JP2000003976A - Semiconductor device - Google Patents

Abstract

(57) Abstract: The present invention relates to a semiconductor device in which bonding electrodes (bumps) are arranged in an area array, and breakage occurring between solder bumps and connection electrodes even when an impact is applied. It is an object of the present invention to improve the reliability by preventing the problem. A semiconductor element, a wiring board having a configuration in which a plurality of on-board wirings connected to the semiconductor element are formed on an insulating substrate, and a wiring board having the same.
3A are arranged in an area array and the wiring on the substrate 2
8, a solder bump 25 joined to the connection terminal 29A formed on the semiconductor device 22 and a sealing resin 24 for sealing at least the semiconductor element 22.
9A is configured to have flexibility with respect to the insulating substrate 27A, and the impact load is reduced by the flexible deformation of the connection terminal 29A.

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 particular, the present invention relates to a semiconductor device in which bonding electrodes (bumps) are arranged in an area array. In recent years, with the miniaturization and high density of semiconductor devices, the terminal arrangement of semiconductor devices has been changed to QFP (Quad Fl
Attempts have been made to adopt an area array type arrangement such as a BGA (Ball Grid Array) instead of a peripheral type terminal arrangement such as at package).

[0002]

2. Description of the Related Art FIGS. 1 and 2 show a semiconductor device 1 having a BGA structure as an example of a conventional semiconductor device having an area array type terminal arrangement. Each figure shows a state in which the semiconductor device 1 is mounted on the mounting board 11, and FIG. 2 shows an enlarged view of the vicinity of the mounted solder bumps 5.

A semiconductor device 1 having a BGA structure generally includes a semiconductor element 2, a wiring board 3, a sealing resin 4, solder bumps 5 (spherical bonding electrodes), and the like. The semiconductor element 2 is mounted on the upper part of the wiring board 3,
Thereby, the semiconductor element 2 and the wiring board 3 are electrically connected. In the wiring board 3, on-board wiring 8 is formed in a predetermined pattern on the upper surface of an insulating substrate 7 made of, for example, resin.
At one end of the on-substrate wiring 8, a bonding pad to which the above-mentioned wire is connected is formed, and at the other end, a connection terminal 9 to which the solder bump 5 is joined is formed.

The solder bumps 5 are arranged on the wiring board 3 in an area array type terminal arrangement. For this reason, through holes 10 are formed in the insulating substrate 7 at positions where the solder bumps 5 are arranged. The connection terminals 9 are exposed from the insulating substrate 7 by forming the through holes 10, so that the upper portions of the solder bumps 5 are connected to the connection terminals 9 through the through holes 10.
It is configured to be joined to.

In the mounted state, the lower portion of the solder bump 5 is joined to the mounting-side electrode 12 formed on the mounting substrate 11, whereby the semiconductor element 2 is provided with the wires 6, the wiring 8 on the substrate, the connection terminals 9, Mounting board 1 via bump 5
1. Further, the sealing resin 4 is formed by molding (or potting) on the upper part of the wiring board 3, and the above-described semiconductor element 2,
It has a function of protecting the wires 6 and the wiring 8 on the substrate.

In the semiconductor device 1 having the above configuration,
In the related art, the size of the connection terminal 9 is set to be larger than the through hole 10 formed in the insulating substrate 7, so that the connection terminal 9 has a configuration in which the entire outer peripheral edge is fixed to the insulating substrate 7.

[0007]

By the way, in a leaded package such as QFP which has been widely used in the past,
Since the lead is interposed between the resin package (in which the semiconductor element is sealed) and the mounting substrate, even when a mechanical load such as bending occurs on the mounting substrate, the lead flexibly deforms the load. Accordingly, the load can be reduced and the load applied to the solder joint between the lead and the mounting board can be reduced.

On the other hand, in the area array type semiconductor device 1 such as BGA, the terminal arrangement (the arrangement of the solder bumps 5) is used.
Due to the above characteristics, the solder bonding area of each solder bump 5 can be made larger than that of QFP or the like to secure the bonding strength and to cope with mechanical loads such as bending of the mounting board. However, with respect to an impact load such as a drop impact, the destruction occurs instantaneously at the bonding interface 13 (shown in satin in FIG. 2) between the solder bump 5 and the connection terminal 9. Further, as described above, since the entire outer peripheral edge of the connection terminal 9 is fixed to the insulating substrate 7, the connection terminal 9 is not displaced, and the impact load is applied to the bonding interface 1.
3 will be applied directly.

Further, the connection terminals 9 are usually plated with nickel, gold, tin, or the like. A compound layer is formed. Since this intermetallic compound layer is generally hard and brittle, breakage is likely to occur at the joint interface 13 when the above-mentioned impact load is applied.

For this reason, the occurrence of breakage cannot be prevented by a slight increase in the joint area, and a reinforcing resin (underfill resin) is mounted for use in which such an impact load is expected. Filling between the substrate 11 and the semiconductor device 1 has been performed. However, in the configuration in which the reinforcing resin is loaded between the mounting substrate 11 and the semiconductor device 1,
This increases the number of parts and complicates the manufacturing process, and increases the cost of the semiconductor device 1.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and provides a semiconductor device capable of preventing breakage without using an underfill resin and improving reliability even when an impact is applied. The purpose is to provide.

[0012]

The above-mentioned object can be attained by taking the following means. According to the first aspect of the present invention, a semiconductor device, a wiring board having the semiconductor element mounted thereon and a plurality of wirings connected to the semiconductor element formed on an insulating substrate, and an area provided on the wiring board. A semiconductor device comprising: a plurality of connection terminals, wherein the plurality of connection terminals are arranged in an array and include a bonding electrode bonded to a connection terminal formed on the wiring.
A part or the whole thereof is configured to have flexibility with respect to the insulating substrate.

According to a second aspect of the present invention, in the semiconductor device according to the first aspect, a through hole is formed in the insulating substrate at a position where the bonding electrode is provided, and the connection terminal is connected to the through hole. It is characterized by being comprised so that it may be located inside. According to a third aspect of the present invention, in the semiconductor device according to the second aspect, the insulating substrate comprises:
At least between the sealing resin and the sealing resin formed on the wiring board so as to seal the semiconductor element, when the sealing resin is formed, the resin flows out to the side where the bonding electrode is provided through the through hole. And a resin leakage preventing member for preventing the occurrence of the resin is provided.

According to a fourth aspect of the present invention, there is provided a semiconductor device, and a wiring board having the semiconductor element mounted thereon and a plurality of wirings connected to the semiconductor element formed on an insulating substrate. A semiconductor device comprising: a bonding electrode that is arranged in an area array on the wiring substrate and bonded to a connection terminal formed on the wiring, and that is bonded to an electrode formed on the mounting substrate in a mounted state.
The connection terminal is made of a flexible material and is bonded to the insulating substrate, and the bonding strength of the connection terminal to the insulating substrate is higher than the bonding strength at which the bonding electrode is bonded to the mounting substrate. It is characterized in that it is configured to be weaker.

According to a fifth aspect of the present invention, in the semiconductor device according to any one of the first to fourth aspects, a width of the connection terminal is wider than a width of a wiring other than the connection terminal. It is characterized by having comprised so that it might become. Each of the means described above operates as follows.

According to the first aspect of the present invention, a part or all of the plurality of connection terminals to which the bonding electrodes are bonded have flexibility with respect to the insulating substrate. When an impact load such as a drop impact is applied to the semiconductor device mounted on the semiconductor device, the connection terminal is flexibly deformed, so that the impact load applied to the joint interface between the connection terminal and the joint electrode is reduced. Can be. Therefore, it is possible to prevent the occurrence of breakage between the connection terminal and the bonding electrode at the bonding interface, and to improve the reliability of the semiconductor device.

According to the second aspect of the present invention, a through-hole is formed in the insulating substrate at a position where the bonding electrode is provided, and the connection terminal is located in the through-hole.
The connection terminal is in a floating state in the through-hole, and is thus in a state capable of being flexibly deformed. Further, since the connection terminals can be configured to have flexibility only by forming the through holes while leaving the connection terminals on the insulating substrate, it is possible to easily and reliably form the flexible deformable connection terminals. it can.

Further, according to the third aspect of the invention, between the insulating substrate and the sealing resin, when the sealing resin is formed, the resin is prevented from flowing out to the side where the bonding electrode is provided through the through hole. By providing the resin leakage preventing member, it is possible to prevent the resin from adhering to the bonding electrode, and to improve the mounting reliability. According to the fourth aspect of the present invention, the connection terminal is made of a flexible material and is bonded to the insulating substrate, and the bonding electrode is bonded to the mounting substrate with respect to the bonding force of bonding to the mounting substrate. With the configuration in which the bonding strength to the insulating substrate is weaker, when an impact load is applied, damage occurs at the bonding interface between the connection terminal and the insulating substrate.

However, since the connection terminal is formed integrally with the wiring, even if the connection terminal is peeled off from the insulating substrate, there is no problem in electrical function. Also,
If an impact load is applied again after the joint interface has been broken, the connection terminals are applied to the joint interface between the connection terminals and the joint electrodes because the structure of the connection terminals is flexible with respect to the insulating substrate. Impact load can be reduced. Therefore, damage occurring between the connection terminal and the bonding electrode at the bonding interface can be more reliably prevented.

Further, according to the fifth aspect of the invention, the width of the connection terminal is made wider than the width of the wiring other than the connection terminal, so that the flexibility of the connection terminal is improved. Can be made larger than other parts, and the effect of reducing the impact load can be increased.

[0021]

Next, embodiments of the present invention will be described with reference to the drawings. 3 to 5 show the first embodiment of the present invention.
FIG. 6 is a diagram for explaining a semiconductor device 20A according to an embodiment. FIG. 3 is a sectional view of a main part of the semiconductor device 20A, and FIG.
FIG. 5 is an enlarged view showing the vicinity of the solder bump 25 of the semiconductor device 20A, and FIG. 5 is an enlarged view of a wiring board provided on the semiconductor device 20A.

The semiconductor device 20A according to the present embodiment is a semiconductor device having a BGA structure having an area array type terminal arrangement. The semiconductor device 20A roughly includes a semiconductor element 22, a wiring board 23A, a sealing resin 24, and a solder bump 25.
(Spherical bonding electrode), a resin leakage prevention member 35, and the like. The semiconductor element 22 is mounted on an upper part of the wiring board 23A, and a plurality of electrode pads 3
3 are formed. The wires 26 are connected to the electrode pads 33 as described later.

The wiring board 23A is roughly the insulating substrate 2
7A and on-substrate wiring 28. The insulating substrate 27A is a resin substrate such as a polyimide tape, for example, and a through hole 30 is formed at a position where a solder bump 25 described later is joined. The on-substrate wiring 28 is formed in a predetermined pattern on the insulating substrate 27A.
The on-substrate wiring 28 is formed, for example, by forming a copper foil on the entire upper surface of the insulating substrate 27A and then etching it to form a predetermined pattern. In addition, the formed on-substrate wiring 2
Reference numeral 8 denotes nickel plating, gold plating, tin plating, or the like, for ensuring solder wettability when the solder bump 25 is joined to the mounting board 31.

One end of the on-substrate wiring 28 is connected to the wire 26
Is formed, and the other end of the connection terminal 2 to which the solder bump 25 is bonded is formed.
9A is formed (see FIG. 5). Accordingly, the connection terminals 29A are also plated with nickel, gold, tin, or the like. The solder bumps 25 are disposed on the wiring board 23A in an area array type terminal arrangement. Therefore, the through holes 30 formed in the insulating substrate 27A are also formed in an area array type (lattice-like) arrangement. This through hole 3
By forming 0, the connection terminals 29A formed on the on-substrate wiring 28 are exposed from the insulating substrate 27A toward the mounting side. The solder bump 25 is configured to be joined to the connection terminal 29A via the through hole 30.

The sealing resin 24 is formed on the wiring substrate 23A by molding (or potting).
It has a function of protecting the semiconductor element 22, the wires 26, the wiring 28 on the substrate, and the like. Further, since the through-hole 30 is formed in the wiring board 23A as described above, if the sealing resin 24 is simply formed in the wiring board 23A, the resin constituting the sealing resin 24 is connected to the wiring via the through-hole 30. Substrate 2
It is conceivable that the solder 3A leaks out to the mounting side and the bonding property between the solder bump 25 and the mounting board 31 becomes poor.

For this reason, in the present embodiment, a resin leakage prevention member 35 is disposed above the wiring board 23A, and the through hole 30 is closed by the resin leakage prevention member 35, so that the resin is not formed when the sealing resin 24 is formed. Wiring board 2 through through hole 30
3A is prevented from leaking to the mounting side. Thereby, the bonding between the semiconductor device 20A and the mounting board 31 (ie,
The bonding between the solder bump 25 and the mounting-side electrode 32) can be reliably performed, and the mounting reliability can be improved.

In the mounted state, the lower portion of the solder bump 25 is soldered to the mounting-side electrode 32 formed on the mounting substrate 31, whereby the semiconductor element 22 is connected to the wire 26, the wiring 28 on the substrate, the connection terminal 29A, It is electrically connected to the mounting board 31 via the solder bump 25. Here, in the semiconductor device 20A having the above configuration, the connection terminal 29A
Attention is paid to the bonding structure between the solder bumps and the solder bumps 25, which will be described in detail below.

As described above with reference to FIGS. 1 and 2, in the conventional semiconductor device 1, the connection terminals 9 are provided so as to cover the through holes 10. On the other hand, it could not be displaced. On the other hand, in the semiconductor device 20A according to the present embodiment, the connection terminal 29A
Are configured to extend in a through-hole 30 in a cantilever manner. Specifically, as shown in FIG.
A is composed of a fixed portion 36 and a flexible deformable portion 37. The fixed portion 36 is fixed to the insulating substrate 27A,
The flexible deformation portion 37 is configured to extend displaceably into the through hole 30.

As described above, the connection terminal 29A is connected to the through hole 30.
The connection terminal 29A.
Is in a floating state in the through-hole 30.
The state shown in FIG. Further, the solder bump 25 is configured to be joined only to the flexible deformation portion 37. Also, simply the insulating substrate 2
Since the connection terminal 29A can be configured to be flexible only by forming the through hole 30 while leaving the connection terminal 29A in 7A, the flexible deformable connection terminal 29A can be easily and reliably formed.

As described above, since the connection terminal 29A is configured to be flexibly deformable with respect to the insulating substrate 27A,
When an impact load such as a drop impact is applied to the semiconductor device 20A mounted on the mounting board 31, the connection terminal 29A
Is flexibly deformed, so that an impact load applied to the joint interface between the connection terminal 29A and the solder bump 25 can be reduced.

That is, when an impact load is applied, the impact load is applied to the connection terminal 29A which has a large resistance to the intermetallic compound generated at the joint interface between the connection terminal 29A and the solder bump 25. As a result, the impact load is buffered by the flexible deformation of the connection terminal 29A. Thereby, the connection terminal 29 is formed at this joint interface.
The occurrence of breakage between A and the solder bump 25 can be prevented, and the reliability of the semiconductor device 20A can be improved.

In this embodiment, as shown in FIG. 5, the width dimension of the connection terminal 29A (indicated by an arrow L1 in the figure) is equal to the width dimension of the wiring other than the connection terminal (indicated by an arrow L2 in the figure). (L1> L2) (only three on-substrate wirings 28 are shown in FIG. 5 for simplicity). As described above, since the width of the connection terminal 29A is configured to be wider than the width of the wiring other than the connection terminal 29A, the flexibility of the connection terminal 29A is increased as compared with other portions of the wiring. Can be
The effect of alleviating the impact load can be increased. Also,
Since the width L1 of the connection terminal 29A can be set arbitrarily, it is possible to provide the connection terminal 29A with any flexibility.

Further, according to this embodiment, the semiconductor device 20
A can withstand an impact load without interposing an underfill resin between the semiconductor device 20 and the mounting substrate 31.
The manufacturing process of A can be simplified and the cost can be reduced. Note that the width L1 of the connection terminal 29A does not necessarily need to be set to be larger than the width L1 of the wiring other than the connection terminal 29A. As shown in FIG. May have the same width dimension (indicated by an arrow L3 in the figure).

Further, the structure of the connection terminal 29A is not necessarily required to be a cantilever structure, and in order to improve the strength of the wiring terminal, as shown in FIG. The shape may be a V-shape. Next, a second embodiment of the present invention will be described. 7 and 8 show a semiconductor device 2 according to a second embodiment of the present invention.
It is principal part sectional drawing which shows OB. 7 and 8, the same components as those of the semiconductor device 20A according to the first embodiment described above with reference to FIGS. 3 to 6 are denoted by the same reference numerals, and description thereof will be omitted.

The semiconductor device 20B according to the present embodiment uses a wiring substrate 23B having wirings formed on both upper and lower surfaces thereof. That is, the on-substrate wiring 40 is formed on the upper surface of the insulating substrate 27B, and the connection terminals 29D are formed on the lower surface of the insulating substrate 27B. Further, a through-hole electrode 38 is formed at a predetermined position on the insulating substrate 27B, and the connection terminal 29D is connected to the through-hole electrode 3.
8 to the on-substrate wiring 40. Therefore,
The connection terminal 29D to which the solder bump 25 is joined is drawn out to the upper surface of the insulating substrate 27B via the through-hole electrode 38.

A wiring protection film 39 made of an insulating resin or the like is formed on each of the upper and lower surfaces of the insulating substrate 27B. The wiring protective film 39 functions to protect the through-hole electrode 38 and the on-substrate wiring 40 and to prevent the resin from leaking to the mounting side through the hole of the through-hole electrode 38 when the sealing resin 24 is in the mode. To play. By the way, in the semiconductor device 20B according to the present embodiment, the connection terminal 29D is made of a material (copper) that can be flexibly deformed as in the first embodiment, and the connection terminal 29D is insulated as shown in FIG. It is configured to be joined to the substrate 27B. Further, the bonding strength of the connection terminal 29D to the insulating substrate 27B is set to be lower than the bonding strength of the solder bump 25 to the mounting substrate 31 (specifically, the mounting-side electrode 32).

When an impact load is applied to the semiconductor device 20B having the above-described structure, breakage occurs at the joint interface 40 between the connection terminal 29D and the insulating substrate 27B for the above-described reason. However, since the connection terminal 29D is configured to be integrally connected to the through-hole electrode 38, the connection terminal 29D does not fall off the insulating substrate 27B, and as shown in FIG. Only the state is peeled off from the insulating substrate 27B. However, even in the state shown in FIG. 8, the connection terminal 29D maintains the state of being electrically connected to the through-hole electrode 38 as described above, so that there is no problem in the electrical function. Absent.

When attention is paid to the state of the connection terminal 29D shown in FIG. 8, this state is the same as that of the connection terminal 29A (see FIGS. 3 and 4) shown in the first embodiment.
B is in a state where the connection terminal 29D can be flexibly deformed. Therefore, as shown in FIG. 8, when the impact load is applied again after the joint interface is broken once, the connection terminal 29D
This structure can be flexibly deformed with respect to the insulating substrate 27B, so that the impact load applied to the joint interface between the connection terminal 29D and the solder bump 25 can be reduced. Thereby, damage occurring between the connection terminal 29D and the solder bump 25 can be more reliably prevented, and the reliability of the semiconductor device 20B can be improved.

In each of the above embodiments, all the connection terminals 29 provided in each of the semiconductor devices 20A and 20B are provided.
A to 29D are configured to be flexibly deformable with respect to the insulating substrates 27A and 27B. However, it is not always necessary to configure all the connection terminals to be flexibly deformable. Only the connected connection terminals may be configured to be flexibly deformable.

[0040]

According to the present invention as described above, the following various effects can be realized. According to the invention described in claim 1, when an impact load such as a drop impact is applied,
The impact load applied to the joint interface between the connection terminal and the bonding electrode is reduced by the flexible deformation of the connection terminal, so that it is possible to prevent the occurrence of breakage between the connection terminal and the junction electrode at this joint interface. Thus, the reliability of the semiconductor device can be improved.

According to the second aspect of the present invention, since the connection terminals can be flexibly deformed simply by forming the through holes while leaving the connection terminals on the insulating substrate, the connection having flexibility is provided. The terminals can be formed easily and reliably.
According to the third aspect of the present invention, it is possible to prevent the resin from adhering to the bonding electrode, and to improve the mounting reliability.

According to the fourth aspect of the present invention, it is possible to more reliably prevent damage occurring between the connection terminal and the bonding electrode at the bonding interface. Furthermore, according to the fifth aspect of the present invention, the flexibility of the connection terminal can be increased as compared with other portions of the wiring, and thus the effect of reducing the impact load can be increased.

[Brief description of the drawings]

FIG. 1 is a diagram showing a state in which a semiconductor device, which is one example of the related art, is mounted on a mounting board.

FIG. 2 is an enlarged view of the vicinity of a bonding interface between a solder bump and a connection terminal in FIG. 1;

FIG. 3 is a diagram showing a state in which the semiconductor device according to the first embodiment of the present invention is mounted on a mounting substrate.

FIG. 4 is an enlarged view of the vicinity of a bonding interface between a solder bump and a connection terminal in FIG. 3;

FIG. 5 is a plan view of a wiring board used in the semiconductor device according to the first embodiment.

FIG. 6 is a diagram illustrating a modification of the connection terminal.

FIG. 7 is a view showing a state in which the semiconductor device according to the second embodiment of the present invention is mounted on a mounting board (part 1).

FIG. 8 is a view showing a state where the semiconductor device according to the second embodiment of the present invention is mounted on a mounting board (part 2).

[Explanation of symbols]

 Reference Signs List 20A, 20B Semiconductor device 22 Semiconductor element 23A, 23B Wiring board 24 Sealing resin 25 Solder bump 27A, 27B Insulating substrate 28, 40 Wiring on board 29A-29D Connection terminal 30 Through hole 31 Mounting board 32 Mounting side electrode 35 Resin leakage prevention Member 36 Fixed part 37 Flexible deformation part 38 Through-hole electrode 39 Wiring protective film 41 Joining interface

Claims (5)

[Claims] 1. A semiconductor device, a wiring board on which the semiconductor element is mounted and a plurality of wirings connected to the semiconductor element are formed on an insulating substrate, and an area array on the wiring board. A semiconductor device comprising: a plurality of connection terminals, wherein the plurality of connection terminals are partially or entirely flexible with respect to the insulating substrate. A semiconductor device comprising: 2. The semiconductor device according to claim 1, wherein a through hole is formed in the insulating substrate at a position where the bonding electrode is provided, and the connection terminal is located in the through hole. Characteristic semiconductor device. 3. The semiconductor device according to claim 2, wherein the sealing resin is formed between the insulating substrate and a sealing resin formed on the wiring substrate so as to seal at least the semiconductor element. A semiconductor device, comprising: a resin leakage preventing member for preventing resin from flowing out to a side where the bonding electrode is provided through the through hole. 4. A semiconductor device, a wiring board having the semiconductor element mounted thereon and a plurality of wirings connected to the semiconductor element formed on an insulating substrate, and an area array formed on the wiring board. A semiconductor device comprising: a bonding electrode disposed and joined to a connection terminal formed on the wiring, and a bonding electrode joined to an electrode formed on a mounting substrate in a mounted state, wherein the connection terminal has flexibility. The connecting electrode is bonded to the insulating substrate, and the bonding strength of the connection terminal to the insulating substrate is lower than the bonding strength of the bonding electrode bonded to the mounting substrate. Characteristic semiconductor device. 5. The semiconductor device according to claim 1, wherein a width of the connection terminal is wider than a width of a wiring other than the connection terminal. Semiconductor device.