Wiring module and method for manufacturing wiring module

Abstract

To provide a wiring module with which it is possible to reduce the skew of a differential signal.SOLUTION: The wiring module comprises a substrate, and first and second wiring units for respectively transmitting first and second signals constituting a differential signal. Each of the first and the second wiring units includes a first wiring laid on the substrate, a second wiring laid on the substrate, and a skew adjustment element mounted on the substrate. The skew adjustment element includes a third wiring. The third wiring has a first end conductively joined to the first wiring, and a second end conductively joined to the second wiring. The skew adjustment element further includes a dielectric body in one or both of the first and the second wiring units, and the third wiring is laid on the surface of the dielectric body not including a region facing the substrate. A first length of the third wiring of the skew adjustment element from the first end to the second end of the first wiring unit is different from a second length of the third wiring of the skew adjustment element from the first end to the second end of the second wiring unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a wiring module and a method for manufacturing the wiring module. [Background technology]

[0002] Patent Document 1 discloses a technique related to a cable harness and a manufacturing method of the cable harness. The cable harness includes a plurality of electric wires. Both ends of the plurality of electric wires are electrically connected to a connecting member. Every two electric wires form a wire pair, and the signal propagation delay time difference in each wire pair is 10 ps / m or less. The plurality of electric wires are connected to the connecting member with the ends of the plurality of electric wires aligned in the longitudinal direction. The connecting member is provided with a circuit section connected to the plurality of electric wires. The circuit section has terminals for connection to an external device. At least one of the plurality of electric wires has a flexible section. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-185325 Summary of the Invention [Problem to be solved by the invention]

[0004] In high-speed communications, differential signals are transmitted using, for example, two signal lines. Skew occurs in the differential signals due to the difference in length between the two signal lines transmitting the differential signals and the density of the resin that coats the two signal lines. If the skew in the differential signals becomes large, the accuracy of the differential signal reception at the receiving end is impaired.

[0005] An object of the present disclosure is to provide a wiring module capable of reducing skew in differential signals and a method for manufacturing the wiring module. [Means for solving the problem]

[0006] A wiring module according to an embodiment of the present disclosure includes a substrate and first and second wiring sections that transmit first and second signals, respectively, that constitute a differential signal. Each of the first and second wiring sections includes a first wiring provided on the substrate, a second wiring provided on the substrate, and a skew adjustment element mounted on the substrate. The skew adjustment element includes a third wiring. The third wiring has a first end conductively connected to the first wiring and a second end conductively connected to the second wiring. In one or both of the first and second wiring sections, the skew adjustment element further includes a dielectric, and the third wiring is provided on a surface of the dielectric except for a region facing the substrate. A first length from the first end to the second end of the third wiring of the skew adjustment element of the first wiring section is different from a second length from the first end to the second end of the third wiring of the skew adjustment element of the second wiring section. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to provide a wiring module capable of reducing skew in differential signals and a method for manufacturing the wiring module. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a wiring module. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II shown in FIG. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III shown in FIG. [Figure 4] FIG. 4 is a flowchart showing a method for manufacturing a wiring module. [Figure 5] FIG. 5 is a perspective view showing an example of a plurality of skew adjustment elements each having a third wiring having a different length. [Figure 6] FIG. 6 is a side view showing an example of a plurality of skew adjustment elements each having a different dielectric constant. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Description of the embodiments of the present disclosure] First, the details of the embodiments of the present disclosure will be listed and described. [1] A wiring module according to one embodiment of the present disclosure includes a substrate and first and second wiring sections that transmit first and second signals, respectively, constituting a differential signal. Each of the first and second wiring sections includes a first wiring provided on the substrate, a second wiring provided on the substrate, and a skew adjustment element mounted on the substrate. The skew adjustment element includes a third wiring. The third wiring has a first end conductively connected to the first wiring and a second end conductively connected to the second wiring. In one or both of the first and second wiring sections, the skew adjustment element further includes a dielectric, and the third wiring is provided on the surface of the dielectric except for a region facing the substrate. A first length from the first end to the second end of the third wiring of the skew adjustment element of the first wiring section is different from a second length from the first end to the second end of the third wiring of the skew adjustment element of the second wiring section.

[0010] In the wiring module of [1] above, the length (first length) of the third wiring of the skew adjustment element of the first wiring section is different from the length (second length) of the third wiring of the skew adjustment element of the second wiring section. In this case, by selecting a combination of the first length and the second length, it is possible to make the skew between the first signal after being transmitted through the first wiring section and the second signal after being transmitted through the second wiring section smaller than the skew between the first signal before being transmitted through the first wiring section and the second signal before being transmitted through the second wiring section. Therefore, the wiring module of [1] above can reduce the skew of differential signals.

[0011] [2] In the wiring module of [1] above, the skew adjustment elements of both the first wiring section and the second wiring section may include a dielectric. The thickness of the dielectric of the skew adjustment element of the first wiring section may be different from the thickness of the dielectric of the skew adjustment element of the second wiring section, so that the first length may be different from the second length. Such a configuration of the skew adjustment element makes it possible to realize an embodiment in which the first length is different from the second length with a simple structure.

[0012] [3] A wiring module according to an embodiment of the present disclosure includes a substrate and first and second wiring sections that transmit first and second signals, respectively, constituting a differential signal. Each of the first and second wiring sections includes a first wiring section provided on the substrate, a second wiring section provided on the substrate, and a skew adjustment element mounted on the substrate. The skew adjustment element includes a third wiring section. The third wiring section has a first end conductively joined to the first wiring section and a second end conductively joined to the second wiring section. In both the first and second wiring sections, the skew adjustment element further includes a dielectric, and the third wiring section is provided on a surface of the dielectric section excluding a region facing the substrate. The first dielectric constant of the dielectric section of the skew adjustment element in the first wiring section is different from the second dielectric constant of the dielectric section of the skew adjustment element in the second wiring section.

[0013] In the wiring module of [3] above, the dielectric constant (first dielectric constant) of the dielectric of the skew adjustment element of the first wiring section is different from the dielectric constant (second dielectric constant) of the dielectric of the skew adjustment element of the second wiring section. The propagation speed of a signal transmitted through the third wiring changes depending on the dielectric constant of the dielectric adjacent to the third wiring. Therefore, by selecting a combination of the first dielectric constant and the second dielectric constant, it is possible to make the skew between the first signal after being transmitted through the first wiring section and the second signal after being transmitted through the second wiring section smaller than the skew between the first signal before being transmitted through the first wiring section and the second signal before being transmitted through the second wiring section. Therefore, the wiring module of [3] above can reduce the skew of differential signals.

[0014] [4] In the wiring modules of [1] to [3] above, the dielectrics of the skew adjustment elements of the first and second wiring sections may contain one or both of ceramic and glass epoxy. In this case, by making the composition of the ceramic or glass epoxy different between the skew adjustment elements of the first wiring section and the skew adjustment elements of the second wiring section, the dielectric constants of the dielectrics of these skew adjustment elements can be effectively made different.

[0015] [5] In the wiring module according to any one of [1] to [4] above, the third wiring of the skew adjustment element of the first wiring section and the second wiring section may contain at least one metal selected from the group consisting of gold, silver, copper, tin, nickel, and chromium. In this case, the third wiring can be formed by plating, for example, to be strongly adhered to the surface of the dielectric.

[0016] [6] A method for manufacturing a wiring module according to an embodiment of the present disclosure includes the steps of preparing a first wiring section and a second wiring section, measuring skew, and conductively bonding the first and second wiring sections. The first and second wiring sections have first and second wiring sections provided on a substrate, and transmit first and second signals constituting a differential signal, respectively. In the skew measuring step, the skew between the first and second signals is measured. In the conductive bonding step, a skew adjustment element including a third wiring section having a first end and a second end is disposed on the substrate in each of the first and second wiring sections, and the first end is conductively bonded to the first wiring section and the second end is conductively bonded to the second wiring section. In one or both of the first and second wiring sections, the skew adjustment element further includes a dielectric. The third wiring section is provided on the surface of the dielectric section except for a region facing the substrate. In the conductive joining step, a combination of a first length from the first end to the second end of the third wiring of the skew adjustment element of the first wiring part and a second length from the first end to the second end of the third wiring of the skew adjustment element of the second wiring part is selected so that the skew between the first signal transmitted through the first wiring part in which the skew adjustment element is provided and the second signal transmitted through the second wiring part in which the skew adjustment element is provided is smaller than the skew measured in the measuring step.

[0017] In the manufacturing method [6] above, in the conductive bonding step, a combination of a length (first length) from the first end to the second end of the third wiring of the skew adjustment element in the first wiring section and a length (second length) from the first end to the second end of the third wiring of the skew adjustment element in the second wiring section is selected. At this time, the combination of the first length and the second length is selected so that the skew between the first signal transmitted through the first wiring section provided with the skew adjustment element and the second signal transmitted through the second wiring section provided with the skew adjustment element is smaller than the skew measured in the measuring step. Therefore, the manufacturing method of the wiring module [6] above can reduce the skew of differential signals.

[0018] [7] A method for manufacturing a wiring module according to an embodiment of the present disclosure includes the steps of preparing a first wiring section and a second wiring section, measuring skew, and conductively bonding the first and second wiring sections. The first and second wiring sections have first and second wiring sections provided on a substrate, and transmit first and second signals constituting a differential signal, respectively. In the skew measuring step, the skew between the first and second signals is measured. In the conductive bonding step, a skew adjustment element including a third wiring section having a first end and a second end is disposed on the substrate in each of the first and second wiring sections, and the first end is conductively bonded to the first wiring section and the second end is conductively bonded to the second wiring section. In one or both of the first and second wiring sections, the skew adjustment element further includes a dielectric. The third wiring section is provided on the surface of the dielectric section except for a region facing the substrate. In the conductive joining step, a combination of a first dielectric constant of the dielectric of the skew adjustment element of the first wiring section and a second dielectric constant of the dielectric of the skew adjustment element of the second wiring section is selected so that the skew between the first signal after being transmitted through the first wiring section provided with the skew adjustment element and the second signal after being transmitted through the second wiring section provided with the skew adjustment element is smaller than the skew measured in the measuring step.

[0019] In the manufacturing method [7] above, in the conductive bonding step, a combination of the dielectric constant (first dielectric constant) of the skew adjustment element of the first wiring section and the dielectric constant (second dielectric constant) of the skew adjustment element of the second wiring section is selected. The combination of the first dielectric constant and the second dielectric constant is selected so that the skew between the first signal transmitted through the first wiring section provided with the skew adjustment element and the second signal transmitted through the second wiring section provided with the skew adjustment element is smaller than the skew measured in the measuring step. This is because the propagation speed of a signal transmitted through the third wiring changes depending on the dielectric constant of the dielectric adjacent to the third wiring. Therefore, the manufacturing method of the wiring module [7] above can reduce the skew of differential signals.

[0020] [Details of the embodiments of the present disclosure] Specific examples of the wiring module and the manufacturing method of the wiring module according to the present disclosure will be described below with reference to the drawings. Note that the present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims. In the following description, the same elements in the drawings will be given the same reference numerals, and duplicate explanations will be omitted.

[0021] FIG. 1 is a perspective view showing a wiring module 1 according to an embodiment of the present disclosure. In this embodiment, the wiring module 1 is, for example, a paddle card built into a connector. The wiring module 1 includes a substrate 2, a first wiring section 10, and a second wiring section 20. The substrate 2 is an insulating flat plate having a flat main surface 3. The first wiring section 10 and the second wiring section 20 are provided on the main surface 3 of the substrate 2. The first wiring section 10 and the second wiring section 20 extend along direction D1. The first wiring section 10 and the second wiring section 20 are arranged parallel to each other and aligned in a direction intersecting direction D1. The first wiring section 10 and the second wiring section 20 transmit a first signal and a second signal, respectively, that constitute a differential signal.

[0022] The first wiring section 10 has a first wiring 11, a second wiring 12, and a skew adjustment element 30. The first wiring 11 and the second wiring 12 are arranged side by side on the same straight line along the direction D1 on the main surface 3 of the substrate 2. The first wiring 11 and the second wiring 12 are in the form of a film.

[0023] The first wiring 11 includes a pad 13 and a pad 14. The second wiring 12 includes a pad 15. The pad 13 is located at a first end of the first wiring 11, and the pad 14 is located at a second end of the first wiring 11. The pad 15 is located at a first end of the second wiring 12. The pad 14 is aligned with the pad 15 in the direction D1. A cable 4 is connected to the pad 13. The cable 4 has a resin coating 51 and a signal line 52. The signal line 52 has a linear shape with a circular cross section and is conductively bonded to the pad 13 with a conductive adhesive. The resin coating 51 covers the outer periphery of the signal line 52 so as to cover the signal line 52. A second end of the second wiring 12 is connected to an output unit of the wiring module 1 and is connected to an external element such as a receiver.

[0024] The skew adjustment element 30 is interposed between the pads 14 and 15 in the first wiring section 10, and electrically connects the pads 14 and 15. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, showing the cross section of the skew adjustment element 30 taken along direction D1. As shown in FIGS. 1 and 2, the skew adjustment element 30 has a third wiring 31 and a dielectric 32.

[0025] The dielectric 32 has a rectangular parallelepiped shape that is long in the direction D1. The dielectric 32 has flat first and second end faces 32a and 32b, with the direction D1 as the normal direction. The first and second end faces 32a and 32b face in opposite directions in the direction D1. The first end face 32a of the dielectric 32 is located on the pad 14, and the second end face 32b of the dielectric 32 is located on the pad 15. The dielectric 32 further has flat upper and lower faces 32c and 32d that face in a direction intersecting the main surface 3. The upper and lower faces 32c and 32d face in opposite directions. The lower face 32d faces the main surface 3. The upper face 32c faces, for example, in the same direction as the main surface 3.

[0026] The third wiring 31 is provided on the surface of the dielectric 32 excluding the region facing the substrate 2 (i.e., the bottom surface 32d) and is fixed to this surface. In the illustrated example, the third wiring 31 is provided on the first end surface 32a, the second end surface 32b, and the top surface 32c of the dielectric 32, but is not provided on the side surfaces of the dielectric 32. The third wiring 31 has a first end 31a and a second end 31b. The first end 31a and the second end 31b are formed so as to be flush with the bottom surface 32d of the dielectric 32. As shown in FIG. 1 , the first end 31a of the third wiring 31 is conductively joined to the pad 14, and the second end 31b of the third wiring 31 is conductively joined to the pad 15. The third wiring 31 is formed on the surface of the dielectric 32 by plating, for example.

[0027] The second wiring section 20 has a first wiring 21, a second wiring 22, and a skew adjustment element 40. The first wiring 21 and the second wiring 22 are arranged side by side on the same straight line along the direction D1 on the main surface 3 of the substrate 2. The first wiring 21 and the second wiring 22 are in the form of a film.

[0028] The first wiring 21 includes a pad 23 and a pad 24. The second wiring 22 includes a pad 25. The pad 23 is located at a first end of the first wiring 21, and the pad 24 is located at a second end of the first wiring 21. The pad 25 is located at a first end of the second wiring 22. The pad 24 is aligned with the pad 25 in the direction D1. A cable 5 is connected to the pad 23. The cable 5 has a resin coating 53 and a signal line 54. The signal line 54 has a linear shape with a circular cross section and is conductively bonded to the pad 23 with a conductive adhesive. The resin coating 53 covers the outer periphery of the signal line 54 so as to cover the signal line 54. A second end of the second wiring 22 is connected to an output unit of the wiring module 1 and is connected to an external element such as a receiver.

[0029] The skew adjustment element 40 is interposed between the pad 24 and the pad 25 in the second wiring section 20, and electrically connects the pad 24 to the pad 25. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 1, showing a cross section of the skew adjustment element 40 taken along direction D1. As shown in Figs. 1 and 2, the skew adjustment element 40 has a third wiring 41 and a dielectric 42.

[0030] In this embodiment, the dielectric 42 has a dielectric constant equal to that of the dielectric 32 of the skew adjustment element 30. The dielectric 42 has a rectangular parallelepiped shape elongated in the direction D1. The dielectric 42 has flat first and second end faces 42a and 42b, with the direction D1 as its normal direction. The first and second end faces 42a and 42b face in opposite directions in the direction D1. The first end face 42a of the dielectric 42 is located on the pad 24, and the second end face 42b of the dielectric 42 is located on the pad 25. The dielectric 42 further has flat upper and lower faces 42c and 42d that face in a direction intersecting the principal surface 3. The upper and lower faces 42c and 42d face in opposite directions. The lower face 42d faces the principal surface 3. The upper face 42c faces, for example, in the same direction as the principal surface 3.

[0031] The third wiring 41 is provided on the surface of the dielectric 42 excluding the region facing the substrate 2 (i.e., the bottom surface 42d) and is fixed to this surface. In the illustrated example, the third wiring 41 is provided over the first end surface 42a, the second end surface 42b, and the top surface 42c of the dielectric 42, but is not provided on the side surfaces of the dielectric 42. The third wiring 41 has a first end 41a and a second end 41b. The first end 41a and the second end 41b are formed so as to be flush with the bottom surface 42d of the dielectric 42. As shown in FIG. 1 , the first end 41a of the third wiring 41 is conductively joined to the pad 24, and the second end 41b of the third wiring 41 is conductively joined to the pad 25. The third wiring 41 is formed on the surface of the dielectric 42 by plating, for example.

[0032] The pads 13 to 15 and pads 23 to 25 are made of a metal such as copper (Cu). The first wiring 11 (excluding pads 13 and 14), the second wiring 12 (excluding pad 15), the first wiring 21 (excluding pads 23 and 24), and the second wiring 22 (excluding pad 25) are made of a metal such as copper. The dielectrics 32 and 42 are made of a material such as ceramic or glass epoxy, or may contain both ceramic and glass epoxy. The third wiring 31 and third wiring 41 are made of a metal including at least one of gold (Au), silver (Ag), copper, tin (Sn), nickel (Ni), and chromium (Cr).

[0033] The thickness of the dielectric 32 in a direction intersecting the principal surface 3 is greater than the thickness of the dielectric 42 in the same direction. In other words, the lengths of the first end face 32a and the second end face 32b in the direction intersecting the principal surface 3 are greater than the lengths of the first end face 42a and the second end face 42b in the same direction. Therefore, the length from the first end 31a to the second end 31b of the third wiring 31 of the skew adjustment element 30 (first length) is greater than the length from the first end 41a to the second end 41b of the third wiring 41 of the skew adjustment element 40 (second length). In this manner, in this embodiment, the length of the third wiring 31 and the length of the third wiring 41 are different from each other. The thicknesses of the dielectrics 32 and 42 are, for example, not less than 0.1 mm and not more than 3 mm. The length from the first end 31a to the second end 31b of the third wiring 31 and the length from the first end 41a to the second end 41b of the third wiring 41 are, for example, not less than 0.3 mm and not more than 5 mm.

[0034] 4 is a flowchart showing a method for manufacturing the wiring module 1. This manufacturing method includes step ST1 of preparing the first wiring section 10 and the second wiring section 20, step ST2 of measuring skew, and step ST3 of conductive bonding.

[0035] In step ST1, first, a substrate 2 is prepared, on whose main surface 3 the first wiring 11 and the second wiring 12 of the first wiring portion 10 and the first wiring 21 and the second wiring 22 of the second wiring portion 20 are formed. Then, the signal line 52 of the cable 4 is conductively joined to the pad 13 of the first wiring 11, and the signal line 54 of the cable 5 is conductively joined to the pad 23 of the first wiring 21.

[0036] In step ST2, the skew is measured between the first signal transmitted from the signal line 52 of the cable 4 to the first wiring 11 and the second signal transmitted from the signal line 54 of the cable 5 to the first wiring 21. Note that the skew between the first signal transmitted through the signal line 52 and the second signal transmitted through the signal line 54 may be measured before the signal lines 52 and 54 are conductively joined to the pads 13 and 23.

[0037] In step ST3, first, multiple skew adjustment elements with different lengths of third wiring are prepared. Parts (a), (b), and (c) of FIG. 5 are perspective views showing examples of multiple skew adjustment elements 60. These skew adjustment elements 60 have third wiring 61 and a dielectric 62. The third wiring 61 corresponds to the third wiring 31 and 41 of the skew adjustment elements 30 and 40. The dielectric 62 corresponds to the dielectric 32 and 42 of the skew adjustment elements 30 and 40. These skew adjustment elements 60 differ from one another in the thickness of the dielectric 62, and as a result, the lengths of the third wiring 61 also differ from one another. The skew adjustment element 60 shown in part (a) of FIG. 5 has the smallest thickness of the dielectric 62, and as a result, the skew adjustment element 60 shown in part (a) of FIG. 5 has the shortest third wiring 61. Furthermore, the thickness of the dielectric 62 of the skew adjustment element 60 shown in part (c) of FIG. 5 is the largest, and as a result, the length of the third wiring 61 of the skew adjustment element 60 shown in part (c) of FIG. 5 is the longest.

[0038] In this step ST3, based on the value of the skew measured in step ST2, a combination of the length (first length) from the first end 31a to the second end 31b of the third wiring 31 of the skew adjustment element 30 and the length (second length) from the first end 41a to the second end 41b of the third wiring 41 of the skew adjustment element 40 is selected from among the multiple skew adjustment elements 60. That is, the lengths of the third wiring 31 and the third wiring 41 are selected so that the skew between the first signal transmitted through the first wiring section 10 in which the skew adjustment element 30 is provided and the second signal transmitted through the second wiring section 20 in which the skew adjustment element 40 is provided is smaller than the skew measured in step ST2. For example, the skew adjustment elements 60 to be used for the skew adjustment elements 30 and 40 are selected from the plurality of skew adjustment elements 60 so that the difference between the signal propagation length of the third wiring 31 and the signal propagation length of the third wiring 41 is closest to the signal propagation length corresponding to the skew measured in step ST2. Note that in the illustrated example, the third wiring 31 is longer than the third wiring 41, but the third wiring 41 may be longer than the third wiring 31 depending on the value of the skew measured in step ST2.

[0039] In step ST3, the skew adjustment elements 30 and 40 are then placed at predetermined positions on the main surface 3 of the substrate 2. Then, the first end 31a of the third wiring 31 of the skew adjustment element 30 is conductively joined to the first wiring 11, and the second end 31b of the third wiring 31 of the skew adjustment element 30 is conductively joined to the second wiring 12. Similarly, the first end 41a of the third wiring 41 of the skew adjustment element 40 is conductively joined to the first wiring 21, and the second end 41b of the third wiring 41 of the skew adjustment element 40 is conductively joined to the second wiring 22.

[0040] The effects obtained by the above-described wiring module 1 and manufacturing method thereof according to this embodiment will now be described. In the wiring module 1 according to this embodiment, the length (first length) of the third wiring 31 of the skew adjustment element 30 in the first wiring section 10 is different from the length (second length) of the third wiring 41 of the skew adjustment element 40 in the second wiring section 20. In this case, by selecting a combination of the first length and the second length, it is possible to make the skew between the first signal after being transmitted through the first wiring section 10 and the second signal after being transmitted through the second wiring section 20 smaller than the skew between the first signal before being transmitted through the first wiring section 10 and the second signal before being transmitted through the second wiring section 20. Therefore, the wiring module 1 according to this embodiment can reduce the skew of differential signals.

[0041] As in the present embodiment, the skew adjustment elements 30, 40 of both the first wiring section 10 and the second wiring section 20 may include a dielectric (dielectrics 32, 42). The thickness of the dielectric 32 of the skew adjustment element 30 of the first wiring section 10 may be different from the thickness of the dielectric 42 of the skew adjustment element 40 of the second wiring section 20, so that the first length may be different from the second length. With such a configuration of the skew adjustment elements 30, 40, it is possible to realize an embodiment in which the first length is different from the second length with a simple structure.

[0042] As in the present embodiment, the third wirings 31, 41 of the skew adjustment elements 30, 40 of the first wiring section 10 and the second wiring section 20 may contain at least one metal of tin, nickel, and chromium. In this case, the third wirings 31, 41 that are strongly adhered to the surfaces of the dielectrics 32, 42 can be formed by, for example, plating.

[0043] In the manufacturing method of the wiring module 1 of this embodiment, a combination of the first length and the second length is selected in step ST3. At this time, the combination of the first length and the second length is selected so that the skew between the first signal transmitted through the first wiring section 10 provided with the skew adjustment element 30 and the second signal transmitted through the second wiring section 20 provided with the skew adjustment element 40 is smaller than the skew measured in step ST2. Therefore, according to the manufacturing method of this embodiment, the skew of the differential signal can be reduced.

[0044] [Variations] In the above embodiment, the dielectric constant of the dielectric 32 of the skew adjustment element 30 and the dielectric 42 of the skew adjustment element 40 are equal to each other. However, the dielectric constant (first dielectric constant) of the dielectric 32 and the dielectric 42 (second dielectric constant) may be different from each other. The propagation speed of the first signal transmitted through the third wiring 31 varies depending on the dielectric constant of the dielectric 32 adjacent to the third wiring 31. Similarly, the propagation speed of the second signal transmitted through the third wiring 41 varies depending on the dielectric constant of the dielectric 42 adjacent to the third wiring 41. Therefore, the dielectric constants of the dielectrics 32 and 42 are different from each other, thereby reducing the skew between the first and second signals. The dielectric constants of the dielectrics 32 and 42 are, for example, 1.5 or more and 10 or less. In this modification, the thickness of the dielectric 32 and the thickness of the dielectric 42 may be equal to each other, and the first length of the third wiring 31 and the second length of the third wiring 41 may be equal to each other.

[0045] In this modification, instead of multiple skew adjustment elements with different lengths of third wiring, multiple skew adjustment elements with different dielectric permittivities are prepared in step ST3 of the above embodiment. Parts (a), (b), and (c) of FIG. 6 are side views showing examples of multiple such skew adjustment elements 70. Each of these skew adjustment elements 70 has a third wiring 71 and a dielectric 72. The third wiring 71 corresponds to the third wirings 31 and 41 of the skew adjustment elements 30 and 40. The dielectric 72 corresponds to the dielectrics 32 and 42 of the skew adjustment elements 30 and 40. The dielectrics 72 of the skew adjustment elements 70 differ from one another in the permittivity of the dielectric 72. In the figure, the permittivity of the dielectric 72 is indicated by different shades of color. The skew adjustment element 60 shown in Part (a) of FIG. 6 has the smallest permittivity of the dielectric 62, while the skew adjustment element 60 shown in Part (c) of FIG. 6 has the largest permittivity of the dielectric 62.

[0046] In the wiring module of this modified example, by selecting a combination of the dielectric constant of the dielectric 32 and the dielectric constant of the dielectric 42, it is possible to make the skew between the first signal after being transmitted through the first wiring section 10 and the second signal after being transmitted through the second wiring section 20 smaller than the skew between the first signal before being transmitted through the first wiring section 10 and the second signal before being transmitted through the second wiring section 20. Therefore, the wiring module of this modified example can reduce the skew of the differential signals.

[0047] Furthermore, in the manufacturing method of the wiring module of this modified example, a combination of the dielectric constants of the dielectrics 32 and 42 is selected in step ST3. At this time, the combination of the dielectric constants of the dielectrics 32 and 42 is selected so that the skew between the first signal transmitted through the first wiring section 10 provided with the skew adjustment element 30 and the second signal transmitted through the second wiring section 20 provided with the skew adjustment element 40 is smaller than the skew measured in step ST2. Therefore, according to the manufacturing method of this modified example, the skew of the differential signal can be reduced.

[0048] Although the present invention has been specifically described above based on the embodiments and modifications, the present invention is not limited to the above embodiments and modifications and can be modified within the scope of the present invention. For example, the shapes of the dielectrics 32 and 42 are not limited to rectangular parallelepipeds as in the above embodiments, but may be cubic or frustum, or may have a shape including a curved surface, such as a semi-cylindrical shape. Furthermore, in the above embodiments, both the skew adjustment element 30 and the skew adjustment element 40 have a dielectric, but only one of the skew adjustment element 30 and the skew adjustment element 40 may have a dielectric.

[0049] In addition, in the above embodiment, the third wirings 31, 41 are not provided on the side surfaces of the dielectrics 32, 42, but the third wirings 31, 41 may be further provided on the side surfaces of the dielectrics 32, 42. In that case, the third wirings 31, 41 may be provided only in regions of the side surfaces of the dielectrics 32, 42 that are far from the substrate 2. [Explanation of symbols]

[0050] 1...Wiring module 2...Substrate 3...Main surface 4,5…cable 10...1st wiring section 11,21…1st wiring 12,22…Second wiring 13,14,15,23,24,25...Pads 20…Second wiring section 30, 40, 60, 70...Skew adjustment element 31,41,61,71…Third wiring 31a, 41a...1st end 31b,41b…2nd end 32, 42, 62, 72...Dielectric 32a, 42a...first end surface 32b, 42b…Second end surface 32c,42c…Top surface 32d,42d…bottom surface 51, 53...Resin coating 52, 54...Signal lines D1…direction

Claims

1. A substrate; a first wiring section and a second wiring section that transmit a first signal and a second signal that constitute a differential signal, respectively; Equipped with each of the first wiring section and the second wiring section has a first wiring provided on the substrate, a second wiring provided on the substrate, and a skew adjustment element mounted on the substrate, the skew adjustment element including a third wiring; the third wiring has a first end conductively joined to the first wiring and a second end conductively joined to the second wiring; In one or both of the first wiring portion and the second wiring portion, the skew adjustment element further includes a dielectric, and the third wiring is provided on a surface of the dielectric except for a region facing the substrate; A wiring module, wherein a first length from the first end to the second end of the third wiring of the skew adjustment element of the first wiring section is different from a second length from the first end to the second end of the third wiring of the skew adjustment element of the second wiring section.

2. the skew adjustment elements of both the first wiring portion and the second wiring portion include the dielectric; 2. The wiring module according to claim 1, wherein the thickness of the dielectric of the skew adjustment element of the first wiring section is different from the thickness of the dielectric of the skew adjustment element of the second wiring section, and thus the first length is different from the second length.

3. A substrate; a first wiring section and a second wiring section that transmit a first signal and a second signal that constitute a differential signal, respectively; Equipped with each of the first wiring section and the second wiring section has a first wiring provided on the substrate, a second wiring provided on the substrate, and a skew adjustment element mounted on the substrate, the skew adjustment element including a third wiring; the third wiring has a first end conductively joined to the first wiring and a second end conductively joined to the second wiring; In both the first wiring portion and the second wiring portion, the skew adjustment element further includes a dielectric, and the third wiring is provided on a surface of the dielectric except for a region facing the substrate; a first dielectric constant of the dielectric of the skew adjustment element of the first wiring section is different from a second dielectric constant of the dielectric of the skew adjustment element of the second wiring section;

4. 4. The wiring module according to claim 3, wherein the dielectric of the skew adjustment elements of the first wiring section and the second wiring section includes one or both of ceramic and glass epoxy.

5. 5. The wiring module according to claim 1, wherein the third wiring of the skew adjustment element of the first wiring section and the second wiring section includes at least one metal selected from the group consisting of gold, silver, copper, tin, nickel, and chromium.

6. a step of preparing a first wiring section and a second wiring section having first wiring and second wiring provided on a substrate, the first wiring section and the second wiring section transmitting a first signal and a second signal constituting a differential signal, respectively; measuring the skew between the first signal and the second signal; a step of disposing a skew adjustment element on the substrate, the skew adjustment element including a third wiring having a first end and a second end, in each of the first wiring portion and the second wiring portion, and conductively joining the first end to the first wiring and the second end to the second wiring; Including, In one or both of the first wiring portion and the second wiring portion, the skew adjustment element further includes a dielectric, and the third wiring is provided on a surface of the dielectric except for a region facing the substrate; A method for manufacturing a wiring module, wherein in the conductive joining process, a combination of a first length from the first end to the second end of the third wiring of the skew adjustment element of the first wiring section and a second length from the first end to the second end of the third wiring of the skew adjustment element of the second wiring section is selected so that the skew between the first signal transmitted through the first wiring section in which the skew adjustment element is provided and the second signal transmitted through the second wiring section in which the skew adjustment element is provided is smaller than the skew measured in the measuring process.

7. a step of preparing a first wiring section and a second wiring section having first wiring and second wiring provided on a substrate, the first wiring section and the second wiring section transmitting a first signal and a second signal constituting a differential signal, respectively; measuring the skew between the first signal and the second signal; a step of disposing a skew adjustment element on the substrate, the skew adjustment element including a third wiring having a first end and a second end, in each of the first wiring portion and the second wiring portion, and conductively joining the first end to the first wiring and the second end to the second wiring; Including, In one or both of the first wiring portion and the second wiring portion, the skew adjustment element further includes a dielectric, and the third wiring is provided on a surface of the dielectric except for a region facing the substrate; A method for manufacturing a wiring module, wherein in the conductive joining step, a combination of a first dielectric constant of the dielectric of the skew adjustment element of the first wiring part and a second dielectric constant of the dielectric of the skew adjustment element of the second wiring part is selected so that the skew between the first signal transmitted through the first wiring part in which the skew adjustment element is provided and the second signal transmitted through the second wiring part in which the skew adjustment element is provided is smaller than the skew measured in the measuring step.

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