JP2023183458A - holding device - Google Patents

Abstract

To provide a holding device that reduces occurrence of abnormal discharge and easily controls the flow rate of gas.SOLUTION: A holding device includes an insulating plate-like member 10 having a first surface 10A for holding a target object and a second surface 10B located on the opposite side to the first surface 10A, a gas flow path 50 formed inside the plate-like member 10, and an insulating porous portion 60 arranged in the gas flow path 50. The gas flow path 50 has a vertical gas flow path 53 which has an opening on a second surface 10B, and extends in a direction intersecting the first surface 10A, a horizontal gas flow path 54 which communicates with the vertical gas flow path 53 and extends in parallel to the first surface 10A, and a gas outflow hole 51 that communicates with the horizontal gas flow path 54 and has an opening on the first surface 10A. The porous portion 60 includes a first porous portion 61 connected to the horizontal gas flow path 54 in a direction parallel to the first surface 10A, and the first porous portion 61 has a concave portion 63 concaved inwards beyond the outer edge of the first porous portion 61 with respect to the direction parallel to the first surface 10A, and is connected to the horizontal gas flow path 54 at the concave portion 63.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to a retention device.

As an example of a holding device, an electrostatic chuck used in plasma processing for manufacturing semiconductors is known. When performing plasma processing on substrates, wafers, etc., an insulating electrostatic chuck holding the object to be processed on the top surface is placed inside a chamber (processing container), and a conductive electrostatic chuck placed below the electrostatic chuck High frequency power is applied to the cooling base member to generate a bias voltage on the wafer or the like. Inside the electrostatic chuck, there is a gas flow path that communicates the lower surface (the surface on the cooling base member side) and the upper surface (wafer holding surface), and through this gas flow path, the temperature of the wafer holding surface can be controlled. A thermally conductive gas such as helium for increasing the temperature is sent from the cooling base member side to the wafer mounting surface side.

If abnormal discharge (arcing) occurs in the gas flow path due to the high-frequency power applied during plasma processing, the processing quality of wafers, etc. will deteriorate and the yield will decrease.This reduces the occurrence of abnormal discharge without interfering with the gas supply. Technology to do this is required. Therefore, for example, in Patent Document 1 listed below, a plug chamber is formed in a part of the pore that becomes the gas flow path, and a porous and insulating breathable plug made of epoxy resin or the like is placed inside the plug chamber. An electrostatic chuck is disclosed that is adhesively fixed to the wall surface of a plug chamber with an adhesive.

Patent No. 6621548

Incidentally, in recent years, in order to speed up processing, the voltage of high-frequency power applied during plasma processing has been increased. As a result, the potential difference between the cooling base member and the wafer etc. becomes large, and abnormal discharge is likely to occur in the gas flow path, especially in the space extending in the vertical direction. Therefore, the insulating porous body for reducing abnormal discharge is preferably formed so that no gap is created between the porous body and the wall surface of the gas flow path.

To reduce the gap between the porous body and the wall of the gas flow path, for example, an electrostatic chuck can be manufactured by injecting a paste-like raw material for the porous body into a gas flow path that has been prepared in advance and firing it. It is possible to do so. However, when injecting a paste-like porous material raw material into a gas flow path, it may be difficult to control the volume of the porous material to a constant value. Therefore, it may be difficult to equalize the flow rate of gas flowing out from the gas outlet hole through the porous body of the electrostatic chuck.

The present disclosure was completed based on the above circumstances, and an object of the present disclosure is to provide a holding device that can reduce the occurrence of abnormal discharge and easily control the flow rate of gas.

The holding device of the present disclosure includes an insulating plate-like member having a first surface for holding an object and a second surface located on the opposite side of the first surface, and a second surface formed inside the plate-like member. and an insulating porous portion disposed in the gas flow path, the gas flow path having an opening on the second surface and a direction intersecting the first surface. a vertical gas flow path that extends in the vertical gas flow path, a horizontal gas flow path that communicates with the vertical gas flow path and extends parallel to the first surface, and a gas outlet that communicates with the horizontal gas flow path and has an opening on the first surface. pores, the porous portion includes a first porous portion connected to the horizontal gas flow path in a direction parallel to the first surface, and the first porous portion is parallel to the first surface. The holding device has a recess that is recessed inward from an outer edge of the first porous portion in a direction such that the holding device is connected to the horizontal gas flow path at the recess.

According to the present disclosure, it is possible to provide a holding device that can reduce the occurrence of abnormal discharge and easily control the flow rate of gas.

FIG. 1 is a perspective view schematically showing the external configuration of an electrostatic chuck according to a first embodiment. FIG. 2 is a schematic cross-sectional view of the electrostatic chuck. FIG. 3 is a schematic cross-sectional view of the plate-like member showing the periphery of the porous portion in an enlarged manner. FIG. 4 is a schematic plan view of the plate-like member showing an enlarged view of the periphery of the porous portion. FIG. 5 is a perspective view of the porous portion. FIG. 6 is a schematic cross-sectional view of a plate-like member showing a porous portion that also serves as a gas outflow hole. FIG. 7 is an explanatory diagram schematically showing a method for manufacturing a plate-like member. FIG. 8 is a schematic cross-sectional view of a plate-like member showing an enlarged view of the periphery of a porous portion according to the second embodiment. FIG. 9 is a schematic cross-sectional view of a plate-like member showing an enlarged view of the periphery of a porous portion and other porous portions according to the third embodiment. FIG. 10 is a diagram schematically showing a gas flow path in a plan view. FIG. 11 is a schematic cross-sectional view of a plate-like member showing a porous section without a second porous section according to another embodiment. FIG. 12 is a schematic cross-sectional view of a plate-like member showing a recess that is inserted inside a through-hole of an electrode member according to another embodiment. FIG. 13 is a diagram schematically showing two bypass channels according to another embodiment. FIG. 14 is a diagram schematically showing a bypass flow path having a connection flow path according to another embodiment.

[Description of embodiments of the present disclosure]
First, embodiments of the present disclosure will be listed and described.
(1) The holding device of the present disclosure includes an insulating plate-like member having a first surface for holding an object and a second surface located on the opposite side of the first surface; It has a gas flow path formed inside and an insulating porous part arranged in the gas flow path, and the gas flow path has an opening on the second surface and an opening on the first surface. a vertical gas flow path extending in intersecting directions, communicating with the vertical gas flow path, a horizontal gas flow path extending parallel to the first surface, communicating with the horizontal gas flow path, and having an opening in the first surface; a gas outflow hole, the porous portion includes a first porous portion connected to the horizontal gas flow path in a direction parallel to the first surface, and the first porous portion The holding device has a recess that is recessed inward from the outer edge of the first porous portion in a direction parallel to the surface, and is connected to the horizontal gas flow path at the recess.

The first porous portion of the porous portion is provided with a concave portion recessed in a direction parallel to the first surface, and the first porous portion and the horizontal gas flow path are connected in this recess, so that the horizontal gas flow path is reliably connected. Gas can be passed through the porous portion. Further, by controlling the shape and size of the recessed portion, the volume of the porous portion can be controlled. Therefore, it is easy to control the flow rate of gas flowing out from the gas outlet hole.

(2) The holding device according to (1) further includes an electrode member disposed inside the plate member and having a through hole penetrating in a direction perpendicular to the first surface, the electrode member , arranged on the first surface side in a direction perpendicular to the first surface, and the horizontal gas flow path is arranged inside the through hole of the electrode member when viewed from the direction perpendicular to the first surface. Preferably not.

Since the lateral gas flow path is not disposed inside the through hole of the electrode member when viewed from the direction perpendicular to the first surface, abnormal discharge in the lateral gas flow path can be suppressed.

(3) In the holding device according to (2), the porous portion is arranged closer to the first surface than the first porous portion, and is connected to the gas outflow hole in a direction intersecting the first surface. Preferably, the electrode member further includes a second porous portion, and the second porous portion is disposed within the through hole of the electrode member.

By arranging the second porous portion of the porous portion within the through hole of the electrode member, it is possible to reduce the cavity in the direction orthogonal to the first surface between the opening of the first surface and the porous portion. , abnormal discharge can be suppressed.

(4) In the holding device according to (3), when viewed from a direction perpendicular to the first surface, the second porous portion is arranged inside the first porous portion in a direction parallel to the first surface. It is preferable that the

Since the second porous portion is arranged inside the first porous portion when viewed from the direction perpendicular to the first surface, the size of the second porous portion in the direction parallel to the first surface can be reduced. Therefore, the diameter of the through-hole of the electrode member can be reduced, and the area of the electrode member can be increased. Therefore, abnormal discharge can be suppressed while maintaining the function of the electrode member.

(5) In the holding device according to (1), (2), (3) or (4), the holding device is arranged in a gas flow path at a position different from the porous portion in a direction parallel to the first surface. The horizontal gas passage further includes a first gas passage connected to the porous part in the recess, and a second gas passage connecting the porous part and the other porous part. It is preferable to have a bypass flow path that directly connects the first gas flow path and the second gas flow path.

The holding device includes a porous portion and another porous portion, and the horizontal gas flow path has a first gas flow path connected to the porous portion and a second gas flow path connected to the porous portion and the other porous portion. , gas flows from the porous portion to the gas outflow hole, so that the gas pressure in the second gas flow path becomes lower than the gas pressure in the first gas flow path. In the above configuration, by providing a bypass flow path that directly connects the first gas flow path and the second gas flow path, gas can be supplied to the porous portion and other porous portions without gas pressure loss. . Therefore, the flow rate of gas flowing out from the gas outflow holes connected to each of the porous portion and other porous portions can be made constant.

(6) In the holding device according to (1), (2), (3), (4) or (5), the recess has an opening on an end surface of the first porous portion on the first surface side. However, it is preferable that the opening is opened in a direction perpendicular to the first surface.

According to such a configuration, the recess can be enlarged in the direction perpendicular to the first surface, so the flow rate of gas can be increased.

(7) In the holding device according to (1), (2), (3), (4) or (5), the recessed portion is closer to the first surface than the end surface of the first porous portion. It is preferable that it be arranged on the second surface side.

According to such a configuration, it is easy to ensure the volume of the porous portion above the recess, and therefore it is easy to suppress abnormal discharge.

[Details of Embodiment 1 of the present disclosure]
Embodiment 1 of the present disclosure will be described with reference to FIGS. 1 to 7. Note that the present disclosure is not limited to these examples, but is indicated by the scope of the claims, and is intended to include all changes within the meaning and scope equivalent to the scope of the claims. In the following description, with respect to a plurality of identical members, only some of the members may be labeled with reference numerals, and the reference numerals of other members may be omitted.

<Electrostatic chuck>
The holding device of the present disclosure is an electrostatic chuck 100 that can attract and hold an object (hereinafter referred to as "wafer W") such as a semiconductor wafer or a glass substrate. The electrostatic chuck 100 is attached to, for example, a processing chamber of a semiconductor manufacturing apparatus (not shown), and is used to perform various processes (film formation, etching, etc.) on a wafer W using plasma.

As shown in FIG. 1, the electrostatic chuck 100 includes a plate member 10 and a base member 20. The plate member 10 and the base member 20 are joined by a joint 30. The joint portion 30 is made of, for example, an adhesive such as silicone resin, acrylic resin, or epoxy resin. The electrostatic chuck 100 is capable of attracting and holding the wafer W by electrostatic attraction.

The base member 20 is a disc-shaped member, and can be formed into a shape having a diameter of about 340 mm and a thickness of about 35 mm, for example. The base member 20 is mainly composed of a conductive material such as aluminum or aluminum alloy. In addition, the main component here means the component with the largest content ratio (weight ratio). As shown in FIG. 2, the base member 20 has a third surface 20A disposed on the plate-like member 10 side and a fourth surface 20B disposed on the opposite side to the third surface 20A. The third surface 20A is arranged on the upper side of the base member 20, and the fourth surface 20B is arranged on the lower side of the base member 20. The third surface 20A of the base member 20 is joined to the second surface 10B of the plate-like member 10, which will be described later, by a joint 30.

A refrigerant flow path 21 is provided inside the base member 20 . The refrigerant flow path 21 is connected to a refrigerant circulation device (not shown). The refrigerant circulation device is configured to be able to circulate a refrigerant such as a fluorine-based inert liquid or water through the refrigerant channel 21 . When the refrigerant flows through the refrigerant flow path 21, the base member 20 is cooled, and the plate-like member 10 is cooled by heat transfer (heat removal) between the base member 20 and the plate-like member 10 via the joint 30. The wafer W held on the first surface 10A of the plate member 10, which will be described later, is cooled. Thereby, the temperature of the wafer W can be controlled.

Furthermore, a gas injection path 22 is provided inside the base member 20 so that a fluid can move therethrough. The gas injection path 22 is open to the fourth surface 20B of the base member 20, and communicates with a gas flow path 50 of the plate-shaped member 10, which will be described later, through a hole in the joint portion 30. A thermally conductive gas is injected from the gas injection path 22 into the gas flow path 50.

<Plate member>
The plate member 10 has a disk shape as a whole, and can be formed into a shape having a diameter of about 300 mm and a thickness of about 5 mm, for example. The plate-like member 10 is an insulating substrate, and is made of, for example, ceramics whose main component is aluminum nitride (AlN) or alumina (Al ₂ O ₃ ). The plate-like member 10 has a first surface 10A that holds the wafer W, and a second surface 10B disposed on the opposite side of the first surface 10A. As shown in FIG. 2, the first surface 10A is arranged on the upper side of the plate-like member 10, and the second surface 10B is arranged on the lower side of the plate-like member 10. The second surface 10B is joined to the base member 20 via the joint 30.

<Electrode member>
A chuck electrode 40 (an example of an electrode member) is disposed inside the plate member 10 at a position on the first surface 10A side (upper side). The chuck electrode 40 has, for example, a planar shape substantially parallel to the first surface 10A, and is connected to a power source via a terminal or the like. Electrostatic attraction is generated by supplying power to chuck electrode 40 as needed, and wafer W is attracted and held on first surface 10A. The chuck electrode 40 can be formed of a conductive material containing, for example, tungsten or molybdenum. The chuck electrode 40 is formed with a through hole 41 that penetrates the chuck electrode 40 in the vertical direction. The electrode member is not limited to a chuck electrode, but may also be a high frequency electrode or a heater electrode.

<Gas flow path>
As shown in FIG. 1, a plurality of gas outflow holes 51 are provided on the first surface 10A of the plate member 10. As shown in FIG. 2, gas inflow holes 52 are provided on the second surface 10B. A gas passage 50 is formed inside the plate member 10 to allow fluid to move between the gas outflow hole 51 and the gas inflow hole 52. A thermally conductive gas such as helium gas is flowed through the gas flow path 50 of the plate member 10 . Gas injected into the gas inflow hole 52 from the gas injection path 22 of the base member 20 passes through the gas flow path 50 and flows out from the gas outflow hole 51.

As shown in FIG. 3, the gas flow path 50 has a gas inflow hole 52, and communicates with the vertical gas flow path 53 extending in a direction intersecting the first surface 10A. It has a horizontal gas flow path 54 extending parallel to 10A. The horizontal gas passage 54 and the gas outlet hole 51 communicate with each other via a porous portion 60, which will be described later.

<Porous part>
A porous portion 60 is embedded inside the plate member 10 . The porous portion 60 is a porous member made of an insulating material such as ceramics, and is formed so that a fluid can flow therethrough. The porous portion 60 is arranged within the gas flow path 50. Specifically, the porous portion 60 communicates with the horizontal gas flow path 54 and with the gas outlet hole 51 .

The porous portion 60 includes a first porous portion 61 and a second porous portion 62 provided continuously above the first porous portion 61 . In this embodiment, the second porous portion 62 is located inside the first porous portion 61 in a direction parallel to the first surface 10A (horizontal direction) when viewed from the direction perpendicular to the first surface 10A (vertical direction). It is arranged. The first porous portion 61 and the second porous portion 62 can be formed into a substantially cylindrical shape, as shown in FIG. The first porous portion 61 and the second porous portion 62 do not have to be substantially cylindrical, and may be, for example, substantially polygonal.

As shown in FIG. 3, the first porous portion 61 is formed with a recessed portion 63 that is recessed inward from the outer edge of the first porous portion 61 in the horizontal direction. The first porous portion 61 communicates with the horizontal gas flow path 54 at the recessed portion 63 . The inner space of the recess 63 is included in the horizontal gas flow path 54. In this embodiment, the recess 63 is arranged below (on the second surface 10B side) the end surface 61A of the first porous portion 61 on the first surface 10A side (upper side). Thereby, the volume of the first porous portion 61 disposed above the horizontal gas flow path 54 can be secured, and abnormal discharge within the gas flow path 50 can be suppressed.

In this embodiment, as shown in FIG. 4, the horizontal gas flow path 54 is not arranged within the through hole 41 of the chuck electrode 40 when viewed from the top and bottom. In other words, when viewed from the top and bottom, the horizontal gas flow path 54 is arranged so as to overlap the chuck electrode 40 (shaded portion in FIG. 4) except for the through hole 41. With this arrangement, abnormal discharge in the horizontal gas flow path 54 can be suppressed.

As shown in FIG. 3, the second porous portion 62 extends in the vertical direction and is disposed inside the through hole 41 of the chuck electrode 40. As shown in FIG. By providing the second porous portion 62, the number of gas channels 50 extending in the vertical direction connected to the gas outflow holes 51 can be reduced, and abnormal discharge in the gas channels 50 can be suppressed.

As shown in FIG. 6, the second porous portion 62 is provided within the gas flow path 50 up to the first surface 10A of the plate-like member 10, and the second porous portion 62 is provided within the gas flow path 50 extending in the vertical direction on the first surface 10A side. You can bury it. That is, the second porous portion 62 may also serve as the gas outflow hole 51.

<About the manufacturing method of electrostatic chuck>
The above is the configuration of the electrostatic chuck 100 of this embodiment, and below, an example of a method for manufacturing the plate member 10 and the electrostatic chuck 100 will be described with reference to FIG. The method for manufacturing the plate member 10 is an application of a sheet lamination method using green sheets (ceramic green sheets). Note that in FIG. 7, the lower side of the drawing corresponds to the first surface 10A side of the plate-like member 10, and the upper side of the drawing corresponds to the second surface 10B side of the plate-like member 10.

First, as shown in FIG. 7(A), a plurality of green sheets 2 that will become the basis of the plate-shaped member 10 are laminated. Note that a conductive paste is printed at necessary locations on the green sheet 2, and a conductor layer 2A is formed by laminating a plurality of green sheets 2. The conductor layer 2A corresponds to electrodes such as the chuck electrode 40 of the plate member 10 and the wiring pattern.

As shown in FIG. 7(B), the stacked green sheets 2 are cut with a router or the like to form the porous portion accommodating portion 3.

As shown in FIG. 7C, a paste-like precursor 4 of the porous portion 60 is poured into the porous portion accommodating portion 3, and the green sheet 2 and the precursor 4 are dried.

As shown in FIG. 7(D), a portion of the dried green sheet 2 and precursor 4 is shaved to form a first hole 5 extending in the horizontal direction. The first hole 5 corresponds to the recess 63 of the plate member 10 and the horizontal gas flow path 54. By cutting the precursor 4 to form the first hole 5, the recess 63 can be provided. Thereby, gas can be reliably circulated from the horizontal gas flow path 54 to the porous portion 60. Furthermore, by forming the recess 63 through the above steps, the shape and size of the recess 63 can be easily controlled. Therefore, the volume of the porous portion 60 can be controlled, and the flow rate of gas can be easily controlled.

As shown in FIG. 7(E), green sheets 2 are further laminated from the state shown in FIG. 7(D) to form second holes 6 extending in the vertical direction. The second hole portion 6 corresponds to the vertical gas flow path 53 of the plate member 10.

As shown in FIG. 7(F), the green sheet 2 is shaved to form a third hole 7. Note that at this time, a portion of the precursor 4 of the porous portion 60 may be shaved off. The third hole 7 corresponds to the gas outflow hole 51 of the plate member 10. Further, the formation of the third hole portion 7 may be performed in the step of forming the porous portion accommodating portion 3 shown in FIG. Precursor 4 of section 60 may enter.

The green sheet laminate 8 obtained in the step shown in FIG. 7(F) is fired (degreasing firing). The fired body is formed into a precise shape by polishing, and a metal pin that conducts electricity is joined to this shape by brazing. The plate-shaped member 10 is obtained through the above steps.

The plate member 10 described above is joined to a base member 20 obtained by a known method via a joint 30 (see FIG. 1). With the above steps, manufacturing of the electrostatic chuck 100 is completed. Note that the method for manufacturing the plate-like member 10 of the present disclosure is not limited to the above, and various known methods can be adopted as appropriate.

<Effects of Embodiment 1>
As described above, the holding device (electrostatic chuck 100) of the first embodiment has a first surface 10A that holds the object (wafer W), a second surface 10B located on the opposite side of the first surface 10A, an insulating plate-like member 10 having a gas flow path; a gas flow path 50 formed inside the plate-like member 10; and an insulating porous portion 60 disposed in the gas flow path 50. 50 has an opening on the second surface 10B and extends in a direction intersecting the first surface 10A, and a horizontal gas flow that communicates with the vertical gas flow path 53 and extends parallel to the first surface 10A. and a gas outflow hole 51 that communicates with the horizontal gas flow path 54 and has an opening on the first surface 10A, and the porous portion 60 connects the horizontal gas flow path 54 in a direction parallel to the first surface 10A. The first porous part 61 has a concave part 63 that is recessed inward from the outer edge of the first porous part 61 in a direction parallel to the first surface 10A, and the concave part 63 has a concave part 63 that is recessed in the direction parallel to the first surface 10A. It is connected to the flow path 54.

The first porous portion 61 of the porous portion 60 is provided with a recess 63 recessed in a direction parallel to the first surface 10A, and the first porous portion 61 and the horizontal gas flow path 54 are connected in this recess 63. , the gas can reliably flow from the horizontal gas flow path 54 to the porous portion 60. Further, by controlling the shape and size of the recess 63, the volume of the porous portion 60 can be controlled. Therefore, it is easy to control the flow rate of gas flowing out from the gas outflow hole 51.

The holding device of Embodiment 1 further includes an electrode member (chuck electrode 40) disposed inside the plate member 10 and having a through hole 41 penetrating in a direction perpendicular to the first surface 10A. , is arranged on the first surface 10A side in the direction perpendicular to the first surface 10A, and the horizontal gas flow path 54 is not arranged inside the through hole 41 of the electrode member when viewed from the direction perpendicular to the first surface 10A. .

Since the horizontal gas flow path 54 is not disposed inside the through hole 41 of the electrode member when viewed from the direction perpendicular to the first surface 10A, abnormal discharge in the horizontal gas flow path 54 can be suppressed.

In the first embodiment, the porous portion 60 is arranged closer to the first surface 10A than the first porous portion 61, and further includes a second porous portion 62 connected to the gas outlet hole 51 in a direction crossing the first surface 10A. The second porous portion 62 is disposed within the through hole 41 of the electrode member.

Since the second porous portion 62 of the porous portion 60 is disposed within the through hole 41 of the electrode member, a cavity in the direction perpendicular to the first surface 10A between the opening of the first surface 10A and the porous portion 60 is formed. can be made small, and abnormal discharge can be suppressed.

In the first embodiment, the second porous portion 62 is arranged inside the first porous portion 61 in a direction parallel to the first surface 10A when viewed from a direction perpendicular to the first surface 10A.

Since the second porous portion 62 is arranged inside the first porous portion 61 when viewed from the direction perpendicular to the first surface 10A, the size of the second porous portion 62 in the direction parallel to the first surface 10A is reduced. can do. Therefore, the diameter of the through hole 41 of the electrode member can be reduced, and the area of the electrode member can be increased. Therefore, abnormal discharge can be suppressed while maintaining the function of the electrode member.

In the first embodiment, the recessed portion 63 is arranged closer to the second surface 10B than the end surface 61A of the first porous portion 61 on the first surface 10A side.

According to such a configuration, it is easy to ensure the volume of the porous portion 60 above the recessed portion 63, and therefore it is easy to suppress abnormal discharge.

[Details of Embodiment 2 of the present disclosure]
Embodiment 2 of the present disclosure will be described with reference to FIG. 8. The electrostatic chuck 200 of the second embodiment includes a plate-like member 110, a base member 20, and a joint portion 30. The plate member 110 differs from the plate member 10 of the first embodiment in the shapes of the recess 163 and the horizontal gas flow path 154. The other configurations of the second embodiment are the same as those of the first embodiment, so the same members as those of the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

Inside the plate member 110, a porous portion 160 is arranged within the gas flow path 150. The porous portion 160 includes a first porous portion 161 and a second porous portion 62. The first porous portion 161 has a recess 163 and is connected to the horizontal gas flow path 154 at the recess 163 .

The recess 163 of the second embodiment has an opening 163A in an end surface 161A on the first surface 10A side (upper side) of the first porous portion 161. The opening 163A passes through the end surface 161A of the first porous portion 161 in the vertical direction. The horizontal gas flow path 154 is formed above the opening 163A, and is larger in the vertical direction than the horizontal gas flow path 54 of the first embodiment.

<Effects of Embodiment 2>
In the second embodiment, the recess 163 has an opening 163A on the end surface 161A of the first porous portion 161 on the first surface 10A side, and the opening 163A opens in a direction perpendicular to the first surface 10A.

According to such a configuration, since the recess 163 can be made larger in the direction orthogonal to the first surface 10A, the flow rate of gas can be increased.

[Details of Embodiment 3 of the present disclosure]
Embodiment 3 of the present disclosure will be described with reference to FIGS. 9 and 10. The electrostatic chuck 300 of Embodiment 3 includes a plate member 210, a base member 20, and a joint portion 30. The plate member 210 differs from the plate member 10 of the first embodiment in the shape of the horizontal gas flow path 254. The other configurations of the second embodiment are the same as those of the first embodiment, so the same members as those of the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 9, in the gas flow path 250 of the plate member 210, there are porous portions 60 similar to those in FIG. 6 of the first embodiment, and the porous portions 60 are located at different positions in the direction parallel to the first surface 10A. Another porous portion 260 is arranged. In this embodiment, it is assumed that the other porous portions 260 are configured similarly to the porous portion 60 and are connected to the horizontal gas flow path 254 at the recessed portions 63.

The horizontal gas flow path 254 of Embodiment 3 has a first gas flow path 254A connected to the porous portion 60 and a second gas flow path 254B connected to the porous portion 60 and other porous portions 260. . The porous portion 60 is connected to the first gas flow path 254A and the second gas flow path 254B at the recess 63. The first gas flow path 254A is connected to the vertical gas flow path 53. The other porous portion 260 is connected to the second gas flow path 254B at the recessed portion 63.

FIG. 10 is a diagram showing the positional relationship of the gas flow path 250, the porous portion 60, and the other porous portions 260 when viewed from above. In FIG. 10, electrode members and the like are omitted, and the outline of the gas flow path 250 is schematically shown. As shown in FIG. 10, the horizontal gas flow path 254 further includes a bypass flow path 255 that directly connects the first gas flow path 254A and the second gas flow path 254B.

Unlike this embodiment, when the bypass flow path 255 is not provided, when gas flows from the first gas flow path 254A directly connected to the vertical gas flow path 53 to the second gas flow path 254B, As the gas flows out from the gas outlet hole 51 connected to the porous portion 60, a gas pressure loss occurs, so that the gas pressure in the second gas flow path 254B becomes lower than the gas pressure in the first gas flow path 254A. . Therefore, the flow rate of gas flowing out from the other porous portions 260 to the gas outlet hole 51 becomes smaller than the flow rate of gas flowing out from the porous portion 60 to the gas outlet hole 51.

On the other hand, in this embodiment, the first gas flow path 254A and the second gas flow path 254B are directly connected by the bypass flow path 255 without using the porous portion 60. Therefore, the gas pressure becomes equal in the first gas flow path 254A and the second gas flow path 254B. Therefore, the flow rate of gas from the porous portion 60 and the flow rate of gas from the other porous portions 260 can be made the same.

<Effects of Embodiment 3>
The holding device (electrostatic chuck 300) of Embodiment 3 further includes another porous section 260 disposed in the gas flow path 250 at a different position from the porous section 60 in the direction parallel to the first surface 10A, The horizontal gas flow path 254 includes a first gas flow path 254A connected to the porous portion 60 in the recess 63, a second gas flow path 254B connecting the porous portion 60 to another porous portion 260, and a first gas flow path 254A connected to the porous portion 60 in the recess 63. It has a bypass passage 255 that directly connects the passage 254A and the second gas passage 254B.

The holding device includes a porous portion 60 and another porous portion 260, and the horizontal gas flow path 254 is connected to the first gas flow path 254A connected to the porous portion 60, and the porous portion 60 and the other porous portion 260. When the second gas flow path 254B is provided, the gas flows from the porous portion 60 to the gas outlet hole 51, so that the gas pressure in the second gas flow path 254B is lower than the gas pressure in the first gas flow path 254A. turn into. In the above configuration, by providing the bypass flow path 255 that directly connects the first gas flow path 254A and the second gas flow path 254B, gas can be supplied to the porous portion 60 and the other porous portions 260 without gas pressure loss. can be supplied. Therefore, the flow rate of gas flowing out from the gas outflow holes 51 connected to each of the porous portions 60 and other porous portions 260 can be made constant.

<Other embodiments>
(1) In Embodiment 1, the porous portion 60 was provided with the second porous portion 62, but as shown in FIG. 11, the second porous portion may be omitted.

(2) In Embodiment 1, the horizontal gas flow path 54 was not arranged inside the through hole 41 of the electrode member when viewed from the vertical direction, but as shown in FIG. The lateral gas flow path 54 (and recess 63) may be formed so as to penetrate into the lateral gas flow path 54 (and recess 63).

(3) In the third embodiment, the porous portion 60 was connected to the second gas flow path 254B at the recess 63, but the porous portion does not need to be connected to the second gas flow path at the recess.

(4) In the third embodiment, the first gas flow path 254A was directly connected to the vertical gas flow path 53, but the vertical gas flow path may be connected to any part of the horizontal gas flow path; The first gas flow path may not be directly connected to the vertical gas flow path.

(5) In the third embodiment, the other porous portion 260 was connected to the horizontal gas flow path 254 at the recess 63, but the other porous portion may be connected to the horizontal gas flow path without using the recess. good.

(6) In the third embodiment, one bypass flow path 255 is provided, but a plurality of bypass flow paths may be provided. For example, as shown in FIG. 13, two bypass channels 255 may be provided.

(7) As shown in FIG. 14, the bypass flow path 255 may have a connection flow path 256 connected to the porous portion 60.

2...Green sheet 2A...Conductor layer 3...Porous part accommodating part 4...Precursor 5...1st hole part 6...2nd hole part 7...3rd hole part 8...green sheet laminate 10, 110, 210... plate shape Member 10A...First surface 10B...Second surface 20...Base member 20A...Third surface 20B...Fourth surface 21...Refrigerant channel 22...Gas injection path 30...Joint portion 40...Chuck electrode 41...Through hole 50,150 , 250... Gas flow path 51... Gas outflow hole 52... Gas inflow hole 53... Vertical gas flow path 54, 154, 254... Horizontal gas flow path 254A... First gas flow path 254B... Second gas flow path 255... Bypass flow Channel 256... Connection channel 60, 160... Porous section 61, 161... First porous section 61A, 161A... End surface on the first surface side 62... Second porous section 63, 163... Recessed section 163A... Opening 260... Other porous section 100, 200, 300...Electrostatic chuck W...Wafer

Claims (7)

an insulating plate-like member having a first surface that holds an object and a second surface located on the opposite side of the first surface; a gas flow path formed inside the plate-like member; an insulating porous portion disposed in the gas flow path,
The gas flow path is
a vertical gas flow path having an opening on the second surface and extending in a direction intersecting the first surface;
a horizontal gas flow path communicating with the vertical gas flow path and extending parallel to the first surface;
a gas outflow hole communicating with the horizontal gas flow path and having an opening on the first surface;
The porous portion includes a first porous portion connected to the horizontal gas flow path in a direction parallel to the first surface,
The first porous portion has a recessed portion recessed inward from an outer edge of the first porous portion in a direction parallel to the first surface, and is connected to the horizontal gas flow path at the recessed portion. further comprising an electrode member disposed inside the plate member and having a through hole penetrating in a direction perpendicular to the first surface;
The electrode member is arranged on the first surface side in a direction perpendicular to the first surface,
The holding device according to claim 1, wherein the horizontal gas flow path is not arranged inside the through hole of the electrode member when viewed from a direction perpendicular to the first surface. The porous portion further includes a second porous portion disposed closer to the first surface than the first porous portion and connected to the gas outflow hole in a direction intersecting the first surface,
The holding device according to claim 2, wherein the second porous portion is disposed within the through hole of the electrode member. The holding device according to claim 3, wherein the second porous portion is arranged inside the first porous portion in a direction parallel to the first surface when viewed from a direction perpendicular to the first surface. further comprising another porous portion located in a gas flow path at a different position from the porous portion in a direction parallel to the first surface,
The horizontal gas flow path includes a first gas flow path connected to the porous portion in the recess, a second gas flow path connecting the porous portion and the other porous portion, and the first gas flow path. The holding device according to any one of claims 1 to 4, further comprising a bypass flow path that directly connects the first gas flow path and the second gas flow path. The recessed portion has an opening on an end surface of the first porous portion on the first surface side,
The holding device according to any one of claims 1 to 4, wherein the opening is opened in a direction perpendicular to the first surface. The holding device according to any one of claims 1 to 4, wherein the recessed portion is arranged closer to the second surface than an end surface of the first porous portion on the first surface side.

Images