Plasma processing apparatus and mounting table

Abstract

To suppress the discharge of heat transfer gas supplied between the bottom surface of a substrate and the top surface of an electrostatic chuck.SOLUTION: A mounting table includes an electrostatic chuck that supports 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 resting on the first top surface, a second region having a second top surface, integrally provided around the first region and configured to support the edge ring resting on the second top 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 technology]

[0002] In the manufacture of electronic devices, a plasma processing apparatus is used, which excites a gas supplied into a chamber by applying high-frequency power to a mounting table to generate plasma and perform plasma processing on a substrate placed on the mounting table.

[0003] In recent years, plasma processing has been performed using high power conditions, particularly for high frequency waves for ion attraction (biasing). In response to this, for example, Patent Document 1 proposes a technique for reducing the energy of ions irradiated onto the inner wall of the chamber body. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-36658 A Summary of the Invention [Problem to be solved by the invention]

[0005] When plasma processing is performed using high power conditions for the high frequency waves for attracting ions, the heat transfer gas supplied between the lower surface of the substrate and the upper surface of the electrostatic chuck may be ionized, causing discharge.

[0006] The present disclosure provides 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. [Means for solving the problem]

[0007] According to one aspect of the present disclosure, there is provided a plasma processing chamber; and a gas supply device disposed within the plasma processing chamber,A first upper surface on which a substrate is placed. Substrate placement section and The above-mentioned disposed on the first upper surface Place an edge ring around the board Has a second upper surface The present invention relates to a substrate mounting system, and a substrate mounting method thereof. The present invention relates to a substrate mounting system including an edge ring mounting portion, a first bias electrode disposed in the substrate mounting portion, a second bias electrode disposed in the edge ring mounting portion, a first bias power supply electrically connected to the first bias electrode, and a second bias power supply electrically connected to the second bias electrode. The second the top surface and the second bias electrode Top of The distance between the substrate placement part The first the top surface and the first bias electrode Top of A plasma processing apparatus is provided, in which the distance between the Effect of the Invention

[0008] According to one aspect, discharge of a heat transfer gas supplied between a lower surface of a substrate and an upper surface of an electrostatic chuck can be suppressed. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic cross-sectional view showing an example of a plasma processing apparatus according to an embodiment; [Diagram 2] FIG. 2 is a diagram illustrating an example of a mounting table according to an embodiment. [Diagram 3] 2A to 2C are views showing cross sections AA, BB, and CC of a mounting table according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and duplicated descriptions may be omitted.

[0011] [Plasma processing equipment] FIG. 1 is a schematic diagram of a plasma processing apparatus according to an embodiment. The plasma processing apparatus 1 shown in FIG. 1 is a capacitively coupled apparatus. The plasma processing apparatus 1 includes a chamber 10. (Plasma Processing Chamber)The chamber 10 defines an interior space 10s therein.

[0012] 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 made of, for example, aluminum. A corrosion-resistant film is provided on the inner wall surface of the chamber body 12. The corrosion-resistant film may be a film made of a ceramic such as aluminum oxide or yttrium oxide.

[0013] A passage 12p is formed in a sidewall of the chamber body 12. The substrate W passes through the passage 12p when being transferred between the internal space 10s and the outside of the chamber 10. The passage 12p can be opened and closed by a gate valve 12g. The gate valve 12g is provided along the sidewall of the chamber body 12.

[0014] A support 13 is provided on the bottom of the chamber body 12. The support 13 is made of an insulating material. The support 13 has a substantially cylindrical shape. The support 13 extends upward from the bottom of the chamber body 12 in the internal space 10s. A member 15 is provided on the support 13. The member 15 may be made of an insulating material such as quartz. The member 15 may have a substantially cylindrical shape. Alternatively, the member 15 may be a plate-like body having a ring shape.

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

[0016] The mounting table 14 includes a lower electrode 18 and an electrostatic chuck 20 according to an exemplary embodiment. The mounting table 14 may further include an electrode plate 16. The electrode plate 16 is made of a conductor such as aluminum and has a substantially disk-like shape. The lower electrode 18 is provided on the electrode plate 16. The lower electrode 18 is made of a conductor such as aluminum and has a substantially disk-like 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 a support 13. The electrode plate 16 and the lower electrode 18 are an example of a base that supports the electrostatic chuck 20.

[0017] The electrostatic chuck 20 is disposed on the lower electrode 18. The edge of the electrostatic chuck 20 and an edge ring 26 are surrounded by member 15. The electrostatic chuck 20 supports a substrate W and the 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. An outer peripheral 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 made 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 (e.g., 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 (for example, He gas) from a heat transfer gas supply mechanism to 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 on the upper part of the chamber body 12 via a member 32. The member 32 is made 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 bottom surface of the top plate 34 is the bottom 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 that generates 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 the plate thickness direction.

[0023] The support 36 detachably supports the top plate 34. The support 36 is made of a conductive material such as aluminum. A gas diffusion chamber 36a is provided inside the support 36. A plurality of gas holes 36b 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 are connected to 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 the 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 opening and closing valves. The flow rate controller group 42 includes a plurality of flow rate controllers. Each of the plurality of flow rate controllers of 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 of the gas source group 40 is connected to the gas supply pipe 38 via a corresponding opening and closing valve of the valve group 41, a corresponding flow rate controller of the flow rate controller group 42, and a corresponding opening and closing valve of 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 part 13. The shield 46 prevents reaction products such as etching by-products from adhering to the chamber body 12. The shield 46 is formed, for example, by forming a corrosion-resistant film on the surface of a member made of aluminum. The corrosion-resistant film can be a film made of ceramics such as yttrium oxide.

[0026] A baffle plate 48 is provided between the support 13 and the side wall of the chamber body 12. The baffle plate 48 is formed by forming a corrosion-resistant film on the surface of a member made of, for example, aluminum. The corrosion-resistant film may be a film made 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 pressure adjustment valve and a vacuum pump such as 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 generating plasma. The first high frequency power supply 61 is configured to generate high frequency HF power in order to generate plasma from a gas in the chamber 10. The frequency of the high frequency HF is, for example, within a 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 matching box 63. The matching box 63 has a matching circuit. The matching circuit of the matching box 63 is configured to match the impedance of 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 matching box 63.

[0029] The plasma processing apparatus 1 may further include a second high frequency power supply 62 that applies high frequency LF power for attracting ions. The second high frequency power supply 62 is configured to generate high frequency LF power. The high frequency LF has a frequency suitable for attracting ions mainly to the substrate W, and is, for example, a frequency within a 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 in the electrostatic chuck 20 via a matching box 64. The matching box 64 has a matching circuit. The matching circuit of the matching box 64 is configured to match the impedance of 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 may be a computer including a processor, a storage unit such as a memory, an input device, a display device, a signal input / output interface, and the like. The control unit 80 controls each unit of the plasma processing apparatus 1. In the control unit 80, an operator can use the input device to input commands and the like to manage the plasma processing apparatus 1. In addition, the control unit 80 can visualize and display the operating status of the plasma processing apparatus 1 using the display device. Furthermore, 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. The processor of the control unit 80 executes the control program and controls each unit of the plasma processing apparatus 1 according to the recipe data, whereby various processes, for example, a plasma processing method, are executed in the plasma processing apparatus 1.

[0032] [Placement table] The mounting table 14 according to one embodiment will be described in detail below. In the following description, Fig. 2 will be referred to in addition to Fig. 1. Fig. 2 is a cross-sectional view showing the mounting table 14 according to one 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 from 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 a 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 an annular region. 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, i.e., 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 a ceramic such as aluminum oxide or 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 includes an adsorption electrode 23. The adsorption electrode 23 is provided in the first region 20a. The adsorption 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 adsorption electrode 23, an electrostatic attraction force is generated between the first region 20a and the substrate W. The generated electrostatic attraction force attracts the substrate W to the first region 20a and the substrate W 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.

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

[0039] The bias electrode 21 is provided below the chucking electrode 23 in the first region 20a. The bias electrode 25 is provided below the chucking electrodes 27a and 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 a 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 (bias electrode side) of the third high frequency power supply 65 to the output impedance of the third high frequency power supply 65.

[0040] The bias electrode 21 and the bias electrode 25 apply bias power for attracting ions. The bias power is applied by a DC voltage or a high-frequency voltage. In the example of FIG. 1 and FIG. 2, the bias electrode 25 applies bias power by a high-frequency voltage from the third high-frequency power supply 65, but this is not limited thereto, and bias power may be applied by a DC voltage from a DC power supply. When bias power is applied to the bias electrode 21, ions in the plasma are attracted toward the first region 20a. This makes it possible to control process characteristics, such as an etching rate and a film formation rate, over the entire surface of the substrate W. When bias power is applied to the bias electrode 25, ions in the plasma are attracted toward the second region 20b. This makes it possible to control process characteristics of the edge region of the substrate W.

[0041] The bias electrode 21 and the bias electrode 25 are an example of a third electrode that applies bias power, the bias electrode 21 is an example of a 3-1 electrode provided in the first region 20a, and the bias electrode 25 is an example of a 3-2 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 supply 62 and the third high frequency power supply 65. The third electrode may have at least the bias electrode 21, but may not have the bias electrode 25.

[0042] The chucking electrode 23 in the first region 20a is provided between the first upper surface 201 and the bias electrode 21. The chucking electrode 23 and the bias electrode 21 have a circular shape with approximately the same diameter. The chucking electrode 27a and the chucking electrode 27b in the second region 20b are provided between the second upper surface 202 and the bias electrode 25. The chucking electrode 27a, the chucking electrode 27b, and the bias electrode 25 have an annular shape. The radial widths of the chucking electrode 27a and the chucking electrode 27b have approximately the same length, and the radial width of the bias electrode 25 is larger than the total radial width of the chucking electrode 27a and the chucking electrode 27b.

[0043] The bias electrode 21, and the attraction electrodes 27a and 27b are disposed on the same plane of the electrostatic chuck 20. A thickness D1 from the first upper surface 201 to the upper surface of the bias electrode 21 and a thickness D2 from the second upper surface 202 to the upper surface of the bias electrode 25 are equal to each other.

[0044] [Reason for providing a bias electrode inside the electrostatic chuck] The reason for providing the bias electrode 21 and the bias electrode 25 in the electrostatic chuck 20 will be described. In recent years, plasma processing has been performed using high power conditions, particularly for the high frequency LF for attracting ions. When a 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 depending on 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. This causes ionization of the heat transfer gas supplied to the rear surface of the substrate W and the rear surface of the edge ring 26. As a result, abnormal discharge may occur on the rear surface of the substrate W and / or the rear surface of the edge ring 26.

[0045] Therefore, in the mounting table 14 according to the present embodiment, in order to suppress discharge of the heat transfer gas, the bias electrode 21 is provided in the first region 20a in the electrostatic chuck 20, and the bias electrode 25 is provided in the second region 20b. This makes it possible to increase 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.

[0046] The impedance Z of the high frequency current that flows when the high frequency power LF is applied to the bias electrode 21 and the bias electrode 25 of the electrostatic chuck 20 is expressed by the following equation. Z=-(1 / Cω)×j Therefore, it is possible to reduce the impedance Z of the high frequency current flowing through the electrostatic chuck 20 by increasing the electrostatic capacitance C. As a result, the potential difference between the substrate W and the bias electrode 21 becomes smaller.

[0047] In addition, the time constant τ in an RC circuit is expressed by the following equation. τ=RC Therefore, when RC is small, the potential is easily changed. Therefore, by increasing the capacitance C, RC is increased, and the fluctuation of the potential on the substrate W and the edge ring 26 can be suppressed.

[0048] For example, when the state of the bias electrode 21 momentarily becomes −5000 V, the substrate W also momentarily becomes −5000 V. At this time, ions in the plasma are attracted to the substrate W, so that 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 this 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. This makes it possible to increase 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, as compared with the case where high frequency LF power is applied to the electrode plate 16. This makes it possible to reduce the potential difference between the substrate W and the edge ring 26, and to suppress fluctuations in the potential of the substrate W and the edge ring 26. This makes it possible to suppress discharge of the heat transfer gas supplied to the rear surface of the substrate W. As a result, it is possible to suppress abnormal discharge from occurring on the rear surface of the substrate W and the rear surface of the edge ring 26.

[0050] It is also 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. This makes it possible to make the capacitance between the bias electrode 21 and the substrate W and the capacitance between the bias electrode 25 and the edge ring 26 approximately equal. This makes it possible to reduce or eliminate the potential difference between the substrate W and the edge ring 26, and more effectively suppress the occurrence of abnormal discharge between the substrate W and the edge ring 26.

[0051] An adhesive layer is provided between the lower electrode 18 and the electrostatic chuck 20 to bond the lower electrode 18 and the electrostatic chuck 20. When a high frequency LF is applied to the electrode plate 16 as in the conventional case, the adhesive layer having a low dielectric constant prevents the capacitance between the bias electrode 21 and the substrate W and the capacitance between the bias electrode 25 and the edge ring 26 from being increased.

[0052] In contrast, 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. With this, the absence of an adhesive layer makes it possible to increase the electrostatic capacitance between the bias electrode 21 and the substrate W, and between the bias electrode 25 and the edge ring 26, and also allows for a free design regarding heat transfer and stress relaxation of the adhesive layer.

[0053] Although the high frequency HF power for generating plasma is applied to the electrode plate 16, it may 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 AA cross section of the electrostatic chuck 20 shown in Fig. 2. Fig. 3(b) is a diagram showing a BB cross section of the electrostatic chuck 20. Fig. 3(c) is a diagram showing a CC cross section of the electrostatic chuck 20.

[0055] 3(a), a circular chucking electrode 23 is provided in the circular first region 20a. The chucking electrode 23 is a film-like or sheet-like electrode.

[0056] 3B, the second region 20b is provided with annular chucking electrodes 27a and 27b. Each of the chucking electrodes 27a and 27b is a film-like or sheet-like electrode. The chucking electrode 27b is provided on the outer side of the chucking electrode 27a.

[0057] Further, a circular bias electrode 21 is provided inside the attraction electrode 27a and in the first region 20a. The bias electrode 21 is in a sheet or mesh shape. The bias electrode 21 is made of conductive ceramics containing ceramics and metal used in the electrostatic chuck 20.

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

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

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

[0061] Furthermore, in consideration of 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 metal. This can mitigate 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 heat input from the plasma, and reduce friction between the bias electrode 21 and the electrostatic chuck 20.

[0062] Referring to the CC cross section of FIG. 3(c), a ring-shaped 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 has power supply terminals 25a evenly arranged in the circumferential direction. This makes it possible to equalize the impedance of the high frequency LF in the circumferential direction, and to reduce the bias of the high frequency LF in the circumferential direction.

[0063] The bias electrode 25 has a sheet or mesh shape and is made of the same conductive ceramic material used in the electrostatic chuck 20, which contains ceramic and metal.

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

[0065] Furthermore, bias electrode 25 may be made of a metal mesh rather than a sheet. This can reduce the difference in contraction between bias electrode 25 and electrostatic chuck 20 caused by the difference in linear expansion coefficient between bias electrode 25 and electrostatic chuck 20 due to heat input from plasma, and can reduce friction between bias electrode 25 and electrostatic chuck 20.

[0066] As described above, according to the mounting table 14 and plasma processing apparatus 1 of this embodiment, by providing the bias electrodes 21, 25 within 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.

[0067] The above disclosed embodiments include, for example, the following aspects. (Appendix 1) an electrostatic chuck for supporting the substrate and the edge ring; A base supporting the electrostatic chuck, The electrostatic chuck comprises: a first region having a first top surface and configured to support a substrate disposed on the first top surface; a second region having a second top surface, the second region being integrally disposed around the first region and configured to support an edge ring disposed on the second top surface; a first electrode provided in the first region and configured to apply a DC voltage; a second electrode provided in the second region and configured to apply a DC voltage; a third electrode for applying a bias power; A mounting table having (Appendix 2) 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 are controlled independently. 2. The mounting table according to claim 1. (Appendix 3) the 3-1 electrode and the second electrode are disposed on the same surface of the electrostatic chuck; Attachment 2. A mounting table as described in appendix 2. (Appendix 4) a thickness from the first upper surface to the 3-1 electrode is equal to a thickness from the second upper surface to the 3-2 electrode; 4. The mounting table according to claim 2 or 3. (Appendix 5) The electrostatic chuck is formed of a dielectric material, The base is formed of a metal. The mounting table according to any one of claims 1 to 4. (Appendix 6) The third electrode is in a sheet or mesh shape having a sheet resistance equal to or lower than a predetermined value. The mounting table according to any one of claims 1 to 5. (Appendix 7) The third electrode is formed of a conductive ceramic containing the ceramic and metal used in the electrostatic chuck. The mounting table according to any one of claims 1 to 6. (Appendix 8) a first high frequency power supply that applies high frequency power for generating plasma; a second high frequency power supply and a third high frequency power supply that apply bias power for attracting ions; an electrostatic chuck for supporting the substrate and the edge ring; A base supporting the electrostatic chuck, The electrostatic chuck comprises: a first region having a first top surface and configured to support a substrate disposed on the first top surface; a second region having a second top surface, the second region being integrally disposed around the first region and configured to support an edge ring disposed on the second top surface; a first electrode provided in the first region and configured to apply a DC voltage; a second electrode provided in the second region and configured to apply a DC voltage; a third electrode for applying a bias power; The plasma processing apparatus comprises:

[0068] The mounting table and plasma processing apparatus according to the present disclosure should be considered as illustrative in all respects and not restrictive. The above-described embodiment can be modified and improved in various forms without departing from the scope and spirit of the appended claims. The matters described in the above-described embodiments can be configured in other ways without any contradiction, and can be combined without any contradiction.

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

[0070] The plasma processing apparatus may be an apparatus that performs a predetermined process (eg, etching process, film formation process, etc.) on a substrate. [Explanation of symbols]

[0071] Reference Signs List 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 electrode, 26...edge ring, 23, 27a, 27b...chucking 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

Claims

1. a plasma processing chamber; a mounting table disposed within the plasma processing chamber, the mounting table including a substrate mounting portion having a first upper surface on which a substrate is mounted and an edge ring mounting portion having a second upper surface on which an edge ring surrounding the substrate is mounted and disposed on the first upper surface; a first bias electrode disposed within the substrate placement portion; a second bias electrode disposed within the edge ring mounting portion; a first bias power supply electrically connected to the first bias electrode; a second bias power supply electrically connected to the second bias electrode; a distance between the second upper surface of the edge ring mounting part and an upper surface of the second bias electrode is equal to a distance between the first upper surface of the substrate mounting part and an upper surface of the first bias electrode; Plasma processing equipment.

2. The mounting table includes an electrostatic chuck. the first bias electrode is disposed within the electrostatic chuck. The plasma processing apparatus according to claim 1 .

3. The mounting table includes an electrostatic chuck. the second bias electrode is disposed within the electrostatic chuck.

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

4. an adsorption electrode for the edge ring is disposed above the second bias electrode within the electrostatic chuck; the attraction electrode and the first bias electrode are disposed in the same plane; 4. The plasma processing apparatus according to claim 2 or 3.

5. the chucking electrodes include a first chucking electrode and a second chucking electrode, voltages having polarities different from each other are applied to the first chucking electrode and the second chucking electrode; The plasma processing apparatus according to claim 4 .

6. A plurality of power supply terminals are arranged in a circumferential direction on the second bias electrode. The plasma processing apparatus according to any one of claims 3 to 5.

7. The plurality of power supply terminals are arranged evenly in the circumferential direction. The plasma processing apparatus according to claim 6 .

8. The first bias power supply is at least one of a DC power supply, a high frequency power supply, and a pulse power supply. The plasma processing apparatus according to any one of claims 1 to 7.

9. The second bias power supply is at least one of a DC power supply, a high frequency power supply, and a pulse power supply. The plasma processing apparatus according to any one of claims 1 to 8.

10. the first bias power supply is a negative DC pulse power supply; The plasma processing apparatus according to claim 8 .

11. the second bias power supply is a negative DC pulse power supply; The plasma processing apparatus according to claim 9 or 10.

12. A mounting table disposed in a plasma processing chamber, comprising: a substrate placement portion having a first upper surface on which a substrate is placed; an edge ring mounting portion having a second upper surface on which an edge ring is placed to surround the substrate disposed on the first upper surface; a first bias electrode disposed within the substrate placement portion and electrically connected to a first bias power supply; a second bias electrode disposed within the edge ring mount and electrically connected to a second bias power supply; a distance between the second upper surface of the edge ring mounting part and an upper surface of the second bias electrode is equal to a distance between the first upper surface of the substrate mounting part and an upper surface of the first bias electrode; Mounting stand.

13. the substrate placement portion and the edge ring placement portion constitute an electrostatic chuck. The mounting table according to claim 12 .

14. an adsorption electrode for the edge ring is disposed above the second bias electrode within the electrostatic chuck; the attraction electrode and the first bias electrode are disposed in the same plane; The mounting table according to claim 13 .

15. the chucking electrodes include a first chucking electrode and a second chucking electrode, voltages having polarities different from each other are applied to the first chucking electrode and the second chucking electrode; The mounting table according to claim 14 .

16. A plurality of power supply terminals are arranged in a circumferential direction on the second bias electrode. The mounting table according to any one of claims 13 to 15.

17. The plurality of power supply terminals are arranged evenly in the circumferential direction. The mounting table according to claim 16.

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