JP6530333B2 - Heating member and electrostatic chuck - Google Patents

Description

  The present invention relates to a heating member such as a ceramic heater capable of heating a workpiece such as a semiconductor wafer, for example, and an electrostatic chuck provided with the heating member.

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

  Specifically, in an electrostatic chuck, for example, a ceramic substrate is provided with a suction electrode, and a semiconductor wafer is made of a ceramic substrate using electrostatic attraction generated when a voltage is applied to the suction electrode. Adsorb to the upper surface (adsorption 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 adsorbed on the adsorption surface. For example, there is a technique in which a semiconductor wafer on the adsorption surface is heated by arranging a heating element in a ceramic substrate and heating the ceramic substrate by the heating element. Furthermore, there is also a technology in which a cooling path for flowing a cooling fluid is provided in the metal base, and the ceramic substrate is cooled by the cooling fluid.

  In recent years, ceramic heaters in which a ceramic substrate is divided into a plurality of heating zones (heating regions) have also been developed in order to precisely heat the electrostatic chuck. Specifically, a ceramic heater with multi-zone heater in which a heating element (partial heating element) capable of independently heating each heating zone is disposed in each heating zone to improve the temperature control function of the ceramic substrate is also possible. It is proposed (refer to patent documents 1 and 2).

As an electrostatic chuck (that is, a multi-zone electrostatic chuck) provided with this multi-zone heater and ceramic heater, for example, a structure shown in FIG. 10 can be considered.
Specifically, in electrostatic chuck P6 in which suction electrode P2 and a plurality of partial heating elements P3 are disposed on ceramic heater P1 and cooling path P5 is provided in metal base P4, each partial heating element P3 is provided. In order to measure the temperature in the vicinity of the center, through holes P7 are provided at positions overlapping the respective partial heating elements P3 in plan view with respect to the metal base P4, and thermocouples P8 are disposed in the respective through holes P7. .

  The through hole P7 is formed to penetrate the adhesive layer P9 and reach the lower part of the ceramic heater P1.

JP 2002-93677 A JP 2005-166354 A

  However, in the technique described above, since the through hole P7 for arranging the thermocouple P8 needs to be provided avoiding the cooling path P5 of the metal base P4, the temperature immediately above the through hole P7 (adsorption surface side) is a singular point (Ie, the point at which the temperature differs from the ambient temperature).

Therefore, there is a possibility that the temperature uniformity in the planar direction of the ceramic heater P1 (and thus the electrostatic chuck P6) may be deteriorated.
That is, there is a problem that the temperature distribution (in-plane temperature) in the planar direction of the electrostatic chuck P6 tends to be uneven.

  This invention is made in view of the said subject, The objective is to provide the heating member and electrostatic chuck which can equalize the temperature distribution in the planar direction of heating members, such as a ceramic heater, etc. .

  (1) The first aspect of the present invention includes a ceramic substrate on which a heat generating portion that generates heat when energized is disposed, and a bonding substrate different from the ceramic substrate, and the main surface of the ceramic substrate and the main surface of the bonding substrate are The heating member has a joined configuration, and the heat generating portion includes a plurality of heating elements disposed in a planar direction, and the heating member includes a plurality of heating areas set to include each of the plurality of heating elements. It is.

  In this heating member, on the ceramic substrate, the temperature detection elements for detecting the temperature are respectively disposed in the plurality of heating regions on the bonding substrate side from the heat generating portion in plan view, and are disposed in the plurality of heating regions The lead portions are connected to the plurality of temperature detection elements, and at least a part of the lead portions is disposed along the planar direction inside the ceramic substrate. Furthermore, the ceramic substrate is provided with a terminal portion connected to the other end side of the lead portion opposite to the temperature detection element, and the bonding substrate is electrically connected to the terminal portion and the electrical connection substrate in a thickness direction. Through-holes are provided for the placement of the connectors to be connected.

  Thus, in the first aspect, at least a part of each lead portion of each temperature detection element arranged in each heating region is arranged along the planar direction. The ceramic substrate is provided with a terminal portion connected to the other end side of each lead portion opposite to the temperature detection element, and the bonding substrate is provided with a connector electrically connected to the terminal portion. The penetration part of is provided.

  Therefore, unlike the prior art, it is not necessary to provide a through hole for disposing the temperature detection element immediately below (on the side of the bonding substrate) each heating element with respect to the bonding substrate. Therefore, since generation | occurrence | production of the singular point of the temperature by a through-hole can be suppressed, the temperature uniformity in the plane direction of a heating member can be improved.

(2) In the second aspect of the present invention, the plurality of terminal portions to which the plurality of lead portions extending from the plurality of temperature detection elements are connected are disposed at predetermined positions connected to the same connector.
In the second aspect, since the plurality of terminal portions are arranged to be connected to the same connector, the number of penetrations penetrating the bonding substrate can be reduced. Thus, temperature uniformity in the planar direction of the heating member can be further improved.

Here, the "predetermined position" is a position at which a plurality of terminal portions are arranged to be connectable to the same connector.
(3) In the third aspect of the present invention, a pair of lead portions are connected to the plurality of temperature detection elements, and one lead portion of the plurality of pair of lead portions connected to the plurality of temperature detection elements In each case, at least a portion extending along the planar direction is a common lead portion.

  In the third aspect, among the lead portions of the pair of lead portions connected to the plurality of temperature detection elements, the portion extending along the planar direction is a common lead portion, so the configuration of the lead portion Can be simplified.

  (4) In the fourth aspect of the present invention, a pair of lead portions are connected to the plurality of heating elements, and one lead portion of the plurality of pair of lead portions connected to the plurality of heating elements At least a portion extending along the planar direction is a common lead portion, and a common lead portion connected to a plurality of heating elements and a common lead portion of a plurality of temperature detection elements are the same common It is considered to be the lead part of

  In the fourth aspect, a portion of one of the lead portions of the plurality of paired lead portions connected to the plurality of heating elements is a portion extending along the planar direction as a common lead portion, and is connected to the plurality of heating elements The common lead portion and the common lead portion of the plurality of temperature detection elements are the same common lead portion. Therefore, the configuration of the lead portion can be further simplified.

(5) In the fifth aspect of the present invention, the bonded substrate is provided with a flow path of a coolant for cooling the heating member.
In the fifth aspect, the heating member can be suitably cooled by the refrigerant flowing through the flow path.

(6) In the sixth aspect of the present invention, the temperature detection element is disposed at a position overlapping the flow path of the refrigerant in plan view.
In the sixth aspect, since the temperature detection element is disposed at a position overlapping the flow path of the refrigerant, it can be suppressed that the temperature immediately above the temperature detection element becomes a singular point of temperature.

  Moreover, since it is not necessary to provide the flow path of the refrigerant so as to avoid the through hole as in the conventional case, the advantage that the flow path of the refrigerant can be provided at the most preferable position for cooling (for example, a position where cooling can be more evenly). There is.

(7) In the seventh aspect of the present invention, the surface of the ceramic substrate on the bonding substrate side is provided with a recess, and the temperature detection element is disposed in the recess.
In the seventh aspect, a recess is provided in the ceramic substrate, and the temperature detection element is disposed in the recess, so that the ceramic substrate and the bonding substrate can be suitably bonded. That is, there is an advantage that the temperature detection element does not easily interfere with bonding.

(8) In the eighth aspect of the present invention, the recess is filled with a filler that fills the periphery of the temperature detection element.
In the eighth aspect, since the filler is filled around the temperature detection element (that is, it is filled so that there is no gap), there is an advantage that the thermal conductivity is high and the recess is unlikely to become a singular point of temperature .

(9) The ninth aspect of the present invention is provided with a lid that closes the opening of the recess.
In the ninth aspect, since the recess is covered, it is difficult to form a gap between the ceramic substrate and the bonding substrate, and hence bonding can be performed suitably.

(10) A tenth aspect of the present invention is an electrostatic chuck comprising the heating member according to any one of the first to ninth aspects and a ceramic substrate provided with a suction electrode.
In the tenth aspect, there is an effect that temperature uniformity in the planar direction of the electrostatic chuck is high.

Hereinafter, each configuration of the present invention will be described.
-A ceramic substrate is a substrate (plate-like member) which has ceramic as a main component (50 mass% or more). Examples of the material of this ceramic include aluminum oxide (alumina), aluminum nitride, yttrium oxide (yttria) and the like.

The ceramic substrate used for the electrostatic chuck is a ceramic insulating plate having electrical insulation.
The main surface is a surface that forms an end in the thickness direction of the plate material (substrate).

  The heat generating portion (that is, the heat generating body) is a resistance heat generating body that generates heat when current is supplied, and examples of the material of the heat generating body include tungsten, tungsten carbide, molybdenum, molybdenum carbide, tantalum, platinum and the like.

The heating area is an area set to include each heating element in plan view.
The lead portion is a portion having conductivity, and examples of the material include tungsten and molybdenum.

  -A temperature detection element is an element which detects ambient temperature, and as this temperature detection element, a resistance temperature sensor which resistance value changes with temperature is mentioned. For example, a thermistor, a platinum temperature measuring resistor, etc. are mentioned.

The terminal portion is a conductive portion (provided on the ceramic substrate) to be connected to the conductive portion of the connector, and a pin or a pin hole or the like into which the pin is inserted can be adopted.
The connector is a conductive member having a conductive portion (for example, a pin hole) to be connected to a conductive portion (for example, a pin) of another member, that is, a member that performs an electrical connection.

The through portion is a through hole provided so as to penetrate the bonding substrate in the thickness direction.
-As a material of an adsorption electrode, tungsten, molybdenum etc. are mentioned.
· The bonding substrate is a plate material bonded to the ceramic substrate, and as its material, metals such as copper, aluminum, iron, titanium, alloys of these metals, composite materials of ceramic and metal (for example, Al-SiC), etc. Can be mentioned.

It is a perspective view which shows the electrostatic chuck of 1st Embodiment. It is sectional drawing which fractures | ruptures the electrostatic chuck of 1st Embodiment in the thickness direction, and shows the one part. (A) is a top view which shows arrangement | positioning of the heating area | region of a ceramic heater, (b) is a top view which shows arrangement | positioning of the heat generating body of a ceramic heater. It is an explanatory view which fractures an electrostatic chuck in the thickness direction, and expands and shows a temperature detection element arranged in a crevice. (A) is an explanatory view which fractures an electrostatic chuck in the thickness direction, and expands and shows a connector and composition of the circumference of it, and (b) is an explanatory view showing a tip side of a tip connector part. It is explanatory drawing which shows positional relationship, such as a connector in an electrostatic chuck, a heat generating body, a temperature detection element, etc. in planar view. It is a top view which shows the structure of a common internal wiring layer. It is sectional drawing which fractures | ruptures the electrostatic chuck of 2nd Embodiment in the thickness direction, and shows the one part. It is sectional drawing which fractures | ruptures the ceramic heater of 3rd Embodiment in the thickness direction, and shows the one part. It is explanatory drawing of a prior art.

[1. First embodiment]
Here, as a first embodiment, for example, an electrostatic chuck capable of attracting and holding a semiconductor wafer will be described 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 for adsorbing the semiconductor wafer 3 which is a workpiece on the upper side of FIG. 1, and includes a ceramic heater (heating member) 5 and a metal base The bonding substrate) 7 is laminated and bonded by the adhesive layer 9.

  The upper surface (upper surface: suction surface) of FIG. 1 of the ceramic heater 5 is a first main surface A, and the lower surface is a second main surface B. 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 them, the ceramic heater 5 has a disk shape, and is formed of a ceramic substrate 17 provided with an adsorption electrode 11, a heat generating portion 13, a temperature detection element 15 (see FIG. 2) and the like.
The metal base 7 is in the form of a disc having a diameter larger than that of the ceramic heater 5 and is coaxially joined to the ceramic heater 5. 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 (therefore, the semiconductor wafer 3). As a cooling fluid, for example, a cooling fluid such as a fluorinated liquid or pure water can be used.

  Further, lift pin holes 21 and the like into which lift pins (not shown) are inserted are provided in the electrostatic chuck 1 at a plurality of locations so as to penetrate the electrostatic chuck 1 in the thickness direction. The lift pin hole 21 is also used as a flow path (cooling gas hole) for a cooling gas 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 based on FIGS. 2 to 4.
<Ceramic heater>
As schematically shown in FIG. 2, the ceramic heater 5 (and thus the ceramic substrate 17) has the second main surface B side on the third main surface C side of the metal base 7 by the adhesive layer 9 made of, for example, indium. It is joined.

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

  Inside the ceramic substrate 17, from the upper side of FIG. 2, as will be described in detail later, the adsorption electrode 11, a plurality of heating elements 23 constituting the heating section 13, a plurality of temperature detection elements 15 and the like are arranged. .

  Among these, the adsorption electrode 11 is electrically connected to a known electrode terminal (not shown) to which a voltage is applied. The heating elements 23 and the temperature detection element 15 are electrically connected to the power supply terminal 27 and the connector 29 through the internal wiring portion 25 as described later.

<Metal base>
The metal base 7 is made of metal made of aluminum or an aluminum alloy. In the metal base 7, in addition to the cooling path 19 and the lift pin hole 21, a through portion 31 which is a through hole in which the electrode terminal, the power supply terminal 27, the connector 29 and the like are arranged is formed.

  Note that, on the fourth main surface D side of the electrostatic chuck 1, there is an internal hole 30 that reaches the inside of the ceramic heater 5 from the fourth main surface D in order to accommodate the power supply terminal 27, the connector 29 and the like. A plurality of through-holes 31 of the metal base 7 constitute a part of the internal hole 30.

In addition, an insulating cylinder 33 having electrical insulation is disposed in the inner hole 30 for housing the electrode terminal and the power supply terminal 27 so as to surround the outer periphery of each terminal 27.
<Electrode for adsorption>
The adsorption electrode 11 is formed 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 suction electrode 11 to generate an electrostatic attractive force (adhesion force) to adsorb the semiconductor wafer 3. It is used to adsorb and fix the semiconductor wafer 3. In addition to the above, various known configurations (such as unipolar or bipolar electrodes) can be adopted as the adsorption electrode 11. The adsorption electrode 11 is made of, for example, a conductive material such as tungsten.

<Heating element>
The heating element 23 is a resistance heating element made of a metal material (such as tungsten) that generates heat when a voltage is applied and a current flows.

Here, based on FIG. 3, the arrangement in the plane direction of the heating element 23 will be described.
As shown in FIG. 3A, the ceramic substrate 17 has a plurality of heating zones 35 concentrically in a plan view so that each region in the planar direction of the ceramic substrate 17 can be heated (thus, temperature control). It is provided. In each heating zone 35, one or more heating regions 37 are set.

  Specifically, the heating zone 35 provided on the ceramic substrate 17 has a circular first heating zone 35a including the axial center and an annular second heating surrounding the outer circumferential side of the first heating zone 35a. Zone 35b, an annular third heating zone 35c surrounding the outer periphery of the second heating zone 35b in a band, and an annular fourth heating zone 35d surrounding the outer periphery of the third heating zone 35c in a band And they are arranged concentrically.

  Further, the second heating zone 35b is divided into three heating areas 37 so as to have the same central angle (equal pitch), and the third heating zone 35c is equally divided into three heating areas 37 at an equal pitch. The fourth heating zone 35d (i.e., the outermost heating zone) is divided into eight heating areas 37 at equal pitches. Therefore, the shape of each heating area 37 is a circular or curved arc-shaped area of a predetermined width.

  And as shown in FIG.3 (b), the heating element 23 is each arrange | positioned in the heating area | region 37 of the 1st heating zone 35a which is the single heating area | region 37, and the 2nd-4th heating zones 35b-35d. It is done.

In addition, the broken line of FIG. 3 has shown the boundary of each heating area | region 37, and each heat generating body 23 is shown with the continuous line in FIG.3 (b).
Each heating element 23 has a long heating pattern, and is formed, for example, in a U-shape in accordance with the shape of each heating area 37. Specifically, each heating element 23 has a shape curved along the curvature of the inner circumference and the outer circumference of each heating area 37, and is bent in a U-shape at one end in the circumferential direction. The heating element 23 in the first heating zone 35a has a long heat generation pattern (a part of which is cut away) in a circular shape in accordance with the circular shape.

<Temperature detection element>
The temperature detection element 15 is, for example, a thermistor whose resistance value changes with temperature, and is disposed at a position overlapping the heating region 37 and the cooling path 19 in plan view as described later.

  As shown in FIG. 4, the temperature detection element 15 is composed of, for example, a thermistor sintered body 39 and a pair of electrode wires 41 (41a, 41b) made of platinum extending from the thermistor sintered body 39.

The temperature detection element 15 is accommodated in a recess 43 provided on the second main surface B which is a bonding surface of the ceramic substrate 17.
A pair of electrode pads 47 are formed on the bottom surface 43a (upper surface in the recess 43 of FIG. 4) of the recess 43, and the electrode wire 41 is joined to the electrode pad 47 by brazing, for example.

  In addition, a filler 49 is filled in the recess 43 so that there is no gap. As the filler 49, for example, a material (for example, an epoxy resin or a silicone resin) having a thermal conductivity higher than that of air is used.

Furthermore, a lid 53 made of, for example, a ceramic plate that closes the opening 51 is disposed at the opening (opening at the second main surface B) 51 of the recess 43. The lid 53 is arranged such that its surface (lower surface) is the same surface as the second main surface B. As the material of the lid 53, the same material as the ceramic substrate 17 can be used.
[1-2. Wiring structure of heating element and temperature detection element]
Next, the wiring structure of the heating element 23 and the temperature detection element 15, which is a main part of the first embodiment, will be described based on FIG.

As shown in FIG. 2, an internal wiring portion 25 is provided inside the ceramic substrate 17 as a wiring structure for energizing the heating element 23 and the temperature detection element 15.
Specifically, as the internal wiring portion 25, a pair of lead portions (heating element lead portions) 55 (55 a, 55 b) are connected to the heating element 23, and similarly, the temperature detecting element 15 also has a pair of leads The parts (element lead parts) 57 (57a, 57b) are connected.

  These lead portions 55, 57 include vias 59 extending in the thickness direction (vertical direction in FIG. 2) of the ceramic substrate 17 and an internal wiring layer 61 extending in the planar direction (vertical direction with the thickness direction).

  Here, one internal wiring layer 61a disposed between the heating element 23 and the temperature detection element 15 and extending in the planar direction constitutes a part of one heating element lead portion 55a, and one element It constitutes a part of the lead portion 57a. That is, the internal wiring layer 61a having a circular shape (see FIG. 7) in plan view is used as a common wiring (that is, a common lead portion).

  Then, one heating element lead portion 55a of each heating element 23 is electrically connected to the common feeding terminal 27a via the via 59 and the common internal wiring layer 61a of its own and the electrode pad 63 of the inner hole 30. Connected. That is, one heating element lead 55 a of all the heating elements 23 is electrically connected to a single common feeding terminal 27 a among the plurality of feeding terminals 27.

  The electrode pad 63 is provided on the bottom surface 30a (upper surface in FIG. 2) of the internal hole 30, and the upper portion 28 of the power supply terminal 27 is joined to the electrode pad 63 by brazing, for example.

  On the other hand, the other heating element lead portion 55b of each heating element 23 is separately connected to a separate feeding terminal (ie, each feeding terminal provided on each heating element 23), although not shown. It is done.

  Similarly, one element lead portion 57a of each temperature detection element 15 is electrically connected to the common power supply terminal 27a through the electrode pad 63, with its own via 59 and the common internal wiring layer 61a. Connected. That is, one element lead portion 57a of all the temperature detection elements 15 is electrically connected to a single common power supply terminal 27a.

  On the other hand, the other element lead portion 57b of each temperature detection element 15 is composed of a via 59 and an internal wiring layer 61b (for the temperature detection element 15) extending in the planar direction, among which each internal wiring layer The terminals 61 b are connected to terminal portions 65 (see FIG. 5), which will be described later, via the vias 59 immediately above the internal holes 30 (for the connector 29).

  Then, as described later, the other element lead portion 57 b of each temperature detection element 15 is separately electrically connected to each connection portion 67 (see FIG. 5) of the connector 29 through each terminal portion 65. It is done.

The respective terminal portions 65 and the respective connection portions 67 are provided in one-to-one correspondence with the respective temperature detection elements 15.
<Connector>
Here, the connector 29 and the configuration around it will be described in detail based on FIG.

  As shown in FIG. 5, the bottom surface 30b (upper surface in FIG. 5) of the internal hole 30 in which the connector 29 is disposed is connected to the plurality of other element lead portions 57b and vias 59 that constitute the internal wiring portion 25. A plurality of electrode pads 71 are provided.

  The electrode pad 71 is provided corresponding to the other element lead portion 57 b of each temperature detection element 15, and a pin 73 constituting each terminal portion 65 is provided upright on each electrode pad 71. It is attached. That is, on the bottom surface 30b of the internal hole 30 for the connector, the pins 73 for the number of the other element lead portions 57b are erected.

  The connector 29 has an electrically insulating resin tip connector portion 75 disposed at the back of the internal hole 30 (upper part in FIG. 5A) and the lower part of the opening part of the internal hole 30 (FIG. 5A) And a cable portion 79 for connecting the front end connector portion 75 and the rear end connector portion 77.

  The distal end connector portion 75 is a substantially rectangular parallelepiped, and a connection portion 67 having a large number of pin holes 83 into which the pins 73 can be inserted is formed on the distal end surface 81 (see FIG. 5B). That is, the connecting portion 67 is formed of a conductive material which constitutes the periphery of each pin hole 83 and extends to the cable portion 79 side. The number of pin holes 83 is set to be equal to or more than the number of temperature detection elements 15 (for example, the same number).

On the other hand, the rear end connector portion 77 also has a configuration similar to that of the front end connector portion 75, that is, a configuration having a large number of pin holes 85 (therefore connecting portions 87).
The connection portions 67 of the front end connector portion 75 and the connection portions 87 of the rear end connector portion 77 are electrically connected by the conductive wires 89 of the cable portion 79, respectively.

  Therefore, by pushing the tip connector portion 75 of the connector 29 into the internal hole 30, it is possible to connect each terminal portion 65 (i.e. pin 73) and each connection portion 67 (i.e. pin hole 83) to obtain conduction. .

<Positional relationship between connector and temperature detection element>
Next, the positional relationship between the connector 29 and the temperature detection element 15 will be described in detail based on FIG.

  In FIG. 6, the temperature detection element 15 is shown by a rectangular frame substantially at the center of each heating area 37 in plan view, and among these, black circles in the frame are connected to a common internal wiring layer 61a. And the white circle indicates the other electrode line 41b.

As shown in FIG. 6, the connector 29 is disposed at the central portion of the electrostatic chuck 1 in plan view.
Further, as described above, each connection portion 67 of the connector 29 (specifically, the tip connector portion 75) is connected to the other electrode wire 41b of each temperature detection element 15.

  Therefore, the central connector 29 and the other electrode wire 41b (more specifically, the electrode pad 47: see FIG. 4) of each temperature sensing element 15 disposed in each heating area 37 around it extend radially from the center. Are electrically connected by the other element lead portion 57b.

  Apart from this, one of the electrode lines 41a (see FIG. 4) is the upper side of FIG. 4 by the via 59 (that is, the via 59 extending upward in FIG. 4) extending perpendicularly from the electrode pad 47 to the sheet of FIG. It is electrically connected to the circular common internal wiring layer 61a disposed on the (first principal surface A side).

That is, one electrode line 41a and its electrode pad 47 and via 59 are electrically connected to the internal wiring layer 61 shown in FIG. 7 at a black square position.
Further, in FIG. 6, among the both ends 23a and 23b of the heating element 23, the end 23a connected to the common internal wiring layer 61a (thus, the common feeding terminal 27a) is shown by a black circle, The end 23b connected to 27 is indicated by a white circle.

  Therefore, as shown in FIG. 7, the end 23a connected to the common internal wiring layer 61a has a position shown by a black circle in FIG. 7 (that is, directly below the end 23a) via the via 59 extending in the thickness direction: It is connected to the common internal wiring layer 61a on the two main surfaces B side).

On the other hand, the end 23b connected to each feed terminal 27 is connected to each feed terminal 27 via a through hole 91 shown by a white circle in FIG.
Here, the through hole 91 is described at the same position as the end 23 b for easy understanding, but in practice, the other (extending in the planar direction) interior so as to avoid the cooling path 19 etc. Through holes 91 are provided at appropriate positions via the wiring layer 61.

In FIG. 7, the other through holes for the lift pin holes 21 and the like are omitted.
<Others>
Although not shown, a power supply circuit is connected to the suction electrode 11, the heating element 23, and the temperature detection element 15 of the electrostatic chuck 1 in order to operate them. It is controlled by the controller.

  That is, the operation of the adsorption electrode 11 can be controlled (control of the applied voltage and the like) by the electronic control unit. In addition, the operation of all the heating elements 23 can be controlled independently. Furthermore, by energizing the temperature detection element 15, the temperature in each heating area 37 can be detected from the change of the resistance value.

When the electrostatic chuck 1 is cooled, the ceramic heater 5 (and thus the semiconductor wafer 3) can be cooled by flowing a cooling fluid in the cooling passage 19.
[1-2. Production method]
Next, a method of manufacturing the electrostatic chuck 1 of the first embodiment will be briefly described.

(1) As a raw material of the ceramic substrate 17, powders of 92 wt% of Al ₂ O ₃ as a main component, 1 wt% of MgO, 1 wt% of CaO, 6 wt% of SiO ₂ are mixed to obtain a ball mill After wet grinding for 50 to 80 hours, it is dewatered and dried.

(2) Next, a solvent etc. is added to this powder, and it mixes with a ball mill to make a slurry.
(3) Next, the slurry is defoamed under reduced pressure, poured into a flat plate shape, and gradually cooled to evaporate the solvent to form alumina green sheets (corresponding to the respective ceramic layers).

Then, with respect to each of the alumina green sheets, a space to be the lift pin hole 21, the internal hole 30, the recess 43 or the like, and a through hole to be the via 59 are opened at necessary places.
(4) Further, tungsten powder is mixed into the raw material powder for the alumina green sheet to form slurry and metallized ink.

  (5) And, in order to form the suction electrode 11, the heat generating body 23, the internal wiring layer 61, etc., the metallized ink is used to correspond to the formation position of the suction electrode 11, the heat generating body 23, the internal wiring layer 61 Each pattern is printed on the alumina green sheet by the usual screen printing method. In order to form the vias 59, metallizing ink is filled in the through holes.

(6) Next, the respective alumina green sheets are aligned so as to form the necessary space such as the lift pin holes 21 and the like, and thermocompression bonding is performed to form a laminated sheet.
(7) Next, each laminated sheet that has been subjected to thermocompression bonding is cut into a predetermined shape (that is, a disk shape).

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

(10) Next, electrode pads 47, 63, 71 are formed in the necessary places of the ceramic substrate 17.
(11) Next, for example, the pin 74 is soldered to the electrode pad 71. Further, the upper portion 28 of the power supply terminal 27 is brazed to the electrode pad 63.

  (12) Separately, manufacture the metal base 7. Specifically, the metal base 7 provided with the internal holes 30 and the like is formed by performing a cutting process or the like on the metal plate. An insulating cylinder 33 is disposed in the inner hole 30.

(13) Next, the metal base 7 and the ceramic substrate 17 are joined and integrated.
(14) Next, the connector 29 and the power supply terminal 27 are arranged corresponding to each internal hole 30, and the electrostatic chuck 1 is completed.
[1-3. effect]
Next, the effect of the first embodiment will be described.

  In the first embodiment, at least a portion (that is, the individual internal wiring layer 61b) of the other element lead portion 57b of each temperature detection element 15 disposed corresponding to each heating area 37 extends in the planar direction. The ceramic substrate 17 is provided with a terminal portion 65 connected to the other element lead portion 57b. Further, the metal base 7 is provided with a through portion 31 for disposing a connector 29 electrically connected to the terminal portion 65 so as to penetrate the metal base 7 in the thickness direction.

  Therefore, it is not necessary to provide a through hole for disposing the temperature detection element 15 immediately below each metal heater 7 (on the side of the metal base 7) as in the prior art. Therefore, since the generation of a singular point of temperature due to the through hole can be suppressed, temperature uniformity in the planar direction of the ceramic heater 5 (that is, the electrostatic chuck 1) can be enhanced.

  In the first embodiment, each terminal portion 65 to which the other element lead portion 57b extending from the plurality of temperature detection elements 15 is connected is a predetermined position connected to the same connector 29 (ie, the internal hole 30 for the connector Bottom surface 30b).

Therefore, the number of the through portions 31 penetrating the metal base 7 can be reduced, so that the temperature uniformity in the planar direction of the ceramic heater 5 can be further enhanced.
In the first embodiment, a part of one of the element lead portions 57a of the plurality of temperature detection elements 15 is a common internal wiring layer 61a extending in the planar direction. Further, a part of one heating element lead 55a of the heating element 23 is also the common internal wiring layer 61a.

Therefore, there is an advantage that the wiring structure in the ceramic heater 5 can be simplified.
In the first embodiment, since the metal base 7 includes the cooling path 19 for cooling the ceramic heater 5, the ceramic heater 5 can be suitably cooled.

In the first embodiment, since the temperature detection element 15 is disposed at a position overlapping the cooling path 19 in plan view, it can be suppressed that the temperature immediately above the temperature detection element 15 becomes a singular point of temperature.
Further, since it is not necessary to provide the cooling passage 19 so as to avoid the through hole as in the prior art, the cooling passage 19 can be provided at the most preferable position for cooling.

In the first embodiment, since the temperature detection element 15 is disposed in the recess 43 of the ceramic substrate 17, the ceramic substrate 17 and the metal base 7 can be suitably joined.
In the first embodiment, since the filler 49 is filled around the temperature detection element 15 in the recess 43, there is an advantage that the thermal conductivity is high and the recess 43 is unlikely to become a singular point of temperature.

In the first embodiment, since the lid 53 is provided in the recess 43, it is difficult to form a gap between the ceramic substrate 17 and the metal base 7, and therefore, it is possible to join suitably.
[2. Second embodiment]
Next, a second embodiment will be described, but the description of the same content as that of the first embodiment will be omitted or simplified. The same components as those in the first embodiment are denoted by the same reference numerals.

  As shown in FIG. 8, in the electrostatic chuck 101 of the second embodiment, as in the first embodiment, the ceramic heater 103 and the metal base 7 are joined, and the ceramic substrate 105 of the ceramic heater 103 is used. A plurality of heating elements 23 and a plurality of temperature detection elements 15 are disposed in the interior of the device.

  In particular, in the second embodiment, one heating element lead portion 107a of each heating element 23 is connected to a single common feeding terminal 27 via the common internal wiring layer 109 for heating element. There is. The other heating element lead portion 107b of each heating element 23 is connected to an individual feed terminal (not shown) as in the first embodiment.

  Further, one element lead portion 111 a of each temperature detection element 15 is connected to a single common power supply terminal (not shown) via the common internal wiring layer 113 for the temperature detection element. The other element lead portion 111b of each temperature detection element 15 is connected to a single connector 29 as in the first embodiment.

The second embodiment exhibits the same effect as the first embodiment. In addition, since the circuit of the heating element 23 and the circuit of the temperature detection element 15 are separated (that is, since a common internal wiring layer is not used), there is an advantage that more accurate temperature detection and temperature control can be performed.
[3. Third embodiment]
Next, a third embodiment will be described, but the description of the same content as that of the second embodiment will be omitted or simplified. The same components as those in the second embodiment are denoted by the same reference numerals.

  As shown in FIG. 9, the ceramic heater 121, which is a heating member of the third embodiment, is a ceramic heater substantially similar to that of the second embodiment, but has a metal base and an adsorption electrode as in the second embodiment. I do not prepare.

  As in the second embodiment, the ceramic substrate 123 of the ceramic heater 121 is provided with a plurality of heating elements 23 and a plurality of temperature detection elements 15, and the respective internal wiring layers 109 and 113 connected thereto and terminals for feeding. 27 and the connector 29 etc.

Here, the other ceramic substrate 125 is bonded to the second main surface B side of the ceramic substrate 123, but the other ceramic substrate 125 may be omitted.
In the third embodiment, as in the first embodiment, it is possible to achieve soaking in the planar direction of the ceramic heater 121.

The present invention is not limited to the above embodiment and experimental examples, and it goes without saying that the present invention can be practiced in various forms without departing from the present invention.
(1) For example, other than the configuration in which the other element lead portion of the plurality of temperature detection elements is concentrated on one connector, it may be divided into a plurality of connectors.

Alternatively, one connector (and thus one terminal portion) may be used for each element lead portion of each temperature detection element.
(2) The arrangement of connectors for concentrating a plurality of element lead portions is not limited to the center of the ceramic heater, and may be appropriately arranged such as a peripheral portion.

  (3) Although a common lead portion (for example, an internal wiring layer) partially extending in the planar direction is used as each one element lead portion of each temperature detection element, each one and the other element lead of each temperature detection element Some of the parts may extend in the planar direction.

(4) It is not necessary to arrange the temperature detection element at a position overlapping the flow path of the refrigerant in plan view.
(5) The recess may not be filled with a filler that fills the periphery of the temperature detection element. In addition, when joining a metal base with an adhesive agent, you may make it an adhesive agent have a function of a filler.

(6) It is not necessary to provide a lid in the recessed part which accommodates a temperature detection element.
(7) Contrary to each embodiment, a pin hole may be provided on the bottom of the inner hole for housing the connector, and a pin may be provided on the connector side.

(8) In each embodiment, the electrode wire of the temperature detection element is brazed to the electrode pad, but a configuration like a pin hole may be provided on the electrode pad side, and the electrode wire may be inserted into the pin hole.
(9) As the temperature detection element, a platinum temperature measuring resistor or the like can be used other than the thermistor.

  (10) The configurations of the embodiments can be combined as appropriate.

1, 101 ... electrostatic chuck 5, 103, 121 ... ceramic heater 7 ... metal base (bonded substrate)
11 ... adsorption electrode 13 ... heat generation portion 15 ... temperature detection element 17, 105, 123 ... ceramic substrate 19 ... cooling path (flow path of refrigerant)
23: heating element 29: connector 31: penetrating portion 37: heating area 43: concave portion 49: filler 51: opening portion 53: lid 55, 55a, 55b, 107a, 107b: heating element lead portion 57, 57a, 57b, 111a 111 b: Element lead portion 65: Terminal portion

Claims (11)

A ceramic substrate on which a heat generating portion that generates heat when energized is disposed, and a bonding substrate different from the ceramic substrate, and the main surface of the ceramic substrate and the main surface of the bonding substrate are bonded together ,
The heating unit includes a plurality of heating elements arranged in a planar direction, and the heating member includes a plurality of heating areas set to include each of the plurality of heating elements.
On the ceramic substrate, a temperature detection element for detecting a temperature is disposed in each of the plurality of heating regions in plan view on the side of the bonding substrate with respect to the heat generating portion,
A lead portion is connected to each of the plurality of temperature detection elements disposed in the plurality of heating regions, and at least a part of the lead portion is disposed along the planar direction inside the ceramic substrate,
Furthermore, the ceramic substrate is provided with a terminal portion connected to the other end side of the lead portion opposite to the temperature detection element,
A heating member characterized in that the bonding substrate is provided with a through portion for arranging a connector electrically connected to the terminal portion so as to penetrate the bonding substrate in the thickness direction.   The plurality of terminal portions to which the plurality of lead portions extending from the plurality of temperature detection elements are connected are disposed at predetermined positions connected to the same connector. Heating member.   A pair of the lead portions is connected to the plurality of temperature detection elements, and one of the lead portions of the plurality of pair of lead portions connected to the plurality of temperature detection elements is at least in a planar direction The heating member according to claim 1 or 2, wherein a portion extending along is a common lead portion. A pair of lead portions are connected to the plurality of heating elements, and one of the lead portions of the pair of lead portions connected to the plurality of heating elements extends at least along the plane direction The part is a common lead part,
The common lead portion connected to the plurality of heating elements and the common lead portion of the plurality of temperature detection elements are the same common lead portion. Heating member.   The heating member according to any one of claims 1 to 4, wherein the bonding substrate includes a flow path of a refrigerant that cools the heating member.   The heating member according to claim 5, wherein the temperature detection element is disposed at a position overlapping the flow path of the refrigerant in the plan view.   The heating member according to any one of claims 1 to 6, wherein a recess is provided on a surface of the ceramic substrate on the bonding substrate side, and the temperature detection element is disposed in the recess.   The heating member according to claim 7, wherein the recess is filled with a filler filling the periphery of the temperature detection element.   The heating member according to claim 7 or 8, further comprising a lid closing the opening of the recess. The heating member according to any one of claims 1 to 9, wherein the lead portion is embedded in the ceramic substrate. An electrostatic chuck comprising the heating member according to any one of claims 1 to 10 , wherein the ceramic substrate is provided with a suction electrode.

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