JPH11142474A - Auxiliary device for testing flat plate-like inspected body and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an auxiliary device not changing the height size and apex shape of bump electrodes by forming multiple conductive lugs at intervals on one face of an insulating substrate, and forming recesses having the same cross sectional area from the top faces to the prescribed depth on the top faces of the lugs parallel with the substrate. SOLUTION: An IC chip 12 is provided with multiple bump electrodes 16 on a flat plate-like device main body 14, and the bump electrodes 16 are formed into a semispherical shape by soldering on electrodes 18. An auxiliary device 10 is provided with conductive through holes 22 formed on an insulating substrate 20, first lugs 24 and second lugs 26. The lugs 24, 26 closing the through holes 22 are integrated by connecting members 28 made of the same material and are electrically connected. Each lug 24 has a hemispherical shape with a top face 30 parallel with the substrate 20, each lug 26 has a hemispherical shape and each member 28 has a cylindrical shape. Each top face 30 has a recess 32, and the recess 32 has a cross sectional area and a cross sectional shape to the prescribed depth position. The lugs 24 and the electrodes 16 are pressed to each other during a test.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an auxiliary device used for a current test of a flat test object such as an integrated circuit.

[0002]

2. Description of the Related Art In general, an integrated circuit chip (IC chip) such as a flip chip has a large number of electrodes (terminals) on one surface, and the electrodes are stacked on a circuit board such as a wiring board. Is connected to an electrode of the circuit board (that is, a pad electrode). Each electrode of the IC chip is a hemispherical protrusion (that is, a bump electrode) formed by solder, and is electrically connected to the pad electrode by being heated while being in contact with the pad electrode of the circuit board. You.

[0003] An IC chip of this type is subjected to a conduction test before being placed on a circuit board in order to inspect its quality.
In general, this type of IC chip energization test is performed using an auxiliary device having a plurality of protrusions formed on a substrate, instead of a needle type probe card.

[0004] One type of auxiliary device is one in which a large number of protrusions are densely arranged on a substrate such that their tips are randomly or in a matrix like the bump electrodes of an integrated circuit chip. (Japanese Unexamined Patent Application Publication No. Hei 8-327659)
No.).

In this auxiliary device, each projection has a recess opening toward the IC chip, and the recess of each projection has a cross-sectional area that becomes smaller toward the substrate. During the energization test, each protrusion
It is pressed by the bump electrode of the IC chip. As a result, the top of each bump electrode made of solder bites into the recess of the projection.

In the above auxiliary device, since the cross-sectional area of the recess of each projection becomes smaller toward the substrate, the base of the bump electrode (the part on the device body side) is deformed so as to be crushed by the device body side. At the same time, the bump electrode is deformed such that the top portion is crushed toward the axis (the center of the recess). Of such deformations of the bump electrode, deformation of the base causes the base to bulge, but does not affect the height dimension and the top shape of the bump electrode.

However, when the top of the bump electrode is crushed toward its axis, the top of the bump electrode is pushed and stretched, so that the height of the bump electrode becomes irregularly large and the shape of the top of the bump electrode is changed. Deform irregularly. As described above, when the height of the bump electrode or the shape of the top portion is irregularly changed, when the IC chip is mounted on the circuit board,
There are bump electrodes that do not contact the pad electrodes of the circuit board, resulting in improper connection to the circuit board.

[0008]

Therefore, it is important to provide an auxiliary device which does not change the height and the shape of the top of the bump electrode.

[0009]

An auxiliary device according to the present invention includes an electrically insulating substrate and a plurality of conductive projections formed on one surface of the substrate at intervals. Each projection has a top surface that is substantially parallel to the substrate and has a recess that opens into the top surface. Each recess has approximately the same cross-sectional area from the top surface to a predetermined depth.

When each projection is pressed against the bump electrode of the IC chip, the top of the bump electrode is received in the recess of the projection. However, when the recess of each projection has substantially the same cross-sectional area from the top surface to a predetermined depth, the force of crushing the base of the bump electrode toward the device body acts on the bump electrode,
The force that crushes the top toward its axis does not act on the bump electrode. For this reason, the auxiliary device of the present invention does not change the height dimension and the top shape of the bump electrode.

A plurality of conductive through holes penetrating the substrate in the thickness direction may be formed in the substrate, and each through hole may be closed at least at one end by a projection. Further, a hemispherical second projection for closing each through hole at least at the other end may be formed on the other surface of the substrate.

[0012] In a preferred embodiment, the recess has the same cross-sectional shape at portions between constant cross-sectional areas. Also, each protrusion may have a plate-like shape, but in a preferred embodiment has a truncated hemispherical shape with the top removed substantially parallel to the substrate.

In the auxiliary device as described above, a plurality of conductive protrusions are formed at intervals on one surface of an electrically insulating substrate, and the top of each protrusion is removed substantially in parallel with the substrate. Can be manufactured by forming a recess in each projection that is open to the top surface and has substantially the same cross-sectional area from the top surface to a predetermined depth position.

Further, before forming the projections, a plurality of conductive through holes penetrating the substrate in the thickness direction are formed in the substrate, and then each projection is formed so as to close the through holes at at least one end. Can be. Furthermore, a hemispherical second projection that closes each through hole at least at the other end can be formed on the other surface of the substrate. The recess can be formed into a circular shape having the same cross-sectional area and cross-sectional shape by drilling.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 to 3, an auxiliary device 10 is used for an energization test of an IC chip 12. FIG.
The IC chip 12 includes a plurality of bump electrodes 1 provided randomly or in a matrix on a flat device body 14.
6. Each bump electrode 16 is formed in a hemispherical shape by soldering on an electrode 18 provided on one surface of the device body 14.

The auxiliary device 10 comprises an electrically insulating substrate 20
A plurality of conductive through holes 22 formed randomly or in a matrix on the substrate;
2 is provided with a first projection 24 closing one end thereof, and a second projection 26 closing each through hole 22 at the other end.

The substrate 20 is formed of a synthetic resin material such as polyimide, and has flexibility or rigidity. The through holes 22 are formed in a pattern corresponding to the arrangement pattern of the bump electrodes 16 of the IC chip 12 by using a conductive material. First and second projections 24 and 2
6 is formed from a conductive material such as nickel.

The first and second projections 24 and 26 closing the same through-hole 22 are provided with corresponding through-holes 22.
It is integrated by a connecting member 28 made of the same material provided therein, and is therefore electrically connected by the through hole 22 and the connecting member 28. The connecting member 28 may not be provided.

Each first protrusion 24 has a truncated hemispherical shape having a top surface 30 substantially parallel to the substrate 20, each second protrusion 26 has a hemispherical shape, and each connecting member 28 Has a columnar shape. Each first projection 24 has a recess 32 that opens into the top surface 30.

Each recess 32 has substantially the same cross-sectional area and cross-sectional shape from the top surface 30 to a predetermined depth position.
Such a recess 32 can be formed by drilling from the side of the top surface 30. In the example shown, each recess 3
2 has a circular cross-sectional shape, but may have a polygonal cross-sectional shape. Note that the cross section refers to a plane perpendicular to the axis 34 of the projection 24.

At the time of the power-on test, the auxiliary device 10 and the IC chip 12 are relatively displaced in the mutually approaching direction in a state where one of them is disposed above the other, so that The bump electrode 16 is pressed. At this time, each bump electrode 16 made of solder is deformed such that its base is crushed toward the device body 14 and its top bites into the recess 32 of the projection 24.

As a result, the base of the bump electrode 16 is deformed so as to be crushed toward the device body 14, and a step is formed near the boundary between the base and the top of the bump electrode 16. These deformations cause the base of the bump electrode 16 to bulge, but do not affect the height dimension and the shape of the top of the bump electrode 16.

If the cross-sectional area and cross-sectional shape of each recess 32 are substantially the same up to a predetermined depth position, even if the top of the bump electrode 16 bites into the recess 32, the top of the bump electrode 16 is The force for squeezing to the side does not act on the bump electrode 16. For this reason, the auxiliary device 10
Even if the bump electrode 16 and the projection 24 are pressed, the height dimension and the shape of the top of the bump electrode 16 are not changed. This is true even if the cross-sectional area is slightly different.

The auxiliary device 10, for example, first forms a plurality of through holes 22 in a rigid resin substrate 20 in the same pattern as the bump electrodes 16 of the IC chip 12 to be inspected. The protrusions 24 and 26 and the member 28 are formed in each through hole 22 by an appropriate method such as a vapor phase growth method, and then the top of each first protrusion 24 is cut out substantially parallel to the substrate 20 to form the top surface 30. After that, each projection 24 is drilled from the side of the top surface 30 to form the recess 3.
2 can be manufactured. Therefore, the auxiliary device can be easily manufactured.

Since the auxiliary device 10 has a plurality of projections 24, it can be used as a projection type probe card. For this reason, the auxiliary device of the present invention is not only an auxiliary device for conducting a current test of an IC chip directly mounted on a circuit board, but also for conducting a current test of another flat inspected pair such as another integrated circuit or a liquid crystal display panel. It can also be applied to auxiliary devices.

The present invention is not limited to the above embodiment. For example, the shape of each first projection 24 may be plate-shaped instead of being truncated hemisphere. Further, the through hole 22 and the second protrusion 26 may not be provided. Further, the substrate 2
0, a plurality of wiring portions are formed, and each of the wiring portions has a first protrusion 24.
May be formed.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of an auxiliary device of the present invention and an IC chip to be tested.

FIG. 2 is an enlarged cross-sectional view near a first protrusion and near a bump electrode.

FIG. 3 is a plan view of a first protrusion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Auxiliary device 12 IC chip 16 Bump electrode 20 Substrate 22 Through-hole 24 First projection 26 Second projection 30 Top surface of projection 32 Depression of projection

Claims (6)

[Claims] 1. An electronic device comprising: an electrically insulating substrate; and a plurality of conductive protrusions formed on one surface of the substrate at intervals, each protrusion having a top surface substantially parallel to the substrate. In addition, an auxiliary device for testing a flat object to be inspected has concave portions opened to the top surface, and each concave portion has substantially the same cross-sectional area from the top surface to a predetermined depth position. 2. The auxiliary device according to claim 1, further comprising a plurality of conductive through holes penetrating the substrate in a thickness direction, wherein each of the through holes is closed at least at one end by the protrusion. 3. The auxiliary device according to claim 2, further comprising a hemispherical second protrusion formed on the other surface of the substrate and closing each through hole at at least the other end. 4. A plurality of conductive protrusions are formed at intervals on one surface of an electrically insulating substrate, the tops of the protrusions are removed substantially parallel to the substrate, and open to the top surfaces of the protrusions. And forming a recess having substantially the same cross-sectional area in each projection from the top surface to a predetermined depth position. 5. The method according to claim 1, further comprising: forming a plurality of conductive through-holes through the substrate in a thickness direction of the substrate before forming the protrusion, wherein the protrusion has at least one end formed with the through-hole. The manufacturing method according to claim 4, which is formed so as to be closed in the step (c). 6. The manufacturing method according to claim 5, further comprising forming, on the other surface of the substrate, a hemispherical second projection that closes each through hole at least at the other end.