Electrostatic chuck and processing apparatus

Abstract

Provided is an electrostatic chuck capable of maintaining an arc discharge suppressing effect for a long period of time and a processing apparatus. An electrostatic chuck is provided with: a joint portion provided between a substrate and a base plate; a gas introduction path having a first hole portion provided in the substrate, a second hole portion provided in the base plate, and a third hole portion provided in the joint portion; a counterbore portion provided in at least either of the first hole portion and the second hole portion; and a porous portion having an exposed surface exposed to the third hole portion and provided in the counterbore portion, the porous portion having: a porous portion having gas permeability; and a denser portion denser than the porous portion, the denser portion being configured to cover the outer periphery of the porous portion, at least a portion of the denser portion constituting a first protruding portion protruding from the exposed surface in a first direction toward the third hole portion when the direction from the base plate toward the substrate is taken as the first direction.

Description

Technical Field

[0001] The present invention relates to an electrostatic chuck and a processing device. Background Technology

[0002] An electrostatic chuck comprising a ceramic dielectric substrate such as alumina and electrodes is used to apply an electrostatic adsorption current to the electrodes, thereby adsorbing substrates such as silicon wafers through electrostatic force. In such an electrostatic chuck, an inert gas such as helium (He) flows between the surface of the ceramic dielectric substrate and the back side of the substrate to be adsorbed, thereby controlling the temperature of the substrate.

[0003] For example, in apparatuses that process substrates, such as chemical vapor deposition (CVD) devices, sputtering devices, ion implantation devices, and etching devices, there are components that cause the substrate temperature to rise during processing. In electrostatic chucks used in such devices, an inert gas, such as he, flows between the ceramic dielectric substrate and the substrate to be adsorbed, thereby suppressing the temperature rise of the substrate by bringing the inert gas into contact with the substrate.

[0004] In an electrostatic chuck that controls the temperature of a substrate using an inert gas such as He, holes (gas introduction paths) for introducing the inert gas such as He are provided in a ceramic dielectric substrate and a base plate supporting the ceramic dielectric substrate. Furthermore, through holes communicating with the gas introduction path in the base plate are provided on the ceramic dielectric substrate. Thus, the inert gas introduced from the gas introduction path in the base plate is guided to the back side of the substrate through the through holes in the ceramic dielectric substrate.

[0005] Here, when processing a substrate within the device, discharges (arc discharges) sometimes occur from plasma within the device toward a metal base plate. The gas inlet path of the base plate and the through-holes of the ceramic dielectric substrate can easily become discharge paths. Therefore, there are techniques that improve resistance to arc discharges (insulation strength, etc.) by providing porous portions in the gas inlet path of the base plate or the through-holes of the ceramic dielectric substrate. For example, Patent Document 1 discloses an electrostatic chuck that improves insulation within the gas inlet path by providing a sintered ceramic porous body within the gas inlet path, using the structure and pores of the sintered ceramic porous body as a gas flow path. Furthermore, Patent Document 2 discloses an electrostatic chuck in which a ceramic porous body is disposed in the gas inlet path of the base plate and the through-holes of the ceramic dielectric substrate. In addition, Patent Document 3 describes a technique in which a porous ceramic body is disposed in the gas inlet path of the base plate or the through hole of the ceramic dielectric substrate, and a protective material is disposed in the part of the adhesive layer that bonds the base plate and the ceramic dielectric substrate that is exposed to the gas inlet path and / or through hole, thereby inhibiting the corrosion of the adhesive.

[0006] In such electrostatic chucks, it is required to maintain the suppression effect of arc discharge for a long time.

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2010-123712

[0009] Patent Document 2: US Patent No. US2017 / 0352568

[0010] Patent Document 3: Japanese Patent Application Publication No. 2021-057468 Summary of the Invention

[0011] This invention is based on the understanding of such a problem, and the technical problem to be solved is to provide an electrostatic chuck and processing device that can maintain the suppression effect of arc discharge for a long time.

[0012] The first invention is an electrostatic chuck, comprising: a ceramic dielectric substrate having a first main surface for placing an object to be adsorbed and a second main surface opposite to the first main surface; a base plate supporting the ceramic dielectric substrate, having an upper surface on the side of the ceramic dielectric substrate and a lower surface opposite to the upper surface; a joint portion disposed between the ceramic dielectric substrate and the base plate; a gas inlet passage passing through the ceramic dielectric substrate, the base plate, and the joint portion, having a first hole in the ceramic dielectric substrate, a second hole in the base plate, and a third hole in the joint portion; and a countersinking portion disposed in the first... The document describes a cavity portion and at least one of the second cavity portion; and a ceramic porous portion having an exposed surface exposed to the third cavity portion and disposed in the countersunk portion, characterized in that, when a direction from the base plate toward the ceramic dielectric substrate is taken as a first direction and a direction substantially orthogonal to the first direction is taken as a second direction, the ceramic porous portion has: a porous portion with air permeability; and a dense portion that is denser than the porous portion, the dense portion being configured to cover the outer periphery of the porous portion, at least a portion of the dense portion constituting a first protrusion protruding from the exposed surface along the first direction toward the third cavity portion.

[0013] In this electrostatic chuck, a porous ceramic portion is disposed in the gas inlet path, and at least a portion of the dense portion forms a first protrusion protruding from the exposed surface along a first direction toward the third hole. This suppresses breakdown. Furthermore, when using the electrostatic chuck, the portion of the joint 60 exposed toward the third hole may be corroded by plasma, generating particles. The first protrusion provided in the porous ceramic portion acts as a physical barrier layer, suppressing the intrusion of particles generated by plasma corrosion into the porous portion. Thus, the arc discharge suppression effect can be maintained for a long period.

[0014] The second invention is an electrostatic chuck, characterized in that, in the first invention, the length of the first protrusion from the exposed surface along the first direction is approximately the same as the length of the joint along the first direction.

[0015] This electrostatic chuck can further improve resistance to puncture. In addition, it can more effectively suppress particle intrusion and maintain the suppression effect of arc discharge for a long time.

[0016] The third invention is an electrostatic chuck, characterized in that, in the first or second invention, the countersink is disposed in the first hole.

[0017] According to this electrostatic chuck, by placing the porous ceramic portion in the first pore, which is closer to the plasma, the puncture resistance can be further improved. Furthermore, because of the first protrusion, although the porous ceramic portion in the first pore is located further downstream in the gas flow than the third pore, which could potentially become a particle generation point, particle intrusion into the porous ceramic portion can be more effectively suppressed, thus maintaining the arc discharge suppression effect for a longer period.

[0018] The fourth invention is an electrostatic chuck, characterized in that, in the third invention, the first hole portion has: a first part opening toward the first main surface; a second part opening toward the second main surface; and an intermediate part disposed between the first part and the second part, the countersunk portion being disposed in the second part, the length of the intermediate part along the second direction being greater than the length of the first part along the second direction, and the ceramic porous portion having a surface opposite to the exposed surface, the surface being configured to expose toward the intermediate part.

[0019] According to this electrostatic chuck, a countersunk portion is provided in the first hole portion, and the surface opposite to the exposed surface of the ceramic porous portion in the countersunk portion, i.e., the surface on the first main surface side, is exposed towards the middle portion of the first hole portion. Since the width (length along the second direction) of the middle portion is greater than the width of the first portion, a space corresponding to the middle portion is provided between the surface on the first main surface side of the ceramic porous portion and the first portion. Therefore, the gas flow rate can be more reliably ensured.

[0020] The fifth invention is an electrostatic chuck, characterized in that, in the fourth invention, the dense portion further has a second protrusion protruding from the surface along the first direction toward the first portion.

[0021] This electrostatic chuck can further improve puncture resistance.

[0022] The sixth invention is an electrostatic chuck, comprising: a ceramic dielectric substrate having a first main surface for placing an object to be adsorbed and a second main surface opposite to the first main surface; a base plate supporting the ceramic dielectric substrate, having an upper surface on the side of the ceramic dielectric substrate and a lower surface opposite to the upper surface; a joint portion disposed between the ceramic dielectric substrate and the base plate; a gas inlet passage passing through the ceramic dielectric substrate, the base plate, and the joint portion, having a first hole in the ceramic dielectric substrate, a second hole in the base plate, and a third hole in the joint portion; and a countersinking portion disposed in the second... A porous portion; and a ceramic porous portion having an exposed surface exposed to the third porous portion and disposed in the countersunk portion, characterized in that, when a direction from the base plate toward the ceramic dielectric substrate is taken as a first direction and a direction substantially orthogonal to the first direction is taken as a second direction, the ceramic porous portion has: a porous portion with air permeability; and a dense portion that is denser than the porous portion, the dense portion being configured to cover the outer periphery of the porous portion, at least a portion of the dense portion forming a first protrusion protruding from the exposed surface along the first direction toward the third porous portion, the first porous portion comprising a plurality of fine pores.

[0023] In this electrostatic chuck, a porous ceramic portion is disposed in the second hole portion of the gas inlet path, and a dense portion is provided to cover the outer periphery of the porous portion. At least a portion of this dense portion constitutes a first protrusion extending from the exposed surface to the third hole portion along a first direction. Furthermore, the first hole portion is composed of multiple fine pores. Therefore, breakdown can be suppressed. Additionally, when using the electrostatic chuck, the portion of the joint exposed to the third hole portion may be corroded by plasma, generating particles. The first protrusion portion acts as a physical barrier layer, preventing particles generated by plasma corrosion from penetrating the porous ceramic portion and the multiple fine pores (first hole portion) located downstream of the third hole portion. Thus, the arc discharge suppression effect can be maintained for a long period.

[0024] The seventh invention is a processing apparatus, characterized by comprising: any one of the aforementioned electrostatic chucks; and a supply unit capable of supplying gas to a gas inlet path disposed on the electrostatic chucks. According to this processing apparatus, the arc discharge suppression effect can be maintained for a long period.

[0025] According to the present invention, an electrostatic chuck and processing device are provided that can maintain the suppression effect of arc discharge for a long time. Attached Figure Description

[0026] Figure 1 This is a schematic cross-sectional view illustrating the electrostatic chuck involved in this embodiment.

[0027] Figure 2 (a) and (b) are schematic diagrams illustrating the electrostatic chucks involved in the embodiments.

[0028] Figure 3 This is a schematic diagram illustrating the electrostatic chuck involved in the embodiment.

[0029] Figure 4 This is a schematic cross-sectional view illustrating an electrostatic chuck according to other embodiments.

[0030] Figure 5 This is a schematic cross-sectional view illustrating an electrostatic chuck according to other embodiments.

[0031] Figure 6 This is a schematic diagram illustrating the processing apparatus involved in this embodiment.

[0032] Figure 7 This is a schematic cross-sectional view of the electrostatic chuck involved in the illustrative embodiment.

[0033] Figure 8 This is a schematic diagram illustrating the processing apparatus involved in the embodiment.

[0034] Figure 9 This is a schematic cross-sectional view of the electrostatic chuck involved in the illustrative embodiment.

[0035] Symbol Explanation

[0036] 11-Ceramic dielectric substrate; 11a-First main surface; 11b-Second main surface; 12-Electrode; 13-Point; 14-Groove; 16-Fine hole; 20-Connection part; 3a-First protrusion; h1-Protrusion length (height); 3b-Second protrusion; 50-Base plate; 50a-Upper part; 50b-Lower part; 50u-Top part; 50d-Bottom part; 51-Input path; 52-Output path; 53-Gas introduction path; 53a- 1st hole; 53aa - Part 1; t1a - Length (width); 53ab - Part 2; 53ac - Middle part; 53ah - Countersunk surface; 53as - Inner peripheral side; t1c - Length (width); t4a - Length; 53b - 2nd hole; 53bu - Part 3; 53bd - Part 4; t2b - Length (width); 53c - 3rd hole; tc - Length (width); 53s - Countersunk portion; ts, tsa, tsb - Length (width); 55 - Connecting path; 60 - Joint; 60e - End; h2 - Length (height); 70 - Ceramic porous portion (porous portion); 70a - Third surface; 70b - Fourth surface; 71 - Second porous portion; 73 - Second dense portion; 73c - Second central dense portion; t2 - Length (width); 90 - Ceramic porous portion (porous portion); 90a - First surface; 90b - ... 2 sides; 91-First porous section; 93-First dense section; 93c-First central dense section; t1-Length (width); 110-Electrostatic chuck; 200-Processing device; 210-Power supply; 211-Wiring; 220-Media supply section; 221-Receiving section; 222-Control valve; 223-Discharge section; 230-Supply section; 231-Gas supply section; 232-Gas control section; 240-Cavity; W-Object. Detailed Implementation

[0037] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, in each drawing, the same reference numerals are used to denote the same constituent elements, and detailed descriptions are omitted where appropriate.

[0038] Furthermore, in each of the accompanying drawings, the direction from the base plate 50 toward the ceramic dielectric substrate 11 is designated as the Z direction (corresponding to an example of the first direction), one of the directions that is approximately orthogonal to the Z direction is designated as the Y direction (corresponding to an example of the second direction), and the direction that is approximately orthogonal to both the Z and Y directions is designated as the X direction (corresponding to an example of the second direction).

[0039] electrostatic chuck

[0040] Figure 1 This is a schematic cross-sectional view illustrating the electrostatic chuck involved in this embodiment.

[0041] like Figure 1As shown, the electrostatic chuck 110 according to this embodiment includes a ceramic dielectric substrate 11, a base plate 50, and a porous portion 90. In this example, the electrostatic chuck 110 also includes a porous portion 70.

[0042] The ceramic dielectric substrate 11 is, for example, a flat substrate material formed from sintered ceramic. For example, the ceramic dielectric substrate 11 contains alumina (Al₂O₃). For example, the ceramic dielectric substrate 11 is formed from high-purity alumina. The concentration of alumina in the ceramic dielectric substrate 11 is, for example, 99 atomic% or more and 100 atomic% or less. By using high-purity alumina, the plasma resistance of the ceramic dielectric substrate 11 can be improved. The ceramic dielectric substrate 11 has: a first main surface 11a on which an object W (adsorbed object) is placed; and a second main surface 11b opposite to the first main surface 11a. The object W is, for example, a semiconductor substrate such as a silicon wafer.

[0043] An electrode 12 is disposed in a ceramic dielectric substrate 11. The electrode 12 is disposed between the first main surface 11a and the second main surface 11b of the ceramic dielectric substrate 11. The electrode 12 is formed by being inserted into the ceramic dielectric substrate 11. A power supply 210 is electrically connected to the electrode 12 via a connection portion 20 and a wiring 211. By applying an adsorption and holding voltage to the electrode 12 using the power supply 210, a charge is generated on the first main surface 11a side of the electrode 12, enabling the object W to be adsorbed and held using electrostatic force.

[0044] The electrode 12 is shaped like a thin film extending along the first main surface 11a and the second main surface 11b of the ceramic dielectric substrate 11. The electrode 12 is an adsorption electrode used to adsorb and hold the object W. The electrode 12 can be either unipolar or bipolar. Figure 1 The illustrated electrode 12 is bipolar, with two electrodes disposed on the same surface. In addition to the electrode 12, electrodes for high-frequency external application or heater electrodes may also be disposed in the ceramic dielectric substrate 11.

[0045] The electrode 12 is provided with a connecting portion 20 extending toward the second main surface 11b of the ceramic dielectric substrate 11. The connecting portion 20 is, for example, a via (solid type) or a via hole (hollow type) that communicates with the electrode 12. The connecting portion 20 can also be a metal terminal that is connected by a suitable method such as brazing.

[0046] The base plate 50 is a component that supports the ceramic dielectric substrate 11. The base plate 50 has a top surface 50u on the side of the ceramic dielectric substrate 11 and a bottom surface 50d on the opposite side of the top surface 50u. The ceramic dielectric substrate 11 is supported by... Figure 2(a) The illustrated joint 60 is fixed to the base plate 50. For example, the joint 60 is a portion in which silicone adhesive can be cured. In this example, the joint 60 is configured to contact the upper surface 50u of the base plate 50 and the second main surface 11b of the ceramic dielectric substrate 11.

[0047] The base plate 50 is, for example, made of metal. The base plate 50 is, for example, divided into an upper part 50a and a lower part 50b made of aluminum, with a connecting passage 55 provided between the upper part 50a and the lower part 50b. One end of the connecting passage 55 is connected to an input passage 51, and the other end of the connecting passage 55 is connected to an output passage 52. The end of the base plate 50 on the second main surface 11b side may also have a spray-plated portion (not shown). The spray-plated portion is formed, for example, by spray plating. The spray-plated portion may also form the end face (upper surface 50u) on the second main surface 11b side of the base plate 50. The spray-plated portion is provided as needed and may be omitted.

[0048] The base plate 50 also functions as a temperature regulator for the electrostatic chuck 110. For example, when cooling the electrostatic chuck 110, a cooling medium flows in from the input path 51 and out from the output path 52 through the connecting path 55. Thus, by absorbing heat from the base plate 50 through the cooling medium, the ceramic dielectric substrate 11 mounted thereon can be cooled. On the other hand, when heat preservation is needed for the electrostatic chuck 110, a heat preservation medium can be placed in the connecting path 55. A heating element can also be placed inside the ceramic dielectric substrate 11 or the base plate 50. By adjusting the temperature of the base plate 50 or the ceramic dielectric substrate 11, the temperature of the object W held and held by the electrostatic chuck 110 can be adjusted.

[0049] Furthermore, on the first main surface 11a side of the ceramic dielectric substrate 11, dots 13 are provided as needed, and grooves 14 are provided between the dots 13. That is, the first main surface 11a is a concave-convex surface, having concave portions and convex portions. The convex portions of the first main surface 11a correspond to the dots 13, and the concave portions of the first main surface 11a correspond to the grooves 14. The grooves 14 can, for example, extend continuously in the XY plane. As a result, gases such as He can be distributed throughout the first main surface 11a. A space is formed between the back side of the object W placed on the electrostatic chuck 110 and the first main surface 11a containing the grooves 14.

[0050] By appropriately selecting the height of point 13, the depth of groove 14, and the area ratio and shape of point 13 to groove 14, the temperature of object W and the particles attached to object W can be controlled in an optimal state.

[0051] The gas introduction path 53 is provided to pass through the ceramic dielectric substrate 11, the base plate 50, and the junction 60. The gas introduction path 53 has a first hole 53a located in the ceramic dielectric substrate 11, a second hole 53b located in the base plate 50, and a third hole 53c located in the junction 60. The second hole 53b is provided to, for example, pass through the base plate 50. The second hole 53b can pass through the base plate 50 in a straight line or branch off along the way. The gas introduction path 53 is provided at multiple locations on the base plate 50.

[0052] The first hole 53a is connected to the groove 14, for example. The first hole 53a is provided across the span from the second main surface 11b to the first main surface 11a. That is, the first hole 53a extends in the Z direction from the second main surface 11b to the first main surface 11a and passes through the ceramic dielectric substrate 11.

[0053] The second orifice 53b is connected to the first orifice 53a via the third orifice 53c. Gas (such as helium (He)) flowing into the second orifice 53b passes through the third orifice 53c after passing through the second orifice 53b, and then flows into the first orifice 53a.

[0054] Gas flowing into the first orifice 53a flows into the space between the object W and the first main surface 11a containing the groove 14 after passing through the first orifice 53a. Thus, the object W can be directly cooled by gas.

[0055] A countersunk portion 53s is provided in at least one of the first hole portion 53a and the second hole portion 53b. A porous portion 90 and / or a porous portion 70 are disposed in the countersunk portion 53s.

[0056] The first hole portion 53a has: a first portion 53aa including a first main surface 11a; and a second portion 53ab including a second main surface 11b. Other portions (e.g., the intermediate portion 53ac described later) may also be present between the first portion 53aa and the second portion 53ab. The countersink portion 53s is provided, for example, in the second portion 53ab.

[0057] The second hole portion 53b has a third portion 53bu that includes the upper part 50u, and a fourth portion 53bd that includes the lower part 50d. Other portions may also be present between the third portion 53bu and the fourth portion 53bd. For example, the countersink portion 53s may be provided in the third portion 53bu.

[0058] Porous portions 90 and / or 70 are disposed in the counterbored portion 53s. The porous portion 90 has an exposed surface that extends into the third hole portion 53c, namely a first surface 90a and a second surface 90b opposite to the first surface 90a. The porous portion 70 has an exposed surface that extends into the third hole portion 53c, namely a third surface 70a and a fourth surface 70b opposite to the third surface 70a. In this specification, the porous portion 90 is used when disposed inside the ceramic dielectric substrate 11 (first hole portion 53a), and the porous portion 70 is used when disposed inside the base plate 50 (second hole portion 53b).

[0059] In the gas inlet path 53, cooling gas such as helium flows in the order of the second hole 53b, the third hole 53c, and the first hole 53a, and is supplied to the first main surface 11a side of the ceramic dielectric substrate 11, for example, via the groove 14. When an electrostatic chuck is used, the plasma is located on the first main surface 11a side. Therefore, when the ceramic porous portion 90 is disposed in the first hole 53a and the ceramic porous portion 70 is disposed in the second hole 53b, it is preferable that the ceramic porous portion 90 disposed closer to the plasma has a higher puncture resistance than the ceramic porous portion 70. As an example, the pore size of the first porous portion 91 of the porous portion 90 (described in detail later) is made smaller than that of the second porous portion 71 of the porous portion 70, and the porosity of the first porous portion 91 is made smaller than that of the second porous portion 71. At this point, since the permeability of the porous portion 70 located on the upstream side of the gas flow is higher than that of the porous portion 90 located on the downstream side of the gas flow, it should also be preferred from the viewpoint of gas flow control.

[0060] Figure 2 (a), (b) and Figure 3 This is a schematic diagram illustrating the electrostatic chuck involved in the embodiment.

[0061] Figure 2 and Figure 3 This is a schematic cross-sectional view illustrating the periphery of the porous portion 90 and the porous portion 70, equivalent to... Figure 1 An enlarged view of region A shown. Figure 2 (b) is Figure 2 (a) is an enlarged view of the area shown.

[0062] Furthermore, in order to avoid becoming complicated, Figure 2 Point 13 is omitted (for example, refer to...) Figure 1 It was described in this way.

[0063] like Figure 2As shown, in this example, a porous portion 90 is disposed in the countersunk portion 53s provided in the first hole portion 53a, and a porous portion 70 is disposed in the countersunk portion 53s provided in the second hole portion 53b. The first surface 90a of the porous portion 90 is an exposed surface that exposes to the third hole portion 53c. The first surface 90a and the second main surface 11b of the ceramic dielectric substrate 11 are located on approximately the same plane. The third surface 70a of the porous portion 70 is an exposed surface that exposes to the third hole portion 53c. The third surface 70a and the upper surface 50u of the base plate 50 are located on approximately the same plane.

[0064] In this example, the length ts of the countersunk portion 53s in the first hole portion 53a along the X or Y direction is the same as or less than the length tc of the third hole portion 53c along the X or Y direction. The length t1 of the porous portion 90 along the X or Y direction is the same as or less than the length ts. Therefore, the breakdown suppression effect can be improved.

[0065] If the width (length t1) of the porous portion 90 is the same as the width (length ts) of the countersunk portion 53s, then discharge between the side surfaces of the porous portion 90 (the surfaces perpendicular to the first surface 90a and the second surface 90b, respectively) and the countersunk portion 53s can be suppressed. For example, by sintering, the ceramic dielectric substrate 11 and the porous portion 90 can be integrated, thereby making the length t1 and the length ts the same.

[0066] Reference Figure 2 Further explanation is needed.

[0067] In this example, a porous portion 90 is provided in the first hole portion 53a and a porous portion 70 is provided in the second hole portion 53b. The porous portion 90 has a first protrusion 3a.

[0068] The porous portion 90 has a first porous portion 91 and a first dense portion 93. The first porous portion 91 is permeable to air. The first dense portion 93 is denser than the first porous portion 91. The porosity of the first porous portion 91 is greater than that of the first dense portion 93. The first porous portion 91 has a plurality of pores. Preferably, the plurality of pores are straight pores with a pore diameter within a defined range. In this case, the pore diameter is, for example, 1 μm to 30 μm. The plurality of pores can also be randomly arranged while being interconnected. The first dense portion 93 may also be substantially non-permeable to air. The first dense portion 93 is configured to cover the outer periphery of the first porous portion 91. By providing the first dense portion 93, the rigidity of the porous portion 90 can be improved. For example, when an adhesive is placed between the side surface of the porous portion 90 (the surface perpendicular to the first surface 90a and the second surface 90b, respectively) and the countersunk portion 53s, the presence of the first dense portion 93 can prevent the adhesive from penetrating the porous portion 90 and causing poor air permeability.

[0069] In this example, the porous portion 70 also has a second porous portion 71 and a second dense portion 73. The second porous portion 71 is permeable to air. The second dense portion 73 is denser than the second porous portion 71. The porosity of the second porous portion 71 is greater than that of the second dense portion 73. The second dense portion 73 may also be substantially non-permeable to air. The second dense portion 73 is configured to cover the outer periphery of the second porous portion 71. Furthermore, in the second porous portion 71, when the plurality of holes are linear holes with a pore diameter within a defined range, its pore diameter may be larger than that of the first porous portion 91.

[0070] For example, the density of the first porous portion 91 is lower than the density of the first dense portion 93. For example, the air permeability of the first porous portion 91 is higher than that of the first dense portion 93. For example, the first porous portion 91 is cylindrical. The first dense portion 93 contacts the outer peripheral side of the first porous portion 91. The first dense portion 93 is annular (tubular) surrounding the outer peripheral side of the first porous portion 91.

[0071] For example, the density of the second porous portion 71 is lower than the density of the second dense portion 73. For example, the air permeability of the second porous portion 71 is higher than that of the second dense portion 73. For example, the second porous portion 71 is cylindrical. The second dense portion 73 contacts the outer peripheral side of the second porous portion 71. The second dense portion 73 is annular (tubular) surrounding the outer peripheral side of the second porous portion 71.

[0072] like Figure 2 As shown, in the porous portion 90, at least a portion of the first dense portion 93 forms a first protrusion 3a that protrudes from the exposed surface, i.e., the first surface 90a, along the Z direction toward the third hole portion 53c. Here, the first surface 90a is the surface in the porous portion 90 that forms the largest area on the side of the third hole portion 53c. In this example, the first porous portion 91 forms the first surface 90a.

[0073] That is, for example, the first surface 90a is the lower surface of the first porous portion 91. For example, the first protrusion 3a is the portion of the first dense portion 93 that protrudes downward from the first surface 90a (in the direction from the ceramic dielectric substrate 11 toward the base plate 50). At this time, the first protrusion 3a is the portion of the first dense portion 93 located closer to the lower surface than the first surface 90a. The planar shape of the first protrusion 3a in the XY plane is, for example, annular.

[0074] In the electrostatic chuck 110, a porous ceramic portion 90 is disposed in, for example, the first hole 53a of the gas inlet path 53. At least a portion of the first dense portion 93 of the porous portion 90 constitutes a first protrusion 3a protruding in the Z direction from the exposed surface (first surface 90a) of the third hole 53c side of the porous portion 90. Therefore, breakdown can be suppressed. In addition, when the electrostatic chuck is used, the end 60e of the joint 60 exposed to the third hole 53c may be corroded by plasma, generating particles. Even in this case, the first protrusion 3a provided in the porous ceramic portion 90 acts as a physical barrier layer, which can suppress the intrusion of particles generated by plasma corrosion into the first porous portion 91 of the porous portion 90 or the second porous portion 71 of the porous portion 70. Thus, the arc discharge suppression effect can be maintained for a long time.

[0075] In this example, the first protrusion 3a contacts the third surface 70a of the porous portion 70. When the second hole portion 53b is not provided with a countersunk portion 53s, that is, when the porous portion 70 is not present, the first protrusion 3a contacts the upper surface 50u of the base plate 50.

[0076] In this example, the length h1 of the first protrusion 3a from the exposed portion (first surface 90a) along the Z direction is approximately the same as the length h2 of the joint 60 along the Z direction. Therefore, the puncture resistance can be further improved. Furthermore, particle intrusion can be more effectively suppressed, and the arc discharge suppression effect can be maintained for a longer period. In this example, the tip of the first protrusion 3a contacts the third surface 70a of the porous portion 70. When the first protrusion 3a is annular and its tip contacts the third surface 70a, the gas flow can be physically cut off from the end 60e of the joint 60, thus effectively suppressing particle intrusion into the porous portion 90 and / or the porous portion 70, and preventing particle blockage of the porous portion and the time-dependent decrease in flow rate.

[0077] For example, when viewed in the X or Y direction, if the first surface 90a overlaps with the joint 60, the protrusion length h1 of the first protrusion 3a can be made smaller than the length h2 of the joint 60 in the Z direction.

[0078] That is, in the second direction, when the first surface 90a and the joint 60 are aligned (overlapping), the protruding length h1 can be less than the length h2. Furthermore, in Figure 2 In example (b), the protrusion length h1 is the distance between the Z-direction position of the first surface 90a and the Z-direction position of the lower end of the first protrusion 3a.

[0079] In this example, besides the first portion 53aa opening to the first main surface 11a and the second portion 53ab opening to the second main surface 11b, the first hole portion 53a also has an intermediate portion 53ac disposed between the first portion 53aa and the second portion 53ab. A countersunk portion 53s is disposed in the second portion 53ab. In this example, the first portion 53aa opens into the groove 14 disposed on the first main surface 11a. The intermediate portion 53ac is located between the second surface 90b and the first portion 53aa of the porous portion 90. The surface opposite to the exposed surface (first surface 90a) of the porous portion 90, namely the second surface 90b, exposes to the intermediate portion 53ac. The length t1c of the intermediate portion 53ac in the X or Y direction is configured to be greater than the length t1a of the first portion 53aa in the X or Y direction.

[0080] When using an electrostatic chuck, the second surface 90b of the porous portion 90 is directly exposed to plasma through the first aperture 53a. Therefore, the porous portion 90 is required to have higher puncture resistance than the porous portion 70, and as mentioned above, its permeability is sometimes set to be lower than that of the porous portion 70. By providing the intermediate portion 53ac, permeability can be improved, and a certain gas flow rate can be easily obtained.

[0081] In this example, the first dense portion 93 also has a second protrusion 3b that protrudes from the second surface 90b along the Z direction toward the first portion 53aa. This further improves the resistance to penetration.

[0082] That is, for example, the second surface 90b is the upper surface of the first porous portion 91. For example, the second protrusion 3b is the portion of the first dense portion 93 that protrudes upward from the second surface 90b (in the direction from the base plate 50 toward the ceramic dielectric substrate 11). At this time, the second protrusion 3b is the portion of the first dense portion 93 located closer to the upper surface than the second surface 90b. The planar shape of the second protrusion 3b in the XY plane is, for example, annular.

[0083] Next, refer to Figure 3 Please provide an explanation.

[0084] In this example, a porous portion 90 is provided in the first hole portion 53a and a porous portion 70 is provided in the second hole portion 53b, and the porous portion 70 has a first protrusion 3a.

[0085] like Figure 3 As shown, in this example, in the porous portion 70, at least a portion of the second dense portion 73 forms a first protrusion 3a protruding from the exposed surface, i.e., the third surface 70a, along the Z direction toward the third hole portion 53c. Here, the third surface 70a is the surface in the porous portion 70 that forms the largest area on the side of the third hole portion 53c. In this example, the second porous portion 71 forms the third surface 70a.

[0086] That is, for example, the third surface 70a is the upper surface of the second porous portion 71. For example, the first protrusion 3a is the portion in the second dense portion 73 that protrudes upward from the third surface 70a. In this case, the first protrusion 3a is the portion in the second dense portion 73 that is located closer to the top than the third surface 70a.

[0087] In the electrostatic chuck 110, a porous ceramic portion 70 is disposed in, for example, the second hole 53b of the gas inlet path 53. At least a portion of the second dense portion 73 of the porous portion 70 constitutes a first protrusion 3a protruding in the Z direction from the exposed surface (third surface 70a) of the porous portion 70 from the side of the third hole 53c. Therefore, breakdown can be suppressed. In addition, when the electrostatic chuck is used, the end 60e of the joint 60 exposed to the third hole 53c may be corroded by plasma, generating particles. Even in this case, the first protrusion 3a provided in the porous ceramic portion 70 acts as a physical barrier layer, which can suppress the intrusion of particles generated by plasma corrosion into the first porous portion 91 or the second porous portion 71 of the porous portion 90. Thus, the arc discharge suppression effect can be maintained for a long time.

[0088] In this example, the first protrusion 3a contacts the first surface 90a of the porous portion 90 and the second main surface 11b of the ceramic dielectric substrate 11. When the first hole portion 53a is not provided with a countersunk portion 53s, that is, when the porous portion 90 is not provided, the first protrusion 3a contacts the second main surface 11b of the ceramic dielectric substrate 11.

[0089] In this example, the length h1 of the first protrusion 3a from the exposed portion (third surface 70a) along the Z direction is approximately the same as the length h2 of the joint 60 along the Z direction. Therefore, the puncture resistance can be further improved. Furthermore, particle intrusion can be more effectively suppressed, and the arc discharge suppression effect can be maintained for a longer period. In this example, the tip of the first protrusion 3a contacts the first surface 90a of the porous portion 90. When the first protrusion 3a is annular and its tip contacts the first surface 90a, the gas flow can be physically cut off from the end 60e of the joint 60, thus effectively suppressing particle intrusion into the porous portion 90 and / or the porous portion 70, and preventing particle blockage of the porous portion and the time-dependent decrease in flow rate.

[0090] For example, when viewed in the X or Y direction, if the first surface 90a overlaps with the joint 60, the protrusion length h1 of the first protrusion 3a can be made smaller than the length h2 of the joint 60 in the Z direction.

[0091] For example, in the second direction, when the third surface 70a is aligned (overlapping) with the joint 60, the protruding length h1 can be less than the length h2. Furthermore, in Figure 3 In the example, the protrusion length h1 is the distance between the Z-direction position of the third surface 70a and the Z-direction position of the upper end of the first protrusion 3a.

[0092] An insulating breakdown suppression section (not shown) can also be provided in the third pore portion 53c. By substantially filling the space of the third pore portion 53c with the breakdown suppression section, the breakdown resistance can be improved. The breakdown suppression section is configured to allow gas to pass through. The breakdown suppression section can also be elastic. The breakdown suppression section can also be made of fluoropolymers such as polyimide and polytetrafluoroethylene (PTFE), or resins such as epoxy. The breakdown suppression section can also be made of ceramic. Preferably, the air permeability of the breakdown suppression section is higher than that of the porous portion 90.

[0093] The porosity of the porous portion 90 can be less than that of the porous portion 70. In the gas introduction path 53, by making the porosity of the porous portion 90, which is disposed closer to the plasma atmosphere, relatively small, the breakdown resistance can be further improved. The porosity of the breakdown suppression portion can be greater than that of the porous portion 90. The porosity of the breakdown suppression portion can be greater than that of the porous portion 70.

[0094] Although Figure 2 and Figure 3 An example of an electrostatic chuck with two porous parts (porous part 90 and porous part 70) is described, but it is not limited to this. It can be changed according to the purpose, and it can also have only one porous part (porous part 90 or porous part 70).

[0095] As an example, the transverse width (ts) of the countersunk portion 53s is 1 mm to 5 mm. In the first hole portion 53a, the length t1a of the first part 53aa along the X or Y direction is, for example, 0.05 mm or more and 0.5 mm or less.

[0096] Furthermore, when the first portion 53aa of the first hole 53aa opens into the groove 14, the width (t1a) of the first portion 53aa is the width of the portion of the first portion 53aa that contacts the groove. The widths (t1) of the porous portion 90 and (t2) of the porous portion 70 are both the dimensions of the largest portion. Preferably, more than 50% of the porous portion has this dimension, more preferably more than 70%, and even more preferably more than 90%.

[0097] The height (h2) of the joint 60 is, for example, 100 μm to 1000 μm, preferably 200 μm to 600 μm. Furthermore, the length of the joint 60 in the Z direction is the same as the length of the third hole 53c in the Z direction.

[0098] In this example, the second surface 90b of the porous portion 90 is located inside the first hole portion 53a. That is, the second surface 90b and the first main surface 11a of the ceramic dielectric substrate 11 do not form the same plane. The fourth surface 70b of the porous portion 70 is located inside the second hole portion 53b. That is, the fourth surface 70b and the lower surface 50d of the base plate 50 do not form the same plane.

[0099] The porous portions 90 and 70 are made of insulating ceramic. The porous portion 90 (the respective first porous portion 91 and first dense portion 93 described later) contains at least one of alumina (Al₂O₃), titanium oxide (TiO₂), and yttrium oxide (Y₂O₃). This results in higher insulation strength and higher rigidity of the porous portion 90.

[0100] For example, the porous part 90 may use any one of alumina, titanium dioxide, and yttrium oxide as the main component.

[0101] At this point, the purity of the alumina in the ceramic dielectric substrate 11 can be higher than the purity of the alumina in the porous portion 90. This ensures the plasma resistance and other properties of the electrostatic chuck 110, and also ensures the mechanical strength of the porous portion 90. As an example, by including trace amounts of additives in the porous portion 90, the sintering of the porous portion 90 is promoted, ensuring control of porosity and mechanical strength.

[0102] The details of the porous portion 90 and the porous portion 70 are incorporated herein by reference as part of this specification.

[0103] This specification allows for the determination of the ceramic purity of alumina and other materials in the ceramic dielectric substrate 11 using methods such as fluorescence X-ray analysis and ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry).

[0104] In porous portions, for example, the material of the porous portions (first porous portion 91, second porous portion 71) is the same as the material of the dense portions (first dense portion 93, second dense portion 73). However, the materials of the porous portions and the dense portions can also be different. Furthermore, the composition of the material in the porous portions can differ from the composition of the material in the dense portions.

[0105] Figure 4 This is a schematic diagram illustrating an electrostatic chuck according to other embodiments.

[0106] In this embodiment, the following configuration will be described: in the porous portion, when viewed in the Z direction, other dense portions are provided in the portion that overlaps with the gas inlet path 53 (first hole portion 53a).

[0107] like Figure 4 As shown, for example, in the porous portion 90, in addition to the first dense portion 93 arranged to cover the outer periphery of the first porous portion 91, a first central dense portion 93c is preferably provided at the portion of the first porous portion 91 that overlaps with the first portion 53aa of the first pore portion 53a in the Z direction. The first central dense portion 93c is denser than the first porous portion 91. The porosity of the first porous portion 91 is greater than that of the first central dense portion 93c. For example, the density of the first porous portion 91 is lower than that of the first central dense portion 93c. The air permeability of the first porous portion 91 is higher than that of the first central dense portion 93c. For example, the first central dense portion 93c is cylindrical. In this case, the first porous portion 91 contacts the outer peripheral side of the first central dense portion 93c, forming an annular (tubular) shape surrounding the first central dense portion 93c. Since the generated current must detour through the first central compact section 93c to flow, the path of current flow, i.e., the conductive busbar, can be lengthened. Therefore, electrons are difficult to accelerate, which can suppress the occurrence of arc discharge.

[0108] From the viewpoint of arc discharge suppression, it is preferable that the permittivity of at least one of the first dense portion 93 and the first central dense portion 93c is lower than the permittivity of the first porous portion 91. By reducing the permittivity of these dense portions, when using an electrostatic chuck, the potential difference involved other than the porous portion 90 can be reduced to suppress insulation failure.

[0109] Next, we will explain the case where other dense portions are provided in the porous portion 70.

[0110] For example, in the porous portion 70, in addition to the second dense portion 73 arranged to cover the outer periphery of the second porous portion 71, other dense portions may be provided. As an example of another dense portion, a second central dense portion 73c may be provided in the portion of the second porous portion 71 that overlaps with the first portion 53aa of the first pore portion 53a in the Z direction. In this case, for example, the second central dense portion 73c is cylindrical. Other examples include... Figure 4As shown, a second central dense portion 73c may be provided in the second porous portion 71 at a position opposite to the current flowing through the first central dense portion 93c. In this case, for example, a cylindrical porous portion (central porous portion) identical to the second porous portion 71 may be disposed inside the second central dense portion 73c. ​​The porosity, density, and air permeability of the central porous portion may also be the same as those of the second porous portion 71. The second central dense portion 73c is denser than the second porous portion 71. The porosity of the second porous portion 71 is greater than that of the second central dense portion 73c. ​​For example, the density of the second porous portion 71 is lower than that of the second central dense portion 73c. ​​The air permeability of the second porous portion 71 is higher than that of the second central dense portion 73c. ​​The second central dense portion 73c may also be in annular (tubular) shape, surrounding the outer peripheral surface of the central porous portion, in contact with the outer peripheral surface of the central porous portion. When the second central dense portion 73c is provided, the second porous portion 71 contacts the outer peripheral side of the second central dense portion 73c, forming an annular (tubular) shape surrounding the second central dense portion 73c. ​​When viewed in the Z direction, it is also preferable that a portion of the first central dense portion 93c overlaps with a portion of the second central dense portion 73c. ​​Even more preferably, the second central dense portion 73c is annular and is configured to cover the first central dense portion 93c when viewed in the Z direction. This further lengthens the current flow path, i.e., the conductive busbar, and more effectively suppresses the occurrence of arc discharge. For example, the central porous portion provided inside the annular second central dense portion 73c overlaps with the first central dense portion 93c in the Z direction.

[0111] Similar to the first dense portion 93 and the first central dense portion 93c, it is also preferable that at least one of the second dense portion 73 and the second central dense portion 73c has a lower capacitance than the capacitance of the second porous portion 71.

[0112] For details concerning the first central compact section 93c and the second central compact section 73c other than those mentioned above, reference is made to Japanese Patent Application Publication Nos. 2020-072261 and 2020-150257 as part of this specification.

[0113] Figure 5 This is a schematic diagram illustrating an electrostatic chuck according to other embodiments.

[0114] In this example, a countersunk portion 53s is provided in the second hole portion 53b, and a porous portion 70 is disposed in the countersunk portion 53s. The first hole portion 53a is composed of a plurality of fine holes 16. In this example, the length (diameter of the fine hole 16) of each fine hole 16 in the X or Y direction is... Figures 2-4 The width (t1a) of the illustrated first part 53aa is sufficiently small. Specifically, the diameter of the fine hole 16 is 0.01 mm to 0.2 mm.

[0115] Multiple holes 16 can be formed on the ceramic dielectric substrate 11c by means of laser irradiation or ultrasonic processing. One end of the multiple holes 16 may also be located in the groove 14. The other end of the multiple holes 16 is located on the second main surface 11b of the ceramic dielectric substrate 11. That is, the multiple holes 16 penetrate the ceramic dielectric substrate 11 in the Z direction.

[0116] exist Figure 5 In the example shown, the plurality of fine holes 16 constituting the first hole portion 53a are positioned closer to the inner side than the first protrusion 3a, which is arranged in a ring shape when viewed in the Z direction. Therefore, the puncture resistance can be improved. Furthermore, even if particles are generated due to plasma corrosion at the end 60e of the joint portion 60, particle intrusion into the fine holes 16 is suppressed. Therefore, the puncture suppression effect can be maintained. Even in this embodiment, the aforementioned puncture suppression portion (not shown) can be disposed in the third hole portion 53c. Additionally, a second central dense portion 73c can be provided in the porous portion 70 at a position where it overlaps with the plurality of fine holes 16 when viewed in the Z direction.

[0117] For example, image analysis is performed on images obtained by scanning electron microscopy to calculate the porosity in the ceramic dielectric substrate 11 and the porous portion 70. The density is measured according to JIS (Japanese Industrial Standard) C2141 5.4.3.

[0118] Manufacturing method

[0119] The manufacturing method of the electrostatic chuck according to the embodiments described above will be described below.

[0120] A ceramic dielectric substrate 11 with a porous portion 90 disposed in the first hole portion 53a and a base plate 50 with a porous portion 70 disposed in the second hole portion 53b are prepared. A joint portion 60 is formed by bonding the base plate 50 and the ceramic dielectric substrate 11 with an adhesive or the like, so that the first hole portion 53a and the second hole portion 53b face each other. A member with a first protrusion in a dense portion is used as either the porous portion 90 or the porous portion 70. Then, the porous portion 90 is disposed in the first hole portion 53a, or the porous portion 70 is disposed in the second hole portion 53b, with the first protrusion located on the joint portion 60 side.

[0121] When the first hole portion 53a is formed by a plurality of fine holes 16, the porous portion 70 is disposed in the second hole portion 53b such that the first protrusion is located on the side of the joint portion 60. Instead of preparing a ceramic dielectric substrate 11 with a plurality of fine holes 16 formed in the first hole portion 53a, a ceramic dielectric substrate 11 is prepared as the first hole portion 53a. As described above, the plurality of fine holes 16 can be formed by laser irradiation or ultrasonic processing. Furthermore, the joint portion 60 is formed such that the fine holes 16 communicate with the second hole portion 53b.

[0122] Processing device

[0123] Figure 6 This is a schematic diagram illustrating the processing apparatus 200 according to this embodiment.

[0124] like Figure 6 As shown, an electrostatic chuck 110, a power supply 210, a media supply unit 220, and a supply unit 230 can be provided in the processing device 200.

[0125] The power supply 210 is electrically connected to the electrode 12 provided on the electrostatic chuck 110. The power supply 210 can be, for example, a DC power supply. The power supply 210 applies a predetermined voltage to the electrode 12. In addition, a switch for switching the applied voltage and stopping the applied voltage can be provided in the power supply 210.

[0126] The media supply unit 220 is connected to the input path 51 and the output path 52. The media supply unit 220 can supply, for example, a liquid composed of a cooling medium or a heat-insulating medium.

[0127] The medium supply unit 220 may include, for example, a receiving unit 221, a control valve 222, and a discharge unit 223.

[0128] The containment section 221 can be, for example, a liquid storage tank or a factory piping system. Furthermore, a cooling device or a heating device for controlling the liquid temperature can be installed in the containment section 221. The containment section 221 may also include a pump for discharging the liquid.

[0129] Control valve 222 is connected between input line 51 and housing 221. Control valve 222 can control at least one of the liquid flow rate and pressure. In addition, control valve 222 can switch the liquid supply and stop the supply.

[0130] The discharge section 223 is connected to the output passage 52. The discharge section 223 can be a storage tank or drainage pipe for recovering liquid discharged from the output passage 52. Furthermore, the discharge section 223 is not always necessary; liquid discharged from the output passage 52 can also be supplied to the receiving section 221. This allows for the circulation of the cooling or insulating medium, thus achieving resource conservation.

[0131] The supply unit 230 includes a gas supply unit 231 and a gas control unit 232.

[0132] The gas supply unit 231 can be a high-pressure cylinder or plant piping that contains gases such as helium. Furthermore, although a case with one gas supply unit 231 is illustrated, multiple gas supply units 231 can also be provided.

[0133] The gas control unit 232 is connected between the multiple gas inlet paths 53 and the gas supply unit 231. The gas control unit 232 can control at least one of the gas flow rate and pressure. Furthermore, the gas control unit 232 can also have the function of switching the gas supply and stopping the supply. The gas control unit 232 can be, for example, a mass flow controller or a mass flow meter.

[0134] like Figure 6 As shown, multiple gas control units 232 can be provided. For example, the gas control units 232 can be provided in each of the multiple regions of the first main surface 11a. In this way, gas supply control can be performed in each of the multiple regions. At this time, the gas control unit 232 can also be provided in each of the multiple gas inlet paths 53. In this way, gas control in multiple regions can be performed more precisely. Furthermore, although the case of providing multiple gas control units 232 is illustrated, if the gas control unit 232 can independently control the gas supply in multiple supply systems, then only one unit is needed.

[0135] Here, methods for holding the object W include vacuum chucks and mechanical chucks. However, vacuum chucks cannot be used in environments where the pressure is reduced to a level lower than atmospheric pressure. Furthermore, if a mechanical chuck is used, the object W may be damaged or particles may be generated. Therefore, electrostatic chucks are used, for example, in processing apparatuses used in semiconductor manufacturing processes.

[0136] In such a processing apparatus, the processing space needs to be isolated from the external environment. Therefore, the processing apparatus 200 may also include a chamber 240. The chamber 240 can have an airtight structure, for example, capable of maintaining an atmosphere that is depressurized to a level lower than atmospheric pressure.

[0137] Furthermore, the processing device 200 may include multiple lifting pins and a drive device for raising and lowering the multiple lifting pins. When receiving an object W from or transferring an object W to a transport device, the lifting pins are raised by the drive device and protrude from the first main surface 11a. When placing the object W received from the transport device onto the first main surface 11a, the lifting pins are lowered by the drive device and housed inside the ceramic dielectric substrate 11.

[0138] Furthermore, various devices can be installed in the processing apparatus 200 according to the processing content. For example, a vacuum pump for venting the interior of the chamber 240 can be installed. A plasma generating device for generating plasma can be installed inside the chamber 240. A process gas supply unit for supplying process gas to the interior of the chamber 240 can be installed. A heater for heating the target object W or the process gas can also be installed inside the chamber 240. Moreover, the devices installed in the processing apparatus 200 are not limited to those illustrated. Since known technologies can be applied to the devices installed in the processing apparatus 200, detailed descriptions are omitted.

[0139] Figure 7 This is a schematic cross-sectional view of the electrostatic chuck involved in the illustrative embodiment.

[0140] Figure 8 This is a schematic diagram illustrating the processing apparatus involved in the embodiment.

[0141] Figure 7 Corresponding to Figure 1 The electrostatic chuck shown. Figure 8 Corresponding to Figure 6 The processing device shown.

[0142] like Figure 8 As shown, in this example, an electrostatic chuck 110a (an example of an electrostatic chuck 110) and a ceramic dielectric substrate 11c (an example of a ceramic dielectric substrate 11) are provided.

[0143] Figure 9 This is a schematic cross-sectional view of the electrostatic chuck involved in the illustrative embodiment.

[0144] Figure 9 This is a schematic cross-sectional view illustrating the periphery of the porous portion 90 and the porous portion 70, corresponding to... Figure 2 (a). Furthermore, in the description of the embodiments, the direction from the base plate 50 toward the ceramic dielectric substrate 11 is sometimes referred to as "upper", and the direction from the ceramic dielectric substrate 11 toward the base plate 50 is sometimes referred to as "lower". In addition, the ceramic porous portion 90 is sometimes referred to as porous portion 90, and the ceramic porous portion 70 is sometimes referred to as porous portion 70.

[0145] In the second direction (one direction within the XY plane), the first hole portion 53a is aligned with the ceramic dielectric substrate 11. The XY plane is a plane perpendicular to the Z direction. For example, the first hole portion 53a is formed by at least a portion of a hole provided in the ceramic dielectric substrate 11. In the second direction, the second hole portion 53b is aligned with the base plate 50. For example, the second hole portion 53b is formed by at least a portion of a hole provided in the base plate 50. The third hole portion 53c passes through the joint portion 60 and is aligned with the joint portion 60 in the second direction. For example, the third hole portion 53c is formed by at least a portion of a space (hole) surrounded by the joint portion 60.

[0146] For example, the outer peripheries of the first hole 53a, the second hole 53b, and the third hole 53c are circular in the XY plane. Furthermore, the term "circular" not only refers to a perfect circle (true circle), but can also include shapes where a true circle is twisted, such as ellipses or flattened circles. A cylinder is a column with a circular cross-sectional shape.

[0147] The first hole portion 53a includes a first part 53aa, a second part 53ab, and a third part 53ac. The third part 53ac is located between the first part 53aa and the second part 53ab. The third part 53ac is, for example, the space between the second surface 90b of the porous portion 90 and the ceramic dielectric substrate 11.

[0148] Part 2 53ab includes a countersunk portion 53s. For example, the outer periphery of each of Part 1 53aa, Part 2 53ab, Part 3 53ac, and the countersunk portion 53s is circular in the XY plane. The length ts (length tsa) of the countersunk portion 53s provided in Part 1 53a along the second direction is greater than the length t1a of Part 1 53aa along the second direction (see reference). Figure 2 (b) Furthermore, the length ts is, for example, the diameter of the countersunk portion 53s, and the maximum width of the planar shape of the countersunk portion 53s. The maximum width of the planar shape is the maximum value in the length along the direction in the XY plane. The length t1a is, for example, the diameter of the first part 53aa, and the maximum width of the planar shape of the first part 53aa. For example, the countersunk portion 53s provided in the first hole portion 53a is at least a portion of the portion in the first hole portion 53aa whose diameter is enlarged from that of the first part 53aa. For example, in the XY plane, the center position of the countersunk portion 53s is approximately the same as the center position of the first part 53aa.

[0149] For example, the length ts of the countersunk portion 53s along the second direction is the length tc of the third portion 53c along the second direction (refer to...). Figure 2 (b) and below. Furthermore, the length tc is, for example, the diameter of the third hole 53c, and the maximum width of the planar shape of the third hole 53c.

[0150] For example, the length t1 of the porous portion 90 along the second direction (refer to...) Figure 2 (b) is the length ts (length tsa) or less of the countersunk portion 53s. Furthermore, the length t1 is, for example, the diameter of the porous portion 90 and the maximum width of the planar shape of the porous portion 90.

[0151] The upper end of part 53aa is disposed on the first main surface 11a of the ceramic dielectric substrate 11, and is continuous with the groove 14 of the first main surface 11a. Part 53aa is directly connected to the groove 14 of the first main surface 11a. The lower end of part 53ab is disposed on the second main surface 11b of the ceramic dielectric substrate 11. The lower end of the countersunk hole portion 53s is disposed on the second main surface 11b of the ceramic dielectric substrate 11.

[0152] The ceramic dielectric substrate 11 has a countersunk surface 53ah that intersects with the inner peripheral side surface 53as of the first hole portion 53a. The countersunk surface 53ah extends, for example, in a second direction and faces downward. The lower end of the first portion 53aa is provided on the countersunk surface 53ah.

[0153] The first surface 90a of the porous portion 90 is the lower surface of the base plate 50, and the second surface 90b is the upper surface. The first surface 90a faces and contacts the third hole 53c. The first surface 90a and the second surface 90b extend, for example, along the XY plane and are essentially planar. A space is formed between the first surface 90a and the porous portion 70 (or the base plate 50).

[0154] In the second direction, the first protrusion 3a is aligned with the joint 60. This prevents the joint 60 from being exposed to plasma or gas, thus protecting it. Figure 9 In this example, the joint 60 is isolated from the space between the first surface 90a and the porous part 70 (or the base plate 50) by a first protrusion 3a provided in the porous part 90. For example, the first protrusion 3a is arranged in the space through which gas can pass in the gas inlet path 53 so that the joint 60 does not directly contact, for example.

[0155] For example, in Figure 9 In this example, the lower end of the first protrusion 3a has an annular shape in the XY plane, and contacts at least one of the porous portion 70 and the base plate 50 over the entire span of the annular shape. For example, the lower end of the first protrusion 3a contacts the second dense portion 73 of the porous portion 70. The lower end of the first protrusion 3a may also contact the second porous portion 71 of the porous portion 70.

[0156] In this example, the first protrusion 3a is separated from the end 60e of the joint 60. A space (part of the third hole 53c) is provided between the first protrusion 3a and the joint 60. However, the first protrusion 3a can also contact the end 60e.

[0157] Furthermore, the upper end of the second protrusion 3b may also contact the countersunk surface 53ah. For example, the upper end of the second protrusion 3b has an annular shape in the XY plane, and contacts the countersunk surface 53ah over the entire span of the annular shape. In this case, the middle portion 53ac includes a space divided by the countersunk surface 53ah, the second surface 90b of the porous portion 90, and the second protrusion 3b.

[0158] In addition, such as Figure 9 As shown, the second hole portion 53b has a third portion 53bu and a fourth portion 53bd. The third portion 53bu includes a countersunk portion 53s. That is, in this example, the countersunk portions 53s are respectively provided in the first hole portion 53a and the second hole portion 53b. The upper end of the third portion 53bu is provided on the upper surface 50u of the base plate 50. The upper end of the countersunk portion 53s of the second hole portion 53b is provided on the upper surface 50u. For example, the fourth portion 53bd is connected to the lower end of the countersunk portion 53s of the second hole portion 53b. The lower end of the fourth portion 53bd is provided on the lower surface 50d of the base plate 50.

[0159] For example, the outer periphery of each of the third part 53bu, the fourth part 53bd, and the countersunk portion 53s is circular in the XY plane. Figure 9 As shown, the length ts (length tsb) of the countersunk portion 53s of the second hole 53b along the second direction is greater than the length t4a of the fourth portion 53bd along the second direction. The length t4a is, for example, the diameter of the fourth portion 53bd, and the maximum width of the planar shape of the fourth portion 53bd. For example, the countersunk portion 53s of the second hole 53b is at least a portion of the second hole 53b whose diameter is enlarged from that of the fourth portion 53bd. For example, in the XY plane, the center position of the countersunk portion 53s is approximately the same as the center position of the fourth portion 53bd.

[0160] For example, the length t2 of the porous portion 70 along the second direction (refer to...) Figure 2 (b) The length tsb of the countersunk portion 53s of the second hole portion 53b is less than or equal to the length tsb of the second hole portion 53b. Furthermore, the length t2 is, for example, the diameter of the porous portion 70, and the maximum width of the planar shape of the porous portion 70. Additionally, the length t2 of the porous portion 70 in the second direction is approximately the same as the length t2b of the third portion 53bu in the second direction (see reference). Figure 2 (b)). Furthermore, the length t2b is, for example, the diameter of the third part 53bu, and the maximum width of the planar shape of the third part 53bu.

[0161] For example, length tsb is greater than length tsa, and length t2 is greater than length t1. However, this is not the only possibility; length tsb can also be the same as or less than length tsa. Similarly, length t2 can also be the same as or less than length t1.

[0162] The third surface 70a of the porous portion 70 is the upper surface of the ceramic dielectric substrate 11, and the fourth surface 70b is the lower surface. The third surface 70a faces and contacts the third hole 53c. The third surface 70a is opposite to the first surface 90a by a portion of the third hole 53c. The third surface 70a and the fourth surface 70b extend, for example, along the XY plane and are essentially planar. A space is formed between the third surface 70a and the porous portion 90 (or the ceramic dielectric substrate 11).

[0163] For example, in Figure 3 or Figure 5 In this example, the joint 60 is isolated from the space between the third surface 70a and the porous portion 90 (or the ceramic dielectric substrate 11) by the first protrusion 3a provided in the porous portion 70. This prevents the joint 60 from being exposed to plasma or gas, thus protecting it.

[0164] For example, in Figure 3 and Figure 5 In the example, the upper end of the first protrusion 3a has an annular shape in the XY plane, and contacts at least one of the porous portion 90 and the ceramic dielectric substrate 11 over the entire span of the annular shape. For example, in Figure 3 In this example, the upper end of the first protrusion 3a contacts the first dense portion 93 of the porous portion 90 and the ceramic dielectric substrate 11. The upper end of the first protrusion 3a may also contact the first porous portion 91 of the porous portion 90.

[0165] In addition, Figure 3 In the example, the first protrusion 3a contacts the end 60e of the joint 60. However, the first protrusion 3a of the porous portion 70 may also be separated from the end 60e of the joint 60. That is, a space (part of the third hole 53c) may also be provided between the first protrusion 3a of the porous portion 70 and the joint 60.

[0166] Furthermore, "substantially the same" or "identical" is not limited to being strictly the same, but can also include differences, for example, due to the degree of manufacturing deviation or the range of manufacturing clearances (e.g., slight gaps for arranging porous materials in the counterbored section).

[0167] The implementation method may also include the following configuration.

[0168] Composition 1

[0169] An electrostatic chuck, comprising:

[0170] A ceramic dielectric substrate has a first main surface on which an adsorbed object is placed and a second main surface opposite to the first main surface;

[0171] A base plate that supports the ceramic dielectric substrate has an upper surface on the side of the ceramic dielectric substrate and a lower surface on the opposite side of the upper surface;

[0172] A joint is disposed between the ceramic dielectric substrate and the base plate;

[0173] A gas inlet path passes through the ceramic dielectric substrate, the base plate, and the joint, and has a first hole in the ceramic dielectric substrate, a second hole in the base plate, and a third hole in the joint.

[0174] A countersunk hole portion is provided in at least one of the first hole portion and the second hole portion;

[0175] And a porous ceramic portion, having an exposed surface that extends into the third pore portion and being disposed in the countersink portion,

[0176] When the direction from the base plate toward the ceramic dielectric substrate is taken as the first direction, and a direction substantially orthogonal to the first direction is taken as the second direction,

[0177] The ceramic porous part has: a porous part that is breathable;

[0178] And a denser portion that is more compact than the porous portion,

[0179] The dense portion is configured to cover the outer periphery of the porous portion.

[0180] At least a portion of the dense portion constitutes a first protrusion that protrudes from the exposed surface along the first direction toward the third hole.

[0181] Composition 2

[0182] In the electrostatic chuck described in configuration 1, the length of the first protrusion from the exposed surface along the first direction is approximately the same as the length of the joint along the first direction.

[0183] Composition 3

[0184] The electrostatic chuck as described in 1 or 2 is provided in the first hole portion.

[0185] Composition 4

[0186] The electrostatic chuck described in section 3 constitutes the structure of the electrostatic chuck.

[0187] The first hole has: a first portion that opens toward the first main surface side;

[0188] Part 2, an opening is formed towards the second main surface side;

[0189] and the middle part, disposed between the first part and the second part,

[0190] The countersunk hole is located in the second part.

[0191] The length of the middle portion along the second direction is greater than the length of the first portion along the second direction.

[0192] The porous ceramic portion has a surface opposite to the exposed surface, the surface being configured to expose toward the central portion.

[0193] Composition 5

[0194] The electrostatic chuck described in configuration 4 further comprises a second protrusion protruding from the surface along the first direction toward the first portion.

[0195] Composition 6

[0196] An electrostatic chuck, comprising:

[0197] A ceramic dielectric substrate has a first main surface on which an adsorbed object is placed and a second main surface opposite to the first main surface;

[0198] A base plate that supports the ceramic dielectric substrate has an upper surface on the side of the ceramic dielectric substrate and a lower surface on the opposite side of the upper surface;

[0199] A joint is disposed between the ceramic dielectric substrate and the base plate;

[0200] A gas inlet path passes through the ceramic dielectric substrate, the base plate, and the joint, and has a first hole in the ceramic dielectric substrate, a second hole in the base plate, and a third hole in the joint.

[0201] A countersunk hole is provided in the second hole portion;

[0202] And a porous ceramic portion, having an exposed surface that extends into the third pore portion and being disposed in the countersink portion,

[0203] When the direction from the base plate toward the ceramic dielectric substrate is taken as the first direction, and a direction substantially orthogonal to the first direction is taken as the second direction,

[0204] The ceramic porous part has: a porous part that is breathable;

[0205] And a denser portion that is more compact than the porous portion,

[0206] The dense portion is configured to cover the outer periphery of the porous portion.

[0207] At least a portion of the dense portion constitutes a first protrusion that projects from the exposed surface along the first direction toward the third hole.

[0208] The first aperture contains multiple fine holes.

[0209] Composition 7

[0210] A processing device, characterized in that,

[0211] It possesses: an electrostatic chuck as described in any of items 1 to 6;

[0212] And a supply unit capable of supplying gas to the gas inlet path provided in the electrostatic chuck.

[0213] In this application specification, "perpendicular," "parallel," and "orthogonal" are not limited to strict perpendicularity, strict parallelism, and strict orthogonality, but also include, for example, deviations in the manufacturing process, as long as they are substantially perpendicular, substantially parallel, and substantially orthogonal.

[0214] The embodiments of the present invention have been described above. However, the present invention is not limited to the above description. For example, although a structure utilizing Coulomb force is illustrated as the electrostatic chuck 110, a structure utilizing Johnson-Rabec force can also be applied. Furthermore, regarding the foregoing embodiments, techniques that can be appropriately modified by those skilled in the art to incorporate the features of the present invention are also included within the scope of the present invention. In addition, as long as it is technically feasible, the elements of the foregoing embodiments can be combined, and such combined techniques, as long as they incorporate the features of the present invention, are also included within the scope of the present invention.

Claims

1. An electrostatic chuck, comprising: A ceramic dielectric substrate has a first main surface on which an adsorbed object is placed and a second main surface opposite to the first main surface; A base plate that supports the ceramic dielectric substrate has an upper surface on the side of the ceramic dielectric substrate and a lower surface on the opposite side of the upper surface; A joint is disposed between the ceramic dielectric substrate and the base plate; A gas inlet path passes through the ceramic dielectric substrate, the base plate, and the joint, and has a first hole in the ceramic dielectric substrate, a second hole in the base plate, and a third hole in the joint. A countersunk hole portion is provided in at least one of the first hole portion and the second hole portion; And a porous ceramic portion, having an exposed surface that extends into the third pore portion and being disposed in the countersunk portion, characterized in that, When the direction from the base plate toward the ceramic dielectric substrate is taken as the first direction, and a direction substantially orthogonal to the first direction is taken as the second direction, The ceramic porous part has: a porous part that is breathable; And a denser portion that is more compact than the porous portion, The dense portion is configured to cover the outer periphery of the porous portion. At least a portion of the dense portion constitutes a first protrusion that protrudes from the exposed surface along the first direction toward the third hole.

2. The electrostatic chuck according to claim 1, characterized in that, The length of the first protrusion from the exposed surface along the first direction is approximately the same as the length of the joint along the first direction.

3. The electrostatic chuck according to claim 1 or 2, characterized in that, The countersunk hole is located in the first hole.

4. The electrostatic chuck according to claim 3, characterized in that, The first hole has: a first portion that opens toward the first main surface side; Part 2, an opening is formed towards the second main surface side; and the middle part, disposed between the first part and the second part, The countersunk hole is located in the second part. The length of the middle portion along the second direction is greater than the length of the first portion along the second direction. The porous ceramic portion has a surface opposite to the exposed surface, the surface being configured to expose toward the central portion.

5. The electrostatic chuck according to claim 4, characterized in that, The dense portion also has a second protrusion that protrudes from the surface along the first direction toward the first portion.

6. An electrostatic chuck, comprising: A ceramic dielectric substrate has a first main surface on which an adsorbed object is placed and a second main surface opposite to the first main surface; A base plate that supports the ceramic dielectric substrate has an upper surface on the side of the ceramic dielectric substrate and a lower surface on the opposite side of the upper surface; A joint is disposed between the ceramic dielectric substrate and the base plate; A gas inlet path passes through the ceramic dielectric substrate, the base plate, and the joint, and has a first hole in the ceramic dielectric substrate, a second hole in the base plate, and a third hole in the joint. A countersunk hole is provided in the second hole portion; And a porous ceramic portion, having an exposed surface that extends into the third pore portion and being disposed in the countersunk portion, characterized in that, When the direction from the base plate toward the ceramic dielectric substrate is taken as the first direction, and a direction substantially orthogonal to the first direction is taken as the second direction, The ceramic porous part has: a porous part that is breathable; And a denser portion that is more compact than the porous portion, The dense portion is configured to cover the outer periphery of the porous portion. At least a portion of the dense portion constitutes a first protrusion that projects from the exposed surface along the first direction toward the third hole. The first aperture contains multiple fine holes.

7. A processing apparatus, characterized in that, It possesses: the electrostatic chuck described in any one of claims 1, 2 and 6; And a supply unit capable of supplying gas to the gas inlet path provided in the electrostatic chuck.

Images