TWI667814B - Light emitting element, light emitting device and manufacturing method thereof - Google Patents

Abstract

Provided are a light-emitting element and a light-emitting device which have improved heat resistance and can be miniaturized.

The light emitting element 10 includes, for example, a semiconductor light emitting element 12 arranged on one surface of the substrate 11 and a phosphor film 13 arranged on the other surface of the substrate 11. The phosphor film 13 is, for example, a phosphor film material that is coated on the other side of the substrate 11 with a binder material containing a phosphor material and a silicon oxide precursor that becomes silicon oxide by hydrolysis or oxidation, and is passed through at normal temperature. Formed by reaction or heat treatment at a temperature below 500 ° C.

Description

Light emitting element, light emitting device and manufacturing method thereof

The present invention relates to a light-emitting element using a phosphor material, a light-emitting device, and a method for manufacturing the same.

As for a light-emitting device using a phosphor, for example, there is known a type in which the phosphor is dispersed and disposed in an epoxy resin or a silicone resin (for example, refer to Patent Document 1 or Patent Document 2). However, this light-emitting device has a problem that it is difficult to achieve high output due to deterioration, deformation, and peeling of the epoxy resin or silicone resin due to the increase in output of the LED or heat generated by the LED. As a countermeasure, for example, a light-emitting device in which a phosphor is dispersed in glass instead of an epoxy resin or a silicone resin has been developed (for example, refer to Patent Documents 3 to 5). According to this light emitting device, the heat resistance of the structure can be improved by using an inorganic material as the dispersant.

Advance technical literature Patent literature

Patent Document 1 Japanese Patent No. 3364229

Patent Document 2 Japanese Patent No. 3824917

Patent Document 3 Japanese Patent Laid-Open No. 2009-91546

Patent Document 4 Japanese Patent Laid-Open No. 2008-143978

Patent Document 5 Japanese Patent Laid-Open No. 2008-115223

However, it is difficult to soften a general low-melting glass to such an extent that it can disperse the phosphor unless it is heated at substantially 500 ° C. or higher (see Example of Reference 4). For example, although heavy metals such as lead can be lowered in melting point, from the perspective of the environment or the impact on the human body, there are very few approved uses of these elements. Therefore, there is a problem that the performance may be deteriorated by the influence of heat depending on the phosphor.

In addition, in the case where the phosphor is dispersed in glass, in order to maintain the strength of the glass as a base material, it is not possible to increase the filling rate of the phosphor. With the increase in the brightness of the LED, there is a problem that the excitation light is transmitted more than necessary. . To suppress this transmission, it is necessary to increase the thickness of the glass for phosphor dispersion. As a result, it is not possible to reduce the thickness of the light-emitting device, and the light transmittance is reduced due to an increase in the thickness of the glass. Furthermore, there is a problem that heat dissipation is hindered.

The present invention has been made based on such problems, and an object thereof is to provide a light-emitting element and a light-emitting device which can improve heat resistance and be miniaturized.

The light-emitting element of the present invention includes a semiconductor light-emitting element disposed on one surface of the substrate, and a phosphor film and a phosphor film disposed on the other surface of the substrate and containing a particulate phosphor material and an adhesive. It is formed by coating a phosphor film raw material on the other surface of the substrate, and reacting it at normal temperature or performing heat treatment at a temperature below 500 ° C. The phosphor film raw material includes: the aforementioned phosphor material; Or oxidation At least one kind of adhesive raw material among a group consisting of a silicon oxide precursor, a silicate compound, silica, and amorphous silicon that becomes silicon oxide.

The light-emitting device of the present invention includes the light-emitting element of the present invention.

The method for manufacturing a light-emitting element and the method for manufacturing a light-emitting device according to the present invention include a step of forming a phosphor film, forming a phosphor material containing particles and In the phosphor film of the adhesive, in the phosphor film forming step, the phosphor film material is coated on the other surface of the substrate, and the phosphor film is formed by reacting it at normal temperature or by heat treatment at a temperature below 500 ° C. The phosphor film raw material includes: a particulate phosphor material; and at least one of a group consisting of a silicon oxide precursor, a silicate compound, silica, and amorphous silicon that is converted to silicon oxide by hydrolysis or oxidation. 1 kind of adhesive material.

A method of manufacturing another light-emitting element and a method of manufacturing a light-emitting device according to the present invention include: a semiconductor light-emitting element forming step of forming a semiconductor light-emitting element on one surface of a substrate; and forming a phosphor containing particles on the other surface of the substrate The phosphor film forming step of the phosphor film of the material and the adhesive. In the phosphor film forming step, the phosphor film raw material is coated on the other side of the substrate, and reacted at room temperature or at a temperature below 500 ° C. The phosphor film is formed by heat treatment, and the raw material of the phosphor film includes: a granular phosphor material; and a silicon oxide precursor, a silicate compound, silica, and a non-silicon oxide containing silicon oxide by hydrolysis or oxidation. A binder raw material for at least one of the groups composed of crystalline silicon.

According to the present invention, since the phosphor film uses a binder mainly composed of an inorganic material, the heat resistance to heat generated from a semiconductor light emitting element can be improved, and high output and high brightness can be achieved. In addition, the phosphor film is coated with at least one selected from the group consisting of a phosphor material and a silicon oxide precursor, a silicate compound, silica, and amorphous silicon that are converted to silicon oxide by hydrolysis or oxidation. It is formed by the raw material of the phosphor film of the adhesive material, so the filling rate of the phosphor material in the phosphor film can be increased, and the thickness of the phosphor film can be reduced. Furthermore, since a semiconductor light-emitting element is formed on one surface of the substrate and a phosphor film is formed on the other surface of the substrate, the light-emitting element and the light-emitting device can be miniaturized, and heat generated from the phosphor material can be passed through the semiconductor. Diffusion of light emitting elements can improve heat dissipation. In addition, since the phosphor film is obtained by reaction at normal temperature or by heat treatment at a temperature below 500 ° C, it can be formed at a low temperature, and the deterioration of the characteristics of the phosphor material can be suppressed.

In addition, if the average particle diameter of the primary particles of the phosphor material is set to 1 μm or more and 20 μm or less, or the surface roughness of the phosphor film is set to 10 μm or less according to the arithmetic mean roughness Ra meter, or When the film thickness distribution is set to within ± 10%, it is possible to suppress stain, uniformize, and stabilize performance.

Furthermore, if a phosphor film is formed on the other surface of the substrate, and then the substrate is cut to form a wafer, the light-emitting element and the light-emitting device of the present invention can be easily manufactured, and the manufacturing efficiency can be improved.

10‧‧‧Light-emitting element

11‧‧‧ substrate

12‧‧‧Semiconductor light emitting element

12A, 12B‧‧‧electrode

13‧‧‧ phosphor film

20‧‧‧light-emitting device

21‧‧‧wiring board

21A, 21B‧‧‧Wiring

22A, 22B‧‧‧

23‧‧‧ reflector frame

FIG. 1 is a diagram showing a configuration of a light emitting element according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a manufacturing process of a light emitting device according to an embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a light-emitting device using the light-emitting element shown in FIG. 1.

FIG. 4 is a characteristic diagram showing a change with time of brightness in an exposure test under a high temperature and high humidity environment of 85 ° C. and 85% RH.

FIG. 5 is a characteristic diagram showing a change with time of brightness in an exposure test under a dry and high-temperature environment at 150 ° C.

FIG. 6 is a characteristic diagram showing a change with time of brightness in an exposure test under a dry and high-temperature environment at 200 ° C.

FIG. 7 is a characteristic diagram showing the relationship between the exposure temperature and the luminous brightness after 24 hours in an exposure test in a dry high-temperature environment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a configuration of a light emitting element 10 according to an embodiment of the present invention. This light emitting element 10 includes, for example, a semiconductor light emitting element 12 disposed on one surface of the substrate 11 and a phosphor film 13 disposed on the other surface of the substrate 11. In addition, the size of each component is shown conceptually in the figure, and does not show an actual dimensional ratio.

The substrate 11 is formed of, for example, a semiconductor light emitting element 12 Sapphire wafers, GaN wafers, and Si wafers are preferred. For example, the higher the light transmittance in the band of 400nm to 800nm, the better. When the substrate 11 is made of sapphire, for example, the surface of the other surface on which the semiconductor light-emitting element 12 is formed may be roughened into a frosted glass shape, a satin shape, or a relief shape to scatter light. The thickness of the substrate 11 is generally, for example, a sapphire wafer of 0.2 mm to 1.0 mm.

In addition, the substrate 11 can be used to form a semiconductor light emitting element. The formation substrate used in the case of 12 may be different from the formation substrate. For example, after the semiconductor light-emitting element 12 is formed on the formation substrate, the formation substrate is separated or removed, or the thickness of the formation substrate is made thin, and the semiconductor light-emitting element 12 is disposed on a substrate 11 different from the formation substrate.

The semiconductor light emitting element 12 has, for example, a structure in which a plurality of semiconductor layers including a light emitting layer are laminated, and a pair of electrodes 12A and 12B are arranged. The semiconductor light emitting element 12 is, for example, an LED, and it is preferable that the semiconductor light emitting element 12 emits ultraviolet light, blue light, or green light in terms of excitation light. Among them, the semiconductor light emitting element 12 is preferably one that emits blue light. The reason is that it is easy to obtain white, and it has the effect of deteriorating the surrounding materials with respect to ultraviolet light, and blue light has less influence on that. This semiconductor light emitting element 12 is preferably a light emitting surface on the side constituting the substrate 11, for example.

The phosphor film 13 is directly disposed on the other surface of the substrate 11, for example. The phosphor film 13, for example, contains a particulate phosphor material and an adhesive to adhere to the phosphor material, and may optionally contain a filler. The phosphor film 13 is coated on the other surface of the substrate 11 with a phosphor-containing material. The raw material of the phosphor film and the raw material of the adhesive are formed by reacting them at room temperature or by heat treatment at a temperature below 500 ° C. As a method of coating, for example, a printing method, a spray method, a drawing method by a dispenser, or a spray method may be mentioned. Among them, a printing method or a spray method is preferable, and a printing method is more preferable.

Phosphor materials, such as those containing phosphor particles, can also be used in A coating layer is formed on the surface of the phosphor particles. The phosphor particles can be selected according to the type of the semiconductor light-emitting element 12 and the like, for example, if the fluorescent light is emitted by the excitation light emitted from the semiconductor light-emitting element 12. As the phosphor material, one kind or two or more kinds of phosphor particles can be used. When plural kinds are used, they can also be mixed and used, and they can also be divided into multiple layers and laminated.

Examples of the phosphor particles include blue phosphors such as BaMgAl ₁₀ O ₁₇ : Eu, ZnS: Ag, Cl, BaAl ₂ S ₄ : Eu, or CaMgSi ₂ O ₆ : Eu; Zn ₂ SiO ₄ : Mn, (Y, Gd) BO ₃ : Tb, ZnS: Cu, Al, (M1) ₂ SiO ₄ : Eu, (M1) (M2) ₂ S: Eu, (M3) ₃ Al ₅ O ₁₂ : Ce, SiAlON : Eu, CaSiAlON: Eu, (M1) Si ₂ O ₂ N: Eu or (Ba, Sr, Mg) ₂ SiO ₄ : Yellow or green phosphors such as Eu, Mn; (M1) ₃ SiO ₅ : Eu Or (M1) S: yellow, orange or red phosphors such as Eu; (Y, Gd) BO ₃ : Eu, Y ₂ O ₂ S: Eu, (M1) ₂ Si ₅ N ₈ : Eu, (M1 ) AlSiN ₃ : Eu or YPVO ₄ : Red-based phosphors such as Eu. In addition, in the above chemical formula, M1 contains at least one of the group consisting of Ba, Ca, Sr, and Mg, M2 contains at least one of Ga and Al, and M3 contains at least one of the group consisting of Y, Gd, Lu, and Te. One.

Wherein, when considering the heat resistance of the phosphor film 13, the phosphor particles to line _{(M3) 3 Al 5 O 12} : Ce, SiAlON: Eu, CaSiAlON: Eu, (M1) Si 2 O 2 N: Eu, (M1) ₂ Si ₅ N ₈ : Eu or (M1) AlSiN ₃ : Eu is preferred. M1 and M3 are as described above.

The coating layer of the phosphor particles includes, for example, a composite oxide containing yttrium and aluminum, such as rare earth oxides, zirconia, titanium oxide, zinc oxide, aluminum oxide, yttrium / aluminum, and garnet, and magnesium oxide. And at least one metal oxide in the group consisting of aluminum and magnesium composite oxides such as MgAl ₂ O ₄ and the like. The reason is to improve the characteristics of water resistance and ultraviolet light resistance. Among them, rare earth oxides or zirconia are preferred. Regarding rare earth oxides, those containing at least one element from the group consisting of yttrium, scandium, cerium, and lanthanum are more preferred, and zirconia is more preferred. The reason is that a higher effect can be obtained and costs can be suppressed.

The average particle size of the primary particles of the phosphor material, such as It is preferably 1 μm or more and 20 μm or less. The reason is that the smaller the average particle diameter is, the more the stains can be suppressed and the uniformity can be achieved. However, if it is too small, there are many cases where the optical properties of the phosphor material itself are reduced, and there are many cases where small particles smaller than 1 μm may agglomerate twice and lose the effect of miniaturization, so it is preferably 1 μm or more.

Adhesives are made by hydrolyzing or oxidizing At least one of the binder raw materials of the group consisting of silicon oxide precursors, silicate compounds, silica, and amorphous silicon is reacted at room temperature or obtained by heat treatment at a temperature below 500 ° C. In terms of the silicon oxide precursor, for example, those containing perhydropolysilazane, ethyl silicate, and methyl silicate as main components are preferred. The reason is that before these silicas The flooding material is easily converted to silicon dioxide, such as silicon dioxide, by hydrolysis or oxidation during normal temperature or heat treatment, and can function as an adhesive. In addition, in terms of adhesives, it is not necessary for the silica precursor to react completely to become silica, and it may also contain unreacted portions or incompletely reacted portions.

In terms of silicate compounds, for example, preferable examples include Sodium silicate. The silicate compound may be used in a dehydrated state or a hydrate. In the case of silica or amorphous silicon, for example, nanometer-sized ultrafine particle powder is preferably used. For example, ultrafine particle powder having an average primary particle diameter of 5 nm to 100 nm is used, and ultrafine particles of 5 nm to 50 nm are used. Powder is better. These silicate compounds, silica or amorphous silicon are dissolved or dispersed in a solvent, heat-treated, dried and solidified, and can function as an adhesive.

Adhesive material heat treatment temperature to reduce substrate 11. The influence of the heat of the semiconductor light-emitting element 12 and the phosphor material, so it is better to be below 500 ° C. When it is necessary to make the heat effect smaller, it is better to be below 300 ° C. If it is set to be below 200 ° C, it is good. In addition, if the raw material of the adhesive is allowed to react at normal temperature, it is preferable because there is no influence of heat. In accordance with the heat resistance characteristics of the substrate 11, the semiconductor light emitting element 12, and the phosphor material, it is appropriate to select the type of the adhesive raw material, and adjust the reaction of the adhesive raw material at room temperature, or perform several heat treatments. In addition, in the case where the phosphor material is easily oxidized and deteriorated due to heat, the environment during the heat treatment should preferably be a non-oxidizing environment such as a nitrogen environment.

The filler is, for example, one that adjusts the filling rate of the phosphor material to The light-transmitting inorganic material is preferred, and examples thereof include silica particles, alumina particles, and zirconia particles. More preferably, silicon oxide particles, Its form can be crystalline or glass. The average particle diameter of the filler is preferably, for example, about 1 to 20 μm, which is the same as that of the phosphor material.

The thickness of the phosphor film 13 is preferably, for example, 10 μm or more and 1 mm or less, and more preferably 20 μm or more and 500 μm or less. The reason is that when the thickness is too thin, the amount of phosphor material becomes small and it is difficult to adjust the color, while when the thickness is too thick, the excessive scattering of light increases the absorption of light and makes it difficult to take the light out. The surface roughness of the phosphor film 13, that is, the surface roughness of the surface of the phosphor film 13 on the side opposite to the substrate 11 is preferably 10 μm or less in terms of the arithmetic average roughness Ra. Furthermore, the phosphor film The film thickness distribution of 13 is preferably within ± 10%. The reason is that the stain can be suppressed, uniformized, and performance stabilized. The surface roughness of the phosphor film 13 or the film thickness distribution of the phosphor film 13 can also be adjusted by, for example, grinding or grinding the surface after the phosphor film 13 is formed.

This light-emitting element 10 can be manufactured, for example, as follows. FIG. 2 is a flowchart showing an example of a process of the light emitting device 10. First, for example, a substrate 11 having a size capable of forming a plurality of light-emitting elements 10 is prepared, and a plurality of semiconductor light-emitting elements are formed on one surface of the substrate 11 (step S101; semiconductor light-emitting element forming step). At that time, the semiconductor light emitting element 12 may also be directly formed on one side of the substrate 11, and after being formed on a formation substrate different from the substrate 11, the formation substrate is separated or removed, or the thickness of the formation substrate is made thin, and the semiconductor The light emitting element 12 may be disposed on one surface of the substrate 11.

Next, for example, a phosphor film 13 is formed on the other surface of the substrate 11 on which the semiconductor light emitting element 12 is formed (step S102; a phosphor film forming step). Specifically, first, on the other side of the substrate 11 A phosphor film material containing a phosphor material and a binder material is applied thereon. For example, if the printing method is used, one or two or more phosphor materials, adhesive materials, diluent solvents, and fillers (if necessary) are mixed to form a paste-like phosphor film material, and then The printing method is, for example, screen printing applied to the other surface of the substrate 11. If applied by screen printing, the uniformity of the film thickness distribution in the surface of the phosphor film 13 can be improved, which is preferable. For example, if the spray method is used, one or two or more phosphor materials, a binder raw material, a diluent solvent, and a filler (if necessary) are mixed to form a slurry-like phosphor film raw material. A spray gun is used to coat the other surface of the substrate 11 together with the spray gas. It is preferable to adjust the spray diameter of the spray to make the spray gun move uniformly while traversing at a certain speed, thereby improving the uniformity of the film thickness distribution in the plane of the phosphor film 13 and is therefore preferred. The application may be repeated until a necessary film thickness is obtained.

In addition, because the spray method OK, so during the spraying, there will be exhaust of the phosphor film raw material, resulting in poor yield. In contrast, screen printing method does not have such a problem, and it can improve the utilization efficiency of the phosphor film raw material, so it is better. Moreover, the screen printing method does not cover the substrate side, and repeats the same patterning by using the mask on the screen side, so that only the necessary parts can be coated, it will not be attached to unnecessary parts, and there is no treatment. Since the fixture is attached, the fixture can be used continuously, which can improve the productivity during mass production, so it is better.

Next, for example, the coated phosphor film material is dried. To remove the dilution vehicle. At that time, if necessary, the temperature may be 500 ° C or lower, more preferably 300 ° C or lower, and heating may be performed in a range of 200 ° C or lower. Thus, the raw material of the adhesive reacts at normal temperature or heat treatment, or Solidification. In addition, the phosphor film 13 may be formed on the entire surface of the substrate 11, or may be formed by patterning a plurality of semiconductor light emitting elements 12 arranged on one surface. Next, the substrate 11 on which the semiconductor light-emitting element 12 and the phosphor film 13 are arranged is cut into wafers, for example, by cutting the semiconductor light-emitting element 12 (step S103; wafer formation step). Thereby, the light emitting element 10 can be obtained.

In addition, in the manufacturing process of the light-emitting element 10 described above, although After the semiconductor light-emitting element 12 is formed on one surface of the substrate 11, the case where the phosphor film 13 is formed on the other surface of the substrate 11 will be described. However, after the phosphor film 13 is formed on the other surface of the substrate 11, A semiconductor light emitting element 12 is formed on one surface of the substrate 11.

FIG. 3 shows a light-emitting device using the fluorescent element 10 One of 20 constitution examples. In this light-emitting device 20, a light-emitting element 10 is mounted on a wiring substrate 21. On the wiring substrate 21, for example, wirings 21A and 21B are arranged. For the light-emitting element 10, for example, the semiconductor light-emitting element 12 is set on the side of the wiring substrate 21, the electrodes 12A, 12B correspond to the wiring 21A, 21B, and the flip chip is mounted on the wiring substrate 21 by the bumps 22A, 22B, and the like . A reflector frame 23 is formed around the light emitting element 10, for example. The sealant may not be provided around the light emitting element 10. The reason is that when the resin is coated with a sealant, the heat dissipation is reduced. Although not shown, a sealant may be disposed on the side of the light emitting element 10 to protect the wiring on the wiring substrate 21. Although not shown, a sealant may be disposed so as to cover the upper surface of the light emitting element 10. The reason is that the influence caused by direct contact with moisture or harmful gas from the outside can be reduced. The light-emitting device 20 can be manufactured using, for example, the light-emitting element 10 manufactured as described above.

Thus, according to this embodiment, since the phosphor film 13 Since an adhesive mainly composed of an inorganic material is used, heat resistance to heat generated from the semiconductor light emitting element 12 can be improved, and high output and high brightness can be achieved. In addition, the phosphor film 13 is coated with at least one selected from the group consisting of a phosphor material and a silicon oxide precursor, a silicate compound, silica, and amorphous silicon that are converted to silicon oxide by hydrolysis or oxidation. It is formed from the raw material of the phosphor film of the adhesive material, so the filling rate of the phosphor material in the phosphor film 13 can be increased, and the thickness of the phosphor film 13 can be reduced. Furthermore, since the semiconductor light-emitting element 12 is formed on one surface of the substrate 11 and the phosphor film 13 is formed on the other surface of the substrate 11, the light-emitting element 10 and the light-emitting device 20 can be further miniaturized, and The heat generated by the bulk material is diffused through the semiconductor light emitting element 12, which can improve heat dissipation. In addition, since the phosphor film 13 can be obtained by reaction at normal temperature or heat treatment at a temperature of 500 ° C. or less, it can be formed at a low temperature, and the deterioration of the characteristics of the phosphor material can be suppressed.

Furthermore, if the average particle diameter of the primary particles of the phosphor material is It can be suppressed if it is 1 μm or more and 20 μm or less, or the surface roughness of the phosphor film 13 is set to 10 μm or less according to the arithmetic mean roughness Ra meter, or the film thickness distribution of the phosphor film 13 is within ± 10%. Color spots, can be uniformized and stabilize performance.

In addition, if a phosphor is formed on the other surface of the substrate 11 After the film 13 is cut and the substrate 11 is cut into wafers, the light-emitting element 10 and the light-emitting device 20 of this embodiment can be easily manufactured, and the manufacturing efficiency can be improved.

Examples (Examples 1-1 to 1-4)

First, a substrate 11 having a semiconductor light emitting element 12 formed on one surface is prepared. As the semiconductor light emitting element 12, a blue LED made of a nitride-based semiconductor is used, and as the substrate 11, a sapphire substrate having a thickness of 0.6 mm is used.

Next, a phosphor material, a binder material, a filler, and a diluent are mixed to produce a phosphor film material. For the phosphor material, phosphor particles composed of Y ₃ Al ₅ O ₁₂ : Ce and phosphor particles composed of CaAlSiN ₃ : Eu, each having an average particle diameter of about 15 μm, were used. In terms of binder raw materials, ethyl silicate was used in Example 1-1, perhydropolysilazane was used in Example 1-2, sodium silicate hydrate was used in Example 1-3, or Example 1 -4 Suspended ultrafine particles of silica or amorphous silicon by solvent. For the filler, silica particles having an average particle diameter of about 15 μm are used. For dilution of the solvent, terpineol was used.

Next, the manufactured phosphor film material is printed on the other surface of the substrate 11 and applied to a necessary thickness. After that, it was dried at 150 ° C to remove the dilution solvent. As a result, a white light-emitting light-emitting element 10 having a phosphor film 13 having a thickness of about 80 μm formed on the other surface of the substrate 11 was obtained according to each embodiment. After the surface roughness of the manufactured phosphor film 13 was measured, the arithmetic average roughness Ra was 10 μm or less. The thickness distribution of the phosphor film 13 was measured to be within ± 10%. In addition, when the light-emitting element 10 of each of the manufactured examples was energized and a light-emitting test was performed, good white light emission was obtained.

(Examples 2-1 to 2-33, Comparative Examples 2-1 to 2-4)

First, a phosphor material and a binder material are mixed, and a solvent and a filler are mixed and diluted to produce a phosphor film material as appropriate. Tables 1 to 4 show the material of the phosphor particles / average particle diameter (particle diameter) / addition amount of the phosphor particles, the material of the filler / average particle diameter ( Particle size) / addition amount, material of the adhesive raw material / addition amount. In addition, as for the phosphor material, both of the phosphor material A and the phosphor material B, or any of them are used. For the dilution solvent, alpha-terpineol was used.

Next, the manufactured phosphor film material is coated on the other surface of the substrate 11 made of a 100 mm square sapphire plate, and then processed by heat treatment or room temperature to form a phosphor film 13 of a predetermined thickness, and then on one surface of the substrate 11 A semiconductor light emitting element 12 is formed thereon, and a light emitting element 10 is obtained. Tables 2 and 4 show the coating method, the heat treatment temperature, the average film thickness of the phosphor film 13, the film thickness distribution of the phosphor film 13, and the phosphor film in each example and each comparative example. The arithmetic mean roughness Ra of 13. Tables 2 and 4 describe the printing by the coating method, specifically, screen printing.

The measurement of the film thickness of the phosphor film 13 is performed by measuring the thickness of the substrate 11 in advance, measuring the thickness after the phosphor film 13 has been formed, and setting the difference as the film thickness. The average film thickness was measured for a total of 25 points in 5 columns and 5 rows of the substrate 11 with a square of 100 mm square. The average value of the film thickness was defined as the average film thickness. The film thickness distribution of the phosphor film 13 is calculated by the following calculation formula. In addition, the maximum film thickness is the maximum value among the film thicknesses measured at 25 points, and the minimum film thickness is the minimum value among the film thicknesses measured at 25 points.

Film thickness distribution (%) = ((maximum film thickness-minimum film thickness) / (maximum film thickness + minimum film thickness)) × 100

The arithmetic average roughness Ra of the phosphor film 13 is measured by a stylus-type surface roughness measuring device.

As shown in Tables 1 and 2, according to Examples 2-1 to 2-33 in which the average particle diameter of the phosphor particles and the filler is 20 μm or less, the film thickness distribution of the phosphor film 13 is made within ± 10%. The arithmetic mean roughness Ra is 10 μm or less.

Regarding the phosphor film 13 manufactured in each example and each comparative example, the initial emission brightness of the initial characteristics was investigated. In the high-temperature and high-humidity test, an exposure test was performed in a high-temperature and high-humidity environment at 85 ° C and 85% RH, and the reduction rate of the luminous brightness after 2000 hours was investigated. Furthermore, in the dry high temperature test, an exposure test was performed in a dry high temperature environment at 150 ° C or 200 ° C, and the reduction rate of the luminous brightness after 2000 hours was investigated. The obtained results are shown in Tables 5 and 6. In Tables 5 and 6, the light emission luminance of the initial characteristics is the relative light emission luminance when the light emission luminance of Example 2-27 is set to 100. The reduction rate of the luminous brightness in the high-temperature and high-humidity test and the drying high-temperature test is the reduction rate of the luminous brightness derived from the initial characteristics in each Example and each Comparative Example.

The results of Example 2-1 and Comparative Example 2-1 among the obtained results are shown in FIGS. 4 to 6. Figure 4 shows the results of the exposure test in a high-temperature and high-humidity environment at 85 ° C and 85% RH. Figure 5 shows the results of the exposure test in a dry and high-temperature environment at 150 ° C. Figure 6 shows the results at 200 ° C. Results of exposure tests in dry, high-temperature environments. The relative brightness values in the case where the initial brightness of each of the vertical axis systems in FIG. 4 to FIG. 6 is set to 100.

Furthermore, Examples 2-1 to 2-4 were heated in an atmospheric oven. And the phosphor film 13 of Comparative Example 2-1 was subjected to a dry high-temperature environment exposure test at 100 ° C to 500 ° C, and the change with time in brightness was investigated. In addition, since the phosphor film 13 may be broken or the like in a high-temperature region exceeding 200 ° C., the appearance is also checked visually at the same time. The exposure time at each temperature was set to 24 hours. Among the obtained results, the results of Example 2-1 and Comparative Example 2-1 are shown in FIG. 7. The vertical axis in FIG. 7 is a relative brightness value when each initial brightness is set to 100. In addition, although not shown in the drawings, the same results as in Example 2-1 were obtained in Examples 2-2 to 2-4.

As shown in Tables 5 and 6, according to this embodiment, the relative luminous brightness of the initial characteristics is 80% or more, but in Comparative Examples 2-2 to 2-4 that have been heat-treated at 550 ° C or higher, it is as low as 70% or less.

In addition, as shown in Tables 5, 6 and FIGS. 4 to 6, in Comparative Example 2-1 using a silicone resin, the reduction rate of luminous brightness in the high-temperature and high-humidity test was 15%. The reduction rate of luminous brightness was 12%. In a dry high-temperature test at 200 ° C, the phosphor film was peeled off after 1200 hours, and the reduction rate of luminous brightness after 1000 hours was 33%. In contrast, according to this embodiment, in any one of the high-temperature and high-humidity test, the high-temperature drying test at 150 ° C, and the high-temperature drying test at 200 ° C, the reduction rate of the luminous brightness was significantly improved to 7% or less.

In addition, as shown in FIG. 7, in Comparative Example 2-1 in which a silicone resin was used, the brightness maintenance ratio decreased as the temperature became higher, and the phosphor film was subjected to chemical changes due to heat at temperatures above 300 ° C. Into smash and peel. In contrast, in Examples 3-1 to 3-4, there was no change in appearance and no decrease in brightness maintenance rate was seen.

In addition, as shown in Tables 1, 2, and 5, compared with the average particle diameter of the phosphor particles greater than 20 μm, the film thickness distribution of the phosphor film 13 is greater than ± 10%, and the arithmetic average roughness Ra is greater than 10 μm. In Examples 2-34 to 2-36, if the average particle diameter of the phosphor particles and the filler is set as Examples 2-1 to 2-33 in which the thickness of the phosphor film 13 is 20 μm or less, the film thickness distribution of the phosphor film 13 is within ± 10%, and the arithmetic mean roughness Ra is 10 μm or less, the relative emission luminance of the initial characteristics is improved.

(Examples 3-1, 3-2)

First, a phosphor material, a binder material, a filler, and a diluent are mixed to produce a phosphor film material. Tables 7 and 8 show the material of the phosphor particles of the phosphor material in each example / the average particle diameter (particle diameter) of the phosphor particles / added amount, the material of the filler / average particle diameter (particle diameter) / Adding amount, material / adding amount of adhesive raw material. For the dilution solvent, alpha-terpineol was used. Next, on the other surface of the substrate 11 composed of a 100 mm square sapphire plate, a phosphor film material manufactured by spraying or brush coating is formed, and then a phosphor film 13 having a predetermined thickness is formed by heat treatment or processing at room temperature. Table 8 shows the coating method, the heat treatment temperature, the average film thickness of the phosphor film 13, the film thickness distribution of the phosphor film 13, and the arithmetic average roughness of the phosphor film 13 in each example. Degrees Ra. Table 8 describes the printing by the coating method, specifically, screen printing. Tables 7 and 8 also show the values of Example 2-1.

As shown in Tables 7 and 8, compared with the application by printing method, In Example 2-1, in Examples 3-1 and 3-2 that were applied by a spray method or a bristle, the film thickness distribution and arithmetic mean roughness Ra of the phosphor film 13 were large, and the relative luminous brightness of the initial characteristics was reduced. That is, it was found that it is preferable that the phosphor film 13 is applied by a printing method.

The present invention has been described with reference to the embodiments. The present invention It is not limited to the above-mentioned embodiment, and various modifications are possible. For example, although the structures of the light-emitting element 10 and the light-emitting device 20 have been specifically described in the above embodiment, other structures may be constructed.

Moreover, in the above-mentioned embodiment, The case where a phosphor film 13 containing one or more phosphor materials is formed on the other surface will be described, but it is also possible to laminate the other surface of the substrate 11 without mixing the two phosphor materials. Forming a phosphor film containing different phosphor materials.

Moreover, in the above-mentioned embodiment, although the semiconductor The light-emitting element 12 is described using a LED, but may be another semiconductor light-emitting element using a laser light-emitting diode or the like. In particular, according to the present invention, since high output can be achieved, it can be suitably used for applications requiring high output, such as laser projectors, LED headlights, or laser headlights.

[Industrial availability]

It can be used in light-emitting elements and light-emitting devices using semiconductor light-emitting elements such as LEDs or laser light-emitting diodes.

Claims (11)

A light-emitting element, comprising: a semiconductor light-emitting element disposed on one surface of a substrate; and a phosphor film disposed on the other surface of the substrate and containing a particulate phosphor material and an adhesive. The phosphor film is formed by coating a phosphor film material on the other side of the substrate, and reacting it at room temperature or performing heat treatment at a temperature below 500 ° C, and contains the phosphor contained in the phosphor material. Particles and silicon oxide, and the raw material of the phosphor film includes: the aforementioned phosphor material; and a group consisting of a silicon oxide precursor, a silicate compound, silica, and amorphous silicon that become silicon oxide by hydrolysis or oxidation At least one of these is a binder material. The light-emitting element according to claim 1, wherein the average particle diameter of the primary particles of the phosphor material is 1 μm or more and 20 μm or less. The light-emitting element according to claim 1, wherein the surface roughness of the phosphor film is 10 μm or less based on the arithmetic average roughness Ra. For example, the light-emitting element of claim 1, wherein the thickness distribution of the phosphor film is within ± 10%. A light-emitting device comprising the light-emitting element according to any one of claims 1 to 4. A method for manufacturing a light-emitting element, comprising a step of forming a phosphor film, which is formed on one side of a substrate on which a semiconductor light-emitting element is formed on the other side to form a fluorescent light containing a particulate fluorescent material and a binder. For a body film, in the foregoing phosphor film forming step, a phosphor film material is coated on the other surface of the substrate, and reacted at room temperature or heat-treated at a temperature below 500 ° C to form a phosphor film. The body film contains the phosphor particles and silicon oxide contained in the foregoing phosphor material; the raw materials of the phosphor film include: a particulate phosphor material; and a silicon oxide precursor containing silicon oxide by hydrolysis or oxidation At least one kind of adhesive raw material among the group consisting of polymer, silicate compound, silica and amorphous silicon. A method for manufacturing a light-emitting element, comprising: a semiconductor light-emitting element forming step of forming a semiconductor light-emitting element on one surface of a substrate; and forming fluorescent light containing a particulate phosphor material and an adhesive on the other surface of the substrate In the phosphor film forming step of a body film, in the aforementioned phosphor film forming step, a phosphor film raw material is coated on the other side of the substrate, and reacted at room temperature or heat treated at a temperature below 500 ° C to form fluorescence. A body film containing phosphor particles and silicon oxide contained in the aforementioned phosphor material; the raw material of the phosphor film comprises: a particulate phosphor material; and a component formed by hydrolysis or oxidation At least one kind of binder raw material among a group consisting of a silicon oxide precursor, a silicate compound, silica, and amorphous silicon. The method for manufacturing a light-emitting element according to claim 6 or 7, further comprising a wafer-forming step of cutting the substrate to form a wafer after the phosphor film forming step. The method for manufacturing a light-emitting element according to claim 6 or 7, wherein, in the aforementioned phosphor film forming step, the phosphor film raw material is coated on the other surface of the substrate by a printing method or a spray coating method. A method for manufacturing a light emitting device, comprising a phosphor film forming step of forming a phosphor film containing a particulate phosphor material and an adhesive on the other surface of a substrate on which a semiconductor light emitting element is formed on one surface. In the foregoing phosphor film forming step, a phosphor film material is coated on the other surface of the substrate, and reacted at normal temperature or subjected to heat treatment at a temperature below 500 ° C. to form a phosphor film. Containing the phosphor particles and silicon oxide contained in the foregoing phosphor material; the phosphor film raw material includes: a particulate phosphor material; and a silicon oxide precursor containing silicon oxide by hydrolysis or oxidation, A binder material for at least one of the group consisting of silicate compounds, silica, and amorphous silicon. A method for manufacturing a light-emitting device, comprising: a semiconductor light-emitting element forming step of forming a semiconductor light-emitting element on one surface of a substrate; and forming fluorescent light containing a particulate fluorescent material and a binder on the other surface of the substrate In the phosphor film forming step of a body film, in the aforementioned phosphor film forming step, a phosphor film raw material is coated on the other surface of the substrate and reacted at room temperature or heat-treated at a temperature below 500 ° C to form a phosphor. A phosphor film containing phosphor particles and silicon oxide contained in the aforementioned phosphor material; the phosphor film raw material comprises: a particulate phosphor material; and It is a binder raw material for at least one of a group consisting of a silicon oxide precursor, a silicate compound, silica, and amorphous silicon that is a silicon oxide.