JP2020194800A - Holding device - Google Patents

Abstract

To increase the resistance of a heater electrode while the controllability of the temperature distribution on the surface of a plate-shaped member is improved and an increase in thickness of the plate-shaped member is suppressed.SOLUTION: A holding device includes a plate-shaped member, and a main heater electrode arranged in each main segment when the plate-shaped member is divided into a plurality of main segments. The holding device includes a driver electrode and a sub-heater electrode arranged in each sub-segment when each main segment is divided into a plurality of sub-segments. The plurality of sub-heater electrodes constituting a sub-heater electrode group which is a set of the sub-heater electrodes arranged in each sub-segment belonging to one main segment are in a parallel relationship with each other. The sub-heater electrode group arranged in one main segment is connected in series with the main heater electrode arranged in the one main segment via the driver electrode.SELECTED DRAWING: Figure 4

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 formed of, for example, a plate-shaped member formed of ceramics and having a surface (hereinafter referred to as “adsorption surface”) substantially orthogonal to a predetermined direction (hereinafter referred to as “first direction”) and a plate-shaped member. A chuck electrode is provided inside the member, and the wafer is sucked and held on the suction surface of the plate-shaped 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, a heater electrode is provided inside the plate-shaped member, and the temperature distribution of the suction surface of the plate-shaped member is controlled (by extension, the temperature distribution of the wafer held on the suction surface is controlled) by heating by the heater electrode. .. The heater electrode is composed of a resistance heating element extending in a direction substantially orthogonal to the first direction (hereinafter, referred to as "plane direction").

In the electrostatic chuck, in order to improve the controllability of the temperature distribution on the suction surface, at least a part of the plate-shaped member is divided into a plurality of virtual parts (hereinafter, referred to as “segments”) arranged in the surface direction. A configuration in which heater electrodes are arranged in each segment may be adopted. According to such a configuration, the temperature of each segment can be individually controlled by individually controlling the voltage applied to the heater electrodes arranged in each segment of the plate-shaped member, and as a result, the suction surface of the suction surface can be controlled individually. The controllability of the temperature distribution can be improved. In recent years, in order to control the temperature of the adsorption surface with higher accuracy, there is an increasing demand for an increase in the number of segment divisions, and for example, a form of dividing into 200 or more segments is also being studied.

Here, in order to pass an amount of current required for use as an electrostatic chuck to the heater electrode, it is necessary to secure a cross-sectional area of a predetermined value or more as the cross-sectional area of the heater electrode. Therefore, the cross-sectional area of the heater electrode Is difficult to make smaller than necessary. Further, when the number of segments in the electrostatic chuck is increased, the area of each segment in the first directional view becomes smaller, so that it is difficult to extend the wire length of the heater electrode. Therefore, the resistance value of the heater electrodes arranged in each segment cannot be sufficiently increased. If the resistance value of each heater electrode is low when a predetermined voltage is applied, the current value flowing through each heater electrode becomes large in order to obtain the desired wattage, and it is necessary to increase the size of the power supply, cable, etc. Therefore, it is not preferable.

Conventionally, in each segment, a plurality of resistance heating elements having different positions in the first direction are connected in series to form one heater electrode, whereby the resistance value of the heater electrodes arranged in each segment can be determined. A technique for increasing the height is known (see, for example, Patent Document 1).

International Publication No. 2018/143288

As described above, in the electrostatic chuck, when the number of segment divisions is increased in order to control the temperature of the suction surface with higher accuracy, the area of each segment in the first directional view becomes smaller. Therefore, in the above-mentioned conventional technique, in order to increase the resistance value of the heater electrodes arranged in each segment, a plurality of resistance heating elements constituting the heater electrodes (a plurality of resistance heating elements having different positions in the first direction). ) Needs to be increased, and therefore, it is necessary to increase the thickness of the plate-shaped member in the first direction. If the thickness of the plate-shaped member is increased, the heat mass becomes large and the ascending / descending temperature speed becomes slow, or the dielectric loss becomes large and the plasma escape becomes poor, which is not preferable.

It should be noted that such a problem is not limited to the electrostatic chuck that holds the wafer by utilizing electrostatic attraction, and includes a plate-shaped member and heater electrodes arranged in each segment of the plate-shaped member, and has a plate-like shape. A holding device that holds an object on the surface of a member is a common problem in general.

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

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

(1) The holding device disclosed in the present specification is a plate-shaped member having a first surface substantially orthogonal to the first direction, and at least a part of the plate-shaped member is orthogonal to the first direction. A main heater electrode, which is arranged in each of the main segments when virtually divided into a plurality of main segments arranged in a direction and is composed of a resistance heating element, is provided, and is provided on the first surface of the plate-shaped member. In the holding device for holding the object, the subheaters arranged in each of the subsegments when each main segment is virtually divided into a plurality of subsegments arranged in a direction orthogonal to the first direction. An electrode, a driver electrode provided for each of the main heater electrodes and electrically connected to the main heater electrode, and a driver electrode provided for each of the main heater electrodes and electrically connected to the driver electrode of the main heater electrode. A first terminal member electrically connected to the end on the opposite side to the end on the side, and a side provided for each of the sub-heater electrodes and electrically connected to the driver electrode in the sub-heater electrode. It is a set of the subheater electrodes arranged in each subsegment belonging to one main segment, including a second terminal member electrically connected to an end opposite to the end. The plurality of sub-heater electrodes constituting the sub-heater electrode group are in a parallel relationship with each other, and the sub-heater electrode group arranged in one main segment is contained in the one main segment via the driver electrode. It is connected in series with the arranged main heater electrode.

In this holding device, each main segment is virtually divided into a plurality of sub-segments, and each sub-segment is provided with sub-heater electrodes electrically connected to a second terminal member and having a parallel relationship with each other. There is. Therefore, by individually controlling the power supply to each sub-heater electrode, it is possible to realize finer temperature control in sub-segment units as compared with temperature control in main segment units, and the first plate-shaped member can be controlled. The controllability of the surface temperature distribution can be improved.

Further, in this holding device, the sub-heater electrode group is connected in series with the main heater electrode. Therefore, as compared with the configuration in which the holding device has only the main heater electrode (1 layer) or the holding device has only the sub heater electrode (1 layer), the space between the first terminal member and the second terminal member The resistance of the heater electrode can be increased. Therefore, according to this holding device, when a predetermined voltage is applied, a desired wattage can be obtained without increasing the current value flowing through each heater electrode, that is, without increasing the size of the power supply, cable, or the like. Can be done.

Further, in this holding device, since each main segment is virtually divided into a plurality of sub-segments in a direction orthogonal to the first direction, the main segment is compared with the sub-segment in the first directional view. The area is large. Therefore, it is easily feasible to increase the resistance of the main heater electrodes arranged in the main segment. Therefore, according to this holding device, as compared with the case where a plurality of resistance heating elements having different positions in the first direction for each sub-segment are connected in series to form one heater electrode, a plate-shaped member is used. It is possible to suppress the increase in the thickness of the.

From the above, according to the present holding device, the controllability of the temperature distribution on the first surface of the plate-shaped member is controlled by realizing the temperature control in the subsegment unit, which is finer than the temperature control in the main segment unit. The thickness of the plate-shaped member is increased as compared with the case where a plurality of resistance heating elements having different positions in the first direction are connected in series in each subsegment to form one heater electrode. The first terminal member and the second terminal can be made thinner than the configuration in which the holding device has only the main heater electrode (1 layer) or the holding device has only the sub heater electrode (1 layer). The resistance of the heater electrode between the member and the member can be increased.

(2) In the holding device, the plurality of sub-heater electrodes constituting the sub-heater electrode group arranged in the one main segment are resistors constituting the main heater electrode arranged in the one main segment. It may be configured by a resistance heating element having a resistance lower than that of the heating element. According to this holding device, the resistance of the heater electrode between the first terminal member and the second terminal member can be effectively increased.

(3) In the holding device, the amount of heat generated per unit area of each of the subheater electrodes arranged in each of the subsegments belonging to the main segment in the first direction is substantially the same as each other. It may be configured. According to this holding device, highly accurate temperature control can be realized in units of sub-segments, and the controllability of the temperature distribution on the first surface of the plate-shaped member can be effectively improved.

(4) In the holding device, each of the main heater electrodes is arranged at a first position in the first direction, and each of the sub heater electrodes is located in the first direction from the first position. It may be configured to be arranged at a second position close to the first surface. According to this holding device, the sub-heater electrodes arranged in the more subdivided sub-segments are arranged closer to the first surface than the main heater electrodes arranged in the main segment as compared with the main segment. By controlling the temperature in units of sub-segments by switching the power supply to the sub-heater electrodes, the controllability of the temperature distribution on the first surface of the plate-shaped member can be further effectively improved.

(5) In the holding device, each of the main heater electrodes is arranged at a first position in the first direction, and each of the sub-heater electrodes is located at the first position in the first direction. The driver electrodes may be arranged at different second positions, and each of the driver electrodes may be arranged at a third position different from the first position and the second position in the first direction. According to this holding device, the degree of freedom in pattern setting of the driver electrode is improved as compared with the configuration in which the driver electrode is arranged at the same position as the main heater electrode or the sub heater electrode in the first direction. , The degree of freedom in pattern setting of the main heater electrode and the sub heater electrode is also improved. Therefore, according to this holding device, more suitable patterns of the main heater electrode and the sub-heater electrode can be realized, so that the controllability of the temperature distribution on the first surface of the plate-shaped member can be further effectively improved.

The technique disclosed in the present specification can be realized in various forms, for example, a holding device, an electrostatic chuck, a vacuum chuck, a manufacturing method thereof, and the like. is there.

Perspective view schematically showing the appearance configuration of the electrostatic chuck 100 in this embodiment. Explanatory drawing schematically showing the XZ cross-sectional structure of the electrostatic chuck 100 in this embodiment. Explanatory drawing schematically showing the XY plane configuration of the electrostatic chuck 100 in this embodiment. Explanatory drawing schematically showing the structure of the main heater electrode layer 60, the sub-heater electrode layer 50, the driver electrode layer 70, and the like. Explanatory drawing schematically showing the XY cross-sectional structure of one main heater electrode 600 arranged in one main segment MSE. Explanatory drawing schematically showing the XY cross-sectional structure of the subheater electrode 500 arranged in each of the four subsegments SSE set in one main segment MSE. Explanatory drawing schematically showing the XY cross-sectional structure of one driver electrode 700 provided for one main segment MSE.

A. This embodiment:
A-1. Configuration of electrostatic chuck 100:
FIG. 1 is a perspective view schematically showing an external configuration of the electrostatic chuck 100 in the present embodiment, and FIG. 2 is an explanatory view schematically showing an XZ cross-sectional configuration of the electrostatic chuck 100 in the present embodiment. FIG. 3 is an explanatory view schematically showing the XY plane (upper surface) configuration of the electrostatic chuck 100 in the present 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 a direction. 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 example, for fixing a wafer W in a vacuum chamber of a semiconductor manufacturing apparatus. The electrostatic chuck 100 includes a plate-shaped 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 plate-shaped member 10 and the base member 20 are arranged so that the lower surface S2 (see FIG. 2) of the plate-shaped member 10 and the upper surface S3 of the base member 20 face each other in the arrangement direction with the joint portion 30 described later interposed therebetween. Will be done. That is, the base member 20 is arranged so that the upper surface S3 of the base member 20 is located on the lower surface S2 side of the plate-shaped member 10.

The plate-shaped member 10 is a plate-shaped member having a substantially circular surface (hereinafter, referred to as “adsorption surface”) S1 substantially orthogonal to the above-mentioned arrangement direction (Z-axis direction), and is, for example, ceramics (for example, alumina or It is made of aluminum nitride, etc.). The diameter of the plate-shaped member 10 is, for example, about 50 mm to 500 mm (usually about 200 mm to 350 mm), and the thickness of the plate-shaped member 10 is, for example, about 1 mm to 10 mm, preferably about 2 mm to 8 mm, and further. It is preferably about 3 mm to 6 mm. The suction surface S1 of the plate-shaped 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 CP of the suction surface S1 is "plane direction". It is called "circumferential CD", and the direction orthogonal to the circumferential CD in the plane direction is called "radial RD".

As shown in FIG. 2, a chuck electrode 40 formed of a conductive material (for example, tungsten, molybdenum, platinum, etc.) is arranged inside the plate-shaped 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 chuck power supply (not shown), an electrostatic attraction is generated, and the wafer W is attracted and fixed to the suction surface S1 of the plate-shaped member 10 by this electrostatic attraction.

Further, as shown in FIG. 2, inside the plate-shaped member 10, a main heater electrode layer 60, a sub-heater electrode layer 50, and a driver, which are formed of conductive materials (for example, tungsten, molybdenum, platinum, etc.), respectively. The electrode layer 70 and the electrode layer 70 are arranged. The main heater electrode layer 60, the sub-heater electrode layer 50, and the driver electrode layer 70 are layers of conductive materials that spread in the plane direction, respectively. In the Z-axis direction (vertical direction), the positions of the main heater electrode layer 60, the sub-heater electrode layer 50, and the driver electrode layer 70 are different from each other. Specifically, in the Z-axis direction, the sub-heater electrode layer 50 is arranged at a position below the chuck electrode 40 and above the main heater electrode layer 60 (the side close to the suction surface S1). Further, the driver electrode layer 70 is arranged at a position between the sub-heater electrode layer 50 and the main heater electrode layer 60 in the Z-axis direction. In the Z-axis direction, the position where the main heater electrode layer 60 is arranged corresponds to the first position in the claims, and the position where the sub-heater electrode layer 50 is arranged corresponds to the second position in the claims. However, the position where the driver electrode layer 70 is arranged corresponds to the third position in the claims. These configurations will be described in detail later.

The base member 20 is, for example, a circular flat plate-shaped member having the same diameter as the plate-shaped member 10 or having a diameter larger than that of the plate-shaped 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 plate-shaped member 10 by a joint portion 30 arranged between the lower surface S2 of the plate-shaped member 10 and the upper surface S3 of the base member 20. The joint portion 30 is made of an adhesive material such as a silicone resin, an acrylic resin, or an epoxy resin. The thickness of the joint portion 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 is transferred between the base member 20 and the plate-shaped member 10 via the joint portion 30. The plate-shaped member 10 is cooled by (heat transfer), and the wafer W held on the suction surface S1 of the plate-shaped member 10 is cooled. As a result, control of the temperature distribution of the wafer W is realized.

A-2. Configuration of main heater electrode layer 60, sub-heater electrode layer 50, driver electrode layer 70, etc .:
Next, the configurations of the main heater electrode layer 60, the sub-heater electrode layer 50, the driver electrode layer 70, and the like arranged on the plate-shaped member 10 will be described in detail. FIG. 4 is an explanatory diagram schematically showing the configurations of the main heater electrode layer 60, the sub-heater electrode layer 50, the driver electrode layer 70, and the like. FIG. 4 schematically shows the configurations of the main heater electrode layer 60, the sub-heater electrode layer 50, the driver electrode layer 70, and the like arranged in a part of the plate-shaped member 10.

Here, as shown in FIG. 3, in the electrostatic chuck 100 of the present embodiment, the main segment MSE, which is a plurality of virtual parts arranged in the plane direction (direction orthogonal to the Z-axis direction) on the plate-shaped member 10. (Indicated by a alternate long and short dash line in FIG. 3) is set. More specifically, in the Z-axis direction, the plate-shaped member 10 has a plurality of virtual annular portions (provided that the plate-shaped member 10 is formed by a plurality of concentric first boundary lines BL1 centered on the center point CP of the suction surface S1. Only the part including the center point CP is divided into circular parts), and each annular part is a plurality of virtual parts arranged in the circumferential direction CD by a plurality of second boundary lines BL2 extending in the radial direction RD. It is divided into main segments MSE. The number of main segment MSEs is, for example, about 200 to 250.

As shown in FIG. 4, the main heater electrode layer 60 includes a plurality of main heater electrodes 600. Each of the plurality of main heater electrodes 600 included in the main heater electrode layer 60 is arranged in one of the plurality of main segment MSEs set in the plate-shaped member 10. That is, in the electrostatic chuck 100 of the present embodiment, one main heater electrode 600 is arranged in each of the plurality of main segment MSEs. In other words, in the plate-shaped member 10, the portion where one main heater electrode 600 is arranged (mainly the portion heated by the main heater electrode 600) becomes one main segment MSE. The boundary line between two main segment MSEs adjacent to each other in the radial or circumferential direction in the Z-axis direction is a main heater electrode 600 arranged in one main segment MSE and a main heater electrode arranged in the other main segment MSE. It is a line at an intermediate position with 600.

FIG. 5 is an explanatory view schematically showing an XY cross-sectional configuration of one main heater electrode 600 arranged in one main segment MSE. In FIG. 5 (and FIG. 6 described later), the shape of the main segment MSE in the Z-axis direction is square for convenience, but it is actually the shape shown in FIG. As shown in FIG. 5, the main heater electrode 600 has a heater line portion 602 which is a linear resistance heating element in the Z-axis direction, and a heater pad portion 604 connected to both ends of the heater line portion 602. .. In the present embodiment, the heater line portion 602 is shaped so as to pass through each position in the main segment MSE as evenly as possible in the Z-axis direction. The configuration of the main heater electrode 600 arranged in the other main segment MSE is also the same.

Further, as shown in FIG. 4, in the electrostatic chuck 100 of the present embodiment, subsegment SSEs, which are a plurality of virtual portions arranged in the plane direction, are set in each main segment MSE of the plate-shaped member 10. .. More specifically, each main segment MSE of the plate-shaped member 10 is divided into sub-segments SSE which are a plurality of virtual portions having substantially the same shape in the Z-axis direction. The number of sub-segment SSEs set in each main segment MSE is, for example, four. That is, the number of sub-segments SSEs set in the entire plate-shaped member 10 is, for example, about 800 to 1,000 (= 200 to 250 × 4). As an example, FIG. 4 schematically shows a YZ cross-sectional configuration of four sub-segments SSE (SSE1 to SSE4) set in one main segment MSE.

As shown in FIG. 4, the sub-heater electrode layer 50 includes a plurality of sub-heater electrodes 500. Each of the plurality of sub-heater electrodes 500 included in the sub-heater electrode layer 50 is arranged in one of the plurality of sub-segment SSEs set in the plate-shaped member 10. That is, in the electrostatic chuck 100 of the present embodiment, one sub-heater electrode 500 is arranged in each of the plurality of sub-segments SSE. In other words, in the plate-shaped member 10, the portion where one sub-heater electrode 500 is arranged (mainly the portion heated by the sub-heater electrode 500) becomes one sub-segment SSE. The boundary line between two sub-segments SSEs adjacent to each other in the radial or circumferential direction in the Z-axis direction is a sub-heater electrode 500 arranged in one sub-segment SSE and a sub-heater electrode 500 arranged in the other sub-segment SSE. It is a line at the middle position of.

FIG. 6 is an explanatory diagram schematically showing an XY cross-sectional configuration of subheater electrodes 500 arranged in each of four subsegments SSE (SSE1 to SSE4) set in one main segment MSE. As shown in FIG. 6, each sub-heater electrode 500 has a heater line portion 502 which is a linear resistance heating element in the Z-axis direction, and a heater pad portion 504 connected to both ends of the heater line portion 502. .. The resistance of the resistance heating element constituting the sub-heater electrode 500 is lower than the resistance of the resistance heating element constituting the main heater electrode 600. In the present embodiment, the heater line portion 502 is shaped so as to pass through each position in the sub-segment SSE as evenly as possible in the Z-axis direction. It is preferable that the plurality of sub-segment SSEs belonging to the main segment MSE have substantially the same shape in the Z-axis direction because the design of the sub-heater electrodes 500 arranged in each sub-segment SSE can be shared. The same applies to the configuration of the sub-heater electrodes 500 arranged in each sub-segment SSE set in the other main segment MSE. In the following, the set of each sub-heater electrode 500 arranged in each sub-segment SSE belonging to one main segment MSE is referred to as a sub-heater electrode group 510. In the present embodiment, one sub-heater electrode group 510 is composed of four sub-heater electrodes 500.

Further, in the present embodiment, the amount of heat generated per unit area in the Z-axis direction of each sub-heater electrode 500 arranged in each sub-segment SSE belonging to one main segment MSE is substantially the same. In addition, in this specification, "the two values are substantially the same" means that the larger value of the two values is 110% or less of the smaller value.

In the present embodiment, as shown in FIG. 6, a part of the outer peripheral line of the sub-segment SSE coincides with a part of the outer peripheral line of the main segment MSE to which the sub-segment SSE belongs in the Z-axis direction. However, the two do not necessarily have to match. For example, a part of the outer peripheral line of the sub-segment SSE is located outside the outer peripheral line of the main segment MSE to which the sub-segment SSE belongs by a predetermined amount (however, so as not to exceed the outer peripheral line of the adjacent main segment MSE). You may be doing it. On the contrary, a part of the outer peripheral line of the sub-segment SSE may be located inside the outer peripheral line of the main segment MSE to which the sub-segment SSE belongs by the predetermined amount.

Further, as shown in FIG. 4, the driver electrode layer 70 arranged on the plate-shaped member 10 has a plurality of driver electrodes 700 extending in the plane direction. In this embodiment, one driver electrode 700 is provided for each of the plurality of main segment MSEs (plurality of main heater electrodes 600). FIG. 7 is an explanatory view schematically showing an XY cross-sectional configuration of one driver electrode 700 provided for one main segment MSE. The driver electrode 700 is a pattern of a conductive material formed so as to overlap the vias 81 and 83 described later in the Z-axis direction. The same applies to the configuration of the driver electrode 700 provided for the other main segment MSE.

As shown in FIGS. 4, 5 and 7, the driver electrode 700 provided for one main segment MSE is electrically connected to the main heater electrode 600 arranged for the one main segment MSE via the via 83. Has been done. Further, as shown in FIGS. 4, 6 and 7, each sub-heater electrode 500 arranged in each sub-segment SSE belonging to one main segment MSE (that is, a plurality (four) constituting one sub-heater electrode group 510). ) The sub-heater electrodes 500) are in a parallel relationship with each other. Further, the sub-heater electrode group 510 arranged in the one main segment MSE is connected in series with the main heater electrode 600 arranged in the one main segment MSE via the via 81, the driver electrode 700 and the via 83. It is connected.

Further, as shown in FIG. 2, a plurality of heater terminal holes Ht are formed in the electrostatic chuck 100. Each heater terminal hole Ht has a through hole that penetrates the base member 20 from the upper surface S3 to the lower surface S4, a through hole that penetrates the joint portion 30 in the vertical direction, and a recess formed on the lower surface S2 side of the plate-shaped member 10. Is an integral hole formed by communicating with each other. At the position corresponding to each heater terminal hole Ht on the lower surface S2 of the plate-shaped member 10 (the position overlapping the heater terminal hole Ht in the Z-axis direction), one or more heaters made of a conductive material are used. A power feeding pad 88 is formed. As shown in FIGS. 2 and 4, the heater feeding pad 88 is electrically connected to the end of the main heater electrode 600 via the via 84. Further, the other heater feeding pad 88 is electrically connected to the end of the sub-heater electrode 500 via the via 82.

Further, each heater terminal hole Ht accommodates one or a plurality of heater terminal members 89 made of a conductive material. Each heater terminal member 89 is joined to the heater power supply pad 88 by, for example, brazing. As a result, a certain heater terminal member 89 (hereinafter referred to as “first heater terminal member 89A”) is electrically connected to the driver electrode 700 in the main heater electrode 600 via the heater feeding pad 88 and the via 84. It is electrically connected to the end on the opposite side to the end on the side to which it is connected. Further, the other heater terminal member 89 (hereinafter, referred to as “second heater terminal member 89B”) is electrically connected to the driver electrode 700 in the sub-heater electrode 500 via the heater feeding pad 88 and the via 82. It is electrically connected to the end opposite to the end on the connected side.

In such a configuration, as shown in FIG. 4, from the first heater terminal member 89A, the heater feeding pad 88, via 84, main heater electrode 600, via 83, driver electrode 700, via 81, and sub-heater electrode 500 , Via 82 and the heater feeding pad 88, and an electric path EP reaching the second heater terminal member 89B is formed. In each main segment MSE, the electrical path EP is formed for each subsegment SSE (formed for each subheater electrode 500). That is, in the present embodiment, four electric paths EP are formed in each main segment MSE.

When a voltage is applied to the main heater electrode 600 and the sub-heater electrode 500 from a heater power source (not shown) via the electric path EP, the main heater electrode 600 and the sub-heater electrode 500 generate heat. The heat generated by the main heater electrode 600 heats the main segment MSE in which the main heater electrode 600 is arranged, and the heat generated by the sub heater electrode 500 heats the subsegment SSE in which the sub heater electrode 500 is arranged to attract the plate-shaped member 10. Control of the temperature distribution of the surface S1 (and thus control of the temperature distribution of the wafer W held on the suction surface S1 of the plate-shaped member 10) is realized.

In the present embodiment, since each main heater electrode 600 is connected to the heater power supply in parallel with each other, the calorific value of the main heater electrode 600 is generated in units of each main heater electrode 600 (that is, in units of each main segment MSE). It is possible to control the temperature distribution of the suction surface S1 of the plate-shaped member 10 in units of the main segment MSE. Further, in the present embodiment, since each subheater electrode 500 is in a parallel relationship with each other in each main segment MSE, the calorific value of the subheater electrode 500 is controlled in units of each subheater electrode 500 (that is, in units of each subsegment SSE). It is possible to control the temperature distribution of the suction surface S1 of the plate-shaped member 10 in the subsegment SSE unit (that is, control the temperature distribution in a finer unit that cannot be realized only by the main heater electrode 600). Can be done.

The amount of heat generated by each of the sub-heater electrodes 500 can be controlled by changing the ratio of the voltage application time for each of the sub-heater electrodes 500. For example, in the configuration shown in FIG. 4, when it is desired to lower the temperature of the sub-segment SSE4, the ratio of the voltage application time in the electric path EP passing through the sub-heater electrode 500 arranged in the sub-segment SSE4 may be lowered. Even if the ratio of the voltage application time in the electric path EP passing through the sub-heater electrode 500 arranged in the sub-segment SSE4 is set to zero, the main heater electrode 600 generates heat due to the voltage application in the electric path EP passing through the other sub-heater electrodes 500. Therefore, the temperature of the subsegment SSE4 does not drop significantly, and the temperature can be finely adjusted in units of the subsegment SSE.

A-3. Effect of this embodiment:
As described above, the electrostatic chuck 100 of the present embodiment has a plate-shaped member 10 having a suction surface S1 substantially orthogonal to the Z-axis direction, and a direction in which at least a part of the plate-shaped member 10 is orthogonal to the Z-axis direction. It is arranged in each main segment MSE when it is virtually divided into a plurality of main segment MSEs arranged in the (plane direction), includes a main heater electrode 600 composed of a resistance heating element, and a suction surface of the plate-shaped member 10. A device that holds an object (for example, a wafer W) on S1. Further, the electrostatic chuck 100 further describes the sub-heater electrodes 500 and the main heater electrodes 600 arranged in each sub-segment SSE when each main segment MSE is virtually divided into a plurality of sub-segment SSEs arranged in the plane direction. The driver electrode 700 is provided and is electrically connected to the main heater electrode 600 and the sub heater electrode 500. The electrostatic chuck 100 is further provided for each main heater electrode 600 and is electrically connected to an end of the main heater electrode 600 that is opposite to the end that is electrically connected to the driver electrode 700. The first heater terminal member 89A and each sub-heater electrode 500 are electrically connected to the end opposite to the end of the sub-heater electrode 500 that is electrically connected to the driver electrode 700. It is provided with a second heater terminal member 89B. Further, the sub-heater electrodes 500 constituting the sub-heater electrode group 510, which is a set of the sub-heater electrodes 500 arranged in each sub-segment SSE belonging to one main segment MSE, are in a parallel relationship with each other. Further, the sub-heater electrode group 510 arranged in the one main segment MSE is connected in series with the main heater electrode 600 arranged in the one main segment MSE via the driver electrode 700.

As described above, in the electrostatic chuck 100 of the present embodiment, each main segment MSE is virtually divided into a plurality of sub-segments SSEs, and each sub-segment SSE is electrically connected to the second heater terminal member 89B. Sub-heater electrodes 500 that are connected to each other and are in a parallel relationship are arranged. Therefore, by individually controlling the power supply to each sub-heater electrode 500, it is possible to realize finer temperature control in the sub-segment SSE unit as compared with the temperature control in the main segment MSE unit, and the plate-shaped member 10 can be realized. The controllability of the temperature distribution of the suction surface S1 of the above can be improved.

Further, in the electrostatic chuck 100 of the present embodiment, the sub-heater electrode group 510 is connected in series with the main heater electrode 600. Therefore, as compared with the configuration in which the electrostatic chuck 100 includes only the main heater electrode 600 (1 layer) and the configuration in which the electrostatic chuck 100 includes only the sub heater electrode 500 (1 layer), the first heater terminal member 89A The resistance of the heater electrode between the second heater terminal member 89B and the second heater terminal member 89B can be increased. Therefore, according to the electrostatic chuck 100, when a predetermined voltage is applied, a desired wattage can be obtained without increasing the current value flowing through each heater electrode, that is, without increasing the size of the power supply, cable, or the like. be able to.

The sub-heater electrode arranged in the sub-segment SSE is configured by connecting a plurality of resistance heating elements having different positions in the Z-axis direction in series to increase the resistance of the sub-heater electrode and flow to the sub-heater electrode. It is also conceivable to reduce the current value. However, since the area of the sub-segment SSE in the Z-axis direction is relatively small, it is difficult to increase the resistance value of each resistance heating element constituting the sub-heater electrode in such a configuration, and as a result, the resistance The thickness of the plate-shaped member 10 becomes thicker because the heating element needs to be multi-layered. If the thickness of the plate-shaped member 10 is increased, the heat mass becomes large and the ascending / descending temperature speed becomes slow, or the dielectric loss becomes large and the plasma escape becomes poor, which is not preferable.

On the other hand, in the electrostatic chuck 100 of the present embodiment, the resistance of the electric path EP is increased by connecting the main heater electrodes 600 arranged in the main segment MSE in series to the sub-heater electrode group 510. .. Since each main segment MSE is virtually divided into a plurality of sub-segment SSEs in a direction orthogonal to the Z-axis direction, the main segment MSE has a larger area in the Z-axis direction than the sub-segment SSE. Therefore, it is easily feasible to increase the resistance of the main heater electrode 600 arranged in the main segment MSE. Therefore, according to the electrostatic chuck 100 of the present embodiment, as compared with the case where a plurality of resistance heating elements having different positions in the Z-axis direction are connected in series in the sub-segment SSE unit to form one heater electrode. Therefore, it is possible to prevent the plate-shaped member 10 from becoming thicker.

As described above, according to the electrostatic chuck 100 of the present embodiment, the suction surface S1 of the plate-shaped member 10 is realized by realizing the temperature control in the subsegment SSE unit, which is finer than the temperature control in the main segment MSE unit. Compared with the case where a plurality of resistance heating elements having different positions in the Z-axis direction are connected in series in a subsegment SSE unit to form one heater electrode while improving the controllability of the temperature distribution of the plate. The thickness of the shape member 10 can be reduced, and compared with a configuration in which the electrostatic chuck 100 has only a main heater electrode (1 layer) or a configuration in which the electrostatic chuck 100 has only a sub heater electrode (1 layer). , The resistance of the heater electrode between the first heater terminal member 89A and the second heater terminal member 89B can be increased.

Further, in the electrostatic chuck 100 of the present embodiment, the sub-heater electrode 500 is composed of a resistance heating element having a lower resistance than the resistance heating element constituting the main heater electrode 600. Therefore, according to the electrostatic chuck 100 of the present embodiment, the resistance of the heater electrode between the first heater terminal member 89A and the second heater terminal member 89B can be effectively increased.

Further, in the electrostatic chuck 100 of the present embodiment, the amount of heat generated per unit area in the Z-axis direction of each sub-heater electrode 500 arranged in each sub-segment SSE belonging to one main segment MSE is substantially equal to each other. It is the same. Therefore, according to the electrostatic chuck 100 of the present embodiment, highly accurate temperature control can be realized in the sub-segment SSE unit, and the controllability of the temperature distribution of the suction surface S1 of the plate-shaped member 10 can be effectively controlled. Can be improved.

Further, in the electrostatic chuck 100 of the present embodiment, the sub-heater electrode layer 50 is arranged at a position above the position of the main heater electrode layer 60 (the side closer to the suction surface S1) in the Z-axis direction. That is, in the Z-axis direction, the sub-heater electrode 500 is arranged at a position above the position of the main heater electrode 600 (the side closer to the suction surface S1). As described above, in the electrostatic chuck 100 of the present embodiment, the subheater electrode 500 arranged in the subsegment SSE which is more subdivided as compared with the main segment MSE is the main heater electrode 600 arranged in the main segment MSE. Since it is arranged closer to the suction surface S1, the controllability of the temperature distribution of the suction surface S1 of the plate-shaped member 10 is further effective by controlling the temperature in units of the subsegment SSE by switching the power supply to the subheater electrode 500. Can be improved.

Further, in the electrostatic chuck 100 of the present embodiment, the positions of the main heater electrode layer 60, the sub-heater electrode layer 50, and the driver electrode layer 70 are different from each other in the Z-axis direction. That is, in the Z-axis direction, the positions of the main heater electrode 600, the sub-heater electrode 500, and the driver electrode 700 are different from each other. As described above, in the electrostatic chuck 100 of the present embodiment, the driver electrode 700 is arranged at a position different from the positions of the main heater electrode 600 and the sub heater electrode 500 in the Z-axis direction. Therefore, the degree of freedom in pattern setting of the driver electrode 700 is improved as compared with the configuration in which the driver electrode 700 is arranged at the same position as the main heater electrode 600 or the sub heater electrode 500 in the Z-axis direction. The degree of freedom in pattern setting of the heater electrode 600 and the sub-heater electrode 500 is also improved. Therefore, according to the electrostatic chuck 100 of the present embodiment, a more suitable pattern of the main heater electrode 600 and the sub-heater electrode 500 can be realized, so that the controllability of the temperature distribution of the suction surface S1 of the plate-shaped member 10 is more effective. Can be improved.

B. 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. 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 deformed. For example, in the above embodiment, the shapes of the main heater electrode 600 and the sub heater electrode 500 are merely examples, and can be deformed into any shape.

Further, the setting mode of the main segment MSE in the above embodiment (the number of main segment MSEs, the shape of each main segment MSE, etc.) can be arbitrarily changed. For example, in the above embodiment, a plurality of main segment MSEs are set so that the main segment MSEs are arranged in the circumferential direction CD of the suction surface S1, but a plurality of main segments MSEs are arranged in a grid pattern. The segment MSE may be set. Further, for example, in the above embodiment, the entire electrostatic chuck 100 is virtually divided into a plurality of main segment MSEs, but a part of the electrostatic chuck 100 is virtually divided into a plurality of main segment MSEs. You may.

Similarly, the setting mode of the sub-segment SSE in the above embodiment (the number of sub-segment SSEs per one main segment MSE, the shape of each sub-segment SSE, etc.) can be arbitrarily changed. For example, in the above embodiment, each main segment MSE is virtually divided into four sub-segment SSEs, but the number of divisions into sub-segment SSEs in each main segment MSE can be arbitrarily changed.

Further, in the above embodiment, the sub-heater electrode 500 is arranged above the main heater electrode 600 (the side closer to the suction surface S1) in the Z-axis direction, but the sub-heater electrode 500 is below the main heater electrode 600. It may be arranged (the side far from the suction surface S1). Further, in the above embodiment, the driver electrode 700 is arranged at a position different from the sub-heater electrode 500 and the main heater electrode 600 in the Z-axis direction, but the driver electrode 700 is the same as the sub-heater electrode 500 or the main heater electrode 600. It may be arranged at a position. Further, in the above embodiment, the sub-heater electrode 500 is composed of a resistance heating element having a lower resistance than the resistance heating element constituting the main heater electrode 600, but the relationship between the high and low resistance values of each resistance heating element is not necessarily such. It doesn't have to be a relationship.

Further, in the above embodiment, the via 82 extending downward from the sub-heater electrode 500 is directly connected to the second heater terminal member 89B, but between the via 82 and the second heater terminal member 89B. By arranging the driver electrode extending in the plane direction, the degree of freedom of the second heater terminal member 89B may be improved. Further, the second heater terminal member 89B may be collectively arranged in one heater terminal hole Ht in units of the main segment MSE, or the second heater terminal member 89B of the plurality of main segment MSEs may be arranged in one. It may be arranged in one heater terminal hole Ht.

Further, as described above, in the electrostatic chuck 100 of the present embodiment, if different voltages are applied to the terminal members 89B for each second heater, each sub-heater electrode 500 units (that is, each sub-segment SSE unit). However, if the same voltage is applied to each of the second heater terminal members 89B, the temperature distribution can be controlled in 600 units of each main heater electrode (that is, in each main segment MSE unit). It is possible to control the temperature distribution.

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, in the above embodiment, a unipolar method in which one chuck electrode 40 is provided inside the plate-shaped member 10 is adopted, but a bipolar system in which a pair of chuck electrodes 40 are provided inside the plate-shaped member 10 is adopted. The method may be adopted.

Further, the material for forming each member of the electrostatic chuck 100 of the above embodiment (plate-shaped member 10, base member 20, joint portion 30, sub-heater electrode layer 50, main heater electrode layer 60, driver electrode layer 70, etc.) is to the last. This is just an example and can be changed in various ways. For example, in the above embodiment, the electrostatic chuck 100 includes a plate-shaped member 10 formed of ceramics, but the electrostatic chuck 100 replaces the plate-shaped member 10 with a material other than ceramics (for example, resin). A similar plate-like member formed of the material) may be provided.

Further, the present invention is not limited to the electrostatic chuck 100 which includes the plate-shaped member 10 and the base member 20 and holds the wafer W by utilizing electrostatic attraction, but also in each segment of the plate-shaped member and the plate-shaped member. It is also applicable to other holding devices (for example, a heater device such as a CVD heater, a vacuum chuck, etc.) that hold an object on the surface of the plate-shaped member 10 by providing a heater electrode arranged in.

10: Plate-shaped member 20: Base member 21: Refrigerant flow path 30: Joint 40: Chuck electrode 50: Sub-heater electrode layer 60: Main heater electrode layer 70: Driver electrode layer 81: Via 82: Via 83: Via 84: Via 88: Power supply pad for heater 89: Terminal member for heater 100: Electrostatic chuck 500: Sub heater electrode 502: Heater line part 504: Heater pad part 600: Main heater electrode 602: Heater line part 604: Heater pad part 700: Driver electrode BL1: First boundary line BL2: Second boundary line CD: Circumferential direction CP: Center point EP: Electric path Ht: Heater terminal hole MSE: Main segment RD: Radial direction S1: Adsorption surface S2: Bottom surface S3: Top surface S4: Bottom surface SSE: Subsegment W: Wafer

Claims (5)

A plate-like member having a first surface that is substantially orthogonal to the first direction,
A main heater arranged in each of the main segments when at least a part of the plate-shaped member is virtually divided into a plurality of main segments arranged in a direction orthogonal to the first direction, and composed of a resistance heating element. With electrodes
Further, in a holding device for holding an object on the first surface of the plate-shaped member.
Sub-heater electrodes arranged in each of the sub-segments when each main segment is virtually divided into a plurality of sub-segments arranged in a direction orthogonal to the first direction.
A driver electrode provided for each of the main heater electrodes and electrically connected to the main heater electrode and the sub-heater electrode,
A first terminal member provided for each of the main heater electrodes and electrically connected to an end of the main heater electrode opposite to the end of the main heater electrode on the side electrically connected to the driver electrode.
A second terminal member provided for each of the sub-heater electrodes and electrically connected to an end of the sub-heater electrode opposite to the end on the side electrically connected to the driver electrode.
With
The plurality of sub-heater electrodes constituting the sub-heater electrode group, which is a set of the sub-heater electrodes arranged in each of the sub-segments belonging to one main segment, are in a parallel relationship with each other.
The sub-heater electrode group arranged in the one main segment is connected in series with the main heater electrode arranged in the one main segment via the driver electrode. Holding device. In the holding device according to claim 1,
The plurality of sub-heater electrodes constituting the sub-heater electrode group arranged in the one main segment have a resistance lower than that of the resistance heating element constituting the main heater electrode arranged in the one main segment. Consists of the body,
A holding device characterized by that. In the holding device according to claim 1 or 2.
The calorific value per unit area of each of the sub-heater electrodes arranged in each of the sub-segments belonging to the main segment in the first direction is substantially the same as each other.
A holding device characterized by that. In the holding device according to any one of claims 1 to 3.
Each of the main heater electrodes is arranged in a first position in the first direction.
Each of the sub-heater electrodes is arranged at a second position closer to the first surface than the first position in the first direction.
A holding device characterized by that. In the holding device according to any one of claims 1 to 4.
Each of the main heater electrodes is arranged in a first position in the first direction.
Each of the sub-heater electrodes is arranged in a second position different from the first position in the first direction.
Each of the driver electrodes is arranged in the first direction at a third position different from the first position and the second position.
A holding device characterized by that.

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