JPH06230032A - Probe base plate - Google Patents

Abstract

PURPOSE:To stabilize the pressure of a probe against an object to be inspected and the durability of the probe, eliminate slip of the extreme end of the probe on the object to be inspected, and easily attain the small pitch trend of the probe. CONSTITUTION:A probe 4 is formed into a narrow plate shape, the extreme end 4a is formed into a bent shape such as V-shape or U-shape, and when the extreme end is pressed against an object 8 to be inspected, the direction of deflection is set so as to conform to the pressing direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a probe substrate used for inspecting integrated circuit chips in the manufacturing process of large scale semiconductor integrated circuits (LSI).

[0002]

2. Description of the Related Art A probe board of this type is generally circular or substantially square, and a large number of probes are provided on a lower surface of a central portion of a printed board having a through hole via an annular probe supporting member made of ceramic or aluminum. Is fixed by molding an insulating material or the like so that its tip faces downward.

FIG. 7 is a sectional view showing an example of a conventional probe substrate, and each is shown as a sectional view including a probe.

In the sectional view of FIG. 7A, the conventional probe substrate 21 is shown as a right half sectional view from the center. In the probe substrate 21, the probe 22 has a tip 22a.
The probe 22 is formed in a taper shape so that its diameter becomes gradually smaller as it gets closer to, and the entire probe 22 is oblique with respect to the substrate 23 of the probe substrate 21 (generally, an angle of about 10 degrees with respect to the surface of the substrate 23). It is fixed to the insulating material 24 by molding or the like, and the insulating material 24 is fixed to the lower surface of the central portion of the substrate 23 via the probe supporting member 25. The probe supporting member 25 is formed of ceramic, aluminum, or the like, and also functions as a spacer.

The tip 22a of the probe 22 is bent near the tip 22a so that the tip 22a is oriented in a substantially vertical direction when the substrate 23 is placed horizontally.

Further, the probe substrate 26 shown in FIG.
Then, the probe 27 is fixed at right angles to the substrate 28, so that when the substrate 28 is placed horizontally, the probe 27 is fixed to the insulating material 29 by molding or the like so that all of the probes 27 face the vertical direction. Support member 30
It is fixed to the substrate 28 via.

In the inspection of the semiconductor integrated circuit, when the inspection table 32 on which the integrated circuit chip 31 is placed is raised from below toward the probe substrate 21, the tip 22a of the probe 22 is brought into contact with the pad 33 of the semiconductor integrated circuit to be inspected. Contact each other.

[0008]

[Problems to be Solved by the Invention] By the way, the progress of the degree of integration of semiconductor integrated circuits has been remarkable in recent years, and the density of integrated circuit chips is becoming more and more remarkable in combination with the use in small precision equipment such as cameras. Has become. With the increase in the density of this integrated circuit chip, not only the pads are downsized, but the pitch between adjacent pads is also reduced.
It is expected to be 0 μm and 50 μm. Therefore, also in the probe substrate, it is necessary to have a structure in which the pitch of the probes is matched with the pitch of the pads.

However, in the probe substrate as described above, there is a limit (around 150 μm is a limit) in positioning the probe to a small pitch due to the difficulty of positioning, and for example, a height of 100 μm or 50 μm is high. It has been impossible to deal with a semiconductor integrated circuit having a densified integrated circuit chip.

If the pad pitch is 150 μm,
Even if it is possible to construct a probe board having a limit probe pitch of about 150 μm, which corresponds to a semiconductor integrated circuit to be inspected, the diameter (thickness) of the probe at this time is extremely small (thin). , Needle pressure and durability will be a problem. Straightness (keep the probe straight)
However, there is a new problem that the positioning with the pad cannot be performed easily. Furthermore, since the bent portion on the tip side of the probe also becomes thin, it is expected that the problem of unstable contact with the pad will occur.

7A, when the tip 22a of the probe 22 contacts the pad 33 of the integrated circuit chip 31, the tip 22a of the probe 22 slightly moves over the pad 33, as shown in FIG. slide. This improves the contact between the tip 22a of the probe 22 and the pad 33. However, when the pad 33 is miniaturized as described above, the inspection table 32 on which the integrated circuit chip 31 is mounted when the semiconductor integrated circuit is inspected is transferred to the probe substrate 21. If the tip 22a of the probe 22 rises too much, the tip 22a of the probe 22 slips too much and comes off the pad 33.

(Object of the Invention) The object of the present invention is to stabilize the pressure of the probe against the object to be inspected and the durability of the probe, and to eliminate the slip of the tip of the probe on the object to be inspected. Moreover, it is an object of the present invention to provide a probe substrate that can easily reduce the pitch of the probe.

[0013]

According to the present invention, a tip end of a probe that comes into contact with an object to be inspected is formed into a bent shape in which a plate-like elastic material is folded in two, and both ends are fixed to a probe supporting member ( The probes are arranged side by side at a predetermined pitch in the width direction.

[0014]

According to the present invention, the probe is formed into a narrow plate shape and the tip is bent substantially in two to form a bent shape, and both ends of the probe are fixed to the probe supporting member. Alternatively, it is formed in a U shape so that when the tip end is pressed by the object to be inspected, the bending direction thereof matches the pressing direction.

[0015]

1 and 2 are external views of a probe substrate according to an embodiment of the present invention. FIG. 1 is a perspective view and FIG.
It is the side view seen from the arrow B direction in. Also, FIG.
1 is a sectional view taken along the line AA 'in FIG. 1, and FIG. 4 is a partially enlarged perspective view of FIG.

The probe substrate 1 is a rod-shaped probe made of an insulating material (resin), which holds a large number of narrow plate-shaped probes 4 on the upper surface of an elongated hole 3 formed near the center of the printed circuit board 2. The support member 5 is the tip 4 of the probe 4.
a is fixed so that the printed circuit board 2 faces downward.

The probe 4 is made of, for example, tungsten, has a tip 4a bent in a V shape, and both ends thereof are fixed to opposite side surfaces of the probe supporting member 5 with an adhesive. The intervals between the multiple probes 4 are determined so that the probes 4 are arranged at a predetermined pitch in the width direction. In addition, one end of the probe support member 5
It is extended from the upper surface of and is used as the signal extracting portion 4b. As shown by the dotted line in FIG. 3, the signal take-out portions 4b are soldered to one terminals 6a of the printed pattern 6 formed on the upper surface of the printed circuit board 2, and the printed pattern 6 causes the printed circuit board 2 to be printed. It is pulled out to the outer peripheral side (see FIG. 1), and is connected to the ground and power source, electronic circuit parts, inspection device, etc. through the other terminal 6b.

By making the tip 4a of the probe 4 V-shaped as described above, the pad 8 of the integrated circuit chip 7 which is the device under test is pressed against the tip 4a of the probe 4 so that the integrated circuit chip 7 is pressed. The inspection table 9 on which is mounted is shown in FIG.
When raised from the state of (a), as shown in FIG. 5 (b), since the bending direction is only the direction of arrow a, the probe 4 does not slip off from the pad 8. .

The pressure of the probe 4 [the force that opposes the force indicated by the arrow a in FIG. 5 (b)] is held by the width (length in the direction in which the probes 4 are arranged) and length (the probe supporting member 5). 4). As is clear from FIG. 4 and the like, the probe 4 in this embodiment has a narrow, so-called plate shape, and the probe supporting member 5 has Since the distance from the held portion to the tip 4a can be adjusted freely, it becomes much more rigid than the conventional probe having a fine diameter, and the pressure can be stabilized. Further, from this, the durability can be improved.

Further, since the tip 4a of the probe 4 does not bend in the direction of the adjacent probe 4, positioning of the tip 4a can be facilitated and the pitch between the probes can be reduced.

(Second Embodiment) FIG. 6 is a sectional view (corresponding to FIG. 2) of a main portion of a probe substrate according to another embodiment of the present invention. The same reference numerals are given and the details thereof are omitted.

In the second embodiment, the method for connecting the signal extracting portion 4b of the probe 4 and the printed circuit board is the same as the first embodiment described above.
2 shows the structure when different from the embodiment of FIG.

A probe supporting member 5 holding a large number of probes 4 is fixed to an insulating plate 10 having an elongated hole 10a,
The insulating plate 10 is an insulating member 1 that functions as a spacer.
Printed circuit board 1 having through hole 13 through 1
Fixed to 2.

The signal extracting portion 4b of the probe 4 is soldered to each of the printed patterns 14 through the through holes 13 which also serve as terminals covered with the conductive member of the printed circuit board 12. It is pulled out to the outer peripheral side of the substrate 12 and connected to a ground and a power source, electronic circuit parts, inspection equipment, and the like.

(Modification) Probe 4 in this embodiment
Although tungsten is assumed as the material, the material is not particularly limited as long as it has elasticity and can be plated with gold or nickel.

As the probe 4, it is also possible to use a conductive material such as copper having a relatively low rigidity. In this case, it may be necessary to attach (interpose) a film between the probe 4 and the probe supporting member 5 to increase its rigidity. At this time, the film is attached by the probe 4
May be attached to only one end side (for example, the signal extraction portion 4b side) or both end sides.

Although the probe 4 has a V-shape, it is not limited to this, and a U-shape or the like may be used.
Any elastic plate-shaped elastic material may be used as long as it has a bent shape formed by folding the elastic material into substantially two folds.

[0028]

As described above, according to the present invention,
The probe is formed into a thin plate shape, and the tip thereof is folded in two, so that the probe has a bent shape, for example, a V shape or a U shape.
It is formed in a character shape, and when the tip end is pressed by the object to be inspected, the bending direction thereof is made to coincide with the pressing direction.

Therefore, the pressure of the probe against the object to be inspected and the durability of the probe are stabilized, the tip of the probe is prevented from slipping on the object to be inspected, and the probe pitch can be easily reduced. It becomes possible to do.

[Brief description of drawings]

FIG. 1 is a perspective view of a probe substrate according to an embodiment of the present invention.

FIG. 2 is a side view seen from the direction of arrow B in FIG.

3 is a cross-sectional view taken along the line AA ′ of FIG.

FIG. 4 is a partially enlarged perspective view of FIG.

FIG. 5 is a cross-sectional view showing a state before and after a pad is pressed against a probe in one embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a main part of a probe substrate according to another embodiment of the present invention.

FIG. 7 is a cross-sectional view showing an example of a conventional probe substrate.

FIG. 8 is a diagram showing a movement of a probe on a conventional probe substrate.

[Explanation of symbols]

 1 Probe Board 2 Printed Circuit Board 4 Probe 4a Tip 4b Signal Extraction Section 5 Probe Support Member 7 Integrated Circuit Chip 8 Pad 10 Insulation Plate 11 Insulation Member 12 Printed Circuit Board

Claims (1)

[Claims] 1. A large number of electrically conductive probes, each of which has a tip for abutting against an object to be inspected, the end of which is connected to a printed pattern on a printed circuit board, or directly on the printed circuit board.
In a probe board that is indirectly fixed and that includes a probe supporting member that holds the large number of probes at a predetermined pitch, the probe is formed by folding a narrow plate-like elastic material into substantially two folds and bending the tip thereof. A probe substrate, which is formed in a shape and whose both ends are fixed to the probe supporting member.