JP7122939B2 - Wiring board and manufacturing method thereof - Google Patents

Description

TECHNICAL FIELD The present invention relates to a wiring board in which a bonding material for mounting is less likely to flow out from a concave portion formed by opening in a side surface of a board body made of an insulating material, and a manufacturing method thereof.

For example, when mounting a ceramic wiring board on the surface of a motherboard such as a printed circuit board, the inner wall surface and the bottom surface (ceiling surface, horizontal surface of the stepped portion) formed over the side surface and surface of the ceramic wiring substrate. The ceramic wiring board is mounted by disposing solder or a brazing material (joining material) between the side conductors provided along the surface of the motherboard and the electrode pads formed on the surface of the motherboard. there is
Furthermore, in order to respond to the demand for miniaturization and low profile of ceramic wiring boards, 3 connected to each other over the side surface and the peripheral side of the surface adjacent to the inner wall surface of the recess formed over the surface. A ceramic wiring board having two conductor layers and a method for manufacturing the same have also been proposed (see, for example, Patent Document 1).

However, as in the ceramic wiring board, the wall and bottom conductors formed along the inner wall surface and bottom surface of the recess opening over the side and surface of the substrate main body, and the electrode pads on the mother board side of the printed circuit board, etc. Alternatively, when a bonding material such as solder is provided between the lead terminals, part of the solder may flow out from the bottom surface of the recess. Such outflow of solder may lead to insufficient mounting strength of the wiring board, unstable electrical continuity between the wiring board and the printed board, or inadvertent short-circuiting.

Japanese Patent Application Laid-Open No. 2016-201434 (pages 1 to 16, FIGS. 1 to 10)

The present invention solves the problems described in the background art, and provides a wiring board in which a bonding material for mounting is less likely to flow out from a recess formed in the side surface of the board body, and the manufacture of the wiring board. The object is to provide a method.

Means for solving the problem and effects of the invention

In order to solve the above-described problems, the present invention was conceived of forming a protruding portion made of an insulating material along the outer edge of the bottom surface or ceiling surface of the recess on the side of the opening.
That is, the wiring board of the present invention (claim 1) is formed by laminating a plurality of insulating layers, has a rectangular outer shape in a plan view, and has a front surface and a back surface facing each other, and a wiring board positioned between the periphery of the front surface and the back surface. and a substrate main body having four side surfaces, and an opening formed in the side surface of the substrate main body, or formed so as to open over a pair of adjacent side surfaces, and intersecting the front surface and the rear surface of the substrate main body. a recess having an inner wall surface formed along a direction, a bottom surface or a ceiling surface parallel to the front and back surfaces of the substrate main body, a vertical metallized layer formed on the inner wall surface of the recess, and a bottom surface of the recess Alternatively, a wiring board comprising a metallized layer consisting of a horizontal metallized layer formed on the ceiling surface, wherein a protruding portion made of an insulating material is formed along the outer edge of the opening side of the bottom surface of the recess or the ceiling surface. characterized in that

According to the wiring board, the following effects (1) and (2) can be obtained.
(1) Since the ridge made of an insulating material is formed along the outer edge of the opening side of the bottom surface or the ceiling surface of the recess, the ridge is formed along the inner wall surface of the recess. In a space surrounded by the metallized layer and the horizontal metallized layer formed on the bottom surface or ceiling surface of the recess, the solder material is placed in a state in which the electronic component to be mounted or the lead terminal of the mother board to be mounted is brought close to the space. , When a bonding material such as solder or a conductive resin is filled, it is possible to reliably prevent the bonding material from flowing out of the recess. etc. can be installed.
(2) Since the bonding material such as the solder is less likely to flow out of the recess, it is possible to prevent accidental short-circuiting and reduce waste of the bonding material.

The insulating layer is made of ceramic or resin. Examples of the ceramic include high-temperature co-fired ceramic such as alumina and low-temperature co-fired ceramic such as glass-ceramic. Examples of the resin include epoxy resin. are exemplified.
Further, the substrate body may include a form having a cavity on at least one of the front surface and the back surface thereof, the cavity being open to the front surface or the back surface.
Furthermore, the front surface and back surface of the substrate body are designations indicating relative positions.
Further, in the recess, the bottom surface or the ceiling surface of the recess has a rectangular shape, a semicircular shape, a semi-elliptical shape, a quarter circle shape, or a substantially quarter oval shape in plan view. It includes the form that presents.
Further, the bottom surface and ceiling surface of the recess are also designations indicating relative positions.
When the insulating layer is alumina or the like, tungsten (hereinafter simply abbreviated as W) or molybdenum (hereinafter simply abbreviated as Mo) is applied to the metallized layer, and the insulating layer is glass-ceramic. In the case of resin, copper (Cu) or silver (Cu) is applied.
In addition, the ridges are made of the same ceramic or resin as the insulating layer, and are formed by, for example, screen-printing a paste containing them.

Further, in the present invention, the vertical metallized layer of the metallized layer is formed on a part of the inner wall surface of the recess in the width direction parallel to the front surface and the back surface of the substrate main body (claim 2). ) are also included.
According to this, since the vertical metallized layer corresponding to the required mounting strength is formed on a part of the inner wall surface in the width direction according to the area of the inner wall surface of the recess, it is possible to obtain an optimum structure according to the product specifications. It is possible to obtain the above effects (1) and (2) with a certain amount of bonding material.

Further, in the present invention, the horizontal metallized layer of the metallized layer is formed on the entire bottom surface or ceiling surface of the recess, or is spaced apart from the outer edge of the opening side of the bottom surface or ceiling surface. (Claim 3) is also included.
According to this, according to the area of the bottom or ceiling surface of the recess, the horizontal metallized layer corresponding to the required mounting strength is formed on the entire surface such as the bottom surface, or a portion spaced from the outer edge of the opening side of the bottom surface or the ceiling surface. , it is possible to obtain the above effects (1) and (2) with the optimum amount of bonding material according to product specifications.

In addition, in the present invention, the inner side surface facing the inner wall surface of the concave portion of the ridge portion has one concave surface that is concave toward the outer edge of the opening side in a plan view, or the substrate main body Also included is a wiring substrate (claim 4) having a plurality of concave surfaces spaced apart from each other along the width direction parallel to the front and back surfaces of the substrate.
According to this configuration, one or a plurality of concave surfaces that are concave toward the outer edge of the opening in a plan view are formed on the inner surface of the protruding portion that faces the inner wall surface of the concave portion, so that it is possible to mount the electronic component. It is possible to increase the bonding area between a bonding material such as solder used at times and the ridge portion. Therefore, the effects (1) and (2) can be obtained remarkably. Furthermore, it is possible to contribute to miniaturization and height reduction of the wiring board.

On the other hand, in the method for manufacturing a wiring board of the present invention (claim 5), a plurality of insulating layers are laminated, the front and back surfaces facing each other are rectangular in plan view, and the periphery of the front and back surfaces is provided. a substrate body having four side surfaces positioned therebetween; and a front surface and a back surface of the substrate body, which are formed to open on the side surfaces of the substrate main body or to open over a pair of adjacent side surfaces. a recess having an inner wall surface formed along a direction intersecting with the substrate body, a bottom surface or a ceiling surface parallel to the front and back surfaces of the substrate main body; a vertical metallization layer formed on the inner wall surface of the recess; A metallized layer made of a horizontal metallized layer formed on the bottom surface or the ceiling surface of the recess, and a protruding portion made of an insulating material formed along the outer edge of the opening side of the bottom surface or the ceiling surface of the recess. A method for manufacturing a wiring board, comprising: a first insulating layer formed by forming a vertical metallized layer along the thickness direction between the pair of surfaces on the inner wall surface of a through hole penetrating between the pair of surfaces facing each other; A second insulating layer provided with a horizontal metallized layer on one of the pair of surfaces and a ridge made of an insulating material along a planned cutting line to be singulated later on the one surface and a stacking step of stacking the first insulating layer and the second insulating layer so that the vertical metallization layer and the horizontal metallization layer are connected to each other. do.

According to the manufacturing method, the following effect (3) can be achieved.
(3) It is possible to efficiently manufacture the wiring board with a relatively small number of man-hours by adopting the form of taking a large number of wiring boards.
The first and second insulating layers are exemplified by ceramic green sheets, resin sheets, or resin films, for example.
Further, the ridges may be formed by firing at the same time as the metallized layer and the insulating layer, or may be formed by independent hardening treatment (cure treatment).
Furthermore, the manufacturing method can be applied mutatis mutandis to each wiring board.

FIG. 1(A) is a perspective view showing one embodiment of a wiring board according to the present invention, and FIG. 1(B) is a partially enlarged vertical cross-sectional view taken along line BB in FIG. (A) to (C) are partial enlarged vertical cross-sectional views similar to the above, showing metallized layers and ridges of different forms in the wiring substrate; (A) is a perspective view showing a wiring board having a configuration different from that described above, and (B) is a partially enlarged vertical cross-sectional view taken along line BB in (A). 2A to 2D are partial vertical cross-sectional views schematically showing manufacturing steps of the wiring board shown in FIG. 1; FIG. (A) and (B) are partially enlarged plan views showing ridges of a form further different from the above. (A) and (B) are partially enlarged perspective views showing recesses, metallized layers, and ridges of different forms from those described above.

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated.
FIG. 1(A) is a perspective view showing one embodiment of a wiring board 1a according to the present invention, and FIG. 1(B) is a partially enlarged vertical cross-sectional view taken along line BB in (A). .
As shown in FIGS. 1(A) and 1(B), the wiring board 1a has a rectangular (square or rectangular) outer shape in a plan view and has a front surface 3 and a rear surface 4 facing each other, and the front surface 3 and the rear surface 4. and a pair of concave portions 6a formed near the midpoints in the long side direction of the pair of opposing side surfaces 5 of the substrate body 2. and a metallized layer 10a formed for each recess 6a.
As shown in FIG. 1B, the substrate body 2 is formed by integrally laminating a pair (plurality) of upper and lower ceramic layers (insulating layers) c1 and c2. The main component is alumina.

The concave portion 6a is formed so as to open across the side surface 5 and the surface 3 of the substrate body 2, has a semi-elliptical shape in plan view, and extends in a direction intersecting the surface 3 and the back surface 4 of the substrate body 2. and a bottom surface 8a which is semi-elliptic in plan view and parallel to the front surface 3 and the rear surface 4. As shown in FIG. The bottom surface 8a serves as a ceiling surface 8a when the concave portion 6a is formed so as to open over the side surface 5 and the back surface 4 of the substrate body 2. As shown in FIG. That is, the bottom surface 8a and the ceiling surface 8a are relative names when the substrate body 2 is turned upside down, and the front surface 3 and the back surface 4 are also relative names in the same manner.
Further, as shown in FIGS. 1A and 1B, the metallized layer 10a is a vertical metallized layer formed at a position (part) of the inner wall surface 7a of the recess 6a excluding both horizontal end sides. 11a, a horizontal metallization layer 12a formed at a position on the inner wall surface 7a side of the bottom surface 8a of the recess 6a (that is, at a position spaced apart from the outer edge on the opening side), and the vertical metallization layer on the surface 3 of the substrate body 2. An upper metallized layer 13a is formed along the upper edge of 11a and has a semi-elliptical arc shape in plan view.
The vertical metallized layer 11a, the horizontal metallized layer 12a, and the upper metallized layer 13a are mainly made of W or Mo, and are electrically connected to each other. A nickel layer and a gold layer (neither is shown, the same applies hereinafter) are successively coated with a required thickness.

In addition, as shown in FIGS. 1(A) and 1(B), along the outer edge of the opening side of the bottom surface 8a of the recess 6a, there is made of alumina (insulating material), and the whole is linearly shaped along the horizontal direction. A ridge portion 15 is formed. The protruding portion 15 has a rectangular vertical cross section having an upper surface 16, an inner side surface 17 facing the inner wall surface 7a of the recess 6a, and an outer side surface 18 flush with the side surface 5 of the substrate body 2. and the bottom surface thereof is formed integrally with the ceramic layer c2. Incidentally, the protruding portion 15 has, for example, a total length of about 300 to 1000 μm and a thickness (height) of about 10 to 30 μm, and these sizes are appropriately selected according to the conditions of use.
The vertical cross section of the protruding portion 15 may be rectangular as described above, or may be semicircular or semielliptical with a curved top portion. In the case of such a semicircular shape, the inner side surface 17 is a curved surface of the protruding portion 15 on the side facing the inner wall surface 7a.

Further, as shown in FIG. 2A, the ridge portion 15 is formed by forming the lateral metallized layer 12a of the metallized layer 10a on the entire bottom surface 8a of the recess 6a, and It is good also as a form formed along the upper surface of the outer edge in.
Alternatively, as shown in FIG. 2(B), the outer edge of the horizontal metallized layer 12a is formed apart from the outer edge of the bottom surface 8a of the recess 6a, and the protruding portion 15 is formed between the horizontal metallized layer 12a and the above-mentioned metallized layer. It may be formed so as to extend over the bottom surface 8a, and a part of the bottom surface of the protruding portion 15 and the ceramic layer c2 may be directly joined.
Further, as shown in FIG. 2(C), the outer edge of the horizontal metallized layer 12a is formed apart from the outer edge of the opening side of the bottom surface 8a of the recess 6a, and the ridge 15 is formed on the horizontal metallized layer. 12a, and the bottom surface of the ridge portion 15 and the ceramic layer c2 may be directly connected and integrated.

In the wiring board 1a, as shown in FIG. 1(B), a plan view surrounded by the vertical metallized layer 11a and the horizontal metallized layer 12a of the metallized layer 10a and the inner side surface 17 of the protruding portion 15 is half. A lower end of a lead terminal (external connection electrode) 20 hanging down from the bottom side of an electronic component (not shown) to be mounted above the surface 3 of the substrate body 2 in the oblong recess 9 (a part of the recess 6a). In this state, a melted brazing material (joining material) 19 made of, for example, silver solder (Ag—Su alloy) as a joining material is applied over the recess 9 and over the upper metallized layer 13. Filling and placement are done.
As a result, the main portion of the brazing filler metal 19 is solidified in the recesses 9 formed by the protruding streaks 15 as shown in the drawing, and part of the brazing filler metal 19 wets and spreads on the upper surface side of the upper metallized layer 13 and solidifies. do. As a result, the brazing material 19 is prevented from flowing out of the side surface 5 of the substrate body 2 by the protrusion 15 .

Therefore, according to the wiring board 1a, the effects (1) and (2) can be reliably obtained.
Between the ceramic layers c1 and c2 in the substrate body 2, an inner layer wiring (not shown) is formed which is electrically connected to the metallized layer 10a, and at least one of the inner layer wiring and the ceramic layers c1 and c2 is connected. A form in which the metallized layer 10a and the electrode pads (not shown) formed on at least one of the front surface 3 and the back surface 4 of the substrate body 2 can be electrically connected through via conductors (not shown) penetrating therethrough. It is good as

FIG. 3(A) is a perspective view showing a wiring board 1b having a configuration different from that described above, and FIG. 3(B) is a partially enlarged vertical sectional view taken along line BB in (A). be.
As shown in FIGS. 3(A) and 3(B), the wiring board 1b is formed near the middle of the pair of side surfaces 5 of the board body 2 facing each other in the long side direction of the board body 2 similar to the above. and a metallized layer 10b formed for each of the recesses 6b.
The concave portion 6b is formed so as to open over the side surface 5 and the front surface 3 of the substrate main body 2, has a semicircular shape in a plan view, and is formed along a direction intersecting the front surface 3 and the rear surface 4 of the substrate main body 2. and a bottom surface 8b that is semicircular in plan view and parallel to the front surface 3 and the rear surface 4. As shown in FIG. The bottom surface 8b is also called a ceiling surface when the front surface 3 and the back surface 4 of the substrate body 2 are turned upside down.

As shown in FIGS. 3A and 3B, the metallized layer 10b is a vertical metallized layer formed at a position (part) of the inner wall surface 7b of the recess 6b excluding both ends in the horizontal direction. 11b, a horizontal metallization layer 12b formed at a position on the inner wall surface 7b side of the bottom surface 8b of the recess 6b, and a semicircular shape in plan view along the upper edge of the vertical metallization layer 11b on the surface 3 of the substrate body 2. and an upper metallized layer 13b formed in a ring shape. That is, the vertical metallized layer 11b is formed away from the outer edge of the opening side of the inner wall surface 7b of the recess 6b, and the horizontal metallized layer 12b is formed away from the outer edge of the bottom surface 8b of the recess 6b. there is
The vertical/horizontal/upper metallized layers 11b, 12b, and 13b are also made of W or the like, and their surfaces exposed to the outside are sequentially coated with a nickel layer and a gold layer.

Furthermore, along the outer edge of the opening side of the bottom surface 8b of the concave portion 6b, the same convex streak portion 15 made of the same alumina as described above and having a linear shape along the horizontal direction as described above is formed. The entire bottom surface of the ridge portion 15 is also formed integrally with the ceramic layer c2.
2(A) and 2(B), the horizontal metallized layer 12b is also formed on the entire bottom surface 8b of the recess 6b, and the lateral metallized layer 12b is formed on the opening side of the horizontal metallized layer 12b. Alternatively, the outer edge of the horizontal metallized layer 12b on the opening side is formed away from the outer edge of the opening side of the bottom surface 8b of the recess 6b, and the ridge portion 15 may be formed across the lateral metallized layer 12b and the bottom surface 8b.

In the wiring board 1b, as shown in FIG. 3(B), the plan view surrounded by the vertical metallized layer 11b and the horizontal metallized layer 12b of the metallized layer 10b and the inner side surface 17 of the protruding portion 15 is half. The lower end portion of the lead terminal 20 similar to that described above is inserted into the recess 9 (a part of the recess 6b) of an oval shape, and in this state, the brazing material 19 similar to that described above is filled and distributed in the recess 9. settings are made.
As a result, the brazing filler metal 19 is solidified in the depressions 9 formed by the protruding streaks 15, and part of it spreads and solidifies to the upper ends of the vertical metallized layers 11b. At the time of such mounting, the brazing material 19 is prevented from flowing out beyond the side surface 5 of the substrate body 2 by the ridges 15 .
Therefore, it is possible to obtain the effects (1) and (2) with certainty even with the wiring substrate 1b.
The upper end portion of the brazing material 19 may reach the upper surface of the upper metallized layer 13b as in FIG. 1(B).

Here, a method of manufacturing the wiring substrate 1a by taking a large number of pieces will be described.
A ceramic slurry containing alumina powder, a binder resin, a solvent, a plasticizer, etc., mixed in appropriate amounts in advance, is formed into a sheet with a required thickness by a doctor blade method, thereby forming two sheets as shown in FIG. 4(A). ceramic green sheets (insulating materials) g1 and g2 were prepared.
First, as shown in the figure, a through hole 21 oblong in plan view is formed between a pair of surfaces of a first green sheet (first insulating layer) g1, which will later become the ceramic layer c1, by punching or laser cutting. Formed by processing. After that, a conductive paste containing W powder or the like is applied to the surface around the through hole 21 , and a negative pressure is applied to the through hole 21 to obtain an inner wall surface of the through hole 21 . On the other hand, the same conductive paste as described above was applied with a substantially constant thickness to form an unfired vertical metallized layer 11a and an upper metallized layer 13a.

On the other hand, as shown in FIG. 4(A), on one surface of the second green sheet (second insulating layer) g2, which later becomes the ceramic layer c2, at a position corresponding to the through hole 21, a A conductive paste to be the horizontal metallized layers 12a was applied by screen printing to form a pair of unfired metallized layers 12a bilaterally symmetrically. Further, a ceramic (alumina) paste having a rectangular vertical cross section is screen-printed along an imaginary planned cutting line (plane) 23 which is a position corresponding to the through hole 21 and which is later divided into each wiring board 2. Then, the unfired ridges 25 were linearly formed (preparatory step).
Next, as indicated by the arrows in FIG. 4A, the first and second green sheets g1 and g2 were laminated and pressure-bonded along the thickness direction. As a result, as shown in FIG. 4(B), the first and second green sheets g1 and g2 are laminated, and along the planned cutting line 23, an elliptical shape is opened on one surface in plan view. a green sheet laminate 24 having a plurality of recesses 22, the ridges 25 located on the bottom surface of each recess 22, and a pair of horizontal metallized layers 12a connected to the vertical metallized layers 11a. (lamination process).

Further, the green sheet laminate 24 was fired. As a result, as shown in FIG. 4(C), the first and second green sheets g1 and g2 become integral ceramics c1 and c2, and the metallized layers 11a, 12a and 13a and the ridges are formed. A multi-piece ceramic mother substrate 26 in which 25 was fired simultaneously was obtained.
Subsequently, the ceramic mother substrate 26 is successively immersed in an electrolytic nickel plating bath and an electrolytic gold plating bath (not shown) to form a nickel layer and a nickel layer having a required thickness on the surfaces exposed to the outside of the metallized layers 11a, 12a, and 13a. Gold layers were applied sequentially.
Then, the ceramic mother substrate 26 was subjected to a dicing process or the like along the planned cutting lines 23 having a lattice diameter shape in a plan view, thereby performing a dividing step of dividing the ceramic mother substrate 26 into a plurality of wiring substrates 1a. As a result, as shown in FIG. 4(D), the mother substrate 26 is cut and divided along the planned cutting line 23, and the side surface 5 of the substrate main body 2 is formed on the trace of the planned cutting line 23. In addition, a plurality of wiring boards 1a in which half of the ridges 25 in the width direction are equal to each pair of ridges 15 can be obtained.

According to the method for manufacturing the wiring board 1a as described above, the effect (3) can be obtained.
The wiring board 1b can also be manufactured by the same method as the manufacturing method of the wiring board 1a, and the effect (3) can be obtained.
Furthermore, the wiring boards 1a and 1b including the respective forms of the ridges 15 and the lateral metallized layers 12a shown in FIGS. 2A and 2B can be easily manufactured by appropriately adjusting the preparation steps. can do.

FIG. 5(A) is a partially enlarged plan view showing a convex streak portion 15a having a form different from that described above.
As shown in FIG. 5A, the ridges 15a are arranged in the same manner as the ridges 15 in the recesses 6a and the metallized layer 10a of the wiring board 1a. The difference is that, in the protruding portion 15a, the inner side surface 17 facing the inner wall surface 7a of the recessed portion 6a is provided with one wide recessed surface 27 that is recessed toward the outer edge of the opening side of the recessed portion 6a in plan view. That is.
The provision of the concave surface 27 increases the contact area with the brazing material 19, thereby further increasing the mounting strength of the electronic components and the like, and contributing to the reduction in size and height of the wiring board 1a. becomes possible.
Incidentally, the protruding streak portion 15a can also be applied to the wiring board 1b.

FIG. 5(B) is a partially enlarged plan view showing a ridge portion 15b having a form different from that described above.
As shown in FIG. 5B, the ridges 15b are arranged in the same manner as the ridges 15 in the recess 6a and the metallized layer 10a of the wiring board 1a, and are different from the ridges 15. The point is that in the ridge portion 15b, the ridge portion 15b extends in the width direction parallel to the front surface 3 and the back surface 4 of the substrate body 2 on the inner side surface 17 facing the inner wall surface 7a of the recess 6a. direction) are provided with a plurality of narrow concave surfaces 28 that are concave toward the outer edge of the opening side of the concave portion 6a in plan view.
By providing a plurality of concave surfaces 28, the contact area with the brazing material 19 can be increased, and the volume of the protruding portion 15b can be sufficiently secured, so that the mounting strength of the electronic components and the like described above can be remarkably increased. In addition, it is possible to contribute to miniaturization and low profile of the wiring board 1a.
The protruding streak portion 15b can also be applied to the wiring board 1b.

FIG. 6A is a partially enlarged perspective view showing a concave portion 6c, a metallized layer 10c, and a protruding portion 15c in a form different from the above-described forms.
As shown in FIG. 6(A), the concave portion 6c is open over a pair of adjacent side surfaces 5 and the surface 3 of the same substrate body 2, and has a quarter circular shape when viewed from above. From an inner wall surface 7c formed along a direction that intersects the front surface 3 and the back surface 4 of the substrate body 2, and a bottom surface 8c that is quarter circular in plan view and parallel to the front surface 3 and the back surface 4. Become.
In addition, the metallized layer 10c includes a vertical metallized layer 11c formed with a substantially constant thickness along the inner wall surface 7c of the recess 6c at a position (part) of the inner wall surface 7c excluding both ends in the horizontal direction. , a horizontal metallization 12c formed on the bottom surface 8c of the recess 6c on the side of the vertical metallization layer 11c (that is, at a position spaced apart from the outer edge of the opening side) and having a circular shape with a plan view of 1/4; and an upper metallized layer 13c which is formed on the surface 3 of and has a quarter arc shape in plan view.
The vertical/horizontal/upper metallized layers 11c, 12c, and 13c are also made of W or Mo, and the surfaces exposed to the outside are sequentially coated with a nickel layer and a gold layer.

Further, the protruding portion 15c is made of alumina, is formed along the outer edge of the bottom surface 8c of the recessed portion 6c, and has an L shape in plan view, as shown in FIG. 6(A). The bottom surface of the ridge portion 15c is joined to the lower ceramic layer c2. The shape of the vertical cross section of the protruding streak portion 15c can be the same semicircular shape as that of the protruding streak portion 15, or the like.
The above effects (1) and (2) can also be obtained with a wiring board having the concave portion 6c, the metallized layer 10c, and the protruding portion 15c as described above.
In addition, in order to obtain the wiring board having the above configuration, in the preparatory step of the manufacturing method, the shape of the through hole 21 is made circular and the ridge portion 15c is formed to have a + shape in a plan view. It is possible to manufacture easily with the effect (3).
Also, one of the concave surfaces 27 and 28 may be formed on the inner surface of the protruding portion 15c.

FIG. 6(B) is a partially enlarged perspective view showing a concave portion 6d, a metallized layer 10d, and a convex portion 15d in a form different from each of the above-described forms. A pair of side surfaces 5 and a surface 3 adjacent to each other in the same substrate body 2 are opened, and in a plan view, a quarter elliptical shape or an L-shape consisting of two long and short sides, and the surface 3 of the substrate body 2 and an inner wall surface 7d formed along a direction intersecting with the back surface 4, and a bottom surface 7d having a quarter elliptical or rectangular shape in a plan view and parallel to the front surface 3 and the back surface 4. As shown in FIG.
The metallized layer 10d is a vertical metallized layer 11d formed with a substantially constant thickness along the inner wall surface 7d of the concave portion 6d at a position (part) of the inner wall surface 7d excluding both ends in the horizontal direction. and a horizontal metallization 12d formed on the bottom surface 8d of the recess 6d on the side of the vertical metallization layer 11d (that is, at a position spaced apart from the outer edge of the opening side) and having an oval or rectangular shape with a plan view of 1/4. and an L-shaped upper metallized layer 13d which is formed on the corner side of the inner wall surface 7d and which is L-shaped in plan view.
The vertical/horizontal/upper metallized layers 11d, 12d, and 13d are also made of W or the like, and the surfaces exposed to the outside are sequentially coated with a nickel layer and a gold layer.

Further, the protruding portion 15d is made of alumina, is formed along the outer edge of the bottom surface 8d of the recessed portion 6d as shown in FIG. ing. The bottom surface of the ridge portion 15d is also joined to the lower ceramic layer c2. The shape of the vertical cross section of the protruding streak portion 15d can be the same shape as that of the protruding streak portion 15. As shown in FIG.
The effects (1) and (2) can also be obtained with a wiring board having the concave portion 6d, the metallized layer 10d, and the protruding portion 15d as described above.
In addition, in order to obtain the wiring board of the above configuration, in the preparatory step of the manufacturing method, the cross section of the through hole 21 is formed into an elliptical or rectangular shape, and the protruding portion 25 has two long and short sides in a plan view. By forming it in a + shape, it is possible to manufacture easily with the effect (3).
Also, one of the concave surfaces 27 and 28 may be formed on the inner surface of the protruding portion 15d.

The present invention is not limited to each form described above.
For example, the substrate body 2 may be made of a high-temperature co-fired ceramic such as aluminum nitride or mullite, or a low-temperature co-fired ceramic such as glass-ceramic, or an epoxy-based resin layer, in addition to the alumina. In the latter case, copper or silver is applied as the conductor material such as the metallization layer 10a.
Further, the substrate body may have a front surface 3 and a rear surface 4 facing each other and having a rectangular outer shape in plan view, and a pair of side surfaces 5 having different lengths.
Further, the substrate main body 2 may have a form in which three or more ceramic layers are laminated, or a form in which a plurality of resin layers are laminated.
Further, the substrate body 2 may have a form in which at least one of the front surface 3 and the back surface 4 has a cavity opening to them. In such a form, the electrode pad electrically connected to the metallized layer may be formed on the bottom surface of the cavity.

Furthermore, the recesses 6a and 6b and the metallized layers 10a and 10b may be formed on all four side surfaces 5 of the substrate body 2, or may be formed on three side surfaces 5, or may be formed on one side surface 5. It is good also as a form which put together two or more.
Further, the concave portion disposed in the middle of the side surface 5 of the substrate body 2 may be trapezoidal or semi-elliptical in plan view.
Furthermore, the concave portions 6c and 6d and the metallized layers 10c and 10d may be arranged at four corners, three corners, one corner, or two corners located diagonally or adjacent to each other in the substrate body 2 in a plan view. good.
Further, when the substrate main body is made of resin, the same resin as the resin, the same type of resin, or a different type of resin that can be bonded is applied to the material of the ridges.
Further, the recesses 6a to 6b and the metallized layers 10a to 10d are individually arranged on both the side surface 5 and the front surface 3 and the side surface 5 and the rear surface 4 of the substrate body 2, and do they overlap each other in plan view? , may be separated from each other.
In addition, a lead terminal for mounting the wiring board on a mother board or the like may be joined to the recess through a joining material.

According to the present invention, it is possible to provide a wiring board in which a bonding material for mounting is less likely to flow out from a concave portion formed by opening in a side surface of a substrate body, and a manufacturing method thereof.

1a to 1d…………Wiring board 2……Board main body 3……Front surface 4……Back surface 5…… …………………… Sides 6a to 6d…………Recesses 7a to 7d…………Inner wall surfaces 8a to 8d…………Bottom/ceiling surfaces 10a to 10d………… Metallized layers 11a to 11d Vertical metallized layers 12a to 12d Horizontal metallized layers 15, 15a to 15d Convex portions 21 Through holes 23 …………Planned cutting line 27, 28…………Concave surface c1, c2…………Ceramic layer (insulating layer)
g1, g2 ………… Green sheet (insulating layer)

Claims (5)

a substrate body formed by laminating a plurality of insulating layers and having a rectangular outer shape in a plan view and having a front surface and a back surface facing each other, and four side surfaces positioned between the periphery of the front surface and the back surface;
an inner wall surface formed to open on a side surface of the substrate main body, or formed to open over a pair of adjacent side surfaces, and formed along a direction intersecting the front surface and the rear surface of the substrate main body; a recess having a bottom surface or a ceiling surface parallel to the front and back surfaces of the substrate main body;
A wiring board comprising a metallized layer composed of a vertical metallized layer formed on the inner wall surface of the recess and a horizontal metallized layer formed on the bottom surface or the ceiling surface of the recess,
A protruding portion made of an insulating material is formed along the outer edge of the opening side of the bottom surface or the ceiling surface of the recess,
A wiring board characterized by: The vertical metallization layer of the metallization layer is formed on a part of the inner wall surface of the recess in the width direction parallel to the front surface and the back surface of the substrate body,
The wiring board according to claim 1, characterized in that: The horizontal metallized layer of the metallized layer is formed away from the entire bottom surface or ceiling surface of the recess, or from the outer edge of the opening side of the bottom surface or ceiling surface.
3. The wiring board according to claim 1, wherein: Among the ridges, the inner side surface facing the inner wall surface of the concave portion has one concave surface that is concave toward the outer edge of the opening side in plan view, or has a width parallel to the front surface and the back surface of the substrate body. having a plurality of concave surfaces spaced apart from each other along a direction;
The wiring board according to any one of claims 1 to 3, characterized in that: A substrate body formed by laminating a plurality of insulating layers and having a rectangular outer shape in a plan view and having a front surface and a back surface facing each other and four side surfaces located between the periphery of the front surface and the back surface, the substrate body or an inner wall surface formed along a direction intersecting the front surface and the back surface of the substrate main body; The metallization consists of a recess having a bottom surface or a ceiling surface parallel to the front and back surfaces of the recess, a vertical metallization layer formed on the inner wall surface of the recess, and a horizontal metallization layer formed on the bottom surface or the ceiling surface of the recess. A wiring board manufacturing method comprising: a layer;
a first insulating layer in which a vertical metallized layer is formed along the thickness direction between the pair of surfaces on the inner wall surface of the through hole penetrating between the pair of surfaces facing each other;
A second insulation provided with a horizontal metallized layer on one of a pair of surfaces facing each other, and a protruding portion made of an insulating material along a planned cutting line to be singulated later on the one surface. a preparation step of preparing a layer;
a stacking step of stacking the first insulating layer and the second insulating layer so that the vertical metallized layer and the horizontal metallized layer are connected;
A method of manufacturing a wiring board, characterized by:

Images