JP4407204B2 - Light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device of high luminance, high heat dissipation, and high reliability using a ceramic package. <P>SOLUTION: The light-emitting device 100 which has a ceramic package having a concave portion in which an electrical conductor 105 is arranged, and a light-emitting element 103 connected to the electrical conductor 105 in the concave portion, and in which the concave portion is encapsulated with a molding member 107, is characterized in that the inside wall of the concave portion is provided with a light reflector 102 arranged on a bare ceramic section which has a shape widening toward the opening direction, and bare ceramic sections 106 exposed on the peripheries of the light reflector 102 wherein the molding member 107 covers the light reflector 102 and the bare ceramic sections 106. <P>COPYRIGHT: (C)2004,JPO

Description

  The present invention relates to a semiconductor device used for a light source or an indicator of various sensors such as a display or a line sensor capable of displaying various data, and particularly, a highly reliable semiconductor light emission having high heat dissipation and excellent luminous efficiency. It relates to the device.

  Today, LED chips capable of emitting light with ultra-brightness exceeding 1000 mcd in RGB (red, green, and blue) have been developed. Accordingly, an LED display capable of full-color display can be obtained by emitting mixed colors using LED chips capable of emitting RGB (red, green, and blue). Specifically, it is being used for a full-color large video device, a character display board used indoors and outdoors, and the like. In order to display complex characters such as JIS Level 2 Kanji characters, particularly high-definition displays are required. In addition, for applications such as destination display boards both indoors and outdoors, it is also required that the display is visible from a fairly wide angle.

  As a light emitting device capable of high definition, a high viewing angle, and a small and thin shape, a light emitting device in which an LED chip is arranged in a ceramic package can be considered. FIG. 3 shows a schematic cross-sectional view of a conventional light emitting device using such a ceramic package. The LED chip 301 is placed on a conductor wiring 302 provided on a ceramic substrate and sealed with a mold member 303. Such a ceramic-based package can be relatively easily formed by firing a multi-layered raw material called a green sheet.

  Further, when the LED is made to emit light with high luminance, the amount of heat generated from the LED chip increases, but the reliability of the LED chip can be ensured because the heat dissipation of the ceramic is good. Furthermore, in a ceramic package using ceramic, wiring can be easily formed simultaneously with package formation by printing tungsten paste or the like on a green sheet. Since the ceramic package can easily form the concave opening, it has an advantage that the resin sealing for the purpose of protecting the LED chip mounting portion can be easily performed. By directly mounting the LED bare chip, it is possible to use light emission in all directions of the LED chip as compared with a bullet-type LED lamp, so that a display with a high viewing angle can be manufactured (see, for example, Patent Document 1).

JP-A-5-335627.

  Ceramics transmit a certain amount of light due to the ceramic composition and the compactness of the sintered body. Therefore, as indicated by an arrow in FIG. 3, the light emitted in the side surface direction of the LED chip partially enters the ceramic inner wall 304. Light that has entered the inner wall 304 of the recess of the ceramic package passes through the surface layer while being scattered. Therefore, when the light emitting device is observed from the front, weak ring-like light emission is seen on the outer periphery of the recess. Similarly, it is conceivable that light loss in the ceramic package increases. This causes a decrease in light emission luminance in a light emitting device using a ceramic package. Therefore, as disclosed in Japanese Patent Laid-Open No. 5-335627, in order to reflect light incident on the inner wall of the recess in the direction of the light emission observation surface, a light reflecting portion may be provided with a metal material on the inner wall of the ceramic. . As described above, by providing the light reflecting portion, it is possible to suppress the decrease in the light emission luminance as described above.

  However, in the concave portion of the ceramic package, the light reflecting portion and the organic resin that is the mold member have poor adhesion. Furthermore, the metal used for the light reflecting portion is greatly different in thermal expansion coefficient from the mold member. Therefore, there is a problem that the mold member is peeled off from the light reflecting portion due to thermal stress during the temperature cycle. Furthermore, if the inner wall of the recess is tapered so that the opening direction is widened, the mold member that has received stress in the opening direction is more easily removed from the ceramic package body.

  Accordingly, it is an object of the present invention to solve the above-mentioned problems in a semiconductor device using a ceramic package, and to provide a highly reliable semiconductor device with high heat dissipation and excellent luminous efficiency.

In order to achieve the above object, a light-emitting element storage package constituting a light-emitting device according to the present invention includes an insulating base having a concave portion for mounting and storing a light-emitting element on an upper surface, from the bottom surface of the concave portion to the lower surface of the insulating base. A light emitting element storage package comprising: forming a wiring layer to which the electrodes of the light emitting element are electrically connected; and depositing a metal reflective layer on the inner peripheral surface of the concave portion apart from the bottom surface of the concave portion. The inner peripheral surface of the concave portion includes a vertical surface formed on the bottom surface of the concave portion and an inclined surface extending outwardly from the upper surface of the insulating base toward the upper surface of the insulating base. The layer is applied to the inclined surface and is not applied to the vertical surface . The insulating base is preferably a ceramic. The vertical plane is preferably lower than the thickness of the light emitting element. In addition, the present invention includes the light emitting element storage package, a light emitting element that is received and mounted in the recess, and an electrode is electrically connected to the wiring layer, and a transparent resin that covers the light emitting element. The light-emitting device is characterized by the above.

  The ceramic package further includes a second ceramic base portion that surrounds at least a part of the light emitting element and is provided inside the light reflecting portion, and the mold member further covers the second ceramic base portion. To do. Further, it is preferable that the first ceramic base portion and the second ceramic base portion include at least a pair of substantially parallel surfaces, and the surfaces are covered with the mold member. It is preferable that the ceramic package has a stepped ceramic base portion at the opening of the recess. In addition, the present invention provides a ceramic package having a recess, a light emitting element disposed in the recess, a light reflecting portion provided continuously from the inner wall surface of the recess to the upper surface of the ceramic package, and the interior of the recess. A mold member for sealing, wherein the mold member covers the ceramic base portion exposed to a part of the inner wall surface of the recess and the bottom surface of the recess. The recess preferably includes a plurality of ceramic base portions that are substantially symmetrical to each other with respect to the light-emitting element placed on the bottom surface thereof and that are covered with the mold member.

  If comprised in this way, the stress which arises between a mold member and a ceramic package will be relieved, and it will be relieved, and it can be set as a more reliable light-emitting device, without producing peeling of a mold member and a package. .

The light-emitting element can include an alkaline earth metal silicate activated with europium. With this configuration, a light-emitting device that can emit light having different wavelengths by absorbing a part of light from the light-emitting element by the phosphor can be obtained.

  The invention of the present application can be a light-emitting device having a high viewing angle, high definition, small size, thinness, and high reliability. In particular, by adopting the configuration of claim 1, it is possible to provide a light-emitting device that can efficiently reflect light from the LED chip and achieve both compatibility with a mold member and the like. Therefore, it has effects such as water resistance due to improved adhesion between the coating resin and the ceramic package and stress relaxation during the temperature cycle.

  In the present invention, the metal layer that reflects light from the LED chip is functionally separated into adhesiveness and reflectivity with ceramics and the like. Specifically, adhesion can be improved by using metal particles as the first metal layer. In addition, the second metal layer provided on the inner wall of the recess can improve the light reflection efficiency. That is, by providing the first and second metal layers, the optical loss that has entered the ceramic package can be reduced. Further, since light emission other than in the concave portion is prevented, when the light emitting device according to the present invention is used as a display, it is possible to improve the contrast of the display or the like.

  In addition, the light reflecting portion having a metal material on the surface and the organic resin as the mold member are inherently poor in adhesion, but by providing a ceramic base portion on a part of the inner wall portion of the present invention, the adhesion can be improved. It is possible to improve and relieve thermal stress. Thereby, the sealing hermeticity of the light emitting device is improved, peeling of the mold material due to thermal stress during the temperature cycle is prevented, and improvement in reliability of the light emitting device using the ceramic package can be expected.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, the form shown below illustrates the light emitting device for embodying the technical idea of the present invention, and the present invention does not limit the light emitting device to the following. Further, the size and positional relationship of the members shown in the drawings are exaggerated for clarity of explanation. In particular, it goes without saying that the shape of the exposed ceramic body is not limited to the shape shown in the drawings.

Embodiment 1 FIG.
As a result of various experiments, the inventor of the present application has provided a light reflecting portion on a part of the wall surface in the concave portion of the ceramic package, and the ceramic base portion is exposed from the light reflecting portion around the light reflecting portion. As a result, it has been found that light emission characteristics and reliability can be remarkably improved by suppressing peeling from the ceramic package.

  That is, in a light emitting device using a ceramic material for a package, the concave portion is processed into a tapered shape whose inner diameter is widened in the opening direction, and the concave portion is formed as a light reflecting portion that reflects incident light toward the light emission observation surface. Provided on a part of the inner wall. By doing so, it is possible to suppress ring-shaped light emission that has been transmitted through the ceramic and generated on the light emission observation surface side, and the light reflecting portion reflects light incident on the light emission observation surface side. A light-emitting device capable of emitting light with high luminance can be formed. Further, the ceramic base portion is exposed in the vicinity of the light reflecting portion, for example, in the vicinity of the opening of the concave portion as viewed from the main surface direction of the light emitting device, or the ceramic base portion has a stepped structure. Further, the concave portion of the ceramic package is sealed with a mold member so that the mold member covers at least the light reflecting portion and the exposed ceramic base portion. By adopting such a structure, the stress applied to the mold member due to thermal expansion is canceled by the ceramic base exposed at the periphery of the light reflecting portion, so that the mold member can be prevented from peeling off. It is.

  By the way, when forming a light reflection part integrally with a ceramic, it is preferable to use a refractory metal. However, the refractory metal does not always reflect light from the LED chip efficiently. The present invention can achieve efficient light emission and reliability by functionally separating the adhesiveness and reflectivity with ceramics. Further, by selecting the unevenness on the surface of the inner wall of the opening, it is possible to control the adhesion with the mold member, and the reliability of the mold member is reduced even when the resin is thermally expanded.

Embodiment 2. FIG.
Further, the inventors of the present application together with the first ceramic base exposed to the periphery of the light reflecting portion, the second light emitting device surrounds the light emitting element inside the light reflecting portion when viewed from the main surface direction of the light emitting device. A ceramic base is provided, and the first and second ceramic bases are configured to have at least one pair of substantially parallel surfaces in the recess. Further, the mold member covers at least the light reflecting portion and the first and second ceramic base portions. By providing surfaces substantially parallel to each other on the ceramic base portion, it is possible to relieve stress from various directions on the mold member regardless of the shape of the light reflecting portion such as an inclined light reflecting portion. Therefore, it has been found that such a configuration can suppress the peeling of the mold member from the ceramic package and can dramatically improve the light emission characteristics and the reliability, thereby achieving the present invention. Hereinafter, various constituent requirements of the present invention will be described in detail.

[Ceramic package]
The ceramic package used in the present invention is formed of a ceramic material to protect the LED chip from the external environment or the like. The LED chip is disposed in the recess and the LED chip and the outside are electrically connected. A member to be connected is provided. Specifically, the ceramic material is preferably alumina, aluminum nitride, mullite or the like. In particular, 90 to 96% by weight of the raw material powder is alumina, and 4 to 10% by weight of viscosity, talc, magnesia, calcia, silica and the like are added as sintering aids and sintered in a temperature range of 1500 to 1700 ° C. 40-60% by weight of ceramics and raw material powder is alumina, and 60-40% by weight of borosilicate glass, cordierite, forsterite, mullite, etc. are added as sintering aids and sintered in the temperature range of 800-1200 ° C. And ceramics.

  Such a package can take various shapes at the green sheet stage before firing. The conductor wiring in the package is formed from a paste-like material in which a refractory metal such as tungsten or molybdenum is contained in a resin binder. By a method such as screen printing, a desired shape is obtained through a through hole provided in the paste-like material green sheet, and a conductor wiring is formed by ceramic firing. A recess for mounting the LED chip is formed by, for example, laminating green sheets having through holes in multiple layers. Therefore, it is possible to form a stepped inner wall of a stepped portion by stacking green sheets having different circular, elliptical, or hole diameters when viewed from the light emission observation surface side. Furthermore, by combining a green sheet having a through-hole whose inner diameter increases in a certain direction and a green sheet having a through-hole of various shapes and sizes, a concave portion having a shape whose inner diameter increases toward the opening direction; can do. Here, a green sheet having a through-hole whose inner diameter increases in a certain direction can be formed by cutting using a cutting tool having a blade having a shape that narrows in a contact direction with the green sheet. . Or it is possible to form by changing the contact angle with respect to the green sheet surface of the cutting tool used when forming a normal through-hole. Furthermore, a plurality of green sheets having through-holes whose inner diameters are changed in stages are overlapped to form a staircase inner wall for the time being, and a molding die is pressed against the staircase inner wall. By doing so, it is possible to form a green sheet having a through-hole whose inner diameter increases in a certain direction.

After laminating such green sheets, a ceramic package can be obtained by sintering. _{Further, Cr 2 O 3, MnO 2} , etc. TiO 2, _Fe 2 _{O 3} can also be a dark color by incorporating in the green sheet itself.

  The concave portion of the package is for placing an LED chip, a conductive wire, or the like inside. Therefore, it is sufficient that the LED chip is large enough to be directly mounted on a die-bonding device or the like and to be electrically connected to the LED chip by wire bonding or the like. Two or more recesses can be provided as desired. Specifically, various selections such as a 16 × 16 or 24 × 24 dot matrix or a linear shape can be made. When the dot pitch of the recesses is high and fine with 4 mm or less, the dot pitch can be greatly reduced as compared with the case where a bullet-type LED lamp is mounted. Further, with the configuration of the present invention, various problems related to heat dissipation from the LED chip can be solved even in such a high density. Adhesion between the LED chip and the bottom of the package can be performed with a thermosetting resin or the like. Specifically, an epoxy resin, an acrylic resin, an imide resin, etc. are mentioned. In addition, Ag paste, ITO paste, carbon paste, metal bump, or the like can be used for electrical connection with wiring such as a face-down LED chip. Further, the light emitting element may be directly fixed to the exposed ceramic base portion via an insulating adhesive. By comprising in this way, a light emitting element is firmly fixed with respect to a ceramic package compared with the case where it fixes to a conductor wiring via an insulating adhesive agent.

[Light Reflector 102]
The light reflecting portion 102 is provided on a part of the inner wall surface forming the recess on the main surface side (light emission observation surface side) of the ceramic package, and is in direct contact with the ceramic base portion of the ceramic package. A first metal layer serving as a base and a second metal layer having a reflection function for reflecting light emitted from the LED chip and efficiently extracting the light to the outside are included. Hereinafter, the first metal layer and the second metal layer will be described in detail.

(First metal layer)
The first metal layer is formed in direct contact with the ceramic package and serves as a base on which the second metal layer is formed. Therefore, it is necessary that the first metal layer formed simultaneously with the ceramic firing does not melt when the ceramic is formed. Examples of the refractory metal used for the first metal layer include tungsten, chromium, titanium, cobalt, molybdenum, and alloys thereof. The first metal layer can be formed by mixing these metal particles with a resin paste, coating or printing on the inner wall of the concave portion of the green sheet, and firing together with the green sheet. By controlling the particle size of the metal particles, the adhesion between the ceramic and the second metal layer formed on the first metal layer, and the mold member formed thereon can be controlled. The surface roughness of the second metal layer formed thereon can be controlled by the metal particle size used in the first metal layer. Therefore, the particle size of the metal particles contained in the first metal layer is preferably 0.3 to 100 μm, and more preferably 1 to 20 μm.

  As a method of forming a reflective conductor layer other than screen printing the inner wall surface, the center of the opening is laser-exposed within a range in which the conductor layer is left on the inner wall after the conductor paste is completely poured and embedded in the opening of the green sheet. You may use the method of drilling. In this case, preferred examples of the laser light source include a carbon dioxide laser, a YAG laser, and an excimer laser. Furthermore, the first metal layer is not necessarily formed on the entire inner wall. By partially not forming the first metal layer and the second metal layer, light is reflected only in a desired direction. The part where the metal layer is not formed seems to transmit light through the ceramic. Thus, by partially forming the metal layer to be formed on the inner wall, the viewing angle can be expanded in a desired direction. Moreover, it can also form as a 1st metal layer which comprises a light reflection part by apply | coating the high melting point metal containing resin paste which comprises conductor wiring to an inner wall.

(Second metal layer)
The second metal layer of the present invention is formed on the first metal layer and has a reflection function for efficiently taking out the light emitted from the LED chip to the outside. Such a second metal layer can be formed relatively easily on the first metal layer using plating, vapor deposition, or the like. Specifically, the second metal layer has a reflectance of 90% or more with respect to the light emitted from the LED chip, such as gold, silver, platinum, copper, aluminum, nickel, palladium and alloys thereof, and multilayer films thereof. The metal which has is mentioned suitably.

  The second metal layer can be formed simultaneously with the surface treatment of the conductor wiring pattern wired in the ceramic package. That is, there are cases where Ni / Ag or Ni / Au is plated simultaneously with the formation of the second metal layer in consideration of solder connectivity etc. on the conductor wiring provided in the ceramic package. Alternatively, the formation of the second metal layer and the surface of the conductive wiring may be separately electroplated. By covering the surface of the conductive wiring disposed on the bottom surface of the concave portion with the second metal layer, it is possible to suppress light loss below the LED chip.

[LED chip 103]
The LED chip 103 used in the present invention is one in which a semiconductor such as GaAlN, ZnS, ZnSe, SiC, GaP, GaAlAs, AlN, InN, AlInGaP, InGaN, GaN, and AlInGaN is formed as a light emitting layer on a substrate. . Examples of the semiconductor structure include a homo structure having a MIS junction, a PIN junction, and a PN junction, a hetero structure, and a double hetero structure. Various emission wavelengths can be selected from ultraviolet light to infrared light depending on the material of the semiconductor layer and the degree of mixed crystal. The light emitting layer may have a single quantum well structure or a multiple quantum well structure which is a thin film in which a quantum effect is generated.

  When considering use in the outdoors, it is preferable to use a gallium nitride compound semiconductor as a semiconductor material capable of forming a high-luminance light-emitting element. In red, gallium / aluminum / arsenic semiconductors and aluminum / indium / gallium are used. -Although it is preferable to use a phosphorus-type semiconductor, it cannot be overemphasized that it can utilize variously by a use.

  When a gallium nitride compound semiconductor is used, a material such as sapphire, spinel, SiC, Si, ZnO, or GaN single crystal is used for the semiconductor substrate. A sapphire substrate is preferably used to form gallium nitride with good crystallinity with high productivity. An example of an LED chip using a nitride compound semiconductor is shown. A buffer layer such as GaN or AlN is formed on the sapphire substrate. A first contact layer made of N or P-type GaN, an active layer made of an InGaN thin film having a quantum effect, a clad layer made of P or N-type AlGaN, and a second contact made of P or N-type GaN. It can be set as the structure which formed the contact layer in order. Gallium nitride-based compound semiconductors exhibit N-type conductivity without being doped with impurities. When forming a desired N-type gallium nitride semiconductor such as improving luminous efficiency, Si, Ge, Se, Te, C, etc. are preferably introduced as appropriate as N-type dopants.

  On the other hand, when a P-type gallium nitride semiconductor is formed, a P-type dopant such as Zn, Mg, Be, Ca, Sr, or Ba is doped. Since a gallium nitride based semiconductor is difficult to be converted into a P-type simply by doping with a P-type dopant, it is necessary to make it P-type by annealing it by heating in a furnace, low electron beam irradiation, plasma irradiation or the like after introducing the P-type dopant. The semiconductor wafer thus formed is partially etched to form positive and negative electrodes. Thereafter, the LED chip can be formed by cutting the semiconductor wafer into a desired size.

  A plurality of such LED chips can be used as appropriate, and the color mixing property in white display can be improved by the combination thereof. For example, two LED chips that can emit green light and one LED chip that can emit blue and red light can be used. In order to use as a full color light emitting device for a display device, it is preferable that a red light emission wavelength is 610 nm to 700 nm, a green light emission wavelength is 495 nm to 565 nm, and a blue light emission wavelength is 430 nm to 490 nm. In the light emitting device of the present invention, in the case where white mixed color light is emitted, the emission wavelength of the light emitting element should be 400 nm or more and 530 nm or less in consideration of the complementary color relationship with the emission wavelength from the fluorescent material, deterioration of the translucent resin, and the like. Preferably, it is 420 nm or more and 490 nm or less. In order to further improve the excitation and emission efficiency of the light emitting element and the fluorescent material, 450 nm or more and 475 nm or less are more preferable. Note that a light-emitting element having a main light emission wavelength in an ultraviolet region shorter than 400 nm or a short wavelength region of visible light can be used in combination with a member that is relatively difficult to be deteriorated by ultraviolet rays.

[Mold member 107]
The mold member is disposed in the opening of the ceramic package and protects the LED chip from external force or moisture from the external environment and efficiently emits light from the LED chip to the outside. As a specific material constituting such a mold member, a transparent resin or glass having excellent weather resistance such as an epoxy resin, a urea resin, or silicone is preferably used. When LED chips are arranged at a high density, it is more preferable to use an epoxy resin, a silicone resin, or a combination thereof in consideration of disconnection of the conductive wire due to thermal shock. Further, a diffusing agent may be contained in the mold member in order to further increase the viewing angle. As a specific diffusing agent, barium titanate, titanium oxide, aluminum oxide, silicon oxide or the like is preferably used. Moreover, an organic or inorganic coloring dye or coloring pigment can be contained for the purpose of cutting an undesired wavelength. Furthermore, a fluorescent material that converts the wavelength of at least part of the light from the LED chip can also be included.

[Fluorescent substance]
The fluorescent material used in the present invention absorbs part of visible light and ultraviolet light emitted from the light emitting element, and emits light having a wavelength different from the wavelength of the absorbed light. In addition to being contained in the above-described mold member, the fluorescent material in the present embodiment is in a coating member provided so as to cover the LED chip separately from the mold member, or an insulating property for fixing the LED chip to the package It is contained in an adhesive (for example, a translucent inorganic member such as epoxy resin, silicone resin, glass). In addition to being provided so as to cover the surface of the mold member, the fluorescent substance in the present embodiment is provided in the mold member as a layer containing a phosphor at a position spaced from the surface of the mold member and the light emitting element. You can also.

The phosphor used in the present embodiment is a phosphor that emits light that has been wavelength-converted and excited by light emitted from at least the semiconductor light emitting layer of the LED chip, together with a binder that fixes the phosphor. The wavelength conversion member is used. In this embodiment, a phosphor that is excited by ultraviolet light and generates light of a predetermined color can be used as a phosphor. As a specific example, for example,
(1) Ca ₁₀ (PO ₄ ) ₆ FCl: Sb, Mn
(2) M ₅ (PO ₄ ) ₃ Cl: Eu (where M is at least one selected from Sr, Ca, Ba, Mg)
(3) BaMg ₂ Al ₁₆ O ₂₇ : Eu
(4) BaMg ₂ Al ₁₆ O ₂₇ : Eu, Mn
(5) 3.5MgO.0.5MgF ₂ .GeO ₂ : Mn
(6) Y ₂ O ₂ S: Eu
(7) Mg ₆ As ₂ O ₁₁ : Mn
(8) Sr ₄ Al ₁₄ O ₂₅ : Eu
(9) (Zn, Cd) S: Cu
(10) SrAl ₂ O ₄ : Eu
(11) Ca ₁₀ (PO ₄ ) ₆ ClBr: Mn, Eu
(12) Zn ₂ GeO ₄ : Mn
(13) Gd ₂ O ₂ S: Eu, (14) La ₂ O ₂ S: Eu, and the like.

  In addition, these phosphors may be used alone in a single-layer wavelength conversion member, or may be used as a mixture. Furthermore, they may be used alone or in combination in a wavelength conversion member in which two or more layers are laminated.

  When the light emitted from the LED chip and the light emitted from the phosphor are in a complementary color relationship, white mixed color light can be emitted by mixing each light. Specifically, the light emitted from the LED chip and the phosphor light excited and emitted thereby correspond to the three primary colors of light (red, green, and blue), or the blue light emitted from the LED chip. And yellow light of a phosphor that is excited to emit light.

  The emission color of the light emitting device can be adjusted by variously adjusting the ratio of the phosphor and various members such as glass and inorganic members such as glass, the settling time of the phosphor, the shape of the phosphor, and the LED chip. By selecting the emission wavelength, it is possible to provide an arbitrary white color tone such as a light bulb color. From the light emission observation surface side of the light emitting device, it is preferable that the light from the LED chip and the light from the phosphor are efficiently transmitted through the mold member.

Specific phosphors include cadmium zinc sulfide activated with copper and yttrium / aluminum / garnet phosphor (hereinafter sometimes referred to as “YAG phosphor”) activated with cerium. It is done. In particular, at the time of high luminance and long-term use _{(Re 1-x Sm x)} 3 (Al 1-y Ga y) 5 O 12: Ce (0 ≦ x <1,0 ≦ y ≦ 1, where, Re Is at least one element selected from the group consisting of Y, Gd, and La).

_{(Re 1-x Sm x)} 3 (Al 1-y Ga y) 5 O 12: Ce phosphor, for garnet structure, heat, resistant to light and moisture, the peak of the excitation spectrum can be like in the vicinity of 470nm Can do. In addition, the emission peak is in the vicinity of 530 nm, and a broad emission spectrum that extends to 720 nm can be provided.

Two or more kinds of phosphors may be mixed as the phosphor in the light emitting device in this embodiment. That, Al, Ga, Y, the content of La and Gd and Sm are two or more kinds of _{(Re 1-x Sm x)} 3 (Al 1-y Ga y) 5 O 12: by mixing Ce phosphor RGB wavelength components can be increased. At present, there are variations in the emission wavelength of the semiconductor light emitting device, so that two or more kinds of phosphors can be mixed and adjusted to obtain a desired white mixed color light or the like. Specifically, by adjusting the amount of phosphors having different chromaticity points in accordance with the emission wavelength of the light emitting element, the arbitrary points on the chromaticity diagram connected between the phosphors and the light emitting element are caused to emit light. be able to.

  Such a phosphor can be dispersed in a gas phase or a liquid phase and released uniformly. The phosphor in the gas phase or liquid phase is precipitated by its own weight. In particular, in a liquid phase, a layer having a phosphor with higher uniformity can be formed by allowing the suspension to stand. A desired amount of phosphor can be formed by repeating a plurality of times as desired.

  Two or more kinds of phosphors formed as described above may be present in a single-layer wavelength conversion member on the surface of the light-emitting device, or one or two of each of the two-layer wavelength conversion member. There may be more than one type. In this way, white light can be obtained by mixing colors from different types of phosphors. In this case, it is preferable that the average particle diameters and shapes of the phosphors are similar in order to better mix the light emitted from the phosphors and reduce color unevenness. Here, in the present invention, the particle size of the phosphor is a value obtained by a volume-based particle size distribution curve, and the volume-based particle size distribution curve can be obtained by measuring the particle size distribution of the phosphor by a laser diffraction / scattering method. Is. Specifically, in an environment where the temperature is 25 ° C. and the humidity is 70%, the phosphor is dispersed in a sodium hexametaphosphate aqueous solution having a concentration of 0.05%, and a laser diffraction particle size distribution analyzer (SALD-2000A) It was obtained by measuring in a particle size range of 0.03 μm to 700 μm.

  The phosphor used in the present embodiment is a combination of an aluminum garnet phosphor typified by a YAG phosphor and a phosphor capable of emitting red light, particularly a nitride phosphor. Can also be used. These YAG phosphors and nitride phosphors may be mixed and contained in the wavelength conversion member, or may be separately contained in the wavelength conversion member composed of a plurality of layers. Hereinafter, each phosphor will be described in detail.

(Aluminum / garnet phosphor)
The aluminum garnet phosphor used in the present embodiment includes Al and at least one element selected from Y, Lu, Sc, La, Gd, Tb, Eu, and Sm, and Ga and In. It is a phosphor that contains one selected element and is activated by at least one element selected from rare earth elements, and is a phosphor that emits light when excited by visible light or ultraviolet light emitted from an LED chip. . For example, in addition to the YAG phosphor described above, Tb _2.95 Ce _0.05 Al ₅ O ₁₂ , Y _2.90 Ce _0.05 Tb _0.05 Al ₅ O ₁₂ , Y _2.94 Ce _0.05 Pr _{0.01 Al 5 O 12, Y 2.90} Ce 0.05 Pr 0.05 Al 5 O 12 and the like. Among these, in the present embodiment, two or more yttrium / aluminum oxide phosphors containing Y and activated by Ce or Pr and having different compositions are used.

  Blue light emitted from a light emitting element using a nitride compound semiconductor in the light emitting layer and green light and red light emitted from a phosphor whose body color is yellow to absorb blue light, or When yellow light and green light and red light are mixedly displayed, a desired white light emission color display can be performed. In order to cause this color mixture, the light emitting device can contain phosphor powder and bulk in various resins such as epoxy resin, acrylic resin or silicone resin, and translucent inorganic materials such as silicon oxide and aluminum oxide. Thus, the thing containing the fluorescent substance can be variously used according to uses, such as a dot-like thing and a layer-like thing formed so thinly that the light from the LED chip is transmitted. By adjusting the ratio, coating, and filling amount of the phosphor and the translucent inorganic substance and selecting the emission wavelength of the light emitting element, it is possible to provide an arbitrary color tone such as a light bulb color including white.

  In addition, by arranging two or more kinds of phosphors in order with respect to the incident light from the light emitting element, a light emitting device capable of efficiently emitting light can be obtained. That is, on a light emitting element having a reflective member, a color conversion member containing a phosphor that has an absorption wavelength on the long wavelength side and can emit light at a long wavelength, and an absorption wavelength on the longer wavelength side that has a longer wavelength. The reflected light can be used effectively by laminating a color conversion member capable of emitting light at a wavelength.

When YAG phosphor is used, sufficient light resistance with high efficiency even when it is placed in contact with or close to an LED chip having an irradiance of (Ee) = 0.1 W · cm ^{−2 to} 1000 W · cm ⁻² The light emitting device can be made to have the property.

  The cerium-activated yttrium / aluminum oxide phosphor used in the present embodiment, which is a green-based YAG phosphor capable of emitting light, has a garnet structure and is resistant to heat, light and moisture, and is excited and absorbed. The peak wavelength of the spectrum can be in the vicinity of 420 nm to 470 nm. Also, the emission peak wavelength λp is near 510 nm, and has a broad emission spectrum that extends to the vicinity of 700 nm. On the other hand, the YAG phosphor that emits red light, which is an yttrium-aluminum oxide phosphor activated by cerium, has a garnet structure, is resistant to heat, light and moisture, and has a peak wavelength of 420 nm in the excitation absorption spectrum. To about 470 nm. Further, the emission peak wavelength λp is in the vicinity of 600 nm, and has a broad emission spectrum that extends to the vicinity of 750 nm.

  Of the composition of YAG phosphors with a garnet structure, the emission spectrum is shifted to the short wavelength side by substituting part of Al with Ga, and part of Y of the composition is replaced with Gd and / or La. By doing so, the emission spectrum shifts to the long wavelength side. In this way, it is possible to continuously adjust the emission color by changing the composition. Therefore, an ideal condition for converting white light emission by using blue light emission of the nitride semiconductor is provided such that the intensity on the long wavelength side is continuously changed by the composition ratio of Gd. If the substitution of Y is less than 20%, the green component is large and the red component is small, and if it is 80% or more, the redness component is increased but the luminance is drastically decreased. Similarly, the excitation absorption spectrum is shifted to the short wavelength side by substituting part of Al with Ga in the composition of the YAG phosphor having a garnet structure. By substituting a part of Gd and / or La, the excitation absorption spectrum is shifted to the longer wavelength side. The peak wavelength of the excitation absorption spectrum of the YAG phosphor is preferably on the shorter wavelength side than the peak wavelength of the emission spectrum of the light emitting element. With this configuration, when the current input to the light emitting element is increased, the peak wavelength of the excitation absorption spectrum substantially matches the peak wavelength of the emission spectrum of the light emitting element, so that the excitation efficiency of the phosphor is not reduced. Thus, a light emitting device in which the occurrence of chromaticity deviation is suppressed can be formed.

  Such phosphors use oxides or compounds that easily become oxides at high temperatures as raw materials for Y, Gd, Ce, La, Al, Sm, Pr, Tb and Ga, and they are added in a stoichiometric ratio. Mix thoroughly to obtain the raw material. Or a coprecipitated oxide obtained by calcining a solution obtained by coprecipitation of oxalic acid with a solution obtained by dissolving a rare earth element of Y, Gd, Ce, La, Sm, Pr, and Tb in an acid at a stoichiometric ratio with acid; Aluminum and gallium oxide are mixed to obtain a mixed raw material. An appropriate amount of fluoride such as ammonium fluoride is mixed with this as a flux and packed in a crucible, fired in air at a temperature range of 1350 to 1450 ° C. for 2 to 5 hours to obtain a fired product, and then the fired product in water. It can be obtained by ball milling, washing, separating, drying and finally passing through a sieve. Further, in the method for manufacturing a phosphor according to another embodiment, a first firing step in which a mixture composed of a mixture of phosphor materials and a flux is mixed in the atmosphere or in a weak reducing atmosphere, and in a reducing atmosphere. It is preferable to perform the baking in two stages, which includes the second baking step performed in step (b). Here, the weak reducing atmosphere refers to a weak reducing atmosphere set to include at least the amount of oxygen necessary in the reaction process of forming a desired phosphor from the mixed raw material. By performing the first firing step until the formation of the phosphor structure is completed, blackening of the phosphor can be prevented and a decrease in light absorption efficiency can be prevented. In addition, the reducing atmosphere in the second firing step refers to a reducing atmosphere stronger than the weak reducing atmosphere. By firing in two stages in this way, a phosphor with high absorption efficiency at the excitation wavelength can be obtained. Therefore, when a light emitting device is formed with the phosphor thus formed, the amount of the phosphor necessary for obtaining a desired color tone can be reduced, and a light emitting device with high light extraction efficiency can be formed. Can do.

  Yttrium / aluminum oxide phosphors activated with two or more types of cerium having different compositions may be used in combination, or may be arranged independently. When the phosphors are arranged independently, it is preferable to arrange the phosphors in the order of the phosphor that easily absorbs and emits light from the light emitting element on the shorter wavelength side and the phosphor that easily absorbs and emits light on the longer wavelength side. This makes it possible to efficiently absorb and emit light.

(Nitride phosphor)
The fluorescent material in the present embodiment contains N and at least one element selected from Be, Mg, Ca, Sr, Ba, and Zn, and C, Si, Ge, Sn, Ti, Zr, and Hf And a nitride-based phosphor activated with at least one element selected from rare earth elements. The nitride-based phosphor used in the present embodiment refers to a phosphor that emits light when excited by absorbing visible light, ultraviolet light, and light emitted from the YAG-based phosphor emitted from the LED chip. For example, Ca—Ge—N: Eu, Z system, Sr—Ge—N: Eu, Z system, Sr—Ca—Ge—N: Eu, Z system, Ca—Ge—O—N: Eu, Z system, Sr—Ge—O—N: Eu, Z system, Sr—Ca—Ge—ON: Eu, Z system, Ba—Si—N: Eu, Z system, Sr—Ba—Si—N: Eu, Z Type, Ba-Si-ON: Eu, Z type, Sr-Ba-Si-ON: Eu, Z type, Ca-Si-CN: Eu, Z type, Sr-Si-CN : Eu, Z system, Sr-Ca-Si-CN: Eu, Z system, Ca-Si-C-O-N: Eu, Z system, Sr-Si-C-O-N: Eu, Z system Sr—Ca—Si—C—O—N: Eu, Z series, Mg—Si—N: Eu, Z series, Mg—Ca—Sr—Si—N: Eu, Z series, Sr—Mg—Si— N: Eu, Z-based, Mg-Si-O- : Eu, Z series, Mg-Ca-Sr-Si-ON: Eu, Z series, Sr-Mg-Si-ON: Eu, Z series, Ca-Zn-Si-CN: Eu, Z-based, Sr-Zn-Si-CN: Eu, Z-based, Sr-Ca-Zn-Si-CN: Eu, Z-based, Ca-Zn-Si-CN- Eu: Z System, Sr—Zn—Si—C—O—N: Eu, Z system, Sr—Ca—Zn—Si—C—O—N: Eu, Z system, Mg—Zn—Si—N: Eu, Z system Mg-Ca-Zn-Sr-Si-N: Eu, Z system, Sr-Zn-Mg-Si-N: Eu, Z system, Mg-Zn-Si-O-N: Eu, Z system, Mg- Ca-Zn-Sr-Si-ON: Eu, Z system, Sr-Mg-Zn-Si-ON: Eu, Z system, Ca-Zn-Si-Sn-CN: Eu, Z system , Sr-Zn-Si-S -CN: Eu, Z system, Sr-Ca-Zn-Si-Sn-CN: Eu, Z system, Ca-Zn-Si-Sn-C-O-N: Eu, Z system, Sr- Zn—Si—Sn—C—O—N: Eu, Z series, Sr—Ca—Zn—Si—Sn—C—O—N: Eu, Z series, Mg—Zn—Si—Sn—N: Eu, Z-based, Mg-Ca-Zn-Sr-Si-Sn-N: Eu, Z-based, Sr-Zn-Mg-Si-Sn-N: Eu, Z-based, Mg-Zn-Si-Sn-O-N : Eu, Z series, Mg-Ca-Zn-Sr-Si-Sn-ON: Eu, Z series, Sr-Mg-Zn-Si-Sn-ON: Various combinations such as Eu, Z series A phosphor can be manufactured. Z, which is a rare earth element, preferably contains at least one of Y, La, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, and Lu, but Sc, Sm, Tm, Yb may be contained. These rare earth elements are mixed in the raw material in the form of oxides, imides, amides, etc. in addition to simple substances. Rare earth elements mainly have a stable trivalent electron configuration, while Yb, Sm, etc. have a divalent configuration, and Ce, Pr, Tb, etc. have a tetravalent electron configuration. When the rare earth element of the oxide is used, the involvement of oxygen affects the light emission characteristics of the phosphor. In other words, the emission luminance may be reduced by containing oxygen. On the other hand, there are also advantages such as shortening the afterglow. However, when Mn is used, the particle size can be increased by the flux effect of Mn and O, and the luminance can be improved.
For example, La is used as a coactivator. Since lanthanum oxide (La ₂ O ₃ ) is a white crystal and is quickly replaced with carbonate when left in the air, it is stored in an inert gas atmosphere.
For example, Pr is used as a coactivator. Praseodymium oxide (Pr ₆ O ₁₁ ) is a non-stoichiometric oxide, unlike ordinary rare earth oxide Z ₂ O _3, and burns praseodymium oxalate, hydroxide, carbonate, etc. in the air 800 When heated to 0 ° C., it is obtained as a black powder having a composition of Pr ₆ O ₁₁ . Pr ₆ O ₁₁ is a starting material for synthesizing a praseodymium compound, and a high-purity one is also commercially available.

In particular, the phosphor according to the present invention includes Mn-added Sr—Ca—Si—N: Eu, Ca—Si—N: Eu, Sr—Si—N: Eu, Sr—Ca—Si—O—N: Eu, Ca-Si-ON: Eu, Sr-Si-ON: Eu-based silicon nitride. The basic constituent elements of this phosphor are represented by the general formula L _X Si _Y N _{(2 / 3X + 4 / 3Y)} : Eu or L _X Si _Y O _Z N _{(2 / 3X + 4 / 3Y-2 / 3Z)} : Eu (L is Sr, Ca, or any one of Sr and Ca.) In the general formula, X and Y are preferably X = 2, Y = 5, or X = 1, Y = 7, but any can be used. Specifically, the basic constituent elements, Mn is added _{(Sr X Ca 1-X)} 2 Si 5 N 8: Eu, Sr 2 Si 5 N 8: Eu, Ca 2 Si 5 N 8: Eu, Sr _{X Ca 1-X Si 7 N} 10: Eu, SrSi 7 N 10: Eu, CaSi 7 N 10: it is preferable to use a phosphor represented by Eu, during the composition of the phosphor, Mg, At least one selected from the group consisting of Sr, Ca, Ba, Zn, B, Al, Cu, Mn, Cr and Ni may be contained. However, the present invention is not limited to this embodiment and examples.
L is any one of Sr, Ca, Sr and Ca. The mixing ratio of Sr and Ca can be changed as desired.
By using Si for the composition of the phosphor, it is possible to provide an inexpensive phosphor with good crystallinity.

Europium Eu, which is a rare earth element, is used for the emission center. Europium mainly has bivalent and trivalent energy levels. The phosphor of the present invention uses Eu ²⁺ as an activator with respect to the base alkaline earth metal silicon nitride. Eu ²⁺ is easily oxidized and is commercially available with a trivalent Eu ₂ O ₃ composition. However, in commercially available Eu ₂ O ₃ , O is greatly involved and it is difficult to obtain a good phosphor. Therefore, it is preferable to use a material obtained by removing O from Eu ₂ O ₃ out of the system. For example, it is preferable to use europium alone or europium nitride. However, this is not the case when Mn is added.

_{Sr 2 Si 5 N 8: Eu} , Pr, Ba 2 Si 5 N 8: Eu, Pr, Mg 2 Si 5 N 8: Eu, Pr, Zn 2 Si 5 N 8: Eu, Pr, SrSi 7 N 10: Eu _{, Pr, BaSi 7 N 10:} Eu, Ce, MgSi 7 N 10: Eu, Ce, ZnSi 7 N 10: Eu, Ce, Sr 2 Ge 5 N 8: Eu, Ce, Ba 2 Ge 5 N 8: Eu, _{Pr, Mg 2 Ge 5 N 8} : Eu, Pr, Zn 2 Ge 5 N 8: Eu, Pr, SrGe 7 N 10: Eu, Ce, BaGe 7 N 10: Eu, Pr, MgGe 7 N 10: Eu, Pr _{, ZnGe 7 N 10: Eu,} Ce, Sr 1.8 Ca 0.2 Si 5 N 8: Eu, Pr, Ba 1.8 Ca 0.2 Si 5 N 8: Eu, Ce, Mg 1.8 Ca 0 _.2 Si ₅ N ₈ : Eu, Pr, Zn _1.8 Ca _0.2 Si ₅ N ₈ : Eu, Ce, Sr _0.8 Ca _0.2 Si ₇ N ₁₀ : Eu, La, Ba _0.8 Ca _0.2 Si ₇ N _{10: Eu, La, Mg 0.8} Ca 0.2 Si 7 N 10: Eu, Nd, Zn 0.8 Ca 0.2 Si 7 N 10: Eu, Nd, Sr 0.8 Ca 0.2 Ge 7 _{N 10: Eu, Tb, Ba} 0.8 Ca 0.2 Ge 7 N 10: Eu, Tb, Mg 0.8 Ca 0.2 Ge 7 N 10: Eu, Pr, Zn 0.8 Ca 0.2 Ge ₇ N ₁₀ : Eu, Pr, Sr _0.8 Ca _0.2 Si ₆ GeN ₁₀ : Eu, Pr, Ba _0.8 Ca _0.2 Si ₆ GeN ₁₀ : Eu, Pr, Mg _0.8 Ca _{0.2 Si 6 GeN 10: Eu, Y} , Zn 0.8 Ca 0.2 Si _{GeN 10: Eu, Y, Sr} 2 Si 5 N 8: Pr, Ba 2 Si 5 N 8: Pr, Sr 2 Si 5 N 8: Tb, BaGe 7 N 10: Ce , etc. can be manufactured without limitation.

Mn as an additive promotes diffusion of Eu ²⁺ and improves luminous efficiency such as luminous luminance, energy efficiency, and quantum efficiency. Mn is contained in the raw material, or Mn alone or a Mn compound is contained in the manufacturing process and fired together with the raw material. However, Mn is not contained in the basic constituent elements after firing, or even if contained, only a small amount remains compared to the initial content. This is probably because Mn was scattered in the firing step.
The phosphor includes Mg, Ga, In, Li, Na, K, Re, Mo, Fe, Sr, Ca, Ba, Zn, B, Al, Cu, in the basic constituent element or together with the basic constituent element. It contains at least one selected from the group consisting of Mn, Cr, O and Ni. These elements have actions such as increasing the particle diameter and increasing the luminance of light emission. Further, B, Al, Mg, Cr and Ni have an effect that afterglow can be suppressed.

  Such a nitride-based phosphor absorbs part of the blue light emitted by the LED chip and emits light in the yellow to red region. Using a nitride-based phosphor together with a YAG-based phosphor in a light-emitting device having the above-described configuration, the blue light emitted by the LED chip and the yellow to red light by the nitride-based phosphor are mixed to produce a warm color system. Provided is a light-emitting device that emits white mixed-color light. It is preferable that the phosphor added in addition to the nitride-based phosphor contains an yttrium / aluminum oxide phosphor activated with cerium. This is because it can be adjusted to a desired chromaticity by containing the yttrium aluminum oxide phosphor. The yttrium / aluminum oxide phosphor activated with cerium absorbs part of the blue light emitted by the LED chip and emits light in the yellow region. Here, the blue light emitted by the LED chip and the yellow light of the yttrium / aluminum oxide fluorescent material emit light blue-white by mixing colors. Therefore, the yttrium / aluminum oxide phosphor and the phosphor emitting red light are mixed together in a translucent coating member and combined with the blue light emitted by the LED chip to mix white color. A light-emitting device that emits light can be provided. Particularly preferred is a white light emitting device whose chromaticity is located on the locus of black body radiation in the chromaticity diagram. However, in order to provide a light emitting device having a desired color temperature, the amount of phosphor of the yttrium / aluminum oxide phosphor and the amount of phosphor of red light emission can be appropriately changed. This light-emitting device that emits white-based mixed color light improves the special color rendering index R9. A conventional white light emitting device consisting only of a combination of a blue light emitting element and an yttrium aluminum oxide phosphor activated with cerium has a special color rendering index R9 of almost 0 at a color temperature of Tcp = 4600K, and a reddish component. Was lacking. For this reason, increasing the special color rendering index R9 has been a problem to be solved. However, in the present invention, the special color rendering index near the color temperature Tcp = 4600K is obtained by using the phosphor emitting red light together with the yttrium aluminum oxide phosphor. R9 can be increased to around 40.

Next, the phosphor according to the present invention: is described a method of manufacturing the _{((Sr X Ca 1-X} ) 2 Si 5 N 8 Eu), but is not limited to this manufacturing method. The phosphor contains Mn and O.

Raw materials Sr and Ca are pulverized. The raw materials Sr and Ca are preferably used alone, but compounds such as imide compounds and amide compounds can also be used. The raw materials Sr and Ca may contain B, Al, Cu, Mg, Mn, MnO, Mn ₂ O ₃ , Al ₂ O ₃ and the like. The raw materials Sr and Ca are pulverized in a glove box in an argon atmosphere. Sr and Ca obtained by pulverization preferably have an average particle diameter of about 0.1 μm to 15 μm, but are not limited to this range. The purity of Sr and Ca is preferably 2N or higher, but is not limited thereto. In order to improve the mixed state, at least one of the metal Ca, the metal Sr, and the metal Eu can be alloyed, nitrided, pulverized, and used as a raw material.

The raw material Si is pulverized. The raw material Si is preferably a simple substance, but a nitride compound, an imide compound, an amide compound, or the like can also be used. For example, Si ₃ N ₄ , Si (NH ₂ ) ₂ , Mg ₂ Si, or the like. The purity of the raw material Si is preferably 3N or more, but Al ₂ O ₃ , Mg, metal borides (Co ₃ B, Ni ₃ B, CrB), manganese oxide, H ₃ BO ₃ , B ₂ O ₃ , Compounds such as Cu ₂ O and CuO may be contained. Si is also pulverized in a glove box in an argon atmosphere or a nitrogen atmosphere in the same manner as the raw materials Sr and Ca. The average particle size of the Si compound is preferably about 0.1 μm to 15 μm.

  Next, the raw materials Sr and Ca are nitrided in a nitrogen atmosphere. This reaction formula is shown in the following formula 1 and formula 2, respectively.

3Sr + N ₂ → Sr ₃ N ₂ (Formula 1)
3Ca + N ₂ → Ca ₃ N ₂ (Formula 2)
Sr and Ca are nitrided in a nitrogen atmosphere at 600 to 900 ° C. for about 5 hours. Sr and Ca may be mixed and nitrided, or may be individually nitrided. Thereby, a nitride of Sr and Ca can be obtained. Sr and Ca nitrides are preferably of high purity, but commercially available ones can also be used.

  The raw material Si is nitrided in a nitrogen atmosphere. This reaction formula is shown in the following formula 3.

3Si + 2N ₂ → Si ₃ N ₄ (Formula 3)
Silicon Si is also nitrided in a nitrogen atmosphere at 800 to 1200 ° C. for about 5 hours. Thereby, silicon nitride is obtained. The silicon nitride used in the present invention is preferably highly pure, but commercially available ones can also be used.

Sr, Ca or Sr—Ca nitride is pulverized. Sr, Ca, and Sr—Ca nitrides are pulverized in a glove box in an argon atmosphere or a nitrogen atmosphere.
Similarly, Si nitride is pulverized. Similarly, the Eu compound Eu ₂ O ₃ is pulverized. Europium oxide is used as the Eu compound, but metal europium, europium nitride, and the like can also be used. In addition, as the raw material Z, an imide compound or an amide compound can be used. Europium oxide is preferably highly purified, but commercially available products can also be used. The average particle size of the alkaline earth metal nitride, silicon nitride and europium oxide after pulverization is preferably about 0.1 μm to 15 μm.

The raw material may contain at least one selected from the group consisting of Mg, Sr, Ca, Ba, Zn, B, Al, Cu, Mn, Cr, O, and Ni. In addition, the above elements such as Mg, Zn, and B can be mixed by adjusting the blending amount in the following mixing step. These compounds can be added alone to the raw material, but are usually added in the form of compounds. Such compounds include H ₃ BO ₃ , Cu ₂ O ₃ , MgCl ₂ , MgO · CaO, Al ₂ O ₃ , metal borides (CrB, Mg ₃ B ₂ , AlB ₂ , MnB), B ₂ O ₃ , Cu ₂ O, CuO, and the like.

After the pulverization, Sr, Ca, Sr—Ca nitride, Si nitride, and Eu compound Eu ₂ O ₃ are mixed, and Mn is added. Since these mixtures are easily oxidized, they are mixed in a glove box in an Ar atmosphere or a nitrogen atmosphere.

Finally, a mixture of Sr, Ca, Sr—Ca nitride, Si nitride, and Eu compound Eu ₂ O ₃ is fired in an ammonia atmosphere. A phosphor represented by (Sr _X Ca _1-X ) ₂ Si ₅ N ₈ : Eu to which Mn is added can be obtained by firing. However, the composition of the target phosphor can be changed by changing the blending ratio of each raw material.

For firing, a tubular furnace, a small furnace, a high-frequency furnace, a metal furnace, or the like can be used. The firing temperature can be in the range of 1200 to 1700 ° C, but the firing temperature is preferably 1400 to 1700 ° C. It is preferable to use a one-step baking in which the temperature is gradually raised and the baking is performed at 1200 to 1500 ° C. for several hours, but the first baking is performed at 800 to 1000 ° C. and the heating is gradually started from 1200. Two-stage firing (multi-stage firing) in which the second stage firing is performed at 1500 ° C. can also be used. The phosphor material is preferably fired using a boron nitride (BN) crucible or boat. Besides the crucible made of boron nitride, a crucible made of alumina (Al ₂ O ₃ ) can also be used.

  By using the above manufacturing method, it is possible to obtain a target phosphor.

In the embodiment of the present invention, a nitride-based phosphor is used as the phosphor that emits reddish light. In the present invention, the above-described YAG-based phosphor can emit red light. It is also possible to provide a light emitting device including a simple phosphor. Such a phosphor capable of emitting red light is a phosphor that emits light when excited by light having a wavelength of 400 to 600 nm. For example, Y ₂ O ₂ S: Eu, La ₂ O ₂ S: Eu. CaS: Eu, SrS: Eu, ZnS: Mn, ZnCdS: Ag, Al, ZnCdS: Cu, Al and the like. Thus, by using a phosphor capable of emitting red light together with a YAG phosphor, it is possible to improve the color rendering properties of the light emitting device.

  The phosphors capable of emitting red light typified by the aluminum garnet-based phosphor and nitride-based phosphor formed as described above are included in two wavelength conversion members in the vicinity of the light-emitting element. One or more types may be present, or one type or two or more types may be present in the two-layer wavelength conversion member. With such a configuration, it is possible to obtain mixed color light by mixing light from different types of phosphors. In this case, it is preferable that the average particle diameters and shapes of the phosphors are similar in order to better mix the light emitted from the phosphors and reduce color unevenness. Also, considering that the nitride-based phosphor absorbs part of the light that has been wavelength-converted by the YAG-based phosphor, the nitride-based phosphor is disposed closer to the light emitting element than the YAG-based phosphor. It is preferable to form the wavelength conversion member as described above. With this configuration, a part of the light wavelength-converted by the YAG phosphor is not absorbed by the nitride phosphor, and the YAG phosphor and the nitride phosphor are mixed. Compared with the case where it contains, the color rendering property of mixed-color light can be improved.

(Alkaline earth metal salt)
The light-emitting device in this embodiment mode uses alkaline earth activated by europium as a phosphor that absorbs part of light emitted from a light-emitting element and emits light having a wavelength different from the wavelength of the absorbed light. It can also have a metal silicate. The alkaline earth metal silicate is preferably an alkaline earth metal orthosilicate represented by the following general formula.
(2-x-y) SrO · x (Ba, Ca) O · (1-a-b-c-d) SiO 2 · aP 2 O 5 bAl 2 O 3 cB 2 O 3 dGeO 2: yEu 2+ ( Equation Medium, 0 <x <1.6, 0.005 <y <0.5, 0 <a, b, c, d <0.5.)
(2-x-y) BaO · x (Sr, Ca) O · (1-a-b-c-d) SiO 2 · aP 2 O 5 bAl 2 O 3 cB 2 O 3 dGeO 2: yEu 2+ ( Equation (Inside, 0.01 <x <1.6, 0.005 <y <0.5, 0 <a, b, c, d <0.5.)
Here, preferably, at least one of the values of a, b, c and d is greater than 0.01.

The light-emitting device in the present embodiment is a phosphor composed of an alkaline earth metal salt. In addition to the alkaline earth metal silicate described above, alkaline earth metal aluminate or Y activated by europium and / or manganese is used. (V, P, Si) O ₄ : Eu, or an alkaline earth metal-magnesium-disilicate represented by the following formula:

Me (3-xy) MgSi ₂ O ₃ : xEu, yMn (wherein 0.005 <x <0.5, 0.005 <y <0.5, Me represents Ba and / or Sr and / or Or Ca.)
Next, the manufacturing process of the phosphor made of alkaline earth metal silicate in the present embodiment will be described.

  For the production of alkaline earth metal silicates, the stoichiometric amounts of the starting materials alkaline earth metal carbonate, silicon dioxide and europium oxide are intimately mixed according to the selected composition, and the phosphor is produced. In a conventional solid reaction, the desired phosphor is converted at a temperature of 1100 ° C. and 1400 ° C. under a reducing atmosphere. At this time, it is preferable to add less than 0.2 mol of ammonium chloride or other halide. If necessary, part of silicon can be replaced with germanium, boron, aluminum, and phosphorus, and part of europium can be replaced with manganese.

One of the phosphors as described above, ie, alkaline earth metal aluminates activated with europium and / or manganese, Y (V, P, Si) O ₄ : Eu, Y ₂ O ₂ S: Eu ³⁺ By combining one or these phosphors, an emission color having a desired color temperature and high color reproducibility can be obtained.

[Conductive wire 104]
Connection between the conductor wiring 105 formed in the package recess and the electrode of the LED chip 103 can be performed by making the electrode of the LED chip 103 face the conductor wiring 105 through a conductive wire or a conductive member. . The conductive wire 104 is a kind of electrical connection member that connects the electrode of the LED chip 103 and the conductor wiring 105 provided in the ceramic package, and has ohmic properties, mechanical connectivity, electrical conductivity, and heat. What has good conductivity is required. The thermal conductivity is preferably 0.01 cal / cm ² / cm / ° C. or higher, more preferably 0.5 cal / cm ² / cm / ° C. or higher. In consideration of workability and the like, the diameter of the conductive wire is preferably Φ10 μm or more and Φ45 μm or less. Specific examples of such conductive wires include conductive wires using metals such as gold, copper, platinum, and aluminum, and alloys thereof. Such a conductive wire can easily connect an electrode of each LED chip and a conductive pattern provided on the substrate by a wire bonding device. Examples according to the present invention will be described in detail below. Needless to say, the present invention is not limited to the following examples.

  A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic top view of a light emitting device using a ceramic package according to the present embodiment. 2 is a cross-sectional view taken along the line C-C ′ of FIG.

  The ceramic package according to the present embodiment includes a ceramic base portion 202 serving as a substrate, a ceramic base portion 204 having a shape that widens in the opening direction, and a ceramic base provided between the ceramic base portion 202 and the ceramic base portion 204. Part 203 and a ceramic base part 205 having a stepped shape in the opening of the package. The ceramic base portion 202 serving as a substrate has a through hole, and a conductor wiring 105 for supplying power to the LED chip 103 extends from the bottom surface of the concave portion of the package to the mounting surface side of the light emitting device via the through roll. Yes. Further, the conductor wiring extending to the mounting surface side of the light emitting device is connected to the external electrode. The ceramic base portion 204 has a shape that becomes wider toward the opening direction, has an inner wall that forms a recess of the package, and the light reflecting portion 102 is provided on the inner wall. The ceramic base portion 203 insulates and separates the light reflecting portion 102 from the conductor wiring 105, and the exposed inner wall surface is adjacent to the bottom surface of the package recess. The ceramic base portion 205 has an opening having an inner diameter larger than the inner diameter of the ceramic base portion 204 and forms a step in the opening portion of the ceramic package such that a part of the ceramic base portion 204 is exposed. In addition, the light emitting device according to the present embodiment includes the first ceramic base portion 106a exposed around the light reflecting portion 102 when viewed from the main surface direction of the light emitting device. The first ceramic base portion 106 a is formed by the upper surface of the ceramic base portion 204 and the wall surface of the ceramic base portion 205. Further, as shown in FIG. 2, a mold member for sealing the inside of the recess covers the light reflecting portion 102 and the first ceramic base portion 106a.

  The conductor wiring 105 is first formed by screen-printing a resin paste (viscosity of about 30000 ps) containing tungsten (average particle diameter of about 1 μm), and the surface is further covered with Ag. The conductor wiring 105 is connected to the conductor wiring 105 on the mounting surface side of the ceramic package through the through hole 201 of the ceramic substrate 202. By doing so, light from the LED chip 103 is reflected on the surface of the conductor wiring 105 and travels in the opening direction of the package, so that the light extraction efficiency of the light emitting device can be improved.

  The LED chip 103 is fixed to the surface of the conductor wiring 105 provided on the bottom of the recess of the package via an insulating adhesive. Further, the first ceramic base portion 106 a, the light reflecting portion 102, the conductor wiring 105, the conductive wire 104, and the LED chip 103 are sealed with a mold member 107.

  Hereinafter, formation of the ceramic package according to the present example will be described. A green sheet mainly composed of alumina is cut out to a predetermined size, and a 0.3 mφ through hole 201 is formed by a normal method using a punching machine. Next, the hole of the through hole 201 is filled with a tungsten conductor paste by screen printing from the mounting surface side of the light emitting device, and the portion of the conductor wiring 105 is printed. Finally, the surface of the conductor wiring 105 on the side where the LED chip 103 is placed is covered with Ag, and a green sheet to be fired as the ceramic substrate 202 is formed.

  Next, a green sheet in which a through hole having a size capable of accommodating the conductor wiring and the LED chip is provided by a punching machine is formed. The formed green sheet becomes a ceramic base portion formed inside the light reflecting portion when viewed from the light emission observation surface direction. The green sheet is also provided for electrical insulation between the first metal layer and the conductor wiring pattern.

  Next, a green sheet having a through hole whose inner diameter is widened in one opening direction is formed by cutting. The formed green sheet becomes a ceramic base portion 204 having the light reflecting portion 102. Further, a green sheet having a through hole having an inner diameter larger than the maximum inner diameter of the ceramic base portion 204 is formed. The formed green sheet becomes the ceramic base portion 205 formed outside the light reflecting portion 102. The inner wall surface of the ceramic base portion 205 forms a step-like first ceramic base portion 106 a at the opening of the recess together with the upper surface of the ceramic base portion 204.

  A plurality of green sheets formed as described above are stacked in a state where the centers of the through holes are aligned, and heated and pressed in a vacuum to temporarily form an opening of the package. After the opening is formed, a tungsten resin paste that constitutes the first metal layer is applied to a part of the inner wall of the opening. For the first metal layer, tungsten particles similar to those used for the wiring layer are used. In order to electrically insulate the first metal layer from the conductor wiring pattern, the green sheet is configured to have a thickness of about 150 μm so that the reflectance does not decrease.

  By sintering this, a ceramic package having a first metal layer is formed. Next, a Ni / Ag multilayer film is electroplated on the exposed surfaces of the first metal layer and the conductor wiring pattern as the second metal layer, respectively. As a result, a ceramic package having an opening diameter of 2.0 mmφ and an opening depth of 0.8 mm is formed. For electrical extraction from the ceramic package with the external electrode, a connection pin made of metal Kovar is formed by silver solder connection.

On the other hand, an LED which is a semiconductor light emitting element is an InGaN semiconductor having a main light emission peak of 450 nm. For LED chips, a TMG (trimethylgallium) gas, TMI (trimethylindium) gas, nitrogen gas, and a dopant gas are allowed to flow along with a carrier gas on a cleaned sapphire substrate, and a gallium nitride compound semiconductor film is formed by MOCVD. To form. By switching between SiH ₄ and Cp ₂ Mg as dopant gases, a gallium nitride semiconductor having N-type conductivity and a gallium nitride semiconductor having P-type conductivity are formed to form a PN junction. (The P-type semiconductor is annealed at 400 ° C. or higher after film formation.)
After exposing the surface of each PN semiconductor by etching, each electrode is formed by sputtering. After a scribe line is drawn on the semiconductor wafer thus completed, it is divided by an external force to form an LED chip as a light emitting element. The LED chip 103 capable of emitting blue light is die-bonded to a predetermined bottom in the ceramic package opening with an epoxy resin, and then fixed by thermosetting. Thereafter, using a gold wire as the conductive wire 104, electrical connection is established by wire-bonding each electrode of the LED chip to the conductor wiring 105 on the ceramic base portion 202. Silicone resin is injected into the recess in which the LED chip is disposed as a forming material of the mold member 107. At this time, the silicone resin is injected so as to be on the first ceramic base portion 106 a and the light reflecting portion 102. After the injection, the silicone resin is cured at 150 ° C. for 1.5 hours, and the mold member 107 is formed on the first ceramic base portion 106 a and the light reflecting portion 102.

  With the light emitting device of the present embodiment, the stress acting between the mold member and the light reflecting portion is relieved by the stress acting between the mold member and the first ceramic base portion. Thus, a light emitting device with high luminance and high reliability can be obtained without dropping from the case.

  A second embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic top view of a light emitting device using a ceramic package according to the present embodiment. 2 is a cross-sectional view taken along the line C-C ′ of FIG.

  The ceramic package in the present embodiment is seen from the main surface direction of the light emitting device, the first ceramic base portion 106a exposed around the light reflecting portion 102, and the LED chip 103 exposed inside the light reflecting portion 102. And a second ceramic base portion 106b provided so as to surround. The second ceramic base portion 106 b is formed by the exposed surfaces of the ceramic base portions 202 and 203. Further, as shown in FIG. 2, the first ceramic base portion 106a and the second ceramic base portion 106b are configured to have at least a pair of substantially parallel surfaces. In the present embodiment, a pair of substantially parallel surfaces is provided in a direction parallel to the plane of the ceramic substrate 202 serving as a substrate and a pair in a direction perpendicular to the same plane. Such substantially parallel surfaces can be easily formed as a part of the shape of the wall surface of the ceramic green sheet laminated body because the ceramic package is formed by firing a laminated body of ceramic green sheets. Further, as shown in FIG. 2, a mold member for sealing the inside of the concave portion of the ceramic package is provided so as to cover substantially parallel surfaces of the first ceramic base portion 106a and the second ceramic base portion 106b. It has been. Here, the stress acting between the mold member and the substantially parallel surfaces of the first and second ceramic base parts is configured to cancel out the stress acting between the mold member and the light reflecting part. Further, by providing two pairs of parallel surfaces in the above-described direction, stress from various directions can be relieved. The light emitting device is the same as that of Example 1 except for the configuration described above. By using the light emitting device of this embodiment, the stress acting between the mold member and the light reflecting portion is relieved by the stress acting between the mold member and the substantially parallel surfaces of the first and second ceramic base portions. Therefore, the light emitting device with high reliability can be obtained without dropping the mold member from the ceramic package.

  A third embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a schematic perspective view of a light emitting device using a ceramic package according to the present embodiment. 5 is a cross-sectional view taken along line XX shown in FIG.

  In the present embodiment, the vicinity of the opening of the concave portion of the ceramic package is shaped such that the inner diameter of the ceramic base portion 205 is reduced stepwise, and the end portion of the ceramic base portion 205 is positioned above the second light reflecting portion 102b. Thus, the first ceramic base portion 106a is formed. Further, a ceramic base portion 202 serving as a substrate is exposed at the center of the bottom surface of the recess, and the LED chip is directly fixed to the exposed ceramic base portion 202 via an insulating adhesive. Therefore, the configuration is different from the above-described embodiment in which the LED chip is fixed to the conductor wiring via the insulating adhesive. By directly fixing to the ceramic substrate in this manner, the fixing strength of the light emitting element to the package can be improved as compared with the case of fixing to the conductor wiring via the insulating adhesive. Of the ceramic base portion 202 exposed on the bottom surface of the concave portion, the portion other than the portion where the insulating adhesive is disposed is the second ceramic base portion 106b provided inside the first light reflecting portion 102a, and emits light. Surround the element. Further, the light reflecting portion in the present embodiment includes the first light reflecting portion 102a provided around the light emitting element and the second light reflecting portion 102b provided on the inner wall of the ceramic base portion 204 forming the recess. Become. Here, the second ceramic base portion 106b is also provided inside the second light reflecting portion 102b. Further, the second light reflecting portion 106b in the present embodiment also serves as a conductor wiring, and a protection element 401 that protects the LED chip 103 from destruction due to overvoltage is placed with its back electrode facing. Further, when viewed from the main surface side of the light emitting device, a part of the ceramic base portion 202 is exposed between the first light reflecting portion 102a and the conductor wiring provided in the vicinity of the concave portion side wall on the bottom surface of the concave portion. . The exposed ceramic base portion improves the adhesion between the mold member and the ceramic package, and can prevent the mold member from peeling off the package. The conductor wiring provided in the vicinity of the side wall of the recess is provided as a pair of positive and negative, and is connected to the electrode of the LED chip 103 via the conductive wire 104.

  In addition, when a sintered body of a ceramic green sheet having a plurality of through holes in which conductor wiring is formed on the inner wall is cut into individual ceramic packages, cutting is performed at a position connecting the centers of the through holes. Thereby, the conductor wiring which passes between the ceramic base part 202 and the ceramic base part 203 from the inside of the recess and is exposed to the side surface of the ceramic package is obtained. With this configuration, the light emitting device according to the present embodiment emits light in a direction parallel to the mounting surface when mounted through a conductive member so that the side surface of the ceramic package faces the external wiring board. You can also

  The mold member 107 in this embodiment includes a lower surface of the end portion of the ceramic base portion 205 protruding into the recess of the first ceramic base portion 106a, the first and second light reflecting portions 102a and 102b, The second ceramic base portion 106b is covered at least. Other than the above configuration, the configuration is the same as that of the above-described embodiment.

  By using the light emitting device of this embodiment, the stress acting between the mold member 107 and the light reflecting portion is relieved by the adhesive force acting between the mold member and the surface on which the stepped ceramic base portion is formed. The light emitting device with high reliability can be obtained without peeling the mold member from the ceramic package.

  A fourth embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a schematic perspective view of a light emitting device using a ceramic package according to the present embodiment. FIG. 7 is a cross-sectional view of the ceramic package taken along the line XX shown in FIG.

  The ceramic package in the present embodiment has the first light reflecting portion 102a on the bottom surface of the recess, and the first ceramic base portion 106a around the first light reflecting portion 102a. In particular, the first ceramic base portion 106 a in the present embodiment includes the exposed wall surface of the ceramic base portion 203. The first light reflecting portion 102a reflects light emitted from the side surface direction of the light emitting element toward the light emission observation surface, and also serves as a pair of positive and negative conductor wirings connected to the light emitting element to supply electric power. The first ceramic base portion 106a is provided between the second light reflecting portion 102b provided on the inner wall surface of the recess that becomes wider in the opening direction and the first light reflecting portion 102a provided on the bottom surface of the recess. The two are insulated and separated. The mold member 107 includes a first ceramic base portion 106a, a second ceramic base portion 106b that insulates and separates the pair of positive and negative conductor wires and at least partially surrounds the LED chip 103, and a first light reflecting portion 102a. At least the third ceramic base portion 106c surrounded by the first and second light reflecting portions 102a and 102b. In addition, the mold member 107 in a present Example is made into the shape which coat | covers the 2nd light reflection part 102b. However, in consideration of the effect of the stress acting between the mold member 107 and the light reflecting portion, the mold member 107 is disposed apart from the second light reflecting portion 102b and does not cover the second light reflecting portion 102b. It can also be a shape.

  Further, unlike the package of the third embodiment having the ceramic base portion 205, the ceramic package in the present embodiment has the second light reflecting portion 102b formed continuously from the inner wall surface to the upper surface of the ceramic base portion 204. Therefore, the ceramic base portion that is covered with the mold member in the recess is not exposed outside the second light reflecting portion 102b when viewed from the light emission observation surface direction. That is, it is different from the third embodiment in which the first ceramic base portion contributing to the relaxation of the stress acting between the mold member and the light reflecting portion is provided outside the light reflecting portion provided on the inner wall widened in the opening direction. It is a configuration. However, in the ceramic package according to the present embodiment, the stress acting between the mold member and the light reflecting portion is relieved by the adhesive force between the ceramic base portion exposed at the bottom of the recess and the mold member.

  That is, the ceramic package in the present embodiment includes a second ceramic base portion 106b that insulates and separates the pair of positive and negative conductor wirings and at least partially surrounds the LED chip 103 at the bottom of the recess, and a first light reflecting portion. And a third ceramic base portion 106c that is surrounded by 102a and at least partially surrounds the LED chip 103. Here, the shape of the second ceramic base portion 106b and the third ceramic base portion 106c is such that at least a part thereof is symmetrical with respect to the light emitting element when viewed from the light emission observation plane direction. For example, as shown in FIG. 6, as a polygonal shape having sides substantially parallel to the outer edge of the LED chip 103 placed in the center of the recess, a region where no light reflecting portion is formed is provided in the ceramic base portion 202. A third ceramic base portion 106c is formed. Further, a second ceramic base portion 106 b including a shape symmetrical to the polygonal shape is formed on the other side of the LED chip 103. In general, the adhesion between the mold member and the ceramic substrate is stronger than the adhesion at the interface between the mold member and the light reflecting portion. On the other hand, the shape of the second and third ceramic base parts as in the present embodiment allows the mold member and the ceramic base part to be evenly contacted in each orientation of the LED chip 103, and the adhesive force between them. Works equally in each direction. Accordingly, the mold member is not peeled off from the ceramic package, so that a highly reliable light-emitting device can be obtained.

  The LED chip 103 is fixed to the first light reflecting portion 102 a that also serves as a conductor wiring by an insulating adhesive 402. On the other hand, the protective element 401 that protects the LED chip 103 from destruction due to overvoltage is fixed so that the back electrode is connected to the first light reflecting portion 102a via a conductive member. Other than the above configuration, the configuration is the same as that of the fourth embodiment described above.

  By adopting the light emitting device of the present embodiment, the stress acting between the mold member and the light reflecting portion is relieved by the adhesion between the mold member and the ceramic base portion, so that the mold member does not fall out of the ceramic package. A light-emitting device with high reliability can be obtained.

  The light emitting device according to this embodiment is formed in the same manner as in the above-described embodiment except that a fluorescent material is contained in the mold member.

The fluorescent material is prepared by co-precipitation with oxalic acid of a solution obtained by dissolving a rare earth element of Y, Gd, and Ce in an acid at a stoichiometric ratio with oxalic acid, and calcining the mixture, and then mixing aluminum oxide. To obtain mixed raw materials. Further, barium fluoride is mixed as a flux, then packed in a crucible, and fired in air at a temperature of 1400 ° C. for 3 hours to obtain a fired product. The fired product is ball _milled in water, washed, separated, dried, and finally passed through a sieve to have a center particle size of 8 μm (Y _0.995 Gd _0.005 ) _2.750 Al ₅ O ₁₂ : Ce _0.250 phosphor Form.

  The silicone resin composition (refractive index: 1.53) contains 5.5 wt% of the fluorescent material (refractive index: 1.84), and is stirred for 5 minutes with a rotation and revolution mixer. The curable composition thus obtained is filled into the recesses of the ceramic package. Finally, heat treatment is performed at 70 ° C. × 2 hours and 150 ° C. × 1 hour.

  Accordingly, a light-emitting device capable of emitting mixed-color light of light emitted from the light-emitting element and fluorescence of a fluorescent material that absorbs the light and emits light having different wavelengths can be obtained.

FIG. 1 is a schematic top view showing a light emitting device according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing a light emitting device in one embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of a conventional light emitting device shown for comparison with the present invention. FIG. 4 is a schematic perspective view showing a light emitting device according to an embodiment of the present invention. FIG. 5 is a schematic cross-sectional view showing a light emitting device according to an embodiment of the present invention. FIG. 6 is a schematic perspective view showing a light emitting device in one embodiment of the present invention. FIG. 7 is a schematic cross-sectional view showing a light emitting device according to an embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Light-emitting device 102 ... Light reflection part 102a ... 1st light reflection part 102b ... 2nd light reflection part 103, 301 ... LED chip 104 ... Conductive wire 105, 302 ... Conductor wiring 106, 202, 203, 204, 205, 304 ... Ceramic substrate 106a ... First ceramic substrate 106b ... Second ceramic substrate 107, 303 ... Mold Member 201 ... through hole 401 ... protective element 402 ... insulating adhesive

Claims (4)

A wiring layer for electrically connecting the electrodes of the light emitting element from the bottom surface of the concave portion to the lower surface of the insulating base is formed on the insulating base having a concave portion on which the light emitting element is mounted and accommodated, and the inner periphery of the concave portion A light-emitting element storage package having a metal reflective layer deposited on a surface thereof apart from the bottom surface of the recess,
The inner peripheral surface of the concave portion is composed of a vertical surface formed on the bottom surface of the concave portion, and an inclined surface extending outwardly from the upper surface of the insulating base to the upper surface of the insulating base, A package for housing a light emitting element, wherein the package is attached to the inclined surface and not attached to the vertical surface .   The light-emitting element storage package according to claim 1, wherein the insulating base is ceramic.   The light emitting element storage package according to claim 1, wherein the vertical surface is lower than a thickness of the light emitting element. The light emitting element storage package according to any one of claims 1 to 3,
A light-emitting element housed in and mounted in the recess and having an electrode electrically connected to the wiring layer;
A transparent resin covering the light emitting element;
A light emitting device comprising:

Images