KR20040047532A - External electrode connector - Google Patents

Abstract

PURPOSE: An external electrode connector is provided to stabilize a current flow between external electrodes by preventing breakdowns of an interlayer dielectric of the external electrode. CONSTITUTION: An external electrode connector connects between external electrodes. The external electrode connector includes a first metal layer(2a), a first buffer layer(5a) and a second metal layer(2b). The first buffer layer is formed on the first metal layer and electrically coupled to the first metal layer. In the first buffer layer, conductors and elastic bodies are alternatively arranged or the conductors are arranged within a principal plane of the elastic body. The second metal layer is formed on the first buffer layer and is electrically coupled to the first buffer layer. The elastic body is lower in Young's modulus than the first metal layer, the conductor, and the second metal layer.

Description

External Electrode Connector {EXTERNAL ELECTRODE CONNECTOR}

The present invention relates to an external electrode connector for electrically connecting between external electrodes such as a substrate or a semiconductor element.

The conventional semiconductor device has a structure in which a semiconductor element and an anisotropic conductive film are integrally bonded to each other, and ends of the conductive paths of the film are bonded to each pad as an external electrode of the element and connected to the outside via the film. At this time, the anisotropic conductive film had a structure in which a plurality of conductive paths were provided as conductive paths in a state in which metal conductor wires were insulated from each other in a film substrate made of an insulating resin and penetrated the film substrate in the thickness direction (for example, a patent See Document 1).

[Patent Document 1]

Japanese Patent Laid-Open No. 2000-286293 (first page, Fig. 1)

In the conventional semiconductor device, since the electrical connection between the pad and the outside of the semiconductor device is made by the metallic conductive path provided in the thickness direction of the insulating film substrate, the conductive path and the pad of the anisotropic conductive film, There is a problem that the electrical bonding area of is small, resulting in poor conductivity between the pad and the outside of the semiconductor device. Even if the conductivity is not poor, the contact resistance between the pad and the conductive path or the conductive path and the external conductive path of the semiconductor device may increase, resulting in problems such as degradation of the transmission signal. On the other hand, it is possible to increase the conductivity between them by applying a load between the semiconductor device and the outside and increasing the contact pressure between the pad and the conduction path of the semiconductor device and the conduction path, but in this case, the semiconductor There was a problem that the interlayer insulating film, which is the underlying layer of the external electrode of the device, was broken.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to obtain an external electrode connector having a high conductivity, which is unlikely to cause breakage of the underlying layer of the external electrode due to the connection between the external electrodes.

Fig. 1A is a sectional view showing an external electrode connector in Embodiment 1 of the present invention, and Fig. 1B is a sectional view taken along the line I-I thereof.

2A is a plan view of a semiconductor device, FIG. 2B is a II-II cross-sectional view thereof, and FIG. 2C is an enlarged view of a cross section of a pad peripheral portion.

FIG. 3A is a view showing a state in which an external electrode connector is connected to a semiconductor element in Embodiment 1 of the present invention, and FIG. 3B is a view showing a state in which a semiconductor element to which the external electrode connector is connected is mounted on a mounting substrate. 3C is an enlarged view of the pad peripheral portion at the time of mounting.

FIG. 4A is a view showing a state in which semiconductor elements are connected by external electrode connectors in Embodiment 1 of the present invention, and FIG. 4B is an enlarged view of a pad peripheral portion at the time of mounting.

Fig. 5 is a diagram showing the manufacturing process of the external electrode connector in Example 1 of the present invention.

Fig. 6 is a view showing the manufacturing process of the external electrode connector in Example 1 of the present invention.

FIG. 7A is a cross-sectional view showing still another external electrode connector in Embodiment 1 of the present invention, and FIG. 7B is a cross-sectional view of III-III thereof.

Fig. 8A is a cross sectional view showing an external electrode connector and a pad peripheral portion according to the second embodiment of the present invention, and Fig. 8B is a sectional view taken along the line IV-IV and V-V of the external electrode connector.

Fig. 9A is a cross sectional view showing still another external electrode connector and a pad periphery according to the second embodiment of the present invention, and Fig. 9B is a sectional view taken along the line VI-VI and VII-VlI of the external electrode connector.

Fig. 10A is a cross sectional view showing a pad periphery of a semiconductor device according to the third embodiment of the present invention, Fig. 10B is an enlarged view of the pad, and Fig. 10C is a VIII-VIII cross-sectional view thereof.

Fig. 11A is a view showing a state in which a semiconductor device with pads is mounted on a mounting substrate in Embodiment 3 of the present invention, and Fig. 11B is a view showing a state in which these semiconductor devices are connected to each other.

Fig. 12 is a sectional view showing a pad peripheral portion of still another semiconductor device in accordance with the third embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

1: external electrode connector 2a: first metal layer

2b: second metal layer 2c: third metal layer

3a, 3b: conductors 4a, 4b: elastic bodies

5a: first buffer layer 5b: second buffer layer

6: semiconductor device 11: interlayer insulating film

13: Barrier Metal 16: Internal Metallization

17: pad surface 107: pad

The external electrode connector according to the present invention is formed on the first metal layer and the first metal layer and is electrically connected to the first metal layer, and the conductor and the elastic body alternately or the conductor is inside the main body of the elastic body. And a second metal layer formed on the first buffer layer and electrically connected to the first buffer layer, the Young's modulus of the elastic body being the first metal layer and the conductor, And a Young's modulus of the second metal layer.

EXAMPLE

Example 1

1A is a sectional view showing an external electrode connector according to Embodiment 1 of the present invention, and FIG. 1B is a sectional view taken along line I-I thereof. As shown in this figure, the external electrode connector 1 alternately arranges a first metal layer 2a such as gold, a conductor 3a such as gold, and an elastic body 4a such as polyimide or rubber. The first buffer layer 5a and the second metal layer 2b such as gold overlap with each other in this order. At this time, the first metal layer 2a and the conductor 3a, and the conductor 3a and the second metal layer 2b are in a conductive state. In addition, the Young's modulus of the elastic body 4a is smaller than the Young's modulus of the first metal layer 2a and the conductor 3a and the second metal layer 2b.

2A is a plan view of a semiconductor device, FIG. 2B is a II-II cross-sectional view thereof, and FIG. 2C is an enlarged view of a cross section of a pad peripheral portion. On the main surface of the semiconductor element 6, pads 7 made of aluminum or the like, which are external electrodes of the semiconductor element 6, are arranged in the form of a checker board, and are covered with a surface protective film 9 except for the pad opening 8. . In addition, as shown in FIG. 2B or 2C, the cross-section of the semiconductor device 6 has an interlayer insulating film 11, which is an external electrode underlayer, formed on the semiconductor substrate 10, and pads are formed on the interlayer insulating film 11. (7) is formed. At this time, although not shown, the pad 7 is electrically connected to an internal metal wiring formed on or in the interlayer insulating film 11 and an internal circuit connected thereto.

FIG. 3A is a view showing a state in which the external electrode connector is connected to a pad of a semiconductor device, and FIG. 3B is a view showing a state in which a semiconductor device to which the external electrode connector is connected is mounted on a mounting substrate, and FIG. Is an enlarged view of the pad periphery of the external electrode connector 1, in which a conductive adhesive (not shown) is applied to the connection surface, the first metal layer 2a of the external electrode connector 1 formed on the surface of the pad 7. Gold and the like are bonded to the barrier metal 13 made of titanium or the like to prevent diffusion of the pad 7 into aluminum or the like. The semiconductor element 6 and the mounting board 12 to which the external electrode connector 1 is attached are formed on the external electrode connector 1 and the mounting board 12 which are coated with a conductive adhesive (not shown) on the connection surface. After the substrate electrodes 14, which are external electrodes of the formed mounting substrate 12, are aligned, they are connected by applying a load from the vertical direction in the drawing.

FIG. 4A is a view showing a state in which semiconductor elements are connected to each other using this external electrode connector. FIG. 4B is an enlarged view of a pad peripheral portion at the time of connection. (Not shown) and the pad 7 of the two semiconductor elements 6 to be connected are aligned, and a load is applied from the up and down direction of the drawing. At this time, the barrier metal 13 is formed on the surface of the pad 7 of both semiconductor elements 6 in the same manner as in the case of mounting on the mounting substrate.

Next, the manufacturing method of the external electrode connector 1 is demonstrated with reference to FIG. FIG. 5A is a diagram of a pad periphery before forming the external electrode connector 1, showing only the pad 7, the surface protective film 9, and the interlayer insulating film 11. A barrier metal 13 is formed on the surface of the pad 7 by sputtering (FIG. 5B), and a layer of gold which is the first metal layer 2a is formed on the surface of the barrier metal 13 by sputtering (FIG. 5c) Next, a layer of polyimide that is an elastic body 4a is formed on the surface of the first metal layer 2a by spin coating (FIG. 5D), and then a conductor is formed on the elastic body 4a by photolithography. An opening 15 for forming (3a) is formed (FIG. 6A), and then the plating 15 is filled with gold as the conductor 3a by the plating (FIG. 6B), followed by sputtering. A layer of gold, which is the second metal layer 2b, is formed (FIG. 6C), and then the second metal layer 2b, the elastic body 4a, the first metal layer 2a, and the barrier metal 13 which are unnecessary by photo-printing and etching. Is removed (FIG. 6D). Here, the layer formed at the process of FIGS. 5D-6B is the 1st buffer layer 5a.

In this embodiment, the external electrode connector 1 is integrally formed on the semiconductor element 6, but the external electrode connector 1 has a concave portion or a prismatic shape instead of the pad peripheral portion of the semiconductor element 6. You may manufacture as a separate component on the basis of a metal mold | die, and join it to the barrier metal 13 of the semiconductor element 6 using a conductive adhesive agent (not shown). In addition, in the present embodiment, the barrier metal 13 is formed to prevent the material of the first metal layer 2a from diffusing into the pad 7, but the material of the first metal layer 2a and the pad 7 In the case where the materials are the same or when it is not necessary to consider the problem due to material diffusion, the barrier metal 13 may be omitted.

Next, the effect of the external electrode connector 1 will be described with reference to FIG. 3. When attaching the semiconductor element 6 with the external electrode connector 1 to the mounting substrate 12, a large load is applied in the vertical direction of FIG. 3C, but the elastic body 4a is left and right in FIG. 3C by this load. A part of the load received by deforming in the direction is dispersed in the left and right directions of FIG. 3C. For this reason, the load on the pad 7 and the interlayer insulating film 11 is reduced, and the interlayer insulating film 11 becomes hard to be broken. In addition, since the entire surface of the external electrode connector 1 bonded to the pad 7 or the substrate electrode 14 is made of metal, the pad 7 and the substrate electrode 14 can be stably conducted. In addition, also in the connection of the semiconductor elements 6 shown in FIG. 4, the same effect is acquired by the same principle. In this embodiment, since the area of the connection portion is small as the external electrode, it is difficult to catch the conductivity, and thus the effect of the external electrode connector is used by using a pad of a semiconductor device or a substrate electrode of a mounting substrate, which is likely to break an interlayer insulating film, which is a base layer of the external electrode. Although described, the scope of application of the external electrode connector of the present invention is not limited to these, and it can be used as an electrical connection component for the first half of an external electrode such as a liquid crystal plate and a flexible substrate.

In addition, although the conductor 3a and the elastic body 4a are alternately arranged in the 1st buffer layer 5a of Example 1, as shown in FIG. 7, the cylindrical conductor 3a is made into the elastic body 4a. It may be arranged in the form of a checkerboard inside the main surface.

In addition, the first metal layer 2a, the conductor 3a, and the elastic body 4a may each be made of a single material, or may be made of a plurality of materials such as an alloy or a mixture of polyimide and rubber. In addition, the 1st metal layer 2a, the conductor 3a, and the 2nd metal layer 2b may consist of the same material, or may consist of another material.

Example 2

8A is a cross-sectional view showing an external electrode connector and a pad peripheral portion according to Embodiment 2 of the present invention, and FIG. 8B is a IV-IV cross-sectional view and a V-V cross-sectional view of the external electrode connector 1. In this case, since the same reference numerals are given to the same or equivalent parts as those of the first embodiment shown in FIGS. 1 to 7, the description thereof is omitted. As shown in the figure, the external electrode connector 1 of the second embodiment uses the second buffer layer 5b on the second metal layer 2b and the third metal layer 2c on the second buffer layer 5b. The conductors 3b of the second buffer layer 5b and the conductors 3a of the first buffer layer 5a do not overlap each other in a direction perpendicular to the main surface of the second buffer layer 5b. The conductor 3b and the conductor 3a are arranged. When the loads when connecting the semiconductor elements or when the semiconductor elements are mounted on the mounting substrate are applied to the conductor 3b of the second buffer layer 5b, the load is mainly applied directly below the conductor 3b. In the case of the embodiment, since the elastic body 4a of the first buffer layer 5a is always located directly under the conductor 3b, the load is more easily distributed.

At this time, the first buffer layer 5a and the second buffer layer 5b of Example 2 alternately arrange the conductors 3a and 3b and the elastic bodies 4a and 4b, but as shown in FIG. You may arrange in the form of a checkerboard inside the main surface of elastic bodies 4a and 4b. In addition, the external electrode connector 1 of Example 2 forms a conductor up to the second metal layer 2b in the same process as the external electrode connector 1 of Example 1 shown in Figs. It can manufacture by repeating the process of FIGS. 5D-6D by changing the position which forms 3b into the position which does not overlap with the conductor 3a in the direction perpendicular | vertical to the main surface of the 2nd buffer layer 5b.

Example 3

Fig. 10A is a sectional view showing a pad periphery of a semiconductor device according to the third embodiment of the present invention, Fig. 10B is an enlarged view of the pad, and Fig. 10C is a VIII-VIII cross-sectional view thereof. At this time, since the same reference numerals are attached to the same or equivalent parts as those of the first embodiment shown in Figs. 1 to 7, the description thereof is omitted. The external electrode connector of the third embodiment forms a pad 107, wherein the first metal layer 2a is formed of an interlayer insulating film 11, an underlayer of the external electrode of the semiconductor element 6, an internal metal wiring 16, and the like. Is connected to a barrier metal 13 such as titanium formed on the surface), and the surface of the second metal layer 2b is the pad surface 17.

Fig. 11A is a view showing a state in which a semiconductor device having pads 107 of the third embodiment is mounted on a mounting substrate, and Fig. 11B is a view showing a state in which these semiconductor devices are connected to each other. As shown in FIG. 11A, the semiconductor element 6 including the pad 107 includes solder 18 coated with a conductive adhesive (not shown) on the connection surface between the pad 107 and the substrate electrode 14. ) Is mounted and mounted on the mounting substrate 12 by compressing by applying a load in the vertical direction of the figure. As shown in FIG. 11B, the pads 107 of the semiconductor element 6 are loaded between the pads 107 with a solder 18 coated with a conductive adhesive (not shown) on the connection surface. It joins by adding.

In the pad 107 of the semiconductor element 6 according to the third embodiment, since the pad 107 itself includes the elastic body 4a, the pads 107 of the semiconductor element 6 are connected to each other or the semiconductors. Since the elastic body 4a deforms the load which the pad 107 receives by mounting the element 6 to the mounting board 12 in the direction parallel to the pad surface 17, the interlayer insulating film 11 This damage can be reduced. The damage of the interlayer insulating film 11 is also caused by the contact of the probe needle (not shown) to the pad surface 17, which is a probe in the wafer test, but the pad of the semiconductor element 6 of the third embodiment. Since 107 has a structure in which the pad 107 itself distributes the load, the damage of the interlayer insulating film 11 in the wafer test can be reduced. In addition, since the pad 107 of the third embodiment is made of metal, both of the surface in contact with the internal metal wiring 16 and the surface in contact with the solder 18 and the probe needle are metal, so that the internal metal wiring 16 and the solder ( 18) and between the inner metal wiring 16 and the probe needle can be stably conducted. At this time, the pad structure can be manufactured by the same process as the manufacturing process of the external electrode connector shown in FIG. 5 and FIG. 6 using the existing semiconductor element manufacturing equipment.

At this time, in the semiconductor device 6 of the third embodiment, although the barrier metal 13 is formed between the internal metal wiring 16 and the first metal layer 2a, the internal metal wiring 16 and the first metal layer 2 are formed. ) Is the same material or when the material diffusion between them does not matter, the barrier metal 13 may be omitted. On the other hand, when the diffusion of the material between the first metal layer 2a and the conductor 3a becomes a problem, or when the diffusion of the material between the conductor 3a and the second metal layer 2b becomes a problem, If barrier metals 13 are formed between the first metal layer 2a and the first buffer layer 5a and between the first buffer layer 5a and the second metal layer 2b, respectively, material diffusion therebetween can be prevented. have.

In the semiconductor device 6 of the third embodiment, since the inner metal wiring 16 is formed inside the interlayer insulating film 11, the pad 107 is formed on both sides of the interlayer insulating film 11 and the inner metal wiring 16. 12, but when the inner metal wiring 16 is formed on the interlayer insulating film 11, the pad 107 is formed on the interlayer insulating film 11, and the inner metal is formed. The wiring 160 has a structure connected to the side surface of the first metal layer 2a.

Furthermore, similarly to the external electrode connectors of the second embodiment shown in FIGS. 8 and 9, the second buffer layer 5b is formed on the second metal layer 2b and the third metal layer 2c is formed on the second buffer layer 5b. In a direction perpendicular to the main surface of the second buffer layer 5b, the conductor 3b of the second buffer layer 5b and the conductor 3a of the first buffer layer 5a do not overlap each other. With the structure in which the sieve 3b and the conductor 3a are arranged, the damage to the interlayer insulating film 11 at the time of mounting is further reduced. In addition, although the pad 107 of Example 3 arrange | positions the conductor 3a and the elastic body 4a alternately, the external electrode connectors of Example 1 shown in FIG. 7 are columnar conductor 3a. May be arranged in the form of a checkerboard inside the main surface of the elastic body 4a. In addition, the first metal layer 2a, the conductor 3a, and the elastic body 4a may each be made of a single material, or may be made of a plurality of materials such as an alloy or a mixture of polyimide and rubber. In addition, the 1st metal layer 2a, the conductor 3a, and the 2nd metal layer 2b may consist of the same material, or may consist of another material. In addition, in the present embodiment, the external electrode connector is difficult to hold the conductivity because the area of the connection is small, and the interlayer insulating film 11 serving as the base layer of the external electrode is applied to a pad of a semiconductor device that is fragile. It may be applied to a substrate electrode or a liquid crystal pad.

As described above, the external electrode connector according to the present invention includes a first metal layer, a first buffer layer in which the conductor and the elastic body are alternately arranged, or the conductor is arranged inside the main body of the elastic body, and the second metal layer, and the Young's modulus of the elastic body Since it is smaller than the Young's modulus of a 1st metal layer, a conductor, and a 2nd metal layer, the crack of an underlayer of an external electrode by a connection between external electrodes is hard to occur. In addition, it is possible to stably conduct between external electrodes.

Claims (3)

In the external electrode connector for connecting between the external electrodes, A first buffer layer formed on the first metal layer and electrically connected to the first metal layer, the first buffer layer in which conductors and elastic bodies are alternately arranged, or the conductors are arranged inside the main surface of the elastic body; A second metal layer formed on the first buffer layer and electrically connected to the first buffer layer, wherein the Young's modulus of the elastic body is smaller than the Young's modulus of the first metal layer, the conductor, and the second metal layer. External electrode connector. The method of claim 1, A second buffer layer formed on the second metal layer and electrically connected to the second metal layer, and on which the conductor and the elastic body are alternately arranged or the conductors are arranged inside the main surface of the elastic body, and on the second buffer layer; And a third metal layer electrically connected to the second buffer layer, wherein the conductor of the first buffer layer and the conductor of the second buffer layer do not overlap each other in a direction perpendicular to the main surface of the second buffer layer. And the conductor of the first buffer layer and the conductor of the second buffer layer are arranged. The method according to claim 1 or 2, An external electrode connector, wherein the external electrode is an internal metal wiring of the semiconductor element, the internal metal wiring and the first metal layer are connected, and the surface of the second metal layer forms a pad surface.