JP2000012990A - Work board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work board, which enables a board to be prevented from warping and electronic parts to be precisely, readily mounted on a product portion to be a printed wiring board. SOLUTION: A work board 1 has a wiring pattern 3 and a product portion 4 to be a printed wiring board by pelletizing. A metal frame layer 5 is formed outside the product portion 4 on the periphery of the work board 1, and a thickness F of the metal frame layer 5 is larger than a thickness P of the wiring pattern 3 which is provided at the product portion 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a work board for forming a printed wiring board.

[0002]

2. Description of the Related Art Conventionally, a printed wiring board is manufactured by mounting electronic components and the like on a work board and then separating the electronic components and the like. The work board before mounting the electronic components is shown below.
As shown in FIGS. 8 to 11, the work substrate 9 has a wiring pattern 3 and a product section 4 to be formed into a printed wiring board by singulation. This product part 4
Is formed on the inner peripheral portion of the work substrate 9, for example, in three pieces. Each product part 4 includes an insulating substrate 2 made of polyimide or the like and a plurality of wiring patterns 3 provided on the surface of the insulating substrate 2. Have.

[0003]

However, the conventional work board has the following problems. That is, if thermal stress or the like acts on the insulating substrate 2 due to a difference in the coefficient of linear expansion between the insulating substrate 2 and the wiring pattern 3, the work substrate 9 may be warped (FIGS. 8 and 9). . Therefore, the electronic components 6 (FIG.
), It becomes difficult to read the alignment, and it may be difficult to mount the electronic component at an accurate position. In particular, as the thickness of the printed wiring board is reduced, the thickness T of the product portion 4 of the work substrate 9 is set to 200 μm.
If the thickness is less than m, warpage is likely to occur, and the above problem is likely to occur.

In order to solve this problem, through holes 95 (FIGS. 8 and 9) are provided at four corners of the outer peripheral portion of the work substrate 9 outside the product portion 4, and a jig for preventing warpage (see FIGS. (Abbreviation) may be inserted and pressed to eliminate the warpage. However, in this case, the warpage prevention jig is required. In addition, it takes time to mount the electronic components by inserting the warp prevention jig into the through hole 95.

If the thickness T of the product portion 4 of the work substrate 9 is reduced to, for example, 75 μm, which is 200 μm or less, for example, when the work substrate 9 having a length of 25 mm is in a cantilever state, FIG. As shown, the amount of droop H increases to about 12 mm due to its own weight. Therefore, when the transfer of the work substrate 9 is performed by the rollers 81 and 82, the work substrate 9 may not reach the next roller 82 from the preceding roller 81, and a transfer failure of the work substrate 9 may occur.

In order to solve this, as shown in FIG. 11, a metal backup 71 is attached to the outer peripheral surface of the work board 9 outside the product section 4 so as to surround the entire periphery. Alternatively, a clip-shaped backup 72 may be attached to the outer peripheral edge of the work substrate 9 along the substrate flow direction. However, in this case, the backups 71 and 72 are
Is required separately from In addition, it takes time to mount these components.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and it is an object of the present invention to prevent a board from warping and to mount an electronic component accurately and easily on a product portion to be a printed wiring board. It is intended to provide a work substrate that can be used.

[0008]

According to a first aspect of the present invention, there is provided a work board provided with a product portion to be a printed wiring board.
A metal frame layer is formed on an outer peripheral portion of the work substrate outside the product portion, and a thickness of the metal frame layer is larger than a thickness of a wiring pattern provided on the product portion. The feature is the work board.

What is most notable in the present invention is that the metal frame layer is formed on the outer periphery of the work substrate, and the thickness of the metal frame layer is larger than the thickness of the wiring pattern.

Next, the operation of the present invention will be described. In the work board of the present invention, a metal frame layer thicker than the wiring pattern is formed on the outer periphery of the work board, outside the product section. for that reason,
Since the rigidity can be ensured by the metal frame layer, even if a thermal stress or the like acts on the work board due to a difference in linear expansion coefficient, it is possible to prevent the work board from being warped. Therefore, when mounting the electronic component on the product part of the work board, it is easy to read the alignment, and the electronic component can be easily mounted at an accurate position. Further, the warpage prevention jig shown in the conventional example is not required, and the electronic components can be efficiently mounted.

Further, since the rigidity can be secured by the metal frame layer, the amount of droop of the work substrate due to its own weight can be reduced. Therefore, when the work substrate is transported by a roller, the work substrate can reliably reach the next roller from the preceding roller, and the transport failure of the work substrate can be prevented.

Preferably, the thickness of the work board excluding the wiring pattern is 30 to 100 μm. In this case, the effect of preventing warpage by providing the metal frame layer can be exhibited most effectively.

Next, it is preferable that the metal frame layer has a thickness of 25 to 100 μm. In this case, the rigidity of the metal frame layer can be sufficiently ensured. If the thickness of the metal frame layer is less than 25 μm, the rigidity of the metal frame layer may be insufficient. On the other hand, if the thickness of the metal frame layer exceeds 100 μm, problems such as an increase in the cost of the material itself and an increase in the cost when forming the metal frame layer may occur.

Next, the difference between the thickness of the metal frame layer and the thickness of the wiring pattern is preferably 15 to 90 μm. In this case, the rigidity of the metal frame layer can be sufficiently ensured. If the difference between the thickness of the metal frame layer and the thickness of the wiring pattern is less than 15 μm, the rigidity of the metal frame layer may be insufficient. On the other hand, if the difference between the thickness of the metal frame layer and the thickness of the wiring pattern exceeds 90 μm, a problem such as an increase in cost when forming the metal frame layer may occur.

For example, as in the invention described in claim 4,
The metal frame layer may be formed on one side of the work board, and the metal frame layer may be formed on both sides of the work board. There is also.

Next, it is preferable that the metal frame layer is formed so as to surround the entire periphery of the outer peripheral portion of the work substrate. Claim 7
As described above, the metal frame layer is preferably provided in a strip shape along the board flow direction when the work board is mounted. In these cases, when the work substrate is transported by a roller, the work substrate can be more reliably delivered from the preceding roller to the next roller, and the transport failure of the work substrate is reliably prevented. can do.

Next, it is preferable that the metal frame layer comprises a metal foil and a metal plating film. In this case, after forming the metal foil having substantially the same thickness as the wiring pattern together with the wiring pattern, the surface of the metal foil is plated to form the metal plating film, thereby forming the metal frame layer. can do. Therefore, the thickness of the metal frame layer can be surely made larger than the thickness of the wiring pattern by the amount of the metal plating film.

The metal plating film is made of, for example, Cu,
It is preferable that at least one of Ni, Au, and Ag is used. Further, the metal frame layer can be easily formed integrally with the work substrate by etching and plating (see Embodiment 1). For this reason, it is not necessary to mount a backup as shown in the conventional example, and electronic components can be mounted efficiently.

Further, the metal frame layer can be formed only of a metal foil. In this case, a work board is prepared in which the thickness of the metal foil is different on one side and the other side, and the wiring pattern is formed from the thinner metal foil by subjecting the work board to, for example, etching. And
The metal frame layer can be formed from a thicker metal foil. Therefore, the thickness of the metal frame layer can be reliably made larger than the thickness of the wiring pattern by the difference between the thickness of the metal foil on one side and the thickness of the metal foil on the other side of the work substrate.

Further, the metal frame layer can be easily formed integrally with the work substrate by, for example, etching or the like (see Embodiment 4). For this reason, it is not necessary to mount a backup as shown in the conventional example, and electronic components can be mounted efficiently.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 shows a work board according to an embodiment of the present invention.
This will be described with reference to FIG. The work substrate 1 of this example is shown in FIG.
As shown in FIG. 4, a product part 4 having a wiring pattern 3 and being formed into a printed wiring board by singulation is provided. On the outer peripheral portion of the work substrate 1, the product portion 4
The metal frame layer 5 is formed on the outer side, and the thickness F of the metal frame layer 5 is larger than the thickness P of the wiring pattern 3 provided on the product part 4. The metal frame layer 5 is formed on one side of the work substrate 1 so as to surround the entire periphery of the outer peripheral portion. The metal frame layer 5 is made of a copper foil 53 as a metal foil.
And a metal plating film 55. In addition, the above product section 4
Are formed, for example, in three pieces on the inner peripheral portion of the work substrate 1, and each product part 4 has an insulating substrate 2 and a plurality of wiring patterns 3 provided on the surface of the insulating substrate 2.

Next, a description will be given according to the method of manufacturing the work substrate 1. First, an inner peripheral portion on the insulating substrate 2 is etched by performing etching or the like on a copper-clad laminate having a copper foil adhered to one side of an insulating substrate made of glass polyimide, glass epoxy, glass bismaleimide triazine, or the like. Next, a plurality of wiring patterns 3 are formed. At the same time, a copper foil 53 as the metal foil is formed on the outer peripheral portion of the insulating substrate 2 so as to surround the entire periphery. Then,
A plating process is performed on the surface of the copper foil 53 so that Cu, N
A metal plating film 55 made of i, Au, Ag or the like is formed. Thus, the work substrate 1 provided with the metal frame layer 5 is formed.

The thickness F of the metal frame layer 5 is 53 μm.
It is. The thickness M of the copper foil 53 forming this is 18
μm, and the thickness G of the metal plating film 55 is 35 μm. Also, the thickness P of the wiring pattern 3 is
Is substantially equal to the thickness M. That is, the thickness F of the metal frame layer 5 is 35 μm, which is the thickness G of the metal plating film 55.
Only, it is larger than the thickness P of the wiring pattern 3. The width L of the metal frame layer 5 is 5 mm. The thickness T of the product part 4 is 75 μm, and it is thin. The thickness of the work substrate 1 excluding the wiring pattern 3 is 57 μm.

Then, the work board 1 is transported to an electronic component mounting device (not shown), and the electronic components 6 are mounted on the respective product parts 4 of the work board 1. FIG. 4 shows the work board 1 on which the electronic components 6 are mounted.
Reference numeral 46 in FIG. 4 denotes an electronic component mounting unit. And
Each product part 4 of the work board 1 is singulated to manufacture a printed wiring board.

Next, the operation of this embodiment will be described. In the work board 1 of this example, a metal frame layer 5 thicker than the wiring pattern 3 is formed on the outer periphery of the work board 1 outside the product section 4. Therefore, the rigidity can be ensured by the metal frame layer 5. Therefore, even if a thermal stress or the like acts on the insulating substrate 2 due to a difference in a linear expansion coefficient between the insulating substrate 2 and the wiring pattern 3, the work substrate 1 is not affected. Warpage can be prevented from occurring.

Therefore, when mounting the electronic components on the product section 4 of the work board 1, it is easy to read the alignment, and the electronic components can be easily mounted at accurate positions. Also, the warpage prevention jig (not shown) shown in the conventional example is not required, and the mounting of the electronic component can be performed efficiently.

Further, since the rigidity can be ensured by the metal frame layer 5, even if the work board 1 having a length of 25 mm is in a cantilever state, for example, as shown in FIG. H can be reduced to about 3 mm. Therefore, when the transfer of the work substrate 1 is performed by the rollers 81 and 82, the work substrate 1 can reliably reach from the preceding roller 81 to the next roller 82, and the transfer failure of the work substrate 1 is prevented. be able to.

The thickness T of the product part 4 is as thin as 75 μm, and the thickness of the work substrate 1 excluding the wiring pattern 3 is 57 μm. Therefore, the effect of preventing warpage by providing the metal frame layer 5 can be most effectively exerted.

The thickness F of the metal frame layer 5 is 5
The difference between the thickness F of the metal frame layer 5 and the thickness P of the wiring pattern 3 is 35 μm. Thereby, the rigidity of the metal frame layer 5 can be sufficiently ensured.

The metal frame layer 5 is formed so as to surround the entire periphery of the outer periphery of the work substrate 1 (FIG. 2). Thus, when the work substrate 1 is transported by the rollers as described above, the work substrate 1 is moved along the substrate flow direction D as shown in FIG.
The work can be more reliably delivered from the front roller 81 to the next roller 82, and the transfer failure of the work substrate 1 can be reliably prevented.

As described above, the metal frame layer 5 is formed by forming a copper foil 53 having the same thickness as the wiring pattern 3 and then forming a metal plating film 55 on the surface of the copper foil 53. It is formed from a copper foil 53 as a foil and a metal plating film 55. Therefore, the thickness F of the metal frame layer 5 can be surely made larger than the thickness P of the wiring pattern 3 by the thickness G of the metal plating film 55.

As described above, the metal frame layer 5 can be easily formed integrally with the work substrate 1 by etching and plating. Therefore, it is not necessary to attach the backups 71 and 72 shown in the conventional example, and it is possible to efficiently mount electronic components.

Embodiment 2 As shown in FIG. 5, the work board 12 of this embodiment has the metal frame layer 5 formed on both sides of the work board 12. On one side of the work substrate 12, the thickness Fs of the metal frame layer 5 is larger than the thickness Ps of the wiring pattern 3. Also on the other surface side, the thickness Fb of the metal frame layer 5 is larger than the thickness Pb of the wiring pattern 3. The thickness T of the product part 4 is 18
0 μm and thin. Other configurations are the same as those of the first embodiment. This embodiment also has the same operation and effect as the first embodiment. When the metal frame layer 5 is formed on both sides of the work board 12, the work board 1
Preferably, the thickness W of the outer peripheral portion of No. 2 is 250 μm or less.

Embodiment 3 In the work board 13 of this embodiment, as shown in FIG. 6, the metal frame layer 5 is provided in a strip shape along the board flow direction D when the work board 12 is mounted (see FIG. 3). Things. Other configurations are the same as those of the first embodiment. This embodiment also has the same operation and effect as the first embodiment.

Embodiment 4 As shown in FIG. 7, the work board 14 of this embodiment is such that the metal frame layer 54 is formed only of a copper foil 534 as a metal foil. In the work substrate 14, the wiring pattern 3 is formed on one side, and the metal frame 54 is formed on the other side. Other configurations are the same as those of the first embodiment.

Hereinafter, a method of manufacturing the work substrate 14 will be described. First, a copper-clad laminate with copper foil stuck on both sides of an insulating substrate is subjected to half-etching only on one side to prepare a work board with a different thickness of copper foil on one side and the other side. I do. That is, the thickness Cs of the copper foil 533 on one side of the work board 14 is set to the value of the copper foil 5 on the other side.
34, which is thinner than the thickness Cb.

Next, a plurality of wiring patterns 3 are formed on the inner peripheral portion of the insulating substrate 2 by etching or the like on one side of the work substrate 14 having a thin copper foil.
Next, the work board 14 is turned over and the other side of the work board 14 having a thick copper foil is subjected to etching or the like, so that the outer periphery of the insulating board 2 is surrounded by the copper foil 534 so as to surround the entire circumference. A metal frame layer 54 consisting of only the metal frame is formed. Thus, the work board 14 provided with the metal frame layer 54 is formed. The metal frame layer 54
Has a thickness (Cb) of 75 μm. The thickness (Cs) of the wiring pattern 3 is 25 μm. The thickness T of the product part 4 is 130 μm, which is thin.

In the work board 14 of this embodiment, as described above, the wiring pattern 3 is formed from the thinner copper foil 533, and the metal frame layer 5 is formed from the thicker copper foil 534.
4 can be formed. Therefore, the thickness (Cb) of the metal frame layer 54 can be reliably changed by the difference between the thickness Cs of the metal foil 533 on one side of the work substrate 14 and the thickness Cb of the metal foil 534 on the other side.
Thickness (Cs).

As described above, the metal frame layer 54 is formed on the work substrate 14 by etching or the like.
Can be easily formed integrally. Therefore, it is not necessary to attach the backups 71 and 72 shown in the conventional example, and it is possible to efficiently mount electronic components. In addition, this embodiment also has the same operation and effect as the first embodiment.

When etching or the like is performed on one side of the work substrate 14, the copper foil 535 is left around the entire periphery of the insulating substrate 2 so as to surround the entire periphery, and the surface is plated. To form the metal plating film 555.

[0041]

As described above, according to the present invention, there is provided a work board capable of preventing warpage of a board and mounting electronic components accurately and easily on a product portion to be a printed wiring board. can do.

[Brief description of the drawings]

FIG. 1 is a sectional view of a work substrate according to a first embodiment.

FIG. 2 is a schematic view of a work board according to the first embodiment.

FIG. 3 is an explanatory view of a work substrate during transfer according to the first embodiment.

FIG. 4 is a perspective view of a work board according to the first embodiment.

FIG. 5 is a cross-sectional view of a work substrate according to a second embodiment in which metal frame layers are formed on both sides.

FIG. 6 is a schematic view of a work substrate according to a third embodiment in which a metal frame layer is provided in a strip shape.

FIG. 7 is a cross-sectional view of a work board formed of only a copper foil in a fourth embodiment.

FIG. 8 is a schematic view of a work substrate in a conventional example.

FIG. 9 is a sectional view of a work substrate in a conventional example.

FIG. 10 is an explanatory view of a work substrate during transfer in a conventional example.

FIG. 11 is an explanatory diagram of a backup in a conventional example.

[Explanation of symbols]

 1. . . Work board, 2. . . 2. insulating substrate; . . Wiring pattern, 4. . . Product Department, 5. . . Metal frame layer, 53. . . 55. copper foil (metal foil); . . Metal plating film,

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Takema Adachi 3-200, Kawamacho, Ogaki-shi, Gifu Ibi Inside the Kawama Plant (72) Inventor Hiroyuki Kobayashi 3-200, Kawamacho, Ogaki-shi, Gifu Ibi Inside the Kawama Plant of Den Co., Ltd. (72) Inventor Kenji Chihara 3-200, Kawamacho, Ogaki City, Gifu Prefecture IBIden Co., Ltd. Kawama Plant F-term (reference) 5E338 AA01 AA02 AA16 BB31 BB61 BB72 BB75 CC01 CD11 EE24 EE26 EE32

Claims (8)

[Claims] In a work board provided with a product part to be a printed wiring board, an outer peripheral portion of the work board is provided on a work board.
A work board, wherein a metal frame layer is formed outside the product part, and the thickness of the metal frame layer is larger than the thickness of a wiring pattern provided on the product part. 2. The work substrate according to claim 1, wherein said metal frame layer has a thickness of 25 to 100 μm. 3. The method according to claim 1, wherein the difference between the thickness of the metal frame layer and the thickness of the wiring pattern is 15 to 15.
A work substrate having a thickness of 90 μm. 4. The method according to claim 1, wherein:
A work board, wherein the metal frame layer is formed on one side of the work board. 5. The method according to claim 1, wherein:
A work board, wherein the metal frame layer is formed on both sides of the work board. 6. The method according to claim 1, wherein:
The work board, wherein the metal frame layer is formed so as to surround the entire periphery of the outer periphery of the work board. 7. The method according to claim 1, wherein:
A work board, wherein the metal frame layer is provided in a strip shape along the board flow direction when the work board is mounted. 8. The method according to claim 1, wherein:
The work board according to claim 1, wherein the metal frame layer comprises a metal foil and a metal plating film.