Multilayer substrate

Abstract

The utility model provides a multilayer substrate, which at least comprises a laminated body having a structure in which a plurality of insulator layers including a first insulator layer are laminated along a Z axis, and the first insulator layer has a positive main surface and a negative main surface; a first conductor layer and a second conductor layer located on the front main surface of the first insulator layer; a first columnar conductor and a second columnar conductor provided inside a through hole penetrating through the first insulator layer; and a connection conductor that electrically connects the conductors in the stacking direction, the positive-side end of the first columnar conductor in the Z-axis is in contact with the first conductor layer and the negative-side end of the first columnar conductor is connected to the columnar conductor or the conductor layer via the connection conductor, and the positive-side end of the second columnar conductor in the Z-axis is in contact with the second conductor layer and the negative-side end of the second columnar conductor is not in contact with either of the conductors. The first columnar conductor and the second columnar conductor are made of the same material, and the connecting conductor, the first columnar conductor and the second columnar conductor are made of different materials and are made of a mixture or alloy of resin and metal.

Description

Technical Field

[0001] This invention relates to a multilayer substrate having a structure in which multiple insulating layers are stacked. Background Technology

[0002] As a prior art invention concerning multilayer substrates, for example, a method for manufacturing a wiring circuit board is known as described in Patent Document 1. In this method, a seed film and wiring are overlapped and formed on a substrate insulating layer. The seed film and wiring are made of conductors. Therefore, it is possible to achieve low resistance in the current path including the seed film and wiring.

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-027927 Utility Model Content

[0006] Problems to be solved by utility models

[0007] As described above, in the field of wiring circuit boards as described in Patent Document 1, it is desirable to include seed films and low resistance in the current paths of wiring.

[0008] Therefore, the purpose of this invention is to provide a multilayer substrate that can achieve low resistance in current path design.

[0009] Technical solutions for solving the problem

[0010] One embodiment of this utility model involves a multilayer substrate comprising at least a laminate, a first conductor layer, a second conductor layer, a first columnar conductor, a second columnar conductor, and a connecting conductor.

[0011] The laminate has a structure in which multiple insulating layers, including a first insulating layer, are stacked along the Z-axis.

[0012] The first insulating layer has a positive principal surface and a negative principal surface located on the negative side of the Z-axis, which is closer to the positive principal surface.

[0013] The first conductor layer and the second conductor layer are located on the positive principal plane of the first insulator layer.

[0014] The first columnar conductor and the second columnar conductor are disposed inside the through hole that penetrates the first insulating layer along the Z-axis.

[0015] The end of the first columnar conductor on the positive side of the Z-axis is in contact with the first conductor layer.

[0016] The connecting conductor is a conductor that electrically connects the conductors in the stacked direction.

[0017] The negative end of the first columnar conductor on the Z-axis is connected to the columnar conductor or conductor layer via the connecting conductor.

[0018] The end of the second columnar conductor on the positive side of the Z-axis is in contact with the second conductor layer.

[0019] The end of the second cylindrical conductor on the negative side of the Z-axis does not contact any other conductor.

[0020] The first columnar conductor and the second columnar conductor are made of the same material.

[0021] The material of the connecting conductor is different from the materials of the first columnar conductor and the second columnar conductor.

[0022] The material of the connecting conductor is a mixture or alloy of resin and metal.

[0023] One aspect of this utility model relates to a method for manufacturing a multilayer substrate, comprising a first preparation step, a through-hole forming step, a conductor layer forming step, a columnar conductor forming step, a second preparation step, and a pressing step, wherein...

[0024] In the first preparation step, a first insulating layer is prepared, the first insulating layer having a positive principal surface and a negative principal surface located on the negative side of the positive principal surface closer to the Z-axis, and a metal foil covering the positive principal surface is provided.

[0025] In the through-hole forming process, a first through-hole and a second through-hole are formed along the Z-axis in the first insulating layer.

[0026] In the conductor layer formation process, the first conductor layer and the second conductor layer are formed by processing the metal foil.

[0027] In the columnar conductor forming process, a first columnar conductor and a second columnar conductor are formed in the first through hole and the second through hole, respectively.

[0028] In the second preparation step, a second insulating layer with a connecting conductor is prepared.

[0029] In the pressing process, multiple insulating layers, including the first insulating layer and the second insulating layer, are stacked and pressed together, such that the first insulating layer is located on the positive side of the Z-axis closer than the second insulating layer.

[0030] The end of the first columnar conductor on the positive side of the Z-axis is in contact with the first conductor layer.

[0031] The end of the second columnar conductor on the positive side of the Z-axis is in contact with the second conductor layer.

[0032] The end of the first columnar conductor on the negative side of the Z-axis is connected to the connecting conductor.

[0033] Utility Model Effect

[0034] According to the multilayer substrate involved in this utility model, it is possible to achieve low resistance in the current path. Attached Figure Description

[0035] Figure 1 This is an exploded perspective view of the multilayer substrate 10.

[0036] Figure 2 This is a cross-sectional view of the multilayer substrate 10.

[0037] Figure 3 This is a cross-sectional view of the multilayer substrate 10 during manufacturing.

[0038] Figure 4 This is a cross-sectional view of the multilayer substrate 10 during manufacturing.

[0039] Figure 5 This is a cross-sectional view of the multilayer substrate 10 during manufacturing.

[0040] Figure 6 This is a cross-sectional view of the multilayer substrate 10 during manufacturing.

[0041] Figure 7 This is a cross-sectional view of the multilayer substrate 10 during manufacturing.

[0042] Figure 8 This is a cross-sectional view of the multilayer substrate 10 during manufacturing.

[0043] Figure 9 This is a cross-sectional view of the multilayer substrate 10 during manufacturing.

[0044] Figure 10 This is a cross-sectional view of the multilayer substrate 10 during manufacturing.

[0045] Figure 11 This is a cross-sectional view of the multilayer substrate 10a.

[0046] Figure 12 This is a cross-sectional view of the multilayer substrate 10b.

[0047] Figure 13 This is a top view of the insulating layer 16c of the multilayer substrate 10c.

[0048] Figure 14 This is a top view of the insulating layer 16c of the multilayer substrate 10d.

[0049] Figure 15This is a rear view of the multilayer substrate 10d in use.

[0050] Figure 16 This is a top view of the insulating layer 16c of the multilayer substrate 10e. Detailed Implementation

[0051] (Implementation Method)

[0052] [Structure of multilayer substrates]

[0053] Hereinafter, the structure of the multilayer substrate 10 according to the embodiments of the present invention will be described with reference to the accompanying drawings. Figure 1 This is an exploded perspective view of the multilayer substrate 10. Figure 2 This is a cross-sectional view of the multilayer substrate 10. Figure 2 In, it is shown Figure 1 The cross-section at point AA. Additionally, at... Figure 1 In the figure, only representative cylindrical conductors v1a~v1d, v2a~v2d, and v3a~v3d from among the multiple cylindrical conductors v1a~v1d, v2a~v2d, and v3a~v3d are labeled with the reference numerals.

[0054] In this specification, directions are defined as follows: The stacking direction of the laminate 12 of the multilayer substrate 10 is defined as the up-down direction. Furthermore, the up-down direction coincides with the Z-axis direction. The up direction is the positive direction of the Z-axis. The down direction is the negative direction of the Z-axis. Furthermore, the directions in which the signal conductor layer 20a and the power conductor layer 20b of the multilayer substrate 10 extend are defined as the left-right direction. Furthermore, viewed in the up-down direction, the linewidth direction of the signal conductor layer 20a and the power conductor layer 20b is defined as the front-back direction. The up-down direction, the front-back direction, and the left-right direction are orthogonal to each other. Additionally, the up and down directions in the up-down direction can be interchanged, the left and right directions in the left-right direction can be interchanged, and the front and back directions in the front-back direction can be interchanged.

[0055] Hereinafter, X refers to a component or part of the multilayer substrate 10. In this specification, unless otherwise specified, the parts of X are defined as follows: Front portion of X means the front half of X. Rear portion of X means the rear half of X. Left portion of X means the left half of X. Right portion of X means the right half of X. Upper portion of X means the upper half of X. Lower portion of X means the lower half of X. Front end of X means the end in the forward direction of X. Rear end of X means the end in the rear direction of X. Left end of X means the end in the left direction of X. Right end of X means the end in the right direction of X. Upper end of X means the end in the upward direction of X. Lower end of X means the end in the downward direction of X. Front end of X means the front end of X and its vicinity. Rear end of X means the rear end of X and its vicinity. Left end of X means the left end of X and its vicinity. The right end of X refers to the right side of X and its vicinity. The upper end of X refers to the upper part of X and its vicinity. The lower end of X refers to the lower part of X and its vicinity.

[0056] First, refer to Figure 1 The structure of the multilayer substrate 10 will be described. The multilayer substrate 10 transmits high-frequency signals. In electronic devices such as smartphones, the multilayer substrate 10 is used to electrically connect two circuits. For example... Figure 1 As shown, the multilayer substrate 10 includes a laminate 12, protective layers 18a and 18b, a signal conductor layer 20a, a power conductor layer 20b, a first ground conductor layer 22, a second ground conductor layer 24, ground conductor layers 26a, 26b, 28a, 28b, 30a, and 30b, multiple columnar conductors v1a to v1d, multiple columnar conductors v2a to v2d, multiple columnar conductors v3a to v3d, a columnar conductor v10, and connecting conductors v11d, v12d, and v13d. The connecting conductors v11d, v12d, and v13d are made of different materials than the columnar conductors v1c to v3c and v1d to v3d.

[0057] The laminate 12 has a plate shape. Therefore, the laminate 12 has an upper principal surface (positive principal surface) and a lower principal surface (negative principal surface) located below the upper principal surface (positive principal surface) (on the negative side of the Z-axis). The upper and lower principal surfaces of the laminate 12 have rectangular shapes with long sides extending along the left and right axes. Therefore, the length of the laminate 12 in the left-right direction is longer than the length of the laminate 12 in the front-back direction. The laminate 12 is flexible.

[0058] like Figure 1As shown, the laminate 12 has a structure in which insulating layers 16a to 16d, including insulating layer 16c (first insulating layer), are stacked along the vertical axis (Z-axis). The insulating layers 16a to 16d are arranged sequentially from top to bottom. Each insulating layer 16a to 16d has an upper main surface (positive main surface) and a lower main surface (negative main surface) located below the upper main surface (positive main surface) (on the negative side of the Z-axis). The material of the insulating layers 16a to 16d is, for example, a thermoplastic resin. The thermoplastic resin is, for example, a liquid crystal polymer. Furthermore, in the insulating layers 16a to 16d, adjacent insulating layers are fused together.

[0059] High-frequency signals are transmitted in the signal conductor layer 20a. For example... Figure 1 As shown, signal conductor layer 20a (the third conductor layer) is located on the upper principal surface (positive principal surface) of insulator layer 16c (the first insulator layer). Viewed from below, signal conductor layer 20a has a linear shape extending along the left-right axis. Signal conductor layer 20a has an upper principal surface and a lower principal surface located below the upper principal surface. The surface roughness of the lower principal surface of signal conductor layer 20a is greater than the surface roughness of the upper principal surface of signal conductor layer 20a.

[0060] Connect the power supply potential to the power conductor layer 20b. For example... Figure 1 As shown, the power conductor layer 20b (second conductor layer) is located on the upper main surface (positive main surface) of the insulating layer 16c (first insulating layer). Viewed in the downward direction (negative direction of the Z-axis), the power conductor layer 20b has a linear shape extending along the left-right axis. Therefore, the power conductor layer 20b is parallel to the signal conductor layer 20a. In this embodiment, the power conductor layer 20b is located behind the signal conductor layer 20a. Figure 2 As shown, the linewidth Wb of the power conductor layer 20b is larger than the linewidth Wa of the signal conductor layer 20a. The power conductor layer 20b (the second conductor layer) has an upper main surface (positive main surface) and a lower main surface (negative main surface) located below the upper main surface (positive main surface) (on the negative side of the Z-axis). The surface roughness of the lower main surface (negative main surface) of the power conductor layer 20b is greater than the surface roughness of the upper main surface (positive main surface) of the power conductor layer 20b.

[0061] like Figure 1As shown, a first ground conductor layer 22 is disposed in the laminate 12. The first ground conductor layer 22 is located above the signal conductor layer 20a and the power conductor layer 20b, and overlaps with them when viewed from below. In this embodiment, the first ground conductor layer 22 is located on the upper main surface of the insulating layer 16a. Furthermore, the first ground conductor layer 22 covers approximately the entire surface of the upper main surface of the insulating layer 16a. The first ground conductor layer 22 has an upper main surface and a lower main surface located below the upper main surface. The surface roughness of the lower main surface of the first ground conductor layer 22 is greater than the surface roughness of the upper main surface of the first ground conductor layer 22. A ground potential is connected to the first ground conductor layer 22.

[0062] like Figure 1 As shown, a second ground conductor layer 24 is disposed in the laminate 12. The second ground conductor layer 24 is located below the signal conductor layer 20a and the power conductor layer 20b, and overlaps with them when viewed from below. In this embodiment, the second ground conductor layer 24 is located on the lower main surface of the insulator layer 16d. Furthermore, the second ground conductor layer 24 covers approximately the entire surface of the lower main surface of the insulator layer 16d. The second ground conductor layer 24 has an upper main surface and a lower main surface located below the upper main surface. The surface roughness of the upper main surface of the second ground conductor layer 24 is greater than the surface roughness of the lower main surface of the second ground conductor layer 24. A ground potential is connected to the second ground conductor layer 24. The signal conductor layer 20a, the first ground conductor layer 22, and the second ground conductor layer 24, as described above, have a stripline structure.

[0063] like Figure 1 As shown, ground conductor layers 26a, 28a, and 30a are disposed in the laminate 12. Viewed from below, ground conductor layers 26a, 28a, and 30a do not overlap with signal conductor layer 20a and power conductor layer 20b. In this embodiment, ground conductor layers 26a, 28a, and 30a are located on the upper main surface of insulating layer 16b. Viewed from below, ground conductor layers 26a, 28a, and 30a have a linear shape extending in the left-right direction. Viewed from below, ground conductor layer 26a is located in front of signal conductor layer 20a. Viewed from below, ground conductor layer 28a is located behind signal conductor layer 20a and in front of power conductor layer 20b. Viewed from below, ground conductor layer 30a is located behind power conductor layer 20b. Ground conductor layers 26a, 28a, and 30a have an upper main surface and a lower main surface located below the upper main surface. The surface roughness of the lower main surface of grounding conductor layers 26a, 28a, and 30a is greater than the surface roughness of the upper main surface of grounding conductor layers 26a, 28a, and 30a.

[0064] like Figure 1As shown, ground conductor layers 26b, 28b, and 30b are disposed in the laminate 12. Viewed from below, ground conductor layers 26b, 28b, and 30b do not overlap with signal conductor layer 20a and power conductor layer 20b. In this embodiment, ground conductor layers 26b, 28b, and 30b (first conductor layers) are located on the upper main surface of insulating layer 16c. Viewed from below, ground conductor layers 26b, 28b, and 30b have a linear shape extending in the left-right direction. Viewed from below, ground conductor layer 26b is located in front of signal conductor layer 20a. Viewed from below, ground conductor layer 28b is located behind signal conductor layer 20a and in front of power conductor layer 20b. Viewed from below, ground conductor layer 30b is located behind power conductor layer 20b. Ground conductor layers 26b, 28b, and 30b have an upper main surface and a lower main surface located below the upper main surface. The surface roughness of the lower main surface of grounding conductor layers 26b, 28b, and 30b is greater than that of the upper main surface of grounding conductor layers 26b, 28b, and 30b.

[0065] like Figure 2 As shown, multiple columnar conductors v1a, v2a, and v3a penetrate the insulating layer 16a along the vertical axis. The multiple columnar conductors v1a, v2a, and v3a have sections where their thickness decreases as they move upwards. The upper ends of the multiple columnar conductors v1a are in contact with the first grounding conductor layer 22. The lower ends of the multiple columnar conductors v1a are in contact with the grounding conductor layer 26a. The multiple columnar conductors v1a are arranged in a row along the left-right axis. The upper ends of the multiple columnar conductors v2a are in contact with the first grounding conductor layer 22. The lower ends of the multiple columnar conductors v2a are in contact with the grounding conductor layer 28a. The multiple columnar conductors v2a are arranged in a row along the left-right axis. The upper ends of the multiple columnar conductors v3a are in contact with the first grounding conductor layer 22. The lower ends of the multiple columnar conductors v3a are in contact with the grounding conductor layer 30a. Multiple cylindrical conductors v3a are arranged in a row along the left and right axes.

[0066] Multiple cylindrical conductors v1b, v2b, and v3b penetrate the insulating layer 16b along the vertical axis. The cylindrical conductors v1b, v2b, and v3b have sections where their thickness decreases as they move upwards. The upper ends of the cylindrical conductors v1b are in contact with the grounding conductor layer 26a. The lower ends of the cylindrical conductors v1b are in contact with the grounding conductor layer 26b. The cylindrical conductors v1b are arranged in a row along the horizontal axis. The upper ends of the cylindrical conductors v2b are in contact with the grounding conductor layer 28a. The lower ends of the cylindrical conductors v2b are in contact with the grounding conductor layer 28b. The cylindrical conductors v2b are arranged in a row along the horizontal axis. The upper ends of the cylindrical conductors v3b are in contact with the grounding conductor layer 30a. The lower ends of the cylindrical conductors v3b are in contact with the grounding conductor layer 30b. The cylindrical conductors v3b are arranged in a row along the horizontal axis.

[0067] Multiple columnar conductors v1c, v2c, and v3c (first columnar conductors) are disposed within through holes penetrating the insulating layer 16c (first insulating layer) along the vertical axis. In this embodiment, the multiple columnar conductors v1c, v2c, and v3c (first columnar conductors) penetrate the insulating layer 16c (first insulating layer) along the vertical axis. The multiple columnar conductors v1c, v2c, and v3c (first columnar conductors) have a range in which the thickness of the multiple columnar conductors v1c, v2c, and v3c decreases as they move upward (in the positive direction of the Z-axis). The upper ends of the multiple columnar conductors v1c are in contact with the grounding conductor layer 26b. The multiple columnar conductors v1c are arranged in a row along the left-right axis. The upper ends (first columnar conductors) of the multiple columnar conductors v2c are in contact with the grounding conductor layer 28b. The multiple columnar conductors v2c are arranged in a row along the left-right axis. The upper ends of multiple columnar conductors v3c are in contact with the grounding conductor layer 30b. The multiple columnar conductors v3c are arranged in a row along the left and right axes.

[0068] Multiple columnar conductors v1d, v2d, and v3d are disposed within a through-hole penetrating the insulating layer 16d along the vertical axis. However, the upper ends of the multiple columnar conductors v1d, v2d, and v3d are located below the upper main surface of the insulating layer 16d. The multiple columnar conductors v1d, v2d, and v3d have a range in which the thickness of the multiple columnar conductors v1d, v2d, and v3d decreases as they proceed downwards. The lower ends of the multiple columnar conductors v1d contact the second grounding conductor layer 24. The multiple columnar conductors v1d are arranged in a row along the left-right axis. The lower ends of the multiple columnar conductors v2d contact the second grounding conductor layer 24. The multiple columnar conductors v2d are arranged in a row along the left-right axis. The lower ends of the multiple columnar conductors v3d contact the second grounding conductor layer 24. The multiple columnar conductors v3d are arranged in a row along the left-right axis.

[0069] Multiple connecting conductors v11d, v12d, and v13d are disposed within through holes extending through the insulating layer 16d along the upper and lower axes. In this embodiment, the multiple connecting conductors v11d, v12d, and v13d are respectively located above the multiple columnar conductors v1d, v2d, and v3d. Consequently, the lower ends of the multiple columnar conductors v1c are in contact with the multiple connecting conductors v11d. The upper ends of the multiple columnar conductors v1d are in contact with the multiple connecting conductors v11d. As a result, the lower ends of the multiple columnar conductors v1c are connected to the multiple columnar conductors v1d located below the multiple columnar conductors v1c via the multiple connecting conductors v11d. The lower ends of the multiple columnar conductors v2c are in contact with the multiple connecting conductors v12d. The upper ends of the multiple columnar conductors v2d are in contact with the multiple connecting conductors v12d. As a result, the lower ends of the plurality of cylindrical conductors v2c (the first cylindrical conductors) are connected via a plurality of connecting conductors v12d to a plurality of cylindrical conductors v2d located below (on the negative side of the Z-axis) of the plurality of cylindrical conductors v2c (the first cylindrical conductors). The lower ends of the plurality of cylindrical conductors v3c are in contact with a plurality of connecting conductors v13d. The upper ends of the plurality of cylindrical conductors v3d are in contact with a plurality of connecting conductors v13d. As a result, the lower ends of the plurality of cylindrical conductors v3c are connected via a plurality of connecting conductors v13d to a plurality of cylindrical conductors v3d located below the plurality of cylindrical conductors v3c.

[0070] A columnar conductor v10 (the second columnar conductor) penetrates the insulating layer 16c (the first insulating layer) along the vertical axis. The columnar conductor v10 (the second columnar conductor) has a range where its thickness tapers upwards (in the positive direction of the Z-axis). The upper end of the columnar conductor v10 (the end on the positive side of the Z-axis) contacts the power conductor layer 20b (the second conductor layer). The lower end of the columnar conductor v10 (the end on the negative side of the Z-axis) does not contact any conductor. Furthermore, the lower end face of the columnar conductor v10 (the negative side of the Z-axis) has a shape that protrudes downwards (in the negative direction of the Z-axis). Viewed from below, the columnar conductor v10 has a linear shape extending along the left and right axes. The columnar conductor v10 extends along the power conductor layer 20b.

[0071] Furthermore, the upper end (the positive end on the Z-axis) of the pillar-shaped conductor (fourth pillar-shaped conductor) having the following structure is not connected to the signal conductor layer 20a (third conductor layer). The pillar-shaped conductor (fourth pillar-shaped conductor) penetrates the insulating layer 16c (first insulating layer) along the vertical axis (Z-axis). The lower end (the negative end on the Z-axis) of the pillar-shaped conductor (fourth pillar-shaped conductor) does not contact any conductor. However, an interlayer connection conductor electrically connected to an external electrode may also be connected to the signal conductor layer 20a.

[0072] Protective layer 18a covers the upper main surface of the laminate 12. Thus, protective layer 18a protects the first grounding conductor layer 22. Protective layer 18b covers the lower main surface of the laminate 12. Thus, protective layer 18b protects the second grounding conductor layer 24. The materials of protective layers 18a and 18b, as described above, are different from the materials of insulating layers 16a to 16d. Protective layers 18a and 18b are, for example, solder resist. The solder resist material is a composition of alkali-soluble resin, photopolymerization initiator, epoxy resin for improving heat resistance, and inorganic powder, etc.

[0073] The signal conductor layer 20a, power conductor layer 20b, first ground conductor layer 22, second ground conductor layer 24, and ground conductor layers 26a, 26b, 28a, 28b, 30a, and 30b, as described above, are formed, for example, by etching a metal foil disposed on the upper or lower main surface of the insulating layers 16a to 16d. The metal foil is, for example, copper foil. Thus, the materials of the signal conductor layer 20a, the power conductor layer 20b, the first ground conductor layer 22, the second ground conductor layer 24, and the ground conductor layers 26a, 26b, 28a, 28b, 30a, and 30b (the materials of the first conductor layer and the second conductor layer) are resin-free metals.

[0074] Furthermore, the plurality of columnar conductors v1a, v1b, v2a, v2b, and v3a, v3b are, for example, via conductors. The via conductors can be fabricated by forming through-holes in the insulating layers 16a, 16b, filling the through-holes with conductive paste, and then sintering the conductive paste. The materials of the plurality of columnar conductors v1a, v1b, v2a, v2b, and v3a, v3b are a mixture of resin and metal.

[0075] Furthermore, the plurality of columnar conductors v1c, v1d, v2c, v2d, v3c, v3d, and v10 are, for example, through-hole conductors. The through-hole conductor can be fabricated by forming through-holes in the insulating layers 16c and 16d and then performing metal plating on the through-holes. The materials of the plurality of columnar conductors v1c, v1d, v2c, v2d, v3c, v3d, and v10 are metals. For example, the metal is copper. Thus, the materials of the plurality of columnar conductors v1c, v1d, v2c, v2d, v3c, v3d (the material of the first columnar conductor), and v10 (the material of the second columnar conductor) are metals that do not contain resin. Furthermore, the materials of the signal conductor layer 20a, the power conductor layer 20b, the first ground conductor layer 22, the second ground conductor layer 24, the ground conductor layers 26a, 26b, 28a, 28b, 30a, 30b, the plurality of columnar conductors v1c, v1d, v2c, v2d, and v3c, v3d (the materials of the first conductor layer, the second conductor layer, the first columnar conductor, and the second columnar conductor) are the same.

[0076] In addition, multiple connecting conductors v11d, v12d, and v13d can be fabricated by filling the through holes formed with multiple columnar conductors v1d, v2d, and v3d with conductive paste and then sintering the conductive paste.

[0077] Multiple connecting conductors v11d, v12d, and v13d are mixtures of resin and metal. Furthermore, these connecting conductors v11d, v12d, and v13d can also be, for example, alloyed metals like solder.

[0078] [Manufacturing method of multilayer substrate 10]

[0079] Next, the manufacturing method of the multilayer substrate 10 will be described with reference to the accompanying drawings. Figures 3 to 10 This is a cross-sectional view of the multilayer substrate 10 during manufacturing.

[0080] First, such as Figure 3 As shown, the insulating layers 16a to 16c (first insulating layers) of metal foils 122, 126a, and 126b, which cover the upper main surface (positive main surface) of insulating layers 16a to 16c (first insulating layers), are prepared (first preparation step). The insulating layer 16d of metal foil 124, which covers the lower main surface of insulating layer 16d, is prepared.

[0081] Next, as Figure 4As shown, by irradiating the insulating layer 16a from below, through holes H1a, H2a, and H3a extending along the vertical axis (Z-axis) are formed in the insulating layer 16a. Furthermore, by irradiating the insulating layer 16b from below, through holes H1b, H2b, and H3b extending along the vertical axis (Z-axis) are formed in the insulating layer 16b. Furthermore, by irradiating the insulating layer 16c from below, through holes H1c, H2c, and H3c (first through holes) extending along the vertical axis (Z-axis) and a second through hole H10 (through hole forming process) are formed in the insulating layer 16c (first insulating layer). Furthermore, by irradiating the insulating layer 16d from above, through holes H1d, H2d, and H3d extending along the vertical axis (Z-axis) are formed in the insulating layer 16d. In the through-hole formation process, wet etching can be used instead of X-ray beam irradiation to form through-holes H1a, H2a, H3a, H1b, H2b, H3b, H1c, H2c, H3c, H1d, H2d, H3d (first through-hole) and second through-hole H10.

[0082] Next, as Figure 5 As shown, the first ground conductor layer 22 and ground conductor layers 26a, 28a, and 30a are formed by processing metal foils 122 and 126a (conductor layer formation process). In the conductor layer formation process, the metal foils 122 and 126a are etched through a mask, thereby forming the first ground conductor layer 22 and ground conductor layers 26a, 28a, and 30a.

[0083] Next, as Figure 6 As shown, conductive paste is filled into the through holes H1a, H2a, H3a, H1b, H2b, and H3b.

[0084] Next, as Figure 7 As shown, through-holes H1c, H2c, H3c, H1d, H2d, H3d (first through-holes) and the second through-hole H10 are formed using the same material as metal foils 126b and 124, respectively, forming columnar conductors v1c, v2c, v3c, v1d, v2d, v3d, and columnar conductor v10 (first and second columnar conductors) (columnar conductor forming process). In the columnar conductor forming process, an insulating layer 16d (second insulating layer) on which the columnar conductor v2d (first conductor) is provided is prepared (second preparation process).

[0085] Next, as Figure 8 As shown, conductive paste is applied above the columnar conductors v1d, v2d, and v3d.

[0086] Next, as Figure 9As shown, the second ground conductor layer 24 and ground conductor layers 26b, 28b, and 30b are formed by processing metal foils 126b and 124 (conductor layer formation process). In the conductor layer formation process, the metal foils 126b and 124 are etched through a mask, thereby forming the second ground conductor layer 24 and the ground conductor layers 26b, 28b, and 30b.

[0087] Next, as Figure 10 As shown, insulating layers 16a to 16d, which include insulating layer 16c (first insulating layer) and insulating layer 16d (second insulating layer), are stacked and pressed together, such that insulating layer 16c (first insulating layer) is positioned above insulating layer 16d (second insulating layer) (positive side of the Z-axis) (pressing process). In the pressing process, heat treatment and pressure treatment are performed.

[0088] Next, as Figure 2 As shown, protective layers 18a and 18b are formed on the laminated body 12 after pressing. After the above processes, the multilayer substrate 10 is completed.

[0089] [Effect]

[0090] In the multilayer substrate 10, the upper end of the pillar conductor v10 contacts the power conductor layer 20b. This increases the cross-sectional area of ​​the current path. Consequently, it is possible to achieve low resistance in the current path encompassing the power conductor layer 20b and the pillar conductor v10. In particular, a large current flows through the power conductor layer 20b. Therefore, the resistance through the power conductor layer 20b is reduced, thereby effectively reducing power loss in the multilayer substrate 10.

[0091] According to the multilayer substrate 10, no additional step is required to form the pillar conductor v10. More specifically, pillar conductors v1c, v2c, v3c, and pillar conductor v10 are provided in through holes that penetrate the insulating layer 16c along the upper and lower axes. Therefore, pillar conductor v10 can be formed in the steps of forming pillar conductors v1c, v2c, and v3c. Thus, according to the multilayer substrate 10, no additional step is required to form the pillar conductor v10.

[0092] The surface roughness of the lower main surface of the power conductor layer 20b is greater than that of the upper main surface of the power conductor layer 20b. However, the cylindrical conductor v10 is in contact with the lower main surface of the power conductor layer 20b. Therefore, the area of ​​the surface with the larger surface roughness in the power conductor layer 20b is reduced. As a result, a lower resistance can be achieved in the current path encompassing both the power conductor layer 20b and the cylindrical conductor v10.

[0093] The material of the pillar conductor v10 (the material of the second pillar conductor) is a resin-free metal. Therefore, the resistance of the pillar conductor v10 is reduced. Consequently, it is possible to achieve low resistance in the current path including the power conductor layer 20b and the pillar conductor v10.

[0094] The columnar conductor v10 (the second columnar conductor) has a range in which its thickness tapers as it moves upward (in the positive direction of the Z-axis). That is, the columnar conductor v10 has a conical shape. Therefore, for the following reasons, it is possible to achieve low resistance in the current path encompassing the power conductor layer 20b and the columnar conductor v10. More specifically, the width of the upper end of the columnar conductor v10 along the front-rear axis is smaller than the width of the power conductor layer 20b along the front-rear axis. This is to suppress overflow of the columnar conductor v10 from the power conductor layer 20b due to positional displacement. However, the width of the lower end of the columnar conductor v10 along the front-rear axis is not limited by the width of the power conductor layer 20b along the front-rear axis. Therefore, the width of the lower end of the columnar conductor v10 along the front-rear axis can also be larger than the width of the upper end of the columnar conductor v10 along the front-rear axis. Therefore, the volume of the cylindrical conductor v10 becomes larger than that of a cylindrical conductor with a uniform thickness. As a result, it is possible to achieve low resistance in the current path that includes the power conductor layer 20b and the cylindrical conductor v10.

[0095] The lower end face of the cylindrical conductor v10 has a downward protruding shape. As a result, the volume of the cylindrical conductor v10 increases, thus enabling the current path, which includes the power conductor layer 20b and the cylindrical conductor v10, to achieve low resistance.

[0096] (First variation)

[0097] Hereinafter, the multilayer substrate 10a according to the first modified example will be described with reference to the accompanying drawings. Figure 11 This is a cross-sectional view of the multilayer substrate 10a.

[0098] The multilayer substrate 10a differs from multilayer substrate 10 in that it also includes a pillar-shaped conductor v11 (the third pillar-shaped conductor). The upper end (the end on the positive side of the Z-axis) of the pillar-shaped conductor v11 (the third pillar-shaped conductor) contacts the power conductor layer 20b (the second conductor layer). The lower end (the end on the negative side of the Z-axis) of the pillar-shaped conductor v11 (the third pillar-shaped conductor) does not contact any conductor. Viewed in the downward direction (the negative direction of the Z-axis), the pillar-shaped conductors v10 (the second pillar-shaped conductor) and v11 (the third pillar-shaped conductor) are arranged in the linewidth direction of the power conductor layer 20b (the second conductor layer). Furthermore, the material of the pillar-shaped conductor v11 is the same as that of the pillar-shaped conductor v10. The other structures of multilayer substrate 10a are the same as those of multilayer substrate 10, and therefore descriptions are omitted. Multilayer substrate 10a can achieve the same effects as multilayer substrate 10.

[0099] The multilayer substrate 10a also includes a columnar conductor v11, thus providing a large surface area for the conductor connected to the power conductor layer 20b. As a result, the multilayer substrate 10a exhibits high heat dissipation.

[0100] (Second variation)

[0101] Hereinafter, the multilayer substrate 10b of the second modified example will be described with reference to the accompanying drawings. Figure 12 This is a cross-sectional view of the multilayer substrate 10b.

[0102] The difference between multilayer substrate 10b and multilayer substrate 10 is that the signal conductor layer 20a is the second conductor layer. Therefore, the upper end of the pillar-shaped conductor v10 is in contact with the signal conductor layer 20a. High-frequency signals with frequencies above 20 GHz are transmitted in the signal conductor layer 20a (the second conductor layer). The other structures of multilayer substrate 10b are the same as those of multilayer substrate 10, and therefore descriptions are omitted. Multilayer substrate 10b can achieve the same effects as multilayer substrate 10.

[0103] According to the multilayer substrate 10b, the transmission loss of the signal conductor layer 20a can be reduced. More specifically, high-frequency signals flow near the surface of the signal conductor layer 20a due to the skin effect. Therefore, it is preferable that the surface roughness of the signal conductor layer 20a is small. Consequently, the surface roughness of the lower main surface of the signal conductor layer 20a is greater than the surface roughness of the upper main surface of the signal conductor layer 20a. Moreover, the columnar conductor v10 is in contact with the lower main surface of the signal conductor layer 20a. As a result, the number of surfaces with large surface roughness in the signal conductor layer 20a is reduced. Consequently, the transmission loss of the signal conductor layer 20a can be reduced.

[0104] (3rd variation)

[0105] Hereinafter, the multilayer substrate 10c involved in the third modified example will be described with reference to the accompanying drawings. Figure 13This is a top view of the insulating layer 16c of the multilayer substrate 10c.

[0106] The multilayer substrate 10c differs from the multilayer substrate 10 in the shape of the power conductor layer 20b and the shape of the pillar conductor v10. More specifically, the multilayer substrate 10c has a first interval A1a, A1b in which the power conductor layer 20b (the second conductor layer) has first line widths w1a, w1b, and a second interval A2a, A2b in which the power conductor layer 20b (the second conductor layer) has a second line width w2 that is larger than the first line widths w1a, w1b. The first line width w1a is larger than the first line width w1b. The second line width w2 is the maximum value of the line width of the power conductor layer 20b (the second conductor layer). Furthermore, the pillar conductor v10 is provided in the first intervals A1a, A1b. The pillar conductor v10 (the second pillar conductor) is not provided in the second intervals A2a, A2b. The other structures of the multilayer substrate 10c are the same as those of the multilayer substrate 10, and therefore, descriptions are omitted. The multilayer substrate 10c can achieve the same effects as the multilayer substrate 10.

[0107] In the multilayer substrate 10c, the resistance of the power conductor layer 20b tends to be high in the first intervals A1a and A1b. Therefore, the pillar conductor v10 is provided in the first intervals A1a and A1b. As a result, in the multilayer substrate 10c, it is possible to achieve low resistance in the current path including the power conductor layer 20b and the pillar conductor v10.

[0108] (4th variation)

[0109] Hereinafter, the multilayer substrate 10d involved in the fourth modified example will be described with reference to the accompanying drawings. Figure 14 This is a top view of the insulating layer 16c of the multilayer substrate 10d. Figure 15 This is a rear view of the multilayer substrate 10d in use.

[0110] The multilayer substrate 10d differs from multilayer substrate 10 in that the columnar conductor v10 is not disposed in a portion of the interval. More specifically, multilayer substrate 10d has a third interval A3 and a fourth interval A4. Viewed in the forward direction (the positive direction of the Y-axis orthogonal to the Z-axis), the third interval A3 is curved. The columnar conductor v10 (the second columnar conductor) is not disposed in the third interval A3. The other structures of multilayer substrate 10d are the same as those of multilayer substrate 10, and therefore descriptions are omitted. Multilayer substrate 10d can achieve the same effects as multilayer substrate 10.

[0111] According to the multilayer substrate 10d, since the columnar conductor v10 is not provided in the third interval A3, the third interval A3 can be easily bent.

[0112] (5th variation)

[0113] Hereinafter, the multilayer substrate 10e according to the fifth modified example will be described with reference to the accompanying drawings. Figure 16 This is a top view of the insulating layer 16c of the multilayer substrate 10e. Regarding the rear view of the multilayer substrate 10e in use, see reference [reference missing]. Figure 15 .

[0114] The multilayer substrate 10e differs from multilayer substrate 10 in that the columnar conductor v10 is not disposed in a portion of the interval. More specifically, multilayer substrate 10e has a third interval A3 and a fourth interval A4. Viewed in the forward direction (the positive direction of the Y-axis orthogonal to the Z-axis), the third interval A3 is curved. The columnar conductor v10 (the second columnar conductor) is disposed in the third interval A3. The other structures of multilayer substrate 10e are the same as those of multilayer substrate 10, and therefore descriptions are omitted. Multilayer substrate 10e can achieve the same effects as multilayer substrate 10.

[0115] According to the multilayer substrate 10d, a columnar conductor v10 is disposed in the third section A3. If the third section A3 is bent, the columnar conductor v10 undergoes plastic deformation. As a result, it is easy to maintain the bent state of the third section A3.

[0116] (Other implementation methods)

[0117] The multilayer substrates involved in this utility model are not limited to multilayer substrates 10, 10a to 10e, and can be modified within the scope of its main idea. In addition, the structures of multilayer substrates 10, 10a to 10e can be arbitrarily combined.

[0118] In addition, protective layers 18a and 18b are not essential components.

[0119] Alternatively, the first conductor can also be a conductor layer.

[0120] Alternatively, multiple small columnar conductors v10 may be arranged along the power conductor layer 20b.

[0121] Alternatively, the insulating layers 16a to 16d can also be made of ceramic.

[0122] In addition, the columnar conductor v10 may have a portion in which the thickness of the columnar conductor v10 decreases as it moves upward, or the thickness of the columnar conductor v10 may decrease as it moves upward in the whole.

[0123] Furthermore, the materials of the multiple columnar conductors v1c, v2c, and v3c (the materials of the first and second columnar conductors) can all be the same. Therefore, the materials of the multiple columnar conductors v1c, v2c, and v3c can also be different from the materials of the signal conductor layer 20a, power conductor layer 20b, first ground conductor layer 22, second ground conductor layer 24, ground conductor layers 26a, 26b, 28a, 28b, 30a, 30b, multiple columnar conductors v1d, v2d, and v3d.

[0124] In addition, Figure 13 In the first interval A1b, the width of the laminate 12 along the front-rear axis can also be smaller than the width of the laminate 12 along the front-rear axis in the first interval A1a.

[0125] Additionally, the lower end of the cylindrical conductor v1c can also contact the cylindrical conductor v1d located below it. That is, contact is a subordinate concept to connection.

[0126] Additionally, for example, in Figure 2 In the example shown, the connecting conductors v11d to v13d are located within the through-hole of the insulating layer 16d, but the connecting conductors v11d to v13d can also be located within the through-hole of the insulating layer 16c. That is, the connecting conductors can be located either at the connection destination or the connection source.

[0127] In addition, Figure 2 In the example shown, columnar conductors v1c, v2c, v3c and columnar conductors v1d, v2d, v3d are connected via connecting conductors v11d, v12d, v13d, respectively. However, this invention is not limited to connecting the columnar conductors to each other. For example, columnar conductors v1c, v2c, v3c can also be connected to a conductor layer made of metal foil such as copper foil. In this case, the columnar conductors v1c, v2c, v3c are connected to the conductor layer via connecting conductors v11d, v12d, v13d.

[0128] The multilayer substrate involved in this utility model has the following structure. (1)

[0130] A multilayer substrate, wherein,

[0131] It comprises at least a laminate, a first conductor layer, a second conductor layer, a first columnar conductor, a second columnar conductor, and a connecting conductor.

[0132] The laminate has a structure in which multiple insulating layers, including a first insulating layer, are stacked along the Z-axis.

[0133] The first insulating layer has a positive principal surface and a negative principal surface located on the negative side of the Z-axis, which is closer to the positive principal surface.

[0134] The first conductor layer and the second conductor layer are located on the positive principal plane of the first insulator layer.

[0135] The first columnar conductor and the second columnar conductor are disposed inside the through hole that penetrates the first insulating layer along the Z-axis.

[0136] The end of the first columnar conductor on the positive side of the Z-axis is in contact with the first conductor layer.

[0137] The connecting conductor is a conductor that electrically connects the conductors in the stacked direction.

[0138] The negative end of the first columnar conductor on the Z-axis is connected to the columnar conductor or conductor layer via the connecting conductor.

[0139] The end of the second columnar conductor on the positive side of the Z-axis is in contact with the second conductor layer.

[0140] The end of the second cylindrical conductor on the negative side of the Z-axis does not contact any other conductor.

[0141] The first columnar conductor and the second columnar conductor are made of the same material.

[0142] The material of the connecting conductor is different from the materials of the first columnar conductor and the second columnar conductor.

[0143] The material of the connecting conductor is a mixture or alloy of resin and metal. (2)

[0145] According to the multilayer substrate described in (1), wherein,

[0146] The materials of the first columnar conductor and the second columnar conductor are metals that do not contain resin. (3)

[0148] According to the multilayer substrate described in (1) or (2), wherein,

[0149] The first columnar conductor has a range in which the thickness of the first columnar conductor decreases as it moves toward the positive direction of the Z-axis.

[0150] The second columnar conductor has a range in which the thickness of the second columnar conductor decreases as it moves toward the positive direction of the Z-axis. (4)

[0152] The multilayer substrate according to any one of (1) to (3), wherein,

[0153] The end face of the second columnar conductor on the negative side of the Z-axis has a shape that protrudes in the negative direction of the Z-axis. (5)

[0155] The multilayer substrate according to any one of (1) to (4), wherein,

[0156] Viewed in the negative direction of the Z-axis, the second conductor layer has a linear shape. (6)

[0158] According to the multilayer substrate described in (5), wherein,

[0159] The multilayer substrate also includes a third columnar conductor.

[0160] The end of the third columnar conductor on the positive side of the Z-axis is in contact with the second conductor layer.

[0161] The end of the third columnar conductor on the negative side of the Z-axis does not contact any other conductor.

[0162] Viewed in the negative direction of the Z-axis, the second and third columnar conductors are arranged in the linewidth direction of the second conductor layer.

[0163] The material of the second columnar conductor is the same as that of the third columnar conductor. (7)

[0165] According to the multilayer substrate described in (5) or (6), wherein,

[0166] The multilayer substrate has:

[0167] The first interval, wherein the second conductor layer has a first linewidth; and

[0168] In the second interval, the second conductor layer has a second line width that is larger than the first line width.

[0169] The second line width is the maximum value of the line width of the second conductor layer.

[0170] The second columnar conductor is disposed in the first interval.

[0171] The second columnar conductor is not located in the second interval. (8)

[0173] According to the multilayer substrate described in (5) or (6), wherein,

[0174] The multilayer substrate has a third section and a fourth section.

[0175] Viewed along the positive direction of the Y-axis, which is orthogonal to the Z-axis, the third interval is curved.

[0176] The second columnar conductor is not located in the third interval. (9)

[0178] According to the multilayer substrate described in (5) or (6), wherein,

[0179] The multilayer substrate has a third section and a fourth section.

[0180] Viewed along the positive direction of the Y-axis, which is orthogonal to the Z-axis, the third interval is curved.

[0181] The second columnar conductor is disposed in the third interval. (10)

[0183] The multilayer substrate according to any one of (1) to (9), wherein,

[0184] The multilayer substrate also includes a third conductor layer and a fourth columnar conductor that penetrates the first insulating layer along the Z-axis.

[0185] The third conductor layer is located on the positive principal plane of the first insulator layer.

[0186] The end of the fourth columnar conductor on the positive side of the Z-axis is not connected to the third conductor layer.

[0187] The end of the fourth columnar conductor on the negative side of the Z-axis does not contact any conductor. (11)

[0189] The multilayer substrate according to any one of (1) to (10), wherein,

[0190] The second conductor layer has a positive principal plane and a negative principal plane located on the negative side of the Z-axis, which is closer to the positive principal plane of the second conductor layer.

[0191] The surface roughness of the negative principal surface of the second conductor layer is greater than the surface roughness of the positive principal surface of the second conductor layer. (12)

[0193] According to the multilayer substrate described in (11), wherein,

[0194] It features a signal conductor layer for transmitting high-frequency signals with frequencies above 20 GHz. (13)

[0196] The multilayer substrate according to any one of (1) to (12), wherein,

[0197] The materials of the first conductor layer, the second conductor layer, the first columnar conductor, and the second columnar conductor are the same. (14)

[0199] A method for manufacturing a multilayer substrate includes a first preparation step, a through-hole formation step, a conductor layer formation step, a pillar conductor formation step, a second preparation step, and a pressing step, wherein...

[0200] In the first preparation step, a first insulating layer is prepared, the first insulating layer having a positive principal surface and a negative principal surface located on the negative side of the positive principal surface closer to the Z-axis, and a metal foil covering the positive principal surface is provided.

[0201] In the through-hole forming process, a first through-hole and a second through-hole are formed along the Z-axis in the first insulating layer.

[0202] In the conductor layer formation process, the first conductor layer and the second conductor layer are formed by processing the metal foil.

[0203] In the columnar conductor forming process, a first columnar conductor and a second columnar conductor are formed in the first through hole and the second through hole, respectively.

[0204] In the second preparation step, a second insulating layer with a connecting conductor is prepared.

[0205] In the pressing process, multiple insulating layers, including the first insulating layer and the second insulating layer, are stacked and pressed together, such that the first insulating layer is located on the positive side of the Z-axis closer than the second insulating layer.

[0206] The end of the first columnar conductor on the positive side of the Z-axis is in contact with the first conductor layer.

[0207] The end of the second columnar conductor on the positive side of the Z-axis is in contact with the second conductor layer.

[0208] The end of the first columnar conductor on the negative side of the Z-axis is connected to the connecting conductor. (15)

[0210] According to the manufacturing method of the multilayer substrate described in (14), wherein,

[0211] In the through-hole forming process, the first through-hole and the second through-hole are formed by irradiation with a X-ray beam or by wet etching.

[0212] Explanation of reference numerals in the attached figures

[0213] 10, 10a~10e: Multilayer substrate;

[0214] 12: Layered body;

[0215] 16a~16d: Insulating layer;

[0216] 16c: First insulating layer;

[0217] 16d: Second insulating layer;

[0218] 18a, 18b: Protective layers;

[0219] 20a: Signal conductor layer;

[0220] 20b: Power conductor layer (second conductor layer);

[0221] 22: First grounding conductor layer;

[0222] 24: Second grounding conductor layer;

[0223] 26a, 26b, 28a, 28b, 30a, 30b: Grounding conductor layer;

[0224] 26b, 28b, 30b: Grounding conductor layer (first conductor layer);

[0225] A1a, A1b: The first interval;

[0226] A2a: The second interval;

[0227] A3: The third interval;

[0228] A4: The 4th interval;

[0229] H10: Second through hole;

[0230] H1a~H1d: Through holes;

[0231] v1a~v1d, v2a~v2d, v3a~v3d, v10, v11: columnar conductors;

[0232] v1c, v2c, v3c, v1d, v2d, v3d: cylindrical conductors (first cylindrical conductor);

[0233] v10: Pillar conductor (second pillar conductor);

[0234] v11: Pillar conductor (3rd pillar conductor);

[0235] v11d, v12d, v13d: Connecting conductors.

Claims

1. A multilayer substrate characterized by comprising: at least a laminate, a first conductor layer, a second conductor layer, a first columnar conductor, a second columnar conductor, and a connection conductor, the laminate has a configuration in which a plurality of insulator layers including a first insulator layer are stacked along a Z axis, the first insulator layer has a positive main surface and a negative main surface located on a negative side of the Z axis from the positive main surface, the first conductor layer and the second conductor layer are located on the positive main surface of the first insulator layer, the first columnar conductor and the second columnar conductor are provided inside a through-hole that penetrates the first insulator layer along the Z axis, an end portion of the first columnar conductor on a positive side of the Z axis is in contact with the first conductor layer, the connection conductor is a conductor that electrically connects conductors in the stacking direction, an end portion of the first columnar conductor on a negative side of the Z axis is connected to a columnar conductor or a conductor layer via the connection conductor, an end portion of the second columnar conductor on a positive side of the Z axis is in contact with the second conductor layer, an end portion of the second columnar conductor on a negative side of the Z axis is not in contact with any conductor, a material of the first columnar conductor and a material of the second columnar conductor are the same material, a material of the connection conductor is different from materials of the first columnar conductor and the second columnar conductor, the material of the connection conductor is a mixture or an alloy of resin and metal.

2. The multilayer substrate according to claim 1, characterized in that: the material of the first columnar conductor and the material of the second columnar conductor are metals that do not contain resin.

3. The multilayer substrate according to claim 1 or 2, characterized in that: the first columnar conductor has an interval in which a thickness of the first columnar conductor becomes thinner as it advances in a positive direction of the Z axis, the second columnar conductor has an interval in which a thickness of the second columnar conductor becomes thinner as it advances in the positive direction of the Z axis.

4. The multilayer substrate according to claim 1 or 2, characterized in that: an end surface of the second columnar conductor on the negative side of the Z axis has a shape that protrudes in a negative direction of the Z axis.

5. The multilayer substrate according to claim 1 or 2, characterized in that: the second conductor layer has a linear shape as viewed in a negative direction of the Z axis.

6. The multilayer substrate according to claim 5, characterized in that: the multilayer substrate further comprises a third columnar conductor, an end portion of the third columnar conductor on a positive side of the Z axis is in contact with the second conductor layer, an end portion of the third columnar conductor on a negative side of the Z axis is not in contact with any conductor, the second columnar conductor and the third columnar conductor are arranged in a line width direction of the second conductor layer as viewed in the negative direction of the Z axis, a material of the second columnar conductor is the same as a material of the third columnar conductor.

7. The multilayer substrate according to claim 5, characterized in that: the multilayer substrate has: a first interval in which the second conductor layer has a first line width; and a second interval in which the second conductor layer has a second line width that is larger than the first line width. The second line width is a maximum value of line widths of the second conductor layer, The second columnar conductor is provided in the first section, The second columnar conductor is not provided in the second section.

8. The multilayer substrate according to claim 5, wherein The multilayer substrate has a third section and a fourth section, The third section is curved as viewed in a positive direction of a Y axis orthogonal to the Z axis, The second columnar conductor is not provided in the third section.

9. The multilayer substrate according to claim 5, wherein The multilayer substrate has a third section and a fourth section, The third section is curved as viewed in a positive direction of a Y axis orthogonal to the Z axis, The second columnar conductor is provided in the third section.

10. The multilayer substrate according to claim 1 or 2, wherein The multilayer substrate further has a third conductor layer and a fourth columnar conductor that penetrates the first insulator layer along the Z axis, The third conductor layer is located at the positive main surface of the first insulator layer, An end portion of the fourth columnar conductor on the positive side of the Z axis is not connected to the third conductor layer, An end portion of the fourth columnar conductor on the negative side of the Z axis does not contact any conductor.

11. The multilayer substrate according to claim 1 or 2, wherein The second conductor layer has a positive main surface and a negative main surface located on the negative side of the Z axis than the positive main surface of the second conductor layer, A surface roughness of the negative main surface of the second conductor layer is greater than a surface roughness of the positive main surface of the second conductor layer.

12. The multilayer substrate according to claim 1 or 2, wherein A signal conductor layer that transmits a high-frequency signal having a frequency of 20 GHz or more is provided.

13. The multilayer substrate according to claim 1 or 2, wherein The material of the first conductor layer, the material of the second conductor layer, the material of the first columnar conductor, and the material of the second columnar conductor are the same material.

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