JP7233160B2 - Retaining device and method for manufacturing the retaining device - Google Patents

Description

The technology disclosed in this specification relates to a holding device.

For example, in a semiconductor manufacturing apparatus, an electrostatic chuck is used as a holding device for holding a wafer. An electrostatic chuck includes a base member and a ceramic member bonded to the base member, and uses electrostatic attraction generated by applying a voltage to a chuck electrode arranged inside the ceramic member. , the wafer is held by suction on the surface of the ceramic member (hereinafter referred to as "suction surface").

The electrostatic chuck has a configuration for powering the chuck electrodes. Specifically, a terminal through hole is formed inside the base member and opens to a surface of the base member facing the ceramic member (hereinafter referred to as "upper surface"). Connection terminals are arranged. A terminal pad (electrode pad) electrically connected to the chuck electrode is arranged in a predetermined region of the surface of the ceramic member facing the base member (hereinafter referred to as "lower surface"). The predetermined region on the lower surface of the ceramic member is a region that overlaps the terminal through-hole when viewed in a direction substantially orthogonal to the attraction surface (hereinafter referred to as "first direction"). The connection terminals arranged in the terminal through-holes of the base member are joined to the terminal pads by, for example, brazing. During use of the electrostatic chuck, a voltage is applied to the chuck electrode through a conductive path from a power supply through the connection terminals and terminal pads to the chuck electrode.

In such an electrostatic chuck in which terminal pads are bonded to the lower surface of a ceramic member, recesses (also called counterbore) may be formed in the vicinity of the terminal pads. Specifically, on the lower surface of the ceramic member, there are a jig recess having an inner diameter into which a positioning jig for forming connection terminals can be inserted, and a pad recess on the bottom surface of the jig recess. formed. The inner diameter of the pad recess is smaller than that of the jig recess, and terminal pads are arranged on the bottom surface of the pad recess (see, for example, Patent Document 1).

JP 2010-123862 A

In an electrostatic chuck, if the temperature distribution of the attracting surface becomes uneven, the temperature distribution of the wafer held by the attracting surface becomes uneven. Therefore, the electrostatic chuck is required to have the ability to make the temperature distribution of the wafer uniform. On the other hand, the terminal pad tends to become a singular point of the temperature distribution on the attraction surface by generating heat during electrical exchange with the connection terminal. Moreover, since the recess formed in the lower surface of the ceramic member forms a cavity in which ceramic does not exist, it is likely to become a singular point of the temperature distribution on the adsorption surface. In the conventional electrostatic chuck described above, the jig recesses are arranged adjacent to the pad recesses. Corresponding parts are concentrated in a specific part. Therefore, there is a problem that the temperature distribution of the attracting surface becomes non-uniform.

Such a problem is common even when recesses other than the jig recesses are formed on the surface of the ceramic member. Moreover, such a problem is not limited to electrostatic chucks that hold a wafer using electrostatic attraction, but also to holding devices that hold an object on the first surface of a ceramics member. This is a common problem with retainers that have exposed terminal pads on the side second surface.

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

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

(1) The holding device disclosed in this specification includes a ceramic member having a first surface and a second surface opposite to the first surface, and a ceramic member disposed inside the ceramic member. a conductor, a terminal pad exposed on the second surface side of the ceramic member and electrically connected to the conductor, and a connection terminal joined to the terminal pad, wherein the ceramics In a holding device for holding an object on the first surface of a member, the second surface is recessed at a predetermined distance from the terminal pads. A terminal pad tends to become a peculiar point of temperature distribution by generating heat during electrical exchange with a connection terminal. Further, the recess formed on the second surface tends to become a singular point of temperature distribution by forming a cavity in which ceramics does not exist. Therefore, if the recess is formed in the vicinity of the terminal pad, the singular points of the temperature distribution will be concentrated, and as a result, the temperature difference of the temperature distribution on the first surface may increase. On the other hand, according to this holding device, the recess is formed at a position separated from the terminal pad by a predetermined distance. That is, between the terminal pad and the recess, there is a ceramic portion in which heat is relatively easily diffused. As compared with the conventional configuration in which the recesses are continuously formed in the arrangement area of the terminal pads, the recesses disperse the singular points of the temperature distribution. can be made smaller.

(2) In the above holding device, a plurality of recesses may be formed on the second surface. According to this holding device, a plurality of recesses are formed on the second surface. As a result, the plurality of recesses can be used, for example, for positioning the ceramic member and other members while reducing the temperature difference in the temperature distribution on the first surface.

(3) In the above holding device, a plurality of the terminal pads may be arranged on the second surface so as to be surrounded by the plurality of recesses. According to this holding device, the plurality of terminal pads are arranged so as to be surrounded by the plurality of recesses. Accordingly, since the recesses are distributed with respect to the plurality of terminal pads, it is possible to effectively suppress the temperature difference in the temperature distribution on the first surface.

(4) The holding device further has a third surface, the third surface is arranged to face the second surface of the ceramic member, and a housing for housing the connection terminal. The structure may include a support having a space formed thereon, and a joining portion that joins the second surface of the ceramic member and the third surface of the support. According to this holding device, since the space for arranging the terminal pads communicates with the space for accommodating the support, the portion corresponding to the terminal pads on the first surface tends to become a singular point of the temperature distribution. For this reason, applying the present invention is particularly useful.

(5) In the above holding device, the terminal pads on the second surface are positioned relative to at least a portion of an intermediate region between the terminal pads on the second surface and the recesses on the first surface. It is good also as composition located in the side. According to this holding device, since the terminal pads are arranged in the cavity where ceramics do not exist, the portion corresponding to the terminal pads on the first surface tends to become a singular point of the temperature distribution. For this reason, applying the present invention is particularly useful.

(6) A method for manufacturing a holding device disclosed in this specification has a first surface and a second surface opposite to the first surface, and a terminal on the second surface side. preparing a ceramic molded body with exposed pads; firing the ceramic molded body to form a ceramic sintered body; forming recesses at spaced apart positions; and using a jig having protrusions and holding connection terminals, fitting the protrusions into the recesses of the ceramic sintered body, and and bonding the connection terminal held by the terminal pad to the terminal pad. According to the manufacturing method of the holding device, the jig is positioned with respect to the ceramic sintered body by fitting the projection and the recess, so that the connection terminal can be joined to the terminal pad with high accuracy.

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

1 is a perspective view schematically showing an external configuration of an electrostatic chuck 10 according to an embodiment; FIG. It is an explanatory view showing roughly the XZ section composition of electrostatic chuck 10 in an embodiment. It is an explanatory view showing roughly XY section composition of electrostatic chuck 10 in this embodiment. 2 is a bottom view of the ceramic member 100 as seen from the lower surface S2 side. FIG. 4 is a flow chart showing a method of manufacturing the electrostatic chuck 10 according to this embodiment. 6 is an explanatory view schematically showing the XZ cross-sectional configuration of the ceramic member 100 and the jig 600 when bonding the electrode terminal 54 to the electrode pad 52. FIG. FIG. 3 is an explanatory diagram showing the relationship between the XZ cross-sectional configuration of the electrostatic chuck 10 and the temperature distribution according to the present embodiment; FIG. 5 is an explanatory diagram showing the relationship between the XZ cross-sectional configuration of an electrostatic chuck 10A and the temperature distribution in a comparative example; It is the bottom view seen from the lower surface S2A side of 100 A of ceramics members in a comparative example. 6 is an explanatory view schematically showing the XZ cross-sectional configuration of the ceramic member 100A and the jig 600A when bonding the electrode terminal 54 to the electrode pad 52; FIG.

A. Embodiment:
A-1. Configuration of electrostatic chuck 10:
FIG. 1 is a perspective view schematically showing the external configuration of an electrostatic chuck 10 according to this embodiment, and FIG. 2 is an explanatory view schematically showing the XZ cross-sectional configuration of the electrostatic chuck 10 according to this embodiment. 3 is an explanatory view schematically showing the XY cross-sectional configuration of the electrostatic chuck 10 in this embodiment. 2 shows the XZ cross-sectional configuration of the electrostatic chuck 10 at the position II-II in FIG. 3, and FIG. 3 shows the XY cross-sectional configuration of the electrostatic chuck 10 at the position III-III in FIG. It is shown. Each drawing shows mutually orthogonal XYZ axes for specifying directions. In this specification, for the sake of convenience, the positive direction of the Z-axis is referred to as the upward direction, and the negative direction of the Z-axis is referred to as the downward direction. may be

The electrostatic chuck 10 is a device that attracts and holds an object (for example, a wafer W) by electrostatic attraction, and is used, for example, to fix the wafer W within a vacuum chamber of a semiconductor manufacturing apparatus. The electrostatic chuck 10 includes a ceramic member 100 and a base member 200 arranged side by side in a predetermined arrangement direction (vertical direction (Z-axis direction) in this embodiment). The ceramic member 100 and the base member 200 are arranged such that the lower surface S2 (see FIG. 2) of the ceramic member 100 and the upper surface S3 of the base member 200 face each other in the arrangement direction. The electrostatic chuck 10 corresponds to a holding device in claims. Further, the electrostatic chuck 10 corresponds to the support in the claims, the lower surface S2 of the ceramic member 100 corresponds to the second surface in the claims, and the upper surface S3 of the base member 200 corresponds to the second surface in the claims. corresponds to the third surface in the range of

The ceramic member 100 is, for example, a circular planar plate-like member, and is made of ceramics (eg, alumina, aluminum nitride, or the like). The diameter of the ceramic member 100 is, for example, about 50 mm to 500 mm (usually about 200 mm to 450 mm), and the thickness of the ceramic member 100 is, for example, about 1 mm to 10 mm.

As shown in FIG. 2, inside the ceramic member 100, a chuck electrode 400 made of a conductive material (for example, tungsten, molybdenum, etc.) is provided. The shape of the chuck electrode 400 as viewed in the Z-axis direction is, for example, a substantially circular shape. When a voltage is applied to the chuck electrode 400 from a power source (not shown), an electrostatic attraction is generated, and the electrostatic attraction causes the wafer W to move to the surface of the ceramic member 100 opposite to the lower surface S2 (hereinafter referred to as "attraction"). (referred to as "surface S1"). The attraction surface S1 of the ceramic member 100 is a substantially planar surface that is substantially perpendicular to the arrangement direction (Z-axis direction) described above. The adsorption surface S1 of the ceramic member 100 corresponds to the first surface in the claims. Further, in this specification, a direction orthogonal to the Z axis (that is, a direction parallel to the attraction surface S1) is referred to as a "plane direction".

As shown in FIGS. 2 and 3, inside the ceramic member 100, there is provided a heater electrode 500 composed of a resistance heating element made of a conductive material (for example, tungsten, molybdenum, etc.). The shape of the heater electrode 500 as viewed in the Z-axis direction is, for example, a substantially spiral shape. When a voltage is applied to the heater electrode 500 from a power supply (not shown), the heater electrode 500 generates heat, thereby warming the ceramic member 100 and warming the wafer W held on the attraction surface S1 of the ceramic member 100 . Thereby, the temperature control of the wafer W is realized. The heater electrode 500 corresponds to a conductor in claims.

The base member 200 is, for example, a circular planar plate-like member having the same diameter as the ceramic member 100 or having a larger diameter than the ceramic member 100, and is made of metal (aluminum, aluminum alloy, or the like). The diameter of the base member 200 is, for example, approximately 220 mm to 550 mm (usually 220 mm to 470 mm), and the thickness of the base member 200 is, for example, approximately 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, water, or the like) is caused to flow through the coolant channel 210, the base member 200 is cooled, and conduction between the base member 200 and the ceramic member 100 via the adhesive layer 300, which will be described later. The heat cools the ceramic member 100 , thereby cooling the wafer W held on the suction surface S<b>1 of the ceramic member 100 . Thereby, the temperature control of the wafer W is realized.

The ceramic member 100 and the base member 200 are joined together by an adhesive layer 300 arranged between the lower surface S2 of the ceramic member 100 and the upper surface S3 of the base member 200. As shown in FIG. The adhesive layer 300 is made of an adhesive such as silicone resin, acrylic resin, or epoxy resin. The thickness of the adhesive layer 300 is, for example, about 0.1 mm to 1 mm. The adhesive layer 300 corresponds to a joint in the claims.

A-2. Configuration for power supply to heater electrode 500:
Next, a configuration for supplying power to heater electrode 500 will be described. As shown in FIG. 2, inside the base member 200, terminal through-holes 24 are formed that open to the upper surface S3 of the base member 200. As shown in FIG. In the present embodiment, the terminal through hole 24 is a hole that has a circular cross section (a cross section parallel to the surface direction) and penetrates the base member 200 in the Z-axis direction.

A circular concave portion 16 is formed in the lower surface S2 of the ceramic member 100. As shown in FIG. The circular concave portion 16 is formed by denting the chuck electrode 400 side as a whole in a region of the lower surface S2 of the electrostatic chuck 10 that overlaps with the terminal through hole 24 when viewed in the Z-axis direction. In this embodiment, the inner diameter of the circular recess 16 is larger than the inner diameter of the terminal through-hole 24 as viewed in the Z-axis direction, and the circular recess 16 surrounds the terminal through-hole 24 over the entire circumference. At a position between the terminal through-hole 24 formed in the base member 200 and the circular concave portion 16 formed in the ceramic member 100, the adhesive layer 300 has a through-hole extending through the adhesive layer 300 in the Z-axis direction. 32 are formed. Therefore, the terminal through hole 24 formed in the base member 200 and the circular concave portion 16 formed in the ceramic member 100 form an integral hole communicating with each other through the through hole 32 formed in the adhesive layer 300. ing. The terminal through-hole 24 corresponds to an accommodation space in the claims.

A pair of electrode pads 52 electrically connected to heater electrodes 500 via vias 51 are arranged on the bottom surface of the circular recess 16 of the ceramic member 100 . In this embodiment, the shape of the electrode pad 52 as viewed in the Z-axis direction is substantially circular. The electrode pads 52 and vias 51 are made of a conductive material (for example, tungsten, molybdenum, etc.). In addition, as shown in FIG. 2, the electrode pad 52 is entirely exposed from the ceramic member 100 in the thickness direction (Z-axis direction). However, as long as the lower surface of the electrode pad 52 is exposed from the ceramic member 100 , a part or the whole of the electrode pad 52 in the thickness direction may be embedded in the ceramic member 100 .

A pair of columnar electrode terminals 54 extending in the Z-axis direction and a connector 80 are arranged in the terminal through hole 24 formed in the base member 200 . In this embodiment, the cross section of each electrode terminal 54 (the cross section parallel to the surface direction) is circular. The upper end of the electrode terminal 54 is joined to the electrode pad 52 by, for example, metal brazing material. The electrode pads 52 correspond to terminal pads in the claims, and the electrode terminals 54 correspond to connection terminals in the claims. Connector 80 has a connector body 82 and a cable 84 . The connector main body 82 has a substantially rectangular parallelepiped shape, and connection holes 86 are opened in the upper surface of the connector main body 82 at positions facing the respective electrode pads 52 . An electrode terminal 54 is inserted into each connection hole 86 . A cable 84 extends from the lower surface of the connector body 82 . Thereby, each electrode terminal 54 can be electrically connected to an external device via the connector 80 .

The configuration for powering the heater electrode 500 is as described above. When the electrostatic chuck 10 is in use, a voltage is applied to the heater electrode 500 from a power supply (not shown) through a conductive path leading to the heater electrode 500 via the connector 80, the electrode terminals 54, the electrode pads 52 and the vias 51. applied. This causes the heater electrode 500 to generate heat.

The configuration for supplying power to the chuck electrode 400 is the same as the configuration for supplying power to the heater electrode 500 . When the electrostatic chuck 10 is in use, the chuck electrode 400 is supplied with a conductive path from a power source (not shown) to the chuck electrode 400 through connectors, electrode terminals, electrode pads and vias (none of which are shown). , a voltage is applied. As a result, an electrostatic attractive force is generated for attracting and fixing the wafer W to the attracting surface S1.

A-3. Configuration of lower surface S2 of ceramic member 100:
FIG. 4 is a bottom view of the ceramic member 100 before being joined to the base member 200, viewed from the lower surface S2 side. As shown in FIG. 4, the aforementioned circular recess 16 is formed substantially in the center of the lower surface S2 of the ceramic member 100, and a pair of electrode pads 52 are exposed on the bottom surface of the circular recess 16. As shown in FIG. Furthermore, a plurality of (for example, four) positioning recesses 60 are formed in the lower surface S2 of the ceramic member 100 at positions separated from the electrode pads 52 by a predetermined distance. Specifically, each positioning recess 60 is formed at a predetermined distance from the circular recess 16 where the electrode pad 52 is exposed. That is, the intermediate region 102 between the circular recess 16 and the positioning recess 60 is located on the side opposite to the suction surface S1 with respect to both the bottom surface of the circular recess 16 and the bottom surface of the positioning recess 60. there is In short, between the electrode pad 52 (circular recess 16) and the positioning recess 60, there is a ceramic portion whose surface (intermediate region 102) protrudes downward in the plane direction. The diameter of the circular recess 16 is preferably, for example, 7 mm or more and 11.5 mm or less, and the diameter of the positioning recess 60 is preferably, for example, 2 mm or more and 4 mm or less. Also, the distance between the circular recess 16 and the positioning recess 60 is preferably, for example, 1.5 mm or more and 4 mm or less. The vertical depth of the circular recess 16 is preferably 0.6 mm or more and 1.2 mm or less, and the vertical depth of the positioning recess 60 is, for example, 0.3 mm or more and 0.3 mm or more. It is preferably 4 mm or less. Also, the total volume of all (four) positioning recesses 60 is preferably substantially the same as the volume of the circular recess 16 or smaller than the volume of the circular recess 16 .

Also, the four positioning recesses 60 are arranged so as to surround the pair of electrode pads 52 (circular recesses 16). Specifically, the four positioning recesses 60 are arranged at equal intervals in the circumferential direction on the same circle centered on the circular recess 16 . The inner diameter of each positioning recess 60 is smaller than the inner diameter of the circular recess 16 .

On the other hand, as shown in FIG. 2, a plurality of (for example, four) protrusions 202 are formed on the upper surface S3 of the base member 200. As shown in FIG. The four projections 202 are formed at positions facing the four positioning recesses 60 of the ceramic member 100, and each projection 202 is inserted into the positioning recesses 60 facing each other. By inserting the protrusion 202 into the positioning recess 60 in this way, the temperature can be efficiently exchanged between the ceramic member 100 and the base member 200 .

A-4. Manufacturing method of electrostatic chuck 10:
FIG. 5 is a flow chart showing the manufacturing method of the electrostatic chuck 10 in this embodiment, and FIG. It is an explanatory view showing roughly.

First, a ceramic compact and a base member 200 are prepared (S110). The base member 200 can be manufactured by a known manufacturing method. The ceramic molded body is an unsintered body in which the positioning recesses 60 are not formed with respect to the ceramic member 100 described above, and is manufactured by the following method. That is, a plurality of ceramic green sheets (for example, alumina green sheets) are prepared, and metallization ink is printed and perforated for forming the chuck electrode 400, the heater electrode 500, the via 51, the electrode pad 52, etc. on each ceramic green sheet. After processing, etc., a plurality of ceramic green sheets are laminated and thermocompression bonded, cut into a predetermined disk shape, and circular recesses 16 are formed. Thereby, a ceramic compact is formed.

Next, the ceramic compact is fired to form a ceramic sintered body (S120). Next, the ceramics sintered body is subjected to polishing and the like, and at the same time, a hole opening process is performed to form the positioning recesses 60 in the lower surface S2 of the ceramics sintered body (S130). Thereby, the ceramic member 100 is manufactured. Here, assuming that the positioning recesses 60 in the lower surface S2 of the ceramic member 100 are formed by drilling a ceramic green sheet (ceramic molded body) before firing, the ceramic molded body shrinks due to firing. If the positioning recesses 60 or the electrode pads 52 are deformed or misaligned, for example, the electrode terminals 54 may interfere with the base member 200 or the electrode terminals 54 may not be accommodated in the terminal through-holes 24 in the first place. . In contrast, the manufacturing method of the present embodiment can suppress deformation and misalignment of the positioning recesses 60 due to sintering of the ceramic molded body.

Next, the electrode terminal 54 is joined to the electrode pad 52 (S140). Specifically, as shown in FIG. 6, a jig 600 having a pair of insertion holes 610 having an inner diameter substantially equal to the outer diameter of the electrode terminal 54 is installed on the lower surface S2 side of the ceramic member 100. The electrode terminals 54 are positioned by inserting the electrode terminals 54 into the insertion holes 610 of the jig 600, and then joined to the electrode pads 52 by, for example, brazing. A plurality of (for example, four) protrusions 620 are formed on the upper end of the jig 600 used at this time. The jig 600 is positioned by fitting it to the place 60 . At this time, since the electrode pad 52 and the jig 600 are separated from each other by forming the circular concave portion 16 in the ceramic member 100, the jig 600 interferes with the electrode pad 52 and damages the electrode pad 52. is suppressed. After the electrode terminals 54 and the electrode pads 52 are completely joined, the jig 600 is removed.

Next, the ceramic member 100 and the base member 200 are joined (S150). Specifically, in a state in which the electrode terminals 54 are inserted into the terminal through holes 24 of the base member 200, the lower surface S2 of the ceramics member 100 and the upper surface S3 of the base member 200 are opposed to each other, and the ceramics member 100 and the base member 200 are assembled. are joined by an adhesive layer 300. Through the steps described above, the manufacture of the electrostatic chuck 10 having the configuration described above is completed.

A-5. Effect of this embodiment:
A portion of the attraction surface S1 corresponding to the portion directly above the electrode pad 52 is likely to become a singular point of temperature distribution due to heat generated during electrical exchange with the electrode terminal 54 . Also, the portion of the attracting surface S1 corresponding to the portion immediately above the positioning recess 60 formed in the lower surface S2 of the ceramic member 100 tends to become a singular point of the temperature distribution by forming a cavity where no ceramics exists. . Therefore, if the positioning recesses 60 were formed in the vicinity of the electrode pads 52, there would be a singular point of the temperature distribution at a portion of the attraction surface S1 corresponding to the portion immediately above the electrode pads 52 and the positioning recesses 60. As a result, the temperature difference in the temperature distribution of the attraction surface S1 of the ceramic member 100 may increase. In contrast, as described above, in the electrostatic chuck 10 of the present embodiment, the positioning recesses 60 are formed at positions separated from the electrode pads 52 by a predetermined distance. That is, between the electrode pad 52 and the positioning recess 60, there is a ceramic portion in which heat is relatively easily diffused. As compared with the conventional configuration in which the recesses are continuously formed in the arrangement area of the terminal pads, the recesses disperse the singular points of the temperature distribution. temperature difference of the temperature distribution can be reduced.

A specific description will be given below. FIG. 7 is an explanatory diagram showing the relationship between the XZ cross-sectional configuration of the electrostatic chuck 10 and the temperature distribution in this embodiment. FIG. 8 is an explanatory diagram showing the relationship between the XZ cross-sectional configuration of the electrostatic chuck 10A in the comparative example and the temperature distribution, and FIG. FIG. 10 is an explanatory diagram schematically showing the XZ cross-sectional configuration of the ceramic member 100A and the jig 600A when the electrode terminal 54 is joined to the electrode pad 52. As shown in FIG. In addition, regarding the electrostatic chuck 10A of the comparative example, the same reference numerals are assigned to the configurations common to the electrostatic chuck 10 of the present embodiment, and the description thereof is omitted.

As shown in FIGS. 8 and 9, in the electrostatic chuck 10A of the comparative example, a positioning recess 70 is formed in the lower surface S2A of the ceramic member 100A. A pad placement recess 16A having an inner diameter smaller than the inner diameter of the positioning recess 70 is formed. A pair of electrode pads 52 are arranged on the bottom surface of the pad arrangement recess 16A. As shown in FIG. 10, when the electrode terminal 54 is joined to the electrode pad 52, a pair of insertion holes 610A having an inner diameter substantially equal to the outer diameter of the electrode terminal 54 are formed on the lower surface S2A side of the ceramic member 100A. The jig 600A is installed, and the electrode terminals 54 are positioned by inserting the electrode terminals 54 into the insertion holes 610A of the jig 600A, and the electrode terminals 54 are joined to the electrode pads 52 by, for example, brazing. When installing the jig 600 , the jig 600 A is positioned by fitting the upper end of the jig 600 A into the positioning recess 70 of the ceramic member 100 . At this time, since the electrode pad 52 and the jig 600A are separated from each other due to the formation of the pad arrangement recess 16A in the ceramic member 100A, the jig 600A interferes with the electrode pad 52 and the electrode pad 52 is removed. Damage is suppressed.

Thus, in the electrostatic chuck 10A of the comparative example, two-stage recesses of the positioning recess 70 and the circular recess 16 are formed, and a large cavity without ceramics exists around the electrode terminals 54. It will be. Therefore, the peculiar points of the temperature distribution are concentrated on the part corresponding to the part directly above the periphery of the electrode terminal 54 on the attracting surface S1, and as a result, as shown in the lower diagram of FIG. The temperature difference in the temperature distribution of surface S1A may increase.

In contrast, in the electrostatic chuck 10 of the present embodiment, the positioning recesses 60 are formed at positions separated by a predetermined distance from the circular recesses 16 in which the electrode pads 52 are arranged. That is, between the electrode pad 52 (circular concave portion 16) and the positioning concave portion 60, there is a ceramic portion in which heat is relatively easily diffused. Therefore, as shown in the lower diagram of FIG. 7, the singular points of the temperature distribution are suppressed from concentrating on the portion corresponding to the portion directly above the periphery of the electrode terminal 54 on the attracting surface S1. Compared to the electrostatic chuck 10A of the example, the temperature difference in the temperature distribution of the attraction surface S1 of the ceramic member 100 can be reduced.

Further, as the distance between the attraction surface S1 of the ceramic member 100 and the heater electrode 500 becomes shorter, the temperature difference between the portion where the heater electrode 500 exists and the portion where the heater electrode 500 does not exist becomes the temperature at the attraction surface S1 of the ceramic member 100. It becomes easier to influence the distribution. Therefore, in order to improve the heat uniformity of the attraction surface S1 of the ceramic member 100, it is preferable to separate the heater electrode 500 from the attraction surface S1. However, in the electrostatic chuck 10A of the comparative example, since a relatively deep cavity is formed in the lower surface S2A by the two-stage recesses, there is a limit to separating the heater electrode 500 from the adsorption surface S1 (see FIG. 8). etc.). If the heater electrode 500 is further separated from the attracting surface S1, it becomes impossible to form a two-stage recess. On the other hand, in the electrostatic chuck 10 of the present embodiment, since it is not necessary to form two recesses, the heater electrode 500 is spaced further from the attraction surface S1 than in the electrostatic chuck 10A of the comparative example. (See FIG. 1, etc.). Moreover, in the electrostatic chuck 10A of the comparative example, since the relatively large through holes 32A corresponding to the positioning recesses 70 are formed in the specific locations of the adhesive layer 300A, the bonding strength between the ceramic member 100 and the base member 200 is increased. may decrease. On the other hand, in the electrostatic chuck 10 of the present embodiment, since it is not necessary to form a two-stage recess, it is sufficient to form a relatively small through-hole 32 in the adhesive layer 300 . A decrease in the bonding strength with the base member 200 can be suppressed.

Further, according to this embodiment, a plurality of positioning recesses 60 are formed in the lower surface S2 of the ceramic member 100. As shown in FIG. As a result, the plurality of positioning recesses 60 can be used for positioning the ceramic member 100 and another member (the base member 200), for example, while reducing the temperature difference in the temperature distribution of the attraction surface S1 of the ceramic member 100. can be done. Further, it is possible to prevent the jig 600 from rotating with respect to the ceramic member 100 and causing the pair of electrode terminals 54 to be displaced.

Further, in the present embodiment, the terminal through-holes 24 are formed in the base member 200 below the electrode pads 52 in order to secure a space for accommodating the electrode terminals 54, and the cooling effect of the base member 200 is low. . For this reason, the portion corresponding to the portion directly above the periphery of the electrode pad 52 on the attraction surface S1 is particularly likely to become a singular point of the temperature distribution. Therefore, applying this embodiment is particularly useful.

Further, according to the manufacturing method of the present embodiment, the jig 600 is positioned with respect to the ceramic sintered body by fitting the protrusion 202 of the base member 200 and the convex portion 620 of the jig 600, so that the electrode terminal 54 can be joined to the electrode pad 52 with high accuracy.

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

The configuration of the electrostatic chuck 10 in each of the above embodiments is merely an example, and various modifications are possible. For example, in the above embodiment, the heater electrode 500 was exemplified as a conductor, but the present invention is not limited to this, and any member having conductivity disposed inside the ceramic member 100 and electrically connected to the terminal pad can be used. It may be, for example, the chuck electrode 400 (internal electrode) described above. Moreover, although the electrode pad 52 and the electrode terminal 54 electrically connected to the heater electrode 500 have been exemplified as the terminal pad and connection terminal, the electrode pad and electrode electrically connected to the chuck electrode 400 are not limited to this. It may also be a terminal (neither shown).

Further, in the above-described embodiment, the ceramic member 100 and the base member 200 may be joined by a plurality of joining portions instead of the integral adhesive layer 300 . Specifically, a plurality of joints are discretely formed between the ceramic member 100 and the base member 200 and arranged on one virtual plane perpendicular to the facing direction of the ceramic member 100 and the base member 200. It may be A plurality of joint portions also correspond to joint portions in claims.

Further, in the above embodiment, the shapes of the circular recess 16, the positioning recess 60, and the electrode pad 52 as viewed in the Z-axis direction are not limited to circular, and may be other shapes such as rectangular. For example, the positioning recess 60 may be annular surrounding the circular recess 16 or the electrode pad 52 . Also, the inner diameter of the circular recess 16 may be the same as the inner diameter of the terminal through-hole 24 or smaller than the inner diameter of the terminal through-hole 24 . Also, one electrode pad 52 or three or more electrode pads 52 may be arranged in the circular recess 16 . In addition, one, two, three, or five or more circular recesses 16 may be formed in the lower surface S2 of the ceramic member 100 . In addition, in the above-described embodiment, the plurality of circular recesses 16 are arranged on the same circle at regular intervals, but they may be arranged irregularly.

Further, in the above-described embodiment, the protrusion 202 may not be formed on the base member 200 . However, in the configuration of the above-described embodiment, since the projections 202 are formed, the thickness of the adhesive layer 300 in which heat is less likely to diffuse than the ceramic member 100 or the base member 200 in the positioning recess 60 is large. Since the thickening can be suppressed, it is possible to suppress the portion corresponding to the portion directly above the positioning recess 60 on the attracting surface S1 from becoming a singular point of the temperature distribution. Furthermore, in the above-described embodiment, the inner diameter of the terminal through-hole 24 of the base member 200 is larger than the diameter of the circle in which all (four) of the positioning recesses 60 are inscribed, and All of the positioning recesses 60 may be positioned within the terminal through-holes 24 when viewed from the direction).

Further, in the above embodiment, the positioning recess 60 is formed in the lower surface S2 of the ceramic member 100, but the circular recess 16 may not be formed. That is, the surface (intermediate region 102) of the ceramic portion interposed between the electrode pad 52 and the positioning recess 60 is located at least on the opposite side of the bottom surface of the positioning recess 60 from the attracting surface S1. Since the singular points of the temperature distribution are dispersed by the intermediate region 102 and the circular concave portion 16, the temperature difference in the temperature distribution of the attraction surface S1 of the ceramic member 100 can be reduced. good. In other words, "a recess is formed at a predetermined distance from the terminal pad" in the scope of claims means that at least part of the intermediate region between the terminal pad and the recess on the second surface is , located opposite the first surface from the bottom surface of the recess. Also, at least part of the intermediate region is preferably located on the side opposite to the first surface with respect to the bottom surface of the recess and the terminal pad (surface where the terminal pad is exposed).

Further, in the above embodiment, the positioning recesses 60 for positioning the jig 600 and the ceramics member 100 and for preventing misalignment between the ceramics member 100 and the base member 200 are illustrated as the recesses. However, the recesses may be formed for other purposes.

Moreover, in each of the above embodiments, the electrostatic chuck 10 includes the heater electrode 500 , but the electrostatic chuck 10 may not include the heater electrode 500 . Further, in each of the above-described embodiments, the coolant channel 210 is formed inside the base member 200, but the coolant channel 210 is formed not inside the base member 200 but on the surface of the base member 200 (for example, the surface of the base member 200). and the adhesive layer 300).

Further, in each of the above-described embodiments, a monopolar system in which one chuck electrode 400 is provided inside the ceramic member 100 is adopted, but a bipolar system in which a pair of chuck electrodes 400 are provided inside the ceramic member 100 is adopted. may be adopted. Further, the materials forming each member in the electrostatic chuck 10 of each of the above-described embodiments are merely examples, and each member may be formed of another material.

Moreover, the manufacturing method of the electrostatic chuck 10 in each of the above-described embodiments is merely an example, and various modifications are possible. For example, the circular concave portion 16 and the positioning concave portion 60 on the lower surface S2 of the ceramic member 100 may be formed by punching a ceramic green sheet before firing, or by polishing after firing. .

The present invention is not limited to the electrostatic chuck 10 that holds the wafer W using electrostatic attraction, but is applicable to a chuck in which a conductor is disposed inside and terminal pads electrically connected to the conductor are exposed to the outside. It is also applicable to other holding devices (for example, vacuum chucks, heaters, etc.) that have a ceramic member and hold an object on the surface of the ceramic member.

10, 10A: electrostatic chuck 16: circular recess 16A: pad arrangement recess 24: terminal through hole 32: through hole 51: via 52: electrode pad 54: electrode terminal 60, 70: positioning recess 80: connector 82: Connector body 84: Cable 86: Connection hole 100, 100A: Ceramic member 102: Intermediate region 200: Base member 202: Protrusion 210: Coolant flow path 300: Adhesive layer 400: Chuck electrode 500: Heater electrode 600, 600A: Healing Tools 610, 610A: Insertion hole 620: Convex part S1, S1A: Adsorption surface S2, S2A: Lower surface S3: Upper surface W: Wafer

Claims (4)

a ceramic member having a first surface and a second surface opposite to the first surface;
a conductor disposed inside the ceramic member;
a terminal pad exposed on the second surface side of the ceramic member and electrically connected to the conductor;
a connection terminal joined to the terminal pad;
It has a third surface, the third surface is arranged to face the second surface of the ceramic member, and a terminal through-hole, which is an accommodation space for accommodating the connection terminal, is formed. a support;
a joining portion that joins the second surface of the ceramic member and the third surface of the support;
A holding device for holding an object on the first surface of the ceramic member,
The second surface is formed with a terminal recess for accommodating the terminal pad, and a recess for not accommodating the terminal pad is formed at a position separated from the terminal recess by a predetermined distance, and the recess is the depth in the first direction perpendicular to the first surface of is shallower than the depth in the first direction of the terminal recess,
A holding device according to claim 1, wherein no through hole is formed in a portion of the support that overlaps with the recess when viewed in a direction orthogonal to the first surface. A holding device according to claim 1, wherein
A holding device , wherein a plurality of said recesses are formed in said second surface . A holding device according to claim 2 , wherein
wherein the terminal pad is positioned on the first surface side with respect to at least a portion of an intermediate region between the terminal recesses and the recesses on the second surface. Device. preparing a ceramic molded body having a first surface and a second surface opposite to the first surface, with terminal pads exposed on the second surface side;
firing the ceramic molded body to form a ceramic sintered body;
forming a recess at a position spaced apart from the terminal pad by a predetermined distance on the second surface of the ceramic sintered body;
A jig having a projection and holding the connection terminal is used to fit the projection into the recess of the ceramic sintered body, and the connection terminal held by the jig is attached to the terminal pad. and a bonding step.

Images