CN210897222U - Substrate wet processing apparatus and recycle ring - Google Patents

Abstract

The present disclosure provides a substrate wet processing apparatus and a recycle ring. A substrate wet processing apparatus includes a turntable, a liquid supply device, a liquid recovery device, and a plurality of gas recovery devices. The spin stand is configured to place a substrate. A liquid supply is configured to apply a process liquid to the substrate. The liquid recovery device includes a recovery loop configured to collect the process liquid and its mixed gas-liquid mixture. The recovery ring comprises a plurality of areas and a plurality of pumping openings, and one pumping opening is correspondingly arranged in one area. And the gas recovery devices are respectively and correspondingly connected with the pumping holes of the recovery ring so as to collect the gas-liquid mixture in the corresponding area of the recovery ring.

Description

Substrate wet processing apparatus and recycle ring

Technical Field

The present disclosure relates to a wet processing apparatus, and more particularly, to a substrate wet processing apparatus and a recycle ring.

Background

In the process of a semiconductor substrate, a plurality of processing steps including wet processing such as etching and cleaning are required for an element mounting surface of the semiconductor substrate. With the increasing complexity of semiconductor substrate processes, a substrate wet processing machine has been developed, which uses a rotary table corresponding to a plurality of liquid recycling modules. The substrate wet processing machine table can apply a plurality of different chemical liquids to the substrate on the rotating table, and the chemical liquids are collected through the corresponding recovery modules. Various metal layers or other material thin film layers on the semiconductor substrate can be cleaned and etched by applying different chemical liquids.

In a conventional wet processing apparatus, the recycle ring is designed with a single pumping hole. However, when a conventional wet substrate processing tool is used to clean and etch a large area of substrate, the volume of the gas generated by the process reaction is very large. The single pumping port design does not allow for the discharge of such large volumes of gas that cannot be effectively exhausted outside the process chamber through the recovery ring. Therefore, the residual gas is retained in the recycling ring or the chamber of the substrate wet processing machine, which affects the substrate cleaning efficiency, even causes the waste gas to flow back to pollute the substrate.

In view of the above, it is desirable to provide a substrate wet processing apparatus and a recycling ring to solve the problems in the prior art.

SUMMERY OF THE UTILITY MODEL

In order to solve the above-mentioned problems of the prior art, an object of the present disclosure is to provide a substrate wet processing apparatus and a recycling ring, which can solve the problem that a large amount of large gas cannot be discharged due to a single pumping design of a conventional recycling ring by a design of a single recycling ring and a plurality of gas recycling devices.

To achieve the above object, the present disclosure provides a substrate wet processing apparatus including a turntable, a liquid supply device, a liquid recovery device, and a plurality of gas recovery devices. The spin stand is configured to place a substrate. A liquid supply is disposed above the turntable and is configured to apply a process liquid to the substrate. And a liquid recovery device circumferentially disposed around the rotary table and movable in a vertical direction relative to the rotary table, wherein the liquid recovery device comprises a recovery ring configured to collect the process liquid and a gas-liquid mixture mixed therewith, and the recovery ring comprises a plurality of regions and a plurality of pumping ports, and one of the pumping ports is correspondingly disposed in one of the regions. And the gas recovery devices are respectively and correspondingly connected with the pumping holes of the recovery ring so as to collect the gas-liquid mixture in the corresponding area of the recovery ring.

In a preferred embodiment, each of the gas recovery devices includes a blower, a vent pipe, and a gas collection box. The air box comprises a first connecting port and a second connecting port, wherein the first connecting port is connected with one of the pumping ports of the recovery rings, so that the gas-liquid mixture in the recovery rings enters the inside of the air box through the first connecting port. The exhaust pipe is connected with the second connecting port of the air box. A gas collection tank is connected to the exhaust pipe and configured to collect the gas-liquid mixture for discharge.

In a preferred embodiment, the liquid recovery device includes a plurality of recovery rings stacked in the vertical direction, and each of the gas recovery devices includes a plurality of wind boxes and a plurality of exhaust pipes, and the wind boxes are connected to the gas collecting box through the exhaust pipes, wherein the wind boxes are respectively connected to the gas exhaust ports of the same region of the recovery rings.

In a preferred embodiment, the recycling loop comprises a plurality of baffles configured to divide the recycling loop into the plurality of zones, and the gas-liquid mixture in any two adjacent zones cannot flow through each other through the baffles.

In a preferred embodiment, the recovery ring further comprises a receiving opening and a divider plate. The receiving port is aligned with the rotary table. The separation plate is arranged in the recovery ring to separate an inner ring space and an outer ring space, wherein the inner ring space receives the process liquid entering from the receiving opening and the gas-liquid mixture mixed by the process liquid, the separation plate blocks the process liquid from flowing from the inner ring space to the outer ring space, and a plurality of through holes are formed in the separation plate, so that the gas-liquid mixture in the inner ring space enters the outer ring space through the plurality of through holes, and the plurality of blocks are arranged in the outer ring space.

In a preferred embodiment, the recovery ring further comprises a liquid collection port in communication with the inner ring space configured to allow the process liquid to drain from the liquid collection port.

In a preferred embodiment, the recovery ring further comprises an annular upper cover, an annular bottom plate, and an outer annular wall. The annular bottom plate and the annular upper cover are correspondingly arranged. The outer ring wall is connected with the outer periphery of the annular upper cover and the outer periphery of the annular bottom plate, the plurality of pumping ports are arranged on the outer ring wall and are correspondingly connected with the plurality of gas recovery devices, the separation plate is arranged between the annular upper cover and the annular bottom plate, and the receiving port is arranged between the inner periphery of the annular upper cover and the inner periphery of the annular bottom plate.

In a preferred embodiment, the liquid supply device comprises a plurality of nozzles.

The present disclosure also provides a recycle ring for a substrate wet processing apparatus, including an annular upper cover, an annular bottom plate, a receiving opening, and an outer annular wall. The annular bottom plate and the annular upper cover are correspondingly arranged. A receiving opening is located between the inner periphery of the annular upper cover and the inner periphery of the annular base plate and is aligned with the turntable. And the outer annular wall is connected with the outer periphery of the annular upper cover and the outer periphery of the annular bottom plate, and is provided with a plurality of pumping holes.

In a preferred embodiment, the recycling ring further includes a plurality of stoppers disposed between the annular upper cover and the annular bottom plate, and configured to divide the recycling ring into the plurality of regions, and one of the pumping holes is disposed in one of the regions.

Compared with the prior art, the substrate wet processing equipment disclosed by the invention has the advantages that the single recovery ring is adopted to be connected with the plurality of gas recovery devices, so that the air extraction amount of the recovery ring can be enhanced, and the problem that the gas-liquid mixture after reaction is retained in the recovery ring due to insufficient air extraction amount is solved. Furthermore, through the design that a plurality of extraction openings of retrieving the ring adopt equal interval each other, can make the extraction volume of retrieving the ring evenly disperse in four gas recovery device, and then avoid because of the extraction volume is uneven, the gas-liquid mixture that leads to after the reaction is detained in a certain corner of retrieving the ring.

Drawings

FIG. 1 shows a schematic view of a substrate wet processing station in accordance with a preferred embodiment of the present disclosure.

Fig. 2 shows a schematic view of a substrate wet processing apparatus according to a preferred embodiment of the present disclosure.

Fig. 3 shows a partial perspective view of a substrate wet processing apparatus according to a preferred embodiment of the present disclosure.

FIG. 4 is a partial perspective view illustrating a recovery ring and a liquid recovery device of the substrate wet processing apparatus of FIG. 3.

Fig. 5 is a partial sectional view showing the substrate wet processing apparatus of fig. 3.

Detailed Description

In order to make the aforementioned and other objects, features and advantages of the present disclosure comprehensible, preferred embodiments accompanied with figures are described in detail below.

Referring to fig. 1, a schematic diagram of a substrate wet processing station 1 according to a preferred embodiment of the present disclosure is shown. The substrate wet processing station 1 is suitable for processing a large-sized substrate. For example, in a fan-out square panel level package (fan-out square level package) process, a square substrate is wet etched or cleaned by a substrate processing apparatus. In order to increase the throughput, the size of the substrate has been increased in recent years, for example, the size of the area of the substrate used at present has reached 600mm × 600 mm. The substrate wet processing station 1 includes a feeding port 2, a discharging port 3, a first conveyor 4, a second conveyor 5, and a plurality of substrate wet processing apparatuses 6. The substrate to be processed enters the substrate wet processing workstation 1 through the feeding port 2. The first transfer device 4 transfers the substrate to the second transfer device 5, and then the second transfer device 5 transfers the substrate to one of the substrate wet processing apparatuses 6 according to the process requirements. Specifically, in the present disclosure, different substrate wet processing apparatuses 6 respectively use different chemical solutions (such as acid, alkali, organic solvent, etc.) and perform gas collection and discharge by independent pumping systems, so as to avoid the gas of the different chemical solutions from generating an interaction reaction, which affects industrial safety.

Referring to fig. 2, a schematic diagram of a substrate wet processing apparatus 6 according to a preferred embodiment of the present disclosure is shown. The substrate wet processing apparatus 6 includes a liquid supply device 61 and a rotation table 62. The substrate 9 to be processed is placed on the rotating table 62. In the present embodiment, the top of the rotating table 62 includes a vacuum chuck, and the substrate 9 may be fixed on the top of the rotating table 62 by the suction force applied by the vacuum chuck. The rotating table 62 is provided with a driving mechanism for driving the rotating table 62 to rotate around the shaft. In other embodiments, the wafer may be fixed on the turntable by other methods, such as a clamping device. Further, a liquid supply device 61 is provided above the turntable 62 for applying a process liquid to the substrate 9. In the present disclosure, when the substrate wet processing apparatus 6 is used to clean or etch a large-area substrate 9, a sufficiently large amount of process liquid must be supplied. Therefore, the chemical supplying rotating arm (chemical supplying swing arm) of the liquid supplying apparatus 61 includes a plurality of nozzles (nozzles) 611 so that the process liquid can be instantly and evenly distributed on the large-area substrate 9. On the other hand, the liquid supply device 61 may apply a plurality of process liquids to the substrate 9. Specifically, the liquid supply device 61 also includes a plurality of liquid transfer lines. The nozzle 611 is disposed to be aligned with the top of the rotary table 62, and one ends of the plurality of liquid transfer lines are connected to the nozzle 611 and the other ends are respectively connected to supply ends of different process liquids. By this design, the liquid supply device 61 can be controlled to apply the corresponding process liquid to the substrate 9 on the turntable 62 according to the process requirement, so as to perform the operations of etching or cleaning the substrate 9.

Referring to fig. 3, a partial perspective view of a substrate wet processing apparatus 6 according to a preferred embodiment of the present disclosure is shown. The substrate wet processing apparatus 6 further includes a liquid recovery device 63 and four gas recovery devices 64. A liquid recovery device 63 is circumferentially arranged around the turntable 62 for collecting and discharging process liquid spun off the surface of the substrate 9 on the turntable 62 due to centrifugal forces. Four gas recovery devices 64 are correspondingly connected to the liquid recovery device 63 for discharging the collected gas-liquid mixture. The specific structure of the liquid recovery device 63 and the gas recovery device 64 of the present embodiment will be described in detail later. On the other hand, the liquid recovery device 63 is connected to the lifting device to control the liquid recovery device 63 to move up and down along a vertical direction relative to the rotating table 62. Further, since the four gas recovery devices 64 are connected to the liquid recovery device 63, when the liquid recovery device 63 is lifted, the four gas recovery devices 64 are lifted or lowered together.

As shown in fig. 3, the liquid recovery apparatus 63 of the present disclosure includes three recovery rings, i.e., a first recovery ring 631, a second recovery ring 632, and a third recovery ring 633, which are stacked in a vertical direction. In other embodiments, a different number of recycle loops may be used, without limitation. The first, second, and third recovery rings 631, 632, 633 are configured to collect a corresponding one of the process liquids and a mixed gas-liquid mixture thereof. The first recycle ring 631, the second recycle ring 632, and the third recycle ring 633 are synchronously moved by the control of the elevating device, such that the designated first recycle ring 631, the designated second recycle ring 632, or the designated third recycle ring 633 is moved to be aligned with the turntable 62, wherein the alignment means that the liquid receiving port of one of the first recycle ring 631, the second recycle ring 632, or the designated third recycle ring 633 is adjacent to the substrate 9 on the turntable 62, such that when the liquid supply device 61 applies the process liquid to the substrate 9 on the turntable 62 and the turntable 62 rotates, the process liquid thrown off by the centrifugal force on the surface of the substrate 9 on the turntable 62 can be collected by the adjacent one of the first recycle ring 631, the second recycle ring 632, or the third recycle ring 633. That is, the substrate wet processing apparatus 6 of the present disclosure is a cleaning and etching apparatus having a movable liquid recovery device 63, which can keep the substrate 9 on the turntable 62 horizontally fixed without moving up and down. When the substrate wet processing process is performed, the designated recycling ring is controlled to move to the alignment rotating table 62 according to the executed steps, and then the specific process liquid is sprayed onto the surface of the substrate 9 by the liquid supply device 61 above the substrate 9, and the substrate 9 is rotated by the rotating table 62 to collect the specific process liquid and the mixed gas-liquid mixture thereof.

Referring to fig. 4, a partial perspective view of the recycling ring and the liquid recycling device of the substrate wet processing apparatus 6 of fig. 3 is shown. Fig. 4 illustrates the first recovery ring 631 positioned at the first level. It should be understood that the remaining second and third recovery rings 632, 633 have substantially the same structure as the first recovery ring 631. As shown in fig. 3 and 4, the first recovery ring 631 includes an annular upper cover 6301, an annular bottom plate 6302, an outer annular wall 6303, a partition plate 6304, four stoppers 6306, a receiving port 6307, a liquid collecting port 6308, and four suction ports 6309. The annular upper cover 6301 is disposed to correspond to the annular bottom plate 6302. Preferably, the annular bottom plate 6302 of the upper recovery ring serves as the annular upper cover 6301 of the lower recovery ring, so that the space inside each recovery ring is maximized, the material used for the liquid recovery device 63 is saved, and the overall volume of the liquid recovery device 63 is effectively reduced. An outer annular wall 6303 of the first recovery ring 631 is connected to an outer peripheral edge of the annular upper cover 6301 and an outer peripheral edge of the annular bottom plate 6302. The annular upper cover 6301, the annular bottom plate 6302, and the outer annular wall 6303 are connected to each other and define an inner space of the first recovery ring 631. The receiving opening 6307 of the first recovery ring 631 is located between the inner perimeter of the annular upper cover 6301 and the inner perimeter of the annular base plate 6302. When the designated first recycling ring 631 moves to the alignment rotary table 62, the receiving opening 6307 of the first recycling ring 631 is aligned with the rotary table 62, so that the first recycling ring 631 can receive the corresponding process liquid and the mixed gas-liquid mixture thereof through the receiving opening 6307.

As shown in fig. 4, the partition plate 6304 of the first recovery ring 631 is disposed inside the first recovery ring 631 to partition the inner space of the first recovery ring 631 into an inner annular space 6310 and an outer annular space 6311. The inner annular space 6310 is used to receive the process liquid and its mixed gas-liquid mixture entering from the receiving opening 6307, and the process liquid is prevented from flowing from the inner annular space 6310 to the outer annular space 6311 by the obstruction of the partition plate 6304. The partition plate 6304 is formed with a plurality of through holes 6305 such that the gas-liquid mixture in the inner annular space 6310 can enter the outer annular space 6311 through the plurality of through holes 6305.

As shown in fig. 4, the four stoppers 6306 of the first recovery ring 631 are configured to divide the first recovery ring 631 into four regions, i.e., a first region 6312, a second region 6313, a third region 6314, and a fourth region 6315. Specifically, four stoppers 6306 are provided in the outer ring space 6311, and are connected to the ring-shaped upper cover 6301 and the ring-shaped bottom plate 6302 so that the gas-liquid mixtures in the adjacent two regions cannot flow through each other through the stoppers 6306. Four suction ports 6309 are provided in the outer annular wall 6303. It should be noted that one of the pumping ports 6309 is correspondingly disposed in one of the areas 6312 and 6315 of the first recycling ring 631. In the present disclosure, the number of the pumping holes 6309 corresponds to the number of the stoppers 6306, and in other embodiments, other numbers of the pumping holes 6309 and the stoppers 6306 may be used, but not limited thereto. Preferably, the four areas 6312 and 6315 separated by the four stoppers 6306 are similar or equal in size. Furthermore, the four air extraction openings 6309 are preferably spaced at equal intervals, so that a uniform suction force can be applied to the substrate, and the substrate is prevented from being etched unevenly due to the process liquid on the substrate being deflected to one side by the atmospheric air flow in a single direction during the etching operation of the substrate.

As shown in fig. 4, the liquid collection port 6308 of the first recovery ring 631 communicates with the inner ring space 6310 and is configured to allow the process liquid to be discharged from the liquid collection port 6308. Specifically, the liquid collection port 6308 is located at the lowest point of the horizontal position of the first recovery ring 631 such that the process liquid collected by the first recovery ring 631 flows by gravity to the liquid collection port 6308. The liquid collecting port 6308 of the first recovery ring 631 is connected to a corresponding recovery pipe, and the collected process liquid is discharged or recovered. For example, as shown in fig. 5, the third recycle ring 633 is connected to a recycle pipe 6316, and the process liquid collected by the third recycle ring 633 is discharged through a path 71. Alternatively, the reclamation pipe 6316 may be connected to the circulation system to return the processed process liquid to the liquid supply device of the substrate wet processing apparatus again.

As shown in FIG. 3, the substrate wet processing apparatus of the present disclosure is provided with four gas recycling devices 64 corresponding to the number of the pumping ports 6309 of each recycling ring 631 and 633. Moreover, the four gas recycling devices 64 are correspondingly connected to the four pumping holes 6309 of each recycling ring 631-633 respectively, so as to collect the gas-liquid mixture in the corresponding region of the recycling ring 631-633. In the present embodiment, each gas recycling device 64 comprises three wind boxes 641 and 643, three exhaust pipes 644 and 646, and a gas collecting box 647, wherein the number of the wind boxes 641 and 643 and the exhaust pipes 644 and 646 corresponds to the number of the recycling rings 631 and 633. The first windbox 641 of the first recovery ring 631 is connected to a collector box 647 by a first exhaust pipe 644. The second windbox 642 of the second recovery loop 632 is connected to a plenum 647 via a second exhaust tube 645. The third bellows 643 of the third recovery ring 633 is connected to a collector box 647 through a third exhaust pipe 646. It should be noted that the first to third wind boxes 641 and 643 are respectively connected to the pumping ports of the same region of the first to third recycling rings 631 and 633. That is, a single gas recovery device 64 is used to collect the gas-liquid mixture in a single region of each of the recovery rings 631 and 633.

Referring to fig. 5, a partial cross-sectional view of the substrate wet processing apparatus 6 of fig. 3 is shown. Fig. 5 is a diagram illustrating a third wind box 643 and a third exhaust pipe 646 connected to a third recovery ring 633. It should be understood that the structures of the remaining windboxes and exhaust pipes are substantially the same as those of the third windbox 643 and the third exhaust pipe 646. In the present embodiment, the third recovery ring 633 includes four third windboxes 643 and four third exhaust pipes 646. The third bellows 643 includes an upper surface 6431, a lower surface 6432, a side surface 6433, a first connection port 6434, a second connection port 6435, and a cavity 6436. An upper face 6431 of the third bellows 643 is disposed opposite the lower face 6432, and a side face 6433 is located between the upper face 6431 and the lower face 6432. The upper surface 6431, lower surface 6432, and side surfaces 6433 interconnect to form a cavity 6436. A side surface 6433 of the third bellows 643 is formed with a first connection port 6434, and a lower surface 6432 is formed with a second connection port 6435. The first connection port 6434 of the third wind box 643 is connected to the suction port of the third recovery ring 633. As shown in fig. 5, the gas recovery device 64 applies negative pressure to the third recovery ring 633, so that the third recovery ring 633 and the inside of the gas recovery device 64 generate gas flow like the path 72. Specifically, the gas-liquid mixture inside the third recovery ring 633 enters the inside of the cavity 6436 of the third windbox 643 through the first connection port 6434. The third exhaust pipe 646 is connected to the second connection port 6435 of the third windbox 643, and further delivers the gas-liquid mixture to the gas collection box 647. The gas collection tank 647 may discharge the gas-liquid mixture collected from the first through third recovery rings 631 and 633.

In summary, the substrate wet processing apparatus according to the present disclosure can enhance the pumping amount of the recycling ring by adopting the design of connecting the recycling ring with the plurality of gas recycling devices, thereby preventing the gas-liquid mixture after the reaction from staying in the recycling ring due to insufficient pumping amount. Furthermore, through the design that a plurality of extraction openings of retrieving the ring adopt equal interval each other, can make the extraction volume of retrieving the ring evenly disperse in four gas recovery device, and then avoid because of the extraction volume is uneven, the gas-liquid mixture that leads to after the reaction is detained in a certain corner of retrieving the ring.

The foregoing is merely a preferred embodiment of the present disclosure, and it should be noted that modifications and refinements may be made by those skilled in the art without departing from the principle of the present disclosure, and these modifications and refinements should also be regarded as the protection scope of the present disclosure.

Claims (10)

1. An apparatus for wet processing a substrate, comprising:

a rotation stage configured to place a substrate;

a liquid supply device disposed above the spin stage and configured to apply a process liquid to the substrate;

a liquid recovery device circumferentially disposed around the rotary table and movable in a vertical direction relative to the rotary table, wherein the liquid recovery device comprises a recovery ring configured to collect the process liquid and a gas-liquid mixture mixed therewith, and the recovery ring comprises a plurality of regions and a plurality of pumping ports, and one of the pumping ports is correspondingly disposed in one of the regions; and

and the gas recovery devices are respectively and correspondingly connected with the pumping holes of the recovery ring so as to collect the gas-liquid mixture in the corresponding area of the recovery ring.

2. The apparatus of claim 1, wherein each of the gas recovery devices comprises:

the air box comprises a first connecting port and a second connecting port, wherein the first connecting port is connected with the pumping port of one of the recovery rings, so that the gas-liquid mixture in the recovery rings enters the interior of the air box through the first connecting port;

the exhaust pipe is connected with the second connecting port of the air box; and

a gas collection tank connected to the exhaust pipe and configured to collect the gas-liquid mixture to discharge it.

3. The substrate wet processing apparatus of claim 2, wherein the liquid recovery device includes a plurality of the recovery rings stacked in the vertical direction, and each of the gas recovery devices includes a plurality of the bellows and a plurality of the exhaust pipes, and the plurality of bellows are connected to the gas collection box through the plurality of exhaust pipes, wherein the plurality of bellows are respectively connected to the pumping ports of the same region of the plurality of recovery rings.

4. The substrate wet processing apparatus of claim 1, wherein the recovery ring comprises a plurality of blocks configured to divide the recovery ring into the plurality of zones, and the gas-liquid mixtures in any two adjacent zones cannot flow through each other through the blocks.

5. The substrate wet processing apparatus of claim 4, wherein the recycle ring further comprises:

a receiving port aligned with the rotary table; and

a partition plate disposed inside the recovery ring to partition an inner ring space and an outer ring space, wherein the inner ring space receives the process liquid entering from the receiving port and the gas-liquid mixture mixed therewith, and the partition plate blocks the process liquid from flowing from the inner ring space to the outer ring space, and a plurality of through holes are formed in the partition plate such that the gas-liquid mixture in the inner ring space enters the outer ring space through the plurality of through holes, wherein the plurality of blocks are disposed in the outer ring space.

6. The apparatus of claim 5, wherein the recovery ring further comprises a liquid collection port in communication with the inner ring space and configured to allow the process liquid to drain from the liquid collection port.

7. The substrate wet processing apparatus of claim 5, wherein the recycle ring further comprises:

an annular upper cover;

the annular bottom plate is arranged corresponding to the annular upper cover; and

and an outer ring wall connected to an outer peripheral edge of the annular upper cover and an outer peripheral edge of the annular bottom plate, wherein the plurality of pumping ports are provided on the outer ring wall and connected to the plurality of gas recovery devices, respectively, wherein the partition plate is provided between the annular upper cover and the annular bottom plate, and the receiving port is provided between an inner peripheral edge of the annular upper cover and an inner peripheral edge of the annular bottom plate.

8. The apparatus of claim 1, wherein the liquid supply device comprises a plurality of nozzles.

9. A recycle ring for a substrate wet processing apparatus, comprising:

an annular upper cover;

the annular bottom plate is arranged corresponding to the annular upper cover;

a receiving opening between an inner periphery of the annular upper cover and an inner periphery of the annular base plate and aligned with the turntable; and

and the outer annular wall is connected with the outer periphery of the annular upper cover and the outer periphery of the annular bottom plate, and is provided with a plurality of pumping holes.

10. The recycling ring for a substrate wet processing apparatus according to claim 9, further comprising a plurality of stoppers disposed between the annular upper cover and the annular base plate, configured to divide the recycling ring into a plurality of regions, and wherein a pumping port is disposed in one of the regions.

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