Plasma Processing Apparatus and Electrostatic Chuck

Abstract

To suppress the discharge of heat transfer gas supplied between the lower surface of a substrate and the upper surface of an electrostatic chuck.SOLUTION: A mounting table includes an electrostatic chuck for supporting a substrate and an edge ring, and a base that supports the electrostatic chuck, and the electrostatic chuck includes a first region having a first top surface and configured to support the substrate mounted on the first top surface, a second region having a second upper surface, integrally provided around the first region, and configured to support an edge ring mounted on the second upper surface, a first electrode provided in the first region and applying a DC voltage, a second electrode provided in the second region and applying a DC voltage, and a third electrode to which bias power is applied.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a mounting table and a plasma processing apparatus.

Background Art

[0002] In the manufacture of electronic devices, plasma processing apparatuses are used. The plasma processing apparatus excites a gas supplied into a chamber with high-frequency power applied to a mounting table, thereby generating plasma and subjecting a substrate on the mounting table to plasma processing.

[0003] In recent years, plasma processing has been performed using high-power conditions, particularly for high frequencies for ion drawing (biasing). In contrast, for example, Patent Document 1 proposes a technique for reducing the energy of ions irradiated onto the inner wall of a chamber body.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When plasma processing is performed using high-power conditions for high frequencies for ion drawing, the heat transfer gas supplied between the lower surface of the substrate and the upper surface of the electrostatic chuck may be ionized and a discharge may occur.

[0006] The present disclosure provides a mounting table and a plasma processing apparatus capable of suppressing discharge of the heat transfer gas supplied between the lower surface of the substrate and the upper surface of the electrostatic chuck.

Means for Solving the Problems

[0007] According to one aspect of the present disclosure, there is provided a mounting table including an electrostatic chuck for supporting a substrate and an edge ring, and a base for supporting the electrostatic chuck. The electrostatic chuck has a first upper surface and is configured to support a substrate placed thereon in a first region, and has a second upper surface and is configured to support an edge ring placed thereon in a second region that is integrally provided around the first region. The mounting table is provided with 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 a bias power.

Advantages of the Invention

[0008] According to one aspect, it is possible to suppress discharge of a heat transfer gas supplied between the lower surface of the substrate and the upper surface of the electrostatic chuck.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments for carrying out the present disclosure will be described with reference to the drawings. In each drawing, the same reference numerals are assigned to the same components, and redundant descriptions may be omitted.

[0011] [Plasma Processing Apparatus] FIG. 1 is a diagram schematically showing a plasma processing apparatus according to an embodiment. The plasma processing apparatus 1 shown in FIG. 1 is a capacitively coupled type apparatus. The plasma processing apparatus 1 has a chamber 10, and the chamber 10 provides an internal space 10s therein.

[0012] 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.

[0013] 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.

[0014] 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 within the internal space 10s. A member 15 is provided on the support portion 13. The member 15 may be formed of an insulator such as quartz. The member 15 can have a substantially cylindrical shape. Alternatively, the member 15 can be a plate-like body having an annular shape.

[0015] The plasma processing apparatus 1 further includes a substrate mounting table, that is, a mounting table 14 according to one exemplary embodiment. The mounting table 14 is supported by the support portion 13. The mounting table 14 is provided within the internal space 10s. The mounting table 14 is configured to support the substrate W within the chamber 10, that is, within the internal space 10s.

[0016] The mounting table 14 has a lower electrode 18 and an electrostatic chuck 20 according to one 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, for example, and has a substantially disk shape. The lower electrode 18 is provided on the electrode plate 16. The lower electrode 18 is formed of a conductor such as aluminum, for example, and has a substantially disk 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 for supporting the electrostatic chuck 20.

[0017] The electrostatic chuck 20 is provided 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 an edge ring 26 according to one exemplary embodiment.

[0018] The substrate W has, for example, a disk shape and is placed on the electrostatic chuck 20. The edge ring 26 is mounted on the electrostatic chuck 20 so as to surround the edge of the substrate W. The outer edge portion of the edge ring 26 may extend on the member 15. The edge ring 26 is a member having an annular shape. The edge ring 26 may be formed of, but is not limited to, silicon, silicon carbide, or quartz. The edge ring 26 is also called a focus ring.

[0019] A flow path 18f is provided inside the lower electrode 18. A heat exchange medium (for example, a refrigerant) is supplied to the flow path 18f from a chiller unit 22 provided outside the chamber 10 via a pipe 22a. The heat exchange medium supplied to the flow path 18f is returned to the chiller unit 22 via a pipe 22b. In the plasma processing apparatus 1, the temperature of the substrate W placed on the electrostatic chuck 20 is adjusted by heat exchange between the heat exchange medium and the lower electrode 18.

[0020] The plasma processing apparatus 1 is provided with a gas supply line 24. The gas supply line 24 supplies a heat transfer gas (e.g., He gas) from the heat transfer gas supply mechanism between the upper surface of the electrostatic chuck 20 and the lower surface of the substrate W.

[0021] The plasma processing apparatus 1 further includes an upper electrode 30. The upper electrode 30 is provided above the mounting table 14. The upper electrode 30 is supported by the upper part of the chamber body 12 via 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.

[0022] The upper electrode 30 may include a top plate 34 and a support 36. The lower surface of the top plate 34 is the lower surface on the side of the internal space 10s and defines 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 discharge holes 34a are formed in the top plate 34. The plurality of gas discharge holes 34a penetrate the top plate 34 in its plate thickness direction.

[0023] The support 36 detachably supports the top plate 34. The support 36 is formed of a conductive material such as aluminum. A gas diffusion chamber 36a is provided inside the support 36. A plurality of gas holes 36b are formed in the support 36. The plurality of gas holes 36b extend downward from the gas diffusion chamber 36a. The plurality of gas holes 36b communicate with the plurality of gas discharge holes 34a respectively. A gas inlet 36c is formed in the support 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.

[0024] A gas supply unit GS is connected to a gas supply pipe 38. The gas supply unit GS includes a gas source group 40, a valve group 41, a flow rate 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 rate controller group 42, and the valve group 43. The gas source group 40 includes a plurality of gas sources. Each of the valve group 41 and the valve group 43 includes a plurality of on-off valves. The flow rate controller group 42 includes a plurality of flow rate controllers. Each of the plurality of flow rate controllers in the flow rate controller group 42 is a mass flow controller or a pressure control type flow rate controller. Each of the plurality of gas sources in the gas source group 40 is connected to the gas supply pipe 38 via a corresponding on-off valve in the valve group 41, a corresponding flow rate controller in the flow rate controller group 42, and a corresponding on-off valve in the valve group 43.

[0025] In the plasma processing apparatus 1, a shield 46 is detachably provided along the inner wall surface of the chamber body 12. The shield 46 is also provided on the outer periphery of the support portion 13. The shield 46 prevents reaction products such as etching by-products from adhering to the chamber body 12. The shield 46 is configured, 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.

[0026] A baffle plate 48 is provided between the support portion 13 and the side wall of the chamber body 12. The baffle plate 48 is configured, 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. A plurality of through holes are formed in the baffle plate 48. An exhaust port 12e is provided below the baffle plate 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 has a vacuum pump such as a pressure regulating valve and a turbo molecular pump.

[0027] The plasma processing apparatus 1 includes a first high-frequency power supply 61 that applies high-frequency HF power for plasma generation. The first high-frequency power supply 61 is configured to generate high-frequency HF power in order to generate plasma from a gas within the chamber 10. The frequency of the high-frequency HF is, for example, a frequency within the range of 27 MHz to 100 MHz.

[0028] The first high-frequency power supply 61 is electrically connected to the lower electrode 18 via a matcher 63. The matcher 63 has a matching circuit. The matching circuit of the matcher 63 is configured to match the impedance on the load side (lower electrode side) of the first high-frequency power supply 61 to the output impedance of the first high-frequency power supply 61. In another embodiment, the first high-frequency power supply 61 may be electrically connected to the upper electrode 30 via the matcher 63.

[0029] The plasma processing apparatus 1 may further include a second high-frequency power supply 62 that applies high-frequency LF power for ion drawing-in. The second high-frequency power supply 62 is configured to generate high-frequency LF power. The high-frequency LF has a frequency suitable mainly for drawing ions into the substrate W and is, for example, a frequency within the range of 400 kHz to 13.56 MHz. Alternatively, the high-frequency LF may be a pulsed voltage having a rectangular waveform.

[0030] The second high-frequency power supply 62 is electrically connected to the bias electrode 21 within the electrostatic chuck 20 via a matcher 64. The matcher 64 has a matching circuit. The matching circuit of the matcher 64 is configured to match the impedance on the load side (bias electrode side) of the second high-frequency power supply 62 to the output impedance of the second high-frequency power supply 62.

[0031] The plasma processing apparatus 1 may further include a control unit 80. The control unit 80 can be a computer including a processor, a storage unit such as a memory, an input device, a display device, a signal input / output interface, etc. The control unit 80 controls each part of the plasma processing apparatus 1. In the control unit 80, an operator can perform input operations of commands and the like for managing the plasma processing apparatus 1 using the input device. Also, in the control unit 80, the operating status of the plasma processing apparatus 1 can be visualized and displayed by the display device. Further, a control program and recipe data are stored in the storage unit of the control unit 80. The control program is executed by the processor of the control unit 80 to execute various processes in the plasma processing apparatus 1. By the processor of the control unit 80 executing the control program and controlling each part of the plasma processing apparatus 1 according to the recipe data, various processes, for example, a plasma processing method, are executed in the plasma processing apparatus 1.

[0032] [Mounting table] Hereinafter, the mounting table 14 according to an embodiment will be described in detail. In the following description, reference is made to FIG. 2 together with FIG. 1. FIG. 2 is a cross-sectional view showing the mounting table 14 according to an embodiment.

[0033] 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.

[0034] 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 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.

[0035] The second region 20b is a region having an annular shape. The second region 20b shares a central axis (axis AX in FIG. 2) with the first region 20a. The second region 20b has a second upper surface 202. The second region 20b is integrally provided around the first region 20a and is configured to support an edge ring 26 mounted on the second upper surface 202 (see FIG. 1).

[0036] The main body of the electrostatic chuck 20, that is, the first region 20a and the second region 20b, may be formed from a single dielectric material. That is, the dielectric material constituting the first region 20a and the dielectric material constituting the second region 20b may be the same. For example, the main body of the electrostatic chuck 20 may be formed from ceramics such as aluminum oxide and aluminum nitride. In this 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.

[0037] The electrostatic chuck 20 further has a suction electrode 23. The suction electrode 23 is provided in the first region 20a. The suction electrode 23 is connected to a DC power supply 20p via a switch 20s. When a DC voltage from the DC power supply 20p is applied to the suction electrode 23, an electrostatic attraction force is generated between the first region 20a and the substrate W. Due to the generated electrostatic attraction force, the substrate W is attracted to the first region 20a and held by the first region 20a. The suction electrode 23 is provided in the first region 20a and is an example of a first electrode to which a DC voltage is applied.

[0038] The electrostatic chuck 20 further has a suction electrode 27a and a suction electrode 27b (hereinafter also collectively referred to as the suction electrode 27). The suction electrodes 27a and 27b are provided in the second region 20b. The suction electrodes 27a and 27b extend in the circumferential direction with respect to the central axis of the electrostatic chuck 20. The suction electrode 27b is provided outside the suction electrode 27a. A DC power supply 20m is electrically connected to the suction electrode 27a via a switch 20n, and a DC power supply 20r is electrically connected to the suction electrode 27b via a switch 20t. A DC voltage is applied from the DC power supplies 20m and 20r to each of the suction electrodes 27a and 27b so that a potential difference is generated between the suction electrode 27a and the suction electrode 27b. For example, the polarity of the DC voltage applied from the DC power supply 20m to the suction electrode 27a may be opposite to the polarity of the DC voltage applied from the DC power supply 20r to the suction electrode 27b. However, the suction electrode 27 is not limited to a bipolar electrode and may be a unipolar electrode. When DC voltages are applied from the DC power supplies 20m and 20r to the suction electrodes 27a and 27b, an electrostatic attraction force is generated between the second region 20b and the edge ring 26. Due to the generated electrostatic attraction force, the edge ring 26 is attracted to the second region 20b and held by the second region 20b. The suction electrodes 27a and 27b are provided in the second region 20b and are an example of a second electrode to which a DC voltage is applied.

[0039] The bias electrode 21 is provided below the suction electrode 23 in the first region 20a. The bias electrode 25 is provided below the suction electrodes 27a and 27b in the second region 20b. A third high-frequency power supply 65 is electrically connected to the bias electrode 25 in the second region 20b via a matcher 66. The matcher 66 has a matching circuit. The matching circuit of the matcher 66 is configured to match the impedance on the load side (bias electrode side) of the third high-frequency power supply 65 with the output impedance of the third high-frequency power supply 65.

[0040] The bias electrodes 21 and 25 apply a bias power for ion drawing-in. The bias power is applied by a DC voltage or a high-frequency voltage. In the examples of FIGS. 1 and 2, the bias electrode 25 applies the bias power by a high-frequency voltage from the third high-frequency power source 65, but it is not limited thereto, and the bias power may be applied by a DC voltage from a DC power source. When the bias power is applied to the bias electrode 21, the ions in the plasma are drawn toward the first region 20a. Thereby, process characteristics such as, for example, an etching rate and a film formation rate over 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 drawn toward the second region 20b. Thereby, the process characteristics of the edge region of the substrate W can be controlled.

[0041] The bias electrodes 21 and 25 are an example of a third electrode that applies a bias power. The bias electrode 21 is an example of a third-1 electrode provided in the first region 20a, and the bias electrode 25 is an example of a third-2 electrode provided in the second region 20b. The bias powers applied to the bias electrode 21 and the bias electrode 25 are independently controlled by the second high-frequency power source 62 and the third high-frequency power source 65, respectively. The third electrode has at least the bias electrode 21 and may not have the bias electrode 25.

[0042] 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 a substantially identical circular shape in diameter. The adsorption electrodes 27a and 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 25 have an annular shape. The radial widths of the adsorption electrode 27a and the adsorption electrode 27b have substantially the same length, and the radial width of the bias electrode 25 is larger than the total radial width of the adsorption electrode 27a and the adsorption electrode 27b.

[0043] The bias electrode 21, the adsorption electrode 27a, and the adsorption electrode 27b are arranged in 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.

[0044] [Reasons for Providing the Bias Electrode Inside the Electrostatic Chuck] The reasons for providing the bias electrode 21 and the bias electrode 25 inside the electrostatic chuck 20 will be described. In recent years, plasma processing has been performed using high-power conditions, particularly for high-frequency LF for ion drawing. When high-power high-frequency LF is applied to the electrode plate 16, a potential difference occurs between the electrode plate 16 and the substrate W and between the electrode plate 16 and the edge ring 26 according to the capacitance between the electrode plate 16 and the substrate W and the capacitance between the electrode plate 16 and the edge ring 26. As a result, ionization may occur in the heat transfer gas supplied to the back surface of the substrate W and the back surface of the edge ring 26. As a result, abnormal discharge may occur on the back surface of the substrate W and / or the back surface of the edge ring 26.

[0045] Therefore, in the mounting table 14 according to the present embodiment, in order to suppress the discharge of the heat transfer gas, the bias electrode 21 is provided in the first region 20a inside the electrostatic chuck 20, and the bias electrode 25 is provided in the second region 20b. Thereby, the capacitance between the bias electrode 21 and the substrate W and the capacitance between the bias electrode 25 and the edge ring 26 can be increased.

[0046] The impedance Z of the high-frequency current flowing when 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 formula. Z = -(1 / Cω)×j Therefore, by increasing the capacitance C, the impedance Z of the high-frequency current flowing through the electrostatic chuck 20 can be decreased. Thereby, the potential difference between the substrate W and the bias electrode 21 is decreased.

[0047] Also, in the RC circuit, the time constant τ is represented by the following formula. τ = RC Therefore, when RC is small, the potential is likely to change. For this reason, by increasing the capacitance C, RC can be increased to suppress the potential fluctuations in the substrate W and the edge ring 26.

[0048] For example, when the state of the bias electrode 21 instantaneously becomes -5000V, the substrate W also instantaneously becomes -5000V. At this time, since ions in the plasma are drawn into the substrate W, the potential of the substrate W fluctuates in the positive direction. By increasing the capacitance between the substrate W and the bias electrode 21 and the 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 fluctuate in the positive direction.

[0049] From the above, in the mounting table 14 according to the present embodiment, the bias electrode 21 and the bias electrode 25 are provided in the electrostatic chuck 20, and high-frequency LF power is applied to the bias electrode 21 and the bias electrode 25. According to this, the capacitance between the bias electrode 21 and the substrate W and the capacitance between the bias electrode 25 and the edge ring 26 can be made larger than when high-frequency LF power is applied to the electrode plate 16. Thereby, the potential difference between the substrate W and the edge ring 26 can be made smaller, and the potential fluctuations of the substrate W and the edge ring 26 can be suppressed. Thereby, the discharge of the heat transfer gas supplied to the back surface of the substrate W can be suppressed. As a result, it is possible to suppress the occurrence of abnormal discharge on the back surface of the substrate W and the back surface of the edge ring 26.

[0050] Further, it is preferable to arrange 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. Thereby, the capacitances between the bias electrode 21 and the substrate W and between the bias electrode 25 and the edge ring 26 can be made substantially the same. Thereby, 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.

[0051] Note that an adhesive layer for adhering the lower electrode 18 and the electrostatic chuck 20 is provided between the lower electrode 18 and the electrostatic chuck 20. When high-frequency LF is applied to the electrode plate 16 as before, the adhesive layer with a low dielectric constant hinders the increase in the capacitance between the bias electrode 21 and the substrate W and the capacitance between the bias electrode 25 and the edge ring 26.

[0052] On the other hand, in the mounting table 14 according to 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. Therefore, no adhesive layer is interposed between the bias electrode 21 and the substrate W and between the bias electrode 25 and the edge ring 26. According to this, the capacitance between the bias electrode 21 and the substrate W and the capacitance between the bias electrode 25 and the edge ring 26 can be made larger due to the absence of the adhesive layer, and a free design regarding heat transfer and stress relaxation of the adhesive layer becomes possible.

[0053] Note that the power of high-frequency HF for plasma generation is applied to the electrode plate 16, but it may also be applied to the upper electrode 30.

[0054] [Each electrode] Next, each electrode embedded in the electrostatic chuck 20 will be described with reference to FIG. 3. FIG. 3(a) is a diagram showing an A-A cross section of the electrostatic chuck 20 shown in FIG. 2. FIG. 3(b) is a diagram showing a B-B cross section of the electrostatic chuck 20. FIG. 3(c) is a diagram showing a C-C cross section of the electrostatic chuck 20.

[0055] Referring to the A-A cross section of FIG. 3(a), a circular adsorption electrode 23 is provided in a circular first region 20a. The adsorption electrode 23 is a film-like or sheet-like electrode.

[0056] Referring to the B-B cross section of FIG. 3(b), annular adsorption electrodes 27a and 27b are provided in the second region 20b. Each of the adsorption electrode 27a and the adsorption electrode 27b is a film-like or sheet-like electrode. The adsorption electrode 27b is provided outside the adsorption electrode 27a.

[0057] Also, a circular bias electrode 21 is provided inside the adsorption electrode 27a and within the first region 20a. The bias electrode 21 is in the form of a sheet or a mesh. The bias electrode 21 is formed of a conductive ceramic containing the ceramics and metal used for the electrostatic chuck 20.

[0058] The bias electrode 21 has a resistance value of a predetermined value (for example, 0.1 Ω·cm) or less. 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, it takes time for the charge to move in the radial direction, and the high-frequency LF cannot be stably applied.

[0059] For example, when the frequency of the high-frequency LF is, for example, 400 kHz, it is preferable to use a member with a sufficiently low resistance value that has a charge movement speed sufficiently fast for that frequency as the bias electrode 21.

[0060] The material used for the bias electrode 21 is not limited to this, but may be a conductive ceramic that combines a high melting point metal-based material such as tungsten, tantalum, or molybdenum with the ceramics constituting the electrostatic chuck.

[0061] Furthermore, considering the difference in the linear expansion coefficient between the members between the bias electrode 21 and the ceramics 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. Thereby, the difference in shrinkage between the bias electrode 21 and the electrostatic chuck 20 caused by the difference in the linear expansion coefficient between the bias electrode 21 and the electrostatic chuck 20 due to the heat input from the plasma can be alleviated, and the friction between the bias electrode 21 and the electrostatic chuck 20 can be reduced.

[0062] Referring to the C-C cross-section of FIG. 3(c), an annular bias electrode 25 is provided in the second region 20b. The bias electrode 25 is a film-like or sheet-like electrode. The bias electrode 25 arranges power supply terminals 25a evenly in the circumferential direction. Thereby, the impedance of the high-frequency LF can be made uniform in the circumferential direction, and the bias in the circumferential direction of the high-frequency LF can be reduced.

[0063] The bias electrode 25 is sheet-like or mesh-like. The bias electrode 25 is formed of a conductive ceramic containing ceramics and metal used for the electrostatic chuck 20.

[0064] The bias electrode 25 has a resistance value of a predetermined value (for example, 0.1 Ω·cm) or less. The material used for the bias electrode 25 is not limited to this, but may be a conductive ceramic combining a high melting point metal material such as tungsten, tantalum, molybdenum, etc. and the ceramics constituting the electrostatic chuck.

[0065] Furthermore, the bias electrode 25 may be a mesh-like metal rather than a sheet-like one. Thereby, the difference in shrinkage between the bias electrode 25 and the electrostatic chuck 20 caused by the difference in the linear expansion coefficient between the bias electrode 25 and the electrostatic chuck 20 due to the heat input from the plasma can be alleviated, and the friction between the bias electrode 25 and the electrostatic chuck 20 can be reduced.

[0066] As described above, according to the mounting table 14 and the plasma processing apparatus 1 of the present embodiment, by providing the bias electrodes 21 and 25 inside the electrostatic chuck 20, the 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.

[0067] The embodiments disclosed above include, for example, the following aspects. (Appendix 1) An electrostatic chuck for supporting a substrate and an edge ring, A base for supporting the electrostatic chuck, and The electrostatic chuck, A first region having a first upper surface and configured to support a substrate placed on the first upper surface, A second region having a second upper surface, integrally provided around the first region, and configured to support 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, A third electrode for applying bias power, A mounting table having the above. (Appendix 2) The third electrode has a third - 1 electrode provided in the first region and a third - 2 electrode provided in the second region, The bias power applied to the third - 1 electrode and the bias power applied to the third - 2 electrode are independently controlled, The mounting table according to Appendix 1. (Appendix 3) The third - 1 electrode and the second electrode are arranged in the same plane of the electrostatic chuck, The mounting table according to Appendix 2. (Appendix 4) The thickness from the first upper surface to the third - 1 electrode is equal to the thickness from the second upper surface to the third - 2 electrode, The mounting table according to Appendix 2 or 3. (Appendix 5) The electrostatic chuck is formed of a dielectric, The base is formed of a metal, The mounting table according to any one of Appendices 1 to 4. (Appendix 6) The third electrode is in a sheet or mesh shape having a sheet resistance of a predetermined value or less, The mounting table according to any one of Appendices 1 to 5. (Appendix 7) The third electrode is formed of a conductive ceramic containing the ceramics and metal used for the electrostatic chuck, The mounting table according to any one of Appendices 1 to 6. (Appendix 8) A first high-frequency power supply for applying high-frequency power for plasma generation, a second high-frequency power supply and a third high-frequency power supply for applying bias power for ion drawing-in, an electrostatic chuck for supporting a substrate and an edge ring, a base for supporting the electrostatic chuck, and the electrostatic chuck has a first upper surface and is configured to support a substrate placed on the first upper surface; a first region, has a second upper surface and is integrally provided around the first region and is configured to support an edge ring placed on the second upper surface; a second region, 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, a third electrode for applying bias power, and a plasma processing apparatus having the same.

[0068] The mounting table and the plasma processing apparatus according to the embodiment disclosed this time should be considered as illustrative in all respects and not restrictive. The above embodiment can be modified and improved in various forms without departing from the scope and gist of the appended claims. Matters described in the above plurality of embodiments can adopt other configurations and can be combined within a non-contradictory range.

[0069] The plasma processing apparatus of the present disclosure is applicable to any type of apparatus such as an Atomic Layer Deposition (ALD) apparatus, a Capacitively Coupled Plasma (CCP), an Inductively Coupled Plasma (ICP), a Radial Line Slot Antenna (RLSA), an Electron Cyclotron Resonance Plasma (ECR), and a Helicon Wave Plasma (HWP).

[0070] Further, the plasma processing apparatus may be any apparatus that performs a predetermined process (e.g., etching process, film forming process, etc.) on a substrate.

Explanation of Signs

[0071] 1... Plasma processing apparatus, 10... Chamber, 14... Mounting table, 16... Electrode plate, 18... Lower electrode, 20... Electrostatic chuck, 20a... First region, 20b... Second region, 21, 25... Bias electrodes, 26... Edge ring, 23, 27a, 27b... Adsorption electrodes, 61... First high-frequency power source, 62... Second high-frequency power source, 65... Third high-frequency power source, 201... First upper surface, 202... Second upper surface, W... Substrate

Claims

1. a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support including a substrate rest and an edge ring rest surrounding the substrate rest; a first chucking electrode disposed on the substrate placement portion; a first bias electrode disposed below the first chucking electrode on the substrate mounting portion; a second bias electrode disposed on the edge ring mounting portion; a first power supply electrically connected to the first bias electrode; a second power supply electrically connected to the second bias electrode. Plasma processing equipment.

2. The substrate mounting portion and the edge ring mounting portion are integrated. The plasma processing apparatus according to claim 1 .

3. The distance between the upper surface of the edge ring mounting portion and the second bias electrode is equal to the distance between the upper surface of the substrate mounting portion and the first bias electrode.

3. The plasma processing apparatus according to claim 1 or 2.

4. An upper surface of the edge ring mounting portion is formed at a position lower than an upper surface of the substrate mounting portion.

4. The plasma processing apparatus according to claim 1, wherein the first and second electrodes are disposed on the first and second surfaces of the substrate.

5. The edge ring mounting portion further includes a second suction electrode disposed between an upper surface of the edge ring mounting portion and the second bias electrode.

5. The plasma processing apparatus according to claim 1, wherein the first and second electrodes are disposed on the first and second surfaces of the substrate.

6. The second bias electrode is disposed at a lower position than the first bias electrode. The plasma processing apparatus according to any one of claims 1 to 5.

7. The first bias electrode and the second attraction electrode are arranged at the same height. The plasma processing apparatus according to claim 5 .

8. A substrate placement section for placing a substrate; an edge ring placement portion for placing an edge ring surrounding the substrate; a first chucking electrode disposed on the substrate placement portion; a first bias electrode disposed below the first chucking electrode on the substrate mounting portion; a second bias electrode disposed on the edge ring mounting portion; Electrostatic chuck.

9. The distance between the upper surface of the edge ring mounting portion and the second bias electrode is equal to the distance between the upper surface of the substrate mounting portion and the first bias electrode.

9. The electrostatic chuck of claim 8.

10. An upper surface of the edge ring mounting portion is formed at a position lower than an upper surface of the substrate mounting portion.

10. The electrostatic chuck according to claim 8 or 9.

11. The edge ring mounting portion further includes a second chucking electrode disposed between an upper surface of the edge ring mounting portion and the second bias electrode. The electrostatic chuck according to any one of claims 8 to 10.

12. The second bias electrode is disposed at a lower position than the first bias electrode.

12. The electrostatic chuck according to claim 8.

13. The first bias electrode and the second attraction electrode are disposed at the same height.

12. The electrostatic chuck of claim 11.

14. a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support including a substrate rest and an edge ring rest surrounding the substrate rest; a first bias electrode disposed within the substrate placement portion; a second bias electrode disposed within the edge ring mounting portion; a first voltage generating unit electrically connected to the first bias electrode and configured to generate a pulsed voltage; a second voltage generating unit electrically connected to the second bias electrode and configured to generate a bias by a DC voltage; Plasma processing equipment.

15. The substrate mounting portion and the edge ring mounting portion are integrated. The plasma processing apparatus according to claim 14.

16. A distance between an upper surface of the edge ring mounting portion and the second bias electrode is equal to a distance between an upper surface of the substrate mounting portion and the first bias electrode. The plasma processing apparatus according to claim 14 or 15.

17. An upper surface of the edge ring mounting portion is formed at a position lower than an upper surface of the substrate mounting portion. The plasma processing apparatus according to any one of claims 14 to 16.

18. The substrate mounting portion further includes a first chucking electrode disposed between an upper surface of the substrate mounting portion and the first bias electrode. The plasma processing apparatus according to any one of claims 14 to 17.

19. The edge ring mounting portion further includes a second chucking electrode disposed between an upper surface of the edge ring mounting portion and the second bias electrode. The plasma processing apparatus according to claim 18.

20. The second bias electrode is disposed at a lower position than the first bias electrode.

20. The plasma processing apparatus according to claim 14,

21. The first bias electrode and the second attraction electrode are disposed at the same height. The plasma processing apparatus according to claim 19 .

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