JPH02119157A - Testing device - Google Patents

Abstract

PURPOSE:To maintain stable contact during the test and achieve a higher density test with a larger number of probes by bringing a test subject and the probes in contact with each other without overshoot by means of a stretching means provided on the sample base side. CONSTITUTION:A semiconductor wafer 4 is placed on the upper surface of a first sample base 7 and fixed by means of vacuum chuck hole 7a. Then, the sample base 1 is raised by an elevation driving part 13 to cause solder bumps 4a to approach the probes 3a. Next, a buffer member 10 is stretched by a predetermined amount by a control means 11 to raise the sample base 7 without overshooting to press the extremities of the probes 3a onto the bumps 4a to carry out a predetermined test. Thus, the plastic deformation of the probes can be prevented to maintain a stable contact, and by providing the buffer base on the sample base side to eliminate the space limitation between the probes to increase the number of the probes to achieve higher density test.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inspection technique, and particularly to a technique that is effective when applied to wafer testing performed in the manufacture of semiconductor devices.

[Conventional technology]

For example, regarding wafer tests carried out in the wafer processing process in the manufacture of semiconductor devices, see "Electronic Materials J 19" published by Kogyo Kenkyukai Co., Ltd., November 15, 1986.
It is described in the November 1987 special edition, pages 183 to 190.

The outline of this method is to bring a probe into contact with external connection electrodes formed on individual semiconductor elements on a semiconductor wafer, establish electrical continuity between each semiconductor device and an external tester via the probe, and It is described that a predetermined operating signal is applied to determine whether or not operating characteristics are satisfied.

By the way, as individual semiconductor devices become more highly integrated and densely packed, the number of external connection electrodes tends to increase. It is becoming more and more common.

For this reason, it is necessary to increase the number of probes and increase their density, but when the probe contacts an externally connected electrode as in the past, the elasticity of the bent probe causes the individual probes to separate. In the method of press-contacting externally connected electrodes, the probes come into contact with each other, making inspection impossible.

Therefore, instead of the conventional method, it is conceivable to have a large number of probes implanted in a highly rigid probe card in a crest shape, and to bring the probes into contact with external connection electrodes.

In other words, it is conceivable to place a semiconductor wafer on a sample stand that can be raised and lowered, and to fix the probe of the probe card to the semiconductor wafer so that it faces the semiconductor wafer, and to bring it into contact by raising the sample stand using a stepping motor or the like. .

[Problem to be solved by the invention]

However, in the method described above in which the probe is brought into contact with the semiconductor wafer by the upward movement of the sample stage, so-called overshoot, which occurs when the probe returns too far from a predetermined stopping position, does not occur due to the inertia of the sample stage or drive system. Unavoidably, when the sample stage returns to the predetermined stopping position, a gap will be created between the probe, which has been plastically deformed at the closest position due to overshoot, and the solder bump, resulting in poor contact during inspection, etc. The present inventor has discovered that this is a contributing factor.

Therefore, in order to prevent such poor contact, a structure is adopted in which an elastic means such as a spring is incorporated into the probe itself, and the probe is pressed into contact with the external connection electrode by the elastic force or elastic force of the elastic means. However, with such a structure, the space between the probes is restricted due to the built-in structure of the expansion and contraction means, which prevents an increase in the number of probes and a high density.

Furthermore, if the expansion/contraction means is provided on the probe side, the expansion/contraction means must be provided for each of various probe cards with different arrangement intervals and numbers of probes, that is, for each of the various probe side structures.

An object of the present invention is to provide an inspection technique that can stably maintain contact between a variety of objects to be inspected and a probe using a single structure, and that can increase the number of probes and increase the density of the probes. It is about providing.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means to solve the problem]

A brief overview of typical inventions disclosed in this application is as follows.

That is, it consists of a sample stage that supports a plate-shaped object to be inspected, and a plurality of probes that are protruded and disposed opposite to the object to be inspected placed on the sample platform. An inspection device that performs a predetermined inspection by bringing the object to be inspected and the probe into contact by relatively displacing the sample stage, wherein the object to be inspected and the probe come into pressure contact when they come into contact with each other. A telescopic means for this purpose is provided on the sample stage side.

[Effect]

According to the above-mentioned means, the object to be inspected and the probe are brought into pressure contact when they come into contact via the expansion and contraction means provided on the sample stand side, so that overflow due to inertia of the sample stand or the drive system of the sample stand can be avoided. Excessive plastic deformation of the probe caused by the chute is avoided, and stable contact between the object to be inspected and the probe can be maintained during inspection.

In this case, since the expansion and contraction means is provided on the sample stage side, the space between the probes is not limited by the expansion and contraction means, so it is possible to increase the number of probes and increase the density of the probes. In addition, it is possible to avoid the necessity of providing an expansion/contraction means for each of various structures on the probe side in which the arrangement intervals and number of probes are different.

[Embodiment] FIG. 1 is an explanatory diagram partially showing the main parts of an inspection apparatus which is an embodiment of the present invention, and FIGS. 2(a), 2(a) and 2(c).

(d), (e), and (f) are explanatory views showing modified examples of the expansion and contraction means used in the present invention, respectively.

The inspection apparatus of this embodiment is configured as a wafer blower in the manufacture of semiconductor devices.

A base 2 is provided above the sample stand 1, which is set almost horizontally, in a posture facing parallel to the sample stand 1, and a probe card 3 is mounted on the surface of the base 2 facing the sample stand 1. fixed horizontally.

A semiconductor wafer 4 (object to be inspected) is mounted on the probe card 3.
A plurality of probes 3a are arranged at a predetermined pitch to correspond to each of a plurality of solder bumps 4a provided on each semiconductor element formed in the semiconductor device, and protrude vertically downward.
Each probe 3a is connected to a tester 6 via a cable 5 connected to a probe card 3.

The sample stand 1 is vertically divided into multiple stages, and the divided first sample stand 7 and second sample stand 8 form the sample stand 1.

A vacuum suction hole 7a for a chuck connected to the vacuum piping 9 is provided on the upper surface of the first sample stage 7, and the semiconductor wafer 4 is suctioned and positioned by the vacuum suction hole 7a, and the semiconductor wafer 4 is positioned on the first sample stage 7. It is removably placed on the top surface of the

Further, a large diameter guide portion 7b is provided at approximately the center of the lower side of the first sample stage 7, protruding vertically downward, and a guide portion 7b of a large diameter is provided on the outer peripheral portion of the lower side of the first sample stage 7 at equal intervals in the outer circumferential direction. A plurality of guide pins 7C are provided to protrude vertically downward.

On the other hand, the second sample stage 8 has a large diameter guide hole 8a.

A small diameter guide hole 8b is formed, and the guide holes 8a, 8
Since the guide portion 7b and the guide pin 7C are loosely inserted in b, the first sample stage 7 is supported on the second sample stage 8 so as to be vertically displaceable while being prevented from rotating in the horizontal plane. has been done.

Between the first sample stage 7 and the second sample stage 8, one or more buffer members 10 (expandable means) such as an air bag are interposed along the outer circumferential direction between the two.

In this way, the extensible means of this embodiment is formed by the buffer body 10 as shown in FIG. 1, but the extensible means of the present invention is, for example, as shown in FIG. 2(a).

(bl, an elastic body made of rubber or sponge with a cross-sectional shape as shown in (C) 10a1, a pogo contact pin 10b as shown in (d) in the same figure, a spring 10C1 as shown in (e) and (f) in the same figure) A piezoelectric actuator 10d such as a piezo element as shown in the figure can be used.

In the piezoelectric actuator 10d illustrated last, for example, when a voltage of about 10 to 100 OV is applied, the piezoelectric actuator 10d expands by about 10 to 100 μm in the vertical direction in FIG. 2 in proportion to the voltage.

When this piezoelectric actuator 10d is used as an expansion/contraction means of an inspection device, for example, the vertical expansion/contraction direction generated in the piezoelectric actuator 10d in accordance with the voltage applied to the piezoelectric actuator 10d under the control of a predetermined control means. The structure is such that the first sample stage 7 is slightly moved in the vertical direction due to strain, so that the first sample 70 does not overshine.

The buffer body 10 of this embodiment is configured such that its expansion and contraction in the vertical direction in FIG. 1 is controlled by a control means 11.

The second sample stage 8 is supported via a vertical lift shaft 12 by a lift drive 113 composed of, for example, a stepping motor. It is fixed on top of 15.

By combining the movement of the X-Y stage 15 in the horizontal plane and the vertical movement of the lift drive section 13, positioning of the second sample stage 8 in the horizontal and vertical directions is performed.

In addition, the vertical movement of the second sample stage 8 by the vertical drive unit 13;
The vertical movement of the first sample stage 7 due to the expansion and contraction of the buffer body 10 is carried out in coordination with the control means 11, etc.
After approaching the probe 3a via the sample stage 8, the buffer 10
is extended under the control of the control means 11, and the first sample stage 7 is further moved slightly and brought into pressure contact with the probe 3a.
The structure is such that the probe 3a is brought into contact with the solder bump 4a of the semiconductor element and is securely pressed against the solder bump 4a of the semiconductor element so that the first sample stage 7 does not overshine.

The operation of this embodiment will be explained below.

First, the semiconductor wafer 4 is placed on the upper surface of the first sample stage 7 in a predetermined posture with the solder bumps 4a facing upward, and is fixed by suction from the vacuum suction holes 7a.

Next, by appropriately moving the x-y stage 15, a target semiconductor element among a plurality of semiconductor elements (not shown) formed on the semiconductor wafer 4 is positioned directly under the probe 3a, and the sample stage 1 By appropriately rotating the solder bumps 4a, the parallelism between the array direction of the plurality of solder bumps 4a and the array direction of the probes 3a can be adjusted.

Thereafter, the lift drive unit 13 is activated to raise the sample stage 1 to a predetermined height, thereby touching the tip of the probe 3a and the solder bumps 4 of the semiconductor wafer 4 placed on the first sample stage 7.
a to a predetermined distance in a non-contact state.

Next, the buffer body 10 is extended by a predetermined amount under the control of the control means 11, and the first sample stage 7 is held in a predetermined position while maintaining a parallel attitude above the tip of each probe 3a, without causing an opening or the like. the tip of each probe 3a to a plurality of solder bumps 4 on the target semiconductor element.
The individual probes 3a are pressed securely by a predetermined amount to each of the probes 3a.
and solder bump 4a are electrically connected securely.

In this state, operating power, operation test signals, etc. are exchanged between the tester 6 and a semiconductor element (not shown) formed on the semiconductor wafer 4 via the cable 5 and the plurality of probes 3a, etc. Determine whether or not the operating characteristics of the

The series of operations described above is performed for each of the plurality of semiconductor elements formed on the semiconductor wafer 4, and it is determined whether the operating characteristics of all the semiconductor elements are good or not.

Then, the semiconductor elements determined to be unsuitable are eliminated, for example, in the subsequent sealing process after the guising process.

As described above, in this embodiment, the first step is to bring the solder bumps 4a formed on the semiconductor wafer 4 close to the tip of the probe 3a to a predetermined distance by the lifting operation of the sample stage 1 driven by the lifting drive section 13. and a second stage in which the tip of the probe 3a is brought into pressure contact with the solder bump 4a by the upward displacement of the first sample stage 7 without overshoot due to the expansion of the buffer 10, and then through the buffer 10. probe 3a
Since the tip of the probe 3a is pressed against the solder bump 4a, the plurality of solder bumps 4a and the probe 3a are brought into contact with each other, so that excessive plastic deformation occurs when the probe 3a and the like come into contact with the solder bumps 4a. This prevents the occurrence of gaps.

As a result, the solder bumps 4 of a plurality of semiconductor elements (not shown) formed on the semiconductor wafer 41 during testing, etc.
It becomes possible to reliably maintain the electrical connection between a and the probe 3a, stable test results can be obtained, and a highly rigid probe 3a can be used.

Furthermore, in this embodiment, the buffer 10 is provided on the sample stage 1 side, not on the probe 3a side, so that the space between each probe 3a is limited by the buffer IO, etc. Since there are no probes 3a, it is possible to increase the number of probes 3a and increase the density of the probes 3a.This makes it possible to inspect the semiconductor wafer 4 having a large number of solder bumps 4a, and also to reduce the distance between the probes 3a and the probes 3a. It is possible to avoid the necessity of providing the buffer body 10 for each of various probe cards 3 having different numbers.

As above, the invention made by the present inventor has been specifically explained based on Examples, but it should be noted that the present invention is not limited to the Examples and can be modified in various ways without departing from the gist thereof. Not even.

For example, the buffer lO in this example has a control hand al.
It is said that it has a structure that expands and contracts under the control of l.
For example, when the elastic body 10a of the Klli body 101, the pogo contact pin 10b, the spring lOc, etc. are used as the stretching means of the present invention, their expansion and contraction are not controlled, and the object to be inspected is affected only by their own buffering force or elasticity. It may also have a structure that maintains stable contact with the probe.

Further, in the rotation prevention mechanism of the first sample stage 7 in this embodiment, the guide portion 7b and the guide pin 7C are connected to the guide holes 3a and 3b.
Although the structure is such that they are loosely inserted into each, a rotation prevention mechanism such as a guide rail or engagement may also be used.

Furthermore, in this embodiment, when the sample stage 1 and the probe 3a approach each other, the second sample stage 8 rises, causing the sample stage 1 side to approach the probe 3a side. To,
It is also possible to have a structure in which the probe 3a side is close to the sample stage l side.

The above explanation has mainly been about the case where the invention made by the present inventor is applied to the wafer test technology in the manufacturing of semiconductor devices, which is the field of application in which the invention was made by the present inventor. It can be widely applied to testing techniques for conducting tests.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

That is, it consists of a sample stage that supports a plate-shaped object to be inspected, and a plurality of probes that are protruded and arranged opposite to the object to be inspected placed on the sample stand, and that An inspection device that performs a predetermined inspection by bringing the probe into contact with the probe,
By having a structure in which an extensible means for pressure contact between the object to be inspected and the probe is formed on the sample stand side, the object to be inspected can be moved through the extensible means provided on the sample stand side. Since the probe and the probe are in pressure contact when they come into contact, excessive plastic deformation of the probe due to overshoot due to inertia of the sample stage or the drive system of the sample stage is avoided, and the object to be inspected and the probe are Stable contact with the needle can be maintained.

In this case, by providing the expansion and contraction means on the sample stage side, the space between the probes is not limited by the expansion and contraction means, so it is possible to increase the number of probes and increase the density of the probes. In addition, it is possible to avoid the need to provide expansion and contraction means for each structure on the probe side in which the arrangement interval or number of probes is different.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a partial cross section of the main part of an inspection device which is an embodiment of the present invention; FIG. 2 (a), (a), (c), (d), (e)
(f) and (g) are explanatory diagrams showing modified examples of the expansion/contraction means used in the present invention. DESCRIPTION OF SYMBOLS 1... Sample stage, 2... Base, 3... Probe card, 3a... Probe, 4... Semiconductor wafer (object to be inspected), 4a... Solder bump, 5... Cable, 6.
...Tester, 7...First sample stage, 7a...Vacuum suction hole, 7b...Guide portion, 7C...Guide pin, 8.
...Second sample stage, 3a, 3b...Guide hole, 9...
Vacuum piping, 10...Buffer (expansion/contraction means), 10a...
・Elastic body (expandable means), 10b... Pogo contact pin (expandable means), 10C... Spring (expandable means), 10
d...Piezoelectric actuator (expansion/contraction means), 11...
Control means, 12... Lifting shaft, 13... Lifting drive unit,
14... Housing, 15... X-Y stage. Figure 2

Claims (1)

[Claims] 1. Consisting of a sample stage supporting a plate-shaped object to be inspected, and a plurality of probes protruding and arranged opposite to the object to be inspected placed on the sample stand. , an inspection device that performs a predetermined inspection by bringing the object to be inspected and the probe into contact by displacing the sample stage relative to the probe,
An inspection apparatus characterized in that an expanding and contracting means for press-contacting the object to be inspected and the probe when they come into contact is provided on the sample stage side. 2. The inspection apparatus according to claim 1, wherein the expansion and contraction means is controlled by a predetermined control means to be expandable and retractable in the direction of approach and separation between the probe and the object to be inspected. 3. The inspection apparatus according to claim 1 or 2, wherein the sample stage is separated into a plurality of stages, and the buffer means is interposed between the separated sample stages.