JP7274384B2 - Resin composition for semiconductor encapsulation, semiconductor device, and method for manufacturing semiconductor device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a resin composition for semiconductor encapsulation, a semiconductor device, and a method for manufacturing a semiconductor device.

A wire bonding method using thin metal wires such as gold wires is widely applied to connect a semiconductor chip and a substrate. In a single-sided sealing type BGA (Ball grid array) package or the like, wire deformation is likely to occur due to wire thinning and wiring pitch reduction. In order to reduce this wire deformation, the fluidity of the sealing resin is an important factor. By the way, spiral flow, disc flow, and high-flow flow viscosity have been used to evaluate the fluidity of encapsulating resins. In particular, for the high-flow viscosity, which is often used as an indicator of high fluidity of encapsulating resins, the target value differs depending on the type of resin composition.

In Patent Document 1, the stress value “low shear region flow stress” at a shear rate of 1 s ⁻¹ or less is defined as a fluidity evaluation index and used as a fluidity evaluation index for sealing resin.
In Patent Document 2, the fluidity of the epoxy resin composition in the low shear region is evaluated by evaluating the porosity when the epoxy resin composition is cured. It is disclosed to be an indicator of viscosity.
However, according to Non-Patent Document 1, in the mold used for semiconductor encapsulation, the shear rate varies depending on the location, and the shear rate in the cavity, which is the main cause of wire deformation, is 1.0 s ^-1 to 10.0 s It is assumed to be in the range of ^-1 .

JP 2007-232717 A JP 2016-035075 A Tadashi Yoshihara, 5 others, Effect of mold resin on wire flow in resin-sealed IC, Transactions of the Institute of Electronics, Information and Communication Engineers, Vol. J82-C-II No. 1, p. 7-12, '99/1

Compared to Non-Patent Document 1, the shear rate was 10 ³ /s or more when measuring the flow viscosity of Koka method. For this reason, it is difficult to say that the fluidity obtained from the Koka flow viscosity measurement represents the fluidity of the resin composition inside the cavity, which greatly affects wire deformation.

The present invention has been made in view of such circumstances, and a resin composition for semiconductor encapsulation capable of reducing wire deformation during encapsulation of a semiconductor element, and a semiconductor encapsulation resin composition using the resin composition for encapsulation of a semiconductor. An object of the present invention is to provide a semiconductor device and a method for manufacturing the semiconductor device.

As a result of intensive studies by the present inventors to solve the above problems, the present inventors have found a sealing resin composition containing silica having a specific particle size distribution and having a maximum flow stress measured under specific conditions of a specific value or less. found to solve the above problems.
The present invention has been completed based on such findings.

That is, the present disclosure relates to the following.
[1] Contains (A) an epoxy resin, (B) a phenol resin, (C) a curing accelerator and (D) silica, and the (D) silica contains particles having a particle size of 1.5 μm or less at a rate of 46 volumes % or less, and a maximum flow stress of 700 Pa or less at a shear rate of 1 s ^-1 to 10 s ^-1 measured using a rheometer at a temperature of 175°C.
[2] The (D) silica contains (d1) 10 to 46% by volume of particles having a particle size of 1.5 μm or less, and (d2) 5 to 30% by volume of particles having a particle size of more than 1.5 μm and 5 μm or less. %, (d3) 5 to 30% by volume of particles with a particle size of more than 5 μm and 10 μm or less, (d4) 10 to 45% by volume of particles with a particle size of more than 10 μm and 20 μm or less, (d5) a particle size of 20 μm For semiconductor encapsulation according to [1] above, having a particle size distribution in which the proportion of particles with a particle size exceeding 50 μm is 0 to 30% by volume, and (d6) the proportion of particles with a particle size exceeding 50 μm is 0 to 20% by volume. Resin composition.
[3] The resin composition for semiconductor encapsulation according to [1] or [2] above, wherein the softening point of the (A) epoxy resin and/or the softening point of the (B) phenol resin is 120° C. or lower.
[4] A method for manufacturing a semiconductor device, wherein a semiconductor element mounted on a substrate is sealed using the resin composition for semiconductor sealing according to any one of [1] to [3] above.
[5] A substrate, a semiconductor element mounted on the substrate, and a cured product of the resin composition for semiconductor encapsulation according to any one of the above [1] to [3], which is obtained by encapsulating the semiconductor element. and a semiconductor device.

INDUSTRIAL APPLICABILITY According to the present invention, a semiconductor encapsulating resin composition capable of reducing wire deformation during encapsulation of a semiconductor element, a semiconductor device using the semiconductor encapsulating resin composition, and a method for manufacturing the semiconductor device are provided. can do.

The invention will now be described in detail with reference to one embodiment.

<Resin composition for semiconductor encapsulation>
The resin composition for semiconductor encapsulation of the present embodiment (hereinafter also simply referred to as the resin composition for encapsulation) contains (A) an epoxy resin, (B) a phenol resin, (C) a curing accelerator and (D) silica. contains, the (D) silica has a particle size distribution in which the proportion of particles with a particle size of 1.5 μm or less is 46% by volume or less, and is measured using a rheometer at a temperature of 175 ° C., a shear rate of 1 s It is characterized by having a maximum flow stress of 700 Pa or less at ⁻¹ to 10 s ⁻¹ .

By measuring the maximum flow stress of the encapsulating resin composition using a rheometer, the present inventors found that the melting behavior of the resin in the encapsulating resin composition in the region where the shear rate is less than 1 s ⁻¹ is dominant, and it has been found that the flow state of the encapsulating resin composition is well represented in the range of shear rate from 1 s ^-1 to 10 s ^-1 . Furthermore, in the volume-based particle size distribution of silica (D), as the proportion of particles with a particle size of 1.5 μm or less increases, it was found that the flow stress in the region of shear rates from 1 s ⁻¹ to 10 s ⁻¹ increases. .
In the region of shear rate of 0.1 s ⁻¹ or less, the lower the softening temperature (softening point) of the resin component in the sealing resin composition, the smaller the rate of change of flow stress with respect to shear rate.

The encapsulating resin composition of the present embodiment has a maximum flow stress of 700 Pa or less at a shear rate of 1 s ⁻¹ to 10 s ⁻¹ measured at a temperature of 175° C. using a rheometer. If the maximum flow stress exceeds 700 Pa, the wire may be deformed during sealing of the semiconductor element. From this point of view, the maximum flow stress is preferably 650 Pa or less, more preferably 600 Pa or less. The lower limit of the maximum flow stress is preferably 100 Pa, more preferably 120 Pa, from the viewpoint of reflow resistance.
Specifically, the maximum flow stress can be measured by the method described in Examples.
The maximum flow stress can be set to 700 Pa or less by appropriately adjusting the ratio of particles having a particle size of 1.5 μm or less in the volume-based particle size distribution of silica (D) described later.

In a rheometer, the sample to be evaluated is set between two parallel plates, and one of them is rotated or vibrated. Shear stress due to the rotation or vibration acts on the sample, and the resulting strain rate (shear rate) is measured. It is a device that measures the flow stress from the calculation formula. In this embodiment, a commercially available rheometer viscosity measuring device is used as the rheometer viscosity measuring device. Meter, soliquid meter (MR-300 type), model name: HAAKE MARS III manufactured by Thermo Fisher Scientific, etc., but not limited to these.

[(A) epoxy resin]
The (A) epoxy resin used in the present embodiment is not particularly limited as long as it has two or more epoxy groups in one molecule and is generally used for semiconductor encapsulation.
(A) Epoxy resins include, for example, novolak type epoxy resins, cresol novolak type epoxy resins, naphthol novolac type epoxy resins, phenol aralkyl type epoxy resins, phenolbenzylaldehyde type epoxy resins, biphenyl type epoxy resins, and bisphenol A type epoxy resins. , bisphenol F type epoxy resins, dicyclopentadiene type epoxy resins, alicyclic epoxy compounds, and the like. Among them, biphenyl-type epoxy resins are preferable from the viewpoint of fluidity and reflow resistance.
(A) Epoxy resins may be used alone or in combination of two or more.

(A) The epoxy equivalent of the epoxy resin is preferably in the range of 50 to 500, more preferably in the range of 80 to 300, from the viewpoint of curability.

(A) The softening point of the epoxy resin is preferably 120° C. or lower, more preferably 110° C. or lower. (A) When the softening point of the epoxy resin is 120° C. or lower, the maximum flow stress of the encapsulating resin composition can be reduced. The lower limit of the softening point of the epoxy resin (A) is preferably 40°C, more preferably 50°C, from the viewpoint of improving the melt viscosity of the encapsulating resin composition.
In addition, the softening point in this specification refers to the "ring and ball softening point", and refers to a value measured according to ASTM D36.

(A) The content of the epoxy resin is preferably 3 to 10% by mass, more preferably 5 to 10% by mass, based on the total amount of the encapsulating resin composition. (A) When the content of the epoxy resin is 3% by mass or more, the heat resistance can be improved, and when it is 10% by mass or less, the warpage can be reduced.

[(B) Phenolic resin]
The (B) phenolic resin used in the present embodiment is a monomer, oligomer, or polymer having two or more phenolic hydroxyl groups in one molecule, and may be those generally used for semiconductor encapsulation. no.
(B) Phenolic resins include, for example, resorcinol, catechol, bisphenol A, bisphenol F, substituted or unsubstituted biphenol, and other phenolic compounds having two phenolic hydroxyl groups in one molecule; phenol, cresol, xylenol, Phenols such as resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol and/or naphthols such as α-naphthol, β-naphthol, dihydroxynaphthalene, formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, salicylaldehyde, etc. Novolak-type phenolic resin obtained by condensation or co-condensation of aldehydes in the presence of an acidic catalyst; Aralkyl-type phenolic resins such as resins, naphthol aralkyl resins and biphenylaralkyl resins; modified resins such as para-xylylene-modified phenolic resins, meta-xylylene-modified phenolic resins, melamine-modified phenolic resins and terpene-modified phenolic resins; dicyclopentadiene-type phenol resins, dicyclopentadiene-type naphthol resins; polycyclic aromatic ring-modified phenol resins; biphenyl-type phenol resins; Furthermore, it may be a phenol resin obtained by copolymerizing two or more of the above phenol resins. Among them, triphenylmethane-type phenol resins and aralkyl-type phenol resins are preferable.
(B) Phenol resin may be used alone or in combination of two or more.

(B) The softening point of the phenolic resin is preferably 120° C. or lower, more preferably 110° C. or lower. (B) When the softening point of the phenolic resin is 120° C. or lower, the maximum flow stress of the encapsulating resin composition can be reduced. The lower limit of the softening point of the (B) phenol resin is preferably 50°C, more preferably 60°C, from the viewpoint of workability.

(B) The content of the phenol resin is preferably 1 to 10% by mass, more preferably 2 to 8% by mass, based on the total amount of the encapsulating resin composition. When the content of the (B) phenol resin is 1% by mass or more, the heat resistance can be improved, and when it is 10% by mass or less, the fluidity can be improved.

[(C) Curing accelerator]
The (C) curing accelerator used in the present embodiment is not particularly limited as long as it is generally used as a curing accelerator for epoxy resins.
(C) Curing accelerators include, for example, 1,8-diazabicyclo[5.4.0]undecene-7,1,5-diazabicyclo[4.3.0]nonene-5,5,6-dibutylamino- Cycloamidine compounds such as 1,8-diazabicyclo[5.4.0]undecene-7; These cycloamidine compounds include maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2 quinone compounds such as ,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone and phenyl-1,4-benzoquinone; Compounds having intramolecular polarization obtained by adding a compound having a bond; tertiary amine compounds such as benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol and derivatives thereof; 2-methylimidazole , 2-ethylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl -4-methyl-5-hydroxymethylimidazole, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'- imidazoles such as undecylimidazolyl-(1′)]-ethyl-s-triazine, 2,4-diamino-6-[2′-ethyl-4′-methylimidazolyl-(1′)]-ethyl-s-triazine Imidazole compounds such as diamino-s-silicon-containing triazine compounds having a ring and derivatives thereof; organic phosphine compounds such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, tris(4-methylphenyl)phosphine, diphenylphosphine, and phenylphosphine maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5 to these organic phosphine compounds; Phosphorus compounds having intramolecular polarization obtained by adding quinone compounds such as methyl-1,4-benzoquinone and phenyl-1,4-benzoquinone, compounds having π bonds such as diazophenylmethane and phenolic resins; tetraphenylphosphonium Tetrasubstituted phosphonium/tetrasubstituted borate such as tetraphenylborate, tetraphenylphosphonium ethyltriphenylborate, tetrabutylphosphonium tetrabutylborate; 2-ethyl-4-methylimidazole/tetraphenylborate, N-methylmorpholine/tetraphenylborate, etc. and tetraphenylboron salts of and derivatives thereof.
(C) A hardening accelerator may use 1 type, and may mix and use 2 or more types.

Among them, the curing accelerator (C) is preferably an imidazole-based curing accelerator, and the use of the imidazole compound described above can improve the fluidity of the encapsulating resin composition.

(C) The content of the curing accelerator is preferably 0.01 to 0.1% by mass, more preferably 0.02 to 0.08% by mass, based on the total amount of the encapsulating resin composition. When the content of the curing accelerator (C) is 0.01% by mass or more, the curability can be improved, and when it is 0.1% by mass or less, the storage stability can be improved.

[(D) Silica]
(D) silica used in the present embodiment has a particle size distribution in which the ratio of particles with a particle size of 1.5 μm or less is 46% by volume or less. If the proportion of particles with a particle size of 1.5 μm or less exceeds 46% by volume, the rate of change in flow stress with respect to shear rate increases, and there is a risk that the wire will deform during sealing of the semiconductor element. From this point of view, the proportion of particles with a particle size of 1.5 μm or less is preferably 40% by volume or less. The lower limit of the ratio of particles having a particle size of 1.5 μm or less is preferably 10% by volume, more preferably 15% by volume.

In particular, (D) silica has (d1) a proportion of particles with a particle size of 1.5 μm or less of 10 to 46 vol%, and (d2) a proportion of particles with a particle size of more than 1.5 μm and 5 μm or less of 5 to 30 vol%. , (d3) the proportion of particles with a particle size of more than 5 μm and 10 μm or less is 5 to 30% by volume, (d4) the proportion of particles with a particle size of more than 10 μm and 20 μm or less is 10 to 45% by volume, (d5) a particle size of 20 μm. It is preferable to have a particle size distribution in which the proportion of particles with a particle size of more than 50 μm or less is 0 to 30% by volume, and (d6) the proportion of particles with a particle size exceeding 50 μm is 0 to 20% by volume, and (d1) the particle size is 1.5 μm. 15 to 40% by volume of the following particles, (d2) 6 to 27% by volume of particles having a particle size of more than 1.5 μm and 5 μm or less, and (d3) a percentage of particles having a particle size of more than 5 μm and 10 μm or less 6 to 27% by volume, (d4) 13 to 42% by volume of particles having a particle size of more than 10 μm and 20 μm or less, (d5) 0 to 28% by volume of particles having a particle size of more than 20 μm to 50 μm or less, and ( d6) It is more preferable to have a particle size distribution in which the proportion of particles with a particle size greater than 50 μm is 0-19% by volume.

Furthermore, the ratio (x/y) of the ratio (x) of particles with a particle size of 10 μm or less and the ratio (y) of particles with a particle size of more than 10 μm is preferably 0.4 to 2.4, and 0 0.5 to 1.4 is more preferred.
The particle size distribution of the silica (D) can be made within the above range by appropriately adjusting the average particle size and content of the silica to be used.
The particle size distribution of silica (D) can be measured by a laser diffraction particle size distribution analyzer (eg, MC-3000, manufactured by Malvern), specifically by the method described in Examples. be able to.

Although the shape of silica (D) is not particularly limited, it is preferably spherical. In addition, the average particle size of (D) silica is preferably 0.1 to 30 μm, more preferably 0.2 to 25 μm, and still more preferably 0.3 to 20 μm, from the viewpoint of imparting fluidity. .
The average particle size of the silica (D) can be obtained by calculating the 50% average particle size (D50) by laser diffraction using a laser diffraction/scattering particle size distribution analyzer or the like.

(D) The specific surface area of silica is preferably 2.0 to 5.25 m ² /g, more preferably 3.0 to 5.0 m ² /g. (D) When the specific surface area of silica is 2.0 m ² /g or more, burr generation can be reduced, and when it is 5.25 m ² /g or less, fluidity can be improved.
The specific surface area of the silica (D) can be measured by a BET one-point method based on nitrogen adsorption using a specific surface area measuring device.

(D) The content of silica is preferably 75 to 95% by mass, more preferably 80 to 90% by mass, based on the total amount of the encapsulating resin composition. When the content of (D) silica is 75% by mass or more, there is little dimensional change and warping can be reduced, and when it is 95% by mass or less, fluidity can be improved.

In addition to the above components, the encapsulating resin composition of the present embodiment contains a flame retardant, carbon black, an organic dye, an oxidation A coloring agent such as titanium or red iron oxide, a release agent, a coupling agent, and the like may be blended as necessary.

In the sealing resin composition of the present embodiment, the contents of (A) epoxy resin, (B) phenol resin, (C) curing accelerator, and (D) silica are preferably 80 to 100% by mass. , more preferably 85 to 99.8% by mass, more preferably 90 to 99.8% by mass.

The lowest melt viscosity of the encapsulating resin composition of the present embodiment is preferably 18 Pa·s or less, more preferably 16 Pa·s or less, and still more preferably 15 Pa·s or less.
The minimum melt viscosity can be measured by the method described in Examples.

<Semiconductor device>
The semiconductor device of the present embodiment comprises a substrate, a semiconductor element mounted on the substrate, and a cured product of the semiconductor encapsulating resin composition for encapsulating the semiconductor element. Further, the semiconductor device includes wiring formed on the surface of the semiconductor element and external connection terminals formed on the substrate.
Examples of substrates include wiring substrates such as interposers, lead frames, flexible printed substrates, and the like.
Semiconductor elements include transistors, integrated circuits, diodes, thyristors, and the like.

<Method for manufacturing a semiconductor device>
In the method for manufacturing a semiconductor device of the present embodiment, the semiconductor element mounted on the substrate is sealed using the resin composition for semiconductor sealing described above.
Examples of the method for encapsulating the semiconductor element mounted on the substrate include, when the encapsulating resin composition is used as a tablet, a molding method such as transfer molding or compression molding. When the resin composition is used as powder, for example, a molding method using compression molding can be used.

The molding temperature is preferably set to 150-250°C, more preferably 160-220°C, still more preferably 175-200°C. Also, the molding time is preferably set to 30 to 600 seconds, more preferably 45 to 240 seconds, and even more preferably 60 to 180 seconds. The transfer pressure is preferably set to 2 MPa or higher, more preferably 4 MPa or higher, and even more preferably 4 to 6 MPa.

The heating temperature for PMC (post-mold curing) after molding the sealing resin composition is not particularly limited. . The heating time for PMC (post-mold cure) after molding is not particularly limited, but is preferably 0.5 to 10 hours, more preferably 1 to 5 hours. By setting the conditions for PMC (post-mold cure) after molding the sealing resin composition within the above range, the sealing resin composition can be cured more reliably.

EXAMPLES Next, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.

(Examples 1 to 9 and Comparative Examples 1 and 2)
The types and blending amounts of the respective components shown in Table 2 were kneaded using a twin-screw extruder kneader under the conditions of a kneading temperature of 100° C. and a kneading time of 5 minutes to prepare a sealing resin composition.
In addition, in Table 2, a blank represents no compounding.

The details of each component shown in Table 2 used in the preparation of the encapsulating resin composition are as follows.

[(A) epoxy resin]
・ YX-4000HK: Biphenyl type epoxy resin (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: 180, softening point: 107 ° C.)

[(B) Phenolic resin]
・ MEH-7500: Triphenylmethane type phenol resin (trade name, manufactured by Meiwa Kasei Co., Ltd., hydroxyl equivalent: 95, softening point: 110 ° C.)
・ SN-485: Aralkyl-type phenol resin (trade name, manufactured by Nippon Steel Chemical & Materials Co., Ltd., hydroxyl equivalent: 205, softening point: 85 ° C.)

[(C) Curing accelerator]
・ 2P4MHZ: imidazole compound (trade name, manufactured by Shikoku Kasei Co., Ltd.)

[(D) Silica]
As (D) silica, spherical silica (D1) to (D9) having a particle size distribution shown in Table 1 was prepared by mixing each silica shown in Table 1 in the amount shown in Table 1.

[(D) Silica other than silica]
(D) As silica other than silica, spherical silica (X1) and (X2) having a particle size distribution shown in Table 1 is prepared by mixing each silica shown in Table 1 in the amount shown in Table 1. bottom.

The details of the silica used in the preparation of the spherical silicas (D1) to (D9) and the spherical silicas (X1) and (X2) are as follows.
・FB-875FC (trade name, manufactured by Denka Co., Ltd., average particle diameter 24 μm, specific surface area 4.5 m ² /g)
・MSR-7030 (trade name, manufactured by Tatsumori Co., Ltd., average particle diameter 19 μm, specific surface area 2.0 m ² /g)
・MSR-SF632 (trade name, manufactured by Tatsumori Co., Ltd., average particle diameter 15 μm, specific surface area 2.8 m ² /g)
・SS-0090 (trade name, manufactured by Sibelco, average particle size 10 μm, specific surface area 1.2 m ² /g)
・FB-1MDX (trade name, manufactured by Denka Co., Ltd., average particle diameter 2.2 μm, specific surface area 11.0 m ² /g)
・SP-30 (trade name, Nippon Steel Chemical & Materials Co., Ltd., average particle diameter 1.8 μm, specific surface area 9.0 m ² /g)
・SC-2500SQ (trade name, manufactured by Admatechs Co., Ltd., average particle diameter 0.5 μm, specific surface area 5.5 m ² /g)

[Other ingredients]
・ Silane coupling agent: Y-9669 (trade name, manufactured by Momentive)
・ Coloring agent: MA-100RMJ (carbon black) (trade name, manufactured by Mitsubishi Chemical Corporation)

The properties of the encapsulating resin compositions prepared in Examples 1 to 9 and Comparative Examples 1 and 2 were measured and evaluated under the following measurement conditions. Table 2 shows the evaluation results.

[Evaluation item]
(1) (D) Particle Size Distribution of Silica Using a laser diffraction particle size distribution analyzer (MC-3000, manufactured by Malvern), the particle size distribution of silica was measured with the refractive index set to 1.457.

(2) Using a minimum melt viscosity enhancement type flow tester (manufactured by Shimadzu Corporation, CFT-500C), nozzle length 1.0 mm, nozzle diameter 0.5 mm, temperature 175 ° C., load pressure 10 kgf / cm ² (about The lowest melt viscosity of the encapsulating resin composition was measured under the condition of 0.98 MPa).

(3) Maximum flow stress A tablet with a diameter of 18 mm was produced using 0.7 g of the encapsulating resin composition. Using a rheometer (manufactured by Thermo Fisher Scientific, model name: HAAKE MARS III), rotation speed control measurement, measurement temperature 175 ° C., shear rate 0.01 s ^-1 to 100 s ^-1 , measurement time 10 seconds Sealing resin The flow stress of the composition was measured.
From the measurement results, the maximum value of the flow stress in the range of shear rates from 1 s ^-1 to 10 s ^-1 was read.

(4) Wire flow rate (wire deformation)
An FBGA package (50 mm x 50 mm x 0.54 mm, chip thickness 0.54 mm, chip thickness 0.54 mm) was fabricated using the encapsulating resin composition under conditions of a mold temperature of 175°C and a curing time of 2 minutes, followed by a mold temperature of 175°C and a curing time of 8 hours. 31 mm) was molded by the transfer molding method, the deformation of the wire was observed with an X-ray inspection device (manufactured by Shimadzu Corporation, SMX-1000 Plus), and the wire flow rate at the maximum deformed portion (the wire flow rate before sealing The ratio (%) of the maximum distance between the position and the position of the wire after sealing to the length of the wire was measured.

(5) Reflow resistance After molding an FBGA package (50 mm × 50 mm × 0.54 mm, chip thickness 0.31 mm) by a transfer molding method using a sealing resin composition, After post-curing at 175° C. for 8 hours, moisture absorption treatment was performed at 30° C. and relative humidity of 60% RH for 192 hours. After that, it is heated in an infrared reflow furnace at 260 ° C. After cooling, an ultrasonic flaw detector (manufactured by Hitachi Construction Machinery Fine Tech Co., Ltd., product name: FS300II) is used to inspect the interface between the cured resin and the frame, and the cured resin. The presence or absence of peeling at the interface between the object and the semiconductor chip was examined, and the number of peeling occurrences (NG number) was counted.

Examples 1-1 containing (D) silica having a particle size distribution in which the proportion of particles with a particle size of 1.5 μm or less is 46% by volume or less, and having a maximum flow stress of 700 Pa or less at a shear rate of 1 s ⁻¹ to 10 s ⁻¹ All of the encapsulating resin compositions of No. 9 have a low minimum melt viscosity of 15.5 Pa s or less and a low wire flow rate of 10% or less, which reduces wire deformation during encapsulation of semiconductor elements. know that it can be done.

Claims (4)

(A) an epoxy resin, (B) a phenolic resin, (C) a curing accelerator and (D) silica,
(D) silica contains (d1) 10 to 46% by volume of particles with a particle size of 1.5 μm or less, (d2) 5 to 30% by volume of particles with a particle size of more than 1.5 μm and 5 μm or less, (d3) 5 to 30% by volume of particles with a particle size of more than 5 μm and 10 μm or less, (d4) 10 to 45% by volume of particles with a particle size of more than 10 μm and 20 μm or less, (d5) a particle size of more than 20 μm It has a particle size distribution in which the proportion of particles with a diameter of 50 μm or less is 0 to 30% by volume, and (d6) the proportion of particles with a diameter of more than 50 μm is 0 to 20% by volume,
A resin composition for semiconductor encapsulation having a maximum flow stress of 700 Pa or less at a shear rate of 1 s ^-1 to 10 s ^-1 measured using a rheometer at a temperature of 175°C. 2. The resin composition for semiconductor encapsulation according to claim 1, wherein the softening point of the (A) epoxy resin and/or the softening point of the (B) phenol resin is 120[deg.] C. or lower. A method for manufacturing a semiconductor device, wherein a semiconductor element mounted on a substrate is sealed using the resin composition for semiconductor sealing according to claim 1 or 2 . A semiconductor device comprising a substrate, a semiconductor element mounted on the substrate, and a cured product of the resin composition for semiconductor encapsulation according to claim 1 or 2 , obtained by encapsulating the semiconductor element.