Gas supply equipment, shower head, and piping

Abstract

The goal is to increase the conductance of the flow path while preventing gas discharge within the flow path. [Solution] The gas supply device comprises a first member formed of a conductive material, a second member formed of a conductive material and set to a different potential than the first member, and a pipe made of a dielectric material that circulates gas between the first member and the second member. One end of the pipe is inserted into an opening formed in the second member. Inside the pipe, a flow path is formed in a direction oblique to the direction from the first member to the second member. In the flow path of the pipe between the first member and the second member, there is a portion where the length of the cross-section of the flow path in the direction from the first member to the second member is shorter than the length of the flow path of the portion of the pipe inserted into the opening of the second member.

Description

Technical Field

[0001] Various aspects and embodiments of the present disclosure relate to gas supply devices, showerheads, and piping.

Background Art

[0002] Patent Document 1 below discloses that "in a plasma etching apparatus 100 that applies high-frequency power to a lower electrode 110 of a pair of electrodes provided opposite to each other inside an airtight processing container 102, plasmatizes a processing gas introduced between the electrodes, and performs a predetermined process on the surface of a workpiece, an electrostatic chuck 112 that adsorbs and holds the workpiece, and a heat transfer gas supply unit 120 that supplies a heat transfer gas for controlling the workpiece to a predetermined temperature to a minute space S between the workpiece and the electrodes are composed of a heat transfer gas supply pipe 162 inclined with respect to the electric field direction generated by the high-frequency power supplied to the electrodes and a heat transfer gas supply pipe coma portion 164."

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a gas supply device, a showerhead, and piping that can increase the conductance of a flow path while preventing discharge of gas in the flow path.

Means for Solving the Problems

[0005] A gas supply device in one aspect of this disclosure comprises a first member formed of a conductive material, a second member formed of a conductive material and set to a different potential than the first member, and a pipe formed of a dielectric material for circulating gas between the first member and the second member. One end of the pipe is inserted into an opening formed in the second member. Inside the pipe, a flow path is formed in a direction oblique to the direction from the first member to the second member. In the flow path of the pipe between the first member and the second member, there is a portion where the length of the cross-section of the flow path in the direction from the first member to the second member is shorter than the length of the flow path of the portion of the pipe inserted into the opening of the second member. [Effects of the Invention]

[0006] According to various aspects and embodiments of this disclosure, it is possible to increase the conductance of a flow path while preventing gas discharge in the flow path. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a schematic diagram showing an example of a plasma processing system. [Figure 2] Figure 2 is an enlarged cross-sectional view showing an example of a piping structure. [Figure 3] Figure 3 shows an example of the distribution of equipotential lines in the piping of Reference Example 1. [Figure 4] Figure 4 shows an example of the distribution of equipotential lines in the piping of Reference Example 2. [Figure 5] Figure 5 shows an example of the relationship between distance from the top plate and potential. [Figure 6] Figure 6 shows an example of the relationship between the distance from the top plate and the length of the cross-sectional area of ​​the flow path. [Figure 7] Figure 7 shows an example of the distribution of equipotential lines in the piping of this embodiment. [Figure 8] Figure 8 shows a comparison of the conductance in the piping of Reference Example 1, Reference Example 2, and this embodiment. [Figure 9]Figure 9 shows another example of the relationship between the distance from the top plate and the length of the channel cross-section. [Figure 10] Figure 10 is an enlarged cross-sectional view showing another example of a piping structure. [Figure 11] Figure 11 is an enlarged cross-sectional view showing another example of a flow path within a pipe. [Modes for carrying out the invention]

[0008] The following describes in detail embodiments of the gas supply device, shower head, and piping, based on the drawings. However, the gas supply device, shower head, and piping disclosed in the following embodiments are not limited to these.

[0009] Incidentally, when a pipe is installed between two conductors with a potential difference and gas is circulated within the pipe, if the length of the cross-section of the gas flow path in the direction of the electric field generated by the potential difference is long, the gas molecules circulating within the flow path may be accelerated by the electric field and discharge may occur. When a discharge occurs within the pipe, the inner wall of the pipe may be damaged, and particles generated from the damaged area may be scattered into the processing chamber along with the gas. To suppress such discharges within the pipe, the length of the cross-section of the gas flow path in the direction of the electric field may be shortened.

[0010] However, if the length of the cross-sectional area of ​​the flow path in the direction of the electric field is shortened, the conductance in the flow path decreases, making it difficult to increase the flow rate of gas circulating in the pipe or to quickly switch gases in the space where gas is supplied through the pipe.

[0011] Therefore, this disclosure provides a technology that can increase the conductance of a flow path while preventing gas discharge in the flow path.

[0012] [Configuration of the plasma processing system] The following describes an example of the configuration of a plasma processing system. Figure 1 is a schematic diagram showing an example of a plasma processing system. The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a control unit 2. 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 unit 11 and a gas introduction unit. The gas introduction unit is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a shower head 13. The substrate support unit 11 is located inside the plasma processing chamber 10. The shower head 13 is located above the substrate support unit 11. In one embodiment, the shower head 13 constitutes at least a part of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, the side walls 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s, and at least one gas outlet for discharging gas from the plasma processing space. The plasma processing chamber 10 is made of a conductor such as aluminum and is grounded. The shower head 13 and the substrate support portion 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0013] The substrate support portion 11 includes a main body portion 111 and a ring assembly 112. The main body portion 111 has a central region 111a for supporting the substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of the substrate W. The annular region 111b of the main body portion 111 surrounds the central region 111a of the main body portion 111 in a plan view. The substrate W is placed on the central region 111a of the main body portion 111, and the ring assembly 112 is placed on the annular region 111b of the main body portion 111 so as to surround the substrate W on the central region 111a of the main body portion 111. Therefore, the central region 111a is also called the substrate support surface for supporting the substrate W, and the annular region 111b is also called the ring support surface for supporting the ring assembly 112.

[0014] In one embodiment, the main body portion 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 can function as a lower electrode. The electrostatic chuck 1111 is disposed on the base 1110. 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 other members surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member, may have the annular region 111b. 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. Also, at least one RF / DC electrode coupled to an RF (Radio Frequency) power supply 31 and / or a DC (Direct Current) 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 1110 and the at least one RF / DC electrode may function as a plurality of lower electrodes. Also, the electrostatic electrode 1111b may function as a lower electrode. Therefore, the substrate support portion 11 includes at least one lower electrode.

[0015] 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 ring is formed of a conductive material or an insulating material, and the cover ring is formed of an insulating material.

[0016] Further, the substrate support portion 11 may include a temperature control 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 control module may include a heater, a heat transfer medium, a flow path 1110a, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path 1110a. In one embodiment, the flow path 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. Further, the substrate support portion 11 may include a heat transfer gas supply portion configured to supply a heat transfer gas to a gap between the back surface of the substrate W and the central region 111a.

[0017] The shower head 13 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The shower head 13 is an example of a gas supply device. The shower head 13 has at least one gas supply port 13a, a top plate 13b, an insulating member 13c, a holder 13d, at least one gas diffusion chamber 13e, a shower plate 13f, and a pipe 130. The top plate 13b is an example of a first member, and the holder 13d is an example of a second member.

[0018] The shower plate 13f has multiple through-holes, which are gas inlets 13g. The top plate 13b is made of a conductive material such as aluminum and is grounded via the side wall 10a of the plasma processing chamber 10. The holder 13d and the shower plate 13f are made of a conductive material such as aluminum. An insulating member 13c is placed between the lower surface 13b1 of the top plate 13b and the upper surface 13d1 of the holder 13d, insulating the top plate 13b and the holder 13d. The holder 13d is supported by the side wall 10a of the plasma processing chamber 10 via an insulating member 13h, and the holder 13d and the plasma processing chamber 10 are insulated by the insulating member 13h. The holder 13d detachably holds the shower plate 13f. The holder 13d is connected to a power supply 30, and the holder 13d and the shower plate 13f are maintained at a predetermined potential (e.g., -1.2kV).

[0019] The processing gas supplied to the gas supply port 13a is supplied to the gas diffusion chamber 13e via the piping 130. The processing gas supplied to the gas diffusion chamber 13e diffuses within the gas diffusion chamber 13e and is introduced into the plasma processing space 10s from the gas inlet 13g of the shower plate 13f. The holder 13d and the shower plate 13f function as at least one upper electrode. In addition to the shower head 13, the gas introduction section may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 10a.

[0020] 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 processing gas to the shower head 13 from a corresponding gas source 21 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 20 may include one or more flow modulation devices that modulate or pulse the flow rate of at least one processing gas.

[0021] 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 causes plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Thus, the RF power supply 31 can function as at least part of a plasma generation unit configured to generate plasma from one or more processing gases in the plasma processing chamber 10. In addition, by supplying a bias RF signal to at least one lower electrode, a bias potential is generated on the substrate W, and ionic components in the formed plasma can be drawn into the substrate W.

[0022] In one embodiment, the RF power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation 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 generation unit 31a may be configured to generate a plurality of source RF signals having different frequencies. One or more generated source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0023] The second RF generation unit 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 generation unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. One or more generated 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.

[0024] 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 generation unit 32a and a second DC generation unit 32b. In one embodiment, the first DC generation unit 32a is connected to at least one lower electrode and configured to generate a first DC signal. The generated first bias DC signal is applied to at least one lower electrode. In one embodiment, the second DC generation unit 32b is connected to at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to at least one upper electrode.

[0025] In various embodiments, at least one of 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 generation unit for generating a sequence of voltage pulses from a DC signal is connected between the first DC generation unit 32a and at least one lower electrode. Thus, the first DC generation unit 32a and the waveform generation unit constitute a voltage pulse generation unit. When the second DC generation unit 32b and the waveform generation unit constitute a voltage pulse generation unit, the voltage pulse generation unit is connected to at least one upper electrode. The voltage pulses may have positive or negative polarity. The sequence of voltage pulses may also include one or more positive voltage pulses and one or more negative voltage pulses within one cycle. The first and second DC generation units 32a and 32b may be provided in addition to the RF power supply 31, and the first DC generation unit 32a may be provided in place of the second RF generation unit 31b.

[0026] The exhaust system 40 may be connected to, for example, a gas outlet 10e located 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 regulating valve regulates the pressure in the plasma processing space 10s. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0027] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described herein. The control unit 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 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 is implemented, for example, by a computer 2a. The processing unit 2a1 may be configured to perform various control operations by reading a program from the storage unit 2a2 and executing the read program. This program may be stored in the storage unit 2a2 in advance, or it may be obtained via a medium when needed. The obtained program is stored in the storage unit 2a2 and read from the storage unit 2a2 and executed by the processing unit 2a1. The medium may be various storage media readable by the computer 2a, or it may be a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). The memory unit 2a2 may include RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing device 1 via a communication line such as a LAN (Local Area Network).

[0028] [Structure of piping 130] Figure 2 is an enlarged cross-sectional view showing an example of the structure of the piping 130. In this embodiment, the piping 130 is made of a dielectric material such as polyimide or PCTFE (polychlorotrifluoroethylene) and is placed between the top plate 13b and the holder 13d. In this embodiment, one end of the piping 130 on the holder 13d side is inserted into an opening 13d2 formed in the holder 13d. Sealing members 131, such as O-rings, are placed between the top plate 13b and the piping 130, and between the holder 13d and the piping 130.

[0029] A gas flow path 132 is formed inside the piping 130. The flow path 132 is formed to extend in a direction oblique to the direction from the top plate 13b to the holder 13d (the direction of the arrow in Figure 2). In this embodiment, the flow path 132 is formed spirally inside the piping 130. One end of the flow path 132 on the holder 13d side communicates with the gas diffusion chamber 13e via the flow path 13d3, and the other end of the flow path 132 on the top plate 13b side communicates with the gas supply port 13a via the flow path 13b2 of the gas supply port 13a.

[0030] In the portion of the piping 130 between the top plate 13b and the holder 13d, the channel 132 has a section where the cross-sectional length L1 of the channel 132 in the direction of the arrow in Figure 2 is shorter than the cross-sectional length L2 of the channel 132 in the portion of the piping 130 inserted into the opening 13d2 of the holder 13d. In the example in Figure 2, the channel 132a of the piping 130 in the portion corresponding to region R1 in Figure 2 has a cross-sectional length L1 in the direction of the arrow in Figure 2, which is shorter than the cross-sectional length L2 of the channel 132b of the piping 130 inserted into the opening 13d2 of the holder 13d (the portion corresponding to region R2 in Figure 2). For example, the channel 132 of the piping 130 is configured such that the cross-sectional length of the channel 132 in the direction of the arrow in Figure 2 continuously increases as it progresses along the channel from the top plate 13b side to the holder 13d side. Furthermore, in the portion of the piping 130 corresponding to area R1 in Figure 2, there may be a portion of the flow path 132 where the length of the cross-section of the flow path 132 in the direction of the arrow in Figure 2 is approximately the same as the length of the cross-section of the flow path 132b of the piping 130 that is inserted into the opening 13d2 of the holder 13d.

[0031] Furthermore, in this embodiment, the length of the cross-section of the flow path 132 in the direction of the arrow in Figure 2 is such that the potential difference between the wall surface of the flow path 132 on the top plate 13b side and the wall surface of the flow path 132 on the holder 13d side is less than the discharge initiation voltage of Ar gas. Among gases, Ar gas has a low discharge initiation voltage. Therefore, by setting the length of the cross-section of the flow path 132 in the direction of the arrow in Figure 2 to a length that does not cause Ar gas discharge, it is possible to suppress the occurrence of discharge in the flow path 132 even when Ar gas and other gases are flowed through it.

[0032] [Reference example 1] Here, we consider a pipe 130' as Reference Example 1, which is positioned only in the region R1 between the top plate 13b and the holder 13d, with one end not inserted into the opening of the holder 13d. Figure 3 shows an example of the distribution of equipotential lines 133 in the pipe 130' of Reference Example 1. In Figure 3, only half of the pipe 130' is shown. Also, in Figure 3, the sealing member 131 is not shown.

[0033] As illustrated in Figure 3, in the piping 130' of Reference Example 1, the density of equipotential lines 133 within the piping 130' is high. Therefore, if the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d (direction of the arrow in Figure 3) is increased, the potential difference between the wall surface of the flow path 132 on the top plate 13b side and the wall surface of the flow path 132 on the holder 13d side becomes larger. When the potential difference between the wall surface of the flow path 132 on the top plate 13b side and the wall surface of the flow path 132 on the holder 13d side exceeds the discharge initiation voltage of the gas flowing through the flow path 132, a discharge will occur within the flow path 132.

[0034] Therefore, in order to suppress gas discharge in the flow path 132, the length of the cross-section of the flow path 132 in the direction of the arrow in Figure 3 must be shortened. Shortening the length of the cross-section of the flow path 132 in the direction of the arrow in Figure 3 reduces the conductance of the flow path 132, making it difficult to increase the flow rate of gas circulating in the flow path 132 or to quickly switch gases in the plasma processing space 10s through which the gas is supplied.

[0035] [Reference example 2] Next, consider a pipe 130" as Reference Example 2, which has a portion located in the region R1 between the top plate 13b and the holder 13d, and a portion inserted into the opening 13d2 of the holder 13d. Figure 4 shows an example of the distribution of equipotential lines 133 in the pipe 130" of Reference Example 2. In Figure 4, only half of the pipe 130" is shown. Also, in Figure 4, the illustration of the sealing member 131 is omitted.

[0036] As illustrated in Figure 4, in the piping 130" of Reference Example 2, the density of equipotential lines 133 in the portion of piping 130" corresponding to region R2 in Figure 4 is lower than the density of equipotential lines 133 in the portion of piping 130" corresponding to region R1 in Figure 4. Also, in the example in Figure 4, the equipotential lines 133 protrude into the portion of piping 130" corresponding to region R2 in Figure 4. As a result, the density of equipotential lines 133 in the portion of piping 130" on the holder 13d side of region R1 in Figure 4 is lower than the density of equipotential lines 133 in the portion of piping 130" on the top plate 13b side of region R1 in Figure 3.

[0037] In the piping 130" of Reference Example 2, the relationship between the distance from the top plate 13b and the potential in the direction of the arrow in Figure 4, with the holder 13d side of the top plate 13b as the reference, can be illustrated as shown in Figure 5, for example. In the example in Figure 5, a DC voltage of -1.2kV is applied to the holder 13d, and a potential difference of 1.2kV is generated between the top plate 13b and the holder 13d.

[0038] As illustrated in Figure 5, the potential changes significantly in the vicinity of holder 13d in response to changes in distance from holder 13d, and the change in potential decreases as the distance from holder 13d increases. In other words, the amount of change in the electric field is large in the vicinity of holder 13d, and the amount of change in the electric field decreases as the distance from holder 13d increases.

[0039] Here, plotting the length of the cross-section of the channel 132 where the potential difference between the wall surface of the channel 132 on the top plate 13b side and the wall surface of the channel 132 on the holder 13d side is constant, against the distance from the top plate 13b, results in something like Figure 6. As illustrated in Figure 6, the length of the cross-section of the channel 132 where the potential difference between the wall surface of the channel 132 on the top plate 13b side and the wall surface of the channel 132 on the holder 13d side is constant increases as the distance from the holder 13d increases. That is, in Reference Example 2, the length of the cross-section of the channel 132 in the direction of the arrow in Figure 4 can be increased as the distance from the holder 13d increases, within a range that is the same as or shorter than the length of the cross-section of the channel 132 illustrated in Figure 6.

[0040] Figure 7 shows an example of the distribution of equipotential lines 133 in the piping 130 of this embodiment. In Figure 7, only half of the piping 130 is shown. Also, in Figure 7, the sealing member 131 is not shown. In this embodiment, for example, as shown in Figure 7, the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d (the direction of the arrow in Figure 7) increases as it moves away from the holder 13d. As a result, the cross-sectional area of ​​the flow path 132 can be increased within a range where the potential difference between the wall surface of the flow path 132 on the top plate 13b side and the wall surface of the flow path 132 on the holder 13d side is below a certain value, and the conductance of the flow path 132 can be increased.

[0041] [Comparison of conductance in channel 132] Figure 8 shows a comparison of the conductance in the piping of Reference Example 1, Reference Example 2, and this embodiment. In the piping 130' of Reference Example 1 (see Figure 3), the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d is set to 1 mm regardless of the distance from the holder 13d, and the maximum voltage applied to the flow path 132 is 148 V. Furthermore, in the piping 130" of Reference Example 2 (see Figure 4), the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d is set to 1.6 mm regardless of the distance from the holder 13d, and the maximum voltage applied to the flow path 132 is 144.3 V. Also, in the piping 130 of this embodiment (see Figures 2 and 7), the minimum length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d is set to 1.6 mm and the maximum length is set to 4.0 mm, and the maximum voltage applied to the flow path 132 is 144.3 V. In Figure 8, in all of Reference Example 1, Reference Example 2, and this embodiment, the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d is set to a length that results in a potential difference lower than 178 V, which is the discharge initiation voltage of Ar gas.

[0042] For example, as shown in Figure 8, among Reference Example 1, Reference Example 2, and this embodiment, the conductance of the flow path 132 is highest in the flow path 132 of this embodiment. Therefore, in the piping 130 of this embodiment, the conductance of the flow path 132 can be increased while preventing gas discharge in the flow path 132. Also, comparing Reference Example 2 with this embodiment, the rise time, which is the time until a predetermined flow rate of gas is introduced into the plasma processing chamber 10, is shorter for the piping 130 of this embodiment than for the piping 130 of Reference Example 2. As a result, in the piping 130 of this embodiment, the gas in the plasma processing chamber 10 can be switched quickly via the piping 130. Furthermore, from the viewpoint of increasing the conductance of the flow path 132, the length of the cross-section of the flow path 132 (width of the flow path 132) in the direction intersecting the direction from the top plate 13b to the holder 13d may be increased.

[0043] The embodiments have been described above. As described above, the shower head 13 in this embodiment comprises a top plate 13b made of a conductive material, a holder 13d made of a conductive material and set to a different potential from the top plate 13b, and a pipe 130 made of a dielectric material that allows gas to flow between the top plate 13b and the holder 13d. One end of the pipe 130 is inserted into an opening 13d2 formed in the holder 13d. Inside the pipe 130, a flow path is formed in a direction oblique to the direction from the top plate 13b to the holder 13d. In the flow path 132 of the pipe 130 between the top plate 13b and the holder 13d, there is a portion where the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d is shorter than the length of the flow path 132 of the pipe 130 inserted into the opening 13d2 of the holder 13d. This makes it possible to increase the conductance of the flow path 132 while preventing gas discharge in the flow path 132.

[0044] Furthermore, in the embodiment described above, the length of the cross-section of the flow path 132 of the piping 130 in the direction from the top plate 13b to the holder 13d increases continuously from the top plate 13b side to the holder 13d side along the direction of extension of the flow path 132. This suppresses gas stagnation within the flow path 132 and allows for a smooth gas flow.

[0045] Furthermore, in the embodiment described above, the flow path 132 is formed in a spiral shape within the pipe 130. This makes it possible to miniaturize the pipe 130.

[0046] Furthermore, in the embodiment described above, the length of the cross-section of the flow path 132 of the piping 130 in the direction from the top plate 13b to the holder 13d is such that the potential difference between the wall surface of the flow path 132 on the top plate 13b side and the wall surface of the flow path 132 on the holder 13d side is less than the discharge initiation voltage of Ar gas. Among gases, Ar gas has a low discharge initiation voltage. Therefore, the piping 130 of this embodiment can increase the conductance of the flow path 132 while preventing the discharge of gas in the flow path 132, even when any gas is circulated through it.

[0047] Furthermore, in the embodiment described above, the piping 130 is made of polyimide. This makes it easy to manufacture the piping 130.

[0048] Furthermore, the above-described embodiment is a shower head 13 comprising a top plate 13b, a holder 13d, a shower plate 13f, and piping 130. The top plate 13b is made of a conductive material and is grounded. The holder 13d is made of a conductive material and is insulated from the top plate 13b. The shower plate 13f is made of a conductive material, has a plurality of through holes, and is held by the holder 13d. The piping 130 is made of a dielectric material, is positioned between the top plate 13b and the holder 13d, and supplies gas to a gas diffusion chamber 13e between the holder 13d and the shower plate 13f via the top plate 13b. A predetermined voltage is applied to the top plate 13b and the shower plate 13f. One end of the piping 130 is inserted into an opening 13d2 formed in the holder 13d, and a flow path is formed inside the piping 130 in a direction oblique to the direction from the top plate 13b to the holder 13d. In the section of the piping 130 between the top plate 13b and the holder 13d, the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d is shorter than the length of the flow path 132 in the section of the piping 130 inserted into the opening 13d2 of the holder 13d. This makes it possible to increase the conductance of the flow path 132 while preventing gas discharge in the flow path 132.

[0049] [others] Furthermore, the technology disclosed in this application is not limited to the embodiments described above, and numerous modifications are possible within the scope of its essence.

[0050] For example, in the embodiment described above, the flow path 132 of the piping 130 is configured such that the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d increases continuously as it progresses along the flow path from the top plate 13b side to the holder 13d side. However, the disclosed technology is not limited to this. In other embodiments, the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d may be configured to increase in a stepwise manner as it progresses along the flow path from the top plate 13b side to the holder 13d side, for example, as shown by the dashed line in Figure 9. This makes it possible to easily manufacture the piping 130.

[0051] Furthermore, in the embodiment described above, one flow path 132 is formed in the pipe 130, but the disclosed technology is not limited to this, and multiple flow paths 132 may be formed in the pipe 130. This makes it possible to supply multiple different gases using a single pipe 130. The same gas may also be flowed through each of the multiple flow paths 132 formed in the pipe 130.

[0052] Furthermore, in the embodiment described above, one end of the piping 130 is inserted into the opening 13d2 formed in the holder 13d, but the disclosed technology is not limited to this. In another embodiment, the other end of the piping 130 may be inserted into the opening formed in the top plate 13b. Also, in the flow path 132 of the piping 130 between the top plate 13b and the holder 13d, there is a portion where the length of the cross-section of the flow path 132 in the direction from the top plate 13b toward the holder 13d is shorter than the length of the flow path 132 of the piping 130 inserted into the opening in the top plate 13b. Even in this embodiment, the electric field acting on the flow path 132 of the piping 130 inserted into the opening in the top plate 13b is weakened. Therefore, in the piping 130 inserted into the opening in the top plate 13b, the length of the cross-section of the flow path 132 in the direction from the top plate 13b toward the holder 13d can be increased, and the conductance of the flow path 132 can be increased. Alternatively, one end of the pipe 130 may be inserted into the opening 13d2 formed in the holder 13d, and the other end of the pipe 130 may be inserted into the opening formed in the top plate 13b.

[0053] Furthermore, in the embodiments described above, the piping 130 is formed from a single dielectric material, but the disclosed technology is not limited to this, and the piping 130 may be formed from multiple materials with different dielectric constants. For example, as shown in Figure 10, the piping 130 may be formed from materials with different dielectric constants. In the example in Figure 10, the piping 130 has a first dielectric 130a and a second dielectric 130b having a higher dielectric constant than the first dielectric 130a. Also, in the example in Figure 10, at least a portion of the piping 130 between the top plate 13b and the holder 13d (region R1) is formed from the first dielectric 130a. This makes it possible to weaken the electric field applied to the flow path 132 of the piping 130 in region R1 compared to when the piping 130 is formed from the same dielectric. Therefore, the length of the cross-section of the flow path 132 in region R1 in the direction from the top plate 13b to the holder 13d can be increased, and the conductance of the flow path 132 can be increased.

[0054] Furthermore, in the embodiment described above, a spiral flow path 132 is formed inside the piping 130, but the disclosed technology is not limited to this. The shape of the flow path 132 formed inside the piping 130 does not have to be spiral, as long as it is formed to extend in a direction oblique to the direction from the top plate 13b to the holder 13d, and may be a straight flow path 132, for example, as shown in Figure 11. However, even in the example of Figure 11, the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d is configured to gradually increase as the flow path progresses from the top plate 13b side to the holder 13d side. Also, in the example of Figure 11, the length of the cross-section of the flow path 132 in the direction from the top plate 13b to the holder 13d is such that the potential difference between the wall surface of the flow path 132 on the top plate 13b side and the wall surface of the flow path 132 on the holder 13d side is less than the discharge initiation voltage of Ar gas. Even with a flow channel 132 of this shape, it is possible to increase the conductance of the flow channel 132 while preventing gas discharge within the flow channel 132.

[0055] Furthermore, in the embodiment described above, the piping 130 is provided inside the shower head 13, but the disclosed technology is not limited to this. Any piping that allows gas to flow between two conductive members with a potential difference may be provided in parts other than the shower head 13, such as piping for supplying heat transfer gas between the substrate W and the electrostatic chuck 1111.

[0056] Furthermore, in the above-described embodiment, a plasma processing apparatus 1 that uses capacitively coupled plasma (CCP) as an example of a plasma source was explained, but the plasma source is not limited to capacitively coupled plasma. Examples of plasma sources other than capacitively coupled plasma include inductively coupled plasma (ICP), microwave-excited surface wave plasma (SWP), electron cycloton resonance plasma (ECP), and helicon wave-excited plasma (HWP).

[0057] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. Indeed, the embodiments described above can be embodied in a variety of forms. Furthermore, the embodiments described above may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims.

[0058] Furthermore, the following additional information is disclosed regarding the above embodiments.

[0059] (Note 1) A first member formed of a conductive material, A second member formed of a conductive material and set to a different potential from the first member, A pipe formed of a dielectric material, through which gas flows between the first member and the second member. Equipped with, One end of the aforementioned pipe is inserted into an opening formed in the second member. A flow path is formed inside the aforementioned piping in a direction oblique to the direction from the first member to the second member. A gas supply device in which the flow path of the piping between the first member and the second member has a portion where the length of the cross-section of the flow path in the direction from the first member to the second member is shorter than the length of the flow path of the piping in the portion inserted into the opening of the second member. (Note 2) The gas supply device according to Appendix 1, wherein the length of the cross-section of the flow path of the piping in the direction from the first member to the second member is continuously increased from the first member side to the second member side along the extending direction of the flow path. (Note 3) The gas supply device according to Appendix 1, wherein the length of the cross-section of the flow path of the piping in the direction from the first member to the second member increases in a stepwise manner from the first member side to the second member side along the extending direction of the flow path. (Note 4) The gas supply device according to any one of the appendices 1 to 3, wherein the flow path is formed spirally within the piping. (Note 5) The gas supply device according to any one of the appendices 1 to 4, wherein a plurality of the aforementioned flow paths are formed in the piping. (Note 6) The other end of the piping is inserted into the opening formed in the first member. The gas supply device according to any one of the appendices 1 to 5, wherein the flow path of the piping between the first member and the second member has a portion where the length of the cross-section of the flow path in the direction from the first member to the second member is shorter than the length of the flow path of the piping in the portion inserted into the opening of the first member. (Note 7) The length of the cross-sectional area of ​​the flow path of the piping in the direction from the first member to the second member is: The gas supply device according to any one of the appendices 1 to 6, wherein the length of the device is such that the potential difference between the wall surface of the flow path on the first member side and the wall surface of the flow path on the second member side is less than the discharge initiation voltage of Ar gas. (Note 8) The aforementioned piping is made of polyimide and is a gas supply device according to any one of the appendices 1 to 7. (Note 9) The piping is formed of a first dielectric and a second dielectric having a higher dielectric constant than the first dielectric. At least a portion of the piping between the first member and the second member is formed of the first dielectric material. The gas supply device according to any one of the appendices 1 to 7, wherein the portion of the piping inserted into the second member is formed of the second dielectric. (Note 10) A top plate formed of a conductive material and grounded, A holder formed of a conductive material and insulated from the top plate, A shower plate formed of a conductive material, having multiple through holes, and held in the holder, A pipe formed of a dielectric material, positioned between the top plate and the holder, and supplying gas to the space between the holder and the shower plate via the top plate. Equipped with, A predetermined voltage is applied to the holder and the shower plate. One end of the aforementioned pipe is inserted into an opening formed in the holder. A flow path is formed inside the aforementioned piping in a direction oblique to the direction from the top plate toward the holder. A shower head in which the flow path of the piping between the top plate and the holder has a portion where the length of the cross-section of the flow path in the direction from the top plate to the holder is shorter than the length of the flow path of the piping in the portion inserted into the opening of the holder. (Note 11) A dielectric pipe for circulating gas between a first member made of a conductive material and a second member made of a conductive material and set to a different potential from the first member, One end of the aforementioned pipe is inserted into an opening formed in the second member. A flow path is formed inside the aforementioned piping in a direction oblique to the direction from the first member to the second member. A pipe in which the flow path of the pipe between the first member and the second member has a portion where the length of the cross-section of the flow path in the direction from the first member to the second member is shorter than the length of the flow path of the pipe in the portion inserted into the opening of the second member. [Explanation of symbols]

[0060] R region W board 1. Plasma processing equipment 10 Plasma processing chamber 10a side wall 10e Gas outlet 10s Plasma Processing Space 11. Substrate support section 111 Main body 111a Central area 111b Circular region 1110 base 1110a flow path 1111 Electrostatic Chuck 1111a Ceramic component 1111b Electrostatic electrode 112 Ring Assembly 13 Shower head 13a Gas supply port 13b Top Plate 13b1 Bottom surface 13b2 channel 13c insulating material 13d holder 13d1 Top surface 13d2 opening 13d3 channel 13e Gas Diffusion Chamber 13f Shower Plate 13g gas inlet 13h Insulating material 130 Piping 130a First dielectric 130b Second dielectric 131 Sealing member 132 channels 20 Gas Supply Department 21 Gas Source 22 Flow controller 30 power supply 31 RF power supply 31a First RF generation unit 31b Second RF generation unit 32 DC power supply 32a First DC generation unit 32b Second DC generation unit 40 Exhaust System 2 Control Unit 2a Computer 2a1 Processing Unit 2a2 Storage section 2a3 communication interface

Claims

1. A first member formed of a conductive material, A second member formed of a conductive material and set to a different potential from the first member, A pipe formed of a dielectric material, through which gas flows between the first member and the second member. Equipped with, One end of the piping is inserted into an opening formed in the second member. A flow path is formed inside the piping in a direction oblique to the direction from the first member to the second member. A gas supply device in which the flow path of the piping between the first member and the second member has a portion where the length of the cross-section of the flow path in the direction from the first member to the second member is shorter than the length of the flow path of the piping in the portion inserted into the opening of the second member.

2. The gas supply device according to claim 1, wherein the length of the cross-section of the flow path of the piping in the direction from the first member to the second member is continuously increased from the first member side to the second member side along the extending direction of the flow path.

3. The gas supply device according to claim 1, wherein the length of the cross-section of the flow path of the piping in the direction from the first member to the second member increases in a stepwise manner from the first member side to the second member side along the extending direction of the flow path.

4. The gas supply device according to any one of claims 1 to 3, wherein the flow path is formed in a spiral shape within the piping.

5. The gas supply device according to claim 1, wherein a plurality of the aforementioned flow paths are formed in the aforementioned piping.

6. The other end of the piping is inserted into the opening formed in the first member. The gas supply device according to claim 1, wherein the flow path of the piping between the first member and the second member has a portion where the length of the cross-section of the flow path in the direction from the first member to the second member is shorter than the length of the flow path of the piping in the portion inserted into the opening of the first member.

7. The length of the cross-sectional area of ​​the flow path of the piping in the direction from the first member to the second member is: The gas supply device according to claim 1, wherein the length of the channel is such that the potential difference between the wall surface of the channel on the first member side and the wall surface of the channel on the second member side is less than the discharge initiation voltage of Ar gas.

8. The gas supply device according to claim 1, wherein the piping is made of polyimide.

9. The piping is formed of a first dielectric and a second dielectric having a higher dielectric constant than the first dielectric. At least a portion of the piping between the first member and the second member is formed of the first dielectric material. The gas supply device according to claim 1, wherein the portion of the piping inserted into the second member is formed of the second dielectric material.

10. A top plate formed of a conductive material and grounded, A holder formed of a conductive material and insulated from the top plate, A shower plate formed of a conductive material, having multiple through holes, and held in the holder, A pipe formed of a dielectric material, positioned between the top plate and the holder, and supplying gas to the space between the holder and the shower plate via the top plate. Equipped with, A predetermined voltage is applied to the holder and the shower plate. One end of the aforementioned pipe is inserted into an opening formed in the holder. A flow path is formed inside the aforementioned piping in a direction oblique to the direction from the top plate toward the holder. A shower head in which the flow path of the piping between the top plate and the holder has a portion where the length of the cross-section of the flow path in the direction from the top plate to the holder is shorter than the length of the flow path of the piping in the portion inserted into the opening of the holder.

11. A dielectric pipe for circulating gas between a first member made of a conductive material and a second member made of a conductive material and set to a different potential from the first member, One end of the piping is inserted into an opening formed in the second member. A flow path is formed inside the piping in a direction oblique to the direction from the first member to the second member. A pipe in which the flow path of the pipe between the first member and the second member has a portion where the length of the cross-section of the flow path in the direction from the first member to the second member is shorter than the length of the flow path of the pipe in the portion inserted into the opening of the second member.

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