JP2709840B2 - Substrate for mounting electronic components - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electronic component mounting substrate having a resin sealing frame around an electronic component mounting portion and having excellent product reliability and durability.

(Prior art)

As shown in FIGS. 6 and 7, conventionally, an electronic component mounting substrate (hereinafter simply referred to as a substrate) 9 has a resin sealing frame 91 on an insulating substrate 90 and an input / output pin It is known that there are a number of standing.

That is, the conventional substrate 9 includes an electronic component mounting portion 92 formed on the insulating substrate 90 and a plurality of conductor circuits formed so as to extend on the insulating substrate 90 from the periphery of the electronic component mounting portion 92.
93 and a through hole 94 formed at one end of the conductor circuit 93.
And a resin sealing frame 91 mounted on the upper surface of the conductor circuit 93 so as to surround the electronic component mounting portion 92. Therefore, the upper portion of the through hole 94 is closed by the resin sealing frame 91 as shown in FIG.

An input / output pin 95 is fitted in a lower part of the through hole 94 and is soldered to the through hole 94. On the other hand, the resin sealing frame 91 is bonded to the through hole 94 of the substrate 9 at the upper portion thereof via an adhesive layer 96, for example, an adhesive sheet. Therefore, the through hole
94 has a cavity A sealed at the center from the upper part. In addition, air stays in the cavity A, and the flux or the like used at the time of soldering the input / output pins 95 remains.

[Problem to be solved]

However, the conventional substrate 9 has the following problems. That is, when the input / output pins 95 are soldered to the through holes 94 on the substrate 9, the resin sealing frame 91 has already been bonded to the upper portions of the through holes 94. Therefore, even if the substrate 9 is immersed in a molten solder bath (not shown), the solder does not sufficiently penetrate and fill the through holes 94. As a result, the electrical connection between the input / output pins 95 and the inner wall of the through hole 94 becomes insufficient, which causes a reduction in product reliability.

Further, when the substrate 9 is washed after the solder bonding, a solvent such as Freon cannot enter the through hole 94, and the flux in the cavity remains.

Thus, after a long time, the residual flux causes corrosion and deterioration of the through-hole 94, the input / output pin 95, and the like, which causes the durability of the substrate 9 to decrease.

On the other hand, the air staying in the cavity A expands due to heating during wire bonding and resin sealing, and the insulating substrate 90
And the resin sealing frame 91 may be peeled off.

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems, and an object of the present invention is to provide an electronic component mounting board which is excellent in product reliability and durability and excellent in electrical connection between a through hole and an input / output pin. Is what you do.

[Solutions to solve the problem]

The present invention is directed to an electronic component mounting portion formed on an insulating substrate, a plurality of conductor circuits formed on the insulating substrate from the periphery of the electronic component mounting portion, and formed at one end of the conductor circuit. A through hole, a resin sealing frame adhesively bonded to the upper surface of the conductor circuit so as to surround the electronic component mounting portion, and an input / output from the side opposite to the resin sealing frame with respect to the through hole. In the electronic component mounting board having a pin head inserted therein, the resin sealing frame has an opening formed of a cutout, a through hole, or the like at a portion corresponding to a through hole in the insulating substrate. When the resin sealing frame is bonded and bonded to the insulating substrate, the opening in the resin sealing frame is formed so as not to block the upper part of the through hole, and the inner wall of the through hole and the inner wall are not closed. Between the output pin head side and The is an electronic component mounting board, wherein the solder is penetrated filled.

The most remarkable point in the present invention is that when the resin sealing frame of the substrate is bonded to the substrate, an opening is formed in the resin sealing frame so that the upper portion of the through hole is not closed. And that the gap between the inner wall of the through hole and the head of the input / output pin is filled with solder.

In the present invention, the portion corresponding to the through hole corresponds to the upper portion of the through hole when a resin sealing frame is bonded and mounted on the upper portion of the through hole in the electronic component mounting board. This is the part of the resin sealing frame.

The opening is an air vent having a cutout and a through hole formed in a corresponding portion of the resin sealing frame, and an upper portion of the through hole being open. Therefore, the size, shape, and the like of the opening may be any shape that allows the air to escape and the detergent for washing to penetrate without the upper part of the through hole being sealed.

[Action and effect]

In the electronic component mounting substrate according to the present invention, since the upper portion of the through hole is open, when the substrate is immersed in the molten solder bath, the molten solder is sufficiently immersed in the through hole. Will be filled. Then, the gap between the inner wall of the through hole and the side surface of the head of the input / output pin is reliably filled with solder (see, for example, FIG. 3). Therefore, the input / output pins can be electrically connected to the through holes in a favorable state, and the reliability of the product is improved.

Further, the flux and the like remaining in the through-hole are washed away by the solvent that has entered through the opening during the washing, so that the through-hole input / output pins and the like do not corrode due to the flux. In addition, the air in the through hole does not expand due to heating during wire bonding and resin sealing and escapes through the opening and escapes. Never.

Therefore, according to the present embodiment, it is possible to provide an electronic component mounting board that is excellent in the reliability and durability of the product and in the electrical connection between the through hole and the input / output pin.

〔Example〕

A substrate according to an embodiment of the present invention will be described with reference to FIGS.

That is, as shown in FIG. 1 and FIG. 2, the substrate of this example includes an electronic component mounting portion 2 formed on an insulating substrate 1 and a portion extending around the electronic component mounting portion 2 on the insulating substrate 1. A plurality of conductor circuits 3 formed so as to be present, a through hole 5 formed at one end of the conductor circuit 3, and a resin seal placed above the conductor circuit 3 so as to surround the electronic component mounting portion 2. A stop frame 4 is provided.

The resin sealing frame 4 has an opening 40 at a portion corresponding to the through hole 5 in the substrate.
When the substrate is mounted on the substrate by adhesive bonding, the opening 40 provided in the resin sealing frame 4 opens the upper part of the through hole 5. The size and shape of the opening 40 are not particularly limited, and may be any size as long as air can escape or a solvent can enter during cleaning. Further, the opening 40 can be formed after the resin sealing frame 4 is bonded and bonded to the substrate. However, it is preferable from the viewpoint of workability that the resin sealing frame 4 is formed in advance in a portion corresponding to the through hole by, for example, drilling.

In manufacturing the above substrate, first, a substrate made of a glass triazine-based composite material is used as the insulating substrate 1. Then, a plurality of conductor circuits and through holes are formed in the insulating substrate 1 by drilling, applying a photosensitive resin, etching or the like. In addition, at a substantially central portion of the substrate,
An electronic component mounting portion 2 having a space substantially larger than an electronic component, for example, a semiconductor (chip) is formed by counterboring or the like.

On the other hand, the resin sealing frame 4 is formed in a predetermined size and shape by press punching or the like using a substrate made of a glass triazine-based composite material having the same quality as the insulating substrate 1.

Then, at a predetermined position on the substrate, that is, at a position surrounding the electronic component mounting portion, the resin sealing frame is placed by being adhesively bonded via an adhesive layer 41 made of an epoxy resin sheet or the like. In addition, at the time of the adhesive bonding, after the resin sealing frame 4 is positioned at a predetermined position on the substrate, the resin sealing frame 4 is heated at about 150 ° C.
The resin sealing frame 4 is placed on the substrate by pressing under the heating and pressing conditions of 0 kg / cm ² .

Next, as shown in FIG. 3, a substrate for mounting electronic components, which is a basic form of this example, is prepared. That is, the input / output pins 6 are inserted from below the through holes 5 in the substrate and temporarily fixed, and then the substrate is immersed in a molten solder bath. As a result, the input / output pins 6 are electrically connected to each other with the solder 7 sufficiently penetrating and filling the gap between the side surface of the head 61 and the inner wall of the through hole 5 with the head 61 exposed. You. Reference numeral 62 indicates a flange portion of the input / output pin 6.

Further, as another embodiment of the electronic component mounting board of the present embodiment, as shown in FIGS.
The openings 7 are also filled with the solder 7 by permeation.

That is, as shown in FIG. 4, in one mode, the notch portion 401 smaller than the diameter of the through hole 5 is filled with the solder 7 and the nodal portion 71 of the solder 7 is exposed in a hemispherical shape. .

In another embodiment, the solder 7 is filled in the through hole 42 of the resin sealing frame 4 and the section 71 is exposed in a hemispherical shape.

Thus, in either case, the input / output pins 6 are reliably electrically connected in the through holes 5.

After the solder bonding, the substrate is washed with a solvent such as freon in order to wash and remove the flux and the like remaining in the through holes 5 and the like.

Since the substrate of this example is configured as described above, it has the following effects.

That is, since the upper portion of the through hole 5 is open, a cavity is not generated, and the flux remaining during cleaning can be removed by washing. Therefore, the through holes 5, the input / output pins 6, and the like do not corrode due to the flux or the like.

Further, since air is not confined in the through-hole 5, even when the substrate is heated by the resin sealing frame during wire bonding, the insulating substrate and the resin sealing valve do not peel off.

Further, since the opening 40 is provided above the through hole 5, the molten solder is sufficiently penetrated and filled in the through hole 5, and the inner wall of the through hole 5 and the input / output pins 6 are formed.
The space between the head 61 and the side surface of the head 61 is sufficiently filled with solder. Therefore, the electrical connection of the input / output pins is performed in a good state.

Therefore, according to the present invention, it is possible to provide an electronic component mounting board which is excellent in product reliability, durability, and electrical connection between a through hole and an input / output pin.

[Brief description of the drawings]

1 to 5 show an electronic component mounting board according to an embodiment of the present invention. FIG. 1 is a perspective view, FIG. 2 is a partial plan view, and FIG. Sectional view, fourth
FIGS. 5 and 5 are sectional views of another embodiment, FIGS. 6 and 7 show the conventional substrate, FIG. 6 is a perspective view thereof, and FIG. 7 is a sectional view thereof. 1 ... insulating board, 2 ... electronic component mounting part, 3 ... conductor circuit, 4
... resin sealing frame, 40 ... opening, 401 ... notch, 42 ... through hole, 5 ... through hole, 6 ... input / output pin,

Claims (1)

(57) [Claims] An electronic component mounting portion formed on an insulating substrate, a plurality of conductor circuits formed extending from the periphery of the electronic component mounting portion on the insulating substrate, and one end of the conductor circuit formed at one end of the conductive circuit. A through hole formed, a resin sealing frame adhesively bonded to the upper surface of the conductor circuit so as to surround the electronic component mounting portion, and a resin sealing frame with respect to the through hole from the side opposite to the resin sealing frame. In the electronic component mounting board into which the head of the output pin is inserted, the resin sealing frame has an opening made up of a cutout, a through hole, or the like in a portion corresponding to the through hole in the insulating board; When the resin sealing frame is bonded and bonded to the insulating substrate, an opening in the resin sealing frame is formed so as not to block an upper portion of the through hole. Between the side of the head of the input pin Electronic component carrier in gap, characterized in that solder is penetrated filled.