JP2017157726A - Retainer and manufacturing method of retainer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress reduction in uniformity of temperature distribution in a first surface of a ceramic plate of a retainer.SOLUTION: A retainer includes a tabular ceramic plate having a first surface, a base plate in which a refrigerant flow path is formed, a heater, and a first adhesive layer placed between the ceramic plate and base plate, and retains an object on the first surface of the ceramic plate. A recess is formed in the surface of the ceramic plate on the base plate side, and a gas jet flow path connecting the bottom face of the recess and a gas jet hole, opening to the first surface of the ceramic plate, is formed in the ceramic plate. Furthermore, the retainer includes a filling member having gas permeability formed of an insulating material and filling the recess, and a second adhesive layer interposed between the filling member and the side face of the recess, and bonding the filling member and ceramic plate.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 has a configuration in which a ceramic plate and a base plate are bonded by an adhesive layer (hereinafter referred to as “first adhesive layer”). The electrostatic chuck has an internal electrode, and attracts the wafer to the surface of the ceramic plate (hereinafter referred to as “adsorption surface”) by using electrostatic attraction generated by applying a voltage to the internal electrode. And hold.

  If the temperature distribution of the wafer held by the electrostatic chuck becomes uneven, the accuracy of each process (film formation, etching, exposure, etc.) on the wafer may be reduced. A uniform performance is required. Therefore, when the electrostatic chuck is used, the ceramic plate is heated by a heater arranged inside the ceramic plate or on the base plate side of the ceramic plate, or by cooling by supplying a refrigerant to a refrigerant flow path formed in the base plate. The adsorption surface temperature is controlled.

  In addition, in order to enhance the heat transfer between the ceramic plate and the wafer and further increase the uniformity of the temperature distribution of the wafer, a technology to supply a gas such as helium to the space between the adsorption surface of the ceramic plate and the surface of the wafer Is known (see, for example, Patent Document 1). In this technique, a gas supply path that communicates with a gas supply hole that opens on the surface of the base plate on the ceramic plate side is formed inside the base plate. The first adhesive layer is formed with a through hole that communicates with the gas supply hole of the base plate and penetrates the first adhesive layer in the thickness direction. In addition, a recess that communicates with the through hole is formed on the surface of the ceramic plate on the base plate side, and a gas that opens to the bottom surface (surface closer to the suction surface) of the recess and the suction surface inside the ceramic plate. A gas ejection flow path connecting the ejection holes is formed. When the gas is supplied to the gas supply path of the base plate, the supplied gas passes through the gas supply hole of the base plate, the through hole of the first adhesive layer, the concave portion of the ceramic plate, and the gas injection channel. And is supplied to the space between the suction surface of the ceramic plate and the surface of the wafer.

 Further, in this technique, in order to suppress the occurrence of discharge between the ceramic plate and the base plate via the inside of the recess formed in the ceramic plate and the discharge of gas, the inside of the recess is formed of an insulating material, and the ventilation The filling member (breathable plug) having the property is filled.

JP 2013-232640 A

  In the above conventional technique, the filling member filled in the recess is bonded to the ceramic plate by an adhesive layer (hereinafter referred to as “second adhesive layer”) disposed between the filling member and the bottom surface of the recess. The second adhesive layer is not disposed between the filling member and the side surface of the recess. Therefore, in order to ensure the withstand voltage by the second adhesive layer, it is necessary to relatively increase the size of the concave portion in the radial direction (the direction parallel to the suction surface) to increase the area of the second adhesive layer. .

  Here, since the ceramic plate does not contact the first adhesive layer in the region where the concave portion is formed in the ceramic plate, in this region, the base plate and the ceramic plate are compared with the region where the concave portion is not formed. As a result, the cooling effect of the ceramic plate by the refrigerant supplied to the refrigerant flow path formed in the base plate is reduced. In the above prior art, since the radial dimension of the concave portion needs to be relatively large, a region where the heat transfer between the base plate and the ceramic plate decreases, that is, the cooling effect of the ceramic plate by the refrigerant decreases. There is a problem that the area becomes large and the uniformity of the temperature distribution on the adsorption surface of the ceramic plate may be lowered.

  Such a problem is not limited to an electrostatic chuck that holds a wafer using electrostatic attraction, but is common to a holding device that includes a ceramic plate and a base plate and holds an object on the surface of the ceramic plate. It is a problem.

   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) A holding device disclosed in the present specification includes a plate-shaped ceramic plate having a first surface and a second surface opposite to the first surface, and a third surface. A base plate in which the third surface is arranged to face the second surface of the ceramic plate and a coolant channel is formed; and the interior of the ceramic plate or the ceramic A heater disposed on the base plate side of the plate, and a first adhesive layer disposed between the ceramic plate and the base plate and bonding at least one of the ceramic plate and the heater and the base plate A holding device that holds an object on the first surface of the ceramic plate, and communicates with a gas supply hole that opens in the third surface of the base plate inside the base plate. Gas supply path to The first adhesive layer is formed with a through hole that communicates with the gas supply hole and penetrates the first adhesive layer in the thickness direction. A recess having a bottom surface and a side surface is formed on the surface side of the ceramic plate, and the bottom surface of the recess and the first surface of the ceramic plate are formed inside the ceramic plate. A gas ejection flow path that connects the gas ejection holes that are open to the holding device, and the holding device is further formed of an insulating material and has a gas-permeable filling member filled in the recess, A second adhesive layer that is disposed between the filling member and the side surface of the recess and adheres the filling member and the ceramic plate. According to this holding device, the second adhesive layer that bonds the filling member and the ceramic plate is disposed between the filling member and the side surface of the concave portion, and by ensuring the withstand voltage by the second adhesive layer, Since the discharge between the ceramic plate and the base plate via the inside of the recess and the generation of gas discharge in the recess are suppressed, there is no need to increase the radial dimension of the recess to ensure withstand voltage. . Therefore, according to the present holding device, the radial dimension of the concave portion can be made relatively small, and the region where the cooling effect of the ceramic plate by the refrigerant is lowered can be made relatively small. It can suppress that the uniformity of the temperature distribution in a 1st surface falls.

(2) In the holding device, the second adhesive layer that bonds the filling member and the ceramic plate may be disposed only between the filling member and the side surface of the recess. According to this holding device, since the second adhesive layer is not disposed between the filling member and the bottom surface of the recess, the connection hole with the gas ejection channel on the bottom surface of the recess is blocked by the second adhesive layer. It can suppress that it is suppressed, and it can suppress that the uniformity of the temperature distribution of a holding target object falls.

(3) In the holding device, the filling member may be in contact with the bottom surface of the recess. According to this holding device, since the filling member is in contact with the bottom surface of the concave portion and the space around the filling member can be reduced, the transmission between the base plate and the ceramic plate at the position where the filling member is disposed. A decrease in thermal properties can be suppressed, and a decrease in uniformity of temperature distribution on the first surface of the ceramic plate can be further effectively suppressed. In addition, according to the holding device, since the filling member and the bottom surface of the recess are in contact with each other, compared to the configuration in which a space exists between the filling member and the bottom surface of the recess, Discharge between the base plate and the base plate can be effectively suppressed.

(4) The said holding | maintenance apparatus WHEREIN: The dimension of the depth direction of the said recessed part is good also as a structure larger than the dimension of the radial direction of the said recessed part. According to the holding device, the area of the second adhesive layer disposed between the filling member and the side surface of the recess can be relatively increased by relatively increasing the dimension of the recess in the depth direction. The discharge between the ceramic plate and the base plate via the recess can be more reliably suppressed. In addition, according to the holding device, by reducing the radial dimension of the concave portion, it is possible to reduce the region of the ceramic plate that does not contact the first adhesive layer, and the first surface of the ceramic plate can be reduced. It can suppress more effectively that the uniformity of temperature distribution falls.

(5) The manufacturing method of the holding device disclosed in the present specification includes a plate-shaped ceramic plate having a first surface and a second surface opposite to the first surface, and a third A base plate in which the third surface is arranged to face the second surface of the ceramic plate and a coolant channel is formed; and the interior of the ceramic plate, or A heater disposed on the base plate side of the ceramic plate, a first plate disposed between the ceramic plate and the base plate, and bonding at least one of the ceramic plate and the heater to the base plate. A holding device for holding an object on the first surface of the ceramic plate, the inside of the base plate being open to the third surface of the base plate Gas connected to the gas supply hole A supply path is formed, and the first adhesive layer is formed with a through hole that communicates with the gas supply hole and penetrates the first adhesive layer in the thickness direction. On the second surface side, a concave portion communicating with the through hole and having a bottom surface and a side surface is formed. Inside the ceramic plate, the bottom surface of the concave portion and the first portion of the ceramic plate are formed. A gas ejection flow path that connects a gas ejection hole that is open to the surface of the first gas, and a gas-filling member that is formed of an insulating material and that is filled in the recess and has air permeability; and And a second adhesive layer for bonding the filling member and the ceramic plate, and applying an adhesive to the side surface of the filling member And the adhesive It inserting a coated the filling member in the recess of the ceramic plate, characterized in that it comprises a step of forming the second adhesive layer by curing the adhesive. According to the method for manufacturing the holding device, the second adhesive layer is disposed between the filling member and the side surface of the recess, and is not disposed between the filling member and the bottom surface of the recess. The adhesive layer can be formed.

  The technology disclosed in this specification can be realized in various forms, for example, in the form of a holding device, an electrostatic chuck, a manufacturing method thereof, and the like.

It is a perspective view showing roughly the appearance composition of electrostatic chuck 10 in an embodiment. It is explanatory drawing which shows roughly the XZ cross-sectional structure of the electrostatic chuck 10 in embodiment. It is explanatory drawing which shows roughly the XY cross-sectional structure of the electrostatic chuck 10 in embodiment. It is explanatory drawing which expands and shows the X1 part of FIG. It is a flowchart which shows the manufacturing method of the electrostatic chuck 10 in embodiment. It is explanatory drawing which shows schematically the manufacturing method of the electrostatic chuck 10 in embodiment. It is explanatory drawing which shows roughly the structure of the electrostatic chuck 10a of a comparative example.

A. Embodiment:
A-1. Configuration of the electrostatic chuck 10:
FIG. 1 is a perspective view schematically showing an external configuration of an electrostatic chuck 10 in the present embodiment, and FIG. 2 is an explanatory diagram schematically showing an XZ sectional configuration of the electrostatic chuck 10 in the present embodiment. FIG. 3 is an explanatory diagram schematically showing an XY cross-sectional configuration of the electrostatic chuck 10 according to the present 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 plate 200 arranged side by side in a predetermined arrangement direction (in this embodiment, the vertical direction (Z-axis direction)). The ceramic plate 100 and the base plate 200 are such that the lower surface of the ceramic plate 100 (hereinafter referred to as “ceramic-side adhesive surface S2”) and the upper surface of the base plate 200 (hereinafter referred to as “base-side adhesive surface S3”) are arranged in the arrangement direction. It arrange | positions so that it may oppose. The electrostatic chuck 10 further includes a first adhesive layer 300 disposed between the ceramic side adhesive surface S2 of the ceramic plate 100 and the base side adhesive surface S3 of the base plate 200. The ceramic side adhesive surface S2 of the ceramic plate 100 corresponds to the second surface in the claims, and the base side adhesive surface S3 of the base plate 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.

  A pair of internal electrodes 400 formed of a conductive material (for example, tungsten or molybdenum) is provided inside the ceramic plate 100. When a voltage is applied to the pair of internal electrodes 400 from a power source (not shown), an electrostatic attractive force is generated, and the wafer W is caused to adhere to the upper surface of the ceramic plate 100 (hereinafter referred to as “attracting surface S1”). Adsorbed and fixed to. Note that a plurality of minute protrusions are formed on the suction surface S1 of the ceramic plate 100, and in a state where the wafer W is sucked and fixed to the suction surface S1, a slight amount is provided between the suction surface S1 and the surface of the wafer W. There is space. The adsorption surface S1 of the ceramic plate 100 corresponds to the first surface in the claims. Further, in this specification, a direction parallel to the suction surface S1 is referred to as a “plane direction”.

  Inside the ceramic plate 100, there is provided a heater 500 composed of a resistance heating element formed of a conductive material (for example, tungsten or molybdenum). When a voltage is applied to the heater 500 from a power source (not shown), the heater 500 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 base plate 200 is a circular flat plate member having the same diameter as the ceramic plate 100 or a larger diameter than the ceramic plate 100, and is formed of metal (for example, aluminum or aluminum alloy). The diameter of the base plate 200 is, for example, about 220 mm to 550 mm (usually 220 mm to 350 mm), and the thickness of the base plate 200 is, for example, about 20 mm to 40 mm.

  A coolant channel 210 is formed inside the base plate 200. When a coolant (for example, a fluorine-based inert liquid or water) flows through the coolant channel 210, the base plate 200 is cooled, and the space between the base plate 200 and the ceramic plate 100 via the first adhesive layer 300 is reduced. The ceramic plate 100 is cooled by heat transfer, 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 first adhesive layer 300 includes an adhesive such as a silicone resin, an acrylic resin, or an epoxy resin, for example, and bonds the ceramic plate 100 and the base plate 200 together. The thickness of the first 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 on the lower surface of the base plate 200, and the base side adhesive surface S3 of the base plate 200 has A gas supply hole 222 is opened. Inside the base plate 200, a gas supply path 220 that connects the gas source connection hole 221 and the gas supply hole 222 is formed.

  2 and 4, the first adhesive layer 300 communicates with a gas supply hole 222 formed in the base plate 200, and the first adhesive layer 300 is disposed in the thickness direction (vertical direction). ) Is formed.

  Further, as shown in FIGS. 2 and 4, a concave portion 140 having a bottom surface 144 and a side surface 142 is formed on the ceramic side adhesive surface S2 side of the ceramic plate 100. The recess 140 communicates with the through hole 310 formed in the first adhesive layer 300. Note that the concave portion 140 communicates with the through-hole 310 when the concave portion 140 is in the through-hole 310 in the state where no other members (for example, a filling member 160 and a second adhesive layer 170 described later) exist in the concave portion 140. It means that you are communicating with. Specifically, the recess 140 is formed so as to overlap with the through hole 310 in the thickness direction of the first adhesive layer 300.

  In the present embodiment, the recess 140 has a shape having a substantially circular cross section (cross section parallel to the surface direction) having a diameter R1 over the depth D1. The bottom surface 144 of the recess 140 is a surface on the side close to the suction surface S1 in the recess 140, and is substantially circular in this embodiment. Further, the side surface 142 of the recess 140 is a surface parallel to the thickness direction (vertical direction) of the first adhesive layer 300, and in this embodiment, has a shape like an inner peripheral surface of a cylinder. In this embodiment, the dimension D1 in the depth direction of the recess 140 is larger than the dimension R1 in the radial direction of the recess 140.

  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, inside the ceramic plate 100, a gas ejection flow path that connects a bottom surface 144 (FIG. 4) of the recess 140 formed in the ceramic plate 100 and a gas ejection hole 102 opened in the adsorption surface S 1 of the ceramic plate 100. Is formed. More specifically, the gas ejection channel communicates with the first vertical channel 132 (FIGS. 2 to 4) extending upward from the bottom surface 144 of the recess 140 and the first vertical channel 132 and in the surface direction. And a second vertical flow path 122 (FIG. 2) extending upward from the horizontal flow path 112 and communicating with the gas ejection hole 102.

  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 112 are formed inside the ceramic plate 100. As shown in FIGS. 2 and 3, the lateral flow path 112 closer to the center of the ceramic plate 100 in the two lateral flow paths 112 communicates with the recess 140 shown in the figure via the first longitudinal flow path 132. The four gas ejection holes 102 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 are communicated with each other via the second vertical flow path 122. Further, the lateral flow path 112 far from the center of the ceramic plate 100 in the two horizontal flow paths 112 communicates with the recess 140 (not shown) via the first vertical flow path 132, and the second vertical flow path 112 The four gas ejection holes 102 far from the center of the ceramic plate 100 in the eight gas ejection holes 102 opened to the adsorption surface S <b> 1 are communicated with each other through the flow path 122. The recess 140 (not shown) communicates with a through-hole 310 (not shown) formed in the first adhesive layer 300, similarly to the recess 140 shown in the drawing, and the gas supply path 220 is connected to the through-hole 310. Are communicating.

  As shown in FIGS. 2 and 4, each recess 140 formed in the ceramic plate 100 is filled with a filling member (breathable plug) 160 having air permeability. The filling member 160 is made of an insulating material. 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.

  In the present embodiment, the filling member 160 has a substantially cylindrical shape, and the diameter of the filling member 160 is smaller than the diameter R <b> 1 of the recess 140. Thereby, the filling member 160 can be smoothly inserted into the recess 140. A second adhesive layer 170 is disposed between the side surface of the filling member 160 and the side surface 142 of the recess 140. The second adhesive layer 170 includes an adhesive such as a silicone resin, an acrylic resin, or an epoxy resin. The filling member 160 is joined to the ceramic plate 100 by the second adhesive layer 170.

  In the present embodiment, the upper surface of the filling member 160 is in contact with the bottom surface 144 of the recess 140. That is, the second adhesive layer 170 that bonds the filling member 160 and the ceramic plate 100 is not disposed between the upper surface of the filling member 160 and the bottom surface 144 of the recess 140. Further, the height of the filling member 160 is substantially the same as the depth D1 of the recess 140. Therefore, in the vertical direction, the position of the lower surface of the filling member 160 is substantially the same as the position of the lower surface of the ceramic plate 100.

  As described above, the filling member 160 made of an insulating material is filled in the recess 140, and the second adhesive layer 170 is disposed between the filling member 160 and the side surface 142 of the recess 140. Occurrence of the discharge between the ceramic plate 100 and the base plate 200 and the discharge of the 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 path 220 inside the base plate 200 from the gas source connection hole 221, the helium gas that has flowed in It flows from the supply hole 222 into the through-hole 310 of the first adhesive layer 300, and further passes through the inside of the air-permeable filling member 160 filled in the recess 140, so that the first vertical inside the ceramic plate 100 is formed. The gas flows into the flow channel 132 and is further ejected from the gas ejection holes 102 formed in the adsorption surface S1 through the horizontal flow channel 112 and the second vertical flow channel 122. 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 in the present embodiment. Moreover, FIG. 6 is explanatory drawing which shows roughly the manufacturing method of the electrostatic chuck 10 in this embodiment. First, the ceramic plate 100 and the base plate 200 are prepared (S110). The ceramic plate 100 and the base plate 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 perforation processing, metallizing ink printing, etc. for constituting the internal electrode 400, the heater 500, each gas flow path, and the like. After that, a plurality of ceramic green sheets are laminated and thermocompression bonded, cut into a predetermined disk shape, fired, and finally subjected to polishing or the like, whereby the ceramic plate 100 is manufactured. In the present embodiment, the gas ejection flow path (the first vertical flow path 132, the horizontal flow path 112, the second flow path) that connects the bottom surface 144 of the concave portion 140 and each gas ejection hole 102 that opens to the adsorption surface S1. The longitudinal flow path 122) is formed by performing the drilling process on the ceramic green sheet.

  The base plate 200 is formed with the gas source connection hole 221, the gas supply path 220, and the gas supply hole 222 described above.

  Next, a recess 140 is formed on the ceramic side adhesive surface S2 side of the ceramic plate 100 (S120, see FIG. 6). The recess 140 is formed by, for example, polishing. The recess 140 is formed so as to communicate with the first vertical flow path 132 constituting the gas ejection flow path.

  Next, the adhesive Ad2 is applied to the side surface of the filling member 160 formed of an insulating material (S130, see FIG. 6), and the filling member 160 is inserted into the recess 140 formed in the ceramic plate 100 (S140). At this time, the filling member 160 is pushed in until the upper surface of the filling member 160 contacts the bottom surface 144 of the recess 140. Here, since the adhesive is not applied to the side surface 142 of the recess 140, the adhesive is not pushed into the back side when the filling member 160 is inserted, and does not adhere to the bottom surface 144 of the recess 140. Therefore, when the insertion of the filling member 160 is completed, the adhesive Ad2 is disposed between the filling member 160 and the side surface 142 of the recess 140, and the adhesive is interposed between the filling member 160 and the bottom surface 144 of the recess 140. It will not exist.

  The adhesive Ad2 is a paste formed by mixing an adhesive component (for example, silicone resin, acrylic resin, epoxy resin, etc.) and a powder component (for example, alumina, silica, silicon carbide, silicon nitride, etc.). An adhesive or a paste-like adhesive is applied in the form of a film on a release sheet, for example, and then semi-cured by a curing process to form a gel-like sheet adhesive. The adhesive Ad2 may contain an additive such as a coupling agent.

  Next, the adhesive Ad2 is cured to form the second adhesive layer 170 (S150). The content of the curing process varies depending on the type of adhesive used. If it is a thermosetting adhesive, heat treatment is applied as a curing process. If it is a moisture curing adhesive, the curing process is performed. A process of applying moisture by a method such as humidification is performed. Thereby, the filling member 160 is bonded to the ceramic plate 100.

  Next, by performing a curing process for curing the adhesive Ad1 in a state where the ceramic side adhesive surface S2 of the ceramic plate 100 and the base side adhesive surface S3 of the base plate 200 are bonded together via the adhesive Ad1, The first adhesive layer 300 is formed (S160). The adhesive Ad1 is a paste-like adhesive or a sheet-like adhesive similarly to the above-described adhesive Ad2. Moreover, as above-mentioned as a hardening process, the process (The process which provides heat | fever, the process which provides a water | moisture content) according to the kind of adhesive agent to be used is performed. Further, when the adhesive Ad1 is disposed between the ceramic plate 100 and the base plate 200, a hole corresponding to the above-described through-hole 310 is provided, and the first adhesive layer 300 formed by the curing process of the adhesive Ad1 is provided. A through hole 310 is formed. The operation of bonding at least the ceramic plate 100 and the base plate 200 in the step of S160 is executed when the ceramic plate 100 and the base plate 200 are accommodated in a vacuum sealed container. This is preferable in that air bubbles hardly occur in the adhesive layer 300. With the above steps, the manufacture of the electrostatic chuck 10 having the above-described configuration is completed.

A-3. Effects of the embodiment:
As described above, in the electrostatic chuck 10 of the present embodiment, the gas supply path 220 that communicates with the gas supply hole 222 that opens in the third surface S3 of the base plate 200 is formed in the base plate 200. Yes. Further, the first adhesive layer 300 is formed with a through hole 310 that communicates with the gas supply hole 222 of the base plate 200 and penetrates the first adhesive layer 300 in the thickness direction. Further, on the second surface S <b> 2 side of the ceramic plate 100, a concave portion 140 that communicates with the through hole 310 of the first adhesive layer 300 and has a bottom surface 144 and a side surface 142 is formed. Further, inside the ceramic plate 100, a gas ejection channel (first longitudinal channel 132, which connects the bottom surface 144 of the recess 140 and the gas ejection hole 102 opened to the adsorption surface S 1 of the ceramic plate 100. A transverse channel 112 and a second longitudinal channel 122) are formed. In addition, the electrostatic chuck 10 of the present embodiment is further formed of an insulating material and disposed between the filling member 160 having air permeability filled in the recess 140 and between the filling member 160 and the side surface 142 of the recess 140. And a second adhesive layer 170 that bonds the filling member 160 and the ceramic plate 100 to each other.

  Thus, in the electrostatic chuck 10 of this embodiment, the second adhesive layer 170 that bonds the filling member 160 and the ceramic plate 100 is disposed between the filling member 160 and the side surface 142 of the recess 140. As will be described below, it is possible to suppress a decrease in the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 100.

  FIG. 7 is an explanatory diagram schematically showing the configuration of the electrostatic chuck 10a of the 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 10a of the comparative example. In the electrostatic chuck 10a of the comparative example, the second adhesive layer 170a that bonds the filling member 160a and the ceramic plate 100a is not between the filling member 160a and the side surface 142a of the recess 140a, but between the filling member 160a and the recess 140a. It is arranged between the bottom surface 144a. Also in the electrostatic chuck 10a of the comparative example, the diameter of the filling member 160a is set smaller than the diameter R1 of the recess 140a in order to smoothly insert the filling member 160a into the recess 140a. Therefore, a space Sp exists between the side surface of the filling member 160a and the side surface 142a of the recess 140a. In the electrostatic chuck 10a of the comparative example, the dimension D1 in the depth direction of the recess 140a is smaller than the dimension R1 in the radial direction of the recess 140a.

  In the electrostatic chuck 10a of the comparative example shown in FIG. 7, in order to ensure a withstand voltage by the second adhesive layer 170a disposed between the filling member 160a and the bottom surface 144a of the recess 140a, the radial dimension of the recess 140a. It is necessary to make R1 relatively large to increase the area of the second adhesive layer 170a. Here, since the region where the concave portion 140a is formed in the ceramic plate 100a does not contact the first adhesive layer 300, the heat transfer between the base plate 200 and the ceramic plate 100a is reduced in this region, and as a result, The cooling effect of the ceramic plate 100a by the refrigerant supplied to the refrigerant flow path 210 formed in the base plate 200 is reduced. In the electrostatic chuck 10a of the comparative example, the radial dimension R1 of the concave portion 140a formed in the ceramic plate 100a needs to be relatively large, so that the heat transfer between the base plate 200 and the ceramic plate 100a is reduced. There is a possibility that the region, that is, the region where the cooling effect of the ceramic plate 100a by the refrigerant is lowered is relatively large, and the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 100a is lowered.

  On the other hand, in the electrostatic chuck 10 of the present embodiment, the second adhesive layer 170 that bonds the filling member 160 and the ceramic plate 100 is disposed between the filling member 160 and the side surface 142 of the recess 140. By ensuring the withstand voltage by the second adhesive layer 170, the occurrence of discharge between the ceramic plate 100 and the base plate 200 and the discharge of helium gas in the recess 140 via the recess 140 is suppressed. . Therefore, in the electrostatic chuck 10 of this embodiment, it is not necessary to increase the radial dimension of the recess 140 in order to ensure a withstand voltage. Therefore, in the electrostatic chuck 10 of the present embodiment, since the radial dimension of the recess 140 can be made relatively small, the region where the cooling effect of the ceramic plate 100 by the refrigerant is lowered can be made relatively small, As a result, it can suppress that the uniformity of the temperature distribution in the adsorption | suction surface S1 of the ceramic board 100 falls.

  Further, in the electrostatic chuck 10a of the comparative example, the second adhesive layer 170a that bonds the filling member 160a and the ceramic plate 100a is disposed between the filling member 160a and the bottom surface 144a of the recess 140a. When the firing of the ceramic plate 100a is shifted from the design value or the processing shift of the recess 140a occurs, the gas ejection flow path (first vertical flow path 132) in the bottom surface 144a of the recess 140a is generated. The connection hole may be blocked by the second adhesive layer 170a. When such a blockage occurs, the ejection of helium gas to the adsorption surface S1 side of the ceramic plate 100a is hindered or the uniformity of the amount of helium gas ejection is reduced, and the gap between the ceramic plate 100a and the wafer W is reduced. There is a possibility that the uniformity of the heat transfer is lowered and the uniformity of the temperature distribution of the wafer W is lowered. Note that it is possible to prevent such blockage from occurring by reducing the application amount of the adhesive Ad2 when forming the second adhesive layer 170a. There is a possibility that a portion where the area of the adhesive layer 170a is locally reduced occurs and the withstand voltage is lowered.

  On the other hand, in the electrostatic chuck 10 of the present embodiment, the second adhesive layer 170 that bonds the filling member 160 and the ceramic plate 100 is disposed only between the filling member 160 and the side surface 142 of the recess 140. And is not disposed between the filling member 160 and the bottom surface 144 of the recess 140. Therefore, in the electrostatic chuck 10 of the present embodiment, the connection hole with the gas ejection channel (first vertical channel 132) on the bottom surface 144 of the recess 140 is prevented from being blocked by the second adhesive layer 170. It is possible to suppress the uniformity of the temperature distribution of the wafer W from being lowered.

  In the electrostatic chuck 10a of the comparative example, since the space Sp exists between the side surface of the filling member 160a and the side surface 142a of the recess 140a, the base plate 200 and the ceramic plate 100a are disposed at the position where the filling member 160a is disposed. Heat transfer between the ceramic plate 100a and the uniformity of the temperature distribution on the adsorption surface S1 of the ceramic plate 100a may be greatly reduced.

  On the other hand, in the electrostatic chuck 10 of this embodiment, since the filling member 160 is in contact with the bottom surface 144 of the recess 140, there is no space Sp around the filling member 160. Therefore, in the electrostatic chuck 10 of the present embodiment, it is possible to suppress a decrease in heat transfer between the base plate 200 and the ceramic plate 100 at the position where the filling member 160 is disposed, and the adsorption surface S1 of the ceramic plate 100. It can suppress more effectively that the uniformity of the temperature distribution in falls. Further, in the electrostatic chuck 10 of the present embodiment, the filling member 160 and the bottom surface 144 of the recess 140 are in contact with each other, so that the space Sp is present between the filling member 160 and the bottom surface 144 of the recess 140. Thus, the discharge between the ceramic plate 100 and the base plate 200 via the recess 140 can be effectively suppressed.

  Further, in the electrostatic chuck 10 of this embodiment, the dimension D1 in the depth direction of the recess 140 is larger than the dimension R1 in the radial direction of the recess 140. Therefore, in the electrostatic chuck 10 of the present embodiment, the second adhesive layer disposed between the filling member 160 and the side surface 142 of the concave portion 140 by relatively increasing the dimension D1 of the concave portion 140 in the depth direction. The area of 170 can be made relatively large, and the discharge between the ceramic plate 100 and the base plate 200 via the recess 140 can be more reliably suppressed. Further, in the electrostatic chuck 10 of the present embodiment, by reducing the radial dimension R1 of the concave portion 140, the area of the ceramic plate 100 that does not contact the first adhesive layer 300 can be reduced. It can suppress more effectively that the uniformity of the temperature distribution in adsorption | suction surface S1 of the board 100 falls.

  Further, in the manufacturing method of the electrostatic chuck 10 of the present embodiment, the step of applying the adhesive Ad2 to the side surface of the filling member 160 (S130 in FIG. 5), and the filling member 160 is inserted into the recess 140 of the ceramic plate 100. A step (S140) and a step (S150) of forming the second adhesive layer 170 by curing the adhesive Ad2. According to this manufacturing method, the second adhesive layer 170 is disposed between the filling member 160 and the side surface 142 of the recess 140 and is not disposed between the filling member 160 and the bottom surface 144 of the recess 140. In addition, the second adhesive layer 170 can be formed.

B. Variations:
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 the above embodiment is merely an example, and can be variously modified. For example, in the above embodiment, a configuration for supplying helium gas (a gas source connection hole 221, a gas supply path 220, a gas supply hole 222, a through hole 310, a recess 140, a first vertical flow path 132, a horizontal flow path 112, The shape, position, number, and the like of the second vertical flow path 122 and the gas ejection holes 102 can be arbitrarily set.

  In the above embodiment, the top surface of the filling member 160 is in contact with the bottom surface 144 of the recess 140, but a space may exist between the top surface of the filling member 160 and the bottom surface 144 of the recess 140. In addition, an adhesive layer may be disposed in all or part of this space.

  Moreover, the material which forms each member in the said embodiment is an illustration to the last, and each member may be formed with another material. Further, in the above embodiment, the heater 500 is arranged inside the ceramic plate 100. However, the heater 500 is not inside the ceramic plate 100 but on the base plate 200 side of the ceramic plate 100 (the ceramic plate 100 and the first plate). Between the adhesive layer 300 and the adhesive layer 300. In this case, the first adhesive layer 300 adheres at least one of the ceramic plate 100 and the heater 500 and the base plate 200.

  In the above embodiment, the refrigerant flow path 210 is formed inside the base plate 200. However, the refrigerant flow path 210 is not inside the base plate 200, but the surface of the base plate 200 (for example, the base plate 200 and the like). It may be formed between the first adhesive layer 300 and the first adhesive layer 300. Further, in the above embodiment, a bipolar system in which a pair of internal electrodes 400 is provided inside the ceramic plate 100 is adopted, but a monopolar system in which one internal electrode 400 is provided inside the ceramic plate 100 is employed. It may be adopted.

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

  The present invention is not limited to the electrostatic chuck 10 that holds the wafer W using electrostatic attraction, and includes other ceramic holding plates (for example, a ceramic plate and a base plate) that hold an object on the surface of the ceramic plate (for example, , Vacuum chuck, etc.).

DESCRIPTION OF SYMBOLS 10: Electrostatic chuck 100: Ceramics plate 102: Gas ejection hole 112: Horizontal flow path 122: 2nd vertical flow path 132: 1st vertical flow path 140: Concave part 142: Side surface 144: Bottom surface 160: Filling member 170: 1st 2: Adhesive layer 200: Base plate 210: Refrigerant flow path 220: Gas supply path 221: Gas source connection hole 222: Gas supply hole 300: First adhesive layer 310: Through hole 400: Internal electrode 500: Heater

Claims (5)

A plate-like ceramic plate having a first surface and a second surface opposite to the first surface;
A base plate having a third surface, wherein the third surface is disposed so as to face the second surface of the ceramic plate, and a coolant channel is formed;
A heater disposed in the ceramic plate or on the base plate side of the ceramic plate;
A first adhesive layer disposed between the ceramic plate and the base plate and bonding at least one of the ceramic plate and the heater and the base plate;
A holding device for holding an object on the first surface of the ceramic plate,
Inside the base plate, a gas supply path communicating with a gas supply hole opening in the third surface of the base plate is formed,
The first adhesive layer has a through hole that communicates with the gas supply hole and penetrates the first adhesive layer in the thickness direction.
On the second surface side of the ceramic plate, a concave portion that communicates with the through hole and has a bottom surface and a side surface is formed.
Inside the ceramic plate, there is formed a gas ejection flow path that connects the bottom surface of the recess and a gas ejection hole that opens to the first surface of the ceramic plate,
The holding device further includes:
A filling member made of an insulating material and having air permeability filled in the recess;
A second adhesive layer disposed between the filling member and the side surface of the recess, and bonding the filling member and the ceramic plate;
A holding device comprising: The holding device according to claim 1, wherein
The holding device, wherein the second adhesive layer that bonds the filling member and the ceramic plate is disposed only between the filling member and the side surface of the recess. The holding device according to claim 1 or 2,
The holding device, wherein the filling member is in contact with the bottom surface of the recess. In the holding device according to any one of claims 1 to 3,
The holding device according to claim 1, wherein a dimension of the concave portion in a depth direction is larger than a radial dimension of the concave portion. A plate-shaped ceramic plate having a first surface and a second surface opposite to the first surface, and a plate-shaped ceramic plate having a third surface, wherein the third surface is the ceramics A base plate disposed so as to face the second surface of the plate and having a coolant channel formed therein; a heater disposed in the ceramic plate or on the base plate side of the ceramic plate; A first adhesive layer that is disposed between the ceramic plate and the base plate and bonds at least one of the ceramic plate and the heater and the base plate; and the first surface of the ceramic plate A holding device for holding an object on the top, wherein a gas supply path communicating with a gas supply hole opened in the third surface of the base plate is formed inside the base plate, 1 adhesive layer has A through hole that communicates with the gas supply hole and penetrates the first adhesive layer in the thickness direction is formed, and the second surface side of the ceramic plate communicates with the through hole and has a bottom surface. And a side surface, and a gas jet flow connecting the bottom surface of the concave portion and a gas jet hole opening in the first surface of the ceramic plate inside the ceramic plate. A passage is formed, and is further formed of an insulating material, and has a breathable filling member filled in the recess, and is disposed between the filling member and the side surface of the recess, and the filling member In a manufacturing method of a holding device comprising: a second adhesive layer that bonds the ceramic plate;
Applying an adhesive to the side surface of the filling member;
Inserting the filling member coated with the adhesive into the recess of the ceramic plate;
Curing the adhesive to form the second adhesive layer;
A method for manufacturing a holding device.

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