JPH02210276A - Prober - Google Patents

Abstract

PURPOSE:To deal with wafers of many kinds of size by a small-sized device by enabling a test head to move on an XY stage horizontally in at least one direction. CONSTITUTION:The test head 3 is fixed to a test head driving part 5. A column 54 is moved along a support rail 55 in the X direction so that the contact stylus of a probe card 32 fixed to the head 3 is at a measurement position P1. Here, a wafer which is already mounted on a chuck top 21 and aligned is aligned with the stylus and while the XY stage 2 is driven, for example, the right half part of the wafer W is measured. Then the column 54 is moved so that the contact stylus is at a measurement position P2, thereby measuring the left half of the wafer W similarly. The interval between the positions P1 and P2 is nearly a half as large as the width of the wafer W. In this case, a probing area can be narrowed down by the overlap of the wafer W. The interval between the positions P1 and P2 is selected properly to handle wafers W of many kinds of size.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a prober for testing the electrical characteristics of chips formed on a wafer.

[Prior art and problems to be solved by the invention] Conventionally,
As shown in FIG. 4, the prober transports the wafer W to be inspected from the loader section 50, places it on the chuck top 61 of the XY stage 60, and then aligns the XY axis of the XY stage 60 with the scrub line of the wafer in the alignment section. Then, the XY stage 6 is aligned at the brobbing section 70.
0, and then aligns and contacts each chip on the wafer W with the contact pins (probe card 80) on the test head 90 side.

Here, the test head 90 is attached to the prober body.

It is attached via an arm 91, and can be moved to a standby position away from the prober body when not measuring, but when measuring, it is placed on the top plate of the prober body and a probe card equipped with contact pins. , 80.

Therefore, during measurement, the test head 90 and probe card 80 are fixed to the prober body, and contact between the contact pins and the chip is achieved by moving mostly on the wafer side. Therefore, in order to move all the chips on the wafer for measurement while keeping the position P of the contact pins of the probe card 80 fixed, the probing area must be at least 4 wafer-sized as shown in FIG. This required double the area and required a larger XY stage to drive the wafer.

In particular, as large-sized wafers such as 8-inch wafers have been developed in recent years, probers that can handle such large-sized wafers have to be large, and the conventional 5.6-inch
Probers designed for inch wafers could not handle large wafers.

In particular, inspection of wafers must be carried out in a clean room, so it is important to make effective use of the clean room.
The increase in the volume occupied by the prober on the stand has become an extremely serious problem.

[Object of the Invention] The present invention has been made in view of such conventional problems, and provides a prober that can handle wafers of various sizes and further allows miniaturization of the entire device. The purpose is to

[Means for Solving the Problems] The prober of the present invention that solves these problems is
In a prober that electrically connects a test head to a workpiece chucked on a stage to inspect the workpiece, the test head is horizontally movable in at least one direction with respect to the stage.

[Operation] By horizontally moving the test head side in at least one direction, the amount of horizontal movement on the wafer side becomes relatively small. Therefore, when measuring wafers of the same size,
This makes it possible to probe with a smaller moving area than conventionally required, and it is possible to downsize the prober. Further, even if the prober is designed to measure wafers of a certain size or less, it is possible to measure larger wafers by horizontally moving the test head side.

[Embodiment] A preferred embodiment of the present invention will be described below with reference to the drawings.

The prober (Fig. 1) takes out wafers one by one from a cassette containing a plurality of wafers W, transports them, and returns the wafers to the cassette after measurement. an alignment section (not shown) for aligning the scrub line of the wafer with the XY axes of the XY stage 2;

It consists of a probing section 4 for measuring the electrical characteristics of the wafer after alignment while aligning it with the test head 3, and a test head housing section 5 for activating the test head 3.

The configurations of the loader section 1 and the alignment section are well known and will not be described here.

The probing section 4 does not include the insert ring section fixed to the top plate of the main body in the conventional prober. Instead, the insert ring part 31 is fixed to the test head 3. Therefore, the insert ring portion 31 moves together with the test head 3. This insert ring part 31 is attached with a probe card 32 equipped with a contact needle for contacting the chips of the wafer W, and also includes a rotation mechanism for the probe card 32 and a marking mechanism for marking defective chips as appropriate. Equipped with etc.

The test head 3 is fixed to the test head floating section 5 via an arm 51. The test head moving part 5 includes, for example, a horizontal shaft 53 that supports an arm 51 as shown in FIG.
It consists of a column 54 that supports the horizontal shaft 53 at both ends, a support rail 55 that supports the column 54 so as to be slidable in the X direction, and a drive means (not shown).

The support column 54 can be moved along the support rail 55 with a predetermined accuracy by a quick-acting means such as a step motor, so that the test head 3 and the probe card 31
can be moved in the X direction of the probing section 4.

The test head 3 can be rotated about the horizontal axis 53 manually or by other driving means, and can be moved to a standby position away from the probing section 4 when not making measurements. At this position, replace the probe card 32.
The insert ring 31 can be maintained and inspected.

Further, during measurement, the test head 3 is rotated in the opposite direction and moved to a predetermined position above the blobbing section 4. In this embodiment, the horizontal shaft 53 is equipped with a moving means such as a motor (not shown) and a rotation transmitting means 56 for transmitting the rotation of the motor to the horizontal shaft 53 as a quick-acting mechanism of the test head 3. The rotation transmitting means 56 is preferably of the kind described in Japanese Patent Application No. 134601/1983, which saves space and labor.

By rotating the horizontal shaft 53 using such a rotation transmission means, the test head 3 can be moved to a standby position during non-measurement or a position during measurement via the arm 51 fixed to the horizontal shaft 53. Furthermore, the position of the test head 3 during measurement can be changed by moving the column 54 along the support rail 55 in the X direction.

A blobbing method in the above configuration will be explained. First, before or after the test head 3 is rotated and set at the measurement position, the column 54 is moved in the X direction along the support rail 55, and the test head 3 is moved in the X direction along the support rail 55.
The contact needle of the probe card 31 fixed to the probe card 31 is placed at the first measurement position Hp (FIG. 3).

At this position, the aligned wafer W mounted on the chuck top is aligned, and while the XY stage 2 is being driven, a normal measurement is performed on, for example, the right half of the wafer W. Next, move the support column 54 to attach the probe card 3.
The first contact needle is placed at the second measurement position P2. P
It is preferable that the distance between P2 and P2 be approximately half the width of the wafer to be measured.

Perform needle alignment on the same wafer at measurement position P2,
Similar measurements are made on the left half. Note that alignment of the contact needle and the chip is usually performed using a microscope or a TV camera, but these devices also need to be movable.

In this case, as is clear from FIG. 3, it is possible to narrow the blobbing area by the amount of overlap between the wafers.

In addition, when measuring a relatively small wafer, the measurement is performed at one of the two measurement positions P, P2, or at an intermediate position, and when measuring a larger wafer, for example, two measurement positions are used. By measuring at different positions and appropriately selecting the interval between each measuring position, it is possible to handle wafers of various sizes.

In this embodiment, a configuration in which the test head 3 is horizontally moved only in the X direction has been described, but a configuration in which the test head 3 can be moved in the Y direction is also possible.

In this case 1, the support column 54 may be slidably attached to the support rail in the Y direction as in the case of a normal XY rail, and the support rail in the Y direction may be supported by the support rail 55 in the X direction.

This allows adjustment of both the width and depth of the blobbing area. It goes without saying that it is also possible to configure the test head 3 to move only in the Y direction.

Furthermore, in the above-mentioned prober, the test head 3 and the insert ring 31 (probe card 32) are integrated, but the insert ring can be attached to the top play 1 side in a state where it can move in conjunction with the test head or independently. You can.

[Effects of the Invention] As is clear from the above explanation, in the present invention, the test head and probe card, which were conventionally fixed, are moved horizontally with respect to the blowing area, so that the wafer can be moved relative to the wafer. The amount of movement can be reduced. Therefore, it is possible to reduce the size of the prober by narrowing the area of the probing area, and it is possible to handle wafers of various sizes.Furthermore, since it is equipped with a unique test head drive mechanism, the test head Easy to drive.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an embodiment of the prober of the present invention, Fig. 2 is a diagram showing an embodiment of the test head drive mechanism, and Fig. 3 is an illustration showing an embodiment of the probing method using the prober of the present invention. 4 are diagrams showing a conventional prober. 2...XY stage 3...Test head 32...Brobe force 5...Test head drive mechanism W...
・Wafer (object to be processed)

Claims (1)

[Claims] A prober that electrically connects a test head to a workpiece chucked on an XY stage to inspect the workpiece, characterized in that the test head is movable horizontally with respect to the stage.