JP2010153816A - Photo coupler and its assembling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photo coupler and its manufacturing method for preventing misalignment and disconnection of wires and constituting it in a miniaturized size, together with prevention from occurrence of displacement on assembling. <P>SOLUTION: The assembling method of the photo coupler 100 includes steps: for forming a light-receiving element 101 on the upper side of a first lead frame 104; for forming a light-emitting element 102 on the lower side of a second lead frame 105 (i); and for forming an insulator 120 comprising an insulating film 103 and an insulating layer 108 on the upper side of the light-receiving element 101 in some space from the first lead frame 104, with the upper side of the insulator 120 higher than the maximal point of a bonding wire 110 and parallel to the upper side of the first lead frame 104 (ii). Further in the assembling method, the upper side of the first lead frame 104 and the lower side of the second lead frame 105 are fixed so that the upper side of the light-receiving element 101 is disposed in face to face with the lower side of the light-emitting element 102, with the insulator 120 comprising the insulating film and the insulating layer interposed between the two elements; and that the insulator is disposed in some space from the second lead frame 105 (iii). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a photocoupler and an assembling method thereof.

  A photocoupler is a device that exchanges signals with light and electrically insulates an input side (light emitting side) and an output side (light receiving side). Various techniques have been proposed to increase the withstand voltage on the input side and output side. Among them, a light emitting element and a light receiving element are opposed to each other, and an insulating film is sandwiched between them. Since the internal creepage distance between the light receiving element and the light emitting element can be increased and the withstand voltage can be improved, it is widely used.

  A method for assembling a facing photocoupler having a structure in which an insulating film is sandwiched between a general light receiving element and a light emitting element will be described with reference to FIGS. FIG. 10 shows the structure of the photocoupler obtained by the steps shown in FIGS.

  First, lead frames 104 and 105 are prepared as attachment portions of the light receiving element 101 and the light emitting element 102 (FIGS. 7A and 7A). Thereafter, the light receiving element 101 is mounted on the upper surface of the lead frame 104, the light emitting element 102 is mounted on the lower surface of the lead frame 105, and bonding wires 110 are wired to the respective lead terminals by wire bonding (FIGS. 7B and 7B). ')).

  Next, a small amount of transparent silicone resin 107 is applied to the upper surface of the light receiving element 101, and the insulating film 103 is mounted thereon, and the silicone resin 107 is cured (FIG. 7 (c ′)). Subsequently, a transparent silicone resin 106 is applied to the light emitting element 102 (FIG. 7C). Thereafter, the upper surfaces of the lead frame 104 and the lower surface of the lead frame 105 are completely cured and fixed so that the light emitting element 102 and the light receiving element 101 face each other with the insulating film 103 interposed therebetween ( FIG. 8, FIG. 9 (a)). Thereby, the optical coupling between the light receiving element 101 and the light emitting element 102 is formed.

  Next, the sealing material 109 is formed (FIG. 9B). Thereafter, unnecessary portions of the lead frame are removed and shaped into a shape as shown in FIG.

The process of mounting the insulating film 103 on the light receiving side lead frame 104 will be described in the above assembly process. First, as shown in FIGS. 7C to 8B, a soft transparent silicone resin 107 is applied to the light receiving side lead frame 104 and an insulating film 103 is mounted. Then, as shown in FIG.8 (c), the insulating film 103 sinks with dead weight, and inclines in various directions. Therefore, the insulating film 103 tilts in various directions, and causes rotation and positional deviation.
As shown in FIG. 10, the insulating film 103 is supported by the uppermost point 130 of the bonding wire 110. For this reason, the bonding wire 110 is deformed by an impact at the time of mounting or the dead weight of the insulating film 103, which causes an assembly failure of the photocoupler.

  As shown in FIG. 12, in Patent Document 1, a support portion (22a, 22b) is provided on the lead frame 16, the insulating film 20 is mounted, and the insulating film 20 is fixed with a resin. A technique for removing the support portions (22a, 22b) is disclosed later. According to this technique, the insulating film 20 is not displaced, and the insulating film 20 does not touch the bonding wire 19, so that deformation of the wire can be prevented. Further, since the insulating film 20 is not in contact with the bonding wire 19, the dielectric strength is maintained.

Further, as shown in FIG. 11, Patent Document 2 discloses a photocoupler having a structure in which a light receiving chip 24 and a light emitting chip 23 are stacked via a transparent insulating layer 25 with respect to the above-described facing photocoupler. Proposed.
In this photocoupler, the transparent insulating layer 25 is formed to protrude outward from the bottom surface of the upper light emitting chip 23, and a part thereof is bent so as not to interfere with the wire bonding of the lower light receiving chip 24. Yes.

JP 2004-186297 A Japanese Patent Laid-Open No. 06-045636

  In the manufacturing method of Patent Document 1, the support portions (22 a and 22 b) become an obstacle during bonding of the bonding wires 19. In addition, a process of punching the support part with a cutting punch or the like before the resin sealing is added, but in the state before the resin sealing, it is difficult to fix to the cutting machine, and the bonding wire breaks due to the impact when punching. There are great concerns. Further, since it is necessary to form a support portion, it is difficult to reduce the size.

According to the present invention, providing a first optical element on the upper surface of the first lead frame and providing a second optical element on the lower surface of the second lead frame;
The upper surface of the first optical element is higher than the highest point of the bonding wire connecting the upper surface of the first lead frame and the upper surface of the first optical element, and is parallel to the upper surface of the first lead frame. Providing an insulating portion having an upper surface spaced apart from the first lead frame;
The first lead frame such that an upper surface of the first optical element and a lower surface of the second optical element are opposed to each other with the insulating portion interposed therebetween, and the insulating portion is separated from the second lead frame. Fixing the upper surface of the second lead frame and the lower surface of the second lead frame;
A method of assembling a photocoupler is provided.

According to the present invention, the first lead frame;
A second lead frame provided to face the upper surface of the first lead frame;
A first optical element provided on the upper surface of the first lead frame so as to face the lower surface of the second lead frame;
A second optical element provided on the lower surface of the second lead frame so as to face the upper surface of the first optical element;
A bonding wire connecting the upper surface of the first lead frame and the upper surface of the first optical element;
The first lead frame provided on the upper surface of the first optical element has an upper surface higher than an uppermost point of the bonding wire, and the first lead frame and the second lead frame are separated from each other. An insulating part having an upper surface parallel to the upper surface;
A photocoupler is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the photocoupler which can prevent the deformation | transformation and cutting | disconnection of a wire and can reduce a size, and its assembly method are implement | achieved, preventing rotation and position shift of an insulating film at the time of an assembly. .

It is a figure which shows the photocoupler of embodiment of this invention. It is a figure which shows the photocoupler of the modification of this invention. It is a figure which shows the photocoupler of the modification of this invention. It is a figure which shows the assembly method of the photocoupler of embodiment of this invention. It is a figure which shows the assembly method of the photocoupler of embodiment of this invention. It is a figure which shows the assembly method of the photocoupler of embodiment of this invention. It is a figure which shows the assembly method of the conventional photocoupler. It is a figure which shows the assembly method of the conventional photocoupler. It is a figure which shows the assembly method of the conventional photocoupler. It is a figure which shows the conventional photocoupler. It is a figure which shows the conventional photocoupler. It is a figure which shows the assembly method of the conventional photocoupler. It is a figure which shows the photocoupler of the modification of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate. In the present embodiment, description will be made by defining the front-rear, left-right, up-down directions as shown. However, this is provided for the sake of convenience in order to briefly explain the relative relationship between the components. Therefore, the direction at the time of manufacture and use of the product which implements the present invention is not limited.
FIG. 1 shows an embodiment of a photocoupler 100 according to the present invention.
The photocoupler 100 of the present embodiment includes a first lead frame 104, a second lead frame 105 provided to face the upper surface of the first lead frame 104, and a lower surface of the second lead frame 105. The first optical element (light receiving element 101) provided on the upper surface of the first lead frame 104 so as to face the lower surface of the second lead frame 105 so as to face the upper surface of the light receiving element 101. The second optical element (light emitting element 102), a bonding wire 110 connecting the upper surface of the first lead frame 104 and the upper surface of the light receiving element 101, and an upper surface higher than the uppermost point of the bonding wire 110, A first lead frame provided on the upper surface of the light receiving element 101 by separating the first lead frame 104 and the second lead frame 105 from each other. An insulating portion 120 having a 04 parallel to an upper top surface.

The insulating portion 120 is not particularly limited as long as it is a material that transmits light, but in the present embodiment, the insulating portion 120 is made of a material that is entirely transparent. For example, the insulating unit 120 includes the insulating layer 108 and the insulating film 103. The insulating unit 120 may be a laminated film made of a plurality of different materials. The insulating unit 120 is disposed between the upper surface of the light receiving element 101 and the lower surface of the light emitting element 102. A flat insulating film 103 is provided on the upper surface of the insulating layer 108. The insulating unit 120 is disposed apart from the first lead frame 104 and the second lead frame 105. The insulating layer 108 has an upper surface parallel to the upper surface of the first lead frame 104. The insulating layer 108 has a top surface higher than the uppermost point of the bonding wire 110, and the insulating film 103 has a larger area than the top surface of the insulating layer 108.
Here, “parallel” means that, when the insulating unit 120 is disposed on the upper surface of the light receiving element 101, an error of a range within which the effect of the present embodiment is achieved is allowed. Further, “arrange C from B at a distance from A” means that C is arranged between A and C via B different from C. For example, the above-mentioned “place the insulating portion 120 apart from each other” means that the upper surface of the first lead frame 104 is interposed via a member different from the insulating portion 120 such as transparent resin (106, 107) and the light receiving element 101. And the insulating part 120 on the lower surface of the second lead frame 105. In order to dispose the insulating film 103 apart, the insulating film is formed on the upper surface of the first lead frame 104 and the lower surface of the second lead frame 105 through an insulating layer 108 different from the insulating film 103. 103 is arranged.

  The light emitting element 102 and the light receiving element 101 are, for example, a light emitting diode and a photodiode, respectively. An insulating layer 108 and a flat insulating film 103 are fixed to the light receiving element 101 and the lead frame 104 by a transparent resin 107. Further, the light emitting element 102 and the lead frame 105 are fixed to the flat insulating film 103 by a transparent resin 106. Resins 106 and 107 are, for example, silicone resins. Further, a sealing material 109 is formed so as to cover these light emitting element 102, light receiving element 101, lead frame 104, flat insulating film 103, insulating layer 108 and lead frame 105.

  As shown in FIG. 1, the insulating layer 108 has an upper surface higher than the uppermost point of the bonding wire 110 that connects the upper surface of the first lead frame 104 and the upper surface of the light receiving element 101. The insulating layer 108 may be a light-transmitting insulator. The insulating layer 108 can be obtained, for example, by forming it by a wafer process.

Next, the wafer process will be described. This wafer process includes the following steps.
Forming a resin layer on the wafer having the light receiving element 101;
Patterning the resin layer into a predetermined shape and forming an insulating layer on the light receiving element 101;
A step of dividing the wafer into individual light receiving elements 101 on which the insulating layer 108 is formed.

  In the step of forming the insulating layer 108 on the light receiving element 101, the insulating layer 108 is formed in a portion excluding the bonding pad on the light receiving element 101. Further, the thickness of the insulating layer 108 is determined so that the upper surface of the insulating layer 108 is higher than the uppermost point of the bonding wire 110. Examples of the material of the insulating layer 108 include materials that do not deform in the assembly process, such as a solid insulating material of polyimide resin.

  After the step of dividing into light receiving elements 101, the light receiving elements 101 in which the insulating layer 108 is formed are mounted on the light receiving side lead frame 104. Further, a bonding wire 110 is connected to a bonding pad on the light receiving element 101.

  Note that in the step of forming the resin layer, when a plurality of light receiving elements 101 are provided on the wafer, a plurality of light receiving elements 101 on which the insulating layers 108 are formed can be formed at a time.

  Further, when the insulating layer 108 is mounted at the time of assembly, the insulating layer 108 can be obtained by die cutting with a mold or the like. Therefore, the material of the insulating layer 108 is preferably a material and a thickness that are transparent and can be easily cut out with a mold or the like. An example of this material is a solid insulating material such as a polyimide resin.

The insulating layer 108 is provided on the upper surface of the light receiving element 101 on the side on which the flat insulating film 103 is to be mounted. Thereafter, a flat insulating film 103 is mounted on the upper surface of the insulating layer 108. The insulating film 103 desirably has a larger area than the upper surface of the insulating layer 108.
From the viewpoint of supporting the flat insulating film 103, the insulating layer 108 is preferably mounted on the upper surface on the light receiving element side having a larger area.

  As shown in FIG. 1, the flat insulating film 103 is provided on the upper surface of the insulating layer 108 between the upper surface of the light receiving element 101 and the lower surface of the light emitting element 102. The insulating film 103 having this shape can be obtained, for example, by die cutting with a mold or the like. Therefore, the material of the insulating film 103 is preferably a material and a thickness that are transparent and can be easily cut out with a mold or the like. An example of this material is polyimide resin.

  On the other hand, as shown in FIG. 1, the lead frames 104 and 105 have a shape in which the upper surface and the lower surface of each end face each other. Furthermore, the lead frames 104 and 105 have end portions for mounting on a substrate or the like. The lead frames 104 and 105 having this shape can be obtained by etching or pressing, for example. As a material of the lead frames 104 and 105, a copper material, an iron material, or the like can be used.

An example of a method for assembling the photocoupler 100 shown in FIG. 1 will be described as an embodiment of the method for assembling a photocoupler according to the present invention with reference to FIGS.
The method of assembling the photocoupler of this embodiment includes the following steps.
(I) A step of providing a first optical element (light receiving element 101) on the upper surface of the first lead frame 104 and providing a second optical element (light emitting element 102) on the lower surface of the second lead frame 105.
(Ii) The upper surface of the light receiving element 101 is higher than the uppermost point of the bonding wire 110 connecting the upper surface of the first lead frame 104 and the upper surface of the light receiving element 101 and parallel to the upper surface of the first lead frame 104. And a step of providing the insulating portion 120 (the insulating film 103 and the insulating layer 108) having the insulating portion 120 having a distance from the first lead frame 104.
(Iii) The upper surface of the light receiving element 101 and the lower surface of the light emitting element 102 are opposed to each other with the insulating portion 120 (insulating film 103, insulating layer 108) interposed therebetween, and the insulating portion 120 is separated from the second lead frame 105. Fixing the upper surface 104 of the first lead frame and the lower surface of the second lead frame 105;
Each step of the photocoupler assembly method of this embodiment will be described.

[Step (i)]
First, lead frames 104 and 105 are prepared as attachment portions of the light receiving element 101 and the light emitting element 102 (FIG. 4A). Thereafter, the light emitting element 102 is mounted on the lower surface of the lead frame 105.
[Step (ii), (iii)]
In addition, the light receiving element 101 on which the insulating layer 108 obtained by the above-described wafer process is formed is mounted on the upper surface of the lead frame 104 (FIG. 4A ′). Subsequently, the bonding wires 110 are wired to the respective lead terminals by wire bonding (FIGS. 4B and 4B). At this time, the insulating layer 108 having a flat upper surface is provided so as to be higher than the uppermost point of the bonding wire 110 that connects the upper surface of the lead frame 104 and the upper surface of the light receiving element 101.
Next, a small amount of transparent resin (transparent silicone resin 107 is applied to the upper surface of the insulating layer 108, the insulating film 103 is mounted thereon, and the silicone resin 107 is cured (FIG. 4 (c ′)). Thus, the insulating film 103 is provided on the upper surface of the insulating layer 108 via the transparent silicone resin 107. Subsequently, the transparent silicone resin 106 is applied to the light emitting element 102 (FIG. 4C). The transparent insulating film 103 having a larger area than the upper surface of the insulating layer 108 is used.
Thereafter, the upper surfaces of the lead frame 104 and the lower surface of the lead frame 105 are completely cured and fixed so that the light emitting element 102 and the light receiving element 101 face each other with the insulating film 103 interposed therebetween. At this time, the insulating film 103 is separated from the lead frame 104 and the lead frame 105 so as not to be in direct contact (FIGS. 5 and 6A). Thereby, the optical coupling between the light receiving element 101 and the light emitting element 102 is formed.

  Next, the sealing material 109 is formed (FIG. 6B). Thereafter, unnecessary portions of the lead frame are removed and shaped into a shape as shown in FIG. Thus, the photocoupler 100 of FIG. 1 is obtained.

  The effect of this embodiment will be described. In the present embodiment, an insulating layer 108 having an upper surface parallel to the upper surface of the first lead frame 104 is provided as a support mechanism for supporting the lower surface of the flat insulating film 103 during assembly. Since the flat insulating film 103 is provided on the upper surface of the insulating layer 108, the flat insulating film 103 can be mounted on a horizontal surface, and the position of the insulating film 103 is stabilized. For this reason, it is possible to prevent the insulating film 103 from rotating or misaligned during assembly.

  Moreover, since the insulating film 103 is solid, it does not deform in the assembly process. Accordingly, since the insulating film 103 is supported by the insulating layer 108 during assembly, the position of the insulating film 103 can be stabilized without contacting the first lead frame 104 or the second lead frame 105. Further, the insulating layer 108 is simply incorporated as it is as a constituent element of the photocoupler 100. Therefore, unlike the manufacturing method of Patent Document 1, a lead that temporarily supports an insulating film is not required, so the size can be reduced, and a step of cutting the lead before resin sealing is not required. There is no concern about wire breakage.

  In addition, an insulating film 103 having a larger area than the upper surface of the insulating layer 108 is provided on the insulating layer 108 and disposed away from the lead frame 104 and the lead frame 105, so that a sufficient internal creepage distance can be obtained for insulation. A breakdown voltage is secured.

  Furthermore, in this embodiment, the insulating layer 108 has an upper surface higher than the uppermost point of the bonding wire 110. In that case, the lower surface of the insulating film 103 is formed at a position higher than the uppermost point of the bonding wire 110. For this reason, since the insulating film 103 does not touch the bonding wire 110 when the film is mounted, deformation of the wire can be prevented.

  As described above, in this embodiment, while preventing rotation and displacement of the insulating film during assembly, it prevents deformation and breakage of the wire, prevents assembly failure, and reduces the size. Is possible.

By the way, in the case of the above-described photocoupler of Patent Document 2, as shown in FIG. 11, this photocoupler includes a light receiving chip 24 formed on the upper surface of the insulating case substrate 11 and a transparent formed on the upper surface of the light receiving chip 24. The insulating layer 25 and the light emitting chip 23 formed on the upper surface of the transparent insulating layer 25 are provided.
The transparent insulating layer 25 is formed so as to protrude outward from the bottom surface of the light emitting chip 23 on the upper layer side, and a part thereof is bent so as not to interfere with the wire bonding of the light receiving chip 24 on the lower layer side.

Thus, since the transparent insulating layer 25 is bent from the lower surface of the light emitting chip 23 toward the upper surface, when the upper surface of the light emitting chip 23 is formed on the lower surface of the lead frame, the light emitting side lead frame is transparently insulated. There is a possibility that the bent portion of the layer 25 comes into contact.
For this reason, there is a concern that the dielectric breakdown voltage may decrease or the assembly yield may decrease due to the contact between the bent transparent insulating layer 25 and the light emitting side lead frame. Therefore, it is necessary to design so as not to contact the bent transparent insulating layer 25, but in this case, there is a problem that the size of the light emitting chip 23 and the light emitting side lead frame cannot be increased.

In contrast, in the present embodiment, as shown in FIG. 1, a flat insulating film 103 is provided on the upper surface of the insulating layer 108 between the upper surface of the light receiving element 101 and the lower surface of the light emitting element 102. ing.
Since this insulating film 103 is a flat plate, it is unlikely to come into contact with the light-emitting side lead frame 105 formed to face the upper surface of the insulating film 103. For this reason, a decrease in assembly yield due to this contact can be prevented. Furthermore, in this embodiment, it is possible to increase the size of the light emitting element and the light emitting side lead frame.

  The present invention is not limited to the above embodiment, and various modifications can be made. For example, as shown in FIG. 2, in the photocoupler 100 according to the modification of the present embodiment, the insulating film 103 and the insulating layer 108 that constitute the insulating portion 120 may be integrally formed. The insulating part 120 is formed on the upper surface of the light receiving element 101. In this case, the effect of this embodiment can be obtained.

  As illustrated in FIG. 3, the insulating layer 108 according to the modification of the present embodiment may include an opening 140 that is provided so as to face the lower surface of the light emitting element 102 and through which light passes. In the above-described embodiment, the insulating part 120 is entirely transparent. On the other hand, in this modification, even if the insulating layer 108 is formed of an opaque material, the opening 140 is formed as the light receiving surface on the light receiving element 101, and thus the effect of the present embodiment can be obtained. .

  The shape of the insulating layer 108 can be, for example, a rectangle or a circle when viewed from above. The shape of the opening 140 can be, for example, a rectangle or a circle when viewed from above. In the present modification, the opening 140 is provided at the corner of the insulating layer 108.

Moreover, as shown in FIG. 13, in the photocoupler 100 of the modification of this embodiment, the insulating layer 161 can be made into a cylindrical shape. The shape of the insulating layer 161 can be, for example, a rectangle or a circle when viewed from above. The shape inside the cylinder may be, for example, a rectangle or a circle when viewed from above. The peripheral portion of the insulating layer 161 (insulating film) is made of a light shielding member, while the inside of the tube is made of a transparent member. The insulating layer 161 is formed by filling a transparent resin inside the light shielding cylindrical member.
In the photocoupler 100 of the modified example, a cylindrical insulating layer 161 is provided on the light receiving element 101 (light receiving IC). At this time, the transparent region inside the cylinder of the insulating layer 161 is provided above the PD 163 (photodiode) in the light receiving element 101.

  With the above configuration, the structure of the photocoupler 100 is obtained in which the optical coupling path extends from the light emitting element 102 side to the transparent resin 107, the insulating film 162, the transparent resin inside the cylinder, and the light receiving element 101 side (FIG. 13). . For this reason, in this modified example, the same effects as those of the first embodiment can be obtained, and more stable optical coupling with less variation in shape can be formed, and variation in photosensitivity can be suppressed.

  In the above embodiment, the light receiving element 101 is mounted on the lead frame 104 and the light emitting element 102 is mounted on the lead frame 105. However, the light emitting element 102 may be mounted on the lead frame 104 and the light receiving element 101 may be mounted on the lead frame 105.

DESCRIPTION OF SYMBOLS 11 Insulation case board | substrate 16 Lead frame 19 Bonding wire 20 Insulating film 22a Support part 22b Support part 23 Light emitting chip 24 Light receiving chip 25 Transparent insulating layer 100 Photocoupler 101 Light receiving element 102 Light emitting element 103 Insulating film 104 Lead frame 105 Lead frame 106 Resin 107 Resin 108 Insulating layer 109 Sealing material 110 Bonding wire 120 Insulating part 130 Top point 140 Opening part 161 Insulating layer 162 Insulating film 163 PD (photodiode)

Claims (12)

Providing a first optical element on the top surface of the first lead frame and providing a second optical element on the bottom surface of the second lead frame;
The upper surface of the first optical element is higher than the highest point of the bonding wire connecting the upper surface of the first lead frame and the upper surface of the first optical element, and is parallel to the upper surface of the first lead frame. Providing an insulating portion having an upper surface spaced apart from the first lead frame;
The first lead frame such that an upper surface of the first optical element and a lower surface of the second optical element are opposed to each other with the insulating portion interposed therebetween, and the insulating portion is separated from the second lead frame. Fixing the upper surface of the second lead frame and the lower surface of the second lead frame;
A method of assembling a photocoupler.   The insulating portion has an insulating layer having a flat upper surface higher than the uppermost point of the bonding wire connecting the upper surface of the first lead frame and the upper surface of the first optical element, and wider than the upper surface of the insulating layer The method for assembling a photocoupler according to claim 1, comprising a transparent insulating film having an area. In the step of providing the insulating part, further applying a transparent resin on the upper surface of the insulating layer;
3. The method of assembling a photocoupler according to claim 2, further comprising the step of providing the insulating film on the upper surface of the insulating layer via the transparent resin.   4. The method of assembling a photocoupler according to claim 1, wherein the insulating portion is transparent.   4. The method of assembling a photocoupler according to claim 2, wherein the insulating layer and the insulating film are integrally formed.   6. The method of assembling a photocoupler according to claim 1, wherein the first optical element is a light receiving element. A first lead frame;
A second lead frame provided to face the upper surface of the first lead frame;
A first optical element provided on the upper surface of the first lead frame so as to face the lower surface of the second lead frame;
A second optical element provided on the lower surface of the second lead frame so as to face the upper surface of the first optical element;
A bonding wire connecting the upper surface of the first lead frame and the upper surface of the first optical element;
The first lead frame provided on the upper surface of the first optical element has an upper surface higher than an uppermost point of the bonding wire, and the first lead frame and the second lead frame are separated from each other. An insulating part having an upper surface parallel to the upper surface;
A photocoupler comprising:   The insulating portion includes an insulating layer having a flat upper surface higher than the highest point of a bonding wire connecting the upper surface of the first lead frame and the upper surface of the first optical element, and an area wider than the upper surface of the insulating layer The photocoupler according to claim 7, further comprising a transparent insulating film having the following characteristics.   The photocoupler according to claim 8, wherein the insulating film and the insulating layer are integrally formed.   10. The photocoupler according to claim 8, wherein the insulating layer has an opening through which light passes and is provided so as to face a lower surface of the second optical element.   11. The photocoupler according to claim 7, wherein one of the first optical element and the second optical element is a light emitting element and the other is a light receiving element.   The photocoupler according to claim 11, wherein the first optical element is the light receiving element.

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