JP7116308B2 - METAL MATERIAL FOR OPTO-SEMICONDUCTOR DEVICE, MANUFACTURING METHOD THEREOF, AND OPTO-SEMICONDUCTOR DEVICE USING THE SAME - Google Patents

Description

The present invention relates to a metal material for optical semiconductor devices, a method for producing the same, and an optical semiconductor device using the same.

Light that includes a semiconductor light emitting device (hereinafter also referred to as a “light emitting device”) such as a light emitting diode (hereinafter also referred to as “LED”) or a laser diode (hereinafter also referred to as “LD”) 2. Description of the Related Art Semiconductor devices are used, for example, for vehicles, for general lighting, as backlights for liquid crystal display devices, and as light sources for projectors and the like.

2. Description of the Related Art An optical semiconductor device employs a lead frame or substrate having a surface plated with silver or a silver alloy having a high reflectance with respect to light emitted from a light emitting element. However, silver or silver alloys are easily sulfurized by sulfides, discoloration due to sulfuration, and a decrease in reflectance. Patent Literature 1 or 2 discloses an optical semiconductor device having a substrate having a surface plated with gold, which has a lower reflectance than silver but is more resistant to sulfurization than silver. 2. Description of the Related Art An optical semiconductor device provided with a lead frame or a substrate having gold or a gold alloy on its surface is used, for example, as a vehicle-mounted optical semiconductor device that requires high reliability.

JP-A-2003-347596 JP 2006-093365 A

However, gold has low adhesion to resin materials. If the adhesion between the gold plating applied to the surface of the lead frame or the substrate and the resin material for sealing or the resin material for the molding constituting the package of the optical semiconductor device is low, for example, the optical semiconductor device may be damaged in the circuit. When reflow mounting is performed on a board, the reflowed solder may penetrate from the interface between the gold plating and the member made of the resin material, causing problems such as short circuits. In addition, depending on the type of resin used for the resin material, it may melt due to the heat during reflow, causing problems such as leakage of the melted resin material from the interface between the gold plating and the resin material.
Accordingly, an object of one embodiment of the present invention is to provide a metal material for an optical semiconductor device with improved adhesion to a resin material, a method for manufacturing the same, and an optical semiconductor device using the same.

A metal material for an optical semiconductor device according to an embodiment of the present invention has a nickel or nickel alloy plating layer on a conductive substrate, a thickness of 0.01 μm or more and 0.5 μm or less, and a gold content of 80 and a layer of gold-silver alloy plating of not less than 95% by mass and not more than 95% by mass in this order.

An optical semiconductor device according to an embodiment of the present invention is an optical semiconductor device in which a light-emitting element is mounted on a lead frame or substrate made of the metal material for optical semiconductor devices.

A method for producing a metal material for an optical semiconductor device according to an embodiment of the present invention comprises the steps of forming a layer of nickel or nickel alloy plating on a conductive substrate, and optionally rhodium, palladium, rhodium alloy or forming a palladium alloy plating layer; forming a gold-silver alloy plating layer having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80% by mass or more and 95% by mass or less; in that order.

According to one embodiment of the present invention, it is possible to provide a metal material for an optical semiconductor device with improved adhesion to a resin material, a method for producing the same, and an optical semiconductor device using the same.

FIG. 1A is a schematic plan view showing an optical semiconductor device according to one embodiment. FIG. 1B is a schematic cross-sectional view of the optical semiconductor device of FIG. 1A. FIG. 2A is a schematic cross-sectional view of part of a metal material for an optical semiconductor device according to one embodiment. FIG. 2B is a schematic cross-sectional view of part of a metal material for an optical semiconductor device according to another embodiment. FIG. 3A is a schematic perspective view showing an optical semiconductor device according to another embodiment. FIG. 3B is a schematic cross-sectional view of the optical semiconductor device of FIG. 3A. FIG. 4A is a schematic cross-sectional manufacturing process diagram for explaining the manufacturing method of the optical semiconductor device. FIG. 4B is a schematic cross-sectional manufacturing process diagram for explaining the manufacturing method of the optical semiconductor device. FIG. 4C is a schematic cross-sectional manufacturing process diagram for explaining the manufacturing method of the optical semiconductor device. FIG. 4D is a schematic cross-sectional manufacturing process diagram for explaining the manufacturing method of the optical semiconductor device.

Hereinafter, embodiments of the invention will be described with reference to the drawings as appropriate. However, the metal material for an optical semiconductor device, the manufacturing method thereof, and the optical semiconductor device using the same described below are examples for embodying the technical idea of the present invention, and unless otherwise specified, , the present invention is not limited to the following embodiments. Also, the composition of the plating solution and the plating operation conditions described in the embodiment are examples. In addition, the contents described in the embodiment can also be applied to other embodiments. The sizes and positional relationships of members shown in the drawings may be exaggerated for clarity of explanation. In addition, in the following description, the same names or symbols basically indicate the same or homogeneous members, and detailed description will be omitted as appropriate.

Embodiment 1
1. Optical Semiconductor Device FIGS. 1A and 1B show the structure of an optical semiconductor device 100 of Embodiment 1. FIG. The optical semiconductor device 100 of the present embodiment includes a light emitting element 2 which is rectangular in plan view, and a lead frame 10 (hereinafter also simply referred to as "lead frame 10") made of a pair of plate-shaped metal materials 1 for optical semiconductor devices. ) and a resin molding 3 in which a part of the lead frame 10 is embedded.

The resin molding 3 is made of a resin composition containing a thermoplastic resin or a thermosetting resin. The resin molding 3 has a recess having a bottom surface and a side surface. The bottom surface of the recess is formed of a part of the pair of lead frames 10, and the side surface is formed with a reflecting surface 31 having a predetermined inclination angle. there is The space between the pair of lead frames 10 is filled with the resin composition forming the resin molded body 3 to form a part 32 of the bottom surface of the resin molded body 3 . The resin molded body 3 has a laterally long shape in plan view. The resin molded body 3 has a laterally elongated recess in its side surface with the lead frame 10 exposed at the bottom. Portions of the pair of plate-like lead frames 10 are exposed as external terminal portions on the outer surface of the resin molded body 3 , and the external terminal portions are bent along the lower surface of the resin molded body 3 . The light emitting element 2 is mounted on one of a pair of lead frames 10 forming the bottom surface of the recess. The light emitting element 2 is covered with a sealing member 5 . The sealing member 5 includes, for example, a phosphor that converts the wavelength of light from the light emitting element 2 and a sealing material. The encapsulating material preferably contains a translucent resin. The phosphor is excited by the light from the light emitting element 2, wavelength-converts the light from the light emitting element 2, and emits light having at least one emission peak wavelength within a specific wavelength range. The light emitting element 2 has a pair of positive and negative electrodes, which are electrically connected to a pair of lead frames 10 via wires 6, respectively. Through the pair of lead frames 10, the optical semiconductor device 100 can emit light by receiving power supply from the outside. The lead frame 10 or substrate made of a metal material for an optical semiconductor device, which will be described later in the embodiments, has a portion that contacts a member formed using a resin material, such as the resin molding 3 or the sealing member 5. . As used herein, a resin material refers to a material containing at least resin. The resin material includes, for example, a resin composition containing a resin.

Embodiment 2
2. Metallic Material for Optical Semiconductor Device FIG. 2A is a schematic cross-sectional view showing an embodiment of a metallic material 1 for an optical semiconductor device that constitutes a lead frame 10 or a substrate.
The metal material 1 for an optical semiconductor device includes, for example, a conductive substrate 1a made of a copper alloy, a nickel or nickel alloy plating layer 1b on the substrate 1a, a thickness of 0.01 μm or more and 0.5 μm or less, and a gold content of and a gold-silver alloy plating layer 1d containing 80% by mass or more and 95% by mass or less of in this order.

A lead frame 10 made of the metal material 1 for an optical semiconductor device serves as a mounting member for mounting the light emitting element 2, a reflecting member for reflecting light emitted from the light emitting element 2, and a conductive member electrically connected to the light emitting element 2. also has the function of Furthermore, the lead frame 10 may also function as a heat radiating member that radiates heat generated from the light emitting element 2 . The lead frame 10 made of the metal material 1 for an optical semiconductor device may be provided below the light emitting element 2 as in the first embodiment, or may be provided in the shape of a reflector surrounding the light emitting element 2 . Also, the lead frame 10 may be a plate-like lead frame. The metal material 1 for an optical semiconductor device may be used as wiring formed on an insulating substrate.

In addition, since the metal material 1 for an optical semiconductor device has the gold-silver alloy plating layer 1d having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80 mass % or more and 95 mass % or less on the surface layer, Adhesiveness is good, and in the optical semiconductor device 100, for example, the adhesiveness with the sealing member 5 and the resin molding 3 can be improved. Since the lead frame 10 made of the metal material 1 for an optical semiconductor device has high adhesiveness to a resin material, in the process of solder reflow mounting the optical semiconductor device 100 using this lead frame 10 to a printed circuit board, the solder does not interfere with the optical semiconductor device. It is possible to prevent the sealing material (hereinafter sometimes referred to as “sealing resin”) from entering inside and from leaking out of the resin molded body 3 .

Furthermore, since the metal material 1 for an optical semiconductor device has the gold-silver alloy plating layer 1d having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80 mass % or more and 95 mass % or less on the surface layer, sulfuration or oxidation It is possible to suppress discoloration due to discoloration due to discoloration by sulfurization or discoloration due to oxidation, thereby suppressing a decrease in luminous flux and maintaining a high luminous flux.

As shown in FIG. 2A, the metal material 1 for an optical semiconductor device is provided with a nickel or nickel alloy plating layer 1b and a thickness of 0.5 mm on a pair of two surfaces facing each other with the substrate 1a as the center. and a gold-silver alloy plated layer 1d having a gold content of 80% by mass to 95% by mass, in this order. The metal material 1 for an optical semiconductor device is provided with a nickel or nickel alloy plated layer 1b and, if necessary, a nickel or nickel alloy plating layer 1b, which will be described later, so as to wrap around the substrate 1a on two pairs of four surfaces facing each other with the plate-shaped substrate 1a as the center. Rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c and gold/silver alloy plating layer 1d having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80 mass % or more and 95 mass % or less in this order. may be A pair of two opposing surfaces of the plate-like substrate 1a may be referred to as a top surface or a bottom surface, and the other two opposing surfaces of the plate-like substrate 1a may be referred to as side surfaces.

The metal material 1 for an optical semiconductor device preferably has a reflectance of 25% or more and 45% or less for light having an emission peak wavelength of 450 nm. The reflectance of the metal material for optical semiconductor devices is more preferably 26% or more and 44% or less, and still more preferably 26% or more and 43% or less.
The surface of the metal material 1 for an optical semiconductor device is covered with a gold-silver alloy plating layer 1d having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80 mass % or more and 95 mass % or less. The reflectance of a metal material for an optical semiconductor device to light having an emission peak wavelength of 450 nm varies mainly depending on the gold content of the surface gold-silver alloy plating layer. When the reflectance of the metal material for optical semiconductor devices is less than 25%, it indicates that the gold content is high, and when the reflectance exceeds 45%, it indicates that the gold content is low. If the reflectance of the optical semiconductor device metal material is 25% or more and 45% or less, the adhesion between the lead frame made of the resin material and the optical semiconductor device metal material is improved, and in the process of solder reflow mounting the optical semiconductor device. , it is possible to suppress the intrusion of solder into the optical semiconductor device and the leakage of the sealing material to the outside. Further, when the reflectance of the metal material 1 for an optical semiconductor device is 25% or more and 45% or less, sulfuration can be suppressed and the luminous flux can be maintained.

The metal material 1 for an optical semiconductor device preferably has a chromaticity represented by b ^* value in the L ^* a ^* b ^* color system of 20 or more and 30 or less. The chromaticity represented by the b ^* value of the metal material 1 for an optical semiconductor device is more preferably 21 or more and 28 or less, and still more preferably 21 or more and 27 or less. The surface of the metal material 1 for an optical semiconductor device is covered with a gold-silver alloy plating layer ^1d having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80% by mass or more and 95% by mass or less. The chromaticity represented by the b ^* value in the ^* b ^* color system varies mainly depending on the content of gold in the gold-silver alloy plating layer 1d. If the b ^* value is in the range of 20 or more and 30 or less, the metal material 1 for an optical semiconductor device has good adhesion to the resin. The optical semiconductor device 100 using the lead frame made of the metal material 1 for an optical semiconductor device has good adhesion to the sealing member 5 or the resin molded body 3, and in the process of solder reflow mounting the optical semiconductor device, the solder is removed. Intrusion into the optical semiconductor device and leakage of the sealing material to the outside can be suppressed. Further, when the b ^* value in the L ^* a ^* b ^* color system of the metal material 1 for an optical semiconductor device is 20 or more and 30 or less, sulfuration can be suppressed and the luminous flux can be maintained. When the b ^* value in the L ^* a ^* b ^* color system of the metal material 1 for an optical semiconductor device is less than 20, it indicates that the gold content in the gold-silver alloy plating layer 1d is low, and the b ^* value is 30. , it indicates that the content of gold in the gold-silver alloy plating layer 1d is high.

Gold-silver alloy plating layer 1d
The gold-silver alloy plating layer 1d is provided on the surface of the metal material 1 for optical semiconductor devices. The thickness of the gold-silver alloy plating layer 1d is 0.01 μm or more and 0.5 μm or more, preferably 0.02 μm or more and 0.4 μm or less. When the thickness of the gold-silver alloy plating layer 1d is reduced to less than 0.01 μm, the adhesion with the resin material is lowered, and the optical semiconductor device 100 using the metal material 1 for optical semiconductor devices as a lead frame or substrate cannot be sealed. Adhesion between the member 5 and the resin molding material 3 may deteriorate. Further, if the thickness of the gold-silver alloy plating layer 1d exceeds 0.5 μm, the amount of expensive precious metals used increases, and the cost increases, which is not preferable.

The gold content in the gold-silver alloy plating layer 1d is 80% by mass or more and 95% by mass or less. The gold content in the gold-silver alloy plating layer 1d is preferably 82% by mass or more and 95% by mass or less, more preferably 85% by mass or more and 95% by mass or less. If the gold content in the gold-silver alloy plating layer 1d is less than 80% by mass, the content of gold is small, so discoloration due to sulfidation is likely to occur. It becomes difficult to maintain the luminous flux. When the gold content in the gold-silver alloy plating layer 1d exceeds 95% by mass, the content of gold, which is inferior to silver in adhesion to the resin material, increases, so the adhesion to the resin material decreases, and the solder becomes an optical semiconductor. It is difficult to prevent the encapsulating material from entering the apparatus and from leaking to the outside, and it may not be possible to improve the adhesion with the resin material.

The gold-silver alloy plating layer 1d need not be provided on the entire surface of the metal material 1 for optical semiconductor devices. That is, at least a part of the surface of the metal material 1 for optical semiconductor devices should be the gold-silver alloy plating layer 1d. For example, among the lead frames 10 that are not exposed on the bottom surface of the concave portion of the resin molded body 3 shown in FIGS. In order to improve the adhesion with the resin, the embedded portion that is in close contact with the resin requires a gold-silver alloy plating layer 1d on its surface. The gold-silver alloy plating layer 1d may not be provided on the surface of the mounting portion exposed to the outside. In order to provide the gold-silver alloy plating layer 1d on a part of the metal material 1 for an optical semiconductor device in this way, when the gold-silver alloy plating layer 1d is formed, the part that does not require the gold-silver alloy plating layer 1d is covered with a protective tape. A gold-silver alloy plating layer 1d can be formed on a part of the surface by masking.

If the gold-silver alloy plating layer 1d is a portion that is not in direct contact with the resin molded body 3 or the sealing member 5, the plate-shaped metal material 1 for an optical semiconductor device is provided on two opposing surfaces as in the present embodiment. For example, it may be provided on both the top surface and the bottom surface, or it may be provided only on one surface and not provided on the other surface. Alternatively, it may be provided only partially in one plane. In addition, the gold-silver alloy plating layer 1d may have the same thickness over the entire area provided, or may have different thicknesses. Cost can be reduced more effectively by making the thicknesses different. For example, the gold-silver alloy plating layer 1d may be provided on the upper surface and the bottom surface of the metal material 1 for optical semiconductor devices, and the thickness of one surface may be thicker than the other. By providing the relatively thick gold-silver alloy plating layer 1d in the portion directly in contact with the resin molding 3 or the sealing member 5, for example, when the optical semiconductor device 100 is solder reflow-mounted on a printed circuit board, the solder becomes an optical semiconductor. Entry into the device 100 can be more effectively suppressed.

Substrate 1a
A metal material 1 for an optical semiconductor device has a substrate 1a on which a gold-silver alloy plating 1d is laminated on the surface layer. In this embodiment, the substrate 1a is used as a material that determines the rough shape of the metal material 1 for an optical semiconductor device.

As the material of the substrate 1a, copper, iron, alloys thereof, or a clad material (for example, copper/iron-nickel alloy/copper lamination) can be suitably used. Copper and its alloys are preferably used because of their excellent heat dissipation properties. In particular, plate-shaped copper and copper alloys are preferable because they are excellent in terms of mechanical properties, electrical properties, workability, and the like. Since the clad material can keep the coefficient of linear expansion low, the reliability of the optical semiconductor device 100 can be improved.

The thickness and shape of the substrate 1a can be selected variously according to the shape of the optical semiconductor device 100 and the like. For example, the shape can be plate-like, block-like, film-like, or the like. Furthermore, it may be a wiring pattern formed by printing on a ceramic or the like, or a formed wiring pattern plated with copper or an alloy thereof.

In order to increase the light reflectance of the metal material 1 for an optical semiconductor device, the flatness of the substrate 1a is preferably as high as possible. For example, it is preferable that the surface roughness Ra of the substrate 1a is 0.5 μm or less. As a result, the flatness of the nickel or nickel alloy layer 1b provided on the substrate 1a, the rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c and the gold-silver alloy plating layer 1d, which are provided as necessary, can be improved. can. Further, when the flatness of the substrate 1a is high, the flatness of the gold-silver alloy plated layer 1d having a thickness of 0.01 μm or more and 0.5 μm or less can be made high, and the reflectance of the metal material 1 for an optical semiconductor device can be improved. can be increased to The flatness of the substrate 1a can be improved by performing processing such as rolling, physical polishing, and chemical polishing. The flatness of the substrate 1a can also be enhanced by plating with the same material as the material forming the substrate 1a. For example, in the case of the substrate 1a made of a copper alloy, the flatness of the substrate 1a can be improved by performing copper alloy plating.

Nickel or nickel alloy layer 1b
A metal material 1 for an optical semiconductor device of this embodiment has a nickel or nickel alloy plating layer 1b on a substrate 1a.

The thickness of the nickel or nickel alloy plating layer 1b is preferably 0.5 μm or more and 10 μm or less, more preferably 1 μm or more and 10 μm or less. When the thickness of the nickel or nickel alloy plating layer 1b is 0.5 μm or more, the metal contained in the substrate 1a from the substrate 1a is the underlying layer of rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c and the surface layer. Diffusion into the gold or gold alloy plating layer 1d can be effectively reduced. When the nickel or nickel alloy plating layer 1b has a thickness of 10 μm or less, raw materials and manufacturing costs can be reduced. As a material for the nickel or nickel alloy plating layer 1b, for example, in addition to nickel, alloys such as nickel phosphorus, nickel tin, and nickel cobalt can be used.

Embodiment 3
2. Metallic Material for Optical Semiconductor Device FIG. 2B is a schematic cross-sectional view showing another embodiment of the metallic material 1 for an optical semiconductor device that constitutes the lead frame 10 . The metal material 1 for an optical semiconductor device preferably has a rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c as a base layer 1c between the nickel or nickel alloy plating layer 1b and the gold/silver alloy plating layer 1d. .

Rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c
The metal material 1 for an optical semiconductor device of this embodiment preferably has a rhodium, palladium, rhodium alloy, or palladium alloy plating layer 1c as a base layer in contact with the nickel or nickel alloy plating layer 1b. When the substrate 1a made of a material containing copper is used, a nickel or nickel alloy plating layer 1b is provided on the substrate 1a, and a rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c is formed thereon as a second underlayer. It is preferable that a gold-silver alloy plated layer 1d is laminated in this order as a surface layer. With such a configuration, for example, when copper is contained in the substrate 1a, the copper contained in the substrate 1a can be suppressed from diffusing into the gold-silver alloy plating layer 1d. Adhesion can be improved. Moreover, by suppressing the diffusion of copper contained in the substrate 1a, when the metal material 1 for an optical semiconductor device is used as the lead frame 10, the wire bondability can be improved.

The thickness of the rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c is preferably 0.01 μm or more and 0.3 μm or less, more preferably 0.02 μm or more and 0.2 μm or less, still more preferably 0.03 μm or more and 0.03 μm or more. .1 μm or less. If the thickness of the rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c is 0.01 μm or more and 0.3 μm or less, the metal contained in the substrate 1a is suppressed from diffusing into other underlying layers and surface layers, Adhesion can be improved.

The underlying layer 1c of the gold-silver alloy plating layer 1d may be a layer that serves both to prevent sulfurization and to prevent diffusion of the metal contained in the substrate 1a to other layers. Thereby, cost can be reduced. For example, gold is preferably used because it does not readily react with sulfur components and is highly effective in preventing the diffusion of metals contained in the substrate 1a.

It is preferable that the metal material 1 for an optical semiconductor device has a substantially flat plate shape, for example, as shown in FIGS. 3A and 3B described later. Thereby, the reliability of the metal material 1 for optical semiconductor devices can be improved. The nickel or nickel alloy plated layer 1b is somewhat more brittle than copper, iron, alloys thereof, or clad material (e.g. copper/iron-nickel alloy/copper lamination) used as the substrate 1, so the nickel or nickel alloy plated layer It is preferable to use the metal material 1 for an optical semiconductor device having 1b as it is in the form of a flat plate without being bent.

Embodiment 4
Optical Semiconductor Device FIGS. 3A and 3B show the structure of an optical semiconductor device 200 according to the fourth embodiment. An optical semiconductor device 200 of this embodiment has a lead frame 10 that does not have a bent portion. The same reference numerals are assigned to members that are common to the optical semiconductor device 100 of the first embodiment.
Next, each member constituting the optical semiconductor device 100 of Embodiment 1 and the optical semiconductor device 200 of Embodiment 4 will be described.

Light emitting element 2
As the light emitting element 2, a semiconductor light emitting element with an arbitrary wavelength can be selected. For example, as the blue and green light emitting elements 2, nitride semiconductors such as InGaN, GaN, AlGaN, and GaP can be used. GaAlAs, AlInGaP, or the like can be used as a red light emitting element. Furthermore, light-emitting elements 2 made of other materials can also be used. The composition, emission color, size and number of the light emitting elements 2 to be used can be appropriately selected according to the purpose.

When the optical semiconductor device includes a wavelength-convertable member, a nitride semiconductor capable of emitting short-wavelength light that can efficiently excite the wavelength-convertable member is suitable. Various emission wavelengths can be selected depending on the material of the semiconductor layer and its mixed crystal ratio. Further, the light emitting element 2 can be configured to output not only light in the visible light region but also ultraviolet rays and infrared rays.

The light emitting element 2 is preferably mounted on a lead frame 10 or substrate made of the metal material 1 for optical semiconductor devices. Thereby, the light extraction efficiency of the optical semiconductor device can be improved.

The light emitting element 2 has positive and negative electrodes electrically connected to the conductive member. These positive and negative electrodes may be provided on one surface side, or may be provided on both upper and lower surfaces of the light emitting element 2 . The connection with the conductive member may be made by a joint member 4 and a wire 6, which will be described later, or by flip-chip mounting.

Resin molding 3
The resin molding 3 is a member made of a resin composition that integrally holds the pair of lead frames 10 . The shape of the resin molded body 3 in plan view may be a substantially rectangular shape in which a pair of opposing sides are longer than the other opposing sides as shown in FIG. 1A, or a square shape as shown in FIG. It can be. In addition, the resin molded body 3 may have a polygonal shape, or a shape that is a combination thereof. When the resin molding 3 has a recess, the side wall 31 of the recess may have an inclined surface provided at an angle with respect to the bottom surface as shown in FIG. and may have a stepped surface. Also, the height and the shape of the opening can be appropriately selected according to the purpose and application. A lead frame 10 is preferably provided inside the recess. The space between the pair of lead frames 10 is filled with the resin composition forming the resin molded body 3 to form a part 32 of the bottom surface of the resin molded body 3 .

The resin molding 3 can be formed using a resin composition containing a thermosetting resin or a thermoplastic resin. In particular, it is preferable to use a resin composition containing a thermosetting resin. As the composition containing a thermosetting resin, a resin having a lower gas permeability than the resin used for the sealing member 5 is preferable. Specifically, an epoxy resin composition, a silicone resin composition, and a silicone-modified epoxy resin. modified epoxy resin compositions, modified silicone resin compositions such as epoxy modified silicone resins, polyimide resin compositions, modified polyimide resin compositions, urethane resins, modified urethane resin compositions, and the like. The resin composition constituting the resin molding 3 contains TiO ₂ , SiO ₂ , Al ₂ O ₃ , MgO, MgCO ₃ , CaCO ₃ , Mg(OH) ₂ and Ca(OH) ₂ as fillers. It may contain at least one inorganic particle selected from. The light transmittance of the resin molded body 3 can be adjusted by including inorganic particles as a filler in the resin composition constituting the resin molded body 3 .

Besides the resin molding 3, the member for holding the lead frame 10 may be made of an inorganic material such as ceramic, glass, or metal. As a result, an optical semiconductor device with little deterioration and high reliability can be obtained.

Joining member 4
The joining member 4 is a member for fixing and mounting the light emitting element 2 on the lead frame 10 . Materials for the conductive joining member 4 include conductive paste containing silver, gold, and palladium, eutectic solder materials such as gold-tin and tin-silver-copper, brazing materials such as low melting point metals, copper, silver, and gold. Materials similar to particles, silver or silver alloy plating layers can be used. As the insulating joining member 4, an epoxy resin composition, a silicone resin composition, a polyimide resin composition, a modified resin thereof, a hybrid resin, or the like can be used. When using these resins, a metal layer with high reflectance such as an aluminum film or a silver film or a dielectric reflective film is provided on the mounting surface of the light emitting element 2 in consideration of deterioration due to light or heat from the light emitting element 2. be able to.

sealing member 5
The sealing member 5 is provided so as to cover the light emitting element 2, the lead frame 10, the wire 6, and a protective film to be described later. By providing the sealing member 5, the optical semiconductor device can protect the coated member from dust, moisture, external force, and the like, and the reliability of the optical semiconductor device can be improved. In particular, by providing the sealing member 5 on the protective film after forming the protective film, the protective film can be protected, so that the reliability of the optical semiconductor device is enhanced.

The sealing member 5 preferably has translucency that allows the light from the light emitting element 2 to pass therethrough, and also has light resistance that is less likely to be deteriorated by them. Specific materials used for the sealing member 5 include a silicone resin composition, a modified silicone resin composition, a modified epoxy resin composition, a fluororesin composition, and the like, which have translucency that allows the light from the light emitting element to pass therethrough. An insulating resin composition can be mentioned. In particular, hybrid resins containing at least one resin having a siloxane skeleton as a base, such as dimethyl silicone, phenyl silicone with a low phenyl content, and fluorine-based silicone resins, can also be used.

As a method for forming the sealing member 5, when resin is contained in the material constituting the sealing member 5, a potting (dropping) method, a compression molding method, a printing method, a transfer molding method, a jet dispensing method, a spray coating method, or the like is used. be able to. A potting method is preferable when the optical semiconductor device has a resin molded body 3 having a concave portion, and a compression molding method or a transfer molding method is preferable when the optical semiconductor device uses a flat substrate.

As shown in FIG. 1B or 3B, the sealing member 5 is preferably provided so as to fill the recess of the resin molding 3 .

The shape of the outer surface of the sealing member 5 can be selected variously according to the light distribution characteristics required for the optical semiconductor device. For example, by forming the upper surface into a convex lens shape, a concave lens shape, a Fresnel lens shape, a rough surface, or the like, it is possible to adjust the directivity and light extraction efficiency of the optical semiconductor device.

The sealing member 5 can also contain a coloring agent, a light diffusing agent, a light reflecting material, various fillers, a wavelength conversion member, and the like.

The wavelength conversion member is a material that converts the wavelength of light from the light emitting element 2 . When the light emitted from the light emitting element 2 is blue light, an yttrium-aluminum-garnet phosphor (hereinafter referred to as "YAG:Ce"), which is a type of aluminum oxide phosphor, is suitable as the wavelength conversion member. used for Since the YAG:Ce phosphor absorbs part of the blue light from the light emitting element and emits complementary yellow light, it is relatively easy to manufacture a high-output optical semiconductor device that emits mixed white light. can be formed into

wire 6
A wire 6 connects the light emitting element 2 and a conductive member such as a lead frame 10 . Materials for the wires 6 are preferably gold, aluminum, copper, and alloys thereof. The wire 6 may have a core with a coating layer made of a material other than the core, for example, a copper core with a coating layer of palladium or a palladium-gold alloy on the surface. Among others, the material of the wire 6 is preferably selected from any one of highly reliable gold, silver, and silver alloys. In particular, silver or a silver alloy with high light reflectance is preferable. Especially in this case, the wire 6 is preferably covered with a protective film. As a result, sulfuration and disconnection of the wire containing silver can be prevented, and the reliability of the optical semiconductor device can be improved. Further, when the substrate 1a of the optical semiconductor device metal material constituting the lead frame 10 is made of copper, and the wire 6 is made of silver or a silver alloy, the optical semiconductor device metal material 1 includes the nickel or nickel alloy plating layer 1b. By providing, the formation of local cells between copper and silver can be suppressed. As a result, deterioration of the lead frame 10 and the wires 6 is suppressed, and a highly reliable optical semiconductor device can be obtained.

Protective Film The optical semiconductor device may further include a protective film. The protective film covers at least the gold-silver alloy plating layer 1 d provided on the surface of the optical semiconductor device metal material 1 constituting the lead frame 10 . The protective film is a member that suppresses discoloration or corrosion of the gold-silver alloy plated layer 1d on the surface of the optical semiconductor device metal material 1 that mainly constitutes the lead frame 10 . Furthermore, optionally, the surface of members other than the lead frame 10 such as the light emitting element 2, the bonding member 4, the wire 6, the base body (resin molded body 3), or the metal for an optical semiconductor device on which the gold-silver alloy plating layer 1d is not provided The surface of material 1 may be coated. A protective film is preferably provided to cover the wire 6 when the wire 6 is silver or a silver alloy. As a result, sulfuration and disconnection of the wire containing silver can be prevented, and the reliability of the optical semiconductor device can be improved.
The protective film is preferably formed by an atomic layer deposition method (hereinafter also referred to as ALD (Atomic Layer Deposition)). According to the ALD method, a very uniform protective film can be formed, and the formed protective film is denser than protective films obtained by other film forming methods. can very effectively prevent sulfidation of the indium or indium alloy plating layer 1d of the metal material 1 for an optical semiconductor device.

Materials for the protective film include _{Al2O3 , SiO2} , _TiO2 , _ZrO2 , ZnO, _{Nb2O5 , MgO} , _In2O3 , _Ta2O5 , _HfO2 , _SeO , _{Y2O3 ,} Examples include oxides such as SnO ₂ , nitrides such as AlN, TiN and ZrN, and fluorides such as ZnF ₂ and SrF ₂ . These may be used alone or in combination. Alternatively, they may be laminated.

Due to the difference in coefficient of thermal expansion between the joining member 4 and the lead frame 10, cracks are formed in the protective film around the light emitting element 2, and the metal material 1 for an optical semiconductor device constituting the lead frame 10 near the light emitting element 2. , the gold-silver alloy plating layer 1d may be oxidized. Oxidation proceeds by setting the thickness of the gold-silver alloy plating layer 1d of the optical semiconductor device metal material 1 constituting the lead frame 10 to 0.01 μm or more and 0.5 μm or less and the gold content of 80% by mass or more and 95% by mass or less. is reduced, and a decrease in the reflectance of the lead frame 10 can be suppressed.

The optical semiconductor device can include various members in addition to those described above. For example, a Zener diode can be mounted as a protective element.

Method for Manufacturing Optical Semiconductor Device Next, as an example of a method for manufacturing an optical semiconductor device, a method for manufacturing the optical semiconductor device 200 of Embodiment 4 will be described with reference to FIGS. 4A to 4D.
As shown in FIG. 4A, a lead frame 10 made of the metal material 1 for an optical semiconductor device according to Embodiment 2 or 3 of the present invention is prepared. Specifically, a metal plate of, for example, copper that constitutes the substrate 1a of the metal material 1 for optical semiconductor devices is punched, and then plated with nickel or a nickel alloy as described later in the manufacturing method of the metal material 1 for optical semiconductor devices. A layer 1b, a rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c if necessary, and a gold-silver alloy plating layer 1d are formed to form a lead frame 10. FIG.

As shown in FIG. 4B, the resin molding 3 is formed on the lead frame 10 by the transfer molding method. The resin molded body 3 is formed such that a pair of lead frames 10 serving as leads are exposed from the bottom surface of the concave portion of the resin molded body 3 . That is, the lead frame 10 is exposed on the bottom surface of the concave portion of each resin molded body 3 .

Next, as shown in FIG. 4C, the light-emitting element 2 is mounted via a bonding member (not shown) in the region of the lead frame 10 on which the resin molding 3 is formed, in which the light-emitting element 2 is to be mounted. Then, the light emitting element 2 and the lead frame 10 are connected by a wire (not shown). After that, a sealing member 5 is provided in each concave portion of the resin molded body 3 .

Then, the lead frame 10 and the resin molded body 3 as shown in FIG. 4D are cut by using a dicing saw or the like to individualize individual optical semiconductor devices as shown in FIGS. 3A and 3B. This cutting exposes the cross section of the lead frame 10 to the outer surface of the optical semiconductor device 200 . In this cross section, the copper base 1a of the optical semiconductor device metal material 1 constituting the lead frame 10; Furthermore, the gold-silver alloy plating layer 1d is exposed.

Embodiment 5
Method for Producing Metal Material for Optical Semiconductor Devices Next, a method for producing a metal material for optical semiconductor devices will be described.
A method for manufacturing a metal material for an optical semiconductor device according to Embodiment 5 includes the steps of forming a nickel or nickel alloy plating layer on a substrate, and forming a rhodium, palladium, rhodium alloy, or palladium alloy plating layer as necessary. and forming a gold-silver alloy plating layer having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80 mass % or more and 95 mass % or less.

The substrate may be wet-etched to form a step at a predetermined position, and after forming the step, each of the above steps may be performed.

The steps of forming a layer of nickel or nickel alloy plating, optionally forming a layer of rhodium, palladium, rhodium alloy or palladium alloy plating, and forming a layer of gold-silver alloy plating are performed separately. Electroplating or electroless plating is preferable because the plating layer can be easily formed. Among them, the electroplating method is preferable because the rate of layer formation is high and the productivity can be improved.

Prior to plating, the substrate may be pretreated. The pretreatment includes acid treatment with dilute sulfuric acid, dilute nitric acid, dilute hydrochloric acid, etc., and alkali treatment with sodium hydroxide, etc. These pretreatments may be performed once or several times in the same treatment or in combination with different treatments. When the pretreatment is performed several times, it is preferable to wash with running pure water after each treatment. When the substrate is a metal plate made of copper or an alloy containing copper, it is preferable to use dilute sulfuric acid for the pretreatment. When the substrate is a metal plate made of iron or an alloy containing iron, it is preferable to use dilute hydrochloric acid for the pretreatment.

The metal material for an optical semiconductor device preferably further includes a step of heat-treating at a temperature of 200° C. or higher and 450° C. or lower for a treatment time of 5 minutes or more and 2 hours or less after forming each layer. The heat treatment may be performed in the air, in an inert atmosphere such as nitrogen gas, or in a reducing atmosphere such as hydrogen gas, but the heat treatment is preferably performed in a nitrogen gas atmosphere in order to prevent oxidation of silver during gold-silver alloy plating. As the heat treatment method, batch treatment such as in a hot air thermostat may be used, or continuous heat treatment may be performed by providing a hot air furnace or an infrared furnace in the final step of a continuous plating apparatus. These heat treatments are preferable because the metals of the substrate 1a and each plated layer appropriately interdiffuse, and the adhesion between the substrate 1a and the nickel or nickel alloy plated layer 1b and between the plated layers 1b, 1c and 1d is improved. Note that the temperature and treatment time of the heat treatment can be determined in consideration of the combination of the thicknesses of the respective plating layers.

In the step of forming a nickel or nickel alloy plating layer, if the material constituting the plating layer is pure nickel, it can be formed by electroplating using a plating solution containing nickel sulfamate, for example. In the case of a nickel-phosphorus alloy, it can be formed by electroless plating using a nickel hypophosphite plating solution.

In the step of forming a rhodium, palladium, rhodium alloy, or palladium alloy plating layer, if the material forming the plating layer is palladium or a palladium alloy, electroplating is performed using a plating solution containing, for example, tetraamminepalladium chloride. can be formed by When the material forming the plated layer is rhodium or a rhodium alloy, it can be formed by electroplating using a plating solution containing rhodium sulfate, for example.

In the step of forming the gold-silver alloy plating layer, potassium gold cyanide or gold cyanide is contained at a metal gold concentration of 0.5 g / L or more and 10 g / L or less, and silver cyanide potassium or silver cyanide is contained at a metal silver concentration of 0 .05 g/L or more and 2 g/L or less, the mass concentration ratio of metallic gold and metallic silver (gold/silver) is 95/5 to 80/20, and cyanide salt is 0.5 g/L or more and 150 g/L or less It is preferable to use a plating solution containing By using a plating solution having a bath composition in which the concentration ratio of potassium gold cyanide or gold cyanide and potassium silver cyanide or silver cyanide is from 95/5 to 80/20, the thickness can be reduced from 0.01 μm to 0.01 μm. A gold-silver alloy plated layer 1d having a thickness of 5 μm or less and a gold content of 80% by mass or more and 95% by mass or less can be formed. Examples of cyanide salts include potassium cyanide and sodium cyanide.

It is preferable that the plating solution contains 5 g/L or more and 150 g/L or less of at least one electrically conductive salt selected from the group consisting of cyanates, carbonates, phosphates, nitrates, citrates and sulfates. If the electroconductive salt contained in the plating solution is 5 g/L or more and 150 g/L or less, the ion mobility can be increased without excessively increasing the electrical resistance of the plating solution and without excessively increasing the viscosity of the plating solution. The plating solution can be used industrially stably without deterioration. In addition, if the electroconductive salt contained in the plating solution is 5 g/L or more and 150 g/L or less, the viscosity of the plating solution does not become excessive, and the so-called plating solution is less likely to be carried out by the object to be plated. gold and silver alloy plating can be applied. Cyanide includes potassium cyanide and sodium cyanide. Carbonates include potassium carbonate, sodium carbonate, ammonium carbonate and the like. Phosphates include potassium phosphate, sodium phosphate, ammonium phosphate, potassium pyrophosphate and the like. Nitrates include potassium nitrate, sodium nitrate, ammonium nitrate and the like. Citrate salts include potassium citrate, sodium citrate, ammonium citrate and the like. Sulfate salts include potassium sulfate, sodium sulfate, and the like.

In the step of forming a gold-silver alloy plating layer, a plating solution is used, the temperature of the plating solution is 20° C. or higher and 70° C. or lower, and the anode is a soluble electrode made of gold or a gold-silver alloy, or stainless steel, platinum, or platinum-coated titanium. Electroplating is preferably carried out using electrodes, with a cathodic current density of 0.1 A/dm ² or more and 2 A/dm ² or less on the conductive substrate and a plating time of 5 seconds or more and 10 minutes or less. Under these conditions, a gold-silver alloy plating layer having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80% by mass or more and 95% by mass or less can be industrially stably and economically formed. can be done.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples. The invention is not limited to these examples.

Example 1
As shown in FIG. 2A, each plating solution having the bath composition shown below was prepared with the following substrate 1a on the surface, a nickel or nickel alloy plating layer 1b, and a gold-silver alloy plating layer 1d as a surface layer thereon in this order. was used to form a metal material 1 for an optical semiconductor device by electroplating under each condition. Using this metal material 1 for an optical semiconductor device, a lead frame 10 as a pair of lead frames was prepared. The thickness of each layer in the examples is shown in Table 1. The plating time was adjusted from 5 seconds to 10 minutes.

Substrate 1a of Example 1
Copper substrate: TAMAC194 material manufactured by Mitsubishi Shindoh Co., Ltd. was pressed into a lead frame shape using a press die.

Nickel or nickel alloy plating layer 1b of Example 1
For the nickel plating layer 1b, a plating solution having the following bath composition was used as a standard sulfamic acid electroplating bath.
Nickel or nickel alloy plating solution Nickel sulfamate sulfate: 450g/L
Nickel chloride: 10g/L
Boric acid: 30g/L
pH 4.0
A nickel plating layer was formed by electroplating using the above plating solution at a solution temperature of 55° C. and a cathode current density of 5 A/dm ² after adjusting the plating time. A sulfur-added nickel plate was used as the anode.

Gold-silver alloy plating layer 1d of Example 1
Gold and silver alloy plating solution 1
Potassium gold cyanide: 9 g/L as gold
Potassium silver cyanide: 1 g / L as silver (gold 90% by mass, silver 10% by mass)
Potassium cyanide: 120g/L
Potassium carbonate: 15g/L
A gold-silver alloy plated layer was formed by electroplating using the above-mentioned plating solution at a solution temperature of 30° C. and a cathode current density of 0.8 A/dm ² while adjusting the plating time. A soluble gold-silver alloy electrode with a gold content of 90% by mass was used as the anode.

Example 2
As shown in FIG. 2B, the following substrate 1a is provided on the surface, a nickel or nickel alloy plating layer 1b, a rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c as a base layer thereon, and a gold and silver plating layer 1c as a surface layer thereon. The alloy plating layer 1d was formed into the metal material 1 for an optical semiconductor device in this order by electroplating under each condition using each plating solution having the bath composition shown below. Using this metal material 1 for an optical semiconductor device, a lead frame 10 as a pair of lead frames was prepared.

Nickel or nickel alloy plating layer 1b of Example 2
The same plating solution as in Example 1 was used for forming the substrate 1a and the nickel plating layer.

Palladium plating layer 1c of Example 2
For the palladium plating layer 1c of Example 2, a plating solution having the following bath composition was used.
Palladium or palladium alloy plating solution Tetraamminepalladium chloride: 5 g/L as palladium
Ammonium nitrate: 150g/L
Sodium 3-pyridinesulfonate: 5g/L
pH 8.5
A palladium plated layer was formed by electroplating using the above plating solution at a solution temperature of 50° C. and a cathode current density of 1 A/dm ² while adjusting the plating time. A platinum-coated titanium electrode was used as the anode.

Gold-silver alloy plating layer 1d of Example 2
For the gold-silver alloy plating layer 1d of Example 2, a plating solution having the following bath composition was used.
Gold and silver alloy plating solution 2
Potassium gold cyanide: 4.25 g/L as gold
Potassium silver cyanide: 0.75 g / L as silver (85% by weight of gold, 15% by weight of silver)
Potassium cyanide: 30g/L
Potassium citrate: 80g/L
Potassium phosphate: 50g/L
pH 9.5
A gold-silver alloy plated layer was formed by electroplating using the above plating solution at a solution temperature of 30° C. and a cathode current density of 1 A/dm ² after adjusting the plating time. A platinum-coated titanium electrode was used as the anode.

Example 3
As shown in FIG. 2B, the following substrate 1a is provided on the surface, a nickel or nickel alloy plating layer 1b, a rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c as a base layer thereon, and a gold and silver plating layer 1c as a surface layer thereon. The alloy plating layer 1d was formed into the metal material 1 for an optical semiconductor device in this order by electroplating under each condition using each plating solution having the bath composition shown below. Using this metal material 1 for an optical semiconductor device, a lead frame 10 as a pair of lead frames was prepared.

Nickel or nickel alloy plating 1a of Example 3
The same plating solution as in Example 1 was used for forming the substrate 1a and the nickel plating layer.

Rhodium plating layer 1c of Example 3
For the rhodium plating layer 1c of Example 3, a plating solution having the following bath composition was used.
Rhodium or rhodium alloy plating solution Rhodium sulfate: 2g/L as rhodium
Sulfuric acid: 50g/L
Lead sulfate: 10 mg/L as lead
Using the above plating solution, the plating time was adjusted, and electroplating was performed at a solution temperature of 45° C. and a cathode current density of 1 A/dm ² to form a rhodium plating layer. A platinum-coated titanium electrode was used as the anode.

Gold-silver alloy plating layer 1d of Example 3
For the gold-silver alloy plating layer 1d of Example 3, a plating solution having the following bath composition was used.
Gold and silver alloy plating solution 3
Potassium gold cyanide: 4.75 g/L as gold
Potassium silver cyanide: 0.25 g/L as silver (95% by weight of gold, 5% by weight of silver)
Potassium cyanide: 1 g/L
Potassium citrate: 120g/L
Potassium phosphate: 50g/L
pH 6.5 (adjusted with citric acid)
A gold-silver alloy plated layer was formed by electroplating using the above plating solution at a solution temperature of 45° C. and a cathode current density of 1 A/dm ² after adjusting the plating time. A platinum-coated titanium electrode was used as the anode.

Examples 4 to 11
A metal material 1 for an optical semiconductor device of each example was formed in the following manner. Using this metal material 1 for an optical semiconductor device, a lead frame 10 as a pair of lead frames was prepared.

Substrate 1a of Examples 4 to 11
As the substrate, the same copper substrate as in Example 1 or the substrate shown below was used.
Substrate of 42 alloy alloy: An iron-nickel alloy (Fe-42% Ni) of 42% Ni--Fe manufactured by Dowa Metanics Co., Ltd. was pressed into a lead frame shape using a press die. Iron material: SPCE-SB manufactured by Nippon Steel & Sumitomo Metal Corporation and formed into a lead frame shape with a press die was used.

Nickel or nickel alloy plating layer 1b of Examples 4 to 11
The plating solution for forming the nickel alloy plating layer is the same plating solution as in Example 1, or a plating solution obtained by adding an appropriate amount of tin sulfamate or cobalt sulfamate to the plating solution having the bath composition of Example 1. A nickel plating layer 1b, a nickel-tin alloy plating layer 1b, or a nickel-cobalt plating layer was formed.

Rhodium, palladium, rhodium alloy or palladium alloy plating layer 1c of Examples 4 to 11
When forming the palladium or palladium alloy plating layer 1c, a plating solution having the same bath composition as in Example 2 for forming a palladium plating layer, or a plating solution having the bath composition of Example 2 is added with an appropriate amount of nickel sulfate. Then, the plating time was adjusted, and the palladium plating layer 1c or the palladium nickel alloy plating layer 1 was formed under the same conditions as in Example 2.
In the case of forming the rhodium or rhodium alloy plating layer 1c, the plating solution having the same bath composition as in Example 3 for forming the rhodium plating layer, or the plating solution having the bath composition of Example 3 was added with an appropriate amount of cobalt sulfate. was added to adjust the plating time, and under the same conditions as in Example 3, a rhodium plated layer 1c or a rhodium-nickel alloy plated layer 1c was formed.

Gold-silver alloy plating layer 1d of Examples 4 to 11
The same plating solution as in Example 2 was used except that the concentration ratio of gold and silver was adjusted to each ratio shown in Table 1, the plating time was adjusted, and other conditions were the same as in Example 2. An alloy plating layer was formed.

Comparative Examples 1 to 3
As Comparative Example 1, a metal material having the same structure as that of Example 1 and having the gold/silver concentration ratio and the thickness of the gold/silver alloy plated layer 1d as shown in Table 1 was prepared. As Comparative Examples 2 and 3, metallic materials having the same structure as in Example 2 and having the gold/silver concentration ratio and the thickness of the gold/silver alloy plated layer 1d as shown in Table 1 were prepared. Using this metal material, a lead frame 10 as a pair of lead frames was prepared.

Reflectance and L ^* a ^* b ^* b ^* value in color system The metal materials for optical semiconductor devices of Examples and Comparative Examples were measured at 450 nm using a micro portion reflectance measuring device MCPD manufactured by Otsuka Electronics Co., Ltd. A light having an emission peak wavelength was irradiated and the reflectance was measured. Furthermore, using a color difference meter VSS-400 manufactured by Nippon Denshoku Industries Co., Ltd., the b ^* value in the L ^* a ^* b ^* color system was measured. The results are shown in Table 1.

Optical Semiconductor Device Next, optical semiconductor devices having substantially the same structure as the optical semiconductor devices shown in FIGS. 1A and 1B were manufactured using the metal materials for optical semiconductor devices of Examples and Comparative Examples as lead frames. Until the semiconductor device 100 is separated into individual pieces, each step is performed in the state of an assembly in which a plurality of resin moldings 3 are formed on a plurality of lead frames 1 in a state in which a plurality of paired lead frames 1 are connected. For convenience, one optical semiconductor device 100 (singular) shown in FIGS. 1A and 1B will be described. Using this lead frame 10, optical semiconductor devices of Examples and Comparative Examples having substantially the same structure as the optical semiconductor devices shown in FIGS. 1A and 1B were manufactured.

The resin molding 3 has a recess, and the metal material 1 for an optical semiconductor device is exposed on the bottom surface of the recess. A rectangular light-emitting element 2 having positive and negative electrodes on its upper surface was placed on the metal material 1 for an optical semiconductor device, and was bonded by using a translucent resin as a bonding member 4 . After that, a YAG phosphor and a sealing material containing a translucent resin were dripped into the concave portion by a potting method to form a sealing member 5 .

Presence or absence of solder intrusion into the resin molded body and sealing resin leakage After mounting at 260° C. for 10 seconds, the reflowed optical semiconductor device was peeled off, and a stereoscopic microscope was used to evaluate whether or not solder penetrated into the resin molded body 3 at a magnification of 40, and a sealing resin material (sealing resin). The presence or absence of leakage was also evaluated. The evaluation results are shown in Table 1.

Total luminous flux maintenance factor after anti-sulfurization test In order to evaluate anti-sulfur reliability, the optical semiconductor devices of each example and comparative example were tested under an environment of temperature of 40°C and humidity of 75% RH with 2 ppm of H ₂ S and 4 ppm of NO ₂ . The total luminous flux of light emitted from the optical semiconductor device was measured before and after the exposure treatment for 500 hours in the mixed gas containing the mixed gas, and the ratio obtained by dividing the total luminous flux after the exposure treatment by the total luminous flux before the exposure treatment was measured as the maintenance rate of the total luminous flux. did. The results are shown in Table 1.

In the optical semiconductor devices of Examples 1 to 11, no penetration of solder into the resin molded body 3 was observed, and leakage of sealing resin from the resin molded body 3 to the outside was not observed. Adhesion of the frame 10 was good. Moreover, the optical semiconductor devices of Examples 1 to 11 and Comparative Examples 1 to 3 maintained substantially the same total luminous flux after the sulfurization test as before the sulfurization test. In addition, the metal materials for optical semiconductor devices of Examples 1 to 11 have a reflectance of 25% or more and 45% or less for light having an emission peak wavelength of 450 nm, and a b ^* value in the L ^* a ^* b ^* color system. was 20 or more and 30 or less, had desired reflectance and chromaticity, and had good adhesion to the resin material constituting the member.

In the optical semiconductor devices of Comparative Examples 1 to 3, solder penetrated into the resin molded body 3 and the sealing resin leaked from the resin molded body 3 to the outside. was not improved. In Comparative Example 2, the gold content in the gold-silver alloy plating layer 1d was as low as 75% by mass, and the silver content was high. Therefore, discoloration due to sulfurization was not suppressed, and the total luminous flux maintenance factor after the sulfurization test decreased. did. In Comparative Example 3, since the gold-silver alloy plated layer 1d is as thin as 0.005 mm, the adhesiveness to the resin material is lowered, the solder penetrates into the resin molded body 3, and the sealing resin flows out from the resin molded body 3 to the outside. there was a leak.

DESCRIPTION OF SYMBOLS 100, 200 Optical semiconductor device 1 Metallic material for optical semiconductor device 1a Substrate 1b Nickel or nickel alloy plating layer 1c Base layer Rhodium, palladium, rhodium alloy or palladium alloy plating layer 1d Surface layer, gold and silver alloy plating layer 2 Light emitting element 3 Resin molding 31 side wall portion 32 bottom portion 4 joining member 5 sealing member 6 wire 10 lead frame

Claims (14)

on a conductive substrate,
a layer of nickel or nickel alloy plating;
A metal material for an optical semiconductor device, having a gold-silver alloy plating layer having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80% by mass or more and 95% by mass or less in this order. 2. The metal material for an optical semiconductor device according to claim 1, comprising a rhodium, palladium, rhodium alloy or palladium alloy plating layer between said nickel or nickel alloy plating layer and said gold-silver alloy plating layer. 3. The metal material for an optical semiconductor device according to claim 1, wherein the nickel or nickel alloy plating layer has a thickness of 0.5 [mu]m or more and 10 [mu]m or less. The metal material for an optical semiconductor device according to claim 2 or claim 3 , wherein the rhodium, palladium, rhodium alloy, or palladium alloy plating layer has a thickness of 0.01 μm or more and 0.3 μm or less. . 5. The metal material for an optical semiconductor device according to claim 1, which has a reflectance of 25% or more and 45% or less for light having an emission peak wavelength of 450 nm. 6. The metal material for an optical semiconductor device according to claim 1, wherein the b ^* value in the L ^* a ^* b ^* color system is 20 or more and 30 or less. An optical semiconductor device comprising a lead frame or a substrate made of the metal material for an optical semiconductor device according to any one of claims 1 to 6 and a light emitting element mounted thereon. 8. The optical semiconductor device according to claim 7, wherein a part of the surface of the lead frame or substrate made of said metal material for optical semiconductor devices has a portion that contacts a member formed using a resin material. on a conductive substrate,
forming a layer of nickel or nickel alloy plating;
optionally forming a layer of rhodium, palladium, rhodium alloy or palladium alloy plating;
forming a gold-silver alloy plating layer having a thickness of 0.01 μm or more and 0.5 μm or less and a gold content of 80% by mass or more and 95% by mass or less, in this order. Production method. 10. The method for producing a metal material for an optical semiconductor device according to claim 9, further comprising the step of heat-treating at a temperature of 200[deg.] C. or higher and 450[deg.] C. or lower for a treatment time of 5 minutes or more and 2 hours or less. 11. The method of manufacturing a metal material for an optical semiconductor device according to claim 9, wherein the step of forming said layer is performed by an electrolytic plating method or an electroless plating method. In the step of forming the gold-silver alloy plating layer,
Potassium gold cyanide or gold cyanide at a metal gold concentration of 0.5 g/L or more and 10 g/L or less, containing potassium silver cyanide or silver cyanide at a metal silver concentration of 0.05 g/L or more and 2 g/L or less, From claim 9, using a plating solution having a mass concentration ratio of metallic gold and metallic silver (gold/silver) of 95/5 to 80/20 and containing 0.5 g/L or more and 150 g/L or less of cyanide salt 12. The method for producing a metal material for an optical semiconductor device according to any one of 11. 12. The plating solution contains 5 g/L or more and 150 g/L or less of at least one electrically conductive salt selected from the group consisting of cyanates, carbonates, phosphates, nitrates, citrates and sulfates. A method for producing the metal material for an optical semiconductor device according to 1. In the step of forming the gold-silver alloy plating layer, the plating solution is used so that the temperature of the plating solution is 20° C. or higher and 70° C. or lower, and the anode is a soluble electrode made of gold or a gold-silver alloy, or stainless steel or platinum, Using a platinum-coated titanium electrode, electroplating is performed under the conditions that the cathode current density of the conductive substrate is 0.1 A / dm ² or more and 2 A / dm ² or less, and the plating time is 5 seconds or more and 10 minutes or less. 14. The method for manufacturing the metal material for an optical semiconductor device according to claim 13.

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