Method for manufacturing electrostatic chuck, electrostatic chuck, and substrate processing apparatus

Abstract

Provided is a manufacturing method of an electrostatic chuck capable of preventing abnormal discharge, an electrostatic chuck, and a substrate processing apparatus. A manufacturing method of an electrostatic chuck includes: a step of preparing a first ceramic plate in which a first hole is formed; a step of preparing a second ceramic plate in which a second hole is formed, the second hole being formed at a position different from that of the first hole in a horizontal direction; a step of forming a slurry layer on the first ceramic plate or the second ceramic plate using a slurry, the slurry layer being formed with a flow path connecting the first hole and the second hole; a step of stacking the first ceramic plate and the second ceramic plate with the slurry layer interposed therebetween; and a step of joining the first ceramic plate and the second ceramic plate stacked with the slurry layer interposed therebetween.

Description

Technical Field

[0001] This disclosure relates to a method for manufacturing an electrostatic chuck, an electrostatic chuck, and a substrate processing apparatus. Background Technology

[0002] In semiconductor manufacturing processes, it is known that, in order to improve the thermal conductivity between the substrate and the electrostatic chuck, a heat-conducting gas is supplied from a through-hole provided in the electrostatic chuck to the tiny space between the substrate and the electrostatic chuck (for example, Patent Document 1).

[0003] Furthermore, Patent Document 2 discloses an electrostatic chuck comprising: a substrate formed of ceramic, having a holding surface on its upper surface and a flow path for a heat medium inside; and a coating film covering the inner surface of the flow path. The coating film is formed of a ceramic that is harder than the ceramic of the substrate.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: International Publication No. 2003 / 046969

[0007] Patent Document 2: International Publication No. 2014 / 098224 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] This disclosure provides a method for manufacturing an electrostatic chuck capable of preventing abnormal discharge, an electrostatic chuck, and a substrate processing apparatus.

[0010] Solution for solving the problem

[0011] According to a technical solution of this disclosure, a method for manufacturing an electrostatic chuck is provided. The method includes: a step of preparing a first ceramic plate having a first hole formed therein; a step of preparing a second ceramic plate having a second hole formed therein, the second hole being formed in the horizontal direction at a position different from that of the first hole; a step of forming a slurry layer on the first ceramic plate or the second ceramic plate using slurry, the slurry layer forming a flow path connecting the first hole and the second hole; a step of stacking the first ceramic plate and the second ceramic plate with the slurry layer in between; and a step of joining the first ceramic plate and the second ceramic plate stacked with the slurry layer in between.

[0012] The effects of the invention

[0013] According to a technical solution, a method for manufacturing an electrostatic chuck that can prevent abnormal discharge, an electrostatic chuck, and a substrate processing apparatus can be provided. Attached Figure Description

[0014] Figure 1 This is a cross-sectional schematic diagram illustrating an example of a substrate processing apparatus according to one embodiment.

[0015] Figure 2 This is a diagram illustrating an example of the flow path formed by an electrostatic chuck in one embodiment.

[0016] Figure 3 It means Figure 2 A diagram of an example of an AA section.

[0017] Figure 4 This is a flowchart illustrating an example of a method for manufacturing an electrostatic chuck according to one embodiment.

[0018] Figure 5 This is a diagram illustrating an example of a method for manufacturing an electrostatic chuck according to one embodiment.

[0019] Figure 6 This is a diagram illustrating another example of a method for manufacturing an electrostatic chuck according to one embodiment.

[0020] Figure 7 It means Figure 2 A diagram of another example of an AA section.

[0021] Figure 8 It means Figure 2 A diagram of another example of an AA section.

[0022] Figure 9 This is a flowchart illustrating an example of a method for manufacturing (regenerating) an electrostatic chuck according to one embodiment. Detailed Implementation

[0023] The embodiments used to implement this disclosure will now be described with reference to the accompanying drawings. In the drawings, the same reference numerals are used to label the same constituent parts, and repeated descriptions are omitted.

[0024] [Substrate Processing Apparatus]

[0025] use Figure 1 The substrate processing apparatus 1 of one embodiment will be described. Figure 1This is a cross-sectional schematic diagram illustrating an example of a substrate processing apparatus 1 according to one embodiment. The substrate processing apparatus 1 includes a processing container 10. The processing container 10 provides a processing space 10s inside. The processing container 10 includes a main body 12. The main body 12 has a generally cylindrical shape. The main body 12 is formed of, for example, aluminum. A corrosion-resistant film is provided on the inner wall surface of the main body 12. This film is preferably a ceramic such as alumina or yttrium oxide.

[0026] A passage 12p is formed on the side wall of the main body 12. The substrate W is transported between the processing space 10s and the outside of the processing container 10 via the passage 12p. The passage 12p is opened and closed by a gate valve 12g provided along the side wall of the main body 12.

[0027] A support portion 13 is provided on the bottom of the main body 12. The support portion 13 is formed of an insulating material. The support portion 13 has a generally cylindrical shape. The support portion 13 extends upward from the bottom of the main body 12 in the processing space 10s. The support portion 13 has a mounting stage 14 at its upper part. The mounting stage 14 is configured to support the substrate W in the processing space 10s.

[0028] The stage 14 has a base 18 and an electrostatic chuck 20. The stage 14 may also have an electrode plate 16. The electrode plate 16 is formed of a conductor such as aluminum and has a generally disc shape. The base 18 is disposed on the electrode plate 16. The base 18 is formed of a conductor such as aluminum and has a generally disc shape. The base 18 is electrically connected to the electrode plate 16.

[0029] An electrostatic chuck 20 is mounted on the mounting surface of the base 18, and a substrate W is mounted on the mounting surface 20a of the electrostatic chuck 20. The main body of the electrostatic chuck 20 has a generally disc-shaped form. The electrostatic chuck 20 is formed of a dielectric such as ceramic.

[0030] An electrode 20b is embedded in the electrostatic chuck 20 in a manner parallel to the mounting surface 20a. The electrode 20b is a film-shaped electrode. The electrode 20b is connected to a DC power supply 51 via a switch (not shown). When a DC voltage is applied to the electrode 20b from the DC power supply 51, an electrostatic attraction is generated between the electrostatic chuck 20 and the substrate W. Using this electrostatic attraction, the substrate W is held in the electrostatic chuck 20.

[0031] The electrostatic chuck 20 has a stepped portion around the substrate, and an edge ring 25 is disposed on the upper surface of the stepped portion. The edge ring 25 improves the in-plane uniformity of the plasma treatment performed on the substrate W. The edge ring 25 can be formed of silicon, silicon carbide, or quartz, etc. The edge ring 25 is an example of a ring member located around the substrate, also known as a focusing ring.

[0032] A flow path 22a is formed inside the electrostatic chuck 20, between the mounting surface 20a and the electrode 20b. A first hole 21a is formed on the mounting surface 20a. A second hole 23a is formed on the lower surface 20c of the electrostatic chuck 20. The first hole 21a and the second hole 23a are connected via the flow path 22a. The second hole 23a is connected to a gas source 52 via a gas supply line 24 that penetrates the base 18 and the electrode plate 16. The gas source 52 supplies a heat-conducting gas (e.g., He gas). The heat-conducting gas is supplied between the mounting surface 20a of the electrostatic chuck 20 and the back surface of the substrate W via the gas supply line 24, the second hole 23a, the flow path 22a, and the first hole 21a.

[0033] In the base 18, a flow path 19a is formed inside for the flow of a temperature-regulating medium such as refrigerant. The temperature-regulating medium flows from the cooling unit 26 through the inlet pipe 19b, through the flow path 19a, and returns to the cooling unit 26 through the outlet pipe 19c. Thus, the temperature of the substrate W placed on the electrostatic chuck 20 is adjusted by controlling the heat-conducting gas and the temperature-regulating medium.

[0034] The substrate processing apparatus 1 includes a first high-frequency power supply 62 and a second high-frequency power supply 64. The first high-frequency power supply 62 supplies high-frequency power at a first frequency suitable for plasma generation. The first frequency may also be, for example, a frequency in the range of 27 MHz to 100 MHz. The first high-frequency power supply 62 is connected to the electrode plate 16 via a matching adapter 66. The matching adapter 66 matches the output impedance of the first high-frequency power supply 62 with the impedance of the load side (plasma side). Furthermore, the first high-frequency power supply 62 may also be connected to the upper electrode 30 via the matching adapter 66. The first high-frequency power supply 62 constitutes an example plasma generation unit.

[0035] The second high-frequency power supply 64 supplies high-frequency power at a second frequency suitable for ion inhalation. This second frequency is different from the first frequency and can be, for example, a frequency in the range of 400 kHz to 13.56 MHz. The second high-frequency power supply 64 is connected to the electrode plate 16 via a matching adapter 68. The matching adapter 68 matches the output impedance of the second high-frequency power supply 64 to the impedance of the load side (plasma side).

[0036] Alternatively, high-frequency power at a second frequency can be used instead of the first frequency to generate plasma. In this case, the second frequency can also be a frequency greater than 13.56 MHz, such as 40 MHz. In this case, the substrate processing apparatus 1 may not include the first high-frequency power supply 62 and the matching device 66. The second high-frequency power supply 64 constitutes an example plasma generation unit.

[0037] The upper electrode 30 is positioned opposite the stage 14, and the upper opening of the main body 12 of the processing container 10 is sealed by an insulating member 32. The upper electrode 30 has a top plate 34 and a support 36. The lower surface of the top plate 34 is the lower surface of the processing space 10s, dividing the processing space 10s. The top plate 34 can 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 extending through the top plate 34 in its thickness direction.

[0038] The support body 36 supports the top plate 34 in a manner that allows for easy assembly and disassembly. 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 multiple vents 36b extending downward from the gas diffusion chamber 36a. The multiple vents 36b are respectively connected to multiple gas ejection holes 34a. 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.

[0039] A valve assembly 42, a flow controller assembly 44, and a gas source assembly 40 are connected to the gas supply pipe 38. The gas source assembly 40, valve assembly 42, and flow controller assembly 44 constitute the gas supply unit. The gas source assembly 40 includes multiple gas sources. The valve assembly 42 includes multiple on / off valves. The flow controller assembly 44 includes multiple flow controllers. The multiple flow controllers in the flow controller assembly 44 are either mass flow controllers or pressure-controlled flow controllers. The multiple gas sources in the gas source assembly 40 are connected to the gas supply pipe 38 via corresponding on / off valves in the valve assembly 42 and corresponding flow controllers in the flow controller assembly 44.

[0040] In the substrate processing apparatus 1, a shielding member 46 is provided along the inner wall surface of the main body 12 and the outer periphery of the support portion 13 in a detachable manner. The shielding member 46 is used to prevent reaction byproducts from adhering to the main body 12. The shielding member 46 is formed, for example, by forming a corrosion-resistant film on the surface of a base material formed of aluminum. The corrosion-resistant film can be formed of ceramics such as yttrium oxide.

[0041] A baffle 48 is provided between the support portion 13 and the side wall of the main body 12. The baffle 48 is formed, for example, by forming a corrosion-resistant film (such as a yttrium oxide film) on the surface of a base material made of aluminum. Multiple through holes are formed in the baffle 48. An exhaust port 12e is provided below the baffle 48, at the bottom of the main body 12. An exhaust device 50 is connected to the exhaust port 12e via an exhaust pipe 53. The exhaust device 50 includes a pressure regulating valve and a vacuum pump such as a turbomolecular pump.

[0042] Within the processing container 10, processing gas is supplied to the processing space 10s. Additionally, high-frequency electricity of a first frequency and / or a second frequency is applied to the stage 14, thereby generating a high-frequency electric field between the upper electrode 30 and the base 18, and plasma is generated from the gas due to discharge.

[0043] The substrate processing apparatus 1 may also include a control unit 80. The control unit 80 may be a computer equipped with a processor, a memory, an input device, a display device, and signal input / output interfaces. The control unit 80 is used to control various parts of the substrate processing apparatus 1. In the control unit 80, an operator can use the input device to input commands and manage the substrate processing apparatus 1. Furthermore, the control unit 80 can use the display device to visualize the operating status of the substrate processing apparatus 1. Moreover, the storage unit stores control programs and process data. The control program is executed by the processor to perform various processes on the substrate processing apparatus 1. The processor executes the control program and controls various parts of the substrate processing apparatus 1 according to the process data.

[0044] [flow path]

[0045] Then, while referring to Figure 2 and Figure 3 The flow path 22a formed inside the electrostatic chuck 20 for the flow of heat-conducting gas will be explained. Figure 2 This is a diagram showing an example of a flow path 22a formed by an electrostatic chuck 20 in one embodiment. Figure 3 It means Figure 2 A diagram of an example of an AA section.

[0046] Figure 2 This is a top-view view of the flow path 22a formed inside the electrostatic chuck 20. The flow path 22a includes: a flow path 22a1, which is formed in a roughly inverted C shape inside the electrostatic chuck 20; one flow path 22a2, which branches inward from the flow path 22a1; and six flow paths 22a3, which branch outward from the flow path 22a1. Flow path 22a1 is an example of a main flow path, and flow paths 22a3 are examples of secondary flow paths.

[0047] Six first holes 21a are formed on concentric circles and connected to flow path 22a1 via six flow paths 22a3. However, the number of first holes 21a is not limited to this. Second holes 23a are formed approximately at the center of the electrostatic chuck 20 and connected to flow path 22a1 via flow path 22a2. The opening of the first hole 21a is smaller than the opening of the second hole 23a. That is, the area of ​​the opening of the first hole 21a is smaller than the area of ​​the opening of the second hole 23a. The shapes of the first holes 21a and the second holes 23a can be circles, quadrilaterals, or other polygons.

[0048] The manufacturing method of the electrostatic chuck 20 according to the embodiments discussed below, such as as Figure 2 AA section Figure 3 As shown, the electrostatic chuck 20 includes: a first ceramic plate 21 having a first hole 21a; and a second ceramic plate 23 having a second hole 23a, which are stacked on top of the first ceramic plate 21. Furthermore, a flow path 22a (flow path 22a1 to flow path 22a3) of a desired height is formed between the stacked first ceramic plate 21 and second ceramic plate 23, connecting the first hole 21a and the second hole 23a. The height of the flow path 22a is set to a desired height. As an example, the height of the flow path 22a is 5 μm to 30 μm.

[0049] The second hole 23a and the six first holes 21a are formed in a non-overlapping position when viewed from above. That is, the second hole 23a is formed in a different position in the horizontal direction than the six first holes 21a. In addition, in the manufacturing method of the electrostatic chuck 20 of the embodiment, the height of the flow path 22a can be reduced to a range of 5μm to 30μm.

[0050] return Figure 2 The width of flow path 22a1, an example of a main flow path, is wider than the width of flow path 22a3, an example of a secondary flow path. A gas source 52 is connected to flow path 22a1 via gas supply line 24 and flow path 22a2. Thus, after the heat-conducting gas supplied from gas source 52 diffuses in the space of flow path 22a1, which is wider than flow path 22a3, it is supplied into the space of flow path 22a3, which is narrower than flow path 22a1. This allows the heat-conducting gas to be uniformly introduced between the mounting surface 20a of the electrostatic chuck 20 and the back surface of the substrate W.

[0051] In addition, used to form Figure 3 The slurry layer 22 of the flow path 22a shown is formed by applying slurry between the first ceramic plate 21 and the second ceramic plate 23 during the manufacture of the electrostatic chuck 20. For convenience, in Figure 3 The slurry layer 22 is positioned between the first ceramic plate 21 and the second ceramic plate 23. However, when manufacturing the electrostatic chuck 20, if the first ceramic plate 21 and the second ceramic plate 23 are fired in a state where they are stacked together with the slurry layer 22 in between, then the first ceramic plate 21 and the second ceramic plate 23 are bonded together and integrated with the slurry layer 22. That is, a single ceramic plate 28 is formed by the first ceramic plate 21, the second ceramic plate 23, and the slurry layer 22. Therefore, in the fired electrostatic chuck 20, the slurry layer 22 does not exist as a layer, but rather becomes a space within the ceramic plate 28 where the flow path 22a1 is formed.

[0052] In this embodiment, the electrostatic chuck 20 is configured such that the heat-conducting gas supplied to the second hole 23a formed on the lower surface of the ceramic plate 28 is supplied to the back side of the substrate W via a flow path 22a provided inside the ceramic plate 28 from the first hole 21a. Therefore, compared to the case where the heat-conducting gas supply hole (first hole 21a) provided on the mounting surface 20a is a through hole penetrating the ceramic plate 28, the longitudinal length of the hole can be shortened. Consequently, the acceleration of electrons within the first hole 21a is suppressed, and discharge within the first hole 21a can be suppressed.

[0053] Furthermore, the first hole 21a is provided via a flow path 22a provided inside the ceramic plate 28. Therefore, the first hole 21a can be provided without being restricted by the shape of the flow path 19a provided on the base 18. Thus, it becomes easy to provide multiple first holes 21a with smaller openings. By reducing the opening of the first hole 21a, it is possible to reduce the specific temperature point relative to the substrate W on the mounting surface 20a, thereby improving temperature control.

[0054] Furthermore, the second hole 23a is formed in a different position in the horizontal direction than the first hole 21a. That is, the first hole 21a and the second hole 23a are not arranged in a straight line. Therefore, during processes such as cleaning within the processing container 10, it is possible to suppress plasma from entering the second hole 23a and the gas supply line 24 when plasma is generated without the substrate W. Therefore, it is possible to arrange a component made of a material with low plasma resistance inside or on the wall of the second hole 23a or the gas supply line 24.

[0055] In addition, Figure 3 In one example shown, electrode 20b is disposed below flow path 22a, but it can also be formed above flow path 22a. However, since the longitudinal length of the first hole 21a can be further shortened, it is preferable that electrode 20b is disposed below flow path 22a.

[0056] [Manufacturing method of electrostatic chuck]

[0057] Then, while referring to Figure 4 and Figure 5 An example of a method for manufacturing an electrostatic chuck 20 will be explained. Figure 4 This is a flowchart illustrating an example of a method for manufacturing an electrostatic chuck 20 according to one embodiment. Figure 5 This is a diagram illustrating an example of a method for manufacturing an electrostatic chuck 20 according to one embodiment.

[0058] If start Figure 4The process involves preparing a first ceramic plate 21 having a first hole 21a and being fired, and a second ceramic plate 23 having a second hole 23a and being fired (step S1). Preferably, the first ceramic plate 21 and the second ceramic plate 23 are sintered bodies of alumina (Al2O3) (hereinafter also referred to as "alumina") or sintered bodies of alumina with added silicon carbide (SiC). The first ceramic plate 21 and the second ceramic plate 23 can be made of the same material or different materials.

[0059] For example, in Figure 5 Example of a first ceramic plate 21 and a second ceramic plate 23 is shown in (b). The first ceramic plate 21 and the second ceramic plate 23 are disc-shaped plate members of the same size with the same diameter. The first ceramic plate 21 is pre-fired and has six first holes 21a formed therein. Similarly, the second ceramic plate 23 is pre-fired and has one second hole 23a formed therein.

[0060] exist Figure 4 In the next step, a dielectric paste layer 22 having flow paths 22a is formed on the second ceramic plate 23 using screen printing (step S2). Thus, as... Figure 5 As shown in (b), a slurry layer 22 having flow paths 22a (flow paths 22a1, 22a2, 22a3) is formed on the second ceramic plate 23. Specifically, the portions used to form flow paths 22a1, 22a2, 22a3 are covered, and slurry 22b is applied to the remaining portions. Thus, a slurry layer 22 is formed on the second ceramic plate 23, in which the portions used to form flow paths 22a1, 22a2, 22a3 become spaces.

[0061] The slurry 22b applied to form the slurry layer 22 is made by mixing (dispersing) alumina powder or alumina powder with added silicon carbide into a solvent, and is also called a paste. The solvent is a fluorine-based or phenol-based solution, and the alumina powder or the like is mixed with the solution. In addition, in step S2, the slurry layer 22 may also be formed on the surface of the first ceramic plate 21.

[0062] exist Figure 4 In the next step, the first ceramic plate 21 and the second ceramic plate 23 are stacked with the slurry layer 22 in between (step S3). Thus, the first ceramic plate 21 and the second ceramic plate 23 are stacked with the slurry layer 22 in between.

[0063] exist Figure 4 In the next step, pressure is applied in the vertical direction while firing, thereby joining the first ceramic plate 21 and the second ceramic plate 23 stacked with the slurry layer 22 in between (step S4), and the process ends.

[0064] In the manufacturing method of this electrostatic chuck 20, the first ceramic plate 21 and the second ceramic plate 23 are fired in a state where they are stacked with a slurry layer 22 in between, thereby joining the first ceramic plate 21 and the second ceramic plate 23. As a result, the first ceramic plate 21, the slurry layer 22, and the second ceramic plate 23 are integrated into a ceramic plate 28, and the slurry layer 22 disappears. Consequently, a flow path 22a is formed inside the integrated ceramic plate 28. Since the slurry layer 22 is paste-like, the flow path 22a can be formed to a height of 5 μm to 30 μm. This allows the flow path 22a to be formed thinner, thus shortening the longitudinal length of the first hole 21a.

[0065] Figure 5 Figure (a) is a comparative example of a method for manufacturing an electrostatic chuck using a slurry formed under pressure and then solidified into a green sheet.

[0066] exist Figure 5 In example (a), a green sheet 121 serving as the upper plate, a green sheet 122 having a flow path 122a, and a green sheet 123 serving as the lower plate are stacked. After applying a slurry between the stacked green sheets 121, 122, and 123, the sheets are fired.

[0067] Figure 5 The green sheets 121, 122, and 123 shown in (a) are before firing, and therefore are softer than the first ceramic plate 21 and the second ceramic plate 23 after firing. Therefore, when using green sheets, if firing is performed while applying pressure as in the manufacturing method of the electrostatic chuck 20 of this embodiment, there is a possibility that the green sheets 121, 122, and 123 will deform. Therefore, it is difficult to fire the green sheets while applying pressure. Furthermore, the green sheet 122 with the flow path 122a is a separate sheet from the other two green sheets 121 and 123, and therefore requires a certain thickness, making it difficult to form a flow path 122a of 5μm to 30μm as in this embodiment.

[0068] In contrast, in the manufacturing method of the electrostatic chuck 20 of this embodiment, a slurry layer 22 with a thickness of approximately 5 μm to 30 μm is applied between the first ceramic plate 21 and the second ceramic plate 23 before firing. At this time, the first ceramic plate 21 and the second ceramic plate 23 are pre-fired, resulting in higher strength compared to raw sheets. Therefore, even when pressure is applied to the first ceramic plate 21 and the second ceramic plate 23 during firing, no deformation occurs, and the first ceramic plate 21 and the second ceramic plate 23 can be pressed and fixed during firing.

[0069] According to the manufacturing method of the electrostatic chuck 20 of the embodiment, the longitudinal length of the first hole 21a can be shortened. This prevents abnormal discharge from occurring in and around the first hole 21a.

[0070] Furthermore, electrode 20b can be pre-formed in... Figure 4 The first ceramic plate 21 or the second ceramic plate 23 prepared in step S1 can also be formed in step S4. If the electrode 20b is formed in step S4, a third ceramic plate is prepared in step S1, which has a hole formed at the same position as the second hole 23a of the second ceramic plate 23. A conductive paste is applied to the third ceramic plate, and in step S3, the second ceramic plate 23 is stacked on top of the third ceramic plate. By firing in step S4, an electrostatic chuck 20 with the electrode 20b below the flow path 22a can be obtained. When the electrode 20b is placed above the flow path 22a, a ceramic plate with a hole formed at the same position as the first hole 21a of the first ceramic plate 21 can be prepared as the third ceramic plate, and can be manufactured using the same steps. However, since the diameter of the first hole 21a is smaller than the diameter of the second hole 23a, and the number of first holes 21a is greater than the number of second holes 23a, precise alignment is required. Therefore, it is preferable to form electrode 20b below flow path 22a.

[0071] [Flow path within the electrode]

[0072] In the manufacturing method of the electrostatic chuck 20 according to the embodiment, a flow path can also be formed within the electrode 20b. That is, a slurry layer can also be used to form... Figure 3 Electrode 20b is shown. Figure 6 This is a diagram illustrating another example of a method for manufacturing an electrostatic chuck 20 according to one embodiment. Figure 7 It means Figure 2 A diagram of another example of an AA section.

[0073] Here, it is formed on the second ceramic plate 23. Figure 6 The conductive paste layer 20b1 shown is used to replace Figure 5 The dielectric slurry layer 22 shown in (b). In this case, as... Figure 2 Another example of an AA section Figure 7 As shown, Figure 1 The electrode 20b shown is formed from a conductive paste layer 20b1, and a flow path 22a is formed inside the conductive paste layer 20b1. The flow path 22a has flow paths 22a1 to 22a3, which is similar to... Figure 5 The flow path 22a shown in (b) is similar, therefore, its description is omitted here. Furthermore, the shape of the flow path 22a is not limited to... Figure 5 (b) and Figure 6 The example shown can be any structure as long as it can connect the first hole 21a and the second hole 23a, and the first hole 21a and the second hole 23a are formed at different positions in the horizontal direction.

[0074] In order to form Figure 7 The paste 20b11 applied to the paste layer 20b1 of electrode 20b (refer to) Figure 6 It is made by mixing (dispersing) conductive powder in a solvent. The solvent is a fluorine-based or phenol-based solution, which mixes the conductive powder with the solution. The conductive powder can also be any of tungsten carbide (WC), molybdenum carbide (MoC), or tantalum carbide (TaC).

[0075] If the slurry layer 20b1 of the conductor is exposed between the first ceramic plate 21 and the second ceramic plate 23, the conductor will be exposed to plasma, becoming a cause of metal contamination within the processing container 10. Therefore, as Figure 6 As shown, a paste 20b11 for forming a conductor is applied in a circular shape to the inner side of the second ceramic plate 23, and a paste 27b1 for forming a dielectric is applied in such a way that gaps are formed between the paste 20b11 and the paste 20b11 is covered on its outer periphery. The paste layer 20b1 for the conductor and the paste layer 27b for the dielectric are formed by screen printing. For example, the paste 20b11 for the conductor may be applied while covering the paste layer 27b and the gaps, and then the paste 27b1 for the dielectric may be applied while covering the paste layer 20b1 and the gaps, thereby forming the paste layer 27b for the dielectric.

[0076] In this way, a conductive slurry layer 20b1 and a dielectric slurry layer 27b, with a flow path 22a having a thickness of approximately 5 μm to 30 μm, are formed between the first ceramic plate 21 and the second ceramic plate 23 with a gap. By providing a gap, mixing of the conductive slurry layer 20b1 and the dielectric slurry layer 27b can be avoided. After forming the slurry layer 20b1 and the slurry layer 27b, the first ceramic plate 21, the slurry layer 20b1 and the slurry layer 27b, and the second ceramic plate 23 are stacked and fired under pressure. At this time, since the first ceramic plate 21 and the second ceramic plate 23 are pre-fired, they have a certain degree of strength. Therefore, even if pressure is applied to the first ceramic plate 21 and the second ceramic plate 23 during firing, deformation will not occur, and the first ceramic plate 21 and the second ceramic plate 23 can be pressed and fixed in the vertical direction. As a result, the first ceramic plate 21 and the second ceramic plate 23 are integrated with the slurry layer 20b1 and the slurry layer 27b to form a single unit. Figure 7 The electrode 20b and dielectric layer 27 are shown. This allows a flow path 22a of 5 μm to 30 μm to be formed inside the conductive member (electrode 20b). In this case, the flow path 22a is also connected to the first hole 21a and the second hole 23a, allowing for the flow of heat-conducting gas. Furthermore, the dielectric layer 27 covers the electrode 20b, thereby preventing the electrode 20b from being exposed to plasma and causing metal contamination.

[0077] [Porous flow path]

[0078] In the manufacturing method of the electrostatic chuck 20 of the embodiment, the slurry layer 22, slurry layer 20b1 and slurry layer 27b may be fired using the following method to form a porous layer having flow path 22a.

[0079] For example, if the temperature is constantly controlled between 1200°C and 1700°C during firing, it is difficult for the slurry layer to become porous. In contrast, by controlling the initial firing temperature to 700°C to 800°C, and then controlling it to 1200°C to 1700°C after a set time, a porous slurry layer can be formed. Alternatively, the slurry layer can be made porous by changing the ratio of slurry powder to solvent, and the porosity of the pores can also be altered.

[0080] Figure 8 It means Figure 2 A diagram of another example of the AA cross-section. This is achieved by forming a porous layer 29 with flow paths 22a, as shown... Figure 8 As shown, a portion of the side surface of the ceramic plate 28 becomes porous. If a heat-conducting gas such as helium flows into the flow path 22a, the heat-conducting gas enters the pores of the porous layer 29 from the flow path 22a, and leaks from the side surface of the ceramic plate 28. This prevents reaction products from adhering to the side surface of the electrostatic chuck 20.

[0081] [Regeneration of electrostatic chucks]

[0082] Then, while referring to Figure 9 The manufacturing method of the electrostatic chuck for the regeneration process will be explained. Figure 9 This is a flowchart illustrating an example of a method for manufacturing an electrostatic chuck during regeneration.

[0083] At the beginning Figure 9 During the processing, the first ceramic plate 21 is cut to expose the second ceramic plate 23 (step S11). Next, a new first ceramic plate 21 with the first hole 21a is prepared (step S12).

[0084] Next, a paste layer 22 is formed on the second ceramic plate 23 by screen printing. This paste layer 22 forms a flow path 22a connecting the first hole 21a and the second hole 23a (step S13). Alternatively, the paste layer 22 can be formed on a new first ceramic plate 21.

[0085] Next, the new first ceramic plate 21 and the second ceramic plate 23 are stacked with the slurry layer 22 in between (step S14). Then, the slurry layer 22 is fired to join the new first ceramic plate 21 and the second ceramic plate 23, thereby regenerating the electrostatic chuck 20 (step S15) and ending the process.

[0086] In this way, by replacing the first ceramic plate 21 exposed to plasma with a new first ceramic plate 21, the manufacturing method of the electrostatic chuck of the embodiment can regenerate the electrostatic chuck that can prevent abnormal discharge.

[0087] Furthermore, the slurry layer used in the manufacturing method of the electrostatic chuck 20 of this embodiment is not limited to a slurry layer formed by dispersing a predetermined powder in a fluorine-based or phenol-based solution. For example, the slurry layer used in the manufacturing method of the electrostatic chuck 20 of this embodiment can also be generated by adding a predetermined amount of solution, sintering aid, and binder, and then pulverizing it to a predetermined particle size. As the added sintering aid, B4C-based or rare earth oxide-Al2O3-based sintering aids can be used. In addition, as the added binder, a synthetic resin can be used. For example, the binder can be rosin ester, ethyl cellulose, ethyl hydroxyethyl cellulose, butyral resin, phenolic resin, polyethylene oxide resin, poly(2-ethyloxazoline) resin, polyvinylpyrrolidone resin, etc. The binder can also be polymethacrylic resin, polyvinyl alcohol resin, acrylic resin, polyvinyl butyral resin, alkyd resin, polybenzyl, polymethylene divinylbenzene, polystyrene, etc.

[0088] As explained above, the manufacturing method of the electrostatic chuck 20 according to this embodiment provides a method for manufacturing an electrostatic chuck that prevents abnormal discharge, an electrostatic chuck, and a substrate processing apparatus. Furthermore, the manufacturing method of the electrostatic chuck 20 according to this embodiment can regenerate an electrostatic chuck 20 that prevents abnormal discharge.

[0089] It should be considered that the method for manufacturing an electrostatic chuck, the electrostatic chuck, and the substrate processing apparatus disclosed herein are illustrative and not limiting in all respects. The above embodiments can be modified and improved in various forms without departing from the claims and their spirit. The matters described in the above embodiments can be adopted in other structures without contradiction, and can also be combined without contradiction.

[0090] For example, in Figure 3 In the example, the electrode 20b and the flow path 22a are provided only at the lower part of the mounting surface 20a of the mounting substrate W, but the electrode 20b and the flow path 22a may also be provided at the lower part of the stepped portion of the mounting edge ring 25.

[0091] The substrate processing apparatus disclosed herein is also applicable to any of the following types of apparatuses: Atomic Layer Deposition (ALD), Capacitively Coupled Plasma (CCP), Inductively Coupled Plasma (ICP), Radial Line Slot Antenna (RLSA), Electron Cyclotron Resonance Plasma (ECR), and Helicon Wave Plasma (HWP).

[0092] In addition, a plasma processing apparatus was given as an example of a substrate processing apparatus, but a substrate processing apparatus is any apparatus that performs a predetermined process (e.g., film formation, etching, etc.) on a substrate, and is not limited to a plasma processing apparatus.

Claims

1. A method for manufacturing an electrostatic chuck, wherein, The manufacturing method of this electrostatic chuck includes: The process of preparing the first ceramic plate with the first hole already formed; The process of preparing a second ceramic plate with a second hole formed thereon, the second hole being formed in the horizontal direction at a position different from that of the first hole; In the process of forming a slurry layer on the first ceramic plate or the second ceramic plate using slurry, the slurry layer forms a flow path connecting the first hole and the second hole, wherein the flow path is formed in the slurry layer by covering the portion used to form the flow path when forming the slurry layer; The process of stacking the first ceramic plate and the second ceramic plate with the slurry layer in between; and The process of joining the first ceramic plate and the second ceramic plate, which are stacked together with the slurry layers in between. The first ceramic plate and the second ceramic plate are sintered bodies.

2. The method for manufacturing an electrostatic chuck according to claim 1, wherein, The first ceramic plate and the second ceramic plate are sintered alumina bodies or sintered alumina bodies with added silicon carbide.

3. The method for manufacturing an electrostatic chuck according to claim 1 or 2, wherein, The slurry is formed by mixing alumina powder or alumina powder with added silicon carbide with a solvent.

4. The method for manufacturing an electrostatic chuck according to claim 1 or 2, wherein, The first ceramic plate or the second ceramic plate has electrodes.

5. The method for manufacturing an electrostatic chuck according to claim 1 or 2, wherein, The slurry is formed by mixing conductive powder with a solvent.

6. The method for manufacturing an electrostatic chuck according to claim 5, wherein, The conductive powder is any one of tungsten carbide, molybdenum carbide, and tantalum carbide.

7. The method for manufacturing an electrostatic chuck according to claim 1 or 2, wherein, The paste layer is formed using screen printing.

8. The method for manufacturing an electrostatic chuck according to claim 1 or 2, wherein, The flow path includes a main flow path and a secondary flow path. The secondary flow path is connected to the main flow path and is narrower than the width of the main flow path.

9. The method for manufacturing an electrostatic chuck according to claim 8, wherein, The main flow path is configured to connect with the second hole, and the secondary flow path is configured to connect with the first hole.

10. The method for manufacturing an electrostatic chuck according to claim 1 or 2, wherein, The opening of the first hole is smaller than the opening of the second hole.

11. The method for manufacturing an electrostatic chuck according to claim 1 or 2, wherein, The height of the flow path is 5μm to 30μm.

12. The method for manufacturing an electrostatic chuck according to claim 1 or 2, wherein, The manufacturing method of this electrostatic chuck includes: The process of cutting the first ceramic plate to expose the second ceramic plate; The process of preparing a new first ceramic plate having the first hole; The process of forming a slurry layer on a new first ceramic plate or second ceramic plate using slurry, the slurry layer forming a flow path connecting the first hole and the second hole; The process of stacking the new first ceramic plate and the second ceramic plate with the slurry layer in between; The process of regenerating an electrostatic chuck by joining new first ceramic plates and second ceramic plates stacked together with the slurry layers in between.

13. An electrostatic chuck, which is an electrostatic chuck having a ceramic plate, wherein, The ceramic plate includes: The upper layer has a first hole formed on its upper surface; The lower layer has a second hole formed on its lower surface, which is located in a different position in the horizontal direction than the first hole; and An intermediate layer, which is disposed between the upper layer and the lower layer. The intermediate layer has: An electrode layer formed of conductive components, said electrode layer being obtained by firing a slurry layer; and A flow path is formed inside the electrode layer, extending along the horizontal direction and connecting the first hole and the second hole. The electrode layer has the same thickness as the slurry layer after firing.

14. An electrostatic chuck, which is an electrostatic chuck having a ceramic plate, wherein, The ceramic plate includes: The upper layer has a first hole formed on its upper surface; The lower layer has a second hole formed on its lower surface, which is located in a different position in the horizontal direction than the first hole; and An intermediate layer, which is disposed between the upper layer and the lower layer. The intermediate layer is formed by firing a slurry layer. The intermediate layer has internal flow paths that extend horizontally and connect the first hole and the second hole. The thickness of the flow path is the thickness of the slurry layer after firing.

15. An electrostatic chuck, which is an electrostatic chuck having a ceramic plate, wherein, The ceramic plate includes: The upper layer has a first hole formed on its upper surface; The lower layer has a second hole formed on its lower surface, which is located in a different position in the horizontal direction than the first hole; and An intermediate layer, which is disposed between the upper layer and the lower layer. The intermediate layer has: A flow path extending along the horizontal direction and connecting the first hole and the second hole; and A porous layer, which is obtained by firing a slurry layer, connects the side of the ceramic plate with the flow path, which is formed inside the porous layer.

16. The electrostatic chuck according to any one of claims 13 to 15, wherein, The flow path includes a main flow path and a secondary flow path. The secondary flow path is connected to the main flow path and is narrower than the main flow path. The main flow path is connected to the second hole, and the secondary flow path is connected to the first hole.

17. The electrostatic chuck according to any one of claims 13 to 15, wherein, The opening of the first hole is smaller than the opening of the second hole.

18. A substrate processing apparatus, wherein, The substrate processing apparatus has: Handling containers; A stage, disposed within the processing container, for mounting a substrate; and The electrostatic chuck according to any one of claims 13 to 17 is disposed on the mounting stage.

19. The substrate processing apparatus according to claim 18, wherein, The second hole is configured to be connected to a gas source via a gas supply pipeline.

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