JPH0516180B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for testing the characteristics of semiconductor wafer chips in a semiconductor manufacturing process.

[Prior Art] A wafer testing device is a device that tests semiconductor devices (hereinafter referred to as chips) completed in a semiconductor manufacturing process in the state of a wafer.

In general, this type of testing equipment consists of a wafer prober that brings probe needles into contact with electrode pads on each chip within the wafer, and a tester that electrically tests the characteristics of each chip via the wafer prober. Ru.

A probe card having a large number of probe needles arranged in an arrangement pattern corresponding to the pattern of the electrode pads is removably attached to the wafer prober. This probe card is designed to be replaced depending on the pattern of the electrode pads of the chip under test.

Generally, the wafer prober is fixedly arranged, and the mounting table on which the wafer under test is mounted is configured to be movable in the horizontal and vertical directions by an XY drive device and a lifting device. The probe card is attached to the wafer prober with the probe needles facing downward, and the mounting table approaches the wafer under test from below, so that each probe needle of the probe card touches the chip under test inside the wafer under test. It is adapted to make contact with each electrode pad.

The tester is placed on the opposite side of the wafer prober from the wafer under test (usually on the top side of the wafer prober).
to form an electrical connection with the probe card. As mentioned above, since the probe card is replaced depending on the pattern of the electrode pads, the tester must be removably attached to the wafer prober. Furthermore, it is preferable that the electrical connection established between the tester and the probe card be a contact-type electrical connection that can be easily removed, rather than a fixed electrical connection such as soldering or a connector.

Therefore, a perfboard equipped with an electrical connection mechanism called a pogo pin is attached to the tester, and the tester is removably attached to the wafer prober via this perfboard, and at the same time it is connected to the probe card. to establish an electrical connection between them.

[Problem to be solved by the invention] By the way, when the probe card is replaced,
The tester is removed from the wafer prober by being rotated away from the wafer prober by, for example, driving a rotating arm or the like. At this time, the performance board on the tester side is physically and electrically separated from the wafer prober.

Then, while a new probe card is attached to the wafer prober side, a new performance board corresponding to the new probe card is attached to the tester side as well.

After each new probe card and new performance board are installed, the tester is rotated in the opposite direction, that is, toward the wafer prober, and is installed on the wafer prober. At this time, the performance board of the tester is physically and electrically coupled to or in contact with the wafer prober.

However, in conventional wafer testing equipment,
It is difficult to accurately position the performance board on the tester side to the wafer prober, and if the tester is misaligned with the wafer prober, it will be forced to come together during installation, resulting in stress or distortion and deformation of various parts. There were problems such as the probe needle coming off the electrode pad.

The present invention was made in view of the above problems, and it is possible to accurately position the tester-side performance board to the wafer prober, establish a stable and reliable electrical connection between the tester and the probe card, and improve reliability. An object of the present invention is to provide a wafer testing device that can perform high quality tests.

[Means for Solving the Problems] In order to achieve the above object, a wafer testing device according to the present invention has a probe card equipped with a probe needle for contacting a semiconductor wafer attached to a wafer prober, and is movable. A perfboard equipped with an electrical connection mechanism is attached to the constructed tester, and the tester is removably attached to the wafer prober via the perfboard and at the same time electrically connected to the probe card. In the wafer testing apparatus, the wafer prober and the performance board are provided with first and second positioning means, respectively, and the performance board is aligned with the tester in a direction parallel to the board surface. The performance board is movable, and the performance board is positioned at a predetermined position of the wafer prober by aligning the second positioning means with the first positioning means.

[Operation] When connecting a tester to a wafer prober, the tester moves so as to overlap with the wafer prober. As a result, the second positioning means on the tester side is aligned with the first positioning means on the wafer prober side, for example, by a fitting method.

If the tester is misaligned with respect to the wafer prober, stress will occur between the first and second alignment means during such alignment. According to the present invention, since the performance board is movable relative to the tester in a direction parallel to the board surface, the performance board follows the wafer prober and moves in the same direction due to the effect of such stress. . As a result, the performance board is positioned at a predetermined position on the wafer prober side. Since the performance board absorbs the stress, no stress is applied to the probe card, so there is no risk of each probe needle being displaced.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows the configuration of essential parts of a wafer testing apparatus according to an embodiment of the present invention.

In this wafer testing apparatus, 5 is a semiconductor wafer as a test object, and 6 is a mounting table for this wafer 5. Further, each part 1a to 1f constitutes the tester 1. Other parts (2~
4, 7 to 9) are parts constituting a wafer prober.

The mounting table 6 is provided on the base 7 of the wafer prober, and is movable in the horizontal and vertical directions by an X-Y drive device and a lifting device (not shown). Above the mounting table 6, a probe card 4 having a large number of probe needles 4b arranged in a predetermined array pattern is attached to the wafer prober facing downward. The mounting table 6 is now positioned in the conventional manner so that the electrode pads of the chips under test in the wafer 5 placed on the mounting table 6 come into contact with the corresponding probe needles 4b from below. There is.

A plurality of main pillars 8 are erected on the base 7, and a head plate 9 is horizontally provided on these main pillars 8. An opening is formed in the center of the head plate 9, and a ring insert 2b is removably attached to the edge of this opening.

This ring insert 2b is secured to the head plate 9 at its outer annular portion, has a probe card 4 attached to the lower surface of the inner annular portion, and has alignment pins 3 erected on its upper surface.

In the tester 1, the test head 1K, which has a built-in electric circuit for wafer testing, is configured to be rotatable around a predetermined fulcrum by a rotation drive mechanism (not shown), and is mounted so as to cover the wafer prober from above. It is attached removably. A plurality of columns 1a are provided on the lower surface of the test head 1K, and a performance board 1c is removably attached to the lower ends of these columns 1a.

As shown in FIG. 1b, the lower end of each support 1a is cut out to form a small diameter section or groove 1f, and a groove 1e is opened at a predetermined position in the performance board 1c. The groove 1f of the support 1a loosely penetrates the groove 1a of the performance board 1c, and a screw is screwed into the lower end surface of the support 1a as a "flange".

With such a mounting structure, the performance board 1c is restricted from moving vertically with respect to the support column 1a and, by extension, with respect to the test head 1K. It is possible to move in parallel directions.

A large number of pogo pins 1d are inserted through the performance board 1c in a predetermined pattern at predetermined positions as an electrical connection mechanism for forming an electrical connection with a wafer prober. Each pogo pin 1d
terminal is connected to test head 1K via cable 1b.
is connected to the terminal.

In this embodiment, as shown in the figure, each pogo pin 1d
contacts each corresponding electrode 4a on the back surface (upper surface) of the probe card 4. On the other hand, in the probe card 4, each probe needle 4b on the front surface (lower surface) side and each electrode on the back surface (upper surface) side are electrically connected via through holes. Therefore, each pogo pin 1d of the performance board 1c contacts each corresponding electrode 55 on the back surface (upper surface) of the probe card 4, so that the tester 1 and each probe 4b of the probe card 4 are electrically connected. As a result, the tester 1 is electrically connected to each electrode pad of the chip under test within the wafer 5.

A positioning hole 1g corresponding to the positioning pin 3 on the wafer prober side is formed in the peripheral edge of the performance board 1c, and by fitting the positioning pin 3 into this positioning hole 1g, At the same time as tester 1 is attached to the wafer prober,
Each pogo pin 1d of the performance board 1c comes into contact with each electrode of the probe card 4.

In the wafer testing apparatus having such a configuration, when the probe card 4 is replaced, the tester 1 is rotated by the drive of the rotation drive mechanism.
The alignment hole 1g of the performance board 1c comes out of the alignment pin 3 of the wafer prober, and the entire tester 1 is separated from the wafer prober.

Then, on the wafer prober side, the ring insert 2b is removed from the head plate 9, and the ring insert 2b to which a new probe card 4 is attached is attached to the head plate 9. on the other hand,
On the tester 1 side, the performance board 1c is removed from the support 1a, and a new probe card 4 is installed.
A new performance board 1c provided with bogo pins 1d in a pattern corresponding to the above is attached to the support post 1a.

After the new probe card 4 and new performance board 1c are installed in this way, the tester 1 is driven by the rotary drive mechanism.
rotates in the opposite direction to that at the time of separation and overlaps the wafer prober, and the alignment pin 3 of the wafer prober fits into the alignment hole 1g of the performance board 1c.

At this time, if the test head 1k is misaligned with respect to the wafer prober, the respective positioning parts (3, 1g) will fit into each other, and horizontal stress will be applied to each of the wafer prober side and the tester 1 side. do. However, in this embodiment, since the performance board 1c is configured to be movable in the horizontal direction with respect to the test head 1K in the groove 1e, when connecting the tester 1 and the wafer prober, it is difficult to move in such a horizontal direction. When stress occurs, the performance board 1c is moved and positioned following the wafer prober side, so each pogo pin 3 of the performance board 1c must surely contact each electrode of the probe card 4. become. Furthermore, since the stress is absorbed by the performance board 1c, no stress or strain acts on the probe card 4. Therefore, there is no risk that each probe needle 4b will come off the electrode pad of the chip under test, and the pad size is, for example, 100 μm.
Even if the corner is large, the probe needle 4b can stably and reliably come into contact with the corner. As a result, in this wafer testing apparatus, highly accurate and reliable tests can be performed.

[Effects of the Invention] As explained above, according to the wafer testing apparatus of the present invention, the performance board can be moved in the direction parallel to the board surface with respect to the tester, and when the tester is attached to the wafer prober, Even if the tester is misaligned, the performance board moves to follow the wafer prober side and is positioned at the predetermined position on the wafer prober. There is no fear that the probe needle will shift, allowing highly accurate and reliable testing.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of essential parts of a wafer testing apparatus according to an embodiment of the present invention. 1... Tester, 1a... Support, 1c... Performance board, 1d... Pogo pin, 1e... Groove, 4... Probe card, 4b... Probe needle, 5... Wafer.

Claims (1)

[Claims] 1. A probe card equipped with a probe needle for contacting a semiconductor wafer is attached to a wafer prober, and a performance board equipped with an electrical connection mechanism is attached to a movable tester. , a wafer testing apparatus in which the tester is removably attached to the wafer prober via the performance board and at the same time electrically connected to the probe card; The performance board is configured to be movable relative to the tester in a direction parallel to the board surface, and the first and second positioning means are provided with a first and second positioning means. A wafer testing apparatus characterized in that the performance board is positioned at a predetermined position of the wafer prober by aligning the alignment means.