electrostatic chuck

Abstract

An electrostatic chuck capable of suppressing variations in the in-plane temperature distribution of a substrate during processing. [Solution] An electrostatic chuck (10) includes a dielectric substrate (100) having a through hole (140) formed therein, a plurality of heat generating portions (431) linearly routed inside the dielectric substrate (100), and a bypass portion (450) which is an electric circuit provided inside the dielectric substrate (100) and electrically connected to the heat generating portions (431). In this electrostatic chuck (10), when viewed from above, a shortest distance (L2) from the inner surface of the through hole (140) to the bypass portion (450) is greater than a shortest distance (L1) from the inner surface of the through hole (140) to the heat generating portions (431).

Description

Technical Field

[0001] The present invention relates to an electrostatic chuck.

Background Art

[0002] For example, in semiconductor manufacturing equipment such as an etching apparatus, an electrostatic chuck is provided as a device for adsorbing and holding a substrate such as a silicon wafer to be processed. The electrostatic chuck has a dielectric substrate provided with adsorption electrodes. When a voltage is applied to the adsorption electrodes, an electrostatic force is generated, and the substrate placed on the dielectric substrate is adsorbed and held.

[0003] During the processing of the substrate, it is required to make the in-plane temperature distribution of the substrate as uniform as possible. In order to be able to adjust the in-plane temperature distribution of the substrate with high precision, in recent years, an electrostatic chuck equipped with a heater for heating the dielectric substrate has also been developed and has already been put into practical use. For example, in the electrostatic chuck described in Patent Document 1 below, both a heating part which is a conductor routed linearly and a bypass part which is an electric circuit for supplying power to the heating part are embedded inside the dielectric substrate. By individually adjusting the calorific value of each of the plurality of heating parts, it becomes possible to approximate the in-plane temperature distribution of the substrate during processing to be uniform.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The dielectric substrate often has through-holes perpendicular to the placement surface. Examples of such through-holes include gas holes for supplying an inert gas to the substrate side, lift pin holes for passing lift pins, and the like.

[0006] The area near the through-holes in the dielectric substrate is prone to becoming a temperature singularity. In other words, the area near the through-holes is more susceptible to localized temperature increases and decreases compared to other areas. Therefore, in the region of the dielectric substrate that includes the area near the through-holes, it is necessary to place the heat-generating part as close to the through-holes as possible and to precisely control the temperature in that region.

[0007] In many cases, bypass sections are placed in addition to heat-generating sections near through-holes. In such configurations, Joule heating generated in the bypass sections can act as a disturbance, potentially negatively impacting precise temperature control in the vicinity of the through-holes. As a result, variations in the in-plane temperature distribution of the substrate during processing may increase.

[0008] The present invention has been made in view of these problems, and its objective is to provide an electrostatic chuck that can suppress variations in the in-plane temperature distribution of a substrate during processing. [Means for solving the problem]

[0009] To solve the above problems, the electrostatic chuck according to the present invention comprises a dielectric substrate having a mounting surface on which an object to be adsorbed is placed and having through holes perpendicular to the mounting surface; a plurality of heating elements linearly routed inside the dielectric substrate; and a bypass section provided inside the dielectric substrate that is electrically connected to the heating elements. When viewed from a direction perpendicular to the mounting surface, the shortest distance from the inner surface of the through hole to the bypass section is greater than the shortest distance from the inner surface of the through hole to the heating element.

[0010] In this type of electrostatic chuck, the shortest distance from the inner surface of the through-hole to the bypass section is longer than in conventional designs. This makes it possible to precisely control the temperature in the vicinity of the through-hole in the dielectric substrate while reducing the effect of Joule heating generated in the bypass section. As a result, variations in the in-plane temperature distribution of the substrate during processing can be suppressed. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an electrostatic chuck that can suppress variations in the in-plane temperature distribution of a substrate during processing. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic cross-sectional view showing the configuration of the electrostatic chuck according to the first embodiment. [Figure 2] This figure shows an example of how to divide a dielectric substrate into regions for arranging different heat-generating components. [Figure 3] This figure shows an example of a heat-generating component routed within a single region. [Figure 4] This is a diagram to explain the role of the bypass section, etc. [Figure 5] This is a schematic cross-sectional view showing the configuration of the portion of the electrostatic chuck near the through hole according to the first embodiment. [Figure 6] This is a schematic cross-sectional view showing the configuration of the portion of the electrostatic chuck near the through hole according to the second embodiment. [Modes for carrying out the invention]

[0013] This embodiment will now be described with reference to the attached drawings. To facilitate understanding of the explanation, the same reference numerals are used for identical components in each drawing whenever possible, and redundant explanations are omitted.

[0014] A first embodiment will be described. The electrostatic chuck 10 according to this embodiment is used to attract and hold a substrate W to be processed by electrostatic force inside a semiconductor manufacturing apparatus (not shown), such as an etching apparatus. The substrate W to be attracted is, for example, a silicon wafer. The electrostatic chuck 10 may also be used in apparatus other than semiconductor manufacturing apparatus.

[0015] FIG. 1 shows a schematic cross-sectional view of the configuration of the electrostatic chuck 10 in a state where the substrate W is adsorbed and held. The electrostatic chuck 10 includes a dielectric substrate 100 and a base plate 200.

[0016] The dielectric substrate 100 is a substantially disk-shaped member made of a ceramic sintered body. The dielectric substrate 100 contains, for example, high-purity aluminum oxide (Al2O3), but may contain other materials. The purity, type, additives, etc. of the ceramics in the dielectric substrate 100 can be appropriately set in consideration of the plasma resistance, etc. required for the dielectric substrate 100 in a semiconductor manufacturing apparatus.

[0017] The upper surface 110 of the dielectric substrate 100 in FIG. 1 is the "placement surface" on which the substrate W is placed. Also, the lower surface 120 of the dielectric substrate 100 in FIG. 1 is the "bonding surface" that is bonded to the base plate 200 via the bonding layer 300. The viewpoint when viewing the electrostatic chuck 10 from the side of the surface 110 along the direction perpendicular to the surface 110 will also be hereinafter referred to as "top view".

[0018] An adsorption electrode 130 is embedded inside the dielectric substrate 100. The adsorption electrode 130 is a thin flat plate-shaped layer formed of a metal material such as tungsten, for example, and is arranged parallel to the surface 110. As the material of the adsorption electrode 130, in addition to tungsten, molybdenum, platinum, palladium, etc. may also be used. When a voltage is applied to the adsorption electrode 130 from the outside via a power supply path not shown, an electrostatic force is generated between the surface 110 and the substrate W, whereby the substrate W is adsorbed and held. As the configuration of the power supply path, various known configurations can be adopted. The adsorption electrode 130 may be provided only one as a so-called "single-pole" electrode as in this embodiment, or may be provided two as a so-called "bipolar" electrode. Incidentally, inside the dielectric substrate 100, in addition to the adsorption electrode 130, a heating part 431 and a bypass part 450 are also embedded, but these will be described later.

[0019] As shown in FIG. 1, a space SP is formed between the dielectric substrate 100 and the substrate W. When a process such as etching is performed in a semiconductor manufacturing apparatus, helium gas for temperature adjustment is supplied from the outside into the space SP through a gas hole (not shown in this embodiment). By interposing helium gas between the dielectric substrate 100 and the substrate W, the thermal resistance between the two is adjusted, and thereby the temperature of the substrate W is maintained at an appropriate temperature. Note that the gas for temperature adjustment supplied to the space SP may be a gas of a type different from helium.

[0020] A seal ring 111 and dots 112 are provided on the surface 110 which is the mounting surface, and the above-described space SP is formed around these.

[0021] The seal ring 111 is a wall that partitions the space SP at the outermost peripheral position. The upper end of the seal ring 111 is part of the surface 110 and abuts on the substrate W. Note that a plurality of seal rings 111 may be provided so as to divide the space SP. With such a configuration, the pressure of the helium gas in each space SP can be individually adjusted, and the surface temperature distribution of the substrate W during processing can be made closer to uniform.

[0022] The portion labeled with reference numeral "116" in FIG. 1 is the bottom surface of the space SP. Hereinafter, this portion will also be referred to as the "bottom surface 116". The seal ring 111, together with the dots 112 described below, is formed as a result of digging down a part of the surface 110 to the position of the bottom surface 116.

[0023] The dots 112 are circular protrusions protruding from the bottom surface 116. A plurality of dots 112 are provided and are arranged substantially evenly and dispersedly on the mounting surface of the dielectric substrate 100. The upper end of each dot 112 is part of the surface 110 and abuts on the substrate W. By providing a plurality of such dots 112, the deflection of the substrate W is suppressed.

[0024] Through holes 140 are formed in the dielectric substrate 100. The through holes 140 extend in a direction perpendicular to the mounting surface 110 and are formed to penetrate the dielectric substrate 100. The through holes 140 are formed as lift pin holes for inserting lift pins (not shown) provided in semiconductor manufacturing equipment. A total of three through holes 140 are formed, and they are arranged so as to be equally spaced at 120 degrees when viewed from above, but only one of them is shown in Figure 1. The substrate W is attached to and detached from the surface 110 of the dielectric substrate 100 by the lift pins that move up and down through the through holes 140. The inner diameter of the through holes 140 is constant throughout and does not change with height.

[0025] The base plate 200 is a roughly disc-shaped member that supports the dielectric substrate 100. The base plate 200 is made of a metallic material such as aluminum. Of the base plate 200, the upper surface 210 in Figure 1 is the "bonded surface" which is bonded to the dielectric substrate 100 via the bonding layer 300.

[0026] The bonding layer 300 is a layer provided between the dielectric substrate 100 and the base plate 200, and it bonds the two together. The bonding layer 300 is made by curing an adhesive made of an insulating material. In this embodiment, a silicone adhesive is used as the adhesive. However, the bonding layer 300 may be made by curing another type of adhesive. In any case, it is preferable to use a material with the highest possible thermal conductivity for the bonding layer 300 so that the thermal resistance between the dielectric substrate 100 and the base plate 200 is reduced.

[0027] A refrigerant channel 250 for circulating refrigerant is formed inside the base plate 200. When etching or other processes are performed in the semiconductor manufacturing equipment, refrigerant is supplied from the outside to the refrigerant channel 250, thereby cooling the base plate 200. During processing, the heat generated in the substrate W is transferred to the refrigerant via the helium gas in the space SP, the dielectric substrate 100, and the base plate 200, and is discharged to the outside together with the refrigerant. The supply and discharge of refrigerant to and from the refrigerant channel 250 is performed through an opening (not shown) formed on the surface 220 of the base plate 200 opposite to the surface 210.

[0028] In the base plate 200, through-holes 240 are formed at positions that overlap with the through-holes 140 when viewed from above. The through-holes 240 extend in a direction perpendicular to the mounting surface 110 and are formed to penetrate the base plate 200. The through-holes 240, along with the aforementioned through-holes 140, are formed as lift pin holes for inserting lift pins (not shown) provided in semiconductor manufacturing equipment. In Figure 1, only one of the three through-holes 240 is shown.

[0029] An insulating film may be formed on the surface of the base plate 200. As the insulating film, for example, an alumina film formed by thermal spraying can be used. By covering the surface of the base plate 200 with an insulating film, the dielectric strength of the base plate 200 can be increased.

[0030] The configuration of the heat-generating section 431 and the bypass section 450 provided inside the dielectric substrate 100 will now be described.

[0031] The heating element 431 functions as a built-in heater for heating the dielectric substrate 100. The heating element 431 is a linearly routed conductor that generates heat when power is supplied from an external source. The heating element 431 is routed along a plane parallel to the surface 110 at a height position that is on the surface 120 side (downward in Figure 1) of the adsorption electrode 130.

[0032] The dielectric substrate 100 is divided into multiple non-overlapping regions when viewed from above, and one heating element 431 is routed through each region. In other words, the dielectric substrate 100 has multiple heating elements 431 embedded in the regions, corresponding to the number of regions. By individually adjusting the amount of heat generated in each heating element 431, the in-plane temperature distribution of the substrate W during processing can be made more uniform.

[0033] Figure 2 shows an example of the above-described division of the region in a top view. In this example, the dielectric substrate 100 is divided into a total of 24 regions HA. The linear heating elements 431 are routed individually within each region HA. In other words, a total of 24 heating elements 431 are provided in this embodiment.

[0034] Figure 3 shows an example of a heat-generating element 431 routed within a single region HA. Within each region HA, a single linear heat-generating element 431 is routed along a path that passes through almost the entire area equally.

[0035] Circular pad portions 432 and 433 are formed at each end of the heating element 431. The heating element 431 and the pad portions 432 and 433 are formed, for example, by screen printing a metal material such as tungsten. Note that the shape of the heating element 431 shown in Figure 3 is schematic and differs from the actual shape. The same applies to the positions of the pad portions 432 and 433.

[0036] Returning to Figure 1, let's continue the explanation. Multiple bypass sections 450 are provided inside the dielectric substrate 100 as electrical circuits for supplying power to each of the heat-generating sections 431. Each bypass section 450 is a thin, flat layer made of a metallic material such as tungsten. The bypass sections 450 are provided inside the dielectric substrate 100 at a height that is on the surface 120 side of the heat-generating section 431. The bypass sections 450 are arranged along a plane parallel to the surface 110. The bypass sections 450 and the heat-generating sections 431 are electrically connected vias 401 (not shown in Figure 1, see Figure 4) provided inside the dielectric substrate 100. Each via 401 is an electrical circuit provided by filling a hole extending perpendicular to the surface 110 with a metal such as tungsten.

[0037] As shown in Figure 1, one end of a busbar 402 is electrically connected to the bypass section 450. External power is supplied to the bypass section 450 via this busbar 402. The busbar 402 is led to the outside through a through hole (not shown) formed in the base plate 200. A power supply terminal (not shown) connected to the bypass section 450 may be embedded in the surface 120 of the dielectric substrate 100. In this case, one end of the busbar 402 can be connected to the power supply terminal. Multiple busbars 402 are provided corresponding to the number of bypass sections 450, but only one is shown in Figure 1.

[0038] Figure 4 shows a schematic perspective view of the configuration of two regions HA, two heat-generating elements 431 routed between them, and bypass elements 450 connected to each heat-generating element 431. One of the two regions HA shown in Figure 4 will be referred to as "region HA1" below. The other region HA will be referred to as "region HA2" below. Note that the shapes of the heat-generating elements 431 shown in Figure 4 are schematic and differ from the actual shapes.

[0039] Multiple bypass sections 450 are provided inside the dielectric substrate 100 at the same height. In Figure 4, only three of the multiple bypass sections 450 are shown. Of the multiple bypass sections 450, the one labeled "451" in Figure 4 is positioned so as to overlap with only one region HA in a top view. In other words, it is individually positioned directly below each region HA. The portion of the bypass section 450 that is positioned in this manner will also be referred to as "bypass section 451" below.

[0040] Of the multiple bypass sections 450, the one labeled "452" in Figure 4 is positioned to overlap with both region HA1 and region HA2 in a top view. This portion of the bypass section 450 will also be referred to as "bypass section 452" below.

[0041] In the heat-generating section 431 located in region HA1, a pad portion 432 at one end of the heat-generating section 431 is electrically connected to a bypass portion 451 directly below it by a via 401. A pad portion 433 at the other end of the heat-generating section 431 is electrically connected to the bypass portion 452 by a via 401.

[0042] The same applies to the heat-generating section 431 located in region HA2, where a pad portion 432 at one end of the heat-generating section 431 is electrically connected to the bypass portion 451 directly below it by a via 401. A pad portion 433 at the other end of the heat-generating section 431 is electrically connected to the bypass portion 452 by a via 401.

[0043] Each bypass section 451 is electrically connected to a busbar 402 from below in Figure 4. A voltage is individually applied to each of these busbars 402 from an external DC power supply. A busbar 402 is also connected to the bypass section 452 from below in Figure 4. This busbar 402 is grounded. The DC power supply and grounding shown in Figure 4 are part of a temperature control circuit that is connected to the electrostatic chuck 10 from the outside.

[0044] As described above, each of the heat-generating units 431 provided in each region HA has one pad portion 432 connected to an individual DC power supply via a bypass portion 451, and the other pad portion 433 is grounded via a common bypass portion 452. Other heat-generating units 431 not shown in Figure 4 are also connected to a DC power supply, etc., in a similar configuration. With this configuration, it is possible to supply power to each of the multiple heat-generating units 431 individually and adjust the amount of heat generated in each part.

[0045] It is also possible to supply power to the heat-generating section 431 directly from the busbar 402 without going through the bypass section 450. However, by configuring the power supply to go through the bypass section 450 as in this embodiment, it becomes possible to increase the flexibility of the busbar 402's placement and to consolidate the grounded busbar 402 into one.

[0046] As shown in the example in Figure 4, the multiple bypass sections 450 include a bypass section 451 connected to a single heat-generating section 431 and a bypass section 452 connected to multiple heat-generating sections 431. Alternatively, each of the bypass sections 450 may be connected to a single heat-generating section 431. Furthermore, one bypass section 452 may be connected to three or more heat-generating sections 431.

[0047] The specific configuration in the vicinity of the through-hole 140 will be explained with reference to Figure 5. The adsorption electrode 130, the heating element 431, and the bypass element 450 are all conductive layers embedded inside the dielectric substrate 100. If such conductive layers were exposed on the inner surface of the through-hole 140, there is a possibility that discharge would occur from the exposed portion. For this reason, conductive layers such as the heating element 431 must be routed along paths that avoid the inner surface of the through-hole 140.

[0048] The "L1" shown in Figure 5 represents the shortest distance from the inner surface of the through-hole 140 to the heating element 431 when viewed from above. This shortest distance will also be referred to as "shortest distance L1" below. Since the shortest distance L1 is the shortest distance "when viewed from above," its size does not change depending on the direction of the cross-section.

[0049] The "L2" shown in Figure 5 represents the shortest distance from the inner surface of the through-hole 140 to the bypass section 450 when viewed from above. This shortest distance will also be referred to as "shortest distance L2" below. Since the shortest distance L2 is the shortest distance "when viewed from above," its size does not change depending on the direction of the cross-section. For the sake of explanation, Figure 5 shows an example where the shortest distance L1 and the shortest distance L2 appear in the same cross-section, but they generally appear in different cross-sections.

[0050] The "L3" shown in Figure 5 represents the shortest distance from the inner surface of the through-hole 140 to the adsorption electrode 130 when viewed from above. This shortest distance will also be referred to as "shortest distance L3" below. Since the shortest distance L3 is the shortest distance "when viewed from above," its size does not change depending on the direction of the cross-section. For the sake of explanation, Figure 5 shows an example where the shortest distance L1 and the shortest distance L3 appear in the same cross-section, but generally these appear in different cross-sections.

[0051] Incidentally, the heat-generating element 431 needs to be routed along a path that avoids the inner surface of the through-hole 140, as described above. For this reason, in the area of ​​the dielectric substrate 100 near the through-hole 140, there is a possibility of a localized temperature drop due to the heat-generating element 431 not being routed there. Also, in the area near the through-hole 140, heat dissipation by the base plate 200 directly below is difficult, so there is a possibility of a localized temperature rise. Thus, the area of ​​the dielectric substrate 100 near the through-hole 140 can be said to be an area that is prone to temperature singularities. In order to suppress localized temperature rises and falls, in the region HA including the area near the through-hole 140, it is necessary to bring the heat-generating element 431 as close to the through-hole 140 as possible and to precisely control the temperature of the region HA.

[0052] If the bypass section 450 is positioned as close to the through-hole 140 as the heat-generating section 431 (i.e., the shortest distance L2 = shortest distance L1), the Joule heat generated in the bypass section 450 may become a disturbance, potentially negatively affecting precise temperature control in the vicinity of the through-hole 140. As a result, the in-plane temperature distribution of the substrate W during processing may become more erratic.

[0053] Therefore, in the electrostatic chuck 10 according to this embodiment, the bypass section 450 and the like are arranged such that the shortest distance L2 from the inner surface of the through-hole 140 to the bypass section 450 is greater than the shortest distance L1 from the inner surface of the through-hole 140 to the heat-generating section 431.

[0054] In this configuration, the shortest distance L2 from the inner surface of the through-hole 140 to the bypass section 450 is longer than in conventional designs. This makes it possible to perform precise temperature control in the vicinity of the through-hole 140 of the dielectric substrate 100 while reducing the influence of Joule heating generated in the bypass section 450. As a result, variations in the in-plane temperature distribution of the substrate W during processing can be suppressed.

[0055] To achieve the above effects, it is preferable that the shortest distance L1 from the inner surface of the through hole 140 to the heating element 431 be set to a range of 0.5 mm or less. Furthermore, it is preferable that the shortest distance L2 from the inner surface of the through hole 140 to the bypass element 450 be set to a range of 0.5 mm or more.

[0056] In the electrostatic chuck 10 according to this embodiment, the adsorption electrode 130 and the like are arranged such that the shortest distance L3 from the inner surface of the through hole 140 to the adsorption electrode 130 is greater than the shortest distance L1 from the inner surface of the through hole 140 to the heat-generating part 431. With this configuration, it becomes possible to perform precise temperature control in the vicinity of the through hole 140 of the dielectric substrate 100 while also reducing the effect of Joule heating generated by the adsorption electrode 130. As a result, variations in the in-plane temperature distribution of the substrate W during processing can be further suppressed.

[0057] The second embodiment will now be described. The following will primarily focus on the differences from the first embodiment, while common points will be omitted as appropriate.

[0058] In the electrostatic chuck 10 according to this embodiment, a through hole 150 is formed in the dielectric substrate 100. Similar to the through hole 140, the through hole 150 extends in a direction perpendicular to the mounting surface 110 and is formed to penetrate the dielectric substrate 100. The through hole 150 is formed as a gas hole for supplying inert gas to the space SP. Figure 6 shows the configuration of the area near the through hole 150.

[0059] The through hole 150 has a first portion 151 and a second portion 152. The first portion 151 is the portion of the through hole 150 facing the surface 110 (the upper side in Figure 6), and the second portion 152 is the portion of the through hole 150 facing the surface 120 (the lower side in Figure 6). The inner diameter of the second portion 152 is larger than the inner diameter of the first portion 151. Therefore, the outer shape of the through hole 150 when viewed from above is equal to the outer shape of the second portion 152.

[0060] A porous member 160 is placed inside the second part 152. The porous member 160 is a roughly cylindrical porous body made of, for example, alumina, and is permeable throughout. By placing such a porous member 160 inside the through hole 150, it is possible to ensure the flow of helium gas through the through hole 150 while suppressing the occurrence of dielectric breakdown along the path through the through hole 150.

[0061] The "L11" shown in Figure 6 represents the shortest distance from the inner surface of the through-hole 150 to the heat-generating element 431 in a top view. This shortest distance will also be referred to as the "shortest distance L11" below. As mentioned earlier, the outer shape of the through-hole 150 in a top view is the same as the outer shape of the second part 152. Therefore, the shortest distance L11 in a top view is the same as the shortest distance from the inner surface of the second part 152 to the heat-generating element 431. Since the shortest distance L11 is the shortest distance "in a top view," its size does not change depending on the direction of the cross-section.

[0062] The "L12" shown in Figure 6 represents the shortest distance from the inner surface of the through hole 150 to the bypass section 450 in a top view. This shortest distance will also be referred to as the "shortest distance L12" below. For the same reasons mentioned earlier, the shortest distance L12 in a top view is equal to the shortest distance from the inner surface of the second section 152 to the bypass section 450. Since the shortest distance L12 is the shortest distance "in a top view," its size does not change depending on the direction of the cross-section. For the sake of explanation, Figure 6 shows an example where the shortest distance L11 and the shortest distance L12 appear in the same cross-section, but they generally appear in different cross-sections.

[0063] The "L13" shown in Figure 6 represents the shortest distance from the inner surface of the through-hole 150 to the adsorption electrode 130 in a top view. This shortest distance will also be referred to as "shortest distance L13" below. For the same reasons mentioned earlier, the shortest distance L13 in a top view is equal to the shortest distance from the inner surface of the second part 152 to the adsorption electrode 130. Since the shortest distance L13 is the shortest distance "in a top view," its magnitude does not change depending on the direction of the cross-section. For the sake of explanation, Figure 6 shows an example where the shortest distance L11, etc., and the shortest distance L13 appear in the same cross-section, but generally these appear in different cross-sections.

[0064] In the electrostatic chuck 10 according to this embodiment, similar to the first embodiment, the bypass section 450 and the like are arranged such that the shortest distance L12 from the inner surface of the through-hole 150 to the bypass section 450 is greater than the shortest distance L11 from the inner surface of the through-hole 150 to the heating section 431. Also, the adsorption electrode 130 and the like are arranged such that the shortest distance L13 from the inner surface of the through-hole 150 to the adsorption electrode 130 is greater than the shortest distance L11 from the inner surface of the through-hole 150 to the heating section 431. With this configuration, the same effects as those described in the first embodiment can be achieved.

[0065] The embodiments have been described above with reference to specific examples. However, this disclosure is not limited to these specific examples. Modifications made to these specific examples by those skilled in the art are also included within the scope of this disclosure, as long as they retain the features of this disclosure. The elements, their arrangement, conditions, shapes, etc., of each of the aforementioned specific examples are not limited to those illustrated and can be modified as appropriate. The elements of each of the aforementioned specific examples can be combined in different ways as appropriate, as long as no technical inconsistencies arise. [Explanation of symbols]

[0066] 10: Electrostatic Chuck 100: Dielectric substrate 110: Face 130: Adsorption electrode 140,150: Through hole 160: Porous material 431: Heat-generating part 450: Bypass section W: Circuit board

Claims

1. A dielectric substrate having a mounting surface on which an object to be adsorbed is placed, and having a through hole formed perpendicular to the aforementioned mounting surface, Multiple heating elements are routed linearly inside the dielectric substrate, The dielectric substrate is provided with an electrical circuit and includes a bypass section that is electrically connected to the heating section, When viewed from a direction perpendicular to the mounting surface, The shortest distance from the inner surface of the through hole to the heating element is greater than the shortest distance from the inner surface of the through hole to the heating element. The shortest distance from the inner surface of the through hole to the bypass portion is greater. Adsorption electrodes are provided inside the dielectric substrate. When viewed from a direction perpendicular to the mounting surface, The shortest distance from the inner surface of the through hole to the heating element is greater than the shortest distance from the inner surface of the through hole to the heating element. An electrostatic chuck characterized in that the shortest distance from the inner surface of the through hole to the adsorption electrode is greater than the shortest distance.

2. The electrostatic chuck according to claim 1, characterized in that the shortest distance from the inner surface of the through hole to the bypass portion is 0.5 mm or more.

3. The electrostatic chuck according to claim 1, characterized in that the shortest distance from the inner surface of the through hole to the heating element is 0.5 mm or less.

4. The electrostatic chuck according to claim 1, characterized in that a porous member is arranged inside the through hole.

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