Holding device

Abstract

To suppress deterioration in strength in connecting a terminal member to a terminal-side connection part.SOLUTION: A holding device according to the present disclosure comprises: a plate-like member that has a first surface that is nearly orthogonal to a first direction and a second surface at the opposite side of the first surface; an inner electrode arranged inside the plate-like member; a veer arranged to extend in the first direction inside the plate-like member and electrically connected to the inner electrode; a terminal member that can carry currents to the inner electrode; and a conductive connection member that electrically connects the veer to the terminal member. The connection member has a veer-side connection part 64 that is connected to the veer, and a terminal-side connection part that is connected to the terminal member. The veer-side connection part 64 and the terminal-side connection part are arranged at different positions in a direction orthogonal to the first direction.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a holding device for holding an object. [Background technology]

[0002] There is known a heating device (also called a "susceptor") that holds an object (e.g., a semiconductor wafer) and heats it to a predetermined temperature (e.g., about 400 to 800°C). The heating device is used as a part of semiconductor manufacturing equipment such as a film formation device (CVD film formation device, sputtering film formation device, etc.) or an etching device (plasma etching device, etc.).

[0003] In general, a heating device includes a ceramic member having a surface (hereinafter referred to as a "holding surface") substantially perpendicular to a predetermined direction and a surface (hereinafter referred to as a "rear surface") opposite to the holding surface. A resistance heating element such as tungsten (W) or molybdenum (Mo) is disposed inside the ceramic member. A conductive power receiving electrode, at least a portion of which is exposed on the rear surface of the ceramic member, is electrically connected to the resistance heating element. A metal electrode terminal unit is joined to the power receiving electrode by a joint formed of a metal brazing material. When a voltage is applied to the resistance heating element through the electrode terminal unit and the power receiving electrode, the resistance heating element generates heat, and an object held on the holding surface of the ceramic member is heated. For example, a heating device described in JP 2018-49964 A (Patent Document 1 below) is known as such a heating device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-49964 A Summary of the Invention [Problem to be solved by the invention]

[0005] The heating device includes a main substrate, a resistive heating element disposed inside the main substrate, and a power receiving electrode connected to an electrode terminal unit. In general, the resistive heating element is connected to the power receiving electrode through a via conductor. The main substrate is formed by stacking and sintering a plurality of green sheets, and the via conductor is formed by providing a through hole in each green sheet, filling the through hole with a metallization paste, and firing the green sheet. Since it is necessary to ensure contact between the via conductor and the power receiving electrode, the height of one via conductor is formed slightly thicker than the thickness of one green sheet. Therefore, the part of the power receiving electrode corresponding to the end of the via conductor protrudes, the flatness of the power receiving electrode is lost, and this is one of the factors that reduces the connection strength between the power receiving electrode and the terminal. In particular, when the resistive heating element and the power receiving electrode are connected through a plurality of via conductors, the end of the via conductor is pushed up against the power receiving electrode. [Means for solving the problem]

[0006] The holding device of the present disclosure comprises a plate-shaped member having a first surface substantially perpendicular to a first direction and a second surface opposite the first surface, an internal electrode arranged inside the plate-shaped member, a via arranged inside the plate-shaped member extending in the first direction and electrically connected to the internal electrode, a terminal member capable of conducting electricity to the internal electrode, and a conductive connecting member electrically connecting the via and the terminal member, wherein the connecting member has a via side connection portion connected to the via and a terminal side connection portion connected to the terminal member, and the via side connection portion and the terminal side connection portion are arranged at different positions in a direction perpendicular to the first direction. Effect of the Invention

[0007] According to the present disclosure, it is possible to suppress a decrease in the connection strength between the terminal member and the terminal-side connecting portion. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view that illustrates a heating device according to a first embodiment. [Diagram 2]FIG. 2 is a cross-sectional view showing the internal configuration of the heating device. [Diagram 3] FIG. 3 is an enlarged cross-sectional view of a portion of FIG. [Figure 4] FIG. 4 is an enlarged cross-sectional view of a portion of FIG. [Diagram 5] FIG. 5 is a cross-sectional view showing a state before a plurality of green sheets are thermocompression-bonded together. [Figure 6] FIG. 6 is a diagram showing how a metallization paste is printed on the lower surface of a green sheet to form a metallization conductor. [Figure 7] FIG. 7 is a diagram showing the arrangement of a plurality of metallized conductors formed on the lower surface of a green sheet. [Figure 8] FIG. 8 is a diagram showing the state after overcoating with ceramic paste so as to cover the metallization paste except for the connection surface with the electrode terminal. [Figure 9] FIG. 9 is a diagram showing a conventional structure and corresponds to FIG. [Figure 10] FIG. 10 is a diagram showing a conventional structure and corresponds to FIG. [Figure 11] FIG. 11 is a diagram illustrating the problems in the conventional structure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [Description of the embodiments of the present disclosure] First, the embodiments of the present disclosure will be listed and described. (1) A holding device of the present disclosure includes a plate-shaped member having a first surface substantially perpendicular to a first direction and a second surface opposite the first surface, an internal electrode arranged inside the plate-shaped member, a via arranged inside the plate-shaped member extending in the first direction and electrically connected to the internal electrode, a terminal member capable of conducting electricity to the internal electrode, and a conductive connecting member electrically connecting the via and the terminal member, wherein the connecting member has a via side connection portion connected to the via and a terminal side connection portion connected to the terminal member, and the via side connection portion and the terminal side connection portion are arranged at different positions in a direction perpendicular to the first direction.

[0010] Since the via side connection portion and the terminal side connection portion are arranged at different positions in a direction perpendicular to the first direction, even if the portion of the via side connection portion corresponding to the via is pushed up in the first direction, the terminal side connection portion is flat, so that a decrease in the connection strength between the terminal member and the terminal side connection portion can be suppressed.

[0011] (2) It is preferable that the connection member has a terminal side connection portion exposed on the second surface side of the plate-shaped member and a terminal side non-connection portion covered by an insulating member, and that the insulating member is disposed between the terminal side non-connection portion and the terminal member in the first direction. Since the terminal side non-connection portion is covered with an insulating member, the size of the exposed surface of the terminal side connection portion (connection member) can be adjusted, and the terminal side connection portion can be prevented from being exposed on the second surface side when connected to the terminal member.

[0012] (3) It is preferable that the connection members are provided in a plurality of numbers so as to be arranged circumferentially when viewed in the first direction, and the via-side connection portions are arranged on the outer periphery side of the terminal-side connection portions. Since the multiple via-side connecting portions can be arranged apart from each other, it is easy to arrange multiple vias.

[0013] (4) It is preferable that the connection member includes an aspect in which, when a connection region with the via is a first connection region and a connection region with the terminal member is a second connection region, a plurality of the first connection regions are connected to one second connection region. Since the number of current paths from the vias to the terminal members increases, the cross-sectional area of ​​the connection members can be increased to reduce conductor resistance, thereby suppressing heat generation.

[0014] [Details of the First Embodiment of the Present Disclosure] Specific examples of the retaining device of the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims.

[0015] <Heating device> The holding device of the present disclosure is a heating device 100 that holds an object (e.g., a semiconductor wafer W) and heats it to a predetermined processing temperature (e.g., 400 to 800°C), and is also called a susceptor. The heating device 100 is used as a part of a semiconductor manufacturing device such as a film forming device (CVD film forming device, sputtering film forming device, etc.) or an etching device (plasma etching device, etc.). As shown in FIG. 1, the heating device 100 includes a holder 10 and a columnar support 20. The heating device 100 corresponds to the "holding device" in the claims. The technology disclosed in this specification can be applied to electrostatic chucks, holding devices, etc. in addition to heating devices.

[0016] <Holding body> As shown in Fig. 2, the holder 10 is a substantially disk-shaped member having a holding surface S1 and a back surface S2 that are substantially perpendicular to the vertical direction. The holder 10 is formed of an insulating material such as ceramics whose main component is aluminum nitride (AlN) or alumina (Al2O3). The main component here means the component with the highest content (weight percentage). The diameter of the holder 10 is, for example, about 100 mm or more and 500 mm or less. The holder 10 corresponds to the "plate-shaped member" in the claims, the vertical direction corresponds to the "first direction" in the claims, the holding surface S1 corresponds to the "first surface" in the claims, and the back surface S2 corresponds to the "second surface" in the claims.

[0017] A resistive heating element 50 is embedded inside the holder 10 as a heater electrode for heating the holder 10. The resistive heating element 50 is made of a conductive material such as tungsten or molybdenum. When viewed from above, the resistive heating element 50 forms a linear pattern extending approximately concentrically. Both ends of the linear pattern of the resistive heating element 50 are connected to the upper ends of first vias 52A via via pads. The resistive heating element 50 corresponds to the "internal electrode" in the claims.

[0018] The lower end of the first via 52A is connected to the first land 55A. A via pad 58 is provided below the first land 55A. The first land 55A and the via pad 58 are connected via the second via 52B. A conductive metallized conductor 60 is provided below the via pad 58. The metallized conductor 60 corresponds to the "connecting member" in the claims. The metallized conductor 60 is disposed near the center of the holder 10. The via pad 58 and the metallized conductor 60 are connected via the third via 52C. The portion of the metallized conductor 60 connected to the third via 52C is defined as a via side connection portion 64.

[0019] A pair of terminal holes 12 are formed on the rear surface S2 side of the holding body 10. A terminal side electrode 62 is provided at the upper end of each terminal hole 12. The terminal side electrode 62 includes a portion (an inner portion IP described below) of the metallized conductor 60 exposed on the rear surface S2 side of the holding body 10. The resistance heating element 50 and the metallized conductor 60 are electrically connected via each of the vias 52A, 52B, 52C, etc.

[0020] <Columnar support> The columnar support 20 is a substantially cylindrical member extending in the vertical direction. Like the holder 10, the columnar support 20 is formed of an insulating member such as ceramics mainly composed of aluminum nitride or alumina. The outer diameter of the columnar support 20 is, for example, about 30 mm or more and 90 mm or less, and the height of the columnar support 20 (length in the vertical direction) is, for example, about 100 mm or more and 300 mm or less.

[0021] The holder 10 and the columnar support 20 are arranged so that the back surface S2 of the holder 10 and the top surface S5 of the columnar support 20 face each other in the vertical direction. The columnar support 20 is joined to the vicinity of the center of the back surface S2 of the holder 10 via a joint 30 formed from a known joining material.

[0022] As shown in Fig. 2, the columnar support 20 has a through hole 22 that opens to the rear surface S2 side of the holder 10. The through hole 22 is a hole that extends in the vertical direction and has a substantially constant inner diameter along the extension direction and has a substantially circular cross section. A plurality of electrode terminals 74 are housed in the through hole 22. The electrode terminals 74 are substantially circular columnar members when viewed from above, and are made of a conductive material such as nickel (Ni). The diameter of the electrode terminals 74 is, for example, about 2 mm or more and 6 mm or less.

[0023] A pellet 72 is disposed between the upper end of the electrode terminal 74 and the metallized conductor 60 in the vertical direction. The pellet 72 is a substantially circular plate-like member when viewed from above, and is made of a metal such as tungsten, molybdenum, or kovar. However, since the pellet 72 has a function of reducing the thermal expansion difference between the electrode terminal 74 and the metallized conductor 60, it is preferable that a material having a thermal expansion coefficient between the thermal expansion coefficient of the electrode terminal 74 and the thermal expansion coefficient of the metallized conductor 60 is used as a material for forming the pellet 72. The diameter of the pellet 72 is, for example, about 3 mm or more and 9 mm or less, and the thickness of the pellet 72 is, for example, about 1 mm or more and 6 mm or less. The pellet 72 and the electrode terminal 74 correspond to the "terminal member" in the claims.

[0024] As shown in FIG. 3 and FIG. 4, the pellet 72 is joined (brazed) to the inside part IP of the terminal side electrode 62 by the first joint part 76 formed by the inactive brazing material. The inactive brazing material means a brazing material that does not substantially chemically bond to ceramics, for example, Ni-based (Ni-Cr-based alloy, etc.), Au-based (pure Au, Au-Ni-based alloy, etc.), Ag-based (pure Ag, etc.) brazing material. Since the heating device 100 is used in an atmospheric environment of about 400 to 800°C, if the brazing material contains a component that is easily oxidized, such as Cu, there is a concern that the brazing material may deteriorate. Therefore, it is preferable that the brazing material does not contain a component that is easily oxidized, such as Cu. In this embodiment, the first joint part 76 is formed so as to face not only the lower surface of the inside part IP of the terminal side electrode 62, but also the back surface S2 of the holder 10. However, since the first joint part 76 is formed by the inactive brazing material, it is not joined to the holder 10.

[0025] On the other hand, the pellet 72 is joined to the electrode terminal 74 by a second joint portion 78 formed of a brazing material. The second joint portion 78 is, for example, an Ag-based brazing material. The first joint portion 76 and the second joint portion 78 correspond to the "terminal member" in the claims.

[0026] When a voltage is applied from a power source not shown to the resistive heating element 50 via the electrode terminal 74, the second joint 78, the pellet 72, the first joint 76, the metallized conductor 60, each of the vias 52A, 52B, 52C, each of the via pads, and each of the lands 55A, 55B, the resistive heating element 50 generates heat, and the object (e.g., a semiconductor wafer W) held on the holding surface S1 of the holder 10 is heated to a predetermined temperature (e.g., about 400 to 800°C).

[0027] <Detailed configuration of metallized conductor> The configuration of the metallized conductor 60 will be described in more detail. The metallized conductor 60 of this embodiment is formed to include a metal material and a ceramic material. The metal material included in the metallized conductor 60 is, for example, tungsten or molybdenum. The metal material included in the metallized conductor 60 is preferably a metal material having a thermal expansion coefficient close to that of the metal material constituting the pellet 72. The ceramic material included in the metallized conductor 60 is, for example, aluminum nitride or alumina. The ceramic material included in the metallized conductor 60 is preferably a ceramic material having a thermal expansion coefficient close to that of the ceramic material that is the main component of the holder 10.

[0028] Moreover, the terminal side electrode 62 of the metallized conductor 60 is, for example, a substantially circular, flat member when viewed from above. However, the terminal side electrode 62 has a shape in which the outer periphery is bent obliquely upward over the entire circumference. That is, the terminal side electrode 62 is composed of an outer periphery portion OP that is bent in this way and located inside the holder 10, and an inner portion IP that is a substantially flat plate-like portion other than the outer periphery portion OP. The outer periphery portion OP corresponds to the "terminal side non-connected portion" in the claims, and the inner portion IP corresponds to the "terminal side connected portion" in the claims.

[0029] The area corresponding to the inner and outer periphery parts OP of the surface (lower surface) S3 of the terminal side electrode 62 facing the first joint part 76 is covered with an insulating member 13 such as a ceramic material constituting the holding body 10, while the area corresponding to the inner part IP is exposed on the back surface S2 side of the holding body 10. The diameter of the inner part IP of the terminal side electrode 62 is, for example, about 3 mm or more and 12 mm or less, and the thickness of the terminal side electrode 62 is, for example, about 0.005 mm or more and 0.15 mm or less. The maximum thickness (maximum covering thickness) of the insulating member 13 covering the outer periphery part OP is, for example, about 0.005 mm or more and 0.1 mm or less. The material of the insulating member 13 is the same as that of the holding body 10. Since the insulating member 13 is made of the same material as the holding body 10, the insulating member 13 and the holding body 10 can be formed integrally. Furthermore, since the outer periphery portion OP is covered with the insulating member 13, when the inner portions IP are arranged circumferentially in a plan view, the opposing inner portions IP can be arranged close to each other.

[0030] The terminal side electrode 62 and the via side connection portion 64 are provided at different positions in the horizontal direction (direction perpendicular to the up-down direction). The terminal side electrode 62 is connected to the via side connection portion 64 via the relay connection portion 69. The via side connection portion 64, the relay connection portion 69, and the terminal side electrode 62 are arranged at approximately the same height in the up-down direction and are arranged side by side in the horizontal direction. The via side connection portion 64 and the terminal side electrode 62 are arranged at a distance of the horizontal length of the relay connection portion 69. In other words, the third via 52C does not overlap with the electrode terminal 74 and the second joint portion 78 in a plan view (top view), and when there are multiple third vias 52C, all the third vias 52C, the electrode terminal 74, and the second joint portion 78 are arranged not to overlap with each other in a plan view.

[0031] <Method of manufacturing the heating device> The manufacturing method of the heating device 100 of this embodiment is, for example, as follows: First, the holder 10 and the columnar supports 20 are produced.

[0032] The method for producing the holder 10 is, for example, as follows. First, an organic solvent such as toluene is added to a mixture of 100 parts by weight of aluminum nitride powder, 1 part by weight of yttrium oxide (Y2O3) powder, 20 parts by weight of an acrylic binder, and an appropriate amount of dispersant and plasticizer, and the mixture is mixed in a ball mill for 20 hours to produce a slurry for the green sheet. This slurry for the green sheet is formed into a sheet shape using a casting device and then dried to produce multiple green sheets 65.

[0033] Metal powder such as tungsten or molybdenum is added to and kneaded with a mixture of aluminum nitride powder, an acrylic binder, and an organic solvent such as terpineol to prepare a metallization paste 66. By printing this metallization paste 66 using, for example, a screen printing device, unsintered conductor layers that will later become the resistance heating element 50, the first lands 55A, the via pads 58, and the metallization conductors 60 are formed on each specific green sheet 65 as shown in FIG.

[0034] As shown in Fig. 6, the metallized conductor 60 is formed into a horizontally long elliptical shape by printing a metallized paste 66 over a first connection region 53 which is a connection region with the plurality of third vias 52C and a second connection region 54 which is a connection region with an electrode terminal 74 arranged in a terminal hole 12 of the holder 10. To explain in more detail with reference to Fig. 7, for example, five second connection regions 54 are provided so as to be arranged on a circumference in a plan view, and the first connection regions 53 are arranged on the outer periphery of these second connection regions 54. One first connection region 53 is connected to one second connection region 54, but two first connection regions 53 may be connected to one second connection region 54.

[0035] When the third via 52C and the terminal side electrode 62 are arranged with a shift as in the present disclosure, there is a possibility that the metallized conductor 60 will generate heat. As a countermeasure to this, for example, it is conceivable to increase the thickness of the metallized conductor 60 to increase its cross-sectional area. However, if the thickness of the metallized conductor 60 is increased, a gap will be generated between the metallized paste 66 and the green sheet 65 during manufacturing, which will result in a gap being generated between the metallized conductor 60 and the ceramic member forming the holder 10, which may cause cracks, or the thickness of the holder 10 will become thicker, making this an undesirable measure.

[0036] Therefore, if two first connection regions 53 are connected to one second connection region 54 of the metallized conductor 60, the number of current paths from the third via 52C to the terminal electrode 62 will double, and the amount of current passing through one path can be reduced, suppressing heat generation. Here, the technical significance of doubling the number of paths will be considered. Simply doubling the number of paths means doubling the cross-sectional area, so even if one path is made thicker and wider to double its cross-sectional area, the cross-sectional area is the same, so the resistance value will be the same and it seems that heat generation can be suppressed. However, it has been found from the results of simulations that the current does not flow evenly within the path, but tends to concentrate in the path with the shortest distance. Therefore, it is considered that the resistance value will be reduced and the effect of increasing the number of paths (the effect of suppressing heat generation) will be more easily obtained by doubling the number of paths and allowing current to flow through each path to increase the total amount of current, rather than by making one path thicker and wider.

[0037] 7 illustrates an example in which two first connection regions 53 are connected to the second connection region 54, but three or more first connection regions 53 may be connected to the second connection region 54. Also, in FIG. 7, an example is shown in which a single L-shaped metallized conductor 60 connects two first connection regions 53 and the second connection region 54, but it may be separated into two I-shaped metallized conductors 60.

[0038] When printing the metallization paste 66, for example, the metallization paste 66 is printed in one go to a thickness of 50 μm or more, and then dried to volatilize the organic solvent. This process is repeated until the set thickness is reached. Next, as shown in FIG. 8, after printing each metallization paste 66 for the metallized conductor 60, the metallization paste 66 is overcoated with a ceramic paste (for example, a mixture of aluminum nitride, an acrylic binder, and an organic solvent such as terpineol) 68 so as to cover the entire outer periphery 67 of the metallization paste 66.

[0039] Next, as shown in Fig. 5, these green sheets 65 are stacked, and then a plurality of sheets (e.g., 20 sheets) are thermocompression bonded, and the outer periphery is cut as necessary to produce a green sheet laminate (e.g., 8 mm thick). This green sheet laminate is cut by machining to produce a disk-shaped compact, which is degreased, and the degreased body is fired to produce a fired body, and the surface of the fired body is polished. Through the above steps, the holder 10 is produced.

[0040] The columnar support 20 is produced, for example, as follows. First, an organic solvent such as methanol is added to a mixture of 100 parts by weight of aluminum nitride powder, 1 part by weight of yttrium oxide powder, 3 parts by weight of PVA binder, and an appropriate amount of dispersant and plasticizer, and mixed in a ball mill to obtain a slurry. This slurry is granulated in a spray dryer to produce a raw material powder. Next, the raw material powder is filled into a rubber mold in which a core corresponding to the through hole 22 is placed, and a molded body is obtained by cold isostatic pressing. The obtained molded body is degreased, and the degreased body is further fired. Through the above steps, the columnar support 20 is produced.

[0041] Next, the support 10 and the columnar supports 20 are bonded together. After performing lapping on the back surface S2 of the support 10 and the top surface S5 of the columnar supports 20 as necessary, a known bonding agent made into a paste form by mixing, for example, rare earth elements and an organic solvent is uniformly applied to at least one of the back surface S2 of the support 10 and the top surface S5 of the columnar supports 20, and then a degreasing process is performed. Next, the back surface S2 of the support 10 and the top surface S5 of the columnar supports 20 are overlapped and heated to bond the support 10 and the columnar supports 20 together.

[0042] After the holder 10 and the columnar support 20 are joined, each pellet 72 is inserted into the through hole 22, and the upper end of each pellet 72 is brazed (950 to 1150°C, 10 to 30 minutes) to the lower surface S3 of each terminal side electrode 62 using a non-active brazing material (e.g., Ni-based, Au-based, or Ag-based brazing material), thereby forming a first joint 76. Furthermore, each electrode terminal 74 is inserted into the through hole 22, and the upper end of each electrode terminal 74 is brazed to each pellet 72 using, for example, an Ag-based brazing material, thereby forming a second joint 78. The heating device 100 having the above-mentioned configuration is manufactured mainly by the above manufacturing method.

[0043] <Conventional structure and its problems> Before describing the effects of this embodiment, a conventional structure and its problems will be described. As shown in Figures 9 and 10, conventionally, metallization paste 66 was printed directly on the lower end of via conductor 51. This has the advantage of being advantageous in preventing heat generation in metallization conductor 61 because the distance from via conductor 51 to electrode terminal 74 is shortened and the conductor resistance is reduced.

[0044] However, the via conductors 51 are formed by providing through holes in each green sheet, filling the through holes with metallization paste, and firing the green sheet. The height of each via conductor 51 is formed slightly thicker than the thickness of one green sheet. Therefore, when multiple via conductors 51 are stacked, as shown in FIG. 11(A), a part of the via conductor 51 may protrude into the inside of the terminal hole 11, forming unevenness. In such a case, when the metallization paste 66 is printed in the via connection region 53, the metallization paste 66 is printed along the unevenness, and therefore the phenomenon that the metallization conductor 61 is also formed uneven (hereinafter referred to as "via push-up") may occur. Therefore, as shown in FIG. 11(B), when the brazing material 71 is applied to the metallization conductor 61, the lower surface of the brazing material 71 is formed unevenly, and a gap is formed between the lower surface of the brazing material 71 and the upper surface of the electrode terminal 74. As a result, the connection strength between the metallization conductor 61 and the electrode terminal 74 is reduced.

[0045] 11(C), it is conceivable to fill the gap between the metallized conductor 61 and the brazing material 71 by thickening the brazing material 71. In this way, it is possible to eliminate the gap between the metallized conductor 61 and the brazing material 71 and the gap between the brazing material 71 and the electrode terminal 74. However, as the brazing material 71 becomes thicker, the stress caused by the difference in thermal expansion increases, and the load on the joint increases. Furthermore, the adhesion between the metallized conductor 61 and the aluminum nitride (holding body 10) is weak, and the stress from the brazing material 71 makes it easy for the metallized conductor 61 to peel off (crack) from its end.

[0046] In addition, in order to eliminate the gap between the brazing material 71 and the electrode terminal 74, if the brazing material 71 is applied in advance to the upper surface of the electrode terminal 74 as shown in Figure 11 (D), the upper surface of the brazing material 71 becomes flat, making it easier for a gap to occur between the metallized conductor 61 and the brazing material 71.

[0047] In this way, in the conventional structure, since the metallization paste 66 was directly printed on the ends of the via conductors 51, unevenness was generated due to the vias being pushed up, and it was difficult to eliminate the gaps caused by the unevenness. Conversely, if the brazing material 71 was made thicker to avoid such problems, there was a problem that peeling from the ends of the metallized conductors 61 would be more likely to occur.

[0048] Furthermore, during firing, AlN precipitates made of aluminum nitride are generated on the surface of the metallized conductor 61, and many AlN precipitates are generated particularly at positions corresponding to the ends of the via conductors 51 (hereinafter referred to as "via precipitates"). Since the AlN precipitates are an insulator, there is a problem in that the contact area with the electrode terminal 74 becomes small.

[0049] <Effects of this embodiment> The heating device 100 of the present disclosure includes a holder 10 having a holding surface S1 that is approximately perpendicular to the vertical direction and a back surface S2 opposite to the holding surface S1, a resistance heating element 50 arranged inside the holder 10, vias 52A, 52B, 52C that are arranged extending in the vertical direction inside the holder 10 and are electrically connected to the resistance heating element 50, a pellet 72 and an electrode terminal 74 that can pass electricity through the resistance heating element 50, and a conductive metallized conductor 60 that electrically connects the vias 52A, 52B, 52C to the pellet 72 and the electrode terminal 74, wherein the metallized conductor 60 has a via side connection portion 64 connected to the vias 52A, 52B, 52C and an inner portion IP of the terminal side electrode 62 connected to the pellet 72 and the electrode terminal 74, and the via side connection portion 64 and the inner portion IP of the terminal side electrode 62 are arranged at different positions in a direction perpendicular to the vertical direction.

[0050] Since the via side connection portion 64 and the inner portion IP of the terminal side electrode 62 are positioned at different positions in a direction perpendicular to the vertical direction, even if the portions of the via side connection portion 64 corresponding to the vias 52A, 52B, and 52C are pushed up in the vertical direction, i.e., via push-up occurs, the inner portion IP of the terminal side electrode 62 is flat, so that a decrease in the connection strength between the pellet 72 and the electrode terminal 74 and the inner portion IP of the terminal side electrode 62 can be suppressed.

[0051] Furthermore, even if AlN precipitates remain in the portions of the via-side connection portion 64 corresponding to the vias 52A, 52B, and 52C, that is, via precipitation occurs, this does not pose a problem because the AlN precipitates and the green sheet are made of the same material.

[0052] The metallized conductor 60 has an inner portion IP exposed on the back surface S2 side of the holder 10, and an outer peripheral portion OP covered by an insulating member 13, and it is preferable that the insulating member 13 is arranged between the outer peripheral portion OP and the pellet 72 and the electrode terminal 74 in the vertical direction.

[0053] If the metallized conductor 60 is heated to a high temperature while exposed on the rear surface S2 side, the tungsten in the metallized conductor 60 will oxidize. Therefore, in the above configuration, the outer periphery OP is overcoated with the insulating member 13 to cover it, so that the size of the exposed surface of the inner portion IP (metallized conductor 60) can be adjusted and the inner portion IP can be prevented from being exposed on the rear surface S2 side when connected to the pellet 72 and the electrode terminal 74. Therefore, oxidation of the tungsten in the metallized conductor 60 can be suppressed. In addition, the overcoat with the insulating member 13 can prevent peeling from the end of the metallized conductor 60.

[0054] It is preferable that the metallized conductor 60 includes an embodiment in which, when the connection region with the third via 52C is defined as the first connection region 53 and the connection region with the electrode terminal 74 is defined as the second connection region 54, two first connection regions 53 are connected to one second connection region 54. Since the current path from the third via 52C to the electrode terminal 74 is doubled, the cross-sectional area of ​​the metallized conductor 60 can be increased to reduce the conductor resistance, thereby suppressing heat generation.

[0055] <Other embodiments> (1) In the above embodiment, the pellet 72 is disposed between the electrode terminal 74 and the terminal electrode 62, but the electrode terminal 74 and the terminal electrode 62 may be joined by a joint formed of a brazing material without disposing the pellet 72. In such a configuration, the brazing material and the electrode terminal 74 correspond to the "terminal member" in the claims.

[0056] (2) In the above embodiment, the terminal side electrode 62 has a shape in which the outer peripheral portion of a substantially flat plate-like member is bent diagonally upward around the entire circumference, but the terminal side electrode may have other shapes as long as the outer peripheral portion is positioned inside the holder 10 and the inner portion is exposed to the terminal hole 12.

[0057] (3) In the above embodiment, the configuration of the terminal side electrode 62 electrically connected to the resistive heating element 50 arranged inside the holder 10 was described. However, the terminal side electrode electrically connected to other internal electrodes arranged inside the holder 10 may have a similar configuration.

[0058] (4) The materials used to form the components of the heating device in the above embodiment are merely examples, and the components may be formed of other materials. Furthermore, the manufacturing method of the heating device in the above embodiment is merely an example, and various modifications are possible.

[0059] (5) Furthermore, the present disclosure is not limited to the heating device 100, but is similarly applicable to other holding devices (e.g., electrostatic chucks, etc.) that include a ceramic member, an internal electrode (heater electrode, chuck electrode, RF electrode, etc.) disposed inside the ceramic member, a via electrically connected to the internal electrode, a terminal member capable of passing electricity through the internal electrode, and a conductive connecting member electrically connecting the via and the terminal member, and that hold an object on the surface of the ceramic member.

[0060] (6) In the above embodiment, the outer periphery OP of the terminal electrode 62 is covered with the insulating member 13. However, the outer periphery OP may be exposed to the inside of the terminal hole 12.

[0061] (7) In the above embodiment, the via side connection portion 64 is arranged on the outer periphery of the inner portion IP of the terminal side electrode 62, but both the via side connection portion and the inner portion of the terminal side electrode may be arranged on the circumference in a planar view. [Explanation of symbols]

[0062] 10...Holding body (plate-shaped member) 11...Terminal hole 12...Terminal hole 13...Insulating member 20...Column support 22...Through hole 30…Joint part 50... Resistance heating element (internal electrode) 51... Via conductor 52A... First via 52B... Second via 52C... Third via 53... First connection area 54... Second connection area 55A... First land 55B... Second land 56... Via 57... Via 58... Via pad 60... Metallized conductor (connecting member) 61... Metallized conductor 62... Terminal side electrode 64... Via side connection portion 65... Green sheet 66... ​​Metallized paste 67... Outer periphery 68... Ceramic paste 69... Relay connection portion 71: brazing material; 72: pellet (terminal member); 74: electrode terminal (terminal member); 76: first joint portion; 78: second joint portion 100...Heating device (holding device) CD: Current flow direction IP: Inner part (terminal side connection part) OP: Outer part (terminal side non-connection part) S1: Holding surface (first surface) S2: Back surface (second surface) S3: Bottom surface S5: Top surface W…Semiconductor wafer (object)

Claims

1. a plate-like member having a first surface substantially perpendicular to a first direction and a second surface opposite to the first surface; an internal electrode disposed inside the plate-shaped member; a via disposed inside the plate-like member and extending in the first direction and electrically connected to the internal electrode; a terminal member capable of conducting current to the internal electrode; a conductive connection member that electrically connects the via and the terminal member, the connection member has a via-side connection portion connected to the via, and a terminal-side connection portion connected to the terminal member, the terminal member and the terminal-side connection portion being connected to each other without any vias; the via-side connection portion and the terminal-side connection portion are disposed at different positions in a direction perpendicular to the first direction, when a connection region of the connection member to the via is defined as a first connection region and a connection region of the connection member to the terminal member is defined as a second connection region, a plurality of the second connection regions are provided so as to be arranged circumferentially when viewed in the first direction, A holding device, wherein the first connection region is disposed on an outer circumferential side relative to the second connection region.

2. 2. The holding device according to claim 1, wherein the connecting member has a terminal side connection portion exposed on the second surface side of the plate-shaped member and a terminal side non-connection portion covered by an insulating member, and the insulating member is disposed between the terminal side non-connection portion and the terminal member in the first direction.

3. The holding device according to claim 1 or 2, wherein the connection member includes an aspect in which a plurality of the first connection regions are connected to one of the second connection regions.

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