JPH0621657A - Checking pattern for layer organization of multilayer print wiring board - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide a layer knitting check pattern for a layered knitting check pattern in a multilayer printed wiring board, which is capable of surely detecting an error in the layer knitting of a substrate. [Structure] A plurality of IVHs 11, 1 drilled at a depth from the surface layer substrate 1 to the intermediate thickness position of each inner layer substrate 2, 3 ,.
2, ..., the surface layer substrate 1 and the inner layer substrates 2, 3 ,.
Inner layer check patterns 32, 33 formed on the surface of the
, And the inner layer check patterns 32, 33, ... In the regular layer knitting, the inner layer check patterns 32, 33 ,. It is arranged so as to be connected to the only other inner layer check pattern.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a layer knitting check pattern for a multilayer printed wiring board.

[0002]

2. Description of the Related Art A multilayer printed wiring board is formed by stacking a plurality of inner layer substrates and surface layer substrates in a predetermined order and press-bonding them, and a circuit pattern formed on the front surface or both surfaces of each substrate.
They are connected to each other by through holes or IVH.

The stacking order of the inner layer substrate and the surface layer substrate, that is, the layer knitting of the substrate must be a regular knitting based on the intended circuit design. However, since each board is usually stacked manually, there is room for human error such as making a mistake in the stacking order of each board or stacking the same board in duplicate. Marks and numbers are printed on the label, and after the lamination process, the marks and numbers are visually checked to see if the layer composition is correct.

For example, as shown in FIG. 3, in a multilayer printed wiring board in which two surface layer substrates 1a and 1b and three inner layer substrates 2, 3 and 4 are laminated, the positions are arranged on the side end faces of the respective substrates. Marks 50 are provided which are printed while being sequentially shifted in the direction. When observed from the side when the stacking of the respective substrates is completed, the marks 50 are arranged in a stepwise pattern only in the case of regular layer formation, and the marks 50 appearing in the wrong layer formation are arranged. Can be distinguished, and correctness of layer formation can be determined.

Further, as shown in FIG. 4, for example, by utilizing the fact that each substrate is transparent or semi-transparent, the number 5 indicating the stacking order is placed outside the circuit pattern region of each substrate.
1 is formed by shifting the printing position for each substrate, and an opaque light shielding pattern 52 having a different area from that of the number 51 is formed in a region subsequent to the number 51.

When the above-mentioned substrates are stacked and observed from above, the number 51 can be read when it is above the light-shielding pattern 52, but is hidden when it is below the light-shielding pattern 52 and cannot be read. Therefore, when they are stacked in a regular layer formation, as shown in Fig. 4 (a),
Although the arrangement of the number 51 arranged in ascending order from "1" can be confirmed, as shown in Fig. 4 (b), a part of the number 51 is concealed by the light-shielding pattern 52 in the wrong layer formation, and the above-mentioned permutation is performed. (In the illustrated example, the number "2" of the inner layer substrate 2 is the light shielding pattern 5 of the inner layer substrate 3).
2 is concealed, and a missing number occurs), and correctness of layer formation can be determined.

[0007]

However, even when the layer knitting is checked by the marks 50 printed on the end faces of the above-mentioned respective substrates, the judgment of the naked eye is ultimately required, and the plates of the surface layer substrate and the inner layer substrate are also decided. Since the thickness is small, the mark 50 itself is difficult to see, and an error in layer formation may be overlooked.

Further, even when checking the layer knitting with the number 51 and the light shielding pattern 52 printed on the surface of the substrate, since the judgment depends on the naked eye similarly to the above, there is a possibility that it may be overlooked and the number of layers is large. In the printed wiring board, it is difficult to check the numbers of the lower layer substrate and the surface layer substrate 1a due to the decrease in transparency, and thus there is a drawback that the check becomes difficult.

The present invention has been proposed in view of the above circumstances, and it is an object of the present invention to provide a layer knitting check pattern capable of surely detecting an error in the layer knitting of a substrate.

[0010]

In order to achieve the above object, the present invention employs the following means. That is, for example, as shown in FIGS. 1 and 2, the surface layer substrate 1 (1a, 1b)
To a plurality of IVHs 11, 12, ... Perforated at a depth from the inner layer substrates 2, 3, ... to the intermediate thickness position, and on the surface of the surface layer substrate 1 and each of the interior substrates 2, 3 ,. And inner layer check patterns 32, 33, ...
H11, 12, ... And the inner layer check pattern are the above-mentioned inner layer check patterns 32, 33, in the regular layer knitting.
Are the IVHs 11, 12, ... Which are different in order, and are the layer knitting check patterns of the substrate arranged so as to be connected to the only other inner layer check pattern.

[0011]

According to the above construction, all IVHs 11, 12, ... Are electrically connected by the inner layer check patterns 32, 33, .. At the same time as the continuity test, it is possible to determine whether the layer knitting is correct by detecting whether or not there is continuity between two appropriately selected IVHs.

[0012]

1 is a sectional view of an embodiment according to the present invention. In this embodiment, a surface layer substrate 1a (1), an inner layer substrate 2,
The present invention is applied to a multilayer printed wiring board in which a total of five substrates 3, 4, and the surface layer substrate 1b (1) are sequentially laminated.

In this embodiment, in the regular layer knitting, FIG.
As shown in (a), three IVHs 11, which are drilled at different depths from the surface outside the circuit pattern area of the surface layer substrate 1a (1) to the intermediate thickness position of the inner layer substrates 2, 3 and 4, 1
2 and 13 and two IVHs 14 and 15 drilled at different depths from the surface outside the circuit pattern region of the surface layer substrate 1b (1) to the intermediate thickness position of the inner layer substrates 3 and 4. All the IVHs 11 to 15 are electrically connected by the inner layer check patterns 32 to 35 formed on the surfaces of the surface layer substrate 1b (1) and the inner layer substrates 2 to 4.

Each inner layer check pattern 32 to 35 described above
Is formed simultaneously with the patterning of the circuit pattern on the surfaces of the inner layer substrates 2, 3, 4 and the surface layer substrate 1b, the position in the plate thickness direction changes corresponding to the layer knitting, and Connection with IVHs 11-15 with different height
The state of non-connection will change, and only in the regular layer formation, adjacent IVHs will be connected by a unique inner layer check pattern.

Therefore, for example, as shown in FIG. 1B, when the inner layer substrate 2 and the inner layer substrate 3 are mistakenly replaced and stacked, the IVH 11 and the IVH 12 should be connected by a regular layer formation. The inner layer check pattern 32 of
No connection to VH11, IVH11 and IVH
The insulation between 12 and 12 is established.

As described above, in the present embodiment, in the wrong layer formation, among the combinations having two IVHs as one set, the set which is not conducted by the inner layer check patterns 32 to 35 is
At least one set is generated, and in this embodiment, IVH11 and IVH15 among the plurality of IVHs 11 to 15 are generated.
By conducting a continuity test with a resistance detector, for example, it is possible to confirm whether or not there is a regular layer knitting.

FIG. 2 is a sectional view of another embodiment according to the present invention. In this embodiment, inner layer check patterns 32 to 35 are provided at the same positions as those of the embodiment shown in FIG. The five IVHs 11 to 15 are surface layers 1
The holes are formed from outside the circuit pattern region on the a side. Therefore,
In the case of regular layer formation shown in Fig. 2 (a), all IVH
11 to 15 are electrically connected by the inner layer check patterns 32 to 35.

On the other hand, as shown in FIG. 2 (b), when the inner layer substrate 2 and the inner layer substrate 3 are mistakenly replaced and stacked,
In the regular layer formation, the inner layer check pattern 32 connecting between IVH11 and IVH12 is not connected to IVH11, so that IVH11 and IVH12 are insulated and IVH11 and IVH15 are not electrically connected.

In the above two embodiments, only the case where the stacking order of the respective substrates is wrong is illustrated. However, even when the same substrates are stacked in duplicate, the position of the inner layer check pattern in the plate thickness direction will be described. Will shift from the position of the regular layer knitting, and a combination of two adjacent IVHs that is not electrically connected will be produced, so that the layer knitting can be checked in the same manner as described above.

Further, in the above-mentioned embodiment, the IVHs are arranged in a horizontal row in the order of the drilling depth, but the invention is not limited to this. For example, the IVHs can be arranged in an annular shape and the position where the inner layer check pattern is formed. It can be arbitrary according to the combination of.

Furthermore, it is not essential that the layer formation check pattern is formed outside the area of the circuit pattern as in the above embodiment, and the conductor pattern and IVH satisfying the above conditions at the stage of the intended circuit design. Can be formed in the pattern area and used as a layer knitting check pattern.

[0022]

As described above, according to the present invention, it is possible to check the correctness of the layer knitting of the multilayer printed wiring board by electrical conduction / non-conduction without the naked eye, so that the error of the layer knitting can be prevented. Since it can be surely found before shifting to the process of 1, there is an effect that the process loss can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment according to the present invention.

FIG. 2 is a sectional view of another embodiment according to the present invention.

FIG. 3 is a perspective view of a conventional example.

FIG. 4 is a conceptual diagram of another conventional example.

[Explanation of symbols]

 1 (1a, 1b) surface layer substrate 2, 3, ... inner layer substrate 11, 12, ... IVH 32, 33, ... inner layer check pattern

Claims (1)

[Claims] 1. The surface layer substrate (1) to each inner layer substrate (2), (3), ...
Of multiple IVHs (1
1), (12), ..., and the above surface layer substrate (1) and each inner layer substrate (2),
(3), inner layer check pattern formed on the surface of (32),
(33), ... and the above IVH (11), (12), ... and inner layer check pattern (32),
(33), ... In the regular layer knitting, the above-mentioned inner layer check patterns (32), (33), ... are different IVH (11), (12),
The pattern for checking the layer knitting of the multilayer printed wiring board arranged so as to be connected to the only other inner layer check pattern.