JP2006066632A - Circuit board and its inspection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure and an inspection method therefor, the structure surely inspecting insulation characteristics difficult to be done only with visual observation as for insulating layers of a circuit board equipped with a jumper structure. <P>SOLUTION: The circuit board (printed wiring board ) equipped with a copper foil layer formed on at least one surface thereof includes the jumper structure in a part of a conductor pattern on the surface thereof, and further includes a confirmation mark 300 independently of the conductor pattern and the insulating layers on a part of the surface of a base member. Insulating layers are formed on the surface of the confirmation mark corresponding to the formation of a plurality of the insulating layers. Thereafter, electric characteristics of the insulating layers are measured by bringing an inspection terminal of a check device into contact therewith. Consequently, the electric characteristics including insulation characteristics together with information of missing of any insulating layer of the plurality of the insulating layers are automatically inspected additionally to inspection by visual inspection. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

In the present invention, after a predetermined conductor pattern is formed on the surface of a base material formed by forming a conductor layer on the surface of an insulating material, an insulator is further applied to the surface to form an insulating layer. The present invention relates to a circuit board (printed wiring board) having a so-called jumper structure in which a conductor layer is formed, and a method for inspecting the circuit board.

Conventionally, for example, in a so-called insulating substrate (base material) such as a glass epoxy substrate or a paper phenol substrate on which one side or both sides of a copper foil is formed, the copper foil on the surface is removed by etching or the like (or a circuit) ) A pattern is formed, and further an insulator including a solder resist (solder resist) is applied to the surface to form an insulating layer, and a conductive pattern (jumper) is formed on the surface using a conductive paint. The printed circuit board has already been disclosed, for example, in Patent Document 1 below.
Is known by.

In addition, when forming the conductive pattern (jumper), as a method for checking printing deviation of the insulating layer and missing process, a structure that makes the inspection easy by changing the color of the insulating ink forming the insulating layer And the method are already known from Patent Document 2 below.
JP-A-6-140788 JP-A-9-331138

That is, as pointed out in Patent Document 2, when a printed electronic element such as a printed resistor or a conductive pattern is formed on a copper foil circuit pattern, in order to increase the density, Printed electronic elements and conductor patterns (so-called, via a solder resist layer and an insulating layer)
A jumper) may be formed. In that case, if the thickness of the formed solder resist layer or insulating layer is thin, a short circuit may occur between the copper foil circuit pattern and the printed electronic element or conductive pattern. In view of this, the insulating layer is formed in multiple layers, so that the thickness of the insulating layer is ensured. However, when the insulating layer is formed of a plurality of layers, the number of printing steps for that increase. Furthermore, it is necessary to confirm the formation state of the formed insulating layer.

Therefore, in the above-mentioned Patent Document 2, in particular, printing misalignment or omission of each layer of the insulating layer,
In order to facilitate inspection by so-called visual inspection, a part of the insulating layer to be printed is formed of a transparent member, and other insulating layer members are also made of materials having colors that are distinguishable from each other. Printed circuit boards have been proposed.

However, in the printed circuit board known from the above-mentioned Patent Document 2, it is premised that some printing deviation occurs in each layer of the insulating layer to be formed in order to enable visual inspection. Therefore, when these multiple layers are formed on each layer with high accuracy in order to increase the density (especially between the layers formed below the colored layer), visual inspection thereof is performed. There was a problem that became difficult. In addition, only by visual inspection, including the missing of the formed insulating layer, in particular, due to the electrical characteristics of the formed insulating layer, that is, the formation state including the thickness of each layer of the formed insulating layer. It has been difficult to reliably confirm the insulation properties. In addition, it is possible to control the insulating ink in the manufacturing process of the printed wiring board by making each layer of the formed insulating layer a color that can be distinguished from each other including transparent and surely controlling the order of applying them. In addition, since it also affects the insulation characteristics, it is often difficult to adopt it in an actual manufacturing process.

Therefore, in the present invention, in view of the above-described problems in the prior art, a printed wiring comprising a plurality of insulating layers formed on a conductor pattern of a circuit board and a conductor layer (so-called jumper) formed on the surface thereof. Confirmation of the formation of multiple insulation layers on a substrate, including the formation of multiple insulation layers, including the insulation characteristics that are difficult to achieve by conventional visual inspection alone, such as the insulation properties. It is an object of the present invention to provide a circuit board capable of making it possible and an inspection method for such a circuit board.

That is, in order to achieve the above-described object of the present invention, the present invention provides an insulating substrate and a conductor pattern formed on at least one surface of the insulating substrate. A circuit board in which an insulating layer is formed on a part of the surface of the conductor pattern formed on the surface of the insulating substrate, and further the conductor pattern and the insulating layer formed on the surface of the insulating substrate. Independently, a confirmation mark for confirming formation of the plurality of insulating layers is provided on a part of the insulating substrate, and the confirmation mark is formed on each surface corresponding to the formation of the insulating layer. A circuit board is provided that includes a conductor layer having a predetermined shape in which an insulating layer is individually formed and is electrically connected therebetween.

  According to the present invention, there is provided an insulating substrate and a conductor pattern formed on at least one surface of the insulating substrate, and further, a part of the surface of the conductor pattern formed on the surface of the insulating substrate. Is a circuit board formed by forming an insulating layer and forming a conductor layer on the surface of the insulating layer, wherein the insulating layer is formed of a plurality of layers and further formed on the surface of the insulating substrate. Independently of the conductor pattern and the insulating layer, a confirmation mark for confirming the formation of the plurality of insulating layers is provided on a part of the insulating substrate, and the confirmation mark includes the plurality of insulating layers. Corresponding to the formation of the layers, there is provided a circuit board that includes a plurality of conductor layers having a predetermined shape, each of which has an insulating layer individually formed on each surface, and is electrically connected therebetween.

According to the present invention, in the circuit board described above, the confirmation mark is a conductor layer having a predetermined shape in which an insulating layer is individually formed on each surface corresponding to the formation of the plurality of insulating layers. Are provided and are electrically connected to each other, or the confirmation mark is formed on the discarded substrate portion.

Furthermore, according to the present invention, there is provided an inspection method for a circuit board as described above, wherein the surface of the confirmation mark formed on a part of the insulating substrate independently of the conductor pattern and the insulating layer. In addition, after forming the insulating layers individually on the respective surfaces in correspondence with the formation of the plurality of insulating layers, the contact terminals are contacted and the electrical characteristics are measured to form a part of the conductor pattern. An inspection method for a circuit board for inspecting electrical characteristics of the plurality of insulating layers is provided.

According to the present invention, in the inspection method for a circuit board described above, the method for inspecting the electrical characteristics of the plurality of insulating layers may be inspected simultaneously with the circuit continuity check of the conductor pattern.

That is, according to the present invention described above, by using the confirmation mark formed on a part of the circuit board described above, a plurality of insulating layers formed on the conductor pattern to form a jumper structure, With the above-described inspection method, it is possible to inspect reliably, automatically, and efficiently, including the insulation characteristic that is an electrical characteristic that is difficult only by visual inspection.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, attached FIG. 1 is a base material used for forming a circuit board (or a printed wiring board) according to an embodiment of the present invention, and a copper foil (for example, A so-called insulating substrate (base material) 100 such as a glass epoxy substrate, a paper phenol substrate, or the like on which a conductive layer having a thickness of about 35 μm is formed is shown. As is clear from this figure,
In this insulating substrate (base material) 100, as will be described in detail below, the metal foil attached to one or both surfaces thereof is etched in a predetermined pattern, for example, in the inside surrounded by the broken line in the figure, etc. To form a desired circuit (conductor) pattern. Furthermore, a part of the surface of the circuit (conductor) pattern on the surface includes, for example, a solder resist, and an insulating layer is formed by printing and applying an insulator (insulating ink), and the conductor layer is formed on the surface. (So-called jumper) is formed, and thus a printed wiring board having a so-called jumper structure is formed.

The insulating substrate (base material) 100 on which a desired circuit (conductor) pattern is formed is cut into broken printed wiring boards (products) 200 and 200 in the drawing. On the other hand, the portion outside the broken line forms a frame portion for holding the insulating substrate (base material) 100 and is removed after an element is mounted on the printed wiring board. This is called a discarded substrate (a portion to be removed except for the product portion) 150. In addition, the printed wiring boards 200 and 200 in the broken line portion in the figure may not be the same shape, but may be a combination of printed wiring boards having different shapes.

And according to this invention, the confirmation mark 300 explained in full detail below is formed in a part of surface of the said insulated substrate (base material) 100. FIG. Note that the confirmation mark 300 may be formed, for example, in a portion called the discarded substrate 150 of the base material 100 as shown in FIG. 1 or the broken line as shown by a dotted line in the drawing. Printed wiring board (product) 200, 2
It may be formed inside 00. When formed inside the printed wiring board 200, the confirmation mark 300 is independent of a conductor pattern, an insulating layer, or the like that is practically formed on the product, for example, electrically or physically. Will be formed.

An example of the pattern shape of the confirmation mark 300 is shown in FIG. As is clear from these drawings, the confirmation mark 300 is, for example, a part of the substrate 100 (for example,
Excess copper foil is removed by etching or the like in the portion called the discard substrate 150) to form a plurality of (in this case, three) circular lands 301, 302, 303 and a thin conductor path between them. 304 and 304 are electrically connected. More specifically, in this example, for example, the lands 301 and 303 have a diameter of 1.6.
On the other hand, the land 302 is formed with a diameter of 1.3φ. Further, the width of the conductor path 304 is, for example, 0.3 mm. Then, the land 301 having the large diameter (1.6φ) described above.
And 303, the surface of the printed wiring board (product) 200, 200 is coated with an insulator such as a solder resist to form an insulating layer. For example, it will be formed in the outer region with a diameter of 1.3φ.

Next, referring to FIG. 3 attached, the printed circuit boards 200 and 200 are formed using the insulating substrate (base material) 100 described above, and the insulating property that is an electrical characteristic of the formed insulating layer such as a solder resist is formed. A method for manufacturing a printed wiring board including a method for inspecting characteristics will be described.

In FIG. 3, first, in order to obtain the insulating substrate (base material) 100, a large-area material such as a glass epoxy substrate or a paper phenol substrate on which a copper foil is formed and attached on one side or both sides thereof is cut. Then, a material having a predetermined size and shape is obtained (step S10), and the end face is further processed (step S10).
Step S11). Subsequently, the printed wiring board 2 is formed on the copper foil formed on one side or both sides.
Along with the conductive pattern for forming 00, the confirmation mark 300 (land 301, 30
2 and 303 and the conductor path 304), a pattern printing of an etching resist is performed (step S12), and then an unnecessary copper foil is removed by an etching process to form a desired conductor pattern on the insulating substrate. As a result, the insulating substrate (base material) 10 shown in FIG.
Get 0. Further, if necessary, resist printing for printing a solder resist on the surface is performed (step S13).

Subsequently, undercoat printing I (step S14) is performed in order to form a plurality of insulating layers for forming a conductor pattern (so-called jumper) via a solder resist layer on the copper foil circuit portion.
) And undercoat printing II (step S15). At this time, in the present invention, the undercoat printing is performed using the confirmation mark 300.

Here, a jumper structure of the printed wiring board 200 formed on the insulating substrate (base material) 100 will be described with reference to a partially enlarged sectional view of FIG. This jumper structure is a portion of a conductor pattern 202 shown in the center of the figure in copper foils 201, 202, and 203, which are conductor patterns formed (remained) on an insulating substrate (base material) 100 by etching. The conductor patterns 201 and 203 on both sides thereof are electrically connected to each other. Specifically, first, a solder resist layer 204 including the conductor pattern 202 is formed on the surface of the printed wiring board. In addition, the code | symbol 204 in a figure is the said resist printing (process S13).
The soldering resist layer formed by is shown. The solder resist film 204 can be counted (counted) as the number of insulating layers. Furthermore, as will be described below, a first insulating layer 205 and a second insulating layer 206 formed by undercoat printing are sequentially formed on the surface. Thereafter, a conductor layer 207 is formed on the surface with a conductive paste so as to cover the conductor patterns 201 and 203 on both sides, and an overcoat 20 is further formed thereon.
8 is formed, thereby completing the jumper structure. The insulating layer and the conductor layer can be printed by adopting a general printing technique such as screen printing, for example.

Here, returning to FIG. 3 again, the surface of the solder resist layer 204 is covered with the first insulating layer 2.
Undercoat printing I for forming 05 is performed (step S14). At the same time as this printing is performed, undercoat printing I is also performed on the confirmation mark 300. That is, in this example, as shown in FIG. 5A, the undercoat printing I is performed on one circular land 301 constituting the confirmation mark 300 (see reference numeral 305). Similarly, undercoat printing II for forming the second insulating layer 206 is performed (step S15) and at the same time on the other circular land 303 of the confirmation mark 300. In this example, as shown in FIG. 5B, the undercoat printing II is performed on the circular land 303 on the other side of the confirmation mark 300 (see reference numeral 306). Note that undercoat printing on the confirmation mark 300 is performed at the same time as the undercoat printing I and II are performed, and at a portion corresponding to the position of the confirmation mark 300 (in this example, a diameter 1). This is realized by printing with a 3φ circle.

Furthermore, by printing the conductive paste in a predetermined shape (step S16), for example,
As shown by the reference numeral 207 in FIG. 4, a so-called jumper structure is formed which electrically connects the conductor patterns 201 and 203 on both sides beyond the conductor pattern 202 at the center. The actual printed wiring board manufacturing method is not directly related to the present invention, but thereafter, an overcoat is printed so as to cover the formed conductor layer 207 (step S17: symbol in FIG. 4 above). 208), and further, press working is performed to process the outer shape (step S18).

Thereafter, the printed wiring board completed as described above (however, it may be separated from the insulating base material 100 or may be in a state where it is not separated yet and the discarded substrate 150), I (step S14) and undercoat printing II (step S)
15) Using the above-mentioned confirmation mark 300 having the undercoat layers (insulating layers) 305 and 306 formed on the surface thereof in 15), the electrical characteristics of the circuit including the inspection are simultaneously checked with the same checking device. (Step S19).

More specifically, at this time, if the confirmation mark 300 is used, for example, as shown in FIGS. 5A and 5B, the confirmation mark 300 is individually formed in the vicinity. By comparing the circular lands 301 and 303 with the undercoat I layer 305 and the undercoat II layer 306 individually printed and formed on the respective surfaces, the printed pattern and the circuit pattern on the printed wiring board are compared. The deviation can be confirmed. That is, it is sufficient that the center of the circular land 301 or 303 of the confirmation mark 300 and the center of the undercoat I layer 305 or the undercoat II layer 306 coincide with each other. There is a deviation between the printed pattern and the circuit pattern on the printed wiring board. Note that the land 301 or 303 may be formed in a circular shape when determining whether or not the above-described misalignment is occurring and / or in which direction the misalignment is occurring. preferable.

In addition, according to the use of the confirmation mark 300, the attached FIGS.
), Check terminals 401, 402, 4 of the check device (for example, open / short checker) are formed on the surfaces of the circular lands 301, 302, 303 of the confirmation mark 300.
03, the electrical characteristics of the undercoat I layer 305 and the undercoat II layer 306 formed on the separate circular lands 301 and 303 in the vicinity automatically without depending on the visual check described above. It is possible to check the characteristic, that is, the insulation performance electrically and automatically. The inspection terminals 401, 402, and 40 described above are used.
Reference numeral 3 denotes a position corresponding to the confirmation mark 300 formed on the printed wiring board 200 or the insulating substrate 100 in the circuit continuity check (step S19). Positions corresponding to the formation positions of 301, 302, and 303 (
For example, the completed printed wiring board 200 or the insulating base material 100 is introduced into the inspection position at the same time as the contact with them is automatically performed.

As is clear from the above description, the confirmation mark 300, the inspection terminal 401,
According to the checker provided with 402, 403, by measuring the resistance value between the inspection terminals 401, 402, 403, or on a part of the circuit portion which is a conductor pattern on the printed wiring board 200 (or The undercoat I layer 305 and the undercoat II layer 30, which are a plurality of insulating layers printed and formed to form a jumper-structured conductor layer 207.
6 can be measured. That is, by measuring the resistance value between the inspection terminals 401 and 402, the insulation characteristic of the first insulating layer made of the undercoat I layer 305 is on the other hand, the resistance value between the inspection terminals 402 and 403. By measuring the above, the insulating characteristics of the second insulating layer made of the undercoat II layer 306 can be understood. That is, regarding the plurality of insulating layers, whether or not they are formed with a sufficient thickness for forming a jumper structure, including defects in formation (including missing process), automatically, And it becomes possible to check reliably.

In this example, after the above-described circuit continuity check (step S19) is executed, the product (in a state where it is separated from the insulating base material 100 or in a state where it has not been separated yet and is still with the discarded substrate 150). Good) will be shipped (step S20).

In the above detailed description, the confirmation mark 300 is, for example, three circular lands 3.
The configuration has been described by forming 01, 302, and 303 and electrically connecting them between the thin conductor paths 304 and 304. That is, two lands 301 and 303 are formed corresponding to the undercoat I layer 305 and the undercoat II layer 306, which are two insulating layers for forming a jumper structure on the printed wiring board 200. The land 302 for contacting the inspection terminal is added to obtain three. In other words, the number of lands formed can be expressed as (number of insulating layers to be inspected) + (terminal contact land) = 3.

However, the present invention is not limited to the above-described embodiment. For example, the number of land formations is the number of insulating layers to be inspected (the number of land formations = the number of insulating layers to be inspected). Specifically, in the above example, two circular lands 301 and 303 are used, and a part of the thin conductor path 304 formed between them may be used for contact with the inspection terminal. Good. Alternatively, as shown in FIG. 7 attached, lands 301 and 303 for forming the undercoat I layer 305 and the undercoat II layer 306 are arranged side by side, and a land 302 for contacting the inspection terminal at one end thereof. Furthermore, they are formed as a single land, an insulating layer is formed on a part of the land corresponding to the formation of the insulating layer on the printed wiring board 200, and the remaining part is inspected. It can also be used to contact the terminals.

In the above embodiment, the lands 301 and 303 constituting the confirmation mark 300 are also described.
In particular, the shape (including the land 302) has been described as a circular shape, but in the present invention, the shape is not limited thereto, and other shapes such as a polygon such as a quadrangle and a triangle may be used. However, in particular, with respect to the shape of the lands 301 and 303, when the solder resist is applied to the inside of the printed wiring board (product) 200, the solder resist is also applied to the surface at the same time. This is convenient for visually inspecting the deviation of the solder resist in the plate (product) 200 (that is, confirming how much the deviation is in which direction), and preferably has a more circular shape.

It is a perspective view which shows an example of the external appearance of the insulated substrate (base material) which is a base material used in order to form the circuit board (printed wiring board) which becomes one embodiment of this invention. It is a top view which shows an example of the confirmation mark formed in a part of said insulating substrate (base material). It is process drawing explaining an example of the method of manufacturing a circuit board (printed wiring board) with the said insulated substrate (base material). It is a partially expanded sectional view for demonstrating an example of the jumper structure formed in the said circuit board (printed wiring board). It is a figure for demonstrating the utilization method of a confirmation mark, ie, the relationship with the 1st and 2nd insulating layer formed on a confirmation mark. It is a figure for demonstrating the relationship between the said confirmation mark and the test | inspection terminal of a check apparatus. It is a top view which shows an example of the modification of the said confirmation mark.

Explanation of symbols

100 Insulating substrate (base material)
200 Printed wiring board 201, 202, 203 Copper foil (conductor pattern)
205 First insulating layer (undercoat I)
206 Second insulating layer (undercoat II)
207 Conductor layer 300 Confirmation mark 301, 302, 303 Land 305 Undercoat I layer 306 Undercoat II layer 401, 402, 403 Inspection terminal.

Claims (5)

An insulating substrate and a conductor pattern formed on at least one surface of the insulating substrate; and an insulating layer is formed on a part of the surface of the conductor pattern formed on the surface of the insulating substrate. And a confirmation for confirming the formation of the insulating layer on a part of the insulating substrate independently of the conductor pattern and the insulating layer formed on the surface of the insulating substrate. Corresponding to the formation of the insulating layer, the confirmation mark includes a conductor layer having a predetermined shape on which the insulating layer is individually formed, and is electrically connected therebetween. A circuit board characterized by the above. In addition to providing an insulating substrate and a conductor pattern formed on at least one surface of the insulating substrate, and further forming an insulating layer on a part of the surface of the conductor pattern formed on the surface of the insulating substrate, A circuit board formed by forming a conductor layer on the surface of the insulating layer, wherein the insulating layer is formed of a plurality of layers, and further, the conductor pattern and the insulating layer formed on the surface of the insulating substrate Independently, a confirmation mark for confirming the formation of the plurality of insulating layers is provided on a part of the insulating substrate, the confirmation mark corresponding to the formation of the plurality of insulating layers, A circuit board comprising a plurality of conductor layers having a predetermined shape, each having an insulating layer formed individually on each surface, and electrically connected therebetween. 3. The circuit board according to claim 1, wherein the confirmation mark is formed on a discarded board portion. The inspection method for a circuit board according to any one of claims 1 to 3, wherein the surface of the confirmation mark is formed on a part of the insulating substrate independently of the conductor pattern and the insulating layer. In addition, after forming the insulating layers individually on the respective surfaces in correspondence with the formation of the plurality of insulating layers, the contact terminals are contacted and the electrical characteristics are measured to form a part of the conductor pattern. An inspection method for a circuit board, comprising: inspecting electrical characteristics of the plurality of insulating layers. 5. The inspection method for a circuit board according to claim 4, wherein the method for inspecting the electrical characteristics of the plurality of insulating layers is performed simultaneously with the circuit continuity check of the conductor pattern. Inspection method.

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