JP6555115B2 - Photosensitive resin material - Google Patents

Description

  The present invention relates to a photosensitive resin material.

  In manufacturing an electronic device, a photosensitive resin composition may be used to manufacture a resin film such as an interlayer insulating film. Examples of techniques relating to such a photosensitive resin composition include those described below.

  Patent Document 1 is a photosensitive resin composition containing a polyimide resin or a precursor thereof, a quinonediazide compound, a solvent and a surfactant, wherein the surfactant has a silicon surfactant and a fluorine atom. This is a technology related to agents.

  Patent Document 2 discloses that 1-100 parts by mass of a photosensitive diazonaphthoquinone compound and 100-1000 parts by mass of an organic solvent with respect to 100 parts by mass of an alkali-soluble phenol resin, polyhydroxystyrene, or a polymer that is a derivative of polyhydroxystyrene. And a photosensitive resin composition containing 0.1 to 20 parts by mass of an adhesion assistant which is an organic compound containing an alkoxysilyl group.

JP 2010-243748 A JP 2008-164816 A

  In recent years, demands for downsizing, high integration, weight reduction, and the like for electronic devices equipped with semiconductor devices are increasing. In view of these requirements, in recent electronic device manufacturing processes, the problem of adhesion between a resin film formed using a photosensitive resin composition and a redistribution metal such as copper has become apparent. Specifically, in the manufacturing process of electronic devices in recent years, when patterning a resin film formed using a photosensitive resin composition, due to the influence of the resin film residue adhered on the rewiring metal, In some cases, such a disadvantage that the adhesion between the resin film and the redistribution metal decreases. In this case, there is a concern that it is difficult to stably manufacture the electronic device.

  Therefore, the present invention provides a photosensitive resin material capable of realizing a resin film having excellent adhesion to a rewiring metal.

According to the present invention, an alkali-soluble resin (A),
A photosensitive agent (B);
A carboximide compound (C) having a molecular structure having a dicarboximide structure represented by the following formula (a), and a photosensitive resin material comprising:
Wherein the photosensitive resin material, 300 ° C., for 30 minutes in conditions, in nitrogen atmosphere, the cured film obtained by curing, it der tensile elongation 20% or more at 23 ° C.,
There is provided a photosensitive resin material in which the carboximide compound (C) contains at least one dicarboximide compound represented by the formula (c) .

(In formula (a), R 1 and R 2 are each an organic group having 1 to 20 carbon atoms, and may be the same or different. R 1 and R 2 are bonded to each other to form a ring structure 1. Or two or more may be formed.)

  ADVANTAGE OF THE INVENTION According to this invention, the photosensitive resin material which can implement | achieve the resin film excellent in adhesiveness with a rewiring metal can be provided.

It is sectional drawing which shows an example of the electronic device which concerns on this embodiment.

  Hereinafter, embodiments will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  The photosensitive resin material according to the present embodiment includes an alkali-soluble resin (A), a photosensitive agent (B), and a carboxylimide compound (C) having a molecular structure having a dicarboximide structure represented by the following formula (a). ) And.

(In formula (a), R 1 and R 2 are each an organic group having 1 to 20 carbon atoms, and may be the same or different. R 1 and R 2 are bonded to each other to form a ring structure 1. Or two or more may be formed.)

  As described in the section of the problem to be solved by the invention, in recent years, there has been an increasing demand for downsizing, high integration, weight reduction, and the like for an electronic device in which a semiconductor device is mounted. In recent electronic device manufacturing processes, the problem of adhesion between a resin film formed using a photosensitive resin composition and a rewiring metal such as copper has become apparent. Specifically, in the manufacturing process of electronic devices in recent years, when patterning a resin film formed using a photosensitive resin composition, due to the influence of the residue of the resin film adhered on the rewiring metal, In some cases, such a disadvantage that the adhesion between the resin film and the redistribution metal decreases. In this case, there is a concern that it is difficult to stably manufacture the electronic device.

Therefore, the present inventor has intensively studied the design guideline in order to provide a photosensitive resin material capable of realizing a resin film having excellent adhesion to the rewiring metal. As a result, the photosensitive resin material is formed using the photosensitive resin material by blending in the photosensitive resin material with the carboxyimide compound (C) having a molecular structure having the dicarboximide structure represented by the above formula (a). It has been found that the adhesion between the prepared resin film and the rewiring metal can be improved. In the present embodiment, based on such knowledge, an alkali-soluble resin (A), a photosensitizer (B), and a carboximide compound comprising a molecular structure having a dicarboximide structure represented by the above formula (a). (C) and the photosensitive resin material containing are implement | achieved.
Therefore, according to this embodiment, it is possible to realize a resin film having excellent adhesion to the redistribution metal, and it is also possible to realize an electronic device having excellent manufacturing stability. The reason is considered to be that according to the photosensitive resin material according to the present embodiment, a resin residue is hardly generated when a resin film formed using the resin material is patterned. Specifically, although the reason is not necessarily clear, according to the photosensitive resin material according to the present embodiment, a carboximide compound having a molecular structure having a dicarboximide structure represented by the above formula (a) ( By blending C), it is considered that the solubility of the cured product of the resin material is improved during patterning, that is, during exposure and development.
Moreover, according to the photosensitive resin material which concerns on this embodiment, not only the initial adhesiveness immediately after manufacture but the adhesiveness after a long-term use can be improved.

  Hereinafter, the structure of the photosensitive resin material which concerns on this embodiment, and the electronic device provided with the permanent film formed using the photosensitive resin material is demonstrated in detail.

  The photosensitive resin material according to the present embodiment is used, for example, to form a permanent film. In this case, a cured film constituting a permanent film can be obtained by curing the photosensitive resin material. In this embodiment, for example, a resin film obtained by applying a photosensitive resin material is patterned into a desired shape by exposure and development, and then the resin film is cured by heat treatment or the like to form a permanent film.

Examples of the permanent film formed using the photosensitive resin material include an interlayer film, a surface protective film, and a dam material. However, the use of the photosensitive resin material is not limited to this.
The interlayer film refers to an insulating film provided in a multilayer structure, and the kind thereof is not particularly limited. Examples of the interlayer film include those used in semiconductor device applications such as an interlayer insulating film constituting a multilayer wiring structure of a semiconductor element and a buildup layer or a core layer constituting a wiring board. Further, as the interlayer film, for example, a flattening film that covers a thin film transistor (TFT) in the display device, a liquid crystal alignment film, and a protrusion provided on a color filter substrate of an MVA (Multi Domain Vertical Alignment) type liquid crystal display device Or what is used in display apparatus uses, such as a partition for forming the cathode of an organic EL element, is also mentioned.

  The surface protective film refers to an insulating film that is formed on the surface of an electronic component or an electronic device and protects the surface, and the type thereof is not particularly limited. Examples of such a surface protective film include a passivation film or a buffer coat layer provided on a semiconductor element, or a cover coat provided on a flexible substrate. Examples of the dam material include a spacer used to form a hollow portion for arranging an optical element or the like on a substrate.

  According to the photosensitive resin material according to the present embodiment, by compounding the resin material with a carboxyimide compound (C) having a molecular structure having a dicarboximide structure represented by the above formula (a), It is possible to realize a resin film having excellent adhesion to the rewiring metal. The adhesion between the resin film and the redistribution metal described above is more preferable by appropriately adjusting, for example, the type and blending ratio of each component contained in the photosensitive resin material and the method for preparing the photosensitive resin material. Can be. Among these, the types of the alkali-soluble resin (A) and the photosensitive agent (B) and the three components (alkali-soluble resin (A), photosensitive agent ( By appropriately adjusting the blending ratios of B) and the above-described carboximide compound (C)), it is possible to further improve the adhesion between the above-described resin film and the rewiring metal.

  For example, the content of the carboxyimide compound (C) in the photosensitive resin material according to the present embodiment is preferably 0.1 parts by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the alkali-soluble resin (A). Yes, more preferably from 1 part by weight to 20 parts by weight, and most preferably from 2 parts by weight to 15 parts by weight. As a result, it is possible to realize a photosensitive resin material having good patterning performance while exhibiting an effect of adhesion to a copper substrate.

  Here, as for the photosensitive resin material which concerns on this embodiment, it is preferable that the cured film obtained by heat-processing the said resin material has the physical property described in the following (1)-(2). This heat treatment is performed for 30 minutes at a temperature of 300 ° C., for example, in a nitrogen atmosphere.

(1) The cured film obtained by heat-treating the photosensitive resin material according to this embodiment preferably has a tensile elongation at 23 ° C. of 5% or more, more preferably 10% or more, and 20%. The above is particularly preferable. Thereby, about the permanent film formed using the photosensitive resin material, the outstanding durability is implement | achieved and a crack, a crack, etc. can be suppressed reliably. Tensile elongation is, for example, a tensile test (stretching speed) in an atmosphere at a temperature of 23 ° C. and a humidity of 55% with respect to a test piece obtained by peeling the cured film obtained by heat-treating a photosensitive resin material from a wafer with hydrofluoric acid or the like. : 0.05 mm / min).

(2) The cured film obtained by heat-treating the photosensitive resin material according to this embodiment preferably has a glass transition temperature of 200 ° C. or higher, and more preferably 250 ° C. or higher. Thereby, a permanent film having excellent adhesion and heat resistance can be realized. The upper limit value of the glass transition temperature is not particularly limited, but can be set to 400 ° C. or lower, for example. The glass transition temperature is, for example, measured at a starting temperature of 30 ° C. using a thermomechanical analyzer for a test piece obtained by peeling the cured film obtained by heat-treating a photosensitive resin material from a wafer with hydrofluoric acid or the like. It is calculated from the results of measurement under the conditions of a range of 30 to 400 ° C. and a heating rate of 5 ° C./min.

  Each of these physical properties can be realized by appropriately adjusting the type and blending ratio of each component contained in the photosensitive resin material.

((A) alkali-soluble resin)
The alkali-soluble resin (A) has an amide bond such as an acrylic resin such as a phenol resin, a polyhydroxystyrene resin, a methacrylic acid resin, or a methacrylic ester resin, a cyclic olefin resin, a polybenzoxazole precursor, and a polyimide precursor. 1 type or 2 types or more selected from the group which consists of the precursor which has, and the resin obtained by dehydrating and ring-closing the said precursor can be included. Among these, the developability, curability, adhesion, film formability of resin films obtained using photosensitive resin materials, and the adhesion and mechanical strength of cured films obtained by curing the above resin films are improved. Is selected from the group consisting of phenol resins, polyhydroxystyrene resins, precursors having amide bonds such as polybenzoxazole precursors and polyimide precursors, and resins obtained by dehydrating and ring-closing the precursors. It is more preferable that 1 type or 2 types or more are included. Among these, from the viewpoint of heat resistance and thermomechanical properties, a precursor (polyamide resin) having an amide bond represented by the following general formula (5) is more preferable.

In formula (5), X and Y are organic groups. R ₁ is a hydroxyl group, —O—R ₃ , an alkyl group, an acyloxy group, or a cycloalkyl group, and when there are a plurality of R _{1 s} , they may be the same or different. R ₂ is a hydroxyl group, a carboxyl group, —O—R ₃ , or —COO—R ₃ , and when there are a plurality of R _{2 s} , they may be the same or different. R ₃ in R ₁ and R ₂ is an organic group having 1 to 15 carbon atoms. When R ₁ has no hydroxyl group, at least one of R ₂ is a carboxyl group. If there is no carboxyl group as R _2, at least one of R ₁ is a hydroxyl group. m is an integer of 0 to 8, and n is an integer of 0 to 8.
In the polyamide resin represented by the general formula (5), X, Y, R _{1 to} R ₃ , m and n may be the same for each repeating unit, or may be different from each other.

The polyamide-based resin represented by the general formula (5) is, for example, a compound selected from diamine, bis (aminophenol), diaminophenol, and the like having a structure containing a group represented by X in the formula (5), Tetracarboxylic acid anhydride, trimellitic acid anhydride, dicarboxylic acid or dicarboxylic acid dichloride, dicarboxylic acid derivative, hydroxydicarboxylic acid, hydroxydicarboxylic acid derivative, etc. having a structure containing the group represented by Y in the formula (5) It is obtained by reacting with a compound selected from: When dicarboxylic acid is used to obtain the polyamide-based resin represented by the general formula (5), 1-hydroxy-1,2,3-benzotriazole is reacted in advance to increase the reaction yield. Dicarboxylic acid derivatives of the active ester type may also be used.
In addition, when the polyamide resin represented by the general formula (5) is heated at, for example, 300 to 400 ° C., the polyamide resin is dehydrated and closed, and as a result, polyimide, polybenzoxazole, or both A resin having excellent heat resistance in the form of a polymer can be obtained.

  Further, the polyamide resin represented by the general formula (5) includes an acid anhydride or a monocarboxylic acid containing an aliphatic group or a cyclic compound group having at least one alkenyl group or alkynyl group at the terminal of the resin. Alternatively, it may be end-capped with an amide derivative. Furthermore, the polyamide-based resin represented by the general formula (5) may have a group in which at least one end of the resin is end-capped with a nitrogen-containing cyclic compound. Thereby, adhesiveness with a metal wiring (especially copper wiring) etc. can be improved.

When the polyamide resin represented by the general formula (5) is a polybenzoxazole precursor, at least one of R ₁ is a hydroxyl group. In this case, a dehydration ring closure occurs between R ₁ and the amide structure by heat dehydration or a dehydration reaction using a catalyst, and a polybenzoxazole resin having an oxazole ring is generated. At this time, the alkali-soluble resin (A) contains at least one of a polybenzoxazole precursor or a polybenzoxazole resin.

Also, if the polyamide resin represented by general formula (5) is a polyimide precursor, at least one of R ₂ is a carboxyl group. In this case, dehydration ring closure (imidization) occurs between R ₂ and the amide structure by heat dehydration or a dehydration reaction using a catalyst, and a polyimide resin is generated. At this time, the alkali-soluble resin (A) includes at least one of a polyimide precursor or a polyimide resin.

  As the phenol resin in the alkali-soluble resin (A), for example, a reaction product of a phenol compound represented by a novolac type phenol resin and an aldehyde compound, or a phenol compound represented by a phenol aralkyl resin and a dimethanol compound or a derivative thereof. A reactant can be used.

  As the hydroxystyrene resin in the alkali-soluble resin (A), a polymerization reaction product or a copolymerization reaction product obtained by radical polymerization, cation polymerization, or anion polymerization of hydroxystyrene, styrene, or a derivative thereof can be used. .

The content of the alkali-soluble resin (A) is preferably 10% by weight or more and 70% by weight or less, and more preferably 15% by weight or more and 65% by weight or less with respect to the entire nonvolatile components of the photosensitive resin material. Yes, and most preferably 20 wt% or more and 50 wt% or less. By making content of alkali-soluble resin (A) more than the said lower limit, sclerosis | hardenability of the photosensitive resin material can be improved. Thereby, the heat resistance, mechanical strength, and durability of the permanent film formed using the photosensitive resin material can be improved. By making content of alkali-soluble resin (A) below the said upper limit, the resolution in lithography can be improved.
In addition, the ratio (weight%) of the non-volatile component in the photosensitive resin material can be measured as follows, for example. First, 1.0 g of a photosensitive resin material is weighed out as a sample in an aluminum cup whose weight (w ₀ ) has been measured. In this case, the total weight of the sample and the aluminum cup and w _1. Next, the aluminum cup is kept in a hot air dryer adjusted to 210 ° C. under normal pressure for 1 hour, and then taken out of the hot air dryer and cooled to room temperature. Next, the total weight (w ₂ ) of the cooled sample and the aluminum cup is measured. And the ratio (weight%) of the non-volatile component in the photosensitive resin material is computed from the following formula | equation.
Formula: Non-volatile content (% by weight) = (w ₂ −w ₀ ) / (w ₁ −w ₀ ) × 100

((B) Photosensitizer)
The photosensitive resin material contains a photosensitive agent (B) as an essential component. As the photosensitizer (B), a compound capable of generating an acid by light can be used. For example, a photosensitive diazoquinone compound, an onium salt such as a diaryl iodonium salt, a triaryl sulfonium salt or a sulfonium borate salt, 2-nitrobenzyl ester A compound, an N-iminosulfonate compound, an imidosulfonate compound, a 2,6-bis (trichloromethyl) -1,3,5-triazine compound, or a dihydropyridine compound can be used. Among these, it is particularly preferable to use a photosensitive diazoquinone compound having excellent sensitivity and solvent solubility. Specific examples of the above-mentioned photosensitive diazoquinone compound include phenol compounds such as 1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide- 5-sulfonic acid ester etc. are mentioned.

  The content of the photosensitive agent (B) is preferably 1 part by weight or more and 50 parts by weight or less, more preferably 5 parts by weight or more and 40 parts by weight or less, with respect to 100 parts by weight of the alkali-soluble resin (A). Yes, most preferably 8 parts by weight or more and 35 parts by weight or less. Thereby, it becomes possible to realize a photosensitive resin material having good patterning performance.

(Carboximide compound (C))
The photosensitive resin material which concerns on this embodiment contains the carboxyimide compound (C) which consists of a molecular structure with the dicarboximide structure shown by following formula (a) as an essential component.

(In formula (a), R 1 and R 2 are each an organic group having 1 to 20 carbon atoms, and may be the same or different. R 1 and R 2 are bonded to each other to form a ring structure 1. Or two or more may be formed.)

  The carboximide compound (C) is not particularly limited as long as it is a compound having an unsubstituted dicarboximide group. Specific examples thereof include various compounds represented by the following formula (b).

  Among the various compounds represented by the above formula (b), the carboximide compound (C) is preferably a dicarboximide compound having a ring structure, and has the following formula having a crosslinkable group with the alkali-soluble resin (A). More preferably, it is a dicarboximide compound having a ring structure represented by (c). By carrying out like this, the dicarboximide compound can bridge | crosslink with alkali-soluble resin (A) at the time of hardening, and the photosensitive resin composition more excellent in the viewpoint of the adhesiveness to a metal substrate can be obtained.

((D) Crosslinking agent)
The photosensitive resin material which concerns on this embodiment can further contain a crosslinking agent (D). As a crosslinking agent (D), what is necessary is just a compound which has a group which can react with alkali-soluble resin (A), for example, an epoxy compound, an alkoxymethyl compound, a methylol compound, an oxetane compound etc. are mentioned. Specific examples of the crosslinking agent (D) include allyl glycidyl ether, ethylene glycol diglycidyl ether, bisphenol A type glycidyl ether, bisphenol A type epoxy resin, bisphenol F type epoxy resin, Daicel's Celoxide 2021, Celoxide 2081, and Celoxide. 2083, Celoxide 2085, Celoxide 8000, EHPE-3150 and other epoxy group-containing compounds, 1,4-bis (methoxymethyl) benzene, 4,4′-biphenyldimethanol, 4,4′-bis (methoxymethyl) biphenyl, Methylol or alkoxymethyl group-containing compounds such as TMOM-BP, DML-DP, DMOM-DP, TMOM-BP-MF manufactured by Honshu Chemical Co., Ltd., and Nikalac MX-270, MX-290, MX-370 manufactured by Sanwa Chemical Co., Ltd. 4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, bis [1-ethyl (3-oxetanyl)] methyl ether, 4,4′-bis [(3-ethyl-3-oxetanyl) methoxy And an oxetanyl group-containing compound such as methyl] biphenyl. These may be used individually by 1 type and may be used in combination of 2 or more type. Among these, from the viewpoint of forming a cured film having excellent heat resistance and mechanical properties, methylol or alkoxymethylated compounds are preferred.

  In the photosensitive resin composition according to the present invention, the content of the crosslinking agent (D) is preferably 1 part by weight or more and 100 parts by weight or less with respect to 100 parts by weight of the alkali-soluble resin (A), more preferably. 2 parts by weight or more and 50 parts by weight or less. When the content of the crosslinking agent (D) is within the above range, a cured film excellent in chemical resistance and resolution can be formed, which is preferable.

((E) Adhesion aid)
The photosensitive resin material according to the present embodiment can further include an adhesion assistant (E). As the adhesion aid (E), those containing organosilicon are preferable. Thereby, as above-mentioned, it becomes possible to improve the adhesiveness at the time of image development of a photosensitive resin material, and after hardening. For this reason, it is also possible to realize a more stable electronic device manufacturing. Specific examples of the adhesion assistant (E) include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3- Methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltri Examples thereof include methoxysilane and a silicon compound obtained by reacting an amino group-containing silicon compound with an acid dianhydride or acid anhydride.

  Specific examples of the silicon compound having an amino group include 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, N- (2 -Aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane and the like. These may be used individually by 1 type and may be used in combination of 2 or more type.

  Specific examples of the acid dianhydride or acid anhydride include maleic anhydride, chloromaleic anhydride, cyanomaleic anhydride, cytoconic acid, phthalic anhydride, pyromellitic anhydride, 4,4′-biphthalic acid diacid. Anhydrides, 4,4′-oxydiphthalic dianhydride, 4,4′-carbonyldiphthalic anhydride and the like can be mentioned. These may be used individually by 1 type and may be used in combination of 2 or more type.

  The content of the adhesion assistant (E) is preferably 0.05 parts by weight or more and 50 parts by weight or less, more preferably 0.1 parts by weight or more with respect to 100 parts by weight of the alkali-soluble resin (A). More preferably, it is 20 parts by weight or less. When the content of the adhesion assistant (E) is within the above range, both the adhesion to the substrate and the preservability of the photosensitive resin composition can be suitably achieved.

((F) Surfactant)
The photosensitive resin material according to the present embodiment may contain a surfactant (F). The surfactant (F) includes, for example, a compound containing a fluorine group (for example, a fluorinated alkyl group) or a silanol group, or a compound having a siloxane bond as a main skeleton. In the present embodiment, as the surfactant (F), it is more preferable to use a fluorosurfactant or a silicone surfactant, and it is particularly preferable to use a fluorosurfactant. Specific examples of such a fluorosurfactant include Megafac F-171, F-173, F-444, F-470, F-471, F-475, F-482, F-477, manufactured by DIC Corporation. Examples thereof include F-554, F-556 and F-557, Novec FC4430 and FC4432 manufactured by Sumitomo 3M Limited.

  The content of the surfactant (F) is preferably 0.01 parts by weight or more and 5 parts by weight or less, and more preferably 0.03 parts by weight or more with respect to 100 parts by weight of the alkali-soluble resin (A). 2 parts by weight or less, and most preferably 0.03 parts by weight or more and 1 part by weight or less. Thereby, the flatness of the resin film obtained using the photosensitive resin material can be effectively improved.

((G) curing agent)
The photosensitive resin material according to this embodiment may contain a curing agent (G). A hardening | curing agent (G) accelerates | stimulates reaction with a crosslinking agent (D) and another component, such as a crosslinking reaction produced between alkali-soluble resin (A) and a crosslinking agent (D). For this reason, it becomes possible to improve the reactivity of the photosensitive resin material by including a hardening | curing agent (G).

  A hardening | curing agent (G) can contain the 1 type (s) or 2 or more types selected from the compound which generate | occur | produces an acid with a heat | fever, for example, the heterocyclic compound containing nitrogen, for example. Examples of the nitrogen-containing hetero five-membered ring compound used as the curing agent (G) include pyrrole, pyrazole, imidazole, 1,2,3-triazole, and 1,2,4-triazole. Examples of the compound that generates an acid by heat used as the curing agent (G) include sulfonium salts, iodonium salts, phosphates, borates, borates, and salicylates. Among these, the viewpoint of containing a compound that generates an acid by heat improves the low-temperature curability and stability with time of the photosensitive resin material and the balance in improving the adhesion of the photosensitive resin material during development and after curing. Is particularly preferable.

  The content of the curing agent (G) is preferably 0.3 parts by weight or more and 10 parts by weight or less, more preferably 1 part by weight or more and 7 parts by weight with respect to 100 parts by weight of the alkali-soluble resin (A). The most preferred is 1.5 to 5 parts by weight. When the content of the curing agent (G) is within the above range, it is possible to more effectively improve the balance between reactivity and stability over time in the photosensitive resin material. Moreover, it can also contribute to the adhesive improvement at the time of development of the photosensitive resin material and after hardening.

(Solution Accelerator (H))
The photosensitive resin material according to this embodiment may contain a dissolution accelerator (H). The dissolution accelerator (H) is a component capable of improving the solubility of the exposed portion of the coating film formed using the photosensitive resin composition in the developer and improving scum during patterning. As the dissolution accelerator (H), a compound having a phenolic hydroxyl group is preferable.

  Moreover, the photosensitive resin material which concerns on this embodiment may contain the organic solvent, for example. In this case, the photosensitive resin material has a varnish shape, for example. Such organic solvents include, for example, N-methyl-2-pyrrolidone, γ-butyrolactone, 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, Propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl-1,3-butylene glycol acetate, 1,3-butylene glycol-3-monomethyl ether, methyl pyruvate, and ethyl pyruvate and methyl-3- One or more selected from methoxypropionate and the like are included.

  Moreover, the photosensitive resin material which concerns on this embodiment may further contain 1 type, or 2 or more types among additives, such as antioxidant, a filler, and a sensitizer, as needed.

Next, an example of the electronic device 100 will be described.
The electronic device 100 according to the present embodiment includes a cured film obtained by curing the above-described photosensitive resin material. Thereby, it is possible to realize the electronic device 100 excellent in manufacturing stability. The cured film obtained by curing the photosensitive resin material is used as a permanent film constituting the electronic device 100 such as an interlayer film, a surface protective film, or a dam material.

FIG. 1 is a cross-sectional view illustrating an example of an electronic device 100 according to the present embodiment.
An electronic device 100 shown in FIG. 1 is, for example, a semiconductor chip. In this case, for example, a semiconductor package can be obtained by mounting the electronic device 100 on the wiring board via the bumps 52. The electronic device 100 includes a semiconductor substrate provided with a semiconductor element such as a transistor, and a multilayer wiring layer provided on the semiconductor substrate (not shown). An interlayer insulating film 30 and an uppermost layer wiring 34 provided on the interlayer insulating film 30 are provided in the uppermost layer of the multilayer wiring layer. The uppermost layer wiring 34 is made of, for example, Al. Further, a passivation film 32 is provided on the interlayer insulating film 30 and the uppermost layer wiring 34. An opening through which the uppermost layer wiring 34 is exposed is provided in a part of the passivation film 32.

  A rewiring layer 40 is provided on the passivation film 32. The rewiring layer 40 includes an insulating layer 42 provided on the passivation film 32, a rewiring 46 provided on the insulating layer 42, an insulating layer 44 provided on the insulating layer 42 and the rewiring 46, Have An opening connected to the uppermost layer wiring 34 is formed in the insulating layer 42. The rewiring 46 is formed on the insulating layer 42 and in an opening provided in the insulating layer 42, and is connected to the uppermost layer wiring 34. The insulating layer 44 is provided with an opening connected to the rewiring 46.

  In the present embodiment, one or more of the passivation film 32, the insulating layer 42, and the insulating layer 44 can be constituted by, for example, a cured film formed by curing the above-described photosensitive resin material. In this case, for example, the passivation film 32, the insulating layer 42, or the insulating layer 44 is formed by patterning by exposing the coating film formed of the photosensitive resin material to ultraviolet rays and performing development, followed by patterning by heating. It is formed.

  Bumps 52 are formed in the openings provided in the insulating layer 44 via, for example, an UBM (Under Bump Metallurgy) layer 50. The electronic device 100 is connected to a wiring board or the like via bumps 52, for example.

２．前記カルボキシイミド化合物（Ｃ）の含有量が、前記アルカリ可溶性樹脂（Ａ）１００重量部に対して０．１重量部以上３０重量部以下である、１．に記載の感光性樹脂材料。
３．前記アルカリ可溶性樹脂（Ａ）が、ポリイミド及びその前駆体、ポリベンゾオキサゾール及びその前駆体、フェノール樹脂、ポリヒドロキシスチレン樹脂からなる群より選択される１種または２種以上を含む、１．または２．に記載の感光性樹脂材料。
４．前記カルボキシイミド化合物（Ｃ）の前記分子構造中に環構造を含む、１．乃至３．のいずれか一つに記載の感光性樹脂組成物。
５．架橋剤（Ｄ）をさらに含む、１．乃至４．のいずれか一つに記載の感光性樹脂材料。
６．密着助剤（Ｅ）をさらに含む、１．乃至５．のいずれか一つに記載の感光性樹脂材料。
７．界面活性剤（Ｆ）をさらに含む、１．乃至６．のいずれか一つに記載の感光性樹脂材料。
８．層間膜、表面保護膜、またはダム材として用いられる永久膜を形成するための材料である、１．乃至７．のいずれか一つに記載の感光性樹脂材料。 It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
Hereinafter, examples of the reference form will be added.
1. An alkali-soluble resin (A);
A photosensitive agent (B);
A photosensitive resin material comprising: a carboximide compound (C) having a molecular structure having a dicarboximide structure represented by the following formula (a).
(In formula (a), R 1 and R 2 are each an organic group having 1 to 20 carbon atoms, and may be the same or different. R 1 and R 2 are bonded to each other to form a ring structure 1. Or two or more may be formed.)

2. The content of the carboximide compound (C) is 0.1 part by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the alkali-soluble resin (A). The photosensitive resin material as described in 2.
3. The alkali-soluble resin (A) includes one or more selected from the group consisting of polyimide and its precursor, polybenzoxazole and its precursor, phenol resin, and polyhydroxystyrene resin. Or 2. The photosensitive resin material as described in 2.
4). A ring structure is included in the molecular structure of the carboximide compound (C). To 3. The photosensitive resin composition as described in any one of these.
5. Further comprising a crosslinking agent (D) To 4. The photosensitive resin material as described in any one of these.
6). Further comprising an adhesion assistant (E). To 5. The photosensitive resin material as described in any one of these.
7). Further comprising a surfactant (F) To 6. The photosensitive resin material as described in any one of these.
8). A material for forming a permanent film used as an interlayer film, a surface protective film, or a dam material. To 7. The photosensitive resin material as described in any one of these.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited to this.

  First, the alkali-soluble resin (A), the photosensitizer (B), and the adhesion assistant (E) used in each example and each comparative example were synthesized by the following method.

<Synthesis Example 1: Alkali-soluble resin (A-1)>
In a four-necked glass separable flask equipped with a thermometer, a stirrer, a raw material inlet and a dry nitrogen gas inlet tube, 21.43 g (0.083 mol) of diphenyl ether-4,4′-dicarboxylic acid and 1-hydroxy- 40.87 g (0.083 mol) of a mixture of dicarboxylic acid derivatives obtained by reacting 22.43 g (0.166 mol) of 1,2,3-benzotriazole monohydrate with hexafluoro-2,2 -36.62 g (0.100 mol) of bis (3-amino-4-hydroxyphenyl) propane was added, and 296.96 g of N-methyl-2-pyrrolidone was added and dissolved. Then, it was made to react at 75 degreeC for 15 hours using the oil bath. Next, 6.98 g (0.0425 mol) of 3,6-endomethylene-1,2,3,6-tetrahydrophthalic anhydride dissolved in 34.88 g of N-methyl-2-pyrrolidone was added. The reaction was terminated by stirring for a period of time.

  Next, after filtering the obtained reaction mixture, the reaction mixture was poured into a solution of water / isopropanol = 3/1 (volume ratio), and the precipitate was collected by filtration and thoroughly washed with water. The target alkali-soluble resin (A-1) was obtained by drying under vacuum. The obtained alkali-soluble resin (A-1) had a weight average molecular weight of 13040.

<Synthesis Example 2: Alkali-soluble resin (A-2)>
To a four-necked glass separable flask equipped with a thermometer, stirrer, raw material inlet and dry nitrogen gas inlet tube, 30.0 g of 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane ( 0.082 mol) was added and dissolved by adding 400 ml of acetone. Next, 12.4 g (0.18 mol) of p-nitrobenzoyl chloride dissolved in 100 mL of acetone was added dropwise over 30 minutes while cooling so that the temperature was less than 20 ° C. to obtain a mixture. After the dropwise addition of p-nitrobenzoyl chloride was completed, the temperature of the mixture was heated to 40 ° C., and then stirred for 2 hours. Next, 30.0 g (0.218 mol) of potassium carbonate was gradually added and further stirred for 2 hours. The above mixture was then further stirred at room temperature for 18 hours. Thereafter, an aqueous sodium hydroxide solution was gradually added while vigorously stirring the mixture, and then the mixture was heated to 55 ° C. and further stirred for 30 minutes. After completion of the stirring, the mixture was cooled to room temperature, 37% by weight hydrochloric acid aqueous solution and 500 ml of water were added, and the pH of the solution was adjusted to be in the range of 6.0 to 7.0. Subsequently, the filtrate obtained by separating the obtained precipitates by filtration was washed with water and then dried at a temperature of 60 to 70 ° C., and bis-N, N ′-(p-nitrobenzoyl) hexafluoro- A solid of 2,2-bis (4-hydroxyphenyl) propane was obtained.

  Next, 316 g of acetone and 158 g of methanol were added to 51.0 g of the obtained bis-N, N ′-(p-nitrobenzoyl) hexafluoro-2,2-bis (4-hydroxyphenyl) propane solid, By heating to 50 ° C., the solid was completely dissolved. 300 mL of 50 ° C. pure water was added thereto over 30 minutes, and then heated to 65 ° C. Then, the crystal | crystallization which precipitated by cooling slowly to room temperature is filtered, and this crystal | crystallization is refine | purified by drying at 70 degreeC, Bis-N, N'- (p-nitrobenzoyl) hexafluoro-2,2- Bis (4-hydroxyphenyl) propane was obtained.

  Into a 1 L flask, 20 g of bis-N, N ′-(p-nitrobenzoyl) hexafluoro-2,2-bis (4-hydroxyphenyl) propane obtained by the above-described method was placed, and 5% palladium-carbon catalyst. 1.0 g and 180.4 g of ethyl acetate were added to make a suspension. Hydrogen gas was purged there, and the mixture was shaken for 35 minutes while being heated to 50 to 55 ° C. to carry out a reduction reaction. After completion of the reaction, the suspension was cooled to 35 ° C. and then the suspension was purged with nitrogen. After removing the catalyst by filtration, the filtrate was subjected to an evaporator to evaporate the solvent. The obtained product was dried at 90 ° C. to obtain bis-N, N ′-(p-aminobenzoyl) hexafluoro-2,2-bis (4-hydroxyphenyl) propane.

  Bis-N, N ′-(p-aminobenzoyl) hexafluoro obtained by the above-described method was added to a four-necked glass separable flask equipped with a thermometer, a stirrer, a raw material inlet and a dry nitrogen gas inlet tube. 14.5 g (0.024 mol) of -2,2-bis (4-hydroxyphenyl) propane was added, 40 g of γ-butyrolactone was added and dissolved, and the mixture was cooled to 15 ° C. with stirring. Thereto, 6.8 g (0.022 mol) of 4,4′-oxydiphthalic anhydride and 12.0 g of γ-butyrolactone were added and stirred at 20 ° C. for 1.5 hours. Thereafter, the mixture was heated to 50 ° C. and stirred for 3 hours. Then, 5.2 g (0.044 mol) of N, N-dimethylformamide dimethylacetal and 10.0 g of γ-butyrolactone were added, and the mixture was further stirred at 50 ° C. for 1 hour. The objective alkali-soluble resin (A-2) was obtained by cooling to room temperature after completion | finish of reaction. The obtained alkali-soluble resin (A-2) had a weight average molecular weight of 13,200.

<Synthesis Example 3: Alkali-soluble resin (A-3)>
In a four-neck glass round bottom flask equipped with a thermometer, a stirrer, a raw material inlet and a dry nitrogen gas inlet tube, 64.9 g (0.60 mol) of m-cresol and p-cresol 43. 3 g (0.40 mol), 30 wt% formaldehyde aqueous solution 65.1 g (formaldehyde content: 0.65 mol), and oxalic acid dihydrate 0.63 g (0.005 mol) were charged and then immersed in an oil bath. The polycondensation reaction was performed at 100 ° C. for 4 hours while the reaction solution was refluxed. Subsequently, after raising the temperature of the oil bath to 200 ° C. over 3 hours, the pressure in the flask was reduced to 50 mmHg or less to remove moisture and volatile matter. Then, the target alkali-soluble resin (A-3) was obtained by cooling resin to room temperature. The obtained alkali-soluble resin (A-3) had a weight average molecular weight of 3,200.

<Synthesis Example 4: Photosensitizer (B)>
In a four-necked separable flask equipped with a thermometer, a stirrer, a raw material inlet, and a dry nitrogen gas inlet tube, 11.04 g (0.026 mol) of phenol represented by the following formula (P-1), 2-Naphthoquinone-2-diazide-4-sulfonyl chloride 18.81 g (0.070 mol) and acetone 170 g were added and stirred to dissolve.
Next, a mixed solution of 7.78 g (0.077 mol) of triethylamine and 5.5 g of acetone was slowly added dropwise while cooling the flask with a water bath so that the temperature of the reaction solution did not exceed 35 ° C. After reacting for 3 hours at room temperature, 1.05 g (0.017 mol) of acetic acid was added and reacted for another 30 minutes. Subsequently, after filtering the reaction mixture, the filtrate was put into a mixed solution of water / acetic acid (990 ml / 10 ml). Next, the precipitate was collected by filtration, thoroughly washed with water, and then dried under vacuum. As a result, a photosensitizer (B) represented by the structure of the following formula (Q-1) was obtained.

<Synthesis Example 5: Adhesion aid (E-2)>
Cyclohexene-1,2-dicarboxylic anhydride (45.6 g, 300 mmol) was dissolved in γ-butyrolactone (970 g) in a suitably sized reaction vessel equipped with a stirrer and a condenser, and the temperature was kept at 30 ° C. in a thermostatic bath. Adjusted. Subsequently, 3-aminopropyltriethoxysilane (62 g, 280 mmol) was charged into the dropping funnel and dropped into the solution over 60 minutes. After completion of dropping, the mixture was stirred under conditions of 30 ° C. for 18 hours to obtain a silane coupling agent represented by the following formula (9) as an adhesion assistant (E-2).

<Synthesis Example 6: Adhesion aid (E-3)>
In a suitably sized reaction vessel equipped with a stirrer and a condenser, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride (32.2 g, 100 mmol) was dissolved in γ-butyrolactone (669 g). The temperature was adjusted to 30 ° C. in a thermostatic bath. Subsequently, 3-aminopropyltriethoxysilane (42.1 g, 190 mmol) was charged into the dropping funnel and dropped into the solution over 60 minutes. After completion of dropping, the mixture was stirred under conditions of 30 ° C. for 18 hours to obtain a silane coupling agent represented by the following formula (10) as an adhesion assistant (E-3).

  The raw material components used in each example and each comparative example are shown below.

<Alkali-soluble resin (A)>
(A-1) Polyamide resin obtained by Synthesis Example 1 above.
(A-2) Polyamide resin obtained in Synthesis Example 2 above.
(A-3) A phenol resin obtained by Synthesis Example 3 above.

<Photosensitive agent (B)>
-The diazonaphthoquinone compound obtained in Synthesis Example 4 above

<Carboximide compound (C)>
(C-1) cis-1,2,3,6-tetrahydrophthalimide (manufactured by Tokyo Chemical Industry Co., Ltd.)
(C-2) 5-norbornene-2,3-dicarboximide (manufactured by Tokyo Chemical Industry Co., Ltd.)
(C-3) Maleimide (manufactured by Tokyo Chemical Industry Co., Ltd.)
(C-4) 4-Aminophthalimide (manufactured by Tokyo Chemical Industry Co., Ltd.)
(C-5) Phthalimide (manufactured by Tokyo Chemical Industry Co., Ltd.)
(C-6) Bistrifluoroacetamide (manufactured by Tokyo Chemical Industry Co., Ltd.)

  Moreover, the molecular structure of the said carboximide compound (C-1)-(C-6) is as showing to following formula (11).

<Crosslinking agent (D)>
(D-1) Nikarac MX-270 (manufactured by Sanwa Chemical Co., Ltd.)
(D-2) TML-BPA (Honshu Chemical Co., Ltd.)

  The molecular structures of the crosslinking agents (D-1) and (D-2) are as shown in the following formula (12).

<Adhesion aid (E)>
(E-1) 3-Methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Silicone)
(E-2) Silane coupling agent obtained by Synthesis Example 5 (E-3) Silane coupling agent obtained by Synthesis Example 6

<Surfactant (F)>
・ Fluorosurfactant (Sumitomo 3M, FC4430)

<Preparation of photosensitive resin composition according to each example and each comparative example>
About each of Examples 1-11, and Comparative Examples 1-2, what mix | blended each component according to the compounding quantity shown in Table 1 was dissolved in (gamma) -butyrolactone so that the viscosity after a mixing might be set to about 500 mPa * s. Stir in a nitrogen atmosphere. Then, the varnish-like photosensitive resin composition was obtained by filtering with the polyethylene filter with a hole diameter of 0.2 micrometer. In addition, as for the unit of the compounding quantity shown in following Table 1, all are a weight part.

  About the obtained photosensitive resin composition, the measurement and evaluation shown below were performed.

(Evaluation item)
Copper substrate adhesion: A photosensitive resin composition was applied onto a silicon wafer with a copper plating formed on the surface using a spin coater, and then pre-baked at 120 ° C. for 3 minutes on a hot plate, and the film thickness was about 10 μm. A coating film was obtained. The obtained coating film was heated in an oven at 320 ° C. for 30 minutes while maintaining the oxygen concentration at 1000 ppm or less to obtain a cured film of the photosensitive resin composition. Next, 100 patterns of 1 mm × 1 mm were created using a cutter. Next, cellotape (registered trademark) having a peel strength of 3.0 mN / 10 mm was well pasted with an eraser on the surface of the pattern, and then the cellotape (registered trademark) was peeled off vertically. Next, the number of peeled patterns was counted. In this evaluation, it was evaluated that the smaller the number of patterns peeled, the better the adhesion to copper.

Patterning property: The obtained photosensitive resin composition was applied onto an 8-inch silicon wafer using a spin coater, and then pre-baked at 120 ° C. for 3 minutes on a hot plate to give a resin film having a thickness of about 7.5 μm. Got. An i-line stepper (Nikon NSR-4425i manufactured by Nikon Co., Ltd.) was passed through a mask made by Toppan Printing Co., Ltd. (test chart No. 1: remaining pattern and blank pattern having a width of 0.88 to 50 μm are drawn). ) And changed the exposure amount. Next, a 2.38% tetramethylammonium hydroxide aqueous solution is used as a developing solution, and the developing time is adjusted so that the difference between the film thickness after pre-baking and the film thickness after developing is 1.0 μm, and paddle twice. The exposed portion was dissolved and removed by developing, and then rinsed with pure water for 10 seconds. Then, the presence or absence of residue generation was confirmed by observing the opening portion of the pattern formed in the resin film at a magnification of 200 times with an optical microscope, and evaluated according to the following criteria.
A: No residue is observed.
○: Residue was observed, but practically usable.
X: A residue is observed and it is difficult to withstand practical use.

Tensile modulus: Five test pieces having a thickness of 10 mm × 60 mm × 10 μm were prepared by curing the obtained photosensitive resin composition in a nitrogen atmosphere at 300 ° C. for 30 minutes. A tensile test (stretching speed: 5 mm / min) was performed in a 23 ° C. atmosphere using a tensile tester (Tensilon RTC-1210A) manufactured by Orientec Co., Ltd. for each of the five test pieces. The tensile modulus was calculated from the initial gradient of the obtained stress-strain curve, and the average value of five test pieces was taken as the tensile modulus. The unit is MPa.

Tensile elongation: Five test pieces having a thickness of 10 mm × 60 mm × 10 μm were prepared by curing the obtained photosensitive resin composition under a nitrogen atmosphere at 300 ° C. for 30 minutes. A tensile test (stretching speed: 5 mm / min) was performed in a 23 ° C. atmosphere using a tensile tester (Tensilon RTC-1210A) manufactured by Orientec Co., Ltd. for each of the five test pieces. Thereafter, the tensile elongation was calculated from the fractured distance and the initial distance using the following formulas, and the average value of the five test pieces was taken as the tensile elongation. The unit is%.
Formula: Tensile elongation (%) = (breaking distance−initial distance) / initial distance × 100

  Table 1 below shows examples and comparative examples.

  As shown in Table 1, the photosensitive resin compositions of Examples 1 to 11 can form a resin film having excellent adhesion with a copper substrate as compared with the photosensitive resin compositions of Comparative Examples 1 and 2. Met.

<Fabrication of semiconductor device>
Using the simulated element wafer having an aluminum circuit on the surface, each of the photosensitive resin compositions of Examples 1 to 11 was applied so as to have a final film thickness of 5 μm, and then subjected to pattern processing and cured. After that, each chip size is divided and mounted on a lead frame for 16-pin DIP (Dual Inline Package) using a conductive paste, and then sealed with an epoxy resin for semiconductor encapsulation (EME-6300H, manufactured by Sumitomo Bakelite Co., Ltd.) The semiconductor device was fabricated by molding. These semiconductor devices (semiconductor packages) were treated at 85 ° C. and 85% humidity for 168 hours, then immersed in a 260 ° C. solder bath for 10 seconds, and then subjected to a high-temperature, high-humidity pressure cooker treatment (125 ° C., 2. (3 atm, 100% relative humidity) was applied to check the open failure of the aluminum circuit. Corrosion or the like did not occur in the obtained semiconductor device. Therefore, it was confirmed that the semiconductor device provided with the resin film produced using the photosensitive resin compositions of Examples 1 to 11 can be used practically without any problem.

100 Electronic Device 30 Interlayer Insulating Film 32 Passivation Film 34 Top Layer Wiring 40 Rewiring Layers 42, 44 Insulating Layer 46 Rewiring 50 UBM Layer 52 Bump

Claims (8)

An alkali-soluble resin (A);
A photosensitive agent (B);
A carboximide compound (C) having a molecular structure having a dicarboximide structure represented by the following formula (a), and a photosensitive resin material comprising:
Wherein the photosensitive resin material, 300 ° C., for 30 minutes in conditions, in nitrogen atmosphere, the cured film obtained by curing, it der tensile elongation 20% or more at 23 ° C.,
The photosensitive resin material in which the said carboximide compound (C) contains at least 1 of the dicarboximide compound represented by a following formula (c) .

(In formula (a), R 1 and R 2 are each an organic group having 1 to 20 carbon atoms, and may be the same or different. R 1 and R 2 are bonded to each other to form a ring structure 1. Or two or more may be formed.)

It further includes an adhesion aid (E),
2. The photosensitive resin material according to claim 1, wherein the content of the adhesion assistant (E) is 0.1 part by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the alkali-soluble resin (A).   The photosensitive resin material of Claim 1 or 2 whose content of the said carboximide compound (C) is 0.1 to 30 weight part with respect to 100 weight part of the said alkali-soluble resin (A). .   The said alkali-soluble resin (A) contains the 1 type (s) or 2 or more types selected from the group which consists of a polyimide and its precursor, polybenzoxazole and its precursor, a phenol resin, and a polyhydroxy styrene resin. 3. The photosensitive resin material according to 3.   The photosensitive resin material as described in any one of Claims 1 thru | or 4 which contains a ring structure in the said molecular structure of the said carboximide compound (C). The photosensitive resin material as described in any one of Claims 1 thru | or 5 which further contains a crosslinking agent (D). The photosensitive resin material as described in any one of Claims 1 thru | or 6 which further contains surfactant (F). The photosensitive resin material as described in any one of Claims 1 thru | or 7 which is a material for forming the permanent film used as an interlayer film, a surface protective film, or a dam material.

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