JP2001189552A - Board mounted with part, method for manufacturing board mounted with electronic part device and part, and method for mounting chip part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a board mounted with a part, a method for manufacturing a board mounted with electronic part devices and parts, and a method for mounting a chip part, capable of preventing a solder metal component from oozing out. SOLUTION: Metal films 51-71, 52-72 are deposited on the mounting surface of a substrate 1. Protective films 12-13 are attached to the mounting surface of the substrate 1 to bury a space produced around the metal films 51-71, 52-72. Solder metal films 91, 92 are deposited on the surfaces of the metal films 51-71, 52-72 to make the almost the whole surface a flat surface nearly parallel to the mounting surface of the substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a component mounting board, an electronic component device, a method of manufacturing a component mounting board, and a method of mounting a chip component.

[0002]

2. Description of the Related Art When an electronic component, particularly a chip-shaped electronic component, is soldered to a component mounting board, conventionally, as disclosed in Japanese Patent Application Laid-Open No. H11-121915, for example, A component mounting board is prepared by applying a solder paste to the land. The solder paste is formed by means such as printing, and the components are placed on the solder paste formed on the component mounting board, and then soldered by passing through a reflow furnace. .

Meanwhile, in order to cope with high-density mounting of various electronic devices, mounted components have been miniaturized, and the pitch between components has been narrowed. Under such conditions, when components are soldered to a component mounting board by a conventional soldering method, various problems that have not conventionally been required to be considered arise. One of them is the bleeding of the solder paste, which causes a short circuit phenomenon.

[0004] Before passing through a reflow oven, the solder paste is not solidified. Therefore, the solder paste may seep out of the land due to the mounting pressure of the chip component. When such a solder paste seepage phenomenon occurs, a short circuit occurs between the terminal electrodes of adjacent components at a reduced arrangement interval or between lands on the component mounting board due to a solder metal component in the seepaged solder paste. As a result, a failure due to a short circuit occurs.

[0005] There is also known a leveler method for flattening the surface of a solder paste applied on a land before mounting a chip component. However, the surface of the solder paste is not flattened over the entire surface, but an inclined surface is generated at the peripheral portion. Therefore, there is a problem that the chip component is inclined according to the inclined surface, and finally, the chip component is soldered in an inclined state.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a component mounting board, an electronic component device, a method of manufacturing a component mounting board, and a method of mounting a chip component, which can prevent leaching of a solder metal component. is there.

Another object of the present invention is to provide a component mounting board, an electronic component device, a method of manufacturing a component mounting board, and a method of mounting a chip component on which a chip component can be mounted without being inclined.

[0008]

In order to solve the above-mentioned problems, the present invention discloses a component mounting board, an electronic component device, a method of manufacturing the component mounting board, and a method of mounting a chip component.

A component mounting board according to the present invention includes at least one metal film, a protective film, and a solder metal film. The metal film is attached on at least one substrate surface. The protective film is attached on the substrate surface and fills a space created around the metal film. The solder metal film is attached to the surface of the metal film, and substantially the entire surface is a flat surface substantially parallel to the substrate surface.

An electronic component device according to the present invention includes the above-described component mounting board and at least one chip component.
The chip component is soldered on the component mounting board. When soldering chip components, use the metal film provided on the component mounting board and the laminated film of the solder metal film as lands, apply flux to the surface of the solder metal film, and position the chip component terminal electrodes on it And
Pass through a reflow oven.

Here, in the component mounting board according to the present invention, since the solder metal film is used, the chip component is mounted on the solid solder metal film. Therefore, even if the solder metal film is subjected to the mounting pressure of the chip component before being passed through the reflow furnace, the solder metal film does not seep out of the laminated film of the metal film and the solder metal film constituting the land. Therefore, between terminal electrodes of adjacent components at a narrower arrangement interval or between lands on a component mounting board, etc.
No short circuit is caused by the exuded solder metal component, and no failure occurs due to a short circuit. Flux is applied between the solder metal film and the chip component, but the oozing of the flux does not cause a short circuit.

Further, since the entire surface of the solder metal film is a flat surface substantially parallel to the substrate surface,
The chip component is soldered substantially parallel to the board surface. Furthermore, in the component mounting board according to the present invention, since the protective film is attached on one surface of the electric insulating plate and fills a space generated around the metal film, the side surface of the metal film that is liable to peel or oxidize is removed. It can be covered and protected by a protective film.

[0013] The method of manufacturing a component mounting board according to the present invention comprises:
It includes the following steps.

First, in at least one substrate surface,
A metal film is attached, and a protective film is formed on the substrate surface to fill a space generated around the metal film.

Next, a resist film is formed on the surface of the protective film so as to surround the metal film. Next, a solder metal film is attached on the metal film surrounded by the resist film.

Next, the surface of the solder metal film is flattened. After that, the resist film is removed from above the protective film.

In the above step, the step of forming a resist film on the surface of the protective film so as to surround the metal film can be performed by a step of forming a resist film by a printing method or a photolithography step.

When a photolithography step is adopted, a resist is applied to the surface of the metal film and the protective film, the resist is exposed and developed, and the resist existing on the metal film is removed.

In the mounting method of the chip component according to the present invention, the chip component is soldered on the component mounting substrate using the component mounting substrate obtained by the above-described method of manufacturing the component mounting substrate according to the present invention.

[0020]

FIG. 1 is a partial sectional view of a component mounting board according to the present invention. The illustrated component mounting board 1 includes two metal films (51, 61, 71),
(52, 62, 72), protective films 11 to 13, and solder metal films 91 and 92.

Metal films (51-71), (52-72)
Are attached to one surface (mounting surface) of the substrate 1 to form a land. The illustrated metal films (51-71), (52
To 72) are two, but the number is arbitrary. The number may be only one or two or more. In the illustrated embodiment, the metal films (51 to 71) are made of C
u film 51, a Ni film 61, and an Au film 71 are sequentially laminated, and the metal films (52 to 72) are Cu films 5
2. It has a laminated film structure in which a Ni film 62 and an Au film 72 are sequentially laminated. In addition, a different metal film or a laminated film structure may be adopted.

The protective films 11 to 13 are attached on the mounting surface of the substrate 1 and fill the spaces generated around the metal films (51 to 71) and (52 to 72). Protective films 11 to 13
Can be constituted by a resist that is frequently used in this type of component mounting board.

The solder metal films 91 and 92 are made of a metal film (51).
To 71) and (52 to 72), and almost the entire surface is a flat surface substantially parallel to one surface of the substrate 1.

<Electronic Component Device> FIG. 2 is a partial sectional view showing a soldering process of the electronic component device according to the present invention, and FIG.
1 is a partial sectional view of an electronic component device according to the present invention. The illustrated electronic component device is a component mounting board 1 shown in FIG.
And at least one chip component 4. The chip component 4 is soldered on the component mounting board 1.
2 and 3 show only one chip component 4, but the number is arbitrary. The chip components 4 are various electronic components.

In soldering the chip part 4,
As shown in FIG. 2, the metal films (51 to 71) and (52 to 72) provided on the component mounting board 1 and the solder metal film 9 are provided.
The laminated films 1 and 92 are used as lands, and the solder metal films 91 and 9 are used as lands.
2 are coated with fluxes 93 and 94 by printing or the like, and the terminal electrodes 41 of the chip component 4 are coated thereon.
Position 42. Then, in the state shown in FIG. 2, a reflow furnace or the like is passed. Thereby, an electronic component device as shown in FIG. 3 is obtained.

Since the component mounting board 1 uses the solder metal films 91 and 92 as shown in FIG.
The chip component 4 is mounted on the solid solder metal films 91 and 92. For this reason, even if the solder metal films 91 and 92 receive the mounting pressure of the chip component 4 before passing through the reflow furnace, the solder metal component will be replaced by the metal films (51 to 71) and (52) constituting the lands. 72) and the solder metal films 91 and 92 do not ooze out of the laminated film. Accordingly, between the terminal electrodes of adjacent components or between lands on the component mounting board or the like at the narrowed arrangement interval is not short-circuited by the exuded solder metal component, and a failure due to a circuit short-circuit is generated. Absent. Fluxes 93 and 94 are applied between the solder metal films 91 and 92 and the chip component 4 (see FIG. 2).
The seepage of 3,94 does not cause a short circuit.

FIG. 4 shows a distance (μ) between adjacent components when the chip component 4 is soldered to the component mounting board 1 shown in FIG.
FIG. 8 is a diagram showing a relationship between m) and an adjacent component short-circuit rate (%). In the figure, a curve L11 indicates the adjacent component short-circuit rate (%) according to the related art in which the chip component 4 is soldered using a solder paste. A curve L12 indicates an adjacent component short-circuit rate (%) when the chip component 4 is soldered using the component mounting board 1 according to the present invention.
Adjacent parts spacing is 300μm, 200μm, 150μ
m and 100 μm.

As shown in the figure, in the conventional soldering method using a solder paste, the distance between adjacent components is 200 μm.
If it is smaller than 150 μm or 100 μm, a short circuit between adjacent components occurs. This means that in the conventional soldering method using a solder paste, the distance between adjacent components is 20
It means that it cannot be smaller than 0 μm.

On the other hand, the component mounting board 1 according to the present invention
When the chip component 4 is soldered by using
As shown in FIG. 2, no short circuit occurs between adjacent components even when the interval between adjacent components is set to 150 μm or even to 100 μm. This data shows that, according to the present invention, at least the distance between adjacent components can be reduced to 100 μm.

Further, since the entire surface of the solder metal films 91 and 92 is a flat surface substantially parallel to the mounting surface of the substrate 1, the chip component 4 is , Soldered almost parallel. Further, in the component mounting board 1 according to the present invention, the protective films 11 to 13 are adhered on the mounting surface of the board 1, and the metal films (51 to 71), (5)
2-72)
Metal films (51-71) that are liable to cause peeling, oxidation, etc., (52
To 72) can be covered and protected by the protective films 11 to 13.

As the fluxes 93 and 94, a general flux containing rosin as a main component can be used. Rosin contains carboxylic acids such as abietic acid and levovimaric acid.
The oxide film on the metal surface to be soldered is removed.

Various additives such as a solvent, a plasticizer or a thixotropic agent may be blended for the purpose of improving printability and obtaining temporary fixing strength. For example, JP-A-11-1219
As disclosed in Japanese Patent Publication No. 15, a type of flux whose viscosity is adjusted by adding alcohol may be used.

As another flux, an RMA (halogen-free) flux specified in a mill standard can be used. In the case of this flux, a washing step of the flux or the like after the reflow is omitted.

Further, as another example of the fluxes 93 and 94, an adhesive flux containing an adhesive resin and a curing agent can be used. Since this adhesive flux contains an adhesive resin and a curing agent, after soldering, the adhesive resin can function as an adhesive for fixing the component mounting board and the component. For this reason, it is possible to prevent the components from peeling or falling off due to impact or thermal stress, and to improve the reliability of the solder joint. This point is significantly different from the conventional rosin flux having no bonding function after soldering.

Moreover, by using the adhesive flux, a sufficient fixing strength can be ensured even if the solder has no fillet portion. For this reason, it is not necessary to provide a region for generating a fillet portion in the metal films (51 to 71) and (52 to 72) formed on the component mounting board 1, and it is possible to improve the mounting density. Becomes

In the adhesive flux, as the adhesive resin, a resin exhibiting a high adhesive strength is selected from a large number of resin materials according to the temperature, and can be used as the adhesive resin. Therefore, after the component 4 was soldered to the first side of the component mounting board of the double-sided mounting type using adhesive flux, the reflow furnace was passed through the second side of the component mounting board 1 using normal eutectic solder. Even in such a case, the component 4 mounted on the first surface does not cause a problem such as shifting, a Manhattan phenomenon (component standing phenomenon), or falling off. Of course, an adhesive flux can be used in both the first and second soldering processes.

The adhesive flux can be in the form of a liquid or a paste. Such a flux can be easily applied to the component mounting substrate 1 by means such as printing, dispenser application, spraying, and brushing.

In the adhesive flux, a preferred adhesive resin is a thermosetting resin. Specific examples of the thermosetting resin include at least one selected from an epoxy resin, a phenol resin, a polyimide resin, a silicone resin, a modified resin, and an acrylic resin.
The types and amounts of the exemplified resin materials can be selected according to the bonding temperature range, the target film hardness, and the like.

The curing agent may be any as long as it cures the adhesive resin. Preferably, it contains a carboxylic acid. The curing agent containing a carboxylic acid has not only a hardening action on the thermosetting resin but also a flux action for removing an oxide film on the surface of the metal to be soldered.

The adhesive flux may contain a solvent, a plasticizer or a thixotropic agent. The solvent is added to adjust the curing temperature and the curing speed of the adhesive resin and to adjust the viscosity according to the application form. Plasticizers and thixotropic agents are also added to adjust the viscosity depending on the form of application. The amounts of the solvent, plasticizer, thixotropic agent and the like are selected according to the purpose of use.

The adhesive flux may be in the form of microcapsules enclosing an adhesive resin, an organic acid, a carboxylic acid, a solvent or a curing agent for providing a reducing action.

<Method of Manufacturing Component Mounting Board> FIGS. 5 to 19
Shows a manufacturing process of the component mounting board 1 according to the present invention.

First, a metal film (51) is provided on the mounting surface of the substrate 1.
To 71) and (52 to 72) are adhered, and a protective film is formed on the mounting surface of the substrate 1 so as to fill a space generated around the metal films (51 to 71) and (52 to 72). This process is a process mainly including a photolithography step, which is already known as a land forming means, and will be described with reference to FIGS.

Referring to FIG. 5, an appropriate metal film 5 such as copper is formed on the mounting surface of the substrate 1. The substrate 1 having such a metal film 5 is well known as a copper-clad substrate.

Next, as shown in FIG. 6, a resist film R1 is applied to the entire surface of the metal film 5. The resist film R1 can be formed by means such as a curtain coating method or a spin coating method. Further, the resist film R1 can be used by selecting from various commercially available resist materials.

Next, as shown in FIG. 7, a resist film R1 is formed.
A photomask M1 having a predetermined mask pattern is set on the substrate and exposed. Then, development is performed by a conventionally known means to form a specified resist mask R11 as shown in FIG. Thereafter, as shown in FIG. 9, portions of the metal film 5 that are not covered with the resist mask R11 are removed by means such as chemical etching. As a result, the metal film 51 having a land pattern to be obtained is formed at a predetermined position.

Next, as shown in FIG. 10, a resist film R2 is applied to the entire surface of the substrate 1 including the metal film 51.
As shown in FIG. 11, a photomask M2 is set on the resist film R2 and exposed. The photomask M2 is positioned (in the case of a positive resist) so that the cut pattern is positioned on the metal film 51.

Thereafter, the resist on the exposed metal film 51 is removed by development. Portions of the resist film R2 that are not exposed remain. As a result, the metal film 51 is attached to the mounting surface of the substrate 1,
A space generated around the metal film 51 is formed by a resist film R2.
The substrate surface film structure buried with is obtained. After this, the metal film 51
A Ni film, an Au film or the like is adhered on the substrate by plating or other means. As a result, as shown in FIG. 12, the metal films 61 and 71 are adhered on the mounting surface of the substrate 1, and a space generated around the metal films (51 to 71) is formed on the mounting surface of the substrate 1 by resist. A substrate surface film structure filled with the protection films 11 and 12 by the film R2 is obtained.

In the method of manufacturing a component mounting board according to the present invention, the processes shown in FIGS.

This process includes a step of forming a resist film on the surfaces of the protective films 11 and 12 so as to surround the metal films (51 to 71). This step can be performed by two different processes. One is a photolithography process and the other is a printing method. First, a case where a photolithography process is employed will be described.

In this case, as shown in FIG. 13, a photosensitive resist film R3 is applied to the surfaces of the metal films (51 to 71) and the protective films 11 and 12. The resist film R3 may be negative or positive. The embodiment shows a case where a negative type ultraviolet curable resist is used. The resist film R3 is formed by applying a curtain coating method, a spin coating method, or the like.
It is applied to a thickness of about μm.

Next, as shown in FIG.
3 and a photomask M3 was placed on it, and using an exposure machine,
The resist film R3 is exposed. Exposure is limited to exposure in the ultraviolet region. The photomask M3 is made of a metal film 51 to
A pattern corresponding to a region corresponding to the upper region of 71 is not exposed.

Next, development is performed. Thereby, as shown in FIG. 15, the resist film R3 is removed in a portion corresponding to the region above the unexposed metal films 51 to 71, and the metal films 51 to 71 appear.

Next, as shown in FIG.
In the trace of resist removal on 71, metal films 51 to 71
A solder metal film 91 is attached on the substrate. Solder metal film 9
1 is formed so as to obtain a final thickness of about 35 to 60 μm. The solder metal film 91 can be formed by a solder leveler method. The solder metal film 91 is made of Sn,
It can be selected from Cu, Ag, Sb, Pb, Zn, In and Bi. To obtain a Pb-free solder paste, the solder powder is composed of a solder powder other than Pb.

Next, as shown in FIG. 17, the surface of the solder metal film 91 is flattened by using, for example, a pressing means LV so as to be at substantially the same plane position as the surface of the resist film R31. Thereby, as shown in FIG. 18, the surface of the solder metal film 91 is planarized so as to be substantially in the same plane position as the surface of the resist film R31.

Thereafter, the resist film R31 remaining on the protective films 11 to 13 is removed. The removal of the resist film R31 depends on the resist material.
% NaOH solution can be used.

Thus, the component mounting board 1 according to the present invention is obtained as shown in FIG. The thickness of the solder metal film 91 is set to about 35 to 60 μm. In the case of the present invention, the thickness of the solder metal film 91 depends on the flattening process (FIG. 1).
In 7) and 18), it can be controlled by the thickness of the resist film 91. In addition, the surface of the solder metal film 91 has extremely high flatness (smoothness), and rises with the periphery being almost vertical.

When the printing method is adopted, as shown in FIG. 12, metal films 61 and 71 are adhered on the mounting surface of the substrate 1 and the metal films (51 to 71) are formed on the mounting surface of the substrate 1. The space created around the protective film 1 is formed by the resist film R2.
13 and 14 are omitted and the metal film 51 is filled in the process shown in FIG.
A resist film R31 is formed around -71 by means such as screen printing. As the resist film R31,
It is preferable to use a thermosetting, solvent stripping, or NaOH stripping resist. In the example, the resist film R31 was screen-printed using a NaOH strippable resist.

Thereafter, the processes shown in FIGS. 16 to 19 are executed. In the process of FIG. 19, the resist film R31 can be stripped using a solvent and a NaOH solution.

<Mounting Method of Chip Components> This mounting method has already been described with reference to FIGS. The chip component 4 is soldered onto the component mounting board 1 using the component mounting board 1 obtained by the above-described component mounting board manufacturing method.

[0061]

As described above, according to the present invention, the following effects can be obtained. (A) It is possible to provide a component mounting board, an electronic component device, a method of manufacturing a component mounting board, and a method of mounting a chip component, which can prevent oozing of a solder metal component. (B) It is possible to provide a component mounting board, an electronic component device, a method of manufacturing a component mounting board, and a method of mounting a chip component, which can mount a chip component without tilting.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a component mounting board according to the present invention.

FIG. 2 is a partial sectional view showing a soldering process of the electronic component device according to the present invention.

FIG. 3 is a partial sectional view of the electronic component device according to the present invention.

FIG. 4 is a diagram showing a relationship between a distance (μm) between adjacent components and a short-circuit ratio (%) of adjacent components when chip components are soldered to the component mounting board according to the present invention.

FIG. 5 is a view showing a manufacturing process 1 of the component mounting board according to the present invention.
FIG.

FIG. 6 illustrates a process after the process illustrated in FIG. 5;

FIG. 7 illustrates a process after the process illustrated in FIG. 6;

FIG. 8 illustrates a process after the process illustrated in FIG. 7;

FIG. 9 illustrates a process after the process illustrated in FIG. 8;

FIG. 10 illustrates a process after the process illustrated in FIG. 9;

FIG. 11 illustrates a process after the process illustrated in FIG. 10;

FIG. 12 illustrates a process after the process illustrated in FIG. 11;

FIG. 13 illustrates a process after the process illustrated in FIG. 12;

FIG. 14 illustrates a process after the process illustrated in FIG. 13;

FIG. 15 illustrates a process after the process illustrated in FIG. 14;

FIG. 16 illustrates a process after the process illustrated in FIG. 15;

FIG. 17 illustrates a process after the process illustrated in FIG. 16;

FIG. 18 illustrates a process after the process illustrated in FIG. 17;

FIG. 19 illustrates a process after the process illustrated in FIG. 18;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Component mounting board 4 Chip component 81, 82 Solder paste film

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[Procedure amendment]

[Submission date] February 21, 2000 (200.2.2
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 2

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 10

[Procedure amendment 3]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 11

Continued on the front page F term (reference) 4E351 BB31 CC11 DD04 DD05 DD08 DD10 DD12 DD13 DD24 DD52 DD54 GG15 5E314 AA27 BB02 BB11 CC06 DD07 FF01 GG22 5E319 AA03 AC15 BB01 BB05 CC33 CD15 CD21 CD26 CD29 GG05

Claims (12)

[Claims] At least one metal film, a protective film,
A component mounting board including a solder metal film, wherein the metal film is attached to at least one substrate surface, and the protective film is attached on the substrate surface, and is formed around the metal film. A component mounting board which fills a space, wherein the solder metal film is attached to the surface of the metal film, and a substantially entire surface is a flat surface substantially parallel to the substrate surface. 2. The component mounting board according to claim 1, wherein said solder metal film or said solder powder is Sn, C
A component mounting substrate including at least one selected from u, Ag, Sb, Pb, Zn, In, or Bi. 3. An electronic component device including a component mounting board and at least one chip component, wherein the component mounting board is the one described in claim 1 or 2, wherein the chip component is provided. Is an electronic component device soldered on the component mounting board. 4. A method for manufacturing a component mounting board, comprising: attaching a metal film to at least one of the board surfaces;
Forming a protective film on the substrate surface to fill a space generated around the metal film; forming a resist film on the surface of the protective film so as to surround the metal film; A method for manufacturing a component mounting board, comprising: attaching a solder metal film on a metal film; planarizing a surface of the solder metal film; and removing the resist film from above the protective film. 5. The method according to claim 4, wherein the step of forming the resist film on the surface of the protective film so as to surround the metal film includes forming the resist film by a coating method. A method for manufacturing a component mounting board including steps. 6. The method according to claim 4, wherein the step of forming the resist film on the surface of the protective film so as to surround the metal film comprises: forming a resist on the metal film and the protective film. A method for manufacturing a component mounting board, comprising: applying the resist on the surface of a film, exposing and developing the resist, and removing the resist existing on the metal film. 7. The method according to claim 4, wherein the solder metal film is formed of Sn, Cu, Ag, Sb, Pb,
A method of manufacturing a component mounting board including at least one selected from Zn, In, and Bi. 8. A method for mounting a chip component on a component mounting board, wherein the component mounting board is manufactured by the method according to claim 4; And a method for mounting a chip component, comprising a step of soldering the chip component. 9. The method for mounting a chip component according to claim 8, comprising a step of applying an adhesive flux containing an adhesive resin and a curing agent before soldering the chip component. How to mount chip components. 10. The method for mounting a chip component according to claim 9, wherein the adhesive resin of the adhesive flux contains a thermosetting resin. 11. The mounting method of a chip component according to claim 10, wherein the thermosetting resin is an epoxy resin, a phenol resin,
A method of mounting a chip component including at least one selected from a polyimide resin, a silicon resin, a modified resin, and an acrylic resin. 12. The method for mounting a chip component according to claim 9, wherein the curing agent includes a carboxylic acid.