Electrostatic chuck

Abstract

To provide an electrostatic chuck which prevents deposition of particles in a seal ring portion while effectively controlling the pressure of gas in each region.SOLUTION: An electrostatic chuck includes: a base plate; a ceramic dielectric substrate 11 provided on the base plate and having a first main surface 11a exposed to the outside and a second main surface 11b opposite to the first main surface. The first main surface 1 includes at least a first region 101 and a second region 102 adjacent to the first region. At least one first gas introduction hole 15 connected to a gas supply passage, via a plurality of first grooves 14a, 14b and a first porous portion 90, is provided in the first region. The plurality of first grooves include a first boundary groove. At least one second gas introduction hole 15 connected to the gas supply passage, via a plurality of second grooves 14a, 14b and the first porous portion 90, is provided in the second region. The plurality of second grooves include a second boundary groove, and a groove end-to-end length between the first boundary groove and the second boundary groove is equal to or less than 60 mm.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] Aspects of the present invention relate to an electrostatic chuck. [Background technology]

[0002] An electrostatic chuck has a ceramic dielectric substrate made of, for example, alumina and an electrode provided inside the ceramic dielectric substrate. When power is applied to the electrode, an electrostatic force is generated. The electrostatic chuck attracts an object such as a silicon wafer using the generated electrostatic force. In such an electrostatic chuck, an inert gas such as helium (He) (hereinafter simply referred to as gas) is flowed between the front surface of the ceramic dielectric substrate and the back surface of the object to control the temperature of the object.

[0003] For example, in apparatuses that process substrates, such as CVD (Chemical Vapor Deposition) apparatuses, sputtering apparatuses, ion implantation apparatuses, etching apparatuses, etc., the temperature of the substrate may rise during processing. Therefore, in electrostatic chucks used in such apparatuses, a gas is passed between the ceramic dielectric substrate and the substrate, and the gas is brought into contact with the substrate, thereby dissipating heat from the substrate.

[0004] Furthermore, during processing, a temperature distribution occurs within the surface of the object. In this case, if the gas pressure is increased, the amount of heat dissipated from the object increases, and the temperature of the object can be lowered. Therefore, the surface of the ceramic dielectric substrate facing the object is divided into multiple regions, and the gas pressure in each region is changed to control the temperature within the surface of the object.

[0005] For example, a technique has been proposed in which a seal ring is provided between each region in order to control the gas pressure in each region (see, for example, Patent Document 1). In this case, in order to control the gas pressure in each region, it is preferable to hermetically separate each region with a seal ring. However, this makes it easier for particles generated during the wafer processing to accumulate in the seal ring, which can cause problems such as defects in that region.

[0006] A technique has also been proposed in which a small gap is provided between the top of the seal ring and the object, and the gas pressure in each region is controlled (see Patent Document 2). Even in this case, the problem of particles easily accumulating in the seal ring portion has not been solved. Therefore, there has been a demand for the development of a technology that can effectively control the gas pressure in each region while suppressing particle accumulation in the seal ring portion. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-119708 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-129547 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made based on the recognition of the above-mentioned problems, and has an object to provide an electrostatic chuck that can effectively control the gas pressure in each region while suppressing particle accumulation in the seal ring portion. [Means for solving the problem]

[0009] A first invention includes a base plate and a ceramic dielectric substrate provided on the base plate, the ceramic dielectric substrate having a first main surface exposed to the outside and a plurality of dots provided on the first main surface, the first main surface including at least a first region (region 101) and a second region (region 102) adjacent to the first region, the first region of the first main surface being provided with a plurality of first grooves (grooves 14a, 14b) and at least one first gas introduction hole (gas introduction hole 15) connected to at least one of the plurality of first grooves, the plurality of first grooves being provided closest to a first boundary (boundary 102a) between the first region and the second region and including a first boundary groove (groove 14a) extending along the first boundary, The electrostatic chuck is characterized in that the second region of one main surface is provided with a plurality of second grooves (grooves 14a, 14b) and at least one second gas introduction hole (gas introduction hole 15) connected to at least one of the plurality of second grooves, the plurality of second grooves are provided closest to the first boundary and include a second boundary groove extending along the first boundary, an object is placed on the plurality of dots so that the object is supported by the dots, a space is formed between the object and the first main surface, gas supplied to one of the first boundary groove and the second boundary groove is supplied to the other via the space, and a distance between groove ends of the first boundary groove and the second boundary groove (groove 14a) is greater than 0 mm and not greater than 60 mm.

[0010] This electrostatic chuck does not have a seal ring disposed between each region to control the gas pressure in each region, as in conventional electrostatic chucks. That is, when the target object W is placed on the electrostatic chuck, a single closed space is formed between the target object W and the ceramic dielectric substrate (first region and second region). This solves the problem of particles accumulating in the seal ring area. On the other hand, simply omitting the seal ring makes it difficult to divide the gas pressure between each region, resulting in reduced gas pressure controllability. Therefore, in the present invention, in addition to eliminating the seal ring, the distance between the groove ends of the first boundary groove and the second boundary groove is designed to be greater than 0 mm and equal to or less than 60 mm. Furthermore, with this electrostatic chuck, the area where the gas pressure changes near the boundary between regions can be reduced, thereby increasing the area where the intended gas pressure is maintained, thereby effectively controlling the gas pressure in each region while solving the problem of particle deposition.

[0011] A second invention is an electrostatic chuck according to the first invention, characterized in that the distance between the groove ends of the first boundary groove and the second boundary groove is greater than 0 mm and not more than 20 mm.

[0012] This electrostatic chuck allows for more effective control of the gas pressure in each region.

[0013] A third invention is an electrostatic chuck according to the first or second invention, characterized in that at least a portion of the first gas introduction hole overlaps with the first boundary groove when projected onto a plane perpendicular to a first direction extending from the base plate toward the ceramic dielectric substrate.

[0014] In this electrostatic chuck, the first boundary groove and the first gas inlet hole are directly connected to each other, which provides excellent gas controllability, thereby making it possible to further reduce the area where gas pressure changes near the boundary between regions.

[0015] A fourth invention is an electrostatic chuck according to any one of the first to third inventions, characterized in that, when projected onto a plane perpendicular to a first direction extending from the base plate toward the ceramic dielectric substrate, at least a portion of the second gas introduction hole overlaps with the second boundary groove.

[0016] According to this electrostatic chuck, the area where the gas pressure changes can be made smaller near the boundary between the regions.

[0017] A fifth invention is an electrostatic chuck according to any one of the first to fourth inventions, characterized in that the angle formed by the line connecting the center of the first gas introduction hole and the center of the second gas introduction hole and the first boundary is less than 90°.

[0018] This electrostatic chuck allows the boundary grooves to be closer to each other, thereby reducing the area where the gas pressure changes, and therefore increasing the area where the intended gas pressure is achieved.

[0019] A sixth invention is an electrostatic chuck according to any one of the first to fourth inventions, characterized in that the angle formed between the first boundary and a line connecting the center of the first gas introduction hole and the center of the second gas introduction hole is 90°.

[0020] This electrostatic chuck makes it easier to maintain the pressure in each region at a targeted pressure.

[0021] A seventh invention is an electrostatic chuck according to any one of the first to sixth inventions, characterized in that the plurality of first grooves further include at least one first region groove (groove 14b) different from the first boundary groove, and a lift pin hole provided in the first main surface, and the distance between the lift pin hole and the first boundary groove is greater than the distance between the lift pin hole and the first region groove closest to the lift pin hole.

[0022] This electrostatic chuck can reduce pressure variations within the region. [Effects of the Invention]

[0023] According to an aspect of the present invention, an electrostatic chuck is provided that can effectively control the gas pressure in each region while suppressing particle accumulation in the seal ring portion. [Brief explanation of the drawings]

[0024] [Figure 1]FIG. 1 is a schematic cross-sectional view illustrating an electrostatic chuck according to an embodiment of the present invention. [Figure 2] 3 is a schematic cross-sectional view illustrating a ceramic dielectric substrate, an electrode, and a first porous portion. FIG. [Figure 3] 1A is a schematic cross-sectional view illustrating the arrangement of grooves and gas introduction holes according to a comparative example, and FIG. 1B is a schematic cross-sectional view illustrating an example of the arrangement of grooves and gas introduction holes according to the present embodiment. [Figure 4] FIG. 10 is a graph showing the pressure in the region and the pressure at the boundary between the regions obtained by simulation. [Figure 5] FIG. 10 is a graph illustrating the effect of boundary groove spacing. [Figure 6] 10A is a graph illustrating the effect of boundary groove spacing using the "gradient deviation rate," and FIG. 10B is a graph explaining the "gradient deviation rate." [Figure 7] FIG. 6(b) is an enlarged view of part H in FIG. [Figure 8] FIG. 10 is a graph illustrating the effect of the number of second grooves (grooves 14a, 14b). [Figure 9] 10A is a schematic cross-sectional view illustrating the arrangement of gas introduction holes, and FIG. 10B is a schematic cross-sectional view illustrating the arrangement of gas introduction holes according to another embodiment. [Figure 10] (a) and (b) are graphs showing the pressure in the region and the pressure at the boundary between the regions obtained by simulation. [Figure 11] FIG. 10 is a schematic plan view of a ceramic dielectric substrate according to another embodiment. [Figure 12] 1A is a schematic plan view illustrating the arrangement of grooves according to a comparative example, and FIG. 1B is a schematic plan view illustrating the arrangement of grooves according to a comparative example. [Figure 13] FIG. 10 is a graph illustrating the pressure change at the center of the substrate. [Figure 14] 10(a) to 10(c) are schematic diagrams illustrating the configuration of the groove 14c. [Figure 15]FIG. 10 is a schematic plan view of a ceramic dielectric substrate according to another embodiment. [Figure 16] 1 is a schematic diagram illustrating a processing apparatus according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, like components are designated by like reference numerals and detailed descriptions thereof will be omitted where appropriate. In each figure, the direction from the base plate 50 to the ceramic dielectric substrate 11 is the Z direction, one of the directions approximately perpendicular to the Z direction is the Y direction, and the direction approximately perpendicular to the Z direction and the Y direction is the X direction.

[0026] (electrostatic chuck) FIG. 1 is a schematic cross-sectional view illustrating an electrostatic chuck 1 according to the present embodiment. FIG. 2 is a schematic cross-sectional view illustrating the ceramic dielectric substrate 11, the electrode 12, and the first porous portion 90. As shown in FIG. As shown in FIG. 1, the electrostatic chuck 1 may include a ceramic dielectric substrate 11, an electrode 12, a first porous portion 90, a base plate 50, and a second porous portion .

[0027] As shown in FIGS. 1 and 2, the ceramic dielectric substrate 11 can be, for example, a flat plate-shaped member made of sintered ceramic. For example, the ceramic dielectric substrate 11 can contain aluminum oxide (Al2O3). For example, the ceramic dielectric substrate 11 can be formed using high-purity aluminum oxide. The concentration of aluminum oxide in the ceramic dielectric substrate 11 can be, for example, 99 atomic percent (at %) or more and 100 atomic % or less. The use of high-purity aluminum oxide can improve the plasma resistance of the ceramic dielectric substrate 11. The porosity of the ceramic dielectric substrate 11 can be, for example, 1% or less. The density of the ceramic dielectric substrate 11 can be, for example, 4.2 g / cm 3 It can be said that:

[0028] The ceramic dielectric substrate 11 has a first main surface 11a on which an object W to be attracted is placed, and a second main surface 11b opposite to the first main surface 11a. The first main surface 11a is the surface exposed to the outside of the electrostatic chuck 1. The object W can be, for example, a semiconductor substrate such as a silicon wafer, a glass substrate, or the like.

[0029] A plurality of dots 13 are provided on the first main surface 11a of the ceramic dielectric substrate 11. The object W is placed on the plurality of dots 13 and is supported by the plurality of dots 13. The provision of the plurality of dots 13 forms a space between the back surface of the object W placed on the electrostatic chuck 1 and the first main surface 11a. By appropriately selecting the height, number, area ratio, shape, etc. of the dots 13, it is possible to, for example, make particles adhere to the object W in a preferable state. For example, the height (dimension in the Z direction) of the plurality of dots 13 can be set to 1 μm or more and 100 μm or less, preferably 1 μm or more and 30 μm or less, and more preferably 5 μm or more and 15 μm or less.

[0030] A plurality of grooves 14a and 14b are provided on the first main surface 11a of the ceramic dielectric substrate 11. The plurality of grooves 14a and 14b are open to the first main surface 11a of the ceramic dielectric substrate 11. The width of the grooves 14a (dimension in the X or Y direction) can be, for example, 0.1 mm to 2.0 mm, preferably 0.1 mm to 1.0 mm, and more preferably 0.2 mm to 0.5 mm. The depth of the grooves 14a (dimension in the Z direction) can be, for example, 10 μm to 300 μm, preferably 10 μm to 200 μm, and more preferably 50 μm to 150 μm. The width of the grooves 14b (dimension in the X or Y direction) can be, for example, 0.1 mm to 1.0 mm. The depth (dimension in the Z direction) of the groove 14b can be, for example, 0.1 mm or more and 2.0 mm or less, preferably 0.1 mm or more and 1.0 mm or less, and more preferably 0.2 mm or more and 0.5 mm or less.

[0031] The ceramic dielectric substrate 11 is provided with a plurality of gas introduction holes 15. One end of each of the plurality of gas introduction holes 15 can be connected to the groove 14a. The other end of each of the plurality of gas introduction holes 15 can be connected to a gas supply path 53 (described later) via a first porous portion 90. The gas introduction holes 15 are provided from the second main surface 11b to the first main surface 11a. That is, the gas introduction holes 15 extend in the Z direction between the second main surface 11b side and the first main surface 11a side, penetrating the ceramic dielectric substrate 11. The diameter of the gas introduction holes 15 can be, for example, 0.05 mm or more and 0.5 mm or less. The grooves 14a, 14b and the gas introduction holes 15 will be described in detail later.

[0032] The electrode 12 is provided inside the ceramic dielectric substrate 11. The electrode 12 is provided between the first main surface 11a and the second main surface 11b of the ceramic dielectric substrate 11. The electrode 12 may be shaped, for example, as a thin film along the first main surface 11a and the second main surface 11b of the ceramic dielectric substrate 11. The electrode 12 is an attraction electrode for attracting and holding the object W. The electrode 12 may be of either a monopolar or bipolar type. The electrode 12 illustrated in FIG. 1 is of a bipolar type, and two electrodes 12 are provided on the same surface.

[0033] The electrode 12 is provided with a connecting portion 20. The electrode 12 and the connecting portion 20 can be made of a conductive material such as metal. The end of the connecting portion 20 opposite the electrode 12 side can be exposed on the second main surface 11b side of the ceramic dielectric substrate 11. The connecting portion 20 can be, for example, a via (solid type) or a via hole (hollow type) that is electrically connected to the electrode 12. The connecting portion 20 may also be a metal terminal connected by an appropriate method such as brazing.

[0034] A power source 210 is electrically connected to the electrode 12 via a connection part 20. When a predetermined voltage is applied to the electrode 12, an electric charge can be generated in a region of the electrode 12 on the first main surface 11a side. As a result, the object W is attracted and held on the first main surface 11a side of the ceramic dielectric substrate 11 by electrostatic force.

[0035] The first porous portion 90 is provided inside the ceramic dielectric substrate 11. The first porous portion 90 can be provided, for example, in a position between the base plate 50 and the first main surface 11a of the ceramic dielectric substrate 11 in the Z direction, facing the gas supply path 53. For example, the first porous portion 90 can be provided in the gas introduction hole 15 of the ceramic dielectric substrate 11. For example, the first porous portion 90 is inserted into a part of the gas introduction hole 15.

[0036] In the case of the first porous portion 90 illustrated in FIGS. 1 and 2, the first porous portion 90 is provided in a portion of the gas introduction hole 15 on the second main surface 11b side. One end of the first porous portion 90 is exposed to the second main surface 11b of the ceramic dielectric substrate 11. The other end of the first porous portion 90 is located between the first main surface 11a and the second main surface 11b. The other end of the first porous portion 90 may be exposed at the bottom surface of the groove 14a. Alternatively, both ends of the first porous portion 90 may be located between the first main surface 11a and the second main surface 11b.

[0037] The material of the first porous portion 90 can be, for example, an insulating ceramic. The first porous portion 90 contains, for example, at least one of aluminum oxide (Al2O3), titanium oxide (TiO2), and yttrium oxide (Y2O3). In this way, the first porous portion 90 can have high dielectric strength and high rigidity.

[0038] In this case, the purity of the aluminum oxide of the ceramic dielectric substrate 11 can be made higher than the purity of the aluminum oxide of the first porous portion 90. In this way, it is possible to ensure the performance of the electrostatic chuck 1, such as plasma resistance, and also to ensure the mechanical strength of the first porous portion 90. As an example, by adding a small amount of additive to the first porous portion 90, sintering of the first porous portion 90 is promoted, making it possible to control the pores and ensure the mechanical strength.

[0039] For example, the purity of ceramics such as aluminum oxide can be measured by X-ray fluorescence analysis, ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry), or the like.

[0040] 1, the base plate 50 supports, for example, a ceramic dielectric substrate 11. The ceramic dielectric substrate 11 can be glued onto the base plate 50. The adhesive can be, for example, a silicone adhesive.

[0041] The base plate 50 is made of, for example, metal. The base plate 50 is divided into an upper portion 50a and a lower portion 50b, each made of, for example, aluminum, and a connection path 55 is provided between the upper portion 50a and the lower portion 50b. One end of the connection path 55 is connected to the input path 51, and the other end of the connection path 55 is connected to the output path 52.

[0042] The base plate 50 also serves to adjust the temperature of the dielectric substrate 11. For example, when cooling the dielectric substrate 11, a cooling medium flows in through the input path 51, passes through the connection path 55, and flows out through the output path 52. This allows the cooling medium to absorb heat from the base plate 50 and cool the ceramic dielectric substrate 11 attached thereto. Note that when keeping the dielectric substrate 11 warm, it is also possible to flow a heat-retaining medium into the connection path 55. If the temperature of the dielectric substrate 11 can be controlled, it becomes easier to control the temperature of the object W attracted and held on the dielectric substrate 11.

[0043] Gas is supplied to the plurality of grooves 14a, 14b. The supplied gas comes into contact with the object W, thereby controlling the temperature of the object W. In this case, if the temperature of the base plate 50 can be controlled, the range of temperature control by the gas supplied to the grooves 14a, 14b can be narrowed. For example, the temperature of the object W can be roughly controlled by the base plate 50, and the temperature of the object W can be precisely controlled by the gas supplied to the grooves 14a, 14b.

[0044] A plurality of gas supply paths 53 may be provided in the base plate 50. The gas supply paths 53 may be provided so as to penetrate the base plate 50. Alternatively, the gas supply paths 53 may not penetrate the base plate 50, but may branch off from another gas supply path 53 and extend to the ceramic dielectric substrate 11 side.

[0045] The gas supply path 53 is connected to the gas introduction hole 15. That is, the gas that has flowed into the gas supply path 53 passes through the gas supply path 53 and then flows into the gas introduction hole 15.

[0046] The gas that has flowed into the gas inlet hole 15 passes through the gas inlet hole 15 and then flows into the groove 14a connected to the gas inlet hole 15. This allows the object W to be directly cooled by the gas.

[0047] The second porous portion 70 can be provided between the first porous portion 90 and the gas supply path 53 in the Z direction. For example, the second porous portion 70 is fitted into the end face of the base plate 50 facing the ceramic dielectric substrate 11. As shown in FIG. 1 , for example, a counterbore 53a can be provided on the end face of the base plate 50 facing the ceramic dielectric substrate 11, and the second porous portion 70 can be fitted into the counterbore 53a. The counterbore 53a is connected to the gas supply path 53. The second porous portion 70 can be provided so as to face the first porous portion 90.

[0048] Next, the multiple grooves 14a, 14b and the multiple gas introduction holes 15 will be further described. As described above, the temperature of the object W can be controlled by the gas supplied to the multiple grooves 14a, 14b. During processing of the object W, a temperature distribution may occur within the surface of the object W. For example, low-temperature regions and high-temperature regions may occur within the surface of the object W. In this case, if the pressure of the gas in contact with the high-temperature region is made higher than the pressure of the gas in contact with the low-temperature region, the amount of heat dissipated from the high-temperature region increases, thereby controlling the temperature of the object W and suppressing the occurrence of a temperature distribution within the surface of the object W.

[0049] For example, the first main surface 11a side of the ceramic dielectric substrate 11 can be divided into multiple regions, and the in-plane temperature of the object W can be controlled by changing the pressure of the gas supplied to the multiple regions. In this case, in order to control the gas pressure in each region, a seal ring may be provided between each region to separate them. In this example, the top of the seal ring is brought into contact with the surface of the object W on the first main surface 11a side. In this way, it is possible to almost completely eliminate the flow of gas between the regions, thereby effectively controlling the gas pressure in each region.

[0050] However, when a seal ring is provided, particles generated during the wafer processing process tend to accumulate in the seal ring area, which may cause problems such as defects in that area.

[0051] Therefore, in the present invention, a seal ring for separating the regions is not provided, and the arrangement of the grooves 14a and 14b is devised. That is, when the object W is placed, a closed space is formed between the object W and the ceramic dielectric substrate 11 (for example, the regions 101 and 102). According to the present invention, it is possible to effectively control the pressure within the regions, even without a seal ring. Furthermore, in the present invention, it is sufficient to be able to effectively control the gas pressure in each region without substantially providing a seal ring, and partial or local provision of a seal ring is not precluded. In other words, as long as the effect of effectively controlling the gas pressure in each region can be achieved without substantially providing a seal ring, partial or local provision of a seal ring may be permitted. FIG. 3A is a schematic cross-sectional view illustrating the arrangement of the grooves 14 and the arrangement of the gas introduction holes 15 according to a comparative example. 3(a), the grooves 14 are provided at equal intervals in the X direction. That is, the distance L23 between the groove ends in the X direction is the same.

[0052] In this specification, the groove end distance refers to the shortest distance between the inner wall of one groove on the other groove side and the inner wall of the other groove on the one groove side when there are two adjacent grooves. In this case, if the groove end distance between the two grooves varies, the shortest distance can be used as the groove end distance.

[0053] In addition, in the X direction, the region 100a is adjacent to the region 100b1, and the region 100a is adjacent to the region 100b2. In the example shown in Figure 3(a), gas introduction holes 15 are connected to two grooves 14 provided on either side of the boundary between the region 100a and the region 100b1.

[0054] The pressure of the gas supplied to the grooves 14 provided in the region 100a is P1, the pressure of the gas supplied to the grooves 14 provided in the region 100b1 is P2, and the pressure of the gas supplied to the grooves 14 provided in the region 100b2 is P3.

[0055] FIG. 3(b) is a schematic cross-sectional view for illustrating an example of the arrangement of the grooves 14a and 14b and the arrangement of the gas introduction holes 15 according to the present embodiment. The groove 14a is a boundary groove provided across the boundary between different regions, and the groove 14b is an in-region groove provided within the region other than the groove 14a. In FIG. 3(b), the distance between the groove end portions (boundary groove interval) of the two grooves 14a (boundary grooves) provided across the boundary between the region 100a and the regions 100b1 and 100b2 in the X direction is denoted as L21, and the distance between the groove end portions (in-region groove interval) of the groove 14a (boundary groove) and the groove 14b (in-region groove) provided within the region 100a adjacent to this boundary groove 14a is denoted as L22. In this case, L21 < L22. Also, the distance between the groove end portions of the groove 14a (boundary groove) and the groove 14b other than the groove 14a provided within the regions 100b1 and 100b2 adjacent to this boundary groove 14a is denoted as L24, respectively. Further, the pressure of the gas supplied to the groove 14a provided in the region 100a through the gas introduction hole 15 is denoted as P1, and the pressure of the gas supplied to the groove 14a provided in the region 100b1 is denoted as P2.

[0056] FIG. 4 is a graph showing the pressures of the region 100a, the regions 100b1 and 100b2, and the pressure at the boundary between the region 100a and the regions 100b1 and 100b2 obtained by simulation. In the simulation, it is assumed that there is an object W supported by the dots 13 above the first main surface 11a of the ceramic dielectric substrate 11. A in FIG. 4 is an example in which the arrangement of the groove 14, the arrangement of the gas introduction hole 15, and the boundary groove interval and the in-region groove interval illustrated in FIG. 3(a) are equal. B in FIG. 4 is an example in which the arrangement of the grooves 14a and grooves 14b, the arrangement of the gas introduction holes 15, and the boundary groove interval illustrated in FIG. 3(b) are smaller than the in-region groove interval. In any of the examples, no seal ring is provided between the regions. Also, in the simulation, P1 = 3 × P2, the groove end portion distance L21 is 5 mm, the groove end portion distance L22 is 20 mm, and the groove end portion distance L23 is 15 mm. The dimension of the region 100a in the X direction is 50 mm.

[0057] 4, when the boundary groove spacing and the intra-region groove spacing are equal (case A), the region where the gas pressure changes becomes larger near the boundaries between region 100a and regions 100b1 and 100b2. In contrast, when the boundary groove spacing is smaller than the intra-region groove spacing (case B), the region where the gas pressure changes near the boundaries between region 100a and regions 100b1 and 100b2 can be made smaller than in case A. That is, in each of region 100a, region 100b1, and 100b2, the region where the intended gas pressure is achieved can be made larger, thereby improving the uniformity of the gas pressure within the region.

[0058] As described above, by devising the arrangement of the grooves 14a and 14b, the temperature of the object W can be controlled by the gas pressure even when no seal ring is provided between the regions. Therefore, if the uniformity of the gas pressure within the region can be increased, the temperature of the object W in the portion corresponding to the region can be more effectively controlled. Furthermore, the occurrence of in-plane temperature distribution of the object W can be suppressed.

[0059] Furthermore, according to the findings of the present inventors, it is preferable that the gas introduction hole 15 is connected to at least one of the two boundary grooves 14a provided on either side of the boundary, since this can provide the aforementioned effects.

[0060] In this case, there is a gap between the first main surface 11a and the object W that is the height of the dots 13, and therefore the gas supplied to the groove 14a connected to the gas inlet hole 15 is supplied to the groove 14b and other grooves 14a through the gap. That is, in each region, the gas is supplied to the space formed between the back surface of the object W and the first main surface 11a including the grooves 14a and 14b.

[0061] Furthermore, as illustrated in FIG. 3(b), when gas introduction holes 15 are connected to two grooves 14a provided on either side of the boundary, the change in gas pressure at the boundary between the regions can be made more pronounced, and the temperature of the object W can be controlled more effectively. Furthermore, it is possible to more effectively prevent the temperature of the object W from being distributed in its surface.

[0062] FIG. 5 is a graph illustrating the effect of boundary groove spacing. The boundary groove spacing on the horizontal axis is the distance between the groove ends of two grooves (boundary grooves) that are provided on either side of the boundary between adjacent regions. The effect of the boundary groove spacing is the effect of the boundary groove spacing itself, and can be applied to, for example, the distance L23 illustrated in Figure 3(a) or the distance L21 illustrated in Figure 3(b). The deviation rate on the vertical axis indicates the degree to which the average pressure in each region deviates from the set pressure (intended pressure). The larger the deviation rate, the greater the difference between the average pressure in each region and the intended pressure. FIG. 5 shows the deviation rate obtained by simulation when the pressure P1 in the region 100a in FIGS. 3(a) and 3(b) is set to 20 Torr (2666.4 Pa) and the pressure P3 in the region 100b2 is set to 60 Torr (7999.2 Pa).

[0063] As can be seen from Figure 5, when the boundary groove spacing, which is the distance between the groove ends of the boundary grooves, is greater than 0 mm and less than 60 mm, preferably greater than 0 mm and less than 20 mm, the deviation rate increases almost linearly. When the boundary groove spacing exceeds 60 mm, the deviation rate increases exponentially. This means that when the boundary groove spacing is 60 mm or less, preferably less than 20 mm, the increase in the deviation rate can be suppressed, and ultimately the average pressure in each region becomes closer to the intended pressure. As mentioned above, the effect of the boundary groove spacing is the effect of the boundary groove spacing itself, so by appropriately combining the arrangement of the grooves 14a and 14b mentioned above, the arrangement of the gas introduction hole 15 mentioned above (connecting the gas introduction hole 15 to the boundary groove), and groove 14c described below, it is possible to more effectively control the gas pressure in each region while effectively suppressing the accumulation of particles in the seal ring portion.

[0064] FIG. 6(a) is a graph illustrating the effect of the boundary groove interval using the "slope deviation rate." FIG. 6(b) is a graph for explaining the "slope deviation rate." FIG. 7 is an enlarged view of part H in FIG. 6(a). If the pressure in the first region and the pressure in the second region are ideally separated, the pressure distribution at the first boundary between the first and second regions is thought to be distributed on a straight line (change linearly), as shown in Figure 6(b). Therefore, by arithmetically calculating the slope from the pressure distribution between the regions obtained by analysis and determining the deviation rate (slope deviation rate) from the ideal slope, the effect of the boundary groove spacing can be evaluated.

[0065] As can be seen from Figure 6(a), when the boundary groove interval, which is the distance between the groove ends of the boundary grooves, is greater than 0 mm and less than or equal to 60 mm, the slope deviation rate increases almost linearly. When the boundary groove interval exceeds 60 mm, the slope deviation rate increases exponentially. This means that when the boundary groove interval is 60 mm or less, the increase in the slope deviation rate can be suppressed, and ultimately, the average pressure in each region will be closer to the intended pressure. Furthermore, as can be seen from Figure 7, if the boundary groove interval, which is the distance between the groove ends of the boundary grooves, is greater than 0 mm and less than or equal to 20 mm, the slope deviation rate can be made even closer to linearity. This means that if the boundary groove interval is less than or equal to 20 mm, the increase in the slope deviation rate can be further suppressed, and ultimately the average pressure in each region becomes even closer to the intended pressure.

[0066] FIG. 8 is a graph illustrating the effect of the number of second grooves (grooves 14a, 14b (radial grooves)). As can be seen from Figure 8, if at least two second grooves are provided in the second region, the deviation rate can be significantly reduced. That is, the pressure at the first boundary (boundary 102a) between the first region (region 101) and the second region (region 102) can be made closer to the average value of the pressure in the first region and the pressure in the second region. This makes it easier to maintain the pressure in each region at the desired pressure.

[0067] According to the findings of the inventors, if the boundary groove occupancy ratio is greater than the intra-region groove occupancy ratio, the effect illustrated in FIG. 4 can be obtained. That is, if the boundary groove occupancy ratio is greater than the intra-region groove occupancy ratio, the region where the gas pressure changes near the boundary can be reduced. Therefore, the region where the intended gas pressure is achieved can be increased, thereby effectively controlling the temperature of the object W. Furthermore, the occurrence of an in-plane temperature distribution of the object W can be suppressed.

[0068] FIG. 9( a ) is a schematic cross-sectional view illustrating the arrangement of the gas introduction holes 15 . In FIG. 9(a), region 100a and region 100b1 are adjacent to each other in the X direction, and region 100a and region 100b2 are adjacent to each other. Two grooves 14a (boundary grooves) are provided on either side of the boundary between region 100a and regions 100b1 and 100b2 in the X direction. Grooves 14b (intra-region grooves) are provided inside region 100a and inside regions 100b1 and 100b2. In region 100a, a gas introduction hole 15 is connected to groove 14a on the region 100b1 side, but not to groove 14a on the region 100b2 side. In region 100b1, a gas introduction hole 15 is connected to groove 14a on the region 100a side. In region 100b2, a gas introduction hole 15 is connected to groove 14a on the region 100a side. That is, in the region 100a, the gas introduction hole 15 is connected to only one of the grooves 14a. The pressure of the gas supplied to the grooves 14a provided in the region 100a is P1, and the pressure of the gas supplied to the grooves 14a provided in the regions 100b1 and 100b2 is P2.

[0069] FIG. 9B is a schematic cross-sectional view illustrating the arrangement of gas introduction holes 15 according to another embodiment. In FIG. 9(b), in the region 100a, the gas introduction holes 15 are connected to the grooves 14a on the region 100b1 side and the grooves 14a on the region 100b2 side. The pressure of the gas supplied to the grooves 14a provided in the region 100a is P1, and the pressure of the gas supplied to the grooves 14a provided in the regions 100b1 and 100b2 is P2.

[0070] 10(a) and 10(b) are graphs showing the pressure in region 100a, the pressure in regions 100b1 and 100b2, and the pressure at the boundary between region 100a and regions 100b1 and 100b2, obtained by simulation. In the simulation, it is assumed that an object W supported by dots 13 is located above the first main surface 11a of the ceramic dielectric substrate 11. FIG. 10(a) shows the case of FIG. 9(a). FIG. 10(b) shows the case of FIG. 9(b). Furthermore, P1=3×P2, and the dimension of the region 100a in the X direction is set to 50 mm.

[0071] 9(a), on the region 100b2 side of the region 100a, the gas introduction hole 15 is not connected to the groove 14a, and therefore, as can be seen from FIG. 10(a), the region where the gas pressure changes near the boundary becomes larger, and therefore the region where the intended gas pressure is achieved becomes smaller. On the other hand, on the region 100b1 side of the region 100a, the gas introduction hole 15 is connected to the groove 14a, so as can be seen from Figure 10(a), the region where the gas pressure changes near the boundary is small, and therefore the region where the intended gas pressure is achieved can be enlarged. Furthermore, as can be seen from FIG. 10(b), if gas introduction holes 15 are connected to each of the two grooves 14a provided on either side of the boundary, the area where the intended gas pressure is achieved can be further enlarged, which is more preferable.

[0072] As described above, the temperature of the object W can be controlled by the gas pressure. Therefore, if the area where the gas pressure is at the intended level can be increased, the temperature of the object W can be effectively controlled. In addition, the occurrence of in-plane temperature distribution of the object W can be suppressed. As described above, it is preferable that the gas introduction hole 15 is connected to the groove 14a (boundary groove). It is more preferable that the gas introduction hole 15 is connected to each of the two grooves 14a provided on either side of the boundary. In the example shown in FIG. 9(b), two gas introduction holes 15 are provided in the region 100a. For example, both of these two gas introduction holes 15 may be connected to one gas supply path 53 (see FIG. 1).

[0073] Furthermore, when gas introduction holes 15 are connected to each of two grooves 14a provided on either side of a boundary, the angle formed by the line connecting the center of gas introduction hole 15 connected to one groove 14a and the center of gas introduction hole 15 connected to the other groove 14a and the boundary can be less than 90°. In this case, the angle can be, for example, 1.0° to 89°, preferably 2.0° to 70°, and more preferably 3.0° to 60°. In this way, it is possible to place the boundary grooves closer to each other, thereby reducing the area where the gas pressure changes, and therefore increasing the area where the intended gas pressure is achieved.

[0074] The angle formed by the line connecting the center of gas inlet hole 15 connected to one groove 14a and the center of gas inlet hole 15 connected to the other groove 14a and the boundary may be 90°. In this case, the angle need not be 90° in the strict sense, and a difference of the order of, for example, manufacturing error is allowed. In this way, by arranging the two gas introduction holes 15 at opposing positions, the gases with different pressures supplied from the two gas introduction holes 15 compete with each other, making it easier to maintain the pressure in each region at a targeted pressure.

[0075] 11 is a schematic plan view of a ceramic dielectric substrate 11 according to another embodiment of the present invention, which is shown in FIG. 11, a plurality of grooves 14c may be further provided on the first main surface 11a of the ceramic dielectric substrate 11. The width of the grooves 14c (the dimension in a direction substantially perpendicular to the extending direction of the grooves) may be, for example, 0.1 mm or more and 1 mm or less. The depth of the grooves 14c (the dimension in the Z direction) may be, for example, 50 μm or more and 150 μm or less.

[0076] In this example, at least one groove 14c is provided in each of the regions 101, 102, and 104. The groove 14c connects multiple grooves 14a and 14b provided in one region. Therefore, gas supplied to the groove 14a connected to the gas inlet hole 15 flows along the groove 14a and is supplied to the groove 14b and other grooves 14a via the groove 14c. The provision of the groove 14c can smooth the flow of gas, thereby preventing pressure distribution in the region even without a seal ring. Furthermore, even if the tops of the dots 13 wear and the gap between the object W and the first main surface 11a narrows, gas can still be supplied to the groove 14b and other grooves 14a via the groove 14c.

[0077] Groove 14c is arranged so as to communicate with groove 14a and groove 14b. Groove 14c may extend in a direction intersecting grooves 14a and 14b, for example. For example, as shown in FIG. 11 , the plurality of grooves 14c may be arranged on a line passing through the center of the ceramic dielectric substrate 11. The plurality of grooves 14c do not necessarily have to be arranged on a line passing through the center of the ceramic dielectric substrate 11. Although linear grooves 14c are illustrated, the grooves 14c may be curved or may have both linear and curved portions, as long as they can communicate with grooves 14a and 14b. The number, arrangement, shape, etc. of the plurality of grooves 14c may be changed as appropriate depending on the size of the object W, the required specifications for the temperature distribution in the object W, etc. The number, arrangement, shape, etc. of the plurality of grooves 14c may be determined as appropriate, for example, by conducting experiments or simulations.

[0078] In the embodiment of the present invention in which a seal ring is not provided, various measures are taken to improve the responsiveness of the gas pressure within the region. For example, by providing groove 14c that connects groove 14a and groove 14b, the gas pressure within the region can be effectively controlled. Furthermore, because there is a gap between the first main surface 11a and the object W equal to the height of the dots 13, gas supplied to the groove 14a connected to the gas inlet hole 15 is supplied to the groove 14b and other grooves 14a through this gap. However, if the tops of the dots 13 wear and the gap between the object W and the first main surface 11a narrows, the flow of gas within each region may be impeded, potentially resulting in pressure distribution. If the groove 14c is provided, even if the tops of the dots 13 wear and the gap between the object W and the first main surface 11a narrows, gas can still be supplied to the groove 14b and other grooves 14a through the groove 14c. This significantly reduces the time it takes for the pressure within a region to reach a predetermined pressure and suppresses pressure distribution within the region.

[0079] Furthermore, as shown in FIG. 11, at least two gas introduction holes 15 (first gas introduction holes) capable of supplying gas can be provided in a groove 14a (first boundary groove) that is provided in the region 101 (first region) closest to the boundary 102a (first boundary) between the region 101 and the region 102 (second region) and extends along the boundary 102a. In recent years, the density of semiconductor integrated circuits has continued to increase, and plasma density has also increased to achieve even finer processing. If the diameter of gas introduction holes 15 is reduced to suppress arcing under this high-density plasma, there is a risk that individual differences will occur among the individual gas introduction holes 15 due to manufacturing variations, etc. According to this embodiment, the effects of variations in the diameter of each gas introduction hole 15 can be suppressed, and a predetermined flow rate of gas can be more reliably supplied to groove 14a extending along boundary 102a.

[0080] 11, at least two gas introduction holes 15 (second gas introduction holes) capable of supplying gas can be provided in groove 14a (second boundary groove) that is provided in region 102 closest to boundary 102a and extends along boundary 102a. In the example shown in FIG. 11, three gas introduction holes 15 are provided. In this way, similarly to the above, the influence of variations in the hole diameter of each gas introduction hole 15 can be suppressed, and gas can be more reliably supplied to the groove 14a extending along the boundary 102a.

[0081] Next, the effect of the groove 14c will be further described. FIG. 12(a) is a schematic plan view illustrating the arrangement of the grooves 14 according to the comparative example. In Fig. 12(a), a plurality of grooves 14 are provided on the surface of a substrate 110. The plurality of grooves 14 are annular and are provided concentrically at equal intervals around a center 110a of the substrate 110. Note that in Fig. 12(a), groove 14c is not provided. FIG. 12(b) is a schematic plan view illustrating the arrangement of the grooves 14 and 14c. 12(b), there are provided a plurality of grooves 14 and a plurality of grooves 14c that at least partially connect the plurality of grooves 14. In this example, the grooves 14c are provided on a line that passes through the center 110a of the substrate 110. The plurality of grooves 14 are connected to each other via the grooves 14c.

[0082] Fig. 13 is a graph illustrating the pressure change at the center 110a of the substrate 110. Fig. 13 is a graph obtained by simulation of the pressure change at the center 110a of the substrate 110. In the simulation, it is assumed that an object W supported by dots 13 is located above the substrate 110. E in FIG. 13 is the case where a plurality of grooves 14 as illustrated in FIG. 12(a) are provided. F in FIG. 13 is a case where a plurality of grooves 14 and a plurality of grooves 14c are provided as shown in FIG. 12(b).

[0083] As can be seen from Figure 13, in the case of the example shown in Figure 12(a) (case E), the pressure could only be increased to 95% of the specified pressure (20 Torr), which means that a pressure distribution can occur within the region. In the case of the example shown in Figure 12(b) (case F), the pressure could be increased to the specified pressure (20 Torr), which means that the occurrence of pressure distribution within the region can be suppressed. Furthermore, in the case of F, the time T1 required to increase the pressure to the predetermined pressure was shorter than the time T2 required to increase the pressure to 95% of the predetermined pressure in the case of E. This means that the time required for the pressure in the region to reach the predetermined pressure can be significantly reduced, which means that the responsiveness of gas control and therefore temperature control can be improved.

[0084] As described above, it is preferable that the gas introduction hole 15 is connected to at least one of the two grooves 14a provided on either side of the boundary 101a to 103a.

[0085] 11, in inner regions 101, 102, and 104 of first main surface 11a, gas introduction holes 15 can be connected to the outermost grooves 14a provided in each region. In outermost region 103 of first main surface 11a, gas introduction holes 15 can be connected to the innermost grooves 14a.

[0086] The number and arrangement of gas introduction holes 15 provided in each region can be changed as appropriate depending on the size of the target object W, the required specifications for temperature distribution in the target object W, and the like. For example, as illustrated in Fig. 11, three gas introduction holes 15 can be provided at equal intervals in one region. In this case, at least one of the multiple gas introduction holes 15 provided in region 103 and the gas introduction hole 15 provided in region 102 can be arranged on a line passing through the center of the first main surface 11a.

[0087] The above describes a case where the region where gas pressure changes near the boundary is reduced. However, considering the need to supply gas to the grooves 14a and 14c provided in the region, it is preferable to provide the gas inlet 15 at or near the intersection of the grooves 14a and 14c. For example, when projected onto a plane perpendicular to the Z direction, at least a portion of the gas inlet 15 can overlap with at least one of the grooves 14a and 14c at the portion where the grooves 14a and 14c are connected. This facilitates the outflow of gas supplied to the groove 14a toward the groove 14c. This makes it easier to achieve the effects of the groove 14c described above.

[0088] 14(a) to 14(c) are schematic views illustrating the configuration of the grooves 14c. FIG. 14(b) is an enlarged view of part E in FIG. 14(a). FIG. 14(c) is an enlarged view of part F in FIG. 14(a). 14(b), groove 14c can be provided so as to overlap, for example, a line drawn from the center toward the outer periphery of ceramic dielectric substrate 11. In this case, at the portion where groove 14a and groove 14c are connected, the angle formed by the tangent line of groove 14a and groove 14c can be 90°. 14(c), groove 14c may not overlap, for example, a line drawn from the center to the outer periphery of ceramic dielectric substrate 11. In this case, the angle formed by the tangent line of groove 14a and groove 14c at the portion where groove 14a and groove 14c are connected is not 90°.

[0089] FIG. 15 is a schematic plan view of a ceramic dielectric substrate 11 according to another embodiment. In the example shown in FIG. 11, the first main surface 11a is divided into multiple concentric regions 101-104. In contrast, in the example shown in FIG. 15, the first main surface 11a is divided into multiple regions 105 that are in close contact with each other. The multiple regions 105 can be arranged side by side. There are no particular limitations on the outer shape of the multiple regions 105, but it is preferable that the regions 105 have a shape that allows them to be in close contact with each other. The multiple regions 105 can be polygonal, such as a triangle or a rectangle. The outer shape of the region 105 shown in FIG. 15 is a regular hexagon. The outer shape, number, arrangement, etc. of the multiple regions 105 can be changed as appropriate depending on the size of the object W, the required specifications for the temperature distribution in the object W, etc. The outer shape, number, arrangement, etc. of the multiple regions 105 can be determined as appropriate, for example, by conducting experiments or simulations.

[0090] Groove 14a is provided along boundary 105a of region 105. Groove 14a is provided on both sides of boundary 105a. At least one groove 14b is provided in region 105. Groove 14b can be provided concentrically with groove 14a. The number and positions of grooves 14b provided in one region can be changed as appropriate depending on the size of object W, the required specifications for temperature distribution in object W, and the like. The number and positions of grooves 14b provided in one region can be determined as appropriate by, for example, conducting experiments or simulations.

[0091] In addition, similar to those described above, grooves 14c, gas introduction holes 15, dots 13, lift pin holes 16, outer seals 17, etc. may be provided.

[0092] (Processing device) FIG. 16 is a schematic diagram illustrating a processing device 200 according to this embodiment. As shown in FIG. 16, the processing apparatus 200 may include an electrostatic chuck 1, a power supply 210, a medium supply unit 220, and a supply unit 230. The power supply 210 is electrically connected to the electrode 12 provided in the electrostatic chuck 1. The power supply 210 may be, for example, a DC power supply. The power supply 210 applies a predetermined voltage to the electrode 12. The power supply 210 may also be provided with a switch that switches between applying and stopping the voltage application.

[0093] The medium supply unit 220 is connected to the input path 51 and the output path 52. The medium supply unit 220 can supply, for example, a liquid that serves as a cooling medium or a heat-retaining medium. The medium supply unit 220 includes, for example, a storage unit 221 , a control valve 222 , and a discharge unit 223 .

[0094] The storage unit 221 may be, for example, a tank for storing liquid, factory piping, etc. The storage unit 221 may also be provided with a cooling device or a heating device for controlling the temperature of the liquid. The storage unit 221 may also be provided with a pump for pumping the liquid.

[0095] The control valve 222 is connected between the input path 51 and the storage portion 221. The control valve 222 can control at least one of the flow rate and pressure of the liquid. The control valve 222 can also switch between supplying and stopping the supply of the liquid.

[0096] The discharge part 223 is connected to the output path 52. The discharge part 223 can be a tank or a drain pipe that collects the liquid discharged from the output path 52. Note that the discharge part 223 is not necessarily required, and the liquid discharged from the output path 52 may be supplied to the storage part 221. In this way, the cooling medium or heat-retaining medium can be circulated, thereby saving resources.

[0097] The supply unit 230 includes a gas supply unit 231 and a gas control unit 232 . The gas supply unit 231 may be a high-pressure cylinder containing a gas such as helium, factory piping, etc. Although the example has been given in which one gas supply unit 231 is provided, a plurality of gas supply units 231 may be provided.

[0098] The gas control unit 232 is connected between the gas supply lines 53 and the gas supply unit 231. The gas control unit 232 can control at least one of the flow rate and pressure of the gas. The gas control unit 232 can also have a function of switching between supplying and stopping the gas supply. The gas control unit 232 can be, for example, a mass flow controller or a mass flow meter.

[0099] 16, a plurality of gas control units 232 can be provided. For example, a gas control unit 232 can be provided for each of the plurality of regions 101 to 104. In this way, the gas to be supplied can be controlled for each of the plurality of regions 101 to 104. In this case, a gas control unit 232 can also be provided for each of the plurality of gas supply paths 53. In this way, gas control in the plurality of regions 101 to 104 can be performed more precisely. Although the case where a plurality of gas control units 232 are provided has been exemplified, a single gas control unit 232 may be provided as long as it can independently control the supply of gas in the plurality of supply systems.

[0100] Here, means for holding the object W include a vacuum chuck and a mechanical chuck. However, a vacuum chuck cannot be used in an environment where the pressure is reduced below atmospheric pressure. Furthermore, the use of a mechanical chuck may damage the object W or generate particles. For this reason, electrostatic chucks are used in processing equipment used in, for example, semiconductor manufacturing processes.

[0101] In such a processing apparatus, the processing space needs to be isolated from the external environment. Therefore, the processing apparatus 200 may further include a chamber 240. The chamber 240 may have, for example, an airtight structure capable of maintaining an atmosphere at a pressure lower than atmospheric pressure. The processing device 200 may also include a plurality of lift pins and a drive device for raising and lowering the plurality of lift pins. When receiving the object W from the transport device or transferring the object W to the transport device, the lift 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 on the first main surface 11a, the lift pins are lowered by the drive device and stored inside the ceramic dielectric substrate 11.

[0102] Furthermore, the processing apparatus 200 may be provided with various devices depending on the type of processing. For example, a vacuum pump for evacuating the interior of the chamber 240 may be provided. A plasma generating device for generating plasma may be provided inside the chamber 240. A process gas supply unit for supplying process gas into the chamber 240 may be provided. A heater for heating the object W and process gas inside the chamber 240 may also be provided. Note that the devices provided in the processing apparatus 200 are not limited to those exemplified. Known technologies can be applied to the devices provided in the processing apparatus 200, so detailed description will be omitted.

[0103] As described above, the processing apparatus 200 according to this embodiment includes the electrostatic chuck 1 described above and a gas control unit (gas control unit 232) capable of independently controlling the gas supplied to the first gas introduction hole (gas introduction hole 15) and the second gas introduction hole (gas introduction hole 15) provided in the electrostatic chuck 1. The processing apparatus 200 according to this embodiment can adjust the gas pressure in each region to an appropriate level.

[0104] The above describes embodiments of the present invention. However, the present invention is not limited to these descriptions. For example, while the electrostatic chuck 1 uses Coulomb force, it may use Johnsen-Rahbek force. Furthermore, even if a person skilled in the art appropriately modifies the design of the above-described embodiments, the modifications are within the scope of the present invention as long as they incorporate the features of the present invention. Furthermore, the elements of the above-described embodiments can be combined to the extent technically possible, and such combinations are also within the scope of the present invention as long as they incorporate the features of the present invention. [Explanation of symbols]

[0105] 1 electrostatic chuck, 11 ceramic dielectric substrate, 11a first main surface, 11b second main surface, 12 electrode, 13 dot, 14a to 14c groove, 15 gas inlet hole, 16 lift pin hole, 17 outer seal, 50 base plate, 51 input path, 52 output path, 53 gas supply path, 70 second porous portion, 90 first porous portion, 101 to 104 regions, 101a to 103a boundaries, 200 processing device, 231 gas supply unit, 232 gas control unit, W object

Claims

1. A base plate and a ceramic dielectric substrate provided on the base plate, the ceramic dielectric substrate having a first main surface exposed to the outside and a plurality of dots provided on the first main surface; Equipped with the first main surface includes at least a first region and a second region adjacent to the first region, a plurality of first grooves and at least one first gas introduction hole connected to at least one of the plurality of first grooves are provided in the first region of the first main surface; the plurality of first grooves include a first boundary groove provided closest to a first boundary between the first region and the second region and extending along the first boundary; a plurality of second grooves and at least one second gas introduction hole connected to at least one of the plurality of second grooves are provided in the second region of the first main surface; the plurality of second grooves include a second boundary groove provided closest to the first boundary and extending along the first boundary; an object is placed on the plurality of dots, whereby the object is supported by the dots, and a space is formed between the object and the first main surface; a gas supplied to one of the first boundary groove and the second boundary groove is supplied to the other through the space; An electrostatic chuck, wherein a distance between groove ends of the first boundary groove and the second boundary groove is greater than 0 mm and is not greater than 60 mm.

2. 2. The electrostatic chuck according to claim 1, wherein a distance between the groove ends of the first boundary groove and the second boundary groove is greater than 0 mm and equal to or less than 20 mm.

3. 3. The electrostatic chuck according to claim 1, wherein at least a portion of the first gas introduction hole overlaps with the first boundary groove when projected onto a plane perpendicular to a first direction extending from the base plate toward the ceramic dielectric substrate.

4. 4. The electrostatic chuck according to claim 1, wherein at least a portion of the second gas introduction hole overlaps with the second boundary groove when projected onto a plane perpendicular to a first direction extending from the base plate toward the ceramic dielectric substrate.

5. 5. The electrostatic chuck according to claim 1, wherein an angle formed between a line connecting a center of the first gas introduction hole and a center of the second gas introduction hole and the first boundary is less than 90°.

6. 5. The electrostatic chuck according to claim 1, wherein an angle formed between a line connecting a center of the first gas introduction hole and a center of the second gas introduction hole and the first boundary is 90 degrees.

7. The plurality of first grooves include at least one first region groove different from the first boundary groove; a lift pin hole provided in the first main surface, 7. The electrostatic chuck according to claim 1, wherein a distance between the lift pin hole and the first boundary groove is greater than a distance between the lift pin hole and the first region inner groove closest to the lift pin hole.

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