Electrostatic chuck

Abstract

The present invention provides an electrostatic chuck, specifically comprising: a base plate; and a ceramic dielectric substrate having a first main surface, wherein the first main surface includes at least a first region and a second region adjacent to the first region, wherein the first region is provided with a plurality of first grooves, at least one first gas introduction hole connected to at least one of the plurality of first grooves, and at least one second groove extending in a direction intersecting the plurality of first grooves, wherein each of the plurality of first grooves has a substantially circular planar shape and is concentrically arranged, wherein the second groove is connected to at least two of the first grooves, and when projected onto a plane perpendicular to a first direction from the base plate toward the ceramic dielectric substrate, at least a portion of the first gas introduction hole overlaps with at least one of the first groove and the second groove in a portion connecting the first groove and the second groove.

Description

Technical Field

[0001] An aspect of the present invention relates to an electrostatic chuck. Background Art

[0002] The electrostatic chuck has, for example, a ceramic dielectric substrate made of alumina or the like, and electrodes disposed inside the ceramic dielectric substrate. When electricity is applied to the electrodes, electrostatic force is generated. The electrostatic chuck is a device that uses the generated electrostatic force to adsorb an object such as a silicon wafer. In such an electrostatic chuck, an inert gas such as helium (He) (hereinafter simply referred to as gas) flows between the surface of the ceramic dielectric substrate and the back of the object in order to control the temperature of the object.

[0003] For example, in devices that process substrates, such as CVD (Chemical Vapor Deposition) devices, sputtering devices, ion implantation devices, and etching devices, the temperature of the substrate may rise during the process. Therefore, in an electrostatic chuck used in such a device, a gas is flowed between a ceramic dielectric substrate and the substrate so that the gas contacts the substrate, thereby achieving heat dissipation from the substrate.

[0004] For example, there has been proposed a technique of providing concentric circular grooves and radial grooves on the surface of a ceramic dielectric substrate, or connecting holes for supplying gas to the radial grooves (for example, see Patent Document 1).

[0005] In addition, during the treatment, a temperature distribution is generated in the surface of the object. At this time, if the gas pressure increases, the heat release from the object increases, so the temperature of the object can be reduced. Therefore, the surface of the ceramic dielectric substrate on the object side can be divided into multiple regions, and the gas pressure in the multiple regions can be changed to control the temperature in the surface of the object.

[0006] For example, in order to control the gas pressure in each area, a technique of providing a seal ring between each area has been proposed (see, for example, Patent Document 2).

[0007] At this time, in order to control the gas pressure in each area, it is preferred to use a sealing ring to airtightly separate each area. However, in this way, particles generated during the wafer processing process become easy to accumulate on the sealing ring part, which may cause inconveniences such as defects in this part.

[0008] There is also proposed a technique in which a minute gap is provided between the top of a seal ring and an object to control the gas pressure in each region (see Patent Document 3).

[0009] In this case as well, the problem that particles are easily accumulated on the seal ring portion cannot be solved.

[0010] Therefore, it is desired to develop a technology capable of suppressing the accumulation of particles on the seal ring portion while effectively controlling the gas pressure in each region.

[0011] Patent Literature

[0012] Patent Document 1: Japanese Patent No. 5462946

[0013] Patent Document 2: Japanese Patent Application Publication No. 2011-119708

[0014] Patent Document 3: Japanese Patent Application Publication No. 2012-129547 Summary of the invention

[0015] The present invention has been made based on the recognition of such a problem, and the technical problem to be solved is to provide an electrostatic chuck that can effectively control the gas pressure in each area while suppressing the accumulation of particles on the seal ring portion.

[0016] The first invention is an electrostatic chuck comprising: a base plate; and a ceramic dielectric substrate, which is provided on the base plate, has a substantially circular planar shape, and has a first main surface exposed to the outside, wherein the first main surface includes at least a first region (region 101) and a second region (region 102) adjacent to the first region, wherein the first region is provided with a plurality of first grooves (grooves 14a, 14b), at least one first gas introduction hole (gas introduction hole 15) connected to at least one of the plurality of first grooves, and at least one second groove (groove 14c) extending in a direction intersecting the plurality of first grooves, wherein each of the plurality of first grooves has a substantially circular planar shape and is provided concentrically, wherein the second groove is connected to at least two of the first grooves, and when projected onto a plane perpendicular to a first direction from the base plate toward the ceramic dielectric substrate, at a portion connecting the first groove and the second groove, at least a portion of the first gas introduction hole overlaps with at least one of the first groove and the second groove.

[0017] The electrostatic chuck does not have a sealing ring disposed between the regions in order to control the gas pressure in each region as in the past. That is, when an object W is provided, a closed space is formed by the object W and the ceramic dielectric substrate (the first region and the second region). Therefore, the problem of particles accumulating on the sealing ring portion can be solved. On the other hand, if the sealing ring is simply not provided, it is difficult to achieve the division of the gas pressure of each region, which will result in reduced gas pressure controllability. Therefore, in the present invention, not only the sealing ring is eliminated, but also the distance between the groove ends between the first boundary groove and the second boundary groove is studied so as to make it smaller than the distance between the groove ends between the first boundary groove and the groove in the first region adjacent to the first boundary groove.

[0018] In addition, according to the electrostatic chuck, the area where the gas pressure changes near the boundary between the areas can be reduced, and the area where the desired gas pressure is achieved can be increased. Therefore, the gas pressure in each area can be effectively controlled while solving the problem of particle accumulation.

[0019] A second invention is an electrostatic chuck according to the first invention, characterized in that at least two second grooves are provided in the first region.

[0020] According to this electrostatic chuck, the pressure at the first boundary between the first region and the second region can be made close to the average value of the pressure in the first region and the pressure in the second region. Therefore, it is easier to maintain the pressure in each region at the target pressure.

[0021] The third invention is an electrostatic suction cup, characterized in that, in the first invention, in the second area, there are also provided: a plurality of third grooves (grooves 14a, 14b); at least one second gas inlet hole (gas inlet hole 15), connected to at least one of the plurality of third grooves; and at least one fourth groove (groove 14c), extending in a direction intersecting the plurality of third grooves, connected to at least two of the third grooves, wherein the planar shape of each of the plurality of third grooves is roughly circular, and they are concentrically arranged with the center of the plurality of first grooves as the center, and when projected onto a plane perpendicular to the first direction, at least a portion of the second gas inlet hole overlaps with at least any one of the third groove and the fourth groove on the portion connecting the third groove and the fourth groove.

[0022] According to the electrostatic chuck, it is possible to suppress the pressure distribution in the first region and the second region. In addition, it is possible to significantly shorten the time until the pressure in the first region and the pressure in the second region reach a predetermined pressure, in other words, it is possible to improve the responsiveness of gas control and temperature control.

[0023] A fourth invention is an electrostatic chuck according to the third invention, characterized in that at least two fourth grooves are provided in the second region.

[0024] According to this electrostatic chuck, the pressure at the first boundary between the first region and the second region can be made close to the average value of the pressure in the first region and the pressure in the second region. Therefore, it is easier to maintain the pressure in each region at the target pressure.

[0025] The fifth invention is an electrostatic suction cup, characterized in that, in the third invention, the second region is arranged outside the first region relative to the center of the first main surface, and when projected onto a plane perpendicular to the first direction, in the first region, on a portion connecting the first groove and the second groove located on the outermost side, at least a portion of the first gas inlet hole overlaps with at least any one of the first groove and the second groove located on the outermost side, and in the second region, on a portion connecting the third groove and the fourth groove located on the innermost side, at least a portion of the second gas inlet hole overlaps with at least any one of the third groove and the fourth groove located on the innermost side.

[0026] According to this electrostatic chuck, the gas supplied from the first gas introduction hole can be easily made to flow to at least one of the first groove and the second groove. Therefore, the above-mentioned effect can be easily obtained.

[0027] The sixth invention is an electrostatic chuck characterized in that, in the third invention, the angle formed by a line connecting the center of the first gas inlet hole and the center of the second gas inlet hole and the first boundary between the first area and the second area is less than 90°.

[0028] According to this electrostatic chuck, the boundary grooves can be brought closer together, thereby reducing the area where the gas pressure changes. Therefore, the area where the desired gas pressure is achieved can be increased.

[0029] The seventh invention is an electrostatic chuck characterized in that, in the third invention, the angle formed by a line connecting the center of the first gas inlet hole and the center of the second gas inlet hole and the first boundary between the first area and the second area is 90°.

[0030] According to this electrostatic chuck, it is easier to maintain the pressure in each region at the target pressure.

[0031] The eighth invention is an electrostatic suction cup, characterized in that, in the seventh invention, there is also a lifting pin hole arranged in the first area, and the distance between the lifting pin hole and the first groove located at the outermost side is larger than the distance between the lifting pin hole and the first groove among the multiple first grooves except the first groove located at the outermost side and closest to the lifting pin hole.

[0032] According to this electrostatic chuck, pressure changes in the region can be reduced.

[0033] According to aspects of the present invention, it is possible to provide an electrostatic chuck capable of effectively controlling the gas pressure in each region and suppressing the accumulation of particles on the seal ring portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1It is a schematic cross-sectional view for illustrating the electrostatic chuck according to the present embodiment.

[0035] Figure 2 It is a schematic cross-sectional view for illustrating a ceramic dielectric substrate, an electrode, and a first porous portion.

[0036] Figure 3 (a) is a schematic cross-sectional view for illustrating the arrangement of grooves and the arrangement of gas introduction holes according to a comparative example. Figure 3 (b) is a schematic cross-sectional view for illustrating an example of the arrangement of the grooves and the arrangement of the gas introduction holes according to the present embodiment.

[0037] Figure 4 This is a graph showing the pressure of a region and the pressure of a boundary between regions obtained by simulation.

[0038] Figure 5 is a graph used to illustrate the effect of boundary groove spacing.

[0039] Figure 6 (a) is a graph for illustrating the effect of the boundary groove interval through the “gradient deviation rate”. Figure 6 (b) is a graph for explaining the "gradient deviation rate".

[0040] Figure 7 yes Figure 6 Enlarged view of section H in (a).

[0041] Figure 8 This is a graph for illustrating the effect of the number of second grooves (grooves 14a and 14b).

[0042] Fig. 9 (a) is a schematic cross-sectional view for illustrating the arrangement of the gas introduction holes. Fig. 9 (b) is a schematic cross-sectional view for illustrating the arrangement of gas introduction holes according to another embodiment.

[0043] Fig.10 (a) Fig.10 (b) is a graph showing the pressure of a region and the pressure of a boundary between regions obtained by simulation.

[0044] Fig.11 It is a schematic plan view of a ceramic dielectric substrate according to another embodiment.

[0045] Fig.12 (a) is a schematic plan view for illustrating the arrangement of grooves according to a comparative example. Fig.12 (b) is a schematic top view for illustrating the arrangement of the grooves.

[0046] Fig.13is a graph for illustrating pressure changes on the center of the substrate.

[0047] Fig.14 (a)~ Fig.14 (c) is a schematic diagram for illustrating the form of the groove 14c.

[0048] Fig.15 It is a schematic plan view of a ceramic dielectric substrate according to another embodiment.

[0049] Fig.16 This is a schematic diagram for illustrating a processing device according to this embodiment.

[0050] Explanation of symbols

[0051] 1-electrostatic suction cup; 11-ceramic dielectric substrate; 11a-first main surface; 11b-second main surface; 12-electrode; 13-dot; 14a~14c-grooves; 15-gas inlet hole; 16-lifting pin hole; 17-external seal; 50-base plate; 51-input path; 52-output path; 53-gas supply path; 70-second porous part; 90-first porous part; 101~104-area; 101a~103a-boundary; 200-processing device; 231-gas supply part; 232-gas control part; W-object. DETAILED DESCRIPTION

[0052] Hereinafter, the embodiment of the present invention will be described with reference to the accompanying drawings. In addition, in each of the drawings, the same components are marked with the same reference numerals, and detailed descriptions thereof are appropriately omitted.

[0053] In each figure, the direction from the base plate 50 toward the ceramic dielectric substrate 11 is referred to as the Z direction, one direction substantially perpendicular to the Z direction is referred to as the Y direction, and the direction substantially perpendicular to the Z direction and the Y direction is referred to as the X direction.

[0054] (Electrostatic chuck)

[0055] Figure 1 It is a schematic cross-sectional view for illustrating the electrostatic chuck 1 according to the present embodiment.

[0056] Figure 2 It is a schematic cross-sectional view illustrating the ceramic dielectric substrate 11 , the electrode 12 , and the first porous portion 90 .

[0057] like Figure 1 As shown, on the electrostatic chuck 1, a ceramic dielectric substrate 11, an electrode 12, a first porous portion 90, a base plate 50, and a second porous portion 70 may be provided.

[0058] like Figure 1 and Figure 2As shown, the ceramic dielectric substrate 11 may be, for example, a flat plate-shaped component using sintered ceramic. For example, the ceramic dielectric substrate 11 may contain aluminum oxide (Al2O3). For example, the ceramic dielectric substrate 11 may be formed using high-purity aluminum oxide. The concentration of aluminum oxide in the ceramic dielectric substrate 11 may be, for example, 99 atomic percent (atοmic %) or more and 100 atomic % or less. If high-purity aluminum oxide is used, the plasma resistance of the ceramic dielectric substrate 11 can be improved. The porosity of the ceramic dielectric substrate 11 may be, for example, less than 1%. The density of the ceramic dielectric substrate 11 may be, for example, 4.2 g / cm 3 .

[0059] The ceramic dielectric substrate 11 has a first main surface 11a on which the attracted object W is placed and a second main surface 11b opposite to the first main surface 11a. The first main surface 11a is a surface exposed to the outside of the electrostatic chuck 1. The object W may be, for example, a semiconductor substrate such as a silicon wafer or a glass substrate.

[0060] 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 supported by the plurality of dots 13. If a plurality of dots 13 are provided, a space is formed between the back side 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, for example, the particles attached to the object W can be made into a preferred state. For example, the height (dimension in the Z direction) of the plurality of dots 13 can be greater than 1 μm and less than 100 μm, preferably greater than 1 μm and less than 30 μm, and more preferably greater than 5 μm and less than 15 μm.

[0061] 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 on the first main surface 11a side of the ceramic dielectric substrate 11. The width (dimension in the X direction or the Y direction) of the groove 14a 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. The depth (dimension in the Z direction) of the groove 14a can be, for example, 10 μm or more and 300 μm or less, preferably 10 μm or more and 200 μm or less, and more preferably 50 μm or more and 150 μm or less. The width (dimension in the X direction or the Y direction) of the groove 14b can be, for example, 0.1 mm or more and 1.0 mm or less. 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.

[0062] A plurality of gas introduction holes 15 are provided on the ceramic dielectric substrate 11. 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 the gas supply path 53 described later via the 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, and penetrate the ceramic dielectric substrate 11. The diameter of the gas introduction holes 15 can be, for example, not less than 0.05 mm and not more than 0.5 mm.

[0063] Note that the details of the plurality of grooves 14 a and 14 b and the plurality of gas introduction holes 15 will be described later.

[0064] 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.

[0065] The shape of the electrode 12 may be, for example, 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 adsorption electrode for adsorbing and holding the object W. The electrode 12 may be a monopolar type or a bipolar type. Figure 1 The illustrated electrode 12 is a bipolar type, and two electrodes 12 are provided on the same surface.

[0066] The electrode 12 is provided with a connection portion 20. The electrode 12 and the connection portion 20 may be formed of a conductive material such as a metal. The end of the connection portion 20 on the opposite side to the electrode 12 side may be exposed on the second main surface 11b side of the ceramic dielectric substrate 11. The connection portion 20 may be, for example, a via (solid type) or a via hole (hollow type) that is conductive with the electrode 12. The connection portion 20 may also be a metal terminal connected by an appropriate method such as soldering.

[0067] The power source 210 is electrically connected to the electrode 12 via the connection portion 20. When a predetermined voltage is applied to the electrode 12, electric charges are generated in the region on the first main surface 11a side of the electrode 12. Therefore, the object W is attracted and held on the first main surface 11a side of the ceramic dielectric substrate 11 by electrostatic force.

[0068] The first porous portion 90 is provided inside the ceramic dielectric substrate 11. The first porous portion 90 may be provided, for example, between the base plate 50 and the first main surface 11a of the ceramic dielectric substrate 11 in the Z direction and at a position facing the gas supply path 53. For example, the first porous portion 90 may 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.

[0069] exist Figure 1 and Figure 2 In the case of the first porous portion 90 illustrated, the first porous portion 90 is provided on the portion on the second main surface 11b side of the gas introduction hole 15. One end of the first porous portion 90 is exposed on 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. In addition, the other end of the first porous portion 90 may be exposed on the bottom surface of the groove 14a. In addition, both ends of the first porous portion 90 may be located between the first main surface 11a and the second main surface 11b.

[0070] The material of the first porous portion 90 may be, for example, ceramics having insulation properties. The first porous portion 90 may include, for example, at least one of aluminum oxide (Al2O3), titanium oxide (TiO2), and yttrium oxide (Y2O3). In this way, the first porous portion 90 having high insulation withstand voltage and high rigidity may be formed.

[0071] In this case, the purity of aluminum oxide of the ceramic dielectric substrate 11 can be made higher than the purity of aluminum oxide of the first porous portion 90. In this way, the performance of the electrostatic chuck 1 such as plasma resistance can be ensured, and the mechanical strength of the first porous portion 90 can be ensured. As an example, by making the first porous portion 90 contain a trace amount of additives, the sintering of the first porous portion 90 can be promoted, and the control of pores and the mechanical strength can be ensured.

[0072] For example, the purity of ceramics such as alumina can be measured by fluorescent X-ray analysis, ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry), or the like.

[0073] like Figure 1 As shown, the base plate 50 supports, for example, a ceramic dielectric substrate 11. The ceramic dielectric substrate 11 may be bonded to the base plate 50, for example. The adhesive may be, for example, a silicone adhesive.

[0074] The base plate 50 is made of metal, for example. The base plate 50 is divided into an upper portion 50a and a lower portion 50b, for example, made of 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.

[0075] The base plate 50 also plays a role in adjusting the temperature of the dielectric substrate 11. For example, when cooling the dielectric substrate 11, a cooling medium flows in from the input path 51, passes through the connection path 55, and flows out from the output path 52. In this way, the cooling medium can absorb the heat of the base plate 50 and cool the ceramic dielectric substrate 11 mounted thereon. In addition, when keeping the dielectric substrate 11 warm, the heat-keeping medium can be flowed into the connection path 55. If the temperature of the dielectric substrate 11 can be controlled, it is easy to control the temperature of the object W adsorbed and held on the dielectric substrate 11.

[0076] Gas is supplied to the plurality of grooves 14a and 14b. By bringing the supplied gas into contact with the object W, the temperature of the object W can be controlled. At this time, if the temperature of the base plate 50 can be controlled, the range of temperature control of the gas supplied to the grooves 14a and 14b can be reduced. 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 and 14b.

[0077] A plurality of gas supply paths 53 may be provided on the base plate 50. The gas supply paths 53 may be provided so as to penetrate the base plate 50. The gas supply paths 53 may also be branched from other gas supply paths 53 midway and provided to the ceramic dielectric substrate 11 side without penetrating the base plate 50.

[0078] The gas supply path 53 is connected to the gas introduction hole 15. That is, the gas flowing into the gas supply path 53 flows into the gas introduction hole 15 after passing through the gas supply path 53.

[0079] The gas flowing into the gas introduction hole 15 flows into the groove 14a connected to the gas introduction hole 15 after passing through the gas introduction hole 15. Thus, the object W can be directly cooled by the gas.

[0080] The second porous portion 70 may 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 embedded in the end surface of the base plate 50 on the ceramic dielectric substrate 11 side. Figure 1 As shown, for example, a countersunk portion 53a is provided on the end surface of the base plate 50 on the ceramic dielectric substrate 11 side, and the second porous portion 70 can be fitted into the countersunk portion 53a. The countersunk portion 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.

[0081] Next, the plurality of grooves 14 a and 14 b and the plurality of gas introduction holes 15 will be further described.

[0082] As described above, the temperature of the object W can be controlled by the gas supplied to the plurality of grooves 14a and 14b. In the process of the object W, there is a case where a temperature distribution is generated in the surface of the object W. For example, there is a case where a low temperature area and a high temperature area are generated in the surface of the object W. In this case, if the pressure of the gas in contact with the high temperature area is made higher than the pressure of the gas in contact with the low temperature area, the heat release from the high temperature area can be increased, so it is possible to control the temperature of the object W while suppressing the generation of a temperature distribution in the surface of the object W.

[0083] For example, by dividing the first main surface 11a side of the ceramic dielectric substrate 11 into a plurality of regions and changing the gas pressure supplied to the plurality of regions, the in-plane temperature of the object W can be controlled. At this time, in order to control the gas pressure in each region, there is a case where a sealing ring is provided between the regions so as to separate the regions. In this example, the top of the sealing ring is brought into contact with the surface on the first main surface 11a side of the object W. In this way, since the flow of gas between the regions can be substantially eliminated, the gas pressure in each region can be effectively controlled.

[0084] However, when a seal ring is provided, particles generated during the wafer processing process are likely to accumulate on the seal ring portion, which may cause problems such as defects in the portion.

[0085] Therefore, in the present invention, a seal ring for separating the regions is not provided, but the arrangement of the grooves 14a and 14b is studied. That is, when the object W is provided, a closed space is formed by the object W and the ceramic dielectric substrate 11 (for example, the region 101 and the region 102). According to the present invention, pressure control within the region can be effectively performed even without a seal ring.

[0086] In addition, in the present invention, a sealing ring is not substantially provided, and it is sufficient as long as the gas pressure in each area can be effectively controlled, and it does not prevent the sealing ring from being partially or locally provided. In other words, as long as the effect of effectively controlling the gas pressure in each area can be obtained without substantially providing a sealing ring, a sealing ring may be partially or locally provided.

[0087] Figure 3 (a) is a schematic cross-sectional view for illustrating the arrangement of the grooves 14 and the arrangement of the gas introduction holes 15 according to the comparative example.

[0088] exist Figure 3 In (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 made constant.

[0089] In addition, in this specification, the distance between the groove ends means the shortest distance between the inner wall on the other groove side of one groove and the inner wall on one groove side of the other groove when there are two adjacent grooves. In this case, when the distance between the groove ends of the two grooves changes, the shortest distance can be used as the distance between the groove ends.

[0090] In addition, in the X direction, region 100a is adjacent to region 100b1 and region 100a is adjacent to region 100b2. In Figure 3 In the configuration illustrated in (a), gas introduction holes 15 are connected to two grooves 14 provided across the boundary between region 100a and region 100b1.

[0091] In addition, the gas pressure supplied to the groove 14 provided in region 100a is denoted as P1, the gas pressure supplied to the groove 14 provided in region 100b1 is denoted as P2, and the gas pressure supplied to the groove 14 provided in region 100b2 is denoted as P3.

[0092] Figure 3 (b) is a schematic cross-sectional view for exemplifying an example of the arrangement of grooves 14a and 14b and the arrangement of gas introduction holes 15 according to the present embodiment. Groove 14a is a boundary groove provided across the boundary between different regions, and groove 14b is an in-region groove provided within the region other than groove 14a.

[0093] In Figure 3 (b), the distance between the groove ends (boundary groove interval) of two grooves 14a (boundary grooves) provided across the boundary between region 100a and regions 100b1 and 100b2 in the X direction is denoted as L21, and the distance between the groove ends (in-region groove interval) between groove 14a (boundary groove) and a groove 14b (in-region groove) other than groove 14a provided within region 100a adjacent to this boundary groove 14a is denoted as L22. At this time, L21 < L22. In addition, the distances between the groove ends between groove 14a (boundary groove) and grooves 14b other than groove 14a provided within regions 100b1 and 100b2 adjacent to this boundary groove 14a are denoted as L24, respectively.

[0094] In addition, the gas pressure supplied to groove 14a provided in region 100a via gas introduction hole 15 is denoted as P1, and the gas pressure supplied to groove 14a provided in region 100b1 is denoted as P2.

[0095] Figure 4 is a pressure curve graph of the pressure in region 100a, the pressures 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, an object W supported by dots 13 is simulated above the first main surface 11a of the ceramic dielectric substrate 11.

[0096] Figure 4 A in is, Figure 3 (a) is an example in which the arrangement of the grooves 14, the arrangement of the gas introduction holes 15, and the boundary groove interval are equal to the groove interval within the region.

[0097] Figure 4 In B, Figure 3 (b) The example in which the arrangement of the grooves 14a and 14b, the arrangement of the gas introduction holes 15, and the interval between the boundary grooves are smaller than the interval between the grooves within the region. In any of the examples, no seal ring is provided between the regions.

[0098] In the simulation, P1=3×P2 was set, and the distance L21 between the groove ends was set to 5 mm, the distance L22 between the groove ends was set to 20 mm, and the distance L23 between the groove ends was set to 15 mm. The size of the region 100 a in the X direction was set to 50 mm.

[0099] Depend on Figure 4 It can be seen that when the boundary groove interval is equal to the intra-region groove interval (case A), the area where the gas pressure changes near the boundary between the region 100a and the regions 100b1 and 100b2 becomes larger. On the contrary, when the boundary groove interval is smaller than the intra-region groove interval (case B), the area where the gas pressure changes near the boundary between the region 100a and the regions 100b1 and 100b2 can be made smaller than that in case A. That is, in any of the regions 100a, 100b1, and 100b2, the area where the desired gas pressure is achieved can be increased, thereby improving the uniformity of the gas pressure within the region.

[0100] As described above, by studying the arrangement of the grooves 14a and 14b, even when a seal ring is not provided between the regions, the temperature of the object W can be controlled by using the gas pressure. Therefore, if the uniformity of the gas pressure in the region can be improved, the temperature of the object W in the portion corresponding to the region can be more effectively controlled. In addition, the occurrence of in-plane distribution in the temperature of the object W can be suppressed.

[0101] Furthermore, according to the findings obtained by the inventors, it is preferable to connect the gas introduction hole 15 to at least one of the two grooves 14 a which are boundary grooves provided sandwiching the boundary, because the above-mentioned effects can be obtained.

[0102] At this time, since there is a gap of only the height of the dot 13 between the first main surface 11a and the object W, the gas supplied to the groove 14a connected to the gas introduction hole 15 is supplied to the groove 14b and other grooves 14a through the gap. That is, in each area, 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.

[0103] In addition, like Figure 3 As shown in (b), when the two grooves 14a provided sandwiching the boundary are connected to the gas introduction holes 15 respectively, the change of the gas pressure at the boundary of the region can be made more significant, and the temperature of the object W can be more effectively controlled, which is more preferable. In addition, the occurrence of in-plane distribution in the temperature of the object W can be more effectively suppressed.

[0104] Figure 5 is a graph used to illustrate the effect of boundary groove spacing.

[0105] The boundary groove interval on the horizontal axis is the distance between the groove ends of two grooves (boundary grooves) provided to sandwich the boundary of adjacent regions. The effect of the boundary groove interval is the effect of the boundary groove interval itself, and can be applied, for example Figure 3 (a) The distance L23 shown in the example can also be applied Figure 3 (b) Illustrated distance L21.

[0106] The deviation rate on the vertical axis indicates how much the average pressure in each region deviates from the set pressure (expected pressure). If the deviation rate increases, it means that the difference between the average pressure in each region and the expected pressure increases.

[0107] Figure 5 For example, Figure 3 (a) Figure 3 In (b), the pressure P1 of the region 100a is 20 Torr (2666.4 Pa), and the pressure P3 of the region 100b2 is 60 Torr (7999.2 Pa), and the deviation rate is obtained by simulation.

[0108] Depend on Figure 5 It can be seen that if the distance between the groove ends of the boundary grooves, i.e., the boundary groove interval, exceeds 0 mm and is less than 60 mm, preferably exceeds 0 mm and is less than 20 mm, the deviation rate increases approximately linearly. If the boundary groove interval exceeds 60 mm, the deviation rate increases exponentially. This means that if the boundary groove interval is less than 60 mm, preferably less than 20 mm, the increase in the deviation rate can be suppressed, and the average pressure in each area is close to the expected pressure.

[0109] As mentioned above, since the effect of the boundary groove spacing is the effect of the boundary groove spacing itself, if the configuration of the aforementioned grooves 14a, 14b, the configuration of the aforementioned gas inlet hole 15 (the gas inlet hole 15 is connected to the boundary groove), and the groove 14c described later are appropriately combined, the gas pressure in each area can be further effectively controlled while effectively suppressing the accumulation of particles on the sealing ring part.

[0110] Figure 6 (a) is a graph for illustrating the effect of the boundary groove interval through the “gradient deviation rate”.

[0111] Figure 6 (b) is a graph for explaining the "gradient deviation rate".

[0112] Figure 7 yes Figure 6 Enlarged view of section H in (a).

[0113] If the pressure in the first region and the pressure in the second region are ideally divided, then Figure 6 As shown in (b), the pressure distribution on the first boundary between the first region and the second region is considered to be a linear distribution (linear change). Therefore, if the gradient is arithmetically calculated from the pressure distribution, which is the pressure distribution between regions obtained by analysis, and the deviation rate from the ideal gradient (gradient deviation rate) is obtained, the effect of the boundary groove spacing can be evaluated.

[0114] Depend on Figure 6 (a) It can be seen that if the distance between the groove ends of the boundary grooves, i.e., the boundary groove interval, exceeds 0 mm and is less than 60 mm, the gradient deviation rate increases approximately linearly. If the boundary groove interval exceeds 60 mm, the gradient deviation rate increases exponentially. This means that if the boundary groove interval is less than 60 mm, the increase in the gradient deviation rate can be suppressed, and the average pressure in each area is close to the expected pressure.

[0115] In addition, further Figure 7 It can be seen that if the distance between the groove ends of the boundary grooves, i.e., the boundary groove interval, exceeds 0 mm and is less than 20 mm, the gradient deviation rate can be made closer to linearity. This means that if the boundary groove interval is less than 20 mm, the increase in the gradient deviation rate can be further suppressed, and the average pressure in each area is closer to the expected pressure.

[0116] Figure 8 This is a graph for illustrating the effect of the number of second grooves (radial grooves 14a and 14b).

[0117] Depend on Figure 8It can be seen that if at least two second grooves are provided in the second region, the deviation rate can be made very small. 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 close to the average value of the pressure in the first region and the pressure in the second region. Therefore, it is easier to maintain the pressure in each region at the target pressure.

[0118] According to the findings obtained by the inventors, if the boundary slot occupancy is greater than the slot occupancy in the region, it can be obtained that Figure 4 That is, if the boundary groove occupancy rate is larger than the intra-region groove occupancy rate, the area where the gas pressure changes can be reduced near the boundary. Therefore, since the area where the desired gas pressure is achieved can be increased, the temperature of the object W can be effectively controlled. In addition, the in-plane distribution of the temperature of the object W can be suppressed.

[0119] Fig. 9 (a) is a schematic cross-sectional view for illustrating the arrangement of the gas introduction holes 15 .

[0120] exist Fig. 9 In (a), in the X direction, the region 100a is adjacent to the region 100b1, and the region 100a is adjacent to the region 100b2. In addition, in the X direction, two grooves 14a (boundary grooves) are provided at the boundaries between the region 100a and the regions 100b1 and 100b2. In addition, grooves 14b (intra-region grooves) are provided inside the region 100a and inside the regions 100b1 and 100b2. In the region 100a, the gas introduction hole 15 is connected to the groove 14a on the region 100b1 side, and the gas introduction hole 15 is not connected to the groove 14a on the region 100b2 side. In the region 100b1, the gas introduction hole 15 is connected to the groove 14a on the region 100a side. In the region 100b2, the gas introduction hole 15 is connected to the groove 14a on the region 100a side. That is, in the region 100a, the gas introduction hole 15 is connected to only one groove 14a.

[0121] Furthermore, the pressure of the gas supplied to the grooves 14a provided in the region 100a is referred to as P1, and the pressure of the gas supplied to the grooves 14a provided in the regions 100b1 and 100b2 is referred to as P2.

[0122] Fig. 9 (b) is a schematic cross-sectional view for illustrating the arrangement of the gas introduction holes 15 according to another embodiment.

[0123] exist Fig. 9 In (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.

[0124] Furthermore, the pressure of the gas supplied to the grooves 14a provided in the region 100a is referred to as P1, and the pressure of the gas supplied to the grooves 14a provided in the regions 100b1 and 100b2 is referred to as P2.

[0125] Fig.10 (a) Fig.10 (b) is a graph showing the pressure of region 100a, the pressure of regions 100b1 and 100b2, and the pressure of the boundary between region 100a and regions 100b1 and 100b2 obtained by simulation. In the simulation, an object W supported by dots 13 is simulated above the first main surface 11a of the ceramic dielectric substrate 11.

[0126] Fig.10 (a) Fig. 9 (a) Situation.

[0127] Fig.10 (b) Fig. 9 (b) situation.

[0128] Furthermore, P1=3×P2 is set, and the size of the region 100a in the X direction is set to 50 mm.

[0129] like Fig. 9 As shown in (a), since the gas introduction hole 15 is not connected to the groove 14a on the region 100b2 side of the region 100a, Fig.10 (a) It can be seen that the area where the gas pressure changes becomes larger near the boundary. Therefore, the area where the expected gas pressure is achieved becomes smaller.

[0130] On the other hand, since the gas introduction hole 15 is connected to the groove 14a on the region 100b1 side of the region 100a, Fig.10 (a) It can be seen that the area where the gas pressure changes becomes smaller near the boundary. Therefore, the area where the desired gas pressure is achieved can be enlarged.

[0131] In addition, by Fig.10 (b) It is understood that if the gas introduction holes 15 are connected to each of the two grooves 14a provided with the boundary interposed therebetween, the region where the desired gas pressure is achieved can be further increased, which is more preferable.

[0132] As described above, the temperature of the object W can be controlled by the gas pressure. Therefore, if the area where the desired gas pressure is achieved is enlarged, the temperature of the object W can be effectively controlled. In addition, the occurrence of in-plane distribution in the temperature of the object W can be suppressed.

[0133] 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 with the boundary sandwiched therebetween. Fig. 9 In the example shown in (b), two gas introduction holes 15 are provided in the region 100a. For example, the two gas introduction holes 15 can be connected to one gas supply path 53 (see Figure 1 ) connected.

[0134] In addition, when the gas introduction holes 15 are connected to the two grooves 14a sandwiching the boundary, the angle between the line connecting the centers of the gas introduction hole 15 connected to one groove 14a and the center of the gas introduction hole 15 connected to the other groove 14a and the boundary may be less than 90°. In this case, the angle may be, for example, 1.0° to 89°, preferably 2.0° to 70°, and more preferably 3.0° to 60°.

[0135] In this way, the boundary grooves can be brought closer to each other, and the area where the gas pressure changes can be reduced. Therefore, the area where the desired gas pressure is achieved can be increased.

[0136] The angle formed by the line connecting the centers of the gas introduction hole 15 connected to one groove 14 a and the gas introduction hole 15 connected to the other groove 14 a and the boundary may be 90°.

[0137] In this case, the angle is not strictly 90°, for example, to allow for differences in the degree of manufacturing errors.

[0138] In this way, if the two gas introduction holes 15 are arranged at opposing positions, the gases of different pressures supplied from the two gas introduction holes 15 counteract each other. Therefore, it is easier to maintain the pressure of each region at the target pressure.

[0139] Fig.11 It is a schematic plan view of a ceramic dielectric substrate 11 according to another embodiment. Fig.11 for Figure 2 A schematic plan view of the ceramic dielectric substrate 11 is shown.

[0140] like Fig.11 As shown, a plurality of grooves 14c may be provided on the first main surface 11a of the ceramic dielectric substrate 11. The width of the groove 14c (the dimension in the direction substantially perpendicular to the extending direction of the groove) may be, for example, 0.1 mm or more and 1 mm or less. The depth of the groove 14c (the dimension in the Z direction) may be, for example, 50 μm or more and 150 μm or less.

[0141] In this example, at least one groove 14c is provided in each of the regions 101, 102, and 104. The groove 14c connects the plurality of grooves 14a and 14b provided in one region. Therefore, the 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. Since the flow of gas can be smooth if the groove 14c is provided, the pressure distribution generated in the region can be suppressed even in the absence of a sealing ring. In addition, even if the top of the dot 13 is worn and the gap between the object W and the first main surface 11a is narrowed, the gas can be supplied to the groove 14b and other grooves 14a via the groove 14c.

[0142] The groove 14c is configured to communicate the grooves 14a and 14b. The groove 14c may extend in a direction intersecting the grooves 14a and 14b, for example.

[0143] For example, Fig.12 As shown in FIG. 1 , the plurality of grooves 14c may be provided on a line passing through the center of the ceramic dielectric substrate 11. In addition, the plurality of grooves 14c do not necessarily have to be provided on a line passing through the center of the ceramic dielectric substrate 11. In addition, although a linear groove 14c is illustrated, the groove 14c may be a curved groove 14c or a groove 14c having a linear portion and a curved portion within a range that can communicate with the groove 14a and the groove 14b. The number, arrangement, shape, etc. of the plurality of grooves 14c may be appropriately changed according to the size of the object W, the specification requirements of the temperature distribution on the object W, etc. The number, arrangement, shape, etc. of the plurality of grooves 14c may be appropriately determined, for example, by performing experiments or simulations.

[0144] In the embodiment of the present invention without a seal ring, a study has been conducted to improve the responsiveness of the gas pressure in the region. As an example, the gas pressure in the region can be effectively controlled by providing a groove 14c that communicates with the grooves 14a and 14b.

[0145] In addition, since there is a gap of only the height of the dot 13 between the first main surface 11a and the object W, 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. However, when the top of the dot 13 is worn and the gap between the object W and the first main surface 11a is narrowed, it may cause obstruction of the flow of gas in each area, thereby generating pressure distribution. If the groove 14c is provided, even if the top of the dot 13 is worn and the gap between the object W and the first main surface 11a is narrowed, the gas can be supplied to the groove 14b and other grooves 14a through the groove 14c. Therefore, it is possible to significantly shorten the time until the pressure in the area reaches the specified pressure, or to suppress the pressure distribution in the area.

[0146] In addition, if Fig.11 As shown, at least two gas inlet holes 15 (first gas inlet holes) that can supply gas to the groove 14a (first boundary groove) can be set in the region 101 (first region), and the groove 14a (first boundary groove) is a groove 14a that is set closest to the boundary 102a (first boundary) between the region 101 and the region 102 (second region) and extends along the boundary 102a.

[0147] Recently, the density of semiconductor integrated circuits has been further developed, and the plasma density has also been increased to achieve further fine processing. When the diameter of the gas introduction hole 15 is reduced to suppress arcing under this high-density plasma, individual differences may occur in each gas introduction hole 15 due to manufacturing errors. According to this embodiment, the influence of the error in the diameter of each gas introduction hole 15 can be suppressed, and a gas of a specified flow rate can be more reliably supplied to the groove 14a extending along the boundary 102a.

[0148] In addition, if Fig.11 As shown, at least two gas inlet holes 15 (second gas inlet holes) can be provided in the region 102 to supply gas to the groove 14a (second boundary groove), which is the groove 14a provided closest to the boundary 102a and extending along the boundary 102a. Fig.11 In the example shown, three gas introduction holes 15 are provided.

[0149] In this way, similarly to the above, the influence of the error in the hole diameter of each gas introduction hole 15 can be suppressed, and the gas can be more reliably supplied to the groove 14 a extending along the boundary 102 a .

[0150] Next, the effect of the groove 14c will be further described.

[0151] Fig.12 (a) is a schematic plan view for illustrating the arrangement of the grooves 14 according to the comparative example.

[0152] exist Fig.12 In (a), a plurality of grooves 14 are provided on the surface of the substrate 110. The plurality of grooves 14 are annular and are concentrically arranged with the center 110a of the substrate 110 as the center and at equal intervals. Fig.12 In (a), the groove 14c is not provided.

[0153] Fig.12 (b) is a schematic plan view for illustrating the arrangement of the grooves 14 and the grooves 14c.

[0154] exist Fig.12In (b), a plurality of grooves 14 and a plurality of grooves 14c are provided to connect at least a portion of the plurality of grooves 14. In this example, the grooves 14c are provided on a line passing through the center 110a of the substrate 110. The plurality of grooves 14 are connected to each other via the grooves 14c.

[0155] Fig.13 is a graph for illustrating changes in pressure at the center 110 a of the substrate 110 . Fig.13 Graph 114 is a graph of pressure change on the center 110 a of the substrate 110 obtained by simulation. In the simulation, an object W supported by the dots 13 is simulated above the substrate 110 .

[0156] Fig.13 The E in Fig.12 (a) shows an example in which a plurality of grooves 14 are provided.

[0157] Fig.13 The F in Fig.12 (b) The illustrated case is a case where a plurality of grooves 14 and a plurality of grooves 14c are provided.

[0158] Depend on Fig.13 It is known that in Fig.12 In the case (case E) illustrated in (a), the pressure can only be increased to 95% of the predetermined pressure (20 Torr). This means that there may be a pressure distribution in the region.

[0159] exist Fig.12 In the case (F) exemplified in (b), the pressure can be increased to a predetermined pressure (20 Torr). This means that the pressure distribution in the region can be suppressed.

[0160] In case of F, the time T1 required to increase to the specified pressure is shorter than the time T2 required to increase to 95% of the specified pressure in case of E. This means that the time until the pressure in the region reaches the specified pressure can be greatly shortened, in other words, the responsiveness of gas control and thus temperature control can be improved.

[0161] As described above, it is preferable that the gas introduction hole 15 is connected to at least one of the two grooves 14 a provided between the boundaries 101 a to 103 a .

[0162] For example, Fig.11 As shown, in the regions 101, 102, and 104 inside the first main surface 11a, the gas introduction hole 15 can be connected to the outermost groove 14a in each region. In the outermost region 103 of the first main surface 11a, the gas introduction hole 15 can be connected to the innermost groove 14a.

[0163] The number and arrangement of the gas introduction holes 15 provided in each region may be appropriately changed according to the size of the object W, the specification requirements of the temperature distribution of the object W, etc. Fig.11 As shown, three gas introduction holes 15 may be provided at equal intervals in one region. In this case, at least one of the plurality of gas introduction holes 15 provided in the region 103 may be provided in the region 102 on a line passing through the center of the first main surface 11a.

[0164] The above is a case where the area where the gas pressure changes is reduced near the boundary. However, when considering the supply of gas to the grooves 14a and 14c provided in the area, it is preferable to provide the gas introduction hole 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 introduction hole 15 can overlap with at least one of the grooves 14a and 14c in the portion connecting the grooves 14a and 14c. In this way, it is easy to make the gas supplied to the groove 14a flow out to the groove 14c side. Therefore, it is easy to obtain the effect of the groove 14c described above.

[0165] Fig.14 (a)~ Fig.14 (c) is a schematic diagram for illustrating the form of the groove 14c.

[0166] Fig.14 (b) Yes Fig.14 Enlarged view of part E in (a).

[0167] Fig.14 (c) Yes Fig.14 Enlarged view of part F in (a).

[0168] like Fig.14 As shown in (b), for example, the groove 14c may be provided so as to overlap a line drawn from the center toward the periphery of the ceramic dielectric substrate 11. In this case, the angle between the tangent line of the groove 14a and the groove 14c at the portion connecting the groove 14a and the groove 14c may be 90°.

[0169] In addition, if Fig.14 As shown in (c), the groove 14c may not overlap with a line drawn from the center toward the periphery of the ceramic dielectric substrate 11. In this case, the angle between the tangent line of the groove 14a and the groove 14c at the portion connecting the groove 14a and the groove 14c is not 90°.

[0170] Fig.15 It is a schematic plan view of a ceramic dielectric substrate 11 according to another embodiment.

[0171] exist Fig. 9 and Fig.11In the illustrated example, the first main surface 11a is divided into a plurality of regions 101 to 104 in a concentric circle shape. Fig.15 In the illustrated case, the first main surface 11a is divided into a plurality of regions 105 that fit closely together. The plurality of regions 105 can be arranged side by side. Although there is no particular limitation on the outer shape of the plurality of regions 105, it is preferred that the plurality of regions 105 be formed into a shape that can fit closely together. The plurality of regions 105 can be, for example, a polygon such as a triangle or a quadrangle. Fig.15 The outer shape of the region 105 is a regular hexagon. The outer shapes, number, and arrangement of the plurality of regions 105 may be appropriately changed according to the size of the object W, the specification requirements of the temperature distribution on the object W, and the like. The outer shapes, number, and arrangement of the plurality of regions 105 may be appropriately determined, for example, by performing experiments or simulations.

[0172] The groove 14a is provided along the boundary 105a of the region 105. The groove 14a is provided on both sides sandwiching the boundary 105a. At least one groove 14b is provided in the region 105. The groove 14b can be provided concentrically with the groove 14a. The number and position of the grooves 14b provided in one region can be appropriately changed according to the size of the object W, the specification requirements of the temperature distribution on the object W, etc. The number and position of the grooves 14b provided in one region can be appropriately determined, for example, by performing experiments or simulations.

[0173] The other structures are the same as those described above, and the groove 14c, the gas introduction hole 15, the dot 13, the lift pin hole 16, the outer seal 17, etc. may be provided.

[0174] (Processing device)

[0175] Fig.16 This is a schematic diagram for illustrating the processing device 200 involved in this embodiment.

[0176] like Fig.16 As shown, an electrostatic chuck 1 , a power source 210 , a medium supply unit 220 , and a supply unit 230 may be disposed on a processing device 200 .

[0177] The power supply 210 is electrically connected to the electrode 12 provided on 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. In addition, the power supply 210 may be provided with a switch for switching between application of voltage and stopping application of voltage.

[0178] 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 as a cooling medium or a heat-retaining medium.

[0179] The medium supply unit 220 includes, for example, a storage unit 221 , a control valve 222 , and a discharge unit 223 .

[0180] The storage part 221 may be, for example, a tank for storing liquid, a factory piping, etc. In addition, a cooling device or a heating device for controlling the temperature of the liquid may be provided on the storage part 221. A pump or the like for delivering the liquid may be provided on the storage part 221.

[0181] A 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. In addition, the control valve 222 can switch between supplying and stopping the supply of the liquid.

[0182] The discharge section 223 is connected to the output path 52. The discharge section 223 may be a storage tank, a liquid discharge pipe, or the like for recovering the liquid discharged from the output path 52. In addition, the liquid discharged from the output path 52 may be supplied to the storage section 221, and the discharge section 223 is not necessarily required. In this way, since the cooling medium or the heat-insulating medium can be circulated, resource saving can be achieved.

[0183] The supply unit 230 includes a gas supply unit 231 and a gas control unit 232 .

[0184] The gas supply unit 231 may be a high-pressure gas cylinder storing a gas such as helium, a factory pipe, etc. In addition, although the case where one gas supply unit 231 is provided is illustrated, a plurality of gas supply units 231 may be provided.

[0185] The gas control unit 232 is connected between the plurality of gas supply paths 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. In addition, the gas control unit 232 can also have a function of switching the supply and stop of the gas supply. The gas control unit 232 can be, for example, a mass flow controller, a mass flow meter, etc.

[0186] like Fig.16 As shown, a plurality of gas control units 232 may be provided. For example, a gas control unit 232 may be provided for each of the plurality of regions 101 to 104. In this way, the supplied gas may be controlled for each of the plurality of regions 101 to 104. At this time, a gas control unit 232 may be provided for each of the plurality of gas supply paths 53. In this way, the gas in the plurality of regions 101 to 104 may be controlled more precisely. In addition, although a case where a plurality of gas control units 232 are provided is illustrated, if the gas control unit 232 can independently control the supply of gas in a plurality of supply systems, it may also be a single unit.

[0187] Here, the unit for holding the object W includes a vacuum chuck, a mechanical chuck, etc. However, the vacuum chuck cannot be used in an environment below atmospheric pressure. In addition, when a mechanical chuck is used, the object W may be damaged or particles may be generated. Therefore, an electrostatic chuck is used in a processing device used in a semiconductor manufacturing process, for example.

[0188] In such a processing apparatus, it is necessary to isolate the processing space from the external environment. Therefore, the processing apparatus 200 may further include a chamber 240. The chamber 240 may have an airtight structure capable of maintaining an atmosphere at a pressure lower than the atmospheric pressure, for example.

[0189] In addition, the processing device 200 may include a plurality of lifting pins and a driving device for raising and lowering the plurality of lifting pins. When receiving the object W from the conveying device or delivering the object W to the conveying device, the lifting pins are raised by the driving device and protrude from the first main surface 11a. When the object W received from the conveying device is placed on the first main surface 11a, the lifting pins are lowered by the driving device and are stored inside the ceramic dielectric substrate 11.

[0190] In addition, various devices may be provided in the processing apparatus 200 according to the content of the processing. For example, a vacuum pump or the like for exhausting the interior of the chamber 240 may be provided. A plasma generating device for generating plasma in the interior of the chamber 240 may be provided. A process gas supply unit for supplying process gas to the interior of the chamber 240 may be provided. A heater for heating the object W and the process gas may be provided in the interior of the chamber 240. In addition, the devices provided in the processing apparatus 200 are not limited to the devices illustrated. Since known technologies can be applied to the devices provided in the processing apparatus 200, detailed descriptions thereof are omitted.

[0191] As described above, the processing apparatus 200 according to the present 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. According to the processing apparatus 200 according to the present embodiment, the gas pressure in each area can be set to an appropriate pressure.

[0192] The above is a description of the embodiments of the present invention. However, the present invention is not limited to the above description. For example, although a structure utilizing Coulomb force is illustrated as the electrostatic chuck 1, it may also be a structure utilizing Johnson-Rabbeck force. In addition, with respect to the aforementioned embodiments, as long as they have the features of the present invention, the technology that is appropriately designed and changed by those skilled in the art is also included in the scope of the present invention. In addition, as long as it is technically feasible, the various elements of the aforementioned embodiments may be combined, but as long as they include the features of the present invention, these combined technologies are also included in the scope of the present invention.

Claims

1. An electrostatic chuck, comprising: Base plate; and a ceramic dielectric substrate, which is disposed on the base plate, has a substantially circular planar shape, has a first main surface exposed to the outside, and is characterized in that: The first main surface includes a plurality of dots on which an object can be placed, and includes at least a first region and a second region adjacent to the first region and disposed outside the first region relative to the center of the first main surface. The first region is provided with a plurality of first grooves, at least one first gas introduction hole connected to at least one of the plurality of first grooves, and at least one second groove extending in a direction intersecting the plurality of first grooves. The plurality of first grooves each have a substantially circular planar shape and are concentrically arranged. The plurality of first grooves include a first boundary groove that is provided closest to a first boundary between the first region and the second region and extends along the first boundary. The second area is provided with: Multiple 3rd slots; and at least one second gas introduction hole connected to at least one of the plurality of third grooves; The plurality of third grooves include a second boundary groove that is disposed closest to the first boundary and extends along the first boundary. In a state where the object is placed on the plurality of dots, a space is formed between the first main surface and the object so that the gas supplied to one of the first boundary groove and the second boundary groove is supplied to the other. The second groove is connected to at least two of the first grooves, When projected onto a plane perpendicular to a first direction from the base plate toward the ceramic dielectric substrate, at least a portion of the first gas introduction hole overlaps the first boundary groove and the second groove at a portion connecting the first boundary groove and the second groove.

2. The electrostatic chuck according to claim 1, characterized in that At least two of the second grooves are provided in the first region.

3. The electrostatic chuck according to claim 1, characterized in that In the second region, at least one fourth groove is further provided, the at least one fourth groove extending in a direction intersecting the plurality of third grooves and connected to at least two of the third grooves. The plurality of third grooves each have a substantially circular planar shape and are concentrically arranged around the center of the plurality of first grooves. When projected onto a plane perpendicular to the first direction, at a portion connecting the third groove and the fourth groove, at least a portion of the second gas introduction hole overlaps with at least one of the third groove and the fourth groove.

4. The electrostatic chuck according to claim 3, characterized in that At least two of the fourth grooves are provided in the second region.

5. The electrostatic chuck according to claim 3, characterized in that When projected onto a plane perpendicular to the first direction, in the first region, on a portion connecting the first groove and the second groove located on the outermost side, at least a portion of the first gas inlet hole overlaps with at least any one of the first groove and the second groove located on the outermost side, and in the second region, on a portion connecting the third groove and the fourth groove located on the innermost side, at least a portion of the second gas inlet hole overlaps with at least any one of the third groove and the fourth groove located on the innermost side.

6. The electrostatic chuck according to claim 3, characterized in that An angle formed by a line connecting the center of the first gas introduction hole and the center of the second gas introduction hole and a first boundary between the first region and the second region is smaller than 90°.

7. The electrostatic chuck according to claim 3, characterized in that An angle formed by a line connecting the center of the first gas introduction hole and the center of the second gas introduction hole and a first boundary between the first region and the second region is 90°.

8. The electrostatic chuck according to claim 7, characterized in that It also includes a lifting pin hole provided in the first area, A distance between the lift pin hole and the outermost first groove in the first region is greater than a distance between the lift pin hole and the first groove closest to the lift pin hole except the outermost first groove among the plurality of first grooves.

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