JP2008235669A - Semiconductor device and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means in which the circumference of a wire (metal wire or copper wire) is covered by a liquid resinous composition that is cured and contains few conductive foreign objects, and an electric short circuit failure does not occur caused by the conductive foreign objects. <P>SOLUTION: The semiconductor device has a semiconductor element 2 connected by a metal lead frame's inner lead or an organic circuit board 1's circuit and a wire 5, wherein the circumference of the wire 5 is sealed by a liquid resinous composition 6 that is cured, and is further sealed from above by a hardened material 7 out of a solid resinous composition. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a resin-encapsulated semiconductor device that is less likely to cause a short circuit due to a conductive metal foreign matter caused by an encapsulating resin, and a method for manufacturing the same.

  In a conventional semiconductor device, a semiconductor element (semiconductor chip) is mounted on a metal lead frame or an organic substrate, and the semiconductor element and the inner lead of the lead frame or the circuit of the organic substrate are made of gold wire, copper They are connected by bonding with a metal wire such as a wire. Further, the semiconductor element is resin-sealed with a transfer type epoxy resin composition.

  Recently, miniaturization and high performance of home electric appliances and mobile phones are progressing, and there is a demand for miniaturization, thinning, and high performance of semiconductor devices, and TSOP (Thin Small Outline Package) Metal wire fine pitch has been advanced in QFP (Quad Flat Package), BGA (Ball Grid Array), LGA (Land Grid Array), etc., which are conductive by balls and lands. Some of the latest semiconductor devices have a metal wire pitch of less than 44 μm, which is considered to be 20 μm or less in the future.

  On the other hand, 60 to 90% by mass of the raw material composition of the transfer type semiconductor sealing epoxy resin composition is an inorganic filler having a very high wear resistance. The epoxy resin composition is generally manufactured by mixing, melt-kneading, pulverizing, and tableting processes. In each of these processes, conductive metal foreign matters due to friction and wear of the manufacturing apparatus are mixed. Furthermore, in addition to the above-described manufacturing apparatus, when conductive metal foreign matter exists in the material constituting the composition itself, and carbon black coarse particles blended as a raw material for coloring are mixed There is also. If the semiconductor element is resin-sealed using such an epoxy resin composition for semiconductor encapsulation mixed with such conductive foreign matter, the conductive foreign matter may be sandwiched between metal wires and the like, which may cause an electrical short circuit failure. . In particular, in the narrow pitch semiconductor device as described above, a short circuit failure is likely to occur.

Therefore, in order to reduce the contamination of the conductive metal foreign matter, in the manufacturing process of the epoxy resin composition for semiconductor encapsulation, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 9-173890), a magnet is used to A method for removing conductive metal foreign matter has been proposed.
However, the removal method using the magnet is effective in removing large-sized conductive metal foreign matter and ferromagnetic conductive metal foreign matter, but it does not remove weak magnetic conductive metal foreign matter and carbon black coarse particles. Can't do enough. Moreover, it is difficult to remove foreign substances kneaded into the composition.

Further, in Patent Document 2 (Japanese Patent Laid-Open No. 2006-124478), the conductive metal foreign matter of the epoxy resin composition for semiconductor encapsulation is heated by passing it through the magnetic flux generated by the magnetizer, and the metal foreign matter is detected with an infrared camera. It has been proposed to detect and remove.
However, even with this method, there is a limit to completely removing the conductive metal foreign matter, and coarse particles of carbon black cannot be detected and removed.

  Therefore, the semiconductor device encapsulated with the conventional transfer type epoxy resin composition may cause a short circuit failure, and is uneasy about reliability.

JP-A-9-173890 JP 2006-124478 A

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a semiconductor device that is less likely to cause a short circuit failure due to conductive foreign matter that cannot be achieved by a conventional semiconductor device manufacturing method, and a method for manufacturing the same. And

  As a result of intensive studies to achieve the above object, the present inventor has found that a semiconductor device in which a semiconductor element is connected to an inner lead of a metal lead frame or a circuit of an organic substrate by a wire, the surrounding portion of the wire is (A) a liquid resin. The semiconductor device formed by sealing with the composition and then sealing with the (B) solid resin composition was found to have few short-circuit defects, and the present invention was made.

Accordingly, the present invention provides the following semiconductor device and manufacturing method thereof.
[1] In a semiconductor device in which a semiconductor element is connected to an inner lead of a metal lead frame or a circuit of an organic substrate with a wire, the periphery of the wire is sealed with a cured product of (A) a liquid resin composition, and further (B) A semiconductor device which is sealed with a cured product of a solid resin composition.
[2] The liquid resin composition (A) is characterized in that the amount of metal contained in the composition is 1 ppm or less and substantially does not contain conductive foreign matters having a size of 20 μm or more. [1] The semiconductor device according to [1].
[3] The semiconductor device according to [1] or [2], wherein the liquid resin composition (A) is an epoxy resin composition containing a liquid epoxy resin and a curing agent.
[4] The solid resin composition (B) is an epoxy resin composition comprising an epoxy resin, a phenol resin, a curing accelerator, and an inorganic filler, [1] to [3] The semiconductor device according to any one of the above.
[5] In a method of manufacturing a semiconductor device in which a semiconductor element is connected to an inner lead of a metal lead frame or a circuit of an organic substrate by a wire, after the periphery of the wire is sealed with a cured product of the liquid resin composition (A) And (B) a cured product of the solid resin composition is sealed on the semiconductor device.

  In the semiconductor device of the present invention, since the periphery of the wire (gold wire or copper wire) is covered with a liquid resin composition with little conductive foreign matter, an electrical short circuit failure caused by the conductive foreign matter does not occur. .

  The semiconductor device of the present invention is a semiconductor device in which a semiconductor element is connected to an inner lead of a metal lead frame or a circuit of an organic substrate by a wire, and the periphery of the wire is sealed with a cured product of (A) a liquid resin composition From above, it is sealed with a cured product of (B) a solid resin composition.

  In the liquid resin composition (A), the amount of metal contained in the composition is preferably 1 ppm or less, and it is preferable that the conductive foreign matter having a size of 20 μm or more is substantially not contained. The liquid resin composition is preferably an epoxy resin composition containing (a) a liquid epoxy resin and (b) a curing agent.

  Examples of the liquid epoxy resin (a) used in the liquid resin composition (A) include bisphenol A type epoxy resins, bisphenol F type epoxy resins such as bisphenol F type epoxy resins, phenol novolac type epoxy resins, and cresol novolac type epoxy resins. Examples thereof include novolak-type epoxy resins, naphthalene-type epoxy resins, biphenyl-type epoxy resins, cyclopentadiene-type epoxy resins, and epoxy resins represented by the following formulas, and mixtures thereof. Of these, bisphenol A type epoxy resins and bisphenol F type epoxy resins are preferred.

  Here, R is a monovalent hydrocarbon group having 1 to 20, preferably 1 to 10, more preferably 1 to 3 carbon atoms, such as an alkyl group such as a methyl group, an ethyl group or a propyl group, a vinyl group, Examples include alkenyl groups such as allyl groups. N is an integer of 1 to 4, particularly 1 or 2.

  The liquid epoxy resin (a) is liquid at room temperature. Specifically, the viscosity at 25 ° C. is 1 to 10000 mPa · s, particularly 1 to 1000 mPa · s, as measured by the method defined in JIS K-7117. It is preferable that it is s.

  Although it does not specifically limit as a hardening | curing agent (b) used for a liquid resin composition (A), An amine type, a polymercaptan type, an imidazole type, an acid anhydride type, dicyandiamide, etc. are mentioned. Preferably, amine curing agents and acid anhydride curing agents are used. As the amine curing agent, at least one aromatic amine compound represented by the following general formulas (1) to (4) is preferable.

（式中、Ｒ¹〜Ｒ⁴は独立に炭素数１〜６の一価炭化水素基、ＣＨ₃Ｓ−及びＣ₂Ｈ₅Ｓ−から選ばれる基である。）

(In the formula, R ^{1 to} R ⁴ are groups independently selected from a monovalent hydrocarbon group having 1 to 6 carbon atoms, CH ₃ S— and C ₂ H ₅ S—.)

In the above formula, the monovalent hydrocarbon group of R ^{1 to} R ⁴ is preferably a group having 1 to 6 carbon atoms, particularly 1 to 3 carbon atoms, and preferably a methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group , Alkyl groups such as tert-butyl group and hexyl group, alkenyl groups such as vinyl group, allyl group, propenyl group, butenyl group and hexenyl group, phenyl group, etc., or part or all of hydrogen atoms of these hydrocarbon groups And halogen-substituted monovalent hydrocarbon groups such as a fluoromethyl group, a bromoethyl group, and a trifluoropropyl group, which are substituted with a halogen atom such as chlorine, fluorine, or bromine.

  The aromatic amine-based curing agent is usually solid at normal temperature, and if blended as it is, the resin viscosity increases and the workability is remarkably deteriorated. Therefore, it is preferable to melt and mix at a temperature that does not react with the epoxy resin. That is, it is desirable to melt and mix with the epoxy resin at a temperature range of 70 to 150 ° C. for 1 to 2 hours in a blending amount described later. If the mixing temperature is less than 70 ° C, the aromatic amine curing agent may not be sufficiently compatible, and if it exceeds 150 ° C, it may react with the epoxy resin and increase the viscosity. Also, if the mixing time is less than 1 hour, the aromatic amine curing agent is not sufficiently compatible and may increase the viscosity, and if it exceeds 2 hours, it may react with the epoxy resin and increase the viscosity. .

  Acid anhydride curing agents include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, methylhymic anhydride, pyromellitic dianhydride, maleated alloocimene, benzophenonetetracarboxylic dianhydride 3,3 ′, 4,4′-biphenyltetrabisbenzophenonetetracarboxylic dianhydride, (3,4-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 3,4-dimethyl-6- (2-methyl-1-propenyl) -1,2,3,6-tetrahydro Phthalic anhydride, 1-isopropyl-4-methyl-bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic anhydride Beauty, etc. and mixtures thereof. In particular, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, 3,4-dimethyl-6- (2-methyl-1-propenyl) -1,2,3,6-tetrahydrophthal Preferred are acid anhydride, 1-isopropyl-4-methyl-bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid anhydride and mixtures thereof. Examples of such a curing agent are commercially available as Ricacid MH700 (manufactured by Shin Nippon Chemical Co., Ltd.), YH306, and YH307 (manufactured by Japan Epoxy Resin Co., Ltd.).

  The blending amount of the (b) curing agent is preferably in the range of 0.7 to 1.2, more preferably an equivalent ratio to the liquid epoxy resin [(a) Liquid epoxy resin / (b) curing agent]. Is in the range of 0.8 to 1.0. When the blending molar ratio is less than the lower limit value, unreacted epoxy groups remain, resulting in a decrease in the glass transition temperature, and the adhesion may be decreased. If the upper limit is exceeded, the cured product becomes hard and brittle, and cracks may occur during reflow or temperature cycling.

  Further, an inorganic filler may be added in order to make the expansion coefficient close to that of the composition (B). In this case, the amount of the inorganic filler is preferably 100 to 800 parts by mass, particularly 120 to 700 parts by mass with respect to 100 parts by mass in total of the epoxy resin and the curing agent. The inorganic filler having a particle diameter of 20 μm or more is preferably 1% by mass or less, particularly preferably 0.5% by mass or less. When the particle size is 20 μm or more and more than 1% by mass, clogging is likely to occur during mesh filtration, and workability may be difficult.

The liquid resin composition (A) can be prepared by mixing and stirring an epoxy resin, a curing agent, and other components as necessary. As a device for mixing, a planetary mixer, a sinky mixer, three Although a roll mill etc. are mentioned, it is not specifically limited. After the above components are uniformly mixed, pressure-filtered with a 20 μm mesh to remove conductive foreign matters is used. Here, the pressurizing condition at the time of pressure filtration is preferably ² kgf / cm ² or less, more preferably 0.5 kgf / cm ² or more and 1.5 kgf / cm ² or less. If the pressure exceeds ² kgf / cm ² , the mesh may be broken, and if it is less than 0.5 kgf / cm ² , the discharge amount is small and there may be a problem in productivity.

  The liquid resin composition thus obtained is substantially free of conductive foreign matters having a size of 20 μm or more, and whether or not conductive foreign matters of 20 μm or more are mixed in the composition It can be detected by the following method. That is, 1 kg of the resin composition is dissolved in 2 L of acetone and stirred with a permeator for 1 hour. After that, it is filtered through a 20 μm mesh, and the residue remaining on the mesh is collected with a 10,000 gauss magnet, and the weight and size are measured.

The amount of the conductive foreign matter in the obtained liquid resin composition is preferably 1 ppm or less, more preferably 0.5 ppm or less. Here, the amount of conductive foreign matter in the liquid resin composition can be measured by the following method.
Regarding the amount of conductive foreign matter in the liquid resin composition, the production process of the liquid resin composition has no powder mixing step with a high-speed stirrer such as Henschel like the solid resin composition, and continuous extrusion such as a kneader. Since there is no need to go through a machine, there are very few opportunities for metal foreign matter to enter. Even if it is mixed, it can be reduced to 1 ppm or less by mesh filtration as described above.
If the amount of conductive foreign matter remains in the liquid resin composition more than 1 ppm, or if conductive foreign matter of 20 μm or more is mixed, short circuit failure may not be completely prevented.

  The liquid resin composition (A) is in a liquid state, and according to JIS Z-8803, the measurement temperature is 25 ° C., and the viscosity measured with an E-type viscometer is 10 to 10000 Pa · s, particularly 10 to 1000 Pa · s. preferable.

  Curing of the liquid resin composition (A) is often performed by a potting method at 120 to 180 ° C. for 30 to 120 minutes, particularly 150 ° C. for 60 minutes, but is not limited thereto. . If the curing temperature is too low or the curing time is too short, the liquid resin composition (A) may flow out during the molding of the solid resin composition (B). If the curing temperature is too high or the curing time is too long, the adhesion with the solid resin composition (B) may be deteriorated.

  The solid resin composition (B) is preferably an epoxy resin composition containing an epoxy resin, a phenol resin, a curing accelerator and an inorganic filler.

  The epoxy resin is not particularly limited and may be a commonly used one. For example, a cresol novolak type, a phenol novolak type, a bisphenol A type, a biphenyl type, a triphenylmethane type, a naphthalene type, and the like can be given. These can be used alone or in combination of two or more.

  The said phenol resin has an effect | action as a hardening | curing agent of the said epoxy resin, It does not specifically limit and may be used normally. Examples thereof include phenol novolak, cresol novolak, bisphenol A type novolak, naphthol novolak, and phenol aralkyl resin. These can be used alone or in combination of two or more.

  It is preferable to mix | blend the mixing | blending ratio of the said epoxy resin and a phenol resin so that the hydroxyl group in a phenol resin may be 0.5-1.5 equivalent per 1 equivalent of epoxy groups in an epoxy resin. More preferably, it is 0.8-1.2 equivalent. If the amount of hydroxyl groups in the phenolic resin is too small, sufficient curing may not be obtained under the specified molding conditions, and strength may be reduced. If it is too high, the glass transition temperature of the cured product may be lowered. May affect sex.

  The curing accelerator is not particularly limited, and examples thereof include amine type and phosphorus type. Among them, examples of the amine type include imidazoles such as 2-imidazole, and tertiary amines such as triethanolamine and 1,8-diazabicyclo (5,4,0) undecene-7. Examples of the phosphorus type include triphenylphosphine and tetraphenylphosphonium / tetraphenylborate. These can be used alone or in combination of two or more.

  The blending ratio of the curing accelerator is preferably set to a ratio of 0.1 to 3.0% by mass of the entire resin composition (B). In consideration of moldability and fillability of the resin composition, 0.15 to 0.35% by mass is more preferable. If the blending amount of the curing accelerator is too small, the curing reaction may not proceed sufficiently and the mechanical strength may be reduced. If it is too large, the curing reaction will be too fast, causing molding defects such as unfilling when molding semiconductor components. There is a case.

  As said inorganic filler, what is normally mix | blended with a resin composition can be used. Specific examples include silica such as spherical fused silica, crushed fused silica, crystalline silica, alumina, mullite, silicon nitride, aluminum nitride, boron nitride, titanium oxide, glass fiber, and the like. Among these, silica, particularly spherical fused silica is desirable, and the average particle size thereof is 3 to 30 μm, and the particle size exceeding 75 μm measured by the wet sieving method is 0.2% by mass or less. More desirable from the viewpoint of fluidity. These can be used alone or in combination of two or more.

  In the present invention, the average particle diameter can be obtained by, for example, particle size distribution measurement by a laser light diffraction method or the like, and can be obtained as a weight average value (or median diameter) or the like.

As a compounding quantity of this inorganic filler, it is preferable to set it as 700-1100 mass parts with respect to 100 mass parts of total amounts of an epoxy resin and a phenol resin. If it is less than 700 mass parts, the ratio of resin is high and a linear expansion coefficient may not become the target value. On the other hand, when the amount exceeds 1100 parts by mass, the viscosity becomes high, and there is a possibility that molding cannot be performed.
In the present invention, since the solid resin composition (B) is not in direct contact with the wire, the viscosity of the solid resin composition (B) at the time of molding does not need to be low. In order to prevent warping of the apparatus, it is possible to highly fill the inorganic filler.

  The inorganic filler is preferably blended in advance with a silane coupling agent or the like in order to increase the bonding strength between the resin and the surface of the inorganic filler. Here, the amount of the coupling agent used for the surface treatment and the surface treatment method are not particularly limited.

  Furthermore, in addition to the above components, the resin composition (B) of the present invention includes a flame retardant such as a molybdenum compound, a phosphazene compound, or a brominated epoxy resin, and a flame retardant aid such as antimony trioxide, if necessary. The purpose of the present invention is to add additives such as silane coupling agents such as β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and γ-glycidoxypropyltrimethoxysilane, and release agents such as carnauba wax. It can be used as long as it is not impaired.

  The resin composition (B) of the present invention can be produced by mixing the above-described components and heating and melting them with, for example, a mixing roll or a continuous extruder. After cooling this to room temperature, it is pulverized by known means and tableted as necessary. The resin composition (B) is usually in the form of a powder or a tablet obtained by tableting this.

  The molding method of the resin composition (B) is not particularly limited, but in particular, a transfer molding machine is used, and molding is performed at a high temperature of 160 to 180 ° C. in 40 to 180 seconds. Furthermore, it is preferable to cure at 172 to 178 ° C. after 50 to 90 seconds.

The semiconductor device of the present invention is a semiconductor device in which a semiconductor element is connected to an inner lead of a metal lead frame or a circuit of an organic substrate by a wire, and the periphery of the wire is sealed with a cured product of (A) a liquid resin composition. It is stopped and sealed from above with a cured product of (B) a solid resin composition. The semiconductor device can be first coated with a liquid resin composition (A) and cured, and then sealed with a solid resin composition (B) with a transfer molding machine.
Here, the sealing ratio of the liquid resin composition (A) and the solid resin composition (B) is not particularly limited as long as the entire metal wire is covered with the liquid resin composition (A). .

  In addition, as a coating method of a liquid resin composition (A), a potting method, a dispensing method, etc. are applied. As the curing conditions, the conditions described above can be used. Moreover, the conditions mentioned above can also be employ | adopted for the hardening conditions of a resin composition (B).

Here, the semiconductor device of the present invention will be specifically described with reference to the drawings. FIG. 1 is a cross-sectional view showing the mounting structure of the semiconductor device of the present invention, and nitriding on the organic circuit substrate 1 and the semiconductor element 2. The aluminum wiring 3 covered with silicon, polyimide, or the Low K passivation film 4 is connected by a wire 5, and the liquid resin composition (A) 6 with less conductive foreign matter is hidden so that the wire 5 is hidden. It is coated with a cured product, and further, a cured product of the solid resin composition for transfer molding (B) 7 is sealed thereon.
In addition, wires, such as a gold wire and a copper wire, are used as a wire. Wire diameters of gold wires and copper wires are also miniaturized, and wires having a diameter of less than 20 μm are also applied in the market.

  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. In the following examples, the viscosity is a value at 25 ° C.

[Example 1, Comparative Example 1]
First, each component shown below was prepared.
<Liquid resin composition>
Epoxy resin Bisphenol A type epoxy resin RE303S-L (manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 170, viscosity 30 Pa · s): 65 parts by mass
Curing agent Amine-based curing agent Kayahard AA (manufactured by Nippon Kayaku Co., Ltd., amine number 64, viscosity 20 Pa · s): 35 parts by mass
Spherical silica Average particle size 8 μm, coarse particle amount of 20 μm or more less than 0.1% by mass: 150 parts by mass
Ion trap material DHT-4A-2 (Mg, Al composite oxide, manufactured by Kyowa Chemical): 2 parts by mass
Coupling agent KBM403E (glycidyl type trimethoxysilane, manufactured by Shin-Etsu Chemical): 1 part by mass

The melt viscosity, glass transition temperature (Tg), and linear expansion coefficient of the liquid resin composition are as follows.
Viscosity (25 ° C.): 22 Pa · s
Tg: 100 ° C
Linear expansion coefficient 1:35 ppm
Linear expansion coefficient 2: 115 ppm

In addition, these were measured by the method shown below.
(viscosity)
About each composition, according to JISZ-8803, measurement temperature: 25 degreeC, the sample was set using the E-type viscosity meter, and the value after 2 minutes was measured.
(Glass transition temperature, linear expansion coefficient)
The temperature was raised from room temperature at 10 ° C./min and held at a temperature of 200 to 260 ° C. for 30 seconds to 5 minutes to obtain a cured product. The cured product was cooled to room temperature, a test piece of 5 mm × 5 mm × 15 mm was cut out, and the temperature was raised at 5 ° C. per minute by TMA (thermomechanical analyzer) to measure Tg (glass transition temperature). .
When (Tg-30 ° C) of the cured product is less than 100 ° C, CTE1 (linear expansion coefficient at a temperature of (Tg-30 ° C) or lower) is -30 to 0 ° C, and CTE2 (linear expansion at a temperature higher than Tg). The coefficient was measured at 150 to 180 ° C.
When (Tg-30 ° C) of the cured product was 100 ° C or higher, CTE1 was measured at 50 to 80 ° C, and CTE2 was measured at 200 to 230 ° C.

Detection of conductive metallic foreign matter:
About this obtained composition, the conductive metal foreign material was detected with the above-mentioned conductive metal foreign material detection method.
Conductive metal foreign matter content in 1 kg of composition: 0.5 ppm
Conductive metal foreign matter of 20 μm or more present in 1 kg of the composition: not included

<Solid epoxy resin composition>
Epoxy resin Biphenyl type epoxy resin YX4000 (manufactured by JER, epoxy equivalent 192, melting point 100C): 57 parts by mass
Phenol resin Phenol aralkyl resin MEH7800 (Maywa Kasei, hydroxyl equivalent 170, melting point 83 ° C): 43 parts by mass
Curing accelerator Triphenylphosphine (TPP): 1 part by mass
Inorganic filler a
Spherical fused silica having an average particle diameter of 15 μm and a maximum diameter of 75 μm: 900 parts by mass
Inorganic filler b
Spherical fused silica having an average particle size of 1 μm: 50 parts by mass
Mold release agent Carnauba wax: 2 parts by mass
Coupling agent KBM803 (mercaptotype trimethoxysilane, manufactured by Shin-Etsu Chemical): 2 parts by mass
Pigment <br/> Denka Black: 2 parts by mass

The spiral flow, gel time, melt viscosity, glass transition temperature (Tg), and linear expansion coefficient of the solid epoxy resin composition are as follows.
Spiral flow, 175 ° C: 30 inch
Gelling time, 175 ° C .: 25 seconds melt viscosity, 175 ° C .: 8 Pa · s
Tg: 130 ° C
Linear expansion coefficient 1: 8ppm
Linear expansion coefficient 2: 30 ppm

In addition, these were measured by the method shown below.
(Spiral flow)
Using a mold conforming to the EMMI standard, measurement was performed under conditions of a temperature of 175 ° C., a pressure of 6.9 N / mm ² , and a molding time of 90 seconds.
(Gel time)
The composition was spread thinly on a hot plate heated to 175 ° C., the resin was scraped off with a spatula, and the point at which the resin was peeled off from the hot plate surface was defined as the gel time.
(Melt viscosity)
The minimum melt viscosity when measured by applying a load of 10 kgf at 175 ° C. using a 1 mmφ × 10 mm die using a high-pressure flow tester manufactured by Shimadzu Corporation.
(Glass-transition temperature)
A cured product of 5 mm × 5 mm × 15 mm was molded under the conditions of a temperature of 175 ° C., a molding pressure of 6.9 N / mm ² and a molding time of 120 seconds, and post-cured at 180 ° C. for 4 hours. Thereafter, straight lines were drawn at −55 to 50 ° C. and 150 to 200 ° C. with TMA8140C manufactured by Rigaku Corporation, and the glass transition temperature was determined from the intersection. Temperature rising speed 5 ° C / min.
(Linear expansion coefficient)
A cured product of 5 mm × 5 mm × 15 mm was molded under the conditions of a temperature of 175 ° C., a molding pressure of 6.9 N / mm ² and a molding time of 120 seconds, and post-cured at 180 ° C. for 4 hours. Thereafter, linear expansion coefficients of −55 to 50 ° C. and 150 to 200 ° C. were measured with TMA8140C manufactured by Rigaku Corporation. Temperature rising speed 5 ° C / min.

Detection of conductive metallic foreign matter:
About this obtained composition, the conductive metal foreign material was detected with the above-mentioned conductive metal foreign material detection method.
Conductive metal foreign matter content in 1 kg of composition: 3 ppm
Conductive metal foreign matter of 20 μm or more present in 1 kg of the composition: 30 (maximum diameter 120 μm)

  Using each of the above compositions, a semiconductor device was fabricated and evaluated for short-circuit failure in accordance with the following method in order to confirm short-circuit failure due to mixing of conductive metal foreign matter. The results are shown in Table 1.

[Fabrication of semiconductor devices]
As shown in FIG. 1, the liquid resin composition is hidden so that the wire 5 having a diameter of 20 μm connecting the organic circuit substrate 1 and the aluminum wiring 3 covered with the silicon nitride passivation film 4 on the semiconductor element 2 is hidden. 6 and covered with a dispenser at room temperature, and then cured at 150 ° C. for 30 minutes. Thereafter, the solid epoxy resin composition 7 that was tableted thereon was transfer-molded (conditions: 175 ° C. × 90 seconds), and further post-cured at 175 ° C. × 5 hours to produce a semiconductor device.

  As a comparative example, a semiconductor device that was directly sealed with a solid epoxy resin composition without being covered with a liquid resin composition was produced.

The obtained semiconductor device is an 800-pin PBGA (ball grid array package) shown below.
800-pin PBGA (ball grid array package) type: size 35mm x 35mm x thickness 1.2mm
Semiconductor element size: 10 mm x 10 mm x thickness 1 mm
Terminal pitch: 80 μm, distance between wires: 60 μm

[Short-circuit defect evaluation]
Using 500 semiconductor devices obtained above, the presence or absence of occurrence of short circuit failure was measured. The results are shown in Table 1.

  From the above results, it can be seen that since the amount of conductive metal foreign matter contained in the liquid resin composition used in Example 1 is small, a short circuit failure does not occur and a highly reliable semiconductor device is obtained. On the other hand, in the device that was not coated with the liquid resin composition of Comparative Example 1, a short circuit failure occurred.

It is a schematic sectional drawing which shows an example of the mounting structure of the resin sealing semiconductor device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic circuit board 2 Semiconductor element 3 Al wiring 4 Passivation film 5 Wire 6 Liquid resin composition 7 Solid resin composition for transfer molding

Claims (5)

  In a semiconductor device in which a semiconductor element is connected to an inner lead of a metal lead frame or a circuit of an organic substrate with a wire, the periphery of the wire is sealed with (A) a cured product of a liquid resin composition, and further from above (B ) A semiconductor device which is sealed with a cured product of a solid resin composition.   2. The liquid resin composition (A) is characterized in that the amount of metal contained in the composition is 1 ppm or less and does not substantially contain conductive foreign matters having a size of 20 μm or more. Semiconductor device.   3. The semiconductor device according to claim 1, wherein the liquid resin composition (A) is an epoxy resin composition containing a liquid epoxy resin and a curing agent.   4. The semiconductor device according to claim 1, wherein the solid resin composition (B) is an epoxy resin composition containing an epoxy resin, a phenol resin, a curing accelerator and an inorganic filler. .   In a method of manufacturing a semiconductor device in which a semiconductor element is connected to an inner lead of a metal lead frame or a circuit of an organic substrate with a wire, after the periphery of the wire is sealed with (A) a cured product of a liquid resin composition, (B) A method for producing a semiconductor device, comprising sealing a cured product of a solid resin composition.

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