JPH11251379A - Wafer probing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain stable contact between a probe card and a semiconductor wafer corresponding to the inclination of the probe card. SOLUTION: A wafer probing device is provided with a wafer stage 1, on which a semiconductor wafer W is put and with a probe card 2 which makes contact with the semiconductor wafer W on the wafer stage 1. An X-Y direction drive means that the wafer stage 1 is moved in an X-direction and a Y-direction crossing at a right angle with the X-direction, and a Z-direction drive means that the wafer stage 1 is moved in a Z-direction, crossing a right angle with a horizontal plane. An inclination adjusting part 8 is provided between an X- direction drive part 60 of the X-Y direction drive means 6 and a Z-direction drive part 7. Through the inclination adjusting part 8, an inclination with respect to the horizontal plane of the wafer stage 1 can be adjusted.

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 wafer probing apparatus for performing an electrical test by bringing a probe needle of a probe card into contact with a semiconductor wafer on a wafer stage.

[0002]

2. Description of the Related Art FIGS. 7 and 8 show an example of a conventional wafer probing apparatus. In FIG. 7, the wafer probing apparatus includes a wafer stage 1 for mounting a semiconductor wafer W, and a probe card 2 having a plurality of probe needles 20 for contacting the semiconductor wafer W on the wafer stage 1. ing. Probe card 2
Are supported by the head plate 3. An insert ring 4 having a plurality of pogo pins 40 is attached to the head plate 3 above the probe card 2.

[0005] Above the head plate 3, there is provided a test head 5 that is pressed against the insert ring 4 from above. This test head 5 is a performance board (attachment board) that is pressed into contact with the upper ends of the plurality of pogo pins 40 of the insert ring 4.
52.

Next, as shown in FIGS. 7 and 8, the wafer probing apparatus moves the wafer stage 1 in an X direction on a horizontal plane and in a Y direction orthogonal to the X direction (FIG. 8).
XY direction driving means 6 for moving the XY direction. Further, the wafer probing apparatus includes a Z-direction drive unit 7 for moving the wafer stage 1 in a Z direction (see FIG. 8) orthogonal to a horizontal plane.
The XY direction driving means 6 includes an X direction driving unit 60 and a Y direction driving unit 65 each including a slider 61, 66 and a pair of screw rods 63, 68.

[0005] Then, this wafer probing apparatus
The positioning of the semiconductor wafer W with respect to the probe card 2 in the XY direction (index operation) is performed by the XY direction driving means 6, and the semiconductor wafer W is brought into contact with the probe card 2 at a predetermined pressure by the Z direction driving unit 7. , An electrical test is performed. In this case, the probe card 2 is configured such that the wafer stage 1 can be further raised within the range of 60 to 100 μm even after the first contact of the semiconductor wafer W with the tip of the probe needle 20 (the allowable range of the so-called overdrive amount). 60 to 100 μm). This is for ensuring that all the probe needles 20 of the probe card 2 can contact the semiconductor wafer W.

[0006]

The above-mentioned conventional wafer probing apparatus has the following problems. That is, the head plate 3 supporting the probe card 2 must be essentially parallel to the wafer stage 1, but the head plate 3 is bent by the pogo pin pressure (300 kg or more) of the pogo pin 40 of the insert ring 4 and the head plate 3 itself becomes large. It is difficult to keep the parallelism accurately due to the accuracy limit and the like accompanying the development. Also, the attachment / detachment (up / down) of the test head 5 and the probe card 2
In some cases, the impact of the attachment / detachment (replacement) causes the inclination of the head plate 3 to change.

[0007] The probe card 2 is also inclined with the inclination of the head plate 3. If the difference between the needle heights of the probe needles 20 (relative to the wafer stage 1) is 40 μm or more, the overdrive is performed. The difference cannot be absorbed within the allowable range of the amount, and the probe needle 2
0 contact failure occurs.

In particular, in recent years, the so-called needle holder area of the probe card 2 has been expanded so that simultaneous measurement of 32 and 64 probes can be performed, so that the influence of the inclination of the head plate 2 is increasing.

The present invention has been made in view of the above points, and provides a wafer probing apparatus capable of maintaining stable contact between a probe card and a semiconductor wafer in accordance with the inclination of the probe card. The purpose is to do.

[0010]

A first means includes a wafer stage for mounting a semiconductor wafer, a probe card having a plurality of probe needles for contacting the semiconductor wafer on the wafer stage, The wafer stage is moved on a horizontal plane in an X direction and a Y direction orthogonal thereto.
XY-direction driving means for moving the wafer stage in a direction, Z-direction driving means for moving the wafer stage in a Z direction orthogonal to the horizontal plane, and adjusting the inclination of the wafer stage with respect to the horizontal plane. And a tilt adjustment means.

According to the first means, by adjusting the inclination of the wafer stage with respect to the horizontal plane by the inclination adjusting means, it is possible to carry out the test while keeping the probe card and the wafer stage almost parallel at all times. Become.

A second means for detecting a tilt of the probe card with respect to the horizontal plane in the first means, and a tilt corresponding to the tilt of the probe card detected by the tilt detector; Control means for controlling the tilt adjusting means so as to adjust the tilt of the wafer stage.

Third means is the first means, wherein the inclination detecting means for detecting the inclination of the probe card with respect to the wafer stage, and the inclination of the probe card with respect to the wafer stage detected by the inclination detecting means. Control means for controlling the tilt adjusting means so as to adjust the tilt of the wafer stage until the tilt is substantially eliminated based on the above.

According to the second or third means, the inclination of the wafer stage can be automatically adjusted so that the probe card and the wafer stage are kept substantially parallel.

[0015] A fourth means is the second or third means, wherein the inclination detecting means measures the height of at least three measurement points on the probe card, and determines a difference in height between these measurement points. Is used to detect the inclination of the probe card.

The fifth means is any one of the second to fourth means, wherein the control means corresponds to the tilt of the wafer stage adjusted by the tilt adjusting means,
This is to correct the displacement of the amount of movement in the X and Y directions by the XY direction driving means.

According to the fifth means, in any one of the second to fourth means, the displacement of the movement amount in the X direction and the Y direction accompanying the adjustment of the tilt of the wafer stage is corrected, so that the probe card Accurate contact between each probe needle and the corresponding measurement site on the semiconductor wafer can be maintained.

[0018]

Next, an embodiment of the present invention will be described with reference to the drawings. 1 to 6 are views showing an embodiment of a wafer probing apparatus according to the present invention. In the embodiment of the present invention shown in FIGS. 1 to 6, the same components as those in the conventional example shown in FIGS. 7 and 8 are denoted by the same reference numerals.

First, an embodiment of the present invention will be described with reference to FIGS. First, in FIG. 1A, a wafer probing apparatus has a wafer stage 1 for mounting a semiconductor wafer W and a probe card having a plurality of probe needles 20 for making contact with the semiconductor wafer W on the wafer stage 1. 2 is provided. The probe card 2 is supported by the head plate 3. An insert ring 4 having a plurality of pogo pins 40 is provided on the head plate 3 above the probe card 2.
Is installed.

A test head 5 is provided above the head plate 3 and pressed against the insert ring 4 from above. The test head 5 has a head main body 50 and a performance board (attachment board) 52 provided at the bottom of the head main body 50, and the latter 52 presses and contacts the upper ends of the plurality of pogo pins 40 of the insert ring 4. It is supposed to be.

Next, as shown in FIGS. 1 and 2, the wafer probing apparatus moves the wafer stage 1 in an X direction on a horizontal plane and in a Y direction orthogonal to the X direction (FIG. 2).
XY direction driving means 6 for moving the XY direction. The wafer probing apparatus further includes a Z-direction drive unit (Z-direction drive means) 7 for moving the wafer stage 1 in a Z direction (see FIG. 2) orthogonal to a horizontal plane.

The XY direction driving means 6 includes an X direction driving section 60 and a Y direction driving section 65, for example, as shown in FIGS. Each of the X-direction drive unit 60 and the Y-direction drive unit 65 includes a slider 61, 66 and a pair of screw rods 63, 68 screwed to the sliders 61, 66, respectively. Note that this XY
The direction driving unit 6 may be one in which an X-direction driving unit and a Y-direction driving unit are integrally formed, such as a linear motor type wafer stage driving mechanism.

And, this wafer probing apparatus
The positioning of the semiconductor wafer W with respect to the probe card 2 in the XY direction (index operation) is performed by the XY direction driving means 6, and the semiconductor wafer W is brought into contact with the probe card 2 at a predetermined pressure by the Z direction driving unit 7. , An electrical test is performed. In this case, the probe card 2 is configured such that the wafer stage 1 can be further raised within the range of 60 to 100 μm even after the first contact of the semiconductor wafer W with the tip of the probe needle 20 (the allowable range of the so-called overdrive amount). 60 to 100 μm). This is for ensuring that all the probe needles 20 of the probe card 2 can contact the semiconductor wafer W.

Here, this wafer probing apparatus
A tilt adjusting section (tilt adjusting means) 8 is provided between the X direction driving section 60 and the Z direction driving section 7. The tilt adjusting section 8 is for adjusting the tilt of the wafer stage 1 with respect to the horizontal plane. Specifically, for example, as shown in FIGS. 1 and 2, the tilt adjusting unit 8 includes a square base plate 80 connected to the wafer stage 1 via the Z-direction driving unit 7, and four corners of the base plate 80. And a total of four threaded rods 84 penetrating the portion. Each screw rod 84
The X-direction drive unit 60 extends upward from the slider 61. At the four corners of the base plate 80, ball joints 82 that are rotatable three-dimensionally are provided, and threaded rods 84 are screwed to these ball joints 82.

Then, the tilt adjusting section 8 is arranged as shown in FIG.
As shown in FIG. 2, by rotating each screw rod 84, the height of the four corners of the base plate 80 with respect to the slider 61 of the X-direction drive unit 60 is changed.
The inclination of the wafer stage 1 with respect to the horizontal plane can be adjusted.

Next, the wafer probing apparatus has an inclination detecting means for detecting an inclination of the probe card 2 with respect to the wafer stage 1. This inclination detecting means includes a needle height measuring section 9 shown in FIGS. 1, 2 and 4, and an inclination calculating section 10 shown in FIG. Here, as shown in FIG. 3, the probe needles (measurement points) A, B, C, and D at the four corners among the probe needles 20 of the probe card 2.
Are registered in advance. And the needle height measuring unit 9
Are measured points A, B,
The needle height at C and D (the height of the tip of the probe needle 20 with respect to the wafer stage 1) is measured.

The inclination calculating section 10 is provided with a needle height measuring section 9.
The inclination of the probe card 2 with respect to the wafer stage 1 is calculated based on the difference between the needle heights of the measurement points A, B, C, and D measured by the measurement.

Next, this wafer probing apparatus is provided with a control section (control means) 11 shown in FIG. The control section 11 controls the operations of the XY direction driving means 6, the Z direction driving section 7, and the tilt adjusting section 8. Further, the control unit 11 calculates a tilt correction value of the wafer stage 1 such that the tilt is substantially eliminated, based on the tilt of the probe card 2 with respect to the wafer stage 1 detected by the tilt detection means 9 and 10, and calculates the tilt correction value. The inclination adjusting unit 8 is configured to be controlled based on the inclination correction value.

As shown in FIG. 4, the control section 11 includes a shift calculating section. In the shift calculating section, the control section 11 corresponds to the tilt (tilt correction value) of the wafer stage 1 adjusted by the tilt adjusting section 8. , X-Y direction driving means 6 is configured to calculate the deviation of the movement amount in the X direction and the Y direction. That is, as shown in FIG. 1B, when the tilt of the wafer stage 1 is adjusted by the tilt adjusting unit 8, the position of the semiconductor wafer W on the wafer stage 1 is shifted in the X-Y direction (in FIG. 1B, A shift d in the X direction occurs. Therefore, the control unit 11 calculates a shift correction value for correcting the shift, and based on the shift correction value,
The control is performed to correct the displacement of the movement amounts in the X direction and the Y direction by the XY direction driving means 6.

Here, although partially overlapping with the above description, a main control operation in the wafer probing apparatus having such a configuration will be described with reference to FIG. First, in step S1, the needle height of the previously registered measurement points A, B, C, D (see FIG. 3) of the probe card 2 is measured by the needle height measuring unit 9 of the inclination detecting means. Next, in step S2, in the inclination calculating section 10 of the inclination detecting means, the measurement points A,
The controller 11 calculates the inclination of the probe card 2 with respect to the wafer stage 1 based on the difference between the needle heights of B, C, and D, and the controller 11 calculates the inclination of the probe card 2 calculated by the inclination calculator 10. Then, a tilt correction value of the wafer stage 1 is calculated so that the tilt is almost eliminated.

Next, in step S3, the control unit 11 controls the tilt adjusting unit 8 based on the calculated tilt correction value to adjust the tilt so that the tilt of the probe card 2 with respect to the wafer stage 1 becomes almost zero ( (Tilt correction).

In parallel with this, in step S4, the deviation calculating section of the control section 11 adjusts the inclination (tilt correction value) of the wafer stage 1 by the inclination adjusting means 8 in the XY directions. X direction and Y by driving means 6
A displacement of the moving amount in the direction and a displacement correction value for correcting the displacement are calculated. Then, in step S5, the calculated deviation correction value is set for the XY direction driving means 6.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, the controller 11 controls the tilt adjusting means 8 based on the tilt of the probe card 2 with respect to the wafer stage 1 detected by the tilt detecting means, and
Is automatically adjusted so that the inclination with respect to the wafer stage is almost eliminated, so that the test can be performed while the probe card 2 and the wafer stage 1 are always kept substantially parallel.

Therefore, a highly reliable test can be performed while maintaining stable contact between the probe card 2 and the semiconductor wafer W corresponding to the inclination of the probe card 2.
In addition, since the operation of correcting the inclination between the probe card 2 (head plate 3) and the wafer stage 1, which varies for each individual wafer probing device, is automated, the operation efficiency can be greatly improved.

Further, the controller 11 controls the X-axis according to the tilt of the wafer stage 1 adjusted by the tilt adjusting means 8.
Since the displacement of the movement amount in the X direction and the Y direction by the Y direction driving means 6 is corrected, accurate contact between each probe needle 20 of the probe card 2 and the corresponding measurement site (test pad) on the semiconductor wafer W is performed. Can be kept.

Next, another embodiment of the present invention will be described with reference to FIG. This embodiment is different from the above embodiment in that a part of the control operation shown in FIG. 5 is changed as shown in FIG. 6, and other configurations are the same as the above embodiment shown in FIGS. is there.

That is, in the present embodiment, control operations such as steps S10 to S14 shown in FIG. 6 are performed instead of steps S1 and S2 shown in FIG. Specifically, in FIG. 6, first, the test head 5 is raised (Step S10), and in this state, the needle height (first time) is measured by the needle height measuring unit 9 (Step S11). Next, the test head 5 is lowered and pressed against the insert ring 4 (step S1).
2) In this state, the needle height (second time) is measured again by the needle height measuring unit 9 (step S13).

In step S14, the inclination calculator 10 of the inclination detector detects the wafer stage of the probe card 2 based on the difference between the first and second needle heights measured by the needle height measuring unit 9. In addition to calculating the inclination with respect to 1, the inclination correction value is calculated based on the inclination.

According to the present embodiment, the inclination is calculated based on the difference between the needle heights before and after the test head 5 is pressed, so that the inclination of the probe card 2 (head plate 3) due to the pressing of the test head 5 is calculated. More accurate tilt detection can be performed in consideration of the change.

In the inclination detecting means, the probe height (measurement point) at the four corners of the probe card 2 is measured by the needle height measuring section 9
The case where the needle heights of A, B, C, and D are measured and the inclination of the probe card 2 is calculated based on the needle heights has been described. However, the present invention is not limited thereto. , Some measurement point (eg mark)
May be set, these positions are registered in advance, and the inclination of the probe card 2 may be calculated based on the heights of these measurement points.

A case where the inclination detecting means detects the inclination of the probe card 2 with respect to the wafer stage 1 and controls the adjustment of the inclination of the wafer stage 1 so that the inclination of the probe card 2 with respect to the wafer stage 1 is almost eliminated. Although described, the present invention is not limited to this. For example, the inclination of the probe card 2 with respect to the horizontal plane is detected by the inclination detection means, and the inclination of the wafer stage 1 with respect to the horizontal plane is adjusted in accordance with the inclination of the probe card 2 so that the wafer of the probe card 2 with respect to the horizontal plane is used as a reference. It may be configured to perform a tilt adjustment control such that the tilt with respect to the stage 1 is almost eliminated.

[0042]

According to the present invention, by adjusting the inclination of the wafer stage with respect to the horizontal plane by the inclination adjusting means, it is possible to carry out a test while always keeping the probe card and the wafer stage substantially parallel. . Therefore, a highly reliable test can be performed while maintaining stable contact between the probe card and the semiconductor wafer in accordance with the inclination of the probe card.

[Brief description of the drawings]

FIG. 1A is a side view partially showing a wafer probing apparatus according to an embodiment of the present invention in a longitudinal section, and FIG.
A part of the wafer probing device shown in FIG.
FIG. 4 is a diagram showing a state of adjusting the tilt of the wafer stage.

FIG. 2 is a partially omitted perspective view of the wafer probing apparatus shown in FIG.

FIG. 3 is a bottom view of a probe card in the wafer probing apparatus shown in FIG.

FIG. 4 is a block diagram showing a main part of a control system in the wafer probing apparatus shown in FIG. 1;

FIG. 5 is a flowchart showing main control operations in the wafer probing apparatus shown in FIG.

FIG. 6 is a flowchart showing a control operation (a part different from the control operation shown in FIG. 5) in another embodiment of the wafer probing apparatus according to the present invention.

FIG. 7 is a side view partially showing a conventional wafer probing apparatus in a longitudinal section.

8 is a partially omitted perspective view of the wafer probing apparatus shown in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wafer stage 2 Probe card 20 Probe needle 3 Head plate 4 Insert ring 40 Pogo pin 5 Test head 6 XY direction drive unit 60 X direction drive unit 65 Y direction drive unit 7 Z direction drive unit (Z direction drive unit) 8 Tilt Adjusting unit (tilt adjusting unit) 9 Needle height measuring unit (tilt detecting unit) 10 Tilt calculating unit (tilt detecting unit) 11 Control unit (control unit) A, B, C, D Measurement point W Semiconductor wafer

Claims (5)

[Claims] 1. A wafer stage on which a semiconductor wafer is mounted, a probe card having a plurality of probe needles for contacting the semiconductor wafer on the wafer stage, and a wafer stage in an X direction on a horizontal plane. XY direction driving means for moving the wafer stage in the Y direction orthogonal thereto, Z direction driving means for moving the wafer stage in the Z direction orthogonal to the horizontal plane, and the horizontal plane of the wafer stage And a tilt adjusting means for adjusting a tilt with respect to the wafer. 2. An inclination detecting means for detecting an inclination of the probe card with respect to the horizontal plane, and adjusting the inclination of the wafer stage in accordance with the inclination of the probe card detected by the inclination detecting means. 2. The wafer probing apparatus according to claim 1, further comprising control means for controlling said tilt adjusting means. 3. An inclination detecting means for detecting an inclination of the probe card with respect to the wafer stage; and, based on the inclination of the probe card with respect to the wafer stage detected by the inclination detecting means, until the inclination is substantially eliminated. 2. The wafer probing apparatus according to claim 1, further comprising control means for controlling said tilt adjusting means so as to adjust the tilt of said wafer stage. 4. The method according to claim 1, wherein the inclination detecting means measures the height of at least three measurement points on the probe card, and detects the inclination of the probe card based on a difference in height between the measurement points. 4. The method according to claim 2, wherein
A wafer probing apparatus as described in the above. 5. The apparatus according to claim 1, wherein the control means corrects a displacement of the movement amount in the X and Y directions by the XY direction driving means in accordance with the tilt of the wafer stage adjusted by the tilt adjusting means. The wafer probing apparatus according to any one of claims 2 to 4, wherein: