JP2017098070A - Electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic device having improved connection strength between a wiring board and a coaxial connector.SOLUTION: End portions of a plurality of grounding conductors 4 formed between layers of a plurality of insulating layers 1a are positioned outside a side surface of an insulating substrate 1 to form a side surface grounding electrode 7. A surface area of a portion joined to a second brazing filler metal 9b of the grounding conductor 4 including the side surface grounding electrode 7 is increased, so that joining strength between the second brazing filler metal 9b and the side surface grounding electrode 4 is improved to improve the connection strength between a wiring board 11 and a coaxial connector 10.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an electronic device in which a wiring board and a coaxial connector are connected to each other via a brazing material.

In recent years, electrical signals used in optical communication modules such as optical transceivers have been accelerated from 40 Gbps (gigabit per second) to 100 Gbps. Optical transceiver
Multiplexer having a function of bundling a plurality of low-speed electric signals transferred from an external module and switching to one or a plurality of high-speed signals, and a function of amplifying a current value of the electric signal transferred from the multiplexer It consists of a plurality of electronic devices such as drivers. A coaxial connector that is directly connected to a terminal of the electronic device or the like is used for electrical connection between the plurality of electronic devices.

  The coaxial connector includes an insulative main body, an inner conductor provided in the main body, and an outer conductor provided on the surface of the main body. Conventionally, a metal package has been used for an electronic device such as a driver. However, due to demands for cost reduction or miniaturization, etc., use of a surface-mount type wiring board is being studied. Accordingly, a surface mount type coaxial connector mounted electronic device in which a coaxial connector is electrically connected to a high speed transmission line (electrode) on a wiring board directly by a brazing material has been studied.

  In the coaxial connector-mounted electronic device, the inner conductor of the coaxial connector and the signal electrode formed at the end of the high-speed transmission path on the main surface of the wiring board are connected to each other. In addition, the outer conductor of the coaxial connector and the ground electrode disposed on both sides of the signal electrode on the main surface of the wiring board and spaced apart from the signal electrode are connected to each other.

JP 2009-218359 A Japanese Unexamined Patent Publication No. 2007-311505

  In the conventional coaxial connector-mounted electronic device, since only the signal electrode and the ground electrode having a relatively small area formed on the main surface of the miniaturized wiring board are connected to the coaxial connector via the brazing material, There was a problem that cracks were likely to occur in the brazing material due to stress. That is, improvement of the connection strength between the coaxial connector and the electrode of the surface-mounting type wiring board is a problem.

  As a countermeasure for such a problem, for example, as described in Patent Document 1, a connection conductor pattern formed by cutting out a via hole (through conductor) from the end to the side of the main surface of the wiring board, It is conceivable to connect the outer conductor of the coaxial connector via a brazing material.

  However, in the case of an electronic device having a via hole as described above, there is a possibility that a crack is generated from the end of the via hole in the wiring board due to the stress generated when the via hole is formed.

For example, as described in Patent Document 2, an end portion of an internal conductor layer (a ground electrode or the like) is exposed on the side surface of the wiring board, and the outer conductor of the coaxial connector is connected to the end portion through a brazing material. It is possible to connect them. However, in this case as well, the bonding area between the brazing material and the inner conductor layer (ground electrode, etc.) increases only by the thickness of the inner conductor layer exposed on the side surface of the wiring board. Connection strength with the substrate may be insufficient.

  An electronic device according to an aspect of the present invention includes an insulating substrate including a plurality of insulating layers stacked on each other, a signal that is disposed on a main surface of the insulating substrate and has an end located on an outer peripheral portion of the main surface. An electrode, a ground electrode having ends disposed on both sides of the signal electrode on the main surface of the insulating substrate, and an insulating substrate formed between layers of the plurality of insulating layers; A wiring board having a plurality of grounding conductors, each of which forms a side ground electrode, and a main body, and an inner portion provided inside the main body. A conductor and an outer conductor provided on an outer surface of the body; the inner conductor is electrically connected to the signal electrode; and the outer conductor is electrically connected to the ground electrode A coaxial connector; A first brazing material connecting an end portion of the electrode and the inner conductor of the coaxial connector, an end portion of the ground electrode and the plurality of side surface ground electrodes and the outer conductor of the coaxial connector; And a second brazing material.

  In an electronic device according to one aspect of the present invention, a plurality of side ground electrodes that are ends of a ground conductor are formed outside a side surface of an insulating substrate between layers of a plurality of insulating layers. Since the surface area of the side ground electrode, that is, the area to which the second brazing material is connected is large, the strength of the connection between the second brazing material and the side ground electrode (ground electrode) is relatively high. large. Thereby, the strength of connection between the ground electrode of the wiring board and the outer conductor of the coaxial connector via the second brazing material is improved as compared with the conventional electronic device. In addition, cracks and the like due to via holes are effectively suppressed. Therefore, it is possible to provide an electronic device with improved connection strength between the wiring board and the coaxial connector.

(A) is a principal part expansion perspective view which shows the electronic device of the 1st Embodiment of this invention, (b) is a principal part expansion which shows the wiring board contained in the electronic device of the 1st Embodiment of this invention. It is a perspective view. (A) is a perspective view which shows the coaxial connector contained in the electronic device of the 1st Embodiment of this invention, (b) is a side view of (a). It is the side view which looked at the electronic apparatus shown to Fig.1 (a) from the coaxial connector side. 2A is an enlarged cross-sectional view of a main part of the wiring board shown in FIG. 1B, and FIG. 2B is an enlarged cross-sectional view of the main part of the electronic device shown in FIG. (A) is a principal part enlarged plan view of the wiring board shown in FIG.1 (b), (b) is a side view of (a). (A) is a principal part expanded sectional view which shows the modification of Fig.4 (a), (b) is a principal part expanded sectional view which shows the modification of FIG.4 (b). (A) is a principal part expanded sectional view which shows the wiring board contained in the electronic device of the 2nd Embodiment of this invention, (b) is a principal part expansion which shows the electronic device of the 2nd Embodiment of this invention. It is sectional drawing. (A) is a principal part enlarged plan view of the wiring board shown to Fig.7 (a), (b) is a side view of (a). (A) is the principal part expanded sectional view which shows the modification of Fig.7 (a), (b) is the principal part expanded sectional view which shows the modification of FIG.7 (b).

  An electronic device according to an embodiment of the present invention will be described with reference to the accompanying drawings. Note that in the accompanying drawings, hatching may be applied even in a view other than a cross-sectional view in order to facilitate identification or the like.

(First embodiment)
FIG. 1A is an enlarged perspective view of a main part showing an electronic device according to the first embodiment of the present invention, and FIG. 1B shows a wiring board included in the electronic device according to the first embodiment of the present invention. It is a principal part expansion perspective view shown. FIG. 2A is a perspective view showing a coaxial connector included in the electronic device according to the first embodiment of the present invention, and FIG. 2B is a side view of FIG. FIG. 3 is a side view of the electronic device shown in FIG. 1A viewed from the coaxial connector side. 4A is an enlarged cross-sectional view of a main part of the wiring board shown in FIG. 1B, and FIG. 4B is an enlarged cross-sectional view of a main part of the electronic device shown in FIG. FIG. 5A is an enlarged plan view of a main part of the wiring board shown in FIG. 1B, and FIG. 5B is a side view of FIG. As shown in FIGS. 1 to 5, a coaxial connector 10 is connected to a wiring board 11 to basically constitute an electronic device 12. Note that the side surface shown in each of the above side views is a surface viewed from a direction perpendicular to the main surface of the wiring board 11. A part of the side surface of the wiring board 11 and a part of the side surface of the coaxial connector 10 face each other.

  The wiring substrate 11 is formed between an insulating substrate 1 including a plurality of insulating layers 1a stacked on each other, a signal electrode 2 and a ground electrode 3 disposed on the main surface of the insulating substrate 1, and a plurality of insulating layers 1a. And a plurality of ground conductors 4. The signal electrode 2 has an end located on the outer peripheral portion of the main surface of the insulating substrate 1. The ground electrode 3 has end portions that are arranged on both sides of the signal electrode 2 so as to be separated from the signal electrode 2 on the main surface of the insulating substrate 1. Further, the ground conductor 4 includes end portions (the end portions are not denoted by reference numerals) located outside the side surface of the insulating substrate 1, and these end portions form a plurality of side surface ground electrodes 7.

  The plurality of ground conductors 4 and the ground electrodes 3 are electrically connected to each other through grounding through conductors (so-called via conductors) (not shown) formed inside the insulating substrate 1, for example. By this electrical connection, the area of the conductor layer that becomes the ground potential is increased, and the ground potential is effectively stabilized.

  The coaxial connector 10 has a main body 13 made of an electrically insulating material, an inner conductor 5 provided inside the main body 13, and an outer conductor 6 provided on the outer surface of the main body 13. The inner conductor 5 is electrically connected to the signal electrode 2 and the outer conductor 6 is electrically connected to the ground electrode 3. The end portion of the inner conductor 5 is exposed for electrical connection with another conductor (described later).

  In addition, the electronic device 12 includes a first brazing material 9 a that electrically connects the end of the signal electrode 2 and the inner conductor 5 of the coaxial connector 10, a plurality of side ground electrodes 7 and the outer conductor of the coaxial connector 10. And a second brazing material 9b that is electrically connected to 6. Since the first brazing material 9a covers the entire surface of the signal electrode 2, the signal electrode 2 cannot be seen from the outside.

  Such an electronic device 12 is manufactured as follows, for example. That is, first, the wiring board 11 and the coaxial connector 10 having the above-described configuration are separately manufactured. Next, the end of the signal electrode 2 of the wiring board 11 and the inner conductor 5 (exposed end) of the coaxial connector 10 are aligned with each other with the first brazing material 9a interposed therebetween. Further, the ground electrode 3 and the side surface ground electrode 7 and a predetermined portion of the outer conductor 6 of the coaxial connector 10 are aligned with each other with the second brazing material 9b interposed therebetween. Thereafter, these are heated by an electric furnace or the like while being held in a predetermined positional relationship with a jig or the like. As a result, the wiring board 11 and the coaxial connector 10 are electrically and mechanically connected to each other via the first brazing material 9a and the second brazing material 9b, and the electronic device 12 is manufactured.

  In the electronic device 12, for example, the other end of a coaxial cable (not shown) whose one end is electrically connected to an external electric circuit (not shown) is connected to the coaxial connector 10, and the coaxial cable and the coaxial connector 10 are connected. The wiring board 11 and the external electric circuit are electrically connected to each other through the connector. The wiring board 11 may be further mounted with an electronic component (not shown) such as an IC or LSI, or may be electrically connected to another external electric circuit such as a multiplexer. In this case, a signal is transmitted and received between the external electric circuit and the electronic component.

  The inner conductor 5 and the outer conductor 6 of the coaxial connector 10 correspond to the coaxial transmission line of the coaxial cable, and the inner conductor 5 corresponds to the signal transmission conductive path in the coaxial transmission line. The conductor 6 corresponds to a conductive path for grounding.

  The electronic device 10 according to the embodiment has the above-described configuration. Since the side surface of the insulating substrate 1 has a plurality of side surface ground electrodes 7 protruding outward from the side surface, the second brazing material 9 and the side surface grounding are provided. Since the bonding area with the electrode 7 is increased, the bonding strength is relatively large. By joining the side ground electrode 7 and the second brazing material 9, the joining of the second brazing material 9 and the ground electrode 3 is effectively reinforced. As a result, the bonding strength between the ground electrode 3 of the wiring board 11 and the outer conductor 6 of the coaxial connector 10 via the second brazing material 9 is increased between the brazing material and the ground electrode in a conventional electronic device (not shown). It can improve rather than the strength of joining.

  In addition, due to the improvement of the joining strength, the joining of the signal electrode 2 of the wiring board 11 and the inner conductor 5 of the connector 10 via the first brazing material 9a is also reinforced. That is, the overall joint strength between the wiring board 11 and the coaxial connector 10 is effectively reinforced.

  In such an electronic device 12, for example, a stress generated when another member such as a coaxial cable (not shown) is connected to the coaxial connector 10, for example, a second solder having a larger area of adhesion to the side ground electrode 7. It can be relaxed with the material 9. Therefore, it is possible to provide the electronic device 12 in which the connection strength between the wiring board 11 and the coaxial connector 10 is improved.

  In the following description, members constituting the electronic device 12 such as the wiring board 11 and the coaxial connector 10 will be described with specific examples.

  The insulating substrate 1 functions as a base for arranging conductors such as the signal electrode 2, the ground electrode 3, and the ground conductor 4 in a predetermined positional relationship while being electrically insulated from each other as necessary. In the case of this example, the ground potential conductor such as the ground electrode 3 and the ground conductor 4 and the signal electrode 2 are electrically insulated from each other.

  The insulating substrate 1 has, for example, a polygonal plate shape such as a quadrilateral shape when viewed from above, and the surface and the inside of the upper surface and the like are spaces for arranging the conductors. The insulating substrate 1 may be a substrate whose corners are formed flat (so-called chamfered) as shown in FIG. The form of chamfering is not limited to a flat surface, but may be a curved surface such as an arc.

  The insulating substrate 1 includes a plurality of insulating layers 1a stacked on each other. The plurality of insulating layers 1a are made of, for example, a ceramic material such as a glass ceramic sintered body, an aluminum oxide sintered body, a mullite sintered body, an aluminum nitride sintered body, or a silicon nitride sintered body. . The insulating substrate 1 may be formed of a resin material such as an epoxy resin or a polyimide resin. 1, 3, and 5, only the portion where the insulating layer 1 a exists is shown for easy understanding, and the individual insulating layers 1 a are not shown.

In such an insulating substrate 1, for example, if each insulating layer is made of a glass ceramic sintered body, first, raw glass powder and ceramic powder such as silicon oxide and aluminum oxide are formed into a sheet shape together with an organic solvent and a binder. Forming a plurality of ceramic green sheets. Next, the laminated body produced by laminating these ceramic green sheets is fired at a temperature of about 900 to 1000 ° C. Through the above steps, the insulating substrate 1 made of a glass ceramic sintered body can be produced.

  On the main surface (upper surface in the example of FIG. 1 and the like) of the insulating substrate 1, a signal electrode 2 and a ground electrode 3 having end portions located on the outer peripheral portion of the main surface are arranged. The signal electrode 2 and the ground electrode 3 are connected to the corresponding ones of the internal conductor 5 and the external electrode 6 as coaxial transmission lines of the coaxial connector 10 as described above.

  The signal electrode 2 has, for example, a strip shape (elongated rectangular shape), and one signal electrode 2 is disposed on the main surface of the insulating substrate 1. The signal electrode 2 is a portion that is electrically connected to the internal conductor 5 that is a signal transmission path of the coaxial connector 10, and functions as a signal transmission conductive path in the wiring board 11.

  The ground electrode 3 has, for example, a strip shape (a long and narrow rectangular shape), and has end portions arranged on both sides of the signal electrode 2 away from the electrode 2 on the main surface of the insulating substrate 1. In other words, the two ground electrodes 3 are arranged with the signal electrode 2 interposed therebetween to form a coplanar transmission line. The signal electrode 2 and the ground electrode 3 each having a rectangular shape are arranged in parallel to each other, and electrical insulation between the signal electrode 2 and the ground electrode 3 is ensured.

  A plurality of insulating layers 1 a are formed between the insulating layers 1, and include end portions located outside the side surfaces of the insulating substrate 1. These end portions form a plurality of side surface ground electrodes 7. As described above, the ground conductor 4 is electrically connected to the ground electrode 3 by the via conductor or the like. The plurality of ground conductors 3 are provided to stabilize the ground potential in the wiring board 11. The plurality of ground conductors 3 are also provided for adjusting the characteristic impedance of the signal electrode 2.

  Further, the side surface ground electrode 7 which is an end portion of the ground conductor 4 has a side surface of the insulating substrate 1 in order to increase the bonding area between the second brazing material 9 and the ground conductor 4 (side surface ground electrode 7) as described above. Projecting outward. The side ground electrode 7 is a part formed so that the end portion of the ground conductor 4 protrudes outside from the interlayer of the insulating layer 1a.

  For example, copper, silver, palladium, gold, platinum, tungsten, conductor portions of the wiring board 11 such as the signal electrode 2, the ground electrode 3, the ground conductor 4 including the side surface ground electrode 7, and the via conductor are not used. It is made of a metal material such as molybdenum, nickel or cobalt. The conductor portion may be formed of an alloy material containing one or more of these metal materials as a main component, and may contain a glass component in order to control the shrinkage behavior. These metal materials can be disposed at a predetermined portion of the insulating substrate 1 by a method such as a metallizing method, a plating method, or a vapor deposition method.

  For example, if the conductor portion is made of copper deposited on the insulating substrate 1 by a metallization method, the conductor portion can be formed as follows. First, a metal paste prepared by kneading copper and glass powder together with an organic solvent and a binder is prepared. Next, this metal paste is applied in a predetermined pattern on the surface of the ceramic green sheet to be the insulating substrate 1 by a method such as screen printing. Thereafter, the conductor portions can be formed on the insulating substrate 1 by simultaneously firing them.

Note that the via conductor in the conductor portion is provided with a through hole in advance in a ceramic green sheet to be the insulating layer 1a of the insulating substrate 1 by a method such as mechanical drilling or laser processing. It can be formed by filling a metal paste into the inside and baking it.

  The side surface ground electrode 7 has, for example, the end portion of the ground conductor 4 more than the side surface of the insulating substrate 1 due to the difference in contraction behavior between the green sheet that is fired to become the insulating layer 1a and the metal paste that is fired to become the ground conductor 4. It can be formed by protruding outward. That is, at the time of firing, the contraction completion temperature of the ground conductor 4 (metal paste) is made lower than the contraction completion temperature of the insulating substrate 1, so that the insulating substrate 1 contracts even after the ground conductor 4 is contracted. Therefore, a structure in which the ground conductor 4 projects outward from the side surface of the insulating substrate 1 can be achieved. The protruding end portion of the ground conductor 4 corresponding to the contraction difference becomes the side electrode 7.

  The protruding length of the side ground electrode 7 from the side surface of the insulating substrate 1 may be, for example, about the thickness of the ground conductor 4 or longer. This effectively increases the area of the bonding of the second brazing material 9b to the side ground electrode 7 (ground conductor 4) compared to the case where the end surface of the ground conductor 4 is simply exposed on the side surface of the insulating substrate 1. be able to. That is, the bonding strength between the wiring board 11 and the coaxial connector 10 via the second brazing material 9b can be effectively increased.

  In the coaxial connector 10, for example, the inner conductor 5 as described above is provided inside a cylindrical main body 13, and the outer conductor 6 as described above is provided on the outer surface of the main body 13. The main body 5 is made of an electrically insulating material such as a resin material. The main body 13 is a part for maintaining the mutual positional relationship as a predetermined positional relationship in a state where the inner conductor 5 and the outer conductor 6 are electrically insulated from each other.

  The inner conductor 5 is a cylindrical member made of a metal material such as copper. The end portion of the inner conductor 5 is disposed so as to be exposed from the side surface of the coaxial connector 10 as described above. The exposed portion is electrically and mechanically connected to the signal electrode 2 by the first brazing material 9a.

  The outer conductor 6 is a member made of a metal material such as copper and having a shape and dimensions so as to cover the cylindrical main body 13 in the length direction. For example, a through portion (not indicated) corresponding to the main body 13 is provided. It is a block-shaped member.

  At the end of the outer conductor 6 on the side surface side of the coaxial connector 10, a convex portion protruding outside the side surface is provided (the projecting portion has no symbol). This convex portion is electrically and mechanically connected to the ground electrode 3 of the wiring board 11 via the second brazing material 9b.

  Further, the outer conductor 6 including the convex portion is joined to the ground electrode 3 and the side ground electrode 7 through the second brazing material 9b as described above. In this case, a fillet can be formed on the second brazing material 9b from the lower surface side of the convex portion to the side surface ground electrode 7. Stress can also be distributed along the fillet. Therefore, in the case of the outer conductor 6 having such a convex portion, it is advantageous for improving the connection strength between the wiring board 11 and the coaxial connector 10.

  The coaxial connector 10 can be manufactured by, for example, a method of combining (fitting) the main body 13, the inner conductor 5, and the outer conductor 6 each having a predetermined shape and size, which are separately prepared, in a predetermined positional relationship.

  The first brazing material 9a that electrically connects the end of the signal electrode 2 and the inner conductor 5 of the coaxial connector 10 is made of, for example, an alloy material such as Sn, Ag, Au, or Cu.

  The second brazing material 9b that electrically connects the plurality of side ground electrodes 7 and the outer conductor 6 of the coaxial connector 10 is made of the same material as the first brazing material 9a.

  The signal electrode 2 and the ground electrode 3 of the wiring board 11 and the inner conductor 5 and the outer conductor 6 of the coaxial connector 10 are aligned via the first brazing material 9a or the second brazing material 9b so as to correspond to each other. Thereafter, the electronic device 12 in which the wiring board 11 and the coaxial connector 10 are electrically and mechanically connected to each other can be manufactured by heating and cooling them in an electric furnace, oven, or the like.

  6A is an enlarged cross-sectional view of a main part showing a modification of FIG. 4A, and FIG. 6B is an enlarged cross-sectional view of a main part showing a modification of FIG. 4B. In these modified examples, the plurality of side surface ground electrodes 7 protrude outward at the upper end side of the side surface of the insulating layer 1a and extend along the side surface of the insulating layer 1a. That is, the plurality of side surface ground electrodes 7 have a portion that is thicker than the ground conductor 4 (a body portion located between the layers), that is, a portion that is relatively thick.

  In this modified example, the plurality of side surface ground electrodes 7 have an extending portion (the extension portion has no symbol) extending along the side surface of the insulating layer 1a (that is, the side surface of the insulating substrate 1). . Since the surface area of the side surface ground electrode 7 is increased by the amount of the extended portion, the surface area of the side surface ground electrode 7 can be increased to increase the bonding area of the second brazing material 9b.

  Further, in the configuration in which the side ground electrode 7 has an extending portion, the extending portion is buried in the insulating substrate 1. It can be considered that the side surface of the insulating substrate 1 (insulating layer 1a) is curved inward at a position corresponding to the extending portion, and a part of the side ground electrode 7 is disposed so as to fill the curved portion. it can.

  Thus, when the extension part of the side surface ground electrode 7 is buried in the insulating substrate 1, the mutual bonding area of the side surface ground electrode 7 and the insulating substrate 1 becomes larger. Therefore, the bonding strength between the side ground electrode 7 and the insulating substrate 1 is improved.

  In order to produce the wiring substrate 11 including the side ground electrode 7 having the above shape, for example, the following may be performed. That is, when the laminated body before firing including the green sheet that is fired to become the insulating layer 1a and the metal paste that is fired to become the ground conductor 4 is cut, the end portion of the ground conductor 4 is cut. Due to the shear stress at the time of cutting, the metal paste can be extended along the side surface of the insulating layer 1a. That is, an extended portion can be provided on the side ground electrode 7 formed of this metal paste. At the same time, a part of the side ground electrode 7 (metal paste) can be embedded in the insulating layer 1a (ceramic green sheet) by this shear stress.

  Each of the plurality of side ground electrodes 7 has an extending portion, and these extending portions extend in the same direction on the side surface of the insulating substrate 1. As a result, the distance between the extended portion of one side ground electrode 7 and the other side ground electrodes 7 (including the extended portion) positioned above and below it is kept relatively short and constant. It becomes easy. Therefore, the possibility that the bonding strength between the second brazing material 9b and the plurality of side surface ground electrodes 7 varies can be effectively reduced.

  In order to extend the extended portions of the plurality of side surface ground electrodes 7 in the same direction on the side surface of the insulating substrate 1, for example, as described above, the shear stress in one direction with respect to the end portion of the metal paste that becomes the ground conductor 4 Or the like.

  The length in which the extending part extends in the direction along the side surface of the insulating substrate 1 may be set to about 1/3 to 2/3 of the thickness of the insulating layer 1a, for example. It should be noted that the extending direction of each of the plurality of side ground electrodes 7 should be avoided from approaching the signal electrode 2 in order to ensure electrical insulation from the signal electrode 2.

(Second Embodiment)
FIG. 7A is an enlarged cross-sectional view showing a main part of the wiring board 11 included in the electronic device 12 according to the second embodiment of the present invention, and FIG. 7B is an electronic diagram according to the second embodiment of the present invention. 3 is an enlarged cross-sectional view showing a main part of the device 12. FIG. In FIG. 7, the same parts as those in FIGS. 1 to 5 are denoted by the same reference numerals.

  FIG. 8A is an enlarged plan view of the main part of the wiring board shown in FIG. 7A, and FIG. 8B is a side view of FIG. 8A.

  The electronic device 12 in the second embodiment and the wiring board 11 included in the electronic device 12 include a plurality of side surface ground electrodes 7 that are vertically adjacent to each other in at least a part of the side surface ground electrodes 7. A side-surface covered electrode 8 that integrally covers the side surface of the insulating substrate 1 is further provided. Further, the side covering electrode 8 is interposed between the side grounding electrode 7 and the second brazing material 9b. The electronic device 12 and the wiring board 11 in the second embodiment are the same as the electronic device 12 and the wiring board 11 in the first embodiment, except that the side surface covering electrode 8 is provided. Explanation of these similar points is omitted.

  In the electronic device according to the second embodiment, the side surface covering electrode 8 is formed between the end portion of the insulating substrate 1 and the coaxial connector 10 so as to surround the signal electrode 2 (end portion). Therefore, a space portion (gap) in which the second brazing material 9b is not interposed between the side surface ground electrodes 7 adjacent to each other between the side surface of the insulating substrate 1 and the side surface of the coaxial connector 10 hardly occurs. As a result, the electrical characteristics (high frequency characteristics) of the electronic device 12 can be improved.

  If such a gap is generated, resonance may occur between the side surface of the insulating substrate 1 and the side surface of the coaxial connector 10, and transmission loss due to this resonance may occur. That is, in the electronic device 12 of the second embodiment, the possibility of transmission loss due to such resonance is reduced, which is advantageous in improving electrical characteristics.

  FIG. 9A is an enlarged cross-sectional view of the main part showing a modification of FIG. 7A, and FIG. 9B is an enlarged cross-sectional view of the main part showing a modification of FIG. 7B. 9, parts similar to those in FIGS. 7 and 8 are given the same reference numerals.

  In the example shown in FIG. 9, for example, in the electronic device 12 of the second embodiment as shown in FIGS. 7 and 8, an extension portion similar to the modification of the electronic device 12 of the first embodiment described above is provided. This is an example.

  In other words, in the electronic device 12 including the side surface covering electrode 8, the side surface ground electrode 7 has an extending portion (a portion having a relatively large thickness) extending along the side surface of the insulating substrate 1. Further, the extending portion has a portion buried in the side surface of the insulating substrate 1. Further, the plurality of extending portions extend in the same direction. The entire side surface ground electrode 7 including the extending portion is covered with the side surface covering electrode 8.

  Also in this case, the effect of increasing the bonding area between the second brazing material 9b and the side surface ground electrode 7 due to the side surface ground electrode 7 having the extending portion can be obtained. Further, it is possible to obtain the effect of improving the bonding strength between the two due to the extension portion being buried in the insulating substrate 1. Further, it is possible to obtain an effect of reducing variation in bonding strength between the second brazing material 9b and the plurality of side surface ground electrodes 7. Further, since the bonding area between the side surface covering electrode 8 and the side surface ground electrode 7 is increased by the extension of the side surface ground electrode 7, the bonding strength between the side surface covering electrode 8 and the side surface ground electrode 7 is further improved. It can also be made.

  Further, since the side surface covering electrode 8 is formed, the possibility that resonance occurs between the side surface ground electrodes 7 adjacent in the vertical direction between the side surface of the insulating substrate 1 and the side surface of the coaxial connector 10 is reduced. , Electrical characteristics can be improved.

  The electronic device of the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the gist of the present invention. For example, the conductor portions such as the signal electrode 2 and the ground electrode 3 may be coated with plating layers (not shown) such as a nickel plating layer and a gold plating layer on the exposed surfaces. Further, such a plating layer may be applied to each of the wiring board 11 and the coaxial connector 10 before the electronic device 12 is manufactured.

  Further, at least one surface portion of the wiring board 11 and the coaxial connector 10 may be provided with a portion (not shown) such as a mark for aligning each other or a fitting portion of unevenness.

DESCRIPTION OF SYMBOLS 1 ... Insulating substrate 1a ... Insulating layer 2 ... Signal electrode 3 ... Ground electrode 4 ... Ground conductor 5 ... Internal conductor 6 ... External conductor 7 ... Side surface ground electrode 8 ... ..Side-coated electrode 9a..First brazing material 9b..Second brazing material
10 ... Coaxial connector
11 ... wiring board
12 ... Electronic device
13 ... Body

Claims (5)

An insulating substrate including a plurality of insulating layers stacked on each other, a signal electrode disposed on a main surface of the insulating substrate and having an end located on an outer peripheral portion of the main surface, on the main surface of the insulating substrate, A ground electrode having end portions arranged on both sides of the signal electrode and spaced apart from the signal electrode; and an end portion formed between the plurality of insulating layers and positioned outside the side surface of the insulating substrate. A wiring board having a plurality of ground conductors, each of the end portions forming a side ground electrode,
A main body, an inner conductor provided inside the main body, and an outer conductor provided on an outer surface of the main body, the inner conductor being electrically connected to the signal electrode, and the outer conductor A coaxial connector electrically connected to the ground electrode;
A first brazing material connecting the end of the signal electrode and the inner conductor of the coaxial connector, and connecting the end of the ground electrode and the plurality of side surface ground electrodes and the outer conductor of the coaxial connector An electronic device comprising: a second brazing material. In at least some of the plurality of side surface ground electrodes, further comprising a side surface covering electrode that integrally covers a plurality of side surface ground electrodes that are vertically adjacent to each other and a side surface of the insulating substrate;
The electronic device according to claim 1, wherein the side surface covering electrode is interposed between the side surface ground electrode and the second brazing material. The electronic device according to claim 1, wherein the plurality of side surface ground electrodes have an extending portion that extends along a side surface of the insulating substrate. The electronic device according to claim 3, wherein the extending portion is embedded in the insulating substrate. The plurality of side surface ground electrodes each have the extending portion, and the extending portion extends in the same direction on the side surface of the insulating substrate. An electronic device according to any one of the above.

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