JP2007302759A - Phenolc compound, epoxy resin composition, cured product thereof and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an epoxy resin composition having excellent flame retardance, solder resistance and reliability of moisture resistance and to provide a semiconductor device using the same. <P>SOLUTION: The epoxy resin composition consists essentially of a compound (A) and a phenolic compound (B). The compound (A) has ≥2 epoxy groups in one molecule. The phenolic compound (B) is represented by general formula (1) [wherein, R<SB>1</SB>to R<SB>4</SB>represent each hydrogen, an alkyl group or a phenyl group; and m and n are each 0 or an integer of ≥1]. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a phenol compound, an epoxy resin composition and a cured product thereof, and a semiconductor device.

In recent years, semiconductor elements such as IC and LSI are mainly sealed with an epoxy resin composition and used in semiconductor devices. In recent years, the market trend of electronic devices has been reduced in size, weight and performance, and in order to respond to this trend, the integration of semiconductor elements has been increasing year by year. Further, surface mounting of semiconductor devices has been promoted, and the semiconductor elements have been increased in size with the high integration of semiconductor elements, and the semiconductor devices on which the semiconductor devices are mounted are TSOP (Thin Small Outline Package), TQFP (Thin Quad Flat Flat). Package), BGA (Ball Grid Array), etc., and are becoming surface-mount semiconductor devices.

Conventionally, many curing agents have been used in epoxy resin compositions for such applications. For example, aliphatic or aromatic amine compounds such as diethylenetriamine, isophoronediamine, m-xylylenediamine, m-phenylenediamine, 4,4′-diaminodiphenylsulfone, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, Acid anhydrides such as maleic anhydride, phenol resins such as phenol novolac resin, other polyamides, modified polyamines, imidazoles and the like. However, these curing agents are used to cure various epoxy resins derived from 2,2-bis (4-hydroxyphenyl) propane, phenol novolac resin, orthocresol novolac resin, 4,4′-methylenedianiline, and the like. The resulting epoxy resin composition has advantages and disadvantages in performance, and it is difficult to say that the performance required as a matrix resin can be satisfied.

For the purpose of improving the disadvantages of such matrix resin, as phenol aralkyl resin using phenol as a raw material, use as epoxy resin (for example, see Patent Document 1), use as IC sealant (for example, see Patent Document 2) Etc. are known. However, the performance required for matrix resins for composite materials in recent years is at a higher level in various performances such as heat resistance, mechanical strength, oxidation resistance, moisture resistance, and flame retardancy. . Therefore, a phenol aralkyl resin using phenol as a raw material cannot satisfy these required performances, and further improvement is demanded particularly in terms of flame retardancy.
JP-A-5-117350 JP-A-8-283536

  The present invention provides an epoxy resin composition having excellent flame retardancy and excellent solder resistance and moisture resistance reliability, and a semiconductor device using the same.

  As a result of intensive studies in view of the above problems, the present inventors have found that the above problems can be solved by introducing a biphenyl structure into the structure, and have completed the present invention.

［式（１）中、Ｒ₁〜Ｒ₄は、それぞれ、水素、炭素数１〜４のアルキル基、フェニル基の中から選択される１種を示し、互いに同一であっても異なっていてもよい。ｍおよびｎは0または１以上の整数である。］
［２］ 一般式（１）で表されるフェノール系化合物（Ｂ）を含有することを特徴とする樹脂組成物。

［式（１）中、Ｒ₁〜Ｒ₄は、それぞれ、水素、炭素数１〜４のアルキル基、フェニル基の中から選択される１種を示し、互いに同一であっても異なっていてもよい。ｍおよびｎは0または１以上の整数である。］
［３］ １分子内にエポキシ基を２個以上有する化合物（Ａ）、および一般式（１）で表されるフェノール系化合物（Ｂ）を必須成分とすることを特徴とするエポキシ樹脂組成物。

［式（１）中、Ｒ₁〜Ｒ₄は、それぞれ、水素、炭素数１〜４のアルキル基、フェニル基の中から選択される１種を示し、互いに同一であっても異なっていてもよい。ｍおよびｎは0または１以上の整数である。］
［４］ 充填剤を含む［３］項記載のエポキシ樹脂組成物。
［５］ ［３］又は［４］項に記載のエポキシ樹脂組成物を硬化して得られる樹脂硬化物。
［６］ ［３］又は［４］項に記載のエポキシ樹脂組成物を用いて半導体素子を封止してなる半導体装置。 The above-mentioned subject is achieved by the present invention described in the following [1] to [6].
[1] A phenol compound (B) represented by the general formula (1).

In Expression (1), R ₁ to R ₄ are each hydrogen, an alkyl group having 1 to 4 carbon atoms, represents one selected from among a phenyl group, optionally being the same or different Good. m and n are 0 or an integer of 1 or more. ]
[2] A resin composition comprising a phenolic compound (B) represented by the general formula (1).

In Expression (1), R ₁ to R ₄ are each hydrogen, an alkyl group having 1 to 4 carbon atoms, represents one selected from among a phenyl group, optionally being the same or different Good. m and n are 0 or an integer of 1 or more. ]
[3] An epoxy resin composition comprising, as essential components, a compound (A) having two or more epoxy groups in one molecule and a phenol compound (B) represented by the general formula (1).

In Expression (1), R ₁ to R ₄ are each hydrogen, an alkyl group having 1 to 4 carbon atoms, represents one selected from among a phenyl group, optionally being the same or different Good. m and n are 0 or an integer of 1 or more. ]
[4] The epoxy resin composition according to the item [3], which contains a filler.
[5] A cured resin obtained by curing the epoxy resin composition according to the item [3] or [4].
[6] A semiconductor device formed by sealing a semiconductor element using the epoxy resin composition according to [3] or [4].

  According to the present invention, a semiconductor device encapsulated with the epoxy resin composition is excellent in solder resistance, moisture resistance reliability, and flame retardancy.

  The present invention is a phenol compound (B) represented by the general formula (1), a compound (A) having two or more epoxy groups in one molecule, and a phenol represented by the general formula (1). An epoxy resin composition containing a compound (B) as an essential component, and a semiconductor device in which a semiconductor element is sealed with this epoxy resin composition is excellent in solder resistance, moisture resistance reliability, and flame retardancy. .

Hereinafter, the present invention will be described sequentially.
[Compound (B)]
The phenolic compound (B) of the present invention is obtained by reacting biphenol and phenols with an alkali halide or aralkyl alcohol derivative represented by the general formula (2) in the presence of an acid catalyst in a reaction solvent.

［式（２）中、Ｒは、ハロゲン原子、水酸基又はアルコキシ基である。］

[In Formula (2), R is a halogen atom, a hydroxyl group, or an alkoxy group. ]

The reaction solvent is acetone, methyl ethyl ketone, methyl isobutyl ketone, ethylene glycol,
Examples include, but are not limited to, diethylene glycol, methyl acetate, ethyl acetate, butyl acetate, methyl solosolve, ethyl cellosolve, butyl cellosolve, and mixtures thereof.

  Examples of the phenols include phenol, o-cresol, m-cresol, p-cresol, 2,4-xylenol, 2,6-xylenol, t-butylphenol, o-phenylphenol, m-phenylphenol, and p-phenylphenol. Etc.

  The alkali halide or aralkyl alcohol derivative is a compound in which R is a halogen atom such as chlorine or bromine, a hydroxyl group or an alkoxy group in the general formula (2), and the alkoxy group is preferably a lower alkoxy group having 4 or less carbon atoms.

  The ratio of biphenol and phenols in the reaction is in the range of 5/95 to 60/40, preferably 10/90 to 50/50, by weight. When the biphenol is at least the lower limit, the density of the biphenyl structure in the structure is high, and a sufficient flame retardant effect can be obtained. Moreover, by making it into the said upper limit or less, the crystallinity of the obtained compound can be suppressed and the softening point and the viscosity at the time of melting can be restrained low, and it is preferable.

  In the reaction of the alkali halide or aralkyl alcohol derivative represented by the general formula (2) with biphenol and phenol, 1 mol or more and 20 mol or less, preferably 1.5 mol of biphenol and phenol are used per 1 mol of the alkali halide or aralkyl alcohol derivative. It is heated and reacted in the presence of an acid catalyst in a solvent at 10 mol or less. As the amount of biphenol and phenols used increases, the amount of unreacted biphenol increases. By setting the amount to the lower limit or more, an increase in molecular weight can be suppressed, and the softening point and viscosity at the time of melting can be suppressed low.

  The reaction temperature is preferably 110 ° C. or higher. When the reaction temperature is lower than 110 ° C., the reaction rate becomes slow. In order to shorten the reaction time, it is more desirable to set the reaction temperature within the range of 130 to 250 ° C, and further within the range of 130 to 180 ° C. The reaction time is affected by the reaction temperature, but is about 1 to 30 hours.

  Examples of the acid catalyst include inorganic or organic acids, such as mineral acids such as hydrochloric acid and sulfuric acid, Friedel-Crafts type catalysts such as zinc chloride and ferric chloride, methanesulfonic acid, p-toluenesulfonic acid, dimethylsulfuric acid, diethyl Sulfuric acid esters such as sulfuric acid can be used alone or in combination.

  The amount of the catalyst used is about 0.0001 to 10 parts by weight, preferably about 0.001 to 1 part by weight, based on the total amount of biphenol and phenols and alkali halide or aralkyl alcohol derivative.

[Compound (A)]
The compound (A) having two or more epoxy groups in one molecule used in the present invention is not limited as long as it has two or more epoxy groups in one molecule.
Examples of the compound (A) include bisphenol type epoxy resins such as bisphenol A type epoxy resins and bisphenol F type epoxy resins, biphenyl type epoxy resins, biphenyl aralkyl type epoxy resins, stilbene type epoxy resins, phenol novolac type epoxy resins, Epoxy resins produced by reacting epichlorohydrin with hydroxyl groups such as phenols, naphthols and phenolic resins, such as cresol novolac type epoxy resins, naphthalene type epoxy resins, dicyclopentadiene type epoxy resins and dihydroxybenzene type epoxy resins, Other examples include alicyclic epoxy resins obtained by oxidizing olefins with peracids and epoxidizing, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, etc. It can be used in combination of at least Chino one or.

Among these, as the compound (A), it is particularly preferable to use a compound mainly composed of one or both of a biphenyl type epoxy resin and a biphenyl aralkyl type epoxy resin. Thereby, fluidity at the time of molding of the epoxy resin composition (for example, at the time of manufacturing a semiconductor device, etc.) is improved, and solder crack resistance of the obtained semiconductor device is further improved.
Here, “improvement in resistance to solder cracks” means that the obtained semiconductor device has defects such as cracks and peeling even when it is exposed to high temperatures in, for example, a solder dipping or solder reflow process. It is difficult to occur.

  The biphenyl type epoxy resin and the biphenyl aralkyl type epoxy resin may have an organic substituent, and examples of the organic substituent include those having 1 to 4 carbon atoms such as hydrogen, methyl group, ethyl group, propyl group, and hexyl group. An alkyl group or a phenyl group is selected, and among these substituents, a hydrogen atom or a methyl group is particularly preferable. Thereby, the melt viscosity of the epoxy resin composition is lowered, and the handling thereof becomes easy, for example, at the time of manufacturing a semiconductor device. In addition, since the water absorption of the cured product is reduced, the obtained semiconductor device is preferably prevented from deterioration over time (for example, occurrence of disconnection) of the internal members, and the moisture resistance reliability is further improved.

Another resin can be mix | blended with the phenol type compound (B) of this invention, and a resin composition can be formed. In particular, an epoxy resin composition suitable for semiconductor encapsulation can be formed by blending a compound (A) having two or more epoxy groups in one molecule and a phenolic compound (B).
The amount of the phenolic compound (B) with respect to the compound (A) having two or more epoxy groups in one molecule is not particularly limited, but usually the active hydrogen of the phenol resin is 0.5 to the epoxy equivalent of the epoxy resin. It may be used in such an amount that it is -1.5, preferably 0.8-1.2 equivalent.

  As the filler used in the present invention, those generally used for sealing materials can be used. Examples thereof include silica such as fused silica and crystalline silica, alumina, talc, calcium carbonate, clay, mica and the like. Among these, fused silica is preferable, and the particle shape is preferably spherical. More preferred as the filler is 1 to 100 μm spherical silica. Thereby, while reducing the moisture absorption rate of hardened | cured material, a linear expansion coefficient can be reduced.

  As a compounding quantity of the filler in this invention, it is 200-2400 weight part per 100 weight part of total amounts of the compound (A) which has 2 or more of epoxy groups in 1 molecule, and a phenolic compound (B). It is preferable.

  In addition to the above components, the epoxy resin composition of the present invention, if necessary, for example, a coupling agent such as γ-glycidoxypropyltrimethoxysilane, a colorant such as carbon black, a silicone oil, Various additives such as low stress components such as silicone rubber, natural wax, synthetic wax, higher fatty acids or metal salts thereof, mold release agents such as paraffin, and antioxidants can be added.

  The epoxy resin composition of the present invention is filled with the compound (A) having two or more epoxy groups in one molecule and the phenolic compound (B) represented by the general formula (1) as necessary. The material and other various additives are mixed at room temperature using a mixer, and these mixtures are obtained by heating and kneading using a kneader such as a hot roll and a heating kneader, followed by cooling and pulverization.

The semiconductor device of the present invention is obtained by curing and molding the epoxy resin composition containing the filler obtained above as a molding resin by a molding method such as transfer molding, compression molding, or injection molding. Is obtained by sealing.
The semiconductor device of the present invention thus obtained is excellent in solder resistance, moisture resistance reliability, high temperature storage property, and flame retardancy.

The preferred embodiments of the phenolic compound, the epoxy resin composition, and the semiconductor device of the present invention have been described above, but the present invention is not limited thereto.
EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example, this invention is not limited to this.

[Synthesis Example of Compound (B)]
Although the synthesis example of a compound (B) is shown below, it is not necessarily limited to this method, reaction temperature, and reaction time.

[Compound B-1]
In a reactor equipped with a stirrer, a thermometer and a condenser, 271.7 g (1.46 mol) of biphenol, 1085.5 g (11.5 mol) of phenol, 431.6 g (2.60 mol) of paraxylene glycol dimethyl ether and After 1755 g of butyl cellosolve was added and 1.4 g of diethyl sulfuric acid was added, the reaction was continued for a period of time while maintaining the reaction temperature at 175 ° C. Meanwhile, the methanol produced was distilled off. After completion of the reaction, unreacted phenol was removed by distillation under reduced pressure to obtain 810.0 g of Compound B-1. The softening point was 79 ° C.

[Compound B-2]
In the synthesis of Compound B-1, 1075.5 g of Compound B-2 was obtained in the same manner as in the synthesis of Compound B-1, except that the amount of paraxylene glycol dimethyl ether charged was changed to 647.6 g (3.90 mol). The softening point was 83 ° C.

[Compound B-3]
In a reactor equipped with a stirrer, a thermometer, and a condenser, 283.2 g (1.52 mol) of biphenol, 1131.6 g (10.5 mol) of o-cresol, and 397.6 g (2.39 mol) of paraxylene glycol dimethyl ether were added. After 1620 g of butyl cellosolve was charged and 1.4 g of diethyl sulfuric acid was added, the reaction was allowed to proceed for a time while maintaining the reaction temperature at 175 ° C. Meanwhile, the methanol produced was distilled off. After completion of the reaction, unreacted o-cresol was removed by distillation under reduced pressure to obtain 1371.5 g of Compound C-1. The softening point was 85 ° C.

Example 1
[Preparation of epoxy resin composition and manufacture of semiconductor device]
In the following manner, an epoxy resin composition containing the compound (B) was prepared, and a semiconductor device was manufactured.

  First, as compound (A), a biphenyl type epoxy resin (YX4000H manufactured by Japan Epoxy Resin Co., Ltd.), as compound (B), compound B-1 obtained by the above-mentioned synthesis, a curing accelerator (DBU: 1,8-diazabicyclo ( 5,4,0) undecene-7), fused spherical silica (average particle size 15 μm) as inorganic filler, and carbon black, carnauba wax, silane coupling agent (A-186) as other additives were prepared. .

  Next, biphenyl type epoxy resin: 53 parts by weight, Compound B-1: 47 parts by weight, fused spherical silica: 730 parts by weight, carbon black: 2 parts by weight, carnauba wax: 2 parts by weight, silane coupling agent (A- 186) 3 parts by weight and 1.5 parts by weight of DBU were first mixed at room temperature, then kneaded at 95 ° C. for 8 minutes using a hot roll, and then cooled and ground to obtain an epoxy resin composition.

  Next, using this epoxy resin composition as a mold resin, 8 100-pin TQFP packages (semiconductor devices) and 15 16-pin DIP packages (semiconductor devices) were produced, respectively.

The 100-pin TQFP was manufactured by transfer molding at a mold temperature of 175 ° C., an injection pressure of 7.4 MPa and a curing time of 2 minutes, and post-cured at 175 ° C. for 8 hours.
The package size of the 100-pin TQFP was 14 × 14 mm, the thickness was 1.4 mm, the silicon chip (semiconductor element) size was 8.0 × 8.0 mm, and the lead frame was 42 alloy.

The 16-pin DIP was manufactured by transfer molding at a mold temperature of 175 ° C., an injection pressure of 6.8 MPa and a curing time of 2 minutes, and post-cured at 175 ° C. for 8 hours.
The package size of the 16-pin DIP is 6.4 × 19.8 mm, the thickness is 3.5 mm, the silicon chip (semiconductor element) size is 3.5 × 3.5 mm, and the lead frame is made of 42 alloy. .

  Subsequently, various characteristics were evaluated using the epoxy resin composition and semiconductor device obtained above. The measurement method and test method for each property were as follows. The evaluation results are shown in Table 1.

[Evaluation methods]
(1) Spiral Flow Using a mold for spiral flow measurement according to EMMI-I-66, measurement was performed at a mold temperature of 175 ° C., an injection pressure of 6.86 MPa, and a curing time of 2 minutes. The spiral flow is a fluidity parameter, and the larger the value, the better the fluidity.

(2) Curing torque Using a curast meter (Orientec Co., Ltd., JSR curast meter IVPS type), the torque after 175 ° C. and 45 seconds was measured. The larger this value, the better the curability.

(3) Measurement of glass transition temperature (Tg) Using a transfer molding machine, a test piece (width 2 mm × length 30 mm × thickness 1.0 mm) at a mold temperature of 175 ° C., an injection pressure of 6.86 MPa, and a curing time of 120 seconds. ) And post-cured at 175 ° C. for 4 hours.
For the measurement, a dynamic viscoelasticity measuring device (DMS6100 manufactured by Seiko Instruments Inc.) is used to measure the dynamic viscoelasticity by applying a strain of a frequency of 10 Hz while raising the temperature at a rate of 5 ° C./min. The glass transition temperature (Tg) was determined from the peak value.

(4) Resistance to solder cracks A 100-pin TQFP (Thin Quad Flat Package) semiconductor package was left for 168 hours in an environment of 85 ° C. and 85% relative humidity, and then immersed in a solder bath at 260 ° C. for 10 seconds. . External cracks were observed with a microscope, and the crack generation rate [(number of crack generation packages) / (total number of packages) × 100] was displayed in%. Further, the ratio of the peeled area between the chip and the cured product of the resin composition was measured using an ultrasonic flaw detector, and the peel rate [(peeled area) / (chip area) × 100] The average value was calculated and expressed in%. The smaller the number of cracks and the peeling rate, the better the solder crack resistance.

(5) Moisture resistance reliability A 16-pin DIP (Dual Inline Package) semiconductor package was applied to a 16-pin DIP with a voltage of 20 V in water vapor at 125 ° C. and a relative humidity of 100%, and the disconnection failure was examined. Of the 15 packages, the time until 8 or more defects were detected was defined as the defect time. The unit is time. Note that the measurement time was 500 hours at the longest, and when the number of defective packages was less than 8 at that time, the defective time was 500 hours or more. The longer the defect time, the better the moisture resistance reliability.

(6) UL94 flame retardancy Using a transfer molding machine, a test piece (127 mm × 12.7 mm × 1.6 mm thickness) was molded at a mold temperature of 175 ° C., an injection pressure of 6.86 MPa, and a curing time of 120 seconds. After curing at 175 ° C. for 8 hours, measurement was performed according to the UL-94 vertical method to determine flame retardancy.

(Example 2)
An epoxy resin composition was prepared and a semiconductor device was manufactured in the same manner as in Example 1 except that Compound B-2 was used instead of Compound B-1. Each characteristic was evaluated using the obtained epoxy resin composition and semiconductor device. The evaluation results were as shown in Table 1.

(Example 3)
An epoxy resin composition was prepared and a semiconductor device was manufactured in the same manner as in Example 1 except that Compound B-3 was used instead of Compound B-1. Each characteristic was evaluated using the obtained epoxy resin composition and semiconductor device. The evaluation results were as shown in Table 1.

(Comparative Example 1)
In the same manner as in Example 1 except that phenol aralkyl resin (XL-225 manufactured by Mitsui Chemicals, Inc., where the number of repeating units: 3 represents an average value) was used instead of compound B-1, An epoxy resin composition was prepared to manufacture a semiconductor device. Each characteristic was evaluated using the obtained epoxy resin composition and semiconductor device. The evaluation results were as shown in Table 1.

(Comparative Example 2)
An epoxy resin composition was prepared in the same manner as in Example 1 except that a phenol novolac resin (PR-53195, manufactured by Sumitomo Bakelite Co., Ltd.) was used instead of Compound B-1, and a semiconductor device was produced. Each characteristic was evaluated using the obtained epoxy resin composition and semiconductor device. The evaluation results were as shown in Table 1.

As can be seen from the results shown in Table 1, in Examples 1 to 3, all exhibited excellent flame retardancy and sufficient moisture resistance reliability, solder resistance and curability.
On the other hand, Comparative Examples 1 and 2 are excellent in moisture resistance reliability, solder resistance, and curability, but are not sufficiently flame retardant.

  A semiconductor device sealed with a cured product using the epoxy resin composition of the present invention is excellent in flame retardancy, solder resistance, and moisture resistance reliability, and is also useful for a surface-mount type semiconductor device.

Claims (6)

A phenolic compound (B) represented by the general formula (1).

In Expression (1), R ₁ to R ₄ are each hydrogen, an alkyl group having 1 to 4 carbon atoms, represents one selected from among a phenyl group, optionally being the same or different Good. m and n are 0 or an integer of 1 or more. ] A resin composition comprising a phenolic compound (B) represented by the general formula (1).

In Expression (1), R ₁ to R ₄ are each hydrogen, an alkyl group having 1 to 4 carbon atoms, represents one selected from among a phenyl group, optionally being the same or different Good. m and n are 0 or an integer of 1 or more. ] An epoxy resin composition comprising, as essential components, a compound (A) having two or more epoxy groups in one molecule and a phenolic compound (B) represented by the general formula (1).

In Expression (1), R ₁ to R ₄ are each hydrogen, an alkyl group having 1 to 4 carbon atoms, represents one selected from among a phenyl group, optionally being the same or different Good. m and n are 0 or an integer of 1 or more. ] The epoxy resin composition of Claim 3 containing a filler. A cured resin obtained by curing the epoxy resin composition according to claim 3. The semiconductor device formed by sealing a semiconductor element using the epoxy resin composition of Claim 3 or 4.