JPH0964103A - Semiconductor device mounting body, mounting method therefor, and sealing material for mounting the same - Google Patents

Abstract

(57) Abstract: To improve the fluidity of an encapsulant used for flip-chip mounting using a conductive adhesive, and to realize a semiconductor device mounting body with high reliability and productivity. A semiconductor device (1) having an electrode pad (2),
A substrate 6 having a terminal electrode 5, a bump electrode 3 provided on a part of the electrode pad 2, and a flexible conductive adhesive layer 4
And a sealing layer 7 formed by curing a composition having a viscosity of 100 Pa · s or less and a thixotropic index of 1.1 or less
And a semiconductor device mounting body is realized. The composition includes, for example, a resin binder containing a polyepoxide, an acid anhydride, and a rheology modifier as a main component, and a filler, and a free acid in the acid anhydride as a rheology modifier and a polar group on the surface of the filler. A substance having a function of inhibiting the interaction with is used. By improving the fluidity of the sealing material, a sealing layer that quickly fills a narrow gap without generating bubbles is formed, and thus reliability and productivity are improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mounts a semiconductor device on a substrate by a flip chip mounting method via a conductive adhesive, and mechanically connects the substrate and the semiconductor device via a resin sealing layer. And a mounting method of the semiconductor device.

[0002]

2. Description of the Related Art Conventionally, soldering has been generally used for connecting a connection terminal of an electronic component such as a semiconductor device and a terminal electrode of a circuit pattern on a substrate. However, recently, in addition to the downsizing of semiconductor packages and the like, the number of connection terminals has increased and the space between the connection terminals has become narrower. For this reason, conventional soldering, in which the area of the bonded portion is large, cannot be dealt with.

Therefore, recently, attempts are being made to improve the mounting area by directly mounting (flip chip mounting) the terminal electrodes on the substrate with the active element surface of the chip facing downward. Although many proposals have been made and implemented for this flip chip mounting method, typical examples will be introduced below.

(1) Bonding of low melting point metal such as solder As shown in FIG. 8, a solder bump electrode 8 is provided on an electrode pad 2 of a semiconductor device 1, and a terminal electrode 5 on a substrate 6 is provided.
After aligning with and melting the solder, semiconductor device 1
And the substrate 6 are electrically connected. As a method similar to this, as shown in FIG. 9, a gold bump electrode 3 is formed, and a low melting point metal plating layer, for example, an indium plating layer 9 is formed between the bump electrode 3 and the terminal electrode 5 on the substrate 6. A method has also been proposed in which the low melting point metal of the indium plated layer 9 is formed and electrically connected to the semiconductor device 1 and the substrate 6 is mechanically joined via the sealing layer 10. .

(2) Bonding by Curing Shrinkage Stress of Sealing Resin As shown in FIG.
After the gold bump electrode 3 is provided on the substrate, and the bump electrode 3 on the semiconductor device 1 and the terminal electrode 5 on the substrate 6 are aligned with each other, after filling the gap between the semiconductor device 1 and the substrate 6 with a sealing material. The encapsulating material is cured to form the encapsulating layer 12, and the curing and shrinking force of the encapsulating layer 12 causes the bump electrode 3 and the terminal electrode 5
A compressive stress is generated between the two to electrically connect the two, and at the same time, the semiconductor device 1 and the substrate 6 are mechanically joined. In order to improve the connection reliability, the gold plating layer 11 may be formed on the terminal electrode 5 as shown in FIG.

(3) Bonding with Anisotropic Conductive Adhesive As shown in FIG.
The bump electrode 3 made of gold is provided on the substrate, and the gap between the semiconductor device 1 and the substrate 6 is filled with an anisotropic conductive adhesive in which conductive particles are dispersed in a binder, and heated under pressure. Anisotropic conductive adhesive layer 1 by curing anisotropic conductive adhesive
By forming 3, the bump electrode 3 and the terminal electrode 5 on the substrate 6 are electrically connected, and at the same time, the semiconductor device 1 and the substrate 6 are mechanically joined.

(4) Bonding by Conductive Adhesive As shown in FIG. 12, the electrode pad 2 of the semiconductor device 1
By providing the bump electrode 3 made of gold on the substrate, transferring the conductive adhesive to the bump electrode 3, aligning the bump electrode 3 with the terminal electrode 5 on the substrate 6, and then curing the conductive adhesive. , The bump electrode 3 and the terminal electrode 5 are electrically connected via the conductive adhesive layer 4. After that, the gap between the semiconductor device 1 and the substrate 6 is filled with a sealing material, which is cured to form the sealing layer 7, so that the semiconductor device 1 and the substrate 6 are mechanically joined. As the encapsulating material, a composition mainly composed of a resin binder containing a cresol novolac type epoxy resin and a novolac type phenol resin (curing agent) and a filler composed of insulating particles is generally used.

[0008]

However, each of the mounting methods described above has the following problems.

With regard to the mounting methods (1) and (2), it is difficult to reduce the thermal stress generated by the difference in expansion coefficient between the semiconductor device and the substrate, so that the connection stability is maintained over a wide temperature range. There are limits to the applications that are required.

Regarding the mounting method (3), the use of a highly flexible resin material for the resin binder in the anisotropically conductive adhesive makes it possible to relieve thermal stress. In that case, the hygroscopicity of the binder As a result, the connection stability becomes a problem in a high humidity environment. It is also possible to reduce the thermal stress by adjusting the thermal expansion coefficient of the binder to the semiconductor device or substrate, but in that case, the initial connection reliability deteriorates because a large amount of low expansion coefficient filler is included. There is fear.

As for the mounting method (4), the thermal stress can be relaxed by making the conductive adhesive flexible so that the thermal expansion coefficient of the sealing material is adapted to the semiconductor device and the substrate. Therefore, it can be said that this mounting method (4) is a promising method among the methods in the flip chip mounting method.

However, also in the mounting method (4), the encapsulant composed of the composition obtained by mixing the cresol novolac type epoxy resin and the novolac type phenolic resin as described above has a high viscosity and has a high coefficient of thermal expansion to the semiconductor. In order to match the device and the substrate, it is necessary to increase the ratio of the amount of the filler in the encapsulant, resulting in the encapsulant having a high viscosity. Therefore, when the sealing material is filled between the semiconductor device and the substrate, it is necessary to heat the sealing material to 70 to 80 ° C. or higher to reduce the viscosity. As a result, productivity is poor,
In addition, there is a problem that the conductive connection portion is damaged when the encapsulating material is filled due to the thermal stress caused by the difference in the coefficient of thermal expansion when the temperature rises, and the connection reliability decreases.

On the other hand, it is also conceivable to use a resin binder mainly composed of polyepoxide and acid anhydride, which has a very low viscosity at room temperature, as a sealing material. However, if a large amount of filler is added to this resin binder in order to reduce the coefficient of thermal expansion, the viscosity of the sealing material is low but the thixotropy index becomes high. As a result, it is not possible to enclose between the semiconductor device and the substrate, or even if it can be enclosed, a large amount of air bubbles are included, and the thermal expansion of the encapsulant cured by these air bubbles becomes uneven depending on the location, and the connection reliability is improved. However, the encapsulant using a resin composed of a polyepoxide and an acid anhydride as a binder is not practical.

The object of the present invention is to investigate the limits of the viscosity and thixotropy characteristics required to obtain good sealing properties of the encapsulant, and to connect by using an encapsulant that satisfies such viscosity and thixotropy characteristics. An object of the present invention is to provide a semiconductor device having high reliability and high productivity and a mounting method thereof.

[0015]

The inventor of the present invention has found out that the reason why conventional materials are difficult to use as encapsulants is not only the viscosity but also the high thixotropy index of the encapsulant. For example, in a resin binder containing a polyepoxide and an acid anhydride, it was found that the fluidity is hindered by the interaction between the free acid in the acid anhydride and the polar group on the surface of the filler. Then, in view of the clarified fact, the following measures are taken in order to achieve the above object.

The means taken by the present invention has a viscosity of 100 Pa · s as a sealing material in the flip chip mounting method.
In the following, a composition having a thixotropy index of 1.1 or less is used, and a semiconductor device and a substrate are mechanically connected by a sealing layer obtained by curing the composition.

Specifically, in the present invention, the semiconductor device mounting body according to any one of claims 1 to 8, the semiconductor device mounting method according to any one of claims 9 to 20 and each of claims 21 to 28 are described. A first semiconductor device mounting encapsulant, comprising:
Measures relating to the second semiconductor device mounting sealing material described in No. 9 are taken.

As described in claim 1, a semiconductor device mounting body according to the present invention is provided on a semiconductor device having an electrode pad, a substrate having a terminal electrode, and an electrode pad of the semiconductor device. And a conductive adhesive layer which is made of a conductive adhesive having flexibility and electrically connects the bump electrode and the terminal electrode on the substrate, and has a viscosity of 10
It is provided with a sealing layer which is formed by curing a composition having a thixotropy index of 1.1 or less at 0 Pa · s or less and which fills a gap between the semiconductor device and the substrate and mechanically bonds the two.

With this structure, in the semiconductor device in which the semiconductor device is mounted on the substrate, the sealing layer for mechanically joining the semiconductor device and the substrate has a low viscosity (100 Pa · s or less in the mounting process in a liquid state). ) Has a low thixotropy index (1.1 or less), it quickly penetrates into the gap at the time of injecting the encapsulant in the mounting process and sufficiently penetrates into a small gap without generating bubbles, and the injection temperature can be lowered. It will be possible. Due to these properties, the electrical connection reliability such as the adhesion between the semiconductor device and the substrate and the thermal shock resistance are improved, and the productivity is also improved.

[0020] As described in claim 2, in the composition according to claim 1, the composition comprises a resin binder containing at least a polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst, and an insulating material. A rheology modifier having a function of inhibiting the interaction between the free acid in the carboxylic acid anhydride and the polar group on the surface of the filler. be able to.

Further, as described in claim 3, in claim 2, it is preferable that the rheology modifier contains a substance which selectively adsorbs a free acid in the carboxylic acid anhydride.

As described in claim 4, in claim 2, the rheology modifier is preferably composed of a Lewis base compound.

Further, as described in claim 5, in claim 2, the rheology modifier is a tertiary amine compound, a tertiary phosphine compound, a quaternary ammonium salt,
It is more preferable that at least one of a quaternary phosphonium salt and a heterocyclic compound containing a nitrogen atom in the ring is used.

In these structures (claims 2 to 5), since the sealing material is the one having a small coefficient of thermal expansion between the acid anhydride-curable epoxy resin and the insulating material as the main component, the sealing layer is used. The thermal stress acting on is reduced. Moreover, since a rheology modifier having a function of inhibiting the interaction between the free acid in the acid anhydride and the polar group on the surface of the filler is used, low viscosity and low thixotropy according to claim 1 are used. The index and will be realized.

As described in claim 6, in claim 2, the carboxylic acid anhydride in the resin binder is
It is preferable to include at least a cycloaliphatic acid anhydride.

In that case, as described in claim 7,
The cycloaliphatic acid anhydride may contain at least trialkyltetrahydrophthalic anhydride.

With the above constitutions (claims 6 and 7), good moisture resistance of the resin binder can be secured by utilizing the characteristics of the cycloaliphatic acid anhydride having low water absorption. Further, since the liquid resin binder has a low viscosity in the mounting process of the semiconductor device, the cost of the semiconductor device can be reduced by enclosing the encapsulating material in a short time.

As described in claim 8, in claim 1, it is preferable that the bump electrode of the semiconductor device is composed of a stud bump electrode having a two-step projection shape.

With this structure, the number of bump electrodes of the semiconductor device can be provided at a high density. Then, when mounting the semiconductor device on the substrate, when the bump electrode and the terminal electrode provided on the substrate are electrically connected to each other and the sealing material is injected into the gap between them, the viscosity is low. By using a sealing material having a low thixotropy index, it becomes possible to sufficiently spread the sealing material even in a small gap. Therefore, even in a semiconductor device formed by high-density mounting, the reliability of electrical connection and mechanical bonding between the semiconductor device and the substrate is improved.

According to a ninth aspect of the present invention, there is provided a semiconductor device mounting method, wherein a semiconductor device having an electrode pad is mounted on a substrate having a terminal electrode. Then, the first step of forming bump electrodes on the electrode pads of the semiconductor device, the second step of attaching a conductive adhesive near the tips of the bump electrodes, and the bump electrodes and the terminal electrodes of the substrate are performed. A third step of aligning the semiconductor device on the substrate and electrically connecting the bump electrode of the semiconductor device and the terminal electrode of the substrate through the conductive adhesive, and the viscosity is 100 Pa · s or less. And a fourth step of adjusting an encapsulant made of a composition having a thixotropy index of 1.1 or less, a fifth step of filling the encapsulant in a gap between the semiconductor device and the substrate, and the encapsulation. Cure the stopper And a sixth step of mechanically bonding the above semiconductor device and the substrate.

By this method, a low viscosity (100 Pa · s
In the following), a sealing material having a low thixotropy index (1.1 or less) is used, so that when the sealing material is injected in the mounting process, it quickly penetrates into the gap and sufficiently penetrates into a small gap without generating bubbles. It is also possible to lower the injection temperature. Therefore, the electrical connection reliability such as the adhesion between the mounted semiconductor device and the substrate and the thermal shock resistance are improved, and the time required for mounting is shortened.

As described in claim 10, claim 9
In the fourth step, as the composition, a resin binder containing at least a polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst,
It is possible to use a composition containing a filler made of an insulating material as a main component, and the rheology modifier interacts with a free acid in the carboxylic acid anhydride and a polar group on the surface of the filler. It is preferable to have a function of inhibiting

By this method, the viscosity and thixotropy index of the sealing material in the fifth step can be reduced. Further, since the main component of the encapsulating material is one having a small coefficient of thermal expansion between the acid anhydride-curable epoxy resin and the insulating material, the thermal stress acting on the encapsulating layer after mounting is reduced. .

According to claim 11, claim 9
In the above, as the rheology modifier, it is possible to use an agent that is also used as a curing catalyst for the two-component encapsulating material and that contains only a trace amount that does not exhibit a curing catalyst function.

According to this method, the rheology modifier is sealed when the sealing material is cured in the sixth step without starting the curing of the sealing material after the fourth step and before the fifth step. It is incorporated in the mesh structure that constitutes the resin blocking layer. Therefore, it is possible to prevent adverse effects such as a decrease in heat resistance and humidity resistance that may occur due to the addition of the rheology modifier.

As described in claim 12, claim 1
0, it is preferable that in the fourth step, at least a cycloaliphatic acid anhydride is included as the carboxylic acid anhydride in the resin binder.

In this case, as described in claim 13, at least a trialkyltetrahydrophthalic anhydride can be contained as the cycloaliphatic acid anhydride.

According to these methods (claims 12 and 13), since the cycloaliphatic acid anhydride has a low viscosity and a low water absorption rate, the encapsulating time in the sixth step is shortened and the moisture resistance is improved. Becomes higher.

As described in claim 14, claim 9
In the first step, it is preferable to form a two-step protruding stud bump electrode as the bump electrode of the semiconductor device.

According to this method, the number of bump electrodes of the semiconductor device can be provided at a high density, and in the fifth step, there is a low viscosity between the bump electrodes provided at a high density and the terminal electrodes on the substrate. The encapsulant with a low thixotropy index extends well into small gaps without producing bubbles. Therefore, the reliability of electrical connection and mechanical joining between the semiconductor devices mounted at high density and the substrate is improved.

As described in claim 15, claim 9
In the above fifth step, it is preferable that the sealing material is poured under room temperature conditions.

By this method, a semiconductor device package having extremely high electrical connection reliability such as improved thermal shock resistance due to reduced thermal stress can be obtained.

As described in claim 16, claim 9
In the above fifth step, it is preferable to pour the sealing material under a reduced pressure condition.

By this method, it is possible to obtain a semiconductor device mounting body with improved productivity and extremely high electrical connection reliability.

As described in claim 17, claim 9
In the fourth step, first, the carboxylic acid anhydride and a part of the filler can be mixed, and after the mixture is aged, the polyepoxide and the rest of the filler can be added.

By this method, the interaction between the free acid in the acid anhydride and the polar group on the surface of the filling material is relaxed, so that the low viscosity characteristic and the low thixotropic characteristic of the sealing material are realized.

As described in claim 18, claim 1
At 0, the rheology modifier may include a substance that selectively adsorbs the free acid in the carboxylic acid anhydride.

According to this method, when the free acid in the acid anhydride is selectively adsorbed by the rheology modifier, the interaction between the free acid and the polar group on the surface of the filler is hindered. Of low viscosity and low thixotropy.

As described in claim 19, claim 1
In No. 0, the rheology modifier is preferably a Lewis base compound.

[0050] Further, as described in claim 20, in claim 10, the rheology modifier is a tertiary amine compound, a tertiary phosphine compound, a quaternary ammonium salt, a quaternary phosphonium salt and nitrogen. It can be at least one of the heterocyclic compounds containing atoms in the ring.

According to these methods (claims 19 and 20), since the interaction between the free acid and the polar group on the surface of the filler is inhibited by the rheology modifier, the low viscosity property and low thixotropy of the encapsulant are obtained. The characteristics and are realized.

A first semiconductor device mounting encapsulant according to the present invention is a sealant for filling a gap between a semiconductor device and a substrate to connect the two, as described in claim 21. And a weight ratio of at least 80 including a polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst.
˜25% resin binder and 20% to 75% weight ratio filler made of insulating material. The rheology modifier has a function of inhibiting the interaction between the free acid in the carboxylic acid anhydride and the polar group on the surface of the filler.

With this structure, the sealing material has a low viscosity (100
Since it has a low thixotropic index (Pa.s or less) (1.1 or less), it quickly penetrates into the gap at the time of injecting the sealing material in the mounting process and sufficiently penetrates into a small gap without generating bubbles, and the injection temperature It can also be lowered. In addition, the latent curing catalyst ensures the stability of the encapsulant in the storage state and the practical curing acceleration function. Therefore, the electrical connection reliability such as the adhesion between the semiconductor device and the substrate in the mounting body and the thermal shock resistance are improved, and the productivity is also improved.

As described in claim 22, claim 2
In No. 1, it is preferable that the rheology modifier contains a substance that selectively adsorbs a free acid in a carboxylic acid anhydride.

Further, as described in claim 23, in claim 21, it is preferable that the rheology modifier is composed of a Lewis base compound.

As described in claim 24, claim 2
1, the rheology modifier is a tertiary amine compound, a tertiary phosphine compound, a quaternary ammonium salt, 4
It can be at least one of a secondary phosphonium salt and a heterocyclic compound containing a nitrogen atom in the ring.

With these configurations (claims 22 to 24), a sealing material having a small coefficient of thermal expansion between an acid anhydride-curable epoxy resin and an insulating material is used as a main component, so that it is formed. The thermal stress acting on the sealing layer in the mounting body is reduced. Moreover, as the rheology modifier, one having a function of inhibiting the interaction between the free acid in the acid anhydride and the polar group on the surface of the filler is used, so that low viscosity and low thixotropic index are realized. Will be done.

As described in claim 25, claim 2
1, the carboxylic acid anhydride in the resin binder may contain at least a cycloaliphatic acid anhydride.

In this case, as described in claim 26, the cycloaliphatic acid anhydride can contain at least trialkyltetrahydrophthalic anhydride.

With the above constructions (claims 25 and 26), good moisture resistance of the resin binder can be secured by utilizing the characteristics of the cycloaliphatic acid anhydride having low water absorption. Further, since the liquid resin binder has a low viscosity in the mounting process of the semiconductor device, the mounting cost can be reduced by enclosing the sealing material in a short time.

As described in claim 27, claim 2
In No. 1, it is preferable that the resin binder and the filler are liquefied.

With this structure, it becomes easy to uniformly disperse the filling material, and the sealing material is suitable for manufacturing LSI.

As described in claim 28, claim 2
1, the resin binder having an equivalent ratio of the carboxylic acid anhydride to the polyepoxide of 0.8 to 1.1.
And a composition in which the weight ratio of the curing catalyst to the whole resin binder is 0.3 to 3% and the weight ratio of the rheology modifier to the whole resin binder is 0.02 to 0.3%. Preferably.

A second semiconductor device mounting encapsulation material according to the present invention is a sealing material for filling a gap between a semiconductor device and a substrate to connect them, as described in claim 29. And a weight ratio of at least 80 including a polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst.
˜25% resin binder and 20% to 75% weight ratio filler made of insulating material. Then, the carboxylic acid anhydride and a part of the filler are first mixed, and the mixture is aged. Then, the polyepoxide and the rest of the filler are added to prepare the mixture.

According to this structure, since the interaction between the free acid in the carboxylic acid anhydride and the polar group on the surface of the filler is suppressed, the thixotropy index of the sealing material is lowered,
The same operation as is obtained.

[0066]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing a semiconductor device package according to the embodiment, and FIG. 2 is a partial cross-sectional view showing an enlarged detail of the vicinity of a connecting portion thereof. It is formed by the flip chip mounting method described above. 1 and 2, reference numeral 1 is an LSI
A semiconductor device such as a chip is shown, and reference numeral 2 is an electrode pad provided in a part of the semiconductor device 1. Reference numeral 3 indicates a bump electrode made of gold, and reference numeral 4 indicates a conductive adhesive layer composed of a composition (conductive adhesive) containing a special epoxy resin and conductive powder such as silver-palladium (AgPd) alloy as main components. Indicates. Reference numeral 6 indicates a substrate such as a ceramic substrate for mounting the semiconductor device 1, and reference numeral 5 indicates a terminal electrode on the substrate 6. Reference numeral 7 indicates a sealing layer composed of a sealing material containing an acid anhydride-curable epoxy resin as a main component. The encapsulant 7 has a thixotropy index of 1.1 or less and a viscosity of 100 Pa · s in a fluid state before curing, and the encapsulant is provided between the semiconductor device 1 and the substrate 6 by utilizing a capillary phenomenon. After injection, it is cured. However, the thixotropy index is an index represented by Δη / Δε when the shear rate is ε and the viscosity is η, and here,
The values are shown when the shear rate is 2 (1 / sec) to 20 (1 / sec).

FIG. 3 is a sectional view showing a semiconductor device mounting body formed by a flip-chip mounting method using so-called stud bump electrodes. The semiconductor device mounting body shown in FIG. 3 is basically the same as the semiconductor device mounting body shown in FIG. 1. However, in the semiconductor device mounting body shown in FIG. 3, the bump electrode 3 shown in FIG. The difference is that a stud bump electrode 14 having a two-step projection shape is used instead of. As described above, by adopting the flip chip mounting body using the stud bump electrodes 14, there is an advantage that it can be applied to a semiconductor device having a large number of electrode pads provided at a high density, as described later in detail.

Next, the stud bump electrode 14 shown in FIG.
FIG. 4A shows a flip chip mounting process using
Description will be made with reference to (e) and FIG. Figure 4 (a)
5A to 5E are cross-sectional views showing changes in the mounted body of the semiconductor device in the flip chip mounting process, and FIG. 5 is a flowchart showing the flow of the flip chip mounting process.
The mounting process will be described below along the steps shown in FIG.

First, in step ST1, a stud bump electrode 14 is formed on each electrode pad 2 of the semiconductor device 1 (LSI chip) using an Au wire, and then step ST2.
Then, the leveling process of pressing the flat surface with each stud bump electrode 14 is performed to align the positions of the tip surfaces of the stud bump electrodes 14.

Next, in step ST3, as shown in FIG.
As shown in (c), the semiconductor device 1 is positioned above the substrate 20 coated with the conductive adhesive 4a with the stud bump electrode 14 side facing downward, and then lowered from that state. After immersing the stud bump electrode 14 in the conductive adhesive 4a, the semiconductor device is pulled up and the conductive adhesive 4a is collectively transferred to each stud bump electrode 14.

Next, in steps ST4 and ST5, as shown in FIG.
As shown in (d), the semiconductor device 1 is mounted on the ceramic substrate 6 provided with a large number of terminal electrodes 5. At this time, each stud bump electrode 14 of the semiconductor device 1
And the terminal electrodes 5 on the substrate 6 are respectively aligned,
The conductive adhesive is hardened by heating to form the conductive adhesive layer 4
To form As a result, the stud bump electrode 14 of the semiconductor device 1 and the terminal electrode 5 of the substrate 6 are electrically connected.

Next, in step ST6, the connection state is inspected, and if the electrical connection state is defective (when it is NG), the chip (semiconductor device) is replaced in step ST7, and then step ST4 is performed. On the other hand, if the electrical connection state is good (when OK) while returning, the process proceeds to step ST8.

Next, in step ST8, a low viscosity (100
A sealing material made of a composition having a low thixotropy index (1.1 or less) at Pa · s or less) is injected into the gap between the semiconductor device 1 and the substrate 6 at room temperature to perform resin sealing of the connection portion. After that, in step ST9, the resin binder in the encapsulant is heated and cured by heating. At this time, FIG. 4 (e)
As shown in FIG. 5, the sealing layer 7 is formed, and the semiconductor device 1 and the substrate 6 are mechanically joined by the sealing layer 7.

Then, in step ST10, a final inspection is performed, and the flip chip mounting process is completed.

The encapsulant used in the flip chip mounting process has a low viscosity and a low thixotropy index.
The sealing material is quickly injected even at a low temperature of about room temperature, and the sealing material sufficiently spreads even in a small gap. Therefore, the time required for sealing can be shortened and the connection reliability of the joint portion connected via the conductive adhesive 4 can be maintained. Furthermore, since the encapsulant is a composition containing a fluidity-modified acid anhydride-curable epoxy resin and a filler such as fused silica as the main components, the thermal expansion coefficient after curing is also low. Have. As described above, since the thermal expansion coefficient of the sealing layer 7 is low, it is possible to suppress the thermal stress generated due to the thermal expansion coefficient difference between the silicon substrate forming the semiconductor device 1 and the alumina substrate forming the substrate 6, for example.
Further, since the sealing material composed of such an epoxy resin has high heat resistance and high adhesive strength, stable connection reliability can be achieved even in a high temperature and high humidity environment.

Since the conductive adhesive 4 has high flexibility, thermal stress can be relaxed and the connection stability is improved.

As described above, according to the above-mentioned flip chip mounting process, it becomes possible to connect the semiconductor device 1 and the substrate 6 with extremely high reliability and stability.

Although the bump electrode 3 is made of gold in the embodiment, its material is not limited to gold.
For example, it may be formed of other metal such as copper. Further, the shape of the bump electrode is not particularly limited to the stud bump electrode as described above, and any shape generally used for flip chip mounting can be applied. However, since the lateral spread of the conductive adhesive layer 4 can be suppressed by using the stud bump electrode as shown in FIGS. 3 and 4A to 4E, the packaging density is significantly improved. Can be achieved.

The material of the conductive adhesive 4 is not limited to the epoxy type, and any material may be used as long as it has flexibility. For example, rubber type such as SBR, NBR, IR, BR and CR, acrylic type, polyester type, polyamide type, polyether type, polyurethane type, polyimide type, silicone type and the like can be used. The material of the conductive powder contained in the conductive adhesive may be any one commonly used, for example, noble metal powder such as silver, gold and palladium, base metal powder such as nickel and copper, solder, silver palladium and the like. Alloy powders, composite powders such as silver-plated copper powder, and conductive non-metal powders such as carbon can be used. These conductive powders can be used alone or as a mixture of two or more kinds. The particle size and shape of these conductive powders are not particularly limited.

On the other hand, the encapsulant is mainly composed of a resin binder and a filler, and the resin binder contains polyepoxide, an acid anhydride and a rheology modifier as essential components. The polyepoxide in the resin binder used here is not particularly limited as a component, and those generally called an epoxy compound or an epoxy resin are used. For example, a bisphenol type epoxy resin represented by the general structural formula shown in FIG. 6, a novolac type epoxy resin, a glycidyl ether type epoxy resin, a glycidyl ester type epoxy resin, a glycidyl amine type epoxy resin, an alicyclic epoxy resin. , Biphenyl type epoxy resin,
Examples thereof include naphthalene type epoxy resin, styrene oxide, alkyl glycidyl ether, and alkyl glycidyl ester. These can be used alone or as a mixture of two or more kinds.

As the acid anhydride used here, those usually used as a curing agent for epoxy compounds and epoxy resins can be used. The most preferable example is trialkyltetrahydrophthalic anhydride having a structure represented by the general structural formula shown in FIG. Also,
Other preferable examples include cyclic aliphatic compounds such as methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, and methylhymic acid anhydride, which are liquid at 25 ° C. It is not limited to. These can be used alone or as a mixture of two or more kinds. In particular, by using the above as the main component of the resin binder, an encapsulant having very low viscosity, high heat resistance, high humidity resistance, and high adhesion can be obtained.

As the resin binder of the encapsulating material, in addition to the above essential components, heat resistance, moisture resistance, adhesion strength,
A third binder component may be added if necessary for the purpose of adjusting the coefficient of thermal expansion, adjusting the rheology, adjusting the reactivity, and the like.

The filler in the sealing material has an average particle size of 1
Any powder having a particle size of up to 50 μm may be used, but preferred examples include oxide compounds such as silica and alumina, nitride compounds such as aluminum nitride, carbonized compounds such as silicon carbide, and silicified compounds.
It is desirable that the material be thermally stable and have a low coefficient of thermal expansion. These filler components can be used in any combination of two or more. The amount of the filler is not particularly limited, but is preferably 20 to 80% by weight with respect to the total amount of the sealing material. By using these filler components, it is possible to realize a sealing material having excellent insulating properties and small thermal stress.

As the rheology modifier for modifying the fluidity of the encapsulant, the thixotropy index of the encapsulant is cut off by cutting off the interaction between the free acid in the acid anhydride and the polar group on the surface of the filler. The method is not particularly limited as long as it has a function of lowering

Preferred examples are: (1) Aging by partially mixing a part of the acid anhydride and the filler in advance (aging may be performed by heating to 100 ° C. or lower).
After that, a method of obtaining a sealing material by adding the polyepoxy compound and the rest of the filler and other additives (2) Add a substance that selectively adsorbs a free acid in an acid anhydride to the sealing material Method (3) A method in which a substance that interacts with the free acid stronger than the polar groups on the surface of the filler (such as a Lewis base compound that does not contain NH 3 groups or OH groups) is added to the encapsulating material .

However, the Lewis base compound here includes a tertiary amine compound, a tertiary phosphine compound, a quaternary ammonium salt such as tetrabutylammonium bromide, and a quaternary phosphonium such as tetrabutylfosnium benzotriazolate. Examples thereof include salts, melanin imidazole compounds, and other heterocyclic compounds containing a nitrogen atom in the ring. However, these are examples, and there are a great number of substances in the Lewis base compound, and such Lewis base compounds can be used alone or in combination of two or more kinds.

As the constituent components of the encapsulant, a rheology modifier such as a solvent, a dispersant and a leveling agent, an adhesion improver such as a coupling agent, and a reaction modifier such as a curing catalyst may be used, if necessary. it can.

The rheology modifier composed of a Lewis base compound such as an amine compound used in the present invention is also usually used as a curing catalyst for curing a polyepoxide with a carboxylic acid anhydride.

However, when the rheology modifier is used as a curing catalyst for the encapsulant, the reaction proceeds and gels even during storage at low temperature. Therefore, the encapsulant should be a two-liquid type that is mixed and used immediately before use. I have no choice. On the other hand, the encapsulating material for LSI must be a one-liquid type because the filler must be dispersed in a large amount and uniformly.

That is, the rheology modifier referred to in the present invention is used as a curing catalyst for a two-component encapsulant, but not as a one-component encapsulant.

On the other hand, if the additive amount is reduced to such a degree that it does not gel during storage, it cannot be applied as a curing catalyst for the one-component encapsulating material, but in that case, the curing promoting function is too low. However, a high degree of curing properties of the sealing material cannot be obtained under practical curing conditions.

The feature of the present invention is that a latent curing catalyst is used as a curing catalyst for providing storage stability as a one-component type and a practical curing promoting function, and it is usually used as a curing catalyst such as amine.
The substance used as a curing catalyst for the liquid encapsulant is used as a rheology modifier. Such a rheology modifier is added in such a small amount that it does not exhibit a curing function, but is added in an amount sufficient to improve the interface characteristics.

However, the latent curing catalyst means a catalyst whose catalytic activity is rapidly increased by applying energy such as heat. Usually, it is melted (liquefied) or dissociated by reaction when energy is applied. The activity is increased.

From the above viewpoints, the composition of the encapsulant and the resin binder in the encapsulant preferably have the following composition ratios.

Resin binder 80 to 25% by weight Filler component 20 to 75% by weight However, the polyepoxide, the carboxylic acid anhydride, the curing catalyst and the rheology modifier which are components in the resin binder may have the following component ratios. preferable.

Carboxylic anhydride / polyepoxide 0.8-1.1 equivalent ratio Curing catalyst / resin binder 0.3-3% by weight Rheology modifier / resin binder 0.02-0.3% by weight On the other hand, substrate 6 With respect to, a ceramic substrate made of alumina or the like, a substrate made of a material such as a metal glaze substrate, a glass substrate, a resin substrate such as glass epoxy, a polymer film substrate, or the like can be applied.

There is no special limitation on the material of the terminal electrode 5.

[0099]

EXAMPLE Next, a specific example carried out for investigating the characteristics of the semiconductor device obtained by the flip chip mounting process will be described.

(Embodiment 1) A semiconductor device having the structure shown in FIG. 1 is formed by the steps shown in FIGS. At that time, the bump electrode 3 is formed by gold plating. The conductive adhesive 4a is composed of a composition containing silver-palladium powder and a flexible epoxy resin as main components, and is heated to 120 ° C. to be cured. Further, the encapsulant having the composition a shown in Table 1 below is used to cure the encapsulant at 150 ° C.

Example 2 The stud bump electrode 14 shown in FIG. 3 is formed on the electrode pad 2 of the semiconductor device 1 by a wire bonder using gold. Subsequent steps are performed under the same steps and conditions as in Example 1 above.

Example 3 The semiconductor device 1 is mounted on the substrate 6 under the same conditions as in Example 1 except that the encapsulant is injected under reduced pressure.

Example 4 The semiconductor device 1 is mounted on the substrate 6 under the same conditions as in Example 2 except that the composition of the encapsulant is changed to the composition b shown in Table 1.

Example 5 The semiconductor device 1 is mounted on the substrate 6 under the same conditions as in Example 2 except that the substrate 6 is a glass epoxy substrate and the composition of the encapsulant is the composition c in Table 1.

(Example 6) The same as Example 2 except that the substrate 6 was a glass epoxy substrate, the conductive powder in the conductive adhesive 4 was silver powder, and the composition of the sealing material was the composition d of Table 1. The semiconductor device 1 is mounted on the substrate 6 under the same conditions.

(Embodiment 7) The substrate 6 is a glass substrate, the conductive adhesive 4 is mainly composed of silver powder and urethane resin, and the composition of the encapsulating material is the composition e of Table 1, and the encapsulating material is The semiconductor device 1 is mounted on the substrate 6 under the same conditions as in Example 2 above, except that the injection is performed under reduced pressure.

Example 8 The bump electrode 3 shown in FIG.
It is formed on the electrode pad 2 of the semiconductor device 1 by gold plating. In the subsequent steps, the semiconductor device 1 is mounted on the substrate 6 under the same steps and conditions as in the seventh embodiment.

(Comparative Example 1) The composition of the encapsulant is shown in Table 1 with the composition f
Semiconductor device 1 under the same conditions as in Example 2 except that
Are mounted on the substrate 6.

(Comparative Example 2) The composition of the encapsulant is the composition g in Table 1.
Semiconductor device 1 under the same conditions as in Example 2 except that
Are mounted on the substrate 6.

Table 1 below shows the contents of the above formulations a to g.

[0111]

[Table 1] Comparative Example 3 The semiconductor device 1 is mounted on the substrate 6 by the method shown in FIG. 9 of the conventional example. At this time, an alumina substrate is used as the substrate 6, the bump electrodes 3 are made of gold, and the terminal electrodes 5 are plated with indium. Bump electrode 3 and terminal electrode 5
After aligning and, the semiconductor device 1 is heated to 170 ° C. while being pressed with a jig to heat the bump electrode 3 and the terminal electrode 5.
And connect. Further, a silicone encapsulant (stressless type) is injected into the gap between the semiconductor device 1 and the substrate 6 and cured to form the encapsulation layer 10.

(Comparative Example 4) The semiconductor device 1 is mounted on the substrate 6 by the method shown in FIG. At that time, the bump electrode 3 is formed of gold, and the gold plating layer 11 is formed on the terminal electrode 5.
Is formed, and an acrylic encapsulant is coated thereon. After the bump electrodes 3 and the terminal electrodes 5 are aligned with each other, the sealing material is cured by irradiating ultraviolet rays or heating while pressing the semiconductor device 1 with a jig to form the sealing layer 12.

Comparative Example 5 The semiconductor device 1 is mounted on the substrate 6 by the method shown in FIG. 11 of the conventional example. At that time, the bump electrodes 3 are made of gold, and the substrate 6 is made of alumina. The substrate 6 is coated with an anisotropic conductive adhesive in which gold particles are dispersed in an epoxy binder. After aligning the bump electrodes 3 and the terminal electrodes 5, the anisotropic conductive adhesive is cured by ultraviolet irradiation or heating while pressing the semiconductor device 1 with a jig to form the anisotropic conductive adhesive layer 13. , The bump electrode 3 and the terminal electrode 5 are electrically and mechanically connected.

Table 2 below shows the viscosity and thixotropy index of the sealing materials used in the semiconductor devices shown in Examples 1 to 8 and Comparative Examples 1 to 5 and the time required to inject the sealing materials.

[0115]

[Table 2] In Examples 1 to 8, the injection time was as short as a few minutes or less, and it can be seen that it is suitable for practical use. On the other hand, Comparative Examples 1 and 2
Then, the injection time becomes as long as several tens of minutes or more, which is not suitable for practical use. It has been shown that such an injection time has a correlation with the viscosity and the thixotropy index.
That is, in each of Examples 1 to 8, low viscosity (100
Pa · s or less) and low thixotropic index (1.1
Since it has the following), the encapsulation time of the sealing material is short. On the other hand, when the viscosity exceeds 100 Pa · s as in Comparative Example 2 or the thixotropic index exceeds 1.1 as in Comparative Example 1, the injection time becomes extremely long. Therefore, it can be seen that when the viscosity of the sealing material is 100 Pa · s or less and the thixotropy index is 1.1 or less, the fluidity of the sealing material is improved to such an extent that it can be put to practical use.

In addition, in order to evaluate the connection stability of the semiconductor devices shown in Examples 1 to 8 and Comparative Examples 1 to 5, the results of the environmental resistance test and the environmental test methods and conditions are shown in Table 3 below. , Table 4 shows respectively.

[0117]

[Table 3]

[Table 4] The evaluation results shown in the above tables will be described below.

In each of Examples 1 to 8, no problem occurred in the connection stability even after each reliability test. Moreover, all of the sealing materials used there have a low viscosity (100 Pa).
-S or less) and a low thixotropy index (1.1 or less), and the encapsulation time is short. That is, regardless of the structure of the bump electrode, the type of substrate, various additives, the type of conductive adhesive, etc., the seal has a low viscosity (100 Pa · s or less) and a low thixotropy index (1.1 or less). It is shown that the use of the stopping material makes it possible to obtain a mounted body of a semiconductor device having excellent environmental resistance including thermal shock resistance and high productivity.

Further, in Examples 1 to 8, as a rheology modifier, a Lewis base having a function of interacting with a free acid stronger than a function of a polar group on the surface of the filler interacting with the free acid. Although a compound is used, these not only modify the rheology but also act as a reaction catalyst between the polyepoxide and the acid anhydride, thus enhancing the heat resistance and other environmental resistance of the encapsulant.

On the other hand, when the thixotropy index is high even when a low-viscosity encapsulant is used as in Comparative Example 1, it takes time to inject the encapsulant, and after that, when each reliability test is performed, the solder Some connection parts will be broken in the heat resistance test and the thermal shock test. It is considered that this is because air bubbles are included in the encapsulant layer during the injection of the encapsulant, and the thermal stress applied to the encapsulant layer during the test becomes non-uniform and damages the conductive connection.

Even when a conductive adhesive having a high flexibility is used, in Comparative Example 2 in which a high-viscosity resin such as a phenol-curing type epoxy resin is used as the sealing material, the sealing material is There is no choice but to inject the material by heating it, and at the time of injection, a connection part with a high connection resistance value appears. Further, when each reliability test is applied thereafter, in the thermal shock test, a portion where the connection portion is unstable may be broken. It is considered that this is because the viscosity of the sealing material is high and the joint portion of the conductive adhesive is damaged by the stress when the sealing material is injected.

In Comparative Examples 3 and 4, the connection is broken in a relatively short time in the thermal shock test. Further, in Comparative Example 4, the change in the connection resistance value is large in both the high humidity test and the solder heat resistance test. For these reasons, it is considered that disconnection occurs in Comparative Example 3 because the joint portion cannot relax the thermal stress. In Comparative Example 4, it is considered that the thermal stress generated from the sealing material is large and the water absorption rate of the sealing material is high.

In Comparative Example 5, the connection resistance value significantly increases in the high temperature storage test, high humidity storage test and solder heat resistance test. It is considered that this is because the binder of the anisotropic conductive adhesive has low moisture resistance and low adhesion at high temperature.
When an anisotropic conductive adhesive composed of a binder having a high humidity resistance is used, disconnection of the connection part occurs in the thermal shock test.

As can be seen from these evaluation results, the package of the semiconductor device according to the present invention has high reliability in any environment. However, conventionally, a resin binder containing a polyepoxide and an acid anhydride (curing agent) has not been generally used as a sealing material in a flip chip mounting process using a conductive adhesive. The reason is that when a resin binder made of polyepoxide and an acid anhydride (curing agent) is used as an encapsulant in mounting a semiconductor device, the thixotropy index of the encapsulant increases, so that a part of the gap between the semiconductor device and the substrate is increased. It seems that there is a problem that it can only be injected into.

Therefore, in the present invention, it was found that the problem of high thixotropic index is due to the interaction between the free acid contained in the acid anhydride and the polar group on the surface of the insulating filler (filler). , It has been found that this problem can be solved by taking measures to inhibit the interaction.

Another reason why the resin binder containing polyepoxide and acid anhydride (curing agent) has not been used as the encapsulant in the past is that polyepoxide and acid anhydride (curing agent) are used. It is generally known that the resin binders that are hydrolyzed in a high-humidity atmosphere will cause problems with the moisture resistance and reliability of the connection with a conductive adhesive when used as sealing materials. Probably because it was thought.

Therefore, in the present invention, as shown in each of the above examples, a resin binder using an acid anhydride (particularly containing trialkyltetraethylene hydrophthalic anhydride as a main component) as a curing agent is used as a semiconductor. It was confirmed that even when used as a sealing material in the flip-chip mounting process of the device, the sealing layer formed has sufficient moisture resistance to endure practical use. Moreover, since the encapsulant containing a resin binder having such a composition as a main component has a low viscosity and a low thixotropy index, it has a good property that it can penetrate quickly and into a small gap even when injected at a low temperature of about room temperature. Found out to have. From these characteristics, excellent characteristics such as high thermal shock resistance can be exhibited.

On the other hand, in the conventional semiconductor device mounting body in which the resin binder having the formulation f in Table 1 is used in the flip chip mounting process, the sealing material has a high thixotropy index, so that air bubbles are generated in the sealing layer. It is believed that the conductive connection will be damaged during the soldering heat resistance test and thermal shock test. Further, since the conventional semiconductor device mounting body in which the resin binder composed of the formulation g in Table 1 was used in the flip-chip mounting process had a high viscosity, 70 to 8
Since it is necessary to inject the resin binder while being heated to about 0 ° C., it is considered that the conductive connection is damaged and the impact resistance is deteriorated.

[0129]

According to the semiconductor device package of the present invention,
When the viscosity is 100 Pa · s or less, the thixotropy index is 1.
Since the composition of 1 or less is used, and the semiconductor device and the substrate are mechanically connected by the sealing layer obtained by curing the composition, the elimination of bubbles in the sealing layer and the reduction of thermal stress Therefore, it is possible to improve the reliability of electrical connection such as the adhesion between the semiconductor device and the substrate, the thermal shock resistance, and the productivity.

According to the semiconductor device mounting method of the present invention,
Since the semiconductor device is mounted on the substrate by using the encapsulating material, it is possible to manufacture a semiconductor device package having good electrical connection reliability while reducing the manufacturing cost.

According to the first semiconductor device mounting encapsulant of the present invention, a resin binder containing a polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst, and a filler made of an insulating material. Since the rheology modifier has a function of inhibiting the interaction between the free acid in the carboxylic acid anhydride and the polar group on the surface of the filler, it has a low viscosity and a low viscosity. A semiconductor device of the present invention having a thixotropy index, which can be used as an encapsulating material in which storage stability by a latent curing catalyst and a practical curing acceleration function are secured, and which has the excellent characteristics as described above. Can be used for manufacturing the mounted body.

According to the second semiconductor device mounting encapsulant of the present invention, a resin binder containing a polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst, and a filler made of an insulating material. As a component, first, carboxylic acid anhydride and a part of the filler are mixed, and after aging this mixture, the composition is adjusted by adding the rest of the polyepoxide and the filler, so that By suppressing the interaction between the free acid and the polar group on the surface of the filler, the same effect as in claim 21 can be exhibited.

[Brief description of drawings]

FIG. 1 is a sectional view showing a structure of a semiconductor device according to an embodiment.

FIG. 2 is a partial cross-sectional view showing in enlarged detail a connection portion of the semiconductor device shown in FIG.

FIG. 3 is a cross-sectional view showing the structure of a semiconductor device formed by the stud bump method according to the embodiment.

FIG. 4 is a cross-sectional view showing a structural change in a flip-chip mounting process of the semiconductor device according to the embodiment.

FIG. 5 is a flowchart showing a procedure of a flip-chip mounting process of the semiconductor device according to the embodiment.

FIG. 6 is a diagram showing a general structural formula of a bisphenol type epoxy resin in a resin binder used in an embodiment.

FIG. 7 is a diagram showing a general structural formula of trialkyltetrahydrophthalic acid in a resin binder used in an embodiment.

FIG. 8 is a cross-sectional view showing the structure of a conventional semiconductor device connected by solder bump electrodes.

FIG. 9 is a cross-sectional view showing the structure of a conventional semiconductor device connected by a low melting point metal layer.

FIG. 10 is a cross-sectional view showing a structure of a conventional semiconductor device connected by a curing shrinkage stress of a sealing resin.

FIG. 11 is a cross-sectional view showing the structure of a conventional semiconductor device connected by an anisotropic conductive adhesive.

FIG. 12 is a cross-sectional view showing a structure of a conventional semiconductor device connected by a conductive adhesive.

[Explanation of symbols]

 1 Semiconductor Device 2 Electrode Pad 3 Bump Electrode 4 Conductive Adhesive Layer 5 Terminal Electrode 6 Substrate 7 Sealing Layer 8 Solder Bump Electrode 9 Plating Layer 10 Sealing Layer 11 Gold Plating Layer 12 Sealing Layer 13 Anisotropic Conductive Adhesive Layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuru Harada 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Yoshihiro Bessho, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (29)

[Claims] 1. A semiconductor device having electrode pads, a substrate having terminal electrodes, bump electrodes provided on the electrode pads of the semiconductor device, and a bump made of a conductive adhesive having flexibility. A conductive adhesive layer for electrically connecting the electrode and the terminal electrode on the substrate, a viscosity of 100 Pa · s or less, and a thixotropy index of 1.
A package of a semiconductor device, comprising a sealing layer configured by curing a composition of 1 or less to fill a gap between the semiconductor device and the substrate and mechanically bond the two. 2. The semiconductor device package according to claim 1, wherein the composition comprises a resin binder containing at least a polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst, and an insulating material. A semiconductor containing a filler as a main component, wherein the rheology modifier has a function of inhibiting an interaction between a free acid in the carboxylic acid anhydride and a polar group on the surface of the filler. Device mount 3. The semiconductor device package according to claim 2, wherein the rheology modifier includes a substance that selectively adsorbs a free acid in a carboxylic acid anhydride. body. 4. The semiconductor device package according to claim 2, wherein the rheology modifier is a Lewis base compound. 5. The mounted body of the semiconductor device according to claim 2, wherein the rheology modifier is a tertiary amine compound, a tertiary phosphine compound, a quaternary ammonium salt, a quaternary phosphonium salt and a nitrogen atom. At least one of the heterocyclic compounds contained in the package of the semiconductor device. 6. The semiconductor device package according to claim 2, wherein the carboxylic acid anhydride in the resin binder contains at least a cycloaliphatic acid anhydride. 7. The semiconductor device package according to claim 6, wherein the cyclic aliphatic acid anhydride contains at least trialkyltetrahydrophthalic anhydride. 8. The semiconductor device package according to claim 1, wherein the bump electrode of the semiconductor device is a two-step projecting stud bump electrode. 9. A mounting method of a semiconductor device, wherein a semiconductor device having an electrode pad is mounted on a substrate having a terminal electrode, which comprises a first step of forming a bump electrode on the electrode pad of the semiconductor device. A second step of attaching a conductive adhesive to the vicinity of the tip of the bump electrode, the bump electrode and the terminal electrode of the substrate are aligned, the semiconductor device is set on the substrate, and the conductive adhesive is applied. The third step of electrically connecting the bump electrode of the semiconductor device and the terminal electrode of the substrate through the step of: the viscosity is 100 Pa · s or less and the thixotropy index is 1.
A fourth step of adjusting an encapsulant composed of a composition of 1 or less, a fifth step of filling the encapsulant into the gap between the semiconductor device and the substrate, and curing the encapsulant. And a sixth step of mechanically joining the semiconductor device and the substrate to each other. 10. The method for mounting a semiconductor device according to claim 9, wherein in the fourth step, a resin binder containing at least a polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst as the composition. And a filler composed of an insulating material as a main component, the rheology modifier interacts with the free acid in the carboxylic acid anhydride and the polar group on the filler surface. A method for mounting a semiconductor device, which has a blocking function. 11. The method for mounting a semiconductor device according to claim 9, wherein the rheology modifier contains a trace amount of a substance that is also used as a curing catalyst for the two-component encapsulant and does not exhibit a curing catalyst function. A method for mounting a semiconductor device, comprising: 12. The method for mounting a semiconductor device according to claim 10, wherein in the fourth step, at least a cycloaliphatic acid anhydride is contained as the carboxylic acid anhydride in the resin binder. Semiconductor device mounting method. 13. The method for mounting a semiconductor device according to claim 12, wherein in the fourth step, the cyclic aliphatic acid anhydride is used.
A method for mounting a semiconductor device, which comprises at least trialkyltetrahydrophthalic anhydride. 14. The method for mounting a semiconductor device according to claim 9, wherein in the first step, a two-step protruding stud bump electrode is formed as a bump electrode of the semiconductor device. How to implement. 15. The method for mounting a semiconductor device according to claim 9, wherein in the fifth step, the sealing material is poured under room temperature conditions. 16. The method for mounting a semiconductor device according to claim 9, wherein in the fifth step, the sealing material is poured under a reduced pressure condition. 17. The method for mounting a semiconductor device according to claim 9, wherein in the fourth step, first, the carboxylic acid anhydride and a part of the filler are mixed, the mixture is aged, and then the polyepoxide and the filler are filled. A method for mounting a semiconductor device, which comprises adding the rest of material. 18. The method for mounting a semiconductor device according to claim 10, wherein the rheology modifier includes a substance that selectively adsorbs a free acid in a carboxylic acid anhydride. Method. 19. The method for mounting a semiconductor device according to claim 10, wherein the rheology modifier is a Lewis base compound. 20. The method for mounting a semiconductor device according to claim 10, wherein the rheology modifier comprises a tertiary amine compound, a tertiary phosphine compound, a quaternary ammonium salt, a quaternary phosphonium salt, and a nitrogen atom. At least one of the heterocyclic compounds contained in the semiconductor device mounting method. 21. A sealing material for filling a gap between a semiconductor device and a substrate to connect them to each other, wherein a weight ratio of at least 80 including a polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst. ~ 25
% Resin binder and a filler of an insulating material in a weight ratio of 20 to 75%, the rheology modifier is a free acid in the carboxylic acid anhydride and a polar group on the surface of the filler. An encapsulant for mounting a semiconductor device, which has a function of hindering the interaction between the two. 22. The encapsulating material for mounting a semiconductor device according to claim 21, wherein the rheology modifier includes a substance that selectively adsorbs a free acid in a carboxylic acid anhydride. Sealant for mounting the device. 23. The encapsulant for mounting a semiconductor device according to claim 21, wherein the rheology modifier is a Lewis base compound. 24. The encapsulating material for mounting a semiconductor device according to claim 21, wherein the rheology modifier is a tertiary amine compound, a tertiary phosphine compound, a quaternary ammonium salt, a quaternary phosphonium salt and nitrogen. A sealing material for mounting a semiconductor device, which is at least one of heterocyclic compounds containing atoms in a ring. 25. The semiconductor device mounting encapsulant according to claim 21, wherein the carboxylic acid anhydride in the resin binder contains at least a cycloaliphatic acid anhydride. Sealing material. 26. The encapsulant for mounting a semiconductor device according to claim 25, wherein the cyclic aliphatic acid anhydride contains at least trialkyltetrahydrophthalic anhydride. Sealing material. 27. The encapsulating material for mounting a semiconductor device according to claim 21, wherein the resin binder and the filling material are liquefied. 28. The encapsulating material for mounting a semiconductor device according to claim 21, wherein the resin binder has an equivalent ratio of the carboxylic acid anhydride to the polyepoxide of 0.8 to 1.1, and the curing catalyst. Of the rheology modifier to the whole resin binder is 0.02 to 0.3%, and the weight ratio to the whole resin binder is 0.02 to 0.3%. Mounting encapsulant. 29. An encapsulating material for filling a gap between a semiconductor device and a substrate to connect them to each other, wherein a weight ratio of at least polyepoxide, a carboxylic acid anhydride, a rheology modifier and a latent curing catalyst is 80. ~ 25
% Resin binder and a filler of insulating material in a weight ratio of 20 to 75%. First, a carboxylic acid anhydride and a part of the filler are mixed, and the mixture is aged, followed by polyepoxide and filling. A sealing material for mounting a semiconductor device, which is adjusted by adding the rest of the material.