JPH08228066A - Electronic component mounting board and manufacturing method thereof - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a thin electronic component mounting substrate. [Structure] Electronic component mounting board 100 includes resin board 5 ',
A wiring pattern 1'formed on the surface 5'a of the resin substrate 5 ', and chip components 3 and 30 mounted on both surfaces of the wiring pattern 1'are provided. A chip component 30 is connected to the surface 1'a of the wiring pattern 1'by a conductive paint 2. The entire chip component 30 is a resin substrate 5 '.
It is embedded inside. Surface 1'of wiring pattern 1 '
The chip component 3 is mounted on the surface b by the solder 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a board for mounting electronic parts and a method for manufacturing the same, and more particularly to a board for mounting electronic parts such as chip parts and a method for manufacturing the same.

[0002]

2. Description of the Related Art In a conventional electronic component mounting board, when a double-sided mounting board is taken as an example, as shown in FIG.
a and the wiring pattern 1 formed on the back surface 8b
A printed wiring board 8 having 0 and 12 and through holes 9 connecting these wiring patterns 10 and 12 is used, and solder printing is performed on the surface 8a of the printed wiring board 8.
A chip component 3 typified by a chip capacitor or a chip resistor is mounted on the surface 8a and soldered by a reflow furnace.
3 is melted to connect the chip component 3 to the wiring pattern 10, and solder printing is performed on the back surface 8b of the printed wiring board 8.
By mounting the chip component 30 on the back surface 8b and melting the solder 15 by the reflow furnace to connect the chip component 30 and the wiring pattern 12, the electronic component mounting board 100
Was being manufactured.

In a single-sided mounting board, solder printing is performed on the surface of a printed wiring board having a wiring pattern formed on the surface, chip components are mounted on the surface, and the solder is melted by a reflow furnace to form the chip. The electronic component mounting board is manufactured by connecting the component and the wiring pattern.

[0004]

However, in the conventional mounting board, the chip components are mounted on the front surface and the back surface of the printed wiring board, so that the sum of the thickness of the printed wiring board and the height of the chip components is less than or equal to the sum. It was difficult to reduce the thickness of the mounting board.

Further, in order to connect the chip component and the wiring pattern, it is necessary to perform solder printing on the front surface and the back surface of the printed wiring board and then melt the solder in a reflow oven. Particularly, in the case of the double-sided mounting board as shown in FIG. 10, it is necessary to print the solder 13 and the solder 15 on both surfaces 8a and 8b of the printed wiring board 8, respectively. Since it is necessary to use solders having different melting points, and the solder printing and reflow temperatures need to be different between the front surface 8a and the back surface 8b, the manufacturing process is complicated, and further improvement in productivity is desired. It was

Therefore, it is an object of the present invention to provide an electronic component mounting board which is further reduced in thickness.

Another object of the present invention is to provide a method of manufacturing an electronic component mounting board having excellent productivity.

[0008]

According to the present invention, there is provided an electronic component mounting board having an insulating substrate, a wiring pattern provided on the insulating substrate, and an electronic component connected to the wiring pattern. The electronic component is mounted on one main surface of the wiring pattern on the insulating substrate side, and the insulating substrate embeds the electronic component from the one main surface to at least a predetermined height. An electronic component mounting board is provided.

In the electronic component mounting board of the present invention, since the electronic component is mounted on the same side of the wiring pattern as the insulating substrate, the thickness of the electronic component mounting board is the thickness of the electronic component and the insulating substrate. Whichever is thicker, whichever is greater. Therefore, the thickness of the electronic component mounting board can be reduced as compared with the conventional electronic component mounting board whose thickness is determined by the sum of the thickness of the electronic component and the thickness of the insulating substrate.

The insulating substrate may completely embed the electronic component, or the insulating substrate may embed only the lower part of the electronic component and expose the upper part of the electronic component from the insulating substrate. When the electronic component is completely embedded, the electronic component is mechanically protected by the insulating substrate, and the upper part of the electronic component is not exposed, so that the insulating substrate on which the electronic component is mounted can be easily handled. The rigidity of the insulating substrate is also increased. On the other hand, if only the lower part of the electronic component is embedded and the upper part of the electronic component is exposed from the insulating substrate, heat dissipation from the electronic component becomes easy.

As the insulating substrate in the present invention, a resin substrate made of an insulating resin such as an epoxy resin is preferably used.

In the present invention, a double-sided mounting type electronic component mounting substrate can be realized by further mounting electronic components on the main surface of the wiring pattern opposite to the insulating substrate. Also in this case, the thickness of the entire electronic component mounting board is smaller than that of the conventional electronic component mounting board in which electronic components are mounted on both surfaces of the printed wiring board. Then, in the conventional electronic component mounting board on which electronic components are mounted on both sides of the printed wiring board, through holes for connecting the wiring patterns on both sides of the printed wiring board are required, but in the present invention, Since electronic components are mounted on both sides of the same wiring pattern, it is not necessary to form through holes.

The electronic component mounted on one main surface of the wiring pattern on the side of the insulating substrate is preferably connected to the wiring pattern by a conductive paint, and the main surface of the wiring pattern on the side opposite to the side of the insulating substrate. The electronic component mounted on the wiring pattern is preferably mounted on the wiring pattern by soldering.

Further, according to the present invention, a step of connecting an electronic component to one main surface of a conductive flat plate with a conductive paint, and a resin for embedding the electronic component to at least a predetermined height from the one main surface. There is provided a method for manufacturing an electronic component mounting board, comprising: a step of forming a substrate on the one main surface of the flat plate; and a step of patterning the flat plate to form a wiring pattern.

In the present invention, the electronic component is connected to the main surface of the conductive flat plate by the conductive paint, and the resin substrate for embedding the electronic component to at least a predetermined height is provided on the main surface of the conductive flat plate. Since it is formed as described above, the step of mounting an electronic component by solder printing and solder reflow as in the related art is unnecessary. In addition, the thickness of the electronic component mounting board formed in this manner is determined by the thickness of the electronic component or the thickness of the resin substrate, whichever is greater.
As a result, the thickness of the electronic component mounting board can be reduced as compared with the conventional electronic component mounting board whose thickness is determined by the sum of the thickness of the electronic component and the thickness of the printed wiring board.

The conductive paint used in the present invention is preferably a conductive paint containing silver powder, copper powder or the like.

The resin for the resin substrate used in the present invention is preferably an epoxy resin or the like.

Furthermore, as the conductive flat plate used in the present invention, a copper plate and a copper foil are preferably used.

In the present invention, an electronic component may be further mounted on the main surface of the wiring pattern formed by patterning a flat plate on the side opposite to the resin substrate. By doing so, a double-sided mounting type electronic component mounting board can be realized. Also in this case, the thickness of the entire electronic component mounting board is smaller than that of the conventional electronic component mounting board in which electronic components are mounted on both surfaces of the printed wiring board. When an electronic component is further mounted on the main surface of the wiring pattern opposite to the resin substrate, preferably, the electronic component is mounted after solder printing, and then the solder is melted by a reflow oven to melt the electronic component. Connect parts and wiring patterns.
In the present invention, since the electronic components are connected by the conductive paint on the main surface of the wiring pattern on the resin substrate side,
In this soldering, it is not necessary to use two kinds of solders having different melting points as in the case of the conventional printed wiring board.

Further, in the conventional method of mounting electronic components on both sides of the printed wiring board, it is necessary to form through holes for connecting the wiring patterns on both sides of the printed wiring board. Since electronic components are mounted on both main surfaces of the same wiring pattern, it is not necessary to form through holes.

When an electronic component is not further mounted on the main surface of the wiring pattern formed by patterning a flat plate on the side opposite to the resin substrate, the main surface on the side opposite to this wiring pattern is formed of an insulating film or the like. You can also cover it with. In particular,
If the resist pattern used as a mask when patterning the flat plate is not peeled off, the resist pattern peeling step can be omitted and the wiring pattern can be protected by the resist.

[0022]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of an electronic component mounting board of the present invention. The electronic component mounting board 100 of the present embodiment is a double-sided mounting board, and includes a resin board 5 ′ made of epoxy resin and a wiring made of a copper plate or copper foil formed on the surface 5a ′ of the resin board 5 ′. Pattern 1 '
And chip parts 3 and 30 mounted on both surfaces of the wiring pattern 1 ', respectively. The surface 1'a of the wiring pattern 1'is in contact with the surface 5a 'of the resin substrate 5'.
The chip component 30 is connected to the surface 1'a of the wiring pattern 1'by the conductive paint 2 containing silver powder and copper powder. The entire chip component 30 is embedded inside the resin substrate 5 ′. The chip component 3 is mounted by solder 11 on the surface 1'b of the wiring pattern 1 '.

In the electronic component mounting board 100 of this embodiment, the chip components 3 and 30 are mounted on both sides of the wiring pattern 1 ', and the mounting density is the both sides using the conventional printed wiring board shown in FIG. It is equivalent to the mounting board. Moreover, since the entire chip component 30 is completely embedded in the resin substrate 5 ′, the electronic component mounting substrate 10 of the present embodiment.
0 thickness is the sum of 'the thickness t ₁ of the wiring pattern 1' resin substrate 5 and the thickness t ₂ and thickness t ₃ of the chip component 3. Therefore, in the electronic component mounting board 100 of the present embodiment, the thickness of the chip component 30 is irrelevant, and the thickness of the electronic component mounting board 100 is correspondingly reduced. Also,
Thus, if the chip component 30 is completely embedded in the resin substrate 5 ', not only the chip component 30 is mechanically protected by the resin substrate 5', but the upper portion of the chip component 30 is not exposed. Therefore, it becomes easy to handle the resin substrate 5'on which the chip component 30 is mounted. Furthermore, since the resin substrate 5'is formed thick until the chip component 30 is completely embedded, the rigidity of the resin substrate 5'is also increased.

Next, the electronic component mounting board 100 of this embodiment
A manufacturing method of the above will be described with reference to FIGS.

First, as shown in FIG. 2, a copper plate or copper foil 1 is prepared, and a conductive coating material 2 containing silver powder and copper powder is selectively printed on the surface 1a of the copper plate or copper foil 1 to mount the component mounting portion. To create. Next, as shown in FIG.
0 is mounted on the conductive paint 2, and the conductive paint 2 is cured by heating in an oven or the like to connect the chip component 30 to the surface 1a of the copper plate or copper foil 1.

Next, as shown in FIG.
A copper plate or copper foil 1 on which is mounted is housed in a resin forming mold 4. After that, as shown in FIG. 5, an insulating resin 5 made of epoxy is injected into the resin forming mold 4 and heated and cured.

Next, as shown in FIG. 6, the resin substrate 5'formed by curing the resin 5 is taken out from the mold 4, inverted and coated with a resist 6 on the surface 1b of the copper plate or copper foil 1. And heat to cure. After that, as shown in FIG. 7, the wiring pattern portion and the lead terminals are exposed by using a predetermined mask and then developed (hereinafter, the wiring pattern portion and the lead terminals are collectively referred to as a wiring pattern). The resist in the other regions is selectively removed to form a resist pattern 6 '.

Next, the copper plate or copper foil 1 is patterned by selectively etching the copper plate or copper foil 1 using the resist pattern 6'as a mask, and then the resist pattern 6'is peeled off, as shown in FIG. As shown, the wiring pattern 1'is formed on the surface 5'a of the resin substrate 5 '.

Next, as shown in FIG. 1, solder printing is performed on the surface 1b 'of the wiring pattern 1', the chip component 3 is mounted, and the solder 11 is melted by a reflow oven to form the wiring pattern of the chip component 3 on the wiring pattern 1 '. Mounted on the surface 1b 'of 1',
The electronic component mounting board 100 is manufactured.

In this embodiment, since the conductive paint 2 is used to connect the chip component 30 to the wiring pattern 1 ', the conventional step of mounting the chip component 30 by solder printing and solder reflow is required. It becomes unnecessary.

Further, when the chip component 3 is mounted on the surface 1'b of the wiring pattern 1 ', solder is used, but in the present embodiment, the chip component 30 is connected to the wiring pattern 1'by conductive paint. Therefore, it is not necessary to use two kinds of solders having different melting points as in the case of the conventional printed wiring board.

Further, in this embodiment, the chip components 30 and 3 are mounted on the surfaces 1'a and 1'b on both sides of the same wiring pattern 1 ', respectively. There is no need to provide through holes as in the case.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, as shown in FIG.
The chip component 30 may be made thinner than the surface 1'a of the wiring pattern 1'to a predetermined height. In this case, the thickness of the electronic component mounting board 100 is the sum of the thickness t ₄ of the chip component 30 and the thickness t ₂ and thickness t ₃ of the chip component 3 of the wiring pattern 1 '. Therefore, since the thickness of the resin substrate 5'is not relevant, the thickness of the electronic component mounting substrate 100 is correspondingly reduced. It should be noted that exposing the upper portion of the chip component 30 in this manner facilitates heat dissipation from the chip component 30. Such a resin substrate 5'can be formed by injecting the resin 5 up to the broken line in the step shown in FIG.

Further, in the above embodiments, the chip components 3 and 30 have been described as an example, but the electronic components mounted on the electronic component mounting board of the present invention are not necessarily limited to the chip components. Packaged parts, resin molded parts, bare chips, etc. can also be mounted.

In the above, the wiring pattern 1 '
The double-sided mounting board in which the chip components 3 and 30 are mounted on both sides of the wiring board has been described.
It can also be applied to a single-sided mounting board in which the chip component 30 is mounted on one surface 1'a. In this case, since the thickness of the mounting board is determined by the thickness of the resin board 5'or the thickness of the chip component 30, whichever is larger, the thickness of the electronic component mounting board becomes thinner. In order to manufacture such a single-sided mounting type electronic component mounting board,
The electronic component 30 is mounted on the resin substrate 5'as shown in FIG.
7 and FIG. 8, the copper plate or copper foil 1 is selectively etched by using the resist pattern 6 ′ as a mask to pattern the copper plate or copper foil 1 to form the wiring pattern 1 ′. May be formed on the surface 5'a of the resin substrate 5 '. In this case, since the electronic component is not mounted on the surface 1'b of the wiring pattern 1 ', the resist pattern 6'is not necessarily peeled off. Thus, if the resist pattern 6'is not peeled off, not only the peeling step can be omitted, but also the wiring pattern 1'can be protected by the resist.

[0037]

According to the present invention, since the electronic component is mounted on the same side as the insulating substrate with respect to the wiring pattern, the thickness of the electronic component mounting substrate can be reduced while maintaining the mounting density.

Further, in the present invention, since the electronic component can be further mounted on the main surface of the wiring pattern opposite to the insulating substrate, the thickness of the double-sided mounting type electronic component mounting substrate can be reduced. In this case, since electronic parts are mounted on both surfaces of the wiring pattern, there is no need to form through holes in the insulating substrate, and productivity is improved.

Further, according to the present invention, an electronic component is connected to the main surface of the conductive flat plate by a conductive paint, and a resin substrate for embedding the electronic component to at least a predetermined height is used as the main surface of the conductive flat plate. Since it is formed on the surface, the step of mounting the electronic component on the one main surface by the conventional solder printing and solder reflow becomes unnecessary, and the productivity and the economical efficiency are improved. Also, by mounting an electronic component on the main surface of the wiring pattern formed by patterning a flat plate on the side opposite to the resin substrate by soldering, a double-sided mounting type electronic component mounting board can be realized. In the case of attachment, it is not necessary to use solders having different melting points, and productivity and economic efficiency are improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an electronic component mounting board according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating the method of manufacturing the electronic component mounting board according to the embodiment of the present invention.

FIG. 3 is a sectional view for explaining the method for manufacturing the electronic component mounting board according to the embodiment of the present invention.

FIG. 4 is a sectional view for explaining the method for manufacturing the electronic component mounting board according to the embodiment of the present invention.

FIG. 5 is a sectional view for explaining the method for manufacturing the electronic component mounting board according to the embodiment of the present invention.

FIG. 6 is a cross-sectional view for explaining the method for manufacturing the electronic component mounting board according to the embodiment of the present invention.

FIG. 7 is a sectional view for explaining the method for manufacturing the electronic component mounting board according to the embodiment of the present invention.

FIG. 8 is a sectional view for explaining the method for manufacturing the electronic component mounting board according to the embodiment of the present invention.

FIG. 9 is a cross-sectional view showing an electronic component mounting board of another embodiment of the present invention.

FIG. 10 is a cross-sectional view for explaining a conventional electronic component mounting board and a method for manufacturing the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Copper plate or copper foil 1a, 1b, 1'a, 1'b ... Copper plate or copper foil surface 1 '... Wiring pattern 2 ... Conductive paint 3,30 ... Chip component 4 ... Resin forming mold 5 ... Resin 5 '... Resin substrate 5'a ... Resin substrate surface 6 ... Resist 6' ... Resist pattern 8 ... Printed wiring board 10, 12 ... Wiring pattern 11, 13, 15 ... Solder 100 ... Electronic component mounting board

Claims (2)

[Claims] 1. An electronic component mounting board having an insulating substrate, a wiring pattern provided on the insulating substrate, and an electronic component connected to the wiring pattern, wherein the electronic component has the wiring pattern. An electronic component mounting substrate, which is mounted on one main surface of the electronic component mounting board, wherein the insulating substrate embeds the electronic component to at least a predetermined height from the one main surface. 2. A step of connecting an electronic component to one main surface of a conductive flat plate with a conductive paint, and a resin substrate for embedding the electronic component from the one main surface to at least a predetermined height. A method of manufacturing an electronic component mounting board, comprising: a step of forming on one main surface; and a step of patterning the flat plate to form a wiring pattern.