Mounting table and plasma processing apparatus

Abstract

A mounting table includes an electrostatic chuck for supporting a substrate and an edge ring, and a susceptor for supporting the electrostatic chuck, the electrostatic chuck having: a first region having a first upper surface and capable of supporting a substrate placed on the first upper surface, and a second region having a second upper surface and capable of supporting a substrate placed on the first upper surface; a second region having a second upper surface, provided integrally with the periphery of the first region, and capable of supporting an edge ring placed on the second upper surface; a first electrode provided in the first region for applying a DC voltage; a second electrode provided in the second region for applying a DC voltage; and a third electrode for applying bias electric power. According to the present invention, discharge of the heat transfer gas supplied between the lower surface of the substrate and the upper surface of the electrostatic chuck can be suppressed.

Description

[0001] This application is a divisional application of a patent application with an application date of June 8, 2020, application number 202010511103.X, and invention name “Carrying table and plasma processing device”. Technical Field

[0002] The present invention relates to a mounting table and a plasma processing device. Background Art

[0003] A plasma processing apparatus is used in the manufacture of electronic devices. The plasma processing apparatus excites a gas supplied into a chamber by applying high-frequency electric power to a mounting table to generate plasma, thereby performing plasma processing on a substrate on the mounting table.

[0004] In recent years, plasma processing has been performed under high power conditions, especially for high frequencies used for ion introduction (biasing). In this regard, for example, Patent Document 1 discloses a technique for reducing the energy of ions irradiated onto the inner wall of a chamber body.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent document 1: Japanese Patent Application Publication No. 2019-36658. Summary of the invention

[0008] When plasma processing is performed under high-power conditions for high-frequency ion introduction, ionization may occur in the heat transfer gas supplied between the lower surface of the substrate and the upper surface of the electrostatic chuck, thereby generating discharge.

[0009] An object of the present invention is to provide a mounting table and a plasma processing apparatus capable of suppressing discharge of a heat transfer gas supplied between a lower surface of a substrate and an upper surface of an electrostatic chuck.

[0010] According to one embodiment of the present invention, there is provided a stage, comprising an electrostatic chuck for supporting a substrate and an edge ring and a base for supporting the electrostatic chuck, wherein the electrostatic chuck comprises: a first region having a first upper surface capable of supporting a substrate placed on the first upper surface; a second region having a second upper surface and being arranged to be integrated with the periphery of the first region and capable of supporting an edge ring placed on the second upper surface; a first electrode for applying a DC voltage arranged in the first region; a second electrode for applying a DC voltage arranged in the second region; and a third electrode for applying bias power.

[0011] According to one aspect, discharge of the heat transfer gas supplied between the lower surface of the substrate and the upper surface of the electrostatic chuck can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic cross-sectional view showing an example of a plasma processing apparatus according to one embodiment.

[0013] Figure 2 This is a diagram showing an example of a mounting table according to an embodiment.

[0014] Figure 3 The figures are views showing the AA cross section, the BB cross section, and the CC cross section of the mounting table according to one embodiment.

[0015] Description of Reference Numerals

[0016] 1: plasma processing device, 10: chamber, 14: mounting table, 16: electrode plate, 18: lower electrode, 20: electrostatic suction cup, 20a: first region, 20b: second region, 21, 25: bias electrode, 26: edge ring, 23, 27a, 27b: adsorption electrode, 61: first high-frequency power supply, 62: second high-frequency power supply, 65: third high-frequency power supply, 201: first upper surface, 202: second upper surface, W: substrate. DETAILED DESCRIPTION

[0017] Hereinafter, the mode for implementing the present invention will be described with reference to the drawings. In each of the drawings, the same components are sometimes denoted by the same reference numerals, and duplicate descriptions are omitted.

[0018] [Plasma processing device]

[0019] Figure 1 This is a diagram schematically showing a plasma processing apparatus according to an embodiment. Figure 1 The plasma processing apparatus 1 shown is a capacitive coupling type apparatus. The plasma processing apparatus 1 has a chamber 10. The chamber 10 provides an internal space 10s therein.

[0020] The chamber 10 includes a chamber body 12. The chamber body 12 has a substantially cylindrical shape. An internal space 10s is provided inside the chamber body 12. The chamber body 12 is formed of, for example, aluminum. A corrosion-resistant film is provided on the inner wall surface of the chamber body 12. The corrosion-resistant film can be a film formed of ceramics such as aluminum oxide and yttrium oxide.

[0021] A passage 12p is formed in the side wall of the chamber body 12. The substrate W passes through the passage 12p when being transported between the internal space 10s and the outside of the chamber 10. The passage 12p can be opened and closed by a gate valve 12g. The gate valve 12g is provided along the side wall of the chamber body 12.

[0022] A support portion 13 is provided on the bottom of the chamber body 12. The support portion 13 is formed of an insulating material. The support portion 13 has a substantially cylindrical shape. The support portion 13 extends upward from the bottom of the chamber body 12 in the internal space 10s. A component 15 is provided on the support portion 13. The component 15 may also be formed of an insulator such as quartz. The component 15 may have a substantially cylindrical shape. Alternatively, the component 15 may be a plate-like body having a ring shape.

[0023] The plasma processing apparatus 1 further includes a substrate mounting table, that is, a mounting table 14 in an exemplary embodiment. The mounting table 14 is supported by the support portion 13. The mounting table 14 is disposed in the internal space 10s. The mounting table 14 is configured to support the substrate W in the chamber 10, that is, in the internal space 10s.

[0024] The mounting table 14 has a lower electrode 18 and an electrostatic chuck 20 of an exemplary embodiment. The mounting table 14 may further have an electrode plate 16. The electrode plate 16 is formed of a conductor such as aluminum, and has a substantially disc shape. The lower electrode 18 is disposed on the electrode plate 16. The lower electrode 18 is formed of a conductor such as aluminum, and has a substantially disc shape. The lower electrode 18 is electrically connected to the electrode plate 16. The outer peripheral surface of the lower electrode 18 and the outer peripheral surface of the electrode plate 16 are surrounded by the support portion 13. The electrode plate 16 and the lower electrode 18 are an example of a base that supports the electrostatic chuck 20.

[0025] The electrostatic chuck 20 is disposed on the lower electrode 18. The edge of the electrostatic chuck 20 and the edge ring 26 are surrounded by the member 15. The electrostatic chuck 20 supports the substrate W and the edge ring 26 in an exemplary embodiment.

[0026] The substrate W has a disk shape, for example, and is placed on the electrostatic chuck 20. The edge ring 26 is placed on the electrostatic chuck 20 so as to surround the edge of the substrate W. The outer edge of the edge ring 26 may be extended on the component 15. The edge ring 26 is a component having an annular shape. The edge ring 26 can be formed of silicon, silicon carbide, or quartz without limitation. The edge ring 26 is also called a focus ring.

[0027] A flow path 18f is provided inside the lower electrode 18. A heat exchange medium (e.g., a refrigerant) is supplied to the flow path 18f from a refrigeration unit 22 provided outside the chamber 10 via a pipe 22a. The heat exchange medium supplied to the flow path 18f returns to the refrigeration unit 22 via a pipe 22b. In the plasma processing apparatus 1, the temperature of the substrate W placed on the electrostatic chuck 20 can be adjusted by heat exchange between the heat exchange medium and the lower electrode 18.

[0028] The plasma processing apparatus 1 is provided with a gas supply line 24. The gas supply line 24 supplies a heat transfer gas (eg, He gas) from a heat transfer gas supply mechanism to a space between the upper surface of the electrostatic chuck 20 and the lower surface of the substrate W.

[0029] The plasma processing apparatus 1 further includes an upper electrode 30. The upper electrode 30 is disposed above the mounting table 14. The upper electrode 30 is supported on the upper portion of the chamber body 12 by a member 32. The member 32 is formed of an insulating material. The upper electrode 30 and the member 32 close the upper opening of the chamber body 12.

[0030] The upper electrode 30 may include a top plate 34 and a support body 36. The lower surface of the top plate 34 is the lower surface on one side of the internal space 10s, and divides the internal space 10s. The top plate 34 may be formed of a low-resistance conductor or semiconductor with little Joule heat. A plurality of gas exhaust holes 34a are formed in the top plate 34. The plurality of gas exhaust holes 34a penetrate the top plate 34 in the plate thickness direction of the top plate 34.

[0031] The support body 36 detachably supports the top plate 34. The support body 36 is formed of a conductive material such as aluminum. A gas diffusion chamber 36a is provided inside the support body 36. A plurality of gas holes 36b are formed in the support body 36. The plurality of gas holes 36b extend downward from the gas diffusion chamber 36a. The plurality of gas holes 36b connect the plurality of gas discharge holes 34a, respectively. 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.

[0032] The gas supply pipe 38 is connected to a gas supply unit GS. The gas supply unit GS includes a gas source group 40, a valve group 41, a flow controller group 42 and a valve group 43. The gas source group 40 is connected to the gas supply pipe 38 via the valve group 41, the flow controller group 42 and the valve group 43. The gas source group 40 includes a plurality of gas sources. The valve group 41 and the valve group 43 include a plurality of opening and closing valves, respectively. The flow controller group 42 includes a plurality of flow controllers. The plurality of flow controllers of the flow controller group 42 are respectively mass flow controllers or pressure-controlled flow controllers. The plurality of gas sources of the gas source group 40 are connected to the gas supply pipe 38 via the corresponding opening and closing valves of the valve group 41, the corresponding flow controllers of the flow controller group 42 and the corresponding opening and closing valves of the valve group 43, respectively.

[0033] In the plasma processing apparatus 1, a protective plate 46 is detachably provided along the inner wall surface of the chamber body 12. The protective plate 46 is also provided on the outer periphery of the support portion 13. The protective plate 46 prevents reaction products such as etching byproducts from adhering to the chamber body 12. The protective plate 46 is formed, for example, by forming a corrosion-resistant film on the surface of a member formed of aluminum. The corrosion-resistant film can be a film formed of ceramics such as yttrium oxide.

[0034] A partition 48 is provided between the support portion 13 and the side wall of the chamber body 12. The partition 48 is formed by, for example, forming a corrosion-resistant film on the surface of a member formed of aluminum. The corrosion-resistant film can be a film formed of ceramics such as yttrium oxide. A plurality of through holes are formed in the partition 48. An exhaust port 12e is provided below the partition 48 and at the bottom of the chamber body 12. An exhaust device 50 is connected to the exhaust port 12e via an exhaust pipe 52. The exhaust device 50 includes a pressure regulating valve and a vacuum pump such as a turbomolecular pump.

[0035] The plasma processing apparatus 1 includes a first high frequency power source 61 for applying high frequency HF power for plasma generation. The first high frequency power source 61 is configured to generate high frequency HF power to generate plasma from gas in the chamber 10. The frequency of the high frequency HF is, for example, in the range of 27 MHz to 100 MHz.

[0036] The first high frequency power source 61 is electrically connected to the lower electrode 18 via a matching device 63. The matching device 63 has a matching circuit. The matching circuit of the matching device 63 is configured to match the impedance of the load side (lower electrode side) of the first high frequency power source 61 with the output impedance of the first high frequency power source 61. In another embodiment, the first high frequency power source 61 may also be electrically connected to the upper electrode 30 via the matching device 63.

[0037] The plasma processing device 1 may further include a second high-frequency power supply 62 for applying high-frequency LF electric power for ion introduction. The second high-frequency power supply 62 is configured to generate high-frequency LF electric power. The high-frequency LF mainly has a frequency suitable for introducing ions into the substrate W, for example, a frequency in the range of 400kHz to 13.56MHz. Alternatively, the high-frequency LF may also be a pulsed voltage having a rectangular waveform.

[0038] The second high frequency power source 62 is electrically connected to the bias electrode 21 in the electrostatic chuck 20 via the matching device 64. The matching device 64 has a matching circuit. The matching circuit of the matching device 64 is configured to match the impedance of the load side (lower electrode side) of the second high frequency power source 62 with the output impedance of the second high frequency power source 62.

[0039] The plasma processing device 1 may further include a control unit 80. The control unit 80 may be a computer including a processor, a storage unit such as a memory, an input device, a display device, a signal input and output interface, and the like. The control unit 80 controls each unit of the plasma processing device 1. In the control unit 80, an operator can use the input device to input commands for managing the plasma processing device 1. In addition, in the control unit 80, the working status of the plasma processing device 1 can be visually displayed using a display device. Furthermore, a control program and processing scheme data are stored in the storage unit of the control unit 80. In order to perform various processes in the plasma processing device 1, the control program is executed by the processor of the control unit 80. The control program is executed by the processor of the control unit 80 to control each unit of the plasma processing device 1 according to the processing scheme data, and various process flows, such as plasma processing methods, are performed in the plasma processing device 1.

[0040] [Putting table]

[0041] Hereinafter, the mounting table 14 according to one embodiment will be described in detail. Figure 1 At the same time refer to Figure 2 . Figure 2 It is a cross-sectional view showing the mounting table 14 according to one embodiment.

[0042] The electrostatic chuck 20 has a main body. The main body of the electrostatic chuck 20 has a substantially disk shape. The main body of the electrostatic chuck 20 is formed of a dielectric material. The main body of the electrostatic chuck 20 includes a first region 20a and a second region 20b.

[0043] The first region 20a is a region having a substantially disk shape. The first region 20a has a first upper surface 201. The first region 20a is configured to be able to hold the substrate W placed on the first upper surface 201. The diameter of the first region 20a is smaller than the diameter of the substrate W.

[0044] The second region 20b is a ring-shaped region. The second region 20b and the first region 20a share a central axis (at Figure 2 The second region 20b has a second upper surface 202. The second region 20b is provided so as to be integrated with the periphery of the first region 20a and is configured to support the edge ring 26 mounted on the second upper surface 202 (see Figure 1 ).

[0045] The main body of the electrostatic chuck 20, i.e., the first region 20a and the second region 20b, can be formed of a single dielectric material. That is, the dielectric material constituting the first region 20a and the dielectric material constituting the second region 20b can be the same. For example, the main body of the electrostatic chuck 20 is formed of ceramics such as aluminum oxide and aluminum nitride. In the electrostatic chuck 20, the second upper surface 202 of the second region 20b is lower than the first upper surface 201 of the first region 20a, and the thickness of the first region 20a is thicker than the thickness of the second region 20b.

[0046] The electrostatic chuck 20 also has an adsorption electrode 23. The adsorption electrode 23 is provided in the first region 20a. The adsorption electrode 23 is connected to the DC power supply 20p via the switch 20s. When a DC voltage from the DC power supply 20p is applied to the adsorption electrode 23, an electrostatic attraction is generated between the first region 20a and the substrate W. Due to the generated electrostatic attraction, the substrate W is attracted to the first region 20a and is held by the first region 20a. The adsorption electrode 23 is provided in the first region 20a and is an example of a first electrode to which a DC voltage is applied.

[0047] The electrostatic chuck 20 also has an adsorption electrode 27a and an adsorption electrode 27b (hereinafter, sometimes collectively referred to as the adsorption electrode 27). The adsorption electrode 27a and the adsorption electrode 27b are arranged in the second region 20b. The adsorption electrode 27a and the adsorption electrode 27b are arranged to extend in the circumferential direction relative to the central axis of the electrostatic chuck 20. The adsorption electrode 27b is arranged on the outside of the adsorption electrode 27a. The adsorption electrode 27a is electrically connected to the DC power supply 20m via the switch 20n, and the adsorption electrode 27b is electrically connected to the DC power supply 20r via the switch 20t. A DC voltage is applied to the adsorption electrode 27a and the adsorption electrode 27b from the DC power supply 20m and the DC power supply 20r, respectively, in such a manner that a potential difference is generated between the adsorption electrode 27a and the adsorption electrode 27b. For example, the polarity of the DC voltage applied from the DC power supply 20m to the adsorption electrode 27a may also be the opposite polarity to the polarity of the DC voltage applied from the DC power supply 20r to the adsorption electrode 27b. However, the adsorption electrode 27 is not limited to a bipolar electrode, and may be a monopolar electrode. When a DC voltage is applied from the DC power supplies 20m and 20r to the adsorption electrode 27a and the adsorption electrode 27b, respectively, an electrostatic attraction is generated between the second region 20b and the edge ring 26. Due to the generated electrostatic attraction, the edge ring 26 is attracted to the second region 20b and is held by the second region 20b. The adsorption electrode 27a and the adsorption electrode 27b are provided in the second region 20b, and are an example of a second electrode to which a DC voltage is applied.

[0048] The bias electrode 21 is provided below the adsorption electrode 23 in the first region 20a. The bias electrode 25 is provided below the adsorption electrode 27a and the adsorption electrode 27b in the second region 20b. The third high-frequency power supply 65 is electrically connected to the bias electrode 25 in the second region 20b via the matching device 66. The matching device 66 has a matching circuit. The matching circuit of the matching device 66 is configured to match the impedance of the load side (lower electrode side) of the third high-frequency power supply 65 with the output impedance of the third high-frequency power supply 65.

[0049] Bias power for ion introduction is applied to the bias electrode 21 and the bias electrode 25. The bias power is applied by direct current voltage or high frequency voltage. Figure 1 and Figure 2 In the example of , the bias electrode 25 is applied with bias power by the high frequency voltage from the third high frequency power supply 65, but it is not limited to this, and the bias power may also be applied by the DC voltage from the DC power supply. When the bias power is applied to the bias electrode 21, the ions in the plasma are introduced into the first region 20a. Thus, the process characteristics such as the etching rate and the film forming rate in the entire surface of the substrate W can be controlled. When the bias power is applied to the bias electrode 25, the ions in the plasma are introduced into the second region 20b. Thus, the process characteristics of the edge region of the substrate W can be controlled.

[0050] The bias electrode 21 and the bias electrode 25 are examples of the third electrode to which the bias electric power is applied, the bias electrode 21 is an example of the 3-1 electrode provided in the first region 20a, and the bias electrode 25 is an example of the 3-2 electrode provided in the second region 20b. The bias electric power applied to the bias electrode 21 and the bias electrode 25 can be controlled independently of each other by the second high frequency power supply 62 and the third high frequency power supply 65. The third electrode has at least the bias electrode 21, and may not have the bias electrode 25.

[0051] The adsorption electrode 23 in the first region 20a is provided between the first upper surface 201 and the bias electrode 21. The adsorption electrode 23 and the bias electrode 21 have circular shapes having substantially the same diameter. The adsorption electrode 27a and the adsorption electrode 27b in the second region 20b are provided between the second upper surface 202 and the bias electrode 25. The adsorption electrode 27a, the adsorption electrode 27b and the bias electrode 21 have an annular shape. The radial widths of the adsorption electrode 27a and the adsorption electrode 27b are substantially the same, and the radial width of the bias electrode 21 is greater than the total radial width of the adsorption electrode 27a and the adsorption electrode 27b.

[0052] The bias electrode 21 and the adsorption electrodes 27a and 27b are arranged on the same plane of the electrostatic chuck 20. The thickness D1 from the first upper surface 201 to the upper surface of the bias electrode 21 is equal to the thickness D2 from the second upper surface 202 to the upper surface of the bias electrode 25.

[0053] [Reason for installing the bias electrode inside the electrostatic chuck]

[0054] The reason for setting the bias electrode 21 and the bias electrode 25 in the electrostatic chuck 20 is described. In recent years, plasma processing is performed under high-power conditions, especially for the high-frequency LF for ion introduction. When the high-power high-frequency LF is applied to the electrode plate 16, a potential difference is generated between the electrode plate 16 and the substrate W and between the electrode plate 16 and the edge ring 26, accompanied by the electrostatic capacitance between the electrode plate 16 and the substrate W and the electrostatic capacitance between the electrode plate 16 and the edge ring 26. As a result, ionization occurs in the heat transfer gas supplied to the back side of the substrate W and the back side of the edge ring 26. As a result, abnormal discharge may sometimes occur on the back side of the substrate W and / or the back side of the edge ring 26.

[0055] Therefore, in the mounting table 14 of the present embodiment, in order to suppress the discharge of the heat transfer gas, the bias electrode 21 is disposed in the first region 20a in the electrostatic chuck 20, and the bias electrode 25 is disposed in the second region 20b. Thus, the electrostatic capacitance between the bias electrode 21 and the substrate W and the electrostatic capacitance between the bias electrode 25 and the edge ring 26 can be increased.

[0056] The impedance Z of the high-frequency current flowing when the high-frequency LF is applied to the bias electrode 21 and the bias electrode 25 of the electrostatic chuck 20 is represented by the following equation.

[0057] Z=-(1 / Cω)×j

[0058] Thus, the impedance Z of the high-frequency current flowing through the electrostatic chuck 20 can be reduced by increasing the electrostatic capacitance C. Thus, the potential difference between the substrate W and the bias electrode 21 is reduced.

[0059] In addition, in the RC circuit, the time constant τ is expressed by the following equation.

[0060] τ=RC

[0061] Therefore, when RC is small, the potential is likely to change. Therefore, by increasing the electrostatic capacitance C and making RC larger, the change in the potential of the substrate W and the edge ring 26 can be suppressed.

[0062] For example, when the state of the bias electrode 21 instantly becomes -5000 V, the substrate W also instantly becomes -5000 V. At this time, the ions in the plasma are introduced into the substrate W, so the potential of the substrate W changes in the positive direction. By increasing the electrostatic capacitance between the substrate W and the bias electrode 21 and the electrostatic capacitance between the edge ring 26 and the bias electrode 25, it is possible to make it difficult for the potential of the substrate W to change in the positive direction.

[0063] According to the above description, in the mounting table 14 of the present embodiment, the bias electrode 21 and the bias electrode 25 are provided in the electrostatic chuck 20, and the electric power of the high frequency LF is applied to the bias electrode 21 and the bias electrode 25. As a result, the electrostatic capacity between the bias electrode 21 and the substrate W and the electrostatic capacity between the bias electrode 25 and the edge ring 26 can be increased compared with the case where the electric power of the high frequency LF is applied to the electrode plate 16. As a result, the potential difference between the substrate W and the edge ring 26 can be reduced, and the change in the potential of the substrate W and the edge ring 26 can be suppressed. As a result, the discharge of the heat transfer gas supplied to the back surface of the substrate W can be suppressed. As a result, the occurrence of abnormal discharge on the back surface of the substrate W and the back surface of the edge ring 26 can be suppressed.

[0064] In addition, it is preferable to set the thickness D1 from the first upper surface 201 to the bias electrode 21 and the thickness D2 from the second upper surface 202 to the bias electrode 25 to be equal. Thus, the electrostatic capacitance between the bias electrode 21 and the substrate W and the electrostatic capacitance between the bias electrode 25 and the edge ring 26 can be made substantially the same. Thus, the potential difference between the substrate W and the edge ring 26 can be made smaller or eliminated, and the occurrence of abnormal discharge between the substrate W and the edge ring 26 can be more effectively suppressed.

[0065] In addition, an adhesive layer for bonding the lower electrode 18 and the electrostatic chuck 20 is provided between the lower electrode 18 and the electrostatic chuck 20. When a high frequency LF is applied to the electrode plate 16 as in the prior art, the adhesive layer having a low dielectric constant prevents an increase in the electrostatic capacitance between the bias electrode 21 and the substrate W and the electrostatic capacitance between the bias electrode 25 and the edge ring 26.

[0066] In the mounting table 14 of the present embodiment, the bias electrode 21 and the bias electrode 25 are embedded on the adhesive layer between the lower electrode 18 and the electrostatic chuck 20. As a result, there is no adhesive layer between the bias electrode 21 and the substrate W and between the bias electrode 25 and the edge ring 26. Since there is no adhesive layer, the electrostatic capacitance between the bias electrode 21 and the substrate W and the electrostatic capacitance between the bias electrode 25 and the edge ring 26 can be made larger, and the heat transfer and stress relaxation of the adhesive layer can be freely designed.

[0067] In addition, although the electric power of the high frequency HF for plasma generation is applied to the electrode plate 16 , it may be applied to the upper electrode 30 .

[0068] [Each electrode]

[0069] Next, refer to Figure 3 , each electrode embedded in the electrostatic chuck 20 is described. Figure 3 (a) in the formula indicates Figure 2 FIG. 2 is a diagram of an AA cross section of the electrostatic chuck 20 shown. Figure 3 (b) is a diagram showing a BB cross section of the electrostatic chuck 20 . Figure 3 (c) is a diagram showing a CC cross section of the electrostatic chuck 20 .

[0070] Reference Figure 3 In the AA cross section of (a), a circular adsorption electrode 23 is provided in the circular first region 20a. The adsorption electrode 23 is a film-shaped or sheet-shaped electrode.

[0071] Reference Figure 3 In the BB cross section of (b) in FIG. 1 , annular adsorption electrodes 27a and 27b are provided in the second region 20b. The adsorption electrode 27a and the adsorption electrode 27b are respectively film-shaped or sheet-shaped electrodes. The adsorption electrode 27b is provided outside the adsorption electrode 27a.

[0072] Furthermore, a circular bias electrode 21 is provided inside the adsorption electrode 27a and in the first region 20a. The bias electrode 21 is in a sheet or mesh shape and is formed of conductive ceramics including ceramics and metals used in the electrostatic chuck 20.

[0073] The bias electrode 21 has a resistance value less than a predetermined value (eg, 0.1 Ω·cm). This is because if the resistance value of the sheet-like or mesh-like member forming the bias electrode 21 is greater than the predetermined value, the movement of charges in the radial direction takes time, and the high frequency LF cannot be stably applied.

[0074] For example, when the frequency of the high frequency LF is 400 kHz, for example, it is preferable to use a member having a very low resistance value and a charge transfer speed that is very fast with respect to the frequency as the bias electrode 21 .

[0075] The material used for the bias electrode 21 is not limited thereto, and may be conductive ceramics obtained by combining a high melting point metal material such as tungsten, tantalum, or molybdenum with ceramics constituting the electrostatic chuck.

[0076] Furthermore, considering the difference in linear expansion coefficient between the bias electrode 21 and the ceramic of the electrostatic chuck 20 in which the bias electrode 21 is embedded, the bias electrode 21 may be a mesh-shaped metal rather than a sheet-shaped one. Thus, the difference in contraction between the bias electrode 21 and the electrostatic chuck 20 caused by the difference in linear expansion coefficient between the bias electrode 21 and the electrostatic chuck 20 due to the heat input from the plasma can be mitigated, and the friction between the bias electrode 21 and the electrostatic chuck 20 can be reduced.

[0077] Reference Figure 3 In the CC section of (c) in FIG. 1 , a ring-shaped bias electrode 25 is provided in the second region 20b. The bias electrode 25 is a film-shaped or sheet-shaped electrode. The bias electrode 25 arranges the power supply terminals 25a uniformly in the circumferential direction. Thus, the impedance of the high frequency LF can be made uniform in the circumferential direction, and the deviation of the high frequency LF in the circumferential direction can be reduced.

[0078] The bias electrode 25 is in a sheet or mesh shape and is formed of conductive ceramics including ceramics and metals used in the electrostatic chuck 20 .

[0079] Bias electrode 25 has a resistance value of a predetermined value (eg, 0.1 Ω·cm) or less. The material used for bias electrode 25 is not limited thereto, and may be conductive ceramics obtained by combining high melting point metal materials such as tungsten, tantalum, and molybdenum with ceramics constituting the electrostatic chuck.

[0080] Furthermore, the bias electrode 25 may be a mesh-shaped metal instead of a sheet-shaped one. This can alleviate the difference in contraction between the bias electrode 25 and the electrostatic chuck 20 caused by the difference in linear expansion coefficient between the bias electrode 25 and the electrostatic chuck 20 due to the heat input from the plasma, thereby reducing the friction between the bias electrode 25 and the electrostatic chuck 20.

[0081] As described above, according to the mounting table 14 and the plasma processing apparatus 1 of this embodiment, by providing the bias electrodes 21 and 25 in the electrostatic chuck 20 , discharge of the heat transfer gas supplied between the lower surface of the substrate W and the upper surface of the electrostatic chuck 20 can be suppressed.

[0082] The mounting table and plasma processing device of one embodiment disclosed herein should be considered to be illustrative in all aspects and not restrictive. The above-mentioned embodiment can be deformed and improved in various ways without departing from the scope and the gist of the attached claims. The matters described in the above-mentioned multiple embodiments can also be set as other structures within the scope of non-contradiction, and can also be combined within the scope of non-contradiction.

[0083] The plasma processing device of the present invention can also be applied to any type of device including Atomic Layer Deposition (ALD) device, Capacitively Coupled Plasma (CCP) device, Inductively Coupled Plasma (ICP) device, Radial Line Slot Antenna (RLSA) device, Electron Cyclotron Resonance Plasma (ECR) device, and Helicon Wave Plasma (HWP) device.

[0084] Furthermore, the plasma processing apparatus may be an apparatus that performs a predetermined process (for example, an etching process, a film forming process, etc.) on a substrate.

Claims

1. A mounting table, characterized in that: include: an electrostatic chuck for supporting the substrate and edge ring; and a base supporting the electrostatic chuck, The electrostatic chuck has: A first region having a first upper surface capable of supporting a substrate placed on the first upper surface; a second region having a second upper surface and being arranged to be integrated with the periphery of the first region and capable of supporting an edge ring placed on the second upper surface; A first electrode disposed in the first region for applying a DC voltage; a second electrode disposed in the second region for applying a DC voltage; and A third electrode for applying bias electric power, The third electrode includes a 3-1 electrode provided in the first region and a 3-2 electrode provided in the second region. The bias power applied to the 3-1 electrode and the bias power applied to the 3-2 electrode can be controlled independently of each other.

2. The mounting table according to claim 1, wherein: The 3-1 electrode and the second electrode are arranged on the same surface of the electrostatic chuck.

3. The mounting table according to claim 1 or 2, characterized in that: The thickness from the first upper surface to the 3-1 electrode is equal to the thickness from the second upper surface to the 3-2 electrode.

4. The mounting table according to any one of claims 1 to 3, characterized in that: The electrostatic chuck is formed of a dielectric, The base is formed of metal.

5. The mounting table according to any one of claims 1 to 4, characterized in that: The third electrode is in a sheet or mesh shape having a sheet resistance equal to or less than a predetermined value.

6. The mounting table according to any one of claims 1 to 5, characterized in that: The third electrode is formed of conductive ceramics including ceramics and metals used in the electrostatic chuck.

7. A plasma processing device, characterized in that: include: a first high-frequency power source for applying high-frequency electric power for generating plasma; a second high-frequency power source and a third high-frequency power source for applying bias electric power for ion introduction; an electrostatic chuck for supporting the substrate and edge ring; and a base supporting the electrostatic chuck, The electrostatic chuck comprises: A first region having a first upper surface capable of supporting a substrate placed on the first upper surface; a second region having a second upper surface and being arranged to be integrated with the periphery of the first region and capable of supporting an edge ring placed on the second upper surface; A first electrode disposed in the first region for applying a DC voltage; a second electrode disposed in the second region for applying a DC voltage; and A third electrode for applying bias electric power, The third electrode includes a 3-1 electrode provided in the first region and a 3-2 electrode provided in the second region. The bias power applied to the 3-1 electrode and the bias power applied to the 3-2 electrode can be controlled independently of each other.

8. The plasma processing apparatus according to claim 7, wherein: The 3-1 electrode and the second electrode are arranged on the same surface of the electrostatic chuck.

9. The plasma processing device according to claim 7 or 8, characterized in that: The thickness from the first upper surface to the 3-1 electrode is equal to the thickness from the second upper surface to the 3-2 electrode.

10. The plasma processing apparatus according to any one of claims 7 to 9, characterized in that: The electrostatic chuck is formed of a dielectric, The base is formed of metal.

11. The plasma processing apparatus according to any one of claims 7 to 10, characterized in that: The third electrode is in a sheet or mesh shape having a sheet resistance equal to or less than a predetermined value.

12. The plasma processing apparatus according to any one of claims 7 to 11, characterized in that: The third electrode is formed of conductive ceramics including ceramics and metals used in the electrostatic chuck.

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