JP2019158949A - Photosensitive resin composition and electronic device - Google Patents

Abstract

To provide a photosensitive resin composition achieving patterning property, a good pattern profile and reduced tackiness after prebaking.SOLUTION: The photosensitive resin composition of the present invention is a photosensitive resin composition for forming a film, which comprises a thermosetting resin, a curing agent and a photosensitive agent. The thermosetting resin comprises a solid epoxy resin that is solid at 25°C and a liquid epoxy resin that is liquid at 25°C. The curing agent comprises a phenolic curing agent. A ratio Y/X, where X (mass%) represents the content of the solid epoxy resin and Y (mass%) represents the content of the liquid epoxy resin with respect to the whole nonvolatile component of the photosensitive resin composition, is 0.01 or more and 0.60 or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a photosensitive resin composition and an electronic device.

  Until now, various developments have been made in photosensitive resin compositions. As this type of technology, for example, the technology described in Patent Document 1 is known. Patent Document 1 describes a photosensitive resin composition containing, as a thermosetting component, a solid epoxy resin that is solid at 40 ° C. or a semi-solid epoxy resin that is liquid at 40 ° C. (Patent Document 1). Claim 6, Table 1).

JP 2017-215565 A

  However, as a result of investigation by the present inventors, it has been found that the photosensitive resin composition described in Patent Document 1 has room for improvement in terms of patternability, pattern shape, and post-baking tackiness.

  The present inventor further examined that, in the photosensitive resin composition containing the phenolic curing agent, by appropriately selecting the content ratio of the solid epoxy resin and the liquid epoxy resin, the patterning property, the pattern shape, and the pre-baking It has been found that the post-tackiness can be improved, and the present invention has been completed.

According to the present invention,
A photosensitive resin composition for film formation comprising a thermosetting resin, a curing agent, and a photosensitive agent,
The thermosetting resin includes a solid epoxy resin that is solid at 25 ° C. and a liquid epoxy resin that is liquid at 25 ° C.,
The curing agent includes a phenolic curing agent,
When the content of the solid epoxy resin is X (mass%) and the content of the liquid epoxy resin is Y (mass%) with respect to the entire nonvolatile components of the photosensitive resin composition,
A photosensitive resin composition satisfying Y / X of 0.01 or more and 0.60 or less is provided.

  Moreover, according to this invention, an electronic device provided with the hardened | cured material of the said photosensitive resin composition is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the photosensitive resin composition which can implement | achieve patternability, a pattern shape, and a tack property after prebaking, and an electronic device using the same are provided.

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

Hereinafter, the outline | summary of the photosensitive resin composition which concerns on embodiment of this invention is demonstrated.
The photosensitive resin composition of this embodiment contains a thermosetting resin, a curing agent, and a photosensitive agent. The thermosetting resin includes a solid epoxy resin that is solid at 25 ° C. and a liquid epoxy resin that is liquid at 25 ° C., and the curing agent may include a phenol-based curing agent. And such photosensitive resin composition makes content of the said solid epoxy resin X (mass%) with respect to the whole non-volatile component of the said photosensitive resin composition, and makes content of the said liquid epoxy resin Y (mass). %), Y / X can satisfy 0.01 or more and 0.60 or less.
The photosensitive resin composition of this embodiment can be used as a photosensitive resin composition for film formation.

  According to the photosensitive resin composition of the present embodiment, a cured film having an opening pattern excellent in patternability and pattern shape can be realized. In the resin film made of the photosensitive resin composition of the present embodiment, tackiness in pre-baked (PAB) can be reduced. Such a cured film of the photosensitive resin composition can be suitably used for various electronic devices. Therefore, in the electronic device provided with the cured product of the photosensitive resin composition of the present embodiment, improvement in manufacturing stability and reliability is expected.

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

<Thermosetting resin>
The photosensitive resin composition of this embodiment can contain an epoxy resin.

  The epoxy resin can include a polyfunctional epoxy resin having two or more epoxy groups in the molecule. Thereby, the film | membrane physical property and workability in the resin film of the photosensitive resin composition can be improved.

  Examples of the polyfunctional epoxy resin include phenol novolac type epoxy resin, cresol novolak type epoxy resin, cresol naphthol type epoxy resin, biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, phenoxy resin, naphthalene skeleton type epoxy resin, and bisphenol A. Type 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. And the like. These may be used alone or in combination of two or more. Among these, phenol novolac and cresol novolac type epoxy resins are excellent in heat resistance and low CTE.

  The said photosensitive resin composition can contain the solid epoxy resin which has a 2 or more epoxy group in a molecule | numerator as a polyfunctional epoxy resin. As said solid epoxy resin, it has 2 or more epoxy groups, and what is solid in 25 degreeC can be used. Thereby, the film | membrane physical property and workability in the resin film of the photosensitive resin composition can be improved.

  The said photosensitive resin composition can contain the liquid epoxy resin which has a 2 or more epoxy group in a molecule | numerator as a polyfunctional epoxy resin. The liquid epoxy resin functions as a filming agent and can improve brittleness of the cured film of the photosensitive resin composition.

  As the liquid epoxy resin, an epoxy compound which has two or more epoxy groups and is liquid at 25 ° C. can be used. The viscosity of the liquid epoxy resin at 25 ° C. is, for example, 1 mPa · s to 8000 mPa · s, preferably 5 mPa · s to 1500 mPa · s, and more preferably 10 mPa · s to 1400 mPa · s. .

  Examples of the liquid epoxy resin may include one or more selected from the group consisting of bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, alkyl diglycidyl ether, and alicyclic epoxy. These may be used alone or in combination of two or more. Among these, alkyl diglycidyl ether can be used from the viewpoint of reducing cracks after development.

  The epoxy equivalent of the liquid epoxy resin is, for example, 100 g / eq or more and 200 g / eq or less, preferably 105 g / eq or more and 180 g / eq or less, more preferably 110 g / eq or more and 170 g / eq or less. . Thereby, the brittleness of a cured film can be improved.

  The lower limit of the content of the liquid epoxy resin is, for example, 5% by mass or more, preferably 10% by mass or more, more preferably 15% by mass or more, with respect to the entire nonvolatile components of the photosensitive resin composition. It is. Thereby, the brittleness of the finally obtained cured film can be improved. On the other hand, the upper limit of the content of the liquid epoxy resin is, for example, 40% by mass or less, preferably 35% by mass or less, and more preferably 30% by mass with respect to the entire nonvolatile components of the photosensitive resin composition. It is as follows. Thereby, the balance of the film | membrane characteristic of a cured film can be aimed at.

  The lower limit of the content of the epoxy resin is, for example, 40% by mass or more, preferably 45% by mass or more, and more preferably 50% by mass or more, with respect to the entire nonvolatile components of the photosensitive resin composition. is there. Thereby, the heat resistance and mechanical strength of the finally obtained cured film can be improved. On the other hand, the upper limit of the content of the epoxy resin is, for example, 80% by mass or less, preferably 75% by mass or less, and more preferably 70% by mass or less, with respect to the entire nonvolatile components of the photosensitive resin composition. It is. Thereby, patterning property can be improved.

  In this embodiment, the whole non-volatile component of the photosensitive resin composition refers to the non-volatile component in the photosensitive resin composition and refers to the remainder excluding volatile components such as water and solvent.

  Examples of thermosetting resins other than the epoxy resins described above include, for example, polyimide resins, bismaleimide resins, urea (urea) resins, melamine resins, polyurethane resins, cyanate ester resins, silicone resins, oxetane resins (oxetane compounds), (Meth) acrylate resin, unsaturated polyester resin, diallyl phthalate resin, benzoxazine resin and the like.

<Curing agent>
The photosensitive resin composition of this embodiment can contain a phenol type hardening | curing agent as a hardening | curing agent. Thereby, the film | membrane physical property, workability, and pattern shape in the resin film of the photosensitive resin composition can be improved. The phenolic curing agent is not particularly limited as long as it promotes the polymerization / crosslinking reaction of the thermosetting resin (epoxy resin) described above.

  The said phenol type hardening | curing agent can contain the hardening | curing agent which has a phenolic hydroxyl group, and specifically, it is preferable that the polyfunctional phenol resin which has a 2 or more phenolic hydroxyl group in a molecule | numerator is included. Thereby, it is thought that the thermal expansion of a cured film can be made still smaller and it can contribute to the reliability improvement of an electronic device. The polyfunctional phenol resin can be appropriately selected from known ones. For example, a novolac type phenol resin, a resol type phenol resin, a trisphenylmethane type phenol resin, and an arylalkylene type phenol resin can be used. From the viewpoint of good development characteristics, a novolac type phenol resin can be used. The weight average molecular weight of the phenol resin is preferably 200 to 20,000, more preferably 300 to 15,000, still more preferably 350 to 13,000 (hereinafter, “to” is an upper limit unless otherwise specified). And the lower limit is included).

  Content of the said hardening | curing agent is 10-60 mass% with respect to the whole non-volatile component of the photosensitive resin composition, for example, Preferably it is 20-50 mass%, More preferably, it is 20-45 mass%. By setting it as this range, the heat resistance and strength of the cured product are improved.

  In this embodiment, the content of the solid epoxy resin is X (mass%) and the content of the liquid epoxy resin is Y (mass%) with respect to the entire nonvolatile components (100 mass%) of the photosensitive resin composition, and phenol. Let the content of a system hardening | curing agent be Z (mass%).

  In the present embodiment, the lower limit value of Y / X is, for example, 0.01 or more, preferably 0.15 or more, and more preferably 0.25 or more. Thereby, patterning property and pattern shape can be improved. The detailed mechanism is not clear, but by adding a liquid epoxy resin with good reactivity, the sensitivity can be improved and the patterning property can be improved, and after exposure by reducing the liquid epoxy resin with a flexible structure It is considered that the developer resistance of the resin in the exposed area that has reacted upon heating can be increased. On the other hand, the upper limit of Y / X is, for example, 0.60 or less, preferably 0.55 or less, and more preferably 0.50 or less. Thereby, the post-PAB tackiness can be improved. Although the detailed mechanism is not clear, it is considered that a decrease in tackiness due to stickiness derived from the liquid epoxy resin can be suppressed by adjusting the amount of the liquid epoxy resin.

  In the present embodiment, the lower limit value of Z / (X + Y) is, for example, 0.1 or more, preferably 0.15 or more, and more preferably 0.25 or more. Thereby, a pattern shape can be improved. Although the detailed mechanism is not clear, by making the addition amount of the epoxy resin with high reactivity at the time of PEB an appropriate amount, the reaction of the epoxy resin proceeds at a high density and the shrinkage increases, resulting in a decrease in pattern shape. It can be suppressed. On the other hand, the upper limit of Z / (X + Y) is, for example, 1.5 or less, preferably 1.3 or less, and more preferably 1.2 or less. Thereby, patterning property can be improved. Although the detailed mechanism is not clear, by making the addition amount of phenol resin appropriate, it is possible to prevent the progress of the reaction from being suppressed due to the excessive presence of phenol resin that does not react alone, so that the patterning property is improved. It can be improved.

  In the present embodiment, the lower limit value of Y / (X + Z) is, for example, 0.01 or more, preferably 0.15 or more, and more preferably 0.25 or more. Thereby, patterning property can be improved. Although the detailed mechanism is not clear, it is considered that the addition of a liquid epoxy resin having good reactivity can improve the sensitivity and enhance the patternability. On the other hand, the upper limit of Y / (X + Z) is, for example, 1.2 or less, preferably 0.55 or less, and more preferably 0.50 or less. Thereby, the post-PAB tackiness can be improved. Although the detailed mechanism is not clear, it is considered that a decrease in tackiness due to stickiness derived from the liquid epoxy resin can be suppressed by adjusting the liquid epoxy resin to an appropriate amount. In addition, by making it within the range of the above upper limit value and lower limit value, it is possible to realize a photosensitive resin composition having excellent characteristics in the balance of patternability, pattern shape, and tackiness after PAB, and development. It is considered that the remaining scum can be suppressed by increasing the amount of liquid epoxy resin having good solubility in the liquid.

<Photosensitive agent>
The photosensitive resin composition of this embodiment can contain a photosensitive agent. Thereby, the workability at the time of patterning, such as sensitivity and resolution, can be improved.
As the photosensitive agent, a photoacid generator can be used. As said photoacid generator, the photoacid generator which generate | occur | produces an acid by irradiation of actinic rays, such as an ultraviolet-ray, is contained. Examples of photoacid generators include onium salt compounds, such as diazonium salts, iodonium salts such as diaryliodonium salts, sulfonium salts such as triarylsulfonium salts, triarylbililium salts, benzylpyridinium thiocyanate, dialkylphenacyl. Examples thereof include cationic photopolymerization initiators such as sulfonium salts and dialkylhydroxyphenylphosphonium salts. Moreover, the photosensitive diazoquinone compound can also be mentioned. The photosensitive diazoquinone compound is particularly preferably used when the photosensitive resin composition is made positive. The photosensitive agent is preferably one that does not generate hydrogen fluoride due to decomposition, such as a methide salt type or a borate salt type, because the photosensitive composition contacts the metal.

  The lower limit of the content of the photosensitive agent is, for example, 0.3% by mass or more, preferably 0.5% by mass or more, and more preferably 0% with respect to the entire nonvolatile components of the photosensitive resin composition. 0.7% by mass or more. Thereby, patterning property can be improved in the photosensitive resin composition. On the other hand, the upper limit of the content of the photosensitive agent is, for example, 5% by mass or less, preferably 4.5% by mass or less, more preferably, based on the entire nonvolatile components of the photosensitive resin composition. 4% by mass or less. Thereby, the long-term storage property before hardening of the photosensitive resin composition can be improved.

<Surfactant>
The photosensitive resin composition of the present embodiment can contain a surfactant. By including the surfactant, wettability during coating can be improved, and a uniform resin film and cured film can be obtained. Further, it can be expected to prevent residues and patterns from rising during development. Examples of the surfactant include a fluorine-based surfactant, a silicone-based surfactant, an alkyl-based surfactant, and an acrylic surfactant.

  The surfactant preferably includes a surfactant containing at least one of a fluorine atom and a silicon atom. As a result, a uniform resin film can be obtained (improvement of applicability), and in addition to improvement of developability, it also contributes to improvement of adhesive strength. As such a surfactant, for example, a nonionic surfactant containing at least one of a fluorine atom and a silicon atom is preferable. As a commercial item which can be used as a surfactant, for example, F-251, F-253, F-281, F-430, F-477, F-551 of "Megafac" 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. Surfactant having an oligomer structure containing fluorine, fluorine-containing nonionic surfactants such as Footage 250 and Footgent 251 manufactured by Neos Co., Ltd., SILFOAM (registered trademark) series manufactured by Wacker Chemie (for example, SD) 100 TS, SD 670, SD 850, SD 860, SD 882) and the like.

  In addition to the above components, the photosensitive resin composition of the present embodiment can contain other additives as necessary. Examples of other additives include antioxidants, fillers such as silica, sensitizers, filming agents, adhesion assistants, and the like.

<Adhesion aid>
The photosensitive resin composition of this embodiment can contain an adhesion assistant. Thereby, the adhesiveness of a cured film can be improved further.

The adhesion aid is not particularly limited, and for example, a silane coupling agent such as amino silane, epoxy silane, acrylic silane, mercapto silane, vinyl silane, ureido silane, or sulfide silane can be used. A silane coupling agent may be used individually by 1 type, and may use 2 or more types together. Among these, it is more preferable to use epoxysilane (that is, a compound containing both an epoxy moiety and a group that generates a silanol group by hydrolysis) in one molecule.
Examples of the aminosilane include bis (2-hydroxyethyl) -3-aminopropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, and γ-aminopropyl. Methyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, N -Β (aminoethyl) γ-aminopropylmethyldiethoxysilane, N-phenyl-γ-amino-propyltrimethoxysilane and the like can be mentioned. Examples of the epoxy silane include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and γ-glycidylpropyltrimethoxysilane. Etc. Examples of the acrylic silane include γ- (methacryloxypropyl) trimethoxysilane, γ- (methacryloxypropyl) methyldimethoxysilane, and γ- (methacryloxypropyl) methyldiethoxysilane. Examples of mercaptosilane include 3-mercaptopropyltrimethoxysilane. Examples of vinyl silane include vinyl tris (β-methoxyethoxy) silane, vinyl triethoxy silane, and vinyl trimethoxy silane. Examples of ureidosilane include 3-ureidopropyltriethoxysilane. Examples of the sulfide silane include bis (3- (triethoxysilyl) propyl) disulfide, bis (3- (triethoxysilyl) propyl) tetrasulfide, and the like.

  The content of the adhesion assistant is, for example, preferably 0.5 to 10% by mass, more preferably 1 to 8% by mass, based on the total amount of nonvolatile components of the photosensitive resin composition.

  The photosensitive resin composition of the present embodiment may be in the form of a varnish or a film.

  The preparation method of the photosensitive resin composition of this embodiment is not specifically limited, Generally it can manufacture by a well-known method. For example, a varnish-like photosensitive resin composition (resin varnish) can be obtained by mixing and uniformly mixing the above-described components (raw materials) and a solvent.

<Solvent>
The photosensitive resin composition of this embodiment can contain a solvent. An organic solvent can be included as a solvent.
The organic solvent can be used without particular limitation as long as it can dissolve each component of the photosensitive resin composition and does not chemically react with each constituent component. 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 monobutyl ether acetate, benzyl alcohol, propylene carbonate, ethylene Examples thereof include glycol diacetate, propylene glycol diacetate, propylene glycol monomethyl ether acetate, and γ-butyrolactone. These can be appropriately selected depending on the desired film thickness. These may be used alone or in combination of two or more.

  It is preferable that the said solvent is used so that the density | concentration of the non-volatile component whole quantity in the photosensitive resin composition may be 30-75 mass%, for example. By setting it as this range, each component can fully be dissolved and good applicability | paintability can be ensured.

  On the other hand, the film-like photosensitive resin composition (photosensitive resin film) is, for example, a coating film (resin film) obtained by applying a varnish-like photosensitive resin composition on a carrier substrate. It can be obtained by performing a solvent removal treatment. The photosensitive resin film may have a solvent content of 10% by weight or less with respect to the entire photosensitive resin composition. For example, the solvent removal treatment can be performed under conditions of 80 ° C. to 150 ° C. and 1 minute to 30 minutes. Thereby, it becomes possible to remove the solvent sufficiently while suppressing the curing of the photosensitive resin composition.

  The step of forming the resin film of the photosensitive resin composition on the carrier substrate is, for example, preparing a resin varnish by dissolving and dispersing the photosensitive resin composition in a solvent or the like, and using various coater devices Examples thereof include a method of drying the varnish after coating the carrier substrate, a method of spraying the resin varnish onto the carrier substrate using a spray device, and then drying the resin varnish. Among these, it is preferable to apply a resin varnish to a carrier substrate using various coaters such as a spin coater, a comma coater, and a die coater, and then dry the resin varnish. Thereby, the photosensitive resin film with a carrier base material which has no void and has a uniform thickness can be efficiently produced.

  The above-mentioned photosensitive resin film with a carrier substrate may be a rollable roll or a rectangular sheet. The surface of the photosensitive resin film with a carrier substrate may be exposed or covered with a protective film (cover film), for example. As the protective film, a film having a known protective function can be used. For example, a PET film may be used.

  In the present embodiment, as the carrier substrate, for example, a polymer film or a metal foil can be used. The polymer film is not particularly limited. For example, polyolefin such as polyethylene and polypropylene, polyester such as polyethylene terephthalate and polybutylene terephthalate, release paper such as polycarbonate and silicone sheet, heat resistance such as fluorine resin and polyimide resin. A thermoplastic resin sheet having The metal foil is not particularly limited. For example, copper and / or a copper-based alloy, aluminum and / or an aluminum-based alloy, iron and / or an iron-based alloy, silver and / or a silver-based alloy, gold and a gold-based alloy. Zinc and zinc-based alloys, nickel and nickel-based alloys, tin and tin-based alloys, and the like. Among these, a sheet made of polyethylene terephthalate is most preferable because it is inexpensive and easy to adjust the peel strength. Thereby, it becomes easy to peel a carrier base material with moderate intensity | strength from the photosensitive resin film with a carrier base material.

  The film thickness of the photosensitive resin film can be designed according to the final film thickness of the cured film. The lower limit of the film thickness of the photosensitive resin film is, for example, 40 μm or more, preferably 50 μm or more, and more preferably 60 μm or more. Thereby, a thick photosensitive resin film can be realized. The embedding property of an electronic member such as a semiconductor chip of a photosensitive resin film can be improved. Moreover, the mechanical strength of the photosensitive resin film can be improved. On the other hand, the upper limit value of the film thickness of the photosensitive resin film is not particularly limited, but may be, for example, 300 μm or less, 250 μm or less, or 200 μm or less. Thereby, thinning of an electronic device provided with the cured film of the photosensitive resin film is realizable.

<Hardened film, formation method thereof>
The method for obtaining the cured film of the photosensitive resin composition of the present embodiment is not particularly limited. For example, the following steps:
A step of providing the photosensitive resin composition on the substrate (step 1);
A step of drying the photosensitive resin composition by heating to obtain a photosensitive resin film (step 2);
A step of exposing the photosensitive resin film with actinic rays (step 3);
Developing the exposed photosensitive resin film to obtain a patterned resin film (step 4); and
Heating the patterned resin film to obtain a cured film (step 5);
Thereby, the cured film of the photosensitive resin composition of this embodiment can be obtained.

  In step 1, the substrate is not particularly limited, and examples thereof include a silicon wafer, a ceramic substrate, an aluminum substrate, a SiC wafer, and a GaN wafer. The substrate includes, in addition to an 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. In order to improve adhesion, the substrate surface may be treated with an adhesion aid such as a silane coupling agent. The method for providing the photosensitive resin composition on the substrate can be performed by spin coating, spray coating, dipping, printing, roll coating, ink jet method or the like.

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

In step 3, as the actinic ray for exposure, for example, X-rays, electron beams, ultraviolet rays, visible rays and the like can be used. In terms of wavelength, an actinic ray of 200 to 500 nm is preferable. From the viewpoint of pattern resolution and handleability, the light source is preferably a g-line, h-line or i-line of a mercury lamp. Two or more light beams may be mixed and used. As the exposure apparatus, a contact aligner, mirror projection or stepper is preferable.
After the exposure, the photosensitive resin film is heated again (heated after exposure). The post-exposure heating temperature and time are, for example, about 60 to 140 ° C. and about 10 to 300 seconds.

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

  The developer that can be used is not particularly limited, but in the present embodiment, a developer containing an organic solvent as a main component (a developer having 95% by mass or more of the component being an organic solvent) is preferable. Specific examples include ketone solvents such as cyclopentanone, ester solvents such as propylene glycol monomethyl ether acetate (PGMEA) and butyl acetate, ether solvents such as propylene glycol monomethyl ether, and the like. Moreover, as a developing solution, you may use the organic solvent developing solution which consists only of organic solvents.

  After the development step, the developer may not be washed with a rinse solution, but may be washed with a rinse solution as necessary to remove the developer. Examples of the rinsing liquid include distilled water, methanol, ethanol, isopropanol, and propylene glycol monomethyl ether. You may use these individually or in combination of 2 or more types.

  In step 5, a cured film can be obtained by heating the patterned resin film. In this embodiment, the heating temperature is preferably 150 to 300 ° C, and more preferably 170 to 200 ° C. By setting it as this temperature range, the speed | rate of a crosslinking reaction and the uniform hardening in the whole film | membrane can be made compatible. Although heating time is not specifically limited, For example, it exists in the range of 15 to 300 minutes. This heat treatment can be performed by a hot plate, an oven, a temperature rising oven in which a temperature program can be set, or the like. The atmospheric gas for performing the heat treatment may be air or an inert gas such as nitrogen or argon. Moreover, you may heat under reduced pressure.

The photosensitive resin composition of the present embodiment is used as, for example, a permanent film, a protective film, an insulating film, a rewiring material or the like in an electrical / electronic device (electronic device).
In an electronic device including a cured product of the photosensitive resin composition of the present embodiment, improvement in manufacturing stability and reliability is expected.
Here, “electrical / electronic device” means a semiconductor chip, a semiconductor element, a printed wiring board, an electric circuit, a display device such as a television receiver or a monitor, an information communication terminal, a light emitting diode, a physical battery, a chemical battery, etc. This refers to devices, devices, final products, and other equipment related to electricity that apply engineering technology.

As one specific example of the use of the photosensitive resin composition of the present embodiment, a through electrode substrate can be mentioned. Hereinafter, an electronic device including the through electrode substrate will be described with reference to FIG.
FIG. 1A is a cross-sectional view showing the configuration of the electronic device of this embodiment. FIG. 1B is an enlarged view of a part of the electronic device shown in FIG.

As shown in FIG. 1A, the electronic device 100 according to the present embodiment includes a through electrode substrate 200. The through electrode substrate 200 includes an organic insulating layer (photosensitive resin layer 220), a plurality of through electrodes (vias 242) penetrating from the upper surface to the lower surface of the organic insulating layer, and a semiconductor chip 210 embedded in the organic insulating layer. And a lower wiring layer 252 provided on the lower surface of the organic insulating layer, and an upper wiring layer 250 provided on the upper surface of the organic insulating layer.
The photosensitive resin layer 220 and the upper wiring layer 250 can be formed of a cured film (cured product) of the photosensitive resin composition of the present embodiment. For the formation of the photosensitive resin layer 220, a film-like photosensitive resin composition can be used. The upper wiring layer 250 can be formed using a varnish-like (liquid at room temperature of 25 ° C.) photosensitive resin composition.

  In the electronic device 100 of this embodiment, a package structure such as a package-on-package is configured by the above-described through electrode substrate 200 without using a thick film package substrate having a core layer or a build-up layer. For this reason, in the electronic device 100, the overall height of the package structure can be reduced.

  In addition, as shown in FIG. 1A, the electronic device 100 according to this embodiment can have a package-on-package structure in which a semiconductor package 300 is mounted on a through electrode substrate 200. For example, the electronic device 100 of this embodiment can further include a semiconductor package 300 having a known package structure mounted on the upper wiring layer 250 of the through electrode substrate 200. Thereby, the multifunctionalization of the electronic device 100 can be realized. In addition, the mounting density of the electronic device 100 can be increased.

  In the present embodiment, for example, as shown in FIG. 1A, the semiconductor package 300 has a semiconductor chip 310 mounted on a substrate 320, and the substrate 320 and the semiconductor chip 310 are bonded to each other via bonding wires 330. You may have the structure to do. In the semiconductor package 300, a plurality of semiconductor chips 310 may be provided, and a plurality of semiconductor chips 310 may be arranged in the planar direction or the stacking direction. Further, the semiconductor chip 310 and the bonding wire 330 may be sealed with a sealing material layer 340. The sealing material layer 340 can be formed, for example, by curing a known sealing resin composition. In addition, solder bumps 360 may be formed on the substrate 320 of the semiconductor package 300 as external terminals. The semiconductor package 300 can be bump-connected to the through electrode substrate 200 via the solder bump 360.

  In addition, the electronic device 100 of the present embodiment can include solder bumps 260 provided on the lower surface of the lower wiring layer 252 of the through electrode substrate 200. As a result, the solder bump 260 functions as an external terminal, thereby enabling external connection with other electronic components.

  Such an electronic device 100 can further include, for example, a mother board that is bump-connected to the lower wiring layer 252 of the through electrode substrate 200 via the solder bumps 260. Thereby, the mechanical strength of the electronic device 100 can be increased, and further multifunctionalization can be realized. At this time, in the through electrode substrate 200, the side surfaces and upper and lower surfaces thereof may be sealed together with the semiconductor package 300 with a sealing material layer formed by curing a known sealing resin composition. Thereby, the connection reliability and mechanical strength of the electronic device 100 can be improved.

  The through electrode substrate 200 included in the electronic device 100 of the present embodiment has an organic layer in addition to the structure in which the upper wiring layer 250 and the lower wiring layer 252 are formed on the upper and lower surfaces of the organic insulating layer (photosensitive resin layer 220), respectively. Since the semiconductor chip 210 and the through electrode (via 242) for electrically connecting the wiring layers are embedded in the insulating layer, the mechanical strength is excellent as compared with a structure without these. be able to.

  Moreover, in embodiment, the organic insulating layer in the said penetration electrode substrate 200 can be comprised with the hardened | cured material of the above-mentioned photosensitive resin composition. Accordingly, since a method of opening by a photoresist method can be adopted, the opening diameter, in other words, the via diameter of the via 242 can be made smaller than in the method of opening by laser irradiation. The integration density of the semiconductor chips 210 and the vias 242 can be increased in the plane of the through electrode substrate 200. Moreover, the mechanical strength of the through electrode substrate 200 can be increased by curing the photosensitive resin composition.

  Moreover, the lower limit of the film thickness of the organic insulating layer (photosensitive resin layer 220) in the through electrode substrate 200 of the present embodiment may be, for example, 40 μm or more, more preferably 50 μm or more, and still more preferably. It is good also as 60 micrometers or more. Thereby, the mechanical strength of the through electrode substrate 200 can be improved. In addition, the embedding property of the semiconductor chip 210 can be improved. On the other hand, the upper limit value of the film thickness of the organic insulating layer may be, for example, 300 μm or less, more preferably 250 μm or less, and even more preferably 200 μm or less. Thereby, the height of the electronic device 100 can be reduced.

  The through electrode (via 242) is, for example, a conductive frustum made of one or more metals selected from the group consisting of copper, gold, silver, nickel, and the like. Specifically, the conductive frustum Or a conductive polygonal frustum, more specifically, a copper frustum (copper pillar).

  In the electronic device 100 of the present embodiment, as shown in FIG. 1A, the wirings constituting the lower wiring layer 252 may be formed to the outside of the semiconductor chip 210 in a cross-sectional view. As a result, the inter-electrode pitch width of the structure in which the plurality of semiconductor chips 210 are mounted at high density can be expanded to the optimum pitch width for connection to the solder bumps 260. That is, the mounting density of the semiconductor chip 210 can be increased.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

<Preparation of photosensitive resin composition>
The raw materials of each component blended according to Table 1 were dissolved in propylene glycol monomethyl ether acetate (PGMEA) to obtain a mixed solution. Thereafter, the mixed solution was filtered through a 0.2 μm polyethylene filter to obtain a photosensitive resin composition having a solid content of 50% by mass.
The detail of the raw material of each component in Table 1 is as follows.

(Thermosetting resin)
Solid epoxy resin Solid epoxy resin (A-1): phenol novolac type epoxy resin (EPPN201, manufactured by Nippon Kayaku Co., Ltd.)
Solid epoxy resin (A-2): Cresol novolac type epoxy resin (EOCN-1020, manufactured by Nippon Kayaku Co., Ltd.)
Solid epoxy resin (A-3): TPM type epoxy resin (jer-1032H60, manufactured by Mitsubishi Chemical Corporation)
Liquid epoxy resin Liquid epoxy resin (B-1): Bisphenol A type epoxy resin (LX-01, manufactured by Osaka Soda Co., Ltd.)
Liquid epoxy resin (B-2): Mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin (EXA-835LV, manufactured by DIC Corporation)
Liquid epoxy resin (B-3): 1,6-hexanediol diglycidyl ether (YED216D, manufactured by Mitsubishi Chemical Corporation)
-Phenol resin Phenol resin (C-1): Phenol novolac resin (PR51470, manufactured by Sumitomo Bakelite Co., Ltd.)
Phenol resin (C-2): Cresol novolak resin (KA1165, manufactured by DIC Corporation)
Phenol resin (C-3): Phenol aralkyl resin (MEHS-7000-4S, manufactured by Meiwa Kasei Co., Ltd.)
Photoacid generator Photoacid generator (D-1): Triarylsulfonium salt (CPI-310B, manufactured by San Apro)
Silane coupling agent Silane coupling agent (E-1): γ-trimethoxypropyltrimethoxysilane (KBM-403E, manufactured by Shin-Etsu Chemical Co., Ltd.)
Surfactant Surfactant (F-1): Fluorine-based surface conditioner (F-563, manufactured by DIC)

  The obtained photosensitive resin composition was evaluated based on the following evaluation items. The evaluation results are shown in Table 1.

<Evaluation of patterning>
The obtained photosensitive resin composition was applied onto the wafer by spin coating so that the film thickness after drying was 10 μm, and dried at 120 ° C. for 5 minutes to obtain a photosensitive resin film. Subsequently, the photosensitive resin film was subjected to pattern exposure of a round via having a diameter of 10 μm at 250 mJ / cm ² with an i-line stepper. Thereafter, post-exposure heat treatment (PEB) was performed at 100 ° C. for 5 minutes on a hot plate. Subsequently, the unexposed portion was dissolved and removed by spray development with PGMEA (propylene glycol monomethyl ether acetate) for 30 seconds. Subsequently, a cured product of the photosensitive resin composition in which a negative pattern was formed was obtained by curing at 200 ° C. for 90 minutes. Observe the resulting via pattern from the top, ◎ if it is open, ○ if it is open but there is a residue on the bottom of the via, ○, not open to the bottom of the via Or, the one where the exposed part was also dissolved was marked with x.

<Evaluation of pattern shape>
The obtained photosensitive resin composition was applied onto the wafer by spin coating so that the film thickness after drying was 10 μm, and dried at 120 ° C. for 5 minutes to obtain a photosensitive resin film. Subsequently, the photosensitive resin film was subjected to pattern exposure of a line having a width of 10 μm at 250 mJ / cm ² with an i-line stepper. Thereafter, post-exposure heat treatment (PEB) was performed at 100 ° C. for 5 minutes on a hot plate. Subsequently, the unexposed portion was dissolved and removed by spray development with PGMEA (propylene glycol monomethyl ether acetate) for 30 seconds. Subsequently, a cured product of the photosensitive resin composition in which a negative pattern was formed was obtained by curing at 200 ° C. for 90 minutes. Observe the cross-section of the obtained line pattern with SEM, ○ if the taper angle of the via is 70 to 90 degrees and no undercut, ○ if the taper angle of the via is not 70 to 90 degrees or there is an undercut × It was. In Table 1, “-” indicates that the exposed portion was dissolved and it was difficult to determine the pattern shape.

<Evaluation of tackiness after pre-baking (PAB)>
The obtained photosensitive resin composition was applied onto the wafer by spin coating so that the film thickness after drying was 10 μm, and dried at 120 ° C. for 5 minutes to obtain a photosensitive resin film. When the surface of the resin film is touched with a finger, x indicates that a part of the resin is transferred to the finger, ○ indicates that the appearance of the resin surface changes without being transferred, and there is no change in the appearance of the resin surface without transfer The thing was ◎.

  It turned out that the photosensitive resin composition of Examples 1-6 can implement | achieve the outstanding patternability, pattern shape, and prebaking tack property compared with Comparative Examples 1-4.

DESCRIPTION OF SYMBOLS 100 Electronic device 200 Penetration electrode substrate 210 Semiconductor chip 220 Photosensitive resin layer 242 Via 250 Upper wiring layer 252 Lower wiring layer 260 Solder bump 300 Semiconductor package 310 Semiconductor chip 320 Substrate 330 Bonding wire 340 Sealing material layer 360 Solder bump

Claims (11)

A photosensitive resin composition for film formation comprising a thermosetting resin, a curing agent, and a photosensitive agent,
The thermosetting resin includes a solid epoxy resin that is solid at 25 ° C. and a liquid epoxy resin that is liquid at 25 ° C.,
The curing agent includes a phenolic curing agent,
When the content of the solid epoxy resin is X (mass%) and the content of the liquid epoxy resin is Y (mass%) with respect to the entire nonvolatile components of the photosensitive resin composition,
A photosensitive resin composition satisfying Y / X of 0.01 or more and 0.60 or less. The photosensitive resin composition according to claim 1,
When the content of the phenol-based curing agent is Z (% by mass) relative to the entire nonvolatile components of the photosensitive resin composition,
A photosensitive resin composition satisfying Z / (X + Y) of 0.1 or more and 1.5 or less. The photosensitive resin composition according to claim 1 or 2,
When the content of the phenol-based curing agent is Z (% by mass) relative to the entire nonvolatile components of the photosensitive resin composition,
A photosensitive resin composition satisfying Y / (X + Z) of 0.01 or more and 1.2 or less. It is the photosensitive resin composition of any one of Claim 1 to 3, Comprising:
The photosensitive resin composition in which the said solid epoxy resin contains the solid epoxy resin which has a 2 or more epoxy group in a molecule | numerator. The photosensitive resin composition according to claim 4,
The photosensitive resin composition in which the said liquid epoxy resin contains the liquid epoxy resin which has a 2 or more epoxy group in a molecule | numerator. It is the photosensitive resin composition of any one of Claim 1 to 5, Comprising:
The photosensitive resin composition in which the said phenol type hardening | curing agent contains the polyfunctional phenol resin which has a 2 or more phenolic hydroxyl group in a molecule | numerator. It is the photosensitive resin composition of any one of Claim 1 to 6, Comprising:
A photosensitive resin composition containing a surfactant. It is the photosensitive resin composition of any one of Claim 1 to 7, Comprising:
The photosensitive resin composition in which the said photosensitive agent contains a photo-acid generator. It is the photosensitive resin composition of any one of Claim 1 to 8, Comprising:
A photosensitive resin composition comprising a silane coupling agent. It is the photosensitive resin composition of any one of Claim 1 to 9, Comprising:
A photosensitive resin composition in the form of a varnish or a film.   An electronic device provided with the hardened | cured material of the photosensitive resin composition of any one of Claim 1 to 10.

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