Epoxy resin composition for semiconductor element encapsulation film, semiconductor element encapsulation film, and semiconductor device encapsulated with the same

Abstract

To provide an epoxy resin composition for semiconductor device encapsulating films, that allows neutron shielding, a semiconductor device encapsulating film, and a semiconductor device encapsulated using the same.SOLUTION: An epoxy resin composition for semiconductor device encapsulating films comprises: a liquid epoxy resin; a curing agent; a binder resin; and at least one selected from an oxide, a nitride, a carbide, or a hydroxide including at least one element selected from gadolinium, boron, samarium, cadmium, and europium. The content of the binder resin is 2 to 10 wt.% relative to the total mass of the epoxy resin composition for semiconductor device encapsulating films. The content of the at least one selected from an oxide, a nitride, a carbide, or a hydroxide including at least one element selected from gadolinium, boron, samarium, cadmium, and europium is 50 mass% or more relative to the total mass of the epoxy resin composition for semiconductor device encapsulating films.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an epoxy resin composition for a semiconductor element encapsulation film, a semiconductor element encapsulation film, and a semiconductor device encapsulated with the same, and more particularly to an epoxy resin composition for a semiconductor element encapsulation film capable of shielding neutrons, a semiconductor element encapsulation film, and a semiconductor device encapsulated with the same. [Background technology]

[0002] Cosmic rays are a general term for various high-energy particles and radiation that rain down on Earth from space, and their source is the explosion of celestial bodies within the galaxy.

[0003] Primary cosmic rays that enter the atmosphere collide with nitrogen or oxygen atoms to generate secondary cosmic rays, and it is these secondary and higher cosmic rays that affect the human body and electronic products in everyday life. Of these, excluding protons, which have a small distribution (less than 0.5%), and small particles that have almost no interaction with colliding materials, neutrons account for more than 95% of the causes of semiconductor errors.

[0004] Neutrons are small in size and can pass through most materials, including the human body, but on rare occasions they may collide with other atomic nuclei. The amount of neutron radiation (amount of radiation per unit time) varies depending on altitude, but the number of neutrons at aviation altitudes (10 to 15 km above sea level) is approximately 300 times higher than on the ground.

[0005] Neutrons are small and uncharged, so they can pass through the fuselage of an aircraft, which is made of aluminum and carbon composite materials, and enter the cabin, colliding with silicon (Si) and silicon dioxide (SiO2) nuclei in semiconductor devices during transport, becoming the main cause of total ionizing dose (TID) defects.

[0006] Furthermore, with the advancement of semiconductor manufacturing technology and the resulting miniaturization of structures, the impact of TID defects caused by neutrons on semiconductor devices is gradually increasing. Therefore, there is a need for measures that can effectively prevent TID defects caused by neutrons when transporting semiconductor devices by air. Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide an epoxy resin composition for a semiconductor element encapsulation film capable of shielding neutrons, a semiconductor element encapsulation film, and a semiconductor device encapsulated with the same. [Means for solving the problem]

[0008] 1. According to one aspect of the present invention, there is provided an epoxy resin composition for use in a semiconductor element encapsulation film, the epoxy resin composition for use in a semiconductor element encapsulation film comprising a liquid epoxy resin, a curing agent, a binder resin, and at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium, wherein the content of the binder resin is 2 to 10 mass% based on the total mass of the epoxy resin composition for use in a semiconductor element encapsulation film, and the content of the at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium is 50 mass% or more based on the total mass of the epoxy resin composition for use in a semiconductor element encapsulation film.

[0009] 2. In the above item 1, the liquid epoxy resin may include a bisphenol A type epoxy resin, a hydrogenated bisphenol A type epoxy resin, or a combination thereof.

[0010] 3. In the above 1. or 2., the binder resin may contain an epoxy-modified (meth)acrylic copolymer.

[0011] 4. In any one of the above 1. to 3., at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium is added. 50 ) may be 0.1 to 50 μm.

[0012] 5. In any one of 1. to 4. above, the content of at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium may be 50 to 90 mass%.

[0013] 6. In any one of 1. to 5. above, the composition may contain at least two selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium.

[0014] 7. In any one of the above 1. to 6., the epoxy resin composition for a semiconductor element encapsulation film contains, based on the total mass of the epoxy resin composition for a semiconductor element encapsulation film, 0.5 to 25 mass % of the liquid epoxy resin; 0.1 to 15 mass % of the curing agent; 2 to 10% by mass of the binder resin; and The composition may contain 50 to 90 mass % of at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium.

[0015] 8. According to another aspect of the present invention, there is provided a semiconductor element encapsulation film, which may be obtained by coating a base film or a release film with any one of the epoxy resin compositions for semiconductor element encapsulation films described in 1. to 7. above in a semi-cured state.

[0016] 9. According to yet another aspect of the present invention, there is provided a semiconductor device. The semiconductor device may be encapsulated using the semiconductor element encapsulation film according to 8 above. [Effects of the Invention]

[0017] According to the present invention, there are provided an epoxy resin composition for a semiconductor element sealing film capable of shielding neutrons, a film for sealing a semiconductor element, and a semiconductor device sealed with the same. DETAILED DESCRIPTION OF THE INVENTION

[0018] In this specification, the singular expression includes the plural expression unless the context clearly indicates otherwise.

[0019] In this specification, the terms "comprise" or "have" mean the presence of the features or components described in the specification, but do not preclude the possibility that one or more other features or components may also be added.

[0020] In interpreting elements, unless otherwise expressly stated, it is interpreted as including a margin of error.

[0021] In the present specification, when a numerical range is indicated as "a to b," the "to" is defined as ≧a and ≦b.

[0022] The average particle size (D 50 ) means a normal particle size known to those skilled in the art, and may mean the particle size of particles that make up 50% by volume when particles are distributed in order from smallest to largest by volume.

[0023] An epoxy resin composition for a semiconductor element encapsulation film according to one embodiment of the present invention includes a liquid epoxy resin; a curing agent; a binder resin; and at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium. The content of the binder resin is 2 to 10% by mass based on the total mass of the epoxy resin composition for a semiconductor element encapsulation film, and the content of the at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium is 50% by mass or more based on the total mass of the epoxy resin composition for a semiconductor element encapsulation film.

[0024] Hereinafter, each of the constituent components of the epoxy resin composition for semiconductor element encapsulation film (hereinafter also simply referred to as "epoxy resin composition") will be described in more detail.

[0025] (liquid epoxy resin) Liquid epoxy resins can impart superior adhesive strength to films during film formation compared to solid epoxy resins.

[0026] Liquid epoxy resins commonly used for semiconductor device encapsulation can be used without limitation. Specifically, liquid epoxy resins may be epoxy compounds containing two or more epoxy groups per molecule. Examples of liquid epoxy resins include bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, bisphenol AD-type epoxy resins, bisphenol S-type epoxy resins, fluorene-type epoxy resins, naphthalene-type epoxy resins, biphenyl-type epoxy resins, glycidylamine-type epoxy resins, alicyclic epoxy resins (e.g., hydrogenated bisphenol A-type epoxy resins), dicyclopentadiene-type epoxy resins, polyether-type epoxy resins, and silicone-modified epoxy resins. These may be used alone or in combination. According to one embodiment, the liquid epoxy resin may be bisphenol A-type epoxy resin and / or hydrogenated bisphenol A-type epoxy resin. In this case, the high hydrogen content of these resins may enhance neutron shielding properties due to the neutron scattering effect, but the liquid epoxy resin is not limited thereto.

[0027] In consideration of curability, the epoxy resin is preferably an epoxy resin having an epoxy equivalent of 100 to 500 g / eq. If the epoxy equivalent is within the above range, the degree of curing can be increased, but is not limited thereto.

[0028] The amount (content) of the liquid epoxy resin used is not particularly limited, but is preferably 0.5 to 25 mass% based on the total mass of the epoxy resin composition. Within this range, the curability of the composition is less likely to decrease. According to one embodiment, the content of the epoxy resin is more preferably 3 to 15 mass% based on the total mass of the epoxy resin composition, but is not limited thereto.

[0029] (hardening agent) The curing agent may be any curing agent commonly used for semiconductor element encapsulation, and is not particularly limited. For example, an acid anhydride curing agent, a phenolic curing agent, an amine curing agent, or an imidazole curing agent may be used. Examples of the acid anhydride curing agent include phthalic anhydride, hexahydrophthalic anhydride, alkylhexahydrophthalic anhydride (e.g., 4-methylhexahydrophthalic anhydride), alkyltetrahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride, succinic anhydride, methylnadic anhydride, trimellitic anhydride, pyrometic anhydride, and methylnorbornene-2,3-dicarboxylic acid. Examples of phenolic curing agents include phenol aralkyl phenolic resins, phenol novolac phenolic resins, multifunctional phenolic resins, xylok phenolic resins, cresol novolac phenolic resins, naphthol phenolic resins, terpene phenolic resins, dicyclopentadiene phenolic resins, novolac phenolic resins synthesized from bisphenol A and resol, and polyhydric phenolic compounds containing tris(hydroxyphenyl)methane and dihydroxybiphenyl. Examples of amine curing agents include melamine, metaphenylenediamine, dimethylaniline, diaminodiphenylmethane, and diaminodiphenyl sulfone. Examples of imidazole curing agents include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, and epoxy-imidazole adducts. These can be used alone or in combination. According to one embodiment, the curing agent is preferably an amine-based curing agent and / or an imidazole-based curing agent having a high hydrogen content, examples of which include, but are not limited to, melamine, diaminodiphenylmethane, and 2-methylimidazole.

[0030] The amount (content) of the curing agent used is not particularly limited, but is preferably 0.1 to 15 mass% based on the total mass of the epoxy resin composition. Within this range, the curing properties of the composition are less likely to deteriorate. According to one embodiment, the content of the curing agent is more preferably 1 to 10 mass% based on the total mass of the epoxy resin composition, but is not limited thereto.

[0031] The compounding ratio of the epoxy resin to the curing agent may vary depending on the required conditions of the package, such as mechanical properties and moisture resistance reliability. For example, the chemical equivalent ratio of the epoxy resin to the curing agent is preferably 0.95 to 3. Within this range, excellent strength can be achieved after curing of the epoxy resin composition, but the present invention is not limited to this. According to one embodiment, the chemical equivalent ratio of the epoxy resin to the curing agent may be 1 to 2, and according to another embodiment, it may be 1 to 1.75.

[0032] (binder resin) The binder resin can have the function of improving the brittle nature of the cured system, increasing fracture toughness, and relieving internal stress.

[0033] Conventional binder resins can be used without limitation as the binder resin. Examples of binder resins include epoxy-modified urethane copolymers, epoxy-modified (meth)acrylic copolymers, polyester-based polymer resins (e.g., polyester polyols), epoxy resin-diluted acrylic rubber (acrylic rubber dispersed in epoxy resins), core-shell rubber, acrylonitrile-butadiene rubber (NBR), carboxy-terminated butadiene nitrile (CTBN), acrylonitrile-butadiene-styrene copolymers, and polymethyl siloxane. These can be used alone or in combination. According to one embodiment, it is preferable to use an epoxy-modified (meth)acrylic copolymer as the binder resin. In this case, the cured composition layer is provided with flexibility, and the high hydrogen content thereof can provide additional neutron scattering effects. However, the binder resin is not limited thereto.

[0034] The binder resin is preferably contained in an amount of 2 to 10% by mass (e.g., 2, 3, 4, 5, 6, 7, 8, 9, or 10% by mass) based on the total mass of the epoxy resin composition. This range provides excellent film-forming ability (wettability and leveling), excellent heat resistance due to the high crosslink density of the curing components, and excellent neutron shielding ability due to the inclusion of a sufficient amount of at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium. The binder resin content may be, for example, 2 to 8% by mass, or, for example, 2 to 6% by mass, based on the total mass of the epoxy resin composition, but is not limited thereto.

[0035] (At least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium) At least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium, i.e., gadolinium oxide, gadolinium nitride, gadolinium carbide, gadolinium hydroxide, boron oxide, boron nitride, boron carbide, boron hydroxide, samarium oxide, samarium nitride, samarium carbide, samarium hydroxide, cadmium oxide, cadmium nitride, cadmium carbide, cadmium hydroxide, europium oxide, europium nitride, europium carbide, and / or europium hydroxide, has a large neutron absorption cross section. Therefore, when a semiconductor device is encapsulated using a semiconductor element encapsulation film containing these, neutron shielding through neutron absorption at the semiconductor package level is possible.

[0036] The content of at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium is 50% by mass or more based on the total mass of the epoxy resin composition. If the content is less than 50% by mass, a predetermined neutron shielding efficiency cannot be achieved. The content of at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium is, for example, 50 to 90% by mass (for example, 50% by mass, 51% by mass, 52% by mass, 53% by mass, 54% by mass, 55% by mass, 56% by mass, 57% by mass, 58% by mass, 59% by mass, 60% by mass, 61% by mass, 62% by mass, 63% by mass, 64% by mass, 65% by mass, 66% by mass, 67% by mass, 68% by mass, 69% by mass, 70% by mass, 71% by mass, 72% by mass, 73% by mass, 74% by mass, 75% by mass, 76% by mass, 77% by mass, 78% by mass, 79% by mass, 80% by mass, 81% by mass, 82% by mass, 83% by mass, 84% by mass, 85% by mass, 86% by mass, 87% by mass, 88% by mass, 89% by mass, 89% by mass, 90% by mass, 91% by mass, 92% by mass, 93% by mass, 94% by mass, 95% by mass, 9 The content may be 3% by weight, 64% by weight, 65% by weight, 66% by weight, 67% by weight, 68% by weight, 69% by weight, 70% by weight, 71% by weight, 72% by weight, 73% by weight, 74% by weight, 75% by weight, 76% by weight, 77% by weight, 78% by weight, 79% by weight, 80% by weight, 81% by weight, 82% by weight, 83% by weight, 84% by weight, 85% by weight, 86% by weight, 87% by weight, 88% by weight, 89% by weight, or 90% by weight, or for other examples, 60 to 88% by weight, or for further examples, 80 to 87% by weight. This range may achieve a high neutron shielding efficiency, ensure the flexibility of the film, reduce the possibility of cracking during the bonding process, and facilitate obtaining the film form, but is not limited thereto.

[0037] The shape of the at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium is not particularly limited, and particles of various shapes, such as spherical, plate-like, or amorphous particles, can be used.

[0038] The size of at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium is not particularly limited and may vary depending on the required physical properties. For example, the average particle size (D 50 ) is 0.1 to 50 μm (for example, 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm, 30 μm, 31 μm, 32 μm, 33 μm, 34 μm, 35 μm, 36 μm, 37 μm, 38 μm, 39 μm, 40 μm, 41 μm, 42 μm, 43 μm, 44 μm, 45 μm, 46 μm, 47 μm, 48 μm, 49 μm, 50 μm, 51 μm, 52 μm, 53 μm, 54 μm, 55 μm, 56 μm, 57 μm, 58 μm, 59 μm, 60 μm, 61 μm, 62 μm, 63 μm, 64 μm, 65 μm, 66 μm, 67 μm, 68 μm, 69 μm, 70 μm, 71 μm, 72 μm, 73 μm, 7 The average particle diameter (D) of the adhesive may be, for example, 0.6 μm, 27 μm, 28 μm, 29 μm, 30 μm, 31 μm, 32 μm, 33 μm, 34 μm, 35 μm, 36 μm, 37 μm, 38 μm, 39 μm, 40 μm, 41 μm, 42 μm, 43 μm, 44 μm, 45 μm, 46 μm, 47 μm, 48 μm, 49 μm, or 50 μm, or, for example, 0.5 to 25 μm, or, for example, 1.0 to 12 μm. Within this range, there is almost no risk of a decrease in adhesive strength due to an increase in melt viscosity at the adhesive temperature, and the adhesive has an excellent filling factor, which can result in an excellent neutron shielding efficiency, but the range is not limited thereto. In addition, the average particle diameter (D) of the adhesive may be different from each other. 50 At least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium, each having an average particle size (D 50At least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium, having an average particle size (D 50 and at least one selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium, the particle size of which is 0.1 to 3 μm, may be mixed in a predetermined compounding ratio and used, and in this case, the filling rate can be further improved.

[0039] According to one embodiment, the epoxy resin composition according to the present invention may contain at least two selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium. Since each of these compounds has a different energy range in which it can absorb neutrons, when two or more of these compounds are contained, the neutron absorption range is broadened, and the neutron shielding properties can be further improved.

[0040] (curing accelerator) The epoxy resin composition according to the present invention may further contain a curing accelerator.

[0041] Curing accelerators are substances that accelerate the reaction between epoxy resins and curing agents. Examples of curing accelerators include tertiary amines, organometallic compounds, organophosphorus compounds, imidazole compounds, and boron compounds.

[0042] Tertiary amines include, for example, benzyldimethylamine, triethanolamine, triethylenediamine, diethylaminoethanol, tri(dimethylaminomethyl)phenol, 2-2-(dimethylaminomethyl)phenol, 2,4,6-tris(diaminomethyl)phenol, and tri-2-ethylhexanoate. Organometallic compounds include chromium acetylacetonate, zinc acetylacetonate, and nickel acetylacetonate. Organophosphorus compounds include tris-4-methoxyphosphine, tetrabutylphosphonium bromide, tetraphenylphosphonium bromide, phenylphosphine, diphenylphosphine, triphenylphosphine, triphenylphosphinetriphenylborane, and triphenylphosphine-1,4-benzoquinone adduct. Examples of imidazole compounds include 2-phenyl-4-methylimidazole, 2-methylimidazole, 2-phenylimidazole, 2-aminoimidazole, 2-methyl-1-vinylimidazole, 2-ethyl-4-methylimidazole, 2-heptadecylimidazole, etc. Examples of boron compounds include tetraphenylphosphonium-tetraphenylborate, triphenylphosphine tetraphenylborate, tetraphenylboron salt, trifluoroborane-n-hexylamine, trifluoroborane monoethylamine, tetrafluoroborane triethylamine, tetrafluoroborane amine, etc. Other examples of curing accelerators include, but are not limited to, 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), and phenol novolac resin salts.

[0043] As the curing accelerator, an adduct prepared by pre-reacting an epoxy resin or a curing agent with a curing accelerator can also be used.

[0044] The amount (content) of the curing accelerator used is not particularly limited, but is preferably 0.01 to 2 mass% based on the total mass of the epoxy resin composition. Within this range, the curing of the composition can be accelerated and the degree of curing can be improved. According to one embodiment, the content of the curing accelerator is more preferably 0.02 to 1.5 mass% based on the total mass of the epoxy resin composition, but is not limited thereto.

[0045] The epoxy resin composition of the present invention may further contain one or more of a coupling agent and a mold release agent.

[0046] (coupling agent) The coupling agent reacts between the epoxy resin and the inorganic filler to improve the interfacial strength, and an example of the coupling agent is a silane coupling agent. The silane coupling agent may be any agent that reacts between the epoxy resin and the inorganic filler to improve the interfacial strength between the epoxy resin and the inorganic filler, and the type is not particularly limited. Examples of the silane coupling agent include epoxy silane, amino silane, ureido silane, mercapto silane, and alkyl silane. The coupling agent may be used alone or in combination of two or more.

[0047] The amount (content) of the coupling agent used is not particularly limited, but is preferably, for example, 0.01 to 5 mass% based on the total mass of the epoxy resin composition. Within this range, the strength of the cured product of the composition can be improved. According to one embodiment, the content of the coupling agent is more preferably, but not limited to, 0.05 to 3 mass% based on the total mass of the epoxy resin composition.

[0048] (mold release agent) As the release agent, at least one selected from the group consisting of paraffin wax, ester wax, higher fatty acid, higher fatty acid metal salt, natural fatty acid, and natural fatty acid metal salt may be used.

[0049] The amount (content) of the release agent used is not particularly limited, but is preferably, for example, 0.01 to 1% by mass based on the total mass of the epoxy resin composition for semiconductor element encapsulation.

[0050] In addition, the epoxy resin composition may further contain, as necessary, antioxidants such as tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane; flame retardants such as aluminum hydroxide, and the like, within the scope of the present invention.

[0051] The epoxy resin composition described above can be prepared in the form of a semiconductor element encapsulation film and applied to semiconductor elements. Such a semiconductor element encapsulation film can be prepared, for example, by dissolving the epoxy resin composition in an organic solvent, applying the resulting varnish to a substrate film, and then removing volatile components from the varnish by heating and aging / drying to form a composition layer. Organic solvents can be used to easily obtain a blend of various components in the varnish preparation process. Examples of organic solvents include ketones such as acetone, methyl ethyl ketone, and cyclohexanone; acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, and propylene glycol monomethyl ether acetate; and aromatic hydrocarbons such as toluene and xylene. These organic solvents can be used alone or in combination. Materials for the substrate film include, but are not limited to, polyester, polyimide, polyamide, polyethersulfone, polyphenylene sulfide, polyetherketone, polyetheretherketone, polyacetylcellulose, polyetheramide, polyethylene naphthalate, polypropylene, and polycarbonate. According to one embodiment, a release film having releasability may be used as the substrate film, and such release film may be selected from, but is not limited to, polyolefins such as polyethylene, polyvinyl chloride, and polypropylene; polyesters such as polyethylene terephthalate; and release paper. The method for applying the varnish to the substrate film may be appropriately selected from coating methods known in the art, such as roll coating, gravure coating, microgravure coating, bar coating, and knife coating.

[0052] According to another aspect of the present invention, there is provided a film for encapsulating semiconductor elements, in which the above-mentioned epoxy resin composition is coated in a semi-cured state on a base film (e.g., a base film that has been subjected to a release treatment) or a release film.

[0053] When an epoxy resin composition is prepared in the form of a film, it can be used in semiconductor device packaging (e.g., panel level packaging (PLP)) where individual chips are packaged without being cut out. The film can be laminated onto the chip and then fully cured to encapsulate the semiconductor, which can offer the advantage of encapsulating semiconductor devices over a larger area in a simpler manner. The release-treated substrate film or release film can be removed immediately after lamination, during the curing process, or after the curing process.

[0054] The thickness of the base film or release film can be appropriately selected taking into consideration the semiconductor device packaging conditions, etc. For example, the thickness of the base film or release film may be 10 to 90 μm, e.g., 25 to 75 μm, but is not limited to these.

[0055] The thickness of the coated epoxy resin composition can be appropriately selected taking into consideration the packaging conditions of semiconductor devices, etc. For example, the thickness of the coated epoxy resin composition may be 5 to 150 μm, e.g., 15 to 120 μm, but is not limited thereto.

[0056] The method for producing a semiconductor element encapsulation film is not particularly limited. For example, the film can be produced by coating a coating liquid containing the above-described epoxy resin composition on a substrate film (e.g., a substrate film treated with a release agent) or a release film, followed by drying and semi-curing. The drying and semi-curing conditions are not particularly limited. For example, drying may be performed at a temperature of 70 to 90°C for 1 to 15 minutes, and semi-curing may be performed at a temperature of 100 to 150°C for 1 to 10 minutes. The coating liquid can be produced by dissolving or dispersing the above-described epoxy resin composition in an appropriate solvent, such as propylene glycol methyl ether acetate (PGMEA), 2-butanone, methyl ethyl ketone (MEK), acetone, toluene, dimethylformamide (DMF), methyl cellosolve (MCS), tetrahydrofuran (THF), N-methylpyrrolidone (NMP), or propylene glycol methyl ether (PGME). As the coating method, known methods such as screen printing, knife coating, roll coating, spray coating, gravure coating, curtain coating, comma coating, and lip coating can be used without any restrictions.

[0057] According to another aspect of the present invention, there is disclosed a semiconductor device encapsulated using the semiconductor element encapsulation film described above. The method for encapsulating the semiconductor element can be, but is not limited to, a compression molding method, a lamination method, or a combination thereof. [Example]

[0058] The present invention will be described in more detail below with reference to examples, but these are presented as preferred examples of the present invention and should not be construed as limiting the present invention in any way.

[0059] The specific specifications of the components used in the following examples and comparative examples are as follows:

[0060] (A) Liquid epoxy resin (a1) KDS-8128, manufactured by Kokuto Chemical Co., Ltd. (a2) EP-4080E, manufactured by ADEKA Corporation (a3) RE-304S, manufactured by Nippon Kayaku Co., Ltd. (B) Solid epoxy resin (b1) NC-3000, manufactured by Nippon Kayaku Co., Ltd. (b2) XD-1000H, manufactured by Nippon Kayaku Co., Ltd. (C) Hardener (c1) HF-3M, manufactured by Meiwa Sangyo Co., Ltd. (c2) Melamine, manufactured by Sigma-Aldrich (c3) 4,4'-diaminodiphenylmethane, manufactured by Sigma-Aldrich (D) Binder resin: epoxy-modified acrylic copolymer (KG-8070, manufactured by Negami Chemical Industrial Co., Ltd., Japan) (E) Spherical gadolinium oxide, D 50 2.9μm, sieving size:10μm (F) Spherical boron carbide, D 50 4.6μm, sieving size:20μm (G) Spherical silica, D 50 0.58μm, sieving size:5μm (H) Curing accelerator: (h1) TPP-k (registered trademark), manufactured by Hokko Chemical Industry Co., Ltd. (h2) 2-Methylimidazole, manufactured by Sigma-Aldrich (h3) 4-Pyrrolidinopyridine, manufactured by Sigma-Aldrich (I) Coupling agent: A-187, manufactured by Momentive (Examples 1 to 18 and Comparative Examples 1 to 4) An epoxy resin composition for semiconductor element encapsulation film, which is a mixture of the components shown in Tables 1 and 2 below, and an organic solvent (a mixture of methyl ethyl ketone and propylene glycol methyl ether acetate in a volume ratio of 2:1) were mixed to prepare a varnish with a solid content of 70%. This varnish was then coated onto a release film (RPK-201, thickness: 38 μm, manufactured by Toray Advanced Materials Co., Ltd.) to a thickness of 120 μm, and dried in a convection oven at 80°C for 7 minutes and at 125°C for 3 minutes to prepare a semi-cured (B-stage) semiconductor element encapsulation film with a residual solvent content of 0.5 mass% or less.

[0061] In Tables 1 and 2 below, "-" indicates that the component is not used.

[0062] [Table 1]

[0063] [Table 2]

[0064] The films for encapsulating semiconductor elements produced in the above Examples and Comparative Examples were evaluated for the physical properties shown in Tables 3 and 4 below.

[0065] (1) Film forming properties (wettability): Immediately after coating and semi-curing, defects such as pinholes, craters, and blisters were visually checked.

[0066] (2) Neutron shielding rate (unit: %): Three semi-cured semiconductor element encapsulation films manufactured in the examples and comparative examples were prepared. Two of the films were arranged so that their resin layers were in contact with each other, and then they were bonded together using a laboratory laminator. The release film was then removed. Another semiconductor element encapsulation film was then placed on top of the film so that their resin layers were in contact with each other, and then they were bonded together using the laboratory laminator. The release film was then removed to form a film with a total thickness of 360 μm. This was cured at 180°C for 90 minutes to obtain a final cured product sample. The neutron shielding rate of the obtained sample was evaluated under the following conditions using neutron activation analysis, which measures and analyzes the radiation dose of radioactive isotopes generated by neutron reactions.

[0067] *Neutron source: 5W-class research reactor * Energy level of incident neutrons: 0 to 10 MeV (neutrons below 1 eV: neutrons above 10 MeV = 4:1) *Neutron irradiation amount (neutron / cm 2 sec):7.8×10 8 .

[0068] (3)adhesion 1. Minimum melt viscosity (unit: Pa s): For the semi-cured semiconductor element encapsulation films produced in the examples and comparative examples, the melt viscosity was measured in the range of 30 to 200°C at a heating rate of 10°C / min, strain of 5%, and frequency of 1 rad / s using a parallel plate and an aluminum disposable plate (diameter 8 mm) (ARES G2, TA Instruments). The minimum melt viscosity was recorded in the range of 30 to 200°C.

[0069] 2. Peel strength (unit: gf / cm): The semi-cured semiconductor element encapsulation films prepared in the examples and comparative examples were placed on a copper clad laminate with the resin layer abutting, and bonded using a laboratory laminator (110°C x 1 m / min), after which the release film was removed. Subsequently, the film was cured at 180°C for 90 minutes to obtain a cured sample. The resulting sample was peeled at a 90° angle using a universal testing machine (UTM) to measure the peel strength.

[0070] (4) Thermal reliability 1. TGA (thermogravimetric analysis, unit: %): The semi-cured semiconductor element encapsulation films prepared in the examples and comparative examples were subjected to a primary cure at 110°C for 30 minutes, after which the release film was removed. Subsequently, the films were further cured at 180°C for 60 minutes to obtain cured samples. The cured samples thus obtained were heated in a nitrogen atmosphere from 25°C to 800°C at a heating rate of 10 K / min, and the weight loss (%) occurring at 300°C was recorded as data.

[0071] 2. Solder immersion (limit temperature measurement): The semi-cured semiconductor element encapsulation films prepared in the examples and comparative examples were placed on a copper clad laminate with the resin layer facing up, and then bonded using a laboratory laminator (110°C x 1 m / min). The release film was then removed. The films were then cured at 180°C for 90 minutes to obtain cured samples. The resulting cured samples were immersed in a solder pot for 1 minute, increasing the temperature by 10°C from 220°C. If voids or delamination occurred between the copper clad laminate and the cured product, the sample was deemed unable to withstand the temperature. The highest temperature that could be tolerated was determined as the limit temperature (unit: °C).

[0072] (5) Breakdown voltage (unit: kV / mm): The semi-cured semiconductor element encapsulation films produced in the examples and comparative examples were subjected to a primary cure at 110°C for 30 minutes, after which the release film was removed. Subsequently, the films were further cured at 180°C for 60 minutes to obtain cured samples. An AC voltage was applied to the cured samples, and the breakdown voltage was measured at room temperature (25°C) according to ASTM-D149.

[0073] [Table 3]

[0074] [Table 4]

[0075] As is clear from Tables 3 and 4 above, the semiconductor element encapsulation films of Examples 1 to 18 prepared from the epoxy resin compositions of the present invention exhibited high neutron shielding efficiency, peel strengths of 350 gf / cm or more, and critical heat resistance temperatures of 250°C or more, demonstrating excellent adhesive strength and heat resistance. On the other hand, Comparative Example 1, which did not contain at least one element selected from the group consisting of oxides, nitrides, carbides, and hydroxides containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium, exhibited a decreased neutron shielding efficiency. Furthermore, Comparative Example 2, in which the binder resin content was below the range of the present invention, exhibited poor wettability, resulting in defects in the formed film and making it unsuitable for use as a semiconductor element encapsulation film. Furthermore, Comparative Example 3, in which the binder resin content exceeded the range of the present invention, and Comparative Example 4, in which a solid epoxy resin rather than a liquid epoxy resin was used, exhibited decreased adhesive strength.

[0076] The present invention has been described above with reference to the preferred embodiments. Those skilled in the art will recognize that the present invention can be embodied in various modified forms without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered from an illustrative rather than a restrictive perspective. The scope of the present invention is defined by the claims, not the above description, and all variations within the scope of the claims should be construed as being within the scope of the present invention.

Claims

1. Liquid epoxy resin; hardener; a binder resin; and at least one selected from the group consisting of gadolinium oxide and boron carbide; An epoxy resin composition for a semiconductor element encapsulating film, comprising: the binder resin contains an epoxy-modified (meth)acrylic copolymer, The epoxy resin composition for a semiconductor element encapsulation film contains, based on the total mass of the epoxy resin composition for a semiconductor element encapsulation film, 0.5 to 25 mass% of the liquid epoxy resin; 0.1 to 15% by mass of the curing agent; 2 to 10% by mass of the binder resin; and an epoxy resin composition for semiconductor element encapsulation films, comprising: 50 to 90 mass % of at least one selected from the group consisting of gadolinium oxide and boron carbide.

2. 2. The epoxy resin composition for semiconductor element encapsulation films according to claim 1, wherein the liquid epoxy resin comprises a bisphenol A type epoxy resin, a hydrogenated bisphenol A type epoxy resin, or a combination thereof.

3. The average particle size (D ５０ 3. The epoxy resin composition for semiconductor element encapsulation films according to claim 1, wherein the thickness of the epoxy resin composition is 0.1 to 50 μm.

4. 4. The epoxy resin composition for a semiconductor element encapsulation film according to claim 1, wherein the epoxy resin composition for a semiconductor element encapsulation film contains the gadolinium oxide and the boron carbide.

5. A semiconductor element encapsulation film, comprising a substrate film or a release film coated with the epoxy resin composition for semiconductor element encapsulation film according to any one of claims 1 to 4 in a semi-cured state.

6. A semiconductor device encapsulated with the semiconductor element encapsulating film according to claim 5.

Images