JP2001077507A - Manufacture of castellation structure of multi-circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method which forms a plurality of castellation conductors each isolated and insulated on the inner peripheral surface of a through-hole of a multi-circuit board. SOLUTION: After a lamination process is completed, an I/O land 15 is printed on the upper surface of a multi-circuit board 11, simultaneously with printing of a castellation conductor 14 over the whole inner peripheral surface of a through-hole 13. After that, intersecting parts of a peripheral part of the through-hole 13 and a diving line 12, i.e., both edge portions in the longitudinal direction of the through-hole 13 are punched-out, the castellation conductor 14 is divided into two parts along the dividing line 12, and the castellation conductor 14 is insulated for each circuit board. I/O land 15 is divided into two parts along the dividing line 12, and the I/O land 15 is insulated for every circuit board. After that, the multi-circuit board 11, the castellation conductor 14 and the I/O land 15 are baked at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a castellation structure of a multi-piece substrate, which is an improved method of forming a castellation structure on the multi-piece board.

[0002]

2. Description of the Related Art Conventionally, when a ceramic circuit board is manufactured, a multi-piece board is formed by integrally forming a large number of circuit boards by a green sheet laminating method or the like. By dividing along the dividing line formed at the boundary of the circuit board, the circuit board is divided into individual circuit boards.

When a castellation (dent) for soldering is formed on the side surface of each circuit board by such a manufacturing method, as shown in FIG. To form the caster conductor 4 (see FIG. 8) by printing a conductive paste on the entire inner peripheral surface of the through hole 3 by a suction method. The output land 5 is printed. In this printing process, as shown in FIG.
The multi-piece substrate 1 is set on the suction plate 7, and a screen mask 8 is set on the multi-piece substrate 1, and an air suction force is applied from the suction holes 9 formed in the suction plate 7 into the through holes 3. Then, the conductor paste on the screen mask 8 is extruded by the squeegee 10 from the opening 8a of the screen mask into the through hole 3 to print the castellation conductor 4.

[0004] Multi-piece substrate 1 after printing and baking processes
Is divided into individual circuit boards A11, A12,... When divided along the division line 2. Thereby, the castellation conductor 4 on the inner peripheral surface of each through hole 3 is divided into two along the division line 2 and divided into the castellation conductors 4 of two adjacent circuit boards.

[0005] Such a circuit board with the castellation conductors 4 is surface-mounted on an external board (mother board), and the castellation conductors 4 are soldered to lands on the external board. In such a circuit board for surface mounting, the castellation structure is indispensable for improving soldering reliability and confirming soldering.

[0006]

By the way, in terms of quality control, it is necessary to measure and adjust (trimming, etc.) circuit characteristics such as the printed resistance value of each circuit board A11, A12,. This inspection / adjustment process is performed after the multi-piece board 1 is divided into individual circuit boards A11, A12,. This is because since the castellation conductors 4 of the two adjacent circuit boards are printed on the entire inner peripheral surface of the through hole 3 in the multi-piece board 1 before the division, the circuits of the two adjacent circuit boards are printed. This is because the short-circuit is caused by the castellation conductor 4. However, the multi-piece board 1 is divided into individual circuit boards A11,
When the inspection / adjustment process is performed after dividing into A12, ...
Each of the circuit boards A11, A12,... Has to be set one by one in an inspection jig for inspection, and there is a disadvantage that inspection efficiency and adjustment efficiency are extremely poor.

In most cases, components are mounted on the circuit boards A11, A12,... Before the multi-piece board 1 is divided in order to increase mounting efficiency. However, in the conventional castellation structure, the circuits on the two adjacent circuit boards are short-circuited by the castellation conductors 4, so that the electric inspection and adjustment before division are impossible, and the electric inspection and adjustment after division are impossible. Adjustment must be performed, and there is a disadvantage that the inspection efficiency and the adjustment efficiency are very poor.

In the related art, a short / open inspection of each circuit board may be performed on the multi-piece board 1 before division. When a short circuit occurs, one of two adjacent circuit boards is short-circuited. Since it is impossible to determine whether the circuit board is defective or not, the two adjacent circuit boards are both determined to be short-circuited. For this reason, even a non-defective product is determined as a defective product, and there is a disadvantage that the yield is reduced and the cost is increased.

In order to solve these disadvantages, as shown in FIG. 10, a strip-shaped dummy portion 6 (a portion to be finally discarded) is formed between the circuit boards A11, A12,.
It is conceivable that the castellation conductors (through holes 3) of the two circuit boards are completely separated and insulated by the dummy portion 6. However, in this configuration, since the strip-shaped dummy portions 6 are formed between the circuit boards, the number of circuit boards that can be obtained from one multi-piece board is reduced, and the production efficiency of the circuit boards is reduced. is there.

The present invention has been made in view of such circumstances, and accordingly, it is an object of the present invention to reduce the number of circuit boards having a castellation structure formed on a single multi-piece board without reducing the number of circuit boards. A multi-cavity board that can completely insulate circuits between circuit boards and that can measure and adjust circuit characteristics and perform a short / open inspection for each circuit board using a multi-cavity board before division To provide a method for manufacturing a castellation structure.

[0011]

In order to achieve the above object, a method for manufacturing a castellation structure for a multi-piece board according to the first aspect of the present invention is to divide the multi-piece board into individual circuit boards. The castellation conductor is printed on the entire inner peripheral surface of a large number of through holes formed along the dividing line, and then, by punching out the intersection of the peripheral portion of the through hole and the dividing line, The castellation conductor is divided along the division line.

In this method, the castellation conductor can be divided and insulated for each circuit board by punching, so that a strip-shaped dummy portion is not formed between the circuit boards.
The circuit of two adjacent circuit boards can be completely insulated, and the measurement and adjustment of circuit characteristics and short / open inspection can be accurately performed for each circuit board using a multi-cavity board before division. As a result, the inspection efficiency and the adjustment efficiency can be greatly improved, and the defective product can be completely specified, so that the yield can be improved. In addition, since a strip-shaped dummy portion is not formed between each circuit board, the number of circuit boards formed on one multi-piece board does not need to be reduced, and a large number of circuit boards can be efficiently used from one multi-piece board. Can be produced well.

In this case, the input and output lands of the castellation conductor are printed on the periphery of the through-hole simultaneously or separately with the printing of the castellation conductor, and then divided with the periphery of the through-hole. By punching out the intersection with the line, the input and output lands may be divided along the dividing line together with the castellation conductor. In this case, the input / output lands can be divided and insulated for each circuit board by punching.

When the multi-piece substrate is formed of a ceramic substrate, the multi-piece board is preferably fired simultaneously with the castellation conductor after punching. That is, in the case of a ceramic substrate, the punching process becomes impossible after the substrate is fired, but the punching process can be easily performed in the state of the raw substrate before firing.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIGS. First, multi-cavity board 1
1 will be described. The multi-piece substrate 11 is formed by a green sheet laminating method or the like, and has a large number of ceramic circuit boards A11, A12,..., Aij,. On the surface of the multi-piece board 11, the dividing lines 12 are formed along the boundaries of the circuit boards Aij.
(Scribe lines, snap lines, break grooves) are formed. A plurality of through holes 13 are formed in the multi-piece substrate 11 along the division lines 12. Each through hole 13 is used to form a castellation (dent) for soldering at, for example, four places on both side surfaces of each circuit board Aij.

In this case, the shape of the through-hole 13 is initially formed in a rectangular shape as shown in FIGS. 1 and 4 (a). A punch 21 (see FIG. 2) in which the intersection between the peripheral edge of the through hole 13 and the dividing line 12, that is, both longitudinal edges of the through hole 13 are circular or elliptical.
3), and the shape of the through hole 13 finally becomes an oval shape (oval) as shown in FIGS. 3 and 4 (b). However, the shape of the through-hole 13 is not limited to an oval shape, and may be any shape such as a square or an ellipse.

As shown in FIGS. 4 (b) and 5, on the inner peripheral surface of each through-hole 13, two castellation conductors 14 are opposed to each other with the divided line 12 interposed therebetween by a method described later. In addition, on one surface of the multi-piece substrate 11, input / output lands 15 of each castellation conductor 14 are separately formed so as to face each other with the division line 12 interposed therebetween. Finally, the castellation conductors 14 and the input / output lands 15 are
And fired simultaneously. The dimensional relationship of each part is, for example, that the major axis h of the through hole 13 is 500 to 1000 μm and the minor axis i is 3
It is set to 00 to 600 μm. The width j of the castellation conductor 14 after the punching step described later is set to 300 to 800 μm in order to secure a soldering area.

The multi-piece substrate 11 is 800-1000 ° C.
If it is formed of a low-temperature fired ceramic fired at
The conductor paste for printing the castellation conductor 14 and the input / output lands 15 is Ag / Pt, Ag / Pd, Ag,
A conductor paste of a low-melting-point metal having good electrical characteristics such as Cu may be used. In addition, the multi-piece substrate 11 has a temperature of 1600 ° C.
If it is made of alumina or the like that is fired before and after,
For simultaneous firing, it is necessary to use a conductor paste of a high melting point metal such as W or Mo.

Next, a method of manufacturing the multi-piece substrate 11 will be described. First, rectangular through holes 13 are punched and formed by a punching machine or the like on a plurality of green sheets used to form the multi-piece substrate 11, and the green sheets of each layer are laminated to form the multi-piece substrate 11. At this time, the layers are laminated so that the through holes 13 of the green sheets of the respective layers match. Alternatively, the multi-piece substrate 11
Alternatively, a rectangular through hole 13 may be punched and formed by post-processing. In short, the rectangular through hole 13 (see FIG. 1) may be formed along the division line 12 by any method.

After completion of the laminating step, as shown in FIG. 4A, the castellation conductors 14 are printed on the entire inner peripheral surface of the through hole 13 by a suction method, and at the same time, as shown in FIG. The input / output lands 15 are printed on the upper surface of the substrate 11. In this printing process, since the castellation conductors 14 (input / output lands 15) of the adjacent circuit board Aij are continuously printed, the circuits of the adjacent circuit boards Aij are short-circuited by the castellation conductors 14 (input / output lands 15). It is in a state where it has been done. The castellation conductors 14 and the input / output lands 15 may be printed separately (the printing order does not matter).

After completion of the printing process, in the state of the raw substrate before baking the multi-piece substrate 11, as shown in FIG. 2, the intersection between the periphery of the rectangular through hole 13 and the dividing line 12, that is, the through Both edges in the longitudinal direction of the hole 13 are punched with a circular or elliptical punch 21 to make the shape of the through hole 13 oval. As a result, as shown in FIGS. 3 and 4B, the castellation conductor 14 is divided into two along the division line 12 to insulate the castellation conductor 14 for each circuit board Aij and to provide the input / output lands 15 Is divided into two along the division line 12 to insulate the input / output lands 15 for each circuit board Aij. After the punching step, the multi-piece substrate 11 is simultaneously fired with the castellation conductors 14 and the input / output lands 15.

In the multi-piece substrate 11 manufactured as described above, the castellation conductors 14 (input / output lands 15) are divided into two parts by the punching process with the division line 12 interposed therebetween and are insulated from each other. Even before the multi-piece board 11 is divided by the dividing lines 12, the circuits of the individual circuit boards Aij are completely insulated. Therefore, before the multi-piece board 11 is divided by the dividing line 12, the multi-piece board 11 is set on an inspection jig to measure and adjust the circuit characteristics such as the printed resistance value of the individual circuit boards Aij and to short-circuit. The open inspection can be performed accurately, and the electrical inspection and adjustment can be performed before the division by mounting components on each circuit board Aij before dividing the multi-piece board 11. As a result, the measurement efficiency and the inspection efficiency can be greatly improved as compared with the conventional case where the circuit boards are set one by one on the inspection jig after the division and the measurement and inspection are performed. Moreover, since the circuits of the individual circuit boards Aij are completely insulated, defective products can be completely specified when a short circuit occurs, and it is not possible to distinguish between good and defective products between adjacent circuit boards. Compared with the related art, the number of defective products can be reduced to 従 来 or less, the yield can be improved, and the production cost can be reduced accordingly.

Further, since it is not necessary to form a strip-shaped dummy portion between the circuit boards Aij, the multi-piece board 11 has
A large number of circuit boards Aij can be efficiently produced from one multi-piece board 11 without reducing the number of circuit boards Aij formed on the multi-piece board 11.

The circuit board Aij obtained by dividing the multi-piece board 11 by the dividing lines 12 is surface-mounted on an external board, and the castellation conductors 14 are soldered to lands on the external board.

The shape of the punch 21 used in the punching step is not limited to a circle or an ellipse, but may be a square or the like. In other words, the shape is such that the castellation conductor 14 and the input / output land 15 can be divided and insulated. good.

Further, through holes may be formed at positions corresponding to the corners of each circuit board Aij. In this case, since the two divided lines pass through the through hole at a right angle, the castellation conductor printed on the entire inner peripheral surface of the through hole is punched so as to be divided into four, and the castellation conductor is provided for each circuit board. May be divided and insulated. In addition, the present invention can be implemented with various changes such as changing the number of through holes per circuit board.

[0027]

As is apparent from the above description, according to the first aspect of the present invention, after the castellation conductor is printed on the entire inner peripheral surface of the through-hole, the peripheral portion of the through-hole and the dividing line are formed. Since the castellation conductor is divided along the division line by punching out the intersection, the castellation conductor can be divided and insulated for each circuit board by punching. This makes it possible to completely insulate circuits between the circuit boards without reducing the number of circuit boards with a castellation structure formed on one multi-piece board, and to remove the multi-piece board before division. It can be used to measure and adjust circuit characteristics and perform short / open inspection for each circuit board.

According to a second aspect of the present invention, the input and output lands of the castellation conductor are printed on the periphery of the through hole.
By punching out the intersection between the periphery of the through hole and the dividing line, the input and output lands are divided along the dividing lines together with the castellation conductors. Can be formed, and the reliability of soldering can be improved by the input / output lands.

According to the third aspect of the present invention, the multi-piece substrate is formed of a ceramic substrate, and the blanking process is performed in a state of a raw substrate before firing. It can be carried out.

[Brief description of the drawings]

FIG. 1 is a partial plan view of a multi-piece substrate illustrating a printing process according to an embodiment of the present invention.

FIG. 2 is a partial plan view of a multi-piece substrate illustrating a punching step.

FIG. 3 is a partial plan view of the multi-piece substrate showing a state after a punching step is completed.

FIG. 4A is an enlarged cross-sectional view of a portion around a through-hole before a punching process, and FIG. 4B is an enlarged cross-sectional view of a portion around a through-hole after a punching process is completed.

FIG. 5 is an enlarged perspective view of a castellation peripheral portion of the circuit board.

FIG. 6 is a plan view of the whole multi-piece substrate.

FIG. 7 is a partial plan view of a conventional multi-piece substrate.

FIG. 8 is an enlarged perspective view of a portion around a castellation of a conventional circuit board.

FIG. 9 is an enlarged vertical sectional view illustrating a conventional method for printing castellated conductors.

FIG. 10 is a partial plan view of a conventional improved multi-cavity substrate.

[Explanation of symbols]

11: Multi-cavity board, 12: Split line, 13: Through hole, 14: Castellation conductor, 15: Input / output land, 21: Punch, Aij: Circuit board.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5E317 AA04 AA22 AA25 AA28 BB04 BB12 BB14 BB16 BB17 BB18 CC22 CC23 CD21 CD29 CD32 GG17 5E338 AA02 BB13 BB17 BB25 BB42 BB45 BB46 CD15 CD24 EE32

Claims (3)

[Claims] 1. A castellation conductor is printed on the entire inner peripheral surface of a large number of through holes formed along a dividing line for dividing a multi-cavity substrate into individual circuit boards. A method of manufacturing a castellation structure for a multi-piece substrate, wherein the castellation conductor is divided along the division line by punching out the intersection between the peripheral edge of the substrate and the division line. 2. An input / output land of the castellation conductor is printed on the periphery of the through-hole simultaneously or separately with the printing of the castellation conductor. 2. The method according to claim 1, wherein the input and output lands are divided along with the dividing lines along with the dividing line by punching an intersection. 3. The multi-piece substrate is formed of a ceramic substrate, and after performing the punching, the multi-piece substrate is simultaneously fired with the castellation conductor. A method for manufacturing the castellation structure of a multi-cavity substrate as described above.