阅读说明：本技术 配线板 (Wiring board ) 是由 山本恵一郎 谷一夫 矢野正晴 于 2020-01-24 设计创作，主要内容包括：本发明提供一种即使由于制造误差而安装用焊盘的位置稍微偏离正规的位置,也能够正常地通过自动电路图案检查装置而检测电路图案的断线的配线板。本发明的配线板在表面设置第一安装用焊盘(4a)、第二安装用焊盘(4b)以及第一电路图案(6a)、第二电路图案(6b),在基板(2)的表面设置了与所述第一安装用焊盘(4a)、第二安装用焊盘(4b)电连接的第一电力检测用焊盘(10a)、第二检测用焊盘(10b)。(The invention provides a wiring board capable of normally detecting disconnection of a circuit pattern by an automatic circuit pattern inspection device even if the position of a mounting pad slightly deviates from a normal position due to manufacturing error. A wiring board is provided with a first mounting pad (4a), a second mounting pad (4b), a first circuit pattern (6a), and a second circuit pattern (6b) on the surface thereof, and a first power detection pad (10a) and a second power detection pad (10b) electrically connected to the first mounting pad (4a) and the second mounting pad (4b) are provided on the surface of a substrate (2).)

1. A wiring board having a mounting pad and a circuit pattern provided on a surface thereof, characterized in that,

a power detection pad electrically connected to the mounting pad is provided on the surface of the substrate.

2. The wiring board according to claim 1,

the mounting pad is used for mounting a chip component having a size standard smaller than "1005".

3. Wiring board according to claim 1 or 2,

the size of the mounting pad is less than 0.5mm, and the size of the power detection pad is 0.5mm or more.

4. The wiring board according to any one of claims 1 to 3,

a solder resist film is formed on the surface of the printed board except for the mounting pad and the peripheral portion thereof and the power detection pad and the peripheral portion thereof.

5. The wiring board according to any one of claims 1 to 4,

a resist gap between the mounting pad and the solder resist film is set to 0.15mm or more.

6. The wiring board according to any one of claims 1 to 5,

the design value of the ck resist cut between the adjacent mounting pad and the power detection pad was 0.15 mm.

7. The wiring board according to any one of claims 1 to 6,

the length of a circuit pattern connecting the mounting pad and the power detection pad is 0.45mm or more.

8. The wiring board according to any one of claims 1 to 7,

the power detection pad extends toward the outside of the chip component.

9. The wiring board according to any one of claims 1 to 8,

the power detection pad is circular or rectangular in shape.

Technical Field

The present invention relates to a wiring board, and more particularly, to a printed wiring board on which a small chip component such as "0603" which has a smaller size standard than that of so-called "1005" is mounted.

Background

In recent years, the demand for miniaturization of chip components by customers has been increasing, and in practice, the demand for the size of chip components has been increasing from "1005 (L: 1.0 mm. times.W: 0.5 mm)" to, for example, "0603 (L: 0.6 mm. times.W: 0.3 mm)".

Fig. 5 is a plan view showing a typical design standard in the case of a printed wiring board 40 on which a chip component is mounted with a size standard of "0603". "0603" chip component 100 is surface-mounted on a pair of mounting land patterns (hereinafter, simply referred to as mounting lands) 42a and 42 b. The mounting pads 42a and 42b are each 0.3mm square or0.3mm apart by 0.3 mm.

The solder resist 44 for protecting the mounting pads 42a and 42b from short circuits and the like is formed so that the offset tolerance with respect to the mounting pads 42a and 42b is ± 0.15mm, respectively (i.e., the resist gaps 45a and 45b are within 0.15 mm).

The mounting pads 42a and 42b are formed in a pattern within, for example, ± 0.05 to 0.15mm from the design position. These mounting pads 42a and 42b and solder resist 44 are formed by screen printing or the like.

The probes 46a and 46b of the automatic circuit pattern inspection device for detecting disconnection of the circuit pattern are preferably brought into contact with (pressed against) the central portions of the mounting pads 42a and 42b, respectively.

In order to form mounting pads on the surface of a printed circuit board, which require such a high-precision formation position, various screen printing techniques have been proposed in the related art. (see, for example, patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 6067135.

Disclosure of Invention

Problems to be solved by the invention

However, when various screen printing techniques of the related art are simply applied, since a manufacturing error occurs, an abnormal situation in which the positions of the mounting pads 42a and 42b are slightly shifted from the regular positions is likely to occur. Therefore, there is an abnormality that the needles 46a and 46b cannot normally contact the mounting pads 42a and 42b, respectively.

Further, due to the pressure contact force of the probes 46a and 46b against the surfaces of the mounting pads 42a and 42b, depressions are generated on the surfaces of the mounting pads 42a and 42b, and the chip component 100 may be surface-mounted in a defective state.

Accordingly, a main object of the present invention is to provide a wiring board capable of normally detecting disconnection of a circuit pattern by an automatic circuit pattern inspection apparatus even if the position of a mounting pad is slightly deviated from a normal position due to a manufacturing error.

Means for solving the problems

The present inventors have conducted extensive studies to solve the above problems, and have found that the above problems can be solved by the invention described below, and have completed the present invention.

That is, as described above, if the position of the mounting pad is slightly deviated from the normal position due to the manufacturing error, the probe pin is deviated from the region of the mounting pad, and the accurate wire breakage inspection cannot be performed. Therefore, the inventors of the present invention have found that the above-described problems can be solved by providing a large-area power detection pad while securing a vacant region near the mounting pad, unlike the mounting pad, and by bringing the probe pin into contact with the power detection pad instead of the mounting pad.

The wiring board of the present invention is a wiring board having a mounting pad and a circuit pattern on a surface thereof, and a power detection pad electrically connected to the mounting pad is provided on a surface of a substrate.

In the wiring board of the present invention, the mounting pads are used for mounting chip components having a size standard smaller than "1005".

In the wiring board of the present invention, it is preferable that the size of the mounting pad is smaller than 0.5mm and the size of the power detection pad is 0.5mm or more.

In the wiring board of the present invention, it is preferable that a solder resist film is formed on the surface of the printed circuit board in addition to the mounting pad and the peripheral portion thereof, and the power detection pad and the peripheral portion thereof.

In the wiring board of the present invention, it is preferable that the resist gap between the mounting pad and the solder resist is 0.15mm or more.

In the wiring board of the present invention, it is preferable that the ck resist between the adjacent mounting pads and the power detection pads be cut to 0.15 mm.

In the wiring board of the present invention, it is preferable that the length of the circuit pattern connecting the mounting pad and the power detection pad is 0.45mm or more.

In the wiring board of the present invention, the power detection pad preferably extends toward the outside of the chip component.

In the wiring board of the present invention, the power detection pad is preferably circular or rectangular in shape.

Effects of the invention

According to the present invention, a wiring board is obtained which can normally detect disconnection of a circuit pattern by an automatic circuit pattern inspection apparatus even if the position of a mounting pad is slightly deviated from a normal position due to a manufacturing error.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings.

Drawings

Fig. 1 is a plan view showing a wiring board according to a first embodiment of the present invention.

FIG. 2 is a sectional view of FIG. 1, (A) is a sectional view of line IIA-IIA of FIG. 1, (B) is a sectional view of line IIB-IIB of FIG. 1, (C) is an end view of line IIC-IIC of FIG. 1, and (D) is an end view of line 1ID-IID of FIG. 1.

Fig. 3 is a flowchart illustrating a method of manufacturing the wiring board.

Fig. 4A is a plan view showing a wiring board of the second embodiment of the present invention.

Fig. 4B is an end view or a sectional view of fig. 4A, (B) is an end view of line IIIB-IIIB of fig. 4A, (C) is a sectional view of line IIIC-IIIC of fig. 4A, and (D) is a sectional view of line IIID-IIID of fig. 4A.

Fig. 5 is a plan view showing a general design standard of a chip component having a size standard of "0603".

Detailed Description

1. Structure of wiring board

[ first embodiment ]

A first embodiment of the wiring board of the present invention will be explained.

Fig. 1 is a plan view showing a wiring board according to a first embodiment of the present invention.

In the present invention, as shown in fig. 1, in the wiring board 1A, a direction in which the pair of first mounting pads 4a and second mounting pads 4b face each other is defined as x, and a direction orthogonal to the direction x is defined as y. In other words, in the embodiment, the longitudinal direction of the chip component 100 of "0603 size" in which the pair of external electrodes (not shown) of the chip component 100 are soldered to the first mounting pad 4a and the second mounting pad 4b, respectively, for surface mounting is set to the x direction, and the width direction is set to the y direction (hereinafter, the same applies to the second embodiment). The size standard of the size of chip component 100 is not particularly limited as long as it is smaller than "1005".

As shown in fig. 1, the wiring board 1A is provided with first and second mounting pads 4a and 4b, first and second circuit patterns 6a and 6b, first and second power detection pads 10a and 10b, first and second lead patterns 12a and 12b, and a solder resist 14 on the surface of a printed circuit board 2.

The printed board 2 is made of, for example, an insulating resin having a thickness of 0.1mm to 1.0 mm. The printed substrate 2 is made of, for example, a glass cloth epoxy resin laminate, a phenol paper substrate, an epoxy paper substrate, a glass/composite substrate, a teflon (registered trademark) substrate, an alumina substrate, a polyimide substrate, or the like.

The first mounting pad 4a and the second mounting pad 4b are square or circular in plan view having a portion electrically connected to the chip component 100. The size of the mounting pad is less than 0.5 mm.

In the present embodiment, since the size standard of the chip component 100 to be mounted on the first mounting pad 4a and the second mounting pad 4b is a small "0603 size", the size of each pad is smaller than 0.5mm square (more specifically, 0.3mm square) in a square pad in plan view, or smaller than 0.5mm (more specifically, 0.3mm) in a circular pad in plan view.

The patterns of the first mounting pads 4a and the second mounting pads 4b are arranged so that the printing deviation is within ± 0.05 to 0.15mm, for example, from the design position.

The mm square refers to the length (unit: mm) of one side of the square pad.

Pad diameter refers to the diameter of a circular pad.

The first mounting pads 4a and the second mounting pads 4b are arranged in parallel with an appropriate interval therebetween.

A solder resist 14 described later is formed between the first mounting pad 4a and the second mounting pad 4 b. Further, between the solder resist 14 and the first mounting pad 4a, a resist gap 5a is formed so as to surround the first mounting pad 4a, and between the solder resist 14 and the second mounting pad 4b, a resist gap 5b is formed so as to surround the second mounting pad 4 b.

The size of the pad for power detection is 0.5mm or more.

In the present embodiment, the first power detection pad 10a and the second power detection pad 10b are formed in a circular shape in a plan view. The first power detection pad 10a and the second power detection pad 10b are set to have diameters of at least 0.5mm or more so as to have areas larger than the first mounting pad 4a and the second mounting pad 4b, respectively. Since the patterns of the first power detection pad 10a and the second power detection pad 10b are formed simultaneously with the patterns of the first mounting pad 4a and the second mounting pad 4b, the print offset design positions are offset by the same amount in the same direction as the first mounting pad 4a and the second mounting pad 4 b. Therefore, the design positions of the patterns of the first power detection pad 10a and the second power detection pad 10b are arranged within ± 0.05 to 0.15mm of the design value.

The first mounting pads 4a and the second mounting pads 4b, and the first power detection pads 10a and the second power detection pads 10b are made of, for example, a metal such as Cu, Au, Pd, or Pt, or an alloy thereof. The first mounting pad 4a and the second mounting pad 4b, and the first power detection pad 10a and the second power detection pad 10b have a thickness of 18 μm or more and 70 μm or less. The first mounting pads 4a and the second mounting pads 4b and the first power detection pads 10a and the second power detection pads 10b are formed by etching a metal layer provided on the surface of the printed circuit board 2. The first mounting pad 4a and the second mounting pad 4b constitute pad portions for mounting an electronic component (chip component 100).

The first mounting pad 4a is electrically connected to the first power detection pad 10a, and the second mounting pad 4b is electrically connected to the second power detection pad 10 b.

The solder resist films 14 for protecting the first mounting pad 4a and the second mounting pad 4b, the first power detection pad 10a and the second power detection pad 10b, and the like from short circuits and the like are formed so that the offset tolerance with respect to the first mounting pad 4a and the second mounting pad 4b and the like is, for example, ± 0.15mm (i.e., the resist gaps 5a and 5b are, for example, within 0.15 mm).

Further, the first lead patterns 12a electrically connecting the first mounting pads 4a and the first power detection pads 10a extend in the y direction toward the outer side of the chip component 100. Similarly, the second lead-out pattern 12b electrically connecting the second mounting pad 4b and the second power detection pad 10b extends in the y direction toward the outer side of the chip component 100.

When two types of manufacturing errors are considered as shown in table 1 below, for example, the lengths of the first lead patterns 12a and the second lead patterns 12b are 0.45mm to 0.6mm, depending on the cumulative result of the manufacturing errors. Here, the ck resist dicing described in the table refers to the width of the solder resist film 14 disposed between the first mounting pad 4a and the second mounting pad 4b and the first power detection pad 10a and the second power detection pad 10 b.

[ Table 1]

ck resist cut	Resist gap	Deviation of printing	Length of lead-out pattern
				0.15mm	0.15mm	0.15mm	0.45mm
0.2mm	0.2mm	0.2mm	0.6mm

The length of the first lead pattern 12a connecting the first mounting pad 4a and the first power detection pad 10a is 0.45mm or more, and the length of the second lead pattern 12b connecting the second mounting pad 4b and the second power detection pad 10b is 0.45mm or more.

With the above configuration, in the wiring board 1A shown in fig. 1, unlike the first mounting pad 4a and the second mounting pad 4b, the first power detection pad 10a and the second power detection pad 10b, which have larger areas than the first mounting pad 4a and the second mounting pad 4b, are provided in the vicinity of the first mounting pad 4a and the second mounting pad 4b, and the probes 16a and 16b are brought into contact with the first power detection pad 10a and the second power detection pad 10b, not with the first mounting pad 4a and the second mounting pad 4 b. Further, even if the positions of the first mounting pads 4a and the second mounting pads 4b are slightly shifted from the normal positions due to manufacturing errors, disconnection of the first circuit patterns 6a and the second circuit patterns 6b can be normally detected by an automatic circuit pattern inspection apparatus.

In the wiring board 1A shown in fig. 1, since the probes 16a and 16b do not press-contact the surfaces of the first mounting pad 4a and the second mounting pad 4b, no depression is generated in the surfaces of the first mounting pad 4a and the second mounting pad 4b, and there is no fear that the chip component 100 will become a surface mounting abnormality.

Second embodiment a second embodiment of the wiring board of the present invention will be described.

A second embodiment of the wiring board of the present invention is a wiring board on which chip components smaller than the chip components 100 described in the first embodiment are mounted.

As shown in fig. 4A, in the wiring board 1B, the first mounting pad 24A and the second mounting pad 24B, the first circuit pattern 26a and the second circuit pattern 26B, the first power detection pad 30a and the second power detection pad 30B, the lead pattern 32, and the solder resist 34 are provided on the surface of the substrate 22.

The size of the mounting pad is less than 0.5 mm.

In the present embodiment, the first mounting pad 24a and the second mounting pad 24b are square or circular. Since the size standard of the mounted chip component 100 is "0603" which is small, the size of each land is smaller than 0.5mm square (more specifically, 0.3mm square) in a square land in a plan view, or smaller than 0.5mm (more specifically, 0.3mm) in a circular land in a plan view.

The patterns of the first mounting pads 24a and the second mounting pads 24b are arranged so that the printing deviation is within ± 0.05 to 0.15mm, for example, from the design position.

The first mounting pads 24a and the second mounting pads 24b are arranged in parallel with an appropriate interval therebetween.

A solder resist 34 described later is formed between the first mounting pad 24a and the second mounting pad 24 b. Further, between the solder resist 34 and the first mounting pad 24a, a resist gap 25a is formed so as to surround the first mounting pad 24 a. Further, between the solder resist 34 and the second mounting pad 24b, a resist gap 25b is formed so as to surround the second mounting pad 24 b.

The size of the pad for power detection is 0.5mm or more.

In the present embodiment, the first power detection pad 30a and the second power detection pad 30b are rectangular. The first power detection pad 30a and the second power detection pad 30b are formed to have larger areas than the first mounting pad 24a and the second mounting pad 24b, respectively. Specifically, for example, the first power detection pad 30a and the second power detection pad 30b are each set to be at least 0.5mm square or more. Since the patterns of the first power detection pads 30a and the second power detection pads 30b are formed simultaneously with the patterns of the first mounting pads 24a and the second mounting pads 24b, the printing deviation is shifted by the same amount from the design position in the same direction as the first mounting pads 24a and the second mounting pads 24 b. Therefore, the design positions of the patterns of the first power detection pad 30a and the second power detection pad 30b are arranged within ± 0.05 to 0.15mm of the design value.

The solder resist films 34 for protecting the first and second mounting pads 24a and 24b, the first and second power detection pads 30a and 30b, and the like from short circuits and the like are formed so that the deviation tolerance with respect to the first and second mounting pads 24a and 24b and the like is, for example, ± 0.15mm (i.e., the resist gaps 25a and 25b are, for example, within 0.15 mm).

Further, the lead pattern 32 electrically connecting the first mounting pad 24a and the first power detection pad 30a extends in the y direction toward the outside of the chip component 100. The second mounting pad 24b and the second power detection pad 30b are directly connected, and the second power detection pad 30b extends in the y direction opposite to the first power detection pad 30a toward the outer side of the chip component 100.

For example, when manufacturing errors in both cases are considered as shown in table 1, the length of the lead pattern 32 is 0.45mm or more and 0.6mm or less according to the cumulative result of the manufacturing errors.

With the above configuration, the wiring board 1B can obtain the same operation and effect as those of the wiring board 1A.

2. Method for manufacturing wiring board

Next, a method for manufacturing a wiring board having the above-described structure will be described by taking the wiring board 1A of the first embodiment shown in fig. 1 as an example.

First, a printed board 2 (hereinafter, also referred to as a copper-clad printed board) made of glass epoxy or the like, to the main surface of which a copper foil is laminated, is prepared. In order to simultaneously form the first mounting pad 4a and the second mounting pad 4b, the first circuit pattern 6a and the second circuit pattern 6b, the first power detection pad 10a and the second power detection pad 10b, the first lead pattern 12a and the second lead pattern 12b, and the like on the surface of the copper-clad printed circuit board 2, a resist ink for etching is applied in a pattern form by using a screen printing method based on polyester, a stainless steel plate, polyarylate, or the like, and is disposed within, for example, ± 0.05 to 0.15mm from the design position.

The method of manufacturing a printed wiring board is a method of forming a pattern by a subtractive method using a laminated board in which a metal layer is formed on the surface of a printed circuit board 2 formed of an insulator, and is a printing method of printing a pattern using a screen and removing the metal layer other than the pattern by etching.

Hereinafter, a method for manufacturing a printed wiring board by a screen printing method will be described with reference to a flowchart of fig. 3.

First, a laminate having a metal layer formed on the surface of a printed board 2 made of an insulator is prepared (step S101).

Next, after performing a pretreatment process such as cleaning or roughening on the prepared laminate, a resist ink is printed on the pattern portion of the metal layer of the laminate using a screen plate (resist ink printing process S102).

Thereafter, the resist ink is cured to form a resist layer (resist layer forming step S103).

Next, the metal layer of the laminate is etched to remove unnecessary portions (portions other than the pattern) (etching step S104).

Next, the resist is stripped to remove the patterned resist (resist removing step S105).

That is, after the etching resist ink is dried, the portion where the etching resist ink is not applied and copper is exposed is etched by the etching solution. Thereafter, the etching resist ink is removed, and the first mounting land 4a and the second mounting land 4b, the first circuit pattern 6a and the second circuit pattern 6b, the first power detection land 10a and the second power detection land 10b, the first lead pattern 12a and the second lead pattern 12b, and the like, which are made of copper, are formed.

Next, solder resist printing is performed on the peripheral area of the pattern portions (the first mounting pad 4a and the second mounting pad 4b, the first circuit pattern 6a and the second circuit pattern 6b, the first power detection pad 10a and the second power detection pad 10b, and the first lead pattern 12a and the second lead pattern 12b) where no soldering is performed, using solder resist ink. Thereafter, the printed solder resist ink is cured to form the solder resist film 14 (solder resist layer forming step S106).

That is, the solder resist 14 is formed by applying the solder resist ink in a pattern by the screen printing method so that the resist gaps 5a and 5b of the first mounting pad 4a and the second mounting pad 4b are arranged within ± 0.15mm, for example, from the design position.

Finally, the outer shape and the hole forming are performed (outer shape and hole forming step S107), and the surface finishing is performed (surface finishing step S108). The surface finishing is to clean the surface of the metal layer and to remove the rust and grease by acid. In this way, the wiring board 1A having the pattern formed on the base material is manufactured.

In addition, other pattern forming methods include a photo printing method and a metal mask printing method. However, the photo printing method has a problem that it takes a long time to manufacture because of many working steps although it has high accuracy. For example, in the case of screen printing, 7 seconds are required for one printing, whereas in the case of photo printing, 30 seconds are required for one printing. Therefore, screen printing is suitable for mass production. In addition, in the case of the metal mask printing method, the metal mask costs 5 to 8 times as much as the screen-printed yarn.

As described above, the wiring board 1A in which the first mounting pads 4a and the second mounting pads 4b and the first power detection pads 10a and the second power detection pads 10b are formed is manufactured.

As described above, the embodiments of the present invention are disclosed in the above description, but the present invention is not limited thereto.

That is, the embodiments described above can be variously modified in mechanism, shape, material, number, position, arrangement, and the like without departing from the scope of the technical idea and the object of the present invention, and these modifications are included in the present invention.

For example, the shape of the power detection pad may be any of a circle, a rectangle, a triangle, an ellipse, and the like. In particular, a circular shape is preferable, which is easily formed in manufacturing.

Description of the symbols

1A, 1B wiring boards;

2. 22 a substrate;

4a, 24a first mounting pad;

4b, 24b second mounting pads;

14. 34 a solder resist film;

5a, 5b, 25a, 25b resist gaps;

6a, 26a first circuit pattern;

6b, 26b second circuit patterns;

10a, 30a first power detection pad;

10b, 30b second power detection pads;

12a first lead-out pattern;

12b a second lead-out pattern;

32 a lead-out pattern;

100 a chip component;

x a pair of mounting pads facing each other;

y is orthogonal to the direction x.