JPH07244231A - Optical coupling device, semiconductor light-emitting element and relay - Google Patents

Abstract

PURPOSE:To provide an optical coupling device which is easily producible and has a high light transmission efficiency. CONSTITUTION:A pair of light emission-side lead frames 3a, 3b and a pair of light reception-side lead frames 4a, 4b are formed from one sheet of a metallic sheet. A light-emitting element packaging part 5 is provided with an approximately U-shaped aperture 7 at its front end. A light-emitting element 1 with its light emitting surface facing downward is packaged atop the light emission-side lead frame 3a so as to be positioned in the aperture 7. A light receiving element with its light receiving surface facing upward is packaged atop the light reception side lead frame 4a in a light receiving element packaging part 6. A pair of the light emission-side lead frames 3a, 3b are bent to position the light emitting element 1 diagonally above the light receiving element 2. The light-emitting element 1, the light-receiving element 2, etc., are fixed by a transparent resin 9 and further, this transparent resin 9 is covered by a sealing resin 10 to form the optical coupling device A. As a result, both of the light emitting element 1 and the light receiving element 2 are packaged in the same direction and the light emitted from the light emitting element 1 is received directly by the light receiving element 2 through the aperture 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical coupling device, a semiconductor light emitting device, and a relay. More specifically, the present invention relates to an optical coupling device for transmitting signals by a semiconductor light emitting element and a semiconductor light receiving element, a semiconductor light emitting element suitable for the optical coupling device, and a relay using the optical coupling device.

[0002]

2. Description of the Related Art An optical coupling device is, for example, an SSR.
(Solid state relay), specifically MOS-SS
It is used in many applications such as R. This MOS-SSR controls an output signal by using a voltage control mechanism of a MOS-FET based on an output voltage from a light receiving element of an optical coupling device, and an external circuit connected to the SSR is turned on, The OFF control can be performed. The optical coupling device used for these applications has conventionally the following structure.

FIG. 11 shows a planar type optical coupling device J.
And two pairs of lead frames 51, 5 on the same plane.
2 is arranged, the light emitting element 53 is mounted on the pair of lead frames 51, and the light receiving element 54 is mounted on the remaining pair of lead frames 52. The lead frames 51, 52, the light emitting element 53, and the light receiving element 54 are fixed with a transparent resin 55, and the periphery thereof is sealed with a sealing resin 56 such as white epoxy resin. The electric signal input from the pair of lead frames 51 is converted into an optical signal L by the light emitting element 53, and is emitted upward from the emission window on the upper surface of the light emitting element 53. Emitted optical signal L
Is reflected at the interface between the transparent resin 55 and the sealing resin 56, and the reflected optical signal L is received by the light receiving element 54. The received optical signal L can be extracted as an electric signal from the pair of lead frames 52 remaining after being converted into an electric signal again by the light receiving element 54. In this planar type optical coupling device J, two pairs of lead frames 51, 5
Since the two are arranged on the same plane, two pairs of lead frames 51 and 52 can be simultaneously formed by processing one metal plate. Further, since both the light emitting element 53 and the light receiving element 54 can be mounted on the same surface side of the lead frames 51, 52, the mounting process is simple and the optical coupling device J can be manufactured with high yield, and the manufacturing cost is low. Has the advantage that

However, since the optical signal L emitted from the light emitting element 53 is once reflected by the opaque sealing resin 56 and received by the light receiving element 54, the signal transmission efficiency is poor and the output from the light receiving element 54 is small. There was a point.

Further, FIG. 12 shows an opposed type optical coupling device K in which two pairs of lead frames 51 and 52 are arranged vertically and a light emitting element 53 is arranged above the lead frame 51. The light receiving element 54 is mounted on the upper surface of the lead frame 52 arranged on the lower side. In the optical coupling device K, since the optical signal L emitted from the light emitting element 53 is directly received by the light receiving element 54, there is an advantage that the signal transmission efficiency is large and the output is large.

However, the two pairs of lead frames 51,
52 must be vertically opposed to each other in parallel, and the distance between the two pairs of lead frames 51, 52 must be strict. Therefore, it is difficult for the light receiving element 54 to efficiently receive the optical signal L emitted from the light emitting element 53, and the yield of the optical coupling device K is poor due to insufficient output. The light emitting element 53 is the lead frame 5
Since the light emitting element 53 must be mounted on the lower surface of the lead frame 51 in advance, it is necessary to mount the light emitting element 53 on the upper surface of the lead frame 51 in advance, and then the upper surface and the lower surface of the lead frame 51 are inverted. Further, it is necessary to process the two metal plates to form the upper and lower lead frames 51 and 52, respectively, which causes a problem of high manufacturing cost.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the drawbacks of the above conventional examples, and an object of the present invention is to provide an optical coupling device having high signal transmission efficiency and low manufacturing cost. To do. Another object is to provide a semiconductor light emitting element suitable for this optical coupling device.

[0008]

The optical coupling device of the present invention comprises:
An optical coupling device having a lead frame on which a light emitting element is mounted and a lead frame on which a light receiving element is mounted is characterized in that at least one of the lead frames has an opening.

The light emitting element or the light receiving element may be mounted in the opening, and the light emitting surface side of the light emitting element or the light receiving surface side of the light receiving element may be used as a lead frame having the opening. It is desirable to implement it.

It is preferable that the light emitting surface of the light emitting element and the light receiving surface of the light receiving element are opposed to each other.

The lead frame on which the light emitting element is mounted or the lead frame on which the light receiving element is mounted may be bent to form a step between the light emitting surface of the light emitting element and the light receiving surface of the light receiving element.

The light emitting surface of the light emitting element or the light receiving surface of the light receiving element may be tilted. For this purpose, a mounting surface of a lead frame on which the light emitting element is mounted or a lead frame on which the light receiving element is mounted is mounted. The mounting surface of may be inclined.

The semiconductor light emitting device of the present invention is characterized in that electrodes are partially formed on the upper surface and the lower surface of the semiconductor light emitting device body. At this time, it is preferable to form an electrode on the upper peripheral area or the lower peripheral area of the semiconductor light emitting element body, and further, the electrode on the upper surface of the semiconductor light emitting element body and the electrode on the lower surface of the semiconductor light emitting element body do not overlap each other. It is desirable to form it.

An optical coupling device may be constituted by the semiconductor light emitting element and the light receiving element according to the present invention,
In particular, it is desirable to combine it with each of the above optical coupling devices.

Further, the relay of the present invention comprises the optical coupling device of the present invention and output signal control means for controlling an output signal based on an electrical output from the light emitting element of the optical coupling device. Is characterized by. For example, a MOS-FET can be used as the control signal output means.

[0016]

In the optical coupling device of the present invention, since the lead frame on which the light emitting element or the light receiving element is mounted is provided with the opening, the light emitting surface of the light emitting element or the light receiving surface of the light receiving element is positioned in the opening. If mounted on a lead frame, the light emitted from the light emitting element can be received by the light receiving element through the opening. At this time, if the light emitting surface of the light emitting element or the light receiving surface side of the light receiving element is mounted on a lead frame having an opening, both the light emitting element and the light receiving element can be mounted on the same surface side of the lead frame. Further, since the light emitting surface of the light emitting element and the light receiving surface of the light receiving element are opposed to each other, the emitted light emitted from the light emitting surface of the light emitting element can be directly received by the light receiving surface of the light receiving element.

That is, in the optical coupling device of the present invention,
Light can be emitted downward from the light emitting element mounted on the upper surface of the lead frame positioned in the opening, and the emitted light can be directly received by the light receiving element mounted on the upper surface of the lead frame. Therefore, the light emitting element and the light receiving element can be easily mounted as in the conventional planar type optical coupling device, and the signal transmission efficiency can be increased similarly to the facing type optical coupling device.

For this purpose, it is preferable that the lead frame on which the light emitting element is mounted or the lead frame on which the light receiving element is mounted is bent to provide a step between the light emitting surface of the light emitting element and the light receiving surface of the light receiving element. By bending the lead frame in this way, one metal plate can be processed to simultaneously form four lead frames, and the cost of the optical coupling device can be kept low.

At this time, the light-receiving surface of the light-emitting element or the light-receiving surface of the light-receiving element is tilted by inclining the mounting surface of the lead frame, and the light-receiving surface of the light-receiving element is arranged substantially perpendicular to the normal line of the light-emitting element. If so, the light receiving efficiency can be further improved.

In the semiconductor light emitting device of the present invention, the electrode is partially formed on the upper surface or the lower surface of the semiconductor light emitting device body, so that the light emitted from the semiconductor light emitting device body is less likely to be blocked by the electrode. Therefore, the light utilization rate can be increased. At this time, if the electrodes are formed on the upper peripheral area or the lower peripheral area of the semiconductor light emitting element body, the electrodes of the light emitting element can be directly mounted on the lead frame in accordance with the openings of the lead frame in the optical coupling device. Therefore, the emitted light is not blocked by the lead frame.

Further, by forming each electrode so that the electrode on the upper surface of the semiconductor light emitting element and the electrode on the lower surface do not overlap each other, the light utilization rate of the light emitting element can be further increased.

Therefore, by using such a semiconductor light emitting device, an optical coupling device having higher signal transmission efficiency can be provided.

Since the relay of the present invention is provided with the above-mentioned optical coupling device, it is possible to increase the drive current or voltage of the output signal control means and increase the response speed of the relay. Further, since the signal transmission efficiency is good, the output signal control means can be driven with a small amount of light emission, and the relay can be ON / OFF controlled with a small drive current of the light emitting element. Further, since the optical coupling device can be used at low cost, an efficient relay can be provided at low cost.

[0024]

1 (a), 1 (b) and 1 (c) are a schematic plan sectional view, a schematic side sectional view and a schematic front sectional view, respectively, showing the structure of an optical coupling device A according to an embodiment of the present invention. 1 is LED
Is a light emitting element such as a photodiode or a phototransistor, 3a and 3b are light emitting side lead frames, and 4a and 4b are light receiving side lead frames. A light emitting element mounting portion 5 is formed at the tip of one light emitting side lead frame 3a formed in a linear shape so as to project inward, and the remaining light emitting side lead frame 3b is formed in a stepwise shape and its tip is formed. Are close to the light emitting element mounting portion 5. Further, a pair of light-receiving side lead frames 4a, 4b is formed so as to be symmetrical with the light-emitting side lead frames 3a, 3b, and one of the light-receiving side lead frames 4a formed in a plane linear shape is projected inward at the tip thereof. Thus, the light receiving element mounting portion 6 is formed, and the remaining light receiving side lead frame 4b is formed in a step shape, and the tip thereof is close to the light receiving element mounting portion 6. These four light emitting side and light receiving side lead frames 3a, 3b, 4a, 4b are made at the same time by punching or etching from a single metal plate, and the pair of light emitting side lead frames 3a, 3b are respectively placed on the upper side. It is bent and arranged so as to be parallel to the light-receiving side lead frames 4a and 4b at a predetermined interval. In addition, the light receiving side lead frames 4a, 4
It is also possible to arrange so that b is bent downward. A substantially U-shaped opening 7 is provided at the tip of the light emitting element mounting portion 5, and the light emitting window of the light emitting element 1 such as an LED is positioned in the opening 7 so that the light emitting element mounting portion 5 has The light emitting element 1 is mounted on the upper surface by a conductive resin or the like, and the gold wire 8 is laid between the remaining light emitting side lead frame 3b. At this time, it is desirable to use the light emitting element 1 in which electrodes are formed at both ends of the light emitting surface and a light emitting window is opened so as to be sandwiched between the electrodes, as described later. Further, the light receiving element 2 is mounted on the upper surface of the light receiving element mounting portion 6 with the light receiving surface facing upward by a conductive resin or the like, and the gold wire 8 is wired between the remaining light receiving side lead frame 4b. Also,
The light receiving element 2 has light emitting side lead frames 3a and 3b and light receiving side lead frames 4a and 4b arranged obliquely below the light emitting element 1, and the optical signal L emitted from the light receiving element 2 is opened. The light receiving element 2 receives the light directly from 7. In this way, the pair of light emitting side lead frames 3a, 3b on which the light emitting element 1 is mounted and the pair of light receiving side lead frames 4a on which the light receiving element 2 is mounted,
4b is fixed by being covered with a transparent resin 9 such as silicon resin, and the outside of the transparent resin 9 is covered with a sealing resin 10. The sealing resin 10 can be formed from, for example, epoxy resin by low pressure molding, but the sealing resin 10 may be formed by a method other than this method.

Therefore, the light emitting side lead frames 3a, 3b
When an input signal is input to, the light emitting element 1 converts it into an optical signal L according to the input signal, and the optical signal L is emitted from the opening 7 toward the light receiving element 2. Emitted optical signal L
Is transmitted through the transparent resin 9 and directly received by the light receiving element 2.
The optical signal L received by the light receiving element 2 is converted into an electric signal again and output from the light receiving side lead frames 4a and 4b.

In this optical coupling device A, since the optical signal L emitted from the light emitting element 1 can be directly received by the light receiving element 2, the signal transmission efficiency is good and a large output can be obtained. Further, since both the light emitting element 1 and the light receiving element 2 can be mounted in the same plane direction (lead frame upper surface) of the light emitting side lead frame 3a and the light receiving side lead frame 4a, the manufacturing process is not complicated.
Moreover, by bending the light emitting side lead frames 3a and 3b,
Since the light receiving element 2 is positioned diagonally below the light emitting element 1, the four lead frames 3 on the light emitting side and the light receiving side are provided.
Since a, 3b, 4a and 4b can be made from one metal plate, the manufacturing cost can be kept low.

2A, 2B, and 2C are a plan view, a front view, and a bottom view, respectively, showing the structure of the semiconductor light emitting device 1 according to one embodiment of the present invention. This semiconductor light-emitting device 1 is a light-emitting diode having a single-hetero structure, and is formed on an n-GaAs substrate 11 by, for example, a liquid phase epitaxial growth method (LPE method).
A GaAs clad layer 12 is grown, and then p-Ga
The As active layer 13 is grown. In addition, p-GaAs
Band-shaped front surface electrodes 14 are formed on both ends of the upper surface of the active layer 13, and a circular back surface electrode 15 is formed on the rear surface of the n-GaAs substrate 11 at substantially the center. The front surface electrode 14 and the back surface electrode 15 are formed so as not to overlap with each other. Therefore, in the light emitting element 1, the active layer 13 is formed.
Part of the light generated in the above and directed upward is exposed in the active layer 13
The light emitted from the front surface, that is, the surface light emitting window 17 is emitted upward from the light emitting element 1, and the remaining light is reflected by the front surface electrode 14, and emitted from the exposed back surface of the substrate, that is, the light emitting window 18, downward to the light emitting element 1. Further, a part of the light generated in the active layer 13 and directed downward is emitted from the backside light emitting window 18 to the lower side of the light emitting element 1, and the remaining light is reflected by the backside electrode 15 and from the front surface emitting window 17 to the upper side of the light emitting element 1. Is emitted to. Therefore, most of the light generated in the active layer 13 can be extracted from the front surface emission window 17 and the back surface emission window 18 of the light emitting element 1, and the light utilization rate of the semiconductor light emitting element 1 can be increased.

The surface emitting window 17 of the light emitting device 1 having such a structure is positioned downward in the opening 7, and the surface electrode 1
4 is mounted on the light emitting element mounting portion 5 to configure the optical coupling device B, the optical signal L emitted from the surface light emitting window 17 to the lower side of the light emitting element 1 is directly received by the light receiving element 2 as shown in FIG. In addition to the above, the optical signal L emitted from the rear light emitting window 18 to the upper side of the light emitting element 1 is also reflected by the interface between the transparent resin 9 and the sealing resin 10 and received by the light receiving element 2. Therefore, most of the light generated by the light emitting element 1 can be effectively used, the signal transmission efficiency in the optical coupling device B can be further improved, and a larger output can be taken out.

As shown in FIG. 2A, when the surface electrode 14 is formed in a strip shape at the end of the active layer 13, the surface electrode 14 is formed on the light emitting element mounting portions 5 on both sides of the opening 7. The optical signal L emitted from the surface emission window 17 can be received by the light receiving element 2 through the opening 7 without any waste. If a die bonding apparatus having a mounting accuracy of about 30 μm is used, about 1
The electrode width of about 00 μm can be mounted on the light emitting element mounting portion 5 with sufficient accuracy.

The structure of the light emitting device 1 of the present invention can be applied to the light emitting devices 1 having other structures, such as a double hetero structure or a homo structure. The same effect can be obtained with other materials such as InGaAsP / InP series, and the present invention is not limited to light emitting diodes and can be applied to, for example, semiconductor lasers.

FIG. 4 shows an optical coupling device C which is another embodiment of the present invention, and FIGS. 4 (a), (b) and (c) are schematic plan sectional views showing the structure of the optical coupling device C, respectively. It is a figure, a schematic side sectional view, and a schematic right sectional view. In this optical coupling device C, four lead frames 3a on the light emitting side and the light receiving side are provided.
3b, 4a and 4b are each formed in a plane straight line shape, and
The light emitting side lead frames 3a and 3b and the two light receiving side lead frames 4a and 4b are arranged in parallel with each other. Further, the light emitting side lead frame 3a,
3b is bent upward and is arranged in parallel with the light-receiving side lead frames 4a and 4b at a predetermined interval, and the light-receiving element 2 is arranged obliquely below the light-emitting element 1. Further, a light emitting element mounting portion 5 is formed at the tip of the light emitting side lead frame 3a, and a U-shaped opening 7 is provided at the tip, and the light emitting element 1 is aligned with the position of the opening 7. It is implemented. A light receiving element mounting portion 6 is formed at the tip of the light receiving side lead frame 4 a, and the light receiving element 2 is mounted on the light receiving element mounting portion 6.
The lead frames 3a, 3b, 4 having such a simple shape are
An optical coupling device C having a high signal transmission efficiency can be produced by simply producing a and 4b.

Further, FIG. 5 shows the structure of an optical coupling device D which is still another embodiment of the present invention. In this optical coupling device D, the light emitting element mounting portion 5 is provided with a rectangular opening 7, and the light emitting element 1 is mounted so as to be positioned in the opening 7. The rectangular opening 7 may be provided in this way, and the optical signal L may be emitted from the opening 7. Further, in this case, it is desirable to use the light emitting element 1 in which the surface electrode 14 is formed in a rectangular frame shape so that the surface light emitting window 17 of the light emitting element 1 and the shape of the opening 7 are matched. Further, the shape of the opening 7 is not limited to the rectangular shape, but may be formed into a circular shape, an elliptical shape, or the like.

FIGS. 6A, 6B and 6C are a schematic plan sectional view, a schematic side sectional view and a schematic normal sectional view showing the structure of an optical coupling device E which is still another embodiment of the present invention. . The light emitted from the light emitting element 1 is generally Lambertian emitted. Therefore, in each of the above-described embodiments, the light receiving element 2 is arranged obliquely below the light emitting element 1, and therefore it is still low in terms of light receiving efficiency. Therefore, in the optical coupling device E, the light emitting element mounting portion 5 is bent as shown in FIG. 6, and the light emitting surface of the light emitting element 1 is inclined so that the normal line of the light emitting element 1 faces the light receiving surface of the light receiving element 2. There is. By thus inclining the light emitting surface, the signal transmission efficiency can be further improved. The same effect can be obtained by bending the light receiving element mounting portion 6 and inclining the light receiving surface.

Further, by bending only the light emitting element mounting portion 5 of the light emitting side lead frame 3a as in the optical coupling device F shown in FIG. 7, the light receiving surface of the light receiving element 2 is oriented in the normal direction of the light emitting element 1 as much as possible. As described above, the light receiving element 2 may be positioned obliquely below the light emitting element 1 by inclining as described above. By doing so, it is not necessary to bend the light emitting side lead frame 3b, and the manufacturing process of the optical coupling device F can be simplified. Further, as in the optical coupling device G shown in FIG. 8, both the light emitting element mounting portion 5 and the light receiving element mounting portion 6 are bent,
The light receiving surface of the light receiving element 2 and the normal line direction of the light emitting element 1 may be perpendicular to each other. Although not shown, a tilted silicon pedestal or the like may be sandwiched between the light receiving element 2 and the light receiving element mounting portion 6 so that the light receiving surface of the light receiving element 2 is tilted. Of course, a pedestal may be provided between the light emitting element 1 and the light receiving element mounting portion 5.

9A, 9B and 9C are schematic plan sectional views, schematic side sectional views and schematic normal sectional views showing the structure of an optical coupling device H which is still another embodiment of the present invention. Is.
In this optical coupling device H, the light receiving side lead frame 4
a and 4b are bent upward, and the light receiving element 2 is arranged diagonally above the light emitting element 1. The light-receiving element mounting portion 6 is provided with a rectangular or substantially U-shaped opening 7, and the light-receiving element 2 is placed on the upper surface of the light-receiving side lead frame 4a with the light-receiving surface facing down according to the position of the opening 7. Has been implemented. The light emitting element 1 is mounted on the upper surface of the light emitting element mounting portion 5 with the light emitting surface facing upward, and the optical signal L emitted from the light emitting surface of the light emitting element 1 passes through the opening 7 and is directly received by the light receiving element 2. To be done. Since the light receiving element 2 is generally larger than the light emitting element 1, the light receiving element mounting portion 6 has the opening 7
It is easier to dispose the light emitting element 1 in the opening portion 7 and mount the light receiving element 2 in the opening portion 7 than to mount the light emitting element 1 in the opening portion 7.

FIG. 10 is a schematic equivalent circuit diagram of a solid state relay (SSR) I which is an embodiment of the present invention, in which an output is provided while an input signal is applied between the input terminals 11 and 11. The terminals 12 and 12 can be turned on or off, and the circuit connected between the output terminals 12 and 12 can be turned on / off by an input signal. This solid-state relay I has output terminals 12, 1 according to the outputs of the optical coupling device of the present invention, for example, the optical coupling device A of the first embodiment and the light receiving element 2 of the optical coupling device A.
Output signal control circuit 1 for ON / OFF control between the two
3 and the like, and the output signal control circuit 13 is composed of, for example, a MOS-FET (MOS field effect transistor). Then, when an input signal is applied between the input terminals 11 and 11, the light emitting element 1 of the optical coupling device A is
The optical signal L is emitted from the light receiving element 2 toward the light receiving element 2, and the light receiving element 2 outputs an electric signal to the output signal control circuit 13 when receiving the emitted optical signal L. When an electric signal is input from the light receiving element 2 to the output signal control circuit 13, for example, ON control is performed between the output terminals 12 and 12 according to the electric signal. Therefore, by applying an input signal between the input terminals 11 and 11, the input terminals 11 and 11 and the output terminals 12 and 1 are connected.
While maintaining electrical insulation between the two, the output terminal 12,
It is possible to control ON / OFF between the 12 terminals.

In this solid state relay I, since the output from the optical coupling device A is large, the MOS-FE
The T drive voltage can be increased, the ON time of the solid state relay I can be shortened, and high speed operation can be enabled. In addition, since the signal transmission efficiency of the optical coupling device A is high, ON / OFF between the output terminals 12 and 12 can be performed with a small light emission amount.
Since the OFF control can be performed, the light emitting element drive current applied to the input terminals 11 and 11 can be reduced. Furthermore, since the cost of the optical coupling device A can be kept low, the cost of the solid state relay I can be reduced.

In this embodiment, the MOS-FET is
Although the solid state relay I using the above has been described, it can be applied to a solid state relay having an output signal control circuit using a transistor other than this. Needless to say, the optical coupling device of the present invention is not limited to solid-state relays and can be applied to various applications such as isolation circuits.

[0039]

In the optical coupling device of the present invention, an optical signal is emitted from the opening of the lead frame on which the light emitting element is mounted, or an optical signal is received from the opening of the lead frame on which the light receiving element is mounted. Therefore, the signal transmission efficiency of the optical coupling device can be improved. At this time, if the light emitting surface of the light emitting element and the light receiving surface of the light receiving element are mounted on a lead frame having openings, respectively, the mounting can be performed on the same surface side of the lead frame, thus simplifying the manufacturing process. . Further, when the light emitting surface of the light emitting element and the light receiving surface of the light receiving element are opposed to each other, the emitted light emitted from the light emitting element can be directly received by the light receiving surface of the light receiving element, and the light receiving efficiency is also good.

Further, by bending the lead frame and providing a step between the light emitting surface of the light emitting element and the light receiving surface of the light receiving element, four lead frames can be formed from one metal plate, and the optical coupling is achieved. The cost of the device can be kept low.

Furthermore, since the light emitting surface of the light emitting element or the light receiving surface of the light receiving element is inclined by inclining the mounting surface of the lead frame, for example, the light receiving surface is positioned substantially perpendicular to the normal line direction of the light emitting element. By doing so, the signal transmission efficiency of the optical coupling device can be further improved.

According to the semiconductor light emitting device of the present invention, since the electrodes are partially formed on the upper surface and the lower surface of the semiconductor light emitting device body, the light emitted from the semiconductor light emitting device body can be effectively used. it can. At this time, if the electrode is formed on the upper peripheral area or the lower peripheral area of the semiconductor light emitting element body, the electrode can be directly mounted on the lead frame while being positioned in the lead frame opening of the optical coupling device of the present invention. At this time, if the electrode on the upper surface of the semiconductor light emitting element body and the electrode on the lower surface are formed so as not to overlap with each other, the light utilization rate of the semiconductor light emitting element can be further increased.

Therefore, if such a semiconductor light emitting element is used in the optical coupling device of the present invention, it is possible to provide an optical coupling device with higher signal transmission efficiency.

Further, in the relay of the present invention, the response speed is fast, and the relay is turned on / off with a driving current of a small light emitting element.
An efficient relay that can be turned off can be provided at low cost.

[Brief description of drawings]

1A, 1B, and 1C are a schematic plan sectional view, a schematic side sectional view, and a schematic front sectional view, respectively, showing the structure of an optical coupling device according to an embodiment of the present invention.

2A, 2B, and 2C are a plan view, a side view, and a bottom view, respectively, showing the structure of a semiconductor light emitting device that is an embodiment of the present invention.

FIG. 3 is a schematic side sectional view showing the structure of an optical coupling device as another embodiment of the above.

4 (a), (b) and (c) are schematic plan sectional views showing the structure of an optical coupling device according to still another embodiment of the same,
It is a schematic side sectional view and a schematic front sectional view.

5 (a), (b) and (c) are schematic plan sectional views showing the structure of an optical coupling device which is still another embodiment of the same.
It is a schematic side sectional view and a schematic front sectional view.

6 (a), (b) and (c) are schematic plan sectional views showing the structure of an optical coupling device according to still another embodiment of the same.
It is a schematic side sectional view and a schematic front sectional view.

7 (a), (b) and (c) are schematic plan sectional views showing the structure of an optical coupling device according to still another embodiment of the same.
It is a schematic side sectional view and a schematic front sectional view.

8 (a), (b) and (c) are schematic plan sectional views showing the structure of an optical coupling device according to still another embodiment of the same,
It is a schematic side sectional view and a schematic front sectional view.

9 (a), (b) and (c) are schematic plan sectional views showing the structure of an optical coupling device according to still another embodiment of the same,
It is a schematic side sectional view and a schematic front sectional view.

FIG. 10 is a schematic equivalent circuit diagram of a relay which is an embodiment of the present invention.

FIG. 11 is a schematic cross-sectional view showing the structure of a conventional optical coupling device.

FIG. 12 is a schematic cross-sectional view showing the structure of another conventional optical coupling device.

[Explanation of symbols]

 1 Light emitting element 2 Light receiving element 3a, 3b Light emitting side lead frame 4a, 4b Light receiving side lead frame 5 Light emitting element mounting portion 7 Opening

Claims (14)

[Claims] 1. An optical coupling device having a lead frame having a light emitting element mounted thereon and a lead frame having a light receiving element mounted thereon, wherein at least one of the lead frames has an opening. 2. The optical coupling device according to claim 1, wherein the light emitting element or the light receiving element is mounted in the opening. 3. The optical coupling device according to claim 2, wherein the light emitting surface side of the light emitting element or the light receiving surface side of the light receiving element is mounted on a lead frame having the opening. 4. The optical coupling device according to claim 1, wherein the light emitting surface of the light emitting element and the light receiving surface of the light receiving element face each other. 5. A lead frame on which the light emitting element is mounted or a lead frame on which the light receiving element is mounted is bent to provide a step between the light emitting surface of the light emitting element and the light receiving surface of the light receiving element. Claims 1, 2, 3 or 4
The optical coupling device according to. 6. The light emitting surface of the light emitting element or the light receiving surface of the light receiving element is inclined.
The optical coupling device according to 2, 3, 4 or 5. 7. The optical coupling device according to claim 6, wherein the mounting surface of the lead frame on which the light emitting element is mounted or the mounting surface of the lead frame on which the light receiving element is mounted is inclined. 8. A semiconductor light emitting device, wherein electrodes are partially formed on an upper surface and a lower surface of a semiconductor light emitting device body. 9. The semiconductor light emitting device according to claim 8, wherein an electrode is formed on an upper peripheral region or a lower peripheral region of the semiconductor light emitting device body. 10. The semiconductor according to claim 8, wherein the electrodes are formed so that an electrode on the upper surface of the semiconductor light emitting element body and an electrode on the lower surface of the semiconductor light emitting element body do not overlap with each other. Light emitting element. 11. An optical coupling device comprising a light receiving element and the semiconductor light emitting element according to claim 8, 9, or 10. 12. The semiconductor light emitting device according to claim 8, 9, or 10, wherein the semiconductor light emitting device is provided.
The optical coupling device according to 4, 5, 6 or 7. 13. The method according to claim 1, 2, 3, 4, 5, 6, 7,
11. A relay comprising: the optical coupling device according to item 11 or 12; and an output signal control unit that controls an output signal based on an electrical output from a light emitting element of the optical coupling device. 14. The output signal control means includes a MOS-FE.
The relay according to claim 13, wherein T is used.