JP2002009221A - Semiconductor device and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a die bonding material from short-circuiting between islands without increasing the size between the islands in a semiconductor device having a multi-chip configuration that the islands loading a circuit chip are separately provided. SOLUTION: A circuit chip is fixed by die bonding material on each of plural islands 11, 12. At least edges 11a, 12a of the opposing ends of the plural islands 11, 12 are formed to be higher on the side that a die bonding material 17 is arranged so as to hold the die bonding material that sticks out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device in which a plurality of circuit chips such as integrated circuit (IC) chips, diode chips, and capacitor chips are die-bonded in one package, and a method of manufacturing the same.

[0002]

2. Description of the Related Art A semiconductor device having a multi-chip structure in which a plurality of IC chips are die-bonded to one or a plurality of islands has been used.

FIG. 5 shows an example of a structure of a conventional multi-chip semiconductor device before packaging. In FIG. 5, an IC chip 53 and an IC chip 54 having different structures are mounted on islands 51 and 52 formed using a lead frame, respectively.
The IC chips 53 and 54 are fixed to the islands 51 and 52 by die bonding using a die bonding material such as a eutectic alloy of i or a conductive resin. Then, the inner lead 55 similarly formed using the lead frame is used.
And the pads of the IC chips 53 and 54 are connected to each other by wire bonding. 56 is a tablet suspension lead. In this state, through an assembly process such as general molding or packaging, 1
Semiconductor devices.

In such a multi-chip semiconductor device having a plurality of islands, it is necessary to separately set the islands 51 and 52 on which the IC chips 53 and 54 are mounted. To reduce the effect on the IC chip.

[0005]

[0006] However, as shown in FIG.
The die bonding material 57 is applied to the IC chips 1 and 52, and the IC chips 53 and 54 are mounted on the die bonding material. It may protrude more. Since the dimension between the islands 51 and 52 is often the minimum dimension that can maintain insulation in order to achieve high-density mounting, the protruding die bonding materials 57a and 57b may cause a short between the islands. There was a problem.

Accordingly, the present invention provides a multi-chip semiconductor device having a plurality of islands on which circuit chips such as an IC chip, a diode chip, and a capacitor chip are mounted, without significantly increasing the dimension between the islands. It is an object of the present invention to provide a semiconductor device capable of preventing a short circuit between islands due to a bonding material and a method of manufacturing the same.

[0007]

According to a first aspect of the present invention, there is provided a semiconductor device having a plurality of islands to each of which a circuit chip is fixed by a die bonding material. Are formed higher on the side where the die bonding material is used.

According to the semiconductor device of the first aspect, in a semiconductor device having a multi-chip configuration in which the plurality of circuit chips 13 and 14 are die-bonded to the plurality of islands, the circuit chips are short-circuited via the die bonding material. Can be prevented. Therefore, the number of defects generated during die bonding is reduced, and the yield is improved.

Further, since it is not necessary to increase the interval between the opposing islands, mounting can be performed at a high density.

A semiconductor device according to a second aspect of the present invention is the semiconductor device according to the first aspect, wherein an end of the island that is formed high is bent at an end of the island.

According to the semiconductor device of the second aspect, further,
No components are required other than a flat island.

According to a third aspect of the present invention, there is provided a method of manufacturing a semiconductor device in which a plurality of islands to which a circuit chip is fixed by a die bonding material are housed in one package. A gap portion 26 having a predetermined first width dimension d1 and being an interval between islands from the side
Is punched out with the other surface being supported at a distance d3 larger than the predetermined first width dimension, so that at least the ends 24 of the islands 24 and 25 face each other.
a, 25a forming the plurality of islands bent to the other surface side, a die bonding material is provided on the side where the ends of the plurality of islands are bent, and the circuit chip is die-bonded.

According to the semiconductor device manufacturing method of the third aspect of the present invention, since the metal thin plate 21 is punched from one surface side while being supported at the other surface at a distance d3 larger than the punching size, the island 24 is formed. , 25 opposite ends 24a,
25a is bent almost at the same time as the punching, and has a predetermined height h1.
Formed. As described above, since the bending of the end of the island can be performed in one step when the island is formed, the manufacturing is easy.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a semiconductor device having a plurality of islands to each of which a circuit chip is fixed by a die bonding material. A notch portion of d4 is formed, and the metal thin plate 31 is supported by the notch portion of the predetermined first width dimension d4 from the one surface side at an interval d6 larger than the predetermined first width dimension. Then, from the other surface side, a predetermined inclined surface and a member 35 having a second width dimension d5 (where the second width dimension d5> the first width dimension d4) are pressed so that at least the end portions of the islands 32, 33 are joined together. Opposite edge 32
a, 33a forming the plurality of bent islands, a die bonding material is provided on the side where the ends of the plurality of islands are bent, and the circuit chip is die-bonded.

According to a fourth aspect of the present invention, a notch having a predetermined first width d4 is formed in a thin metal plate, and a notch is formed on one side of the thin metal plate. Since the notch of the first width dimension d4 is pressed from the other surface side while being supported at the interval d6 larger than d4, the opposite ends 32a and 33a of the islands 32 and 33 are simultaneously bent, and the bending height is increased. The height h2 is more accurately formed at the predetermined height. As described above, since the bending of the end of the island can be performed simultaneously with the formation of the island, manufacturing is easy.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a semiconductor device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of a multichip semiconductor device according to the present invention. In FIG. 1, a first island 11 and a second island 12
Is formed of, for example, a lead frame made of copper or a copper alloy, and has a rectangular shape according to the shape of the mounted circuit chip as shown in FIG. Usually, the thickness of these islands 11 and 12 is several hundred μm (for example, 200 μm). These islands 11 and 12 are connected to a substrate potential of a circuit chip mounted thereon by reference potential Vss or Vs.
In order to reduce the influence of the temperature of one circuit chip on other circuit chips, they are separately formed so as to be connected separately to cc, for example.

These islands 11 and 12
Are end portions 11a and 12a of opposite sides facing each other.
However, it is bent upward as shown in the figure, and the height h of the bending is set in accordance with the conditions such as the viscosity and amount of the die bonding material 17, the weight of the circuit chip 13, and the pressing during mounting. You. For example, it is about 50 to 150 μm.

The first circuit chip 13 includes the first island 1
1 and fixed by die bonding using a die bonding material 17 such as solder or a eutectic alloy of Au-Si or a conductive resin. Similarly, the second circuit chip 1
No. 3 is mounted on the second island 12, and solder or A
It is fixed by die bonding using a die bonding material 17 such as a eutectic alloy of u-Si or a conductive resin.

The first island 11 has the circuit chip 1
The die bonding material 17 that has been added and applied in order to fix the circuit chip 3 is pressed when the circuit chip is mounted, the weight of the mounted circuit chip 13, the die bonding material 17.
Depending on the viscosity and amount conditions of the first island 11 and the first island 11
It protrudes from between the circuit chip 13.

However, the end 11a of the first island 11
However, the die bonding material 17 protruding from between the first island 11 and the first circuit chip 13 is bent upward by the height h as shown in FIG. It stays between the side of the first circuit chip 13 and forms a staying portion 17a. Similarly, since the end of the second island 12 is bent upward by a height h as shown in the figure, the die bonding material 17 protruding from between the second island 12 and the second circuit chip 14.
Stays between the end 12a of the second island 12 and the side of the second circuit chip 14 to form a stay 17b.

As described above, the protruding die bonding material 17 is applied to the end portions 11 of the first and second islands 11 and 12.
a, 12 a and the side portions of the first and second circuit chips 13, 14.
7 is prevented from overflowing beyond the bent ends 11a, 12a of the first and second islands 11,12. Further, the die bonding material 17 is formed by bending the end portions 11 a of the first and second islands 11 and 12,
Even when overflow occurs beyond 12a, the ends 11a and 12a of the first and second islands 11 and 12 are
Since there is a stagnation between the side portions of the second circuit chips 13 and 14, the amount of overflow is reduced.

Therefore, according to the present embodiment, the protruding die bonding material 17 makes it difficult for the first island 11 and the second island 12 to be short-circuited.

Further, since the space between the opposing islands 11 and 12 does not need to be greatly increased, high-density mounting can be achieved.

Although not shown, the first island 1
Similarly to the first and second islands 12, the inner leads formed by using a lead frame and the pads of the circuit chips 13 and 14 and the pads of the circuit chips 13 and 14 are connected to each other by wire bonding. The thickness of the circuit chip is at least about 100 μm or more, and usually about 300 to 400 μm or more.
Even if the ends of the islands 11 and 12 are bent upward by a height h (about 50 to 150 μm) as shown in FIG.
There is no obstacle to wiring between circuit chips.

In the above embodiment, the bending of the end of the island is performed on the sides facing each other. However, the present invention is not limited to this. The part can also be formed in a bent shape. In this case, the protruding die bonding material 17 does not go outside from the island, so that a short circuit to another lead or the like can be prevented.

Next, a method of manufacturing a semiconductor device according to the present invention will be described.

FIG. 2 is a diagram showing a first embodiment of the manufacturing method of the present invention. In FIG. 2, a lead frame 21 which is a thin metal plate has a thickness of several hundred μm (for example, 200 μm).
And formed of copper or a copper alloy. The punch 22 functions as an upper mold, and has a predetermined first shape.
Has a narrow width portion 22a having a width d1, a slope portion 22b, and a wide width portion 22c having a predetermined second width d2. The first width d1 of the narrow width 22a is made of metal. The dimensions correspond to the gap to be punched in the thin plate 21. Die 23
Functions as a lower mold, has a predetermined third width dimension d3, and is installed corresponding to the punch 22. The third width dimension d3 is the width of the narrow portion 22 of the punch 22.
The width is set to be larger than the width dimension d1 by a certain amount.
The width d2 of the large width portion 22c of the punch 22 is slightly larger than the third width d3 of the die 23 in the drawing, but may be smaller.

Now, as shown in FIG. 2A, the lead frame 21 is set at a predetermined position on the die 23, and the punch 22 is pushed down from above as shown by the arrow. First, in the first stage of the pressing down, the narrow portion 2 of the punch 22 is pressed.
Due to 2a, a gap 26 is punched out in the lead frame 21 with a first width dimension d1 and an interval between islands.

Subsequently, as shown in FIG. 3B, when the punch 22 is further pushed down, in the second stage of the pushing down, the inclined portion 22b following the wide portion 22a of the punch 22 has a width d1. Punched lead frame 21,
That is, the ends of the first island 24 and the second island 25 are pressed. In this state, the end 23a of the first island 24 and the end 25a of the second island 25 are each bent to have a predetermined height since the other surface side is supported by the die 23 with a predetermined width dimension d3. h1 (for example, about 50 to 150 μm). In this manner, the bending of the ends of the plurality of islands 24 and 25 can be performed in one step when the islands are formed.

Thereafter, the end 2 of each of the islands 24, 25
As shown in FIG. 1, a die bonding material is applied to the side where 4a and 25a are bent upward, and the circuit chip is die bonded.

Thus, according to the first manufacturing method, the metal thin plate 21 is punched out from one surface side while being supported on the other surface at an interval d3 larger than the punching size d1, and subsequently, the metal sheet 21 is formed on the slope portion. Press, Island 2
The opposing ends 24a, 25a of the 4, 25 are simultaneously bent to form a predetermined height h1. As described above, since the formation of the islands 24 and 25 and the bending of the ends 24a and 25a can be performed simultaneously and in one step, manufacturing is easy.

FIG. 3 is a view showing a second embodiment of the manufacturing method of the present invention. In FIG. 3, a lead frame 31 which is a thin metal plate is similar to the lead frame 21 of FIG. 2, and a gap having a first width dimension d4 is formed.
The punch 35 functions as an upper mold, and has a main body 35a having a predetermined second width dimension d5 and an inclined portion 35b at the tip thereof. The die 36 functions as a lower die, has a predetermined third width dimension d6, and is installed corresponding to the punch 35. The third width d6 is set to be larger by a certain amount than the first width d4 formed on the lead frame 31. Although the width d5 of the main body 35a of the punch 35 is slightly smaller than the third width d6 of the die 36 in the figure,
It may be large.

Next, a manufacturing procedure using this configuration will be described. First, as shown in FIGS. 7A and 7B, a gap portion 34 having a first width dimension d4 and an interval between the first island 32 and the second island 33 is provided at a predetermined position of the lead frame 31. Is formed. The gap 34 is
For example, it can be formed by an appropriate means such as forming by etching or punching out by pressing.

Next, as shown in FIG. 3C, the first island 32 and the second island 33 in which the gap 34 is formed with the first width dimension d4 are set at predetermined positions on the die 36. Then, the punch 35 is pushed down from above as shown by the arrow in the figure.

When the tip 35a of the punch 35 first enters the gap 34 between the islands and further pushes down the punch 35, the inclined portion 35b causes the width d4.
The first island 32 and the second island 33 formed by
Is pressed. In this state, since it is supported by the die 36 with a predetermined width dimension d6 from the other surface side,
As shown in FIG. 3D, the end 32a of the first island 32
The end 33a of the second island 33 is bent to have a predetermined height h2 (for example, about 50 to 150 μm). As described above, first, in the first stage, the gap portion 34 is formed on the lead frame 31 with the predetermined first width dimension d4, and then the end portions of the first and second islands 32, 33 on both sides of the gap portion 34 are formed. To the slope 35b of the punch 35
And the die 36, the end portions 32a, 33a
Is accurately formed at a predetermined height h2.

Thereafter, the end 3 of each of the islands 32, 33
A die bonding material is applied to the side where 2a and 33a are bent upward, and the circuit chip is die bonded as shown in FIG.

As described above, in the second manufacturing method, first,
A notch (gap) 34 having a predetermined first width d4 is formed in the metal thin plate 31, and a gap d6 larger than the notch d4 is formed on one surface of the metal thin plate on which the notch 34 is formed. While being supported by the holding die 36, the cutout portion 34 having the first width dimension d4, that is, the island 3
Since the ends of the islands 32 and 33 are pressed by the slope 35b of the punch 35, the opposite ends 32a and 33 of the islands 32 and 33 are pressed.
a is bent at the same time, and the bending height h2 is more accurately formed to a predetermined height. As described above, since the island end is bent after the island is formed, the structure of the upper die is simplified, the formation thereof is facilitated, and the cost of the die can be reduced.

In the first manufacturing method of FIG. 2 and the second manufacturing method of FIG. 3, the plurality of islands 24, 25 (3
Although the bending process is performed simultaneously with the formation of the islands on the opposite ends of (2, 33), the end portions of the other sides of each island can also be processed to be bent at the same time during the production thereof.

FIG. 4 is a diagram showing a configuration example of another island. In this figure, four islands 41 to 44 are formed. The present invention is not limited to two islands, but can be similarly applied to four islands as shown in this figure, or to islands of any other number and shape.

In the above embodiment, only the case where the end of the island is bent has been described. However, a convex wall may be separately formed at the end, or the wall may be formed by thinning the part other than the end of the island. It may be formed.

[0042]

According to the semiconductor device of the first aspect, in a semiconductor device having a multi-chip configuration in which a plurality of circuit chips are die-bonded to a plurality of islands, the circuit chips are short-circuited via the die bonding material. Can be prevented. Therefore, the number of defects generated during die bonding is reduced, and the yield is improved.

Further, since it is not necessary to increase the interval between the opposing islands, it is possible to mount the devices at a high density.

According to the semiconductor device of the second aspect, further,
No components are required other than a flat island.

According to the method of manufacturing a semiconductor device of the third aspect of the present invention, since the metal thin plate is punched from one side while being supported at intervals larger than the punching dimension on the other side, the islands are opposed to each other. The end is bent at substantially the same time as punching to form a predetermined height. As described above, since the bending of the end of the island can be performed in one step when the island is formed, the manufacturing is easy.

According to the method of manufacturing a semiconductor device of the fourth aspect of the present invention, a notch having a predetermined first width is formed in a thin metal plate, and the notch is formed on one side of the thin metal plate. Since the notch of the first width dimension is pressed from the other side while being supported at a large interval, the opposite ends of the island are simultaneously bent, and the bending height is more accurately adjusted to the predetermined height. It is formed. As described above, since the bending of the end of the island can be performed simultaneously with the formation of the island, manufacturing is easy.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an island of a semiconductor integrated circuit device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a first manufacturing method according to the embodiment of the present invention.

FIG. 3 is a view showing a second manufacturing method according to the embodiment of the present invention.

FIG. 4 is a diagram showing a configuration example of another island.

FIG. 5 illustrates a configuration example of a multichip semiconductor device.

FIG. 6 is a configuration diagram of an island of a conventional semiconductor integrated circuit device.

[Explanation of symbols]

 11, 24, 32 First island 12, 25, 33 Second island 11a, 24a, 32a Island end 12a, 25a, 33a Island end 13, 14, Circuit chip 17 Die bonding material 17a, 17b Staying part 21, 31 Lead Frame 22,35 punch 23,36 die

Claims (4)

[Claims] 1. A semiconductor device having a plurality of islands to which a circuit chip is fixed by a die bonding material, wherein at least ends of the plurality of islands where the ends of the islands face each other are formed higher on the side using the die bonding material. A semiconductor device characterized by being performed. 2. The semiconductor device according to claim 1, wherein an end of the island that is formed high is bent at an end of the island. 3. A method of manufacturing a semiconductor device in which a plurality of islands to which a circuit chip is fixed by a die bonding material are housed in one package, wherein the metal chip has a predetermined first width from one surface side on a thin metal plate. When punching a gap portion that is an interval between islands, the punching is performed in a state where the other surface side is supported at an interval larger than the predetermined first width dimension, and at least the end of the islands facing each other is opposite to the other surface side. Forming a plurality of islands that are bent in a curved line, providing a die bonding material on a side where the ends of the plurality of islands are bent, and die-bonding a circuit chip. 4. A method for manufacturing a semiconductor device having a plurality of islands to which a circuit chip is fixed by a die bonding material, wherein a notch having a predetermined first width is formed in a thin metal plate. In the notch of the predetermined first width dimension of the thin plate,
In a state of being supported from one surface side at an interval larger than the predetermined first width dimension, a predetermined inclined surface and a second width dimension (where the second width dimension> the first width dimension) are set from the other surface side. By pressing with a member having, at least the ends of the islands form the plurality of islands whose ends facing each other are bent, and a die bonding material is provided on the side where the ends of the plurality of islands are bent, and the circuit chip is mounted. A method for manufacturing a semiconductor device, comprising die bonding.