Electrical circuit connection, conductive sheet, electrostatic chuck, and heater

Abstract

The present invention provides an electrical circuit connection that favorably connects an electrode circuit and a connection circuit and has excellent durability (long life, electrical characteristics (conductivity, insulating properties) and the like), a conductive sheet, an electrostatic chuck, and a heater. This electrical circuit connection (31) connects an electrode circuit (10) and a connection circuit (20). The electrode circuit (10) includes an electrode conductor (11) that comprises a first conductive material (12), the connection circuit (20) includes a connection conductor (21) that comprises a second conductive material (22), and, between the electrode conductor (11) and the connection conductor (21), the electrical circuit connection (31) includes a mixture region (21) that comprises the materials included in the first conductive material (12) and the second conductive material (22) and mixes and joins the first conductive material (12) and the second conductive material (22).

Description

Electrical circuit connection part, conductive sheet, electrostatic chuck, and heater

[0001] The present invention relates to an electrical circuit connection part, a conductive sheet, an electrostatic chuck, and a heater.

[0002] When performing processes such as substrate processing and film deposition on substrates using semiconductor wafers, glass substrates, insulating substrates, etc., an electrostatic chuck is used to hold the substrate in a predetermined position (see, for example, Patent Documents 1 to 3).

[0003] Japanese Patent Publication No. 7392887 Japanese Patent Publication No. 7392888 Japanese Unexamined Patent Publication No. 2021-197529

[0004] When connecting a power supply circuit to electrode circuits such as electrostatic chucks and heaters, it is desirable to have a method that allows for stable connection between these circuits and facilitates handling of the circuits after connection.

[0005] The present invention has been made in view of the above circumstances, and aims to provide an electrical circuit connection part, a conductive sheet, an electrostatic chuck, and a heater that can connect electrode circuits and connection circuits well and have excellent durability (long lifespan, electrical characteristics (conductivity, insulation), etc.).

[0006] The present invention includes the following embodiments.

[0007] [1] An electrical circuit connection part for connecting an electrode circuit and a connecting circuit, wherein the electrode circuit has an electrode conductor made of a first conductive material, the connecting circuit has a connecting conductor made of a second conductive material, and the electrical circuit connection part has a mixed region between the electrode conductor and the connecting conductor, the first conductive material and the second conductive material being mixed and joined together. [2] The electrical circuit connection part according to [1], wherein in the mixed region, a metal contained in the first conductive material and a metal contained in the second conductive material are mixed together. [3] The electrical circuit connection part according to [1] or [2], wherein the first conductive material contains a metal with a lower electrical resistivity than the metal contained in the second conductive material. [4] The electrical circuit connection part according to any one of [1] to [3], wherein the first conductive material contains a metal with a higher electrical resistivity than the metal contained in the second conductive material. [5] An electrical circuit connection according to any one of [1] to [4], characterized in that a plurality of mixed regions are formed between the electrode conductor and the connecting conductor, and non-jointed portions are interposed between these plurality of mixed regions where the electrode conductor and the connecting conductor are not joined. [6] An electrical circuit connection according to any one of [1] to [5], characterized in that the mixed regions are formed by welding the first conductive material and the second conductive material. [7] An electrical circuit connection according to any one of [1] to [6], characterized in that the electrode conductor is an electrode sheet made of the first conductive material, the connecting conductor is a connecting sheet made of the second conductive material, and the mixed regions are formed between one side in the thickness direction of the electrode sheet and one side in the thickness direction of the connecting sheet. [8] In a field of view perpendicular to the electrode sheet, the area of ​​each of the mixed regions is 0.0001 mm². ２ 0.5 mm or more ２The electrical circuit connection part according to [7], characterized in that it is within the following range and the shortest distance between adjacent mixed regions is within the range of 0.05 mm to 5.0 mm. [9] The electrical circuit connection part according to [7] or [8], characterized in that the electrode sheet has irregularities around the region to be joined with the connection sheet.

[10] The electrical circuit connection part according to any one of [7] to [9], characterized in that the electrode circuit includes an insulating resin film laminated on the electrode sheet.

[0008]

[11] A conductive sheet comprising a sheet-shaped electrode circuit and a sheet-shaped connection circuit, wherein an electrical circuit connection portion according to any one of [1] to

[10] is provided between the electrode circuit and the connection circuit.

[12] The conductive sheet according to

[11] , wherein at least one of the electrode circuit or the connection circuit includes an insulating resin layer.

[13] The conductive sheet according to

[11] or

[12] , wherein at least one of the electrode circuit or the connection circuit includes an insulating resin film.

[14] An electrostatic chuck comprising an electrode circuit and a connection circuit, wherein an electrical circuit connection portion according to any one of [1] to

[10] is provided between the electrode circuit and the connection circuit.

[15] A heater comprising an electrode circuit and a connection circuit, wherein an electrical circuit connection portion according to any one of [1] to

[10] is provided between the electrode circuit and the connection circuit.

[0009] According to the present invention, it is possible to provide an electrical circuit connection part, a conductive sheet, an electrostatic chuck, and a heater that can connect electrode circuits and connection circuits well and have excellent durability (long lifespan, electrical characteristics (conductivity, insulation), etc.).

[0010] This is a cross-sectional view illustrating an electrical circuit connection portion of an embodiment. This is a cross-sectional view illustrating a conductive sheet of an embodiment. This is a cross-sectional view illustrating an electrostatic chuck or heater of an embodiment. This is a side view showing a first example of an electrical circuit connection portion between an electrode sheet and a connecting sheet. This is a side view showing a second example of an electrical circuit connection portion between an electrode sheet and a connecting sheet. This is a side view showing a third example of an electrical circuit connection portion between an electrode sheet and a connecting sheet. This is a side view showing a fourth example of an electrical circuit connection portion between an electrode sheet and a connecting sheet.

[0011] The present invention will be described below based on preferred embodiments. Note that the dimensional ratios of the components in the drawings may not necessarily be the same as those in reality.

[0012] <Electrical Circuit Connection and Conductive Sheet> Figure 1 is a schematic cross-sectional view illustrating the electrical circuit connection of the embodiment. Figure 2 is a schematic cross-sectional view illustrating the conductive sheet of the embodiment.

[0013] The illustrated example shows an electrical circuit connection part 31 and a conductive sheet 30 that connect the electrode circuit 10 and the connection circuit 20. The electrode circuit 10 has an electrode conductor 11 made of a first conductive material 12. The connection circuit 20 has a connection conductor 21 made of a second conductive material 22.

[0014] The electrical circuit connection portion 31 has a mixed region 32 between the electrode conductor 11 and the connecting conductor 21. The mixed region 32 consists of materials contained in the first conductive material 12 and the second conductive material 22, with the first conductive material 12 and the second conductive material 22 being mixed together. The electrode conductor 11 and the connecting conductor 21 are joined together via this mixed region 32. By mixing the conductive materials in the mixed region 32, an electrical circuit connection portion 31 with excellent durability (long lifespan, electrical properties (conductivity, insulation), etc.) can be obtained.

[0015] The first conductive material 12 is not particularly limited, but examples include metals and carbon. The metal may be an element or an alloy. The conductive material contained in the first conductive material 12 may be one type or two or more types. The first conductive material 12 may contain conductive materials of the same type as those contained in the second conductive material 22, or it may contain conductive materials different from those contained in the second conductive material 22. The first conductive material 12 may be mainly metal, may be a conductive material other than metal, or may be a material in which metal and non-metal conductive materials are mixed.

[0016] The second conductive material 22 is not particularly limited, but examples include metals and carbon. The metal may be an element or an alloy. The conductive material contained in the second conductive material 22 may be one type or two or more types. The second conductive material 22 may contain the same type of conductive material as the conductive material contained in the first conductive material 12, or it may contain a different conductive material than the first conductive material 12. The second conductive material 22 may be mainly a metal, may be a conductive material other than a metal, or may be a mixture of a metal and a non-metal conductive material.

[0017] Specific examples of conductive materials used in the first conductive material 12 and / or the second conductive material 22 include iron (Fe), chromium (Cr), nickel (Ni), tungsten (W), molybdenum (Mo), stainless steel (SUS), aluminum (Al), zinc (Zn), titanium (Ti), tin (Sn), gold (Au), silver (Ag), copper (Cu), and platinum (Pt). Examples of carbon include graphite.

[0018] The first conductive material 12 is preferably selected from an appropriate material depending on the function of the electrode circuit 10, which includes the electrode conductor 11. For example, the electrode conductor 11 may be made of a high-melting-point metal. If the electrode is for a heater, it may be made of a conductive material with high resistivity. The pattern and shape of the electrode are not particularly limited and can be appropriately designed depending on the function of the electrode.

[0019] The second conductive material 22 is preferably selected from an appropriate material depending on the function of the connection circuit 20 which includes the connecting conductor 21. For example, if the connection circuit 20 is arranged with the connecting conductor 21 bent, it is preferable to use a connecting conductor 21 that has bending resistance. This makes it easier to distribute the force acting on the electrical circuit connection part 31 and the conductive sheet 30. As a result, the electrical circuit connection part 31 and the conductive sheet 30 with superior durability can be obtained.

[0020] The resistivity of the electrode conductor 11 made of the first conductive material 12 may be greater than, less than, or equal to the resistivity of the connection conductor 21 made of the second conductive material 22. For example, when the electrode conductor 11 has a heater function, the resistivity of the electrode conductor 11 is less than the resistivity of the connection conductor 21.

[0021] In the mixed region 32 used for joining the electrode conductor 11 made of the first conductive material 12 and the connection conductor 21 made of the second conductive material 22, the first conductive material 12 and the second conductive material 22 are mixed. The electrode conductor 11 and the connection conductor 21 may be joined in this mixed region 32 without any material other than the first conductive material 12 and the second conductive material 22 intervening. For example, the base materials (the first conductive material 12 and the second conductive material 22) may be joined without supplying solder, welding filler, conductive paste, flux, etc.

[0022] Here, the cross-sectional areas of the first conductive material 12 and the second conductive material 22 in the mixed region 32 and the cross-sectional area of the mixed region 32 can be calculated, for example, based on the observation results of the cross-section of the mixed region 32 by X-ray spectroscopy or the like. Examples of the X-ray spectroscopy used for cross-section observation include energy dispersive X-ray spectroscopy (SEM-EDX) using a scanning electron microscope, energy dispersive X-ray spectroscopy (TEM-EDX) using a transmission electron microscope, X-ray photoelectron spectroscopy (XPS), etc., but the cross-section observation method is not limited to these.

[0023] The electrode conductor 11 includes the first conductive material 12 in a region other than the mixed region 32. The electrode conductor 11 in a region other than the mixed region 32 may be a conductive material in which no material other than the first conductive material 12 intervenes. For example, in the electrode sheet 15 protected by the insulating resin layer 16, the electrode conductor 11 may be composed of the first conductive material 12.

[0024] The connection conductor 21 contains the second conductive material 22 in a region other than the mixed region 32. The connection conductor 21 in a region other than the mixed region 32 may be a conductive material in which no material other than the second conductive material 22 intervenes. For example, in the connection sheet 25 protected by the insulating resin layer 26, the connection conductor 21 may be composed of the second conductive material 22.

[0025] In the mixed region 32, it is preferable that the metal contained in the first conductive material 12 and the metal contained in the second conductive material 22 are mixed. In the mixed region 32, by mixing the metals, the bonding strength is ensured, and as a result, an electrical circuit connection portion 31 having excellent durability (long life, electrical characteristics (conductivity, insulation), etc.) can be obtained.

[0026] The first conductive material 12 may contain a metal having a lower electrical resistivity than the metal contained in the second conductive material 22, or may contain a metal having a higher electrical resistivity than the metal contained in the second conductive material 22. When the electrical circuit connection portion 31 is used for a heater, it is preferable that the first conductive material 12 contains a metal having a higher electrical resistivity than the metal contained in the second conductive material 22. Thereby, the heating stability of the electrode circuit 10 is improved, and as a result, the durability of the electrical circuit connection portion 31 is improved. When the electrical circuit connection portion 31 is used for an electrode of an electrostatic chuck, it is preferable that the first conductive material 12 contains a metal having a higher electrical resistivity than the metal contained in the second conductive material 22. Thereby, the power loss in the electrical circuit connection portion 31 is reduced, and as a result, the durability of the electrical circuit connection portion 31 is improved. Further, the first conductive material 12 may contain both a metal having a lower electrical resistivity than the metal contained in the second conductive material 22 and a metal having a higher electrical resistivity than the metal contained in the second conductive material 22.

[0027] The second conductive material 22 may contain a metal with a lower electrical resistivity than the metal contained in the first conductive material 12, or it may contain a metal with a higher electrical resistivity than the metal contained in the first conductive material 12. When the electrical circuit connection part 31 is used in a heater, it is preferable that the second conductive material 22 contains a metal with a lower electrical resistivity than the metal contained in the first conductive material 12. This improves the heating stability of the electrode circuit 10, and as a result, improves the durability of the electrical circuit connection part 31. When the electrical circuit connection part 31 is used as an electrode for an electrostatic chuck, it is preferable that the second conductive material 22 contains a metal with a lower electrical resistivity than the metal contained in the first conductive material 12. This reduces power loss in the electrical circuit connection part 31, and as a result, improves the durability of the electrical circuit connection part 31. Furthermore, the second conductive material 22 may contain both a metal with a lower electrical resistivity than the metal contained in the first conductive material 12 and a metal with a higher electrical resistivity than the metal contained in the first conductive material 12.

[0028] It is preferable that multiple mixed regions 32 are formed between the electrode conductor 11 and the connecting conductor 21. As described above, the mixed region 32 is a joint where the first conductive material 12 and the second conductive material 22 are mixed and joined together. It is preferable that there are two or more mixed regions 32 in one electrical circuit connection 31, and more preferably three or more. Having multiple mixed regions 32 in the electrical circuit connection 31 makes the coupling of the connecting conductor 21 to the electrode conductor 11 more stable.

[0029] Non-joint portions 33 may be interposed between the multiple mixed regions 32, where the electrode conductor 11 and the connecting conductor 21 are not joined. By having non-joint portions 33 between the multiple mixed regions 32 in the electrical circuit connection portion 31, the range over which multiple joined mixed regions 32 exist is expanded, making it easier to distribute the forces acting on the electrical circuit connection portion 31. As a result, an electrical circuit connection portion 31 with superior durability (long lifespan, electrical characteristics (conductivity, insulation), etc.) can be obtained.

[0030] The method for forming the mixed region 32 is not particularly limited, but it may be formed by welding the first conductive material 12 and the second conductive material 22. When conductive materials such as metals are welded, at least one of the first conductive material 12 and the second conductive material 22 can be melted. This promotes the mixing of the first conductive material 12 and the second conductive material 22. In welding metallic materials, the metallic material may be heated or pressurized. In this embodiment, "welding" refers to the operation of joining the electrode conductor 11 and the connecting conductor 21 by heat, pressure, or both, so that they have continuity.

[0031] As for the welding method, it is sufficient to supply at least one of the members to be welded (electrode conductor 11 or connecting conductor 21) by transferring or converting the energy necessary for welding the conductive material. Specific examples include resistance welding using current, laser welding using laser irradiation, arc welding using an electric arc, electron beam welding using an electron beam, and optical beam welding using an optical beam.

[0032] Spot welding, which involves concentrating current and pressure locally, is preferable because it facilitates the formation of small electrical circuit connection parts 31, thus easily achieving both durability and miniaturization of the electrical circuit connection parts 31. Depending on the shape of the member to be welded and the welding area, projection welding, which involves forming a protrusion on the member to be welded and applying current, or seam welding, which involves continuously applying current while moving the member to be welded, may also be employed.

[0033] (Electrode Sheet and Connecting Sheet) The electrode conductor 11 is preferably an electrode sheet 15 made of a first conductive material 12. The electrode sheet 15 is a sheet having a width and length and spreading along its surface. The planar shape of the electrode sheet 15 can be, for example, a disc, annular, strip, rectangular, or a wiring (comb shape, etc.) with a portion of these shapes cut out, but is not limited to these. Compared to cases where the electrode conductor 11 is fibrous, stranded, etc., the electrode sheet 15 can operate stably over a wider area. The ratio of width to length in the electrode conductor 11 is not particularly limited; the width may be about the same as the length, the length may be greater than the width, or the width may be greater than the length. The thickness of the electrode conductor 11 in the electrode sheet 15 can also be set as appropriate.

[0034] The connecting conductor 21 is preferably a connecting sheet 25 made of a second conductive material 22. The connecting sheet 25 is a sheet having a width and length and spreading along its surface. The planar shape of the connecting sheet 25 can be, for example, a disc, annular, strip, rectangular, or a wiring (comb shape, etc.) with a portion of these shapes cut out. However, it is not limited to these. Compared to cases where the connecting conductor 21 is fibrous, stranded, etc., the connecting sheet 25 can be joined to the electrode conductor 11 over a wider area. The ratio of width to length in the connecting conductor 21 is not particularly limited; the width may be about the same as the length, the length may be greater than the width, or the width may be greater than the length. The thickness of the connecting conductor 21 in the connecting sheet 25 can also be set as appropriate.

[0035] The mixed region 32 formed between the electrode sheet 15 and the connecting sheet 25 is preferably formed between one side of the electrode sheet 15 in the thickness direction and one side of the connecting sheet 25 in the thickness direction. In the example shown in Figure 1, the connecting sheet 25 is bent with respect to the surface direction of the electrode sheet 15, as shown in the electrical circuit connection portion 31A in Figure 4.

[0036] Although not specifically shown in the figures, the electrode sheet 15 may be bent in the planar direction of the connecting sheet 25, and both the electrode sheet 15 and the connecting sheet 25 may be bent in the plane including the electrical circuit connection portion 31. Alternatively, as shown in the electrical circuit connection portion 31B in Figure 5, the electrode sheet 15 and the connecting sheet 25 may not be bent, and a mixed region 32 may be formed.

[0037] The form of the mixed region 32 formed between the electrode sheet 15 and the connecting sheet 25 is not limited to the above examples and may include butt joints at the edges of the sheets. As shown in the electrical circuit connection portion 31C in Figure 6, the longitudinal edge of the connecting sheet 25 may be butted against one side in the thickness direction of the electrode sheet 15 and joined together. Alternatively, although not shown, the longitudinal edge of the electrode sheet 15 may be butted against one side in the thickness direction of the connecting sheet 25 and joined together. Furthermore, as shown in the electrical circuit connection portion 31D in Figure 7, the longitudinal edges of both the electrode sheet 15 and the connecting sheet 25 may be butted against each other and joined together. Although not shown, the mixed region 32 shown in Figures 4 to 7 may also include multiple mixed regions 32 and non-joint portions 33 as shown in Figure 1.

[0038] In a field of view perpendicular to the electrode sheet 15, the area of ​​each mixed region 32 is 0.0001 mm². ２ 0.5 mm or more ２ Preferably, it is within the following range: 0.001 mm ２ 0.2 mm or more ２ The following is also acceptable: 0.01 mm ２ 0.1 mm or more ２ The following are also acceptable. If the area of ​​each mixed region 32 is greater than or equal to the lower limit, it tends to be easier to ensure the strength of the mixed region 32 that forms the joint. If the area of ​​each mixed region 32 is less than or equal to the upper limit, it tends to be easier to achieve both durability and miniaturization of the electrical circuit connection part 31.

[0039] When multiple mixed regions 32 are formed on the electrode sheet 15 for a single electrical circuit connection portion 31, it is preferable that the shortest distance between adjacent mixed regions 32 in a field of view perpendicular to the electrode sheet 15 is within the range of 0.05 mm to 5.0 mm, and may also be within the range of 0.1 mm to 3.0 mm. When the shortest distance between adjacent mixed regions 32 is above the lower limit, it tends to be easier to ensure the strength of the mixed region 32 that forms the joint. When the shortest distance between adjacent mixed regions 32 is below the upper limit, it tends to be easier to achieve both durability and miniaturization of the electrical circuit connection portion 31.

[0040] As shown in Figure 1, the electrode conductor 11 may have irregularities 34 around the region where it is joined to the connecting conductor 21. The irregularities 34 may be formed as a result of welding. Preferably, the irregularities 34 of the electrode conductor 11 are formed around the region where it is joined to the connecting sheet 25 when the electrode conductor 11 is a sheet-like electrode sheet 15. The presence of irregularities 34 on the electrode sheet 15 can alleviate external stress on the electrical circuit connection portion 31. As a result, the durability of the electrical circuit connection portion 31 is improved.

[0041] As shown in Figure 2, the illustrated electrode circuit 10 includes an insulating resin film 13 laminated on an electrode sheet 15. If the electrode sheet 15 is made of a material that can be handled on its own, such as a metal foil or a graphite sheet, the insulating resin film 13 may be attached to one side of the electrode sheet 15. If the electrode sheet 15 is made of a material formed by a film-forming method on a substrate, such as a metal plating layer or a metal vapor deposition layer, the insulating resin film 13 may be the substrate used when forming the electrode sheet 15.

[0042] Preferably, the insulating resin film 13 is laminated on the surface 15b of the electrode sheet 15 opposite to the surface 15a that is joined to the connecting sheet 25. In the step of joining the electrode sheet 15 to the connecting sheet 25, the surface 15a of the electrode sheet 15 that is joined to the connecting sheet 25 is exposed, and the insulating resin film 13 may be laminated only on the opposite surface 15b.

[0043] After the connecting sheet 25 has been joined to the electrode sheet 15, an insulating resin layer 16, such as an insulating resin film, may be optionally laminated to either the surface 15a of the electrode sheet 15 that is joined to the connecting sheet 25, or the opposite surface 15b. To laminate the insulating resin layer 16 to the electrode sheet 15, an adhesive layer 17 may be interposed between the two.

[0044] In the illustrated electrode circuit 10, the insulating resin film 13 has a notch 14. Specifically, the notch 14 is formed such that, in a planar view from a direction perpendicular to the surface 15a of the electrode sheet 15 that is joined to the connecting sheet 25 or the opposite surface 15b, the insulating resin film 13 does not overlap with the area where it is joined to the connecting sheet 25. As a result, there is no material of the insulating resin film 13 in the area where the electrode sheet 15 is joined to the connecting sheet 25, so the flexibility of the electrode circuit 10 is maintained and external stress on the electrode circuit 10 and the electrical circuit connection part 31 can be reduced. In addition, the process of connecting the electrode sheet 15 to the connecting sheet 25 is made easier.

[0045] The insulating resin film 13 preferably has one or more of the insulating resins consisting of polyimide, polyetheretherketone, polyphenylene sulfide, polyamideimide, liquid crystal polymer, fluoropolymer, polyester resin, and polystyrene resin. The insulating resin film 13 may use only one or more films from the insulating resins, or it may be used by laminating one or more films from the insulating resins with other resin films.

[0046] (Conductive Sheet) The conductive sheet 30 of this embodiment comprises a sheet-shaped electrode circuit 10 and a sheet-shaped connection circuit 20, and further comprises an electrical circuit connection portion 31 of this embodiment between the electrode circuit 10 and the connection circuit 20.

[0047] As shown in Figure 2, the conductive sheet 30 includes an electrical circuit connection portion 31 between the electrode sheet 15 and the connecting sheet 25. The conductive sheet 30 in the illustrated example has an extension portion 23 from which a connecting conductor 21 extends from the main body portion 24 of the connecting circuit 20. The extension portion 23 can be made from a part of the connecting sheet 25. The width of the connecting conductor 21 in the extension portion 23 may be the same as the width of the connecting sheet 25 in the main body portion 24. A part in the width direction may be cut off at the longitudinal end of the connecting sheet 25, making the width of the connecting conductor 21 in the extension portion 23 smaller than the width of the connecting sheet 25 in the main body portion 24.

[0048] The main body 24 of the connection circuit 20, like the electrode circuit 10, may optionally have an insulating resin layer 26, such as an insulating resin film, laminated on at least one surface (both sides in the illustrated example) of the connection sheet 25. To laminate the insulating resin layer 26 onto the connection sheet 25, an adhesive layer 27 may be interposed between the two.

[0049] In this embodiment, it is preferable that at least one of the electrode circuit 10 or the connection circuit 20 of the conductive sheet 30 includes insulating resin layers 16 and 26. Examples of insulating resin layers 16 and 26 include the attachment of an insulating resin film and the coating of an insulating resin paint. The insulating resin layers 16 and 26, such as an insulating resin film, may be attached to the electrode sheet 15 or the connection sheet 25 via adhesive layers 17 and 27. Alternatively, a heat-adhesive insulating resin film may be attached to the electrode sheet 15 or the connection sheet 25 without the use of adhesive layers 17 and 27.

[0050] The insulating resin constituting the insulating resin layers 16 and 26 is not particularly limited, but examples include thermoplastic resins, thermosetting resins, and photocurable resins. Specific examples of insulating resins include polyesters such as polyethylene terephthalate, polyolefins such as polyethylene, polyimide, polyamide, polyamide-imide, polyethersulfone, polyphenylene sulfide, polyetherketone, polyetherimide, triacetylcellulose, silicone rubber, and fluorine-based resins such as polytetrafluoroethylene.

[0051] The resin constituting the adhesive layers 17 and 27 is not particularly limited as long as it has electrical insulation properties, and examples thereof include epoxy resins, phenolic resins, styrene block copolymers, polyamide resins, acrylonitrile-butadiene copolymers, polyester resins, polyimide resins, silicone resins, amine compounds, bismaleimide compounds, and the like. These resins may be used alone or in combination of two or more.

[0052] A ceramic layer may be laminated on the electrode circuit 10 or the connection circuit 20, or ceramic particles may be added to the insulating resin layers 16 and 26 or the adhesive layers 17 and 27. Specific examples of the ceramics that can be used for the electrode circuit 10 or the connection circuit 20 include oxide-based ceramics and non-oxide-based ceramics. These ceramic materials may be used alone or in combination of two or more.

[0053] The oxide-based ceramics are not particularly limited, but examples include aluminum oxide (Al ２ O ３ ), zirconium oxide (ZrO ２ ), yttrium oxide (Y ２ O ３ ), talc (hydrous magnesium silicate, Mg ３ Si ４ O １０ (OH) １０ ), hematite (iron(III) oxide, Fe ２ O ３ ), chromium(III) oxide (Cr ２ O ３ ), titanium(IV) oxide (TiO ２ ), magnesium oxide (MgO), silicon dioxide (SiO ２ ), calcium oxide (CaO), cerium(IV) oxide (CeO ２ ), steatite (magnesium metasilicate, MgO·SiO ２ ), cordierite (2MgO·2Al ２ O ３ ·5SiO ２ ), mullite (3Al ２ O ３ ·2SiO ２ ), ferrite (MnFe２ O ４ (etc.), zircon (ZrSiO ４ ), barium titanate (BaTiO ３ ), lead titanate (PbTiO ３ ), forsterite (Mg ２ SiO ４ Examples include phosphorus-doped tin oxide (PTO) and antimond-doped tin oxide (ATO).

[0054] Non-oxide ceramics are not particularly limited, but examples include nitride ceramics, silicate compound ceramics, and phosphate compounds. Examples of nitride ceramics include boron nitride (BN), titanium nitride (TiN), and silicon nitride (Si ３ N ４ Examples of silicate compounds include gallium nitride (GaN) and aluminum nitride (AlN). Examples of silicate compounds include zirconium oxide silicate, hafnium oxide silicate, titanium oxide silicate, lanthanum oxide silicate, yttrium oxide silicate, tantalum oxide silicate, and tantalum oxynitride silicate. Examples of phosphorus compounds include hydroxyapatite and calcium phosphate.

[0055] <Electrostatic Chuck or Heater> Figure 3 is a cross-sectional view illustrating an electrode-mounted device 40 that serves as an electrostatic chuck or heater in this embodiment.

[0056] The electrostatic chuck or heater of this embodiment is an electrode-mounted device 40 comprising an electrode circuit 10 and a connection circuit 20, with an electrical circuit connection part 31 of this embodiment between the electrode circuit 10 and the connection circuit 20. The electrode-mounted device 40 is not limited to the electrostatic chuck or heater described above, but may be other electrical equipment.

[0057] The electrode-mounted device 40 in the illustrated example has a mounting layer 42 on which the object to be processed is placed. The mounting layer 42 is formed on the electrode circuit 10. Preferably, the mounting layer 42 has a recess 43 to secure space between it and the object to be processed. This reduces the contact area between the mounting layer 42 and the object to be processed, thereby suppressing damage to the mounting layer 42. As a result, the durability of the electrode-mounted device 40 is improved. Gas may be supplied to the recess 43 for processing, cooling, or other purposes.

[0058] When supplying gas to the recess 43, a gas passage extending vertically from the base 50 (details described later) may be provided. The gas passage may be surrounded by a tubular member such as ceramics, if necessary. In this case, durability and uniform heat distribution of the electrode-mounted device 40 can be achieved simultaneously. Furthermore, notches (not shown), such as through holes, may be provided in each part positioned between the base 50 and the mounting layer 42, for example, the electrode circuit 10, the connection circuit 20, the heat transfer adjustment layer 51, etc., for the purpose of accommodating the gas passage or for other desired purposes.

[0059] The material of the object to be processed by the electrode-equipped device 40 is not particularly limited, but examples include semiconductors such as silicon (Si), glass, ceramics, and insulating materials. The object to be processed may also be a semiconductor wafer.

[0060] The object to be processed by the electrode-mounted device 40 is placed on the mounting layer 42 and processed by the action of the electrode circuit 10. The processing content of the electrode-mounted device 40 is not particularly limited, but examples include electrostatic adsorption, heat treatment, gas treatment, film formation treatment, etching treatment, plasma treatment, etc. Depending on the processing content, the space above the mounting layer 42 may be made into a vacuum (reduced pressure state) or into a predetermined gas atmosphere.

[0061] The mounting layer 42 can be made of a dielectric material such as resin or ceramics. Examples of resins used in the mounting layer 42 include the insulating resins mentioned above. Examples of ceramics used in the mounting layer 42 include the oxide-based ceramics and non-oxide-based ceramics mentioned above. These ceramic materials may be used individually or in mixtures of two or more types.

[0062] (Characteristics of electrostatic chucks and other electrode-mounted devices) When the mounting layer 42 is made of resin, the storage modulus of the resin under 40°C conditions may be 100 MPa or more and 12,000 MPa or less. In this case, damage or deformation of the mounted object and the mounting layer 42 can be suppressed over the long term.

[0063] The measurement of the storage modulus is not particularly limited, but a dynamic viscoelasticity measuring device (for example, HR-20 manufactured by TA Instruments) can be used. For example, the mounting layer 42 can be cut to a predetermined size, and the value can be obtained by measuring under conditions of a heating rate of 5°C / min and a measurement frequency of 10 Hz.

[0064] (Thickness of the mounting layer) The thickness of the mounting layer 42 is not particularly limited, but may be 1 μm to 3000 μm, 5 μm to 1000 μm, 5 μm to 500 μm, 5 μm to 200 μm, 5 μm to 75 μm, or 10 μm to 50 μm. For example, if the electrode mounting device 40 is an electrostatic chuck, a thinner thickness improves the adsorption performance to the object to be mounted, and a thicker thickness increases the strength of the mounting layer 42. In other words, by setting the thickness of the mounting layer 42 within the above range, it is possible to achieve both the functionality (adsorption performance) and durability of the electrode mounting device 40.

[0065] (Adhesion Layer) The electrode-mounted device 40 may have a mounting layer 42 via an adhesion layer 41. The material of the adhesion layer 41 is not particularly limited, but examples include a resin containing at least one of an organic insulating resin or an inorganic insulating resin. Examples of organic insulating resins are not particularly limited, but examples include polyimide resins, epoxy resins, acrylic resins, etc. Examples of inorganic insulating resins are not particularly limited, but examples include silane resins, silicone resins, etc. Here, organic insulating resin means a polymer material containing carbon elements in the main chain, and inorganic insulating resin means a polymer material that does not contain carbon elements in the main chain.

[0066] The adhesion layer 41 may contain at least one of the following: organic or inorganic polysilazane, inorganic powdered filler, and fibrous filler. Examples of powdered fillers are not particularly limited, but include alumina, silica, and yttria. Examples of fibrous fillers are not particularly limited, but include plant fibers such as pulp, inorganic fibers such as alumina, and organic fibers such as aramid and polytetrafluoroethylene.

[0067] (Resistance value) When the electrode-equipped device 40 is a heater, the resistivity of the electrode circuit 10 is preferably greater than the resistivity of the connecting circuit 20, which is 2.0 × 10⁻⁶. －８ Ω・cm or more 1.0×10 －４ It is more preferable that the resistivity is Ω·cm or less. This suppresses heating in the connection circuit 20 and efficiently heats the electrode circuit 10, and as a result, the function of the electrode-equipped device 40 can be used for a long period of time. For example, when the electrode circuit 10 is made of stainless steel (SUS304) foil, the resistivity is 7.2 × 10⁻⁶. －５ It is Ω·cm.

[0068] (Method for measuring resistance) The method for measuring resistance is not particularly limited, but examples include the four-terminal method and the four-probe method. For example, the electrode circuit 10 or the connection circuit 20 can be cut to a predetermined size and measured using the four-terminal method with a resistivity meter (for example, Loresta® GP manufactured by Nitto Seiko Analytech Co., Ltd.).

[0069] (Heat Transfer Adjustment Layer) The electrode-mounted device 40 may have a heat transfer adjustment layer 51 to adjust heat transfer between the mounting layer 42 and the side of the electrode circuit 10 opposite to the mounting layer 42, or on the side of the electrode circuit 10 opposite to the mounting layer 42. This allows the mounting layer 42 of the electrode-mounted device 40 to be heated efficiently, and as a result, the durability of the electrode-mounted device 40 is improved. For example, the electrode-mounted device 40 in the illustrated example has an insulating layer as an example of a heat transfer adjustment layer 51 on the side of the electrode circuit 10 opposite to the mounting layer 42. Other examples of the heat transfer adjustment layer 51 include a heat dissipation layer, a heat absorption layer, a heat diffusion layer, etc. The heat transfer adjustment layer 51 can be made of metal, ceramics, etc. In the heat transfer adjustment layer 51 in the illustrated example, an adhesive layer 18 is provided between the surface of the heat transfer adjustment layer 51 on the mounting layer 42 side and the electrode circuit 10 in order to fix the electrode circuit 10.

[0070] In the illustrated example, the connection circuit 20 is provided on the heat transfer adjustment layer 51 on the side opposite to the side where the electrode circuit 10 is provided. The heat transfer adjustment layer 51 may have a connection circuit installation portion 52 that matches the dimensions of the connection circuit 20 (more specifically, the main body portion 24). This makes it possible to make the height of the lower surface of the heat transfer adjustment layer 51 in the area where the connection circuit 20 is not installed approximately the same as the height of the lower surface of the connection circuit 20 at the connection circuit installation portion 52. In the illustrated example of the heat transfer adjustment layer 51, an adhesive layer 28 is provided between the connection circuit installation portion 52 and the connection circuit 20 in order to fix the connection circuit 20 to the connection circuit installation portion 52.

[0071] The material of the adhesive layers 18 and 28 is not particularly limited, but examples include epoxy resins, phenolic resins, styrene-based block copolymers, polyamide resins, acrylonitrile-butadiene copolymers, polyester resins, polyimide resins, silicone resins, amine compounds, and bismaleimide compounds. These resins may be used individually or in combination of two or more.

[0072] The heat transfer adjustment layer 51 in the illustrated example has a notch 53 that accommodates the extension portion 23 of the connection circuit 20. The notch 53 is sealed using a sealing material 54 such as an insulating resin. The sealing material 54 is not particularly limited, but examples include thermoplastic resins, thermosetting resins, and photocurable resins.

[0073] The sealing material 54 should be used to the extent that it can suppress the intrusion of foreign matter into the notch 53 of the heat transfer adjustment layer 51. The sealing material 54 may be filled to the extent that no void remains in the notch 53, or voids that do not contain the sealing material 54 may remain in the notch 53. The sealing material 54 that seals the notch 53 may also serve the function of fixing the extension 23 to the inner wall of the notch 53 in the heat transfer adjustment layer 51.

[0074] The sealing material 54 is not particularly limited, but it is preferable that it contains resin. By sealing the electrical circuit connection portion 31 with the sealing material 54, external stress on the electrical circuit connection portion 31 can be relieved. In the illustrated example, external stress on the extended portion 23 of the conductive sheet 30 can also be relieved.

[0075] (Base) The electrode-mounted device 40, such as an electrostatic chuck, may have a base 50. The material of the base 50 is not particularly limited, but it can be made from the oxide ceramics, non-oxide ceramics, or metals and alloys such as aluminum and stainless steel.

[0076] When the conductive sheet 30 of this embodiment is incorporated into the electrode-mounted device 40, the connection circuit 20 of the conductive sheet 30 is connected to a power supply device (not shown) on the base 50, and power can be supplied to the electrode conductor 11 via the connecting conductor 21. The heat transfer adjustment layer 51 and the connection circuit 20 are fixed to the base 50. At this time, the heat transfer adjustment layer 51 and the connection circuit 20 may also be fixed to the base 50 via a fixed layer 55.

[0077] The material of the fixed layer 55 is not particularly limited, but examples include resins, metals (solder, filler material, flux, etc.). Examples of resins include epoxy resins, phenolic resins, styrene-based block copolymers, polyamide resins, acrylonitrile-butadiene copolymers, polyester resins, polyimide resins, silicone resins, fluororesins, amine compounds, and bismaleimide compounds. These resins may be used individually or in mixtures of two or more.

[0078] The electrode-mounted device 40 may be equipped with two or more types of electrode conductors 11. Two or more types of electrode conductors 11 may be arranged between the base 50 and the mounting layer 42. The arrangement of the two or more types of electrode conductors 11 is not particularly limited, but the electrode conductors 11 may be arranged horizontally at the same height from the base 50, or the electrode conductors 11 may be stacked vertically at different heights from the base 50. For example, if the electrode-mounted device 40 is equipped with an electrode for an electrostatic chuck and an electrode for a heater, the electrical circuit connection part 31 and conductive sheet 30 of this embodiment may be applied to supply power to the electrostatic chuck electrode and the heater electrode, respectively.

[0079] At least one of the adhesive layers 17, 18, 27, 28, the bonding layer 41, and the fixing layer 55 may be an adhesive sheet made of an adhesive resin. Preferably, the adhesive sheet has the function of bonding and fixing the members by overlapping them without solvents.

[0080] (Method for manufacturing the electrode-mounted device 40) The method for manufacturing the electrode-mounted device 40 is not particularly limited, but for example, when manufacturing an electrostatic chuck equipped with a heater, it can be manufactured by the following method.

[0081] Specifically, a double-sided adhesive sheet is prepared by heat-bonding an adhesive film to both sides of a polyimide film (Toray DuPont, Kapton® 100EN, 25 μm thick). Here, the adhesive film is prepared by coating and drying a thermoplastic polyimide varnish (Arakawa Chemical Co., Ltd., PIAD® 100H) so that its thickness after drying is 10 μm. Four of these double-sided adhesive sheets are punched out into a disc shape (300 mm in diameter), and one is used as is. Then, of the remaining three, 10 mmφ openings are made in predetermined positions (positions for the first and second connection circuits) on two of them (first double-sided adhesive sheet). Similarly, a 10 mmφ opening is made in a predetermined position (only in the position for the second connection circuit) on the other sheet (second double-sided adhesive sheet).

[0082] Next, one stainless steel plate (heat transfer adjustment layer, SUS316, 5.0 mm thick) of the same shape as the first double-sided adhesive sheet is prepared, one disc-shaped first stainless steel foil (heater electrode, 300 mm in diameter, SUS304-H, 20 μm thick) with an opening at the position where the second connection circuit will be installed is prepared, and one disc-shaped second stainless steel foil (adsorption electrode, 300 mm in diameter, SUS304-H, 20 μm thick) is prepared. Here, the first double-sided adhesive sheet and the first stainless steel foil are heated and laminated in that order on one side of the stainless steel plate (first laminate), and the first connection circuit (copper foil, 20 μm thick) is inserted into the opening (first connection circuit installation area, heater electrode) provided on the side of the stainless steel plate opposite to the side on which the first double-sided adhesive sheet is laminated, and the first connection circuit and the first stainless steel foil are joined in three places by spot welding so as to sandwich the first connection circuit and the first stainless steel foil (first electrical circuit connection area). At this time, the mixed regions formed at each junction are not in contact with each other.

[0083] Next, the second double-sided adhesive sheet and the second stainless steel foil are heat-laminated on the first stainless steel foil side of the first laminate in that order (second laminate). The second connection circuit (copper foil, 20 μm thick) is inserted into another opening (second connection circuit installation section, adsorption electrode) provided on the side of the stainless steel plate opposite to the side where the first double-sided adhesive sheet is laminated. The second connection circuit and the second stainless steel foil are then joined at three points by spot welding in the same manner as described above (second electrical circuit connection section).

[0084] Subsequently, a disc-shaped double-sided adhesive sheet and a disc-shaped polyimide film (300 mm in diameter) are heat-laminated in that order onto the second stainless steel foil side of the second laminate (third laminate). Then, a mixed sealing material (Shin-Etsu Chemical Co., Ltd., two-component curing type silicone resin, KE-1066-A / B) is filled into the openings into which the first and second connection circuits are inserted and cured. Finally, the stainless steel plate side of the third laminate is placed on the base via the first double-sided adhesive sheet to create an electrostatic chuck (electrode-mounted device 40). Power supply devices can be connected to each connection circuit and used. When multiple electrode circuits coexist, their positions are not particularly limited as long as there are no functional problems.

[0085] The electrode-mounted device 40 in the above manufacturing example generally has the following laminated structure: • Disc-shaped polyimide film (mounting layer 42) • Disc-shaped double-sided adhesive sheet (adhesion layer 41) • Second stainless steel foil (second electrode circuit 10; second connection circuit 20 connected from the base 50 side via second electrical circuit connection part 31) • Second double-sided adhesive sheet (adhesion layer between electrode circuits) • First stainless steel foil (first electrode circuit 10; first connection circuit 20 connected from the base 50 side via first electrical circuit connection part 31) • First double-sided adhesive sheet (adhesion layer 18) • Stainless steel plate (heat transfer adjustment layer 51) • First double-sided adhesive sheet (fixing layer 55) • Base 50

[0086] Although the present invention has been described above based on preferred embodiments, the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention. Modifications include adding, substituting, omitting, or otherwise changing the components in each embodiment.

[0087] According to the present invention, it is possible to provide an electrical circuit connection part, a conductive sheet, an electrostatic chuck, and a heater that can connect electrode circuits and connection circuits well and have excellent durability (long lifespan, electrical characteristics (conductivity, insulation), etc.).

[0088] 10... Electrode circuit, 11... Electrode conductor, 12... First conductive material, 13... Insulating resin film, 14... Notch, 15... Electrode sheet, 15a... Joined surface, 15b... Opposite surface, 16... Insulating resin layer, 17, 18... Adhesive layer, 20... Connection circuit, 21... Connection conductor, 22... Second conductive material, 23... Extension, 24... Main body, 25... Connection sheet, 26... Insulating resin layer, 27, 28... Adhesive layer, 30... Conductive sheet, 31, 31A, 31B, 31C, 31D... Electrical circuit connection part, 32... Mixed area, 33... Non-joined part, 34... Uneven surface, 40... Electrode mounting equipment, 41... Adhesion layer, 42... Mounting layer, 43... Recess, 50... Base, 51... Heat transfer adjustment layer, 52... Connection circuit installation part, 53... Notch, 54... Sealing material, 55... Fixing layer.

Claims

1. An electrical circuit connection part for connecting an electrode circuit and a connecting circuit, wherein the electrode circuit has an electrode conductor made of a first conductive material, the connecting circuit has a connecting conductor made of a second conductive material, and the electrical circuit connection part has a mixed region between the electrode conductor and the connecting conductor, the mixed region being made of a material contained in the first conductive material and the second conductive material, in which the first conductive material and the second conductive material are mixed and joined.

2. The electrical circuit connection part according to claim 1, characterized in that in the mixed region, the metal contained in the first conductive material and the metal contained in the second conductive material are mixed together.

3. The electrical circuit connection part according to claim 1, characterized in that the first conductive material includes a metal with a lower electrical resistivity than the metal contained in the second conductive material.

4. The electrical circuit connection part according to claim 1, characterized in that the first conductive material includes a metal with a higher electrical resistivity than the metal contained in the second conductive material.

5. The electrical circuit connection part according to claim 1, characterized in that a plurality of mixed regions are formed between the electrode conductor and the connecting conductor, and non-jointed portions are interposed between these plurality of mixed regions where the electrode conductor and the connecting conductor are not joined.

6. The electrical circuit connection portion according to claim 1, characterized in that the mixed region is formed by welding the first conductive material and the second conductive material.

7. The electrical circuit connection part according to claim 1, characterized in that the electrode conductor is an electrode sheet made of the first conductive material, the connecting conductor is a connecting sheet made of the second conductive material, and the mixed region is formed between one side in the thickness direction of the electrode sheet and one side in the thickness direction of the connecting sheet.

8. In a field of view perpendicular to the electrode sheet, the area of ​​each of the mixed regions is 0.0001 mm². ２ 0.5 mm or more ２ The electrical circuit connection part according to claim 7, characterized in that it is within the following range, and the shortest distance between adjacent mixed regions is within the range of 0.05 mm to 5.0 mm.

9. The electrical circuit connection portion according to claim 7, characterized in that the electrode sheet has irregularities around the region to be joined with the connecting sheet.

10. The electrical circuit connection part according to claim 7, characterized in that the electrode circuit includes an insulating resin film laminated on the electrode sheet.

11. A conductive sheet comprising a sheet-shaped electrode circuit and a sheet-shaped connection circuit, wherein the electrode circuit and the connection circuit are provided with the electrical circuit connection portion described in claim 1.

12. The conductive sheet according to claim 11, characterized in that at least one of the electrode circuit or the connection circuit includes an insulating resin layer.

13. The conductive sheet according to claim 12, characterized in that at least one of the electrode circuit or the connection circuit includes an insulating resin film.

14. An electrostatic chuck comprising an electrode circuit and a connection circuit, wherein an electrical circuit connection portion according to any one of claims 1 to 10 is provided between the electrode circuit and the connection circuit.

15. A heater comprising an electrode circuit and a connection circuit, wherein an electrical circuit connection portion according to any one of claims 1 to 10 is provided between the electrode circuit and the connection circuit.

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