JP2002164135A - Socket - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure of a contact piece with an appropriate contact pressure applicable to an electronic device having terminals with narrowed grid pitch like CSP, and to provide a CSP socket having above structural arrangement. SOLUTION: The socket comprises a lower contact to be connected to a circuit network terminal at lower side, an upper contact contacting with the terminal of an electronic device at upper side, and a thin plate contact piece having an elastic deformation part between two contacts. A plurality of centers of the width of contact pieces are arranged with a suitable angle to the x-axis of xy orthogonal coordinate system, and an appropriate contact pressure is maintained by utilizing the elastic deformation of the material of which the length is longer than the grid pitch by several times. The peripheral part of the contact pieces are surrounded by an electromagnetic wave shielding material in order not to generate cross-talk, and the electromagnetic wave shielding material is enabled to electrically connect with the ground.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a CSP (chip / chip).
The present invention relates to a socket having a semiconductor package (hereinafter, referred to as an electronic device) having terminals of a grid array (lattice arrangement) called a BGA and a contact assembly electrically connected to an external circuit. More particularly, the present invention relates to a contact shape and an arrangement method thereof.

[0002]

2. Description of the Related Art A contact used as a means for electrically connecting a terminal of an electronic device and a terminal of a test circuit at the time of a test requires an elastically deformable portion. The contacts disclosed in JP-A-9-275168 and JP-A-10-3973 have upper and lower electrical contact portions and an arcuate curved portion in the middle. This curved portion deformed at the time of contact, and the restoring force was the contact pressure between the terminals. Such an arcuate curved portion could secure the space of the deformed portion when the pitch between the terminals was large, but the space for the deformed portion became small because the space of the deformed portion became small in order to cope with CSP etc. where the pitch between the terminals was small. It was very difficult to obtain the amount of deformation and the restoring force. Further, in general, the number of types of parts of a contact portion of a contact that comes into contact with a ball solder portion of an electrical connection portion of a CSP is large, and the shape is complicated and expensive.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to cope with an electronic device having terminals whose lattice pitch is reduced by a CSP or the like. An object of the present invention is to provide a socket used for a CSP or the like having a contact that can secure a contact force deformation amount.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, the present invention relates to a method in which a lower contact connected to a test circuit terminal side is provided on the one hand and an electronic device terminal such as a CSP is provided on the other hand. A contact and a thin plate-like contact having an elastically deformable portion between the two contacts, wherein the upper contact is formed by deforming a thin plate material at the tip to effectively contact a solder ball terminal such as a CSP. It has an integral Y-shape when viewed from above.

Further, the contact comprises a thin plate-like contact having an elastically deformable portion between the two contacts, and the contact is xy.
A plurality of elements are arranged at a predetermined angle with respect to the x-axis of the Cartesian coordinate system, and by allowing elastic deformation of a material that is several times as long as the lattice pitch, a suitable contact force and deformation can be secured. I made it.

The invention according to claim 1 of the present invention is characterized in that, on the one hand, a lower contact connected to a circuit terminal, on the other hand, an upper contact that contacts a solder ball or the like of an electronic device terminal under test, In the thin plate contact having an elastic deformation part in the middle, the tip part is formed by deforming the thin plate material in order to enable effective electrical connection to the solder balls of the electronic device terminals under test.
The contact is characterized by being bent in a Y-shape when viewed from the side, and has an operation capable of reducing manufacturing costs.

According to a second aspect of the present invention, there is provided a lower contact which is connected to a circuit element on one side, an upper contact which contacts a solder ball of an electronic device terminal to be tested on the other side, and When the direction in which the solder balls and the like of the electronic device terminals under test are arranged as the x-axis of the xy orthogonal coordinate system, the thin plate-shaped contact having an elastically deformable portion in the middle forms a predetermined angle with the x-axis. A socket characterized by being arranged, which has an effect of enabling a socket with a narrow pitch.

According to a third aspect of the present invention, there is provided a socket wherein a plurality of the contact assemblies according to the second aspect are arranged in the y direction of an xy orthogonal coordinate system, wherein a grid-like solder ball pitch is provided. This has the effect of enabling a socket consisting of contacts arranged in a grid with much longer deformations.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a front view of a contact according to a first embodiment of the present invention, and FIG. 2 is a perspective view of the contact. In FIG. 1, reference numeral 1 denotes a contact having a thin plate-like structure for electrically connecting the circuit under test and the test circuit, 2 denotes a lower contact which is a part of the contact 1 and serves as an input portion that contacts a terminal of the circuit under test,
Reference numeral 3 denotes an upper contact which is electrically connected to a terminal of a test circuit, and reference numeral 4 denotes a deformation which is elastically deformed so that the lower contact 2 and a terminal of a circuit under test come into contact with an appropriate contact force when arranged within a certain positional relationship. Department. Reference numeral 5 denotes a guide sheet, which is drawn in a schematic size corresponding to one contact in FIGS. 1 and 2, but corresponds to a plurality of contacts,
The size should be adapted to that. The guide sheet 5 appropriately holds the contact 1 and maximizes the restoring force of the deformed portion 4 due to the deformation of the deformed portion 4 as a means to act on the terminals of the circuit under test and the solder balls of the socket. It has the function of holding the guide sheet 5 vertically. Contact 1
A lower contact 2 is inserted as shown in FIG. In addition, the sheet guide 5 having the same purpose (not exactly the same shape) can achieve the purpose of accurately guiding the upper contact 3 to the ball terminal, which is the object of the present invention, for guiding the multiple contacts 1.

The contactor 1 of the present invention has high rigidity in the p-direction parallel to the thin plate surface shown in FIG. 2 and soft rigidity in the q-direction. In addition, the deformation of the contact 1 having a soft rigidity in the q direction ensures that a preferable contact force is applied from the upper contact 3 to the ball terminal 8. Contact 3
Can be achieved by bending the thin plate contact 1 and is therefore suitable for mass production processing.
Enable socket for SP.

FIG. 3 is a side view showing the relationship among the contact 1, the ball terminal 8, and the circuit terminal. 7 is a CSP. 8 is C
SP7 ball terminal. Generally, the ball terminals 8 have a spherical shape at the lower portion, and are made of a material having high conductivity such as solder, and are arranged in a plurality in a grid pattern. Further, the contacts 1 of the socket of the present invention are arranged to face the ball terminals 8. 9
Is a printed circuit board, and 10 is a circuit terminal. The purpose of the contact 1 is to electrically and stably connect the circuit terminal 10 and the ball terminal 8 via the contact 1.

When the connection between the circuit terminal 10 and the ball terminal 8 is performed, the CSP 7 is pushed down in the direction of arrow A. After the lower contact 2 of the contact 1 comes into contact with the circuit terminal 10 and the upper contact 3 comes into contact with the ball terminal 8 and the CSP 7 is further pushed down in the direction of arrow A, the deformed portion 4 is deformed and the restoring force is reduced. 3, through the lower contact 2, it comes into contact with the ball terminal 8;
Has a Y-shape, a stable contact is maintained because no force acts so that the spherical portion of the upper contact 3 and the ball terminal 8 escapes outside the Y-shape, and electrical connection is ensured.

FIG. 4 is a diagram showing an example in which a plurality of contacts 1 are arranged in one row in the x-axis direction of an xy orthogonal coordinate system in correspondence with ball terminals 8 arranged in a grid. Where x-axis, y
The axes and the xy orthogonal coordinate system are directions perpendicular to each other in the row and column directions of the grid so as to be a reference when arranging the ball terminals 8 in a grid on a plane (such as a substrate surface of an IC board or the like). , And the coordinate system specified by these axes. In FIG. 4, a plurality of upper contacts 3 are arranged at equal intervals in the x-axis direction. A ball terminal 8 (not shown) of the CSP 7 is connected to the upper contact 3.
Correspond, and both touch. Moreover, the arrangement direction of the contact 1 is x
It is set so as to be inclined with respect to the x-axis so as to form a predetermined angle α with the axis. This enables the width of the contact 1 to be larger than the arrangement pitch of the upper contacts 3 without interfering with the adjacent contact 1.

FIG. 5 shows a plurality of contact assemblies arranged in the x-axis direction corresponding to the ball terminals 8 arranged in a lattice as shown in FIG. FIG. 8 is a plan view in which a plurality of rows are arranged in the y-axis direction so as to correspond to FIG.

As shown in FIGS. 4 and 5, the arrangement direction of the contacts 1 of the contact assembly is set so as to be inclined with respect to the x-axis so as to form a predetermined angle α with the x-axis. The meaning is explained.

4 and 5, since a plurality of contacts 1 are arranged, a plurality of lower contacts 2 and upper contacts 3 are naturally arranged. Since only the upper contact 3 is shown in FIGS. 4 and 5, only the upper contact 3 will be described below. The upper contacts 3 are respectively arranged in the x-axis direction and the y-axis direction on xy orthogonal coordinates. For convenience of description, it is assumed that the upper contacts 3 are arranged at a pitch Po in both the x-axis direction and the y-axis direction. This pitch Po is also the pitch of the ball terminals 8 arranged in a lattice.

In FIGS. 4 and 5, the next (another) contact 1 is arranged adjacent to one contact 1 arranged at an angle α to the x-axis in the longitudinal direction. The next contact 1 is also arranged in the forward direction, ...
The plurality of contacts 1 are arranged in the lattice plane on which the ball terminals 8 are arranged without interfering with each other. However, in practice, it is preferable to leave a slight gap between the above-mentioned one contact 1 and the next contact 1 following it. The reason is that when the contact 1 is elastically deformed by receiving an external force in the vertical direction, its overall length (FIGS. 4 and 5)
This is because there is a possibility that the longitudinal dimension (as viewed in a plan view) may increase or decrease, and if there is no gap, the contacts 1 may interfere with each other. In this specification, a dimension taking into account the increase or decrease in the overall length is defined as a critical dimension.

In the present invention, if L is a limit dimension allowable as the overall length of the contact 1, if Lsinα <Po is satisfied, the arrangement in the y direction can be performed without interference between the contacts 1. Is possible.

In this embodiment, by arranging the contacts 1 while satisfying the above conditions, the plurality of contacts 1 fill the grid plane on which the ball terminals 8 are arranged, and They are arranged without interfering with each other. That is, in order to arrange the upper contact 3 in the x-axis direction and the y-axis direction on the xy orthogonal coordinates, the angle α is such that the contact 1 itself having the thin plate-like structure is positioned with respect to the x-axis on the xy orthogonal coordinates. It is shown that they are arranged inclined by the angle α.

In this way, the grid area, which is the area in which the upper contact 3 is arranged, (which is also the area in which the ball terminals 8, which are a plurality of terminals of the electronic device, are arranged in a grid) is used using substantially the entire area. That is, the contacts are arranged (that is, so as to fill the lattice area). Thus, even if the degree of integration of the integrated circuit is increased and the circuit network is extremely miniaturized, the connection between the upper contact 3 and the ball terminal 8 can be effectively performed by using a small area,
A socket having the upper contacts 3 facing the ball terminals 8 arranged in a lattice is made possible.

The reason why the contacts 1 are arranged at an angle of α with the x-axis is to secure a deformed portion longer than the lattice pitch Po while avoiding interference with adjacent contacts. In this way, by securing the deformed portion as long as possible in the contact 1, an appropriate elastic coefficient can be given to the contact 1. It is desirable that the dimension of the contact 1 in the thickness direction be much smaller than the pitch Po. However, at present, even when the pitch Po of the wafer terminals related to the wafer burn-in test corresponds to about 150 μm, the thickness is 10 μm. Since materials such as iron-based spring steel of about 20 μm are also commercially available, contact 1
There is no restriction from the material. It is clear that if a thick material of Po / N (N is a positive number) is used for the contact 1, a contact having an S larger than the pitch Po can be obtained.

[0022]

According to the present invention, as is apparent from the above-described embodiment, the contact which enables stable electric conduction with the spherical ball terminal by bending or the like of a thin plate material is fixed to the x-axis by a predetermined distance. By arranging a plurality of sockets at an angle of, it is possible to provide an inexpensive socket that can be applied to an electronic device test such as a CSP having terminals of a narrow pitch line and a grid array.

[Brief description of the drawings]

FIG. 1 is a front view of a contact according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a contact according to the first embodiment.

FIG. 3 is a side view showing a relationship between a contact, a ball terminal and a circuit terminal of the CSP.

FIG. 4 shows a plurality of contacts in the x-axis direction of an xy orthogonal coordinate system,
FIG. 3 is a plan view in which rows are arranged.

FIG. 5 is a plan view in which a plurality of contact assemblies shown in FIG. 4 arranged in the x-axis direction are arranged in a plurality of rows in the y-direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Contact 2 Lower contact 3 Upper contact 4 Deformation part 5 Guide sheet 6 Hole 7 CSP 8 Ball terminal 9 Printed circuit board 10 Circuit terminal

Claims (3)

[Claims] 1. A thin contact having an elastically deformable portion between one of a lower contact connected to a circuit terminal on one side, an upper contact in contact with a solder ball of an electronic device terminal under test on the other side, and a contact between the two contacts. In order to enable effective electrical connection to the solder balls of the terminals of the electronic device under test, the tip is formed by deforming a thin sheet material and bent into a Y-shape when viewed from the side. Contact. 2. A thin contact having an elastic contact on one side of a lower contact connected to a circuit element, an upper contact on the other hand in contact with a solder ball of an electronic device terminal under test, and an elastically deformable portion between the two contacts. Is the direction in which the solder balls and the like of the electronic device terminals under test are arranged.
A socket characterized by being arranged at a predetermined angle with respect to the x-axis in the y-axis coordinate system. 3. A plurality of thin plate-shaped contacts are arranged in the x-axis and y-axis directions of an xy orthogonal coordinate system.
The described socket.