JP6361975B2 - Prober - Google Patents

Description

  The present invention relates to a prober that performs electrical inspection of a plurality of chips formed on a semiconductor wafer.

  In the semiconductor manufacturing process, various processes are performed on a thin disk-shaped semiconductor wafer to form a plurality of chips (dies) each having a semiconductor device (device). Each chip is inspected for electrical characteristics, then separated by a dicer, and then fixed to a lead frame and assembled. The inspection of the electrical characteristics is performed by a wafer test system composed of a prober and a tester. The prober fixes the wafer to the wafer chuck and brings the probe into contact with the electrode of each chip. The tester is electrically connected to the probe, and measures the characteristics by applying current and voltage to each chip for electrical inspection.

  Semiconductor devices (devices) such as power transistors, power MOSFETs (field effect transistors), IGBTs (insulated gate bipolar transistors), LEDs, and semiconductor lasers generally have electrodes (chip surface electrodes) formed on the surface of a wafer. An electrode (chip back electrode) is also formed on the back surface of the wafer. For example, in an IGBT, a gate electrode and an emitter electrode are formed on the front surface of a wafer, and a collector electrode is formed on the back surface of the wafer.

  In order to perform wafer level inspection on a wafer in which a plurality of chips having electrodes are formed on both surfaces of the wafer as described above, the wafer chuck holds the back surface of the wafer in contact and acts as a measurement electrode for the tester. A supporting surface (wafer mounting surface) is provided. This support surface is electrically connected to the tester via a cable drawn from the wafer chuck. When inspection is performed, various measurements are performed in a state where the wafer is held on the wafer chuck and the probe is in contact with the electrode (chip surface electrode) of each chip formed on the surface of the wafer. Yes.

  However, since the cable connecting the wafer chuck and the tester is arranged in a state of being routed inside and outside the housing via a connection connector provided on the side surface or the back surface of the housing constituting the prober. The length is usually about 1 to 3m. For this reason, the electrical path formed between the chip back electrode and the tester becomes longer, and the resistance and inductance increase, resulting in measurement errors in high frequency measurement and dynamic measurement, and wafer level inspection with the required accuracy. There is a problem that cannot be performed properly.

  In order to solve such a problem, for example, Patent Document 1 discloses a chuck lead plate provided so as to face a conductive support surface of a wafer chuck, and a pogo pin fixed to a peripheral portion of the wafer chuck. , An inspection apparatus provided with. According to this inspection apparatus, since the electrical path formed between the chip back electrode and the tester is configured via the pogo pin and the chuck lead plate, the electrical path is generated in the electrical path as compared with the conventional configuration described above. Resistance and inductance can be reduced.

  However, in the inspection apparatus described in Patent Document 1, since the pogo pins are fixed to the wafer chuck, the length of the electrical path between the chip back electrode and the tester varies depending on the position of the chip to be inspected on the wafer. . For example, the length of the electrical path is different between the case of inspecting a chip existing near the center of the wafer and the case of inspecting a chip existing near the edge of the wafer. For this reason, the resistance and impedance generated in the electrical path change depending on the position of the chip to be inspected on the wafer, which adversely affects high frequency measurement and dynamic measurement, and the wafer level inspection cannot be performed with high accuracy. There is a problem.

  In order to solve such a problem, the applicant of the present application is configured to electrically contact a contactor fixed at a position facing the stage member with respect to the conductive stage member that moves integrally with the wafer chuck. Proposed probers (see Patent Document 2). According to this prober, the resistance and impedance in the electrical path formed between the chip back electrode and the tester are small and less fluctuating without being influenced by the position of the chip to be inspected on the wafer. Dynamic measurement can be performed stably, and wafer level inspection can be performed with high accuracy.

JP2011-138865A JP 2014-110381 A

  By the way, in the prober proposed by the applicant of the present application, the stage member moves integrally with the wafer chuck, so the height of the contact is adjusted according to the height of the wafer chuck (contact height) at the time of probe contact. There is a need to. In particular, there are many types of probe holders represented by, for example, probe cards, etc., and the length of the probe varies. In addition, the height of the contact must be adjusted, which causes a reduction in work efficiency and an increase in cost. In addition, if the height of the contact is not properly adjusted, the contact pressure of the contact with the stage member will vary, and the resistance and impedance in the electrical path formed between the chip back electrode and the tester will change. As a result, the accuracy of wafer level inspection is reduced.

  The present invention has been made in view of such circumstances, and can provide a prober that can improve work efficiency and reduce costs, and can perform high-frequency measurement and wafer level inspection of dynamic characteristics with high accuracy. The purpose is to provide.

  In order to achieve the above object, the prober according to the first aspect of the present invention is a wafer chuck for holding a wafer on which a plurality of chips having electrodes on both sides are formed, and the chip back electrode formed on the back surface of the wafer A wafer chuck having a conductive support surface in contact with the wafer, a moving rotation mechanism for moving and rotating the wafer chuck, and a chip surface electrode formed on the surface of the wafer in contact with the chip surface electrode to connect to a tester terminal A probe holding unit having a probe, a probe position detection camera for detecting the height of the probe tip of the probe holding unit, a wafer alignment camera for detecting the position of the chip surface electrode of the wafer held by the wafer chuck, and wafer alignment Based on the first lifting mechanism that moves the camera up and down and the detection result of the probe position detection camera, A control unit that controls the first elevating mechanism so that the height of the lobe tip and the focal position of the wafer alignment camera are the same height, and is formed parallel to the support surface and electrically connected to the support surface. The stage member has a conductive stage surface and moves integrally with the wafer chuck, and can move integrally with the wafer alignment camera. The chip back surface electrode is electrically connected to the tester by contacting the stage surface. A conductive contact to be connected.

  According to this aspect, since the conductive contact is configured to be movable integrally with the wafer alignment camera, the height of the probe tip (probing height) and the focal position of the wafer alignment camera (alignment height) By moving the wafer alignment camera in the vertical direction so that the heights are the same, the height of the tip of the conductive contact is always in a fixed positional relationship with the height of the tip of the probe. Therefore, even when the length of the probe changes when the probe holding part is replaced, it is not necessary to adjust the height of the conductive contact, so that the work efficiency can be improved and the cost can be reduced. In addition, even if the probing height changes, the contact pressure with respect to the conductive contact of the stage member is always constant, so changes in resistance and inductance due to variations in contact pressure can be suppressed, and high-frequency measurement and dynamic measurement can be performed. It is possible to perform stably, and to perform wafer level inspection with high accuracy.

  The prober according to a second aspect of the present invention includes, in the first aspect, a second elevating mechanism that changes a relative height of the conductive contact with respect to the wafer alignment camera.

  According to this aspect, even when the wafer chuck moves to the alignment region where the wafer alignment camera is arranged, the relative height of the conductive contact with respect to the wafer alignment camera can be changed by the second lifting mechanism. Thus, it is possible to prevent the conductive contact from interfering with the wafer chuck or the wafer held thereon.

  In the prober according to the third aspect of the present invention, in the first aspect or the second aspect, the stage member is configured separately from the wafer chuck, and the stage surface and the support surface are electrically connected via the wiring member. The

  This embodiment is a preferred embodiment of the present invention. According to this aspect, since the stage member is thermally separated from the wafer chuck, even when the wafer chuck is heated and cooled during the wafer level inspection, the temperature change of the wafer chuck is not easily transferred to the stage member, and the heat insulation effect Therefore, energy efficiency is good and thermal deformation of the stage member is prevented. As a result, the conductive contact can always come into contact with the stage surface of the stage member with a constant contact pressure without changing the contact position (the height in the Z direction) of the conductive contact with the stage surface of the stage member. it can. Therefore, it is possible to improve the measurement accuracy and reliability of the wafer level inspection without being affected by the temperature change of the wafer chuck.

  In the prober according to the fourth aspect of the present invention, in the first aspect or the second aspect, the stage member is configured integrally with the wafer chuck.

  This aspect shows one of the specific aspects in the present invention. That is, the stage member may be configured integrally with the wafer chuck, and the effect of the first aspect described above can be obtained.

  The prober according to a fifth aspect of the present invention is the prober according to any one of the first to fourth aspects, wherein the stage member is a conductive contact when the probe contacts the chip surface electrode in the movable range of the wafer chuck. Is configured such that it can always contact the stage surface.

  According to this aspect, since the contact is always capable of contacting the stage surface of the stage member when the probe contacts the chip surface electrode regardless of the position of the wafer chuck, the wafer level inspection is performed stably and reliably. It becomes possible.

  According to the present invention, it is possible to improve work efficiency and reduce costs, and to perform high-frequency measurement and wafer level inspection of dynamic characteristics with high accuracy.

Schematic configuration diagram showing a wafer test system to which the present invention is applied Plan view showing relationship between wafer chuck and stage member Flow chart showing the flow of wafer level inspection The figure for demonstrating each process shown in FIG. The figure for demonstrating each process shown in FIG. The figure for demonstrating each process shown in FIG. The figure for demonstrating each process shown in FIG. The figure for demonstrating each process shown in FIG. Diagram showing the relationship between alignment height and probing height when the probe card has different probe heights Explanatory drawing of a 1st modification Explanatory drawing of a 2nd modification

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a schematic configuration diagram showing a wafer test system to which the present invention is applied. As shown in the figure, a wafer test system 100 is connected to a prober 10 that makes a probe 25 contact an electrode of each chip on a wafer W, and the probe 25, and a current is supplied to each chip for electrical inspection. And a tester 30 for applying a voltage and measuring characteristics.

  The prober 10 includes a base 11, a moving base 12, a Y-axis moving table 13, an X-axis moving table 14, a Z-axis moving / rotating unit 15, a wafer chuck 16, and a probe position. Detection camera 18, wafer alignment camera 19, head stage 22, card holder 23 provided on head stage 22, probe card 24 attached to card holder 23, and control unit 60 that controls each part of prober 10 Have. A probe 25 is provided on the probe card 24.

  The movement base 12, the Y-axis movement table 13, the X-axis movement table 14, and the Z-axis movement / rotation unit 15 constitute a movement rotation mechanism that rotates the wafer chuck 16 in the three axis directions and around the Z axis. Since the moving and rotating mechanism is widely known, the description thereof is omitted here.

  The wafer chuck 16 holds a wafer W on which a plurality of chips are formed by vacuum suction, and a conductive support surface (wafer mounting surface) 16a that acts as a measurement electrode of the tester 30 is provided on the upper surface thereof. It is done. Further, inside the wafer chuck 16, heating as a heating / cooling source is performed so that the electrical characteristics can be inspected in a high temperature state, for example, a maximum of 150 ° C. or a low temperature state, for example, −40 ° C. / Cooling mechanism (heating / cooling mechanism) is provided. As the heating / cooling mechanism, a known appropriate heater / cooler can be adopted, for example, a double layer structure of a heating layer of a surface heater and a cooling layer provided with a passage for cooling fluid, Various devices such as a heating / cooling device having a single layer structure in which a cooling pipe around which a heater is wound are embedded in a heat conductor are conceivable. Further, instead of electrical heating, a thermal fluid may be circulated, and a Peltier element may be used.

  The wafer chuck 16 is mounted on the Z-axis moving / rotating unit 15 and can be moved in the three-axis directions (X, Y, Z directions) by the above-described moving and rotating mechanism, and the rotation direction around the Z-axis. It can be rotated in the (θ direction).

  A probe card 24 is disposed above the wafer chuck 16 on which the wafer W is held. The probe card 24 is mounted with a card holder 23 attached to the opening of the head stage 22 that constitutes the top plate of the housing of the prober 10.

  The probe card 24 has a probe 25 arranged according to the electrode arrangement of the chip to be inspected, and is exchanged according to the chip to be inspected. The probe card 24 is an example of a probe holding unit.

  The tester 30 includes a tester body 31 and a contact ring 32 provided on the tester body 31. The probe card 24 is provided with a terminal connected to each probe 25, and the contact ring 32 has a spring probe arranged so as to contact the terminal. The tester body 31 is held with respect to the prober 10 by a support mechanism (not shown).

  The probe position detection camera 18 is mounted on the X-axis moving table 14 and can be moved in the XY direction integrally with the wafer chuck 16 by the X-axis moving table 14 and the Y-axis moving table 13. The probe position detection camera 18 images the probe 25 of the probe card 24 from below and detects the tip position of the probe 25. The position (X and Y coordinates) of the tip of the probe 25 in the horizontal plane is detected by the coordinates of the camera, and the position in the vertical direction (Z direction), that is, the height of the tip of the probe 25 (probing height) is the focal position of the camera. Is detected. A detection result by the probe position detection camera 18 is input to the control unit 60.

  The wafer alignment camera 19 is disposed in an alignment region adjacent to the probe region where the probe card 24 is disposed. The wafer alignment camera 19 is supported by a support column (not shown) and can be moved in the Z direction (vertical direction) by a camera lifting mechanism (first lifting mechanism) 40. The camera elevating mechanism 40 may be a known linear moving mechanism, and is configured by, for example, a linear guide mechanism, a ball screw mechanism, and the like, and is driven by an output from the control unit 60. The wafer alignment camera 19 captures an image of the wafer W held by the wafer chuck 16 from above and detects the position of a chip electrode (chip surface electrode) formed on the surface of the wafer W. The detection result by the wafer alignment camera 19 is input to the control unit 60. The control unit 60 uses a known image processing technique on the basis of the information obtained by the wafer alignment camera 19 and the position information of the tip of the probe 25 obtained by the probe position detection camera 18, and the probe 25 and the wafer. The two-dimensional position alignment in the XY plane of the W chip electrode (chip surface electrode) is automatically performed.

  In addition to the above-described configuration, the prober 10 according to the present embodiment further includes a stage member 50 formed of a disc-shaped separation structure that is configured separately from the wafer chuck 16.

  The stage member 50 is disposed at a position adjacent to the wafer chuck 16, is connected and fixed to the Z-axis moving / rotating unit 15 via an L-shaped connecting member 52, and is integrated with the wafer chuck 16 in three axes. It can move in the direction (X, Y, Z direction).

  Moreover, as a material which comprises the stage member 50, the material with a small thermal expansion coefficient, such as ceramics, is suitable, for example. By configuring the stage member 50 with a material having a small coefficient of thermal expansion, thermal deformation of the stage member 50 can be prevented even when the wafer chuck 16 is heated and cooled during wafer level inspection. As a result, the measurement accuracy and reliability of the wafer level inspection can be improved without being affected by the temperature change of the wafer chuck 16.

  On the upper surface of the stage member 50, a conductive stage surface 50 a that can contact a conductive contact 70 described later is provided. As shown in FIG. 2, the stage surface 50a has the same planar shape (circular shape) as the support surface 16a of the wafer chuck 16, and their areas (planar areas) are equal to each other. Note that the stage surface 50a may have a larger area (planar area) than the support surface 16a of the wafer chuck 16 and may have a shape other than a circle.

  A plurality of wirings 64 (wiring members) are provided between the stage member 50 and the wafer chuck 16. In this example, three wirings 64 are provided. One end of each wiring 64 is electrically connected to the stage surface 50 a of the stage member 50, and the other end thereof is electrically connected to the support surface 16 a of the wafer chuck 16. That is, the electrical connection between the stage surface 50 a of the stage member 50 and the support surface 16 a of the wafer chuck 16 is ensured by the plurality of wires 64.

  Returning to FIG. 1, a conductive contact 70 is provided at a position facing the stage member 50. The conductive contact 70 is formed of, for example, a conductive thin needle (spring pin) having a spring property, and is electrically connected to the tester body 31 via a cable 76.

  The conductive contact 70 is held and fixed at a predetermined height position by a holder 74 described later, and when the wafer chuck 16 is raised and the probe 25 comes into contact with the chip surface electrode of the wafer W (that is, the wafer chuck 16). Is moved to the contact height), it makes electrical contact with the stage surface 50a of the stage member 50 at a predetermined contact pressure. Thus, when various measurements are performed in a state where the probe 25 is in contact with the chip surface electrode formed on the surface of the wafer W, the chip back electrode formed on the back surface of the wafer W is attached to the wafer chuck 16 (support surface 16a). ), The wiring 64, the stage member 50 (stage surface 50 a), the conductive contact 70, and the cable 76 to be electrically connected to the tester body 31.

  In the present embodiment, the conductive contact 70 is attached to the wafer alignment camera 19 and is configured to be movable integrally with the wafer alignment camera 19. Specifically, the wafer alignment camera 19 is provided with a Z table 72 that can be moved in the Z direction (vertical direction) by a contact elevating mechanism (second elevating mechanism) 78. A holder 74 for holding and fixing the sexual contact 70 is attached. Therefore, the conductive contact 70 can be moved in the Z direction integrally with the wafer alignment camera 19 by the camera lifting mechanism 40 and the relative contact of the conductive contact 70 with respect to the wafer alignment camera 19 by the contact lifting mechanism 78. It is possible to change the height. The contact elevating mechanism 78 is configured by a known linear moving mechanism such as a linear guide mechanism and a ball screw mechanism, for example, like the camera elevating mechanism 40 described above.

  Next, wafer level inspection by the wafer test system 100 of the present embodiment will be described with reference to FIGS. FIG. 3 is a flowchart showing the flow of wafer level inspection. 4-8 is a figure for demonstrating each process shown in FIG. 4 to 8 show only main parts of the wafer test system. The conductive contact 70 is movable relative to the wafer alignment camera 19 between a retracted position (upper position) and a contact position (lower position) by the contact elevating mechanism 78. The conductive contact 70 Is moved in advance to the contact position, the tip of the conductive contact 70 (the tip on the stage member 50 side) is adjusted in advance so as to coincide with the height of the focus position of the wafer alignment camera 19 (alignment height). To do.

(Step S10: probing height detection step)
First, as shown in FIG. 4, the probe position detection camera 18 is moved together with the wafer chuck 16 so that the probe position detection camera 18 is positioned below the probe card 24, and the probe position detection camera 18 increases the height of the tip of the probe 25. The height (probing height) h0 is detected. A detection result by the probe position detection camera 18 is input to the control unit 60.

(Step S12: Wafer transfer process)
Next, a wafer W to be inspected is loaded onto the wafer chuck 16 by a wafer loading mechanism (not shown), and the wafer W is held on the wafer chuck 16.

(Step S14: Alignment height adjustment process)
Next, as shown in FIG. 5, the controller 60 moves the wafer chuck 16 so that the wafer W is positioned under the wafer alignment camera 19 while holding the wafer W on the wafer chuck 16. When the height of the focal position of the wafer alignment camera 19 (alignment height) is h1 by controlling the camera lifting mechanism 40 of the wafer alignment camera 19, the wafer alignment camera 19 is set by Δh (= h1-h0). Is moved in the Z direction. Accordingly, as shown in FIG. 6, the probing height h0 and the alignment height h1 are the same.

  Subsequently, as shown in FIG. 7, the controller 60 controls the wafer chuck so that the wafer W held on the wafer chuck 16 is positioned at the alignment height (that is, the height of the focal position of the wafer alignment camera 19). 16 is moved in the Z direction. At this time, in order to prevent interference with the wafer W held on the wafer chuck 16 or its upper surface (support surface 16a), the control unit 60 moves the Z table 72 in the Z direction by the contact elevating mechanism 78 to conduct the conductive operation. The conductive contact 70 is moved to a retracted position where it does not contact the wafer chuck 16 or the wafer W.

(Step S16: Wafer alignment step)
Next, the position of the chip electrode (chip surface electrode) on the wafer W is detected by the wafer alignment camera 19. It is not necessary to detect the positions of all the electrodes of one chip, and the positions of several electrodes may be detected. Further, it is not necessary to detect the electrodes of all the chips on the wafer W, and the positions of the electrodes of several chips are detected. The detection result by the wafer alignment camera 19 is input to the control unit 60.

  Subsequently, the control unit 60 uses a known image processing technique on the basis of the information obtained by the wafer alignment camera 19 and the position information of the tip of the probe 25 obtained by the probe position detection camera 18. 2 and the two-dimensional alignment in the XY plane of the electrode of the chip of the wafer W (chip surface electrode) is automatically performed. That is, the control unit 60 detects the position of the probe 25 and the position of the chip electrode on the wafer W, and then moves the Z-axis movement / rotation unit 15 so that the arrangement direction of the chip electrode coincides with the arrangement direction of the probe 25. As a result, the wafer chuck 16 is rotated.

(Step S18: Probing process)
Next, the controller 60 once lowers the wafer chuck 16 slightly in the Z direction, and then the wafer W held by the wafer chuck 16 is positioned below the probe card 24 as shown in FIG. The wafer chuck 16 is moved. Thereafter, the wafer chuck 16 is raised in the Z direction to the height immediately before the wafer chuck 16 is lowered in the Z direction, that is, the tip height (probing height) of the probe 25 which is the same height as the alignment height. These electrodes are brought into contact with the probe 25.

  At this time, the stage member 50 disposed adjacent to the wafer chuck 16 moves to a position facing the conductive contact 70 together with the wafer chuck 16. Further, the control unit 60 controls the contact elevating mechanism 78 in conjunction (synchronization) with the movement of the wafer chuck 16 so that the relative position of the conductive contact 70 with respect to the wafer alignment camera 19 becomes the contact position. The sex contact 70 is moved. As a result, the conductive contact 70 comes into contact with the stage surface 50a of the stage member 50 with a predetermined contact pressure, and the chip back surface electrode formed on the back surface of the wafer W becomes the wafer chuck 16 (support surface 16a), the wiring 64, The stage member 50 (stage surface 50 a), the conductive contact 70, and the cable 76 are electrically connected to the tester body 31. Then, current and voltage are applied to the chip from the tester body 31 to measure the characteristics.

  When the inspection of this chip is completed, the wafer W and the probe 25 are once separated, and other chips move so as to be positioned under the probe 25, and the same operation is performed. Hereinafter, each chip is selected and inspected. When the inspection of all the designated chips on the wafer is completed, the inspection of one wafer is completed.

  In this way, when all the chips on the wafer W have been inspected, the inspection of the wafer W is completed, the inspected wafer W is unloaded, the next wafer W to be inspected is loaded, and the above operation is performed. I do.

  Next, the effect of this embodiment will be described.

  FIG. 9 is a diagram showing the relationship between the alignment height and the probing height when the length of the probe 25 of the probe card 24 is different. (A) shows the case where the length of the probe 25 is short, and (b) shows the case where the length of the probe 25 is long.

  In this embodiment, as shown in FIGS. 9A and 9B, even when the length of the probe 25 is changed when the probe card 24 is replaced, the probing height and the alignment height are the same. In addition, since the wafer alignment camera 19 moves, the alignment of the tip of the probe 25 after the alignment of the wafer W and the electrode pad of the chip of the wafer W only needs to be performed within the XY plane, and an error in the Z direction can be achieved. Can be reduced. On the other hand, when the probing height and the alignment height are different from each other, the alignment in the Z direction must be performed after the alignment of the wafer W, which may cause a tilt error or a twist error of the Z moving / rotating unit 15. Therefore, the positioning accuracy deteriorates.

  Further, according to the present embodiment, the conductive contact 70 is attached to the wafer alignment camera 19, and the conductive contact 70 moves integrally with the wafer alignment camera 19. For this reason, by adjusting the positional relationship with the wafer alignment camera 19 in advance when the conductive contactor 70 is attached, the probing height can be adjusted even when the length of the probe 25 changes when the probe card 24 is replaced. By moving the wafer alignment camera 19 in the Z direction so that the alignment height is the same, the height of the tip of the conductive contact 70 is always in a fixed positional relationship with the height of the tip of the probe 25. Therefore, even when the probe card 24 is replaced, it is not necessary to adjust the conductive contact 70, and work efficiency can be improved and costs can be reduced.

  Further, according to the present embodiment, the conductive contact 70 is configured to be relatively movable between the retracted position and the contact position with respect to the wafer alignment camera 19, so that the conductive contact 70 is aligned during wafer alignment. By moving to the retracted position, interference with the wafer W or the wafer chuck 16 can be prevented.

  Further, according to this embodiment, even if the position of the chip to be inspected on the wafer W changes, the distance from the position to the position on the stage member 50 with which the conductive contact 70 contacts is always constant. Therefore, regardless of the position of the chip to be inspected on the wafer W, the wafer chuck 16 (support surface 16a), the wiring 64, the stage member 50 (stage surface 50a), the conductive contact 70, and the cable 76 are connected from the chip back electrode. Since the length of the electrical path connected to the tester body 31 is always constant, high-frequency measurement and dynamic measurement can be stably performed without being affected by resistance or impedance in the electrical path. Wafer level inspection can be performed with high accuracy.

  Further, according to the present embodiment, the stage member 50 is separated from the wafer chuck 16 and the stage member 50 is thermally separated from the wafer chuck 16. For this reason, even when the wafer chuck 16 is heated and cooled during the wafer level inspection, the temperature change of the wafer chuck 16 is not easily transferred to the stage member 50, and a heat insulation effect is obtained. Is prevented from thermal deformation. As a result, the contact position of the conductive contact 70 with respect to the stage surface 50a of the stage member 50 (position in the Z direction) does not change, and the conductive contact 70 always has a constant contact pressure and the stage surface 50a of the stage member 50. Can abut. Therefore, it is possible to improve the measurement accuracy and reliability of the wafer level inspection without being affected by the temperature change of the wafer chuck 16.

  Further, according to the present embodiment, since the wafer chuck 16 and the stage member 50 are separated from each other, the conventional wafer chuck 16 can be reused. It is possible to shorten the manufacturing process, reduce design labor, reduce costs, and the like.

  The embodiments of the present invention have been described above. However, the present invention is not limited to the above examples, and various improvements and modifications may be made without departing from the scope of the present invention. . Hereinafter, some modified examples will be described.

[Modification 1]
In the above-described embodiment, the stage member 50 is separated from the wafer chuck 16. However, the stage member 50 may be integrated with the wafer chuck 16.

  For example, in the modification shown in FIG. 10, the stage member 50 is integrated with the wafer chuck 16. Furthermore, in this modification, the stage member 50 is configured to be rotatable about a rotation shaft 54 provided at an end thereof (wafer chuck side end). That is, the stage member 50 is configured to be rotatable about the Y axis (direction perpendicular to the paper surface), and the stage surface 50a is arranged in parallel to the support surface 16a of the wafer chuck 16 (FIG. 10). And a state of being vertically arranged (illustrated by a broken line in FIG. 10).

  As described above, according to the aspect in which the stage member 50 is foldable, the same effect as the above-described embodiment can be obtained, and the stage member 50 is folded when the wafer W is loaded or unloaded or aligned. By moving the wafer chuck 16 in a state (shown by a broken line in FIG. 10), the operable range of the wafer chuck 16 can be expanded. In addition, a larger wafer chuck 16 can be mounted, and a wafer level inspection can be performed on a large-diameter wafer W.

[Modification 2]
In the above-described embodiment, as shown in FIG. 2, the stage surface 50 a of the stage member 50 has the same shape and the same area as the support surface 16 a of the wafer chuck 16, but is conductive at least within the movable range of the wafer chuck 16. As long as the sexual contactor 70 has the stage surface 50a which can always contact, a different shape or area may be sufficient. For example, the stage surface 50a of the stage member 50 may have the same planar shape (circular shape) as the support surface 16a of the wafer chuck 16 and a larger area than the support surface 16a. Further, as shown in FIG. 11, the side surface of the stage member 50 on the wafer chuck 16 side may be formed in a concave shape along the side surface of the wafer chuck 16. In any aspect, the conductive contact 70 has a stage surface 50a that can always be contacted at least within the movable range of the wafer chuck 16, and the same effects as those of the above-described embodiment can be obtained.

[Modification 3]
In the above-described embodiment, the spring pin is used as the conductive contact 70 that can contact the stage surface 50a of the stage member 50. However, the present invention is not limited to this, and for example, a probe card-like contact such as a cantilever type or a vertical needle type. May be used.

[Modification 4]
In the above-described embodiment, the configuration in which the probe card 24 is provided as the probe holding unit has been described. However, the configuration is not limited thereto, and for example, a manipulator type probe head may be provided.

  DESCRIPTION OF SYMBOLS 10 ... Prober, 11 ... Base, 12 ... Moving base, 13 ... Y-axis moving table, 14 ... X-axis moving table, 15 ... Z-axis moving / rotating part, 16 ... Wafer chuck, 16a ... Support surface, 18 ... Probe Position detection camera, 19 ... Alignment camera, 22 ... Head stage, 23 ... Card holder, 24 ... Probe card, 25 ... Probe, 30 ... Tester, 31 ... Tester body, 32 ... Contact ring, 40 ... Camera lifting mechanism, 50 ... Stage member 50a ... Stage surface 52 ... Connecting member 60 ... Control unit 64 ... Wiring 70 ... Conductive contact 72 ... Z table 74 ... Holder 76 ... Cable 78 ... Contact lift mechanism 100 ... Wafer test system

Claims (5)

A wafer chuck for holding a wafer on which a plurality of chips having electrodes on both sides are formed, the wafer chuck having a conductive support surface in contact with a chip back surface electrode formed on the back surface of the wafer;
A moving rotation mechanism for moving and rotating the wafer chuck;
A probe holder having a probe that contacts a chip surface electrode formed on the surface of the wafer and connects the chip surface electrode to a terminal of a tester;
A probe position detection camera for detecting the height of the probe tip of the probe holding portion;
A wafer alignment camera that detects the position of the chip surface electrode of the wafer held by the wafer chuck;
A first elevating mechanism for elevating the wafer alignment camera in the vertical direction;
Based on the detection result of the probe position detection camera, a controller that controls the first elevating mechanism so that the height of the tip of the probe and the focal position of the wafer alignment camera are the same height;
A stage member that is formed parallel to the support surface and has a conductive stage surface electrically connected to the support surface, and that moves integrally with the wafer chuck;
A conductive contact configured to be movable integrally with the wafer alignment camera and electrically connecting the chip back electrode to the tester in contact with the stage surface;
Prober equipped with.   The prober according to claim 1, further comprising a second lifting mechanism that changes a relative height of the conductive contact with respect to the wafer alignment camera.   The prober according to claim 1, wherein the stage member is configured to be separated from the wafer chuck, and the stage surface and the support surface are electrically connected via a wiring member.   The prober according to claim 1, wherein the stage member is configured integrally with the wafer chuck.   5. The stage member according to claim 1, wherein the conductive contact is always in contact with the stage surface when the probe contacts the chip surface electrode within a movable range of the wafer chuck. The prober according to item 1.

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