JP7283872B2 - holding device - Google Patents

Description

The technology disclosed in this specification relates to a holding device that holds an object.

For example, an electrostatic chuck is used as a holding device for holding a wafer within a vacuum chamber of a semiconductor manufacturing apparatus. An electrostatic chuck comprises a ceramic plate-shaped member having a surface (hereinafter referred to as "attraction surface") substantially orthogonal to a predetermined direction (hereinafter referred to as "first direction") and a metal base, for example. It includes a member, a joint portion that joins the plate-like member and the base member, and a chuck electrode provided inside the plate-like member. The wafer is held by suction on the suction surface of the plate-shaped member.

If the temperature of the wafer held on the attraction surface of the electrostatic chuck does not reach the desired temperature, the precision of each process (film formation, etching, etc.) on the wafer may decrease. The ability to control the distribution is required. Therefore, for example, the temperature distribution of the adsorption surface of the plate-shaped member is changed by heating by a heater electrode arranged inside the plate-shaped member or by cooling by supplying a coolant to a coolant channel formed inside the base member. Control (and control of the temperature distribution of the wafer held on the suction surface) is performed.

In addition, in order to improve the heat transfer between the plate-like member and the wafer and further improve the controllability of the temperature distribution of the wafer, an inert gas such as helium is filled in the space between the adsorption surface of the plate-like member and the surface of the wafer. is known (see, for example, Patent Document 1). In this holding device, a gas supply channel connected to a gas source is formed inside the base member, a gas ejection channel opening to the adsorption surface is formed inside the plate-like member, and the joining portion includes the above-mentioned A through hole is formed to communicate the gas supply channel and the gas ejection channel. The inert gas supplied from the gas source to the gas supply channel of the base member flows into the gas ejection channel of the plate-shaped member through the through-hole formed in the joint portion, and flows into the plate-shaped member in the gas ejection channel. is supplied to the space between the attraction surface and the surface of the wafer from an opening (jet port) to the attraction surface.

In the holding device having the structure for supplying the inert gas as described above, the surface of the plate-like member facing the base member is provided with a concave portion communicating with the gas ejection flow path. In addition, in order to suppress the occurrence of electric discharge between the plate-like member and the base member via the inside of the concave portion and discharge of inert gas, the concave portion is formed of an insulating material and has a porosity higher than that of the plate-like member. A porous portion having a high V is arranged. The inert gas supplied to the gas supply channel of the base member passes through the internal holes of the porous portion arranged in the recess and flows into the gas ejection channel of the plate member.

JP 2013-232641 A

As described above, since the porosity of the porous portion is higher than the porosity of the plate-like member, heat transfer from the plate-like member to the base member ( The rate of heat extraction is reduced. Therefore, in the configuration of the conventional holding device, there is a problem that the responsiveness of temperature distribution control is low in the vicinity of the region of the attraction surface of the plate-like member that overlaps the porous portion when viewed in the first direction.

In addition, such a problem is not limited to the form in which the recess in which the porous portion is arranged is formed on the surface of the plate-like member facing the base member, and the recess is not limited to the plate-like member of the base member. Problems common to the form formed on the surface of the opposing side, and the form formed on both the surface of the plate-like member facing the base member and the surface of the base member facing the plate-like member is. Further, such a problem is not limited to electrostatic chucks that hold wafers using electrostatic attraction, but also holding devices that include a plate-like member and a base member and hold an object on the surface of the plate-like member. This is a common problem in general.

This specification discloses a technology capable of solving the above-described problems.

The technology disclosed in this specification can be implemented, for example, in the following forms.

(1) The holding device disclosed in this specification is made of ceramics and has a first surface substantially orthogonal to a first direction and a second surface opposite to the first surface. a plate-like member in which a gas ejection passage opening to the first surface is formed; a heater electrode disposed inside the plate-like member and formed of a resistance heating element; a base member arranged such that the third surface is located on the second surface side of the plate-shaped member, and a coolant channel and a gas supply channel are formed therein; A joining portion disposed between the second surface of the member and the third surface of the base member to join the plate-like member and the base member, the joining portion being formed in the plate-like member. a joint section having a through-hole communicating with the gas ejection channel and the gas supply channel formed in the base member, wherein an object is placed on the first surface of the plate member In the holding device, at least one of the second surface of the plate-like member and the third surface of the base member is formed with a concave portion communicating with the gas ejection channel or the gas supply channel. A porous portion made of a first insulating material and having a porosity higher than that of the plate-like member is arranged in the concave portion, and a part of the internal hole in the porous portion has A filler formed of a second insulating material and connected to the junction is filled. In this holding device, a part of the internal holes in the porous portion is filled with a filler made of an insulating material. Also, the filler is connected to the junction. Therefore, in the portion of the porous portion where the filler is present, the speed of heat transfer (heat removal) in the path from the plate-like member to the base member via the porous portion and the joint portion can be improved. Therefore, according to this holding device, it is possible to suppress a decrease in responsiveness of temperature distribution control on the first surface of the plate member.

(2) In the holding device described above, the second insulating material may be the same as the material forming the joint portion. In this holding device, since the second insulating material, which is the material for forming the filler, is the same as the material for forming the joint, the bondability between the filler and the joint can be improved. Therefore, according to the present holding device, in the portion of the porous portion where the filler is present, the speed of heat transfer (heat removal) in the path from the plate-like member to the base member via the porous portion and the joint portion can be effectively improved, and a decrease in responsiveness of temperature distribution control on the first surface of the plate member can be effectively suppressed.

(3) In the above holding device, the second insulating material may include a resin material and a ceramic material having a higher thermal conductivity than the resin material. In this holding device, since the second insulating material, which is the material for forming the filler, contains a ceramic material having a higher thermal conductivity than the resin material, the thermal conductivity of the filler can be improved. Therefore, according to the present holding device, in the portion of the porous portion where the filler is present, the speed of heat transfer (heat removal) in the path from the plate-like member to the base member via the porous portion and the joint portion can be further effectively improved, and the decrease in responsiveness of temperature distribution control on the first surface of the plate member can be more effectively suppressed.

(4) In the above holding device, the recess is formed on the second surface of the plate-like member, and the filling material is disposed in the base member relative to the heater electrode in the first direction. may be located only on the side close to . When the filler exists on the side closer to the first surface of the plate member than the heater electrode, the heat generated from the heater electrode is confined around the filler, and the heat is generated in the first direction on the first surface of the plate member. There is a risk that the vicinity of the region that visually overlaps with the filler will become a high temperature singular point. However, in this holding device, since the filler does not exist on the side closer to the first surface than the heater electrode in the first direction, it is possible to avoid the occurrence of a high-temperature singular point on the first surface of the plate member. can be suppressed.

It should be noted that the technology disclosed in this specification can be implemented in various forms, for example, in the form of a holding device, an electrostatic chuck, a vacuum chuck, a heater device, a manufacturing method thereof, and the like. is possible.

1 is a perspective view schematically showing an external configuration of an electrostatic chuck 100 according to this embodiment; FIG. It is an explanatory view showing roughly the XZ section composition of electrostatic chuck 100 in this embodiment. It is an explanatory view showing roughly the XY plane (upper surface) composition of electrostatic chuck 100 in this embodiment. It is an explanatory view showing roughly the XY section composition of electrostatic zipper 100 in this embodiment. It is explanatory drawing which expands and shows the XZ cross-sectional structure of the X1 part of FIG. It is explanatory drawing which expands and shows the XZ cross-sectional structure of the electrostatic chuck 100 of a modification.

A. Embodiment:
A-1. Configuration of electrostatic chuck 100:
FIG. 1 is a perspective view schematically showing the external configuration of an electrostatic chuck 100 according to the present embodiment, and FIG. 2 is an explanatory view schematically showing the XZ cross-sectional configuration of the electrostatic chuck 100 according to the present embodiment. 3 is an explanatory view schematically showing the XY plane (upper surface) configuration of the electrostatic chuck 100 in this embodiment, and FIG. 4 schematically shows the XY cross-sectional configuration of the electrostatic chuck 100 in this embodiment. It is an explanatory diagram showing. FIG. 4 shows the XY cross-sectional configuration of the electrostatic chuck 100 at the position IV-IV in FIG. Each figure shows mutually orthogonal XYZ axes for specifying directions. In this specification, for the sake of convenience, the positive direction of the Z-axis is referred to as the upward direction, and the negative direction of the Z-axis is referred to as the downward direction. may be Moreover, below, the direction orthogonal to Z-axis direction is called "surface direction." The Z-axis direction corresponds to the first direction in the claims.

The electrostatic chuck 100 is a device that attracts and holds an object (for example, a wafer W) by electrostatic attraction, and is used, for example, to fix the wafer W within a vacuum chamber of a semiconductor manufacturing apparatus. The electrostatic chuck 100 includes a plate-like member 10 and a base member 20 arranged side by side in a predetermined arrangement direction (vertical direction (Z-axis direction) in this embodiment). The plate-like member 10 and the base member 20 are arranged so that the lower surface S2 (see FIG. 2) of the plate-like member 10 and the upper surface S3 of the base member 20 face each other in the arrangement direction with a joint portion 30 to be described later interposed therebetween. be done. That is, the base member 20 is arranged such that the upper surface S3 of the base member 20 is located on the lower surface S2 side of the plate-shaped member 10 . The lower surface S2 of the plate member 10 corresponds to the second surface in the claims, and the upper surface S3 of the base member 20 corresponds to the third surface in the claims.

The plate-like member 10 is a substantially disc-like member and is made of ceramics (for example, alumina, aluminum nitride, or the like). More specifically, the plate-like member 10 is composed of an outer peripheral portion OP, which is a portion having a notch formed on the upper side along the outer periphery, and an inner portion IP located inside the outer peripheral portion OP. The thickness of the inner portion IP of the plate member 10 (thickness in the Z-axis direction, the same applies hereinafter) is greater than the thickness of the outer peripheral portion OP by the notch formed in the outer peripheral portion OP. That is, the thickness of the plate-like member 10 changes at the position of the boundary between the outer peripheral portion OP and the inner portion IP of the plate-like member 10 .

The diameter of the inner portion IP of the plate member 10 is, for example, about 50 mm to 500 mm (usually about 200 mm to 350 mm), and the diameter of the outer peripheral portion OP of the plate member 10 is, for example, about 60 mm to 510 mm (usually, about 210 mm to 360 mm). ) (where the diameter of the outer peripheral portion OP is larger than the diameter of the inner portion IP). Further, the thickness of the inner portion IP of the plate-like member 10 is, for example, about 1 mm to 10 mm, and the thickness of the outer peripheral portion OP of the plate-like member 10 is, for example, about 0.5 mm to 9.5 mm (however, the outer peripheral portion The thickness of OP is less than the thickness of inner part IP).

Among the upper surfaces S1 of the plate-shaped member 10, the upper surface (hereinafter also referred to as "attraction surface") S11 at the inner portion IP is a substantially circular surface substantially orthogonal to the Z-axis direction. The attraction surface S11 functions as an attraction surface that holds an object (for example, a wafer W). The attraction surface S11 corresponds to the first surface in the claims.

As shown in FIGS. 2 and 3, a continuous wall-shaped projection (hereinafter referred to as a “wall-shaped projection”) 12 is formed near the outer edge of the attraction surface S11 of the plate-shaped member 10 . . The wall-shaped protrusion 12 is also called a seal band. As shown in FIG. 3, the shape of the wall-shaped convex portion 12 as viewed in the Z-axis direction is a substantially annular shape centered on the center P0 of the attraction surface S11 of the plate-shaped member 10. As shown in FIG. Further, as shown in FIG. 2, the shape of the cross section of the wall-shaped protrusion 12 (the cross section parallel to the Z-axis and passing through the center P0) is substantially rectangular. The height of the wall-like protrusions 12 is, for example, about 10 μm to 20 μm. Further, the width of the wall-like protrusions 12 (the size in the direction perpendicular to the extending direction of the wall-like protrusions 12 as viewed in the Z-axis direction) is, for example, about 0.5 mm to 5.0 mm.

A plurality of independent columnar protrusions (hereinafter referred to as “columnar protrusions”) 14 are formed in a region inside the wall-like protrusions 12 on the attracting surface S11 of the plate-like member 10 . As shown in FIG. 3, the shape of each columnar protrusion 14 as viewed in the Z-axis direction is substantially circular. In addition, as viewed in the Z-axis direction, the plurality of columnar protrusions 14 are arranged at approximately equal intervals. Moreover, as shown in FIG. 2, the shape of the cross section (the cross section parallel to the Z-axis) of each columnar protrusion 14 is substantially rectangular. The height of the columnar protrusions 14 is substantially the same as the height of the protrusions 12, and is, for example, about 10 μm to 20 μm. Further, the width of the columnar protrusion 14 (maximum diameter of the columnar protrusion 14 as viewed in the Z-axis direction) is, for example, about 0.5 mm to 1.5 mm. In addition, in the area inside the wall-shaped protrusion 12 on the attraction surface S11 of the plate-shaped member 10, the portion where the column-shaped protrusion 14 is not formed serves as a recess 16. As shown in FIG.

The wafer W is supported by the wall-shaped protrusions 12 and the plurality of columnar protrusions 14 on the suction surface S11 of the plate-shaped member 10 . In a state in which the wafer W is supported by the wall-shaped projections 12 and the plurality of columnar projections 14, the surface (lower surface) of the wafer W and the suction surface S11 of the plate member 10 (more specifically, the recesses 16 of the suction surface S11). ), there will be a space between As will be described later, this space is supplied with an inert gas (eg, helium gas).

Among the upper surfaces S1 of the plate-shaped member 10, an upper surface S12 in the outer peripheral portion OP (hereinafter also referred to as "peripheral upper surface") is a substantially annular surface that is substantially orthogonal to the Z-axis direction. A jig (not shown) for fixing the electrostatic chuck 100 , for example, is engaged with the outer peripheral upper surface S<b>12 of the plate member 10 .

As shown in FIG. 2, a chuck electrode 40 made of a conductive material (eg, tungsten, molybdenum, platinum, etc.) is arranged inside the plate member 10 . The chuck electrode 40 is a plate-like member extending substantially parallel to the surface direction. The shape of the chuck electrode 40 as viewed in the Z-axis direction is, for example, a substantially circular shape. When a voltage is applied to the chuck electrode 40 from a power source (not shown), electrostatic attraction is generated, and the wafer W is attracted and fixed to the attraction surface S11 of the plate member 10 by this electrostatic attraction.

A heater electrode 50 made of a resistance heating element containing a conductive material (eg, tungsten, molybdenum, platinum, etc.) is arranged inside the plate member 10 . The heater electrode 50 is a member having a linear portion extending substantially parallel to the surface direction. The position of the heater electrode 50 in the Z-axis direction is below the position of the chuck electrode 40 . The shape of the heater electrode 50 as viewed in the Z-axis direction is, for example, a substantially spiral shape. When a voltage is applied to the heater electrode 50 from a power source (not shown), the heater electrode 50 generates heat, thereby warming the plate-like member 10 and warming the wafer W held on the suction surface S11 of the plate-like member 10 . . Thereby, control of the temperature distribution of the wafer W is realized.

The base member 20 is, for example, a circular planar plate-like member having the same diameter as the outer peripheral portion OP of the plate-like member 10 or having a larger diameter than the outer peripheral portion OP of the plate-like member 10. For example, metal (aluminum, aluminum alloy, etc.) ). The diameter of the base member 20 is, for example, approximately 220 mm to 550 mm (usually 220 mm to 350 mm), and the thickness of the base member 20 is, for example, approximately 20 mm to 40 mm.

The base member 20 is joined to the plate member 10 by a joining portion 30 arranged between the lower surface S2 of the plate member 10 and the upper surface S3 of the base member 20. As shown in FIG. The joint portion 30 is made of a resin material such as silicone resin, acrylic resin, or epoxy resin. In addition, in the present embodiment, the joint portion 30 contains, as a filler, a ceramic material having a higher thermal conductivity than the resin material. The thickness of the joint portion 30 is, for example, about 0.1 mm to 1 mm.

A coolant channel 21 is formed inside the base member 20 . When a coolant (for example, a fluorine-based inert liquid, water, or the like) is caused to flow through the coolant channel 21 , the base member 20 is cooled, and heat is transferred between the base member 20 and the plate-like member 10 via the joint portion 30 . The plate-like member 10 is cooled by (thermal drawing), and the wafer W held on the adsorption surface S11 of the plate-like member 10 is cooled. Thereby, control of the temperature distribution of the wafer W is realized.

A-2. Configuration for helium gas supply:
The electrostatic chuck 100 of the present embodiment enhances the heat transfer between the plate-like member 10 and the wafer W to further enhance the controllability of the temperature distribution of the wafer W. It has a configuration for supplying an inert gas to the space existing between the surface (lower surface) of the. In addition, in this embodiment, helium gas (He gas) is used as such an inert gas. A configuration for supplying helium gas will be described below. FIG. 5 is an explanatory diagram showing an enlarged XZ cross-sectional configuration of the X1 portion of FIG.

As shown in FIGS. 2 to 5, inside the base member 20, a gas supply channel 22 is formed, which is a gas channel that communicates between the lower surface S4 and the upper surface S3 of the base member 20. As shown in FIG. The number of gas supply channels 22 formed inside the base member 20 can be any number, but in this embodiment, there are two.

A recess 18 is formed in the lower surface S2 of the plate-like member 10 at a position overlapping the gas supply channel 22 of the base member 20 as viewed in the Z-axis direction. The XY cross-sectional shape of the recess 18 is, for example, substantially circular. In this embodiment, the position of the bottom surface 17 of the recess 18 in the Z-axis direction is above the position of the heater electrode 50 .

Further, inside the plate-like member 10, a gas jet flow path 130 is formed as a gas flow path that communicates between the concave portion 18 of the plate-like member 10 and the adsorption surface S11. The gas ejection channel 130 includes a first vertical channel 131 communicating with the bottom surface 17 of the recess 18 and extending upward, a horizontal channel 133 communicating with the first vertical channel 131 and extending in the plane direction, and a horizontal channel. and a second vertical flow path 132 extending upward from 133 to (the concave portion 16 of) the attracting surface S11. The opening of the second vertical flow path 132 to the adsorption surface S11 of the plate member 10 functions as a helium gas ejection port. Although the number of channels constituting the gas ejection channel 130 formed inside the plate member 10 can be any number, in the present embodiment, the first longitudinal channel 131 and the lateral channel 131 are provided. The number of 133 is two (see FIG. 4), and the number of second longitudinal channels 132 is eight (see FIG. 3).

In addition, through-holes 31 are formed in the joint portion 30 to communicate the gas ejection passages 130 formed in the plate member 10 and the gas supply passages 22 formed in the base member 20 . More specifically, the through hole 31 of the joint portion 30 directly communicates with the gas supply channel 22 of the base member 20 and also communicates with the gas ejection channel 130 through the recess 18 of the plate member 10 . It communicates with one longitudinal channel 131 .

As described above, in the electrostatic chuck 100 of the present embodiment, the gas supply channel 22 formed in the base member 20, the through hole 31 formed in the joint portion 30, and the concave portion 18 formed in the plate member 10 and the gas ejection channel 130 communicate with each other to form a channel for supplying helium gas.

Further, as shown in FIGS. 2 and 5, a breathable plug 160 is arranged in the recess 18 formed in the plate member 10. As shown in FIG. The air-permeable plug 160 is, for example, a substantially cylindrical member and made of an insulating material. Also, the porosity of the air-permeable plug 160 is higher than that of the plate member 10 . The diameter of the internal hole in the air-permeable plug 160 is, for example, about 10 μm to 200 μm. As a material for forming the air-permeable plug 160, for example, ceramic porous body, glass fiber, heat-resistant polytetrafluoroethylene resin sponge, or the like can be used. In this embodiment, the vent plug 160 is adhesively secured within the recess 18 . The existence of the gas-permeable plug 160 suppresses the occurrence of electrical discharge between the plate-like member 10 and the base member 20 via the recess 18 and discharge of helium gas within the recess 18 . The gas-permeable plug 160 corresponds to the porous portion in the claims, and the material forming the gas-permeable plug 160 corresponds to the first insulating material.

When helium gas supplied from a helium gas source (not shown) flows into the gas supply channel 22 of the base member 20 , the helium gas that has flowed into the through hole 31 of the joint 30 from the gas supply channel 22 . Then, the gas passes through the internal hole of the gas-permeable plug 160 arranged in the recess 18 of the plate-like member 10 and flows into the first longitudinal channel 131 forming the gas ejection channel 130, and further, While moving in the lateral flow path 133 in the planar direction, it flows into the second vertical flow path 132 and is jetted out from the ejection port that is the opening to the adsorption surface S11 in each second vertical flow path 132 . In this manner, the helium gas is supplied to the space existing between the attraction surface S11 of the plate member 10 and the surface of the wafer W. As shown in FIG.

Here, in the electrostatic chuck 100 of the present embodiment, as shown in FIG. 5, a part of the internal hole of the gas-permeable plug 160 is filled with a filler 162 made of an insulating material. In this embodiment, the material for forming the filler 162 is the same as the material for forming the joint portion 30 . That is, the material forming the filler 162 includes a resin material (eg, silicone resin, acrylic resin, epoxy resin, etc.) and a ceramic material having a higher thermal conductivity than the resin material. The material forming the filler 162 corresponds to the second insulating material in the claims. The filling amount of the filler 162 in the air-permeable plug 160 is preferably about 25 to 50% by volume, for example.

A filling material 162 filled in the internal hole of the air-permeable plug 160 is connected to the joint portion 30 . That is, the filling material 162 is filled so as to be positioned at least on the surface (lower surface) of the air-permeable plug 160 in contact with the joint portion 30 . In the present embodiment, the filler 162 is formed in a shape extending upward from a plurality of locations on the lower surface of the air-permeable plug 160 (locations other than the locations facing the through holes 31 of the joint portion 30). . Further, in this embodiment, the height (the size in the Z-axis direction) of the filler 162 is lower than the position of the heater electrode 50 . That is, in the Z-axis direction, the filling material 162 is positioned only on the side closer to the base member 20 (that is, on the lower side) with respect to the heater electrode 50 .

A-3. Manufacturing method of electrostatic chuck 100:
A method for manufacturing the electrostatic chuck 100 of the present embodiment is, for example, as follows. First, the plate member 10 and the base member 20 are prepared. The plate member 10 and the base member 20 can be manufactured by a known manufacturing method. For example, the plate member 10 is manufactured by the following method. That is, a plurality of ceramic green sheets (for example, alumina green sheets) are prepared, and predetermined ceramic green sheets are subjected to predetermined processing. The predetermined processing includes, for example, printing of metallized paste for forming the chuck electrode 40 and the heater electrode 50, drilling for forming each via and filling with metallized paste, and forming each gas flow path. Examples include perforation and the like. By stacking these ceramic green sheets, thermocompression bonding, and processing such as cutting, a laminate of ceramic green sheets is obtained. The laminate of the obtained ceramic green sheets is fired to produce a ceramic fired body, and then subjected to predetermined processing such as polishing and shot blasting for forming the wall-shaped protrusions 12 and the columnar protrusions 14. Thus, the plate member 10 is manufactured.

Next, the recess 18 is formed in the lower surface S2 of the plate member 10. As shown in FIG. The concave portion 18 is formed by polishing, for example. The recessed portion 18 is formed so as to communicate with the first vertical flow path 131 forming the gas ejection flow path 130 .

Next, the breathable plug 160 is prepared and placed in the recess 18 of the plate member 10 . More specifically, a mixed material of a resin material and a ceramic material is press-fitted from the lower surface of the breathable plug 160 while sucking from the upper surface side of the breathable plug 160, thereby partially filling the internal hole of the breathable plug 160. , fill the filler material 162 formed by the mixed material. In this way, the filling material 162 can be filled so as to be positioned at least on the lower surface of the breathable plug 160 . In addition, the amount and shape (height, etc.) of the filling material 162 in the air-permeable plug 160 can be adjusted by adjusting the suction or press-in pressure and the amount of the mixed material. Next, after applying an adhesive to the surface of the breathable plug 160 and/or the surface of the recess 18 , the breathable plug 160 is inserted into the recess 18 and the adhesive is cured to attach the breathable plug 160 to the recess 18 . fixed to

Next, the plate member 10 and the base member 20 are joined together. More specifically, in a state in which the lower surface S2 of the plate member 10 and the upper surface S3 of the base member 20 are bonded together via a mixed material of a resin material and a ceramic material, a curing process is performed to cure the mixed material. Thereby, a joint portion 30 for joining the plate member 10 and the base member 20 is formed. When the mixed material is placed between the plate-like member 10 and the base member 20, holes corresponding to the through holes 31 are provided, and the joints 30 formed by hardening the mixed material are through holes. 31 is formed. In addition, as described above, since the filler 162 is positioned at least on the lower surface of the air-permeable plug 160 , when the plate-like member 10 and the base member 20 are joined by the joining portion 30 , the filler 162 is connected to the junction 30 . Manufacture of the electrostatic chuck 100 having the configuration described above is completed mainly through the above steps.

A-4. Effect of this embodiment:
As described above, the electrostatic chuck 100 of this embodiment includes the plate member 10, the base member 20, and the joint portion 30. As shown in FIG. The plate member 10 is made of ceramics and has an attraction surface S11 substantially perpendicular to the Z-axis direction and a lower surface S2 opposite to the attraction surface S11. Inside the plate-like member 10, a gas jet flow path 130 is formed that opens to the adsorption surface S11. A heater electrode 50 formed of a resistance heating element is arranged inside the plate member 10 . The base member 20 has an upper surface S3 and is arranged so that the upper surface S3 of the base member 20 is located on the lower surface S2 side of the plate member 10 . A coolant channel 21 and a gas supply channel 22 are formed inside the base member 20 . The joining portion 30 is arranged between the lower surface S2 of the plate member 10 and the upper surface S3 of the base member 20 to join the plate member 10 and the base member 20 together. The joint portion 30 is formed with a through hole 31 that communicates the gas ejection channel 130 formed in the plate member 10 and the gas supply channel 22 formed in the base member 20 . Further, in the electrostatic chuck 100 of the present embodiment, the concave portion 18 is formed in the lower surface S2 of the plate-like member 10 to communicate with the gas ejection flow path 130 . A breathable plug 160 made of an insulating material and having a porosity higher than that of the plate member 10 is arranged in the recess 18 . A part of the internal hole of the air-permeable plug 160 is filled with a filler 162 made of an insulating material and connected to the joint 30 .

Here, since the porosity of the breathable plug 160 is higher than the porosity of the plate-like member 10, at the place where the breathable plug 160 is located, the distance from the plate-like member 10 to the base member 20 is greater than at other places. There is a possibility that the speed of heat transfer (heat extraction) may become low, and as a result, the responsiveness of the temperature distribution control may decrease in the vicinity of the area of the adsorption surface S11 of the plate member 10 that overlaps the air-permeable plug 160 as viewed in the Z-axis direction. is likely to be lower. However, in the electrostatic chuck 100 of the present embodiment, a part of the internal hole of the gas-permeable plug 160 is filled with a filler 162 made of an insulating material. Also, this filler 162 is connected to the joint portion 30 . Therefore, in the portion of the air-permeable plug 160 where the filler 162 exists, the speed of heat transfer (heat removal) in the path from the plate-like member 10 to the base member 20 via the air-permeable plug 160 and the joint portion 30 is reduced. can be improved. Therefore, according to the electrostatic chuck 100 of the present embodiment, it is possible to suppress deterioration in responsiveness of temperature distribution control of the attraction surface S11 of the plate member 10 .

In addition, in the electrostatic chuck 100 of the present embodiment, the material (insulating material) for forming the filler 162 is the same as the material for forming the bonding portion 30 . Therefore, in the electrostatic chuck 100 of this embodiment, the bondability between the filler 162 and the joint portion 30 can be improved. Therefore, according to the electrostatic chuck 100 of the present embodiment, at the portion of the air-permeable plug 160 where the filling material 162 exists, the air-permeable plug 160 and the joint portion 30 pass from the plate-like member 10 to the base member 20 . It is possible to effectively improve the speed of heat transfer (heat extraction) in the path leading to the plate-like member 10, and to effectively suppress the deterioration of the responsiveness of the temperature distribution control of the adsorption surface S11 of the plate member 10. FIG.

In addition, in the electrostatic chuck 100 of the present embodiment, the material (insulating material) forming the filler 162 includes a resin material and a ceramic material having a higher thermal conductivity than the resin material. Therefore, in the electrostatic chuck 100 of this embodiment, the thermal conductivity of the filler 162 can be improved. Therefore, according to the electrostatic chuck 100 of the present embodiment, at the portion of the air-permeable plug 160 where the filling material 162 exists, the air-permeable plug 160 and the joint portion 30 pass from the plate-like member 10 to the base member 20 . It is possible to further effectively improve the speed of heat transfer (heat extraction) in the route leading to the plate-like member 10, and to further effectively suppress the deterioration of the responsiveness of the temperature distribution control of the adsorption surface S11 of the plate-like member 10.

In addition, in the electrostatic chuck 100 of the present embodiment, the filling material 162 is positioned only on the side closer to the base member 20 (lower side) than the heater electrode 50 in the Z-axis direction. Here, if the filler 162 is present on the side (upper side) closer to the attraction surface S11 than the heater electrode 50, the heat generated from the heater electrode 50 is confined around the filler 162, and the attraction surface S11, as viewed in the Z-axis direction. There is a possibility that the vicinity of the region overlapping with the filling material 162 in , becomes a high-temperature temperature singular point. However, in the electrostatic chuck 100 of the present embodiment, the filling material 162 does not exist on the side (upper side) closer to the attraction surface S11 than the heater electrode 50 in the Z-axis direction. It is possible to suppress the occurrence of temperature singularities.

B. Variant:
The technology disclosed in this specification is not limited to the above-described embodiments, and can be modified in various forms without departing from the scope of the invention. For example, the following modifications are possible.

The configuration of the electrostatic chuck 100 in the above embodiment is merely an example, and various modifications are possible. For example, in the above embodiment, the recess 18 in which the breathable plug 160 is arranged is formed in the lower surface S2 of the plate member 10, but the position of the recess in which the breathable plug 160 is arranged is not limited to this. . For example, as in the modification shown in FIG. 6, a recess 28 in which the breathable plug 160 is arranged may be formed in the upper surface S3 of the base member 20. As shown in FIG. In the modification shown in FIG. 6, the gas supply channel 22 is formed inside the base member 20, and the concave portion 28 communicating with the gas supply channel 22 is formed in the upper surface S3 of the base member 20. A gas ejection channel 130 is formed inside the member 10 , and a through hole 31 is formed in the joining portion 30 to communicate the gas ejection channel 130 of the plate member 10 and the gas supply channel 22 of the base member 20 . ing. In addition, in the modification shown in FIG. 6, as in the above embodiment, a part of the internal hole of the breathable plug 160 is filled with a filler 162 made of an insulating material, and the filler 162 is joined. It is connected with the section 30 . Therefore, according to the modification shown in FIG. 6, as in the above-described embodiment, at the portion of the breathable plug 160 where the filling material 162 is present, the plate-like member 10 passes through the joint 30 and the breathable plug 160. Therefore, the speed of heat transfer (heat removal) in the path to the base member 20 can be improved, and a decrease in responsiveness of temperature distribution control of the adsorption surface S11 of the plate-like member 10 can be suppressed. Moreover, recesses in which the breathable plugs 160 are arranged may be formed in both the lower surface S2 of the plate-like member 10 and the upper surface S3 of the base member 20 .

Further, in the above-described embodiment, the breathable plug 160, which is a separate member from the plate-shaped member 10, is arranged in the concave portion 18 of the plate-shaped member 10, but instead of using the breathable plug 160, the plate-shaped member A portion of the plate member 10 may be processed to form a porous portion having a higher porosity than other portions of the plate member 10 .

Further, the shape of the filler 162 filled in the air-permeable plug 160 in the above embodiment is merely an example, and various modifications are possible. For example, in the above embodiment, the filler material 162 is shaped to extend upward from the bottom surface of the breathable plug 160, but the filler material 162 is shaped to extend obliquely upward from the bottom surface of the breathable plug 160. may In addition, it is not always necessary that the filler 162 is positioned only on the side closer to the base member 20 (lower side) than the heater electrode 50 in the Z-axis direction.

In the above-described embodiment, the plate-like member 10 is composed of the outer peripheral portion OP, which is a portion in which a notch is formed on the upper side along the outer periphery, and the inner portion IP located inside the outer peripheral portion OP. However, the plate-like member 10 may have no notch and the thickness of the plate-like member 10 in the Z-axis direction may be uniform throughout. Further, in the above-described embodiment, the configuration (shape, position, etc.) of the wall-shaped projections 12 and the column-shaped projections 14 formed on the attraction surface S11 of the plate-shaped member 10 is merely an example, and various modifications are possible. Also, one of the wall-shaped projections 12 and the columnar projections 14 may not be formed. Further, in the above-described embodiment, a monopolar system in which one chuck electrode 40 is provided inside the plate-like member 10 is adopted. method may be employed.

Further, the materials forming each member in the electrostatic chuck 100 of the above-described embodiment are merely examples, and each member may be formed of another material. For example, in the above embodiment, the material for forming the filler 162 is the same as the material for forming the joint portion 30, and includes a resin material and a ceramic material having a higher thermal conductivity than the resin material. The material forming the filler 162 may not be the same as the material forming the joint 30, and even if the material forming the filler 162 is the same as the material forming the joint 30, the material may be the ceramic material. May not be included.

Moreover, the manufacturing method of the electrostatic chuck 100 in the above embodiment is merely an example, and various modifications are possible. For example, in the above embodiment, the recesses 18 are formed by polishing after manufacturing the plate-like member 10. However, even if the recesses 18 are formed by punching the ceramic green sheet before firing, good.

Further, the present invention is not limited to the electrostatic chuck 100 that holds the wafer W using electrostatic attraction, but includes the plate-like member 10 and the base member 20, and holds an object on the surface of the plate-like member 10. It is also applicable to other holding devices (for example, vacuum chucks, heater devices, etc.).

10: plate member 12: wall-shaped protrusion 14: columnar protrusion 16: recess 17: bottom surface 18: recess 20: base member 21: refrigerant channel 22: gas supply channel 28: recess 30: joint 31: penetration Hole 40: Chuck electrode 50: Heater electrode 100: Electrostatic chuck 130: Gas ejection channel 131: First vertical channel 132: Second vertical channel 133: Horizontal channel 160: Breathable plug 162: Filler IP : inner portion OP: outer peripheral portion P0: center S11: adsorption surface S12: outer peripheral upper surface S1: upper surface S2: lower surface S3: upper surface S4: lower surface W: wafer

Claims (3)

A gas ejection channel formed of ceramics and having a first surface substantially orthogonal to a first direction and a second surface opposite to the first surface, and opening to the first surface. a plate-like member formed inside;
a heater electrode disposed inside the plate member and formed of a resistance heating element;
A base member having a third surface, arranged so that the third surface is located on the second surface side of the plate-like member, and having a coolant channel and a gas supply channel formed therein. and,
A joint portion disposed between the second surface of the plate-like member and the third surface of the base member to join the plate-like member and the base member, wherein the plate-like member a joint portion having a through hole communicating between the formed gas ejection channel and the gas supply channel formed in the base member;
A holding device for holding an object on the first surface of the plate member,
at least one of the second surface of the plate-like member and the third surface of the base member is formed with a concave portion communicating with the gas ejection channel or the gas supply channel;
A porous portion made of a first insulating material and having a higher porosity than the plate-like member is arranged in the recess,
A part of the internal holes in the porous portion is filled with a filler formed of a second insulating material and connected to the joint portion,
The second insulating material is the same as the material forming the joint,
A holding device characterized by: A holding device according to claim 1 , wherein
The second insulating material includes a resin material and a ceramic material having a higher thermal conductivity than the resin material,
A holding device characterized by: A gas ejection channel formed of ceramics and having a first surface substantially orthogonal to a first direction and a second surface opposite to the first surface, and opening to the first surface. a plate-like member formed inside;
a heater electrode disposed inside the plate member and formed of a resistance heating element;
A base member having a third surface, arranged so that the third surface is located on the second surface side of the plate-like member, and having a coolant channel and a gas supply channel formed therein. and,
A joint portion disposed between the second surface of the plate-like member and the third surface of the base member to join the plate-like member and the base member, wherein the plate-like member a joint portion having a through hole communicating between the formed gas ejection channel and the gas supply channel formed in the base member;
A holding device for holding an object on the first surface of the plate member,
at least one of the second surface of the plate-like member and the third surface of the base member is formed with a concave portion communicating with the gas ejection channel or the gas supply channel;
A porous portion made of a first insulating material and having a higher porosity than the plate-like member is arranged in the recess,
A part of the internal holes in the porous portion is filled with a filler formed of a second insulating material and connected to the joint portion,
The recess is formed on the second surface of the plate-like member,
In the first direction, the bottom surface of the recess is located on the side closer to the first surface with respect to the heater electrode, and the filler is on the side closer to the base member with respect to the heater electrode. is located only in
A holding device characterized by:

Images