WO2013047876A1 - Light-emitting device - Google Patents

Abstract

The present invention provides a light-emitting device that has a positive electrode oxide film layer at at least a portion of the surface of a valve metal substrate, is provided on the positive electrode oxide film layer with an inorganic reflecting layer having inorganic particles and an inorganic binder, is provided on the inorganic reflecting layer with a metal wiring layer and a light-emitting element, and has a glass material layer that contains fluorescent bodies and seals the inorganic reflecting layer, the metal wiring layer, and the light-emitting element, wherein the entirety of the light-emitting device is configured from inorganic materials, the adhesion between the glass material layer containing fluorescent bodies and the inorganic reflecting layer is high, and there is little degradation over time even if light emission is caused over the long term at a high current.

Description

Light emitting device

The present invention relates to a light emitting device, and more particularly to a light emitting device that emits light from a light emitting element such as a light emitting diode (LED).

Conventionally known light emitting devices have various problems because a protective layer (mold member) for protecting the light emitting diodes is formed of resin. FIG. 3 is a schematic cross-sectional view of a conventional light emitting device. A light-emitting device 300 shown in FIG. 3 has a white resist layer 130 having a resin matrix on the surface of a base 110 such as metal or white alumina as an insulating layer, and the metal wiring layer 5 and the light-emitting element 10 are formed on the surface of the insulating layer. It has. The pad electrode 18 provided on the metal wiring layer 5 and the light emitting element 10 are electrically connected by a bonding wire 19. Since the sealing resin layer 170 made of a resin having a phosphor is used as the sealing layer of the light emitting element 10 or the like, when the light emitting device 300 is used over time, moisture enters from the sealing resin layer 170 to operate the light emitting diode. There is a problem of inhibiting. Further, when the light from the light emitting diode contains ultraviolet light, the sealing resin layer 170 is discolored by receiving the ultraviolet light, and the light transmission property from the light emitting diode is lowered, thereby effectively reducing the performance of the light emitting diode. There is a problem of lowering.

In order to improve such a problem of the resin-made light-emitting diode protective layer, Patent Document 1 discloses that phosphor powder is mixed in the glass layer, and the glass layer is provided in contact with the wiring conductor. It is in the resin. A technology is described in which light emitted from a semiconductor light-emitting element is converted to a desired light emission wavelength by a fluorescent substance in a glass layer and is emitted to the outside through a glass layer surrounding the semiconductor light-emitting element and a transparent sealing resin on the glass layer.

Patent Document 2 describes an LED light-emitting device in which an LED element is mounted on a white alumina substrate and an insulating film formed of sol-gel glass is provided so as to surround or surround the bottom surface, side surface, or top surface of the LED element. Has been. It is described that the insulating film has substantially the same thermal expansion coefficient as that of the LED element, so that the non-lighting of the LED element and the decrease in luminous intensity can be avoided.

Japanese Patent Laid-Open No. 11-251640 JP 2006-13324 A

However, in recent years, there has been a demand for light emitting elements to emit light with a large current, and in a light emitting device including a resin sealing layer having a phosphor, when a large current is passed, the vicinity of the light emitting element becomes high temperature and the resin deteriorates with time. , The luminous efficiency becomes worse.
In the technique described in Patent Document 1, there is a problem of breakage during processing and deterioration with time due to insufficient adhesion between the wiring conductor and the glass layer.
In the technique described in Patent Document 2, white alumina produced by sintering alumina at a high temperature is expensive. There is a problem in the adhesion between the white alumina substrate and the insulating film formed of Al alkoxide, and the substrate may be damaged when it is processed. In addition, since the alumina substrate has a low light reflectance, it is necessary to separately provide an Ag reflecting layer or the like, and there is a problem that processing such as screwing is difficult and screwing mounting is difficult.

In order to solve the above-mentioned problems of the prior art, the present inventor is a light emitting device formed entirely of an inorganic material or an inorganic material (hereinafter referred to as inorganic material), and an anodized film layer is formed on the surface of a valve metal substrate. By using a glass material layer that includes an inorganic reflective layer and seals the inorganic reflective layer, the metal wiring layer, and the light emitting element, the adhesion of each layer is high, and deterioration over time is possible even if light is emitted for a long time with a large current. As a result, the inventors have found that a light emitting device with a small amount of light can be obtained, and have reached the present invention.
That is, the present invention provides the following.

(1) An anodized film layer is provided on at least a part of the surface of the valve metal substrate, and an inorganic reflective layer having inorganic particles and an inorganic binder is provided on the anodized film layer.
A metal wiring layer and a light emitting element are provided on the inorganic reflective layer,
A light-emitting device having a glass material layer containing a phosphor that seals the inorganic reflective layer, the metal wiring layer, and the light-emitting element.
(2) The light emitting device according to (1), wherein the glass material layer is obtained by applying and curing a material made of a metal alkoxide, a ceramic precursor polymer, or water glass.
(3) The light emitting device according to (1) or (2), wherein the inorganic binder is at least one selected from the group consisting of sodium silicate, aluminum phosphate, and aluminum chloride.
(4) The light emitting device according to any one of (1) to (3), wherein the inorganic particles have a refractive index of 1.5 to 1.8 and an average particle diameter of 0.1 μm to 5 μm.
(5) The light emitting device according to any one of (1) to (4), wherein the inorganic reflective layer is obtained by low-temperature baking at a temperature of 100 ° C. to 300 ° C.
(6) The light-emitting device according to any one of (1) to (5), wherein the inorganic reflective layer is further surface-modified.
(7) The valve metal substrate is at least one metal plate selected from the group consisting of aluminum, tantalum, niobium, titanium, hafnium, zirconium, zinc, tungsten, bismuth and antimony (1) to (6 The light emitting device according to any one of the above.
(8) The light-emitting device according to any one of (1) to (7), wherein the light-emitting device has a through-hole penetrating the valve metal substrate and the inorganic reflective layer, and the light-emitting element is flip-chip mounted.
(9) The light-emitting device according to any one of (1) to (8), wherein two or more kinds of the inorganic particles are included in the inorganic reflective layer.
(10) The light emitting device according to any one of (1) to (9), wherein the light emitting element is a light emitting diode (LED), and the light emitting device is a light emitting diode device.
(11) Anodizing at least part of the surface of the valve metal substrate;
An inorganic reflective layer is formed on the obtained anodized film layer,
A metal wiring layer is provided on the inorganic reflective layer, a light emitting element is mounted, the mounted light emitting element is electrically connected to an external electrode,
A method of manufacturing a light emitting device, wherein the inorganic reflective layer, the metal wiring layer, and the light emitting element are sealed with a glass material containing a phosphor.
(12) The method for manufacturing a light emitting device according to (11), wherein the valve metal substrate is machined before the anodizing step to form a through hole, and the light emitting element is flip-chip mounted.
(13) The light emitting device according to (12), wherein the inorganic reflective layer, the metal wiring layer, and the light emitting element are sealed with a glass material containing the phosphor to produce a light emitting device, and then separated into a desired unit of the light emitting device. Device manufacturing method.

The present invention is a light emitting device that is entirely composed of an inorganic material, has high adhesion between an inorganic reflective layer and a glass material layer containing a phosphor, and has little deterioration over time even when light is emitted for a long time with a large current.

It is a cross-sectional schematic diagram explaining an example of the suitable embodiment of the light-emitting device of this invention. It is a cross-sectional schematic diagram explaining an example of another suitable embodiment of the light-emitting device of this invention. It is a cross-sectional schematic diagram explaining the light-emitting device of a prior art. It is a schematic diagram which shows another example of the light-emitting device of this invention, FIG. 4 (A) shows sectional drawing, FIG.4 (B) shows a partially expanded view.

[Light emitting device]
Hereinafter, the light-emitting device of the present invention will be described in detail.
The light-emitting device of the present invention has an anodized film layer on at least a part of the surface of the valve metal substrate, and an inorganic reflective layer having inorganic particles and an inorganic binder on the surface thereof.
A metal wiring layer and a light emitting element are provided on the inorganic reflective layer,
A light-emitting device having a glass material layer containing a phosphor that seals the inorganic reflective layer, the metal wiring layer, and the light-emitting element.
Next, the structure of the light-emitting device of the present invention will be described with reference to FIG.

FIG. 1 is a schematic cross-sectional view showing an example of a preferred embodiment of the light emitting device of the present invention.
As shown in FIG. 1, the light emitting device 30 of the present invention has an anodized film layer 2 on at least a part of the surface of a valve metal substrate 1, and an inorganic reflection having inorganic particles and an inorganic binder on the surface. With layer 3;
A metal wiring layer 5 and a light emitting element 10 are provided on the inorganic reflective layer 3,
The light emitting device includes a glass material layer 7 including a phosphor 6 that seals the inorganic reflective layer 3, the metal wiring layer 5, and the light emitting element 10. A pad electrode 18 is provided on the metal wiring layer 5 and is electrically connected to the light emitting element 10 by wire bonding 19.
Since the valve metal substrate 1 has the anodized film layer 2 on at least a part of its surface, the insulating property of the substrate is improved, and the adhesion between the inorganic reflective layer 5 and the valve metal substrate 1 is also improved.

FIG. 2 is a schematic cross-sectional view showing another example of a preferred embodiment of the light emitting device of the present invention.
In the example of the light emitting device 32 shown in FIG. 2, the inorganic reflective layer 3 having inorganic particles and an inorganic binder is provided on at least a part of the surface of the valve metal substrate 1. Furthermore, through holes (hereinafter sometimes referred to as through holes) 20 and 21 penetrating the valve metal substrate 1 and the inorganic reflective layer 3 are provided. A metal wiring layer 5 is provided on the inorganic reflective layer 3.
When the anodized film layer 2 is provided between the surface of the valve metal substrate 1 and the inorganic reflective layer, and the anodized film layer 2 is also provided on the inner surface of the through hole 20.21, the through hole serves as a conductive path. Since the insulating property of a through-hole is high when using, it is preferable. When the insulating properties of the through holes 20 and 21 are sufficient, the metal wiring layer 5 may be provided on at least a part of the through holes 20 and 21. When the metal wiring layer is provided on the through hole, when the through hole is filled with a conductive metal and used as a conductive path, the connection path is electrically connected between the metal wiring layer 5 and the conductive path. This is preferable because it can be shortened.
If the light-emitting device has a through hole, the light-emitting element 10 is flip-chip mounted (surface mounted) directly on the metal wiring layer 5 through the conductive bumps 17. Since the light emitting device 32 having this configuration does not use a bonding wire, there is no possibility that the bonding wire is peeled off or disconnected.
The inorganic reflection layer 3, the metal wiring layer 5, and the light emitting element 10 are sealed with a glass material layer 7 including a phosphor 6.
The surface of the valve metal substrate 1 opposite to the side on which the light emitting element 10 is mounted is penetrated by the through holes 20 and 21, and the electrode plate 15 is provided via an insulating layer such as the anodized film layer 2. It is done. In the example of the light emitting device 32 shown in FIG. 2, the electrode plate 15 and the light emitting element 10 can be electrically connected via the metal wiring layer 5 using the through hole 21 as a conductive path.

[Inorganic reflective layer]
The inorganic reflective layer of the present invention is an aggregate composed of a large number of inorganic particles that contain inorganic particles and an inorganic binder, which will be described later, and that are partially bound to each other by the inorganic binder. The inorganic reflective layer is not particularly limited as long as the constituent material is an inorganic component. It is preferable not to include an organic component. If the inorganic reflective layer is composed only of an inorganic material, it has high heat resistance and light resistance and is resistant to aging.

In the present invention, the thickness of the inorganic reflective layer is preferably 10 μm or more, more preferably 10 to 50 μm, and even more preferably 20 to 40 μm.
When the thickness of the inorganic reflective layer is 10 μm or more, the insulating properties are good. Moreover, it is preferable that the thickness of the inorganic reflective layer is 50 μm or less because flexibility is maintained and processability, handling, and the like are improved.

The inorganic reflective layer is provided on an anodic oxide film described later on the valve metal substrate. Specifically, the anodized film layer 2 and the inorganic reflective layer 3 may be provided on a part of the valve metal substrate 1, or only the anodized film layer 2 may be present. This is because the position where the insulating layer, which is an anodized film layer, and the inorganic reflective layer are required differs depending on the shape of the element to be mounted and the position of the wiring, and it is necessary to arrange them in various designs.

(Inorganic binder)
In the inorganic reflective layer of the present invention, it is preferable to use aluminum phosphate, aluminum chloride, or sodium silicate as a binder which is a binder for inorganic particles. A mixture of two or more of these may be used.
The inorganic binder is a substance that forms inorganic reflection layers by bonding inorganic particles described later by low-temperature firing. The following can be illustrated in detail.
(Aluminum phosphate)
Examples of the aluminum phosphate include aluminum metaphosphate, aluminum orthophosphate, and aluminum polyphosphate.
(Aluminum chloride)
Examples of the aluminum chloride include aluminum chloride, anhydrous aluminum chloride, aluminum chloride hexahydrate, and polyaluminum chloride (a polymer of basic aluminum chloride formed by dissolving aluminum hydroxide in hydrochloric acid).
(Sodium silicate)
The above-mentioned sodium silicate is also called sodium silicate or water glass, and is generally Na ₂ SiO ₃ which is a sodium salt of metasilicate, but Na ₄ SiO ₄ , Na ₂ Si ₂ O ₅ , Na ₂ Si ₄ O ₉ or the like can also be used. The sodium salt of metasilicic acid can be obtained by melting silicon dioxide with sodium carbonate or sodium hydroxide.

(Inorganic binder precursor)
The inorganic binder can be obtained by reacting an inorganic binder precursor in the presence of water.
Inorganic binder precursors include inorganic acids such as phosphoric acid, hydrochloric acid, sulfuric acid, aluminum, and aluminum compounds such as aluminum oxide, aluminum sulfate, aluminum hydroxide, aluminum chloride, aluminum phosphate, and mixtures thereof. It is done. If neutralization of the reactant is necessary, sodium hydroxide solution is used. The aluminum compound may be produced by reacting each raw material as an inorganic binder precursor.
Of the above aluminum salts, it is preferable to add both aluminum hydroxide and aluminum chloride to the inorganic binder precursor, and the amount of aluminum chloride is 5% by mass to 10% by mass with respect to the amount of aluminum hydroxide. It is preferable that Aluminum chloride is considered to have a role of catalytically promoting the reaction between aluminum hydroxide and phosphoric acid, and the amount is preferably in the above range. In addition, when aluminum chloride and hydrochloric acid are used and the aluminum phosphate precursor is not used, aluminum chloride, which is an inorganic binder, is not colored, so that the light reflectance is high.
A phosphate compound may be used instead of or together with aluminum phosphate, and the phosphate compound is not particularly limited as long as it is insoluble in water. Specific examples include magnesium phosphate, calcium phosphate, zinc phosphate, barium phosphate, aluminum phosphate, gallium phosphate, lanthanum phosphate, titanium phosphate, and zirconium phosphate. Aluminum phosphate is preferable, and when mixed with other phosphates, 50% by mass or more is preferably aluminum phosphate.
When sodium silicate is used, it is dissolved in water, heated and adjusted to a viscosity suitable for water glass, and used as an inorganic binder precursor.
These inorganic binder precursors can be mixed and used in any combination so as to produce the desired inorganic binder.

(Inorganic particles)
In the present invention, the inorganic particles are not particularly limited, and for example, conventionally known inorganic salts such as metal oxides, metal hydroxides, carbonates, and sulfates can be used, and among them, metal oxides are used. Is preferred.
Specific examples of the inorganic particles include metal oxides such as aluminum oxide (alumina), magnesium oxide, yttrium oxide, titanium oxide, zinc oxide, silicon dioxide, and zirconium oxide; aluminum hydroxide, calcium hydroxide, Hydroxides such as magnesium hydroxide; calcium carbonate (light calcium carbonate, heavy calcium carbonate, ultrafine calcium carbonate, etc.), carbonates such as barium carbonate, magnesium carbonate, strontium carbonate; sulfates such as calcium sulfate and barium sulfate Other examples include calcium carbonate, calcite, marble, gypsum, kaolin clay, calcined clay, talc, sericite, optical glass, glass beads, and the like.
Among these, aluminum oxide, silicon dioxide, aluminum hydroxide, and barium sulfate are preferable because of their good affinity with the inorganic binder described later.

The inorganic particles used in a suitable inorganic reflective layer have a refractive index of 1.5 or more and 1.8 or less, preferably 1.55 or more and 1.75 or less. When the refractive index is within this range, the obtained inorganic reflective layer has a high reflectance. This reason is considered to be due to a difference in reflectance from air.
The average particle diameter of the inorganic particles is preferably 0.1 μm or more and 5 μm or less. More preferably, it is 0.5-2 μm, and still more preferably 0.5-1.5 μm. When inorganic particles having an average particle diameter in this range are used, it is considered that appropriate voids can be secured between the particles and adhesion with the anodized film layer can be obtained. When the average particle size is 0.1 μm or more and 5 μm or less, the reflectance is excellent and the adhesion with the anodized film layer is excellent.

Here, the average particle diameter means an average value of the particle diameters of the inorganic particles. In the present invention, for example, a laser diffraction particle size distribution measuring device (laser diffraction / scattering particle size distribution measuring device, Partica LA-910). And 50% volume cumulative diameter (D50) measured using HORIBA, Ltd.
In the process of manufacturing the so-called ceramic layer by binding inorganic particles by high-temperature sintering such as 1000 ° C. or higher in the prior art, it is necessary to control the progress of high-temperature sintering in order to secure specific voids in the layer. However, the preferred inorganic reflective layer of the present invention is that the inorganic reflective layer produced using the above inorganic binder can be dried by heating at a low temperature and does not sinter at a high temperature, so the average particle size of the inorganic particles as a raw material is important. Factor.

Although it does not limit as said inorganic particle, For example, the following inorganic particles can be illustrated.
Aluminum oxide (alumina) (refractive index n = 1.65 to 1.76, hereinafter the number in parentheses is the refractive index), aluminum hydroxide (1.58 to 1.65 to 1.76), hydroxide Calcium (1.57 to 1.6), calcium carbonate (1.58), calcite (1.61), calcium carbonate (1.61), light calcium carbonate (1.59), heavy calcium carbonate (1. 56), ultrafine calcium carbonate (1.57), gypsum (1.55), calcium sulfate (1.59), marble (1.57), barium sulfate (1.64), barium carbonate (1.6) , Magnesium oxide (1.72), magnesium carbonate (1.52), magnesium hydroxide (1.58), strontium carbonate (1.52), kaolin clay (1.56), calcined clay (1.62), talc 1.57), sericite (1.57), optical glass (1.51 to 1.64), glass beads (1.51). The material of the particles to be used only needs to satisfy the refractive index in the above range, and since there is no step of sintering, various inorganic salts can be used without being limited to oxides.

Further, two or more kinds of particles or two or more kinds of particles having an average particle diameter may be mixed and used as long as the above characteristics are satisfied. By combining particles of different particle diameters or different materials, it is possible to improve the film strength and the adhesion strength with the substrate.
Furthermore, the effect of smoothing the surface by improving the properties of the coated surface can be expected.

Further, the shape of the inorganic particles is not particularly limited, and for example, spherical, polyhedral (for example, icosahedron, dodecahedron, etc.), cubic, tetrahedral, and uneven or convex protrusions on the surface. Any of a plurality of shapes (hereinafter, also referred to as “compete shape”), a plate shape, a needle shape, or the like may be used.
Among these, spherical, polyhedral, cubic, tetrahedral, and complex shapes are preferred for the reason of excellent heat insulation, and spherical is more preferred for reasons of easy availability and excellent heat insulation.

(Inorganic reflective layer)
The preferred inorganic reflective layer exemplified above is preferably 20 g / m ² to 500 g / m ^{2 in} terms of mass per unit area after heat drying. Within this range, the air gap is left in the interior, so light transmission is suppressed and the reflectance is high. By using the specific inorganic binder described above, high temperature sintering is unnecessary, and an inorganic reflective layer can be produced at a lower cost. The inorganic reflective layer is an inorganic material and is resistant to aging. Furthermore, it reacts with the anodized film of the substrate when forming the reflective layer, and it is possible to ensure adhesion with the substrate.
The amount of inorganic particles in a suitable inorganic reflective layer and the amount of at least one inorganic binder selected from the group consisting of aluminum phosphate, aluminum chloride, and sodium silicate are based on 100 parts by mass of the inorganic particles. The inorganic binder is preferably 5 to 100 parts by mass, more preferably 10 to 50 parts by mass.
A suitable inorganic reflective layer may contain other compounds in addition to the inorganic particles and the inorganic binder. Examples of other compounds include dispersants, reaction accelerators, and the like, and these and the above inorganic particles, inorganic binder precursors, reaction products of inorganic particles and inorganic binders, and the like. It is done.

<The manufacturing method of a suitable inorganic reflection layer>
The method for producing a suitable inorganic reflective layer described above is not particularly limited, but an inorganic binder and / or an inorganic binder precursor and inorganic particles are mixed as a binder liquid described below, and this mixed liquid is mixed. It is preferable to apply a predetermined amount on the anodized film layer using a coater whose film thickness can be adjusted, and then heat treatment (low temperature firing) at 100 to 300 ° C. for 10 to 60 minutes.
The coating method is not particularly limited, and various methods can be used. Examples thereof include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, and roll coating. it can.
When the aqueous dispersion of the inorganic binder precursor and the inorganic particles is adjusted with a stoichiometric composition ratio according to the reaction formula, the reaction proceeds and the viscosity of the liquid increases rapidly. In order to avoid such a phenomenon and form an inorganic reflective layer stably, it is desirable to add some water in advance. In addition, it is not desirable that phosphate groups or hydrochloric acid groups remain in the anodized film layer, which may cause corrosion of the substrate or deterioration of the LED sealing material. Therefore, it is desirable to prescribe a slightly excessive amount of components other than phosphoric acid or hydrochloric acid with respect to the stoichiometric ratio.
The formation of aluminum phosphate, aluminum chloride, or sodium silicate in the heat-dried film can be easily confirmed by analyzing the film surface with an infrared spectrophotometer.

It is also possible to adjust the inorganic reflective layer to two or more layers by adjusting two or more kinds of binder liquids having different compositions and sequentially applying the binder liquid onto the anodized film. By combining two or more inorganic reflective layers, it is possible to improve the strength of the inorganic reflective layer and the strength of adhesion to the substrate. Furthermore, the effect of smoothing the surface by improving the properties of the coated surface can be expected.

(Low temperature firing)
By the above-mentioned low-temperature firing, the reaction proceeds and the inorganic particles are bound by an inorganic binder that is generated by the reaction.
The low-temperature firing temperature is 100 ° C. to 300 ° C., preferably 150 ° C. to 300 ° C., and more preferably 180 ° C. to 250 ° C.
If it is less than 100 ° C., moisture removal is not suitable, and if it exceeds 300 ° C., the strength of the aluminum substrate changes, which is not desirable. In addition, a temperature of 150 ° C. or higher is desirable for proceeding and binding the reaction between the inorganic binder precursors, and 180 ° C. or higher for completely removing the adsorbed water remaining in the obtained inorganic binder. It is desirable that When the treatment is performed for a long time at a temperature exceeding 250 ° C., the strength of the valve metal base material is changed.
The firing time is 10 minutes to 60 minutes, more preferably 20 minutes to 40 minutes. In a short time, the progress of the reaction is insufficient, and when the time is long, the strength of the valve metal substrate, particularly the aluminum metal substrate, changes in relation to the firing temperature. If it is more than 60 minutes, it is not desirable in terms of production cost. For this reason, the firing time is most preferably 20 minutes to 40 minutes.
Since the binder liquid is a liquid containing water, a drying step may be performed after the coating and before the low-temperature baking treatment. Drying is performed at a temperature of 100 ° C. or lower which does not cause a formation reaction of an inorganic binder such as aluminum phosphate or a binding reaction of inorganic particles.

The obtained inorganic reflective layer may be subjected to a surface treatment such as a hydrophilization treatment, a heating steam treatment, or a polydimethylsiloxane modification treatment. It is preferable to perform any of these treatments because adhesion to a metal wiring layer and a glass material layer described later is enhanced.

(Hydrophilic treatment)
In the present invention, a suitable inorganic reflective layer may be subjected to a hydrophilic treatment after the low-temperature baking treatment.
Specific examples of the hydrophilic treatment method include a method of immersing in an aqueous solution of an alkali metal silicate.

Here, the hydrophilization treatment using an aqueous solution of alkali metal silicate is performed according to the method and procedure described in US Pat. No. 2,714,066 and US Pat. No. 3,181,461. It can be carried out.

Specific examples of the alkali metal silicate include sodium silicate, potassium silicate, and lithium silicate.
The aqueous solution of the alkali metal silicate may further contain sodium hydroxide, potassium hydroxide, lithium hydroxide and the like.

Furthermore, the aqueous solution of the alkali metal silicate may further contain an alkaline earth metal salt or a Group 4 (Group IVA) metal salt.
Here, specific examples of the alkaline earth metal salt include nitrates such as calcium nitrate, strontium nitrate, magnesium nitrate, and barium nitrate; sulfates; hydrochlorides; phosphates; acetates; Borate; and the like.
Specific examples of the Group 4 (Group IVA) metal salt include, for example, titanium tetrachloride, titanium trichloride, potassium fluoride titanium, potassium oxalate, titanium sulfate, titanium tetraiodide, and chloride oxidation. Zirconium, zirconium dioxide, zirconium oxychloride, zirconium tetrachloride and the like can be mentioned.
These alkaline earth metal salts and Group 4 (Group IVA) metal salts may be used alone or in combination of two or more.
In the hydrophilization treatment, when an aqueous solution of the alkali metal silicate is used, the aqueous solution of the alkali metal silicate is a ratio of silicon oxide SiO ₂ and alkali metal oxide M ₂ O, which are components of the silicate ( In general, the protective film thickness can be adjusted by the concentration of [SiO ₂ ] / [M ₂ O]) and the concentration.
Here, as M, sodium and potassium are particularly preferably used.
The molar ratio of [SiO ₂ ] / [M ₂ O] is preferably 0.1 to 5.0, more preferably 0.5 to 3.0. Further, the content of SiO ₂ is preferably 0.1 to 20% by mass, and more preferably 0.5 to 10% by mass.

The temperature of the aqueous alkali metal silicate solution is preferably 1 to 70 ° C., more preferably 2 to 50 ° C., and still more preferably 3 to 35 ° C.
Further, the treatment time in the case of using the alkali metal silicate aqueous solution is preferably 5 seconds to 90 minutes, more preferably 8 seconds to 60 minutes, and preferably 12 seconds to 30 minutes. Further preferred.

(Heated steam treatment)
In the present invention, the steam treatment may be performed after the low-temperature firing treatment. The heated steam treatment is a treatment including boiling water treatment, hot water treatment, steam treatment, and the like based on temperature and pressure conditions.
The water used may be any of ion exchange water, distilled water, natural water, tap water, etc., but ion exchange water and distilled water are preferred. Further, as an accelerator for these waters and a sequestering agent for metal ions in the water, an organic solvent, an amine compound, an organic acid, phosphorus or boron oxyacid salt, or the like may be used alone or in combination. The water used may also contain ions of alkali metal alkaline earth metals such as lithium, sodium or magnesium.
The surface treatment is preferably carried out continuously using water vapor, and the temperature for the water vapor treatment is about 80 ° C. to 200 ° C., preferably about 90 ° C. to 120 ° C. The treatment time is 3 seconds to 30 minutes, preferably 5 seconds to 10 minutes. The hydrogen ion concentration is suitably about 2 to 11, preferably about 3 to 10. About 1 to 15 kg / cm ² (absolute pressure) is appropriate as the pressure when treating with pressurized steam, and preferably about 1 to 5 kg / cm ² is preferred.
Industrially, the temperature of water in a water tank provided in the processing chamber is heated, whereby the temperature in the processing chamber is set to 80 ° C. or more and 105 ° C. or less, and the processing chamber pressure is maintained at −50 to 300 mmAq with respect to normal pressure. Alternatively, a method may be used in which the inorganic reflective layer requiring heating steam treatment is passed through the state.

(Modification treatment of polydimethylsiloxane)
A light transmissive flexible film may be formed on the surface of the inorganic reflective layer using one or a mixture of polyorganosiloxanes such as polydimethylsiloxane. The polyorganosiloxane is diluted with an aqueous solution or an organic solvent, and applied onto the inorganic reflective layer, sprayed, or immersed in the liquid. When the inorganic reflective layer is modified with polydimethylsiloxane, the adhesiveness with the glass material layer provided thereon is increased.

[Metal wiring layer]
The metal wiring layer is formed on at least a part of the surface of the inorganic reflective layer of the light emitting device of the present invention.
Here, “formed on at least a part of the surface of the inorganic reflective layer” means that the metal wiring layer is formed on the inorganic reflective layer or on the inorganic reflective layer and in the inorganic reflective layer. This includes a case where a part of the material forming the layer enters the inorganic reflective layer and the rest is formed on the inorganic reflective layer.
In this invention, since the said inorganic reflection layer is porous, the metal wiring layer formed in the surface becomes favorable [adhesiveness with an inorganic reflection layer] by an anchor effect.

The material of the metal wiring layer is not particularly limited as long as it is a material that conducts electricity (hereinafter also referred to as “metal material”). Specific examples thereof include gold (Au), silver (Ag), and copper (Cu ), Aluminum (Al), magnesium (Mg), nickel (Ni) and the like, and these may be used alone or in combination of two or more. Of these, Cu is preferably used because of its low electrical resistance.
The metal wiring layer may have a multilayer structure using these materials. For example, an embodiment in which an Ag layer, a Ni layer, and an Au layer are provided in this order from the bottom layer is preferable.

The thickness of the metal wiring layer may be a desired thickness depending on the purpose and application, but is preferably 0.5 to 1000 μm, more preferably 1 to 500 μm from the viewpoint of conduction reliability and package compactness. 5 to 250 μm is particularly preferable.
Further, when the metal wiring layer has a multilayer structure, the thickness of the lowermost layer (for example, Ag layer) is 50% or more of the total thickness of the metal wiring layer in consideration of the presence of minute voids in the receiving layer. It is preferable that it is 70 to 80%. Specifically, the thickness is preferably 10 to 50 μm, more preferably 15 to 40 μm.
Similarly, when the metal wiring layer has a multilayer structure, the thickness of the uppermost layer (for example, Au layer) is preferably 0.05 to 0.5 μm in consideration of wire bonding properties, More preferably, the thickness is ~ 0.4 μm.

<Formation of metal wiring layer>
As a method for forming the metal wiring layer, for example, a metal ink containing the metal material and a liquid component (for example, a solvent, a resin component, etc.) is pattern-printed on the receiving layer by an inkjet printing method, a screen printing method, or the like. Methods and the like.
By such a forming method, it is possible to easily form a wiring layer having a pattern on the surface of the uneven receiving layer without requiring many steps.

In addition, as other methods for forming the metal wiring layer, for example, various plating treatments such as electrolytic plating treatment, electroless plating treatment, displacement plating treatment, sputtering treatment, vapor deposition treatment, vacuum pasting treatment of metal foil, Examples include an adhesion treatment with an adhesive layer.
When the metal wiring layer has a multilayer structure, it is preferable that two or more layers are manufactured by electrolytic plating.

[Glass material layer]
The glass material layer includes a glass material and a phosphor mixed therein. The phosphor is made of a phosphor material that is transparent to the light emitted from the light emitting element and absorbs the light emitted from the light emitting element and converts it to another emission wavelength.
In a preferred aspect of the present invention, the glass material layer includes SiO ₂ including at least one of a group selected from PbO, Ga ₂ O ₃ , Bi ₂ O ₃ , CdO, ZnO, BaO, and Al ₂ O _3. or made of SiO ₂ which does not contain these substantially.

The reason for incorporating the compound selected from PbO, Ga ₂ O ₃ , Bi ₂ O ₃ , CdO, ZnO, BaO and Al ₂ O ₃ by devising the configuration of the glass material layer as described above is as follows. is there. Reflection occurs at the interface between the light emitting element and the surrounding packaging material such as a glass material layer. The ratio at which total reflection occurs increases as the difference in refractive index increases. When total reflection occurs, the light is bounced inside, and the light extraction efficiency is reduced. Therefore, in order to efficiently transmit light from the light emitter to the air, it is desirable to reduce reflection at the interface through which the light from the light emitter passes as much as possible. For this purpose, it is necessary to reduce the difference in refractive index between the interfaces. In the case where the light-emitting device is composed of two layers of a light-emitting element and a glass material layer, there are two interfaces, ie, a light-emitting element and a glass material layer, and a glass material layer and an air layer. In order to reduce the amount of reflection, it is desirable to reduce the difference in refractive index between the two interfaces.

The glass material layer is formed by using a coating glass material made of a metal alkoxide (tetramethoxysilane, tetraethoxysilane, etc.) as a starting material or a coating precursor glass material made of a ceramic precursor polymer (perhydropolysilazane, etc.). It is preferable. A coating type glass material starting from a metal alkoxide (tetramethoxysilane, tetraethoxysilane, etc.) is more preferred. These coating type glass materials can be fired at around 150 ° C., and a glass material layer can be formed in a low temperature region. These coating-type glass materials are usually liquid, but when heated in air or in an oxygen atmosphere, the SiO ₂ (silicon oxide) siloxane bond is mainly formed by decomposition and scattering of components or absorption of oxygen and moisture. A transparent solid glass material layer was produced.
Moreover, you may use the water glass which has sodium silicate etc. as a main component. A glass material layer can be easily formed by baking viscous liquid water glass as a coating-type glass material.
Aiming at ceramic powders such as silica, titanium oxide, alumina, and ultrafine particulate anhydrous silica as a scattering agent, binder, and anti-settling agent, as well as phosphors, on coating glass materials consisting of coating glass materials or ceramic precursor polymers Appropriate amount may be mixed according to.
If these glass materials are mixed with a phosphor made of a phosphor material and applied to the periphery of an inorganic reflective layer having a metal wiring layer, a glass material layer having the following characteristics in addition to the light conversion function is formed. Can do.

[1] Excellent moisture resistance, no moisture permeation into the interior, and suppresses deterioration of the light emitting device and the phosphor.
[2] Since the ion barrier effect for preventing penetration of harmful ions is high, the deterioration of the light emitting element due to harmful ions from the outside of the light emitting device or from the phosphor material is suppressed.
[3] Excellent heat resistance and UV resistance, does not cause yellowing or coloration under high temperature environment or UV light emission, and does not attenuate light emission of the light emitting element.
[4] Since the silicon atoms in the glass are firmly bonded to the oxygen atoms of the metal or ceramic surface oxide layer, the adhesion to the light emitting element, the metal wiring layer or the inorganic reflective layer is good.

As described above, by using the glass material layer, various weak points of the conventional light-emitting diode device can be overcome, and a light-emitting device having a wavelength conversion function by a phosphor that is inexpensive and highly reliable can be obtained.

(Phosphor)
For example, in order to manufacture a white light emitting device, a GaN blue light emitting diode chip having an emission wavelength peak of about 440 nm to about 470 nm is used as a light emitting element, and an active material is used as a material constituting the phosphor. YAG (yttrium, aluminum, garnet, chemical formula Y ₃ Al ₅ O ₁₂ , excitation wavelength peak of about 450 nm, emission wavelength peak of about 540 nm) added with about 6 mol% of Ce (cerium) as an agent is used.
When an appropriate amount of an appropriate additive is added at the time of manufacturing a phosphor made of a YAG fluorescent material and the crystal structure is partially changed to shift the emission wavelength distribution, the emission color of the light emitting diode device (20) is further adjusted to a different color tone. be able to. For example, Ga (gallium) or Lu (lutetium) can be added to shift to the short wavelength side, and Gd (gadolinium) can be added to shift to the long wavelength side.
It is also possible to mix a light-absorbing substance such as a dye or a pigment into the glass material layer so as to absorb a part of the light emission wavelength of the light-emitting diode chip or the phosphor and adjust the light emission color of the light-emitting diode device.

For example, fluorescence of Y ₂ SiO ₅ activated by Ce and Tb (terbium) activated with a GaN-based light-emitting diode chip that generates ultraviolet light having an emission peak wavelength of about 360 nm to 380 nm and an excitation peak wavelength of about 360 nm and an emission peak wavelength of about 543 nm. When a phosphor made of a material is used, a green light emitting diode device having a very sharp light emission distribution with a half width of about 12 nm can be obtained.
The phosphor used may be any phosphor. For example, a phosphor having desired characteristics is selected from phosphors such as calcium halophosphate, calcium phosphate, silicate, aluminate, and tungstate. You can choose.

As said fluorescent substance, the thing of the following compositions can be used, for example.
As a phosphor for red light emission that converts short-wavelength light such as ultraviolet light into red visible light, M ₂ O ₂ S: Eu (M is any one of La, Gd, and Y), 0.5 MgF _2. 3.5 MgO · GeO ₂ : Mn, 2MgO · 2LiO ₂ · Sb ₂ O ₃ : Mn, Y (P, V) O ₄ : Eu, YVO ₄ : Eu, (SrMg) ₃ (PO ₄ ): Sn, Y ₂ There are O ₃ : Eu, CaSiO ₃ : Pb, Mn, and the like.
Further, as a phosphor for green emission for converting the short-wavelength light such as ultraviolet light to green visible _{light, BaMg 2 Al 16 O 27:} Eu, Mn, Zn 2 SiO 4: Mn, (Ce, Tb, Mn) MgAl ₁₁ O ₁₉ , LaPO ₄ : Ce, Tb, (Ce, Tb) MgAl ₁₁ O ₁₉ , Y ₂ SiO ₅ : Ce, Tb, ZnS: Cu, Al, ZnS: Cu, Au, Al, (Zn, Cd) S _{: Cu, Al, SrAl 2 O} 4: Eu, SrAl 2 O 4: Eu, Dy, Sr 4 Al 14 O 25: Eu, Dy, Y 3 Al 5 O 12: Tb, Y 3 (Al, Ga) 5 O ₁₂ : Tb, Y ₃ Al ₅ O ₁₂ : Ce, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, and the like.
Further, as a phosphor for blue light emission that converts short wavelength light such as ultraviolet light into blue visible light, (SrCaBa) ₅ (PO ₄ ) ₃ Cl: Eu, BaMg ₂ Al ₁₆ O ₂₇ : Eu, (SrMg) ₂ P ₂ O ₇ : Eu, Sr ₂ P ₂ O ₇ : Eu, Sr ₂ P ₂ O ₇ : Sn, Sr ₅ (PO ₄ ) ₃ Cl: Eu, BaMg ₂ Al ₁₆ O ₂₇ : Eu, CaWO ₄ , CaWO ₄ : Pb, ZnS: Ag, Cl , ZnS: Ag, Al, (Sr, Ca, Mg) 10 (PO 4) 6 Cl 2: there is Eu and the like.
By appropriately selecting and mixing the phosphors for red light emission, green light emission, and blue light emission, various colors can be developed.
In addition, when white light is obtained using an LED chip that emits blue visible light, Y ₃ Al is used as a phosphor for yellow light emission that converts light emitted from the LED chip into yellow visible light as a complementary color. ₅ O ₁₂ : Ce, YBO ₃ : Ce, BaMgAl ₁₀ O ₁₇ : Eu, Mn, (Sr, Ca, Ba) (Al, Ga) ₂ S ₄ : Eu, Ba ₂ SiO ₄ : Eu, (Sr, Ba) ₂ SiO ₄ : Eu, SiAlON: Eu and the like.

[Valve metal substrate]
Specific examples of the valve metal include aluminum, tantalum, niobium, titanium, hafnium, zirconium, zinc, tungsten, bismuth, and antimony.
The anodized film layer of the valve metal is an insulating film having high electrical resistance (about 10 ¹⁴ Ω · cm) and high heat resistance.
Of these, an anodic oxide film layer of aluminum is preferable because it has good dimensional stability and is relatively inexpensive.
The valve metal substrate may be a single plate used for the reflective substrate of the present invention.
If necessary, the valve metal substrate is laminated on another metal plate such as a steel plate, a glass plate, a ceramic plate, a resin plate or the like and used for the reflective substrate of the present invention. In order to form an anodized film and ensure insulation, the bubble metal substrate only needs to have a plate-like portion having a thickness of 10 μm or more. When another plate material and a valve metal base material are laminated and used, a laminated plate of a steel plate or metal plate that is flexible and has high heat resistance is preferable.

(Aluminum plate)
A known aluminum plate can be used for the production of the reflective substrate of the present invention. The aluminum plate used in the present invention is a metal whose main component is dimensionally stable aluminum, and is made of aluminum or an aluminum alloy. In addition to a pure aluminum plate, an alloy plate containing aluminum as a main component and containing a trace amount of foreign elements can also be used.

In this specification, various substrates made of the above-described aluminum or aluminum alloy are collectively referred to as an aluminum plate. The foreign elements that may be contained in the aluminum alloy include silicon, iron, copper, manganese, magnesium, chromium, zinc, bismuth, nickel, titanium, etc., and the content of foreign elements in the alloy is 10% by mass or less. Is preferred.

Thus, the composition of the aluminum plate used in the present invention is not specified, and the purity of aluminum is not particularly limited, but 1000 series, 3000 series, and 5000 series alloys that are usually used as plate materials are used. it can. However, when used as a reflective substrate for a light emitting device, it is required to have excellent withstand voltage, and it is desirable to reduce particles such as intermetallic compounds in the material as much as possible. If it cannot be avoided under heat treatment conditions, it is also useful to use high purity aluminum of 99.9% or more.
Specifically, conventionally known materials described in Aluminum Handbook 4th edition (1990, published by Light Metal Association), for example, JIS A1050, JIS A1100, JIS A1070, JIS A3004 containing Mn, international registered alloy 3103A, etc. Al-Mn aluminum plates can be used as appropriate. For the purpose of increasing the tensile strength, an Al—Mg alloy or an Al—Mn—Mg alloy (JIS A3005) in which 0.1% by mass or more of magnesium is added to these aluminum alloys can also be used. Furthermore, an Al—Zr alloy or an Al—Si alloy containing Zr or Si can also be used. Furthermore, an Al—Mg—Si based alloy can also be used.

Regarding Al—Mg alloys, Al—Mn alloys, Al—Mn—Mg alloys, Al—Zr alloys, and Al—Mg—Si alloys, paragraphs [0034] to [0038] of International Publication No. WO2010 / 150810. Is described in the publication.

Regarding the method for producing an aluminum alloy into a plate material, DC casting method, continuous casting method, crystal structure of the surface of the aluminum plate, and intermetallic compound of the aluminum plate, paragraphs [0039] to [0050] of International Publication WO2010 / 150810 Are listed.

In the present invention, an aluminum plate as shown above can be used by roughening it by forming irregularities by laminating rolling, transferring or the like in its final rolling step or the like. If the surface of the substrate is roughened in advance, the adhesion between the inorganic reflective layer formed on the substrate and the substrate can be improved after the anodic oxide film layer is formed. Other roughening treatment methods will be described later.

The aluminum plate used in the present invention may be an aluminum web or a sheet-like sheet.

[Method for producing substrate for light-emitting device used in light-emitting device of the present invention using Al plate]
Below, a suitable example of the manufacturing method of the board | substrate for light-emitting devices used suitably for the light-emitting device of this invention which has an anodic oxide film and an inorganic reflection layer on the aluminum plate surface is demonstrated. A metal wiring layer is provided on a substrate to be manufactured below, a light emitting element is mounted, and sealed with a glass material layer containing a phosphor as described above.
<1. Roughening>
An anodized film layer may be formed by directly anodizing an aluminum plate that has been subjected to alkali degreasing when the substrate is manufactured. Further, if the aluminum surface is roughened in advance and anodized, the adhesion between the anodized film layer and the aluminum plate can be improved, and the adhesion of the inorganic reflective layer provided thereon can also be improved. it can. Roughening treatment is a method of performing mechanical roughening treatment on an aluminum plate, alkali etching treatment, desmutting treatment with acid, and electrochemical roughening treatment using an electrolytic solution, and mechanical roughening treatment on an aluminum plate. Treatment, alkali etching treatment, desmutting treatment with acid and electrochemical surface roughening treatment using different electrolytes multiple times, alkali etching treatment on aluminum plate, desmutting treatment with acid and electrochemical using electrolyte solution Examples include a method of sequentially performing a surface roughening treatment, a method of applying an alkali etching treatment to an aluminum plate, a desmutting treatment with an acid, and an electrochemical surface roughening treatment using different electrolytes a plurality of times, but the present invention is not limited thereto. Not. In these methods, after the electrochemical roughening treatment, an alkali etching treatment and an acid desmutting treatment may be further performed.

Among them, although depending on the conditions of other treatments (alkali etching treatment, etc.), in order to form a surface shape on which a large wave structure, a medium wave structure and a small wave structure are superimposed, a mechanical surface roughening treatment and nitric acid are mainly used. Preferred examples include a method of sequentially performing an electrochemical surface roughening treatment using an electrolytic solution and an electrochemical surface roughening treatment using an electrolytic solution mainly composed of hydrochloric acid. In addition, in order to form a surface shape in which a large wave structure and a small wave structure are superimposed, an electrolytic solution mainly composed of hydrochloric acid is used, and only an electrochemical surface roughening process is performed in which the total amount of electricity involved in the anode reaction is increased. Are preferable.
Details of each surface roughening treatment are described in paragraphs [0055] to [0083] of International Publication WO2010 / 150810.

<Processing to form through holes>
In the light emitting device of the present invention, when mounting a light emitting element, a through hole (through hole) processing for providing a conductive path as appropriate, and a routing processing for forming a chip assuming the final product (to the final product) Processing for individualization) can also be performed. Through-hole processing is drilling to a required part. A conventionally well-known method can be employ | adopted for the process of a through hole, For example, a drill process, a laser process, the punching process by a metal mold | die, etc. can be used. The shape of the through-hole to be processed is not particularly limited as long as it is the length between a plurality of layers that require wiring, and the cross-section has a size / shape that can be secured by placing the necessary wiring therein. Considering the final chip size and the formation of reliable wiring, it is preferable that the shape is circular, and the size is preferably 0.01 mmφ to 2 mmφ, more preferably 0.05 mmφ to 1 mmφ, and 0.1 mmφ. Particularly preferred is ˜0.8 mmφ.

(Routing processing)
The routing process is an individual separation process that separates into the size of the reflective substrate for light emitting elements (hereinafter referred to as a chip) that is individualized in the final product, or a process that makes it easy to separate into chips in advance. It is also called one-side processing. A cutting device such as an inner saw, a slicer, or a dicer can be used. The routing process includes a process of making a notch penetrating in the thickness direction of the substrate with a device called a router or making a notch so as not to cut in the thickness direction using a dicer.
Since the light emitting device of the present invention does not include a resin layer, it can be separated into pieces by a dicing device at the final stage. If the resin layer is contained, the resin layer may be peeled off due to processing strain when it is singulated at the final stage. The light emitting device of the present invention does not need to be subjected to routing processing or the like in advance.

<Baking treatment>
The tensile strength (hereinafter referred to as tensile strength) in the tensile test (tensile speed: 2 mm / min) of the aluminum plate in the routing processing and through-hole processing described above according to JISZ2241 indicates that the substrate is a soft substrate such as 100 MPa or less. When the reflective substrate for a light emitting element of the present invention is manufactured, it is desirable to fire the aluminum plate after the machining such as routing and through-hole processing in order to soften the aluminum plate. Further, if firing is performed after the anodizing treatment, cracks and the like due to the difference in thermal expansion coefficient between the aluminum and the coating may occur, which is not desirable. Therefore, it is desirable to perform a baking treatment for adjusting the strength of the aluminum plate after the machining and before the anodizing treatment. The baking treatment after the machining and before the anodizing treatment is preferably performed at 250 to 400 ° C. for 1 to 120 minutes. When performing the baking treatment after the anodizing treatment, the baking temperature is preferably 200 ° C. to 250 ° C., and the heat treatment is preferably performed for 60 minutes to 300 minutes.

<Anodizing treatment>
It is preferable to further anodize the aluminum plate that has been surface-treated and processed as described above. By anodizing treatment, an anodized film layer made of alumina is formed on the surface of the aluminum plate, and a porous or non-porous surface insulating layer is obtained.

The anodizing treatment can be performed by a conventional method. In this case, for example, an anodized film layer can be formed by energizing an aluminum plate as an anode in an aqueous solution having a sulfuric acid concentration of 50 to 300 g / L and an aluminum concentration of 5% by mass or less. As the solution used for the anodizing treatment, sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, amidosulfonic acid, malonic acid, citric acid, tartaric acid, boric acid, etc. alone or in combination A combination of the above can be used.

The conditions of the anodizing treatment cannot be determined unconditionally because they vary depending on the electrolyte used, but generally the electrolyte concentration is 1 to 80% by mass, the solution temperature is 5 to 70 ° C., and the current density is 0.5. It is appropriate that ˜60 A / dm ² , voltage 1˜100 V, electrolysis time 15 seconds˜50 minutes, and the anodic oxide film layer amount is adjusted to a desired amount.

When anodizing is performed in an electrolytic solution containing sulfuric acid, direct current may be applied between the aluminum plate and the counter electrode, or alternating current may be applied. When direct current is applied to the aluminum plate, the current density is preferably 1 to 60 A / dm ² , and more preferably 5 to 40 A / dm ² . In the case of continuous anodizing treatment, a low current of 5 to 10 A / dm ² is initially introduced so that so-called “burning” does not occur due to current concentration on a part of the aluminum plate. It is preferable to increase the current density to 30 to 50 A / dm ² or more as the current is passed at the density and the anodization process proceeds. When the anodizing treatment is continuously performed, it is preferable that the feeding method to the aluminum plate is performed by a liquid feeding method. The liquid power supply method is an indirect power supply method that does not use a conductor roll, and power is supplied through an electrolytic solution.

The anodized film layer may be porous or nonporous. When porous, the average pore diameter is about 5 to 1000 nm, and the average micropore density is about 1 × 10 ⁶ to 1 × 10 ¹⁰ / mm ² . It is preferable that the length (length / depth) of the center line of the micropore with respect to the depth of the micropore is 1.0 to 1.2 because the shape of the micropore is almost a straight tube.

The other details of the anodizing treatment are described in paragraphs [0091] to [0094] of International Publication No. WO2010 / 150810.

Aluminum has a very high thermal conductivity and is excellent in heat dissipation. In addition to being superior to other metals, it is possible to provide insulation by forming an anodized film layer on the surface layer.
You may anodize at least 1 surface of what was processed into the board | substrate shape which mounts LED previously, for example, a hexagonal shape and an octagonal shape. The front and back surfaces of the aluminum plate may be anodized, or the inner wall surface of the formed through hole may be anodized. After anodizing and forming the inorganic reflective layer, processing such as through holes may be performed.
The thickness of the anodized film layer is preferably 1 to 200 μm. If the thickness is less than 1 μm, the insulation is poor and the withstand voltage is lowered. On the other hand, if it exceeds 200 μm, a large amount of electric power is required for production, which is economically disadvantageous. The thickness of the anodized film layer is preferably 20 μm or more, and more preferably 40 μm or more.

<5. Formation of inorganic reflective layer>
Furthermore, the above-mentioned inorganic reflective layer is formed only on the portions where light reflection is required by various printing methods such as screen printing on a substrate that has been processed in advance so that it can be disassembled into chips or parts including a plurality of chips. Also good. If the inorganic reflective layer is formed by this method, the raw material used for the inorganic reflective layer can be saved.

(Light Emitting Device Substrate)
The substrate for a light emitting device having the inorganic reflection layer described above uses a valve metal plate alone as a valve metal base material, and when other metal plates are not used for reinforcing a core material or the like, the strength is tensile according to JISZ2241. The tensile strength (hereinafter referred to as tensile strength) in the test (tensile speed: 2 mm / min) is preferably 100 MPa or less, and more preferably 30 to 80 MPa. If it is less than this range, the strength as a substrate is not sufficient, and if it exceeds this range, the handleability when processing the substrate to form a light emitting device is poor.

[Light emitting device]
The light emitting device 32 having the through-hole shown in FIG. 2 of the present invention and mounted by flip chip preferably has the following anodized film layer.
An aluminum substrate with an anodized film having through holes formed through in the thickness direction, the front surface, the back surface and the inner wall surface of the through hole being coated with an anodized film;
An inorganic reflective layer having inorganic particles and an inorganic binder on the surface of the aluminum substrate;
A metal wiring layer and a light emitting element are provided on the inorganic reflective layer,
A glass material layer containing a phosphor that seals the inorganic reflective layer, the metal wiring layer, and the light emitting element;
A metal wiring layer provided on the back surface of the aluminum substrate, electrically connected to the light emitting element through the through hole, and provided via an anodized film;
The anodized film has micropores in the thickness direction from the surface of the anodized film.

4A and 4B are schematic views showing an example of the light-emitting device of the present invention, where FIG. 4A shows a cross-sectional view and FIG. 4B shows an enlarged view.
As shown in FIG. 4A, the light emitting device 32 of the present invention includes an aluminum plate 1 having an anodized film 2, a light emitting element 10, an inorganic reflective layer 3, and a metal wiring layer 5.
The aluminum plate 1 having the anodized film 2 has through holes 20 and 21 which are through holes formed through in the thickness direction.
Further, the aluminum plate 1 having the anodized film 2 is covered with the anodized film 2 on the front surface, the back surface, and the inner wall surface of the through hole.
In FIG. 4A, all of the insides of the through holes 20 and 21 are filled with the material forming the metal wiring layer 5, but the electrode plate 15 and the light emitting element 10 provided on the back surface of the aluminum plate. Are electrically connected through the through holes 20 and 21, the through holes may be partially connected with a metal material.

As shown in FIG. 4B, which is an enlarged view of the L portion in FIG. 4A, the anodic oxide film 2 has micropores 25 extending from the surface of the anodic oxide film 2 in the thickness direction (the direction of the aluminum plate 1). Have
The micropore 25 has a straight tubular shape in the thickness direction. Specifically, the length (length / depth) of the center line of the micropore 25 with respect to the depth of the micropore 25 is 1.0 to 1.2. It is preferably formed so as to be 1.0 to 1.05.

The aluminum plate 1 having the anodized film 2 shown in FIG. 4 (A) has the front surface, the back surface, and the inner wall surface of the through hole covered with the anodized film 2. The aluminum plate 1 is processed such as through-holes, the processed aluminum plate is anodized, and the front surface, the back surface, and the inner wall surface of the through-hole are covered with the anodized film 2. To manufacture. Thereafter, the inorganic reflective layer 3 is manufactured by a method of printing and coating with a pattern having holes of the through holes 20 and 21, but is not limited to this manufacturing method.

The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these.
The light emitting devices of Examples and Comparative Examples were manufactured by the following steps.
<1. Preparation of substrate>
As the substrate, aluminum plates (thickness 0.2 mm, 0.8 mm, 1.5 mm 1050 material, manufactured by Nippon Light Metal Co., Ltd.) were used, and the following processing was performed to prepare substrates A to B, respectively.
(1) Substrate A: Alkaline degreasing treatment was performed on the aluminum plate. Table 1 describes the metal species Al, anodized film, and “-” (none).
In the following description, “-” in the table indicates that the treatment was not performed or that no member or material was used.
(2) Substrate B: The above aluminum plate was subjected to alkali degreasing treatment and anodizing treatment. In Table 1, it describes as metal seed | species Al, an anodic oxide film, and existence.
(3) Substrate Ti: An anodizing treatment was performed under the following conditions using a metal seed titanium plate (manufactured by Soekawa Riken) and a plate thickness of 0.5 mm. In Table 1, it describes as valve metal base material Ti, an anodic oxide film, and existence.
(4) White Alumina: In Comparative Example 1, a ceramic substrate obtained by sintering alumina particles (average particle size 4.7 μm) at 1450 ° C. for 2 hours has no anodized film. Table 1 describes white alumina.

(1) Processing conditions for substrate A a. Degreasing treatment in alkaline aqueous solution An aqueous solution having a sodium hydroxide concentration of 27% by mass, an aluminum ion concentration of 6.5% by mass, and a temperature of 70 ° C. was sprayed onto an aluminum plate for 20 seconds. Thereafter, the liquid was drained with a nip roller, and further, a water washing treatment described later was performed, and then the liquid was drained with a nip roller.
The water washing treatment was carried out using an apparatus for washing with a free-falling curtain-like liquid film, and further washed with water for 5 seconds using a spray tube having a structure having spray tips with fan-shaped spreading at 80 mm intervals. .
b. Desmutting treatment in acidic aqueous solution After the degreasing treatment, desmutting treatment was performed. The acidic aqueous solution used for the desmut treatment was a 1% by mass sulfuric acid aqueous solution, which was sprayed from a spray tube at a liquid temperature of 35 ° C. for 5 seconds. Then, after performing the water washing process similarly to the case after a degreasing process, it drained with the nip roller.

(2) Processing conditions for substrate B The substrate prepared in the same manner as substrate A was used as an anode, and anodization was performed using an anodizing apparatus. As the electrolytic solution, an electrolytic solution (temperature 20 ° C.) in which aluminum sulfate was dissolved in a 70 g / L sulfuric acid aqueous solution and the aluminum ion concentration was 5 g / L was used. In the anodizing treatment, electrolysis was performed at a constant voltage so that the voltage during the anodic reaction of the aluminum plate was 25V. The final anodic oxide film layer thickness was set to 20 μm.
Thereafter, the liquid was drained by a nip roller, and further, the water was washed using a spray tube having the same structure as that used in the water washing process, and then the liquid was drained by a nip roller.
(3) Processing conditions for substrate Ti Anodization was performed using an anodizing apparatus using a 0.5 mm thick titanium plate (manufactured by Soekawa Riken) as an anode.
Here, a titanium plate previously degreased with trichlorethylene was used.
In the anodizing treatment, an aqueous solution in which 25 g / L phosphoric acid, 35 g / L sulfuric acid, and 10 g / L hydrogen peroxide water are mixed is used as an electrolyte (temperature: 20 ° C.), and the substrate is 3 A / dm ² . It was carried out until a voltage of 250 V was reached at a constant current. The thickness of the anodized film was 8 μm.
In this way, a substrate Ti having a titanium anodized film on the surface as an insulating layer was produced.

<2. Formation of through holes in substrate>
In Examples 13 and 15, through holes were processed at predetermined positions on the substrate before anodizing, and the inner surface of the through holes was anodized. In Comparative Example 1, a through-hole was processed in a white alumina substrate and the element was mounted as it was.

<3. Formation of reflective layer on substrate>
The coating liquid adjusted under the following conditions was applied by forming a predetermined pattern on the substrate with a coater capable of adjusting the coating film thickness. Then, it put into the oven heated up to the temperature of Table 1, and heat-dried for 5 minutes. The amount of the inorganic reflective layer after drying was in the range of 20 g / m ² to 500 g / m ^{2 in} the examples.

(Comparative Examples 1 to 3)
Comparative Example 1 had no inorganic reflective layer, and Comparative Example 2 had the same amount of inorganic reflective layer as the Example.
In Comparative Example 3, the inorganic reflective layer material is white filler (titanium oxide particles described below, shown as titanium oxide * 1 in Table 1) at a ratio of 60 parts by mass of silicone resin (KR510 manufactured by Shin-Etsu Silicone) 100 parts by mass. A light-emitting device was manufactured in the same manner as in Example 1 except that the mixture was changed to the one obtained by mixing the above.

(Preparation of coating liquid for inorganic reflective layer)
As the inorganic reflective layer material applied on the substrate, the following inorganic particles were added at a ratio of 100 g with respect to 100 g of the inorganic binder liquid having the following composition and stirred.
<Inorganic binder liquid (P-Al)>
In Table 1, it is described as an inorganic binder, P—Al.
Phosphoric acid 85% (Wako Pure Chemical) 48g
Aluminum hydroxide (Wako Pure Chemical) 11g
Water 41g
Total 100g

<Inorganic binder solution (Cl-Al)>
In Table 1, it is described as an inorganic binder, Cl—Al.
Hydrochloric acid 35% (Wako Pure Chemical Industries) 31.7g
7.4g of aluminum hydroxide
60.9g of water
Total 100g
<Inorganic binder solution (sodium silicate)>
In Table 1, it describes as an inorganic binder and sodium silicate.
Sodium silicate (No. 3 sodium silicate: Fuji Chemical Co., Ltd.) 80g
20g of water
Total 100g

The inorganic particles shown below were added to the inorganic binder solution to prepare an inorganic reflective layer coating solution.
1) Alumina The alumina particles used are described below. Table 1 shows the refractive index, average particle diameter, type, and composition.
1-1) AL-160SG-3 average particle size 0.52 μm, purity 99.9%, manufactured by Showa Denko KK was used.
1-2) A42-2 average particle diameter 4.7 μm, Purity 99.57%, manufactured by Showa Denko KK was used.
1-3) As a mixture of two kinds of aluminas having different average particle diameters, a mixture of average particle diameters shown in Table 1 as CAI Kasei Nanotek alumina was used. The mixing ratio was set such that particles having an average particle diameter of 0.01 μm were 20% by mass in the total mass of the particles. In Table 1, it is indicated by alumina (different particle size) * 0.
2) Titanium oxide: Fuji Titanium Industry Co., Ltd. TA-100 was used. The refractive index and average particle diameter are shown in Table 1. In Table 1, it is indicated by titanium oxide * 1.
3) Barium sulfate * 2: Toshin Kasei Co., Ltd. B-30 was used. Shown in Table 1 as barium sulfate * 2.
Barium sulfate * 3: Takehara Chemical Industry Co., Ltd. W-1 was used. Shown in Table 1 as barium sulfate * 3.

<4. Modification of inorganic reflective layer>
Among the obtained substrates with an inorganic reflective layer, PDMS (polydimethylsiloxane) was applied to Examples 5 and 17 under the following conditions to modify the inorganic reflective layer.
Solvent: 10g of toluene
Polydimethylsiloxane (trade name: Q7-9120 SILICONE FLUID 20CST, manufactured by DOW CORNINGR) 10g

<5. Formation of metal wiring layer>
A diluted solution of silver nanoparticle ink (XA-436, manufactured by Fujikura Chemical Co., Ltd.) is ejected onto the surface of the obtained reflective substrate in a pattern of a metal wiring layer using an ink jet apparatus (DMP-2831, manufactured by Fuji Film Co., Ltd.). Thus, an Ag wiring (wiring width: 100 μm) was formed. Next, plating was performed with a plating solution containing nickel to form an Ag—Ni wiring.
Finally, plating was performed with a plating solution containing gold to form an Ag—Ni—gold wiring. The thickness of each layer was Ag (20 μm), Ni (4 μm), Au (0.4 μm).

<6. Mounting of light emitting element and formation of wiring>
Next, a commercially available light-emitting element manufactured by GeneLite Co., Ltd., product number OBL-CH1818 was mounted on the surface of the reflective substrate of Examples and Comparative Examples, and was electrically connected to the metal wiring layer by wire bonding or flip chip mounting.
In Examples 13 and 15 and Comparative Example 1, the light-emitting elements were flip-chip mounted through conductive bumps using the through holes as conductive paths.

<7. Formation of light-emitting element sealing layer>
The phosphor material is Y ₃ Al ₅ O ₁₂ : Ce, and this phosphor material is mixed with the glass material layer shown in the table, and a sealing layer is formed under the conditions shown below. Got the device.
(1) After adding ethanol and water to metal alkoxide tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ ] and stirring, hydrochloric acid was added dropwise as a reaction catalyst, and the mixture was further stirred at room temperature and allowed to stand for 24 hours. A precursor was obtained. A phosphor material (Y ₃ Al ₅ O ₁₂ : Ce) is added to this precursor, and after stirring and dispersing, pipetting is performed on the upper surface of the mounted light emitting device, and then heating is performed at 300 ° C. for 1 hour to form a sealing layer. Created. In the case of flip chip mounting, coating was performed to form a uniform sealing layer on the entire surface.
(2) Water glass Add phosphor material (Y ₃ Al ₅ O ₁₂ : Ce) to No. 3 sodium silicate stock solution, stir and disperse, and then pipet on top of mounted light emitting device, then heat at 300 ° C. for 1 hour Thus, a sealing layer was created. In the case of flip chip mounting, coating was performed to form a uniform sealing layer on the entire surface.
(3) Ceramic precursor polymer 15 g of hydridopolysilazane prepared by the method of US Pat. No. 4,540,803, 2 g of glycidoxypropyltrimethoxysilane, and 4 g of dimethylcyclosiloxane were mixed to form a viscous Created a paste. The sealing layer was formed by pipetting on the surface of the mounted light emitting element in the same manner as the metal alkoxide and then heating at 400 ° C. for 1 hour.

<Evaluation of light emitting device>
(1) Reflectance The total reflectivity (total average of SPIN mode) of 400 to 700 nm was measured using a reflection densitometer (CM2600D, manufactured by Konica Minolta Co., Ltd.) for the prepared substrate before metal wiring formation.
(2) Aging deterioration property The light emission efficiency after 100 hours was measured by continuously emitting light at the maximum allowable current of the light emitting element. As the light-emitting device shown in Table 1, a sufficient amount of phosphor with respect to the light-emitting element was used in the glass material layer, and a light-emitting element manufactured by GeneLite, product number OBL-CH1818 was mounted. Light was emitted at 60 mA. The initial light emission intensity at the maximum allowable current and the light emission intensity after 100 hours were measured, and the light emission intensity after 100 hours passed was evaluated as% of the initial light emission intensity value. The results are shown in Table 2. The emission intensity was measured with a spectroradiometer “USR-45V / D” manufactured by USHIO INC.
(3) Heat-resistant temperature In Table 2, the heat-resistant temperature (melting temperature) of each layer was described.

(4) Workability Table 2 shows the following evaluation results as workability.
(AA evaluation, improved boundary layer depth, high adhesion to glass layer)
As a result of cutting the cross section of the obtained light emitting device and observing it with an electron microscope, the depth of the interface considered to be the boundary between the inorganic reflective layer and the glass material layer is deep. It can be seen that the adhesion is very high.
(A evaluation, can be singulated at the final stage)
At the stage where the resulting light emitting device is made into a final product, there are no defects such as peeling off or falling off of the material between the glass material layer and its lower layer when separated into 30 pieces by dicing and separating. Therefore, it can be considered that industrialization is possible with a sufficient safety factor.
(B Evaluation) When the obtained light emitting device is made into a final product, when it is separated into 30 pieces by dicing and separated, no defects are recognized, and it is considered that there is no problem for small scale implementation.
(C evaluation, damage during processing due to insufficient adhesion between alumina and glass layer)
When the final product was cut into 30 pieces by dicing and separated, the white alumina on the substrate and the glass material layer were damaged during processing.
(D Evaluation) There was a light emitting device in which the glass material layer and the lower layer were peeled off when the final product was diced into 30 pieces by dicing. In addition, there was a light-emitting device in which defects such as part of the material falling off were found although they were not peeled off.

(5) Mountability of light-emitting element The following evaluation was performed when mounting a light-emitting element having a product number of OBL-CH1818 manufactured by GeneLite.
A: The process of making a through hole was easy and there was no problem. There was no problem because it was easy to drill the screw holes when mounting with screws.
B: The process of making a through hole was easy and there was no problem. It was difficult to cut the screws when mounting with screws.
C: Through-hole processing (processing to open a through-hole) was difficult.

(Consideration of Examples and Comparative Examples)
The light emitting device of the example has high reflectance and high heat resistance temperature. The adhesion between the inorganic reflective layer and the metal substrate is high, and the processability is excellent.
Examples 5 and 17 in which the inorganic reflective layer is modified are particularly excellent in adhesion between the inorganic reflective layer and the glass material layer.
It was found that in Examples 13 and 15, which were flip-chip mounting after the through-holes were processed by anodizing, singulation could be carried out with a safety factor in the final stage.
In Comparative Example 1, it is difficult to process a ceramic substrate that is a white alumina sintered body, and since the ceramic substrate is in direct contact with the glass material layer, the adhesion between the alumina surface and the glass material layer is insufficient. Damaged during processing. The reflectance of white alumina is also low.
In Comparative Example 2, since there was no anodized layer, the adhesion between the inorganic reflective layer and the metal plate was insufficient, and the processability was poor.
Comparative Example 3 had a white filler-containing resin layer instead of the inorganic reflective layer, had no anodized layer, and had good adhesion, but was deteriorated with time.

DESCRIPTION OF SYMBOLS 1,110 Metal base material 2 Anodized film layer 3 Inorganic reflecting layer 4 Inorganic particle 5 Inorganic binder 6 Phosphor 7 Glass material layer 10 Light emitting element 11 Aluminum plate 15 Electrode plate 17 Conductive bump 19 Bonding wire 20, 21 Through-hole 25 Micropore 30 Light emitting device 130 White resist layer 170 Sealing resin 30, 32, 300 Light emitting device

Claims (13)

1. Having an anodized film layer on at least a part of the surface of the valve metal substrate, and an inorganic reflective layer having inorganic particles and an inorganic binder on the anodized film layer;
   A metal wiring layer and a light emitting element are provided on the inorganic reflective layer,
   A light emitting device having a glass material layer containing a phosphor that seals the inorganic reflective layer, the metal wiring layer, and the light emitting element.
2. The light emitting device according to claim 1, wherein the glass material layer is obtained by applying and curing a material made of a metal alkoxide, a ceramic precursor polymer, or water glass.
3. 3. The light emitting device according to claim 1, wherein the inorganic binder is at least one selected from the group consisting of sodium silicate, aluminum phosphate and aluminum chloride.
4. 4. The light emitting device according to claim 1, wherein the inorganic particles have a refractive index of 1.5 to 1.8 and an average particle size of 0.1 μm to 5 μm.
5. The light emitting device according to any one of claims 1 to 4, wherein the inorganic reflective layer is obtained by low-temperature firing at a temperature of 100 ° C to 300 ° C.
6. The light emitting device according to any one of claims 1 to 5, wherein the inorganic reflective layer is further subjected to a surface modification treatment.
7. The valve metal substrate is at least one metal plate selected from the group consisting of aluminum, tantalum, niobium, titanium, hafnium, zirconium, zinc, tungsten, bismuth and antimony. The light emitting device according to item.
8. The light emitting device according to any one of claims 1 to 7, wherein the light emitting device has a through-hole penetrating the valve metal substrate and the inorganic reflective layer, and the light emitting element is flip-chip mounted.
9. The light emitting device according to any one of claims 1 to 8, wherein two or more kinds of the inorganic particles are included in the inorganic reflective layer.
10. The light emitting device according to any one of claims 1 to 9, wherein the light emitting element is a light emitting diode (LED), and the light emitting device is a light emitting diode device.
11. Anodizing at least part of the surface of the valve metal substrate;
    An inorganic reflective layer is formed on the obtained anodized film layer,
    A metal wiring layer is provided on the inorganic reflective layer, a light emitting element is mounted, the mounted light emitting element is electrically connected to an external electrode,
    A method for manufacturing a light emitting device, wherein the inorganic reflective layer, the metal wiring layer, and the light emitting element are sealed with a glass material containing a phosphor.
12. The method for manufacturing a light emitting device according to claim 11, wherein the valve metal substrate is machined to form a through hole before the anodizing step, and the light emitting element is flip-chip mounted.
13. 13. The light emitting device according to claim 12, wherein the inorganic reflective layer, the metal wiring layer, and the light emitting element are sealed with a glass material containing the phosphor to manufacture a light emitting device, and then separated into a desired unit of light emitting device. Method.

Images