JPH11185913A - Bga package socket - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability of electrical connection with BGA(ball grid array) package bumps. SOLUTION: A connection terminal 3 electrically connected with a bump 9 by a BGA package 8 being mounted is provided at a bottom face of an opening of a socket body. The connection terminal 3 has a contact part 5 supported to the socket body by a support part 4. The contact part 5 is composed of four contact plates 6, and each plate 6 is opposed to one another, and is disposed so as to sandwich a side part of the bump 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a BGA (ball
The present invention relates to a socket used when mounting a (grid array) package on a printed circuit board of an electronic device such as a computer, and particularly to a structure of an electrical contact portion thereof.

[0002]

2. Description of the Related Art A BGA package is a package in which spherical bumps formed of solder or the like are provided on the back surface. A socket used for mounting such a BGA package on a printed circuit board has a spring property. A contact structure is provided in which the processed conductor is pressed against the tip of the bump to make electrical connection with the bump.

As an example of this type of conventional socket, FIGS. 7 to 9 show a socket disclosed in Japanese Patent Application Laid-Open No. 59-218762. 7 is a perspective view of a conventional socket for a BGA package, and FIG. 8 is a cross-sectional view showing the socket shown in FIG. 7 with a BGA package mounted. FIG. 9 is a cross-sectional view showing various forms of the connection terminal of the socket shown in FIG.

[0004] As shown in FIGS. 7 and 8, the socket body 102 formed of plastic is a box-shaped member having an accommodation chamber 102 a for accommodating a BGA package 108. A claw-shaped stopper 102b that engages with a recess provided on the side surface of the BGA package 108 is integrally provided on the side surface of the accommodation room 102a.
The bump 109 of the BGA package 108 is
Is provided with a connection terminal 103 to which is contacted. The connection terminal 103 is configured to be elastically deformable in the mounting / removing direction of the BGA package 108. When the socket body 102 is mounted on a printed circuit board (not shown),
The connection terminal 103 is electrically connected to the conductor pattern on the printed circuit board.

The BGA package 108 is connected to the socket body 1
02, the recess of the BGA package 108 engages with the claw-shaped stopper 102b and the BGA
The package 108 is fixed. The connection terminal 103 is pressed by the bump 109 and is elastically deformed and pressed against the tip of the bump 109, whereby the bump 109 and the connection terminal 103 are electrically connected.

FIG. 9A shows an example of the connection terminal 103.
As shown in FIG. 9, a connection terminal body 123 made of an S-shaped metal spring 113 or a conductive rubber having a large elastic elasticity as shown in FIG. 9B.
A metal contact 123b is attached to the upper and lower ends of a.

[0007]

However, the above-mentioned conventional socket has the following problems.

First, the reliability of the electrical connection between the bump and the connection terminal is low. As described above, the connection terminal presses only one point at the tip of the bump. Therefore, if foreign matter enters this one point, good electrical connection is not made, and the possibility of poor contact increases. Further, even when foreign matter does not enter the connection point between the connection terminal and the bump, the tip of the bump may be crushed because a large force is constantly applied to the tip of the bump. When the bumps are crushed, the amount of deformation of the connection terminal decreases, and the pressing force by the connection terminal decreases accordingly.
As a result, a desired pressing force cannot be secured gradually, and a connection failure between the bump and the connection terminal may occur.

Second, the positional accuracy of the connection terminals must be strictly defined. As described above, since the connection terminal makes contact with the tip of the bump only at one point and is elastically deformed only in the mounting direction of the BGA package, in order to secure a desired pressing force, the position of the contact point with the bump, that is, It is necessary to strictly regulate the positional accuracy of the connection terminal with respect to the socket body. As a result, the inspection and management man-hours in the design and manufacturing process of the socket have increased, which has caused a cost increase.

Accordingly, an object of the present invention is to provide a socket that improves the reliability of electrical connection with bumps of a BGA package. Another object of the present invention is to provide a socket which can perform reliable electrical connection without strictly defining the positional accuracy of the connection terminal and which is excellent in productivity.

[0011]

In order to achieve the above object, a socket for a BGA package according to the present invention is a socket used for mounting a BGA package having a plurality of bumps provided on one principal surface on a substrate. A socket body provided with an opening for accommodating the BGA package, and a plurality of connections provided on the bottom surface of the opening of the socket body in correspondence with the bumps and electrically connected to the bumps, respectively. A terminal portion, and each of the connection terminals is made of a conductive material, and has a contact portion that sandwiches and presses the side portion of the bump at a plurality of locations when the BGA package is housed in the socket body. Have.

In the BGA package socket of the present invention configured as described above, the contact portions of the connection terminals are electrically connected to the bumps by inserting the BGA package into the socket body. Here, each contact part presses by sandwiching the side part of the bump at multiple places, so even if foreign matter adheres to one part of the connection terminal, the contact part can be electrically connected to the bump at another part It is. In addition, since the contact portion presses the bump at a plurality of locations, the force applied per location can be reduced, and the deformation of the bump over time due to the force applied to the bump is suppressed. As a result, the necessary pressing force between the bump and the contact portion is maintained for a long time. As described above, as the structure of the contact portion that sandwiches the side portion of the bump at a plurality of positions, the contact portion may be configured by a plurality of contact plates. In this case, the BGA package is housed in the socket body. Sometimes, each contact plate may be arranged to surround the side of the bump.

[0013] Further, by supporting the contact portion on the bottom surface of the opening of the socket main body by a support portion made of a material having elasticity and conductivity, the relative position between each connection terminal and the corresponding bump is adjusted. Even if it is off,
The contact portion can be electrically connected to the bump following the shift. In this case, by making the supporting portion a curved rod-shaped member, the contact portion can be displaced in any direction according to the position of the bump.

[0014]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a BGA according to an embodiment of the present invention.
It is a schematic perspective view of the socket for packages. FIG.
FIG. 2 is a perspective view showing one of connection terminals of the socket shown in FIG. 1 in a state where a bump of a BGA package is inserted.

As shown in FIG. 1, this socket 1 is made up of a box-shaped socket main body 2 made of plastic having an accommodation chamber 2a and a plurality of connection terminals 3 provided on the bottom surface of the accommodation chamber 2a. Have. A BGA package 8 (see FIG. 2) is accommodated in the accommodation room 2a with its bump 9 (see FIG. 2) facing downward. The upper end of the accommodation room 2a is used to facilitate insertion of the BGA package 8. Is spread in a tapered shape. The connection terminals 3 are arranged corresponding to the arrangement of the bumps 9 of the BGA package 8, and are electrically connected to the bumps 9 of the BGA package 8 by inserting the BGA package 8 into the storage room 2 a. In FIG. 1, only some of the connection terminals 3 are shown.

Here, the structure of the connection terminal 3 will be described with reference to FIG. The connection terminal 3 includes a support part 4 whose lower end part is press-fitted into the socket body 2 (see FIG. 1), and a contact part 5 provided at the upper end of the support part 4 to receive the bump 9 of the BGA package 8. . Each of the support portion 4 and the contact portion 5 is made of a conductive material having elasticity, and both are electrically and mechanically connected. The support portion 4 and the contact portion 5 may be integrated or separate. As the support portion 4 and the contact portion 5, for example, a metal spring material such as phosphor bronze can be used. The contact part 5 has a bump 9 to be received.
And four contact plates 6 which are arranged so as to surround from the side and which come into contact with different portions of the side portions of the bumps 9 when the bumps 9 are received in the contact portions 5, respectively. Each contact plate 6 is a flat plate-shaped member integrated at the lower end supported by the support portion 4, and is in point contact with the bump 9. Further, each contact plate 6 is curved such that the space between the opposing members widens upward (in a direction from the bottom surface of the housing chamber 2a of the socket body 2 toward the open end). The minimum distance between the opposing members of each contact plate 6 and the curvature of each contact plate 6 are such that when the contact portion 5 receives a bump, each contact plate 6
Is designed to be pressed or spread with a desired pressing force against each contact point CP with the bump 9.

The support portion 4 is a rod-shaped portion having a curved intermediate portion, and is elastically deformable in each of the X, Y, and Z directions. Thereby, the support portion 4 can displace the contact portion 5 in each of the X, Y, and Z directions. Further, the lower end of the support portion 4 penetrates the socket body 2 and protrudes from the lower surface of the socket body 2. When the socket 1 is mounted on a printed board (not shown), this portion corresponds to the conductor pattern of the printed board. Electrically connected.

Next, the mounting operation of the BGA package 8 to the socket 1 will be described with reference to FIGS.

FIG. 3 shows a BGA package 8 in the socket 1.
Shows the state before inserting the. Here, one bump 9b of the plurality of bumps 9a and 9b of the BGA package 8 is provided so as to be shifted from a regular position.
With respect to the insertion direction of the A package 8, the center axis of the bump 9b is shifted by a distance a from the center axis of the corresponding contact portion 5 of the connection terminal 3.

FIG. 4 shows a state in which the BGA package 8 is being pushed into the housing chamber 2a of the socket body 2. In this process, the BGA package 8 is guided to the accommodation room 2a while being guided by the tapered portion 2b at the upper end of the socket body 2. At this time, the contact portion 5
Each contact plate 6 has a curved shape such that the area of the surrounding area increases as it goes upward, so that even if the position of the bump 9 b is shifted, the bump 9 b is a space surrounded by the contact plate 6. Accepted within. further,
Since the contact portion 5 is elastically supported by the support portion 4, the contact portion 5 that has received the bump 9b is displaced following the position of the bump 9b. In the state shown in FIG. 4, the distance between the center axis of the bump 9b and the center axis of the corresponding contact portion 5 of the connection terminal 3 is smaller than the state shown in FIG.

FIG. 5 shows that the BGA package 8 has the socket 1
2 shows a state in which it is completely mounted. In this state,
Regarding the bump 9b having a displacement, the bump 9
The contact portion 5 is displaced until the distance between the center axis of the contact terminal b and the center axis of the contact portion 5 of the corresponding connection terminal 3 becomes almost zero, and all the contact plates 6 are brought into contact with the bumps 9b. . When the BGA package 8 is pushed in, the contact plates themselves are elastically deformed by the bumps 9b, and each contact plate 6 applies a force F
Then, the side portions of the bumps 9b are pressed so as to be sandwiched between opposing members. This is the same for the other bumps 9a. Thereby, the bumps 9a and 9b and the connection terminals 3
Electrical connection is made.

As described above, the contact portion 5 is
It is configured by a single contact plate 6, and by contacting the side portions of the bump 9 at four contact points CP (see FIG. 2), the force applied per contact point CP can be reduced.
Thereby, the deformation of the bump 9 with time is suppressed, and the necessary pressing force between the bump 9 and the contact portion 5 can be maintained for a long time. Further, even if a foreign substance adheres to one contact plate 6, the other contact plate 6 comes into contact with the bump 9, so that a contact failure is less likely to occur as compared with the related art. Thus, the socket 1 of the present embodiment is
The reliability of the electrical connection with the bumps 9 is improved with respect to entry of foreign substances when the A package 8 is mounted and with respect to factors over time.

In the above example, the case where the position of the bump 9 is shifted from the normal position has been described. On the contrary, the case where the mounting position of the connection terminal 3 with respect to the socket body 2 is shifted is also described. As described above, the contact portion 5 of the connection terminal 3 is displaced following the bump 9 to be displaced.
Accept. Therefore, a good connection between the connection terminals 3 and the bumps 9 can be obtained without strictly defining the positional accuracy of the connection terminals 3, so that the productivity of the socket 1 is improved. In addition, since it is not necessary to strictly define the positional accuracy of the connection terminal 3, the number of inspection steps and the number of management steps at the time of manufacturing the socket 1 can be reduced, so that cost reduction can be achieved.

In this embodiment, an example in which the contact portion 5 is constituted by four contact plates 6 has been described. However, the number of the contact plates 6 is not limited to this, and a plurality of contact plates 6 can be pressed. If so, any number of copies can be made. From the viewpoint of dispersing the force applied to the bumps 9 more, it is preferable that the number of the contact plates 6 is large, but the number of the contact plates 6 may be determined within a range that does not hinder the production of the contact portion 5.

Further, in this embodiment, the example in which each contact plate 6 makes point contact with the bump 9 has been described, but the form of contact with the bump 9 in the contact portion 5 is not limited to point contact. For example, as shown in FIG.
By making the shape of each contact plate 16 such that the area surrounded by them is substantially circular,
Are in line contact with the bumps 19 in the area CA.
Such a form of line contact is also preferable in dispersing the force applied to the bump 19.

[0027]

As described above, according to the present invention, the reliability of the electrical connection with the bumps is improved because each connection terminal has a contact portion sandwiching the side of the bump of the BGA package at a plurality of locations. Can be.

Further, since the contact portion is supported on the bottom surface of the opening of the socket body by a support portion made of a material having elasticity and conductivity, connection can be performed without strictly defining the positional accuracy of each connection terminal. The terminals and the bumps can be electrically connected. As a result, the number of inspection steps and the number of management steps at the time of manufacturing the socket can be reduced, and the productivity of the socket can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a BGA package socket according to an embodiment of the present invention.

FIG. 2 shows one of the connection terminals of the socket shown in FIG.
It is a perspective view shown in the state where the bump of A package was inserted.

FIG. 3 is a diagram for explaining an operation of mounting a BGA package on the socket shown in FIG. 1;

FIG. 4 is a diagram for explaining an operation of mounting a BGA package on the socket shown in FIG. 1;

FIG. 5 is a diagram for explaining an operation of mounting the BGA package on the socket shown in FIG. 1;

FIG. 6 is a perspective view showing another example of the shape of the connection terminal used in the present invention.

FIG. 7 is a perspective view of a conventional socket for a BGA package.

8 is a cross-sectional view showing the socket shown in FIG. 7 with a BGA package mounted.

FIG. 9 is a sectional view showing various forms of connection terminals of the socket shown in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Socket 2 Socket main body 3 Connection terminal 4 Support part 5, 15 Contact part 6, 16 Contact plate 8 BGA package 9, 19 Bump

Claims (6)

[Claims] 1. A BG having a plurality of bumps provided on one main surface.
A socket used to mount the A package on a substrate, comprising: a socket body provided with an opening for accommodating the BGA package; and a bottom surface of the opening of the socket body provided corresponding to each of the bumps. A plurality of connection terminals electrically connected to each of the bumps, wherein each of the connection terminals is made of a conductive material, and the socket body accommodates the BGA package. A BGA package socket having a contact portion that presses the side portion of the bump at a plurality of locations. 2. The BGA package socket according to claim 1, wherein each of the contact portions is composed of a plurality of contact plates for sandwiching a side portion of the bump. 3. The BGA according to claim 2, wherein each of the contact plates is arranged to surround a side portion of the bump when the BGA package is accommodated in the socket body.
Socket for package. 4. The area of a region surrounded by each of said contact plates is:
4. The BGA package socket according to claim 3, wherein the width of the opening increases from the bottom surface of the opening of the socket body toward the opening end. 5. The BGA according to claim 1, wherein the contact portion is supported on a bottom surface of the opening of the socket body by a support portion made of a material having elasticity and conductivity. Socket for package. 6. The BGA package socket according to claim 5, wherein the support is a curved rod-shaped member.