JP2016029725A - Substrate for mounting semiconductor light-emitting element, and semiconductor light-emitting element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate for mounting a semiconductor light-emitting element, capable of securing high reflectivity without being sulfurized, and to provide a semiconductor light-emitting device using the same.SOLUTION: A substrate for mounting a semiconductor light-emitting element includes: a base material 2 comprising a metal part; and an aluminum reflective layer 4 having a thickness of 0.02 μm or more and 5 μm or less, which is provided on the surface side of the base material 2 on which the semiconductor light-emitting element is mounted. In the aluminum reflective layer 4, the impurity carbon concentration is 1×10pcs/cmor more and 1×10pcs/cmor less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a substrate for mounting a semiconductor light emitting element and a semiconductor light emitting device using the same.

  Generally, a semiconductor light emitting device represented by a light emitting diode (LED) or a laser diode (LD) is an LED chip or an LD chip on a metal substrate represented by copper or a metal resin composite substrate. The LED chip or the LD chip and a part of the base material are surrounded by an envelope made of, for example, a mold resin. The part exposed from the envelope of the base material becomes one external terminal, and the other external terminal has one end in the envelope and is electrically connected to the LED chip or the LD chip by, for example, a bonding wire.

  In order to efficiently extract the light generated by the LED chip or LD chip to the outside, the semiconductor light emitting device having such a configuration is provided with a silver plating layer having a high light reflectance on the surface of the substrate on which the LED chip or LD chip is mounted. It is known that the light emitted to the back surface (base material) side of the LED chip or LD chip is reflected to the extraction side (Patent Document 1), and the LED chip or LD is used as the envelope. An opening having a so-called inclined surface that separates from the LED chip or the LD chip is formed around the chip, and a metal layer selected from silver, silver bismuth, and silver neodymium having high light reflectivity is formed on the inclined surface. Forming and reflecting the light emitted laterally from the LED chip or LD chip in the direction of the exit of the opening, and covering the metal layer with a resin layer having a high gas barrier property, sulfurized gas Gas in the atmosphere enters and reacts with silver is known to prevent the lowering the blackened reflectance are (Patent Document 2).

JP 2007-149823 A JP 2010-10279

In the semiconductor light-emitting device described in Patent Document 1, the resin used as the envelope allows gas in the atmosphere such as hydrogen sulfide to pass therethrough, and these gases react with the silver plating layer to cause sulfurization and the like, and blackening Therefore, there is a problem that the reflectance of the silver plating layer is rapidly reduced. The semiconductor light emitting device described in Patent Document 2 discloses a method for solving the problem of Patent Document 1, but there is a problem that the range is limited due to the heat resistance of the envelope resin material. As described in Patent Document 2.
Further, as another method for solving the problem of Patent Document 1, it has been proposed to apply a thin organic protective film for preventing sulfidation on the surface of the silver plating layer. However, there is a problem that the protective effect is lost due to deterioration or peeling of the protective layer due to plasma cleaning or the like performed to stabilize wire bonding before wire bonding.

One object of the present invention is to provide a substrate for mounting a semiconductor light-emitting element capable of ensuring a high reflectance without being sulfided.
Another object of the present invention is to provide a semiconductor light emitting device capable of ensuring a high reflectance without being sulfided.
Other objects of the present invention will become clear from the description of the embodiments and examples.

  In order to achieve the above object, according to the first aspect of the present invention, a thickness of 0.02 μm or more and 5 μm or less provided on the surface side on which the base material composed of a metal portion and the semiconductor light emitting element of the base material are mounted. Provided is a substrate for mounting a semiconductor light emitting device, comprising an aluminum reflective layer.

  In order to achieve the above object, the second aspect of the present invention has a thickness of 0.01 μm or more and 5 μm or less provided on the substrate side comprising the metal portion and the surface of the substrate on which the semiconductor light emitting element is mounted. Provided is a substrate for mounting a semiconductor light emitting device, comprising: a silver layer or a silver alloy layer; and an aluminum reflective layer having a thickness of 0.006 μm or more and 2 μm or less provided on the silver layer or the silver alloy layer.

  In order to achieve the above object, according to a third aspect of the present invention, there is provided a semiconductor light emitting element mounting substrate, a semiconductor light emitting element mounted on the semiconductor light emitting element mounting substrate, and the semiconductor light emitting element mounting substrate. An envelope portion having a concave portion formed by an inclined surface or a vertical surface that is separated from the semiconductor light emitting element as it is separated from the semiconductor light emitting element mounting substrate. Provided is a semiconductor light emitting device including a light transmissive resin portion that fills the concave portion of the envelope portion and seals the semiconductor light emitting element.

  According to the present invention, since the aluminum reflective layer is formed on the surface of the base material, it is possible to realize a semiconductor light emitting element mounting substrate having high and stable reflection characteristics over a long period without being sulfided and a semiconductor light emitting device using the same. . The reflectivity of aluminum is 3 times higher than that of silver in ultraviolet rays, and it has a reflectivity close to silver for purple, red, and infrared rays. This is due to the fact that it has a high reflectivity and has superior chemical resistance compared to silver and is less susceptible to sulfidation.

1 is a schematic cross-sectional view of a semiconductor light-emitting element mounting substrate showing a first embodiment of the present invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 2nd Embodiment of this invention. It is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 3rd Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 4th Embodiment of this invention. (A)-(d) is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 5th Embodiment of this invention. (A)-(c) is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 6th Embodiment of this invention. (A)-(e) is a schematic sectional drawing of the semiconductor light-emitting element mounting substrate and semiconductor light-emitting device which show the 7th Embodiment of this invention. It is the schematic which shows the typical use condition of a semiconductor light-emitting device as the 8th Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 10th Embodiment of this invention. It is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 11th Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 12th Embodiment of this invention. It is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 13th Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 14th Embodiment of this invention. (A)-(d) is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 15th Embodiment of this invention. (A)-(c) is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 16th Embodiment of this invention. (A)-(d) is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 17th Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 18th Embodiment of this invention. (A)-(c) is the schematic which shows the typical use condition of the semiconductor light-emitting device which is the 19th Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting element mounting substrate and semiconductor light-emitting device which are the 21st Embodiment of this invention. (A) is a schematic cross-sectional view of a substrate for mounting a semiconductor light emitting device showing a twenty-first (1) embodiment of the present invention, and (B) is a semiconductor showing a twenty-second (2) embodiment of the present invention. It is a schematic sectional drawing of the light emitting element mounting substrate. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 23rd Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light emitting element mounting substrate which shows the 24th Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 25th Embodiment of this invention. (A)-(d) is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 26th Embodiment of this invention. (A)-(c) is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 27th Embodiment of this invention. (A)-(e) is a schematic sectional drawing of the semiconductor light-emitting device mounting substrate and semiconductor light-emitting device which show the 28th Embodiment of this invention. (A)-(c) is the schematic which shows the typical use condition of a semiconductor light-emitting device as the 29th Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 31st Embodiment of this invention. It is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 32nd Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 33rd Embodiment of this invention. (A)-(d) is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 34th Embodiment of this invention. (A)-(d) is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which shows the 35th Embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device which shows the 38th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each figure, about the component which has the substantially same function, the same code | symbol is attached | subjected and the duplicate description is abbreviate | omitted. Examples 3-7, 21, 24, 25, 11, 28, 36-38, 47 are reference examples.

(First to tenth embodiments)
Embodiments of a semiconductor light-emitting element mounting substrate and a semiconductor light-emitting device according to the present invention include at least one of a base material made of copper, a copper alloy, or an iron-based alloy on which a semiconductor light-emitting element is mounted and a surface on which the semiconductor light-emitting element is mounted. A substrate for mounting a semiconductor light emitting element is constituted by an aluminum reflective layer provided in the part.

  The semiconductor light-emitting device includes at least a base material made of metal and an aluminum reflective layer provided on at least a part of a surface of the base material on which the semiconductor light-emitting device is mounted.

  As the metal of the base material, a base material made of copper or a copper alloy is desirable in terms of electric resistance and thermal resistance. Further, as the metal of the base plate, an iron nickel alloy such as 42 alloy or an iron-based frame material can be used.

  Furthermore, the base material should just contain the metal part. For example, the base material can be a copper-clad plate in which copper is laminated on a resin. In this case, the resin is formed on the surface opposite to the surface on which the aluminum reflective layer is formed on the substrate. Furthermore, the surface of the base material on the side opposite to the surface on which the aluminum reflective layer is formed may include a composite structure composed of an organic material and an inorganic material.

[First Embodiment]
FIG. 1 is a schematic cross-sectional view of a semiconductor light emitting element mounting substrate according to a first embodiment of the present invention, in which 2 is a base material, and 4 is a region including a portion where a semiconductor light emitting element on one surface of the base material 2 is mounted. The semiconductor light-emitting element mounting substrate is composed of the aluminum reflective layer formed on the substrate.

  The base material 2 is comprised with the composite material of a metal or a metal, and an organic material or an inorganic material. The metal material is not limited to this, but the most versatile base material is a metal lead frame made of copper or a copper alloy. When using a copper plate as the base material 2, the thickness is not limited, but the thickness is selected in consideration of cost. In consideration of mass production, a copper plate hoop material is preferable, but short sheet materials and individual materials can also be used. When a composite material is used as the base material 2, a copper clad plate in which a copper plate is laminated on a resin material or a laminate thereof can be used. As the resin, a hard plate-like resin or a thin flexible resin can be used. Typical examples include glass epoxy substrates (glass cloth base resin plates) and polyimide resin systems. The manufacturing method of the aluminum reflective layer 4 is a vapor deposition apparatus having a reduced pressure adjustment function, and is performed by batch processing or continuous processing. The thickness of the aluminum reflective layer 4 is preferably 0.02 μm or more from the viewpoint of reflectivity.

  When a copper plate is used as the base material 2, for example, the length is 100 m, the width is 50 mm, and the thickness is 0.2 mm. The thickness of the aluminum reflective layer 4 is, for example, 0.05 μm. In production, first, a copper plate having the above-described dimensions was prepared as the base material 2. Next, the aluminum reflective layer 4 was formed using a resistance heating type barrel-type vacuum vapor deposition apparatus. Specifically, the base material 2 is cut so as to be a short material of 50 mm × 150 mm, and 16 pieces of the cut base materials are arranged radially on an umbrella-shaped jig having a radius of 300 mm, and three sets are arranged in a barrel. Then, a resistance heating source (output 1 kW) was used as an aluminum evaporation source, and the degree of vacuum was evacuated to 2 × 10 −4 Pa to form an aluminum reflective layer 4 having a thickness of 0.05 μm. As an aluminum evaporation source, an electron beam method may be used in a load lock method, and a carbon crucible may be used. Stable vapor deposition can be continuously performed by appropriately optimizing a durable carbon crucible or the like. In this embodiment, the vacuum deposition apparatus is a self-made machine, but there is no problem even if a commercially available deposition apparatus such as a load lock type deposition apparatus is used. Further, a continuous vapor deposition apparatus capable of vapor deposition on the hoop material may be used. A vacuum deposition apparatus may be selected as appropriate in consideration of film quality, productivity, and the like. Furthermore, the formation method of the aluminum reflective layer 4 may not be a vapor deposition method. That is, an ion plating method, a sputtering method, a cladding method, or the like can be used.

  The film thickness of the aluminum reflective layer 4 was measured by secondary ion mass spectrometry (SIMS) analysis. The thickness from the surface to the point where the main constituent element of the underlayer immediately below the aluminum reflective layer has a signal intensity of ½ of the maximum intensity in the underlayer was defined as the film thickness of the aluminum reflective layer. When the above-mentioned base material 2 is copper, the signal strength of copper is used.

(Evaluation of examples according to the present embodiment)
About the aluminum reflective layer 4, the sulfurization characteristic and the reflectance were confirmed as follows. First, as shown in Table 1, an aluminum reflective layer having a different thickness was produced by the above-described method, and the initial reflectance at a wavelength of 460 nm was measured. At this wavelength, the reflectance of barium sulfate was 100%, the reflectance of 90% or more was particularly good (indicated by ◯), and the reflectance of less than 90% was defective (indicated by x). When aluminum was very thin, that is, when the thickness was 0.01 μm or less, the reflectance was low due to the influence of the reflectance of the underlying metal (here, copper). Next, regarding the sulfuration characteristics, 3 ppm of H2S (hydrogen sulfide) was sprayed for 96 hours at an atmospheric temperature of 40 ° C. and a humidity of 80% for the sample in which the aluminum reflective layer 4 of each thickness was formed (corrosion resistance test of JIS H8502 plating) The test was conducted according to the method). The resistance to sulfuration was defined as the ratio between the initial reflectance and the reflectance after sulfiding for 96 hours. When the aluminum reflective layer was provided, there was nothing that decreased to less than 90% with respect to the initial reflectance. Overall, it has been confirmed that the initial reflectance and sulfurization characteristics (that is, the reflectance after use in an environment that can be sulfided) are good as required characteristics as a substrate for mounting a semiconductor light emitting device. The thickness of the aluminum reflective layer was 0.02 μm or more.

  As Comparative Example 1, when only 3 μm of the silver layer is provided on the base material, the initial reflectance is 93% and good and good, but the sulfurization characteristic is greatly reduced to 29% after the sulfidation resistance test. And it is confirmed that it is not good. In Comparative Example 2, an example in which only a nickel layer (0.7 μm) and a palladium layer (0.05 μm) are provided on a base material has good antisulfurization characteristics, but the initial reflectivity is as low as 63%. Confirm that there is.

  According to the present embodiment, since the aluminum reflective layer is formed on the surface of the base material, a semiconductor light-emitting element mounting substrate having high and stable reflection characteristics over a long period without being sulfided and a semiconductor light-emitting device using the same realizable. This is because the reflectance of aluminum is three times higher than that of silver in ultraviolet rays, and has a reflectance close to silver for purple, red, and infrared rays. It has the next highest reflectivity and utilizes the characteristics that sulfidation does not easily occur compared to silver.

  In order to perform wire bonding on the semiconductor light emitting element mounting substrate described above, argon plasma cleaning is performed, and then a gold wire is bonded. When this semiconductor light emitting element mounting substrate was subjected to a sulfidation test, no reduction in reflectance was observed. From this result, it was found that the resistance to surface cleaning was strong and there was no fear of deterioration or peeling.

  The effects obtained from the first embodiment can also be obtained in the later-described embodiments, although to a different extent.

[Second Embodiment]
FIG. 2 is a schematic cross-sectional view of a semiconductor light-emitting device showing a second embodiment of the present invention, and shows the semiconductor light-emitting device using the semiconductor light-emitting element mounting substrate shown in FIG. In the figure, 2 is a base material, 4 is an aluminum reflective layer formed on one surface of the base material 2, and these constitute a substrate for mounting a semiconductor light emitting element. In the semiconductor light emitting device, two sets (2A and 4A, 2B and 4B) are used in the proximity of substantially the same surface. 6 is a semiconductor light emitting element mounted on the aluminum reflective layer 4A, 7 is a bonding wire for electrically connecting the semiconductor light emitting element 6 and the aluminum reflective layer 4B, 8 is a base 2A excluding the semiconductor light emitting element 6, 2B is made of a resin that surrounds the adjacent side of 2B, and has a concave portion formed by aluminum reflecting layers 4A and 4B located on the bottom surface and the inclined surface that is separated from the semiconductor light emitting element as the distance from the base material increases. An envelope portion 9 is a light-transmitting resin portion that fills the concave portion of the envelope portion 8 and seals the semiconductor light emitting element, and constitutes a part of the envelope. 9 can be mixed with a phosphor material. For example, by mixing yttrium aluminum garnet (YAG) or the like, a 460 nm GaN LED can be used as the LED chip, and a pseudo white LED device can be used.

  The aluminum reflective layer 4 may be formed on the substantially entire inner surface of the envelope, or on the remaining portion excluding a part. This is because the light emitted from the light emitting element only needs to be reflected in the outer enclosure.

  As a specific method, (1) a function of shielding the area other than the envelope region is provided by the film forming apparatus for forming the aluminum reflective layer. (2) After forming the aluminum reflective layer on the entire surface, the envelope portion There are various methods, such as a method of masking the region by taping or photolithography process, and then etching away aluminum, and any of them may be used.

  According to the semiconductor light emitting device having such a configuration, the light emitted from the semiconductor light emitting element 6 is reflected by the aluminum reflective layer 4A, due to the presence of the aluminum reflective layers 4A and 4B located on the bottom surface of the recess formed in the envelope portion 8. 4B reflects to the opening side of the recess, and has the effect of increasing the amount of light from the semiconductor light emitting device. As described above, since aluminum has a good antisulfurization characteristic, a high reflectance can be maintained for a long time.

[Third Embodiment]
FIG. 3 is a schematic cross-sectional view of a substrate for mounting a semiconductor light emitting device showing a third embodiment of the present invention. A nickel layer 17, a palladium layer 18, and a gold flash plating layer 10 are sequentially applied to both surfaces of a base material 2 by a wet plating method. And the aluminum reflecting layer 4 is formed on a part of the gold flash plating layer 10 on one side of the substrate 2. One of the reasons for sequentially forming the nickel layer 17, the palladium layer 18, and the gold flash plating layer 10 on the substrate 2 is to ensure solder wettability between the substrate 2 and the printed wiring board on which the semiconductor light emitting device is mounted. This is to improve solder connectivity. In that case, the thickness of the nickel layer 17 is 0.4 to 1.5 μm, the thickness of the palladium layer 18 is 0.01 to 0.2 μm, and the thickness of the gold flash plating layer 10 is 0.1 μm or less. it can. These thicknesses have been confirmed by the inventor of the present invention, but can be slightly changed depending on the elements to be mounted. The thickness of the aluminum reflective layer 4 is preferably 0.02 μm or more from the viewpoint of light reflection characteristics, and may be about 5 μm, but when dry plating is used, it is preferably 2 μm or less from the viewpoint of flatness (hereinafter the same) ). Here, the gold flash plating layer is not limited to covering the entire surface of the underlayer, but may be formed in spots on the underlayer. For this reason, the reflection characteristic of gold flash plating is a mixture of a gold layer and other underlayers.

  The manufacturing method of the aluminum reflective layer 4 is a vapor deposition apparatus having a pressure reducing function, and is performed by batch processing or continuous processing. The nickel layer and the palladium layer can obtain a plating layer having the quality required for this product, regardless of whether it is a wet plating method or a dry method such as vacuum deposition. In many cases, wet plating can coat the entire surface of the material and can be manufactured at low cost, and it is desirable to form the nickel layer or palladium layer of the present invention by wet plating.

  In addition, the film thickness of the base layer formed by the wet plating method of the nickel layer 17, the palladium layer 18, and the gold flash plating layer 10 was calculated by integrating the current values during plating.

  This nickel layer 17 has a thickness of between 0.5 μm and 1.0 μm for the purpose of preventing discoloration due to copper oxidation of the base material 2 and improving the handling characteristics when the semiconductor light emitting element mounting substrate is hardened. Can take a value. When the element is mounted by soldering, the palladium layer can be provided in order to obtain good solder wettability by forming a palladium layer in a portion serving as a connection portion. The palladium layer is often set to a thickness of 0.03 μm to 0.07 μm, but the thickness is determined by the soldering conditions.

  The effect of this embodiment can ensure a high reflectance by using aluminum as the reflective layer. Furthermore, by using the aluminum reflecting layer 4 having a thickness of 0.02 μm or more, good durability can be obtained, and in addition to the effect that high reflectance can be maintained, the following effects can be obtained. That is, the nickel layer 17 in the above numerical range can prevent the diffusion of copper, which is the main material of the base material 2, and the palladium layer 18 in the above numerical range has wettability with the lead (Pb) -free solder material during mounting. The improvement of the gold flash plating layer 10 within the above-described numerical range provides further effects such as improvement of solder wettability and long-term storage. That is, such a structure can be a structure suitable for soldering.

[Fourth Embodiment]
FIG. 4 is a schematic cross-sectional view of a semiconductor light emitting device showing a fourth embodiment of the present invention. The semiconductor light emitting element mounting substrate shown in FIG. 3, the envelope portion 8 and the light transmitting resin portion 9 shown in FIG. It is an Example of the combined semiconductor light-emitting device. The same parts as those in FIGS. 2 and 3 are denoted by the same reference numerals.

  When using a copper plate as the substrate 2A (2A, 2B), for example, a copper plate having a length of 100 m, a width of 50 mm, and a thickness of 0.2 mm is prepared, and a nickel layer 17 is formed on the surface of the substrates 2A and 2B with a thickness of 1 μm. A palladium layer 18 having a thickness of 0.1 μm and a gold flash plating layer 10 having a thickness of 0.01 μm are sequentially formed by a wet plating method. Furthermore, the aluminum reflective layer 4 (4A, 4B) is left to be used for solder connection on the surface of the gold flash plating layer 10 and is partially deposited on the part used as a reflective film, and the solder connection portion has no aluminum layer. A material having an aluminum layer is obtained in a portion used for reflection. Thereafter, a frame shape for mounting a semiconductor light emitting element is produced by pressing or etching, and two sets (2A and 4A, 2B and 4B) are arranged close to each other on substantially the same plane. Then, a resin envelope portion 8 having a recess that surrounds the adjacent portions of the base materials 2A and 2B and has a perforated portion around the semiconductor light emitting element 6 in advance is formed. Next, the semiconductor light emitting element 6 is mounted with a conductive paste material, and the surface electrode and the lead frame are connected by gold wire bonding. Finally, a light-transmitting resin (silicon resin or the like) is filled in the concave portion of the envelope portion 8 so as to cover the semiconductor light emitting element 6 to form a light-transmitting resin portion 9 that becomes a part of the envelope. To do.

  In the above description, the semiconductor light-emitting element mounting substrate is manufactured and then formed into a predetermined shape using a press or etching, but a post-plating method may be used. That is, after forming the base materials 2A and 2B into a predetermined shape, the aluminum reflective layer 4 is formed on the base material by a wet plating method by a dry plating method such as a vacuum deposition method. It is also possible. Furthermore, as for the base materials 2A and 2B, the case of being made of copper has been described. However, it is possible to use a material in which a copper wiring is provided on a resin or the like. Further, from the viewpoint of use, cost, etc., other metal base materials such as iron-based 42 alloy alloy may be used. Moreover, the aluminum reflective layer 4 (4A, 4B) can be formed and used after forming wiring by a printed wiring board or a flexible wiring board formation process. In this way, depending on the purpose, structure, and material (copper plate or flexible flexible resin substrate), the order of shape production (shape production by punching, bending, overhanging, etc.), plating, and vapor deposition is changed. can do.

  As the semiconductor light emitting element 6 to be mounted, for example, an LED chip such as a GaAs-Si-LED, an AlGaAs-LED, a GaP-LED, an AlGaInP-LED, or an InGaN-LED can be mounted. The semiconductor light emitting device shown in FIG. 4 is a vertical element on the upper and lower electrodes, but is not limited to this, and is a planar LED having a pair of electrodes on the same surface (for example, a GaN-based LED). ). In the case of a planar structure in which the electrodes are formed on the same surface, wire bonding is performed for both the cathode and the anode with the electrode surface facing the upper surface (upper side in the figure), and the electrode surface is lower (lead frame side) Although there is a so-called flip chip mounting method in which direct connection is made toward the substrate, any mounting method can be used. Copper wire bonding or aluminum wire bonding may be used instead of gold wire bonding.

  Furthermore, in this embodiment, the gold flash plating layer 10 is used, but for gold, a relatively rough pitch (for example, 0.5 mm pitch), that is, a case where high precision is not required. Even if the gold flash plating layer 10 is not provided, it is possible to exclude the gold flash plating layer 10 because a high yield is provided. Regarding the palladium layer 18, palladium can be omitted if the thickness of the metal layer is ensured and sufficient solder wettability is obtained.

  According to the semiconductor light emitting device having such a configuration, as in the semiconductor light emitting device shown in FIG. 2, the presence of the aluminum reflecting layers 4A and 4B located on the bottom surface of the recess formed in the envelope portion 8 allows the semiconductor light emitting element. The light emitted from 6 is reflected to the opening side of the recess by the aluminum reflecting layers 4A and 4B, and the light amount from the semiconductor light emitting device is increased. Moreover, since the aluminum reflecting layers 4A and 4B have good light reflection characteristics, a high reflectance can be maintained for a long time. Furthermore, since an intermediate layer composed of the nickel layer 17, the palladium layer 18 and the gold flash plating layer 10 is interposed between the base materials 2A and 2B and the aluminum reflective layers 4A and 4B, Can improve the wettability.

[Fifth Embodiment]
FIG. 5 is a schematic cross-sectional view of a semiconductor light-emitting element mounting substrate showing a fifth embodiment of the present invention. This embodiment is positioned as a modified example of the substrate for mounting a semiconductor light emitting device shown in FIG. 3, and FIG. 5A shows the nickel layer 17, the palladium layer 18, and the gold flash plating layer 10 only on one surface of the substrate 2. FIG. 5B shows an example in which the aluminum reflective layer 4 is formed on a part of the gold flash plating layer 10, and FIG. 5B shows an aluminum layer on a part of the gold flash plating layer 10 formed on one surface of the substrate 2. An example in which the reflective layer 4 is formed and a part of the reflective layer 4 is bent upward by approximately 90 degrees on the paper surface. FIG. 5C shows a nickel layer 17, a palladium layer 18 and a gold flash plating layer 10 formed on the entire surface of the substrate 2. FIG. 5D shows an example in which the aluminum reflective layer 4 is formed on the entire surface of the gold flash plating layer 10 formed, and a part thereof is bent 180 degrees upward on the paper surface. Forming Nickel layer 17 on the other surface of the substrate 2, and an example of forming the palladium layer 18 and the gold flash plating layer 10 shown respectively.

  The substrate for mounting a semiconductor light emitting element shown in FIG. 5A has a nickel layer 17 of 0.4 μm thick by plating on one side of a base material 2 made of copper, and a palladium layer 18 of 0.01 μm thick by plating. The gold flash plating layer 10 has a thickness of 0.1 μm, and the aluminum reflection layer 4 can be formed on a part of the gold flash plating layer 10 by vapor deposition. When nickel, palladium, gold, and aluminum are sequentially laminated on a copper substrate as in this example, a wet plating method can be used except for the aluminum reflective layer. As for the aluminum reflective layer 4, it is preferable to employ a vacuum evaporation method because it cannot be easily plated by a wet plating method at present. As another method, for example, a sputtering method in an inert gas can be used. A plurality of these methods may be used from the viewpoints of cost, simplification of process steps, and the like.

  The substrate for mounting a semiconductor light emitting element shown in FIG. 5B has a nickel layer 17 on the base material 2 having a thickness of 1.5 μm by a plating method, a palladium layer 18 having a thickness of 0.2 μm by a plating method, and a gold flash plating layer 10. Are sequentially formed with a thickness of 0.1 μm, and then an aluminum reflective layer 4 is formed on a part thereof. The semiconductor light emitting element mounting substrate shown in FIG. 5C has a nickel layer 17 applied to the substrate 2 with a thickness of 1.5 μm by plating, a palladium layer 18 with a thickness of 0.2 μm, and a gold flash plating layer 10. Are sequentially formed to a thickness of 0.1 μm, and then an aluminum reflective layer 4 is formed on the entire surface. In these examples, it is assumed that a semiconductor light emitting element is mounted on the upper surface of the aluminum reflective layer 4 and wire bonding is performed on the lower surface or side surface of the base material 2. More specifically, the configuration is applicable when the substrate 2 is bent. In this embodiment, wire bonding is performed on the back surface of the base material 2, but the back surface may be coated with a nickel layer 17, a palladium layer 18, a gold flash plating layer 10 or the like depending on the purpose.

  The substrate for mounting a semiconductor light emitting element shown in FIG. 5D has a nickel layer 17, a palladium layer 18 and a gold flash plating layer 10 applied to only one surface of the substrate 2 as in the example of FIG. Therefore, the amount of these metals used can be suppressed. In the case where only one side is plated, it can be realized without the need for a mask material by laminating two substrates together and flowing them to the plating step and then separating them. As described above, the aluminum reflective layer 4 is likely to be affected by the reflectivity of the base depending on the thickness, and is preferably 0.02 μm or more. Although the aluminum reflective layer 4 is formed on the entire surface, the aluminum reflective layer 4 may be partially formed. After forming the semiconductor light emitting element mounting substrate shown in FIG. 5D, the end portion of the base material (also referred to as a substrate connection lead or outer lead) can be processed into a predetermined shape and used. For example, this configuration can be used when the lower surface of the portion (outer lead) exposed from the envelope of the base material is bent and connected to the base material so as to contact the upper surface of the printed board. That is, the central portion of the base material is used as an aluminum reflecting layer, the lower surface of the end portion of the base material is used as an outer lead, and the nickel-palladium side surface is connected to the printed circuit board.

[Sixth Embodiment]
FIG. 6 is a schematic cross-sectional view of a semiconductor light-emitting element mounting substrate showing a sixth embodiment of the present invention. In this embodiment, palladium (Pd), gold (Au), tin (Sn), nickel (Ni), copper (Cu) -tin (Sn) alloy, copper (Cu)- A single-layer metal layer 11 selected from a nickel (Ni) alloy is formed, and an aluminum reflective layer 4 is formed on the metal layer 11 or the substrate 2. The metal layer 11 is an example of a first metal layer made of a metal other than Ag.

  6A shows an example in which the metal layer 11 is formed on both surfaces of the substrate 2 and the aluminum reflective layer 4 is formed on a part of the metal layer 11 on one surface. FIG. An example in which the metal layer 11 is formed on one surface and the aluminum reflective layer 4 is formed on a part of the metal layer 11, FIG. 6C shows the case where the metal layer 11 is formed on one surface of the substrate 2, The example which formed the aluminum reflective layer 4 in the other direction of the material 2 is each shown. That is, FIGS. 6A to 6C are examples in which the metal layer 11 is exposed on a part of the surface of the semiconductor light emitting element mounting substrate.

  Palladium is more effective in preventing oxidation than copper and has the advantage of being compatible with tin used in soldering. Tin has the advantage of being easy to solder and inexpensive, but has the disadvantage of being easily oxidized. Copper-tin alloys are less susceptible to oxidation than copper and have the advantage of being more familiar with tin than tin and copper. Copper-nickel alloys have the advantage of being more familiar with tin than nickel. Based on these points, an optimum material for the metal layer 11 can be selected depending on the use conditions and the manufacturing conditions.

[Seventh Embodiment]
FIG. 7 is a schematic cross-sectional view of a semiconductor light-emitting element mounting substrate showing a seventh embodiment of the present invention. This embodiment is characterized in that one or a plurality of gold plating layers 12 are formed on the aluminum reflective layer 4. FIG. 7A shows an example in which a gold plating layer 12 is formed on a part of the aluminum reflective layer 4, and FIG. 7B shows a gold plating layer on the gold flash plating layer 10 outside the partially formed aluminum reflective layer 4. 7 (c) shows an example in which the gold plating layer 12 is formed on the entire surface of the aluminum reflective layer 4, FIG. 7 (d) shows a gold flash in which the aluminum reflective layer 4 and the aluminum reflective layer 4 are formed. An example in which the gold plating layer 12 is formed on the entire surface of the plating layer 10 is shown, and FIG. 7E is a schematic cross-sectional view showing an example of an embodiment of a semiconductor light emitting device using this semiconductor light emitting element mounting substrate. Show. In these examples, the nickel layer 17, the palladium layer 18 and the gold flash plating layer 10 are sequentially formed on the entire surface of the substrate 2, but the present invention is not limited thereto. The present invention can also be applied to the case where the single-layer metal layer 11 is formed, or the aluminum reflective layer 4 is directly formed on the substrate 2.

  The gold plating layer 12 in this embodiment can be used for electrical connection of a semiconductor light emitting element mounted on the aluminum reflective layer 4. The thicker the gold plating layer, the lower the reflectance on the short wavelength side (blue) side, but the gold wire connectivity is improved. Depending on the application, the structure of the gold plating layer 12 may be determined in consideration of the reflectance. In addition, although each plating layer (10, 12, 17, 18) was formed by the wet plating method here, you may form by another system.

[Eighth Embodiment]
FIG. 8 is a schematic view showing a typical use state of a semiconductor light emitting device as an eighth embodiment of the present invention. The semiconductor light emitting device according to the present embodiment is used by being mounted on, for example, a printed wiring board using the semiconductor light emitting element mounting substrate 1 according to the first to seventh embodiments. A portion (outer lead) extending outward from the envelope portion 8 of the semiconductor light emitting element mounting substrate 1 to be mounted on the printed wiring board 13 is bent to be substantially flush with the lower surface of the envelope portion 8. 1a or portions 1b and 1c located below the lower surface are formed. This portion is bonded to the wiring of the printed wiring board 13 with solder 14. In FIG. 8A, the outer lead is bent 90 degrees and directed downward, and the outer lead is bent 90 degrees in the opposite direction and directed horizontally, so that the horizontal position of the envelope portion 8 remains unchanged with the outer lead extending in the same direction. FIG. 8B shows an example in which the portion 1a having the substantially same surface as the lower surface is formed. FIG. 8B shows that the outer lead is bent 90 degrees twice along the envelope portion 8 along the lower surface of the envelope portion 8. FIG. 8C shows an example in which the portion 1b is formed. FIG. 8C shows the upper surface of the envelope portion 8 by bending the outer lead 90 degrees twice along the envelope portion 8 in the opposite direction to FIG. 8B. The method of bending the outer lead shown in each of the examples in which the portion 1c is formed along is not limited to this, and a shape suitable for each application in which the semiconductor light emitting device is used is adopted.

[Ninth Embodiment]
The present embodiment is the same as the other embodiments in that an aluminum reflective layer is provided on the substrate as in the first embodiment. However, the carbon concentration of the aluminum reflective layer is 1 × 10 ²⁰ pieces / cm ³ or less.

  In order to evaluate the bondability with the semiconductor light emitting element mounting substrate, a bonding wire made of gold and wire bonding were performed. Here, the wire bonding means that a lead frame side electrode pad and an electrode on an element mounted on the lead frame are connected with a wire such as gold in order to electrically connect them.

  The 1st bonding is to first bond a wire whose tip is made spherical by electric discharge. Usually, the electrode on the element side is often 1st bonding in view of positional accuracy and pressure-bonding properties. In this embodiment, an aluminum reflective layer provided on a copper base material in the same manner as in the first embodiment was bonded to a wire whose tip was made spherical by electric discharge.

  The 2nd bonding means bonding at a predetermined position between the electrode on the element side and the electrode on the lead frame side to be connected with the wire. In the present example, the end of the wire was pressure-bonded in such a manner that it was rubbed onto a copper base material provided with an aluminum reflective layer in the same manner as in the first embodiment.

Table 2 shows the relationship between the carbon concentration in the aluminum reflective layer and the bonding strength between the gold wires. In Example 11, a nickel layer of 0.7 μm and palladium of 0.05 μm formed by a wet plating method on a copper substrate thickness of 0.15 mm was punched and pressed into three layers having a thickness of 0.5 mm. A glass epoxy substrate is fixed with a heat-resistant acrylic resin adhesive, and a circuit board for a light emitting device is formed. This material was attached to the aforementioned vacuum deposition apparatus, an aluminum reflective layer was formed to a thickness of 0.2 μm, and SIMS analysis was performed. Here, the carbon concentration in the aluminum reflecting layer was set to the minimum carbon concentration in the aluminum reflecting layer. The carbon concentration in the aluminum reflective layer was 3 × 10 ²⁰ pieces / cm ³ .

For the base material of Example 12, a polyimide resin film having a thickness of 125 μm and a copper base material of 70 μm, a nickel layer of 0.7 μm, and palladium of 0.05 μm formed by wet plating is bonded with a heat-resistant acrylic resin adhesive. Board material. In Example 12, after forming the aluminum reflective layer, the wiring material was formed by punching and pressing the separation part. When the carbon concentration in the aluminum reflective layer of Example 12 was similarly analyzed, the carbon concentration in the aluminum reflective layer was 1 × 10 ²⁰ pieces / cm ³ .

In Example 13, an iron-coated copper alloy formed by forming a nickel layer of 0.7 μm and palladium of 0.05 μm by a wet plating method, punched and pressed into a vacuum deposition apparatus made of stainless steel (SUS304) The aluminum reflective layer was formed to 0.2 μm. The carbon concentration in the aluminum reflective layer of Example 13 was 3 × 10 ¹⁹ atoms / cm ³ .

  As the evaluation criteria, the first bonding strength was evaluated as “◯” when the shear strength was 0.39 N or more, and “x” when less than 0.39 N. The 2nd bonding strength was evaluated as “◯” when the shear strength was 0.049 N or more, and “x” when less than 0.049 N.

From Table 2, it can be seen that when the carbon concentration of the aluminum reflective layer is 3 × 10 ²⁰ pieces / cm ³ or more, the bonding strength is reduced, and it is preferable to set it to 1 × 10 ²⁰ pieces / cm ³ or less.

  In the present embodiment, the use of an epoxy material increased the carbon concentration, and the bondability was worse than in the other examples. Moreover, although the bondability was within a practical range, the carbon concentration in the aluminum reflective layer also increased when an organic material such as an acrylic adhesive was used. When strongly demanding the bonding property, the resin may be used after forming the substrate for mounting the semiconductor light emitting element, that is, after forming the aluminum reflective layer, without using the resin as in Example 13. Note that various factors such as impurities in the sputtering gas can be considered when the base material is contaminated as a source of carbon contamination into the aluminum reflective layer, the purge gas during sputtering, the reverse diffusion of vacuum pump oil, or the sputtering method.

  For bonding tests, the wire bonder is WEST BOND INC. Model 7700D was used, a gold wire with a diameter of 25 μm was used, the bonding conditions were an ultrasonic intensity of 350 mW, and the ultrasonic wave application time was 100 ms. The test was conducted in the share test mode of the bonding tester PTR-1 of Resuka Co., Ltd. The SIMS measurement was carried out using ADEPT1010 manufactured by PHI and using cesium ions as the primary ion source at an acceleration energy of 3 keV.

  As described above, the inventors have found that the carbon concentration in the aluminum reflecting layer has a great influence on the bonding strength between the gold wire and the aluminum reflecting layer. Note that this applies to all the embodiments described above.

[Tenth embodiment]
FIG. 9 is a schematic cross-sectional view of a semiconductor light emitting device showing a tenth embodiment of the present invention. The feature of this embodiment is that the semiconductor light emitting element 6 is mounted on the aluminum reflective layer 4, and the power supply terminal bases 2B and 2C for wire bonding or inner lead bonding to the semiconductor light emitting element 6 are provided with an aluminum reflective layer. There is no four.

  The aluminum reflective layer 4 may be present at the wire bonding destination, but when the aluminum reflective layer 4 is not present, the range of bonding conditions is expanded by optimizing the surface conditions of the base materials 2B and 2C, and the assembly speed and step It may be better. FIG. 9 shows an example of the same configuration of the base material 2A and the plating layers (10, 17, 18) provided on the base materials 2B, 2C of the mounting portion of the semiconductor light emitting element 6, but the bases of 2A, 2B, 2C are shown. The configuration of the plating layer of the material may be different or may be manufactured separately. FIG. 9 shows the case where the lower portions of the base materials 2A, 2B, and 2C are covered with the resin, but the back surfaces of the base materials 2A, 2B, and 2C may be exposed entirely or partially on the back surface. The exposed material can be further connected to a metal heat radiating plate by soldering or the like, so that the heat dissipation can be improved and the light output can be increased. When the semiconductor light emitting device 6 having the back electrode is used, it is sufficient that one or more power supply terminals are used for connection to the upper electrode, and a plurality of power supply terminals connected to the upper electrode may be wire-bonded. Absent. In the case where a plurality of devices are used, there are cases where the layout of the wiring between the light emitting devices is facilitated when driving with a large current. FIG. 9 shows a case of wire bonding connection between the electrode portion of the light emitting element and the power supply terminal. However, an inner lead made of a patterned wiring material for connection is prepared, and a wedge using ultrasonic waves or heating is used. Connection by bonding may be performed.

  The present invention described in the representative configuration example showing the semiconductor light emitting element mounting substrate of the present invention and the semiconductor light emitting device using the same as an embodiment is not limited to this configuration example. Various configurations are possible within the scope of the technical idea. The main constituent material of the surfaces of the base materials 2B and 2C to be wire-bonded or inner-lead bonded as power supply terminals may be one selected from gold, silver, palladium, gold alloy, silver alloy, or palladium alloy, or a combination thereof. .

(11th to 21st embodiments)
One main basic configuration of a semiconductor light-emitting element mounting substrate and a semiconductor light-emitting device according to a typical embodiment of the present invention is that a silver layer or at least a part of a surface on which a semiconductor light-emitting element is mounted is formed. It is to provide a silver alloy layer and to provide an aluminum reflective layer on the silver layer or the silver alloy layer.

  Another basic configuration of the semiconductor light-emitting element mounting substrate and the semiconductor light-emitting device is to provide a silver layer or a silver alloy layer via a metal layer on at least a part of the surface on which the semiconductor light-emitting element is mounted, An aluminum reflective layer is provided on the silver layer or silver alloy layer via a metal layer.

The thickness of the aluminum reflecting layer is preferably 0.006 μm or more and 2 μm or less, and the impurity carbon concentration of the aluminum reflecting layer is desirably 1 × 10 ¹⁴ atoms / cm ³ or more and 1 × 10 ²⁰ atoms / cm ³ or less. .

  The silver layer or the silver alloy layer is desirably 0.01 μm or more so that light can be reflected even when the aluminum reflective layer is sufficiently thin.

  As the metal layer interposed between the base material and the silver layer or silver alloy layer, for example, one kind selected from palladium, gold, tin, nickel, copper-tin alloy, copper-nickel alloy, iron-nickel alloy or That combination is desirable. As the metal layer interposed between the silver layer or the silver alloy layer and the aluminum reflective layer, for example, gold is preferable, and the thickness is preferably 0.1 μm or less.

  As a material of this base material, for example, a base material made of copper or a copper alloy is desirable from the viewpoint of electrical resistance and thermal resistance. As another material of the base material, for example, an iron-nickel alloy such as 42 alloy, an iron-based frame material, or the like can be used.

  As this base material, what is necessary is just to contain the metal part, for example, the copper-clad board which bonded copper on resin can be used. As this resin, for example, it is formed on the surface opposite to the surface on which the silver layer on the substrate or the silver alloy layer and the aluminum reflecting layer are formed. As the surface of the substrate opposite to the surface on which the aluminum reflective layer is formed, a substrate including a composite structure with an organic material or an inorganic material can be used.

[Eleventh embodiment]
Referring to FIG. 10, reference numeral 1 generally indicates a semiconductor light emitting element mounting substrate according to the eleventh embodiment. The substrate 1 includes a base material 2, a silver layer or silver alloy layer 3 formed on both surfaces of the base material 2, and a semiconductor light emitting element on one surface of the base material 2 via the silver layer or silver alloy layer 3. And the aluminum reflecting layer 4 formed in a region including the place where the metal is mounted.

  This base material 2 is comprised with the composite material of a metal or a metal, and an organic material or an inorganic material. The metal material is not limited, but the most versatile base material is a metal lead frame made of copper or a copper alloy.

  When a copper plate is used as the substrate 2, the thickness is not limited, but the thickness is selected in consideration of cost. In consideration of mass production, a copper plate hoop material is preferable, but a short sheet material or individual material can also be used.

  When using a composite material as this base material 2, the copper clad board with which the copper plate was bonded together on the resin material, or its laminated board can be used. As this resin material, a hard plate-shaped material or a thin flexible material can be used. Typical examples thereof include a glass epoxy substrate (glass cloth base resin plate) and a polyimide resin system.

  The aluminum reflective layer 4 is manufactured by batch processing, continuous processing, or the like using a vapor deposition apparatus having a pressure reduction pressure adjustment function. The thickness of the aluminum reflective layer 4 is preferably 0.006 μm or more from the viewpoint of reflectivity. In addition, 2 μm or less is appropriate from an economic viewpoint.

  Below, the manufacturing method of the board | substrate 1 for semiconductor light-emitting device mounting is demonstrated. In this production, first, a copper plate was prepared as the base material 2. When using a copper plate for the base material 2, the base material 2 has dimensions of, for example, length 100m × width 50mm × thickness 0.2mm, and the thickness of the silver layer is 0.02 μm. The thickness is, for example, 0.05 μm.

  Next, the silver layer or the silver alloy layer 3 was manufactured on both surfaces of the base material 2 by a wet plating method. A silver cyanide plating bath is generally used for silver plating, but a non-cyanide bath may be used. When plating, the glossiness may be improved by adding an organic brightening material or adding a small amount of metal salt (antimony, nickel, cobalt, tin, selenium, etc.). Silver alloy plating can be performed by adding a silver salt to the plating bath and adding a gold plating raw material such as potassium gold cyanide. Similarly, silver alloy plating may be performed by adding a compound salt such as platinum, palladium, rhodium, nickel, or indium to be used for the silver alloy layer.

Next, the aluminum reflective layer 4 was formed on one surface of the silver layer or the silver alloy layer 3 using a resistance heating type / barrel type vacuum deposition apparatus. Specifically, the base material 2 is cut into 16 pieces so as to be a short material of 50 mm × 150 mm, the cut base materials 2 are arranged radially on an umbrella-shaped jig having a radius of 300 mm, and this is arranged in a barrel 3 The base set was arranged. Then, a resistance heating source (output 1 kW) was used as an aluminum deposition source, the degree of vacuum was evacuated to 2 × 10 ⁻⁴ Pa, and the aluminum reflective layer 4 was formed to a thickness of 0.05 μm.

  As an aluminum evaporation source, an electron beam method may be used in a load lock method, and a carbon crucible may be used. Stable vapor deposition can be continuously performed by appropriately optimizing a durable carbon crucible or the like. In the eleventh embodiment, a self-made machine is used as the vacuum vapor deposition apparatus, but a commercially available vapor deposition apparatus such as a load lock type vapor deposition apparatus may be used. Further, a continuous vapor deposition apparatus capable of vapor deposition on the hoop material may be used. A vacuum deposition apparatus may be selected as appropriate in consideration of film quality, productivity, and the like. Furthermore, the formation method of the aluminum reflective layer 4 may not be a vapor deposition method, and for example, an ion plating method, a sputtering method, a cladding method, or the like can be used.

  The thickness of the aluminum reflective layer 4 was measured by SIMS analysis. The thickness from the surface of the aluminum reflecting layer to the point where the main constituent element of the underlayer immediately below the aluminum reflecting layer has a signal intensity that is ½ of the maximum intensity in the underlayer is defined as the film thickness of the aluminum reflecting layer. When the underlayer is silver, the signal intensity of silver is used.

(Evaluation of aluminum reflective layer)
The aluminum reflective layer 4 was compared and evaluated. Table 3 below summarizes the initial reflectivity with respect to the thickness of the aluminum reflective layer 4 and the sulfurization resistance in Examples 21 to 25 and Comparative Examples 21 to 24.

  In confirming these initial reflectivity and anti-sulfurization characteristics, first, the aluminum reflective layer 4 having the thickness changed in seven ways as in Examples 21 to 25 and Comparative Examples 21 and 22 shown in Table 3 below. Was manufactured by the above-described manufacturing method, and the initial reflectance at a wavelength of 460 nm was measured. At this wavelength, the reflectance of barium sulfate was 100%, and the initial reflectance was 70% or more, which was particularly good. On the other hand, an initial reflectance of less than 90% was regarded as defective, and is shown in Table 3 below with a cross.

  As apparent from Table 3 below, when the aluminum reflective layer 4 is very thin, that is, the thickness of the aluminum reflective layer 4 is less than 0.006 μm, those of Comparative Examples 21 and 22 have the reflectance of the metal of the underlayer. (In this case, silver) was affected, and the initial reflectance was good.

In this resistance to sulfuration, 3 ppm of H ₂ S (hydrogen sulfide) was applied to a sample in which the aluminum reflective layer 4 having the thicknesses of Examples 21 to 25 shown in Table 3 below was formed. (The test based on the JIS H8502 plating corrosion resistance test method was conducted) for 96 hours. This anti-sulfurization characteristic was expressed as the ratio between the initial reflectivity and the initial reflectivity after sulfiding for 96 hours in Table 3 below.

  As is apparent from Table 3 below, those of Examples 21 to 25 in which the thickness of the aluminum reflective layer 4 is 0.006 μm or more obtained a high sulfuration resistance of 80% or more with respect to the initial reflectance. .

  In Table 3 below, in place of the aluminum reflective layer 4, the comparative example 23 in which only the silver layer was provided on the substrate 2 had a good initial reflectance of 93%. The reflectance after the sulfidation test was greatly reduced to 29%, and the initial reflectance and the sulfidation resistance were not compatible. On the other hand, the comparative example 24 in which the nickel layer (0.7 μm) and the palladium layer (0.05 μm) are provided on the substrate 2 has good anti-sulfurization characteristics, but the initial reflectivity is as low as 63%. Thus, as in Comparative Example 23, it was found that the initial reflectivity and the antisulfurization characteristic are not compatible.

  From these results, as a characteristic required for the substrate 1 for mounting the semiconductor light emitting device, both the initial reflectance and the anti-sulfurization characteristic (that is, the reflectance after use in an environment that can be sulfurized) are good. It was confirmed that the thickness of the aluminum reflective layer 4 was 0.006 μm or more. It is possible to achieve both initial reflectivity and sulfuration resistance. Preferably, it is desirable to satisfy the condition that the initial reflectance is 90% or more and the sulfuration resistance is 80% or more.

  In order to perform wire bonding on the substrate 1, argon plasma cleaning was performed, and then a gold wire was bonded, and a sulfuration test was performed on the substrate 1 having a thickness of 0.006 μm or more of the aluminum reflective layer 4. There was almost no drop in the. From this result, it was found that the resistance to surface cleaning was strong and there was no fear of deterioration or peeling.

(Effect of 11th Embodiment)
According to the eleventh embodiment, since the aluminum reflective layer 4 is formed on the surface of the base material 2 via the silver layer or the silver alloy layer 3, it is high for a long period without being sulfided, and A substrate for mounting a semiconductor light emitting element having stable reflection characteristics and a semiconductor light emitting device using the same can be realized. This is because the reflectivity of aluminum is three times higher than that of silver in the ultraviolet region, and it has a reflectivity close to silver for purple, red, and infrared rays. This is because it has the second highest reflectivity and is less susceptible to sulfidation than silver.

  The effects obtained from the eleventh embodiment can also be obtained in the following embodiments. The twelfth to twenty-first embodiments will be specifically described below with reference to FIGS. 11 to 19 and Table 4.

[Twelfth embodiment]
Referring to FIG. 11, a semiconductor light emitting device according to the twelfth embodiment is schematically shown in FIG. In the figure, reference numeral 5 generally indicates a semiconductor light emitting device using the substrate 1 for mounting a semiconductor light emitting element shown in FIG. The semiconductor light emitting device 5 according to the illustrated example uses the substrate 1 shown in FIG. 10 as a pair of metal lead frames. The pair of substrates 1 are mainly composed of a base material 2, a silver layer or silver alloy layer 3, and an aluminum reflecting layer 4, and are arranged close to each other on substantially the same plane.

  Among these substrates 1, a semiconductor light emitting element (LED chip) 6 is mounted on the aluminum reflective layer 4 of one substrate 1 as shown in FIG. 11. On the aluminum reflective layer 4 of the other substrate 1, a bonding wire 7 connected to the semiconductor light emitting element 6 is joined and disposed.

  As shown in FIG. 11, the semiconductor light emitting device 5 surrounds a portion where the side surfaces of the pair of base materials 2 and 2 are close to each other except for the pair of aluminum reflecting layers 4 and 4 and the semiconductor light emitting element 6. A resin envelope portion 8 is formed. The envelope portion 8 has a concave portion 8a opened by an inclined surface 8b formed in a divergent shape in a direction away from the base material 2. The concave portion 8a is filled with a light transmissive resin for sealing the semiconductor light emitting element 6, and a light transmissive resin portion 9 is formed. The light transmissive resin portion 9 constitutes a part of the envelope portion 8. By mixing a phosphor material such as YAG in the light transmissive resin portion 9, the semiconductor light emitting element 6 can be used as a pseudo white LED device composed of a 460 nm GaN LED.

  The envelope portion 8 has a concave portion 8a having an inclined surface 8b formed in a divergent shape in a direction away from the base material 2, but is not limited to the illustrated example, for example, the inclined surface 8b. It may replace with and may be a recessed part formed with the perpendicular surface which stands with respect to the base material 2. FIG. Moreover, the aluminum reflective layer 4 should just be formed in the remaining part except the substantially whole surface inside the envelope part 8, or one part. The reason is that the light emitted from the semiconductor light emitting element 6 only needs to be reflected in the envelope portion 8.

Specific methods for forming the aluminum reflective layer 4 include the following various methods, and any of them may be used.
(1) A method of providing a function of shielding areas other than the region of the envelope portion 8 by a film forming apparatus when forming the aluminum reflective layer 4.
(2) A method in which after the aluminum reflective layer 4 is formed on the entire surface of the substrate 2, the region of the envelope portion 8 is masked by taping or photolithography process, and then the aluminum is removed by etching.

(Effect of 12th Embodiment)
According to the semiconductor light emitting device 5 having such a configuration, the light emitted from the semiconductor light emitting element 6 is reflected by the aluminum reflective layers 4, 4 due to the presence of the aluminum reflective layers 4, 4 located on the bottom surface of the recess 8 a of the envelope portion 8. Is reflected on the opening side of the concave portion 8a, and the light amount from the semiconductor light emitting element 6 is increased. As described above, the aluminum reflective layer 4 has a good antisulfurization characteristic, and thus can maintain a high reflectance for a long time.

[Thirteenth embodiment]
FIG. 12 schematically shows a substrate for mounting a semiconductor light emitting element according to a thirteenth embodiment. In the figure, the difference from the eleventh embodiment is a substrate 1 in which an aluminum reflective layer 4 is formed on a silver layer or a silver alloy layer 3 via a gold flash plating layer 10. In the illustrated example, the substrate 1 is formed by sequentially forming silver layers or silver alloy layers 3 and 3 and gold flash plating layers 10 and 10 on both sides of the base material 2 by a wet plating method. An aluminum reflecting layer 4 is formed on a part of the gold flash plating layer 10 on the side.

  One of the reasons for sequentially forming the silver layer or silver alloy layers 3 and 3 and the gold flash plating layers 10 and 10 on both surfaces of the base material 2 is the soldering between the base material 2 and the printed wiring board on which the semiconductor light emitting device is mounted. This is to ensure wettability, that is, to improve solderability. The thickness of the silver layer or the silver alloy layer 3 can be set to 1.0 to 5 μm, and the thickness of the gold flash plating layer 10 can be set to 0.1 μm or less. Is preferred. The thickness of the aluminum reflective layer 4 is preferably 0.006 μm or more and 2 μm or less from the viewpoint of resistance to sulfuration.

  The aluminum reflective layer 4 is produced by a vapor deposition apparatus having a decompression function by batch processing or continuous processing. The silver layer or the silver alloy layer 3 can obtain a plating layer having a quality required for a semiconductor light emitting device, regardless of whether it is a wet plating method or a dry method such as vacuum deposition. In many cases, wet plating can be applied to the entire surface of the material and can be manufactured at low cost, and the silver layer or silver alloy layer 3 is preferably formed by wet plating.

  In addition, the film thickness of the foundation layer formed into a film by the wet plating method of the silver layer or the silver alloy layer 3, and the gold flash plating layer 10 was calculated by integrating | accumulating the electric current value at the time of plating.

(Effect of 13th Embodiment)
According to the thirteenth embodiment, good sulfidation resistance can be ensured by using aluminum as the reflective layer. Furthermore, by using the aluminum reflective layer 4 having a thickness of 0.006 μm or more, good durability can be obtained, and in addition to the effect that high reflectance can be maintained, the following effects can be obtained.

  That is, the silver layer or silver alloy layer 3 in the above numerical range can prevent the diffusion of copper, which is the main material of the substrate 2, and the gold flash plating layer 10 in the above numerical range has solder wettability. There are new effects such as enabling improvement and long-term storage. With the substrate structure as in the thirteenth embodiment, the substrate 1 suitable for soldering can be obtained effectively.

[Fourteenth embodiment]
Referring to FIG. 13, FIG. 13 schematically shows a semiconductor light emitting device 5 according to a fourteenth embodiment using the substrate 1 shown in FIG. This semiconductor light emitting device 5 also has the envelope portion 8 and the light transmissive resin portion 9 in the twelfth embodiment shown in FIG.

  In manufacturing the semiconductor light-emitting device 5, when using a copper plate as the base material 2, for example, a long copper plate of length 100m × width 50mm × thickness 0.2mm is prepared, and a silver layer is formed on the surface of the base 2 Alternatively, the silver alloy layer 3 is formed to a thickness of 3 μm, and the gold flash plating layer 10 is sequentially formed to a thickness of 0.01 μm by a wet plating method. Further, the aluminum reflective layer 4 is partially deposited on the portion used as the reflective film, leaving the portion used for solder connection on the gold flash plating layer 10. As a result, a material is obtained in which there is no aluminum in the solder connection portion of the gold flash plating layer 10 and the aluminum reflection layer 4 is present in the portion used for reflection of the gold flash plating layer 10. Then, the base material 2 is produced in a frame shape for mounting a semiconductor light emitting element by pressing or etching.

  Next, the pair of substrates 1 and 1 are arranged close to each other on substantially the same plane. A resin envelope portion 8 having a concave portion 8a surrounding the semiconductor light emitting element 6 and surrounding the adjacent portions of the pair of base materials 2 and 2 is formed. Next, the semiconductor light emitting element 6 is mounted on the aluminum reflective layer 4 with a conductive paste material, and the surface electrode of the semiconductor light emitting element 6 and the lead frame (substrate 1) are connected by a bonding wire 7 made of gold. Finally, a light-transmitting resin part that becomes a part of the envelope part 8 by filling a light-transmitting resin (silicon resin or the like) so as to cover the semiconductor light emitting element 6 in the recess 8 a of the envelope part 8. 9 is formed.

  In the fourteenth embodiment, an example of forming the substrate 1 and then forming it into a predetermined shape using a press or etching has been described. However, a post-plating method may be used. That is, after the base material 2 is formed into a predetermined shape, the aluminum layer is reflected on the base material 2 by a wet plating method and each of the silver layer or silver alloy layer 3 and the gold flash plating layer 10 by a dry plating method such as a vacuum deposition method. It is also possible to form the layer 4. Furthermore, although the case where the base material 2 is made of copper has been described, a material in which a copper wiring is provided on a resin or the like can be used. Further, from the viewpoint of use, cost, etc., other metal base materials such as iron-based 42 alloy alloy may be used. Moreover, the aluminum reflective layer 4 can be formed and used after forming wiring by a printed wiring board or a flexible wiring board formation process. In this way, depending on the purpose, structure, and material (copper plate or flexible flexible resin base material), the order of shape production (shape production by punching, bending, overhanging, etc.), plating, and vapor deposition is changed. can do.

  As the semiconductor light emitting element 6 to be mounted, LED chips such as GaAs-Si-LED, AlGaAs-LED, GaP-LED, AlGaInP-LED, and InGaN-LED can be mounted. The semiconductor light emitting element 6 shown in FIG. 13 is exemplified by a vertical element in which upper and lower electrodes are formed. However, the present invention is not limited to this, and a planar LED having a pair of electrodes on the same surface. (For example, GaN-based) may be used. In the case of a planar structure in which the electrodes are formed on the same surface, both the cathode and the anode are subjected to wire bonding with the electrode surface facing the surface side (upper side in FIG. 13), and the electrode surface is directed downward (lead frame). There is a so-called flip-chip mounting method in which direct connection is made to the side, but any mounting method can be used. Instead of gold wire bonding, copper-based wire bonding or wire bonding made of aluminum may be used.

  Further, in the fourteenth embodiment, the one provided with the gold flash plating layer 10 is used. However, with respect to gold, a relatively rough pitch (for example, in the case of 0.5 mm pitch), that is, a high precision is required. If there is no gold flash plating layer 10, a high yield can be obtained without the gold flash plating layer 10, so that the gold flash plating layer 10 can be excluded.

(Effect of 14th Embodiment)
According to the semiconductor light emitting device 5 having such a configuration, the presence of the pair of aluminum reflecting layers 4 and 4 located on the bottom surface of the recess 8a formed in the envelope portion 8 is the same as that of the semiconductor light emitting device 5 shown in FIG. In addition, the light emitted from the semiconductor light emitting element 6 is reflected to the opening side of the recess 8 a by the pair of aluminum reflecting layers 4, 4, and the light amount from the semiconductor light emitting device 5 is increased. Moreover, since the aluminum reflective layer 4 has a favorable sulfurization resistance, a high reflectance can be maintained for a long time. Further, since an intermediate layer composed of a silver layer or a silver alloy layer 3 and a gold flash plating layer 10 is interposed between the base material 2 and the aluminum reflective layer 4, wettability with a Pb-free solder material at the time of mounting. Can be improved.

[Fifteenth embodiment]
FIG. 14 schematically shows a semiconductor light emitting element mounting substrate according to the fifteenth embodiment. The fifteenth embodiment is a modification of the substrate 1 according to the thirteenth embodiment shown in FIG. 12, and there is no difference in the basic configuration from the substrate 1 according to the thirteenth embodiment. .

  A significant difference from the thirteenth embodiment is that a silver layer or a silver alloy layer 3 and a gold flash plating layer 10 are sequentially formed on one surface of the substrate 2 as shown in FIG. In the configuration example in which the aluminum reflective layer 4 is formed on a part of the flash plating layer 10, as shown in FIG. 14B, one side end portion of the substrate 1 is bent approximately 90 degrees to the gold flash plating layer 10 side. There is a configuration example.

  As another structural example that is significantly different from the thirteenth embodiment, as shown in FIG. 14C, a silver layer or a silver alloy layer 3 and a gold flash plating layer 10 are formed on the entire surface of the substrate 2. The aluminum reflective layer 4 is formed on the entire surface of the gold flash plating layer 10 and one end portion of the substrate 1 is bent 180 degrees toward the gold flash plating layer 10 side, as shown in FIG. Further, the aluminum reflective layer 4 is directly formed on one surface of the substrate 2, and the silver layer or the silver alloy layer 3 and the gold flash plating layer 10 are formed on the other surface of the substrate 2.

  In the substrate 1 shown in FIG. 14A, a silver layer or a silver alloy layer 3 is formed on one side of a base 2 made of copper by a plating method to a thickness of 3 μm, and a gold flash plating layer 10 is sequentially formed to a thickness of 0.1 μm. After that, the aluminum reflective layer 4 is formed on the partial upper surface of the gold flash plating layer 10 by vapor deposition. When silver or a silver alloy, gold, and aluminum are sequentially laminated on the copper substrate 2 as in this configuration example, a wet plating method can be used except for the aluminum reflective layer 4. The aluminum reflective layer 4 is currently not easily plated by a wet plating method, so a vacuum deposition method may be employed. As another method, for example, a sputtering method in an inert gas can be used. A plurality of these methods may be used from the viewpoints of cost, simplification of process steps, and the like.

  A substrate 1 shown in FIG. 14B is formed by sequentially forming a silver layer or a silver alloy layer 3 on a base material 2 to a thickness of 2 μm by plating and a gold flash plating layer 10 to a thickness of 0.1 μm, followed by a gold flash. An aluminum reflective layer 4 is formed on a part of the surface of the plating layer 10 and configured. A substrate 1 shown in FIG. 14C is formed by sequentially forming a silver layer or a silver alloy layer 3 on a base material 2 to a thickness of 1.5 μm by plating and a gold flash plating layer 10 to a thickness of 0.1 μm. An aluminum reflective layer 4 is formed on the entire surface of the gold flash plating layer 10.

  The configuration example shown in FIGS. 14B and 14C assumes a usage in which the semiconductor light emitting element 6 is mounted on the upper surface of the aluminum reflective layer 4 and wire bonding is performed on the lower surface or side surface of the base material 2. More specifically, the configuration is applicable when the substrate 2 is bent. In the fifteenth embodiment, wire bonding is performed on the back surface of the substrate 2, but the back surface may be coated with a silver layer or a silver alloy layer 3, a gold flash plating layer 10 or the like depending on the purpose. I do not care.

  A substrate 1 shown in FIG. 14 (d) has a silver layer or a silver alloy layer 3 and a gold flash plating layer 10 applied to only one surface of the substrate 2. Therefore, the usage amount of these metals can be suppressed. In the case where only one surface of the base material 2 is plated, the two base materials 2 and 2 are bonded to each other and flowed to the plating step, and then separated without any need for a mask material. As described above, the aluminum reflective layer 4 is likely to be affected by the reflectance of the base layer depending on the thickness, and is preferably 0.006 μm or more and 2 μm or less. Although the aluminum reflective layer 4 is directly formed on the entire surface of the substrate 2, the aluminum reflective layer 4 may be partially directly formed on the surface of the substrate 2.

(Effect of 15th Embodiment)
Even in the fifteenth embodiment, the same effect as in the thirteenth embodiment can be obtained. In addition, after the substrate 1 according to the illustrated example is formed, the end portions (also referred to as substrate connection leads and outer leads) can be processed into a predetermined shape and used. As an example, it can be used when the lower surface of the portion (outer lead) exposed from the envelope portion 8 of the substrate 1 is bent so as to be in contact with the upper surface of the printed wiring board and connected to the substrate 1. . That is, the central portion of the substrate 1 is used as the aluminum reflecting layer 4, the lower surface of the end portion of the substrate 1 is used as an outer lead, and the surface on the gold flash plating layer 10 side is connected to the printed wiring board.

[Sixteenth embodiment]
Referring to FIG. 15, FIG. 15 schematically shows a semiconductor light emitting element mounting substrate according to the sixteenth embodiment. In the same figure, the difference from the above embodiments is that palladium (Pd), gold (Au), tin (Sn), nickel (Ni), copper (Cu)- A metal layer 11 selected from a tin (Sn) alloy and a copper (Cu) -nickel (Ni) alloy is formed, and a silver layer or a silver alloy layer 3 is formed on the metal layer 11 or the base material 2. The aluminum reflective layer 4 is formed on the silver layer or the silver alloy layer 3.

  As a configuration example of the substrate 1, as shown in FIG. 15A, the metal layer 11 is formed on both surfaces of the base material 2, and the silver layer or the silver alloy layer 3 is formed on the entire surface of the metal layer 11 on one surface. However, there is a configuration example in which the aluminum reflective layer 4 is formed on a part of the surface of the silver layer or the silver alloy layer 3, and the metal layer 11 is formed on one surface of the substrate 2 as shown in FIG. There is a configuration example in which a silver layer or silver alloy layer 3 is formed on the entire surface of the metal layer 11 and an aluminum reflective layer 4 is formed on a part of the surface of the silver layer or silver alloy layer 3. As another configuration example of the substrate 1, as shown in FIG. 15C, a metal layer 11 is formed on one surface of the substrate 2, and a silver layer or a silver alloy layer 3 is formed on the other surface of the substrate 2. There is a configuration example in which the aluminum reflective layer 4 is formed on the entire surface of the silver layer or the silver alloy layer 3.

(Effect of 16th Embodiment)
Even in the sixteenth embodiment, the same effect as in the eleventh embodiment can be obtained. Palladium, which is a constituent component of the metal layer 11, has an antioxidant effect than copper and has the advantage of being compatible with tin used for solder. On the other hand, although tin is easily oxidized, it has the advantage of being easy to solder and inexpensive. Nickel that is a constituent component of the metal layer 11 has an effect of suppressing the diffusion of copper and an advantage that the hardness is increased. The copper-tin alloy that is a constituent component of the metal layer 11 is less likely to be oxidized than copper. Compared to tin, it has the advantage of being familiar with tin. The copper-nickel alloy, which is a constituent component of the metal layer 11, has an advantage that it can be easily combined with tin than nickel. Based on these points, an optimum material for the metal layer 11 can be selected depending on the use conditions and the manufacturing conditions.

[Seventeenth embodiment]
FIG. 16 schematically shows a substrate for mounting a semiconductor light emitting element according to a seventeenth embodiment. Even in the seventeenth embodiment, the substrate 2, the silver or silver alloy layer 3, the aluminum reflecting layer 4, and the gold flash plating layer 10 according to the thirteenth and fourteenth embodiments are basically the same. There is no change in the configuration. In the illustrated example, the basic configuration of the substrate 1 is that the gold plating layer 12 is formed on the aluminum reflective layer 4 or the gold flash plating layer 10 at one place or a plurality of places.

  As an example of this substrate 1, there is a configuration example in which a gold plating layer 12 is formed on a part of the surface of the aluminum reflective layer 4 as shown in FIG. 16A, and as shown in FIG. There is a configuration example in which a gold plating layer 12 is formed on the same surface as the aluminum reflective layer 4 partially formed on a partial surface of the gold flash plating layer 10.

  As an example of the substrate 1, as shown in FIG. 16C, a configuration example in which a gold plating layer 12 is formed on the entire surface of the aluminum reflective layer 4 partially formed on a part of the surface of the gold flash plating layer 10. As shown in FIG. 16D, there is a configuration example in which the gold plating layer 12 is formed on the entire surface of the gold flash plating layer 10 and the aluminum reflective layer 4 partially formed on a part of the surface of the gold flash plating layer 10. .

(Effect of 17th Embodiment)
Even in the seventeenth embodiment, the same effect as in the eleventh embodiment can be obtained.

[Eighteenth embodiment]
Referring to FIG. 17, FIG. 17 schematically shows an example of a semiconductor light emitting device using the substrate 1 shown in FIG. 16A among the semiconductor light emitting element mounting substrate 1 according to the seventh embodiment. Is shown in Also in the semiconductor light emitting device 5 shown in FIG. 17, the pair of substrates 1 and 1 are arranged close to each other on substantially the same plane. A bonding wire 7 that is electrically connected to the semiconductor light emitting element 6 is bonded to the gold plating layer 12. The remaining configuration is not different from the above embodiments.

  In the seventeenth and eighteenth embodiments, the silver layer or silver alloy layer 3 and the gold flash plating layer 10 are sequentially formed on the entire surface of the substrate 2, but the present invention is not limited to this. As described in each of the above-described embodiments, the present invention can be applied to the case where the single-layer metal layer 11 is formed, and the case where the aluminum reflective layer 4 is directly formed on the substrate 2.

(Effect of 18th Embodiment)
Even in the eighteenth embodiment, the same effect as in the eleventh embodiment can be obtained. The gold plating layer 12 in the seventeenth and eighteenth embodiments can be used for electrical connection of the semiconductor light emitting element 6 mounted on the aluminum reflective layer 4. In the substrate configurations shown in FIGS. 16C and 16D, the thicker the gold plating layer 12, the lower the reflectance on the short wavelength side (blue) side, but the better the connectivity of the gold wire. Depending on the application, the structure of the gold plating layer 12 may be determined in consideration of the reflectance. In addition, although each plating layer (3, 10, 12) was formed by the wet plating method here, you may form by another system.

[Nineteenth embodiment]
Referring to FIG. 18, FIG. 18 shows a typical usage state of the semiconductor light emitting device according to the nineteenth embodiment. The semiconductor light emitting device 5 is a semiconductor light emitting device using the semiconductor light emitting element mounting substrate 1 according to the eleventh to eighteenth embodiments, and is used by being mounted on a printed wiring board 13, for example. In order to mount on the printed wiring board 13, the board 1 has a first portion in which a portion (outer lead) 20 extending linearly from the side surface of the envelope portion 8 toward the outside is bent to the printed wiring board 13 side. A bent portion 21 and a second bent portion 22 that is bent horizontally with respect to the printed wiring board 13 are provided. The second bent portion 22 is a portion that is substantially flush with the lower surface of the envelope portion 8, a portion that is located below the lower surface of the envelope portion 8, or that is located above the upper surface of the envelope portion 8. Is forming. The second bent portion 22 is bonded to the wiring 15 of the printed wiring board 13 with the solder 14. The outer lead 20 is a part of the semiconductor light emitting element mounting substrate 1.

  The outer lead 20 includes each plating layer (3, 10, 12). As an example of the outer lead 20, as shown in FIG. 18A, a first portion in which an intermediate portion of the outer lead 20 is bent at approximately 90 degrees on the side opposite to the opening side of the concave portion 8 a of the envelope portion 8. And the second bent portion 22 of the outer lead 20. The second bent portion 22 of the outer lead 20 has a second bent portion 22 bent at about 90 degrees in the horizontal direction away from the envelope portion 8. There is a configuration example in which is bent in substantially the same plane as the bottom surface on the bottom surface side of the concave portion 8a of the envelope portion 8.

  As another example of the outer lead 20, as shown in FIG. 18B, the second bent portion 22 is folded along the lower surface opposite to the opening side of the concave portion 8a of the envelope portion 8. As shown in FIG. 18C, there is a configuration example in which the middle portion of the outer lead 20 is bent at approximately 90 degrees in the same direction as the opening side of the concave portion 8a of the envelope portion 8 as shown in FIG. The outer lead includes an outer lead having a bent portion 21 and a second bent portion 22 bent at approximately 90 degrees in the horizontal direction approaching the envelope portion 8, and the second bent portion 22 of the outer lead 20. Is bent along the upper surface on the opening side of the recess 8a of the envelope portion 8. In the configuration example shown in FIG. 18C, a light transmitting hole is formed in the printed wiring board 13 to extract light to the printed wiring board 13 side, or a light transmissive material such as glass or transparent resin is applied to the printed wiring board 13. Used when extracting light to the printed wiring board 13 side.

(Effects of the nineteenth embodiment)
Even in the nineteenth embodiment, in addition to obtaining the same effect as in the eleventh embodiment, the bent form of the outer lead 20 is limited to the illustrated example. In addition, various shapes suitable for each application in which the semiconductor light emitting device 5 is used can be employed.

[20th embodiment]
In the twentieth embodiment, there is no difference from the eleventh embodiment shown in FIG. 10 in that the aluminum reflecting layer 4 is provided on the substrate 2 via the silver layer or the silver alloy layer 3. . The configuration of the substrate 1 according to the ^twentieth embodiment is different from that of the first embodiment in that the carbon concentration of the aluminum reflecting layer 4 is set to 1 × 10 ²⁰ pieces / cm ³ or less. .

  In order to evaluate bondability with the substrate 1 according to the twentieth embodiment, a bonding wire made of gold and wire bonding were performed. Here, the wire bonding refers to connecting with a wire such as gold in order to electrically connect the electrode pad on the lead frame side and the electrode on the element mounted on the lead frame. In general, wire bonding is generally used as an electrical connection method in a mounting technique between a semiconductor element and a lead frame material as in this case, and in recent years, flip-chip ball bump connection or the like is also performed in some element mounting techniques. However, connection by bonding with metal wires such as gold, silver, copper, and aluminum is performed.

  The 1st bonding is to first bond a wire whose tip is made spherical by a discharge (wire ball). Usually, the electrode on the element side is often set to 1st bonding in consideration of positional accuracy and pressure-bonding property. In the twentieth embodiment, WEST BOND INC. Is attached to the wire bonder. Model 7700D was used, and a gold bonding wire having a diameter of 25 μm was used. As bonding conditions, the wire ball diameter was 70 μm, the weight was 100 g, the ultrasonic intensity was 350 mW, and the ultrasonic wave application time was 100 ms. Similar to the eleventh embodiment, the aluminum reflecting layer 4 provided on the copper substrate was bonded with a wire whose tip was made spherical by discharge.

  The 2nd bonding refers to performing stitch bonding to the electrode on the lead frame side to be connected with the wire after performing first bonding on the electrode on the element side. Stitch bonding means that the wire shape cannot be processed, such as ball formation, in a state where the wires are connected, so that the substrate is pressed and tensile cut as it is. Wire connection is completed by performing 1st bonding and 2nd bonding continuously. In the tenth embodiment, as in the eleventh embodiment, the tip of the wire was crimped in such a manner that it was rubbed against a copper substrate 1 provided with an aluminum reflective layer 4.

  Table 4 below shows the relationship between the carbon concentration in the aluminum reflective layer 4 and the bonding strength between the bonding wire 7 made of gold.

In Example 26 shown in Table 4 below, a substrate 2 made of copper having a thickness of 70 μm and a silver layer or a silver alloy layer 3 having a thickness of 2 μm were formed on the entire surface of a polyimide resin film having a thickness of 125 μm by a wet plating method. Is a plate material bonded with a heat-resistant acrylic resin adhesive. After the aluminum reflective layer 4 is formed, the wiring material is formed by punching and pressing the separation portion. When the carbon concentration in the aluminum reflective layer 4 of Example 6 was analyzed by SIMS, the carbon concentration in the aluminum reflective layer 4 was 1 × 10 ²⁰ pieces / cm ³ .

In Example 27 shown in Table 4 below, a silver layer or silver alloy layer 3 having a thickness of 3 μm formed on an iron-containing copper alloy by a wet plating method and punched and pressed is made of stainless steel ( The aluminum reflective layer 4 having a thickness of 0.2 μm was formed by fixing with a SUS304) jig. The carbon concentration in the aluminum reflective layer 4 of Example 27 was 3 × 10 ¹⁹ atoms / cm ³ .

In Example 28 shown in Table 4 below, a material obtained by forming a silver layer or silver alloy layer 3 having a thickness of 3 μm on a copper base material having a thickness of 0.15 mm by a wet plating method is punched and pressed. A circuit board for a light emitting device is formed by fixing with a heat-resistant acrylic resin adhesive on a three-layer glass epoxy substrate having a thickness of 0.5 mm. This base material was attached to the above-described vacuum vapor deposition apparatus, an aluminum reflective layer 4 was formed to a thickness of 0.2 μm, and SIMS analysis was performed. Here, the carbon concentration in the aluminum reflective layer 4 was set to the minimum carbon concentration in the aluminum reflective layer 4. As a result, the carbon concentration in the aluminum reflective layer 4 was 3 × 10 ²⁰ pieces / cm ³ .

As the evaluation criteria, the 1st bonding strength is good when it has a shear strength of 0.39 N or more, and is indicated by a circle in Table 4 below. A case having a shear strength of less than 0.39 N was regarded as defective, and is indicated by a cross in Table 4 below. The 2nd bonding strength is good when it has a shear strength of 0.049 N or more, and is indicated by a circle in Table 4 below. When the shear strength was less than 0.049N, it was judged as defective, and is shown by x in Table 4 below.
In the above embodiment, the shear test has been performed in order to separate and measure the strengths of the 1st and 2nd bonding strengths. However, it takes time and labor to evaluate the wire connection strength in the shear test. In general, a pull test is often used to evaluate the wire connection strength. In the pull test, the strength between the connected gold wires cannot be measured by evaluating the load, the break position, and the shape of the wire between 1st and 2nd. This time, we conducted the following pull test using Dege Bond Tester Series 4000.

As is apparent from Table 4, in Example 28 in which the carbon concentration of the aluminum reflective layer 4 is 3 × 10 ²⁰ pieces / cm ³ or more, the bonding strength is reduced. It can be seen that if the carbon concentration of the layer 4 is 1 × 10 ²⁰ pieces / cm ³ or less, the bonding strength is good.

  In the twentieth embodiment, the carbon concentration in the aluminum reflective layer 4 is increased by using an organic material such as an epoxy material or an acrylic adhesive. This may be due to various factors such as contamination of the base material 2 as a carbon contamination source, purge gas, back diffusion of vacuum pump oil, and sputtering gas impurities.

  In addition, the wire bonder in the bonding test is WEST BOND INC. Model 7700D was used, and a gold bonding wire having a diameter of 25 μm was used. The bonding conditions were an ultrasonic intensity of 350 mW and an ultrasonic wave application time of 100 ms. The test was performed in a share test mode of a bonding tester PTR-1 manufactured by Reska Co., Ltd. The SIMS measurement was carried out using ADEPT 1010 manufactured by PHI and using cesium ions as a primary ion source at an acceleration energy of 3 keV.

(Effect of 20th Embodiment)
According to the twentieth embodiment, by setting the carbon concentration of the aluminum reflecting layer 4 to 1 × 10 ²⁰ pieces / cm ³ or less, in addition to the effects of the eleventh embodiment, the bonding property is improved. An excellent substrate for mounting a semiconductor light emitting element and a semiconductor light emitting device using the same are obtained.

[Twenty-first embodiment]
Referring to FIG. 19, FIG. 19 schematically shows a semiconductor light emitting element mounting substrate and a semiconductor light emitting device according to a twenty-first embodiment. In the figure, the basic configuration in the twenty-first embodiment is that the semiconductor light emitting element 6 is mounted on an independent base material 2A and is not mounted on the base materials 2B and 2C used for energization. This is greatly different from the above embodiments. In the illustrated example, the power supply terminal base material 2B for bonding wiring with a wiring material called a so-called inner lead using a semiconductor light emitting element 6 and wire bonding or a metal foil such as copper processed into a thin line by pressing or the like. The aluminum reflective layer 4 is not provided on 2C.

  There may be an aluminum reflective layer 4 at the tip of wire bonding, but when the aluminum reflective layer 4 does not exist, the range of bonding conditions is expanded by optimizing the surface condition of the base materials 2B and 2C. Speed and yield are improved.

  In FIG. 19, the base material 2 </ b> A of the mounting portion of the semiconductor light emitting element 6, the silver layer or silver alloy layer 3 of the pair of base materials 2 </ b> B and 2 </ b> C, and the gold flash plating layer 10 are shown in the same configuration example. The structures of the base material 2A, the base material 2B, and the silver layer of the silver alloy layer 3, and the gold flash plating layer 10 may be different or may be manufactured separately. Since this bonding is a pressure bonding with a wire or an inner lead, the main material of the bonding surface is preferably gold, silver, palladium, or an alloy in which they are the main constituent elements.

  In FIG. 19, the lower part of the base materials 2A, 2B, and 2C is illustrated as being covered with the resin of the envelope portion 8. However, the back surface of the base materials 2A, 2B, and 2C is the entire back surface, or A part of it may be exposed. The exposed material can be further connected to a metal heat radiating plate by soldering or the like, thereby improving heat dissipation and increasing the light output. Further, when the semiconductor light emitting element 6 having the back electrode is used, it is sufficient that one or more power supply terminals are used for connection to the upper electrode, and a plurality of power supply terminals connected to the upper electrode are connected by wire bonding. It doesn't matter. When a plurality of power supply terminals are used, the layout of wiring between light-emitting devices may be facilitated when driving with a large current, which is used properly.

  In FIG. 19, the connection between the electrode portion of the semiconductor light emitting element 6 and the power supply terminals of the base materials 2 </ b> B and 2 </ b> C is illustrated by wire bonding, but a lead is formed by a patterned wiring material for connection. Connection by wedge bonding using ultrasonic waves or heating may be performed.

  As described above, the present inventors have found that the carbon concentration in the aluminum reflective layer 4 greatly affects the bonding strength between the bonding wire 7 made of gold and the aluminum reflective layer 4. Note that this applies to all the embodiments described above.

  As is clear from the above description, a typical configuration example of the semiconductor light-emitting element mounting substrate of the present invention and a semiconductor light-emitting device using the same has been described based on the above embodiments and illustrated examples. The present invention is not limited to the configuration examples such as the above-described embodiments and illustrated examples, and various configurations are possible within the scope of the technical idea of the present invention. The main constituent material of the surfaces of the base materials 2B and 2C to be wire-bonded or inner-lead bonded as power supply terminals may be one selected from gold, silver, palladium, gold alloy, silver alloy, or palladium alloy, or a combination thereof. .

(Twenty-second to thirty-first embodiments)
Embodiments of a semiconductor light emitting element mounting substrate and a semiconductor light emitting device according to the present invention include a base material made of copper, a copper alloy, or an iron-based alloy on which a semiconductor light emitting element is mounted, and at least a surface side of the base material on which the semiconductor light emitting element is mounted. A semiconductor light-emitting element mounting substrate having an aluminum reflective layer provided in part and a metal layer containing titanium under the aluminum reflective layer is configured.

  As the metal of the base material, a base material made of copper or a copper alloy is desirable in terms of electric resistance and thermal resistance. Further, as the metal of the base plate, an iron nickel alloy such as 42 alloy or an iron-based frame material can be used.

  Furthermore, the base material should just contain the metal part. For example, the base material can be a copper-clad plate in which copper is laminated on a resin. In this case, the resin is formed on the surface opposite to the surface on which the aluminum reflective layer is formed on the substrate. Furthermore, the surface of the base material on the side opposite to the surface on which the aluminum reflective layer is formed may include a composite structure composed of an organic material and an inorganic material.

[Twenty-second (1) embodiment]
FIG. 20A is a schematic cross-sectional view of a semiconductor light-emitting element mounting substrate showing a twenty-first (1) embodiment of the present invention, in which 2 is a base material, 11 is a metal layer which is an example of a first metal layer, 4 is an aluminum reflective layer formed in a region including a portion where a semiconductor light emitting element is mounted on one surface of the base material 2, and 19 is a titanium layer that serves as a bonding layer of the aluminum reflective layer. It is configured. The titanium layer 19 is an example of a metal layer containing titanium. The base material 2 is comprised with the composite material of a metal or a metal, and an organic material or an inorganic material. The substrate 2 generally has a single layer of nickel or a nickel alloy or a composite layer further covered with palladium, gold or the like for solder mounting. In this embodiment, 11 metal layers (plating layers) are used. It is. The metal material is not limited to this, but the most versatile base material is a metal lead frame made of copper or a copper alloy. When using a copper plate as the base material 2, the thickness is not limited, but the thickness is selected in consideration of cost. In consideration of mass production, a copper plate hoop material is preferable, but short sheet materials and individual materials can also be used. When a composite material is used as the base material 2, a copper clad plate in which a copper plate is laminated on a resin material or a laminate thereof can be used. As the resin, a hard plate-like resin or a thin flexible resin can be used. Typical examples include glass epoxy substrates (glass cloth base resin plates) and polyimide resin systems. The manufacturing method of the aluminum reflective layer 4 and the titanium layer 19 is performed by a batch process or a continuous process, etc., using a vapor deposition apparatus having a pressure-reducing pressure adjustment function. The thickness of the aluminum reflective layer 4 is preferably 0.02 μm or more from the viewpoint of reflectance, and preferably 2 μm or less from the viewpoint of flatness.

When a copper plate is used as the base material 2, for example, the length is 100 m, the width is 50 mm, and the thickness is 0.2 mm. The thickness of the aluminum reflective layer 4 is, for example, 0.05 μm, and the thickness of the titanium layer 19 is 0.1 μm. . In production, first, a copper plate having the above-described dimensions as the base material 2 was plated with tin (1 μm) as the metal layer 11. In addition, in the case of tin, about 1-5 micrometers is preferable. Next, the titanium layer 19 and the aluminum reflective layer 4 were formed using a resistance heating type barrel-type electron beam vacuum deposition apparatus. Specifically, the base material 2 is cut so as to be a short material of 50 mm × 150 mm, and 16 pieces of the cut base materials are arranged radially on an umbrella-shaped jig having a radius of 300 mm, and three sets are arranged in a barrel. Then, as an evaporation source of aluminum and titanium, an electron beam gun (output 6 kW) was used, the degree of vacuum was evacuated to 2 × 10 ⁻⁴ Pa, and the aluminum reflective layer 4 was formed to a thickness of 0.05 μm. In this embodiment, the vacuum deposition apparatus is a self-made machine, but there is no problem even if a commercially available deposition apparatus such as a load lock type deposition apparatus is used. Further, a continuous vapor deposition apparatus capable of vapor deposition on the hoop material may be used. A vacuum deposition apparatus may be selected as appropriate in consideration of film quality, productivity, and the like. Furthermore, the formation method of the aluminum reflective layer 4 and the titanium layer 19 may not be an electron beam evaporation method. That is, a resistance heating vapor deposition method, an ion plating method, a sputtering method, a cladding method, or the like can be used.

[Twenty-second (2) embodiment]
FIG. 20B is a schematic cross-sectional view of a substrate for mounting a semiconductor light emitting device according to a twenty-second (2) embodiment of the present invention. When a copper plate is used as the base material 2, for example, the length is 100 m, the width is 50 mm, and the thickness is 0.2 mm. The thickness of the aluminum reflective layer 4 is, for example, 0.05 μm, and the thickness of the titanium layer 19 is 0.1 μm. . In production, first, a nickel-palladium plating layer material (nickel 0.7 μm, palladium 0.1 μm) was prepared as a base material 2 on a copper plate having the above-described dimensions. Next, the titanium layer 19 and the aluminum reflective layer 4 were formed using a resistance heating type barrel-type electron beam vacuum deposition apparatus. Specifically, the base material 2 is cut so as to be a short material of 50 mm × 150 mm, and 16 pieces of the cut base materials are arranged radially on an umbrella-shaped jig having a radius of 300 mm, and three sets are arranged in a barrel. Then, as an evaporation source of aluminum and titanium, an electron beam gun (output 6 kW) was used, the degree of vacuum was evacuated to 2 × 10 ⁻⁴ Pa, and the aluminum reflective layer 4 was formed to a thickness of 0.05 μm. In this embodiment, the vacuum deposition apparatus is a self-made machine, but there is no problem even if a commercially available deposition apparatus such as a load lock type deposition apparatus is used. Further, a continuous vapor deposition apparatus capable of vapor deposition on the hoop material may be used. A vacuum deposition apparatus may be selected as appropriate in consideration of film quality, productivity, and the like. Furthermore, the formation method of the aluminum reflective layer 4 and the titanium layer 19 may not be an electron beam evaporation method. That is, a resistance heating vapor deposition method, an ion plating method, a sputtering method, a cladding method, or the like can be used.

  The film thickness measurement of the aluminum reflective layer 4 and the titanium layer 19 was performed by SIMS analysis. The thickness from the surface to the point where the signal intensity is ½ of the maximum intensity of the underlying titanium layer immediately below the aluminum reflecting layer is the thickness of the aluminum reflecting layer, and the thickness of the titanium layer is the main constituent element in the underlying layer. The thickness was such that the signal intensity was ½ of the maximum intensity. When the above-mentioned base material 2 is copper, the signal strength of copper is used.

(Evaluation of examples according to the present embodiment)
About the aluminum reflective layer 4, the sulfurization characteristic and the reflectance were confirmed as follows. First, as shown in Example 33 to Example 37 of Table 5, a titanium layer is formed by plating so as to be 0.05 μm on the above-described nickel 0.7 μm and palladium 0.1 μm, and the thickness is changed. The aluminum reflective layer was prepared by the method described above, and the initial reflectance at a wavelength of 460 nm was measured. At this wavelength, the reflectance of barium sulfate was 100%, the reflectance was 90% or more and 98% or less, particularly good (indicated by ◯), and less than 90% was defective (indicated by ×). When aluminum was very thin, that is, when the thickness was 0.01 μm or less, the reflectance was lowered due to the influence of the reflectance of the underlying metal (here, palladium). Next, as for the sulfurization characteristics, 3 ppm of H ₂ S (hydrogen sulfide) was sprayed for 96 hours at an atmospheric temperature of 40 ° C. and a humidity of 80% for the above sample (test based on the corrosion resistance test method of JIS H8502 plating was performed). ) The resistance to sulfuration was defined as the ratio between the initial reflectance and the reflectance after sulfiding for 96 hours. When the aluminum reflective layer was provided, there was nothing that decreased to less than 90% of the initial reflectivity (less than 81% as reflectivity). Overall, it has been confirmed that the initial reflectance and sulfurization characteristics (that is, the reflectance after use in an environment that can be sulfided) are good as required characteristics as a substrate for mounting a semiconductor light emitting device. The thickness of the aluminum reflective layer was 0.02 μm or more.

  As Comparative Example 31, when only the silver layer of 3 μm is provided on the base material, the initial reflectance is 93% and good and good, but the sulfurization characteristic is greatly reduced to 29% after the sulfidation resistance test. And it is confirmed that it is not good. In Comparative Example 32, in which only a nickel layer (0.7 μm) and a palladium layer (0.05 μm) are provided on a base material, the anti-sulfurization property is good, but the initial reflectance is as low as 63% and x. Have confirmed.

  In Comparative Examples 33 and 34, the nickel layer 17, the palladium layer 18, and the titanium layer 19 are provided in the same manner as in Example 33, and the aluminum reflective layer thereon is thin and has sufficient initial reflection characteristics. Absent.

  According to the present embodiment, since the aluminum reflective layer and the titanium layer are formed on the surface of the base material, the substrate for mounting a semiconductor light emitting element having high and stable reflective characteristics over a long period without being sulfided and a semiconductor using the same A light emitting device can be realized. This is because the reflectance of aluminum is three times higher than that of silver in ultraviolet rays, and has a reflectance close to silver for purple, red, and infrared rays. It has the next highest reflectivity and utilizes the characteristics that sulfidation does not easily occur compared to silver.

  In order to perform wire bonding on the semiconductor light emitting element mounting substrate described above, argon plasma cleaning is performed, and then a gold wire is bonded. When this semiconductor light emitting element mounting substrate was subjected to a sulfidation test, no reduction in reflectance was observed. From this result, it was found that the resistance to surface cleaning was strong and there was no fear of deterioration or peeling. The bonding characteristics with the gold wire were confirmed for the semiconductor light emitting element mounting substrate formed by the above manufacturing method. For the wire bonder, K & S 4522 type was used, and the pull strength of bonding characteristics was tested and evaluated using a bond tester series 4000 manufactured by Dege, using a gold wire (made by Tanaka Kikinzoku, type C) having a diameter of 25 μm.

  The base material is a copper alloy without press working (C-194: thickness 0.15 mm), nickel (thickness 0.7 μm) -paradium (thickness 0.05 μm) plated, Al aluminum layer alone (thickness) And a titanium layer (thickness 0.1 μm) + aluminum layer (thickness 0.1 μm). Table 6 shows the results of the film structure and gold wire pull test (10 samples).

  As shown in Table 6, it was found that by providing the base, nickel, palladium plating, titanium layer, and aluminum reflective layer in this order, the pull strength was greatly improved and the variation could be reduced. Even without the titanium layer, the bonding characteristics are at a level where there is no practical problem. However, it was found that the semiconductor light-emitting element mounting substrate through the titanium layer has an increased pull strength and further improved the bonding characteristics. In this embodiment, nickel-palladium plating is used mainly to increase the yield and soldering conditions when soldering and mounting current-introducing terminals after the LED elements are formed. .05 μm or less) may be inserted.

  In addition, even if it formed in order of the base material, the metal layer 11 which is an example of a 1st metal layer, a titanium layer, and an aluminum reflective layer, it confirmed that the same effect was acquired.

  It should be noted that the effects obtained from the twenty-second (1) and (2) embodiments can also be obtained in the later-described embodiments, although to a different extent.

[Twenty-third embodiment]
FIG. 21 is a schematic cross-sectional view of a semiconductor light-emitting device showing a twenty-third embodiment of the present invention, and shows the semiconductor light-emitting device using the semiconductor light-emitting element mounting substrate shown in FIG. In the figure, 2 is a base material, 23 is a plating layer of the base material, 4 is an aluminum reflecting layer formed on one surface of the base material 2, and 19 is a titanium layer, which constitute a substrate for mounting a semiconductor light emitting element. In a semiconductor light emitting device, two sets (2A, 2B) are used in close proximity to the same surface. 6 is a semiconductor light emitting device mounted on the aluminum reflective layer 4A, and 7 is a bonding wire for electrically connecting the semiconductor light emitting device 6 and the aluminum reflective layer 4B. 8 surrounds the adjacent sides of the base materials 2A and 2B except for the semiconductor light emitting element 6, and the aluminum reflecting surface located on the bottom surface and the inclined surface 8b that moves away from the semiconductor light emitting element as the distance from the base material increases around the semiconductor light emitting element. A resin-made envelope portion having a recess formed by the layers 4A and 8 and 9 is a light-transmitting resin portion that fills the recess of the envelope portion 8 and seals the semiconductor light emitting element. Part. 9 can be mixed with a phosphor material. For example, by mixing YAG or the like, a 460 nm GaN LED can be used as the LED chip, and a pseudo white LED device can be used.

  The aluminum reflective layers 4A and 4B and the titanium layers 19A and 19B may be formed on the substantially entire inner surface of the envelope, or on the remaining portion excluding a part. This is because the light emitted from the light emitting element only needs to be reflected in the outer enclosure.

  As a specific method, (1) a function of shielding the area other than the envelope region is provided by the film forming apparatus for forming the aluminum reflective layer. (2) After forming the aluminum reflective layer on the entire surface, the envelope portion There are various methods, such as a method of masking the region by taping or photolithography process, and then etching away aluminum, and any of them may be used.

  According to the semiconductor light emitting device having such a configuration, light emitted from the semiconductor light emitting element 6 is formed in the concave portion by the aluminum reflective layer 4A due to the presence of the aluminum reflective layer 4A located on the bottom surface of the concave portion formed in the envelope portion 8. The light reflected from the opening side is effective in increasing the amount of light from the semiconductor light emitting device. As described above, since aluminum has a good antisulfurization characteristic, a high reflectance can be maintained for a long time.

[Twenty-fourth embodiment]
FIG. 22 is a schematic cross-sectional view of a substrate for mounting a semiconductor light emitting device, showing a twenty-fourth embodiment of the present invention. A nickel layer 17, a palladium layer 18, and a gold flash plating layer 10 are sequentially applied to both surfaces of a base material 2 by a wet plating method. The titanium layer 19 and the aluminum reflective layer 4 are formed on a part of the gold flash plating layer 10 on one side of the substrate 2. One of the reasons for sequentially forming the nickel layer 17, the palladium layer 18, and the gold flash plating layer 10 on the substrate 2 is to ensure solder wettability between the substrate 2 and the printed wiring board on which the semiconductor light emitting device is mounted. This is to improve solder connectivity. In that case, the thickness of the nickel layer 17 is 0.4 to 1.5 μm, the thickness of the palladium layer 18 is 0.01 to 0.2 μm, and the thickness of the gold flash plating layer 10 is 0.1 μm or less. it can. These thicknesses have been confirmed by the present inventors, but there are some changes depending on the elements to be mounted. The thickness of the aluminum reflective layer 4 is preferably 0.02 μm or more from the viewpoint of light reflection characteristics, and preferably 2 μm or less from the viewpoint of flatness.

  The manufacturing method of the aluminum reflective layer 4 and the titanium layer 19 is a vapor deposition apparatus having a pressure reducing function, and is performed by batch processing or continuous processing. The nickel layer and the palladium layer 18 can obtain a plating layer having a quality required for this product by either a wet plating method or a dry method such as vacuum deposition. In the wet plating, the entire surface (six sides) of the material can be coated and can be manufactured at low cost, and the nickel layer and the palladium layer 18 of the present invention are preferably formed by wet plating.

  In addition, the film thickness of the base layer formed by the wet plating method of the nickel layer 17, the palladium layer 18, and the gold flash plating layer 10 was calculated by integrating the current values during plating.

  This nickel layer has a thickness between 0.4 μm and 1.5 μm for the purpose of preventing discoloration due to oxidation of copper as a base material and improving the handling characteristics due to the fact that the substrate for mounting a semiconductor light emitting element becomes hard. Can take. When the element is mounted by soldering, the palladium layer 18 can be provided in order to obtain good solder wettability by forming the palladium layer 18 in a portion serving as a connection portion. The palladium layer 18 is often 0.01 μm to 0.2 μm in thickness, but the thickness is determined by the soldering conditions.

  The effect of this embodiment can ensure a high reflectance by using aluminum as the reflective layer. Furthermore, by using the aluminum reflecting layer 4 having a thickness of 0.02 μm or more, good durability can be obtained, and in addition to the effect that high reflectance can be maintained, the following effects can be obtained. That is, the nickel layer 17 in the above numerical range can prevent the diffusion of copper, which is the main material of the substrate 2, and the palladium layer 18 in the above numerical range can improve the wettability with the lead-free solder material during mounting. In addition, the gold flash plating layer 10 in the above numerical range has further new effects such as improvement of solder wettability and long-term storage. That is, it can be set as the structure suitable for soldering by setting it as such a structure.

[Twenty-fifth embodiment]
FIG. 23 is a schematic cross-sectional view of a semiconductor light-emitting device showing a twenty-fifth embodiment of the present invention. The semiconductor light-emitting element mounting substrate shown in FIG. 22, the envelope portion 8 and the light-transmitting resin portion 9 shown in FIG. It is an Example of the combined semiconductor light-emitting device. The same parts as those in FIGS. 21 and 22 are denoted by the same reference numerals.

  When using a copper plate as the base material 2, for example, a copper plate having a length of 100 m, a width of 50 mm, and a thickness of 0.2 mm is prepared, and the nickel layer 17 is 1 μm thick and the palladium layer 18 is 0 mm thick on the surface of the base material 2. .1 μm and a thickness of 0.01 μm of the gold flash plating layer 10 are sequentially prepared by a wet plating method. Further, the titanium layers 19A and 19B and the aluminum reflective layers 4A and 4B are left to be used for solder connection on the gold flash plating layer 10 and partially deposited on the part used as a reflective film. Rather, a material having an aluminum layer is obtained in the portion used for reflection. Thereafter, a frame shape for mounting a semiconductor light emitting element is produced by pressing or etching, and two sets (2A and 4A, 2B and 4B) are arranged close to each other on substantially the same plane. Then, a resin envelope portion 8 having a recess that surrounds the adjacent portions of the base materials 2A and 2B and has a perforated portion around the semiconductor light emitting element 6 in advance is formed. Next, the semiconductor light emitting element 6 is mounted with a conductive paste material, and the surface electrode and the lead frame are connected by gold wire bonding. Finally, a light-transmitting resin (silicon resin or the like) is filled in the concave portion of the envelope portion 8 so as to cover the semiconductor light emitting element 6 to form a light-transmitting resin portion 9 that becomes a part of the envelope. To do.

  In the above description, the semiconductor light-emitting element mounting substrate is manufactured and then formed into a predetermined shape using a press or etching, but a post-plating method may be used. That is, after the base material 2 is formed into a predetermined shape, each of the plating layers (10, 17, 18) is formed on the base material by a wet plating method, and the aluminum reflective layer 4 and the titanium layer 19 are formed by a dry plating method such as a vacuum evaporation method. It is also possible to form. Furthermore, although the base material 2 has been described with respect to the case of copper, a substrate provided with copper wiring on a resin or the like can be used. Further, from the viewpoint of use, cost, etc., other metal base materials such as iron-based 42 alloy alloy may be used. Moreover, the aluminum reflective layer 4 and the titanium layer 19 can be formed and used after the wiring is formed by a printed wiring board or flexible wiring board forming step. In this way, depending on the purpose, structure, and material (copper plate or flexible flexible resin substrate), the order of shape production (shape production by punching, bending, overhanging, etc.), plating, and vapor deposition is changed. can do.

  As the semiconductor light emitting element 6 to be mounted, for example, an LED chip such as a GaAs-Si-LED, an AlGaAs-LED, a GaP-LED, an AlGaInP-LED, or an InGaN-LED can be mounted. Further, the semiconductor light emitting element 6 shown in FIG. 13 is a vertical element on the upper and lower electrodes, but is not limited to this, and is a planar structure LED (for example, GaN) that forms a pair of electrodes on the same surface. System). In the case of a planar structure in which the electrodes are formed on the same surface, wire bonding is performed for both the cathode and the anode with the electrode surface facing the upper surface (upper side in the figure), and the electrode surface is lower (lead frame side) Although there is a so-called flip chip mounting method in which direct connection is made toward the substrate, any mounting method can be used. Copper wire bonding or aluminum wire bonding may be used instead of gold wire bonding.

  Furthermore, in this embodiment, the gold flash plating layer 10 is used, but for gold, a relatively rough pitch (for example, 0.5 mm pitch), that is, a case where high precision is not required. Even if the gold flash plating layer 10 is not provided, it is possible to exclude the gold flash plating layer 10 because a high yield is provided. Regarding the palladium layer 18, palladium can be omitted if the thickness of the metal layer is ensured and sufficient solder wettability is obtained.

  According to the semiconductor light emitting device having such a configuration, as in the semiconductor light emitting device shown in FIG. 21, the presence of the aluminum reflective layer 4A located on the bottom surface of the recess formed in the envelope portion 8 causes the semiconductor light emitting element 6 to The emitted light is reflected to the opening side of the recess by the aluminum reflecting layer 4A, and the light amount from the semiconductor light emitting device is increased. In addition, since the aluminum reflective layer 4A has good light reflection characteristics, a high reflectance can be maintained for a long time.

[Twenty-sixth embodiment]
FIG. 24 is a schematic cross-sectional view of a substrate for mounting a semiconductor light emitting element showing a twenty-sixth embodiment of the present invention. This embodiment is positioned as a modified example of the semiconductor light emitting element mounting substrate shown in FIG. 22, and FIG. 24A shows the nickel layer 17, the palladium layer 18 and the gold flash plating layer 10 only on one surface of the substrate 2. FIG. 24B shows an example in which the titanium layer 19 and the aluminum reflective layer 4 are formed on a part of the gold flash plating layer 10. FIG. An example in which the titanium layer 19 and the aluminum reflective layer 4 are partially formed, and a part thereof is bent upward by approximately 90 degrees on the paper surface. FIG. 24C shows the nickel layer 17, the palladium layer 18, and the gold on the entire surface of the substrate 2. FIG. 24D shows an example in which the flash plating layer 10 is formed, the aluminum reflective layer 4 and the titanium layer 19 are formed on the entire surface of the gold flash plating layer 10 formed, and a part thereof is bent upward 180 degrees on the paper. Shows an example in which the aluminum reflecting layer 4 and the titanium layer 19 are directly formed on one surface of the substrate 2, and the nickel layer 17, the palladium layer 18 and the gold flash plating layer 10 are formed on the other surface of the substrate 2, respectively. .

  The substrate for mounting a semiconductor light emitting device shown in FIG. 24A has a nickel layer 17 of 0.4 μm thick by plating on one side of a base material 2 made of copper, and a palladium layer 18 of 0.01 μm thick by plating. The gold flash plating layer 10 has a thickness of 0.1 μm, and a titanium layer 19 and an aluminum reflective layer 4 can be formed on a part of the gold flash plating layer 10 by vapor deposition. When nickel, palladium, gold, and aluminum are sequentially laminated on a copper substrate as in this example, a wet plating method can be used except for the aluminum reflective layer. As for the aluminum reflective layer 4 and the titanium layer 19, it is preferable to employ a vacuum deposition method because it cannot be easily plated by a wet plating method at present. As another method, for example, a sputtering method in an inert gas can be used. A plurality of these methods may be used from the viewpoints of cost, simplification of process steps, and the like.

  In the substrate for mounting a semiconductor light emitting device shown in FIG. 24B, the nickel layer 17 is plated on the base material 2 with a thickness of 1.5 μm, the palladium layer 18 is plated with a thickness of 0.2 μm, and the gold flash plating layer 10 is formed. Are sequentially formed to a thickness of 0.1 μm, and then an aluminum reflecting layer 4 and a titanium layer 19 are formed in part. The substrate for mounting a semiconductor light emitting element shown in FIG. 24C has a nickel layer 17 applied to the base material 2 with a thickness of 1.5 μm, a palladium layer 18 with a thickness of 0.2 μm, and a gold flash plating layer 10. Are sequentially formed to a thickness of 0.1 μm, and then a titanium layer 19 and an aluminum reflective layer 4 are formed on the entire surface. In these examples, it is assumed that the semiconductor light emitting element is mounted on the upper surface of the titanium layer 19 and the aluminum reflecting layer 4 and wire bonding is performed on the lower surface or side surface of the substrate 2. More specifically, the configuration is applicable when the substrate 2 is bent. In this embodiment, wire bonding is performed on the back surface of the base material 2, but the back surface may be coated with a nickel layer 17, a palladium layer 18, a gold flash plating layer 10 or the like depending on the purpose.

  The semiconductor light emitting element mounting substrate shown in FIG. 24D has the nickel layer 17, the palladium layer 18, and the gold flash plating layer 10 applied to only one surface of the substrate 2, as in the example of FIG. Therefore, the amount of these metals used can be suppressed. In the case where only one side is plated, it can be realized without the need for a mask material by laminating two substrates together and flowing them to the plating step and then separating them. As described above, the aluminum reflective layer 4 and the titanium layer 19 are easily affected by the reflectance of the base depending on the thickness. Although the aluminum reflective layer 4 and the titanium layer 19 are formed on the entire surface, the aluminum reflective layer 4 and the titanium layer 19 may be partially formed. After forming the semiconductor light emitting element mounting substrate shown in FIG. 24D, the end portion of the base material (also referred to as a substrate connection lead or outer lead) can be processed into a predetermined shape and used. For example, this configuration can be used when the lower surface of the portion (outer lead) exposed from the envelope of the base material is bent and connected to the base material so as to contact the upper surface of the printed board. That is, the central portion of the base material is used as an aluminum reflecting layer, the lower surface of the end portion of the base material is used as an outer lead, and the nickel-palladium side surface is connected to the printed circuit board.

[Twenty Seventh Embodiment]
FIG. 25 is a schematic sectional view of a substrate for mounting a semiconductor light emitting device, showing a twenty-seventh embodiment of the present invention. In this embodiment, palladium (Pd), gold (Au), tin (Sn), nickel (Ni), copper (Cu) -tin (Sn) alloy, copper (Cu)- A single metal layer 11 selected from a nickel (Ni) alloy is formed, and a titanium layer 19 and an aluminum reflective layer 4 are formed on the metal layer 11 or the substrate 2. (A) is an example in which the metal layer 11 is formed on both surfaces of the substrate 2 and the titanium layer 19 and the aluminum reflective layer 4 are formed on a part of the metal layer 11 on one surface. An example in which the metal layer 11 is formed on one surface and the titanium layer 19 and the aluminum reflective layer 4 are formed on a part of the metal layer 11, (c) forms the metal layer 11 on one surface of the substrate 2, The example which formed the titanium layer 19 and the aluminum reflective layer 4 in the other surface of the base material 2 is each shown.

  Palladium has an antioxidant effect than copper and has the advantage of being compatible with tin used in solder. Tin has the advantage of being easy to solder and inexpensive, but has the disadvantage of being somewhat easily oxidized. Copper-tin alloys are less susceptible to oxidation than copper and have the advantage of being more familiar with tin than tin and copper. Copper-nickel alloys have the advantage of being more familiar with tin than nickel. Based on these points, an optimum material for the metal layer 11 can be selected depending on the use conditions and the manufacturing conditions.

[Twenty-eighth embodiment]
FIG. 26 is a schematic cross-sectional view of a substrate for mounting a semiconductor light emitting element showing a twenty-eighth embodiment of the present invention. This embodiment is characterized in that one or a plurality of gold plating layers 12 are formed on the titanium layer 19 and the aluminum reflective layer 4. FIG. 26A shows an example in which the gold plating layer 12 is formed on the titanium layer 19 and the aluminum reflecting layer 4, and FIG. 26B shows a gold flash outside the partially formed titanium layer 19 and the aluminum reflecting layer 4. An example in which the gold plating layer 12 is formed on the plating layer 10, FIG. 26C shows an example in which the gold plating layer 12 is formed on the entire surface of the titanium layer 19 and the aluminum reflective layer 4, and FIG. An example in which the gold plating layer 12 is formed on the entire surface of the gold flash plating layer 10 on which the layer 19 and the aluminum reflective layer 4 are formed is shown. FIG. 26E shows a semiconductor light emitting device using this semiconductor light emitting element mounting substrate. The schematic sectional drawing which shows an example of this embodiment is shown. In these examples, the nickel layer 17, the palladium layer 18 and the gold flash plating layer 10 are sequentially formed on the entire surface of the substrate 2, but the present invention is not limited thereto. The present invention can also be applied to the case where the single metal layer 11 is formed, or the titanium layer 19 and the aluminum reflective layer 4 are directly formed on the substrate 2.

  The gold plating layer 12 in this embodiment can be used for electrical connection of a semiconductor light emitting element mounted on the titanium layer 19 and the aluminum reflective layer 4. The thicker the gold plating layer, the lower the reflectance on the short wavelength side (blue) side, but the gold wire connectivity is improved. Depending on the application, the structure of the gold plating layer 12 may be determined in consideration of the reflectance. In addition, although each plating layer (10, 12, 17, 18) was formed by the wet plating method here, you may form by another system.

[Twenty-ninth embodiment]
FIG. 27 is a schematic view showing a typical use state of a semiconductor light emitting device as a 29th embodiment of the present invention. The semiconductor light emitting device according to the present embodiment is used by being mounted on, for example, a printed wiring board using the semiconductor light emitting element mounting substrate 1 according to the twenty-second to twenty-eighth embodiments. A portion (outer lead) extending outward from the envelope portion 8 of the semiconductor light emitting element mounting substrate 1 to be mounted on the printed wiring board 13 is bent to be substantially flush with the lower surface of the envelope portion 8. 1a or portions 1b and 1c located below the lower surface are formed. This portion is bonded to the wiring of the printed wiring board 13 with solder 14. In FIG. 27A, the outer lead is bent 90 degrees and directed downward, and the outer lead is bent 90 degrees in the opposite direction and directed in the horizontal direction, so that the horizontal position of the envelope portion 8 remains unchanged with the outer lead extending in the same direction. FIG. 27B shows an example in which a portion 1 a having substantially the same surface as the lower surface is formed. FIG. 27B shows that the outer lead is bent 90 degrees twice along the envelope portion 8 along the lower surface of the envelope portion 8. FIG. 27 (c) shows an example in which the portion 1b is formed. FIG. 27 (c) shows that the outer lead is bent 90 degrees twice along the envelope portion 8 in the opposite direction to FIG. 27 (b). The example which formed the part 1c along is shown, respectively. The method of bending the outer lead is not limited to this, and a shape suitable for each application in which the semiconductor light emitting device is used is adopted.

  A semiconductor light emitting element mounting substrate in which a 14 nickel layer and a palladium layer are provided on the contact surface side of the solder 14 is more preferable than a semiconductor light emitting element mounting substrate in which the first metal layer 11 is provided.

[Thirty Embodiment]
The present embodiment is the same as the other embodiments in that an aluminum reflective layer is provided on the substrate as in the twenty-second embodiment. However, the carbon concentration of the aluminum reflective layer is 1 × 10 ²⁰ pieces / cm ³ or less. In order to evaluate the bondability with the semiconductor light emitting element mounting substrate, a bonding wire made of gold and wire bonding were performed. Here, the wire bonding means that a lead frame side electrode pad and an electrode on an element mounted on the lead frame are connected with a wire such as gold in order to electrically connect them.

  The 1st bonding is to first bond a wire whose tip is made spherical by electric discharge. Usually, the electrode on the element side is often 1st bonding in view of positional accuracy and pressure-bonding properties. In this embodiment, an aluminum reflective layer provided on a copper base material in the same manner as in the first embodiment was bonded to a wire whose tip was made spherical by electric discharge.

  The 2nd bonding means bonding at a predetermined position between the electrode on the element side and the electrode on the lead frame side to be connected with the wire. In this example, the end of the wire was pressure-bonded in such a manner that it was rubbed onto a copper base material provided with an aluminum reflective layer as in the twenty-second embodiment.

Table 8 shows the relationship between the carbon concentration in the aluminum reflective layer and the bonding strength between the gold wires. As Example 38, a nickel layer of 0.7 μm and palladium of 0.05 μm formed by a wet plating method on a copper substrate thickness of 0.15 mm was punched and pressed to form three layers having a thickness of 0.5 mm. A circuit board for light-emitting devices is formed on a glass epoxy substrate with a heat-resistant acrylic resin adhesive. This material was attached to the above-described vacuum deposition apparatus, a titanium layer was formed with a thickness of 0.1 μm, and an aluminum reflective layer was formed with a thickness of 0.2 μm, and SIMS analysis was performed. Here, the carbon concentration in the aluminum reflecting layer was set to the minimum carbon concentration in the aluminum reflecting layer. The carbon concentration in the aluminum reflective layer was 3 × 10 ²⁰ pieces / cm ³ . For the base material of Example 39, a polyimide resin film having a thickness of 125 μm and a copper base material of 70 μm, a nickel layer of 0.7 μm and palladium of 0.05 μm formed by a wet plating method is bonded together with a heat-resistant acrylic resin adhesive. Board material. In Example 39, after forming the aluminum reflective layer, the wiring material was formed by punching and pressing the separation part. When the carbon concentration in the aluminum reflective layer of Example 39 was similarly analyzed, the carbon concentration in the aluminum reflective layer was 1 × 10 ²⁰ pieces / cm ³ . In Example 40, an iron-plated copper alloy having a nickel layer of 0.7 μm and palladium of 0.05 μm formed by wet plating was simply punched and pressed into a vacuum vapor deposition apparatus made of stainless steel (SUS304). The titanium layer 19 was formed with a thickness of 0.1 μm, and the aluminum reflective layer 4 was formed with a thickness of 0.2 μm. The carbon concentration in the aluminum reflective layer of Example 40 was 3 × 10 ¹⁹ atoms / cm ³ .

  In Example 38, the thickness of the titanium layer was 0.1 μm, but the same effect can be obtained if the thickness of the titanium layer is 0.01 μm or more. However, the thickness of the titanium layer is preferably 0.05 μm or more in consideration of the stability of the film formation process. Further, when the thickness of the titanium layer is 0.2 μm or more, the flatness gradually decreases. Therefore, the thickness of the titanium layer is preferably 0.2 μm or less.

  As the evaluation criteria, the first bonding strength was evaluated as “◯” when the shear strength was 0.39 N or more, and “x” when less than 0.39 N. The 2nd bonding strength was evaluated as “◯” when the shear strength was 0.049 N or more, and “x” when less than 0.049 N.

From Table 8, it can be seen that when the carbon concentration of the aluminum reflective layer is 3 × 10 ²⁰ pieces / cm ³ or more, the bonding strength decreases, and it is preferable to set the carbon concentration to 1 × 10 ²⁰ pieces / cm ³ or less. In this embodiment, an organic material such as an epoxy material or an acrylic adhesive increases the carbon concentration in the aluminum reflecting layer. However, the contamination of the substrate, purge gas, When the reverse diffusion of the vacuum pump oil or the sputtering method is used, various factors such as impurities in the sputtering gas can be considered.

  For bonding tests, the wire bonder is WEST BOND INC. Model 7700D was used, a gold wire with a diameter of 25 μm was used, the bonding conditions were an ultrasonic intensity of 350 mW, and the ultrasonic wave application time was 100 ms. The test was conducted in the share test mode of the bonding tester PTR-1 of Resuka Co., Ltd. The SIMS measurement was carried out using ADEPT1010 manufactured by PHI and using cesium ions as the primary ion source at an acceleration energy of 3 keV.

[Thirty-first embodiment]
FIG. 28 is a schematic sectional view of a semiconductor light emitting device showing a thirty-first embodiment of the present invention. The feature of this embodiment is that the semiconductor light emitting element 6 is mounted on the aluminum reflective layer 4 and the power supply terminal base materials 2B and 2C for wire bonding or inner lead bonding wiring to the semiconductor light emitting element 6 are made of aluminum. That is, there is no reflective layer 4.

  The aluminum reflective layer 4 may be present at the wire bonding destination, but when the aluminum reflective layer 4 is not present, the range of bonding conditions is expanded by optimizing the surface conditions of the base materials 2B and 2C, and the assembly speed and step It may be better. FIG. 28 shows an example of the same configuration of the plating layers (3, 10) of the substrate 2A and the substrates 2B, 2C of the mounting portion of the semiconductor light emitting element 6, but the plating layers of the substrates of 2A, 2B, 2C are shown. The configuration may be different or may be produced separately. FIG. 28 shows the case where the lower portions of the base materials 2A, 2B, and 2C are covered with the resin, but the back surfaces of the base materials 2A, 2B, and 2C may be exposed entirely or partially on the back surface. The exposed material can be further connected to a metal heat radiating plate by soldering or the like, so that the heat dissipation can be improved and the light output can be increased. When the semiconductor light emitting device 6 having the back electrode is used, it is sufficient that one or more power supply terminals are used for connection to the upper electrode, and a plurality of power supply terminals connected to the upper electrode may be wire-bonded. Absent. In the case where a plurality of devices are used, there are cases where the layout of the wiring between the light emitting devices is facilitated when driving with a large current.

  FIG. 28 shows the case of wire bonding connection between the electrode portion of the light emitting element and the power supply terminal. However, an inner lead made of a patterned wiring material for connection is prepared, and a wedge using ultrasonic waves or heating is used. Connection by bonding may be performed.

  As described above, the inventors have found that the carbon concentration in the aluminum reflecting layer has a great influence on the bonding strength between the gold wire and the aluminum reflecting layer. Note that this applies to all the embodiments described above.

  The semiconductor light-emitting element mounting substrate of the present invention and the semiconductor light-emitting device using the same are described in the representative configuration example shown as the embodiment. The present invention is not limited to this configuration example, and the technology of the present invention Various configurations are possible within the scope of the idea. The main constituent material of the surfaces of the base materials 2B and 2C to be wire-bonded or inner-lead bonded as power supply terminals may be one selected from gold, silver, palladium, gold alloy, silver alloy, or palladium alloy, or a combination thereof. . Moreover, it is possible to combine arbitrarily the component of said each embodiment within the range of the summary of this invention.

(32nd to 38th embodiments)
Embodiments of a semiconductor light emitting element mounting substrate and a semiconductor light emitting device according to the present invention include a base material made of copper, a copper alloy, or an iron-based alloy on which a semiconductor light emitting element is mounted, and at least a surface side of the base material on which the semiconductor light emitting element is mounted. A semiconductor light-emitting element mounting substrate having an aluminum reflective layer provided in part and a silver layer or a silver alloy layer under the aluminum reflective layer is configured.

[Thirty-second embodiment]
FIG. 29 is a schematic cross-sectional view of a substrate for mounting a semiconductor light emitting device showing a thirty-second embodiment of the present invention. In FIG. 29, 2 includes a base material, 4 includes a portion on which a semiconductor light emitting device on one surface of the base material 2 is mounted. An aluminum reflecting layer 19 formed in the region is a titanium layer that becomes a bonding layer of the aluminum reflecting layer 4, and these constitute a substrate for mounting a semiconductor light emitting element.

  The substrate 2 is composed of a metal or a composite material of a metal and an organic material or an inorganic material. The base material 2 is covered with a silver layer or a silver alloy layer 3 mainly for solder mounting.

  Although the base material 2 is not limited to this as the metal material of the base material 2, the most versatile base material 2 is a metal lead frame made of copper or a copper alloy. When using a copper plate as the base material 2, the thickness is not limited, but the thickness is selected in consideration of cost. In consideration of mass production, a copper plate hoop material is preferable, but short sheet materials and individual materials can also be used. When a composite material is used as the base material 2, a copper clad plate in which a copper plate is laminated on a resin material or a laminate thereof can be used. As the resin, a hard plate-like resin or a thin flexible resin can be used. Typical examples include glass epoxy substrates (glass cloth base resin plates) and polyimide resin systems.

  The manufacturing method of the aluminum reflective layer 4 and the titanium layer 19 is performed by a batch process or a continuous process, etc., using a vapor deposition apparatus having a function of adjusting a reduced pressure. The thickness of the aluminum reflective layer 4 is preferably 0.02 μm or more from the viewpoint of reflectivity.

When the copper alloy material C-194 is used as the base material 2, for example, the length is 100 m, the width is 50 mm, the thickness is 0.15 mm, the thickness of the aluminum reflective layer 4 is 0.05 μm, and the thickness of the titanium layer 19 is, for example. The thickness was 0.1 μm. In production, first, a silver layer or a silver alloy layer (thickness 3 μm) 3 was prepared as a base material 2 on a copper plate having the above-described dimensions by a wet plating method. Next, the aluminum reflective layer 4 and the titanium layer 19 were formed using a resistance heating type barrel-type electron beam vacuum deposition apparatus. Specifically, the base material 2 is cut so as to be a short material of 50 mm × 150 mm, and 16 pieces of the cut base materials are arranged radially on an umbrella-shaped jig having a radius of 300 mm, and three sets are arranged in a barrel. Then, as an evaporation source of aluminum and titanium, an electron beam gun (output 6 kW) was used, the degree of vacuum was evacuated to 2 × 10 ⁻⁴ Pa, and the aluminum reflective layer 4 was formed to a thickness of 0.05 μm. In this embodiment, the vacuum deposition apparatus is a self-made machine, but there is no problem even if a commercially available deposition apparatus such as a load lock type deposition apparatus is used. Further, a continuous vapor deposition apparatus capable of vapor deposition on the hoop material may be used. A vacuum deposition apparatus may be selected as appropriate in consideration of film quality, productivity, and the like. Furthermore, the formation method of the aluminum reflective layer 4 and the titanium layer 19 may not be an electron beam evaporation method. That is, a resistance heating vapor deposition method, an ion plating method, a sputtering method, a cladding method, or the like can be used.

  The film thickness measurement of the aluminum reflective layer 4 and the titanium layer 19 was performed by SIMS analysis. The thickness from the surface to the point where the signal intensity is ½ of the maximum intensity of the underlying titanium layer 19 immediately below the aluminum reflecting layer 4 is the thickness of the aluminum reflecting layer 4, and the thickness of the titanium layer 19 is the main constituent element The thickness was such that the signal intensity was ½ of the maximum intensity in the underlayer. In the case of the silver layer or the silver alloy layer 3 described above, the signal intensity ratio of silver is used.

(Evaluation of examples according to the present embodiment)
About the aluminum reflective layer 4, the sulfurization characteristic and the reflectance were confirmed as follows. First, as shown in Table 9, the aluminum reflective layer 4 was produced by the above-described method on a material obtained by silver plating on a copper base material, and this time, using an oven DT-31 type manufactured by Yamato Scientific Co., Ltd. Heat treatment was carried out at 150 ° C. for 4 hours continuously at 3 ° C. After the heat treatment, the initial reflectance at a wavelength of 460 nm was measured. At this wavelength, the reflectance of barium sulfate was 100%, the reflectance of 90% or more was particularly good (indicated by ◯), and the reflectance of less than 90% was defective (indicated by x).

  Next, regarding the sulfuration characteristics, 3 ppm of H2S (hydrogen sulfide) was exposed for 48 hours at an atmospheric temperature of 40 ° C. and a humidity of 80% for the sample in which the aluminum reflective layer 4 and the titanium layer 19 having a thickness of 0.1 μm were formed ( The test based on the JIS H8502 plating corrosion resistance test method was conducted). The resistance to sulfuration was defined as the ratio between the initial reflectance and the reflectance after sulfiding for 48 hours. As a result, it was found that the initial reflectance was 92%, while the reflectance after the sulfidation resistance test was 87%.

  In Example 44, a silver layer having a thickness of 3 μm on the substrate 2 or an aluminum reflective layer 4 having a thickness of 0.1 μm provided on the silver alloy layer 3 is not subjected to heat treatment. The reflectivity was 91% and good and good, but the sulfurization characteristics confirmed that the reflectivity ratio after the anti-sulfurization test was as good as 98%. As Comparative Example 45, a silver layer having a thickness of 3 μm on the substrate 2 or an aluminum reflective layer 4 having a thickness of 0.1 μm provided on the silver alloy layer 3 (ie, Example 44) was heat-treated under the above conditions. In this case, it was confirmed that the initial reflectance was reduced to 62% and x, and the sulfurization characteristic (initial reflectance ratio) was decreased to 55%.

  From Example 44 and Comparative Example 45, when heat treatment was performed, copper diffused to the surface of the substrate for mounting a semiconductor light emitting device, and deteriorated the initial reflectance and antisulfuration characteristics (deteriorated heat resistance). When the titanium layer is provided, heat resistance can be maintained high by serving as a copper diffusion barrier.

  According to the present embodiment, since the aluminum reflective layer 4 and the titanium layer 19 are formed on the surface of the base material 2, the semiconductor light-emitting element mounting substrate having high and stable reflective characteristics over a long period without being sulfided, and The semiconductor light emitting device used can be realized. This is because the reflectance of aluminum is three times higher than that of silver in ultraviolet rays, and has a reflectance close to silver for purple, red, and infrared rays. It has the next highest reflectivity and utilizes the characteristics that sulfidation does not easily occur compared to silver.

  In order to perform wire bonding on the semiconductor light emitting element mounting substrate described above, argon plasma cleaning is performed, and then a gold wire is bonded. When this semiconductor light emitting element mounting substrate was subjected to a sulfidation test, no reduction in reflectance was observed. From this result, it was found that the resistance to surface cleaning was strong and there was no fear of deterioration or peeling. The bonding characteristics with the gold wire were confirmed for the semiconductor light emitting element mounting substrate formed by the above manufacturing method.

  The wire bonder was model 4522 of K & S, and the pull strength of the bonding characteristics was tested and evaluated using a gold wire with a diameter of 25 μm (Tanaka Kikinzoku, type C). The base material was a copper alloy without press working (C-194: thickness 0.15 mm) silver-plated, and the titanium layer 19 was 0.1 μm + the aluminum reflective layer 4 was 0.1 μm. Table 7 shows the film structure and the results of the gold wire pull test.

  As shown in Table 7, when the titanium layer 19 is placed in the middle of the silver layer on the copper base material or the silver alloy layer 3 and the aluminum reflective layer 4, it is found that the pull strength shows a practically sufficient strength. It was.

  The effects obtained from the thirty-second embodiment can also be obtained in the later-described embodiments, albeit to some extent.

[Thirty-third embodiment]
FIG. 30 is a schematic cross-sectional view of a semiconductor light-emitting device showing a thirty-third embodiment of the present invention, and shows the semiconductor light-emitting device using the semiconductor light-emitting element mounting substrate shown in FIG. In the figure, 2 is a base material, 3 is a silver layer or a silver alloy layer of the base material 2, 4 is an aluminum reflecting layer formed on one surface of the base material 2, and 19 is a titanium layer. An element mounting substrate 1 is configured.

  In the semiconductor light emitting device 5, two sets (2A, 2B) are arranged in close proximity to each other and used. Reference numeral 6 denotes a semiconductor light emitting element mounted on the aluminum reflective layer 4, and 7 denotes a bonding wire for electrically connecting the semiconductor light emitting element 6 and the aluminum reflective layer 4. 8 surrounds the adjacent sides of the base materials 2A and 2B except for the semiconductor light emitting element 6, and is positioned on the inclined surface 8b and the bottom surface that are separated from the semiconductor light emitting element 6 as the distance from the base material 2 is increased around the semiconductor light emitting element 6. A resin-made envelope portion having a recess 8a formed of an aluminum reflective layer 4 is formed, and 9 is a light-transmitting resin portion that fills the recess 8a of the envelope portion 8 and seals the semiconductor light emitting element 6. It constitutes a part of the envelope. A phosphor material can be mixed in the envelope portion 8. For example, by mixing YAG or the like, a 460 nm GaN LED can be used as the LED chip, and a pseudo white LED device can be used.

  The aluminum reflective layer 4 and the titanium layer 19 may be formed on substantially the entire inner surface of the envelope, or on the remaining portion excluding a part thereof. The reason is that the light emitted from the semiconductor light emitting element 6 only needs to be reflected in the envelope portion 8.

  As a specific method, (1) a function of shielding other than the envelope region is provided by a film forming apparatus for forming the aluminum layer. (2) After forming the aluminum layer on the entire surface, the envelope portion region is formed. There are various methods such as a method of masking by taping or a photolithography process, and then etching away aluminum, and any of them may be used.

  According to the semiconductor light emitting device 5 having such a configuration, light emitted from the semiconductor light emitting element 6 is transmitted by the aluminum reflective layer 4 due to the presence of the aluminum reflective layer 4 located on the bottom surface of the recess 8 a formed in the envelope portion 8. The light reflected from the opening side of the recess 8a has an effect of increasing the amount of light from the semiconductor light emitting device 5. As described above, since aluminum has good resistance to sulfidation, high reflectance can be maintained for a long time.

  In the above description, the semiconductor light-emitting element mounting substrate 1 is manufactured and then formed into a predetermined shape using a press or etching, but a post-plating method may be used. That is, after the bases 2A and 2B are formed into a predetermined shape, a silver layer or a silver alloy layer 3 is formed on the bases 2A and 2B by a wet plating method, and then the aluminum reflective layer 4 is formed by a dry plating method such as a vacuum evaporation method. It is also possible to form the titanium layer 19. The silver layer or the silver alloy layer 3 is generally formed by wet plating, but may be formed by dry plating such as vacuum deposition. Furthermore, as for the base materials 2A and 2B, the case of being made of copper has been described. Further, from the viewpoint of use, cost, etc., other metal base materials such as iron-based 42 alloy alloy may be used. In addition, the titanium layer 19 and the aluminum reflective layer 4 can be formed and used after the wiring is formed by a printed wiring board or flexible wiring board forming process. In this way, depending on the purpose, structure, and material (copper plate or flexible flexible resin substrate), the order of shape production (shape production by punching, bending, overhanging, etc.), plating, and vapor deposition is changed. can do.

  As the semiconductor light emitting element 6 to be mounted, for example, an LED chip such as a GaAs-Si-LED, an AlGaAs-LED, a GaP-LED, an AlGaInP-LED, or an InGaN-LED can be mounted. Further, the semiconductor light emitting device 6 shown in FIG. 30 is a vertical element on the upper and lower electrodes, but is not limited to this, and is a planar structure LED (for example, GaN) that forms a pair of electrodes on the same surface. System). In the case of a planar structure in which the electrodes are formed on the same surface, wire bonding is performed for both the cathode and the anode with the electrode surface facing the upper surface (upper side in the figure), and the electrode surface is lower (lead frame side) Although there is a so-called flip chip mounting method in which direct connection is made toward the substrate, any mounting method can be used. Copper wire bonding or aluminum wire bonding may be used instead of gold wire bonding.

  According to the semiconductor light emitting device 5 having such a configuration, light emitted from the semiconductor light emitting element 6 is transmitted by the aluminum reflective layer 4 due to the presence of the aluminum reflective layer 4 located on the bottom surface of the recess 8 a formed in the envelope portion 8. The light reflected from the opening side of the recess 8a has an effect of increasing the amount of light from the semiconductor light emitting device 5. Moreover, since the aluminum reflective layer 4 has favorable light reflectivity, a high reflectance can be maintained over a long time.

[Thirty-fourth embodiment]
FIG. 31 is a schematic cross-sectional view of a substrate for mounting a semiconductor light emitting device showing a thirty-fourth embodiment of the present invention. This embodiment is positioned as a modification of the semiconductor light emitting element mounting substrate shown in FIG. 29, and FIG. 31 (a) forms a silver layer or a silver alloy layer 3 only on one surface of the substrate 2. An example in which the titanium layer 19 and the aluminum reflective layer 4 are formed on a part of the silver layer or the silver alloy layer 3, FIG. 31 (b) shows the silver layer formed on one surface of the substrate 2 or An example in which a titanium layer 19 and an aluminum reflective layer 4 are formed on a part of the silver alloy layer 3 and a part thereof is bent upward by approximately 90 degrees on the paper surface, FIG. An example in which the titanium layer 19 and the aluminum reflecting layer 4 are formed on the entire surface of the silver alloy layer 3 and a part thereof is bent upward by 180 degrees on the paper surface, FIG. 31 (d) shows the titanium layer 19 directly on one surface of the substrate 2. The aluminum reflective layer 4 is formed, and the nickel layer 17, the palladium layer 18, and the gold film are formed on the other surface of the substrate 2 as an example. An example in which the rush plating layer 10 is formed is shown.

  In the substrate for mounting a semiconductor light emitting device shown in FIG. 31A, a silver layer or a silver alloy layer 3 is formed by 3 μm on one side of a base 2 made of copper by a plating method, and the silver layer or the silver alloy layer 3 is formed. A titanium layer 19 and an aluminum reflecting layer 4 can be formed on a part of the film by a vapor deposition method. When silver, titanium, and aluminum are sequentially laminated on the copper base 2 as in this example, the silver layer or the silver alloy layer 3 may be dry, but a wet plating method can be used. As for the silver layer, the silver alloy layer 3, the titanium layer 19, and the aluminum reflecting layer 4, it is preferable to employ a vacuum deposition method because it cannot be easily plated by a wet plating method. As another method, for example, a sputtering method in an inert gas can be used. A plurality of these methods may be used from the viewpoints of cost, simplification of process steps, and the like.

  In the substrate for mounting a semiconductor light emitting element shown in FIG. 31B, a silver layer or a silver alloy layer 3 is formed on a base material 2 by a thickness of 3.0 μm by plating, and then a titanium layer 19 and an aluminum reflecting layer are partially formed. 4 is formed. In the semiconductor light emitting element mounting substrate shown in FIG. 31 (c), a silver layer or a silver alloy layer 3 is formed on a base material 2 by a thickness of 3.0 μm by plating, and then a titanium layer 19 and an aluminum reflective layer are partially formed. 4 is formed. In these examples, it is assumed that the semiconductor light emitting element is mounted on the upper surface of the titanium layer 19 and the aluminum reflective layer 4 and wire bonding is performed on the lower surface or side surface of the substrate 2. More specifically, the configuration is applicable when the substrate 2 is bent. In this embodiment, wire bonding is performed on the back surface of the substrate 2, but the back surface may be coated with a silver layer, or a nickel layer 17, a palladium layer 18, a gold flash plating layer 10, or the like depending on the purpose. I do not care.

[Thirty-fifth embodiment]
FIG. 32 is a schematic cross-sectional view of a substrate for mounting a semiconductor light emitting device showing a thirty-fifth embodiment of the present invention. This embodiment is characterized in that one or a plurality of gold plating layers 12 are formed on the silver layer or silver alloy layer 3, the titanium layer 19, and the aluminum reflecting layer 4. FIG. 32A shows an example in which the gold plating layer 12 is formed on the silver layer or silver alloy layer 3, the titanium layer 19, and the aluminum reflecting layer 4, and FIG. 32B shows a partially formed titanium layer 19 and aluminum. An example in which the gold plating layer 12 is formed on the silver layer or the silver alloy layer 3 outside the reflection layer 4, FIG. 32C shows the titanium layer 19 and the gold plating layer 12 formed on the entire surface of the aluminum reflection layer 4. For example, FIG. 32D shows an example in which the gold plating layer 12 is formed on the entire surface of the silver layer or the silver alloy layer 3 on which the titanium layer 19 and the aluminum reflective layer 4 are formed.

  The gold plating layer 12 in this embodiment can be used for electrical connection of a semiconductor light emitting element mounted on the titanium layer 19 and the aluminum reflective layer 4. As the gold plating layer 12 becomes thicker, the reflectance on the short wavelength side (blue) side is lowered, but the connectivity of the gold wire is improved. Depending on the application, the structure of the gold plating layer 12 may be determined in consideration of the reflectance. Here, the gold plating layer 12 is formed by a wet plating method, but may be formed by other methods.

[Thirty-sixth embodiment]
A semiconductor light-emitting device will be described as a thirty-sixth embodiment of the present invention. A typical use state of the present embodiment is the same as FIG. The semiconductor light emitting device of the present invention is used by being mounted on a printed circuit board, for example. In order to mount on the printed circuit board 13, a portion (outer lead) extending outward from the envelope portion 8 of the semiconductor light emitting element mounting substrate 1 typified by the thirty-second to thirty-fifth embodiments is bent to provide an envelope. A portion 1a that is substantially flush with the lower surface of the portion 8 or portions 2b and 2c positioned below the lower surface are formed. This portion is bonded to the wiring of the printed circuit board 13 with solder 14. In FIG. 27A, the outer lead is bent 90 degrees and directed downward, and the outer lead is bent 90 degrees in the opposite direction and directed in the horizontal direction, so that the horizontal position of the envelope portion 8 remains unchanged with the outer lead extending in the same direction. FIG. 27B shows an example in which a portion 1 a having substantially the same surface as the lower surface is formed. FIG. 27B shows that the outer lead is bent 90 degrees twice along the envelope portion 8 along the lower surface of the envelope portion 8. FIG. 27 (c) shows an example in which the portion 1b is formed. FIG. 27 (c) shows that the outer lead is bent 90 degrees twice along the envelope portion 8 in the opposite direction to FIG. 27 (b). The example which formed the part 1c along is shown, respectively. The method of bending the outer lead is not limited to this, and a shape suitable for each application in which the semiconductor light emitting device is used is adopted.

[Thirty-seventh embodiment]
In the present embodiment, similarly to the thirty-second embodiment, a silver or silver alloy layer, a titanium layer, and an aluminum reflecting layer are provided on the substrate 2. However, the carbon concentration of the aluminum reflective layer 4 is 1 × 10 ²⁰ pieces / cm ³ or less.

  In order to evaluate the bondability with the semiconductor light emitting element mounting substrate, a bonding wire made of gold and wire bonding were performed. Here, the wire bonding means that a lead frame side electrode pad and an electrode on an element mounted on the lead frame are connected with a wire such as gold in order to electrically connect them. The 1st bonding is to first bond a wire whose tip is made spherical by electric discharge. Usually, the electrode on the element side is often 1st bonding in view of positional accuracy and pressure-bonding properties. In the present embodiment, an aluminum reflective layer 4 provided on a copper substrate plate in the same manner as in the thirty-second embodiment was bonded to a wire whose tip was made spherical by discharge.

  The 2nd bonding means bonding at a predetermined position between the electrode on the element side and the electrode on the lead frame side to be connected with the wire. In this example, the end of the wire was pressure-bonded in a form of rubbing on a copper substrate plate provided with the aluminum reflective layer 4 as in the thirty-second embodiment.

Table 10 shows the relationship between the carbon concentration in the aluminum reflective layer 4 and the bonding strength between the gold wires. As Example 47, what formed the silver layer 3.0micrometer by the wet-plating method on the copper base material thickness 0.15mm was punch-pressed, and a 0.5-mm-thick 3 layer glass epoxy board was used. It is a product in which a light-emitting device circuit board is formed with a heat-resistant acrylic resin adhesive. This material was attached to the above-described vacuum deposition apparatus, a titanium layer was formed with a thickness of 0.1 μm, and an aluminum reflective layer was formed with a thickness of 0.2 μm, and SIMS analysis was performed. Here, the carbon concentration in the aluminum reflecting layer was set to the minimum carbon concentration in the aluminum reflecting layer. The carbon concentration in the aluminum layer was 3 × 10 ²⁰ pieces / cm ³ .

The base material 2 of Example 48 is a plate material in which a polyimide base film having a thickness of 125 μm and a copper base material of 70 μm and a silver layer of 3.0 μm formed by a wet plating method is bonded with an acrylic resin adhesive. In Example 48, after forming the aluminum reflective layer 4, a wiring member was formed by punching and pressing the separation portion. When the carbon concentration in the aluminum reflective layer 4 of Example 48 was similarly analyzed, the carbon concentration in the aluminum reflective layer 4 was 1 × 10 ²⁰ pieces / cm ³ .

In Example 49, an iron-coated copper alloy formed by forming a nickel layer of 0.7 μm and palladium of 0.05 μm by a wet plating method, punched and pressed into a vacuum deposition apparatus, made of stainless steel (SUS304) The titanium layer 19 was formed with a thickness of 0.1 μm, and the aluminum reflective layer 4 was formed with a thickness of 0.2 μm. The carbon concentration in the aluminum reflective layer 4 of Example 49 was 3 × 10 ¹⁹ pieces / cm ³ .

  As the evaluation criteria, the first bonding strength was evaluated as “◯” when the shear strength was 0.39 N or more, and “x” when less than 0.39 N. The 2nd bonding strength was evaluated as “◯” when the shear strength was 0.049 N or more, and “x” when less than 0.049 N.

From Table 10, it can be seen that when the carbon concentration of the aluminum reflective layer 4 is 3 × 10 ²⁰ pieces / cm ³ or more, the bonding strength decreases, and it is preferable to set the carbon concentration to 1 × 10 ²⁰ pieces / cm ³ or less.

  In this embodiment, the carbon concentration in the aluminum layer is increased by using an organic material such as an epoxy material or an acrylic adhesive, but the contamination of the base material, purge gas, vacuum, etc. When pump oil back diffusion or sputtering is used, various factors such as impurities in the sputtering gas can be considered.

  For the bonding test, MODEL 4522 of Kulicke & Soffa Industries, Inc. was used as the wire bonder, a gold wire with a diameter of 25 μm was used, the bonding conditions were an ultrasonic intensity of 1 W, and the ultrasonic wave application time was 25 ms. The test was conducted in the share test mode of the bonding tester PTR-1 of Resuka Co., Ltd. The SIMS measurement was carried out using ADEPT1010 manufactured by PHI and using cesium ions as the primary ion source at an acceleration energy of 3 keV.

[Thirty-eighth embodiment]
FIG. 33 is a schematic sectional view of a semiconductor light emitting device showing a thirty-eighth embodiment of the present invention. The feature of this embodiment is that the semiconductor light emitting element 6 is mounted on the aluminum reflective layer 4 and the base materials 2B and 2C of the power supply terminal portion for wire bonding or inner lead bonding wiring with the semiconductor light emitting element 6 are made of aluminum. That is, there is no reflective layer 4.

  The aluminum reflective layer 4 may be present at the wire bonding destination, but when the aluminum reflective layer 4 is not present, the range of bonding conditions is expanded by optimizing the surface conditions of the base materials 2B and 2C, and the assembly speed and step It may be better. Although FIG. 33 shows the case where the lower portions of the base materials 2A, 2B, and 2C are covered with the resin, the entire back surface or a part of the back surface of the base material 2 may be exposed on the back surface. The exposed one can be further connected to a metal heat radiating plate by soldering or the like, so that the heat radiation can be improved and the light output can be increased. When the semiconductor light emitting device 6 having the back electrode is used, it is sufficient that one or more power supply terminals are used for connection to the upper electrode, and a plurality of power supply terminals connected to the upper electrode may be wire-bonded. Absent. In the case where a plurality of devices are used, there are cases where the layout of the wiring between the light emitting devices is facilitated when driving with a large current.

  FIG. 33 shows the case of wire bonding connection between the electrode portion of the light-emitting element and the power supply terminal. An inner lead is formed from a patterned wiring material for connection, and a wedge using ultrasonic waves or heating is used. Connection by bonding may be performed.

  As described above, the inventors have improved the heat resistance of the titanium layer 19 between the silver layer or the silver alloy layer 3 and the aluminum reflective layer 4 with respect to the reflectance of the material, that is, the reflection characteristics and the sulfurization resistance after the heat treatment. Thus, the inventors have found that a good reflectance can be maintained even in a sulfur atmosphere. Note that this applies to all the embodiments described above.

  The semiconductor light-emitting element mounting substrate of the present invention and the semiconductor light-emitting device using the same are described in the representative configuration example shown as the embodiment. The present invention is not limited to this configuration example, and the technology of the present invention Various configurations are possible within the scope of the idea.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 1a-1c ... Substrate part, 2, 2A, 2B, 2C ... Base material, 3 ... Silver layer or silver alloy layer, 4, 4A, 4B ... Aluminum reflective layer, 5 ... Semiconductor light-emitting device, 6 ... Semiconductor light emitting element (LED chip), 7 ... bonding wire, 8 ... envelop part, 8a ... concave, 8b ... inclined surface, 9 ... light transmissive resin part, 10 ... gold flash plating layer, 11 ... metal layer, DESCRIPTION OF SYMBOLS 12 ... Gold plating layer, 13 ... Printed wiring board, 14 ... Solder, 15 ... Wiring, 17 ... Nickel layer, 18 ... Palladium layer, 19, 19A, 19B ... Titanium layer, 20 ... Outer lead, 21 ... First fold Curve part, 22 ... 2nd bent part

Claims (10)

A substrate made of a metal part;
An aluminum reflective layer having a thickness of 0.02 μm or more and 5 μm or less provided on the side of the substrate on which the semiconductor light emitting element is mounted;
The aluminum reflective layer is a substrate for mounting a semiconductor light emitting element, wherein an impurity carbon concentration is 1 × 10 ¹⁴ atoms / cm ³ or more and 1 × 10 ²⁰ atoms / cm ³ or less.   The substrate for mounting a semiconductor light emitting element according to claim 1, wherein a metal layer containing titanium is provided between the base material and the aluminum reflective layer. A first metal layer made of a metal other than Ag is provided between the base material and the aluminum reflective layer;
The first metal layer is made of one type selected from palladium, gold, tin, nickel, copper-tin alloy, copper-nickel alloy, iron-nickel alloy,
The semiconductor light emitting element mounting substrate according to claim 1, wherein the aluminum reflective layer is provided on at least a part of the first metal layer.   The board | substrate for semiconductor light-emitting device mounting of Claim 1 or 2 with which the nickel layer and the palladium layer were provided in order from the said base material side between the said base material and the said aluminum reflective layer.   The semiconductor light-emitting element mounting substrate according to claim 4, wherein a gold flash plating layer is provided between the palladium layer and the aluminum reflective layer. A base material made of copper or a copper alloy;
An aluminum reflective layer having a thickness of 0.02 μm or more and 5 μm or less provided on the side of the substrate on which the semiconductor light emitting element is mounted;
A metal layer containing titanium provided between the base material and the aluminum reflective layer;
A substrate for mounting a semiconductor light-emitting element. A substrate made of a metal part;
An aluminum reflective layer having a thickness of 0.02 μm or more and 0.1 μm or less provided on the side of the substrate on which the semiconductor light emitting element is mounted;
A substrate for mounting a semiconductor light-emitting element. A substrate for mounting a semiconductor light emitting device according to any one of claims 1 to 7,
A semiconductor light emitting device mounted on the semiconductor light emitting device mounting substrate;
Surrounding part of the semiconductor light emitting element mounting substrate, the semiconductor light emitting element has a recess formed on an inclined surface or a vertical surface that moves away from the semiconductor light emitting element as the distance from the semiconductor light emitting element mounting substrate increases. An envelope part,
A semiconductor light emitting device comprising: a light transmissive resin portion that fills the concave portion of the envelope portion and seals the semiconductor light emitting element. The semiconductor light emitting element is mounted on the aluminum reflective layer formed on the substrate,
The said base material in which the said aluminum reflective layer was formed is electrically insulated, Wire bonding or inner lead bonding is carried out to the said base material in which the said aluminum reflective layer is not formed as a terminal for electric power feeding. Semiconductor light emitting device. The main constituent material of the surface of the base material to be wire-bonded or inner-lead bonded as the power supply terminal is one or a combination selected from gold, silver, palladium, gold alloy, silver alloy, or palladium alloy. Item 9. The semiconductor light emitting device according to Item 8.

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