JP6994953B2 - Holding device - Google Patents

Description

The techniques disclosed herein relate to holding devices that hold objects.

For example, an electrostatic chuck is used as a holding device for holding a wafer when manufacturing a semiconductor. The electrostatic chuck is provided inside a ceramic member having a substantially planar surface (hereinafter referred to as “adsorption surface”) substantially perpendicular to a predetermined direction (hereinafter referred to as “first direction”) and inside the ceramic member. It is equipped with a chuck electrode, and the wafer is adsorbed and held on the adsorption surface of the ceramic member by utilizing the electrostatic attraction generated by applying a voltage to the chuck electrode.

If the temperature of the wafer held on the suction surface of the electrostatic chuck does not reach the desired temperature, the accuracy of each process (deposition, etching, etc.) on the wafer may decrease. Therefore, the temperature of the wafer is applied to the electrostatic chuck. Performance to control the distribution is required. Therefore, for example, a plurality of heater electrodes are provided inside the ceramic member. When a voltage is applied to each heater electrode, the ceramic member is heated by the heat generated by each heater electrode, thereby controlling the temperature distribution of the suction surface of the ceramic member (and by extension, the temperature of the wafer held on the suction surface). Distribution control) is realized.

Each heater electrode has a heater line portion which is a linear resistance heating element and a heater pad portion connected to each end of the heater line portion (see, for example, Patent Document 1). Further, in order to supply power to each heater electrode, the electrostatic chuck may be provided with a driver electrode having a conductive region (see, for example, Patent Document 2). The conductive region of the driver electrode is electrically connected to the feeding terminal via the feeding side via, and is also electrically connected to the heater pad portion of each heater electrode via the heater side via. In such a configuration, the heater pad portion of each heater electrode is connected to the power supply via the heater side via, the conductive region of the driver electrode, the feeding side via, and the feeding terminal.

Japanese Unexamined Patent Publication No. 2016-139503 Japanese Unexamined Patent Publication No. 2015-018704

In the heater electrode, the width of the heater pad portion in the first directional view is larger than the width of the heater line portion, so that the amount of heat generated by the heater pad portion is very small as compared with the amount of heat generated by the heater line portion. Is. Therefore, in the conventional electrostatic chuck, in the suction surface of the ceramic member, the region overlaps the heater pad portion in the first direction view, or the region opposite to the extension direction of the heater line portion with respect to the heater pad portion. The overlapping region tends to be a low temperature temperature singularity. Therefore, in the conventional electrostatic chuck, there is room for improvement in terms of controllability of the temperature distribution of the suction surface of the ceramic member (and by extension, controllability of the temperature distribution of the wafer).

It should be noted that such a problem is not limited to the electrostatic chuck that holds the wafer by utilizing electrostatic attraction, but is a common problem in general for holding devices provided with a ceramic member and holding an object on the surface of the ceramic member. ..

This specification discloses a technique capable of solving the above-mentioned problems.

The techniques disclosed herein can be realized, for example, in the following forms.

(1) The holding device disclosed in the present specification includes a ceramic member having a substantially planar first surface substantially perpendicular to the first direction, and a plurality of heater electrodes arranged inside the ceramic member. They are connected to the heater line portion, which is a linear resistance heating element in the first direction view, and the end portion of the heater line portion, respectively, and from the heater line portion in the first direction view. A plurality of heater electrodes having a wide heater pad portion, a driver electrode arranged inside the ceramics member and including a conductive region, a feeding terminal, and the feeding terminal and the conductive region of the driver electrode are provided. The first via of the ceramic member, comprising a feeding side via that is electrically connected and a heater side via that electrically connects the heater pad portion of each heater electrode and the conductive region of the driver electrode. In a holding device for holding an object on a surface, the heater line passes through the center point of the heater pad portion and is connected to the heater pad portion and the heater line portion in the first directional view. The virtual straight line parallel to the extending direction of the portion is defined as the first virtual straight line, and the two virtual straight lines passing through the center point and forming an angle of 45 degrees with the first virtual straight line are the second and third virtual straight lines, respectively. When it is a virtual straight line, the power feeding terminal is located in the first region facing the connection portion with the center point in between, among the four regions separated by the second and third virtual straight lines. .. In the heater electrode, in the first directional view, the heater pad portion has a width larger than that of the heater line portion, so that the amount of heat generated by the heater pad portion is very small as compared with the amount of heat generated by the heater line portion. Therefore, in the first surface of the ceramic member, a region overlapping the heater pad portion and a region overlapping the heater pad portion on the side opposite to the extending direction of the heater line portion in the first directional view (hereinafter,). , "Specific region") tends to be a low temperature temperature singularity. When a low temperature temperature singularity is generated on the first surface of the ceramic member, the controllability of the temperature distribution on the first surface is lowered, and eventually the controllability of the temperature distribution of the object held by the holding device is lowered. .. However, in this holding device, the power feeding terminal has the heater pad portion and the heater line portion with the center point of the heater pad portion in the four regions separated by the second virtual straight line and the third virtual straight line. It is located in the first region facing the connection portion of. The first region is a region that includes most of the specific region that tends to be the above-mentioned low temperature temperature singularity. Therefore, in the conductive region of the driver electrode, the heat generated by the current flowing in the vicinity of the straight line connecting the heater pad portion and the feeding terminal located in the first region in the first directional view causes the above-mentioned specific region to have a low temperature. It is possible to suppress the temperature singularity. Therefore, according to this holding device, it is possible to suppress the generation of a low temperature temperature singularity on the first surface of the ceramic member, and the controllability of the temperature distribution on the first surface of the ceramic member (and by extension, the target). Controllability of temperature distribution of objects) can be improved.

(2) In the holding device, the feeding terminal may be configured to be located on the first virtual straight line in the first directional view. Of the above-mentioned specific regions, the position on the first virtual straight line tends to be a temperature singularity at a particularly low temperature. In this holding device, the feeding terminal is located on the first virtual straight line in the first directional view. Therefore, according to this holding device, heat is generated by the current flowing in the conductive region of the driver electrode in the vicinity of the straight line connecting the heater pad portion and the feeding terminal located on the first virtual straight line in the first directional view. As a result, it is possible to effectively suppress the specific region from becoming a low-temperature temperature singularity, and the controllability of the temperature distribution on the first surface of the ceramic member (and thus the controllability of the temperature distribution of the object) is effective. Can be improved.

(3) In the holding device, when the first region is divided into first and second small regions by the first virtual straight line in the first directional view, the power feeding terminal is the first. And, in the second small area, the heater line portion extended from the connection portion is located in a direction opposite to the direction away from the first virtual straight line with respect to the first virtual straight line. It may be configured to be located in a small area. Among the above-mentioned specific regions, especially in a small region where the heater line portion extended from the connection portion between the heater pad portion and the heater line portion is located in the direction opposite to the direction away from the first virtual straight line, the temperature is particularly low. It tends to be a temperature singularity. In this holding device, since the feeding terminal is located in such a small region that tends to be a temperature singularity at a particularly low temperature in the first directional view, the heater in the conductive region of the driver electrode is the heater in the first directional view. It is possible to effectively suppress that a specific region becomes a low temperature singular point due to heat generated by the current flowing near the straight line connecting the pad portion and the feeding terminal located in the small region, and the ceramic member. It is possible to effectively improve the controllability of the temperature distribution of the first surface (and thus the controllability of the temperature distribution of the object).

(4) In the holding device, in the first directional view, the portion between the power feeding terminal and the heater pad portion in the first virtual straight line overlaps with the heater line portion, and the heater line The portion of the portion that overlaps with the first virtual straight line may have a larger width than at least a portion of the heater line portion that does not overlap with the first virtual straight line. The position of the portion of the heater line portion that overlaps with the first virtual straight line (hereinafter referred to as "overlapping portion") is, in addition to the heat generated from the overlapping portion, the heater in the conductive region of the driver electrode in the first directional view. Since heat is generated by the current flowing near the straight line connecting the pad and the power supply terminal, it tends to be a high temperature singular point. In this holding device, the overlapping portion in the heater line portion is wider than at least a portion that does not overlap with the first virtual straight line in the heater line portion. Therefore, the calorific value of the overlapping portion in the heater line portion is smaller than the calorific value of the other portion in the heater line portion. Therefore, according to this holding device, it is possible to suppress the generation of high-temperature temperature singularities on the first surface of the ceramic member, and the controllability of the temperature distribution on the first surface of the ceramic member (and by extension, the target). The controllability of the temperature distribution of an object) can be effectively improved.

(5) In the holding device, the conductive region is connected to the heater pad portions of the plurality of heater electrodes via the heater side via, and the heater pad is one in the first directional view. The virtual line segment connecting the center point of the portion and the center point of the other heater pad portion may be configured to pass through a region other than the conductive region. In this holding device, since the virtual line segment connecting the center point of one heater pad portion and the center point of the other heater pad portion passes through a region other than the conductive region, the driver electrode has a conductive region. The path of the current flowing between each heater pad portion and the feeding terminal in the first directional view can be a path close to a straight line connecting each heater pad portion and the feeding terminal. Therefore, according to this holding device, in the conductive region of the driver electrode, the above-mentioned specific region becomes a low temperature temperature singularity due to heat generated by the current flowing between each heater pad portion and the feeding terminal in the first direction view. This can be effectively suppressed, and the controllability of the temperature distribution on the first surface of the ceramic member (and thus the controllability of the temperature distribution of the object) can be effectively improved.

The technique disclosed in the present specification can be realized in various forms, for example, a holding device, an electrostatic chuck, a heater device such as a CVD heater, a vacuum chuck, and a method for manufacturing them. It is possible to realize with.

It is a perspective view which shows schematic appearance structure of the electrostatic chuck 100 in 1st Embodiment. It is explanatory drawing which shows schematic the XZ cross-sectional structure of the electrostatic chuck 100 in 1st Embodiment. It is explanatory drawing which shows schematic the XY plane (top surface) structure of the electrostatic chuck 100 in 1st Embodiment. It is explanatory drawing which shows typically the XY cross-sectional structure of one heater electrode 500 arranged in one segment SE. It is explanatory drawing which shows the positional relationship between the feeding terminal and a heater pad part in the electrostatic chuck 100 of this embodiment. It is explanatory drawing which shows the positional relationship between the feeding terminal and a heater pad part in the electrostatic chuck 100 of this embodiment. It is explanatory drawing which shows the positional relationship between the feeding terminal and a heater pad part in the electrostatic chuck 100 of 2nd Embodiment. It is explanatory drawing which shows the structure of the driver electrode 60 in the electrostatic chuck 100 of 3rd Embodiment.

A. First Embodiment:
A-1. Configuration of electrostatic chuck 100:
FIG. 1 is a perspective view schematically showing an external configuration of the electrostatic chuck 100 according to the first embodiment, and FIG. 2 is an explanatory view schematically showing an XZ cross-sectional configuration of the electrostatic chuck 100 according to the first embodiment. FIG. 3 is an explanatory diagram schematically showing the XY plane (upper surface) configuration of the electrostatic chuck 100 in the first embodiment. Each figure shows XYZ axes that are orthogonal to each other to identify the direction. In the present specification, for convenience, the Z-axis positive direction is referred to as an upward direction, and the Z-axis negative direction is referred to as a downward direction, but the electrostatic chuck 100 is actually installed in a direction different from such an orientation. May be done.

The electrostatic chuck 100 is a device that attracts and holds an object (for example, a wafer W) by electrostatic attraction, and is used for fixing the wafer W in a vacuum chamber of a semiconductor manufacturing apparatus, for example. The electrostatic chuck 100 includes a ceramic member 10 and a base member 20 arranged side by side in a predetermined arrangement direction (in the present embodiment, the vertical direction (Z-axis direction)). The ceramic member 10 and the base member 20 are arranged so that the lower surface S2 (see FIG. 2) of the ceramic member 10 and the upper surface S3 of the base member 20 face each other in the arrangement direction.

The ceramic member 10 is a plate-shaped member having a substantially circular planar upper surface (hereinafter referred to as “adsorption surface”) S1 substantially orthogonal to the above-mentioned arrangement direction (Z-axis direction), and is a ceramic (for example, alumina or aluminum nitride). Etc.). The diameter of the ceramic member 10 is, for example, about 50 mm to 500 mm (usually about 200 mm to 350 mm), and the thickness of the ceramic member 10 is, for example, about 1 mm to 10 mm. The suction surface S1 of the ceramic member 10 corresponds to the first surface in the claims, and the Z-axis direction corresponds to the first direction in the claims. Further, in the present specification, the direction orthogonal to the Z-axis direction is referred to as "plane direction", and as shown in FIG. 3, the circumferential direction centered on the center point Px of the suction surface S1 is "plane direction". It is called "circumferential direction CD", and the direction orthogonal to the circumferential direction CD in the plane direction is called "diametrical direction RD".

As shown in FIG. 2, a chuck electrode 40 made of a conductive material (for example, tungsten, molybdenum, platinum, etc.) is arranged inside the ceramic member 10. The shape of the chuck electrode 40 in the Z-axis direction is, for example, substantially circular. When a voltage is applied to the chuck electrode 40 from a power source (not shown), an electrostatic attraction is generated, and the wafer W is attracted and fixed to the suction surface S1 of the ceramic member 10 by this electrostatic attraction.

Inside the ceramic member 10, there is also a heater electrode layer 50 for controlling the temperature distribution of the suction surface S1 of the ceramic member 10 (that is, controlling the temperature distribution of the wafer W held on the suction surface S1), and a heater. A configuration for supplying power to the electrode layer 50 is arranged. These configurations will be described in detail later. For the ceramic member 10 having such a configuration, for example, a plurality of ceramic green sheets are produced, and via holes are formed in a predetermined ceramic green sheet, metallized paste is filled, and printing is performed on these ceramic green sheets. The sheet can be produced by thermocompression bonding, processing such as cutting, and then firing.

The base member 20 is, for example, a circular flat plate-shaped member having the same diameter as the ceramic member 10 or having a diameter larger than that of the ceramic member 10, and is formed of, for example, a metal (aluminum, an aluminum alloy, or the like). The diameter of the base member 20 is, for example, about 220 mm to 550 mm (usually 220 mm to 350 mm), and the thickness of the base member 20 is, for example, about 20 mm to 40 mm.

The base member 20 is joined to the ceramic member 10 by an adhesive layer 30 arranged between the lower surface S2 of the ceramic member 10 and the upper surface S3 of the base member 20. The adhesive layer 30 is made of an adhesive material such as a silicone resin, an acrylic resin, or an epoxy resin. The thickness of the adhesive layer 30 is, for example, about 0.1 mm to 1 mm.

A refrigerant flow path 21 is formed inside the base member 20. When a refrigerant (for example, a fluorine-based inert liquid, water, etc.) is flowed through the refrigerant flow path 21, the base member 20 is cooled, and heat transfer (heat transfer between the base member 20 and the ceramic member 10 via the adhesive layer 30). The ceramic member 10 is cooled by heat transfer), and the wafer W held on the suction surface S1 of the ceramic member 10 is cooled. As a result, control of the temperature distribution of the wafer W is realized.

A-2. Configuration of heater electrode layer 50, etc .:
Next, the configuration of the heater electrode layer 50 and the configuration for supplying power to the heater electrode layer 50 will be described in detail.

As described above, the electrostatic chuck 100 includes a heater electrode layer 50 (see FIG. 2). The heater electrode layer 50 is made of a conductive material (for example, tungsten, molybdenum, platinum, etc.). In this embodiment, the heater electrode layer 50 is arranged below the chuck electrode 40.

The heater electrode layer 50 includes a plurality of heater electrodes 500 (see FIG. 4). Here, as shown in FIG. 3, in the present embodiment, a plurality of virtual regions SE are set in the ceramic member 10. More specifically, in the Z-axis direction, the ceramic member 10 has a plurality of virtual annular regions (provided to be centered) by a plurality of concentric first boundary lines BL1 centered on the center point Px of the suction surface S1. Only the region containing the point Px is divided into circular regions), and each annular region is a segment which is a plurality of virtual regions arranged along the circumferential CD by a plurality of second boundary lines BL2 extending in the radial RD. It is divided into SE. Each of the plurality of heater electrodes 500 is arranged in one of the plurality of segments SE set in the ceramic member 10. That is, in the electrostatic chuck 100 of the present embodiment, one heater electrode 500 is arranged in each of the plurality of segments SE.

FIG. 4 is an explanatory diagram schematically showing an XY cross-sectional configuration of one heater electrode 500 arranged in one segment SE. As shown in FIG. 4, the heater electrode 500 has a heater line portion 510 which is a linear resistance heating element when viewed in the Z-axis direction, and a heater pad portion (first heater) connected to both ends of the heater line portion 510. It has a pad portion 521 and a second heater pad portion 522). Hereinafter, the first heater pad portion 521 and the second heater pad portion 522 are collectively referred to as heater pad portions 521 and 522. In the Z-axis direction, the width of the heater pad portions 521 and 522 is larger than the width of the heater line portion 510. The same applies to the configuration of the heater electrodes 500 arranged in the other segment SE.

Further, as shown in FIG. 2, the electrostatic chuck 100 has a configuration for supplying power to each heater electrode 500 constituting the heater electrode layer 50. Specifically, the electrostatic chuck 100 includes a driver electrode 60. The driver electrode 60 is made of a conductive material (for example, tungsten, molybdenum, platinum, etc.). The driver electrode 60 has a plurality of conductive regions 61 and 62 which are patterns having predetermined regions parallel to the plane direction. In this embodiment, the driver electrode 60 is arranged below the heater electrode layer 50. The driver electrode 60 differs from the heater electrode 500 in that it satisfies at least one of the following (1) and (2).
(1) The cross-sectional area of the driver electrode 60 is 10 times or more the cross-sectional area of the heater electrode 500.
(2) In the plane direction, the driver electrode 60 has a larger area than one segment SE.

All or part of the plurality of heater electrodes 500 constituting the heater electrode layer 50 are connected in parallel to the pair of conductive regions 61 and 62 in the driver electrode 60. Specifically, as shown in FIGS. 2 and 4, the first heater pad portion 521 of each heater electrode 500 is a driver electrode 60 via a first heater side via 721 formed of a conductive material. The second heater pad portion 522 of each heater electrode 500 is connected to the first conductive region 61, which is one of the pair of conductive regions 61 and 62 in the above. It conducts through the via 722 to the second conductive region 62 which is the other of the pair of conductive regions 61 and 62 in the driver electrode 60. Hereinafter, the first heater side via 721 and the second heater side via 722 are also collectively referred to as a heater side via 721 and 722.

Further, as shown in FIG. 2, the electrostatic chuck 100 is formed with a pair of terminal holes 110, 120 extending from the lower surface S4 of the base member 20 to the inside of the ceramic member 10. The terminal holes 110 and 120 have a through hole 22 that penetrates the base member 20 in the vertical direction, a through hole 32 that penetrates the adhesive layer 30 in the vertical direction, and a recess 12 formed on the lower surface S2 side of the ceramic member 10. Is an integral hole formed by communicating with each other.

A columnar first feeding terminal 741 is housed in the first terminal hole 110, which is one of the pair of terminal holes 110, 120. Further, a first electrode pad 731 is provided on the bottom surface of the recess 12 of the ceramic member 10 constituting the first terminal hole 110. The first power feeding terminal 741 is joined to the first electrode pad 731 by, for example, brazing or the like. Further, the first electrode pad 731 is conductive to the first conductive region 61 in the driver electrode 60 via the first feeding side via 711. The first feeding terminal 741, the first electrode pad 731, and the first feeding side via 711 are all made of a conductive material. Similarly, a columnar second feeding terminal 742 is housed in the second terminal hole 120, which is the other of the pair of terminal holes 110, 120. Further, a second electrode pad 732 is provided on the bottom surface of the recess 12 of the ceramic member 10 constituting the second terminal hole 120. The second feeding terminal 742 is joined to the second electrode pad 732 by, for example, brazing or the like. Further, the second electrode pad 732 is conductive to the second conductive region 62 in the driver electrode 60 via the second feeding side via 712.

In the following, the first power supply terminal 741 and the second power supply terminal 742 are collectively referred to as power supply terminals 741 and 742, and the first electrode pad 731 and the second electrode pad 732 are collectively referred to as the electrode pad 731. , 732, and the first feeding side via 711 and the second feeding side via 712 are collectively referred to as feeding side vias 711 and 712. The feeding terminals 741,742, the electrode pads 731,732, and the feeding side vias 711,712 are all made of a conductive material.

The pair of power feeding terminals 741 and 742 are connected to a power source (not shown). The voltage from the power supply is supplied to the pair of conductive regions 61 and 62 of the driver electrode 60 via the pair of feeding terminals 741,742, the pair of electrode pads 731,732, and the pair of feeding side vias 711 and 712. Further, it is applied to the heater electrode 500 via a pair of heater side vias 721 and 722 provided for each heater electrode 500. As a result, each heater electrode 500 generates heat, and the segment SE in which the heater electrode 500 is arranged is heated. By individually controlling the voltage applied to the heater electrodes 500 arranged in each segment SE of the ceramic member 10, the temperature of each segment SE can be individually controlled. As a result, control of the temperature distribution of the suction surface S1 of the ceramic member 10 (that is, control of the temperature distribution of the wafer W held on the suction surface S1) is realized.

A-3. Positional relationship between the power supply terminal and the heater pad:
5 and 6 are explanatory views showing the positional relationship between the power feeding terminal and the heater pad portion in the electrostatic chuck 100 of the present embodiment. FIG. 5 shows an XY cross-sectional configuration of a part of the periphery of the first heater pad portion 521 in one heater electrode 500, and the first heater via the first conductive region 61 of the driver electrode 60. The position of the first power feeding terminal 741 electrically connected to the pad portion 521 is indicated by a broken line. Further, FIG. 6 shows the XZ cross-sectional structure of the portion shown in FIG.

As shown in FIG. 5, in the following description, the connection portion between the first heater pad portion 521 and the heater line portion 510 is passed through the center point P0 of the first heater pad portion 521 in the Z-axis direction view. The virtual straight line parallel to the extending direction of the heater line portion 510 from the CP (in the present embodiment, approximately the positive direction of the X-axis) is referred to as a first virtual straight line VL1. Further, two virtual straight lines that pass through the center point P0 of the first heater pad portion 521 and have an angle of 45 degrees with the first virtual straight line VL1 are formed by the second virtual straight line VL2 and the third virtual straight line, respectively. It is called a straight line VL3.

If the center point P0 of the first heater pad portion 521 is not clear at first glance, a virtual circle VC that approximates the outer peripheral line of the first heater pad portion 521 is specified, and the center point of the virtual circle VC is specified. Is specified as the center point P0 of the first heater pad portion 521. If the extending direction of the heater line portion 510 from the connection portion CP between the first heater pad portion 521 and the heater line portion 510 is not clear at first glance, the virtual circle VC and the first heater pad portion Two intersections P1 and P2 with the outer peripheral line of 521 are specified, a midpoint P3 of a virtual line segment connecting the two intersections P1 and P2 is specified, and a midpoint P0 to a midpoint P3 of the first heater pad portion 521 is specified. The direction toward the heater line portion 510 is specified as the extension direction of the heater line portion 510.

In the present embodiment, in the Z-axis direction view, the first power feeding terminal 741 is the first heater pad portion 521 of the four regions separated by the second virtual straight line VL2 and the third virtual straight line VL3. It is located in the first region R1 facing the connection portion CP between the first heater pad portion 521 and the heater line portion 510 with the center point P0 in between. The fact that the first power supply terminal 741 is located in a certain area means that the center point P10 of the first power supply terminal 741 is located in the area.

Further, in the present embodiment, the first power feeding terminal 741 is located on the first virtual straight line VL1 in the Z-axis direction view. The fact that the first power supply terminal 741 is located on a certain virtual straight line means that at least a part of the first power supply terminal 741 overlaps the virtual straight line.

Further, in the present embodiment, when the above-mentioned first region R1 is divided into a first small region R11 and a second small region R12 by the first virtual straight line VL1 in the Z-axis direction view, the first region R1 The power feeding terminal 741 extends from the connection portion CP between the first heater pad portion 521 and the heater line portion 510 with respect to the first virtual straight line VL1 in the first small area R11 and the second small area R12. A small region (that is, FIG. 5) located in a direction opposite to the direction (in the present embodiment, the positive direction of the Y axis) in which the heater line portion 510 is separated from the first virtual straight line VL1 (the negative direction of the Y axis). In the example, it is located in the second small area R12).

Although the positional relationship between the first heater pad portion 521 of one heater electrode 500 and the feeding terminal has been described here, in the present embodiment, the first heater pad portions 521 and the second heater pad portion 521 of each heater electrode 500 have been described. The positional relationship between the heater pad portion 522 and the power feeding terminal is the same.

A-4. Effect of this embodiment:
As described above, the electrostatic chuck 100 of the first embodiment includes a ceramic member 10 having a substantially planar suction surface S1 substantially perpendicular to the Z-axis direction, and an object is placed on the suction surface S1 of the ceramic member 10. A holding device for holding (for example, a wafer W). The electrostatic chuck 100 includes a plurality of heater electrodes 500 arranged inside the ceramic member 10. Each heater electrode 500 is connected to a heater line portion 510 which is a linear resistance heating element in the Z-axis direction and an end portion of the heater line portion 510, and is wider than the heater line portion 510 in the Z-axis direction. It has a large heater pad portion 521,522. Further, the electrostatic chuck 100 is arranged inside the ceramic member 10, and includes a driver electrode 60 including conductive regions 61 and 62, a feeding terminal 741,742, and a conductive region 61 of the feeding terminals 741 and 742 and the driver electrode 60. Heat supply side vias 711 and 712 that electrically connect 62, and heater side vias 721 and 722 that electrically connect the heater pad portions 521 and 522 of each heater electrode 500 and the conductive regions 61 and 62 of the driver electrode 60. And. Further, in the electrostatic chuck 100 of the present embodiment, in the Z-axis direction view, it passes through the center point P0 of the heater pad portions 521 and 522, and from the connection portion CP between the heater pad portions 521 and 522 and the heater line portion 510. The virtual straight line parallel to the stretching direction of the heater line portion 510 is defined as the first virtual straight line VL1, and the two virtual straight lines passing through the center point P0 and having an angle of 45 degrees with the first virtual straight line VL1 are respectively. When the second virtual straight line VL2 and the third virtual straight line VL3 are used, the power supply terminals 741 and 742 are the center points of the four regions separated by the second virtual straight line VL2 and the third virtual straight line VL3. It is located in the first region R1 facing the connection portion CP with P0 in between. Since the electrostatic chuck 100 of the present embodiment has such a configuration, the controllability of the temperature distribution of the suction surface S1 of the ceramic member 10 (and by extension, the temperature distribution of the wafer W) is as described below. Controllability) can be improved.

In each heater electrode 500, the heater pad portions 521 and 522 have a larger width than the heater line portion 510 in the Z-axis direction. Therefore, the calorific value of the heater pad portions 521 and 522 is the calorific value of the heater line portion 510. Very little compared to. Therefore, in the suction surface S1 of the ceramic member 10, the region overlapping the heater pad portions 521 and 522 and the side opposite to the extending direction of the heater line portion 510 with respect to the heater pad portions 521 and 522 in the Z-axis direction. The region overlapping the regions (hereinafter referred to as “specific region Rx”) tends to be a low temperature temperature singularity. When a low-temperature temperature singularity is generated on the suction surface S1 of the ceramic member 10, the controllability of the temperature distribution of the suction surface S1 is lowered, and eventually the controllability of the temperature distribution of the wafer W is lowered.

However, as described above, in the electrostatic chuck 100 of the present embodiment, the feeding terminals 741 and 742 are the heater pad portion of the four regions separated by the second virtual straight line VL2 and the third virtual straight line VL3. It is located in the first region R1 facing the connection portion CP between the heater pad portion 521 and 522 and the heater line portion 510 with the center point P0 of 521 and 522 interposed therebetween (see FIG. 5). The first region R1 is a region that includes most of the specific region Rx that tends to be the above-mentioned low temperature temperature singularity. Therefore, in the conductive regions 61 and 62 of the driver electrode 60, the current I1 (FIG. 6) is located in the vicinity of the straight line connecting the heater pad portions 521 and 522 and the feeding terminals 741 and 742 located in the first region R1 in the Z-axis direction. 5 and FIG. 6) can prevent the above-mentioned specific region Rx from becoming a low-temperature temperature singular point due to the heat generated by the flow. Therefore, according to the electrostatic chuck 100 of the present embodiment, it is possible to suppress the generation of a low temperature temperature singularity on the suction surface S1 of the ceramic member 10, and control the temperature distribution of the suction surface S1 of the ceramic member 10. The property (and by extension, the controllability of the temperature distribution of the wafer W) can be improved. The high controllability of the temperature distribution of the suction surface S1 of the ceramic member 10 means that the temperature distribution of the entire suction surface S1 is close to uniform and that the temperature distribution of the suction surface S1 is close to uniform for each segment SE. Includes at least one of the meanings of.

Further, as described above, in the electrostatic chuck 100 of the present embodiment, the feeding terminals 741 and 742 are located on the first virtual straight line VL1 in the Z-axis direction view. At the position on the first virtual straight line VL1 in the above-mentioned specific region Rx, it tends to be a temperature singularity at a particularly low temperature. According to the electrostatic chuck 100 of the present embodiment, in the conductive regions 61 and 62 of the driver electrode 60, the heater pad portions 521 and 522 and the feeding terminals 741 located on the first virtual straight line VL1 in the Z-axis direction are viewed. It is possible to effectively suppress the specific region Rx from becoming a low temperature singular point due to heat generated by the current I1 flowing in the vicinity of the straight line connecting the 742, and the temperature distribution of the adsorption surface S1 of the ceramic member 10 can be effectively suppressed. Controllability (and thus controllability of the temperature distribution of the wafer W) can be effectively improved.

Further, as described above, in the electrostatic chuck 100 of the present embodiment, in the Z-axis direction view, the above-mentioned first region R1 is converted into a first small region R11 and a second small region by the first virtual straight line VL1. When divided into R12, the power supply terminals 741 and 742 have a heater pad portion 521 and 522 and a heater line portion 510 with respect to the first virtual straight line VL1 in the first small area R11 and the second small area R12. The heater line portion 510 extending from the connection portion CP with the above is located in a small region (second small region R12) located in a direction opposite to the direction away from the first virtual straight line VL1. In the above-mentioned specific region Rx, in the small region (second small region R12) where the heater line portion 510 extended from the connection portion CP is located in the direction opposite to the direction away from the first virtual straight line VL1. In particular, it tends to be a low temperature singularity. According to the electrostatic chuck 100 of the present embodiment, in the conductive regions 61 and 62 of the driver electrode 60, the heater pad portions 521 and 522 in the Z-axis direction and the feeding terminals 741 located in the second small region R12. It is possible to effectively suppress that the specific region Rx becomes a low temperature singular point due to heat generated by the current I1 flowing in the vicinity of the straight line connecting the 742, and the temperature distribution of the adsorption surface S1 of the ceramic member 10 can be effectively suppressed. Controllability (and thus controllability of the temperature distribution of the wafer W) can be effectively improved.

B. Second embodiment:
FIG. 7 is an explanatory diagram showing the positional relationship between the power feeding terminal and the heater pad portion in the electrostatic chuck 100 of the second embodiment. In the following, among the configurations of the electrostatic chuck 100 of the second embodiment, the same configurations as the configurations of the electrostatic chuck 100 of the first embodiment described above will be appropriately omitted by adding the same reference numerals. ..

As shown in FIG. 7, the electrostatic chuck 100 of the second embodiment has a different configuration of the heater line portion 510 of the heater electrode 500 as compared with the electrostatic chuck 100 of the first embodiment. Specifically, in the electrostatic chuck 100 of the second embodiment, the portion between the first power feeding terminal 741 and the first heater pad portion 521 in the first virtual straight line VL1 is formed in the Z-axis direction. The portion that overlaps with the heater line portion 510 and overlaps with the first virtual straight line VL1 in the heater line portion 510 (hereinafter referred to as “overlapping portion 510a”) overlaps with the first virtual straight line VL1 in the heater line portion 510. Wider than at least part of it. The overlapping portion 510a does not have to be a part of the heater line portion 510 that constitutes the common heater electrode 500 with the first heater pad portion 521, and even if it is a heater line portion 510 that constitutes a different heater electrode 500. good.

Although the configuration of the heater line portion 510 has been described here with respect to the first heater pad portion 521 side of one heater electrode 500, in the present embodiment, the first heater pad portion 521 side of each heater electrode 500 and the first heater pad portion 521 side and The heater line portion 510 has the same configuration on both sides of the second heater pad portion 522.

In addition to the heat generated from the overlapping portion 510a, the position of the overlapping portion 510a of the heater line portion 510 is such that the first heater pad portion 521 and the first heater pad portion 521 in the first conductive region 61 of the driver electrode 60 are viewed in the Z-axis direction. Since heat is generated by the current I1 flowing in the vicinity of the straight line connecting the power supply terminal 741, it tends to be a high temperature singular point. In the electrostatic chuck 100 of the second embodiment, the overlapping portion 510a overlapping with the first virtual straight line VL1 in the heater line portion 510 is compared with at least a part not overlapping with the first virtual straight line VL1 in the heater line portion 510. And the diameter is large. Therefore, the calorific value of the overlapping portion 510a in the heater line portion 510 is smaller than the calorific value of the other portions in the heater line portion 510. Therefore, according to the electrostatic chuck 100 of the second embodiment, it is possible to suppress the generation of a high temperature temperature singularity on the suction surface S1 of the ceramic member 10, and the temperature distribution of the suction surface S1 of the ceramic member 10 can be suppressed. Controllability (and thus controllability of the temperature distribution of the wafer W) can be effectively improved.

C. Third embodiment:
FIG. 8 is an explanatory diagram showing the configuration of the driver electrode 60 in the electrostatic chuck 100 of the third embodiment. In the following, among the configurations of the electrostatic chuck 100 of the third embodiment, the same configurations as the configurations of the electrostatic chuck 100 of the first embodiment described above will be appropriately omitted by adding the same reference numerals. ..

As shown in FIG. 8, the electrostatic chuck 100 of the third embodiment has a different configuration of the driver electrode 60 as compared with the electrostatic chuck 100 of the first embodiment. Specifically, in the electrostatic chuck 100 of the third embodiment, the first conductive region 61 of the driver electrode 60 has a plurality of heater electrodes 500 (see FIG. 2) via the first heater side via 721 (see FIG. 2). It is connected to the first heater pad portion 521 (first heater pad portion 521A, 521B, 521C) of the heater electrodes 500A, 500B, 500C).

Further, in the electrostatic chuck 100 of the third embodiment, the shape of the conductive region 61 of the driver electrode 60 overlaps with the first heater pad portion 521 of one heater electrode 500 and other heaters in the Z-axis direction. The shape has a notch between the electrode 500 and the region overlapping the first heater pad portion 521. That is, the virtual line segments VLS1 and VLS2 connecting the center point of the first heater pad portion 521 of one heater electrode 500 and the center point of the first heater pad portion 521 of the other heater electrode 500 in the Z-axis direction. Passes through a region other than the first conductive region 61.

Although the configuration of one conductive region 61 of the driver electrode 60 has been described here, in the present embodiment, each conductive region of the driver electrode 60 has the same configuration.

As described above, in the electrostatic chuck 100 of the third embodiment, the virtual center point of the heater pad portions 521 and 522 of one heater electrode 500 and the center point of the heater pad portions 521 and 522 of the other heater electrode 500 are connected. Since the line segments VLS1 and VLS2 are configured to pass through regions other than the conductive regions 61 and 62, the heater pad portions 521 and 522 and the feeding terminals in the conductive regions 61 and 62 of the driver electrode 60 in the Z-axis direction are viewed. The path of the current I1 flowing between the 741 and 742 can be a path close to a straight line connecting the heater pad portions 521 and 522 and the feeding terminals 741 and 742. Therefore, according to the electrostatic chuck 100 of the third embodiment, the current flowing between the heater pad portions 521,522 and the feeding terminals 741,742 in the conductive regions 61 and 62 of the driver electrode 60 in the Z-axis direction. It is possible to effectively suppress the specific region Rx from becoming a low temperature singular point due to the heat generated by I1, and the controllability of the temperature distribution of the suction surface S1 of the ceramic member 10 (and thus the control of the temperature distribution of the wafer W). Sex) can be effectively improved.

D. Modification example:
The technique disclosed in the present specification is not limited to the above-described embodiment, and can be transformed into various forms without departing from the gist thereof, and for example, the following modifications are also possible.

The configuration of the electrostatic chuck 100 in the above embodiment is merely an example and can be variously modified. For example, the electrostatic chuck 100 of the above embodiment is
(1) In the Z-axis direction, the heater line portion 510 passes through the center point P0 of the heater pad portions 521 and 522, and the heater line portion 510 is extended from the connection portion CP between the heater pad portion 521 and 522 and the heater line portion 510. The parallel virtual straight line is defined as the first virtual straight line VL1, and the two virtual straight lines passing through the center point P0 and having an angle of 45 degrees with the first virtual straight line VL1 are the second virtual straight line VL2 and the third virtual straight line, respectively. When the virtual straight line VL3 of the above is used, the power supply terminals 741 and 742 are connected to the connection portion CP with the center point P0 in the four regions separated by the second virtual straight line VL2 and the third virtual straight line VL3. The condition that it is located in the opposite first region R1 and
(2) The condition that the feeding terminals 741 and 742 are located on the first virtual straight line VL1 in the Z-axis direction is satisfied.
(3) When the first region R1 is divided into the first small region R11 and the second small region R12 by the first virtual straight line VL1 in the Z-axis direction view, the power supply terminals 741 and 742 are the first. Of the small region R11 and the second small region R12, the heater line portion 510 extended from the connection portion CP between the heater pad portions 521 and 522 and the heater line portion 510 is the first with respect to the first virtual straight line VL1. The condition that it is located in a small area (second small area R12) located in the direction opposite to the direction away from the virtual straight line VL1 and
However, if at least condition (1) is satisfied among the above three conditions, at least one of condition (2) and condition (3) may not be satisfied. Even with such a configuration, it is possible to suppress the generation of low-temperature temperature singularities on the suction surface S1 of the ceramic member 10, and the controllability of the temperature distribution of the suction surface S1 of the ceramic member 10 (and by extension, the wafer). The controllability of the temperature distribution of W) can be improved.

In the electrostatic chuck 100 of the above embodiment, the above conditions (1) to (3) are satisfied with respect to the positional relationship between the first heater pad portion 521 and the second heater pad portion 522 of each heater electrode 500 and the feeding terminal. However, the above conditions (1) to (3) (or at least condition (1)) are satisfied with respect to the positional relationship between at least one heater pad portion of at least one heater electrode 500 and the feeding terminal. Just do it. With such a configuration, it is possible to suppress the generation of a low-temperature temperature singularity on the suction surface S1 of the ceramic member 10 at a location where the above conditions are satisfied, and the temperature distribution of the suction surface S1 of the ceramic member 10 can be suppressed. Controllability (and thus controllability of the temperature distribution of the wafer W) can be improved.

Similarly, in the electrostatic chuck 100 of the second embodiment, the heater line portion 510 is the specific one described above for both the first heater pad portion 521 side and the second heater pad portion 522 side of each heater electrode 500. Although it has a configuration, the heater line portion 510 may have the above-mentioned specific configuration for at least one heater pad portion side of at least one heater electrode 500. Further, in the electrostatic chuck 100 of the third embodiment, each conductive region of the driver electrode 60 has the above-mentioned specific configuration, but at least one conductive region may have the above-mentioned specific configuration. ..

Further, in the above embodiment, each via may be composed of a single via or a group of a plurality of vias. Further, in the above embodiment, each via may have a single-layer configuration consisting of only a via portion, or may have a multi-layer configuration (for example, a configuration in which a via portion, a pad portion, and a via portion are laminated). May be good.

Further, the setting mode of the segment SE in the above embodiment can be arbitrarily changed. For example, in the above embodiment, a plurality of segment SEs are set so that the segment SEs are arranged in the circumferential direction CD of the suction surface S1, but a plurality of segment SEs are set so that the segment SEs are arranged in a grid pattern. May be done. Further, for example, in the above embodiment, the entire electrostatic chuck 100 is virtually divided into a plurality of segment SEs, but even if a part of the electrostatic chuck 100 is virtually divided into a plurality of segment SEs. good. Further, in the electrostatic chuck 100, the segment SE does not necessarily have to be set.

Further, in the above embodiment, a unipolar method in which one chuck electrode 40 is provided inside the ceramic member 10 is adopted, but a bipolar method in which a pair of chuck electrodes 40 are provided inside the ceramic member 10 is adopted. It may be adopted. Further, the material forming each member in the electrostatic chuck 100 of the above embodiment is merely an example, and each member may be formed of another material.

Further, the present invention is not limited to the electrostatic chuck 100 which includes the ceramic member 10 and the base member 20 and holds the wafer W by utilizing electrostatic attraction, but also includes the ceramic member and an object on the surface of the ceramic member. It can also be applied to other holding devices (for example, a heater device such as a CVD heater, a vacuum chuck, etc.).

10: Ceramics member 12: Recessed portion 20: Base member 21: Refrigerant flow path 22: Through hole 30: Adhesive layer 32: Through hole 40: Chuck electrode 50: Heater electrode layer 60: Driver electrode 61: First conductive region 62: Second conductive region 100: Electrostatic chuck 110: First terminal hole 120: Second terminal hole 500: Heater electrode 510: Heater line part 510a: Overlapping part 521: First heater pad part 522: First 2 heater pad part 711: 1st feeding side via 712: 2nd feeding side via 721: 1st heater side via 722: 2nd heater side via 731: 1st electrode pad 732: 2nd electrode Pad 741: First power supply terminal 742: Second power supply terminal

Claims (5)

A ceramic member having a substantially planar first surface substantially perpendicular to the first direction,
A plurality of heater electrodes arranged inside the ceramic member, each connected to a heater line portion which is a linear resistance heating element in the first directional view and an end portion of the heater line portion. In addition, a plurality of heater electrodes having a heater pad portion having a width larger than that of the heater line portion in the first directional view, and a plurality of heater electrodes.
A driver electrode arranged inside the ceramic member and including a conductive region,
Power supply terminal and
A feeding side via that electrically connects the feeding terminal and the conductive region of the driver electrode,
A heater-side via that electrically connects the heater pad portion of each heater electrode and the conductive region of the driver electrode, and
In a holding device for holding an object on the first surface of the ceramic member.
In the first directional view, a virtual straight line that passes through the center point of the heater pad portion and is parallel to the extending direction of the heater line portion from the connection portion between the heater pad portion and the heater line portion is first. When the two virtual straight lines passing through the center point and forming an angle of 45 degrees with the first virtual straight line are used as the second and third virtual straight lines, respectively, the power feeding terminal is the above. A holding device, characterized in that it is located in a first region facing the connection portion with the center point sandwiched between the four regions separated by the second and third virtual straight lines. In the holding device according to claim 1,
The holding device, characterized in that, in the first directional view, the feeding terminal is located on the first virtual straight line. In the holding device according to claim 1 or 2.
When the first region is divided into first and second small regions by the first virtual straight line in the first directional view, the feeding terminal is included in the first and second small regions. The heater line portion extending from the connection portion is located in the small region located in the direction opposite to the direction away from the first virtual straight line with respect to the first virtual straight line. A characteristic holding device. In the holding device according to any one of claims 1 to 3.
In the first directional view, the portion between the power feeding terminal and the heater pad portion in the first virtual straight line overlaps with the heater line portion, and the first virtual straight line in the heater line portion. The holding device is characterized in that the portion overlapping with the heater line portion is wider than at least a portion of the heater line portion that does not overlap with the first virtual straight line. In the holding device according to any one of claims 1 to 4.
The conductive region is connected to the heater pad portions of the plurality of heater electrodes via the heater side vias, and in the first directional view, the center point of one heater pad portion and the other heater pad portions. A holding device characterized in that a virtual line segment connecting a center point of a heater pad portion passes through a region other than the conductive region.

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