Patent ID: 12259419

DETAILED DESCRIPTION

In a process of manufacturing a semiconductor device (hereinafter, referred to as a device), a plurality of devices are simultaneously formed on a substrate such as a semiconductor wafer (hereinafter, referred to as a wafer). The formed devices are tested with respect to their electrical properties and are classified into normal products and defective products. A test of a device is executed using, for example, a test device in a state before the substrate is divided into respective devices.

In a test device referred to as a prober, a mounting table configured to mount a substrate, on which a semiconductor device is formed, thereon or a transportation mechanism configured to transport a substrate is provided, and a probe card including a plurality of probes is mounted. In a test, the test device allows an electrode pad or a solder bump of the semiconductor device and the probe to be position-matched and come into contact with each other by relatively moving the mounting table and the probe card. In a contact state as described above, an electrical signal is supplied from a tester to the semiconductor device via the probe. Also, whether the semiconductor device is defective or not is determined on the basis of the electrical signal received by the tester from the semiconductor device via the probe.

When the above-described test is repeatedly performed, oxide on a surface of the electrode pad is attached to the needle tip of the probe or the needle tip of the probe is abraded, and, thus, polishing of the needle tip needs to be performed (refer to Japanese Patent Application Publication No. 2015-138888).

However, the test device of Japanese Patent Application Publication No. 2015-138888 does not include a mechanism configured to transport a needle tip contact portion on which a needle tip polishing surface is provided and which is supported by a support portion, and, thus, the test device has room for improvements in automatic exchange of the needle tip contact portion. Also, if a mechanism configured to transport the needle tip contact portion is additionally provided, automatic exchange is possible, but the test device becomes enlarged.

Further, it is considered that a shape and size of a needle tip polishing member is formed according to a shape and size transportable by the transportation mechanism for transporting a substrate under test, specifically, a shape and size equal to those of the substrate under test, so that the needle tip polishing member, that is, a polishing substrate is mounted on the mounting table instead of the substrate under test so as to be used for polishing the needle tips of the probe. In this configuration, although the needle tip polishing member is automatically exchangeable, it is necessary to remove the substrate under test from the mounting table in order to carry out the polishing, and, therefore, a throughput of the test is degraded.

To avoid the degrading of the throughput of the test, it is considered that a mounting table, on which the polishing substrate is mounted, is provided in addition to the mounting table on which the substrate under test is mounted. However, in this configuration, a space for retreating the substrate under test and the mounting table is necessary when carrying out the polishing by using the polishing substrate, and, thus, a footprint of the test device increases as much as the space required by additionally providing the mounting table on which the polishing substrate is mounted.

Accordingly, a technique according to the present disclosure polishes the probe using the polishing substrate transportable by the transportation mechanism for transporting the substrate under test, while suppressing device enlargement without degrading a throughput.

Hereinafter, a test device and a method of polishing a probe according to the embodiment will be described with reference to the drawings. Also, throughout the specification and drawings, elements having substantially like functions will be referred to as like reference numerals and a redundant description will be omitted.

First, components of the test device according to the embodiment will be described.FIGS.1and2are a perspective view and a longitudinal cross-sectional view schematically illustrating components of a test device1according to the embodiment, respectively.FIG.3is a plan view illustrating an element in which an accommodation chamber and a loader which will be described below are built.FIG.4is a plan view illustrating a polishing wafer which will be described below.FIG.5is a view illustrating a movement mechanism which will be described below.

The test device1is configured to test a wafer W under test as a substrate under test and, specifically, performs a test on electrical properties of a device (not shown) formed on the wafer W under test. On the wafer W under test, n (here, n is a natural number greater than or equal to two) number, that is, a plurality, of devices are formed. The test device1tests m (here, m is a natural number less than n) number of devices at the same time in one test. Also, the wafer W under test is formed to have, for example, a disc shape having a diameter of 300 mm.

As shown inFIGS.1and2, the test device1includes an accommodation chamber2in which the wafer W under test is accommodated while being tested, a loader3disposed to be adjacent to the accommodation chamber2, and a tester4disposed to cover a top of the accommodation chamber2.

As shown inFIG.2, the accommodation chamber2is a hollow housing and has a mounting table for test10on which the wafer W under test is mounted therein. The mounting table for test10suctions and retains the wafer W under test so as to maintain the position of the wafer W under test to be aligned with respect to the mounting table for test10. Further, the mounting table for test10includes a temperature adjustment mechanism configured to adjust the temperature of the wafer W under test which is mounted on the mounting table for test10. The temperature adjustment mechanism includes at least one of a heating mechanism (for example, a resistive heater) configured to heat the wafer W under test which is mounted on the mounting table for test10by heating the mounting table for test10and a cooling mechanism (for example, a flow channel through which a cooling refrigerant flows) configured to cool the wafer W under test which is mounted on the mounting table for test10by cooling the mounting table for test10.

In addition, a movement mechanism20is provided in the accommodation chamber2. The movement mechanism20may move the mounting table for test10and, specifically, may move the mounting table for test10in a horizontal direction and a vertical direction. Using the movement mechanism20, relative positions of a probe card P which will be described below and the wafer W under test are adjusted so as to allow an electrode on a surface of the wafer W under test to come into contact with a probe P1of the probe card P. Moreover, using the movement mechanism20, the mounting table for test10may be moved forward or backward with respect to the probe P1which will be described below. Accordingly, when the probe P1is polished by a polishing wafer K which will be described below, the mounting table for test10and the wafer W under test which is mounted thereon may be retreated to a retreat region T1(refer toFIG.3) spaced apart from the probe P1in a plan view.

For example, the movement mechanism20includes an X stage21and a Y stage22sequentially from below.

The X stage21is configured to be movable along a guide rail21aprovided on a bottom wall of the accommodation chamber2and elongating in an X direction (the width direction of the device) in the drawing. The Y stage22is configured to be movable along a guide rail22aprovided on the X stage21and elongating in a Y direction (the depth direction of the device) in the drawing.

The X stage21or the Y stage22includes, for example, a ball screw (not shown). A position of the X stage21in the X direction or a position of the Y stage22in the Y direction may be adjusted by adjusting a rotational amount of the ball screw using a motor (not shown) assembled with an encoder.

Also, the movement mechanism20includes a Z stage23on, for example, the Y stage22.

The Z stage23is provided on the Y stage22with an extensible shaft23ainterposed therebetween, the extensible shaft23aconfigured to be extensible in a Z direction (vertical direction) in the drawing, so that the Z stage23is liftable. For example, a motor assembled with an encoder is provided with respect to the extensible shaft23a, such that the length of the extensible shaft23amay be adjusted by adjusting a rotational amount of the motor, so as to adjust the position of the Z stage23in the Z direction.

On the Z stage23, the mounting table for test10is supported through a rotating mechanism24. The rotating mechanism24is a mechanism configured to rotate the mounting table for test10around a vertical axis and may adjust the direction of the wafer W under test which is mounted on the mounting table for test10by, for example, including a motor assembled with an encoder and adjusting the rotational amount of the motor.

The mounting table for test10may be moved in the X direction, Y direction, and Z direction using the X stage21, Y stage22, and Z stage23. Further, the direction of the wafer W under test which is mounted on the mounting table for test10may be adjusted as described above using the rotating mechanism24.

In the accommodation chamber2, the probe card P is disposed above the mounting table for test10. The probe card P includes the probe P1which comes into electrical contact with an electrode of a device formed on the wafer W under test when electrical properties of the device are tested. The probe P1is provided in a probe placement area Pa (refer toFIG.3) in a central portion of the probe card P in a plan view.

Furthermore, the probe card P is connected to the tester4via an interface30. When electrical properties are tested, each probe P1comes into contact with an electrode of each device formed on the wafer W under test, supplies power from the tester4to the device through the interface30, and transmits a signal from the device to the tester4through the interface30.

As shown inFIG.3, the loader3includes an accommodation unit3awhich accommodates a plurality of wafers W under test, a transportation mechanism3bconfigured to transport the wafer W under test, and a pre-alignment mechanism3cconfigured to adjust the direction of the wafer W under test.

Specifically, the accommodation unit3aaccommodates a front opening unified pod (FOUP) (not shown) which is a transportation container configured to accommodate the plurality of wafers W under test. The accommodation unit3ais provided on a front side (the negative side in the Y direction in the drawing) where a worker can easily work.

The transportation mechanism3btakes the wafer W under test out of the FOUP in the accommodation unit3aand loads it into the accommodation chamber2. Also, the transportation mechanism3btakes the wafer W under test, in which electrical properties of the device are completed, out of the accommodation chamber2and returns it to the FOUP in the accommodation unit3a.

The pre-alignment mechanism3cincludes a rotational mounting table3dconfigured to rotate the wafer W under test around the vertical axis, a light emitting and receiving unit (not shown) configured to detect a notch of the wafer W under test, or the like.

The tester4includes a test board (not shown) reproducing a part of circuit configuration of a motherboard on which a device is mounted. The test board is connected to a test computer (not shown) configured to determine whether the device is normal or defective on the basis of the signal from the device formed on the wafer W under test. In the tester4, circuit configurations of a plurality of types of motherboards may be reproduced by way of replacing the test board.

In the test device1, when electrical properties of the device formed on the wafer W under test are tested, the test computer transmits data to the test board connected to the device through each probe P1. Then, the test computer determines whether the transmitted data is accurately processed by the test board on the basis of an electrical signal from the test board.

Further, in the accommodation chamber2of the test device1, as shown inFIG.2, a mounting table for polishing40, on which the polishing wafer K used as a polishing substrate is mounted, is provided separately from the mounting table for test10. The mounting table for polishing40suctions and retains the polishing wafer K so as to maintain the position of the polishing wafer K to be aligned with respect to the mounting table for polishing40.

The polishing wafer K is a member configured to polish the probe P1(specifically, a needle tip thereof) and has a size and shape transportable by the transportation mechanism3b(refer toFIG.3). Specifically, for example, as shown inFIG.4, the polishing wafer K is a disc-shaped member like the wafer W under test, and has a diameter of about 150 mm to 300 mm. Also, in terms of the footprint of the test device1, it is preferable that the diameter of the polishing wafer K is small. However, when the diameter is smaller than 150 mm, it is impossible to retain the polishing wafer K using a transportation arm of the existing transportation mechanism3b. In addition, the polishing wafer K may be manufactured by, for example, attaching a polishing sheet (wrapping sheet) to a surface of a disc-shaped member.

The polishing wafer K may have a notch K1like the wafer W under test. Also, in the following description, a region on a side of the notch K1, when the polishing wafer K is divided into two parts in a plan view, is referred to as a first region R1and a region on the other side thereof is referred to as a second region R2.

By using the polishing wafer K as described above, the polishing wafer K may be automatically replaced by using the transportation mechanism3bwithout involving a human worker.

Furthermore, in accordance with the shape of the polishing wafer K, the mounting table for polishing40is formed to have a cylindrical shape and has a diameter slightly greater than the diameter of the polishing wafer K in a plan view.

The movement mechanism20provided in the accommodation chamber2ofFIG.2may move the mounting table for test10as well as the mounting table for polishing40. Specifically, the movement mechanism20may move the mounting table for polishing40and the mounting table for test10together in a horizontal direction and may move the mounting table for polishing40in the vertical direction independently from the mounting table for test10. By means of the movement mechanism20, the probe P1of the probe card P and the polishing wafer K mounted on the mounting table for polishing40may come into contact with each other. Also, since the mounting table for polishing40may be moved forward or backward with respect to the probe P1by the movement mechanism20, in a test on the wafer W under test which is mounted on the mounting table for test10, the mounting table for polishing40and the polishing wafer K mounted thereon may be moved to a retreat region T2(refer toFIG.3) spaced apart from the probe P1in a plan view.

That is, the movement mechanism20functions as a first forward or backward movement mechanism configured to move the mounting table for test10forward or backward with respect to the probe P1and also as a second forward or backward movement mechanism configured to move the mounting table for polishing40forward or backward with respect to the probe P1.

The mounting table for polishing40is movable in the X direction and Y direction by the X stage21and Y stage22like the mounting table for test10. That is, the mounting table for polishing40and the mounting table for test10share the movement mechanism in the X direction and the Y direction which are horizontal directions.

The movement mechanism20has a Z stage25above, for example, the Y stage22to allow the mounting table for polishing40to be movable in the Z direction.

The Z stage25is provided on the Y stage22with an extensible shaft25ainterposed therebetween, the extensible shaft25aconfigured to be extensible in the Z direction (vertical direction) in the drawing, so that the Z stage25is liftable. For example, a motor assembled with an encoder is provided with respect to the extensible shaft25a, so that the length of the extensible shaft25amay be adjusted by adjusting a rotational amount of the motor, so as to adjust the position of the Z stage25in the Z direction.

On the Z stage25, the mounting table for polishing40is supported through a rotating mechanism26. The rotating mechanism26is a device configured to rotate the mounting table for polishing40around a vertical axis and may adjust the direction of the polishing wafer K which is mounted on the mounting table for polishing40by, for example, including a motor assembled with an encoder and adjusting a rotational amount of the motor.

Also, as shown inFIG.3, in the test device1, an accommodation unit3ewhich accommodates a plurality of polishing wafers K is provided on the loader3. The accommodation unit3eis provided on an inner side of the loader3(the positive side in the Y direction in the drawing).

The polishing wafer K accommodated in the accommodation unit3eis taken out and carried into the accommodation chamber2by the transportation mechanism3band is mounted on the mounting table for polishing40.

When it is necessary to replace the polishing wafer K in the accommodation chamber2, the polishing wafer K is taken out and returned to the accommodation unit3eby the transportation mechanism3bwhile, simultaneously, a new polishing wafer K in the accommodation unit3eis carried into the accommodation chamber2by the transportation mechanism3b.

The test device1further includes a controller100. The controller100is configured, for example, by a computer, including a central processing unit (CPU), a memory, or the like, and includes a program housing portion (not shown). In the program housing portion, a program which controls a variety of processes in the test device1is housed. The program has been recorded in a non-transitory computer-readable storage medium and may be installed to the controller100from the storage medium. A part or the entirety of the program may be implemented as exclusive hardware (circuit substrate).

In the test device1configured as described above, as shown inFIG.3, the retreat region T1of the mounting table for test10by the movement mechanism20is located on a side opposite to the retreat region T2of the polishing wafer K by the movement mechanism20, with the probe placement area Pa interposed therebetween in a plan view. Also, in the test device1, in the polishing wafer K mounted on the mounting table for polishing40, a rear side portion thereof, which is on a side of the retreat region of the polishing wafer K, is not used for polishing of the probe P1, and only a front side portion thereof (the negative side in the Y direction in the drawing) on an opposite side is used for polishing of the probe P1. In other words, the movement mechanism20is configured to satisfy the following conditions.

(Conditions Satisfied by Movement Mechanism20)

In the polishing wafer K mounted on the mounting table for polishing40, a front side portion (the negative side in a Y direction ofFIG.5), as shown with a solid line inFIG.5, may be overlapped with the probe placement area Pa (that is, the probe P1) in a plan view. However, a rear side portion (the positive side in the Y direction inFIG.5) may not overlap the probe placement area Pa in a plan view as indicated by a double dot and dash line.

Specifically, to satisfy the above conditions, the movement mechanism20or the accommodation chamber2is structurally limited. For example, a length, a placement position, and the like of the guide rail22awith respect to the Y stage22of the movement mechanism20are set to satisfy the above conditions.

Here, a comparative example, which is different from the embodiment, will be described below. The comparative example has a configuration in which the movement mechanism20is configured to also overlap the rear side portion (the positive side in the Y direction ofFIG.5) of the polishing wafer K mounted on the mounting table for polishing40with the probe placement area Pa in a plan view as indicated by a double dot and dash line.

In the embodiment, in comparison to the comparative example, the distance in which the mounting table for polishing40moves toward the front side (the negative side in the Y direction inFIG.5) during the polishing is short, and, thus, the distance from the mounting table for test10located in the retreat region T1to the probe P1during the polishing in a plan view may be decreased. Accordingly, in the embodiment, it is possible to decrease the retreat region T1of the mounting table for test10, that is, a movement range of the mounting table for test10may be decreased. Accordingly, in the embodiment, enlargement of the test device1may be suppressed. In the comparative example, however, it can be clearly seen, from a state indicated by a double dot and dash line inFIG.5, in which the mounting table for test10and the like are not present in the accommodation chamber2, that the device is enlarged.

Also, even when only a front side portion (the negative side in the Y direction inFIG.5or the like) of the polishing wafer K mounted on the mounting table for polishing40is used for polishing of the probe P1as in the embodiment, an entire surface of the polishing wafer K may be provided for polishing without waste when performed as follows.

If the direction of the polishing wafer K mounted on the mounting table for polishing40is adjusted by rotating the mounting table for polishing40using the rotating mechanism26, the entire surface of the polishing wafer K may be provided for polishing without waste in the embodiment as well. Specifically, after the entire surface of the first region R1of the polishing wafer K, which was on the front side (the negative side in the Y direction inFIG.5or the like) is used for polishing, the polishing wafer K is rotated by 180° by rotating the mounting table for polishing40, so that the second region R2of the polishing wafer K, which was unused, may be provided on the front side (the negative side in the Y direction ofFIG.5or the like) so as to be used for the polishing.

Subsequently, an example of the test process by using the test device1will be described.

In the test, the wafer W under test is retreated from the FOUP in the accommodation unit3aof the loader3and carried into the accommodation chamber2by the transportation mechanism3b. Also, the wafer W under test, which was retained by the transportation mechanism3b, passes through a plurality of lifting pins (not shown) provided with respect to the mounting table for test10and is received by the mounting table for test10. That is, the wafer W under test is mounted on the mounting table for test10.

Subsequently, precise positions of the mounting table for test10and the probe P1are checked by a camera (not shown). Thereafter, the mounting table for test10is moved by the movement mechanism20, and the probe P1provided above the mounting table for test10comes into contact with the electrode of the device, which is under test, on the wafer W under test.

Then, a test signal is input to the probe P1. Accordingly, testing of electrical properties of the device under test is started. When testing of electrical properties is finished, the mounting table for test10is moved and testing of electrical properties with respect to a next device, which is under test, of the wafer W under test is performed.

Subsequently, until testing of electrical properties of all devices formed on the wafer W under test is completed, following processes after a process of mounting the wafer W under test are repeatedly performed. When the processes are completed, in a reverse order of carrying-in, the wafer W under test is retreated from the accommodation chamber2and returned to the FOUP in the accommodation unit3aof the loader3.

Consecutively, an example of polishing of the probe P1using the test device1will be described.

(Mounting)

First, the polishing wafer K is mounted on the mounting table for polishing40. Specifically, the polishing wafer K is taken out of the accommodation unit3eof the loader3and carried into the accommodation chamber2by the transportation mechanism3b. Also, the polishing wafer K, which was retained by the transportation mechanism3b, passes through a plurality of lifting pins (not shown) provided with respect to the mounting table for polishing40and is received by the mounting table for polishing40.

(Testing and Retreating of Mounting Table for Polishing40)

Thereafter, the above testing is performed. Here, the mounting table for polishing40is moved to the retreat region T2by the movement mechanism20and retreated from the probe P1.

(Polishing)

For example, during the above testing, when an error occurs in the probe P1, such as absence of electrical connection between the probe P1and the electrode on the wafer W under test, the testing of electrical properties of the device is stopped and the polishing of the probe P1is performed as follows. That is, the mounting table for test10is moved by the movement mechanism20and retreated from the probe P1while, simultaneously, the mounting table for polishing40is moved by the movement mechanism20and the probe P1is polished at a desired part of the front side portion (the negative side in the Y direction inFIG.5or the like) of the polishing wafer K mounted on the mounting table for polishing40. Polishing of the probe P1using the polishing wafer K is performed by overdriving the mounting table for polishing40, that is, by lifting the mounting table for polishing40by a certain distance from a position where the polishing wafer K and the probe P1come into contact with each other. Also, before the polishing of the probe P1, the accurate position of the probe P1is checked by the camera (not shown). The accurate position of the mounting table for polishing40may also be checked by the camera (not shown). Information on which part of the polishing wafer K has been used is stored in a memory (not shown) of the controller100.

In polishing, it is unnecessary to remove the wafer W under test from the mounting table for test10.

Also, when polishing is completed, testing of electrical properties of a device, which has been stopped, is restarted.

(Determination of Whether Entire Surface of Front Side Portion was Used)

Subsequently, the controller100determines whether the entire surface of the region which is on the front side (the negative side in the Y direction inFIG.5or the like) of the polishing wafer K mounted on the mounting table for polishing40was used for polishing.

(Determination of Whether Rear Side Portion was Used)

Further, when it is determined that the entire surface of the region which is on the front side of the polishing wafer K mounted on the mounting table for polishing40was used for polishing, the controller100determines whether a region which is on the rear side (the positive side in the Y direction inFIG.5or the like) of the same wafer K was used for polishing.

(Rotation)

When the region which is on the rear side was not used for polishing, the mounting table for polishing40is rotated by the rotating mechanism26, such that the direction of the polishing wafer K mounted on the mounting table for polishing40is adjusted. Specifically, for example, the polishing wafer k is rotated by 180°. Information on the rotating of the polishing wafer K is stored in the memory (of the controller100and is used for determination in the above-described process of determining whether the rear side portion was used.

(Replacement)

As a result of the process of determining whether the rear side portion was used, when it is determined that the region, which is on the rear side of the polishing wafer K mounted on the mounting table for polishing40, was also used for polishing, replacement of the polishing wafer K is performed. Specifically, the polishing wafer K to be replaced is retreated from the accommodation chamber2and returned to the accommodation unit3eof the loader3in a reverse order of carrying-in. Subsequently, a new polishing wafer K is retreated from the accommodation unit3eof the loader3and mounted on the mounting table for polishing40in the accommodation chamber2by the transportation mechanism3b. The replacement of the polishing wafer K is performed, for example, when replacement of the wafer W under test is performed.

In the above embodiment, the replacement of the polishing wafer K can be done by using the transportation mechanism3bconfigured to transport the wafer W under test, and, therefore, the probe P1is polished using the polishing wafer k which is automatically replaceable.

Also, in the embodiment, the mounting table for polishing40, on which the polishing wafer k is mounted, is provided separately from the mounting table for test10on which the wafer W under test is mounted. Accordingly, it is unnecessary to remove the wafer W under test from the mounting table for test10to polish the probe P1using the polishing wafer K, and, thus, there is no degrade in throughput of a test due to the automatic replacement of the polishing wafer K.

Also, in the embodiment, the movement mechanism20is configured such that the front side portion (the negative side in the Y direction ofFIG.5or the like) of the polishing wafer K mounted on the mounting table for polishing40may overlap the probe P1in a plan view while the rear side portion (the positive side in the Y direction ofFIG.5or the like) may not overlap the probe P1in a plan view. Accordingly, although the mounting table for polishing40is provided separately from the mounting table for test10, an increase in footprint of the test device1may be suppressed.

Accordingly, according to the embodiment, the probe P1may be polished by using the polishing wafer K configured to be transportable by the transportation mechanism3btransporting the wafer W under test while suppressing enlargement of the device without degrading the throughput of test.

In addition, even with the configuration of the embodiment, the entire surface of the polishing wafer K may be effectively provided for polishing without waste by way of adjusting the direction of the polishing wafer K mounted on the mounting table for polishing40by rotating the mounting table for polishing40by means of the rotating mechanism26.

Furthermore, instead of adjusting the direction of the polishing wafer K mounted on the mounting table for polishing40by rotating the mounting table for polishing40using the rotating mechanism26, the following adjustment may be performed. That is, the direction of the polishing wafer K mounted on the mounting table for polishing40may be adjusted by using the pre-alignment device3cas an adjustment mechanism. Specifically, after the entire surface of the first region R1of the polishing wafer K, which is on the front side (the negative side in the Y direction of the drawing) was used for polishing, the polishing wafer K is transported to the pre-alignment device3cfrom the mounting table for polishing40by using the transportation mechanism3b. Then, the polishing wafer K is rotated by 180° using the pre-alignment device3c, and, thereafter, the polishing wafer K is returned to the transportation mechanism3band the mounting table for polishing40, so that the polishing wafer K is mounted on the mounting table for polishing40while the second region R2, which was unused, is on the front side. Accordingly, the entire surface of the polishing wafer K may be provided for polishing without waste.

FIG.6is a cross-sectional view illustrating another example of the mounting table for polishing.

The mounting table for polishing40ofFIG.6includes a top plate200and a cooling unit210and a heating unit220as a temperature adjustment mechanism. The mounting table for polishing40is mounted on the movement mechanism20(refer toFIG.2or the like) with a heat insulation member300interposed therebetween.

The top plate200is a member on which the polishing wafer K is mounted and has, for example, a disc shape. One or a plurality of temperature sensors (not shown) are provided on the top plate200.

The cooling unit210is a member configured to cool the polishing wafer K mounted on the top plate200by cooling the top plate200. The cooling unit210is provided between the top plate200and the heating unit220.

Components of the cooling unit210are not particularly limited, and any components capable of cooling the top plate200may be included. As an example, a refrigerant flow channel (not shown) of the cooling unit210through which a refrigerant flows may be formed in the cooling unit210.

The heating unit220is a member configured to heat the polishing wafer K mounted on the top plate200by heating the top plate200. The heating unit220is disposed to face the top plate200with the cooling unit210interposed therebetween.

Components of the heating unit220are not particularly limited, and any components capable of heating the top plate200may be included. As an example, the heating unit220may include a resistive heater.

In the mounting table for polishing40ofFIG.6, the temperature of the polishing wafer K mounted on the mounting table for polishing40is adjusted by using the cooling unit210and the heating unit220. Specifically, in the mounting table for polishing40ofFIG.6, the temperature of the polishing wafer K mounted on the mounting table for polishing40is adjusted, by using the cooling unit210and the heating unit220, to a temperature, which is set in a test, of the wafer W under test which is mounted on the mounting table for test10.

A reason for adjusting a temperature as described above is as follows.

The temperature of the wafer W under test which is set in the test may be higher or lower than a room temperature (for example, 25° C.).

When the temperature of the wafer W under test, which is set in the test, is a high temperature, the probe card P may be, for example, heated through the probe P1by the high-temperature wafer W under test and a central portion thereof may be bent to protrude downward in the test. In this case, if the temperature of the mounting table for polishing40and the polishing wafer K mounted thereon is a room temperature, the probe card P, which is at a high temperature in the test or the like, is cooled through the probe P1by the polishing wafer K which is at the room temperature while the probe P1is polished by the polishing wafer K, such that the above bent state is released. As a result thereof, a contact pressure between the polishing wafer K and the probe P1during the polishing gets lower than a desired value, and, thereby, the probe P1is not appropriately polished, and in some cases, an electrical test cannot be appropriately performed using the probe P1after polishing.

Also, when the temperature of the wafer W under test, which is set in the test, is a low temperature, the probe card P may be, for example, cooled through the probe P1by the low-temperature wafer W under test, and the central portion thereof is bent to protrude upward in the test. In this case, if the mounting table for polishing40and the polishing wafer K mounted thereon are at a room temperature, the probe card P, which is low temperature in the test or the like, is heated through the probe P1by the polishing wafer K which is room temperature while the probe P1is polished by the polishing wafer K, so that a bent state is released. As a result thereof, a contact pressure between the polishing wafer K and the probe P1during the polishing gets higher than a desired value, that is, the probe P1is unnecessarily polished and, thereby, a life of the probe card P may be reduced.

In the mounting table for polishing40ofFIG.6, the temperature of the polishing wafer K mounted on the mounting table for polishing40is adjusted by the cooling unit210and the heating unit220as described above. Therefore, it is possible to minimize thermal variation of the probe card P, which is at a high temperature or low temperature during the test or the like, caused by the polishing wafer K. Accordingly, the probe P1is appropriately polished, the life of the probe card P is not reduced, and an electrical test may be appropriately performed using the probe P1after polishing.

In addition, any one of the cooling unit210and the heating unit220may be omitted. For example, when testing of electrical properties is only performed at a high temperature, the cooling unit210may be omitted.

It should be noted that the embodiment disclosed herein is exemplary in every aspect and is not limitative. The above embodiment may be omitted, substituted, and changed in a variety of forms without departing from the attached claims and a major point thereof