Coaxial through-hole structure and its manufacturing method

Abstract

The present invention is a coaxial through-hole structure and a manufacturing method thereof. The coaxial through-hole structure includes a substrate, a first conductive structure, a second conductive structure, and an insulating layer. The substrate has a first surface. The first conductive structure includes a first circuit located on the first surface and a first through-hole penetrating the substrate. The second conductive structure includes a second circuit located on the first surface of the substrate and a second through-hole penetrating the substrate. The first through-hole and the second through-hole extend in a first direction, the first circuit and the second circuit extend in a second direction, and the second direction is perpendicular to the first direction. The insulating layer is located between the first through-hole and the second through-hole, the first conductive structure and the second conductive structure are electrically insulated, and the first circuit and the second circuit are coplanar. The coaxial through-hole structure can have better electromagnetic noise shielding and impedance matching effects to improve the integrity of high-frequency signals. In addition, the coaxial through-hole structure can reduce the number of dielectric layers to reduce the thickness of the coaxial through-hole structure, having the technical effect of reducing costs.

Description

Technical Field

[0001] The present disclosure relates to a coaxial via structure, and more particularly to a coaxial via structure having coplanar signal lines and ground lines. Background Art

[0002] Most of the current coaxial via structures need to set dielectric layers between ground lines and signal lines on different layers through a lamination build-up process, which consumes more costs. In addition, due to the different heights of the inner layer lines and the outer layer lines in the via holes, impedance mismatch problems will occur. The dielectric layers disposed between the ground lines and the signal lines will also generate shielding gaps, resulting in poor electromagnetic shielding effects.

[0003] In view of this, how to provide a coaxial via structure that can improve impedance matching and electromagnetic shielding effects is still one of the goals that the industry urgently needs to study currently. Summary of the Invention

[0004] One technical aspect of the present disclosure is a coaxial via structure.

[0005] In an embodiment of the present disclosure, the coaxial via structure includes a substrate, a first conductive structure, a second conductive structure, and an insulating layer. The substrate has a first surface. The first conductive structure includes a first line on the first surface and a first via hole penetrating the substrate. The second conductive structure includes a second line on the first surface of the substrate and a second via hole penetrating the substrate. The first via hole and the second via hole extend in a first direction, the first line and the second line extend in a second direction, and the second direction is perpendicular to the first direction. The insulating layer is located between the first via hole and the second via hole, wherein the first conductive structure and the second conductive structure are electrically insulated, and the first line and the second line are coplanar.

[0006] In an embodiment of the present disclosure, the first via hole of the first conductive structure surrounds the second via hole of the second conductive structure and the insulating layer.

[0007] In an embodiment of the present disclosure, the insulating layer, the first via hole, and the second via hole are coaxial.

[0008] In an embodiment of the present disclosure, the insulating layer has a protruding portion located at the end of the insulating layer close to the first surface.

[0009] In an embodiment of the present disclosure, the protruding portion of the insulating layer protrudes away from the second via hole along the second direction.

[0010] In an embodiment of the present disclosure, the first via hole of the first conductive structure, the protruding portion of the insulating layer, and the second line of the second conductive structure overlap in the first direction.

[0011] In an embodiment of the present disclosure, the substrate further includes a second surface opposite to the first surface, and the coaxial via structure further includes a dielectric layer located between the first surface and the second surface, and the protruding portion of the insulating layer contacts the dielectric layer.

[0012] One technical aspect of the present disclosure is a manufacturing method of a coaxial via structure.

[0013] In an embodiment of the present disclosure, the manufacturing method of the coaxial via structure includes forming a first through hole in the substrate; forming a first conductive material on the first surface of the substrate and in the first through hole; forming a groove recessed from the first surface and communicating the groove with the first through hole; forming an insulating layer in the first through hole and the groove; forming a second conductive material on the first surface of the substrate and in the first through hole; and patterning the first conductive material and the second conductive material to form a first line and a second line on the first surface, such that the remaining first conductive material and the remaining second conductive material are electrically insulated by the insulating layer in the groove, and the first line and the second line are coplanar.

[0014] In an embodiment of the present disclosure, the coaxial via structure further includes a second surface opposite to the first surface, and forming the groove further includes drilling a hole from the first surface along a first direction.

[0015] In an embodiment of the present disclosure, the coaxial via structure further includes a dielectric layer located between the first surface and the second surface, and forming the groove further includes exposing the dielectric layer from the first conductive material.

[0016] In an embodiment of the present disclosure, forming the insulating layer in the first through hole and the groove further includes forming an insulating layer material in the first through hole and the groove such that the insulating layer material contacts the dielectric layer; and forming a second through hole in the insulating layer material to form the insulating layer, wherein the insulating layer has a protruding portion located in the groove.

[0017] In an embodiment of the present disclosure, forming the second conductive material on the first surface of the substrate and in the first through hole further includes forming the second conductive material in the second through hole and surrounding the insulating layer and the second conductive material in the second through hole with the first conductive material in the first through hole.

[0018] In an embodiment of the present disclosure, forming the second conductive material on the first surface of the substrate and in the first through hole further includes making the insulating layer, the first conductive material in the first through hole, and the second conductive material in the second through hole coaxial.

[0019] In an embodiment of the present disclosure, patterning the first conductive material and the second conductive material to form the first line and the second line further includes making the first conductive material in the first through hole, the protruding portion of the insulating layer, and the second line overlap in the first direction.

[0020] In the above embodiments, since the coaxial via structure of the present disclosure has coplanar first and second circuits, and the first and second conductive structures can be electrically insulated by the insulating layer, the coaxial via structure of the present disclosure can have better electromagnetic noise shielding and impedance matching effects to improve high-frequency signal integrity. In addition, the coaxial via structure of the present disclosure can reduce the number of dielectric layers to reduce the thickness of the coaxial via structure. Therefore, the coaxial via structure of the present disclosure can also have the technical effect of cost reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 FIG. 6 is a perspective view of a coaxial via structure according to an embodiment of the present disclosure.

[0022] Figure 2 FIG. 7 is a sectional view taken along line 2-2 in Figure 1 FIG. 6.

[0023] Figures 3A to 11A FIG. 8 is a top view of an intermediate step of a manufacturing method of a coaxial via structure according to an embodiment of the present disclosure.

[0024] Figures 3B to 11B FIGS. 9 to 11 are sectional views taken along lines 3B-3B to 11B-11B in Figures 3A to 11A FIG. 8, respectively.

[0025]

MAIN ELEMENT SYMBOL DESCRIPTION

[0026] 100: Coaxial via structure 110: Substrate

[0027] 112: First surface 114: Second surface

[0028] 116: Internal circuit 120: First conductive structure

[0029] 120M: First conductive material 122: First circuit

[0030] 124: First via 126: Third circuit

[0031] 130: Second conductive structure 130M: Second conductive material

[0032] 132: Second circuit 134: Second via

[0033] 136: Fourth circuit 140: Insulating layer

[0034] 140M: Insulating layer material 142: First protrusion

[0035] 144: Second protrusion 150: Dielectric layer

[0036] 160: Photomask 170: Insulating protective layer

[0037] D1: First direction; D2: Second direction

[0038] OP1: First through hole; OP2: Second through hole

[0039] TR1: First groove; TR2: Second groove

[0040] A: Axis

[0041] 3B-3B, 4B-4B, 5B-5B, 6B-6B, 7B-7B, 8B-8B, 9B-9B, 10B-10B, 11B-11B: Line segments

[0042] W1, W2: Width; I: Spacing Detailed implementation manners

[0043] Multiple implementation manners of the present invention will be disclosed below with reference to the drawings. For the sake of clear illustration, many practical details will be described together in the following description. However, it should be understood that these practical details are not used to limit the present invention. That is to say, in some implementation manners of the present invention, these practical details are not necessary. In addition, for the purpose of simplifying the drawings, some conventional structures and elements in the prior art will be shown in a simple schematic manner in the drawings. And for the sake of clarity, the thickness of the layers and regions in the drawings may be exaggerated, and the same reference numerals in the description of the drawings represent the same elements.

[0044] Figure 1 Is a perspective view of a coaxial through-hole structure 100 according to an embodiment of the present disclosure. Figure 2 Is along Figure 1 The sectional view of the line segment 2-2 in. At the same time, refer to Figure 1 And Figure 2 . The coaxial through-hole structure 100 includes a substrate 110, a first conductive structure 120, a second conductive structure 130 and an insulating layer 140.

[0045] The substrate 110 has opposite first surface 112 and second surface 114. The first conductive structure 120 includes a first line 122 and a first through hole 124, and the second conductive structure 130 includes a second line 132 and a second through hole 134. The first line 122 and the second line 132 are located on the first surface 112. The first through hole 124 and the second through hole 134 penetrate through the substrate 110. The first through hole 124 and the second through hole 134 extend in the first direction D1. The first line 122 and the second line 132 extend in the second direction D2 perpendicular to the first direction D1. The first line 122 of the first conductive structure 120 and the second line 132 of the second conductive structure 130 are coplanar. In other words, the first line 122 and the second line 132 are located on the same horizontal plane.

[0046] In this embodiment, the first direction D1 is the vertical direction in the figure, that is, the first direction D1 is the direction from the first surface 112 towards the second surface 114. The second direction D2 can be any horizontal direction perpendicular to the first direction D1, which is stated first for clarity. In this embodiment, the first line 122 and the third line 126 can be ground lines, and the second line 132 and the fourth line 136 can be signal lines, but the present disclosure is not limited thereto.

[0047] As Figure 2 shown, the first conductive structure 120 further includes a third line 126 located on the second surface 114, and the second conductive structure 130 further includes a fourth line 136 located on the second surface 114. The two ends of the first via 124 are respectively connected to the first line 122 and the third line 126. The two ends of the second via 134 are respectively connected to the second line 132 and the fourth line 136. The third line 126 and the fourth line 136 extend in the second direction D2, and the third line 126 and the fourth line 136 are coplanar. In other words, the third line 126 and the fourth line 136 are located on the same horizontal plane.

[0048] The insulating layer 140 is located between the first via 124 and the second via 134, and the insulating layer 140 extends in the first direction D1. The first via 124 surrounds the second via 134 and the insulating layer 140, and the insulating layer 140 surrounds the second via 134. As Figure 2 shown, the insulating layer 140, the first via 124, and the second via 134 are coaxial with respect to the axis A.

[0049] The insulating layer 140 has a first protrusion 142, and the first protrusion 142 is located at the end of the insulating layer 140 close to the first surface 112. The first protrusion 142 protrudes away from the second via 134 along the second direction D2. As Figure 2 shown, the substrate 110 further includes a dielectric layer 150 located between the first surface 112 and the second surface 114. In this embodiment, the substrate 110 further includes multiple internal lines 116 separated by the dielectric layer 150, but the present disclosure is not limited thereto. The first protrusion 142 of the insulating layer 140 contacts the dielectric layer 150 close to the first surface 112. In other words, the first protrusion 142 passes through the first via 124 and extends to the dielectric layer 150.

[0050] It should be understood that in order to clearly show the structural relationship between the second line 132 and the first protrusion 142, only the first via 124, the second line 132, and the insulating layer 140 are shown in Figure 1 , and the first line 122 is omitted.

[0051] As Figure 2As shown, the first through hole 124 of the first conductive structure 120, the first protrusion 142 of the insulating layer 140, and the second circuit 132 of the second conductive structure 130 overlap in the first direction D1. The second circuit 132 of the second conductive structure 130 extends from the second through hole 134 and crosses the first protrusion 142. In other words, the first through hole 124 and the second circuit 132 are electrically insulated by the first protrusion 142, and the coplanar first circuit 122 and the second circuit 132 are separated from each other, thereby making the first conductive structure 120 and the second conductive structure 130 electrically insulated.

[0052] According to the above, since the first circuit 122 and the second circuit 132 of the coaxial through-hole structure 100 are coplanar, and the first conductive structure 120 and the second conductive structure 130 are electrically insulated, the step of adding an additional dielectric layer to electrically insulate the first circuit and the second circuit located at different layers can be omitted. In this way, the first through-hole 124 and the second through-hole 134 of the present case can have roughly the same height, so that the overall structure of the coaxial through-hole structure 100 is more symmetrical, thereby improving the impedance matching effect. In addition, since the dielectric layer between the first circuit and the second circuit located at different layers can be omitted in the present case, the situation where the second through-hole 134 protrudes outside the insulating layer is avoided. In this way, the coaxial through-hole structure of the present case can avoid the problem of poor electromagnetic shielding effect caused by the gap of the shielding structure.

[0053] like Figure 2 As shown, the insulating layer 140 further has a second protrusion 144, and the second protrusion 144 is located at the end of the insulating layer 140 close to the second surface 114. The second protrusion 144 protrudes away from the second through hole 134 along the second direction D2. The second protrusion 144 of the insulating layer 140 contacts the dielectric layer 150 close to the second surface 114. In other words, the second protrusion 144 passes through the first through hole 124 and extends to the dielectric layer 150.

[0054] like Figure 2 As shown, the first through hole 124 of the first conductive structure 120, the second protrusion 144 of the insulating layer 140, and the fourth line 136 of the second conductive structure 130 overlap in the first direction D1. The fourth line 136 of the second conductive structure 130 extends from the second through hole 134 and crosses the second protrusion 144. In other words, the first through hole 124 and the fourth line 136 are electrically insulated by the second protrusion 144, and the third line 126 and the fourth line 136 are separated from each other, thereby making the first conductive structure 120 and the second conductive structure 130 electrically insulated. As mentioned above, the extension direction of the fourth line 136 can be any horizontal direction perpendicular to the first direction D1, Figure 2 This is only an example, and the present disclosure is not limited thereto.

[0055] It should be understood that the component connection relationships, materials, and functions described above will not be repeated here for the sake of brevity. In the following description, a manufacturing method for a coaxial through-hole structure will be described.

[0056] Figures 3A to 10A It is a top view of an intermediate step of a manufacturing method for a coaxial through-hole structure according to an embodiment of the present disclosure. Figures 3B to 10B Respectively are cross-sectional views along Figures 3A to 10B the line segment 3B - 3B to the line segment 10B - 10B in Figure 3A and Figure 3B As shown, the manufacturing method of the coaxial through-hole structure begins with forming a first through-hole OP1 in the substrate 110. The first through-hole OP1 penetrates the internal circuit 116 and the dielectric layer 150 of the substrate 110. For example, the way to form the first through-hole OP1 can be laser drilling.

[0057] As Figure 4A and Figure 4B shown, in the manufacturing method of the coaxial through-hole structure, then a first conductive material 120M is formed on the first surface 112, the second surface 114, and the inner wall of the first through-hole OP1. The way to form the first conductive material 120M is, for example, electroplating, and the first conductive material 120M is, for example, copper, but the present disclosure is not limited thereto, and those skilled in the art can select appropriate methods and materials according to the situation.

[0058] As Figure 5A and Figure 5B shown, in the manufacturing method of the coaxial through-hole structure, then a first groove TR1 is formed. The first groove TR1 is recessed from the first surface 112, and the first groove TR1 communicates with the first through-hole OP1. The way to form the first groove TR1 includes drilling from the first surface 112 along the first direction D1, and exposing the dielectric layer 150 near the first surface 112 from the first conductive material 120M.

[0059] Referring to Figure 5B , this step also includes forming a second groove TR2. The second groove TR2 is recessed from the second surface 114, and the second groove TR2 communicates with the first through-hole OP1. The way to form the second groove TR2 includes drilling from the second surface 114 along the opposite direction of the first direction D1, and exposing the dielectric layer 150 near the second surface 114 from the first conductive material 120M. For example, the way to form the first groove TR1 and the second groove TR2 can be laser drilling.

[0060] In Figure 5AIn the top-down view, the distance between the first groove TR1 and the first through-hole OP1 can be calculated based on the width of the second line 132 and the required spacing between the first line 122 and the second line 132. Similarly, in the bottom-up view (not shown in the figure), the distance between the second groove TR2 and the first through-hole OP1 can be calculated based on the width of the fourth line 136 and the required spacing between the third line 126 and the fourth line 136.

[0061] As Figure 6A and Figure 6B shown, in the manufacturing method of the coaxial through-hole structure, then the insulating layer material 140M is filled into the first through-hole OP1, the first groove TR1 and the second groove TR2, and the insulating layer material 140M is made to contact the dielectric layer 150 exposed from the first conductive material 120M. In this embodiment, the insulating layer material 140M can be, for example, via-fill ink, but the present disclosure is not limited thereto. After filling the insulating layer material 140M, the portions of the insulating layer material 140M exposed from the first surface 112 and the second surface 114 are ground, so that the upper surface and the lower surface of the insulating layer 140 are flush with the first conductive material 120M respectively.

[0062] As Figure 7A and Figure 7B shown, in the manufacturing method of the coaxial through-hole structure, then a second through-hole OP2 is formed in the insulating layer material 140M. In this embodiment, the second through-hole OP2 and the first through-hole OP1 are concentric circles. For example, the second through-hole OP2 is formed by laser drilling, thereby removing a part of the insulating layer material 140M. After forming the second through-hole OP2, the remaining insulating layer material 140M includes the portion located in the first through-hole OP1 (i.e., the insulating layer 140) and the first protrusion 142 and the second protrusion 144 located on both sides of the substrate 110 respectively.

[0063] As Figure 8A and Figure 8B shown, in the manufacturing method of the coaxial through-hole structure, then the second conductive material 130M is formed on the first surface 112, on the second surface 114 and in the second through-hole OP2. The first conductive material 120M can be formed, for example, by electroplating, and the first conductive material 120M is, for example, copper, but the present disclosure is not limited thereto, and those skilled in the art can select appropriate methods and materials according to the situation.

[0064] The second conductive material 130M is located in the second via hole OP2, and the first conductive material 120M (i.e., the first through hole 124) in the first via hole OP1 surrounds the insulating layer 140 and the second conductive material 130M (i.e., the second through hole 134) in the second via hole OP2, such that the insulating layer 140, the first conductive material 120M in the first via hole OP1, and the second conductive material 130M in the second via hole OP2 are coaxial with respect to the axis A.

[0065] As Figure 9A and Figure 9B shown, in the manufacturing method of the coaxial via structure, a photomask 160 is then formed on the first surface 112 and the second surface 114. The photomask 160 includes patterns for forming the first circuit 122 and the second circuit 132, and patterns for forming the third circuit 126 and the fourth circuit 136.

[0066] As Figure 10A and Figure 10B shown, in the manufacturing method of the coaxial via structure, the first conductive material 120M and the second conductive material 130M are then patterned by the photomask 160. The second conductive material 130M and the first conductive material 120M exposed from the photomask 160 are successively removed until the insulating layer 140 and the dielectric layer 150 are exposed from the photomask 160.

[0067] Referring simultaneously to Figure 10A , Figure 10B , Figure 11A and Figure 11B . In the manufacturing method of the coaxial via structure, finally, the photomask 160 is removed, and an insulating protective layer 170 is formed. The insulating protective layer 170 has an opening for connecting conductive elements, such as metal bumps, studs, or solder balls (not shown in the figure).

[0068] As Figure 11B shown, after the above steps, the first circuit 122 and the second circuit 132 separated from each other can be formed, and the first circuit 122 and the second circuit 132 are coplanar. The first through hole 124 and the second circuit 132 are electrically insulated by the first protrusion 142 in the first groove TR1. The first circuit 122 can include any circuit pattern as long as the first circuit 122 and the second circuit 132 are electrically insulated.

[0069] Similarly, after the above steps, the third circuit 126 and the fourth circuit 136 separated from each other can be formed, and the third circuit 126 and the fourth circuit 136 are coplanar. The first through hole 124 and the fourth circuit 136 are electrically insulated by the second protrusion 144 in the second groove TR2. The third circuit 126 can include any circuit pattern (not shown in the figure) as long as the third circuit 126 and the fourth circuit 136 are electrically insulated.

[0070] Referring toFigure 11A In this embodiment, the second line 132 has a width W1, and the connection between the insulating layer 140 and the first protrusion 142 has a width W2. The width W2 can be correspondingly adjusted by changing the distance between the first groove TR1 and the first through hole OP1, and the width W2 can also depend on the aperture of the first groove TR1. Therefore, according to the required width W1, the appropriate distance between the first groove TR1 and the first through hole OP1 can be calculated in the step of forming the first groove TR1. In this way, it can be ensured that the width W2 is wide enough to reduce the risk of disconnection of the second line 132. There is a spacing I between the second line 132 and the adjacent first line 122. Under the limitation of the requirement of a specific impedance, the spacing I can be determined according to the width W1 and thickness of the second line 132 and the parameters of the dielectric layer 150, thereby improving the impedance matching effect.

[0071] In summary, since the coaxial through-hole structure disclosed herein has coplanar ground wires and signal lines (the first line and the second line), and the first conductive structure and the second conductive structure can be electrically insulated through the insulating layer, the coaxial through-hole structure disclosed herein can have better electromagnetic noise shielding and impedance matching effects to improve the high-frequency signal integrity. In addition, the coaxial through-hole structure disclosed herein can reduce the number of dielectric layers to reduce the thickness of the coaxial through-hole structure. Therefore, the coaxial through-hole structure disclosed herein can also have the technical effect of reducing costs.

[0072] Although the present invention has been disclosed as above in embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to that defined by the scope of the patent application.

Claims

1. A coaxial through-hole structure, characterized in that, it comprises: a substrate having a first surface; a first conductive structure comprising a first circuit on the first surface and a first through-hole penetrating the substrate; a second conductive structure comprising a second circuit on the first surface of the substrate and a second through-hole penetrating the substrate, the first through-hole and the second through-hole extending in a first direction, the first circuit and the second circuit extending in a second direction, and the second direction being perpendicular to the first direction; and an insulating layer located between the first through-hole and the second through-hole, wherein the first conductive structure and the second conductive structure are electrically insulated, and the first circuit and the second circuit are coplanar, the insulating layer has a protruding portion at the end of the insulating layer close to the first surface, the protruding portion of the insulating layer protrudes along the second direction away from the second through-hole, and the protruding portion of the insulating layer overlaps with the substrate in the first direction.

2. The coaxial through-hole structure according to claim 1, characterized in that, wherein the first through-hole of the first conductive structure surrounds the second through-hole of the second conductive structure and the insulating layer.

3. The coaxial through-hole structure according to claim 1, characterized in that, wherein the insulating layer, the first through-hole and the second through-hole are coaxial.

4. The coaxial through-hole structure according to claim 1, characterized in that, wherein the first through-hole of the first conductive structure, the protruding portion of the insulating layer, and the second circuit of the second conductive structure overlap in the first direction.

5. The coaxial through-hole structure according to claim 1, characterized in that, wherein the substrate further comprises a second surface opposite to the first surface, and the coaxial through-hole structure further comprises a dielectric layer between the first surface and the second surface, and the protruding portion of the insulating layer contacts the dielectric layer.

6. A manufacturing method of a coaxial through-hole structure, characterized in that, it comprises: forming a first through-hole in the substrate; forming a first conductive material on the first surface of the substrate and in the first through-hole, wherein the substrate further comprises a second surface opposite to the first surface; forming a groove recessed from the first surface, such that the dielectric layer between the first surface and the second surface is exposed from the first conductive material, and the groove communicates with the first through-hole; forming an insulating layer in the first through-hole and the groove, further comprising: forming an insulating layer material in the first through-hole and the groove such that the insulating layer material contacts the dielectric layer; and forming a second through-hole in the insulating layer material to form the insulating layer, wherein the insulating layer has a protruding portion in the groove, the protruding portion of the insulating layer protrudes along the second direction away from the second through-hole, and the protruding portion of the insulating layer overlaps with the substrate in the first direction; forming a second conductive material on the first surface of the substrate and in the first through-hole; and patterning the first conductive material and the second conductive material to form a first circuit and a second circuit on the first surface, such that the remaining first conductive material and the remaining second conductive material are electrically insulated by the insulating layer in the groove, and the first circuit and the second circuit are coplanar.

7. The manufacturing method of the coaxial through-hole structure according to claim 6, characterized in that, wherein the coaxial through-hole structure further comprises a second surface opposite to the first surface, and forming the groove further comprises: drilling a hole from the first surface along a first direction.

8. The manufacturing method of the coaxial through-hole structure according to claim 6, characterized in that, wherein forming the second conductive material on the first surface of the substrate and in the first through-hole further comprises: forming the second conductive material in the second through-hole, and causing the first conductive material in the first through-hole to surround the insulating layer and the second conductive material in the second through-hole.

9. The manufacturing method of the coaxial through-hole structure according to claim 8, characterized in that, wherein forming the second conductive material on the first surface of the substrate and in the first through-hole further comprises: causing the insulating layer, the first conductive material in the first through-hole, and the second conductive material in the second through-hole to be coaxial.

10. The manufacturing method of the coaxial through-hole structure according to claim 7, characterized in that, wherein patterning the first conductive material and the second conductive material to form the first circuit and the second circuit further comprises: causing the first conductive material in the first through-hole, the protruding portion of the insulating layer, and the second circuit to overlap in the first direction.

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