JP2020102617A - Electrostatic chuck - Google Patents

Abstract

To provide an electrostatic chuck capable of suppressing the deposition of particles at a sealing ring portion while effectively controlling the pressure of gas in each region.SOLUTION: In an electrostatic chuck, a ceramic dielectric substrate 11 has a first major surface 11a and a second major surface. The first major surface includes at least a first region 101 and a second region 102. In the first region, there are provided a plurality of first grooves 14a, 14b and at least one first gas introduction hole 15. The plurality of first grooves include: a first boundary groove 14a provided to be most proximal to a first boundary 102a between the first region and the second region; and a first in-region groove 14b. In the second region, there are provided a plurality of second grooves 14a, 14b and at least one second gas introduction hole 15, the plurality of second grooves including a second boundary groove 14a. A boundary groove occupancy ratio in a first area C where the first boundary and the first and second boundary grooves are included is larger than an in-region groove occupancy ratio in a second area D1.SELECTED DRAWING: Figure 11

Description

Aspects of the invention relate to electrostatic chucks.

The electrostatic chuck has, for example, a ceramic dielectric substrate made of alumina or the like, and an electrode provided inside the ceramic dielectric substrate. When electric power is applied to the electrodes, electrostatic force is generated. The electrostatic chuck attracts an object such as a silicon wafer by the generated electrostatic force. In such an electrostatic chuck, an inert gas (hereinafter, simply referred to as gas) such as helium (He) is flown between the front surface of the ceramic dielectric substrate and the back surface of the target object, The temperature is controlled.

For example, in an apparatus for processing a substrate such as a CVD (Chemical Vapor Deposition) apparatus, a sputtering apparatus, an ion implantation apparatus, or an etching apparatus, the temperature of the substrate may rise during the processing. Therefore, in the electrostatic chuck used in such an apparatus, gas is made to flow between the ceramic dielectric substrate and the substrate, and the gas is brought into contact with the substrate to radiate heat from the substrate.

Further, during the processing, a temperature distribution occurs in the surface of the object. In this case, the higher the gas pressure, the greater the amount of heat released from the object, so the temperature of the object can be lowered. Therefore, the surface of the ceramic dielectric substrate on the object side is divided into a plurality of regions, and the in-plane temperature of the object is controlled by changing the gas pressure in the plurality of regions.

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 area, it is preferable that each area be airtightly partitioned by a seal ring. However, in this case, particles generated in the wafer processing process are likely to be accumulated in the seal ring portion, which may cause a defect such as a defect in the portion.

A technique has also been proposed in which a slight gap is provided between the top of the seal ring and the object to control the gas pressure in each region (see Patent Document 2).
Even in this case, the problem that particles are likely to accumulate in the seal ring portion has not been solved yet.
Therefore, it has been desired to develop a technique capable of suppressing the deposition of particles in the seal ring portion while effectively controlling the gas pressure in each region.

JP, 2011-119708, A JP 2012-129547 A

The present invention has been made based on the recognition of such a problem, and provides an electrostatic chuck capable of suppressing the accumulation of particles in a seal ring portion while effectively controlling the gas pressure in each region. The purpose is to

A first invention comprises a base plate and a ceramic dielectric substrate provided on the base plate and having a first main surface exposed to the outside, the first main surface being at least a first region (region). 101) and a second area (area 102) adjacent to the first area, and a plurality of first grooves (grooves 14a, 14b) in the first area of the first main surface, and At least one first gas introduction hole (gas introduction hole 15) connected to at least one of the plurality of first grooves, and the plurality of first grooves include the first region and the second region. A first boundary groove (a groove 14a) that is provided closest to the first boundary (border 102a) and extends along the first boundary, and at least one first region different from the first boundary groove. An inner groove (groove 14b), and a plurality of second grooves (grooves 14a, 14b) and at least one of the plurality of second grooves are connected to the second region of the first main surface. At least one second gas introduction hole (gas introduction hole 15) is provided, and the plurality of second grooves are provided closest to the first boundary and extend along the first boundary. Boundary groove occupancy in the first range (range C1) including the boundary groove (groove 14a), having a predetermined unit area, and including the first boundary, the first boundary groove, and the second boundary groove The ratio is larger than the area groove occupancy rate in the second range (ranges D and D1) including the first area groove and having the same shape and size as the first area. It's a chuck.

This electrostatic chuck does not have a seal ring arranged between the regions in order to control the gas pressure in each region as in the conventional case. That is, when the object W is installed, the object W and the ceramic dielectric substrate (first region and second region) form one closed space. Therefore, it is possible to solve the problem that particles are accumulated in the seal ring portion. On the other hand, if the seal ring is not simply provided, it becomes difficult to divide the gas pressure in each region, and the gas pressure controllability is degraded. Therefore, in the present invention, not only the seal ring is eliminated, but the distance between the groove end portions between the first boundary groove and the second boundary groove is set within the first area adjacent to the first boundary groove and the first boundary groove. It is devised so that it is smaller than the distance between the groove ends with the groove.
Further, according to this electrostatic chuck, the region where the gas pressure changes can be reduced in the vicinity of the boundary between the regions, so that the region where the intended gas pressure is achieved can be increased. Therefore, it is possible to effectively control the gas pressure in each region while solving the problem that particles are deposited.

In a second aspect based on the first aspect, a distance between groove ends between the first boundary groove and the second boundary groove is smaller than a distance between groove ends between the first area grooves. The electrostatic chuck is characterized in that

According to this electrostatic chuck, the gas pressure in each region can be controlled more effectively.

In a third aspect based on the first or second aspect, when projected onto a plane perpendicular to the first direction from the base plate to the ceramic dielectric substrate, at least a part of the first gas introduction hole is: The electrostatic chuck is characterized in that it overlaps with the first boundary groove.

In this electrostatic chuck, the first boundary groove and the first gas introduction hole are directly communicated with each other, so that the gas controllability is excellent. Therefore, in the vicinity of the boundary between the areas, the area where the gas pressure changes can be made smaller.

In a fourth aspect based on any one of the first to third aspects, when projected onto a plane perpendicular to the first direction from the base plate to the ceramic dielectric substrate, at least the second gas introduction hole is formed. Part of the electrostatic chuck is characterized by overlapping with the second boundary groove.

According to this electrostatic chuck, the region where the gas pressure changes can be made smaller in the vicinity of the boundary between the regions.

5th invention is an invention which in any one of 1st-4th invention makes the angle which the line which connects the center of the said 1st gas introduction hole and the center of the said 2nd gas introduction hole, and the said 1st boundary. Is less than 90°, which is an electrostatic chuck.

According to this electrostatic chuck, the boundary grooves can be brought closer to each other, and the region where the gas pressure changes can be reduced. Therefore, the region where the intended gas pressure is achieved can be increased.

6th invention is an angle which the line which connects the center of the said 1st gas introduction hole and the center of the said 2nd gas introduction hole, and the said 1st boundary in any one of 1st-4th invention. Is 90°, which is an electrostatic chuck.

According to this electrostatic chuck, the pressure in each region can be easily maintained at the target pressure.

7th invention is any 1st-6th invention, Comprising: The lift pin hole provided in the said 1st main surface is further provided, The distance between the said lift pin hole and the said 1st boundary groove is, The electrostatic chuck is characterized in that it is larger than a distance between the lift pin hole and the first region inner groove closest to the lift pin hole.

According to this electrostatic chuck, it is possible to reduce the pressure change in the area.

In an eighth invention according to any one of the first to seventh inventions, the first main surface is at least the first region, the second region located outside the first region, and the first region. A third region (region 103) located outside the second region and adjacent to the second region, wherein the plurality of second grooves are second regions between the second region and the third region. A second outer boundary groove (groove 14a) that is provided closest to the boundary and extends along the second boundary, and is provided in the third region adjacent to the second boundary; A third boundary groove (groove 14a) extending along the boundary is provided, has a predetermined unit area, and includes the second boundary, the second boundary groove, and the third boundary groove. The boundary groove occupancy in the range (range C2) is larger than the in-region groove occupancy in the first range (range C1).

According to this electrostatic chuck, the region where the gas pressure changes can be made smaller in the vicinity of the boundary between the regions.

In a ninth aspect based on the eighth aspect, further comprising an outer seal that is provided so as to surround the peripheral edge of the first main surface, at least a portion of which is capable of contacting an object to be attracted, and the base plate to the ceramic dielectric In a second direction orthogonal to the first direction toward the body substrate, a distance between the second boundary and the outer seal is smaller than a distance between the first boundary and the second boundary. A characteristic electrostatic chuck.

According to this electrostatic chuck, the region where the gas pressure changes can be made smaller in the vicinity of the boundary between the regions.

According to the aspects of the present invention, there is provided an electrostatic chuck capable of suppressing the accumulation of particles in the seal ring portion while effectively controlling the gas pressure in each region.

It is a schematic cross section for illustrating the electrostatic chuck concerning this embodiment. It is a schematic cross section for illustrating a ceramic dielectric substrate, an electrode, and the 1st porous part. FIG. 6A is a schematic cross-sectional view for illustrating the arrangement of grooves and the arrangement of gas introduction holes according to a comparative example. (B) is a schematic cross-sectional view for illustrating an example of the arrangement of grooves and the arrangement of gas introduction holes according to the present embodiment. It is a graph figure which calculated pressure of a field and pressure of a field and the boundary of a field by simulation. It is a graph figure for illustrating the effect of boundary groove interval. (A) is a graph for exemplifying the effect of the boundary groove interval by the "tilt deviation rate". (B) is a graph for explaining the "tilt deviation rate". It is an enlarged view of the H section in Fig.6 (a). It is a graph for illustrating the effect of the number of the 2nd grooves (grooves 14a and 14b). FIG. 6A is a schematic cross-sectional view for illustrating the arrangement of gas introduction holes. (B) is a schematic cross section for illustrating the arrangement of the gas introduction holes according to another embodiment. (A), (b) is a graph which calculated|required the pressure of the area|region and the pressure of the boundary of the area|region by the simulation. It is a schematic plan view of the ceramic dielectric substrate which concerns on other embodiment. FIG. 6A is a schematic plan view for illustrating the arrangement of grooves according to a comparative example. (B) is a schematic plan view for illustrating the arrangement of the grooves. It is a graph figure for illustrating pressure change in the center of a substrate. (A)-(c) is a schematic diagram for illustrating the form of the groove 14c. It is a schematic plan view of the ceramic dielectric substrate which concerns on other embodiment. It is a schematic diagram for illustrating the processing apparatus according to the present embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same components are designated by the same reference numerals, and detailed description thereof will be appropriately omitted.
In each drawing, the direction from the base plate 50 to the ceramic dielectric substrate 11 is the Z direction, one direction substantially orthogonal to the Z direction is the Y direction, and the direction substantially orthogonal to the Z direction and the Y direction is the X direction. There is.

(Electrostatic chuck)
FIG. 1 is a schematic cross-sectional view for illustrating the electrostatic chuck 1 according to this embodiment.
FIG. 2 is a schematic cross-sectional view for illustrating the ceramic dielectric substrate 11, the electrode 12, and the first porous portion 90.
As shown in FIG. 1, the electrostatic chuck 1 may be provided with a ceramic dielectric substrate 11, an electrode 12, a first porous portion 90, a base plate 50, and a second porous portion 70.

As shown in FIGS. 1 and 2, the ceramic dielectric substrate 11 may be a flat plate-shaped member made of sintered ceramics, for example. For example, the ceramic dielectric substrate 11 may include aluminum oxide (Al ₂ O ₃ ). 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 set to, for example, 99 atomic percent (at% mic%) or more and 100 at% mic% 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 can be set to, for example, 1% or less. The density of the ceramic dielectric substrate 11 can be set to 4.2 g/cm ³ , for example.

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 11 a is a 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 or a glass substrate.

A plurality of dots 13 are provided on the first main surface 11 a of the ceramic dielectric substrate 11. The target object W is placed on the plurality of dots 13 and supported by the plurality of dots 13. If the plurality of dots 13 are provided, a space is formed between the back surface of the target object W placed on the electrostatic chuck 1 and the first main surface 11a. By appropriately selecting the height and the number of the dots 13, the area ratio of the dots 13, the shape, etc., for example, the particles adhering to the target W can be brought into a preferable state. For example, the height (dimension in the Z direction) of the plurality of dots 13 can be 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.

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 of the groove 14a (dimension in the X direction or the Y direction) is, 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, more preferably 0.2 mm or more and 0.5 mm or less. be able to. 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 is, 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. it can.

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 passage 53 described later via the first porous portion 90. The gas introduction hole 15 is provided from the second main surface 11b to the first main surface 11a. That is, the gas introduction hole 15 extends in the Z direction between the second main surface 11b side and the first main surface 11a side and penetrates the ceramic dielectric substrate 11. The diameter of the gas introduction hole 15 can be, for example, 0.05 mm or more and 0.5 mm or less.
Details of the plurality of grooves 14a and 14b and the plurality of gas introduction holes 15 will be described later.

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 shape of the electrode 12 may be, for example, a thin film shape 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 monopolar or bipolar. The electrode 12 illustrated in FIG. 1 is a bipolar type, and the bipolar electrode 12 is provided on the same surface.

The electrode 12 is provided with a connecting portion 20. The electrode 12 and the connection portion 20 can be formed of a conductive material such as metal. The end portion of the connecting portion 20 opposite to the electrode 12 side can be exposed to the second main surface 11b side of the ceramic dielectric substrate 11. The connection 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 connection part 20 may be a metal terminal connected by an appropriate method such as brazing.

A power supply 210 is electrically connected to the electrode 12 via the connecting portion 20. By applying a predetermined voltage to the electrode 12, it is possible to generate charges in the region of the electrode 12 on the first major surface 11a side. Therefore, the object W is adsorbed and held on the first main surface 11a side of the ceramic dielectric substrate 11 by electrostatic force.

The first porous portion 90 is provided inside the ceramic dielectric substrate 11. The first porous portion 90 can be provided, for example, in the Z direction between the base plate 50 and the first main surface 11a of the ceramic dielectric substrate 11 and at a position facing the gas supply passage 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 in a part of the gas introduction hole 15.

In the case of the first porous portion 90 illustrated in FIGS. 1 and 2, the first porous portion 90 is provided in the portion of the gas introduction hole 15 on the second main surface 11b side. 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. The other end of the first porous portion 90 may be exposed on the bottom surface of the groove 14a. Further, both ends of the first porous portion 90 may be located between the first main surface 11a and the second main surface 11b.

The material of the first porous portion 90 can be, for example, insulating ceramics. The first porous portion 90 includes, for example, at least one of aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO ₂ ) and yttrium oxide (Y ₂ O ₃ ). By doing so, the first porous portion 90 having high withstand voltage and high rigidity can be obtained.

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. By doing so, it is possible to secure the performance such as plasma resistance of the electrostatic chuck 1 and the mechanical strength of the first porous portion 90. As an example, by adding a trace amount of additive to the first porous portion 90, the sintering of the first porous portion 90 is promoted, and it becomes possible to control the pores and ensure the mechanical strength.

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

As shown in FIG. 1, the base plate 50 supports, for example, the ceramic dielectric substrate 11. The ceramic dielectric substrate 11 can be bonded onto the base plate 50, for example. The adhesive can be, for example, a silicone adhesive or the like.

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

The base plate 50 also serves to adjust the temperature of the dielectric substrate 11. For example, when cooling the dielectric substrate 11, the cooling medium is introduced from the input path 51, passed through the connection path 55, and discharged from the output path 52. As a result, the heat of the base plate 50 can be absorbed by the cooling medium, and the ceramic dielectric substrate 11 mounted thereon can be cooled. In addition, when the dielectric substrate 11 is kept warm, it is possible to flow a heat keeping medium into the connection path 55. If the temperature of the dielectric substrate 11 can be controlled, it becomes easy to control the temperature of the object W adsorbed and held on the dielectric substrate 11.

Gas is supplied to the plurality of grooves 14a and 14b. The temperature of the target object W is controlled by the supplied gas coming into contact with the target 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 and 14b can be reduced. For example, the temperature of the target object W can be roughly controlled by the base plate 50, and the temperature of the target object W can be precisely controlled by the gas supplied to the grooves 14a and 14b.

A plurality of gas supply passages 53 can be provided in the base plate 50. The gas supply passage 53 can be provided so as to penetrate the base plate 50. The gas supply path 53 may be provided up to the ceramic dielectric substrate 11 side by branching from the other gas supply path 53 without penetrating the base plate 50.

The gas supply path 53 is connected to the gas introduction hole 15. That is, the gas flowing into the gas supply passage 53 passes through the gas supply passage 53 and then flows into the gas introduction hole 15.

The gas flowing into the gas introducing hole 15 passes through the gas introducing hole 15 and then flows into the groove 14 a to which the gas introducing hole 15 is connected. Thereby, the object W can be directly cooled by the gas.

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

Next, the plurality of grooves 14a, 14b and the plurality of 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 plurality of grooves 14a and 14b. During the processing of the object W, a temperature distribution may occur in the plane of the object W. For example, a low temperature region or a high temperature region may occur in the surface of the object W. In this case, if the pressure of the gas contacting the high temperature region is set higher than the pressure of the gas contacting the low temperature region, the amount of heat released from the high temperature region increases, so that the temperature of the object W is reduced. It is possible to control and suppress the occurrence of temperature distribution in the surface of the object W.

For example, the in-plane temperature of the object W can be controlled by dividing the first main surface 11a side of the ceramic dielectric substrate 11 into a plurality of regions and changing the pressure of the gas supplied to the plurality of regions. .. In this case, in order to control the gas pressure in each region, a seal ring may be provided between the regions so that the regions are partitioned. 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, the gas flow between the regions can be almost eliminated, and the gas pressure in each region can be effectively controlled.

However, when the seal ring is provided, particles generated in the wafer processing process easily accumulate in the seal ring portion, which may cause a defect such as a defect in the portion.

Therefore, in the present invention, the arrangement of the grooves 14a and 14b is devised without providing a seal ring for dividing the regions. That is, when the target object W is installed, the target object W and the ceramic dielectric substrate 11 (for example, the region 101 and the region 102) form a closed space. According to the present invention, it is possible to effectively control the pressure in the region, even though there is no seal ring.
Further, in the present invention, it suffices that the pressure of the gas in each region can be effectively controlled without substantially providing the seal ring, and it does not prevent provision of the seal ring partially or locally. .. That is, the seal ring may be partially or locally provided as long as the effect of effectively controlling the gas pressure in each region is obtained without substantially providing the seal ring.
FIG. 3A is a schematic sectional view for illustrating the arrangement of the grooves 14 and the arrangement of the gas introduction holes 15 according to the comparative example.
In FIG. 3A, 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.

In the present specification, the distance between the groove ends means the distance between the inner wall of the one groove and the inner wall of the other groove, and the inner wall of the other groove when the two adjacent grooves are present. The shortest distance between them. In this case, when the distance between the groove ends of the two grooves changes, the shortest distance can be set as the distance between the groove ends.

In the X direction, the area 100a and the area 100b1, and the area 100a and the area 100b2 are adjacent to each other. In the example illustrated in FIG. 3A, the gas introduction hole 15 is connected to the two grooves 14 provided on both sides of the boundary between the region 100a and the region 100b1.

Further, the pressure of the gas supplied to the groove 14 provided in the region 100a is P1, the pressure of the gas supplied to the groove 14 provided in the region 100b1 is P2, and the pressure of the gas supplied to the groove 14 provided in the region 100b2 is supplied. The gas pressure is P3.

FIG. 3B 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 this embodiment. The groove 14a is a boundary groove provided so as to sandwich the boundary between different regions, and the groove 14b is an in-region groove other than the groove 14a provided in the region.
In FIG. 3B, the distance between the groove ends (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 L21. The distance between the groove ends (inter-region groove interval) between the (boundary groove) and the groove 14b (in-region groove) adjacent to the boundary groove 14a other than the groove 14a provided in the region 100a is L22. In this case, L21<L22. The distance between the groove ends of the groove 14a (boundary groove) and the groove 14b adjacent to the boundary groove 14a other than the groove 14a provided in the regions 100b1 and 100b2 is L24.
Further, the pressure of the gas supplied to the groove 14a provided in the region 100a via the gas introduction hole 15 is P1, and the pressure of the gas supplied to the groove 14a provided in the region 100b1 is P2.

FIG. 4 is a graph diagram obtained by simulating the pressure in the region 100a, the pressure in the regions 100b1 and 100b2, and the pressure at the boundary between the region 100a and the regions 100b1 and 100b2. In the simulation, the object W supported by the dots 13 is assumed to be 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 grooves 14 illustrated in FIG. 3A, the arrangement of the gas introduction holes 15, and the boundary groove interval are equal to the in-region groove interval.
B in FIG. 4 is an example when the groove 14a and the groove 14b illustrated in FIG. 3B are arranged, the gas introduction holes 15 are arranged, and the boundary groove interval is smaller than the in-region groove interval. No seal ring is provided between the regions in any of the examples.
In the simulation, P1=3×P2, the groove end distance L21 is 5 mm, the groove end distance L22 is 20 mm, and the groove end distance L23 is 15 mm. The size of the region 100a in the X direction is 50 mm.

As can be seen from FIG. 4, when the boundary groove interval is equal to the in-region groove interval (in the case of A), the region where the gas pressure changes is large in the vicinity of the boundary between the region 100a and the regions 100b1 and 100b2. Become. On the other hand, when the boundary groove interval is smaller than the in-region groove interval (in the case of B), the region in which the gas pressure changes near the boundary between the region 100a and the regions 100b1 and 100b2 is smaller than that in the case of A. Can be made smaller. That is, in any of the region 100a and the regions 100b1 and 100b2, the region having the intended gas pressure can be increased, and the uniformity of the gas pressure in the region can be improved.

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 the seal ring is not provided between the regions. Therefore, if the uniformity of the gas pressure in the area can be improved, the temperature of the object W in the portion corresponding to the area can be controlled more effectively. In addition, it is possible to prevent the temperature of the object W from having an in-plane distribution.

Further, according to the knowledge obtained by the present inventors, the above effect can be obtained if the gas introduction hole 15 is connected to at least one of the two grooves 14a which are boundary grooves provided with the boundary therebetween. It is preferable because it can be obtained.

In this case, since there is a gap between the first main surface 11a and the object W by the height of the dot 13, the gas supplied to the groove 14a to which the gas introduction hole 15 is connected passes through the gap. It is supplied to the groove 14b and the other groove 14a. That is, in each region, 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.

Further, as illustrated in FIG. 3B, when the gas introduction hole 15 is connected to each of the two grooves 14a provided on both sides of the boundary, the change in gas pressure at the area boundary is suppressed. It is more preferable because the temperature can be made more remarkable and the temperature of the object W can be controlled more effectively. Further, it is possible to more effectively suppress the occurrence of the in-plane distribution in the temperature of the object W.

FIG. 5 is a graph for illustrating the effect of the boundary groove spacing.
The boundary groove interval on the horizontal axis is a distance between groove end portions of two grooves (boundary grooves) provided with a boundary between adjacent regions sandwiched therebetween. The effect of the boundary groove interval is the effect of the boundary groove interval itself, and for example, the distance L23 illustrated in FIG. 3A or the distance L21 illustrated in FIG. 3B can be applied.
The deviation rate on the vertical axis represents how much the average pressure in each region is dissociated from the set pressure (intended pressure). It indicates that the greater the deviation rate, the greater the difference between the average pressure and the intended pressure in each region.
In FIG. 5, for example, the deviation P is obtained by simulation with the pressure P1 in the region 100a in FIGS. 3A and 3B set to 20 Torr (2666.4 Pa) and the pressure P3 in the region 100b2 set to 60 Torr (7999.2 Pa). It is a thing.

As can be seen from FIG. 5, when the boundary groove interval, which is the distance between the groove end portions of the boundary groove, is more than 0 mm and 60 mm or less, preferably more than 0 mm and 20 mm or less, the deviation rate increases almost linearly. If the boundary groove spacing exceeds 60 mm, the deviation rate exponentially increases. This means that if the boundary groove interval is 60 mm or less, preferably 20 mm or less, the increase in the deviation rate can be suppressed, and the average pressure in each region becomes close to the intended pressure.
As described above, the effect of the boundary groove interval is the effect of the boundary groove interval itself. Therefore, the arrangement of the grooves 14a and 14b described above and the arrangement of the gas introduction holes 15 described above (the gas introduction holes 15 in the boundary groove are By appropriately combining the grooves 14c described later, it is possible to effectively control the gas pressure in each region and effectively suppress the accumulation of particles in the seal ring portion.

FIG. 6A is a graph for illustrating the effect of the boundary groove interval by the “tilt deviation rate”.
FIG. 6B is a graph diagram for explaining the “inclination deviation rate”.
FIG. 7 is an enlarged view of the H portion in FIG.
If the pressure in the first region and the pressure in the second region are ideally divided, the pressure distribution at the first boundary between the first region and the second region is as shown in FIG. 6(b). , Distributed on a straight line (changes linearly). Therefore, if the slope is calculated arithmetically from the pressure distribution between the regions obtained by the analysis and the deviation ratio (slope deviation ratio) between this and the ideal slope is calculated, the effect of the boundary groove interval can be evaluated. it can.

As can be seen from FIG. 6A, when the boundary groove interval, which is the distance between the groove ends of the boundary groove, exceeds 0 mm and is 60 mm or less, the inclination deviation rate increases almost linearly. If the boundary groove spacing exceeds 60 mm, the tilt deviation rate increases exponentially. This means that if the interval between the boundary grooves is 60 mm or less, the increase in the inclination deviation rate can be suppressed, and the average pressure in each region becomes close to the intended pressure.
Furthermore, as can be seen from FIG. 7, if the boundary groove interval, which is the distance between the groove end portions of the boundary groove, exceeds 0 mm and is 20 mm or less, the inclination deviation rate can be made closer to linear. This means that if the interval between the boundary grooves is 20 mm or less, the increase in the tilt deviation rate can be further suppressed, and the average pressure in each region becomes closer to the intended pressure.

FIG. 8 is a graph for illustrating the effect of the number of second grooves (grooves 14a and 14b (radial grooves)).
As can be seen from FIG. 8, if at least two second grooves are provided in the second region, the deviation rate can be markedly reduced. That is, the pressure at the first boundary (boundary 102a) between the first area (area 101) and the second area (area 102) may be brought close to the average value of the pressure in the first area and the pressure in the second area. it can. Therefore, it becomes easier to keep the pressure in each region at the target pressure.

According to the knowledge obtained by the present inventors, if the boundary groove occupancy rate is larger than the in-region groove occupancy rate, the effect illustrated in FIG. 4 can be obtained. That is, if the boundary groove occupancy rate is higher than the in-area groove occupancy rate, it is possible to reduce the area where the gas pressure changes near the boundary. Therefore, the region where the intended gas pressure is achieved can be increased, so that the temperature of the object W can be effectively controlled. In addition, it is possible to prevent the temperature of the object W from having an in-plane distribution.

FIG. 9A is a schematic cross-sectional view for illustrating the arrangement of the gas introduction holes 15.
In FIG. 9A, the region 100a and the region 100b1, and the region 100a and the region 100b2 are adjacent to each other in the X direction. Further, two grooves 14a (boundary grooves) are provided across the boundary between the region 100a and the regions 100b1 and 100b2 in the X direction. Further, a groove 14b (in-region groove) is 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.
Further, the pressure of the gas supplied to the groove 14a provided in the region 100a is P1, and the pressure of the gas supplied to the groove 14a provided in the regions 100b1 and 100b2 is P2.

FIG. 9B is a schematic cross-sectional view for illustrating the arrangement of the gas introduction holes 15 according to another embodiment.
In FIG. 9B, in the region 100a, the gas introduction hole 15 is connected to the groove 14a on the region 100b1 side and the groove 14a on the region 100b2 side.
Further, the pressure of the gas supplied to the groove 14a provided in the region 100a is P1, and the pressure of the gas supplied to the groove 14a provided in the regions 100b1 and 100b2 is P2.

FIGS. 10A and 10B are graphs of the pressure in the region 100a, the pressure in the regions 100b1 and 100b2, and the pressure at the boundary between the regions 100a and 100b1 and 100b2 obtained by simulation. In the simulation, the object W supported by the dots 13 is assumed to be above the first main surface 11a of the ceramic dielectric substrate 11.
FIG. 10A shows the case of FIG. 9A.
FIG. 10B is the case of FIG. 9B.
Further, P1=3×P2, and the size of the region 100a in the X direction is 50 mm.

As shown in FIG. 9A, the gas introduction hole 15 is not connected to the groove 14a on the region 100b2 side of the region 100a. Therefore, as can be seen from FIG. The area in which changes occur becomes large. Therefore, the area where the intended gas pressure is achieved becomes smaller.
On the other hand, on the region 100a side of the region 100a, since the gas introduction hole 15 is connected to the groove 14a, as can be seen from FIG. 10A, there is a region where the gas pressure changes near the boundary. Get smaller. Therefore, the area where the intended gas pressure is achieved can be increased.
Further, as can be seen from FIG. 10B, by connecting the gas introduction hole 15 to each of the two grooves 14a provided on both sides of the boundary, the region where the intended gas pressure is achieved can be further increased. , And more preferable.

As described above, the temperature of the object W can be controlled by the gas pressure. Therefore, if the region where the intended gas pressure is achieved can be increased, the temperature of the object W can be effectively controlled. In addition, it is possible to prevent the temperature of the object W from having an in-plane distribution.
As described above, the gas introduction hole 15 is preferably connected to the groove 14a (boundary groove). Further, the gas introduction hole 15 is more preferably connected to each of the two grooves 14a provided with the boundary therebetween. In addition, in the example shown in FIG. 9B, two gas introduction holes 15 are provided in the region 100a. For example, both of the two gas introduction holes 15 may communicate with one gas supply passage 53 (see FIG. 1).

When connecting the gas introduction hole 15 to each of the two grooves 14a provided on both sides of the boundary, the center of the gas introduction hole 15 connected to the one groove 14a and the center of the gas introduction hole 15 connected to the other groove 14a are connected. The angle formed by the line connecting the center of the gas introduction hole 15 and the boundary can be less than 90°. In this case, the angle can be, for example, 1.0° or more and 89° or less, preferably 2.0° or more and 70° or less, and more preferably 3.0° or more and 60° or less.
With this configuration, the boundary grooves can be brought closer to each other, and the region where the gas pressure changes can be reduced. Therefore, the area where the intended gas pressure is achieved can be increased.

The angle formed by the line connecting the center of the gas introduction hole 15 connected to the one groove 14a and the center of the gas introduction hole 15 connected to the other groove 14a and the boundary can be 90°. .. In this case, the angle is not limited to 90° in a strict sense, and for example, a difference in manufacturing error degree is allowed.
Thus, if the two gas introduction holes 15 are arranged at opposite positions, the gases supplied from the two gas introduction holes 15 and having different pressures compete with each other. Therefore, it becomes easier to keep the pressure in each region at the target pressure.

FIG. 11 is a schematic plan view of a ceramic dielectric substrate 11 according to another embodiment. FIG. 11 is a schematic plan view of the ceramic dielectric substrate 11 shown in FIG.
As 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 groove 14c (dimension in a direction substantially perpendicular to the extending direction of the groove) can be, for example, 0.1 mm or more and 1 mm or less. The depth (dimension in the Z direction) of the groove 14c can be, for example, 50 μm or more and 150 μm or less.

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 to which the gas introduction hole 15 is connected flows along the groove 14a and is supplied to the groove 14b and another groove 14a via the groove 14c. Since the gas flow can be made smooth if the groove 14c is provided, it is possible to suppress the occurrence of pressure distribution in the region even when there is no seal ring. Further, even if the tops of the dots 13 are 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 the other groove 14a via the groove 14c.

The groove 14c is arranged so that the groove 14a and the groove 14b communicate with each other. The groove 14c can extend in a direction intersecting with the grooves 14a and 14b, for example.
For example, as shown in FIG. 11, the plurality of grooves 14c can be provided on a line passing through the center of the ceramic dielectric substrate 11. The plurality of grooves 14c need not necessarily be provided on a line passing through the center of the ceramic dielectric substrate 11. Further, although the 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 in a range in which the groove 14c can communicate with the groove 14a and the groove 14b. You can The number, arrangement, shape, etc. of the plurality of grooves 14c can be appropriately changed according to the size of the object W, the required specifications of the temperature distribution in the object W, and the like. The number, arrangement, shape, etc. of the plurality of grooves 14c can be appropriately determined by, for example, performing an experiment or a simulation.

In the embodiment of the present invention in which the seal ring is not provided, it is devised in order to enhance the responsiveness of the gas pressure in the area. As an example thereof, the gas pressure in the region can be effectively controlled by providing the groove 14c that connects the groove 14a and the groove 14b.
Further, since there is a gap between the first main surface 11a and the object W by the height of the dot 13, the gas supplied to the groove 14a to which the gas introduction hole 15 is connected will not pass through the gap. 14b and other grooves 14a. However, if the tops of the dots 13 are worn and the gap between the object W and the first main surface 11a becomes narrow, the gas flow in each region may be obstructed, and pressure distribution may occur. 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 becomes narrow, the groove 14b and the other groove 14a are provided via the groove 14c. Can be supplied with gas. Therefore, it is possible to significantly shorten the time until the pressure in the region reaches a predetermined pressure, and to suppress the occurrence of pressure distribution in the region.

Further, as shown in FIG. 11, the area 101 (first area) is provided closest to the boundary 102a (first boundary) between the area 101 and the area 102 (second area). At least two gas introduction holes 15 (first gas introduction holes) capable of supplying gas can be provided in the groove 14a (first boundary groove) extending along the groove 102a.
In recent years, the density of semiconductor integrated circuits has been further increased, and the plasma density has also been increased in order to achieve further fine processing. If the diameter of the gas introduction hole 15 is reduced in order to suppress the arcing under the high density plasma, individual differences may occur in the individual gas introduction holes 15 due to manufacturing variations and the like. According to the present embodiment, it is possible to suppress the influence of the variation in the hole diameter of each gas introduction hole 15 and to more reliably supply the gas of a predetermined flow rate to the groove 14a extending along the boundary 102a.

Further, as shown in FIG. 11, in the region 102, the gas introduction hole 15 capable of supplying gas to the groove 14a (second boundary groove) which is provided closest to the boundary 102a and extends along the boundary 102a. At least two (second gas introduction holes) can be provided. In addition, in the example shown in FIG. 11, three gas introduction holes 15 are provided.
By doing so, similarly to the above-described one, it is possible to suppress the influence of the variation in the hole diameters of the gas introduction holes 15 and to more reliably supply the gas to the groove 14a extending along the boundary 102a.

Next, the effect of the groove 14c will be further described.
FIG. 12A is a schematic plan view for illustrating the arrangement of the grooves 14 according to the comparative example.
In FIG. 12A, a plurality of grooves 14 are provided on the surface of the substrate 110. The plurality of grooves 14 have an annular shape and are concentrically provided at equal intervals centering on the center 110a of the substrate 110. Note that the groove 14c is not provided in FIG.
FIG. 12B is a schematic plan view for illustrating the arrangement of the groove 14 and the groove 14c.
In FIG. 12B, a plurality of grooves 14 and a plurality of grooves 14c for communicating at least a part of the plurality of grooves 14 are provided. In this example, the groove 14c is 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.

FIG. 13 is a graph for illustrating the pressure change at the center 110a of the substrate 110. FIG. 13 is a graph showing a pressure change at the center 110a of the substrate 110 obtained by simulation. In the simulation, it is assumed that the object W supported by the dots 13 is above the substrate 110.
E in FIG. 13 is a case where the plurality of grooves 14 illustrated in FIG. 12A are provided.
F in FIG. 13 indicates a case where the plurality of grooves 14 and the plurality of grooves 14c illustrated in FIG. 12B are provided.

As can be seen from FIG. 13, in the case of the example illustrated in FIG. 12A (case of E), the pressure could only be increased to 95% of the predetermined pressure (20 Torr). This means that a pressure distribution can occur in the area.
In the case of the case illustrated in FIG. 12B (case of F), it was possible to raise the pressure to a predetermined pressure (20 Torr). This means that the pressure distribution can be suppressed from occurring in the region.
In the case of F, the time T1 required to raise the pressure to the predetermined pressure was shorter than the time T2 required to raise 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 a predetermined pressure can be significantly shortened, in other words, the responsiveness of gas control and thus temperature control can be improved.

As described above, the gas introduction hole 15 is preferably connected to at least one of the two grooves 14a provided with the boundaries 101a to 103a interposed therebetween.

For example, as illustrated in FIG. 11, in the regions 101, 102, and 104 inside the first main surface 11a, the gas introduction hole 15 may be connected to the groove 14a provided on the outermost side in each region. it can. In the outermost region 103 of the first main surface 11a, the gas introduction hole 15 can be connected to the groove 14a provided on the innermost side.

The number and arrangement of the gas introduction holes 15 provided in each region can be appropriately changed according to the size of the object W, the required specifications of the temperature distribution in the object W, and the like. For example, as illustrated in FIG. 11, three gas introduction holes 15 can be provided in one region at equal intervals. In this case, at least one of the plurality of gas introduction holes 15 provided in the region 103 and the gas introduction hole 15 provided in the region 102 are provided on a line passing through the center of the first main surface 11a. can do.

The above is the case where the region where the gas pressure changes near the boundary is made small. However, considering that the gas is supplied to the grooves 14a and 14c provided in the region, the gas introduction hole 15 has the groove 14a. It is preferable to provide it at a position where the groove 14c intersects with the groove 14c or in the vicinity thereof. For example, when projected onto a plane perpendicular to the Z direction, at least a part of the gas introduction hole 15 is made to overlap with at least one of the groove 14a and the groove 14c in the portion where the groove 14a and the groove 14c are connected. be able to. In this way, it becomes easy for the gas supplied to the groove 14a to flow out to the groove 14c side. Therefore, it is easy to obtain the effect of the groove 14c described above.

14A to 14C are schematic diagrams for illustrating the form of the groove 14c.
FIG. 14B is an enlarged view of the E portion in FIG.
FIG. 14C is an enlarged view of the F portion in FIG.
As shown in FIG. 14B, the groove 14c can be provided so as to overlap with a line drawn from the center of the ceramic dielectric substrate 11 toward the outer periphery, for example. In this case, the angle formed by the tangent line of the groove 14a and the groove 14c can be 90° in the portion where the groove 14a and the groove 14c are connected.
Further, as shown in FIG. 14C, the groove 14c may not overlap with a line drawn from the center of the ceramic dielectric substrate 11 toward the outer periphery, for example. In this case, the angle formed by the tangent line of the groove 14a and the groove 14c at the portion where the groove 14a and the groove 14c are connected is not 90°.

FIG. 15 is a schematic plan view of a ceramic dielectric substrate 11 according to another embodiment.
In the case illustrated in FIG. 11, the first main surface 11a is concentrically divided into a plurality of regions 101 to 104. On the other hand, in the case illustrated in FIG. 15, the first main surface 11a is divided into a plurality of regions 105 that are in close contact with each other. The plurality of regions 105 can be provided side by side. The outer shapes of the plurality of regions 105 are not particularly limited, but it is preferable that the plurality of regions 105 have a shape capable of being in close contact with each other. The plurality of regions 105 can be, for example, a polygon such as a triangle or a quadrangle. The outer shape of the region 105 illustrated in FIG. 15 is a regular hexagon. The outer shape, the number, the arrangement, etc. of the plurality of regions 105 can be appropriately changed according to the size of the object W, the required specifications of the temperature distribution in the object W, and the like. The outer shape, number, arrangement, etc. of the plurality of regions 105 can be appropriately determined by, for example, performing an experiment or a simulation.

The groove 14a is provided along the boundary 105a of the region 105. The groove 14a is provided on both sides of 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 required specifications of the temperature distribution in the object W, and the like. The number and position of the grooves 14b provided in one region can be appropriately determined by, for example, performing an experiment or a simulation.

Other than the above, the groove 14c, the gas introduction hole 15, the dot 13, the lift pin hole 16, the outer seal 17, and the like can be provided.

(Processing device)
FIG. 16 is a schematic diagram for illustrating the processing device 200 according to the present embodiment.
As shown in FIG. 16, the processing apparatus 200 can be provided with the electrostatic chuck 1, the power supply 210, the medium supply unit 220, and the supply unit 230.
The power supply 210 is electrically connected to the electrode 12 provided on the electrostatic chuck 1. The power supply 210 can be, for example, a DC power supply. The power supply 210 applies a predetermined voltage to the electrode 12. Further, the power supply 210 can be provided with a switch for switching between application of voltage and stop of application of voltage.

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 serving as a cooling medium or a heat retention medium.
The medium supply unit 220 has, for example, a storage unit 221, a control valve 222, and a discharge unit 223.

The storage portion 221 can be, for example, a tank for storing a liquid or a factory pipe. Further, the storage section 221 can be provided with a cooling device and a heating device for controlling the temperature of the liquid. The storage part 221 may be provided with a pump or the like for sending out the liquid.

The control valve 222 is connected between the input path 51 and the storage section 221. The control valve 222 can control at least one of the flow rate and the pressure of the liquid. Further, the control valve 222 can switch between supply of liquid and stop of supply.

The discharging unit 223 is connected to the output path 52. The discharge unit 223 can be a tank or a drain pipe that collects the liquid discharged from the output path 52. The discharge part 223 is not always necessary, and the liquid discharged from the output path 52 may be supplied to the storage part 221. By doing so, the cooling medium or the heat retaining medium can be circulated, so that resource saving can be achieved.

The supply unit 230 has a gas supply unit 231 and a gas control unit 232.
The gas supply unit 231 can be a high-pressure cylinder containing a gas such as helium or a factory pipe. Although the case where one gas supply unit 231 is provided has been illustrated, a plurality of gas supply units 231 may be provided.

The gas control unit 232 is connected between the 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 gas. In addition, the gas control unit 232 may further have a function of switching between gas supply and gas supply stop. The gas control unit 232 can be, for example, a mass flow controller or a mass flow meter.

As shown in FIG. 16, a plurality of gas control units 232 can be provided. For example, the gas control unit 232 can be provided for each of the plurality of regions 101 to 104. By doing so, the control of the supplied gas can be performed for each of the plurality of regions 101 to 104. In this case, the gas control unit 232 can be provided for each of the plurality of gas supply passages 53. By doing so, it is possible to more precisely control the gas in the plurality of regions 101 to 104. Although the case where a plurality of gas control units 232 are provided has been illustrated, one gas control unit 232 may be provided as long as the gas control units 232 can independently control the gas supply in the plurality of supply systems.

Here, the means for holding the object W includes a vacuum chuck and a mechanical chuck. However, the vacuum chuck cannot be used in an environment depressurized below atmospheric pressure. Further, when the mechanical chuck is used, the object W may be damaged or particles may be generated. Therefore, for example, an electrostatic chuck is used in a processing apparatus used in a semiconductor manufacturing process or the like.

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 the chamber 240. The chamber 240 can have, for example, an airtight structure capable of maintaining an atmosphere that is depressurized below atmospheric pressure.
In addition, the processing device 200 may include a plurality of lift pins and a drive device that raises and lowers the plurality of lift pins. When the target object W is received from the transfer device or when the target object W is transferred to the transfer device, the lift pins are lifted by the drive device and protrude from the first main surface 11a. When the object W received from the transfer device is placed on the first main surface 11a, the lift pins are lowered by the driving device and are housed inside the ceramic dielectric substrate 11.

Further, the processing device 200 can be provided with various devices according to the content of the processing. For example, a vacuum pump or the like that exhausts the inside of the chamber 240 can be provided. A plasma generator that generates plasma may be provided inside the chamber 240. A process gas supply unit that supplies a process gas may be provided inside the chamber 240. A heater that heats the object W or the process gas may be provided inside the chamber 240. The devices provided in the processing device 200 are not limited to those illustrated. Since a known technique can be applied to the device provided in the processing device 200, detailed description thereof will be omitted.

As described above, the processing apparatus 200 according to the present embodiment includes the electrostatic chuck 1 described above, the first gas introduction hole (gas introduction hole 15) and the second gas introduction hole provided in the electrostatic chuck 1. And a gas control section (gas control section 232) capable of independently controlling the gas supplied to the hole (gas introduction hole 15). With the processing apparatus 200 according to this embodiment, the gas pressure in each region can be made appropriate.

The embodiments of the present invention have been described above. However, the present invention is not limited to these descriptions. For example, as the electrostatic chuck 1, the configuration using the Coulomb force is illustrated, but the configuration using the Johnson-Rahbek force may be used. In addition, those skilled in the art may appropriately modify the above-described embodiments and the present invention is also included in the scope of the present invention as long as the characteristics of the present invention are provided. Further, each element included in each of the above-described embodiments can be combined as long as technically possible, and a combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

DESCRIPTION OF SYMBOLS 1 electrostatic chuck, 11 ceramic dielectric substrate, 11a 1st main surface, 11b 2nd main surface, 12 electrode, 13 dot, 14a-14c groove, 15 gas introduction hole, 16 lift pin hole, 17 outer seal, 50 base plate, 51 input passage, 52 output passage, 53 gas supply passage, 70 second porous portion, 90 first porous portion, 101-104 region, 101a-103a boundary, 200 processing device, 231 gas supply portion, 232 gas control portion , W object

Claims (9)

Base plate,
A ceramic dielectric substrate provided on the base plate and having a first main surface exposed to the outside;
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,
A first boundary groove provided closest to a first boundary between the first region and the second region and extending along the first boundary;
At least one first in-region groove different from the first boundary groove,
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 includes a second boundary groove that is provided closest to the first boundary and extends along the first boundary;
The boundary groove occupancy in a first range having a predetermined unit area and including the first boundary, the first boundary groove, and the second boundary groove includes the first area groove, An electrostatic chuck having a larger area occupation ratio in a second range having the same shape and the same size as the first range. The electrostatic capacitance according to claim 1, wherein a distance between groove ends between the first boundary groove and the second boundary groove is smaller than a distance between groove ends between the first region inner grooves. Chuck. The at least part of the first gas introduction hole overlaps with the first boundary groove when projected onto a plane perpendicular to the first direction from the base plate toward the ceramic dielectric substrate. Or the electrostatic chuck according to 2. The at least part of the second gas introduction hole overlaps with the second boundary groove when projected onto a plane perpendicular to the first direction from the base plate toward the ceramic dielectric substrate. The electrostatic chuck according to any one of 3 to 3. 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 the first boundary is less than 90°. 1. The electrostatic chuck according to one. An angle between a line connecting the center of the first gas introduction hole and the center of the second gas introduction hole and the first boundary is 90°, and the angle is 90°. The electrostatic chuck described in 1. Further comprising a lift pin hole provided on the first main surface,
The distance between the lift pin hole and the first boundary groove is larger than the distance between the lift pin hole and the first region inner groove closest to the lift pin hole. 6. The electrostatic chuck according to any one of 6. The first main surface includes at least the first region, the second region located outside the first region, and the third region located outside the second region and adjacent to the second region. Including,
The plurality of second grooves are provided closest to a second boundary between the second region and the third region, and include a second outer boundary groove extending along the second boundary,
A third boundary groove provided adjacent to the second boundary and extending along the second boundary in the third region;
The boundary groove occupancy in the third range having the predetermined unit area and including the second boundary, the second boundary groove, and the third boundary groove is the area groove occupancy in the first range. The electrostatic chuck according to claim 1, wherein the electrostatic chuck is larger than the ratio. An outer seal provided so as to surround the periphery of the first main surface, at least a part of which is capable of contacting an object to be adsorbed,
In a second direction orthogonal to the first direction from the base plate to the ceramic dielectric substrate,
The electrostatic chuck according to claim 8, wherein a distance between the second boundary and the outer seal is smaller than a distance between the first boundary and the second boundary.

Images