JPH05109976A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent displacement of a semiconductor chip at the time of resin molding by connecting two semiconductor chips with rear faces closely adhering to each other to an outer lead by tape leads, attaching a first fixing member to a surface of one of the semiconductor chips and attaching a second fixing member to a surface of the other semiconductor chip. CONSTITUTION:Semiconductor chips 3A, 3B are connected to an outer lead 6a by tape leads 5A, 5B. A first fixing member 20A is fixed to a surface of the semiconductor chip 3A by adhesive 21 as well as a second fixing member 22A is fixed to a surface of the semiconductor chip 3B by the adhesive 21. Therefore, when this assembly is set in a metal mold and is subjected to resin molding, even if force is applied to the semiconductor chips 3A, 3B due to injection pressure of mold resin 7, the first fixing member 20A regulates a distance from an upper metal mold while the second fixing member 22A regulates a distance from a lower metal mold. Thus, a tape lead can be prevented from appearing on a package surface, thereby preventing electric snort-circuiting with outside at the time of packaging.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device having a plurality of semiconductor chips.

[0002] In recent years, there has been a chip-on-chip structure in which a plurality of semiconductor chips are mounted in one package while the density of ICs has been increased along with the miniaturization of electronic devices and the like. On the other hand, thinning of the package is required due to the lightness and miniaturization of the IC. Therefore, it is necessary to perform resin molding without displacing the semiconductor chip mounted inside the package.

[0003]

2. Description of the Related Art FIG. 6 is a block diagram of a conventional semiconductor device. 6, in the semiconductor device 1 _A having a plurality of semiconductor chips, the first and second semiconductor chips 3 _A and 3 _B are located in the central opening portion of the lead frame 2. This first
The second semiconductor chips 3 _A and 3 _B are in a state where their back surfaces are in close contact with each other (an adhesive or a molding resin may be interposed).

Further, the first and second semiconductor chips 3 _A ,
Bumps 4 are provided on both surfaces of 3 _B , and are connected (inner lead bonding) to one end of the tape leads 5 _A and 5 _B which are bent. The other ends of the tape leads 5 _A and 5 _B are thermocompression-bonded (outer lead bonding) to the outer leads 6 _a of the lead frame 2 and packaged with the molding resin 7. For example, for surface mounting, the outer leads 6 _a or L-shaped (J-shaped is also possible) processed.

Here, FIG. 7 is a view for explaining the manufacturing of FIG. As shown in FIG. 7A, the above-described semiconductor device 1 _A includes a lead frame 2 and semiconductor chips 3 _A , 3 _A.
After connecting the _B to the tape lead 5 _A, 5 _B, the semiconductor chip 3 _A, 3 _B peripheral portion of the upper die 8 _a and the lower mold 8 _b
It is set in the cavity 9 formed by. Then, the mold resin 7 is sealed from the gate 10 to perform molding.

In this case, the semiconductor chip 3_A, 3_BIs
Preed 5_A, 5_BOuter lead 6_aSupported by
The semiconductor chip is only
Three_A, 3 _BIs easily displaced. Therefore, the semiconductor chip 3_A，
Three_BPosition and injection speed of mold resin 7
Mold resin 7 from gate 10 is the semiconductor chip
Three _A, 3_BThe pressure to displace the
To prevent.

Next, FIG. 8 shows a block diagram of a conventional semiconductor device. 8, in the semiconductor device 1 _B , the semiconductor chips 11 _A and 11 _B having the bumps 4 on the front surface are closely attached to each other on the back surfaces, and the semiconductor chips 11 _C and 11 _D having the bumps 4 on the front surface are mutually _adjacent to each other. The back side is closely attached.

On the other hand, the outer lead 6 of the lead frame 2
_The other ends of the tape leads 12 _A and 12 _B and the bent tape leads 13 _A and 13 _B are thermocompression bonded on both surfaces of _b , and one ends thereof are connected to the semiconductor chips 11 _{A to} 11 _D. Then, it is packaged with the mold resin 7. In this case, the packaging is performed by a method similar to that shown in FIG. Also, for surface mounting, for example,
Outer leads 6 _b is processed in J shape.

[0009]

By the way, FIG. 7 (A)
As shown in, the semiconductor chip is filled at the initial stage of injection of the mold resin 7.
Up 3_A, 3_B(11_A~ 11_C) Has no displacement. Only
However, when the molding resin 7 is injected to some extent, the tape
Card 5_A, 5_B(12_A, 12_B, 13_A, 13 _B)of
Variations in manufacturing accuracy and injection speed of mold resin 7
Fig. 7 (B)
As shown in, the injection pressure causes the semiconductor chip 3_A, 3_B(11
_A~ 11_D) Is displaced. That is, this makes the tape
Lead 5_A, 5_B(13_A, 13_B) Is on the package
Display it to prevent an electrical short from the outside when mounting on the board.
There is a problem of causing it.

Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a semiconductor device which prevents displacement of a semiconductor chip during resin molding.

[0011]

SUMMARY OF THE INVENTION In the semiconductor device in which two semiconductor chips having their back surfaces adhered to each other and outer leads are connected by tape leads and then resin molding is performed, the above-mentioned two semiconductor chips are at least 1. In order to fix the position of the semiconductor chip at the time of resin molding, a first fixing member is attached to the surface of the semiconductor chip located at one end and at the surface of the semiconductor chip located at the other end. It is solved by attaching the second fixing member.

[0012]

As described above, the first fixing member is attached to the surface of the semiconductor chip located at one end, and the second fixing member is attached to the surface of the semiconductor chip located at the other end.

Thus, when the resin is set in the mold and the resin is molded, the first fixing member regulates the distance from the upper mold even if the semiconductor chip receives a force by the injection pressure of the mold resin. The second fixing member regulates the distance of the lower mold.

That is, it is possible to prevent the tape lead from being exposed on the package surface by the first and second fixing members. This makes it possible to prevent an electrical short circuit with the outside during mounting.

[0015]

FIG. 1 is a block diagram of the first embodiment of the present invention. In addition, hereinafter, the same components as those in FIGS. 6 and 8 are denoted by the same reference numerals. In FIG. 1, in the semiconductor device 1 _C , the back surfaces of the first and second semiconductor chips 3 _A and 3 _B having the bumps 4 are adhered to the central opening of the lead frame 2 (adhesive may be interposed). ) Let it be located. Then, the other ends of the tape leads 5 _A and 5 _B , which have been bent, are fixed to both surfaces of the outer leads 6 _a of the lead frame 2 by thermocompression bonding, and one ends thereof are connected to the semiconductor chips 3 _A and 3 _B and the bumps 4.
Connected via.

On the surface of the semiconductor chip 3 _A located at one end and inside the bump 4 connected to the tape lead 5 _A , a block-shaped first fixing member made of a polymer material such as epoxy resin is used. The member 20 _A is fixed by an insulating polymer adhesive 21 such as silicone resin.

On the other hand, the bump 4 connected to the tape lead 5 _{B on} the surface of the semiconductor chip 3 _B located at the other end.
_A second fixing member 22 _A made of the same material as that of the first fixing member is fixed to the inner side of the inside by an adhesive 21 made of the same material.

Then, it is molded with the molding resin 7. In this case, in FIG. 1, the first and second fixing members 2
The surfaces of 0 _A and 22 _A are exposed on the same surface as the package. In addition, the first and second fixing members 20 _A , 22
_The adhesive 21 for fixing _A is an insulating material as described above, and does not cause an electrical short even if it is exposed on the package surface.

After resin molding, the lead frame 2
The outer lead 6 _a is bent in the L-shaped for surface mounting.
Although all the leads for surface mounting are shown in the present embodiment and the following, the same applies to leads for insertion without being bent into an L shape.

Here, FIG. 2 is a view for explaining the manufacturing of FIG. In FIG. 2, first, the semiconductor chip 3 _A ,
After connecting 3 _B and the outer lead 6 _a with tape leads 5 _A and 5 _B , an adhesive 21 is applied to the surface of the semiconductor chip 3 _A.
The first fixing member 20 _A is fixed by the second fixing member 2 A with the adhesive 21 on the surface of the semiconductor chip 3 _B.
Fix 2 _A.

[0021] Therefore, in Kyabidi 9 of the lower mold 8 _b,
The second fixing member 22 _A is placed with the mold portions around the semiconductor chips 3 _A and 3 _B positioned. Also, the upper die 8
By covering _a , the first fixing portion 20 _A is moved to the upper mold 8
It comes into contact with _a. That is, the upper mold in Kyabidi within 9 8 _a
And the pressure when sandwiched by the lower mold 8 _b is relaxed by the deformation of the first and second fixing members 20 _A and 21 _A and the adhesive 21, and the pressure applied to the semiconductor chips 3 _A and 3 _B. Is fixed while reducing and protecting.

Then, resin molding is performed by encapsulating the molding resin 7 from the gate 10. In this case, since the semiconductor chips 3 _A and 3 _B are fixed, there is no need to control the injection speed and pressure, and the molding time can be shortened.

Thus, the first and second fixing members 20
_{By A} and 22 _A , the semiconductor chip 4 can be thinned without being displaced during resin molding, and the tape leads 5 _A and 5 _B are not exposed on the package surface. It is possible to prevent the occurrence of an electrical short circuit during mounting.

In the above embodiment, the case where the first and second fixing members 20 _A and 22 _A are exposed on the package surface is shown, but it is not always necessary to expose them and the semiconductor chip 3 is molded at the time of resin molding. _{To the} extent that the tape leads 5 _A and 5 _B do not appear on the package surface due to the displacement of _A and 3 _B ,
The thickness of the first and second fixing members 20 _A, 22 _A may be set.

Next, FIG. 3 shows a block diagram of another embodiment of FIG. The semiconductor device 1 _D shown in FIG. 3 has a second fixing member 2
The 0 _B, for example, heat dissipation good material such as aluminum is formed on the section opposite convex, in which so as to expose one side of entire surface of the package. Similarly, the second fixing member 22
_{Also in B} , a material with good heat dissipation is used so that it is exposed on the entire other surface of the package.

As a result, the heat generated when the semiconductor chips 3 _A and 3 _B are driven can be efficiently dissipated. In addition, in order to obtain more efficient heat dissipation, the first and second exposed
A slit may be formed on the surface of the fixing members 20 _B and 22 _B to increase the surface area.

Manufacturing of the semiconductor device 1 _D in FIG. 3 is similar to that in FIG. Next, FIG. 4 shows a block diagram of a second embodiment of the present invention. Semiconductor device 1 of FIG.
_E is provided with two semiconductor chips having their back surfaces adhered to each other in two stages as described above. In FIG. 4, in the semiconductor device 1 _E , the other ends of the tape lead 12 _A and the bent tape lead 13 _A are fixed on one surface of the outer lead 6 _b of the lead frame 2 by thermocompression bonding. The other end of the tape leads 12 _B and legs bent tape lead 13 _B is fixed by thermocompression bonding on the other surface.

Two sets of semiconductor chips 11 _A , 11 _A having bumps 4 at one end of each of the tape leads 12 _A , 13 _A and the tape leads 12 _B , 13 _B and having their back surfaces brought into close contact with each other are provided.
_B, 11 _C and 11 _D are connected in two stages via the bump 4.

On the surface of the semiconductor chip 11 _A located at one end and inside the bump 4, the first fixing member 20 _A of the same material as described above is fixed via the adhesive 21. Also,
_A second fixing member 22 _A made of the same material as described above is fixed to the inside of the bump 4 on the surface of the semiconductor chip 11 _D located at the other end via an adhesive 21. And between each stage,
The third fixing member 23 is fixed to the semiconductor chips 11 _B and 11 _C via the insulating adhesives 21 and 21 described above, respectively. Then, the molding resin 7 is used for packaging. Also, outer leads 6 _b is formed in a J shape as a surface mounting.

Such a semiconductor device 1 _E uses four semiconductor chips 11 _{A to} 11 _D in two stages.
Can be made thinner without expose the tape lead 13 _A, 13 _B similar to FIG. 1 by the through third fixing member 20 _A ~22 _A, 23. Next, FIG. 5 shows a block diagram of another embodiment of FIG. In the semiconductor device 1 _F of FIG. 5, the first and second fixing members 20 _A and 22 _A of FIG. 4 are made of a metal such as aluminum having good heat dissipation and formed in a reverse convex shape in cross section to be exposed on both surfaces of the package. It was made to let.
In this case, the adhesive 21 is interposed in order to prevent a short circuit between the first and second fixing members 20 _B and 22 _B and the tape leads 13 _A and 13 _B.

As a result, the heat generated by the semiconductor chips 11 _{A to} 11 _D can be efficiently dissipated. Also, as described above, in order to obtain more efficient heat dissipation, the first
Also, slits may be formed on the surfaces of the second fixing members 20 _B and 22 _B to increase the surface area.

[0032]

As described above, according to the present invention, at least one stage of two semiconductor chips whose back surfaces are adhered to each other is provided, and the first and second fixing members are provided on the front surfaces of the semiconductor chips located at one end and the other end, respectively. By attaching the semiconductor chip, it is possible to prevent the semiconductor chip from being displaced at the time of resin molding and to prevent the tape lead from being exposed, so that the performance of the thin semiconductor device can be improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a diagram for explaining the manufacturing of FIG.

FIG. 3 is a configuration diagram of another embodiment of FIG.

FIG. 4 is a configuration diagram of a second embodiment of the present invention.

5 is a configuration diagram of another embodiment of FIG. 4. FIG.

FIG. 6 is a configuration diagram of a conventional semiconductor device.

FIG. 7 is a diagram for explaining the manufacture of FIG. 6;

FIG. 8 is a configuration diagram of another conventional semiconductor device.

[Explanation of symbols]

1 _A to 1 _F semiconductor device 2 lead frame 3 _A , 3 _B , 11 _{A to} 11 _D semiconductor chip 4 bumps 5 _A , 5 _B , 13 _A , 13 _B tape lead 6 _a , 6 _b outer lead 7 mold resin 20 _A , 20 _B 1st fixing member 21 Adhesive 22 _A , 22 _B 2nd fixing member 23 3rd fixing member

Claims (4)

[Claims] 1. Two semiconductor chips whose back surfaces are closely attached
(3_A, 3_B, 11_A~ 11_D) And outer lead
(6_a, 6_b) And tape lead (5_A, 5_B, 1
Two _A, 12_B, 13_A, 13_B) After connecting by
In a semiconductor device for performing oil molding, the two semiconductor chips (3_A, 3_B, 11_A~ 1
1_D) Is provided in at least one stage, and the semiconductor chip (3_A, 3_B, 11_A~ 11_D) Above
This is located at one end to fix the position during resin molding.
Semiconductor chip (3_A, 11_A) The first fixing member on the surface of
(20_A) Is attached to the semiconductor chip (3_B, 11_D) Surface
The second fixing member (22_A) Is attached
Semiconductor device. 2. The at least one of the first fixing member (20 _B ) and the second fixing member (22 _B ) is formed in a reverse convex cross-section.
The semiconductor device described. 3. The two semiconductor chips (11 _A to 11 _{A)
When a} plurality of stages _D ) are provided, the two semiconductor chips (1
The semiconductor device according to claim 1 or 2, wherein a third fixing member (23) is attached between each step of 1 _{A to} 11 _D ). 4. The semiconductor according to claim 1, wherein the first fixing member (20 _B ) and the second fixing member (22 _B ) are formed of a metal having a good heat dissipation characteristic. apparatus.