JP2013004656A - Printed wiring board, electronic component mounting structure, and method of manufacturing electronic component mounting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a printed wiring board that can prevent a chip standing of an electronic component even when an insulating layer is coated by being shifted from a regular position; an electronic component mounting structure configured to mount an electronic component on the printed wiring board via solder; and a method of manufacturing the electronic component mounting structure.SOLUTION: A printed wiring board 10 has a rectangular opening 13a in an insulating layer 13, and mounts an electronic component 20 via a solder 30 on a pair of conductor wires 12a exposed to the opening 13a. The opening 13a is disposed in a constant-width parallel region R of the pair of conductor wires 12a in which line widths A and B have the same width and are parallel to each other. A dimension of the opening 13a in a width direction thereof exceeds a dimension of the pair of conductor wires 12a in their width direction. Both outer end surfaces 12a-2 of the pair of conductor wires 12a are located inside compared to both inner end surfaces 13-1 of the opening 13a in the width direction thereof.

Description

  The present invention relates to a printed wiring board in which an electronic component is mounted on a pair of conductor wirings exposed in an opening of an insulating layer via solder, and an electronic device in which the electronic component is mounted on the printed wiring board via solder. The present invention relates to a component mounting structure and a method for manufacturing the electronic component mounting structure.

In a printed wiring board disposed inside an electronic device, an electronic component (a so-called chip component) having a pair of electrodes is mounted on a pair of conductor wirings exposed at the opening of the insulating layer via solder. Some form an electronic component mounting structure.
As a prior art showing such a printed wiring board, for example, there is Patent Document 1 below.

JP 2005-203616 A

The above Patent Document 1 is an invention related to a chip component mounting structure and a chip component mounting method, and provides a chip component mounting structure and a chip component mounting method capable of suppressing the generation of solder balls even in the soldering operation of a very small chip component. There is a merit that can be done.
In a printed wiring board on which an electronic component having a pair of electrodes is mounted via solder on a pair of conductor wirings exposed in the opening of such an insulating layer, it is applied to the upper surface of the pair of conductor wirings. If there is a difference in the area of the contact portion between the solder and the electrode of the electronic component, the surface tension of the solder melted during solder reflow causes a difference in the surface of the electronic component, so-called chip standing occurs. It was.
In such a chip standing, the size (area) of the upper surface of the conductor wiring exposed in the opening is formed by forming an insulating layer made of a solder resist or the like having an opening shifted from a normal position. One reason is that the pair of conductor wirings do not have the same size, and the amount of solder applied to the upper surface of the conductor wiring differs between the pair of conductor wirings.
However, the above-mentioned Patent Document 1 has a problem that there is no structure that can prevent the chip standing due to the insulating layer being shifted from the normal position, and there is no such description or suggestion. there were.
Here, “chip standing” means a phenomenon in which an electronic component rises and only one side is soldered.

  Therefore, the present invention solves the above-described conventional problems, and even when the insulating layer is formed with a deviation from a normal position, a printed wiring board that can prevent the chip of an electronic component from standing, and the printed wiring board via solder. It is an object of the present invention to provide an electronic component mounting structure in which electronic components are mounted and a method for manufacturing the electronic component mounting structure.

  The printed wiring board of the present invention is a printed wiring board having a rectangular opening in an insulating layer, and mounting electronic components on a pair of conductor wirings exposed in the opening via solder. The portion is provided in a parallel region having the same line width and parallel to each other in the pair of conductor wirings, and the width direction dimension of the opening exceeds the width direction dimension of the pair of conductor wirings. The first feature is that both the outer end faces of the pair of conductor wirings are inside the both inner end faces in the width direction of the opening.

  According to the first feature of the present invention, the printed wiring board includes a rectangular opening in the insulating layer, and the electronic component is mounted on the pair of conductor wirings exposed in the opening via solder. In the printed wiring board, the opening is provided in a parallel region having the same width and parallel to each other in the pair of conductor wirings, and the widthwise dimension of the opening is the pair. In the manufacturing process of the printed wiring board, since both outer end faces of the pair of conductor wirings are on the inner side than both inner end faces in the width direction of the opening, Even when the insulating layer is formed with a deviation from the normal position, the size (area) of the conductor wiring exposed in the opening of the insulating layer is the same size (area) in the pair of conductor wirings. be able to. Therefore, when an electronic component is mounted on the pair of conductor wirings exposed at the openings of the insulating layer via solder, the amount of solder applied to the conductor wiring can be made the same amount by the pair of conductor wirings. . Therefore, in the pair of conductor wirings, there is no difference in the area of the contact portion between the applied solder and the electrode of the electronic component, and it is possible to prevent the difference in the surface tension of the molten solder during the solder reflow. it can. Therefore, a printed wiring board capable of preventing the electronic component from standing is provided.

  In the printed wiring board of the present invention, in addition to the first feature of the present invention, the electronic component is a rectangular parallelepiped, has electrodes on both ends of the surface, and has a side length of 0.4 mm in plan view. And the distance between the pair of conductor wirings constituting the same-width parallel region is 0.1 mm to 0.2 mm. It has the characteristics of

  According to the second feature of the present invention, in addition to the operational effects of the first feature of the present invention, the electronic component comprises a rectangular parallelepiped, has electrodes on both ends of the surface, and has one side in a plan view. The distance between the pair of conductor wirings constituting the same width parallel region is 0.1 mm to 0.2 mm while being a 0402 type having a length of 0.4 mm and a length of the other side of 0.2 mm. Therefore, even when a minute electronic component is mounted, it is possible to provide a printed wiring board that can effectively prevent the electronic component from standing. Therefore, it is possible to provide a printed wiring board for mounting a minute electronic component with high electrical and mechanical connection reliability.

  Further, in the printed wiring board of the present invention, in addition to the second feature of the present invention, a line width of the conductor wiring constituting the same width parallel region is 0.15 mm to 0.2 mm. It has the characteristics of

  According to the third feature of the present invention, in addition to the function and effect of the second feature of the present invention, a line width of the conductor wiring constituting the same-width parallel region is 0.15 mm to 0.2 mm. Therefore, the dimension from the end face in the width direction of the electronic component to the outer end face of the conductor wiring can be shortened. Therefore, in the solder reflow process when mounting the electronic component on the printed wiring board, the force for pulling down the electronic component can be reduced. Therefore, even when a 0402 type minute electronic component is mounted on the printed wiring board, the printed wiring board can be more effectively prevented from standing of the chip of the electronic component. Therefore, it is possible to provide a printed wiring board for mounting a minute electronic component with higher electrical and mechanical connection reliability.

  Further, the electronic component mounting structure of the present invention has a pair of conductor wirings exposed to the opening of the printed wiring board according to any one of the first to third aspects of the present invention via solder. A fourth feature is that an electronic component including the electrode is mounted.

  According to the fourth aspect of the present invention, the electronic component mounting structure of the present invention is a pair exposed at the opening of the printed wiring board according to any one of the first to third aspects of the present invention. Since an electronic component including a pair of electrodes is mounted on the conductor wiring of the electronic component, the electronic component can be prevented from standing up and has high electrical and mechanical connection reliability. It can be a mounting structure. Moreover, even if the electronic component to be mounted is very small, the chip standing of the electronic component can be effectively prevented.

  An electronic component mounting structure manufacturing method according to the present invention is the electronic component mounting structure manufacturing method according to claim 4, wherein a printed wiring board including a pair of conductor wirings exposed in the opening of the insulating layer is provided. A step of forming, a step of applying solder to the pair of conductor wires exposed in the opening, and a step of mounting electronic components on the pair of conductor wires exposed in the opening via the solder The step of forming the printed wiring board includes at least a step of forming a parallel region of the same width in which the line widths of the pair of conductor wires are the same width and parallel to each other, and the shape of the opening portion. A rectangular shape in which the widthwise dimension of the opening exceeds the widthwise dimension of the pair of conductor wirings, and both inner end faces in the widthwise direction of the opening are outside the outer end faces of the pair of conductor wirings. And a step of forming as a fifth feature There.

According to the fifth aspect of the present invention, an electronic component mounting structure manufacturing method according to claim 4 is a method of manufacturing an electronic component mounting structure according to claim 4, wherein the pair of exposed electronic component mounting structures is exposed at the opening of the insulating layer. A step of forming a printed wiring board having conductor wiring, a step of applying solder to the pair of conductor wirings exposed in the opening, and a pair of conductor wirings exposed in the opening via solder Mounting the electronic component at least, and forming the printed wiring board includes forming a parallel region of the same width in which the line widths of the pair of conductor wirings are the same and parallel to each other. The shape of the opening is such that the widthwise dimension of the opening exceeds the widthwise dimension of the pair of conductor wirings, and both inner end faces in the widthwise direction of the opening are both outer sides of the pair of conductor wirings. A step of forming a rectangular shape outside the end surface. Thus, in the step of forming the printed wiring board, the size of the pair of conductor wirings exposed in the opening of the insulating layer is the same even when the insulating layer is formed with a deviation from the normal position. It can be. Therefore, the amount of solder applied to the conductor wiring can be made the same by a pair of conductor wiring. Therefore, there is no difference in the contact area between the applied (printed) solder and the electrode of the electronic component in a pair of conductor wirings, and a difference in the surface tension of the molten solder during solder reflow is prevented. can do. Accordingly, it is possible to prevent the electronic component from standing up and to manufacture an electronic component mounting structure with high electrical and mechanical connection reliability.
Moreover, even if the electronic component to be mounted is a minute electronic component, it is possible to provide a method for manufacturing an electronic component mounting structure that can effectively prevent chip standing of the electronic component.

According to the printed wiring board of the present invention, it is possible to provide a printed wiring board that can prevent chip standing of an electronic component even when the insulating layer is formed with a deviation from a normal position, and is electrically and mechanically It can be set as the printed wiring board for electronic component mounting with high connection reliability. Further, even when a minute electronic component is mounted, it is possible to provide a printed wiring board for mounting an electronic component that can effectively prevent the electronic component from standing.
Further, according to the electronic component mounting structure of the present invention, even when the insulating layer is formed with a deviation from the normal position, it is possible to prevent the electronic component from standing, and the electronic component having high electrical and mechanical connection reliability. A component mounting structure can be adopted. Moreover, even if the electronic component to be mounted is a minute electronic component, an electronic component mounting structure that can effectively prevent the electronic component from standing on the chip can be obtained.
Further, according to the method for manufacturing an electronic component mounting structure of the present invention, even when the insulating layer is formed with a deviation from a normal position, it is possible to prevent the electronic component from standing, and electrical and mechanical connection reliability is achieved. A high electronic component mounting structure can be manufactured. Moreover, even if the electronic component to be mounted is a minute electronic component, it is possible to provide a method for manufacturing an electronic component mounting structure that can effectively prevent chip standing of the electronic component.

It is a top view which shows the principal part of the electronic component mounting structure which concerns on embodiment of this invention. It is sectional drawing in the aa line direction of FIG. BRIEF DESCRIPTION OF THE DRAWINGS It is a top view which shows the principal part of the electronic component mounting structure which concerns on embodiment of this invention, (a) is a figure which shows the case where the insulating layer provided with an opening part is shifted | deviated from the normal position and formed in the horizontal direction, (b) ) Is a diagram showing a case where an insulating layer having an opening is formed by being shifted from the normal position in the horizontal direction and the vertical direction. It is sectional drawing which simplifies and shows the manufacturing method of the printed wiring board and electronic component mounting structure which concern on embodiment of this invention. It is sectional drawing which simplifies and shows the manufacturing method of the electronic component mounting structure which concerns on embodiment of this invention. It is a figure which shows the principal part of the conventional printed wiring board and an electronic component mounting structure, (a) is a top view which shows the principal part of the conventional printed wiring board, (b) shows the principal part of the conventional electronic component mounting structure. It is sectional drawing.

  With reference to the following drawings, a printed wiring board according to an embodiment of the present invention, an electronic component mounting structure in which an electronic component is mounted on the printed wiring board via solder, and a method for manufacturing the electronic component mounting structure will be described. In order to understand the present invention. However, the following description is an embodiment of the present invention, and does not limit the contents described in the claims.

  First, with reference to FIGS. 1-3, the printed wiring board 10 and the electronic component mounting structure 1 which concern on embodiment of this invention are demonstrated.

As shown in FIGS. 1 and 2, the printed wiring board 10 according to the embodiment of the present invention is a so-called single-sided flexible printed wiring board having a conductive layer 12 only on one side of the base material layer 11, and the insulating layer 13. This is a printed wiring board constituting the electronic component mounting structure 1 by mounting the electronic component 20 on the conductor wiring 12a exposed to the opening 13a via the solder 30.
As shown in FIG. 2, the printed wiring board 10 includes a base material layer 11, a conductive layer 12, and an insulating layer 13.

The base material layer 11 serves as a base for the printed wiring board 10 and is formed of an insulating resin film.
As a resin film, what consists of a resin material excellent in the softness | flexibility is used. For example, any film may be used as long as it is normally used as a resin film for forming a substrate layer of a printed wiring board, such as a polyimide film or a polyester film.
In particular, those having high heat resistance in addition to flexibility are desirable. For example, polyamide resin films, polyimide resin films such as polyimide and polyamideimide, and polyethylene naphthalate can be preferably used.
Further, as the heat resistant resin, any resin may be used as long as it is usually used as the heat resistant resin for forming the base layer of the printed wiring board, such as polyimide resin and epoxy resin.
The thickness of the base material layer 11 is desirably about 5 μm to 50 μm.

The conductive layer 12 is a layer that is laminated on the front side of the base material layer 11 and constitutes the conductor wiring 12a of the printed wiring board 10, terminals (not shown), and the like.
In this embodiment, as shown in FIG. 2, a conductor wiring 12a is formed on a part of the conductive layer 12, and a pair of conductors is formed from an opening 13a formed by opening a part of an insulating layer 13 described later. The land 12a-1 is formed by exposing the wiring 12a.
Here, “land” means a region where the solder 30 is applied (printed) in the conductor wiring 12a.
Further, in the present embodiment, as shown in part in FIG. 1, the same-width parallel region R in which the line widths A and B of the pair of conductor wirings 12a are the same width and are parallel to each other is provided.
As shown in FIG. 1, both the outer end faces 12a-2 in the width direction of the pair of conductor wirings 12a are inside the both inner end faces 13a-1 in the width direction of the opening 13a.
Here, the “width direction of the opening 13a” means the same direction as the width direction of the conductor wiring 12a.

The conductive layer 12 is formed by laminating a conductive metal foil on the base material layer 11 using plating (so-called additive method), or etching a conductive metal foil pre-laminated on the base material layer 11 (so-called subtractive). It can be formed using a known forming method such as (Method).
Moreover, copper (Cu) can be used as the conductive metal foil. Of course, it is not limited to copper (Cu), and any material can be used as long as it is normally used as a conductive metal foil for forming a conductive layer of a printed wiring board.
The line width A and the line width B of the pair of conductor wirings 12a are preferably about 0.15 mm to 0.2 mm, particularly when a 0402 type electronic component is used as the electronic component 20.
The distance C between the pair of conductor wirings 12a is preferably about 0.1 mm to 0.2 mm, more preferably 0.15 mm, particularly when a 0402 type electronic component is used as the electronic component 20. It is desirable to set the degree.
Here, “0402 type” is a rectangular parallelepiped electronic component having electrodes on both ends of the surface, one side (horizontal) length D in a plan view shown in FIG. It means an electronic component having a side (vertical) length E of 0.2 mm.
The thickness of the conductive layer 12 is preferably about 8 μm to 35 μm.

The insulating layer 13 is a layer for ensuring insulation of the printed wiring board 10.
The insulating layer 13 is made of a solder resist, a coverlay, or the like, and can be formed using a known forming method. In this embodiment, the insulating layer 13 is formed by covering the base material layer 11 and the conductive layer 12 with a dry film type solder resist. Of course, the present invention is not limited to such a configuration, and a development type liquid solder resist or a coverlay may be used as the insulating layer 13.
In the present embodiment, as shown in FIGS. 1 and 2, a rectangular opening 13 a for exposing the conductive layer 12 is provided in the insulating layer 13.
As shown in FIG. 1, the opening 13a is provided in the same width parallel region R, and the width direction dimension exceeds the width direction dimension of the pair of conductor wirings 12a.
More specifically, the dimension (length F) of one side (lateral) of the opening 13a is such that the line width A and the line width B of the pair of conductor wirings 12a and the distance C between the pair of conductor wirings 12a. It is set as the structure longer than the dimension (length) which added. Further, as shown in FIG. 1, both the inner end faces 13a-1 in the width direction of the opening 13a are configured to be outside the both outer end faces 12a-2 of the pair of conductor wirings 12a.
The length G of the other side (vertical) of the opening 13a shown in FIG. 1 is preferably about 0.2 mm to 0.3 mm, particularly when a 0402 type electronic component is used as the electronic component 20.
1 and 2, the length H from the outer end surface 12a-2 of the conductor wiring 12a to the inner end surface 13a-1 of the opening 13a when the insulating layer 13 is formed at a regular position is the opening In an unillustrated mounting machine (for example, a laminating machine for a dry film type solder resist, a screen printing machine for a developing type liquid solder resist, etc.) for forming an insulating layer 13 having 13a on the base layer 11 and the conductive layer 12 It is necessary to be not less than the maximum value of the alignment accuracy (the maximum value of the deviation width of the opening 13a). More specifically, in the case where a 0402 type electronic component is used as the electronic component 20, it is desirable that the thickness be approximately 0.65 μm.
The thickness of the insulating layer 13 is desirably about 5 μm to 80 μm.

The electronic component 20 is a surface mount type (so-called chip type) electronic component having a pair of electrodes on the surface, such as a chip-type ceramic capacitor, for example. As shown in FIG. The electrode 22 is electrically and mechanically connected to the pair of conductor wirings 12a, so that the electronic component mounting structure 1 is formed by being mounted on the printed wiring board 10.
As shown in FIGS. 1 and 2, the electronic component 20 includes an element body 21 and an electrode 22.

The element body 21 forms the main body of the electronic component 20 and is formed of a known magnetic material or nonmagnetic material that constitutes the element body of a so-called chip-type electronic component.
As the magnetic material, ferrite or the like can be used.
As the nonmagnetic material, aluminum oxide (alumina) or the like can be used.

The electrodes 22 are made of a conductive metal, and are external electrodes that are provided at both ends of the element body 21 in a non-contact manner.
Note that copper, gold, silver, or the like can be used as the conductive metal.

The solder 30 is for electrically and mechanically connecting the conductor wiring 12a and the electronic component 20 (electrode 22).
The solder 30 is applied (printed) on the land 12a-1 using a printing machine such as a screen printing machine.

The printed wiring board 10 according to the embodiment of the present invention having the above configuration and the electronic component mounting structure 1 formed by mounting the electronic component 20 on the printed wiring board 10 have the following effects.
The width parallel region R is provided, a rectangular opening 13a is provided in the width parallel region R, and the width direction dimension of the opening 13a exceeds the width direction dimension of the pair of conductor wirings 12a. A configuration in which both outer end faces 12a-2 of the pair of conductor wirings 12a are on the inner side of both inner end faces 13-1 in the width direction of the opening 13a (a pair of inner end faces 13-1 in the width direction in the opening 13a is a pair. In the manufacturing process of the printed wiring board 10, the insulating layer 13 is formed (covered) with a deviation from the normal position. Even if it exists, the magnitude | size of the conductor wiring 12a exposed to the opening part 13a of the insulating layer 13 can be made into the same magnitude | size with a pair of conductor wiring 12a.
More specifically, when the insulating layer 13 is formed (covered) in a state where the opening 13a is shifted to the left side by the length J from the normal position indicated by the one-dot chain line in FIG. Even when the insulating layer 13 is formed (covered) in a state where it is shifted to the right by the length K from the normal position indicated by the alternate long and short dash line in FIG. The size (area) of the land 12a-1 can be made the same by a pair of (left and right) conductor wirings 12a. Therefore, the same amount of solder 30 can be applied (printed) to the left and right lands 12a-1. Therefore, in the pair of lands 12a-1, there is no difference in the area of the contact part between the applied (printed) solder 30 and the electrode 22 of the electronic component 20, and the surface tension of the solder 30 melted during solder reflow is reduced. It is possible to prevent the difference from occurring. That is, the force for pulling down the electronic component 20 (indicated by the white arrow in FIG. 2) can be made the same by the left and right solders 30.
Therefore, even when the insulating layer 13 having the opening 13a is formed (covered) with a deviation from the regular position, the chip standing of the electronic component 20 can be effectively prevented, and electrical and mechanical The printed wiring board 10 and the electronic component mounting structure 1 for mounting electronic components with high connection reliability can be obtained.
Further, even if the electronic component 20 to be mounted is a very small electronic component such as the 0402 type, it is possible to effectively prevent the electronic component 20 from standing up, and a minute electronic device having high electrical and mechanical connection reliability. The printed circuit board 10 for mounting components and the electronic component mounting structure 1 formed by mounting minute electronic components can be obtained.

On the other hand, in the conventional printed wiring board 100 and the electronic component mounting structure 2 in which the electronic component 200 is mounted on the printed wiring board 100 via the solder 300, as shown by a one-dot chain line in FIG. In addition, there is a configuration in which a rectangular opening 130a is provided in the same width parallel region R and the width dimension of the opening 130a does not exceed the width dimension of the pair of conductor wirings 120a. More specifically, as shown by a one-dot chain line in FIG. 6A, the length M of one side (lateral) of the opening 130a is determined by the line width N and the line width P of the pair of conductor wirings 120a, There is a configuration in which the length is shorter than the length obtained by adding the interval Q between the pair of conductor wirings 120a.
In such a configuration, the insulating layer 130 is formed in a state in which the opening 130a is shifted to the left by the length T from the normal position indicated by the one-dot chain line in FIG. In the case of covering, the size (area) of the land 120a-1 indicated by the oblique line is different in size (area) between the pair of (left and right) conductor wirings 120a. More specifically, the area of the left land 120a-1 is larger than the area of the right land 120a-1.
Therefore, the amount of solder 300 coated (printed) on the land 120a-1 is different between the left and right.
Therefore, in the pair of lands 120a-1, there is a difference in the area of the contact portion between the applied (printed) solder 300 and the electrode 220 of the electronic component 200, and there is a difference in the surface tension of the solder 300 melted during the solder reflow. . That is, the force (indicated by a white arrow in FIG. 6B) for pulling down the electronic component 200 has different magnitudes between the left and right solders 300.
Therefore, when the insulating layer 130 including the opening 130a is formed (covered) with a deviation from a normal position, there is a problem that the chip of the electronic component 200 is generated.
In the conventional printed wiring board 100 and the electronic component mounting structure 2, the same members and functions as those of the printed wiring board 10 and the electronic component mounting structure 1 described above have the same two-digit number and alphabet. A detailed description will be omitted.

  Therefore, the printed wiring board 10 according to the embodiment of the present invention and the electronic component mounting structure 1 in which the electronic component 20 is mounted on the printed wiring board 10 via the solder 30 make the insulating layer provided with the opening 13a. Even when 13 is formed (covered) with a deviation from the normal position, the printed wiring board 10 and the electronic component mounting structure 1 that can effectively prevent the electronic component 20 from standing up to the chip can be obtained. .

  Next, referring to FIG. 1, FIG. 4, and FIG. 5, an electronic component mounting structure 1 in which the electronic component 20 is mounted on the printed wiring board 10 and the printed wiring board 10 according to the embodiment of the present invention via the solder 30. The manufacturing method will be described.

First, referring to FIG. 4A, the conductive layer 12 is laminated on the base material layer 11, and the conductor wiring 12 a and terminals (not shown) are formed at predetermined positions of the conductive layer 12. At this time, as shown in FIG. 1, the same width parallel region R in which the line widths A and B of the pair of conductor wirings 12a are the same width and parallel to each other is formed.
When a 0402 type electronic component is used as the electronic component 20, the line width A and the line width B of the conductor wiring 12a are set to about 0.15 mm to 0.2 mm, and the distance C between the pair of conductor wirings 12a. Is preferably about 0.1 mm to 0.2 mm, more preferably about 0.15 mm.
Next, referring to FIG. 4B, the insulating layer 13 having the opening 13a is aligned on the base material layer 11 and the conductive layer 12 by using a mounting machine (lamination machine) (not shown) and covered. Let
At this time, as shown in FIGS. 1 and 4B, the opening 13a is formed in a rectangular shape whose width dimension exceeds the width dimension of the pair of conductor wirings 12a. More specifically, the length F of one side (horizontal) is longer than the length obtained by adding the line width A and line width B of the pair of conductor wirings 12a and the interval C between the pair of conductor wirings 12a. Form as a shape. Further, the opening 13a is arranged in the same width parallel region R, and as shown in FIG. 1, both inner end faces 13-1 in the width direction of the opening 13a are more than both outer end faces 12a-2 of the pair of conductor wirings 12a. The insulating layer 13 is covered on the base material layer 11 and the conductive layer 12 so as to be outside.
Through the above steps, the printed wiring board 10 according to the embodiment of the present invention is manufactured.
Next, referring to FIG. 4 (c), the conductor wiring in which the cream solder 30a is exposed to the opening 13a using the squeegee 50 of a screen printing machine (not shown) in a state where the printed wiring board 10 is covered with the metal mask 40. Application (printing) is performed on the upper surface (land 12a-1) of 12a.
Next, referring to FIG. 5A, the electronic component 20 having the electrodes 22 at both ends of the surface of the element body 21 is mounted on the printed wiring board 10 via the melted cream solder 30a by a solder reflow process. More specifically, the pair of conductor wirings 12a and the pair of electrodes 22 are electrically and mechanically connected to each other via cream solder 30a.
Through the above steps, the electronic component mounting structure 1 according to the embodiment of the present invention is manufactured as shown in FIG.

The manufacturing method of the printed wiring board 10 and the electronic component mounting structure 1 according to the embodiment of the present invention having such a configuration has the following effects.
In the present embodiment, a parallel parallel region R is provided, a rectangular opening 13a is provided in the parallel parallel region R, and the width in the opening 13a is the same as that in the pair of conductor wirings 12a. And the insulating layer on the base material layer 11 and the conductive layer 12 so that both the inner end faces 13-1 in the width direction of the opening 13a are outside the both outer end faces 12a-2 of the pair of conductor wirings 12a. 13 is covered. With this configuration, even when the insulating layer 13 is formed (covered) with a deviation from the normal position, the upper surface of the conductor wiring 12a exposed to the opening 13a of the insulating layer 13 (land 12a- The size (area) of 1) can be made the same by the pair of conductor wirings 12a.
Thereby, the same amount of cream solder 30a can be applied (printed) to the pair of lands 12a-1 exposed in the opening 13a, and thus the cream solder applied (printed) on the pair of lands 12a-1. There is no difference in the area of the contact portion between 30a and the electrode 22 of the electronic component 20, and a difference in the surface tension of the cream solder 30a melted during solder reflow can be prevented. That is, the force for pulling down the electronic component 20 can be set to the same magnitude by the cream solder 30a provided in the pair of conductor wirings 12a.
Therefore, even when the insulating layer 13 having the opening 13a is formed (covered) with a deviation from a normal position, the printed wiring board 10 and the electronic component mounting structure 1 that can prevent the electronic component 20 from standing up. Can be manufactured.
Further, even if the electronic component 20 to be mounted is a minute electronic component such as the 0402 type, the chip standing of the electronic component 20 can be effectively prevented, and the minute electronic device having high electrical and mechanical connection reliability. It can be set as the manufacturing method of the electronic component mounting structure 1 which mounts the printed wiring board 10 for component mounting, and a minute electronic component.

  In the present embodiment, the printed wiring board 10 is configured to use a so-called single-sided flexible printed wiring board that includes the conductive layer 12 only on one side of the base material layer 11, but is not necessarily limited to such a configuration. The base layer 11 may have a configuration using a so-called double-sided flexible printed wiring board having conductive layers 12 on both sides, or a configuration using another printed wiring board such as a rigid wiring board.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to this Example.

  As common conditions for the mounting test, the distance C between the pair of conductor wirings 12a shown in FIG. 1 is 0.15 mm, the length G of the other side (vertical) of the opening 13a is 0.2 mm, and the insulating layer 13 is regular. The length H from the outer end surface 12 a-2 in the width direction of the conductor wiring 12 a to the inner end surface 13 a-1 in the width direction of the opening 13 a is 65 μm and is mounted via the solder 30. The electronic component to be used is a 0402 type, and as a comparison condition, the line width A and the line width B of the conductor wiring 12a are (1) 0.15 mm, (2) 0.175 mm, (3) 0.2 mm, (4) The incidence rate of chip standing was evaluated for the electronic component mounting structure according to the embodiment of the present invention for every 520 samples at 0.225 mm. The results are shown in Table 1.

From the results shown in Table 1, in the electronic component mounting structure 1 according to the embodiment of the present invention, when the electronic component to be mounted is of the 0402 type, the conductor 20 extends from the end face 20a in the width direction of the electronic component 20 shown in FIGS. It can be seen that the shorter the length V of the wiring 12a to the outer end face 12a-2, the lower the occurrence rate of the chip standing.
This is because the shorter the length V from the end surface 20a of the electronic component 20 to the outer end surface 12a-2 of the conductor wiring 12a is, the more the molten solder becomes on the end surface 20a of the electronic component 20 having higher wettability in the solder reflow process. This is because the amount that rises in a fillet shape can be suppressed, and the force for pulling down the electronic component 20 can be reduced.
Therefore, when the printed wiring board 10 and the electronic component mounting structure 1 according to the embodiment of the present invention are manufactured under the common conditions described above, the line width A and the line width B of the conductor wiring 12a shown in FIGS. The printed wiring board 10 and the electronic component mounting capable of further preventing the electronic component 20 (0402 type minute electronic component) from standing by being about 15 mm to 0.2 mm, more preferably about 0.15 mm. It can be set as the manufacturing method of the structure 1 and the electronic component mounting structure 1. FIG.

  According to the present invention, even when the insulating layer is formed on the printed wiring board so as to deviate from the normal position, the electronic component can be prevented from standing up, so that the electronic component is mounted on the printed wiring board via solder. Industrial applicability is high in the field of electronic components having a mounting structure.

DESCRIPTION OF SYMBOLS 1 Electronic component mounting structure 2 Electronic component mounting structure 10 Printed wiring board 11 Base material layer 12 Conductive layer 12a Conductor wiring 12a-1 Land 12a-2 Outer end surface 13 Insulating layer 13a Opening portion 13a-1 Inner end surface 20 Electronic component 20a End surface 21 Element 22 Electrode 30 Solder 40 Metal Mask 50 Squeegee 100 Printed Wiring Board 110 Base Material Layer 120 Conductive Layer 120a Conductor Wiring 120a-1 Land 120a-2 Outer End Surface 130 Insulating Layer 130a Opening 200 Electronic Component 210 Element 220 Electrode 300 Solder A Line Width B Line Width C Interval D Length E Length F Length G Length H Length J Length K Length L Length M Length N Line Width P Line Width Q Interval R Same Width Parallel Region T Length U length V length

Claims (5)

  A printed wiring board having a rectangular opening in an insulating layer, and mounting electronic components on a pair of conductor wiring exposed in the opening via solder, wherein the opening is the pair of conductor wiring Are provided in the same width parallel region having the same line width and parallel to each other, and the width direction dimension of the opening exceeds the width direction dimension of the pair of conductor wirings, and A printed wiring board characterized in that both outer end faces of the conductor wiring are on the inner side than both inner end faces in the width direction of the opening.   The electronic component is a 0402 type having a rectangular parallelepiped, having electrodes on both ends of the surface, and having a side length of 0.4 mm and a side length of 0.2 mm in plan view. The printed wiring board according to claim 1, wherein an interval between the pair of conductor wirings constituting the width parallel region is 0.1 mm to 0.2 mm.   The printed wiring board according to claim 2, wherein a line width of the conductor wiring constituting the parallel region of the same width is 0.15 mm to 0.2 mm.   The electronic component mounting which mounts an electronic component provided with a pair of electrodes via a solder on a pair of conductor wiring exposed in the opening part of the printed wiring board of any one of Claims 1-3 Construction.   5. The method of manufacturing an electronic component mounting structure according to claim 4, wherein a step of forming a printed wiring board including a pair of conductor wirings exposed in the opening of the insulating layer, and 1 exposed in the opening. At least a step of applying solder to a pair of conductor wirings and a step of mounting electronic components on the pair of conductor wirings exposed in the openings via the solder, and forming the printed wiring board Forming the same width parallel region where the line widths of the pair of conductor wirings are the same width and parallel to each other, the shape of the opening, and the width direction dimension of the opening is the pair of conductors. Forming a rectangular shape that exceeds the widthwise dimension of the wiring and has both inner end faces in the widthwise direction of the opening outside the both outer end faces of the pair of conductor wirings. Manufacturing method of component mounting structure.

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