Substrate support, plasma processing apparatus, and substrate processing apparatus

Abstract

To provide a technique capable of performing lifting of only one ring of two rings constructing an edge ring, and lifting of the two rings at the same time with a less number of pins.SOLUTION: A substrate supporter comprises: a main body part; a first ring; a second ring; and a lift pin. The first ring includes a penetration hole, and is arranged on an annular region of the main body part. The second ring is arranged on the first ring. The second ring includes an inner peripheral surface that is opposite to an end surface of a substrate on a substrate support region of the main body part. In the lift pin, a lower rod includes an upper end surface which can come into contact with the first ring. An upper side rod is extended upward from the upper end surface of the lower side rod, and can come into contact with the second ring via a penetration hole of the first ring. The first ring contains the inner peripheral region, an intermediate mounting region where the penetration hole is formed, and an outer peripheral region. The first ring regulates a concave part on the intermediate mounting region, and the second ring is fitted to the concave part so as to be received on the intermediate mounting region.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] SUMMARY Exemplary embodiments of the present disclosure relate to a substrate support and a plasma processing apparatus. [Background technology]

[0002] Plasma processing of a substrate is performed using a plasma processing apparatus. When plasma processing is performed in the plasma processing apparatus, an edge ring is placed on a substrate support, and the substrate is placed on the substrate support within a region surrounded by the edge ring. The edge ring is sometimes called a focus ring.

[0003] The following Patent Document 1 discloses a focus ring composed of multiple rings. The multiple rings include a center ring and an outer ring. The center ring can be raised and lowered to adjust the characteristics of plasma processing at the edge of the substrate. The edge ring is raised and lowered using pusher pins. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-160666 Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure provides a technique for lifting and lowering only one of the two rings that make up an edge ring, and for lifting and lowering both rings simultaneously, using a small number of pins. [Means for solving the problem]

[0006] In one exemplary embodiment, a substrate support is provided. The substrate support includes a main body, a first ring, a second ring, and lift pins. The main body has a substrate support region and an annular region. The annular region surrounds the substrate support region. The first ring has a through hole and is disposed on the annular region. The second ring is disposed on the first ring. The second ring has an inner circumferential surface that faces an edge surface of a substrate on the substrate support region. The lift pins include a lower rod and an upper rod. The lower rod has an upper end surface that can abut against the first ring. The upper rod extends upward from the upper end surface of the lower rod and can abut against the second ring through the through hole of the first ring, and has a length greater than the length of the through hole. The first ring includes an inner peripheral region, an intermediate mounting region having a through hole formed therein, and an outer peripheral region, the upper surface of the intermediate mounting region being positioned lower than the upper surfaces of the inner peripheral region and the outer peripheral region, the first ring defining a recess on the intermediate mounting region, and the second ring being received on the intermediate mounting region and fitted into the recess. [Effects of the Invention]

[0007] According to one exemplary embodiment, it is possible to lift and lower only one of the two rings constituting the edge ring, and to lift and lower both rings simultaneously, using a small number of pins. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a schematic diagram of a plasma processing apparatus according to an exemplary embodiment; [Figure 2] 1A and 1B are diagrams illustrating a substrate support according to an exemplary embodiment; [Figure 3] 2 is a partial enlarged view of a substrate support according to an example embodiment; [Figure 4] FIG. 2 is a partial enlarged cross-sectional view of an edge ring according to an exemplary embodiment. [Figure 5] 2 is a partial enlarged view of a substrate support according to an example embodiment; [Figure 6] 2 is a partial enlarged view of a substrate support according to an example embodiment; [Figure 7] 2 is a partial enlarged view of a substrate support according to an example embodiment; [Figure 8] 2 is a partial enlarged view of a substrate support according to an example embodiment; [Figure 9] 1 is a flow diagram of a method according to an example embodiment including cleaning an edge ring. DETAILED DESCRIPTION OF THE INVENTION

[0009] Various exemplary embodiments are described below.

[0010] In one exemplary embodiment, a substrate support is provided. The substrate support includes a first region, a second region, and a lift mechanism. The second region extends radially outward from the first region and surrounds the first region. The second region is configured to support an edge ring. The edge ring includes a first ring and a second ring. The first ring has a mounting region. The second ring has an inner circumferential surface facing an edge surface of a substrate placed on the first region and is mounted on the mounting region. The lift mechanism includes lift pins. The lift mechanism is configured to raise and lower the first ring and the second ring supported by the lift pins. The lift pins have a first pillar and a second pillar. The first pillar has a first upper end surface that can abut against the first ring. The second pillar extends above the first pillar and is narrowed relative to the first pillar to expose the first upper end surface. The second columnar portion is movable through a through hole formed in the mounting area, has a second upper end surface that can abut against the second ring, and has a length that is longer than the thickness of the mounting area in the vertical direction.

[0011] In the substrate support of the above embodiment, when the first upper end surfaces of the lift pins are not in contact with the first ring, only the second ring, with the second upper end surfaces in contact, can be raised and lowered by the lift mechanism. Furthermore, when the first upper end surfaces are in contact with the first ring and the second upper end surfaces are in contact with the second ring, the first ring and the second ring can be raised and lowered simultaneously above the substrate support by the lift mechanism. Therefore, with the substrate support of the above embodiment, it is possible to raise and lower only one of the two rings constituting the edge ring, and to raise and lower both rings simultaneously, using a small number of lift pins.

[0012] In one exemplary embodiment, the first and second pillars each have a cylindrical shape, and in this embodiment, the diameter of the first pillar is greater than the diameter of the second pillar.

[0013] In one exemplary embodiment, the second pillar may have a first portion and a second portion. In this embodiment, the first portion extends upward from the first pillar. The second portion extends above the first portion to provide a second upper end surface. The width of the first portion is greater than the width of the second portion. In this embodiment, the first ring is supported by lift pins with the first portion of the second pillar partially disposed in the through-hole of the mounting area. The first portion is a portion of the second pillar that has a relatively large width. Therefore, movement of the first ring relative to the lift pins in a horizontal plane is suppressed. This increases the accuracy of positioning the first ring on the substrate support.

[0014] In one exemplary embodiment, the first columnar section, the first portion, and the second portion may have a cylindrical shape, wherein the diameter of the first columnar section is larger than the diameter of the first portion, and the diameter of the first portion is larger than the diameter of the second portion.

[0015] In one exemplary embodiment, the second post may further include a third portion extending between the first portion and the second portion, and the third portion may have a tapered surface.

[0016] In one exemplary embodiment, the tip of the second columnar portion, including the second upper end surface, may be tapered to fit into a tapered recess in the second ring. In this embodiment, the second ring is supported by the lift pins with the tip of the second columnar portion of the lift pin fitting into the recess in the second ring. This suppresses movement of the second ring relative to the lift pins in the horizontal plane. This increases the accuracy of positioning the second ring relative to the lift pins, and as a result, increases the accuracy of positioning the second ring on the first ring and the substrate support.

[0017] In another exemplary embodiment, a plasma processing apparatus is provided, comprising a chamber and a substrate support, the substrate support being any of the substrate support of the various exemplary embodiments described above, configured to support a substrate within the chamber.

[0018] In one exemplary embodiment, the plasma processing apparatus may further include a gas supply, an energy source, and a controller. The gas supply is configured to supply gas into the chamber. The energy source is configured to supply energy for generating plasma from the gas in the chamber. The controller is configured to control the lift mechanism, the gas supply, and the energy source. The lift mechanism further includes a drive device configured to raise and lower the lift pins. The controller may control the drive device to lift the edge ring or the second ring supported by the lift pins upward from the substrate support. With the edge ring or the second ring positioned above the substrate support, the controller may control the gas supply to supply a cleaning gas into the chamber and control the energy source to generate plasma from the cleaning gas.

[0019] In one exemplary embodiment, the plasma processing apparatus may further include another gas supply unit configured to supply an inert gas to the through-hole formed in the second region so that the lift pin is movable therethrough. According to this embodiment, discharge in the through-hole in the second region can be suppressed.

[0020] Various exemplary embodiments will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0021] FIG. 1 is a diagram schematically illustrating a plasma processing apparatus according to an exemplary embodiment. In FIG. 1, the plasma processing apparatus is shown in a partially cutaway state. The plasma processing apparatus 1 illustrated in FIG. 1 is a capacitively coupled plasma processing apparatus. The plasma processing apparatus 1 includes a chamber 10. The chamber 10 provides an internal space 10s therein. The central axis of the internal space 10s is an axis AX extending in the vertical direction.

[0022] In one embodiment, the chamber 10 includes a chamber body 12. The chamber body 12 has a generally cylindrical shape. An internal space 10s is provided within the chamber body 12. The chamber body 12 is made of, for example, aluminum. The chamber body 12 is electrically grounded. A plasma-resistant film is formed on the inner wall surface of the chamber body 12, i.e., the wall surface defining the internal space 10s. This film may be a film formed by anodizing or a ceramic film such as a film formed from yttrium oxide.

[0023] A passage 12p is formed in the sidewall of the chamber body 12. The substrate W passes through the passage 12p when being transferred between the internal space 10s and the outside of the chamber 10. A gate valve 12g is provided along the sidewall of the chamber body 12 to open and close the passage 12p.

[0024] The plasma processing apparatus 1 further includes a substrate support 16. Hereinafter, reference will be made to FIGS. 2 and 3 in addition to FIG. 1 . FIG. 2 is a diagram schematically illustrating a substrate support according to an exemplary embodiment. FIG. 3 is a partially enlarged view of the substrate support according to an exemplary embodiment. In FIG. 3, the substrate support is shown in a partially broken state. The substrate support 16 is configured to support a substrate W placed thereon in the chamber 10. The substrate W has a substantially disk-like shape. The substrate support 16 is supported by a support portion 17. The support portion 17 extends upward from the bottom of the chamber 10. The support portion 17 has a substantially cylindrical shape. The support portion 17 is made of an insulating material such as quartz.

[0025] The substrate support 16 has a first region 161 and a second region 162. The first region 161 is configured to support a substrate W placed thereon. The first region 161 is a substantially circular region in a plan view. The central axis of the first region 161 is the axis AX. In one embodiment, the first region 161 includes a base 18 and an electrostatic chuck 20. In one embodiment, the first region 161 may be composed of a portion of the base 18 and a portion of the electrostatic chuck 20. The base 18 and the electrostatic chuck 20 are provided in the chamber 10. The base 18 is made of a conductive material such as aluminum and has a substantially disk shape. The base 18 constitutes a lower electrode.

[0026] In one embodiment, the substrate support 16 includes a main body 2 and an edge ring 22. The main body 2 includes a base 18 and an electrostatic chuck 20. The main body 2 also includes a substrate support region 2a for supporting the substrate W, an annular region 2b for supporting the edge ring 22, and a sidewall 2c extending vertically between the substrate support region 2a and the annular region 2b. The annular region 2b surrounds the substrate support region 2a. The annular region 2b is located lower than the substrate support region 2a. Therefore, the upper end of the sidewall 2c is connected to the substrate support region 2a, and the lower end of the sidewall 2c is connected to the annular region 2b.

[0027] A flow path 18f is formed within the base 18. The flow path 18f is a flow path for a heat exchange medium. As the heat exchange medium, a liquid refrigerant or a refrigerant (e.g., chlorofluorocarbon) that cools the base 18 by vaporizing is used. A heat exchange medium supply device (e.g., a chiller unit) is connected to the flow path 18f. This supply device is provided outside the chamber 10. The heat exchange medium is supplied from the supply device to the flow path 18f. The heat exchange medium supplied to the flow path 18f is returned to the supply device.

[0028] The electrostatic chuck 20 is provided on the base 18. When the substrate W is processed in the chamber 10, it is placed on the first region 161 and the electrostatic chuck 20.

[0029] The second region 162 extends radially outward relative to the first region 161 and surrounds the first region 161. The second region 162 is a region that is substantially annular in plan view. An edge ring 22 is mounted on the second region 162. In one embodiment, the second region 162 may include the base 18. The second region 162 may further include the electrostatic chuck 20. In one embodiment, the second region 162 may be composed of another part of the base 18 and another part of the electrostatic chuck 20. The substrate W is placed within the region surrounded by the edge ring 22 and on the electrostatic chuck 20. Details of the edge ring 22 will be described later.

[0030] A through hole 162h is formed in the second region 162. In one embodiment, the main body 2 has the through hole 162h formed between the annular region 2b and the lower surface 2d of the main body 2. The through hole 162h is formed in the second region 162 so as to extend along the vertical direction. In one embodiment, a plurality of through holes 612h are formed in the second region 162. The number of through holes 612h may be the same as the number of lift pins 72 of the lift mechanism 70 described below. Each through hole 612h is arranged so as to be aligned in a straight line with a corresponding lift pin 72.

[0031] The electrostatic chuck 20 has a main body 20m and an electrode 20e. The main body 20m is made of a dielectric material such as aluminum oxide or aluminum nitride. The main body 20m has a substantially disk shape. The central axis of the electrostatic chuck 20 is an axis line AX. The electrode 20e is provided within the main body 20m. The electrode 20e has a film shape. A DC power supply is electrically connected to the electrode 20e via a switch. When a voltage from the DC power supply is applied to the electrode 20e, an electrostatic attractive force is generated between the electrostatic chuck 20 and the substrate W. The generated electrostatic attractive force attracts the substrate W to the electrostatic chuck 20, whereby the substrate W is held by the electrostatic chuck 20.

[0032] The plasma processing apparatus 1 may further include a gas supply line 25. The gas supply line 25 supplies a heat transfer gas, for example, He gas, from a gas supply mechanism to between the upper surface of the electrostatic chuck 20 and the rear surface (lower surface) of the substrate W.

[0033] The plasma processing apparatus 1 may further include an outer peripheral member 27. The outer peripheral member 27 extends in a circumferential direction radially outward from the substrate support 16 so as to surround the substrate support 16. The outer peripheral member 27 may also extend in a circumferential direction radially outward from the support portion 17 so as to surround the support portion 17. The outer peripheral member 27 may be composed of one or more parts. The outer peripheral member 27 may be formed from an insulator such as quartz.

[0034] The plasma processing apparatus 1 further includes an upper electrode 30. The upper electrode 30 is provided above the substrate support 16. The upper electrode 30 closes the upper opening of the chamber body 12 together with a member 32. The member 32 has insulating properties. The upper electrode 30 is supported on the upper part of the chamber body 12 via this member 32.

[0035] The upper electrode 30 includes a top plate 34 and a support 36. The lower surface of the top plate 34 defines an internal space 10s. A plurality of gas discharge holes 34a are formed in the top plate 34. Each of the plurality of gas discharge holes 34a penetrates the top plate 34 in the thickness direction (vertical direction). The top plate 34 is made of, for example, silicon, but is not limited thereto. Alternatively, the top plate 34 may have a structure in which a plasma-resistant film is provided on the surface of an aluminum member. This film may be a ceramic film, such as a film formed by anodizing or a film formed from yttrium oxide.

[0036] The support 36 detachably supports the top plate 34. The support 36 is made of a conductive material such as aluminum. A gas diffusion chamber 36a is provided inside the support 36. A plurality of gas holes 36b extend downward from the gas diffusion chamber 36a. The plurality of gas holes 36b are respectively connected to the plurality of gas discharge holes 34a. A gas introduction port 36c is formed in the support 36. The gas introduction port 36c is connected to the gas diffusion chamber 36a. A gas supply pipe 38 is connected to the gas introduction port 36c.

[0037] A gas source group 40 is connected to the gas supply pipe 38 via a valve group 41, a flow rate controller group 42, and a valve group 43. The gas source group 40, the valve group 41, the flow rate controller group 42, and the valve group 43 constitute a gas supply unit GS. The gas source group 40 includes a plurality of gas sources. Each of the valve group 41 and the valve group 43 includes a plurality of valves (e.g., on-off valves). The flow rate controller group 42 includes a plurality of flow rate controllers. Each of the plurality of flow rate controllers in the flow rate controller group 42 is a mass flow controller or a pressure-controlled flow rate controller. Each of the plurality of gas sources in the gas source group 40 is connected to the gas supply pipe 38 via a corresponding valve in the valve group 41, a corresponding flow rate controller in the flow rate controller group 42, and a corresponding valve in the valve group 43. The plasma processing apparatus 1 can supply gas from one or more selected gas sources of the gas source group 40 to the internal space 10s at individually adjusted flow rates.

[0038] A baffle plate 48 is provided between the substrate support 16 or the outer peripheral member 27 and the side wall of the chamber 10. The baffle plate 48 can be formed, for example, by coating an aluminum member with a ceramic such as yttrium oxide. A large number of through-holes are formed in the baffle plate 48. Below the baffle plate 48, an exhaust pipe 52 is connected to the bottom of the chamber 10. An exhaust device 50 is connected to the exhaust pipe 52. The exhaust device 50 has a pressure controller such as an automatic pressure control valve and a vacuum pump such as a turbomolecular pump, and is able to reduce the pressure in the internal space 10s.

[0039] The plasma processing apparatus 1 further includes a high-frequency power supply 61. The high-frequency power supply 61 is a power supply that generates high-frequency power (hereinafter referred to as "first high-frequency power"). The first high-frequency power is used to generate plasma from the gas in the chamber 10. The first high-frequency power has a first frequency. The first frequency is a frequency within a range of 27 to 100 MHz. The high-frequency power supply 61 is connected to the upper electrode 30 via a matching circuit 61m. The matching circuit 61m is configured to match the output impedance of the high-frequency power supply 61 with the impedance on the load side (upper electrode 30 side). Note that the high-frequency power supply 61 may be connected to the base 18 (i.e., the lower electrode) via the matching circuit 61m, instead of to the upper electrode 30.

[0040] The plasma processing apparatus 1 further includes a high-frequency power supply 62. The high-frequency power supply 62 is a power supply that generates high-frequency power (hereinafter referred to as "second high-frequency power") for attracting ions from the plasma to the substrate W. The second high-frequency power has a second frequency. The second frequency is lower than the first frequency. The second frequency is, for example, within a range of 400 kHz to 13.56 MHz. The high-frequency power supply 62 is connected to the base 18 (i.e., the lower electrode) via a matching circuit 62m. The matching circuit 62m is configured to match the output impedance of the high-frequency power supply 62 with the impedance on the load side (the base 18 side).

[0041] The plasma processing apparatus 1 may further include a control unit MC. The control unit MC is a computer equipped with a processor, a storage device, an input device, a display device, etc., and controls each part of the plasma processing apparatus 1. The control unit MC executes a control program stored in the storage device and controls each part of the plasma processing apparatus 1 based on recipe data stored in the storage device. Under the control of the control unit MC, the process specified by the recipe data is executed in the plasma processing apparatus 1.

[0042] The edge ring 22 and the substrate support 16 will now be described in more detail with reference to FIG. 4 in addition to FIGS. 1 to 3. FIG. 4 is a partially enlarged cross-sectional view of the edge ring according to one example embodiment. The edge ring 22 includes a first ring 221 and a second ring 222. FIG. 4 shows the first ring 221 and the second ring 222 separated from each other.

[0043] Each of the first ring 221 and the second ring 222 is a ring-shaped member. Each of the first ring 221 and the second ring 222 is made of a material appropriately selected depending on the plasma processing performed in the plasma processing apparatus 1. Each of the first ring 221 and the second ring 222 is made of, for example, silicon or silicon carbide.

[0044] The first ring 221 is mounted on the second region 162 so that its central axis is aligned with the axis AX. In one embodiment, the first ring 221 is disposed on the annular region 2b of the main body 2. In one embodiment, the first ring 221 may be mounted on the second region 162 and the electrostatic chuck 20. Note that the first ring 221 may also be mounted on a component in the second region 162 other than the electrostatic chuck 20. In one embodiment, as shown in FIG. 4 , the first ring 221 includes an inner circumferential region (inner portion) 221i, a mounting region (middle portion) 221m, and an outer circumferential region (outer portion) 221o. Each of the inner circumferential region 221i, the mounting region 221m, and the outer circumferential region 221o is annular and extends around the central axis of the first ring 221.

[0045] 1 to 3, the inner circumferential region 221i is provided closer to the central axis of the first ring 221 than the mounting region 221m and the outer circumferential region 221o, and extends in the circumferential direction. The outer circumferential region 221o extends radially outward from the inner circumferential region 221i and the mounting region 221m. When the substrate W is placed on the electrostatic chuck 20, the edge of the substrate W extends above or above the inner circumferential region 221i. The outer circumferential region 221o is spaced radially outward from the edge of the substrate W.

[0046] The mounting region 221m extends in the circumferential direction between the inner peripheral region 221i and the outer peripheral region 221o. A through hole 221h is formed in the mounting region 221m. The through hole 221h is formed in the mounting region 221m so as to extend along the vertical direction. In one embodiment, a plurality of through holes 221h are formed in the mounting region 221m. The number of through holes 221h may be the same as the number of lift pins 72 of the lift mechanism 70.

[0047] Each through-hole 221h has a size that does not allow a first columnar portion 721 (described later) of the corresponding lift pin 72 to be inserted therein, but allows a second columnar portion 722 (described later) of the corresponding lift pin 72 to be inserted therein. When each of the first columnar portion 721 and the second columnar portion 722 has a cylindrical shape, each through-hole 221h has a diameter that is smaller than the diameter of the first columnar portion 721 and slightly larger than the diameter of the second columnar portion 722 (or a first portion 722a (described later)). The first ring 221 is disposed on the second region 162 so that each through-hole 221h is aligned with the corresponding lift pin 72 on a straight line.

[0048] The upper surface of the mounting region 221m extends at a position lower in the height direction than the upper surfaces of the inner peripheral region 221i and the outer peripheral region 221o. Therefore, the first ring 221 defines a recess on the mounting region 221m. The second ring 222 is mounted on the mounting region 221m so as to fit into the recess on the mounting region 221m. When the substrate W is placed on the electrostatic chuck 20, the inner peripheral surface of the second ring 222 faces the edge face of the substrate W.

[0049] In one embodiment, the middle portion 221m is provided on the outer periphery of the inner portion 221i, and the outer portion 221o is provided on the outer periphery of the middle portion 221m. That is, the middle portion 221m is provided between the inner portion 221i and the outer portion 221o. The inner portion 221i has an upper surface, a lower surface, an inner peripheral surface, and an outer peripheral surface, the middle portion 221m has an upper surface and a lower surface, and the outer portion 221o has an upper surface, a lower surface, an inner peripheral surface, and an outer peripheral surface. The lower surfaces of the inner portion 221i, the middle portion 221m, and the outer portion 221o form a single horizontal plane on the lower surface of the first ring 221. Furthermore, the upper surface of the inner portion 221i is higher than the upper surface of the middle portion 221m, and the upper surface of the outer portion 221o is higher than the upper surfaces of the inner portion 221i and the middle portion 221m. That is, the inner portion 221i has a thickness in the vertical direction that is smaller than the thickness of the outer portion 221o. Furthermore, the middle portion 221m has a thickness in the vertical direction that is smaller than the thickness of the inner portion 221i and the thickness of the outer portion 221o. The substrate support region 2a of the main body 2 has an area smaller than the area of ​​the substrate W, and the upper surface of the inner portion 221i faces a part of the back surface of the substrate W on the substrate support region 2a. The inner peripheral surface of the inner portion 221i faces the side wall 2c of the main body 2. The outer peripheral surface of the inner portion 221i is connected to the inner peripheral edge of the upper surface of the middle portion 221m. The inner peripheral surface of the outer portion 221o is connected to the outer peripheral edge of the upper surface of the middle portion 221m. That is, the first ring 221 has a recess defined by the outer peripheral surface of the inner portion 221i, the upper surface of the middle portion 221m, and the inner peripheral surface of the outer portion 221o.

[0050] The lower surface of the second ring 222 is generally flat. In one embodiment, as shown in FIG. 4 , the lower surface of the second ring 222 further includes a tapered surface, which defines a recess 222r. In one embodiment, the lower surface of the second ring 222 defines a plurality of recesses 222r. The number of tapered surfaces and the number of recesses 222r of the second ring 222 can be equal to the number of lift pins 72 of the lift mechanism 70. Each recess 222r has a size that allows the tip of the second post 722 of the corresponding lift pin 72 to fit therein. The second ring 222 is positioned on the mounting region 221m so that each recess 222r is aligned with the corresponding lift pin 72 and the corresponding through-hole 221h.

[0051] In one embodiment, the second ring 222 is accommodated in a recess of the first ring 221. That is, the second ring 222 is disposed on the upper surface of the middle portion 221m of the first ring 221. In one embodiment, the first ring 221 and the second ring 222 are configured such that, when they are disposed on the annular region 2b, the upper surfaces of the outer portion 221o of the first ring 221 and the second ring 222 are at substantially the same height as the upper surface of the substrate W on the substrate support region 2a. In addition, the second ring 222 has an inner peripheral surface 222a that faces the edge surface of the substrate W on the substrate support region 2a when the first ring 221 and the second ring 222 are disposed on the annular region 2b.

[0052] As shown in FIGS. 1 to 3, the substrate support 16 further includes a lift mechanism 70. The lift mechanism 70 includes lift pins 72 and is configured to raise and lower the first ring 221 and the second ring 222. In one embodiment, the lift mechanism 70 includes a plurality of lift pins 72. The number of lift pins 72 in the lift mechanism 70 can be any number as long as the number is sufficient to support the edge ring 22 and raise and lower the edge ring 22. The number of lift pins 72 in the lift mechanism 70 is, for example, three.

[0053] Each lift pin 72 may be formed from an insulating material. Each lift pin 72 may be formed from, for example, sapphire, alumina, quartz, silicon nitride, aluminum nitride, or resin. Each lift pin 72 includes a first columnar portion (lower rod) 721 and a second columnar portion (upper rod) 722. The first columnar portion 721 extends in the vertical direction. The first columnar portion 721 has a first upper end surface 721t. The first upper end surface 721t is capable of abutting against the lower surface of the first ring 221.

[0054] The second columnar portion 722 extends in the vertical direction above the first columnar portion 721. The second columnar portion 722 is narrowed relative to the first columnar portion 721 so as to expose a first upper end surface 721t. In one embodiment, the first columnar portion 721 and the second columnar portion 722 each have a cylindrical shape. In this embodiment, the diameter of the first columnar portion 721 is larger than the diameter of the second columnar portion 722. The second columnar portion 722 is movable up and down through the through-hole 221h of the mounting region 221m. The vertical length of the second columnar portion 722 is longer than the vertical thickness of the mounting region 221m.

[0055] The second columnar portion 722 has a second upper end surface 722t. The second upper end surface 722t is capable of abutting against the second ring 222. In one embodiment, the tip of the second columnar portion 722, including the second upper end surface 722t, may be tapered so as to fit into the corresponding recess 222r.

[0056] In one embodiment, the second columnar portion 722 may include a first portion 722a and a second portion 722b. The first portion 722a is columnar and extends upward from the first columnar portion 721. The second portion 722b is columnar and extends above the first portion 722a. The second portion 722b provides a second top surface 722t. In this embodiment, the width of the first portion 722a is greater than the width of the second portion 722b.

[0057] In one embodiment, the first columnar portion 721, the first portion 722a, and the second portion 722b may each have a cylindrical shape, and the diameter of the first columnar portion 721 is larger than the diameter of the first portion 722a, which is larger than the diameter of the second portion 722b.

[0058] In one embodiment, the second columnar portion 722 may further include a third portion 722c extending between the first portion 721a and the second portion 722b. In this embodiment, the third portion 722c has a tapered surface.

[0059] In one embodiment, the lift mechanism 70 includes one or more actuators 74. The one or more actuators 74 are configured to raise and lower the plurality of lift pins 72. Each of the one or more actuators 74 may include, for example, a motor.

[0060] 2, the plasma processing apparatus 1 may further include another gas supply unit 76. The gas supply unit 76 supplies gas to each of the through-holes 162h to prevent discharge in each of the through-holes 162h. The gas supplied from the gas supply unit 76 to each of the through-holes 162h is an inert gas. The gas supplied from the gas supply unit 76 to each of the through-holes 162h is, for example, helium gas.

[0061] In one embodiment, the lower rod 721 has an upper end surface 721t that can abut against the first ring 221, and the upper rod 722 extends upward from the upper end surface 721t of the lower rod 721 and can abut against the second ring 222 through the through hole 221h of the first ring 221, and has a length greater than the length of the through hole 221h.

[0062] In one embodiment, the upper rod 722 is thinner than the lower rod 721 .

[0063] In one embodiment, the lower rod 721 and the upper rod 722 each have a cylindrical shape, and the diameter of the lower rod 721 is larger than the diameter of the upper rod 722 .

[0064] In one embodiment, the upper rod 722 has a first portion 722a extending upward from the lower rod 721 and a second portion 722b extending upward from the first portion 722a and including a tip portion 722t, the first portion 722a being thicker than the second portion 722b.

[0065] In one embodiment, the lower rod 721, the first portion 722a, and the second portion 722b have a cylindrical shape, and the first portion 722a has a diameter smaller than that of the lower rod 721 and larger than that of the second portion 722b.

[0066] In one embodiment, the upper rod 722 includes a tapered portion 722c between the first portion 722a and the second portion 722b.

[0067] In one embodiment, the second ring 222 has a recess 222r into which the tip 722t of the upper rod 722 fits.

[0068] Reference will now be made to FIGS. 5 to 8. Each of FIGS. 5 to 8 is a partially enlarged view of a substrate support according to an example embodiment. In each of FIGS. 5 to 8, the substrate support is shown in a partially cutaway state. FIG. 5 shows a state in which only the second ring 222 is disposed above the substrate support 16. FIG. 6 shows a state in which the first upper end surfaces 721t of the lift pins 72 abut against the first ring 221. FIG. 7 shows a state in which both the first ring 221 and the second ring 222 are disposed above the substrate support 16. FIG. 8 shows a state in which the first ring 221 and the second ring 222 are transferred from the lift pins 72 of the lift mechanism 70 to the transfer robot.

[0069] 5, with the substrate support 16, only the second ring 222, with which the second upper end surfaces 722t of the lift pins 72 are in contact, can be raised and lowered by the lift mechanism 70 while the first upper end surfaces 721t of the lift pins 72 are not in contact with the first ring 221. By adjusting the height position of only the second ring 222 with the lift mechanism 70, the height position of the boundary between the plasma and the sheath can be adjusted. As a result, the characteristics of the plasma processing for the edge of the substrate W can be adjusted.

[0070] Furthermore, the lift mechanism 70 can move only the second ring 222 upward from the substrate support 16, and the second ring 222 can be handed over from the plurality of lift pins 72 to a handler of the transfer robot, and the transfer robot can then carry the second ring 222 out of the chamber 10. Thereafter, a new second ring 222 can be carried into the chamber 10 by the transfer robot, and the new second ring 222 can be placed on the mounting region 221m using the lift mechanism 70.

[0071] In one embodiment, the second ring 222 is disposed in a recess on the mounting area 221m. This embodiment allows for high accuracy in positioning of the second ring 222 relative to the first ring 221 and the substrate support 16.

[0072] In one embodiment, the second ring 222 is supported by each lift pin 72 with the tip of the second columnar portion 722 of each lift pin 72 fitted into the corresponding recess 222r of the second ring 222. This suppresses movement of the second ring 222 relative to each lift pin 72 in the horizontal plane. This increases the accuracy of positioning the second ring 222 relative to each lift pin 72, and as a result, increases the accuracy of positioning the second ring 222 on the first ring 221 and the substrate support 16.

[0073] When the plurality of lift pins 72 supporting the second ring 222 are further moved upward, the first upper end surface 721t of each lift pin 72 comes into contact with the first ring 221, as shown in FIG. 6 . That is, when the plurality of lift pins 72 are further moved upward, a state is created in which the first upper end surface 721t comes into contact with the first ring 221 and the second upper end surface 722t comes into contact with the second ring 222. In this state, as shown in FIG. 7 , the first ring 221 and the second ring 222 can be simultaneously raised and lowered by the lift mechanism 70 above the substrate support 16. Therefore, with the substrate support 16, it is possible to raise and lower only one of the two rings constituting the edge ring 22, or to simultaneously raise and lower both rings, using a small number of lift pins 72.

[0074] 8 , when the handler of the transport robot TR is moved below the edge ring 22 and the plurality of lift pins 72 is moved downward, the edge ring 22 can be transferred from the plurality of lift pins 72 to the handler of the transport robot TR. Thereafter, the edge ring 22 can be carried out of the chamber 10 by the transport robot TR. Thereafter, the edge ring 22 in which one or both of the first ring 221 and the second ring 222 have been replaced with new parts can be carried into the chamber 10 by the transport robot TR, and the edge ring 22 can be placed on the second region 162 by the lift mechanism 70.

[0075] In one embodiment, as described above, the second columnar portion 722 of each lift pin 72 has a first portion 722a and a second portion 722b. The first portion 722a extends upward from the first columnar portion 721 and has a width greater than that of the second portion 722b. In this embodiment, as shown in FIG. 7 , the first ring 221 is supported by each lift pin 72 with the first portion 722a partially disposed in the through-hole 221h. The first portion 722a is a portion of the second columnar portion 722 that has a relatively large width. Therefore, movement of the first ring 221 relative to each lift pin 72 in the horizontal plane is suppressed. This increases the accuracy of positioning the first ring 221 on the substrate support 16.

[0076] A method MT including cleaning the edge ring will be described below with reference to FIG. 9. FIG. 9 is a flowchart of a method including cleaning the edge ring according to an example embodiment. Control of each part of the plasma processing apparatus 1 by a controller MC for performing the method MT will also be described below.

[0077] 9 may be performed when replacing one or both of the first ring 221 and the second ring 222 with new parts. Each of the first ring 221 and the second ring 222 is replaced when it is worn to the extent that replacement is necessary as a result of a plasma process performed in the plasma processing apparatus 1.

[0078] The controller MC may determine that replacement of the first ring 221 is necessary when the length of time that the first ring 221 is used in the plasma processing is equal to or longer than a first reference time length. The controller MC may determine that replacement of the second ring 222 is necessary when the length of time that the second ring 222 is used in the plasma processing is equal to or longer than a second reference time length. The second reference time length may be shorter than the first reference time length.

[0079] Alternatively, the control unit MC may determine that replacement of the first ring 221 is necessary when the thickness of the first ring 221 detected by the optical sensor is less than or equal to a first reference thickness. The control unit MC may determine that replacement of the second ring 222 is necessary when the thickness of the second ring 222 detected by the optical sensor is less than or equal to a second reference thickness. The optical sensor may be an optical interferometer.

[0080] Alternatively, the controller MC may determine that replacement of the first ring 221 is necessary when the torque of the motor of the drive device 74 required to lift the edge ring 22 upward from the substrate support 16 is less than or equal to a first reference torque. Alternatively, the controller MC may determine that replacement of both the first ring 221 and the second ring 222 is necessary when the torque of the motor of the drive device 74 required to lift the edge ring 22 upward from the substrate support 16 is less than or equal to a reference torque. The controller MC may determine that replacement of the second ring 222 is necessary when the torque of the motor of the drive device 74 required to lift the second ring 222 upward from the substrate support 16 is less than or equal to a second reference torque.

[0081] In step ST1 of the method MT, the second ring 222 or the edge ring 22, i.e., both the first ring 221 and the second ring 222, are supported by a plurality of lift pins 72 and lifted upward from the substrate support 16. In step ST1, the controller MC controls the drive device 74 of the lift mechanism 70 to lift the second ring 222 or the edge ring 22 upward from the substrate support 16. As a result of performing step ST1, a state is created in which the second ring 222 is positioned above the substrate support 16, as shown in FIG. 6. Alternatively, as a result of performing step ST1, a state is created in which both the first ring 221 and the second ring 222 are positioned above the substrate support 16, as shown in FIG. 7.

[0082] In the subsequent step ST2, plasma is generated from the cleaning gas in the chamber 10 in the state shown in FIG. 6 or 7 . Then, chemical species from the plasma clean the second ring 222 or the edge ring 22. By the cleaning in step ST2, substances adhering to the second ring 222 or the edge ring 22 can be removed. In step ST2, the control unit MC controls the gas supply unit GS to supply the cleaning gas into the chamber 10. In step ST2, the control unit MC controls the exhaust device 50 to set the pressure in the chamber 10 to a specified pressure. In step ST2, the control unit MC controls the energy source of the plasma processing apparatus 1, i.e., the high-frequency power supply 61 and / or the high-frequency power supply 62, to generate plasma from the clean gas in the chamber 10.

[0083] In the subsequent step ST3, the second ring 222 or the edge ring 22 is carried out of the chamber 10 by the transfer robot. The transfer robot can be controlled by the control unit MC. As described above, the cleaning in step ST2 removes substances adhering to the second ring 222 or the edge ring 22. Therefore, contamination of the transfer path of the second ring 222 or the edge ring 22 outside the chamber 10 is suppressed.

[0084] In the subsequent step ST4, a replacement part corresponding to one or both of the first ring 221 and the second ring 222 is carried into the chamber 10 by the transfer robot. The replacement part may be a new, i.e., unused, part. The replacement part is then transferred from the handler of the transfer robot to the plurality of lift pins 72 of the lift mechanism 70. Thereafter, the plurality of lift pins 72 are lowered, thereby loading the replacement part onto the substrate support 16. In step ST4, the transfer robot and the drive device 74 of the lift mechanism 70 may be controlled by the control unit MC.

[0085] In one embodiment, the controller MC is configured to control the actuators 74 so that the lift pins 72 lift the first and second rings 221, 222 or the second ring 222 from the substrate support 16. For example, the controller MC is configured to control the actuators 74 so that the lift pins 72 lift both the first and second rings 221, 222 from the substrate support 16. Furthermore, for example, the controller MC is configured to control the actuators 74 so that the lift pins 72 lift only the second ring 222 from the substrate support 16 while leaving the first ring 221 on the substrate support 16.

[0086] In one embodiment, the controller MC is configured to control the gas supplier GS and the energy source (high frequency power supply 61) to supply a cleaning gas into the chamber 10 and generate plasma from the cleaning gas. Such control is performed while the first and second rings 221, 222 or the second ring 222 is being lifted from the substrate support 16. For example, the above control is performed while both the first and second rings 221, 222 are being lifted from the substrate support 16. Also, for example, the above control is performed while the second ring 222 is being lifted from the substrate support 16 while the first ring 221 remains on the substrate support 16.

[0087] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various omissions, substitutions, and modifications may be made. Furthermore, elements in different embodiments may be combined to form other embodiments.

[0088] For example, a recess may be formed on one of the first ring 221 and the second ring 222, and a protrusion that fits into the recess may be formed on the other ring. In this case, the accuracy of positioning the first ring 221 and the second ring 222 is improved.

[0089] Furthermore, the plasma processing apparatus equipped with the substrate support 16 is not limited to the plasma processing apparatus 1. The plasma processing apparatus equipped with the substrate support 16 may be a capacitively coupled plasma processing apparatus different from the plasma processing apparatus 1. Alternatively, the plasma processing apparatus equipped with the substrate support 16 may be a different type of plasma processing apparatus. Examples of other types of plasma processing apparatus include an inductively coupled plasma processing apparatus and a plasma processing apparatus that generates plasma using surface waves such as microwaves.

[0090] From the foregoing, it will be understood that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the appended claims. [Explanation of symbols]

[0091] 16...substrate support, 161...first region, 162...second region, 18...base, 20...electrostatic chuck, 22...edge ring, 221...first ring, 221m...mounting region, 222...second ring, 70...lift mechanism, 72...lift pin, 721...first columnar portion, 721t...first upper end surface, 722...second columnar portion, 722t...second upper end surface.

Claims

1. a body portion having a substrate support region and an annular region, the annular region surrounding the substrate support region; a first ring disposed on the annular region and having a through hole; a second ring disposed on the first ring, the second ring having an inner circumferential surface facing an edge of a substrate on the substrate support region; a lift pin including a lower rod and an upper rod, wherein the lower rod has an upper end surface capable of contacting the first ring, the upper rod extends upward from the upper end surface of the lower rod and is capable of contacting the second ring via the through hole of the first ring, and the upper rod has a length in a direction in which the through hole passes through the first ring that is greater than a length of the through hole in said direction; a lift mechanism configured to raise and lower only the second ring against which the upper rod of the lift pin abuts, when the lower rod of the lift pin is not in contact with the first ring, and to simultaneously raise and lower the first ring against which the lower rod of the lift pin abuts and the second ring against which the upper rod of the lift pin abuts; Equipped with the first ring includes an inner circumferential region, an intermediate mounting region in which the through hole is formed, and an outer circumferential region, and an upper surface of the intermediate mounting region is positioned lower than upper surfaces of the inner circumferential region and the outer circumferential region; the first ring defines a recess above the intermediate mounting area, and the second ring is received above the intermediate mounting area and fits into the recess; Board support.

2. The substrate support of claim 1 , wherein the upper rod is thinner than the lower rod.

3. each of the lower rod and the upper rod has a cylindrical shape; The diameter of the lower rod is greater than the diameter of the upper rod.

3. The substrate support according to claim 1 or 2.

4. The upper rod is a first portion extending upward from the lower rod; a second portion extending upward from the first portion and including a tip; and The first portion is thicker than the second portion. The substrate support of claim 3 .

5. the lower rod, the first portion, and the second portion have a cylindrical shape; the first portion has a diameter smaller than the diameter of the lower rod and larger than the diameter of the second portion; The substrate support of claim 4 .

6. the upper rod further includes a tapered portion between the first and second portions. The substrate support of claim 5 .

7. The second ring has a recess into which the tip of the upper rod fits. The substrate support of claim 6 .

8. the inner peripheral region of the first ring has a first thickness extending from a lower surface of the inner peripheral region to the upper surface of the inner peripheral region, the intermediate mounting region of the first ring has a second thickness extending from a lower surface of the intermediate mounting region to the upper surface of the intermediate mounting region, and the outer peripheral region of the first ring has a third thickness extending from a lower surface of the outer peripheral region to the upper surface of the outer peripheral region; the lower surface of the inner peripheral region, the lower surface of the intermediate mounting region, and the lower surface of the outer peripheral region form a single plane on the lower surface of the first ring, and the first thickness and the third thickness are greater than the second thickness; The substrate support of claim 1 .

9. At least a portion of the inner peripheral region, the intermediate mounting region, and the outer peripheral region are supported on the annular region of the main body portion. The substrate support of claim 1 .

10. The main body includes a base and an electrostatic chuck disposed on the base. The substrate support according to any one of claims 1 to 9.

11. the first ring is positioned above the electrostatic chuck; The substrate support of claim 10.

12. a chamber; a substrate support according to any one of claims 1 to 11, which is arranged in the chamber; a drive unit configured to raise and lower the lift pins; A plasma processing apparatus comprising:

13. a gas supply configured to supply a cleaning gas into the chamber; an energy source configured to provide energy to generate a plasma from the cleaning gas within the chamber; A control unit; Further provided with The control unit controlling the drive device so that the lift pins lift the first ring and the second ring or the second ring from the substrate support; configured to control the gas supply and the energy source to supply the cleaning gas into the chamber and generate plasma from the cleaning gas while the first ring and the second ring or the second ring is lifted from the substrate support. The plasma processing apparatus according to claim 12 .

14. The control unit controlling the driving device so that the lift pins lift the first ring and the second ring, or the second ring, from the substrate support to remove the first ring and the second ring, or the second ring, from the plasma processing apparatus; controlling the drive device so that the lift pins lift only the second ring from the substrate support to adjust a height position of a boundary between the plasma and the sheath during plasma processing; The plasma processing apparatus according to claim 13 .

15. A substrate processing chamber; a substrate support disposed within the substrate processing chamber; A substrate processing apparatus comprising: The substrate support includes: a body portion having a substrate support region and an annular region surrounding the substrate support region; a first ring disposed on the annular region, the first ring having an inner portion, a middle portion having a plurality of through holes, and an outer portion; a second ring disposed on the intermediate portion of the first ring, the second ring having a radially outer end surface surrounded by the outer portion of the first ring; a plurality of lift pins respectively corresponding to the plurality of through holes, each of the plurality of lift pins having a lower portion and an upper portion, the lower portion configured to support the first ring, and the upper portion configured to support the second ring via a corresponding one of the plurality of through holes; a lift mechanism configured to raise and lower only the second ring against which the upper portions of each of the plurality of lift pins abut, while the lower portions of each of the plurality of lift pins are not in contact with the first ring, and to simultaneously raise and lower the first ring against which the lower portions of each of the plurality of lift pins abut and the second ring against which the upper portions of each of the plurality of lift pins abut; A substrate processing apparatus comprising:

16. the first ring has a recess defined by an outer wall of the inner portion, an upper surface of the middle portion, and an inner wall of the outer portion, and the second ring fits into the recess; The substrate processing apparatus according to claim 15 .

17. the second ring has a plurality of recesses on its lower surface corresponding to the plurality of lift pins, the upper portion of each of the plurality of lift pins is configured to support the second ring within a corresponding one of the plurality of recesses. The substrate processing apparatus according to claim 15 .

18. the intermediate portion of the first ring is located radially outward of the inner portion of the first ring; The substrate processing apparatus according to claim 15 .

19. a radially outer end surface of the inner portion of the first ring is surrounded by the second ring; The substrate processing apparatus according to claim 15 .

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