JPH0737946A - Probe device - Google Patents

Abstract

PURPOSE:To make it possible to align a probe device needle with a pad on a chip of a wafer automatically, by using an image input means for recognizing an alignment mark of the needle on a probe card, an image input means for recognizing a mark on a scribing line in the wafer, and an operation processing unit. CONSTITUTION:A chip reference mark is provided at a crossing point of scribing lines on a wafer. A prober includes a probe card 1 having needle alignment marks 2 and 3, a first image input means 6 for recognizing the needle alignment marks 2 and 3 on the probe card 1, a second image input means 4 for recognizing the chip reference mark on the wafer, and an operation processing unit 10 for making calculation on the basis of output data from the first and second image input means 4 and 6. Then, a needle 21 of the probe card 1 and the pad are aligned automatically on the basis of the needle alignment marks 2 and 3 of the probe card 1 and the chip reference mark on the wafer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe device, and more particularly to a probe device for automatically aligning a probe card needle with a bonding pad (hereinafter simply referred to as "pad").

[0002]

2. Description of the Related Art As a conventional probe device of this type, Japanese Patent Application Laid-Open No. 61-164165 discloses X, Y, .theta.
There is disclosed a probe device which recognizes a displacement amount of a needle and relative position information of a needle tip to perform automatic alignment.

The structure and operation of this probe device will be described below with reference to FIGS.

As shown in FIG. 4, the conventional probe device has an alignment mark 20 on the probe card 1, and the probe device is imaged with the CCD camera 4 for taking an image of the alignment mark 20. Alignment mark 20
It has a recognition device 7 for recognizing, a calculation processing device 10 for performing a predetermined calculation process on information from the recognition device 7, and reference position mark information 18 for providing information necessary for the calculation.

FIG. 5 shows an explanatory view of the arrangement of the alignment mark 20 and the probe. In FIG. 5, the distance between the tip of the probe needle 21 and the alignment mark 20 is fixed.

That is, by making the reference position mark information 18 and the alignment mark 20 attached to the probe card 1 coincide with each other, the tip of the probe needle 21 can be arranged at an appropriate position of the electrode pad.

Next, the operation will be described.

The alignment mark 20 on the probe card 1 attached to the probe device is imaged by the CCD camera 4, and the position of the alignment mark 20 is detected by the recognition device 7,
The detected value and the reference position mark information 18 are compared by the arithmetic processing unit 10 so that the portion where the probe card 1 is attached is in the X direction, the Y direction, so that the reference position mark information 18 matches the detected position.
Correct in the θ direction.

Further, as a conventional probe device, a further probe device is disclosed.
61-4989 and Japanese Patent Laid-Open No. 61-283138 have also proposed that the automatic alignment is performed by recognizing the displacement amounts of X, Y and θ of the alignment mark and the relative position information of the needle tip.

[0010]

However, in the conventional probe apparatus, since the chip position on the wafer is not recognized, the needle of the probe card and the pad cannot be aligned automatically.

Further, it is necessary to input information such as the relative coordinates of the needle tip, which causes problems such as complexity of inputting information necessary for setting and input error.

In particular, as the number of pins is increased due to higher integration and higher functionality of semiconductor chips, a large number of pads exist on the semiconductor chip, and the effort and input error for inputting the coordinates of the pads increase. In the conventional pad alignment, when the pad is designated on the monitor, there is a problem that it is difficult to determine which pad has the coordinate input.

As the conventional example, Japanese Patent Laid-Open No. 61-283138 discloses that
A probe device having a function of reading information from the information recording means and a function of automatically aligning a probe card and a wafer has been proposed, and data unique to the wafer such as the size of the IC chip of the wafer to be tested and the probe area is converted into a barcode. Although it is disclosed that the information is stored, since the position information of the chip on the wafer cannot be converted into a bar code, the pad designation on the monitor is still required, and a pad designation error or the like occurs.

Therefore, it is an object of the present invention to solve the above problems and provide a probe device capable of automatically aligning a needle of a probe card with a pad position on a chip formed on a wafer.

[0015]

In order to achieve the above-mentioned object, the present invention provides a probe card having a mark for needle alignment on the intersection of scribe lines of a wafer, and a needle alignment on the probe card. First image input means for recognizing the mark, second image input means for recognizing the mark on the scribe line of the wafer, and the first and second
And an arithmetic processing unit that performs an arithmetic operation based on the output information of the image input means, and aligns the probe card needle and the pad with reference to the needle alignment mark on the probe card and the scribe line on the wafer. Provided is a probe device for automatically performing.

Further, in the present invention, a probe device is provided in which a total of four needle positioning marks on the probe card are provided in the X and Y axis directions so that the center of the probe card is the origin of the coordinate system. I will provide a.

The present invention also provides a wafer provided with chip reference marks at the intersections of the scribe lines of the wafer for chip position recognition.

That is, according to the present invention, a mark indicating the X-axis, that is, a needle alignment mark x, which serves as a reference of the coordinates of the needle tip of the probe card, and a mark indicating the Y-axis, that is, the needle position, are provided at predetermined positions on the probe card. A first mark which is provided with an alignment mark y and which images the needle alignment mark
Image input means, an arithmetic processing unit that performs arithmetic processing based on the output signal from the first image input means, and a second image input means for picking up a chip reference mark on the wafer.

The arithmetic processing unit processes the output information of the image pickup image input means of the chip to detect the position of the chip.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows an outline of the whole constitution of the present invention.

As shown in FIG. 1, the needle positioning mark (x) 2 and the needle positioning mark (y) 3 provided on the probe card 1 are set so that the center of the probe card 1 is the origin. 4 (2 in each of the X and Y axis directions).

The needle alignment marks 2 and 3 may be provided on a holder (not shown) fixed to the probe card instead of being provided on the probe card 1.

The CCD camera 6 images the needle alignment marks 2 and 3, and the output signal of the CCD camera 6 is digitized by the recognition device 7 and taken into the video memory 8. The numerical data in the video memory 8 is Arithmetic processing is performed by the arithmetic processing unit 10 to calculate the deviation in the rotation direction.

At the same time, the arithmetic processing unit 10 calculates the central coordinate position of the probe card 1 from the measurement value of the XY movement distance measuring device 14.

After the wafer alignment (correction of the rotation direction in this case), the operator moves the prober stage 5 using the stage control stick 12 while looking at the wafer monitor 15, and the cross mark on the wafer monitor 15 is moved to the scribe line of the wafer. Chip reference mark 16 at the intersection of 17
To match.

The position of the prober stage 5 at this time is
Measurement is performed by the XY movement distance measuring device 14, the measured value is stored in the memory 9, and the arithmetic processing unit 10 calculates the chip center position.

Next, the stage controller 11 reads the displacement in the direction of rotation of the prober stage 5 from the memory 9,
The stage drive unit 13 is instructed to correct the rotational displacement, and the stage drive unit 13 moves the prober stage 5 to correct the rotational displacement.

Then, the stage controller 11 commands the stage drive unit 13 to move the prober stage 5 so that the center coordinate position of the probe card 1 coincides with the chip center.

By the above sequence, the alignment of the probe card needle and the pad is completed.

In the present embodiment, the needle alignment marks (x) 2 and (y) 3 of the probe card are detected by the CCD camera 6 and, for example, two needle alignment marks (x) 2 in the X direction are detected. Calculate the deviation of the probe card 1 in the rotation direction by detecting each and calculating the coordinates,
Also, a needle alignment mark (x) in the X and Y directions
Since the intersection point connecting (2) and (3) indicates the center position of the tip of the probe card 1, the center position of the tip with respect to the needle of the probe card 1 can be detected from the four needle alignment marks.

The prober stage 5 is moved so that the chip center position detected from the chip reference mark 16 and the position of the chip center on the probe card 1 detected from the needle alignment marks 2 and 3 on the probe card 1 coincide with each other. Then, the needle of the probe card and the pad are aligned.

In the above alignment sequence,
The position data when the operator aligns while looking at the wafer monitor 15 is stored in the memory 9 as the information of the product, so from the next time, the chip reference mark 16 on the wafer will be the CCD camera 4 and the recognition device 7. The arithmetic processing unit 10 automatically detects by image recognition based on the information stored in the video memory 8 via, and the needles of the probe card and the pads are all aligned automatically.

That is, in the embodiment of the present invention, the manual operation by the operator described above is performed by changing the position of the chip reference mark 16 on the wafer to the probe device when the probe card 1 is replaced due to the switching of the device under test. This is an auxiliary operation for storing, and the probe device automatically detects the chip reference mark 16 from the next wafer via the CCD camera 4.

The chip reference mark on the wafer will be described with reference to FIG. Figure 2 shows the chip reference mark on the wafer
It is explanatory drawing which showed 16 typically.

As shown in FIG. 2, the chip reference mark 16
Are formed at the intersections of the scribe lines 17, which are the boundaries that separate the semiconductor chips formed on the wafer.

The chip reference mark 16 is formed of Al (aluminum) and is formed in the Al wiring process of the semiconductor chip. Preferably, the mark has a line width of about 10 μm.
The size is about 100 μm.

Next, with reference to FIG. 3, the processing operation of the alignment in this embodiment will be described.

First, the needle alignment marks 2 and 3 on the probe card 1 are detected, and the rotation direction of the wafer is corrected based on the detection.

When the probe card 1 is replaced, the following processing is performed.

The probe device detects the four needle alignment marks on the new probe card 1, recognizes the misalignment in the rotational direction and the coordinate system of the needle alignment marks, and detects the center position of the chip with respect to the needle of the probe card. To detect.

The operator aligns the chip reference mark 16 at the intersection of the scribe lines 17 on the wafer with the cross mark on the monitor.

The position of the prober stage 5 aligned by the processing is stored (the center coordinate position on the probe card 1 and the coordinates of the chip reference mark 16 are also stored).

Probe card 1 detected in processing
Of the prober stage 5 to correct the deviation of the rotation direction of the
Is corrected in the direction of rotation.

The chip center position of the probe card needle detected in the process is aligned with the chip center position on the wafer.

When the probe card 1 is not replaced, the tip center of the probe card needle and the tip center of the wafer are determined based on the previous data calculated and stored by the processing from the above according to the branch of FIG. By aligning, the needle of the probe card and the pad are aligned.

In the present embodiment, the coordinate input of the pad,
Further, the pad is not designated on the monitor, and the cross mark on the monitor is merely aligned with the chip reference mark provided on the scribe line on the wafer, and the alignment work is extremely simplified.

[0048]

As described above, according to the present invention, the probe card is provided with the needle alignment mark, the wafer is provided with the chip reference position mark, and the CCD camera is provided on each of the prober stage side and the probe device side. The present invention achieves the automation of the alignment of the probe card needle and the pad, which has conventionally been performed manually every time the probe card is replaced, and has the effect of improving work efficiency and productivity particularly.

Particularly, in the present invention, it is still necessary in the conventional probe apparatus in which the alignment is automated.
There is no need to input the coordinates of the needle position, input of the pad coordinates, designation on the monitor, etc., and the alignment of the needle and the pad is a supplementary and simple work just by matching the cross mark on the monitor and the tip reference mark. Therefore, the input error is eliminated and the working efficiency is particularly improved.

Further, according to the present invention, after performing an auxiliary work for aligning the needle and the pad of the probe card in the probe card exchange, the alignment of the needle and the pad is performed through the image input means. It is all done automatically based on the information entered.

Further, in the present invention, the wafer on which the chip reference mark is formed during the Al wiring step realizes the automation of the alignment of the probe card needle and the pad.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is an explanatory view schematically showing a chip reference mark provided on a scribe line of a wafer.

FIG. 3 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 4 is a schematic configuration diagram showing an example of a configuration of a conventional probe device.

FIG. 5 is an explanatory diagram of a needle alignment mark on a probe card according to a conventional technique.

[Explanation of symbols]

 1 probe card 2 needle alignment mark (x) 3 needle alignment mark (y) 4,6 CCD camera 5 prober stage 7 recognition device 8 video memory 9 memory 10 arithmetic processing device 11 stage controller 12 stage controller stick 13 stage Drive unit 14 XY moving distance measuring device 15 Wafer monitor 16 Chip reference mark 17 Scribe line 18 Reference position mark information 19 θ rotation device 20 Alignment mark 21 Probe needle

Claims (3)

[Claims] 1. A probe card provided with a chip reference mark at an intersection of scribe lines on a wafer and having a needle alignment mark, and a first image input means for recognizing the needle alignment mark on the probe card. A second image input unit for recognizing a chip reference mark on the wafer; and an arithmetic processing unit for performing an arithmetic operation based on the output information of the first and second image input units, and needle position adjustment on the probe card. A probe device that automatically aligns the probe card needle and pad with reference to the wafer mark and the wafer chip reference mark. 2. A total of four needle alignment marks, two in each of the X and Y axis directions, are provided on the probe card so that the center of the probe card is the origin of the coordinate system. The probe device according to claim 1. 3. A wafer, wherein a mark having a predetermined line width is formed as a chip reference mark for alignment in a probe device at the center of the intersection of scribe lines.