JP2014179379A - Wafer inspection apparatus and method for maintaining the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wafer inspection apparatus in which each pogo pin in a pogo frame can be easily replaced even when a plurality of test heads are stacked in a multistage.SOLUTION: A wafer inspection apparatus 10 includes a plurality of test heads 16 arranged in a multistage. A pogo frame 17 mounting a number of pogo pins is mounted to a lower part of each of the test heads 16. Cam mechanisms 27 for converting movement in a side direction of the test heads 16 into movement in an upper direction of the test head 16 are arranged on sides of each of the test heads 16. The cam mechanism 27 has a cam base 30 which can be drawn to the side direction, and a cam follower 29 projected from a rail guide 28 supporting a flange 32 of the test head 16. The cam base 30 has an inclined surface 34 rising toward an opposite direction to the drawing direction. The inclined surface 34 supports the cam follower 29.

Description

  The present invention relates to a wafer inspection apparatus and a maintenance method for the apparatus.

  A prober as a wafer inspection apparatus is used to inspect the electrical characteristics of each semiconductor device on a semiconductor wafer (hereinafter simply referred to as “wafer”) on which a large number of semiconductor devices are formed. The prober has a disk-like probe card facing the wafer, and the probe card has contact probes which are a plurality of columnar contact terminals arranged to face each electrode pad and each solder bump in the semiconductor device of the wafer ( For example, see Patent Document 1.)

  In the prober, each contact probe of the probe card comes into contact with an electrode pad or solder bump in the semiconductor device, and an inspection signal is sent from each contact probe to the electric circuit of the semiconductor device connected to each electrode pad or each solder bump. Check the electrical circuit continuity.

  An inspection signal is sent to each contact probe of the probe card from a test head equipped with an inspection circuit. A pogo frame is interposed between the probe card and the test head, and the pogo frame is used to inspect each contact probe and test head. It has a number of pogo pins that make the circuit electrically conductive. Each pogo pin is an ultra-fine needle conductor and is consumed through repeated contact with each contact probe, and therefore needs to be replaced periodically.

  Normally, as shown in FIG. 10, in the prober 100, the test head 101 is configured to be pivotable upward by a hinge mechanism 102 (see, for example, Patent Document 2), so when replacing each pogo pin, By rotating the test head 101 to expose the pogo frame attached to the lower surface of the test head 101, the operator replaces each pogo pin.

  In recent years, in order to improve the inspection efficiency of a wafer, a plurality of test heads each equipped with a probe card and a pogo frame are provided, and a wafer is transferred to one test head by a transfer stage while another wafer is used by another test head. Wafer inspection apparatuses capable of inspecting semiconductor devices have been developed. In this wafer inspection apparatus, a plurality of test heads are arranged in a multi-stage stack from the viewpoint of reducing the footprint.

JP 2012-063227 A JP 2009-60037 A

  However, in the above-described wafer inspection apparatus having a plurality of test heads, another test head is arranged on one test head, so that each pogo pin of the pogo frame mounted on one test head is replaced. It is difficult to rotate the one test head upward, and it is difficult for an operator to replace each pogo pin in the wafer inspection apparatus.

  An object of the present invention is to provide a wafer inspection apparatus and a maintenance method for the apparatus that can easily replace each pogo pin in a pogo frame even when a plurality of test heads are arranged in a multi-stage stack.

  In order to achieve the above object, the wafer inspection apparatus according to claim 1 includes a plurality of test heads, the plurality of test heads are arranged in multiple stages, and a plurality of pogo pins are mounted on the lower part of each of the test heads. In a wafer inspection apparatus to which a pogo frame is mounted, a first moving mechanism that is arranged beside each of the test heads and converts lateral movement with respect to the test head into upward movement with respect to the test head Each of the pogo frames has a second movement mechanism that allows movement in the lateral direction.

  A wafer inspection apparatus according to a second aspect of the present invention is the wafer inspection apparatus according to the first aspect, wherein the first moving mechanism has a cam base that can be pulled out in the lateral direction and a cam follower that protrudes beside the test head. The cam base has an inclined surface that rises in a direction opposite to the direction in which the cam base is pulled out, and the inclined surface supports the cam follower.

  The wafer inspection apparatus according to claim 3 is the wafer inspection apparatus according to claim 2, wherein two cam bases are provided corresponding to one tester head, and each of the cam bases is provided on both sides of the tester head. When the cam bases are arranged and pulled out, the cam bases are connected by a connecting member.

  A wafer inspection apparatus according to a fourth aspect of the present invention is the wafer inspection apparatus according to the second or third aspect, wherein the cam follower includes rollers.

  The wafer inspection apparatus according to claim 5 is the wafer inspection apparatus according to any one of claims 2 to 4, wherein an inclination angle of the inclined surface of the cam base is 10 kgf or less required for pulling out the cam base. It is set so that it becomes.

  In order to achieve the above object, a maintenance method of a wafer inspection apparatus according to claim 6 includes a plurality of test heads, the plurality of test heads are arranged in multiple stages, and a plurality of test heads are provided at a lower portion of each of the test heads. A first moving mechanism which is mounted with a pogo frame on which a pogo pin is mounted and which is arranged beside each of the test heads to convert a lateral movement with respect to the test head into an upward movement with respect to the test head; Each of the pogo frames is a maintenance method of a wafer inspection apparatus having a second moving mechanism that allows movement in the lateral direction, wherein the first moving mechanism is configured to move the lateral movement in the upward direction. A test head separation step for converting the movement to a direction and moving the test head upward by the movement in the upward direction to separate the test head from the pogo frame. Characterized in that it.

  According to the present invention, the first moving mechanism converts the movement in the lateral direction into the movement in the upward direction, and the test head is lifted by the upward movement to separate the test head from the pogo frame. It is possible to expose the pogo frame by pulling it out in the lateral direction without the upward rotation of the test head. As a result, even if a plurality of test heads are arranged in a multi-stage stack, each pogo pin in the pogo frame can be easily replaced. Further, when the pogo frame is pulled out in the lateral direction, each pogo pin of the pogo frame does not rub against the test head, so that the pogo pin can be prevented from being broken.

1 is a perspective view schematically showing a configuration of a wafer inspection apparatus according to an embodiment of the present invention. 2 is a side view showing an arrangement state of a tester head, a pogo frame, and a probe card in each cell of the wafer inspection apparatus of FIG. It is a perspective view for demonstrating the moving mechanism of the test head in FIG. It is a front view for demonstrating the moving mechanism of the test head in FIG. It is a side view for demonstrating the moving mechanism of the test head in FIG. It is process drawing which shows the test head separation | spacing process as a maintenance method of the wafer inspection apparatus which concerns on this Embodiment. It is a figure which shows the inclination-angle of the inclined surface in the cam base of the cam mechanism in FIG. 3 thru | or FIG. It is a figure for demonstrating drawer of the pogo frame in the maintenance method of the wafer inspection apparatus which concerns on this Embodiment. FIG. 6 is a perspective view showing a modified example of the moving mechanism of the test head of FIGS. 3 to 5. It is a perspective view which shows roughly the structure of the prober as a conventional wafer inspection apparatus.

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

  First, the wafer inspection apparatus according to the present embodiment will be described.

  FIG. 1 is a perspective view schematically showing a configuration of a wafer inspection apparatus according to the present embodiment.

  In FIG. 1, a wafer inspection apparatus 10 includes a cell tower 12 in which a plurality of inspection chambers (cells) 11 are arranged in multiple stages, and is arranged adjacent to the cell tower 12 and includes a transfer mechanism (not shown). And a loader 13 for carrying in and out of each cell 11. Each of the cell tower 12 and the loader 13 has a rectangular parallelepiped shape, and the height is, for example, 2.4 m.

  In the wafer inspection apparatus 10, an operator inputs a wafer on the opposite side (hereinafter referred to as “outside”) of the cell tower 12 on the side adjacent to the loader 13 and on the opposite side of the loader 13 on the side adjacent to the cell tower 12. In addition, a space in which maintenance work of each cell 11 can be performed is secured.

  FIG. 2 is a side view showing an arrangement state of the tester head, the pogo frame, and the probe card in each cell.

  In FIG. 2, the cell 11 includes a probe card 15, a test head 16 on which an inspection circuit (not shown) is mounted, and a pogo frame 17 interposed between the probe card 15 and the test head 16. Seal members 18 and 19 are disposed between the probe card 15 and the pogo frame 17 and between the pogo frame 17 and the test head 16, and the space surrounded by the seal members 18 and 19 is decompressed, whereby the probe card 15. The pogo frame 17 is attached to the test head 16 by vacuum suction.

  Further, the wafer W placed on the chuck plate 14 is carried into the cell 11 by the transfer mechanism, and the wafer W rises together with the chuck plate 14 toward the probe card 15. A seal member 25 is disposed on the upper surface of the chuck plate 14, and when the seal member 25 abuts against the pogo frame 17, the space surrounded by the seal member 25 is decompressed, so that the wafer W is brought together with the chuck plate 14. The wafer W and the probe card 15 come into contact with each other, being drawn toward the probe card 15.

  The probe card 15 is disposed so as to protrude downward from the lower surface of the main body 20, a disk-shaped main body 20, a large number of electrodes (not shown) disposed on substantially the entire upper surface of the main body 20. And a contact probe 21 which is a large number of columnar contact terminals. Each electrode is connected to a corresponding contact probe 21. When the wafer W comes into contact with the probe card 15, each contact probe 21 has electrode pads and solder bumps (each of which is formed on the wafer W). (Not shown).

  The pogo frame 17 has a substantially flat plate-like main body 22 and a plurality of pogo block insertion holes 23 formed in the main body 22, and a large number of pogo pins are arranged in each of the pogo block insertion holes 23. The pogo block 24 thus formed is inserted. The pogo block 24 is connected to an inspection circuit included in the test head 16 and contacts a number of electrodes on the upper surface of the main body 20 of the probe card 15 attached to the pogo frame 17, and to each contact probe 21 connected to the electrode. While flowing the inspection signal, the current flowing from the electric circuit of each semiconductor device on the wafer W via each contact probe 21 is flowed toward the inspection circuit.

  Returning to FIG. 1, a maintenance opening 26 having a size corresponding to the test head 16 and the pogo frame 17 is opened outside each cell 11, and the test head 16 and the pogo frame 17 are connected through the maintenance opening 26. Is exposed.

  By the way, in the wafer inspection apparatus 10, since each cell 11 is arranged in multiple stages, there is no space above the test head 16 in one cell 11, and like the prober 100 described in Patent Document 2. It is difficult to expose the pogo frame 17 mounted on the lower surface of the test head 16 by rotating the test head 16 upward.

  Therefore, when replacing each pogo pin, it is conceivable to pull out the pogo frame 17 to expose the pogo frame 17, but each pogo pin contacts the test head 16 and is connected to the inspection circuit. Therefore, when the pogo frame 17 is moved in the lateral direction (the horizontal direction in FIG. 2) with respect to the test head 16, each pogo pin may rub against the test head 16 and break.

  In the present embodiment, correspondingly, a moving mechanism for separating the test head 16 from the pogo frame 17 is provided.

  3 to 5 are views for explaining the moving mechanism of the test head, FIG. 3 is a perspective view, FIG. 4 is a front view (viewed from the outside), and FIG. 5 is a side view. is there. The moving mechanism of the test head 16 shown in FIGS. 3 to 5 is arranged in each cell 11. In FIG. 5, a cam base 30 described later is indicated by a broken line.

  3 to 5, in each cell 11, a cam mechanism 27 (first moving mechanism) is disposed on both sides of the test head 16.

  The cam mechanism 27 has an L-shaped cross section disposed along a side direction (hereinafter, simply referred to as “side direction”) with respect to the test head 16 (the direction of the white arrow in FIG. 3 and the outward direction). Rail guide 28 which is an elongated member, a cam follower 29 which protrudes perpendicularly to the side direction from the side surface of the rail guide 28, for example, made of rollers, and is arranged along the side direction adjacent to the rail guide 28. It has a substantially prismatic cam base 30 and a substantially flat base 31 disposed below the rail guide 28.

  The rail guide 28, the cam base 30 and the base 31 are not fixed to the test head 16, and the test head 16 can move relative to the rail guide 28, the cam base 30 and the base 31. The cam base 30 is configured to be able to be drawn outward along the lateral direction by a guide or the like, while the rail guide 28 is allowed to move only in the vertical direction, and the base 31 is fixed to the cell 11 and is not allowed to move.

  The test head 16 has a flange 32 that protrudes perpendicularly to the lateral direction at the top, and the flange 32 is supported by a rail guide 28. An assist spring 33 is disposed between the rail guide 28 and the base 31 to urge the rail guide 28 upward with respect to the base 31. The cam base 30 has an inclined surface 34 that rises in the direction opposite to the side direction on the upper surface, and the inclined surface 34 supports the cam follower 29.

  Further, the pogo frame 17 has side walls 35 erected upward from both sides of the main body 22, and the side walls 35 have guides 36 (second movement) that allow the pogo frame 17 to move in the lateral direction. Mechanism).

  FIG. 6 is a process diagram showing a test head separation process as a maintenance method of the wafer inspection apparatus according to the present embodiment. In FIGS. 6A and 6B, the cam base 30 is indicated by a broken line.

  In FIG. 6, first, the decompression of the space surrounded by the seal members 18 and 19 is stopped, the mounted state of the pogo frame 17 and the probe card 15 with respect to the test head 16 is released, and the probe card 15 is moved to the cell by the transport mechanism. 11, the operator pulls out the cam base 30 in the lateral direction (the direction of the white arrow in the figure).

  At this time, the cam follower 29 receives a drag force perpendicular to the inclined surface 34 from the inclined surface 34, but the rail guide 28 to which the cam follower 29 is coupled is only allowed to move in the vertical direction. 29 is only raised in the direction of the black arrow in the figure (FIG. 6A).

  As the cam follower 29 rises, the rail guide 28 also rises. However, the rail guide 28 supports the flange 32 of the test head 16, so that the test head 16 is raised via the flange 32.

  At this time, since the assist spring 33 biases the rail guide 28 upward, the assist spring 33 assists the cam follower 29 to be lifted by the inclined surface 34, and as a result, the pulling force required for pulling out the cam base 30 is reduced.

  Thereafter, when the cam base 30 continues to be pulled out in the lateral direction, the cam follower 29 climbs up the inclined surface 34 relatively. However, the cam follower 29 climbs up the inclined surface 34 and is a hollow follower stopper provided on the upper surface of the cam base 30. When reaching 37, the cam follower 29 stops rising, and the test head 16 also does not rise thereafter (FIG. 6B).

  When the cam follower 29 reaches the follower stopper 37, the test head 16 is raised by a predetermined distance and separated from the pogo frame 17 (FIG. 6C) (test head separation step).

  Further, in the cam mechanism 27 of the wafer inspection apparatus 10, the pulling force necessary for pulling out the cam base 30 by the operator is set to 10 kgf or less, for example. Specifically, the assist spring 33 urges the rail guide 28 upward by 45 kgf to 55 kgf, and the inclination angle (θ in FIG. 7) of the inclined surface 34 is 10 ° to 14 °, preferably 10.5. It is set to ° to 11.5 °. In this case, although depending on the biasing force of the assist spring 33 (for example, the pulling force is reduced by about 5 kgf at 50 kgf), the inclined angle of the inclined surface 34 is 10 ° and the pulling distance of the cam base 30 is 85 mm. For example, if the required pulling force is 1 kgf to 6.8 kgf, the inclined angle of the inclined surface 34 is 14 °, and the pulling distance of the cam base 30 is 60 mm, the required pulling force is 1.4 kgf to 9. 5 kgf.

  In the maintenance method of the wafer inspection apparatus according to the present embodiment, after the test head 16 is lifted and separated from the pogo frame 17, the operator pulls the pogo frame 17 sideways as shown in FIG. The guide 36 of the pogo frame 17 is preferably constituted by, for example, an LM guide, whereby the pulling force necessary for pulling out the pogo frame 17 by the operator can be reduced. In FIG. 8, the cam mechanism 27 is omitted.

  According to the wafer inspection apparatus 10 described above, the cam mechanism 27 converts the lateral movement of the cam base 30 into the upward movement, and the test head 16 is lifted by the upward movement to move the test head 16. Since it is separated from the pogo frame 17, the pogo frame 17 can be pulled out to be exposed without accompanying upward rotation of the test head 16. As a result, even when the plurality of cells 11 are arranged in a multi-stage stack and the plurality of test heads 16 are substantially arranged in a multi-stage stack, each pogo pin in the pogo frame 17 can be easily replaced. Further, when the pogo frame 17 is pulled out in the lateral direction, each pogo pin of the pogo frame 17 does not rub against the test head 16, so that the pogo pin can be prevented from being broken.

  In the wafer inspection apparatus 10 described above, the cam follower 29 projecting vertically from the rail guide 28 in the lateral direction on the side of the test head 16 is supported by the inclined surface 34 of the cam base 30, so that when the cam base 30 is pulled out, the inclined surface 34. Raises the cam follower 29 so that the test head 16 can be easily moved upward.

  Further, in the wafer inspection apparatus 10 described above, the cam mechanism 27 is mainly disposed along the lateral direction adjacent to the rail guide 28 along the lateral direction, and is pulled out laterally. Since the cam base 30 and the cam follower 29 supported by the inclined surface 34 of the cam base 30 are configured, the space required for arranging the cam mechanism 27 can be reduced, and the wafer inspection apparatus 10 can be enlarged. Can be prevented.

  Furthermore, in the wafer inspection apparatus 10 described above, since both the test head 16 and the pogo frame 17 are pulled out in the lateral direction, both the test head 16 and the pogo frame 17 can be pulled out of the cell tower 12. Thus, the work efficiency of the worker can be improved.

  In the wafer inspection apparatus 10 described above, since the cam follower 29 is composed of rollers, it is possible to reduce the resistance when the cam follower 29 moves along the inclined surface 34, thereby reducing the pulling force required for pulling out the cam base. Furthermore, since the inclination angle of the inclined surface 34 of the cam base is set so that the pulling force required for pulling out the cam base is 10 kgf or less, the burden on the operator can be reduced.

  As described above, the present invention has been described using the above-described embodiment, but the present invention is not limited to the above-described embodiment.

  For example, as shown in FIG. 9, when the cam base 30 is pulled out, the two cam bases 30 arranged on both sides of the test head 16 may be connected by a connecting member 38. As a result, the cam followers 29 on both sides of the test head 16 can be raised at the same time, so that the test head 16 can be prevented from tilting when moving upward.

W wafer 10 wafer inspection device 15 probe card 16 test head 17 pogo frame 27 cam mechanism 28 rail guide 29 cam follower 30 cam base 33 assist spring 34 inclined surface 36 guide 38 connecting member

Claims (6)

In a wafer inspection apparatus comprising a plurality of test heads, wherein the plurality of test heads are arranged in multiple stages, and a pogo frame on which a large number of pogo pins are mounted on each lower part of the test heads
A first moving mechanism disposed beside each of the test heads to convert a lateral movement with respect to the test head into an upward movement with respect to the test head;
Each of the pogo frames has a second moving mechanism that allows movement in the lateral direction. The first moving mechanism has a cam base that can be pulled out in the lateral direction, and a cam follower that projects beside the test head,
The wafer inspection apparatus according to claim 1, wherein the cam base has an inclined surface that rises in a direction opposite to a direction in which the cam base is pulled out, and the inclined surface supports the cam follower. Two cam bases are provided corresponding to one tester head, and each of the cam bases is disposed on both sides of the tester head,
The wafer inspection apparatus according to claim 2, wherein when the cam bases are pulled out, the cam bases are connected by a connecting member.   4. The wafer inspection apparatus according to claim 2, wherein the cam follower comprises rollers.   5. The wafer inspection apparatus according to claim 2, wherein an inclination angle of the inclined surface of the cam base is set so that a pulling force required for pulling out the cam base is 10 kgf or less. . A plurality of test heads are provided, the plurality of test heads are arranged in multiple stages, and a pogo frame on which a large number of pogo pins are mounted is attached to the lower part of each of the test heads. A first movement mechanism that converts a lateral movement of the test head into an upward movement of the test head, wherein each of the pogo frames allows a second movement of the test head; A maintenance method of a wafer inspection apparatus having a mechanism,
Test head separation in which the first moving mechanism converts the movement in the lateral direction into the movement in the upward direction, and the test head is lifted by the movement in the upward direction to separate the test head from the pogo frame. A maintenance method for a wafer inspection apparatus, comprising a step.

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