Inspection apparatus, inspection system, and aligning method

The present disclosure is provided with a probe card and a transfer stage for transferring an inspection target toward the probe card. The transfer stage is provided with a chuck top on which the inspection target is mounted, an aligner configured to be contacted to or separated from the chuck top, and an aligning mechanism for aligning the chuck top with the aligner. The aligning mechanism has radially-expandable positioning pins at a plurality of positions on the upper surface of the aligner, and pin insertion members at positions on the lower surface of the chuck top corresponding to the positioning pins, the pin insertion members having pin insertion holes of which diameters are larger than those of the positioning pins that are not radially expanded. The chuck top is aligned with the aligner by inserting the positioning pins into the pin insertion holes and radially expanding the positioning pins.

TECHNICAL FIELD

The present disclosure relates to an inspection apparatus and an inspection system for inspecting electrical characteristics of a target object, and an aligning method.

BACKGROUND

In a process of manufacturing a semiconductor device, electrical characteristics of a plurality of semiconductor devices (hereinafter, simply referred to as “devices”) formed on a wafer are inspected after all processes are performed on a semiconductor wafer (hereinafter, simply referred to as “wafer.”) An inspection apparatus (prober) for performing such inspection includes a probe card having contact probes that are multiple contact terminals. By bringing the wafer into contact with the probe card, the contact probes are brought into contact with electrode pads or solder bumps of the devices. Then, electricity is allowed to flow from the contact probes to electric circuits of the devices connected to the electrodes to thereby inspect the electrical characteristics such as conduction states of the electric circuits and the like using a tester (see, e.g., Patent Document 1).

Recently, there was suggested a wafer inspection system capable of improving an inspection efficiency. This wafer inspection system includes a plurality of inspection apparatuses, each having a probe card and a tester. In this wafer inspection system, while a wafer is being transferred to one inspection apparatus by a transfer stage including an aligner and a chuck top, devices formed on the wafer can be inspected by another inspection apparatus. In this wafer inspection system, when the wafer is brought into contact with a probe card of each inspection apparatus, the space between the chuck top for attracting and holding the wafer and the probe card is depressurized. Accordingly, the electrodes of the devices formed on the wafer and the contact probes of the probe card can be brought into contact with each other in a state where the chuck top is attracted (see, e.g., Patent Document 2).

In the inspection system disclosed in Patent Document 2, the transfer stage is formed by connecting the chuck top and the aligner (chuck base). The wafer W is mounted, attracted, and held on the chuck top. Then, the chuck top is aligned by the aligner. Next, the chuck top is lifted and attracted by the aligner. Thereafter, the aligner is separated from the chuck top and moved to another inspection apparatus (tester). Then, the aligner is connected to a chuck top on which an inspected wafer is mounted and transfers the inspected wafer.

In this case, when the aligner and the chuck top are connected to each other, it is required to accurately align the chuck top with respect to the aligner in a plane direction, a vertical direction, and a rotation direction.

Therefore, in Patent Document 3, the inspection apparatus in which the aligner and the chuck top can be brought into contact with each other or separated from each other includes an aligning mechanism having a plurality of positioning pins formed on an upper surface of the aligner and a plurality of positioning blocks having V-shaped grooves and formed on a bottom surface of the chuck top to correspond to the positioning pins. The aligner and the chuck top are aligned by engaging the positioning pins with the positioning blocks.

PRIOR ART

Patent Document 1: Japanese Patent Application Publication No. 2009-204492

Patent Document 2: Japanese Patent Application Publication No. 2014-75420

Patent Document 3: Japanese Patent Application Publication No. 2017-69427

The present disclosure provides a technique capable of aligning a chuck top for holding an inspection target to be in contact with contact probes of a probe card and an aligner for aligning the chuck top with high accuracy in the case where the chuck top and the aligner can be brought into contact with each other or separated from each other.

SUMMARY

In accordance with an aspect of the present disclosure, there is provided with an inspection apparatus comprising: a probe card that has multiple contact probes to be in contact with an inspection target and that is connected to a tester to inspect electrical characteristics of the inspection target; and a transfer stage configured to transfer the inspection target toward the probe card, wherein the transfer stage includes: a chuck top configured to mount thereon the inspection target; an aligner that is configured to be brought into contact with the chuck top or separated from the chuck top and configured to move the chuck top; and an aligning mechanism configured to align the chuck top and the aligner, wherein the aligning mechanism has a plurality of radially-expandable positioning pins disposed on one between a bottom surface of the chuck top and an upper surface of the aligner, and a plurality of pin insertion members that are disposed on the other one between the bottom surface of the chuck top and the upper surface of the aligner and that correspond to the positioning pins, each of the pin insertion members having a pin insertion hole of which diameter is greater than a diameter of the positioning pin that is not radially expanded, and the chuck top and the aligner are aligned with each other by moving the aligner toward the chuck top, inserting the positioning pins into the pin insertion holes, and radially expanding the positioning pins.

Effect

The present disclosure provides a technique capable of aligning a chuck top for holding an inspection target to be in contact with contact probes of a probe card and an aligner for aligning the chuck top with high accuracy in the case where the chuck top and the aligner can be brought into contact with each other or separated from each other.

DETAILED DESCRIPTION

First, an overall configuration of an example of an inspection system will be described.

FIG. 1is a horizontal cross-sectional view schematically showing the overall configuration of the example of the inspection system.FIG. 2is a vertical cross-sectional view taken along a line II-II′ inFIG. 1.

As shown inFIGS. 1 and 2, the inspection system10includes a housing11. The housing11has an inspection area12for inspecting electrical characteristics of semiconductor devices of a wafer W, a loading/unloading area for loading/unloading the wafer W or the like with respect to the inspection area12, and a transfer area14disposed between the inspection area12and the loading/unloading area13.

In the inspection area12, tester rows, in each of which a plurality of (six in this example) testers15serving as wafer inspection interfaces are arranged along the Y direction inFIG. 1, are arranged in three stages along the Z direction (vertical direction). Further, one tester side camera16(inclination checking mechanism) is arranged for each tester row. Each tester side camera16moves horizontally along a tester row corresponding thereto, and is positioned in front of each tester15of the tester row to determine a position of a wafer W or the like transferred by a transfer stage18to be described later or a degree of inclination of a chuck top29to be described later. A probe card19is attached to each tester15as will be described later. An inspection unit30is configured as a mechanism for bringing a wafer W on the chuck top29to be described later into contact with contact probes25of the probe card19.

The loading/unloading area13is partitioned into multiple ports including a wafer loading/unloading port17a, an aligner port17b, a loader port17c, and a control unit accommodation port17d. The wafer loading/unloading port17aaccommodates a FOUP that is a container where a plurality of wafers is stored. The aligner port17baccommodates an aligner for aligning the wafer. The loader port17caccommodates a loader into and from which the probe card19is loaded and unloaded. The control unit accommodation port17daccommodates a control unit70for controlling operations of each of the components of the inspection system10.

In the transfer area14, a transfer stage18that is movable along the Y direction and also movable toward the inspection area12or the loading/unloading area13is disposed. One transfer stage18is provided to correspond to each tester row. The transfer stage18transfers the wafer W from the wafer loading/unloading port17ain the loading/unloading area13to each tester15, and also transfers the wafer W having the semiconductor devices of which electrical characteristics have been inspected from each tester15to the wafer loading/unloading port17a.

In this wafer inspection system10, the electrical characteristics of the devices of the wafer W transferred to each inspection unit30(tester15) are inspected. As will be described later, while the transfer stage18is transferring the wafer W toward one inspection unit30, other inspection units30can inspect the electrical characteristics of the devices of other wafers W.

The control unit70includes a main controller having a CPU (computer) and configured to control the respective components of the inspection system10, an input device (keyboard, mouse, or the like), an output device (printer or the like), a display device (display, or the like), and a storage device (storage medium). The respective components of the inspection system10are the tester15of each inspection unit30, the transfer stage18, the vacuum mechanism, and the like. The main controller of the control unit70causes the inspection system10to perform a predetermined operation based on a processing recipe stored in a storage medium built in the storage device or in a storage medium set in the storage device.

<Embodiments of Inspection Unit and Transfer Stage>

Next, embodiments of the inspection unit30and the transfer stage18will be described.

FIG. 3is a cross-sectional view showing configurations of the inspection unit30and the transfer stage18and mainly explains the inspection unit30.FIG. 4is a cross-sectional view for explaining the transfer stage18in detail.FIG. 5shows a state in which an aligner32and the chuck top29of the transfer stage are connected to each other.FIG. 6is a cross-sectional view taken along a line VI-VI′ inFIG. 5. InFIGS. 3 and 4, the left-right direction is the X-direction, the depth direction is the Y-direction, the up-down direction is the Z-direction, and the rotation direction about the Z-axis is the θ-direction.

FIG. 3shows a state in which the transfer stage18brings the wafer W into contact with the probe card19, and mainly shows the configuration of the inspection unit30including the tester15, the probe card19, and the like.

As shown inFIG. 3, in the inspection unit30, the tester15is integrally assembled, and has a motherboard21at a lower side thereof. The tester15has multiple inspection circuit boards (not shown) vertically fitted into the motherboard21.

A pogo frame20is disposed below the tester15to be fixed to a device frame (not shown). The probe card19is attached to the bottom of the pogo frame20. A cylindrical flange22capable of moving in the vertical direction with respect to the pogo frame20is engaged with the pogo frame20. A cylindrical bellows23is interposed between the pogo frame20and the flange22.

The probe card19includes a disk-shaped main body24, a plurality of electrodes (not shown) disposed substantially on the entire upper surface of the main body24, and a plurality of contact probes25(contact terminals) disposed to protrude downward from the bottom surface of the main body24. The electrodes are connected to the contact probes25corresponding thereto. Each of the contact probes25is brought into contact with an electrode pad or a solder bump of a device formed on the wafer.

The pogo frame20includes a substantially flat plate-shaped main body26, and pogo block insertion holes27that are multiple through-holes bored near the central portion of the main body26. Pogo blocks28including a plurality of pogo pins are inserted into the pogo block insertion holes27. The pogo blocks28are connected to an inspection circuit (not shown) of the tester15. Further, the pogo blocks28are brought into contact with multiple electrodes on the upper surface of the main body24of the probe card19attached to the pogo frame20, and allows currents to flow toward the contact probes25of the probe card19connected to the electrodes. In addition, the pogo block28allows currents flowing from the electric circuits of the semiconductor devices on the wafer W through the contact probes25to flow toward the inspection circuit.

The flange22has a cylindrical main body22aand a contact portion22bthat is an annular member formed below the main body22a. The flange22is disposed to surround the probe card19. As will be described later, the flange moves downward by its own weight so that the bottom surface of the contact portion22bis positioned below the tip ends of the contact probes25of the probe card19until the chuck top29is brought into contact with the flange22. The bellows23is made of a metal and can be extended and contracted in the vertical direction. A lower end and an upper end of the bellows23are in close contact with the upper surface of the contact portion22bof the flange22and the bottom surface of the pogo frame20, respectively.

A space31between the pogo frame20and the motherboard21is sealed with a sealing member31a. By evacuating the space31, the pogo frame20is attached to the motherboard21. A space between the pogo frame20and the probe card19is also sealed with a sealing member27a. By evacuating the space, the probe card19is attached to the pogo frame20. The evacuation is performed by a first vacuum mechanism61.

The transfer stage18includes the chuck top29that is a thick plate, and the aligner32. The wafer W is mounted on the upper surface of the chuck top29. The wafer W is vacuum-attracted to the chuck top29by a fourth vacuum mechanism64. In the case of transferring the wafer W, the chuck top29is connected to the aligner32and the chuck top29is vacuum-attracted to the aligner32by a fifth vacuum mechanism65. Accordingly, when the transfer stage18moves, it is possible to prevent the relative movement of the wafer W with respect to the transfer stage18. A stepped portion29ais formed at a peripheral portion of the upper surface of the chuck top29. A sealing member33is disposed at the stepped portion29a.

The chuck top29and the aligner32can be brought into contact with each other or separated from each other. When the chuck top29and the aligner32are separated from each other, the evacuation obtained by the fifth vacuum mechanism65is released. Each inspection unit30includes the chuck top29. As will be described later, when the inspection unit30performs inspection, the chuck top29is separated from the aligner32. When the wafer W is transferred, any one chuck top29is connected to the aligner32and comprised in the transfer stage18.

It is not necessary to perform vacuum attraction to hold the chuck top29or the wafer W. The chuck top29or the wafer W can be held in a different manner as long as the relative movement of the chuck top29and the wafer W with respect to the aligner32can be prevented. For example, the chuck top29or the wafer W can be held by electromagnetic attraction or clamping.

Since the transfer stage18is movable, the transfer stage18can be moved to a position below the probe card19of the inspection unit30. Thus, the wafer W mounted on the chuck top29can face the probe card19and can be moved toward the inspection unit30. When the chuck top29is brought into contact with the contact portion22bof the flange22and the wafer W is brought into contact with the probe card19, a space S is defined by the chuck top29, the flange22, the pogo frame20, and the probe card19. The space S is sealed by the bellows23and the sealing member33and is evacuated by the second vacuum mechanism62. Further, the inside of the sealing member33is evacuated by a third vacuum mechanism63. Accordingly, the chuck top29is held by the probe card19, and the wafer W mounted on the chuck top29is brought into contact with the probe card19. At this time, the electrode pads or the solder bumps of the devices on the wafer W are brought into contact with the contact probes25of the probe card19. In the wafer inspection system10, the movement of the transfer stage18is controlled by the control unit70, and the control unit70controls the position or the amount of movement of the transfer stage18.

FIG. 4shows the transfer stage18in a state where the chuck top29is separated from the aligner32. As shown inFIG. 4, the aligner32includes an X base34, an X guide35, a plurality of X blocks36, a Y base37, a Y guide38, a plurality of Y blocks39, a Z base40, a Z block41, and a chuck base42. The X base34is a plate-shaped member, and the X guide35has a rail shape extending on the X base34in the X direction. The X blocks36can move in the X direction while being engaged with the X guide35. The Y base37is a plate-shaped member and is supported by the X blocks36. The Y guide38has a rail shape extending on the Y base37in the Y direction. The Y blocks39can move in the Y direction while being engaged with the Y guide38. The Z base40is a plate-shaped member and is supported by the Y blocks39. The Z block41moves in the vertical direction while penetrating through the Z base40. The chuck base42is disposed on the Z block41.

As the X blocks36move in the X direction, the Y base37can move in the X direction with respect to the X base34. As the Y blocks39move in the Y direction, the Z base40can move in the Y direction with respect to the Y base37and the X base34. The Z block41can vertically move the chuck base42using a plurality of elevating mechanisms (not shown) such as a ball screw mechanism or the like. The chuck base42can be rotated in the θ direction by a rotation mechanism (not shown).

The chuck base42has a chuck top attracting surface52at the center of the upper surface thereof. The chuck top29has a bottom plate53at the bottom thereof. The chuck top29is vacuum-attracted in a state where the bottom surface of the bottom plate53and the chuck top attraction surface52of the chuck base42are in contact with each other. Accordingly, the chuck top29is mounted on and attached to the aligner32.

A plurality of height sensors54are arranged at a peripheral portion of the upper surface of the chuck base42. A plurality of detection plates56are arranged at a peripheral portion of the bottom surface of the chuck top29to correspond to the height sensors54.

Multiple (three in this example (seeFIG. 6)) radially expandable positioning pins55are disposed at the outer side of the height sensors54on the upper surface of the chuck base42. Multiple (three) pin insertion members57are disposed at the outer side of the detection plates56on the bottom surface of the chuck top29to correspond to the positioning pins55. The positioning pins55and the pin insertion members57are arranged at equal intervals on the circumferences about the centers of the chuck base42and the chuck top29, respectively. The positioning pins55and the pin insertion members57constitute an aligning mechanism. A cylindrical insertion hole57ais vertically formed at the pin insertion member57. The insertion hole57ahas a diameter greater than a diameter of the positioning pin55that is not radially expanded. In other words, the pin insertion member57has an inner wall that is a vertical circumferential surface. When the aligner32is connected to the chuck top29, the chuck top29and the aligner32are aligned by the positioning pins55and the pin insertion members57.

At this time, if the chuck base42is raised, the positioning pins55that are not radially expanded are inserted into the insertion holes57aof the pin insertion members57. If the chuck base42is raised further, the state shown inFIG. 5is obtained. In other words, the bottom plate53and the chuck top attraction surface52are brought into contact with each other, so that the chuck top29and the aligner32are aligned in the vertical direction.

FIG. 7Ashows an example of the positioning pin. As shown inFIG. 7A, the positioning pin55has a hollow main body58and a radially expandable portion59accommodated in the main body58. In this state, if air is supplied into the main body58through an air line (air supply mechanism)55a, the radially expandable portion59projects outward from a notched portion (not shown) formed at the main body58as shown inFIG. 7Bso that the positioning pin55can be expanded radially. When the air supply is stopped, the radially expandable portion59is returned to the inside of the main body58by an elastic member such as a spring or the like. After the positioning pin55that is not radially expanded is inserted into the insertion hole57aof the pin insertion member57, the radially expandable portion59projects and the positioning pin55is radially expanded. Accordingly, the chuck base42and the chuck top29are aligned in the horizontal direction and the rotation direction, as shown inFIG. 8.

As shown inFIG. 4, the aligner32has an upper checking camera72for checking a degree of inclination of the probe card19or the pogo frame20. The upper checking camera72is attached to the Z block41. The aligner32has a plurality of elevating mechanisms for raising and lowering the chuck base42as described above. By adjusting the lifting amounts of the elevating mechanisms based on the information of the upper checking camera72, the degree of inclination of the chuck base42can be adjusted.

<Configuration Used for Replacement of Probe Card>

In the inspection system10, when the probe card19is replaced, an old probe card19is returned to the loader port17cand a new probe card19is mounted by the transfer stage18. At this time, a mounting jig80is used to protect the contact probes25of the probe card19as shown inFIG. 9. The mounting jig80includes a plate81having a diameter greater than that of the probe card19, a cylindrical leg portion82attached to the peripheral portion of the bottom surface of the plate81, and a cylindrical probe card support portion83attached to the peripheral portion of the upper surface of the plate81.

At this time, in order to attach the probe card19to the accurate portion of the pogo frame20, the leg portion82is positioned on the chuck top29and fixed by vacuum attraction. In addition, the probe card19is fixed to the probe card support portion83by vacuum attraction. The pneumatic circuit for vacuum attracting the leg portion82includes gas exhaust passages91and95, a coupler93, and a sixth vacuum mechanism66. The gas exhaust passage91is disposed at the chuck top29. The gas exhaust passage95is disposed at the aligner32. The coupler93connects the gas exhaust passage91and the gas exhaust passage95. The sixth vacuum mechanism66is connected to the gas exhaust passage95. A pneumatic circuit for attracting the probe card19to the probe card support portion83includes gas exhaust passages84,92, and96, a coupler94, and a seventh vacuum mechanism67. The gas exhaust passage84extends from the probe card support portion83to the plate81and the bottom surface of the leg portion82. The gas exhaust passage92is formed at the chuck top29to be continuous to the gas exhaust passage84. The gas exhaust passage96is disposed at the aligner32. The coupler94connects the gas exhaust passage92and the gas exhaust passage96. The seventh vacuum mechanism67is connected to the gas exhaust passage96.

The couplers93and94are opened for evacuation when the gas exhaust passages95and96are connected thereto, respectively, and the couplers93and94are closed when the gas exhaust passages95and96are disconnected therefrom, respectively.

In the pneumatic circuits, both of the sixth vacuum mechanism66and the seventh vacuum mechanism67are disposed at the aligner32side. Therefore, as shown inFIG. 10, when the chuck top29is attracted to the flange22and the aligner32is separated from the chuck top29, the gas exhaust passages95and96are separated from the couplers and94, respectively, and the couplers93and94are closed. Accordingly, the evacuation of the space S is not affected by the second vacuum mechanism62.

In a conventional case, two pneumatic circuits used for replacing the probe card were disposed on the chuck top side. Therefore, it is required to provide the pneumatic circuits at the chuck tops of which number corresponds to the number of the inspection units30. On the other hand, in this example, the pneumatic circuits are disposed on the aligner side so that the gas exhaust passages on the chuck top side and the gas exhaust passages on the aligner side can be brought into contact with each other or separated from each other by the couplers. Accordingly, the number of pneumatic circuits in each stage can be reduced. For example, when there are six inspection units30in each stage as in this example, 12 pneumatic circuits are required in the conventional case for the six inspection units30. However, in this example, the number of the pneumatic circuits can be reduced to two.

Next, the operation of the inspection system of the present embodiment will be described.

The wafer W is received from the FOUP of the wafer loading/unloading port17aby the transfer stage18, and the transfer stage18in which the wafer W is mounted on the chuck top29is moved to a position below a predetermined inspection unit30(tester15).

In this state, first, the chuck top29is aligned in the horizontal direction by the aligner32as shown inFIG. 11A. Then, as shown inFIG. 11B, the chuck base42is raised by the Z block41of the aligner32to bring the wafer W into contact with the contact probes25of the probe card19and attract the chuck top29to the contact portion22bof the flange22. At this time, the chuck top29is attracted by evacuating the space S surrounded by the chuck top29, the flange22, the pogo frame20, and the probe card19. Accordingly, the positional relationship between the chuck top29and the probe card19is maintained, and the wafer W remains in contact with the contact probes25of the probe card19. At this time, a vacuum level is controlled such that a pressing force applied to the wafer W by the chuck top29due to the evacuation of the space S becomes greater than a reaction force applied to the chuck top29by the contraction of the bellows23.

Next, as shown inFIG. 11C, in a state where the space S is evacuated, the vacuum attraction between the aligner32and the chuck top29is released and the aligner32is separated from the chuck top29. In this state, the electrical characteristics of the devices formed on the wafer W are inspected. At this time, a negative pressure caused by the evacuation is not applied to the wafer W due to the presence of the chuck top29and, thus, the wafer W is not warped.

The aligner32separated from the chuck top29is moved to a position below another inspection unit30(tester15) where the inspection of the wafer is completed. Then, the chuck base42is raised to connect the aligner32to the chuck top29attracted and held on the inspection unit30. Accordingly, the transfer stage18is assembled, and the wafer W on the chuck top29is transferred to the FOUP of the wafer transfer port17a. A new wafer W is mounted on the chuck top29of the transfer stage18and transferred to the same inspection unit30. Next, the chuck top29is raised in the above-described manner to bring the wafer W into contact with the contact probes25of the probe card19. Then, the chuck top29is attracted so that the inspection of electrical characteristics can be performed. The above-described operations are repeated for the number of wafers W in the FOUP.

In the case of connecting the chuck top29and the aligner32, it is required to align the chuck top29and the aligner32with high accuracy. In Patent Document 3, as shown inFIG. 12A, a plurality of positioning pins155are disposed on the upper surface of the chuck base42of the aligner32, and a plurality of positioning blocks157, each having a V-shaped groove, are disposed on the bottom surface of the chuck top29to correspond to the positioning pins155. By engaging the positioning pins155with the positioning blocks157, the alignment in the vertical direction, the horizontal direction, and the rotation direction is simultaneously performed.

By using the above technique, the alignment may be performed efficiently. However, the above technique is disadvantageous in that the positioning pins155are aligned on the inclined surfaces of the V-shaped grooves of the positioning blocks157, as shown inFIG. 12B, which may result in variation in parallelism between the aligner32and the chuck top29or the like. Therefore, the chuck base42of the aligner32may be shaken after the chuck top29is mounted on the aligner32. However, it is still insufficient to avoid such a problem.

Therefore, in the present embodiment, the radially expandable positioning pins55are disposed at the peripheral portion of the upper surface of the chuck base42in the aligner32. Further, the pin insertion members57, each having an insertion hole57aof which diameter is greater than that of the positioning pin that is not radially expanded, is disposed at the peripheral portion of the bottom surface of the chuck top29to correspond to the positioning pins55. The chuck top29and the aligner32are aligned by the positioning pins55and the pin insertion members57.

Specifically, first, the aligner32is roughly aligned in the horizontal direction based on the coordinates provided by the control unit70. Then, the chuck base42of the aligner32is raised, and the positioning pins55that are not radially expanded are inserted into the insertion holes57aof the pin insertion members57which have diameters greater than those of the positioning pins55. In this state, the chuck base42is further raised to bring the chuck top attraction surface52into contact with the bottom surface of the bottom plate53in the chuck top29as described with reference toFIG. 5. Accordingly, the chuck top29and the aligner32are aligned in the vertical direction.

Next, as described with reference toFIGS. 7B and 8, the radially expandable portions59project outward from the main bodies58of the positioning pins55and, thus, the positioning pins55are radially expanded. Accordingly, even if the horizontal position of the aligner32is displaced, the displacement is corrected by the radial expansion of the positioning pins55, and the chuck top29and the aligner32are aligned in the horizontal direction and the rotational direction.

As described above, the chuck top29and the aligner32are aligned in the vertical direction, and then in the horizontal direction and the rotation direction. Therefore, it is possible to avoid the drawback of the technique disclosed in Patent document 3, such as variation in the parallelism between the aligner32and the chuck top29which occurs when the alignment in the vertical direction and that in the horizontal direction are performed simultaneously by the positioning pins155and the positioning blocks157. Accordingly, the aligner32and the chuck top29can be reliably aligned with high accuracy.

In this case, the projecting direction of the radially expandable portion59is important. When three positioning pins55and three pin insertion members57are arranged at equal intervals on the same circumference, the radially expandable portions59project in the directions shown inFIGS. 13A to 13C. InFIG. 13A, the three positioning pins55are radially expanded outward. InFIG. 13B, the three positioning pins545are radially expanded inward. InFIG. 13C, the three positioning pins55are radially expanded in the circumferential direction. Although the alignment can be performed with high accuracy in all examples, the example shown inFIG. 13Cis most desirable. In the case of radially expanding the positioning pins55, even if each of the timing of radial expansion is set to be the same, the timing may be shifted slightly. Even in that case, the alignment can be performed more accurately in the example shown inFIG. 13C. At least one of the projecting directions of the radially expandable portions59of the three positioning pins55may be different from the others.

The alignment can also be performed by two positioning pins55and two pin insertion members57. In that case, however, the projecting directions of the radially expandable portions59are limited. For example, the positioning cannot be performed when both of the radially expandable portions59of the two positioning members55project in the radial direction or in the circumferential direction. However, the positioning can be performed when one of the radially expandable portions59projects in the radial direction and the other radially expandable portion59projects in the circumferential direction, as shown inFIG. 14. The number of the positioning pins55and the pin insertion members57may be four or more.

The radially expandable portion59of the positioning pin55may be projected by a mechanical device or an electrical device, other than air. The mechanical device may be a device for holding the radially expandable portion59in the main body58using a holding device in a state where an elastic body such as a spring or the like is compressed and releasing the holding device so that the radially expandable portion59projects outward from the main body58.

As shown inFIG. 15, the diameter of the lower end portion of the insertion hole57aof the pin insertion member57, i.e., the diameter of the positioning pin insertion port, is set to be greater than that of the vertical part so that the inclined portion57bcan be formed at the lower end portion of the pin insertion member57. Accordingly, even if the positioning pin55is displaced considerably, the positioning pin55can be lifted along the inclined portion57band reliably inserted into the insertion hole57a.

The above-described embodiments are illustrative in all respects and are not restrictive. The above-described embodiments can be embodied in various forms. Further, the above-described embodiments may be omitted, replaced, or changed in various forms without departing from the scope of the appended claims and the gist thereof.

For example, in the above-described embodiments, the radially expandable portions accommodated in the main bodies project outward from the main bodies and, thus, the positioning pins are radially expanded. However, the radial expansion can be performed in a different manner without being limited thereto. For example, the outer surface of the positioning pin may be divided into multiple parts in the vertical direction, and the divided parts may be mechanically moved outward so that the entire pin is radially expanded.

The above-described embodiments have described an example in which the positioning pins are disposed on the upper surface of the aligner (the upper surface of the chuck base) and the pin insertion members are disposed on the bottom surface of the chuck top. However, the pin insertion members may be disposed on the upper surface of the aligner, and the positioning pins may be disposed on the bottom surface of the chuck top.

Further, the above-described embodiments have described the inspection system including multiple inspection apparatuses, each having the probe card and the tester. In this inspection system, while a wafer is being transferred to one inspection apparatus by the transfer stage having the aligner and the chuck top, another wafer can be inspected by another inspection apparatus. However, the present disclosure is not limited thereto, and can be applied to any inspection apparatus including a transfer stage in which a chuck top and an aligner can be brought into contact with each other or separated from each other.

DESCRIPTION OF REFERENCE NUMERALS