Wiring substrate, electronic device, and electronic module

Abstract

The wiring substrate comprises: an insulating substrate having a first surface, which is square in shape when the first surface is viewed from above, and has a mounting portion for electronic components on the first surface; a via conductor located in the insulating substrate and located at a corner when viewed from above, and extending along the thickness direction of the insulating substrate; a wiring conductor located on the first surface, connecting the mounting portion and the via conductor; and a heat dissipation portion located in the insulating substrate and located at a position overlapping with the mounting portion when viewed from above, and the first surface has a first area surrounded by the wiring conductor when viewed from above, between the heat dissipation portion and the via conductor when viewed from above.

Description

Technical Field

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

[0002] Conventionally, there is known a wiring board in which electronic components are mounted on the main surface of an insulating substrate made of ceramic.

[0003] The above-mentioned wiring substrate comprises: an insulating substrate having a notch portion which is open on the main surface and the side surface and is longer in the side direction; an inner surface electrode which is located on the inner surface of the notch portion; and a wiring conductor which is connected to the inner surface electrode and is arranged on the surface and inside of the insulating substrate (refer to Japanese Patent Gazette No. 2013-232610). Summary of the invention

[0004] The wiring substrate disclosed in the present invention comprises: an insulating substrate having a first surface which is square in shape when the first surface is viewed from above, and having a mounting portion for electronic components on the first surface; a via conductor which is located in the insulating substrate and is located at a corner when viewed from above, and extends along the thickness direction of the insulating substrate; a wiring conductor which is located on the first surface and connects the mounting portion and the via conductor; and a heat dissipation portion which is located in the insulating substrate and is located at a position overlapping with the mounting portion when viewed from above, and the first surface has a first area which is surrounded by the wiring conductor when viewed from above, between the heat dissipation portion and the via conductor when viewed from above.

[0005] The electronic device of the present disclosure includes an electronic component in the mounting portion of the wiring substrate having the above-described structure.

[0006] The electronic module disclosed in the present invention comprises: a module substrate; and an electronic device having the above-mentioned structure connected to the module substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 (a) is a top view showing the electronic device in the first embodiment, and (b) is a bottom view of (a).

[0008] Figure 2 yes Figure 1 FIG. 1 is a top view of the interior of a wiring substrate in the electronic device shown.

[0009] Figure 3 (a) is Figure 1 (a) is a cross-sectional view of the electronic device at line AA, (b) is Figure 1 (a) is a cross-sectional view of the electronic device at line BB, (c) is Figure 1 (a) is a cross-sectional view of the electronic device taken along line CC.

[0010] Figure 4(a) is a top view showing an electronic device according to a second embodiment, and (b) is a bottom view of (a).

[0011] Figure 5 yes Figure 4 FIG. 1 is a top view of the interior of a wiring substrate in the electronic device shown.

[0012] Figure 6 (a) is Figure 4 (a) is a cross-sectional view of the electronic device at line AA, (b) is Figure 4 (a) is a cross-sectional view of the electronic device at line BB, (c) is Figure 4 (a) is a cross-sectional view of the electronic device taken along line CC.

[0013] Figure 7 (a) is a top view showing the electronic device in the third embodiment, and (b) is a bottom view of (a).

[0014] Figure 8 yes Figure 7 FIG. 1 is a top view of the interior of a wiring substrate in the electronic device shown.

[0015] Fig. 9 (a) is Figure 7 (a) is a cross-sectional view of the electronic device at line AA, (b) is Figure 7 (a) is a cross-sectional view of the electronic device at line BB, (c) is Figure 7 (a) is a cross-sectional view of the electronic device taken along line CC.

[0016] Fig.10 (a) is a top view showing an electronic device according to a fourth embodiment, and (b) is a bottom view of (a).

[0017] Fig.11 yes Fig.10 FIG. 1 is a top view of the interior of a wiring substrate in the electronic device shown.

[0018] Fig.12 (a) is Fig.10 (a) is a cross-sectional view of the electronic device at line AA, (b) is Fig.10 (a) is a cross-sectional view of the electronic device at line BB, (c) is Fig.10 (a) is a cross-sectional view of the electronic device taken along line CC. DETAILED DESCRIPTION

[0019] Several exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0020] (First embodiment)

[0021] like Figure 1 to Figure 3 As shown, the wiring substrate 1 in the first embodiment includes: an insulating substrate 11; a via conductor 14, both ends of which are located along the thickness direction of the insulating substrate; and a wiring conductor 15, which is located on the surface and inside of the insulating substrate 11. The wiring substrate 1 has a mounting portion 11a when viewed from above, and the mounting portion 11a is used to mount an electronic component 2 in the center. The electronic device includes the wiring substrate 1 and the electronic component 2 mounted on the mounting portion 11a of the wiring substrate 1. The electronic device is connected to a connection pad on a module substrate constituting an electronic module using, for example, a bonding material.

[0022] The wiring substrate 1 in this embodiment comprises: an insulating substrate 11 having a first surface (main surface) which is square in shape when the first surface is viewed from above, and having a mounting portion 11a for the electronic component 2 on the first surface; a via-hole conductor 14 which is located in the insulating substrate 11 and is located at a corner when viewed from above, and extends in the thickness direction of the insulating substrate 11; a wiring conductor 15 which is located on the first surface and connects the mounting portion 11a and the via-hole conductor 14; a heat dissipation portion 17 which is located in the insulating substrate 11 and is located at a position overlapping with the mounting portion 11a when viewed from above, and the first surface has a first region 15a which is surrounded by the wiring conductor 15 when viewed from above, and is located between the heat dissipation portion 17 and the via-hole conductor 14 when viewed from above. Figure 1 to Figure 3 In the above description, the upward direction refers to the positive direction of the imaginary z-axis. In the following description, the distinction between up and down is for convenience of description, and does not limit the up and down when the wiring substrate 1 is actually used.

[0023] The surface electrode 13 is Figure 1 as well as Figure 2 In the example shown, the via conductor 14 is shown by hatching. Figure 1 as well as Figure 2 In the example shown, the area where the side surface of the via conductor 14 overlaps with the wiring conductor 15 is indicated by a dotted line. Figure 1 as well as Figure 2 In the example shown, this is indicated by shading.

[0024] The insulating substrate 11 has a first surface ( Figure 1 to Figure 3 The second surface (side surface) connected to the first surface, and the third surface (on the side opposite to the first surface in the thickness direction) Figure 1 to Figure 3 The insulating substrate 11 includes a plurality of insulating layers, and has a square shape when viewed from above, that is, when viewed from a direction perpendicular to the first surface. The insulating substrate 11 functions as a support for supporting the electronic component 2. The insulating substrate 11 has a mounting portion 11a in the center portion when viewed from above, and the mounting portion 11a is used to mount the electronic component 2 on the first surface side.

[0025] The insulating substrate 11 can use ceramics such as alumina sintered body (alumina ceramics), aluminum nitride sintered body, silicon nitride sintered body, mullite sintered body or glass ceramic sintered body. For example, in the case of the insulating substrate 11 being an alumina sintered body, a slurry is prepared by adding and mixing a suitable organic binder and a solvent to raw material powders such as aluminum oxide (Al2O3), silicon oxide (SiO2), magnesium oxide (MgO), and calcium oxide (CaO). The slurry is formed into a sheet by a known scraper method or a calendering roll method, thereby preparing a ceramic green sheet. Next, the ceramic green sheet is subjected to appropriate stamping processing, and a plurality of ceramic green sheets are stacked to form a resulting body, and the resulting body is fired at a high temperature (about 1400°C) to prepare the insulating substrate 11.

[0026] The recess 12 is opened on the side surface of the insulating substrate 11 at the third surface and the second surface of the insulating substrate 11, and is arranged to be located at the side. Figure 1 as well as Figure 2 As shown in the example, the recess 12 is formed into a rectangular shape with arc-shaped corners when viewed from above. In addition, the recess 12 can be a semi-elliptical shape or a semi-circular shape, or a rectangular shape with multiple height differences when viewed from above. The recess 12 is formed to be long along the side direction of the insulating substrate 11, and the width is greater than the depth. Figure 1 to Figure 3 As shown in the example, the recess 12 may be provided from the first surface to the second surface and the third surface of the insulating substrate 11, or may be provided from the middle of the second surface of the insulating substrate 11 to the first surface or the third surface. The recess 12 is formed by forming through holes that become the recess 12 in a plurality of ceramic green sheets for the insulating substrate 11 by laser processing or die punching.

[0027] like Figure 1 to Figure 3 As shown in the example, the surface electrode 13 is located on the inner surface of the recess 12 and is located along the thickness direction of the insulating substrate 11. The via conductor 14 is located on the corner side of the insulating substrate 11 and is located along the thickness direction of the insulating substrate 11. The wiring conductor 15 is located on the first surface and the second surface and inside the insulating substrate 11. The surface electrode 13 and the via conductor 14 are electrically connected to the wiring conductor 15. The surface electrode 13, the via conductor 14 and the wiring conductor 15 are used to electrically connect the electronic component 2 mounted on the wiring substrate 1 and the external module substrate.

[0028] The surface electrode 13, the via conductor 14, and the wiring conductor 15 are metallized materials (metalized) including metal powders such as tungsten (W), molybdenum (Mo), manganese (Mn), silver (Ag), and copper (Cu). When using a high melting point metal material such as W or Mo, for example, it can also be mixed or alloyed with Cu for use.

[0029] The surface electrode 13 or the wiring conductor 15 is formed by printing and applying a metal paste for the surface electrode 13 or the wiring conductor 15 on a ceramic green sheet for the insulating substrate 11 by a printing method such as screen printing, and firing the metal paste together with the ceramic green sheet for the insulating substrate 11. In addition, a through hole for the via conductor 14 is formed on the ceramic green sheet for the insulating substrate 11 by a processing method such as a punching process or a laser process using a mold or a punch, and the metal paste for the via conductor 14 is filled in the through hole by the above-mentioned printing method, and fired together with the ceramic green sheet for the insulating substrate 11, thereby forming the via conductor 14. A suitable solvent and a binder are added to the above-mentioned metal powder and kneaded to adjust to a moderate viscosity, thereby preparing a metal paste. In addition, in order to improve the bonding strength with the insulating substrate 11, the metal paste may also contain glass powder or ceramic powder.

[0030] When looking from above, Figure 1 as well as Figure 2 As shown in the example, the wiring conductor 15 surrounding the area between the heat dissipation portion 17 and the via conductor 14 has a first area 15a. The wiring conductor 15 is not arranged in the first area 15a. The first area 15a is located on the imaginary straight line M connecting the heat dissipation portion 17 and the via conductor 14 when viewed from above. The first area 15a of the wiring conductor 15 can be formed by not applying the metal paste for the wiring conductor 15 to the first area 15a when printing and applying the metal paste for the wiring conductor 15 on the ceramic green sheet for the insulating substrate 11 by printing means such as screen printing.

[0031] The heat dissipation portion 17 can be made of: a material having a higher thermal conductivity than the insulating substrate 11, such as a metal material such as copper (Cu), copper-tungsten (Cu-W) or aluminum (Al); a ceramic material such as an alumina sintered body, a mullite sintered body, an aluminum nitride sintered body or a silicon carbide sintered body. For example, when the insulating substrate 11 is made of an alumina sintered body, by setting the material of the heat dissipation portion 17 to Cu-W and using a material having a higher thermal conductivity than the insulating substrate 11 in the heat dissipation portion 17, the heat generated by the electronic component 2 mounted on the mounting portion 11a of the insulating substrate 11 can be well dissipated through the heat dissipation portion 17, thereby making it possible to provide a wiring substrate 1 with excellent heat dissipation. In addition, by bonding the lower surface of the heat dissipation portion 17 to a conductor or the like of a module substrate, the heat dissipation of the electronic device can be improved.

[0032] The heat dissipation portion 17 discharges heat generated by the electronic component 2 mounted on the wiring substrate 1 to the outside of the wiring substrate 1 to improve the heat dissipation of the wiring substrate 1 , and may be a metal body or a heat dissipation conductor group. Figure 1 to Figure 3 The heat sink 17 in the illustrated example shows a metal body.

[0033] The upper end and the lower end of the heat dissipation portion 17 are located along the thickness direction of the insulating substrate 11. The heat dissipation portion 17 has a round columnar shape. The heat dissipation portion 17 is formed at a position overlapping with the mounting portion 11a of the electronic component 2 when viewed from above. The heat dissipation portion 17 contains Cu—W as a main component.

[0034] After holes are formed in the ceramic green sheet for insulating substrate 11 by punching or laser processing using a die or punching, metal paste for heat dissipation portion 17 or a metallized sheet for heat dissipation portion 17 is placed in the formed holes, thereby manufacturing heat dissipation portion 17.

[0035] The heat dissipation part 17 is composed of a metal powder metallized material containing CuW as a main component. The metal powder can also be in any form of a mixture or an alloy. For example, the heat dissipation part 17 is made by printing and filling the holes formed in the ceramic green sheet with a metal paste using a screen printing method, etc. The metal paste is made by adding an organic binder and an organic solvent to the metal powder of W and the metal powder of Cu, and further adding a dispersant as needed. Alternatively, it can be made by filling the holes formed in the ceramic green sheet with a metallized sheet for the heat dissipation part 17. Among the components constituting the heat dissipation part 17, the content of CuW as the main component is the largest. In addition, among the components constituting the heat dissipation part 17, it can contain more than 50% by mass of CuW, or it can contain more than 80% by mass of CuW.

[0036] In addition, if Figure 2 as well as Figure 3 As shown in the example, the metal layer 18 may be arranged along the upper and lower ends of the heat dissipation portion 17 in the thickness direction of the insulating substrate 11 so as to overlap with the heat dissipation portion 17 in a plan view. The metal layer 18 may also contain CuW as a main component, similarly to the heat dissipation portion 17.

[0037] The metal paste for the metal layer 18 formed by the same method as the heat dissipation portion 17 is printed by screen printing or the like so as to overlap with the metal paste for the heat dissipation portion 17 buried in the ceramic green sheet, thereby producing the metal layer 18. In addition, among the components constituting the metal layer 18, CuW may be contained in an amount of 50% by mass or more, or 80% by mass or more.

[0038] The surface of the surface electrode 13 and the wiring conductor 15 exposed from the insulating substrate 11 is coated with a metal plating layer by electroplating or electroless plating. The metal plating layer includes a metal such as nickel, copper, gold or silver that has excellent corrosion resistance and connection property to the connecting member, for example, a nickel plating layer with a thickness of 0.5 to 5 μm and a gold plating layer with a thickness of 0.1 to 3 μm are sequentially coated. By the above, the corrosion of the surface electrode 13 and the wiring conductor 15 can be effectively suppressed, and the connection between the wiring conductor 15 and the connecting member 3 such as the welding wire and the connection between the surface electrode 13 and the wiring conductor 15 and the connection pad formed on the module substrate can be firmly bonded.

[0039] In addition, the metal plating layer is not limited to the nickel plating layer / the gold plating layer, and may be other metal plating layers including the nickel plating layer / the palladium plating layer / the gold plating layer.

[0040] An electronic device can be manufactured by mounting an electronic component 2 on a mounting portion 11a located in the center of a wiring substrate 1. The electronic component 2 mounted on the wiring substrate 1 is a semiconductor element such as an IC chip or an LSI chip, a CCD (Charge Coupled Device) type, a CMOS (Complementary Metal Oxide Semiconductor) type, or other imaging element, a LD (Laser Diode), a LED (Light Emitting Diode) or other light-emitting element, or a PD (Photo Diode) or other light-receiving element. For example, in the case where the electronic component 2 is a flip-chip type electronic component 2, the electronic component is mounted on the wiring substrate 1 by electrically and mechanically connecting the electrodes of the electronic component 2 and the wiring conductor 15 via a connecting member 3 such as a solder bump, a gold bump, or a conductive resin (anisotropic conductive resin, etc.). Furthermore, for example, when the electronic component 2 is a wire-bonded semiconductor element, the semiconductor element is fixed to the mounting portion 11a of the wiring substrate 1 by a bonding member such as a low-melting-point solder material or a conductive resin, and then the electrodes of the semiconductor element and the wiring conductor 15 are electrically connected via a connecting member 3 such as a bonding wire, thereby being mounted on the wiring substrate 1. As described above, the electronic component 2 is electrically connected to the wiring conductor 15.

[0041] In addition, a plurality of electronic components 2 may be mounted on the mounting portion 11a of the wiring substrate 1, and other components such as small electronic components such as resistors and capacitors, and mirrors may be mounted around the electronic components 2 as needed. When a plurality of electronic components 2 are mounted on the mounting portion 11a of the wiring substrate 1, the region surrounding the plurality of electronic components 2 when viewed from above may be considered as the mounting portion 11a. In addition, the electronic components 2 may be sealed using a sealing material including resin or glass, or by a cover including resin, glass, ceramic, or metal, etc. as needed.

[0042] The wiring conductor of the electronic device of this embodiment is connected to the connection pad of the module substrate via solder, for example, to form an electronic module. The surface electrode 13 of the electronic device located on the inner surface of the recess 12 and the wiring conductor 15 located on the lower surface of the wiring substrate are connected to the connection pad of the module substrate.

[0043] According to the wiring substrate of the present embodiment, there is an insulating substrate 11 having a first surface which is square in shape when the first surface is viewed from above and has a mounting portion 11a for the electronic component 2 on the first surface; a via conductor 14 which is located in the insulating substrate 11 and is located at a corner when viewed from above and extends in the thickness direction of the insulating substrate 11; a wiring conductor 15 which is located on the first surface and connects the mounting portion 11a and the via conductor 14; a heat dissipation portion 17 which is located in the insulating substrate 11 and is configured to overlap with the mounting portion 11a when viewed from above, and the first surface has a first region 15a which is surrounded by the wiring conductor 15 when viewed from above and is between the heat dissipation portion 17 and the via conductor 14 when viewed from above. Through the above-mentioned structure, the heat of the electronic component 2 that conducts heat through the wiring conductor 15 can be suppressed from being conducted to the via conductor 14, and it becomes easy to conduct heat through the heat dissipation portion 17. When heat and current are applied to the wiring conductor 15 and the via conductor 14 and used for a long period of time, the disconnection at the connection between the wiring conductor 15 and the via conductor 14 can be suppressed.

[0044] Furthermore, when viewed from above, if the first region 15a of the wiring conductor 15 is located closer to the via-hole conductor 14 than the heat dissipation portion 17, it is possible to suppress the heat of the electronic component 2 that is conducted through the wiring conductor 15 from being conducted to the via-hole conductor 14, making it easier for the heat to be conducted through the heat dissipation portion 17. When heat and current are applied to the wiring conductor 15 and the via-hole conductor 14 and the wiring conductor 15 and the via-hole conductor 14 are used for a long period of time, it is possible to suppress the wiring conductor 15 and the via-hole conductor 14 from being broken at the connection portion.

[0045] In addition, if Figure 1As in the example shown in (a), when viewed from above, if the first region 15a is smaller than the heat dissipation portion 17 (W2 < W1) with respect to the respective distances in the direction perpendicular to the imaginary straight line M connecting the central portion of the via-hole conductor 14 and the central portion of the heat dissipation portion 17, it becomes easier to arrange the first region 15a on the via-hole conductor 14 side, and effectively suppress the heat of the electronic component 2 that is conducted through the wiring conductor 15 from being conducted to the via-hole conductor 14, and it becomes easier to conduct heat through the heat dissipation portion 17, and when heat and current are applied to the wiring conductor 15 and the via-hole conductor 14 and used for a long period of time, it is possible to suppress the disconnection of the wiring conductor 15 and the via-hole conductor 14 at the connection portion. In addition, as described later, Figure 5 When a plurality of via-hole conductors 14 are provided as in the illustrated example, the central portion of the via-hole conductor 14 described above is provided as the central portion of the plurality of via-hole conductors 14 .

[0046] Furthermore, when viewed from above, if the wiring conductor 15 is located in the area on the corner side of the insulating substrate 11 where the via conductor 14 is located, even if the heat of the electronic component 2 is conducted toward the via conductor 14 through the wiring conductor 15, it will be conducted toward the area sandwiched by the two sides of the wiring conductor 15 on the corner side of the insulating substrate 11, thereby further suppressing the conduction to the via conductor 14 and making it easier to conduct heat through the heat dissipation portion 17. When heat and current are applied to the wiring conductor 15 and the via conductor 14 and they are used for a long period of time, it is possible to suppress the wiring conductor 15 and the via conductor 14 from being disconnected at the connection portion.

[0047] Furthermore, if a via conductor 14 (a second via conductor), a wiring conductor 15 (a first wiring conductor), and a second region 15a are arranged on the opposite side of the via conductor 14 (a first via conductor), the wiring conductor 15 (a first wiring conductor), and the heat dissipation portion 17 in the first region 15a, the respective via conductors 14 (a first via conductor and a second via conductor) are located away from each other, thereby suppressing heat conduction of the electronic component 2 through the wiring conductor 15 to the respective via conductors 14, and suppressing wire breakage at the connection portion between the wiring conductor 15 and the via conductor 14 when used for a long period of time.

[0048] In addition, the insulating substrate 11 has a recess 12 on the second surface connected to the first surface, and the recess 12 has a surface electrode 13. If the wiring conductor 15 is connected to the surface electrode 13 in addition to the mounting portion 11a and the via conductor 14, the heat of the electronic component 2 which is heat-conducted via the wiring conductor 15 is conducted through the heat dissipation portion 17 and also conducted to the surface electrode 13, thereby suppressing the conduction to the via conductor 14. When heat and current are applied to the wiring conductor 15 and the via conductor 14 and used for a long period of time, the disconnection at the connection portion between the wiring conductor 15 and the via conductor 14 can be effectively suppressed.

[0049] In addition, the thermal conductivity of the surface electrode 13 may be made greater than the thermal conductivity of the via conductor 14. As described above, while heat conduction to the via conductor 14 side is suppressed, heat conduction through the surface electrode 13 side on the recess 12 side becomes easy, and when heat and current are applied to the wiring conductor 15, the surface electrode 13, and the via conductor 14, and when used for a long period of time, cracks between the surface electrode 13 and the via conductor 14 can be effectively suppressed. For example, the surface electrode 13 and the via conductor 14 may be made of a metal conductor containing copper or a mixed metal conductor of copper and tungsten or molybdenum, and the via conductor 14 may be made of a metal conductor containing tungsten or molybdenum, so that the thermal conductivity of the surface electrode 13 is greater than that of the via conductor 14. In addition, the content of glass powder and ceramic powder contained in the surface electrode 13 may be smaller than the content of glass powder and ceramic powder contained in the via conductor 14, so that the thermal conductivity of the surface electrode 13 is greater than that of the via conductor 14.

[0050] The electronic device can be a small-sized, high-functional, and excellent long-term reliability electronic device by including the electronic component 2 in the mounting portion 11 a of the wiring substrate 1 having the above-described structure.

[0051] The electronic module includes a module substrate and the electronic device having the above structure connected to the module substrate, so that the electronic module can be provided with excellent long-term reliability.

[0052] (Second embodiment)

[0053] Next, refer to Figures 4 to 6 , while explaining the wiring substrate 1 based on the second embodiment.

[0054] The wiring substrate 1 of the second embodiment is different from the wiring substrate 1 of the above-mentioned embodiment in that, in a perspective plan view, the via-hole conductor 14 is arranged along the outer edge of the first region 15a, and the heat dissipation portion 17 is a heat dissipation conductor group 17G. In addition, when the heat dissipation portion 17 is the heat dissipation conductor group 17G, the central portion of the region including the plurality of heat dissipation conductors constituting the heat dissipation conductor group 17G can be considered as the central portion of the heat dissipation conductor group 17G, that is, the central portion of the heat dissipation portion 17.

[0055] The surface electrode 13 is Figure 4 as well as Figure 5 In the example shown, the via conductor 14 is shown by hatching. Figure 4 as well as Figure 5 In the example shown, the area where the side surface of the via conductor 14 overlaps with the wiring conductor 15 is indicated by a dotted line. Figure 4 as well as Figure 5 In the example shown, this is indicated by shading.

[0056] The heat dissipation portion 17, which is a heat dissipation conductor group 17G, is formed in the same manner as the metal body of the first embodiment. After a plurality of holes are set in the ceramic green sheet for the insulating substrate 11 by stamping or laser processing using a mold or punching, metal paste for the heat dissipation conductors is arranged in each of the plurality of holes, thereby being manufactured.

[0057] According to the wiring substrate 1 of the second embodiment, as with the wiring substrate 1 of the above-mentioned embodiment, it is possible to suppress the heat of the electronic component 2 that is conducted through the wiring conductor 15 from being conducted to the via conductor 14, and it becomes easy to conduct heat through the heat dissipation portion 17. When heat and current are applied to the wiring conductor 15 and the via conductor 14 and they are used for a long period of time, it is possible to suppress the wire from being broken at the connection portion between the wiring conductor 15 and the via conductor 14.

[0058] Furthermore, if the via-hole conductors 14 are arranged along the outer edge of the first region 15a, heat conduction to the sides of the respective via-hole conductors 14 can be dispersed, and heat conduction to the sides of the via-hole conductors 14 can be easily dispersed along the outer edge of the first region 15a and through the wiring conductors 15, and when used for a long period of time, disconnection at the connection between the wiring conductors 15 and the via-hole conductors 14 can be suppressed.

[0059] Furthermore, when viewed from above, if the via-hole conductors 14 are located on the sides of the corners forming the insulating substrate 11, heat conduction from the wiring conductors 15 to the via-hole conductors 14 can be dispersed, and disconnection at the connection between the wiring conductors 15 and the via-hole conductors 14 can be suppressed during long-term use.

[0060] In addition, Figures 4 to 6 In the example shown, two via-hole conductors 14 are arranged along the outer edge of the first region 15a. Three or more via-hole conductors 14 may be arranged along the outer edge of the first region 15a.

[0061] Furthermore, when a plurality of via-hole conductors 14 are arranged along the outer edge of the first region 15a, as shown in FIG. Figures 4 to 6 As in the example shown, the number of via-hole conductors 14 , wiring conductors 15 , and via-hole conductors 14 disposed on the opposite side of the heat dissipation portion 17 in the first region 15 a may be equal.

[0062] Furthermore, the wiring substrate 1 has a cavity 16 on the upper surface for accommodating the electronic component 2. In the above, the first region 15a of the wiring conductor 15 is as shown in FIG. Figures 4 to 6As in the example shown, a portion of the first region 15a may be located further inside than the inner surface of the cavity 16 in a plan view and exposed. As described above, a portion of the first region 15a of the wiring conductor 15 is exposed, the lamination of the upper surface side and the lower surface side of the insulating substrate 11 at the corner of the cavity 16 is made good, and the heat conduction to the side wall side of the cavity 16 around the first region 15 is made good, thereby suppressing the heat conduction to the via conductor 14 side, thereby suppressing the disconnection at the connection portion of the wiring conductor 15 and the via conductor 14 when used for a long period of time.

[0063] The wiring board 1 of the second embodiment can be manufactured using the same manufacturing method as the wiring board 1 of the above-described embodiment except for the above-described aspects.

[0064] (Third embodiment)

[0065] Next, refer to Figure 7 to Figure 9 , while explaining the wiring substrate 1 according to the third embodiment.

[0066] In the wiring substrate 1 of the third embodiment, the difference from the wiring substrate 1 of the above-mentioned embodiment is that, when viewed from above, the via conductors 14 are respectively located on the four corners of the insulating substrate 11, and the wiring conductor 15 has a first area 15a of the wiring conductor 15 that surrounds the area located between the mounting portion 11a and the via conductor 14.

[0067] The surface electrode 13 is Figure 7 as well as Figure 8 In the example shown, the via conductor 14 is shown by shading. Figure 7 as well as Figure 8 In the example shown, the area where the side surface of the via conductor 14 overlaps with the wiring conductor 15 is indicated by a dotted line. Figure 7 as well as Figure 8 In the example shown, this is indicated by shading.

[0068] According to the wiring substrate 1 of the third embodiment, as with the wiring substrate 1 of the above-mentioned embodiment, it is possible to suppress the heat of the electronic component 2 that conducts heat through the wiring conductor 15 from being conducted to the via conductor 14, and it becomes easy to conduct heat through the heat dissipation portion 17. When heat and current are applied to the wiring conductor 15 and the via conductor 14 and they are used for a long period of time, it is possible to suppress the wire from being broken at the connection portion between the wiring conductor 15 and the via conductor 14.

[0069] Furthermore, if the via-hole conductors 14 and the first regions 15a of the wiring conductors 15 are located at the four corners of the wiring substrate 1, it becomes easy to diffuse and conduct heat in different directions of the four via-hole conductors 14, and while suppressing heat conduction to the sides of the individual via-hole conductors 14, heat and current are applied to the wiring conductors 15, the surface electrodes 13, and the via-hole conductors 14, and when used for a long period of time, disconnection at the connection between the wiring conductors 15 and the via-hole conductors 14 can be suppressed.

[0070] In addition, in the case where some symbols are omitted, Figure 8 In the example shown, if the first regions 15a of the via-hole conductor 14 and the wiring conductor 15 are located at the four corners of the wiring substrate 1 when viewed from above, and the first regions 15a are smaller than the heat dissipation portion 17 (W2<W1) in a direction perpendicular to an imaginary straight line M connecting the central portion of the via-hole conductor 14 and the central portion of the heat dissipation portion 17, it is easier to arrange the first regions 15a on the via-hole conductor 14 side, thereby effectively suppressing the heat of the electronic component 2 that is conducted through the wiring conductor 15 from being conducted to the via-hole conductor 14, making it easier to conduct heat through the heat dissipation portion 17, and effectively suppressing disconnection at the connection portion between the wiring conductor 15 and the via-hole conductor 14 when heat and current are applied to the wiring conductor 15 and the via-hole conductor 14 and they are used for a long period of time.

[0071] The wiring board 1 of the third embodiment can be manufactured using the same manufacturing method as the wiring board 1 of the above-described embodiment except for the above-described aspects.

[0072] (Fourth embodiment)

[0073] Next, refer to Figure 10 to Figure 12 , while explaining the wiring substrate 1 based on the fourth embodiment.

[0074] The wiring substrate 1 of the fourth embodiment is different from the wiring substrate 1 of the above-mentioned embodiment in that the first side has a recess 12 among the first and second sides constituting the corner of the insulating substrate 11, and the via conductor 14 is located closer to the first side than the second side.

[0075] The surface electrode 13 is Fig.10 as well as Fig.11 In the example shown, the via conductor 14 is shown by shading. Fig.10 as well as Fig.11 In the example shown, the area where the side surface of the via conductor 14 overlaps with the wiring conductor 15 is indicated by a dotted line. Fig.10 as well as Fig.11 In the example shown, this is indicated by shading.

[0076] According to the wiring substrate 1 of the fourth embodiment, as with the wiring substrate 1 of the above-mentioned embodiment, it is possible to suppress the heat of the electronic component 2 that is conducted through the wiring conductor 15 from being conducted to the via conductor 14, and it becomes easy to conduct heat through the heat dissipation portion 17. When heat and current are applied to the wiring conductor 15 and the via conductor 14 and they are used for a long period of time, it is possible to suppress the wire from being broken at the connection portion between the wiring conductor 15 and the via conductor 14.

[0077] Regarding the via-hole conductor 14, the first side of the first side and the second side constituting the corner of the insulating substrate 11 has the recess 12, and the via-hole conductor 14 is located closer to the first side than the second side. Fig.11 As shown in the example, the via-hole conductor 14 is located near the surface electrode 13 with respect to the imaginary straight lines N1 and N2 connecting the corners of the mounting portion and the insulating substrate 11. Since the via-hole conductor 14 is located near the surface electrode 13, the heat of the electronic component 2 conducted through the wiring conductor 15 is also easily conducted to the surface electrode 13 side, and the conduction to the via-hole conductor 14 can be further suppressed. When heat and current are applied to the wiring conductor 15 and the via-hole conductor 14 and used for a long period of time, the disconnection at the connection portion of the wiring conductor 15 and the via-hole conductor 14 can be effectively suppressed.

[0078] If the volume of the via-hole conductor 14 between the wiring conductor 15 on the first surface side and the wiring conductor 15 on the third surface side is smaller than the volume of the surface electrode 13 between the wiring conductor 15 on the first surface side and the wiring conductor 15 on the third surface side, the current applied to the via-hole conductor 14 becomes smaller, and when used for a long period of time, the wire breakage at the connection portion between the wiring conductor 15 and the via-hole conductor 14 can be suppressed.

[0079] Furthermore, if the via-hole conductors 14 and the first regions 15a of the wiring conductors 15 are located at the four corners of the wiring substrate 1, it becomes easy to diffuse and conduct in different directions of the four via-hole conductors 14, and while suppressing heat conduction to the via-hole conductor 14 side, when heat and current are applied to the wiring conductors 15, the surface electrodes 13, and the via-hole conductors 14, and when used for a long period of time, it is possible to suppress disconnection at the connection between the wiring conductors 15 and the via-hole conductors 14.

[0080] The wiring board 1 of the fourth embodiment can be manufactured using the same manufacturing method as the wiring board 1 of the above-described embodiment except for the above-described aspects.

[0081] The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, the insulating substrate 11 may be rectangular with notches or chamfers on the side surfaces or corners in a plan view.

[0082] In the wiring substrate 1 of the second embodiment to the wiring substrate 1 of the fourth embodiment, the inner surface of the cavity 16 is formed perpendicularly relative to the upper surface of the insulating substrate 11 when viewed in longitudinal section, but the inner surface of the cavity 16 can also be inclined so that the opening side of the cavity 16 is wider than the bottom side of the cavity 16.

[0083] In addition, the structures of other embodiments may be combined in the wiring substrates 1 of the first to fourth embodiments. For example, in the wiring substrate 1 of the first embodiment, the via conductors 14 and the first regions 15a of the wiring conductors 15 may be located at the four corners of the wiring substrate 1, similarly to the wiring substrate 1 of the third embodiment.

[0084] In addition, in the wiring substrate 1 of the fourth embodiment, the heat dissipation conductor group 17G can also be used for the wiring substrate 1 having one heat dissipation portion 17 similarly to the wiring substrate 1 of the first embodiment.

[0085] In addition, in the wiring substrate 1 of the first embodiment, the cavity 16 may be provided similarly to the wiring substrate 1 of the second embodiment and the wiring substrate 1 of the third embodiment.

[0086] In addition, the wiring substrate 1 can also be manufactured by mass-producing substrates.

Claims

1. A wiring substrate, comprising: An insulating substrate having a first surface which is in a square shape when viewed from above, and having a mounting portion for an electronic component on the first surface; The first via-hole conductor and the second via-hole conductor are located in the insulating substrate and are located at corners when viewed from above, and extend along the thickness direction of the insulating substrate; a first wiring conductor and a second wiring conductor located on the first surface, the first wiring conductor connecting the mounting portion and the first via-hole conductor, and the second wiring conductor connecting the mounting portion and the second via-hole conductor; and The heat dissipation portion is located in the insulating substrate and is located at a position overlapping with the mounting portion when viewed from above. The first surface has a first region surrounded by the first wiring conductor in a plan view between the heat dissipation portion and the first via conductor in a plan view, and the insulating substrate is exposed in the first region. The first surface has a second region surrounded by the second wiring conductor in a plan view between the heat dissipation portion and the second via conductor in a plan view, and the insulating substrate is exposed in the second region. The insulating substrate has a first recess and a second recess on a second surface connected to the first surface, and the second surface where the first recess is located and the second surface where the second recess is located face each other with the heat dissipation portion interposed therebetween. The first recess has a first surface electrode, the second recess has a second surface electrode, the first wiring conductor is connected to the first surface electrode in addition to the mounting portion and the first via conductor, The second wiring conductor is connected to the second surface electrode in addition to the mounting portion and the second via conductor, and the second via conductor, the second wiring conductor, and the second region are located on opposite sides of the heat dissipation portion from the first via conductor, the first wiring conductor, and the first region in a perspective plan view. In a perspective plan view, the first region is closer to the first via conductor than the heat dissipation portion. The second region is located closer to the second via-conductor side than the heat dissipation portion in a plan perspective view.

2. The wiring substrate according to claim 1, wherein: The first side of the first side and the second side constituting the corner of the insulating substrate has the first recess and the second recess, The first via-hole conductor and the second via-hole conductor are located closer to the first side than to the second side.

3. The wiring substrate according to claim 1 or 2, wherein: The first via-hole conductor and the second via-hole conductor located at a corner of the insulating substrate are arranged along a direction orthogonal to a diagonal line of the insulating substrate in a plan view.

4. A wiring substrate, comprising: An insulating substrate having a first surface which is in a square shape when viewed from above, and having a mounting portion for an electronic component on the first surface; The first via-hole conductor and the second via-hole conductor are located in the insulating substrate and are located at corners when viewed from above, and extend along the thickness direction of the insulating substrate; a first wiring conductor and a second wiring conductor located on the first surface, the first wiring conductor connecting the mounting portion and the first via-hole conductor, and the second wiring conductor connecting the mounting portion and the second via-hole conductor; and The heat dissipation portion is located in the insulating substrate and is located at a position overlapping with the mounting portion when viewed from above. The first surface has a first region surrounded by the first wiring conductor in a plan view between the heat dissipation portion and the first via conductor in a plan view, and the insulating substrate is exposed in the first region. The first surface has a second region surrounded by the second wiring conductor in a plan view between the heat dissipation portion and the second via conductor in a plan view, and the insulating substrate is exposed in the second region. The insulating substrate has a first recess and a second recess on a second surface connected to the first surface, and the second surface where the first recess is located and the second surface where the second recess is located face each other with the heat dissipation portion interposed therebetween. The first recess has a first surface electrode, and the second recess has a second surface electrode. The first side of the first side and the second side constituting the corner of the insulating substrate has the first recess and the second recess, The first via-hole conductor and the second via-hole conductor are located closer to the first side than to the second side. In a perspective plan view, the second via-hole conductor, the second wiring conductor, and the second region are located on opposite sides of the heat dissipation portion from the first via-hole conductor, the first wiring conductor, and the first region. In a perspective plan view, the first region is closer to the first via conductor than the heat dissipation portion. The second region is located closer to the second via-conductor side than the heat dissipation portion in a plan perspective view.

5. The wiring substrate according to claim 4, wherein: The first via-hole conductor and the second via-hole conductor located at a corner of the insulating substrate are arranged along a direction orthogonal to a diagonal line of the insulating substrate in a plan view.

6. An electronic device, The mounting portion of the wiring substrate according to any one of claims 1 to 5 has an electronic component.

7. An electronic module comprising: a base plate for a module; and The electronic device according to claim 6 is connected to the module substrate.

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