Multilayer substrate

Abstract

The purpose of the present invention is to reduce AC resistance. In a multilayer substrate (100), a plurality of ground electrodes (41-44) are separated from each other in the thickness direction (D1) of a laminated substrate (1), and are adjacent to a plurality of signal lines (21-24) in the width direction of the plurality of signal lines (21-24). In a first transmission line region where the maximum line width of the plurality of signal lines (21-24) is minimum, the plurality of signal lines (21-24) do not overlap with any one of the plurality of ground electrodes (41-44) in the thickness direction (D1) of the laminated substrate (1). In a second transmission line region (102) in which the maximum line width of the plurality of signal lines (21-24) is the largest, one ground electrode (41) among the plurality of ground electrodes (41-44) overlaps with signal lines (22-24) other than the signal line (21) adjacent to the one ground electrode (41) among the plurality of signal lines (21-24).

Description

Technical Field

[0001] This invention generally relates to multilayer substrates, and more specifically to multilayer substrates having AC signal lines. Background Technology

[0002] Patent document 1 discloses a multilayer substrate comprising a laminate (laminated substrate), three signal conductors (signal lines), and six ground conductors.

[0003] The laminate has a structure in which multiple resin layers (insulating layers) are stacked in the stacking direction. The three signal conductors are positioned differently in the stacking direction. The three signal conductors are electrically connected. In the multilayer substrate disclosed in Patent Document 1, when viewed from the stacking direction, the ground conductor is located on both sides of the width direction of each of the three signal conductors. High-frequency signals are transmitted through the three signal conductors.

[0004] Prior art literature

[0005] Patent documents

[0006] Patent Document 1: International Publication No. 2023 / 037852 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] In the multilayer substrate disclosed in Patent Document 1, the grounding conductor is located on both sides of the width direction of each of the three signal conductors. Therefore, due to the proximity effect, the current in each of the three signal conductors is concentrated at both ends in the width direction, and the AC resistance becomes high.

[0009] The purpose of this invention is to provide a multilayer substrate capable of reducing AC resistance.

[0010] Technical solutions for solving the problem

[0011] One aspect of the present invention relates to a multilayer substrate comprising a stacked substrate, an AC signal line, and a plurality of ground electrodes. The stacked substrate has a plurality of insulating layers. The AC signal line is formed on the stacked substrate. The AC signal line has a plurality of signal lines separated from each other in the thickness direction of the stacked substrate, and the plurality of signal lines are electrically connected by a plurality of connecting conductors passing through one of the plurality of insulating layers in the thickness direction. The plurality of ground electrodes are formed on the stacked substrate. The plurality of ground electrodes are separated from each other in the thickness direction and are adjacent to the plurality of signal lines in the width direction. In a first transmission line region where the maximum line width of the plurality of signal lines is the smallest, the plurality of signal lines do not overlap with any of the plurality of ground electrodes in the thickness direction. In a second transmission line region where the maximum line width of the plurality of signal lines is the largest, one of the plurality of ground electrodes overlaps with a signal line other than the signal line adjacent to the one ground electrode.

[0012] Invention Effects

[0013] The multilayer substrate described above by the present invention can reduce AC resistance. Attached Figure Description

[0014] Figure 1 This is a top view of a portion of the multilayer substrate involved in Embodiment 1.

[0015] Figure 2 The above refers to multilayer substrates, which are Figure 1 Sectional view along line II-II.

[0016] Figure 3 The above refers to multilayer substrates, which are Figure 1 Sectional view along line III-III.

[0017] Figure 4 The diagram above shows a top view of both the transmission line area and the mounting area on the same multilayer substrate.

[0018] Figure 5 The above-mentioned multilayer substrate is a graph showing the relationship between AC resistance and signal line width.

[0019] Figure 6 This is a top view of a portion of the multilayer substrate involved in Embodiment 2.

[0020] Figure 7 The above refers to multilayer substrates, which are Figure 6 Sectional view along line VII-VII.

[0021] Figure 8 The above refers to multilayer substrates, which are Figure 6 Sectional view along line VIII-VIII.

[0022] Figure 9 This is a top view of a portion of the multilayer substrate involved in Embodiment 3.

[0023] Figure 10 The above refers to multilayer substrates, which are Figure 9 XX-line sectional view.

[0024] Figure 11 The above refers to multilayer substrates, which are Figure 9 Sectional view along line XI-XI.

[0025] Figure 12 This is a top view of a portion of the multilayer substrate involved in Embodiment 4.

[0026] Figure 13 The above refers to multilayer substrates, which are Figure 12 Sectional view along line XIII-XIII.

[0027] Figure 14 The above refers to multilayer substrates, which are Figure 12 Sectional view along line XIV-XIV.

[0028] Figure 15 This is a top view of a portion of the multilayer substrate involved in Embodiment 5.

[0029] Figure 16 The above refers to multilayer substrates, which are Figure 15 XVI-XVI line sectional view.

[0030] Figure 17 The above refers to multilayer substrates, which are Figure 15 Sectional view along line XVII-XVII.

[0031] Figure 18 This is a top view of a portion of the multilayer substrate involved in Embodiment 6.

[0032] Figure 19 This is a top view of the second signal line, the second ground electrode, and the RF signal line through the multilayer substrate shown above.

[0033] Figure 20 The above refers to multilayer substrates, which are Figure 18 Sectional view along line XX-XX.

[0034] Figure 21 The above refers to multilayer substrates, which are Figure 18 A cross-sectional view along line XXI-XXI.

[0035] Figure 22This is a top view of a portion of the multilayer substrate involved in Embodiment 7.

[0036] Figure 23 This is a top view of the second signal line, the second ground electrode, and the RF signal line through the multilayer substrate shown above.

[0037] Figure 24 The above refers to multilayer substrates, which are Figure 22 Sectional view along line XXIV-XXIV.

[0038] Figure 25 The above refers to multilayer substrates, which are Figure 22 XXV-XXV line sectional view.

[0039] Figure 26 This is a cross-sectional view of the multilayer substrate according to Embodiment 8.

[0040] Figure 27 This is a top view of a portion of the multilayer substrate involved in Embodiment 9.

[0041] Figure 28 This is a top view of the second signal line, the second ground electrode, and the RF signal line through the multilayer substrate shown above.

[0042] Figure 29 The above refers to multilayer substrates, which are Figure 27 XXIX-XXIX line section view.

[0043] Figure 30 The above refers to multilayer substrates, which are Figure 27 Sectional view along line XXX-XXX.

[0044] Figure 31 This is a top view of a portion of the multilayer substrate involved in Embodiment 10.

[0045] Figure 32 The above refers to multilayer substrates, which are Figure 31 Sectional view along line XXXII-XXXII.

[0046] Figure 33 The above refers to multilayer substrates, which are Figure 31 Sectional view along line XXXIII-XXXIII.

[0047] Figure 34 The above-mentioned multilayer substrate is shown in a main perspective top view illustrating the location of the connecting conductors near the boundary region between the first transmission line region and the second transmission line region.

[0048] Figure 35 This is a top view of a portion of the multilayer substrate involved in Embodiment 11.

[0049] Figure 36 The above refers to multilayer substrates, which are Figure 35 Sectional view along line XXXVI-XXXVI.

[0050] Figure 37 The above refers to multilayer substrates, which are Figure 35 Sectional view along line XXXVII-XXXVII. Detailed Implementation

[0051] Hereinafter, embodiments 1 to 11 will be described with reference to the accompanying drawings. The drawings referred to in embodiments 1 to 11 below are schematic drawings, and the size and thickness of the constituent elements in the drawings may not necessarily reflect the actual dimensions, and the size ratio and thickness ratio between the constituent elements may not necessarily reflect the actual size ratio.

[0052] (Implementation Method 1)

[0053] Reference Figures 1-5 The multilayer substrate 100 according to Embodiment 1 will be described.

[0054] (1) Structure of multilayer substrate

[0055] like Figures 1-3 As shown, the multilayer substrate 100 according to Embodiment 1 includes a stacked substrate 1, an AC signal line 2, and a plurality of (in) Figure 2 In the example, there are four grounding electrodes 41 to 44. For example, as... Figure 4 As shown, the multilayer substrate 100 has a first transmission line region 101, a second transmission line region 102, a first mounting region 111, and a second mounting region 112, but in Figure 1 The portions of the multilayer substrate 100 including the first mounting region 111 and the portion including the second mounting region 112 are omitted from the illustration. Figure 1 as well as Figure 4In the diagram, the boundary BL1 between the first transmission line region 101 and the second transmission line region 102 is illustrated with a dashed line; however, this boundary BL1 is a hypothetical boundary illustrated for illustrative purposes. The first mounting region 111 is the region where a first electronic component (e.g., a connector) is configured to connect the first terminal of the AC signal line 2 and the first terminals of each of the plurality of ground electrodes 41-44. The term "first electronic component configured in the first mounting region 111" includes both cases where the first electronic component is mechanically connected to the multilayer substrate 100 and cases where the first electronic component is electrically connected to the AC signal line 2. The second mounting region 112 is the region where a second electronic component (e.g., a connector) is configured to connect the second terminal of the AC signal line 2 and the second terminals of each of the plurality of ground electrodes 41-44. The term "second electronic component configured" includes both cases where the second electronic component is mechanically connected to the multilayer substrate 100 and cases where the second electronic component is electrically connected to the AC signal line 2.

[0056] exist Figures 1-4 In each figure, orthogonal coordinates with three mutually orthogonal axes—X-axis, Y-axis, and Z-axis—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 2 The axis is labeled Z-axis. The X, Y, and Z axes are all imaginary axes; the arrows showing "X," "Y," and "Z" in the accompanying drawings are merely illustrative and do not represent actual axes. The multilayer substrate 100 is, for example, a flexible substrate. Figure 1 In the example, the thickness direction D1 of the multilayer substrate 100 is along the Z-axis, but it varies depending on the position of the multilayer substrate 100 when the multilayer substrate 100 is bent.

[0057] The multilayer substrate 100 is, for example, housed in the casing of an electronic device. The electronic device is, for example, a communication device. The communication device is, for example, a mobile phone (e.g., a smartphone), but is not limited to a mobile phone; for example, it could also be a laptop computer, a wearable terminal (e.g., a smartwatch), etc.

[0058] (1.1) Laminated substrate

[0059] like Figure 2 as well as Figure 3 As shown, the laminated substrate 1 has multiple (in Figure 2 as well as Figure 3 In this example, there are four insulating layers 11, 12, 13, and 14, and multiple insulating layers 11, 12, 13, and 14 are stacked. The thickness direction D1 of the laminated substrate 1 is the stacking direction of the multiple insulating layers 11, 12, 13, and 14. Hereinafter, for ease of explanation, insulating layers 11, 12, 13, and 14 will sometimes be referred to as the first insulating layer 11, the second insulating layer 12, the third insulating layer 13, and the fourth insulating layer 14, respectively.

[0060] In the laminated substrate 1, the first insulating layer 11, the second insulating layer 12, the third insulating layer 13 and the fourth insulating layer 14 are stacked in the order of the first insulating layer 11, the second insulating layer 12, the third insulating layer 13 and the fourth insulating layer 14.

[0061] Each of the plurality of insulating layers 11, 12, 13, and 14 is made of, for example, a thermoplastic resin. The thermoplastic resin is, for example, a liquid crystal polymer. The thermoplastic resin is not limited to liquid crystal polymers; for example, it may also be PTFE (polytetrafluoroethylene). In this embodiment, the first insulating layer 11 and the second insulating layer 12 are self-adhesive, and there is no adhesive layer between the first insulating layer 11 and the second insulating layer 12. Furthermore, in this embodiment, the second insulating layer 12 and the third insulating layer 13 are self-adhesive, and there is no adhesive layer between the second insulating layer 12 and the third insulating layer 13. Furthermore, in this embodiment, the third insulating layer 13 and the fourth insulating layer 14 are self-adhesive, and there is no adhesive layer between the third insulating layer 13 and the fourth insulating layer 14.

[0062] The thickness of each of the multiple insulating layers 11, 12, 13, and 14 is, for example, more than 10 μm and less than 120 μm.

[0063] In this embodiment, when viewed from above in the thickness direction D1 of the laminated substrate 1, the laminated substrate 1 is, for example, L-shaped. Figure 1 In the example, the laminated substrate 1 has a first portion 10a of a rectangular shape whose length along the X-axis direction is longer than its length along the Y-axis direction, and a second portion 10b of a strip shape whose length along the Y-axis direction is longer than its length along the X-axis direction.

[0064] (1.2) AC signal lines

[0065] like Figure 1 As shown, an AC signal line 2 is formed on the laminated substrate 1. The AC signal line 2 is a signal transmission line. In this disclosure, the AC signal line 2 is a line that transmits a signal whose magnitude changes over time. The AC signal line 2 is, for example, an NFC (near field communication) signal line. In this embodiment, the signal transmitted on the AC signal line 2 is an AC signal with a frequency of 13.56 MHz. The AC signal line 2 is not limited to an NFC signal line; it can also be a digital signal line or a differential line.

[0066] like Figure 2 as well as Figure 3As shown, the AC signal line 2 has multiple signal lines (signal electrodes) 21, 22, 23, and 24 that are separated from each other in the thickness direction D1 of the laminated substrate 1. Viewed from above in the thickness direction D1 of the laminated substrate 1, the multiple signal lines 21, 22, 23, and 24 overlap each other. Hereinafter, for ease of explanation, signal lines 21, 22, 23, and 24 will sometimes be referred to as the first signal line 21, the second signal line 22, the third signal line 23, and the fourth signal line 24, respectively.

[0067] Signal lines 21, 22, 23, and 24 have line widths W21, W22, W23, and W24, respectively.

[0068] Each of the signal lines 21 to 24 is conductive. The material of each of the signal lines 21 to 24 may include, for example, copper.

[0069] The thickness of each of the multiple signal lines 21 to 24 is, for example, 3 μm or more and 40 μm or less. The thickness of each of the multiple signal lines 21 to 24 is thinner than the thickness of each of the multiple insulating layers 11 to 14.

[0070] The first signal line 21 is stacked on the first insulating layer 11. Furthermore, the second signal line 22 is stacked on the second insulating layer 12. Furthermore, the third signal line 23 is stacked on the third insulating layer 13. Furthermore, the fourth signal line 24 is stacked on the fourth insulating layer 14. In the multilayer substrate 100, the first signal line 21, the first insulating layer 11, the second insulating layer 12, the second signal line 22, the third insulating layer 13, the third signal line 23, the fourth insulating layer 14, and the fourth signal line 24 are stacked in the following order: first signal line 21, first insulating layer 11, second insulating layer 12, second signal line 22, third insulating layer 13, third signal line 23, fourth insulating layer 14, and fourth signal line 24.

[0071] Each of the multiple signal lines 21 to 24 is formed with a given pattern. In this embodiment, when viewed from above in the thickness direction D1 of the laminated substrate 1, each of the multiple signal lines 21 to 24 is L-shaped. The first signal line 21 is formed, for example, by patterning a copper foil (hereinafter also referred to as the first copper foil) adhered to the first insulating layer 11. The second signal line 22 is formed, for example, by patterning a copper foil (hereinafter also referred to as the second copper foil) adhered to the second insulating layer 12. The third signal line 23 is formed, for example, by patterning a copper foil (hereinafter also referred to as the third copper foil) adhered to the third insulating layer 13. The fourth signal line 24 is formed, for example, by patterning a copper foil (hereinafter also referred to as the fourth copper foil) adhered to the fourth insulating layer 14.

[0072] Furthermore, the AC signal line 2 has multiple connecting conductors that electrically connect multiple signal lines 21 to 24. Each of the multiple connecting conductors is an interlayer connecting conductor that connects signal lines formed in two different insulating layers 11 to 14. Each of the multiple connecting conductors is conductive. In the AC signal line 2, the multiple signal lines 21 to 24 are electrically connected by multiple connecting conductors that penetrate one of the multiple insulating layers 11 to 14 in the thickness direction D1 of the laminated substrate 1. The multiple connecting conductors include multiple first connecting conductors 31 penetrating the first insulating layer 11, multiple second connecting conductors 32 penetrating the second insulating layer 12, multiple third connecting conductors 33 penetrating the third insulating layer 13, and multiple fourth connecting conductors 34 penetrating the fourth insulating layer 14. In this embodiment, the multiple first connecting conductors 31 and the multiple second connecting conductors 32 correspond one-to-one, and the corresponding first connecting conductors 31 and second connecting conductors 32 overlap and are electrically connected in the thickness direction D1 of the laminated substrate 1.

[0073] In this embodiment, a plurality of first connecting conductors 31 overlap with the first signal line 21 in the thickness direction D1 of the laminated substrate 1. The plurality of first connecting conductors 31 are separately arranged in the length direction of the first signal line 21. The length direction of the first signal line 21 is along the direction of the first signal line 21, orthogonal to the width direction (line width direction) of the first signal line 21, and is the direction in which signals are transmitted in the first signal line 21. Furthermore, a plurality of second connecting conductors 32 overlap with the second signal line 22 in the thickness direction D1 of the laminated substrate 1. The plurality of second connecting conductors 32 are separately arranged in the length direction of the second signal line 22. The length direction of the second signal line 22 is along the direction of the second signal line 22, orthogonal to the width direction (line width direction) of the second signal line 22, and is the direction in which signals are transmitted in the second signal line 22. In this embodiment, the first signal line 21 and the second signal line 22 are electrically connected by the plurality of first connecting conductors 31 and the plurality of second connecting conductors 32.

[0074] Furthermore, a plurality of third connecting conductors 33 overlap with the third signal line 23 in the thickness direction D1 of the laminated substrate 1. The plurality of third connecting conductors 33 are separately arranged in the length direction of the third signal line 23. The length direction of the third signal line 23 is the direction along the third signal line 23, orthogonal to the width direction (line width direction) of the third signal line 23, and is the direction in which signals are transmitted in the third signal line 23. In this embodiment, the second signal line 22 and the third signal line 23 are electrically connected by the plurality of third connecting conductors 33.

[0075] Furthermore, a plurality of fourth connecting conductors 34 overlap with the fourth signal line 24 in the thickness direction D1 of the laminated substrate 1. The plurality of fourth connecting conductors 34 are separately arranged in the length direction of the fourth signal line 24. The length direction of the fourth signal line 24 is the direction along which the fourth signal line 24 is located, is orthogonal to the width direction (line width direction) of the fourth signal line 24, and is the direction in which signals are transmitted in the fourth signal line 24. In this embodiment, the third signal line 23 and the fourth signal line 24 are electrically connected through the plurality of fourth connecting conductors 34.

[0076] Each of the plurality of first connecting conductors 31, the plurality of second connecting conductors 32, the plurality of third connecting conductors 33, and the plurality of fourth connecting conductors 34 is conductive. Each of the plurality of first connecting conductors 31, the plurality of second connecting conductors 32, the plurality of third connecting conductors 33, and the plurality of fourth connecting conductors 34 comprises, for example, copper, a copper-tin alloy, and resin. The plurality of first connecting conductors 31 are formed, for example, by filling the plurality of through-holes formed in the first insulating layer 11 with a portion of the first copper foil, filling the plurality of through-holes with a conductive paste comprising copper, a low-melting-point metal (e.g., tin), and resin, and then heating. The plurality of second connecting conductors 32 are formed, for example, by filling the plurality of through-holes formed in the second insulating layer 12 with a portion of the second copper foil, filling the plurality of through-holes with a conductive paste comprising copper, a low-melting-point metal (e.g., tin), and resin, and then heating. The plurality of third connecting conductors 33 are formed, for example, by filling the plurality of through holes formed in the third insulating layer 13 with a portion of the third copper foil, filling the plurality of through holes with a conductive paste comprising copper, a low-melting-point metal (e.g., tin), and resin, and then heating. The plurality of fourth connecting conductors 34 are formed, for example, by filling the plurality of through holes formed in the fourth insulating layer 14 with a portion of the fourth copper foil, filling the plurality of through holes with a conductive paste comprising copper, a low-melting-point metal (e.g., tin), and resin, and then heating.

[0077] (1.3) Grounding electrode

[0078] Multiple grounding electrodes 41-44 are formed on the laminated substrate 1. For example... Figure 2 as well as Figure 3As shown, multiple ground electrodes 41 to 44 are separated from each other in the thickness direction D1 of the laminated substrate 1. Viewed from the thickness direction D1 of the laminated substrate 1, the multiple ground electrodes 41 to 44 overlap each other. The multiple ground electrodes 41 to 44 are adjacent to the multiple signal lines 21 to 24 in the width direction of the multiple signal lines 21 to 24. The phrase "multiple ground electrodes 41 to 44 are adjacent to the multiple signal lines 21 to 24 in the width direction of the multiple signal lines 21 to 24" means that no other conductor is disposed between the signal lines 21 to 24 and the ground electrodes 41 to 44 in the width direction of the signal lines 21 to 24, and the signal lines 21 to 24 and the ground electrodes 41 to 44 are disposed separately. Hereinafter, for ease of explanation, ground electrodes 41, 42, 43, and 44 will sometimes be referred to as the first ground electrode 41, the second ground electrode 42, the third ground electrode 43, and the fourth ground electrode 44, respectively.

[0079] In this embodiment, the first ground electrode 41, the second ground electrode 42, the third ground electrode 43 and the fourth ground electrode 44 are respectively adjacent to the first signal line 21, the second signal line 22, the third signal line 23 and the fourth signal line 24 in the width direction of the first signal line 21, the second signal line 22, the third signal line 23 and the fourth signal line 24.

[0080] Each of the multiple grounding electrodes 41 to 44 is conductive. The material of each of the multiple grounding electrodes 44 includes, for example, copper.

[0081] The thickness of each of the multiple grounding electrodes 41 to 44 is, for example, more than 3 μm and less than 40 μm.

[0082] The first ground electrode 41 is stacked on the first insulating layer 11. Furthermore, the second ground electrode 42 is stacked on the second insulating layer 12. Furthermore, the third ground electrode 43 is stacked on the third insulating layer 13. Furthermore, the fourth ground electrode 44 is stacked on the fourth insulating layer 14. In the multilayer substrate 100, the first ground electrode 41, the first insulating layer 11, the second insulating layer 12, the second ground electrode 42, the third insulating layer 13, the third ground electrode 43, the fourth insulating layer 14, and the fourth ground electrode 44 are stacked in the following order: first ground electrode 41, first insulating layer 11, second insulating layer 12, second ground electrode 42, third insulating layer 13, third ground electrode 43, fourth insulating layer 14, and fourth ground electrode 44.

[0083] Multiple ground electrodes 41-44 are each formed in a given pattern. In this embodiment, when viewed from above in the thickness direction D1 of the laminated substrate 1, each of the multiple ground electrodes 41-44 is L-shaped. The first ground electrode 41 is formed, for example, by patterning a first copper foil adhered to the first insulating layer 11. The second ground electrode 42 is formed, for example, by patterning a second copper foil adhered to the second insulating layer 12. The third ground electrode 43 is formed, for example, by patterning a third copper foil adhered to the third insulating layer 13. The fourth ground electrode 44 is formed, for example, by patterning a fourth copper foil adhered to the fourth insulating layer 14.

[0084] In this embodiment, multiple ground electrodes 41-44 are electrically connected by multiple connecting conductors that penetrate one of the multiple insulating layers 11-14 in the thickness direction D1 of the laminated substrate 1. The multiple connecting conductors include multiple fifth connecting conductors 51 penetrating the first insulating layer 11, multiple sixth connecting conductors 52 penetrating the second insulating layer 12, multiple seventh connecting conductors 53 penetrating the third insulating layer 13, and multiple eighth connecting conductors 54 penetrating the fourth insulating layer 14. In this embodiment, the multiple fifth connecting conductors 51 and the multiple sixth connecting conductors 52 correspond one-to-one, and the corresponding fifth connecting conductors 51 and sixth connecting conductors 52 overlap and are electrically connected in the thickness direction D1 of the laminated substrate 1.

[0085] In this embodiment, a plurality of fifth connecting conductors 51 overlap with the first ground electrode 41 in the thickness direction D1 of the laminated substrate 1. The plurality of fifth connecting conductors 51 are separately arranged in the length direction of the first ground electrode 41. The length direction of the first ground electrode 41 is along the length direction of the first signal line 21. Furthermore, a plurality of sixth connecting conductors 52 overlap with the second ground electrode 42 in the thickness direction D1 of the laminated substrate 1. The plurality of sixth connecting conductors 52 are separately arranged in the length direction of the second ground electrode 42. The length direction of the second ground electrode 42 is along the length direction of the second signal line 22. In this embodiment, the first ground electrode 41 and the second ground electrode 42 are electrically connected by the plurality of fifth connecting conductors 51 and the plurality of sixth connecting conductors 52.

[0086] Furthermore, a plurality of seventh connecting conductors 53 overlap with the third ground electrode 43 in the thickness direction D1 of the laminated substrate 1. The plurality of seventh connecting conductors 53 are separately arranged in the length direction of the third ground electrode 43. The length direction of the third ground electrode 43 is along the length direction of the third signal line 23. In this embodiment, the second ground electrode 42 and the third ground electrode 43 are electrically connected by the plurality of seventh connecting conductors 53.

[0087] Furthermore, a plurality of eighth connecting conductors 54 overlap with the fourth ground electrode 44 in the thickness direction D1 of the laminated substrate 1. The plurality of eighth connecting conductors 54 are separately arranged in the length direction of the fourth ground electrode 44. The length direction of the fourth ground electrode 44 is along the direction of the fourth signal line 24. In this embodiment, the third ground electrode 43 and the fourth ground electrode 44 are electrically connected by the plurality of eighth connecting conductors 54.

[0088] Each of the plurality of fifth connecting conductors 51, the plurality of sixth connecting conductors 52, the plurality of seventh connecting conductors 53, and the plurality of eighth connecting conductors 54 is conductive. Each of the plurality of fifth connecting conductors 51, the plurality of sixth connecting conductors 52, the plurality of seventh connecting conductors 53, and the plurality of eighth connecting conductors 54 comprises, for example, copper, a copper-tin alloy, and resin. The plurality of fifth connecting conductors 51 are formed, for example, by filling the plurality of through-holes formed in the first insulating layer 11 with a portion of the first copper foil, filling the plurality of through-holes with a conductive paste comprising copper, a low-melting-point metal (e.g., tin), and resin, and then heating. The plurality of sixth connecting conductors 52 are formed, for example, by filling the plurality of through-holes formed in the second insulating layer 12 with a conductive paste comprising copper, a low-melting-point metal (e.g., tin), and resin, and then heating, while the plurality of through-holes formed in the second insulating layer 12 are a portion of the second copper foil. The plurality of seventh connecting conductors 53 are formed, for example, by filling the plurality of through holes formed in the third insulating layer 13 with a portion of the third copper foil, filling the plurality of through holes with a conductive paste comprising copper, a low-melting-point metal (e.g., tin), and resin, and then heating. The plurality of eighth connecting conductors 54 are formed, for example, by filling the plurality of through holes formed in the fourth insulating layer 14 with a conductive paste comprising copper, a low-melting-point metal (e.g., tin), and resin, and then heating, while the plurality of through holes formed in the fourth insulating layer 14 are a portion of the fourth copper foil.

[0089] (2) Layout

[0090] The transmission line region of the multilayer substrate 100 includes a first transmission line region 101 and a second transmission line region 102. Viewed from the thickness direction D1 of the multilayer substrate 1, the first transmission line region 101 is the region with the smallest maximum linewidth among the plurality of signal lines 21 to 24, and the second transmission line region 102 is the region with the largest maximum linewidth among the plurality of signal lines 21 to 24. The maximum linewidth among the plurality of signal lines 21 to 24 is the maximum value among the linewidths W21 of the first signal line 21, W22 of the second signal line 22, W23 of the third signal line 23, and W24 of the fourth signal line 24, viewed from the thickness direction D1 of the multilayer substrate 1. In the multilayer substrate 100 of this embodiment, the outer width W1 in the width direction of the plurality of signal lines 21 to 24 in the first transmission line region 101 (refer to...) Figure 1 The width W2 of the plurality of signal lines 21-24 in the second transmission line area 102 in the width direction (refer to) Figure 1 They are different. More specifically, the outer width W2 is wider than the outer width W1.

[0091] In the first transmission line region 101 of this embodiment, as Figure 2 As shown, the line widths W21 of the first signal line 21, W22 of the second signal line 22, W23 of the third signal line 23, and W24 of the fourth signal line 24 are the same. Therefore, in the second transmission line region 102, the maximum line width of the plurality of signal lines 21 to 24 can be defined using any one of the line widths W21 to W24. In the first transmission line region 101, from the viewpoint of increasing the cross-sectional area of ​​the AC signal line 2, it is preferable that the line widths W21 to W24 are the same and that they are wider, but the line widths W21 to W24 can also be different. The term "cross-sectional area of ​​the AC signal line 2" refers to the sum of the cross-sectional areas of the plurality of signal lines 21 to 24 in any cross-section orthogonal to the length direction of the AC signal line 2.

[0092] In the first transmission line region 101 of this embodiment, as Figure 2 As shown, the electrode widths W41 to W44 of the multiple grounding electrodes 41 to 44 are the same, but they can also be different from each other.

[0093] Furthermore, in the second transmission line region 102 of this embodiment, such as Figure 3As shown, the line widths W22 of the second signal line 22, W23 of the third signal line 23, and W24 of the fourth signal line 24 are the same, while the line width W21 of the first signal line 21 is the smallest. Therefore, in the second transmission line region 102, the maximum line width of the plurality of signal lines 21 to 24 can be defined using any of the line widths W22 to W24. In the second transmission line region 102, from the viewpoint of increasing the cross-sectional area of ​​the AC signal line 2, it is preferable that the line widths W22 to W24 are the same and that they are wider, but the line widths W22 to W24 can also be different.

[0094] In the second transmission line region 102 of this embodiment, such as Figure 3 As shown, the electrode width W41 of one of the four grounding electrodes 41-44 is wider than the electrode widths W42-W44 of each of the other three grounding electrodes 42-44. In the second transmission line region 102 of this embodiment, the electrode widths W42-W44 of three of the four grounding electrodes 41-44 are the same, but the electrode widths W42-W44 of the three grounding electrodes 42-44 can also be different.

[0095] In the first transmission line region 101 of this embodiment, as Figure 2 As shown, in the thickness direction D1 of the laminated substrate 1, none of the multiple signal lines 21-24 overlap with any of the multiple ground electrodes 41-44. In the second transmission line region 102 of this embodiment, as... Figure 3 As shown, one of the multiple ground electrodes 41 to 44, ground electrode 41 (first ground electrode 41), and signal lines 22 to 24, other than signal line 21 which is adjacent to ground electrode 41 in the width direction, overlap in the thickness direction D1.

[0096] In the second transmission line region 102 of this embodiment, such as Figure 3As shown, among the multiple signal lines 21 to 24, in signal line 22 adjacent to ground electrode 41 in the thickness direction D1 of the laminated substrate 1, more than half of the region in the width direction overlaps with ground electrode 41 in the thickness direction D1. "Adjacent to ground electrode 41 and signal line 22 in the thickness direction D1" means that ground electrode 41 and signal line 22 are separated in the thickness direction D1, and there is no other conductor between ground electrode 41 and signal line 22 in the thickness direction D1. The width H1 of the region of signal line 22 overlapping with ground electrode 41 in the thickness direction D1 of the laminated substrate 1, in the width direction, is, for example, half the line width W22. The width H1 may also be less than half the line width W22, but from the viewpoint of improving the current distribution in the width direction of each of the signal lines 22 to 24, it is preferable to be more than half the line width W22.

[0097] (3) Characteristics of multilayer substrates

[0098] In the multilayer substrate 100 of this embodiment, compared with the case where the ground electrode does not overlap with the signal line in the second transmission line region, the AC resistance of the AC signal line 2 can be reduced. The mechanism by which the AC resistance can be reduced will be explained below.

[0099] In a transmission line with the same layout as the first transmission line area 101, if the maximum line width of the four signal lines 21 to 24 is set to the signal line width and the signal line width is varied, such as Figure 5 As shown in characteristic A1, the AC resistance decreases as the signal line width increases. Furthermore, in a transmission line with the same layout as the second transmission line region 102, if the ground electrode 41 overlaps with the three signal lines 22-24, the maximum line width of the signal lines 22-24 is set to the signal line width, and the signal line width is varied, as... Figure 5 As shown in characteristic B1, the AC resistance decreases as the signal line width increases.

[0100] according to Figure 5 It can be seen that in both characteristic A1 and characteristic B1, the AC resistance decreases as the signal line width increases, but characteristic A1 and characteristic B1 overlap. Furthermore, according to... Figure 5 It can be seen that, with a signal line width narrower than the signal line width at the intersection of characteristics A1 and B1, characteristic A1 has a smaller AC resistance. Furthermore, according to... Figure 5 It can be seen that, with a signal line width wider than that at the intersection, characteristic B1 has a smaller AC resistance than characteristic A1.

[0101] If considered Figure 5Characteristics A1 and B1 allow for a further reduction in AC resistance when the signal line width is narrow. By adopting the same layout as the first transmission line region 101, the cross-sectional area of ​​the AC signal line 2 can be increased. However, if the same layout as the first transmission line region 101 is adopted, when the signal line width is wide, the current density at the center of each of the signal lines 21-24 is smaller compared to the current density at each of the two ends in the width direction, resulting in a decrease in the reduction effect on AC resistance. In contrast, when the signal line width is wide, even if the ground electrode 41 is arranged to overlap with the signal lines 22-24 in the thickness direction D1 of the laminated substrate 1, the cross-sectional area of ​​the AC signal line 2 can be ensured. Therefore, by overlapping the ground electrode 41 with the signal lines 22-24 in the thickness direction D1 of the laminated substrate 1, the difference between the current density at each end of the signal lines 22-24 in the width direction and the current density at the center can be reduced, further reducing AC resistance.

[0102] (4) Manufacturing method of multilayer substrate

[0103] In the manufacturing method of the multilayer substrate 100 of this embodiment, for example, a first insulating layer 11 on which a first signal line 21 and a first ground electrode 41 are formed, a second insulating layer 12 on which a second signal line 22 and a second ground electrode 42 are formed, a third insulating layer 13 on which a third signal line 23 and a third ground electrode 43 are formed, and a fourth insulating layer 14 on which a fourth signal line 24 and a fourth ground electrode 44 are formed are stacked on a metal plate (not shown), and the multilayer substrate 100 is formed by pressing from above while heating.

[0104] (5) Effects

[0105] In the multilayer substrate 100 according to Embodiment 1, multiple ground electrodes 41-44 are separated from each other in the thickness direction D1 of the multilayer substrate 1 and are adjacent to multiple signal lines 21-24 in the width direction. In the first transmission line region 101 where the maximum line width of the multiple signal lines 21-24 is the smallest, the multiple signal lines 21-24 do not overlap with any of the multiple ground electrodes 41-44 in the thickness direction D1 of the multilayer substrate 1. In the second transmission line region 102 where the maximum line width of the multiple signal lines 21-24 is the largest, one of the multiple ground electrodes 41-44, a ground electrode 41, overlaps with signal lines 22-24 other than the signal line 21 adjacent to the ground electrode 41.

[0106] Based on the above structure, the AC resistance of the multilayer substrate 100 can be reduced. More specifically, regarding the multilayer substrate 100 according to Embodiment 1, in the first transmission line region 101 where the maximum line width of the plurality of signal lines 21 to 24 is the smallest, in the thickness direction D1 of the stacked substrate 1, the plurality of signal lines 21 to 24 do not overlap with any of the plurality of ground electrodes 41 to 44, thus the cross-sectional area of ​​the AC signal lines 2 can be further increased, and the AC resistance can be reduced. Furthermore, regarding the multilayer substrate 100 according to Embodiment 1, in the second transmission line region 102 where the maximum line width of the plurality of signal lines 21 to 24 is the largest, one of the ground electrodes 41 among the plurality of ground electrodes 41 to 44 overlaps with signal lines 22 to 24 other than the signal line 21 adjacent to the ground electrode 41 among the plurality of signal lines 21 to 24, thus the imbalance of current density in the width direction of the plurality of signal lines 21 to 24 can be reduced, and the AC resistance can be further reduced.

[0107] Furthermore, in the second transmission line region 102 of the multilayer substrate 100 according to Embodiment 1, among the plurality of signal lines 21 to 24, more than half of the region in the width direction of the signal line 22 adjacent to a ground electrode 41 in the thickness direction D1 overlaps with a ground electrode 41 in the thickness direction D1.

[0108] According to the above structure, compared with the case where less than half of the area of ​​the signal line 22 in the width direction of the thickness direction D1 of the laminated substrate 1 overlaps with a ground electrode 41, the current distribution in the width direction of the signal lines 22-24 can be improved, the imbalance of current density can be further reduced, and thus the AC resistance can be further reduced.

[0109] Furthermore, in the multilayer substrate 100 according to Embodiment 1, the outline width W2 of the plurality of signal lines 21 to 24 in the second transmission line region 102 in the width direction is wider than the outline width W1 of the plurality of signal lines 21 to 24 in the width direction in the first transmission line region 101.

[0110] Based on the above structure, the AC resistance in the first transmission line region 101 and the second transmission line region 102 can be further reduced for AC signal line 2.

[0111] (Implementation Method 2)

[0112] Reference Figures 6-8 The multilayer substrate 100A according to Embodiment 2 will be described. Regarding the multilayer substrate 100A according to Embodiment 2, compared with the multilayer substrate 100 according to Embodiment 1 (see...), Figures 1-4 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figures 6-8 In each of the figures, with Figures 1-4 Similarly, orthogonal coordinates with three mutually orthogonal axes—X, Y, and Z—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 7 The axis of ) is marked as the Z-axis.

[0113] (1) Structure

[0114] In the multilayer substrate 100A according to Embodiment 2, such as Figure 8 As shown, the difference from the multilayer substrate 100 of Embodiment 1 is that, among the four ground electrodes 41 to 44, it is not the first ground electrode 41 but the second ground electrode 42 that overlaps with the signal lines 21, 23, and 24 in the thickness direction D1 of the multilayer substrate 1.

[0115] Furthermore, in the second transmission line region 102 of this embodiment, such as Figure 8 As shown, the line widths W21 of the first signal line 21, W23 of the third signal line 23, and W24 of the fourth signal line 24 are the same, while the line width W22 of the second signal line 22 is the smallest. Therefore, in the second transmission line region 102, the maximum line width of the multiple signal lines 21 to 24 can be defined using any one of the line widths W21, W23, and W24. In the second transmission line region 102, from the viewpoint of increasing the cross-sectional area of ​​the AC signal line 2, it is preferable that the line widths W21, W23, and W24 are the same and that they are wider, but the line widths W21, W23, and W24 can also be different.

[0116] In the second transmission line region 102 of this embodiment, such as Figure 8 As shown, the electrode width W42 of one of the four grounding electrodes 41 to 44, grounding electrode 42, is wider than the electrode widths W41, W43, and W44 of the other three grounding electrodes 41, 43, and 44. In the second transmission line region 102 of this embodiment, the electrode widths W41, W43, and W44 of three of the four grounding electrodes 41 to 44 are the same, but the electrode widths W41, W43, and W44 of the three grounding electrodes 41, 43, and 44 can also be different.

[0117] In the first transmission line region 101 of this embodiment, as Figure 7 As shown, in the thickness direction D1 of the laminated substrate 1, none of the multiple signal lines 21 to 24 overlap with any of the multiple ground electrodes 41 to 44. In the second transmission line region 102 of this embodiment, as... Figure 8As shown, one of the multiple ground electrodes 41 to 44, ground electrode 42 (second ground electrode 42), and signal lines 21, 23, and 24, other than signal line 22 which is adjacent to ground electrode 42 in the width direction, overlap in the thickness direction D1.

[0118] In the second transmission line region 102 of this embodiment, among the plurality of signal lines 21 to 24, the signal line 21 adjacent to the ground electrode 42 in the thickness direction D1 has a region in the width direction that overlaps with the ground electrode 42 in the thickness direction D1. In the signal line 23 adjacent to the ground electrode 42 in the thickness direction D1, the width H1 of the region overlapping with the ground electrode 42 is, for example, half the line width W23. The width H1 may also be less than half the line width W23, but from the viewpoint of improving the current distribution in the width direction of each of the signal lines 21, 23, and 24, it is preferable to be at least half the line width W23. In the signal line 21 adjacent to the ground electrode 42 in the thickness direction D1, the width H2 of the region overlapping with the ground electrode 42 is, for example, half the line width W21. The width H2 can also be less than half the line width W21, but from the viewpoint of improving the current distribution in the width direction of each of the signal lines 21, 23, and 24, it is preferable to be more than half the line width W21.

[0119] (2) Effect

[0120] Similar to the multilayer substrate 100 of Embodiment 1, the multilayer substrate 100A according to Embodiment 2 can reduce the AC resistance of the multilayer substrate 100. More specifically, regarding the multilayer substrate 100A according to Embodiment 2, in the first transmission line region 101, the plurality of signal lines 21 to 24 on the thickness direction D1 of the stacked substrate 1 do not overlap with any of the plurality of ground electrodes 41 to 44, thus further increasing the cross-sectional area of ​​the AC signal lines 2 and reducing the AC resistance. Furthermore, regarding the multilayer substrate 100A according to Embodiment 2, in the second transmission line region 102, one of the ground electrodes 42 among the plurality of ground electrodes 41 to 44 overlaps with signal lines 21, 23, and 24 other than the signal line 22 adjacent to the ground electrode 42 among the plurality of signal lines 21 to 24, thus reducing the imbalance of current density in the width direction of the plurality of signal lines 21 to 24 and further reducing the AC resistance.

[0121] (Implementation Method 3)

[0122] Reference Figures 9-11The multilayer substrate 100B according to Embodiment 3 will be described. Regarding the multilayer substrate 100B according to Embodiment 3, compared with the multilayer substrate 100 according to Embodiment 1 (see...), Figures 1-4 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figures 9-11 In, with Figures 1-4 Similarly, orthogonal coordinates with three mutually orthogonal axes—X, Y, and Z—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 10 The axis of ) is marked as the Z-axis.

[0123] (1) Structure

[0124] In the second transmission line region 102 of the multilayer substrate 100B according to Embodiment 3, such as Figure 11 As shown, the entire region of the signal line 22 adjacent to the ground electrode 41 in the thickness direction D1 of the laminated substrate 1 overlaps with the ground electrode 41 in the thickness direction D1. The electrode width W41 of the ground electrode 41 in the width direction of the signal line 22 is the total length of the line width W22 of the signal line 22, the electrode width W42 of the ground electrode 42, and the distance L2 between the signal line 22 and the ground electrode 42. The ground electrode 41 can be any length that overlaps with the entire region of the signal line 22 and the fifth connecting conductor 51, or it can be shorter than the total length mentioned above.

[0125] (2) Effect

[0126] The multilayer substrate 100B according to Embodiment 3 is similar to the multilayer substrate 100 according to Embodiment 1 in that it can reduce the AC resistance of the multilayer substrate 100.

[0127] Furthermore, in the second transmission line region 102 of the multilayer substrate 100B according to Embodiment 3, among the plurality of signal lines 21 to 24, the entire region of the signal line 22 adjacent to a ground electrode 41 in the thickness direction D1 overlaps with a ground electrode 41 in the thickness direction D1.

[0128] The above structure can improve noise resistance.

[0129] (Implementation Method 4)

[0130] Reference Figures 12-14 The multilayer substrate 100C according to Embodiment 4 will be described. Regarding the multilayer substrate 100C according to Embodiment 4, compared with the multilayer substrate 100 according to Embodiment 1 (see...), Figures 1-4 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figures 12-14 In each of the figures, with Figures 1-4Similarly, orthogonal coordinates with three mutually orthogonal axes—X, Y, and Z—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 13 The axis of ) is marked as the Z-axis.

[0131] (1) Structure

[0132] In the multilayer substrate 100C according to embodiment 4, such as Figure 12 As shown, when viewed from the thickness direction D1 of the laminated substrate 1, the laminated substrate 1 is a long strip shape in the Y-axis direction, which is longer than its length in the X-axis direction.

[0133] In the multilayer substrate 100C, multiple signal lines 21 to 24 in the first transmission line region 101 (refer to...) Figure 13 The external width W1 in the width direction and the multiple signal lines 21 to 24 in the second transmission line area 102 (refer to) Figure 14 The outer width W2 of the ) is the same in the width direction.

[0134] In this embodiment, the transmission line region of the multilayer substrate 100C includes a first transmission line region 101, a second transmission line region 102, and a third transmission line region 103 located in the second transmission line region 102 on the side opposite to the first transmission line region 101. Furthermore, the transmission line region of the multilayer substrate 100C also includes a fourth transmission line region 104 located between the first transmission line region 101 and the second transmission line region 102. Therefore, in the multilayer substrate 100C, the first transmission line region 101, the fourth transmission line region 104, the second transmission line region 102, and the third transmission line region 103 are arranged in the order of first transmission line region 101, fourth transmission line region 104, second transmission line region 102, and third transmission line region 103. In the multilayer substrate 100C, the outer width W1 of the first transmission line region 101, the outer width W4 of the fourth transmission line region 104, the outer width W2 of the second transmission line region 102, and the outer width W3 of the third transmission line region 103 are the same.

[0135] exist Figure 12 In the diagram, the boundary BL14 between the first transmission line region 101 and the fourth transmission line region 104 is illustrated using a dashed line. Furthermore, in... Figure 12 In the diagram, the boundary BL24 between the fourth transmission line region 104 and the second transmission line region 102 is illustrated using a dashed line. Furthermore, in... Figure 12 In the diagram, the boundary BL23 of the second transmission line region 102 and the third transmission line region 103 is illustrated with a single-dotted line. The boundaries BL14, BL23, and BL24 are imaginary boundaries illustrated for illustrative purposes.

[0136] In Figure 12 , the maximum line width in the first transmission line region 101 (the line widths W21 to W24 of the signal lines 21 to 24 in the example of Figure 13 ) is illustrated as X1. Further, in Figure 12 , the maximum line width in the second transmission line region 102 (the line widths W22 to W24 of the signal lines 22 to 24 in the example of Figure 14 ) is illustrated as X2. Further, in Figure 12 , the maximum line width in the third transmission line region 103 is illustrated as X3. In the multilayer substrate 100C, X1 in the first transmission line region 101 is fixed in the length direction of the first transmission line region 101, X2 in the second transmission line region 102 is fixed in the length direction of the second transmission line region 102, and X3 in the third transmission line region 103 is fixed in the length direction of the third transmission line region 103. Further, in the multilayer substrate 100C, X1 < X3 < X2. Further, in the multilayer substrate 100C, the maximum line width in the fourth transmission line region 104 becomes wider as it moves away from the first transmission line region 101 and closer to the second transmission line region 102.

[0137] In the present embodiment, the electrode width W44 of the ground electrode 44 in the first transmission line region 101 is wider than the electrode width W44 of the ground electrode 44 in the third transmission line region 103, and the electrode width W44 of the ground electrode 44 in the third transmission line region 103 is wider than the electrode width W44 of the ground electrode 44 in the second transmission line region 102.

[0138] The third transmission line region 103 of the present embodiment satisfies the condition of X3 ≤ (X1 + X2) / 2, and, similar to the first transmission line region 101 (refer to Figure 13 ), in the thickness direction D1 of the stacked substrate 1, none of the plurality of signal lines 21 to 24 overlap with any of the plurality of ground electrodes 41 to 44.

[0139] Regarding the third transmission line region 103, in the case where the condition of X3 > (X1 + X2) / 2 is satisfied, similar to the second transmission line region 102, one ground electrode 41 among the plurality of ground electrodes 41 to 44 and the signal lines 22 to 24 other than the signal line 21 adjacent to the one ground electrode 41 among the plurality of signal lines 21 to 24 overlap.

[0140] In this embodiment, the maximum line width in the fourth transmission line region 104 is wider than (X1+X2) / 2. Similarly to the second transmission line region 102, one of the plurality of ground electrodes 41 to 44, ground electrode 41, overlaps with signal lines 22 to 24, excluding signal line 21 adjacent to ground electrode 41.

[0141] (2) Effect

[0142] The multilayer substrate 100C according to Embodiment 4, like the multilayer substrate 100 according to Embodiment 1, can achieve a reduction in AC resistance.

[0143] Furthermore, in the multilayer substrate 100C according to Embodiment 4, when the maximum line width in the first transmission line region 101 is set to X1 and the maximum line width in the second transmission line region 102 is set to X2, in the third transmission line region 103 where the maximum line width among the plurality of signal lines 21 to 24 is greater than X1 and less than (X1+X2) / 2, in the thickness direction D1, the plurality of signal lines 21 to 24 do not overlap with any of the plurality of ground electrodes 41 to 44.

[0144] According to the above structure, when the AC signal line 2 is formed by crossing the first transmission line region 101, the second transmission line region 102 and the third transmission line region 103, it is possible to reduce the AC resistance.

[0145] (Implementation Method 5)

[0146] Reference Figures 15-17 The multilayer substrate 100D according to Embodiment 5 will be described. Regarding the multilayer substrate 100D according to Embodiment 5, compared with the multilayer substrate 100C according to Embodiment 4 (see...), Figures 12-14 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figures 15-17 In each of the figures, with Figures 12-14 Similarly, orthogonal coordinates with three mutually orthogonal axes—X, Y, and Z—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 16 The axis of ) is marked as the Z-axis.

[0147] (1) Structure

[0148] In the multilayer substrate 100D according to embodiment 5, such as Figure 15 As shown, the outer width W2 of the second transmission line region 102 is wider than the outer width W3 of the third transmission line region 103, and the outer width W3 of the third transmission line region 103 is wider than the outer width W1 of the first transmission line region 101.

[0149] In this embodiment, the electrode width W44 of the ground electrode 44 in the first transmission line region 101, the electrode width W44 of the ground electrode 44 in the third transmission line region 103, the electrode width W44 of the ground electrode 44 in the third transmission line region 103, and the electrode width W44 of the ground electrode 44 in the second transmission line region 102 are the same.

[0150] (2) Effect

[0151] The multilayer substrate 100D according to Embodiment 5, like the multilayer substrate 100C according to Embodiment 4, can achieve a reduction in AC resistance.

[0152] Furthermore, compared with the multilayer substrate 100C according to Embodiment 4, the multilayer substrate 100D according to Embodiment 5 can increase the area of ​​the plurality of ground electrodes 41 to 44, and can make the potential of the plurality of ground electrodes 41 to 44 more stable.

[0153] (Implementation Method 6)

[0154] Reference Figures 18-21 The multilayer substrate 100E according to Embodiment 6 will be described. Regarding the multilayer substrate 100E according to Embodiment 6, compared with the multilayer substrate 100C according to Embodiment 4 (see...), Figures 12-14 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figures 18-21 In each of the figures, with Figures 12-14 Similarly, orthogonal coordinates with three mutually orthogonal axes—X, Y, and Z—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 20 The axis of ) is marked as the Z-axis.

[0155] (1) Structure

[0156] In the multilayer substrate 100E according to embodiment 6, such as Figure 18 As shown, the outer width W1 of the first transmission line region 101, the outer width W2 of the second transmission line region 102, the outer width W3 of the third transmission line region 103E, and the outer width W4 of the fourth transmission line region 104 are the same.

[0157] In the multilayer substrate 100E according to Embodiment 6, the electrode width W44 of the ground electrode 44 in the first transmission line region 101 (refer to...) Figure 20 The electrode width W44 of the ground electrode 44 in the second transmission line region 102 (refer to) and the electrode width W44 of the ground electrode 44 in the second transmission line region 102 (refer to) Figure 21The same applies. Furthermore, in the multilayer substrate 100E, the width W101 of the portion of the plurality of ground electrodes 41 to 44 in the first transmission line region 101 opposite to the side of the plurality of signal lines 21 to 24 is wider than the width W102 of the portion of the plurality of ground electrodes 41 to 44 in the second transmission line region 102 opposite to the side of the plurality of signal lines 21 to 24.

[0158] In addition, such as Figures 19-21 As shown, the multilayer substrate 100E according to Embodiment 6 also includes an RF signal line 6. The RF signal line 6 is formed on the multilayer substrate 1. The RF signal line 6 is configured to span the first transmission line region 101, the second transmission line region 102, and the third transmission line region 103E. The frequency of the high-frequency signal transmitted on the RF signal line 6 is a higher frequency (e.g., 2.45 GHz) than the frequency of the signal transmitted on the AC signal line 2 (e.g., 13.56 MHz). The RF signal line 6 is designed, for example, to have an impedance of 50 Ω. Figure 20 as well as Figure 21 As shown, the RF signal line 6 is located between the first ground electrode 41 and the fourth ground electrode 44 in the thickness direction D1 of the multilayer substrate 1. Therefore, in the multilayer substrate 100E, the multilayer substrate 1, the RF signal line 6, the first ground electrode 41, and the fourth ground electrode 44 constitute a stripline. In this embodiment, the second ground electrode 42 is divided into two segmented ground electrodes 421 and 422 in the width direction of the signal line 22, and the third ground electrode 43 is divided into two segmented ground electrodes 431 and 432 in the width direction of the signal line 23. In this embodiment, the RF signal line 6 is disposed between the two segmented ground electrodes 421 and 422.

[0159] Furthermore, in the multilayer substrate 100E, the length directions of the first transmission line region 101 and the second transmission line region 102 are along the Y-axis, and the length direction of the third transmission line region 103E is along the X-axis. Therefore, in the multilayer substrate 100E, the length directions of the second transmission line region 102 and the third transmission line region 103E are orthogonal.

[0160] Multiple signal lines 21-24 are formed across the first transmission line region 101, the second transmission line region 102, and the third transmission line region 103E. The width directions of the multiple signal lines 21-24 in the first transmission line region 101 are orthogonal to the width directions of the multiple signal lines 21-24 in the third transmission line region 103E. The RF signal line 6 includes a first portion 61 formed in the first transmission line region 101, a second portion 62 formed in the second transmission line region 102, and a third portion 63 formed in the third transmission line region 103E.

[0161] In the multilayer substrate 100E, when viewed from the thickness direction D1 of the multilayer substrate 1, a recess 120 is formed at the end of the third transmission line region 103E side in the width direction (along the X-axis) of the first transmission line region 101, on the outer edge 107 of the multilayer substrate 1. The recess 120 is formed to facilitate bending of the multilayer substrate 100E in the first transmission line region 101. Viewed from the thickness direction D1 of the multilayer substrate 1, as... Figure 19 As shown, the first shortest distance L61 between the first portion 61 of the RF signal line 6 and the outer edge 107 of the laminated substrate 1 is longer than the second shortest distance L62 between the second portion 62 of the RF signal line 6 and the outer edge 107 of the laminated substrate 1, and is also longer than the third shortest distance L63 between the third portion 63 of the RF signal line 6 and the outer edge 107 of the laminated substrate 1. The first shortest distance L61 is set to a value greater than the depth of the recess 120, such that the first portion 61 of the RF signal line 6 and the recess 120 do not overlap in the direction in which the first transmission line region 101 and the second transmission line region 102 are arranged (the direction parallel to the Y-axis). Viewed from the thickness direction D1 of the laminated substrate 1, the connecting portion 613 of the first portion 61 and the third portion 63 in the RF signal line 6 has a shape that curves gently more than the outer edge 107 of the laminated substrate 1. In other words, the connection portion 613 of the RF signal line 6 bends gently by 180 degrees, so that it passes around the recess 120.

[0162] (2) Effect

[0163] Like the multilayer substrate 100C in Embodiment 4, the multilayer substrate 100E in Embodiment 6 can reduce AC resistance.

[0164] Furthermore, the multilayer substrate 100E according to Embodiment 6 also includes RF signal lines 6.

[0165] According to the above structure, in addition to the transmission of signals based on AC signal line 2, it is also possible to utilize the transmission of high-frequency signals based on RF signal line 6.

[0166] Furthermore, in the multilayer substrate 100E according to Embodiment 6, when viewed from the thickness direction D1 of the multilayer substrate 1, the connecting portion 613 of the RF signal line 6 formed in the first portion 61 of the first transmission line region 101 and the third portion 63 formed in the third transmission line region 103E has a shape that is gently curved compared to the outer edge 107 of the multilayer substrate 1.

[0167] Based on the above structure, impedance deviation of RF signal line 6 can be suppressed.

[0168] (Implementation Method 7)

[0169] Reference Figures 22-25The multilayer substrate 100F according to Embodiment 7 will be described. Regarding the multilayer substrate 100F according to Embodiment 7, compared with the multilayer substrate 100E according to Embodiment 6 (see...), Figures 18-21 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figures 22-25 In each of the figures, with Figures 18-21 Similarly, orthogonal coordinates with three mutually orthogonal axes—X, Y, and Z—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 24 The axis of ) is marked as the Z-axis.

[0170] (1) Structure

[0171] The difference between the multilayer substrate 100F and the multilayer substrate 100E involved in Embodiment 7 is that the third transmission line region 103E in the multilayer substrate 100E of Embodiment 6 is not present.

[0172] In the multilayer substrate 100F, the width of the stacked substrate 1 in the width direction of the plurality of signal lines 21 to 24 is fixed. In the multilayer substrate 100F, the area of ​​the conductor in the cross-section of the first transmission line region 101, which is orthogonal to the direction in which the first transmission line region 101 and the second transmission line region 102 are arranged, is smaller than the area of ​​the conductor in the cross-section of the second transmission line region 102, which is orthogonal to the direction in which the first transmission line region 101 and the second transmission line region 102 are arranged.

[0173] (2) Effect

[0174] Like the multilayer substrate 100E in Embodiment 6, the multilayer substrate 100F in Embodiment 7 can reduce AC resistance.

[0175] Furthermore, in the multilayer substrate 100F according to Embodiment 7, the total cross-sectional area of ​​the multiple signal lines 21 to 24 and the multiple ground electrodes 41 to 44 in the cross-section of the first transmission line region 101 orthogonal to the length direction of the multiple signal lines 21 to 24 is smaller than the total cross-sectional area of ​​the multiple signal lines 21 to 24 and the multiple ground electrodes 41 to 44 in the cross-section of the second transmission line region 102 orthogonal to the length direction of the multiple signal lines 21 to 24.

[0176] According to the above structure, the multilayer substrate 100F is more easily bent in the first transmission line region 101 than in the second transmission line region 102.

[0177] (Implementation Method 8)

[0178] Reference Figure 26The multilayer substrate 100G according to Embodiment 8 will be described. Regarding the multilayer substrate 100G according to Embodiment 8, compared with the multilayer substrate 100F according to Embodiment 7 (see...), Figures 22-25 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figure 26 In, with Figures 22-25 Similarly, orthogonal coordinates with three mutually orthogonal axes—the X-axis, Y-axis, and Z-axis—are used for labeling.

[0179] (1) Structure

[0180] The difference between the multilayer substrate 100G in Embodiment 8 and the multilayer substrate 100F in Embodiment 7 is that, as Figure 26 As shown, the first transmission line region 101 is curved.

[0181] In the multilayer substrate 100G, the first transmission line region 101 is bent by plastic deformation of thermoplastic resin and the multilayer substrate 100G itself maintains its shape.

[0182] (2) Effect

[0183] Like the multilayer substrate 100F in Embodiment 7, the multilayer substrate 100G in Embodiment 8 can reduce AC resistance.

[0184] Furthermore, since the multilayer substrate 100G according to Embodiment 8 is bent in the first transmission line region 101, it becomes easier to configure the multilayer substrate 100G into the housing of the electronic device, for example, when the housing of the multilayer substrate 100G in the electronic device is a bent space.

[0185] (Implementation Method 9)

[0186] Reference Figures 27-30 The multilayer substrate 100H according to Embodiment 9 will be described. Regarding the multilayer substrate 100H according to Embodiment 9, compared with the multilayer substrate 100F according to Embodiment 7 (see...), Figures 22-25 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figures 27-30 In each of the figures, with Figures 22-25 Similarly, orthogonal coordinates with three mutually orthogonal axes—X, Y, and Z—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 29 The axis of ) is marked as the Z-axis.

[0187] (1) Structure

[0188] The difference between the multilayer substrate 100H in Embodiment 9 and the multilayer substrate 100F in Embodiment 7 is that, as Figure 28 as well as Figure 29As shown, it also includes a signal line 7 configured in the first transmission line area 101.

[0189] Signal line 7 is located on the side opposite to AC signal line 2 in the second ground electrode 42. Furthermore, signal line 7 is located on the side opposite to RF signal line 6 in the split ground electrode 421 of the second ground electrode 42 in the width direction of the second signal line 22. Therefore, in the multilayer substrate 100H, in a direction parallel to the X-axis, the second signal line 22, the split ground electrode 421, the RF signal line 6, the split ground electrode 422, and signal line 7 are arranged in the following order: second signal line 22, split ground electrode 421, RF signal line 6, split ground electrode 422, and signal line 7.

[0190] Signal route 7 transmits a signal different from the signal transmitted on AC signal route 2. Signal route 7 is, for example, a digital signal route that transmits digital signals.

[0191] (2) Effect

[0192] Like the multilayer substrate 100F in Embodiment 7, the multilayer substrate 100H in Embodiment 9 can reduce AC resistance.

[0193] Furthermore, the multilayer substrate 100H according to embodiment 9 has a signal path 7 in addition to the AC signal line 2, so it can be used for signal transmission based on the signal path 7 in addition to signal transmission based on the AC signal line 2.

[0194] (Implementation Method 10)

[0195] Reference Figures 31-34 The multilayer substrate 100I according to Embodiment 10 will be described. Regarding the multilayer substrate 100I according to Embodiment 10, compared with the multilayer substrate 100B according to Embodiment 3 (see...), Figures 9-11 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figures 31-34 In each of the figures, with Figures 9-11 Similarly, orthogonal coordinates with three mutually orthogonal axes—X, Y, and Z—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 32 The axis of ) is marked as the Z-axis.

[0196] (1) Structure

[0197] In the multilayer substrate 100I, a first connecting conductor 31 among a plurality of connecting conductors is disposed at the end of a signal line 21 adjacent to a ground electrode 41 at the boundary BL1 of the first transmission line region 101 and the second transmission line region 102. Viewed from the thickness direction D1 of the multilayer substrate 1, as shown... Figure 34As shown, the center C1 of the first connecting conductor 31 is located within the maximum length LM1 of the first connecting conductor 31, extending from the end edge 211 of the signal line 21. The center C1 of the first connecting conductor 31 lies on a vertical line PL1, which is established at the end edge 211 of the signal line 21, such that it passes through the first point 311 in the first connecting conductor 31 closest to the end edge 211 of the signal line 21. The distance between the second point 312, which is furthest from the end edge 211 of the signal line 21 on the vertical line PL1, and the center C1 is the same as the distance between the first point 311 and the center C1. The maximum length LM1 is the length between the first point 311 and the second point 312.

[0198] (2) Effect

[0199] The multilayer substrate 100I according to Embodiment 10, like the multilayer substrate 100B according to Embodiment 3, can reduce AC resistance.

[0200] Furthermore, in the multilayer substrate 100I according to Embodiment 10, the first connecting conductor 31 among the plurality of connecting conductors is disposed at the end of the signal line 21 adjacent to a ground electrode 41 at the boundary BL1 of the first transmission line region 101 and the second transmission line region 102. Viewed from the thickness direction D1 of the multilayer substrate 1, the center C1 of the first connecting conductor 31 is within the range of the maximum length LM1 of the first connecting conductor 31 from the end edge 211 of the signal line 21.

[0201] According to the above structure, the AC signal line 2 can be utilized more effectively in the first transmission line region 101, and the AC resistance can be further reduced.

[0202] (Implementation Method 11)

[0203] Reference Figures 35-37 The multilayer substrate 100J according to Embodiment 11 will be described. Regarding the multilayer substrate 100J according to Embodiment 11, compared with the multilayer substrate 100 according to Embodiment 1 (see...), Figures 1-4 The same constituent elements are labeled with the same reference numerals and descriptions are omitted. Figures 35-37 In each of the figures, with Figures 1-4 Similarly, orthogonal coordinates with three mutually orthogonal axes—X, Y, and Z—are defined along the thickness direction D1 of the laminated substrate 1 (refer to...). Figure 36 The axis of ) is marked as the Z-axis.

[0204] (1) Structure

[0205] The difference between the multilayer substrate 100J according to Embodiment 11 and the multilayer substrate 100 according to Embodiment 1 is that the thickness T1 of the first transmission line region 101 in the thickness direction D1 of the stacked substrate 1 (refer to...) Figure 36 The thickness T2 of the second transmission line region 102 in the thickness direction D1 of the laminated substrate 1 (refer to) Figure 37 The thickness T1 of the first transmission line region 101 in the thickness direction D1 of the laminated substrate 1 (refer to...) is different. In this embodiment, the thickness T1 of the first transmission line region 101 in the thickness direction D1 of the laminated substrate 1 (refer to...) is different. Figure 36 The thickness T2 of the second transmission line region 102 in the thickness direction D1 of the laminated substrate 1 (refer to) Figure 37 )Thin.

[0206] In the multilayer substrate 100J, the thickness of the laminate 1 differs in the first transmission line region 101 and the second transmission line region 102. In the first transmission line region 101, the laminate 1 has a stacked structure with four insulating layers 11 to 14, while in the second transmission line region 102, the laminate 1 has a stacked structure with five insulating layers 11 to 15. Insulating layer 15 is stacked on insulating layer 14. The material of insulating layer 15 is the same as that of insulating layers 11 to 14. Furthermore, the second transmission line region 102 of the multilayer substrate 100J also has a signal line 25 disposed on insulating layer 15 and a ground electrode 45. Additionally, the second transmission line region 102 also has a connecting conductor 35 connecting signal lines 25 and 24, and a connecting conductor 55 connecting ground electrodes 45 and 44. The material of signal line 25 is, for example, the same as that of the other signal lines 21 to 24. Viewed from the thickness direction D1 of the laminated substrate 1, multiple signal lines 21, 22, 23, 24, and 25 overlap each other. Signal line 25 has a line width W25. The material of the connecting conductor 35 is, for example, the same as the material of the first connecting conductor 31 to the fourth connecting conductor 34. The material of the ground electrode 45 is, for example, the same as the material of the other ground electrodes 41 to 44. Viewed from the thickness direction D1 of the laminated substrate 1, multiple ground electrodes 41, 42, 43, 44, and 45 overlap each other. Ground electrode 45 has an electrode width W45. The material of the connecting conductor 55 is, for example, the same as the material of the fifth connecting conductor 51 to the eighth connecting conductor 54.

[0207] (2) Effect

[0208] The multilayer substrate 100J according to Embodiment 11, like the multilayer substrate 100 according to Embodiment 1, can achieve a reduction in AC resistance.

[0209] Furthermore, in the multilayer substrate 100J according to embodiment 11, the thickness T1 of the first transmission line region 101 in the thickness direction D1 of the stacked substrate 1 is thinner than the thickness T2 of the second transmission line region 102 in the thickness direction D1 of the stacked substrate 1.

[0210] Based on the above structure, the multilayer substrate 100J can be easily bent in the first transmission line region 101.

[0211] The embodiments 1 to 11 described above are merely one of the various embodiments of the present invention. As long as the purpose of the present invention can be achieved, the embodiments 1 to 11 described above can be modified in various ways according to design, etc., and can also be appropriately combined.

[0212] For example, the material of each of the plurality of insulating layers 11 to 14 may also be polyimide. In this case, the plurality of first connecting conductors 31, the plurality of second connecting conductors 32, the plurality of third connecting conductors 33, the plurality of fourth connecting conductors 34, the plurality of fifth connecting conductors 51, the plurality of sixth connecting conductors 52, the plurality of seventh connecting conductors 53, and the plurality of eighth connecting conductors 54 may each be formed by a through-hole plating layer. Alternatively, the interconnected first connecting conductors 31 and second connecting conductors 32 may be formed by a single through-hole plating layer, and the interconnected fifth connecting conductors 51 and sixth connecting conductors 52 may also be formed by a single through-hole plating layer. The material of the through-hole plating layer may be, for example, copper. Furthermore, the laminated substrate 1 may also have an adhesive layer between two adjacent insulating layers in the thickness direction D1 of the laminated substrate 1, which is located among the plurality of insulating layers 11 to 14.

[0213] Furthermore, the multilayer substrates 100, 100A to 100F, and 100H to 100J can also be bent in the first transmission line region 101 in the same manner as the multilayer substrate 100G. Additionally, the multilayer substrates 100, 100A to 100J can also be bent in the second transmission line region 102.

[0214] Furthermore, the multilayer substrates 100, 100A to 100I may also be configured similarly to multilayer substrate 100J, such that the thickness of the first transmission line region 101 in the thickness direction D1 of the stacked substrate 1 is thinner than the thickness of the second transmission line region 102 in the thickness direction D1 of the stacked substrate 1. Additionally, in multilayer substrates 100, 100A to 100I, the thickness of the second transmission line region 102 may also be thinner than the thickness of the first transmission line region 101.

[0215] In addition, the multilayer substrates 100, 100A to 100J can also be bent in the second transmission line region 102.

[0216] Furthermore, the multilayer substrates 100, 100A-100J may also include at least one of a first cover layer disposed on one main surface of the laminated substrate 1 and a second cover layer disposed on another main surface of the laminated substrate 1. The first and second cover layers each comprise, for example, a polyimide film and an adhesive layer. The adhesive layer is made of, for example, acrylic resin, silicone resin, epoxy resin, or polyurethane resin. If there are no bent portions in the multilayer substrates 100, 100A-100J, the first and second cover layers are not limited to a structure comprising a polyimide film and an adhesive layer; for example, they may be resist layers. The resist layer can be formed, for example, using spin coating and photolithography techniques.

[0217] (Way)

[0218] The following methods are disclosed in this specification.

[0219] The multilayer substrate (100; 100A; 100B; 100C; 100D; 100E; 100F; 100G; 100H; 100I; 100J) according to the first embodiment includes a multilayer substrate (1), an AC signal line (2), and multiple ground electrodes (41-44). Multiple insulating layers (11-14) are stacked on the multilayer substrate (1). The AC signal line (2) is formed on the multilayer substrate (1). The AC signal line (2) has multiple signal lines (21-24) that are separated from each other in the thickness direction (D1) of the multilayer substrate (1), and the multiple signal lines (21-24) are electrically connected by multiple connecting conductors that penetrate at least one of the multiple insulating layers (11-14) in the thickness direction (D1). Multiple ground electrodes (41-44) are formed on the multilayer substrate (1). Multiple grounding electrodes (41-44) are separated from each other in the thickness direction (D1) and adjacent to multiple signal lines (21-24) in the width direction. In the first transmission line region (101) with the smallest maximum line width among the multiple signal lines (21-24), the multiple signal lines (21-24) do not overlap with any of the multiple grounding electrodes (41-44) in the thickness direction (D1). In the second transmission line region (102) with the largest maximum line width among the multiple signal lines (21-24), one of the multiple grounding electrodes (41) overlaps with one of the grounding electrodes (41) and the signal lines (22-24) other than the signal line (21) adjacent to the grounding electrode (41).

[0220] This method allows for the reduction of AC resistance.

[0221] The multilayer substrates (100; 100A; 100B; 100C; 100D; 100E; 100F; 100G; 100H; 100I; 100J) involved in the second method are based on the first method. In the second transmission line region (102), among the multiple signal lines (21-24), more than half of the area of ​​the signal line (22) adjacent to a ground electrode (41) in the thickness direction (D1) overlaps with a ground electrode (41) in the thickness direction (D1).

[0222] According to this method, compared with the case where half of the region of the signal line (22) in the thickness direction (D1) of the laminated substrate (1) overlaps with a ground electrode (41), the imbalance of current density in the width direction of the signal line (22-24) can be further reduced, and the AC resistance can be further reduced.

[0223] The multilayer substrate (100B) involved in the third method is based on the first method. In the second transmission line region (102), among the multiple signal lines (21 to 24), the entire region of the signal line (22) that is adjacent to a ground electrode (41) in the thickness direction (D1) overlaps with a ground electrode (41) in the thickness direction (D1).

[0224] This method can improve noise resistance.

[0225] In the multilayer substrate (100C; 100D) involved in the fourth method, in any of the first to third methods, when the maximum line width in the first transmission line region (101) is set to X1 and the maximum line width in the second transmission line region (102) is set to X2, in the third transmission line region (103) where the maximum line width among the plurality of signal lines (21 to 24) is greater than X1 and less than (X1+X2) / 2, in the thickness direction (D1), the plurality of signal lines (21 to 24) do not overlap with any of the plurality of ground electrodes (41 to 44).

[0226] According to this method, when the AC signal line (2) is formed across the first transmission line region (101), the second transmission line region (102), and the third transmission line region (103), it is possible to reduce the AC resistance.

[0227] In the multilayer substrate (100C) involved in the fifth method, in any of the first to fourth methods, the outline width (W1) in the width direction of the plurality of signal lines (21 to 24) in the first transmission line region (101) and the outline width (W2) in the width direction of the plurality of signal lines (21 to 24) in the second transmission line region (102) are the same.

[0228] In the multilayer substrates (100; 100A; 100B; 100D; 100E; 100F; 100G; 10H; 100I; 100J) involved in the sixth method, in any of the first to fourth methods, the outline width (W2) of the plurality of signal lines (21 to 24) in the second transmission line region (102) in the width direction is wider than the outline width (W1) of the plurality of signal lines (21 to 24) in the width direction in the first transmission line region (101).

[0229] According to this method, regarding the AC signal line (2), the AC resistance in the first transmission line region (101) and the second transmission line region (102) can be further reduced.

[0230] Regarding the multilayer substrate (100) involved in the seventh method, in any of the first to fourth methods, the total cross-sectional area of ​​the multiple signal lines (21 to 24) and the multiple ground electrodes (41 to 44) in the cross-section of the first transmission line region (101) orthogonal to the length direction of the multiple signal lines (21 to 24) is smaller than the total cross-sectional area of ​​the multiple signal lines (21 to 24) and the multiple ground electrodes (41 to 44) in the cross-section of the second transmission line region (102) orthogonal to the length direction of the multiple signal lines (21 to 24).

[0231] According to this method, the multilayer substrate (100) is more easily bent in the first transmission line region (101) compared to the second transmission line region (102).

[0232] Regarding the multilayer substrate (100G) involved in the eighth method, in any of the first to seventh methods, the first transmission line region (101) is bent.

[0233] In the multilayer substrates (100; 100A; 100B; 100C; 100D) involved in the 9th aspect, in any of the 1st to 8th aspects, the material of each of the plurality of insulating layers (11 to 14) comprises a thermoplastic resin.

[0234] According to this method, the flexibility of multilayer substrates (100; 100A; 100B; 100C; 100D) can be improved.

[0235] Regarding the multilayer substrate (100E; 100F; 100G; 100H) involved in the 10th method, in any of the 1st to 9th methods, an RF signal line (6) is also provided. The RF signal line (6) is formed on the multilayer substrate (1). The RF signal line (6) is arranged to span the first transmission line region (101) and the second transmission line region (102).

[0236] According to this method, in addition to the transmission of signals based on AC signal lines (2), it is also possible to utilize the transmission of high-frequency signals based on RF signal lines (6).

[0237] Regarding the multilayer substrate (100E) according to the 11th embodiment, in any of the 1st to 3rd embodiments, it further comprises: a third transmission line region (103E) located on the side opposite to the second transmission line region (102) in the first transmission line region (101); and RF signal lines (6) formed on the multilayer substrate (1). A plurality of signal lines (21 to 24) are formed spanning the first transmission line region (101), the second transmission line region (102), and the third transmission line region (103E). The width direction of the plurality of signal lines (21 to 24) in the first transmission line region (101) is orthogonal to the width direction of the plurality of signal lines (21 to 24) in the third transmission line region (103E). The RF signal line (6) includes a first portion (61) formed in the first transmission line region (101), a second portion (62) formed in the second transmission line region (102), and a third portion (63) formed in the third transmission line region (103E). Viewed from the thickness direction (D1) of the laminated substrate (1), the connecting portion (613) of the first portion (61) and the third portion (63) in the RF signal line (6) has a shape that is gently curved compared to the outer edge of the laminated substrate (1).

[0238] According to this method, the impedance deviation of the RF signal line (6) can be suppressed.

[0239] Regarding the multilayer substrate (100H) involved in the 12th method, in any of the 1st to 11th methods, a signal path (7) is also provided. The signal path (7) is only configured in the first transmission line region (101) between the first transmission line region (101) and the second transmission line region (102).

[0240] According to this method, in addition to the transmission of signals based on AC signal line (2), it is also possible to utilize the transmission of other signals based on signal line (7).

[0241] In the multilayer substrate (100; 100A; 100B; 100C; 100D; 100E; 100F; 100G; 100H; 100I; 100J) involved in the 13th method, in any of the 1st to 12th methods, the first connecting conductor (1st connecting conductor 31) of the multiple connecting conductors, which is disposed at the end of the signal line (21) adjacent to a ground electrode (41) at the boundary (BL1) between the first transmission line region (101) and the second transmission line region (102). Viewed from the thickness direction (D1) of the laminated substrate (1), the center (C1) of the connecting conductor (first connecting conductor 31) disposed on the signal line (21) adjacent to a ground electrode (41) is within the range of the maximum length (LM1) of the connecting conductor (first connecting conductor 31) from the end edge (211) of the signal line (21) adjacent to a ground electrode (41).

[0242] According to this method, the AC signal line (2) can be utilized more effectively in the first transmission line area (101), and the AC resistance can be further reduced.

[0243] In the multilayer substrate (100J) involved in the 14th method, in any of the 1st to 13th methods, the thickness (T1) of the first transmission line region (101) in the thickness direction (D1) of the stacked substrate (1) and the thickness (T2) of the second transmission line region (102) in the thickness direction (D1) of the stacked substrate (1) are different.

[0244] According to this method, the flexibility of the thinner of the first transmission line region (101) and the second transmission line region (102) in the multilayer substrate (100J) can be improved.

[0245] Explanation of reference numerals in the attached figures

[0246] 1: Laminated substrate;

[0247] 11, 12, 13, 14, 15: Insulation layer;

[0248] 2: AC signal lines;

[0249] 21, 22, 23, 24, 25: Signal lines;

[0250] 31: First connecting conductor;

[0251] 32: Second connecting conductor;

[0252] 33: Third connecting conductor;

[0253] 34: Fourth connecting conductor;

[0254] 41, 42, 43, 44, 45: Grounding electrodes;

[0255] 51: Fifth connecting conductor;

[0256] 52: The 6th connecting conductor;

[0257] 53: The 7th connecting conductor;

[0258] 54: The 8th connecting conductor;

[0259] 6: RF signal line;

[0260] 61: Part 1;

[0261] 62: Part 2;

[0262] 63: Part 3;

[0263] 613: Connecting part;

[0264] 7: Signal route;

[0265] 100, 100A, 100B, 100C, 100D, 100E, 100F, 100G, 100H, 100I, 100J: Multilayer substrates;

[0266] 101: First transmission line area;

[0267] 102: Second transmission line area;

[0268] 103: Third transmission line area;

[0269] 103E: Third transmission line area;

[0270] C1: Center;

[0271] D1: Thickness direction;

[0272] LM1: Maximum length;

[0273] W1: Overall width;

[0274] W2: External width;

[0275] W21, W22, W23, W24, W25: Line width.

Claims

1. A multilayer substrate comprising: A laminated substrate having multiple insulating layers stacked on top of it; An AC signal line is formed on the laminated substrate, having a plurality of signal lines separated from each other in the thickness direction of the laminated substrate, the plurality of signal lines being electrically connected by a plurality of connecting conductors penetrating one of the plurality of insulating layers in the thickness direction; and Multiple ground electrodes are formed on the laminated substrate, separated from each other in the thickness direction, and adjacent to the multiple signal lines in the width direction. In the first transmission line region where the maximum line width of the plurality of signal lines is the smallest, in the thickness direction, the plurality of signal lines do not overlap with any of the plurality of ground electrodes. In the second transmission line region with the largest maximum line width among the plurality of signal lines, one of the plurality of ground electrodes overlaps with a signal line other than the signal line adjacent to the ground electrode among the plurality of signal lines.

2. The multilayer substrate according to claim 1, wherein, In the second transmission line area, In the plurality of signal lines, in the signal line adjacent to the ground electrode in the thickness direction, more than half of the region in the width direction overlaps with the ground electrode in the thickness direction.

3. The multilayer substrate according to claim 1, wherein, In the second transmission line area, In the plurality of signal lines, in the signal line adjacent to the ground electrode in the thickness direction, the entire region overlaps with the ground electrode in the thickness direction.

4. The multilayer substrate according to any one of claims 1 to 3, wherein, When the maximum line width in the first transmission line region is set to X1 and the maximum line width in the second transmission line region is set to X2, in the third transmission line region where the maximum line width among the plurality of signal lines is greater than X1 and less than (X1+X2) / 2, in the thickness direction, the plurality of signal lines do not overlap with any of the plurality of ground electrodes.

5. The multilayer substrate according to any one of claims 1 to 4, wherein, The width of the plurality of signal lines in the first transmission line region is the same as the width of the plurality of signal lines in the second transmission line region.

6. The multilayer substrate according to any one of claims 1 to 4, wherein, The width of the plurality of signal lines in the second transmission line region is wider in the width direction than the width of the plurality of signal lines in the first transmission line region.

7. The multilayer substrate according to any one of claims 1 to 4, wherein, The total cross-sectional area of ​​the plurality of signal lines and the plurality of ground electrodes in the cross-section of the first transmission line region orthogonal to the length direction of the plurality of signal lines is smaller than the total cross-sectional area of ​​the plurality of signal lines and the plurality of ground electrodes in the cross-section of the second transmission line region orthogonal to the length direction of the plurality of signal lines.

8. The multilayer substrate according to any one of claims 1 to 7, wherein, It bends in the first transmission line region.

9. The multilayer substrate according to any one of claims 1 to 8, wherein, The material of each of the plurality of insulating layers comprises a thermoplastic resin.

10. The multilayer substrate according to any one of claims 1 to 9, wherein, It also includes RF signal lines formed on the laminated substrate. The RF signal line is configured to span the first transmission line region and the second transmission line region.

11. The multilayer substrate according to any one of claims 1 to 3, wherein, It also has: The third transmission line region is located on the opposite side of the first transmission line region to the second transmission line region. as well as RF signal lines are formed on the laminated substrate. The plurality of signal lines are formed by crossing the first transmission line region, the second transmission line region, and the third transmission line region. The width direction of the plurality of signal lines in the first transmission line region is orthogonal to the width direction of the plurality of signal lines in the third transmission line region. The RF signal line includes a first portion formed in the first transmission line region, a second portion formed in the second transmission line region, and a third portion formed in the third transmission line region. Viewed from the thickness direction of the laminated substrate, the connection portion of the first and third portions in the RF signal line has a shape that is gently curved compared to the outer edge of the laminated substrate.

12. The multilayer substrate according to any one of claims 1 to 11, wherein, It also includes a signal route configured only in the first transmission line area, which is located only in the first transmission line area and the second transmission line area.

13. The multilayer substrate according to any one of claims 1 to 12, wherein, Of the plurality of connecting conductors, the connecting conductor of the signal line disposed at the end of the signal line adjacent to the ground electrode, which is located at the boundary between the first transmission line region and the second transmission line region, is disposed at the end of the signal line adjacent to the ground electrode. Viewed from the thickness direction of the laminated substrate, the center of the connecting conductor of the signal line adjacent to the ground electrode is within the maximum length of the connecting conductor from the end edge of the signal line adjacent to the ground electrode.

14. The multilayer substrate according to any one of claims 1 to 13, wherein, The thickness of the first transmission line region in the thickness direction of the laminated substrate is different from the thickness of the second transmission line region in the thickness direction of the laminated substrate.

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