TW201843287A - Sealing film and sealed structure, and method for manufacturing sealing film and sealed structure - Google Patents

Abstract

Provided is a method for manufacturing a sealing film containing a heat curable resin, and an inorganic filler, the method comprising: the step for preparing a resin composition containing a resin having a reactive functional group equivalent of 250 g/mol or larger as the heat curable resin, and the inorganic filler; and the step for shaping the resin composition into a film.

Description

Sealing film, sealing structure, and manufacturing method thereof

The present invention relates to a sealing film, a sealing structure, and a method for manufacturing the same.

With the reduction in weight and thickness of electronic devices, miniaturization and reduction in thickness of electronic component devices (semiconductor devices, etc.) are progressing. A form that uses a semiconductor device that is almost the same size as a semiconductor element or a structure that mounts a semiconductor device on the semiconductor device (package-on-package) is booming, and miniaturization of electronic parts and devices is expected in the future. And thinning further progress.

If the miniaturization of the semiconductor element progresses and the number of terminals gradually increases, it becomes difficult to provide all external connection terminals (terminals for external connection) on the semiconductor element. For example, when external connection terminals are forcibly provided, the distance between the terminals becomes narrower, and the height of the terminals becomes lower, making it difficult to ensure connection reliability after the semiconductor device is constructed. Therefore, in order to reduce the size and thickness of electronic parts, many new construction methods have been proposed.

It has been proposed, for example, a mounting method and a semiconductor device manufactured by using the mounting method: a semiconductor device manufactured by singulating a semiconductor wafer can be rearranged at an appropriate interval, and then a solid or A liquid resin (resin for sealing) is used to seal a semiconductor element, and an external connection terminal is provided at a sealing portion which is a portion that seals the semiconductor element outside the semiconductor element (see, for example, Patent Document 1 below) ~ 3).

In the above-mentioned assembly method, the following steps are performed: for a sealed structure (sealed molded product) produced by sealing an electronic component, a line for disposing external connection terminals and an external connection terminal are formed. Further, in the above-mentioned assembly method, a plurality of electronic component devices (semiconductor devices, etc.) may be obtained by singulating the sealed structure body. The sealed structure body may be obtained by sealing a plurality of electronic components (semiconductor elements, etc.). of. At this time, the more electronic components to be relocated, the more electronic component devices can be produced in one step. Therefore, research into increasing the size of the sealed structure is being carried out. Currently, for example, since a semiconductor manufacturing apparatus is used to form a circuit, the sealed structure is formed into a wafer shape (fan-out type wafer-level package), and there is a tendency that the wafer shape becomes larger in diameter. Furthermore, in order to increase the size and enable the use of a printed wiring board manufacturing apparatus (fan-out panel-level package), the panelization of a sealed structure is being studied. This printed wiring board manufacturing apparatus is cheaper than a semiconductor manufacturing apparatus. [Prior Art Literature] (Patent Literature)

Patent Document 1: Japanese Patent Application Publication No. 2015-178635 Patent Document 2: Japanese Patent Application Publication No. 2014-131016 Patent Document 3: Japanese Patent Application Publication No. 2014-197670

[Problems to be Solved by the Invention] However, when sealing a sealed body using a sealing resin, the thermal expansion of the sealed body and a sealing portion (a hardened body of the sealing resin) for sealing the sealed body is caused by the thermal expansion Different rates can sometimes cause warping. In particular, in a thin semiconductor device without a package substrate such as a fan-out wafer-level package and a fan-out panel-level package, warpage is liable to occur.

Therefore, an object of the present invention is to provide a sealing film, a method for manufacturing the same, and a sealing structure obtained by using the sealing film, which can reduce warping of the sealing structure. [Technical means to solve the problem]

One aspect of the present invention relates to a method for producing a sealing film, the sealing film containing a thermosetting resin and an inorganic filler. This method includes the steps of preparing a resin composition containing a resin having a reactive functional group equivalent of more than 250 g / mol as a thermosetting resin, and an inorganic filler; and forming the resin composition into A step of forming a thin film. According to this method, it is possible to obtain a sealing film capable of reducing warpage of the sealing structure.

The glass transition temperature after the resin composition is cured may be 80 to 180 ° C. In this case, it is possible to obtain a sealing film capable of improving the reliability of the sealed structure.

The resin having a reactive functional group equivalent of more than 250 g / mol may include a resin having a reactive functional group equivalent of 300 to 410 g / mol. In this case, it is possible to obtain a sealing film which can further reduce the warpage of the sealing structure. Moreover, according to this method, it is easy to obtain a sealing film which has a sufficient glass transition temperature (Tg) after hardening and can improve the reliability of the sealing structure.

The resin composition may further contain a resin having a reactive functional group equivalent of 100 to 210 g / mol as a thermosetting resin. In this case, it is possible to obtain a sealing film which can further reduce the warpage of the sealing structure. In addition, according to this method, it is easy to obtain a sealing film which has a sufficient Tg after curing and can improve the reliability of the sealing structure.

The resin composition may further contain, as the thermosetting resin, a resin having a reactive functional group equivalent of more than 250 g / mol of the reactive functional group equivalent and having a reactive function of 1 / 2.9 to 1/2 times as a reactive functional group. Base equivalent resin. In this case, it is possible to obtain a sealing film which can further reduce the warpage of the sealing structure. In addition, according to this method, it is easy to obtain a sealing film which has a sufficient Tg after curing and can improve the reliability of the sealing structure.

The resin having a reactive functional group equivalent weight greater than 250 g / mol may include an epoxy resin. In this case, it is possible to obtain a sealing film which can further reduce the warpage of the sealing structure. In addition, according to this method, it is easy to obtain a sealing film which has a sufficient Tg after curing and can improve the reliability of the sealing structure.

The film thickness of the sealing film may be 20 to 250 μm. In this case, it is easy to suppress the variation in thickness in the surface during coating, and it is easy to obtain a certain drying property in the depth direction during coating.

One aspect of the present invention relates to a sealing film, which contains a thermosetting resin and an inorganic filler, and the thermosetting resin contains a resin having a reactive functional group equivalent weight greater than 250 g / mol. According to this sealing film, the warpage of the sealing structure can be reduced.

The glass transition temperature after the sealing film is cured may be 80 to 180 ° C. In this case, the reliability of the sealed structure can be improved.

The resin having a reactive functional group equivalent of more than 250 g / mol may include a resin having a reactive functional group equivalent of 300 to 410 g / mol. In this case, warpage of the sealing structure can be further reduced, and reliability of the sealing structure can be improved.

The thermosetting resin may further include a resin having a reactive functional group equivalent of 100 to 210 g / mol. In this case, warpage of the sealing structure can be further reduced, and reliability of the sealing structure can be improved.

The thermosetting resin may further include a resin having a reactive functional group equivalent of more than 250 g / mol of the reactive functional group equivalent, and a resin having a reactive functional group equivalent of 1 / 2.9 to 1/2 times. In this case, warpage of the sealing structure can be further reduced, and reliability of the sealing structure can be improved.

The resin having a reactive functional group equivalent weight greater than 250 g / mol may include an epoxy resin. In this case, warpage of the sealing structure can be further reduced, and reliability of the sealing structure can be improved.

The film thickness of the sealing film may be 20 to 250 μm. In this case, warpage of the sealing structure can be further reduced, and reliability of the sealing structure can be improved.

One aspect of the present invention relates to a sealed structure including: a to-be-sealed body; and a hardened body of the above-mentioned sealing film for sealing the to-be-sealed body. This seal structure has less warpage.

One aspect of the present invention relates to a method for manufacturing a sealed structure, which includes the step of using a sealing film obtained by the method or the sealing film to seal a to-be-sealed body. According to this method, it is possible to obtain a sealed structure having reduced warpage. [Effect of the invention]

According to the present invention, it is possible to provide a sealing film, a method for manufacturing the same, and a sealing structure obtained by using the sealing film, which can reduce warping of the sealing structure.

The numerical ranges indicated by "~" in this specification include the numerical values described before and after "~" as the minimum and maximum values, respectively. In the numerical ranges described stepwise in this specification, the upper limit or lower limit of the numerical range at one stage may be replaced with the upper limit or lower limit of the numerical range at another stage. Among the numerical ranges described in this specification, the upper limit value or lower limit value of the numerical range may be replaced with the numerical values shown in the examples. "A or B" means that either one of A and B may be included, or both. Unless otherwise specified, the materials exemplified in this specification may be used alone or in combination of two or more. In the present specification, when a plurality of substances are present in the composition in accordance with each component, the content of each component in the composition means the total amount of the plurality of substances present in the composition unless otherwise specified.

Hereinafter, preferred embodiments of the present invention will be described.

The sealing film of this embodiment is a film-like resin composition containing a thermosetting component and an inorganic filler. Examples of the thermosetting component include a thermosetting resin, a curing agent, and a curing accelerator. The thermosetting component may contain a thermosetting resin without containing a hardener and / or a hardening accelerator.

(Thermosetting resin) The thermosetting resin has two or more reactive functional groups in one molecule. In this embodiment, the sealing film is hardened by, for example, forming a three-dimensional crosslinked structure by reacting a reactive functional group with another reactive functional group by heat. The other reactive functional group capable of reacting with the reactive functional group may be a reactive functional group possessed by the thermosetting resin or a reactive functional group possessed by the hardener.

The thermosetting resin can be at least one selected from the group consisting of a thermosetting resin that is liquid at 25 ° C and a thermosetting resin that is not liquid at 25 ° C. In this embodiment, it is preferable to use a thermosetting resin which is liquid at 25 ° C from the viewpoint of easily suppressing occurrence of cracks and cracks on the film surface. In addition, "liquid at 25 ° C" means that the viscosity at 25 ° C measured by an E-type viscometer is 400 Pa · s or less.

The thermosetting resin includes Resin A having a reactive functional group equivalent of more than 250 g / mol. In this specification, "reactive functional group equivalent" means the mass (g / mol) of the thermosetting resin per 1 mol (mol) of the reactive functional group which the thermosetting resin has. For example, when the reactive functional group is an epoxy group, the reactive functional group equivalent is determined by dissolving a thermosetting resin in chloroform, and adding acetic acid and tetraethyl bromide to the obtained solution. The ammonium acetic acid solution was then potentiometrically titrated with a perchloric acid acetic acid standard solution, and the end point of all epoxy groups was detected. In addition, when the reactive functional group is a hydroxyl group, it is measured by adding an ethylated reagent to a thermosetting resin, heating it in a glycerin bath, and leaving it to cool, and then adding phenolphthalein as an indicator. The solution was titrated with a potassium hydroxide ethanol solution.

According to the sealing film of this embodiment, by including the resin A, it is possible to reduce the warpage of the sealing structure obtained by sealing the object to be sealed. According to the knowledge of the present inventors, conventional sealing resins containing epoxy resins and / or phenol resins (for example, sealing films made of sealing resins) are prone to warping of the sealing structure. In this embodiment, even when the sealing film includes an epoxy resin and / or a phenol resin, the warpage of the sealing structure can be reduced. Although the reason why such an effect can be obtained is not clear, the inventors speculate that the reason is that the sealing film contains resin A, so that the crosslinking point at the time of curing is reduced, and the crosslinking density after curing is reduced.

Examples of the resin A include epoxy resin, phenol resin, phenoxy resin, cyanate resin, thermosetting polyimide, melamine resin, urea resin, unsaturated polyester, alkyd resin, and polyurethane. An epoxy resin or a phenol resin is preferable from the viewpoint that a hardened material having excellent thermal conductivity is easily obtained and the effect of the present invention becomes remarkable. When the resin A is an epoxy resin, the reactive functional group is an epoxy group. When the resin A is a phenol resin, the reactive functional group is a hydroxyl group (phenolic hydroxyl group).

From the viewpoint of further reducing the warpage of the sealing structure, the resin A may include a resin having a reactive functional group equivalent of 280 g / mol or more, or a resin having a reactive functional group equivalent of 300 g / mol or more. A resin having a reactive functional group equivalent of 330 g / mol or more may be included. From the viewpoint that the Tg after curing is sufficient and the reliability (thermal reliability) of the sealed structure can be improved, the resin A may include a resin having a reactive functional group equivalent of 500 g / mol or less, and may also include reactivity. The resin having a functional group equivalent of 450 g / mol or less may also include a resin having a reactive functional group equivalent of 410 g / mol or less. From these viewpoints, the resin A may include a resin having a reactive functional group equivalent weight greater than 250 g / mol and less than 500 g / mol, or a resin having a reactive functional group equivalent weight of 280 to 450 g / mol, and may also include a reactive property. The resin having a functional group equivalent of 300 to 410 g / mol may also include a resin having a reactive functional group equivalent of 330 to 410 g / mol.

From the viewpoint of reducing the warpage of the sealing structure and improving the reliability of the sealing structure, the content of the resin A may be 5% by mass or more and 10% by mass based on the total mass of the thermosetting resin. Above, 12% by mass or more, or 15% by mass, and may be 90% by mass or less, 85% by mass or less, 70% by mass or less, or 30% by mass or less. The above upper limit value and lower limit value can be arbitrarily combined. Therefore, the content of the resin A, based on the total mass of the thermosetting resin, may be, for example, 10 to 90% by mass, 12 to 85% by mass, or 15 to 75% by mass, or 5 -30 mass%, 10-30 mass%, or 15-30 mass% may also be sufficient. In addition, in the same description below, the upper limit value and the lower limit value individually described can also be arbitrarily combined.

In particular, from the viewpoint of reducing the warpage of the sealed structure and improving the reliability of the sealed structure at a higher level, the content of the resin having a single reactive functional group in the resin A of 300 to 410 g / mol Based on the total mass of the thermosetting resin, it may be 10 to 90% by mass, 12 to 85% by mass, or 15 to 75% by mass.

In this embodiment, a plurality of types of thermosetting resins having mutually different reactive functional group equivalents are used in combination. In this case, it is possible to achieve both reduction in warpage of the sealed structure and improvement in reliability of the sealed structure. In this case, even when the inorganic filler is increased (for example, when the total mass of the sealing film (excluding the mass of the solvent) is used as a reference and the amount of the inorganic filler is 70% by mass or more), It can also reduce cracks and cracks after hardening. Although the reason why these effects can be obtained is not clear, the inventors speculate that the reason is that the crosslinked structure derived from the resin A can improve the crack resistance.

The thermosetting resin preferably contains resin B, and has a reactive functional group equivalent of 1 / 2.9 to 1/2 times the reactive functional group equivalent of resin A. In this case, it is possible to achieve a higher level of both reducing warpage of the sealed structure and improving reliability of the sealed structure. Although the reason for this is not clear, the inventors speculate that the reason is that by using hardening to form a crosslinked structure having densely crosslinked portions and sparsely crosslinked portions, stress can be suppressed during hardening, and After hardening, sufficient Tg can be ensured. The resin B may include a plurality of types of resins having different reactive functional group equivalents.

When the thermosetting resin contains a plurality of resins A having different reactive functional group equivalents, the resin B has a reactivity of 1 / 2.9 to 1/2 times that of the reactive functional group equivalents of at least one resin A. Functionally equivalent resin is sufficient.

The reactive functional group of the resin B may be the same as or different from the reactive functional group of the resin A. The reactive functional group of the resin B may be a functional group capable of reacting with the reactive functional group of the resin A by heat. For example, when the resin A is an epoxy resin, the resin B may be a phenol resin, a polyamide resin, a carboxylic acid resin, or the like. In addition, for example, when the resin A is a phenol resin, the resin B may be an epoxy resin or the like.

From the standpoint of reducing the warpage of the sealing structure and improving the reliability of the sealing structure at a higher level, the content of the resin B may be 5% by mass based on the total mass of the thermosetting resin. It is 15 mass% or more or 25 mass% or more, and may be 60 mass% or less, 50 mass% or less, or 40 mass% or less. Therefore, the content of the resin B may be 5 to 60% by mass, 15 to 50% by mass, or 25 to 40% by mass based on the total mass of the thermosetting resin.

The thermosetting resin is preferably resin A and resin C having a reactive functional group equivalent of 250 g / mol or less. In this case, it is possible to achieve a higher level of both reducing warpage of the sealed structure and improving reliability of the sealed structure. Although the reason for this is not clear, the inventors speculate that the reason is that by using hardening to form a crosslinked structure having densely crosslinked portions and sparsely crosslinked portions, stress can be suppressed during hardening, and After hardening, sufficient Tg can be ensured.

From the viewpoint of further reducing the warpage of the sealing structure, the resin C may include a resin having a reactive functional group equivalent of 80 g / mol or more, or a resin having a reactive functional group equivalent of 90 g / mol or more. A resin having a reactive functional group equivalent of 100 g / mol or more may be included, and a resin having a reactive functional group equivalent of 130 g / mol or more may be included. From the viewpoint that the Tg after curing is sufficient and the reliability (thermal reliability) of the sealed structure can be improved, the resin C may include a resin having a reactive functional group equivalent of 210 g / mol or less, and may also include reactivity. The resin having a functional group equivalent of 205 g / mol or less may also include a resin having a reactive functional group equivalent of 160 g / mol or less. From these viewpoints, the resin C may include a resin having a reactive functional group equivalent of 80 to 250 g / mol, a resin having a reactive functional group equivalent of 90 to 210 g / mol, or a reactive functional group equivalent. Resins of 100 to 205 g / mol, and resins having a reactive functional group equivalent of 100 to 210 g / mol, and resins having a reactive functional group equivalent of 100 to 160 g / mol or less may be included. The resin having a base equivalent of 130 to 210 g / mol may also include a resin having a reactive functional group equivalent of 130 to 160 g / mol.

The resin C may include a plurality of types of resins having different reactive functional groups. For example, as the resin C, a resin having a reactive functional group equivalent of 100 to 160 g / mol and a resin having a reactive functional group equivalent of 160 to 250 g / mol can be used in combination.

The reactive functional group of the resin C may be the same as or different from the reactive functional group of the resin A. For example, the reactive functional group of the resin C may be a functional group capable of reacting with the reactive functional group of the resin A by heat.

The reactive functional group equivalent of the resin C may be 1 / 2.9 to 1/2 times the reactive functional group equivalent of the resin A. The preferred combination of resin A and resin C is a combination of a resin having a reactive functional group equivalent of 300 to 410 g / mol and a resin having a reactive functional group equivalent of 100 to 210 g / mol, and a more preferable combination is reactivity. A combination of a resin having a functional group equivalent of 330 to 410 g / mol and a resin having a reactive functional group equivalent of 130 to 210 g / mol.

From the viewpoint of reducing the warpage of the sealing structure and improving the reliability of the sealing structure at a higher level, the content of the resin C may be 5% by mass based on the total mass of the thermosetting resin. Above, 15% by mass, 25% by mass, 35% by mass, or 45% by mass, and may be 85% by mass, 75% by mass, 65% by mass, 60% by mass, or 50% by mass Or 40% by mass or less. Therefore, the content of the resin C, based on the total mass of the thermosetting resin, may be, for example, 25 to 85% by mass, or 35 to 75% by mass, or 45 to 65% by mass, or 5 -60% by mass, 15-50% by mass, or 25-40% by mass. In particular, from the viewpoint of reducing the warpage of the sealed structure and improving the reliability of the sealed structure at a higher level, the content of the resin having a reactive functional group equivalent of 100 to 210 g / mol in the resin C, Based on the total mass of the thermosetting resin, it may be 25 to 85% by mass, 35 to 75% by mass, or 45 to 65% by mass.

Next, a first embodiment in which the resin A includes an epoxy resin and a second embodiment in which the resin A includes a phenol resin will be described in detail.

[First Embodiment] The resin A of the sealing film according to the first embodiment contains an epoxy resin. An epoxy resin having a reactive functional group equivalent weight greater than 250 g / mol can be used without particular limitation as long as it is a resin having two or more epoxy groups in one molecule and an epoxy group equivalent weight greater than 250 g / mol.

Examples of the epoxy resin having a reactive functional group equivalent weight greater than 250 g / mol include bisphenol A epoxy resin, bisphenol AP epoxy resin, bisphenol AF epoxy resin, and bisphenol B epoxy resin. Bisphenol BP epoxy resin, bisphenol C epoxy resin, bisphenol E epoxy resin, bisphenol F epoxy resin, bisphenol G epoxy resin, bisphenol M epoxy resin, Phenol S type epoxy resin (hexanediol bisphenol S diglycidyl ether, etc.), bisphenol P type epoxy resin, bisphenol PH type epoxy resin, bisphenol TMC type epoxy resin, bisphenol Z type Epoxy resin, phenol novolac epoxy resin (o-cresol novolac epoxy resin, etc.), biphenyl epoxy resin, naphthalene epoxy resin, dicyclopentadiene epoxy resin, bixylenol Type epoxy resin (bixylenol diglycidyl ether, etc.), hydrogenated bisphenol A type epoxy resin (hydrogenated bisphenol A glycidyl ether, etc.); dibasic acid modified diepoxy of these resins Propyl ether epoxy resin; aliphatic epoxy resin, etc. Among these, an epoxy resin having a bisphenol A skeleton is preferred from the viewpoint of reducing the warpage of the sealed structure and improving the reliability of the sealed structure. An epoxy resin may be used individually by 1 type, and may use 2 or more types together.

From the viewpoint of easily suppressing the occurrence of cracks and cracks on the film surface, as the epoxy resin having a reactive functional group equivalent weight greater than 250 g / mol, a liquid epoxy resin (liquid epoxy resin) at 25 ° C can be used. Examples of the liquid epoxy resin include bisphenol A type glycidyl ether, bisphenol AD type glycidyl ether, bisphenol S type glycidyl ether, bisphenol F type glycidyl ether, Hydrogenated bisphenol A-type epoxypropyl ether, ethylene oxide adducts bisphenol A-type epoxypropyl ether, propylene oxide adducts bisphenol A-type epoxypropyl ether, naphthalene resin epoxypropyl ether, 3-functional or 4-functional epoxypropylamine.

From the viewpoint of further reducing the warpage of the sealing structure, the reactive functional group equivalent of the epoxy resin having a reactive functional group equivalent of more than 250 g / mol is preferably 280 g / mol, more preferably 300 g / mol, further More preferably, it is 330 g / mol. From the viewpoint that the Tg after curing becomes sufficient and the reliability (thermal reliability) of the sealed structure can be improved, the reactive functional group equivalent of the epoxy resin having a reactive functional group equivalent of more than 250 g / mol is preferably 500 g / mol or less, more preferably 450 g / mol or less, even more preferably 410 g / mol or less. From such a viewpoint, the reactive functional group equivalent of the epoxy resin having a reactive functional group equivalent of more than 250 g / mol is preferably greater than 250 g / mol and 500 g / mol or less, more preferably 280 to 450 g / mol, and further It is more preferably 300 to 410 g / mol, and particularly preferably 330 to 410 g / mol.

Examples of commercially available epoxy resins having a reactive functional group equivalent weight greater than 250 g / mol include "EXA4816", "EXA4850-1000", and "EXA4850-150" manufactured by DIC Corporation.

From the viewpoint of reducing the warpage of the sealing structure and improving the reliability of the sealing structure, the content of the epoxy resin having a reactive functional group equivalent of more than 250 g / mol is based on the total mass of the thermosetting resin. It may be 5 mass% or more, 10 mass% or more, or 15 mass% or more, and may also be 90 mass% or less, 85 mass% or less, or 75 mass% or less. Therefore, the content of the epoxy resin having a reactive functional group equivalent weight greater than 250 g / mol, based on the total mass of the thermosetting resin, may be, for example, 5% to 90% by mass, or 10% to 85% by mass. It can also be 15% to 75% by mass. In particular, from the viewpoint of reducing the warpage of the sealed structure and improving the reliability of the sealed structure at a higher level, the content of the epoxy resin having a reactive functional group equivalent of 300 to 410 g / mol is based on heat. The total mass of the curable resin may be 5 to 90% by mass, 10 to 85% by mass, or 15 to 75% by mass.

The liquid epoxy resin having a reactive functional group equivalent weight greater than 250 g / mol, based on the total mass of the thermosetting resin, may be 5 mass% or more, 10 mass% or more, or 15 mass% or more, or 90 mass % Or less, 85% by mass or less, or 75% by mass or less. Therefore, for a liquid epoxy resin having a reactive functional group equivalent weight greater than 250 g / mol, based on the total mass of the thermosetting resin, it may be, for example, 5% to 90% by mass, or 10% to 85% by mass. It can also be 15% to 75% by mass. When the content of the liquid epoxy resin having a reactive functional group equivalent of more than 250 g / mol is equal to or more than the above-mentioned lower limit value, it is easy to suppress the occurrence of cracks and cracks on the surface of the film. In addition, when the content of the liquid epoxy resin having a reactive functional group equivalent of more than 250 g / mol is equal to or less than the above-mentioned upper limit value, it is easy to suppress an excessively high viscosity of the film and to easily suppress edge fusion.

The thermosetting resin may contain an epoxy resin having a reactive functional group equivalent of 250 g / mol or less. Examples of the epoxy resin having a reactive functional group equivalent weight of 250 g / mol or less include, for example, bisphenol A epoxy resin, bisphenol AP epoxy resin, bisphenol AF epoxy resin, and bisphenol B epoxy resin. Resin, bisphenol BP epoxy resin, bisphenol C epoxy resin, bisphenol E epoxy resin, bisphenol F epoxy resin, bisphenol G epoxy resin, bisphenol M epoxy resin, Bisphenol S epoxy resin (hexanediol bisphenol S diglycidyl ether, etc.), bisphenol P epoxy resin, bisphenol PH epoxy resin, bisphenol TMC epoxy resin, bisphenol Z Epoxy resin, phenol novolac epoxy resin (o-cresol novolac epoxy resin, etc.), biphenyl epoxy resin, naphthalene epoxy resin, dicyclopentadiene epoxy resin, bidimethyl Phenol-type epoxy resins (bixylenol diglycidyl ether, etc.), hydrogenated bisphenol A type epoxy resins (hydrogenated bisphenol A glycidyl ether, etc.); dibasic acid modified bicyclics of these resins Oxypropyl ether type epoxy resin; aliphatic epoxy resin, etc. The epoxy resin having a reactive functional group equivalent weight of 250 g / mol or less may be used singly or in combination of two or more kinds.

From the viewpoint of easily obtaining excellent fluidity, the content of the entire epoxy resin contained in the sealing film may be 1% by mass based on the total mass of the sealing film (excluding the mass of the solvent), or may be 3 mass% or more, 4 mass% or more, 4 mass% or more, 5 mass% or more, 10 mass% or more, or 15 mass% or more. From the viewpoint of easily suppressing the occurrence of cracks and cracks on the surface of the film, the content of the entire epoxy resin contained in the sealing film may be 30% by mass or less based on the total mass of the sealing film (excluding the mass of the solvent). It may be 25% by mass or less, or 20% by mass or less. Therefore, the content of the entire epoxy resin contained in the sealing film may be, for example, 1 to 30% by mass based on the total mass of the sealing film (excluding the mass of the solvent).

The thermosetting resin may further include a resin having a functional group: a functional group capable of reacting with an epoxy resin having a reactive functional group equivalent weight greater than 250 g / mol by heat. For example, the thermosetting resin preferably contains a phenol resin. As a phenol resin, if it is a resin which has two or more phenolic hydroxyl groups in one molecule, a well-known phenol resin can be used without a restriction | limiting.

Examples of the phenol resin include a resin obtained by condensing or co-condensing phenols and / or naphthols with an aldehyde under an acidic catalyst, a biphenyl skeleton type phenol resin, a p-xylene modified phenol resin, M-xylene / p-xylene modified phenol resin, melamine modified phenol resin, terpene modified phenol resin, dicyclopentadiene modified phenol resin, cyclopentadiene modified phenol resin, polycyclic aromatic ring modified phenol Resin, xylene modified naphthol resin, etc. Examples of the phenols include phenol, phenol containing substituents, cresol, xylenol, resorcinol, catechol, bisphenol A, and bisphenol F. Examples of naphthols include α-naphthol, β-naphthol, and dihydroxynaphthalene. Examples of the aldehydes include formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, and salicylaldehyde.

From the viewpoint of reducing the warpage of the sealing structure and improving the reliability of the sealing structure at a higher level, the reactive functional group equivalent of the epoxy resin having a reactive functional group equivalent of more than 250 g / mol, The reactive functional group equivalent of the phenol resin may be 1 / 2.9 to 1/2 times.

From the viewpoint of reducing the warpage of the sealing structure and improving the reliability of the sealing structure at a higher level, the reactive functional group equivalent of the epoxy resin having a reactive functional group equivalent of more than 250 g / mol, The content of the phenol resin having a reactive functional group equivalent of 1 / 2.9 to 1/2 times, based on the total mass of the thermosetting resin, may be 15% by mass, 20% by mass, or 25% by mass. In addition, it may be 95% by mass or less, 90% by mass or less, or 85% by mass or less. Therefore, the content of the phenol resin may be, for example, 15 to 95% by mass, 20 to 90% by mass, or 25 to 85% by mass based on the total mass of the thermosetting resin.

From the viewpoint of reducing the warpage of the sealed structure and improving the reliability of the sealed structure at a higher level, the reactive functional group equivalent of the phenol resin may be 250 g / mol or less. From the viewpoint of further reducing the warpage of the sealing structure, the reactive functional group equivalent of the phenol resin may be 210 g / mol or less, 205 g / mol or less, or 160 g / mol or less. From the viewpoint that the Tg after curing is sufficient and the reliability (thermal reliability) of the sealed structure can be improved, the reactive functional group equivalent of the phenol resin may be 80 g / mol or more, or 90 g / mol or more. , Can also be 100g / mol. Therefore, the reactive functional group equivalent of the phenol resin may be, for example, 80 to 250 g / mol, 90 to 210 g / mo, 100 to 210 g / mol, 100 to 205 g / mol, or 100 to 160 g / mol, 130 to 210 g / mol, or 130 to 160 g / mol.

The thermosetting resin may include a plurality of phenol resins having different reactive functional group equivalents. For example, the thermosetting resin may include a phenol resin having a reactive functional group equivalent of 100 to 160 g / mol and a phenol resin having a reactive functional group equivalent of 160 to 250 g / mol.

Examples of the phenol resin having a reactive functional group equivalent of 250 g / mol or less include a phenol resin having a structural unit represented by the following formula (1). In the formula (1), R ¹ represents a hydrocarbon group having 2 to 25 carbon atoms. When the number of structural units represented by the formula (1) is plural, each of the plural R ¹ may be the same or different. The position of R ¹ may be any of the ortho, meta or para positions relative to -OH; the position of the bond (-* and -CH _2- *) may be ortho, Either meta or counter.

The hydrocarbon group represented by R ¹ may be either linear or branched. The hydrocarbon group may be either saturated or unsaturated. When the hydrocarbon group is an unsaturated hydrocarbon group, the unsaturated hydrocarbon group may have two or more unsaturated bonds. The carbon number of the hydrocarbon group may be 4 to 22, 8 to 20, or 10 to 18.

The phenol resin having a structural unit represented by the above-mentioned formula (1) may be composed of only the structural unit represented by the above-mentioned formula (1), or may further have a structural unit other than the structural unit represented by the above-mentioned formula (1). . The phenol resin may be, for example, a random copolymer of a structural unit represented by the formula (1) and other structural units, or may be a block including a structural unit represented by the formula (1) and another structural unit. Random block copolymer.

As another structural unit, the structural unit represented by following formula (2) is mentioned. In formula (2), R ² represents a hydrogen atom or a phenyl group. When the number of structural units represented by formula (2) is plural, each of the plural R ² may be the same or different. The position of R ² may be any of the ortho, meta, or para positions relative to -OH; the position of the bond (-* and -CH _2- *) may be ortho, Either meta or counter.

The content of the structural unit represented by the above formula (1) in the phenol resin may be 20 to 100 mol% or 30 to 90 mol based on the total amount of the structural units constituting the phenol resin. %, Or 40 to 80 mole%.

The content of the structural unit represented by the above formula (2) in the above phenol resin, based on the total amount of the structural units constituting the phenol resin, may be more than 0 mol% and 80 mol% or less, or may be 10 ~ 70 mol%, but also 20 ~ 60 mol%.

A phenol resin having a structural unit represented by the above-mentioned formula (1) can be obtained, for example, by using a substituent-containing phenol and formaldehyde represented by the following formula (3) according to the situation and the following formula (4) The substituent-containing phenol represented by) is reacted. Moreover, the example of R ¹ in the following formula (3) is the same as the example of R ¹ in the above formula (1) ^; the example of R ² in the following formula (4) is the same as in the above formula (2) The example of R ^{2 is} the same.

From the viewpoint of reducing the warpage of the sealing structure and improving the reliability of the sealing structure at a higher level, the content of the phenol resin having a reactive functional group equivalent of 250 g / mol or less is based on the thermosetting resin. The total mass can be 15 mass% or more, 20 mass% or more, or 25 mass%, or 95 mass% or less, 90 mass% or less, or 85 mass% or less. Therefore, the content of the phenol resin having a reactive functional group equivalent weight of 250 g / mol or less may be based on the total mass of the thermosetting resin, for example, 15 to 95% by mass, or 20 to 90% by mass, or may be It is 25 to 85% by mass. Especially from the viewpoint of reducing the warpage of the seal structure and improving the reliability of the seal structure at a higher level, the content of the phenol resin having a reactive functional group equivalent of 100 to 210 g / mol is cured by heat. The total mass of the resin is 15 to 95% by mass, 20 to 90% by mass, or 25 to 85% by mass.

The content of the entire phenol resin contained in the sealing film can be appropriately set in consideration of the content of the epoxy resin and the epoxy equivalent of the epoxy resin. From the viewpoint that it is difficult to leave unreacted epoxy resin and / or unreacted phenol resin and it is easy to obtain desired characteristics of the cured product, the molar number M2 of the epoxy group in the sealing film is higher than that of the phenolic hydroxyl group. The ratio of the number of ears M1 (M2 / M1) may be 0.7 or more, 0.8 or more, or 0.9 or more, and may be 2.0 or less, 1.8 or less, or 1.7 or less. Therefore, the ratio (M2 / M1) of the molar number M2 of the epoxy group to the molar number M1 of the phenolic hydroxyl group in the sealing film may be, for example, 0.7 to 2.0, 0.8 to 1.8, or 0.9 to 1.7.

[Second Embodiment] The resin A of the sealing film of the second embodiment contains a phenol resin. As long as the phenol resin having a reactive functional group equivalent weight greater than 250 g / mol is a resin having two or more phenolic hydroxyl groups in one molecule and the phenolic hydroxyl equivalent weight is greater than 250 g / mol, a known phenol resin can be used without particular limitation.

Examples of the phenol resin include a resin obtained by condensing or co-condensing phenols and / or naphthols with an aldehyde under an acidic catalyst, a biphenyl skeleton type phenol resin, a p-xylene modified phenol resin, M-xylene / p-xylene modified phenol resin, melamine modified phenol resin, terpene modified phenol resin, dicyclopentadiene modified phenol resin, cyclopentadiene modified phenol resin, polycyclic aromatic ring modified phenol Resin, xylene modified naphthol resin, etc. A phenol resin may be used individually by 1 type, and may use 2 or more types together.

From the viewpoint of reducing the crosslinking point and reducing warpage, the reactive functional group equivalent of a phenol resin having a reactive functional group equivalent of more than 250 g / mol may be greater than 250 g / mol and less than 500 g / mol, or may be 280. ~ 450 g / mol, 300-410 g / mol, or 330-410 g / mol.

From the viewpoint of reducing the warpage of the sealing structure and improving the reliability of the sealing structure, the content of the phenol resin having a reactive functional group equivalent of more than 250 g / mol is based on the total mass of the thermosetting resin. It may be 5 to 85% by mass, 10 to 80% by mass, or 15 to 75% by mass. Especially from the viewpoint of reducing the warpage of the seal structure and improving the reliability of the seal structure at a higher level, the content of the phenol resin having a reactive functional group equivalent of 300 to 410 g / mol is heat-cured. As a reference, the total mass of the resin can be 5 to 85% by mass, 10 to 80% by mass, or 15 to 75% by mass.

The thermosetting resin may include a phenol resin having a reactive functional group equivalent of 250 g / mol or less.

From the viewpoint of easy to obtain excellent fluidity and to suppress the occurrence of cracks and cracks on the surface of the film, the content of the entire phenol resin contained in the sealing film is the total mass of the sealing film (except the quality of the solvent) as The reference meter may be 15 to 95% by mass, 20 to 90% by mass, or 25 to 85% by mass.

The thermosetting resin may further include a resin having a functional group: a functional group capable of reacting with a phenol resin having a reactive functional group equivalent weight greater than 250 g / mol by heat. For example, the thermosetting resin preferably contains an epoxy resin. As the epoxy resin, as long as it is a resin having two or more epoxy groups in one molecule, a known epoxy resin can be used without particular limitation.

As the epoxy resin, the epoxy resins having an epoxy functional group equivalent of more than 250 g / mol and the epoxy resins having a reactive functional group equivalent of 250 g / mol or less can be used.

From the viewpoint of achieving a higher level of both reducing the warpage of the sealed structure and improving the reliability of the sealed structure, the reactive functional group equivalent of the phenol resin having a reactive functional group equivalent of greater than 250 g / mol, the ring The reactive functional group equivalent of the oxygen resin may be 1 / 2.9 to 1/2 times.

From the viewpoint of achieving a higher level of reducing the warpage of the sealed structure and improving the reliability of the sealed structure, it has a reactive functional group equivalent of a phenol resin having a reactive functional group equivalent of more than 250 g / mol. The content of the epoxy resin with a reactive functional group equivalent of 1 / 2.9 to 1/2 times, based on the total mass of the thermosetting resin, may be 15 to 95% by mass, or 20 to 90% by mass. It may be 25 to 85% by mass.

From the viewpoint of reducing the warpage of the sealed structure and improving the reliability of the sealed structure at a higher level, the reactive functional group equivalent of the epoxy resin may be 250 g / mol or less. From the viewpoint of further reducing the warpage of the sealing structure, the reactive functional group equivalent of the epoxy resin may be 80 to 250 g / mol, 90 to 210 g / mol, or 100 to 205 g / mol. , Can also be 100-160g / mol.

From the viewpoint of reducing the warpage of the sealing structure and improving the reliability of the sealing structure at a higher level, the content of the epoxy resin having a reactive functional group equivalent of 250 g / mol or less is used as the thermosetting resin. As a reference, the total mass may be 15 to 95% by mass, 20 to 90% by mass, or 25 to 85% by mass.

The content of the entire epoxy resin contained in the sealing film can be appropriately set in consideration of the content of the phenol resin and the phenolic hydroxyl equivalent of the phenol resin. The range of the ratio of the molar number M2 of the epoxy group to the molar number M1 of the phenolic hydroxyl group in the sealing film may be the same as the range exemplified in the first embodiment.

(Hardener) The sealing film of this embodiment may contain a hardener (other than a component conforming to a thermosetting resin) as a thermosetting component. The hardener is not particularly limited, and examples thereof include a phenol-based hardener, an acid anhydride-based hardener, an active ester-based hardener, and a cyanate-based hardener. When a thermosetting resin contains an epoxy resin, as a hardener, if it is a compound which has 2 or more functional groups which can react with an epoxy group in a molecule | numerator, it can be used without a restriction | limiting in particular. Moreover, when a thermosetting resin contains a phenol resin, as a hardener, if it is a compound which has two or more functional groups which can react with a phenolic hydroxyl group in a molecule | numerator, it can be used without a restriction | limiting in particular. A hardening agent may be used individually by 1 type, and may use 2 or more types together. When the thermosetting resin contains a plurality of resins having different reactive functional groups, a plurality of curing agents may be used in combination according to the types of the reactive functional groups.

From the viewpoint of excellent curability of the thermosetting resin, the content of the curing agent may be 1 to 20% by mass or 2 to 15 based on the total mass of the sealing film (excluding the mass of the solvent). The mass% may be 3 to 10 mass%.

(Hardening accelerator) The sealing film of this embodiment may contain a hardening accelerator as a thermosetting component. The hardening accelerator can be used without particular limitation, and it is preferably at least one selected from the group consisting of an amine-based hardening accelerator and a phosphorus-based hardening accelerator. In particular, from the viewpoint of easily obtaining a hardened material having excellent thermal conductivity, from the viewpoint of rich derivatives, and from the viewpoint of easily obtaining a desired active temperature, as the hardening accelerator, an amine-based hardening accelerator is preferred, and more preferably It is at least one selected from the group consisting of an imidazole compound, an aliphatic amine, and an alicyclic amine, and more preferably an imidazole compound. Examples of the imidazole compound include 2-phenyl-4-methylimidazole and 1-benzyl-2-methylimidazole. A hardening accelerator may be used individually by 1 type, and may use 2 or more types together. Examples of commercially available hardening accelerators include "2P4MZ" and "1B2MZ" manufactured by Shikoku Chemical Industry Co., Ltd.

The content of the curing accelerator is based on the total amount of the thermosetting resin, and is preferably in the following range. From the viewpoint of easily obtaining a sufficient hardening promoting effect, the content of the hardening accelerator is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and still more preferably 0.3% by mass or more. From the standpoint that hardening does not easily progress during the steps (such as coating and drying) when manufacturing the sealing film or during storage of the sealing film, and it is easy to prevent cracking of the sealing film and poor molding due to an increase in melt viscosity, The content of the hardening accelerator is preferably 5% by mass or less, more preferably 3% by mass or less, and still more preferably 1.5% by mass or less. From these viewpoints, the content of the hardening accelerator is preferably 0.01 to 5% by mass, more preferably 0.1 to 3% by mass, and still more preferably 0.3 to 1.5% by mass.

(Inorganic Filler) As the inorganic filler, a conventionally known inorganic filler can be used, and it is not particularly limited. Examples of the constituent material of the inorganic filler include silicon dioxide (amorphous silicon dioxide, crystalline silicon dioxide, fused silicon dioxide, spherical silicon dioxide, synthetic silicon dioxide, hollow silicon dioxide, etc.) , Barium sulfate, barium titanate, talc, clay, mica powder, magnesium carbonate, calcium carbonate, alumina, aluminum hydroxide, magnesium oxide, magnesium hydroxide, silicon nitride, aluminum nitride, aluminum borate, nitrogen Boron, barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate and the like. From the viewpoint of easily using surface modification (such as surface treatment with a silane compound) to obtain the effect of improving the dispersibility in the resin composition and the effect of suppressing the precipitation in the varnish, and to easily obtain a desired cured film From the viewpoint of having a small thermal expansion coefficient, an inorganic filler containing silicon dioxide is preferred. From the viewpoint of obtaining high thermal conductivity, an inorganic filler containing alumina is preferred. The inorganic filler may be used singly or in combination of two or more kinds.

Surface modification of inorganic fillers. The method for surface modification is not particularly limited. From the viewpoint of easy handling, abundant functional group types, and easy provision of desired characteristics, surface modification using a silane coupling agent is preferred.

Examples of the silane coupling agent include alkyl silane, alkoxy silane, vinyl silane, epoxy silane, amino silane, acryl silane, methacryl silane, thiol silane, thioether silane, isosilane Cyanosilane, thiosilane, styrylsilane, alkylchlorosilane, etc.

Specific examples of the silane coupling agent include methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, methyltriethoxysilane, and methyltriethoxysilane. , Ethyltrimethoxysilane, n-propyltrimethoxysilane, diisopropyldimethoxysilane, isobutyltrimethoxysilane, diisobutyldimethoxysilane, isobutyltriethoxy Silane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, cyclohexylmethyldimethoxysilane, n-octyltriethoxysilane, n-decylmethoxysilane, phenyltrimethoxy Silane, diphenyldimethoxysilane, triphenylsilanol, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, n-octyldimethylchlorosilane, tetraethoxysilane , 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3- (2-aminoethyl) aminopropyltrimethoxysilane, 3- (2-amino group (Ethyl) aminopropylmethyldimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyl Methyldimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, bis (3- (triethyl disulfide) Oxysilyl) propyl), bis (3- (triethoxysilyl) propyl) tetrasulfide, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane , Vinyltriisopropoxysilane, allyltrimethoxysilane, diallyldimethylsilane, 3-methylpropoxypropyltrimethoxysilane, 3-methylpropoxysilane Propylmethyldimethoxysilane, 3-methylpropanyloxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3 -Mercaptopropyltriethoxysilane, N- (1,3-dimethylbutylene) -3-aminopropyltriethoxysilane, aminosilane (phenylaminosilane, etc.), and the like. The silane coupling agent may be used singly or in combination of two or more kinds.

From the standpoint of easily inhibiting the aggregation of the inorganic filler and thereby easily dispersing the inorganic filler, the average particle diameter of the inorganic filler is preferably 0.01 μm or more, more preferably 0.1 μm or more, and still more preferably 0.3 μm or more. It is preferably at least 0.5 μm. The average particle diameter of the inorganic filler is preferably 25 μm or less, more preferably 10 μm or less, and further more preferably, from the viewpoint that it is easy to suppress the precipitation of the inorganic filler in the varnish and it is easy to produce a homogeneous sealing film. 5 μm or less. From these viewpoints, the average particle diameter of the inorganic filler is preferably 0.01 to 25 μm, more preferably 0.01 to 10 μm, still more preferably 0.1 to 10 μm, particularly preferably 0.3 to 5 μm, and most preferably 0.5 to 5 μm. The average particle diameter of the inorganic filler may be 10 to 18 μm.

From the viewpoint of excellent fluidity of the resin composition, it is preferable to use a plurality of inorganic fillers having different average particle diameters in combination. In the combination of inorganic fillers, the maximum average particle diameter is preferably 15 to 25 μm. An inorganic filler having an average particle diameter of 15 to 25 μm, an inorganic filler having an average particle diameter of 0.5 to 2.5 μm, and an inorganic filler having an average particle diameter of 0.1 to 1.0 μm are preferably used in combination.

"Average particle diameter" is a particle diameter equivalent to 50% of the volume when the total volume of the particles is set to 100% and a cumulative frequency distribution curve based on the particle diameter is obtained. The measurement was performed by a distribution measuring device using a laser diffraction scattering method. The average particle diameter of each inorganic filler after combination can be confirmed from the average particle diameter of each inorganic filler at the time of mixing, and can also be confirmed by measuring a particle size distribution.

Examples of commercially available inorganic fillers include "DAW20" manufactured by Denka Corporation; trade names "SC550O-SXE" and "SC2050-KC" manufactured by Admatechs Corporation.

From the viewpoint of improving the thermal conductivity and easily suppressing the warpage of the sealing structure (such as an electronic component device such as a semiconductor device) from increasing due to a difference in the coefficient of thermal expansion with the sealed body, an inorganic filler The content may be 70% by mass or more, 75% by mass or more, and 80% by mass or more based on the total mass of the sealing film (excluding the mass of the solvent). From the viewpoint that it is easy to suppress cracking of the sealing film in the drying step when producing the sealing film, and from suppressing the decrease in fluidity due to an increase in the melt viscosity of the sealing film, it is easy to sufficiently seal the sealed body (electronic parts, etc.). The content of the inorganic filler may be 93 mass% or less, 91 mass% or less, or 88 mass% or less based on the total mass of the sealing film (excluding the mass of the solvent) as a reference. From these viewpoints, the content of the inorganic filler may be 70 to 93% by mass, or 75 to 91% by mass, or 80% based on the total mass of the sealing film (excluding the mass of the solvent). ～ 88% by mass. The above-mentioned content is the content of the inorganic filler after excluding the amount of the surface treatment agent.

(Elastomer) The sealing film of this embodiment may contain an elastomer (flexible material) as needed. From the viewpoint of excellent dispersibility and solubility, the elastomer is preferably selected from the group consisting of polybutadiene particles, styrene butadiene particles, acrylic elastomers, polysiloxane powder, silicone oil, and silicone. At least one of the group consisting of oligomers. The elastomer may be used singly or in combination of two or more kinds.

When the elastomer is particulate, the average particle diameter of the elastomer is not particularly limited. For embedded Wafer-Level Ball Grid Array (eWLB) applications, since semiconductor elements need to be embedded, when the sealing film is used for eWLB applications, the average particle diameter of the elastomer Is preferably 50 μm or less. From the viewpoint of excellent dispersibility of the elastomer, the average particle diameter of the elastomer is preferably 0.1 μm or more.

Examples of commercially available elastomers include "SG-280 EK23", "SG-70L", and "WS-023 EK30", which are acrylic elastomers manufactured by Nagase ChemteX Corporation. In addition, among the commercially available elastomer components, there is an elastomer component previously dispersed in a liquid resin (for example, a liquid epoxy resin), rather than a separate elastomer, and can be used without any problem. Examples of such commercially available products include "MX-136" and "MX-965" manufactured by KANEKA Corporation.

From the viewpoint of imparting flexibility to the film and improving cracking, the amount of addition is not particularly limited. The content of the elastomer may be 1% by mass or more based on the total amount of the thermosetting component and the elastomer as a reference. It is 5 mass% or more, and may be 10 mass% or more. From the viewpoint of ensuring the fluidity required for embedding, etc., the content of the elastomer may be 30% by mass or less, or 25% by mass or less based on the total amount of the thermosetting component and the elastomer. It may be 20% by mass or less. From the above point of view, the content of the elastomer may be 1 to 30% by mass, 5 to 25% by mass, or 10 to 20% by mass based on the total amount of the thermosetting component and the elastomer. %the following.

(Other components) The sealing film of this embodiment can further contain other additives. Specific examples of such additives include pigments, dyes, release agents, antioxidants, and surface tension adjusters.

The sealing film of the present embodiment may contain a solvent (for example, a solvent used when preparing a sealing film). The solvent may be a conventionally known organic solvent. The organic solvent may be a solvent capable of dissolving components other than the inorganic filler, and examples thereof include aliphatic hydrocarbons, aromatic hydrocarbons, terpene, halogens, esters, ketones, alcohols, Aldehydes, etc. A solvent may be used individually by 1 type, and may use 2 or more types together.

The solvent may be at least one selected from the group consisting of esters, ketones, and alcohols from the viewpoint of a small environmental load and a viewpoint of easily dissolving a thermosetting component. Among them, when the solvent is a ketone, it is particularly easy to dissolve the thermosetting component. From the viewpoint of less volatilization at room temperature (25 ° C) and easy removal during drying, the solvent may be selected from the group consisting of acetone, methyl ethyl ketone, and methyl isobutyl ketone. At least one.

Content of the solvent (organic solvent etc.) contained in the sealing film with respect to the total mass (mass including a solvent) of the sealing film is preferably in the following range. The content of the solvent may be 0.2% by mass or more, from the viewpoints that it is easy to prevent the sealing film from becoming brittle and causing problems such as cracking of the sealing film and the case where the minimum melt viscosity becomes high and the embedding property decreases. It is 0.3 mass% or more, may be 0.5 mass% or more, may be 0.6 mass% or more, and may be 0.7 mass% or more. The content of the solvent is from the viewpoints that it is easy to suppress the disadvantages that the adhesiveness of the sealing film becomes too strong and the operability is reduced, and that the solvent (organic solvent, etc.) is volatilized during the thermal curing of the sealing film, which causes problems such as foaming. It may be 1.5% by mass or less, or 1% by mass or less. From these viewpoints, the content of the solvent may be 0.2 to 1.5% by mass, 0.3 to 1% by mass, 0.5 to 1% by mass, 0.6 to 1% by mass, or 0.7 to 1% by mass. 1% by mass.

The sealing film according to this embodiment can be used for, for example, sealing of semiconductor devices, embedding of electronic components arranged on a printed wiring board, and the like. In particular, the sealing film of this embodiment can be suitably used for sealing thin semiconductor devices without a package substrate, such as a fan-out fan-out wafer-level package and a fan-out panel-level package.

The thickness of the sealing film may be 20 μm or more, or 30 μm or more, from the viewpoint that it is easy to suppress variations in the thickness of the surface during coating and to improve the reliability of the sealing structure. It is 50 μm or more, and may be 100 μm or more. The thickness of the sealing film may be 250 μm or less, or 200 μm or less, from the viewpoint of easily obtaining a certain level of dryness in the depth direction during coating, and from the viewpoint of reducing warpage of the sealing structure. It may be 150 μm or less. From these viewpoints, the thickness of the sealing film may be 20 to 250 μm, 30 to 250 μm, 50 to 200 μm, or 100 to 150 μm. Moreover, the thickness of several sealing films can be laminated | stacked, and the sealing film whose thickness exceeds 250 micrometers can be manufactured.

From the viewpoint of excellent reliability (thermal reliability) of the obtained sealed structure, the glass transition temperature after the sealing film is cured may be 80 ° C. or higher, or 100 ° C. or higher. From the viewpoint of excellent reliability (thermal reliability) of the obtained sealing structure, the glass transition temperature after the sealing film is cured may be 180 ° C. or lower, or may be 165 ° C. or higher, or 150 ° C. or higher. . From these viewpoints, the glass transition temperature after curing of the sealing film may be 80 to 180 ° C, 80 to 165 ° C, 80 to 150 ° C, or 100 to 150 ° C. The glass transition temperature of the sealing film can be adjusted using the type and content of the thermosetting component, the type and content of the elastomer component, and the like. The glass transition temperature can be measured by the method described in Examples.

The sealing film of this embodiment can also be used as a sealing film with a support, for example. The sealing film 10 with a support shown in FIG. 1 includes a support 1 and a sealing film 2 provided on the support 1.

As the support 1, a polymer film, a metal foil, or the like can be used. Examples of the polymer film include polyolefin films such as polyethylene films and polypropylene films; vinyl films such as polyvinyl chloride films; polyester films such as polyethylene terephthalate films; polycarbonate films; acetate fibers Plain film; tetrafluoroethylene film, etc. Examples of the metal foil include copper foil and aluminum foil.

The thickness of the support 1 is not particularly limited, but may be 2 to 200 μm from the viewpoint of excellent workability and dryness. When the thickness of the support 1 is 2 μm or more, it is easy to suppress the failure of the support during coating, the failure of the support to bend due to the weight of the varnish, and the like. When the thickness of the support 1 is 200 μm or less, in the drying step, when hot air is blown from both sides of the coating surface and the back surface, it is easy to suppress a problem that the drying of the solvent in the varnish is prevented.

In this embodiment, the support body 1 may not be used. A protective layer may be disposed on the side of the sealing film 2 opposite to the support 1, and the purpose of the protective layer is to protect the sealing film. By forming a protective layer on the sealing film 2, the operability can be improved, and a trouble such as the sealing film sticking to the back surface of the support when the winding is performed can be avoided.

As the protective layer, a polymer film, a metal foil, or the like can be used. Examples of the polymer film include polyolefin films such as polyethylene films and polypropylene films; vinyl films such as polyvinyl chloride films; polyester films such as polyethylene terephthalate films; polycarbonate films; acetate fibers Plain film; tetrafluoroethylene film, etc. Examples of the metal foil include copper foil and aluminum foil.

However, in the sealing of electronic parts, a mold is sometimes used. The mold is formed by using a metal mold to form a solid or liquid resin sealing material. For example, transfer molding is used, which is performed by melting a pellet-shaped resin sealing material and flowing the resin into a mold to perform sealing. However, in the injection molding, since the molten resin is flowed in for molding, when a large area is to be sealed, an unfilled portion may occur. Therefore, in recent years, compression molding has been used, in which a resin sealing material is supplied to a metal mold or a sealed body in advance, and then molding is performed. In compression molding, since a resin sealing material is directly supplied to a mold or a to-be-sealed body, there is an advantage that even in a large-area seal, an unfilled portion is less likely to occur.

In compression molding, a solid or liquid resin sealing material can be used in the same manner as in transfer molding. However, when the object to be sealed is enlarged, liquid resin sealing material may cause liquid flow and the like, and it is difficult to uniformly supply the object to the object to be sealed. In addition, since it is necessary to uniformly supply the resin to the object to be sealed, as a solid resin sealing material, a granular or powder resin sealing material may be used instead of the conventional pellet-shaped resin. However, it is difficult to supply the resin sealing material to the metal mold or the sealed body uniformly with the resin sealing material of particles or powders, and the resin sealing material becomes a source of dust due to the particles or powders. Pollution to the device or clean room.

In addition, since the resin is formed in a metal mold during molding, the metal mold must be enlarged in order to increase the size of the sealing structure. However, since the size of a metal mold is required to be high, the technical difficulty is increased, and the manufacturing cost of the metal mold is greatly increased.

On the other hand, according to the said sealing film, resin can be uniformly supplied to a to-be-sealed body, and dust generation can be reduced. In addition, embedding capability can be obtained, which can not only perform sealing by molding, but also a forming method (laminating, pressing, etc.) by a mold that does not require a mold (such as a mold for high pressure). ) To implement the seal.

The sealing film of this embodiment is suitable for sealing electronic components. In particular, it can be suitably used for sealing electronic components in thin semiconductor devices without a package substrate, such as a fan-out fan-out wafer-level package and a fan-out panel-level package.

<The manufacturing method of the sealing film> The manufacturing method of the sealing film 2 of this embodiment is provided with the process of preparing the resin composition (preparation process) containing the reactive function as a thermosetting resin A resin having a base equivalent of more than 250 g / mol, and an inorganic filler; and a step of forming the resin composition into a thin film (forming step).

In the preparation step, the varnish (varnish-like resin composition) is prepared by mixing the constituents (thermosetting resin, hardener, hardening accelerator, inorganic filler, solvent, etc.) of the sealing film 2 of this embodiment. The mixing method is not particularly limited, and a mill, a mixer, or a stirring blade can be used. The solvent (organic solvent) can be used to dissolve and disperse the material of the sealing film 2, that is, the constituents of the resin composition to prepare a varnish, or can be used to assist in the preparation of a varnish. Most of the solvent can be removed by the drying step after coating.

In the forming step, for example, the varnish is applied to the support 1 (thin film support or the like), and then heated and dried by blowing hot air or the like. Thereby, the varnish can be formed into a thin film to obtain a sealing film 10 with a support, which includes the sealing film 2. The coating method is not particularly limited, and examples thereof include a corner wheel coater, a bar coater, a kiss coater, a roll coater, and a gravure coater. , Die coating machine and other coating devices.

<Sealed Structure> The sealed structure of this embodiment includes a to-be-sealed body and a hardened body (sealed portion) of the sealing film of this embodiment, and the hardened body is used to seal the to-be-sealed body. Examples of the sealed structure include electronic component devices. The electronic component device includes an electronic component as a sealed body. Examples of the electronic component include semiconductor elements, semiconductor wafers, integrated circuits, semiconductor devices, filters such as surface acoustic wave (SAW) filters, and passive components such as sensors. A semiconductor element obtained by singulating a semiconductor wafer can be used. The electronic component device may be a semiconductor device including a semiconductor element or a semiconductor wafer as an electronic component, a printed wiring board, and the like. The sealed structure of the present embodiment may include a plurality of sealed bodies. The plurality of sealed bodies may be the same type or different types.

Next, a method for manufacturing a sealed structure to be performed using the sealing film of the present embodiment will be described. Here, a case where the sealed body, that is, the electronic component is a semiconductor element will be described. FIG. 2 is a schematic cross-sectional view for explaining an embodiment of a method for manufacturing a sealed structure, that is, an embodiment of a method for manufacturing an electronic component device, that is, a semiconductor device. The manufacturing method of this embodiment includes the steps of placing a sealed body (object to be embedded), that is, a plurality of semiconductor elements 20 in parallel on a substrate 30 having a temporary fixing material 40 ((a) of FIG. 2). ); The sealing film 10 with the support body facing the semiconductor element 20 faces backward, and the semiconductor element 20 is embedded in the sealing film by pressing (laminating) the sealing film 2 against the semiconductor element 20 under heating. In 2, the support-attached sealing film 10 includes a support 1 and a sealing film 2 ((b) in FIG. 2) provided on the support 1; and a semiconductor device 20 is embedded therein. The sealing film 2 is hardened to obtain a cured product 2a ((c) of FIG. 2). In this embodiment, after the semiconductor element 20 is sealed with the sealing film 2 according to the lamination method, the sealing film 2 is thermally hardened to obtain a seal including the semiconductor element 20 embedded in the cured material 2a. The structure (electronic component device) can also be obtained by compression molding.

The laminator used for the lamination method is not particularly limited, and examples thereof include a laminator such as a roll type and an air bag type. From the viewpoint of excellent embedding properties, the laminator may be a bladder type capable of performing vacuum pressure.

Lamination is usually carried out below the softening point of the support. The lamination temperature is preferably near the minimum melt viscosity of the sealing film. The pressure at the time of lamination differs according to the size, density, etc. of the to-be-sealed body (for example, an electronic component such as a semiconductor element) to be embedded. The pressure during lamination may be, for example, in a range of 0.2 to 1.5 MPa, or may be in a range of 0.3 to 1.0 MPa. The laminating time is not particularly limited, and may be 20 to 600 seconds, 30 to 300 seconds, or 40 to 120 seconds.

The sealing film can be cured, for example, in the atmosphere or under an inert gas. The curing temperature (heating temperature) is not particularly limited, and may be 80 to 280 ° C, 100 to 240 ° C, or 120 to 200 ° C. When the curing temperature is 80 ° C. or higher, the curing of the sealing film can sufficiently progress, and the occurrence of a defective condition can be suppressed. When the curing temperature is 280 ° C. or lower, there is a tendency that thermal damage to other materials can be suppressed. The curing time (heating time) is not particularly limited, and may be 30 to 600 minutes, 45 to 300 minutes, or 60 to 240 minutes. When the curing time is within these ranges, the curing of the sealing film can sufficiently progress, and more favorable production efficiency can be obtained. Moreover, a plurality of conditions can be combined for the hardening conditions.

Moreover, in this embodiment, a sealed structure, that is, a semiconductor device can be obtained through each of the following steps of forming an insulating layer, forming a line pattern, ball mounting, and cutting.

First, an insulating layer 50 is provided on the exposed side of the semiconductor element 20 of the sealed molded article 100 peeled from the substrate 30 (FIGS. 3 (a) and (b)). Next, after the line pattern is formed on the insulating layer 50, a ball is planted to form the insulating layer 52, the line 54, and the solder ball 56.

Then, the sealing molded article is singulated by the dicing machine 60 to obtain the semiconductor device 200.

As mentioned above, although the preferred embodiment of this invention was described, this invention is not necessarily limited to the said embodiment, A change can be implemented suitably within the range which does not deviate from the meaning. [Example]

Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to these examples at all.

The following materials were used in the examples and comparative examples. (Thermosetting resin) A1: A bisphenol A type epoxy resin containing a flexible skeleton (manufactured by DIC Corporation, trade name "EXA4816", epoxy group equivalent weight: 403 g / eq, liquid ring at 25 ° C Oxygen resin) A2: bisphenol A type epoxy resin containing flexible skeleton (manufactured by DIC Corporation, trade name "EXA4850-1000", epoxy group equivalent weight: 350 g / eq, liquid epoxy resin at 25 ° C Resin) A3: o-cresol novolac epoxy resin (manufactured by DIC Corporation, trade name "N500P-1", epoxy equivalent: 201 g / eq, epoxy resin that is not liquid at 25 ° C) B1 : Hydrocarbon-based phenol resin (phenolic hydroxyl equivalent: 140g / eq) B2: Naphthalene skeleton-containing novolac phenol resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., trade name "SN475N", phenolic hydroxyl equivalent: 205g / eq) B3: Novolac-type phenol resin (produced by Nippon Steel & Sumikin Chemical Co., Ltd. under the trade name "SN395", phenolic hydroxyl equivalent: 110g / eq) (hardening accelerator) C1: imidazole (Shikoku (Product name: "2P4MZ") (Elastomer) D1: Acrylate polymerization (Manufactured by Nagase ChemteX Corporation, trade name "SG-280 EK23", molecular weight 900,000) (inorganic filler) E1: silicon dioxide (manufactured by Admatechs Corporation, trade name "SX-E2", phenylamine Silane treatment, average particle size: 5.8 μm)

In addition, B1 (hydrocarbon-based phenol resin) is a resin composed of a structural unit represented by the following formula (5) at 40 mol% and a structural unit represented by the following formula (6) at 60 mol%.

In this example, B1 was prepared according to the method described in Japanese Patent Application Laid-Open No. 2015-89949. Specifically, first, cardanol, methanol, and a 50% formaldehyde aqueous solution are mixed to obtain a mixed solution. Then, a 30% sodium hydroxide aqueous solution was dropped into the obtained mixed solution to react, and 35% hydrochloric acid was added to the obtained reaction solution to neutralize sodium hydroxide. Then, phenol was added to the reaction solution, and then oxalic acid was further added. Then, after washing the reaction solution with water, excess phenol was distilled off. Thereby, B1 is obtained.

<Preparation of a film for sealing (film-like epoxy resin composition)> (Example 1) 100 g of methyl ethyl ketone (MEK) was put into a polyethylene container, and 18.8 g of A1, 56.3 g of A3, and 45.7 g B1, 12.1 g of D1, and 866.7 g of E1 were added to a 0.5 L (liter) polyethylene container and stirred with a stirring blade to disperse the inorganic filler E1. Then, 0.4 g of the hardener C1 was added, and further stirred for 30 minutes. The obtained mixed liquid was filtered through a nylon # 150 mesh (opening: 106 μm), and the filtrate was extracted. Thereby, a varnish-like epoxy resin composition was obtained. Using a coater, this varnish-like epoxy resin composition was coated on a PET film under the following conditions. Thereby, a sealing film having a thickness of 210 μm was produced on the support.・ Applying head method: corner wheel ・ Coating and drying speed: 0.5 m / min ・ Drying conditions (temperature / furnace length): 80 ° C / 1.5m (meter), 100 ° C / 1.5m ・ Film support Body: PET film with a thickness of 38 μm

A protective layer (a polyethylene terephthalate film having a thickness of 50 μm) is disposed on the side opposite to the support in the sealing film, thereby protecting the surface of the sealing film. In each of the evaluations described below, the evaluation is performed after the support and the protective layer are separated. The same applies to the following examples and comparative examples.

(Examples 2 to 4 and Comparative Examples 1 to 2) The types and blending amounts of the materials (A1, A3, B1, C1, D1, and E1) used were changed as shown in Table 1. Otherwise, it was implemented Example 1 was performed in the same manner to obtain varnish-like epoxy resin compositions of Examples 2 to 4 and Comparative Example 1. Then, the varnish-like epoxy resin composition of Examples 2 to 4 and Comparative Example 1 were used instead of the varnish-like epoxy resin composition of Example 1, and the procedure was performed in the same manner as in Example 1 to obtain The sealing films (thickness: 210 μm) of Examples 2 to 4 and Comparative Example 1. The blending amount of each material in Table 1 is the blending amount (% by mass) based on the total mass of the sealing film.

<Evaluation> The following methods were used to evaluate warpage and cracking of the sealing structure, and the elastic modulus and glass transition temperature of the sealing film after curing. In addition, in the evaluation of the modulus of elasticity and the glass transition temperature of the sealing film after curing, a sealing film having a thickness of 110 μm was used. It is produced under the following conditions.・ Applying head method: corner wheel ・ Coating and drying speed: 1m / min ・ Drying conditions (temperature / furnace length): 80 ° C / 1.5m, 100 ° C / 1.5m ・ Film-shaped support: PET with a thickness of 38μm film

(1) Warpage of the sealing structure The sealing film with a thickness of 210 μm was laminated on a silicon wafer (with a size of 12 inches) having a thickness of 800 μm according to the following conditions to obtain an unhardened sealing structure (epoxy seal body).・ Laminator device: MVLP-500, a vacuum pressure laminator manufactured by Meiki Seisakusho ・ Lamination temperature: 90 ° C ・ Lamination pressure: 0.5MPa ・ Evacuation time: 30 seconds ・ Lamination time: 40 seconds

The obtained uncured sealing structure was cured under the following conditions to obtain a sealed structure (epoxy resin cured body). • Oven: SAFETY OVEN SPH-201 manufactured by ESPEC Corporation. • Oven temperature: 140 ° C. • Time. : 120 minutes

The following apparatus was used to measure the amount of warpage of the obtained sealed structure.・ Warp measurement table device name: CP-500 manufactured by COMS company ・ Warp measurement laser device name: LK-030 manufactured by KEYENCE company

As an index of crackability, warpage after hardening was evaluated according to the following evaluation criteria. A: Amount of warpage ≦ 2.0mm B: Amount of warpage ＞ 2.0mm

(2) The elastic modulus and the glass transition temperature Tg of the sealing film after hardening The sealing films of Examples and Comparative Examples were laminated on a copper foil under the following conditions to obtain a sealing film with a copper foil.・ Laminator device: MVLP-500, a vacuum pressurizing laminator manufactured by Meiji Seisakusho ・ Laminating temperature: 110 ° C ・ Laminating pressure: 0.5MPa ・ Evacuation time: 30 seconds ・ Laminating time: 40 seconds

The sealing film with a copper foil is adhered to a stainless steel (SUS) plate, and the sealing film is hardened under the following conditions to obtain a cured product of the sealing film with a copper foil (epoxy resin with a copper foil). (Hardened body) • Oven: SAFETY OVEN SPH-201 manufactured by ESPEC Corporation • Oven temperature: 140 ° C • Time: 120 minutes

After peeling the copper foil from the hardened | cured material of the sealing film with a copper foil attached, the hardened | cured material of the sealing film was cut into 4 mm x 30 mm, and the test piece was produced. The elastic modulus and glass transition temperature of the produced test piece were measured under the following conditions. • Measuring device: DVE (DVE-V4 manufactured by RHEOLOGY Co., Ltd.) • Measuring temperature: 25 to 300 ° C • Heating rate: 5 ° C / min

When the elastic modulus is high, the sealed structure becomes prone to warping and cracking. Therefore, the elastic modulus is evaluated in accordance with the following judgment criteria. A: Modulus of elasticity (30 ° C) ≦ 25GPa B: Modulus of elasticity (30 ° C) ＞ 25GPa

When the glass transition temperature Tg is low, the thermal reliability of the sealed structure is deteriorated. Therefore, the glass transition temperature is evaluated in accordance with the following judgment criteria. A: Glass transition temperature (℃) ≧ 100 B: Glass transition temperature (℃) ＜ 100

<Evaluation results> The evaluation results are shown in Table 1.

[Table 1]

1‧‧‧ support

2‧‧‧ Sealing film

2a‧‧‧hardened (seal)

10‧‧‧ Sealing film with support

20‧‧‧Semiconductor element (sealed body)

30‧‧‧ substrate

40‧‧‧Temporary fixing material

50, 52‧‧‧ Insulation

54‧‧‧ route

56‧‧‧Solder Ball

60‧‧‧Cutting Machine

100‧‧‧Sealed molding (sealed structure)

200‧‧‧Semiconductor device (sealed structure)

FIG. 1 is a schematic cross-sectional view showing a sealing film with a support, which includes a sealing film according to an embodiment. Fig. 2 is a schematic cross-sectional view for explaining an embodiment of a method for manufacturing a sealed structure. FIG. 3 is a schematic cross-sectional view illustrating an embodiment of a method for manufacturing a sealed structure.

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Claims (16)

A method for producing a sealing film comprising a thermosetting resin and an inorganic filler, the method comprising the steps of preparing a resin composition containing a reactivity as the thermosetting resin; A resin having a functional group equivalent weight greater than 250 g / mol, and the inorganic filler; and a step of forming the resin composition into a thin film. The method for producing a sealing film according to claim 1, wherein a glass transition temperature of the resin composition after curing is 80 to 180 ° C. The method for producing a sealing film according to claim 1 or 2, wherein the resin having a reactive functional group equivalent weight greater than 250 g / mol includes a resin having a reactive functional group equivalent weight of 300 to 410 g / mol. The method for producing a sealing film according to any one of claims 1 to 3, wherein the resin composition further contains a resin having a reactive functional group equivalent of 100 to 210 g / mol as the thermosetting resin. The method for producing a sealing film according to any one of claims 1 to 4, wherein the resin composition further contains, as the thermosetting resin, the following resin: an equivalent to the reactive functional group of more than 250 g / The reactive functional group equivalent of a mol resin is a resin having a reactive functional group equivalent of 1 / 2.9 to 1/2 times. The method for producing a sealing film according to any one of claims 1 to 5, wherein the resin having a reactive functional group equivalent weight greater than 250 g / mol includes an epoxy resin. The manufacturing method of the sealing film as described in any one of Claims 1-6 whose film thickness of the said sealing film is 20-250 micrometers. A sealing film comprising a thermosetting resin and an inorganic filler, and the thermosetting resin contains a resin having a reactive functional group equivalent weight greater than 250 g / mol. The sealing film according to claim 8, wherein the glass transition temperature after curing is 80 to 180 ° C. The sealing film according to claim 8 or 9, wherein the resin having a reactive functional group equivalent weight greater than 250 g / mol includes a resin having a reactive functional group equivalent weight of 300 to 410 g / mol. The sealing film according to any one of claims 8 to 10, wherein the thermosetting resin further contains a resin having a reactive functional group equivalent of 100 to 210 g / mol. The sealing film according to any one of claims 8 to 11, wherein the thermosetting resin further includes a resin having a reactive functional group equivalent to a resin having a reactive functional group equivalent of greater than 250 g / mol. , Resin with a reactive functional group equivalent of 1 / 2.9 to 1/2 times. The sealing film according to any one of claims 8 to 12, wherein the resin having a reactive functional group equivalent weight greater than 250 g / mol includes an epoxy resin. The sealing film according to any one of claims 8 to 13, wherein the film thickness is 20 to 250 μm. A sealed structure comprising: a sealed body; and a cured product of the sealing film according to any one of claims 8 to 14 for sealing the sealed body. A method for manufacturing a sealed structure, comprising the steps of using the sealing film obtained by the method according to any one of claims 1 to 7 or the seal according to any one of claims 8 to 14 A film is used to seal the object to be sealed.