JP2006233016A - Epoxy resin composition and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an epoxy resin composition for sealing an area packaging type semiconductor making high fluidity compatible with low warpage and solder resistance characteristics and to provide a semiconductor device using the same. <P>SOLUTION: The epoxy resin composition for sealing the area packaging type semiconductor device is characterized as comprising a crystalline epoxy resin (A), a phenol aralkyl resin (B) having a biphenylene skeleton, a curing accelerator (C) having a specific structure, an inorganic filler (D) and a low-stress modifier (E) which is at least one kind selected from silicone rubber particles, silicone resin particles and silicone rubber particles having the surface coated with a silicone resin and having ≥0.3 to ≤5 μm average particle diameter and ≤10 μm maximum particle diameter as essential components. The area packaging type semiconductor device comprises a semiconductor element loaded onto one surface of a substrate and substantially only one surface of the substrate surface side in which the semiconductor element is loaded is sealed with the epoxy resin composition for sealing the area packaging type semiconductor. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an epoxy resin composition for semiconductor encapsulation and a semiconductor device, and in particular, a semiconductor element is mounted on one side of a printed wiring board or a metal lead frame, and only one side of the mounting side is a resin. It is preferably used for a sealed area mounting type semiconductor device.

  In recent years, the trend toward smaller, lighter, and higher performance electronic devices has led to the progress of higher integration of semiconductor elements and the promotion of surface mounting of semiconductor devices. Devices have been developed and are beginning to migrate from conventional semiconductor devices. With the downsizing and thinning of semiconductor devices, there is a demand for further lowering the viscosity and increasing the strength of the epoxy resin composition for sealing. In addition, due to environmental problems, there is an increasing demand for flame retardancy without using a flame retardant such as bromine compounds and antimony oxide. Against such a background, the trend of recent epoxy resin compositions has been a tendency to apply a lower viscosity resin and to mix more inorganic fillers. Also, as a new movement, when mounting semiconductor devices, the use of lead-free solder having a higher melting point than before is increasing. By applying this solder, it is necessary to raise the mounting temperature by about 20 ° C. compared to the conventional case, and there is a problem that the reliability of the semiconductor device after mounting is remarkably lowered compared to the current situation. For these reasons, the demand for improving the reliability of semiconductor devices by increasing the level of epoxy resin composition is acceleratingly strengthening, and it is spurred by low resin viscosity and high inorganic filler filling. .

  Typical area-mounted semiconductor devices are BGA (ball grid array), or CSP (chip scale package) that pursues further miniaturization, but these are surface mounts such as conventional QFP and SOP. This type of semiconductor device was developed to meet the demand for higher pin count and higher speed, which are approaching the limit. As a structure, on one side of a hard circuit board represented by BT resin / copper foil circuit board (bismaleimide / triazine resin / glass cloth board) or a flexible circuit board represented by polyimide resin film / copper foil circuit board. A semiconductor element is mounted, and only the semiconductor element mounting surface, that is, one side of the substrate is molded and sealed with an epoxy resin composition or the like. In addition, solder balls are two-dimensionally formed in parallel on the surface opposite to the semiconductor element mounting surface of the substrate, and are joined to the circuit substrate on which the semiconductor device is mounted. Furthermore, as a substrate on which a semiconductor element is mounted, a structure using a metal substrate such as a lead frame in addition to the organic circuit substrate has been developed.

These area-mounted semiconductor devices have a single-side sealing configuration in which only the semiconductor element mounting surface of the substrate is sealed with an epoxy resin composition and the solder ball forming surface side is not sealed. A metal substrate such as a lead frame may have a sealing resin layer of about several tens of μm on the solder ball forming surface, but a sealing resin layer of about several hundred μm to several mm is formed on the semiconductor element mounting surface. Therefore, it is substantially single-sided sealed. For this reason, these semiconductor devices are affected by the mismatch of thermal expansion / shrinkage between the organic substrate or metal substrate and the cured product of the epoxy resin composition, or by the effect of cure shrinkage during the molding and curing of the epoxy resin composition. Then, warping is likely to occur immediately after molding.
Further, when solder bonding is performed on a circuit board on which these semiconductor devices are mounted, a heating process of 200 ° C. or higher is performed. At this time, warpage of the semiconductor device occurs, and a large number of solder balls do not become flat. A problem arises in that the reliability of electrical bonding is lowered due to floating from the circuit board on which the semiconductor device is mounted.

In a semiconductor device in which only one surface on a substrate is sealed with an epoxy resin composition, in order to reduce warpage, the thermal expansion coefficient of the substrate and the thermal expansion coefficient of a cured product of the epoxy resin composition are brought close to each other. Two methods of reducing the shrinkage of curing at the time of molding and curing the epoxy resin composition are important.
As the substrate, a resin having a high glass transition temperature (hereinafter referred to as Tg) such as BT resin and polyimide resin is widely used in the organic substrate, and these are from around 170 ° C. which is the molding temperature of the epoxy resin composition. Also has a high Tg. Accordingly, in the cooling process from the molding temperature to room temperature, the glass shrinks only in the glass region of the organic substrate, in other words, in the region where the linear expansion coefficient is α1. Therefore, the cured product of the epoxy resin composition is considered to have almost zero warpage if Tg is higher than the molding temperature, α1 is the same as that of the organic substrate, and curing shrinkage upon molding and curing is zero. For this reason, a technique for increasing Tg by combining a multifunctional epoxy resin and a multifunctional phenol resin and adjusting α1 by the blending amount of the inorganic filler has already been proposed. However, the combination of the polyfunctional epoxy resin and the polyfunctional phenol resin has problems such as a decrease in fluidity and deformation of the gold wire.
In a conventional surface mount type semiconductor device such as QFP or SOP, in order to maintain a low viscosity and a high fluidity at the time of molding, a method using a resin having a low melt viscosity (for example, see Patent Document 1), or inorganic. In order to increase the blending amount of the filler, a method of surface-treating the inorganic filler with a silane coupling agent is known (for example, see Patent Document 2). However, many of them satisfy only one of various required characteristics.

In addition, when solder bonding is performed by means of soldering using means such as infrared reflow, vapor phase soldering, or solder dipping, the moisture present in the semiconductor device is high due to moisture absorption from the cured epoxy resin composition and organic substrate. Due to stress caused by rapid vaporization in the semiconductor device, cracks may occur in the semiconductor device, and peeling may occur at the interface between the semiconductor element mounting surface of the organic substrate and the cured product of the epoxy resin composition. Along with lowering stress and moisture absorption of objects, adhesion to organic substrates is also required.
Furthermore, due to mismatch of thermal expansion between the organic substrate and the cured product of the epoxy resin composition, the temperature cycle test, which is a representative example of the reliability test, also shows the interface between the organic substrate and the cured product of the epoxy resin composition. Peeling or cracking occurs.
In order to achieve both temperature cycle resistance and solder resistance, it is necessary to suppress an increase in elastic modulus even in a system in which a large amount of an inorganic filler is blended. As one of the specific methods, conventionally, there has been known a method of adding various low stress modifiers to impart low stress characteristics. However, the conventional low-stress modifier has strong particle cohesion and does not uniformly disperse during kneading, resulting in non-uniform epoxy resin composition and large variation in characteristics. Further, when the aggregate of the low-stress modifier is large, defects such as a decrease in fluidity due to an increase in viscosity in the molten state and a crack occurring from the aggregate during soldering may occur.
In the area mounting type semiconductor sealing epoxy resin composition, there is a demand for a technique that satisfies the reliability by using a resin excellent in high fluidity, low elasticity, and low warpage, and further increasing the blending amount of the inorganic filler.

JP-A-7-130919 (pages 2 to 10) JP-A-8-20673 (pages 2-6)

  The present invention has been made in order to solve the problems of the conventional background art, and the object of the present invention is high fluidity without lowering curability and other characteristics, after molding and after soldering. It is an object of the present invention to provide an epoxy resin composition suitable for area-mounting type semiconductor encapsulation, which is remarkably excellent in low warpage, solder resistance, and temperature cycle resistance, and a semiconductor device using the same.

The present invention
[1] Crystalline epoxy resin (A), phenol resin (B) represented by general formula (1), curing accelerator (C) represented by general formula (2), inorganic filler (D), silicone It is at least one selected from rubber particles, silicone resin particles, and silicone rubber particles whose surfaces are coated with a silicone resin. The average particle size is 0.3 μm or more and 5 μm or less, and the maximum particle size is 10 μm or less. A semiconductor comprising: a stress modifier (E) as an essential component; and the low stress modifier (E) in a proportion of 0.01 wt% to 5 wt% in the total epoxy resin composition. Epoxy resin composition for sealing,

（ただし、上記一般式（１）において、Ｒ１、Ｒ２は水素又は炭素数４以下のアルキル基で互いに同一でも異なっていても良い。ａは０〜４の整数、ｂは０〜４の整数、ｃは０〜３の整数。ｎは平均値で０〜１０の数。）

(However, in the general formula (1), R1 and R2 may be hydrogen or an alkyl group having 4 or less carbon atoms, and may be the same or different. A is an integer of 0 to 4, b is an integer of 0 to 4, c is an integer of 0 to 3. n is an average value of 0 to 10.)

（ただし、上記一般式（２）において、Ｘは水素又は炭素数１〜３のアルキル基、Ｙは水素又はヒドロキシル基を表す。ｍ、ｎは１〜３の整数。）

(However, in the said General formula (2), X represents hydrogen or a C1-C3 alkyl group, Y represents hydrogen or a hydroxyl group. M and n are integers of 1-3.)

[2] The epoxy resin composition for semiconductor encapsulation according to item [1], wherein the inorganic filler (D) is contained in the total epoxy resin composition in a proportion of 85% or more and 95% by weight or less,
[3] The compound (F) in which a hydroxyl group is bonded to each of two or more adjacent carbon atoms constituting an aromatic ring is 0.01% by weight or more and 0.5% by weight or less in the total epoxy resin composition. The epoxy resin composition for semiconductor encapsulation according to claim [1] or [2],
[4] A semiconductor device comprising a semiconductor element sealed with the epoxy resin composition according to any one of [1] to [3],
[5] A semiconductor element is mounted on one side of a substrate, and is used for sealing substantially only one side of the substrate surface on which the semiconductor element is mounted,
Crystalline epoxy resin (A), phenol resin (B) represented by the following general formula (1), curing accelerator (C) represented by the general formula (2), inorganic filler (D), silicone rubber particles And at least one selected from silicone resin particles and silicone rubber particles whose surfaces are coated with a silicone resin, the average particle diameter of which is 0.3 μm or more and 5 μm or less, and the maximum particle diameter is 10 μm or less. A semiconductor encapsulation characterized by comprising a quality agent (E) as an essential component and the low stress modifier (E) in a proportion of 0.01 wt% or more and 5 wt% or less in the total epoxy resin composition. Epoxy resin composition for

（ただし、上記一般式（１）において、Ｒ１、Ｒ２は水素又は炭素数４以下のアルキル基で互いに同一でも異なっていても良い。ａは０〜４の整数、ｂは０〜４の整数、ｃは０〜３の整数。ｎは平均値で０〜１０の数。）

(However, in the general formula (1), R1 and R2 may be hydrogen or an alkyl group having 4 or less carbon atoms, and may be the same or different. A is an integer of 0 to 4, b is an integer of 0 to 4, c is an integer of 0 to 3. n is an average value of 0 to 10.)

（ただし、上記一般式（２）において、Ｘは水素又は炭素数１〜３のアルキル基、Ｙは水素又はヒドロキシル基を表す。ｍ、ｎは１〜３の整数。）

(However, in the said General formula (2), X represents hydrogen or a C1-C3 alkyl group, Y represents hydrogen or a hydroxyl group. M and n are integers of 1-3.)

[6] The epoxy resin composition for semiconductor encapsulation according to item [5], wherein the inorganic filler (D) is contained in the total epoxy resin composition in a proportion of 85% to 95% by weight,
[7] The compound (F) in which a hydroxyl group is bonded to each of two or more adjacent carbon atoms constituting an aromatic ring is 0.01% by weight or more and 0.5% by weight or less in the total epoxy resin composition. The epoxy resin composition for semiconductor encapsulation according to item [5] or [6],
[8] A semiconductor element is mounted on one side of a substrate, and the epoxy resin composition according to any one of [5] to [7] is substantially only on one side of the substrate surface on which the semiconductor element is mounted. Area mounting type semiconductor device characterized by being sealed using,
It is.

  According to the present invention, since a resin composition excellent in all of the high filling, high fluidity, low warpage, solder resistance, and temperature cycle resistance of inorganic fillers that could not be obtained by conventional techniques can be obtained, It is suitable as an area mounting type semiconductor sealing epoxy resin composition and a semiconductor device using the same.

The present invention includes a crystalline epoxy resin, a phenol aralkyl resin having a biphenylene skeleton, a curing accelerator, an inorganic filler, and a specific low-stress modifier having a specific particle size distribution as essential components. In this semiconductor device, it is possible to obtain a remarkable effect that both low warpage and high reliability such as solder resistance can be achieved.
Hereinafter, the present invention will be described in detail.

As the epoxy resin used in the present invention, a crystalline epoxy resin (A) that is solid at room temperature, has excellent handling workability, and has a very low melt viscosity at the time of molding is required. Since the melt viscosity is low, the epoxy resin composition can be highly fluidized and the inorganic filler can be highly filled, so that the moisture resistance can be improved and the linear expansion can be improved, and the properties as a molded product can be improved. can get.
The crystalline epoxy resin (A) includes hydroquinone glycidyl ether, bisphenol A type epoxy resin, bisphenol F type epoxy resin, biphenyl type epoxy resin represented by general formula (3), and stilbene represented by general formula (4). Type epoxy resins and the like, and these may be used alone or in combination of two or more.

（ただし、上記一般式（３）において、Ｒ３〜Ｒ１０は水素又は炭素数４以下のアルキル基で互いに同一でも異なっていても良い。）

(However, in the general formula (3), R3 to R10 may be the same or different from each other with hydrogen or an alkyl group having 4 or less carbon atoms.)

（ただし、上記一般式（４）において、Ｒ１１〜Ｒ２０は水素又は炭素数４以下のアルキル基で互いに同一でも異なっていても良い。）

(However, in the general formula (4), R11 to R20 may be the same or different from each other with hydrogen or an alkyl group having 4 or less carbon atoms.)

Among the biphenyl type epoxy resins of the general formula (3), 4,4′-diglycidylbiphenyl or 3,3 ′, 5,5′-tetramethyl-4,4, which has a balance between workability and practicality. '-Diglycidylbiphenyl and a molten mixture of both are preferred.
Among the stilbene type epoxy resins of the general formula (4), 5-tertiarybutyl-4,4′-glycidyl-2,3 ′, 5′-trimethylstilbene having a balance between workability and practicality, Alternatively, 4,4′-diglycidyl 3,3 ′, 5,5 ′ tetramethylstilbene and a molten mixture of both are preferred.
The crystalline epoxy resin (A) of the present invention can be used in combination with other epoxy resins. When used in combination, the crystalline epoxy resin (A) is preferably at least 10% by weight or more of the total epoxy resin, more preferably 30% by weight or more, and still more preferably 50% by weight or more. As the blending ratio of the crystalline epoxy resin (A) is higher, better fluidity can be obtained. Although it does not specifically limit as an epoxy resin which can be used together, For example, a phenol novolak type epoxy resin, a cresol novolak type epoxy resin, a triphenolmethane type epoxy resin, a phenol aralkyl type epoxy resin (having a phenylene skeleton and a biphenylene skeleton), a naphthol type Examples include epoxy resins, naphthalene-type epoxy resins, alkyl-modified triphenol methane-type epoxy resins, triazine nucleus-containing epoxy resins, dicyclopentadiene-modified phenol-type epoxy resins, and these can be used alone or in combination of two or more. You may use together. It is desirable to use an epoxy resin having a viscosity as low as possible so as not to impair the characteristics of the crystalline epoxy resin (A) having a very low melt viscosity at the time of molding.

（ただし、上記式（５）において、ｎは平均値で０〜１０の数。） The phenol resin (B) represented by the general formula (1) used in the present invention has a hydrophobic and rigid biphenylene skeleton between phenolic hydroxyl groups, and a cured product of an epoxy resin composition using the same. Has low warpage, low moisture absorption, low elastic modulus in the high temperature range exceeding Tg, and excellent adhesion to semiconductor elements, organic substrates, and metal substrates. Moreover, it has the characteristics that it is excellent in flame retardancy and has high heat resistance for a low crosslinking density.
R1 and R2 in the general formula (1) are hydrogen or an alkyl group having 4 or less carbon atoms, a is an integer of 0 to 4, b is an integer of 0 to 4, c is an integer of 0 to 3, and n is an average value of 0. Among these, a phenol resin represented by the formula (5) is preferable from the viewpoint of curability. If the value of n is within the above range, it is possible to suppress a decrease in fluidity of the resin composition at the time of molding due to an increase in the viscosity of the resin, and an inorganic material for further reducing moisture absorption and warping. High filling of the filler can be achieved.

(However, in said Formula (5), n is an average value and the number of 0-10.)

The phenol resin (B) of the general formula (1) of the present invention can be used in combination with other phenol resins. When used in combination, the phenol resin (B) of the general formula (1) is preferably at least 10% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more based on the total phenol resin. The higher the blending ratio of the phenol resin (B) of the general formula (1), the more excellent resin composition can be obtained in terms of low elasticity at low temperatures, low moisture absorption, adhesion and flame resistance. The phenol resin used in combination is not particularly limited, and examples thereof include phenol novolak resin, cresol novolak resin, naphthol aralkyl resin, triphenolmethane resin, terpene modified phenol resin, dicyclopentadiene modified phenol resin, phenol aralkyl resin having a phenylene skeleton, and the like. These may be used alone or in combination of two or more. In order to increase the filling of the inorganic filler, a material having a low viscosity is preferable like the epoxy resin.
The equivalent ratio of the number of epoxy groups of all epoxy resins and the number of phenolic hydroxyl groups of all phenol resins used in the present invention is preferably 0.5 or more and 2 or less, and more preferably 0.7 or more and 1.5 or less. When the equivalent ratio is in the above range, it is possible to suppress a decrease in moisture resistance, curability, and the like.

（ただし、上記一般式（２）において、Ｘは水素又は炭素数１〜３のアルキル基、Ｙは水素又はヒドロキシル基を表す。ｍ、ｎは１〜３の整数。） In this invention, the hardening accelerator (C) represented by General formula (2) is used as a hardening accelerator. The curing accelerator (C) represented by the general formula (2) is prepared by, for example, uniformly mixing an iodinated phenol and a triaromatic substituted phosphine in an organic solvent, and precipitating as an iodonium salt with a nickel catalyst. It can be obtained by uniformly mixing a base with an organic solvent, and adding water to cause precipitation. The curing accelerator (C) represented by the general formula (2) is preferably one in which X is hydrogen or a methyl group and Y is hydrogen or a hydroxyl group. However, it is not limited to these and may be used alone or in combination. When the curing accelerator (C) represented by the general formula (2) is used, the warpage amount of the IC package can be reduced as compared with the conventional curing accelerator. The blending amount of the curing accelerator (C) represented by the general formula (2) is preferably 0.05% by weight or more and 0.3% by weight or less in the total epoxy resin composition. If it is in the said range, the target sclerosis | hardenability and favorable fluidity | liquidity can be obtained.

(However, in the said General formula (2), X represents hydrogen or a C1-C3 alkyl group, Y represents hydrogen or a hydroxyl group. M and n are integers of 1-3.)

  The curing accelerator (C) of the general formula (2) of the present invention can be used in combination with other curing accelerators. When used in combination, the curing accelerator (C) of the general formula (2) is preferably at least 10% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more in the total curing accelerator. The higher the ratio of the curing accelerator (C) of the general formula (2), the higher the effect of reducing the amount of warpage of the IC package. The curing accelerator used in combination is not particularly limited as long as it accelerates the reaction between an epoxy group and a phenolic hydroxyl group. For example, diazabicycloalkene such as 1,8-diazabicyclo (5,4,0) undecene-7 and the like Derivatives, organic phosphines such as triphenylphosphine, methyldiphenylphosphine, tetraphenylphosphonium / tetraphenylborate, tetraphenylphosphonium / tetrabenzoic acid borate, tetraphenylphosphonium / tetranaphthoic acid borate, tetraphenylphosphonium / tetranaphthoyl Examples include tetra-substituted phosphonium and tetra-substituted borates such as oxyborate and tetraphenylphosphonium / tetranaphthyloxyborate. These may be used alone or in combination of two or more. Good.

  As an inorganic filler (D) used for this invention, what is generally used for the epoxy resin composition for semiconductor sealing can be used. For example, fused spherical silica, fused crushed silica, crystalline silica, talc, alumina, titanium white, silicon nitride and the like can be mentioned, and the most suitably used is fused spherical silica. These inorganic fillers may be used alone or in combination. These may be surface-treated with a coupling agent. The shape of the inorganic filler (D) is preferably as spherical as possible and the particle size distribution is broad in order to improve fluidity. The content of the inorganic filler (D) used in the present invention is preferably 85% by weight or more and 95% by weight or less, more preferably 87% by weight or more and 93% by weight or less in the total epoxy resin composition. It is. When the content of the inorganic filler (D) is in the above range, a resin composition having low hygroscopicity, low thermal expansion, sufficient solder resistance and good warpage characteristics is obtained, and fluidity is lowered. It is possible to suppress the occurrence of defective filling during molding or the occurrence of inconvenience such as deformation of the gold wire in the semiconductor device due to high viscosity.

In the present invention, it is at least one selected from silicone rubber particles, silicone resin particles and silicone rubber particles whose surfaces are coated with a silicone resin, the average particle size is 0.3 μm or more and 5 μm or less, and the maximum particle size is It is essential to use the low-stress modifier (E) having a size of 10 μm or less in a proportion of 0.01 wt% or more and 5 wt% or less in the entire epoxy resin composition. When the average particle size is within the above range, the dispersibility of the low-stress modifier (E) does not decrease and the fluidity of the epoxy resin composition does not decrease, and sufficient low-stress properties are exhibited. can do. Moreover, the fall of low stress property can be suppressed as the largest particle size is in the said range. Further, when the blending amount of the low stress modifier (E) is within the above range, it is possible to suppress a decrease in low stress property, or a decrease in solder resistance due to a decrease in strength of a cured product or an increase in water absorption. .
The average particle size of the low stress modifier (E) in the present invention is preferably measured with a laser diffraction type particle size distribution measuring device or the like, for example, a laser diffraction type particle size distribution measuring device SALD- manufactured by Shimadzu Corporation. 7000 or the like can be used.

As a method for producing a silicone rubber which is a low stress modifier (E) used in the present invention, an organopolysiloxane is usually obtained by polymerizing an organochlorosilane such as methylchlorosilane, trimethyltrichlorosilane, or dimethyldichlorosilane. It is not limited to these. The silicone resin has a basic skeleton having a structure in which organopolysiloxane is three-dimensionally crosslinked. It is also possible to coat the surface of the silicone rubber particles with a silicone resin.
Various functional groups can be introduced into these structures. Examples of functional groups that can be introduced include epoxy groups, amino groups, methoxy groups, phenyl groups, carboxyl groups, hydroxyl groups, alkyl groups, vinyl groups, mercapto groups, and the like. However, it is not limited to these.
In the present invention, other low stress modifiers may be added in combination as long as the characteristics are not impaired. Examples of other low stress modifiers that can be used in combination include butadiene styrene rubber, butadiene acrylonitrile rubber, polyurethane rubber, polyisoprene rubber, acrylic rubber, fluororubber, liquid organopolysiloxane, and liquid synthetic rubber such as liquid polybutadiene. However, it is not limited to these.

  The compound (F) in which a hydroxyl group is bonded to each of two or more adjacent carbon atoms constituting the aromatic ring that can be used in the present invention (hereinafter referred to as compound (F)) is the melt viscosity of the epoxy resin composition. And has the effect of improving fluidity. As the compound (F), a compound represented by the formula (6) or the formula (7) is preferable, and examples thereof include catechol, 1,2-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, and derivatives thereof. Of these, compounds (1,2-dihydroxynaphthalene, 2,3-dihydroxynaphthalene and derivatives thereof) in which the mother nucleus is a naphthalene ring are more preferred from the viewpoint of ease of control and low volatility. Two or more of these compounds (F) may be used in combination. The compounding amount of the compound (F) is preferably 0.01% by weight or more and 0.5% by weight or less, more preferably 0.02% by weight or more and 0.3% by weight or less in the total epoxy resin composition. When the compounding amount of the compound (F) is within the above range, it is possible to obtain the expected viscosity characteristics and flow characteristics, and to suppress the decrease in the curability of the epoxy resin composition and the decrease in the physical properties of the cured product. it can.

（ただし、上記式（６）において、Ｒ２１、Ｒ２５はどちらか一方が水酸基であり、片方が水酸基のとき他方は水素又は水酸基以外の置換基、Ｒ２２、Ｒ２３、Ｒ２４は水素、水酸基又は水酸基以外の置換基。）

(However, in the above formula (6), one of R21 and R25 is a hydroxyl group, and when one is a hydroxyl group, the other is a substituent other than hydrogen or hydroxyl group, and R22, R23 and R24 are other than hydrogen, hydroxyl group or hydroxyl group. Substituent.)

（ただし、上記式（７）において、Ｒ２６、Ｒ３２はどちらか一方が水酸基であり、片方が水酸基のとき他方は水素又は水酸基以外の置換基、Ｒ２７、Ｒ２８、Ｒ２９、Ｒ３０、Ｒ３１は水素、水酸基又は水酸基以外の置換基。）

(In the above formula (7), one of R26 and R32 is a hydroxyl group, and when one is a hydroxyl group, the other is hydrogen or a substituent other than a hydroxyl group, and R27, R28, R29, R30, and R31 are hydrogen, hydroxyl group. Or a substituent other than a hydroxyl group.)

  In addition to the components (A) to (F), the epoxy resin composition of the present invention includes silane coupling agents such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, vinyl silane, and titanate coupling as necessary. Agents, coupling agents such as aluminum coupling agents, aluminum / zirconium coupling agents, natural waxes such as carnauba wax, synthetic waxes such as polyethylene wax, higher fatty acids such as stearic acid and zinc stearate and metal salts thereof, paraffins, etc. Release agents, colorants such as carbon black and bengara, flame retardants such as brominated epoxy resin, antimony trioxide, aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate, phosphazene, bismuth oxide hydrate, etc. Inorganic ion exchange Body, various additives such as an antioxidant can be appropriately blended.

  In the epoxy resin composition of the present invention, the components (A) to (F) and other additives are mixed at room temperature using a mixer or the like, heated and kneaded with a kneader such as a roll, kneader, or extruder, and cooled. Obtained by post-grinding.

  In order to seal an electronic component such as a semiconductor element and manufacture a semiconductor device using the epoxy resin composition of the present invention, it can be cured by a conventional molding method such as transfer molding, compression molding, injection molding, etc. Good. As other semiconductor device manufacturing methods, known methods can be used.

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. The blending ratio is parts by weight.
Example 1
Epoxy resin 1: biphenyl type epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd., YX4000K, melting point 105 ° C., epoxy equivalent 185) 4.33 parts by weight Phenol resin 1: phenol aralkyl resin having biphenylene skeleton (manufactured by Meiwa Kasei Co., Ltd.) MEH7851SS, softening point 65 ° C., hydroxyl group equivalent 203) 4.75 parts by weight

Curing accelerator: Curing accelerator represented by formula (8) 0.22 parts by weight

Fused spherical silica (average particle size 30 μm) 89.00 parts by weight Low stress modifier 1: Low stress modifier in which silicone rubber surface is coated with silicone resin (average particle size 4 μm, maximum particle size 9 μm) 1.00 Part by weight γ-glycidylpropyltrimethoxysilane 0.20 part by weight Carnauba wax 0.20 part by weight Carbon black 0.30 part by weight was mixed with a mixer, and then using two rolls with surface temperatures of 90 ° C and 45 ° C. The mixture was kneaded, cooled and pulverized to obtain an epoxy resin composition. The obtained epoxy resin composition was evaluated by the following methods. The results are shown in Table 1.

Evaluation method Spiral flow: Using a transfer molding machine, an epoxy resin composition in a spiral flow measurement mold according to EMMI-1-66 under conditions of a mold temperature of 175 ° C., an injection pressure of 6.9 MPa, and a curing time of 120 seconds. The material was injected and the flow length was measured. The unit is cm.

  Bending strength: After using a transfer molding machine to mold a test piece (80 mm × 10 mm × 4 mm) at a mold temperature of 175 ° C., an injection pressure of 9.8 MPa, and a curing time of 2 minutes, and post-curing at 175 ° C. for 4 hours. The bending strength at 25 ° C. and 260 ° C. was measured according to JIS K 6911. The unit is MPa.

  Flexural modulus: Using a transfer molding machine, a test piece (80 mm × 10 mm × 4 mm) was molded at a mold temperature of 175 ° C., an injection pressure of 9.8 MPa, and a curing time of 2 minutes, and post-cured at 175 ° C. for 4 hours. Thereafter, the flexural modulus at 25 ° C. and 260 ° C. was measured according to JIS K 6911. The unit is MPa.

  Package warpage: Using a transfer molding machine, mold temperature is 175 ° C., injection pressure is 6.9 MPa, curing time is 2 minutes, 352 pin BGA (substrate is bismaleimide / triazine resin / glass cloth substrate with a thickness of 0.56 mm, The package size is 30 mm x 30 mm, the thickness is 1.17 mm, the semiconductor element size is 10 mm x 10 mm, the thickness is 0.35 mm, and the bonding pad between the semiconductor element and the circuit board is bonded with a 25 μm diameter gold wire) And post-cured at 175 ° C. for 2 hours to obtain a sample. After each of the 10 packages obtained was cooled to room temperature, the displacement in the height direction was measured in a diagonal direction from the gate of the package using a surface roughness meter, and the value with the largest variation difference was taken as the amount of warpage. The unit is μm.

  Gold wire deformation rate: A 352-pin BGA package molded by evaluation of the amount of warpage of the package was observed with a soft X-ray fluoroscope, and the deformation rate of the gold wire was expressed as a ratio of (flow amount) / (gold wire length). Units%.

  Solder resistance: A 352-pin BGA package molded in the same manner as the evaluation of the amount of warpage of the package was post-cured at 175 ° C. for 2 hours. After 168 hours of treatment for 168 hours or in an environment of 85 ° C. and 60% relative humidity, IR reflow treatment (at 255 ° C. or higher for 10 seconds) at a peak temperature of 260 ° C. was performed. The presence or absence of internal peeling and cracks after the treatment was observed with an ultrasonic flaw detector, and the number of defective packages was counted. When the number of defective packages was n, it was displayed as n / 10.

  Thermal cycle resistance: A 352-pin BGA package molded in the same manner as the evaluation of the amount of warpage of the package was post-cured at 175 ° C. for 2 hours, and 10 obtained packages were −65 ° C./30 minutes ← → 150 ° C. / The treatment was repeated in an environment of 30 minutes, and the presence or absence of external cracks was observed every 100 hours. The time when external cracks occurred in 50% or more of the obtained packages was measured and indicated as “50% defect occurrence time”. The unit is hr.

Examples 2-13, Comparative Examples 1-4
According to the composition of Tables 1, 2 and 3, an epoxy resin composition was obtained in the same manner as in Example 1 and evaluated in the same manner. These evaluation results are shown in Tables 1, 2 and 3.
Components used in Examples other than Example 1 are shown below.
Epoxy resin 2: phenol aralkyl type epoxy resin having a biphenylene skeleton (manufactured by Nippon Kayaku Co., Ltd., NC3000, softening point 60 ° C., epoxy equivalent 276)
Phenol resin 2: Phenol aralkyl resin having a phenylene skeleton (Mitsui Chemicals, XLC-LL, softening point 75 ° C., hydroxyl equivalent 175)
Phenol resin 3: phenol novolac resin (softening point 80 ° C., hydroxyl group equivalent 105)
Low stress modifier 2: silicone resin particles (average particle size 1 μm, maximum particle size 7 μm)
Low stress modifier 3: silicone rubber particles (average particle size 15 μm, maximum particle size 30 μm)
2,3-dihydroxynaphthalene (reagent)
1,2-dihydroxynaphthalene (reagent)
Catechol (reagent)
γ-mercaptopropyltrimethoxysilane

  The epoxy resin composition for semiconductor encapsulation of the present invention is excellent in high fluidity, low warpage, solder resistance, and temperature cycle resistance, and is suitable for area mounting type semiconductor devices and the like that require these characteristics. Application is useful.

Claims (8)

Crystalline epoxy resin (A), phenol resin (B) represented by general formula (1), curing accelerator (C) represented by general formula (2), inorganic filler (D), silicone rubber particles, Low stress modification with at least one selected from silicone resin particles and silicone rubber particles whose surface is coated with a silicone resin, an average particle size of 0.3 μm to 5 μm, and a maximum particle size of 10 μm or less For semiconductor encapsulation, characterized in that the agent (E) is an essential component and the low-stress modifier (E) is contained in the total epoxy resin composition in a proportion of 0.01 wt% or more and 5 wt% or less. Epoxy resin composition.

(However, in the general formula (1), R1 and R2 may be hydrogen or an alkyl group having 4 or less carbon atoms, and may be the same or different. A is an integer of 0 to 4, b is an integer of 0 to 4, c is an integer of 0 to 3. n is an average value of 0 to 10.)

(However, in the said General formula (2), X represents hydrogen or a C1-C3 alkyl group, Y represents hydrogen or a hydroxyl group. M and n are integers of 1-3.) The epoxy resin composition for semiconductor encapsulation according to claim 1, wherein the inorganic filler (D) is contained in the total epoxy resin composition in a proportion of 85 wt% or more and 95 wt% or less. The compound (F) in which a hydroxyl group is bonded to each of two or more adjacent carbon atoms constituting an aromatic ring is contained in the total epoxy resin composition in a proportion of 0.01% by weight or more and 0.5% by weight or less. Item 3. The epoxy resin composition for semiconductor encapsulation according to Item 1 or 2. A semiconductor device comprising a semiconductor element sealed with the epoxy resin composition according to claim 1. A semiconductor element is mounted on one side of the substrate, and is used for sealing only substantially one side of the substrate side on which the semiconductor element is mounted,
Crystalline epoxy resin (A), phenol resin (B) represented by the following general formula (1), curing accelerator (C) represented by the general formula (2), inorganic filler (D), silicone rubber particles And at least one selected from silicone resin particles and silicone rubber particles whose surfaces are coated with a silicone resin, the average particle diameter of which is 0.3 μm or more and 5 μm or less, and the maximum particle diameter is 10 μm or less. A semiconductor encapsulation characterized by comprising a quality agent (E) as an essential component and the low stress modifier (E) in a proportion of 0.01 wt% or more and 5 wt% or less in the total epoxy resin composition. Epoxy resin composition.

(However, in the general formula (1), R1 and R2 may be hydrogen or an alkyl group having 4 or less carbon atoms, and may be the same or different. A is an integer of 0 to 4, b is an integer of 0 to 4, c is an integer of 0 to 3. n is an average value of 0 to 10.)

(However, in the said General formula (2), X represents hydrogen or a C1-C3 alkyl group, Y represents hydrogen or a hydroxyl group. M and n are integers of 1-3.) The epoxy resin composition for semiconductor encapsulation according to claim 5, wherein the inorganic filler (D) is contained in the total epoxy resin composition in a proportion of 85% to 95% by weight. The compound (F) in which a hydroxyl group is bonded to each of two or more adjacent carbon atoms constituting an aromatic ring is contained in the total epoxy resin composition in a proportion of 0.01% by weight or more and 0.5% by weight or less. Item 7. The epoxy resin composition for semiconductor encapsulation according to Item 5 or 6. A semiconductor element is mounted on one side of the substrate, and substantially only one side of the substrate surface side on which the semiconductor element is mounted is sealed with the epoxy resin composition according to any one of claims 5 to 7. An area mounting type semiconductor device.