JP2003214578A - Rotary joint and plating device using this rotary joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary joint for allowing miniaturization, and preventing mixing of a particle in a processing fluid flowing inside. <P>SOLUTION: This rotary joint 25 has a tubular stator 43, and a tubular rotor 44. The stator 43 includes a body 47, an inner cylinder part 45 projecting from the body 47, an outer cylinder part 46 coaxially arranged with the inner cylinder part 45 around the inner cylinder part 45 by projecting from the body 47, and a leak port 57 for leaking the inside fluid. The rotor 44 has a cylindrical part 50. First clearance 52 is formed between the inner cylinder part 45 and a cylindrical part 50, and second clearance 53 is formed between the outer cylinder part 46 and the cylindrical part 50. A sealing ring 64 including, a pressure contact member 64a and a coil spring 64b is arranged in the second clearance 53. The leak port 57 communicates with the second clearance 53 in the vicinity of the sealing ring 64. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary joint used in a single-wafer plating apparatus for plating a semiconductor substrate while rotating it, and a plating apparatus using the same.

[0002]

2. Description of the Related Art For example, in the process of manufacturing a semiconductor device, the surface of a semiconductor substrate may be subjected to treatments such as plating, etching and cleaning. These treatments are performed while rotating the semiconductor substrates one by one so that the surface of the semiconductor substrate is uniformly processed. The semiconductor substrate is rotated about the spindle while being held by the holding member having the spindle.

When the processing fluid is supplied to the rotating semiconductor substrate from the side where the support shaft of the holding member is arranged toward the center of rotation, the processing fluid must be supplied through the support shaft. That is, the rotating support shaft must also serve as a pipe for supplying the processing fluid. Therefore, it is necessary to interpose a rotary joint between the stationary storage source in which the processing fluid to be supplied is stored and the rotating support shaft. The rotary joint includes a stator (fixed member) and a rotor (rotating member) through which a processing fluid can flow. A solid sealing ring is interposed between the stator and the rotor so that the processing fluid does not flow out between the stator and the rotor. When the rotor rotates with respect to the stator, the sealing ring is rubbed against the stator and the rotor, and the particles generated thereby may be mixed with the processing fluid and supplied to a processing object such as a semiconductor substrate.

A prior art for solving this problem is disclosed in, for example, Japanese Patent Laid-Open No. 11-307502. In this prior art, a supply tank for storing the processing liquid to be supplied to the substrate is arranged below the turntable that holds and rotates the substrate. A hollow nozzle shaft is integrally inserted into a rotary shaft that supports the rotary table. The lower end of the nozzle shaft is configured to be submerged in the processing liquid in the supply tank, and the upper end of the nozzle shaft is provided with an injection nozzle facing the lower surface of the substrate.

By pressurizing the gas existing above the processing liquid in the supply tank, the processing liquid rises in the nozzle shaft and is supplied from the injection nozzle to the lower surface of the substrate held on the rotary table. At this time, the nozzle shaft is rotated together with the rotary shaft, but since the processing liquid is present between the nozzle shaft and the fixed member such as the supply tank, particles are not generated.

[0006]

However, in this prior art, the mechanism for connecting the fixed member and the rotating member includes the supply tank and the rotating shaft, and the connecting portion between the fixing member and the rotating member is independent. It was difficult to make parts that were made, and it was not easy to use. Further, when the liquid level of the processing liquid is lowered and the lower end of the nozzle shaft is higher than the liquid level, the liquid cannot be sent into the nozzle shaft, so that a large amount of the processing liquid cannot be continuously supplied. Further, in order to continuously supply a large amount of processing liquid, a large supply tank or a mechanism for controlling the liquid surface (for example, detecting the height of the liquid surface and, if necessary, supplying the processing liquid into the supply tank). Supply mechanism). For these reasons, downsizing of the device is difficult and the usability is poor.

On the other hand, when the mechanism for connecting the fixed member and the rotating member is arranged above the substrate to be processed and the processing fluid is supplied from above the substrate to be processed, the mechanism for connecting the fixed member and the rotating member is moved up and down. You may need to move it. In this case, it is indispensable to reduce the size of the mechanism that connects the fixed member and the rotating member, but the above-described prior art cannot meet such a demand. Further, in order to pressurize the gas existing above the processing liquid in the supply tank, the supply tank must be hermetically sealed to some extent, so that it is difficult to completely make the rotating member and the fixing member non-contact with each other. . Therefore, it has been difficult to completely eliminate the mixing of particles into the processing liquid.

Therefore, an object of the present invention is to provide a rotary joint which can be miniaturized. Another object of the present invention is to provide a rotary joint in which particles are prevented from being mixed into a processing fluid flowing inside. Still another object of the present invention is to provide a plating apparatus that can be downsized.

Still another object of the present invention is to provide a plating apparatus which prevents particles from being mixed into a processing fluid.

[0010]

The invention according to claim 1 for solving the above-mentioned problems, comprises a tubular stator (43) having an internal space (56) and a tubular stator fitted to the tubular stator (43). An internal space (45) that communicates with the internal space of the tubular stator to form a main flow path (70).
and a tubular rotor (4) having a) and forming a gap (52, 53) communicating with the main flow path between the tubular rotor and the tubular stator.
4), a sealing ring (64) arranged in the gap and surrounding the main flow path to seal between the tubular stator and the tubular rotor, and the tubular stator,
A rotary joint (25), comprising: a leak port (57) for leaking fluid in the gap from a position closer to the main flow path than the sealing ring.

The alphanumeric characters in parentheses represent corresponding components in the embodiments described later. The same applies in this section below. This rotary joint can be used by connecting a fixed pipe to the tubular stator and a rotating pipe to the tubular rotor. When a fluid is flowed from the fixed pipe into the inner space of the tubular stator, the fluid flows through the inner space of the tubular rotor into the rotating pipe. In this way, the processing fluid can be flowed between the fixed pipe and the rotating pipe. This rotary joint is an independent part,
Since it does not require a large tank or the like, it can be constructed in a small size and can be easily attached to the upper end of the rotating pipe or the like. Further, since the processing fluid can be continuously supplied through this rotary joint, it is easy to use.

The leak port may be open to the atmosphere of atmospheric pressure, for example. In this case, when pressure is applied to the fluid flowing through the main flow path, a part of the fluid flows through the gap to the leak port having a lower pressure. When the tubular rotor rotates, the sealing ring will
It rubs against the tubular stator and tubular rotor to generate particles (dust). The sealing ring that causes the generation of the particles is arranged in the gap branched from the main flow path.
Since the generated particles are discharged to the outside from the leak port together with the processing fluid, they are not mixed in the main flow path and supplied to the supply destination of the processing fluid.

The processing fluid may be a liquid such as a chemical solution or pure water, or a gas such as nitrogen gas. By narrowing the width of the gap or increasing the length of the gap (length along the flow direction of the processing fluid flowing in the gap), a large pressure loss can be generated in the processing fluid existing in the gap. it can. In this case, in order to increase the flow rate of the processing fluid flowing through the main flow channel, even if a large pressure is applied to the processing fluid flowing through the main flow channel, no large pressure (load) is applied to the sealing ring. This extends the useful life of the sealing ring.

Further, by increasing the pressure loss in the gap, the flow rate of the processing fluid flowing in the gap can be reduced, and the consumption amount of the processing fluid can be reduced. By narrowing the width of the gap or increasing the length of the gap, it is possible to obtain the effect of preventing particles from moving backward through the gap and mixing into the main flow path. The gap may include, for example, a gap portion of 0.1 mm or less as described in claim 2. In this case, the effect of the pressure loss described above can be satisfactorily obtained.

According to a third aspect of the present invention, the tubular stator comprises a first tubular member (45) and a second tubular member (46) arranged around the first tubular member and coaxially with the first tubular member. ), The tubular rotor is arranged coaxially with the first tubular member and the second tubular member between the first tubular member and the second tubular member to form the fitting. A first gap (52) comprising a cylindrical member (50), said gap being formed between said first tubular member and said cylindrical member and communicating with said main flow path; and said second tubular member and said 3. A second gap (53) formed between a cylindrical member and communicating with the first gap, wherein the sealing ring is arranged in the second gap. It is a rotary joint.

When a portion of the processing fluid flows from the main flow path to the leak port, the processing fluid flows from the first gap to the second gap. Since the sealing ring is arranged in the second gap, the processing fluid cannot flow beyond the sealing ring in the second gap and is discharged to the outside through the leak port. According to the present invention, the width of the first gap (the distance between the first tubular member and the cylindrical member) and the width of the second gap (the distance between the second tubular member and the cylindrical member) can be easily and independently changed. can do. This makes it possible to set the width of the first gap to be narrow so as to obtain the above-described effect, and to set the second gap to be wide so that the sealing ring can be easily arranged.

Further, by disposing the sealing ring, which is a main source of generation of particles, in the second gap apart from the main flow passage, it is possible to further prevent the particles from being mixed into the main flow passage. The invention according to claim 4 is the rotary joint according to claim 3, wherein the first tubular member and the second tubular member are integrally formed. When the first gap is configured to have a narrow width as described above, the first tubular member and the cylindrical member may come into contact with each other even if the width changes slightly. When the width of the second gap is not constant,
The sealing ring may not be able to provide a good seal.

According to the present invention, since the first tubular member and the second tubular member are integrally formed, it is easy to keep the gap between them at a predetermined value. Therefore, the first gap and the second gap are set to be predetermined. It is easy to keep the width. A bearing may be provided in the second gap on the side opposite to the processing fluid side with respect to the sealing ring. In this case, since the cylindrical member is axially supported by the sealing ring and the bearing at the two positions with respect to the second tubular member, the widths of the first gap and the second gap can be more accurately maintained.

According to a fifth aspect of the present invention, the sealing ring is arranged inside the pressure contact member (64a) in pressure contact with the tubular stator and the tubular rotor, and the pressure contact member is disposed inside the pressure contact member. The rotary joint according to any one of claims 1 to 4, further comprising a rotor and an elastic member (64b) biasing the tubular stator. By using a material having high wear resistance as the pressure contact member and a material having large elasticity as the elastic member, it is possible to obtain a sealing ring having a long service life and good sealing performance.

The pressure contact member may be made of a fluororesin, for example. Thereby, even if there is no lubricant or the like between the pressure contact member and the tubular stator and the tubular rotor and they directly contact with each other, the pressure contact member can have good wear resistance. As the elastic member, for example, a coil spring (a spiral spring) as described in claim 7 can be used.
The invention according to claim 8 is a substrate holding / rotating mechanism (1, 10) for holding and rotating a substrate (W), and the substrate holding / rotating mechanism, which is provided in the substrate holding / rotating mechanism, rotates together with the substrate, and the processing fluid is provided on one surface of the substrate. And a supply pipe (2) for supplying the processing fluid from the processing fluid supply source to the rotation pipe.
7), the rotary joint according to any one of claims 1 to 7 for connecting the rotary pipe and the supply pipe, and a plating solution supply means (33, 41) for supplying a plating solution to the other surface of the substrate. It is a plating apparatus characterized by having.

The rotary pipe rotates together with the substrate holding and rotating mechanism, but the rotary joint allows the processing fluid to flow between the rotary pipe and the fixed supply pipe. According to the present invention, it is possible to supply the plating solution to one surface of the rotating substrate while simultaneously supplying the processing fluid such as pure water to the other surface of the substrate. As a result, it is possible to prevent the plating solution from wrapping around to the other surface and perform plating only on a desired region of the substrate. By using the rotary joint according to any one of claims 1 to 7, the plating apparatus can be made compact and easy to use, and particles can be prevented from being mixed into the processing fluid.

The plating solution supply means may be a plating tank. In this case, by causing a flow of the plating solution from the bottom to the top in the plating tank to cause the plating solution to overflow from the plating tank, the plating solution may slightly rise from the edge of the plating tank. it can. The lower surface of the substrate can be brought into contact with the surface of the plating solution in this state for plating. The processing fluid may be an inert gas (eg, nitrogen gas) or the like. In this case, the substrate surface wet with pure water or the like can be dried.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, referring to the accompanying drawings,
Embodiments of the present invention will be described in detail. Figure 1
FIG. 1 is a schematic sectional view showing an overall configuration of a substrate processing apparatus that employs a rotary joint according to an embodiment of the present invention. The substrate processing apparatus is a plating apparatus for performing electrolytic plating on the lower surface of the wafer W, and is a plating tank 33 for containing a processing liquid, and a wafer W held above the plating tank 33 for holding and rotating the wafer W. Spin base 1 is included.

The spin base 1 includes an annular mask member 3 in a plan view, a plurality of columns 5 connected to one side of the mask member 3, and a rotary tube 7 connected to the plurality of columns 5. ing. The mask member 3 is an elastic seal member 1 for adhering to the peripheral portion of the lower surface of the wafer W.
3, a cathode electrode 11 for contacting the wafer W to apply a negative voltage, and a drain port 3e communicating with the outer peripheral surface of the mask member 3 from below the cathode electrode 11 (on the seal member 13 side).

A pressing member 15 for pressing the non-processed surface of the wafer W is provided inside the spin base 1. The pressing member 15 includes a disc-shaped contact member 17 and a rotary pipe 19 vertically provided at the rotation center of the contact member 17. Around the lower surface of the abutting member 17, the lower part (the seal member 13
A pressing portion 17c protruding to the side) is formed. A vertical channel 19 a is formed inside the rotary pipe 19. The abutting member 17 is radially formed with a plurality of lateral flow paths 17d extending from directly below the rotary pipe 19 and opening to the outer peripheral surface of the pressing portion 17c. These plural lateral channels 17d
Are connected to the vertical flow path 19a. Vertical channel 19a
A gas such as nitrogen gas or a liquid such as pure water can be passed through the lateral flow path 17d.

The rotating pipe 19 is connected to an elevating mechanism 9 for raising and lowering the rotating pipe 19, and a rotary drive mechanism 10 for rotating the rotating pipe 19 around its axis. The rotary pipe 7 can be fixed and released from the rotary pipe 19, and when fixed, can move up and down and rotate together with the rotary pipe 19. As a result, the spin base 1 can be moved up and down between a standby position having a height as shown in FIG. 1 and a processing position located below the standby position. When the rotary pipe 7 is not fixed to the rotary pipe 19, the mask member 3 is movable with respect to the pressing member 15, and the wafer W carried into the spin base 1 is transferred to the mask member 3 by the pressing portion 17c. It can be pressed against and pinched.

The spin base 1 is rotatable about a rotary shaft (not shown) orthogonal to the rotary pipe 7 and the rotary pipe 19, and the mask member 3 and the pressing portion 17 are plated as shown in FIG. It can be moved between a facing position facing the bath 33 and a non-facing position not facing the plating bath 33. The wafer W is applied to the mask member 3 and the pressing member 15.
An operation such as sandwiching between and can be performed at the non-opposing position. A plating tank 33 having a diameter slightly smaller than the diameter of the wafer W is provided below the spin base 1, and a recovery tank 35 is provided so as to surround the plating tank 33.
An opening 33a is formed on the bottom surface of the plating tank 33, and an annular anode electrode 37 for applying a positive voltage is arranged around the opening 33a in the plating tank 33. From the bottom of the recovery tank 35 to the opening 33a of the plating tank 33
A pipe 39 is communicatively connected to the pipe 39, and the plating solution L in the recovery tank 35 is supplied upward into the plating tank 33 by a pump 41 interposed in the pipe 39.

Further outside the recovery tank 35, the plating tank 3 is provided.
A drainage tank 42 having a peripheral edge higher than that of the drainage tank 3 and the recovery tank 35 is provided. The drainage tank 42 is connected to a waste fluid tank or the like via a drainage line. Hereinafter, a method of plating processing using this substrate processing apparatus will be described. When the plating solution L is circulated by the pump 41, the liquid level of the plating solution L is slightly higher than the edge of the plating tank 33 as shown in FIG. The wafer W is held and rotated by the pressing member 15 and the mask member 3 so that the processing surface Ws is the lower surface. Then, pure water is sent from above the vertical channel 19a. The pure water passes through the lateral flow path 17d and then the pressing portion 17c.
Is discharged from the opening of the outer peripheral surface of the wafer W, flows on the upper surface of the outer peripheral portion of the wafer W, and is then discharged through the liquid discharge port 3e and the liquid discharge tank 42.

When the spin base 1 is lowered in this state,
The wafer W contacts the plating solution L while rotating. When electricity is applied between the anode electrode 37 and the cathode electrode 11, the processing surface Ws (lower surface) of the wafer W is uniformly plated. Further, by supplying pure water to the peripheral portion of the upper surface of the wafer W at the time of plating, it is possible to prevent the plating solution from flowing around,
Plating can be satisfactorily applied only to a predetermined area of the treated surface Ws. By switching the nitrogen gas as the fluid flowing in the vertical flow path 19a, the peripheral portion of the upper surface of the wafer W wet with pure water can be dried.

FIG. 2 is a schematic sectional view showing the structure of the spin base 1. A pulley 21 is attached to the rotary pipe 19, and the pulley 21 and the pulley 2 of the motor 23 are attached.
A belt 24 is stretched between the two. As a result, the rotary pipe 19 is rotated by the rotational driving force of the motor 23. A rotary joint 25 is attached to the upper end of the rotary pipe 19. A supply pipe 27 and a leak pipe 28 are connected to the rotary joint 25. The supply pipe 27 includes valves 29 and 30.
A nitrogen gas source and a pure water source are connected to each other via the rotary joint 25, and nitrogen gas and pure water can be supplied to the vertical flow path 19a of the rotary pipe 19 via the rotary joint 25. . The flow rates of nitrogen gas and pure water are
It can be adjusted by valves 29 and 30, respectively.

An end portion of the supply pipe 27 on the side opposite to the rotary joint 25 side is arranged at a position lower than the rotary joint 25, and a valve 31 is connected to this end portion. By opening the valve 31, the supply pipe 27
The liquid inside can be drained. Leak piping 2
At the end opposite to the rotary joint 25 side of 8,
The ejector 32 is connected. The ejector 32 can forcibly cause the fluid in the leak pipe 28 to flow from the rotary joint 25 toward the ejector 32 by the action of the compressed air. When the ejector 32 is not used, the end portion of the leak pipe 28 on the ejector 32 side is open to the atmosphere (atmospheric pressure).

FIG. 3 is a schematic sectional view showing the structure of the rotary joint 25. Rotary joint 25
Includes a stator 43 connected to the supply pipe 27 and the leak pipe 28, and a rotor 44 connected to the rotary pipe 19. The stator 43 includes a body 47 and a body 4.
7 includes an inner cylindrical portion 45 protruding from the body 7, and an outer cylindrical portion 46 protruding from the body 47 and arranged coaxially with the inner cylindrical portion 45 around the inner cylindrical portion 45. The body 47, the inner tubular portion 45, and the outer tubular portion 46 are integrally formed. In the body 47, the joint 4 for connecting the supply pipe 27 in the direction orthogonal to the direction in which the inner tubular portion 45 and the outer tubular portion 46 extend.
8 and a joint 49 for connecting the leak pipe 28
Is provided. From the joint 48 and the joint 49 to the inside of the body 47, respectively, the processing fluid supply holes 56.
And the leak port 57 extends.

The rotor 44 includes a joint 51 for connecting the rotary pipe 19, and a cylindrical portion 50 extending coaxially with the rotary pipe 19 connected to the joint 51. A through hole 62 is formed along the central axis of the rotor 44.
The joint 51 includes a connecting pipe 58 and a flange 60 that are externally threaded. An inner thread is formed on the inner surface of the end of the rotary pipe 19 so that it can be screwed into the outer thread of the connecting pipe 58. The position of the tightened end of the rotary pipe 19 is regulated by the flange 60. Between the rotary pipe 19 and the flange 60,
A packing 61 made of fluororesin is interposed.

The cylindrical portion 50 is fitted in the annular space between the inner tubular portion 45 and the outer tubular portion 46 of the body 47 coaxially with the inner tubular portion 45 and the outer tubular portion 46. Processing fluid supply hole 56,
The internal space 45a of the inner tubular portion 45 and the through hole 62 of the rotor 44 are in communication with each other, and form a main flow path 70 that guides the processing fluid supplied from the supply pipe 27 to the rotary pipe 19. A first gap 52 is formed between the inner cylinder portion 45 and the cylindrical portion 50, and a second gap 53 is formed between the outer cylinder portion 46 and the cylindrical portion 50. The width of the first gap 52 (the distance between the inner cylindrical portion 45 and the cylindrical portion 50) is about 50 μm, but it is wider near the tip of the cylindrical portion 50.
Width of the second gap 53 (distance between the outer cylinder portion 46 and the cylinder portion 50)
Is a few mm. The main flow path 70 and the first gap 52 communicate with each other through a first communication portion 54 near the tip of the inner cylinder portion 45, and the first gap 52 and the second gap 53 communicate with each other near the tip of the cylinder portion 50. The parts 55 communicate with each other. Also, the second communication part 55
A leak port 57 communicates with a part of the. The first gap 52, a part of the second gap 53, and the leak port 57.
Form a leak passage 71, and the main passage 70 and the leak pipe 28 communicate with each other via the leak passage 71.

In the second gap 53, the first spacer 63, the sealing ring 64 and the second spacer 63 are arranged in this order from the side closer to the second communicating portion 55.
Spacer 65, C ring 66, two bearings 67,
A third spacer 68 is arranged. Except for the C ring 66, all have a closed ring shape and surround the cylindrical portion 50. The sealing ring 64 is sandwiched between the first spacer 63 and the second spacer 65, and its axial position is fixed with respect to the outer cylinder portion 46. The first spacer 63 and the second spacer 65 are in contact with the outer cylindrical portion 46, but are not in contact with the cylindrical portion 50. The bearing 67 has a fixed axial position with respect to the cylindrical portion 50, and rotatably supports between the cylindrical portion 50 and the outer cylindrical portion 46. The C ring 66 is fitted in a shallow groove provided at a predetermined position of the cylindrical portion 50.

The sealing ring 64 is a pressure-contact member 64 made of fluororesin and having a U-shaped cross section, which is open toward the second communicating portion 55.
a, a coil spring (coil spring) 64b arranged in the pressure contact member 64a, and a pressing member 64c that covers a part of the pressure contact member 64a in the opening direction. Pressure contact member 64
a is the coil spring 64 due to the elasticity of the coil spring 64b.
It is urged outwardly around b and is in contact with the outer cylinder portion 46 and the cylinder portion 50. Coil spring 64
b is made of a material having resistance to the processing liquid used. The pressing member 64c is a coil spring 64b.
Is pressed so as not to come off from the pressure contact member 64a.

An external thread is formed on the outer surface of the outer cylindrical portion 46 near the tip thereof. A fixing ring 69 having an inner thread corresponding to the outer thread is fastened to the outer side of the outer tube portion 46. The fixing ring 69 is provided at the end on the rotor 44 side,
It has a collar 69a protruding inward. The collar 69 a extends between the third spacer 68 and the flange 60. When the stator 43 and the rotor 44 are fitted to each other to assemble the rotary joint 25, the fixing ring 69 is tightened into the outer tubular portion 46, so that the C ring 6
6, the third spacer 68 and the bearing 67 can be guided to a predetermined position in the axial direction.

Since the end portion of the leak pipe 28 on the ejector 32 side is normally at atmospheric pressure and the processing fluid flowing through the main flow passage 70 is normally under pressure, a part of the processing fluid flowing through the main flow passage 70 is present. Flows into the leak passage 71 having a lower pressure. Part of the processing fluid flowing through the leak channel 71 is
Although it extends from the second communication portion 55 to the second gap 53, the sealing ring 64 prevents the movement and prevents the bearing 67 from leaking. When the rotary pipe 19 rotates, the rotor 44 also rotates. The rotor 44 is supported by the stator 43 via the sealing ring 64 and the bearing 67, and thus can freely rotate with respect to the stator 43. Rotor 4
By the rotation of 4, the pressure contact member 64a rubs against one or both of the outer cylinder portion 46 and the cylinder portion 50. The pressure contact member 64a made of fluororesin has good wear resistance, but particles are slightly generated (dust generation).

In the leak channel 71, the processing fluid flows from the first gap 52 toward the leak port 57, so that particles generated in the sealing ring 64 are discharged to the leak pipe 28 through the leak channel 71. It Therefore, particles are not mixed into the processing fluid flowing through the main flow path 70, and the processing fluid containing particles is not supplied to the wafer W. When the flow rate of the processing fluid flowing from the main channel 70 to the leak channel 71 is small, the ejector 32
(See FIG. 2), the flow rate may be forcibly increased.
In addition, since the width of the first gap 52 is set to be as narrow as 50 μm, it is difficult for the particles to move toward the main channel 70.

Due to the narrow width of the first gap 52, a large pressure loss occurs in the processing fluid existing in this portion. Therefore, even if a large pressure is applied to the processing fluid in the main channel 70 in order to increase the flow rate of the processing fluid flowing in the main channel 70, a large pressure (load) is not applied to the sealing ring 64. Therefore, the service life of the sealing ring 64 is extended. When the processing fluid is the processing liquid, the second gap 5
The treatment liquid present in 3 also serves to lubricate and cool the sealing ring 64. This also increases the service life of the sealing ring 64.

Particles of the processing fluid flowing through the leak passage 71 can be discharged to the outside at a small flow rate. By reducing the width of the first gap 52, the first gap 52
It is possible to reduce the flow rate of the processing fluid flowing in the chamber and reduce the consumption of the processing fluid such as the processing liquid. Since the inner tubular portion 45 and the outer tubular portion 46 are formed integrally with the body 47,
The distance between the inner tubular portion 45 and the outer tubular portion 46 is accurately maintained at a predetermined value. Since the cylindrical portion 50 is supported by the sealing ring 64 and the two bearings 67 at three locations with respect to the outer tubular portion 46, the distance between the cylindrical portion 50 and the outer tubular portion 46, that is, the width of the second gap is also. , Exactly kept at a predetermined value. Therefore, the distance between the cylindrical portion 50 and the inner cylindrical portion 45, that is, the width of the first gap 52 is also accurately maintained at a predetermined value, and the cylindrical portion 50 and the inner cylindrical portion 45 do not come into contact with each other.

As described above, this rotary joint 2
5 can be constructed as one small, independent part, through which a continuous supply of process fluid is possible. Therefore, the substrate processing apparatus (plating apparatus) including the rotary joint 25 can be made compact. Further, the rotary joint 25 can be used in any orientation (posture), and there is no restriction when attached to the plating apparatus.

The pressure loss in the first gap 52 may be increased by increasing the length of the first gap 52 along the axial direction. This also makes it difficult for particles to mix into the main flow path 70. The number of cylindrical portions (inner cylinder portion 45 and outer cylinder portion 46) of the stator 43 may be three or more, and the number of cylindrical portions (cylindrical portion 50) of the rotor 44 may be two or more. Good. That is, the stator 43 and the rotor 44 may include more cylindrical portions than the above-described embodiment, and may include many gaps communicating in a zigzag manner. Plural leak channels 71 and leak ports 57 may be provided.

In addition, various changes can be made within the scope of the matters described in the claims.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an overall configuration of a substrate processing apparatus in which a rotary joint according to an embodiment of the present invention is adopted.

FIG. 2 is a schematic sectional view showing the structure of the spin base shown in FIG.

FIG. 3 is a schematic sectional view showing a structure of a rotary joint according to an embodiment of the present invention.

[Explanation of symbols]

1 spin base 19 rotating piping 23 motor 25 rotary joint 27 Supply piping 33 plating tank 41 pumps 43 Stator 44 rotor 45 Inner tube 45a Internal space of cylindrical part 46 Outer cylinder 47 body 50 Cylindrical part 52 First gap 53 Second gap 56 Processing fluid supply hole 57 Leakport 64 sealing ring 64a pressure contact member 64b coil spring 70 main flow path 71 Leakage channel W semiconductor wafer

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3H104 JA04 JB04 JC10 JD09 LE02                       LF08                 4K024 BB12 CB01 CB02 CB08 CB11                       CB18 CB22

Claims (8)

[Claims] 1. A tubular stator having an internal space, and an internal space which is fitted into the tubular stator and which communicates with the internal space of the tubular stator to form a main flow path. A tubular rotor forming a gap communicating with the main flow path; a sealing ring disposed in the gap and sealing the main flow path to seal between the tubular stator and the tubular rotor; A rotary joint, comprising: a leak port for leaking fluid in the gap from a position closer to the main flow path than a ring. 2. The rotary joint according to claim 1, wherein the gap includes a gap portion in which the gap between the tubular stator and the tubular rotor is 0.1 mm or less. 3. The tubular stator comprises a first tubular member and a second tubular member arranged coaxially with the first tubular member around the first tubular member, and the tubular rotor comprises: A cylindrical member that is coaxial with the first tubular member and the second tubular member and that is arranged between the first tubular member and the second tubular member to form the fitting; A first gap formed between the first tubular member and the cylindrical member and communicating with the main flow path, and a second gap formed between the second tubular member and the cylindrical member and communicating with the first gap. 3. The rotary joint according to claim 1, wherein the sealing ring is arranged in the second gap. 4. The rotary joint according to claim 3, wherein the first tubular member and the second tubular member are integrally formed. 5. The sealing ring is disposed inside the pressure contact member in pressure contact with the tubular stator and the tubular rotor, and urges the pressure contact member to the tubular stator and the tubular rotor. An elastic member is included, The said 1 thru | or 4 characterized by the above-mentioned.
The rotary joint according to any one of 1. 6. The rotary joint according to claim 5, wherein the pressure contact member is made of fluororesin. 7. The rotary joint according to claim 5, wherein the elastic member is a coil spring. 8. A substrate holding / rotating mechanism that holds and rotates a substrate, a rotary pipe that is provided in the substrate holding / rotating mechanism, rotates with the substrate, and supplies a processing fluid to one surface of the substrate, and a processing fluid supply source. A supply pipe for guiding the processing fluid from the above to the rotary pipe, a rotary joint according to any one of claims 1 to 7 for connecting the rotary pipe and the supply pipe, and a plating solution is supplied to the other surface of the substrate. A plating apparatus comprising: a plating solution supply means.