Substrate support and plasma processing apparatus

Abstract

A substrate support and a plasma processing apparatus are provided. The substrate support includes a main body portion, a first ring, a second ring, and a lift pin. The main body portion has a substrate supporting region and a ring-shaped region. The ring-shaped region surrounds the substrate supporting region. The first ring has a through-hole and is disposed on the ring-shaped region. The second ring is disposed on the first ring. The second ring has an inner peripheral surface that faces an end surface of a substrate on the substrate supporting region. The lift pin includes a lower side rod and an upper side rod. The lower side rod has an upper end surface that can abut against the first ring. The upper side rod extends upward from the upper end surface of the lower side rod, can abut against the second ring via the through-hole of the first ring, and has a length greater than a length of the through-hole. According to the present invention, lift of only one of two rings constituting an edge ring and simultaneous lift of the two rings can be performed with a smaller number of pins.

Description

Technical Field

[0001] Illustrative embodiments of the present invention relate to a substrate support and a plasma processing apparatus. Background Art

[0002] Plasma processing of substrates is performed using a plasma processing apparatus. During plasma processing in a plasma processing apparatus, an edge ring is placed on a substrate support, and the substrate is positioned within an area enclosed by the edge ring. This edge ring is sometimes referred to as a focus ring.

[0003] Patent Document 1 below discloses a focus ring composed of multiple rings. The multiple rings include a central ring and outer rings. The central ring can be raised and lowered to adjust the plasma processing characteristics at the edge of the substrate. The edge ring is raised and lowered using a push rod tip.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2018-160666. Summary of the Invention

[0007] Problems to be solved by the invention

[0008] The present invention provides a technology for lifting and lowering only one of two rings constituting an edge ring or lifting and lowering both rings simultaneously using a small number of pins.

[0009] Technical means to solve the problem

[0010] In an exemplary embodiment, a substrate support is provided. The substrate support includes a main body, a first ring, a second ring and a lifting pin. The main body has a substrate supporting area and an annular area. The annular area surrounds the substrate supporting area. The first ring has a through hole and is arranged on the annular area. The second ring is arranged on the first ring. The second ring has an inner circumferential surface facing the end face of the substrate on the substrate supporting area. The lifting pin includes a lower rod and an upper rod. The lower rod has an upper end face that can abut against the first ring. The upper rod extends upward from the upper end face of the lower rod, can abut against the second ring via the through hole of the first ring, and has a length greater than the length of the through hole.

[0011] Effects of the Invention

[0012] Therefore, according to one exemplary embodiment, it is possible to lift and lower only one of the two rings constituting the edge ring or to lift and lower both rings simultaneously using a relatively small number of pins. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1FIG. 1 is a diagram schematically showing a plasma processing apparatus according to an exemplary embodiment.

[0014] Figure 2 This is a diagram schematically showing a substrate support according to an exemplary embodiment.

[0015] Figure 3 FIG. 1 is an enlarged partial view of a substrate support according to an exemplary embodiment.

[0016] Figure 4 FIG. 4 is an enlarged partial cross-sectional view of an edge ring according to an exemplary embodiment.

[0017] Figure 5 FIG. 1 is an enlarged partial view of a substrate support according to an exemplary embodiment.

[0018] Figure 6 FIG. 1 is an enlarged partial view of a substrate support according to an exemplary embodiment.

[0019] Figure 7 FIG. 1 is an enlarged partial view of a substrate support according to an exemplary embodiment.

[0020] Figure 8 FIG. 1 is an enlarged partial view of a substrate support according to an exemplary embodiment.

[0021] Figure 9 is a flow chart of a method of an exemplary embodiment including cleaning of an edge ring.

[0022] Description of Reference Numerals

[0023] 16…substrate support, 161…first area, 162…second area, 18…base, 20…electrostatic suction cup, 22…edge ring, 221…first ring, 221m…loading area, 222…second ring, 70…lifting mechanism, 72…lifting pin, 721…first columnar portion, 721t…first upper end surface, 722…second columnar portion, 722t…second upper end surface. DETAILED DESCRIPTION

[0024] Various exemplary embodiments will be described below.

[0025] In an exemplary embodiment, a substrate support is provided. The substrate support includes a first region, a second region, and a lifting mechanism. The second region extends radially outward relative to 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 loading region. The second ring has an inner peripheral surface facing the end surface of the substrate loaded on the first region and is loaded on the loading region. The lifting mechanism includes lifting pins. The lifting mechanism is configured to lift and lower the first ring and the second ring supported by the lifting pins. The lifting pins have a first columnar portion and a second columnar portion. The first columnar portion has a first upper end surface that can abut against the first ring. The second columnar portion extends above the first columnar portion and is narrower than the first columnar portion so that the first upper end surface is exposed. The second columnar portion can move through a through hole formed in the loading region. The second columnar portion has a second upper end surface that can abut against the second ring. The length of the second columnar portion is greater than the vertical thickness of the mounting region.

[0026] In the substrate support device of the above embodiment, when the first upper end surfaces of the lift pins are not in contact with the first ring, the lift mechanism can be used to lift and lower only the second ring, with which the first upper end surface is in contact. 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 lift mechanism can be used to simultaneously lift and lower both the first and second rings above the substrate support. Therefore, the substrate support device of the above embodiment can lift and lower only one of the two rings constituting the edge ring, or both rings simultaneously, using a relatively small number of lift pins.

[0027] In one exemplary embodiment, the first columnar portion and the second columnar portion each have a cylindrical shape. In this embodiment, the diameter of the first columnar portion is larger than the diameter of the second columnar portion.

[0028] In an exemplary embodiment, the second columnar portion may include a first portion and a second portion. In this embodiment, the first portion extends upward from the first columnar portion. The second portion extends above the first portion and provides 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 the lift pins in a state where the first portion of the second columnar portion is partially disposed in the through-hole of the loading area. The first portion is the portion with the larger width in the second columnar portion. Therefore, the movement of the first ring within the horizontal plane relative to the lift pins can be suppressed. Therefore, the positioning accuracy of the first ring on the substrate support is improved.

[0029] In an exemplary embodiment, the first columnar portion, the first part, and the second part may have a cylindrical shape. In this embodiment, the diameter of the first columnar portion is larger than the diameter of the first part, and the diameter of the first part is larger than the diameter of the second part.

[0030] In an exemplary embodiment, the second columnar portion may further include a third portion extending between the first portion and the second portion, wherein the third portion has a tapered surface.

[0031] In one exemplary embodiment, the tip of the second columnar portion, including the second upper end surface, can be tapered to fit within the tapered recess of the second ring. In this embodiment, the second ring is supported by the lift pins while the tip of the second columnar portion of the lift pins fits within the recess of the second ring. This suppresses horizontal movement of the second ring relative to the lift pins. This improves the positioning accuracy of the second ring relative to the lift pins, and consequently, the positioning accuracy of the second ring on the first ring and substrate support.

[0032] In another exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber and a substrate supporter. The substrate supporter is any of the substrate supports in the various exemplary embodiments described above and is configured to support a substrate in the chamber.

[0033] In an exemplary embodiment, the plasma processing apparatus may further include a gas supply unit, an energy source, and a control unit. The gas supply unit 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 control unit is configured to control the lifting mechanism, the gas supply unit, and the energy source. The lifting mechanism also includes a drive device capable of lifting and lowering the lifting pins. The control unit may control the drive device so as to lift the edge ring or the second ring supported by the lifting pins upward from the substrate support. The control unit may control the gas supply unit so as to supply a clean gas into the chamber when the edge ring or the second ring is located above the substrate support, and may control the energy source to generate plasma from the clean gas.

[0034] In one exemplary embodiment, the plasma processing apparatus may further include another gas supply unit configured to supply an inert gas to the through-holes formed in the second region to enable the lift pins to move therein. This embodiment can suppress discharge in the through-holes in the second region.

[0035] Hereinafter, various exemplary embodiments will be described in detail with reference to the accompanying drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

[0036] Figure 1 FIG. 1 is a diagram schematically showing a plasma processing apparatus according to an exemplary embodiment. Figure 1 In FIG, the plasma processing apparatus is shown in a partially cut-away state. Figure 1The plasma processing apparatus 1 shown is a capacitively coupled plasma processing apparatus. The plasma processing apparatus 1 includes a chamber 10. The chamber 10 defines an internal space 10s. The central axis of the internal space 10s is an axis AX extending in the vertical direction.

[0037] 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 formed, for example, of aluminum. 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. The 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 ceramic film such as a film formed by anodization or a film formed of yttrium oxide.

[0038] A line 12p is formed on the sidewall of the chamber body 12. When the substrate W is transported between the interior space 10s and the outside of the chamber 10, the substrate W passes through the line 12p. A gate valve 12g is provided along the sidewall of the chamber body 12 to open and close the line 12p.

[0039] The plasma processing apparatus 1 further includes a substrate support 16. Figure 1 as well as Figure 2 and Figure 3 . Figure 2 This is a diagram schematically showing a substrate support according to an exemplary embodiment. Figure 3 FIG. 1 is an enlarged partial view of a substrate support according to an exemplary embodiment. Figure 3 In the figure, the substrate support is shown partially cut away. The substrate support 16 is configured to support a substrate W placed thereon within the chamber 10. The substrate W has a generally disc-shaped 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 generally cylindrical shape and is formed of an insulating material such as quartz.

[0040] 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 substantially circular when viewed from above. 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 disposed inside the chamber 10. The base 18 is formed of a conductive material such as aluminum and has a substantially disc shape. The base 18 constitutes a lower electrode.

[0041] 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. Furthermore, the main body 2 includes a substrate support region 2a for supporting a substrate W; an annular region 2b for supporting the edge ring 22; and a sidewall 2c extending longitudinally between the substrate support region 2a and the annular region 2b. The annular region 2b includes the substrate support region 2a. The annular region 2b is located at a lower position 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.

[0042] A flow path 18f is formed in 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 that cools the base 18 by gasification (for example, Freon) can be used. A heat exchange medium supply device (for example, a cooling unit) is connected to the flow path 18f. The supply device is provided outside the chamber 10. The heat exchange medium is supplied to the flow path 18f from the supply device. The heat exchange medium supplied to the flow path 18f returns to the supply device.

[0043] The electrostatic chuck 20 is provided on the susceptor 18 . When the substrate W is processed in the chamber 10 , it is placed on the first area 161 and on the electrostatic chuck 20 .

[0044] The second region 162 extends radially outward relative to the first region 161 and surrounds the first region 161. The second region 162 is generally annular in a plan view. An edge ring 22 is mounted on the second region 162. In one embodiment, the second region 162 may include a base 18. The second region 162 may also include an electrostatic chuck 20. In one embodiment, the second region 162 may be composed of another portion of the base 18 and another portion of the electrostatic chuck 20. The substrate W is mounted in the region surrounded by the edge ring 22 and on the electrostatic chuck 20. The edge ring 22 will be described in detail later.

[0045] A through-hole 162h is formed in the second region 162. In one embodiment, the main body 2 has a 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 in 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 can be the same as the number of lift pins 72 of the lift mechanism 70 described later. Each through-hole 612h is arranged so as to be aligned with the corresponding lift pin 72.

[0046] The electrostatic chuck 20 includes a main body 20m and an electrode 20e. The main body 20m is formed of a dielectric such as aluminum oxide or aluminum nitride. The main body 20m has a roughly disk-like shape. The central axis of the electrostatic chuck 20 is the axis AX. The electrode 20e is disposed within the main body 20m. The electrode 20e has a roughly membrane-like shape. The electrode 20e is electrically connected to a DC power supply via a switch. When a voltage from the DC power supply is applied to the electrode 20e, an electrostatic attraction is generated between the electrostatic chuck 20 and the substrate W. Due to the generated electrostatic attraction, the substrate W is attracted to the electrostatic chuck 20 and held by the electrostatic chuck 20.

[0047] The plasma processing apparatus 1 may further include a gas supply line 25. The gas supply line 25 supplies a heat transfer gas, such as He gas, from a gas supply mechanism between the upper surface of the electrostatic chuck 20 and the back surface (lower surface) of the substrate W.

[0048] The plasma processing apparatus 1 may further include an outer peripheral member 27. The outer peripheral member 27 extends circumferentially and radially outward relative to the substrate support 16 so as to surround the substrate support 16. The outer peripheral member 27 may also extend circumferentially and radially outward relative to the support portion 17 so as to surround the support portion 17. The outer peripheral member 27 may be composed of one or more members. The outer peripheral member 27 is formed of an insulator such as quartz.

[0049] The plasma processing apparatus 1 further includes an upper electrode 30 . The upper electrode 30 is disposed above the substrate support 16 . The upper electrode 30, together with a member 32 , closes the upper opening of the chamber body 12 . The member 32 is insulating. The upper electrode 30 is supported on the upper portion of the chamber body 12 via the member 32 .

[0050] 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 exhaust holes 34a are formed in the top plate 34. Each of the plurality of gas exhaust holes 34a penetrates the top plate 34 in the plate thickness direction (vertical direction). The top plate 34 is not limited to this and may be formed, for example, from silicon. Alternatively, the top plate 34 may have a structure in which a plasma-resistant film is formed on the surface of an aluminum component. This film may be a ceramic film such as a film formed by anodizing or a film formed from yttrium oxide.

[0051] The support body 36 detachably supports the top plate 34. The support body 36 detachably supports the top plate 34 and is formed of a conductive material such as aluminum. A gas diffusion chamber 36a is formed within the support body 36. A plurality of gas holes 36b extend downward from the gas diffusion chamber 36a. The plurality of gas holes 36b are connected to the plurality of gas exhaust holes 34a. A gas inlet 36c is formed in the support body 36. The gas inlet 36c is connected to the gas diffusion chamber 36a. A gas supply pipe 38 is connected to the gas inlet 36c.

[0052] The gas supply pipe 38 is connected to the gas source group 40 via the valve group 41, the flow controller group 42 and the valve group 43. The gas source group 40, the valve group 41, the flow controller group 42 and the valve group 43 constitute the gas supply unit GS. The gas source group 40 includes a plurality of gas sources. The valve group 41 and the valve group 43 each include a plurality of valves (such as on-off valves). The flow controller group 42 includes a plurality of flow controllers. The plurality of flow controllers of the flow controller group 42 are each a mass flow controller or a pressure-controlled flow controller. The plurality of gas sources of the gas source group 40 are each connected to the gas supply pipe 38 via a corresponding valve of the valve group 41, a corresponding flow controller of the flow controller group 42 and a corresponding valve of the valve group 43. The plasma processing apparatus 1 is capable of supplying gas from a gas source at a separately regulated flow rate to the internal space 10s, wherein the gas source is one or more gas sources selected from the plurality of gas sources of the gas source group 40.

[0053] A baffle 48 is provided between the substrate support 16 or the peripheral member 27 and the sidewall of the chamber 10. The baffle 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 48. Below the baffle 48, an exhaust pipe 52 is connected to the bottom of the chamber 10. The exhaust pipe 52 is connected to an exhaust device 50. The exhaust device 50 includes a pressure controller such as an automatic pressure control valve and a vacuum pump such as a turbomolecular pump, and is capable of reducing the pressure in the internal space 10s.

[0054] 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 electric power (hereinafter referred to as "first high-frequency electric power"). The first high-frequency electric power is used to generate plasma from the gas in the chamber 10. The first high-frequency electric power has a first frequency. The first frequency is a frequency in the 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 of the load side (upper electrode 30 side). In addition, 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 the upper electrode 30.

[0055] 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 electric power (hereinafter referred to as "second high-frequency electric power") for introducing ions from the plasma into the substrate W. The second high-frequency electric power has a second frequency. The second frequency is lower than the first frequency. The second frequency is, for example, a frequency in the 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 62 m. The matching circuit 62 m is configured to match the output impedance of the high-frequency power supply 62 with the impedance of the load side (the base 18 side).

[0056] The plasma processing apparatus 1 further includes a control unit MC. This control unit MC is a computer comprising a processor, a storage device, an input device, a display device, and the like, and controls various components of the plasma processing apparatus 1. The control unit MC executes a control program stored in the storage device and controls various components of the plasma processing apparatus 1 based on recipe data stored in the storage device. The program specified by the recipe data is executed in the plasma processing apparatus 1 under the control of the control unit MC.

[0057] Below, refer to Figures 1 to 3 as well as Figure 4 , the edge ring 22 and the substrate support 16 are described in detail. Figure 4 FIG2 is a partially enlarged cross-sectional view of an edge ring according to an exemplary embodiment. The edge ring 22 includes a first ring 221 and a second ring 222 . Figure 4 , a state in which the first ring 221 and the second ring 222 are separated from each other is shown.

[0058] The first ring 221 and the second ring 222 are each annular members and are formed of a material appropriately selected according to the plasma processing to be performed in the plasma processing apparatus 1. The first ring 221 and the second ring 222 are each formed of, for example, silicon or silicon carbide.

[0059] The first ring 221 is mounted on the second region 162 in such a manner that its central axis is located on the axis AX. In one embodiment, the first ring 221 is disposed in 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. In addition, the first ring 221 may be mounted on a component other than the electrostatic chuck 20 in the second region 162. In one embodiment, as Figure 4 As shown, the first ring 221 includes an inner region (inner portion) 221i, a loading region (middle portion) 221m, and an outer region (outer portion) 221o. The inner region 221i, the loading region 221m, and the outer region 221o are each annular regions extending around the central axis of the first ring 221.

[0060] like Figures 1 to 3As shown, the inner peripheral region 221i is provided closer to the central axis of the first ring 221 than the loading region 221m and the outer peripheral region 221o, and extends in the circumferential direction. The outer peripheral region 221o extends radially outward relative to the inner peripheral region 221i and the loading region 221m. In a state where the substrate W is placed on the electrostatic chuck 20, the edge of the substrate W extends on or above the inner peripheral region 221i. The outer peripheral region 221o is radially outward from the edge of the substrate W.

[0061] The loading region 221m extends in the circumferential direction between the inner peripheral region 221i and the outer peripheral region 221o. The through holes 221h are formed in the loading region 221m. The through holes 221h are formed in the loading region 221m in a manner extending along the vertical direction. In one embodiment, a plurality of through holes 221h are formed in the loading region 221m. The number of the through holes 221h can be the same as the number of the lift pins 72 of the lift mechanism 70.

[0062] Each of the through holes 221h has a size in which the following-described first cylindrical portion 721 of the corresponding lift pin 72 cannot be inserted, but the following-described second cylindrical portion 722 of the corresponding lift pin 72 can be inserted. In a case where each of the through holes 221h has a cylindrical shape at the first cylindrical portion 721 and the second cylindrical portion 722, the diameter is smaller than that of the first cylindrical portion 721, and slightly larger than that of the second cylindrical portion 722 (or the following-described first portion 722a). The first ring 221 is arranged on the second region 162 in a manner in which each of the through holes 221h and the corresponding lift pin 72 are aligned in a straight line.

[0063] The upper surface of the loading region 221m extends at a position lower in the height direction than the upper surface of the inner peripheral region 221i and the upper surface of the outer peripheral region 221o. Therefore, the first ring 221 draws a recess on the loading region 221m. The second ring 222 is loaded on the loading region 221m in a manner of being fitted into the recess on the loading region 221m. In a state where the substrate W is placed on the electrostatic chuck 20, the inner peripheral surface of the second ring 222 faces the end surface of the substrate W.

[0064] 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 circumferential surface, and an outer circumferential 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 circumferential surface, and an outer circumferential surface. The lower surface of the inner portion 221i, the lower surface of the middle portion 221m, and the lower surface of the outer portion 221o form a single horizontal surface on the lower surface of the first ring 221. Furthermore, the upper surface of the inner portion 221i is located higher than the upper surface of the middle portion 221m, and the upper surface of the outer portion 221o is located higher than the upper surfaces of the inner portion 221i and the upper surfaces of the middle portion 221m. That is, the inner portion 221i has a thickness smaller than that of the outer portion 221o in the vertical direction. Furthermore, the middle portion 221m has a thickness smaller than both the inner portion 221i and the outer portion 221o in the vertical direction. The substrate support area 2a of the main body 2 has an area smaller than that of the substrate W, and the upper surface of the inner portion 221i faces a portion of the back surface of the substrate W on the substrate support area 2a. The inner circumferential surface of the inner portion 221i faces the side wall 2c of the main body 2. The outer circumferential surface of the inner portion 221i is connected to the inner circumferential end of the upper surface of the middle portion 221m. The inner circumferential surface of the outer portion 221o is connected to the outer circumferential end of the upper surface of the middle portion 221m. That is, the first ring 221 has a recess defined by the outer circumferential surface of the inner portion 221i, the upper surface of the middle portion 221m, and the inner circumferential surface of the outer portion 221o.

[0065] The lower surface of the second ring 222 is substantially flat. Figure 4 As shown, the lower surface of the second ring 222 further includes a tapered surface that 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 recesses 222r in the second ring 222 can be the same as the number of lift pins 72 of the lift mechanism 70. Each recess 222r has a size that allows the tip of the second columnar portion 722 of the corresponding lift pin 72 to fit therein. The second ring 222 is arranged on the loading area 221m such that each recess 222r, the corresponding lift pin 72, and the corresponding through-hole 221h are aligned.

[0066] In one embodiment, the second ring 222 is housed in the recessed portion of the first ring 221. Specifically, 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 so that, when disposed on the annular region 2b, the upper surface of the outer portion 221o of the first ring 221 and the upper surface of the second ring 222 are approximately the same height as the upper surface of the substrate W on the substrate support region 2a. Furthermore, the second ring 222 has an inner circumferential surface 222a that faces the end 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.

[0067] like Figures 1 to 3 As shown, the substrate support 16 further includes a lifting mechanism 70. The lifting mechanism 70 includes lifting pins 72 that can lift and lower the first ring 221 and the second ring 222. In one embodiment, the lifting mechanism 70 includes a plurality of lifting pins 72. The number of lifting pins 72 in the lifting mechanism 70 can be any number as long as the edge ring 22 can be supported and raised and lowered. For example, the number of lifting pins 72 in the lifting mechanism 70 is three.

[0068] Each lift pin 72 can be formed from an insulating material. Each lift pin 72 can 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 vertically. The first columnar portion 721 has a first upper end surface 721t. The first upper end surface 721t is capable of contacting the lower surface of the first ring 221.

[0069] The second columnar portion 722 extends vertically above the first columnar portion 721. The second columnar portion 722 is narrower than the first columnar portion 721 so that the first upper end surface 721t is exposed. 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 can move up and down through the through-hole 221h of the loading area 221m. The vertical length of the second columnar portion 722 is greater than the vertical thickness of the loading area 221m.

[0070] The second columnar portion 722 has a second upper end surface 722t that can abut against the second ring 222. In one embodiment, the front end of the second columnar portion 722 including the second upper end surface 722t can be formed into a tapered shape so as to fit into the corresponding recess 222r.

[0071] 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 upper end surface 722t. In this embodiment, the width of the first portion 722a is greater than the width of the second portion 722b.

[0072] In one embodiment, the first columnar portion 721, the first portion 722a, and the second portion 722b may have a cylindrical shape. In this embodiment, the diameter of the first columnar portion 721 is larger than the diameter of the first portion 722a, and the diameter of the first portion 722a is larger than the diameter of the second portion 722b.

[0073] In one embodiment, the second columnar portion 722 may further include a third portion 722c. The third portion 722c extends between the first portion 721a and the second portion 722b. In this embodiment, the third portion 722c has a tapered surface.

[0074] In one embodiment, the lifting mechanism 70 includes one or more driving devices 74. The one or more driving devices 74 are configured to be able to lift and lower the plurality of lifting pins 72. Each of the one or more driving devices 74 may include, for example, an electric motor.

[0075] In one embodiment, Figure 2 As shown, the plasma processing apparatus 1 may further include another gas supply unit 76. The gas supply unit 76 supplies gas to each through hole 162h to prevent discharge in each through hole 162h. The gas supplied from the gas supply unit 76 to each through hole 162h is an inert gas. For example, the gas supplied from the gas supply unit 76 to each through hole 162h is helium.

[0076] In one embodiment, the lower rod 721 has a first upper end surface 721t capable of abutting against the first ring 221. In addition, the upper rod 722 extends upward from the first upper end surface 721t of the lower rod 721, can abut against the second ring 222 via the through hole 221h of the first ring 221, and has a length greater than the length of the through hole 221h.

[0077] In one embodiment, the upper rod 722 is thinner than the lower rod 721 .

[0078] 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 .

[0079] In one embodiment, the upper rod 722 includes 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 second upper end surface 722t. The first portion 722a is thicker than the second portion 722b.

[0080] In one embodiment, the lower rod 721 , the first portion 722 a , and the second portion 722 b have a cylindrical shape, and the first portion 722 a has a diameter smaller than that of the lower rod 721 and larger than that of the second portion 722 b .

[0081] In one embodiment, the upper rod 722 includes a tapered third portion 722c between the first portion 722a and the second portion 722b.

[0082] In one embodiment, the second ring 222 has a recess 222 r into which the second upper end surface 722 t of the upper rod 722 is fitted.

[0083] Below, refer to Figures 5 to 8 . Figures 5 to 8 Each is an enlarged view of a portion of a substrate support according to an exemplary embodiment. Figures 5 to 8 In each of the figures, the substrate support is shown in a partially cut-away state. Figure 5 3 shows a state where only the second ring 222 is arranged above the substrate support 16 . Figure 6 3 shows a state in which the first upper end surface 721 t of the lift pin 72 abuts against the first ring 221 . Figure 7 3 shows a state where the first ring 221 and the second ring 222 are arranged above the substrate support 16 . Figure 8 3 shows a state where the first ring 221 and the second ring 222 are transferred from the lift pins 72 of the lift mechanism 70 to the transport robot.

[0084] like Figure 5 As shown, according to the substrate support 16, while the first upper end surface 721t of each lift pin 72 is not in contact with the first ring 221, the lift mechanism 70 can be used to lift and lower only the second ring 222, which is in contact with the second upper end surface 722t of each lift pin 72. By adjusting only the height position of the second ring 222 using 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 at the edge of the substrate W can be adjusted.

[0085] Alternatively, the second ring 222 is moved upward from the substrate support 16 by the lifting mechanism 70, and the second ring 222 is delivered to the processing portion of the transport robot via the plurality of lift pins 72. The transport robot can then transport the second ring 222 out of the chamber 10. Thereafter, the transport robot transports a new second ring 222 into the chamber 10, and the lifting mechanism 70 can be used to place the new second ring 222 on the loading area 221 m.

[0086] In one embodiment, the second ring 222 is disposed in a recessed portion on the loading area 221m. According to this embodiment, the positioning accuracy of the second ring 222 relative to the first ring 221 and the substrate support 16 is improved.

[0087] 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 horizontal movement of the second ring 222 relative to the lift pins 72. Consequently, the positioning accuracy of the second ring 222 relative to the lift pins 72 is improved, resulting in improved positioning accuracy of the second ring 222 on the first ring 221 and the substrate support 16.

[0088] When the plurality of lift pins 72 supporting the second ring 222 are further moved upward, as shown in FIG. Figure 6 As shown in FIG. 2 , the first upper end surface 721t of each lift pin 72 abuts against the first ring 221. That is, when the plurality of lift pins 72 are further moved upward, a state is formed in which the first upper end surface 721t abuts against the first ring 221 and the second upper end surface 722t abuts against the second ring 222. In this state, as shown in FIG. Figure 7 As shown, the first ring 221 and the second ring 222 can be simultaneously raised and lowered above the substrate support 16 by the lifting mechanism 70. Therefore, according to the substrate support 16, only one of the two rings constituting the edge ring 22 can be raised and lowered, or both rings can be raised and lowered simultaneously using a relatively small number of lift pins 72.

[0089] Then, if Figure 8 As shown, by moving the processing section of the transport robot TR below the edge ring 22 and moving the plurality of lift pins 72 downward, the edge ring 22 can be transferred from the plurality of lift pins 72 to the processing section of the transport robot TR. The transport robot TR can then transport the edge ring 22 out of the chamber 10. After one or both of the first ring 221 and the second ring 222 have been replaced with new ones, the transport robot TR can transport the edge ring 22 into the chamber 10 and position it on the second area 162 using the lift mechanism 70.

[0090] In one embodiment, as described above, the second columnar portion 722 of each lift pin 72 includes 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. Figure 7 As shown, the first ring 221 is supported by the lift pins 72 with the first portion 722a partially positioned within the through-hole 221h. The first portion 722a is the wider portion of the second columnar portion 722. Therefore, horizontal movement of the first ring 221 relative to the lift pins 72 is suppressed. Consequently, the positioning accuracy of the first ring 221 on the substrate support 16 is improved.

[0091] Below, refer to Figure 9 Method MT including cleaning of an edge ring is described. Figure 9 1 is a flowchart of a method according to an exemplary embodiment including cleaning of an edge ring. Next, the control of each component of the plasma processing apparatus 1 by the control unit MC for executing the method MT will be described.

[0092] In one embodiment, Figure 9 The method shown can be performed when replacing one or both of the first ring 221 and the second ring 222 with new parts. The first ring 221 and the second ring 222 are replaced when they are consumed as a result of plasma processing performed in the plasma processing apparatus 1 and need to be replaced.

[0093] The control unit MC may determine that the first ring 221 needs to be replaced when the length of time the first ring 221 has been used for plasma processing is equal to or longer than a first reference time length. The control unit MC may determine that the second ring 222 needs to be replaced when the length of time the second ring 222 has been used for plasma processing is equal to or longer than a second reference time length. The second reference time length may be a time length shorter than the first reference time length.

[0094] Alternatively, the control unit MC may determine that the first ring 221 needs to be replaced when the thickness of the first ring 221 detected by the optical sensor is less than or thinner than a first reference thickness. The control unit MC may also determine that the second ring 222 needs to be replaced when the thickness of the second ring 222 detected by the optical sensor is less than or thinner than a second reference thickness. The optical sensor may be an optical interferometer.

[0095] Alternatively, the control unit MC may determine that the first ring 221 needs to be replaced 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 equal to or less than a first reference torque. Alternatively, the control unit MC may determine that both the first ring 221 and the second ring 222 need to be replaced 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 equal to or less than a reference torque. The control unit MC may determine that the second ring 222 needs to be replaced 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 equal to or less than a second reference torque.

[0096] In step ST1 of method MT, the second ring 222 or the edge ring 22, that is, both the first ring 221 and the second ring 222, are supported by the plurality of lift pins 72 and lifted upward from the substrate support 16. In step ST1, the control unit 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. The result of executing step ST1 is as follows: Figure 6 As shown in FIG. 1 , the second ring 222 is positioned above the substrate support 16. Alternatively, the result of executing step ST1 is as follows: Figure 7 As shown, both the first ring 221 and the second ring 222 are positioned upward relative to the substrate support 16 .

[0097] In the next step ST2, Figure 6 or Figure 7 In the state shown, plasma is formed from the cleaning gas in the chamber 10. Then, the second ring 222 or the edge ring 22 is cleaned using chemical species from the plasma. By 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, that is, the high-frequency power supply 61 and / or the high-frequency power supply 62, in order to generate plasma from the cleaning gas in the chamber 10.

[0098] In the next step ST3, the second ring 222 or edge ring 22 is transported out of the chamber 10 using a transport robot. The transport robot can be controlled by the control unit MC. Through the cleaning process in step ST2, substances adhering to the second ring 222 or edge ring 22 are removed. This prevents contamination of the transport path of the second ring 222 or edge ring 22 outside the chamber 10.

[0099] In the following step ST4, a replacement component corresponding to one or both of the first ring 221 and the second ring 222 is transported into the chamber 10 by the transport robot. The replacement component can be a new, unused component. The replacement component is then transferred from the handling portion of the transport robot to the plurality of lift pins 72 of the lift mechanism 70. The plurality of lift pins 72 are then lowered, and the replacement component is loaded onto the substrate support 16. In step ST4, the transport robot and the drive device 74 of the lift mechanism 70 can be controlled by the control unit MC.

[0100] In one embodiment, the control unit MC controls the driving device 74 so that the lift pins 72 lift either the first and second rings 221 and 222 or the second ring 222 from the substrate support 16. For example, the control unit MC controls the driving device 74 so that the lift pins 72 lift both the first and second rings 221 and 222 from the substrate support 16. Alternatively, for example, the control unit MC controls the driving device 74 so that the lift pins 72 lift only the second ring 222 from the substrate support 16 while the first ring 221 remains on the substrate support 16.

[0101] In one embodiment, the control unit MC controls the gas supply unit GS and the energy source (high-frequency power supply 61) to supply a clean gas into the chamber 10 and generate plasma from the clean gas. This control is performed while the first and second rings 221 and 222, or the second ring 222, are lifted from the substrate support 16. For example, the control is performed while both the first and second rings 221 and 222 are lifted from the substrate support 16. Alternatively, the control is performed while the second ring 222 is lifted from the substrate support 16 while the first ring 221 remains on the substrate support 16.

[0102] Although various exemplary embodiments have been described above, the present invention is not limited to the exemplary embodiments described above, and various omissions, substitutions, and changes can be made. In addition, elements of different exemplary embodiments can be appropriately combined to form other exemplary embodiments.

[0103] For example, a recess may be formed on one of the first ring 221 and the second ring 222, and a projection that can fit into the recess may be formed on the other. In this case, the positioning accuracy of the first ring 221 and the second ring 222 is improved.

[0104] However, the plasma processing apparatus including the substrate support 16 is not limited to the plasma processing apparatus 1. The plasma processing apparatus including the substrate support 16 may be a capacitively coupled plasma processing apparatus different from the plasma processing apparatus 1. Alternatively, the plasma processing apparatus including the substrate support 16 may be another type of plasma processing apparatus. Examples of such a type 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.

[0105] Based on the above description, various embodiments of the present invention have been described in this specification for illustrative purposes. It should be understood that various modifications can be made without departing from the scope and spirit of the present invention. Therefore, the various embodiments disclosed in this specification are not intended to be limiting, and the true scope and spirit are set forth in the appended patent claims.

Claims

1. A substrate support, characterized in that: include: a main body portion having a substrate supporting area and an annular area, the annular area surrounding the substrate supporting area; a first ring having a through hole and disposed on the annular region; a second ring disposed on the first ring, the second ring having an inner peripheral surface facing an end surface of the substrate on the substrate supporting area; and The lifting pin includes a lower rod and an upper rod, wherein the lower rod has an upper end surface capable of abutting against the first ring, and 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 the upper rod has a length greater than the length of the through hole. The first ring includes an inner peripheral area, an outer peripheral area, and an intermediate loading area located between the inner peripheral area and the outer peripheral area and having the through hole formed therein. The upper surface of the intermediate loading area is set lower than the upper surfaces of the inner peripheral area and the outer peripheral area. The first ring has a recess formed in the intermediate loading area, and the second ring is arranged above the intermediate loading area and fitted into the recess.

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

3. The substrate support according to claim 1 or 2, wherein: The lower rod and the upper rod each have a cylindrical shape, The diameter of the lower rod is larger than the diameter of the upper rod.

4. The substrate support according to claim 3, wherein: The upper side rod has: A first portion extending upward from the lower rod; and a second portion including a front end portion extending upward from the first portion, The first portion is thicker than the second portion.

5. The substrate support according to claim 4, wherein: The lower rod, the first portion and the second portion have a cylindrical shape, The first portion has a diameter that is smaller than a diameter of the lower rod and larger than a diameter of the second portion.

6. The substrate support according to claim 5, wherein: The upper rod further has a tapered portion between the first portion and the second portion.

7. The substrate support according to claim 6, wherein: The second ring has a recessed portion into which the front end portion of the upper rod is fitted.

8. The substrate support according to claim 1 or 2, wherein: The main body includes a base and an electrostatic chuck configured on the base.

9. A plasma processing device, characterized in that: include: chamber; A substrate support according to any one of claims 1 to 8, disposed in the chamber; and The driving device is configured to be able to move the lifting pin up and down.

10. The plasma processing apparatus according to claim 9, wherein include: a gas supply unit configured to supply a cleaning gas into the chamber; an energy source configured to supply energy for generating plasma from the cleaning gas within the chamber; and Control Department, The control unit performs the following control, namely: controlling the driving device so that the lifting pins lift the first ring and the second ring or the second ring from the substrate support, The gas supply unit and the energy source are controlled so that the cleaning gas is supplied into the chamber and plasma is generated from the cleaning gas while the first ring and the second ring or the second ring is lifted from the substrate support.

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