Plasma processing apparatus

Abstract

To provide a plasma processing apparatus in which a ring assembly can be properly positioned with respect to a substrate support portion.SOLUTION: A plasma processing apparatus is provided, comprising: a plasma processing chamber; a substrate supporting portion having a substrate supporting surface and a ring supporting surface; an insulating ring having at least three through-holes, each of the through-holes having an upper hole portion having a first width in a radial direction of the insulating ring and a second width smaller than the first width in a peripheral direction of the insulating ring and a lower hole portion having a flaring shape expanded toward a lower side in view from a lateral side; a conductive ring having at least three grooves corresponding to each through-hole of the lower surface, each groove having a third width in the radial direction of the conductive ring and a fourth width in the peripheral direction of the conductive ring, the fourth width being smaller than the third width; at least three lift pins corresponding to each groove; and at least one actuator.SELECTED DRAWING: Figure 4A

Description

Technical Field

[0001] This disclosure relates to a plasma processing apparatus.

Background Art

[0002] Patent Document 1 discloses a substrate support base having an annular member placement surface on which an annular member is placed and three or more lifters configured to be able to project from the annular member placement surface. According to the description of Patent Document 1, recesses formed from concave surfaces that are recessed upward are provided at positions corresponding to each of the lifters on the bottom surface of the annular member, and in a plan view, the recesses are formed larger than the conveyance accuracy of the annular member upward from the annular member placement surface and also larger than the upper end portions of the lifters. Further, the upper end portions of the lifters are formed in a hemispherical shape, and the concave surfaces are formed with a smaller curvature than the concave surfaces forming the hemispherical shape of the upper end portions of the lifters.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technology according to this disclosure provides a plasma processing apparatus capable of appropriately positioning a ring assembly with respect to a substrate support portion.

Means for Solving the Problems

[0005] One aspect of the present disclosure is a plasma processing apparatus for processing a substrate, comprising: a plasma processing chamber; a substrate support portion disposed within the plasma processing chamber and having a substrate support surface and a ring support surface; an insulating ring disposed on the ring support surface and having at least three through holes, each of the at least three through holes having an upper hole portion and a lower hole portion, the upper hole portion having a first width in the radial direction of the insulating ring and a second width in the circumferential direction of the insulating ring, the second width being smaller than the first width, and the lower hole portion having a flared shape that widens downward when viewed from the side; and a conductive ring supported by the insulating ring and having at least three grooves on its lower surface corresponding to each of the at least three through holes, each of the at least three grooves being in the radial direction of the conductive ring A conductive ring having a third width in the direction and a fourth width in the circumferential direction of the conductive ring, wherein the fourth width is smaller than the third width; at least three lift pins positioned below the ring support surface and corresponding to each of the at least three grooves, wherein each of the at least three lift pins has an upper support portion and a lower support portion, the upper support portion configured to support the conductive ring from below by contacting the bottom surface of the groove of the conductive ring through the through hole of the insulating ring, and the lower support portion configured to support the insulating ring from below by contacting the inclined surface of the insulating ring defining the lower hole portion; and at least one actuator configured to move the at least three lift pins in the longitudinal direction. [Effects of the Invention]

[0006] According to this disclosure, it is possible to provide a plasma processing apparatus that enables proper positioning of a ring assembly with respect to a substrate support portion. [Brief explanation of the drawing]

[0007] [Figure 1] This is an explanatory diagram showing the general configuration of the plasma processing system. [Figure 2] This is a longitudinal cross-sectional view showing a schematic configuration of the plasma processing apparatus according to the embodiment. [Figure 3] This is a magnified view of a portion of Figure 2. [Figure 4A] This is an explanatory diagram illustrating the general structure of the insulating ring. [Figure 4B] This is an explanatory diagram illustrating the general structure of the insulating ring. [Figure 5A] This is an explanatory diagram illustrating the general structure of the inner edge ring. [Figure 5B] This is an explanatory diagram illustrating the general structure of the inner edge ring. [Figure 6A] This is an explanatory diagram showing another example of groove formation relative to the inner edge ring. [Figure 6B] This is an explanatory diagram showing another example of groove formation relative to the inner edge ring. [Figure 6C] This is an explanatory diagram showing another example of forming through holes in an insulating ring. [Figure 7] This figure shows the process of replacing a ring assembly. [Figure 8] This figure shows the process of replacing a ring assembly. [Figure 9] This figure shows the process of replacing a ring assembly. [Figure 10A] This figure shows the process of replacing a ring assembly. [Figure 10B] This figure shows the process of replacing a ring assembly. [Figure 11A] This figure shows another example of the inner edge ring configuration. [Figure 11B] This figure shows another example of the inner edge ring configuration. [Figure 11C] This figure shows another example of the inner edge ring configuration. [Figure 12A] This is an explanatory diagram showing another example of groove formation relative to the inner edge ring. [Figure 12B] This is an explanatory diagram showing another example of groove formation relative to the inner edge ring. [Figure 12C] This is an explanatory diagram showing another example of groove formation relative to the inner edge ring. [Figure 12D] It is an explanatory diagram showing another formation example of a groove with respect to an inner edge ring. [Figure 13A] It is an explanatory diagram showing another formation example of a groove with respect to an inner edge ring. [Figure 13B] It is an explanatory diagram showing another formation example of a groove with respect to an inner edge ring. [Figure 13C] It is an explanatory diagram showing another formation example of a groove with respect to an inner edge ring.

Embodiments for Carrying Out the Invention

[0008] In a manufacturing process of a semiconductor device or the like, plasma processing such as etching is performed on a semiconductor substrate (hereinafter simply referred to as "substrate") using plasma. The plasma processing is performed in a state where the substrate is placed on a substrate support portion disposed in a processing container configured to be depressurized.

[0009] Also, this substrate support base includes a plurality of annular members disposed so as to surround the periphery of the substrate on the substrate support portion in order to obtain good and uniform processing results at the central portion and the peripheral portion of the substrate during plasma processing. The plurality of annular members include an edge ring disposed adjacent to the substrate on the substrate support portion and a cover ring disposed so as to cover the outer surface of the edge ring. Since these annular members are consumed by being exposed to plasma, periodic replacement is required. The replacement of the annular members is performed, for example, using a lifter that moves up and down while supporting the annular members and a transport mechanism that transports the annular members.

[0010] Here, when replacing the annular members using these lifters and transport mechanisms, for example, due to the transport accuracy by the transport mechanism or the like, there may be a case where these annular members cannot be appropriately arranged at a desired position on the substrate support portion. And, in realizing the transport function of the annular members in recent years, improvement in the installation accuracy of the annular members with respect to the substrate support portion is more required as compared with the transport accuracy by the transport mechanism.

[0011] In the plasma processing apparatus described in Patent Document 1, a groove larger than the transport accuracy of the transport mechanism is formed on the bottom surface of the edge ring, and a through hole larger than the transport accuracy of the transport mechanism is formed in the covering ring, thereby improving the positioning accuracy of the annular member. However, when an annular member is replaced using the plasma processing apparatus shown in Patent Document 1, if a relative misalignment occurs between the lifter and the groove (through hole) due to the effects of machine error (e.g., machining tolerance) or thermal expansion of the annular member, the positioning accuracy of the annular member may deteriorate, or the lifter or annular member may be damaged.

[0012] The technology described herein has been made in view of the above circumstances and provides a plasma processing apparatus capable of appropriately positioning a ring assembly with respect to a substrate support. A plasma processing system comprising the substrate processing apparatus according to this embodiment will be described below with reference to the drawings. In this specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals to avoid redundant explanations.

[0013] <Plasma Treatment System> In one embodiment, the plasma processing system includes a plasma processing apparatus 1, a transport apparatus 2, and a control unit 3, as shown in Figure 1. 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 section 11, and a plasma generation section 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 outlet for discharging gas from the plasma processing space. The gas supply port is connected to a gas supply section 20, which will be described later, and the gas outlet is connected to an exhaust system 40, which will be described later. The substrate support section 11 is located in the plasma processing space and has a substrate support surface for supporting a substrate.

[0014] The plasma generation 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 a capacitively coupled plasma (CCP), an inductively coupled plasma (ICP), an electron-cyclotron-resonance plasma (ECR), a helicon wave plasma (HWP), or a surface wave plasma (SWP), etc. Various types of plasma generation units, including an AC (Alternating Current) plasma generation unit and a DC (Direct Current) plasma generation unit, may also be used. In one embodiment, the AC signal (AC power) used in the AC plasma generation unit has a frequency in the range of 100 kHz to 10 GHz. Therefore, the AC signal includes an RF (Radio Frequency) signal and a microwave signal. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0015] The transport device 2 includes a transport arm 2a that holds and transports the substrate W and the ring assembly 120, which will be described later. A wafer is an example of the substrate W. The transport device 2 is configured to transport the substrate W and the ring assembly 120 between, for example, the outside of the plasma processing apparatus 1 and the substrate support section 11 located inside the plasma processing apparatus 1.

[0016] The control unit 3 processes computer-executable instructions that cause the plasma processing apparatus 1 and the transport apparatus 2 to perform the various processes described herein. The control unit 3 may be configured to control each element of the plasma processing apparatus 1 and the transport apparatus 2 to perform the various processes described herein. In one embodiment, part or all of the control unit 3 may be included in the plasma processing apparatus 1. The control unit 3 may include a processing unit 3a1, a storage unit 3a2, and a communication interface 3a3. The control unit 3 is implemented, for example, by a computer 3a. The processing unit 3a1 may be configured to perform various control operations by reading a program from the storage unit 3a2 and executing the read program. This program may be stored in the storage unit 3a2 in advance, or it may be obtained via a medium when needed. The obtained program is stored in the storage unit 3a2 and read from the storage unit 3a2 and executed by the processing unit 3a1. The medium may be various storage media readable by the computer 3a, or it may be a communication line connected to the communication interface 3a3. The processing unit 3a1 may be a CPU (Central Processing Unit). The memory unit 3a2 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 3a3 may communicate with the plasma processing device 1 via a communication line such as a LAN (Local Area Network). Furthermore, the storage medium may be temporary or permanent.

[0017] <Plasma Processing Equipment> Next, as an example of the plasma processing apparatus 1 described above, an example of the configuration of a capacitively coupled plasma processing apparatus 1 will be explained. Figure 2 is a longitudinal cross-sectional view showing a schematic of the configuration of the plasma processing apparatus 1. Figure 3 is a partially enlarged view showing an enlarged part of the configuration of the substrate support section 11 shown in Figure 2.

[0018] 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 portion 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 is grounded. The shower head 13 and the substrate support unit 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0019] The substrate support section 11 includes a main body 110, a ring assembly 120, and a lifter 130. The main body 110 has a central region 110a for supporting the substrate W and an annular region 110b for supporting the ring assembly 120. In plan view, the annular region 110b of the main body 110 surrounds the central region 110a of the main body 110. The substrate W is placed on the central region 110a of the main body 110, and the ring assembly 120 is placed on the annular region 110b of the main body 110 so as to surround the substrate W on the central region 110a of the main body 110. Therefore, the central region 110a is also called the substrate support surface for supporting the substrate W, and the annular region 110b is also called the ring support surface for supporting the ring assembly 120.

[0020] As shown in Figure 3, in one embodiment, the main body 110 includes a base 111, an electrostatic chuck 112, a support 113, and an insulator 114.

[0021] The base 111 includes a conductive member. The conductive member of the base 111 can function as a lower electrode. The electrostatic chuck 112 is placed on the base 111. The electrostatic chuck 112 includes a ceramic member 112a and an electrostatic electrode 112b placed within the ceramic member 112a. The ceramic member 112a has a central region 110a. In one embodiment, the ceramic member 112a and the support 113 have an annular region 110b. Alternatively, instead of an annular insulating member such as the support 113, another member surrounding the electrostatic chuck 112, such as an annular electrostatic chuck, may have the annular region 110b. The ring assembly 120 may be placed on the annular electrostatic chuck or the annular insulating member, or it may be placed on both the electrostatic chuck 112 and the annular insulating member as shown in the figure. Alternatively, the configuration of the annular electrostatic chuck and the annular insulating member may be omitted, and the ring assembly 120 may be placed only on the electrostatic chuck 112.

[0022] Furthermore, at least one RF / DC electrode, which will be coupled to the RF power supply 31 and / or DC power supply 32 described later, may be placed within the ceramic member 112a. In this case, at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or DC signal, described later, is supplied to at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 111 and at least one RF / DC electrode may function as multiple lower electrodes. Also, the electrostatic electrode 112b may function as a lower electrode. Therefore, the substrate support portion 11 includes at least one lower electrode.

[0023] The support 113 is a member formed in an annular shape in plan view using an insulating material such as quartz, and supports the base 111 and the electrostatic chuck 112. In one embodiment, the ring assembly 120 is placed on the support 113 as described above. The support 113 also has a plurality of through holes 113a, three in this embodiment, that penetrate in the thickness direction. As shown in Figure 3, the lift pins 131 of the lifter 130, which will be described later, are inserted through the through holes 113a.

[0024] The insulator 114 is a cylindrical member made of ceramic or the like, and supports the support 113. The insulator 114 is formed to have an outer diameter equivalent to the outer diameter of the support 113, and supports the peripheral edge of the support 113.

[0025] The ring assembly 120, as an annular member, includes multiple annular members. As shown in Figure 3 as an example, the ring assembly 120 includes an insulating ring 121, an outer edge ring 122, and an inner edge ring 123 as multiple annular members. The outer edge ring 122 and the inner edge ring 123 are formed from materials such as silicon, silicon carbide, or quartz, for example. The insulating ring 121 is supported by a support 113 that constitutes the annular region 11b (ring support surface). The inner edge ring 123 is supported by an electrostatic chuck 112 and an insulating ring 121 that constitute the annular region 110b (ring support surface). That is, the insulating ring 121 and the inner edge ring 123 are stacked and supported in this order on the support 113 that constitutes the annular region 11b (ring support surface). Furthermore, the ring assembly 120 is lifted up from the annular region 110b (ring support surface) by the operation of a lifter 130, thereby enabling transfer to and from a transport device 2 located outside the plasma processing apparatus 1. Furthermore, the inner edge ring 123 described above may constitute a "conductive ring" according to the technology of this disclosure. Also, the outer edge ring 122 described above may constitute an "additional conductive ring" according to the technology of this disclosure. In other words, the ring assembly 120 as an annular member includes an insulating ring 121, an additional conductive ring 122, and a conductive ring 123 as a plurality of annular members.

[0026] The outer edge ring 122 is formed to be larger in the thickness direction compared to the insulating ring 121, and is positioned to surround the inner edge ring 123 and the insulating ring 121, while the inner portion of the outer edge ring 122 is positioned to overlap the outer portion of the insulating ring 121 in the vertical direction. In other words, the upper surface of the insulating ring 121 constitutes the support surface for the outer edge ring 122 and the inner edge ring 123.

[0027] The configuration of the ring assembly 120 is not limited to the illustrated example; for example, the insulating ring 121 and the outer edge ring 122 may be integrally formed. In this case, the insulating ring 121 and the outer edge ring 122 may be made of the same material; that is, the outer edge ring 122 may function as part of the insulating ring, or the insulating ring 121 may function as part of an additional conductive ring.

[0028] Furthermore, as shown in Figures 4A and 4B, the insulating ring 121 has multiple through holes 121a that penetrate in the thickness direction, with three through holes 121a in this embodiment. The through holes 121a are formed at positions corresponding to the through holes 113a formed in the support 113, and the upper support portion 131a of the lift pin 131, which will be described later, is inserted through them, as shown in Figure 3.

[0029] The three through holes 121a have an upper hole portion 121a1 and a lower hole portion 121a2. The upper hole portion 121a1 of the through hole 121a has a substantially rectangular shape in which the first width W1 extending in the radial direction R1 of the insulating ring 121 is larger than the second width W2 extending in the circumferential direction C1 of the insulating ring 121 which is perpendicular to the radial direction R1. The first width W1 is formed to be larger than at least the diameter of the upper support portion 131a of the lift pin 131 (the fifth width W5 described later). The second width W2 is formed to be larger than the diameter of the upper support portion 131a (the fifth width W5) and smaller than the diameter of the lower support portion 131b of the lift pin 131 (the sixth width W6 described later). The lower hole portion 121a2 of the insulating ring 121 has a flared shape (inclined surface 1211a) in which the first width W1 and second width W2 of the upper hole portion 121a1 widen downwards (towards the bottom surface of the insulating ring 121). It is desirable that the lower end of the inclined surface 1211a of the lower hole portion 121a2 be formed to be at least larger than the conveying accuracy of the ring assembly 120 by the conveying device 2. In the insulating ring 121 according to this embodiment, the upper support portion 131a of the lift pin 131 is inserted into the upper hole portion 121a1, and the lower support portion 131b of the lift pin 131 makes two-point contact with the inclined surface 1211a of the lower hole portion 121a2 on the circumferential C1 side (second width W2 side).

[0030] As described above, in the upper hole portion 121a1, the first width W1 extending in the radial direction R1 is formed to be larger than the second width W2 extending in the circumferential direction C1. However, it is desirable that the sizes of the first width W1 and the second width W2 be as similar as possible. In other words, it is desirable that the upper hole portion 121a1 has a substantially square shape in plan view.

[0031] The inner edge ring 123, which acts as a conductive ring, is sometimes called a focus ring and improves the in-plane uniformity of plasma treatment on the substrate W. In addition, the outer edge ring 122, which acts as an additional conductive ring, substantially expands the area of ​​the conductive portion (inner edge ring 123) in a plan view on the substrate support portion 11. The inner edge ring 123 and the outer edge ring 122 can be formed from silicon, silicon carbide, quartz, or the like, as described above.

[0032] As shown in Figures 5A and 5B, multiple grooves, specifically three in this embodiment, are formed on the bottom surface of the inner edge ring 123. The grooves 123a are formed at positions corresponding to the through holes 121a formed in the insulating ring 121, and the tip of the upper support portion 131a of the lift pin 131, which is inserted through the through holes 121a, contacts the bottom surface 123a1.

[0033] As shown in Figure 5B, the three grooves 123a have a substantially elongated shape, in which the third width W3 extending in the radial direction R2 of the inner edge ring 123 at the bottom surface 123a1 is larger than the fourth width W4 extending in the circumferential direction C2 of the inner edge ring 123 which is perpendicular to the radial direction R2. The third width W3 is formed to be larger than the diameter of the upper support portion 131a (the fifth width W5). The fourth width W4 is formed to be approximately the same size as the diameter of the upper support portion 131a of the lift pin 131 (the fifth width W5, which will be described later). Furthermore, the bottom surfaces 123a1 of the three grooves 123a have a shape that fits with the tip shape of the upper support portion 131a of the lift pin 131, particularly in the direction of extension of the fourth width W4. Specifically, in this embodiment, as will be described later, the upper support portion 131a has a hemispherical shape 131a1 with a protruding tip, but the bottom surface 123a1 of the groove 123a is formed as a concave shape having approximately the same curvature as the hemispherical shape 131a1 (hereinafter, the bottom surface 123a1 having a curved shape may be referred to as "curved bottom surface 123a1'"). The flared sides 123a2 of the three grooves 123a are formed with inclined portions such that the third width W3 and fourth width W4 of the bottom surface 123a1 widen downwards (towards the bottom surface of the inner edge ring 123). It is desirable that the lower end of the inclined portion of the groove 123a be formed to be at least larger than the conveying accuracy of the inner edge ring 123 by the conveying device 2. In the inner edge ring 123 according to this embodiment, the upper support portion 131a of the lift pin 131 makes line contact with the bottom surface 123a1 in the circumferential direction (fourth width W4 direction) of the inner edge ring 123.

[0034] The depth of groove 123a is, for example, 0.4 mm to 1.0 mm.

[0035] In one embodiment, the lifter 130 includes a plurality of lift pins 131, in this embodiment corresponding to the through-hole 121a of the insulating ring 121 and the groove 123a of the inner edge ring 123, and at least one actuator 132. The lift pins 131 also include a plurality of cylindrical support portions of different diameters. As shown as an example in Figure 3, the lift pins 131 include an upper support portion 131a and a lower support portion 131b. The upper support portion 131a and the lower support portion 131b may be constructed as a single unit.

[0036] The upper support portion 131a has a fifth width W5 that is smaller in diameter than at least the first width W1 and second width W2 of the through hole 121a formed in the insulating ring 121. The fifth width W5 is approximately the same size as the fourth width W4 of the groove 123a formed in the inner edge ring 123. The upper support portion 131a is axially connected to the upper surface of the lower support portion 131b, which will be described later, and moves vertically (axially) together with the lower support portion 131b by the operation of the actuator 132. The upper support portion 131a is configured to be able to protrude from and retract from the upper surface of the insulating ring 121 via the through hole 121a, thereby supporting the lower surface of the inner edge ring 123, which is supported on the upper surface of the insulating ring 121, more specifically the bottom surface 123a1 of the groove 123a formed in the inner edge ring 123, and moving vertically (lifting up).

[0037] Furthermore, the tip of the upper support portion 131a is formed in a hemispherical shape 131a1 that gradually tapers upward (see Figure 5B). This hemispherical shape 131a1 has approximately the same curvature as the concave surface of the curved bottom surface 123a1' of the groove 123a formed in the inner edge ring 123. As a result, the tip of the upper support portion 131a is configured to be able to make line contact with the groove 123a formed in the inner edge ring 123.

[0038] The lower support portion 131b has a diameter larger than at least the second width W2 of the through hole 121a formed in the insulating ring 121 (the sixth width W6 in Figure 3). That is, the lower support portion 131b has a stepped portion on its upper surface that protrudes radially outward from the outer circumference of the upper support portion 131a. The lower support portion 131b is configured to support the inclined surface 1211a formed in the lower hole portion 121a2 of the through hole 121a by the stepped portion, thereby supporting the lower surface of the insulating ring 121 and moving it vertically (lifting it up). At the same time, the outer edge ring 122 held on the insulating ring 121 is also moved vertically (lifted up).

[0039] The actuator 132 moves the lift pin 131 along the vertical (axial) direction, raising and lowering the ring assembly 120 (insulating ring 121, outer edge ring 122, and inner edge ring 123) above the annular region 110b (ring support surface). This facilitates the transfer of the ring assembly 120 between the substrate support section 11 and the transport arm 2a of the transport device 2. Examples of actuators include electric actuators, air cylinders, motors, etc.

[0040] The number of actuators 132 arranged on the lifter 130 is not particularly limited. That is, for example, multiple lift pins 131 may be moved vertically as a single unit by one actuator 132. Alternatively, for example, multiple actuators 132 may be arranged corresponding to each lift pin 131, and each lift pin 131 may be moved vertically independently.

[0041] The substrate support section 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck 112, the ring assembly 120, and the substrate W to a target temperature. The temperature control module may include a heater, a heat transfer medium, a flow path 111a, or a combination thereof. A heat transfer fluid, such as brine or gas, flows through the flow path 111a. In one embodiment, the flow path 111a is formed within the base 111, and one or more heaters are arranged within the ceramic member 112a of the electrostatic chuck 112. The substrate support section 11 may also include a heat transfer gas supply section configured to supply a heat transfer gas (backside gas) to the gap between the back surface of the substrate W and the upper surface of the electrostatic chuck 112.

[0042] Let's return to the explanation of Figure 2. The showerhead 13 is configured to introduce at least one processing 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 a plurality of gas inlet ports 13c. The processing gas supplied from the gas supply unit 20 to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s through the plurality of gas inlet ports 13c. The showerhead 13 also includes at least one upper electrode. In addition to the showerhead 13, the gas introduction unit may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 10a.

[0043] 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 at least one flow modulation device that modulates or pulses the flow rate of at least one processing gas.

[0044] 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 the plasma generation unit 12. 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.

[0045] 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.

[0046] 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.

[0047] 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 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.

[0048] 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 a combination thereof pulse waveform. In one embodiment, a waveform generation unit for generating a sequence of voltage pulses from the 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 period. 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.

[0049] 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 internal pressure of the plasma processing space 10s. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0050] Although various exemplary embodiments have been described above, the invention is not limited to the exemplary embodiments described above, and various additions, omissions, substitutions, and modifications may be made. Furthermore, it is possible to combine elements from different embodiments to form other embodiments.

[0051] For example, in the above embodiment, as shown in Figure 3, the tip of the upper support portion 131a of the lift pin 131 is formed in a hemispherical shape 131a1. However, as shown in Figure 6A, the tip of the upper support portion 131a may have a substantially flat surface 131a2. In this case, in order to bring the tip of the upper support portion 131a and the bottom surface of the groove 123a into line contact, it is desirable that the bottom surface shape of the groove 123a also has a flat bottom surface 123a1'' that engages with the tip of the upper support portion 131a, instead of the curved bottom surface 123a1' described above. In this case, as shown in Figure 6B, each of the at least three grooves 123a of the conductive ring 123 may be defined by a flat bottom surface 123a1'', a vertical side surface 123a3 extending downward from the flat bottom surface 123a1'', and a flared side surface 123a2 spreading downward from the vertical side surface 123a3.

[0052] Furthermore, for example, in the above embodiment, the through hole 121a formed in the insulating ring 121 was formed in a substantially rectangular shape, preferably a substantially square shape. However, as shown in Figure 6C, the through hole 121a may be formed in a substantially elongated shape with large rounded corners. In this case, it is desirable that the substantially elongated through hole 121a has a first width W1 extending in the radial direction R1 of the insulating ring 121 that is larger than the second width W2 extending in the circumferential direction C1, that is, an elongated shape with a longitudinal direction in the radial direction R1 of the insulating ring 121.

[0053] <Effects, etc.> A plasma processing system according to one embodiment is configured as described above. That is, the plasma processing system according to one embodiment includes a plasma processing chamber 10, a substrate support portion 11, an insulating ring 121, a conductive ring 123, at least three lift pins 131, and at least one actuator 132. The substrate support portion 11 is located inside the plasma processing chamber 10 and has a substrate support surface 110a and a ring support surface 110b. The insulating ring 121 is located on the ring support surface 110b and has at least three through holes 121a. Each of the at least three through holes 121a has an upper hole portion 121a1 and a lower hole portion 121a2. The upper hole portion 121a1 has a first width W1 in the radial direction R1 of the insulating ring 121 and a second width W2 in the circumferential direction C1 of the insulating ring 121. The second width W2 is smaller than the first width W1, and the lower hole portion 121a2 has a flared shape that widens downward when viewed from the side. The conductive ring 123 is supported by the insulating ring 121 and has at least three grooves 123a on its lower surface, each corresponding to at least three through holes 121a. Each of the at least three grooves 123a has a third width W3 in the radial direction R2 of the conductive ring 123 and a fourth width W4 in the circumferential direction C2 of the conductive ring 123. The fourth width W4 is smaller than the third width W3. At least three lift pins 131 are positioned below the ring support surface 110b and correspond to each of the at least three grooves 123a. Each of the at least three lift pins 131 has an upper support portion 131a and a lower support portion 131b. The upper support portion 131a is configured to support the conductive ring 123 from below by contacting the bottom surface 123a1 of the groove 123a of the conductive ring 123 through the through hole 121a of the insulating ring 121. The lower support portion 131b is configured to support the insulating ring 121 from below by contacting the inclined surface 1211a of the insulating ring 121 that defines the lower hole portion 121a2. At least one actuator 132 is configured to move at least three lift pins 131 in the vertical direction.The lower support portion 131b of the lift pin 131 is configured to contact the inclined surface 1211a at two points in the radial direction R1 of the insulating ring 121, without contacting the inclined surface 1211a in the circumferential direction C1 of the insulating ring 121.

[0054] In one embodiment, each of the at least three through holes 121a of the insulating ring 121 has a rectangular shape when viewed from above. In one embodiment, the upper support portion 131a has a cylindrical shape having a first diameter W5 smaller than a second width W2, and the lower support portion 131b has a cylindrical shape having a second diameter W6 larger than the second width W2. In one embodiment, the tip of the upper support portion 131a of the lift pin 131 has a hemispherical shape 131a1. In one embodiment, the tip of the upper support portion 131a of the lift pin 131 has a flat surface 131a2. In one embodiment, each of the at least three grooves 123a of the conductive ring 123 is defined by a flat bottom surface 123a1'', a vertical side surface 123a3 extending downward from the flat bottom surface 123a1'', and a flared side surface 123a2 widening downward from the vertical side surface 123a3. In one embodiment, each of the at least three grooves 123a of the conductive ring 123 is defined by a curved bottom surface 123a1'. In one embodiment, each of the at least three grooves 123a of the conductive ring 123 is defined by a flat bottom surface 123a1'' and a flared side surface 123a2 that extends downward from the flat bottom surface 123a1''. In one embodiment, the plasma processing system 1 further includes an additional conductive ring 122 positioned to surround the conductive ring 123 and the insulating ring 121. At least a portion of the additional conductive ring 122 longitudinally overlaps with the outer portion of the insulating ring 121.

[0055] Furthermore, a plasma processing system 1 according to one embodiment includes a plasma processing chamber 10, a substrate support portion 11, a first annular member 121, a second annular member 123, at least three lift pins 131, and at least one actuator 132. The substrate support portion 11 is disposed within the plasma processing chamber 10 and has a substrate support surface 110a and a ring support surface 110b. The first annular member 121 is disposed on the ring support surface 110b and has at least three through holes 121a. Each of the at least three through holes 121a has an upper hole portion 121a1 and a lower hole portion 121a2. The upper hole portion 121a1 has a first width W1 in a first direction R1 and a second width W2 in a second direction C1 perpendicular to the first direction R1. The second width W2 is smaller than the first width W1. The lower hole portion 121a2 has a flared shape 1211a that widens downward when viewed from the side. The second annular member 123 is supported by the first annular member 121 and has at least three grooves 123a on its lower surface, corresponding to each of the at least three through holes 121a. Each of the at least three grooves 123a has a third width W3 in a third direction R2 and a fourth width W4 in a fourth direction C2 perpendicular to the third direction R2. The fourth width W4 is smaller than the third width W3. At least three lift pins 131 are positioned below the ring support surface 110b and correspond to each of the at least three grooves 123a. Each of the at least three lift pins 131 has an upper support portion 131a and a lower support portion 131b. The upper support portion 131a is configured to support the second annular member 123 from below by contacting the bottom surface 123a1 of the groove 123a of the second annular member 123 through the through hole 121a of the first annular member 121. The lower support portion 131b is configured to support the first annular member 121 from below by contacting the inclined surface 1211a of the first annular member 121 that defines the lower hole portion 121a2. At least one actuator 132 is configured to move at least three lift pins 131 in the longitudinal direction.

[0056] In the plasma processing system, a substrate W is transported into the plasma processing apparatus 1 using a transport device 2, and after performing a desired plasma treatment such as etching on the transported substrate W, the substrate W is transported out of the plasma processing apparatus 1 using the transport device 2. In this embodiment, the inner edge ring 123 and the outer edge ring 122 are made of a conductive material. Therefore, during plasma processing in the plasma processing system, a sheath is formed above the ring assembly 120, more specifically, above the inner edge ring 123 as a conductive ring and the outer edge ring 122 as an additional conductive ring. This makes it possible to obtain good and uniform plasma processing results in both the central and peripheral portions of the substrate W held by the substrate support portion 11.

[0057] As mentioned above, recent plasma processing systems require improved installation accuracy of the ring assembly 120 relative to the substrate support section 11. Patent Document 1 discloses that, in order to improve the installation accuracy of the annular member, grooves formed in the edge ring and through holes formed in the covering ring are made larger than the transport accuracy of the annular member by the transport mechanism. However, in this case, if a misalignment occurs between the lifter and the groove (through hole) due to the effects of machine error (e.g., machining tolerance) or thermal expansion of the annular member, the positioning accuracy of the annular member may deteriorate.

[0058] In this regard, according to the plasma processing apparatus 1 of the present disclosure, a through hole 121a is formed in the insulating ring 121 corresponding to the covering ring, with a substantially rectangular shape in which the first width W1 is larger than the second width W2, and a groove 123a is formed in the inner edge ring 123, with a substantially elongated hole shape in which the third width W3 is larger than the fourth width W4. As a result, even if a misalignment occurs between the position of the lift pin 131 and the position of the through hole 121a (groove 123a) due to the effects of the machining tolerances mentioned above, the insulating ring 121 can slide around the lift pin 131 as an axis, that is, it becomes free in the longitudinal direction of the through hole 121a (groove 123a), so the insulating ring 121 can be properly guided to the desired position. At the same time, since the outer edge ring 122, which acts as an additional conductive ring, is held on the upper surface of the insulating ring 121, the position of the outer edge ring 122 is also corrected simultaneously.

[0059] Furthermore, as described above, the lower support portion 131b of the lift pin 131 makes two-point contact with the inclined portion of the lower hole portion 121a2 of the through hole 121a. Therefore, compared to cases where the lower support portion 131b and the inclined portion of the lower hole portion 121a2 make contact at three or more points in the circumferential direction, or where there is line contact or surface contact, the insulating ring 121 slides more easily, and the misalignment of the insulating ring 121 (ring assembly 120) can be corrected more appropriately.

[0060] At this time, as described above, the upper support portion 131a of the lift pin 131 makes line contact with the bottom surface 123a1 of the groove 123a. When the upper support portion 131a and the bottom surface 123a1 of the groove 123a are in contact at only one or two points, the upper support portion 131a and the bottom surface 123a1 slide relatively easily, making it easy to correct the misalignment of the inner edge ring 123. On the other hand, because they slide easily, the inner edge ring 123 is more likely to shift position when the lift pin 131 moves in the vertical direction. On the other hand, when the upper support portion 131a and the bottom surface 123a1 of the groove 123a are in surface contact, relative sliding between the bottom surface 123a1 and the upper support portion 131a can be suppressed. However, because sliding is suppressed, it becomes difficult to correct the misalignment of the inner edge ring 123. In this respect, in the above embodiment, the upper support portion 131a of the lift pin 131 makes line contact with the bottom surface 123a1 of the groove 123a. Therefore, the bottom surface 123a1 can slide against the upper support portion 131a to appropriately correct the misalignment of the inner edge ring 123, and the misalignment of the inner edge ring 123 when the lift pin 131 moves in the vertical direction can also be appropriately suppressed.

[0061] Furthermore, if the insulating ring 121 has a through hole 121a with a roughly rectangular shape in which the first width W1 is larger than the second width W2, as described above, the insulating ring 121 will slide in the longitudinal direction of the through hole 121a, which may cause the insulating ring 121 to shift position when the lift pin 131 moves in the vertical direction. In light of these points, in order to suppress misalignment of the insulating ring 121 (improve the positional accuracy of the insulating ring 121), it is desirable that the through hole 121a be formed in a substantially square shape as described above. At this time, it is also desirable that the longitudinal width of the through hole 121a (second width W2) be set to a size such that the lower support portion 131b of the lift pin 131 makes contact with the inclined portion of the through hole 121a at two points. This allows for correction of the misalignment of the insulating ring 121 by making contact at least two points between the lower support portion 131b and the inclined portion, and also reduces the free width of the lift pin 131 in the longitudinal direction of the through hole 121a, thereby suppressing misalignment of the insulating ring 121 when the lift pin 131 moves in the vertical direction.

[0062] <How to replace the ring assembly> Next, the replacement process for the ring assembly 120 configured as described above will be explained with reference to the drawings. The following process is performed under the control of the control unit 3 as an example.

[0063] (Step St1: Transfer and removal of inner edge ring 123) First, the worn inner edge ring 123 to be replaced is transferred from the substrate support section 11 to the transport device 2.

[0064] Specifically, first the lifter 130 is raised, and as shown in Figure 7, the inner edge ring 123 is passed from the upper surface of the insulating ring 121 to the upper support portion 131a of the lifter 130, passing through the through hole 113a of the support body 113 and the through hole 121a of the insulating ring 121. At this time, the lifter 130 is raised to the extent that the insulating ring 121 is not passed to the lower support portion 131b, and is raised until the tip of the upper support portion 131a reaches a desired height H1. The desired height H1 here is the height of the upper support portion 131a of the lifter 130, with reference to the upper surface of the outer edge ring 122 held by the insulating ring 121 placed on the support body 113. Furthermore, the desired height H1 is such that when the transport arm 2a is inserted into and removed from the space between the outer edge ring 122 on the insulating ring 121 placed on the support 113 and the inner edge ring 123 supported by the upper support portion 131a, the transport arm 2a does not interfere with the outer edge ring 122 and the inner edge ring 123, etc.

[0065] Next, the inner edge ring 123 is removed from the plasma processing chamber 10 of the plasma processing apparatus 1.

[0066] Specifically, a transport arm 2a is inserted into the depressurized plasma processing chamber 10 via an inlet / outlet (not shown). The transport arm 2a is then moved between the outer edge ring 122 on the insulating ring 121 placed on the support 113 and the inner edge ring 123 supported by the upper support portion 131a of the lifter 130.

[0067] Next, the lifter 130 is lowered, and the inner edge ring 123 is transferred from the upper support portion 131a of the lifter 130 to the transfer arm 2a. Subsequently, the transfer arm 2a is withdrawn from the plasma processing chamber 10, and the inner edge ring 123 is transported out of the plasma processing apparatus 1. The transported inner edge ring 123 is then transported into a storage module (not shown) as an example.

[0068] (Step St2: Transfer and removal of the insulating ring 121 and the outer edge ring 122) Once the inner edge ring 123 is removed from the plasma processing apparatus 1, the worn-out insulating ring 121 and outer edge ring 122, which are to be replaced, are then transferred from the substrate support section 11 to the transport device 2.

[0069] Specifically, first the lifter 130 is raised, and as shown in Figure 8, the insulating ring 121 is passed from the upper surface of the annular region 110b (ring support surface) of the substrate support portion 11 to the lower support portion 131b of the lifter 130, which has passed through the through hole 113a of the support body 113. At this time, since the outer edge ring 122 is held on the insulating ring 121, the outer edge ring 122 is also passed to the lower support portion 131b via the insulating ring 121. During this process, the lifter 130 is raised until the stepped portion of the lower support portion 131b reaches a desired height H2. The desired height H2 here is the height of the lower support portion 131b of the lifter 130, with respect to the upper surface of the substrate support portion 11 (more specifically, the upper surface of the electrostatic chuck 112). Furthermore, the desired height H2 is such that when the transport arm 2a is inserted into and removed from the space between the electrostatic chuck 112 and the insulating ring 121 supported by the lower support portion 131b, the transport arm 2a does not interfere with the insulating ring 121 and the electrostatic chuck 112, etc.

[0070] Next, the insulating ring 121 and the outer edge ring 122 are removed from the plasma processing chamber 10 of the plasma processing apparatus 1.

[0071] Specifically, a transport arm 2a is inserted into the depressurized plasma processing chamber 10 via an inlet / outlet (not shown). Then, the transport arm 2a is moved between the electrostatic chuck 112 and the insulating ring 121 supported by the lower support portion 131b of the lifter 130.

[0072] Next, the lifter 130 is lowered, and the insulating ring 121 and the outer edge ring 122 are transferred from the lower support portion 131b of the lifter 130 to the transfer arm 2a. Subsequently, the transfer arm 2a is withdrawn from the plasma processing chamber 10, and the insulating ring 121 and the outer edge ring 122 are transported out of the plasma processing apparatus 1. The transported insulating ring 121 and the outer edge ring 122 are transported into a storage module (not shown) as an example.

[0073] (Step St3: Loading and placing the ring assembly 120) Once the inner edge ring 123, insulating ring 121, and outer edge ring 122 are removed from the plasma processing apparatus 1, a new ring assembly 120 (insulating ring 121, outer edge ring 122, and inner edge ring 123) to be replaced is then brought into the plasma processing apparatus 1.

[0074] Specifically, a transport arm 2a of the transport device 2, which holds an insulating ring 121 and a new ring assembly 120 including an outer edge ring 122 and an inner edge ring 123 held on the insulating ring 121, is inserted into the plasma processing chamber 10 via an inlet / outlet (not shown). At this time, the plasma processing chamber 10 may be under reduced pressure. Then, as shown in Figure 9, the new ring assembly 120 is transported by the transport arm 2a above the annular region 110b of the substrate support portion 11.

[0075] Next, the new ring assembly 120 is placed from the transport device 2 onto the annular region 110b of the substrate support section 11.

[0076] Specifically, the lifter 130 is raised, and as shown in Figure 10A, the inner edge ring 123 is transferred from the upper surface of the insulating ring 121 held by the transport arm 2a to the upper support portion 131a of the lifter 130, which has passed through the through hole 121a of the insulating ring 121. At this time, the through hole 121a of the insulating ring 121 and the groove 123a of the inner edge ring 123 are formed such that the lower end of the inclined portion is at least larger than the transport accuracy of the inner edge ring 123 by the transport device 2, as described above. Therefore, even if there is a misalignment between the lift pin 131 and the through hole 121a and groove 123a due to the transport accuracy of the transport device 2, the lift pin 131 can be properly inserted into the through hole 121a and further guided to the bottom surface 123a1 of the groove 123a.

[0077] Next, the lifter 130 continues to rise, and as shown in Figure 10B, the insulating ring 121 is transferred from the transport arm 2a to the lower support portion 131b of the lifter 130. At this time, the outer edge ring 122 on the insulating ring 121 is also transferred to the lower support portion 131b. During this process, the lifter 130 continues to rise until the stepped portion of the lower support portion 131b reaches the desired height H2. In this embodiment, the through hole 121a of the insulating ring 121 and the groove 123a of the inner edge ring 123 are formed with a radial width (first width W1 or third width W3) that is larger than the circumferential width (second width W2 or fourth width W4). Therefore, even if a misalignment occurs between the lift pin 131 and the through hole 121a due to machining tolerances or the like, the lift pin 131 can be properly inserted into the through hole 121a and further guided to the bottom surface 123a1 of the groove 123a. At this time, the lower support portion 131b of the lift pin 131 makes two-point contact with the inclined portion of the through hole 121a, thereby allowing the insulating ring 121 to move freely with respect to the longitudinal direction of the through hole 121a, with the lift pin 131 as its axis. Therefore, even if there is a misalignment between the lift pin 131, the through hole 121a, and the groove 123a due to the various factors described above, the insulating ring 121 slides with respect to the longitudinal direction of the through hole 121a, allowing the insulating ring 121 and the outer edge ring 122 to be appropriately positioned to the desired location. Similarly, the upper support portion 131a of the lift pin 131 makes line contact with the bottom surface 123a1 of the groove 123a, thereby allowing the inner edge ring 123 to be properly positioned to the desired location and suppressing displacement of the inner edge ring 123 when the ring assembly 120 is subsequently placed on top of it.

[0078] Next, the transport arm 2a is withdrawn from the plasma processing chamber 10. The lifter 130 is also lowered. As a result, the insulating ring 121, the outer edge ring 122, and the inner edge ring 123 are placed on the upper surface of the annular region 110b of the substrate support 11 and the upper surface of the support body 113. Specifically, first the insulating ring 121 and the outer edge ring 122 are placed on the upper surface of the support body 113, and then the inner edge ring 123 is placed on the upper surface of the insulating ring 121 and the upper surface of the annular region 110b of the substrate support 11. In this way, the series of processes for placing the ring assembly 120 on the substrate support portion 11 is completed.

[0079] In the above embodiment, the insulating ring 121, outer edge ring 122, and inner edge ring 123, which constitute the ring assembly 120, were loaded and placed simultaneously. However, the loading and placement of any one of these insulating rings 121, outer edge ring 122, or inner edge ring 123 may be carried out independently. Furthermore, in the above embodiment, the insulating ring 121, outer edge ring 122, and inner edge ring 123, which constitute the ring assembly 120, were transferred and unloaded sequentially. However, the transfer and unloading of any one of these insulating rings 121, outer edge ring 122, or inner edge ring 123 may be performed simultaneously. In this case, the inner edge ring 123 may be transferred between the lift pin 131 and the transport arm 2a and unloaded from the plasma processing apparatus 1 while placed on the insulating ring 121, that is, integrally with the insulating ring 121.

[0080] <Variations of edge ringing> Figures 11A to 11C show examples of the configuration of the inner edge ring 223 according to another embodiment. In the inner edge ring 223 according to other embodiments, of the multiple grooves 223a to 223c formed on the bottom surface, at least one groove (groove 223a in the illustrated example) may be formed in a circular shape (Figure 11B), and the remaining grooves (grooves 223b and 223c in the illustrated example) may be formed in an elongated hole shape (Figure 11C).

[0081] In one embodiment, the circular groove 223a has a diameter (first diameter D1 in Figure 11) at its bottom surface 223a1 that is approximately the same as the width (fifth width W5) of the upper support portion 131a of the lift pin 131. Furthermore, the bottom surface 223a1 of the groove 223a has a shape that fits with the shape of the tip of the upper support portion 131a of the lift pin 131. In other words, the tip of the upper support portion 131a is configured to be able to make surface contact with the bottom surface 223a1 of the groove 223a formed in the inner edge ring 223. Furthermore, the side surface 223a2 of the groove 223a is formed with an inclined portion (flared shape) such that the first diameter D1 of the bottom surface 223a1 widens downward (towards the bottom surface of the inner edge ring 223). It is desirable that the lower end of the inclined portion of the groove 223a be formed to be at least larger than the conveying accuracy of the inner edge ring 223 by the conveying device 2.

[0082] In one embodiment, grooves 223b and 223c, which have an elongated hole shape, have the same structure as groove 123a of the inner edge ring 123 shown in the above embodiment. That is, grooves 223b and 223c are formed such that the third width W3 extending radially to the inner edge ring 223 is larger than the fourth width W4 extending circumferentially to the inner edge ring 223 which is perpendicular to the radial direction, and the bottom surfaces 223b1 and 223c1 have a shape that fits with the tip shape of the upper support portion 131a of the lift pin 131, particularly with respect to the extension direction of the fourth width W4. Furthermore, inclined portions are formed on the side surfaces 223b2 and 223c2 of grooves 223b and 223c. It is desirable that the lower end of the inclined portion of groove 123a be formed to be at least larger than the transport accuracy of the inner edge ring 123 by the transport device 2.

[0083] As shown in the above embodiment, if all three grooves 123a formed on the bottom surface of the inner edge ring 123 have an elongated hole shape, the inner edge ring 123 becomes free with respect to the longitudinal direction of the grooves 123a, as described above. This may cause the inner edge ring 123 to slide and become misaligned. Therefore, in the inner edge ring 223 according to another embodiment, at least one groove 223a is formed in a circular shape, and the inner edge ring 223 is positioned using the circular groove 223a as a base point. That is, the plasma processing system according to one embodiment includes a plasma processing chamber 10, a substrate support part 11, an annular member 223, at least three cylindrical lift pins 131, and at least one actuator 132. The substrate support part 11 is arranged inside the plasma processing chamber 10 and has a substrate support surface 110a and a ring support surface 110b. The annular member 223 is arranged on the ring support surface 110b and has at least three grooves 223a to 223c on its lower surface. Of the at least three grooves 223a to 223c, the first groove 223a has a circular bottom surface 223a1 when viewed from above. Of the at least three grooves 223a to 223c, the second groove 223b and the third groove 223c have bottom surfaces 223b1 and 223c1 having a first width W3 in the radial direction R3 of the annular member 223 and a second width W4 in the circumferential direction C3 of the annular member 223. The second width W4 is smaller than the first width W3. At least three cylindrical lift pins 131 are positioned below the ring support surface 110b and correspond to each of the at least three grooves 223a to 223c. Each of the at least three cylindrical lift pins 131 is configured to support the annular member 223 from below by contacting the bottom surfaces of the grooves 223a to 223c of the annular member 223. At least one actuator 132 is configured to move at least three cylindrical lift pins 131 in the longitudinal direction. As a result, the tip of the upper support portion 131a, which is formed to be approximately the same size, and the bottom surface 223a1 of the groove 223a engage and make surface contact, thereby suppressing sliding of the inner edge ring 223 and the lifter 130, at least in the horizontal direction. Furthermore, since the remaining grooves 223b and 223c are formed in an elongated hole shape, even if there is a misalignment between the grooves 223b and 223c and the lift pin 131 due to the various factors mentioned above, this misalignment can be corrected to appropriately guide the lift pin 131 into the grooves 223b and 223c, and the inner edge ring 223 can be positioned to the desired location.

[0084] In the above embodiment, of the at least three grooves 223a to 223c, one groove 223a is formed in a circular shape, and the remaining grooves 223b and 223c are formed in an elongated hole shape. However, if, for example, the inner edge ring 223 can be properly positioned, each of the at least three grooves 223a to 223c may be formed in a circular shape. In other words, in one embodiment, each of the at least three grooves 223a to 223c of the conductive ring 123 is defined by a bottom surface 223a1 having a shape that can fit with the tip of the upper support portion 131a of the lift pin 131, and a flared side surface 223a2 that widens downward from the bottom surface.

[0085] <Modified example of groove formed in the inner edge ring> The cross-sectional shape of the elongated grooves formed in the inner edge ring (groove 123a of inner edge ring 123, grooves 223b and 223c of inner edge ring 223) is not limited to the above embodiment. For example, as shown in Figure 12A, the groove 123a may have a flat bottom surface 123a1'' having a substantially flat surface, a vertical side surface 123a3 as a vertical wall extending vertically downward from the flat bottom surface 123a1'', and a flared side surface 123a2 as a widening wall that spreads downward from the vertical side surface 123a3. In this case, it is desirable that the fourth width W4 in the short direction of the groove 123a (width of the vertical side surface 123a3 portion) be formed to be slightly larger than the diameter of the upper support portion 131a (fifth width W5) in order to allow sliding with respect to the lift pin 131. In this case, the contact method between the upper support portion 131a and the groove 123a is one-point contact. For example, as shown in Figure 12B, the groove 123a may be formed by a curved surface having a greater curvature than the tip of the hemispherical lift pin 131 (hemispherical shape 131a1). In other words, the groove 123a may have only a curved bottom surface 123a1' and may not have a vertical side surface 123a3 and a flared side surface 123a2. In this case, the groove 123a is configured to slide relative to the lift pin 131. In this case, the contact method between the upper support portion 131a and the groove 123a is a single-point contact. For example, as shown in Figure 12C, the groove 123a may have a flat bottom surface 123a1'' having a substantially flat surface, and a flared side surface 123a2 that widens downward from the flat bottom surface 123a1'' as a widening wall. In other words, compared to the above embodiment, in the example shown in Figure 12C, the flat bottom surface 123a1'' is not formed in a shape that fits with the lift pin 131. In this case, the contact method between the upper support portion 131a and the groove 123a is a three-point contact.

[0086] Furthermore, in the examples shown in Figures 5 and 12A to 12C above, the flared side surface 123a2 that extends downward from the bottom surface 123a1 (or vertical side surface 123a3) of the groove 123a is made up of a side surface that is straight in side view and widens at a constant rate downward. However, the flared side surface 123a2 may also be made up of a side surface that is curved in side view. Specifically, the groove 123a may have a curved bottom surface 123a1' having a greater curvature than the tip of the hemispherical lift pin 131 (hemispherical shape 131a1), as shown as an example in Figure 12D, and a flared curved side surface 123a4 that widens downward from the curved bottom surface 123a1' and curves upward (opposite side from the lift pin 131). In this case, the contact method between the upper support portion 131a and the groove 123a is single-point contact.

[0087] The curvature of the flared curved side surface 123a4 is not particularly limited. In other words, a groove 123a is formed in the inner edge ring 123 of the plasma processing apparatus 1 according to the present disclosure, and the groove 123a consists of a bottom surface 123a1 and one or more side surfaces (side surfaces 123a2, 123a3, and 123a4) having any curvature value of "0" or greater. A curvature of "0" on a side surface means that the side surface is straight when viewed from the side (side surface 123a2). A curvature greater than "0" means that the side surface is curved when viewed from the side (side surface 123a4).

[0088] Thus, the groove 123a (grooves 223b, 223c) can be formed with any cross-sectional shape. In this case, the contact method between the upper support portion 131a and the groove 123a differs depending on the cross-sectional shape. From the viewpoint of facilitating the alignment of the upper support portion 131a and the groove 123a, it is preferable that the contact area between the upper support portion 131a and the groove 123a be small. On the other hand, from the viewpoint of improving the installation accuracy of the upper support portion 131a and the groove 123a, it is preferable that the contact area between the upper support portion 131a and the groove 123a be large. Thus, the cross-sectional shape of groove 123a (grooves 223b, 223c) can be appropriately designed depending on the purpose.

[0089] Furthermore, the cross-sectional shape of the circular groove formed in the inner edge ring (groove 223a of the inner edge ring 223) is not limited to the above embodiment. For example, as shown in Figure 13A, the groove 223a may have a flat bottom surface 223a1'' having a substantially flat surface, a vertical side surface 223a3 as a vertical wall extending vertically downward from the flat bottom surface 223a1'', and a flared side surface 223a2 as a widening wall that spreads downward from the vertical side surface 223a3. In this case, it is desirable that the first diameter D1 of the groove 223a (width of the vertical side surface 223a3 portion) be formed to be slightly larger than the diameter of the upper support portion 131a (fifth width W5) in order to properly contact the tip of the lift pin 131 with the flat bottom surface 223a1''. Also, in this case, the contact method between the upper support portion 131a and the groove 123a is single-point contact. For example, as shown in Figure 13B, the groove 223a may be formed by a curved surface having a greater curvature than the tip of the hemispherical lift pin 131. In other words, the groove 223a may have only a curved bottom surface 223a1' and may not have a flared side surface 223a2 and a vertical side surface 223a3. In this case, the contact method between the upper support portion 131a and the groove 223a is a single-point contact. For example, as shown in Figure 13C, the groove 223a may have a flat bottom surface 223a1'' having a substantially flat surface, and a flared side surface 223a2 that widens downward from the flat bottom surface 223a1'' as a widening wall. In other words, compared to the example shown in Figure 11, in the example shown in Figure 13C, the flat bottom surface 223a1'' is not formed in a shape that fits with the lift pin 131. In this case, the contact method between the upper support portion 131a and the groove 223a is a three-point contact. Although not shown in the illustration, the circular groove 223a may also have a flared side surface 123a2, similar to the example shown in Figure 12D, which is a curved side surface in side view. In other words, the circular groove 223a may have a flared curved side surface, which is not shown.

[0090] Although various exemplary embodiments have been described above, the invention is not limited to the exemplary embodiments described above, and various additions, omissions, substitutions, and modifications may be made. Furthermore, it is possible to combine elements from different embodiments to form other embodiments. [Explanation of symbols]

[0091] 1. Plasma processing equipment 10 Plasma processing chamber 11. Substrate support section 12 Plasma generation section 110b Circular region 121 Insulating Ring 121a Through hole 121a1 Upper hole part 121a2 Lower hole part 123 Inner edge ring 123a Groove 123a1 Bottom 131 Lift Pin 131a Upper support part 131b Lower support part 132 Actuators W1 First width W2 Second width W3 Third width W4 4th width

Claims

1. a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support having a substrate support surface and a ring support surface; an insulating ring disposed on the ring support surface and having at least three through holes, each of the at least three through holes having an upper hole portion and a lower hole portion, the upper hole portion having a first width in a radial direction of the insulating ring and a second width in a circumferential direction of the insulating ring, the second width being smaller than the first width, and the lower hole portion having a flared shape widening downward when viewed from the side; a conductive ring supported by the insulating ring and having at least three grooves on a lower surface corresponding to the at least three through holes, each of the at least three grooves having a third width in a radial direction of the conductive ring and a fourth width in a circumferential direction of the conductive ring, the fourth width being smaller than the third width; at least three lift pins disposed below the ring support surface and corresponding to each of the at least three grooves, each of the at least three lift pins having an upper support portion and a lower support portion, the upper support portion being configured to support the conductive ring from below by contacting a bottom surface of the groove of the conductive ring through the through hole of the insulating ring, and the lower support portion being configured to support the insulating ring from below by contacting an inclined surface of the insulating ring that defines the lower hole portion; and at least one actuator configured to vertically move the at least three lift pins.

2. 2 . The plasma processing apparatus of claim 1 , wherein the lower support portion of the lift pin is configured to contact the inclined surface at two points in a radial direction of the insulating ring without contacting the inclined surface in a circumferential direction of the insulating ring.

3. The plasma processing apparatus according to claim 1 , wherein each of the at least three through holes of the insulating ring has a rectangular shape when viewed from above.

4. 3. The plasma processing apparatus of claim 1, wherein the upper support portion has a cylindrical shape with a first diameter smaller than the second width, and the lower support portion has a cylindrical shape with a second diameter larger than the second width.

5. The plasma processing apparatus according to claim 1 , wherein a tip of the upper support portion of the lift pin has a hemispherical shape.

6. The plasma processing apparatus of claim 1 , wherein a tip of the upper support portion of the lift pin has a flat surface.

7. Each of the at least three grooves of the conductive ring comprises: A flat bottom surface; a vertical side surface extending downward from the flat bottom surface; 3. The plasma processing apparatus according to claim 1, wherein the vertical side surface is flared and extends downward from the vertical side surface.

8. The plasma processing apparatus of claim 1 or 2, wherein each of the at least three grooves in the conductive ring is defined by a curved bottom surface.

9. Each of the at least three grooves of the conductive ring comprises: A flat bottom surface; 3. The plasma processing apparatus of claim 1, wherein the plasma processing apparatus is defined by a flared side surface extending downward from the flat bottom surface.

10. Each of the at least three grooves of the conductive ring comprises: a bottom surface having a shape that can be fitted to a tip of the upper support portion of the lift pin; The plasma processing apparatus according to claim 1 , further comprising a flared side surface extending downward from the bottom surface.

11. 3. The plasma processing apparatus of claim 1, further comprising an additional conductive ring arranged to surround the conductive ring and the insulating ring, at least a portion of the additional conductive ring vertically overlapping an outer portion of the insulating ring.

12. a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support having a substrate support surface and a ring support surface; an annular member disposed on the ring support surface and having at least three grooves on a lower surface thereof, a first groove of the at least three grooves having a bottom surface that is circular when viewed from above, and a second groove and a third groove of the at least three grooves having bottom surfaces that have a first width in a radial direction of the annular member and a second width in a circumferential direction of the annular member, the second width being smaller than the first width; at least three cylindrical lift pins disposed below the ring support surface and corresponding to each of the at least three grooves, each of the at least three cylindrical lift pins configured to support the annular member from below by contacting a bottom surface of the groove in the annular member; and at least one actuator configured to vertically move the at least three cylindrical lift pins.

13. The plasma processing apparatus of claim 12 , wherein the tip of the cylindrical lift pin has a hemispherical shape.

14. The plasma processing apparatus of claim 12 , wherein a tip of the cylindrical lift pin has a flat surface.

15. Each of the at least three grooves in the annular member comprises: A flat bottom surface; a vertical side surface extending downward from the flat bottom surface; 14. The plasma processing apparatus of claim 12, wherein the plasma processing apparatus is defined by a flared side extending downward from the vertical side.

16. 14. The plasma processing apparatus of claim 12 or 13, wherein each of the at least three grooves in the annular member is defined by a curved bottom surface.

17. Each of the at least three grooves in the annular member comprises: A flat bottom surface; 15. The plasma processing apparatus according to claim 12, wherein the plasma processing apparatus is defined by: a flared side surface extending downward from the flat bottom surface.

18. Each of the at least three grooves in the annular member comprises: a bottom surface having a shape that can be fitted to the tip of the cylindrical lift pin; and a flared side surface extending downward from the bottom surface.

19. a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support having a substrate support surface and a ring support surface; a first annular member disposed on the ring support surface and having at least three through holes, each of the at least three through holes having an upper hole portion and a lower hole portion, the upper hole portion having a first width in a first direction and a second width in a second direction perpendicular to the first direction, the second width being smaller than the first width, and the lower hole portion having a flared shape widening downward when viewed from the side; a second annular member supported by the first annular member and having at least three grooves on a lower surface thereof corresponding to the at least three through holes, each of the at least three grooves having a third width in a third direction and a fourth width in a fourth direction perpendicular to the third direction, the fourth width being smaller than the third width; at least three lift pins disposed below the ring support surface and corresponding to each of the at least three grooves, each of the at least three lift pins having an upper support portion and a lower support portion, the upper support portion configured to support the second annular member from below by contacting a bottom surface of the groove of the second annular member through the through hole of the first annular member, and the lower support portion configured to support the first annular member from below by contacting an inclined surface of the first annular member that defines the lower hole portion; and at least one actuator configured to vertically move the at least three lift pins.

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