TW201030191A - Optical semiconductor device lead frame and manufacturing method thereof - Google Patents

Abstract

Disclosed is a lead frame for use in optical semiconductor devices which has excellent reflection characteristics with respect to visible light and excellent corrosion resistance, and wherein a pure silver layer composed of pure silver is formed on a substrate. The arithmetic mean height Ra of said pure silver layer is 0.001-0.2 μm, and on the surface thereof is formed a film with an average thickness of 0.001-0.2 μm composed of a metal material having excellent corrosion resistance.

Description

i 201030191 VI. Description of the Invention: [Technical Field] The present invention relates to a lead frame for two types of optical semiconductor devices and a method of manufacturing the same. [Prior Art] A lead frame for an optical semiconductor device has been widely used as a light source for various display and illumination for use in a light source. In the optical semiconductor device, for example, a lead frame is disposed on the substrate, and after the light-emitting element is mounted on the lead frame, the sealing resin is used to prevent deterioration of the light source caused by heat, moisture, oxidation, or the like, or deterioration of the peripheral portion thereof. The above light source and its surroundings are sealed. Further, a layer of silver or a silver alloy having excellent light reflection characteristics is formed in the direct vicinity of the light source. For example, Patent Document 1 or the like discloses that a mineral silver layer is formed in the vicinity of a reflector, and is disclosed in Patent Document 2 or the like. There is a method in which the crystal grain size of the silver or silver alloy film is set to 〇5 to 30 to improve the reflection characteristics and the like. Further, Patent Document 2 discloses a method of producing a silver film having the above crystal grain size by subjecting it to a silver film and then heat-treating at 200 degrees or more for 30 seconds or more. On the other hand, as a method of improving the corrosion resistance, for example, as disclosed in Patent Document 3, a method of forming palladium of 0.005 to 15 μm on the nickel base layer and forming 〇〇〇3 to 〇〇5 on the outermost layer is disclosed. rhodium. However, as in the case of the technique disclosed in the patent document, when the film of silver or its alloy film is simply formed, the wavelength of the ultraviolet region is particularly dripped, and reflection near the vicinity of the visible light region to around 300 nm cannot be avoided. 201030191 rate dropped. Further, if the crystal grain size is formed to be 0.5 // m or more as in the technique disclosed in Patent Document 2, although the reflectance in the visible light region does have a slight improvement, the wavelength of 400 nm or less is seen and patented. The phenomenon of the same technique disclosed in Document 1 cannot avoid the decrease in reflectance in the ultraviolet region. Further, when the crystal grain size is adjusted by the heat treatment, it is estimated that oxidation of silver due to the influence of residual oxygen causes a decrease in reflectance, and a sufficient effect cannot be obtained in terms of improvement in reflectance. Further, Patent Document 2 discloses that the surface roughness of the base material of the surface silver film has a maximum height Ry of 〇5 or more, but the reflection phenomenon of the light is not the thickness of the base portion and the thickness near the outermost layer. Degree will have an impact. Therefore, a silver film is formed on the substrate or the substrate plating to form a reflective layer by electroplating or vapor deposition, etc., so that it is meaningless even if the roughness of the substrate is defined. χ ' Ry is the difference between the maximum and minimum values of the coarse wheel. This is a good value for a specific part of the surface, for example, the value of a minute part such as a line-shaped scratch, and does not mean that it depends on the reflection. The thickness of the overall range 'and thus Ry is sometimes not suitable as a parameter indicating the characteristics of the reflective layer. Further, in the lead frame manufactured according to the technique disclosed in the above documents, when used in an LED, a decrease in luminance occurs over time. Investigation: , , ° ° It is known that the sealed resin contains a trace amount of sulfur, which causes the silver on one surface to vulcanize, so the silver turns black and the brightness decreases. Also, sterling silver is prone to migration. Further, in the lead frame disclosed in Patent Document 3, compared with silver, 姥201030191t is an important reflection characteristic for an optical semiconductor device, and particularly important, a reflectance including a wavelength of ~800 nm including a visible light region. When the thickness is reduced by 2% or more, the blue or white-based optical semiconductor device cannot satisfy the required characteristic of the reflectance if it is simply covered with a thinner germanium. Patent Document 1 曰 专利 丨 丨 883 883 883 883 883 883 883 883 883 883 883 883 883 883 883 883 883 883 883 883 883 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 674 SUMMARY OF THE INVENTION The present invention provides a lead frame having a good reflection characteristic in a range of 800 nm from a fan to a near-infrared region of an ultraviolet region, and further has heat dissipation and corrosion resistance (especially for light vulcanization) (4)) A lead frame excellent in long-term stability of reflectance and a method of manufacturing the same. In view of the above-mentioned problems, it has been found that the reflectance of light in the wavelength range from the ultraviolet region to the near-infrared region is more or less affected by the underlying metal if it is a metal layer having a thickness of 〇2" below the claw. It can be seen that, in order to improve the corrosion resistance in advance, if the arithmetic mean height Ra of the surface of the pure silver layer forming the reflective layer is controlled within the range of 丨七丨, the above-mentioned resistant film can be formed without causing the sterling silver layer to be exposed. . The result of the above-mentioned results is that a lead frame for an optical semiconductor device is formed by forming a pure silver layer made of pure silver on a substrate, and the arithmetic mean height of the pure silver layer is "1 to 0.2 _, and On the surface of the surface, please select (4) the metal with excellent resistance to money, which can provide the effect of maintaining the high reflectivity of the pure silver layer, and the excellent resistance to vulcanization and rot. 5 201030191 A lead frame for optical semiconductors having excellent long-term stability of the incident rate. That is, the present invention provides: (1) A lead frame for an optical semiconductor device, which is formed by forming a pure silver layer made of pure silver on a substrate, and is characterized by In the pure silver layer, the arithmetic mean height Ra is 0.001 to 0.2 〃m, and an average film thickness 〇〇〇1 composed of a metal material excellent in corrosion resistance against sulphide corrosion is formed on the surface thereof to be more than a claw, 0_2 // (2) The lead frame for an optical semiconductor device according to Item (1), wherein the base system is composed of a metal or an alloy selected from the group consisting of copper, copper alloy, aluminum, and aluminum alloy; 3) As in item (1) The lead frame for an optical semiconductor device according to Item (2), wherein at least the i layer is formed between the substrate and the pure silver layer, and is composed of a group selected from the group consisting of nickel nickel, cobalt, cobalt alloy, copper, and copper alloy. (4) The lead frame for an optical semiconductor device according to any one of the items (1) to (3), wherein the thickness of the sterling silver layer is 〇2 to 5 〇" (5) The lead frame for an optical semiconductor device according to any one of the items (1) to (4), wherein the metal material forming the film is selected from the group consisting of gold, gold alloy, silver, gold platinum, platinum A lead frame for an optical semiconductor device according to any one of the above items (1) to (5), wherein the above-mentioned metal or alloy is used in the group of the present invention. The metal material of the film is selected from the group consisting of silver-copper alloy, silver-indium-gold alloy, silver-bismuth alloy and silver-gold alloy; () species are as in items (1) to (6) Any of the optical semiconductor devices 201030191. « «The manufacturing method of the XI lead frame, characterized in that the sterling silver layer and The method of manufacturing a lead frame for an optical semiconductor device according to any one of the items (3) to (6), wherein the sterling silver is formed by the method of the present invention. The layer, the intermediate layer, and the skin layer are formed by a plating method. The lead frame for the optical semiconductor device of the present invention is attached to a lead frame for an optical semiconductor in which a pure silver layer is formed, and an arithmetic mean height of a surface of the pure silver layer is " It is in the range of 0.001 to 0.2, and a metal layer having excellent corrosion resistance is formed on the surface layer of 〇〇〇1 or more and 厚度.2 or less (average film thickness), whereby excellent reflection properties of silver can be exhibited. It can improve corrosion resistance (especially corrosion resistance to sulphide corrosion) and prevent migration. Furthermore, since silver cannot avoid the decrease in reflectance in the ultraviolet region below 400 nm, the reflectance of the ultraviolet region, especially 300 nm, can be covered by a metal other than silver or an alloy thereof by a thin percentage. The reflectance is increased to a level of tens of percent, so that it can be used as a lead frame for an optical semiconductor device having excellent reflection characteristics covering the ultraviolet region to the near-infrared region. Further, the manufacturing method of the present invention can be used as a lead frame for an optical semiconductor device for an LED, a photocoupler, a photointerrupter, etc., and the wavelength of light is 300 nm to the near infrared region of the ultraviolet region. A lead frame excellent in reflection characteristics, heat dissipation, corrosion resistance (especially corrosion resistance against sulfidation corrosion), and long-term stability of reflectance. The above and other features and advantages of the present invention will be apparent from the description and appended claims. [Embodiment] FIG. 1 is a schematic cross-sectional view showing an embodiment of a lead frame for an optical semiconductor device according to the present invention. Here, the state in which the optical semiconductor wafer 4 is carried on the lead frame is shown in Fig. 1 (the same applies to Figs. 3 to 8 below). As shown in FIG. 1, the lead frame of the present embodiment is formed with a pure silver layer 2 made of pure silver on the substrate 1. On the surface layer of the pure silver layer 2, a film 3 made of a metal material excellent in resistance is formed. . In the present invention, the arithmetic mean height Ra of the pure silver layer 2 is 0.001 to 0·2 //m, and the thickness of the film 3 is 0.001 " m or more and 0.2 μm or less. The lead frame of the present invention is a lead frame for an optical semiconductor device which is excellent in reflection characteristics in the visible light region, and has excellent corrosion resistance (especially, the corrosion resistance of the vulcanization residue) and migration resistance. The base vessel 1 may, for example, be copper or a copper alloy, aluminum or aluminum alloy, iron or iron alpha gold 4, preferably a metal or alloy selected from the group consisting of copper, copper alloys, and alloys. By using the substrate 1 as a copper or copper alloy, an inscription or an alloy, it is possible to provide a lead frame which is easy to form a film and which contributes to cost reduction. Moreover, since the characteristics of the lead frame which are excellent in electrical conductivity, that is, the thermal conductivity is good, the heat dissipation characteristics are excellent, and the heat energy generated when the illuminant emits light can be smoothly discharged to the outside through the lead frame, so that the illuminating S piece can be expected. Long life and stable long-term reflection characteristics. Further, in the present invention, "the reflection property is good" means that the reflectance is 3% or more in the wavelength of 300 to 400 nm, and is 70% or more in the wavelength of 4 〇〇 to 8 〇〇 nm. The thickness of the layer 2 of sterling silver is preferably 0.2 to 5.0 // m, and more preferably 201030191 〇·5 to 4.0 //m, more preferably rabbit · 3 Λ ·~. from m. If the thickness of the pure silver layer is too thin, the thickness which contributes to the reflectance may not be & in other respects, although it is too thick, it may be saturated, but the cost will become high. By setting the coating thickness of the pure material 2 to the above range, it is possible to inexpensively manufacture without using a precious metal exceeding a required amount. The silver concentration (purity) for forming the pure silver layer is preferably % by mass or more, and more preferably 98% by mass or more.

Fig. 2 is a schematic enlarged cross-sectional view showing a portion in which the pure silver layer 2 is formed on the upper layer of the substrate i, and a portion of the skin layer 3 as the outermost layer is formed on the upper layer. As shown in the figure, the surface of the pure silver layer 2 has a concave-convex shape, indicating that the index of the gross sugar content of the surface, that is, the arithmetic mean height Rajfe is preferably 2 _, and more preferably 〇·〇1 to 0.15 " m, more preferably For 〇.〇5~〇.15. Further, the arithmetic average height Ra is a value measured in accordance with the surface roughness-definition and expression (Β0601·2〇〇1) of the Japanese Industrial Standard (JIS). By setting the arithmetic mean height of the pure silver layer 2 to the above range, the film 3 composed of the metal material excellent in corrosion resistance (especially, the resistance to sulfide corrosion) formed by the outermost layer can be densely formed. Therefore, it is possible to effectively prevent the formation of pinholes or non-covered portions which are likely to occur when the film 3 is formed, and therefore it is possible to form a film excellent in corrosion resistance for various reasons. Further, if Ra is too large, the subsequent wafer mounting step or bonding step is liable to be broken due to the unevenness of the surface layer, and the surface layer of the pure silver layer 2 cannot be stably and uniformly covered by the film 3 as the outermost layer, resulting in formation of a sterling silver layer. The possibility of the exposed part of 2 is higher. As a result, in the process of being used as a lead frame for an optical semiconductor, the pure silver layer 2 is mainly vulcanized and discolored by the sulfur component, resulting in a decrease in reflectance. In order to improve this problem, it is necessary to make the thickness of the outermost layer thicker, so as to give the money, and thus the cost is high, which is not preferable. Further, as the control method of Ra, the amount of the additive added to the pure silver plating solution or the current density at the time of plating is appropriately adjusted. The outermost layer on the base boat 1 as described above forms the film 3 composed of a metal material which prevents discoloration (stagnation) caused by the vulcanization of the pure silver layer 2, thereby ensuring long-term reliability of the silver of the pure silver layer 2. Further, the thickness of the film 3 (the average film thickness: the arithmetic mean value of the thickness measured at 1 〇 4 in the film) is 0.001 / zm or more and 0.2 or less. If the thickness of the outermost layer is too thin, a sufficient resistance to the surname effect cannot be obtained, and if the thickness is too large, the reflectance of the silver which contributes to the light reflection cannot be performed, and thus the reflectance is drastically lowered in the entire region. If the influence of the arithmetic mean height is also taken into consideration, the average film thickness of the film 3 is thicker than that of the 〇1 "claw" when the reflectance starts to decrease substantially. However, if the thickness is up to 0.2, the layer can be sufficiently lowered. (Thickness of the reflectance of silver in the layer of pure silver 2) If the thickness of the coating exceeds 〇2 Am, it will exhibit a change like the critical point at which the reflectance drops sharply. Therefore, in the present invention, it is more important that 被〇〇1~〇2 "The cover of the melon is densely and uniformly coated. In order to keep the reflectance of the pure silver layer 2 high, the thickness of the film 3 is preferably 〇·0〇5~〇! Preferably, the skin medium composed of a metal material having excellent corrosion resistance as the outermost layer is preferably a layer composed of a metal material which is hard to react with sulfur, carbon or oxygen, and which is less likely to cause discoloration and has a resistance to metal. As a metal material such as η, it is selected from the group consisting of gold, gold alloy, silver alloy, platinum, alloy, gold, nickel, nickel alloy, cobalt, cobalt alloy, palladium, palladium alloy, rhodium, nail man gold 201030191 姥姥Alloy, silver, drum alloy, And a metal material in the group consisting of indium alloys, more preferably selected from the group consisting of gold, gold alloys, silver alloys, and money, gold, indium, and indium alloys + for forming the corrosion resistance of the film 3 as the outermost layer. When the excellent metal material is silver mouth gold, the silver alloy is preferably selected from the group consisting of silver-tin alloy, silver-copper alloy, silver-indium alloy, silver, alloy, silver sulphide alloy, silver gold gilt a silver alloy in a group consisting of an alloy, a silver alloy, and the like, and is preferably a silver alloy selected from the group consisting of silver, copper alloy, silver indium alloy, silver-bismuth alloy, and silver-gold alloy. The silver reflectance can be more effectively utilized as a silver alloy, which can be manufactured relatively inexpensively. In particular, it is relatively easy to form the above-mentioned gold with the addition of $μ, +, & i α, and the anti-rust treatment effect and reflection The film 3 which is the outermost layer may have a thickness (average film thickness) within the above range, and the number of layers is not defined. For example, the Au layer may be a 〇〇〇5 core, and the upper layer may be a layer. Set to (4) 5 However, 1 is considered to be productive or cost-like. The lead frame of the present invention is equipped with an optical semiconductor wafer 4, and is connected to an external wiring to supply electric power to the optical semiconductor 4 from the outside, and molds the optical semiconductor wafer 4 and its surroundings with a resin to form an optical semiconductor device. The formation portion of the film 3 must be formed at least in the portion where the optical semiconductor wafer* is mounted. In other words, the film 3 is formed in addition to the place where the optical semiconductor wafer 4 is mounted. This is because the mounting portion of the optical semiconductor wafer 4 is used only. The formation of the film 3 prevents the discoloration of the pure silver layer 2 having the function of the reflecting plate, and does not greatly affect the reflection characteristics, and the four columns such as the portion 11 of the mold resin can be the outermost layer of the pure silver layer 3. Therefore, The formed film 3 13⁄4 can be formed, for example, by partial plating such as strip-shaped electric forging or point-shaped electric chain. The manufacture of a partially formed lead frame can reduce the use of metal as an excess, thus providing a light guide for light and environmentally friendly. Further, as the semiconductor wafer 4, any light half such as an LED element can be used. FIG. 3 is another embodiment of the lead frame for an optical semiconductor device of the present invention.

A schematic cross-sectional view of the present invention has an intermediate layer 5 formed between the base 2 and the sterling silver layer 2 for the lead frame of the aspect shown in FIG. In addition, in the drawings, the symbols which are not specifically mentioned are the same as the symbols in the figure i (the same applies to the following figures). The intermediate layer 5 is preferably made of a metal or alloy selected from the group consisting of recording, recording alloys, alloys, alloys, copper, and copper alloys. The light-emitting element can be prevented by providing an intermediate layer 5 composed of a recorded or recorded alloy, a drilled or drilled alloy, copper or a copper alloy between the pure silver layer 2 and the substrate i.

The heat generation causes deterioration of the reflection characteristics caused by the diffusion of the base Zhao, so that the reflection characteristics are more reliable in the long term. The thickness of the intermediate layer 5 is not particularly limited, but it is preferably 0.2 to 2 // m, more preferably 0.5 to 1 # m, in consideration of 々 生成 f generation, productivity, and heat resistance. There is no special rule for the number of layers, but if it is also considered to be productive, it is usually 1 layer. 4 is a schematic cross-sectional view of a lead frame for an optical semiconductor device according to the present invention, and shows a case where only the film 3 composed of a metal material having excellent corrosion resistance is mounted on the optical semiconductor wafer 12 201030191. . Fig. 5 is a schematic cross-sectional view showing another embodiment of a lead frame for an optical semiconductor device according to the present invention, and a film 3 made of a metal material excellent in resistance to money is formed only in a portion where the optical semiconductor crystal #4 is mounted, and is formed. There is an intermediate layer 5. Fig. 6 is a schematic cross-sectional view of a lead frame for an optical semiconductor device similar to that shown in Fig. 3. The optical semiconductor wafer 4 is mounted on both surfaces of the lead frame. As shown in the 'samples', it is also possible to use not only one side but also two sides to form an optical semiconductor device. 10 ® 7 series, a light cross-section of the present invention, a schematic cross-sectional view of another embodiment of the wire frame, The optical semiconductor wafer 4 is mounted on the base 1 and the optical semiconductor wafer 4 is mounted on the inside of the recess. As the shape, the lead frame for the optical semiconductor device of the present invention can of course be adapted to the recessed portion to improve the shape of the concentrating lead frame. Fig. 8 is a cross-sectional view showing a lead frame for an optical semiconductor device according to the present invention, in which a concave portion is provided in a base 1 and a photo-semiconductor is mounted on the inside of the concave portion, and only the outermost layer 3 is formed only in the concave portion. The portion that contributes to the reflection of the light emitted by the photo-semiconductor is applied to the outermost layer, and can be suitably used to improve the corrosion resistance of the reflective portion. The lead frame for the optical semiconductor device can be manufactured by any method, but the sterling silver layer 2 The film 3 and the intermediate layer 5 composed of a metal material excellent in resistance to the surname are preferably formed by electroplating. The electroplating method can be easily adjusted in thickness and cost compared with the cladding method or the sputtering method. [Embodiment] Hereinafter, the present invention will be described in more detail based on the examples, but the present invention is not limited thereto. The "base layer" is synonymous with the above "intermediate layer". Example 1 After the following pretreatment was carried out on the substrate shown in Table 1 having a thickness of 0.3 mm and a width of 50 mm, the present invention was carried out by the following plating treatment to obtain Examples 1 to 39 of the present invention having the constitution shown in FIG. Example i and lead frames of comparative examples i and 2. The layers of the lead frames are formed in the order of the substrate, the pure silver layer, and the outermost layer in the examples i to 6 of the present invention, and the conventional examples are formed by the order of the substrate, the base layer, and the pure silver layer. 7 to 39 and Comparative Examples i and 2 are formed in the order of the substrate, the underlayer, the sterling silver layer, and the outermost layer film. ❹ Further, the pure silver layer is formed into a thickness in all cases by the following Ag plating conditions, and is contacted with a surface roughness meter before the formation of the outermost layer film (SURFCORDER SE_3〇H (trade name) : (Stock) Kosaka Research Institute) The result of measuring the surface roughness is 'arithmetic average height gauge &=〇12 Vm. Further, among the materials used for the substrate, "C11000", "C26800", "C52100", "C77000", and "C19400" indicate copper or copper alloy bases. The numerical value after C is based on cDA (Copper Development).

Association 'Bronze Development Association' specifications. Further, r EFteC-3" is a copper alloy manufactured by Furukawa Electric Co., Ltd., which is a copper alloy shown by "C14410" in the CDA specification. Further, "A1100", "A2014", "A3003", and "A5052" indicate the base of the Ming or Ming alloy, and the numerical values after A indicate the types based on JIS. In addition, "SUS3 04" and "42 alloy" are ferroalloy bases, "SUS304" is a stainless steel of the corresponding type specified by JIS, and "42-in 14 201030191 gold" is a ferroal alloy containing 42% of Ni. The pretreatment is carried out by electrolytic degreasing of the copper substrate, the copper alloy substrate and the iron alloy substrate ' in the substrate, followed by the following pickling. Further, the aluminum base and the aluminum alloy base were subjected to the following electrolytic degreasing, followed by the following pickling, and then the following zinc substitution was carried out. Further, pre-plating of silver is performed at a thickness of 0_01 //m before the formation of the pure silver plating layer. The preprocessing conditions are indicated below. (Pre-treatment conditions) Φ [Electrolytic degreasing] Degreasing liquid: NaOH 60 g / liter Degreasing conditions: 2·5 A/dm2, temperature 6 (TC, degreasing time 60 seconds [acid washing] Pickling liquid: 10% sulfuric acid pickling conditions :3 leptosecond impregnation, room temperature [zinc substitution] When the matrix is aluminum, use zinc substitution solution: NaOH 500 g / liter, ZnO 100 g / liter, tartaric acid φ (C: 4H606) 10 g / liter, FeCl2 2 g / liter treatment conditions: 3 leap seconds impregnation, room temperature [Ag pre-plating] coating thickness 〇. 〇 1 to m electro-mineral: KAg (CN) 2 5 g / liter, KCN 60 g / liter, ore conditions: Current density 2 A/dm2, plating time 4 seconds, temperature 25

°C The following shows the plating composition and plating conditions of each plating used. [Ag plating] coating thickness! , 〇 m m 15 201030191 Plating solution: AgCN 50 g / liter, KCN 100 g / liter, K2C 〇 3 3 〇 g / liter electric forging conditions: current density i A / dm2, temperature 3 (rc, processing time 96 seconds [ Ni plating] Plating solution: Ni(S03NH2)2 · 4H20 500 g/L, NiCl2 3〇g/L, H3B〇3 30 g/L Plating conditions: current density 5 A/dm2, temperature 50°c [Co plating] Plating solution: Co(S03NH2)2· 4H20 500 g/liter, c〇Cl2 30 g/liter, H3B〇3 30 g/liter plating conditions: current density 5 A/dm2, temperature 5 〇 ° C [Cu plating] plating Liquid: CuS04 · 5H20 250 g / liter, H2S04 50 g / liter, NaCl 〇 · 1 g / liter plating conditions: current density 6 A / dm2, temperature 4 〇. 〇 [In plating] plating solution: InCl3 45 g / liter , KCN 150 g / liter, KOH 35 g / liter, dextrin 35 g / liter electro-minening conditions: current density 2 A / dm2, temperature 20 ° C [Au plating] plating solution: KAu (CN) 2 14.6 g / liter , c6H8〇7 150 g/liter, K2C6H4〇7 180 g/liter

Plating conditions: current density i A/dm2, temperature 4 (TC 201030191 [Au-Co plating] Au-0.3% Co plating bath: KAu (CN) 2 14.6 g / liter, c6H8 〇 7 15 〇 g / liter, K2C6H407 180 g / liter, EDTA_Co (II) 3 g / liter, piperazine 2 g / liter electric bond conditions: current density 1 A / dm2, temperature 4 〇 t [Ag-Cu alloy plating] Ag-20%Cu electric fluid: AgCN 2.5 g / liter, CuCN 70 g / liter, KCN 6 〇 g / liter, K2CO3 20 g / liter plating conditions: current density 0.5 A / drn2, temperature 5 〇〇 c 〇 [Ag-In alloy plating] Ag-10% In plating solution: KCN 100 g / liter, NaOH 50 g / liter ' AgCN 10 g / liter, I11CI3 20 g / liter electro-minening conditions: current density 2 A / dm2, temperature 3 〇 ° c [Pt plating] Keychain: Pt(N02)2(NH3)2 10 g/L, NaN02 10 g/L, nh4no3 100 g/L, NH3 50 ml/L electric clock Condition: Current density 5 A/dm2, temperature 90 °C ® [Rh electricity Clock] Electric forging liquid. RHODEX (trade name, manufactured by Japan Electroplating Engineers Co., Ltd.) Plating conditions: 1.3 A/dm2, temperature 50. 〇 [Sn plating]

Plating solution: SnS04 80 g / liter ' H2S04 80 g / liter of electro-minening conditions: current density 2 A / dm2, temperature 30 ° C [Ni-P alloy plating] Ni-3%P 17 201030191 plating solution · NiS 〇 4 20 g / liter, NaH2P 〇 2 25 g / liter, C3H603 25 g / liter ' C3H6 〇 2 3 g / liter record conditions: electroless mine, temperature 9 〇. 〇[Pd plating] Electron ore: Pd(NH3)2Cl2 45 g/L, NH4OH 90 ml/L, (NH4)2S04 50 g/L Plating conditions: Current density 1 A/dm2, temperature 30 °C [Pd- Ni alloy plating] Pd-20%Ni plating solution · Pd(NH3)2Cl2 40 g/liter, NiS〇4 45 g/liter, NH4OH 90 ml/liter, (NH4)2S04 50 g/liter plating conditions: current density 1 A/dm2, temperature 3 (TC [Ag-Pd alloy plating] Ag-10°/〇Pd plating bath: KAg[CN]2 20 g/liter, PdCl2 25 g/liter, Κ407Ρ2 60 g/liter, KSCN 150 g / Li plating conditions: current density 〇 · 5 A / dm2, temperature 40 ° C [Ru plating]

Plating solution: RuNOC13 · 5H20 l〇g / liter, nH2s 〇 3H 15 g / liter plating conditions: current density 1 A / dm2, temperature 5 〇 ° C For the obtained lead frame of the present invention, comparative examples and previous examples, Evaluation was performed by the following tests and benchmarks. (1) Reflectance: in spectrophotometer ((share) Hitachi

The total reflectance was continuously measured from 300 nm to 800 nm in the product of High-Technologies, trade name: υ-4100). Among them, the reflectance (%) in 3 〇〇 nm, 500 nm, and 800 nm is shown in Table 2. Here, the reflectance of the wavelength 3 〇〇 ηηι 201030191 is 30% or more, and the reflectance of the wavelengths of 500 nm and 800 nm is 70% or more, which is judged to be a practical grade. (2) Corrosion resistance: For the vulcanization test (JIS η 8502), the corrosion state of the H2S after 3 ppm ' 24 h was evaluated by Rating Number (RN). The results are shown in Table 2. Here, 'is a good grade of corrosion resistance, and when RN is 9 or more, it is judged that long-term reliability is good. (3) Heat dissipation (thermal conductivity): When the conductivity of the substrate is 1 G% or more in accordance with IACS (International Annealed Copper Standard), it is considered to be high in thermal conductivity and will be "&". Less than 10% are considered as thermal conductivity 鲂 you 1 ^ r

It is not a denial of its practicality.

Xj ' is also shown in Table 2»The ratio of the ratio of I, IACS has better I conductivity and heat dissipation is better than 'even if the thermal conductivity is lower. 201030191 [Table i] Base substrate layer thickness (μ m) Surface layer film top layer thickness (μm) Inventive Example 1 EFTEC-3 - In 0.0015 Inventive Example 2 EFTEC-3 - In Inventive Example 3 EFTEC-3 - In 0.025 Inventive Example 4 EFTEC-3 - - In 0.048 Inventive Example 5 EFTEC-3 - In · * 0.1 Inventive Example 6 EFTEC-3 - In 0.19 Inventive Example 7 EFTEC-3 Ni 0.51 In 0.054 Inventive Example 8 EFTEC-3 Co 0.55 In 0.049 Inventive Example 9 EFTEC-3 Cu 0.48 In 0.052 Inventive Example 10 C11000 Ni 0.54 In 0.053 Inventive Example 11 C26800 Ni 0.49 In 0.051 Inventive Example 12 C52100 Ni 0.49 In 0.048 Inventive Example 13 C77000 Ni 0.57 In 0.049 Inventive Example 14 C19400 Ni 0.52 In 0.048 Inventive Example 15 EFTEC-3 Ni 0.53 Au 0.051 Inventive Example 16 EFTEC-3 Ni 0.53 Au-Co 0.053 Inventive Example 17 EFTEC-3 Ni 0.54 Ag-Cu 0.054 Inventive Example 18 EFTEC-3 Ni 0.51 Ag-In 0.052 Inventive Example 19 EFTEC-3 Ni 0.52 Pt 0.0013 EXAMPLE 20 EFTEC-3 Ni 0.55 Pt 0.008 Inventive Example 21 EFTEC-3 Ni 0.5 Pt 0.021 Inventive Example 22 EFTEC-3 Ni 0.51 Pt 0.053 Inventive Example 23 EFTEC-3 Ni 0.52 Pt 0.097 Inventive Example 24 EFTEC-3 Ni 0.55 Pt 0.195 Inventive Example 25 A1100 Ni 0.51 Au 0.048 Inventive Example 26 A2014 Ni 0.52 Au 0.048 Inventive Example 27 A3003 Ni 0.52 Au 0.046 Inventive Example 28 A5052 Ni 0.51 Au 0.051 Inventive Example 29 EFTEC-3 Ni 0.52 Rh 0.05 Inventive Example 30 EFTEC-3 Ni 0.56 Sn 0.052 Inventive Example 31 EFTEC-3 Ni 0.46 Ni 0.05 Inventive Example 32 EFTEC-3 Ni 0.51 Ni-P 0.052 Inventive Example 33 EFTEC-3 Ni 0.47 Co 0.05 Inventive Example 34 EFTEC-3 Ni 0.5 Pd 0.048 Inventive Example 35 EFTEC-3 Ni 0.53 Pd-Ni 0.051 Inventive Example 36 EFTEC-3 Ni 0.53 Ag-Pd 0.051 Inventive Example 37 EFTEC-3 Ni 0.48 Ru 0.054 Inventive Example 38 SUS304 Ni 0.46 Pt 0.11 Inventive Example 39 42 Alloy Ni 0.49 Pt 0.13 Comparative Example 1 EFTEC-3 Ni 0.51 Pd 0.0005 Comparative Example 2 EFTEC-3 Ni 0.55 Pd 0.21 Previous Example 1 EFTEC-3 Ni 2.05 — — 20 201030191 [Table 2]

@300 nm @500 nm @800 nm RN Heat dissipation Example 1 of the invention 35 89 91 9.3 〇 Inventive Example 2 39 86 88 9.5 〇 Inventive Example 3 42 83 88 9.8 〇 Inventive Example 4 48 82 87 10 〇 The present invention Example 5 55 79 88 10 〇 Inventive Example 6 65 77 85 10 〇 Inventive Example 7 48 80 86 9.8 〇 Inventive Example 8 48 81 85 10 〇 Inventive Example 9 49 78 87 10 〇 Inventive Example 10 47 83 88 9.8 〇 Inventive Example 11 48 83 86 10 〇 Inventive Example 12 46 83 87 9.8 〇 Inventive Example 13 46 84 86 10 〇 Inventive Example 14 48 84 87 10 〇 Inventive Example 15 43 80 90 9.8 〇 Inventive Example 16 44 81 90 9.5 〇 Inventive Example 17 36 78 88 9.8 〇 Inventive Example 18 45 83 90 9.8 〇 Inventive Example 19 32 90 92 9 〇 Inventive Example 20 37 88 90 9.5 〇 Inventive Example 21 40 84 88 10发明 Inventive Example 22 43 82 85 9.8 〇 Inventive Example 23 46 80 81 10 〇 Inventive Example 24 50 77 79 10 〇 Inventive Example 25 40 82 88 9.8 〇 Inventive Example 26 38 82 87 9.5 〇 Inventive Example 27 39 83 87 9.8 〇 Inventive Example 28 40 81 86 9.8 〇 Inventive Example 29 50 78 84 10 〇 Inventive Example 30 56 76 78 9.8 〇 Inventive Example 31 40 73 79 9.8 〇 Inventive Example 32 38 73 79 9.8 〇 Inventive Example 33 40 72 78 9.8 〇 Inventive Example 34 45 70 75 10 〇 Inventive Example 35 40 72 74 9.8 〇 Inventive Example 36 33 73 77 9.8 〇 Inventive Example 37 40 70 72 9.8 〇 Inventive Example 38 46 79 81 9.8 X Inventive Example 39 46 80 81 9.8 X Comparative Example 1 25 80 85 5 〇 Comparative Example 2 47 51 66 10 〇Previous Example 1 8 93 98 2 〇21 201030191 The thickness of the base layer and the thickness of the outermost layer shown in Table 1 are the average values (the arithmetic mean of the measured values at any 10 points). From the results shown in Table 2, it can be clarified that 'pure silver is provided on copper or copper alloy, aluminum or aluminum alloy; I' is on it and is provided with a metal having excellent resistance to rice in the range of thickness specified by the present invention. A film of material composition whereby the reflectivity characteristic, in particular the reflectance at 300 nm, is improved from the previous percentage of silver to a tens of percent. This case can be applied to the use of optical semiconductors of such wavelengths by an increase in the reflectance of the ultraviolet region. Moreover, it can be seen that if the thickness of the film on the outermost layer is too thick, the light will not reach the pure silver layer. Therefore, the optical properties of the outermost layer are strong, so that the good reflection characteristics of the visible light of pure silver will disappear, and thus it is lower than practical. 70% of the grade 〇 Regarding the heat dissipation characteristics, when a metal having a good electrical conductivity or an alloy thereof is used as a lead frame base, it is preferable to iron or an iron alloy (Examples 38 and 39 of the present invention). Further, the lead frames of Inventive Examples 38 and 39 are suitable for applications requiring more mechanical strength than heat dissipation. Example 2 ^ On a copper alloy composed of C19400 having a thickness of 0.15 mm and a width of 30 mm, a nickel plating layer as a base layer was formed to a thickness of 1.0 μm, and a pure silver layer was formed on the upper layer, and the thickness was as shown in Table 3. The lead frame of Examples 40 to 63 and Comparative Examples 3 to 7 of the present invention was formed as the Pt plating layer as the outermost layer. The plating procedure or liquid composition was the same as that of the procedure of Example 1, and for the formation of a pure silver layer, gloss silver plating and matt silver plating were used. Further, when the Ra of the sterling silver layer and the plating thickness are adjusted, the current density is adjusted under the conditions of 0.1 to 10 A/dm 2 in the gloss silver plating and the matte silver plating 22 201030191. In addition, the Ra of the pure silver layer was measured by a contact surface roughness meter (SURFCORDER SE-30H (trade name): manufactured by Kosaka Research Institute) in the same manner as in the example. [Gloss Ag plating] Electron ore: AgCN 50 g / liter, KCN 1 〇〇 g / liter, k2C03 30 g / liter ' Na2S203 5 g / liter plating conditions: current density 2 ~ l 〇 A / dm2, temperature 30t: ❹ [matte Ag key] Electron ore: AgCN 50 g / liter, KCN 1 〇〇 g / liter, k2C03 30 g / liter Key conditions: current density 〇 1~5 A / dm2, temperature 3 〇χ: The lead frame of the obtained invention examples and comparative examples was measured for reflectance and resistance to the surname in the same manner as in the first embodiment. These results are shown together in Table 3.

23 201030191 [Table 3] Thickness of pure silver layer coating (/zm) Ra(/m) Thickness of the outermost layer ((iv) Reflectance (%) Financial RN @300 nm @500 nm @800 nm Inventive Example 40 0.21 0.120 0.008 38 82 87 9.5 Inventive Example 41 0.52 0.126 0.009 37 87 89 9.5 Inventive Example 42 0.98 0.124 0.008 38 88 90 9.5 Inventive Example 43 2.95 0.128 0.009 37 88 89 9.5 Inventive Example 44 3.90 0.124 0.008 38 87 90 9.5 Inventive Example 45 4.80 0.125 0.008 38 88 89 9.5 Inventive Example 46 1.06 0.002 0.009 38 88 90 10 Inventive Example 47 0.98 0.009 0.008 37 88 90 10 Inventive Example 48 1.01 0.048 0.009 38 87 89 10 Inventive Example 49 1.03 0.095 0.008 37 88 90 9.5 Inventive Example 50 0.98 0.148 0.008 38 87 89 9.3 Inventive Example 51 1.10 0.197 0.009 37 88 89 9 Inventive Example 52 2.45 0.048 0.001 32 90 92 9.5 Inventive Example 53 2.53 0.050 0.009 35 86 90 9.8 Inventive Example 54 2.52 0.047 0.048 43 82 85 10 Inventive Example 55 2.50 0.049 0.149 48 80 82 10 Inventive Example 56 2.49 0.050 0.197 50 ΊΊ 79 10 Inventive Example 57 2.54 0.195 0.001 31 90 91 9 Inventive Example 58 2.47 0.199 0.010 33 84 89 9.3 This hair Example 59 2.51 0.200 0.046 41 82 85 9.5 Inventive Example 60 2.50 0.198 0.146 48 80 82 9.8 Inventive Example 61 2.52 0.196 0.191 50 76 78 10 Inventive Example 62 0.08 0.123 0.048 40 73 79 9.8 Inventive Example 63 5.51 0.122 0.050 42 79 83 9.8 Comparative Example 3 1.10 0.231 0.001 32 88 89 7 Comparative Example 4 1.05 0.230 0.008 33 84 89 7 Comparative Example 5 1.08 0.235 0.047 41 82 95 7 Comparative Example 6 0.98 0.233 0.148 48 80 82 8 Comparative Example 7 1.00 0.230 0.196 50 76 78 8 It is clear from the results shown in Table 3 that if Ra is within the range specified by the present invention, the reflection characteristics are good and the corrosion resistance is also excellent. However, if Ra is too large, the uneven portion cannot be completely covered with the outermost layer, and the pure silver portion is exposed, and the corrosion resistance is considered to be lowered. Therefore, Ra is more useful for mounting a portion of the optical semiconductor lead frame within the range defined by the present invention. 24 201030191 The present invention has been described in connection with this embodiment, but it is not intended to limit the invention in any detail as long as it is not specifically described, and should not deviate from the scope of the attached patent application. The invention is broadly construed in the spirit and scope of the invention. The present application claims priority to Japanese Patent Application No. 2008-324. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing an embodiment of a lead frame for an optical semiconductor device according to the present invention. Fig. 2 is a schematic enlarged cross-sectional view showing a portion in which a pure silver layer 2 is formed on the upper layer of the substrate, and a portion of the film 3 which becomes the outermost layer is formed on the upper layer. Fig. 3 is a schematic cross-sectional view showing another embodiment of a lead frame for an optical semiconductor device of the present invention. Fig. 4 is a schematic cross-sectional view showing still another embodiment of the lead frame for an optical semiconductor device of the present invention. Fig. 5 is a schematic cross-sectional view showing still another embodiment of the lead frame for an optical semiconductor device of the present invention. Fig. 6 is a schematic cross-sectional view showing still another embodiment of the lead frame for an optical semiconductor device of the present invention. A schematic cross-sectional view showing still another embodiment of the lead frame for an optical semiconductor device of the present invention. Fig. 8 is a schematic cross-sectional view showing another embodiment of the lead frame for an optical semiconductor device according to the present invention. [Main component symbol description] 1 Base 2 Pure silver layer 3 Film made of metal material with excellent corrosion resistance 4 Optical semiconductor wafer 5 Intermediate layer 26

Claims (1)

201030191 VII. Patent application scope: sterling silver=species 1 semiconductor device material, (4), which has formed a pure silver layer composed of !: on the base body, characterized in that the arithmetic mean latitude Ra of the sterling silver layer is 0.001~〇 7 m, and formed on the surface thereof, a gold-based bismuth metal material excellent in durability to vulcanized rot, and a film having an average film thickness of G.GG1 or more and 〇.2 em or less. For example, in the optical semiconductor device of the patent scope of the present invention, the wire base frame is composed of a metal or alloy selected from the group consisting of steel, copper alloy, aluminum and aluminum alloy. A lead frame for an optical semiconductor device according to claim 1 or 2, wherein at least a tantalum layer, free nickel, nickel alloy, cobalt, cobalt alloy, copper and copper alloy is formed between the substrate and the pure silver layer. An intermediate layer of a metal or alloy in the group. 4' The thickness of the sterling silver layer in the lead frame of the optical semiconductor device of the first to the third item of the application (4) is G.2 to 5.0 μm. The invention relates to a green semiconductor device for use in an optical semiconductor device according to any one of claims 1 to 4, wherein the metal material forming the film is selected from the group consisting of gold, gold, gold, and silver alloy. A metal or alloy in a group consisting of platinum, platinum alloys, rhodium, ruthenium alloys, indium, and indium alloys. 6. The guide for optical semiconductor devices according to any one of claims 1 to 5, wherein the metal material forming the film is selected from the group consisting of silver-copper alloy, & A A silver alloy in a group consisting of an indium alloy, a silver-bismuth alloy, and a silver-gold alloy. 7. A method of manufacturing a lead frame for a light semiconductor device, which is used for manufacturing a lead frame for an optical semiconductor device according to any one of claims 1 to 6 of the invention, characterized in that the sterling silver The layer and the film are formed by a bonding method. 4. The method of manufacturing a lead frame for a light semiconductor device, which is used for manufacturing the lead frame for optical semiconductors according to any one of claims 3 to 6, characterized in that the silver layer is The intermediate layer and the film are formed by electroplating. Eight, (such as the next page) 28