Electrostatic chuck

Abstract

Provided is an electrostatic chuck capable of suppressing deviation in in-plane temperature distribution of a substrate. The electrostatic chuck includes: a dielectric substrate having a placement surface, i.e., a surface; an RF electrode provided inside the dielectric substrate; a base plate formed of metal and joined to the dielectric substrate; and a conductive member electrically connecting between the RF electrode and the base plate. A portion of the conductive member is housed in a first recess formed on the surface on the base plate side of the dielectric substrate. An end portion of the conductive member on the base plate side abuts against the surface on the dielectric substrate side of the base plate or against a bottom surface of a recess formed on the surface, i.e., a second recess shallower than the first recess.

Description

Technical Field

[0001] This invention relates to an electrostatic chuck. Background Technology

[0002] For example, in semiconductor manufacturing apparatuses such as etching equipment, electrostatic chucks are provided as devices for adsorbing and holding substrates such as silicon wafers that are to be processed. An electrostatic chuck comprises: a dielectric substrate on which adsorption electrodes are provided; and a base plate supporting the dielectric substrate, having a structure in which these are joined together. When a voltage is applied to the adsorption electrodes, an electrostatic force is generated, adsorbing and holding the substrate placed on the dielectric substrate.

[0003] As described in Patent Document 1 below, an RF electrode is sometimes built into the dielectric substrate. The RF electrode is an internal electrode disposed within the dielectric substrate as one of a pair of opposing electrodes used to generate plasma in a semiconductor manufacturing apparatus. The RF electrode is electrically connected to the base plate by a conductive member. Thus, during substrate processing, the potential of the RF electrode is maintained at the potential of the base plate.

[0004] Patent documents Patent Document 1: International Publication No. 2022 / 255118 Summary of the Invention

[0005] To electrically connect the conductive member to the RF electrode, a recess can be formed on the substrate side of the dielectric substrate, exposing the RF electrode on its bottom surface. The conductive member can then be housed inside the recess. Similarly, to electrically connect the conductive member to the substrate, a recess can be formed on the substrate side of the substrate, and the conductive member can be housed inside the recess. In this case, a portion of the conductive member is housed in the recess of the dielectric substrate, and another portion is housed in the recess of the substrate.

[0006] However, the base plate needs to have the function of cooling the substrate during the dielectric substrate process and maintaining a uniform in-plane temperature distribution of the substrate. It is assumed that when the aforementioned recess formed on the base plate is formed too deep, the cooling function of the base plate in that portion may decrease, and the temperature of the substrate directly above it may locally rise. In other words, the portion of the substrate directly above the recess may become a so-called "hot spot."

[0007] The present invention was made in view of the following problem, and its object is to provide an electrostatic chuck that can suppress deviations in the in-plane temperature distribution of a substrate.

[0008] To address the aforementioned problems, the electrostatic chuck of the present invention comprises: a dielectric substrate having a mounting surface for placing an object to be attracted; an internal electrode disposed inside the dielectric substrate; a base plate formed of metal and bonded to the dielectric substrate; and a conductive member for electrically connecting the internal electrode and the base plate. A portion of the conductive member is housed in a first recess formed on a surface of the dielectric substrate on the base plate side. The end of the conductive member on the base plate side either abuts against the surface of the base plate on the dielectric substrate side or abuts against the bottom surface of a second recess formed on that surface, which is shallower than the first recess.

[0009] In this electrostatic chuck configuration, a second recess, which could potentially become a hotspot, is either shallowly formed at the location on the base plate corresponding to the conductive member, or the second recess itself is not formed. This suppresses localized temperature rise directly above the conductive member, thereby suppressing deviations in the in-plane temperature distribution of the substrate during processing.

[0010] According to the present invention, an electrostatic chuck capable of suppressing deviations in the in-plane temperature distribution of a substrate can be provided. Attached Figure Description

[0011] Figure 1 This is a cross-sectional view showing the structure of the electrostatic chuck according to the first embodiment. Figure 2 This is a cross-sectional view showing in detail the structure of the conductive component and its surrounding portion of the electrostatic chuck according to the first embodiment. Figure 3 It is a three-dimensional diagram showing the structure of a conductive component. Figure 4 This is a diagram illustrating the manufacturing method of the electrostatic chuck according to the first embodiment. Figure 5 This is a cross-sectional view showing in detail the structure of the conductive component and its surrounding portion of the electrostatic chuck according to the second embodiment. Figure 6 This is a cross-sectional view showing in detail the structure of the conductive component and its surrounding portion of the electrostatic chuck according to the third embodiment. Symbol Explanation 10-Electrostatic chuck; 100-Dielectric substrate; 110, 120-Surface; 160-First recess; 140-RF electrode; 200-Base plate; 210-Surface; 260-Second recess; 262-Bottom surface; 400-Conductive component; W-Substrate. Detailed Implementation

[0012] Hereinafter, this embodiment will be described with reference to the accompanying drawings. For ease of understanding, the same symbols will be used to label the same components as much as possible in each drawing, and repeated descriptions will be omitted.

[0013] The first embodiment will be described. The electrostatic chuck 10 of this embodiment, for example, is used inside a semiconductor manufacturing apparatus (not shown) such as an etching apparatus to attract and hold a substrate W to be processed by electrostatic force. The attracted object, i.e., the substrate W, is, for example, a silicon wafer. The electrostatic chuck 10 can also be used in apparatuses other than semiconductor manufacturing apparatuses.

[0014] Figure 1 The diagram shows the structure of an electrostatic chuck 10 in a state of adsorbing and holding a substrate W, as a schematic cross-sectional view. The electrostatic chuck 10 includes a dielectric substrate 100 and a base plate 200.

[0015] The dielectric substrate 100 is a generally disk-shaped component made of sintered ceramic body. Although the dielectric substrate 100 may contain, for example, high-purity alumina (Al2O3), other materials may also be included. Considering the plasma resistance and other requirements of the dielectric substrate 100 in semiconductor manufacturing equipment, the purity and type of ceramic, additives, etc. in the dielectric substrate 100 can be appropriately set.

[0016] In dielectric substrate 100, Figure 1 The upper side surface 110 of the dielectric substrate 100 becomes the "mounting surface" of the substrate W. Additionally, in the dielectric substrate 100, Figure 1 The lower side surface 120 becomes the "joined surface" that is joined to the base plate 200 by the joining layer 300. Hereinafter, the viewpoint when viewing the electrostatic chuck 10 from the side of surface 110 along the direction perpendicular to surface 110 will also be described as "top view".

[0017] An adsorption electrode 130 is embedded inside the dielectric substrate 100. The adsorption electrode 130 is a thin, flat layer formed of a metal material such as tungsten, and is arranged parallel to the surface 110. Besides tungsten, molybdenum, platinum, palladium, etc., can also be used as the material for the adsorption electrode 130. If a voltage is applied to the adsorption electrode 130 from the outside via a power supply circuit (not shown), an electrostatic force is generated between the surface 110 and the substrate W, thereby adsorbing and holding the substrate W. Various known structures can be used as the structure of the power supply circuit. The adsorption electrode 130 can be provided as a single "monopolar" electrode as in this embodiment, or as two "bipolar" electrodes.

[0018] Inside the dielectric substrate 100, in addition to the aforementioned adsorption electrode 130, an RF electrode 140 is also embedded. The RF electrode 140 is provided as one of a pair of opposing electrodes used to generate plasma in a semiconductor manufacturing apparatus. The other opposing electrode is positioned closer to the upper side than the electrostatic chuck 10 in the semiconductor manufacturing apparatus. If a high-frequency alternating voltage is applied between these opposing electrodes, plasma is generated on the upper side of the substrate W for use in processes such as film deposition or etching of the substrate W. The RF electrode 140 corresponds to the "internal electrode" in this embodiment.

[0019] Similar to the adsorption electrode 130, the RF electrode 140 is also a thin, flat layer formed of a metallic material such as tungsten. Besides tungsten, other materials for the RF electrode 140 include molybdenum, platinum, and palladium. The RF electrode 140 is positioned closer to surface 120 than the adsorption electrode 130. Like the adsorption electrode 130, the RF electrode 140 is also configured parallel to surface 110. When viewed from above, the RF electrode 140 is a generally circular single electrode. When viewed from above, the center of the RF electrode 140 coincides with the center of the dielectric substrate 100.

[0020] The electrostatic chuck 10 is provided with a conductive member 400. The conductive member 400 is a member used to electrically connect the RF electrode 140 and the base plate 200 (described later). Through the conductive member 400, during the processing of the substrate W, the potential of the RF electrode 140 is the same as the potential of the base plate 200. Figure 1 In the diagram, the conductive component 400 is drawn as a simple straight line. The specific shape of the conductive component 400 will be explained later.

[0021] like Figure 1 As shown, a space SP is formed between the dielectric substrate 100 and the substrate W. During etching or other processes in a semiconductor manufacturing apparatus, temperature-regulating helium gas is supplied to the space SP from the outside through a vent (not shown). By having helium gas present between the dielectric substrate 100 and the substrate W, the thermal resistance between them is adjusted, thereby maintaining the temperature of the substrate W at an appropriate temperature. Furthermore, the gas supplied to the space SP for temperature regulation can also be a gas of a different type than helium.

[0022] A sealing ring 111 and a point 112 are provided on the mounting surface, i.e., surface 110, and the aforementioned space SP is formed around these.

[0023] The sealing ring 111 is a wall that divides the space SP at the outermost circumference position. The sealing ring 111 is an annular protrusion formed on the side of the surface 110. The top of the sealing ring 111 ( Figure 1The upper end of the sealing ring 111 becomes part of the surface 110 and abuts against the substrate W. It can be said that the top end of the sealing ring 111 is the part located on the outermost periphery of the mounting surface, i.e., the surface 110.

[0024] Furthermore, multiple sealing rings 111 can be provided in a segmented space SP manner. By adopting such a structure, the pressure of helium gas in each space SP can be adjusted individually, which can make the surface temperature distribution of the substrate W during processing more uniform.

[0025] Figure 1 In the diagram, the portion marked with the symbol "116" is the bottom surface of space SP. Hereinafter, this portion will also be referred to as "bottom surface 116". The sealing ring 111, together with point 112 described below, is formed as a result of excavating a portion of surface 110 up to the position of bottom surface 116.

[0026] Point 112 is a circular protrusion extending from the bottom surface 116. Multiple points 112 are provided and are distributed approximately evenly on the mounting surface of the dielectric substrate 100. The tip of each point 112 becomes part of the surface 110 and abuts against the substrate W. By providing multiple such points 112, bending of the substrate W is suppressed.

[0027] The base plate 200 is a generally disk-shaped component that supports the dielectric substrate 100. The base plate 200 is formed of a metal material, such as aluminum. The base plate 200 is bonded to surface 120 of the dielectric substrate 100 by a bonding layer 300. The base plate 200... Figure 1 The upper side surface 210 becomes the "bonded surface" that is bonded to the dielectric substrate 100.

[0028] The bonding layer 300 is a layer disposed between the dielectric substrate 100 and the base plate 200, bonding the two together. The bonding layer 300 is a layer formed by curing an adhesive material made of an insulating material. In this embodiment, a silicone adhesive is used as the adhesive. However, the bonding layer 300 can also be a layer formed by curing other types of adhesives. In any case, it is preferable to use a material with the highest possible thermal conductivity as the material for the bonding layer 300, so as to minimize the thermal resistance between the dielectric substrate 100 and the base plate 200.

[0029] An insulating film may also be formed on the surface of the base plate 200. For example, an alumina film formed by thermal spraying can be used as the insulating film. By covering the surface of the base plate 200 with the insulating film, the insulation withstand voltage of the base plate 200 can be improved. The insulating film can be formed to cover the entire surface of the base plate 200, or it can be formed to cover only a portion of the surface of the base plate 200, for example, only surface 210.

[0030] Inside the base plate 200, a cooling medium flow path 250 is formed for the passage of a cooling medium. During processes such as etching in a semiconductor manufacturing apparatus, a cooling medium is supplied from the outside to the cooling medium flow path 250, thereby cooling the base plate 200. During processing, heat generated on the substrate W is transferred to the cooling medium via helium gas in the space SP, the dielectric substrate 100, and the base plate 200, and is discharged to the outside along with the cooling medium. In the base plate 200, the cooling medium for the cooling medium flow path 250 is supplied and discharged through an opening (not shown) formed on the surface 220 opposite to surface 210.

[0031] Reference Figure 2 The specific structure of the conductive member 400 and its surrounding area will be described. As shown in the figure, a first recess 160 is formed on the surface 120 of the dielectric substrate 100 on the side of the base plate 200. The first recess 160 is a portion of the surface 120 that recedes concavely toward the surface 110 so that the conductive member 400 can be disposed. In this embodiment, the first recess 160 is formed to a depth that exposes the RF electrode 140. Therefore, the internal electrode, i.e., the RF electrode 140, is exposed on the bottom surface 162 of the first recess 160. When viewed from above, the first recess 160 is circular in shape, and a generally cylindrical space is formed inside it.

[0032] A second recess 260 is formed on the surface 210 of the base plate 200 on the dielectric substrate 100 side. The second recess 260 is formed on the surface 210 and overlaps with the first recess 160 when viewed from above. The second recess 260 is a portion of the surface 210 that is recessed towards the surface 220 to allow for the placement of the conductive member 400. The metal portion of the base plate 200 is entirely exposed inside the second recess 260. When viewed from above, the second recess 260 is circular in shape, with a generally cylindrical space formed inside. The central axis of the second recess 260 coincides with the central axis of the first recess 160. However, the diameter D2 of the inner peripheral surface 261 of the second recess 260 is larger than the diameter D1 of the inner peripheral surface 161 of the first recess 160.

[0033] On the bonding layer 300, a circular opening is formed in the portion between the first recess 160 and the second recess 260. The first recess 160 and the second recess 260 are connected by this opening, and these together form a space.

[0034] Figure 2The component marked with the symbol "310" is configured to prevent uncured adhesive from entering the inner side of the first recess 160 and the second recess 260. Hereinafter, this component will also be referred to as "blocking portion 310". The blocking portion 310 is a ring-shaped component configured to surround the second recess 260 from the outside across its entire circumference when viewed from above. Although the inner diameter of the blocking portion 310 is the same as the inner diameter of the second recess 260 (the aforementioned diameter D2), it can also be a different size. For example, cured silicone adhesive can be used as the blocking portion 310.

[0035] The conductive member 400 is a generally cylindrical member formed of fibrous metal components and is housed inside the first recess 160 and the second recess 260. That is, a portion of the conductive member 400 is housed in the first recess 160, and another portion is housed in the second recess 260. When viewed from above, the diameter of the portion of the conductive member 400 housed in the first recess 160 is equal to the diameter of the portion housed in the second recess 260.

[0036] The end of the conductive component 400 on the dielectric substrate 100 side ( Figure 2 The upper end of the conductive member 400 abuts against the RF electrode 140 exposed on the bottom surface 162 of the first recess 160. Additionally, the end of the conductive member 400 on the base plate 200 side ( Figure 2 The lower end of the second recess 260 abuts against the bottom surface 262 of the second recess 260. The conductive member 400 configured in this way electrically connects the RF electrode 140 to the metal portion of the base plate 200.

[0037] like Figure 3 As shown, the conductive member 400 has a generally cylindrical body portion 410 and a plurality of protrusions 420, and is integrally formed from a fibrous metal member. Each protrusion 420 is a generally cylindrical projection extending further from the surface of the body portion 410 toward the dielectric substrate 100 side. In this embodiment, a total of four protrusions 420 are formed, but the number of protrusions 420 may also differ.

[0038] The conductive component 400, composed of fibrous metal parts, has a degree of permeability that allows fluids such as air or adhesives to enter its interior. In other words, the fibrous metal parts are not completely dense; rather, gaps exist between the fibers. By employing this structure, the conductive component 400 becomes an elastic body, including the protrusions 420, whose parts are easily deformable under external forces.

[0039] When not subjected to external force, the vertical dimension of the conductive member 400 (the extension direction of the protrusion 420) is greater than that of the other member. Figure 2The dimensions in the same direction under the same state. That is, the conductive member 400 is housed inside the first recess 160 and the second recess 260 in a compressed state along the direction from the dielectric substrate 100 toward the base plate 200, and sandwiched between the RF electrode 140 and the base plate 200. The top tip of each protrusion 420 is pressed against the bottom surface 162 of the first recess 160 (that is, the RF electrode 140), and thus undergoes elastic deformation in a flattened manner.

[0040] The conductive component 400 is pressed against both the RF electrode 140 and the base plate 200 by its own restoring force. Therefore, even if the parts of the electrostatic chuck 10 undergo thermal expansion or contraction during the processing of the substrate W, the RF electrode 140 and the base plate 200 remain electrically connected.

[0041] The number of conductive members 400 can be one or more. For example, multiple members can be arranged in a circumferential manner to form a space composed of the first recess 160 and the second recess 260, so that each space contains one conductive member 400.

[0042] The conductive member 400 may also have a shape different from that in this embodiment. For example, the conductive member 400 may be made into a generally cylindrical shape and may not have a protrusion 420.

[0043] return Figure 2 Continuing with the explanation, "L1" shown in the figure represents the depth of the first recess 160. In this embodiment, this depth is equal to the distance from surface 120 to bottom surface 162. Alternatively, L1 can be described as... Figure 2 The dimension of the portion of the conductive member 400 housed in the first recess 160 in the state of being perpendicular to the mounting surface.

[0044] Figure 2 The "L2" shown indicates the depth of the second recess 260. In this embodiment, this depth is equal to the distance from surface 220 to bottom surface 262. Alternatively, L2 can be described as... Figure 2 The dimension of the portion of the conductive member 400 housed in the second recess 260 in the state of being perpendicular to the mounting surface.

[0045] In this embodiment, the depth (L2) of the second recess 260 is less than the depth (L1) of the first recess 160. That is, the second recess 260 is formed as a shallower recess than the first recess 160.

[0046] However, the base plate 200 needs to have the function of cooling the substrate W during the dielectric substrate 100 process and maintaining a uniform in-plane temperature distribution of the substrate W. It is assumed that when the second recess 260 formed on the base plate 200 is formed deeper, the cooling function of the base plate 200 in that portion may decrease, and the temperature of the substrate W directly above it may locally rise. In other words, the portion of the substrate W located directly above the second recess 260 may become a so-called "hot spot."

[0047] Therefore, in this embodiment, as described above, the second recess 260 is formed shallower so that L2 is less than L1. Since the increase in thermal resistance accompanying the formation of the second recess 260 is suppressed to be smaller than before, it is possible to suppress the local temperature rise directly above the conductive member 400 and suppress the deviation of the in-plane temperature distribution of the substrate W during processing.

[0048] Figure 2 The “L3” shown is the overall dimension of the conductive member 400 in the direction perpendicular to the mounting surface. Specifically, it is the overall dimension of the conductive member 400 in the direction perpendicular to the mounting surface when it is compressed inside the first recess 160 and the second recess 260. L3 is equal to the distance from the bottom surface 162 of the first recess 160 to the bottom surface 262 of the second recess 260.

[0049] In this embodiment, the shapes of the conductive member 400, the first recess 160, and the second recess 260 are adjusted so that the dimension of the portion of the conductive member 400 housed in the first recess 160 in the direction perpendicular to the mounting surface (i.e., L1) is more than 1 / 2 of the overall dimension of the conductive member 400 in the same direction (i.e., L3).

[0050] To illustrate the advantages of using this structure, refer to... Figure 4 The method for bonding the dielectric substrate 100 and the base plate 200 in the manufacturing method of the electrostatic chuck 10 will be described. In this figure, the structures of the dielectric substrate 100, the base plate 200 and the conductive member 400 are drawn in a simplified and schematic manner.

[0051] First, with surface 120 facing upwards, the dielectric substrate 100 is placed on a worktable (not shown). A first recess 160 is pre-formed on surface 120. In addition, an adhesive that will cure and become a bonding layer 300 is pre-coated onto the substantially entire surface 120. Figure 4 The illustration of the adhesive is omitted. The adhesive can also be pre-applied to surface 220 of the base plate 200.

[0052] Next, conductive members 400 are inserted into their respective first recesses 160. For example... Figure 4 As shown, each conductive component 400 is in a state where a portion of it protrudes vertically from the surface 120 of the dielectric substrate 100.

[0053] Then, with surface 210 facing downwards, the base plate 200 is brought closer to surface 120 from above. A second recess 260 is pre-formed on surface 210. Furthermore, the dielectric substrate 100 and the base plate 200 are aligned so that each of the second recesses 260 is directly above its respective first recess 160. While along... Figure 4 The arrow moves the base plate 200 while bonding it to the dielectric substrate 100. When the movement ends, each conductive member 400 is housed inside the first recess 160 and the second recess 260. Then, the entire assembly is heated to cure the adhesive, thereby completing the process. Figure 1 The electrostatic chuck 10 is shown.

[0054] When along Figure 4 When the arrow moves the base plate 200, if the first recess 160 formed on the surface 120 is too shallow, the conductive member 400 inserted into the first recess 160 is prone to tipping over, significantly reducing workability. Furthermore, if the diameter D1 of the inner circumferential surface 161 of the first recess 160 is too large, it is inherently difficult to position the conductive member 400 in a state of vertical protrusion from the surface 120, and there is also the possibility that the conductive member 400 cannot be correctly positioned in this state.

[0055] Therefore, in this embodiment, the diameter D1 of the inner peripheral surface 161 of the first recess 160 is made to be approximately the same size as the diameter of the body portion 410 of the conductive member 400, while the depth (L1) of the first recess 160 is made to be at least half the overall length (L3) of the conductive member 400. By adopting such a structure, when the dielectric substrate 100 and the base plate 200 are joined, it is possible to prevent the conductive member 400 from tipping over.

[0056] Suppose that when the diameter D2 of the inner peripheral surface 261 of the second recess 260 formed on the base plate 200 is smaller than the size in this embodiment, for example, approximately the same as the diameter D1 of the inner peripheral surface 161 of the first recess 160, it is difficult to align the base plate 200 with the dielectric substrate 100 on the lower side. In other words, it is difficult to allow the respective conductive members 400 to enter the inner side of the second recess 260.

[0057] Therefore, in this embodiment, the shapes of the first recess 160 and the second recess 260 were studied such that the second recess 260 is larger than the first recess 160 when viewed from above. Specifically, the diameter D2 of the inner circumferential surface 261 is made larger than the diameter D1 of the inner circumferential surface 161. As a result, the base plate 200 can be moved downwards while the respective conductive members 400 can easily enter the inside of the second recess 260.

[0058] The second embodiment will be described below. Hereinafter, the parts that differ from the first embodiment will be described in detail, and the parts that are the same as those in the first embodiment will be omitted as appropriate.

[0059] Figure 5 In, with Figure 2 The structure of the electrostatic chuck 10 according to this embodiment is drawn from the same perspective. For example... Figure 5 As shown, in this embodiment, the first recess 160 is not formed to a depth that exposes the RF electrode 140. The bottom surface 162 of the first recess 160 is located closer to the surface 120 than the RF electrode 140.

[0060] The bottom surface 162 of the first recess 160 is covered by a metal plate 141. The metal plate 141 is, for example, a plate-shaped component formed of molybdenum, which is attached to the generally whole bottom surface 162. In this embodiment, the tip of the protrusion 420 is pressed against the metal plate 141.

[0061] A plurality of vias 142 provided on the dielectric substrate 100 electrically connect the metal plate 141 and the RF electrode 140. The vias 142 are formed inside holes extending in a direction perpendicular to the surface 120, and are filled, for example, with a conductive material such as tungsten. One end of the via 142 is connected to the metal plate 141, and the other end is connected to the RF electrode 140.

[0062] Thus, in this embodiment, the conductive member 400 and the RF electrode 140 are not directly connected, but are indirectly connected via the metal plate 141 and the via portion 142. Even in this configuration, the same effects as described in the first embodiment are achieved.

[0063] In this embodiment, "L1" refers to the depth of the first recess 160, which is equal to the distance from the surface of the metal plate 141 on the base plate 200 side to the surface 120. Even in this embodiment, as in the first embodiment, L2 is less than L1, and L1 is more than half of L3.

[0064] Furthermore, in the structure of this embodiment, the circuit in the via 142 is relatively narrow, thus increasing the resistance of the via 142 and potentially generating significant Joule heating. To suppress the resulting localized temperature rise, it is preferable to maximize the depth (L1) of the first recess 160 and shorten the via 142. In other words, in the structure of this embodiment, compared to the first embodiment, it is particularly necessary to form the first recess 160, etc., with L1 > L2.

[0065] The third embodiment will be described. Hereinafter, the parts that differ from the first embodiment will be mainly described, and the parts that are the same as those in the first embodiment will be omitted as appropriate.

[0066] Figure 6 In, with Figure 2 The structure of the electrostatic chuck 10 according to this embodiment is drawn from the same perspective. In this embodiment, the second recess 260 is not formed on the surface 210 of the base plate 200. The end of the conductive member 400 on the base plate 200 side abuts against the surface 210 on the dielectric substrate 100 side of the base plate 200. It can also be said that this structure is a structure in which the depth (L2) of the second recess 260 is made 0. Even in this configuration, the same effects as those described in the first embodiment are achieved.

[0067] As described in the first embodiment, an insulating film may also be formed on the base plate 200 in such a way as a covering surface 210. In this case, at least the portion of the conductive member 400 on the surface 210 that abuts is not formed with an insulating film, but rather the metal portion of the base plate 200 is exposed.

[0068] The present embodiment has been described above with reference to specific examples. However, the present invention is not limited to these specific examples. Regarding these specific examples, any design modifications made by those skilled in the art that possess the features of the present invention are also included within the scope of the present invention. The elements, their configurations, conditions, shapes, etc., of the foregoing specific examples are not limited to the illustrated content, but can be appropriately modified. As long as there is no technical contradiction, the elements of the foregoing specific examples can be appropriately changed and combined.

Claims

1. An electrostatic chuck, characterized in that, Features: a dielectric substrate having a mounting surface for placing the adsorbed material; Internal electrodes are disposed inside the dielectric substrate; A base plate, formed of metal and bonded to the dielectric substrate; And conductive components, for electrically connecting the internal electrodes and the base plate. A portion of the conductive member is housed in a first recess formed on the surface of the dielectric substrate on the side of the base plate. The end of the conductive member on the base plate side either abuts against the surface of the base plate on the dielectric substrate side, or abuts against the bottom surface of a recess formed on that surface, namely a second recess that is shallower than the first recess.

2. The electrostatic chuck according to claim 1, characterized in that, The dimension of the portion of the conductive member housed in the first recess, in the direction perpendicular to the mounting surface, is more than 1 / 2 of the overall dimension of the conductive member in that direction.

3. The electrostatic chuck according to claim 2, characterized in that, The second recess is formed on the base plate. When viewed from a direction perpendicular to the mounting surface, the second recess is larger than the first recess.

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