JPH10335389A - Semiconductor device and sheet-shaped sealing material used for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device having superior reliability, while improving the effect for relaxing stresses on a semiconductor element, a wiring circuit board and an electrode for connection. SOLUTION: For this device, a semiconductor element 4 is loaded through multiple electrode parts 2 and 3 for connection onto a wiring circuit board 1, and a void between the wiring circuit board 1 and the semiconductor element 4 is sealed by a sealing resin layer 5. Furthermore, the sealing resin layer 5 is equipped with an extension elasticity modulus of 300 to 150000 MPa at 25 deg.C as well as the setting substance characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device in which a semiconductor element is mounted on a wiring circuit board such as a motherboard or a daughter board in a face-down structure, and a sheet-like sealing material used for the semiconductor device.

[0002]

2. Description of the Related Art Recent demands for improvement in the performance of semiconductor devices include a method of mounting a semiconductor element in a face-down structure on a motherboard on which a wiring circuit is formed or on a wiring circuit board such as a daughter board (flip-chip type). , Direct chip attach method, etc.). This is a conventional method, for example,
A motherboard in the form of a package that takes contacts from a semiconductor element on a lead frame with gold wires,
Alternatively, in the method of mounting on a wiring circuit board such as a daughter board, there is a problem that information transmission delay by wiring, information transmission error due to crosstalk, and the like occur.

[0003]

On the other hand, in the flip chip method and the direct chip attach method,
Since the semiconductor elements having different linear expansion coefficients are directly electrically connected to the printed circuit board, the reliability of the connection portion is a problem. As a countermeasure, a liquid resin material is injected into the gap between the semiconductor element and the wiring circuit board and cured to form a cured resin, and the stress concentrated on the electrical connection portion is also dispersed in the cured resin. A method for improving connection reliability has been adopted. However, since the filling of the gap between the semiconductor element and the printed circuit board with the liquid resin material is performed by utilizing the capillary effect of the liquid resin material, the viscosity of the liquid resin material is set to a low value. There is a need to. Therefore, in order to obtain a low-viscosity material, the range of material selection is narrowed, and it has been difficult to use a rubber component having a high low-stress effect or a highly reliable phenol resin. As a result, it was difficult to perform resin sealing having a high stress relaxation effect, and it was difficult to obtain a highly reliable resin. Further, the liquid resin material needs to be stored at an extremely low temperature (−40 ° C.). In addition, the liquid resin material needs to be injected into a gap between the semiconductor element and the printed circuit board with a syringe. And it is difficult to control the injection amount.

The present invention has been made in view of such circumstances, and a semiconductor device having an excellent effect of alleviating the stress generated in the semiconductor element, the wiring circuit board, and the connection electrode and having high reliability, and It is an object of the present invention to provide a sheet-shaped sealing material in which a sealing resin layer can be easily formed in a gap with a printed circuit board.

[0005]

According to the present invention, a semiconductor device is mounted on a printed circuit board via a plurality of connecting electrodes, and the printed circuit board and the semiconductor element are connected to each other. The first gist is a semiconductor device in which a gap between them is sealed with a sealing resin layer, wherein the sealing resin layer has the following cured product characteristics (X). (X) The tensile modulus at 25 ° C. is 300 to 15000.
MPa.

A sheet-like sealing material used when forming a sealing resin layer of the semiconductor device, wherein the sheet-like sealing material has the following cured product characteristics (X). Is the second gist. (X) The tensile modulus at 25 ° C. is 300 to 15000.
MPa.

That is, according to the present invention, in a semiconductor device having a sealing resin layer formed in a gap between a printed circuit board and a semiconductor element connected through a plurality of connection electrode portions, When the cured product characteristic (X) of the resin layer itself is provided with the tensile elastic modulus in the above specific range, the reliability is improved, and in particular, the electrical connection between the semiconductor element and the wiring circuit board is stabilized under a thermal cycle. Device.

Further, the present inventors have found that, in the process of finding out the present invention, a biphenyl type epoxy resin and an acrylonitrile-butadiene copolymer are used as a material for forming the sealing resin layer having the above-mentioned specific cured product characteristic (X). When an epoxy resin composition containing a specific phenolic resin is used, a more excellent sealing resin layer having low moisture absorption and high adhesiveness is formed, and as a result, the vapor phase after moisture absorption is obtained. It has been found that more stable electrical connection can be provided to a stress test such as soldering (VPS).

As a material for forming the sealing resin layer, a sheet-like sealing material having the above-mentioned cured product characteristics (X),
In particular, a sheet-like sealing material made of the epoxy resin composition is preferably used.

[0010]

Next, embodiments of the present invention will be described in detail.

As shown in FIG. 1, the semiconductor device of the present invention has a face-down configuration in which a semiconductor element 4 is mounted on one surface of a printed circuit board 1 via a plurality of connection electrode portions 2 and connection electrode portions 3. Take the structure. Then, a sealing resin layer 5 is formed between the printed circuit board 1 and the semiconductor element 4.

In the present invention, the connection electrode portion may be a known electrode alone, but is a concept including an electrode and a conductor disposed on the electrode such as a joint ball or a joint bump. Therefore, in general, both the connection electrode portion of the printed circuit board and the connection electrode portion of the semiconductor element may be connected only by the electrode, but usually at least one of the electrode and the joint ball (or joint bump) is connected. ), The two electrode portions are connected to each other.

Therefore, in a normal mode, the plurality of connection electrodes 2 and 3 for electrically connecting the printed circuit board 1 and the semiconductor element 4 are provided with joint balls or the like on the surface of the printed circuit board 1 in advance. Or the semiconductor element 4
A joint ball or the like may be provided on the surface. Furthermore, joint balls or the like may be provided on both the surface of the printed circuit board 1 and the surface of the semiconductor element 4 in advance, and the electrode portions of both may be electrodes only.

The material of the plurality of connection electrode portions 2 and 3 is not particularly limited, but may be, for example, gold, silver,
Copper, aluminum, nickel, chromium, tin, lead, indium, solder and alloys thereof can be used. The shape of the connection electrode portion is not particularly limited, but a shape having a high effect of extruding the sealing resin between the electrode portions 2 and 3 of the printed circuit board 1 and the semiconductor element 4 is desirable. It is preferable that the surface of the electrode portion has few recesses.

The material of the printed circuit board 1 is not particularly limited, but is roughly classified into a ceramic substrate and a plastic substrate. Examples of the plastic substrate include an epoxy glass substrate, a bismaleimide triazine substrate, Examples include a polyphenylene ether substrate.

Next, the sealing resin layer 5 formed in the gap between the printed circuit board 1 and the semiconductor element 4 of the semiconductor device of the present invention will be described.

In the present invention, as the material for forming the sealing resin layer 5, a sheet-shaped sealing material having specific physical properties is used. For example, an epoxy resin composition is used as the molding material.

The above epoxy resin composition is obtained using a specific epoxy resin (component A) and an acrylonitrile-butadiene copolymer (component B).

The specific epoxy resin (component A) is a biphenyl type epoxy resin represented by the following general formula (1). The biphenyl type epoxy resin has a phenyl ring having a glycidyl group and An alkyl group having 1 to 4 carbon atoms represented by R _{1 to} R ₄ is added.
Therefore, the sheet-shaped sealing material obtained from the epoxy resin composition containing the biphenyl-type epoxy resin can exhibit water repellency and low moisture absorption in semiconductor device sealing applications.

[0020]

Embedded image

The alkyl group having 1 to 4 carbon atoms represented by R _{1 to} R ₄ in the general formula (1) includes a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, and a sec group. Examples thereof include a linear or branched lower alkyl group such as -butyl group and tert-butyl group, and particularly preferably a methyl group, and R _{1 to} R ₄ may be the same or different. Among them, it is particularly preferable to use a biphenyl type epoxy resin represented by the following formula (3) wherein all of R _{1 to} R ₄ are methyl groups.

[0022]

Embedded image

The biphenyl type epoxy resin represented by the general formula (1) has an epoxy equivalent of 177 to 240.
It is preferable to use those having a softening point of 80 to 130 ° C. in g / eq, and especially, an epoxy equivalent of 177 to 22.
It is particularly preferable to use those having 0 g / eq and a softening point of 80 to 120 ° C.

The proportion of the biphenyl epoxy resin (component A) in all the organic components of the epoxy resin composition which is the material for forming the sheet-shaped sealing material of the present invention is preferably 1
The range is preferably from 0 to 96% by weight (hereinafter abbreviated as "%"), and particularly preferably from 20 to 94%. That is, if the blending ratio of the biphenyl-type epoxy resin (component A) is less than 10%, water repellency and low hygroscopicity are hardly exhibited in the encapsulation of a semiconductor element.
%, The obtained sheet-shaped sealing material itself becomes brittle, and handling becomes difficult.

In the material for forming the sheet-like sealing material of the present invention, the biphenyl-type epoxy resin (component A) is
Other epoxy resins such as cresol novolak type epoxy resin, phenol novolak type epoxy resin and bisphenol A type epoxy resin may be used alone or in combination of two or more. When another epoxy resin is used in this manner, it is preferable to set the amount of the biphenyl-type epoxy resin (component A) to be 20% or more of the entire epoxy resin component. , 50% or more.

The epoxy resin composition may optionally contain a curing agent for the epoxy resin.
Examples of such a curing agent include, but are not particularly limited to, various commonly used curing agents, for example, phenol resins, acid anhydrides such as methylhexahydrophthalic anhydride, and amine compounds. From the viewpoint, a phenol resin is particularly preferably used. Among them, it is more preferable to use a novolak type phenol resin from the viewpoint of adhesiveness and the like. From the viewpoints of better adhesive strength and hygroscopicity, it is particularly preferable to use a phenol resin represented by the following general formula (2).

[0027]

Embedded image

The number of repetitions m in the general formula (2) is 0
Or a positive integer, m is particularly preferably an integer of 0 to 10, and more preferably, m is an integer of 0 to 8;

The phenolic resin represented by the general formula (2) is, for example, an aralkyl ether and phenol,
It is obtained by reacting with a Friedel Crafts catalyst.

Particularly, the phenol resin has a hydroxyl equivalent of 147 to 250 g / eq and a softening point of 60 to 12 g / eq.
The thing of 0 degreeC is preferable, and especially, a hydroxyl equivalent is 147.
Those having a softening point of from 60 to 110 ° C. are suitable.

The mixing ratio of the phenol resin (component C) to the biphenyl type epoxy resin (component A) is such that the hydroxyl group in the phenol resin (component C) per equivalent of epoxy group in the biphenyl type epoxy resin (component A). Is preferably 0.7 to 1.3 equivalents, and more preferably 0.9 to 1.1 equivalents.

The epoxy resin composition which is the material for forming the sheet-shaped sealing material of the present invention may further contain a curing accelerator in addition to the epoxy resin curing agent. As such a curing accelerator, various curing accelerators conventionally known as epoxy resin curing accelerators can be used, for example, amine-based, phosphorus-based, boron-based, phosphorus-boron-based and the like. Curing accelerators. Above all,
Triphenylphosphine, diazabicycloundecene and the like are preferred. These may be used alone or in combination of two or more.

The above biphenyl type epoxy resin (component A)
The acrylonitrile-butadiene copolymer (component B) used together with the acrylonitrile copolymer (NBR) is not only when the content of the acrylonitrile copolymer (NBR) is 100%,
It refers to a copolymer in a broad sense including the case where another copolymer component is contained in this NBR. As other copolymerization components, for example, hydrogenated acrylonitrile-butadiene rubber,
Acrylic acid, acrylic acid ester, styrene, methacrylic acid and the like can be mentioned, and among them, acrylic acid and methacrylic acid are preferable from the viewpoint of excellent adhesion to metals and plastics. That is, acrylonitrile-butadiene-methacrylic acid copolymer and acrylonitrile-butadiene-acrylic acid copolymer are preferably used. Further, the amount of acrylonitrile bonded in the NBR is,
It is preferably from 10 to 50%, and particularly preferably from 15 to 40%.

The proportion of the acrylonitrile-butadiene-based copolymer (component B) in all the organic components of the epoxy resin composition which is the material for forming the sheet-shaped sealing material of the present invention is particularly in the range of 2 to 60%. Is preferred, especially 3
A range of ５０50% is preferred. That is, if the blending ratio of the acrylonitrile-butadiene-based copolymer (component B) is less than 2%, in a semiconductor device sealing application,
It is difficult to exhibit excellent durability in each stress test under high-temperature and high-humidity conditions under cooling and heating cycles.
If it exceeds 60%, there is a tendency that the fixing force at high temperatures tends to decrease.

The epoxy resin composition, which is a material for forming the sheet-shaped sealing material of the present invention, may optionally contain other materials (organic materials and inorganic materials) together with the above-mentioned component A, curing agent and component B. It can also be blended. Examples of the organic material include a silane coupling agent, a titanium coupling agent, a surface conditioner, and an antioxidant. Examples of the inorganic material include alumina, silica, various inorganic fillers such as silicon nitride, copper, silver, and the like. Examples include metal particles such as aluminum, nickel, and solder, as well as pigments and dyes. The blending ratio of the inorganic material is not particularly limited, but is preferably set to 85% or less, more preferably 80% or less in the entire blend (the entire epoxy resin composition).
That is, if the amount is more than the above-mentioned compounding ratio, the electrical connection between the electrode of the semiconductor element and the electrode of the printed circuit board is not performed well, and the problem is likely to occur.

The sheet-shaped sealing material of the present invention can be produced, for example, as follows. First, the above biphenyl type epoxy resin (component A), acrylonitrile-
A predetermined amount of each component of the butadiene copolymer (component (B)) is blended, and if necessary, various components such as a curing agent, a curing accelerator, and various fillers are blended in a predetermined amount. Prepare. Then, the epoxy resin composition is mixed and dissolved in a solvent such as toluene, methyl ethyl ketone, or ethyl acetate, and the mixed solution is applied on a base film such as a polyester film subjected to a release treatment. Next,
By drying the applied base film at 50 to 160 ° C. and removing a solvent such as toluene, a target sheet-like sealing material can be produced on the base film. Further, as another method, the target sheet-like sealing material can be produced by heat-melting extrusion without using a solvent such as toluene. Such a sealing material is generally devised so that a thixotropy-imparting agent such as a rubber component is mixed in the sealing material to suppress the fluidity during heating during heat curing. is there.

The sheet-like sealing material thus obtained preferably has the following properties, that is, a property that the gel time is 175 ° C. and 10 to 120 seconds. The gel time is a value measured on a hot plate at 175 ° C.

The cured product obtained by curing the sheet-like sealing material of the present invention thus obtained can be produced, for example, as follows. That is, by heating and curing the sheet-shaped sealing material obtained by the above method at 100 to 225 ° C, preferably 120 to 200 ° C, for 3 to 300 minutes, preferably for 5 to 180 minutes, the desired cured product is obtained. Can be manufactured. Note that the above curing conditions are the same as the heat curing conditions at the time of forming the sealing resin layer in the semiconductor device manufacturing method described later.

The obtained cured product must have the following cured product characteristics (X). (X) The tensile modulus at 25 ° C. is 300 to 15000.
MPa.

More preferably, the tensile modulus at 25 ° C. is 500 to 12,000 MPa, particularly preferably 1000
〜１０10000 MPa. By setting such a range, the stress applied to the semiconductor element, the printed circuit board, and the connection electrode portion can be alleviated in a well-balanced manner under a thermal cycle. That is, when the tensile elastic modulus at 25 ° C. is less than 300 MPa, cracks are easily generated in the connection electrode portion, and the tensile elastic modulus at 25 ° C. is 15 MPa.
If the pressure exceeds 000 MPa, cracks are likely to occur in the semiconductor element.

The tensile modulus at 25 ° C. is
A value measured according to JIS K 6900,
Specifically, it is measured by a universal tensile tester (Autograph, manufactured by Shimadzu Corporation).

As described above, in the semiconductor device of the present invention, a semiconductor element is mounted on a printed circuit board via a plurality of connection electrodes, and a gap is provided between the printed circuit board and the semiconductor element. Has a face-down structure sealed by a sealing resin layer. An example of a method for manufacturing such a semiconductor device will be described below, but the method is not limited to this.

First, as shown in FIG. 2, a solid sheet-like sealing material 10 is placed on a printed circuit board 1 provided with a plurality of spherical connection electrodes 2 via the connection electrodes 2. Place. Next, as shown in FIG. 3, the semiconductor element 4 provided with the connection electrode portion 3 is arranged at a predetermined position on the sheet-shaped sealing material 10 and heated and pressed to thereby form the two connection electrodes. The electrical connection between the parts 2 and 3 and the curing of the sheet-shaped sealing material 10 are performed, and the electrical connection and fixation between the printed circuit board 1 and the semiconductor element 4 are completed.

The size of the sheet-shaped sealing material 10 is appropriately set according to the size (area) of the semiconductor element 4 to be mounted, and is generally the same as the size (area) of the semiconductor element 4. It is preferable to set.

The thickness of the sheet-shaped sealing material 10 is not particularly limited, but fills the gap between the semiconductor element 4 and the printed circuit board 1 and sets the gap between the connection electrode portions 2 and 3. Can be appropriately set so as not to hinder the electrical connection, and is usually 5 to 200 μm, preferably 10 to 200 μm.
It is set to 120 μm.

In the method of manufacturing a semiconductor device, the heating temperature at which the sheet-like sealing material 10 is heated and melted to be in a molten state may be selected from the heat resistance of the semiconductor element 4 and the wiring circuit board 1 and the connection temperature. Melting points of the electrode parts 2 and 3,
Further, it is appropriately set in consideration of the softening point, heat resistance, and the like of the sheet-shaped sealing material 10. Examples of the heating method include an infrared reflow oven, a dryer, a hot air blower, and a hot plate.

Further, when filling the gap between the semiconductor element 4 and the printed circuit board 1 with the sealing material in the molten state, it is preferable to apply pressure as described above. The conditions are appropriately set depending on the material and number of the connection electrode portions 2 and 3 and the temperature, but are specifically set in the range of 0.01 to 0.5 kgf / piece, preferably 0.1 to 0.5 kgf / piece. It is set in the range of 02 to 0.3 kgf / piece.

In the semiconductor device manufactured as described above, the size of the semiconductor element 4 is usually set to the width 2
２０20 mm × length 2-30 mm × thickness 0.1-2 mm. The size of the printed circuit board 1 on which the printed circuit on which the semiconductor element 4 is mounted is formed usually has a width of 10 to 10.
70 mm x length 10 to 70 mm x thickness 0.05 to 3.0
mm. The distance between the semiconductor element 4 and the gap between the wiring circuit board 1 in which the molten sealing resin is filled is usually 5 to 200 μm.

As described above, the sealing resin layer 5 formed by sealing using the sheet-like sealing material must have the following cured product characteristics (X). More preferably, the tensile modulus at 25 ° C. is 500
１12000 MPa, particularly preferably 1000 to 100
00 MPa. (X) The tensile modulus at 25 ° C. is 300 to 15000.
MPa.

Further, in addition to the properties of the cured product, the sealing resin layer 5 preferably has a water absorption of 1.5% or less. More preferably, the water absorption is 1.2% or less. Further, the ionic impurities contained in the sealing resin layer 5 ^{(e.g., Na +, K +, NH} 3 +, Cl -, S
O ₄ ^2- ) is preferably at most 50 ppm each. The measurement of the water absorption was performed by leaving the cured product at 85 ° C. × 85% RH for 168 hours and then using a trace moisture meter (Hiranuma Moisture Analyzer AQ-5, manufactured by Hiranuma Sangyo Co., Ltd.). In addition, the measurement of the ionic impurities was performed by crushing a cured product, extracting the cured product with pure water at 121 ° C. for 24 hours, and measuring the content by ion chromatography.

In the semiconductor device of the present invention, the semiconductor element and the two electrode portions of the printed circuit board are brought into contact with each other via the sheet-like sealing material, and the sheet is heated and preferably cured by heating and pressing. This is as described above.

The above-mentioned pressurization preferably hardens the sealing resin while flattening or flattening the connection electrode portion such as solder.

At this time, generally, the material constituting the connection electrode portion is formed of a material which can flow when heated, for example, solder. After the sheet-like sealing material as the sealing resin is cured, the adhesive between the semiconductor element and the wiring circuit board is heated to about 215 ° C. in order to preferably melt the solder constituting the connection electrode portion. Thus, the semiconductor device of the present invention is generally used. After the sheet-shaped sealing material is cured, the step of melting the material such as the solder constituting the connection electrode portion in this way is not described in the above-described manufacturing method, but is usually performed in the present application.

In the sealing using the sheet-shaped sealing material according to the present invention, the following can be said in most cases.

That is, when solder is used as the connection electrode portion, the melting and bonding of both the semiconductor element electrode portion and the wiring circuit board electrode portion (land portion) can be suitably performed without flux. It is common to be done.

Although the reason for the above is not clear, at the stage when the joined body of the semiconductor element and the printed circuit board is obtained, the periphery of the solder serving as the connection electrode portion is almost always covered with the cured resin, Is in a state of being cut off,
Also, it is considered that cracks are generated on the solder surface during the above-mentioned flattening due to the pressure of the electrode portion, and the ground surface (non-oxidized surface) of the solder is exposed. Further, in the case of using a sheet-like sealing material containing at least one of a trace amount of a chlorine component and an organic acid component, for example, a sheet made of an epoxy resin composition, at least one of the chlorine component and the organic acid component is used. It is effective in removing an oxide film formed on the surface of the connection electrode portion made of solder, and it is considered that this oxide film is removed. Then, in such an environment, by heating to about 215 ° C., both the electrode portions of the semiconductor device electrode portion and the wiring circuit board electrode portion are melted.

Next, examples will be described together with comparative examples.

First, prior to the examples, the following components were prepared.

[Epoxy resin a1] Biphenyl type epoxy resin represented by the following structural formula

[0060]

Embedded image

[Epoxy resin a2] Cresol novolak type epoxy resin (epoxy equivalent: 195 g / eq, melting point: 80 ° C.)

[Acrylonitrile-butadiene copolymer b1] Acrylonitrile-butadiene-methacrylic acid copolymer [Mooney viscosity: 50, bound acrylonitrile content: 30%, bound carboxyl group amount: 0.05 eph
r (moles per 100 g of rubber)]

[Acrylonitrile-butadiene copolymer b2] Acrylonitrile-butadiene-acrylic acid copolymer (Mooney viscosity: 80, bound acrylonitrile content: 20%, bound carboxyl group content: 0.02 eph)
r)

[Curing agent c1] A phenol resin represented by the following structural formula (hydroxyl equivalent: 175 g / eq, softening point 7
5 ℃)

[0065]

Embedded image

[Hardening agent c2] Phenol novolak resin (hydroxyl equivalent: 105 g / eq, softening point 60 ° C.)

[Curing accelerator] Triphenylphosphine

[Inorganic Filler] Spherical silica (average particle size:
3 μm, maximum particle size: 30 μm)

[0069]

Examples 1 to 10 and Comparative Examples 1 to 7 The components shown in Tables 1 to 3 below were blended in the proportions shown in the table to prepare epoxy resin compositions. The epoxy resin composition was mixed and dissolved in toluene, and the mixed solution was applied on a polyester film subjected to a release treatment. Next, the polyester film to which the mixed solution was applied was dried at 120 ° C., and toluene was removed to prepare a desired sheet-shaped sealing material having a thickness of 100 μm on the polyester film.

[0070]

[Table 1]

[0071]

[Table 2]

[0072]

[Table 3]

Using the thus obtained sheet-like sealing materials of Examples and Comparative Examples, semiconductor devices were manufactured in accordance with the above-described semiconductor device manufacturing method. That is, as shown in FIG. 2, the connection electrode portion 2 (material: solder, melting point: 183)
After placing the sheet-shaped sealing material 10 on a printed circuit board 1 (glass epoxy board having a thickness of 1 mm) provided with a temperature and a shape: a cylindrical shape having a diameter of 150 μm and a height of 30 μm), as shown in FIG. As described above, the connection electrode portion 3 (material: solder, melting point: 2) is provided at a predetermined position on the sheet-like sealing material 10.
99 ° C, shape: spherical shape with a diameter of 120 µm x a height of 90 µm)
Was mounted (thickness: 350 μm, size: 13 mm × 9 mm). Thereafter, the sheet-shaped sealing material is heated and melted under the conditions of a heating temperature of 150 ° C., a load of 0.1 kgf, the number of electrodes, and 1 minute, and the resin in the molten state is filled in the gap between the wiring circuit board 1 and the semiconductor element 4 Then, the connection electrodes 2 and 3 were electrically connected. Thereafter, the above resin is thermally cured (condition: 150 ° C. × 6).
0 minutes) and melt the connection electrode portion 2 (condition: 250 ° C. ×
30 seconds), the semiconductor device in which the voids were sealed with the sealing resin layer 5 as shown in FIG.
Each was produced.

An initial energization test was performed on the obtained semiconductor device, and a thermal shock test [TST test (condition:-
After performing 500 cycles (55 ° C. × 5 minutes⇔125 ° C. × 5 minutes) (4 pieces in each example), an energization test and an inspection for the presence or absence of cracks in the semiconductor element were performed, and the results are shown in Tables 4 to 6 below. Indicated.

Further, the four samples in each of the examples which were not subjected to the above TST test were subjected to moisture absorption for 168 hours in an environment of 30 ° C. × 60% RH, and then subjected to VPS (vapor phase sold).
ering) (215 ° C. × 90 seconds), and then an electricity test was performed. The results are shown in Tables 4 to 6 below.

On the other hand, only the sheet-like sealing material obtained in each of the above Examples and Comparative Examples was heated at 150 ° C. for 60 minutes to obtain a sheet-like cured product. The tensile modulus at 25 ° C. of each cured sheet was measured using a universal tensile tester (Autograph, manufactured by Shimadzu Corporation). These results are shown in Tables 4 to 6 below.

[0077]

[Table 4]

[0078]

[Table 5]

[0079]

[Table 6]

As a result of the above Tables 4 to 6, with respect to the products of the Examples, the initial energization check, the energization test after the TST test, the cracked state of the semiconductor chip after the TST test, the moisture absorption V
It was confirmed that no defect occurred in all of the current tests after the PS. On the other hand, in any of the above-mentioned tests, it was confirmed that the comparative example product was defective. From this, the product of the example is different from the product of the comparative example in initial energization, TST test,
It is clear that stable energization is ensured for stress tests such as.

[0081]

As described above, the present invention provides a semiconductor device in which a sealing resin layer is formed in a gap between a printed circuit board and a semiconductor element, which is connected via a plurality of connection electrode portions. , A sealing resin layer having a cured product characteristic (X) having a tensile modulus in the specific range is formed. For this reason, stress generated in the wiring circuit board, the semiconductor element, and the connection electrode portion is relaxed, and a highly reliable connection is obtained. In particular, the electrical connection between the semiconductor element and the wiring circuit board is stable under a cooling / heating cycle. Become

As a material for forming the sealing resin layer having the above-mentioned specific cured product characteristics (X), a biphenyl type epoxy resin and an acrylonitrile-butadiene copolymer are contained, and in some cases, a specific phenol resin is further contained. When an epoxy resin composition using is used, a more excellent sealing resin layer is formed in low hygroscopicity and high adhesiveness, and as a result,
A more stable electrical connection is provided to a stress test such as vapor phase soldering (VPS) after moisture absorption.

As the material for forming the sealing resin layer, a sheet-like sealing material having the above-mentioned cured product characteristics (X), particularly a sheet-like sealing material comprising the above-mentioned epoxy resin composition, is used. It is preferably used because it facilitates resin encapsulation and significantly improves the manufacturing efficiency of the semiconductor device.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of a semiconductor device of the present invention.

FIG. 2 is an explanatory sectional view illustrating a manufacturing process of the semiconductor device.

FIG. 3 is an explanatory sectional view illustrating a manufacturing process of the semiconductor device;

[Description of Signs] 1 printed circuit board 2 connection electrode section 3 connection electrode section 4 semiconductor element 5 sealing resin layer 10 sheet-shaped sealing material

 ──────────────────────────────────────────────────の Continuing on the front page (72) Koji Noro, Inventor 1-1-2 Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation

Claims (10)

[Claims] 1. A semiconductor in which a semiconductor element is mounted on a printed circuit board via a plurality of connection electrodes, and a gap between the printed circuit board and the semiconductor element is sealed by a sealing resin layer. A semiconductor device, wherein the sealing resin layer has the following cured product characteristics (X). (X) The tensile modulus at 25 ° C. is 300 to 15000.
MPa. 2. The semiconductor device according to claim 1, wherein the sealing resin layer is formed of an epoxy resin composition containing the following components (A) and (B). (A) A biphenyl type epoxy resin represented by the following general formula (1). Embedded image (B) Acrylonitrile-butadiene copolymer. 3. The semiconductor device according to claim 2, wherein the acrylonitrile-butadiene-based copolymer as the component (B) is an acrylonitrile-butadiene-methacrylic acid copolymer. 4. The semiconductor device according to claim 2, wherein the acrylonitrile-butadiene-based copolymer as the component (B) is an acrylonitrile-butadiene-acrylic acid copolymer. 5. The epoxy resin composition according to claim 2, wherein the epoxy resin composition is an epoxy resin composition containing the following component (C) together with the components (A) and (B). Semiconductor device. (C) A phenol resin represented by the following general formula (2). Embedded image 6. A sheet-like sealing material used for forming a sealing resin layer of the semiconductor device according to claim 1, wherein the sheet-like sealing material is as follows: A sheet-shaped sealing material, characterized by having the following cured product properties (X). (X) The tensile modulus at 25 ° C. is 300 to 15000.
MPa. 7. The sheet-shaped sealing material according to the following (A):
The sheet-like sealing material according to claim 6, wherein the sheet-like sealing material is formed in a sheet shape using an epoxy resin composition containing (B) and (B). (A) A biphenyl type epoxy resin represented by the following general formula (1). Embedded image (B) Acrylonitrile-butadiene copolymer. 8. The sheet-like sealing material according to claim 7, wherein the acrylonitrile-butadiene copolymer as the component (B) is an acrylonitrile-butadiene-methacrylic acid copolymer. 9. The sheet-like sealing material according to claim 7, wherein the acrylonitrile-butadiene-based copolymer as the component (B) is an acrylonitrile-butadiene-acrylic acid copolymer. 10. The epoxy resin composition according to claim 7, wherein the epoxy resin composition comprises the following component (C) together with the components (A) and (B). Sheet-shaped sealing material. (C) A phenol resin represented by the following general formula (2). Embedded image