Substrate support and substrate processing apparatus

Abstract

The amount of wear of an edge ring supported by a substrate support during plasma processing is appropriately reduced. [Solution] A mounting table (11) as a substrate support for supporting a substrate (W) and an edge ring (13) on its upper surface includes a substrate support section consisting of an electrostatic chuck (112) that attracts the substrate, a ring holding member (113) that supports an edge ring arranged to surround the substrate and has a heater electrode (113b) for the edge ring inside, a base (111) having a central mounting section (111c) on which the substrate support section is arranged and an outer peripheral mounting section (111e) on the outer periphery of the central mounting section on which the ring holding member is arranged, a first power supply terminal (112c) arranged directly below the substrate support section and that supplies power to the heater electrode (112b) for the substrate, and a second power supply terminal (113b) arranged directly below the ring holding member and that supplies power to the heater electrode for the edge ring, the upper surface of the outer peripheral mounting section being lower than the upper surface of the central mounting section, and the thickness of the ring support section being 40% or more of the thickness of the substrate support section.

Description

Technical Field

[0001] The present disclosure relates to a substrate support and a substrate processing apparatus.

Background Art

[0002] Patent Document 1 discloses a substrate processing apparatus including a base disposed inside a processing chamber and having a refrigerant flow path provided therein extending to an inlet and an outlet, and a mounting table having an electrostatic chuck provided on an upper surface of the base via an adhesive and having a heater provided inside or on a lower surface thereof.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure appropriately reduces the consumption amount during plasma processing of an edge ring disposed around a substrate supported by a substrate support.

Means for Solving the Problems

[0005] One aspect of the present disclosure is a substrate support for supporting a substrate and an edge ring on its upper surface, comprising: a substrate support portion having an electrostatic chuck for adsorbing the substrate and a heater electrode for the substrate within the electrostatic chuck; a ring support portion supporting an edge ring arranged to surround the substrate and having a heater electrode for the edge ring inside; a base material having a central mounting portion on which the substrate support portion is arranged and an outer peripheral mounting portion on the outer periphery side of the central mounting portion on which the ring support portion is arranged; a first power supply terminal disposed directly below the substrate support portion and supplying power to the heater electrode for the substrate; and a second power supply terminal disposed directly below the ring support portion and supplying power to the heater electrode for the edge ring, wherein the upper surface of the outer peripheral mounting portion is lower than the upper surface of the central mounting portion, and the thickness of the ring support portion is 40% or more of the thickness of the substrate support portion. [Effects of the Invention]

[0006] According to this disclosure, in an edge ring disposed around a substrate supported by a substrate support, the amount of wear on the edge ring during plasma treatment can be appropriately reduced. [Brief explanation of the drawing]

[0007] [Figure 1] This is a schematic longitudinal cross-sectional view showing the general configuration of the plasma processing system according to this embodiment. [Figure 2] This is a schematic longitudinal cross-sectional view showing the general configuration of the mounting platform according to this embodiment. [Figure 3] Figure 2 is an enlarged view showing the main parts of the mounting platform. [Figure 4] This is a plan view showing an example of dividing a temperature-controlled area into regions where the temperature is independently controlled by heaters. [Figure 5] Figure 2 is a close-up view of a key part showing another example of the placement of the sealing member in the substrate support shown. [Figure 6] Figure 2 is a close-up view of a key part showing another example of the placement of the sealing member in the substrate support shown. [Modes for carrying out the invention]

[0008] In the semiconductor device manufacturing process, a plasma processing apparatus generates plasma by exciting a processing gas, and uses this plasma to process a semiconductor substrate (hereinafter referred to as "substrate") placed on a mounting table. The mounting table on which the substrate is placed is equipped with an electrostatic chuck that holds the substrate to the mounting surface by attraction, for example, Coulomb force.

[0009] Incidentally, as disclosed in Patent Document 1, the mounting platform located inside the chamber of the plasma processing apparatus is provided with an edge ring (also called a "focus ring") that surrounds the substrate held by adsorption on the mounting surface. This edge ring is exposed to the internal space of the chamber (plasma processing space) during plasma processing, and therefore wears down due to the influence of the plasma generated in the plasma processing space.

[0010] One possible countermeasure against edge ring wear during plasma processing is to increase the thickness of the edge ring itself or the thickness of the ring-holding member that holds the edge ring on the mounting platform. For example, increasing the thickness of the edge ring itself increases the margin of wear before it reaches a thickness that requires replacement, thus extending the lifespan of the edge ring. Alternatively, increasing the thickness of the ring-holding member changes the impedance ratio with respect to the substrate and electrostatic chuck, reducing the amount of plasma acting on the edge ring during plasma processing. In other words, the effect of plasma on the edge ring is reduced, thereby reducing the amount of wear on the edge ring.

[0011] However, in the conventional mounting platform structure disclosed in Patent Document 1, the thickness of the edge ring and ring holding member could not be increased, making it impossible to properly extend the lifespan of the edge ring and reduce its wear. Specifically, in the conventional mounting platform structure such as that disclosed in Patent Document 1, the attachment position of the electrostatic chuck and ring holding member to the base material of the mounting platform could not be changed, meaning that it was difficult to independently change the thickness of the edge ring and ring holding member. Thus, from the viewpoint of reducing the wear of the edge ring and extending its lifespan, there was room for improvement in the conventional mounting platform structure.

[0012] The technology disclosed herein has been made in view of the above circumstances, and appropriately reduces the amount of wear on an edge ring during plasma processing of an edge ring disposed around a substrate supported by a substrate support. A plasma processing system as a substrate processing apparatus equipped with a mounting table according to one embodiment will be described below with reference to the drawings. In this specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals to avoid redundant explanations.

[0013] <Plasma Treatment System> First, the plasma processing system as a substrate processing apparatus according to this embodiment will be described. Figure 1 is a longitudinal cross-sectional view showing a schematic configuration of the plasma processing system 1. The plasma processing system 1 has a capacitively coupled plasma processing apparatus and performs plasma processing on the substrate W to be processed, such as etching, film deposition, and diffusion.

[0014] In one embodiment, the plasma processing system 1 includes a plasma processing apparatus 1a and a control unit 1b. The plasma processing apparatus 1a includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1a also includes a mounting table 11 and an upper electrode shower head 12 according to this embodiment. The mounting table 11 is positioned in the lower region of the plasma processing space 10s within the plasma processing chamber 10. The upper electrode shower head 12 is positioned above the mounting table 11 and may function as part of the ceiling of the plasma processing chamber 10.

[0015] The mounting table 11, which serves as a substrate support, comprises a base material 111, an electrostatic chuck 112 positioned on the upper surface of the central part of the base material 111 and having a mounting surface for the substrate W, and a ring holding member 113 positioned on the upper surface of the outer periphery of the base material 111 and having a mounting surface for the edge ring 13 described later. The mounting table 11 is fixed to the floor of the plasma processing chamber 10 via a mounting base 114. The detailed configuration of the mounting table 11 will be described later.

[0016] An annular edge ring 13 is provided on the mounting surface of the ring holding member 113, surrounding the mounting surface of the substrate W of the electrostatic chuck 112 in a plan view. In one example, the edge ring 13 is provided to improve the uniformity of the plasma treatment. The edge ring 13 is made of a material appropriately selected depending on the plasma treatment to be performed, and may be made of silicon, silicon carbide (SiC), or quartz, for example.

[0017] Furthermore, it is preferable that the upper surface of the substrate W placed on the mounting surface of the electrostatic chuck 112 and the upper surface of the edge ring 13 placed on the mounting surface of the ring holding member 113 substantially coincide in a plan view, as shown in Figure 1.

[0018] The upper electrode shower head 12 is configured to supply one or more process gases from the gas supply unit 20 to the plasma processing space 10s. In one embodiment, the upper electrode shower head 12 has a gas inlet 12a, a gas diffusion chamber 12b, and a plurality of gas outlets 12c. The gas inlet 12a is in fluid communication with the gas supply unit 20 and the gas diffusion chamber 12b. The plurality of gas outlets 12c are in fluid communication with the gas diffusion chamber 12b and the plasma processing space 10s. In one embodiment, the upper electrode shower head 12 is configured to supply one or more process gases from the gas inlet 12a to the plasma processing space 10s via the gas diffusion chamber 12b and the plurality of gas outlets 12c.

[0019] The gas supply unit 20 may include one or more gas sources 21 and one or more flow controllers 22. In one embodiment, the gas supply unit 20 is configured to supply one or more process gases from the respective gas sources 21 to the gas inlet 12a via the respective flow controllers 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Further, the gas supply unit 20 may include one or more flow modulation devices for modulating or pulsing the flow rate of one or more process gases.

[0020] The power supply 30 includes an RF (Radio Frequency) generation unit 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. In one example, the RF generation unit 31 includes a first RF generation unit 31a configured to generate a source RF signal for generating plasma, and a second RF generation unit 31b configured to generate a bias RF signal for drawing ions in the plasma to the substrate W.

[0021] The first RF generation unit 31a is coupled to the mounting stage 11 and / or the upper electrode shower head 12 via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power). This causes plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Thus, the first RF generation unit 31a can function as at least part of the plasma generation unit. In one embodiment, the source RF signal has a frequency of 27 MHz to 100 MHz.

[0022] The second RF generation unit 31b is coupled to the mounting stage 11 via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). The second RF generation unit 31b may be coupled to a substrate 111 that functions as a lower electrode on the mounting stage 11, or to a bias electrode (not shown) provided in the electrostatic chuck 112. When the bias RF signal is supplied to the mounting stage 11, a bias potential is generated on the substrate W, and ions in the plasma can be drawn into the substrate W. The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a lower frequency than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency of 100 kHz to 60 MHz. In one embodiment, the second RF generation unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0023] Furthermore, the power supply 30 may include a DC power supply 32 coupled to the plasma processing chamber 10. For example, the DC power supply 32 includes a first DC generation unit 32a and / or a second DC generation unit 32b. In one embodiment, the first DC generation unit 32a is coupled to the mounting stage 11 and configured to generate a first DC signal. The first DC generation unit 32a, like the bias RF signal, may be coupled to a substrate 111 that functions as a lower electrode, or to a bias electrode provided in the electrostatic chuck 112. The generated first DC signal is applied to the mounting stage 11. In one embodiment, the second DC generation unit 32b is connected to the upper electrode shower head 12 and configured to generate a second DC signal. The generated second DC signal is applied to the upper electrode shower head 12.

[0024] In various embodiments, at least one of the first DC signal and the second DC signal may be pulsed. In this case, the pulsed first DC signal and / or second DC signal (hereinafter also referred to as "voltage pulse") are applied to the mounting base 11 and / or the upper electrode shower head 12. The voltage pulse may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generation unit for generating a voltage pulse from a DC signal is connected between the first DC generation unit 32a and the mounting base 11. Thus, the first DC generation unit 32a and the waveform generation unit constitute a voltage pulse generation unit. When the second DC generation unit 32b and the waveform generation unit constitute a voltage pulse generation unit, the voltage pulse generation unit is connected to the upper electrode shower head 12. The voltage pulse may have positive polarity or negative polarity. The first DC generation unit 32a may be provided together with the second RF generation unit 31b, or it may be provided in place of the second RF generation unit 31b.

[0025] The exhaust system 40 may be connected to, for example, an exhaust port 10e located at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure valve and a vacuum pump. The vacuum pump may include a turbomolecular pump, a roughing pump, or a combination thereof.

[0026] In one embodiment, the control unit 1b processes computer-executable instructions causing the plasma processing apparatus 1a to perform various processes described herein. The control unit 1b may be configured to control each element of the plasma processing apparatus 1a to perform the various processes described herein. In one embodiment, some or all of the control unit 1b may be included in the plasma processing apparatus 1a. The control unit 1b may include, for example, a computer 51. The computer 51 may include, for example, a processing unit (CPU: Central Processing Unit) 511, a storage unit 512, and a communication interface 513. The processing unit 511 may be configured to perform various control operations based on a program stored in the storage unit 512. The storage unit 512 may include RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof. The communication interface 513 may communicate with the plasma processing apparatus 1a via a communication line such as a LAN (Local Area Network).

[0027] <Mounting platform> Next, the detailed configuration of the mounting base 11 described above will be explained. Figure 2 is a schematic longitudinal cross-sectional view showing the general configuration of the mounting base 11. Figure 3 is an enlarged view of the main part showing the outer periphery of the mounting base 11 shown in Figure 2. As shown in Figure 2, the mounting base 11 according to this embodiment has a base material 111, an electrostatic chuck 112, and a ring holding member 113.

[0028] The upper surface of the central part of the base material 111 forms a central mounting portion 111c for mounting the electrostatic chuck 112. The upper surface of the outer periphery of the base material 111 forms an outer periphery mounting portion 111e for mounting the ring holding member 113. The upper surface height of the central mounting portion 111c is set higher than the upper surface height of the outer periphery mounting portion 111e. In other words, the ring holding member 113 is mounted at a lower position on the base material 111 in a side view compared to the electrostatic chuck 112. Furthermore, it is desirable that the upper surface height position of the central mounting portion 111c be set higher than the upper surface height position of the ring holding member 113 mounted on the outer periphery mounting portion 111e, as shown in Figure 3.

[0029] A refrigerant channel 111a is formed inside the substrate 111. A chiller unit (not shown) is connected to the refrigerant channel 111a, and by circulating the refrigerant (e.g., cooling water) supplied from the chiller unit inside, the mounting base 11 and the substrate W placed on the mounting base 11 are cooled to a desired temperature.

[0030] The base material 111 is made of, for example, aluminum or ceramic, and functions as a lower electrode in the plasma processing system 1.

[0031] The electrostatic chuck 112, which constitutes the substrate support portion, is placed on the central mounting portion 111c of the base material 111, for example, via an adhesive layer (not shown). The electrostatic chuck 112 has a mounting surface on its upper surface for electrostatically adsorbing the substrate W. The electrostatic chuck 112 is made of a dielectric material such as ceramic (hereinafter also referred to as the "first dielectric").

[0032] Inside the electrostatic chuck 112, in addition to a substrate adsorption electrode 112a for adsorbing the substrate W, a substrate heater electrode 112b for heating the substrate W is provided.

[0033] A DC power supply (not shown; hereinafter also referred to as the "adsorption power supply") is connected to the substrate adsorption electrode 112a, for example, via a switch. The electrostatic chuck 112 can adsorb and hold the substrate W to the mounting surface by the Coulomb force generated when a DC voltage is applied from the adsorption power supply to the substrate adsorption electrode 112a.

[0034] A power supply (not shown; hereinafter also referred to as the "first heater power supply") is connected to the substrate heater electrode 112b, for example, via a switch. The power supply may be a DC power supply or an AC power supply. The substrate heater electrode 112b may be located below the substrate adsorption electrode 112a and above the aforementioned refrigerant flow path 111a. The substrate heater electrode 112b is heated by power supplied from the first heater power supply, thereby adjusting the substrate W placed on the electrostatic chuck 112 to a desired temperature. In this embodiment, the electrostatic chuck 112 may be divided into multiple regions in a plan view. These multiple regions may be, for example, the substrate temperature control regions Z shown in Figure 4. The substrate heater electrode 112b may be composed of multiple segment electrodes. In this case, each of the multiple segment electrodes may be arranged in each of the multiple regions. In such a configuration, the amount of power supplied to each segment electrode may be independently controllable by the control unit 1b. This allows the temperature of the substrate W to be adjusted independently for each substrate temperature control region Z. Note that the number and shape of the substrate temperature control regions Z are not limited to the illustrated example and can be set arbitrarily.

[0035] In one embodiment, the electrostatic chuck 112 may consist of a first dielectric and a first electrode within the first dielectric. The first electrode may include at least one electrode selected from the group consisting of a substrate adsorption electrode, a substrate heater electrode, and a substrate bias electrode. In one example, the electrostatic chuck 112 consists of a first dielectric and a substrate adsorption electrode and a substrate bias electrode within the first dielectric. The substrate bias electrode may be connected, for example, to a second RF generation unit 31b or a first DC generation unit 32a via a switch. By supplying a bias RF signal or a first DC signal to the substrate bias electrode during plasma processing, ions in the plasma can be attracted to the substrate W. In one embodiment, the electrostatic chuck 112 may further include a substrate heater electrode in addition to the substrate adsorption electrode and the substrate bias electrode within the first dielectric.

[0036] As shown in Figure 2, a first power supply terminal 112c is positioned below the electrostatic chuck 112. The first power supply terminal 112c may be positioned directly below the electrostatic chuck 112. The first power supply terminal 112c may be positioned in a through-hole that penetrates the central mounting portion 111c of the substrate 111 in the thickness direction. The first power supply terminal 112c is configured to supply power to the substrate heater electrode 112b positioned inside the electrostatic chuck 112. The first power supply terminal 112c may be configured to supply power to the substrate adsorption electrode 112a and / or the substrate bias electrode together with the substrate heater electrode 112b, or in place of the substrate heater electrode 112b. That is, the first power supply terminal 112c may be configured to supply power to at least one electrode selected from the group consisting of the substrate adsorption electrode, the substrate heater electrode, and the substrate bias electrode.

[0037] The ring holding member 113, which serves as the ring support portion, is placed on the outer peripheral mounting portion 111e of the mounting base 11, for example, via an adhesive layer (not shown). The ring holding member 113 may be configured to support the edge ring 13 via an adhesive (not shown) such as a polymer sheet. The ring holding member 113 is made of a dielectric material such as ceramic (hereinafter also referred to as the "second dielectric").

[0038] Inside the ring holding member 113, there is an edge ring heater electrode 113a for heating the edge ring 13.

[0039] A power source (not shown; hereinafter also referred to as the "second heater power source") is connected to the edge ring heater electrode 113a, for example, via a switch. The power source may be a DC power source or an AC power source. The second heater power source may be the same as or different from the first heater power source. The edge ring heater electrode 113a heats up when power is supplied from the second heater power source, thereby adjusting the edge ring 13 placed on the ring holding member 113 to a desired temperature. In this embodiment, the edge ring heater electrode 113a may be arranged circumferentially inside the ring holding member 113. The number, shape, and arrangement of the edge ring heater electrodes 113a are not limited and can be determined arbitrarily. For example, multiple ring-shaped electrodes with different radii may be prepared as the edge ring heater electrodes 113a, and these ring-shaped electrodes may be arranged concentrically inside the ring holding member 113.

[0040] In one embodiment, the ring holding member 113 may consist of a second dielectric and a second electrode within the second dielectric. The second electrode may include at least one electrode selected from the group consisting of an edge ring adsorption electrode, an edge ring heater electrode, and an edge ring bias electrode. Alternatively, the second electrode may include at least two electrodes selected from the group consisting of an edge ring adsorption electrode, an edge ring heater electrode, and an edge ring bias electrode. In one example, the ring holding member 113 consists of a second dielectric and an edge ring bias electrode within the second dielectric. The edge ring bias electrode may be connected, for example, to a second RF generation unit 31b or a first DC generation unit 32a via a switch. By supplying a bias RF signal or a first DC signal to the edge ring bias electrode during plasma processing, ions in the plasma can be attracted to the edge ring 13. In one embodiment, the ring holding member 113 may further include an edge ring heater electrode in addition to the edge ring bias electrode within the second dielectric. Furthermore, as will be described later, if the ring holding member 113 is configured to support the edge ring 13 by an electrostatic chuck, an adsorption electrode for the edge ring may be further provided within the second dielectric.

[0041] As shown in Figure 2, a second power supply terminal 113b is positioned below the ring holding member 113. The second power supply terminal 113b may be positioned directly below the ring holding member 113. The second power supply terminal 113b may be positioned in a through hole that penetrates the outer peripheral mounting portion 111e of the base material 111 in the thickness direction. The second power supply terminal 113b is configured to supply power to the edge ring heater electrode 113a positioned inside the ring holding member 113. The second power supply terminal 113b may be configured to supply power to the edge ring adsorption electrode and / or edge ring bias electrode together with the edge ring heater electrode 113a, or in place of the edge ring heater electrode 113a. That is, the second power supply terminal 113b may be configured to supply power to at least one electrode selected from the group consisting of the edge ring adsorption electrode, the edge ring heater electrode, and the edge ring bias electrode.

[0042] In this embodiment, the edge ring 13 is placed on the outer peripheral mounting portion 111e of the ring holding member 113 via an adhesive, but the method of placing the edge ring 13 is not limited to this. For example, an adsorption electrode for the edge ring may be provided inside the ring holding member 113, and the edge ring 13 may be held in place by adsorption using Coulomb force by applying a DC voltage to the electrode. In other words, the ring holding member 113 may be composed of an annular electrostatic chuck.

[0043] As mentioned above, it is desirable that the upper surface height of the edge ring 13, which is placed on the upper surface of the ring holding member 113, be approximately the same as the upper surface height of the substrate W, which is placed on the upper surface of the electrostatic chuck 112. In other words, it is desirable that the thickness of the ring holding member 113 and the edge ring 13 be determined so that the upper surface height of the edge ring 13 and the upper surface height of the substrate W are approximately the same.

[0044] Furthermore, the mounting base 11 may have a gas channel (not shown) for supplying a heat transfer gas (backside gas), such as helium gas, to the back surface of the substrate W placed on the mounting surface. A gas supply source (not shown) is connected to the gas channel. By supplying the heat transfer gas from the gas supply source, the substrate W placed on the mounting base 11 may be controlled to a desired temperature.

[0045] As mentioned above, the electrostatic chuck 112 and the ring holding member 113 are placed on the upper surface of the base material 111 via an adhesive layer. However, this adhesive layer is consumed by radicals generated during plasma treatment, which may cause the electrostatic chuck 112 and the ring holding member 113 to peel off from the base material 111. Therefore, it is preferable to provide a sealing member 115 (e.g., an O-ring) on ​​the mounting base 11 to protect the adhesive layer from plasma treatment (radicals). The sealing member 115 may be sandwiched between two or more of the electrostatic chuck 112, the ring holding member 113, and the central mounting portion 111c of the base material 111. For example, as shown in Figure 3, if the upper surface height position of the central mounting portion 111c is set higher than the upper surface height position of the ring holding member 113, an electrostatic chuck 112 with a larger diameter than the central mounting portion 111c of the base material 111 may be used, and the sealing member 115 may be provided in the overlapping portion of the electrostatic chuck 112 and the ring holding member 113 in a plan view. In this configuration, when the substrate W is subjected to plasma treatment, the exposure of the adhesive layer to the plasma can be reduced, thereby suppressing wear of the adhesive layer.

[0046] Furthermore, the arrangement of the sealing member 115 is not limited to the example shown in Figure 3, as long as it suppresses the wear of the adhesive layer by radicals.

[0047] For example, as shown in Figure 5, the sealing member 115 may be installed by sandwiching it from the left and right (horizontal) directions between the electrostatic chuck 112 and the ring holding member 113. In this case, a notch N for holding the sealing member 115 may be formed at the contact portion between the sealing member 115 and the ring holding member 113, that is, on the upper part of the inner circumferential surface of the ring holding member 113.

[0048] Alternatively, as shown in Figure 6, the sealing member 115 may be installed by clamping it from above and below and from left and right (horizontally) by the electrostatic chuck 112 and the ring holding member 113. In this case, a notch N for holding the sealing member 115 may be formed on the upper part of the inner circumferential surface of the ring holding member 113.

[0049] Although various exemplary embodiments have been described above, the invention is not limited to the exemplary embodiments described above, and various additions, omissions, substitutions, and modifications may be made. Furthermore, it is possible to combine elements from different embodiments to form other embodiments.

[0050] <Effects and Effects of the Mounting Platform According to This Embodiment> According to the mounting base 11 of this embodiment, the height position of the outer peripheral mounting portion 111e of the base material 111 is set lower than that of the central mounting portion 111c. As a result, the electrostatic chuck 112 for mounting the substrate W on its upper surface and the ring holding member 113 for mounting the edge ring 13 on its upper surface are configured as separate components. Consequently, the thickness of the ring holding member 113 that holds the edge ring 13, and the thickness of the edge ring 13 itself, can be changed independently of the electrostatic chuck 112.

[0051] In this embodiment, it is desirable to determine the thickness of the ring holding member 113 and the edge ring 13 such that the upper surface height of the edge ring 13 and the upper surface height of the substrate W are approximately the same. In this case, as described above, the height position of the outer peripheral mounting portion 111e is set lower than the height position of the central mounting portion 111c, so that at least one of the thicknesses of the ring holding member 113 and the edge ring 13 relative to the thickness of the electrostatic chuck 112 can be set to be larger than in the conventional method.

[0052] Specifically, as described above, by setting the height of the central mounting portion 111c higher than the upper surface height of the ring holding member 113 mounted on the outer peripheral mounting portion 111e, as shown in Figure 3, the thickness of the edge ring 13 itself can be made larger than in the conventional design, and more specifically, greater than or equal to the thickness of the electrostatic chuck 112. By increasing the thickness of the edge ring 13 in this way, the lifespan of the edge ring 13 can be appropriately extended.

[0053] More specifically, by increasing the thickness of the ring holding member 113 (edge ​​ring 13) in this way, the impedance ratio of the ring holding member 113 (edge ​​ring 13) to the electrostatic chuck 112 can be adjusted. In other words, the heat input ratio to the edge ring 13 during plasma processing can be reduced, thereby reducing the wear on the edge ring 13 and extending its lifespan more effectively.

[0054] The inventors conducted thorough research and found that, from the viewpoint of the amount of wear on the edge ring 13 and the strength of the ring holding member 113, it is desirable that the thickness of the ring holding member 113 be at least 40% of the thickness of the electrostatic chuck 112, preferably 50% or more. Based on this finding, by forming the ring holding member 113, which was conventionally formed to be about half the thickness of the electrostatic chuck 112, to be, for example, approximately the same thickness as the electrostatic chuck 112, the heat input ratio to the edge ring 13 (amount of wear on the edge ring 13) could be reduced by about 10%.

[0055] Furthermore, in order to properly perform plasma treatment on the substrate W in the plasma treatment system 1, it is necessary to maintain uniform in-plane temperature of the substrate W placed on the electrostatic chuck 112, and to maintain a desired temperature difference between the substrate W and the edge ring 13.

[0056] In this respect, according to this embodiment, as described above, the electrostatic chuck 112 on which the substrate W is placed and the ring holding member 113 on which the edge ring 13 is placed are configured as separate components. As a result, in the plasma processing space 10s inside the plasma processing apparatus 1a, the electrostatic chuck 112 and the ring holding member 113 have a vacuum insulation structure, and the temperatures of the electrostatic chuck 112 and the ring holding member 113 can be controlled independently to maintain an appropriate temperature difference between the substrate W and the edge ring 13.

[0057] Furthermore, according to the embodiment shown in Figure 4, the electrostatic chuck 112 (substrate W) is configured so that multiple substrate temperature control regions Z can be independently temperature-controlled by multiple substrate heater electrodes 112b provided inside the electrostatic chuck 112. This makes it possible to appropriately maintain uniformity of the in-plane temperature of the surface (substrate W) of the electrostatic chuck 112.

[0058] Specifically, the inventors' studies showed that they were able to control the surface temperature of the electrostatic chuck 112 to approximately 20°C while maintaining the surface temperature of the ring holding member 113 at approximately 90°C (temperature difference control between the substrate W and the edge ring 13). Furthermore, they were able to control the variation in the surface temperature of the electrostatic chuck 112 to within Δ1.5°C (uniform control of the in-plane temperature of the substrate W). In other words, they were able to ensure uniform in-plane temperature of the substrate W while securing the desired temperature difference between the substrate W and the edge ring 13.

[0059] In the embodiments described above, the ring holding member 113 was described as an example in which a second power supply terminal 113b for applying voltage to the edge ring heater electrode 113a and a DC power supply (not shown) for applying a DC voltage to the edge ring adsorption electrode may be connected. However, the ring holding member 113 may also be further connected to a DC power supply (not shown) for applying a DC voltage to the ring holding member 113 when the edge ring 13 is worn out due to plasma processing, for example.

[0060] If the upper surface height of the edge ring 13 changes due to wear, this will cause a change in the sheath shape formed during plasma processing. Specifically, wear of the edge ring 13 will create a step between the sheath height of the substrate W and the sheath height of the edge ring 13. When the sheath shape changes in this way, the accuracy of the plasma processing may deteriorate.

[0061] Therefore, as described above, when the edge ring 13 is worn out, applying a DC voltage from a DC power supply to the ring holding member 113 can cancel out the change in sheath shape caused by the wear of the edge ring 13. More specifically, by adjusting the DC voltage applied to the edge ring 13 according to the wear of the edge ring 13, the sheath height of the edge ring 13 can be adjusted, thereby making the sheath height of the substrate W and the sheath height of the edge ring 13 the same.

[0062] The method of applying the DC voltage from the DC power supply to the edge ring 13 is not particularly limited. For example, a DC voltage may be applied to the edge ring 13 when the wear of the edge ring 13 is large (when the sheath height of the edge ring 13 is below a predetermined threshold), and the application of the DC voltage may be stopped when the wear of the edge ring 13 is small (when the sheath height of the edge ring 13 exceeds a predetermined threshold).

[0063] Furthermore, if the wear of the edge ring 13 is significant (when the sheath height of the edge ring 13 is below a predetermined threshold), the DC voltage applied to the edge ring 13 may be changed in steps or continuously.

[0064] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The above embodiments may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims.

[0065] For example, in the plasma processing system 1 of the above embodiment, the case in which capacitively coupled plasma (CCP) is generated in the plasma processing apparatus 1a was described as an example, but the plasma generated in the plasma processing apparatus 1a may be, for example, inductively coupled plasma (ICP). [Explanation of symbols]

[0066] 1a Plasma processing apparatus 11. Mounting platform 13 Edge Ring 111 Base material 111c Center placement part 111e Outer holder 112 Electrostatic Chuck 112b Heater electrodes for substrates 112c First power supply terminal 113 Ring holding member 113a Heater electrode for edge ring 113b Second power supply terminal W board

Claims

1. A substrate support, A substrate support portion including a first dielectric having a substrate mounting surface, and a first electrode within the first dielectric, A ring support member having a ring mounting surface for supporting an edge ring arranged to surround the substrate mounting surface, A base material including a central mounting portion on which the substrate support portion is arranged, and an outer peripheral mounting portion on which the ring support member is arranged, Equipped with, The substrate mounting surface has a larger diameter than the central mounting portion. The upper surface of the outer peripheral mounting portion is located at a lower position than the upper surface of the central mounting portion. The inner diameter of the ring support member is smaller than the inner diameter of the edge ring. The substrate support portion and the ring support member are separate components, and in a plan view, the substrate mounting surface and the ring support member overlap. The inner edge of the ring support member overlaps with the outer edge of the substrate support portion in a plan view. The outer edge of the substrate support portion is spaced upward from the inner edge of the ring support member. Substrate support.

2. The ring support member includes a second dielectric, In the inner edge of the ring support member, the second dielectric overlaps with the outer edge of the substrate support portion in a plan view. The outer edge of the substrate support portion is spaced upward from the second dielectric at the inner edge of the ring support member. The substrate support according to claim 1.

3. The ring support member comprises a second electrode within the second dielectric, The second electrode includes at least one electrode selected from the group consisting of an edge ring adsorption electrode, an edge ring heater electrode, and an edge ring bias electrode. The substrate support according to claim 2.

4. The ring support member comprises a second electrode within the second dielectric, The second electrode includes at least two electrodes selected from the group consisting of an edge ring adsorption electrode, an edge ring heater electrode, and an edge ring bias electrode. The substrate support according to claim 2.

5. The substrate support according to claim 3 or 4, wherein at least a portion of the second electrode, which is positioned on the outermost periphery, is located further outward than the first electrode, which is positioned on the outermost periphery.

6. The substrate support according to any one of claims 1 to 5, further comprising a sealing member sandwiched between the lower surface of the outer edge of the substrate support and the upper surface of the inner edge of the ring support member.

7. The upper surface of the ring support member includes the upper surface of the inner edge and the ring mounting surface, and the entire upper surface of the ring support member is flat. The substrate support according to claim 6.

8. The substrate support according to claim 7, wherein the flat lower surface of the edge ring, which extends from the inner edge of the edge ring, is in contact with the ring mounting surface.

9. The substrate support according to any one of claims 1 to 5, further comprising a sealing member disposed between two or more of the substrate support portion, the ring support member, the central mounting portion, and the edge ring.

10. The substrate support according to claim 9, wherein the sealing member is disposed between the substrate support portion and the ring support portion.

11. The substrate support according to any one of claims 1 to 5, further comprising a sealing member in contact with the ring support member.

12. The substrate support according to claim 11, wherein the sealing member and the edge ring are in contact with the same surface of the ring support member.

13. The substrate support includes the edge ring, The edge ring has a first inner diameter surface with the smallest diameter and a second inner diameter surface with the largest diameter. In a radial view, the outer diameter surface with the largest diameter of the substrate support portion and the first inner diameter surface overlap. A substrate support according to any one of claims 6 to 12.

14. The substrate support includes the edge ring, The edge ring has a first inner diameter surface with the smallest diameter and a second inner diameter surface with the largest diameter. In a radial view, the outer diameter surface with the largest diameter of the substrate support portion and the first inner diameter surface overlap. The substrate support according to claim 9, 11, or 12, wherein the sealing member is disposed between the substrate support portion and the edge ring.

15. The substrate support according to any one of claims 1 to 14, wherein the first electrode includes at least one electrode selected from the group consisting of a substrate adsorption electrode, a substrate heater electrode, and a substrate bias electrode.

16. A processing chamber that processes the substrate internally, A plasma generation unit that generates plasma within the processing chamber, A substrate support is disposed inside the processing chamber and supports the substrate, Equipped with, The substrate support is A substrate support portion including a first dielectric having a substrate mounting surface, and a first electrode within the first dielectric, A ring support member having a ring mounting surface for supporting an edge ring arranged to surround the substrate mounting surface, A base material including a central mounting portion on which the substrate support portion is arranged, and an outer peripheral mounting portion on which the ring support member is arranged, Includes, The substrate mounting surface has a larger diameter than the central mounting portion. The upper surface of the outer peripheral mounting portion is located at a lower position than the upper surface of the central mounting portion. The inner diameter of the ring support member is smaller than the inner diameter of the edge ring. The substrate support portion and the ring support member are separate components, and in a plan view, the substrate mounting surface and the ring support member overlap. The inner edge of the ring support member overlaps with the outer edge of the substrate support portion in a plan view. The outer edge of the substrate support portion is spaced upward from the inner edge of the ring support member. Circuit board processing equipment.

17. The ring support member includes a second dielectric, In the inner edge of the ring support member, the second dielectric overlaps with the outer edge of the substrate support portion in a plan view. The outer edge of the substrate support portion is spaced upward from the second dielectric at the inner edge of the ring support member. The substrate processing apparatus according to claim 16.

18. The substrate processing apparatus according to claim 16 or 17, further comprising a sealing member sandwiched between the lower surface of the outer edge of the substrate support and the upper surface of the inner edge of the ring support member.

19. The upper surface of the ring support member includes the upper surface of the inner edge and the ring mounting surface, and the entire upper surface of the ring support member is flat. The substrate processing apparatus according to claim 18.

20. The substrate processing apparatus according to claim 19, wherein the flat lower surface of the edge ring, which extends from the inner edge of the edge ring, is in contact with the ring mounting surface.

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