JP2019079774A - Heater and heater system - Google Patents

Abstract

To provide a heater that can optimize the conduction of a through conductor to a resistive heating element.SOLUTION: A heater includes a substrate, a resistance heating element 2, a plurality of connection conductors 3a, and a terminal 5. The substrate includes an upper surface and has insulation property. The resistance heating element 2 extends along the upper surface in the substrate. Each of the plurality of connection conductors 3a includes a portion extending from the resistance heating element 2 to the opposite side to the side facing the upper surface. The terminal 5 is exposed to the side opposite to the side facing the upper surface. The plurality of connection conductors 3a electrically connected in parallel to one terminal 5 are arranged along a path of the resistance heating element 2 in the extending direction of the resistance heating element 2.SELECTED DRAWING: Figure 5

Description

  The present disclosure relates to a heater and a heater system.

  In the technical field such as a semiconductor manufacturing apparatus, a ceramic heater (hereinafter sometimes simply referred to as a "heater") is widely used to heat a semiconductor substrate (hereinafter also referred to as "wafer"). The heater is embedded in, for example, a disk-shaped ceramic base on which the wafer is placed on the upper surface, and the ceramic base, and extends along the upper surface of the ceramic base in a suitable pattern (for example, spiral) And a resistive heating element.

  In the heater of patent document 1, the wiring for electrically feeding to a resistance heating element is embed | buried under the ceramic base material. The wiring extends along the upper surface of the ceramic base on the lower surface side of the resistance heating element. The resistance heating element and the wiring are connected by a plurality of through conductors penetrating a part of the ceramic base in the thickness direction. More specifically, the resistance heating element is widened at an end, and a plurality of through conductors are connected to the end.

JP, 2015-191837, A

  It is desirable to provide a heater and heater system that can optimize the conduction of the through conductor to the resistive heating element.

  A heater according to an aspect of the present disclosure includes: an insulating base having a predetermined surface; a resistive heating element extending along the predetermined surface on or in the predetermined surface; A plurality of connection conductors each including a portion extending from the heating element to the opposite side to the side facing the predetermined surface, and the other side exposed to the side facing the predetermined surface of the base, The plurality of connection conductors are electrically connected in parallel with one another, and the plurality of connection conductors are arranged along a path of the resistance heating element in a direction in which the resistance heating element extends It is done.

  In one example, the heater is spaced apart from the resistance heating element on the opposite side to the side facing the predetermined surface, extends from the plurality of connection conductors along the predetermined surface, and is electrically connected to the terminal It further has a wiring pattern connected in a manner as described above.

  In one example, the sum of the areas of the cross sections orthogonal to the extending direction of the plurality of connection conductors is larger than the area of the cross section orthogonal to the extending direction of the resistance heating element.

  In one example, the area of the cross section orthogonal to the extending direction of the wiring pattern is larger than the sum of the areas of the cross sections orthogonal to the extending direction of the plurality of connection conductors.

  In one example, the diameter in the width direction of the resistance heating element of at least one of the plurality of connection conductors is 0.9 times or more and 1.1 times or less the width of the resistance heating element.

  In one example, the base is made of a ceramic, and at least one of the plurality of connection conductors is made of a pure metal or an alloy containing only a metal element.

  In one example, the metal element of the pure metal or the metal element of the main component of the alloy is tungsten or molybdenum.

  In one example, at least any one of the plurality of connection conductors penetrates the resistance heating element.

  In one example, at least any one of the plurality of connection conductors penetrates the wiring pattern.

  In one example, the wiring pattern includes a plurality of wirings electrically connected to the terminals in parallel to one another and separately connected to the plurality of connection conductors.

  A heater system according to an aspect of the present disclosure includes the above-described heater and a drive device that supplies power to the terminal.

  According to the above configuration, the conduction of the through conductor to the resistance heating element can be optimized.

It is a schematic diagram showing composition of a heater system concerning a 1st embodiment. It is a disassembled perspective view of the heater of the heater system of FIG. It is a top view which shows the inside of the heater of FIG. It is sectional drawing in the IV-IV line of FIG. It is an enlarged perspective view which shows a part of conductor inside the heater of FIG. 6 (a) is a schematic view showing an outline of the configuration of a control system in the heater system of FIG. 1, and FIG. 6 (b) schematically shows an example of temperature control by the control system of FIG. 6 (a). FIG. Fig.7 (a) is an enlarged perspective view of a part of heater which concerns on 2nd Embodiment, FIG.7 (b) is sectional drawing in the VIIb-VIIb line of FIG. 7 (a). FIGS. 8A and 8B are cross-sectional views for explaining a method of manufacturing the heater of FIG. 7A. FIG. 9 (a) is a cross-sectional view showing a modification of the manufacturing method of FIG. 8 (a), and FIG. 9 (b) is a cross-sectional view showing another modification of the manufacturing method of FIG. 8 (a). Fig.10 (a)-FIG.10 (c) are schematic diagrams which show a various modification. FIGS. 11A and 11B are cross-sectional views showing various modifications. 12 (a) is a view showing an application example to which the heater system of the present disclosure is applied, and FIG. 12 (b) is a view for explaining the details of the application example in FIG. 12 (a).

  Hereinafter, a ceramic heater and a heater system according to an embodiment of the present disclosure will be described with reference to the drawings. However, the respective drawings referred to below are schematic for the convenience of description. Accordingly, details may be omitted, and dimensional proportions may not always coincide with reality. The ceramic heater and the heater system may further include known components not shown in the drawings.

  In the second and subsequent embodiments, the same components as those of the above-described embodiment are denoted by the same reference numerals as those of the above-described embodiment, and the description will be made. May be omitted. Even if the code corresponding to (similar to) the configuration of the embodiment described above is given a code different from the reference numeral attached to the configuration of the embodiment described above, a matter that is not particularly noted May be similar to the configuration of the embodiment described above.

First Embodiment
(Heater system)
FIG. 1 is a schematic view showing the configuration of a heater system 100 according to the embodiment.

  The heater system 100 includes a heater (ceramic heater) 10 and a drive device 50 for driving the heater 10. Hereinafter, these will be described in order.

  Note that the heater 10 does not necessarily have to be used with the upper side of the sheet of FIG. 1 as the actual upper side. In the following, for convenience, terms such as the upper surface and the lower surface may be used, assuming that the upper side of the paper surface of FIG. 1 is the actual upper side.

(heater)
The heater 10 has, for example, a substantially plate-like (in the illustrated example, a disk-like) heater main body 10a and a pipe 10b extending downward from the heater main body 10a.

  The heater main body 10a is a portion on which the wafer as an example of the heating target is placed on the upper surface 10c and which directly contributes to the heating of the wafer. The pipe 10b is, for example, a portion that contributes to the support of the heater main body 10a and / or the protection of a cable (not shown) connected to the heater main body 10a. In addition, a heater may be defined only by the heater main body 10a except the pipe 10b.

  The upper surface 10c and the lower surface (reference numeral omitted) of the heater main body 10a are, for example, substantially flat. The planar shape and various dimensions of the heater main body 10a may be appropriately set in consideration of the shape, dimensions, and the like of the object to be heated. For example, the planar shape is a circle (example shown) or a rectangle. When an example of a dimension is shown, a diameter is 20 cm or more and 35 cm or less, and a thickness is 5 mm or more and 30 mm or less.

  The pipe 10b is a hollow member which is open at the top and bottom (both sides in the axial direction) (see also FIG. 2). The shapes of the cross section (the cross section orthogonal to the axial direction) and the longitudinal cross section (the cross section parallel to the axial direction) and various dimensions may be set as appropriate. In the illustrated example, the pipe 10b has a cylindrical shape whose diameter is constant with respect to the axial position. Moreover, the cross section of the pipe 10b is smaller than, for example, the lower surface of the heater main body 10a. The pipe 10b is located at the center of the lower surface of the heater body 10a.

  The pipe 10b may be made of an insulating material such as ceramic, or may be made of a metal (conductive material). The pipe 10b may be formed of the same material as the heater main body 10a (strictly speaking, the base 1 described later), and may be fixed to the heater main body 10a by being integrally formed with the heater main body 10a. It may be made separately from the main body 10a, and may be fixed to the heater main body 10a by screws, other fasteners, or an adhesive.

  In the planar see-through, a region defined by the inner edge of the pipe 10b in the heater body 10a is a terminal arrangement region 10d (see FIG. 3) in which a plurality of terminals 5 (see FIG. 2) described later are arranged. The plurality of terminals 5 are exposed to the outside of the heater body 10a from the lower surface of the heater body 10a.

  A plurality of cables (not shown) are inserted into the pipe 10b. One end of the plurality of cables is connected to the plurality of terminals 5, and the other end is connected to the drive device 50. Thereby, the heater main body 10a and the drive device 50 are electrically connected. The plurality of cables may be integrated into one cable, or may not be integrated.

(Internal structure of heater body)
FIG. 2 is an exploded perspective view of the heater 10. In addition, the heater 10 or the heater main body 10a after completion is integrally formed, for example, non-degradable. That is, they do not have to be disassemblable as in the exploded perspective view of FIG.

  The heater main body 10a has an insulating base 1 (see FIG. 1; in FIG. 2, it comprises 1a, 1b and 1c in FIG. 2), a resistance heating element 2 embedded in the base 1, and electric power for the resistance heating element 2. And various conductors for supplying the The various conductors are, for example, the connection portion 3 (shown more schematically in FIG. 2 to FIG. 4 than in FIG. 5), the wiring 4 and the terminal 5. The flow of current through the resistance heating element 2 generates heat in accordance with Joule's law, which in turn heats the wafer placed on the upper surface 10 c of the substrate 1.

(Substrate)
The outer shape of the base 1 constitutes the outer shape of the heater main body 10a. Therefore, the above description regarding the shape and dimensions of the heater main body 10a may be taken as the description of the outer shape and dimensions of the base 1 as it is.

The material of the base 1 is, for example, a ceramic. The ceramic is, for example, a sintered body containing aluminum nitride (AlN), aluminum oxide (Al ₂ O ₃ ), silicon carbide (SiC), silicon nitride (Si ₃ N ₄ ) or the like as a main component. In addition, the aluminum nitride-type ceramics which have aluminum nitride as a main component are excellent in corrosion resistance, for example. Therefore, when the substrate 1 is made of an aluminum nitride ceramic, it is advantageous for use under, for example, a highly corrosive gas atmosphere.

  The main component is, for example, a component that occupies 50% or more or 80% or more of the mass of the material. The same applies to the main components of the alloys described later.

  In FIG. 2, the substrate 1 is composed of a first ceramic layer 1a to a third ceramic layer 1c. The base 1 may be manufactured by laminating materials (for example, ceramic green sheets) to be the first ceramic layer 1a to the third ceramic layer 1c, or manufactured by a method different from such a method, and completed It may only be able to be grasped to be conceptually formed of the first ceramic layer 1a to the third ceramic layer 1c conceptually due to the presence of the resistance heating element 2 and the like later.

  The first ceramic layer 1a is a layer constituting the upper surface 10c of the heater main body 10a. The third ceramic layer 1c is a layer that constitutes the lower surface of the heater body 10a. The second ceramic layer 1 b is a layer located between the first ceramic layer 1 a and the third ceramic layer 1 c. Each of the first ceramic layer 1a to the third ceramic layer 1c is, for example, a layer (plate) having a substantially constant thickness, and the plane shape thereof is the plane shape of the entire heater main body 10a (base 1) described above. Is the same as The thickness of each layer may be appropriately set according to the role of each layer.

(Resistant heating element)
The resistance heating element 2 is constituted of a conductor pattern located between the first ceramic layer 1a and the second ceramic layer 1b. The conductor pattern extends along the upper surface (along the upper surface 10c of the base 1 in another aspect) on the upper surface of the second ceramic layer 1b (in another aspect, the lower surface of the first ceramic layer 1a). The resistance heating element 2 is generally linear.

  FIG. 3 is a plan view showing the upper surface of the second ceramic layer 1b.

  For example, only one resistance heating element 2 is provided in the heater main body 10a, and the resistance heating element 2 does not cross with itself from one end (first main feeding portion Pa) to the other end (second main feeding portion Pb). It extends.

  Both ends of the resistance heating element 2 are a first main feeding part Pa and a second main feeding part Pb for supplying power to the resistance heating element 2 (hereinafter referred to simply as “main feeding part P”, and the two should not be distinguished. There is However, the main feeding portion P may be offset from both ends of the resistance heating element 2. Further, regardless of the presence or absence of such a deviation, the term may be defined to use the word of the resistive heating element 2 for the portion between the pair of main feeding parts P. In the following description, for the sake of convenience, both ends of the resistance heating element 2 and the pair of main feeding parts P are synonymous.

  The resistance heating element 2 does not have to have a special configuration (for example, in the form of a pad) in the main feeding portion P, and may have the same configuration as most of the resistance heating element 2 . In FIG. 3, for convenience of clarifying the position of the main feeding portion P, a through conductor (reference numeral omitted) penetrating the second ceramic layer 1 b is illustrated at the position of the main feeding portion P. The through conductor constitutes the connection portion 3 or the terminal 5 as described later. However, the resistance heating element 2 may have a special configuration in the main power feeding portion P.

  In a plan view, the positions of both ends (Pa, Pb) of the resistance heating element 2 and the positions and shapes of the paths of the resistance heating element 2 may be set as appropriate. For example, both ends of the resistance heating element 2 are accommodated in the above-described terminal arrangement region 10d.

  In addition, for example, the resistance heating element 2 is a first area Ar1 to a fourth area Ar4 (in the illustrated example, a fan-shaped area; hereinafter, it may be simply referred to as an area Ar) in which the base 1 is divided in the circumferential direction in plan view. Extend in order. The number of divisions of the plurality of areas Ar and the magnitude relationship may be set as appropriate. In the illustrated example, the division is equal division. However, it may not be equally divided. Further, the equal division is four equally in the illustrated example. However, the equal division is not limited to four equal parts, and may be two equal parts, three equal parts, or five equal parts or more.

  The path of the resistance heating element 2 in each of the regions Ar may be set appropriately. In the illustrated example, the resistance heating element 2 extends in a meandering manner (in a meandering manner) in each area Ar. That is, the resistance heating element 2 extends so as to reciprocate in a second direction (vertical direction in FIG. 3) orthogonal to the first direction while shifting the position in a predetermined first direction (horizontal direction in FIG. 3). ing. Further, the resistance heating element 2 has a portion extending along the outer edge of the base 1 in addition to the serpentine portion as described above.

  The material of the resistance heating element 2 is a conductor (for example, metal) that generates heat when current flows. The conductor may be appropriately selected, and is, for example, tungsten (W), molybdenum (Mo), platinum (Pt) or indium (In), or an alloy containing any of these as a main component. Further, the material of the resistance heating element 2 may be obtained by firing a conductive paste containing the above-mentioned metal. That is, the material of the resistance heating element 2 may contain an additive (in another aspect, an inorganic insulator) such as a glass powder and / or a ceramic powder.

  All or part of the resistance heating element 2 may be used also as a sensor element (thermistor) for detecting a temperature. When tungsten or an alloy containing tungsten as a main component is used as the material of the resistance heating element 2, for example, tungsten has a relatively high temperature coefficient of resistance, so that the temperature detection accuracy is improved.

(Branch feeder)
The resistance heating element 2 is one or more branch feeding parts for supplying power to the resistance heating element 2 (a second position between the pair of main power feeding parts P (in another point, in the middle position of the resistance heating element 2) The first branch feed section D1 to the third branch feed section D3 are hereinafter simply referred to as "the branch feed section D" without distinction. Therefore, the resistance heating element 2 can be supplied with power between one main feeding part P and one branch feeding part D, or between two branch feeding parts D. That is, the resistance heating element 2 can be partially supplied with power. In another point of view, the resistance heating element 2 has a first divided section R1 to a fourth divided section R4 divided by the branch feeding section D in a portion between the pair of main feeding sections P.

  Even though the resistance heating element 2 has the branch feeding part D, the resistance heating element 2 has a special configuration (for example, a pad etc.) in the branch feeding part D as in the main feeding part P. The branch feeding part D may have the same configuration as the other most part of the resistance heating element 2. In FIG. 3, as in the case of the main feeding portion P, for convenience, a through conductor (reference numeral omitted, connection portion 3) penetrating the second ceramic layer 1 b is illustrated at the position of the branch feeding portion D.

  However, the resistive heating element 2 may have a special configuration in the branch feeding portion D. For example, the branch power supply part D may be made of a material (for example, a material forming the connection portion 3) different from the material forming the other most part of the resistance heating element 2. That is, from the viewpoint of materials, a plurality of resistance heating elements may be connected in series to constitute the resistance heating element 2. In the description of this embodiment, for convenience, the resistance heating element 2 will be described as one.

  The number of branch feeding parts D (the number of divided sections Rn), the relative position of the branch feeding parts D with respect to the main feeding part P or other branch feeding parts D on the path of the resistance heating element 2 (the length of the divided sections Rn) The position of the branch feeding portion D with respect to the base 1 (the position of the divided section Rn with respect to the base 1) may be set as appropriate. In the illustrated example, it is as follows.

  For example, a total of three branch feeding parts D are provided. Then, on the path of the resistance heating element 2, from the second main feeding part Pb to the first main feeding part Pa, the first branch feeding part D1, the second branch feeding part D2, and the third branch feeding part D3 are sequentially located doing. As a result, four divided sections Rn are provided in total. Then, on the path of the resistance heating element 2, from the second main power supply unit Pb to the first main power supply unit Pa, in order, the first division section R1, the second division section R2, the third division section R3, and the fourth division section R4 is located. The lengths of the plurality of divided sections Rn are, for example, approximately equal to one another. Also, the plurality of divided sections Rn are, for example, substantially divided into a plurality of areas Ar.

(Connection conductor, wiring and terminal)
FIG. 4 is a cross-sectional view taken along line IV-IV of FIG.

  The connection portion 3, the wiring 4 and the terminal 5 shown in FIGS. 2 and 4 are for supplying power to the resistance heating element 2 and are provided on the base 1. The wiring 4 is a hierarchical wiring located in the lower layer with respect to the resistance heating element 2, and connects any one of the plurality of feeding portions (P and D) to any one of the plurality of terminals 5. The connection portion 3 is interposed between the wire 4 and the power feeding portion to contribute to the connection. By providing such a hierarchical wiring, for example, it is possible to connect an arbitrary position (feed portion) of the resistance heating element 2 and the terminal 5 arranged at an arbitrary position.

  More specifically, for example, as described above, in the terminal arrangement region 10d (FIG. 3) which is a part of the region on the center side in plan view of the base 1, the terminal 5 is formed from the lower surface of the base 1. Exposed to the outside of the Then, for example, among the main feeding portion P and the branch feeding portion D, those located outside the terminal arrangement region 10d (in the present embodiment, D1 and D3) are connected to the terminal 5 via the connection portion 3 and the wiring 4 It is done. On the other hand, among the main feeding portion P and the branch feeding portion D, those located in the terminal arrangement region 10d (in this embodiment, Pa, Pb and D2) are directly connected to the terminal 5 without passing through the wiring 4, for example. It is done.

  The connection portion 3 includes, for example, a through conductor penetrating a part of the base 1 (the second ceramic layer 1 b). And it is connected to these feed parts by being located directly under the 1st branch feed part D1 and the 3rd branch feed part D3. In other words, in the inside of the base 1, the connection portion 3 protrudes from the feeding portion of the resistance heating element 2 to the opposite side to the upper surface 10 c of the base 1.

  The wiring 4 is formed of, for example, a conductor pattern located between the second ceramic layer 1 b and the third ceramic layer 1 c. That is, the wiring 4 is embedded in the base 1. The dimensions and shape of the wiring 4 may be set appropriately. In the illustrated example, the wires 4 extend linearly with a substantially constant width. Further, in plan view, the terminal 5 is located in the terminal placement area 10d which is a part of the center side of the base 1, and the first branch feeder D1 and the third branch feeder D3 are located outside the terminal placement area 10d. The wires 4 extend generally in the radial direction of the base 1 in correspondence to what is being done. The wires 4 extend parallel to the top surface 10 c of the base 1.

  Among the plurality of terminals 5, those connected to the wiring 4 are made of, for example, through conductors penetrating the third ceramic layer 1 c. The terminal 5 is connected to the wiring 4 by being located directly below the wiring 4 at an end portion of the wiring 4 opposite to the connection portion 3.

  Among the plurality of terminals 5, those directly connected to the feeding portion (Pa, Pb and D2) without the wiring 4 are, for example, through conductors penetrating the second ceramic layer 1 b and the third ceramic layer 1 c. It is configured. And this terminal 5 is connected to the electric power feeding part (Pa, Pb and D2) by being located directly under the resistance heating element 2. As shown in FIG.

  Although not shown in particular, the terminal 5 may protrude from the lower surface of the base 1 and may have a female screw portion or a male screw portion. Alternatively, the terminal 5 may further include a pad (layered conductor) located on the lower surface of the base 1.

  The material of the connection portion 3, the wiring 4 and the terminal 5 may be an appropriate conductor (for example, metal). For example, these materials are molybdenum (Mo), tungsten (W), tantalum (Ta) or an alloy containing these as main components. Moreover, the material of the connection part 3, the wiring 4, and / or the terminal 5 may be obtained by baking the conductive paste containing the metal as described above. That is, the material of these conductors may contain glass powder and / or ceramic powder. In addition, these materials may be the same as or different from the material of the resistance heating element 2. The surface exposed to the outside of the terminal 5 may be covered with a metal having excellent bonding and / or corrosion resistance.

  The through conductor forming the connection portion 3 (the same applies to the connection conductor 3a described later) and / or the terminal 5 may be similar to, for example, various ones used in the multilayer wiring board. The through conductor may be a conductor filled in a hole formed in the ceramic layer (may be solid) or a conductor formed on the inner peripheral surface in the hole. (May be hollow). However, if it is solid, it is easy to secure the conduction area. The interior of the hollow through conductor may be partially or entirely filled with an insulating material. Also, the through conductor may have a constant diameter or may have a variable diameter (for example, a tapered or reverse tapered shape). The shape of the cross section orthogonal to the penetration direction may be set appropriately, for example, the shape is circular. In the case where the through conductor extends over two or more ceramic layers, the through conductor may be produced by overlapping the conductors penetrating the respective ceramic layers, or two or more ceramic layers. It may be made to penetrate.

  In the connection portion between the through conductor (the connection portion 3 and the terminal 5) and the layered pattern (the resistive heating element 2 and the wiring 4), the penetrating conductor is on the upper surface or the lower surface of the layered pattern It may be connected, or a layered pattern may be connected around the through conductor, and such distinction may not be possible. In the description of the present embodiment, for convenience, in any case, it is conceptually understood that the connection portion 3 and / or the terminal 5 is connected to the upper surface or the lower surface of the resistance heating element 2 and the wiring 4 Do.

(Details of connection (multiple connection conductors))
FIG. 5 is an enlarged perspective view showing the connection portion 3 and the periphery thereof.

  Each connection portion 3 includes, for example, a plurality (three in the illustrated example) of connection conductors 3a. The plurality of connection conductors 3a are arranged along the path of the resistance heating element 2 (in the direction in which the resistance heating element extends), and one feeding portion (D1 or D3 in this embodiment) and one wiring 4 (another) In the point of view, one terminal 5) is connected in parallel. Thereby, the conduction area between the resistance heating element 2 and the wiring 4 is easily secured. Each connection conductor 3a is, for example, a through conductor penetrating the second ceramic layer 1b, as already described as the description of the connection portion 3.

  The shape and dimensions of each connection conductor 3a may be set appropriately. For example, as described above, the through conductor forming the connection conductor 3a may be the same as that used in the multilayer wiring board, and as an example, has a substantially cylindrical shape. Further, the diameter (for example, the maximum diameter or the diameter in the width direction of the resistance heating element 2) of each connection conductor 3a is, for example, substantially equal to the width of the resistance heating element 2. When almost the same, for example, the difference between the two is 10% or less of the width of the resistance heating element 2. In other words, the diameter of the connection conductor 3 a is 0.9 times or more and 1.1 times or less the width of the resistance heating element 2. Of course, the diameter of the connection conductor 3 a may not be equal to the width of the resistance heating element 2. When an example of a dimension is shown, for example, the width of the resistance heating element 2 is 1 mm or more and 10 mm or less. Also, for example, the diameter of the connection conductor 3a (cylindrical shape) is 1 mm or more and 7 mm or less.

  The number and relative position of the plurality of connection conductors 3a may be set as appropriate. The number of connection conductors 3a may be two or four or more, unlike the illustrated example. The relative positions of the plurality of connection conductors 3a corresponding to one feeding portion are defined by the path of the resistive heating element 2 because the plurality of connecting conductors 3a are arranged along the path of the resistive heating element 2. In the illustrated example, since the feeding portion (D1 or D3) is located in a portion where the resistance heating element 2 is a circular arc having a relatively large radius of curvature, the plurality of connection conductors 3a are arranged in a substantially linear shape It is done. Depending on the shape of the path of the resistance heating element 2 and the position of the feeding portion, the three connection conductors 3a are arranged in a triangular shape, for example. The intervals of the plurality of connection conductors 3a corresponding to one power feeding unit may be set as appropriate. Also, the interval may be relatively narrow. Even when the plurality of connection conductors 3a are short-circuited, no electrical inconvenience occurs.

  The shape of the connection portion 3 of the wiring 4 at the connection portion may be appropriately set so that connection with the plurality of connection conductors 3 a is possible. In the illustrated example, the arrangement of the plurality of connection conductors 3a is substantially along the width direction of the wiring 4 and the length of the arrangement of the plurality of connection conductors 3a is larger than the width of the wiring 4 The connection portion between the wiring 4 and the connection portion 3 has two branch portions 4 a extending on both sides in the width direction. Note that, depending on the arrangement of the plurality of connection conductors 3a, such a branch portion 4a may not be provided, or the branch portion 4a may extend in an appropriate direction. Moreover, you may form a pad-like part instead of providing the branch part 4a.

(Relational relationship between cross sections of each part)
The cross-sectional areas of the terminals 5, the wires 4, the connection portions 3 (the plurality of connection conductors 3a), and the resistance heating element 2 connected in series with one another may be set as appropriate. In the description of the embodiments, the term “cross-sectional area” of these conductors refers to the area of the cross section of these conductors unless otherwise noted. The cross section of the terminal 5 or the connection portion 3 is a cross section parallel to the upper surface 10c, and the cross sectional area of the wiring 4 or the resistance heating element 2 is a cross section orthogonal to the extending direction of these conductors.

  When the above conductors are listed in descending order of cross-sectional area, for example, the terminal 5, the wiring 4, the connection portion 3 (the total cross-sectional area of the plurality of connection conductors 3a) and the resistance heating element 2 are obtained. That is, the cross-sectional area is smaller toward the resistance heating element 2 side. By doing this, for example, it is easy to reduce heat generation on the way from the terminal 5 to the resistance heating element 2. However, the cross-sectional areas of these conductors do not have to be in such a relative relationship.

  In addition, in each conductor, when the cross-sectional area changes with positions, for example, the comparison may be made with the smallest cross-sectional area (the part that is easily heated in another viewpoint). For example, in the example of FIG. 5, the wire 4 is extended in width by having two branches 4a at the end, while the wire 4 mostly extends with a fixed width. In this case, the cross-sectional area of the portion extending at a constant width may be compared with the cross-sectional area of the other conductor.

  The relative relationship between the cross-sectional areas may be realized by setting the dimension in any direction of the cross section of each conductor. For example, it is as follows.

  As described above, the connection conductor 3 a is formed in a substantially cylindrical shape, and the diameter thereof is made equal to the width of the resistance heating element 2. On the other hand, the resistance heating element 2 is a layer whose thickness is smaller than its width. Thereby, the cross-sectional area of each connection conductor 3 a tends to be larger than the cross-sectional area of the resistance heating element 2. Then, the total of the cross-sectional areas of the plurality of connection conductors 3 a (constituting one connection portion 3) is larger than the cross-sectional area of the resistance heating element 2. For example, the total cross-sectional area of the plurality of connection conductors 3a may be twice or more or five times or more of the cross-sectional area of the resistance heating element 2, or approximately ten times the cross-sectional area of the resistance heating element 2 It is also good.

  The wiring 4 has a cross-sectional area secured by, for example, being made wider than the diameter of the connection conductor 3a. As a result, it is made larger than the sum of the cross-sectional areas of the plurality of connection conductors 3a (constituting one connection portion 3). In FIG. 5, for convenience of illustration, the wiring 4 and the connection conductor 3a are shown at a dimensional ratio in which the cross-sectional area of the wiring 4 is smaller than the sum of the cross-sectional areas of the plurality of connection conductors 3a.

  The terminal 5 has, for example, a cylindrical shape, and the diameter is equal to the width of the wiring 4. On the other hand, the wiring 4 is a layer whose thickness is smaller than its width. Thereby, the cross-sectional area of the terminal 5 is made larger than the cross-sectional area of the wiring 4.

  When the wiring 4 and the resistance heating element 2 are compared, the cross-sectional area of the wiring 4 is, for example, at least twice or at least five times the cross-sectional area of the resistance heating element 2. The thickness of the wiring 4 may be thinner, equal to, or larger than that of the resistance heating element 2. When the thickness of the wiring 4 is substantially equal to the thickness of the resistance heating element 2, for example, the difference between the two is 10% or less of the thickness of the resistance heating element 2. As an example of dimensions, the width of the resistance heating element 2 is 1 mm or more and 10 mm or less, the thickness of the resistance heating element 2 is 10 μm or more and 150 μm or less, the width of the wiring 4 is about 10 times that of the resistance heating element 2 and the thickness of the wiring 4 The length is approximately the same as the thickness of the resistance heating element 2 (the cross sectional area of the wiring 4 is about 10 times the cross sectional area of the resistance heating element 2).

  The terminals 5 directly connected to the feeding part (Pa, Pb and D2) without the wiring 4 are, for example, as shown in FIG. 5 except for the length in the axial direction (thickness direction of the base 1). It has the same shape and dimensions as the terminal 5 shown.

(Drive)
The drive device 50 shown in FIG. 1 is configured to include, for example, a power supply circuit, a computer, etc., and converts the power from the commercial power supply into AC power and / or DC power of an appropriate voltage to Supply to terminal 5) of The computer is configured by, for example, an integrated circuit (IC) and / or a personal computer. The computer also includes, for example, a CPU, a ROM, a RAM, and an external storage device, and the CPU executes programs stored in the ROM or the like to configure various functional units such as a control unit. The control unit or the like may be configured by combining circuits that perform predetermined arithmetic processing. The processing performed by the drive device 50 may be digital processing or analog processing.

(Control method)
FIG. 6A is a schematic view showing an outline of a configuration of a control system in the heater system 100. As shown in FIG.

  In this drawing, the resistance heating element 2 is schematically shown by the white line extending in the left and right direction in the upper part of the paper surface. The both ends are a pair of main feed parts P, and a plurality of branch feed parts D are located in the middle. The symbols or figures around the resistance heating element 2 schematically show the components of the driving device 50.

  The drive device 50 includes, for example, a main drive unit 51 and an additional drive unit 52. The main drive unit 51 supplies main power (first power, main current) between the pair of main power supply units P. That is, the main drive unit 51 supplies main power to the entire resistance heating element 2. In addition, the additional driving unit 52 separates additional power (second power, additional current) between adjacent ones of the plurality of feeding units (P and D) on the path of the resistance heating element 2, for example. Supply to That is, the additional drive unit 52 individually supplies the additional power to the plurality of divided sections Rn.

  Therefore, in the resistance heating element 2, an additional current partially flows while being superimposed on the main current flowing in the whole. As a result, for example, temperature control suitable for the region Ar can be performed for each region Ar of the heater main body 10a while realizing most of the heat generated by the heater main body 10a by the main power. As a result, for example, it is facilitated to make the temperature distribution in the heater main body 10 a uniform, and conversely, to generate a desired temperature gradient in the heater main body 10 a.

  The main power may be either DC power or AC power. The additional power may be either DC power or AC power. For example, the main power is direct current power, and the additional power is alternating current power. Alternatively, the main power is alternating current power, and the additional power is alternating current power having a frequency higher than that of the main power.

  FIG. 6B is a view schematically showing an example of temperature control in the heater system 100. As shown in FIG. In this figure, the horizontal axis shows time, and the vertical axis shows temperature.

  In the illustrated example, for example, the drive device 50 controls the main power and the additional power so that the temperature distribution of the heater main body 10a becomes uniform, and the temperature converges to a constant target temperature tr0 over time. . Specifically, for example, the driving device 50 controls the main power so that the temperature of the heater main body 10a becomes the set temperature tra lower than the target temperature tr0 by heating by the main power. Further, the drive device 50 controls the additional power for each divided section Rn such that the temperature of each divided section Rn (region Ar) becomes the target temperature tr0. As a result, the temperature of each divided section Rn rises from the set temperature tra by a temperature rise tadd due to heating by the additional power. As a result, the temperature of each divided section Rn converges to the target temperature tr0.

  Since FIG. 6B is a schematic view, the state in which the temperature obtained by adding the temperature tr0 and the temperature increase tadd vibrates with respect to the target temperature tr0 is relatively large and is expressed by a rectangular wave. ing. In practice, such vibrations may be reduced by employing a sophisticated control scheme such as proportional integral differential (PID) control.

  Returning to FIG. 6A, the drive device 50 has, for example, the first insulating transformer T1 to the fourth insulating transformer T4 (hereinafter, simply referred to as "insulating transformer T", which may not be distinguished from one another). It may be done. The insulation transformer T is provided, for example, for each divided section Rn, and mediates supply of AC power as additional power from the additional drive unit 52 to the divided section Rn. By providing such an insulation transformer T, for example, when the component (noise) having a frequency higher than the frequency of the AC power is included in the additional power, the component may flow to the resistance heating element 2. It can be reduced.

  In addition, the drive device 50 may have, for example, the first capacitor C1 to the fourth capacitor C4 (hereinafter, simply referred to as “capacitor C” and may not be distinguished from one another). The capacitor C is provided, for example, for each divided section Rn, and is connected in series between the additional drive unit 52 and the divided section Rn. By providing such a capacitor C, for example, it is possible to relatively reduce the possibility that the main current, which is a direct current or an alternating current having a relatively low frequency, may flow to the additional drive unit 52 side. An additional current which is an alternating current having a high frequency can be supplied to the resistance heating element 2.

(Method of manufacturing heater)
The method of manufacturing the heater 10 is, for example, as follows.

  First, ceramic green sheets to be the first ceramic layer 1a to the third ceramic layer 1c are prepared. The green sheet may be formed, for example, by forming a slurry into a sheet by a doctor blade method, or the slurry is spray dried by a spray granulation method (spray dry method) to granulate, and a roll compaction method is used. It may be formed by The green sheet is formed to have a substantially constant thickness. For the slurry, for example, the main component material is prepared so that aluminum oxide, aluminum nitride, silicon nitride or silicon carbide is a main component, and a predetermined amount of a sintering aid, a binder, a solvent, a dispersing agent, etc. is added thereto. Made by mixing.

  Next, the green sheet is subjected to laser processing and / or punching using a mold so as to have a desired shape. At this time, for example, a hole in which the connection portion 3 and the terminal 5 are disposed is formed.

  Next, a metal paste to be a conductor such as the resistance heating element 2, the connection portion 3, the wiring 4 and the terminal 5 is disposed on the green sheet by an appropriate method such as screen printing. For example, a metal paste to be the resistance heating element 2 is disposed on the upper surface of the green sheet to be the second ceramic layer 1b (or the lower surface of the green sheet to be the first ceramic layer 1a). A metal paste to be the wiring 4 is disposed on the upper surface of the green sheet to be the third ceramic layer 1c (or the lower surface of the green sheet to be the second ceramic layer 1b). The metal paste used as the connection part 3 is filled in the hole formed in the green sheet used as the 2nd ceramic layer 1b. The metal paste used as the terminal 5 is filled in the hole formed in the green sheet used as the 3rd ceramic layer 1c. The metal paste contains, for example, a ceramic powder such as AIN. The metal paste to be the resistance heating element 2 and / or the wiring 4 is applied by a known method such as screen printing, for example.

  The material to be the resistance heating element 2 and / or the wiring 4 may be a conductive sheet containing a conductive material and a ceramic powder. The conductive sheet is sandwiched by the green sheets, for example, in the production of a laminate of green sheets described later. Alternatively, a groove may be cut in the green sheet, and the conductive sheet may be disposed in the groove.

  Moreover, the material used as the connection part 3 and / or the terminal 5 may be the same as that of the connection part 3 and / or the terminal 5 after completion. That is, the material may be solid and columnar metal (metal bulk material). In this case, the holes in which the connection portions 3 and the terminals 5 are disposed have diameters and penetrations larger than the diameter and axial length of the metal bulk material in consideration of the difference in shrinkage ratio between the green sheet and the metal bulk material in firing described later. The length may be increased.

  Next, the green sheets are laminated to prepare a laminate of green sheets. In addition, what is necessary is just to use the slurry mentioned above as a bonding material used when laminating | stacking a sheet | seat.

  And the laminated body of a green sheet is baked according to the baking conditions of a main component. Thereby, the sintered compact (base 1) which provided resistance heating element 2, connection part 3, wiring 4, and terminal 5 inside can be obtained. In addition, the base | substrate 1 (1st ceramic layer 1a-3rd ceramic layer 1c) shrink | contracts in the case of baking. In addition, various conductors disposed on the substrate 1 also contract due to the addition of the ceramic powder.

  A table or a table for plasma processing by sandwiching a metal paste, a metal plate or a metal mesh to be a plasma processing electrode or an electrostatic chuck electrode in addition to the resistance heating element 2, the connection portion 3, the wiring 4 and the terminal 5 during lamination. An electrostatic chuck can also be made.

  As described above, in the present embodiment, the heater 10 includes the base 1, the resistance heating element 2, the plurality of connection conductors 3 a, and the terminals 5. The substrate 1 has a predetermined surface (upper surface 10c) and has an insulating property. The resistance heating element 2 extends along the upper surface 10c on the upper surface 10c or in the substrate 1 (in the present embodiment, in the substrate 1). The plurality of connection conductors 3a each include a portion (all of the connection conductors 3a in this embodiment) extending from the resistance heating element 2 to the opposite side to the side facing the upper surface 10c. The (one) terminal 5 is exposed to the side opposite to the side on which the upper surface 10c faces, and the plurality of connection conductors 3a are electrically connected in parallel to one another. The plurality of connection conductors 3 a are arranged along the path of the resistive heating element 2 in the extending direction of the resistive heating element 2.

  Therefore, for example, compared with the case where the resistance heating element 2 and the terminal 5 are connected by one through conductor (connection conductor 3a), the conduction area between the resistance heating element 2 and the connection portion 3 can be increased. By increasing the conduction area, for example, the risk of disconnection can be reduced, and the risk of heat generation at the connection portion 3 can be reduced.

  From another viewpoint, for example, in order to secure the conduction area, the need to locally increase the width of the resistance heating element 2 at the feeding portion or to increase the diameter of the connection conductor 3a is reduced. As a result, for example, it is possible to closely arrange the resistance heating elements 2 by shortening the center-to-center distance between adjacent portions of the resistance heating elements 2 over the entire resistance heating elements 2. In other words, even if the resistance heating elements 2 are densely arranged, the possibility of a short circuit between the feeding portion of the resistance heating elements 2 and the portion which is not the feeding portion of the resistance heating elements 2 is reduced. Such an effect is particularly effective when the branch feeding portion D is provided not only at the end of the resistance heating element 2 but also at the middle position of the resistance heating element 2 as in the present embodiment.

  Also, for example, instead of forming the through conductor in a long and thin shape along the resistance heating element 2 in plan view, the plurality of connection conductors 3 a are arranged along the resistance heating element 2, and thus conventionally known connection conductors 3 a. An approximately cylindrical through conductor can be used.

  Further, in the present embodiment, the total area of the cross sections orthogonal to the extending direction of the plurality of connection conductors 3a (constituting one connection portion 3) is the area of the cross section orthogonal to the extending direction of the resistance heating element 2 Greater than.

  Therefore, for example, the amount of heat generated in the plurality of connection conductors 3a can be reduced. As a result, for example, the possibility that the temperature rises locally near the feeding point of the resistance heating element 2 is reduced. That is, the calorific value on the upper surface 10c is equalized.

  Further, in the present embodiment, the area of the cross section orthogonal to the extending direction of the wiring pattern (in the present embodiment, the wiring 4) is larger than the total area of the cross sections orthogonal to the penetrating direction of the plurality of connection conductors 3a.

  Therefore, for example, the amount of heat generated in the wiring 4 can be reduced. As a result, for example, the heat generation on the lower surface side of the substrate 1 which does not directly contribute to the heating of the wafer is suppressed. As a result, wasteful consumption of power can be reduced.

  In the present embodiment, the diameter of at least one of the plurality of connection conductors 3a in the width direction of the resistance heating element 2 is 0.9 times or more and 1.1 times or less the width of the resistance heating element 2 .

  That is, the diameter of the connection conductor 3 a can be as close as possible to the width of the resistance heating element 2. As a result, for example, compared with the case where the diameter of the connection conductor 3a is smaller than the width of the resistance heating element 2, the effect of increasing the conduction area without locally increasing the width of the resistance heating element 2 described above is improved. Do. Further, for example, compared with the case where the diameter of the connection conductor 3a is larger than the width of the resistance heating element 2, the possibility that the connection conductor 3a and a portion other than the feeding portion of the resistance heating element 2 are shorted is reduced. .

Second Embodiment
(Structure of heater)
FIG. 7A is an enlarged perspective view showing a part of the heater 210 according to the second embodiment, and corresponds to a part on the right side of the drawing of FIG. FIG.7 (b) is sectional drawing in the VIIb-VIIb line | wire of FIG. 7 (a).

  The heater 210 basically differs from the heater 10 of the first embodiment only in the configuration of the connection conductor 203 a of the connection portion 203. The other configuration may be the same as the configuration of the first embodiment. In the illustrated example, unlike the example of FIG. 5, the wiring 4 has a constant width up to the plurality of connection conductors 203a.

  The connecting conductor 203 a is different from the connecting conductor 3 a of the first embodiment in that the connecting conductor 203 a passes through the resistance heating element 2 and the wiring 4. More specifically, the upper end of the connection conductor 3a, for example, penetrates the resistance heating element 2 and protrudes above the resistance heating element 2 (embedded in the first ceramic layer 1a). The lower end of the connection conductor 3a penetrates, for example, the wiring 4 and protrudes below the wiring 4 (embedded in the third ceramic layer 1c). The amount of protrusion may be set appropriately.

  The material of the connection conductor 203a is, for example, a pure metal or an alloy containing only a metal element. In another aspect, in the first embodiment, it is described that the material of the connection conductor 3a may include ceramic powder and / or glass powder (inorganic insulator), but the material of the connection conductor 203a is It is considered not to contain such inorganic insulators. The metal element of the pure metal or the metal element of the alloy may be the same as or different from the metal element of the resistance heating element 2, the wiring 4 and / or the terminal 5. It is also good. The metal element of the pure metal or the main component of the alloy is, for example, tungsten (W) or molybdenum (Mo).

  In the first embodiment, in the connection portion between the through conductor (connection conductor 3a or terminal 5) and the layered pattern (resistance heating element 2 or wiring 4), the upper surface of the layered pattern is viewed from the viewpoint of material or manufacturing process Alternatively, it has been described that the through conductor may be connected to the lower surface, and the layered pattern may be connected to the periphery of the through conductor. In the present embodiment, the layered pattern (the resistance heating element 2 or the wiring 4) is connected, for example, around the connection conductor 203a.

  The dimensions of the connection conductor 203a may be the same as the dimensions of the connection conductor 3a of the first embodiment except for the length (vertical direction). For example, the diameter of the connection conductor 203a may be 0.9 times or more and 1.1 times or less the width of the resistance heating element 2, or may be larger or smaller than this. In the illustrated example, the diameter of the connection conductor 203 a is smaller than the width of the resistance heating element 2, and the connection conductor 203 a is inserted into a hole (reference numeral omitted) formed in the resistance heating element 2.

  The diameter of the connection conductor 203 a may be equal to or greater than the width of the resistance heating element 2, and may not be inserted into a hole (reference numeral omitted) formed in the resistance heating element 2. That is, the connection conductor 203 a may be provided to divide the resistance heating element 2. Also in this embodiment, the connection conductor 203 a is expressed as penetrating the resistance heating element 2. Similarly, even when a notch is formed in a part of the outer edge of the wiring 4 by the connection conductor 203 a, the connection conductor 203 a is expressed as penetrating the wiring 4.

(Method of manufacturing heater)
FIGS. 8A and 8B are cross-sectional views for explaining the method of manufacturing the heater 210, and correspond to FIG. 7B. In FIG. 8B, hatching of the first to third ceramic layers 1a to 1c is omitted. Further, in FIGS. 8A and 8B, the same reference numerals are used for the members even if the characteristics, dimensions, and the like of the members change with the progress of the manufacturing process.

  The method of manufacturing the heater 210 may be the same as that of the first embodiment, for example, except for the material used for the connection conductor 203a. Specifically, it is as follows.

  As shown to Fig.8 (a), the through-hole (code | symbol abbreviation | omission) in which the connection conductor 203a is provided similarly to 1st Embodiment is formed in the ceramic green sheet used as the 2nd ceramic layer 1b. The connection conductor 203a is disposed in the through hole.

  In the first embodiment, a conductive paste to which ceramic powder (inorganic insulator) such as AIN is added is used as a material of the connection conductor 3a disposed in the through hole. On the other hand, the material of the connection conductor 203a of the present embodiment is one to which no such ceramic powder is added.

  For example, the connection conductor 203a disposed in the through hole is the same as the connection conductor 203a in the heater 210 after completion. In other words, the material disposed in the through hole is a solid and columnar metal (metal bulk material). The shape and size thereof are, for example, approximately the same as the shape and size of the through holes formed in the ceramic green sheet to be the second ceramic layer 1b. A gap may be formed between the outer peripheral surface of the connection conductor 203a and the inner peripheral surface of the through hole. The gap may be set, for example, in consideration of the difference in shrinkage rate between the non-shrinkable metal bulk material and the green sheet.

  Also, for example, as a material of the connection conductor 203a, a molten metal (pure metal or an alloy consisting of only a metal element) may be filled in the through hole of the ceramic green sheet. Then, before the ceramic green sheet is fired, the metal may be solidified to form the connection conductor 203a. A conductive paste containing metal powder and a resin solution and not containing an inorganic insulator such as ceramic powder may be filled in the through holes of the ceramic green sheet as the material of the connection conductor 203a.

  When the connection conductor 203a (or the material thereof) is disposed in the through hole of the ceramic green sheet to be the second ceramic layer 1b, the ceramic green sheets to be the first ceramic layer 1a to the third ceramic layer 1c are laminated. Thereafter, the laminate of the ceramic green sheets is fired.

  As shown by the arrows in FIG. 8B, the laminated body (base 1) of the ceramic green sheets shrinks in the thickness direction and in the planar direction by firing. Further, the conductive paste (the resistance heating element 2 and the wiring 4) to which the ceramic powder is added shrinks in the same manner. On the other hand, the connection conductor 203a is, for example, a metal bulk material and is not a conductive paste to which a ceramic powder is added.

  Therefore, the connection conductor 203 a penetrates the resistance heating element 2 and the wiring 4 by contraction in the thickness direction of the base 1. Furthermore, the connection conductor 203a protrudes into the first ceramic layer 1a and the third ceramic layer 1c.

  Further, when contraction of base 1, resistance heating element 2 and wiring 4 further progresses from the state where connection conductor 203a penetrates resistance heating element 2 and wiring 4, connection conductor 203a is planarized by resistance heating element 2 and wiring 4. Tighten in the direction. Thereby, the conduction between the outer peripheral surface of the connection conductor 203a and the layered pattern (the resistance heating element 2 and the wiring 4) is surely made.

  In the example shown in FIG. 8B, the upper end surface and the lower end surface of the connection conductor 203a are constituted by portions punched out by the connection conductor 203a of the conductive paste to be the resistance heating element 2 and the wiring 4. The portion may be captured as a separate member from the connection conductor 203a, or may be captured as a part of the connection conductor 203a. In another aspect, the connection conductor 203a may be considered to be made of an alloy containing only pure metals or metal elements, or may be considered to be configured to contain other materials. In the ceramic green sheet, the conductive paste to be the resistance heating element 2 and the wiring 4 may not be provided in the area overlapping the connection conductor 203a, and the above-mentioned punched out part may not be formed.

  Although not particularly illustrated, a part or all of the terminals 5 may be configured similarly to the connection conductor 203a. For example, the terminal 5 may be composed of a pure metal or an alloy containing only a metal element. The metal element of the pure metal or the main component of the alloy may be tungsten or molybdenum. The upper end of the terminal 5 (the terminal 5 corresponding to the feeding part D1 or D3) connected to the wiring 4 may penetrate the wiring 4. The upper end of the terminal 5 (the terminal 5 corresponding to the feeding part Pa, Pb or D 2) directly connected to the resistance heating element 2 may penetrate the resistance heating element 2. Further, the lower end of the terminal 5 may protrude from the lower surface of the base 1.

(Modified Example of Manufacturing Method of Second Embodiment)
FIG. 9A is a cross-sectional view showing a modified example of the method of manufacturing the heater 210, and corresponds to FIG. That is, FIG. 9A shows a part of the heater 210 before firing.

  As shown to this figure, the recessed part 1r may be formed in the position which overlaps with the connection conductor 203a in the surface at the side of the connection conductor 203a of the ceramic green sheet used as the 1st ceramic layer 1a and the 3rd ceramic layer 1c.

  The recess 1 r has, for example, a cross-sectional shape parallel to the upper surface 10 c substantially in a constant shape across the depth direction (vertical direction). The planar shape (including the dimensions) of the recess 1 r is set, for example, to be approximately equal to that of the connection conductor 203 a after firing. However, the planar shape of the recess 1 r may be set to be smaller or larger than the connecting conductor 203 a after firing. The total depth of the two recesses 1r is, for example, equal to the total depth of the connection conductor 203a protruding into the first ceramic layer 1a and the third ceramic layer 1c after firing. However, the former may be smaller or larger than the latter.

  By providing such a recess 1r, the force with which the connection conductor 203a presses the first ceramic layer 1a and / or the third ceramic layer 1c in the vertical direction is reduced when the substrate 1 contracts with firing. Or eliminated. Thereby, for example, the possibility that the flatness of the upper surface 10c of the substrate 1 may be reduced can be reduced.

  Note that the same conductive paste as the conductive paste used to form the resistance heating element 2 and the wiring 4 may be disposed in part or all of the recess 1 r. And the part integrally formed with the resistance heating element 2 and the wiring 4 may be formed in the upper end and lower end of the connection conductor 203a. In addition, the recess 1 r may be formed in only one of the first ceramic layer 1 a and the third ceramic layer 1 c.

(Another modification of the manufacturing method of the second embodiment)
FIG. 9B is a cross-sectional view showing another modification of the method of manufacturing the heater 210, and corresponds to FIG. 8A. That is, FIG. 9 (b) shows a part of the heater 210 before firing.

  In FIG. 9B, the metal 203aa is the same as the connection conductor 203a of FIG. 8A, and is a solid and columnar metal (metal bulk material). In this case, the conductive paste 203ab may be disposed between the metal 203aa and the through hole. The conductive paste 203ab is, for example, the same material as the conductive paste to be the resistance heating element 2 and / or the wiring 4. And connection conductor 203a may be constituted by metal 203aa and conductive paste 203ab.

  In this case, for example, the connection conductor 203 a has a portion integrally formed with the resistance heating element 2 and / or the wiring 4. As a result, conduction between the connection conductor 203a and the layered pattern (the resistance heating element 2 and / or the wiring 4) can be ensured.

  In the above description, the portion formed of the conductive paste 203ab is also regarded as a part of the connection conductor 203a, but the portion formed of only the metal 203aa may be regarded as the connection conductor 203a.

  As described above, in the present embodiment, as in the first embodiment, the plurality of connection conductors 203 a are arranged in the extending direction of the resistance heating element 2 along the path of the resistance heating element 2. Therefore, the same effect as that of the first embodiment is achieved. For example, the conduction area between the resistance heating element 2 and the connecting portion 3 can be increased without increasing the width of the resistance heating element 2.

  Further, in the present embodiment, the base 1 is made of ceramic. At least one of the plurality of connection conductors 203a (in one connection portion 3) is made of a pure metal or an alloy containing only a metal element (an alloy not containing a ceramic powder).

  Therefore, for example, as described with reference to FIG. 8B, when fired, it is a metal compared to the ceramic green sheet (base 1) and the conductive paste (resistance heating element 2 and wiring 4). The connection conductor 203a (for example, a metal bulk material) does not shrink. As a result, the connection conductor 203 a can be tightened by the resistance heating element 2 and / or the wiring 4 to reliably conduct the connection conductor 203 a. In addition, since the connection conductor 203a does not contain, for example, an inorganic insulator, the resistance value can be easily reduced. As a result, the amount of heat generated in the connecting conductor 203a can be reduced.

  Further, in the present embodiment, the metal element of the above pure metal or the metal element of the main component of the alloy is tungsten or molybdenum.

  Here, tungsten or molybdenum can be used as a material of the resistance heating element 2. Therefore, for example, when the main component of the material of the resistance heating element 2 is the same as the main component of the connection conductor 203a, the improvement of the bonding strength between the resistance heating element 2 and the connection conductor 203a and / or the reduction of the electrical resistance There is expected.

  Further, in the present embodiment, at least one of the plurality of connection conductors 203 a (in one connection portion 3) penetrates the resistance heating element 2.

  Therefore, for example, the upper surface of the connection conductor 203a may be located below the resistance heating element 2, and the possibility that the both will not be conducted may be reduced. Further, as described with reference to FIG. 8 (b), the connection conductor 203a can be tightened by the resistance heating element 2 which shrinks during firing, and both can be reliably conducted. Further, for example, by electrically conducting the two, it is possible to reduce the possibility that the resistance value is increased at the junction of the two, and, consequently, to reduce the possibility of locally increasing the temperature in the vicinity of the feeding point of the resistance heating element 2 it can. That is, the calorific value on the upper surface 10c is equalized.

  Further, in the present embodiment, at least one of the plurality of connection conductors 203 a (in one connection portion 3) penetrates the wiring 4.

  Therefore, for example, the possibility that the lower surface of the connection conductor 203a is located above the wiring 4 and the problem that the both are not conducted may be reduced. Further, as described with reference to FIG. 8B, the connection conductor 203a can be tightened by the wiring 4 that shrinks during firing, and both can be reliably conducted. Further, for example, by reliably establishing electrical continuity between the two, it is possible to reduce the possibility that the resistance value will increase at the joint portion between the two, and in turn, the heat generation on the lower surface side of the substrate 1 not directly contributing to the heating of the wafer is suppressed. . That is, wasteful consumption of power can be reduced.

<Various modifications>
FIG. 10A to FIG. 11B are schematic views showing various modifications. Here, the connection conductor 3a of the first embodiment is taken as an example of the connection conductor. However, the following modification may be applied to the second embodiment. Also, the following modifications may be combined with one another as appropriate.

  FIG. 10A is an enlarged perspective view of the periphery of the terminal 5 in the feeding part Pa, Pb or D2.

  In the description of the first embodiment, among the plurality of terminals 5, one directly connected to the feeding portion Pa, Pb or D2 is constituted by a through conductor penetrating the second ceramic layer 1b and the third ceramic layer 1c. As said that. In other words, it has been described that the plurality of connection conductors 3a (connection portions 3) do not intervene between the terminal 5 and the feeding portion Pa, Pb or D2.

  However, as shown in FIG. 10 (a), even if the plurality of connection conductors 3a are provided in parallel with each other on the terminal 5, and the terminals 5 and the resistive heating element 2 are connected by the plurality of connection conductors 3a. Good.

  In addition, when this modification is applied to 2nd Embodiment, the terminal 5 may be formed with an electrically conductive paste, for example unlike the connection conductor 203a. In this case, the lower end of the connection conductor 203 a may bite into the terminal 5. Also, conversely to the above, the terminal 5 may be made of a pure metal or an alloy containing only a metal element, similarly to the connection conductor 203a.

  10B and 10C are plan views of the configuration from the terminal 5 to the connection conductor 3a as viewed from below.

  In the description of the first embodiment, it was mentioned that the wiring 4 may not be provided with the branch 4 a. Further, in the description of the second embodiment, the aspect in which the wiring 4 extends with a constant width in the vicinity of the plurality of connection conductors 203a is exemplified. Furthermore, as shown in FIG. 10B, the wiring 4 may extend from the terminal 5 to the plurality of connection conductors 203a with a constant width. In this case, the cross-sectional area is not reduced from the terminal 5 to the plurality of connection conductors 203a, and thus unnecessary heat generation can be reduced.

  Further, as shown in FIG. 10C, one terminal 5 and a plurality of connection conductors 3a electrically connected in parallel to the terminal 5 are separately connected by a plurality of wirings 304a. It may be done. In this case, for example, as compared with the case of connection by one wiring 4, it is possible to disperse the stress caused due to the thermal expansion difference between the base 1 and the wiring 304a. As a result, for example, the risk of disconnection or the like can be reduced. Note that the resistance value of one wire 4 can be easily reduced as compared to the plurality of wires 304 a.

  In the illustrated example, the number of the plurality of wires 304a is the same as the number of the connection conductors 3a, and they are connected one-to-one (individually). However, the number of the plurality of wires 304 a may be smaller than the number of connection conductors 3 a.

  The wiring 4 and the plurality of wirings 304 a have the same function as each other in that the plurality of connection conductors 3 a are connected in parallel to one terminal 5. Therefore, a wiring pattern is defined as a term of the upper concept of the wiring 4 and the plurality of wirings 304 a. For example, in FIG. 10B, the wiring pattern (reference numeral omitted) is made of the wiring 4. In FIG. 10C, the wiring pattern 304 is composed of a plurality of wirings 304a.

  The cross-sectional area orthogonal to the extending direction of the wiring pattern 304 may be specified, for example, by the sum of the cross-sectional areas of the plurality of wires 304 a in the extending direction. The cross-sectional area of the plurality of wires 304 a may be, for example, the minimum value of each wire 304 a. The position of the cross section having the minimum cross-sectional area and the direction of the normal are not necessarily the same among the plurality of wirings 304 a. The sum of the cross-sectional areas of the plurality of branches 4a may be specified as well.

  11 (a) and 11 (b) are cross-sectional views showing the configuration of the heater according to the modification, and correspond to FIG.

  In the embodiment, the resistance heating element 2 is embedded in the substrate 1 made of ceramic. However, as in the heater 410 shown in FIG. 11A, the resistance heating element 2 may be located on the upper surface of the base 401 made of ceramic.

In the illustrated example, the resistance heating element 2 is covered with a covering layer 461 made of an insulating material (for example, an inorganic insulating material such as Y ₂ O ₃ , CaO, MgO, Al ₂ O ₃ , SiO ₂ ) different from the base 401. ing. In this case, the whole of the substrate 401 and the covering layer 461 may be defined as a substrate, and it may be understood that the resistance heating element 2 is embedded in the substrate.

  In the embodiment, the wiring 4 is embedded in the substrate 1 made of ceramic. However, as in the heater 510 shown in FIG. 11B, the wiring 4 may be located on the surface (lower surface) of the substrate 501 made of ceramic.

In the illustrated example, the wiring 4 is made of an insulating material different from the base 501 (for example, an organic insulating material such as a solder resist, or an inorganic insulating material such as Y ₂ O ₃ , CaO, MgO, Al ₂ O ₃ , or SiO ₂ ). Is covered by the covering layer 507. In this case, the whole of the substrate 501 and the covering layer 507 may be defined as a substrate, and it may be considered that the wiring 4 is embedded in the substrate.

  Further, with reference to FIG. 11B, in another aspect, the end of the wiring 4 may be shared with the terminal 5. Note that the portion other than the portion functioning as the terminal 5 may be defined as the wiring 4 without being considered to be shared. In FIG. 11B, the portion of the wiring 4 exposed from the covering layer 507 is the portion to be the terminal 5.

<Example of application>
FIG. 12A is a view showing an application example to which the heater system of the present disclosure is applied. FIG. 12A shows a state in which the heater 30 according to the present disclosure is provided in the chamber 25 of the semiconductor manufacturing apparatus. A wafer 40 as an object to be heated is mounted on the upper surface of the heater 30.

  FIG. 12 (b) is a schematic view showing the configuration of the heater 30. The heater 30 has, for example, a configuration in which an electrode 12 or the like is added to the same configuration as any of the heaters according to the various embodiments or the modifications described above. The heater 30 may have the same configuration as any of the heaters according to various embodiments or modifications.

  The electrode 12 is, for example, a plasma processing electrode (for example, an RF (Radio Frequency) electrode). In this case, a system including the heater 30, the driving device 50, and a driving device (not shown) for applying a voltage to the plasma processing electrode constitutes a plasma processing device.

  The electrode 12 is, for example, an electrostatic chuck electrode. In this case, the heater 30 constitutes an electrostatic chuck, and a system including the heater 30, the driving device 50, and a driving device (not shown) for applying a voltage to the electrostatic chuck electrode constitutes a suction device.

  Also, the heater 30 may be applied to a chemical vapor deposition (CVD) process in semiconductor manufacturing.

  The technology according to the present disclosure is not limited to the above-described embodiment, modification, and the like, and may be implemented in various aspects.

  In the embodiment, the feeding parts (D1 to D3) are disposed in the middle of one resistance heating element. Thereby, a plurality of resistance heating elements were substantially realized. In another viewpoint, the feed portions (D1 to D3) are shared among the plurality of resistance heating elements. However, the resistance heating element may have the feeding parts (Pa and Pb) only at both ends. In other words, substantially only one resistance heating element may be provided. Also, the plurality of resistance heating elements may be separated from one another. In another aspect, the plurality of resistive heating elements may not share the power feeding unit with each other.

  Since a plurality of resistance heating elements that do not share the feeding part are not connected to each other, it is not possible to flow a common current (main current) as in the embodiment. Therefore, the plurality of resistance heating elements are supplied with power independently of each other. In addition, even when a plurality of resistance heating elements are connected to each other as in the embodiment, power may be supplied to the plurality of resistance heating elements independently of each other without flowing the main current.

  The wiring pattern (the wiring 4, the plurality of wirings 304a) may not be provided. The configuration of FIG. 10 (a) may be employed in all the feed units. In another aspect, the plurality of terminals may be dispersed at various positions. Also, for example, the wiring pattern may connect the power supply unit on the center side and the terminal on the outer peripheral side, contrary to the embodiment. In another aspect, the plurality of terminals may be aggregated on the outer peripheral side.

  The wiring pattern may not be parallel to the resistance heating element. The heater having such a configuration can be manufactured, for example, by producing a sintered body (base 1) by a hot press method and embedding a wire to be a wiring pattern at that time.

DESCRIPTION OF SYMBOLS 1 ... base | substrate, 2 ... resistance heating body, 3a ... connection conductor, 5 ... terminal, 10 ... heater, 10c ... upper surface (predetermined surface).

Claims (11)

An insulating substrate having a predetermined surface;
A resistive heating element extending along the predetermined surface on the predetermined surface or in the base;
A plurality of connection conductors each including a portion extending from the resistance heating element to a side opposite to the side facing the predetermined surface;
Terminals exposed to the side opposite to the side facing the predetermined surface of the base body, and the plurality of connection conductors are electrically connected in parallel with each other,
And have
A heater, wherein the plurality of connection conductors are arranged along a path of the resistance heating element in a direction in which the resistance heating element extends. A wire which is separated from the resistance heating element opposite to the side facing the predetermined surface, extends from the plurality of connection conductors along the predetermined surface, and is electrically connected to the terminal The heater according to claim 1, further comprising a pattern. The heater according to claim 1 or 2, wherein a sum of areas of cross sections orthogonal to the extending direction of the plurality of connection conductors is larger than an area of a cross section orthogonal to the extending direction of the resistance heating element. The area of the cross section orthogonal to the extending direction of the wiring pattern is larger than the sum of the areas of the cross sections orthogonal to the extending direction of the plurality of connection conductors. Heater as described. The diameter in the width direction of the resistance heating element of at least one of the plurality of connection conductors is at least 0.9 times and at most 1.1 times the width of the resistance heating element. The heater according to any one of the above. The substrate is made of ceramic,
The heater according to any one of claims 1 to 5, wherein at least one of the plurality of connection conductors is made of a pure metal or an alloy containing only a metal element. The heater according to claim 6, wherein the metal element of the pure metal or the metal element of the main component of the alloy is tungsten or molybdenum. The heater according to any one of claims 1 to 7, wherein at least one of the plurality of connection conductors penetrates the resistance heating element. The heater according to any one of claims 3 to 8, wherein at least any one of the plurality of connection conductors penetrates the wiring pattern, or directly or indirectly refers to claim 2 or claim 2. . The wiring pattern includes a plurality of wirings electrically connected to the terminals in parallel to one another and separately connected to the plurality of connection conductors. The heater according to any one of claims 3 to 9, which directly or indirectly refers to. The heater according to any one of claims 1 to 10,
A driving device for supplying power to the terminal;
Heater system that has.

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