Substrate processing device and connection assembly

Abstract

This substrate processing device processes a substrate. The substrate processing device comprises: a first member and a second member that are mutually laminated and that have mutually different thermal expansion coefficients; and a connection assembly that extends in parallel to the lamination direction of the first member and the second member and that connects the first member and the second member. The connection assembly has a sliding structure that can slide in a direction orthogonal to the lamination direction when the first member and / or the second member thermally expands.

Description

Substrate processing apparatus and connection assembly

[0001] The present disclosure relates to substrate processing apparatus and docking assemblies.

[0002] Patent Literature 1 discloses a substrate processing apparatus (film formation apparatus) that performs plasma processing such as film formation on a substrate. In this type of substrate processing apparatus, thermal expansion occurs in members provided in a processing chamber due to the influence of plasma during the plasma processing.

[0003] When multiple components have different thermal expansion coefficients, the connecting parts connecting these components are subjected to stress due to the difference in thermal expansion. For this reason, connecting parts connecting components with different thermal expansion coefficients are required to have a structure that can tolerate the difference in thermal expansion.

[0004] JP 2020-17697 A

[0005] The present disclosure provides a technique that can stably connect multiple members with different thermal expansion coefficients.

[0006] According to one aspect of the present disclosure, there is provided a substrate processing apparatus for processing a substrate, comprising: a first member and a second member stacked on each other and having different thermal expansion coefficients; and a connecting assembly extending parallel to the stacking direction of the first member and the second member and connecting the first member and the second member, wherein the connecting assembly has a sliding structure that is slidable in a direction perpendicular to the stacking direction upon thermal expansion of the first member and / or the second member.

[0007] According to one aspect, it is possible to stably connect a plurality of members having different thermal expansion coefficients to each other.

[0008] 1 is a diagram showing the overall configuration of a plasma processing system including a substrate processing apparatus (plasma processing apparatus) according to an embodiment; FIG. 3A is a cross-sectional view showing an enlarged view of the vicinity of the outer periphery of a shower head including a connection assembly; FIG. 3B is a first enlarged view showing the connection assembly when the cooling plate is not thermally expanded; FIG. 3B is a second enlarged view showing the connection assembly when the cooling plate is thermally expanded; and FIG. 3C is a third enlarged view showing the connection assembly when the ceiling member is thermally expanded. FIG. 6A is a first enlarged view showing the connection assembly according to a modified example when the cooling plate is not thermally expanded; and FIG. 6B is a second enlarged view showing the connection assembly according to a modified example when the cooling plate is thermally expanded.

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0010] 1 is a diagram showing the overall configuration of a plasma processing system having a substrate processing apparatus (plasma processing apparatus 1) according to an embodiment. First, an example of the configuration of the plasma processing system will be described with reference to FIG.

[0011] The plasma processing system includes a capacitively coupled plasma processing apparatus 1, which is a substrate processing apparatus, and a controller 2. The plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 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 50. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 50 is disposed above the substrate support 11. In one embodiment, the showerhead 50 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 50, 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 50 and the substrate support 11 are electrically insulated from the plasma processing chamber 10 housing.

[0012] 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.

[0013] The showerhead 50 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 50 has at least one gas supply port 50a, at least one gas diffusion chamber 50b, and multiple gas inlets 50c. The process gas supplied to the gas supply port 50a passes through the gas diffusion chamber 50b and is introduced into the plasma processing space 10s from the multiple gas inlets 50c. The showerhead 50 also includes a conductive member. The conductive member of the showerhead 50 functions as an upper electrode.

[0014] The shower head 50 according to the embodiment has a layered structure in which multiple components are stacked. The multiple components of the shower head 50 include a ceiling component (first component) 51 that forms the ceiling surface of the plasma processing space 10s, and a cooling plate (second component) 52 that is stacked on top of the ceiling component 51.

[0015] The ceiling member 51 is formed in a disk shape and has multiple gas inlet ports 50c along the surface direction (horizontal direction). Furthermore, the ceiling member 51 according to the embodiment is configured as a conductive member (upper electrode) to which a source RF signal, a bias RF signal, etc. are supplied from a power supply 30 (described later). The ceiling member 51 generates plasma from the processing gas in the plasma processing space 10s in response to the supplied source RF signal, bias RF signal, etc. Therefore, the ceiling member 51 is formed of a conductive material. The material of the ceiling member 51 is not particularly limited, but examples thereof include carbon (C: graphite, etc.), silicon (Si), silicon carbide (SiC), and combinations of these materials.

[0016] On the other hand, the cooling plate 52 is formed in a disk shape with a recess, and is stacked on the upper surface of the ceiling member 51 to form a gas diffusion chamber 50b at the boundary with the ceiling member 51. The cooling plate 52 is also provided so as to be in close contact with the ceiling member 51, and has a cooling mechanism (not shown) inside. As a result, heat from the ceiling member 51, which becomes hot due to the heat input from the plasma, is transferred to the cooling plate 52, thereby cooling the ceiling member 51.

[0017] The cooling mechanism of the cooling plate 52 has, for example, a spiral or annular coolant flow path (not shown) extending in the circumferential direction. The cooling mechanism circulates a low-temperature coolant by supplying and discharging it from a chiller unit provided outside the plasma processing chamber 10 to the coolant flow path of the cooling plate 52. Examples of the coolant include cooling water and Galden (registered trademark). The cooling plate 52 is preferably made of a material with high thermal conductivity to cool the ceiling member 51. The material of the cooling plate 52 is not particularly limited, but examples include anodized aluminum and aluminum alloys. In addition to the showerhead 50, the gas introduction unit of the plasma processing chamber 10 may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0018] 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 50 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.

[0019] 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 members of the substrate support 11 and / or the conductive members of the showerhead 50. 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, supplying a bias RF signal to the conductive members of the substrate support 11 generates a bias potential on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0020] 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 50 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 50. 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 lower frequency than 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 are 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.

[0021] 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 50 and configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the showerhead 50. 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.

[0022] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom 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.

[0023] 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 memory 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 memory unit 2a2. The memory 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).

[0024] 2 is an enlarged cross-sectional view showing the vicinity of the outer periphery of the showerhead 50 having the connection assembly 60. As shown in FIG. 2, the showerhead 50 of the plasma processing apparatus 1 is installed on the upper part of the plasma processing chamber 10 with the above-mentioned multiple components (ceiling member 51, cooling plate 52) stacked. For this reason, the showerhead 50 includes multiple connection assemblies 60 that connect the ceiling member 51 and the cooling plate 52 to each other on the outer periphery of the ceiling member 51 and the cooling plate 52.

[0025] As described above, the ceiling member 51 and the cooling plate 52 are made of different materials. Therefore, the thermal expansion coefficients of the ceiling member 51 and the cooling plate 52 are also different. The connecting assembly 60 has a clamping function that clamps and connects the ceiling member 51 and the cooling plate 52 in the up-down direction (vertical direction). Note that the showerhead 50 may be configured by stacking other members in addition to the ceiling member 51 and the cooling plate 52. Depending on the showerhead 50, the connecting assembly 60 is not limited to one that sandwiches two members, but may be configured to sandwich three or more members.

[0026] Specifically, the ceiling member 51 of the showerhead 50 has an attachment step 511 on its outer periphery, radially outward from the ejection surface having the multiple gas inlets 50c, that can be hooked onto the connection assembly 60. The attachment step 511 of the ceiling member 51 is formed thinner than the thickness of the ejection surface portion, and has an annular shape that circumscribes the ceiling member 51.

[0027] Meanwhile, the cooling plate 52 of the shower head 50 has a protruding outer periphery 521 that protrudes radially outward from the main body portion that contacts the ceiling member 51. This protruding outer periphery 521 is formed in an annular shape and is located radially outward of the mounting step 511 of the ceiling member 51. Accommodating holes 522 that accommodate portions (upper portions) of the connecting assemblies 60 are provided in the protruding outer periphery 521 at positions adjacent to the radially outer side of the ceiling member 51. The number of accommodating holes 522 corresponds to the number of connecting assemblies 60 to be installed, and the accommodating holes 522 are arranged at intervals around the circumferential direction of the protruding outer periphery 521.

[0028] The multiple connection assemblies 60 have a portion that engages with the mounting step 511 of the ceiling member 51 and a portion that is inserted into the accommodation hole 522 and engages with the cooling plate 52, clamping the ceiling member 51 and the cooling plate 52. Each connection assembly 60 clamps the ceiling member 51 and the cooling plate 52 at multiple points around the circumference, thereby maintaining a sealed state between the ceiling member 51 and the cooling plate 52. The showerhead 50 may also include an O-ring (not shown) or the like at the boundary between the ceiling member 51 and the cooling plate 52 to airtightly seal the two members.

[0029] Each connection assembly 60 includes a male screw member 61, a disc spring 62, an elastic receiving member 63, an upper sliding seat member 64, a locking member 65, a female screw member 66, a washer 67, a lower sliding seat member 68, a guide member 69, and a female screw holder 70. The plasma processing chamber 10 also includes a protective case 71 that covers the female screw holder 70, and an insulating member 72 that sandwiches the protective case 71 between the protective case 71 and the cooling plate 52.

[0030] The male screw member 61 is a member whose upper portion is received in the receiving hole 522 of the cooling plate 52, while its lower portion exposed from the receiving hole 522 is inserted into the female screw member 66. The male screw member 61 and the female screw member 66 extend parallel to the stacking direction of the ceiling member 51 and the cooling plate 52, and form a fastening structure 73 that threads together. The clamping force of the connecting assembly 60 on the ceiling member 51 and the cooling plate 52 can be adjusted by adjusting the axial length of the threaded engagement between the male screw member 61 and the female screw member 66.

[0031] In detail, the male screw member 61 has a lower screw portion 611 having threads 61a on its outer peripheral surface that screw into the female screw member 66, an intermediate rod portion 612 that is continuous with the upper end of the lower screw portion 611, and a head portion 613 that is provided at the upper end of the intermediate rod portion 612. The head portion 613 also includes a flange 614 that protrudes radially outward from the intermediate rod portion 612, a connecting member 615 that is provided at the axis of the intermediate rod portion 612, and a heat insulating member 616 that is connected to the connecting member 615. The lower screw portion 611, the intermediate rod portion 612, and the flange 614 are integrally molded with one another.

[0032] The lower region of the lower threaded portion 611 is inserted into the female threaded hole 663 of the female threaded member 66, thereby becoming a portion that is directly threaded into the female threaded member 66. The intermediate rod portion 612 has a smooth outer peripheral surface, and the disc spring 62 is disposed around its side. The flange 614 is formed in an annular shape in a plan view and functions as a seat that receives the elastic force of the disc spring 62. The connecting member 615 is housed in a T-shaped hole in a cross-sectional view formed at the axis of the intermediate rod portion 612, and protrudes slightly vertically upward from the intermediate rod portion 612. The heat insulating member 616 covers the protruding connecting member 615 and is fixed to the connecting member 615 to suppress temperature transfer from the cooling plate 52 to the male threaded member 61.

[0033] The disc spring 62 is disposed between the flange 614 of the male screw member 61 and the elastic receiving member 63, and has the function of elastically receiving a load (a load parallel to the stacking direction) applied to both members. For example, the connecting assembly 60 has multiple (five) disc springs 62 stacked vertically, which can alleviate a large load applied in the vertical direction. Furthermore, the disc spring 62 can move integrally with the male screw member 61 by coming into contact with the outer circumferential surface of the intermediate rod portion 612 of the male screw member 61.

[0034] The elastic receiving member 63 is a cylindrical member disposed around the male screw member 61, with one end of the disc spring 62 in contact with its upper end surface. The outer diameter of the elastic receiving member 63 is formed slightly larger than the outer diameter of the flange 614 of the male screw member 61 and the outer diameter of the disc spring 62. For example, the elastic receiving member 63 is preferably formed with an outer diameter in the range of approximately 2 / 3 to 9 / 10 of the inner diameter of the accommodation hole 522. This creates an appropriate gap C1 between the outer surface of the elastic receiving member 63 and the inner surface of the accommodation hole 522 (see FIG. 3A). The gap C1 allows the male screw member 61, the disc spring 62, and the elastic receiving member 63 to slide horizontally (in a direction perpendicular to the stacking direction of the ceiling member 51 and the cooling plate 52).

[0035] The lower end surface of the elastic receiving member 63 is a flat (smooth) sliding surface 631 extending horizontally, and is in contact with the upper sliding seat member 64. The sliding surface 631 allows the elastic receiving member 63 to slide relative to the upper sliding seat member 64.

[0036] The upper sliding seat member 64 is formed in an annular shape with its underside supported by the locking member 65, and is a member that supports the elastic receiving member 63 so that it can move relatively. In other words, the connecting assembly 60 uses the elastic receiving member 63 and the upper sliding seat member 64 to form a sliding structure 74 that is slidable in the horizontal direction perpendicular to the stacking direction. The outer diameter of the upper sliding seat member 64 roughly matches the inner diameter of the accommodation hole 522. This keeps the upper sliding seat member 64 restricted from sliding in the horizontal direction within the accommodation hole 522.

[0037] The upper surface of the upper sliding seat member 64 according to this embodiment is a flat (smooth) sliding surface 641 extending in the horizontal direction. However, the sliding structure 74 is not limited to the sliding surface 631 of the elastic receiving member 63 and the sliding surface 641 of the upper sliding seat member 64, and various other configurations are possible. For example, the sliding structure 74 may be a sliding bearing, to either the elastic receiving member 63 or the upper sliding seat member 64, that has a plurality of rolling elements that are in contact with the sliding surface of the other and can roll.

[0038] The locking member 65 is formed in a circular ring shape in a plan view, and is fitted into an engagement groove formed on the inner circumferential surface of the accommodation hole 522. This locking member 65 is non-detachably fixed to the cooling plate 52, thereby enabling it to stably support the upper sliding seat member 64. In other words, the locking member 65 prevents the male screw member 61, the disc spring 62, the elastic receiving member 63, and the upper sliding seat member 64 from falling out of the accommodation hole 522, and also enables it to elastically support the male screw member 61 in the vertical direction.

[0039] On the other hand, the female screw member 66 is a member that screws into the male screw member 61 in the connection assembly 60, and is formed to be thicker than the male screw member 61. This female screw member 66 has a female screw body 661 that extends vertically, and a flange head 662 that is continuous with the lower end of the female screw body 661. The female screw body 661 and the flange head 662 are molded integrally with each other.

[0040] The female screw body 661 extends linearly in the vertical direction and is formed longer than the lower screw engagement portion 611 of the male screw member 61. An opening of a female screw hole 663 is provided at the upper end of the female screw body 661. The female screw hole 663 is formed to a predetermined depth vertically downward from the opening, and its inner circumferential surface is formed with a screw groove (not shown) into which the thread 61 a of the male screw member 61 can be threaded. In addition, a rotation hole 664 is provided at the lower end surface of the female screw body 661 (see FIG. 3A ), into which a wrench (not shown, such as a hexagonal wrench) is inserted to rotate the female screw member 61.

[0041] The flange head 662 protrudes a short distance radially outward from the lower end of the female screw body 661. A washer 67 is stacked on the upper surface of this flange head 662. The washer 67 is formed in an annular shape, is supported by the flange head 662, and protrudes radially outward beyond the outer circumferential surface of the flange head 662.

[0042] The lower sliding seat member 68 is formed in an annular shape, is supported by a washer 67, and is fitted onto the outer circumferential surface of the female screw body 661. The inner diameter of the lower sliding seat member 68 roughly matches the outer diameter of the female screw body 661. This allows the lower sliding seat member 68 to move integrally with the female screw member 66. Like the upper sliding seat member 64, the lower sliding seat member 68 slidably supports the guide member 69 that is stacked on its upper surface.

[0043] The upper surface of the lower sliding seat member 68 according to this embodiment is a horizontally extending flat (smooth) sliding surface 681. However, the sliding structure 74 of the lower sliding seat member 68 and the guide member 69 is not limited to this, and for example, a sliding bearing having multiple rolling elements may be applied to either the lower sliding seat member 68 or the guide member 69.

[0044] The guide member 69 is supported by the lower sliding seat member 68 and is fitted onto the outer circumferential surface of the female screw body 661. However, the inner diameter of the guide member 69 is formed larger than the outer diameter of the female screw body 661, and a gap C2 is created between the inner circumferential surface of the guide member 69 and the outer circumferential surface of the female screw body 661. This gap C2 allows the female screw holder 70 to slide horizontally relative to the female screw body 661.

[0045] The guide member 69 is formed in a D-shape in plan view, and is inserted into a through-hole 703 (lower hole 703b) of the female screw holder 70, which is also formed in a D-shape (see also FIG. 3A). This allows the guide member 69 to align the orientation of the female screw holder 70 in a fixed direction.

[0046] The female screw holder 70 is provided to face the accommodation hole 522 of the cooling plate 52, and is configured as a square tubular member that covers the side periphery of the female screw member 66 and hooks onto the mounting step 511 of the ceiling member 51. Specifically, the female screw holder 70 includes a holder portion 701 that extends vertically to a length approximately the same as that of the female screw member 66, and an engaging protrusion 702 that protrudes from the underside of the holder portion 701 toward the ceiling member 51.

[0047] A through hole 703 for accommodating the female screw member 66 is formed inside the holder portion 701. The through hole 703 includes an upper hole 703a in which the female screw body 661 is disposed at its upper portion, and a lower hole 703b in which the flange head 662, washer 67, lower sliding seat member 68, and guide member 69 are disposed below the upper hole 703a. The inner diameter of the upper hole 703a is larger than the outer diameter of the female screw body 661 of the female screw member 66, forming a gap C2. The lower hole 703b is D-shaped and accommodates the guide member 69.

[0048] The engaging protrusion 702 protrudes toward the ceiling member 51, and its upper surface comes into contact with the mounting step 511 of the ceiling member 51. The connecting assembly 60 adjusts the axial length of the male screw member 61 and the female screw member 66 by threading them together, so that the engaging protrusion 702 comes into contact with the mounting step 511 and can clamp the ceiling member 51. In other words, the connecting assembly 60 sandwiches the ceiling member 51 and the cooling plate 52 between the locking member 65 connected to the cooling plate 52 and the female screw holder 70 engaged with the ceiling member 51.

[0049] In addition, the protective case 71 extends from the sidewall 10a of the plasma processing chamber 10 to the ceiling member 51 of the shower head 50 to cover the above-mentioned connection assembly 60, thereby preventing the connection assembly 60 from being exposed to the plasma processing space 10s.

[0050] The insulating member 72 is provided between the sidewall 10a of the plasma processing chamber 10 and the shower head 50 (including the connecting assembly 60), thereby insulating the ceiling member 51, which functions as an upper electrode, from the sidewall 10a. This allows the plasma processing apparatus 1 to stably generate plasma in the plasma processing space 10s based on a signal supplied from the power supply 30 to the ceiling member 51.

[0051] [Operation of Plasma Processing Apparatus 1] The plasma processing apparatus 1 according to the embodiment is basically configured as described above, and its operation will be described below.

[0052] As shown in FIG. 1 , the plasma processing apparatus 1 supplies a processing gas to a plasma processing space 10s of a plasma processing chamber 10 via a shower head 50. The plasma processing apparatus 1 also supplies a source RF signal or a bias RF signal from a power supply 30 to the shower head 50 to generate plasma in the plasma processing space 10s. The shower head 50 receives heat from the plasma generated in the plasma processing space 10s. The ceiling member 51 and the cooling plate 52 of the shower head 50 are made of materials with different thermal expansion coefficients. Therefore, a difference in thermal expansion occurs between the ceiling member 51 and the cooling plate 52 due to the plasma heat input.

[0053] If the ceiling member 51 and the cooling plate 52 were fastened together with simple screws (not shown), a difference in their thermal expansion would result in thermal expansion stress being applied to the ceiling member 51, the cooling plate 52, or the screws themselves. If this stress were large, the ceiling member 51 or the cooling plate 52 could be damaged, such as cracked. In contrast, the plasma processing apparatus 1 according to this embodiment uses the connection assembly 60 to connect the ceiling member 51 and the cooling plate 52, as described above.

[0054] Fig. 3(A) is a first enlarged view showing the connection assembly 60 when the cooling plate 52 is not thermally expanded. Fig. 3(B) is a second enlarged view showing the connection assembly 60 when the cooling plate 52 is thermally expanded. Fig. 4 is a third enlarged view showing the connection assembly 60 when the ceiling member 51 is thermally expanded. In Figs. 3 and 4, the middle view shows a cross-sectional view taken along line A-A in the upper view, and the lower view shows a view viewed in the direction of arrow B in the upper view.

[0055] 3A , when no thermal expansion occurs in the shower head 50, the connecting assembly 60 forms a gap C1 between the inner circumferential surface of the accommodation hole 522 of the cooling plate 52 and the male screw member 61, the disc spring 62, and the elastic receiving member 63. This gap C1 allows the connecting assembly 60 to allow relative movement of the male screw member 61, the disc spring 62, the elastic receiving member 63, etc. with respect to the upper sliding seat member 64 (and the locking member 65).

[0056] Similarly, the connecting assembly 60 forms a gap C2 between the female screw member 66, the washer 67, and the lower sliding seat member 68 and the inner circumferential surface of the through-hole 703 of the guide member 69 and the female screw holder 70. The connecting assembly 60 allows the guide member 69 and the female screw holder 70 to move relative to the lower sliding seat member 68 by using this gap C2.

[0057] Even when the gaps C1 and C2 are present, the connecting assembly 60 can firmly clamp the ceiling member 51 and the cooling plate 52 by threading the male screw member 61 and the female screw member 66 together. Specifically, the male screw member 61 received in the receiving hole 522 is hooked onto the cooling plate 52 via the flange 614, the disc spring 62, the elastic receiving member 63, the upper sliding seat member 64, and the locking member 65. As a result, the connecting assembly 60 applies a force that presses the cooling plate 52 downward in the vertical direction. Meanwhile, the female screw member 66 is hooked onto the mounting step 511 of the ceiling member 51 via the flange head 662, the washer 67, the lower sliding seat member 68, the guide member 69, and the female screw holder 70. As a result, the connecting assembly 60 applies a force that presses the ceiling member 51 upward in the vertical direction. Therefore, the connecting assembly 60 can firmly clamp the ceiling member 51 and the cooling plate 52, bringing them into close contact with each other. Even if heat is input to the ceiling member 51 from the plasma processing space 10s during plasma processing, the shower head 50 can smoothly dissipate the heat from the ceiling member 51 to the cooling plate 52.

[0058] 3B, a case where the cooling plate 52 undergoes large thermal expansion relative to the ceiling member 51 will be described. When the cooling plate 52 thermally expands, the protruding outer peripheral portion 521 provided on the radially outer side of the cooling plate 52 also moves (expands) radially outward. As a result, the locking member 65 inserted in the accommodation hole 522 and the upper sliding seat member 64 supported by the locking member 65 also slide horizontally outward (toward the radial direction of the cooling plate 52).

[0059] However, the elastic bearing member 63, which is in contact with the sliding surface 641 of the upper sliding seat member 64 via the sliding surface 631, does not follow the sliding of the upper sliding seat member 64 because the sliding surfaces 631, 641 slide horizontally against each other. This causes the upper sliding seat member 64 to slide relative to the elastic bearing member 63. As a result, the connecting assembly 60 moves the locking member 65 and upper sliding seat member 64 horizontally outward in response to thermal expansion of the cooling plate 52, while maintaining the positions of the elastic bearing member 63, disc spring 62, male screw member 61, etc. Therefore, the inner side of the gap C1 (toward the center of the cooling plate 52) becomes smaller.

[0060] The male screw member 61 is not displaced even by thermal expansion of the cooling plate 52, and can therefore maintain good engagement with the female screw member 66. The connecting assembly 60 can prevent stress from the thermal expansion of the cooling plate 52 from being applied to the fastening structure 73, making it possible to avoid damage to the connecting assembly 60, the ceiling member 51, or the cooling plate 52.

[0061] Next, as shown in Figure 4, a case where the ceiling member 51 thermally expands relative to the cooling plate 52 will be described. For example, when the cooling plate 52 is not exchanging heat or when heat exchange is just starting, the ceiling member 51 may thermally expand. When the ceiling member 51 thermally expands, the mounting step 511 also moves radially outward. As a result, the female screw holder 70 engaged with the mounting step 511 also slides horizontally (radially outward from the ceiling member 51).

[0062] The guide member 69 of the female screw holder 70 moves relative to the lower sliding seat member 68 because the sliding surface 691 is in contact with the sliding surface 681 of the lower sliding seat member 68. In other words, the female screw member 66, the washer 67, and the lower sliding seat member 68 do not follow the sliding of the female screw holder 70 or the guide member 69. As a result, the connecting assembly 60 can accommodate thermal expansion of the ceiling member 51 while reducing the inside of the gap C2 (the side toward the center of the ceiling member 51).

[0063] For example, the female screw member 66 is not displaced even by thermal expansion of the ceiling member 51, and therefore can maintain good engagement with the male screw member 61. The connecting assembly 60 can prevent stress from the thermal expansion of the ceiling member 51 from being applied to the fastening structure 73, and damage to the connecting assembly 60, the ceiling member 51, or the cooling plate 52 can be avoided.

[0064] As described above, the connecting assembly 60 can stably connect components with different thermal expansion coefficients by including the sliding structures 74. Moreover, the connecting assembly 60 is provided with slidable sliding structures 74 at multiple locations (locations corresponding to the male threaded members 61 and locations corresponding to the female threaded members 66), which allows it to appropriately accommodate thermal expansion depending on the location of the component with large thermal expansion. Furthermore, the multiple sliding structures 74 can accommodate thermal expansion even when there is a large difference in thermal expansion.

[0065] Furthermore, the connecting assembly 60 can firmly attach the ceiling member 51 and the cooling plate 52 to each other by adjusting the axial length of the threaded engagement between the male thread member 61 and the female thread member 66. Furthermore, the connecting assembly 60 includes a sliding structure 74 located outside the outer circumferential surface of the fastening structure 73 (the male thread member 61 and the female thread member 66), thereby allowing the sliding structure 74 to slide appropriately while maintaining the threaded engagement of the fastening structure 73. In particular, the sliding structure 74 is disposed adjacent to the female thread member 66, thereby easily absorbing shear forces acting on the female thread member 66 due to thermal expansion. Furthermore, the sliding structure 74 is disposed adjacent to the male thread member 61, thereby easily absorbing shear forces acting on the male thread member 61 due to thermal expansion.

[0066] The sliding structure 74 has two sliding surfaces 631, 641 (or sliding surfaces 681, 691) in contact with each other, and thus can perform sliding in a direction perpendicular to the stacking direction with a simple configuration. Alternatively, when a member having rolling elements that contact the sliding surfaces is used, the sliding structure 74 can perform even smoother sliding.

[0067] The technology of the present disclosure is not limited to the above-described embodiment and may be modified in various ways. For example, the connection assembly 60 according to the embodiment connects the ceiling member 51 and the cooling plate 52 of the shower head 50. However, the connection assembly 60 may connect other members within the plasma processing chamber 10. For example, the other members may include the substrate support 11, a baffle plate attached to the plasma processing chamber 10, a shielding member, and the like. Furthermore, when the plasma processing chamber 10 is assembled from multiple members, the connection assembly 60 may be used as a connecting part connecting the plasma processing chambers 10. Furthermore, the connection assembly 60 may be applied to a substrate processing apparatus that performs heat treatment without performing plasma treatment.

[0068] Furthermore, for example, in the connection assembly 60 according to the embodiment, the male screw member 61 is disposed on the cooling plate 52 side, and the female screw member 66 is disposed on the ceiling member 51 side. However, this arrangement may be reversed.

[0069] Furthermore, the connecting assembly 60 according to the embodiment is configured so that the engaging protrusion 702 of the female screw holder 70 engages with the mounting step 511 of the ceiling member 51. However, if the ceiling member 51 has a hole having a configuration similar to the through-hole 703 described above, the ceiling member 51 can be fastened with the female screw member 66 without using the female screw holder 70. In this case, a washer 67, a lower sliding seat member 68, a guide member 69, etc. may be interposed between the female screw member 66 and the ceiling member 51.

[0070] [Modifications] Next, a connection assembly 60A according to a modification will be described with reference to FIGS. 5 and 6. FIG. 5 is an enlarged cross-sectional view showing the vicinity of the outer periphery of a shower head 50 having a connection assembly 60A according to a modification. FIG. 6A is a first enlarged view showing the connection assembly 60A according to a modification in a state where the cooling plate 52 is not thermally expanded. FIG. 6B is a second enlarged view showing the connection assembly 60A according to a modification in a state where the cooling plate 52 is thermally expanded. Note that the lower views of FIGS. 6A and 6B show views viewed in the direction of arrow B in the upper views.

[0071] The modified connecting assembly 60A differs from the above connecting assembly 60 in that it has a sliding structure 74 adjacent to the female screw member 66 (between the female screw member 66 and the female screw holder 70), but does not have a sliding structure 74 adjacent to the male screw member 61.

[0072] Specifically, the connection assembly 60A includes a male screw member 61, a disc spring 62, an elastic receiving member 63, a locking member 65, a female screw member 66, a washer 67, a lower sliding seat member 68, a guide member 69, and a female screw holder 70. The female screw member 66 is inserted into the elastic receiving member 63 while being threaded onto the male screw member 61 and positioned in the accommodation hole 522.

[0073] The male screw member 61 has a lower threaded portion 611, an intermediate rod portion 612, and a head portion 613. One end of the disc spring 62 contacts the head portion 613, which protrudes radially outward, and is mounted on the outer circumferential surface of the intermediate rod portion 612.

[0074] The elastic receiving member 63 is formed in a cylindrical shape extending along the vertical direction, and is supported at its vertically lower side by a locking member 65 fitted into the accommodation hole 522. The elastic receiving member 63 has a hole portion 63h into which the female screw member 66 can be inserted from its vertically lower side. The outer diameter of the elastic receiving member 63 is approximately the same as the inner diameter of the accommodation hole 522, and no gap C1 (see FIG. 3A) is formed between the elastic receiving member 63 and the cooling plate 52. As a result, when the cooling plate 52 thermally expands, the elastic receiving member 63 and the female screw member 66 also move horizontally in response to the thermal expansion.

[0075] On the other hand, the female screw member 66 has a female screw body 661 and a flange head portion 662, and the upper end of the female screw body 661 is inserted into the elastic receiving member 63 and is housed in the housing hole 522. The washer 67 is supported by the flange head portion 662 of the female screw member 66.

[0076] The lower sliding seat member 68 is formed in an annular shape and has a sliding surface 681 on its upper surface. The guide member 69 has a sliding surface 691 on its lower surface that contacts the lower sliding seat member 68. In other words, the connecting assembly 60A forms one sliding structure 74 by the lower sliding seat member 68 and the guide member 69.

[0077] The guide member 69 is fixed to a female screw holder 70. The female screw holder 70 has a holder portion 701 and an engaging protrusion 702, and the engaging protrusion 702 engages with the mounting step portion 511 of the ceiling member 51. The through hole 703 of the female screw holder 70 has an upper hole 703a and a lower hole 703b, and forms a gap C2 between the female screw member 66 and the through hole 703. The lower hole 703b of the through hole 703 is formed as an elongated hole that allows the flange head 662 of the female screw member 66 to move in one direction.

[0078] The modified connecting assembly 60 is basically formed as described above, and its operation will be described below.

[0079] As shown in FIG. 6A , the connecting assembly 60A firmly clamps the ceiling member 51 and the cooling plate 52 by threading the male screw member 61 and the female screw member 66 together. Specifically, the male screw member 61 engages with the cooling plate 52 via the flange 614, the disc spring 62, the elastic receiving member 63, and the locking member 65, thereby pressing the cooling plate 52 downward in the vertical direction. The female screw member 66 engages with the flange head 662, the washer 67, the lower sliding seat member 68, the guide member 69, and the female screw holder 70 at the protruding outer periphery 521, thereby pressing the ceiling member 51 upward in the vertical direction. Therefore, the connecting assembly 60A can tightly fit the ceiling member 51 and the cooling plate 52 together.

[0080] When no thermal expansion occurs in the shower head 50, the connecting assembly 60A forms a gap C2 between the outer surface of the female screw member 66 (female screw body 661, flange head 662) and the inner surfaces of the through hole 703 of the guide member 69 and the female screw holder 70.

[0081] 6(B), when the cooling plate 52 thermally expands, the protruding outer peripheral portion 521 also moves radially outward, causing the locking member 65 inserted in the accommodation hole 522 and the elastic receiving member 63 supported by the locking member 65 to slide horizontally (radially outward of the cooling plate 52). As a result, the female screw member 66 accommodated in the elastic receiving member 63 also slides horizontally.

[0082] Furthermore, the horizontal sliding of the female thread member 66 also causes the washer 67 and the lower sliding seat member 68 to slide. Meanwhile, the guide member 69, which is in contact with the sliding surface 681 of the lower sliding seat member 68 via the sliding surface 691, does not follow the sliding of the lower sliding seat member 68. This causes the lower sliding seat member 68 to move relative to the guide member 69. As a result, the connecting assembly 60A can accommodate the thermal expansion of the cooling plate 52 while reducing the outer side of the gap C2 (the side away from the cooling plate 52).

[0083] For example, the female screw member 66 can be maintained in a state where it is not displaced even due to thermal expansion of the cooling plate 52. Therefore, the stress caused by the thermal expansion of the cooling plate 52 is prevented from being applied to the fastening structure 73, and damage to the connecting assembly 60A, the ceiling member 51, or the cooling plate 52 can be avoided.

[0084] As described above, the modified connecting assembly 60A can also effectively connect two components with different thermal expansion coefficients and can accommodate differences in thermal expansion among multiple components. In particular, by including a single sliding structure 74, the connecting assembly 60A can further simplify its structure and reduce manufacturing costs.

[0085] The above-disclosed embodiments include, for example, the following aspects.

[0086] [Supplementary Note 1] A substrate processing apparatus for processing substrates, comprising: a first member and a second member stacked on top of each other and having different thermal expansion coefficients; and a coupling assembly extending parallel to a stacking direction of the first member and the second member and coupling the first member and the second member, wherein the coupling assembly has a sliding structure that is slidable in a direction perpendicular to the stacking direction upon thermal expansion of the first member and / or the second member. [Supplementary Note 2] The substrate processing apparatus according to Supplementary Note 1, wherein the coupling assembly has a male screw member and a female screw member that extend in the stacking direction and threadably engage with each other, and wherein the clamping force applied to the first member and the second member is adjusted by adjusting the axial length of the threaded engagement of the male screw member and the female screw member. [Supplementary Note 3] The substrate processing apparatus according to Supplementary Note 2, wherein the sliding structure is provided outside the outer peripheral surfaces of the male screw member and the female screw member. [Supplementary Note 4] The substrate processing apparatus according to Supplementary Note 2 or 3, wherein the sliding structure is disposed adjacent to the female screw member. [Supplementary Note 5] The substrate processing apparatus according to any one of Supplements 2 to 4, wherein the sliding structure is disposed adjacent to the male screw member exposed from the female screw member. [Supplementary Note 6] The substrate processing apparatus according to any one of Supplements 1 to 5, wherein the connection assembly has a plurality of the sliding structures along the stacking direction. [Supplementary Note 7] The substrate processing apparatus according to any one of Supplements 1 to 6, wherein the sliding structure brings two members, each having a sliding surface extending in a direction perpendicular to the stacking direction, into contact with the sliding surfaces. [Supplementary Note 8] The substrate processing apparatus according to any one of Supplements 1 to 7, wherein the sliding structure brings a member, having a sliding surface extending in a direction perpendicular to the stacking direction, into contact with a member having a rolling element contacting the sliding surface. [Supplementary Note 9] The substrate processing apparatus according to any one of Supplements 1 to 8, wherein the first member and the second member are provided in a plasma processing chamber having a plasma processing space therein for generating plasma.[Supplementary Note 10] The substrate processing apparatus according to Supplementary Note 9, wherein the first member and the second member constitute a showerhead that discharges a processing gas inside the plasma processing chamber and is supplied with power for generating the plasma. [Supplementary Note 11] The substrate processing apparatus according to Supplementary Note 10, wherein the first member is a ceiling member having a plurality of gas inlets for introducing the processing gas into the plasma processing space, and the second member is a cooling plate that is provided vertically above the first member and dissipates heat from the ceiling member. [Supplementary Note 12] A connection assembly that connects a first member and a second member provided in a substrate processing apparatus for processing substrates, wherein the first member and the second member are stacked on top of each other and have different thermal expansion coefficients, and the connection assembly has a sliding structure that extends parallel to a stacking direction of the first member and the second member and is slidable in a direction perpendicular to the stacking direction upon thermal expansion of the first member and / or the second member.

[0087] The substrate processing apparatus and connection assembly 60, 60A according to the presently disclosed embodiments are illustrative in all respects and not restrictive. Various modifications and improvements can be made to the embodiments without departing from the spirit and scope of the appended claims. The features described in the above embodiments can be configured in other ways and can be combined within the scope of the appended claims.

[0088] The substrate processing apparatus of the present disclosure can be applied to any type of apparatus, including atomic layer deposition (ALD) apparatus, capacitively coupled plasma (CCP), inductively coupled plasma (ICP), radial line slot antenna (RLSA), electron cyclotron resonance plasma (ECR), and helicon wave plasma (HWP).

[0089] This application claims priority from Japanese Patent Application No. 2023-204089, filed on December 1, 2023, with the Japan Patent Office, the entire contents of which are incorporated herein by reference.

[0090] 1 Plasma processing apparatus 51 Ceiling member 52 Cooling plate 60, 60A Connection assembly 74 Sliding structure W Substrate

Claims

1. A substrate processing apparatus for processing substrates, comprising: a first member and a second member that are stacked on top of each other and have different thermal expansion coefficients; and a connecting assembly that extends parallel to the stacking direction of the first member and the second member and connects the first member and the second member, wherein the connecting assembly has a sliding structure that is slidable in a direction perpendicular to the stacking direction upon thermal expansion of the first member and / or the second member.

2. The substrate processing apparatus of claim 1, wherein the connecting assembly has a male screw member and a female screw member that extend in the stacking direction and screw into each other, and the clamping force applied to the first member and the second member is adjusted by adjusting the axial length of the screwed engagement between the male screw member and the female screw member.

3. The substrate processing apparatus according to claim 2, wherein the sliding structure is provided outside the outer circumferential surfaces of the male screw member and the female screw member.

4. The substrate processing apparatus according to claim 2, wherein the sliding structure is disposed adjacent to the female screw member.

5. The substrate processing apparatus according to claim 2, wherein the sliding structure is disposed adjacent to the male screw member exposed from the female screw member.

6. The substrate processing apparatus according to claim 1, wherein the connecting assembly has a plurality of the sliding structures along the stacking direction.

7. A substrate processing apparatus according to any one of claims 1 to 5, wherein the sliding structure brings the sliding surfaces of two members, each having a sliding surface extending in a direction perpendicular to the stacking direction, into contact with each other.

8. A substrate processing apparatus according to any one of claims 1 to 5, wherein the sliding structure brings into contact a member having a sliding surface extending in a direction perpendicular to the stacking direction and a member having a rolling body that contacts the sliding surface.

9. The substrate processing apparatus according to claim 1, wherein the first member and the second member are provided in a plasma processing chamber having a plasma processing space therein for generating plasma.

10. The substrate processing apparatus according to claim 9, wherein the first member and the second member form a showerhead that discharges a processing gas inside the plasma processing chamber and receives power for generating the plasma.

11. The substrate processing apparatus of claim 10, wherein the first member is a ceiling member having a plurality of gas inlets for introducing the processing gas into the plasma processing space, and the second member is a cooling plate disposed vertically above the first member and dissipating heat from the ceiling member.

12. A connecting assembly for connecting a first member and a second member provided in a substrate processing apparatus for processing substrates, the first member and the second member being stacked on top of each other and having different thermal expansion coefficients, the connecting assembly having a sliding structure extending parallel to a stacking direction of the first member and the second member and being slidable in a direction perpendicular to the stacking direction upon thermal expansion of the first member and / or the second member.

Images