Structure for use in plasma processing apparatus

Abstract

This structure for use in a plasma processing apparatus comprises a first member, a second member, a plurality of support members, a plurality of adjustment members, and a tubular member. The first member has a first surface. The second member has a second surface facing the first surface. The plurality of support members and the plurality of adjustment members are provided between the first surface and the second surface. The tubular member penetrates a space between the first surface and the second surface. The plurality of support members are disposed at different densities in a first space which is below a first unit region on the first surface and has no tubular member disposed therein, and in a second space which is below a second unit region on the first surface, has the tubular member disposed therein, and has the same volume as the first space. The plurality of adjustment members are disposed at different densities in the first space and the second space.

Description

Structures used in plasma processing equipment

[0001] Various aspects and embodiments of the present disclosure relate to structures for use in plasma processing apparatuses.

[0002] Patent Document 1 listed below discloses that "the flow path 123 is formed in the base 122 and opens to the electrostatic chuck 111 side at the upper surface 122c of the base 122. In other words, the flow path 123 is formed in a spiral shape in the base 122 and has an opening 123a that opens in a spiral shape on the upper surface. This makes it possible to control the temperature of the substrate W over the entire area of ​​the substrate support surface 111a of the substrate support part 11 (see Figure 1)."

[0003] Japanese Patent Application Laid-Open No. 2023-3003

[0004] The present disclosure provides a structure used in a plasma processing apparatus that can suppress environmental imbalances within a chamber when processing a substrate.

[0005] One aspect of the present disclosure provides a structure for use in a plasma processing apparatus, comprising a first member, a second member, a plurality of support members, a plurality of adjustment members, and a cylindrical member. The first member has a first surface. The second member has a second surface opposite the first surface. The plurality of support members are provided between the first surface and the second surface. The plurality of adjustment members are provided between the first surface and the second surface. The cylindrical member penetrates a space between the first surface and the second surface. The plurality of support members are arranged at different densities in a first space below a first unit area on the first surface, where no cylindrical member is arranged, and in a second space below a second unit area on the first surface, where a cylindrical member is arranged and has the same volume as the first space. The plurality of adjustment members are arranged at different densities in the first space and the second space.

[0006] According to various aspects and embodiments of the present disclosure, it is possible to suppress the imbalance of the environment in the chamber when processing a substrate.

[0007] FIG. 1 is a diagram illustrating an example of the configuration of a plasma processing system. FIG. 2 is a diagram illustrating an example of the configuration of a capacitively coupled plasma processing apparatus. FIG. 3 is a cross-sectional view showing an example of the structure of a base. FIG. 4 is a diagram illustrating an example of the A-A cross section of the base illustrated in FIG. 3. FIG. 5 is a diagram illustrating another example of the A-A cross section of the base illustrated in FIG. 3. FIG. 6 is a cross-sectional view showing an example of a housing. FIG. 7 is a diagram illustrating an example of the B-B cross section of the housing illustrated in FIG. 6.

[0008] Hereinafter, embodiments of the structure used in the disclosed plasma processing apparatus will be described in detail with reference to the drawings. Note that the structure used in the disclosed plasma processing apparatus is not limited to the following embodiments.

[0009] Incidentally, a base that cools a substrate with a coolant flowing through it has through-holes for passing lift pins, electrical wiring, etc. When a spiral flow path is provided in the base, the flow path is formed to bypass the through-holes. This causes the temperature near the through-holes to be higher than in other areas, reducing the uniformity of the temperature distribution in the base and the substrate.

[0010] Furthermore, dielectrics are sometimes used as insulating members in plasma processing apparatuses for processing substrates, but their resistance is high but finite. Therefore, when AC power is supplied, a small amount of induced current flows, resulting in power loss. This power loss increases as the volume of the dielectric increases. Furthermore, when the power loss is large, the difference in power loss between apparatuses also increases. Therefore, it is conceivable to reduce the volume of the insulating member and thereby reduce power loss by making the insulating member hollow.

[0011] However, in the portion of the plasma processing apparatus where the insulating member is provided, a flow path for flowing gas or a through hole for passing electrical wiring may be formed. The portion where such a flow path or through hole is formed has a larger dielectric volume than the other portion, and the power loss in the portion where such a flow path or through hole is formed may be larger than the other portion. This may cause a bias in the power loss within the chamber, resulting in a bias in the distribution of plasma. The bias in the distribution of plasma reduces the uniformity of substrate processing.

[0012] Therefore, the present disclosure provides a technique that can suppress the imbalance in the environment inside a chamber when processing a substrate.

[0013] [Configuration Example of a Plasma Processing System] FIG. 1 is a diagram illustrating a configuration example of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing apparatus 1 is an example of a substrate processing apparatus. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0014] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), or surface wave plasma (SWP). Various types of plasma generating units may be used, including alternating current (AC) plasma generating units and direct current (DC) plasma generating units. In one embodiment, the AC signal (AC power) used in the AC plasma generating unit has a frequency in the range of 100 kHz to 10 GHz. Therefore, AC signals include radio frequency (RF) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0015] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform various processes described herein. In one embodiment, part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 may be implemented by, for example, a computer 2a. The processing unit 2a1 may be configured to read a program from the storage unit 2a2 and execute the read program to perform various control operations. The program may be stored in the storage unit 2a2 in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 by the processing unit 2a1 for execution. The medium may be various storage media readable by the computer 2a or a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). 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 local area network (LAN).

[0016] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 2 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

[0017] The capacitively coupled 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 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 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0018] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region 111a for supporting a substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. 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. Therefore, the central region 111a is also called a substrate support surface for supporting the substrate W, and the annular region 111b is also called a ring support surface for supporting the ring assembly 112.

[0019] In one embodiment, the main body 111 includes a base 50 and an electrostatic chuck 1111. The base 50 includes a conductive member. The conductive member of the base 50 can function as a lower electrode. The electrostatic chuck 1111 is disposed on the base 50. The base 50 is provided at the bottom of the plasma processing chamber 10 and is supported by a housing 60 made of a dielectric material. The base 50 and the housing 60 are an example of a structure used in the plasma processing apparatus 1. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Note that the annular region 111b may also be provided by another member surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. At least one RF / DC electrode coupled to an RF power supply 31 and / or a DC power supply 32 (described later) may be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal (described later) is supplied to the at least one RF / DC electrode, the RF / DC electrode is also referred to as a bias electrode. Note that the conductive member of the base 50 and the at least one RF / DC electrode may function as multiple lower electrodes. Alternatively, the electrostatic electrode 1111b may function as the lower electrode. Therefore, the substrate support 11 includes at least one lower electrode.

[0020] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

[0021] The substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path 50b, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path 50b. In this embodiment, the heat transfer fluid is a refrigerant. A chiller unit 50a is connected to the flow path 50b of the base 50 via a pipe 50c. The refrigerant, whose temperature is controlled by the chiller unit 50a, is supplied to the flow path 50b of the base 50 via the pipe 50c, and the refrigerant that has flowed through the flow path 50b is returned to the chiller unit 50a via the pipe 50c.

[0022] In one embodiment, the flow passage 50b is formed in the base 50, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. The substrate support 11 may also include a heat transfer gas supply configured to supply a heat transfer gas to a gap between the back surface of the substrate W and the central region 111a.

[0023] 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 at least one 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.

[0024] 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 at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

[0025] 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) to at least one lower electrode and / or at least one upper electrode. This generates a plasma from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of the plasma generation unit 12. Furthermore, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0026] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to at least one lower electrode and / or at least one upper electrode 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 10 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0027] The second RF generator 31b is coupled to at least one lower electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0028] 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 the at least one lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to the at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

[0029] In various embodiments, the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating the sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have either positive or negative polarity. Furthermore, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses within one period. 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.

[0030] 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.

[0031] [Structure of Base 50] Fig. 3 is a cross-sectional view showing an example of the structure of the base 50, and Fig. 4 is a view showing an example of the A-A cross section of the base 50 illustrated in Fig. 3. The base 50 includes an outer wall portion 500 and an intermediate member 501. A plurality of support members 502 and a plurality of adjustment members 503 are provided in the space between an upper surface 501a of the intermediate member 501 and a lower surface 500a of the outer wall portion 500 facing the upper surface 501a. In the example of Fig. 4, in order to easily distinguish between the support members 502 and the adjustment members 503, the support members 502 are indicated by white circles and the adjustment members 503 are indicated by black circles.

[0032] One end of each of the support members 502 and each of the adjustment members 503 is connected to the lower surface 500a of the outer wall portion 500, and the other end is connected to the upper surface 501a of the intermediate member 501. The outer wall portion 500 is an example of a first member, the intermediate member 501 is an example of a second member, the lower surface 500a of the outer wall portion 500 is an example of a first surface, and the upper surface 501a of the intermediate member 501 is an example of a second surface.

[0033] The flow path 50b of the base 50 is a space between the outer wall portion 500 and the intermediate member 501. The refrigerant supplied from the chiller unit 50a flows through the flow path 50b via an opening 51 formed approximately in the center of the intermediate member 501. The refrigerant that has flowed through the flow path 50b is returned to the chiller unit 50a via a gap 52 between the periphery of the intermediate member 501 and the side wall of the outer wall portion 500 and a pipe 50c. This makes it possible to suppress the temperature gradient of the refrigerant flowing through the base 50. As the refrigerant flows through the flow path 50b of the base 50, heat exchange occurs between the refrigerant and the outer wall portion 500, the intermediate member 501, the support member 502, and the adjustment member 503.

[0034] The base 50 is also provided with a pipe 504 that penetrates the outer wall portion 500 and the intermediate member 501. Components such as lift pins and electrical wiring are arranged inside the pipe 504, and a heat transfer gas or the like flows through the pipe 504. In the examples of FIGS. 3 and 4 , the base 50 is provided with one pipe 504, but the disclosed technology is not limited to this, and the base 50 may be provided with multiple pipes 504. In this embodiment, the outer wall portion 500, the intermediate member 501, the support member 502, the adjustment member 503, and the pipe 504 are integrally formed from, for example, metal, ceramics, MMC (Metal Matrix Composites), or the like.

[0035] 4, region R1 represents a first unit area on the upper surface 501a of the intermediate part 501 where the pipes 504 are not arranged. Region R2 represents a second unit area on the upper surface 501a of the intermediate part 501 where the pipes 504 are arranged and has the same area as the first unit area. Also, in FIG. 3, space SP1 represents a first space above the first unit area, and space SP2 represents a second space above the second unit area. Space SP1 and space SP2 have the same volume.

[0036] In this embodiment, the multiple support members 502 are arranged at different densities in the space SP1 and the space SP2. For example, as shown in Figure 4, 12 support members 502 are arranged in the region R1 corresponding to the space SP1, and 6 support members 502 are arranged in the region R2 corresponding to the space SP2. Because the spaces SP1 and SP2 have the same volume, the multiple support members 502 are arranged more densely in the space SP1 than in the space SP2. Adjacent support members 502 are arranged at intervals of, for example, 1 mm to 5 mm.

[0037] In this embodiment, the plurality of adjustment members 503 are arranged at different densities in the space SP1 and the space SP2. For example, as shown in Fig. 4, no adjustment members 503 are arranged in the region R1 corresponding to the space SP1, but 14 adjustment members 503 are arranged in the region R2 corresponding to the space SP2. Because the spaces SP1 and SP2 have the same volume, the plurality of adjustment members 503 are arranged more densely in the space SP2 than in the space SP1.

[0038] In the example of Figure 4, adjustment members 503 are not arranged in region R1 corresponding to space SP1, but adjustment members 503 may be arranged in region R1 as long as they are arranged at a lower density than in region R1 corresponding to space SP2.

[0039] Here, since the pipes 504 are arranged in the region R2, the number of support members 502 arranged in the space SP2 is small. Therefore, the amount of heat transferred between the refrigerant and the base 50 in the space SP2 is smaller than the amount of heat transferred between the refrigerant and the base 50 in the space SP1. Therefore, the temperature of the region on the top surface of the base 50 corresponding to the space SP1 may differ from the temperature of the region on the top surface of the base 50 corresponding to the space SP2.

[0040] Therefore, in this embodiment, the density of the adjusting member 503 in the space SP1 and the density of the adjusting member 503 in the space SP2 are adjusted to reduce the difference in the amount of heat transferred between the refrigerant and the base 50 in the space SP1 and the space SP2. This reduces the difference in temperature between the region on the top surface of the base 50 corresponding to the space SP1 and the region on the top surface of the base 50 corresponding to the space SP2, thereby improving the uniformity of the temperature distribution on the top surface of the base 50.

[0041] In this embodiment, the density of the adjusting members 503 in the space SP1 and the density of the adjusting members 503 in the space SP2 are adjusted, for example, as follows.

[0042] The amount of heat Q exchanged between the refrigerant flowing through the flow path 50b of the base 50 and the base 50 is expressed, for example, by the following equation (1). In the above formula (1), A represents the solid-liquid interface surface area, h represents the heat transfer coefficient, and T Liq represents the temperature of the refrigerant, and T Top represents the target surface temperature of the base 50.

[0043] In the above formula (1), the heat transfer coefficient h is the same value throughout the entire base 50, and the temperature T Liq It is assumed that the surface area A of the solid-liquid interface can be made the same at all points on the base 50. In this case, if the surface area A of the solid-liquid interface can be made the same at all points on the base 50, the surface temperature T Top Therefore, in this embodiment, the adjustment member 503 is devised to be disposed in such a way that the difference in the solid-liquid interface surface area A at each position on the base 50 is reduced.

[0044] For example, in FIG. 3, if the solid-liquid interface surface area in the space SP1 is S1 and the solid-liquid interface surface area in the space SP2 is S2, the adjusting member 503 is arranged so as to satisfy the following formula (2).

[0045] In the above formula (2), the solid-liquid interface surface area S1 includes, within the space SP1, the area of ​​the lower surface 500a of the outer wall portion 500, the area of ​​the side surfaces of the support member 502, and the area of ​​the upper surface 501a of the intermediate member 501. Furthermore, the solid-liquid interface surface area S2 includes, within the space SP2, the area of ​​the lower surface 500a of the outer wall portion 500, the area of ​​the side surfaces of the support member 502, the area of ​​the upper surface 501a of the intermediate member 501, the area of ​​the side surfaces of the adjustment member 503, and the area of ​​the side surfaces of the piping 504.

[0046] Moreover, the area A2 of the region R2 in FIG. 4 is expressed, for example, by the following formula (3).

[0047] In the above formula (3), A3 represents the area of ​​the region on the upper surface 501a of the intermediate member 501 where the piping 504 is arranged, and A4 represents the area of ​​the region R2 on the upper surface 501a of the intermediate member 501 where the piping 504 is not arranged.

[0048] The solid-liquid interface surface area S2 in the space SP2 is expressed, for example, by the following formula (4).

[0049] In the above formula (4), S3 represents the area of ​​the side surface of the pipe 504 exposed in the space through which the refrigerant passes, and S4 represents the area of ​​the side surface of the adjustment member 503.

[0050] The areas A4 and S4 that satisfy the above (2) to (4) are determined, and the density of the adjusting members 503 in the space SP1 and the density of the adjusting members 503 in the space SP2 are adjusted so as to satisfy the determined areas A4 and S4. The base 50 that realizes the adjusted density of the adjusting members 503 can be created using, for example, a 3D printer.

[0051] 3 and 4, the refrigerant is supplied into the flow path 50b through the opening 51 located substantially in the center of the intermediate member 501, but the disclosed technology is not limited to this. As another example, as shown in FIG. 5, the refrigerant supplied from the chiller unit 50a may be supplied into the flow path 50b through the opening 53, and the refrigerant in the flow path 50b may be returned to the chiller unit 50a through the opening 54.

[0052] In the example of Fig. 5, a plurality of partition walls 55 that rectify the flow of the refrigerant are provided in the flow path 50b, and a flow of the refrigerant indicated by the dotted arrows in Fig. 5 occurs in the flow path 50b. The partition walls 55 may be formed integrally with the base 50 using the same material as the base 50. In the example of Fig. 5, the thickness of the partition walls 55 is, for example, 5 mm or less.

[0053] 5 , as the refrigerant flows from upstream to downstream, the temperature of the refrigerant increases due to heat exchange with the base 50, and therefore the temperature difference between the refrigerant on the downstream side and the base 50 becomes smaller than the temperature difference between the refrigerant on the upstream side and the base 50. Therefore, if the density of the adjustment member 503 is the same on the upstream and downstream sides of the refrigerant, the amount of heat transferred by heat exchange with the refrigerant on the downstream side will be less than the amount of heat transferred by heat exchange with the refrigerant on the upstream side. This creates a temperature difference in the upper surface of the base 50 between the upstream and downstream sides of the refrigerant.

[0054] 5, the adjustment members 503 are arranged at different densities on the upstream and downstream sides of the refrigerant in the flow path 50b. Specifically, as shown in FIG. 5, more adjustment members 503 are arranged in region R4 downstream of the refrigerant than in region R3 upstream of the refrigerant. In the example of FIG. 5, the space in the flow path 50b corresponding to region R3 and the space in the flow path 50b corresponding to region R4 have the same volume.

[0055] In the example of Figure 5, the adjustment member 503 is not arranged in the space of the flow path 50b corresponding to region R3, but the adjustment member 503 may also be arranged in the space of the flow path 50b corresponding to region R3 as long as the density is lower than that in the space of the flow path 50b corresponding to region R4.

[0056] [Structure of Housing 60] Fig. 6 is a cross-sectional view showing an example of the structure of the housing 60, and Fig. 7 is a view showing an example of the B-B cross-section of the housing 60 illustrated in Fig. 6. The housing 60 includes a hollow outer wall portion 600. The outer wall portion 600 has an upper portion 601 and a lower portion 602. A plurality of support members 603 and a plurality of adjustment members 604 are provided in the space between an upper surface 602a of the lower portion 602 and a lower surface 601a of the upper portion 601 opposite the upper surface 602a. In the example of Fig. 7, in order to easily distinguish between the support members 603 and the adjustment members 604, the support members 603 are indicated by white circles and the adjustment members 604 are indicated by black circles.

[0057] One end of each support member 603 and each adjustment member 604 is connected to the lower surface 601a of the upper portion 601, and the other end is connected to the upper surface 602a of the lower portion 602. The upper portion 601 of the outer wall portion 600 is an example of a first member, the lower portion 602 of the outer wall portion 600 is an example of a second member, the lower surface 601a of the upper portion 601 is an example of a first surface, and the upper surface 602a of the lower portion 602 is an example of a second surface. Adjacent support members 603 are arranged at intervals of 1 mm to 5 mm, for example.

[0058] The housing 60 is also provided with a pipe 605 that penetrates the outer wall portion 600. Components such as lift pins and electrical wiring are arranged within the adjustment member 604, and a heat transfer gas or the like flows through the adjustment member 604. In the examples of FIGS. 6 and 7 , the housing 60 is provided with one pipe 605, but the disclosed technology is not limited to this, and the housing 60 may be provided with multiple pipes 605. In this embodiment, the outer wall portion 600, the support member 603, the adjustment member 604, and the pipe 605 are integrally formed of, for example, a dielectric material.

[0059] 7, region R5 represents a first unit area on the upper surface 602a of the lower portion 602 where the pipe 605 is not arranged. Region R6 represents a second unit area on the upper surface 602a of the lower portion 602 where the pipe 605 is arranged and has the same area as the first unit area. Also, in FIG. 6, space SP5 represents a first space above the first unit area, and space SP6 represents a second space above the second unit area. Space SP5 and space SP6 have the same volume.

[0060] In this embodiment, the plurality of support members 603 are arranged at different densities in the space SP5 and the space SP6. For example, as shown in Fig. 7, nine support members 603 are arranged in the region R5 corresponding to the space SP5, and eight support members 602 are arranged in the region R6 corresponding to the space SP6. Because the spaces SP5 and SP6 have the same volume, the plurality of support members 603 are arranged more densely in the space SP5 than in the space SP6.

[0061] In this embodiment, the plurality of adjustment members 604 are arranged at different densities in the space SP5 and the space SP6. For example, as shown in Fig. 7, four adjustment members 604 are arranged in the region R5 corresponding to the space SP5, but no adjustment members 603 are arranged in the region R6 corresponding to the space SP6. Because the spaces SP5 and SP6 have the same volume, the plurality of adjustment members 604 are arranged more densely in the space SP5 than in the space SP6.

[0062] In the example of Figure 7, adjustment members 604 are not arranged in region R6 corresponding to space SP6, but adjustment members 604 may be arranged in region R6 as long as they are arranged at a lower density than in region R5 corresponding to space SP5.

[0063] Here, it is conceivable to make the housing 60 hollow in order to reduce power loss in the housing 60. However, if the piping 605 is present in the housing 60, the dielectric material constituting the piping 605 will cause greater power loss near the piping 605 than in other parts of the housing 60. This may result in a bias in the distribution of power loss within the plasma processing chamber 10, which in turn may cause a bias in the distribution of plasma. If the plasma distribution becomes biased, the uniformity of processing of the substrate W using plasma will decrease.

[0064] Therefore, in this embodiment, the density of the adjusting members 604 in the space SP5 and the density of the adjusting members 604 in the space SP6 are adjusted to reduce the difference in power loss between the space SP5 and the space SP6, thereby suppressing bias in the distribution of power loss in the plasma processing chamber 10, improving the uniformity of the plasma distribution, and improving the uniformity in processing the substrate W using plasma.

[0065] In this embodiment, the density of the adjusting members 604 in the space SP5 and the density of the adjusting members 604 in the space SP6 are adjusted, for example, as follows.

[0066] For example, in FIG. 6, if the volume of the dielectric in the space SP5 is V1 and the volume of the dielectric in the space SP6 is V2, the adjusting member 503 is arranged so as to satisfy the following formula (5).

[0067] Moreover, the area A2 of the region R6 in FIG. 7 is expressed, for example, by the following formula (6).

[0068] In the above formula (6), A3 represents the area of ​​the region where the pipe 605 is arranged, and A4 represents the area of ​​the region R6 where the pipe 605 is not arranged.

[0069] The volume V2 of the dielectric material in the space SP6 is expressed, for example, by the following equation (7).

[0070] In the above formula (7), V3 represents the volume of the pipe 605 in the space SP6, and V4 represents the volume of the portion other than the pipe 605 in the space SP6.

[0071] The volumes V1 and V2 that satisfy the above (5) to (7) are determined, and the density of the adjusting member 604 in the space SP5 and the density of the adjusting member 604 in the space SP6 are adjusted so as to satisfy the determined volumes V1 and V2. The housing 60 that realizes the adjusted density of the adjusting member 604 can be created using, for example, a 3D printer.

[0072] The embodiment has been described above. As described above, the structure (base 50, housing 60) used in the plasma processing apparatus of this embodiment includes a first member (outer wall portion 500, upper portion 601), a second member (intermediate member 501, lower portion 602), a plurality of support members (support members 502, support members 603), a plurality of adjustment members (adjustment members 503, adjustment members 604), and a cylindrical member (piping 504, piping 605). The first member has a first surface (lower surface 500a, lower surface 601a). The second member has a second surface (lower surface 500a, lower surface 601a) opposite the first surface. The plurality of support members are provided between the first surface and the second surface. The plurality of adjustment members are provided between the first surface and the second surface. The cylindrical member penetrates the space between the first surface and the second surface. The plurality of support members are arranged at different densities in a first space (space SP1, space SP5) below a first unit region (region R1, region R5) on the first surface, in which no cylindrical member is arranged, and in a second space (space SP2, space SP6) below a second unit region (region R2, region R6) on the first surface, in which a cylindrical member is arranged and which has the same volume as the first space. The plurality of adjustment members are arranged at different densities in the first space and the second space. This can suppress imbalance in the environment within the plasma processing chamber 10 when processing a substrate W.

[0073] In the above-described embodiment, the first member (outer wall portion 500), the second member (intermediate member 501), the support member (support member 502), the adjustment member (adjustment member 503), and the cylindrical member (pipe 504) are made of metal, ceramics, or MMC (Metal Matrix Composites). This can improve the uniformity of the temperature distribution on the upper surface of the base 50.

[0074] In the above-described embodiment, the support members are arranged more densely in the first space than in the second space, and the adjustment members are arranged more densely in the second space than in the first space, thereby improving the uniformity of the temperature distribution on the upper surface of the base 50.

[0075] In the above-described embodiment, the structure is a base through which a heat transfer fluid flows in the space between the first surface and the second surface, and the adjusting member is in contact with the heat transfer fluid, thereby improving the uniformity of the temperature distribution on the upper surface of the base 50.

[0076] In the above-described embodiment, a partition (partition 55) for rectifying the flow of the heat transfer fluid is provided in the space between the first surface and the second surface, and the adjusting members are arranged more densely downstream of the heat transfer fluid than upstream. The thickness of the partition is, for example, 5 mm or less. This can improve the uniformity of the temperature distribution on the upper surface of the base 50.

[0077] In the above embodiment, the heat transfer fluid is supplied from the center of the second surface into the space between the first and second surfaces and is discharged from the periphery of the second surface, thereby improving the uniformity of the temperature distribution on the upper surface of the base 50.

[0078] In the above-described embodiment, the first member (upper portion 601), the second member (lower portion 602), the support member (support member 603), the adjustment member (adjustment member 604), and the cylindrical member (piping 605) are made of a dielectric material, which can suppress uneven distribution of power loss within the plasma processing chamber 10.

[0079] In the above embodiment, the support members and the adjustment members are arranged more densely in the first space (SP6) than in the second space (SP5), thereby preventing uneven distribution of power loss within the plasma processing chamber 10.

[0080] In the above-described embodiment, the structure is a housing that supports the base, which can suppress uneven distribution of power loss within the plasma processing chamber 10.

[0081] [Others] The technology disclosed in the present application is not limited to the above-described embodiment, and various modifications are possible within the scope of the gist thereof.

[0082] For example, in the above-described embodiment, the cross-sectional shapes of the support member 502, the adjustment member 503, the support member 603, and the adjustment member 604 are circular as shown in Figures 4, 5, and 7, but the disclosed technology is not limited to this. As another example, the cross-sectional shape of at least one of the support member 502, the adjustment member 503, the support member 603, and the adjustment member 604 may be a polygonal shape such as a triangle or a rectangle, an ellipse, an oval, an arc, or a combination of these.

[0083] In the above-described embodiment, the support member 502, the adjustment member 503, the support member 603, and the adjustment member 604 are each columnar, as shown in Fig. 3 and Fig. 6, but the disclosed technology is not limited to this. As another example, at least one of the support member 502, the adjustment member 503, the support member 603, and the adjustment member 604 may be shaped like a grid or lattice.

[0084] In the above embodiment, a refrigerant flows as a heat transfer fluid through the flow path 50b of the base 50, but the disclosed technology is not limited to this. As another example, a heat medium may flow as a heat transfer fluid through the flow path 50b of the base 50.

[0085] In the above-described embodiment, a capacitively coupled plasma (CCP) is used as an example of the plasma source, but the disclosed technology is not limited to this. For example, other plasma sources such as microwave plasma and inductively coupled plasma (ICP) may be used as the plasma source.

[0086] It should be noted that the disclosed embodiments are illustrative in all respects and should not be considered limiting. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims.

[0087] Furthermore, the following supplementary notes are disclosed regarding the above-described embodiment.

[0088] (Supplementary Note 1) A structure used in a plasma processing apparatus, comprising: a first member having a first surface; a second member having a second surface opposite the first surface; a plurality of support members provided between the first surface and the second surface; a plurality of adjustment members provided between the first surface and the second surface; and a cylindrical member passing through a space between the first surface and the second surface, wherein the plurality of support members are arranged at different densities in a first space below a first unit area on the first surface, in which the cylindrical member is not arranged, and in a second space below a second unit area on the first surface, in which the cylindrical member is arranged and which has the same volume as the first space, and the plurality of adjustment members are arranged at different densities in the first space and the second space. (Supplementary Note 2) The structure according to Supplementary Note 1, wherein the first member, the second member, the support member, the adjustment member, and the cylindrical member are made of metal, ceramics, or MMC (Metal Matrix Composites). (Supplementary Note 3) The structure according to Supplementary Note 1 or 2, wherein the plurality of support members are arranged more densely in the first space than in the second space, and the plurality of adjustment members are arranged more densely in the second space than in the first space. (Supplementary Note 4) The structure according to any one of Supplements 1 to 3, wherein the structure is a base through which a heat transfer fluid flows in a space between the first surface and the second surface, and the adjustment member contacts the heat transfer fluid. (Supplementary Note 5) The structure according to Supplementary Note 4, wherein a partition wall that rectifies the heat transfer fluid is provided in the space between the first surface and the second surface, and the adjustment members are arranged more densely downstream of the heat transfer fluid than upstream. (Supplementary Note 6) The structure according to Supplementary Note 5, wherein the thickness of the partition wall is 5 mm or less. (Supplementary Note 7) The structure according to Supplementary Note 4, wherein the heat transfer fluid is supplied from the center of the second surface into the space between the first surface and the second surface and discharged from the periphery of the second surface. (Supplementary Note 8) The structure according to Supplementary Note 1, wherein the first member, the second member, the support member, the adjustment member, and the tubular member are made of a dielectric.(Supplementary Note 9) The structure according to Supplementary Note 1 or 8, wherein the plurality of support members and the plurality of adjustment members are arranged more densely in the first space than in the second space. (Supplementary Note 10) The structure according to any one of Supplementary Notes 1, 8, and 9, wherein the structure is a housing that supports a base.

[0089] R Region SP Space W Substrate 1 Plasma processing apparatus 10 Plasma processing chamber 10s Plasma processing space 11 Substrate support 111 Main body 111a Central region 111b Annular region 1111 Electrostatic chuck 112 Ring assembly 13 Shower head 2 Control unit 2a Computer 2a1 Processing unit 2a2 Memory unit 2a3 Communication interface 20 Gas supply unit 30 Power supply 31 RF power supply 32 DC power supply 40 Exhaust system 50 Base 50a Chiller unit 50b Flow path 50c Piping 500 Outer wall 500a Lower surface 501 Intermediate member 501a Upper surface 502 Support member 503 Adjusting member 504 Piping 51 Opening 52 Gap 53 Opening 54 Opening 55 Partition wall 60 Housing 600 Outer wall 601 Upper part 601a Lower surface 602 Lower part 602a Upper surface 603 Support member 604 Adjustment member 605 Piping

Claims

1. A structure for use in a plasma processing apparatus, comprising: a first member having a first surface; a second member having a second surface opposite the first surface; a plurality of support members provided between the first surface and the second surface; a plurality of adjustment members provided between the first surface and the second surface; and a cylindrical member passing through the space between the first surface and the second surface, wherein the plurality of support members are arranged at different densities in a first space below a first unit area on the first surface, in which the cylindrical member is not arranged, and in a second space below a second unit area on the first surface, in which the cylindrical member is arranged and which has the same volume as the first space, and wherein the plurality of adjustment members are arranged at different densities in the first space and the second space.

2. The structure of claim 1, wherein the first member, the second member, the support member, the adjustment member, and the tubular member are made of metal, ceramics, or MMC (Metal Matrix Composites).

3. A structure as described in claim 1 or 2, wherein the plurality of support members are arranged more densely in the first space than in the second space, and the plurality of adjustment members are arranged more densely in the second space than in the first space.

4. The structure according to claim 1, wherein the structure is a base through which a heat transfer fluid flows in a space between the first surface and the second surface, and the adjustment member is in contact with the heat transfer fluid.

5. A structure as described in claim 4, wherein a partition wall for rectifying the heat transfer fluid is provided in the space between the first surface and the second surface, and the adjusting members are arranged more densely on the downstream side of the heat transfer fluid than on the upstream side.

6. The structure of claim 5, wherein the thickness of the partition is 5 mm or less.

7. The structure of claim 4, wherein the heat transfer fluid is supplied from the center of the second surface into the space between the first surface and the second surface and discharged from the periphery of the second surface.

8. The structure according to claim 1, wherein the first member, the second member, the support member, the adjustment member, and the tubular member are made of a dielectric material.

9. The structure of claim 1 or 8, wherein the plurality of support members and the plurality of adjustment members are arranged more densely in the first space than in the second space.

10. The structure of claim 1, wherein the structure is a housing supporting a base.

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