Plasma treatment device

Abstract

This plasma treatment device has: a first member impregnated with oil; a second member; a heating part that heats the first member; and a gap that is provided between the first member and the second member, that extends from a plasma treatment space to an external space, and that is filled with the oil leaking from the first member as a result of the first member being heated by the heating part.

Description

Plasma processing equipment

[0001] The present disclosure relates to a plasma processing apparatus.

[0002] For example, Patent Document 1 discloses that an O-ring is provided as a sealing member to separate a reduced pressure environment from an atmospheric pressure environment.

[0003] Japanese Patent Application Laid-Open No. 2020-043328

[0004] The present disclosure provides a technology that allows for long term sealing.

[0005] According to one aspect of the present disclosure, there is provided a plasma processing apparatus having a first member impregnated with oil, a second member, a heating unit that heats the first member, and a gap provided between the first member and the second member, the gap communicating from a plasma processing space to an external space, and filled with the oil leaking from the first member as the first member is heated by the heating unit.

[0006] The present disclosure provides a technology that allows for long term sealing.

[0007] FIG. 1 is a diagram illustrating the configuration of a plasma processing system including a plasma processing apparatus according to this embodiment. FIG. 2 is a diagram illustrating a sealing structure in the plasma processing apparatus according to this embodiment. FIG. 3 is a diagram illustrating a modified example of the sealing structure in the plasma processing apparatus according to this embodiment. FIG. 4 is a diagram illustrating details of the plasma processing apparatus according to this embodiment. FIG. 5 is a diagram illustrating details of the plasma processing apparatus according to this embodiment. FIG. 6 is a diagram illustrating a sealing structure in a comparative example.

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In this specification and the drawings, substantially identical components are designated by the same reference numerals, and redundant description will be omitted. To facilitate understanding, the scale of each part in the drawings may differ from the actual scale. Directions such as parallel, right-angled, orthogonal, horizontal, vertical, up / down, left / right, and the like are permitted to a degree that does not impair the effects of the embodiments. The shape of corners is not limited to right angles and may be rounded. Parallel, right-angled, orthogonal, horizontal, and vertical may include approximately parallel, approximately right-angled, approximately orthogonal, approximately horizontal, and approximately vertical.

[0009] <Plasma Processing System> An example of the configuration of a plasma processing system will be described below. Fig. 1 is a diagram illustrating the configuration of a plasma processing system including a plasma processing apparatus 1, which is an example of a plasma processing apparatus according to this embodiment.

[0010] The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a controller 2. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 has at least one gas inlet for supplying at least one processing gas to the plasma processing space 10s and at least one gas outlet for exhausting gas from the plasma processing space 10s. The sidewall 10a is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the plasma processing chamber 10 housing.

[0011] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region (substrate support surface) 111a for supporting a substrate (wafer) W and an annular region (ring support surface) 111b for supporting the ring assembly 112. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. In one embodiment, the main body 111 includes a base and an electrostatic chuck. The base includes a conductive member. The conductive member of the base functions as a lower electrode. The electrostatic chuck is disposed on the base. The upper surface of the electrostatic chuck has the substrate support surface 111a. The ring assembly 112 includes one or more annular members. At least one of the one or more annular members is an edge ring. Although not shown, the substrate support 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck, the ring assembly 112, and the substrate to a target temperature. The temperature control module may include a heater, a heat transfer medium, a flow path, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111 a.

[0012] The showerhead 13 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The process gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The showerhead 13 also includes a conductive member. The conductive member of the showerhead 13 functions as an upper electrode. In addition to the showerhead 13, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0013] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

[0014] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power), such as a source RF signal and a bias RF signal, to the conductive member of the substrate support 11 and / or the conductive member of the showerhead 13. This causes plasma to be formed from at least one process gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit configured to generate plasma from one or more process gases in the plasma processing chamber 10. Furthermore, by supplying a bias RF signal to the conductive member of the substrate support 11, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0015] In one embodiment, the RF power supply 31 includes a first RF generator 31a and a second RF generator 31b. The first RF generator 31a is coupled to the conductive members of the substrate support 11 and / or the conductive members of the showerhead 13 via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 13 MHz to 150 MHz. In one embodiment, the first RF generator 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to the conductive members of the substrate support 11 and / or the conductive members of the showerhead 13. The second RF generator 31b is coupled to the conductive members of the substrate support 11 via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). In one embodiment, the bias RF signal has a frequency lower than that of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 400 kHz to 13.56 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies, and the generated bias RF signals or signals may be supplied to the conductive members of the substrate support 11. Also, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0016] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to a conductive member of the substrate support 11 and configured to generate a first DC signal. The generated first bias DC signal is applied to the conductive member of the substrate support 11. In one embodiment, the first DC signal may be applied to another electrode, such as an electrode in an electrostatic chuck. In one embodiment, the second DC generator 32b is connected to a conductive member of the showerhead 13 and configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the showerhead 13. In various embodiments, at least one of the first and second DC signals may be pulsed. The first and second DC generating units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided instead of the second RF generating unit 31b.

[0017] The exhaust system 40 may be connected to a gas exhaust port 10e provided in, for example, the bottom 10b of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is regulated by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0018] The controller 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform the various processes described in this disclosure. The controller 2 may be configured to control each element of the plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the controller 2 may be included in the plasma processing apparatus 1. The controller 2 may include, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a storage unit 2a2, and a communication interface 2a3. The processing unit 2a1 may be configured to perform various control operations based on programs stored in the storage unit 2a2. The storage unit 2a2 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[0019] The sealing structure of the plasma processing apparatus according to this embodiment will be described below: Fig. 2 is a diagram illustrating the sealing structure of a plasma processing apparatus 1, which is an example of the plasma processing apparatus according to this embodiment.

[0020] The sealing structure between members constituting the processing vessel in the plasma processing apparatus 1 will be described as an example.

[0021] The plasma processing apparatus 1 includes a first member 100, a second member 110, and a heating unit 120. The plasma processing apparatus 1 also has a gap 130 between the first member 100 and the second member 110.

[0022] [First Member 100] The first member 100 constitutes, for example, a part of the plasma processing chamber 10. The first member 100 is a member impregnated with oil. The first member 100 is a member whose interior is intentionally impregnated with oil.

[0023] The first member 100 may be made of, for example, metal or resin. The material of the first member 100 may be appropriately selected depending on the required strength, etc.

[0024] The oil impregnated into the first member 100 is, for example, ester oil, fluorine oil, mineral oil, or poly-α-olefin oil. The kinematic viscosity of the oil impregnated into the first member 100 is, for example, 40 square millimeters per second (mm ２ / s) or more than 75 square millimeters per second (mm ２ The ISO viscosity grade number of the oil impregnated into the first member 100 may be, for example, ISO VG 46 or ISO VG 68.

[0025] The amount of oil impregnated into the first member 100 should be an amount that will not cause a shortage of oil during the period of use. For example, by impregnating the first member 100 with a large amount of oil that can be impregnated, the risk of oil depletion can be reduced even after long-term use.

[0026] The first member 100 includes a heating unit 120 therein that heats the first member 100. When the first member 100 is heated by the heating unit 120, oil contained in the first member 100 precipitates. The oil precipitated from the first member 100 by being heated fills the gap 130.

[0027] The first member 100 has a step 100s that protrudes upward toward the reduced pressure space LPS. By providing the first member 100 with the step 100s that protrudes upward toward the reduced pressure space LPS (the plasma processing space 10s side), it is possible to prevent the oil filled in the gap 130 from flowing out into the reduced pressure space LPS. The step may also be provided on the atmospheric pressure space APS side (external space side). Furthermore, if oil does not flow out, the step may be omitted.

[0028] The first member 100 has groove-shaped recesses 100g and recesses 100h. The recesses 100g receive the protrusions 110p of the second member 110. The recesses 100h receive the protrusions 110q of the second member 110. In the plasma processing apparatus 1, the protrusions 110p receive the recesses 100g and the protrusions 110q receive the recesses 100h, so that the gap 130 forms a labyrinth structure LBR.

[0029] The number of recesses is not limited to the above example, and may be one, or three or more.

[0030] [Second member 110] The second member 110 constitutes, for example, a part of the plasma processing chamber 10. The second member 110 has convex portions 110p and 110q formed in a convex shape. The convex portion 110p fits into the concave portion 100g of the first member 100. The convex portion 110q fits into the concave portion 100h of the first member 100. In the plasma processing apparatus 1, the convex portion 110p fits into the concave portion 100g and the convex portion 110q fits into the concave portion 100h, so that the gap 130 forms a labyrinth structure LBR.

[0031] The labyrinth structure of the gap 130 may be formed by providing convex portions in the first member 100 and concave portions in the second member 110. The labyrinth structure of the gap 130 may also be formed by providing convex portions and concave portions alternately in the first member 100 and the second member 110.

[0032] [Heating section 120] The heating section 120 heats the first member 100. The heating section 120 is, for example, an electric heating wire. The heating section 120 is supplied with power from a power source 120a. The heating section 120 generates heat when power is supplied from the power source 120a. When the heating section 120 generates heat, the first member 100 is heated.

[0033] The plasma processing apparatus 1 controls the power source 120 a so that the oil impregnated in the first member 100 leaks out from the surface of the first member 100 by heating the first member 100 with the heating unit 120 .

[0034] The heating unit 120 heats the first member 100 to a temperature in the range of 150°C to 180°C, for example.

[0035] The heating unit 120 is provided inside the first member 100. Although the heating unit 120 is provided inside the first member 100, the heating unit 120 may be provided outside the first member 100 as long as it can heat the first member 100. For example, the heating unit 120 may be provided in the second member 110. FIG. 3 is a diagram illustrating a modified example of the sealing structure in the plasma processing apparatus 1, which is an example of the plasma processing apparatus according to this embodiment. As shown in FIG. 3, the heating unit 120 may be provided inside the second member 110. Furthermore, for example, the heating unit 120 may be provided in both the first member 100 and the second member 110. Furthermore, for example, the heating unit 120 may heat the first member 100 using heat rays such as infrared rays while being separated from the first member 100.

[0036] [Gap 130] The gap 130 connects the reduced pressure space LPS, which is connected to the plasma processing space 10s, to the atmospheric pressure space APS. In other words, the gap 130 connects the plasma processing space 10s to the external space. When the first member 100 is heated by the heating unit 120, oil precipitates from the first member 100. The oil precipitated from the first member 100 fills the gap 130. When the oil precipitated from the first member 100 fills the gap 130, the plasma processing apparatus 1 can seal the reduced pressure space LPS and the atmospheric pressure space APS at the portion of the gap 130 where the oil is filled. By filling and sealing the gap 130 with the oil precipitated from the first member 100, the plasma processing apparatus 1 can maintain airtightness between the reduced pressure space LPS and the atmospheric pressure space APS.

[0037] Furthermore, when the first member 100 is heated, oil is replenished into the gap 130. By appropriately replenishing the oil from the first member 100 into the gap 130, the plasma processing apparatus 1 can maintain airtightness for a long period of time.

[0038] <Summary> The plasma processing apparatus according to this embodiment can stably seal the space between the plasma processing space and the atmospheric pressure space for a long period of time. Because the gap is filled with oil, the plasma processing apparatus according to this embodiment can seal the space between the plasma processing space and the atmospheric pressure space even if the roughness of each surface between the first member 100 and the second member 110 is relatively large. The plasma processing apparatus according to this embodiment can reduce processing costs because the roughness of each surface between the first member 100 and the second member 110 can be large.

[0039] Furthermore, according to the plasma processing apparatus of this embodiment, the sealing performance can be further improved by having a labyrinth structure between the first member 100 and the second member 110. Furthermore, according to the plasma processing apparatus of this embodiment, the labyrinth structure between the first member 100 and the second member 110 can retain oil precipitated from the first member 100 for a long period of time.

[0040] As a comparative example, a sealing structure using an O-ring will be described. FIG. 6 is a diagram illustrating the sealing structure in the comparative example. The comparative example includes an O-ring 150 between a first member 100z and a second member 110z. Since the O-ring 150 deteriorates over a long period of use, the comparative example requires increased maintenance costs for replacing the O-ring 150. Furthermore, the use of the O-ring 150 increases the number of parts in the comparative example.

[0041] The plasma processing apparatus according to this embodiment eliminates the need to replace deteriorated parts such as O-rings, thereby reducing maintenance costs. Furthermore, the plasma processing apparatus according to this embodiment reduces the number of parts and reduces manufacturing costs.

[0042] Furthermore, when sealing the gap between the first member 100z and the second member 110z with the O-ring 150, it is necessary to smoothly process each surface between the first member 100z and the second member 110z to ensure airtightness. Since each surface between the first member 100z and the second member 110z needs to be smoothly processed, the processing cost increases in the comparative example.

[0043] According to the plasma processing apparatus of this embodiment, the gap is filled with oil, so that the finishing accuracy of the surface can be reduced. By reducing the finishing accuracy, the plasma processing apparatus of this embodiment can reduce processing costs.

[0044] Furthermore, for example, grease may be applied between the first member 100z and the second member 110z to seal the gap. When grease is applied to seal the gap, the grease may deteriorate or run out. When the grease deteriorates or runs out, it is necessary to apply grease again, which increases maintenance costs.

[0045] According to the plasma processing apparatus of this embodiment, the first member is heated to fill the gap with oil, thereby reducing maintenance costs.

[0046] Here, a more specific example of the plasma processing apparatus 1 will be described. Figures 4 and 5 each illustrate details of the plasma processing apparatus 1, which is an example of the plasma processing apparatus according to this embodiment. Figure 5 is an enlarged schematic view of the upper wall 10a3 in Figure 4. For example, the oil-impregnated first member is applied to the sealing surface of a chamber body provided on the outside of the plasma processing chamber 10.

[0047] The plasma processing apparatus 1 includes a side wall 10a, which includes an outer wall 10a1 and an inner wall 10a2. The outer wall 10a1 is provided on the outer side of the side wall 10a relative to the plasma processing space 10s. The outer wall 10a1 is the outermost wall of the side wall 10a. The inner wall 10a2 is provided on the side of the side wall 10a facing the plasma processing space 10s. The plasma processing apparatus 1 also includes an upper wall 10a3 on the outer wall 10a1. In other words, the upper wall 10a3 is provided on the side wall 10a, more specifically, on the upper part of the outer wall 10a1. The upper wall 10a3 is also provided between the side wall 10a and the shower head 13, more specifically, between the outer wall 10a1 and the shower head 13. The plasma processing apparatus 1 also includes plate portions 14a and 14b on the inner wall 10a2 that sandwich the heater 14 from above and below. Furthermore, the plasma processing apparatus 1 includes a shower head 13 on the plate portion 14b and the upper wall 10a3.

[0048] The upper wall 10a3 is an oil-impregnated member. A heater 10h is provided inside the upper wall 10a3. A power source (not shown) is connected to the heater 10h. When power is supplied to the heater 10h, the oil impregnated in the upper wall 10a3 precipitates. The oil precipitated from the upper wall 10a3 fills a gap 131 between the upper wall 10a3 and the shower head 13 and a gap 132 between the outer wall 10a1 and the upper wall 10a3. The oil precipitated from the upper wall 10a3 fills the gap 131 and the gap 132, thereby sealing the gaps between the upper wall 10a3 and the shower head 13 and between the outer wall 10a1 and the upper wall 10a3. The heater 10h may be provided in the outer wall 10a1 or the shower head 13, as long as it can heat the upper wall 10a3.

[0049] A labyrinth structure LBR1 is formed in a gap 131 between the upper wall 10a3 and the shower head 13. The gap 131 communicates with the plasma processing space 10s, for example, through a gap between the plate portion 14b and the shower head 13. A labyrinth structure LBR2 is formed in a gap 132 between the outer wall 10a1 and the upper wall 10a3. The gap 132 communicates with the plasma processing space 10s, for example, through a gap between the plate portion 14a and the inner wall 10a2.

[0050] In the above example, for example, the upper wall 10a3 is an example of a first member, and the outer wall 10a1 and the shower head 13 are each an example of a second member.

[0051] In the above example, the inner wall 10a2 is a single layer, but multiple layers of inner walls may be provided. The upper wall 10a3 may extend up to the upper part of the inner wall 10a2. Furthermore, in the above example, the upper wall 10a3 is provided between the outer wall 10a1 and the shower head 13, but a separate member may be provided outside the shower head 13, and the upper wall 10a3 may be provided between the separate member and the outer wall 10a1.

[0052] The above example is an example of application of the first member impregnated with oil, but the first member may be used in a different location. Also, in the above example, the member forming the gap may be a different member.

[0053] The plasma processing apparatus according to the present embodiment disclosed herein should be considered to be illustrative in all respects and not restrictive. The above-described embodiments can be modified and improved in various ways without departing from the spirit and scope of the appended claims. The features described in the above-described embodiments can be configured in other ways as long as they are not inconsistent, and can be combined as long as they are not inconsistent.

[0054] The above-disclosed embodiments include, for example, the following aspects.

[0055] (Supplementary Note 1) A plasma processing apparatus comprising: a first member impregnated with oil; a second member; a heating unit that heats the first member; and a gap provided between the first member and the second member, the gap communicating from a plasma processing space to an external space, the gap being filled with the oil leaking from the first member as the first member is heated by the heating unit.

[0056] (Supplementary Note 2) The plasma processing apparatus according to Supplementary Note 1, wherein the gap has a labyrinth structure.

[0057] (Supplementary Note 3) The plasma processing apparatus according to either Supplementary Note 1 or Supplementary Note 2, wherein the first member has a step on a side of the plasma processing space.

[0058] (Supplementary Note 4) The plasma processing apparatus according to any one of Supplementary Note 1 to Supplementary Note 3, wherein the heating unit is provided on the first member.

[0059] (Supplementary Note 5) The plasma processing apparatus according to any one of Supplementary Note 1 to Supplementary Note 4, wherein the heating unit is provided on the second member.

[0060] (Supplementary Note 6) The plasma processing apparatus according to any one of Supplementary Note 1 to Supplementary Note 5, wherein the oil has a kinematic viscosity at a temperature of 40°C of 40 to 75 square millimeters per second.

[0061] (Supplementary Note 7) The plasma processing apparatus according to any one of Supplementary Notes 1 to 6, further comprising a sidewall, wherein the first member is provided on an upper portion of the sidewall.

[0062] (Supplementary Note 8) The plasma processing apparatus according to Supplementary Note 7, wherein the sidewall comprises an inner wall provided on a side of the plasma processing space and an outer wall provided on an outer side of the plasma processing space, and the first member is provided on an upper part of the outer wall.

[0063] (Supplementary Note 9) The plasma processing apparatus according to Supplementary Note 7, further comprising: a shower head; and the first member is provided between the shower head and the side wall.

[0064] This application claims priority from basic patent application No. 2023-128291, filed with the Japan Patent Office on August 7, 2023, the entire contents of which are incorporated herein by reference.

[0065] REFERENCE SIGNS LIST 1 Plasma processing apparatus 10a1 Outer wall 10a3 Upper wall 10h Heater 10s Plasma processing space 13 Shower head 100 First member 100g, 100h Recessed portion 100s Step 110 Second member 110p, 110q Convex portion 110z Second member 120 Heating portion 130, 131, 132 Gap APS Atmospheric pressure space LBR, LBR1, LBR2 Labyrinth structure LPS Reduced pressure space OIL Oil

Claims

1. A plasma processing apparatus comprising: a first member impregnated with oil; a second member; a heating unit that heats the first member; and a gap provided between the first member and the second member, the gap communicating from a plasma processing space to an external space, the gap being filled with the oil leaking from the first member as the first member is heated by the heating unit.

2. The plasma processing apparatus according to claim 1, wherein the gap has a labyrinth structure.

3. The plasma processing apparatus according to claim 1, wherein the first member has a step on the side of the plasma processing space.

4. The plasma processing apparatus according to claim 1, wherein the heating section is provided on the first member.

5. The plasma processing apparatus according to claim 1, wherein the heating section is provided on the second member.

6. The plasma processing apparatus according to claim 1, wherein the oil has a kinetic viscosity at a temperature of 40° C. of 40 to 75 square millimeters per second.

7. The plasma processing apparatus according to claim 1, further comprising a side wall, the first member being provided on an upper portion of the side wall.

8. The plasma processing apparatus according to claim 7, wherein the side wall comprises an inner wall provided on the side of the plasma processing space and an outer wall provided on the outside of the plasma processing space, and the first member is provided on an upper portion of the outer wall.

9. The plasma processing apparatus according to claim 7, further comprising a shower head, the first member being provided between the shower head and the side wall.

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