Epoxy resin composition for sealing multi-chip package and semiconductor device sealed using the same

Abstract

To provide an epoxy resin composition for sealing a multi-chip package semiconductor device, the composition being capable of suppressing generation of voids at the time of molding a multi-chip package.SOLUTION: An epoxy resin composition for sealing a multi-chip package comprises an epoxy resin, a curing agent, an inorganic filler, a curing catalyst, and a first additive, wherein the first additive includes zinc cyanurate. The epoxy resin composition for sealing a multi-chip package of the present invention is capable of preventing occurrence of cracks in a multi-chip package by suppressing generation of voids at the time of molding of the multi-chip package, thereby improving moldability and reliability.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an epoxy resin composition for sealing a multi-chip package and a semiconductor device sealed with the same. [Background technology]

[0002] In recent years, the integration level of semiconductor elements has been increasing day by day, resulting in the rapid advancement of finer wiring, larger elements, and multi-layer wiring.Packages that protect semiconductor elements from the external environment are becoming increasingly smaller and thinner in order to allow for high-density mounting on printed circuit boards, i.e., surface mounting.

[0003] In resin-encapsulated semiconductor devices, in which large semiconductor elements are encapsulated in small, thin packages, thermal stress caused by changes in the temperature and humidity of the external environment can cause package cracks, aluminum pad corrosion, and other failures at a very high frequency. As a solution to package cracks, improving the reliability of epoxy resin molding materials for encapsulation is gaining momentum.

[0004] In recent years, multichip packages, which vertically stack multiple semiconductor chips, have been gaining attention as part of efforts to make semiconductor devices smaller, thinner, and more powerful. In multichip packages, each chip is attached using a die attach film (DAF). This may present a significant vulnerability in terms of reliability compared to the existing method of attaching a single semiconductor chip to a metal pad using a metal paste, a type of chip adhesive. Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide an epoxy resin composition for sealing a multi-chip packaged semiconductor device, which can suppress the generation of voids during molding of the multi-chip package. [Means for solving the problem]

[0006] According to one embodiment, an epoxy resin composition for sealing a multi-chip package is provided.

[0007] The epoxy resin composition for sealing a multi-chip package includes an epoxy resin, a curing agent, an inorganic filler, a curing catalyst, and a first additive, and the first additive includes zinc cyanurate.

[0008] According to one embodiment, a multi-chip package is provided.

[0009] The multi-chip package is sealed with the epoxy resin composition for sealing the multi-chip package. [Effects of the Invention]

[0010] The epoxy resin composition for sealing a multi-chip package of the present invention can prevent the occurrence of cracks in a multi-chip package by suppressing the occurrence of voids during molding of the multi-chip package, thereby improving moldability and reliability. DETAILED DESCRIPTION OF THE INVENTION

[0011] Although the present invention may be embodied in many different forms, it is not intended to be limited to the embodiments set forth herein.

[0012] The terms used herein are merely used to describe exemplary embodiments and are not intended to limit the present invention. The singular expressions include the plural expressions unless the context clearly indicates otherwise.

[0013] In this specification, when describing a range of values, "X to Y" means X or more and Y or less.

[0014] According to one embodiment, an epoxy resin composition for sealing a multi-chip package includes an epoxy resin, a curing agent, an inorganic filler, a curing catalyst, and a first additive, and the first additive includes zinc cyanurate.

[0015] Epoxy resin The epoxy resin may include one or more epoxy resins having two or more epoxy groups in the molecule. For example, the epoxy resin may be a bisphenol A epoxy resin, a bisphenol F epoxy resin, a phenol novolac epoxy resin, a tert-butylcatechol epoxy resin, a naphthalene epoxy resin, a glycidylamine epoxy resin, a cresol novolac epoxy resin, a biphenyl epoxy resin, a phenol aralkyl epoxy resin, a linear aliphatic epoxy resin, an alicyclic epoxy resin, a heterocyclic epoxy resin, a spiro ring-containing epoxy resin, a cyclohexanedimethanol epoxy resin, a trimethylol epoxy resin, or a halogenated epoxy resin including a brominated epoxy resin. Two or more of the epoxy resins may be mixed together.

[0016] For example, the epoxy resin may include one or more of a biphenyl-type epoxy resin, a phenol aralkyl-type epoxy resin, and a halogenated epoxy resin. For example, the epoxy resin may be a mixture of a biphenyl-type epoxy resin, a phenol aralkyl-type epoxy resin, and a halogenated epoxy resin.

[0017] For example, the biphenyl-type epoxy resin may be represented by the following Chemical Formula 1:

[0018] [ka] (chemical formula 1) (In the above Chemical Formula 1, the average value of n is 1 to 7).

[0019] For example, the phenol aralkyl epoxy resin may be represented by the following Chemical Formula 2:

[0020] [ka] (Chemical formula 2) (In the above Chemical Formula 2, the average value of n is 1 to 7).

[0021] For example, the epoxy resin may contain a biphenyl-type epoxy resin in an amount of 40 wt % or more, e.g., 45 wt % or more, based on the total weight of the epoxy resin. The biphenyl-type epoxy resin may be contained alone in the composition, or may be contained in the form of an addition compound obtained by adding a portion of the compound.

[0022] The epoxy resin may be contained in the epoxy resin composition in an amount of 2 to 17% by weight, for example, 3 to 15% by weight, 2 to 10% by weight, or 3 to 12% by weight, such that the curability of the composition is not reduced.

[0023] hardener Examples of curing agents include novolac phenolic resins, cresol novolac phenolic resins, multifunctional phenolic resins, phenol aralkyl phenolic resins, phenol novolac phenolic resins, Xyloc phenolic resins, cresol novolac phenolic resins, naphthol phenolic resins, terpene phenolic resins, dicyclopentadiene-based phenolic resins, and novolac phenolic resins synthesized from bisphenol A and resol; polyhydric phenol compounds including tris(hydroxyphenyl)methane and dihydroxybiphenyl; acid anhydrides including maleic anhydride and phthalic anhydride; and aromatic amines such as metaphenylenediamine, diaminodiphenylmethane, and diaminodiphenylsulfone. Two or more of the curing agents may be mixed together.

[0024] For example, a phenol-based curing agent may be used as the curing agent in order to improve moldability, moisture resistance, heat resistance, and storage stability when molding a semiconductor.

[0025] For example, the curing agent may include one or more of a Zylok-type phenolic resin, a phenol aralkyl-type phenolic resin, and a phenol novolac-type phenolic resin, or may be a mixture of three types of a Zylok-type phenolic resin, a phenol aralkyl-type phenolic resin, and a phenol novolac-type phenolic resin.

[0026] For example, the Zylok-type phenolic resin can be represented by the following chemical formula 3:

[0027] [ka] (Chemical formula 3) (In the above formula 3, the average value of n is 1 to 7).

[0028] For example, the phenol aralkyl phenolic resin can be represented by the following Chemical Formula 4:

[0029] [ka] (Chemical formula 4) (In the above Chemical Formula 4, the average value of n is 1 to 7).

[0030] For example, the curing agent may contain 20% by weight or more, particularly 25% by weight or more, of a phenol aralkyl type phenolic resin in the total curing agent.

[0031] The curing agent may be included in the epoxy resin composition in an amount of 0.1 to 13% by weight, for example, 0.1 to 10% by weight, or 0.5 to 7% by weight, such that the curing property of the composition is not reduced.

[0032] The ratio of epoxy resin to hardener may preferably be in the range of 0.5 to 1.5, particularly 0.8 to 1.2, in terms of chemical equivalents, depending on the required mechanical properties and moisture resistance reliability.

[0033] inorganic fillers The inorganic filler can improve the mechanical properties of the epoxy resin composition and can further reduce stress.

[0034] The inorganic filler may include one or more of fused silica, crystalline silica, calcium carbonate, magnesium carbonate, alumina, magnesia, clay, talc, calcium silicate, titanium oxide, antimony oxide, and glass fiber.

[0035] Preferably, the inorganic filler may include silica.

[0036] The silica may include one or more of fused silica and crystalline silica. The silica may include fused silica, which has a low linear expansion coefficient for reducing stress. Fused silica refers to amorphous silica having a true specific gravity of 2.3 or less, and may include amorphous silica produced by melting crystalline silica or synthesized from various raw materials. The shape and particle size of the silica are not particularly limited, but the average particle size (D 50 It is preferable to include spherical fused silica having an average particle size (D) of 5 μm to 30 μm in the total inorganic filler so that the amount is 40% by weight to 100% by weight. For example, the silica has an average particle size (D 50 50% to 99% by weight of spherical silica having an average particle size (D 50 The silica may be a silica mixture containing 1% to 50% by weight of spherical silica having an average particle size (D) of 0.001 μm to 1 μm. In addition, the silica may be used with its maximum particle size adjusted to any one of 45 μm, 55 μm, and 75 μm depending on the application. 50)" means a normal particle size known to those of ordinary skill in the art, and may mean the particle size of the inorganic filler that corresponds to 50% by volume when the inorganic fillers are distributed in order from smallest to largest on a volume basis.

[0037] The inorganic filler may contain the silica in an amount of 40% by weight or more, for example, 60% by weight or more, based on the total weight of the inorganic filler.

[0038] The amount of inorganic filler used varies depending on the required physical properties, such as thermal conductivity, moldability, low stress, and high-temperature strength. In a specific example, the inorganic filler may be included in the epoxy resin composition in an amount of 50 to 95% by weight, specifically 70 to 95% by weight, more specifically 80 to 95% by weight, or 85 to 95% by weight. Within this range, the flame retardancy, flowability, and reliability of the epoxy resin composition can be ensured.

[0039] curing catalyst The curing catalyst may be a tertiary amine compound, an organometallic compound, an organophosphorus compound, an imidazole compound, or a boron compound. Examples of tertiary amine compounds include benzyldimethylamine, triethanolamine, triethylenediamine, diethylaminoethanol, tri(dimethylaminomethyl)phenol, 2-2-(dimethylaminomethyl)phenol, 2,4,6-tris(diaminomethyl)phenol, and tri-2-ethylhexyl salt. Examples of organometallic compounds include chromium acetylacetonate, zinc acetylacetonate, and nickel acetylacetonate. Examples of organophosphorus compounds include triphenylphosphine, tris-4-methoxyphosphine, triphenylphosphine triphenylborane, and triphenylphosphine-1,4-benzoquinone adduct. Examples of imidazole compounds include 2-methylimidazole, 2-phenylimidazole, 2-aminoimidazole, 2-methyl-1-vinylimidazole, 2-ethyl-4-methylimidazole, and 2-heptadecylimidazole. Examples of boron compounds include triphenylphosphine tetraphenylborate, tetraphenylboron salts, trifluoroborane-n-hexylamine, trifluoroborane monoethylamine, tetrafluoroborane triethylamine, and tetrafluoroborane amine. Other compounds that can be used include 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.

[0040] As the curing catalyst, an adduct formed by a prior reaction with an epoxy resin or a curing agent can also be used.

[0041] The curing catalyst may be included in the epoxy resin composition in an amount of 0.01 to 10% by weight, for example, 0.01 to 5% by weight, which may ensure the fluidity of the composition without delaying the curing reaction time.

[0042] First Additive When the first additive is included in the composition, it reduces the moisture absorption rate, thereby suppressing the generation of voids in the multi-chip package, preventing the generation of cracks, and improving reliability.

[0043] The first additive includes zinc cyanurate. Generally, cyanuric acid is known as an enol form, triazine-2,4,6-triol, or a keto form, triazine-2,4,6-trione. However, since the enol form and the keto form are tautomers, the cyanuric acid can be used not only as the enol form, triazine-2,4,6-triol, but also as the keto form, triazine-2,4,6-trione.

[0044] The zinc cyanurate is a compound in which zinc is coordinately bonded to cyanuric acid, and may have a structure represented by Chemical Formula 5:

[0045] [ka] (Chemical formula 5)

[0046] According to one embodiment, the zinc cyanurate may be in the form of a salt.

[0047] The zinc cyanurate may preferably have a refractive index of 1.4 to 2.1 and be in a solid phase at room temperature. The zinc cyanurate may preferably have a moisture content of 1.5% or less and a density of 2.0 g / cm. 3 ~4.0g / cm 3 It may be preferable that:

[0048] The first additive, i.e., zinc cyanurate, may be included in the epoxy resin composition in an amount of 0.01 to 15 wt %. This range may facilitate reducing the moisture absorption rate of the composition and improving reliability. For example, the zinc cyanurate may be included in an amount of 0.1 to 5 wt %, or 0.1 to 3 wt %.

[0049] Second Additive The epoxy resin composition may further include a second additive, which may be a typical additive that may be included in an epoxy resin composition for sealing a multi-chip package or a semiconductor device. In specific examples, the second additive may include one or more of a coupling agent, a release agent, a colorant, a stress relief agent, a flame retardant, a crosslinking enhancer, and a leveling agent.

[0050] The coupling agent is intended to improve the interfacial strength by reacting between the epoxy resin and the inorganic filler, and may be, for example, 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 thereof is not particularly limited. Specific examples of the silane coupling agent include epoxy silane, amino silane, ureido silane, mercapto silane, and alkyl silane. For example, the silane coupling agent may be a mixture of mercapto silane, alkyl silane, and epoxy silane.

[0051] The coupling agents can be used alone or in combination. The coupling agent may be contained in the epoxy resin composition for encapsulating semiconductor devices in an amount of 0.01 to 5% by weight, preferably 0.05 to 3% by weight. Within this range, the strength of the cured product of the epoxy resin composition can be improved.

[0052] The release agent may be one or more 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, and may be contained in an amount of 0.1 to 1% by weight in the epoxy resin composition.

[0053] Carbon black can be used as the colorant, and the colorant may be contained in the epoxy resin composition in an amount of 0.1 to 1% by weight.

[0054] The stress relaxation agent may be one or more selected from the group consisting of modified silicone oil, silicone elastomer, silicone powder, and silicone resin, but is not limited thereto. Modified silicone oils are preferably silicone polymers with excellent heat resistance. One or more of silicone oils with epoxy functional groups, silicone oils with amine functional groups, and silicone oils with carboxyl functional groups can be mixed and used at 0.05 to 1.5 wt% of the total epoxy resin composition. However, if the silicone oil content exceeds 1.5 wt%, surface contamination may occur and resin bleeding may be prolonged. If the silicone oil content is less than 0.05 wt%, a sufficiently low elastic modulus may not be achieved. Furthermore, silicone powders with a median particle size of 15 μm or less are particularly preferred because they do not cause a decrease in moldability. Preferably, the silicone powder content is 0.05 to 5 wt% of the total resin composition.

[0055] The stress relaxation agent may be included in the epoxy resin composition in an amount of 0.1% to 6.5% by weight, for example, 0% to 1% by weight, for example, 0.1% to 1% by weight.

[0056] The flame retardant may be one or more of, but not limited to, antimony trioxide and phosphorus-based flame retardants, and may be included in the epoxy resin composition in an amount of 0 to 2 wt %, for example, 0 to 1.5 wt %, or 0.1 to 1 wt %.

[0057] The second additive may be included in the epoxy resin composition in an amount of 0.1% to 5% by weight, for example, 0.1% to 3% by weight.

[0058] The method for producing the epoxy resin composition is not particularly limited, but the composition may be produced by uniformly mixing the components contained in the composition using a Henschel mixer or a Loedige mixer, melt-kneading the components at 90°C to 120°C using a roll mill or a kneader, and then cooling and pulverizing the components.

[0059] Multi-chip packages are sealed using the epoxy resin composition for sealing multi-chip packages of the present invention. Methods for sealing multi-chip packages using the epoxy resin composition include, but are not limited to, transfer molding, injection molding, casting molding, and compression molding. In one embodiment, the multi-chip package of the present invention may be sealed using a low-pressure transfer molding method, and in another embodiment, it may be sealed using compression molding. [Example]

[0060] The structure and operation of the present invention will be described in more detail below through preferred examples of the present invention, which are presented as preferred examples of the present invention and should not be construed as limiting the present invention in any way.

[0061] The specific specifications of the components used in the following examples and comparative examples are as follows:

[0062] (A) Epoxy resin (A1) Biphenyl-type epoxy resin (YX-4000H, manufactured by JER, epoxy equivalent = 190 g / eq) (A2) Phenol aralkyl epoxy resin (NC-3000, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent = 270 g / eq)

[0063] (B) Hardener (B1) Zylok-type phenolic resin (MEH-7800-4S, manufactured by Meiwa Chemical Industry Co., Ltd., hydroxyl group equivalent = 175 g / eq) (B2) Phenol aralkyl phenolic resin (MEH-7851-SS, manufactured by Meiwa Chemical Industry Co., Ltd., hydroxyl group equivalent = 200 g / eq) (B3) Phenol novolac type phenolic resin (H-4, manufactured by Meiwa Chemical Industry Co., Ltd., hydroxyl group equivalent = 100 g / eq)

[0064] (C) Curing catalyst: triphenylphosphine (manufactured by Hokko Chemical Industry Co., Ltd.)

[0065] (D) Inorganic filler: average particle size (D 50 ) 20 μm spherical fused silica: average particle size (D 50 ) 0.5 μm spherical fused silica in a 9:1 weight ratio mixture

[0066] (E) Zinc cyanurate (Starfine, Nissan Chemical Co., Ltd., moisture content 0.9 wt.%, density 3.0 g / cm 3 , refractive index 1.7)

[0067] (F) Coupling agent (F1) γ-glycidoxypropyltrimethoxysilane (epoxysilane) (F2) Mercaptopropyltrimethoxysilane (mercaptosilane) (F3) Methyltrimethoxysilane (alkylsilane)

[0068] (G) Antimony trioxide

[0069] (H) Silicone powder

[0070] (I) Carbon black (MA-600B, manufactured by Mitsubishi Chemical Corporation)

[0071] (J) Carnauba wax

[0072] Examples 1 to 4 and Comparative Examples 1 to 3 The epoxy resin compositions for semiconductor device encapsulation were prepared by uniformly mixing the components (unit: parts by weight) in Table 1 below using a Henschel mixer (Kunsan Machinery, KSM-22) at 25-30°C for 30 minutes, then melt-kneading them in a continuous kneader at a maximum of 110°C for 30 minutes, cooling them to 10-15°C, and pulverizing them. In Table 1 below, "-" means that the corresponding component is not included.

[0073] The prepared epoxy resin compositions for sealing semiconductor elements were evaluated for the following physical properties, and the results are shown in Table 2 below.

[0074] (1) Fluidity (unit: inch, spiral flow): Using a low-pressure transfer molding machine, the fluidity measurement mold was measured in accordance with EMMI-1-66 at a mold temperature of 175°C and 70 kgf / cm 2 The epoxy resin composition for sealing semiconductor devices was injected under conditions of an injection pressure of 9 MPa and a curing time of 90 seconds, and the flow length was measured. The higher the measured value, the better the flowability.

[0075] (2) Flexural strength (unit: kgf / mm 2 ) and flexural modulus (unit: kgf / mm 2 ) The toughness was measured by preparing a standard test piece (125mm x 12.6mm x 6.4mm) from the epoxy resin composition for semiconductor element encapsulation in accordance with ASTM D-790, curing the test piece at 175°C for 4 hours, and then measuring the toughness at 260°C using a UTM (Universal Testing Machine).

[0076] (3) Moisture absorption rate (unit: weight %): The resin compositions prepared in the examples and comparative examples were subjected to a mold temperature of 170 to 180°C and a clamp pressure of 70 kgf / cm. 2The specimens were molded under conditions of a transfer pressure of 1000 psi, a transfer speed of 0.5 to 1 cm / s, and a curing time of 120 seconds to obtain disc-shaped cured specimens with a diameter of 50 mm and a thickness of 1.0 mm. The specimens were placed in an oven at 170 to 180°C and post-molding cured for 4 hours (PMC), and then left at 85°C and 85% RH for 168 hours. The weight change due to moisture absorption was measured, and the moisture absorption rate was calculated using the following equation 1.

[0077]

number

[0078] (4) Reliability (unit: piece): The manufactured composition was subjected to preconditioning treatment, and after 1000 cycles of thermal shock testing, the presence or absence of cracks was evaluated using SAT (scanning acoustic tomograph), a non-destructive test.

[0079] <Precondition> The multi-chip packages made with the epoxy resin compositions were dried at 125°C for 24 hours, subjected to five cycles of thermal shock testing, and then left at 85°C and 85% relative humidity for 96 hours. They were then subjected to IR reflow at 260°C for 10 seconds, a cycle repeated three times. The multi-chip packages were then evaluated for cracking. If cracks were found, the following thermal shock testing was not performed.

[0080] <Thermal shock> The multi-chip packages that had passed the preconditioning were subjected to a total of 1,000 cycles, with one cycle consisting of 10 minutes at -65°C, 5 minutes at 25°C, and 10 minutes at 150°C. After that, the presence or absence of internal and external cracks was evaluated using SAT, a non-destructive testing method.

[0081] <Reliability> For reliability testing, the product was molded at 175°C for 70 seconds using an MPS (Multi Plunger System) molding machine, and then post-cured at 175°C for 2 hours to create a multi-chip package in which four semiconductor chips were stacked one above the other with an organic adhesive film. Reliability was evaluated by the degree of cracking of the package during a thermal shock test.

[0082] (5) Formability: The number of voids generated in the package used in the reliability evaluation was checked with the naked eye.

[0083] [Table 1]

[0084] [Table 2]

[0085] As shown in Table 2, the epoxy resin compositions for sealing multi-chip packages according to the examples can prevent cracks in the multi-chip package by suppressing the generation of voids during molding of the multi-chip package, thereby improving moldability and reliability.

[0086] Simple variations and modifications of the present invention can be easily implemented by those skilled in the art, and all such variations and modifications can be considered to be included within the scope of the present invention.

Claims

1. Epoxy resin, A hardener; an inorganic filler; A curing catalyst; a first additive; the first additive comprises zinc cyanurate; Epoxy resin composition for sealing multi-chip packages.

2. The zinc cyanurate is contained in the epoxy resin composition in an amount of 0.01% by weight to 15% by weight.

2. The epoxy resin composition for sealing a multi-chip package according to claim 1.

3. The zinc cyanurate is represented by the following chemical formula 5: The epoxy resin composition for sealing a multi-chip package according to claim 1, 【Chemistry 1】 (Chemical formula 5)

4. The epoxy resin includes at least one of a biphenyl type epoxy resin, a phenol aralkyl type epoxy resin, and a halogenated epoxy resin.

2. The epoxy resin composition for sealing a multi-chip package according to claim 1.

5. The curing agent includes at least one of a Zylok type phenolic resin, a phenol aralkyl type phenolic resin, and a phenol novolac type phenolic resin.

2. The epoxy resin composition for sealing a multi-chip package according to claim 1.

6. The composition comprises: 2% to 17% by weight of the epoxy resin, 0.1% to 13% by weight of the curing agent; 50% to 95% by weight of the inorganic filler, 0.01% to 10% by weight of the curing catalyst, and The first additive is present in an amount of 0.01% by weight to 15% by weight.

2. The epoxy resin composition for sealing a multi-chip package according to claim 1.

7. A semiconductor element sealed with the epoxy resin composition for sealing semiconductor elements according to any one of claims 1 to 6.

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