JP2012151260A - Multi-piece divided wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-piece divided wiring board having a product area in which a plurality of wiring boards are arrayed in a matrix in a plane and a selvage part on which electrodes for plating are formed on a lateral surface, in which a thickness of a metal plating coat coated on a conductor part is uniform though the wiring board is arranged at any portion in the product area.SOLUTION: A multi-piece divided wiring board comprises a product area Pa in which a plurality of insulation layers s1-s3 are laminated and a plurality of wiring boards are arrayed in a matrix in a plane, a selvage part 5 in which the similar insulating layers s1-s3 are laminated and which is located along an outer periphery of the product area Pa, electrodes for plating formed on a lateral surface of the selvage part 5 and tie bars 15 for plating electrically connecting the electrodes for plating with connection wiring extended from conductor parts of a plurality of wiring boards located on the outermost side in the product area Pa. A thickness of the tie bar 15 for plating becomes thicker as a tapered shape 15t with distance from a location 16 adjacent to the electrode for plating toward a location 17 apart from the electrode for plating.

Description

  In the present invention, a plurality of wiring boards in which a plurality of wiring boards are arranged vertically and horizontally, and a metal plating is relatively uniformly coated on a conductor portion formed on the front surface, the back surface, or the bottom surface of each cavity of each wiring board. Regarding the substrate.

  The multi-cavity wiring board is composed of a product area in which a plurality of wiring boards are arranged vertically and horizontally, and a rectangular frame-shaped ear part positioned around the product area, and a pair of ear edges facing each other at the ear part. A plurality of plating electrodes for sequentially covering, for example, Ni plating and Au plating are formed on a conductor portion such as a pad exposed on the surface of each wiring board on the outer surface of each of the wiring boards. . Between the electrode for plating and the conductor portion of the wiring board located on the outermost side of the product area, the surface formed on the surface of the ear part or inside is electrically connected through a rectangular frame-shaped plating tie bar. It is possible. Then, in a state where the rod electrode for plating is inserted into the concave groove for each of the plating electrodes and brought into contact, the Au plating or the like is applied to the surface of each conductor portion by sequentially immersing in a predetermined plating solution bath. It is covered.

By the way, the ear side of the ear part where the electrode for plating is formed and the ear side where the connection wiring extends from each conductor part of the wiring board located on the outermost side of the product region are adjacent to each other at right angles. In this case, the plating current is likely to flow excessively in the plating tie bar located at the corner portion where the two ear sides are connected at right angles.
Therefore, the surface of the plating tie bar near the corner is coated with a relatively thick plating film such as Au, while the conductor portion of the wiring board located near the center in the product area is plated. Since the coating becomes relatively thin and easy to coat, there is a problem that the thickness of the plating coating becomes non-uniform depending on the wiring board at a position in the product region. In order to solve such a problem, among the ears having a rectangular frame shape, the width of the plating tie bar located in the region for each corner part of the ear part is made larger than the width of the plating tie bar located in the other straight part. A wide multi-cavity wiring board has been proposed (see, for example, Patent Document 1).

  However, in the multi-cavity wiring board of Patent Document 1, the ear edge of the ear portion where the electrode for plating is formed, and the ear edge where the connection wiring extends from each conductor portion of the wiring board located on the outermost side of the product area, However, it is difficult to apply to a multi-piece wiring board having a common form. In addition, the conduction resistance to the wiring board located at the center of the product area relatively far away must be larger than that of the outermost wiring board in the product area located relatively close to the plating electrode. As a result, the thickness of the metal plating film coated on the conductor part of the wiring board located on the outermost side of the product region is thicker than the thickness of the metal plating film coated on the conductor part of the wiring board on the center side, There has been a problem that the plating film has a large variation, and the quality becomes unstable among a plurality of separated wiring boards.

Japanese Patent Laid-Open No. 2006-1000054 (pages 1 to 11, FIG. 1)

  The present invention has both a product region in which a plurality of wiring boards are arranged vertically and horizontally and an ear portion on which an electrode for plating is formed on the outer surface, and is a wiring substrate at any position in the product region. Another object of the present invention is to provide a multi-piece wiring board in which the thickness of a metal plating film coated on a conductor portion located on the surface thereof is uniform.

Means for Solving the Problems and Effects of the Invention

In order to solve the above-mentioned problems, the present invention is directed to increasing the thickness of a plating tie bar from a position close to the plating electrode toward a position away from the plating electrode in the multi-piece wiring board of the above-described form. Inspired by the idea.
That is, the multi-cavity wiring board of the present invention (Claim 1) is a product in which a plurality of insulating layers are laminated, and a plurality of wiring boards having a rectangular shape in a plan view along the thickness direction are arranged along the length and breadth. A region, an insulating layer laminated in the same manner as described above, an ear portion that is located along the outer periphery of the product region and has a rectangular frame shape in plan view, and a plating electrode formed on the outer surface of the ear portion; A plating tie bar formed on the ear portion and electrically conducting between the electrode for plating and connection wires extending from conductor portions of a plurality of wiring boards located on the outermost side in the product region. The thickness of the plating tie bar is increased from a position close to the plating electrode toward a position away from the plating electrode.

According to this, the plating tie bar that conducts between the electrode for plating and the connection wiring extending from the conductor portions of the plurality of wiring boards located on the outermost side in the product region is the plating plate. The ear portion is formed so that the thickness increases from a position close to the electrode toward a position away from the plating electrode. As a result, the current from the plating electrode is less likely to immediately flow to the wiring board close to the electrode, so that the outermost wiring board in the product area located relatively close to the plating electrode and the plating electrode A difference in conduction resistance due to the length of the conduction path can be suppressed or reduced with respect to the wiring board located on the center side of the relatively distant product region.
Accordingly, since the plating current flows relatively uniformly to the wiring board at any position in the product area through the plating electrode, the plating tie bar, and the connection wiring, the surface of each wiring board, etc. This is a multi-piece wiring board in which the conductor portion located at is covered with a metal plating film whose thickness is approximate.
In addition, while the thickness of the plating tie bar changes, the width in plan view is constant, so that the width dimension of the ear portion forming the plating tie bar can be suppressed.

The insulating layer is a high-temperature fired ceramic layer such as alumina, a low-temperature fired ceramic layer including a glass-ceramic layer, or a resin layer such as epoxy.
The product region includes both a form in which a plurality of wiring boards are directly adjacent to each other vertically and horizontally and a form in which a plurality of wiring boards are arranged vertically and horizontally through an insulating layer.
Further, the plating tie bar is formed on the front surface, the back surface, or the interlayer of the plurality of insulating layers, in which a plurality of insulating layers are laminated.
Further, the plating tie bar and the conductor portion of each wiring board located on the outermost side in the product area are individually connected by the dedicated connection wiring and are adjacent in the product area. The conductor parts for each wiring board to be connected are also connected by the same connection line.
Further, the conductor portion of the wiring board means an internal wiring layer, a connection terminal (pad) on the front or back surface, a pad located on the bottom surface of the cavity, a through-hole conductor, or a conductor frame for sealing located on the surface surrounding the cavity. Etc.
Further, a virtual cutting plane is located between the product region and the ear portion and between adjacent wiring boards in the product region, or a cross-section substantially V-shaped along the cutting plane. Are formed on at least one of the front surface and the back surface.
In addition, the portion of the plating tie bar having a large thickness includes a form protruding outward from the front or back surface of the ear part or a form entering the inside of the ear part.

In the present invention, the thickness of the plating tie bar is gradually increased from a position close to the plating electrode to a position away from the plating electrode, or is gradually increased. A multi-piece wiring board (claim 2) is also included.
According to this, the thickness of the plating tie bar is formed on the ear portion so as to increase gradually or stepwise from a position close to the plating electrode to a position away from the plating electrode. ing. As a result, since a relatively uniform plating current flows to the wiring board at any position in the product area, a multi-cavity wiring board in which a metal plating film of equivalent thickness is coated on the conductor portion of each wiring board and It has become. Moreover, the conductive paste is gradually increased in thickness, for example, in a taper shape, between the front surface, back surface, or internal insulating layer of the ear portion formed by laminating a plurality of insulating layers made of a ceramic layer or the like. It is possible to form the tie bar for plating without greatly increasing the number of steps or making it complicated by printing and forming so that the thickness changes stepwise like a step, for example. it can.
The “gradual” means that the thickness increases in a tapered or curved pattern, for example, from a position close to the plating electrode to a position away from the plating electrode. In addition, the “stepwise” means that the thickness is increased in a stepped pattern having a plurality of steps, for example.

Further, according to the present invention, a plurality of the plating electrodes are formed on the outer surface of the ear portion, and the thickness of the plating tie bar connecting between two adjacent plating electrodes is determined by the thickness of each plating electrode. Also included is a multi-piece wiring board (Claim 3) that is thinnest at a position close to and thickest at a position farthest from each plating electrode.
According to this, in the product region, the outermost wiring board that is relatively close to one of the two plating electrodes that are adjacent to each other at the same edge side of the ear portion, and any plating electrode is relatively Since the difference in conduction resistance due to the length of the conduction path is small regardless of whether it is separated from the center side wiring board, a metal plating film whose thickness is approximated to the conductor portion of each wiring board is covered. It is a multi-circuit board.

In the present invention, a plurality of plating electrodes are formed for each of a pair of ear sides facing each other in plan view, and two adjacent plating electrodes are connected for each ear side. The width of the plating tie bar may include a multi-piece wiring board that is thinnest at a position close to each plating electrode and thickest at a position farthest from each plating electrode.
In this case, a plurality of plating electrodes are formed for each pair of ear edges facing each other across the product region in the ear portion, and the two plating electrodes adjacent to each other at the ear edges are connected. The thickness of the tie bar is the thinnest at a position close to each plating electrode and is the thickest at a position farthest from each plating electrode. As a result, since a relatively uniform plating current is applied to the wiring board at any position in the product area, a large number of conductors on each wiring board covered with a metal plating film whose thickness is approximated. It can be a wiring board.

The top view which shows the multi-piece wiring board of one form by this invention. FIG. 2 is a vertical sectional view taken along line XX in FIG. 1. The expanded sectional view which expanded the left part in FIG. FIG. 2 is a vertical sectional view taken along the line YY in FIG. 1. The vertical sectional view similar to FIG. 4 which shows the tie bar for plating of a different form. Furthermore, the same vertical sectional view as FIG. 4 which shows the tie bar for plating of a different form. The vertical sectional view similar to FIG. 4 which shows the tie bar for plating of another form. FIG. 5 is a vertical sectional view similar to FIG. 4 showing another embodiment of a plating tie bar. The vertical sectional view similar to FIG. 4 which shows the tie bar for plating of another form. The partial top view which shows the application form of the multi-piece wiring board of FIG. FIG. 11 is a vertical sectional view taken along the line ZZ in FIG. 10. The vertical sectional view similar to FIG. 11 which shows the tie bar for a different form. The vertical sectional view which shows the multi-piece wiring board of a different form. FIG. 14 is a partial plan view taken along the line U-U in FIG. 13. FIG. 15 is a schematic vertical sectional view taken along line VV in FIG. 14.

Hereinafter, modes for carrying out the present invention will be described.
FIG. 1 is a plan view showing a multi-piece wiring board 1a according to an embodiment of the present invention, FIG. 2 is a vertical sectional view taken along line XX in FIG. 1, and FIG. FIG. 4 is an enlarged cross-sectional view in which the left side portion is enlarged, and FIG.
As shown in FIGS. 1 to 3, the multi-piece wiring board 1 a has a front surface 2 and a back surface 3 and is formed by laminating three ceramic layers s <b> 1 to s <b> 3, and is rectangular in plan view along the thickness direction. A product region Pa in which a plurality of wiring boards p exhibiting the above are arranged along the vertical and horizontal directions while being spaced apart from each other, and the same ceramic layers s1 to s3 as described above are laminated, and are located along the outer periphery of the product region Pa and are planar The ear part 5 has a rectangular frame shape, and the same electrode 6 for plating formed on the outer surface 4 of the pair of left and right ear sides 5 in FIG. The electrode 6 for plating is a substantially semi-cylindrical body along the inner wall surface of the concave groove 7 provided on the outer side surface 4 of the ear portion 5 in a plan view.
The ceramic layers s1 to s3 are mainly composed of alumina, for example.
Moreover, the broken line in FIG. 2, FIG. 3 has shown the virtual cutting planned surface cf.
Further, the front surface 2 and the back surface 3 are common to the product region Pa and the ear portion 5.

As shown in FIG. 1, a pair of left and right long edges 5 of the ears 5 on the surface 2 of the ceramic layer s1 are formed with a pair of plating tie bars 15 facing each other. A pair of connection tie bars 18 are formed on the side edge 5 so as to face each other.
As shown in FIG. 4, the plating tie bar 15 is connected to the central portion of the plating electrode 6 through the connection line 14 and is located closest to the plating electrode 6 from the position 16 closest to the plating electrode 6. It is formed so that the thickness increases outwardly toward the distant position 17 in a tapered shape (gradually) 15t. The plating tie bar 15 located between the plating electrodes 6 and 6 adjacent to each other at the same edge 5 is also thickened toward the position 17 farthest from each plating electrode 6. On the other hand, the upper and lower connecting tie bars 18 that connect the upper and lower end positions 17, 17 of the plating tie bar 15 have a band shape with a constant width and thickness.

As shown in FIGS. 1 to 3, in the product region Pa, the plurality of wiring boards p arranged vertically and horizontally apart from each other have cavities 10 that open on the surface 2 and have a rectangular shape in plan view, A conductor frame (conductor portion) 8 for sealing is formed individually along the surface 2 of the ceramic layer s1 surrounding the cavity 10 in a rectangular shape in plan view. The conductor frames 8 and 8 of the wiring boards p and p adjacent to each other on the left and right are connected to each other through a connection line 9, and the conductor frame 8 for each wiring board p located along the outermost side of the product area Pa The left and right plating tie bars 15 are individually connected via 9i.
In each wiring board p, a pair of connection terminals 11 are formed on the surface of the lowermost ceramic layer s3 exposed on the bottom surface of the cavity 10, and the connection terminals 11 are formed on the ceramic layer s3 as shown in FIG. The pair of backside conductors 12 formed on the backside 3 of the first and second backside conductors 12 and the through-hole conductors 13 penetrating the ceramic layer s3 can be individually conducted. Further, the pair of back conductors 12 for each wiring board p can be individually conducted to the conductor frame 8 on the front surface 2 side through through-hole conductors td penetrating the ceramic layers s1 to s3.

That is, as shown in FIGS. 1 to 3, the plating electrodes 6 located on the left and right ear edges 5 in the ear portion 5 are connected via the connection line 14, the plating tie bar 15, the connection wiring 9 i, and the connection line 9. The conductor frame 8 can be electrically connected to each wiring board p. In each wiring board p, the conductor frame 8 and the pair of connection terminals 11 are individually connected via the two types of long and short through-hole conductors td and 13. It is possible.
2 and 3, the planned cutting plane cf is shown along the outer sides of the four sides of the conductor frame 8 for each wiring board p in plan view.
Further, the conductor frame 8, the connecting wire 9, the connecting wire 9i, the connecting terminal 11, the plating tie bar 15, the connecting tie bar 18, the back conductor 12, and the through-hole conductors 13 and td are mainly made of, for example, W or Mo. .
Furthermore, the plating tie bar 15 is printed with a conductive paste containing W powder or the like a plurality of times following the cross-sectional shape on the surface of the green sheet to be the ceramic layer s1, and then laminated and fired by a conventional method. By doing so, it is easily formed.
In addition, in the wiring board p after being separated into pieces along the planned cutting plane cf, the conductor frame 8 is used for brazing with a metal lid plate that closes the opening of the cavity 10 and a pair It also serves as a ground in the circuit including the connection terminal 11.

  According to the multi-piece wiring board 1a as described above, the thickness of the pair of plating tie bars 15 formed to face the pair of left and right ear sides (ear portions) 5 on the surface 2 of the ceramic layer s1 is the above-mentioned pair. From a position 16 close to the plating electrode 6 toward a position 17 away from the plating electrode 6, the taper shape (gradually) increases to 15t. As a result, between the wiring board p on the outer peripheral side of the product area Pa located relatively close to the plating electrode 6 and the wiring board p located on the center side of the product area Pa relatively far from the plating electrode 6. Also, the difference in conduction resistance due to the length of the conduction path is suppressed. Therefore, the plating current flows relatively uniformly to the wiring board p at any position in the product area Pa through the plating electrode 6, the plating tie bar 15, the connection wiring 9i, and the connection line 9. A multi-piece wiring board 1a is obtained in which the surface of the conductor frame 8, the connection terminal 11, and the back conductor 12 for each wiring board p is coated with a Ni plating film or an Au plating film with an approximate thickness.

As shown in FIG. 5, the plating tie bar 15 is connected to the central portion of the plating electrode 6 via the connection line 14 and from the position 16 close to the plating electrode 6, from the plating electrode 6. The thickness is increased stepwise (stepwise) 15 s toward the farthest position 17, and between the adjacent plating electrodes 6, 6, the position 17 is the furthest away from each plating electrode 6. It is also possible to adopt a form that is thickened like a staircase.
Further, as shown in FIG. 6, the plating tie bar 15 is connected to the central portion of the plating electrode 6 and from a position 16 close to the plating electrode 6 to a position 17 farthest from the plating electrode 6. The thickness is gradually increased outward in a curved shape (gradually) 15r, and between adjacent plating electrodes 6 and 6, the thickness is increased in a curved shape 15r toward a position 17 farthest from each plating electrode 6. It is good also as a form.
Furthermore, as shown in FIG. 7, the thickness is increased from a position 16 connected to the central portion of the plating electrode 6 and close to the plating electrode 6 toward a position 17 farthest from the plating electrode 6. Thickened in a taper shape (gradually) 15t in the direction, and between adjacent plating electrodes 6 and 6, the plating is thickened in a taper shape 15t toward a position 17 farthest from the vicinity of each plating electrode 6 The tie bar 15c may be used.

Further, as shown in FIG. 8, the thickness is inward from a position 16 connected to the central portion of the plating electrode 6 and close to the plating electrode 6 toward a position 17 farthest from the plating electrode 6. Thickened stepwise (stepwise) in the direction of 15 s, and between adjacent plating electrodes 6 and 6, the plating is thickened in a stepped manner toward the position 17 farthest from the vicinity of each plating electrode 6. The tie bar 15c may be used.
In addition, as shown in FIG. 9, the thickness increases from a position 16 connected to the central portion of the plating electrode 6 and close to the plating electrode 6 toward a position 17 farthest from the plating electrode 6. Thicken inwardly in a curved shape (gradually) 15r, and between plating electrodes 6 and 6 adjacent to each other, the thickness of the curved shape 15r increases toward the position 17 farthest from each plating electrode 6 The tie bar 15c may be used.
As shown in FIGS. 6 to 9 described above, the plating thickness changes gradually or stepwise from the position 16 close to the plating electrode 6 toward the position 17 farthest from the plating electrode 6. Even if the tie bars 15 and 15c are used, it is possible to constitute a multi-cavity wiring board having the same effects as the multi-cavity wiring board 1a.

FIG. 10 is a partial plan view showing a multi-piece wiring board 1b as an application form of the wiring board 1a, and FIG. 11 is a vertical sectional view taken along the line ZZ in FIG.
As shown in FIG. 10, the multi-piece wiring board 1b includes the same product region Pa in which a plurality of wiring boards p having the conductor frame 8, the connection terminals 11, the cavities 10, and the like are arranged vertically and horizontally, and the outside thereof. And the same ear portion 5 as described above.
The multi-piece wiring board 1b is different from the wiring board 1a in that the surface 2 of the upper and lower ear edges 5 is farthest from the left and right plating electrodes 6 in the plating tie bar 15 as shown in FIG. A connection (plating) tie bar 20 having a thinnest thickness at a position 22 adjacent to the position 17 and a taper (gradually) thickness 23 toward the central portion 21 of each ear edge 5 is formed. It is formed.
Furthermore, along the vertical direction of FIG. 10, the connection wiring 9j connecting between the connection tie bar 20 and the conductor frame 20 of each wiring board p located on the outermost side in the product area Pa, and the vertical direction Another difference from the wiring board 1a is that a connection line 9f for connecting the conductor frames 8 and 8 for each adjacent wiring board p is additionally formed.

According to the multi-piece wiring board 1b as described above, the pair of left and right plating tie bars 15 can provide the same effect as the wiring board 1a, and the pair of upper and lower connection tie bars 20 extends along the vertical direction. The connection wiring 9j and the connection line 9f are further provided, so that the difference in distance from each plating electrode 6 also in the conduction path along the conductor frame 8 of the plurality of wiring boards p on the surface 2 along the vertical direction. Can be reduced or suppressed evenly at any position in the product area Pa. Accordingly, the plating current supplied to each plating electrode 6 flows relatively uniformly to the wiring board p at any position in the product area Pa. Therefore, the plating current is applied to the surface of the conductor frame 8 or the like for each wiring board p. A multi-piece wiring board 1b in which a Ni plating film and an Au plating film are coated with a more uniform thickness can be obtained.
Incidentally, the tie bar 20 for connection (plating) of the multi-piece wiring board 1b has a form in which the thickness changes stepwise (stepwise) 25 as shown in FIG. 12, or the thickness changes in a curved shape. It is good also as a form. Further, the connecting tie bar 20 may have a shape that becomes thicker in a tapered shape 23, a stepped shape 25, or a curved shape toward the inside of the ceramic layer s1.

FIG. 13 is a vertical sectional view showing a multi-piece wiring board 1c in a form different from the wiring boards 1a and 1b, and FIG. 14 is a partial plan view taken along the line U-U in FIG. 15 is a schematic vertical sectional view taken along line VV in FIG.
As shown in FIGS. 13 and 14, the multi-piece wiring board 1c has a front surface 2 and a back surface 3 and is formed by laminating two upper and lower ceramic layers (insulating layers) s1 and s2 in the thickness direction. A product region Pa in which a plurality of wiring boards p exhibiting a rectangle (rectangle) in a plan view along the vertical direction and the ceramic layers s1 and s2 as described above are stacked, and is formed on the outer periphery of the product region Pa. And a pair of (a plurality of) plating electrodes 6 formed on the outer surface 4 of the pair of left and right ear edges 5 in FIG. 13. , Including.

The ceramic layers s1 and s2 are also mainly composed of alumina.
14 indicates a virtual planned cutting plane cf that surrounds the outer edges of the individual wiring boards p while adjoining each other and separates the product region Pa and the ear portion 5.
As shown in FIGS. 13 and 14, the surface 2 of the product region Pa is adjacent to the surface conductor 26 straddling each corner of the four wiring boards p adjacent vertically and horizontally and along the outermost side of the product region Pa. A surface conductor 26 and the like straddling the corners of the two wiring boards p are formed. That is, four pads are individually formed at the four corners of the surface 2 of each obtained wiring board p when separated along the planned cutting plane cf.

As shown in FIG. 14, among the ear portions 5 between the ceramic layers s1 and s2, a pair of left and right long edges 5 are formed with plating tie bars 35 facing each other, and a pair of upper and lower short edges are formed. A connection tie bar 39 is formed on the ear side 5. As shown in FIG. 15, the plating tie bar 35 is directly connected to the central portion of the plating electrode 6 and located at a position 37 farthest from the plating electrode 6 from a position 36 closest to the plating electrode 6. The thickness is formed in a tapered shape (gradually) 38 toward the top. Also between the plating electrodes 6 and 6 adjacent to each other at the right and left ear edges 5, the thickness is gradually increased (gradually) 38 toward a position 37 farthest from each plating electrode 6. It should be noted that the thickness of the plating tie bar 35 may be changed in a curved shape (gradually) or stepped (stepped) between the positions 36 and 37.
On the other hand, the upper and lower connecting tie bars 39 that connect the upper and lower positions 37, 37 of the left and right plating tie bars 35 have the same width and thickness, or, as described above, only the thickness gradually or It is changing in stages.

As shown in FIGS. 13 and 14, between the ceramic layers s1 and s2, outer corners of a plurality of wiring boards p arranged along the inner peripheral side of the ear portion 5 and the outermost side of the product region Pa, or The wiring portion (conductor portion) 30 formed across the corners of the four adjacent wiring boards p in the product region Pa is substantially square in plan view, and the wiring portions 30 and 30 are connected horizontally. The connecting wiring 32 having a crank shape in plan view and the connecting wiring 34 for connecting the outer peripheral wiring portion 30 and the plating tie bar 35 are formed.
A through hole h penetrating the ceramic layers s1 and s2 in the thickness direction is located at the center of each wiring part 30. A substantially cylindrical through hole conductor 29 is formed along the inner wall surface of the through hole h. Is formed. Each wiring portion 30 and the surface conductor 26 can be electrically connected to each other through the through-hole conductor 29. As shown in FIG. 13, on the back surface 3 on the ceramic layer s2 side, a plurality of back surface conductors 28 similar to the surface conductors 26 are formed at the four corners for each wiring board p, and through the through-hole conductors 29, Each wiring part 30 and the surface conductor 26 can be individually conducted.

In other words, between the ceramic layers s1 and s2 for each wiring board p when separated into pieces along the scheduled cutting plane cf, four electrically independent wiring portions are arranged near the four corners. The portion is electrically connected to the pad on the front surface 2 side and the back surface conductor (connection terminal) on the back surface 3 side through the recessed groove conductors exposed on the outer surfaces of the four corners of each wiring board p.
The plating electrode 6, the wiring portion 30, the connection wiring 32, the connection wiring 34, the front surface conductor 26, the plating tie bar 35, the connection tie bar 39, the back surface conductor 28, and the through-hole conductor 29 are, for example, mainly W or It consists of Mo.
Further, the plating tie bar 35 is printed with a conductive paste containing W powder or the like on the surface of the green sheet to be the ceramic layer s2 later, and then laminated and fired by a conventional method. It is easily formed.

  According to the multi-piece wiring board 1c as described above, the thickness of the pair of plating tie bars 35 formed facing the pair of left and right ear sides 5 in the ear portion 5 between the ceramic layers s1 and s2 is as described above. From a position 36 adjacent to the pair of plating electrodes 6 to a position 37 farthest from the plating electrode 6, the thickness increases gradually (stepwise) 38 or stepwise. As a result, between the wiring board p on the outer peripheral side of the product area Pa located relatively close to the plating electrode 6 and the wiring board p located on the center side of the product area Pa relatively far from the plating electrode 6. The difference in conduction resistance due to the length of the conduction path is also reduced. Accordingly, the plating current through the plating electrode 6, the plating tie bar 35, the connection wiring 34, and the connection wiring 32 flows relatively uniformly to the wiring board p at any position in the product area Pa. The front and back conductors 26 and 28 for each wiring board p are formed as a multi-piece wiring board 1c in which the surfaces of the front and back conductors 26 and 28 are coated with a Ni plating film or an Au plating film with an approximate thickness.

The present invention is not limited to the embodiments described above.
For example, the insulating layer may be made of a high-temperature fired ceramic other than alumina, or a glass-ceramic that is a kind of low-temperature fired ceramic, or a resin such as epoxy. Among these, when glass-ceramic or epoxy resin is used, the conductors such as the electrode 6 for plating, the conductor frame 8, the tie bars 15 and 35 for plating, and the wiring portion 30 are Cu, Ag, Cu alloy, or Ag alloy. Applies.
Further, only one electrode 6 for plating may be provided on the same ear edge 5 of the ear portion 5, or three or more may be provided side by side.
Furthermore, one or more of the plating electrodes 6 may be formed in the same number or different numbers for each of the four sides 5 of the ear 5. In this embodiment, the plating tie bars 15 and 35 are disposed for each of the four ear sides 5 constituting the ear portion 5.
The plating tie bar 35 may be disposed on the front surface or the back surface of the uppermost ceramic layer among a plurality of ceramic layers (insulating layers), and the plating tie bar 15 includes a plurality of ceramic layers (insulating layers). Between the layers).

Further, the “gradual” includes a form in which the thickness becomes curved (curved) from a position close to the plating electrode toward a position away from the plating electrode.
In addition, the “stepwise” includes a mode in which the thickness gradually increases stepwise through a plurality of inclined sides from a position close to the plating electrode to a position away from the plating electrode. .
Furthermore, in the multi-cavity wiring boards 1a to 1c, in the form in which a virtual cutting planned surface cf indicated by a broken line is arranged at the boundary between the product region Pa and the ear portion 5 and the boundary between the wiring boards p and p, this is required. Each wiring board p is separated into pieces by carrying out a sinter (shearing) process along the scheduled cutting surface cf.
In addition, in the multi-piece wiring boards 1a to 1c, instead of the planned cutting plane cf, a substantially V-shaped dividing groove opened on the front surface 2 is formed, or both the front surface 2 and the back surface 3 are cross-sectioned. A pair of substantially V-shaped dividing grooves may be formed symmetrically, and each wiring board p may be separated into pieces by bending along the dividing grooves.

  It has both a product area in which a plurality of wiring boards are arranged vertically and horizontally and an ear part on which an electrode for plating is formed on the outer surface, and the wiring board at any position in the product area is covered with the conductor portion. In addition, it is possible to reliably provide a multi-piece wiring board having a uniform metal plating film thickness.

1a to 1c ……………… Manufacturing circuit board 5 ………………………… Ear part / ear side 6 ………………………… Plating electrode 8 …………… …………… Conductor frame (conductor part)
9j, 34 ……………… Connection wiring 15, 15c, 35 …… Plating tie bar 16, 36 ………… Position close to the plating electrode 17, 37 ……………… From the plating electrode Distant position 30 ………………………… Wiring part (conductor part)
Pa …………………… Product area p ………………………… Wiring board s1 to s3 ……………… Ceramic layer (insulating layer)
15t, 15r, 23 ... tapered / curved (gradual)
15s, 25 ............... Stairs (stepwise)

Claims (3)

A product region in which a plurality of insulating layers are stacked, and a plurality of wiring boards that are rectangular in a plan view along the thickness direction are arranged along the length and breadth,
In the same manner as described above, an insulating layer is laminated, and an ear portion that is located along the outer periphery of the product region and has a rectangular frame shape in plan view;
A plating electrode formed on the outer surface of the ear,
A plating tie bar formed between the ears and electrically connected between the electrode for plating and the connection wires extending from the conductor portions of the plurality of wiring boards located on the outermost side in the product region;
The thickness of the plating tie bar is increased from a position close to the plating electrode toward a position away from the plating electrode.
A multi-piece wiring board characterized by that. The thickness of the plating tie bar is gradually increased from a position close to the plating electrode to a position away from the plating electrode, or is gradually increased.
The multi-piece wiring board according to claim 1, wherein: A plurality of the plating electrodes are formed on the outer surface of the ear portion, and the thickness of the plating tie bar connecting between two adjacent plating electrodes is the thinnest at a position close to each plating electrode. , And thickest at the position farthest from each plating electrode,
The multi-piece wiring board according to claim 1, wherein the multi-piece wiring board is provided.

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