JP7174316B2 - load distribution plate - Google Patents

Description

The present invention relates to a prober for inspecting electrical characteristics of a plurality of chips formed on a semiconductor wafer and a load distribution plate for installing the prober on the floor.

A semiconductor manufacturing process includes a large number of processes, and various inspections are performed in various manufacturing processes for quality assurance and yield improvement. For example, a wafer level inspection is performed at the stage where a plurality of chips (also called semiconductor devices) are formed on a semiconductor wafer.

Wafer level inspection is performed using a prober that brings probes into contact with electrode pads of each chip (see Patent Document 1, for example). The probes are electrically connected to the terminals of the test head, supply power and test signals from the test head to each chip through the probes, and detect output signals from each chip to determine whether they operate normally. to measure.

In the semiconductor manufacturing process, in order to reduce the manufacturing cost, the size of the wafer is increased and further miniaturization (integration) is promoted, and the number of chips formed on one wafer is increasing significantly. ing. Along with this, the time required to inspect one wafer with a prober is also increasing, and an improvement in throughput is required. Therefore, in order to improve the throughput, multi-probing is performed in which a large number of probes are provided so that a plurality of chips can be inspected at the same time.

On the other hand, one of the simplest ways to improve the throughput is to increase the number of probers. However, increasing the number of probers raises the problem that the installation area of the probers in the production line also increases. Moreover, increasing the number of probers increases the cost of the device accordingly. Therefore, it is required to improve throughput while suppressing an increase in installation area and an increase in equipment cost.

In order to address such a problem, Patent Document 2 discloses a prober having a plurality of measuring sections stacked in multiple stages. This prober has a laminated structure in which a plurality of measuring sections are laminated in multiple stages. Therefore, since wafer level inspection can be performed for each measurement unit, an increase in installation area and an increase in equipment cost can be suppressed, and throughput can be improved.

JP 2009-60037 A JP 2014-150168 A

By the way, the prober usually has a plurality of supporting legs (for example, level pads) at the bottom of the prober main body (housing). The prober is installed on the floor of a clean room in a semiconductor factory via these supporting legs, and the floor of the clean room often has a grating structure. Grating floors have a lower load capacity than concrete floors.

When a prober enlarged in the height direction as in Patent Document 2 is installed on the floor of such a grating structure, the load of the prober applied from the supporting legs to the floor increases. The permissible load per unit area is set for the floor of the grating structure, but the permissible load may be locally exceeded at the contact portion of the support leg.

In order to avoid such local load application, a metal plate (for example, a 10 mm thick aluminum plate or a 5 mm thick stainless steel plate) having a larger area than the ground contact area of the supporting leg is placed between the supporting leg and the floor. It is conceivable to lay a metal plate such as a plate). By using such a metal plate, the load of the prober applied to the floor of the grating structure is distributed, so there is an advantage that the load applied per unit area of the floor can be reduced.

However, when the weight of the prober becomes considerably large, the thickness of the metal plate must be increased to withstand the load, so the weight of the metal plate cannot be ignored. For example, when it is assumed that a metal plate of 1 m ² is laid, the weight of an aluminum plate with a thickness of 10 mm is 27 kg, and the weight of a stainless steel plate with a thickness of 5 mm is 40 kg. Therefore, even if the load of the prober can be distributed by the metal plate, there is a concern that the total weight of the prober including the metal plate will exceed the allowable load of the floor of the grating structure.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a lightweight load distribution plate capable of effectively distributing the load of the prober and a prober equipped with the load distribution plate. .

In order to achieve the object of the present invention, the load distribution plate of the present invention is a load distribution plate installed between a support leg that supports a prober and a floor surface. It has a honeycomb structure plate having partition walls in which cells are partitioned.

In one form of the load distribution plate of the present invention, the cross-sectional shape of the cells is preferably hexagonal or larger.

In one aspect of the load distribution plate of the present invention, it is preferable that a back plate is provided on the floor surface side surface of the honeycomb structure plate.

In one aspect of the load distribution plate of the present invention, it is preferable that a surface plate is provided on the surface of the honeycomb structure plate opposite to the floor surface.

In order to achieve the object of the present invention, the prober of the present invention is provided with the load dispersing plate of the present invention on the supporting legs for supporting the prober.

One form of the prober of the present invention preferably has a plurality of measuring sections stacked in multiple stages.

According to the present invention, it is possible to provide a lightweight load distribution plate that can effectively distribute the load of the prober, and a prober equipped with the load distribution plate.

1 is an external view showing the overall configuration of a prober according to an embodiment of the present invention; FIG. FIG. 2 is a plan view showing the prober shown in FIG. 1; FIG. 2 is a front view of the measuring unit showing the internal structure of the measuring unit of FIG. 1; FIG. 2 is a side view of the measurement unit showing the internal structure of the measurement unit of FIG. 1; Schematic diagram showing the configuration of the measurement unit Schematic diagram showing the measurement unit ready for inspection The perspective view which showed the structure of the load distribution board Explanatory drawing explaining the load of the prober on the floor when the support legs are installed directly on the floor Explanatory drawing explaining the load of the prober applied to the floor when a metal plate is laid between the supporting legs and the floor. Explanatory drawing explaining the load of the prober applied to the floor when the supporting legs are installed on the floor via the load distribution plate of the embodiment. The perspective view which showed another example of the load distribution board

Preferred embodiments of the present invention will now be described with reference to the accompanying drawings.

FIG. 1 is an external view showing the overall configuration of a prober 10 according to an embodiment of the invention. FIG. 2 is a plan view of the prober 10 shown in FIG.

As shown in FIGS. 1 and 2, the prober 10 of the embodiment is installed on the floor surface of a grating structure floor 100, which is the floor of a clean room, with a load distribution plate 102 interposed therebetween. The load distribution plate 102 shown in FIG. 1 is an example of the load distribution plate of the present invention, and the load distribution plate 102 will be described later.

The prober 10 includes a loader section 14 that supplies and retrieves wafers W (see FIG. 5) to be inspected, and a measurement unit 12 that is arranged adjacent to the loader section 14 and has a plurality of measurement sections 16 . In the measurement unit 12 , when the wafer W is supplied from the loader section 14 to each measurement section 16 , each measurement section 16 inspects the electrical characteristics of each chip of the wafer W (wafer level inspection). Then, the wafer W inspected by each measurement unit 16 is recovered by the loader unit 14 . The loader section 14 and the measurement unit 12 are housed in a housing 30 (see FIGS. 3 and 4). The prober 10 also includes an operation panel 21 and a control device (not shown) for controlling each part.

The loader section 14 has a load port 18 on which the wafer cassette 20 is placed, and a transfer unit 22 that transfers the wafer W between each measurement section 16 of the measurement unit 12 and the wafer cassette 20 . The transport unit 22 includes a transport unit driving mechanism (not shown), and is configured to be movable in the X and Z directions and to be rotatable in the θ direction (around the Z direction). Further, the transport unit 22 has a transport arm 24, and the transport arm 24 can be extended and retracted back and forth by the transport unit driving mechanism. A suction pad (not shown) is provided on the upper surface of the transfer arm 24, and the transfer arm 24 holds the wafer W by vacuum-sucking the rear surface of the wafer W with the suction pad. As a result, the wafer W in the wafer cassette 20 is taken out by the transfer arm 24 of the transfer unit 22 and transferred to each measurement section 16 of the measurement unit 12 while being held on its upper surface. In addition, the inspected wafer W, which has been inspected, is returned from each measuring section 16 to the wafer cassette 20 through the reverse route.

3 and 4 are diagrams showing the internal structure of the measuring unit 12 of FIG. 3 is a view of the measurement unit 12 viewed from the front side (loader section 14 side), and FIG. 4 is a view of the measurement unit 12 viewed from the side.

As shown in FIGS. 3 and 4, the measurement unit 12 has a laminated structure in which a plurality of measurement sections 16 are laminated in multiple stages, and each measurement section 16 is two-dimensional along the X and Z directions. are arranged systematically. In the embodiment, as an example, the measurement unit 12 is shown in which four measurement units 16 are stacked in the X direction in three stages in the Z direction. Therefore, the prober 10 of the embodiment having such a measurement unit 12 has a structure that is enlarged in the height direction.

The measurement unit 12 includes a housing 30 having a grid shape in which a plurality of frames are combined in a grid pattern. That is, the housing 30 is constructed by combining a plurality of frames extending in the X direction, the Y direction, and the Z direction in a grid pattern, and the space surrounded by these frames has a substantially rectangular parallelepiped shape. ing. Components of the measurement unit 16 are arranged in this space.

Further, a plurality of supporting legs 32 for installing the housing 30 on the load distribution plate 102 are provided on the bottom 30A of the housing 30 . The support legs 32 are composed of level pads, and it is possible to easily adjust the horizontal and height directions of the housing 30 with respect to the floor 100 having a grating structure.

FIG. 5 is a schematic diagram showing the configuration of the measuring section 16. As shown in FIG.

As shown in FIG. 5, each measurement unit 16 has the same configuration, and includes a wafer chuck 50 for holding a wafer W, a head stage 52, a test head 54, a probe card 56, a test A pogo frame 58 interposed between the head 54 and the probe card 56 is provided.

The test head 54 is supported above the head stage 52 by a support member (not shown). The test head 54 is electrically connected to the probes 66 of the probe card 56, supplies power and test signals to each chip for electrical inspection, and detects output signals from each chip to operate normally. to measure

The head stage 52 is supported by the frame member 34 forming part of the housing 30 and has a pogo frame mounting portion 53 that is a circular opening corresponding to the planar shape of the pogo frame 58 . The pogo frame mounting portion 53 has positioning pins 63 , and the pogo frame 58 is fixed to the pogo frame mounting portion 53 while being positioned by the positioning pins 63 .

The pogo frame 58 electrically connects the terminals formed on the lower surface of the test head 54 (the surface facing the pogo frame 58) and the terminals formed on the upper surface of the probe card 56 (the surface facing the pogo frame 58). It has a number of pogo pins (not shown) that connect to the Ring-shaped sealing members 60 and 62 are provided on the outer periphery of the upper surface (the surface facing the test head 54) and the lower surface (the surface facing the probe card 56) of the pogo frame 58, respectively. Then, the space surrounded by the test head 54, the pogo frame 58 and the sealing member 60 and the space surrounded by the probe card 56, the pogo frame 58 and the sealing member 62 are decompressed by suction means (not shown), thereby performing the test. The head 54, pogo frame 58 and probe card 56 are integrated.

The probe card 56 has a large number of probes 66 corresponding to the electrodes of each chip of the wafer W. As shown in FIG. Each probe 66 is formed to protrude downward from the lower surface of the probe card 56 (the surface facing the wafer chuck 50), and each terminal provided on the upper surface of the probe card 56 (the surface facing the pogo frame 58). is electrically connected to Therefore, when the test head 54 , the pogo frame 58 and the probe card 56 are integrated, each probe 66 is electrically connected to each terminal of the test head 54 via each pogo pin of the pogo frame 58 . The probe card 56 of this example has a large number of probes 66 corresponding to the electrodes of all the chips of the wafer W to be inspected. inspection is carried out.

The wafer chuck 50 holds the wafer W by vacuum suction, for example. The wafer chuck 50 is detachably supported by the alignment device 70 and is movable in the X, Y, Z, and θ directions by the alignment device 70 . A ring-shaped sealing member 64 is provided on the outer peripheral portion of the upper surface (wafer mounting surface) of the wafer chuck 50 . Then, the space surrounded by the probe card 56 , the wafer chuck 50 and the seal member 64 is depressurized by suction means (not shown), thereby drawing the wafer chuck 50 toward the probe card 56 . As a result, as shown in FIG. 6, the probes 66 of the probe card 56 come into contact with the electrode pads of the chips of the wafer W so that the inspection can be started.

As described above, the prober 10 of the embodiment has the measurement unit 12 (see FIGS. 3 and 4) having a laminated structure in which a plurality of measurement units 16 are laminated in multiple stages. It has a large-sized structure. Therefore, when the prober 10 is directly installed on the floor 100 having a grating structure (see FIG. 1), the permissible load of the floor 100 may be locally exceeded at the grounding portions of the support legs 32 . Therefore, in the prober 10 of the embodiment, the load distribution plate 102 is laid in the installation area of the prober 10 on the floor 100 , and the support legs 32 are grounded and fixed to the load distribution plate 102 , so that the prober applied to the floor 100 is It distributes 10 loads. In other words, the prober 10 according to the embodiment is provided with the load distribution plate 102 on each support leg 32 , and can be installed on the floor 100 via the load distribution plate 102 .

FIG. 7 is a perspective view showing the structure of the load distribution plate 102. As shown in FIG. The load distribution plate 102 is composed of a honeycomb structure plate 106, a front plate 104A arranged on one surface of the honeycomb structure plate 106, and a back plate 104B arranged on the other surface of the honeycomb structure plate 106. That is, the load distribution plate 102 has a laminated structure (sandwich structure) in which the honeycomb structure plate 106 is sandwiched between the top plate 104A and the back plate 104B.

As the honeycomb structure plate 106, the front plate 104A and the back plate 104B, metal plates such as aluminum and stainless steel can be used. Moreover, the honeycomb structure plate 106, the front plate 104A and the back plate 104B may be made of the same material, or may be made of different materials. Note that the top plate 104A and the back plate 104B may be made of a material other than a metal plate (for example, a resin material) as long as a predetermined mechanical strength (for example, rigidity such as bending rigidity) can be secured. .

The honeycomb structure plate 106 is provided with partition walls (ribs) 106B in which a plurality of cells 106A are partitioned. Each cell 106A is configured by a hole penetrating both surfaces of the honeycomb structure plate 106. As shown in FIG. Moreover, the cross-sectional shape of each cell 106A is hexagonal. The cross-sectional shape of each cell 106A is preferably triangular or more polygonal, particularly a hexagonal polygon. Thereby, the honeycomb structure plate 106 can have a predetermined load distribution function.

According to the load distribution plate 102 having such a laminated structure, it is possible to reduce the weight of the load distribution plate 102 while ensuring a predetermined bending rigidity, as compared with, for example, a plate composed only of metal plates. The prober 10 can be stably installed on the floor 100 without exceeding the allowable load of the floor 100 .

In the embodiment, the load distribution plate 102 has a configuration in which the front plate 104A and the back plate 104B are arranged on both sides of the honeycomb structure plate 106 as an example of a preferable aspect, but the configuration is not limited to this. For example, the load distribution plate 102 may consist of only the honeycomb structure plate 106 . Alternatively, the honeycomb structure plate 106 may have a configuration in which the top plate 104A or the back plate 104B is arranged on one of the surfaces. Even with the load distribution plate 102 of such a modified example, the weight can be reduced, and the prober 10 can be stably installed on the floor 100 without exceeding the allowable load of the floor 100 .

Here, the load between the load distribution plate 102 of the embodiment and a load distribution plate composed of only a metal plate, for example, will be compared. For example, when the load distribution plate 102 of the embodiment is configured to have the same flexural rigidity with respect to a conventional aluminum plate and a stainless steel plate, the load distribution plate 102 of the embodiment is 1/7 the weight of the aluminum plate. It can be constructed with a weight that is 1/11 that of a stainless steel plate.

Therefore, according to the load distribution plate 102 of the embodiment, weight reduction can be achieved while ensuring the bending rigidity of a conventional metal plate. Further, according to the prober 10 of the embodiment, since the support leg portion 32 of the prober 10 is provided with the load distribution plate 102 having the honeycomb structure plate 106, the load of the prober 10 applied from the prober 10 to the floor 100 is effectively distributed. The prober 10 can be provided with a load distribution plate 102 that is evenly distributed and lightweight.

The following effects can also be expected by using the load distribution plate 102 of the embodiment.

That is, on the basis of bending rigidity, the thickness of the load distribution plate 102 can be significantly thinner than the thicknesses of the aluminum plate and the stainless steel plate. For this reason, the use of the load distribution plate 102 of the embodiment is advantageous for dimensional restrictions in the height direction of the prober 10 . Further, by providing the prober 10 with the thin load distribution plate 102, the center of gravity of the entire apparatus is lowered, which is advantageous in terms of vibration of the entire apparatus including the load distribution plate 102. FIG.

On the other hand, if the thickness of the load distribution plate 102 is made thicker than the thickness based on the above bending rigidity, the load distribution plate 102 of the embodiment obtains much higher bending rigidity than the aluminum plate and the stainless steel plate. be able to.

The load of the prober 10 applied to the floor 100 will be described below with reference to the drawings.

The schematic diagram shown in FIG. 8 explains the load of the prober 10 applied to the floor 100 when the support leg 32 of the prober 10 is directly installed on the floor 100 . Also, in FIG. 8, the magnitude of the load is indicated by an arrow. A line C indicated by a two-dot chain line in FIG. 8 indicates the allowable load of the floor 100. When the magnitude of the load indicated by the arrow in FIG. When the magnitude of the load indicated by the arrow is below the line C, it indicates that the load exceeds the allowable load. The same applies to FIGS. 9 and 10 described below.

As shown in FIG. 8, the load of the prober 10 is concentrated on the contact portion of the floor 100 where the support leg 32 is in contact with the ground, and an excess allowable load portion A exceeding the allowable load of the floor 100 is generated at the contact portion. There's a problem.

The schematic diagram shown in FIG. 9 illustrates the load of the prober 10 applied to the floor 100 when a metal plate 110 such as an aluminum plate or a stainless steel plate is laid between the support legs 32 and the floor 100 . By using such a metal plate 110, the load of the prober 10 applied to the floor 100 is dispersed, so that the load applied per unit area of the floor 100 can be reduced. A line D indicated by a chain double-dashed line in FIG. 9 indicates the load of the metal plate 110 applied to the floor 100 .

However, when the weight of the prober 10 becomes considerably large, the thickness of the metal plate 110 must be increased so as to withstand the load, and the weight also increases. Therefore, even if the load of the prober 10 can be distributed by the metal plate 110, the total weight of the prober 10 including the metal plate 110 causes the excessive load portion A at the contact portion of the support leg 32. be.

The schematic diagram shown in FIG. 10 explains the load of the prober 10 applied to the floor 100 when the support legs 32 of the prober 10 are installed on the floor 100 via the load distribution plate 102 of the embodiment. A line E indicated by a chain double-dashed line in FIG. 10 indicates the load of the load distribution plate 102 applied to the floor 100 .

As shown in FIG. 10, by providing the prober 10 with a load distribution plate 102 having a honeycomb structure plate 106 (see FIG. 7), the load of the prober 10 applied from the prober 10 to the floor 100 can be effectively distributed. . Moreover, since the load distribution plate 102 is thin and lightweight, it is possible to solve the problem that the allowable load excess portion A occurs at the contact portion of the support leg portion 32 .

As described above, according to the prober 10 of the embodiment, since it is equipped with the weight-reduced load distribution plate 102, there is a problem specific to the structure that is enlarged in the height direction, in other words, the floor 100 of the grating structure. The problem of exceeding the allowable load can be eliminated. Further, the configuration in which the prober 10 is installed on the floor 100 via one load distribution plate 102 is not limited, and the prober 10 may be installed on the floor 100 via a plurality of load distribution plates 102 . For example, a load distribution plate 102 may be provided for each of one or more support legs 32 .

FIG. 11 is a perspective view showing another example of the load distribution plate 102. FIG. The load distribution plate 102 in FIG. 11 is configured by laying a plurality of (six in FIG. 11) load distribution plates 102A, 102B, 102C, 102D, 102E, and 102F without gaps.

The load distribution plates 102A to 102F do not have the honeycomb structure plate 106 (see FIG. 7) arranged over the entire area, and are arranged in an H-shaped or cross-shaped area indicated by area B. As shown in FIG. In the region B, an earthquake-resistant fixing metal fitting 112 is fixed, and in regions other than the region B, a plurality of slit-shaped holes 114 are formed. The support legs 32 are fixed to the earthquake-resistant fixtures 112, and fixtures for fixing the load distribution plates 102A to 102F to the floor 100 of the grating structure are inserted into the holes 114. FIG.

In other words, the load distribution plates 102A to 102F shown in FIG. 11 only need to have the honeycomb structure plate 106 in the necessary region B (for example, the region including the fixing position of the earthquake-resistant fixing bracket 112) of the entire region. showing. Here, in order to increase the load distribution capability of the load distribution plates 102A to 102F, it is preferable to provide the honeycomb structure plate 106 over the entire area of the load distribution plates 102A to 102F. However, since the load distribution plates 102A to 102F are substantially fixed to the floor 100 and used, the load distribution plates 102A to 102F must be provided with holes 114 for inserting the above-described fixing metal fittings. If the honeycomb structure plate 106 is arranged in the area where the holes 114 are formed among the load distribution plates 102A to 102F, the fixing metal fittings inserted through the holes 114 interfere with the honeycomb structure plate 106, which is not preferable.

Therefore, in the load distribution plates 102A to 102F of the embodiment, the honeycomb structure plate 106 is not arranged in the hole 114 forming region, thereby simplifying the insertion of the fixing bracket, while only the region B excluding the hole 114 forming region has a honeycomb structure. Structural plates 106 are arranged to provide load distribution capability. Since the top plate 104A (see FIG. 7) and the back plate 104B are present in the region where the holes 114 are formed, the load distribution capability of the load distribution plates 102A to 102F as a whole is sufficiently maintained.

Further, as shown in FIG. 11, if the load distribution plate 102 is composed of a plurality of load distribution plates 102A to 102F, the load distribution plates 102A to 102F can be handled more easily than a single large load distribution plate 102. Become. As a result, workability of the load distribution plates 102A to 102F on the floor 100 is improved. Further, from among the plurality of load distribution plates 102A to 102F, the number of load distribution plates 102A to 102F corresponding to the size of the prober 10 (the surface area of the bottom portion 30A) may be selected. It also has the advantage of improving versatility.

Although the prober of the present invention has been described above, the present invention is not limited to the above examples, and various improvements and modifications may be made without departing from the gist of the present invention. For example, the load distribution plate of the present invention is not limited to the prober 10 having a plurality of measuring sections 16 stacked in multiple stages, and can be provided in a prober having a single measuring section.

DESCRIPTION OF SYMBOLS 10... Prober, 12... Measurement unit, 14... Loader part, 16... Measurement part, 18... Load port, 20... Wafer cassette, 21... Operation panel, 22... Transfer unit, 24... Transfer arm, 30... Case, 50 ... wafer chuck, 52 ... head stage, 54 ... test head, 56 ... probe card, 58 ... pogo frame, 60 ... sealing member, 62 ... sealing member, 64 ... sealing member, 66 ... probe, 100 ... floor of grating structure, DESCRIPTION OF SYMBOLS 102... Load distribution board 102A, 102B, 102C, 102D, 102E, 102F... Load distribution board 104... Surface member 106... Honeycomb structure board 110... Metal plate 112... Earthquake-resistant fixing metal fitting 114... Hole

Claims (5)

A load distribution plate provided on a support leg that supports a prober and installed between the support leg and a floor surface,
The load distribution plate has a honeycomb structure plate having partition walls in which a plurality of cells are partitioned,
The load distribution plate has metal fittings to which the support legs are fixed,
The honeycomb structure plate is provided in a part of the load distribution plate including the fixing position where the metal fitting is fixed, and the load distribution plate is provided in the other region excluding the part of the floor surface. A hole is formed for fixing to the
Load distribution plate. The cross-sectional shape of the cell is hexagonal or larger,
The load distribution plate according to claim 1. The load distribution plate is provided with a back plate on the floor surface side surface of the honeycomb structure plate.
The load distribution plate according to claim 1 or 2. The load distribution plate is provided with a top plate on the surface of the honeycomb structure plate opposite to the floor surface.
The load distribution plate according to claim 1 or 2. The floor surface is a grating structure,
The load distribution plate according to any one of claims 1 to 4.

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