JP4697476B2 - Liquid epoxy resin composition and flip chip type semiconductor device - Google Patents

Description

  INDUSTRIAL APPLICABILITY The present invention has a low viscosity for sealing semiconductors, particularly flip-chip type semiconductor devices, and is very suitable for workability. Is a liquid epoxy resin composition that gives a cured product with very good moisture resistance and can be an excellent sealing material against a high-temperature thermal shock particularly at a reflow temperature of 260 ° C. or higher, and a cured product of this composition The present invention relates to a flip-chip type semiconductor device that is sealed.

  Along with the downsizing, weight reduction, and higher functionality of electrical equipment, semiconductor mounting methods have become mainstream from pin insertion type to surface mounting. In addition, along with the high integration of semiconductor elements, there are cases in which one side of the die size exceeds 10 mm, and the die size is increasing. In a semiconductor device using such a large die, the stress applied to the die and the sealing material increases during solder reflow, and peeling occurs at the interface between the sealing material and the die and the substrate, or the package cracks when mounted on the substrate. These issues have been highlighted.

  Furthermore, since lead-containing solder cannot be used in the near future, a number of lead substitute solders have been developed. Since this type of solder has a melting temperature higher than that of lead-containing solder, the reflow temperature is also examined at 260 to 270 ° C., and the conventional liquid epoxy resin composition sealing material is even more defective. Is expected. Thus, when the reflow temperature becomes high, the flip chip type package, which has not had any problems in the prior art, also generates cracks during reflow, separation from the chip interface and the substrate interface, and subsequent cooling cycles. When several hundred times or more have passed, a serious problem that a crack occurs in a resin, a substrate, a chip, or a bump portion has come to occur.

  Further, with the progress of high integration, there has been a problem in the flip chip type semiconductor device that the pitch between the bumps becomes narrow and the injectability becomes worse.

  As prior art documents related to the present invention, there are the following.

JP-A-10-158366 JP-A-10-231351 JP 2000-327884 A Japanese Patent Laid-Open No. 2001-055486 JP 2001-055487 A JP 2001-055488 A

  The present invention has been made in view of the above circumstances, and provides a cured product having excellent adhesion to the surface of a silicon chip, particularly a photosensitive polyimide resin or a nitride film, and excellent toughness, and the reflow temperature is the conventional temperature. Even if the temperature rises from around 240 ° C to 260-270 ° C, no defects occur, and it does not deteriorate even under high temperature and high humidity conditions such as PCT (121 ° C / 2.1 atm), and the temperature cycle is -65 ° C / 150 ° C. The present invention provides a liquid epoxy resin composition that can be used as a sealing material for a semiconductor device in which peeling and cracking do not occur even if it exceeds several hundred cycles, and a flip chip type semiconductor device sealed with a cured product of this composition. Objective.

  As a result of intensive studies to achieve the above object, the present inventor has obtained a liquid epoxy resin composition containing (A) a liquid epoxy resin, (B) an aromatic amine-based curing agent, and (C) an inorganic filler. (A) As a liquid epoxy resin, an epoxy resin represented by the following structural formula (4) or (5), particularly an epoxy resin represented by the following structural formula (5) is 25% by weight in the total epoxy resin By using an aromatic amine compound containing 5% by weight or more of the aromatic amine compound represented by the following general formula (1) as the aromatic amine-based curing agent, the viscosity is low and the workability is low. Excellent adhesion to the surface of the silicon chip, especially photosensitive polyimide resin and nitride film, especially nitride film, and does not deteriorate even under high temperature and high humidity conditions such as PCT (120 ° C / 2.1 atm), Against thermal shock Excellent was found that particularly effective as a sealing material for a semiconductor device of a large die size.

（式中、Ｒ⁸は水素原子、又は炭素数１〜２０の一価炭化水素基である。また、ｘは１〜４の整数である。）

(In the formula, R ⁸ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. X is an integer of 1 to 4.)

（式中、Ｒ¹〜Ｒ³は独立に炭素数１〜６の一価炭化水素基、ＣＨ₃Ｓ−及びＣ₂Ｈ₅Ｓ−から選ばれる基である。）

(In the formula, R ^{1 to} R ³ are groups independently selected from a monovalent hydrocarbon group having 1 to 6 carbon atoms, CH ₃ S— and C ₂ H ₅ S—.)

  That is, the aromatic amine-based curing agent represented by the general formula (1) has a specific substituent compared to the conventional aromatic amine-based curing agent, so that it is cured relatively quickly. It has a long pot life and is excellent in mechanical properties, electrical properties, heat resistance properties and chemical resistance properties of the cured product. By using this curing agent, the surface of the silicon chip, particularly with the photosensitive polyimide resin or nitride film, It has been found that the adhesiveness is excellent, the thermal shock resistance is remarkably improved, and excellent characteristics can be obtained even under high temperature and high humidity.

  Furthermore, since the aromatic amine curing agent of the present invention has a lower viscosity than the conventional aromatic amine curing agent, the viscosity of the composition can be lowered. In particular, in the narrow gap flip chip type semiconductor device, the injection is possible. It has been found that workability is improved because no voids are generated at the time and during curing, and that it can be effectively used as a sealing material for a semiconductor device having a large die size, and the present invention has been made.

（式中、Ｒ ⁸ は水素原子、又は炭素数１〜２０の一価炭化水素基である。また、ｘは１〜４の整数である。）
（Ｂ）下記一般式（１）で表される芳香族アミン化合物を５重量％以上含有する芳香族アミン系硬化剤を（Ａ）液状エポキシ樹脂と（Ｂ）芳香族アミン系硬化剤との配合モル比［（Ａ）／（Ｂ）］が、０．７以上１．２以下である量

（式中、Ｒ ¹ 〜Ｒ ³ は独立に炭素数１〜６の一価炭化水素基、ＣＨ ₃ Ｓ−及びＣ ₂ Ｈ ₅ Ｓ−から選ばれる基である。）
（Ｃ）無機質充填剤を（Ａ）液状エポキシ樹脂と（Ｂ）芳香族アミン系硬化剤の合計量１００重量部に対して５０〜５００重量部
を含有し、更に沸点が１３０℃以上２５０℃以下の有機溶剤を（Ａ）液状エポキシ樹脂と（Ｂ）芳香族アミン系硬化剤の合計量１００重量部に対して０．５〜１０重量部含有することを特徴とする液状エポキシ樹脂組成物、
及び
（Ａ）１分子内に３官能基以下のエポキシ基を含有する常温で液状の液状エポキシ樹脂であって、下記構造式（５）で示されるエポキシ樹脂を全エポキシ樹脂中２５重量％以上含む液状エポキシ樹脂

（式中、Ｒ ⁸ は水素原子、又は炭素数１〜２０の一価炭化水素基である。また、ｘは１〜４の整数である。）
（Ｂ）下記一般式（１）で表される芳香族アミン化合物を５重量％以上含有する芳香族アミン系硬化剤を（Ａ）液状エポキシ樹脂と（Ｂ）芳香族アミン系硬化剤との配合モル比［（Ａ）／（Ｂ）］が、０．７以上１．２以下である量

（式中、Ｒ ¹ 〜Ｒ ³ は独立に炭素数１〜６の一価炭化水素基、ＣＨ ₃ Ｓ−及びＣ ₂ Ｈ ₅ Ｓ−から選ばれる基である。）
（Ｃ）無機質充填剤を（Ａ）液状エポキシ樹脂と（Ｂ）芳香族アミン系硬化剤の合計量１００重量部に対して５０〜５００重量部
を含有することを特徴とする液状エポキシ樹脂組成物
を提供する。 Therefore, the present invention
(A) 1 contains 3 or less epoxy functional groups in the molecule a liquid epoxy resin that is liquid at room temperature, liquid epoxy resin containing an epoxy resin represented by the following Symbol structural formula (4) or (5)

(In the formula, R ⁸ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. X is an integer of 1 to 4.)
(B) under following general formula (1) an aromatic amine curing agent containing an aromatic amine compound 5 wt% or more represented by (A) of a liquid epoxy resin and (B) an aromatic amine curing agent The amount that the blending molar ratio [(A) / (B)] is 0.7 or more and 1.2 or less

(In the formula, R ^{1 to} R ³ are groups independently selected from a monovalent hydrocarbon group having 1 to 6 carbon atoms, CH ₃ S— and C ₂ H ₅ S—.)
(C) The inorganic filler contains 50 to 500 parts by weight with respect to 100 parts by weight of the total amount of (A) liquid epoxy resin and (B) aromatic amine curing agent , and further has a boiling point of 130 ° C to 250 ° C. A liquid epoxy resin composition comprising 0.5 to 10 parts by weight of the organic solvent (A) with respect to 100 parts by weight of the total amount of (A) liquid epoxy resin and (B) aromatic amine curing agent ,
as well as
(A) A liquid epoxy resin that is liquid at room temperature and contains an epoxy group having three or less functional groups in one molecule, and includes 25% by weight or more of the epoxy resin represented by the following structural formula (5) in the total epoxy resin Epoxy resin

(In the formula, R ⁸ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. X is an integer of 1 to 4.)
(B) An aromatic amine curing agent containing 5% by weight or more of an aromatic amine compound represented by the following general formula (1) is blended with (A) a liquid epoxy resin and (B) an aromatic amine curing agent. Amount in which the molar ratio [(A) / (B)] is 0.7 or more and 1.2 or less

(In the formula, R ^{1 to} R ³ are groups independently selected from a monovalent hydrocarbon group having 1 to 6 carbon atoms, CH ₃ S— and C ₂ H ₅ S—.)
(C) The inorganic filler is 50 to 500 parts by weight with respect to 100 parts by weight of the total amount of (A) liquid epoxy resin and (B) aromatic amine curing agent.
A liquid epoxy resin composition comprising:

  The present invention provides a flip chip type semiconductor device in which, in addition to the liquid epoxy resin composition, a cured product of the liquid epoxy resin composition is sealed as an underfill material.

  The liquid epoxy resin composition of the present invention has a low viscosity, excellent workability, gives a cured product with excellent adhesion to the surface of a silicon chip, particularly a photosensitive polyimide resin and a nitride film, and reflow after moisture absorption Even if the temperature of the conventional material rises from about 240 ° C. to about 260 to 270 ° C., no defects occur, and it does not deteriorate even under high temperature and high humidity conditions such as PCT (120 ° C./2.1 atm). It is possible to provide a semiconductor device in which peeling and cracking do not occur even when the temperature cycle of 150 ° C. exceeds several hundred cycles.

Hereinafter, the present invention will be described in more detail.
In the liquid epoxy resin composition of the present invention, any liquid epoxy resin (A) can be used as long as it is a liquid epoxy resin at room temperature containing an epoxy group having three or less functional groups in one molecule, Those having a viscosity at 25 ° C. of 2,000 poises or less, particularly 500 poises or less are preferable. Specifically, bisphenol type epoxy resins such as bisphenol A type epoxy resins and bisphenol F type epoxy resins, naphthalene type epoxy resins, phenylglycidyl An ether etc. are mentioned, In this, a liquid epoxy resin is used at room temperature.

Moreover, the epoxy resin of this invention may contain the epoxy resin shown by following Structural formula (4), (5) in the range which does not affect intrusion property.

Here, R ⁸ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 3 carbon atoms, and examples of the monovalent hydrocarbon group include a methyl group and an ethyl group. And alkyl groups such as propyl group, alkenyl groups such as vinyl group and allyl group. X is an integer of 1 to 4, particularly 1 or 2.

In addition, when mix | blending the epoxy resin shown by the said Formula (5), the compounding quantity is 25 weight% or more in all the epoxy resins, More preferably, it is 50 weight% or more, More preferably, it is 75 weight% or more. Recommended. If it is less than 25% by weight, the viscosity of the composition may increase or the heat resistance of the cured product may decrease. The upper limit may be 100% by weight.
Examples of the epoxy resin represented by the general formula (5) include RE600NM manufactured by Nippon Kayaku Co., Ltd.

  The total chlorine content in the liquid epoxy resin is preferably 1,500 ppm or less, more preferably 1,000 ppm or less. Moreover, it is preferable that the extraction water chlorine in 20 hours in the 50% epoxy resin density | concentration at 100 degreeC is 10 ppm or less. If the total chlorine content exceeds 1,500 ppm or the extracted water chlorine exceeds 10 ppm, the reliability of the semiconductor element, particularly the moisture resistance, may be adversely affected.

  Next, the aromatic amine curing agent (B) used in the present invention contains an aromatic amine compound represented by the following general formula (1) in a total aromatic amine curing agent in an amount of 5% by weight or more. It is.

（式中、Ｒ¹〜Ｒ³は独立に炭素数１〜６の一価炭化水素基、ＣＨ₃Ｓ−及びＣ₂Ｈ₅Ｓ−から選ばれる基である。）

(In the formula, R ^{1 to} R ³ are groups independently selected from a monovalent hydrocarbon group having 1 to 6 carbon atoms, CH ₃ S— and C ₂ H ₅ S—.)

Here, the monovalent hydrocarbon group of R ^{1 to} R ³ is preferably a group having 1 to 6 carbon atoms, particularly 1 to 3 carbon atoms, and preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, Alkyl groups such as tert-butyl group and hexyl group, vinyl groups, allyl groups, propenyl groups, butenyl groups, alkenyl groups such as hexenyl groups, phenyl groups, etc., and some or all of hydrogen atoms of these hydrocarbon groups And halogen-substituted monovalent hydrocarbon groups such as a fluoromethyl group, a bromoethyl group, and a trifluoropropyl group substituted with a halogen atom such as chlorine, fluorine, and bromine.

  Specific examples of the aromatic amine compound represented by the general formula (1) include diethyltoluenediamine, dimethylthiotoluenediamine, and dimethyltoluenediamine.

  The amount of the aromatic amine compound represented by the general formula (1) is 5% by weight or more, preferably 10 to 100% by weight, more preferably 20 to 100% by weight, based on the whole aromatic amine-based curing agent. . When the aromatic amine compound represented by the general formula (1) is less than 5% by weight of the entire curing agent, the viscosity increases, the adhesive strength decreases, or cracks occur.

  Examples of the curing agent other than the aromatic amine compound include aromatic diaminodiphenylmethane compounds such as 3,3′-diethyl-4,4′-diaminophenylmethane, 3,3 ′, 5,5′-tetramethyl. -4,4'-diaminophenylmethane, 3,3 ', 5,5'-tetraethyl-4,4'-diaminophenylmethane, 2,4-diaminotoluene, 1,4-diaminobenzene, 1,3-diamino An aromatic amine such as benzene is preferred.

  Among the aromatic amine-based curing agents, those which are liquid at room temperature can be blended as they are, but if they are blended as they are, the viscosity of the resin increases and workability becomes significantly worse. It is preferable to melt and mix with an epoxy resin, and it is desirable to melt and mix in a temperature range of 70 to 150 ° C. for 1 to 2 hours at a specified blending ratio described later. If the mixing temperature is less than 70 ° C., the aromatic amine curing agent may not be sufficiently compatible, and if the mixing temperature exceeds 150 ° C., it may react with the epoxy resin and increase the viscosity. Also, if the mixing time is less than 1 hour, the aromatic amine curing agent is not sufficiently compatible and may increase the viscosity, and if it exceeds 2 hours, it may react with the epoxy resin and increase the viscosity. .

  The total blending amount of the aromatic amine curing agent used in the present invention is the molar ratio of the liquid epoxy resin and the aromatic amine curing agent [(A) liquid epoxy resin / (B) aromatic amine curing. It is recommended that the agent is in the range of 0.7 to 1.2, preferably 0.7 to 1.1, and more preferably 0.85 to 1.05. If the blending molar ratio is less than 0.7, unreacted amino groups remain, and the glass transition temperature may be lowered and the adhesion may be lowered. On the other hand, if it exceeds 1.2, the cured product becomes hard and brittle, and cracks may occur during reflow or temperature cycling.

  On the other hand, various inorganic fillers conventionally known can be added to the inorganic filler (C) used in the present invention for the purpose of reducing the expansion coefficient. Specific examples of the inorganic filler include fused silica, crystalline silica, alumina, boron nitride, ticker aluminum, ticker silicon, magnesia, magnesium silicate, aluminum and the like. Among them, spherical fused silica is desirable for reducing the viscosity. These inorganic fillers may be surface-treated with a silane coupling agent or the like, but can be used without surface treatment.

  Here, the semiconductor device targeted by the present invention is preferably a flip chip type semiconductor device having a gap size in the range of about 10 to 200 μm. In this case, both improvement in penetration of the underfill material and reduction in linear expansion are achieved. Therefore, it is preferable to use an inorganic filler having an average particle size of about 1/10 or less and a maximum particle size of 1/2 or less with respect to the flip chip gap width (gap between the substrate and the semiconductor chip). More preferably, the average particle diameter is 0.1 to 5 μm and the particle diameter is ½ or more with respect to the gap size of the flip chip type semiconductor device is 0.1% by weight or less of the whole inorganic filler. It is desirable to use some inorganic filler. When the average particle size is smaller than 0.1 μm, the viscosity may increase. When the average particle size exceeds 5 μm, the gap may be caught between the gaps and may be unfilled.

  Here, as a method for measuring a particle having a particle size of 1/2 or more with respect to the gap size, for example, an inorganic filler and pure water are mixed at a ratio of 1: 9 (weight), and subjected to ultrasonic treatment to agglomerate. It is possible to use a particle size inspection method in which an object is sufficiently broken, sieved with a filter having an opening of ½ of the gap size, and the remaining amount on the sieve is weighed.

  As a compounding quantity of an inorganic filler (C), it is preferable to set it as 50-500 weight part with respect to a total of 100 weight part of an epoxy resin and a hardening | curing agent, More preferably, it is the range of 100-400 weight part. If it is less than 50 parts by weight, the expansion coefficient is large and there is a risk of inducing the occurrence of cracks in the cold test. Moreover, when it exceeds 500 weight part, there exists a possibility that a viscosity may become high and the thin film penetration property may be brought about.

  Furthermore, in the liquid epoxy resin composition of the present invention, it is preferable to use an organic solvent having a boiling point of 130 ° C. or higher and 250 ° C. or lower for the purpose of improving workability and reducing the viscosity. The boiling point of the organic solvent is more preferably 140 ° C. or higher and 230 ° C. or lower, and further preferably 150 ° C. or higher and 230 ° C. or lower. If the boiling point is less than 130 ° C., the solvent volatilizes during dispensing or curing, and voids may be generated. On the other hand, if the temperature exceeds 250 ° C., the solvent cannot be completely volatilized at the time of curing, which may cause a decrease in strength and a decrease in adhesion.

  Examples of such organic solvents include 2-ethoxyethanol, 1,2-propanediol, 1,2-ethanediol, diethylene glycol, xylene, cyclohexanone, cyclohexanol, formamide, acetamide, diethylene glycol monoethyl ether acetate, and the like. It is done.

A more preferable organic solvent is an ester organic solvent. In an alcohol solvent other than an ester organic solvent or an organic solvent having a hydroxyl group, the hydroxyl group and the amine easily react and the storage stability may be significantly deteriorated. From such a standpoint, in view of safety, ester organic solvents are preferable. Examples of such ester organic solvents include ester organic solvents represented by the following general formula (2).
^{R 4 COO- [R 5 -O]} n -R 6 (2)
(Wherein R ⁴ and R ⁶ are monovalent hydrocarbon groups having 1 to 6 carbon atoms, R ⁵ is an alkylene group having 1 to 6 carbon atoms, and n is an integer of 0 to 3)

Here, examples of the monovalent hydrocarbon group having 1 to ⁶ carbon atoms of R ⁴ and R ⁶ include the same groups as those of R ^{1 to} R ³ described above, and an alkylene group having 1 to 6 carbon atoms of R ^5. Examples thereof include an ethylene group, a propylene group, a methylethylene group, a butylene group, a pentene group, and a hexene group.

  Specific examples of the ester organic solvent represented by the above formula (2) include 2-ethoxyethyl acetate, 2-butoxyethyl acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol butyl ether acetate. Etc.

  The compounding amount of the organic solvent is 0.5 to 10 parts by weight, desirably 1 to 10 parts by weight with respect to 100 parts by weight of the total amount of the epoxy resin and the curing agent in the composition. If the amount is less than 0.5 part by weight, a sufficient viscosity reducing effect cannot be obtained. If the amount exceeds 10 parts by weight, the crosslinking density decreases, and sufficient strength cannot be obtained.

  The liquid epoxy resin composition of the present invention may be blended with silicone rubber, silicone oil, liquid polybutadiene rubber, thermoplastic resin made of methyl methacrylate-butadiene-styrene, or the like for the purpose of reducing stress. Preferably, the alkenyl group of the alkenyl group-containing epoxy resin or phenol resin, and the number of silicon atoms in one molecule represented by the following average composition formula (3) is 20 to 400, and a hydrogen atom bonded directly to the silicon atom It is preferable to blend a silicone-modified resin made of a copolymer obtained by an addition reaction with an SiH group of an organopolysiloxane having 1 to 5 (SiH groups).

H _a R ⁷ _b SiO _{(4-ab) / 2} (3)
(In the formula, R ⁷ is a substituted or unsubstituted monovalent hydrocarbon group, a is 0.01 to 0.1, b is 1.8 to 2.2, and 1.81 ≦ a + b ≦ 2.3 is satisfied. (It is a positive number.)

The substituted or unsubstituted monovalent hydrocarbon group for R ⁷ is preferably a group having 1 to 10 carbon atoms, particularly 1 to 8 carbon atoms, and is preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, or an isobutyl group. Alkyl groups such as tert-butyl group, hexyl group, octyl group and decyl group, alkenyl groups such as vinyl group, allyl group, propenyl group, butenyl group and hexenyl group, and aryl groups such as phenyl group, xylyl group and tolyl group , Aralkyl groups such as benzyl group, phenylethyl group, phenylpropyl group, etc., and fluoromethyl group, bromoethyl group, in which part or all of hydrogen atoms of these hydrocarbon groups are substituted with halogen atoms such as chlorine, fluorine, bromine, And halogen-substituted monovalent hydrocarbon groups such as a trifluoropropyl group.
Among the above copolymers, those having the following structures are desirable.

In the above formula, R ⁷ is the same as above, and R ⁹ is a hydrogen atom or an alkyl such as a methyl group having 1 to 4 carbon atoms, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, or a tert-butyl group. R ¹⁰ is —CH ₂ CH ₂ CH ₂ —, —OCH ₂ —CH (OH) —CH ₂ —O—CH ₂ CH ₂ CH ₂ — or —O—CH ₂ CH ₂ CH ₂ —. . m is an integer of 4 to 199, preferably 19 to 99, p is an integer of 1 to 10, and q is an integer of 1 to 10.

  The stress can be further reduced by blending the copolymer so that the diorganopolysiloxane unit is contained in an amount of 0 to 20 parts by weight, particularly 2 to 15 parts by weight, based on 100 parts by weight of the epoxy resin.

  In the liquid epoxy resin composition of the present invention, if necessary, a carbon functional silane for improving adhesion, a pigment such as carbon black, a dye, an antioxidant, and other additives within a range not impairing the object of the present invention. Can be blended. However, in the present invention, it is preferable not to add an alkoxy-based silane coupling agent as a carbon-functional silane for improving adhesion other than the use as a surface treatment agent.

  The liquid epoxy resin composition of the present invention includes, for example, a liquid epoxy resin, an aromatic amine curing agent, a molten mixture of a liquid epoxy resin and an aromatic amine curing agent, an inorganic filler, and an organic solvent as necessary. And other additives can be obtained by stirring, dissolving, mixing, and dispersing at the same time or separately, optionally with heat treatment. The apparatus for mixing, stirring, dispersing and the like is not particularly limited, and a lykai machine, a three roll, a ball mill, a planetary mixer, a bead mill and the like equipped with a stirring and heating device can be used. Moreover, you may use combining these apparatuses suitably.

  In the present invention, the viscosity of the liquid epoxy resin composition when used as a sealing material is preferably 10,000 poise or less, particularly preferably 10 to 1,000 poise at 25 ° C. Further, the molding method and molding conditions of this composition can be conventional methods, but preferably at 100 to 120 ° C. for 0.5 hour or longer, particularly 0.5 to 1 hour, and then at 165 ° C. Heat oven cure is performed under conditions of 1 hour or more, particularly 1 to 4 hours. When heating at 100 to 120 ° C. is less than 0.5 hour, voids may be generated after curing, and when heating at 165 ° C. is less than 1 hour, sufficient cured product characteristics may not be obtained.

  Here, as a flip chip type semiconductor device used in the present invention, for example, as shown in FIG. 1, for example, a semiconductor chip 3 is usually mounted on a wiring pattern surface of an organic substrate 1 via a plurality of bumps 2. The gap between the organic substrate 1 and the semiconductor chip 3 (the gap between the bumps 2) is filled with the underfill material 4 and the side portion thereof is sealed with the fillet material 5. The sealing material of the present invention is particularly effective when used as an underfill material.

  When using the liquid epoxy resin composition of this invention as an underfill material, it is preferable that the expansion coefficient below the glass transition temperature of the hardened | cured material is 20-40 ppm / degreeC. As a means for obtaining such an expansion coefficient, for example, a method of blending 100 to 400 parts by weight of the inorganic filler with respect to 100 parts by weight of the total of the epoxy resin and the curing agent can be employed.

  In this case, the sealing material for the fillet material may be a known material, and in particular, a liquid epoxy resin composition similar to the above-described underfill material can be used. In this case, the glass transition temperature of the cured product is used. The following expansion coefficient is preferably 10 to 20 ppm / ° C.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not restrict | limited to the following Example.

[Examples 1 to 5, Reference Examples 1 to 5 , Comparative Examples 1 and 2]
Twelve types of resin compositions were obtained by uniformly kneading the components shown in Table 1 with three rolls. The test shown below was done using these resin compositions. The results are shown in Table 1.

[viscosity]
The viscosity at 25 ° C. was measured at a rotation speed of 4 rpm using a BH type rotational viscometer. Moreover, it measured also in the viscosity (25 degreeC) after leaving to stand at 40 degreeC for 24 hours.

[Penetration test]
A 10 mm x 10 mm silicon chip coated with PI (polyimide) film was placed on a 30 mm x 30 mm FR-4 substrate using a spacer of about 50 μm, and the resin composition was heated at 100 ° C. in the generated gap. The resin composition that had been installed and melted was allowed to enter, and the time when the resin composition filled the gap was measured.

[Void test]
PI chip coated 10mm x 10mm silicon chip using 30mm x 30mm FR-4 substrate, flip chip type package with gap of about 50μm, intruding and curing resin composition in the generated gap, presence or absence of void Was confirmed by C-SAM (manufactured by SONIX).

[Tg (glass transition temperature), CTE1 (expansion coefficient), CTE2 (expansion coefficient)]
Using a cured product test piece of 5 mm × 5 mm × 15 mm, Tg was measured when the temperature was raised at a rate of 5 ° C. per minute by TMA (thermomechanical analyzer). Moreover, the expansion coefficient in the following temperature range was measured.
The temperature range of CTE1 is 50 to 80 ° C, and the temperature range of CTE2 is 200 to 230 ° C.

[Adhesion test]
A test piece in the shape of a truncated cone having a diameter of 2 mm on the upper surface, a diameter of 5 mm on the lower surface, and a height of 3 mm was placed on a silicon chip coated with PI film and cured at 165 ° C. for 3 hours. After curing, the shear strength of the obtained specimen was measured and used as the initial value. Further, the cured test piece was absorbed with PCT (121 ° C./2.1 atm) for 336 hours, and then the adhesive strength was measured. In any case, the number of test pieces was five, and the average value was expressed as adhesive strength.

[PCT peel test]
Using a flip chip type package with a gap of about 50 μm, using a silicon chip of 10 mm × 10 mm coated with a PI film and a FR-4 substrate of 30 mm × 30 mm, the resin composition is penetrated into the generated gap, cured, and 30 ° C. / 65% RH / 192 hours later, stripping after 5 treatments with IR reflow set to a maximum temperature of 265 ° C., and placing in a PCT (121 ° C./2.1 atm) environment, stripping after 336 hours is C- It confirmed with SAM (made by SONIX).

[Thermal shock test]
Using a flip chip type package with a gap of about 50 μm, using a silicon chip of 10 mm × 10 mm coated with a PI film and a FR-4 substrate of 30 mm × 30 mm, the resin composition is penetrated into the generated gap, cured, and 30 ° C. / 65% RH / 192 hours later, IR reflow set to the maximum temperature of 265 ° C 5 times, then -65 ° C / 30 minutes, 150 ° C / 30 minutes as one cycle, 250, 500, 750, 1000 cycles later Peeling and cracking were confirmed.

Curing agent A: diethyltoluenediamine (molecular weight: 178)
Curing agent B: dimethylthiotoluenediamine (molecular weight: 214.4)
Curing agent C: dimethyltoluenediamine (molecular weight: 150)
C-300S: Tetraethyldiaminophenylmethane (Nippon Kayaku Co., Ltd.)
RE303S-L: Bisphenol F type epoxy resin (Nippon Kayaku Co., Ltd.)

Epicoat 630H: Trifunctional epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd.)

RE600NM: 5-methylresorcinol diglycidyl ether (manufactured by Nippon Kayaku Co., Ltd.)

Silica A: A particle size of 25 μm or more measured by the following particle size inspection method is 0.01% by weight.
Spherical silica silica B produced by a sol-gel method having an average particle size of 3.2 μm: a particle size of 25 μm or more measured by the following particle size inspection method is 0.08 wt%
, Spherical silica produced by the sol-gel method with an average particle size of 3.6 μm
Particle size inspection method Silica and pure water are mixed at a ratio of 1: 9 (weight), and ultrasonic treatment is performed to sufficiently break up the aggregates, and sieved with a filter 1 (aperture 25 μm). The remaining amount was measured by weighing. The measurement was carried out 5 times, and the average value was expressed as a percentage by weight.

Solvent A: 2-butoxyethyl acetate Boiling point 192 ° C
Solvent B: PGMEA Boiling point 146 ° C
KBM403: Silane coupling agent, γ-glycidoxypropyltrimethoxy
Silane (manufactured by Shin-Etsu Chemical)

It is sectional drawing which shows an example of the flip chip type semiconductor device using the sealing material of this invention.

Explanation of symbols

1 Organic substrate 2 Bump 3 Semiconductor chip 4 Underfill material 5 Fillet material

Claims (5)

(A) A liquid epoxy resin which is a liquid epoxy resin which is liquid at room temperature and contains an epoxy group having three or less functional groups in one molecule, and which contains an epoxy resin represented by the following structural formula (4) or (5)

(In the formula, R ⁸ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. X is an integer of 1 to 4.)
(B) An aromatic amine curing agent containing 5% by weight or more of an aromatic amine compound represented by the following general formula (1) is blended with (A) a liquid epoxy resin and (B) an aromatic amine curing agent. Amount in which the molar ratio [(A) / (B)] is 0.7 or more and 1.2 or less

(In the formula, R ^{1 to} R ³ are groups independently selected from a monovalent hydrocarbon group having 1 to 6 carbon atoms, CH ₃ S— and C ₂ H ₅ S—.)
(C) The inorganic filler contains 50 to 500 parts by weight with respect to 100 parts by weight of the total amount of (A) liquid epoxy resin and (B) aromatic amine curing agent , and further has a boiling point of 130 ° C to 250 ° C. A liquid epoxy resin composition comprising 0.5 to 10 parts by weight of the organic solvent (A) with respect to 100 parts by weight of the total amount of (A) liquid epoxy resin and (B) aromatic amine curing agent . The organic solvent is, claim 1 liquid epoxy resin composition wherein the ester organic solvents. The ester organic solvent is represented by the following general formula (2)
^{R 4 COO- [R 5 -O]} n -R 6 (2)
(Wherein R ⁴ and R ⁶ are monovalent hydrocarbon groups having 1 to 6 carbon atoms, R ⁵ is an alkylene group having 1 to 6 carbon atoms, and n is an integer of 0 to 3)
The liquid epoxy resin composition according to claim 2, which is an ester organic solvent represented by the formula: (A) A liquid epoxy resin that is liquid at room temperature and contains an epoxy group having three or less functional groups in one molecule, and includes 25% by weight or more of the epoxy resin represented by the following structural formula (5) in the total epoxy resin Epoxy resin

(In the formula, R ⁸ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. X is an integer of 1 to 4.)
(B) An aromatic amine curing agent containing 5% by weight or more of an aromatic amine compound represented by the following general formula (1) is blended with (A) a liquid epoxy resin and (B) an aromatic amine curing agent. Amount in which the molar ratio [(A) / (B)] is 0.7 or more and 1.2 or less

(In the formula, R ^{1 to} R ³ are groups independently selected from a monovalent hydrocarbon group having 1 to 6 carbon atoms, CH ₃ S— and C ₂ H ₅ S—.)
(C) Liquid epoxy resin composition containing 50 to 500 parts by weight of inorganic filler based on 100 parts by weight of total amount of (A) liquid epoxy resin and (B) aromatic amine curing agent . A flip chip type semiconductor device in which a cured product of the liquid epoxy resin composition according to any one of claims 1 to 4 is sealed as an underfill material.

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