JP2924394B2 - Semiconductor device and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mounting a multichip module used in a workstation, a computer, or the like.

[0002]

2. Description of the Related Art In recent years, demands for miniaturization of workstations and computers have been increasing. In order to meet these demands, in the implementation of LSIs, multi-chip modules for directly mounting the LSIs have been actively developed.

Hereinafter, the above-mentioned multi-chip module will be described with reference to the drawings. FIG. 3 is a cross-sectional view of a conventional TAB package, and FIG. 4 is a cross-sectional view of a multi-chip module using the conventional TAB package. In FIG. 3 and FIG. 4, 1 is TAB
Packaged LSI chip, 2 is gold bump, 3 is T
AB package inner lead, 4 is a TAB package film, 5 is a TAB package outer lead, 6 is a TAB package protective resin, 7 is a circuit board,
8 is a circuit board field electrode, 9 is an external electrode of the circuit board, and 10 is an external lead of the multi-chip module.

The manufacturing method and structure configured as described above will be described. First, the TAB package shown in FIG. 3 will be described. TAB package is film 4
And a so-called film carrier comprising an inner lead 3 and an outer lead 5 supported by a film 4 and an LSI
It is composed of a chip 1. In this method of manufacturing a TAB package, first, the inner leads 3 of the film carrier and the gold bumps of the LSI chip 1 having the gold bumps 2 are aligned and matched. Inner lead 3
It is made of copper and its surface is plated with Sn, Au or the like. Next, the surface of the inner lead 3 is pressed by a heated pressing tool, the inner lead 3 is pressed against the gold bump 2, and the inner lead 3 and the gold bump 2 are joined together.
Next, a protective resin 6 is formed on the surface of the LSI chip 1 and TA
B package is obtained.

Next, a conventional multi-chip module using the TAB package will be described with reference to FIG. An electrode 8 of a circuit board 7 made of ceramic, silicon, or the like and having external leads 10 around the outer lead 5 of the TAB package is aligned, and the outer lead 5 and the electrode 8 are connected by soldering or the like. Hereinafter, a plurality of TAB packages are mounted on the circuit board 7 in a similar manner to obtain a multi-chip module.

LS mounted on multi-chip module
I is, for example, a microprocessor, a memory, or the like. As the performance of the device improves, high-speed transmission of signals between LSI chips is required.

[0007]

However, the above-described configuration has the following problems because the TAB packaged LSI chip is mounted on a circuit board in a planar manner. (1) The size of the module is large, and miniaturization cannot be achieved.

(2) High speed cannot be achieved because the distance between LSI chips is long. (3) Reliability is low because there are many connection points between LSI chips.

(4) The cost is high because the circuit board is very large. The present invention has been made in view of the above problems, and provides a small, high-speed, low-cost multi-chip module.

[0010]

Semiconductor device and manufacturing method thereof of the present invention to solve the above problems SUMMARY OF THE INVENTION are formed on flexible film having an opening, from the opening
A first lead group and a second lead group projecting at different lengths from each other.
At least one or more electrodes of the first semiconductor element are joined to the surface of the first lead group of the lead group of the lead group, and at least one or more second electrodes are attached to the back surface of the second lead group . the semiconductor device electrode of the semiconductor device is bonded
Wherein the electrode of the first semiconductor element is joined
The first lead group and the electrode of the second semiconductor element
2 and a part of the leads are connected on a flexible film
Is what it is.

[0011] Further, the opening is different from the opening.
A first lead group and a second lead group protruding with a certain length
Film carrier consisting of flexible film with
And a part of the first lead group and the second lead group.
Are connected on the flexible film
Carrier, the surface of the first lead group should have at least
Bonding the electrodes of one or more semiconductor elements;
At least one or more second halves are provided on the back surface of the second lead group.
Joining the electrodes of the conductive element.
It is a manufacturing method.

[0012]

[0013]

[0014]

[0015]

According to the present invention, a plurality of LSI chips are provided on the front and back of a lead projecting from an opening of a flexible film (a so-called inner lead of a film carrier of a TAB package). Connected in an overlapping manner as shown in FIG.
Since the leads connected to the I-chip are connected on a flexible film, a small, high-speed, low-cost multi-chip module can be obtained.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a multichip module according to one embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of a flexible film according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a multi-chip module of the present invention in each step. 1 and 2, 11 is a flexible film, 12 is a sprocket hole, 13 is an opening a, 14
Is an inner lead connected to the LSI chip 1, and 15 is
Inner leads to be connected to the LSI chip 2, 16 conductor wiring on a flexible film, 17 outer leads, 1
8 denotes an opening b, 19 denotes an LSI chip a, 20 denotes a protruding electrode, 21 denotes an LSI chip b, and 22 denotes a protruding electrode.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a so-called TAB package film carrier, and its configuration will be described. A flexible film 11 made of polyimide, polyester, or the like has a sprocket hole 1 for transportation.
2. It has an opening a for inserting an LSI chip and an opening b for supporting outer leads. The thickness of the flexible film 11 is about 50 μm to 125 μm. The opening a13 is formed larger than an LSI chip to be connected later. These are all formed by punching using a mold. Next, the conductor wiring will be described. On the flexible film 11, the conductor wiring 16, the inner leads 14, 15, and the outer leads 17 extending from the conductor wiring 16 are provided.
Are formed. These are formed by photoetching after bonding a copper foil to the flexible film 11.
The thickness of the conductor wiring 16 is about 18 μm to 35 μm. Inner leads 14 and 15 protruding from opening 13
Is a portion to be joined to an LSI chip having a different size later, and is formed at a position corresponding to an electrode of the LSI chip. The surface is plated with Sn, Au, or the like. The lead width of the inner leads 14 and 15 is usually 30
It is about μm to 100 μm. In addition, inner lead 1
A part of 4 and 15, for example, a power supply line and the like are integrated and electrically connected at a portion of the conductor wiring 16.

Next, a method for manufacturing a multi-chip module using this film carrier will be described with reference to FIG. First, as shown in FIG.
The protrusion electrode 20 of the LSI chip a19 having the above and the inner lead 14 are aligned. The projection electrode 20 is made of Au,
It is made of Cu or the like and has a thickness of 10 μm to 30 μm
m, the diameter is about 30 μm to 100 μm. Next, FIG.
As shown in FIG.
Pressurize and heat the inner lead 14 and the LSI chip a1.
Nine projecting electrodes 20 are joined together. The joining is performed with an Au-Sn alloy when the bump electrode 20 is made of Au and the surface of the inner lead 14 is made of Sn. In this case, a good connection can be obtained with a heating temperature of 300 ° C. to 400 ° C. and a pressure of about 10 to 50 grams per projection electrode. Next, as shown in FIG. 2C, the next LSI chip b21 to be bonded is arranged on the surface opposite to the LSI chip a19,
Protruding electrode 22 and inner lead 15 of SI chip b21
After positioning, the bonding tool 25
The inner leads 15 are heated one by one under pressure, and the inner leads 15 and the protruding electrodes 22 are joined. The bonding is Au-
This is performed by diffusion of Sn alloy or Au-Au. Further, ultrasonic vibration can be applied to the bonding tool 25. In that case, the bonding tool 25
Can be set lower, and is suitable for bonding of a device having low heat resistance. The bonding conditions are a heating temperature of 200 ° C. to 350 ° C. and a pressure of about 10 to 100 grams per projection electrode.
In addition, in bonding the protruding electrode of the LSI chip and the inner lead, the stage may be heated to heat the LSI chip. Next, as shown in FIG.
The flexible film 11 is cut at the portion 7 to obtain a multi-chip module. In this embodiment, the example in which the protruding electrodes are formed on the LSI chip side has been described. However, a method in which the protruding electrodes are formed on the inner lead side by a transfer bump method or the like may be used. In this case, the bonding method of the LSI chip can be easily performed by the same method as the case where the protruding electrode is formed on the LSI chip side. Also L
After the bonding of the SI chip is completed, the surface of the LSI chip can be protected using a resin. LSI chip a19
And part of the inner leads 14 and 15 connected to the LSI chip b21 are connected by the conductor wiring 16 as described above, and a circuit can be formed in this state. After connecting the LSI chip a19, performing a characteristic test and a burn-in test, the next LSI chip b is provided only in the region where the non-defective LSI chip a19 is connected.
By joining the two, the yield of the multi-chip module can be increased, and the cost can be reduced. This is a particularly effective means in the case of a CPU module in which the LSI chip a19 is a memory and the LSI chip b21 is a microprocessor, for example.

As described above, according to this embodiment, a plurality of LSI chips are connected to both sides of electrically independent inner leads of a film carrier, and some leads are connected on a flexible film. Thereby, a small, high-density, low-cost multi-chip module can be obtained. In addition, the following L is applied only to the non-defective LSI chip mounted first.
By mounting the SI chip, a multi-chip module with a very high yield can be obtained.

[0021]

As described above, according to the present invention, a plurality of LSI chips are connected to both sides of electrically independent inner leads of a film carrier, and some of the leads are connected to a flexible film. Since a multi-chip module is obtained on a film carrier, an LSI packaged in a TAB package on a
Unlike the method of mounting chips, it has a structure in which LSI chips are stacked, so that it can be made very small and high-density. In addition, the distance between the mounted LSI chips is very short, so that signal transmission does not occur. The speed is increased, and a high-speed multi-chip module can be obtained. In addition, by joining the next LSI chip only to a good LSI chip joined first, a very high yield and low cost multichip module can be obtained.

[Brief description of the drawings]

FIG. 1 is a top view of a film carrier according to a first embodiment of the present invention.

Step sectional views of an embodiment of a multi-chip module of the present invention; FIG

FIG. 3 is a cross-sectional view of a conventional TAB package.

FIG. 4 is a cross-sectional view of a conventional multi-chip module.

[Explanation of symbols]

 Reference Signs List 1 LSI chip packaged in TAB 2 Gold bump 3 Inner lead 4 Film 5 Outer lead 6 Protective resin 7 Circuit board 8 Electrode of circuit board 9 External electrode of circuit board 10 External lead 11 Flexible film 12 Sprocket hole 13 Opening A 14 Inner lead connected to LSI chip a 15 Inner lead connected to LSI chip b 16 Conductor wiring on flexible film 17 Outer lead 18 Opening B 19 LSI chip a 20 Projection electrode 21 LSI chip b 22 Projection electrode 23 Addition Pressure tool 24 Stage 25 Bonding tool

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) H01L 25/065 H01L 25/07 H01L 25/18

Claims (2)

(57) [Claims] 1. A formed on flexible film having an opening portion, the protruding in different length than the opening
Before the lead group consisting of the first lead group and the second lead group
At least one electrode of the first semiconductor element is joined to the front surface of the first lead group , and at least one electrode of the second semiconductor element is joined to the back surface of the second lead group. that a semi-conductor device, the first semiconductor element
A first lead group to which a semiconductor electrode is bonded and a second semiconductor element
A part of the second lead group to which the secondary electrode is joined is flexible
Semiconductor connected on conductive film
apparatus. 2. An opening, which is different from said opening.
It has a first lead group and a second lead group protruding in length.
Film carrier made of flexible film
A part of the first lead group and the second lead group
A film carrier connected on a flexible film
A, the surface of the first lead group has at least one
Bonding the electrodes of at least two semiconductor elements;
At least one second semiconductor on the back surface of the lead group
Bonding the electrodes of the device.
A method for manufacturing a semiconductor device.