JP2018101773A - Retainer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress reduction of uniformity of temperature distribution in the fist surface of a ceramic plate of a retainer.SOLUTION: A retainer includes a ceramic plate and a base member, and an object is held on the first surface of the ceramic plate orthogonal to a first surface. A recess is formed in at least one of the second surface of the ceramic plate and the third surface of the base member. The retainer further includes a filling member filling the recess. The filling member has gas permeability, and is formed of an insulation material of low heat conductivity. The filling member has an exposure surface exposed from a recess, a bottom surface facing the bottom face of the recess, having an area smaller than that of the exposure surface, and entirely overlapping the exposure surface, and a lateral face connecting the circumference of the exposure surface and the circumference of the bottom surface. The filling member also has a particular part where the size in a second direction orthogonal to the first direction decreases continuously toward the bottom surface.SELECTED DRAWING: Figure 4

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 when manufacturing a semiconductor. The electrostatic chuck includes a ceramic plate and a base member bonded to each other, and utilizes an electrostatic attractive force generated when a voltage is applied to a chuck electrode disposed inside the ceramic plate, thereby the ceramic plate The wafer is adsorbed and held on the surface (hereinafter referred to as “adsorption surface”).

  If the temperature distribution of the wafer held on the electrostatic chuck becomes non-uniform, the accuracy of each process (film formation, etching, etc.) on the wafer may be reduced. Performance is required. Therefore, when the electrostatic chuck is used, the temperature control of the adsorption surface of the ceramic plate is performed by, for example, heating by the heater electrode or cooling by supplying the refrigerant to the refrigerant flow path.

  Also, in order to increase the heat transfer between the ceramic plate and the wafer to further increase the uniformity of the temperature distribution of the wafer, to supply a gas such as helium to the space between the adsorption surface of the ceramic plate and the surface of the wafer A holding device having the structure is known (see, for example, Patent Document 1). In this holding device, a gas supply flow path connected to a gas source is formed inside the base member, and a gas ejection flow path communicating with the gas supply flow path and opening on the adsorption surface is formed inside the ceramic plate. Is formed. The gas supplied from the gas source to the gas supply flow path of the base member flows into the gas ejection flow path of the ceramic plate from the gas supply flow path, and the adsorption surface from the opening (jet port) opened to the adsorption surface of the ceramic plate. And the space between the wafer surface.

  In the holding device having the above-described configuration for supplying the gas, a concave portion having a bottom surface in which the gas ejection channel is opened is provided on the surface of the ceramic plate facing the base member. The recess may be formed not on the surface of the ceramic plate but on the surface of the base member facing the ceramic plate. In this case, the gas supply channel opens at the bottom surface of the recess. Moreover, a recessed part may be formed in both the surface which opposes the base member in a ceramic board, and the surface which opposes the ceramic board in a base member.

  Further, in the holding device described above, in order to suppress the discharge between the ceramic plate and the base member through the recess and the occurrence of gas discharge, the recess has air permeability and is formed of an insulating material. Filled filling members (also called “breathable plugs”) are filled. The gas supplied to the gas supply flow path of the base member passes through the inside of the filling member filled in the recess and flows into the gas ejection flow path of the ceramic plate.

JP2013-232641A

  Since the filling member filled in the recesses described above has a relatively high porosity, the thermal conductivity of the filling member is lower than the thermal conductivity of a relatively dense ceramic plate or base member. For this reason, in the place where the filling member is provided, the heat transfer property (heat drawing characteristic) from the ceramic plate to the base member is locally reduced, and the uniformity of the temperature distribution on the adsorption surface of the ceramic plate may be reduced.

  Such a problem is not limited to the electrostatic chuck that holds the wafer using electrostatic attraction, and is not limited to the configuration including the heater electrode and the coolant channel, and includes a ceramic plate and a base member, This is a common problem in general for a holding device for holding an object on the surface of a ceramic plate.

  In this specification, the technique which can solve the subject mentioned above is disclosed.

  The technology disclosed in the present specification can be realized as, for example, the following forms.

(1) The holding device disclosed in the present specification includes a planar first surface that is substantially orthogonal to the first direction, and a second surface that is opposite to the first surface. A ceramic plate having a gas ejection passage opening in the first surface formed therein, and a third surface, wherein the third surface faces the second surface of the ceramic plate. And a base member having a gas supply channel formed therein, wherein the second surface of the ceramic plate is a holding device for holding an object on the first surface of the ceramic plate. And at least one of the third surface of the base member is formed with a recess having a bottom surface to which the gas ejection channel or the gas supply channel opens, and the holding device further includes the recess It is a filling member filled in and has air permeability. And an exposed surface that is formed of an insulating material whose thermal conductivity is lower than the thermal conductivity of the ceramic plate and the member in which the recess is formed, and is exposed from the recess, and the bottom surface of the recess A bottom surface opposing surface that is smaller in area than the exposed surface and overlaps the exposed surface as a whole in the first direction, and a side surface that connects a peripheral edge of the exposed surface and a peripheral edge of the bottom surface opposing surface. A filling member having a specific portion that continuously decreases as the size in the second direction perpendicular to the first direction becomes closer to the bottom surface, and the recess and the filling member And an adhesive layer having a thermal conductivity higher than that of the filling member. According to this holding device, the path of heat transfer from the ceramic plate (first surface of the ceramic plate) to the base member is shortened without going through the filling member (that is, through the ceramic plate or the adhesive layer). Therefore, it is possible to suppress a decrease in heat transfer from the ceramic plate to the base member at the place where the filling member is provided, and a decrease in temperature distribution uniformity on the first surface of the ceramic plate due to the presence of the filling member. Can be suppressed.

(2) In the holding device, the thermal conductivity of the adhesive layer is lower than the thermal conductivity of the ceramic plate and the member in which the concave portion is formed, and the concave portion is in the second direction. In the above-described configuration, a configuration may be adopted in which the concave portion specific portion is opposed to the specific portion of the filling member and continuously narrows as the width in the second direction approaches the bottom surface. According to this holding device, the path of heat transfer from the ceramic plate (the first surface of the ceramic plate) to the base member is shortened without passing through the filling member and the adhesive layer (that is, through the ceramic plate). Therefore, it is possible to effectively suppress a decrease in heat transfer from the ceramic plate to the base member at the place where the filling member is provided, and the temperature distribution on the first surface of the ceramic plate due to the presence of the filling member is uniform. Can be effectively suppressed.

(3) In the holding device, the filling member may include only the specific portion. According to this holding device, the path of heat transfer from the ceramic plate (the first surface of the ceramic plate) to the base member without passing through the filling member (that is, through the ceramic plate or the adhesive layer) is extremely short. Therefore, it is possible to extremely effectively suppress a decrease in heat transfer from the ceramic plate to the base member at the place where the filling member is provided, and the temperature distribution on the first surface of the ceramic plate due to the presence of the filling member. It is possible to extremely effectively suppress a decrease in uniformity.

(4) In the above holding device, the thermal conductivity of the adhesive layer is lower than the thermal conductivity of the ceramic plate and the member in which the concave portion is formed, and the concave portion is in the second direction. In the structure of the present invention, the structure may be configured only with a recess specific portion that faces the specific portion of the filling member and continuously decreases as the width in the second direction approaches the bottom surface. Good. According to this holding device, the path of heat transfer from the ceramic plate (first surface of the ceramic plate) to the base member is extremely short without going through the filling member and the adhesive layer (that is, through the ceramic plate). Therefore, it is possible to extremely effectively suppress a decrease in heat transfer from the ceramic plate to the base member at the place where the filling member is provided, and the temperature distribution on the first surface of the ceramic plate due to the presence of the filling member. It is possible to extremely effectively suppress a decrease in uniformity.

(5) The holding device further includes a coating layer that has a thermal conductivity higher than that of the adhesive layer and covers at least a part of the side surface and the bottom surface of the filling member. It is good. According to this holding device, the coating layer having a thermal conductivity higher than the thermal conductivity of the adhesive layer is used to transfer heat from the ceramic plate (first surface of the ceramic plate) to the base member without passing through the filling member. Since at least a part of the path can be configured, the amount of heat transfer via the path is increased, and the decrease in heat transfer from the ceramic plate to the base member at the place where the filling member is provided is effectively suppressed. It is possible to effectively suppress a decrease in uniformity of temperature distribution on the first surface of the ceramic plate due to the presence of the filling member.

  The technology disclosed in the present specification can be realized 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.

It is a perspective view which shows roughly the external appearance structure of the electrostatic chuck 10 in 1st Embodiment. It is explanatory drawing which shows roughly the XZ cross-sectional structure of the electrostatic chuck 10 in 1st Embodiment. It is explanatory drawing which shows roughly the XY cross-sectional structure of the electrostatic chuck 10 in 1st Embodiment. It is explanatory drawing which expands and shows the X1 part of the electrostatic chuck 10 in 1st Embodiment. It is a flowchart which shows the manufacturing method of the electrostatic chuck 10 in this embodiment. It is explanatory drawing which shows roughly the structure of the electrostatic chuck 10X of a comparative example. It is explanatory drawing which shows schematically the structure of the electrostatic chuck 10Y of another comparative example. It is explanatory drawing which shows schematically the structure of the electrostatic chuck 10a of 2nd Embodiment. It is explanatory drawing which shows schematically the structure of the electrostatic chuck 10b of 3rd Embodiment. It is explanatory drawing which shows schematically the structure of the electrostatic chuck 10c of 4th Embodiment. It is explanatory drawing which shows schematically the structure of the electrostatic chuck 10d of 5th Embodiment. It is explanatory drawing which shows schematically the structure of the electrostatic chuck 10e of 6th Embodiment. It is explanatory drawing which shows schematically the structure of the electrostatic chuck 10f of 7th Embodiment.

A. First embodiment:
A-1. Configuration of the electrostatic chuck 10:
FIG. 1 is a perspective view schematically showing an external configuration of the electrostatic chuck 10 in the first embodiment, and FIG. 2 is an explanatory diagram schematically showing an XZ cross-sectional configuration of the electrostatic chuck 10 in the first embodiment. FIG. 3 is an explanatory diagram schematically showing an XY cross-sectional configuration of the electrostatic chuck 10 according to the first embodiment. 2 shows an XZ sectional configuration of the electrostatic chuck 10 at the position II-II in FIG. 3, and FIG. 3 shows an XY sectional configuration of the electrostatic chuck 10 at the position III-III in FIG. It is shown. In each figure, XYZ axes orthogonal to each other for specifying the direction are shown. In this specification, for 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. However, the electrostatic chuck 10 is actually installed in an orientation different from such an orientation. May be.

  The electrostatic chuck 10 is an apparatus that attracts and holds an object (for example, a wafer W) by electrostatic attraction, and is used, for example, to fix the wafer W in a vacuum chamber of a semiconductor manufacturing apparatus. The electrostatic chuck 10 includes a ceramic plate 100 and a base member 200 that are arranged in a predetermined arrangement direction (in this embodiment, the vertical direction (Z-axis direction)). The ceramic plate 100 and the base member 200 are arranged so that the lower surface S2 of the ceramic plate 100 and the upper surface S3 of the base member 200 face each other in the arrangement direction. The lower surface S2 of the ceramic plate 100 corresponds to the second surface in the claims, and the upper surface S3 of the base member 200 corresponds to the third surface in the claims.

  The ceramic plate 100 is, for example, a circular flat plate-like member, and is formed of ceramics (for example, alumina, aluminum nitride, etc.). The diameter of the ceramic plate 100 is, for example, about 50 mm to 500 mm (usually about 200 mm to 350 mm), and the thickness of the ceramic plate 100 is, for example, about 1 mm to 10 mm.

  Inside the ceramic plate 100, a pair of chuck electrodes 400 formed of a conductive material (for example, tungsten or molybdenum) is provided. When a voltage is applied to the pair of chuck electrodes 400 from a power source (not shown), an electrostatic attractive force is generated, and the surface of the wafer W opposite to the lower surface S2 of the ceramic plate 100 (hereinafter, referred to as the electrostatic attracting force). (Referred to as “suction surface S1”). The adsorption surface S1 of the ceramic plate 100 is a planar surface substantially orthogonal to the arrangement direction (Z-axis direction) described above. However, in the present embodiment, a plurality of minute protrusions are formed on the suction surface S1 of the ceramic plate 100, and when the wafer W is suction-fixed to the suction surface S1, the suction surface S1 and the surface of the wafer W are There is a slight space between them. The adsorption surface S1 of the ceramic plate 100 corresponds to the first surface in the claims, and the Z-axis direction corresponds to the first direction in the claims. In the present specification, a direction perpendicular to the Z axis (that is, a direction parallel to the suction surface S1) is referred to as a “plane direction”. The surface direction corresponds to the second direction in the claims.

  The base member 200 is a circular flat plate-like member having the same diameter as the ceramic plate 100 or a larger diameter than the ceramic plate 100, and is formed of, for example, metal (aluminum, aluminum alloy, or the like). The diameter of the base member 200 is, for example, about 220 mm to 550 mm (usually 220 mm to 350 mm), and the thickness of the base member 200 is, for example, about 20 mm to 40 mm.

  A coolant channel 210 is formed inside the base member 200. When a coolant (for example, a fluorine-based inert liquid or water) flows through the coolant channel 210, the base member 200 is cooled, and heat is transferred between the base member 200 and the ceramic plate 100 via the adhesive layer 300. The ceramic plate 100 is cooled, and the wafer W held on the suction surface S1 of the ceramic plate 100 is cooled. Thereby, the temperature control of the wafer W is realized.

  The ceramic plate 100 and the base member 200 are joined to each other by an adhesive layer 300 disposed between the lower surface S2 of the ceramic plate 100 and the upper surface S3 of the base member 200. The adhesive layer 300 is made of an adhesive such as a silicone resin, an acrylic resin, or an epoxy resin. The thickness of the adhesive layer 300 is, for example, about 0.1 mm to 1 mm.

  In addition, the electrostatic chuck 10 increases the heat transfer between the ceramic plate 100 and the wafer W to further increase the uniformity of the temperature distribution of the wafer W, so that the suction surface S1 of the ceramic plate 100 and the surface of the wafer W are It has a configuration for supplying gas to a space existing between them. In this embodiment, helium gas (He gas) is used as such a gas. Hereinafter, a configuration for supplying helium gas will be described with reference to FIGS. 1 to 3 and FIG. 4 showing an enlarged view of a portion X1 in FIG.

  As shown in FIGS. 2 and 4, a gas source connection hole 221 connected to a helium gas source (not shown) is formed in the lower surface S4 of the base member 200, and a gas supply is supplied to the upper surface S3 of the base member 200. A hole 222 is opened. Inside the base member 200, a gas supply channel 220 that connects the gas source connection hole 221 and the gas supply hole 222 is formed.

  As shown in FIGS. 2 and 4, the adhesive layer 300 communicates with a gas supply hole 222 formed in the base member 200 and penetrates the adhesive layer 300 in the thickness direction (vertical direction). 310 is formed.

  As shown in FIGS. 1 and 2, eight gas ejection holes 102 are opened on the adsorption surface S <b> 1 of the ceramic plate 100. Further, in the ceramic plate 100, a gas jet that connects a bottom surface 144 (FIG. 4) of a recess 140, which will be described later, formed in the ceramic plate 100 and a gas jet hole 102 opened in the adsorption surface S 1 of the ceramic plate 100. A flow path 110 is formed. The gas ejection channel 110 includes a first vertical channel 111 (FIGS. 2 to 4) extending upward from the bottom surface 144 of the recess 140, and a cross current that communicates with the first vertical channel 111 and extends annularly in the plane direction. A path 114 (FIGS. 2 and 3) and a second vertical channel 112 (FIG. 2) extending upward from the horizontal channel 114 and communicating with the gas ejection hole 102 are configured.

  In the electrostatic chuck 10 of this embodiment, there are two systems for supplying helium gas. That is, as shown in FIG. 3, two transverse channels 114 are formed inside the ceramic plate 100. As shown in FIGS. 2 and 3, the lateral channel 114 closer to the center of the ceramic plate 100 in the two lateral channels 114 is shown in FIGS. 2 and 4 via the first longitudinal channel 111. Four gas ejection holes 102 that are in communication with the recess 140 and that are close to the center of the ceramic plate 100 among the eight gas ejection holes 102 that open to the adsorption surface S1 via the second vertical flow path 112. Communicate. Further, the lateral flow path 114 far from the center of the ceramic plate 100 in the two lateral flow paths 114 communicates with the recess 140 (not shown) via the first vertical flow path 111, and the second flow path 114 Via the longitudinal flow path 112, the eight gas ejection holes 102 opened to the adsorption surface S1 communicate with the four gas ejection holes 102 far from the center of the ceramic plate 100.

  Further, as shown in FIGS. 2 and 4, the gas supply formed on the base member 200 is provided on the lower surface S <b> 2 of the ceramic plate 100 even if there is some error in the relative position between the ceramic plate 100 and the base member 200. A recess 140 is formed so that the flow path 220 and the gas ejection flow path 110 formed in the ceramic plate 100 communicate with each other reliably. The recess 140 communicates with the through hole 310 formed in the adhesive layer 300. Note that the recess 140 communicates with the through-hole 310 when the recess 140 communicates with the through-hole 310 in the state where there are no other members (for example, a filling member 160 and an adhesive layer 170 described later) in the recess 140. Means that Specifically, the recess 140 is formed so as to overlap with the through hole 310 in the thickness direction of the adhesive layer 300.

  The recess 140 includes a bottom surface 144 that is an inner surface close to the suction surface S1, and a side surface 142 that is an inner surface that connects the periphery of the opening 146 (a hole opening in the lower surface S2) of the recess 140 and the periphery of the bottom surface 144. Have. A gas ejection channel 110 (a first vertical channel 111 constituting the gas ejection channel 110) is opened at the bottom surface 144 of the recess 140. In the ceramic plate 100 of this embodiment, since such a recess 140 is formed, the relative position in the surface direction of the base member 200 with respect to the ceramic plate 100 is such that the gas supply flow path 220 formed in the base member 200 is a recess. If it exists in the range which opposes 140, the communication of the gas supply flow path 220 and the gas ejection flow path 110 will be ensured.

  In the present embodiment, the shape of the concave portion 140 (the internal space of the concave portion 140) is a partial cone (a portion in which the apex side of the cone is missing). That is, both the opening 146 and the bottom surface 144 of the recess 140 are substantially circular, and the bottom surface 144 has a smaller area than the opening 146 and overlaps the opening 146 as a whole when viewed in the Z-axis direction. Moreover, the side surface 142 of the recessed part 140 is the shape of the side surface of the said partial cone. Further, the shape of the XZ cross section (that is, the cross section shown in FIG. 4) of the concave portion 140 passing through the center of the bottom surface 144 is a trapezoid. Since the recess 140 has such a configuration, the recess 140 is composed of only the recess specifying portion SP2 that continuously decreases as the width W2 in the direction orthogonal to the Z-axis (ie, the surface direction) approaches the bottom surface 144. I can say that. The phrase “continuously decreases as the width W2 approaches the bottom surface 144” does not include a form in which the width W2 decreases discretely as the width W2 approaches the bottom surface 144. Here, the form in which the width W2 becomes discretely smaller as it approaches the bottom surface 144 is a side surface 142 in the cross section of the recess 140 shown in FIG. 7 as in the electrostatic chuck 10Y (FIG. 7) of the comparative example described later. Is a step-like shape (that is, a shape in which the line representing the side surface 142 has a portion parallel to the surface direction). “Sequentially decreases as the width W2 becomes closer to the bottom surface 144” means that the line representing the side surface 142 does not have a portion parallel to the surface direction in the cross section of the recess 140 shown in FIG.

  As shown in FIGS. 2 and 4, the recess 140 formed in the ceramic plate 100 is filled with a filling member 160 (also referred to as “breathable plug”) that is made of an insulating material and has air permeability. Yes. Since the filling member 160 has a relatively high porosity, the thermal conductivity of the filling member 160 is lower than that of the relatively dense ceramic plate 100. As a material for forming the filling member 160, for example, a ceramic porous body, glass fiber, heat-resistant polytetrafluoroethylene resin sponge, or the like can be used.

  The filling member 160 is exposed from the opening 146 of the recess 140 (exposed through the opening 146), a bottom surface 164 facing the bottom surface 144 of the recess 140, and the periphery and bottom surface of the exposed surface 166. 164 has a side surface 162 connecting the peripheral edge of 164. In this embodiment, the shape of the filling member 160 is a partial cone (a part of the cone lacking a part on the apex side). That is, both the exposed surface 166 and the bottom surface 164 of the filling member 160 are substantially circular, and the bottom surface 164 has a smaller area than the exposed surface 166 and is entirely exposed to the exposed surface 166 when viewed in the Z-axis direction. Overlap. Further, the side surface 162 of the filling member 160 has a shape of a side surface of the partial cone. Moreover, the shape of the XZ cross section (namely, cross section shown in FIG. 4) of the filling member 160 passing through the center of the bottom surface 164 is a trapezoid. Since the filling member 160 has such a configuration, only the specific portion SP1 that continuously decreases as the size (width) W1 in the direction orthogonal to the Z-axis (that is, the surface direction) approaches the bottom surface facing surface 164. It can be said that it is composed of In the present embodiment, the side surface 162 of the filling member 160 is substantially parallel to the side surface 142 of the recess 140. In addition, “the width W1 becomes continuously smaller as it approaches the bottom surface 164” means that the width W1 decreases discretely as the width W1 approaches the bottom surface 164 as described above. Not included. Here, the form in which the width W1 becomes discretely smaller as it approaches the bottom surface 164 is a cross-section of the filling member 160 shown in FIG. 7 as in a comparative example electrostatic chuck 10Y (FIG. 7) described later. The line representing the side surface 162 is stepped (ie, the line representing the side surface 162 has a portion parallel to the surface direction). “Sequentially decreases as the width W1 approaches the bottom surface 164” means that the line representing the side surface 162 does not have a portion parallel to the surface direction in the cross section of the filling member 160 shown in FIG. means.

  An adhesive layer 170 is disposed between the side surface 142 of the recess 140 and the side surface 162 of the filling member 160, and the filling member 160 is joined to the ceramic plate 100 by the adhesive layer 170. The adhesive layer 170 is made of an adhesive such as a silicone resin, an acrylic resin, or an epoxy resin. The thermal conductivity of the adhesive layer 170 is higher than the thermal conductivity of the filling member 160 and lower than the thermal conductivity of the ceramic plate 100. In the present embodiment, the bottom surface facing surface 164 of the filling member 160 is in contact with the bottom surface 144 of the recess 140, and the adhesive layer 170 is disposed between the bottom surface facing surface 164 of the filling member 160 and the bottom surface 144 of the recess 140. It has not been.

  As described above, the filling member 160 formed of an insulating material is filled in the concave portion 140, and the adhesive layer 170 is disposed between the side surface 142 of the concave portion 140 and the side surface 162 of the filling member 160. Occurrence of discharge between the ceramic plate 100 and the base member 200 and the discharge of helium gas in the recess 140 via the.

  As shown in FIGS. 2 and 4, when helium gas supplied from a not-shown helium gas source flows into the gas supply passage 220 inside the base member 200 from the gas source connection hole 221, The gas flows into the through-hole 310 of the adhesive layer 300 from the gas supply flow path 220 through the gas supply hole 222, and further passes through the inside of the filling member 160 filled in the recess 140 to blow out the gas inside the ceramic plate 100. The gas flows into the first vertical flow path 111 constituting the flow path 110 and is ejected from each gas ejection hole 102 formed in the adsorption surface S1 through the horizontal flow path 114 and the second vertical flow path 112. In this way, helium gas is supplied to the space existing between the suction surface S1 and the surface of the wafer W.

A-2. Method for manufacturing electrostatic chuck 10:
FIG. 5 is a flowchart showing a method for manufacturing the electrostatic chuck 10 according to the first embodiment. First, the ceramic plate 100 and the base member 200 are prepared (S110). The ceramic plate 100 and the base member 200 can be manufactured by a known manufacturing method. For example, the ceramic plate 100 is manufactured by the following method. That is, a plurality of ceramic green sheets (for example, alumina green sheets) are prepared, and each ceramic green sheet is subjected to perforating processing for forming the chuck electrode 400 and each gas flow path, printing of metallized ink, and the like. The ceramic plate 100 is manufactured by laminating a plurality of ceramic green sheets, thermocompression-bonding, cutting into a predetermined disc shape, firing, and finally performing polishing or the like. In the present embodiment, the gas ejection channel 110 (the first vertical channel 111, the horizontal channel 114, and the second vertical channel 112) is formed by performing the drilling process on the ceramic green sheet. The

  Next, a recess 140 is formed on the lower surface S2 of the ceramic plate 100 (S120). The recess 140 is formed by, for example, polishing. The recess 140 is formed so as to communicate with the first vertical flow path 111 constituting the gas ejection flow path 110.

  Next, the filling member 160 is installed in the recess 140 of the ceramic plate 100 (S130). Specifically, an adhesive is applied to the side surface 162 of the filling member 160 formed of an insulating material, and the filling member 160 is inserted into the recess 140. At this time, the filling member 160 is pushed in until the bottom surface facing surface 164 of the filling member 160 contacts the bottom surface 144 of the recess 140. When the insertion of the filling member 160 is completed, an adhesive is disposed between the side surface 162 of the filling member 160 and the side surface 142 of the recess 140, and the space between the bottom surface facing surface 164 of the filling member 160 and the bottom surface 144 of the recess 140. In this state, no adhesive is present. Thereafter, the adhesive is cured to form the adhesive layer 170. As described above, the filling member 160 is installed in the recess 140.

  Next, the ceramic plate 100 and the base member 200 are joined (S140). Specifically, the adhesive layer 300 is formed by performing a curing process for curing the adhesive in a state where the lower surface S2 of the ceramic plate 100 and the upper surface S3 of the base member 200 are bonded to each other via the adhesive. . When the adhesive is disposed between the ceramic plate 100 and the base member 200, a hole corresponding to the above-described through-hole 310 is provided, and the through-hole 310 is formed in the adhesive layer 300 formed by the adhesive curing process. To be. With the above steps, the manufacture of the electrostatic chuck 10 having the above-described configuration is completed.

A-3. Effects of the first embodiment:
As described above, the electrostatic chuck 10 according to the first embodiment has the planar suction surface S1 substantially orthogonal to the Z-axis direction and the lower surface S2 opposite to the suction surface S1, and the suction surface. The gas ejection channel 110 that opens to S1 has a ceramic plate 100 formed therein, and an upper surface S3. The upper surface S3 is disposed so as to face the lower surface S2 of the ceramic plate 100, and the gas supply channel 220 is provided inside. The base member 200 is formed. On the lower surface S2 of the ceramic plate 100, a recess 140 having a bottom surface 144 through which the gas ejection channel 110 opens is formed. The ceramic plate 100 further includes a filling member 160 filled in the recess 140. Filling member 160 is made of an insulating material having air permeability and lower thermal conductivity than that of ceramic plate 100, and has exposed surface 166, bottom surface 164, and side surface 162. . The exposed surface 166 of the filling member 160 is a surface exposed from the recess 140. The bottom surface facing surface 164 of the filling member 160 is a surface facing the bottom surface 144 of the recess 140, has a smaller area than the exposed surface 166, and overlaps the exposed surface 166 as a whole when viewed in the Z-axis direction. The side surface 162 is a surface that connects the peripheral edge of the exposed surface 166 and the peripheral edge of the bottom surface 164. In addition, the filling member 160 is configured by only a specific portion SP1 that continuously decreases as the size W1 in the direction (plane direction) orthogonal to the Z-axis direction approaches the bottom surface 164.

  In addition, the electrostatic chuck 10 of the first embodiment includes an adhesive layer 170 disposed between the side surface 142 of the recess 140 and the side surface 162 of the filling member 160. The thermal conductivity of the adhesive layer 170 is higher than the thermal conductivity of the filling member 160 and lower than the thermal conductivity of the ceramic plate 100. Further, the concave portion 140 faces the specific portion SP1 of the filling member 160 in a direction (surface direction) orthogonal to the Z-axis direction, and the concave portion specification continuously decreases as the width W2 in the surface direction approaches the bottom surface 144. It consists only of part SP2.

  Since the electrostatic chuck 10 according to the first embodiment has the above-described configuration, as described below, the decrease in uniformity of temperature distribution on the suction surface S1 of the ceramic plate 100 due to the presence of the filling member 160 is suppressed. be able to.

  FIG. 6 is an explanatory diagram schematically showing the configuration of the electrostatic chuck 10X of the comparative example. FIG. 6 shows an enlarged configuration of a portion equivalent to the portion (X1 portion) shown in FIG. 4 in the configuration of the electrostatic chuck 10X of the comparative example. The electrostatic chuck 10X of the comparative example shown in FIG. 6 differs from the electrostatic chuck 10 of the first embodiment shown in FIG. 4 in the shapes of the recess 140 and the filling member 160. Specifically, in the electrostatic chuck 10X of the comparative example, the shape of the concave portion 140 (the internal space of the concave portion 140) is substantially cylindrical. That is, the opening 146 and the bottom surface 144 of the recess 140 are substantially circular with the same size. Further, the shape of the XZ cross section (that is, the cross section shown in FIG. 6) of the concave portion 140 passing through the center of the bottom surface 144 is a rectangle. Since the concave portion 140 in the electrostatic chuck 10X of the comparative example has such a configuration, the width (W2) in the surface direction is constant throughout, and the portion (such that the width W2 decreases continuously as the width W2 approaches the bottom surface 144 ( The recessed portion specifying portion SP2) in FIG. 4 does not exist.

  The size of the opening 146 of the recess 140 in the electrostatic chuck 10X of the comparative example is the same as the size of the opening 146 of the recess 140 in the electrostatic chuck 10 of the first embodiment. Therefore, the size of the bottom surface 144 of the recess 140 in the electrostatic chuck 10X of the comparative example is larger than the size of the bottom surface 144 of the recess 140 in the electrostatic chuck 10 of the first embodiment. That is, the concave portion 140 in the electrostatic chuck 10 of the first embodiment is smaller in size of the bottom surface 144 while maintaining the size of the opening 146 than the concave portion 140 in the electrostatic chuck 10X of the comparative example. The side surface 142 is tapered.

  Moreover, in the electrostatic chuck 10X of the comparative example, the shape of the filling member 160 is also substantially cylindrical. That is, the exposed surface 166 and the bottom surface 164 of the filling member 160 are substantially circular with the same size. Further, the shape of the XZ cross section (that is, the cross section shown in FIG. 6) of the filling member 160 passing through the center of the bottom surface 164 is a rectangle. Since the filling member 160 in the electrostatic chuck 10 </ b> X of the comparative example has such a configuration, the size W <b> 1 in the surface direction is constant throughout, and continuously decreases as the size W <b> 1 approaches the bottom surface facing surface 164. There is no such part (specific part SP1 in FIG. 4).

  The size of the exposed surface 166 of the filling member 160 in the electrostatic chuck 10X of the comparative example is the same as the size of the exposed surface 166 of the filling member 160 in the electrostatic chuck 10 of the first embodiment. Therefore, the size of the bottom surface 164 of the filling member 160 in the electrostatic chuck 10X of the comparative example is larger than the size of the bottom surface 164 of the filling member 160 in the electrostatic chuck 10 of the first embodiment. That is, the filling member 160 in the electrostatic chuck 10 of the first embodiment has the size of the bottom surface 164 while maintaining the size of the exposed surface 166 with respect to the filling member 160 in the electrostatic chuck 10X of the comparative example. The shape is such that the side surface 162 is scraped off so that becomes smaller.

  Since the electrostatic chuck 10X of the comparative example shown in FIG. 6 has the above-described configuration, the ceramic plate 100 (the ceramic plate 100) does not pass through the filling member 160 and the adhesive layer 170 (that is, through the ceramic plate 100). The heat transfer path HR from the adsorption surface S1) to the base member 200 (the refrigerant flow path 210 of the base member 200) becomes longer. Since the thermal conductivity of the adhesive layer 170 is lower than the thermal conductivity of the ceramic plate 100, the amount of heat transfer through the adhesive layer 170 is small. In addition, since the thermal conductivity of the filling member 160 is lower than that of the adhesive layer 170, the amount of heat transfer through the filling member 160 is very small. Therefore, in the electrostatic chuck 10X of the comparative example, the heat transfer property (heat drawing characteristic) from the ceramic plate 100 to the base member 200 at the location where the filling member 160 is provided is locally reduced, and the adsorption surface S1 of the ceramic plate 100 There is a risk that the uniformity of the temperature distribution in the lowering.

  FIG. 7 is an explanatory diagram schematically showing a configuration of an electrostatic chuck 10Y of another comparative example. FIG. 7 shows an enlarged configuration of a portion equivalent to the portion (X1 portion) shown in FIG. 4 in the configuration of the electrostatic chuck 10Y of the comparative example. The electrostatic chuck 10Y of the comparative example shown in FIG. 7 differs from the electrostatic chuck 10 of the first embodiment shown in FIG. 4 in the shapes of the recess 140 and the filling member 160. Specifically, in the electrostatic chuck 10Y of the comparative example, the shape of the recess 140 (internal space of the recess 140) is substantially cylindrical in a portion close to the bottom surface 144 (hereinafter referred to as “bottom surface vicinity portion P11”). The remaining part (hereinafter referred to as “opening vicinity P12”) has a substantially cylindrical shape having a diameter larger than that of the bottom vicinity P11. Therefore, in the electrostatic chuck 10Y of the comparative example, in the XZ cross section (that is, the cross section shown in FIG. 7) of the recess 140 passing through the center of the bottom surface 144, the line representing the side surface 142 is stepped (that is, the side surface 142). The line representing the angle has a portion parallel to the surface direction). Since the concave portion 140 in the electrostatic chuck 10Y of the comparative example has such a configuration, a portion (the concave portion specific portion SP2 in FIG. 4) whose width W2 in the surface direction continuously decreases as the width near the bottom surface 144 is approached. I don't have it.

  The size of the opening 146 of the recess 140 in the electrostatic chuck 10Y of the comparative example is the same as the size of the opening 146 of the recess 140 in the electrostatic chuck 10 of the first embodiment. The size of the bottom surface 144 of the recess 140 is the same as the size of the bottom surface 144 of the recess 140 in the electrostatic chuck 10 of the first embodiment.

  In the electrostatic chuck 10Y of the comparative example, the shape of the filling member 160 is substantially cylindrical in a portion close to the bottom surface 164 (hereinafter referred to as “opposing surface vicinity portion P21”), and the remaining portion (hereinafter referred to as “a counter surface vicinity portion P21”). , "Exposed surface vicinity portion P22") has a substantially cylindrical shape having a diameter larger than that of the opposing surface vicinity portion P21. Therefore, in the electrostatic chuck 10Y of the comparative example, in the XZ section of the filling member 160 passing through the center of the bottom surface 164 (that is, the section shown in FIG. 7), the line representing the side surface 162 is stepped (that is, The line representing the side surface 162 has a portion parallel to the surface direction). Since the filling member 160 in the electrostatic chuck 10Y of the comparative example has such a configuration, the portion (the specific portion SP1 in FIG. 4) whose width W1 in the surface direction continuously decreases as it approaches the bottom surface 164. ).

  The size of the exposed surface 166 of the filling member 160 in the electrostatic chuck 10Y of the comparative example is the same as the size of the exposed surface 166 of the filling member 160 in the electrostatic chuck 10 of the first embodiment. The size of the bottom surface 164 of the filling member 160 in the electrostatic chuck 10Y is the same as the size of the bottom surface 164 of the filling member 160 in the electrostatic chuck 10 of the first embodiment.

  Since the electrostatic chuck 10Y of the comparative example shown in FIG. 7 has the above-described configuration, the ceramic plate 100 (the ceramic plate 100) does not pass through the filling member 160 and the adhesive layer 170 (that is, through the ceramic plate 100). The heat transfer path HR from the adsorption surface S1) to the base member 200 (the refrigerant flow path 210 of the base member 200) becomes longer. Therefore, in the electrostatic chuck 10Y of the comparative example, the heat transfer property (heat drawing characteristic) from the ceramic plate 100 to the base member 200 at the location where the filling member 160 is provided is locally reduced, and the adsorption surface S1 of the ceramic plate 100 There is a risk that the uniformity of the temperature distribution in the lowering.

  On the other hand, in the electrostatic chuck 10 of the first embodiment shown in FIG. 4, the filling member 160 includes only the specific portion SP <b> 1 that continuously decreases as the size W <b> 1 in the surface direction becomes closer to the bottom surface 164. Has been. Furthermore, in the electrostatic chuck 10 of the first embodiment, the concave portion 140 faces the specific portion SP1 of the filling member 160 in the surface direction, and continuously decreases as the width W2 in the surface direction approaches the bottom surface 144. It is comprised only from the recessed part specific part SP2. Therefore, in the electrostatic chuck 10 of the first embodiment, the base from the ceramic plate 100 (the adsorption surface S1 of the ceramic plate 100) without passing through the filling member 160 and the adhesive layer 170 (that is, through the ceramic plate 100). The heat transfer path HR reaching the member 200 (the refrigerant flow path 210 of the base member 200) is significantly shorter than the electrostatic chucks 10X and 10Y of the comparative example described above. Therefore, in the electrostatic chuck 10 according to the first embodiment, it is possible to extremely effectively suppress a decrease in heat transfer from the ceramic plate 100 to the base member 200 at the place where the filling member 160 is provided. It is possible to extremely effectively suppress a decrease in temperature distribution uniformity on the adsorption surface S1 of the ceramic plate 100 due to the presence.

  As described above, the recess 140 ensures that the gas supply flow path 220 and the gas ejection flow path 110 communicate with each other even if there is some error in the relative position between the ceramic plate 100 and the base member 200. To be provided. For this reason, if the size of the opening 146 of the recess 140 (and the size of the exposed surface 166 of the filling member 160 filled in the recess 140) is excessively small, the gas supply channel 220 and the gas ejection channel 110 are reliably connected. There is a risk that communication will be hindered. However, in the electrostatic chuck 10 of the first embodiment, as described above, the size of the opening 146 of the recess 140 (and the size of the exposed surface 166 of the filling member 160 filled in the recess 140) is a comparative example. Since the electrostatic chucks 10X and 10Y are ensured in the same manner, the communication failure between the gas supply flow path 220 and the gas ejection flow path 110 due to the positional deviation between the ceramic plate 100 and the base member 200 is prevented. Occurrence can be suppressed.

B. Second embodiment:
FIG. 8 is an explanatory diagram schematically showing the configuration of the electrostatic chuck 10a of the second embodiment. FIG. 8 shows an enlarged configuration of a portion equivalent to the portion (X1 portion) shown in FIG. 4 in the configuration of the electrostatic chuck 10a of the second embodiment. Hereinafter, among the configurations of the electrostatic chuck 10a of the second embodiment, the same configurations as those of the electrostatic chuck 10 of the first embodiment described above (see FIG. 4 and the like) are denoted by the same reference numerals. The description will be omitted as appropriate.

  As shown in FIG. 8, in the electrostatic chuck 10a of the second embodiment, the shape of the recess 140 is different from the configuration of the electrostatic chuck 10 of the first embodiment described above. Specifically, in the electrostatic chuck 10a of the second embodiment, the shape of the concave portion 140 (internal space of the concave portion 140) is substantially cylindrical, as in the comparative example shown in FIG. That is, the opening 146 and the bottom surface 144 of the recess 140 are substantially circular with the same size, and the XZ cross section (that is, the cross section shown in FIG. 8) of the recess 140 passing through the center of the bottom surface 144 is rectangular. is there. The size of the opening 146 of the recess 140 in the electrostatic chuck 10a of the second embodiment is the same as the size of the opening 146 of the recess 140 in the electrostatic chuck 10 of the first embodiment shown in FIG. Therefore, the size of the bottom surface 144 of the recess 140 in the electrostatic chuck 10a of the second embodiment is larger than the size of the bottom surface 144 of the recess 140 in the electrostatic chuck 10 of the first embodiment. Since the recess 140 in the electrostatic chuck 10a of the second embodiment has such a configuration, the width W2 in the surface direction is constant over the whole, and continuously decreases as the width W2 approaches the bottom surface 144. There is no portion (recessed portion SP2 in FIG. 4).

  The configuration of the filling member 160 in the electrostatic chuck 10a of the second embodiment is the same as the configuration of the filling member 160 in the electrostatic chuck 10 of the first embodiment. That is, the bottom surface 164 of the filling member 160 in the electrostatic chuck 10a of the second embodiment has a smaller area than the exposed surface 166 and overlaps the exposed surface 166 as a whole when viewed in the Z-axis direction. In addition, the filling member 160 is composed of only the specific portion SP1 that continuously decreases as the size W1 in the surface direction becomes closer to the bottom surface 164. Therefore, in the electrostatic chuck 10a of the second embodiment, compared to the electrostatic chuck 10 of the first embodiment, the interval between the side surface 162 of the filling member 160 and the side surface 142 of the recess 140 is wide, and is arranged within the interval. The volume of the adhesive layer 170 is increased.

  Since the electrostatic chuck 10a of the second embodiment has the above-described configuration, the ceramic plate 100 (adsorption of the ceramic plate 100) does not pass through the filling member 160 (that is, through the ceramic plate 100 or the adhesive layer 170). The heat transfer path HR from the surface S1) to the base member 200 (the refrigerant flow path 210 of the base member 200) is shorter than that of the electrostatic chucks 10X and 10Y of the comparative example shown in FIGS. Since the thermal conductivity of the adhesive layer 170 is higher than the thermal conductivity of the filling member 160, the heat transfer amount via the adhesive layer 170 is much larger than the heat transfer amount via the filling member 160. Therefore, in the electrostatic chuck 10a of the second embodiment, it is possible to suppress a decrease in heat transfer from the ceramic plate 100 to the base member 200 at the place where the filling member 160 is provided, which is caused by the presence of the filling member 160. A decrease in the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 100 can be suppressed.

  Further, in the electrostatic chuck 10a of the second embodiment, similarly to the electrostatic chuck 10 of the first embodiment described above, the size of the opening 146 of the recess 140 (and the exposure of the filling member 160 filled in the recess 140). Since the size of the surface 166 is ensured to be equal to that of the electrostatic chucks 10X and 10Y of the comparative example shown in FIGS. 6 and 7, the gas caused by the positional deviation between the ceramic plate 100 and the base member 200 Occurrence of a communication failure between the supply channel 220 and the gas ejection channel 110 can be suppressed.

C. Third embodiment:
FIG. 9 is an explanatory diagram schematically showing the configuration of the electrostatic chuck 10b of the third embodiment. FIG. 9 shows an enlarged configuration of a portion equivalent to the portion (X1 portion) shown in FIG. 4 in the configuration of the electrostatic chuck 10b of the third embodiment. Hereinafter, among the configurations of the electrostatic chuck 10b of the third embodiment, the same components as those of the electrostatic chuck 10 of the first embodiment described above (see FIG. 4 and the like) are denoted by the same reference numerals. The description will be omitted as appropriate.

  As shown in FIG. 9, in the electrostatic chuck 10b of 3rd Embodiment, the shape of the recessed part 140 and the filling member 160 differs from the structure of the electrostatic chuck 10 of 1st Embodiment mentioned above. Specifically, in the electrostatic chuck 10b according to the third embodiment, the shape of the filling member 160 is a part close to the bottom surface facing surface 164 (hereinafter, referred to as “opposing surface vicinity portion P21”). Similar to the embodiment, it has a partial conical shape, but the remaining part (hereinafter referred to as “exposed surface vicinity P22”) has a substantially cylindrical shape as in the comparative example shown in FIG. That is, the filling member 160 in the electrostatic chuck 10b of the third embodiment has a C-chamfered corner on the bottom surface 164 side with respect to the filling member 160 in the electrostatic chuck 10X of the comparative example shown in FIG. is there. Further, the shape of the XZ cross section (that is, the cross section shown in FIG. 9) of the filling member 160 passing through the center of the bottom facing surface 164 is a shape in which two corners on the bottom facing surface 164 side in a rectangle are chamfered. Since the filling member 160 in the electrostatic chuck 10b of the third embodiment has such a configuration, the specific portion SP1 (that is, the opposing portion) that continuously decreases as the size W1 in the surface direction becomes closer to the bottom surface 164. It can be said that the surface vicinity portion P21) is included. However, the filling member 160 is not composed of only the specific portion SP1. Further, in the electrostatic chuck 10b of the third embodiment, the bottom surface 164 of the filling member 160 has a smaller area than the exposed surface 166 and is viewed in the Z-axis direction, similarly to the electrostatic chuck 10 of the first embodiment. The entire surface overlaps the exposed surface 166.

  Further, in the electrostatic chuck 10b of the third embodiment, the shape of the concave portion 140 (internal space of the concave portion 140) is a part close to the bottom surface 144 (hereinafter referred to as “bottom surface vicinity portion P11”). Similar to the embodiment, it has a partial conical shape, but the remaining part (hereinafter referred to as “opening vicinity P12”) has a substantially cylindrical shape as in the comparative example shown in FIG. That is, the recess 140 in the electrostatic chuck 10b of the third embodiment has a shape in which a taper is provided at a corner on the bottom surface 144 side with respect to the recess 140 in the electrostatic chuck 10X of the comparative example shown in FIG. Further, the shape of the XZ cross section (that is, the cross section shown in FIG. 9) of the recess 140 passing through the center of the bottom surface 144 is a shape in which two corners on the bottom surface 144 side in a rectangle are chamfered. Since the concave portion 140 in the electrostatic chuck 10b of the third embodiment has such a configuration, the concave portion 140 faces the specific portion SP1 of the filling member 160 in the surface direction, and the width W2 in the surface direction becomes closer to the bottom surface 144. It can be said that the concave portion specifying portion SP2 (that is, the bottom surface vicinity portion P11) that continuously decreases is included. However, the recessed part 140 is not comprised only from recessed part specific part SP2. In the electrostatic chuck 10b of the third embodiment, the side surface 162 in the facing surface vicinity portion P21 of the filling member 160 is substantially parallel to the side surface 142 in the bottom surface vicinity portion P11 of the recess 140.

  Since the electrostatic chuck 10b of the third embodiment has the above-described configuration, the ceramic plate 100 (adsorption of the ceramic plate 100) does not pass through the filling member 160 and the adhesive layer 170 (that is, through the ceramic plate 100). The heat transfer path HR from the surface S1) to the base member 200 (the refrigerant flow path 210 of the base member 200) is shorter than that of the electrostatic chucks 10X and 10Y of the comparative example shown in FIGS. Therefore, in the electrostatic chuck 10b of the third embodiment, it is possible to effectively suppress a decrease in heat transfer from the ceramic plate 100 to the base member 200 at the place where the filling member 160 is provided. It is possible to effectively suppress a decrease in the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 100 due to the above.

  Further, in the electrostatic chuck 10b of the third embodiment, similarly to the electrostatic chuck 10 of the first embodiment described above, the size of the opening 146 of the recess 140 (and the exposure of the filling member 160 filled in the recess 140). Since the size of the surface 166 is ensured to be equal to that of the electrostatic chucks 10X and 10Y of the comparative example shown in FIGS. 6 and 7, the gas caused by the positional deviation between the ceramic plate 100 and the base member 200 Occurrence of a communication failure between the supply channel 220 and the gas ejection channel 110 can be suppressed.

D. Fourth embodiment:
FIG. 10 is an explanatory diagram schematically showing the configuration of the electrostatic chuck 10c of the fourth embodiment. FIG. 10 shows an enlarged configuration of a portion equivalent to the portion (X1 portion) shown in FIG. 4 in the configuration of the electrostatic chuck 10c of the fourth embodiment. Hereinafter, among the configurations of the electrostatic chuck 10c of the fourth embodiment, the configuration of the electrostatic chuck 10 of the first embodiment described above (see FIG. 4 and the like) or the configuration of the electrostatic chuck 10b of the third embodiment (FIG. The description of the same configuration as that of 9) is omitted by attaching the same reference numerals.

  As shown in FIG. 10, in the electrostatic chuck 10c of the fourth embodiment, the shape of the recess 140 is different from the configuration of the electrostatic chuck 10b of the third embodiment described above. Specifically, in the electrostatic chuck 10c of the fourth embodiment, the shape of the corner on the bottom surface 144 side in the recess 140 is not a tapered shape but a concave curved shape. Further, the shape of the XZ cross section (that is, the cross section shown in FIG. 10) of the concave portion 140 passing through the center of the bottom surface 144 is a shape obtained by rounding two corners on the bottom surface 144 side in a rectangle. Since the concave portion 140 in the electrostatic chuck 10c of the fourth embodiment has such a configuration, the concave portion 140 faces the specific portion SP1 of the filling member 160 in the surface direction, and the width W2 in the surface direction becomes closer to the bottom surface 144. It can be said that the concave portion specifying portion SP2 (that is, the bottom surface vicinity portion P11) that continuously decreases is included. However, the recessed part 140 is not comprised only from recessed part specific part SP2.

  The configuration of the filling member 160 in the electrostatic chuck 10c of the fourth embodiment is the same as the configuration of the filling member 160 in the electrostatic chuck 10b of the third embodiment. That is, the bottom surface 164 of the filling member 160 in the electrostatic chuck 10c of the fourth embodiment has a smaller area than the exposed surface 166 and overlaps the exposed surface 166 as a whole when viewed in the Z-axis direction. Further, the filling member 160 is configured to include a specific portion SP1 (that is, a facing surface vicinity portion P21) that continuously decreases as the size W1 in the surface direction becomes closer to the bottom surface facing surface 164. Therefore, in the electrostatic chuck 10c of the fourth embodiment, compared to the electrostatic chuck 10b of the third embodiment, the side surface 142 in the bottom surface vicinity portion P11 of the recess 140 and the side surface 162 in the facing surface vicinity portion P21 of the filling member 160. And the volume of the adhesive layer 170 disposed within the gap is large.

  Since the electrostatic chuck 10c of the fourth embodiment has the above-described configuration, the ceramic plate 100 (adsorption of the ceramic plate 100) does not pass through the filling member 160 and the adhesive layer 170 (that is, through the ceramic plate 100). The heat transfer path HR from the surface S1) to the base member 200 (the refrigerant flow path 210 of the base member 200) is shorter than that of the electrostatic chucks 10X and 10Y of the comparative example shown in FIGS. Therefore, in the electrostatic chuck 10c of the fourth embodiment, it is possible to effectively suppress a decrease in heat transfer from the ceramic plate 100 to the base member 200 at the place where the filling member 160 is provided. It is possible to effectively suppress a decrease in the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 100 due to the above.

  Further, in the electrostatic chuck 10b of the fourth embodiment, the size of the opening 146 of the concave portion 140 (and the exposure of the filling member 160 filled in the concave portion 140 is exposed as in the electrostatic chuck 10 of the first embodiment described above. Since the size of the surface 166 is ensured to be equal to that of the electrostatic chucks 10X and 10Y of the comparative example shown in FIGS. 6 and 7, the gas caused by the positional deviation between the ceramic plate 100 and the base member 200 Occurrence of a communication failure between the supply channel 220 and the gas ejection channel 110 can be suppressed.

E. Fifth embodiment:
FIG. 11 is an explanatory diagram schematically showing the configuration of the electrostatic chuck 10d of the fifth embodiment. FIG. 11 shows an enlarged configuration of a portion equivalent to the portion (X1 portion) shown in FIG. 4 in the configuration of the electrostatic chuck 10d of the fifth embodiment. Hereinafter, among the configurations of the electrostatic chuck 10d of the fifth embodiment, the configuration of the electrostatic chuck 10 of the first embodiment described above (see FIG. 4 and the like) or the configuration of the electrostatic chuck 10b of the third embodiment (see FIG. The description of the same configuration as that of 9) is omitted by attaching the same reference numerals.

  As shown in FIG. 11, in the electrostatic chuck 10d of the fifth embodiment, the shape of the recess 140 is different from the configuration of the electrostatic chuck 10b of the third embodiment described above. Specifically, in the electrostatic chuck 10d of the fifth embodiment, the shape of the concave portion 140 (internal space of the concave portion 140) is substantially cylindrical as in the comparative example shown in FIG. That is, the opening 146 and the bottom surface 144 of the recess 140 are substantially circular with the same size. The size of the opening 146 of the recess 140 in the electrostatic chuck 10d of the fifth embodiment is the same as that of the electrostatic chuck 10 of the first embodiment shown in FIG. 4 or the electrostatic chuck 10b of the third embodiment shown in FIG. The size of the opening 146 of the recess 140 is the same. Therefore, the size of the bottom surface 144 of the recess 140 in the electrostatic chuck 10d of the fifth embodiment is larger than the size of the bottom surface 144 of the recess 140 in the electrostatic chuck 10 of the first embodiment and the electrostatic chuck 10b of the third embodiment. It will be big. Since the recess 140 in the electrostatic chuck 10d according to the fifth embodiment has such a configuration, the width W2 in the surface direction is constant over the entire surface, and continuously decreases as the width W2 approaches the bottom surface 144. There is no portion (recessed portion SP2 in FIG. 4).

  The configuration of the filling member 160 in the electrostatic chuck 10d of the fifth embodiment is the same as the configuration of the filling member 160 in the electrostatic chuck 10b of the third embodiment. That is, the bottom surface 164 of the filling member 160 in the electrostatic chuck 10d of the fifth embodiment has a smaller area than the exposed surface 166 and overlaps the exposed surface 166 as a whole when viewed in the Z-axis direction. Further, the filling member 160 is configured to include a specific portion SP1 (that is, a facing surface vicinity portion P21) that continuously decreases as the size W1 in the surface direction becomes closer to the bottom surface facing surface 164. Therefore, in the electrostatic chuck 10d of the fifth embodiment, the side surface 142 in the bottom surface vicinity portion P11 of the recess 140 and the side surface 162 in the facing surface vicinity portion P21 of the filling member 160 are compared with the electrostatic chuck 10b in the third embodiment. And the volume of the adhesive layer 170 disposed within the gap is large.

  Since the electrostatic chuck 10d of the fifth embodiment has the above-described configuration, the ceramic plate 100 (adsorption of the ceramic plate 100) does not pass through the filling member 160 (that is, through the ceramic plate 100 or the adhesive layer 170). The heat transfer path HR from the surface S1) to the base member 200 (the refrigerant flow path 210 of the base member 200) is shorter than that of the electrostatic chucks 10X and 10Y of the comparative example shown in FIGS. Therefore, in the electrostatic chuck 10d of the fifth embodiment, it is possible to suppress a decrease in heat transfer from the ceramic plate 100 to the base member 200 at the place where the filling member 160 is provided, which is caused by the presence of the filling member 160. A decrease in the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 100 can be suppressed.

  Further, in the electrostatic chuck 10d of the fifth embodiment, similarly to the electrostatic chuck 10 of the first embodiment described above, the size of the opening 146 of the recess 140 (and the exposure of the filling member 160 filled in the recess 140). Since the size of the surface 166 is ensured to be equal to that of the electrostatic chucks 10X and 10Y of the comparative example shown in FIGS. 6 and 7, the gas caused by the positional deviation between the ceramic plate 100 and the base member 200 Occurrence of a communication failure between the supply channel 220 and the gas ejection channel 110 can be suppressed.

F. Sixth embodiment:
FIG. 12 is an explanatory diagram schematically showing the configuration of the electrostatic chuck 10e of the sixth embodiment. FIG. 12 shows an enlarged configuration of a portion equivalent to the portion (X1 portion) shown in FIG. 4 in the configuration of the electrostatic chuck 10e of the sixth embodiment. Hereinafter, among the configurations of the electrostatic chuck 10e of the sixth embodiment, the same components as those of the electrostatic chuck 10 of the first embodiment described above (see FIG. 4 and the like) are denoted by the same reference numerals. The description will be omitted as appropriate.

  As shown in FIG. 12, in the electrostatic chuck 10e of the sixth embodiment, the concave portion 140 is formed on the base member 200 instead of the ceramic plate 100. This is because the electrostatic chuck 10 of the first embodiment described above. Different from the configuration. Specifically, in the electrostatic chuck 10e of the sixth embodiment, a recess 140 having the same configuration as the recess 140 in the electrostatic chuck 10 of the first embodiment is formed on the upper surface S3 of the base member 200. That is, the recess 140 formed in the base member 200 includes a bottom surface 144 that is an inner surface on the side close to the lower surface S4 (see FIG. 2), and a peripheral edge and a bottom surface 144 of the opening 146 (a hole that opens in the upper surface S3) of the recess 140. And a side surface 142 which is an inner surface connecting the peripheral edge of each of the two. A gas supply channel 220 is open at the bottom surface 144 of the recess 140. In the present embodiment, the shape of the concave portion 140 (the internal space of the concave portion 140) is a partial cone (a portion in which the apex side of the cone is missing). That is, both the opening 146 and the bottom surface 144 of the recess 140 are substantially circular. The bottom surface 144 has a smaller area than the opening 146 and overlaps the opening 146 as a whole when viewed in the Z-axis direction. Moreover, the side surface 142 of the recessed part 140 is the shape of the side surface of the said partial cone. Since the recess 140 has such a configuration, it can be said that the recess 140 includes only the recess specifying portion SP2 that continuously decreases as the width W2 in the surface direction approaches the bottom surface 144.

  The recess 140 formed in the base member 200 is filled with a filling member 160 having the same configuration as the filling member 160 in the electrostatic chuck 10 of the first embodiment. That is, the filling member 160 is exposed from the opening 146 of the recess 140 (exposed through the opening 146), the bottom surface 164 facing the bottom surface 144 of the recess 140, and the periphery and bottom surface of the exposure surface 166. A side surface 162 connecting the peripheral edge of the opposing surface 164; In this embodiment, the shape of the filling member 160 is a partial cone (a part of the cone lacking a part on the apex side). That is, both the exposed surface 166 and the bottom surface 164 of the filling member 160 are substantially circular, and the bottom surface 164 has a smaller area than the exposed surface 166 and is entirely exposed to the exposed surface 166 when viewed in the Z-axis direction. Overlap. Further, the side surface 162 of the filling member 160 has a shape of a side surface of the partial cone. Since the filling member 160 has such a configuration, it can be said that the filling member 160 includes only the specific portion SP1 that continuously decreases as the size W1 in the surface direction becomes closer to the bottom surface 164. In the present embodiment, the side surface 162 of the filling member 160 is substantially parallel to the side surface 142 of the recess 140.

  An adhesive layer 170 is disposed between the side surface 142 of the recess 140 and the side surface 162 of the filling member 160, and the filling member 160 is joined to the base member 200 by the adhesive layer 170. In the present embodiment, the bottom surface facing surface 164 of the filling member 160 is in contact with the bottom surface 144 of the recess 140, and the adhesive layer 170 is disposed between the bottom surface facing surface 164 of the filling member 160 and the bottom surface 144 of the recess 140. It has not been.

  As described above, the filling member 160 formed of an insulating material is filled in the concave portion 140, and the adhesive layer 170 is disposed between the side surface 142 of the concave portion 140 and the side surface 162 of the filling member 160. Occurrence of discharge between the ceramic plate 100 and the base member 200 and the discharge of helium gas in the recess 140 via the.

  When helium gas flows into the gas supply flow path 220 inside the base member 200 from the gas source connection hole 221 (FIG. 2), the helium gas that has flowed in is discharged from the gas supply flow path 220 into the recess 140. It passes through the inside of the filling member 160 filled therein and flows into the through hole 310 of the adhesive layer 300, and further, in the first vertical flow path 111 constituting the gas ejection flow path 110 inside the ceramic plate 100. And flows out from the gas ejection holes 102 formed in the adsorption surface S1 through the horizontal flow path 114 and the second vertical flow path 112 (see FIGS. 1 to 3). In this way, helium gas is supplied to the space existing between the suction surface S1 and the surface of the wafer W.

  In the electrostatic chuck 10e of the sixth embodiment shown in FIG. 12, as in the electrostatic chuck 10 of the first embodiment described above, the filling member 160 has a surface direction size W1 that is closer to the bottom surface 164. It consists only of a specific portion SP1 that continuously decreases. Furthermore, in the electrostatic chuck 10e of the sixth embodiment, the concave portion 140 faces the specific portion SP1 of the filling member 160 in the surface direction, and continuously decreases as the width W2 in the surface direction approaches the bottom surface 144. It is comprised only from the recessed part specific part SP2. For this reason, in the electrostatic chuck 10e of the sixth embodiment, the base plate does not pass through the filling member 160 and the adhesive layer 170 (that is, passes through the base member 200) from the ceramic plate 100 (the suction surface S1 of the ceramic plate 100). The heat transfer path HR reaching the member 200 (the refrigerant flow path 210 of the base member 200) is significantly shortened. Therefore, in the electrostatic chuck 10e of the sixth embodiment, it is possible to extremely effectively suppress a decrease in heat transfer from the ceramic plate 100 to the base member 200 at the place where the filling member 160 is provided. It is possible to extremely effectively suppress a decrease in temperature distribution uniformity on the adsorption surface S1 of the ceramic plate 100 due to the presence.

  Further, in the electrostatic chuck 10e of the sixth embodiment, similarly to the electrostatic chuck 10 of the first embodiment described above, the size of the opening 146 of the recess 140 (and the exposure of the filling member 160 filled in the recess 140). Since the size of the surface 166 is ensured to be equal to that of the electrostatic chucks 10X and 10Y of the comparative example shown in FIGS. 6 and 7, the gas caused by the positional deviation between the ceramic plate 100 and the base member 200 Occurrence of a communication failure between the supply channel 220 and the gas ejection channel 110 can be suppressed.

G. Seventh embodiment:
FIG. 13 is an explanatory diagram schematically showing the configuration of the electrostatic chuck 10f of the seventh embodiment. FIG. 13 shows an enlarged configuration of a portion equivalent to the portion (X1 portion) shown in FIG. 4 in the configuration of the electrostatic chuck 10f of the seventh embodiment. Hereinafter, among the configurations of the electrostatic chuck 10f of the seventh embodiment, the same configurations as those of the electrostatic chuck 10 of the first embodiment described above (see FIG. 4 and the like) are denoted by the same reference numerals. The description will be omitted as appropriate.

  As shown in FIG. 13, the electrostatic chuck 10f of the seventh embodiment is different from the configuration of the electrostatic chuck 10 of the first embodiment described above in that a coating layer 180 is provided. Specifically, in the electrostatic chuck 10 f of the seventh embodiment, the side surface 162 and the bottom surface 164 of the filling member 160 are covered with the coating layer 180. In the present embodiment, compared with the configuration of the electrostatic chuck 10 of the first embodiment described above, the thickness of the adhesive layer 170 (the size in the direction perpendicular to the Z axis) is reduced by the amount of the coating layer 180 provided. It has become.

  The thermal conductivity of the coating layer 180 is higher than the thermal conductivity of the adhesive layer 170. As described above, since the thermal conductivity of the adhesive layer 170 is higher than the thermal conductivity of the filling member 160, the thermal conductivity of the coating layer 180 is higher than the thermal conductivity of the filling member 160. As a material for forming the coating layer 180, for example, alumina, yttria, or the like can be used.

  In the electrostatic chuck 10f of the seventh embodiment, as described above, the coating layer 180 having a thermal conductivity higher than the thermal conductivity of the filling member 160 and the adhesive layer 170 has the side surface 162 and the bottom surface 164 of the filling member 160. Therefore, in addition to the ceramic plate 100 and the adhesive layer 170, the coating layer 180 does not pass through the filling member 160 from the ceramic plate 100 (the adsorption surface S1 of the ceramic plate 100) to the base member 200 (base member). A path HR of heat transfer to 200 refrigerant channels 210) is formed. Since the thermal conductivity of the coating layer 180 is higher than the thermal conductivity of the adhesive layer 170, the amount of heat transfer through the path HR is increased when the coating layer 180 forms the above-described heat transfer path HR. Therefore, in the electrostatic chuck 10f according to the seventh embodiment, it is possible to effectively suppress a decrease in heat transfer from the ceramic plate 100 to the base member 200 at the place where the filling member 160 is provided. It is possible to effectively suppress a decrease in the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 100 due to the above.

  In the present embodiment, the coating layer 180 covers the entire side surface 162 and the bottom surface facing surface 164 of the filling member 160, but at least a part of the side surface 162 and the bottom surface facing surface 164 of the filling member 160. A form that covers the region may be employed. For example, the first longitudinal flow of the ceramic plate 100 in the exposed surface 166 of the filling member 160 and the bottom surface 164 of the filling member 160 in order to prevent the coating layer 180 from inhibiting the flow of helium gas. The coating layer 180 may not be formed in a region facing the path 111. If the coating layer 180 is formed so as to cover at least a part of the side surface 162 and the bottom surface 164 of the filling member 160, the coating layer 180 covers at least a part of the above-described heat transfer path HR. Since it can be configured, the amount of heat transfer via the path HR is increased, and it is possible to effectively suppress a decrease in heat transfer from the ceramic plate 100 to the base member 200 at the place where the filling member 160 is provided. It is possible to effectively suppress a decrease in the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 100 due to the presence of the filling member 160.

H. Variation:
The technology disclosed in the present specification is not limited to the above-described embodiment, and can be modified into various forms without departing from the gist thereof. For example, the following modifications are possible.

  The configuration of the electrostatic chuck 10 in each of the above embodiments is merely an example, and can be variously modified. For example, in each of the embodiments described above, the filling member 160 has an exposed surface 166 exposed from the recessed portion 140 and a bottom surface 144 of the recessed portion 140, has a smaller area than the exposed surface 166, and is entirely viewed in the Z-axis direction. And the side surface 162 connecting the periphery of the exposed surface 166 and the periphery of the bottom surface 164, and the size W1 in the surface direction becomes closer to the bottom surface 164. Various modifications are possible as long as it has a specific portion SP1 that continuously decreases. For example, in the first embodiment (FIG. 4), the shape of the filling member 160 is such that the shape of the XZ cross section (that is, the cross section shown in FIG. 4) of the filling member 160 passing through the center of the bottom surface 164 is a trapezoid. However, the shape of the filling member 160 may be such that the side (leg) connecting the two bases of the trapezoid is not a straight line but a curved line. Similarly, in the third embodiment (FIG. 9), the shape of the filling member 160 is the XZ cross section (that is, the cross section shown in FIG. 9) of the filling member 160 passing through the center of the bottom surface 164 is rectangular. The shape of the filling member 160 is such that the two corners on the bottom facing surface 164 side are chamfered. Such a shape may be used.

  Moreover, in each said embodiment, the shape of the recessed part 140 can be variously deformed. For example, in the first embodiment (FIG. 4), the side surface 142 of the recess 140 is substantially parallel to the side surface 162 of the filling member 160, but it is not always necessary for both to be parallel. In the first embodiment, the shape of the recess 140 is such that the shape of the XZ cross section (that is, the cross section shown in FIG. 4) of the recess 140 passing through the center of the bottom surface 144 is a trapezoid. The shape may be such that the side (leg) connecting the two bases in the trapezoid is not a straight line but a curved line.

  In each of the above embodiments, the recess 140 is formed on either the lower surface S2 of the ceramic plate 100 or the upper surface S3 of the base member 200. However, the recess 140 is formed on the lower surface S2 of the ceramic plate 100 and the base member. It may be formed on both of the upper surface S3 of 200. In such a configuration, when helium gas flows into the gas supply channel 220 inside the base member 200 from the gas source connection hole 221 (FIG. 2), the helium gas that has flowed in flows from the gas supply channel 220 to the base member 200. The recesses 140 are discharged into the recesses 140, pass through the filling member 160 filled in the recesses 140, flow into the through holes 310 of the adhesive layer 300, and are further formed in the ceramic plate 100. 140, and passes through the inside of the filling member 160 filled in the concave portion 140 and flows into the first vertical flow path 111 constituting the gas ejection flow path 110 inside the ceramic plate 100. The gas is ejected from the gas ejection holes 102 formed in the adsorption surface S1 through the passage 114 and the second longitudinal flow path 112.

  In the above embodiments, the bottom surface 164 of the filling member 160 is in contact with the bottom surface 144 of the recess 140, but there is a space between the bottom surface 164 of the filling member 160 and the bottom surface 144 of the recess 140. As good as In addition, the adhesive layer 170 may be disposed in all or part of this space. Further, in each of the above embodiments, other configurations for supplying helium gas (gas source connection hole 221, gas supply flow path 220, through hole 310, first vertical flow path 111, horizontal flow path 114, second vertical flow path) The shape, position, number, etc. of the flow path 112, the gas ejection holes 102, etc. can be arbitrarily set. For example, even if the gas ejection flow path 110 does not include the horizontal flow path 114 (that is, a structure in which the first vertical flow path 111 and the second vertical flow path 112 communicate without passing through the horizontal flow path 114). Good.

  In each of the above embodiments, a heater electrode made of a resistance heating element formed of a conductive material (for example, tungsten or molybdenum) may be provided inside the ceramic plate 100. In such a configuration, when a voltage is applied from the power source to the heater electrode, the heater electrode generates heat to warm the ceramic plate 100, and the wafer W held on the suction surface S1 of the ceramic plate 100 is warmed. Thereby, the temperature control of the wafer W is realized. The heater electrode may be arranged not on the inside of the ceramic plate 100 but on the base member 200 side (between the ceramic plate 100 and the adhesive layer 300) of the ceramic plate 100.

  Further, in each of the above embodiments, the refrigerant flow path 210 is formed inside the base member 200. However, the refrigerant flow path 210 is not inside the base member 200 but on the surface of the base member 200 (for example, the base member 200). And the adhesive layer 300).

  In each of the above embodiments, the ceramic plate 100 and the base member 200 are joined by the adhesive layer 300. However, as a joining method of the ceramic plate 100 and the base member 200, other methods (for example, brazing) Or mechanical joining) may be employed.

  Further, in each of the above embodiments, a bipolar system in which a pair of chuck electrodes 400 is provided inside the ceramic plate 100 is adopted, but a single pole system in which one chuck electrode 400 is provided inside the ceramic plate 100. May be adopted. Moreover, the material which forms each member in each said embodiment is an illustration to the last, and each member may be formed with another material.

  Moreover, the manufacturing method of the electrostatic chuck 10 in the above embodiments is merely an example, and various modifications can be made. For example, in each of the above embodiments, the recess 140 is formed by polishing after the ceramic plate 100 is manufactured, but the recess 140 may be formed by drilling a ceramic green sheet before firing. Good.

  In addition, the present invention is not limited to the electrostatic chuck 10 that holds the wafer W using electrostatic attraction, but is provided with a ceramic plate and a base member, and another holding device that holds an object on the surface of the ceramic plate. (For example, it is applicable also to a vacuum chuck, a heater apparatus, etc.).

10: Electrostatic chuck 100: Ceramic plate 102: Gas ejection hole 110: Gas ejection channel 111: First longitudinal channel 112: Second longitudinal channel 114: Horizontal channel 140: Concave portion 142: Side surface 144: Bottom surface 146 : Opening 160: Filling member 162: Side surface 164: Bottom facing surface 166: Exposed surface 170: Adhesive layer 180: Coating layer 200: Base member 210: Refrigerant flow path 220: Gas supply flow path 221: Gas source connection hole 222: Gas Supply hole 300: Adhesive layer 310: Through hole 400: Chuck electrode

Claims (5)

A gas ejection flow path having a planar first surface substantially orthogonal to the first direction and a second surface opposite to the first surface and opening to the first surface A ceramic plate formed inside;
A base member having a third surface, wherein the third surface is disposed to face the second surface of the ceramic plate, and a gas supply channel is formed therein;
A holding device for holding an object on the first surface of the ceramic plate,
At least one of the second surface of the ceramic plate and the third surface of the base member is formed with a recess having a bottom surface in which the gas ejection channel or the gas supply channel opens.
The holding device further includes:
A filling member filled in the recess,
It has air permeability and is formed of an insulating material whose thermal conductivity is lower than the thermal conductivity of the ceramic plate and the member in which the concave portion of the base member is formed,
An exposed surface exposed from the recess, a bottom facing surface that faces the bottom surface of the recess, has a smaller area than the exposed surface, and overlaps the exposed surface as a whole in the first direction; and the exposed surface And a side surface connecting the periphery of the bottom surface facing surface, and a specific portion that continuously decreases as the size in the second direction perpendicular to the first direction approaches the bottom surface facing surface A filling member having
An adhesive layer disposed between the recess and the side surface of the filling member, the thermal conductivity of which is higher than the thermal conductivity of the filling member;
A holding device comprising: The holding device according to claim 1, wherein
The thermal conductivity of the adhesive layer is lower than the thermal conductivity of the ceramic plate and the member formed with the recess in the base member,
The concave portion has a concave portion specific portion that faces the specific portion of the filling member in the second direction and continuously narrows as the width in the second direction approaches the bottom surface. A holding device. The holding device according to claim 1 or 2,
The holding device is characterized in that the filling member is composed of only the specific portion. The holding device according to claim 3, wherein
The thermal conductivity of the adhesive layer is lower than the thermal conductivity of the ceramic plate and the member formed with the recess in the base member,
The concave portion is composed of only the concave specific portion that faces the specific portion of the filling member in the second direction and continuously decreases as the width in the second direction approaches the bottom surface. A holding device. The holding device according to any one of claims 1 to 4, further comprising:
A holding device comprising: a coating layer having a thermal conductivity higher than that of the adhesive layer and covering at least a part of the side surface and the bottom surface of the filling member.

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