JP2003092308A - Semiconductor device and method of manufacturing the same - Google Patents

Abstract

(57) [Summary] [PROBLEMS] A semiconductor device chip (CCD) using TAB technology
When joining the TAB tape to the solid-state imaging device chip), a stable joining state is obtained without causing any trouble such as breakage of bumps. SOLUTION: An electrode pad 1 of a CCD chip 110 in advance.
The bump 112 is fixed on the substrate 11, and the conductive adhesive 160 is provided thereon. Then, the bumps 112 of the CCD chip 110 are aligned with the inner lead portions 120 of the TAB tape, the heated tool 150 is brought into contact with the upper surface of the inner lead portions 120 of the TAB tape, and the conductive adhesive 160 is applied. Pressure and heat. Next, the sealing glass 140 coated with the sealing material 130 is positioned on the CCD chip 110, and is pressurized and heated to join the sealing glass 140 and the CCD chip 110.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a TAB (tape aut).
The present invention relates to a semiconductor device in which a lead portion of a TAB tape is bonded to a semiconductor element chip such as a solid-state image sensor by an omated bonding technique and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, when a CCD solid-state image pickup device chip (hereinafter referred to as a CCD chip) is packaged by using TAB technology, a stud bump method is generally used as a method for connecting a TAB tape and a CCD chip. ing. FIG. 3 is a cross-sectional view showing a configuration example of a solid-state imaging device packaged by a conventional stud bump method, and FIG. 4 is a main part showing a bump bonding operation in a bump transfer portion of the solid-state imaging device shown in FIG. It is an expanded sectional view. A light receiving portion (not shown) is provided in the center of the upper surface of the CCD chip 10, and an electrode pad 11 made of Al or the like is arranged around the light receiving portion. Then, usually, the bumps 12 such as Au stud bumps are fixed in advance on the electrode pads 11. The inner lead portion 20 of the TAB tape is formed by providing a large number of lead portions on the tape and extending each lead portion from the TAB tape.
The u-made lead is plated with Ni underlayer and Au.

The inner lead portion 20 of the TAB tape is positioned on the bump 12 as shown in FIG.
As shown in FIG. 5, pressure and ultrasonic waves are applied from the upper surface of the inner lead portion 20 of the TAB tape by the bonding tool 50, and the CCD chip 10 is heated from the rear surface side at 140 ° C. to 160 ° C. Thus, the bump 12 and the inner lead portion 20 of the TAB tape are joined (so-called single point bonding). Also,
As shown in FIG. 3, a sealing material 30 is filled and applied to the joint portion by such bumps 12, and a seal glass 40 is joined to the upper surface thereof. As a result, the light receiving portion of the CCD chip 10 is sealed in the package. The CCD chip 10 and the seal glass 40 are, for example, 2 to 5 mm
^It is formed as a rectangular plate with the same chip size having an area of about ² and the package size is the same as this chip size, making it an ultra-small package.

[0004]

However, in the above-mentioned conventional configuration, the electrode pad 11 and the inner lead portion 20 of the TAB tape are connected by the single point bonding by ultrasonic bonding or thermocompression of the Au bump 12. However, there is a problem that cracks are likely to occur under the Al electrode pad. Further, there is a problem that process instability is large because the management of bump hardness is complicated, the range of bond conditions is narrow, and the tool life is short. On the other hand, instead of providing the bumps on the electrode pad side as described above, it is possible to provide the bumps on the lead portion side of the TAB tape and bond them to the electrode pad side. In this case, the TAB tape with bumps is provided. However, there is a problem that the cost is high. From the viewpoint of the heat resistance of the CCD chip, it is preferable to control the heating temperature to 140 ° C. or lower. Therefore, the Au-made stud bumps and Cu-made Au / Ni-plated leads as described above are simply thermocompression bonded. Since it is necessary to perform the method at a high temperature (400 ° C or higher),
Not applicable to CD chips.

Therefore, an object of the present invention is to prevent the occurrence of cracks such as under-pad cracks when joining a lead portion of a TAB tape to a semiconductor element chip by the TAB technique.
It is an object of the present invention to provide a semiconductor device capable of obtaining a stable bonded state and a manufacturing method thereof.

[0006]

In order to achieve the above object, the present invention is directed to a semiconductor device in which an electrode pad of a semiconductor element chip and a lead portion of a TAB tape are connected via a bump, and the bump is previously formed on the semiconductor element chip. The electrode pad and the lead portion of the TAB tape are bonded to each other with the conductive adhesive interposed between the bump and the lead portion. Further, the present invention relates to a method of manufacturing a semiconductor device in which an electrode pad of a semiconductor element chip and a lead portion of a TAB tape are connected to each other. The bump and the lead portion are joined by aligning and abutting the portion with a paste-like conductive adhesive interposed therebetween and then curing the conductive adhesive.

In the semiconductor device according to the present invention, the bumps and the TAB that are previously fixed on the electrode pads of the semiconductor element chip are formed.
Since the electrode pad and the TAB tape are connected with the conductive adhesive interposed between the lead portions of the tape, the bumps and the lead portions can be joined by curing the conductive adhesive. Therefore, since there is no need to thermocompression-bond the bump and the lead portion as in the conventional case, it is possible to easily obtain a stable joined state without causing an underpad crack or the like, and to provide a highly reliable semiconductor device. Can be provided.

In the method of manufacturing a semiconductor device according to the present invention,
Since the bump and the lead portion are joined by curing the conductive adhesive in the state where the conductive adhesive is interposed between the bump that is previously fixed on the electrode pad of the semiconductor element chip and the lead portion of the TAB tape, As described above, the electrode pad and the TAB tape can be connected without thermocompression bonding the bump and the lead portion. Therefore, the manufacturing process can be simplified without causing troubles such as under-pad cracks and without complicated bump hardness management and bond condition control.
It is possible to reduce the burden on the tool, obtain a stable connection state between the semiconductor element chip and the TAB tape while reducing the cost due to the long life, and it is possible to manufacture a highly reliable semiconductor device at low cost.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a semiconductor device according to the present invention will be described below. The embodiments described below are preferred specific examples of the present invention, and various technically preferable limitations are given. However, the scope of the present invention is not limited to the present invention in the following description. Unless otherwise stated, the present invention is not limited to these embodiments. In this embodiment, the present invention is applied to a solid-state imaging device and a method for manufacturing the same, and a CCD chip is used as a TAB.
A configuration and a method for forming a chip size package by using a technique will be described.

FIG. 1 is an enlarged cross-sectional view of an essential part showing a structure of a connecting portion between a TAB tape and a CCD chip of a solid-state image pickup device according to this embodiment. FIG. 2 is an enlarged cross-sectional view of an essential part showing the work of connecting the TAB tape and the CCD chip of the solid-state imaging device shown in FIG. In the solid-state imaging device of this example, the entire configuration except the connection portion between the TAB tape and the CCD chip is the same as that of the conventional example shown in FIG. In the solid-state imaging device of this example, the CCD chip 11
The bump 112 is fixed in advance on the electrode pad 111 of 0, which is similar to the above-mentioned conventional example. However, in this example, a paste-like conductive adhesive 160 is provided on the bump 112, and The adhesive 160 is heated and pressed by the bonding tool 150 from above the inner lead portion 120 of the TAB tape, and the lead portion 120 of the TAB tape and the electrode pad 111 are bumped 112 and electrically conductive by the compressive deformation and curing of the conductive adhesive 160. The adhesive is bonded via the adhesive 160.

The individual components will be specifically described below. The CCD chip 110 is provided with a light receiving portion (not shown) at the center of the upper surface, and an electrode pad 111 made of Al or the like is arranged around the light receiving portion. This CCD chip 1
10 has an area of ² to 5 mm ² and a thickness of 0.2, for example.
It is formed in a rectangular plate shape having a chip size of ~ 0.7 mm. On the other hand, the seal glass 140 is formed in a rectangular shape having the same chip size as the CCD chip 110,
The package size is the same as the chip sizes of the CCD chip 110 and the seal glass 140, resulting in an ultra-small package.

The bump 112 is, for example, an Au stud bump, and the electrode pad 1 is formed by a stud bump bonder.
It is pre-fixed on 11. Each bump 1
The heights of the bumps 12 are made uniform by leveling as necessary, the diameter of each bump is 50 to 100 μm, and the wall thickness is 10.
It is about 20 μm. Further, as the conductive adhesive 160, for example, an adhesive paste containing Ag is used and is applied by transfer onto the upper surface of each bump 112. The inner lead portion 120 of the TAB tape is formed by providing a large number of lead portions on the tape and extending the tip of each lead portion from the TAB tape. For example, Cu lead is plated with Ni underlayer and Au. It was done. The width of the lead portion 120 is, for example, 50 to 100 μm.
m, and the thickness is 15 to 40 μm. In addition, in this example, the conductive adhesive 160 is applied to the bumps 112 in advance.
However, it may be provided on the TAB tape side. For example, the conductive adhesive 16 is formed on each inner lead portion 120 of the TAB tape by screen printing or dispense transfer.
0 can be provided. Further, the sealing material 130 is a semi-cured and thermosetting material, and the sealing glass 1
It is applied in a frame shape along the outer periphery of the lower surface of 40.

Next, C in such a solid-state image pickup device
Inner lead portion 12 of CD chip 110 and TAB tape
The joining work with 0 will be described. First, as shown in FIG. 2A, the electrode pads 11 of the CCD chip 110 are previously prepared.
1. Bump 112 is fixed on top of which conductive adhesive 1
60 is provided. Then, the bump 1 of the CCD chip 110
12 and the inner lead portion 120 of the TAB tape are aligned, and the heated tool 150 is attached to the inner lead portion 1.
The conductive adhesive 160 is pressed against the upper surface of 20 and heated. The heating in this case is, for example, 120 to 160 °.
C, about 30 seconds to 5 minutes, pressurization is, for example, 5 to 200 g
/ About bumps. Next, the seal glass 140 coated with the seal material 130 is aligned with the CCD chip 110 and pressed and heated to bond the seal glass 140 and the CCD chip 110. The heating in this case is, for example, 100
To about 160 ° C., and pressurization is 100 to 1000, for example.
It is about g.

By the bump bonding method for the solid-state image pickup device as described above, the following effects can be obtained. (1) It is possible to prevent cracks in the lower part of the electrode pad 111 at the time of connection, and it is possible to obtain high reliability. (2) The process can be stabilized. That is, it is not necessary to manage bump hardness, the tool life can be extended, and the range of process conditions (bond load, temperature) can be expanded. (3) The material cost can be reduced. (4) Since the connection can be performed at a low temperature, damage to the device can be reduced.

In the above example, the case where the present invention is applied to the CCD solid-state image pickup device has been described, but the present invention can be similarly applied to other semiconductor devices.
Further, it goes without saying that the materials and the respective numerical values described above can be appropriately changed.

[0016]

As described above, in the semiconductor device of the present invention, the conductive adhesive is interposed between the bumps that are previously fixed on the electrode pads of the semiconductor element chip and the lead portions of the TAB tape. The bumps and leads can be connected by curing the adhesive. Therefore, since there is no need to thermocompression-bond the bump and the lead portion as in the conventional case, it is possible to easily obtain a stable joined state without causing an underpad crack or the like, and to provide a highly reliable semiconductor device. Can be provided.

Further, in the method of manufacturing a semiconductor device according to the present invention, conductive bonding is performed with a conductive adhesive interposed between the bumps that are previously fixed on the electrode pads of the semiconductor element chip and the lead portions of the TAB tape. Since the bumps and the lead portions are joined by curing the agent, the bumps and the lead portions are not thermocompression bonded as in the conventional case, and the electrode pad and the TAB are
Tapes can be connected. Therefore, without causing troubles such as pad cracks, without complicated bump hardness management and bond condition control, the manufacturing process can be simplified, the load on the tool can be reduced, and the cost can be reduced by extending the life. At the same time, a stable connection between the semiconductor element chip and the TAB tape can be obtained, and a low-cost and highly reliable semiconductor device can be manufactured.

[Brief description of drawings]

FIG. 1 is a TA of a solid-state imaging device according to an embodiment of the present invention.
It is a principal part expanded sectional view which shows the structure of the junction part of B tape and CCD chip.

FIG. 2 is a TAB tape and CC of the solid-state imaging device shown in FIG.
It is a principal part expanded sectional view which shows the joining operation of a D chip.

FIG. 3 is a cross-sectional view showing a configuration example of a solid-state imaging device packaged by a conventional transfer bump method.

FIG. 4 is an enlarged sectional view of an essential part showing a bump joining operation in a bump transfer portion of the solid-state imaging device shown in FIG.

[Explanation of symbols]

110 ... CCD chip, 111 ... Electrode pad, 11
2 ... Bump, 120 ... TAB tape inner lead part, 130 ... Seal material, 140 ... Seal glass, 1
50 ... Bonding tool, 160 ... Conductive adhesive.

Claims (8)

[Claims] 1. A semiconductor device chip electrode pad and TAB
In a semiconductor device in which a lead portion of a tape is connected via a bump, the bump is fixed in advance on an electrode pad of a semiconductor element chip, and the electrode pad and the lead portion of the TAB tape are provided between the bump and the lead portion. A semiconductor device, wherein the semiconductor device is bonded with a conductive adhesive interposed. 2. The semiconductor device according to claim 1, wherein the semiconductor element chip is a CCD solid-state image pickup element chip. 3. A transparent cover for covering the light receiving portion on the upper surface of the CCD solid-state imaging device chip, wherein a light-receiving portion is provided on the upper surface of the CCD solid-state imaging device chip, and the electrode pad is arranged on the outer periphery of the light-receiving portion. 3. The semiconductor device according to claim 2, wherein the are bonded together via a sealing material. 4. An electrode pad of a semiconductor device chip and a TAB
In a method of manufacturing a semiconductor device in which a lead portion of a tape is connected, a bump is fixed in advance on an electrode pad of the semiconductor element chip, and the bump and the lead portion of the TAB tape are interposed with a paste-like conductive adhesive. The method for manufacturing a semiconductor device is characterized in that the bump and the lead portion are joined by curing the conductive adhesive after aligning and abutting in the above state. 5. The method of manufacturing a semiconductor device according to claim 4, wherein the conductive adhesive is provided on the bump side in advance. 6. The method of manufacturing a semiconductor device according to claim 4, wherein the conductive adhesive is provided in advance on the lead portion side of the TAB tape. 7. The method of manufacturing a semiconductor device according to claim 4, wherein the conductive adhesive is cured by pressurization and heating. 8. The method of manufacturing a semiconductor device according to claim 4, wherein the semiconductor element chip is a CCD solid-state imaging element chip.