JP2002280479A - Surface mounting semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface mounting semiconductor device in which the conduction structure can be preserved by enhancing the bonding strength of a substrate and a resin package and preventing solder from having effect on a bonded wire at the time of mounting by soldering. SOLUTION: A light emitting element 4 is mounted conductively on one electrode 2 out of a pair of metal electrodes 2 and 3 provided on a substrate 1 utilizing insulating resin and the light emitting element 4 is bonded to the other electrode 3 through a wire 5. When they are sealed into a resin package 6 including the wire 5, cuts 8 and 9 are made in the metal electrodes 2 and 3 to expose the substrate 1 which is then bonded to the resin package 6 through resin in order to enhance the bonding strength of the substrate 1 and the resin package 6 thus preventing solder from intruding between the substrate 1 and the resin package 6 at the time of mounting by soldering.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device having a semiconductor light-emitting element or a light-receiving element, and more particularly to a surface-mounted semiconductor device which is mounted on a surface of a printed wiring board and fixed by soldering.

[0002]

2. Description of the Related Art A semiconductor light emitting device using a semiconductor light emitting element includes a shell type LED lamp in which a light emitting element is mounted on a mounting portion of a lead frame, wire-bonded and sealed with an epoxy resin, and a printed wiring board. There is a surface mount type that can be electrically mounted by soldering. Surface-mount type semiconductor light emitting devices can be made smaller and thinner than LED lamps, and are therefore frequently used in various small electronic devices.

FIG. 3A is a perspective plan view schematically showing a conventional surface-mount type semiconductor light emitting device, and FIG. 3B is a cross-sectional view taken along line CC of FIG. 3A in a state of being mounted on a printed wiring board. It is.

As shown in the figure, a surface-mount type semiconductor light emitting device has an insulating BT (Bismaleimide Tri).
azine) a substrate 1 made of resin or the like, a pair of metal electrodes 2 and 3 having both ends patterned by Au plating, and an Ag paste 7 on one metal electrode 2
Light-emitting element 4 that is conductively mounted via
And a resin package 6 using an epoxy-based resin for sealing including the wire 5 between the upper end electrode and the other metal electrode 3.

[0005] A surface-mounted type semiconductor light emitting device having such a configuration has a printed wiring board 5 as shown in FIG.
1 is electrically conductively mounted. This conductive mounting is performed by the electrode patterns 51a, 51a formed on the surface of the printed wiring board 51.
b, the metal electrodes 2 and 3 of the semiconductor light emitting device are aligned and mounted, and fixed by soldering 52 and 53, respectively. Thereby, the light emitting element 4 conducts with the power supply side and emits light when energized.

[0006]

The solders 52 and 53 made of an alloy of tin and lead are melted at about 250.degree.
a, 51b. However, in the above-described conventional semiconductor light emitting device, the resin package 6 and the substrate 1 are made of resin, and therefore have high bonding strength. However, since the resin package 6 and the metal electrodes 2 and 3 are made of resin and metal, respectively, the bonding strength is high. Is weak. Therefore, when the resin package 6 is exposed to a high temperature of about 250 ° C., the solders 52 and 53 easily infiltrate into the resin package 6 as shown in FIG.

On the other hand, after the wire 5 is bonded to the electrode on the upper surface of the light emitting element 4, it is wedge bonded to the bonding area 3e of the metal electrode 3. The wedge bonding is a method of bonding such that one end of the wire 5 is rubbed against the surface of the bonding area 3e.

However, when the solder 53 infiltrates into the resin package 6, the resin of the resin package 6 at the tip of the wedge-bonded wire 5 becomes hot and softens or expands. Such softening or expansion of the resin acts to lift the wedge bonding of the wire 5 upward, and the tip of the wire 5 may rise from the bonding area 3e. For this reason, the conduction between the wire 5 and the metal electrode 3 is cut off, and it becomes impossible to supply electricity to the light emitting element 4.

Thus, the wire 5 is connected to one of the metal electrodes 3.
Is wedge-bonded, the light emitting element 4 is affected by the solder 53 when mounted on the printed wiring board 51.
Affects current supply to Therefore, a problem such as a decrease in the yield of mounted products is caused. And
A similar problem exists not only in the field of semiconductor light emitting devices but also in all semiconductor devices in which wire-bonded devices such as light receiving devices are resin-sealed and surface-mounted by soldering.

Therefore, the present invention can maintain the conductive structure by increasing the adhesive strength between the substrate and the resin package so that the solder does not affect the wire bonded at the time of mounting by soldering. It is an object to provide a surface-mounted semiconductor device.

[0011]

According to the present invention, there is provided a surface mount type semiconductor device comprising: a substrate using an insulating resin; a pair of metal electrodes formed on the substrate; and one of the substrate and the pair of metal electrodes. In a semiconductor device including a semiconductor element mounted on a semiconductor element, a wire for bonding between the semiconductor element and at least one of the metal electrodes, and a resin package for sealing the semiconductor element and the wire, the metal electrode includes a substrate. An exposed notch is formed.

According to the present invention, the substrate and the resin package are joined together by the resin via the notch formed in the metal electrode, so that the adhesive strength between the substrate and the resin package can be increased, and furthermore, the soldering can be performed. It is possible to prevent solder from intruding between the substrate and the resin package at the time of mounting.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 is a method for manufacturing a substrate using an insulating resin, a pair of metal electrodes formed on the substrate, and one of the substrate and the pair of metal electrodes. In a semiconductor device including a semiconductor element to be mounted, a wire for bonding between the semiconductor element and at least one of the metal electrodes, and a resin package for sealing the semiconductor element and the wire, the metal electrode includes A surface-mount type semiconductor device, characterized in that a cutout portion exposing the substrate is formed, and the substrate and the resin package exposed by the cutout portion are joined to each other by a resin. Can be increased, and solder can be prevented from entering between the substrate and the resin package during mounting by soldering.

According to a second aspect of the present invention, the notch is
2. The surface mounting type semiconductor device according to claim 1, wherein the bonding point of the wire is provided between a position where the wire is bonded and a boundary of the resin package. By separating from the boundary, it is possible to prevent the solder from entering between the substrate and the resin package during the mounting by soldering and reaching the bonding point of the wire.

An embodiment of the present invention will be described below with reference to the drawings. In the present embodiment, a semiconductor light emitting device will be described as an example, and the same components as those in the conventional example shown in FIG.

FIG. 1A is a perspective plan view schematically showing a semiconductor light emitting device according to an embodiment of the present invention, FIG. 1B is a sectional view taken along line AA of FIG. 1A, and FIG. FIG. 3B is a perspective plan view showing an outline of mounting on a printed wiring board, and FIG.

Referring to FIGS. 1 and 2, the semiconductor light emitting device has a substrate 1 made of an insulating BT resin and the like, and a pair of metal electrodes 2, which are patterned at both ends by Au plating. 3 and a light emitting element 4 conductively mounted on one of the metal electrodes 2 via an Ag paste 7.
A wire 5 for bonding connection between an upper end electrode of the light emitting element 4 and a bonding area 3e of the other metal electrode 3; and a resin package 6 using an epoxy resin for sealing including the wire 5. It is composed of

A notch 8 is formed in the metal electrode 3 at a position between the bonding area 3 e where the wire is to be wedge bonded and the boundary of the resin package 6. On the other hand, a notch 9 is formed in the metal electrode 2 at a position between the portion where the light emitting element 4 is mounted and the boundary of the resin package 6. The notches 8 and 9 are formed by removing the metal electrode 3 by etching so that the substrate 1 is exposed.

In the above configuration, when the semiconductor light emitting device is mounted and mounted on the printed wiring board 51 as shown in FIG. 2, the metal electrodes 2 and 3 are mounted in alignment with the wiring patterns 51a and 51b, and the solder 52 is mounted. , 53 for continuity. At this time, although the resin package 6 is exposed to a high temperature of about 250 ° C., the resin package 6 is firmly joined to the substrate 1 through the cutouts 8 and 9 exposing the substrate 1. 52 and 53 are prevented from infiltrating into the resin package 6, and the softening and expansion of the resin of the resin package 6 are prevented. Since the notches 8 and 9 are formed near the boundary of the resin package 6, even if the solders 52 and 53 infiltrate into the resin package 6, the flow of the molten solder is controlled by the notches 8 and 9. Will be blocked. Therefore, the wedge-bonded wire 5 does not rise from the bonding area 3e, and the conduction structure between the wire 5 and the metal electrode 3 is reliably maintained.

As described above, a conductive structure to the light emitting element 4 can be ensured only by forming the cutouts 8 and 9 on a part of the surface of the metal electrodes 2 and 3, and the product after mounting on the printed wiring board 51. Can be greatly improved.

In the above example, a semiconductor light emitting device in which the light emitting element 4 is mounted on the metal electrode 2 has been described. However, after the light emitting element 4 is mounted on the substrate 1 with an insulating resin, the metal electrodes 2 and 2 are bonded by wire bonding. A structure that is electrically connected to 3 may be used.
In addition, the present invention can be applied to a photocoupler including a light receiving element and other semiconductor devices.

[0022]

According to the present invention, the substrate is exposed by providing a notch in the metal electrode, and the exposed substrate and the resin package can be firmly joined to each other through the notch by the resin. It is possible to prevent solder from intruding between the substrate and the resin package at the time of mounting.

Further, according to the present invention, a notch is provided between the position where the wire is bonded and the boundary of the resin package, and the bonding point of the wire is separated from the boundary of the resin package with the notch interposed therebetween. It is possible to prevent solder from entering between the substrate and the resin package at the time of mounting and reaching the bonding point of the wire.

For this reason, when the wire is sealed by the resin package, the resin is not softened or expanded near the bonding point, and the floating of the wire is prevented. Therefore, the conductive structure at the time of surface mounting is preserved, and high-yield manufacturing becomes possible.

[Brief description of the drawings]

1A is a perspective plan view schematically showing a semiconductor light emitting device according to an embodiment of the present invention, and FIG. 1B is a sectional view taken along line AA of FIG.

FIG. 2A is a perspective plan view schematically showing a state of mounting on a printed wiring board, and FIG. 2B is a sectional view taken along line BB of FIG.

3A is a perspective plan view schematically showing a conventional surface-mount type semiconductor light emitting device, and FIG. 3B is a cross-sectional view taken along the line CC of FIG. 3A in a state of being mounted on a printed wiring board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2, 3 Metal electrode 3e Bonding area 4 Light emitting element 5 Wire 6 Resin package 7 Ag paste 8, 9 Notch 51 Printed wiring board 51a, 51b Wiring pattern 52, 53 Solder

Claims (2)

[Claims] A substrate using an insulating resin; a pair of metal electrodes formed on the substrate; a semiconductor element mounted on one of the substrate and the pair of metal electrodes;
In a semiconductor device having a wire for bonding between the semiconductor element and at least one of the metal electrodes, and a resin package for sealing the semiconductor element and the wire, the metal electrode has the substrate exposed. A surface-mounted type semiconductor device, wherein a notch is formed. 2. The surface-mounted semiconductor device according to claim 1, wherein said cutout portion is provided between a position where said wire is bonded and a boundary of said resin package.