JP2008111111A - Epoxy resin composition for semiconductor encapsulation and thin semiconductor device - Google Patents

Abstract

An epoxy resin composition for semiconductor encapsulation suitable for an IC card and the like and a thin semiconductor device using the same.
An epoxy resin composition for encapsulating a semiconductor comprising the following components (A), (C), (D), (E), (F) and (G) as essential components. (A) an epoxy resin, (C) an inorganic filler, (D) a phosphorus-containing organic compound curing accelerator having a specific structure, (E) a radical initiator, (F) a compound having two or more maleimide groups in the molecule : (A), (D), (E) and (F) 30 to 60 parts by mass in total of 100 parts by mass, (G) phenol compound having one or more alkenyl groups in the molecule: (F) maleimide The number of moles of alkenyl group per mole of group is 0.1 to 1.0 mole.
[Selection figure] None

Description

  The present invention relates to a thin semiconductor device that has high chemical resistance, particularly resistance to acids and petroleum solvents, and is suitable for an IC card or the like that requires around an automobile engine or security.

  Currently, resin-encapsulated diodes, transistors, ICs, LSIs, and super LSIs are the mainstream of semiconductor devices, but epoxy resins are more formable, adhesive, electrical, mechanical, and moisture resistant than other thermosetting resins. It is common to seal a semiconductor device with an epoxy resin composition because of its excellent properties.

  However, the operating environment of semiconductor devices has become more severe than ever. In the field of electronic parts for automobiles, internal pressure sensors that detect gasoline leaks and electronic control around the engine are being studied, and further improvements in heat resistance and solvent resistance are required.

  The IC card developed in the 1970s is a card that incorporates a semiconductor device (IC chip) to record and calculate information, and the amount of information is several thousand times that of a conventional magnetic stripe card. Information processing is possible, so communication fields such as public telephone prepaid cards, digital broadcast viewing restriction cards, payment methods such as credit cards and cash cards, JR East's "Suica" and JH's ETC cards It has come to be generally used in the market, such as the transportation field. In the administrative field, it has been adopted for citizen cards, Basic Resident Register cards, passports, and so on.

  The reason why the replacement from a magnetic card to an IC card is being promoted in this way is that it is excellent in measures against forgery. Since there is no mechanism to prevent unauthorized reading and writing of information on the magnetic stripe, it can be tampered and copied with a relatively inexpensive device, whereas in the case of an IC card, access control is performed with a semiconductor element, so forgery is not possible. In order to do this, the IC card must be disassembled and the inside must be analyzed using a dedicated IC failure analysis device, so it is said that it is safe as much as it takes time and money.

  However, since the 1990s, examples of successful reading of information necessary for cryptanalysis called a secret key, and semiconductor elements used in commercially available IC cards using an LSI failure analysis device are exposed, and the circuit configuration, internal An example that almost elucidated the operation and physical structure has been reported.

  As a semiconductor failure analysis means, it is necessary to expose the surface of the semiconductor element so that the sealing resin covering the semiconductor element is not physically or chemically damaged. The physical method includes a method of drilling and polishing the sealing resin on the semiconductor element by using a grinder, a drill, or the like, but it is necessary to stop before the exposure. Thereafter, there is a method of soaking in an organic solvent or an inorganic acid to dissolve and remove the remaining sealing resin, a so-called chemical method. These are by hand and have artisan skills. Generally, a method using a commercially available unsealing apparatus for semiconductor failure analysis is used. For example, a type using acid, for example, PS-103A, PS102W / PS102S manufactured by Nippon Scientific, and ES312 manufactured by Nippon Scientific, which is etched with an active ion gas. As the acid, fuming nitric acid, concentrated sulfuric acid, and a mixed acid of sulfuric acid and nitric acid are generally used.

  Considering the spread of IC cards in the future, it can be said that it is indispensable to improve the chemical resistance, especially the security using a highly acidic sealing resin.

  The IC card is an IC card with an external terminal specified by ISO / IEC7816 or JIS6300-X, an IC card without contact type external terminal specified by ISO / IEC10536 or JIS6321, and a proximity specified by ISO / EC14443 or JIS6322. This means an IC card without a type external terminal, or an IC card without a near type external terminal defined by ISO / IEC15693 or JIS6323. The standard thickness of the IC card is 0.76 mm, and the thickness of the semiconductor device used is generally 0.58 mm or less.

  Further, thinning of general semiconductor devices is also progressing, and devices such as TQFP (Thin Quad Flat Package), TSOP (Thin Small Outline Package), and TSSOP (Thin Thin Small Outline Package) are 1.1 mm, BGA ( Devices that are sealed only on one side, such as Ball Grid Array and QFN (Quad Flat Non Lead), are mainly 1.2 mm or less.

  These thin packages are also more susceptible to chemicals than conventional thick devices because the thickness of the sealing resin portion protecting the internal semiconductor elements is also reduced. For example, the resin may swell due to petroleum-based solvents such as gasoline and engine oil, causing electrical and mechanical failure. In addition, it is easy to open with a semiconductor opening device using acid, exposing the semiconductor element used in the IC card, elucidating the circuit configuration, internal operation and physical structure, and using it illegally.

  Conventionally, the glass transition temperature of generally used epoxy sealing resins has a limit of about 200 to 220 ° C. As a resin having a high glass transition temperature, there are super engineering plastics such as polyphenylene sulfite, polyether ether ketone, and polytetrafluoroether, but they are thermoplastic resins and require injection molding at high temperature and high pressure. This is unsuitable for sealing a semiconductor device using a gold wire having a diameter of less than 30 μm. In addition, polyimide also has a high glass transition temperature. However, it is common to use a varnish dissolved in a solvent to a thickness of several tens of μm, and it is difficult to seal with a thickness of 100 μm or more.

In addition, as a well-known document relevant to this invention, there exist the following.
Japanese Patent No. 3295643 JP 2000-17052 A JP 2003-221958 A JP 2003-128757 A

  The present invention has been made in view of the above circumstances, and has a high chemical resistance, particularly resistance to acids and petroleum solvents, and is an epoxy resin for semiconductor encapsulation that is suitable for IC cards and the like that require around the automobile engine and security. It is an object to provide a composition and a thin semiconductor device using the composition.

  As a result of intensive studies to achieve the above object, the present inventor has exposed the surface of the semiconductor element using an opening device if the glass transition temperature obtained by curing the following composition is an epoxy sealing resin having a temperature of 250 ° C. or higher. It was found that the time to make it exponentially extend. It was also found that swelling when immersed in gasoline or oil for a long time can be suppressed. That is, the present invention has found that a thin semiconductor device encapsulated with a cured product of an epoxy resin composition for encapsulating a semiconductor having a high glass transition temperature, preferably 250 ° C. or higher, has excellent chemical resistance. It came to.

（但し、Ｒ¹、Ｒ²、Ｒ³は互いに独立に水素原子、炭素数１〜４のアルキル基、アリール基又はヒドロキシル基、Ｒ⁴〜Ｒ¹⁸は互いに独立に水素原子、又は炭素数１〜４のアルキル基もしくはアルコキシ基である。）
（Ｅ）ラジカル開始剤、
（Ｆ）分子中に２個以上のマレイミド基を有する化合物：（Ａ）、（Ｄ）、（Ｅ）及び（Ｆ）成分の合計１００質量部中３０〜６０質量部、
（Ｇ）分子中に１個以上のアルケニル基を有するフェノール化合物：（Ｆ）マレイミド基１モルに対するアルケニル基のモル数が０．１〜１．０モル。 Accordingly, the present invention provides an epoxy resin composition for encapsulating a semiconductor, characterized in that the following components (A), (C), (D), (E), (F) and (G) are essential components. provide.
(A) epoxy resin,
(C) inorganic filler,
(D) a curing accelerator represented by the following general formula (1),

^{(Wherein, R 1, R 2, R} 3 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group or a hydroxyl group, R ⁴ to R ¹⁸ are each independently a hydrogen atom, or 1 carbon atoms 4 alkyl group or alkoxy group.)
(E) a radical initiator,
(F) Compound having two or more maleimide groups in the molecule: 30 to 60 parts by mass in a total of 100 parts by mass of components (A), (D), (E) and (F),
(G) Phenol compound having one or more alkenyl groups in the molecule: (F) The number of moles of alkenyl groups relative to 1 mole of maleimide groups is 0.1 to 1.0 moles.

In this case, this epoxy resin composition can contain a phenol resin curing agent as the component (B). Moreover, it is preferable that the glass transition temperature of sealing resin obtained by hardening this composition is 250 degreeC or more.
The present invention further relates to a semiconductor device in which a semiconductor element is encapsulated with an encapsulating resin made of a cured product of the above epoxy resin composition for encapsulating a semiconductor, wherein the thickness of the semiconductor device is 1.2 mm or less. A thin semiconductor device is provided in which the thickness of the upper sealing resin layer is 0.10 mm or more and 0.40 mm or less.

  The above-mentioned epoxy resin composition for semiconductor encapsulation is excellent in moldability, has a high glass transition temperature (Tg), and can obtain a cured product having a low dielectric constant. Further, the epoxy resin composition is sealed with a cured product of the epoxy resin composition. The manufactured semiconductor device is excellent in high temperature reliability, moisture resistance reliability, and thermal shock resistance.

  The composition of the present invention can obtain a cured product having a glass transition temperature of 250 ° C. or higher, which has been difficult to achieve with conventional epoxy resin compositions, and has not only excellent heat resistance, but also resistance to acids, petroleum solvents and the like. Excellent chemical properties. Therefore, it is industrially useful in a semiconductor device sealed with a cured product (sealing resin) of the composition, particularly in a thin semiconductor device for in-vehicle use or IC card use.

Hereinafter, the epoxy resin composition that is used in the present invention and preferably provides a sealing resin having a glass transition temperature of 250 ° C. or higher will be described in more detail.
[(A) Epoxy resin]
The (A) component epoxy resin constituting the epoxy resin composition of the present invention is not particularly limited. Common epoxy resins include novolak type epoxy resin, cresol novolac type epoxy resin, triphenolalkane type epoxy resin, aralkyl type epoxy resin, aralkyl type epoxy resin containing biphenyl skeleton, biphenyl type epoxy resin, dicyclopentadiene type epoxy resin , A heterocyclic epoxy resin, a naphthalene ring-containing epoxy resin, a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, a stilbene type epoxy resin, and the like, and one or more of them can be used in combination. Among these, an epoxy resin containing an aromatic ring is preferable, and a polyfunctional epoxy resin containing many epoxy functional groups such as a triphenolalkane type epoxy resin and a cresol novolak type epoxy resin is more preferable.

  The epoxy resin has a hydrolyzable chlorine content of 1,000 ppm or less, particularly 500 ppm or less, and sodium and potassium are each preferably 10 ppm or less. When the hydrolyzable chlorine exceeds 1,000 ppm or the sodium or potassium exceeds 10 ppm, the moisture resistance may deteriorate if the semiconductor device is left under high temperature and high humidity for a long time.

[(B) Curing agent]
(B) Although a hardening | curing agent component is not an essential component in this invention, in the range which does not impair the objective of invention, a common hardening | curing agent may be used. As such a curing agent component, phenol resin is preferable, phenol novolak resin, naphthalene ring-containing phenol resin, aralkyl type phenol resin, triphenol alkane type phenol resin, biphenyl skeleton-containing aralkyl type phenol resin, biphenyl type phenol resin, alicyclic type A phenol resin, a heterocyclic phenol resin, a naphthalene ring-containing phenol resin, bisphenol A, bisphenol F, and the like can be used, and one or more of these can be used in combination.

  It is preferable that the said hardening | curing agent shall make sodium and potassium each 10 ppm or less similarly to an epoxy resin. When sodium or potassium exceeds 10 ppm, moisture resistance may deteriorate if the semiconductor device is left under high temperature and high humidity for a long time.

  The blending ratio of the component (B) to the component (A) is not particularly limited, and may be an effective amount capable of curing an epoxy resin that has been generally employed conventionally, but a phenol resin is used as a curing agent. The molar ratio of the phenolic hydroxyl group contained in the curing agent is usually 0.5 to 1.5 mol, particularly 0.8 to 1.2 mol, relative to 1 mol of the epoxy group contained in the component (A). It is preferable to set it as the range.

[(C) Inorganic filler]
As the inorganic filler (C) blended in the epoxy resin composition of the present invention, those usually blended in the epoxy resin composition can be used. Examples thereof include silicas such as fused silica and crystalline silica cristobalite, alumina, silicon nitride, aluminum nitride, boron nitride, titanium oxide, and glass fiber.

  The average particle size and shape of these inorganic fillers and the filling amount of the inorganic filler are not particularly limited, but the average particle size is 5 to 30 μm, and the filling amount is (A), (F), (G) component and (B). When a component is blended, it is preferably 400 to 1,200 parts by mass, particularly preferably 500 to 1,000 parts by mass with respect to 100 parts by mass as a total of component (B).

  The inorganic filler is preferably blended in advance with a surface treatment with a coupling agent such as a silane coupling agent or a titanate coupling agent in order to increase the bond strength with the resin. Examples of the coupling agent include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, β- (3,4 Epoxy silanes such as -epoxycyclohexyl) ethyltrimethoxysilane; N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane It is preferable to use a silane coupling agent such as an aminosilane such as γ-mercaptopropyltrimethoxysilane. These can be used singly or in combination of two or more. Further, the blending amount of the coupling agent used for the surface treatment and the surface treatment method are not particularly limited.

[(D) Curing accelerator]
In the present invention, a compound represented by the following formula (1) is used to promote the curing reaction between the epoxy resin and the curing agent.

（但し、Ｒ¹、Ｒ²、Ｒ³は互いに独立に水素原子、炭素数１〜４のアルキル基、炭素数６〜１２のフェニル基等のアリール基、又はヒドロキシル基、Ｒ⁴〜Ｒ¹⁸は互いに独立に水素原子、又は炭素数１〜４のアルキル基もしくはアルコキシ基である。）

(However, R ¹ , R ² and R ³ are independently of each other a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group such as a phenyl group having 6 to 12 carbon atoms, or a hydroxyl group, and R ^{4 to} R ¹⁸ are And are independently a hydrogen atom, or an alkyl or alkoxy group having 1 to 4 carbon atoms.)

  That is, triphenylphosphine, tributylphosphine, tri (p-methylphenyl) phosphine, tri (nonylphenyl) phosphine, triphenylphosphine / triphenylborane, tetraphenylphosphine Phosphorus compounds such as tetraphenylborate cannot provide sufficient curability and good moldability cannot be obtained.

Further, tertiary amine compounds such as triethylamine, benzyldimethylamine, α-methylbenzyldimethylamine, 1,8-diazabicyclo (5.4.0) undecene-7, 2-methylimidazole, 2-phenylimidazole, 2- Amine-based curing accelerators such as imidazole compounds such as phenyl-4-methylimidazole reduce moisture resistance reliability.
On the other hand, when the compound of the above formula (1) is used, a molded product excellent in moldability and moisture resistance reliability can be provided.

  When an ester solvent such as ethyl acetate or butyl acetate is used as a method for producing the tertiary phosphine and benzoquinone addition compound represented by the formula (1), columnar crystals of about 10 μm are obtained, and the residual solvent is Very few. Moreover, since the target addition compound of tertiary phosphine and benzoquinones is obtained with high purity, there is no appearance defect due to the volatile component of the curing accelerator, and a cured product excellent in continuous moldability can be obtained, which is preferable. As production conditions in this case, the reaction temperature was 40 ° C. to 90 ° C., preferably 60 ° C. to 80 ° C., and after 0.5 to 3 hours of addition reaction, the resulting precipitate was filtered, and (ester) After washing with a solvent, drying under reduced pressure at 80 ° C. gives an addition reaction product having a purity of 98 to 100%.

  (D) Although the compounding quantity of the hardening accelerator of a component is an effective amount, the compound of the said Formula (1) is 0.1-0.1 with respect to 100 mass parts of total amounts of (A), (F), (G) component. It is preferable to set it as 5 mass parts, especially 0.5-3 mass parts. If the amount is less than 0.1 parts by mass, the curing reaction is slow, and the productivity is likely to decrease. If the amount exceeds 5 parts by mass, the curing reaction is too early and may cause molding defects such as wire flow and unfilling. high.

[(E) Radical initiator]
Although the compound of Formula (1) accelerates the curing reaction between the epoxy resin and the curing agent, the effect is insufficient as an accelerator for the curing reaction of the maleimide compound and the alkenylphenol compound (F) and (G) described later. It is. Therefore, it is necessary to use a radical initiator in combination as a curing accelerator for the maleimide compound and the alkenylphenol compound as the components (F) and (G). Examples of such radical initiators include peroxides such as benzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, dilauroyl peroxide, dibenzoyl peroxide, azoisobutyronitrile, 4,4′- Examples include azo compounds such as azobis (4-cyanovaleric acid) and 2,2′-azobis (2,4-dimethylvaleronitrile). Among them, the temperature for dicumyl peroxide to obtain a half-life of 1 minute. Is preferable because it is close to the transfer molding temperature and has excellent moldability.

The compounding amount of the radical initiator is preferably 0.05 to 3 parts by mass, particularly preferably 0.1 to 1 part by mass with respect to 100 parts by mass of the total amount of the components (A), (F) and (G). If it is less than 0.05 parts by mass, sufficient polymerization reaction may not be obtained within the molding time, and if it exceeds 3 parts by mass, there is a high possibility of causing molding defects such as wire flow due to thickening, unfilled, and storage. There is also a risk that the property will also decrease.
The combined ratio of the compound of formula (1) and the radical initiator is such that the compound of formula (1) / radical initiator is 0.5 to 6, preferably 2 to 3 in terms of mass ratio.

[(F) Compound having maleimide group]
The structure of the compound having two or more maleimide groups in the molecule (F) used in the present invention is not particularly limited, and N, N′-4,4′-diphenylmethane bismaleimide, N, N′— (3,3′-dimethyl-4,4′-diphenylmethane) bismaleimide and the like. As such a maleimide group-containing compound, bismaleimide: BMI (trade name of KAI Kasei Co., Ltd.) represented by the following formula is preferable.

  The amount of the maleimide compound added is preferably 30 to 60 parts by mass, particularly 40 to 50 parts by mass with respect to 100 parts by mass of the total amount of the components (A), (D), (E) and (F). If it is less than 30 parts by mass, the glass transition temperature derived from the matrix of epoxy groups and phenolic hydroxyl groups is inferior, and if it exceeds 60 parts by mass, the fluidity is lowered, causing molding defects such as wire flow. 30-60 mass parts from the balance surface of a semiconductor sealing material characteristic, Especially 40-50 mass parts vicinity is preferable.

[(G) a phenol compound having one or more alkenyl groups in the molecule]
(G) As a phenolic compound having one or more alkenyl groups in the molecule, o, o′-diallyl-bisphenol A, o, o′-di (1-propenyl) -bisphenol A, o-allylphenol novolak resin O- (1-propenyl) phenol novolak resin, tris o-allylphenol alkane type phenol resin, tris o- (1-propenyl) phenol alkane type phenol resin, and the like. In consideration of reactivity with a compound containing a maleimide group, o, o′-di (1-propenyl) -bisphenol A, o- (1-propenyl) phenol novolak resin, o- (1-propenyl) phenolalkane type phenol It is desirable to contain 1-propenyl group, such as resin. This is because cyclization excellent in heat resistance and chemical resistance occurs due to the addition reaction by the aforementioned bismaleimide group and Diels-Alder reaction.

  Examples of the alkenyl group-containing phenol compound include o- (1-propenyl) phenol novolak resin (trade name 1PP-2: manufactured by Gunei Chemical Industry Co., Ltd.) represented by the following formula.

（但し、ｍ＝１〜１００、ｎ＝１〜１００、ｍ＋ｎ＝２〜２００である。）

(However, m = 1 to 100, n = 1 to 100, and m + n = 2 to 200.)

  Although it does not specifically limit as the addition amount of the phenolic compound which has an alkenyl group, In order to obtain a high glass transition temperature, an alkenyl group is 0.1-1.0 mol with respect to 1 mol of maleimide groups of (F) component, Particularly preferably, the amount is 0.2 to 0.5 mol.

[(H) Other ingredients]

  In addition to the above components (A) to (G), the epoxy resin composition for semiconductor encapsulation of the present invention is limited to the range in which the object and effect of the present invention can be expressed, and various additions as necessary. An agent can be blended. For example, thermoplastic resin, thermoplastic elastomer, organic synthetic rubber, low stress agent such as silicone, carnauba wax, higher fatty acid, wax such as synthetic wax, colorant such as carbon black, halogen trap agent, phosphazene compound, molybdenum Flame retardants and additives such as acid zinc compounds can be added and blended.

  Examples of the release agent component include carnauba wax, rice wax, polyethylene, polyethylene oxide, montanic acid, montanic acid and saturated alcohol, 2- (2-hydroxyethylamino) -ethanol, ethylene glycol, glycerin and the like. A certain montan wax; stearic acid, stearic acid ester, stearic acid amide, ethylene bis-stearic acid amide, a copolymer of ethylene and vinyl acetate, etc. are used, and these are used alone or in combination of two or more. be able to.

  The mixing ratio of the release agent is preferably 0.1 to 5 parts by mass, more preferably 0.3 to 4 parts by mass with respect to 100 parts by mass of the total amount of the components (A) and (B).

[Preparation of epoxy resin composition, etc.]
The epoxy resin composition of the present invention is prepared, for example, by blending the above components (A) to (G) and other additives in a predetermined composition ratio, and mixing them sufficiently uniformly by a mixer, a ball mill, etc. Then, a kneader, an extruder, or the like is used to perform a melt mixing treatment, then cooled and solidified, and pulverized to an appropriate size to obtain a molding material.

  In addition, when mixing the composition sufficiently uniformly with a mixer or the like, it is preferable to perform surface treatment or the like in advance with a silane coupling agent or the like as a wetter in order to improve storage stability.

  Here, as the silane coupling agent, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, γ- Methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, N-β (aminoethyl) ) Γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminop Pyrtriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, bis (triethoxypropyl) tetrasulfide, γ-isocyanatopropyltriethoxysilane, etc. Is mentioned. Here, the amount of the silane coupling agent used for the surface treatment and the surface treatment method are not particularly limited.

  The epoxy resin composition of the present invention thus obtained can be effectively used for sealing various semiconductor devices. Examples of the sealing method include a low-pressure transfer molding method. In addition, when hardening and shaping | molding of the epoxy resin composition of this invention, it processes for 30 to 300 second at 150-200 degreeC, for example, and postcure (post-cure) is performed on the conditions for 2 to 16 hours at 180-260 degreeC. In order to obtain a high glass transition temperature, it is desirable to perform post-curing at a high temperature for a long time.

In the semiconductor device encapsulated with the cured product of the resin composition for semiconductor encapsulation of the present invention, the glass transition temperature (Tg) of the encapsulating resin (cured product) is 250 ° C. or higher, preferably 280 ° C. or higher. It is valid. The semiconductor device (semiconductor device thickness 0.58 mm, sealing material thickness 0.30 mm) shown in FIG. 1 was heated to 65 ° C. using a semiconductor opening device PS-103A (manufactured by Nippon Scientific Co., Ltd.). FIG. 2 shows the results of measuring the time until the surface of the semiconductor element sealed with fuming nitric acid (d = 1.52) is exposed. According to this, it can be seen that the opening time (the time until the surface of the semiconductor element is exposed) increases exponentially with the glass transition temperature of the sealing resin.
In FIG. 1, 1 is a glass fiber reinforced epoxy resin substrate, 2 is a semiconductor element, 3 is an adhesive, 4 is a bond wire, and 5 is a sealing resin.
As described above, the semiconductor device according to the present invention having a glass transition temperature (Tg) of the sealing resin of 250 ° C. or higher is suitable for in-vehicle use and security card use because the sealing resin has high chemical resistance. .

  The glass transition temperature in the present invention was measured up to 300 ° C. with a temperature rise of 5 ° C./min and a load of 19.6 mN with a test piece set on a thermal dilatometer. Create a graph of dimensional change and temperature, dimensional change-Temperature at temperature below the inflection point-2 arbitrary temperatures at which the tangent of the temperature curve can be obtained A1, A2, any 2 at which the tangent can be obtained at the temperature above the inflection point Points B1 and B2 were selected, and the intersection of the straight line connecting A1 and A2 and the straight line connecting B1 and B2 was defined as the glass transition temperature.

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

[Examples 1 to 4, Comparative Examples 1 to 6]
The components shown in Tables 1 and 2 were uniformly melt-mixed with two hot rolls, cooled and pulverized to obtain an epoxy resin composition. These compositions were molded under the conditions of 175 ° C., 6.9 N / mm ² , and a molding time of 120 seconds to obtain 5 × 5 × 15 mm test pieces. Each test piece was post-cured under each condition, and then glass transition temperature, acid resistance, and gasoline resistance were measured.

<Glass transition temperature>
The test piece was set on a thermal dilatometer (Rigaku TMA8140C) and measured up to 300 ° C. at a temperature increase of 5 ° C./min and a load of 19.6 mN. Create a graph of dimensional change and temperature, dimensional change-temperature curve tangent at temperatures below the inflection point, any temperature 2 points A1, A2, any tangent above the inflection point temperature 2 Points B1 and B2 were selected, and the intersection of the straight line connecting A1 and A2 and the straight line connecting B1 and B2 was defined as the glass transition temperature. FIG. 3 shows a graph of typical dimensional change and temperature.

<Acid resistance>
The semiconductor device shown in FIG. 1 (semiconductor device thickness 0.58 mm, sealing material thickness 0.30 mm) is used to open the semiconductor device with acid using the semiconductor opening device PS-103A (manufactured by Nippon Scientific Co., Ltd.). Was measured. Conditions were measured for fuming nitric acid heated to 65 ° C. (d = 1.52) and the time until the surface of the semiconductor element sealed with an opening area of 5 × 5 mm was exposed.

<Gasoline resistance>
A molded piece of 100 × 10 × 0.8 mm was molded at 175 ° C. for 90 seconds, post-cured for a predetermined time, immersed in gasoline, and left at 30 ° C. for 1 week. After one week, the change in weight was measured.

(A) Epoxy resin Epoxy resin a: o-cresol novolac type epoxy resin (EOCN1020-65, Nippon Kayaku Co., Ltd., epoxy equivalent 200)
Epoxy resin b: biphenyl type epoxy resin (YX-4000K, manufactured by Japan Epoxy Resin Co., Ltd., epoxy equivalent 190)
Epoxy resin c: biphenyl aralkyl type epoxy resin (NC-3000, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 272)
Epoxy resin d: Triphenolalkane type epoxy resin (EPPN-502H, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 168)

(B) Curing agent curing agent a: phenol novolak resin (DL-92, manufactured by Meiwa Kasei Co., Ltd., phenolic hydroxyl group equivalent 110)
Curing agent b: phenol aralkyl resin (MEH-7800SS, manufactured by Meiwa Kasei Co., Ltd., phenolic hydroxyl group equivalent 175)
Curing agent c: Triphenolalkane type phenol resin (MEH-7500, Meiwa Kasei Co., Ltd., phenolic hydroxyl group equivalent 97)

(C) Inorganic filler: spherical fused silica (manufactured by Tatsumori Co., Ltd., average particle size of 15 μm)
(D) Curing accelerator Curing accelerator a: Compound represented by the following formula

（硬化促進剤ａの製造方法）
トリフェニルホスフィン（北興化学（株）製）８３２．０ｇを酢酸ブチル１８００．０ｇに溶解させ、８０℃で３０分撹拌する。１，４−ベンゾキノン３５２．０ｇ／酢酸ブチル１８００ｇ中溶液を１４５ｇ／分で滴下し、滴下終了後、１時間撹拌し、熟成する。その後、室温まで冷却し、析出物を濾過、洗浄、減圧乾燥し、トリフェニルホスフィンと１，４−ベンゾキノンの付加物９８２．７ｇを得た。
硬化促進剤ｂ：トリフェニルホスフィン（ＴＰＰ、北興化学（株）製）
硬化促進剤ｃ：イミダゾール化合物（２ＰＺ、四国化成（株）製）

(Method for producing curing accelerator a)
832.0 g of triphenylphosphine (manufactured by Hokuko Chemical Co., Ltd.) is dissolved in 1800.0 g of butyl acetate and stirred at 80 ° C. for 30 minutes. A solution in 352.0 g of 1,4-benzoquinone / 1,800 g of butyl acetate is added dropwise at 145 g / min. After completion of the addition, the mixture is stirred for 1 hour and aged. Thereafter, the mixture was cooled to room temperature, and the precipitate was filtered, washed, and dried under reduced pressure to obtain 982.7 g of an adduct of triphenylphosphine and 1,4-benzoquinone.
Curing accelerator b: Triphenylphosphine (TPP, manufactured by Hokuko Chemical Co., Ltd.)
Curing accelerator c: Imidazole compound (2PZ, manufactured by Shikoku Kasei Co., Ltd.)

(E) Radical initiator: Dicumyl peroxide (Park Mill D, manufactured by NOF Corporation)
(F) Maleimide group-containing compound: Bismaleimide represented by the following formula (BMI, manufactured by KAI Kasei Co., Ltd.)

（Ｇ）アルケニル基含有フェノール化合物：下記式で示されるｏ−（１−プロペニル）フェノールノボラック樹脂（１ＰＰ−２、群栄化学（株）製）

(G) Phenol compound containing alkenyl group: o- (1-propenyl) phenol novolak resin represented by the following formula (1PP-2, manufactured by Gunei Chemical Co., Ltd.)

ｍ／ｎ＝１／１

m / n = 1/1

(H) Other additive release agent: Carnauba wax (manufactured by Nikko Fine Products Co., Ltd.)
Carbon black: Denka Black (manufactured by Denki Kagaku Kogyo Co., Ltd.)
Silane coupling agent: γ-glycidoxypropyltrimethoxysilane (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.)

The conceptual diagram of the semiconductor device figure used in the Example is shown. The glass transition temperature and the opening time until the semiconductor element is exposed are shown. The temperature-dimensional change graph (how to obtain the glass transition temperature) is shown.

Claims (4)

An epoxy resin composition for semiconductor encapsulation, comprising the following components (A), (C), (D), (E), (F) and (G) as essential components.
(A) epoxy resin,
(C) inorganic filler,
(D) a curing accelerator represented by the following general formula (1),

^{(Wherein, R 1, R 2, R} 3 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group or a hydroxyl group, R ⁴ to R ¹⁸ are each independently a hydrogen atom, or 1 carbon atoms 4 alkyl group or alkoxy group.)
(E) a radical initiator,
(F) Compound having two or more maleimide groups in the molecule: 30 to 60 parts by mass in a total of 100 parts by mass of components (A), (D), (E) and (F),
(G) Phenol compound having one or more alkenyl groups in the molecule: (F) The number of moles of alkenyl groups relative to 1 mole of maleimide groups is 0.1 to 1.0 moles.   The epoxy resin composition for semiconductor encapsulation according to claim 1, comprising a phenol resin curing agent as component (B).   3. The epoxy resin composition for semiconductor encapsulation according to claim 1, wherein the glass transition temperature of the sealing resin as a curing agent is 250 ° C. or higher.   A semiconductor device in which a semiconductor element is sealed with a sealing resin made of a cured product of an epoxy resin composition for semiconductor sealing according to any one of claims 1 to 3, wherein the thickness of the semiconductor device is 1.2 mm. A thin semiconductor device, wherein the sealing resin layer on the semiconductor element has a thickness of 0.10 mm or more and 0.40 mm or less.

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