Wiring substrate and electronic device

Abstract

The wiring substrate disclosed in the present invention comprises: an insulating substrate having a first surface; a first differential signal line located on the first surface; and a second differential signal line located on the first surface and arranged in a first direction with the first differential signal line. The first differential signal line comprises: a pair of first signal conductors extending in a second direction intersecting the first direction; and a pair of first grounding conductors sandwiching the pair of first signal conductors and arranged along the first signal conductors. The second differential signal line comprises: a pair of second signal conductors extending in a second direction; and a pair of second grounding conductors sandwiching the pair of second signal conductors and arranged along the second signal conductors. Furthermore, the wiring substrate comprises a first film arranged across adjacent first grounding conductors and second grounding conductors in the second direction when viewed from above toward the first surface.

Description

Technical Field

[0001] The present disclosure relates to a wiring substrate and an electronic device. Background Art

[0002] As communication terminals become more popular and perform better, electronic devices are promoting the high frequency of electrical signals in order to transmit information at high speed and with large amounts of information. International Publication No. 2014 / 192687 discloses providing input and output terminals of a plurality of adjacent differential signal lines in order to improve frequency characteristics in a high frequency band. Summary of the invention

[0003] The wiring substrate disclosed in the present invention comprises: an insulating substrate having a first surface; a first differential signal line located on the first surface; and a second differential signal line located on the first surface and arranged in a first direction with the first differential signal line. The first differential signal line comprises: a pair of first signal conductors extending in a second direction intersecting the first direction; and a pair of first grounding conductors sandwiching the pair of first signal conductors and arranged along the first signal conductors. The second differential signal line comprises: a pair of second signal conductors extending in a second direction; and a pair of second grounding conductors sandwiching the pair of second signal conductors and arranged along the second signal conductors. Furthermore, the wiring substrate comprises a first film arranged across adjacent first grounding conductors and second grounding conductors in the second direction when viewed from above toward the first surface.

[0004] The electronic device disclosed in the present invention comprises: the wiring substrate described above; and an electronic component connected to the wiring substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 This is a perspective view of a wiring substrate according to an embodiment of the present disclosure, as viewed from above.

[0006] Figure 2 This is a perspective view of a wiring substrate according to an embodiment of the present disclosure, as viewed from below.

[0007] Figure 3 This is a plan view of a wiring substrate according to an embodiment of the present disclosure, as viewed from above.

[0008] Figure 4 yes Figure 3 An enlarged view of the main part of the wiring substrate at IV.

[0009] Figure 5 yes Figure 3 An enlarged view of the main part at V of the wiring substrate.

[0010] Figure 6 This is a plan view of a wiring substrate according to an embodiment of the present disclosure, as viewed from above.

[0011] Figure 7 yes Figure 6 An enlarged view of the main part at VII of the wiring substrate.

[0012] Figure 8 yes Figure 6 This is an enlarged view of the main part of the wiring substrate at position VIII.

[0013] Fig. 9 yes Figure 6 An enlarged view of the main part at position IX of the wiring substrate.

[0014] Fig.10 yes Figure 1 An exploded perspective view of a wiring substrate.

[0015] Fig.11 This is a perspective view of an electronic device according to an embodiment of the present disclosure as viewed from below.

[0016] Fig.12 exist Fig.10 A three-dimensional view of an electronic device having a cover body based on a structure as viewed from below. DETAILED DESCRIPTION

[0017] The wiring substrate 1 and the electronic device 100 according to several exemplary embodiments of the present disclosure are described with reference to the accompanying drawings. In the following description, the structure in which the electronic component 101 is mounted on the wiring substrate 1 is referred to as the electronic device 100. In this specification, the wiring substrate 1 and the electronic device 100 are described by defining an orthogonal coordinate system xyz for convenience. In addition, there are cases in which the positive side in the z direction is set as the upper side and the negative side in the z direction is set as the lower side.

[0018] <Structure of Wiring Base 1>

[0019] Figure 1 The wiring substrate 1 shown includes an insulating substrate 10 , a first differential signal line 20 , a second differential signal line 30 , and a first film 41 .

[0020] The insulating base 10 may include a dielectric material. As the dielectric material, for example, a ceramic material such as an alumina sintered body, a mullite sintered body, a silicon carbide sintered body, an aluminum nitride sintered body, or a silicon nitride sintered body, or a glass ceramic material may be used.

[0021] The insulating substrate 10 can be formed by stacking dielectric materials. In addition, in this specification, there is a case where a structure formed by stacking dielectric materials is expressed as an insulating layer. The insulating substrate 10 has a first surface 11. The shape of the insulating substrate 10 can be, for example, rectangular or U-shaped when viewed from above toward the first surface 11. The size of the insulating substrate 10 can be in the range of 2mm×2mm to 25mm×50mm, and the height is 1mm to 10mm. The size of the insulating substrate 10 and the first surface 11 can be appropriately set. In addition, in this specification, there is a case where the first surface 11 is set as the upper surface and the surface opposite to the first surface 11 is set as the lower surface for description.

[0022] The first differential signal line 20 and the second differential signal line 30 are located on the first surface 11. The first differential signal line 20 and the second differential signal line 30 are arranged side by side in a first direction. The first direction corresponds to the x-axis direction of the drawing.

[0023] The first differential signal line 20 includes: a pair of first signal conductors 21 extending in a second direction intersecting the first direction; and a pair of first ground conductors 22 sandwiching the pair of first signal conductors 21 and arranged along the first signal conductors 21. That is, the first signal conductors 21 and the first ground conductors 22 are arranged to form differential wiring. In other words, the first differential signal line 20 is arranged in the order of the first ground conductor 22, the first signal conductor 21, the first signal conductor 21, and the first ground conductor 22 when viewed from above toward the first surface 11. By arranging the first signal conductor 21 and the first ground conductor 22 to form differential wiring, the wiring substrate 1 is provided with improved noise resistance. In addition, the second direction corresponds to the y-axis direction of the figure. The second direction may be perpendicular to the first direction.

[0024] The second differential signal line 30 includes: a pair of second signal conductors 31 extending in the second direction; and a pair of second ground conductors 32 sandwiching the pair of second signal conductors 31 and arranged along the second signal conductors 31. That is, the second signal conductors 31 and the second ground conductors 32 are arranged as differential wiring. In other words, the second differential signal line 30 is arranged in the order of the second ground conductor 32, the second signal conductor 31, the second signal conductor 31, and the second ground conductor 32 when viewed from above toward the first surface 11. By arranging the second signal conductor 31 and the second ground conductor 32 as differential wiring, the wiring substrate 1 is provided with improved noise resistance.

[0025] The first signal conductor 21 and the second signal conductor 31 extend from the inner side of the first surface 11 to the outer side of the insulating base 10 when viewed from above toward the first surface 11. In this specification, for convenience, the positive side in the y direction is sometimes described as the outer side of the insulating base 10 and the negative side in the y direction is sometimes described as the inner side of the first surface 11.

[0026] The first signal conductor 21 and the second signal conductor 31 are transmission paths for transmitting high-frequency signals. The frequency band of the high-frequency signal can be, for example, 10 to 100 GHz. A lead terminal is connected to the first signal conductor 21 or the second signal conductor 31. The lead terminal connected to the first signal conductor 21 or the second signal conductor 31 functions as a signal terminal. The lead terminal and the first signal conductor 21 or the second signal conductor 31 are joined by a joining material such as solder or brazing material. The lead terminal is a component for electrical connection to an external circuit substrate or the like.

[0027] The shapes of the first signal conductor 21 and the second signal conductor 31 are, for example, rectangular when viewed from above the first surface 11, and may have a width of 0.1 mm to 2 mm along the first direction and a width of 0.3 mm to 10 mm along the second direction. The shapes of the first signal conductor 21 and the second signal conductor 31 are not limited to rectangular, and may be appropriately set together with the width, length, and thickness.

[0028] The first signal conductor 21 and the second signal conductor 31 may be a metallization layer formed on the first surface 11. The metallization layer may include tungsten (W), molybdenum (Mo), manganese (Mn), silver (Ag) or copper (Cu), and may be nickel plated or gold plated. In addition, the metallization layer may include an alloy containing at least one of the above-mentioned metals.

[0029] The first ground conductor 22 and the second ground conductor 32 are conductors having a ground potential. A lead terminal is connected to the first ground conductor 22 or the second ground conductor 32. The lead terminal connected to the first ground conductor 22 or the second ground conductor 32 functions as a ground terminal. The lead terminal and the first ground conductor 22 or the second ground conductor 32 are joined by a joining material such as solder or brazing material.

[0030] The shapes of the first ground conductor 22 and the second ground conductor 32 are, for example, rectangular when viewed from above the first surface 11, and may have a width of 0.1 mm to 2 mm along the first direction and a width of 0.3 mm to 10 mm along the second direction. The shapes of the first ground conductor 22 and the second ground conductor 32 are not limited to rectangular, and may be appropriately set in terms of width, length, and thickness.

[0031] The first ground conductor 22 and the second ground conductor 32 may be a metallization layer formed on the first surface 11. The metallization layer may include tungsten (W), molybdenum (Mo), manganese (Mn), silver (Ag) or copper (Cu), and may be nickel plated or gold plated. In addition, the metallization layer may include an alloy containing at least one of the above-mentioned metals.

[0032] The pair of first ground conductors 22 and the pair of second ground conductors 32 can be connected to other conductors located on the first surface 11 on the negative side of the y-axis direction. As a result, the area that functions as a ground is increased, so that the wiring substrate 1 has stable high-frequency characteristics. When the pair of first ground conductors 22 and the other conductors are connected, and the pair of second ground conductors 32 and the other conductors are connected, the first ground conductors 22 and the second ground conductors 32 can be U-shaped when viewed from above toward the first surface 11. The other conductors can be connected to the ends of the first signal conductor 21 and the second signal conductor 31, which are located on the negative side of the y-axis direction of the wiring substrate 1, when viewed from above toward the first surface 11.

[0033] Furthermore, the mutually adjacent first ground conductor 22 and second ground conductor 32 may be separated or connected to the later-described third ground conductor 50. By integrating the mutually adjacent first ground conductor 22 and second ground conductor 32, the area that functions as the ground of the first ground conductor 22 and the second ground conductor 32 can be increased, thereby achieving a wiring substrate 1 with stable high-frequency characteristics.

[0034] In addition, in this specification, when referring to both the first signal conductor 21 and the second signal conductor 31, for convenience, there are cases where they are described as signal conductors for description, in which case the signal conductors are not marked with reference numerals. In addition, in this specification, when referring to both the first ground conductor 22 and the second ground conductor 32, for convenience, there are cases where they are described as ground conductors for description, in which case the ground conductors are not marked with reference numerals.

[0035] The second recess 15 may be located between a pair of signal conductors. In addition, the third recess 16 may be located between the first signal conductor 21 and the first ground conductor 22, or between the second signal conductor 31 and the second ground conductor 32. The second recess 15 and the third recess 16 are open to the first surface 11. The space formed by the second recess 15 and the third recess 16 can reduce the effective dielectric constant near the signal conductors by electrical insulation, thereby facilitating impedance matching of the wiring substrate 1. By matching the impedance, the wiring substrate 1 can be provided with stable transmission of high-frequency signals.

[0036] The second recess 15 and the third recess 16 may be formed by cutting the insulating base 10 from the first surface 11 to the opposite surface, i.e., the lower surface. In addition, when the insulating base 10 is formed by laminating dielectric materials, the second recess 15 and the third recess 16 may be formed by cutting off the dielectric at the position where the second recess 15 and the third recess 16 are located using a mold, a punch, or a laser, and then laminating the dielectric.

[0037] The second recess 15 and the third recess 16 may be rectangular in shape when viewed from above toward the first surface 11. In addition, the second recess 15 and the third recess 16 may be semicircular or semi-circular in shape when viewed from above toward the first surface 11. Thus, stress concentration on the corners is relieved compared to the case where the second recess 15 and the third recess 16 are rectangular. By relieving stress concentration on the corners, a wiring substrate 1 with fewer cracks is obtained. In addition, when viewed from above toward the first surface 11, the recess 17 may be located at the ends of the second recess 15 and the third recess 16. The recess 17 further reduces the effective dielectric constant near the first signal conductor 21 and the second signal conductor 31, and as a result, impedance matching of the wiring substrate 1 is facilitated. By impedance matching, the wiring substrate 1 with more stable transmission of high-frequency signals is obtained. The recess 17 may be rectangular in shape when viewed from above toward the first surface 11. Furthermore, the depression 17 may be semicircular or semi-circular in plan view toward the first surface 11. This alleviates stress concentration on the corners compared to a case where the depression 17 is rectangular, resulting in a wiring substrate 1 with fewer cracks.

[0038] When viewed from above toward the first surface 11, the first recess 13 may be located at the outer periphery of the insulating base 10 and at the end of the ground conductor. By forming the first recess 13, it is easy to make a structure that makes the ground conductor redundant in the z direction, so that the area that functions as a ground can be increased. By increasing the ground area, the wiring base 1 has improved high-frequency performance.

[0039] The first recess 13 may be located at a position corresponding to the ground conductor in a one-to-one manner. In addition, regarding the first recess 13, one first recess 13 is provided for the first ground conductor 22 and the second ground conductor 32 that are adjacent to each other. By providing one first recess 13 for the first ground conductor 22 and the second ground conductor 32, the first ground conductor 22 and the second ground conductor 32 can be connected by another conductor located in the z direction, thereby achieving a wiring substrate 1 with improved high frequency performance.

[0040] The depth of the first recess 13 in the z-axis direction may be deeper than the depth of the second recess 15 and the third recess 16 in the z-axis direction. Thus, since the area of ​​the ground conductor provided in the first recess 13 in the z-direction can be increased, the area that functions as a ground can be increased. By increasing the area that functions as a ground, impedance matching of the wiring substrate 1 becomes easier. By matching the impedance, the wiring substrate 1 can be provided with stable transmission of high-frequency signals.

[0041] The size of the first recess 13 may be 0.3 mm to 5 mm in width in the x-axis direction, 0.05 mm to 1 mm in width in the y-axis direction, and 0.5 mm to 10 mm in depth in the z-axis direction.

[0042] If you look down from above Figure 1 Formed Figure 3 , or Figure 3 The main part of the enlarged Figure 4 As shown, when viewed from above toward the first surface 11 , the first film 41 is provided so as to straddle between the first ground conductor 22 and the second ground conductor 32 that are adjacent to each other in the second direction.

[0043] In a structure where the ground conductors located at the boundary between the adjacent first differential signal line and the second differential signal line are connected, there is a case where the bonding material is biased when the lead terminal is arranged on the ground conductor. The bias of the bonding material may cause a deviation in the impedance of the input / output terminal.

[0044] In contrast, according to the structure of the present disclosure in which the first film 41 is provided, when the signal conductor or the ground conductor and the lead terminal are connected by the bonding material, the bonding material is blocked at the boundary between the signal conductor or the ground conductor and the first film 41, and the expansion of the bonding material on the first surface 11 can be reduced. Since the variation of the inductance caused by the expansion of the bonding material is reduced by reducing the expansion of the bonding material, it is easy to match the impedance of the wiring substrate 1. By matching the impedance, the wiring substrate 1 becomes stable in the transmission of high-frequency signals. In addition, since a suitable solder foot of the bonding material is formed by reducing the expansion of the bonding material, the bonding strength between the signal conductor or the ground conductor and the lead terminal can be improved and the deviation of the bonding strength can be reduced. In addition, in each figure, in order to make the content clear, the first film 41 and the second film 42, the third film 43, the fourth film 44, and the fifth film 45 described later are represented by diagonal hatching.

[0045] The material of the first film 41 is not limited as long as it is a barrier bonding material. For example, the first film 41 can be made of a ceramic material such as alumina sintered body, mullite sintered body, silicon carbide sintered body, aluminum nitride sintered body, or silicon nitride sintered body, a glass ceramic material, or a chromium material.

[0046] The first film 41 may be a film having lower wettability of the bonding material than the signal conductor and the ground conductor. In the case of such a first film 41, the bonding material is blocked at the boundary between the signal conductor or the ground conductor and the first film 41 due to the difference in wettability.

[0047] The first film 41 can evenly divide the first ground conductor 22 and the second ground conductor 32 adjacent to the first film 41 when viewed from above toward the first surface 11. In other words, the width W1 of the first ground conductor 22 in the first direction and the width W2 of the second ground conductor 32 adjacent to the first ground conductor 22 across the first film 41 can be the same length. By making these widths the same, when the lead terminal is connected to each ground conductor, the bonding material disposed on each ground conductor can be made more uniform, the bonding strength between each ground conductor can be made uniform, and the accuracy of impedance matching can be improved.

[0048] The size of the first film 41 may be such that the width in the first direction is 0.05 mm to 0.5 mm, and the width in the second direction is 0.3 mm to 10 mm.

[0049] Figure 7 Yes Figure 6 The main part of the enlarged figure. Figure 7 As shown, the wiring substrate 1 may include a second film 42 located at the outer periphery of the insulating substrate 10 and at the tip of the signal conductor when viewed from above toward the first surface 11. Since the second film 42 is located at the outer periphery of the insulating substrate 10 and at the tip of the signal conductor, it is possible to reduce the peeling of the signal conductor from the end of the insulating substrate 10. By reducing the occurrence of peeling of the signal conductor, it is possible to provide a wiring substrate 1 with stable transmission of high-frequency signals.

[0050] When the second film 42 is viewed from above toward the first surface 11, the width W3 of the second film 42 in the second direction can be smaller than the width W4 of the first recess 13 in the second direction. When the lead terminal and the signal conductor are joined, a fillet of the joining material is easily formed, and the joining strength of the lead terminal is improved.

[0051] The material of the second film 42 may be the same as that of the first film 41. This can reduce the number of steps required to produce the wiring substrate 1. The second film 42 may have a width of 0.1 mm to 2 mm in the first direction and a width of 0.05 mm to 1 mm in the second direction.

[0052] like Figure 4As shown, the wiring substrate 1 may have a third film 43 located closer to the center of the insulating substrate 10 than the first differential signal line 20 and the second differential signal line 30 when viewed from above the first surface 11. The third film 43 can prevent the bonding material disposed on the signal conductor and the ground conductor from flowing toward the center of the wiring substrate 1. For this reason, when the lead terminal is bonded to the signal conductor and the ground conductor, it is easy to properly arrange the bonding material, and the bonding strength of the lead terminal is stabilized. In addition, the third film 43 may be connected to the first film 41. As a result, since the bonding materials disposed on the adjacent first ground conductor 22 and the second ground conductor 32 do not flow into each other, it is easy to properly arrange the bonding materials to each.

[0053] The material of the third film 43 may be the same as that of the first film 41. This can reduce the number of steps required to manufacture the wiring substrate 1. The third film 43 may have a width of 5 mm to 50 mm in the first direction and a width of 1 mm to 5 mm in the second direction.

[0054] The insulating base 10 may have another conductor having a ground potential, which is disposed closer to the center of the insulating base 10 than the third film 43, on the first surface 11. As a result, the area that functions as a ground is increased, and thus the high-frequency characteristics of the wiring base 1 are stable. The term "closer to the center of the insulating base 10 than the third film 43" means, in other words, being located on the negative side of the y-axis direction compared to the third film 43.

[0055] Figure 5 Yes Figure 3 The main part of the enlarged figure. Figure 5 As shown in FIG. 1 , the wiring substrate 1 may include a fourth film 44. The first differential signal line 20 is disposed closest to the end of the differential signal lines arranged in the first direction on the first surface 11, and the second differential signal line 30 is disposed adjacent to the first differential signal line 20. The fourth film 44 will be described below. The fourth film 44 may be adjacent to the first ground conductor 22 disposed separately from the second ground conductor 32 among the pair of first ground conductors 22 when viewed from above toward the first surface 11. The fourth film 44 may be disposed closer to the outer periphery of the insulating substrate 10 than the first differential signal line 20 in the first direction. Thus, the differential signal line adjacent to the fourth film 44 is only the first differential signal line 20. If there is no differential signal line adjacent to the fourth film 44 other than the first differential signal line 20, the area of ​​the first ground conductor 22 is enlarged in the direction where the fourth film 44 is disposed by providing a bent portion 441 described later. By increasing the area of ​​the first ground conductor 22, the area that functions as a ground increases, thereby facilitating impedance matching of the wiring substrate 1. By matching the impedance, the wiring substrate 1 can achieve stable transmission of high-frequency signals.

[0056] The fourth film 44 may be provided so as to be continuous with the third film 43 and to extend in the second direction. This makes it easy to arrange an appropriate amount of bonding material on the ground conductor, and stabilize the bonding strength of the lead terminal.

[0057] In addition, the shape of the fourth film 44 can be a straight line shape or a curved line shape. Fig. 9 As shown in FIG. 1 , when viewed from above toward the first surface 11, a bent portion 441 may be provided that extends in a direction away from the first signal conductor 21. Alternatively, the bent portion 441 may be provided that extends in a direction away from the first differential signal line 20. The fourth film 44 has the bent portion 441, so that the area of ​​the adjacent first ground conductor 22 can be increased. By increasing the area of ​​the first ground conductor 22, the possibility that the bonding material disposed on the first ground conductor 22 becomes excessive and the bonding material flows into the first recess 13 can be reduced.

[0058] The material of the fourth film 44 may be the same as that of the first film 41. This can reduce the number of steps required to manufacture the wiring substrate 1. The fourth film 44 may have a width of 0.1 mm to 2 mm in the first direction and a width of 0.3 mm to 10 mm in the second direction.

[0059] The insulating base 10 may have another conductor having a ground potential provided closer to the outer periphery of the insulating base 10 than the fourth film 44 in the first direction on the first surface 11. This increases the area functioning as a ground, thereby achieving a wiring base 1 with stable high frequency characteristics.

[0060] Figure 8 Yes Figure 6 The main part of the enlarged figure. Figure 8 As shown in the figure, the wiring substrate 1 may have a fifth film 45 located at the periphery of the signal conductor and extending in the second direction when viewed from above toward the first surface 11. Since the fifth film 45 is located at the periphery of the signal conductor and extending in the second direction, it is possible to reduce the peeling of the signal conductor from the end of the insulating substrate 10 along the second direction. By reducing the occurrence of peeling of the signal conductor, it is possible to produce a wiring substrate 1 with stable transmission of high-frequency signals.

[0061] Furthermore, the fifth film 45 may be connected to the second film 42 and extend in the second direction. Thus, since the fifth film 45 and the second film 42 are continuously located at the end of the signal conductor, the occurrence of separation of the signal conductor can be further reduced.

[0062] The material of the fifth film 45 may be the same as that of the first film 41. This can reduce the number of steps required to manufacture the wiring substrate 1. The size of the fifth film 45 may be 0.02 mm to 0.5 mm in width in the first direction and 0.1 mm to 2 mm in width in the second direction.

[0063] The insulating base 10 may include a mounting portion 12 as a portion for mounting the first surface 11 and the electronic component 101. In other words, the mounting portion 12 may be integral with the insulating base 10. When the insulating base 10 includes the mounting portion 12, the mounting portion 12 may be a surface located on the first surface 11 or a surface located on the opposite side of the first surface 11. Figure 2 , a wiring substrate 1 in which a mounting portion 12 and an insulating substrate 10 are integrated is disclosed. Alternatively, the mounting portion 12 may be located on a substrate separate from the insulating substrate 10.

[0064] like Fig.10 As shown, the third grounding conductor 5 may be located between the first surface 11 and the first film 41, the second film 42, the third film 43, the fourth film 44 or the fifth film 45. In other words, the first film 41, the second film 42, the third film 43, the fourth film 44 or the fifth film 45 may be located on the third grounding conductor 50. The third grounding conductor 50 is connected to the first grounding conductor 22 and the second grounding conductor 32. By providing the third grounding conductor 50, the area of ​​the differential signal line that functions as a ground can be increased, thereby achieving a wiring substrate 1 with stable transmission of high-frequency signals. In addition, Fig.10 In order to make the content clear, the third ground conductor 50 is represented by dotted hatching.

[0065] The shape of the third ground conductor 50 may be the same as the shape of the first film 41 , the second film 42 , the third film 43 , the fourth film 44 , or the fifth film 45 located on the third ground conductor 50 .

[0066] The third ground conductor 50 may be a metallization layer formed on the first surface 11. The metallization layer may include tungsten (W), molybdenum (Mo), manganese (Mn), silver (Ag) or copper (Cu), and may be nickel plated or gold plated. In addition, the metallization layer may include an alloy containing at least one of the above-mentioned metals.

[0067] The substrate may be, for example, rectangular in plan view, and may have a size of 5 mm×10 mm to 50 mm×50 mm in plan view.

[0068] The substrate may include, for example, a metal such as iron (Fe), copper (Cu), nickel (Ni), chromium (Cr), cobalt (Co), molybdenum (Mo) or tungsten (W), or an alloy of these metals. When the substrate includes a metal material, the substrate can be made by a metal processing method such as a rolling process and a punching process on an ingot of the metal material. In addition, the substrate may include a dielectric material. As a dielectric material, for example, a ceramic material such as an alumina sintered body, a mullite sintered body, a silicon carbide sintered body, an aluminum nitride sintered body or a silicon nitride sintered body, or a glass ceramic material can be used. When the substrate includes a dielectric material, nickel plating or gold plating may be provided on the surface of the substrate. By providing nickel plating or gold plating on the surface of the substrate, the substrate improves the wettability, corrosion resistance and weather resistance of the bonding material.

[0069] The insulating base 10 may include a frame 14 surrounding the position of the mounting portion 12. When the insulating base 10 and the mounting portion 12 are integral, the frame 14 may be integral with the insulating base 10. In addition, when the insulating base 10 and the mounting portion 12 are separate, the frame 14 may be separate from the insulating base 10. Figure 2 2 discloses a wiring substrate 1 in which a frame portion 14 and an insulating substrate 10 are integrated.

[0070] The frame portion 14 may be rectangular or U-shaped in a plan view, and may have a size of 5 mm×10 mm to 50 mm×50 mm, a height of 2 mm to 15 mm, and a thickness of 0.5 mm to 2 mm.

[0071] The frame 14 may include, for example, a metal such as iron (Fe), copper (Cu), nickel (Ni), chromium (Cr), cobalt (Co), molybdenum (Mo) or tungsten (W), or an alloy of these metals. When the frame 14 includes a metal material, the frame 14 can be made by subjecting an ingot of the metal material to a metal processing method such as a rolling process or a punching process. In addition, the frame 14 may include a dielectric material. As a dielectric material, for example, a ceramic material such as an alumina sintered body, a mullite sintered body, a silicon carbide sintered body, an aluminum nitride sintered body or a silicon nitride sintered body, or a glass ceramic material can be used. When the frame 14 includes a dielectric material, nickel plating or gold plating may be provided on the surface of the frame 14. By providing nickel plating or gold plating on the surface of the frame 14, the frame 14 improves the wettability, corrosion resistance and weather resistance of the bonding material.

[0072] When the mounting portion 12 and the frame 14 are separated from the insulating base 10, the joint that can fit the wiring base 1 is located on the side wall of the frame 14. The joint can penetrate the inside and outside of the frame 14 along the mounting surface of the mounting portion 12 where the electronic component 101 is mounted.

[0073] The insulating substrate 10 may include other conductors between the insulating layers. For example, when performing a planar perspective toward the first surface 11, the other conductors between the insulating layers may be located around the first recess 13, around the second recess 15, around the third recess 16, at a position overlapping with the signal conductor, and at a position overlapping with the ground conductor. Furthermore, with respect to the other conductors between the insulating layers, the other conductors between the insulating layers may be electrically connected to each other by the first recess 13, the second recess 15, the third recess 16, or via conductors. In addition, the other conductors between the insulating layers may be connected to the signal conductor, the ground conductor, or other conductors located on the first surface 11 through via conductors. In the case where the conductors between the insulating layers are connected to the signal conductor and the ground conductor through via conductors, it is necessary to configure other conductors connected thereto respectively so that the signal conductor and the ground conductor will not be short-circuited. In addition, in this specification, the so-called planar perspective refers to perspective toward an arbitrary plane, which is sometimes used to illustrate the positional relationship of objects with different depths.

[0074] <Structure of Electronic Device 100>

[0075] Fig.11 The electronic device 100 shown in the figure includes a wiring substrate 1 and an electronic component 101. Fig.12 The electronic device 100 shown further includes a cover 102 .

[0076] The electronic component 101 may be, for example, a capacitor, an optical semiconductor such as LD (Laser diode) or PD (PhotoDiode), a light emitting element such as LED (Light Emitting Diode), or an integrated circuit such as LSI (Large Scale Integration).

[0077] Electronic component 101 The electronic component 101 is mounted on the mounting portion 12. The electronic component 101 is electrically connected to the wiring substrate 1 by, for example, a bonding wire or a flip chip.

[0078] The cover 102 can be located above the frame 14 and cover the electronic device 100. In this case, the cover 102 can seal the electronic device 100. The cover 102 can be rectangular when viewed from above toward the first surface 11. In the case of a rectangular shape, the size can be 5mm×10mm~50mm×50mm, and the thickness can be 0.5mm~2mm. The cover 102 can include, for example, a metal such as iron (Fe), copper (Cu), nickel (Ni), chromium (Cr), cobalt (Co), molybdenum (Mo) or tungsten (W), or an alloy of these metals. The metal component constituting the cover 102 can be manufactured by subjecting an ingot of such a metal material to a metal processing method such as a rolling method and a punching method.

[0079] <Method for Manufacturing Wiring Substrate 1 and Electronic Device 100>

[0080] Next, an example of a method for manufacturing the wiring substrate 1 and the electronic device 100 according to an embodiment of the present disclosure will be described. In addition, in this specification, an example of a method for manufacturing the wiring substrate 1 in which the wiring substrate 1, the mounting portion 12, and the frame portion 14 are integrated will be described.

[0081] (1) First, a suitable organic binder and solvent are added to raw material powders such as aluminum oxide and silicon oxide, and then mixed to prepare a slurry. Next, the prepared slurry is subjected to a forming method such as a scraper method to be formed into a thin sheet to prepare a plurality of ceramic green sheets. At this time, a notch to become the first recess 13, the second recess 15 or the third recess 16 can be provided at a given position of the ceramic green sheet. It is also possible to provide a notch at a given position of the ceramic green sheet using a mold, a punch or a laser when providing the first recess 13, the second recess 15, the third recess 16, the depression 17, the mounting portion 12 or the frame portion 14.

[0082] (2) Next, a metal paste is applied to the ceramic green sheet obtained in step (1) by screen printing or the like to form the first differential signal line 20, the second differential signal line 30, the third ground conductor 50 and other conductors. The metal paste is prepared by adding a suitable solvent and a binder to a metal powder containing the above-mentioned metal material and mixing them to adjust the viscosity to a suitable level. In addition, the metal paste may also contain glass or ceramics to improve the bonding strength with the insulating substrate 10. In the case of providing a via conductor, in step (1), a through hole is provided at a given position of the ceramic green sheet, and the through hole is filled with the metal paste forming the first differential signal line 20, the second differential signal line 30 and other conductors.

[0083] (3) The plurality of ceramic green sheets described above are stacked and then pressurized.

[0084] (4) Next, the stacked ceramic green sheets are fired at a temperature of about 1600° C. in a reducing atmosphere, and cut or punched into an appropriate shape to produce an insulating base 10 of a desired shape. In the step (1), by providing a notch to become the first recess 13, the second recess 15, the third recess 16, the depression 17, the mounting portion 12, or the frame portion 14, the first recess 13, the second recess 15, the third recess 16, the depression 17, the mounting portion 12, or the frame portion 14 can be produced after firing. In addition, if the metal paste is applied or filled in the above-mentioned portions in (2), the first differential signal line 20, the second differential signal line 30, the third ground conductor 50, other conductors, or the via conductor can be produced by going through the step (4).

[0085] (5) Next, the surface of the insulating base 10 prepared in (4) is subjected to a treatment such as plating. Nickel plating or gold plating may also be provided on the surface. By providing nickel plating or gold plating on the surface, the insulating base 10 improves the wettability, corrosion resistance, and weather resistance of the bonding material.

[0086] (6) Next, the first film 41 , the second film 42 , the third film 43 , the fourth film 44 , and the fifth film 45 are processed on the surface of the insulating base 10 .

[0087] (7) Next, the electronic component 101 is mounted on the mounting portion 12. The electronic component 101 is electrically bonded to the wiring substrate 1 by wire bonding or the like. In this case, the electronic component 101 may be fixed to the mounting portion 12 by providing an adhesive or the like on the mounting portion 12. In addition, the electronic device 100 and the cover 102 may be bonded using a bonding material after the electronic component 101 is mounted on the mounting portion 12.

[0088] By manufacturing wiring substrate 1 through the above steps (1) to (7), and mounting electronic component 101 on mounting portion 12 of wiring substrate 1, electronic device 100 can be manufactured. The order of the above steps (1) to (7) and the number of steps are not specified.

[0089] As described above, the wiring substrate 1 and the electronic device 100 of the present disclosure are not limited to the above-mentioned embodiments, and various modifications can be made without departing from the gist of the present disclosure. Furthermore, all modifications within the scope of the claims are within the scope of the present disclosure.

[0090] Possibility of industrial application

[0091] The present disclosure can be utilized in a wiring substrate and an electronic device.

[0092] Description of Reference Numerals

[0093] 1: Wiring substrate

[0094] 10: Insulation substrate

[0095] 11: Page 1

[0096] 12: Loading part

[0097] 13: 1st concave part

[0098] 14: Frame

[0099] 15: 2nd concave part

[0100] 16: 3rd concave part

[0101] 17: Depression

[0102] 20: 1st differential signal line

[0103] 21: 1st signal conductor

[0104] 22: 1st ground conductor

[0105] 30: Second differential signal line

[0106] 31: Second signal conductor

[0107] 32: Second ground conductor

[0108] 41: The 1st film

[0109] 42: The 2nd film

[0110] 43: The 3rd film

[0111] 44: The 4th film

[0112] 45: The 5th film

[0113] 50: 3rd ground conductor

[0114] 100: Electronic devices

[0115] 101: Electronic components

[0116] 102: Cover

Claims

1. A wiring substrate, characterized in that: have: An insulating substrate having a first surface; a first differential signal line located on the first surface; a second differential signal line located on the first surface and arranged in a first direction with the first differential signal line, The first differential signal line has: a pair of first signal conductors extending in a second direction intersecting the first direction; and a pair of first ground conductors sandwiching the pair of first signal conductors and arranged along the first signal conductors, The second differential signal line has: a pair of second signal conductors extending in the second direction; and a pair of second ground conductors sandwiching the pair of second signal conductors and arranged along the second signal conductors, The first film is provided so as to extend between the first ground conductor and the second ground conductor adjacent to each other in the second direction when viewed from above toward the first surface. The insulating base has a first recessed portion located at an outer periphery of the insulating base and at a tip of the first ground conductor in the plan view.

2. The wiring substrate according to claim 1, characterized in that A width W1 of the first ground conductor adjacent to the first film in the first direction and a width W2 of the second ground conductor adjacent to the first ground conductor via the first film in the first direction are the same length.

3. The wiring substrate according to claim 1, characterized in that: The wiring substrate includes: a third ground conductor located between the first surface and the first film; The third ground conductor is connected to the first ground conductor and the second ground conductor.

4. The wiring substrate according to claim 2, characterized in that: In the plan view, the second film is located on the outer periphery of the insulating base and on the tip of the first signal conductor.

5. The wiring substrate according to claim 4, characterized in that: The material of the second film is the same as that of the first film.

6. The wiring substrate according to claim 4, characterized in that: Regarding the second film, a width W3 in the second direction when viewed in the plan view is smaller than a width W4 of the first recessed portion in the second direction when viewed in the plan view.

7. The wiring substrate according to any one of claims 1 to 6, characterized in that: The wiring substrate includes a third film which is provided closer to the center of the insulating substrate than the first differential signal line and the second differential signal line in the plan view and which is connected to the first film.

8. The wiring substrate according to claim 7, characterized in that: The wiring substrate includes a fourth film that is adjacent to the first ground conductor that is disposed farther from the second ground conductor among the pair of first ground conductors and that extends from the third film in the second direction when viewed from above.

9. The wiring substrate according to claim 8, characterized in that: The fourth film is provided closer to the outer periphery of the insulating base than the first differential signal line in the first direction.

10. The wiring substrate according to claim 8 or 9, characterized in that: The fourth film has a curved portion when viewed in the plan view.

11. The wiring substrate according to claim 10, characterized in that: The bent portion extends in a direction away from the first signal conductor.

12. The wiring substrate according to any one of claims 4 to 6, characterized in that: The wiring substrate includes a fifth film located at an outer periphery of the first signal conductor and extending from the second film in the second direction when viewed from above.

13. An electronic device, characterized in that: have: The wiring substrate according to any one of claims 1 to 12; and An electronic component is connected to the wiring substrate.

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