JP2017201669A - Heating member and electrostatic chuck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating member capable of easily performing temperature control, such as uniforming a temperature distribution of the heating member in a plane direction, and an electrostatic chuck.SOLUTION: An electrostatic chuck 1 has portions where a plurality of first heating elements 23 of a first heating portion 13 and a plurality of second heating elements 25 of a second heating portion 15 are arranged in a circumferential direction of a ceramic substrate 17, respectively, and moreover, the number of the first heating elements 23 is greater than that of the second heating elements 25. Therefore, temperatures of a ceramic heater 5 (accordingly the electrostatic chuck 1) in a plane direction can be easily uniformed, and moreover, temperatures at specific locations can be also easily controlled.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a heating member such as a ceramic heater that can heat a workpiece such as a semiconductor wafer, and an electrostatic chuck including the heating member.

  Conventionally, in a semiconductor manufacturing apparatus, a process such as dry etching (for example, plasma etching) is performed on a semiconductor wafer (for example, a silicon wafer). In order to increase the accuracy of this dry etching, it is necessary to securely fix the semiconductor wafer. As a fixing means for fixing the semiconductor wafer, an electrostatic chuck for fixing the semiconductor wafer by electrostatic attraction is used. Yes.

  Specifically, in an electrostatic chuck, for example, an adsorption electrode is provided in a ceramic substrate, and an electrostatic attractive force generated when a voltage is applied to the adsorption electrode is used to attach a semiconductor wafer to the ceramic substrate. Adsorb to the upper surface (mounting surface). In the electrostatic chuck, for example, a metal base is bonded to the lower surface (bonding surface) of the ceramic substrate.

  Some electrostatic chucks have a function of adjusting (heating or cooling) the temperature of the semiconductor wafer attracted to the attracting surface. For example, there is a technique of heating a semiconductor wafer on an adsorption surface by disposing a heating element in a ceramic substrate and heating the ceramic substrate with the heating element.

  Furthermore, in order to precisely heat the electrostatic chuck, a ceramic heater in which a ceramic substrate is divided into a plurality of heating zones has been developed. Specifically, a ceramic heater with a multi-zone heater has been proposed in which a heating element capable of independently heating each heating zone is arranged in each heating zone to improve the temperature adjustment function of the ceramic substrate ( Patent Document 1).

  Further, in recent years, a ceramic heater in which two layers of heating elements are arranged in the thickness direction inside the ceramic substrate has been developed for the purpose of adjusting the temperature more accurately with respect to the ceramic heater with a multi-zone heater. .

  In this two-layer type ceramic heater, a structure in which a sub-heater made of a heating element having a small heat generation amount is arranged on the mounting surface side and a main heater made of a heating element having a large heat generation amount is arranged on the opposite surface side can be considered.

JP 2005-166354 A

  However, in the above-described prior art, even when the ceramic heater is heated so that the temperature in the plane direction (in-plane temperature) is uniform, for example, due to some cause such as the structure of the etching apparatus, the ceramic heater is partially heated. Differences sometimes occurred. For example, in the planar direction of the ceramic heater, a portion having a low temperature may occur in the vicinity of the outer periphery thereof.

When a temperature difference occurs in the ceramic heater as described above, it is conceivable to control the sub heater so as to achieve a uniform temperature. However, the heat value of the sub heater is smaller than the heat value of the main heater (for example, 10 minutes). It is not easy to eliminate the temperature difference.

That is, even when the sub-heater is used, it is not easy to cope with the temperature change in the heated portion of the main heater.
The present invention has been made in view of the above problems, and an object thereof is to provide a heating member and an electrostatic chuck capable of easily performing temperature adjustment such as uniform temperature distribution in the planar direction of the heating member. There is.

  (1) A first aspect of the present invention includes an insulating substrate having a first main surface on which a workpiece is mounted and a second main surface opposite to the first main surface, and having electrical insulation. And a heat generating portion that is disposed on the insulating substrate and generates heat when energized. The heat generating portion includes a first heat generating portion disposed inside the insulating substrate and a second main surface side of the first heat generating portion. The heating member provided with the 2nd exothermic part arranged in.

  The heating member is a plan view of the insulating substrate as viewed from the thickness direction, and the first heat generating part and the second heat generating part are each composed of a plurality of heat generating elements capable of adjusting the temperature independently. A plurality of heat generating elements of the two heat generating parts are respectively arranged in the circumferential direction of the insulating substrate. In addition, the number of heating elements of the first heating part is larger than the number of heating elements of the second heating part.

  Thus, in the first aspect, the plurality of heating elements of the first heating unit and the second heating unit are arranged in the circumferential direction of the insulating substrate, respectively, and the number of heating elements of the first heating unit is Since it is larger than the number of heating elements of the second heating part, it is easy to make the temperature uniform in the plane direction of the heating member, and it is also easy to adjust the temperature at a specific location.

For example, the heat generation amount of the heating element of the second heat generating part can be increased (than the first heat generating part), and the entire temperature of the heating member can be made uniform quickly.
In addition, for example, even in a situation where the temperature of a part of the second heat generating part (for example, part of the outer peripheral part in the circumferential direction) decreases due to some cause such as the surrounding environment, the 2 By controlling the heating state of a part of the heating elements in the circumferential direction of the heating part (for example, a heating element having a larger heating amount than the heating element of the first heating part), the temperature of the region is raised, The entire temperature can be made uniform.

  In addition, the first heating unit uses more heating elements than the second heating unit, so that the temperature adjustment at a specific position (for example, a heating region narrower than the region where the temperature can be adjusted by the heating element of the second heating unit) is accurate. You can do it well.

  (2) In the second aspect of the present invention, the first heat generating portion includes a first annular portion disposed in each of a plurality of first annular regions concentrically divided in a plan view, and the first annular portion. Has a plurality of heating elements in the circumferential direction of the insulating substrate.

  The second heat generating portion has a second annular portion arranged in each of a plurality of second annular regions concentrically divided in a plan view, and the second annular portion has a plurality of circumferential directions of the insulating substrate. Has a heating element.

  The second aspect illustrates a preferable configuration of the heating member. With this configuration, the first heat generating portion and the second heat generating portion can easily adjust the temperature of the predetermined predetermined region in the radial direction and the circumferential direction.

  (3) According to a third aspect of the present invention, in a plan view, among the plurality of second annular regions, the second inner annular region including one second annular region on the inner peripheral side from the outermost periphery, and the plurality of first annular regions. The present invention relates to a first inner annular region composed of two or more first annular regions overlapping with a second inner annular region in the annular region.

  In the heating member, in the radial direction of the insulating substrate, the number of heating elements in the first inner annular region is greater than the number of heating elements in the second inner annular region, and in the circumferential direction of the insulating substrate, The number of heating elements in the first inner annular region is greater than the number of heating elements in the second inner annular region.

  In the third aspect, the number of heating elements in the first inner annular region is larger than the number of heating elements in the second inner annular region in both the radial direction and the circumferential direction. With many of the heating elements, the temperature can be accurately adjusted for each small area.

  In addition, since the number of heating elements in the second inner annular region is smaller than the number of heating elements in the first inner annular region in both the radial direction and the circumferential direction, the number of heating elements in the second heating unit is small. Therefore, there is an advantage that the number of wirings and terminals connected to the heating element can be reduced.

  (4) According to a fourth aspect of the present invention, in a plan view, the first outer annular region composed of one first annular region at the outermost periphery among the plurality of first annular regions and the first of the plurality of second annular regions. The present invention relates to a second outer annular region composed of two or more second annular regions overlapping one outer annular region.

  In the heating member, in the radial direction of the insulating substrate, the number of heating elements in the second outer annular region is equal to or greater than the number of heating elements in the first outer annular region, and in the circumferential direction of the insulating substrate, The number of heating elements in the first outer annular region is greater than the number of heating elements in the second outer annular region.

  In the fourth aspect, the number of heating elements in the second outer annular region is greater than or equal to the number of heating elements in the first outer annular region in the radial direction, and in the first outer annular region. Since the number of heating elements arranged in the circumferential direction is larger than the number of heating elements arranged in the second outer annular region, the temperature adjustment can be accurately performed for each small region by many heating elements in the first outer annular region. it can.

Moreover, when the number of heating elements arranged in the second outer annular region is larger than the number of heating elements arranged in the first outer annular region in the radial direction, temperature control of a smaller region can be performed. .
In particular, for example, by increasing the amount of heat generated by the second heat generating portion from that of the first heat generating portion, that is, by increasing the amount of heat generated by the heating element of the second heat generating portion disposed on the outermost periphery (than the first heat generating portion). The temperature of the outer peripheral portion of the insulating substrate can be easily adjusted.

  Since the outer peripheral portion (for example, the outermost periphery) of this insulating substrate is easily affected by the outside world, the temperature is likely to change. However, in this fourth aspect, even if there is such a large temperature change in the outer peripheral portion, the amount of heat generated Since many heat generating elements in the second outer annular region having a large amount are arranged in the radial direction, the temperature of the outer peripheral portion can be easily adjusted to a desired temperature.

(5) In the fifth aspect of the present invention, the heat generation amount per unit area of the second heat generating portion is larger than the heat generation amount per unit area of the first heat generating portion in plan view.
In the fifth aspect, since the heat generation amount per unit area of the second heat generating portion is larger than the heat generation amount per unit area of the first heat generating portion, the second heat generating portion causes the insulating substrate (and thus the heating member) to The temperature can be easily controlled to a desired temperature. For example, the temperature in the planar direction of the heating member can be easily made uniform.

It should be noted that the temperature of a predetermined region (region narrower than the second heat generating portion) in the plane direction of the heating member is accurately used by using the heating element of the first heat generating portion (a larger number than the second heat generating portion) having a small heat generation amount. Can be adjusted.

  (6) In the sixth aspect of the present invention, on the surface of the heating member, a first terminal portion that is electrically connected to the first heat generating portion and is supplied with electric power from the outside, and is electrically connected to the second heat generating portion. And a second terminal portion to which electric power is supplied from the outside. The second terminal portion is a terminal portion capable of supplying larger electric power than the first terminal portion.

  In the sixth aspect, by supplying larger electric power to the second terminal portion than the first terminal portion, the heat generation amount per unit area of the second heat generating portion is larger than the heat generation amount per unit area of the first heat generating portion. can do.

(7) A seventh aspect of the present invention is an electrostatic chuck including the heating member according to any one of the first to sixth aspects and having an electrostatic electrode on an insulating substrate.
In the seventh aspect, since the electrostatic chuck includes the heating member, the above-described temperature adjustment can be easily performed by the heating member.

In addition, as this invention, the following structure (a)-(d) is also employable.
(A) A heating member in which the first heat generating portion is disposed inside the insulating substrate and the second heat generating portion is disposed on the second main surface of the insulating substrate.

(B) A 2nd heat generating part is a heating member which consists of a several heat generating body arrange | positioned in a different position along the thickness direction of an insulated substrate.
(C) The insulating substrate is a heating member that is a ceramic substrate.

(D) A heating member in which a metal plate is bonded to the second main surface side of the insulating substrate.
<Each configuration of the present invention will be described below>
-The said main surface is the surface which makes the edge part in the thickness direction of a board | plate material (board | substrate).

An electrostatic electrode is an electrode that attracts a workpiece by electrostatic attraction generated by receiving electric power.
-A circumferential direction is a direction which surrounds the circumference | surroundings of the gravity center of a heating member by planar view. For example, in the case of a disk, it is a direction along the outer periphery (circumferential direction).

-A radial direction is a direction which goes to an outer periphery from the gravity center of a heating member by planar view. For example, for the annular regions arranged concentrically, the arrangement direction (that is, the arranged direction) is used.
The “terminal portion capable of supplying a large amount of power” is a terminal portion (that is, the second terminal portion) that is less likely to be damaged (compared to the first terminal portion) when the supplied power is increased.

  The heat generating portion includes first and second heat generating portions, and each heat generating portion includes first and second annular portions made of heat generating elements arranged in an annular shape (specifically concentric) in plan view. I have. Each annular region (that is, the first and second annular regions, the first and second inner annular regions, the first and second outer annular regions) has an annular shape corresponding to each annular region in plan view (specifically, This is a region divided so as to include heating elements arranged concentrically.

-Ceramics, resin, etc. can be adopted as the material of the insulating substrate.
Examples of the ceramic include a material mainly composed of aluminum oxide (alumina), aluminum nitride, zirconium oxide (zirconia), silicon carbide, or the like (50% by mass or more in the ceramic). In addition to the main component, for example, a rare earth compound may be added.

As the resin, polyimide, fluorine resin, or the like can be used.
The heating part (and hence the heating element) is a resistance heating element that generates heat when energized, and examples of the material of the heating element include tungsten, tungsten carbide, molybdenum, molybdenum carbide, tantalum, and platinum.

  -The terminal part is a conductive part (provided on the ceramic substrate) connected to the conductive part of the connector, which is an electrical connection member, and can adopt a configuration such as a pin or a pin hole into which the pin is inserted. .

  -Examples of the material of the electrostatic electrode include tungsten and molybdenum.

It is a perspective view showing a part of the electrostatic chuck of the first embodiment. It is sectional drawing which fractures | ruptures an electrostatic chuck in the thickness direction and shows the part typically. It is explanatory drawing which shows the arrangement | positioning in the planar direction of the heating zone of a 1st heat generating part, a heating area | region, and a 1st heat generating body. It is explanatory drawing which shows the arrangement | positioning in the planar direction of the heating zone of a 2nd heat generating part, a heating area | region, and a 2nd heat generating body. It is explanatory drawing (plan view) which piled up the 1st heat generating part and the 2nd heat generating part, and was seen from the thickness direction of the ceramic heater. It is explanatory drawing which overlaps a 1st heat generating part and a 2nd heat generating part, and distinguishes and shows the heating zone Z1 of an inner peripheral side, and the heating zone Z2 of an outermost periphery. (A) is explanatory drawing which shows a part of heating zone of the inner peripheral side of a 1st heat generating part and a 2nd heat generating part, (b) is the outer peripheral side of the heating zone of a 1st heat generating part among the heating zones of (a). Explanatory drawing which shows the state with high temperature of this, (c) is explanatory drawing which shows the temperature state at the time of overlapping a 1st heat generating part and a 2nd heat generating part. (A) is explanatory drawing which shows a part of heating zone of the outermost periphery of a 1st heat generating part and a 2nd heat generating part, (b) is a heating region of a part of 1st heat generating part among the heating zones of (a). Explanatory drawing which shows a state with high temperature, (c) is explanatory drawing which shows a temperature state at the time of overlapping a 1st heat generating part and a 2nd heat generating part. It is explanatory drawing which overlaps a 1st heat generating part and a 2nd heat generating part, and distinguishes and shows the heating zone Z1 of an inner peripheral side, and two heating zones Z2 of an outermost periphery. (A) is explanatory drawing which shows a part of heating zone of the outer peripheral side of a 1st heat generating part and a 2nd heat generating part, (b) is one of a 1st heat generating part and a 2nd heat generating part among the heating zones of (a). Explanatory drawing which shows the state with the high temperature of the range of a part, (c) is explanatory drawing which shows the temperature state at the time of overlapping a 1st heat generating part and a 2nd heat generating part. The modification of other embodiment is shown typically, (a) is sectional drawing which fractures | ruptures the electrostatic chuck of modification 1 in the thickness direction, (b) is the electrostatic chuck of modification 2 in the thickness direction FIG. 7C is a cross-sectional view showing the fracture of the electrostatic chuck of Modification 3 in the thickness direction, and FIG. 8D is a cross-sectional view of the ceramic heater of Modification 4 broken in the thickness direction. is there.

[1. First Embodiment]
Here, as the first embodiment, for example, an electrostatic chuck capable of attracting and holding a semiconductor wafer is taken as an example.
[1-1. Constitution]
First, the structure of the electrostatic chuck of the first embodiment will be described.

As shown in FIG. 1, the electrostatic chuck 1 of the first embodiment is a device that adsorbs a semiconductor wafer 3 that is a workpiece on the upper side of FIG. 1, and includes a ceramic heater (heating member) 5 and a metal base 7. Are laminated and bonded by the adhesive layer 9.

  The upper mounting surface (upper surface: adsorption surface) of the ceramic heater 5 in FIG. 1 is the first main surface A, and the lower surface is the second main surface B. Further, the upper surface of the metal base 7 is the third main surface C, and the lower surface is the fourth main surface D.

  Among these, the ceramic heater 5 has a disk shape and is composed of a ceramic substrate (insulating substrate) 17 provided with an adsorption electrode (electrostatic electrode) 11, a first heat generating portion 13, a second heat generating portion 15, and the like. . The adsorption electrode 11, the first heat generating part 13, and the second heat generating part 15 are embedded in the ceramic substrate 17.

  The metal base 7 has a disk shape larger in diameter than the ceramic heater 5 and is joined to the ceramic heater 5 coaxially. The metal base 7 is provided with a flow path (cooling path) 19 through which a cooling fluid (refrigerant) flows in order to cool the ceramic substrate 17 (and thus the semiconductor wafer 3). As the cooling fluid, for example, a cooling liquid such as a fluorinated liquid or pure water can be used.

  The electrostatic chuck 1 is provided with a plurality of lift pin holes 21 or the like into which lift pins (not shown) are inserted so as to penetrate the electrostatic chuck 1 in the thickness direction. The lift pin hole 21 is also used as a cooling gas flow path (cooling gas hole) supplied to the first main surface A side to cool the semiconductor wafer 3.

  In addition to the lift pin holes 21, a cooling gas hole (not shown) may be provided. As the cooling gas, for example, an inert gas such as helium gas or nitrogen gas can be used.

Next, each configuration of the electrostatic chuck 1 will be described in detail with reference to FIG.
<Ceramic heater>
As schematically shown in FIG. 2, the ceramic heater 5 (and hence the ceramic substrate 17) has a third main surface C of the metal base 7 on the second main surface B side by an adhesive layer 9 made of indium, for example. It is joined to the side.

  The ceramic substrate 17 is formed by laminating a plurality of ceramic layers (not shown), and is an alumina sintered body mainly composed of alumina. The alumina sintered body is an insulator (dielectric).

  Inside the ceramic substrate 17, as will be described in detail later from above in FIG. 2, a plurality of first heating elements 23 and second heating parts 15 constituting the adsorption electrode 11, the first heating part 13 are configured. A plurality of second heating elements 25 and the like are arranged.

  Among these, the adsorption electrode 11 is electrically connected to a known electrode terminal (not shown) for applying a voltage. The heating elements 23 and 25 are electrically connected to the power supply terminal 29 and the connector 31 via internal wiring and the like, which will be described later.

  Specifically, the first heating element 23 has one end of the first heating element 23 connected to the via 33 or the common internal wiring layer 35 and the other end connected to the via 33 or individual so that the temperature can be controlled independently. The internal wiring layer 37 is connected. The common internal wiring layer 35 and the individual internal wiring layer 37 are connected to each terminal 41 of the connector 31 via the first terminal portion 39 provided on the surface of the ceramic substrate 17 on the second main surface B side. It is connected.

The first terminal portion 39 is composed of a power supply pin 45 joined to the electrode pad 43, for example.
On the other hand, the second heating element 25 has one end of the second heating element 25 connected to the via 33 or the common internal wiring layer 47 and the other end connected to the via 33 or an individual so that the temperature can be controlled independently. It is connected to the internal wiring layer 49. The common internal wiring layer 47 and the individual internal wiring layer 49 are connected to the power feeding terminal 29 via the second terminal portion 51 provided on the surface of the ceramic substrate 17 on the second main surface B side. ing.

Note that the second terminal portion 51 includes, for example, a power feeding terminal 29 joined to the electrode pad 53.
Here, as will be described later, the amount of heat generated by the second heat generating portion 15 (and hence the second heat generating body 25) is larger than the amount of heat generated by the first heat generating portion 13 (and hence the first heat generating body 23). Since a larger current flows in the heating element 25 than in the first heating element 23, the second terminal portion 51 has a structure capable of supplying larger power than the first terminal portion 39 (that is, a structure having a large cross-sectional area perpendicular to the direction in which the current flows) ).

<Metal base>
The metal base 7 is made of metal made of aluminum or an aluminum alloy. In addition to the cooling path 19 and the lift pin hole 21, the metal base 7 is formed with a through portion 55 that is a through hole in which the electrode terminal, the power supply terminal 29, the connector 31 and the like are disposed.

  Note that an internal hole extending from the fourth main surface D to the inside of the ceramic heater 5 is provided on the fourth main surface D side of the electrostatic chuck 1 so as to accommodate the power supply terminal 29, the connector 31, and the like. A plurality of 57 are provided, and the penetrating portion 55 of the metal base 7 constitutes a part of the internal hole 57.

In addition, in the inner hole 57 that accommodates the electrode terminal and the power feeding terminal 29, an insulating cylinder 59 having electrical insulation is disposed so as to surround the outer periphery of each terminal 29.
The connector 31 is accommodated in the internal hole 57 (for the connector 31) as it is.

<Adsorption electrode>
The adsorption electrode 11 is composed of, for example, an electrode having a circular planar shape. When the electrostatic chuck 1 is used, a DC high voltage is applied to the adsorption electrode 11, thereby generating an electrostatic attractive force (adsorption force) for adsorbing the semiconductor wafer 3. It is used to adsorb and fix the semiconductor wafer 3. In addition to the above, various known configurations (monopolar or bipolar electrodes, etc.) can be employed for the adsorption electrode 11. The adsorption electrode 11 is made of a conductive material such as tungsten.
[1-2. First heating part and second heating part]
Next, the structure of the 1st heat generating part 13 and the 2nd heat generating part 15 is demonstrated.

  The second heat generating unit 15 is a main heater that generates a larger amount of heat than the first heat generating unit 13, and the first heat generating unit 13 is a sub-heater. Here, the large amount of heat generation is a comparison of the heat generation amounts of the first heat generation unit 13 and the second heat generation unit 15 as a whole, and the heat generation amount per unit area (in plan view) is also the second. The amount of heat generated by the second heating element 25 of the heating unit 15 is greater than the amount of heat generated by the first heating element 23 of the first heating unit 13.

The first and second heating elements 23 and 25 are resistance heating elements made of a metal material (such as tungsten) that generates heat when voltage is applied and current flows.
As shown in FIG. 2, each first heating element 23 of the first heating unit 13 is on the same plane (first plane H <b> 1) on the second main surface B side (downward in FIG. 2) from the adsorption electrode 11. (See FIG. 3).

On the other hand, each 2nd heat generating body 25 of the 2nd heat generating part 15 is arrange | positioned on the same plane (2nd plane H2: refer FIG. 4) between the 1st heat generating part 13 and the 2nd main surface B. FIG. ing.
Accordingly, the first heat generating portion 13 and the second heat generating portion 15 are arranged so as to be overlapped in a plan view as viewed from the thickness direction of the ceramic substrate 17 (and hence the electrostatic chuck 1). Details will be described below.

<First heating part>
First, the arrangement of the plurality of first heating elements 23 of the first heating unit 13 on the first plane H1 will be described.

  As shown in FIG. 3, the ceramic substrate 17 has a plurality of heating zones (first annular regions) 61 concentrically in plan view so that each region in the first plane H1 can be heated (accordingly, temperature adjustment). Is provided. In each heating zone 61, one or a plurality of heating regions 63 are set.

  Specifically, the heating zone 61 provided in the ceramic substrate 17 includes one circular first heating zone 61a including the axial center and an annular second heating that surrounds the outer periphery of the first heating zone 61a in a band shape. A zone 61b, an annular third heating zone 61c surrounding the outer peripheral side of the second heating zone 61b in a strip shape, an annular fourth heating zone 61d surrounding the outer peripheral side of the third heating zone 61c in a strip shape, and a fourth An annular fifth heating zone 61e surrounding the outer peripheral side of the heating zone 61d in a strip shape, an annular sixth heating zone 61f surrounding the outer peripheral side of the fifth heating zone 61e in a strip shape, and an outer peripheral side of the sixth heating zone 61f Is formed in an annular seventh heating zone 61g surrounding the belt.

That is, the heating zone 61 is composed of seven first to seventh heating zones 61a to 61g arranged concentrically.
The second heating zone 61b is divided into eight heating regions 63 so as to have the same central angle (equal pitch), and the third heating zone 61c is divided into eighteen heating regions 63 at an equal pitch, The fourth heating zone 61d is divided into 18 heating regions 63 at an equal pitch, the fifth heating zone 61e is divided into 30 heating regions 63 at an equal pitch, and the sixth heating zone 61f is arranged at an equal pitch. The seventh heating zone 61g is divided into 36 heating regions 63 at an equal pitch. Therefore, the shape of each heating region 63 is a circular or curved arc-shaped region having a predetermined width.

  One first heating element 23 is disposed in each of the first heating zone 61a (consisting of a single heating region 63) and each heating region 63 of the second to seventh heating zones 61b to 61g. Yes. In addition, the 1st annular part 24 is comprised by the some 1st heat generating body 23 for every 2nd-7th heating zones 61b-61g.

  Each first heating element 23 is composed of a long heating line, and is formed in, for example, a U shape in accordance with the shape of each heating region 63. Specifically, each first heating element 23 has a curved shape so as to follow the inner circumference and the outer circumference of each heating region 63, and is bent in a U shape at one end in the circumferential direction. In addition, the 1st heat generating body 23 of the 1st heating zone 61a is a circular (a part was notched) long elongate heating pattern according to the circular shape.

  In FIG. 3, the boundaries of the frame-shaped heating regions 63 are indicated by solid lines, and the first heating elements 23 arranged in the frames of the heating regions 63 are also indicated by solid lines. In addition, one heating element 23 is arranged in each heating region 63, but the shape (planar shape) of the first heating element 23 arranged in the circumferential direction in each of the heating zones 61b to 61g. Are the same, only a part is shown in FIG.

<Second heating part>
Next, the arrangement of the plurality of second heating elements 25 of the second heating unit 15 on the second plane H2 will be described.

  As shown in FIG. 4, the ceramic substrate 17 has a plurality of concentric heating zones (that is, second annular regions) in a plan view so that each region in the second plane H2 can be heated (accordingly, temperature adjustment). 71 is provided. In each heating zone 71, one or a plurality of heating regions 73 are set.

  Specifically, the heating zone 71 provided in the ceramic substrate 17 includes one circular first heating zone 71a including the axial center and an annular second heating that surrounds the outer periphery of the first heating zone 71a in a band shape. The zone 71b, an annular third heating zone 71c surrounding the outer periphery of the second heating zone 71b in a strip shape, and an annular fourth heating zone 71d surrounding the outer periphery of the third heating zone 71c in a strip shape. ing.

That is, the heating zone 71 is composed of four first to fourth heating zones 71a to 71d arranged concentrically.
The second heating zone 71b is divided into three heating regions 73 so as to have the same central angle (equal pitch), and the third heating zone 71c is divided into six heating regions 73 at equal pitches, The fourth heating zone 71d is divided into nine heating regions 73 at an equal pitch. Therefore, the shape of each heating region 73 is a circular or curved arc-shaped region having a predetermined width.

  One second heating element 25 is arranged in each of the first heating zone 71a, which is a single heating region 73, and the heating regions 73 of the second to fourth heating zones 71b to 71d. In addition, the 2nd annular part 26 is comprised by the several 2nd heat generating body 25 for every 2nd-4th heating zones 71b-71d.

  Each 2nd heat generating body 25 consists of an elongate heat generating line, and is formed in the U shape according to the shape of each heating area | region 73, for example. Specifically, each second heating element 25 has a curved shape so as to follow the inner circumference and the outer circumference of each heating region 73, and is bent in a U shape at one end in the circumferential direction. In addition, the 2nd heat generating body 25 of the 1st heating zone 71a is a circular (a part was notched) long elongate heat generating pattern according to circular shape.

In FIG. 4, the boundaries of the frame-shaped heating regions 73 are indicated by solid lines, and the second heating elements 25 disposed in the frames of the heating regions 73 are also indicated by solid lines. Further, one second heating element 25 is disposed in each heating region 73.
[1-3. Laminated structure of first heat generating part and second heat generating part]
Next, a configuration in which the first heat generating unit 13 and the second heat generating unit 15 are overlapped will be described.

  As shown in FIG. 5, the heating zone 61 corresponding to the first heat generating unit 13 and the heating zone 71 corresponding to the second heat generating unit 15 are arranged so as to overlap in plan view. In FIG. 5, a thin line indicates the boundary of the heating region 63 of the first heat generating unit 13, and a thick line indicates the boundary of the heating region 73 of the second heat generating unit 15 (note that the heating region 73 The boundary also serves as the boundary of the heating region 63).

That is, the first heating zone 61a and the second heating zone 61b of the first heat generating unit 13 and the first heating zone 71a of the second heat generating unit 15 completely overlap.
The 3rd heating zone 61c and the 4th heating zone 61d of the 1st exothermic part 13 and the 2nd heating zone 71b of the 2nd exothermic part 15 have overlapped completely.

  The fifth heating zone 61e and the sixth heating zone 61f (first inner annular region) of the first heating unit 13 and the third heating zone 71c (second inner annular region) of the second heating unit 15 completely overlap. ing.

The 7th heating zone 61g of the 1st exothermic part 13 and the 4th heating zone 71d of the 2nd exothermic part 15 have overlapped completely.
As can be seen from FIG. 5, the number of heating zones in the first heat generating section 13 (and hence the number of first heating elements 23) is equal to the number of heating zones in the second heat generating section 15 (and hence the number of second heating elements 25). Number) more.
[1-4. Temperature control of first heat generating part and second heat generating part]
In the first embodiment, different temperature control can be performed in the heating zone Z1 on the inner peripheral side and the heating zone Z2 on the outer peripheral side (that is, the outermost periphery) of the first heat generating unit 13 and the second heat generating unit 15. This temperature control will be described.

<Temperature control on the inner circumference>
Here, the inner heating zone Z1 is a heating zone inside the outermost heating zone Z2, as shown in the gray portion of FIG.

  Specifically, the heating zone Z1 on the inner peripheral side is the first to sixth heating zones 61a to 61f in the first heating unit 13, and the first to third heating zones 71a in the second heating unit 15. It is -71c.

  A part of the inner heating zone Z1 can be used. For example, in the case of the second heat generating part 15, at least one of the first to third heating zones 71a to 71c can be adopted.

Hereinafter, the temperature control of the heating zone Z1 on the inner peripheral side will be described in detail.
Here, for example, as shown in FIG. 7, an arbitrary heating zone that overlaps will be described as an example. In FIG. 7, a part of the overlapping heating zones is shown linearly.

  For example, as shown in FIG. 7A, the fifth heating zone 61e and the sixth heating zone 61f (which are the first inner annular region) of the first heat generating portion 13 and the (second inner annular shape) of the second heat generating portion 15 are provided. Consider a case where the third heating zone 71c (which is a region) overlaps.

  For example, as shown in FIG. 7B, when the temperature of the third heating zone 71 c of the second heat generating unit 15 is the same, the temperature of the sixth heating zone 61 f of the first heat generating unit 13 is the fifth. The power applied to the first heating element 23 is controlled so as to be higher than the temperature of the heating zone 61e. That is, temperature H> temperature L.

  As a result, as shown in FIG. 7C, the temperature of the portion corresponding to the sixth heating zone 61f of the first heat generating portion 13 is also the fifth in the overlapped region (and hence the planar direction of the ceramic heater 5). It becomes higher than the temperature of the part corresponding to the heating zone 61e.

Accordingly, it can be seen that in the heating zone Z1 on the inner peripheral side of the ceramic heater 5, the temperature can be finely controlled for each of the heating zones 61a to 61g of the first heat generating portion 13.
And
<Temperature control on the outer circumference>
Next, the temperature control of the heating zone Z2 on the outer peripheral side (that is, the outermost peripheral) shown in FIG.

  Here, as shown in FIG. 8A, the outermost heating zone Z2 is the seventh heating zone 61g in the first heating unit 13, and the fourth heating zone in the second heating unit 15. It is 71d.

  For example, as shown in FIG. 8B, when the temperature of the fourth heating zone 71d of the second heat generating unit 15 is the same, several heating regions 73 of the seventh heating zone 61g of the first heat generating unit 13 are provided. The power applied to the first heating element 23 is controlled so that the temperature of the hatched portion (FIG. 8B) is higher than the temperature of the other heating region 73. That is, temperature H> temperature L.

  As a result, as shown in FIG. 8C, even in the overlapped region, the temperatures of the portions corresponding to some heating regions 73 of the seventh heating zone 71g of the first heat generating unit 13 are in other heating regions. It becomes higher than the temperature of the part corresponding to 73.

Thereby, it can be seen that in the outermost heating zone Z <b> 2 of the ceramic heater 5, the temperature can be finely controlled for each heating region 73 of the first heat generating portion 13.
[1-5. Production method]
Next, a method for manufacturing the electrostatic chuck 1 of the first embodiment will be briefly described.

(1) As a raw material of the ceramic substrate 17, the main components of Al ₂ O ₃ : 92 wt%, MgO: 1 wt%, CaO: 1 wt%, and SiO ₂ : 6 wt% are mixed to form a ball mill. Then, after wet grinding for 50 to 80 hours, dehydrated and dried.

(2) Next, a solvent or the like is added to the powder and mixed with a ball mill to form a slurry.
(3) Next, this slurry is degassed under reduced pressure, and then poured into a flat plate shape and gradually cooled, and the solvent is diffused to form each alumina green sheet (corresponding to each ceramic layer).

Then, for each alumina green sheet, a space that becomes the lift pin hole 21 and the internal hole 57 and a through hole that becomes the via 33 are opened at a necessary place.
(4) Further, a tungsten powder is mixed in the raw material powder for the alumina green sheet to form a slurry to obtain a metallized ink.

  (5) Then, in order to form the adsorption electrode 11, each heating element 23, 25, each internal wiring layer 35, 37, 47, 49, etc., the adsorption electrode 11, each heating element is formed using the metallized ink. Each pattern is printed by an ordinary screen printing method on the alumina green sheet corresponding to the locations where the inner wiring layers 35, 37, 47, and 49 are formed. In order to form the via 33, the through hole is filled with metallized ink.

(6) Next, the alumina green sheets are aligned so that necessary spaces such as lift pin holes 21 are formed, and thermocompression-bonded to form a laminated sheet.
(7) Next, each thermocompression-bonded laminated sheet is cut into a predetermined shape (that is, a disc shape).

(8) Next, each cut laminated sheet is fired in a reducing atmosphere in the range of 1400 to 1600 ° C. (for example, 1550 ° C.) for 5 hours (main firing) to produce each alumina sintered body. .
(9) After firing, necessary processing such as processing on the first main surface A side is performed on each alumina sintered body to produce the ceramic substrate 17.

(10) Next, electrode pads 43 and 53 are formed on the necessary portions of the ceramic substrate 17.
(11) Next, for example, the pins 45 are brazed to the electrode pads 43. Further, the upper portion of the power supply terminal 29 is brazed to the electrode pad 53.

  (12) Separately, the metal base 7 is manufactured. Specifically, the metal base 7 provided with the internal holes 57 and the like is formed by cutting the metal plate. An insulating cylinder 59 is disposed in the internal hole 57.

(13) Next, the metal base 7 and the ceramic substrate 17 are joined and integrated.
(14) Next, the connector 31 and the power feeding terminal 29 are arranged corresponding to each internal hole 57 to complete the electrostatic chuck 1.
[1-6. effect]
Next, the effect of the first embodiment will be described.

  In the first embodiment, the first heating element 23 of the first heating unit 13 and the second heating element 25 of the second heating unit 15 each have a plurality of portions arranged in the circumferential direction of the ceramic substrate 17. In addition, the number of first heating elements 23 is larger than the number of second heating elements 25. Therefore, it is easy to make the temperature uniform in the plane direction of the ceramic heater 5 (and hence the electrostatic chuck 1), and it is also easy to adjust the temperature at a specific location.

Therefore, for example, the entire temperature of the ceramic heater 5 can be quickly made uniform by using the second heat generating portion 15 which is a main heater having a large heat generation amount.
In addition, for example, even in a situation where the temperature of a part of the second heat generating unit 15 (for example, part of the outer peripheral part in the circumferential direction) decreases due to some cause such as the surrounding environment, it is arranged in that area. By controlling the heat generation state of a part of the second heat generating element 25 in the circumferential direction of the second heat generating portion 15, the temperature of the region can be raised and the temperature of the entire ceramic heater 5 can be made uniform. .

  Furthermore, the first heat generating unit 13 uses more heat generating elements than the second heat generating unit 15, thereby accurately adjusting the temperature in a region narrower than the region where the temperature can be adjusted by the second heat generating unit 25 of the second heat generating unit 15. It can also be done.

  In the first embodiment, the first heat generating portion 13 includes the first annular portions 24 disposed in the plurality of heating zones 61 concentrically divided in a plan view, and the first annular portion 24 is a ceramic. A plurality of first heating elements 23 are provided in the circumferential direction of the substrate 17. Furthermore, the second heat generating portion 15 has a second annular portion 26 disposed in each of a plurality of heating zones 71 concentrically divided in a plan view, and the second annular portion 26 is in the circumferential direction of the ceramic substrate 17. A plurality of second heating elements 25 are provided.

  With this configuration, the first heat generating unit 13 and the second heat generating unit 15 can easily adjust the temperature of a predetermined predetermined region in the radial direction (that is, the radial direction) and the circumferential direction (that is, the circumferential direction). it can.

  In the first embodiment, the number of arrangement of the first heating elements 23 in the first inner annular regions (that is, the fifth and sixth heating zones of the first plane H1) 61e and 61f is the same in both the radial direction and the circumferential direction. Since the number of the second heating elements 25 in the second inner annular region (ie, the third heating zone of the second plane H2) 71c is larger than the number of the first heating elements 23 in the first inner annular regions 61e and 61f. Thus, the temperature can be accurately adjusted for each small area.

Further, the number of the second heating elements 25 in the second inner annular region 71c is smaller than the number of the first heating elements 23 in the first inner annular regions 61e and 61f in both the radial direction and the circumferential direction. There is an advantage that the number of the second heat generating elements 25 of the second heat generating part 15 can be suppressed, and therefore the number of wirings and terminals connected to the second heat generating elements 25 can be reduced.

  In the first embodiment, the heat generation amount per unit area of the second heat generating unit 15 (specifically, the second heat generating element 25) is the heat generation per unit area of the first heat generating unit 13 (specifically, the first heat generating element 23). Since it is larger than the amount, the temperature of the ceramic substrate 17 (and hence the ceramic heater 5) can be easily controlled to a desired temperature by the second heat generating part (15). For example, the temperature in the planar direction of the ceramic heater 5 can be easily made uniform.

  A predetermined region in the plane direction of the ceramic heater 5 (narrower than the second heat generating portion 15) is used by using the first heat generating body 23 of the first heat generating portion 13 having a smaller heat generation amount (more than the second heat generating portion 15). The temperature of the region can be adjusted with high accuracy.

In the first embodiment, by supplying larger electric power to the second terminal portion 51 than the first terminal portion 39, the amount of heat generated per unit area of the second heat generating portion 15 is reduced per unit area of the first heat generating portion 13. The calorific value can be made larger.
[2. Second Embodiment]
Next, the second embodiment will be described, but the description of the same contents as the first embodiment will be omitted or simplified. In addition, the same number is attached | subjected to the structure similar to 1st Embodiment.

The electrostatic chuck of the second embodiment has the same basic configuration as that of the electrostatic chuck of the first embodiment, but the configuration of the second heat generating portion overlapped with the first heat generating portion is different. Yes.
As shown in FIG. 9, in the second embodiment, as in the first embodiment, the first heat generating unit 13 is divided into first to seventh heating zones 61a to 61g and each heating zone 61a to 61g. Each 61g is divided into a plurality of heating regions 63 at a predetermined pitch.

  On the other hand, the second heat generating unit 15 includes first to third heating zones 71a to 71c as the inner heating zone Z1 (gray portion), and includes two heating zones as the outermost heating zone Z2. A fourth heating zone 71d is provided.

  That is, the fourth heating zone 71d is composed of an annular inner circumferential fourth inner heating zone 71d1 (which is a second outer annular region) and an outer annular annular fourth outer circumferential heating zone 71d2. Yes. The fourth heating zone 71d is an area overlapping with the seventh heating zone 61g (which is the first outer annular area) of the first heat generating unit 13.

Next, temperature control in the second embodiment will be described with reference to FIG.
In FIG. 10, a part of the overlapping heating zones is shown linearly.
As shown in FIG. 10A, the seventh heating zone 61g of the first heat generating part 13 overlaps the fourth inner peripheral heating zone 71d1 and the fourth outer peripheral heating zone 71d2 of the second heat generating part 15.

  Here, for example, as shown in FIG. 10 (b), the temperature of several heating regions 63 (hatched portions in FIG. 10 (b)) of the seventh heating zone 61g of the first heat generating part 13 is different from that of other heating. The power applied to the first heating element 23 is controlled so as to be higher than the temperature of the region 63. That is, temperature H> temperature L.

  In addition, the temperature is applied to the second heating element 25 so that the temperature of the fourth outer peripheral heating zone 71d2 (the hatched portion in FIG. 10B) of the second heat generating portion 15 is higher than the temperature of the fourth inner peripheral heating zone 71d1. To control the power. That is, temperature H> temperature L.

As a result, as shown in FIG. 10C, a region in which several heating regions 63 in the seventh heating zone 61 g of the first heat generating portion 13 having a high temperature overlap with the fourth outer peripheral heating zone 71 d 2 (FIG. 10C). The temperature at the portion where the hatching intersects in c) is the highest.

  Further, the temperature of a region where the several heating regions 63 of the seventh heating zone 61g of the first heat generating unit 13 having a high temperature overlap with the fourth inner peripheral heating zone 71d1 having a low temperature (hatched portion in FIG. 10C). Is next higher.

  And the area | region (the part which does not have hatching of FIG.10 (c)) where the other heating area | region 63 of the 7th heating zone 61g of the 1st heat generating part 13 with low temperature and the 4th inner peripheral heating zone 71d1 with low temperature overlap. Temperature is lowest.

Thus, it can be seen that in the outermost heating zone Z2 of the ceramic heater 5, the temperature on the inner peripheral side and the outer peripheral side can be finely controlled in a narrow width region.
As described above, the second embodiment has the same effects as those of the first embodiment.

  In the second embodiment, the heating zone 71 of the second heat generating unit 15 corresponding to the outermost seventh heating zone 61g of the first heat generating unit 13 includes the fourth inner peripheral heating zone 71d1 on the inner peripheral side and the outer peripheral side. As described above, in the outermost heating zone Z2 of the ceramic heater 5, the temperature on the inner peripheral side and the outer peripheral side of the ceramic heater 5 are divided into regions having a narrow width. Fine control is possible.

  For example, by increasing the amount of heat generation (per unit area) of the second heating element 25 of the fourth outer periphery heating zone 71d2 than the second heating element 25 of the fourth inner periphery heating zone 71d1, the outer peripheral portion of the ceramic heater 5 is increased. The temperature can be adjusted easily.

  Since the outer peripheral portion (for example, the outermost periphery) of the ceramic heater 5 is easily affected by the outside world, the temperature is likely to change. In the second embodiment, even if such a large temperature change occurs in the outer peripheral portion, Since the heating zone 71 including the second heating element 25 that generates a large amount of heat is subdivided in the radial direction, the temperature of the outermost peripheral portion can be easily adjusted to a desired temperature.

In addition, this invention is not limited to the said embodiment and experiment example at all, and it cannot be overemphasized that it can implement with a various aspect in the range which does not deviate from this invention.
(1) For example, in the said embodiment, although the 1st heat generating part 13 and the 2nd heat generating part 15 were arrange | positioned in the ceramic substrate 17, as FIG. The first heat generating part 13 may be arranged on the outside, and the second heat generating part 15 may be arranged outside the ceramic substrate 17 (that is, on the second main surface B side).

  (2) In the above embodiment, the first heat generating portion 13 and the second heat generating portion 15 are arranged in the thickness direction so as to overlap each other, but FIG. For example, the second heat generating portion 15 is configured by a plurality of layers arranged in the thickness direction (for example, two layers of an upper layer 15a on the first main surface A side and a lower layer 15b on the second main surface B side). May be.

  (3) Further, in each of the above embodiments, the electrostatic chuck 1 provided with the ceramic heater 5 and the metal base 7 is taken as an example. However, as shown in FIG. The present invention can also be applied to the electrostatic chuck 1 that does not include the metal base 7. That is, the present invention can also be applied to the electrostatic chuck 1 provided with the adsorption electrode 11, the first heat generating portion 13, and the second heat generating portion 15 in the ceramic heater 5.

  (4) In the above embodiments, the electrostatic chuck 1 including the ceramic heater 5 and the metal base 7 is taken as an example. However, the present invention can also be applied to a ceramic heater that is not an electrostatic chuck.

  For example, as shown in Modification 4 in FIG. 11 (d), a heating member including a first heat generating portion 13 and a second heat generating portion 15 similar to those of the above embodiments in an insulating substrate (for example, a ceramic substrate 17). (For example, it can be applied to a ceramic heater 5).

(5) Furthermore, the method of dividing the heating zone and the heating region is not limited to the above embodiment.
(6) In the first embodiment, two heating zones 61 (fifth) constituting the first inner annular region are compared with one heating zone 71 (third heating zone 71c) constituting the second inner annular region. Although the electrostatic chuck 1 in which the heating zone 61e and the sixth heating zone 61f) are completely overlapped is taken as an example, the present invention is different from the first heating zone 71 that constitutes the second inner annular region. Each of the two or more heating zones 61 constituting the inner annular region may partially overlap.

  (7) In the second embodiment, with respect to one heating zone 61 (seventh heating zone 61g) constituting the first outer annular region, two heating zones 71 (fourth fourth) constituting the second outer annular region. Although the electrostatic chuck 1 in which the inner peripheral heating zone 71d1 and the fourth outer peripheral heating zone 71d2) are completely overlapped is taken as an example, the present invention is directed to one heating zone 61 constituting the first outer annular region. Each of the two or more heating zones 71 constituting the second outer annular region may partially overlap.

(8) Various insulating substrates such as a ceramic substrate and a resin substrate can be adopted as the insulating substrate.
(9) The configurations of the embodiments can be combined as appropriate.

DESCRIPTION OF SYMBOLS 1 ... Electrostatic chuck 3 ... Semiconductor wafer 5 ... Ceramic heater 11 ... Electrostatic electrode 13 ... 1st heat generating part 15 ... 2nd heat generating part 17 ... Ceramic substrate 23 ... 1st heat generating body 25 ... 2nd heat generating body 61, 71 ... Heating zone 63, 73 ... heating area

Claims (7)

An insulating substrate having a first main surface on which a workpiece is mounted and a second main surface opposite to the first main surface, and having an electrical insulation, and an electric current disposed on the insulating substrate And a heat generating part that generates heat,
In the heating member provided with the 1st exothermic part arranged inside the insulating substrate as the exothermic part, and the 2nd exothermic part arranged on the 2nd principal surface side rather than the 1st exothermic part. ,
In a plan view of the insulating substrate viewed from the thickness direction,
The first heat generating part and the second heat generating part are each composed of a plurality of heat generating elements capable of adjusting the temperature independently,
The plurality of heating elements of the first heating part and the second heating part are respectively arranged in the circumferential direction of the insulating substrate,
The heating member is characterized in that the number of heating elements of the first heating part is larger than the number of heating elements of the second heating part. In the plan view,
The first heat generating portion includes first annular portions disposed in a plurality of first annular regions concentrically divided, and the first annular portion has a plurality of heating elements in a circumferential direction of the insulating substrate. Have
The second heat generating portion includes second annular portions disposed in a plurality of second annular regions concentrically divided, and the second annular portion generates a plurality of heat generation in the circumferential direction of the insulating substrate. The heating member according to claim 1, further comprising a body. In the plan view,
Of the plurality of second annular regions, a second inner annular region consisting of one second annular region on the inner peripheral side from the outermost periphery, and two of the plurality of first annular regions overlapping the second inner annular region. About a first inner annular region composed of two or more first annular regions,
In the radial direction of the insulating substrate, the number of the heating elements in the first inner annular region is greater than the number of the heating elements in the second inner annular region,
The number of the heating elements in the first inner annular region is greater than the number of the heating elements in the second inner annular region in the circumferential direction of the insulating substrate. The heating member as described. In the plan view,
Of the plurality of first annular regions, two or more of the first outer annular regions composed of the first annular region on the outermost periphery and the first outer annular region of the plurality of second annular regions overlap. For the second outer annular region comprising the second annular region,
In the radial direction of the insulating substrate, the number of the heating elements in the second outer annular region is greater than or equal to the number of the heating elements in the first outer annular region,
The number of the heating elements in the first outer annular region is greater than the number of the heating elements in the second outer annular region in the circumferential direction of the insulating substrate. 3. A heating member according to 3.   5. The heat generation amount per unit area of the second heat generating portion in the plan view is larger than the heat generation amount per unit area of the first heat generating portion. The heating member according to 1. On the surface of the heating member, a first terminal portion that is electrically connected to the first heat generating portion and supplied with power from the outside, and an electric power supply connected to the second heat generating portion and supplied from outside. A second terminal portion, and
The heating member according to any one of claims 1 to 5, wherein the second terminal portion is a terminal portion capable of supplying larger electric power than the first terminal portion.   An electrostatic chuck comprising the heating member according to claim 1, and an electrostatic electrode provided on the insulating substrate.