Mounting table and plasma processing apparatus

Abstract

The present invention provides a mounting table and a plasma processing apparatus. Deposits on the groove are reduced. The mounting table includes an electrostatic chuck, a base, and a shield. The electrostatic chuck adsorbs a substrate. The base is divided by a groove extending in a ring shape into a first region that supports the electrostatic chuck and a second region that supports an edge ring disposed around the substrate. The shield is provided in the groove, and thermally separates the first region from the second region.

Description

Technical Field

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

[0002] Patent Document 1 discloses a mounting table configured to have a groove between a region for mounting a substrate and a region of a focus ring around the substrate, and capable of increasing a temperature difference.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2016 - 27601 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] The present disclosure provides a technique for reducing deposition of deposits in a groove.

[0008] Solutions for Solving the Problems

[0009] One aspect of the present disclosure is a mounting table for mounting a substrate. The mounting table has an electrostatic chuck, a base, and a shield. The electrostatic chuck adsorbs the substrate. The base is divided by a groove extending in a ring shape into a first region that supports the electrostatic chuck and a second region that supports an edge ring disposed around the substrate. The shield is provided in the groove, and thermally separates the first region from the second region.

[0010] Effects of the Invention

[0011] According to the present disclosure, deposition of deposits in the groove can be reduced. Brief Description of the Drawings

[0012] Figure 1 is a schematic cross-sectional view showing a schematic structure of a plasma processing apparatus according to the first embodiment.

[0013] Figure 2 is a schematic cross-sectional view showing a main part structure of the mounting table according to the first embodiment.

[0014] Figure 3 is a schematic cross-sectional view showing a main part structure of a conventional mounting table.

[0015] Figure 4 is a schematic cross-sectional view showing a main part structure of the mounting table according to the second embodiment.

[0016] Figure 5AThis is a diagram showing an example of the cross-sectional shape of the elastic member according to the second embodiment.

[0017] Figure 5B This is a diagram showing another example of the cross-sectional shape of the elastic member according to the second embodiment.

[0018] Figure 6 This is a schematic cross-sectional view showing the main part structure of the mounting table according to the third embodiment.

[0019] Figure 7 This is a diagram showing an example of the cross-sectional shape of the electrostatic chuck according to the third embodiment. Detailed Embodiments

[0020] Hereinafter, embodiments of the mounting table and the plasma processing apparatus disclosed in the present application will be described in detail with reference to the drawings. In addition, the disclosed mounting table and plasma processing apparatus are not limited to the present embodiments.

[0021] In addition, in the plasma processing apparatus, deposits such as polymers are deposited on the structures around the substrate. Such deposits are lifted up due to electric field fluctuations or the like to become fine particles, which cause defects.

[0022] In the plasma processing apparatus, the base of the mounting table is cooled to a low temperature to suppress excessive temperature rise of the substrate and the mounting table due to heat input from the plasma. However, when such a groove is provided in the mounting table, the groove is cooled by the base and deposits are likely to be deposited in the groove.

[0023] Therefore, a technique for reducing the deposition of deposits in the groove is desired.

[0024] [First Embodiment]

[0025] [Structure of Plasma Processing Apparatus]

[0026] The embodiments will be described. First, the schematic structure of the plasma processing apparatus 10 according to the first embodiment will be described. Figure 1 This is a schematic cross-sectional view showing the schematic structure of the plasma processing apparatus 10 according to the first embodiment.

[0027] The plasma processing apparatus 10 is hermetically constructed and has a processing container 1 that is set to an electrical ground potential. The processing container 1 is cylindrical and is made of, for example, aluminum having an anodized film formed on its surface. The processing container 1 defines a processing space for generating plasma. A mounting table 2 is accommodated in the processing container 1, and the mounting table 2 supports a substrate W such as a semiconductor wafer, which is an object of plasma processing, horizontally.

[0028] The mounting table 2 is formed in a substantially cylindrical shape with the bottom surface facing the vertical direction. The mounting table 2 includes a base 3 and an electrostatic chuck 6.

[0029] The mounting table 2 has a first region 2a for mounting the substrate W and a second region 2b for mounting the edge ring 5. The first region 2a of the mounting table 2 is formed flat with the same size as the substrate W. The electrostatic chuck 6 is disposed on the upper surface of the first region 2a of the mounting table 2 and supports the electrostatic chuck 6. The second region 2b of the mounting table 2 is formed in an annular shape so as to surround the first region 2a. The edge ring 5 is disposed on the upper surface of the second region 2b of the mounting table 2 and supports the edge ring 5. The edge ring 5 is a circular member disposed around the substrate W. As the edge ring 5, for example, a focusing ring, an insulating ring can be cited. The mounting table 2 is divided into the first region 2a and the second region 2b by a groove 9 extending in an annular shape.

[0030] The base 3 is made of a conductive metal, for example, made of aluminum or the like. An anodic oxidation coating is formed on the surface of the base 3. The base 3 functions as a lower electrode. The base 3 is supported by the support table 4 made of an insulator. The support table 4 is provided at the bottom of the processing container 1.

[0031] The electrostatic chuck 6 is in a disk shape with a flat upper surface, and this upper surface becomes a mounting surface 6d for mounting the substrate W. The electrostatic chuck 6 has an electrode 6a and an insulator 6b. The electrode 6a is provided inside the insulator 6b. A DC power supply 12 is connected to the electrode 6a. The electrostatic chuck 6 is configured to adsorb the substrate W by Coulomb force by applying a DC voltage to the electrode 6a from the DC power supply 12. In addition, a heater 6c is provided inside the insulator 6b of the electrostatic chuck 6. The heater 6c is supplied with power by a power supply mechanism (not shown) to control the temperature of the substrate W.

[0032] The edge ring 5 is formed of, for example, single crystal silicon. The edge ring 5 is mounted on the second region 2b of the mounting table 2.

[0033] A power supply rod 50 is connected to the base 3. A first RF power supply 10a is connected to the power supply rod 50 via a first matcher 11a. In addition, a second RF power supply 10b is connected to the power supply rod 50 via a second matcher 11b. The first RF power supply 10a is a power supply for plasma generation. The base 3 is configured to be supplied with high-frequency power of a specified frequency from the first RF power supply 10a. The second RF power supply 10b is a power supply for ion introduction (bias). The base 3 is configured to supply high-frequency power of a specified frequency lower than the frequency of the first RF power supply 10a from the second RF power supply 10b to the base 3 of the mounting table 2.

[0034] A flow path 3a for the refrigerant to flow is formed inside the base 3. A refrigerant inlet pipe 3b is connected to one end of the flow path 3a, and a refrigerant outlet pipe 3c is connected to the other end of the flow path 3a. The flow path 3a is located below the substrate W and functions to absorb the heat of the substrate W.

[0035] The plasma processing apparatus 10 is configured to be able to control the temperature of the mounting stage 2 by circulating a refrigerant, such as cooling water, etc., in the flow path 3a. In addition, the plasma processing apparatus 10 can also be configured to be able to control the temperature by supplying a heat transfer gas to the back side of the substrate W and the edge ring 5. For example, a gas supply pipe for supplying a heat transfer gas (back gas), such as helium, etc., to the back side of the substrate W may be provided so as to penetrate the mounting stage 2 and the like. The gas supply pipe is connected to a gas supply source. With these structures, the substrate W adsorbed and held on the upper surface of the mounting stage 2 by the electrostatic chuck 6 is controlled to a predetermined temperature.

[0036] In addition, above the mounting stage 2, a shower head 16 is provided so as to face the mounting stage 2 in parallel. The shower head 16 has the function of an upper electrode. The shower head 16 and the mounting stage 2 function as a pair of electrodes (upper electrode and lower electrode).

[0037] The shower head 16 is provided in the top wall portion of the processing chamber 1. The shower head 16 includes a main body portion 16a and an upper top plate 16b forming an electrode plate. The shower head 16 is supported on the upper portion of the processing chamber 1 by an insulating member 95. The main body portion 16a is formed of a conductive material, for example, formed of aluminum having an anodized film formed on the surface. The main body portion 16a is configured to be able to support the upper top plate 16b in a detachable manner at the lower portion.

[0038] The main body portion 16a is provided with a gas diffusion chamber 16c inside. The main body portion 16a forms a plurality of gas flow holes 16d penetrating through the lower surface and communicating with the gas diffusion chamber 16c. In the upper top plate 16b, gas introduction holes 16e are provided so as to penetrate the upper top plate 16b in the thickness direction and overlap with the gas flow holes 16d. With such a structure, the processing gas supplied to the gas diffusion chamber 16c is supplied into the processing chamber 1 in a shower-like and dispersed manner via the gas flow holes 16d and the gas introduction holes 16e.

[0039] The main body portion 16a forms a gas introduction port 16g for introducing the processing gas into the gas diffusion chamber 16c. One end of a gas supply pipe 15a is connected to the gas introduction port 16g. The other end of the gas supply pipe 15a is connected to a processing gas supply source 15 that supplies the processing gas. The gas supply pipe 15a is provided with a mass flow controller (MFC) 15b and an on-off valve V2 in sequence from the upstream side. The processing gas supply source 15 supplies the processing gas for plasma etching to the gas supply pipe 15a. The processing gas is supplied to the gas diffusion chamber 16c via the gas supply pipe 15a. Then, the processing gas is supplied into the processing chamber 1 in a shower-like and dispersed manner from the gas diffusion chamber 16c via the gas flow holes 16d and the gas introduction holes 16e.

[0040] In the above-described case, the showerhead 16 serving as the upper electrode is electrically connected to a variable DC power source 72 via a low-pass filter (LPF) 71. The variable DC power source 72 is configured to be able to supply power and cut off power by turning on and off a switch 73. The current and voltage of the variable DC power source 72 and the on / off state of the switch 73 are controlled by a control unit 90 described later. When high-frequency power is applied to the stage 2 from the first RF power source 10a and the second RF power source 10b to generate plasma in the processing space, the switch 73 is turned on by the control unit 90 as needed, and a predetermined DC voltage is applied to the showerhead 16 serving as the upper electrode.

[0041] In addition, a cylindrical ground conductor 1a is provided so as to extend from the side wall of the processing chamber 1 to a position above the height position of the showerhead 16. The cylindrical ground conductor 1a has a top wall at the upper part.

[0042] An exhaust port 81 is formed at the bottom of the processing chamber 1. The exhaust port 81 is connected to an exhaust device 83 via an exhaust pipe 82. The exhaust device 83 has a vacuum pump. The exhaust device 83 is configured to be able to reduce the pressure in the processing chamber 1 to a predetermined vacuum level by operating the vacuum pump. In addition, a loading / unloading port 84 for the substrate W is provided on the side wall inside the processing chamber 1. A gate valve 85 for opening and closing the loading / unloading port 84 is provided at the loading / unloading port 84.

[0043] A deposition shield 86 is provided along the inner wall surface on the inner side of the side portion of the processing chamber 1. The deposition shield 86 prevents etching by-products (deposits) from adhering to the processing chamber 1. A conductive member (GND module) 89 connected to the ground potential in a controllable manner is provided at a height position substantially the same as that of the substrate W on the deposition shield 86, thereby preventing abnormal discharge. In addition, a deposition shield 87 extending along the stage 2 is provided at the lower end portion of the deposition shield 86. The deposition shields 86 and 87 are configured to be detachable.

[0044] The operation of the plasma processing apparatus 10 having the above-described structure is uniformly controlled by the control unit 90. The control unit 90 is provided with a process controller 91, a user interface 92, and a storage unit 93. The process controller 91 includes a CPU and controls each part of the plasma processing apparatus 10.

[0045] The user interface 92 includes a keyboard for a process manager to input commands for managing the plasma processing apparatus 10, a display for visually displaying the operating status of the plasma processing apparatus 10, and the like.

[0046] The process is stored in the storage unit 93. This process stores control programs (software), process condition data, etc. for implementing various processes executed by the plasma processing apparatus 10 under the control of the process controller 91. Then, as needed, any process is retrieved from the storage unit 93 according to an instruction from the user interface 92 or the like and the process controller 91 is made to execute it, so that under the control of the process controller 91, a desired process is performed in the plasma processing apparatus 10. In addition, the process such as the control program and the process condition data may be stored in an external hard disk or semiconductor memory. Further, the process such as the control program and the process condition data may be loaded at a specified position of the storage unit 93 in a state of being stored in a portable computer-readable storage medium such as a CD-ROM or a DVD.

[0047] [Structure of the mounting stage 2]

[0048] Next, with reference to Figure 2 the main part structure of the mounting stage 2 of the first embodiment will be described. Figure 2 FIG. is a schematic cross-sectional view showing the main part structure of the mounting stage 2 of the first embodiment.

[0049] The mounting stage 2 includes a base 3 and an electrostatic chuck 6. The mounting stage 2 has a first region 2a for mounting the substrate W and a second region 2b for mounting the edge ring 5. The electrostatic chuck 6 is disposed in the first region 2a on the base 3. The substrate W is mounted on the electrostatic chuck 6.

[0050] The base 3 is provided with a pedestal 7 in the second region 2b. The pedestal 7 is formed in an annular shape by, for example, silicon, quartz, aluminum, etc. The pedestal 7 is disposed so as to surround the first region 2a. The upper surface of the pedestal 7 is formed flat, and the edge ring 5 is mounted on this upper surface. The pedestal 7 supports the edge ring 5. In addition, the mounting stage 2 may not provided the pedestal 7 independently of the base 3, but the base 3 of the mounting stage 2 may function as the pedestal 7 for supporting the edge ring 5.

[0051] The base 3 is formed with a groove 9 between the first region 2a and the second region 2b. The upper surface of the mounting stage 2 is divided into the first region 2a and the second region 2b by the groove 9.

[0052] The base 3 is cooled by circulating a refrigerant in the flow path 3a, so that the base 3 becomes low temperature.

[0053] The electrostatic chuck 6 is provided with a heater 6c inside the insulator 6b. In addition, the heater 6c may be provided as one for the entire surface area of the mounting surface 6d, or may be provided individually for each region obtained by dividing the mounting surface 6d. That is, the heater 6c may be provided with a plurality of heaters individually for each region obtained by dividing the mounting surface 6d.

[0054] The plasma processing apparatus 10 cools the susceptor 3 while circulating the refrigerant in the flow path 3a, and supplies power to the heater 6c of the electrostatic chuck 6 to heat it, thereby controlling the temperature of the substrate W on the electrostatic chuck 6 to a prescribed temperature.

[0055] Here, when the susceptor 2 is provided with the groove 9, the groove 9 is cooled by the susceptor 3, and deposits such as polymers are likely to be deposited in the groove 9.

[0056] Then, on the susceptor 2, a shield that thermally separates the first region 2a and the second region 2b is provided in the groove 9. In the first embodiment, a side protection member 20 is provided as the shield in the groove 9, and the side protection member 20 protects the side surfaces of the electrostatic chuck 6 and the susceptor 3 facing the groove 9. The side protection member 20 is mainly made of a silicon-containing material (e.g., Si, SiO2 (quartz, etc.), SiC). In addition, the side protection member 20 can also be made of ceramics (e.g., Al2O3, AlN, Y2O3, etc.), or metals such as aluminum, titanium, and stainless steel whose surfaces have been subjected to insulation treatment (such as an oxide film, coating of an insulator, etc.).

[0057] The electrostatic chuck 6 is formed such that the outer diameter of the lower part is larger than the outer diameter of the upper part. A flange portion 6f that protrudes radially outward of the electrostatic chuck 6 is formed at the lower end of the electrostatic chuck 6.

[0058] The side protection member 20 is formed so as to cover the side surfaces of the electrostatic chuck 6 and the susceptor 3 along the inner side of the groove 9. The side protection member 20 is formed such that the inner diameter of the upper part is smaller than the inner diameter of the lower part with the inner diameter slightly larger than the diameter of the side surfaces of the electrostatic chuck 6 and the susceptor 3 located inside the groove 9. The side protection member 20 is clamped and held by the flange portion 6f of the electrostatic chuck 6.

[0059] [Function and Effect]

[0060] Next, the function and effect of the susceptor 2 of the first embodiment will be described.

[0061] In the plasma processing apparatus 10, when plasma processing such as plasma etching is performed, heat is input from the plasma to the substrate W, the edge ring 5, and the side protection member 20 placed on the susceptor 2. The temperature of the substrate W, the edge ring 5, and the side protection member 20 rises due to the heat input from the plasma. In addition, when the temperature of the substrate W and the edge ring 5 rises, radiant heat is input from the substrate W and the edge ring 5 to the side protection member 20. In addition, when heating is performed using the heater 6c, heat is input from the electrostatic chuck 6 to the side protection member 20. As a result, the temperature of the side protection member 20 rises and it is difficult for deposits to adhere.

[0062] Here, as a comparative example, an example of the structure of a conventional susceptor 2 is shown. Figure 3is a schematic cross-sectional view showing the main part structure of the conventional stage 2. The conventional stage 2 is configured such that a groove 9 is provided between a first region 2a for placing the substrate W and a second region 2b for placing the edge ring 5, and the temperature difference can be increased. In the conventional stage 2, the groove 9 is a space without any components arranged therein. In this way, when the groove 9 is provided in the stage 2, the surface of the groove 9 is cooled by the base 3, and deposits 9a such as polymers are deposited in the groove 9. Such deposits 9a are lifted up to become fine particles due to electric field fluctuations or the like, and become the cause of defects. Conventionally, in the plasma processing apparatus 10, the mainstream method is to remove the deposits deposited on the structures around the substrate by plasma processing cleaning. However, the cleaning using plasma not only removes the deposits, but may also cause damage to normal fittings due to plasma.

[0063] In addition, as Figure 2 shown, the stage 2 of the first embodiment is provided with a side protection member 20 in the groove 9. The side surface of the base 3 exposed from the groove 9 becomes the same temperature as the refrigerant temperature. In the stage 2 of the first embodiment, the side surface of the base 3 is covered by the side protection member 20 whose temperature is higher than the temperature of the side surface of the base 3. That is, until now, although located close to the substrate W, the side surface of the base 3 which is kept at a low temperature and where deposits 9a are likely to deposit is covered by the side protection member 20, and instead, the side protection member 20 after being heated is exposed. Since the temperature of the side protection member 20 is higher than the temperature of the exposed base 3, deposition of deposits can be suppressed as compared with the prior art. In this way, in the stage 2 of the first embodiment, by providing the side protection member 20 in the groove 9, deposition of deposits in the groove 9 can be reduced. As a result, in the plasma processing apparatus 10 of the first embodiment, the deposits in the groove 9 can be removed in a manner such that the time or degree of cleaning using plasma is shorter or weaker than in the prior art, and damage to the fittings caused by plasma can be reduced. In addition, in the stage 2 of the first embodiment, when deposits are deposited on the side protection member 20, the deposits can be removed by replacing the side protection member 20.

[0064] In addition, the side protection member 20 of the first embodiment is formed such that its inner diameter is slightly larger than the diameter of the side surfaces of the electrostatic chuck 6 and the base 3 located inside the groove 9, and a slight gap is provided between the side protection member 20 and the side surfaces of the electrostatic chuck 6 and the base 3 located inside the groove 9. Thus, the mounting table 2 of the first embodiment can suppress heat transfer between the side protection member 20 and the base 3 to a relatively small extent. As a result, the mounting table 2 of the first embodiment can efficiently set the temperature of the side protection member 20 higher than that of the base 3, and can reduce the deposition of deposits. In addition, since there is a gap between the side protection member 20 and the electrostatic chuck 6 and the base 3, even when there is a difference in thermal expansion between the side protection member 20 and the electrostatic chuck 6 and the base 3, it is possible to suppress the side protection member 20 from cracking or the like.

[0065] As described above, the mounting table 2 of the first embodiment includes an electrostatic chuck 6, a base 3, and a shield (side protection member 20). The electrostatic chuck 6 adsorbs the substrate W. The base 3 is divided by a groove 9 extending in a ring shape into a first region 2a that supports the electrostatic chuck 6 and a second region 2b that supports the edge ring 5 disposed around the substrate W. The shield is provided in the groove 9 to thermally separate the first region 2a from the second region 2b. Thus, the mounting table 2 can reduce the deposition of deposits in the groove 9.

[0066] In addition, the base 3 is provided with a flow path 3a through which a refrigerant flows. Thus, the mounting table 2 can cool the base 3 by causing the refrigerant to flow in the flow path 3a, and thereby can control the temperature of the substrate W.

[0067] In addition, the mounting table 2 is provided with a heater 6c in the first region 2a. Thus, the mounting table 2 can control the temperature of the substrate W by heating with the heater 6c.

[0068] In addition, the shield (side protection member 20) is formed in a cylindrical shape to protect the side surfaces of the electrostatic chuck 6 and the base 3 facing the groove 9. Thus, the mounting table 2 can reduce the deposition of deposits on the side surfaces of the electrostatic chuck 6 and the base 3 facing the groove 9.

[0069] [Second Embodiment]

[0070] Next, the second embodiment will be described. The plasma processing apparatus 10 of the second embodiment has the same structure as the Figure 1 plasma processing apparatus 10 of the first embodiment shown, and thus the description thereof will be omitted.

[0071] Figure 4 is a schematic cross-sectional view showing the main part structure of the mounting table 2 of the second embodiment. The mounting table 2 of the second embodiment is the same as the Figure 2The structure of the mounting table 2 of the first embodiment shown is partially the same, so the same reference numerals are given to the same parts and the description thereof is omitted, and mainly the different parts will be described.

[0072] In the mounting table 2 of the second embodiment, an elastic member 21 is provided as a shield in the groove 9. Examples of the elastic member 21 include rubber and the like. The elastic member 21 is formed in a long strip shape or in a ring shape. The elastic member 21 is mounted on the mounting table 2 along the groove 9. In the mounting table 2 of the second embodiment, the elastic member 21 is tightened so as to cover the side surfaces of the electrostatic chuck 6 and the base 3.

[0073] In the case where the side surface of the base 3 is covered with the strip-shaped elastic member 21 in this way, the contact area between the elastic member 21 and the low-temperature base 3 is large, and the temperature of the elastic member 21 is likely to drop.

[0074] Therefore, in the mounting table 2 of the second embodiment, the elastic member 21 is formed into a shape with a smaller contact area with the low-temperature base 3.

[0075] Figure 5A FIG. is a diagram showing an example of the cross-sectional shape of the elastic member 21 of the second embodiment. On the Figure 5A left side, the cross-sectional shape of the elastic member 21 is shown. The elastic member 21 is formed into a cross-sectional shape having a protrusion 21a protruding inwardly at the upper part. The elastic member 21 is formed such that its inner diameter is approximately the same as or slightly smaller than the diameter of the groove 9. For example, the elastic member 21 is formed such that its inner diameter is smaller than the diameter of the groove 9 by a specified amount (for example, several cm). On the Figure 5A right side, the state where the elastic member 21 is mounted on the mounting table 2 is shown. For example, the elastic member 21 is mounted on the mounting table 2 along the groove 9 in a shape in which the elastic member 21 is stretched. In the Figure 5A case where the elastic member 21 shown is mounted on the mounting table 2, since the protrusion 21a is provided on the upper side of the elastic member 21 that contacts the electrostatic chuck 6, the electrostatic chuck 6 can be tightened. In addition, the inner diameter of the lower side of the elastic member 21 that contacts the base 3 is larger than the inner diameter at the position of the protrusion 21a. Therefore, under the action of the restoring force of the rubber, the lower end portion remains in contact with the base 3, and a non-contact region that does not contact the base 3 is formed below the protrusion 21a. Thereby, the contact area between the elastic member 21 and the base 3 can be reduced. That is to say, Figure 5A the contact area between the elastic member 21 shown and the base 3 is small, and the contact thermal resistance between the elastic member 21 and the base 3 is large. Therefore, the elastic member 21 is not easily affected by the temperature of the base 3.

[0076] Figure 5B FIG. is a diagram showing another example of the cross-sectional shape of the elastic member 21 of the second embodiment. In theFigure 5B The left side of Figure 5B shows the cross-sectional shape of the elastic member 21. The elastic member 21 is provided with a cross-sectional shape in which protrusions 21c and 21d protruding inward are provided at both upper and lower ends. The width of the lower protrusion 21d in the vertical direction is formed to be smaller than the width of the upper protrusion 21c in the vertical direction. The elastic member 21 is formed to have an inner diameter that is about the same as or slightly smaller than the diameter of the groove 9. For example, the elastic member 21 is formed to have an inner diameter that is smaller than the diameter of the groove 9 by a specified amount (for example, several cm). Figure 5B The right side of Figure 5B shows the state in which the elastic member 21 is mounted on the mounting table 2. For example, the elastic member 21 is mounted on the mounting table 2 along the groove 9 in a shape that stretches the elastic member 21. Figure 5B In the case where the elastic member 21 shown in Figure 5B is mounted on the mounting table 2, since the protrusions 21c and 21d are provided at the upper and lower ends of the elastic member 21, it is possible to tighten the electrostatic chuck 6 and the base 3 at the upper and lower ends. In addition, since the inner diameter of the middle part between the protrusion 21c and the protrusion 21d of the elastic member 21 is large, a non-contact area that does not contact the base 3 can be formed in the middle part. In addition, the protrusion 21d of the elastic member 21 that contacts the base 3 is formed to be smaller than the protrusion 21c. Thereby, the contact area between the elastic member 21 and the base 3 can be reduced. That is, Figure 5B The contact area between the elastic member 21 shown in Figure 5B and the base 3 is small, and the contact thermal resistance between the elastic member 21 and the base 3 becomes large, so the elastic member 21 is not easily affected by the temperature of the base 3.

[0077] The elastic member 21 receives heat from the electrostatic chuck 6 and the surrounding structures whose temperature rises due to heat input from the plasma, and the temperature rises. In addition, although the elastic member 21 also contacts the low-temperature base 3, by providing the protrusions 21a, 21c, and 21d, the contact area between the elastic member 21 and the base 3 can be reduced. Thereby, the temperature of the elastic member 21 rises and the adhesion of deposits is suppressed, and the deposition of deposits in the groove 9 can be reduced. In addition, in the mounting table 2 of the second embodiment, when deposits are deposited on the elastic member 21, the deposits can be removed by replacing the elastic member 21.

[0078] As described above, in the mounting table 2 of the second embodiment, the shielding member is the elastic member 21 formed in a ring shape, and this shielding member protects the electrostatic chuck 6 and the side surfaces of the base 3 facing the groove 9. Thereby, the mounting table 2 can reduce the deposition of deposits on the side surfaces of the electrostatic chuck 6 and the base 3 facing the groove 9.

[0079] In addition, the elastic member 21 is provided with first protrusions (protrusions 21a and 21c) protruding toward the inner side of the ring shape, and the first protrusions are used to contact the electrostatic chuck 6. In addition, the elastic member 21 is provided with second protrusions (protrusions 21d) protruding toward the inner side of the ring shape, and the second protrusions are used to contact the base 3. In addition, the elastic member 21 is formed such that the width in the vertical direction of the second protrusion (protrusion 21d) is smaller than the width in the vertical direction of the first protrusion (protrusion 21c). Thereby, the contact area between the elastic member 21 and the base 3 can be reduced, and the elastic member 21 can be made less susceptible to the temperature of the base 3.

[0080] [Third Embodiment]

[0081] Next, the third embodiment will be described. Since the plasma processing apparatus 10 of the third embodiment has the same structure as the Figure 1 plasma processing apparatus 10 of the first embodiment shown, the description thereof will be omitted.

[0082] Figure 6 is a schematic cross-sectional view showing the main part structure of the mounting table 2 of the third embodiment. The mounting table 2 of the third embodiment has a structure partially the same as the Figure 2 mounting table 2 of the first embodiment shown and the Figure 4 mounting table 2 of the second embodiment shown. Therefore, the same reference numerals are assigned to the same parts and the description thereof is omitted, and mainly the different parts will be described.

[0083] In the mounting table 2 of the third embodiment, the outer peripheral portion of the electrostatic chuck 6 is extended, and the outer peripheral portion of the electrostatic chuck 6 is provided at the lower part of the groove 9 so as to cover the side surface of the base 3. The mounting table 2 of the third embodiment is provided with an extended portion 6g obtained by extending the outer peripheral portion of the electrostatic chuck 6 to the side surface of the base 3 as a shielding member in the groove 9. Since the electrostatic chuck 6 is heated by the heater 6c, the temperature of the outer peripheral portion is not likely to drop. The side surface of the base 3 is covered by the extended portion 6g so as not to be exposed, whereby the deposition of deposits in the groove 9 can be reduced. In addition, the extended portion 6g can also be sealed with the base 3 by disposing a seal, an O-ring, etc. on the lower surface. Thereby, the deposition of deposits between the extended portion 6g and the base 3 can be suppressed.

[0084] The electrostatic chuck 6 may also be provided with a heater in the extended portion 6g extended to the side surface of the base 3. Figure 7FIG. is an example of a cross-sectional shape of the electrostatic chuck 6 according to the third embodiment. The electrostatic chuck 6 is provided with a heater 6h in an extended portion 6g that extends to the side surface of the base 3 at the outer peripheral portion. Electric power is supplied to the heater 6h independently from a DC power source 12 or a DC power source (not shown). As a result, the temperature of the extended portion 6g of the electrostatic chuck 6 corresponding to the side surface of the base 3 rises, suppressing the adhesion of deposits, and the deposition of deposits in the groove 9 can be reduced.

[0085] As described above, in the mounting table 2 according to the third embodiment, the shield (extended portion 6g) is formed by extending the electrostatic chuck 6 to the side surface of the base 3 located in the groove 9. As a result, the mounting table 2 can reduce the deposition of deposits on the side surface of the base 3 facing the groove 9.

[0086] In addition, the shield (extended portion 6g) is provided with a heater 6h in the extended portion that extends to the side surface of the base 3 located in the groove 9. As a result, it is less susceptible to the temperature of the base 3.

[0087] The embodiments have been described above, but it should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. In fact, the above-described embodiments can be specifically implemented in various forms. In addition, the above-described embodiments can also be omitted, replaced, and changed in various forms without departing from the scope of the claims and their gist.

[0088] For example, in each of the above-described embodiments, the side protection member 20, the elastic member 21, and the surface of the extended portion 6g can also be colored black to easily absorb radiant heat from the edge ring 5.

[0089] In addition, in each of the above-described embodiments, the case where the temperature of the edge ring 5 rises due to heat input from the plasma and radiant heat is input from the edge ring 5 to the side protection member 20, the elastic member 21, and the extended portion 6g has been described as an example. However, the disclosed technology is not limited to this. A contact portion that contacts the edge ring 5 can also be provided locally or integrally in the circumferential direction of the side protection member 20, the elastic member 21, and the extended portion 6g, and the temperature can be raised by heat transfer from the edge ring 5 through the contact portion. For example, contact portions that contact the edge ring 5 can also be provided at regular intervals (e.g., 30°) at intervals in the circumferential direction of the side protection member 20, the elastic member 21, and the extended portion 6g, and heat can be transferred from the edge ring 5.

[0090] In addition, in each of the above-described embodiments, the case where the electrostatic chuck 6 is provided with the heater 6c has been described as an example. However, the disclosed technology is not limited to this. The heater 6c may not be provided in the electrostatic chuck 6.

[0091] In addition, it should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. In fact, the above embodiments can be specifically realized in various forms. Additionally, the above embodiments can also be omitted, replaced, and changed in various forms without departing from the appended claims and their gist.

Claims

1. A stage for placing a substrate, wherein, the stage has: an electrostatic chuck for adsorbing the substrate; a base table divided by a circumferentially extending groove into a first region for supporting the electrostatic chuck and a second region for supporting an edge ring disposed around the substrate; and a shield provided in the groove, the shield thermally separating the first region from the second region; and a circular base provided in the second region and supporting the edge ring, wherein the shield is an elastic member formed in a ring shape, protecting the electrostatic chuck and the side surface of the base table facing the groove, the elastic member is provided with a first protrusion protruding toward the inner side of the ring, and the elastic member contacts the electrostatic chuck with the first protrusion without contacting the base table, the elastic member is provided with a second protrusion protruding toward the inner side of the ring, and the elastic member contacts the base table with the second protrusion without contacting the electrostatic chuck, the first protrusion and the second protrusion are separated from each other in the vertical direction, wherein the groove is formed between the electrostatic chuck and the edge ring and between the base table and the circular base.

2. The stage according to claim 1, wherein, the base table is provided with a flow path for refrigerant to flow through.

3. The stage according to claim 1 or 2, wherein, the first region is provided with a heater.

4. The stage according to claim 1, wherein, the elastic member is formed such that the width in the up-down direction of the second protrusion is smaller than the width in the up-down direction of the first protrusion.

5. A plasma processing apparatus, wherein, the plasma processing apparatus has the stage according to any one of claims 1 to 4.

Images