maleimide or their derivatives;
A photosensitizer,
A photosensitive adhesive composition is provided, which comprises: a crosslinking agent.

  Further, according to the present invention, there is provided a structure comprising the cured product of the photosensitive adhesive composition.

  According to the present invention, a photosensitive adhesive composition excellent in substrate adhesion and a structure using the cured product thereof are provided.

It is a sectional view showing typically the composition of the electronic device concerning this embodiment. It is process sectional drawing which shows the outline | summary of the manufacturing process of the electronic device which concerns on this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description thereof will be appropriately omitted. Also, the figure is a schematic view and does not match the actual dimensional ratio.

The outline of the photosensitive adhesive composition of the present embodiment will be described.
The photosensitive adhesive composition of the present embodiment comprises a copolymer having a structural unit A derived from a norbornene-based monomer and a structural unit B derived from maleic anhydride, maleimide or a derivative thereof, a photosensitizer, and a crosslinking agent. And can be included.

  According to the photosensitive adhesive composition of the present embodiment, it is possible to improve the adhesion of the substrate to the circuit board constituting the electronic component. Thereby, the structure of the electronic device excellent in reliability and manufacturing stability can be realized.

  The photosensitive adhesive composition of the present embodiment can be used to form an organic insulating layer for interposing and bonding the first circuit board and the second circuit board therebetween. The first circuit board may be a first semiconductor chip or a first semiconductor wafer, and the second circuit board may be a second semiconductor chip or a second semiconductor wafer. Therefore, the photosensitive adhesive composition of the present embodiment can be adapted to a lamination process (bonding step) of a circuit board such as a chip on wafer (COW), a chip on chip (COC), a wafer on wafer (WOW) or the like.

  The resin film made of the photosensitive adhesive composition functions as an adhesive layer, and can be disposed on at least one of the first circuit board and the second circuit board, preferably both of them. After that, the first circuit board and the second circuit board are bonded with the resin film interposed therebetween, and the resin film is post-cured to realize an organic insulating layer in close contact with these. The resin film has adhesiveness even after exposure and development processing, and the adhesiveness can be enhanced by post curing.

The resin film made of the photosensitive adhesive composition is excellent in adhesion to the circuit substrate, but may be excellent in adhesion between the resin films, that is, adhesion between the films. Hereinafter, the process of bonding the films in the bonding step is referred to as “film bonding”.
Although the detailed mechanism is not clear, the resin film contains a structural unit derived from a norbornene monomer in the copolymer, and after curing after exposure and development, the crosslinking agent and the functional group in the copolymer It is considered that the adhesion of the substrate to the circuit board and the adhesion of the films to each other can be enhanced by performing the crosslinking reaction or appropriately selecting the kind of the functional group to cause the crosslinking reaction of the functional groups.

  As said resin film, the 1st resin film arrange | positioned at the 1st circuit board, and the 2nd resin film arrange | positioned at the 2nd board | substrate are mentioned. It is preferable that at least one of the first resin film and the second resin film is in the B-stage state when the resin films of the first resin film and the second resin film are attached to each other (film bonding). Resin films in the B-stage state (semi-hardened state) can be bonded under low temperature conditions. As the low temperature condition, for example, a bonding temperature of about 170 ° C. can be employed. This can improve process suitability. In addition, resin films in the B-stage state (semi-cured state) and the C-stage state (cured state) can be bonded under high temperature conditions higher than the above-described low temperature conditions. As the high temperature condition, a bonding temperature of about 260 ° C. can be adopted.

  Moreover, the photosensitive adhesive composition of this embodiment can be used in order to form the organic insulating layer which embeds the metal joint part which electrically connects a 1st circuit board and a 2nd circuit board. Since the copolymer in the photosensitive adhesive composition has a norbornene skeleton, an organic insulating layer with a low dielectric constant can be realized. As a result, since crosstalk can be suppressed in adjacent metal junctions in the fine wiring structure, an electronic device excellent in connection reliability can be realized.

  The dielectric constant of the cured film of the photosensitive adhesive composition cured under conditions of 200 ° C. for 90 minutes in a nitrogen atmosphere, measured by the cylindrical cavity resonator method, at 25 ° C. and a frequency of 1 GHz is, for example, 3.3. It is 3 or less, preferably 3.2 or less, and more preferably 3.1 or less.

  Further, the metal bonding portion can be made of copper from the viewpoint of signal speed. This metal joint may be comprised of copper plated or copper pillars. At this time, the copolymer in the photosensitive adhesive composition preferably has a carbonyl group. Although the detailed mechanism is not clear, it is considered that the carbonyl group in the copolymer coordinates with copper in the metal junction to improve the adhesion between the organic insulating layer and the metal junction. The carbonyl group may be derived from the above-mentioned functional group in the copolymer, or may be derived from an ester compound in which the acid anhydride ring of maleic anhydride is ring-opened.

  In addition, at the time of film bonding, it is possible to set one of the first resin film and the second resin film in a cured state. Thereby, it is possible to form a metal joint by plating.

  The resin film made of the photosensitive adhesive composition of the present embodiment can achieve adhesion not only in a thick film but also in a thin film. At this time, the thickness of the organic insulating layer (cured film of resin film) between the first circuit board and the second circuit board is, for example, 10 μm or less and can be 8 μm or less. Further, the resin film at the time of thin film used for film bonding may be, for example, 5 μm or less, 3 μm or less, or 1 μm or less. The lower limit value of each thickness is not particularly limited, but may be, for example, 0.1 μm or more.

  Hereinafter, each component of the photosensitive adhesive composition of this embodiment is explained in full detail.

  The photosensitive adhesive composition of this embodiment contains a copolymer having a structural unit A derived from a norbornene-based monomer and a structural unit B derived from maleic anhydride, maleimide or a derivative thereof. Since the copolymer has the structural unit A, adhesion can be improved, and low dielectricity can be realized in the organic insulating layer (cured film). Moreover, since the copolymer has the structural unit B, processability can be improved.

The above-mentioned copolymer can have a functional group which carries out a crosslinking reaction with a crosslinking agent.
When the crosslinking agent has a cyclic ether group, the functional group is one having a functional group that crosslinks with the cyclic ether group in the crosslinking agent. Adhesion and mechanical properties can be improved by such a crosslinked structure of the copolymer and the crosslinking agent.

  The functional group in the above-mentioned copolymer should just have at least one of the structural unit A and the structural unit B, and may have any.

  The structural unit A derived from the norbornene-based monomer can include a structural unit represented by the following formula (2). The structural unit A may be used alone or in combination of two or more. Since the structural unit A has a norbornene skeleton derived from a norbornene-based monomer, it is possible to reduce the dielectric constant and to realize low dielectric property in the cured product of the photosensitive adhesive composition.

In the formula _{(2), R 1, R} 2, R 3 and _{R 4} are each independently a hydrogen atom, a hydroxyl group or an organic group having 1 to 30 carbon atoms, preferably an organic group having 1 to 10 carbon atoms It is. These organic groups may have functional groups such as carboxyl group, glycidyl group and oxetanyl group.
In the formula (2), n is, for example, 0, 1 or 2, preferably 0 or 1, and more preferably 0.
In the present specification, “to” means including the upper limit value and the lower limit value unless otherwise specified.

The organic group constituting R _{1 to} R ₄ may contain one or more atoms selected from O, N, S, P and Si in its structure.

In this embodiment, examples of the organic group constituting R _{1 to} R ₄ include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group, an alkaryl group, a cycloalkyl group, and a heterocyclic group. Be
Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, Examples include octyl group, nonyl group, and decyl group. As an alkenyl group, an allyl group, pentenyl group, and a vinyl group are mentioned, for example. The alkynyl group includes an ethynyl group. The alkylidene group includes, for example, a methylidene group and an ethylidene group. Examples of the aryl group include tolyl group, xylyl group, phenyl group, naphthyl group and anthracenyl group. As an aralkyl group, a benzyl group and a phenethyl group are mentioned, for example. Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. The heterocyclic group includes, for example, an epoxy group and an oxetanyl group.

Furthermore, in the alkyl group, the alkenyl group, the alkynyl group, the alkylidene group, the aryl group, the aralkyl group, the alkaryl group, the cycloalkyl group and the heterocyclic group constituting R _{1 to} R _4, at least one hydrogen atom is a halogen atom It may be substituted by The halogen atom includes fluorine, chlorine, bromine and iodine. Among them, a haloalkyl group in which at least one hydrogen atom of the alkyl group is substituted with a halogen atom is preferable. When at least one of R _{1 to} R ₄ is a haloalkyl group, when a cured film is formed using a copolymer, the dielectric constant of the cured film can be reduced. In addition, by using a haloalkyl alcohol group, it is possible not only to appropriately adjust the solubility in an alkaline developer but also to improve the heat discoloration resistance.
In addition, it is preferable that one of R _{1 to} R ₄ is hydrogen from the viewpoint of enhancing the light transmittance of a film configured to contain a polymer, and, for example, when adopting the structural unit of the formula (2) Preferably, all of R _{1 to} R ₄ are hydrogen.

  As a monomer having a norbornene skeleton, specifically, for example, 2-norbornene; 5-methyl-2-norbornene, 5, 5-dimethyl-2-norbornene, 5-ethyl-2-norbornene, 5-butyl-2- Norbornenes having an alkyl group (C1-C10 alkyl group) such as norbornene; norbornenes having an alkenyl group such as 5-ethylidene-2-norbornene; 5-methoxycarbonyl-2-norbornene, 5-methyl-5-methoxycarbonyl Norbornenes having an alkoxycarbonyl group such as 2-norbornene; norbornenes having a cyano group such as 5-cyano-2-norbornene; 5-phenyl-2-norbornene, 5-phenyl-5-methyl-2-norbornene and the like Norbornenes Having an Aryl Group of -Octalin; 6-ethyl - such -octalin having an alkyl group such as octahydronaphthalene can be exemplified.

  These norbornene monomers can be used alone or in combination of two or more. Among these bicyclic olefins, norbornenes such as norbornene and norbornene having an alkyl group (a C1 to C10 alkyl group such as a methyl group or an ethyl group) are preferable.

  The structural unit B derived from the above-mentioned maleic anhydride, maleimide or a derivative thereof can include a structural unit derived from maleic anhydride or a maleic anhydride derivative (maleic anhydride based monomer).

  Examples of the above-mentioned maleic anhydride or maleic anhydride derivative include maleic anhydride, citraconic anhydride, dimethyl maleic anhydride or derivatives thereof. These may be used alone or in combination of two or more. Thus, the copolymer can comprise structural units derived from unsaturated carboxylic acid anhydrides having a cyclic structure in the molecule.

  The structural unit derived from the above-mentioned maleic anhydride or maleic anhydride derivative can include a structural unit represented by the following formula (1).

In the above formula (1), R _X and R _Y each independently are preferably hydrogen or an organic group having 1 to 3 carbon atoms, and each independently may be hydrogen or an organic group having 1 carbon atom It is more preferable that R _X be hydrogen and R _Y be hydrogen or an organic group having 1 carbon atom, and it is more preferable that R _X and R _Y be hydrogen.

In the present embodiment, examples of the organic group constituting R _X and R _Y in the above-mentioned formula (1) include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, a cycloalkyl group and a heterocyclic group. Moreover, as an alkyl group, a methyl group, an ethyl group, n-propyl group is mentioned, for example. As an alkenyl group, an allyl group and a vinyl group are mentioned, for example. The alkynyl group includes an ethynyl group. The alkylidene group includes, for example, a methylidene group and an ethylidene group. As a cycloalkyl group, a cyclopropyl group is mentioned, for example. The heterocyclic group includes, for example, an epoxy group and an oxetanyl group.

  The copolymer may have a structural unit derived from an ester compound in which an acid anhydride in a structural unit A represented by the following formula (1) is ring-opened, and preferably, the acid anhydride ring of maleic anhydride is It can have a structural unit C derived from a ring-opened ester compound.

  The structural unit C can include, for example, a structural unit represented by the following formula (B2). These may be used alone or in combination of two or more.

R ^B1 in the general formula (B2) contains hydrogen or an organic group having 1 to 30 carbon atoms. This R ^B1 may be an organic group linked via a linking group by an ester bond, an amide bond, a ketone bond, a urea bond, a urethane bond or the like.

As an organic group which comprises R ^B1 in said general formula (B2), an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group, an alkaryl group, a cycloalkyl group, an alkoxy group, and a heterocyclic ring are mentioned, for example Groups are mentioned.

Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group And octyl, nonyl and decyl groups. As an alkenyl group, an allyl group, pentenyl group, and a vinyl group are mentioned, for example. The alkynyl group includes an ethynyl group. The alkylidene group includes, for example, a methylidene group and an ethylidene group. Examples of the aryl group include tolyl group, xylyl group, phenyl group, naphthyl group and anthracenyl group. As an aralkyl group, a benzyl group and a phenethyl group are mentioned, for example. Examples of the alkaryl group include tolyl group and xylyl group. Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. As an alkoxy group, for example, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, s-butoxy group, isobutoxy group and t-butoxy group, n-pentyloxy group, neopentyloxy group And n-hexyloxy group. The heterocyclic group includes, for example, an epoxy group and an oxetanyl group.
As R ^B1 in the above general formula (B2), for example, one or more selected from the group consisting of an alkyl group, an alkenyl group and an alkynyl group is preferable, and an alkyl group or an alkenyl group is preferred. preferable. Thus, it is possible to suppress the bond in R ^B1 is cleaved. Therefore, the heat resistance of the copolymer can be improved.

In the above general formula (B2), R ^B1 is, for example, an aliphatic group formed by one or more atoms selected from the group consisting of a hydrogen atom and a carbon atom, which is bonded via an ester bond Is preferred, and a hydrocarbon group is more preferred.

  The structural unit B derived from the above-mentioned maleic anhydride, maleimide or a derivative thereof can contain a structural unit derived from a maleimide or a maleimide derivative. Thereby, processability and heat resistance can be improved.

  The structural unit derived from the maleimide or maleimide derivative can include a structural unit derived from a maleimide-based monomer represented by the following formula (8). These may be used alone or in combination of two or more.

R ₁₂ is an organic group of a hydrogen atom or a C1-C30. The organic group of C1~C30 constituting the R _12, for example, an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group, and a hydrocarbon group, an alkaryl group or cycloalkyl group. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, Examples include octyl group, nonyl group, and decyl group. As an alkenyl group, an allyl group, pentenyl group, and a vinyl group are mentioned, for example. The alkynyl group includes an ethynyl group. The alkylidene group includes, for example, a methylidene group and an ethylidene group. As an aryl group, a phenyl group and a naphthyl group are mentioned, for example. As an aralkyl group, a benzyl group and a phenethyl group are mentioned, for example. Examples of the alkaryl group include tolyl group and xylyl group. Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. In addition, one or more hydrogen atoms contained in R ₅ may be substituted by a halogen atom such as fluorine, chlorine, bromine or iodine.

In addition to the above-mentioned structural unit A to structural unit C, the above-mentioned copolymer may contain structural unit D derived from a compound having another ethylenic double bond. Examples of other compounds having an ethylenic double bond include styrene, styrenes such as hydroxystyrene, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3- Methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc. Α-olefins of 1, 4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 1,7-octadiene, etc. Conjugated dienes; acrylic acids such as acrylic acid, methacrylic acid, α-ethyl acrylic acid and 2-hydroxyethyl (meth) acrylic acid; and maleic acids such as maleic acid, dimethylmaleic acid, diethylmaleic acid and dibutylmaleic acid Be These monomers can be used alone or in combination of two or more.

  In the photosensitive adhesive composition of the present embodiment, the content of the copolymer is 20% by mass or more and 80% by mass or less with respect to 100% by mass of the nonvolatile components of the photosensitive adhesive composition. Preferably it is 30 to 70 mass%, More preferably, it is 40 to 60 mass%. By setting it as such a numerical range, it is possible to aim at balance with adhesiveness and processability.

  In the present embodiment, the non-volatile component of the photosensitive adhesive composition refers to the remainder excluding volatile components such as water and solvent. The content of the photosensitive adhesive composition with respect to the whole of the non-volatile components refers to the content of the photosensitive adhesive composition with respect to the whole of the non-volatile components excluding the solvent when it contains a solvent.

  The photosensitive adhesive composition of the present embodiment can contain a crosslinking agent. The crosslinking agent is not particularly limited as long as it can crosslink with the above-mentioned copolymer. Adhesion can be improved by this.

The crosslinking agent can include a compound having a cyclic ether group.
By including a compound having a cyclic ether group, adhesion in post curing after exposure and development can be improved. Although the detailed mechanism is not clear, the curing reaction of the resin film made of the photosensitive adhesive composition can be suppressed before the bonding step of the first circuit board and the second circuit board, so the curing reaction is sufficient in post curing It is thought that it is possible to proceed and achieve high adhesion at the time of post curing.

  The compound having a cyclic ether group can include, for example, an epoxy resin or an oxetane compound.

  As the epoxy resin, for example, an epoxy resin having two or more epoxy groups in one molecule can be used. As the epoxy resin, monomers, oligomers and polymers in general can be used, and their molecular weight and molecular structure are not particularly limited. Examples of the epoxy resin include phenol novolac epoxy resin, cresol novolac epoxy resin, cresol naphthol epoxy resin, biphenyl epoxy resin, biphenyl aralkyl epoxy resin, phenoxy resin, naphthalene skeleton epoxy resin, bisphenol A epoxy resin , Bisphenol A diglycidyl ether type epoxy resin, bisphenol F type epoxy resin, bisphenol F diglycidyl ether type epoxy resin, bisphenol S diglycidyl ether type epoxy resin, glycidyl ether type epoxy resin, cresol novolac type epoxy resin, aromatic polyfunctional Epoxy resin, aliphatic epoxy resin, aliphatic polyfunctional epoxy resin, alicyclic epoxy resin, polyfunctional alicyclic epoxy resin, etc. That. The epoxy resins may be used alone or in combination of two or more.

The epoxy resin may contain a trifunctional or higher polyfunctional epoxy resin (that is, one having three or more epoxy groups in one molecule). As a polyfunctional epoxy resin, what is trifunctional and 20 or less functional is more preferable.
As a polyfunctional epoxy resin, for example, 2- [4- (2,3-epoxypropoxy) phenyl] -2- [4- [1,1-bis [4-([2,3-epoxypropoxy] phenyl)] Ethyl] phenyl] propane, phenol novolac epoxy, tetrakis (glycidyloxyphenyl) ethane, α-2,3-epoxypropoxyphenyl-ω-hydropoly (n = 1 to 7) {2- (2,3-epoxypropoxy) Benzylidene-2,3-epoxypropoxyphenylene}, 1-chloro-2,3-epoxypropane-formaldehyde- 2,7-naphthalenediol polycondensate, dicyclopentadiene type epoxy resin, etc. are used. These may be used alone or in combination of two or more.

The oxetane compound is not particularly limited as long as it is a compound having an oxetanyl group, and, for example, for example, 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, bis [1-ethyl (3-oxetanyl) )] Methyl ether, 4,4′-bis [(3-ethyl-3-oxetanyl) methoxymethyl] biphenyl, 4,4′-bis (3-ethyl-3-oxetanylmethoxy) biphenyl, ethylene glycol bis (3- (3-ethyl-3-oxetanyl) biphenyl) Ethyl-3-oxetanylmethyl) ether, diethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, bis (3-ethyl-3-oxetanylmethyl) diphenoate, trimethylolpropane tris (3-ethyl-3-oxetanylmethyl) Ether, pentaerythritol tetra Thi (3-ethyl-3-oxetanylmethyl) ether, poly [[3-[(3-ethyl-3-oxetanyl) methoxy] propyl] silasesquioxane] derivative, oxetanyl silicate, phenol novolac type oxetane, 1,3- Examples include bis [(3-ethyloxetan-3-yl) methoxy] benzene and the like. These may be used alone or in combination of two or more.

  The lower limit of the content of the crosslinking agent is, for example, 10% by mass or more, preferably 15% by mass or more, and more preferably 20% by mass or more, based on the total of the non-volatile components of the photosensitive adhesive composition. It is. Thereby, in the hardened | cured material of a photosensitive adhesive composition, heat resistance and mechanical strength can be improved. On the other hand, the upper limit value of the content of the crosslinking agent is, for example, 50% by mass or less, preferably 45% by mass or less, and more preferably 40% by mass, based on the total nonvolatile components of the photosensitive adhesive composition. It is below. Thereby, in the photosensitive adhesive composition, the patterning property can be improved.

  The photosensitive adhesive composition of the present embodiment can contain a phenol resin as a curing agent. As this phenolic resin, monomers, oligomers, and polymers in general can be used, and the molecular weight and molecular structure thereof are not particularly limited. By including a phenol resin, compatibility and processability can be improved. Although the detailed mechanism is not clear, it is considered that the compatibility between the copolymer and the photosensitive agent can be enhanced in the varnish-like photosensitive adhesive composition. When a diazoquinone compound is used as a photosensitizer, it can be azo-coupled with the compound, thereby reducing film loss during development and improving resolution.

  It is preferable that the said phenol resin contains the polyfunctional phenol resin which has a 2 or more phenolic hydroxyl group in a molecule | numerator.

  The following phenol resins and low molecular weight phenol compounds can be used as the above-mentioned phenol resin. As this phenol resin, although it can select suitably from well-known things, a novolak-type phenol resin, a resol-type phenol resin, a trisphenyl methane-type phenol resin, an aryl alkylene type phenol resin can be used, for example. From the viewpoint of good development characteristics, novolac phenolic resins can be used. As low molecular weight phenolic compounds, biphenol, 4-ethylresorcinol, 2-propylresorcinol, 4-butylresorcinol, 4-hexylresorcinol, 4-hexylresorcinol, 2-hydroxybenzoic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid Acid, 4,4'-dihydroxydiphenyl sulfide, 3,3'-dihydroxydiphenyl disulfide, 4,4'-dihydroxydiphenyl sulfone, 2,2'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenylmethane, 2,2'- Dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ether, biphenol, 4,4 '-(1,3-dimethylbutylidene) diphenol, 4,4'-(2-ethylhexylidene) diphenol, 4,4 ' -Ethylenbi Phenol, 2,2'-ethylenedioxydiphenol, 3,3'-ethylenedioxydiphenol, 1,5-bis (o-hydroxyphenoxy) -3-oxapentane, bisphenol A, bisphenol F, phloroglucide, alpha And α, α'-tris (4-hydroxyphenyl) -1-ethyl-4-isopropylbenzene and the like. These may be used alone or in combination of two or more.

  The content of the above-mentioned phenol resin is, for example, 1 part by mass or more and 30 parts by mass or less, preferably 3 parts by mass or more, based on 100 parts by mass of the total content of the copolymer in the photosensitive adhesive composition. It is 20 parts by mass or less, more preferably 5 parts by mass or more and 15 parts by mass or less. By blending within the above range, the heat resistance and the strength of the cured product are improved.

  The photosensitive adhesive composition of the present embodiment can contain the following photosensitive agent as a positive photosensitive adhesive composition. Thereby, processability can be improved. As the photosensitizer, those having light or thermal decomposition can be used. Thus, the photosensitive agent remaining in the resin film after exposure and development can be removed (decomposed) by predetermined exposure processing and heat treatment on the resin film made of the positive photosensitive adhesive composition. Thereby, the adhesion (especially, adhesion between the films) can be enhanced.

  Examples of the photosensitizer include onium salts such as diazoquinone compounds, diaryliodonium salts, triarylsulfonium salts or sulfonium borate salts, 2-nitrobenzyl ester compounds, N-iminosulfonate compounds, imidosulfonate compounds, 2,6-bis ( Trichloromethyl) -1,3,5-triazine compounds or dihydropyridine compounds can be used. Among these, it is particularly preferable to use a diazoquinone compound which is excellent in sensitivity and solvent solubility.

  The content of the photosensitizer in the photosensitive adhesive composition of the present embodiment is not particularly limited, but is preferably 5 parts by mass or more, and 8 parts by mass with respect to 100 parts by mass of the copolymer. It is more preferable that it is part or more. In addition, the content of the photosensitizer in the photosensitive adhesive composition is preferably 50 parts by mass or less, and more preferably 40 parts by mass or less, with respect to 100 parts by mass of the copolymer. Favorable patterning performance can be exhibited when content of a photosensitive agent is in the said range.

The photosensitive adhesive composition of the present embodiment can contain a surfactant. By including the surfactant, a uniform resin film can be obtained, and thin film coatability can be enhanced. In addition, it can be expected to prevent residue and pattern floating during development.
Examples of the surfactant include fluorine-based surfactants, silicon-based surfactants, alkyl-based surfactants, and acrylic-based surfactants.

  The surfactant preferably includes a surfactant containing at least one of a fluorine atom and a silicon atom. In addition to the ability to obtain a uniform resin film (improvement of coatability) and the improvement of developability, this also contributes to the improvement of adhesive strength.

  More specifically, the surfactant is preferably a nonionic surfactant containing at least one of a fluorine atom and a silicon atom. As a commercial item which can be used as surfactant, for example, F-251, F-253, F-281, F-430, F-477, F-551, and the “Megafuck” series manufactured by DIC Corporation. F-552, F-553, F-554, F-555, F-556, F-557, F-558, F-559, F-560, F-561, F-562, F-563, F- 565, F-568, F-569, F-570, F-572, F-574, F-575, F-576, R-40, R-40-LM, R-41, R-94, etc. Fluorine-containing surfactants having oligomer structure, Ftergent 250 manufactured by Neos Co., Ltd., fluorine-containing nonionic surfactants such as Ftergent 251, etc., SILFOAM (registered trademark) series manufactured by Wacker Chemie (eg SD 100 TS, SD 670, SD 850, SD 860, SD 882), and other silicone surfactants.

  Although the reason why adhesion strength can be improved by a nonionic surfactant containing at least one of a fluorine atom and a silicon atom is not clear, it is presumed that, for example, (i) the film surface becomes smooth, The adhesion area at the time of bonding by heating and pressing the cured film is increased, and (ii) the surfactant is unevenly distributed on the surface of the resin film (cured film), whereby the surface of the cured film is partially melted by heat It is conceivable that it will be easier.

  The content of the surfactant is usually 0.001 to 1% by mass, preferably 0.003 to 0.5% by mass, more preferably 0. 1% by mass, based on the total amount of the non-volatile components of the photosensitive adhesive composition. The content is preferably from 0.55 to 0.3% by mass, more preferably from 0.008 to 0.1% by mass, particularly preferably from 0.01 to 0.05% by mass. By setting it as this range, it can be expected that the effect of the improvement of the above-mentioned adhesive strength will be acquired further.

The photosensitive adhesive composition of the present embodiment can contain a cohesion aid.
Thereby, the adhesion to the substrate can be further improved. Although the detailed mechanism is unknown, the adhesion group (functional group that exerts adhesion ability) of the adhesion assistant is relatively stable to heating, and a certain amount of adhesion after curing at 180 to 250 ° C. As a result of the auxiliary agent remaining in the cured film, it is considered that the remaining adhesion auxiliary agent contributes to the improvement of the adhesive strength.

  Examples of the adhesion assistant include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacrylic acid Roxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl) ) 3-Aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane Silane 3-Aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxypropyl) tetrasulfide, 3-isocyanatepropyltritriol Ethoxysilane, 3-trimethoxysilylpropylsuccinic anhydride, bis (3- (triethoxysilyl) propyl) disulfide, bis (3- (triethoxysilyl) propyl) tetrasulfide, silicon compounds having an amino group and acid Examples thereof include, but are not limited to, silicon compounds and the like obtained by reacting with an anhydride or an acid anhydride.

  The content of the adhesion promoter is generally 0.01 to 20% by mass, preferably 0.1 to 10% by mass, based on the total amount of the non-volatile components of the photosensitive adhesive composition. By setting it as this range, it can be expected that the effect of the improvement of the above-mentioned adhesive strength will be acquired further.

The photosensitive adhesive composition of the present embodiment can contain a solvent.
Any solvent can be used without particular limitation as long as it can dissolve the components of the photosensitive adhesive composition and does not react chemically with the components. Examples of such organic solvents include, for example, acetone, methyl ethyl ketone, toluene, propylene glycol methyl ethyl ether, propylene glycol dimethyl ether, propylene glycol 1-monomethyl ether 2-acetate, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol mono ether Butyl ether acetate, benzyl alcohol, propylene carbonate, ethylene glycol diacetate, propylene glycol diacetate, propylene glycol monomethyl ether acetate, γ-butyrolactone, butyl acetate, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol Dimethyl ether , Diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, methyl lactate, ethyl lactate, butyl lactate, methyl 1,3-butylene glycol acetate, 1,3-butylene glycol-3-monomethyl ether And organic solvents such as methyl pyruvate, ethyl pyruvate and methyl 3-methoxy propionate. The organic solvent may be used alone or in combination of two or more.

  The organic solvent is preferably used so that the concentration of the total non-volatile component in the photosensitive adhesive composition is 1 to 50% by mass, preferably 5 to 40% by mass. By setting this range, each component can be sufficiently dissolved, and good thin film coatability can be ensured.

  The photosensitive adhesive composition of the present embodiment can contain other additives, as needed, in addition to the components described above. Examples of other additives include antioxidants, fillers such as silica, sensitizers, film-forming agents, adhesion assistants, and the like.

  The method for preparing the photosensitive adhesive resin composition is not particularly limited, and the photosensitive adhesive resin composition can be produced by a generally known method.

  The structure of the present embodiment comprises the cured film of the photosensitive adhesive composition, but can be applied to, for example, an electronic device. FIG. 1 is a cross-sectional view schematically showing a connection structure in the electronic device 100. As shown in FIG.

The electronic device 100 according to the present embodiment includes a first circuit board 102, a second circuit board 104, a metal joint 130 for electrically connecting the first circuit board 102 and the second circuit board 104, and a metal joint. While embedding 130, the 1st circuit board 102 and the 2nd circuit board 104 can be interposed, and the organic insulating layer 110 which adhere | attaches between these can be provided. The organic insulating layer 110 is composed of a cured product of the above-described photosensitive adhesive composition. The organic insulating layer 110 is obtained by curing a single layer of a resin film made of a photosensitive adhesive composition or two layers obtained by bonding the resin films.
The resin film made of the photosensitive adhesive composition of the present embodiment is excellent in the adhesion between the films as well as the adhesion between the substrate, and therefore, the connection reliability and the production stability of the electronic device 100 can be enhanced.

Further, in the electronic device 100, the first circuit board 102 and the second circuit board 104 are electrically connected by a known connection means via the metal bonding portion 130 and the metal layer 132. The metal bonding portion 130 and the metal layer 132 may be directly bonded, but may be bonded via a low-temperature meltable metal or metal alloy such as solder. The metal bonding portion 130 is embedded in the organic insulating layer 110. That is, the periphery of the side surface of the metal bonding portion 130 may be covered with the organic insulating layer 110, and the gap between the adjacent metal bonding portions 130 may be buried with the organic insulating layer 110.
The photosensitive adhesive composition of the present embodiment is excellent in sensitivity and pattern resolution after curing, and since the dielectric constant of the cured film can be relatively low, the first circuit board 102 and the second circuit board 104 The connection reliability of the electronic device 100 provided with the organic insulating layer 110 that embeds the metal junction 130 that electrically connects the electrodes can be enhanced.

<Structure>
The method of obtaining the structure (electronic device) provided with the cured film of the photosensitive adhesive composition of this embodiment is not particularly limited.
For example, the following steps:
Providing a photosensitive adhesive composition on the circuit board (step 1),
A step (step 2) of heating and drying the photosensitive adhesive composition to obtain a photosensitive resin film,
Exposing the photosensitive resin film to actinic radiation (step 3);
Developing the exposed photosensitive resin film to obtain a patterned resin film (step 4);
Process of laminating the first circuit board and the second circuit board through the patterned resin film (step 5)
Heating the resin film to obtain a cured film (step 6);
Thus, a structure (electronic device) including the cured film (organic insulating layer) of the photosensitive adhesive composition of the present embodiment can be obtained.
If necessary, known processes such as dicing can be adopted.

  In the step 1, the substrate is not particularly limited, and examples thereof include a silicon wafer, a ceramic substrate, an aluminum substrate, a SiC wafer, a GaN wafer and the like. The substrate includes, in addition to the unprocessed substrate, for example, a substrate on which a semiconductor element or a display element is formed. Moreover, a printed wiring board etc. may be sufficient. The substrate surface may be treated with an adhesion promoter such as a silane coupling agent in order to improve adhesion. The photosensitive adhesive composition can be provided on a substrate by spin coating, spray coating, immersion, printing, roll coating, an inkjet method, or the like. Among these, spin coating is preferable from the viewpoint of achieving a thin coating film.

  In the step 2, the temperature of the heating and drying is usually 80 to 140 ° C, preferably 90 to 120 ° C. The heating and drying time is usually 30 to 600 seconds, preferably about 30 to 300 seconds. A photosensitive resin film is formed by removing the solvent by this heating and drying. Heating is typically performed with a hot plate, an oven or the like. The thickness of the photosensitive resin film is preferably, for example, about 1 to 500 μm.

In the step 3, for example, X-rays, electron beams, ultraviolet rays, visible light and the like can be used as actinic rays for exposure. In terms of wavelength, actinic radiation of 200 to 500 nm is preferred. The light source is preferably a mercury lamp g-line, h-line or i-line in view of pattern resolution and handleability. Also, two or more light beams may be mixed and used. As the exposure apparatus, a contact aligner, a mirror projection or a stepper is preferable.
After exposure, the photosensitive resin film may be heated again (heating after exposure). The temperature and time of post-exposure heating are, for example, about 80 to 200 ° C. and about 10 to 300 seconds.

  In step 4, development can be performed using a suitable developer, for example, using a method such as immersion, paddle, rotary spray, and the like. Thereby, a patterned resin film can be obtained.

The developer that can be used is not particularly limited, but in the present embodiment, an alkaline aqueous solution is preferable. Specifically, aqueous solution of inorganic alkali such as sodium hydroxide, sodium carbonate, sodium silicate, ammonia etc., aqueous solution of organic amine such as ethylamine, diethylamine, triethylamine, triethanolamine etc., tetramethyl ammonium hydroxide, tetrabutyl ammonium hydroxide etc. And aqueous solutions of quaternary ammonium salts. For example, a water-soluble organic solvent such as methanol or ethanol, or a surfactant may be added to the developer.
As a developing solution, tetramethyl ammonium hydroxide aqueous solution is preferable. The concentration of tetramethylammonium hydroxide in this aqueous solution is preferably 0.5 to 10% by mass, more preferably 1 to 5% by mass.

  After the development step, the developer may not be washed with the rinse solution, but if necessary, the developer may be removed by washing with the rinse solution. Examples of the rinse solution include distilled water, methanol, ethanol, isopropanol, propylene glycol monomethyl ether and the like. You may use these individually or in combination of 2 or more types.

FIG. 2 shows an example of a process cross-sectional view of a manufacturing process of the electronic device 100.
In step 5, as shown in FIGS. 2A and 2B, the first circuit board 102 and the second circuit are formed via the patterned first resin film 112 and the second resin film 114 (adhesive layer). The substrate 104 is stacked (bonded), and the metal bonding portion 130 and the metal layer 132 are electrically connected. At this time, one of the first resin film 112 and the second resin film 114 can be in the B-stage state.

  In step 5, a lamination process such as COW, COC, or WOW can be used. A semiconductor chip formed by dicing the first circuit substrate 102 may be stacked on a wafer-like second circuit substrate 104, and a first semiconductor chip formed by dicing the first circuit substrate 102 may be formed as a second circuit. The substrate 104 may be stacked on a second semiconductor chip formed by dicing.

  In step 6, a cured film can be obtained by heating the laminated resin film. In this embodiment, 150-300 degreeC is preferable and, as for this heating temperature, 170-200 degreeC is more preferable. By setting this temperature range, it is possible to achieve both the rate of the crosslinking reaction and the uniform curing of the entire film. The heating time is not particularly limited but is, for example, in the range of 15 to 300 minutes. This heat treatment can be performed by a hot plate, an oven, a temperature rising oven capable of setting a temperature program, or the like. As atmosphere gas at the time of performing heat processing, it may be air or inert gas, such as nitrogen and argon. Moreover, you may heat under pressure reduction.

The photosensitive adhesive composition of the present embodiment is used in applications of insulating materials such as permanent films, protective films, insulating films, rewiring materials, etc. in electric and electronic devices (electronic devices).
In the electronic device provided with the cured product of the photosensitive adhesive composition of the present embodiment, improvement in production stability and reliability is expected.
Here, "electrical / electronic equipment" refers to semiconductor chips, semiconductor elements, printed wiring boards, electric circuits, display devices such as television receivers and monitors, information communication terminals, light emitting diodes, physical batteries, chemical batteries, etc. Elements, devices, final products, and other general equipment related to electricity that apply engineering technology.

  As mentioned above, although embodiment of this invention was described, these are the illustrations of this invention, and can employ | adopt various structures other than the above. Modifications, improvements and the like within the scope which can achieve the object of the present invention are included in the present invention.

  Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the descriptions of these examples.

(1) Synthesis of Cyclic Olefin Polymer <Synthesis Example 1: Synthesis of Cyclic Olefin Polymer (A-1)>
In a sealable reaction vessel, methyl glycidyl ether norbornene (45.1 g, 250 mmol), 2-norbornene (23.5 g, 250 mmol), 1-butyl hydrogen maleate (51.7 g, 300 mmol), and maleic anhydride ( 24.5 g, 250 mmol) were weighed. Furthermore, 105 g of PGME in which dimethyl 2,2′-azobis (2-methyl propionate) (12.1 g, 53 mmol) was dissolved was added to the reaction vessel, and stirred and dissolved. Next, after removing dissolved oxygen in the system by nitrogen bubbling, the vessel was sealed and allowed to react at 70 ° C. for 16 hours. The reaction mixture was then cooled to room temperature and diluted by adding 202 g of acetone. The diluted solution was poured into a large amount of hexane to precipitate a polymer. Then, the polymer was collected by filtration, further washed with hexane, and vacuum dried at 30 ° C. for 16 hours. The yield of the polymer was 101 g, and the yield was 70%. By the above operation, a cyclic olefin resin (copolymer 1) having a repeating unit represented by the following formula (A-1) having a weight average molecular weight Mw of 6300 was obtained.

Synthesis Example 2 Synthesis of Cyclic Olefin Polymer (A-2)
In an appropriately sized reaction vessel equipped with a stirrer and a condenser, 122.4 g (1.25 mol) of maleic anhydride, 117.6 g (1.25 mol) of 2-norbornene and dimethyl 2,2'-azobis (2- 11.5 g (0.05 mol) of methyl propionate was weighed and dissolved in 150.8 g of methyl ethyl ketone and 77.7 g of toluene The solution was purged with nitrogen for 10 minutes to remove oxygen and then removed. The mixture was heated at 60 ° C. for 16 hours while being stirred (polymerization step).
Then, after adding 320 g of MEK to this solution, it is added to a suspension of sodium hydroxide 12.5 g, 0.31 mol), 463.1 g (6.25 mol) of butanol, and 480 g of toluene to form a cyclic structure derived from maleic anhydride The mixture was mixed at 45 ° C. for 3 hours so that 50% or more of the repeating units in the body were closed. Then, the mixed solution was cooled to 40 ° C., treated with 49.0 g (0.94 mol) of a 88 wt% formic acid aqueous solution, and protonated (ring opening step).
Thereafter, MEK and water were added, and the aqueous layer was separated to remove inorganic residues. Subsequently, methanol and hexane were added and the organic layer was separated to remove the unreacted monomer. Propylene glycol-1-monomethyl ether-2-acetate (PGMEA) was further added, and methanol and butanol in the system were distilled off under reduced pressure until the residual amount was less than 1%. The PGMEA solution of cyclic olefin resin (copolymer 2) which has a repeating unit shown by following formula (A-2) whose weight average molecular weight Mw is 13,700 by this was obtained.

Synthesis Example 3 Synthesis of Cyclic Olefin Polymer (A-3)
In a sealable reaction vessel, norbornene carboxylic acid (30.4 g, 220 mmol), methyl glycidyl ether norbornene (57.7 g, 320 mmol), maleimide (24.3 g, 250 mmol), and cyclohexyl maleimide (44.8 g, 250 mmol) Was weighed. Furthermore, 113 g of PGME in which dimethyl 2,2′-azobis (2-methyl propionate) (12.0 g, 52 mmol) was dissolved was added to the reaction vessel, and stirred and dissolved. Next, after removing dissolved oxygen in the system by nitrogen bubbling, the vessel was sealed and allowed to react at 70 ° C. for 16 hours. The reaction mixture was then cooled to room temperature and diluted by adding 200 g of acetone. The diluted solution was poured into a large amount of hexane to precipitate a polymer. Next, the polymer was collected by filtration and further washed with hexane, and then vacuum dried at 30 ° C. for 16 hours to obtain a cyclic olefin resin (A-3). The yield of the polymer was 126 g, and the yield was 80%. By the above operation, a cyclic olefin resin (copolymer 3) having a repeating unit represented by the following formula (A-3) and having a weight average molecular weight Mw of 8500 was obtained.

(2) Preparation of Photosensitive Adhesive Composition <Preparation of Photosensitive Adhesive Composition in Each Example and Comparative Example>
The raw material of each component mix | blended according to following Table 1 was dissolved in a propylene glycol monomethyl ether acetate (PGMEA), and the non-volatile component obtained the mixed solution of 33 mass%. Thereafter, the mixed solution was filtered with a 0.2 μm nylon filter to obtain a positive photosensitive adhesive composition.
The detail of the raw material of each component in Table 1 is as follows.

・ Polymer (A)
(A-1): Copolymer 1 represented by the following formula (cyclic olefin resin synthesized in the above Synthesis Example 1)
(A-2): Copolymer 2 represented by the following formula (cyclic olefin resin synthesized in the above Synthesis Example 2)
(A-3): Copolymer 3 represented by the following formula (cyclic olefin resin synthesized in the above Synthesis Example 3)
(A-4): Phenolic resin (cresol novolak resin, PR-56001, manufactured by Sumitomo Bakelite Co., Ltd., polystyrene equivalent weight average molecular weight (Mw) = 11,000)
(A-5): methacrylic acid / styrene / glycidyl glycidyl / dicyclopentadienyl methacrylate copolymer (charged molar ratio 30: 10: 50: 10), (manufactured by Daitoke Mix Co., Ltd.)

Photosensitizer (B)
(B-1): Diazoquinone compound (GPA-250, manufactured by Daitoke Mix Co., Ltd.) represented by the following formula

· Crosslinking agent (C)
(C-1): Epoxy resin represented by the following formula (EXA-830 CRP, manufactured by Daiso Corporation)
(C-2): Epoxy resin represented by the following formula (TECHMORE VG3101L, manufactured by PRINTEC Co., Ltd.)
(C-3): Epoxy resin represented by the following formula (Celloxide 2021P, manufactured by Daicel Corporation)
(C-4): Oxetane compound represented by the following formula (Aron oxetane OXT-121, manufactured by Toa Gosei Co., Ltd.)

・ Phenolic resin (D)
(D-1): Phenolic compound represented by the following formula (Tris P-PA-MF, manufactured by Honshu Kagaku Co., Ltd., the following structure)
(D-2): Phenolic compound represented by the following formula (TekP-4HBPA, manufactured by Honshu Kagaku Co., Ltd., structure shown below)
(D-3): Phenol resin represented by the following formula (PR-55959, manufactured by Sumitomo Bakelite Co., Ltd.)

· Adhesion aid (E)
(E-1): Silane coupling agent (KBM-403E, manufactured by Shin-Etsu Chemical Co., Ltd.)

. Surfactant (F)
(F-1): fluorine atom-containing nonionic surfactant (Megafuck R41, manufactured by DIC Corporation, lipophilic group-containing oligomer)

(3) Evaluation of photosensitive adhesive composition About the obtained photosensitive adhesive composition, evaluation was implemented based on the following evaluation items. The evaluation results are shown in Table 1.

<Evaluation of sensitivity>
The prepared photosensitive adhesive compositions were each coated on an 8-inch silicon wafer using a spin coater. After coating, pre-baking was carried out at 110 ° C. for 3 minutes on a hot plate to obtain a coating having a film thickness of about 3.5 μm.
The i-line was irradiated to this coating film through a mask (a residual pattern of 0.5 to 100 μm and a cut pattern are drawn) manufactured by Letterpress Printing Co., Ltd. For irradiation, an i-line stepper (Nikon Corporation NSR-4425i) was used.
Thereafter, the exposed portion was dissolved and removed by performing paddle development twice for 30 seconds by using a 2.38% aqueous solution of tetramethylammonium hydroxide as a developing solution. Then, it was rinsed with pure water for 10 seconds.
Patterning evaluation was performed a plurality of times while changing the exposure amount, and the minimum exposure amount at which a via pattern of 5 μm in width was formed by a mask opening of 5 μm in width was defined as sensitivity (mJ / cm ² ).
The sensitivity should be small from the viewpoint of throughput, but if it is 500 mJ / cm ² or less, it can be used practically without any problem. The evaluation results are shown in Table 1.

<Evaluation of post-development resolution>
A pattern was formed in the same manner as in <Evaluation of sensitivity> except that exposure was performed with the above-mentioned energy of “minimum exposure amount” +100 mJ / cm ² . The minimum open via size at this time was evaluated as a pattern resolution after development (μm). The resolution should be as small as possible to create fine wiring. The evaluation results are shown in Table 1.

<Evaluation of resolution after curing>
The film-coated wafer obtained in the above <Evaluation of post-development resolution> is heated stepwise with an oven at 150 ° C. for 30 minutes and at 170 ° C. for 60 minutes while keeping the oxygen concentration at 1000 ppm or less. A cured film of the agent composition was obtained. The minimum open via size at this time was evaluated as a pattern resolution (μm) after curing. The resolution should be as small as possible to create fine wiring. The evaluation results are shown in Table 1.

<Measurement of dielectric constant>
The prepared photosensitive adhesive compositions were each coated on an 8-inch silicon wafer using a spin coater. After coating, pre-baking was carried out at 110 ° C. for 3 minutes on a hot plate to obtain a coating having a film thickness of about 10 μm. The coated film was cured under a nitrogen atmosphere at a temperature of 200 ° C. for 90 minutes while maintaining the oxygen concentration at 1000 ppm or less to obtain a cured film (sample). The dielectric constant at 25 ° C. and a frequency of 1 GHz was measured for the obtained sample using a cylindrical cavity resonator method. The evaluation results are shown in Table 1.

<Preparation of coating film for evaluation of adhesion after bonding>
The prepared photosensitive adhesive compositions were each coated on an 8-inch silicon wafer using a spin coater. After coating, pre-baking was carried out at 110 ° C. for 3 minutes on a hot plate to obtain a coating having a film thickness of about 3.5 μm. The obtained coated film was subjected to paddle development for 30 seconds × 2 times using a 2.38% aqueous solution of tetramethylammonium hydroxide as a developing solution. Next, this coating was heated at 150 ° C. for 3 minutes to obtain a coating for evaluation of adhesion after bonding.

<Sample preparation for adhesion evaluation A after bonding (coated film / coated film)>
The coated wafer obtained in the above <Preparation of a coating film for adhesion evaluation after bonding> is cut out using a dicing saw, and a 5 mm × 5 mm square substrate for evaluation (upper chip) and a 10 mm × 10 mm square A square evaluation substrate (lower chip) was produced.
Next, using a flip chip bonder (NM-SB50A (Panasonic Corporation), the upper chip is placed on the lower chip under the conditions of a temperature of 220 ° C., a time of 15 seconds, and a pressure of 25 N so that the coated film surface and the coated film surface contact. The chip was bonded to obtain a bonded sample, which was then cured under conditions of 200 ° C. for 90 minutes while maintaining the oxygen concentration at 1000 ppm or less, to obtain a sample for bonding evaluation A after bonding.

<Evaluation of adhesion A after bonding>
An Al pin with an epoxy resin (評 価 5.2 mm, made by Phototechnica Co., Ltd.) is placed on the top chip of the sample for post-bonding adhesion evaluation A obtained in the above <Sample preparation for post-bonding adhesion evaluation A> at 150 ° C. It heat-treated for 1 hour and obtained adhesion sample A with Al pin.
The obtained adhesion sample A with Al pin was subjected to a tensile test using a tensile tester (Tensilon RTC-1210A, manufactured by Orientec Co., Ltd.), and the breaking stress at the time of breakage was measured. The results are shown in Table 1. The breaking stress should be high from the viewpoint of reliability.

<Sample preparation for adhesion evaluation B after bonding (coated film / substrate with nitride film)>
After the bonding, the lower chip of the sample for adhesion evaluation A was changed to a silicon wafer with a nitride film, and the bonding temperature was changed to 250 ° C. A sample for adhesion evaluation B was obtained.

<Evaluation of Adhesiveness B after Bonding>
An Al pin with an epoxy resin (評 価 5.2 mm, made by Phototechnica Co., Ltd.) is placed on the top chip of the sample for bonding evaluation B after bonding obtained in the above <Preparation of samples for bonding evaluation B after bonding> at 150 ° C. It heat-treated for 1 hour and obtained adhesion sample B with Al pin.
The obtained adhesion sample B with Al pin was subjected to a tensile test using a tensile tester (Tensilon RTC-1210A, manufactured by Orientec Co., Ltd.), and the breaking stress at the time of breakage was measured. The results are shown in Table 1. The breaking stress should be high from the viewpoint of reliability.

As compared with Comparative Examples 1 and 2, the photosensitive adhesive compositions of Examples 1 to 7 are based on the results of the adhesiveness A on the resin film having excellent adhesion between the films, and the results of the adhesiveness B on the substrate adhesiveness. It turned out that an excellent resin film (adhesive layer) can be realized. Such a photosensitive adhesive composition can be suitably used for the formation of an organic insulating layer (cured film) for bonding the first circuit substrate and the second circuit substrate therebetween for adhesion.
In addition, the photosensitive adhesive compositions of Examples 1 to 7 have no problem in sensitivity practically, and compared with Comparative Examples 1 and 2, from the result of the pattern resolution after curing, the resolution of the opening pattern after curing was excellent. It turned out that a cured film (organic insulating layer) can be realized. In addition, it turned out that the photosensitive adhesive composition of Examples 1-7 can implement | achieve the cured film in which a relative dielectric constant is small compared with Comparative Examples 1 and 2. Such a photosensitive adhesive composition can be suitably used as an organic insulating layer for embedding a metal bonding portion electrically connecting the first circuit board and the second circuit board.

Reference Signs List 100 electronic device 102 first circuit board 104 second circuit board 110 organic insulating layer 112 first resin film 114 second resin film 130 metal bonding portion 132 metal layer

Claims (25)

A photosensitive adhesive composition, which is used to form an organic insulating layer for bonding a first circuit board and a second circuit board between them,
A copolymer having a structural unit A derived from a norbornene-based monomer and a structural unit B derived from maleic anhydride, maleimide or their derivatives;
A photosensitizer,
A crosslinker, and a photosensitive adhesive composition. The photosensitive adhesive composition according to claim 1, wherein
The photosensitive adhesive composition whose said copolymer is equipped with the functional group which carries out the crosslinking reaction with the said crosslinking agent. The photosensitive adhesive composition according to claim 1 or 2, wherein
Photosensitive adhesive composition that is positive-working. The photosensitive adhesive composition according to any one of claims 1 to 3, wherein
The photosensitive adhesive composition in which the said crosslinking agent contains the compound which has a cyclic ether group. The photosensitive adhesive composition according to claim 4, wherein
The photosensitive adhesive composition as described above, wherein the compound having a cyclic ether group comprises an epoxy resin. The photosensitive adhesive composition according to claim 5, wherein
The photosensitive adhesive composition, wherein the epoxy resin comprises an epoxy resin having two or more epoxy groups in one molecule. The photosensitive adhesive composition according to any one of claims 1 to 6, wherein
A photosensitive adhesive composition comprising a phenolic resin. The photosensitive adhesive composition according to claim 7, wherein
The photosensitive adhesive composition, wherein the phenolic resin comprises a phenolic resin having two or more phenolic hydroxyl groups in one molecule. The photosensitive adhesive composition according to any one of claims 1 to 8, wherein
The photosensitive adhesive composition, wherein the photosensitive agent comprises a diazoquinone compound. The photosensitive adhesive composition according to any one of claims 1 to 9, wherein
A photosensitive adhesive composition comprising a cohesion aid. The photosensitive adhesive composition according to any one of claims 1 to 10, wherein
Photosensitive adhesive composition comprising a surfactant. The photosensitive adhesive composition according to any one of claims 1 to 11, wherein
Photosensitive adhesive composition comprising a solvent. The photosensitive adhesive composition according to any one of claims 1 to 12, wherein
The photosensitive adhesive composition whose non-volatile component of the said photosensitive adhesive composition is 1 mass% or more and 50 mass% or less with respect to the said whole photosensitive adhesive composition. The photosensitive adhesive composition according to any one of claims 1 to 13, wherein
The photosensitive adhesive composition whose content of the said copolymer is 20 mass% or more and 80 mass% or less with respect to 100 mass% of non-volatile components of the said photosensitive adhesive composition. The photosensitive adhesive composition according to any one of claims 1 to 14, wherein
The photosensitive adhesive composition, wherein the structural unit B comprises a structural unit represented by the following formula (1).

(In formula (1), R _X and R _Y each independently represent hydrogen or an organic group having 1 to 3 carbon atoms.) The photosensitive adhesive composition according to any one of claims 1 to 15, wherein
The said copolymer is a photosensitive adhesive composition which has structural unit C derived from the ester compound which the acid anhydride ring of maleic anhydride ring-opened. 17. A photosensitive adhesive composition according to claim 16 comprising
The photosensitive adhesive composition whose structural unit C derived from the said ester compound has an aliphatic group. A photosensitive adhesive composition according to any one of the preceding claims, wherein
The photosensitive adhesive composition in which the structural unit A derived from the said norbornene-type monomer contains the structural unit represented by following formula (2).

In formula (2), R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom, a hydroxyl group or an organic group having 1 to 30 carbon atoms, and n is 0, 1 or 2. ) The photosensitive adhesive composition according to any one of claims 1 to 18, wherein
The dielectric constant of the cured film of the photosensitive adhesive composition cured under the conditions of 200 ° C. for 90 minutes in a nitrogen atmosphere at a frequency of 1 GHz measured by the cylindrical cavity resonator method is 3.3 or less. Photosensitive adhesive composition. 20. A photosensitive adhesive composition according to any one of the preceding claims, wherein
The photosensitive adhesive composition, wherein the organic insulating layer embeds a metal bonding portion that electrically connects the first circuit board and the second circuit board. The photosensitive adhesive composition according to claim 20, wherein
Photosensitive adhesive composition, wherein the metal joint is made of copper. A photosensitive adhesive composition according to claim 20 or 21, wherein
A photosensitive adhesive composition, wherein the metal joint has a copper pillar. The photosensitive adhesive composition according to any one of claims 1 to 22, wherein
The first circuit substrate is a first semiconductor chip or a first semiconductor wafer,
A photosensitive adhesive composition, wherein the second circuit substrate is a second semiconductor chip or a second semiconductor wafer. The photosensitive adhesive composition according to any one of claims 1 to 23, wherein
The photosensitive adhesive composition whose thickness of the said organic insulating layer is 10 micrometers or less.   The structure provided with the hardened | cured material of the photosensitive adhesive composition of any one of Claims 1-24.

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