JP6203479B2 - OPTICAL SEMICONDUCTOR DEVICE, MANUFACTURING METHOD THEREOF, SUBSTRATE USED FOR MANUFACTURING - Google Patents

Description

  The present invention relates to an optical semiconductor device in which a light emitting diode is bonded onto a silver plating layer formed on a surface of a substrate, a manufacturing method thereof, a base body used for the manufacturing, and a reflector molded body.

  As an optical semiconductor device on which an LED (Light Emitting Diode) is mounted, the one disclosed in Patent Document 1 is known. The optical semiconductor device described in Patent Document 1 is formed by bonding a blue LED to a molded body, raising the molded body so as to surround the blue LED, and reflecting the light emitted from the blue LED. The blue LED is sealed by filling a transparent sealing portion containing a body.

International Publication No. 2007/015426 Pamphlet

  In recent years, such optical semiconductor devices have come to be employed as LED lighting such as lighting and street lamps. However, when actually used, the illuminance of the LED illumination decreases in a shorter time than the guaranteed time of the LED. This is because a silver plating layer is formed on the electrode of the optical semiconductor device and the silver plating layer is discolored. That is, since the resin having high gas and moisture permeability is generally used for the transparent sealing portion, the silver plating layer is corroded and discolored by the gas and moisture that have passed through the transparent sealing portion. In particular, when the silver plating layer is sulfided by hydrogen sulfide gas, the electrode is changed to black, so that the illuminance is significantly reduced.

  Conventionally, a thermoplastic resin has been employed as the reflecting plate, and since the yellowing rate of the reflecting plate was faster than the sulfiding rate of the silver plating layer, the decrease in illuminance due to the sulfidation of the silver plating layer was not noticeable. However, recently, a thermosetting resin has been adopted as a reflection plate, and the yellowing rate of the reflection plate has become slower than the sulfidation rate of the silver plating layer. It has come to stand out. In addition, when the LED illumination is made high-powered, the heat generation temperature of the blue LED is increased and the temperature of the silver plating layer is increased, so that the sulfidation of the silver plating layer is promoted.

  Furthermore, in view of such problems associated with the sulfidation of the silver plating layer, there is a movement to standardize the evaluation of the hydrogen sulfide resistant gas of the optical semiconductor device adopted for the LED illumination.

  Therefore, the present inventors have conducted intensive studies and found that the silver plating layer was effectively sulfidized by covering the silver plating layer with a clay film, rather than improving the gas permeability of the transparent sealing portion. It was found that it can be suppressed.

  However, since the degree of suppression of sulfidation of the silver plating layer varies depending on the thickness of the clay film covering the silver plating layer, the present inventors have made a clay film that can sufficiently suppress sulfidation of the silver plating layer practically. Research on thickness range was repeated.

  That is, an object of the present invention is to provide an optical semiconductor device capable of suppressing the sulfidation of the silver plating layer to a practically sufficient level, a manufacturing method thereof, a substrate used for the manufacturing, and a reflector molded body.

  An optical semiconductor device according to the present invention includes a substrate having a silver plating layer formed on a surface thereof, a light emitting diode bonded on the silver plating layer, and a reflector disposed on the substrate so as to surround the light emitting diode. And a transparent sealing portion that fills the reflector and seals the light emitting diode, and a clay film that covers the silver plating layer, and the thickness of the clay film is 0.01 μm or more and 500 μm or less.

  In this optical semiconductor device, the silver plating layer is covered with a clay film, and the thickness of the clay film is in the range of 0.01 μm to 500 μm. Sulfurization can be suppressed. As a result, a decrease in illuminance of the optical semiconductor device due to blackening of the silver plating layer is suppressed.

  A substrate according to the present invention includes a substrate having a silver plating layer formed on a surface thereof, a light emitting diode bonded on the silver plating layer, a reflector disposed on the substrate and surrounding the light emitting diode, and a reflector A silver plating layer formed on the surface is covered with a clay film, which is used for manufacturing an optical semiconductor device including a transparent sealing portion that is filled in and seals the light emitting diode, and a clay film that covers the silver plating layer. The thickness of the clay film is 0.01 μm or more and 500 μm or less.

  In this substrate, the silver plating layer is covered with a clay film, and the thickness of the clay film is in the range of 0.01 μm to 500 μm. Sulfidation of the silver plating layer can be suppressed to a sufficient extent, and a decrease in illuminance of the optical semiconductor device due to blackening of the silver plating layer is suppressed.

  A reflector molded body according to the present invention includes a substrate having a silver plating layer formed on a surface thereof, a light emitting diode bonded on the silver plating layer, and a reflector disposed on the substrate so as to surround the light emitting diode. The silver plating layer formed on the surface is used for the manufacture of an optical semiconductor device including a transparent sealing portion that fills the reflector and seals the light emitting diode, and a clay film that covers the silver plating layer. A reflector molded body in which a reflector is disposed on a substrate coated with the above, and the thickness of the clay film is 0.01 μm or more and 500 μm or less.

  In this reflector molded body, the silver plating layer is covered with a clay film, and the thickness of the clay film is in the range of 0.01 μm or more and 500 μm or less. Sulfurization of the silver plating layer can be suppressed to a practically sufficient level, and a decrease in illuminance of the optical semiconductor device due to blackening of the silver plating layer is suppressed.

  An optical semiconductor device manufacturing method according to the present invention includes a substrate having a silver plating layer formed on a surface thereof, a light emitting diode bonded on the silver plating layer, and a substrate on a position surrounding the light emitting diode. A method of manufacturing an optical semiconductor device comprising a reflector, a transparent sealing portion that fills the reflector and seals the light emitting diode, and a clay film that covers the silver plating layer. A light emitting diode is disposed by bonding on a silver plating layer in the reflector after the substrate preparing step for preparing the prepared substrate, the reflector arranging step for arranging the reflector on the substrate after the substrate preparing step, and the reflector arranging step. After the light emitting diode mounting step and the light emitting diode mounting step, the light emitting diode and the silver plating layer are electrically bonded by wire bonding. A light emitting diode connecting step, a light emitting diode sealing step for sealing the light emitting diode by filling a transparent sealing portion in the reflector after the light emitting diode connecting step, and silver plating for covering the silver plating layer with a clay film Including a layer coating step, and the clay film has a thickness of 0.01 μm or more and 500 μm or less.

  In this method of manufacturing an optical semiconductor device, in the silver plating layer coating step, the silver plating layer is coated with a clay film, and the thickness of the clay film is in the range of 0.01 μm to 500 μm. Sulfidation of the silver plating layer can be suppressed to a sufficient extent, and a decrease in illuminance of the optical semiconductor device due to blackening of the silver plating layer can be significantly suppressed.

  The silver plating layer covering step is performed before the reflector placing step, after the reflector placing step, and before the light emitting diode mounting step, after the light emitting diode connecting step, and the light emitting diode. The aspect performed before a sealing process may be sufficient.

  ADVANTAGE OF THE INVENTION According to this invention, the optical semiconductor device which can suppress the sulfidation of a silver plating layer to a practically sufficient level, its manufacturing method, the base | substrate used for the manufacture, and a reflector molded object are provided.

1 is a cross-sectional view of an optical semiconductor device according to a first embodiment. FIG. 2 is a plan view of the optical semiconductor device shown in FIG. 1. FIG. 2 is a partial enlarged cross-sectional view of the optical semiconductor device shown in FIG. 1. It is a conceptual diagram for demonstrating the structure of the clay film using a montmorillonite. It is a microscope picture which shows the cross section of the clay film using a montmorillonite. 3 is a flowchart showing a method for manufacturing the optical semiconductor device according to the first embodiment. It is sectional drawing of the reflector molded object which concerns on 1st Embodiment. It is the microscope picture which showed a mode that the wire edge part pierced the viscosity film | membrane. It is sectional drawing of the optical semiconductor device which concerns on 2nd Embodiment. 6 is a flowchart illustrating a method for manufacturing an optical semiconductor device according to a second embodiment. It is sectional drawing of the base | substrate which concerns on 2nd Embodiment. It is sectional drawing of the optical semiconductor device which concerns on 3rd Embodiment. It is a top view of the optical semiconductor device shown in FIG. 6 is a flowchart showing a method for manufacturing an optical semiconductor device according to a third embodiment. It is sectional drawing which showed the mode after the silver plating layer coating process of 3rd Embodiment. It is the schematic of the test device used in the Example. It is the photograph which showed the crack which arose in the clay film in the Example.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.
[First Embodiment]

  1 and 2 show an optical semiconductor device 1A according to the first embodiment. FIG. 1 is a cross-sectional view of the optical semiconductor device 1A, and FIG. 2 is a plan view of the optical semiconductor device 1A.

  As shown in FIGS. 1 and 2, the optical semiconductor device 1 </ b> A is generally classified as a “surface mount type”. This optical semiconductor device 1 </ b> A includes a substrate 10, a blue LED 30 bonded to the surface of the substrate 10, a reflector 20 provided on the surface of the substrate 10 so as to surround the blue LED 30, and the reflector 20 filled with the blue LED 30. And a transparent sealing resin (transparent sealing portion) 40 for sealing. In addition, illustration of the transparent sealing resin 40 is abbreviate | omitted in FIG.

  The substrate 10 is an insulating substrate made of a known insulating material. A silver plating layer 14 is formed on the surface 10 a of the substrate 10 via a copper plating plate 12. The silver plating layer 14 is an electrode that is disposed on the surface of the substrate 10 and is electrically connected to the blue LED 30. The silver plating layer 14 may have any composition as long as it is a plating layer containing silver. For example, the silver plating layer 14 may be formed by plating only silver, or the silver plating layer 14 may be formed by plating nickel and silver in this order.

  Here, the copper plating plate 12 and the silver plating layer 14 are electrically insulated from each other in the insulating portion 16 with the anode E1 side and the cathode E2 side spaced apart. As shown in FIG. 1, the insulating portion 16 is a portion where neither the copper plating plate 12 nor the silver plating layer 14 is formed. Note that a known insulating material may be disposed on the insulating portion 16 as necessary.

  The blue LED 30 is die-bonded to the silver plating layer 14 on the cathode E2 side, and is electrically connected to the silver plating layer 14 via the die-bonding material 32. The blue LED 30 is wire-bonded to the silver plating layer 14 on the anode E1 side, and is electrically connected to the silver plating layer 14 through the bonding wire 34. The anode E1 and the cathode E2 can be exchanged as necessary.

  The reflector 20 is filled with a transparent sealing resin 40 for sealing the blue LED 30 and reflects light emitted from the blue LED 30 to the surface side of the optical semiconductor device 1A.

  The reflector 20 is erected from the surface of the substrate 10 so as to surround the blue LED 30. That is, the reflector 20 has an inner space that rises in the thickness direction of the substrate 10 so as to surround the blue LED 30 and accommodates the blue LED 30 inside, and is formed in a circular shape in plan view (see FIG. 2). A peripheral surface 20a is provided. Although the shape of the inner peripheral surface 20a is not particularly limited, it is preferably formed in a truncated cone shape (funnel shape) whose diameter increases as the distance from the substrate 10 increases, from the viewpoint of improving the illuminance of the optical semiconductor device 1A. In the drawing, as an example of forming the inner peripheral surface 20a, the lower part located on the substrate 10 side is perpendicular to the substrate 10, and the upper part located on the opposite side of the substrate 10 is separated from the substrate 10. An enlarged diameter is shown.

  The reflector 20 is made of a cured product of a thermosetting resin composition containing a white pigment. From the viewpoint of ease of forming the reflector 20, the thermosetting resin composition is preferably one that can be pressure-molded at room temperature (25 ° C.) before thermosetting.

  As the thermosetting resin contained in the thermosetting resin composition, various resins such as an epoxy resin, a silicone resin, a urethane resin, and a cyanate resin can be used. In particular, an epoxy resin is preferable because of its excellent adhesion to various materials.

  As the white pigment, alumina, magnesium oxide, antimony oxide, titanium oxide, or zirconium oxide can be used. Among these, titanium oxide is preferable from the viewpoint of light reflectivity. Inorganic hollow particles may be used as the white pigment. Specific examples of the inorganic hollow particles include sodium silicate glass, aluminum silicate glass, borosilicate soda glass, and shirasu.

  The transparent sealing resin 40 fills the inner space formed by the inner peripheral surface 20 a of the reflector 20 and seals the blue LED 30. The transparent sealing resin 40 is made of a transparent sealing resin having translucency. The transparent sealing resin includes a translucent resin as well as a completely transparent resin. The transparent sealing resin preferably has an elastic modulus of 1 MPa or less at room temperature (25 ° C.). In particular, it is preferable to employ a silicone resin or an acrylic resin from the viewpoint of transparency. The transparent sealing resin contains an inorganic filler that diffuses light and a phosphor 42 that emits white light using blue light emitted from the blue LED 30 as an excitation source.

  In the optical semiconductor device 1 </ b> A according to the present embodiment, the silver plating layer 14 in the reflector 20 is covered with the clay film 50. That is, as shown in FIG. 3, the reflector 20 has a laminated structure in which the copper plating plate 12, the silver plating layer 14, and the clay film 50 are sequentially laminated from the bottom in the substrate thickness direction.

  The clay film 50 suppresses the sulfidation of the silver plating layer 14 by covering the lower silver plating layer 14. As the clay constituting the clay film 50, any of natural clay and synthetic clay can be used, and any one or more of stevensite, hectorite, saponite, montmorillonite and beidellite can be used.

  4 and 5 show a clay film 50 composed of natural clay montmorillonite. As can be seen from these figures, scaly clay pieces (nanofillers) are randomly overlapped by several tens of layers. A gas path route like a maze is formed in the clay film 50.

  That is, the clay film 50 covering the silver plating layer 14 extends the path route to the silver plating layer 14, thereby effectively preventing gas such as hydrogen sulfide gas from reaching the silver plating layer 14. Further, sulfidation of the silver plating layer 14 is significantly suppressed. In particular, montmorillonite has a high gas barrier property when used for the clay film 50 because the thickness H of the clay piece is 1 nm or less, the length L is 10 nm to 400 nm and the aspect ratio is high and the gas path route is long. Can be realized.

  The thickness d of the clay film 50 is in the range of 0.01 μm to 500 μm. Here, when the film thickness d is 0.01 μm or more, sulfidation of the silver plating layer can be suppressed, and blackening of the silver plating layer is suppressed. Even when the film thickness d is 500 μm or less, in the step of forming the clay film (more specifically, the step of drying a clay diluted solution described later), a situation in which a crack occurs in the clay film is avoided. Sulfurization is suppressed. When cracks occur, the gas reaches the silver plating layer directly from the cracks without passing through the above-mentioned path route, so that the effect of suppressing sulfidation is remarkable at the cracked part of the clay film. It will decline.

  Therefore, by designing the film thickness d of the clay film 50 in a thickness range of 0.01 μm or more and 500 μm or less, it is possible to achieve a practically sufficiently high gas barrier property for the silver plating layer 14. Moreover, the gas barrier property with respect to the silver plating layer 14 and the transparency of the clay film 50 can be made compatible.

  As described above, in the optical semiconductor device 1A, the silver plating layer 14 is covered with the clay film 50, and the thickness of the clay film 50 is in the range of 0.01 μm to 500 μm. The illuminance reduction of the optical semiconductor device 1A due to the blackening of the silver plating layer 14 is suppressed.

  Next, a method for manufacturing the optical semiconductor device 1A according to the first embodiment will be described.

  FIG. 6 is a flowchart showing a method for manufacturing the optical semiconductor device 1A according to the first embodiment. As shown in FIG. 6, in the manufacturing method of the optical semiconductor device 1A, first, as a substrate preparation step, an insulating substrate 10 having a copper plated plate 12 wired on the surface is prepared (step S101), and a copper plated plate is prepared. The silver plating layer 14 is formed on the surface of 12, and the board | substrate 10 with which the silver plating layer 14 was formed through the copper plating board 12 is formed (step S102).

  Next, as a reflector arranging step, the reflector 20 is formed on the substrate 10 so as to surround the region where the blue LED 30 is to be mounted (step S103). And as a silver plating layer coating process, the silver plating layer 14 in the reflector 20 is coat | covered with the clay film 50 (step S104).

  More specifically, the silver plating layer coating step is composed of a step of applying a clay diluent and a step of drying the clay diluent.

  In the step of applying the clay diluent, the clay diluent is applied to the silver plating layer 14 in the reflector 20, and the silver plating layer 14 is covered with the clay diluent. The clay diluent is a liquid obtained by diluting clay with a solvent. Although it does not restrict | limit especially as an aqueous solvent, For example, liquids, such as water, ethanol, methanol, isopropyl alcohol (henceforth "IPA"), a dioxane, can be employ | adopted individually or in mixture of multiple. it can.

  The clay dilution liquid may be applied by, for example, dropping or spraying the clay dilution liquid onto the inner space of the reflector 20 from the surface side of the substrate 10. At this time, the dripping amount or the spraying amount of the clay diluent is adjusted so that at least the entire silver plating layer 14 is covered with the clay diluent.

  In the step of drying the clay diluted solution, the clay diluted solution applied to the silver plating layer 14 is dried to form the clay film 50. At this time, the film thickness d of the clay film 50 is adjusted to a thickness range of 0.01 μm to 500 μm. The thickness of the clay film 50 can be adjusted, for example, by changing the concentration of the clay diluent or increasing / decreasing the amount of the clay diluent applied.

  The film thickness d of the clay film 50 is preferably 0.01 μm or more and 500 μm or less, preferably 0.03 μm or more and 500 μm or less, more preferably 0.05 μm or more and 100 μm or less, and 0.05 μm or more. More preferably, it is 10 μm or less, 0.05 μm or more and 1 μm or less.

  By setting the film thickness d of the clay film 50 to 0.01 μm or more and 500 μm or less, the gas barrier property with respect to the silver plating layer 14 and the transparency of the clay film 50 can both be achieved. In this case, this effect can be further improved by setting the film thickness d of the clay film 50 to 0.03 to 500 μm, 0.05 to 100 μm, 0.05 to 10 μm, 0.05 to 1 μm. Can do.

  As a result, a reflector molded body 60 as shown in FIG. 7 is formed. In this reflector molded body 60, the reflector 20 is disposed on the substrate 10 on which the silver plating layer 14 is formed, and the clay film 50 is formed on the entire surface of the substrate 10 exposed from the reflector 20. That is, the entire surface region of the silver plating layer 14 and the entire region of the insulating portion 16 in the reflector 20 are covered with the clay film 50.

  Returning to FIG. 6, after the silver plating layer covering step (step S104), as a light emitting diode mounting step, the blue LED 30 is disposed on the silver plating layer 14 in the reflector 20 by bonding (step S105).

  In the light emitting diode mounting step, the blue LED 30 is die-bonded to the silver plating layer 14 on the cathode E2 side in the inner space surrounded by the reflector 20. Accordingly, the blue LED 30 is electrically connected to the silver plating layer 14 on the cathode E2 side through the die bonding material 32, and the blue LED 30 is surrounded by the reflector 20 and accommodated in the inner space.

  Next, as a light emitting diode connection step, the blue LED 30 and the silver plating layer 14 are electrically connected by wire bonding (step S106).

  In the light emitting diode connection step, the blue LED 30 and the silver plating layer 14 on the anode E1 side are wire-bonded. At this time, electrical connection between the blue LED 30 and the silver plating layer 14 is achieved by bonding the end 34 a of the wire 34 to the silver plating layer 14 so as to break through the clay film 50 covering the silver plating layer 14. According to experiments conducted by the inventors, it has been observed that the wire end 34a penetrates the clay film 50 and reaches the silver plating layer 14 as shown in the micrograph shown in FIG. Conductivity with the silver plating layer 14 is confirmed.

  Note that the breakage of the clay film 50 by the wire 34 is performed, for example, by adjusting the layer thickness of the clay film 50, adjusting the load of the bonding head that performs wire bonding, or vibrating the bonding head. .

  Returning to FIG. 6 again, after the light emitting diode connection step (step S106), as the light emitting diode sealing step, the inner space formed by the inner peripheral surface 20a of the reflector 20 is filled with the transparent sealing resin 40, The blue LED 30 is sealed with the transparent sealing resin 40 (step S107).

  The optical semiconductor device 1A shown in FIGS. 1 and 2 is manufactured by the manufacturing method described above.

In the first embodiment described above, the clay film 50 that covers the entire surface of the silver plating layer 14 can be easily formed by, for example, dropping a clay diluted solution to be the clay film 50 into the reflector 20. Simplification of the process is achieved. In addition, since the clay film 50 is not interposed between the substrate 10 and the reflector 20, high adhesion between the substrate 10 and the reflector 20 is realized.
[Second Embodiment]

  Next, an optical semiconductor device 1B according to the second embodiment will be described with reference to FIGS. The optical semiconductor device 1B according to the second embodiment is different from the above-described optical semiconductor device 1A according to the first embodiment only in the form of the clay film, and the other configurations are the same.

  That is, as shown in FIG. 9, in the optical semiconductor device 1 </ b> B according to the second embodiment, the clay film 50 is formed not only on the silver plating layer 14 in the reflector 20 but also on the silver plating layer 14 on the substrate 10. It is formed over the entire surface.

  A method for manufacturing the optical semiconductor device 1B according to the second embodiment will be described below. Only parts different from the method of manufacturing the optical semiconductor device 1B according to the second embodiment will be described, and description of the same or similar parts will be omitted.

  FIG. 10 is a flowchart showing a method for manufacturing the optical semiconductor device 1B according to the second embodiment.

  As shown in FIG. 10, in the method of manufacturing the optical semiconductor device 1B, first, the substrate preparation process (steps S201 and S202) is performed in the same manner as the substrate preparation process of the first embodiment.

  Next, as a silver plating layer coating step, the entire surface of the silver plating layer 14 formed on the substrate 10 is covered with the clay film 50 (step S203).

  As a result, a base body 70 as shown in FIG. 11 is formed. In the substrate 70, the upper surface of the substrate 10 is entirely covered with the clay film 50. That is, the entire surface region of the silver plating layer 14 and the entire region of the insulating portion 16 are covered with the clay film 50.

  Subsequently, the reflector forming step (step S204), the light emitting diode mounting step (step S205), the light emitting diode connecting step (step S206), and the light emitting diode sealing step (step S207) are performed in this order. The reflector forming process (step S204), the light emitting diode mounting process (step S205), the light emitting diode connecting process (step S206), and the light emitting diode sealing process (step S207) in the second embodiment are the same as those in the first embodiment. This is the same as the reflector forming step (step S103), the light emitting diode mounting step (step S105), the light emitting diode connecting step (step S106), and the light emitting diode sealing step (step S107).

  Also in the optical semiconductor device 1B of the second embodiment described above, the silver plating layer 14 is covered with the clay film 50 as in the optical semiconductor device 1A of the first embodiment. Since the thickness is in the range of 0.01 μm or more and 500 μm or less, a decrease in illuminance of the optical semiconductor device 1B due to blackening of the silver plating layer 14 is suppressed.

In the second embodiment described above, since the clay dilution liquid to be the clay film 50 is applied to the entire surface of the substrate 10, it is not necessary to align the reflector with respect to the application, thereby simplifying the manufacturing process. It has been. Further, burrs are generated at the reflector-silver interface portion of the reflector 20 due to the protrusion from the mold during the melting process of the reflector molding resin, but in this embodiment, the burrs can be reduced.
[Third Embodiment]

  Next, an optical semiconductor device 1C according to the third embodiment will be described with reference to FIGS. The optical semiconductor device 1C according to the third embodiment is different from the above-described optical semiconductor device 1A according to the first embodiment only in the form of the substrate and the clay film, and the other configurations are the same.

  That is, as shown in FIG. 12, in the optical semiconductor device 1C according to the third embodiment, a conductive substrate 13 such as a lead frame is used instead of the substrate 10 on which the copper plating plate is wired. In order to insulate the silver plating layer 14 on the anode E1 side and the silver plating layer 14 on the cathode E2 side, an insulating portion 17 penetrating the substrate 13 in the thickness direction is provided. In the first embodiment and the second embodiment, the substrate 10 on which the copper plating plate is wired may be changed to the substrate 13 as appropriate.

  In addition, the clay film 50 of the optical semiconductor device 1C according to the third embodiment is formed so as to integrally cover the silver plating layer 14 in the reflector 20 and the blue LED 30 mounted on the silver plating layer 14. ing.

  A method for manufacturing the optical semiconductor device 1C according to the third embodiment will be described below. Only parts different from the method of manufacturing the optical semiconductor device 1C according to the third embodiment will be described, and description of the same or similar parts will be omitted.

  FIG. 14 is a flowchart illustrating a method for manufacturing the optical semiconductor device 1C according to the third embodiment.

  As shown in FIG. 14, in the manufacturing method of the optical semiconductor device 1C, first, as a substrate preparation step, the conductive substrate 13 is prepared (step S301), and the silver plating layer 14 is formed on the surface of the substrate 13, The substrate 13 on which the silver plating layer 14 is formed is formed (step S302).

  Subsequently, the reflector forming step (step S303) and the light emitting diode mounting step (step S304) are performed in this order. The reflector forming process (step S303) and the light emitting diode mounting process (step S304) in the third embodiment are the same as the reflector forming process (step S103) and the light emitting diode mounting process (step S105) in the first embodiment. It is.

  Next, as a silver plating layer coating process, as shown in FIG. 15, the silver plating layer 14 in the reflector 20 and the blue LED 30 mounted on the silver plating layer 14 are integrally covered with a clay film 50 ( Step S305).

  Further, the light emitting diode connecting step (step S306) and the light emitting diode sealing step (step S307) are performed in this order. The light emitting diode connecting step (step S306) and the light emitting diode sealing step (step S307) in the third embodiment are the light emitting diode connecting step (step S106) and the light emitting diode sealing step (step in step S307) in the first embodiment. This is the same as S107).

  In the light emitting diode connection process of the third embodiment, when the blue LED 30 and the silver plating layer 14 on the anode E1 side are wire-bonded, the clay film 50 covered with the blue LED 30 and the silver plating layer 14 is broken through. Further, both ends 34 a and 34 b of the wire 34 are bonded to the blue LED 30 and the silver plating layer 14. Thereby, conduction between the blue LED 30 and the silver plating layer 14 is achieved.

  Also in the optical semiconductor device 1C of the third embodiment described above, the silver plating layer 14 is covered with the clay film 50 as in the optical semiconductor device 1A of the first embodiment and the optical semiconductor device 1B of the second embodiment. Moreover, since the thickness of the clay film 50 is in the range of 0.01 μm or more and 500 μm or less, a decrease in illuminance of the optical semiconductor device 1C due to the blackening of the silver plating layer 14 is suppressed.

  In the third embodiment described above, since all the elements in the reflector 20 are integrally covered with the clay film 50, the clay film 50 effectively suppresses the sulfidation of the silver plating layer 14. Moreover, in this embodiment, since the structure which a clay film touches a reflector, silver, and LED surface is possible, integration with the fluorescent substance 42 is possible, and it was mixing with transparent sealing resin conventionally. There is an advantage that the amount of the phosphor can be reduced or eliminated, or the phosphor can be localized and the concentration can be increased.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment.

  For example, the blue LED 30 that generates blue light has been described as the light emitting diode that is bonded to the optical semiconductor devices 1A, 1B, and 1C. However, a light emitting diode that generates light other than blue may be used. .

  Hereinafter, in order to clarify the relationship between the film thickness of the clay film covering the silver plating layer and the prevention of sulfidation of the silver plating, examples performed by the inventors will be described.

  First, an LED lead frame (OP4 manufactured by Enomoto Co., Ltd.) was prepared as a substrate, and four samples A to D having different clay film thicknesses were prepared. Specifically, 3 μl of clay diluted solution is dropped on a silver plating layer formed on the LED lead frame with a micropipette, dried at 70 ° for 5 minutes or more in a thermostatic bath or a hot plate, and further at 30 ° at 30 °. 4 samples A (film thickness 0.005 μm), sample B (film thickness 0.01 μm), sample C (film thickness 500 μm), and sample D (film thickness 2000 μm) with different clay film thicknesses after drying for a minute. Obtained. The thickness of the clay film was adjusted by changing the concentration of the clay dilution when each sample was prepared.

  Then, each of the samples A to D was exposed to a sulfide gas atmosphere by the tester 80 shown in FIG. Specifically, the sample 81 is placed on a stainless steel wire mesh 83 in a sealable glass bottle 82 so as to face upward, and an aluminum cup 85 in which sulfur powder 84 (about 0.5 g) is placed below the sample 81. And exposed to sulfur gas atmosphere at 80 ° for 4 hours.

  And the presence or absence of sulfidation (namely, blackening) of a silver plating layer was confirmed visually.

The results were as shown in Table 1 below.

  That is, in Samples B and C, no sulfidation of the silver plating layer was confirmed, whereas in Samples A and D, the silver plating layer was sulfided and blackened. Furthermore, in Sample D, as shown in FIG. 17, a large crack (a portion that looks black in the figure) was confirmed in the clay film.

  In the sample A having a film thickness of 0.005 μm, the clay film is too thin, so that the effect of extending the gas path route is not sufficiently obtained, and the silver plating layer is considered to be sulfided.

  In Sample D where the clay film thickness was 2000 μm, although the clay film was sufficiently thick, it was considered to have cracked because it was too thick, and gas invaded from the cracked part, and the silver plating layer was sulphurized. .

  On the other hand, in the samples B and C where the film thickness of the clay film was in the range of 0.01 μm or more and 500 μm or less, the film thickness was in an appropriate range, so that the sulfidation of the silver plating layer was effectively suppressed it is conceivable that.

  That is, from the above results, it is clear that the sulfidation of the silver plating layer can be practically sufficiently suppressed by setting the thickness of the clay film covering the silver plating layer to a range of 0.01 μm to 500 μm.

  DESCRIPTION OF SYMBOLS 1A, 1B, 1C ... Optical semiconductor device 10, 13 ... Board | substrate, 12 ... Copper plating board, 14 ... Silver plating layer, 20 ... Reflector, 30 ... Blue LED (blue light emitting diode), 32 ... Die-bonding material, 34 ... Bonding Wire: 40 ... Transparent sealing resin, 42 ... Phosphor, 50 ... Clay film, 60 ... Reflector molding, 70 ... Base.

Claims (7)

A substrate having a silver plating layer formed on the surface;
A light emitting diode bonded on the silver plating layer;
A reflector disposed on the substrate and surrounding the light emitting diode;
A transparent sealing portion that fills the reflector and seals the light emitting diode;
A clay film covering the silver plating layer,
An optical semiconductor device, wherein the clay film has a thickness of 0.01 μm or more and 500 μm or less. A substrate having a silver plating layer formed on the surface;
A light emitting diode bonded on the silver plating layer;
A reflector disposed on the substrate and surrounding the light emitting diode;
A transparent sealing portion that fills the reflector and seals the light emitting diode;
Used for the production of an optical semiconductor device comprising a clay film covering the silver plating layer,
The silver plating layer formed on the surface is a substrate coated with the clay film,
The base | substrate whose thickness of the said clay film is 0.01 micrometer or more and 500 micrometers or less. A substrate having a silver plating layer formed on the surface;
A light emitting diode bonded on the silver plating layer;
A reflector disposed on the substrate and surrounding the light emitting diode;
A transparent sealing portion that fills the reflector and seals the light emitting diode;
Used for the production of an optical semiconductor device comprising a clay film covering the silver plating layer,
A reflector molded body in which the reflector is disposed on a substrate on which the silver plating layer formed on the surface is coated with the clay film,
A reflector molded body, wherein the clay film has a thickness of 0.01 μm or more and 500 μm or less. A substrate having a silver plating layer formed on the surface;
A light emitting diode bonded on the silver plating layer;
A reflector disposed on the substrate and surrounding the light emitting diode;
A transparent sealing portion that fills the reflector and seals the light emitting diode;
A method for manufacturing an optical semiconductor device comprising a clay film covering the silver plating layer,
A substrate preparation step of preparing a substrate having a silver plating layer formed on the surface;
A reflector placement step of placing the reflector on the substrate after the substrate preparation step;
After the reflector placement step, a light emitting diode mounting step for placing the light emitting diode on the silver plating layer in the reflector by bonding;
After the light emitting diode mounting step, a light emitting diode connection step of electrically connecting the light emitting diode and the silver plating layer by wire bonding;
After the light emitting diode connection step, a light emitting diode sealing step of sealing the light emitting diode by filling the reflector with a transparent sealing portion;
A silver plating layer coating step of coating the silver plating layer with a clay film,
The manufacturing method of an optical semiconductor device whose thickness of the said clay film is 0.01 micrometer or more and 500 micrometers or less.   The method for manufacturing an optical semiconductor device according to claim 4, wherein the silver plating layer covering step is performed before the reflector arranging step.   The method for manufacturing an optical semiconductor device according to claim 4, wherein the silver plating layer covering step is performed after the reflector arranging step and before the light emitting diode mounting step.   The method for manufacturing an optical semiconductor device according to claim 4, wherein the silver plating layer covering step is performed after the light emitting diode connecting step and before the light emitting diode sealing step.