JPH09304433A - Probe equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability, reduce measurement error, and prevent damage of IC chip, by making the sectional area of the tip part of a probe corresponding to a bonding pad for a power source larger than the sectional area of the tip part of other probe. SOLUTION: A chuck top 14 continuously performs reciprocating motion with a specified stroke, at the position where each bonding pad 13 of a semiconductor chip 12 is made to face the tip of each probe 15. When the tip of the probe 15 comes into contact with the bonding pad 13, an electric measurement equipment is brought into contact with the semiconductor chip 12, and electric characteristics test is performed. In order to reduce wear of a probe 15a corresponding to bonding pad 13a for a power source, the cross-sectional area of the tip part 19 of the probe 15a is set larger than the tip part of other probe 15b. Thereby durability of a probe is increased, error due to nonuniformity of length is not generated, and damage of a semiconductor chip can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe device suitable for use in an electrical characteristic test of an IC chip formed on a semiconductor wafer.

[0002]

2. Description of the Related Art In the process of manufacturing a semiconductor IC, generally,
Prior to dicing for separating a large number of IC chips formed on a semiconductor wafer, an electric characteristic test is performed on each IC chip. The probe device used for this electrical characteristic test includes a large number of probes supported by a probe card. Each probe is connected to a measuring device via a connection terminal provided on the probe card, and converges obliquely downward toward the IC chip of the semiconductor wafer arranged on the chuck below the central portion of the probe card. . The IC chip of the wafer arranged on the chuck is pressed against the tip of each probe corresponding to the bonding pad formed on the IC chip as the chuck moves up.

At this time, in order to obtain reliable electrical contact between each probe and the corresponding bonding pad of the IC chip, the tip of the probe angularly extending to the bonding pad slides slightly on the bonding pad. I
The C-tip is pressed entirely onto the probe. Therefore, when the test is repeated tens of thousands of times a day, each probe wears due to the sliding motion of its tip. This wear
If all the probes are substantially uniform, it is possible to ensure reliable electrical contact between each probe and the corresponding bonding pad by correction such as correcting the rising position of the chuck according to the progress of wear. .

[0004]

However, of the bonding pads, the power supply bonding pad is more robust than other signal bonding pads because a larger current flows than other signal bonding pads. Is formed in. Therefore, all the probes do not wear evenly, and the probe corresponding to the power supply bonding pad whose shape or strength is different from that of the other signal bonding pads is particularly worn as compared with the other probes. . Therefore, the length of the probe becomes uneven, so if you set the chuck rising position according to a long probe with less wear, the electrical contact of the short probe with severe wear corresponding to the power supply bonding pad may cause a measurement error. Errors are likely to occur. On the contrary, when the chuck rising position is set in accordance with a short probe with severe wear, a long probe is strongly pressed, which may damage the IC chip. For this reason, there has been a demand for a probe device that has excellent durability, does not cause a measurement error, and does not damage the IC chip.

[0005]

The present invention adopts the following constitution in order to solve the above points. <Structure> The present invention provides a plurality of probes, each tip of which is pressed and connected to a corresponding bonding pad for an electrical characteristic test of a semiconductor chip provided with a plurality of bonding pads including a power supply bonding pad. In the probe apparatus including the above, the cross-sectional area of the tip portion of the probe, which corresponds to the power supply bonding pad and is severely worn, is made larger than that of the tip portion of the other probe corresponding to the other bonding pad.

<Operation> In the probe device according to the present invention,
The cross-sectional area at the tip of the probe corresponding to the power supply bonding pad is set larger than the cross-sectional area at the tip of another probe. Therefore, when the semiconductor chip that is the object to be measured is entirely pressed against the probe, the surface pressure received by the probe corresponding to the power supply bonding pad from this pad can be reduced. By reducing the surface pressure, it is possible to reduce the wear of the tip portion of the probe, which easily wears, corresponding to the power supply bonding pad. Therefore, by appropriately selecting the cross-sectional area at the tip portion of the probe corresponding to the bonding pad for power supply, it becomes possible to make the degree of wear of this probe substantially equal to the degree of wear of other probes,
This makes it possible to suppress uneven wear between the probes and prevent uneven lengths of the probes.

The present invention will be described below with reference to the illustrated embodiments. <Specific Example> FIGS. 1 to 3 show a first probe of the present invention.
[Fig. 4] Fig. 4 is a partially enlarged view showing a part of each of the third specific examples in an enlarged manner. Prior to the description along these drawings, an outline of a probe device incorporating a probe according to the present invention is shown in Fig. 4 and A description will be given with reference to FIG.

4 and 5 are a plan view and a sectional view, respectively, schematically showing a probe device 10 provided with a probe according to the present invention. The probe device 10 is used for an electrical characteristic test of a semiconductor chip 12 such as an IC chip formed on a semiconductor wafer 11, for example. Semiconductor wafer 11 including semiconductor chip 12 to be subjected to electrical characteristic test
As shown in FIG. 4, a plurality of bonding pads 13 (13a) formed on the peripheral portion of the semiconductor chip 12 are provided.
And 13b) with the chuck top 14
Placed on top. Of the bonding pads 13 (13a and 13b), the bonding pad 13a arranged at the corner of the semiconductor chip 12 is a power supply pad,
Compared to the other bonding pads 13b for signals, it is formed relatively robust so as to withstand a large current.

The probe device 10 chucks each probe 15 with a plurality of probes 15 (15a and 15b) made of a metal such as tungsten provided corresponding to the bonding pads 13 (13a and 13b) of the semiconductor chip 12. And a probe card 16 made of an electrical insulator for holding above the semiconductor chip 12 placed on the top 14.

The probe card 16 is fixedly supported above the chuck top 14 by a frame (not shown), and the probe card 16 has connection pins 17 connected to connection terminals of an electric measuring device (not shown). It is provided. The base end portion of each probe 15 is connected to the corresponding connection pin 17, and each probe 15 is connected to the semiconductor chip 1 disposed below the central portion of the probe card 16.
Convergently extend diagonally downward, towards the respective two respective bonding pads 13, as clearly shown in FIG.

The chuck top 14 is the semiconductor chip 12.
At a position where each of the bonding pads 13 is opposed to the tip of each probe 15, the bonding pad 13 is raised by a predetermined stroke. By the rise of the chuck top 14, each bonding pad 13 is pressed against the tip of the probe 15 corresponding to each, and the electrical contact between each probe 15 and the bonding pad 13 corresponding to this probe 15 is obtained.

By contacting the tip of the probe 15 with the bonding pad 13, the electrical measuring device is connected to the semiconductor chip 12 via the probe 15, and the electrical characteristic test of the semiconductor chip 12 is performed. After this electrical characteristic test, the chuck top 14 descends, and the chuck top 14 continuously reciprocates with a predetermined stroke as described above for the subsequent electrical characteristic test of the other semiconductor chips 12. With this reciprocating movement, every time the tip of the probe 15 is pressed relatively to the corresponding bonding pad 13, the tip of the probe 15 that angularly contacts the bonding pad 13 slides slightly on the corresponding bonding pad 13. Move.

By this sliding, the probe 15a corresponding to the power supply bonding pad 13a formed more robustly than the other bonding pad 13b is replaced by the other probe 1
5B, the cross-sectional area of the tip portion of the probe 15a corresponding to the power supply bonding pad 13a is reduced in order to reduce the wear of the probe 15a corresponding to the power supply bonding pad 13a. Is set to be larger than that of the other probe 15b.

FIG. 1 shows a power source bonding pad 13a.
1 shows an enlarged end portion of the probe 15a corresponding to
It is a partial enlarged view about a specific example. The probe 15a shown in FIG. 1 has a tilted body portion 18 with a diameter d.
Is provided with a tip portion 19 continuous with the. The tip portion 19 extends downward at an angle θ with respect to the inclined body portion 18 and is attributed to the lower end that abuts the power supply bonding pad 13a.

The tip portion 19 of the probe 15a has a diameter 1.5d which is, for example, 1.5 times the diameter d of the inclined body portion 18. On the other hand, as shown by the broken line in FIG. 1, the tip portion 19 * of the other probe 15b has a diameter d equal to the diameter of the inclined body portion 18. As a result, the probe 15
The tip portion 19 of a is the tip portion 1 of the other probe 15b.
It has more than twice the cross-sectional area than in 9 *.

The cross-sectional area of the tip portion 19 is another probe 1.
In the probe 15a increased from 5b, the tip portion 1
The surface pressure that the end face 9 receives from the corresponding power supply bonding pad 13 is reduced in accordance with the increase in the area. Therefore, the probe 15a corresponding to the power source bonding pad 13a does not suffer from the severe wear as conventionally seen, and the probe 15a wears with the same degree of wear as the other probe 15b. It is possible to realize almost uniform wear on the probe 15 (15a and 15b).

As a result, the durability of the probe device 10 can be substantially improved, and the probe 15 (15a
Also, accurate measurement can be performed without causing a measurement error due to the nonuniformity of the lengths of 15b) and without causing damage to the semiconductor chip 12.

As shown in FIG. 2, the tip portion 19 of the probe 15a corresponding to the power source bonding pad 13a is provided with a main needle portion 20 continuous with the inclined main body portion 18,
It can be a bifurcated portion composed of a main needle portion 20 and a sub needle portion 21. The main needle portion 20 is connected to the other probe 15b.
Is the same as the tip part in. Therefore, the probe 15a
Is the same as the configuration in which the sub needle portion 21 is added to the other probe 15b, and due to the cross-sectional area of the added sub needle portion 21,
The cross-sectional area of the tip portion 19 of the probe 15a is increased.

In the example shown in FIG. 2, the height position at the lower end of the auxiliary needle portion 21 is set slightly higher (Δh) than the height position at the lower end of the main needle portion 20. Therefore, due to the wear of the main needle portion 20, the lower end position of the main needle portion 20 is changed to the sub needle portion 2.
When the lower end position of No. 1 is reached, the auxiliary needle portion 21 functions and the cross-sectional area of the tip portion 19 is increased. The lower end positions of the main needle portion 20 and the sub needle portion 21 can be set to the same level.

The auxiliary needle portion 2 of the probe 15a shown in FIG.
1, the free end, which is the lower end, is bent toward the main needle portion 20 in the plane including the main needle portion 20 and the sub needle portion 21. Further, as in the example shown in FIG. 2, the height position at the lower end of the sub needle portion 21 is set slightly higher (Δh) than the height position at the lower end of the main needle portion 20.

In the example shown in FIG. 3, the absolute value of the angle α formed by the main needle portion 20 and the horizontal plane is the bending tip portion 2 of the auxiliary needle portion 21.
It is equal to the absolute value of the angle β formed by 1a with the horizontal plane. Therefore,
When the auxiliary needle portion 21 starts to function due to wear of the main needle portion 20, the cross-sectional area of the tip portion 19 increases and the tip portion 1
It can be expected that the wear of the needle 9 is reduced and that the tips of the main needle portion 20 and the auxiliary needle portion 21 mutually regulate the movements, and this regulation action causes the probe 15 to move.
It can be expected to prevent the displacement of the tip of the a.

In FIGS. 1 and 2, the chuck top 1 for mounting the semiconductor chip 12, which is the object to be measured, on the probe card 16 for supporting the probe 15.
Although the example in which 4 reciprocates toward or away from each other has been described, the probe card 16 can be reciprocated instead of the chuck top 14.

[0023]

In the probe device according to the present invention, the cross-sectional area at the tip portion of the probe, which is apt to cause wear corresponding to the power supply bonding pad, is made larger than those of other probes, so that the wear becomes higher than that of other probes. The surface pressure that the tip of the probe that easily produces from the semiconductor chip can be made lower than the surface pressure that other probes receive, and by reducing this surface pressure, wear of the probe that easily wears is suppressed, It is possible to prevent the probe length from becoming uneven due to uneven wear of the probe.

Therefore, according to the present invention, the measurement error due to the non-uniformity of the probe length is eliminated, and the semiconductor chip is prevented from being damaged by the probe. .

[Brief description of drawings]

FIG. 1 is a partially enlarged view showing a part of a first specific example of a probe according to the present invention in an enlarged manner.

FIG. 2 shows a second specific example of the probe according to the present invention.
FIG.

FIG. 3 shows a third specific example of the probe according to the present invention.
FIG.

FIG. 4 is a plan view of a probe device provided with a probe according to the present invention.

FIG. 5 is a cross-sectional view taken along line VV shown in FIG.

[Explanation of symbols]

 10 Probe Device 11 Semiconductor Wafer 12 Semiconductor Chip 13 (13a and 13b) Bonding Pad 15 (15a and 15b) Probe 16 Probe Card 19 Tip of Probe 20 Main Needle Part 21 Sub Needle Part

Claims (4)

[Claims] 1. A plurality of probes, each tip of which is pressed and connected to the corresponding bonding pad, for electrical characteristic testing of a semiconductor chip provided with a plurality of bonding pads including a power supply bonding pad. In the probe apparatus, the cross-sectional area of a tip portion of the probe corresponding to the power supply bonding pad is larger than that of a tip portion of another probe corresponding to another bonding pad. Probe device. 2. A probe card provided with a connection terminal connected to an electrical measuring device, the probe card supporting each probe connected to the corresponding connection terminal, wherein each probe is the probe. The probe device according to claim 1, wherein the probe device extends obliquely downward from the card toward the corresponding bonding pad of the semiconductor chip arranged below the central portion of the probe card. 3. The probe corresponding to the power supply bonding pad is provided with a forked portion including a main needle portion and a sub-needle portion branched from the main needle portion at a tip end portion thereof.
The described probe device. 4. The probe device according to claim 3, wherein a free end of the sub needle portion is bent toward a free end of the main needle portion.