Plasma processing apparatus

Abstract

The present invention relates to a plasma processing apparatus. There is provided a plasma processing apparatus capable of shortening the time until process stabilization when replacing a consumable member. The plasma processing apparatus includes: a mounting table for mounting a substrate; a chamber for housing the mounting table; a gas supply unit for supplying a processing gas into the chamber; a plasma generation unit for generating plasma in the chamber; a consumable member disposed in a space where the plasma is generated and consumed by the plasma; and a control unit. The consumable member has: a base member formed of a material containing an oxygen element; and a cover member formed of a material not containing an oxygen element, and at least a part of a surface of the base member exposed to the space where the plasma is generated is covered by the cover member.

Description

Technical Field

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

[0002] There is known a plasma processing apparatus that supplies a processing gas into a chamber, generates plasma from the processing gas, and performs a desired process on a substrate. When performing plasma processing, since components in the chamber are consumed and reaction by-products accumulate, time is required before stabilization.

[0003] Patent Document 1 discloses the following plasma processing apparatus: A vacuum processing container includes a side wall member, a lid member, and a dielectric plate, and a film containing yttrium is formed on the inner surface of the side wall member and the outer peripheral portion of the surface of the dielectric plate on the side wall member side.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2007-243020 Summary of the Invention

[0005] Problems to be Solved by the Invention

[0006] In one aspect, the present disclosure provides a plasma processing apparatus capable of shortening the time until process stabilization when replacing a consumable component.

[0007] Solutions for Solving the Problems

[0008] To solve the above problems, according to one aspect of the technical solution, there is provided a plasma processing apparatus including: a stage for placing a substrate; a chamber for accommodating the stage; a gas supply unit for supplying a processing gas into the chamber; a plasma generation unit for generating plasma in the chamber; a consumable component disposed in the space where the plasma is generated and consumed by the plasma; and a control unit, the consumable component having: a base member formed of a material containing an oxygen element; and a lid member formed of a material not containing an oxygen element, at least a part of the surface of the base member exposed to the space where the plasma is generated being covered by the lid member.

[0009] Effects of the Invention

[0010] According to one aspect, it is possible to provide a plasma processing apparatus capable of shortening the time until process stabilization when replacing a consumable component. Brief Description of the Drawings

[0011] Figure 1 It is a cross-sectional schematic view showing an example of the plasma processing apparatus of the present embodiment.

[0012] Figure 2It is a partially enlarged view of the plasma processing apparatus of the present embodiment.

[0013] Figure 3 It is a partially enlarged view of the plasma processing apparatus of the reference example.

[0014] Figure 4 It is an example of a top view of the cover ring.

[0015] Figure 5 It is a partially enlarged view of the plasma processing apparatus of other embodiments. Detailed Embodiments

[0016] Hereinafter, the modes for implementing the present disclosure will be described with reference to the drawings. In each drawing, the same reference numerals are assigned to the same structural parts, and repeated descriptions may be omitted sometimes.

[0017] Use Figure 1 The plasma processing apparatus 1 of the present embodiment will be described. Figure 1 It is a cross-sectional schematic view showing an example of the plasma processing apparatus 1 of the present embodiment. In the following description, the plasma processing apparatus 1 is described, for example, as a plasma etching apparatus for etching an insulating film (SiO2 film, SiN film) formed on a substrate W.

[0018] The plasma processing apparatus 1 includes a chamber 10. The chamber 10 provides an internal space 10s therein. The chamber 10 includes a chamber body 12. The chamber body 12 has a substantially cylindrical shape. The chamber body 12 is formed of, for example, aluminum. A corrosion-resistant film is provided on the inner wall surface of the chamber body 12. This film may also be a ceramic such as alumina or yttria.

[0019] A passage 12p is formed in the side wall of the chamber body 12. The substrate W is transported between the internal space 10s and the outside of the chamber 10 via the passage 12p. The passage 12p is opened and closed by a gate valve 12g provided along the side wall of the chamber body 12.

[0020] A support portion 13 is provided on the bottom of the chamber body 12. The support portion 13 is formed of an insulating material. The support portion 13 has a substantially cylindrical shape. The support portion 13 extends upward from the bottom of the chamber body 12 in the internal space 10s. The support portion 13 has a support table 14 at the upper part. The support table 14 is configured to support the substrate W in the internal space 10s.

[0021] The support table 14 has a lower electrode 18 and an electrostatic chuck 20. The support table 14 may also have an electrode plate 16. The electrode plate 16 is formed of a conductor such as aluminum and has a substantially disc shape. The lower electrode 18 is provided on the electrode plate 16. The lower electrode 18 is formed of a conductor such as aluminum and has a substantially disc shape. The lower electrode 18 is electrically connected to the electrode plate 16.

[0022] The electrostatic chuck 20 is provided on the lower electrode 18. A substrate W is placed on the upper surface of the electrostatic chuck 20. The electrostatic chuck 20 has a main body and an electrode. The main body of the electrostatic chuck 20 is substantially disk-shaped and is formed of a dielectric. The electrode of the electrostatic chuck 20 is a film-like electrode provided inside the main body of the electrostatic chuck 20. The electrode of the electrostatic chuck 20 is connected to a DC power supply 20p via a switch 20s. When a voltage from the DC power supply 20p is applied to the electrode of the electrostatic chuck 20, an electrostatic attraction is generated between the electrostatic chuck 20 and the substrate W. Using this electrostatic attraction, the substrate W is held on the electrostatic chuck 20.

[0023] An edge ring 25 is arranged on the peripheral portion of the lower electrode 18 so as to surround the edge of the substrate W. The edge ring 25 improves the in-plane uniformity of the plasma treatment for the substrate W. The edge ring 25 can be formed of silicon, silicon carbide, quartz, or the like.

[0024] In addition, a cover ring 26 is provided on the outer peripheral side of the edge ring 25 so as to surround the edge ring 25. The cover ring 26 is formed of an insulator such as quartz, for example. The cover ring 26 protects the upper surface of the support portion 13 and the side wall of the lower electrode 18 from plasma. The cover ring 26 is configured to be replaceable.

[0025] A flow path 18f is provided inside the lower electrode 18. A heat exchange medium (e.g., refrigerant) is supplied to the flow path 18f from a cooler unit (not shown) provided outside the chamber 10 via a pipe 22a. The heat exchange medium supplied to the flow path 18f returns to the cooler unit 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 the heat exchange between the heat exchange medium and the lower electrode 18.

[0026] A gas supply line 24 is provided in the plasma processing apparatus 1. The gas supply line 24 supplies a heat transfer gas (e.g., He gas) from a heat transfer gas supply mechanism between the upper surface of the electrostatic chuck 20 and the back surface of the substrate W.

[0027] The plasma processing apparatus 1 further includes an upper electrode 30. The upper electrode 30 is provided above the support table 14. The upper electrode 30 is supported on the upper part of the chamber main body 12 by members 32, 33. The members 32, 33 are formed of a material having insulating properties. The upper electrode 30 and the members 32, 33 close the upper opening of the chamber main body 12. The member 33 is provided on the outer peripheral side of the top plate 34 so as to surround the top plate 34. The member 33 is exposed to the internal space 10s and is formed of an insulator such as quartz, for example. It is configured such that the member 32 and the member 33 are provided as different components, so that the member 33 consumed by plasma can be replaced.

[0028] The upper electrode 30 may include a top plate 34 and a support body 36. The lower surface of the top plate 34 is the lower surface on the inner space 10s side, which divides and forms the inner space 10s. The top plate 34 may be formed of a low-resistance conductor or semiconductor that generates less Joule heat. The top plate 34 has a plurality of gas ejection holes 34a penetrating therethrough in its plate thickness direction.

[0029] The support body 36 supports the top plate 34 in a detachable manner. The support body 36 is formed of a conductive material such as aluminum. A gas diffusion chamber 36a is provided inside the support body 36. The support body 36 has a plurality of gas holes 36b extending downward from the gas diffusion chamber 36a. The plurality of gas holes 36b communicate with the plurality of gas ejection holes 34a respectively. A gas inlet 36c is formed in the support body 36. The gas inlet 36c is connected to the gas diffusion chamber 36a. A gas supply pipe 38 is connected to the gas inlet 36c.

[0030] A valve group 42, a flow controller group 44, and a gas source group 40 are connected to the gas supply pipe 38. The gas source group 40, the valve group 42, and the flow controller group 44 constitute a gas supply unit. The gas source group 40 includes a plurality of gas sources. The valve group 42 includes a plurality of on-off valves. The flow controller group 44 includes a plurality of flow controllers. The plurality of flow controllers in the flow controller group 44 are respectively mass flow controllers or pressure-controlled flow controllers. The plurality of gas sources in the gas source group 40 are respectively connected to the gas supply pipe 38 through the corresponding on-off valves in the valve group 42 and the corresponding flow controllers in the flow controller group 44.

[0031] In the plasma processing apparatus 1, a shield 46 is detachably provided along the inner wall surface of the chamber body 12 and the outer periphery of the support portion 13. Thus, the shield 46 is configured to be replaceable. The shield 46 prevents reaction by-products from adhering to the chamber body 12. The shield 46 is constituted, for example, by forming a corrosion-resistant film on the surface (inner peripheral surface) of a base material formed of aluminum. The corrosion-resistant film may be formed of ceramics such as acid-resistant aluminum or yttrium oxide.

[0032] A partition plate 48 is provided between the support portion 13 and the side wall of the chamber body 12. The partition plate 48 is constituted, for example, by forming a corrosion-resistant film (such as a yttrium oxide film) on the surface of a base material formed of aluminum. A plurality of through holes are formed in the partition plate 48. An exhaust port 12e is provided below the partition plate 48 and at the bottom of the chamber body 12. The exhaust port 12e is connected to an exhaust device 50 via an exhaust pipe 52. The exhaust device 50 includes a vacuum pump such as a pressure regulating valve and a turbo molecular pump.

[0033] The plasma processing apparatus 1 includes a first high-frequency power source 62 and a second high-frequency power source 64. The first high-frequency power source 62 is a power source that generates first high-frequency power. The first high-frequency power has a frequency suitable for plasma generation. The frequency of the first high-frequency power is, for example, a frequency in the range of 27 MHz to 100 MHz. The first high-frequency power source 62 is connected to the lower electrode 18 via a matcher 66 and an electrode plate 16. The matcher 66 has a circuit for matching the output impedance of the first high-frequency power source 62 with the impedance on the load side (the lower electrode 18 side). In addition, the first high-frequency power source 62 may also be connected to the upper electrode 30 via the matcher 66. The first high-frequency power source 62 constitutes an example of a plasma generation unit.

[0034] The second high-frequency power source 64 is a power source that generates second high-frequency power. The second high-frequency power has a frequency lower than that of the first high-frequency power. When the second high-frequency power is used together with the first high-frequency power, the second high-frequency power is used as high-frequency power for bias voltage for introducing ions into the substrate W. The frequency of the second high-frequency power is, for example, a frequency in the range of 400 kHz to 13.56 MHz. The second high-frequency power source 64 is connected to the lower electrode 18 via a matcher 68 and an electrode plate 16. The matcher 68 has a circuit for matching the output impedance of the second high-frequency power source 64 with the impedance on the load side (the lower electrode 18 side).

[0035] In addition, the first high-frequency power may not be used and the second high-frequency power may be used, that is, plasma may be generated using only a single high-frequency power. In this case, the frequency of the second high-frequency power may also be a frequency greater than 13.56 MHz, for example, 40 MHz. The plasma processing apparatus 1 may not include the first high-frequency power source 62 and the matcher 66. The second high-frequency power source 64 constitutes an example of a plasma generation unit.

[0036] In the plasma processing apparatus 1, gas is supplied from the gas supply unit to the internal space 10s to generate plasma. In addition, by supplying the first high-frequency power and / or the second high-frequency power, a high-frequency electric field is generated between the upper electrode 30 and the lower electrode 18. The generated high-frequency electric field generates plasma.

[0037] The plasma processing apparatus 1 includes a power source 70. The power source 70 is connected to the upper electrode 30. The power source 70 applies a voltage for introducing positive ions existing in the internal space 10s into the top plate 34 to the upper electrode 30.

[0038] 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, an input / output interface for signals, etc. The control unit 80 controls each part of the plasma processing apparatus 1. For an operator to use the input device to manage the plasma processing apparatus 1, input operations of commands can be performed in the control unit 80. In addition, the control unit 80 can visually display the operating status of the plasma processing apparatus 1 using the display device. Moreover, a control program and process data are stored in the storage unit. To execute various processes in the plasma processing apparatus 1, the control program is executed by the processor. The processor executes the control program and controls each part of the plasma processing apparatus 1 according to the process data.

[0039] An example of the operation of the plasma processing apparatus 1 will be described. An insulating film (such as a SiO2 film, a SiN film, etc.) as an etching target film is formed on the substrate W. In addition, a mask having an opening is formed on the insulating film.

[0040] The control unit 80 controls the gas source group 40, the valve group 42, and the flow controller group 44 to supply an etching gas and argon from the gas hole 36b to the internal space 10s. As the etching gas, fluorocarbons, hydrofluorocarbons, etc. are used. Fluorocarbons are, for example, CF4, C4F6, C4F8, and hydrofluorocarbons are, for example, CHF3, CH2F2. In addition, the control unit 80 controls the first high-frequency power supply 62 to apply a first high-frequency power for generating plasma to the lower electrode 18. In addition, the control unit 80 controls the second high-frequency power supply 64 to apply a second high-frequency power for introducing ions to the substrate W to the lower electrode 18.

[0041] Thereby, the insulating film is etched through the mask using the plasma generated in the internal space 10s. In addition, due to the plasma generated in the internal space 10s, the edge ring 25, the cover ring 26, the member 33, the shield 46, etc. are consumed.

[0042] In addition, when etching the insulating film, reaction by-products are generated. As reaction by-products, for example, fluorocarbons, hydrocarbons, etc. are generated. The reaction by-products are exhausted from the internal space 10s by the exhaust device 50. In addition, a part of the reaction by-products adheres to the edge ring 25, the cover ring 26, the member 33, the shield 46, etc.

[0043] Next, use Figure 2 The plasma processing apparatus 1 of the present embodiment will be further described. Figure 2 FIG. is an example of a partial enlarged view of the plasma processing apparatus 1 of the present embodiment. Figure 2 (a) shows the initial state immediately after replacing the cover ring 26 due to maintenance or the like. Figure 2The state shown in (b) indicates that the cover ring 26 has been consumed after a certain period of time and reaction by-products 200 are attached.

[0044] As Figure 1 and Figure 2 shown, the substrate W is placed on the support table 14, specifically, on the electrostatic chuck 20 provided on the lower electrode 18. The edge ring 25 that improves the in-plane uniformity of the plasma treatment for the substrate W is arranged on the lower electrode 18 so as to surround the edge of the substrate W. The cover ring 26 that protects the upper surface of the support portion 13 (refer to Figure 1 ) and the side wall of the lower electrode 18 from the plasma is arranged so as to surround the edge ring 25 on the outer peripheral side of the edge ring 25.

[0045] In addition, in Figure 2 , the region where plasma is generated is schematically shown by a dotted-line frame. When the insulating film of the substrate W is etched by plasma treatment, reaction by-products 200 are generated. A part of the reaction by-products 200 adheres to the cover ring 26 and the like. Here, the region 301 on the side closer to the plasma generation region is a region where the etching rate of the reaction by-products 200 adhering to the surface of the cover ring 26 is higher than the deposition rate of the reaction by-products 200. On the surface of the cover ring 26 in the region 301, the adhering reaction by-products 200 are etched by the plasma, maintaining the state where the surface of the cover ring 26 is exposed. In addition, the region 302 outside the region 301 is a region where the etching rate of the reaction by-products 200 adhering to the surface of the cover ring 26 is lower than the deposition rate of the reaction by-products 200. As Figure 2 shown in (b), on the surface of the cover ring 26 in the region 302, the surface of the cover ring 26 is covered with the adhering reaction by-products 200.

[0046] As Figure 2 shown in (a), the cover ring 26 has a base member 110 and a cover member 120.

[0047] The base member 110 is a circular member formed of a material (for example, SiO2) containing an element that affects the process characteristics, specifically, oxygen element (O). In Figure 2 the example of (a), the base member 110 has: an upper surface 111 that faces the plasma generation region; an inclined surface 112 that is away from the plasma generation region with respect to the upper surface 111; and an outer side surface 113 that is away from the inclined surface 112 with respect to the inclined surface 112.

[0048] The lid member 120 is formed of a material that does not contain elements that affect process characteristics, specifically oxygen element (O). In addition, the lid member 120 is formed of the same material as the reaction by-products generated by the process of the plasma processing apparatus 1. Here, in a process of using a fluorocarbon-based gas (CF4, C4F6, C4F8, etc.) as an etching gas and generating a fluorocarbon as a reaction by-product, the lid member 120 is formed of a material containing carbon element (C) and fluorine element (F). In addition, as long as the reaction by-products and the lid member 120 are composed of the same elements, the compounds do not have to be the same. In the present embodiment, as the material of the lid member 120, fluororesins such as PTFE (polytetrafluoroethylene) and PCTFE (polychlorotrifluoroethylene) can be used.

[0049] In addition, it is preferable that the lid member 120 is made of a material that is consumed more by plasma than the base member 110 (for example, SiO2). In other words, it is preferable that the lid member 120 is made of a material with lower plasma resistance than the base member 110.

[0050] The lid member 120 is formed to cover the inclined surface 112 and the outer side surface 113. In addition, the lid member 120 may be formed to cover a part of the upper surface 111 and expose a part. In addition, the lid member 120 may be formed to cover a part of the inclined surface 112 and expose a part.

[0051] In addition, the lid member 120 may be formed as a part and assembled with the base member 110 to form the lid ring 26. In addition, the lid member 120 may be formed as a coating film by applying a slurry-like fluororesin to the base member 110 and curing it. In addition, the formation method of the lid member 120 is not limited to this.

[0052] Here, while comparing with the plasma processing apparatus of the reference example, the plasma processing apparatus 1 of the present embodiment will be further described.

[0053] Figure 3 is an example of a partial enlarged view of the plasma processing apparatus of the reference example. Figure 3 (a) of shows the initial state just after replacing the lid ring 26C due to maintenance or the like. Figure 3 (b) of shows the state where the lid ring 26C is consumed and the reaction by-products 200 are attached after a period of time.

[0054] Compared with the plasma processing apparatus 1 of the present embodiment (refer to Figure 2 ), the lid ring 26C of the plasma processing apparatus of the reference example (refer to Figure 3 ) is different. The other structures are the same, and repeated descriptions are omitted. As Figure 3As shown in (a), the cover ring 26C is different from the cover ring 26 in that the cover member 120 is not provided. That is, the cover ring 26C is an annular member formed of a material containing oxygen (O) (for example, SiO2). In Figure 3 In the example of (a), the cover ring 26C has: an upper surface 111 facing the plasma generation region; an inclined surface 112 away from the plasma generation region with respect to the upper surface 111; and an outer side surface 113 away from the inclined surface 112 with respect to the inclined surface 112.

[0055] In the initial state of the plasma processing apparatus of the reference example, as Figure 3 shown in (a), the upper surface 111, the inclined surface 112, and the outer side surface 113 are exposed to the internal space 10s. Therefore, when an etching process is applied to the substrate W, the upper surface 111 and the inclined surface 112 of the cover ring 26C exposed to the plasma are consumed, and oxygen radicals (O ＊ ) are generated from the cover ring 26C. In other words, in the initial state, oxygen radicals (O ＊ ) are generated from the surface (upper surface 111) of the cover ring 26C in the region 301 and the surface (inclined surface 112) of the cover ring 26C in the region 302. The oxygen radicals (O ＊ ) generated when the cover ring 26C is consumed affect the etching characteristics of the substrate W.

[0056] Figure 3 (b) shows an example of a state where the generation amount of oxygen radicals (O ＊ ) is stable after a certain period of time. As Figure 3 shown in (b), according to the magnitude relationship between the etching rate of the reaction by-product 200 and the deposition rate of the reaction by-product 200, it is divided into two regions 301 and 302.

[0057] The region 301 on the side closer to the plasma generation region is a region where the etching rate of the reaction by-product 200 attached to the surface of the cover ring 26C is higher than the deposition rate of the reaction by-product 200. In the region 301, the cover ring 26C is exposed, and oxygen radicals (O ＊ ) are generated due to exposure to the plasma.

[0058] The region 302 outside the region 301 is a region where the etching rate of the reaction by-product 200 attached to the surface of the cover ring 26C is lower than the deposition rate of the reaction by-product 200. In the region 302, the reaction by-product 200 adheres, and the cover ring 26C is covered. Therefore, the generation of oxygen radicals (O ＊ ) from the region 302 is suppressed. In addition, the reaction by-product 200 adheres to the region 302, and the cover ring 26C is covered, so that the oxygen radicals (O ＊Stabilization of the production amount.

[0059] Thus, in the plasma processing apparatus of the reference example, the amount of oxygen radicals (O ＊ ) generated that affects the etching characteristics of the substrate W changes (decreases) from the initial state (refer to Figure 3 (a)) to the stable state after a certain period of time (refer to Figure 3 (b)). Therefore, during the process from the initial state to the stable state, the etching characteristics of the substrate W change.

[0060] In contrast, in the initial state of the plasma processing apparatus 1 of the present embodiment, as shown in Figure 2 (a), the upper surface 111 of the base member 110 is exposed to the internal space 10s, and the inclined surface 112 and the outer side surface 113 are covered by the cover member 120. Therefore, when the etching process is performed on the substrate W, the upper surface 111 of the base member 110 exposed to the plasma is consumed, and oxygen radicals (O ＊ ) are generated from the base member 110. On the other hand, the inclined surface 112 and the outer side surface 113 of the base member 110 are covered by the cover member 120. Therefore, the generation of oxygen radicals (O ＊ ) from the inclined surface 112 and the outer side surface 113 is suppressed. In other words, in the initial state, oxygen radicals (O ＊ ) are generated from the surface (upper surface 111) of the cover ring 26 in the region 301, and the generation of oxygen radicals (O ＊ ) from the surface (inclined surface 112, outer side surface 113) of the cover ring 26 in the region 302 is suppressed.

[0061] Moreover, as shown in Figure 2 (b), according to the magnitude relationship between the etching rate of the reaction by-product 200 and the deposition rate of the reaction by-product 200, it is divided into two regions 301 and 302.

[0062] In the region 301 where the etching rate is higher than the deposition rate, the base member 110 is exposed, and oxygen radicals (O ＊ ) are generated due to exposure to the plasma.

[0063] For the region 302 where the etching rate is lower than the deposition rate, the reaction by-product 200 adheres to the surface of the cover member 120, and the base member 110 is covered by the cover member 120 and / or the reaction by-product 200. Therefore, the generation of oxygen radicals (O ＊ ) from the region 302 is suppressed. In addition, the reaction by-product 200 adheres to the region 302, covering the cover ring 26, thereby stabilizing the amount of oxygen radicals (O ＊ ) generated from the cover ring 26.

[0064] According to the present embodiment, the generation amount of oxygen radicals (O ＊ ) in the initial state can be suppressed, and the generation amount of oxygen radicals (O ＊ ) after stabilization can be approached. In addition, the time until the generation amount of oxygen radicals (O ＊ ) becomes a stable state can be shortened.

[0065] In addition, preferably, in the cover ring 26 in the initial state, the base member 110 in the region 301 is exposed, but it is also possible that at least a part of the base member 110 in the region 301 is covered by the cover member 120. The cover member 120 in the region 301 is rapidly consumed by the plasma to expose the base member 110. The base member 110 exposed due to the consumption of the cover member 120 also generates oxygen radicals (O ＊ ) due to exposure to the plasma. In addition, due to the consumption of the cover member 120 in the region 301, the generation amount of oxygen radicals (O ＊ ) from the cover ring 26 is stabilized.

[0066] In addition, the region 301 where the etching rate is higher than the deposition rate and the region 302 where the etching rate is lower than the deposition rate are different according to the mechanical differences and process conditions of the plasma processing apparatus 1. In the plasma processing apparatus 1 of the present embodiment, since the cover member 120 in the region 301 is rapidly consumed, the time until the generation amount of oxygen radicals (O ＊ ) becomes a stable state can be shortened.

[0067] In addition, the cover member 120 may also be formed in the region 302 and the region near the boundary between the region 301 and the region 302. In other words, within the range clearly becoming the region 301, the cover member 120 is not formed and the base member 110 is exposed. In addition, within the range clearly becoming the region 302, the cover member 120 is formed. In addition, within the range near the boundary where it is not clearly the region 301 or the region 302, the cover member 120 is formed. Thereby, the change in the generation amount of oxygen radicals (O ＊ ) from the initial state to the stable state can be suppressed. In addition, the time until the generation amount of oxygen radicals (O ＊ ) becomes a stable state can be shortened. In addition, it is not necessary to separately change the position where the cover member 120 is formed according to the mechanical differences and process conditions of the plasma processing apparatus 1, and the manufacturing cost of the cover ring 26 can be reduced.

[0068] In addition, the cover member 120 uses a material having the same elements as the elements of the reaction by-product 200, so that when the cover member 120 is consumed by the plasma, the influence on the process characteristics can be suppressed. In addition, the cover member 120 is formed of a material not containing oxygen element (O), so as to suppress the influence on the process characteristics.

[0069] Figure 4 This is an example of the top view of the cover ring 26. Additionally, in Figure 4 it is illustrated by marking points on the area covered by the covered member 120.

[0070] The cover ring 26 has: a base member 110 which forms an upper surface 111 on the inner peripheral side and an inclined surface 112 on the outer peripheral side; and a cover member 120 which covers a part of the surface of the base member 110.

[0071] Here, in Figure 1 the plasma processing apparatus 1 shown, reaction by-products generated when the insulating film of the substrate W is etched are discharged from the internal space 10s to the outside through the exhaust port 12e by the exhaust device 50. Therefore, the deposition rate of the reaction by-products is asymmetric with respect to the circumferential direction of the cover ring 26, and the deposition rate on the exhaust port 12e side is higher. That is, sometimes the region 301 (refer to Figure 2 ) and the region 302 (refer to Figure 2 ) are asymmetric with respect to the circumferential direction of the cover ring 26. In Figure 4 when viewed from the center of the cover ring 26, the exhaust port 12e is provided on the lower left side. As shown in (a) of Figure 4 , the area covered by the covered member 120 may also be eccentric. In addition, as shown in (b) of Figure 4 , the area covered by the covered member 120 may also be different in the circumferential direction. According to such a structure, corresponding to the imbalance between the regions 301 and 302, by changing the range where the cover member 120 is formed, it is possible to suppress the change in the generation amount of oxygen radicals (O ＊ ) from the initial state to the stable state. In addition, it is possible to shorten the time until the generation amount of oxygen radicals (O ＊ ) becomes the stable state.

[0072] In addition, in the plasma processing apparatus 1, an example is described in which the cover member 120 is used to cover a part of the surface of the base member 110 of the cover ring 26 that is exposed to the internal space 10s, but it is not limited to this. Figure 5 This is an example of a partial enlarged view of the plasma processing apparatus 1 of another embodiment.

[0073] As Figure 5 shown in (a) of, for the member 33 disposed above the internal space 10s, a part of the surface exposed to the internal space 10s may also be covered by the cover member 140. That is, the member 33 has a base member 130 and a cover member 140.

[0074] The base member 130 is an annular member provided so as to surround the top plate 34, and is formed of a material (for example, SiO2) containing an element that affects process characteristics, specifically oxygen element (O).

[0075] Similar to the lid member 120 (refer to Figure 2 ), the lid member 140 is formed of a material that does not contain an element that affects process characteristics, specifically oxygen element (O). In addition, the lid member 140 is formed of the same material as the reaction by-products generated by the process of the plasma processing apparatus 1. Further, preferably, the lid member 140 is made of a material with a higher consumption rate caused by plasma compared to the base member 130 (for example, SiO2). In other words, preferably, the lid member 140 is made of a material with lower plasma resistance compared to the base member 130.

[0076] The lid member 140 is formed to cover a part of the surface of the base member 130 that is exposed toward the internal space 10s. The lid member 140 is formed, for example, in a region where the etching rate is lower than the deposition rate (for example, the outer peripheral side of the lid member 140).

[0077] In addition, as shown in (b) of Figure 5 , a part of the surface of the shield 46 that is exposed toward the internal space 10s can also be covered by the lid members 161 and 162. That is, the shield 46 has a base member 150 and lid members 161 and 162.

[0078] As described above, the inner peripheral surface of the base member 150 of the shield 46 is covered with, for example, an acid-resistant aluminum layer and a yttrium oxide film. The acid-resistant aluminum layer and the yttrium oxide film are also exposed to plasma, and thus are slightly consumed to generate oxygen radicals (O ＊ ).

[0079] Similar to the lid member 120 (refer to Figure 2 ), the lid members 161 and 162 are formed of a material that does not contain an element that affects process characteristics, specifically oxygen element (O). In addition, the lid members 161 and 162 are formed of the same material as the reaction by-products generated by the process of the plasma processing apparatus 1. Further, preferably, the lid members 161 and 162 are made of a material with a higher consumption rate caused by plasma compared to the base member 150. In other words, preferably, the lid members 161 and 162 are made of a material with lower plasma resistance compared to the base member 150.

[0080] The lid members 161 and 162 are formed to cover a part of the surface of the base member 150 that is exposed to the internal space 10s. The lid member 161 is formed, for example, in a region where plasma hardly reaches and the etching rate is lower than the deposition rate (e.g., the upper surface of the base member 150). In addition, the lid member 162 is formed, for example, in a region where the deposition rate is high on the flow path from the internal space 10s to the exhaust port 12e (refer to Figure 1 ) (e.g., the side wall of the base member 150 near the partition plate 48).

[0081] According to such a structure, not only the lid member 120 but also the members (member 33, shield 46) disposed in the internal space 10s can suppress the amount of oxygen radicals (O ＊ ) generated in the initial state and approach the amount of oxygen radicals (O ＊ ) generated after stabilization. In addition, the time until the amount of oxygen radicals (O ＊ ) generated reaches a steady state can be shortened.

[0082] As described above, the embodiments of the plasma processing apparatus 1 and the like have been described, but the present disclosure is not limited to the above embodiments and the like, and various modifications and improvements can be made within the scope of the gist of the present disclosure described in the claims.

Claims

1. A plasma processing apparatus, wherein, the plasma processing apparatus includes: a stage for placing a substrate; a chamber for accommodating the stage; a gas supply unit for supplying a processing gas into the chamber; a plasma generation unit for generating plasma in the chamber; a consumable member disposed in the space where the plasma is generated and consumed by the plasma; and a control unit, the consumable member has: a base member formed of a material containing oxygen element; and a cover member formed of a material not containing oxygen element, at least a part of the surface of the base member exposed to the space where the plasma is generated is covered by the cover member, the consumable member has: a first region where the etching rate of reaction by-products during plasma processing of the substrate is higher than the deposition rate of the reaction by-products; and a second region where the etching rate of the reaction by-products is lower than the deposition rate of the reaction by-products, in the first region, at least a part of the base member is exposed.

2. The plasma processing apparatus according to claim 1, wherein, the material of the cover member has lower plasma resistance than the material of the base member.

3. The plasma processing apparatus according to claim 1 or 2, wherein, the material of the cover member contains the same elements as the reaction by-products during plasma processing of the substrate.

4. The plasma processing apparatus according to claim 3, wherein, the material of the cover member is formed of a material containing carbon element and fluorine element.

5. The plasma processing apparatus according to claim 1, wherein, in the second region, the base member is covered by the cover member.

6. The plasma processing apparatus according to claim 1 or 2, wherein, the processing by the plasma etches a silicon-containing film formed on the substrate.

7. The plasma processing apparatus according to claim 1 or 2, wherein, the base member of the consumable member is formed of SiO2, and the consumable member is an annular member disposed around the substrate.

8. The plasma processing apparatus according to claim 1 or 2, wherein, the base member of the consumable member is formed of SiO2, and the consumable member is an annular member disposed above the stage.

9. The plasma processing apparatus according to claim 1 or 2, wherein, the base member of the consumable member is covered with an oxide film, and the consumable member is a shield disposed on the outer peripheral surface of the stage and the inner peripheral surface of the chamber.

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