JPH09246426A - Surface mounted type electronic component, wiring board, mounting board and mounting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate breakage check between a surface mounted type electronic component and a wiring board, by providing a single or a plurality of bump conduction connection means for conducting and connecting different dummy bumps. SOLUTION: In an IC package with bump 32, for example, an IC chip 41 is mounted on one surface 40A of a circuit board 40 by a wire bonding method and is sealed by a sealing resin 42, such as, epoxy, and bumps 43 are provided in two columns on the other surface 40B of the circuit board 40 along peripheral edge portions of the other surface 40B. The bumps 43, except for four dummy testing bumps 43A to 43D arranged at the corners of the circuit board 40, are electrically connected via through-holes to corresponding electrodes formed on the side of the one surface 40A of the circuit board 40. (The electrodes are conducted and connected to corresponding electrodes of the IC chip 41 via metal wires 44 made of a gold material).

Description

Detailed Description of the Invention

[0001]

[Table of Contents] The present invention will be described in the following order. TECHNICAL FIELD OF THE INVENTION Conventional technology (FIGS. 5 to 8) Problems to be solved by the invention (FIGS. 5 to 8) Means for solving the problems (FIGS. 1 to 4) Embodiments of the invention (FIGS. 1 to 4) Effect of the invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount type electronic component, a wiring board, a mounting board and a mounting method.
GA (Ball Grid Array) and CSP (Chip Size Pack)
age) etc., IC package that has multiple bumps for signal input / output on one surface and is mounted by face-down,
A printed wiring board corresponding to the IC package, I
It is suitable to be applied to a mounting board in which a C package is mounted on a printed wiring board and a mounting method of this IC package.

[0003]

2. Description of the Related Art Conventionally, as one of IC packages for mounting an IC chip on a printed wiring board, there is a plastic QSP (Quad Flat Package). Normally, in this type of IC package, as shown in FIG. 5, a plurality of leads 3 formed in a gull wing shape are formed on a peripheral side surface of the package main body 2 by a predetermined pitch so as to project therefrom. At present, this QFP1 is the mainstream of IC packages.

However, in the QFP 1, the lead 2 is becoming narrower with the recent trend toward higher integration and higher pin count of semiconductor elements, which requires advanced packaging technology. Therefore, in recent years, as an IC package that can be easily mounted by the existing mounting technology, for example, BGA or CS.
P is receiving attention.

Actually, as shown in FIG. 6, in the BGA 10, the IC chip 12 is mounted on the one surface 11A of the circuit board 11 by the wire bonding method, and the IC chip 12 is sealed by the sealing resin 13 such as epoxy. A protrusion electrode (hereinafter referred to as a bump) 14 formed of a metal ball is sealed (or the IC chip 12 is covered with a cap such as a metal), and the other surface of the circuit board 11 is, for example, 1.5.
It is formed by forming a matrix with pitches of about [mm].

In this case, each bump 14 is electrically connected to a corresponding electrode formed on one surface 11A of the circuit board 11 (a corresponding electrode of the IC chip 12 via a metal wire 15 made of a gold material). ) Is electrically connected to the inner layer and through holes.

Thus, in the BGA 10, after positioning and mounting the printed wiring board at a predetermined position by face-down, the solder (and / or each bump 14) previously supplied on the corresponding electrode of the printed wiring board is melted by heating. Since the bumps 14 can be mounted by being joined to the corresponding electrodes of the printed wiring board, there is an advantage that they can be easily mounted within the range of the conventional mounting technology.

On the other hand, the SCP uses an insulating film made of polyimide or the like in which a circuit board similar to the BGA 10 or a metal foil is laminated, and an IC chip is formed by a flip chip method so that the mounting area does not become large on one side of the circuit board or the insulating film. It is mounted and mounted on the other side of the circuit board or insulating film by forming bumps made of metal balls in a matrix shape with, for example, 0.5 [mm] pitches, and is approximately the same size as an IC chip as a whole. Is formed in.

Therefore, even in this SCP, the BGA10
It can be mounted on a printed wiring board in the same manner as, and can be easily mounted by a conventional mounting technique. Note that the BGA is shown in FIG.
10 (FIG. 6) and an example of the back surface configuration of an IC package (hereinafter, referred to as an IC package with bumps) 18 in which a plurality of signal input / output bumps 17 are provided on the back surface 16A side of the package body 16 such as CSP. FIG. 8 shows a configuration example of a conventional mounting substrate 20 in which a plurality of such IC packages with bumps 18 are mounted on a printed wiring board 19.

[0010]

By the way, for example, QF
In an IC package in which the leads 3 are gull-wing type as shown in P1 (FIG. 5), the joint between each lead 3 and the corresponding electrode of the printed wiring board is exposed in the periphery of the IC package. It is possible to visually confirm the joining state (presence or absence of breakage, etc.).

However, in the IC package 18 with bumps (FIG. 7) such as the BGA 10 (FIG. 6) or the CSP,
As described above, since the bumps 17 are formed on the back surface 16A side of the package body 16 and mounted by face-down,
After mounting, the joint between each hump 17 and the corresponding electrode of the printed wiring board 19 (FIG. 8) was covered by the package body 16 and was difficult to see.

Therefore, conventionally, such an IC with bumps is used.
Printed wiring board 19 for package 18 (FIG. 7)
The broken state of the joint with (Fig. 8) is inspected by sending a signal to the circuit to check the operation of each IC one by one. Therefore, the inspection work of such a broken state is complicated. There was a problem that took a lot of time. IC with pump
Printed wiring board 19 for package 18 (FIG. 7)
The work of confirming the broken state with (FIG. 8) requires a dedicated jig such as an IC tester or an inspection device, which causes a problem that the cost is high.

The present invention has been made in view of the above points, and an object thereof is to propose a surface mounting type electronic component, a wiring board, a mounting board, and a mounting method capable of simplifying a fracture inspection.

[0014]

In order to solve such a problem, in a first aspect of the invention, a plurality of dummy bumps are provided on one surface side in a surface mount type electronic component having a plurality of signal input / output bumps formed on one surface side. Of the dummy bumps, a pair of different dummy bumps are conductively connected by a single or a plurality of bump conductive connecting means.

In the second invention, as the wiring board corresponding to the surface mount type electronic component of the first invention, a plurality of second electrodes respectively corresponding to the dummy bumps and predetermined first electrodes different from each other are provided. A third electrode and a fourth electrode conductively connected to the mounting surface, and when the surface-mounted electronic component is mounted, the third electrode and the dummy bump and the bump conductive connecting means together with the third and fourth electrodes are formed. A single or a plurality of electrode conductive connection means for conductively connecting a pair of different second electrodes are provided so as to form a continuous conductive path for conductively connecting the electrodes.

Further, in the third invention, the mounting board is formed by mounting the surface mount type electronic component of the first invention on the wiring board of the second invention.

Further, in a fourth aspect of the present invention, there is provided a mounting method for mounting a surface mounting type electronic component having a plurality of bumps for signal input / output formed on one surface thereof on a mounting surface of a wiring board.
A plurality of dummy bumps are provided on one surface side of the surface-mounted electronic component, and a pair of different dummy bumps are electrically connected by a single or a plurality of bump conduction connection means, while a plurality of dummy bumps corresponding to the dummy bumps are provided on the mounting surface of the wiring board. A second electrode, a third electrode and a fourth electrode which are conductively connected to different first electrodes, respectively, are formed, and when the surface mount electronic component is mounted, the second electrode, the dummy bump, and Third and fourth together with bump conduction connecting means
And a first step for conductively connecting a pair of different second electrodes by one or a plurality of electrode conductive connecting means so as to form a continuous conductive path for conductively connecting the electrodes of FIG. The second step is provided.

In this case, in the first and second inventions,
When the surface-mounted electronic component of the first invention is mounted on the wiring board of the second invention, each dummy bump and bump conduction connection means of the surface-mounted electronic component, and the second electrode and electrode conduction connection of the wiring board. By means of the means, a conduction path for electrically connecting the third and fourth electrodes of the wiring board is formed.

Therefore, for example, when any one of the dummy bumps is broken, the resistance value between the third and fourth electrodes is larger than that when it is not broken.
It is possible to inspect whether or not each dummy bump is broken by simply measuring the resistance value between the third and fourth electrodes, and thus, using this dummy bump as a sample, between the surface mount electronic component and the wiring board. Breakage inspection can be performed.

Also in the third and fourth inventions, the third
And, it is possible to inspect whether or not each dummy bump is broken only by measuring the resistance value between the fourth electrode,
In this way, it is possible to perform a breakage inspection of the mounting substrate using this dummy bump as a sample.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

In FIG. 1, reference numeral 30 generally indicates a mounting board according to the embodiment, and a plurality of IC packages 32 with bumps are mounted on a mounting surface 31A of a printed wiring board 31 on which a predetermined wiring pattern is formed. Has been formed. In the bumped IC package 32, as shown in FIGS. 2 and 3, respectively, one surface 40 of the circuit board 40
An IC chip 41 is mounted on A by a wire bonding method, the IC chip 41 is sealed with a sealing resin 42 such as epoxy, and the other surface 4 of the circuit board 40 is sealed.
The bumps 43 are formed on the 0B side by being arranged in two rows along the peripheral edge portion of the other surface 40B.

Each of the bumps 43 is composed of four dummy bumps (hereinafter, referred to as first to fourth inspection bumps) 43A to 43D respectively arranged at the corners of the other surface 40B of the circuit board 40. 3) except for the corresponding electrodes formed on the one surface 40A side of the circuit board 40 (the IC chip 41 via the metal wires 44 each made of a gold material).
Are electrically connected to the corresponding electrodes of the above) and are electrically connected through through holes (not shown).

Further, as is particularly apparent in FIG. 3, the first and second inspection bumps 43A and 43B are formed on the circuit board 40.
While being conductively connected via the wiring line 45A formed on the other surface 40B, similarly, the third and fourth inspection bumps 43C and 43D are also conductively connected via the wiring line 45B.

On the other hand, in the printed wiring board 31, the bumps 4 of the IC package 32 with bumps are mounted on the mounting surface 31A.
Lands 50 are formed so as to correspond to the respective Nos. 3 and 3.
In this case, of these lands 50, a land to which the first inspection pin 43A of the IC package 32 with bumps is bonded (hereinafter, referred to as a first inspection land) 50A.
And the third inspection pin 4 of the IC package 32 with bumps
A land (hereinafter, referred to as a third inspection land) 50C to which 3C is joined is electrically connected by a wiring line 51.

The mounting surface 31 of the printed wiring board 31
At A, the first and second check lands 53A and 53B are thrown away from the area facing the IC package 32 with bumps, and these first and second check lands 53A and 53B are respectively connected to the wiring line. 52A, 52
Land to which the corresponding fourth inspection bump 43B is joined via B (hereinafter, referred to as a fourth inspection land)
50D or a land (hereinafter, referred to as a second inspection land) 50B to which the second inspection bump 43B is joined is electrically connected.

As a result, in this printed wiring board 31, when the above-mentioned bumped IC package 32 is mounted, the first and second check lands 53A and 53B are provided.
Is the wiring line 52A, the fourth inspection land 50D, and the fourth
Inspection bump 43D (FIG. 3), wiring line 45B (FIG. 3), third inspection bump 43C (FIG. 3), third inspection land 50C, wiring line 51, first inspection land 50A, First inspection bump 43A (FIG. 3), wiring line 45A (FIG. 3), second inspection bump 43B (FIG. 3), second inspection land 50B and wiring line 52A.
Are electrically connected via the.

In the above structure, the bumped IC package 32 is mounted on the printed wiring board 31 in a state where none of the first to fourth inspection bumps 43A to 43D of the bumped IC package 32 is broken. The first and second check lands 53A, 53B
Is the wiring line 52A, the fourth inspection land 50D, the fourth inspection bump 43D (FIG. 3), the wiring line 45B (FIG. 3), the third inspection bump 43C (FIG. 3), as described above. Third inspection land 50C, wiring line 51, first inspection land 50A, first inspection bump 43A
(FIG. 3), the wiring line 45A (FIG. 3), the second inspection bump 43B (FIG. 3), the second inspection land 50B, and the wiring line 52A are electrically conductively connected by a continuous conductive path. Therefore, when the first or second terminal of the tester is brought into contact with each of the first and second check lands 53A and 53B, a predetermined resistance value (hereinafter, referred to as the first resistance value) is measured as a measurement value. Called) is obtained.

On the other hand, the bumped IC package 32 is in a state where any of the first to fourth inspection bumps 43A to 43D of the bumped IC package 32 is broken.
Is mounted on the printed wiring board 31, the conduction of the first and second check lands 53A and 53B is the broken first to fourth inspection bumps 43A to 43D.
When the first or second terminals of the tester are brought into contact with the first and second check lands 53A and 53B, respectively, a resistance value larger than the first resistance value is obtained as a measurement value. To be

Here, this IC package with bumps 32
In the IC package with bumps in which a plurality of bumps for signal input / output are formed on the back surface as described above, the main cause of the break between the bumps and the corresponding lands of the printed wiring board is
Due to the difference in coefficient of thermal expansion between the printed wiring board and the IC package with bumps, the heat generated during the operation of the IC chip causes a mismatch in expansion and contraction between the IC package with bumps and the printed wiring board, resulting in stress (strain). ) Is applied to the bump which is the joint between the IC package with bumps and the printed wiring board.

In this case, the largest expansion / contraction difference between the IC package with bumps and the printed wiring board is in the vicinity of the peripheral edge of the IC package with bumps, and accordingly, the bumps provided on the back side of the IC package with bumps are the same. home,
Since the stress concentrates most on each bump placed in the corner,
It has been confirmed by the applicant of the present invention that the bumps at the corners are likely to break.

Therefore, as in this embodiment, an IC with bumps is provided.
By configuring the package 32 and the printed wiring board 31, it is only necessary to measure the resistance value between the first and second check lands 53A and 53B of the printed wiring board 31, and Using the bumps 43A to 43D as a sample, the fracture inspection of the joint between the bumped IC package 32 and the printed wiring board 31 can be performed with high accuracy and easily.

According to the above construction, the back surface (circuit board 40) of the bump IC package 31 on which each bump 43 is provided.
First to fourth dummy bumps formed on the corners of the other surface 40B)
Of the inspection bumps 43A to 43D, and among the first to fourth inspection bumps 43A to 43D, between the first and second inspection bumps 43A and 43B and between the third and fourth inspection bumps 43A to 43D. The wiring bumps 43C and 43D are electrically connected to each other by wiring lines 45A and 45B, respectively, while the mounting surface 31A of the printed wiring board 31 is connected to the first to fourth inspection bumps 43A to 43D of the IC package 31 with bumps. Corresponding first to fourth inspection lands 50A to 50, respectively
D and the first and second check lands 53A that are conductively connected to the fourth or second inspection lands 50D and 50B,
53B and first and third inspection lands 50A and 50C
By providing the wiring line 51 for conductively connecting the ICs with each other, the broken state of the joint between the bumped IC package 32 and the printed wiring board 31 can be inspected almost accurately and easily. It is possible to realize an IC package with bumps, a printed wiring board, a mounting board, and an inspection method that can simplify the fracture inspection.

In the embodiment described above, the present invention is applied to the IC package 32 with bumps configured as shown in FIGS. 2 and 3, the printed wiring board 31 on which the IC package 32 with bumps is mounted, and the IC package with bumps. A mounting board 30 in which 32 is mounted on the printed wiring board 31.
However, the present invention is not limited to this, and various other surface mount type electronic components in which a plurality of bumps (projection electrodes) for signal input / output are provided on one surface side, It can be applied to a wiring board and a mounting board on which surface-mounted electronic components are mounted.

In the above embodiment, the bumped I
Regarding the case where the first to fourth inspection bumps 43A to 43D formed on the back surface of the C package 32 (the other surface of the circuit board 40) are formed on the respective corners of the back surface of the IC package 32 with bumps. However, the present invention is not limited to this, and the formation positions of the first to fourth inspection bumps 43A to 43D may be positions other than the corners of the back surface of the bumped IC package 32. Inspection bump 4
The number of 3A to 43D may be four or more.

Further, in the above embodiment, the first and second inspection bumps 43A and 43B and the third and fourth inspection bumps 4 are provided on the side of the IC package 32 with bumps.
3C and 43D are electrically connected by the wiring lines 45A and 45B, respectively, and the first and third inspection lands 50A and 50C are electrically connected by the wiring line 51 on the printed wiring board 31 side. However, the present invention is not limited to this, and the point is that when the IC package 32 with bumps is mounted on the printed wiring board 31, the first to fourth inspection lands 50A to 50D and the first to fourth inspection lands 50A to 50D.
~ One or a plurality of first wiring lines that electrically connect a predetermined pair of first to fourth inspection lands 50A to 50D among the fourth inspection lands 50A to 50D, and first to fourth
Inspection bumps 43A to 43D and a predetermined pair of first bumps 43A to 43D among the first to fourth inspection bumps 43A to 43D.
-The first and second wiring lines for electrically connecting the fourth inspection bumps 43A to 43D are connected to the first and second wiring lines.
If it is possible to form a continuous conductive path that electrically connects the check lands 53A and 53B, the combination of the formation positions of the first and second wiring lines is:
Various other combinations can be applied.

Furthermore, in the above-described embodiment, the first and second inspection bumps 43 of the IC package 32 with bumps are provided.
A, 43B, third and fourth inspection bumps 43C, 43
As a bump conduction connecting means for electrically connecting D respectively,
Although the case where the wiring lines 45A and 45B are applied has been described, the present invention is not limited to this, and for example, a lead wire may be used, and the first and second inspections of the bumped IC package 32 may be performed. Bumps 43A, 43B,
Various other bump conduction connecting means can be applied as the bump conduction connecting means for conducting and connecting the third and fourth inspection bumps 43C and 43D, respectively.

Similarly, in the above-described embodiment, the first and third inspection lands 50A of the printed wiring board 31,
The case where the wiring line 51 is applied as the electrode conduction connecting means for conducting conduction connection of 50C has been described, but the present invention is not limited to this, and the point is that the first of the printed wiring board 31 is used.
-Fourth inspection lands 50A-50D, first-fourth inspection bumps 43A-43 of the IC package 32 with bumps
If it is possible to form a continuous conductive path that makes a conductive tangent line between the first and second check lands 53A and 53B together with the D and the wiring lines 45A and 45B, for example, a lead wire or the like may be used. Of course, various other electrode conductive connection means can be applied as the electrode conductive connection means for conductively connecting the first and third inspection lands 50A and 50C of the printed wiring board 31.

[0039]

As described above, according to the present invention, a plurality of dummy bumps are provided on one surface side of a surface mount type electronic component, and a pair of different dummy bumps are electrically connected by a single or a plurality of bump conduction connecting means. , A plurality of second electrodes respectively corresponding to the dummy bumps of the surface-mounted electronic component, and third and fourth electrodes conductively connected to different predetermined first electrodes on the mounting surface of the wiring board. When formed and surface-mounted electronic components are mounted, the second
Of electrodes, dummy bumps, and bump conduction connection means so that a pair of different second electrodes are electrically connected by a single or a plurality of electrode conduction connection means so as to form a continuous conduction path for electrically connecting the third and fourth electrodes. By making the connection, the breakage inspection between the surface mount type electronic component and the wiring board can be performed only by measuring the resistance value between the third and fourth electrodes, thus simplifying the breakage inspection of the mount board. It is possible to realize a surface mount electronic component, a wiring board, a mounting board and a mounting method that can be realized.

[Brief description of drawings]

FIG. 1 is a plan view showing a configuration of a mounting board according to an embodiment.

FIG. 2 is a cross-sectional view showing a configuration of an IC package with bumps according to an embodiment.

FIG. 3 is a plan view showing a configuration of an IC package with bumps according to an embodiment.

FIG. 4 is a schematic plan view showing a configuration of a printed wiring board according to an example.

FIG. 5 is a perspective view showing a configuration of a QFP.

FIG. 6 is a cross-sectional view showing the structure of a BGA.

FIG. 7 is a plan view showing a configuration example of a conventional IC package with bumps.

FIG. 8 is a plan view showing a configuration of a conventional mounting board.

[Explanation of symbols]

30 ... Mounting board, 31 ... Printed wiring board, 31A ...
… Mounting surface, 32 …… Bumped IC package, 41 ……
IC chip, 43 ... Bump, 43A to 43D ... Inspection bump, 45A, 45B, 51, 52A, 52B ...
Wiring line, 50 ... Land, 50A to 50D ... Inspection land, 53A, 53B ... Check land.

Claims (8)

[Claims] 1. A surface-mounted electronic component having a plurality of bumps for signal input / output formed on one surface side, wherein a plurality of dummy bumps provided on the one surface side and a pair of dummy bumps respectively different from each other are electrically connected. Alternatively, a surface mount type electronic component comprising a plurality of bump conductive connecting means. 2. The surface mount electronic component according to claim 1, wherein each of the dummy bumps is provided in a corner portion on the one surface side. 3. A wiring board for mounting a surface mount type electronic component having a plurality of signal input / output bumps on one surface side, the wiring board being formed on the mounting surface for mounting the surface mount component in correspondence with each of the bumps. A plurality of first electrodes, a plurality of second electrodes formed on the mounting surface corresponding to a plurality of dummy bumps provided on the one surface side of the surface mount electronic component, and among the mounting surface When the surface mounting electronic component is mounted, third and fourth electrodes which are formed so as to avoid the area facing the surface mounting electronic component and are conductively connected to the predetermined different first electrodes, respectively. And one or more bump conductive connecting means for conductively connecting the second electrode, the dummy bump, and a pair of different dummy bumps, respectively, and a conductive connection for the third and fourth electrodes. A wiring board comprising a single or a plurality of electrode conductive connecting means for conductively connecting a pair of different second electrodes so as to form a continuous conductive path. 4. The second electrodes correspond to the dummy bumps respectively provided at the corners on the one surface side of the surface mount electronic component,
The wiring board according to claim 3, wherein each of the mounting surfaces is formed at a corner of the facing area of the surface-mounted electronic component. 5. A mounting board in which a surface mounting type electronic component is mounted on a mounting surface of a wiring board, wherein the surface mounting type electronic component has a signal output provided on one surface side which is a surface facing the wiring board. The wiring board includes a plurality of bumps for input, a plurality of dummy bumps provided on the one surface side, and a single or a plurality of bump conductive connecting means for conductively connecting a pair of different dummy bumps, respectively, A plurality of first electrodes formed on the mounting surface corresponding to the bumps of the electronic component, and a plurality of first electrodes formed on the mounting surface corresponding to the dummy bumps of the surface mount electronic component. A second electrode, third and fourth electrodes formed around the second electrode on the mounting surface and electrically conductively connected to different first electrodes, respectively, and the surface Different from each other so that when the electronic component is mounted, the second electrode, the dummy bump, and the bump conductive connection means form a continuous conductive path for conductively connecting the third and fourth electrodes. A pair of the second
And a plurality of electrode conductive connecting means for conductively connecting the electrodes of 1. 6. The dummy bumps of the surface-mounted electronic component are respectively provided at the corners on the one surface side of the surface-mounted electronic component, and the second electrodes correspond to the dummy bumps, respectively. The mounting board according to claim 5, wherein the mounting board is formed at a corner portion of a region facing the surface-mounted electronic component, of the mounting surface. 7. A mounting method for mounting a surface mounting type electronic component having a plurality of bumps for signal input / output formed on one side thereof on a mounting surface of a wiring board, wherein a plurality of surface mounting type electronic components are provided on the one side. While providing the dummy bumps, the pair of different dummy bumps are conductively connected by a single or a plurality of bump conductive connecting means, on the mounting surface of the wiring board, to the bumps or the dummy bumps of the surface mount electronic component. A plurality of corresponding first and second electrodes, and third and fourth conductively connected to the respective different predetermined first electrodes.
Of the second electrode, the dummy bump, and the bump conductive connection means, and when the surface-mounted electronic component is mounted, the third electrode and the fourth electrode are electrically connected. A first step for conductively connecting a pair of different second electrodes by one or more electrode conductive connecting means so as to form a conductive path; and positioning the surface mount electronic component on the wiring board. And a second step of joining the bump and the dummy bump of the surface-mounted electronic component to the corresponding first or second electrode of the wiring board after mounting. 8. In the first step, each of the dummy bumps is provided at a corner of the one surface side of the surface mount electronic component, and each of the second electrodes is associated with each of the dummy bumps. Then, the mounting method is characterized in that it is formed at a corner of a region facing the surface-mounted electronic component on the mounting surface.