JP4737055B2 - Multilayer printed wiring board - Google Patents

Description

  The present invention relates to a laminated printed wiring board, and more particularly to a laminated printed wiring board in which positional deviation of a wiring layer can be easily visually confirmed.

  In general, with the reduction in size and weight of electronic devices, a multilayer printed wiring board is required to have a high-density and multi-layered board. Here, in the laminated printed wiring board (also referred to as “multilayer printed wiring board”), the wiring layer shift of each layer must be ensured to have a minimum state from the connection reliability. For this reason, at present, a certain amount of misalignment is taken into consideration, and the connected land pattern diameter and the non-connected land clearance diameter are increased to cope with the misalignment. However, with the recent miniaturization of electronic devices, the number of high-density laminated printed wiring boards is increasing, and the connected land pattern diameter and the non-connected land clearance diameter are in the direction of decreasing. For this reason, wiring layer defects due to misalignment cannot be ignored, and the misregistration management of each layer is further required.

  Usually, the inspection of the multilayer printed wiring board is performed by mounting an electronic component or the like on the multilayer printed wiring board and conducting an energization test on the electronic component. However, if a problem caused by the multilayer printed wiring board is detected at this stage, the mounted electronic component is wasted. Therefore, it is desirable to be able to inspect in advance in a state of a single layer printed wiring board before mounting electronic components or the like.

  Therefore, as a more accurate method for confirming misalignment, a reference hole for position accuracy inspection is formed on the multilayer printed wiring board, and a ring-shaped position accuracy verification mark corresponding to the reference hole is simultaneously printed when the wiring layer is printed. There has been disclosed a method of confirming the positional deviation of the printing position as a deviation of the coaxiality between the reference hole and the positional accuracy verification mark by printing and adding (for example, Patent Document 1).

JP-A-10-68696

  However, in the structure as disclosed in Patent Document 1 as described above, when more wiring layers are stacked in multiple layers as in the current multilayer printed wiring board, it is difficult to visually recognize the pattern itself. There was a problem of becoming. Furthermore, there is a problem that it is difficult to specify which of the plurality of wiring layers is displaced.

  The present invention has been devised to pay attention to the above problems and to effectively solve them. The object of the present invention is not only to easily confirm the displacement of each wiring layer in the stage before mounting an electronic component etc., but also to identify which wiring layer is displaced. An object of the present invention is to provide a laminated printed wiring board that can be used.

The invention according to claim 1 is the laminated printed wiring board having a laminated structure in which a plurality of wiring layers are laminated, wherein each of the wiring layers is insulated by a core material or an insulating layer having an insulating property, Each of the misregistration confirmation patterns has an L-shape or a “<” shape for confirming misregistration between the wiring layers, and the misregistration confirmation patterns are arranged in the stacking direction of the respective wiring layers. A multilayer printed wiring board, wherein the wiring layers are formed so as to be shifted from each other in a direction orthogonal to each other at a predetermined interval .
According to a second aspect of the present invention, there is provided an insulating core material, a first wiring layer and a first misalignment confirmation pattern formed on one surface side of the core material, and one surface side of the core material. A second wiring layer and a second misregistration confirmation pattern formed on the first wiring layer and the first misregistration confirmation pattern via a first insulating layer, and the other surface of the core material A second wiring layer and a third positional deviation confirmation pattern formed on the side, and a second insulation on the third wiring layer and the third positional deviation confirmation pattern on the other surface side of the core material. A fourth wiring layer and a fourth misregistration confirmation pattern formed through the layers, wherein each of the first to fourth misregistration confirmation patterns is L-shaped or "<" Corresponding to wiring layers adjacent to each other in the first to fourth wiring layers. Formed so as to be adjacent to each other and at a predetermined interval for each of the first to fourth wiring layers in a direction orthogonal to the stacking direction of the first to fourth wiring layers It is the laminated printed wiring board characterized by the above-mentioned.

  According to the multilayer printed wiring board according to the present invention, it is possible not only to easily check the displacement of the wiring layers of each layer before mounting electronic components, but also to which layer of the wiring layer is displaced. Can be identified.

Hereinafter, an embodiment of a multilayer printed wiring board according to the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a process diagram showing a manufacturing process of a laminated printed wiring board according to the present invention, FIG. 2 is a partial plan view showing an arrangement relationship between each wiring layer and a misregistration confirmation pattern, and FIG. It is a fragmentary top view which shows a one part state when it sees.

  In FIG. 1, the completed multilayer printed wiring board 2 is shown in FIG. 1E, and this multilayer printed wiring board 2 has a plurality of wiring layers, specifically, first to fourth four layers. The wiring layers 6A, 6B, 6C, and 6D are provided, and the wiring layers 6A to 6D are insulated by the insulating core member 12 or the insulating layer 4, respectively, and the wiring layers 6A to 6D are displaced. Misregistration confirmation patterns 8A to 8D are provided. That is, one misregistration confirmation pattern is provided for one wiring layer. In this case, the insulating core member 12 is located at the center of the wiring layers 6A to 6D in the stacking direction, and the wiring layers 6A to 6D are stacked on both sides thereof.

  Here, a method for manufacturing the laminated printed wiring board 2 will be described. First, as shown in FIG. 1A, conductive layers 6 made of, for example, copper foil or the like are formed on the entire surface of both surfaces of the insulating core material 12. Then, the conductive layers 6 on both surfaces of the core material 12 are subjected to pattern etching, thereby forming the first and second wiring layers 6A and 6B as shown in FIG. At this time, the first and second misregistration confirmation patterns 8A and 8B are also formed at the same time.

  Next, as shown in FIG. 1C, insulating layers 4A and 4B are formed on the entire surfaces of the surfaces on which the first and second wiring layers 6A and 6B are formed. Conductive layers 6 made of, for example, copper foil are respectively formed on the entire surfaces of 4A and 4B, thereby forming a laminated structure as shown in FIG.

  Next, the conductive layers 6 are etched to form the third and fourth wiring layers 6C and 6D as shown in FIG. 1E. At this time, the third and fourth positions are simultaneously formed. Deviation confirmation patterns 8C and 8D are also formed. Thereby, the laminated printed wiring board 2 is completed.

  Each of the insulating layers 4A, 4B and the core member 12 is made of, for example, glass fiber as a base material, and is in a transparent or translucent state. Each of the insulating layers 4A and 4B has a thickness of about 0.1 to 2.0 mm, for example, and the core member 12 has a thickness of about 0.1 to 2.0 mm, for example. Each of the wiring layers 6A to 6D is a wiring pattern. Here, for convenience, all the wiring layers 6A to 6D have the same shape. However, each layer is actually patterned in an individual shape.

  The misregistration confirmation patterns 8A to 8D are formed by shifting the positions of the wiring layers 6A to 6D in the direction orthogonal to the stacking direction of the wiring layers 6A to 6D, that is, in the surface direction. . Specifically, as shown in FIG. 1A, the core member 12 is also used as an insulating layer, and between the adjacent wiring layers 6A to 6D, the misregistration confirmation patterns 8A to 8D are formed from the wiring layers 6A to 6A. The positions are shifted for each layer by a predetermined interval L1 according to the 6D stacking order. Here, all the misregistration confirmation patterns 8A to 8D are formed in a bar shape (bar shape).

  Therefore, as shown in FIG. 3, when the wiring layers 6 </ b> A to 6 </ b> D are not misaligned when viewed from one surface of the multilayer printed wiring board 2, the adjacent misregistration confirmation patterns 8 </ b> A to 8 </ b> A to FIG. The intervals L1 between the 8Ds are arranged so as to be constant, and are set to be a so-called zebra pattern.

  In this case, as shown in FIG. 2, each of the misregistration confirmation patterns 8A to 8D is formed in a linear shape or a rectangular shape, and the dimensions thereof are, for example, about 0.2 to 0.5 mm in length H1 and about width H2. Is, for example, about 1.0 to 2.0 mm. Here, it is desirable that the misregistration confirmation patterns 8A to 8D are also allocated and arranged so as to be adjacent to each other, corresponding to the wiring layers 6A to 6D adjacent to each other, but the present invention is particularly limited to this. In addition, the position of each of the misregistration confirmation patterns 8A to 8D may be assigned in any way.

  Each of the misregistration confirmation patterns 8A to 8D as described above may be formed at the same time when the corresponding wiring layers 6A to 6D are formed by printing, for example. Further, the misregistration confirmation patterns 8A to 8D are transparent or translucent insulating layers 4A and 4B and transparent or transparent when viewed from one side of the laminated printed wiring board 2 as shown in FIG. It is made of an opaque material that can visually recognize each of the misregistration confirmation patterns 8 </ b> A to 8 </ b> D through the translucent core material 12.

Now, when the laminated printed wiring board 2 formed as described above is viewed from any one of its surfaces, the state shown in FIG. 3 is obtained, and the misregistration confirmation patterns 8A to 8D of the respective layers are obtained. It can be visually recognized as a so-called zebra pattern.
Here, when only a certain wiring layer is laminated in a state where a positional deviation has occurred, only the corresponding positional deviation confirmation pattern 8 becomes a zebra pattern in an irregular state and can be easily recognized. For example, when the positional deviation confirmation pattern 8 is misaligned, the gap L1 between the adjacent positional deviation confirmation patterns 8 is widened or narrowed, and further protrudes in the lateral direction. Then, by identifying which layer the corresponding misregistration confirmation pattern 8 is, that is, to which wiring layer of the wiring layers 6A to 6D is assigned, the misaligned layer is specified. can do.

  As described above, according to the present invention, it is possible not only to easily check the displacement of the wiring layers of each layer before mounting the electronic component etc., but also which layer of the wiring layer is displaced. Can be specified.

Next, a modified example of the positional deviation confirmation pattern 8 will be described. FIG. 4 is a diagram showing a modification of the misregistration confirmation pattern. FIG. 4A shows a first modification, and FIG. 4B shows a second modification.
As shown in FIG. 3, here, the case of a set of zebra patterns composed of four misregistration confirmation patterns 8A to 8D has been described as an example. However, the present invention is not limited to this, and FIG. As in the first modification shown in FIG. 4, four additional misregistration confirmation patterns 10A, 10B, 10C, and 10D arranged in a direction rotated 90 degrees from the arrangement direction of the zebra pattern are formed in the same manner. You may make it arrange | position a pair.

  According to this, it is possible to visually recognize the direction of positional deviation more reliably. Further, as in the second modified example shown in FIG. 4B, the misregistration confirmation patterns 8A to 8D may be arranged in an L shape (or a “<”) shape. According to this, it is possible to recognize the direction of the positional deviation more reliably and to reduce the arrangement pace of the positional deviation confirmation patterns 8A to 8D.

  According to the multilayer printed wiring board 2 of the present invention, the zebra pattern composed of the misregistration confirmation patterns 8A to 8D or the misregistration confirmation patterns 8A to 8D and 10A to 10D is captured as an image by a sensor means such as a camera. If the image analysis is carried out, the inspection process can be automated. Further, even if the positional deviation confirmation pattern is minimized by increasing the density of the circuit pattern of the laminated printed wiring board, sensor means such as optical analysis can be used.

  Here, the case where the number of the insulating layers 4 is four has been described as an example, but it is needless to say that the number of layers is not limited. Further, here, the case where the wiring layer is laminated on both sides of the core material 12 has been described as an example, but the present invention is not limited to this, and the wiring layer is formed in multiple layers by interposing an insulating layer only on one side of the core material 12. You may make it laminate.

It is process drawing which shows the manufacturing process of the multilayer printed wiring board which concerns on this invention. It is a fragmentary top view which shows the arrangement | positioning relationship of each wiring layer and the pattern for position shift confirmation. It is a fragmentary top view which shows a partial state when a laminated printed wiring board is seen from the surface. It is a figure which shows the modification of the pattern for position shift confirmation.

Explanation of symbols

2 ... Laminated printed wiring board, 4A, 4B ... Insulating layer, 6, 6A-6D ... Wiring layer, 8A-8D, 10A-10D ... Misalignment confirmation pattern, 12 ... Core member.

Claims (2)

In a laminated printed wiring board having a laminated structure in which a plurality of wiring layers are laminated,
Each wiring layer is insulated by a core material or an insulating layer having an insulating property, and a positional deviation confirmation having an L shape or a “<” shape for confirming a positional deviation between the wiring layers. Each has a pattern for
Each of the misregistration confirmation patterns is formed by shifting the position with a predetermined interval for each wiring layer in a direction orthogonal to the laminating direction of each wiring layer. Printed wiring board. An insulating core material;
  A first wiring layer and a first misregistration confirmation pattern formed on one surface side of the core material;
  A second wiring layer and a second positional deviation confirmation pattern formed on the first wiring layer and the first positional deviation confirmation pattern on the one surface side of the core material via a first insulating layer; ,
  A third wiring layer and a third misregistration confirmation pattern formed on the other surface side of the core material;
  A fourth wiring layer and a fourth misalignment confirmation pattern formed on the third wiring layer and the third misalignment confirmation pattern on the other surface side of the core material via a second insulating layer. When,
With
  The first to fourth misregistration confirmation patterns each have an L shape or a “<” shape, and correspond to wiring layers adjacent to each other in the first to fourth wiring layers. Adjacent to each other and at a predetermined interval for each of the first to fourth wiring layers in a direction orthogonal to the stacking direction of the first to fourth wiring layers. A laminated printed wiring board characterized by comprising:

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