JP6736372B2 - Processing equipment - Google Patents

Description

The present invention relates to a processing device that processes a workpiece.

As a processing device, a grinding device that grinds and thins a wafer as a workpiece and a polishing device that grinds a wafer after grinding are known (for example, refer to Patent Document 1). As a grinding device, there is known a device which positions a wafer on a holding table at a carrying position and a grinding position by a turntable having a pair of holding tables on its upper surface. The grinding device grinds the wafer while supplying the grinding water between the wafer and the grinding wheel during the grinding process, and the waste liquid containing the processing waste is discharged through the water case around the turntable. The polishing apparatus polishes the wafer by CMP (Chemical Mechanical Polishing) while fixing the slurry to the polishing pad, and the waste liquid of the slurry is discharged through the water case around the turntable.

JP, 2014-50932, A

However, since the grinding water in the water case contains processing chips and the slurry contains loose abrasive grains, these processing chips and slurry stay on the bottom plate of the water case. If the processing waste or slurry is left on the bottom plate, it may become solid around the turntable, and the turntable may not be able to rotate. In addition, it is necessary to stop the apparatus frequently in order to clean the solidified processing waste and slurry, and there is a problem that the wafer cannot be processed continuously.

The present invention has been made in view of the above points, and an object of the present invention is to provide a processing device capable of continuously processing a workpiece by preventing the processing waste from solidifying in the device. One

A processing apparatus according to one aspect of the present invention includes a turntable that can rotate about its center, a holding table that holds a workpiece by arranging it at an equal angle around the center of the turntable, and a holding table Processing means for processing the processed work piece, and a processing waste liquid containing processing waste that has an opening for exposing the turntable and accommodates the turntable and flows down from the turntable. A water case that drains from the mouth, and the bottom plate of the water case has an inclined surface that is inclined lower than the opposite side of the drain port with the drain port side sandwiching the center of the turntable. A side face is provided with a brush whose bristles are directed to the bottom plate of the water case, and the brush is rotated on the inclined surface by the rotation of the turntable, and the processing waste accumulated on the inclined surface of the water case is removed. The agitation processing waste liquid is flowed down the inclined surface and drained from the drainage port .

According to this structure, the bottom plate of the water case is stirred by the brush provided on the side surface of the turntable each time the turntable rotates. Since the processing waste is swept out around the water case, the processing waste does not stay on the outer periphery of the turntable and solidify, and the rotation of the turntable is not hindered. Further, the frequency of cleaning the processing scraps around the turntable can be reduced, and the workpiece can be continuously processed.

According to the present invention, it is possible to prevent the processing waste from solidifying in the apparatus and continuously process the workpiece.

It is a perspective view of a CMP polishing apparatus according to the present embodiment. It is a figure which shows the state which the slurry solidified on the outer periphery of the water case which concerns on a comparative example. It is a figure for demonstrating the attachment position to the turntable of the brush which concerns on this Embodiment. It is a figure which shows the positional relationship between the brush and the bottom plate in FIG. It is a figure for demonstrating the sweeping out of the slurry in the brush which concerns on this Embodiment. It is a figure which shows an example of the sweeping-out operation of the brush which concerns on this Embodiment. It is a figure which shows an example of the sweeping-out operation of the brush which concerns on this Embodiment. It is a figure which shows an example of the sweeping-out operation of the brush which concerns on this Embodiment. It is a figure which shows an example of the sweeping-out operation of the brush which concerns on this Embodiment. It is a figure which shows an example of the sweeping-out operation of the brush which concerns on this Embodiment.

The CMP polishing apparatus according to the present embodiment will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view of a CMP polishing apparatus according to this embodiment. FIG. 2 is a diagram showing a state where the slurry is solidified on the outer circumference of the water case according to the comparative example. The CMP polishing apparatus according to the present embodiment is not limited to the apparatus configuration dedicated to polishing processing as shown in FIG. 1, and for example, a series of processing such as grinding processing, polishing processing, and cleaning processing can be performed automatically. It may be incorporated in a fully automatic type processing device. Further, in the present embodiment, a CMP polishing device is exemplified as the processing device, but the processing device may be any device provided with a brush on the side surface of the turntable, and may be, for example, a grinding device.

As shown in FIG. 1, the CMP polishing apparatus 1 is a fully automatic type processing apparatus and performs a series of operations including a loading process, a polishing process, a cleaning process, and an unloading process on a wafer W as a workpiece. It is configured to be performed automatically. The wafer W is formed into a substantially disc shape, and is loaded into the CMP polishing apparatus 1 while being housed in the cassette C. The wafer W may be a semiconductor wafer in which semiconductor devices such as IC and LSI are formed on a semiconductor substrate, or an optical device wafer in which optical devices such as LEDs are formed on an inorganic material substrate. Further, the wafer W may be a semiconductor substrate or an inorganic material substrate after device formation.

On the front side of the base 11 of the CMP polishing apparatus 1, a pair of cassettes C containing a plurality of wafers W are placed. Behind the pair of cassettes C, a cassette robot 16 for loading/unloading the wafer W to/from the cassette C is provided. A positioning mechanism 21 for positioning the unprocessed wafer W and a cleaning mechanism 26 for cleaning the processed wafer W are provided diagonally behind the cassette robot 16. Between the positioning mechanism 21 and the cleaning mechanism 26, a carry-in means 31 for carrying the unprocessed wafer W into the holding table 41 and a carry-out means 36 for carrying out the processed wafer W from the holding table 41 are provided. ..

The cassette robot 16 is configured by providing a hand portion 18 at the tip of a robot arm 17 formed of a multi-joint link. In the cassette robot 16, the unprocessed wafer W is transferred from the cassette C to the positioning mechanism 21, and the processed wafer W is transferred from the cleaning mechanism 26 to the cassette C.

The positioning mechanism 21 is configured by arranging a plurality of positioning pins 23 around the temporary storage table 22 that can move forward and backward with respect to the center of the temporary storage table 22. In the positioning mechanism 21, the center of the wafer W is positioned at the center of the temporary table 22 by abutting the plurality of positioning pins 23 on the outer peripheral edge of the wafer W placed on the temporary table 22.

In the carry-in means 31, the wafer W is lifted from the temporary storage table 22 by the carry-in pad 33 and the carry-in pad 33 is swung by the carry-in arm 32, so that the wafer W is carried into the holding table 41. In the carry-out means 36, the carry-out pad 38 lifts the wafer W from the holding table 41, and the carry-out arm 37 pivots the carry-out pad 38 to carry the wafer W out of the holding table 41.

The cleaning mechanism 26 is configured by providing various nozzles (not shown) that spray cleaning water and dry air toward the spinner table 27. In the cleaning mechanism 26, the spinner table 27 holding the wafer W is lowered into the base 11, the cleaning water is sprayed in the base 11 to spin the wafer W, and then the dry air is blown to blow the wafer W. Are dried.

Behind the carry-in means 31 and the carry-out means 36, there is provided a water case 46 for receiving a processing waste liquid containing slurry and processing waste flowing down from the turntable 40. The water case 46 is provided by forming an opening in the base 11, and the turntable 40 is accommodated in the water case 46. The carry-in means 31 and the carry-out means 36 side of the water case 46 is a carrying area (see FIG. 3) where the wafer W is carried, and the working area 51 side, which will be described later, is a working area where the wafer W is polished (see FIG. 3)). The upper surface of the turntable 40 is partitioned by a partition plate 45 installed so as to divide the turntable 40 into two between a pair of holding tables 41. The processing area is covered with a case cover 76 (see FIG. 3) to form a processing chamber 76a (not shown in FIG. 1, see FIG. 3), and the transfer area is exposed to the outside from the case cover 76.

The bottom plate 47 of the water case 46 is inclined so that the processing area side becomes lower, and a drain port 48 for draining the processing waste liquid is formed on the processing area side. In the processing area, the drainage port 48 is formed at the lowest position, and the processing waste liquid is smoothly drained from the drainage port 48.

On the bottom plate 47 of the water case 46, there is arranged a turntable 40 having a pair of holding tables 41 arranged at equal intervals in the circumferential direction. Rotating means 49 (see FIG. 3) for rotating the turntable 40 is provided below the turntable 40, and the turntable 40 is rotatable about its center. Each time the turntable 40 makes a half rotation, the wafer W held by the holding table 41 is alternately positioned in the transfer area and the processing area.

The holding table 41 is arranged on the turntable 40 at an equal angle around the center of the turntable 40. Below each holding table 41, a rotating means (not shown) for rotating the holding table is provided. A holding surface 42 for holding the lower surface of the wafer W is formed on the upper surface of each holding table 41. An annular peripheral wall 43 is formed around the holding table 41, and an ejection port 44 connected to an air supply source (not shown) is formed inside the peripheral wall 43 next to the holding table 41. Inside the peripheral wall 43, the slurry that has flown down from the holding table 41 during the polishing process is collected and air is jetted from the jet port 44, so that the slurry is supplied to the polishing pad 53 and reused. Further, the ejection port 44 communicates with the water case 46 through the flow path in the turntable 40, and when the polishing of the wafer W is completed, the slurry accumulated in the peripheral wall 43 passes through the ejection port 44 and is discharged to the water case 46. To be done.

A column 12 is provided upright on the rear side of the water case 46. The column 12 is provided with a machining feed means 61 for feeding the machining means 51 in the Z-axis direction. The processing feed means 61 has a pair of guide rails 62 arranged in front of the column 12 and parallel to the Z-axis direction, and a motor-driven Z-axis table 63 slidably installed on the pair of guide rails 62. ing.

The processing means 51 is supported on the front surface of the Z-axis table 63 via a housing 64. A nut portion (not shown) is formed on the back side of the Z-axis table 63, and a ball screw (not shown) is screwed into the nut portion, and the drive motor 66 is connected to one end of the ball screw (not shown). ing. A ball screw (not shown) is rotationally driven by the drive motor 66, and the processing means 51 is moved along the guide rail 62 in the Z-axis direction.

The processing means 51 is attached to the front surface of the Z-axis table 63 via a housing 64, and has a polishing pad 53 provided below the spindle 54. The processing means 51 polishes the wafer W held by the holding table 41. The spindle 54 is provided with a flange 55, and the processing means 51 is supported by the housing 64 via the flange 55. A platen 52 to which a polishing pad 53 is attached is attached to the lower part of the spindle 54. A large number of holes for fixing the slurry S are formed on the polishing surface of the polishing pad 53.

A slurry supply source 59 that supplies the slurry S between the upper surface of the wafer W and the polishing surface of the polishing pad 53 is connected to the upper portion of the spindle 54. By supplying the slurry S from the slurry supply source 59, the slurry S is fixed on the polishing surface through the flow path in the spindle 54. The slurry S is an alkaline aqueous solution or an acidic aqueous solution containing abrasive grains, and contains, for example, abrasive grains of green carborundum, diamond, alumina, cerium oxide, and CBN (cubic boron nitride).

The CMP polishing apparatus 1 is provided with a control unit (not shown) that integrally controls each unit of the device. The control unit includes a processor that executes various processes, a memory, and the like. The memory is configured by one or a plurality of storage media such as a ROM (Read Only Memory) and a RAM (Random Access Memory) according to the application. In such a CMP polishing apparatus 1, the wafer W is conveyed from the cassette C to the positioning mechanism 21, and the wafer W is centered by the positioning mechanism 21. Next, the wafer W is loaded onto the holding table 41, and the turntable 40 rotates to position the wafer W held on the holding table 41 at the CMP polishing position. At the CMP polishing position 1, the wafer W is polished. Then, the cleaning mechanism 26 cleans the wafer W, and the wafer W is unloaded from the cleaning mechanism 26 to the cassette C.

By the way, in the general CMP polishing apparatus 90 shown in the comparative example of FIG. 2, when the wafer W is processed as described above, the slurry S used for polishing and the processing waste generated by the polishing process are generated around the holding table 101. It is stored inside the peripheral wall 103 provided in the. The slurry S stored in the peripheral wall 103 of the wafer W flows down from the ejection port 104 communicating with the water case 106 to the bottom plate 107 in the processing area of the water case 106 after polishing is completed. Then, the slurry S is discharged from the drain port 108 provided in the bottom plate 107.

A part of the processing waste and the slurry S on the bottom plate 107 is not drained from the drain port 108 but is rotated along with the turntable 100. Since the processing area 106 is covered with the case cover 116 and has high humidity, the slurry S is prevented from being dried and the slurry S is hard to be solidified on the bottom plate 107. However, since the transfer area is exposed to the outside from the case cover 116 and is in a low humidity state, the slurry S carried to the transfer area by the turntable 100 is dried and the outer periphery of the turntable 100 is dried. It is easily solidified. In order to prevent the rotation of the turntable 100 from being stopped due to the solidification of the slurry S, the water case 106 needs to be frequently cleaned, and the CMP polishing apparatus 90 cannot be continuously operated, which lowers the productivity. There is a problem that ends up. Therefore, in the present embodiment, a brush is provided on the side surface of the turntable to sweep out the solidified slurry S on the outer circumference of the turntable.

Hereinafter, the configuration of the brush in the turntable according to the present embodiment will be described with reference to FIGS. 3 to 5. 3 is a diagram for explaining a mounting position of the brush according to the present embodiment on the turntable, FIG. 4 is a diagram showing a positional relationship between the brush and the bottom plate in FIG. 3, and FIG. FIG. 6 is a diagram for explaining the sweeping out of the slurry in the brush according to the present embodiment.

As shown in FIG. 3, on the side surface of the turntable 40 according to the present embodiment, a brush 70 having a large number of bristles 72 provided on the lower surface of a brush base 71 is provided. The brush 70 is provided on the side surface of the turntable 40 in the extension direction of the partition plate 45, and is arranged with the tips of the brush bristles 72 facing the bottom plate 47 of the water case 46. Along with the rotation of the turntable 40, the brush 70 intermittently rotates between the processing area and the transfer area to stir the bottom plate 47 of the water case 46. The processing means 51 is omitted in FIG.

As shown in FIG. 4, when the turntable 40 positions the brush at the stop position at the boundary between the transport area and the processing area, the length a of the brush bristles 72 is substantially equal to the distance b between the brush base 70 and the bottom plate 47. Become. Therefore, at the stop position of the turntable 40, the bristle tips of the brush bristles 72 are in contact with the bottom plate 47 of the water case 46.

When the brush 70 is moved to the transport area by the turntable 40, the distance b between the brush base 71 and the bottom plate 47 is reduced due to the inclination of the bottom plate 47. At this time, the length b of the brush bristles 72 becomes larger than the distance b, so that the bristles 72 are pressed against the bottom plate 47. Therefore, when the brush 70 rotates with the rotation of the turntable 40 in the transfer area, the brush 70 stirs the slurry S solidified by the bottom plate 47 of the water case 46, and the slurry S is swept out to the processing area side.

When the brush is moved to the processing area by the turntable 40, the distance b between the brush base 71 and the bottom plate 47 is increased due to the inclination of the bottom plate 47. At this time, since the length a of the brush bristles 72 is smaller than the distance b, the brush bristles 72 do not reach the bottom plate 47. Therefore, in the processing area, even if the turntable 40 rotates, the bottom plate 47 is not swirled, and the slurry in the processing area is not guided to the transfer area.

As shown in FIG. 5, in the transport area exposed to the outside of the case cover 76 and easily dried, the brush 70 provided on the side surface of the turntable 40 surrounds the turntable 40 each time the turntable 40 rotates. Stir the bottom plate 47 of. The slurry S staying in the transport area is swept from the transport area to the processing area by the brush 70. As a result, the slurry S is prevented from solidifying on the outer periphery of the turntable 40 and the rotation of the turntable 40 is not hindered, so that the wafer W can be continuously processed. Moreover, since the brush bristles 72 do not bend at the stop position, it is possible to prevent the brush bristles 72 from having a habit.

Next, the sweeping operation when the brush 70 stirs the bottom plate 47 of the water case 46 will be described in detail. FIG. 6 is a diagram showing an example of the sweeping operation of the brush according to the present embodiment. For convenience of explanation, the peripheral wall 43 is omitted.

FIG. 6A shows the position of the brush 70 in the stop position. The pair of holding tables 41 are respectively positioned in the processing area and the transfer area, and the wafer W is held on the upper surface of each holding table 41. The partition plate 45 provided between the pair of holding tables 41 of the turntable 40 partitions the processing area and the transfer area, and the brush 70 provided on the side of the partition plate 45 defines the boundary between the processing area and the transfer area. It is located in. At this time, the brush bristles 72 are in contact with the bottom plate 47 of the water case 46 at their tips. With the turntable 40 stopped at this stop position, the wafer W is polished while the slurry S is being supplied, and the slurry S after polishing is discharged to the bottom plate 47 through the ejection port 44 (see FIG. 3).

FIG. 6B shows the position of the brush 70 with the turntable 40 rotated 45° from the stop position. As the turntable 40 rotates, the brush 70 moves to the transfer area exposed to the outside of the case cover 76. At this time, the brush bristles 72 are pressed against the bottom plate 47 in the transport area. As a result, the brush 70 stirs the bottom plate 47 in the transfer area, and the slurry S solidified on the bottom plate 47 is swept out as the turntable 40 rotates. By agitating the periphery of the turntable 40 with the brush 70 in the transport area where the slurry S is easily dried, it is possible to prevent the slurry S from solidifying on the outer periphery of the turntable 40.

FIG. 6C shows the position of the brush 70 with the turntable 40 rotated 90° from the stop position. With the rotation of the turntable 40, the brush 70 moves to the position of the transport area where the distance between the brush base 71 and the bottom plate 47 is shorter than the stop position. At this time, the brush bristles 72 are strongly pressed against the bottom plate 47, and the bottom plate 47 is agitated to sweep out the slurry S.

FIG. 6D shows the position of the brush 70 with the turntable 40 rotated 180° from the stop position. With the rotation of the turntable 40, the brush 70 is positioned at the stop position at the boundary between the processing area and the transfer area. As described above, the wafer W is polished while the slurry S is being supplied at the stop position.

FIG. 6E shows the position of the brush 70 with the turntable 40 rotated 270° from the stop position. As the turntable 40 rotates, the brush 70 moves to the processing area covered by the case cover 76. At this time, the brush bristles 72 do not reach the bottom plate 47 in the processing area. As a result, even if the turntable 40 rotates in the processing area, the brush 70 does not stir the bottom plate 47, so that the slurry S in the processing area is not rotated by the brush 70 to the transfer area.

As described above, in the CMP polishing apparatus 1 as the processing apparatus according to the present embodiment, the bottom plate 47 of the water case 46 is stirred by the brush 70 provided on the side surface of the turntable 40 each time the turntable 40 rotates. Be done. Since the processing waste is swept out around the water case 46, the processing waste does not stay on the outer periphery of the turntable 40 and solidify, and the rotation of the turntable 40 is not hindered. Further, the frequency of cleaning the processing scraps around the turntable 40 can be reduced, and the wafer W as the workpiece can be continuously processed.

In the above embodiment, one brush 70 is provided in the extension direction of one end of the partition plate 45 on the side surface of the turntable 40. However, if the brush 70 can stir the bottom plate 47 in the transfer area, the turntable 40 can be rotated. It may be provided at any position on the side surface of the.

In the above-described embodiment, one drain port 48 is provided, but two or more drain ports 48 may be provided.

In the above embodiment, the turntable 40 is formed in a circular shape, but it may be formed in a polygonal shape.

In the present embodiment, the brush 70 is used to sweep out the slurry S, but the configuration is not particularly limited as long as the slurry S can be swept out.

Further, although the respective embodiments of the present invention have been described, other embodiments of the present invention may be a combination of the above respective embodiments wholly or partially.

The embodiments of the present invention are not limited to the above-described embodiments, and may be variously changed, replaced, or modified without departing from the spirit of the technical idea of the present invention. Furthermore, if the technical idea of the present invention can be realized in another way by the advancement of the technology or another derivative technology, the method may be implemented. Therefore, the claims cover all embodiments that may be included in the scope of the technical idea of the present invention.

In the present embodiment, the configuration in which the present invention is applied to the processing device for processing the wafer W has been described, but it is also possible to apply the present invention to another processing device capable of preventing the processing waste from being solidified.

As described above, the present invention has an effect that the processing waste can be prevented from sticking to the inside of the apparatus, and the work piece can be continuously processed. In particular, the work piece is processed. It is useful for processing equipment.

1 CMP polishing equipment (processing equipment)
40 Turntable 41 Holding Table 46 Water Case 47 Bottom Plate (of Water Case) 48 Drainage Port 51 Processing Means 70 Brush S Slurry W Wafer (Workpiece)

Claims (1)

A turntable that can rotate about its center, a holding table that holds a work piece that is arranged at an equal angle around the center of the turntable, and a processing means that processes the work piece that is held by the holding table. And a water case that has an opening that exposes the turntable, accommodates the turntable, receives the processing waste liquid containing the processing waste that has processed the workpiece flowing down from the turntable, and discharges it from the drain port. ,
The bottom plate of the water case includes an inclined surface on the drain port side, which is inclined lower than the opposite side of the drain port with the center of the turntable interposed therebetween.
The turntable is provided with a brush having a bristle tip facing the bottom plate of the water case on a side surface, and the brush is rotated on the inclined surface by the rotation of the turntable and stays on the inclined surface of the water case. A processing device which stirs the processing waste to be swirled, flows down the inclined surface together with the processing waste liquid, and drains from the drain port .

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