JP2892348B1 - Semiconductor unit and semiconductor element mounting method - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To improve reliability of connection between a semiconductor element and a circuit board in a semiconductor unit in which a semiconductor element is mounted face down on a circuit board. SOLUTION: In a mounting body of the semiconductor element 1 in which the semiconductor element 1 is mounted face down on a circuit board 4 using a conductive adhesive 3, a liquid is filled in a porous space 13 of a bonding layer 6 of the porous conductive adhesive. Is impregnated with the sealing resin 7 to obtain a sealing resin filling layer 10 completely filled without voids.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor unit in which a semiconductor element is mounted on a circuit board in a face-down state, and a method for mounting a semiconductor element suitable for the semiconductor unit.

[0002]

2. Description of the Related Art Conventionally, when a semiconductor element is mounted on a circuit board, soldering has been widely used. However, in recent years, the space between the connection terminals has been narrowed due to the miniaturization of the package of the semiconductor element and the increase in the number of connection terminals, and it has become increasingly difficult to deal with the conventional soldering technology.

[0003] Therefore, a method has been devised in which a bare semiconductor element is directly mounted on a circuit board to reduce the mounting area and to efficiently use it. For example, when connecting a semiconductor element to a circuit board, a vapor deposition film of an adhesion metal or a diffusion preventing metal is formed in advance on a terminal electrode of the semiconductor element, and a solder bump electrode formed by plating is formed thereon. Next, the semiconductor element is placed face down and heated to a high temperature to fuse the solder to the connection electrodes of the circuit board. This mounting method is considered to be an effective method because the mechanical strength after connection is high and the connection can be made at once (for example, the Industrial Research Council, published on January 15, 1980, edited by the Japan Microelectronics Association) , “IC mounting technology”).

Further, as shown in US Pat. No. 5,121,190 and Japanese Patent Application Laid-Open No. 6-61303, a mounting method using an encapsulant and a semiconductor unit have been proposed in order to secure the stability of a joint portion by soldering. ing. Less than,
With reference to FIG. 5, a description will be given of this conventional semiconductor element mounting method and a semiconductor unit mounted thereby. FIG. 5 is a sectional view of a main part of a conventional semiconductor unit mounted face down.

As shown in FIG. 5, a conventional semiconductor unit mounted face down includes a semiconductor element 1, a terminal electrode 2 of the semiconductor element 1, a circuit board 4, and a surface of the circuit board 4. The semiconductor device 1 includes a connection electrode 5, a solder joint 15 that joins the connection electrode 5 and the terminal electrode 2, and a sealing resin 16 that seals the semiconductor element 1.

Next, a method for mounting a semiconductor element for forming the above-mentioned conventional semiconductor unit will be described with reference to FIG. First, the semiconductor element 1 having the solder projecting electrodes 17 is mounted on the circuit board 4 in a face-down state, and the solder projecting electrodes 17 are positioned at predetermined positions of the connection terminals 5 (FIG. 6A). Next, the solder is melted by heating to a high temperature of 200 to 300 ° C., the protruding electrode 17 of the solder is joined to the connection terminal 5, and the semiconductor element 1 is fixed to the circuit board 4 by the solder joint 15 (FIG. 6 ( b)). Thereafter, a liquid sealing resin 7 is poured into a gap between the semiconductor element 1 and the circuit board 4 (FIG. 6C), and the liquid sealing resin is filled.
The sealing resin is solidified by being heat-cured to a degree (FIG. 6D). Thus, the mounting of the semiconductor element 1 on the circuit board 4 is completed.

[0007]

However, the conventional methods of mounting a semiconductor unit and a semiconductor element have the following problems.

First, when the liquid sealing resin 7 is poured into the gap between the semiconductor element 1 and the circuit board 4 as a metal lump, the solder bonding portion 15 is placed behind the solder bonding portion 15 (the liquid sealing resin 7). The gap 18 in which the liquid sealing resin does not go around is formed, or the gap 18 in which the liquid sealing resin does not go around is divided into bubbles 19 in the liquid sealing resin. Or Therefore, the liquid sealing resin filled in the gap between the semiconductor element 1 and the circuit board 4 becomes the liquid sealing resin 20 containing voids, and when this is thermally cured, thermal stress caused by thermal expansion of the voids is reduced. Joins the solder joint 15,
Large internal distortion occurs.

Second, when using a semiconductor unit,
In the gap between the semiconductor element 1 and the circuit board 4, there is a sealing resin filling layer 21 which is cured while leaving voids, and the thermal stress generated by the thermal expansion of the voids in the sealing resin filling layer causes soldering. When the semiconductor unit is used in a high-temperature region (for example, at the time of work such as soldering) after leaving the semiconductor unit unattended, it is hardened while leaving a void in the gap between the semiconductor element 1 and the circuit board 4. A new thermal stress caused by the moisture in the voids of the resin filling layer 21 becoming water vapor and thermally expanding is applied to the solder joint 15.

Due to the above problem, the conventional semiconductor element mounting method and the semiconductor unit mounted by the method have low reliability of connection between the semiconductor element 1 and the circuit board 4 and are not very practical. In particular, in the case of a two-dimensional area arrangement of terminal electrodes of a semiconductor element corresponding to the recent increase in the number of terminals of a semiconductor element (conventionally, a one-dimensional arrangement of four sides of a semiconductor device) Many connection points between the semiconductor element 1 and the circuit board 4 exist inside the semiconductor device 1, and the above-mentioned problems become more serious.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and provides a semiconductor unit and a method of mounting a semiconductor element which improve the reliability of connection between a semiconductor element and a circuit board. It is intended for.

[0012]

To achieve the above object, a first present invention (corresponding to the first aspect of the present invention).
A circuit board, a semiconductor element mounted face-down on the circuit board, a bonding layer for electrically and mechanically connecting a terminal electrode of the semiconductor element and a connection electrode of the circuit board, An element and a filling layer of a sealing resin filled in a gap between the circuit board, the bonding layer,
A semiconductor unit comprising a porous conductive material portion and a part of the sealing resin present in a porous space of the conductive material portion.

A second aspect of the present invention (corresponding to the second aspect of the present invention) is characterized in that the semiconductor element has a protruding electrode between the terminal electrode and the bonding layer. 3 is a semiconductor unit of the present invention.

According to a third aspect of the present invention (corresponding to the third aspect of the present invention), the thermal expansion coefficient of the bonding layer is substantially equal to the thermal expansion coefficient of the filling layer. Or it is the semiconductor unit of the second invention.

According to a fourth aspect of the present invention (corresponding to the fourth aspect of the present invention), the sealing resin contains at least an organic resin and an inorganic filler. 3 is a semiconductor unit of the present invention.

A fifth aspect of the present invention (corresponding to the fifth aspect of the present invention) is characterized in that the inorganic filler includes one whose size is larger than the porous space. 3 is a semiconductor unit according to the invention.

According to a sixth aspect of the present invention (corresponding to the sixth aspect of the present invention), a part of the sealing resin present in the porous space contains the organic resin and does not contain the inorganic filler. A fifth aspect of the present invention is the semiconductor unit according to the fifth aspect.

According to a seventh aspect of the present invention (corresponding to the seventh aspect of the present invention), the inorganic filler includes a filler whose size is smaller than that of the porous space. 3 is a semiconductor unit according to the invention.

An eighth aspect of the present invention (corresponding to the eighth aspect of the present invention) is characterized in that a part of the sealing resin present in the porous space contains the organic resin and the inorganic filler. 7 is a semiconductor unit according to a seventh aspect of the present invention.

A ninth aspect of the present invention (corresponding to the ninth aspect of the present invention) is characterized in that a main component of the porous conductive material portion is a conductive adhesive. Or the semiconductor unit of the present invention.

According to a tenth aspect of the present invention (corresponding to the tenth aspect of the present invention), the main component of the porous conductive material portion is a porous metal.
Or the semiconductor unit of the present invention.

An eleventh invention (corresponding to the invention according to claim 11) is a method for mounting a semiconductor element on a circuit board in a face-down state, wherein the terminal electrode of the semiconductor element and the circuit An electrode connection step of forming a porous conductive material portion by electrically connecting a connection electrode of the substrate using a porous conductive material; and after the electrode connection step, the semiconductor element and the circuit board A resin filling step of filling the gap with a liquid sealing resin, and simultaneously with the resin filling step, an impregnation step of impregnating the liquid sealing resin into a porous space of the porous conductive material portion, And a resin curing step of curing the liquid sealing resin after the impregnation step.

A twelfth aspect of the present invention (corresponding to the twelfth aspect of the present invention) is a method of mounting a semiconductor element on a circuit board in a face-down state, wherein the terminal electrode of the semiconductor element and the circuit An electrode connection step of electrically connecting a connection electrode of the substrate with a conductive adhesive,
After the electrode connection step, the conductive adhesive is cured,
A conductive material portion forming step of forming a porous conductive material portion, and a resin filling step of filling a gap between the semiconductor element and the circuit board with a liquid sealing resin after the conductive material portion forming step. An impregnating step of impregnating the porous space of the porous conductive material portion with the liquid sealing resin simultaneously with the resin filling step, and a resin curing step of curing the liquid sealing resin after the impregnation step And a step of mounting the semiconductor element.

According to a thirteenth aspect of the present invention (corresponding to the thirteenth aspect of the present invention), the conductive adhesive comprises at least a solvent, an organic resin, and a conductive filler. 4 is a mounting method of the semiconductor element of the present invention.

A fourteenth aspect of the present invention (corresponding to the fourteenth aspect of the present invention) is characterized in that the liquid sealing resin has no solubility in the conductive adhesive after curing. A thirteenth method of mounting a semiconductor device according to the present invention.

A fifteenth aspect of the present invention (corresponding to the fifteenth aspect of the present invention) is characterized in that the liquid sealing resin contains at least an organic resin and an inorganic filler.
A mounting method of a semiconductor device according to any one of the present invention.

According to a sixteenth aspect of the present invention (corresponding to the sixteenth aspect of the present invention), in the impregnating step, the liquid sealing resin is impregnated so that the porous space is not impregnated with the inorganic filler. A fifteenth aspect of the present invention is a method for mounting a semiconductor device according to the present invention.

According to a seventeenth aspect of the present invention (corresponding to the seventeenth aspect of the present invention), in the impregnation step, the liquid sealing is performed such that the organic resin and the inorganic filler are impregnated in the porous space. A fifteenth aspect of the present invention is a method for mounting a semiconductor element according to the present invention, which comprises impregnating a sealing resin.

An eighteenth aspect of the present invention (corresponding to the eighteenth aspect of the present invention) includes, before the electrode connecting step, a projecting electrode forming step of forming a projecting electrode on the terminal electrode. The method according to any one of the eleventh to seventeenth aspects, wherein in the step, the terminal electrode and the connection electrode are electrically connected to each other via the protruding electrode. .

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor unit and a method of mounting a semiconductor element suitable for the present invention are mounted on a circuit board in a face-down state, and a terminal electrode of the semiconductor element and a connection electrode of the circuit board are electrically conductive. In a state where a porous space is formed in the conductive material, a liquid sealing resin filling a gap between the bonding layer semiconductor element and the circuit board is impregnated in the porous space of the conductive material. Then, the liquid sealing resin is cured. Accordingly, when the liquid sealing resin is poured into the gap between the semiconductor element and the circuit board, the liquid sealing resin can pass through the porous conductive material. The liquid sealing resin can also be filled (with respect to the direction in which the liquid sealing resin travels), and a filling layer without voids or bubbles can be obtained in the liquid sealing resin. As a result, when the liquid sealing resin is thermally cured, thermal stress generated by thermal expansion of voids and voids of bubbles can be completely eliminated from being applied to the joint made of the conductive material, and the semiconductor element and the circuit board can be eliminated. Can be surely joined. In addition, since a void-free sealing resin filling layer is obtained in the gap between the semiconductor element and the circuit board, even when a semiconductor unit is used, thermal stress caused by thermal expansion of the void and voids in a high-temperature region may be generated. It is possible to completely eliminate the application of new thermal stress caused by the thermal expansion of the moisture as water vapor into the joint made of the conductive material, and to significantly improve the stability of the joint.

An embodiment of the present invention will be described below with reference to the drawings.

(First Embodiment) First, the first embodiment of the present invention will be described.
An embodiment will be described with reference to the drawings.

FIG. 1 is a cross-sectional view showing steps of a method for mounting a semiconductor device according to a first embodiment of the present invention, and FIG. 1 (e) shows a semiconductor device according to the first embodiment of the present invention. FIG. 3 is a sectional view of a main part showing a configuration of a unit. Also,
FIG. 2 is a cross-sectional view of a main part showing a bonding layer of a porous conductive adhesive, and FIG. 3 is a cross-sectional view of a main part showing a state in which a liquid sealing resin is impregnated in the bonding layer of the porous conductive adhesive. It is.

As shown in FIG. 1E, the semiconductor unit according to this embodiment includes a semiconductor element 1, a terminal electrode 2 formed on the semiconductor element 1, a circuit board 4, and a surface of the circuit board 4. The formed connection electrode 5, a bonding layer for electrically and mechanically connecting the terminal electrode 2 and the connection electrode 5, and a sealing resin filling layer completely filled in a gap between the semiconductor element 1 and the circuit board 4. 10 or the like. FIG. 1 (a)
In (d), 3 is a solvent-type conductive adhesive used for mounting the semiconductor element 1, 6 is a bonding layer of a porous conductive adhesive, 7 is a liquid sealing resin, and 8 is a liquid sealing resin. The bonding layer 9 of the conductive adhesive impregnated with the sealing resin 7 is a liquid sealing resin completely filled in the gap between the semiconductor element 1 and the circuit board 4.

Next, a method of mounting the semiconductor device according to the present embodiment will be described. First, a solvent-type conductive adhesive 3 is applied to the terminal electrodes 2 of the semiconductor element 1 in advance. The solvent-type conductive adhesive 3 is a composition containing at least a solvent (for example, BCA), an organic resin (for example, phenoxy resin), and a conductive filler (for example, Ag powder). A typical example of the solvent-type conductive adhesive 3 is “UNIMEC H9806-1” manufactured by Namics Corporation. Then, the semiconductor element 1 is positioned face down (downward) to be aligned with the connection electrode 5 of the circuit board 4, the semiconductor element 1 is mounted on the circuit board 4, and the terminal electrode 2 of the semiconductor element 1 is connected to the circuit board 4. Are electrically connected by the conductive adhesive 3 (FIG. 1A). The steps after the alignment correspond to the electrode connecting step of the present invention.

Thereafter, the solvent-type conductive adhesive 3 is cured (FIG. 1B). At this time, the solvent type conductive adhesive 3
By curing, the solvent contained evaporates, and as shown in FIG. 2, the conductive filler 11 and the organic resin 12 remain,
A bonding layer 6 of a porous conductive adhesive having a porous space 13 is formed. This step corresponds to the conductive material part forming step of the present invention.

Next, the gap between the semiconductor element 1 and the circuit board 4 is filled with a liquid sealing resin 7 (for example, a composition containing a bisphenol F type liquid resin, a phenolic compound curing agent, and a silica filler) (FIG. 1). 1 (c)). A typical example of the liquid sealing resin 7 is “Chipcoat 8408” manufactured by Namics Corporation. At this time, the liquid sealing resin 7 is impregnated in the porous space 13 of the bonding layer 6 of the porous conductive adhesive, and the bonding layer 8 of the conductive adhesive impregnated with the liquid sealing resin 7 is obtained. At the same time, since the liquid sealing resin 7 flows through the porous conductive adhesive bonding layer 6, the liquid sealing resin 7 is impregnated with the conductive adhesive bonding layer 8 impregnated with the liquid sealing resin (liquid sealing resin 8). 7 (in the direction of travel of 7), the liquid sealing resin 7 can be filled, and a filling layer of the completely filled liquid sealing resin 9 without voids and bubbles can be obtained (FIG. 1D). At this time, in order to maintain electrical connection by the conductive adhesive, a liquid sealing resin 7 having no solubility in the conductive adhesive is used. This step corresponds to the resin filling step and the impregnation step of the present invention.

At this time, if the silica filler contained in the liquid sealing resin 7 is made larger than the porous space 13 of the bonding layer, the organic resin contained in the liquid sealing resin 7 is filled in the porous space 13 of the bonding layer. Only the resin is impregnated. In this case, an effect is obtained that the electrical bonding by the conductive adhesive is not hindered at all.

Thereafter, the completely filled liquid sealing resin 9
By hardening, a completely filled cured sealing resin filling layer 10 having no voids or bubbles in the gap between the semiconductor element 1 and the circuit board 4 is obtained, and is integrated with the sealing resin. A bonding layer of a conductive adhesive is obtained (FIG. 1).
(E)). At this time, in the bonding layer of the conductive adhesive integrated with the sealing resin, the sealing resin is impregnated into the porous space 13 of the porous conductive adhesive as shown in FIG. Therefore, a semiconductor unit integrated with the sealing resin filling layer 10 is obtained. This step corresponds to the resin curing step of the present invention.

In the resin filling step, the liquid sealing resin 7 impregnated in the porous space 13 of the porous conductive adhesive bonding layer 6 is replaced with the conductive adhesive bonding layer impregnated with the liquid sealing resin. Since it also flows behind (in the direction of travel of the liquid sealing resin 7) 8, a completely filled liquid sealing resin 9 is obtained. Therefore, in the curing step of the liquid sealing resin 7, since the liquid sealing resin 9 completely filled in the gap between the semiconductor element 1 and the circuit board 4 has no voids or voids of air bubbles, the curing step is performed. Thermal stress on the joint due to thermal expansion of voids generated therein can be completely eliminated, and the joining between the semiconductor element 1 and the circuit board 4 can be ensured.

In the semiconductor unit formed as described above, the porous space in the bonding layer between the terminal electrode 2 of the semiconductor element 1 and the connection electrode 5 of the circuit board 4 is filled with a sealing resin, and The gap between the semiconductor element 1 and the circuit board 4 is completely filled with the cured sealing resin filling layer 10 without any voids or voids. Therefore, even when the semiconductor unit is used, the thermal stress generated by the thermal expansion of the voids in the filling layer of the sealing resin is not applied to the bonding layer. Even when used in a high-temperature region, it is possible to completely eliminate the new thermal stress generated by the moisture that has penetrated into the voids and become a water vapor and thermally expanded, thereby completely eliminating the semiconductor element 1 and the circuit. Substrate 4
A highly reliable semiconductor unit can be obtained.

At this time, the sealing is performed such that the bonding layer of the conductive adhesive integrated with the sealing resin and the sealing resin filling layer 10 in the gap between the semiconductor element 1 and the circuit board 4 have the same coefficient of thermal expansion. It is desirable to adjust the compounding amount of the silica filler in the resin.

(Second Embodiment) Next, a second embodiment of the present invention will be described.
An embodiment will be described with reference to the drawings. The semiconductor unit according to the present embodiment is the same as the first unit except that the semiconductor element has the bump electrode of the present invention.
This is the same as the semiconductor unit in the embodiment. Therefore, in the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. Also, unless otherwise specified,
It is the same as the first embodiment.

FIG. 4 is a sectional view showing a main part of a semiconductor unit according to a second embodiment of the present invention. Substantially the same as the first embodiment, except that the projecting electrode 14 is formed on the terminal electrode 2 of the semiconductor element 1 as compared with the above-described first embodiment. Configuration.

Next, a method of mounting the semiconductor device according to the present embodiment will be described. The method for mounting a semiconductor element in the present embodiment includes, before the electrode connecting step of the method for mounting a semiconductor element in the first embodiment, a step of forming a bump electrode 14 on the terminal electrode 2, In the electrode connecting step, the procedure is substantially the same as that of the first embodiment, except that the terminal electrode 2 and the connecting electrode 5 are electrically connected to each other by the bonding layer via the bump electrode 14. is there.

Au or the like is used as the material of the bump electrode 14. By forming the protruding electrodes 14 on the terminal electrodes 2, in addition to the effects of the first embodiment, it is possible to restrict the spread of the conductive adhesive 3 when the semiconductor element 1 is mounted on the circuit board 4. And bonding at a fine pitch becomes possible. Further, the gap between the semiconductor element 1 and the circuit board 4 can be widened by the height of the protruding electrode 14, and the thermal stress can be further reduced.

In the mounting method of the semiconductor element according to the first and second embodiments, the conductive adhesive 3
Is applied to the semiconductor element 1 side, but the same effect can be obtained by applying the conductive adhesive 3 to the connection electrode 5 side of the circuit board 4.

The conductive adhesive 3 is not limited to a solvent-type conductive adhesive, but has a porous space after curing.
Any material may be used as long as it has electrical continuity.

The material for joining the semiconductor element 1 to the circuit board 4 is not limited to the porous conductive adhesive, but may be any porous conductive member, for example, a porous metal. . In addition, if the size of the inorganic filler such as silica mixed with the sealing resin layer 9 to adjust the thermal expansion coefficient is smaller than the size of the porous space 13 of the porous conductive adhesive, the use of the inorganic filler becomes conductive. The filling layer of the sealing resin containing the inorganic filler can be formed behind the bonding layer of the adhesive, and the effect can be further exhibited.

In the method of mounting a semiconductor element according to the first and second embodiments, the terminal electrodes of the semiconductor element and the connection electrodes of the circuit board are electrically connected using a conductive adhesive. The electrode connection step and, after the electrode connection step, have been described as including a conductive material part forming step of curing the conductive adhesive to form a porous conductive material part. Instead of the step of forming the conductive material portion, a porous material having a porous space and an adhesive property is used to electrically connect the terminal electrode of the semiconductor element and the connection electrode of the circuit board, thereby forming a porous material. A similar effect can be obtained even if a step of forming the conductive material portion is included.

[0051]

As is apparent from the above description, the present invention can provide a semiconductor unit and a method for mounting a semiconductor element which improve the reliability of connection between the semiconductor element and the circuit board.

That is, in the semiconductor unit of the present invention, the joint between the semiconductor element and the circuit board and the filling part of the gap between the semiconductor element and the circuit board are integrated. As a result, even when the semiconductor unit is used, thermal stress caused by thermal expansion of the void and new thermal stress caused by thermal expansion of moisture in the void in a high-temperature region as steam become bonded by the conductive member. It is possible to completely prevent the semiconductor element and the circuit board from being joined to each other. In addition, the conductive member of the joint portion,
Since the space that has been porous is filled with the sealing resin, the strength and adhesion of the joint between the semiconductor element and the conductive member of the circuit board can be increased, and the joining stability can be improved.

Further, by providing the protruding electrode on the terminal electrode of the semiconductor element, the spread of the conductive member when the semiconductor element is mounted on the circuit board can be restricted, and bonding at a fine pitch can be performed. . In addition, the gap between the semiconductor element and the circuit board can be widened by the height of the protruding electrode, and the thermal stress can be further reduced.

Further, by making the thermal expansion coefficients of the bonding layer and the sealing resin layer the same, it is possible to prevent the occurrence of peeling or cracking at the interface between the bonding layer and the sealing resin layer.

Further, by including an inorganic filler larger than the porous space of the porous conductive member in the sealing resin layer, it becomes easy to adjust the thermal expansion coefficient of the bonding layer and the sealing resin layer.

On the other hand, the mounting method of the semiconductor device of the present invention is as follows.
The semiconductor unit of the present invention can be easily manufactured.

Further, as a porous conductive member, a solvent-type conductive adhesive containing at least a solvent, an organic resin, and a conductive filler is cured to easily form a porous space by volatilization of the solvent. Can be.

Further, by using a liquid sealing resin which does not dissolve in the conductive adhesive after curing, damage of the bonding layer once formed by injection of the sealing resin is prevented. be able to.

[Brief description of the drawings]

FIG. 1 is a fragmentary cross-sectional view showing a step in a method for mounting a semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a main part showing a bonding layer of a porous conductive adhesive according to the first embodiment of the present invention.

FIG. 3 is an essential part cross-sectional view showing a state in which a liquid sealing resin is impregnated in a bonding layer of a porous conductive adhesive according to the first embodiment of the present invention.

FIG. 4 is a fragmentary cross-sectional view showing a configuration of a semiconductor unit according to a second embodiment of the present invention.

FIG. 5 is a sectional view of a main part showing a configuration of a conventional semiconductor unit mounted face-down.

FIG. 6 is a cross-sectional view of a main part showing steps of a conventional method for mounting a semiconductor element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor element 2 Terminal electrode 3 Solvent type conductive adhesive 4 Circuit board 5 Connection electrode 6 Porous conductive adhesive bonding layer 7 Liquid sealing resin 8 Conductive adhesive impregnated with liquid sealing resin Bonding layer 9 Completely filled liquid sealing resin 10 Filled layer of cured sealing resin 11 Conductive filler 12 Organic resin 13 Porous space 14 Protruding electrode 15 Solder joint 16 Sealing resin 17 Solder protruding electrode 18 Liquid Voids in which the sealing resin does not flow around 19 Bubbles in the liquid sealing resin 20 Liquid sealing resin containing voids 21 Filling layer of the sealing resin cured while leaving voids

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01L 21/60 311 H01L 23/28

Claims (18)

(57) [Claims] 1. A circuit board, a semiconductor element mounted face-down on the circuit board, and a bonding layer for electrically and mechanically connecting a terminal electrode of the semiconductor element and a connection electrode of the circuit board. And a filling layer of a sealing resin filled in a gap between the semiconductor element and the circuit board, wherein the bonding layer exists in a porous conductive material portion and a porous space of the conductive material portion. A semiconductor unit comprising a part of the sealing resin. 2. The semiconductor unit according to claim 1, wherein the semiconductor element has a protruding electrode between the terminal electrode and the bonding layer. 3. The semiconductor unit according to claim 1, wherein a thermal expansion coefficient of the bonding layer is substantially equal to a thermal expansion coefficient of the filling layer. 4. The sealing resin according to claim 1, wherein the sealing resin contains at least an organic resin and an inorganic filler.
The semiconductor unit according to any one of the above. 5. The semiconductor unit according to claim 4, wherein the inorganic filler includes a filler whose size is larger than that of the porous space. 6. The semiconductor unit according to claim 5, wherein a part of the sealing resin present in the porous space contains the organic resin and does not contain the inorganic filler. 7. The semiconductor unit according to claim 4, wherein the inorganic filler includes a filler whose size is smaller than that of the porous space. 8. The semiconductor unit according to claim 7, wherein a part of the sealing resin existing in the porous space contains the organic resin and the inorganic filler. 9. The method according to claim 1, wherein a main component of the porous conductive material portion is a conductive adhesive.
The semiconductor unit according to any one of the above. 10. The method according to claim 1, wherein a main component of the porous conductive material portion is a porous metal.
9. The semiconductor unit according to any one of 8. 11. A method of mounting a semiconductor element on a circuit board in a face-down state, wherein a terminal electrode of the semiconductor element and a connection electrode of the circuit board are electrically connected using a porous conductive material. By connecting, an electrode connection step of forming a porous conductive material portion, and after the electrode connection step, a resin filling step of filling a gap between the semiconductor element and the circuit board with a liquid sealing resin, Simultaneously with the resin filling step, an impregnating step of impregnating the porous space of the porous conductive material portion with the liquid sealing resin, and a resin curing step of curing the liquid sealing resin after the impregnating step And a method for mounting a semiconductor element. 12. A method of mounting a semiconductor element on a circuit board in a face-down state, wherein a terminal electrode of the semiconductor element and a connection electrode of the circuit board are connected to each other.
An electrode connection step of electrically connecting using a conductive adhesive, and after the electrode connection step, a curing of the conductive adhesive to form a conductive material portion forming a porous conductive material portion, After the conductive material portion forming step, a resin filling step of filling the gap between the semiconductor element and the circuit board with a liquid sealing resin, and simultaneously with the resin filling step, the liquid sealing resin is A method for mounting a semiconductor device, comprising: an impregnation step of impregnating a porous space of a porous conductive material portion; and a resin curing step of curing the liquid sealing resin after the impregnation step. 13. The method according to claim 12, wherein the conductive adhesive contains at least a solvent, an organic resin, and a conductive filler. 14. The method according to claim 13, wherein the liquid sealing resin has no solubility in the cured conductive adhesive. 15. The method according to claim 11, wherein the liquid sealing resin contains at least an organic resin and an inorganic filler. 16. The method according to claim 1, wherein in the impregnating step, the liquid sealing resin is impregnated into the porous space so as not to be impregnated with the inorganic filler.
6. The mounting method of the semiconductor element according to 5. 17. The semiconductor according to claim 15, wherein in the impregnating step, the liquid sealing resin is impregnated into the porous space so that the organic resin and the inorganic filler are impregnated. Element mounting method. 18. The method according to claim 18, further comprising: a step of forming a projecting electrode on the terminal electrode before the electrode connecting step. In the electrode connecting step, the terminal electrode and the connection electrode are connected to the projecting electrode. The method for mounting a semiconductor device according to claim 11, wherein the semiconductor device is electrically connected to the semiconductor device via a wire.