JP6667184B2 - Wiring board manufacturing method - Google Patents

Description

The present invention can reduce the interval between a plurality of element mounting terminals formed on the surface of a substrate body made of ceramic, and is excellent in heat radiation of heat generated by an electronic component mounted above the plurality of element mounting terminals. method of manufacturing a wiring board.

For example, on the front and back surfaces of the ceramic substrate main body, front-side terminals and back-side terminals made of copper and formed by coating plating on the outer peripheral surface are individually formed, and between the front-side terminals and the back-side terminals. A via conductor made of tungsten or the like penetrating the ceramic substrate is formed, and a nickel plating layer, an adhesion layer made of titanium, and a molybdenum are formed between both end faces of the via conductor and the front side terminal and the back side terminal. There has been proposed a ceramic substrate having three intermediate layers and a method of manufacturing the same (for example, see Patent Document 1).
According to the ceramic substrate, it is possible to prevent corrosion at a connection portion between the ceramic substrate main body and the front / back surface side terminals, so that the connection reliability is excellent.

However, in the above-described ceramic substrate, for example, when a light-emitting element such as an LED having a large calorific value is mounted above the front-side terminal, heat generated from the light-emitting element is generated by the front and rear surfaces made of copper. A via conductor made of tungsten or the like is located between the side terminals, and furthermore, the plating layer, the adhesion layer, and the intermediate layer are located at the interface between the via conductors. There is a problem that the heat of the element cannot be radiated to the outside.
Moreover, since the front-side terminals and the rear-side terminals do not have a sufficient thickness, heat generated by a light-emitting element mounted above the front-side terminals is dissipated on the front and rear sides of the ceramic substrate body. There was also a problem that it was difficult to do so.

  Further, in order to manufacture the ceramic substrate, a conductive paste containing tungsten or the like is filled in each through hole penetrating the upper and lower two-layer ceramic green sheets, the green sheets are laminated and fired, and the ceramic substrate body and Form via conductors. Next, a nickel layer is coated on both end surfaces of the via conductor by a plating step, and an intermediate layer made of titanium and an adhesion layer made of molybdenum are formed on both surfaces of the ceramic substrate body including the nickel layer by sputtering or the like. Coat sequentially. Then, after forming a predetermined resist pattern on the intermediate layer, the front side terminal and the rear side terminal made of copper are formed by electrolytic copper plating inside the through hole of the resist pattern. Finally, there is a problem that a relatively complicated combination of a plurality of manufacturing steps of forming a coating plating layer on the surface of the front and back side terminals is required, and the manufacturing cost is likely to increase.

JP 2014-120738 A, (pages 1 to 20, FIGS. 1 to 16)

The present invention solves the problems described in the background art, and even when a light emitting element or the like having a large calorific value is mounted above a plurality of element mounting terminals formed on the surface of a substrate body made of ceramic, even if the light emitting element manufacturing accuracy is reliably obtained by a relatively simple process combination of the wiring board with an improved heat dissipation by quickly heat transfer on the back surface side of and substrate body can dissipate the heat generated on the surface side of the substrate body It is an object to provide a method.

Means for Solving the Problems and Effects of the Invention

In order to solve the above-mentioned problems, the present invention provides an element mounting terminal and a connection terminal which are individually formed on a front surface and a back surface of a substrate body made of ceramic, and a via conductor which conducts therebetween and penetrates the substrate body. The idea was to form the three members from one piece of copper.
That is, a method of manufacturing a wiring board according to the present invention (Claim 1) includes a substrate body made of ceramic and having a front surface and a back surface, a plurality of element mounting terminals made of copper formed on the surface of the substrate body, A plurality of connection terminals made of copper formed on the back surface of the substrate main body, and a plurality of copper terminals penetrating between the front surface and the back surface of the substrate main body and individually connecting the element mounting terminals and the connection terminals. A method of manufacturing a wiring board comprising: a via conductor ; a hole forming step of forming a plurality of via holes in a ceramic green sheet; a step of coating a metallized layer on an inner wall surface of the via hole; and an inner wall surface of the via hole. Baking the green sheet covered with a metallized layer to form a substrate body; and an inner peripheral side of the metallized layer covered on the inner wall surface of the via hole. A step of coating a nickel layer, an adhesion layer forming step of forming a metal adhesion layer including a titanium layer and a copper layer on the front and back surfaces of the substrate main body, and a front and back surface of the substrate main body having the metal adhesion layer formed thereon A resist forming step of forming a resist layer of a required pattern, and a via conductor made of copper on the inside and inside of the via hole of the substrate body and on the front and back surfaces of the substrate body surrounded by the resist layer, an element mounting terminal, And an electrolytic copper plating step of integrally forming the connection terminals .

According to the method for manufacturing a wiring board, the following effect (7) can be obtained .
(7) The wiring board having the effects (1) to (6) described later can be accurately and reliably manufactured by a combination of a plurality of relatively simple steps .
The method for manufacturing the wiring board is mainly performed in a multi-cavity mode .
The hole forming step is performed by punching or laser processing .
Further, the resist forming step is performed by a photolithography technique, and specifically, includes a step of attaching a dry film, and a step of performing patterning by exposing and developing the dry film .
In addition, the step of forming the adhesion layer is performed by sputtering or CVD .

Further, in the present invention, after the electrolytic copper plating step, a peeling agent is brought into contact with the resist layer to remove the resist layer, and the metal adhesion layer exposed on the front surface and the back surface of the substrate main body. And a plating step of coating a nickel film and a gold film on surfaces exposed to the outside of the element mounting terminals and the connection terminals, and a method of manufacturing a wiring board (claim 2). It is .
According to the method of manufacturing a wiring board, in addition to the effect (7), corrosion of the surface of the element mounting terminal and the connection terminal exposed to the outside can be reliably prevented (effect (8)) .

The wiring board obtained by the present invention is composed of a ceramic body, a substrate body having a front surface and a back surface, a plurality of element mounting terminals made of copper formed on the surface of the substrate body, and a wiring board formed on the back surface of the substrate body. A plurality of connection terminals made of copper, and a plurality of via conductors made of copper penetrating between the front surface and the back surface of the substrate body and individually connecting the element mounting terminals and the connection terminals. Wherein the element mounting terminals, connection terminals, and via conductors are made of integral copper .

According to the wiring board having the relatively simple configuration and structure as described above, the following effect (1) is obtained .
(1) Since the three elements of the element mounting terminal, the connection terminal, and the via conductor are formed of integral copper, the amount of heat generated follows a plurality of element mounting terminals formed on the surface of the substrate body. When a large light-emitting element or the like is mounted, heat generated from the light-emitting element can be quickly transmitted to the back side of the substrate body and radiated to the outside .

The ceramic forming the substrate body is, for example, a high-temperature fired ceramic such as alumina or a low-temperature fired ceramic such as glass-ceramic .
In addition, the substrate main body may have a form in which a plurality of ceramic layers are laminated and a wiring for plating or the like is formed in any of the ceramic layers, in addition to the form composed of a single ceramic layer .
Further, the element mounting terminal is a terminal on which an element is to be mounted later .
Further, the height (thickness) of the element mounting terminal is in a range of 100 to 500 μm from the surface of the substrate main body .
The element mounting terminal and the connection terminal may have any shape such as a rectangle (rectangle or square) having four corners at four corners in a plan view, a circle, an ellipse, an ellipse, and a hook (hook). Take shape .
Further, the cross section of the via conductor has a circular shape, an elliptical shape, an elliptical shape, a rectangular shape, or the like .
In addition, the expression “consisting of one piece of copper” indicates that the metal is composed of the same or similar copper metal structure (including a plating layer) .

The wiring board also includes a mode in which the height of the element mounting terminal from the surface of the substrate main body is twice or less the thickness of the substrate main body .
According to the wiring board of the above embodiment, the following effect (2) can be exhibited .
(2) By increasing the thickness and size of the element mounting terminal relative to the substrate main body, heat generated from the light emitting element can be effectively radiated to the outside even on the surface side of the substrate main body. It becomes possible. Further, when the height of the element mounting terminals from the surface of the substrate main body is set to not less than half the thickness of the substrate main body, the above-mentioned effect (2) can be surely exhibited .
In addition, since the capacity for transmitting heat from the light emitting element is increased, the effect (1) can be exhibited more efficiently .
In a region where the height of the element mounting terminal from the surface of the substrate main body exceeds twice the thickness of the substrate main body, it is difficult to manufacture the element mounting terminal itself, and the cost may be excessively high. Therefore, it is excluded .

Further, the wiring board includes a mode in which a distance between adjacent element mounting terminals on the surface of the substrate body is equal to or less than a thickness of the element mounting terminal .
According to the wiring board of the above aspect, the distance between adjacent element mounting terminals is the same distance (length) as the thickness of the element mounting terminals or smaller than this distance, and the distance between the adjacent element mounting terminals is reduced. Since it is formed on the surface of the main body, the following effects (3) and (4) can be surely exhibited, and the effect (2) can be promoted .
(3) Since the space between adjacent element mounting terminals is as narrow as possible on the surface of the substrate main body, when the light emitting element is mounted across adjacent element mounting terminals, the light emission is prevented. By disposing the element mounting terminals near the center of the element, heat from the light emitting element can be transmitted more efficiently. Therefore, the effects (1) and (2) can be remarkably exhibited .
(4) The distance between adjacent element mounting terminals on the surface of the substrate body is as narrow as possible. Accordingly, mounting of electronic components such as light emitting elements having a relatively small size can be facilitated and performed with high accuracy, and the size of the present wiring board itself can be easily reduced .
When the distance between the adjacent element mounting terminals exceeds the thickness of the element mounting terminals, the effect (3) is hardly obtained because the two element mounting terminals are excessively separated from each other. This range is excluded .

Further, the wiring board includes an embodiment in which an interval between adjacent element mounting terminals on the surface of the board body is 100 μm or less .
According to the wiring board of the above aspect, since the interval between the adjacent element mounting terminals is as narrow as 100 μm or less, the effect (3) can be surely exhibited, and the effect (1) is obtained. , (2) can be further promoted .
If the distance between the adjacent element mounting terminals exceeds 100 μm, the effect (3) is hardly obtained as described above, and this is excluded .

Further, the wiring board includes a mode in which a metallized layer is formed along the inner wall surface of the via hole between the via conductor penetrating the board body and the via conductor .
According to the wiring board of the above aspect, since the metallized layer made of tungsten or molybdenum is formed along the inner wall surface of the via hole, the via conductor formed inside the via hole and made of copper is made of ceramic. A structure in which the substrate body is firmly adhered can be obtained (effect (5)) .
The effect (5) can be more remarkably exhibited by further providing a nickel layer on the outer peripheral side (the center axis side of the via hole) of the metallized layer .

In addition, the wiring board has a titanium layer and a copper layer between the bottom surface of the element mounting terminal and the front surface of the substrate body, and between the bottom surface of the connection terminal and the back surface of the substrate body. The form in which the metal adhesion layer containing is formed is also included .
According to the wiring board of the above aspect, since the metal adhesion layer is formed between the element mounting terminal and the front surface of the substrate main body, and between the connection terminal and the back surface of the substrate main body, The element mounting terminals can be firmly adhered to the surface of the substrate body, and the connection terminals can be firmly adhered to the back surface of the substrate body (effect (6)) .
The metal adhesion layer has a three-layer structure in which a titanium layer, a molybdenum layer, and a copper layer or a titanium layer, a tungsten layer, and a copper layer are stacked in this order from the front and back sides of the substrate body. It is good .

Plan view of a wiring board of an embodiment that obtained Ri by the present invention. FIG. 2 is an enlarged vertical sectional view taken along the line XX in FIG. 1. (A)-(F) is the schematic which shows the manufacturing process of the said wiring board by this invention . FIGS. 3A to 3D are schematic views showing a manufacturing process following FIG. (A), (B) is a vertical sectional view which shows the wiring board of a different form which can be obtained by this invention .

Hereinafter, an embodiment for carrying out the present invention will be described.
Figure 1 is a plan view showing a wiring substrate 1a of a form that obtained Ri by the present invention, FIG. 2 is an enlarged vertical sectional view taken along the arrow line X-X in FIG.
As shown in FIGS. 1 and 2, the wiring board 1a is composed of upper and lower two ceramic layers (ceramics) c1 and c2, and has a front surface 3 and a back surface 4; A pair (plurality) of element mounting terminals 5 made of copper (Cu), a plurality of connection terminals 6 made of copper formed on the back surface 4 of the substrate body 2, and a surface 3 of the substrate body 2 And a plurality of via conductors made of copper penetrating between the back surface and connecting the element mounting terminals and the connection terminals individually.

The substrate body 2 is formed by integrally laminating the ceramic layers c1 and c2 made of a high-temperature fired ceramic such as alumina, and between the ceramic layers c1 and c2, tungsten (hereinafter, referred to as W) or molybdenum ( (Hereinafter, referred to as Mo) and a wiring for plating (not shown) having a predetermined pattern is formed. Incidentally, the substrate body 2 has a substantially square shape of about 1.5 mm × about 1.5 mm in plan view, and has a thickness T1 of about 150 μm.
The element mounting terminal 5, the connection terminal 6, and the via conductor 8 are formed of integral copper and are continuous with each other. These are formed almost simultaneously by an electrolytic copper plating process described later.

Further, as shown in FIG. 2 and a partially enlarged view shown at the tip of the arrow, the via conductor 8 is provided inside the via hole 7 penetrating between the front surface 3 and the back surface 4 of the substrate body 2. 7, a metallized layer 17 of about 5 μm in thickness made of W or Mo formed along the inner wall surface, and a nickel layer (hereinafter referred to as Ni layer) 18 of about 2 μm in thickness located on the inner peripheral side thereof. It is formed via an internal adhesion layer 16 made of. Therefore, the via conductor 8 is firmly adhered to the ceramic layers c1 and c2 constituting the substrate transformation 2.
The via conductor 8 has a cylindrical shape with a diameter L2 of about 100 μm to about 400 μm. For example, the via conductor 8 may have a square pillar shape with one side having the above dimensions and rounded corners. As shown in FIG. 1, three via conductors 8 are provided in parallel between the upper and lower element mounting terminals 5 and the connection terminals 6 in FIG. 2, but one or two via conductors 8 are provided. Or four or more may be provided. Furthermore, they may or may not be provided in parallel.

Further, the element mounting terminal 5 and the connection terminal 6 are formed integrally with the via conductor 8 near the center of the bottom surface thereof as shown in FIG. 2 and a partial enlarged view indicated by the arrow. In addition, a metal adhesion layer 12 is interposed between the bottom surface of the element mounting terminal 5 and the front surface 3 of the substrate main body 2 and between the bottom surface of the connection terminal 6 and the rear surface 4 of the substrate main body 2. The metal adhesion layer 12 is formed from the front surface 3 side or the back surface 4 side of the substrate main body 2 in the order of a titanium layer (hereinafter referred to as a Ti layer) 13, a Mo layer 14, and a copper layer 15. , W layer 14, and copper layer 15 in this order. Therefore, the element mounting terminals 5 and the connection terminals 6 are firmly adhered to the front surface 3 or the back surface 4 of the substrate body 2.
The overall thickness of the metal adhesion layer 12 including the Ti layer 13, the Mo layer 14 or the W layer 14, and the copper layer 15 is about 0.1 to about 1 μm.

As shown in FIG. 2 and a partially enlarged view shown at the end of the arrow, the Ni film 10 on the underside and the gold film on the surface layer are provided on the surfaces exposed to the outside of the element mounting terminals 5 and the connection terminals 6. 11 is coated. Therefore, the element mounting terminal 5 and the connection terminal 6 are hardly corroded even by an external influence.
The thickness of the Ni film 10 is about 1 to about 10 μm, and the thickness of the gold film 11 is about 0.2 to about 2 μm.
As shown in FIG. 2, the height (thickness, T2) of the element mounting terminal 5 from the surface 3 of the substrate main body 2 is equal to or more than half the thickness T1 of the substrate main body 2, and The thickness of the substrate body 2 is relatively thick, not more than twice (T2 / T1 ≦ 2) the thickness T1. Further, as shown in FIG. 2, the thickness T2 of the element mounting terminal 5 is formed to be about 1.0 to 2 times the thickness of the connection terminal 6. That is, the thickness T2 of the element mounting terminal 5 and the thickness of the connection terminal 6 are the same, or the element mounting terminal 5 is formed to be thicker.

In addition, the distance L1 between the pair of adjacent element mounting terminals 5 on the surface 3 of the substrate body 2 is equal to or less than the thickness T2 of the element mounting terminals 5 (a range L1 / T2 ≦ 1), which is a relatively narrow (short) distance. Incidentally, the distance L1 between the adjacent element mounting terminals 5 is 100 μm or less.
Further, as shown in FIG. 2, above the pair of element mounting terminals 5, an electronic component 19 having a relatively large heating value such as a light emitting element such as an LED or a power semiconductor element is mounted by a known method. .
According to the wiring board 1a having the above configuration and structure, the effects (1) to (6) can be reliably achieved.

Hereinafter, a method for manufacturing the wiring board 1a according to the present invention will be described with reference to FIGS. FIGS. 3 and 4 show a part to be the wiring board 1a in the multi-cavity mode.
An appropriate amount of alumina powder, a predetermined resin binder, a solvent, a plasticizer, and the like are mixed in advance to prepare a ceramic slurry (not shown), and the slurry is formed into a sheet shape by a doctor blade method. As shown, two layers of ceramic green sheets (hereinafter simply referred to as green sheets) g1 and g2 were produced.
Next, punching was performed for each predetermined position in the green sheets g1 and g2 to form a via hole 7 having a circular cross section as shown in FIG. 3 (B) (a hole forming step).
Note that laser processing may be performed instead of the punching processing. Further, before or after the perforating step, a conductive paste containing W powder or Mo powder is screen-printed on one of the bottom surface of the green sheet g1 and the top surface of the green sheet g2 to form a predetermined pattern. Was formed.

Next, the same conductive paste as above is applied to the inner wall surface of each of the via holes 7 in the green sheets g1 and g2 by suction printing from one of the openings of the via holes 7 by negative pressure, so that the entire surface is cylindrical. Of unfired metallized layer 17.
Further, as shown in FIG. 3C, the green sheets g1 and g2 communicate with each other along the axial direction of the via holes 7 and with the metallized layers 17 along the axial direction of each other. After being continuously laminated and pressed, the green sheets g1 and g2 were fired. As a result, at the same time that the metallized layer 17 was fired, the green sheets g1 and g2 became a laminate of the integral ceramic layers c1 and c2, and became the substrate body 2 having the front surface 3 and the back surface 4.

Next, the inner peripheral surface of the metallized layer 17 is subjected to electrolytic Ni plating which is immersed in a required Ni plating bath and is energized by utilizing the wiring for plating or the like, as shown in FIG. As described above, the inner peripheral surface of the metallized layer 17 was covered with the Ni layer 18. As a result, as shown in FIGS. 3 (C) and 3 (c), a cylindrical internal adhesion layer 16 was formed on the inner wall surface of each via hole 7. After the step of coating the Ni layer 18, the substrate body 2 was subjected to a known sintering process.
Next, by subjecting the front surface 3 and the back surface 4 of the substrate main body 2 to sputtering, as shown in FIGS. 3D and 3D, a Ti layer 13, a Mo layer 14, and a copper layer 15 are sequentially formed in a predetermined manner. And a metal adhesion layer 12 composed of these three layers and having a total thickness of about 0.1 to about 1 μm is formed by opening the respective via holes 7 on the front surface 3 and the back surface 4 of the substrate body 2. It was formed individually on the entire surface except for it.
FIGS. 3C and 3D are enlarged views of dashed-dotted lines c and d in FIGS. 3C and 3D, respectively.

Further, as shown in FIG. 3 (E), on each of the metal adhesion layers 12 formed on the front surface 3 and the back surface 4 of the substrate main body 2, for example, an acrylic photosensitive resin is formed and has a thickness. Different dry films 20 and 21 were attached.
Next, for example, a step of irradiating (exposure) the above-mentioned dry films 20 and 21 with ultraviolet rays by a predetermined burn and then a step of contacting with a predetermined developer is performed as shown in FIG. Thus, the dry films 20 and 21 became the resist layers 22 and 23 having the openings 24 and 25 of the required pattern in plan view. On the bottom surface of each of the opening holes 24 and 25, the metal adhesion layer 12 and the via hole 7 opening near the center thereof were exposed.

Then, the copper wiring is immersed in a required copper plating bath and electrolytic copper plating is conducted by using the plating wiring, and as shown in FIG. 4A, the inside of the via hole 7 and the resist layer 22, Inside each of the 23 opening holes 24 and 25, an element mounting terminal 5, a connection terminal 6, and a via conductor 8 made of copper integrated with each other were formed. At this time, the thicknesses of the element mounting terminal 5 and the connection terminal 6 corresponded to the depth of each of the opening holes 24 and 25 of the resist layers 22 and 23. The inner diameter of the inside of the via hole 7 was previously set to be not more than twice the thickness T2 of the copper portion between the element mounting terminal 5 and the connection terminal 6. Thereby, it is possible to prevent a situation in which a gap is formed in the via hole 7 and the opening holes 24 and 25.
Further, the surfaces of the resist layers 22 and 23 and the surfaces of the copper of the element mounting terminals 5 and the connection terminals 6 were polished (surface adjusted) so as to have the same height.

Next, as shown in FIG. 4B, a stripping step of removing the resist layers 22 and 23 was performed by bringing the resist layers 22 and 23 into contact with a required stripper.
Next, a predetermined etching solution for etching the copper layer 15, the Mo layer 14, and the Ti layer 13 constituting the metal adhesion layer 12 with respect to the metal adhesion layer 12 exposed to the outside by removing the resist layers 22 and 23. Were sequentially contacted. At this time, masking (not shown) was performed on the surfaces of the element mounting terminals 5 and the connection terminals 6.
As a result, as shown in FIG. 4 (C), the metal adhesion layer 12 is removed, and only the pair of element mounting terminals 5 and the metal adhesion layer 12 located on the bottom surface side are formed on the surface 3 of the substrate body 2. And a plurality of connection terminals 6 and only the metal adhesion layer 12 located on the bottom side thereof are left on the back surface 4 of the substrate body 2.

Then, a plating step of sequentially performing electrolytic Ni plating and electrolytic gold plating was performed on the surfaces of the element mounting terminals 5 and the connection terminals 6 exposed to the outside.
As a result, as shown in FIGS. 4D and 4D, the exposed surfaces of the element mounting terminal 5 and the connection terminal 6 are covered with the anticorrosion film 9 composed of the Ni film 10 and the gold film 11 of the above-described thicknesses. Thus, the wiring board 1a was obtained. FIG. 4D is an enlarged view of a dashed line portion d in 4D.
In addition, since the above manufacturing process is in the form of multiple pieces, the step of dividing into a plurality of wiring boards 1a was performed immediately after this.
According to the method of manufacturing the wiring board 1a according to the present invention described above, the effects (7) and (8) that can accurately and reliably manufacture the wiring board 1a that can exhibit the effects (1) to (6) can be obtained. I was able to play.

FIG. 5A is a vertical sectional view similar to the above, showing a different form of the wiring board 1b that can be obtained by the present invention .
As shown in FIG. 5A, the wiring board 1b includes the same substrate body 2 as described above, and a pair of element mounting terminals 5 formed on the front surface 3 thereof. In the figure, a plurality of connection terminals 6 are formed near the left and right ends. Furthermore, the right and left ends of the front surface 3 of the substrate main body 2 on the bottom surface of each of the element mounting terminals 5 and the center of the rear surface 4 of the substrate main body 2 on the bottom surface of each of the connection terminals 6 are illustrated. In between, the same via conductor 8 as described above is formed of copper integrally with the element mounting terminal 5 and the connection terminal 6.

According to the wiring board 1b as described above, the pair of element mounting terminals 5 are adjacent to each other with a small interval L1 on the front surface 3 of the substrate main body 2, and the plurality of connection terminals 6 are formed on the back surface 4 of the substrate main body 2. Are located apart from each other. Therefore, when the electronic component 19 is mounted above the pair of element mounting terminals 5 later, the heat generated from the electronic component 19 can be dissipated on the surface 3 side of the substrate main body 2 and the integrated copper can be removed from the integrated copper. Through the via conductors 8 and the connection terminals 6, the radiation can also be efficiently performed on the back surface 4 side of the substrate body 2. Moreover, since the plurality of connection terminals 6 are separated from each other on the back surface 4 of the board body 2, the miniaturized main wiring board 1b can be easily mounted on the surface of a mother board (not shown) such as a printed board. It is also possible to do.
Therefore, the effects (1) to (6) can be obtained also by the wiring board 1b.

FIG. 5B is a vertical sectional view similar to the above, showing a wiring board 1c of still another form which can be obtained by the present invention .
As shown in FIG. 5B, the wiring board 1c has the same substrate body 2 as described above, and a pair of element mounting terminals 5 adjacent to each other at the surface 3 with the space L1 therebetween. A plurality of connection terminals 6 are formed on the entire surface, and a plurality of connection terminals 6 are formed on the back surface 4 of the substrate main body 2 at right and left ends near the end in the drawing. Further, the element mounting terminals 5 and the connection terminals 6 are connected to each other by integral copper via via conductors 8 which individually penetrate the substrate main body 2 at positions near the left and right side surfaces in the drawing.
With the wiring board 1c as described above, the effects (1) to (6) can be exhibited, and the mounting on the motherboard described above can be easily performed.
Note that the wiring boards 1b and 1c as described above can be manufactured in the same manner as the method of manufacturing the wiring board 1a described above.

The present invention is not limited to the embodiments described above.
For example, the ceramic constituting the substrate body 2 may be a high-temperature fired ceramic such as mullite or aluminum nitride, or a low-temperature ceramic such as glass-ceramic, instead of the alumina.
Further, the substrate body 2 may have a form of a single ceramic layer or a form in which three or more ceramic layers are integrally laminated.
Further, the device mounting terminals 5 are provided in a pair on the surface 3 of the substrate main body 2, but four, six, or eight or more terminals are provided side by side with the spacing L 1 adjacent to the surface 3. It is good also as a form which did.

In FIGS. 2, 5A and 5B, the plurality of connection terminals 6 are illustrated as a pair of left and right sides. It is good also as a form.
In addition, in the method of manufacturing the wiring board 1a, the step of forming the metallized layer 17 on the inner wall surface of the via hole 7 is performed by metal spraying (metallicon) spraying a molten metal powder. The adhesion layer forming step to be formed may be performed by CVD.

According to the present invention, even when a light emitting element or the like having a large amount of heat is mounted above a plurality of element mounting terminals formed on the surface of the substrate body made of ceramic, heat generated from the light emitting element is transferred to the front side of the substrate body. in a wiring board with an improved heat dissipation property in also can quickly heat transfer on the back side of the dissipation can and the substrate body, it is possible to reliably provide a high accuracy obtained production method by a combination of relatively simple steps with Become.

1a to 1c: wiring board, 2: board body,
3 ... front side, 4 ... back side,
5 ……………………………………………………………………………………… Connection terminal
7 ... via hole, 8 ... via conductor,
10 Nickel film 11 Gold film
12 ... metal adhesion layer 13 ... titanium layer
15 Copper layer 17 Metallized layer
18 Nickel layer 22, 23 Resist layer,
c1, c2: ceramic layer, g1, g2: green sheet

Claims (2)

A substrate body made of ceramic and having a front surface and a back surface, a plurality of element mounting terminals made of copper formed on the surface of the substrate body, and a plurality of connection terminals made of copper formed on the back surface of the substrate body, A method of manufacturing a wiring board, comprising: a plurality of via conductors made of copper penetrating between a front surface and a back surface of the substrate body, and individually connecting the element mounting terminals and the connection terminals,
A hole forming step of forming a plurality of via holes in the ceramic green sheet,
A step of coating a metallization layer on the inner wall surface of the via hole,
Firing the green sheet coated with a metallized layer on the inner wall surface of the via hole, a firing step of forming the substrate body,
A step of coating a nickel layer on the inner peripheral side of the metallized layer coated on the inner wall surface of the via hole,
An adhesion layer forming step of forming a metal adhesion layer including a titanium layer and a copper layer on the front and back surfaces of the substrate body,
On the front and back surfaces of the substrate body on which the metal adhesion layer is formed, a resist forming step of forming a resist layer of a required pattern,
An electrolytic copper plating step of integrally forming a via conductor made of copper, element mounting terminals, and connection terminals on the inside and outside of the via hole of the substrate body and on the front and back surfaces of the substrate body surrounded by the resist layer, Has,
A method for manufacturing a wiring board, comprising: After the electrolytic copper plating step,
A stripping step of contacting a stripping agent with the resist layer to remove the resist layer,
An etching step of removing the metal adhesion layer exposed on the front and back surfaces of the substrate body,
A plating step of coating a nickel film and a gold film on a surface exposed to the outside of the element mounting terminals and the connection terminals,
The method for manufacturing a wiring board according to claim 1 , wherein:

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