Wiring board, electronic device, and electronic module

Abstract

A wiring board according to the present invention comprises: an insulating board having a first surface and a second surface; a first external electrode and a third external electrode positioned at opposing corners of the first surface along a first diagonal line; a second external electrode and a fourth external electrode positioned at opposing corners along a second diagonal line; a first connection electrode, at least a portion of which overlaps the first external electrode, and which is connected to the first external electrode through a first through-conductor extending from the first surface toward the bottom surface of a recess; and a second connection electrode, at least a portion of which overlaps the third external electrode, and which is connected to the third external electrode through a second through-conductor extending from the first surface toward the bottom surface of a recess.

Description

[Technical Field]

[0001] The present disclosure relates to a wiring board for mounting electronic components, an electronic device, and an electronic module. [Background technology]

[0002] 2. Description of the Related Art Various types of package-type wiring boards that can be surface-mounted on a mounting board together with electronic circuit components have been proposed as package-type wiring boards that are used to be connected to an external device.

[0003] Patent document 1 discloses a wiring board having an external electrode located on a first surface of a rectangular insulating substrate and a connection electrode located on a second surface of the insulating substrate on which an electronic component that is rectangular in plan view is mounted.

[0004] The connection electrodes include first and second connection electrodes located along one side of the electronic component. The external electrodes include first to fourth external electrodes located at the four corners of the insulating substrate. Inside the insulating substrate, there are located diagonal wiring that electrically connects the second and fourth external electrodes located on a diagonal line of the first surface in a plan view and includes a portion that is inclined with respect to the second surface, and embedded wiring that extends from the second connection electrode corresponding to the second external electrode in a plan view toward the third external electrode. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2019 / 146699 Brochure Summary of the Invention

[0006] A wiring board according to one embodiment of the present disclosure includes an insulating substrate that is rectangular in plan view and has a first surface, a second surface opposite to the first surface, and a recess that opens into the second surface; external electrodes located on the first surface; and connection electrodes located on a bottom surface of the recess, the external electrodes including a first external electrode and a third external electrode located at corners that face each other along a first diagonal line of the first surface and that are electrically connected to the connection electrodes; and a second external electrode and a fourth external electrode located at corners that face each other along a second diagonal line of the first surface, the second external electrode and the fourth external electrode being located inside the insulating substrate and inclined relative to the first surface. The device is further provided with a first through conductor that is connected by a connection wiring including a diagonal portion, and that overlaps at least a portion of the first external electrode in a planar perspective and extends from the first surface toward the bottom surface, and a second through conductor that overlaps at least a portion of the third external electrode in a planar perspective and extends from the first surface toward the bottom surface, and the connection electrodes include a first connection electrode that is connected to the first external electrode via the first through conductor and a second connection electrode that is connected to the third external electrode via the second through conductor, and the first connection electrode and the second connection electrode are located at positions along the first diagonal line in a planar perspective.

[0007] An electronic device according to an aspect of the present disclosure includes a wiring board according to an aspect of the present disclosure and an electronic component connected to the wiring board.

[0008] An electronic module according to one aspect of the present disclosure includes an electronic device according to one aspect of the present disclosure and a module substrate connected to the electronic device. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is an overall perspective view of an electronic device according to a first embodiment, with a cover removed. [Figure 2] FIG. 2 is a perspective view of the wiring board of the electronic device as viewed from the bottom side. [Figure 3] FIG. 2 is a plan view of a wiring board provided in the electronic device. [Figure 4] FIG. 2 is a perspective view of the configuration of the lower surface of the wiring board as seen from above. [Figure 5] 2 is a perspective view showing the configuration of the upper surface and the configuration of the lower surface of the wiring board superimposed on each other. FIG. [Figure 6] 6 is a cross-sectional view of the wiring board shown in FIG. 3 taken along line VI-VI. [Figure 7] 7 is a cross-sectional view of the wiring board shown in FIGS. 3 and 4 taken along line VII-VII. FIG. [Figure 8] 8 is a cross-sectional view of the wiring board shown in FIG. 4 taken along line VIII-VIII. [Figure 9] FIG. 10 is a plan view of a wiring board according to a second embodiment. [Figure 10] 10 is a cross-sectional view of the wiring board shown in FIG. 9 taken along the line XX. [Figure 11] FIG. 10 is a plan view of a wiring board according to a third embodiment. [Figure 12] 12 is a cross-sectional view of the wiring board shown in FIG. 11 taken along line XII-XII. [Figure 13] FIG. 10 is a cross-sectional view of a wiring board according to a fourth embodiment. [Figure 14] 10 is a perspective view showing the configuration of the upper surface and the configuration of the lower surface of the wiring board according to the fifth embodiment superimposed on each other. FIG. [Figure 15] 13 is a perspective view showing the configuration of the upper surface and the configuration of the lower surface of the wiring board according to the sixth embodiment superimposed on each other. FIG. [Figure 16] FIG. 13 is a plan view of a wiring board according to a seventh embodiment. [Figure 17] FIG. 10 is a plan view of a modified example of the wiring board. [Figure 18] FIG. 10 is a plan view of another modified example of the wiring board. [Figure 19] FIG. 10 is a plan view of yet another modified example of the wiring board. DETAILED DESCRIPTION OF THE INVENTION

[0010] [Embodiment 1] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. A wiring board having a configuration that can ensure insulation between internal wirings even when the height is further reduced is desired. According to one aspect of the present disclosure, insulation between internal wirings can be ensured even when the height is further reduced.

[0011] The distinction between top and bottom in the following description is for convenience and does not limit the top and bottom when the wiring board and electronic device are actually used. In this specification, the surface of insulating substrate 110 or wiring board 100 on which electronic component 150 is mounted is defined as the top surface. In the drawings, the positive direction of the Z axis is the upward direction. The X axis is the longitudinal direction of insulating substrate 110 or wiring board 100, and the Y axis is an axis perpendicular to the X axis and Z axis.

[0012] Fig. 1 is an overall perspective view of an electronic device 10 of this embodiment with the lid 120 removed. Fig. 1 is a view of the top surface to which the lid 120 is joined. Fig. 2 is a perspective view of the wiring board 100 of the electronic device 10 as seen from the bottom surface opposite to the side to which the lid 120 is joined.

[0013] The electronic device 10 includes a wiring board 100, an electronic component 150, and a cover 120. The wiring board 100 includes an insulating substrate 110, electrodes (connection electrodes 113 and external electrodes 114), wiring, and the like.

[0014] The insulating substrate 110 has a first surface S1 located on the side opposite to the side to which the lid 120 is bonded, a second surface S2 located on the side opposite to the first surface S1, and a recess 111 which is a recessed area opening to the second surface S2. The insulating substrate 110 has a flat base 110b and a frame 110a located on the upper surface of the base 110b.

[0015] An electronic component 150 is positioned inside the recess 111. The frame 110a defines the open surface of the recess 111, a bottom surface 7 (a surface on which the electronic component 150 is placed) opposite the open surface, and side surfaces of the recess 111. The side surfaces of the recess 111 are each parallel to the z direction. In this specification, the term "parallel" is intended to mean that they do not intersect with a reference plane or reference line at a visually recognizable level, and does not require strict parallelism.

[0016] A frame-shaped metallization layer 112 is located on the upper surface of the frame 110a, i.e., on the bonding surface between the frame 110a and the lid 120. The frame-shaped metallization layer 112 is bonded to the lid 120 using a sealing material such as a gold-tin alloy (AuSn) or silver solder. Although not particularly limited, the size of the wiring board 100 here is approximately 0.8 to 10.0 mm on a side in the xy plane, and approximately 0.1 to 2.0 mm thick in the z direction. The wiring board 100 according to this embodiment is particularly useful when the thickness of the wiring board 100 is 0.2 mm or less and the thickness of the base 110b is 0.1 mm or less, making it difficult to ensure insulation.

[0017] A first connection electrode 1131 and a second connection electrode 1132 are located on the bottom surface 7 of the recess 111. The first connection electrode 1131 and the second connection electrode 1132 may be collectively referred to as connection electrodes 113. By attaching an electronic component 150 to the connection electrode 113, that is, by connecting the electronic component 150 to the wiring board 100, an electronic device 10 including the wiring board 100 and the electronic component 150 is formed.

[0018] The electronic component 150 and the connection electrode 113 are connected via a bonding material 160 serving as a conductive adhesive. The bonding material 160 may be, for example, a resin to which conductive particles such as silver have been added. If the bonding material 160 is thermosetting, the bonding material 160 is applied to the connection electrode 113 in advance, and the electronic component 150 is positioned relative to the connection electrode 113 (bonding material 160) and heated, thereby connecting the electronic component 150 to the connection electrode 113 via the bonding material 160. The connection electrode 113 may have a convex shape relative to the bottom surface 7 of the recess 111. This allows the electronic component 150 to be fixed within the recess 111 at a distance from the bottom surface 7. If the electronic component 150 generates vibrations during operation, the thicknesses of the connection electrode 113 and the bonding material 160 may be determined so that the electronic component 150 does not come into contact with the bottom surface and the lid 120 within the recess 111 during vibration.

[0019] The connection electrodes 113 may be embedded in the bottom surface 7 of the recess 111, with the upper surfaces of the connection electrodes 113 being flush with the bottom surface 7. This allows the wiring substrate 100 to be made even lower in height. In this case, a bonding material is located on the upper surfaces of the connection electrodes 113, and the electronic component 150 is located on this bonding material. This allows the electronic component 150 to be fixed in the recess 111 at a distance from the bottom surface 7.

[0020] A first external electrode 1141, a second external electrode 1142, a third external electrode 1143, and a fourth external electrode 1144 are located at the four corners of the first surface S1 opposite the recess 111 of the base 110b. The first external electrode 1141, the second external electrode 1142, the third external electrode 1143, and the fourth external electrode 1144 may be collectively referred to as external electrodes 114. The external electrodes 114 are joined to the module substrate 200. Of the external electrodes 114, the first external electrode 1141 and the third external electrode 1143 are electrodes to which a potential corresponding to the supply voltage to the electronic component 150 is applied, and the second external electrode 1142 and the fourth external electrode 1144 are electrodes that are grounded.

[0021] The electronic device 10 is included in an electronic module 1 together with a module substrate 200 to which external electrodes 114 are joined using solder 210 (see FIGS. 6 and 7). Examples of the electronic component 150 include a piezoelectric vibration element and a quartz crystal unit used in oscillators, vibrators, etc. Furthermore, multiple electronic components 150 may be located in one recess 111 as needed.

[0022] The insulating substrate 110 is made of a ceramic material, such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, or a glass-ceramic sintered body. Here, the insulating substrate 110 will be described as being an aluminum oxide sintered body (alumina sintered body). The frame portion 110a and the base portion 110b of the insulating substrate 110 have an integral structure.

[0023] The lid 120 is made of a conductive metal and is joined to the frame-shaped metallization layer 112 to hermetically seal the recess 111. A conductive sealing material (sealant) such as AuSn or silver solder is used for sealing. The lid 120 may be grounded. Grounding the lid 120 reduces the propagation of external noise into the recess 111. The lid 120 is connected to the frame-shaped metallization layer 112 via the conductive sealing material. As shown in FIG. 8 , the frame-shaped metallization layer 112 is connected to a second external electrode 1142 of the wiring board 100 via an inner-frame wiring 116 and a via conductor 1153. The inner-frame wiring 116 and the via conductor 1153 will be described later. Grounding the second external electrode 1142 puts the lid 120 in a grounded state.

[0024] The frame-shaped metallization layer 112 is made of a conductive metal and is printed on the bonding surface of the frame portion 110a. The frame-shaped metallization layer 112, the exposed surfaces of the connection electrodes 113, and the exposed surfaces of the external electrodes 114 may be covered with a plating layer of nickel and / or gold. For example, the exposed surfaces may be nickel-plated to a thickness of 1 to 20 μm, and then a gold-plated layer to a thickness of 0.1 to 3.0 μm may be formed on this nickel-plated layer. This reduces the possibility of oxidation corrosion of the surface and also facilitates and strengthens the connection between the frame-shaped metallization layer 112 located on the upper surface of the insulating substrate 110, which is an insulator, and the lid 120, which is a metal conductor.

[0025] Next, the electrical wiring in the wiring board 100 will be described.

[0026] FIG. 3 is a plan view of wiring board 100. FIG. 4 is a perspective view of the configuration of first surface S1 of wiring board 100 as seen from the second surface S2 side. FIG. 5 is a perspective view of the configuration of second surface S2 of wiring board 100 superimposed on the configuration of first surface S1. FIG. 6 is a cross-sectional view of wiring board 100 shown in FIG. 3, taken along line VI-VI. FIG. 7 is a cross-sectional view of wiring board 100 shown in FIGS. 3 and 4, taken along line VII-VII. FIG. 8 is a cross-sectional view of wiring board 100 shown in FIG. 4, taken along line VIII-VIII. FIGS. 6 and 7 show the entire electronic module 1, including electronic component 150 connected to connection electrode 113, lid 120 bonded to frame-shaped metallized layer 112, and module substrate 200 connected to external electrode 114 via solder 210 (as electronic module 1, electronic device 10 is attached to module substrate 200).

[0027] 6, the first connection electrode 1131 located on the bottom surface 7 of the recess 111 is connected to the first external electrode 1141 directly below by a first through conductor 1151 that vertically penetrates the insulating substrate 110 (base 110b). The second connection electrode 1132 is connected to the third external electrode 1143 directly below by a second through conductor 1152 that vertically penetrates the insulating substrate 110 (base 110b).

[0028] A convex floating island portion 2 may be located on the bottom surface of the recess 111. The first connection electrode 1131 may be located on the floating island portion 2. The floating island portion 2 may be made of the same material as the insulating substrate 110, and may be integral with the insulating substrate 110. The thickness (length in the Z direction) of the floating island portion 2 may be adjusted as appropriate depending on the characteristics, shape, etc. of the electronic component 150 to be mounted.

[0029] 8, the frame-shaped metallized layer 112 is connected to the second external electrode 1142 through the in-frame wiring 116 located inside the frame portion 110a and the base portion 110b and the via conductor 1153. The second external electrode 1142 and the fourth external electrode 1144 are connected to the wiring board 100. Second diagonal DL2 The first and third external electrodes 1141 and 1143 are electrically connected to the electronic component 150 and are connected to each other by a connecting wire 117 (wire provided inside the insulating substrate 110) located inside the base 110b. The connecting wire 117 is necessary for electrical continuity when the exposed surfaces of the second external electrode 1142 and the fourth external electrode 1144 are covered with a plating layer. On the other hand, the first external electrode 1141 and the third external electrode 1143, which are electrically connected to the electronic component 150, are also connected to the wiring board 100. 1st diagonal DL1 It is located above.

[0030] The connection electrode and the ground electrode are 1st diagonal DL1, the second diagonal DL2 By placing the electronic device 10 on top, even if the electronic device 10 is mistakenly mounted on the module substrate 200 in a position rotated 180 degrees, the possibility of the module substrate 200 malfunctioning due to the polarity of the electronic device 10 can be reduced.

[0031] 6 and 7, the first connection electrode 1131 is connected to the first external electrode 1141 by a first through conductor 1151. A coating layer 110f made of the same material as the insulating substrate 110 (base portion 110b), that is, aluminum oxide ceramic paste in this case, is provided on the first surface S1 of the insulating substrate 110. This coating layer 110f allows the ends of the first external electrode 1141 and the fourth external electrode 1144 to penetrate into the insulating substrate 110.

[0032] 8 is a cross-sectional view of the wiring board 100 taken along the cross-sectional line VIII-VIII, including the second external electrode 1142, the fourth external electrode 1144, and the connection wiring 117. The first end of the in-frame wiring 116 contacts the side of the frame-shaped metallization layer 112 opposite to the bonding surface with the lid 120, and is covered by a coating layer 110e provided facing the recess 111, so is not exposed to the outside. The in-frame wiring 116 contacts the upper end of the via conductor 1153 near a second end opposite to the first end. The lower end of the via conductor 1153 contacts the second external electrode 1142. The material of the coating layer 110e may be the same as that of the coating layer 110f.

[0033] The connection wiring 117 connecting the second external electrode 1142 and the fourth external electrode 1144 has both ends in contact with the second external electrode 1142 and the fourth external electrode 1144, respectively, and electrically connects the second external electrode 1142 and the fourth external electrode 1144. The portion of the connection wiring 117 other than both ends is embedded inside the insulating substrate 110 by the above-mentioned coating layer 110f.

[0034] The connection wiring 117 includes a portion whose extension direction (i.e., the direction connecting the second external electrode 1142 and the fourth external electrode 1144) is inclined obliquely with respect to the first surface S1 of the insulating substrate 110. That is, the distance of the connection wiring 117 from the lower surface of the insulating substrate 110 (the thickness of the coating layer 110f) varies along the extension direction of the connection wiring 117. The thickness of the coating layer 110f increases toward the center. As a result, the connection wiring 117 extends obliquely from both ends of the lower surface of the insulating substrate 110 into the interior of the insulating substrate 110. The inclination angle of the connection wiring 117 with respect to the lower surface of the insulating substrate 110 and the length of the inclined portion may be determined appropriately depending on the length of the wiring and / or its positional relationship with other wiring. Furthermore, the inclination angle does not need to be constant (i.e., the connection wiring 117 does not need to be linear in cross section); here, the connection wiring 117 has a curved shape in cross section.

[0035] Thus, wiring board 100 includes insulating substrate 110 that is rectangular in plan view and has first surface S1, second surface S2 located on the opposite side to first surface S1, and recess 111 that opens into second surface S2. Wiring board 100 also includes external electrode 114 located on first surface S1 and connection electrode 113 located on the bottom surface of recess 111.

[0036] The external electrode 114 is disposed along the first diagonal of the first surface S1. DL1 The first surface S1 includes a first external electrode 1141 and a third external electrode 1143 located at opposite corners along the second diagonal line of the first surface S1 and electrically connected to the connection electrode 113. DL2 The outer electrodes 114 include a second outer electrode 1142 and a fourth outer electrode 1144 located at opposite corners along the axis.

[0037] The second external electrode 1142 and the fourth external electrode 1144 are located inside the insulating substrate 110 and are connected by a connection wiring 117 that includes a portion that is inclined relative to the first surface S1.

[0038] The wiring board 100 further includes a first penetrating conductor 1151 that at least partially overlaps with the first external electrode 1141 in a planar perspective and extends from the first surface S1 toward the bottom surface 7. The wiring board 100 further includes a second penetrating conductor 1152 that at least partially overlaps with the third external electrode 1143 in a planar perspective and extends from the first surface S1 toward the bottom surface 7.

[0039] The connection electrode 113 includes a first connection electrode 1131 connected to the first external electrode 1141 via a first through conductor 1151 and a second connection electrode 1132 connected to the third external electrode 1143 via a second through conductor 1152 .

[0040] The first connection electrode 1131 and the second connection electrode 1132 are arranged along a first diagonal line in a planar perspective view. DL1 It is located along the

[0041] According to the above configuration, in a planar perspective view, the first external electrode 1141 and the third external electrode 1143 are aligned along the first diagonal of the first surface S1. DL1 The second external electrode 1142 and the fourth external electrode 1144 are located at opposite corners along the second diagonal line of the first surface S1. DL2 The second external electrode 1142 and the fourth external electrode 1144 are located at corners facing each other along the first diagonal line in a planar perspective view. The second external electrode 1142 and the fourth external electrode 1144 are located inside the insulating substrate 110 and are connected by a connection wiring 117 that includes a portion that is inclined with respect to the first surface S1. The first connection electrode 1131 and the second connection electrode 1132 are located at corners facing each other along the first diagonal line in a planar perspective view. DL1 1. As a result, the wiring connecting the first connection electrode 1131 and the first external electrode 1141 and the wiring connecting the second connection electrode 1132 and the third external electrode 1143 do not overlap the connection wiring 117 in a planar perspective view. As a result, the height of the wiring board 100 can be reduced while ensuring insulation between the wiring for connecting the connection electrode 113 and the external electrode 114 and the ground connection wiring 117.

[0042] In addition, a first connection electrode 1131 and a second connection electrode 1132 for connecting the electronic component 150 are provided. 1st diagonal DL1 Since the electronic component 150 is positioned along the mounting surface 151, the posture of the electronic component 150 is likely to be stable when the electronic component 150 is mounted.

[0043] 3, the recess 111 has four inner walls 111a, 111b, 111c, and 111d. In a planar perspective, the first penetrating conductor 1151 may be located inside the first external electrode 1141 and offset from the center of the first connecting electrode 1131 in the opposite direction from inner wall 111a and / or inner wall 111d, which are closest to the first connecting electrode 1131. In addition, the second penetrating conductor 1152 may be located inside the second external electrode 1143 and offset from the center of the second connecting electrode 1132 in the opposite direction from inner wall 111b and / or inner wall 111c, which are closest to the second connecting electrode 1132.

[0044] In this case, a part of the first through conductor 1151 is connected to the first connection electrode 1131. A part of the first through conductor 1151 is exposed on the side surface of the island portion 2 and the bottom surface 7 of the recess 111.

[0045] According to the above configuration, the first through conductor 1151 is located away from the side wall of the recess 111, which is subjected to thermal stress when the wiring substrate 100 is sealed with the lid 120, thereby reducing the possibility of cracks originating from the first through conductor 1151 due to the thermal stress.

[0046] The first connection electrode 1151 may be offset at least in the direction opposite to the inner wall 111a from the center of the first connection electrode 1131. When the wiring substrate 100 is a rectangle that is longer in the X direction than in the Y direction in a plan view, as shown in FIG. 3 etc., thermal stress increases in the long side direction (X direction). Therefore, offsetting the first connection electrode 1151 in the direction opposite to the inner wall 111a from the center of the first connection electrode 1131 along the X direction is effective in reducing the possibility of the above-mentioned cracks occurring.

[0047] At least a portion of the first through conductor 1151 may be located outside the first connection electrode 1131 in a planar perspective view.

[0048] According to the above configuration, the possibility of cracks originating from first through conductors 1151 due to thermal stress when wiring substrate 100 is sealed with lid 120 can be further reduced.

[0049] A convex floating island portion 2 is located on the bottom surface of the recess 111, and the first connection electrode 1131 may be located on the floating island portion 2.

[0050] According to the above configuration, the first connection electrode 1131 is located on the convex island portion 2 at the bottom surface of the recess 111, so that the shape of the first connection electrode 1131 is easily maintained when the recess 111 of the insulating substrate 110 is formed.

[0051] Next, an example of a method for manufacturing the wiring substrate 100 will be described.

[0052] First, through holes are formed in a ceramic green sheet that will become insulating substrate 110 and a conductor is injected into the through holes, thereby forming first through conductors 1151, second through conductors 1152, and via conductors 1153.

[0053] Then, a metallization paste is applied using a mask to the upper surface of the ceramic green sheet in a positional range appropriate for forming the connection electrodes 113 and the in-frame wiring 116. Next, a ceramic paste made of the same material as the ceramic green sheet is applied using a mask to a positional range appropriate for covering the portion of the metallization paste corresponding to the in-frame wiring 116. The application of the metallization paste and the ceramic paste is carried out by, for example, screen printing.

[0054] Thereafter, metallization paste is applied to the lower surface of the ceramic green sheet at each position of the external electrodes 114 using a mask. The second external electrode 1142 and the fourth external electrode 1144 are connected by the metallization paste applied at the position of the connection wiring 117 when viewed from the bottom. Ceramic paste is further applied using a mask from the gaps in the external electrodes 114 (including the areas where the metallization paste is applied) to near the inner boundaries of the external electrodes 114. At this time, the amount of ceramic paste applied may be increased or decreased, or may be non-uniform, depending on the inclination angle of the connection wiring 117, etc.

[0055] The ceramic green sheet coated with the metallization paste and ceramic paste on both sides is placed on a flat plate and pressed from above by a pressing jig having concaves and convexes corresponding to the recesses 111, the frame 110a, the floating island portions 2, and the connection electrodes 113. As a result, the recesses 111 are formed, and the metallization paste that will become the connection electrodes 113 is pressed downward toward the bottom surface 7 of the recesses 111, forming the floating island portions 2 and the connection electrodes 113 located on the bottom surface 7. Furthermore, the portion of the metallization paste that extends approximately parallel to the bottom surface 7 of the recesses 111 of the intra-frame wiring 116 is sandwiched and embedded between the coating layer 110e and the ceramic green sheet. The upper ends of the via conductors 1153 are pressed downward by the metallization paste and ceramic paste that will become the intra-frame wiring 116, so that they do not penetrate from the lower surface of the insulating substrate 110 to the bottom surface of the recesses 111.

[0056] Meanwhile, as the recess 111 is formed by the protrusion of the pressing jig, the ceramic green sheet, metallization paste, and ceramic paste are deformed in the area outside the recess 111 and filled into the recess of the pressing jig. As a result, the metallization paste that becomes the in-frame wiring 116 sandwiched between the coating layer 110e and the ceramic green sheet is embedded in the frame portion 110a.

[0057] Additionally, the metallization paste and ceramic paste are formed into a flat shape on the lower surface side of the ceramic green sheet, forming four external electrodes 114. The inner ends of the external electrodes 114 are pressed into the interior of the insulating substrate 110 by the ceramic paste. The metallization paste connecting the second external electrode 1142 and the fourth external electrode 1144 is pressed into the interior of the insulating substrate 110 by the ceramic paste, forming the connecting wiring 117.

[0058] In this way, the coating layers 110f and 110e are integrated with the ceramic green sheets. Then, a firing process is performed to obtain the wiring substrate 100, in which the metallization paste sandwiched between them becomes the frame-shaped metallization layer 112, the in-frame wiring 116, and the connection wiring 117, which are not exposed except at the bonding surfaces with the connection electrodes 113 and external electrodes 114. Thereafter, plating processes, firing processes, attachment of electronic components 150, bonding of the lid 120, etc. are performed as necessary.

[0059] When manufacturing wiring board 100 using the above manufacturing method, when forming recess 111, there is a possibility that the conductive material that will become first through conductor 1151 will flow toward the wall surface of recess 111. By designing the position of first through conductor 1151 after completion to be away from the side wall of recess 111, it is possible to reduce the possibility that the conductive material of first through conductor 1151 will deviate from the range where it can be connected to first connection electrode 1131.

[0060] [Embodiment 2] Other embodiments of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be used to designate components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0061] Fig. 9 is a plan view of a wiring board 100A according to embodiment 2. Fig. 10 is a cross-sectional view of the wiring board shown in Fig. 9 taken along line XX.

[0062] The wiring board 100A includes a first through conductor 1151A and a second through conductor 1152A.

[0063] A portion of the end face of the first through conductor 1151A on the bottom surface 7 side is connected to the first connection electrode 1131, and an insulating coating 3 may be located between the remaining portion of the end face of the first through conductor 1151A and the bottom surface 7 of the recess 111. For example, in a planar perspective view, the end face (upper end face) of the first through conductor 1151A that overlaps with the first connection electrode 1131 is connected to the lower surface of the first connection electrode 1131. On the other hand, the end face (upper end face) of the first through conductor 1151A that does not overlap with the first connection electrode 1131 abuts against the lower surface of the coating 3 that is located between the end face and the bottom surface 7 of the recess 111.

[0064] A portion of the end face (upper end face) of the second through conductor 1152A on the bottom surface 7 side is connected to the second connection electrode 1132, and an insulating coating portion 3 may be located between the remaining portion of the end face of the second through conductor 1152A and the bottom surface 7 of the recess 111.

[0065] According to this configuration, the first and second through conductors 1151A and 1152A are covered by the covering portion 3 and are not exposed at the bottom surface 7 of the recess 111. Therefore, the exposed surfaces of the first and second through conductors 1151A and 1152A at the bottom surface 7 of the recess 111 are not plated. This reduces the possibility that the first and second through conductors 1151A and 1152A will protrude from the bottom surface 7 of the recess 111. As a result, the possibility that the first and second through conductors 1151A and 1152A will come into contact with the electronic component 150 is reduced.

[0066] [Embodiment 3] Fig. 11 is a plan view of wiring board 100B according to embodiment 3. Fig. 12 is a cross-sectional view of wiring board 100B shown in Fig. 11 taken along line XII-XII.

[0067] The wiring board 100B includes a first through conductor 1151B and a second through conductor 1152B.

[0068] The wiring board 100B may include internal wiring 4 connected to an end face of the first through conductor 1151B on the bottom surface 7 side, at least a portion of which extends along a plane substantially parallel to the first surface S1, with the first through conductor 1151B located inside it in a planar perspective. The wiring board 100B may also include a covering portion 3 located between the internal wiring 4 and the bottom surface 7 of the recess 111 and adjacent to the first connection electrode 1131 in a planar perspective. The internal wiring 4 is wiring that connects the first through conductor 1151B and the first connection electrode 1131. In a planar perspective, the internal wiring 4 overlaps at least a portion of the first connection electrode 1131. In the example shown in FIG. 11, a portion of the first through conductor 1151B overlaps the first connection electrode 1131 in a planar perspective, but the first through conductor 1151B and the first connection electrode 1131 do not necessarily have to overlap.

[0069] According to this configuration, the internal wiring 4 is connected to the end of the first through conductor 1151B, thereby improving the connection reliability between the first connection electrode 1131 and the first through conductor 1151B. Furthermore, since the first through conductor 1151B is covered by the covering portion 3 and is not exposed at the bottom surface 7 of the recess 111, the exposed surface of the first through conductor 1151B at the bottom surface 7 of the recess 111 is not plated. This reduces the possibility that the first through conductor 1151B will protrude from the bottom surface 7 of the recess 111.

[0070] The wiring board 100B may include internal wiring 4 connected to an end face of the second penetrating conductor 1152B on the bottom surface 7 side, at least a portion of which extends along a plane substantially parallel to the first surface S1, with the second penetrating conductor 1152B located inside it in a planar perspective. The wiring board 100B may also include a covering 3 located between the internal wiring 4 and the bottom surface 7 of the recess 111 and adjacent to the first connection electrode 1131 in a planar perspective.

[0071] [Embodiment 4] FIG. 13 is a cross-sectional view of a wiring board 100C according to the fourth embodiment.

[0072] The wiring board 100C includes a first through conductor 1151C.

[0073] The wiring board 100C may include a first internal wiring 5 connected to an end face of the first through conductor 1151C on the bottom 7 side of the recess 111, at least a portion of which extends along a plane substantially parallel to the first surface S1, and the first through conductor 1151C is located inside the first internal wiring 5 in a planar perspective. The wiring board 100C may also include a covering portion 3C located between the first internal wiring 5 and the bottom 7 of the recess 111 and the first through conductor 1151C is located inside the first internal wiring 5 in a planar perspective, and a second internal wiring 6 connecting the first internal wiring 5 and the first connection electrode 1131. In the wiring board 100C, at least a portion of the covering portion 3C is located below the first connection electrode 1131. In a planar perspective of the wiring board 100C, the first through conductor 1151C is located inside the covering portion 3C. The first internal wiring 5 is a wiring that connects the second internal wiring 6 and the first through conductor 1151C. The shape of the second internal wiring 6 in plan view may be substantially the same as that of the first connection electrode 1131.

[0074] According to this configuration, the end face of the first through conductor 1151C is entirely covered with the covering portion 3C, so that the risk of the first through conductor 1151C protruding from the bottom surface 7 of the recess 111 is further reduced.

[0075] [Embodiment 5] FIG. 14 is a perspective view showing the configuration of the upper surface and the configuration of the lower surface of the wiring board 100D according to the fifth embodiment superimposed on each other.

[0076] The wiring board 100D includes a first connection electrode 1131D, a second connection electrode 1132D, a first through conductor 1151D, a second through conductor 1152D, and an internal wiring 4D.

[0077] The first connection electrode 1131D and the second connection electrode 1132D may be located at positions symmetrical with respect to the center of the second surface S2.

[0078] This configuration improves the degree of freedom when mounting electronic component 150 on wiring substrate 100D by moving first connection electrode 1131D and second connection electrode 1132D, which are positioned symmetrically about a point, in accordance with the shape / size of electronic component 150. Because first connection electrode 1131D and second connection electrode 1132D are positioned symmetrically about a point, if electronic component 150 also has a symmetrical shape, electronic component 150 can be stably mounted on first connection electrode 1131D and second connection electrode 1132D.

[0079] The connection wiring 117 may extend linearly in plan view from the second external electrode 1142 to the fourth external electrode 1144. This makes the configuration of the connection wiring 117 simple and compact.

[0080] The shape of the first connection electrode 1131D and the shape of the second connection electrode 1132D may be different in plan view.

[0081] If first connection electrode 1131D and second connection electrode 1132D have the same shape and are positioned point-symmetrically, it is difficult to determine the directionality of wiring substrate 100D. Therefore, first connection electrode 1131D and second connection electrode 1132D may be configured to have different shapes in a planar view. This allows either first connection electrode 1131D or second connection electrode 1132D to be used as an alignment mark, making it easier to determine the directionality of wiring substrate 100D.

[0082] Furthermore, even if the first connection electrode 1131D and the second connection electrode 1132D have the same shape, as shown in FIG. 14 , a portion of the internal wiring 4D connected to the second connection electrode 1132D may be exposed at the bottom surface 7 of the recess 111, and a portion of the internal wiring 4D may be plated in the same manner as the second connection electrode 1132D. The internal wiring 4D and the second connection electrode 1132D are connected inside the insulating substrate 110, and may be in contact with each other in a planar view, or may be separated from each other by a ceramic coating interposed therebetween. The internal wiring 4D connected to the first connection electrode 1131D is not exposed at the bottom surface 7 of the recess 111. The internal wiring 4D and the first connection electrode 1131D are connected inside the insulating substrate 110.

[0083] In this way, if a portion of the internal wiring 4D connected to the second connection electrode 1132D is exposed at the bottom surface 7 of the recess 111 and the internal wiring 4D connected to the first connection electrode 1131D is not exposed at the bottom surface 7 of the recess 111, the first connection electrode 1131D, the second connection electrode 1132D, and the exposed internal wiring 4D will no longer have a rotationally symmetrical shape with respect to the center of the second surface S2. In other words, when the first connection electrode 1131D is rotated 180 degrees around the center of the second surface S2 as the rotation axis, the first connection electrode 1131D will not overlap with the second connection electrode 1132D and the exposed internal wiring 4D.

[0084] This allows a part of the internal wiring 4D to be used as an alignment mark, making it easier to determine the directionality of the wiring board 100D.

[0085] The first through conductor 1151D may be located inside the first external electrode 1141 and offset from the center of the first connection electrode 1131D toward the inner wall of the recess 111 in a planar perspective. The second through conductor 1152D may be located inside the third external electrode 1143 and offset from the center of the second connection electrode 1132D toward the inner wall of the recess 111 in a planar perspective.

[0086] [Embodiment 6] FIG. 15 is a perspective view showing the configuration of the upper surface and the configuration of the lower surface of a wiring board 100E according to the sixth embodiment superimposed on each other.

[0087] The wiring board 100E includes a first connection electrode 1131E, a second connection electrode 1132E, a first through conductor 1151E, a second through conductor 1152E, and internal wiring 4E.

[0088] The first connection electrode 1131E and the second connection electrode 1132E may be located at positions symmetrical with respect to the center of the second surface S2.

[0089] The first connection electrode 1131E may be located at a position that does not overlap at all with the first external electrode 1141 in a planar perspective view. The first connection electrode 1131E is connected to the first external electrode 1141 via the internal wiring 4E and a first penetrating conductor 1151E extending from the first surface S1 toward the bottom surface 7.

[0090] The second connection electrode 1132E may be located at a position that does not overlap at all with the third external electrode 1143 in a planar perspective view. The second connection electrode 1132E is connected to the third external electrode 1143 via the internal wiring 4E and a second penetrating conductor 1152E extending from the first surface S1 toward the bottom surface 7.

[0091] The connection wiring 117E may have a first portion extending in a direction from the second external electrode 1142 toward the third external electrode 1143 in a plan view. The connection wiring 117E may have a second portion extending in a direction from the third external electrode 1143 toward the fourth external electrode 1144, and a third portion extending in a direction from the first external electrode 1141 toward the fourth external electrode 1144. In this way, the connection wiring 117E may be configured in a crank shape.

[0092] By configuring the connection wiring 117E in this manner, even if the first connection electrode 1131E is moved to a position closer to the second external electrode 1142 than the first connection electrode 1131D shown in Figure 14 and the second connection electrode 1132E is moved to a position closer to the fourth external electrode 1144 than the second connection electrode 1132D shown in Figure 14, the possibility of a short circuit between the connection wiring 117E and the first connection electrode 1131E and between the connection wiring 117E and the second connection electrode 1132E can be reduced, thereby improving the freedom of wiring design of the wiring board 100E.

[0093] The connection wiring 117E may extend from the second external electrode 1142 to the fourth external electrode 1144 in a plan view, and may have a first portion that curves and extends away from the first connection electrode 1131E. The connection wiring 117E may also have a second portion that curves and extends away from the second connection electrode 1132E. In this way, the connection wiring 117E may be configured in a curved S-shape.

[0094] In this way, the connection wiring 117E is configured to be bent or curved between the second external electrode 1142 and the fourth external electrode 1144. As a result, even if the first connection electrode 1131E is configured to be shifted toward the center from the corner of the bottom surface 7 of the recess 111, or if the first connection electrode 1131E is modified to have a shape that extends toward the center, or if the inner end of the first connection electrode 1131E is positioned closer to the center, the distance between the first connection electrode 1131E and the connection wiring 117E can be made longer than in the case of the straight connection wiring 117. This ensures insulation between the connection wiring 117E and the first connection electrode 1131E.

[0095] [Embodiment 7] FIG. 16 is a plan view of a wiring board 100F according to the seventh embodiment.

[0096] The wiring board 100F further includes a pillow portion 130. Two pillow portions 130 are provided in total, one at each corner of the recess 111 along one of the diagonal lines of the bottom surface 7 of the recess 111 in a plan view. The pillow portion 130 is an insulator that has a rectangular shape in a plan view and is convex with respect to the bottom surface 7 of the recess 111. The outer edge of the pillow portion 130 may be adjacent to the frame portion 110a.

[0097] The height of the pillow portion 130 may be approximately the same as the height of the upper surface of the first connection electrode 1131. Alternatively, the height of the pillow portion 130 may be approximately the same as the height of the first connection electrode 1131 plus the thickness of the bonding material 160.

[0098] The pillow portion 130 may be made of an insulating inorganic material, such as an aluminum oxide sintered body (alumina ceramics), an aluminum nitride sintered body, a mullite sintered body, or a glass ceramic sintered body.

[0099] The pillow portion 130 is located away from the wall surface of the recess 111. In other words, the pillow portion 130 may be a floating island. When the first and second connection electrodes 1131 and 1132 and the two pillow portions 130 are located on the floating island portion 2, respectively, the floating islands are located at the four corner portions, and the planar shapes of the four floating islands of the wiring substrate 100F are symmetrical, resulting in excellent flatness.

[0100] The piezoelectric vibration element can be mounted horizontally and stably by the pillow part 130. The pillow part 130 can reduce the possibility of the piezoelectric vibration element being damaged when the electronic device 10 receives an impact.

[0101] FIG. 17 is a plan view of a modified example of the wiring substrate 100F.

[0102] The wiring board 100F may include a pillow portion 130A. The pillow portion 130A is integrally connected to the frame portion 110a (see FIG. 1) of the insulating substrate 110, and two pillow portions 130A are provided, one at each corner of the recess 111 along one of the diagonal lines of the bottom surface 7 of the recess 111. Because the pillow portion 130A is integrally connected to the frame portion 110a, it is stronger than the pillow portion 130.

[0103] FIG. 18 is a plan view of another modified example of the wiring substrate 100F.

[0104] The wiring board 100F may include a pillow portion 130B. The pillow portion 130B is located away from the wall surface of the recess 111. In other words, the pillow portion 130B may be a floating island. Two pillow portions 130B are provided facing each other along the short side of the bottom surface 7 of the recess 111. The first and second connection electrodes 1131 and 1132 are located on the pillow portions 130B. The top surfaces of the first and second connection electrodes 1131 and 1132 may be flush with the pillow portion 130B. In other words, a part of either of the two pillow portions 130B may be the floating island portion 2 (see FIG. 6 ) where the first and second connection electrodes 1131 and 1132 are located, and the remaining part may function as a pillow portion that supports the piezoelectric vibration element. In other words, in the wiring board 100F, the first and second connection electrodes 1131 and 1132 may be located on the floating island portion 2, and the pillow portion 130B may be integrated with the floating island and extend in the direction of the short side of the bottom surface 7.

[0105] In this way, the pillow part 130B integrally includes the floating island part 2 where the first and second connection electrodes 1131 and 1132 are located, and therefore the pillow part 130B is even stronger than the pillow part 130A.

[0106] FIG. 19 is a plan view of yet another modified example of the wiring substrate 100F.

[0107] The wiring board 100F may include a pillow portion 130C. The pillow portion 130C differs from the pillow portion 130B shown in FIG. 18 in that it is integrated with the frame portion 110a. Two pillow portions 130C are provided facing each other along the short side of the bottom surface 7 of the recess 111. As such, the pillow portion 130C is integrated with the frame portion 110a, and therefore has even greater strength than the pillow portion 130B.

[0108] The invention according to the present disclosure has been described above based on the drawings and examples. However, the invention according to the present disclosure is not limited to the above-described embodiments. In other words, the invention according to the present disclosure can be modified in various ways within the scope of the present disclosure, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the invention according to the present disclosure. In other words, it should be noted that a person skilled in the art can easily make various modifications or corrections based on the present disclosure. It should also be noted that these modifications or corrections are included in the scope of the present disclosure. [Explanation of symbols]

[0109] 1 Electronic Module 2 Floating Island 3 Covering 4 Internal wiring 5 1st internal wiring 6 2nd internal wiring 7 Bottom 10 Electronic equipment 100 wiring board 110 insulating substrate 111 recess 113 Connecting electrode 114 External electrode 117 Connection wiring 130 Pillow part 150 Electronic Components 200 module board 1131 First connection electrode 1132 Second connection electrode 1141 1st external electrode 1142 2nd external electrode 1143 Third external electrode 1144 4th external electrode 1151 First through conductor 1152 Second through conductor S1 1st page S2 side 2 DL1 First diagonal DL2 Second diagonal

Claims

1. an insulating substrate having a rectangular shape in a plan view, the insulating substrate having a first surface, a second surface located opposite to the first surface, and a recessed portion opening to the second surface; an external electrode located on the first surface; a connection electrode located on the bottom surface of the recess, The external electrode is a first external electrode and a third external electrode located at opposite corners along a first diagonal line of the first surface and electrically connected to the connection electrode; a second external electrode and a fourth external electrode located at opposite corners along a second diagonal line of the first surface, the second external electrode and the fourth external electrode are connected by a connection wiring located inside the insulating substrate, a first through conductor that at least partially overlaps with the first external electrode in a planar perspective view and extends from the first surface toward the bottom surface; a second through conductor that at least partially overlaps with the third external electrode in a planar perspective view and extends from the first surface toward the bottom surface, The connection electrode is a first connection electrode connected to the first external electrode via the first through conductor; a second connection electrode connected to the third external electrode via the second through conductor, The wiring substrate, wherein the first connection electrode and the second connection electrode are located along the first diagonal line in a planar perspective view.

2. The wiring board according to claim 1 , wherein the first through conductor is located inside the first external electrode and offset from the center of the first connection electrode in a direction opposite to the inner wall of the recess in a planar perspective view.

3. The wiring board according to claim 2 , wherein at least a portion of the first through conductor is located outside the first connection electrode in a planar perspective view.

4. A convex floating island portion is located on the bottom surface of the recessed portion, The wiring board according to claim 1 , wherein the first connection electrode is located on the floating island portion.

5. a part of an end surface of the first through conductor on the bottom side is connected to the first connection electrode; The wiring board according to claim 1 , wherein an insulating coating is located between the remaining portion of the end face of the first through conductor and the bottom surface of the recess.

6. an internal wiring connected to an end face of the first through conductor on the bottom side, at least a portion of which extends along a plane substantially parallel to the first surface, and in which the first through conductor is located in the internal wiring when seen from above; The wiring board according to claim 1 , further comprising: a covering portion located between the internal wiring and the bottom surface and adjacent to the first connection electrode in a planar perspective view.

7. a first internal wiring connected to an end face of the first through conductor on the bottom side, at least a portion of which extends along a plane substantially parallel to the first surface, and in which the first through conductor is located in the first internal wiring when seen from above; a covering portion located between the first internal wiring and the bottom surface, the first through conductor being located therein in a planar perspective view; The wiring board according to claim 1 , further comprising: a second internal wiring that connects the first internal wiring and the first connection electrode.

8. The wiring board according to claim 1 , wherein the first connection electrode and the second connection electrode are positioned at positions that are point-symmetric with respect to the center of the second surface.

9. The wiring board according to claim 1 , wherein the connection wiring extends linearly from the second external electrode to the fourth external electrode in a plan view.

10. 2. The wiring board according to claim 1, wherein the connection wiring extends from the second external electrode to the fourth external electrode in a planar view, and has a first portion that curves and extends away from the first connection electrode, and a second portion that curves and extends away from the second connection electrode.

11. 2. The wiring board according to claim 1, wherein the connection wiring has, in a planar view, a first portion extending in a direction from the second external electrode toward the third external electrode, a second portion extending in a direction from the third external electrode toward the fourth external electrode, and a third portion extending in a direction from the first external electrode toward the fourth external electrode.

12. The wiring board according to claim 6 , wherein the first connection electrode and the second connection electrode have different shapes in a plan view.

13. A wiring board according to any one of claims 1 to 12; an electronic component connected to the wiring board; An electronic device comprising:

14. An electronic device according to claim 13; a module substrate connected to the electronic device; An electronic module comprising:

15. An insulating substrate having a rectangular shape in a plan view, the insulating substrate having a first surface, a second surface located opposite the first surface, and a recess opening into the second surface; an external electrode located on the first surface; a connection electrode located on the bottom surface of the recess, The external electrode is a first external electrode and a third external electrode located at opposite corners along a first diagonal line of the first surface and electrically connected to the connection electrode; a second external electrode and a fourth external electrode located at opposite corners along a second diagonal line of the first surface, the second external electrode and the fourth external electrode are located inside the insulating substrate and are connected by a connection wiring including a portion inclined with respect to the first surface, a first through conductor that at least partially overlaps with the first external electrode in a planar perspective view and extends from the first surface toward the bottom surface; a second through conductor that at least partially overlaps with the third external electrode in a planar perspective view and extends from the first surface toward the bottom surface, The connection electrode is a first connection electrode connected to the first external electrode via the first through conductor; a second connection electrode connected to the third external electrode via the second through conductor, The wiring substrate, wherein the first connection electrode and the second connection electrode are positioned at positions that are point-symmetric with respect to the center of the second surface.

Images