JP2014132677A - Light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting device capable of improving both of color shading and light extraction efficiency at the same time.SOLUTION: A first wavelength conversion member 24, a light emitting element 20, and a second wavelength conversion member 26 are sequentially formed on a bottom face of a container toward an opening of a recess 16a away from a side face of the recess via a translucent support member 32. The first wavelength conversion member is a plate-like member formed by compounding an inorganic binder made of an inorganic material and a fluorescent body. A scattering face 18 is formed on the side face of the recess at a portion at which light emitted parallel to a main face of the first wavelength conversion member at least from the side face of the first wavelength conversion member is radiated.

Description

  The present invention relates to a light-emitting device that enables light emission of different colors by mixing light emitted from a light-emitting element with original light even after wavelength conversion.

  A semiconductor light emitting element such as a light emitting diode is small in size, has high power efficiency, and emits bright colors. In addition, the semiconductor light emitting device has the characteristics that there is no fear of a broken ball, etc., excellent initial drive characteristics, and resistance to vibration and repeated on / off lighting. In addition, a light-emitting device that can emit light of various colors based on the principle of light color mixing is developed by combining light emission of a semiconductor light-emitting element and a wavelength conversion member that can emit light of different wavelengths when excited by this. Has been. Such light emitting devices are used as various light sources. In particular, in recent years, it has attracted attention as a next-generation illumination with low power consumption and long life replacing fluorescent lamps, and further improvements in light emission output and light emission efficiency are required. In addition, there is a demand for a high-luminance light source such as a projector such as a car headlight and a floodlight.

  Regarding such a light emitting device, Patent Document 1 proposes a structure shown in FIGS. 9A and 9B. A light emitting semiconductor chip assembly 72 shown in FIG. 9A is configured by fixing a light emitting diode chip 78 on a phosphor chip 74 via a transparent adhesive 76. The phosphor chip 74 has a phosphor layer 82 on a substrate 80 made of a transparent material such as silica or alumina or an opaque material having good light reflectivity. The phosphor layer 82 is configured by dispersing a phosphor in a resin. FIG. 9B shows a cross-sectional view of a light emitting device 92 configured using the light emitting semiconductor chip assembly 72. The light emitting device 92 includes an anode lead 88 and a cathode lead 90, and a light emitting semiconductor chip assembly 72 is fixed to a cup portion 90 a provided at the tip of the cathode lead 90. The anode electrode 84 and the cathode electrode 86 of the light emitting semiconductor chip assembly 72 are connected to the anode lead 88 and the cathode lead 90, respectively. The periphery of the light emitting semiconductor chip assembly 72 is covered with a protective adhesive 96 in which a light scattering agent 94 is dispersed.

JP 2002-141559 A

  According to the light emitting device shown in FIGS. 9A and 9B, since the phosphor chip 74 is fixed to the back surface of the light emitting diode chip 78, the back surface of the light emitting diode chip 78 is connected to the cup portion 90a of the cathode lead. The light output is increased compared to a structure that directly bonds. This is due to the following reason. When the back surface of the light emitting diode chip 78 is directly bonded to the cup portion 90a of the cathode lead with silver paste or the like, light emitted from the back surface of the light emitting diode chip 78 is reflected by the silver paste, but the silver paste has a reflectivity. It is not high, and most of the reflected light returns to the inside of the light emitting diode chip 78 and is absorbed, so that the light output is lowered. By adhering the phosphor chip 74 to the back surface of the light emitting diode chip 78, the ratio of the light emitted from the back surface of the light emitting diode chip 78 returning to the inside of the light emitting diode chip 78 is reduced. Since the light is extracted, the light output is improved. In addition, due to the effect of the light scattering agent 94 dispersed in the protective adhesive 96, the light emission of the light emitting diode chip 78 and the phosphor chip 74 is mixed and color unevenness is suppressed.

  However, such a conventional light emitting device has a problem that it is difficult to obtain a light emitting device that sufficiently satisfies both color unevenness and light emission output. That is, in the light emitting device as shown in FIGS. 9A and 9B, since the phosphor layer 82 for wavelength conversion exists only below the light emitting diode chip 78, the light emitting diode chip 78 emits light from the lower surface. The emitted light passes through the phosphor layer 82 of the phosphor chip 74, but the light emitted from the top and side surfaces of the light emitting diode chip 78 does not pass through the phosphor layer 82. For this reason, uneven color tends to occur. In order to mix the light emission of the light emitting diode chip 78 and the phosphor chip 74 and sufficiently suppress the color unevenness, it is necessary to disperse a large amount of the light scattering agent 94 around the light emitting diode chip 78 and the phosphor chip 74. However, if the light scattering agent 94 is dispersed in a large amount around the light emitting diode chip 78, the light scattered by the light scattering agent 94 easily returns to the inside of the light emitting diode chip 78. The proportion of absorbed light will increase. Further, in the light emitting device as shown in FIGS. 9A and 9B, it is conceivable that the entire periphery of the light emitting diode chip 74 is covered with the phosphor layer 82, but the phosphor particles contained in the phosphor layer 82 are not covered. The light returning to the light emitting diode chip 78 is also generated by the scattering, so that the light absorbed inside the light emitting diode chip 78 also increases. Therefore, when trying to improve the color unevenness, the light extraction efficiency decreases, and it is difficult to improve the color unevenness and the light extraction efficiency at the same time.

  Accordingly, an object of the present invention is to provide a new light emitting device that can simultaneously improve both color unevenness and light extraction efficiency.

In order to achieve the above object, the light-emitting device of the present invention is different from a light-emitting element using a semiconductor as a light-emitting layer and a part of light emission of the light-emitting element in a container having a recess having an upper surface opened. A light emitting device comprising a wavelength conversion member that emits light of a wavelength, and mixing and emitting light emitted from the light emitting element and light emitted from the wavelength conversion member,
The wavelength conversion member has a first wavelength conversion member and a second wavelength conversion member,
On the bottom surface of the container, the first wavelength conversion member, the light emitting element, and the second wavelength conversion member are sequentially directed toward the opening of the recess through a translucent support member. Formed so as to be separated from the side surface of the recess,
The first wavelength conversion member is a plate-like member in which an inorganic binder made of an inorganic material and a phosphor are combined,
A scattering surface is formed on the side surface of the concave portion at least in a portion irradiated with light emitted parallel to the main surface of the first wavelength conversion member from the side surface of the first wavelength conversion member. Features.

  According to the present invention, the first wavelength conversion member, the light emitting element, and the second wavelength conversion member are sequentially formed on the bottom surface of the container via the translucent support member. Light can be extracted efficiently from below. In addition, by forming a first wavelength conversion member made of an inorganic binder and a phosphor below the light emitting element and providing a second wavelength conversion member above the light emitting element, color unevenness can be generated while maintaining high light extraction efficiency. Can be suppressed. That is, the first wavelength conversion member located on the lower side of the light emitting element is a plate-like member in which an inorganic binder and a phosphor are combined. However, the refractive difference between the inorganic binder and the phosphor is relatively small. Light passing through one wavelength conversion member is not scattered much. Therefore, unlike the phosphor layer 82 made of resin and phosphor particles as shown in FIGS. 9A and 9B, the return light to the light emitting element due to scattering in the first wavelength conversion member is Few. On the other hand, since light tends to propagate in the lateral direction inside the plate-like first wavelength conversion member and tends to emit light strongly at the end face of the first wavelength conversion member, uneven color due to this tends to occur. Therefore, by forming a scattering surface in a portion irradiated with light emitted parallel to the main surface of the first wavelength conversion member from at least the side surface of the first wavelength conversion member among the side surfaces of the recess, the first surface is formed. Color unevenness caused by the wavelength conversion member can be suppressed. Since the first wavelength conversion member and the light emitting element are formed apart from the side surface of the concave portion that forms the scattering surface, the return light to the light emitting element by this scattering surface is relatively small. In the present invention, it is possible to provide a light emitting device with improved color unevenness while maintaining high light extraction efficiency due to these effects.

FIG. 1 is a schematic cross-sectional view showing a light emitting device according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view illustrating an example of a light-emitting element used in the light-emitting device of FIG. FIG. 3 is a schematic diagram showing the relationship between the recesses and the light emitting layer. FIG. 4 is a schematic diagram showing the traveling direction of light in the light emitting device shown in FIG. FIG. 5 is a schematic perspective view showing an example of the light emitting device according to Embodiment 1 of the present invention. FIG. 6 is a schematic top view showing an example of the light emitting device according to Embodiment 1 of the present invention. FIG. 7 is a schematic cross-sectional view showing a light-emitting device according to Embodiment 2 of the present invention. FIG. 8 is a schematic cross-sectional view showing a light emitting device according to Embodiment 3 of the present invention. 9A and 9B are schematic cross-sectional views showing a conventional light emitting device.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Each drawing is a schematic diagram, and the arrangement, dimensions, ratio, shape, and the like shown therein may be different from actual ones. Moreover, in each embodiment, the member using the same code | symbol as other embodiment represents the same or corresponding member, and may abbreviate | omit description.

In this specification, the terms “upper” and “lower” are also used as terms indicating the side from which light emission of the light-emitting device is extracted and the opposite side. For example, “upward” refers to the direction in which the light emission of the light emitting device is extracted, and “downward” refers to the opposite direction. Further, the “upper surface” refers to the surface on the side from which light emission of the light emitting device is extracted, and the “lower surface” refers to the surface on the opposite side. The term “inside” with respect to the light emitting device refers to a side close to the light emitting layer of the light emitting element, and the term “outside” refers to the opposite side. In this specification, “translucency” means that the transmittance of the light emitting element at the emission wavelength is 10% or more. “Mixed” light means that two types of light having different chromaticities are spatially mixed so as to be recognized by human eyes as light having new chromaticity. The “refractive index” in the present invention refers to the refractive index at the emission wavelength of the light emitting element.

Embodiment 1
FIG. 1 is a schematic cross-sectional view showing a light emitting device 10 according to Embodiment 1 of the present invention. A light emitting element 20 and a wavelength conversion member 30 that absorbs part of the light emitted from the light emitting element 20 and converts it to a different wavelength are accommodated in a package 16 (accommodator). The package 16 in the present embodiment includes a mounting substrate 12 in which wiring is formed on a flat insulating member, and an annular side wall 14 formed on the mounting substrate 12. The light emitting element 20 has a structure as shown in FIG. 2, for example, and includes a light emitting layer 38 made of a semiconductor. Further, the two electrodes 42 and 46 of the light emitting element 20 are connected to the wirings 12a and 12b of the mounting substrate 12 through electrodes and wires formed on the wavelength conversion member 30, and can be energized from the outside. .

  The package 16 is formed with a recess 16a having an open upper surface so that the light emitting element 20 and the wavelength conversion member 30 can be accommodated. Moreover, in this Embodiment, the recessed part 16a is mortar shape so that light emission of the light emitting element 20 and the wavelength conversion member 30 can be taken out efficiently. That is, the recess 16a is formed by the inner surface of the side wall 14 of the package 16 and the upper surface of the mounting substrate 12, but the side wall 14 of the package 16 has an annular shape, and its inner diameter increases as it goes upward. As a result, the concave portion 16a has a mortar shape, and light incident on the surface of the concave portion 16a can be efficiently extracted from above. The concave portion 16a is filled with a translucent sealing member 28. As shown in FIG. 6, the recess 16a of the package 16 in FIG. 1 is circular in plan view, and has a structure in which a rectangular light emitting element 20 and a rectangular wavelength conversion member 30 are arranged near the center thereof. . The light emitting element 20 and the wavelength conversion members 24 and 26 are both installed in parallel to the bottom surface of the recess 16a.

  In the present embodiment, the wavelength conversion member 30 includes a first wavelength conversion member 24 that is a plate-like member in which an inorganic binder made of an inorganic material and a phosphor are combined, and the phosphor is dispersed in a translucent resin. And a second wavelength conversion member 26 formed as described above. On the bottom surface of the package 16, the first wavelength conversion member 24, the light emitting element 20, and the second wavelength conversion member 26 are sequentially directed toward the opening of the concave portion 16 a via the translucent support member 32. , Formed so as to be separated from the side surface of the recess 16a. The first wavelength conversion member 24 is disposed below the light emitting element 20 so as to support the light emitting element 20, and the second wavelength conversion member 26 is formed so as to cover the upper surface and the side surface of the light emitting element 20. The light emitted from the upper and side surfaces of the light emitting element 20 is partly wavelength-converted mainly by the second wavelength conversion member 26, and the light emitted from the lower surface of the light emitting element 20 is mainly converted by the first wavelength conversion member 24. The part is wavelength-converted. Light of a desired color can be obtained by mixing the light thus converted in wavelength and the light of the original light emitting element 20. For example, if the light emitting element 20 emits blue light and the wavelength conversion member 30 emits yellow light, white light emission can be obtained by mixing them. When a light emitting element that emits ultraviolet light is used as the light emitting element 20, light having a desired color can be obtained by the light that has been converted through the wavelength conversion member 30.

  According to the light emitting device 10 of the present embodiment, the first wavelength conversion member 24, the light emitting element 20, and the second wavelength conversion member are provided on the bottom surface of the package 16 via the translucent support member 32. 26 are sequentially formed, so that light can be efficiently extracted from below the light emitting element 20 through the first wavelength conversion member 24 and the support member 32. In addition, since the wavelength conversion members 24 and 26 are provided on both the upper and lower sides of the light emitting element 20, relatively uniform wavelength conversion is possible, while the first wavelength conversion member 24 positioned below the light emitting element 20 is provided. Since a plate-like member in which an inorganic binder made of an inorganic material such as glass or sapphire is combined with a phosphor, return light due to scattering of the wavelength conversion member 24 can be suppressed. That is, since the refractive index difference between the inorganic binder and the phosphor in the first wavelength conversion member 24 is relatively small, the light passing through the first wavelength conversion member 24 is not scattered so much, and the light is not converted into the first wavelength conversion member. There is little return light to the light emitting element 20 when passing through the member 24.

However, the first wavelength conversion member 24 formed on the lower side of the light emitting element 20 is less likely to be internally scattered, so that the first wavelength conversion member 24 is likely to be guided. There is a tendency to emit light strongly on the side. This can cause new color unevenness. Therefore, in the present embodiment, the scattering surface 18 is formed on the side surface of the recess 16a. For example, light-transmitting particles 17 such as TiO ₂ can be dispersed in a light-transmitting base material constituting the side wall 14 of the package 16, and the side surface of the recess 16 a can be used as the scattering surface 18. When light enters the side surface of the recess 16a of the package, it is scattered by the particles 17. As a result, as shown in FIG. 4, out of the light emitted from the light emitting element 20 and the wavelength conversion member 30, the light hitting the side surface of the recess 16a of the package is scattered there and then extracted to the outside. Thus, the light of the light emitting element 20 and the light of the wavelength conversion member 30 are mixed to suppress uneven color.

  In the present embodiment, since the light emitting layer 38 of the light emitting element 20 is separated from the side surface of the recess 16a of the package, the ratio of the light returning to the light emitting element 20 after being scattered by the scattering surface 18 of the recess 16a. There are few. In particular, if the inner diameter of the concave portion 16a is gradually increased toward the upper side, the light scattered on the side surface of the concave portion 16a becomes easier to move upward on average, and the rate of returning to the light emitting element 20 is further reduced. Therefore, even if a sufficient amount of particles 17 are dispersed on the side wall 14 of the package 16 to suppress color unevenness, the light emission output hardly decreases.

  The scattering surface 18 is preferably formed in the widest possible region of the side surface of the recess 16a. However, at least the side surface of the recess 16a from the side surface of the first wavelength conversion member 24 to the main surface of the first wavelength conversion member 24. It forms in the area | region where the light radiate | emitted with respect to parallel is irradiated. As a result, the light emitted from the side surface of the first wavelength conversion member 24 can be effectively scattered to suppress uneven color. Preferably, the scattering surface 18 includes a region irradiated with light emitted in parallel to the main surface of the first wavelength conversion member 24 from the side surface of the first wavelength conversion member 24, and all regions below the region are irradiated. Form. More preferably, the scattering surface 18 is formed in all regions below the position where the light emitted from the light emitting layer 38 of the light emitting element 20 in parallel with the main surface of the light emitting element 20 hits. Most preferably, the scattering surface 18 is formed on the entire side surface of the recess 16a. Thereby, uneven color can be effectively suppressed.

  In the present embodiment, the side surface of the recess 16a is a scattering surface, but a scattering surface can also be provided on the bottom surface of the recess 16a. For example, an appropriate scattering layer may be formed so as to leave a wire connection region on the surface of the mounting substrate 12. In the present embodiment, the light emitted from the semiconductor element 20 is scattered as it is on the scattering surface 18 so as not to be accompanied by optical effects other than scattering (for example, absorption or wavelength conversion). As a result, the loss of light generated on the scattering surface 18 can be suppressed, and the light extraction efficiency can be increased. In addition, it is preferable that most of the light emitted from the light emitting element 20 and the wavelength conversion member 30 and reflected and extracted by the bottom surface and side surface of the recess 16a is scattered by the scattering surface, but the light reflected by the bottom surface and side surface. May be taken out from the opening of the recess 16a without hitting the scattering surface. Further, many of the light emitted from the light emitting element 20 and the wavelength conversion member 30 are emitted from the opening of the recess 16a while being repeatedly reflected on the bottom surface and the side surface. Therefore, the light emitted from the light emitting element 20 and the wavelength conversion member 30 does not need to strike the scattering surface 18 from the beginning, and after being reflected by the bottom surface and the side surface of the concave portion 16a, before being extracted from the opening of the concave portion 16a. If it hits, the effect of suppressing color unevenness is exhibited.

Hereinafter, a preferable configuration and arrangement of each member of the light emitting device 10 according to the present embodiment will be described in detail.
(Wavelength conversion member 30)
In the present embodiment, the wavelength conversion member 30 includes the first wavelength conversion member 24 and the second wavelength conversion member 26, but the phosphors used for both may be the same or different. The phosphor used for the first wavelength conversion member 24 and the second wavelength conversion member 26 is preferably a phosphor excited by near ultraviolet light or visible light. In particular, when the light emitting element 20 is a blue light emitting element and it is desired to form a white light emitting device, it is preferable to use a phosphor that is excited by blue and exhibits yellow broad light emission. Examples of such a phosphor include a phosphor having a garnet structure activated by cerium (particularly, a phosphor activated by cerium and containing aluminum and having a garnet structure). Since the phosphor activated with cerium emits light in yellow and broad, white having good color rendering properties can be realized in combination with blue light emission. In addition, a garnet structure, particularly a phosphor having a garnet structure containing aluminum, is resistant to heat, light, and moisture, and can maintain yellow light emission with high luminance for a long time. For example, as the wavelength conversion _{material, (Re 1-x Sm x} ) 3 (Al 1-y Ga y) 5 O 12: Ce (0 ≦ x <1,0 ≦ y ≦ 1, where, Re is, Y, Gd It is preferable to use a YAG-based phosphor (generally abbreviated as YAG) represented by at least one element selected from the group consisting of La, Lu, and Tb. In addition to the yellow phosphor, Lu ₃ Al ₅ O ₁₂ : Ce, BaMgAl ₁₀ O ₁₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, Mn, (Zn, Cd) Zn: Cu, (Sr, Ca) ₁₀ ( Color rendering properties can also be adjusted using phosphors such as PO ₄ ) ₆ Cl ₂ : Eu, Mn, (Sr, Ca) ₂ Si ₅ N ₈ : Eu, CaAlSiB _x N _{3 + x} : Eu, and CaAlSiN ₃ : Eu. .

  In particular, when the emission wavelength of the light emitting element 20 is a short wavelength, the wavelength conversion member 30 may include two or more types of phosphors. It is also possible to excite and emit the first type of phosphor by the primary light from the light emitting element 20, and to excite and emit another type of phosphor by the secondary light emitted from the phosphor. In addition, if two types of phosphors having different chromaticities are used, an area formed by connecting the two types of phosphors and the chromaticity points of the light emitting elements on the chromaticity diagram by adjusting the amount of the two types of phosphors. Light emission corresponding to any of the chromaticity points can be obtained.

As described below, the first wavelength conversion member 24 and the second wavelength conversion member 26 have different preferred configurations because of their different roles in the light emitting device 10.
(1) First wavelength conversion member 24
The first wavelength conversion member 24 formed below the light emitting element 20 in parallel with the light emitting element mainly converts the wavelength of light emitted from the lower surface of the light emitting element 20 and also serves as a substrate for fixing the light emitting element 20. In addition, it also serves as a heat dissipation path from the light emitting element 20 to the mounting substrate 12. Since the first wavelength conversion member 24 is disposed below the light emitting element 20, the wavelength of light emitted downward from the light emitting element 20 can be converted, which is advantageous for suppressing color unevenness. In the present embodiment, the light emitted from the side surface and the lower surface of the light emitting element 20 and the light emitted from the first wavelength conversion member 24 are scattered and mixed by the scattering surface 18 formed on the side surface of the recess 16a. To the outside.

  The first wavelength conversion member 24 is a composite material of an inorganic binder made of an inorganic material and a phosphor. As the inorganic binder, inorganic crystals such as sapphire, amorphous materials such as glass, and various inorganic materials such as ceramics can be used. In general, an inorganic material such as glass or sapphire has a small difference in refractive index from a phosphor made of an inorganic material. For example, the refractive index of a phosphor having a garnet structure including aluminum is about 1.7 to 1.8, whereas the refractive index of a general light-transmitting resin is about 1.5, whereas the refractive index of glass. The refractive index is about 1.6, and the refractive index of sapphire is about 1.7. For this reason, there is little scattering of the light by the fluorescent substance in the 1st wavelength conversion member 24, and the return light to the light emitting element 20 can be suppressed. In addition, since the inorganic material has higher hardness than organic materials such as resin and can be processed at a high temperature, the first wavelength conversion member 24 using the inorganic binder can easily form a wiring thereon. Yes, it is preferable as a substrate surface on which the light emitting element 20 is mounted.

  The structure of the first wavelength conversion member 24 is preferably a structure in which a phosphor and an inorganic binder are mixed almost uniformly. For example, if the structure of the first wavelength conversion member 24 is a sea-island structure in which one of the phosphor and the inorganic binder is dispersed in an island shape in the other, uniform wavelength conversion can be performed in the first wavelength conversion member 24. It can be performed and is preferable. In this case, a structure in which the island-shaped phosphor is dispersed in the inorganic binder or a structure in which the island-shaped inorganic binder is dispersed in the phosphor may be employed. For uniform wavelength conversion, the island diameter in the sea-island structure can be, for example, 1 μm to 50 μm.

  The inorganic binder may be any inorganic material as long as it is translucent, but the refractive index difference from the phosphor is smaller than 0.3, more preferably 0.2 or less, and even more preferably 0.1. The following is desirable. In addition, the difference in refractive index between the inorganic binder and the phosphor in the first wavelength conversion member 24 is preferably smaller than the difference in refractive index between the translucent resin and the phosphor in the second wavelength conversion member 26. Thereby, the scattering in the 1st wavelength conversion member 24 can be reduced, and the fall of light extraction efficiency can be suppressed.

  The inorganic binder has a thermal conductivity of the first wavelength conversion member 24 of 0.8 [W / mK] or more, more preferably 1.2 [W / mK] or more, and further preferably 35 [W / m]. mK] or more is desirable. By configuring the first wavelength conversion member 24 with such a material, the durability of the first wavelength conversion member 24 itself is enhanced, and at the same time, heat radiation from the light emitting element 20 toward the mounting substrate 12 is improved, and the reliability is improved. A highly light-emitting device 10 can be realized.

  Since the first wavelength conversion member 24 in the present embodiment has a plate shape, the light emitting element 20 can be stably fixed. Further, if the first wavelength conversion member 24 is plate-shaped, the first wavelength conversion member is processed as a large plate-shaped material when the light emitting device 10 is manufactured, and is cut into a desired size. As a result, the light emitting device 10 can be easily assembled. Further, the first wavelength conversion member 24 in the present embodiment also functions as a mounting surface on which the light emitting element 20 is flip-chip mounted. However, since the first wavelength conversion member 24 is plate-shaped, wiring can be easily formed. It becomes. For example, a wiring pattern can be collectively formed on the first wavelength conversion member 24 processed into a large plate shape, and the wiring pattern can be cut out and bonded onto the support member 32. By connecting the wiring pattern on the surface of the first wavelength conversion member 24 and the light emitting element 20 with a conductive member such as metal or resin, or an adhesive, the heat generation of the light emitting element 20 is transmitted through the wiring pattern to the first wavelength conversion member. You can escape to 24. When the light emitting element 20 is flip-chip mounted, the light emitting layer 38 that easily generates heat can be brought close to the first wavelength conversion member 24, and heat can be efficiently radiated.

  The top-view shape of the first wavelength conversion member 24 is preferably substantially square, similar to the light emitting element 20. The first wavelength conversion member 24 overlaps with the light emitting element 20 in a top view and is preferably larger than the light emitting element 20. Specifically, the length of one side of the first wavelength conversion member 24 can be about 1.5 to 3.5 times the length of one side of the light emitting element 20. For example, when the light emitting element 20 has a substantially square shape with a side of about 450 μm, the first wavelength conversion member 24 has a substantially square shape with a side of about 1 mm, and the light emitting element 20 has a substantially square shape with a side of about 1 mm. The first wavelength conversion member 24 has a substantially square shape with a side of about 1.5 mm. At this time, the distance from the side surface of the first wavelength conversion member 24 to the scattering surface can be about 0.5 to 1.5 mm. Moreover, the thickness of the 1st wavelength conversion member 24 can select the thickness from which desired chromaticity is obtained, for example, shall be 100 micrometers-300 micrometers. In addition, the top view shape of the 1st wavelength conversion member 24 can be not only a rectangle but various shapes, such as circular and an ellipse.

  Since the first wavelength conversion member 24 has less internal scattering, the ratio of wavelength conversion of light from the light emitting element 20 is likely to be lower than that of the second wavelength conversion member 26. Therefore, in order to perform sufficient wavelength conversion by the first wavelength conversion member 24, it is preferable to form the first wavelength conversion member 24 to be thick to some extent. For example, the first wavelength conversion member 24 is preferably thicker than the light emitting element 20. The first wavelength conversion member 24 is preferably thicker than the second wavelength conversion member 26. Here, the thickness of the first wavelength conversion member 24 and the second wavelength conversion member 26 is assumed to be a thickness on a straight line that passes through the center of the light emitting element 20 and is perpendicular to the main surface of the light emitting element 20. . For the same reason, the phosphor concentration in the first wavelength conversion member 24 is preferably higher than the phosphor concentration in the second wavelength conversion member 26. Here, the concentration of the phosphor in the first wavelength conversion member 24 and the second wavelength conversion member 26 is considered as the weight of the phosphor in a unit volume.

  In the present embodiment, the light emitting element 20 is directly fixed on the first wavelength conversion member 24. However, a translucent member is disposed on the upper surface of the plate-like first wavelength conversion member, A light-emitting element can be provided thereover. For example, a translucent member having good heat conduction, such as sapphire or glass, may be provided between the first wavelength conversion member 24 and the light emitting element 20. By providing a translucent member having a larger dimension in the planar direction than the first wavelength conversion member 24, light of the light emitting element can be efficiently extracted from the side surface of the translucent member. That is, by extracting the light of the light emitting element from the side surface of the translucent member and irradiating the scattering surface 18 without passing through the wavelength conversion member 30, absorption loss when passing through the wavelength conversion member 30 can be reduced. . Further, if the dimension of the translucent member in the planar direction is larger than that of the light emitting element 20, light can be emitted from above and below the translucent member at a portion where the translucent member projects from the light emitting element 20. On the other hand, since the light emitted from the translucent member is scattered by the scattering surface 18 formed on the side surface of the recess 16a, color unevenness is also suppressed. Further, in order for the first wavelength conversion member 24 to be “plate-shaped”, the entire shape may be a plate shape, and may have a recess or a hole for placing the light emitting element. . Further, a pattern for obtaining some optical effect may be formed on the surface.

(2) Second wavelength conversion member 26
Next, the second wavelength conversion member 26 formed on the upper surface of the light emitting element 20 mainly performs a wavelength conversion process on the light emitted from the light emitting element 20 and extracted outside without hitting the package recess 16a. Fulfill. Since such light is not mixed by the scattering surface 18, the second wavelength conversion member 26 has a structure in which a phosphor is dispersed in a translucent resin so that light is scattered inside. In addition, it is preferable to form the second wavelength conversion member 26 so that the optical path length through which the light emitted from the light emitting element 20 passes is substantially uniform. Thus, a light emitting device with little color unevenness can be obtained. Specifically, a phosphor made of an inorganic material such as a garnet phosphor is dispersed in a translucent resin having a refractive index difference of 0.3 or more, more preferably 0.4 or more. As the translucent resin, it is preferable to use a silicone resin composition, a modified silicone resin composition, etc., but an insulating resin having translucency such as an epoxy resin composition, a modified epoxy resin composition, an acrylic resin composition, etc. Can be used. In addition, resins having excellent weather resistance such as hybrid resins containing one or more of these resins can also be used. The second wavelength conversion member 26 preferably covers the upper surface and side surfaces of the light emitting element 20 with a substantially uniform thickness. The second wavelength conversion member 26 formed by dispersing a phosphor in a translucent resin can easily cover the upper surface and side surfaces of the light emitting element 20 with a substantially uniform thickness by using a technique such as potting.

  On the other hand, the second wavelength conversion member 26 is preferably formed so as not to cover the side surface of the first wavelength conversion member 24. Thereby, light can be efficiently extracted from the side surface of the first wavelength conversion member 24. For the same reason, the second wavelength conversion member 26 covers the first wavelength conversion member 24 in the vicinity of the light emitting element 20, while the first wavelength conversion member 26 covers the first wavelength. The vicinity of the outer periphery of the conversion member 24 is preferably not covered with the second wavelength conversion member.

  In addition, the upper surface of the second wavelength conversion member 26 is preferably a gentle curved surface. Thereby, total reflection of light in the second wavelength conversion member 26 can be suppressed, and light extraction efficiency can be increased. In order to make the upper surface of the second wavelength conversion member 26 a gentle curved surface, a technique such as potting can be used.

  A pattern for obtaining some optical effect, such as a lens pattern, may be formed on the light receiving surface and the light emitting surface of the first wavelength conversion member 24 and the second wavelength conversion member 26. As described above, the first wavelength conversion member 24 in the present embodiment is “plate-like”, but any pattern may be formed on the surface as long as the overall shape is plate-like. Further, even if a certain pattern is on the fixing surface of the light emitting element, the light emitting element can be stably fixed if the period of the pattern is sufficiently small with respect to the size of the light emitting element.

(Arrangement of light emitting element 20 and wavelength conversion member 30)
In the present embodiment, in order for the light emission of the light emitting element 20 and the light emission of the wavelength conversion member 30 to be favorably mixed by the scattering surface 18, the light emission of the light emitting element 20 and the wavelength conversion member 30 is a surface having a wide scattering surface 18 of the recess. It is advantageous to apply evenly. For that purpose, it is preferable that both the light emitting layer 38 and the wavelength conversion member 30 of the light emitting element 20 are separated from the side surface and the bottom surface of the recess 16a. Further, if both the light emitting layer 38 and the wavelength conversion member 30 are separated from the side surface and the bottom surface of the recess 16a, the ratio of the scattered or reflected light returning to the light emitting element 20 or the wavelength conversion member 30 is reduced, and the light extraction efficiency is also improved. improves.

  For example, in the present embodiment, as shown in FIG. 3, the maximum width in the planar direction of the light emitting layer 38 is w [μm], and the distance d from the light emitting layer 38 of the light emitting element 20 to the bottom surface of the recess 16a is at least 0. The light emitting layer 38 is disposed so as to be 5 w [μm] or more. Depending on the structure of the package 16, the bottom surface of the recess 16 a may have some laminated structure. In this case, the surface from which the light emission layer 38 reflects the light most strongly is used as a reference, and from there to the light emission layer 38. Let the distance be d. When the distance from the light emitting layer 38 to the surface of the recess 16a that reflects light is too close, such as when the light emitting element 20 is directly fixed to the bottom surface of the recess 16a, most of the light emitted from the light emitting layer 38 is directed to the light emitting element 20. Returning, the light is absorbed again by the semiconductor layer and the electrode in the light emitting element 20. Assuming light that exits from the end of the light emitting layer 38 and is reflected by the bottom surface of the recess 16a, if the distance d from the light emitting layer 38 to the bottom surface of the recess 16a is 0.5 w or more, the light is emitted downward from the end of the light emitting layer 38. If the incident angle α with respect to the bottom surface of the recess 16a (the angle formed by the normal to the bottom surface of the recess 16a and the light beam incident on the bottom surface) is 45 ° or more, the light can be extracted outside. Therefore, by setting the distance d from the light emitting layer 38 to the bottom surface of the recess 16 a to be 0.5 w or more, the light emitted downward from the light emitting layer 38 is easily emitted outside without returning to the light emitting element 20. The critical value of the incident angle α becomes smaller as the distance d from the light emitting layer to the bottom surface of the recess 16a becomes longer, and it becomes easier to extract the emitted light to the outside. The distance d from the light emitting layer 38 to the bottom surface of the recess 16a is preferably 1 w [μm] or more, more preferably 2 w [μm] or more. In addition, the light emitting layer 38 is desirably disposed above one third of the depth of the recess 16a (= distance from the bottom surface to the top surface of the recess). As described above, the light emitting layer 8 in the light emitting element 20 is disposed sufficiently apart from the bottom surface of the recess 16a, so that light emitted downward from the light emitting layer 38 is reflected by the bottom surface of the recess 16a and then again emitted from the light emitting element 20. The probability of returning to itself decreases, and the light emission of the light emitting element 20 can be used efficiently. Further, it is preferable that the distance d from the light emitting layer 38 to the bottom surface of the recess 16a is longer because light emitted downward from the light emitting layer 38 is irradiated to a wide range of scattering surfaces. Similarly, the distance from the wavelength conversion member 30 to the bottom surface of the recess 16a is desirably 0.5 w 'or more, preferably 1 w' or more, where the maximum width of the wavelength conversion member 30 is w '.

  In addition, the shortest distance from the end of the light emitting layer 38 to the side surface of the recess 16a includes the light emitting layer 38 of the light emitting element 20, and the maximum width in the planar direction of the light emitting layer 38 is considered. It is desirable to arrange the light emitting layer 38 so that w [μm] is 0.5 w [μm] or more, 1 w [μm] or more, more preferably 3 w [μm] or more. As a result, the light emitted from the light emitting layer 38 in the lateral direction strikes a wider scattering surface. Further, the rate at which the light scattered by the scattering surface of the recess 16a returns to the light emitting element 20 also decreases. Similarly, the shortest distance from the wavelength conversion member 30 to the side surface of the recess 16a where the scattering surface is formed is 0.5 w ′ or more, considering the wavelength conversion member 30 in a plane parallel to the wavelength conversion member 30. Preferably it is 1 w 'or more. In considering the above distance, the shortest distance from the end of the light emitting element 20 or the wavelength conversion member 30 to the side surface of the concave portion is considered. In addition, when there are a plurality of wavelength conversion members 30, the relationship between the distances is considered individually for each.

  Further, in order to satisfactorily mix the light emission of the light emitting element 20 and the light emission of the wavelength conversion member 30 by the scattering surface 18, the relative positional relationship among the light emitting element 20, the wavelength conversion member 30 and the scattering surface 18 is also considered. There is a need. In order to improve color mixing and suppress color unevenness, the distance between the wavelength conversion member 30 and the light emitting element 20 is preferably smaller than the distance between the wavelength conversion member 30 and the scattering surface 18. If the wavelength conversion member 30 is separated from the light emitting element 20 and is too close to the scattering surface 18, the light of the light emitting element 20 that reaches the scattering surface without passing through the wavelength conversion member 30 increases and light emitted from the wavelength conversion member 30. This is because it is difficult to uniformly irradiate the scattering surface 18. It is preferable that at least the main wavelength conversion member satisfies the above relationship. Further, since the color unevenness of the light emitted from the side of the light emitting element 20 and the wavelength conversion member 30 is strong, the separation distance between the light emitting element 20 and the wavelength conversion member 30 and the side scattering surface 18 is the bottom surface of the recess 16a. It is desirable to arrange it so that it is larger than the separation distance from each other.

  In the light emitting device 10 of the present embodiment, among the light emitted from the light emitting element 20 and the wavelength conversion member 30, light that does not hit the side surface of the recess 16a of the package cannot be mixed by scattering. The light emitted from the upper surface of the light emitting element 20 in the direction perpendicular to the upper surface of the recess 16a is directly taken out without hitting the side wall of the recess 16a. For example, as shown in FIG. 4, when the upper surface of the light emitting element 20 is mounted parallel to the upper surface of the recess 16a, the light emitted from the upper surface of the light emitting element 20 in the normal direction is the scattering surface 18 of the recess 16a. It is taken out directly without hitting. Therefore, in the present embodiment, the second wavelength conversion member 26 is formed on the upper surface side of the light emitting element 20, and the light emitted from the upper surface of the light emitting element 20 and extracted outside without hitting the surface of the recess 16a is first. The second wavelength conversion member 26 is passed through. As a result, the light that has passed through the second wavelength conversion member 26 and the light that has been scattered on the scattering surface 18 are taken out from the opening on the upper surface of the recess 16a and emitted from the light emitting device. Since the second wavelength conversion member 26 can be formed so as to cover the light emitting element 20 after it is mounted, it is relatively easy to form the second wavelength converting member 26 along the light emitting element 20. In the case where the second wavelength conversion member 26 that covers the upper surface of the light emitting element 20 is not provided, the light emitted from the light emitting element 20 that does not directly hit the surface of the concave part 16a is reflected by the concave part 16a with an appropriate reflector or the like. You may return to.

Also, it is difficult to make the optical path length completely uniform for the light emitted from the light emitting element 20 and passing through the second wavelength conversion member 26. In particular, uneven color tends to occur with respect to light that passes through the second wavelength conversion member 26 obliquely. Therefore, the light emitted from the light emitting element 20 is not directly taken out to the outside, but is preferably scattered by the scattering surface 18 as much as possible to suppress color unevenness. Of the light emitted from the light emitting element 20 and the wavelength conversion member 30, the ratio of the light extracted directly without being reflected by the recess 16a of the package varies depending on the position of the light emitting layer 38 in the recess 16a. When the light emitting layer 38 is arranged away from the upper surface of the recess 16a, the ratio of light extracted outside without hitting the side surface of the recess 16a is reduced, and the effect of color mixing by the scattering surface 18 is enhanced. Further, when the light emitted from the light emitting element 20 in the lateral direction is scattered by the scattering surface 18 and then taken out through the opening on the upper surface of the recess 16a, the scattered light is more when the light emitting element 20 is farther from the upper surface of the recess 16a. Is preferably taken out after sufficiently spreading. The maximum width in the planar direction of the light emitting layer 38 is w [μm], and the distance d ₂ from the light emitting layer 38 of the light emitting element 20 to the upper surface of the recess 16a is at least 0.5 w [μm], more preferably 1 w [μm]. It is desirable to arrange the light emitting layer 38 so as to achieve the above. Further, in order to scatter most of the light from the light emitting layer 38 in the scattering surface 18, the distance d ₂ the distance d and either the same extent, it is preferably larger than that. Here, the “upper surface” of the recess 16a refers to a plane including the upper end of the recess 16a. In addition, when the recess 16a is filled with the sealing member and the surface of the sealing member is disposed on the light emitting element 20 side from the plane including the upper end of the recess 16a, light is reflected at the interface between the sealing member and the air. Therefore, it is desirable to determine the position of each member with the surface of the sealing member as the “upper surface” of the recess 16a. In particular, when the surface of the sealing member is a substantially flat surface, it is desirable to handle in this way. The interpretation of this “upper surface” is the same in other embodiments.

Further, as shown in FIG. 3, an angle formed by a line connecting the center of the light emitting layer 38 and the upper end of the recess 16a and the optical axis of the recess 16a (= the optical axis direction when the recess is a reflecting mirror having no scattering function). , Β of the light emitted from the center of the light emitting layer 38 to the upper surface is not reflected by the concave portion 16a of the package and is not reflected by the concave portion 16a of the package. Reach the top surface. Therefore, it is preferable to determine the relationship between the concave portion 16a and the light emitting layer 38 so that the angle β is small because the scattering effect on the surface of the concave portion 16a is increased. It is desirable that the angle β is 90 ° or less, more preferably 70 ° or less. On the other hand, if the angle β is too small, the light emitting device has a strong light emission directivity, which is not preferable depending on the application. On the other hand, if the angle β is too small, light emission of the light emitting element 20 is likely to return to the light emitting element 20 due to repeated scattering on the surface of the recess 16a, and the output of the light emitting device 10 is reduced. Therefore, the angle β is desirably 30 ° or more, more preferably 50 ° or more. Angle β can be adjusted by the distance _{d 2.} about d ₂ is longer, β decreases. Further, the angle β can also be adjusted by increasing or decreasing the width of the opening of the recess 16a that is the emission part. If the width of the opening is narrowed, β becomes smaller.

In the case where the sealing member is filled in the recess 16a, the light that has reached the upper surface of the recess 16a is, light incident on the upper surface of the total reflection critical angle theta _c following angles recess 16a is directly outside retrieved, light rays incident at an angle greater than the critical angle theta _c is returned to the recess 16a by total internal reflection. Therefore, when the critical angle θ _c is smaller than the angle β, the light extracted directly can be reduced, and the light returned into the recess 16a by the total reflection can be scattered by the scattering surface, so that the color unevenness is further increased. Can improve. The sealing member can promote total reflection on the surface of the sealing member by making the upper surface substantially flat. On the other hand, when the critical angle theta _c is larger than the angle β is the ratio of light to be extracted directly increases, the it is preferred in terms of light extraction efficiency. In addition, since the sealing member has a shape protruding from the recess 16a so that the upper surface thereof is a convex curved surface, surface reflection of the sealing member can be reduced and light extraction efficiency can be improved.

(Supporting member 32)
In the present embodiment, the light-emitting element 20 is mounted on the mounting substrate 12 via the first wavelength conversion member 24 and the support member 32 so that the light-emitting layer 38 of the light-emitting element 20 is separated from the bottom surface of the recess 16a of the package by a predetermined distance. It is fixed to. The support member 32 in the present embodiment is translucent to the light emission of the light emitting layer 38 so that the light emitted downward from the light emitting layer 38 can be used efficiently. Further, since the support member 32 forms a heat radiation path from the light emitting element 20 to the mounting substrate 12 together with the first wavelength conversion member 24, the support member 32 is preferably made of a material having high thermal conductivity. It is desirable to use a material having a thermal conductivity of 0.8 [W / mK] or more, more preferably 1.2 [W / mK] or more, and still more preferably 35 [W / mK] or more. As the support member 32, for example, an inorganic material such as sapphire or glass can be used. Among these, sapphire is preferable because it has a relatively high thermal conductivity and exhibits high transmittance with respect to the blue light emitted from the light emitting element 20. Moreover, it is preferable that the support member 32 does not contain the particle | grains which scatter light including a fluorescent substance. At least the scattering inside the support member 32 needs to be weaker than the scattering inside the first and second wavelength conversion members 24 and 26. In addition, a translucent substrate is preferably used as the support member 32 in order to dispose the first wavelength conversion member 24 on the support member 32 and separate it from the bottom surface of the recess 16a.

  Since the members interposed between the light emitting element 20 and the mounting substrate 12 including the support member 32 serve as a heat dissipation path from the light emitting element 20 toward the mounting substrate 12, it is preferable to use a material having high thermal conductivity. For example, in the present embodiment, it is preferable that both the first wavelength conversion member 24 and the support member 32 be made of a material having high thermal conductivity. The main material of the support member 32 has a thermal conductivity of 0.8 [W / mK] or more, more preferably 1.2 [W / mK] or more, and further preferably 35 [W / mK] or more. desirable. As a result, the heat dissipation efficiency of the light emitting element 20 is increased, and thus the light emitting device 10 can be obtained in which the light emission output is hardly reduced even when the light emitting element 20 is lit for a long time. It should be noted that a member having low thermal conductivity may be present between the light emitting element 20 and the bottom surface of the recess 16a in a thin film that does not significantly hinder the overall thermal conduction. For example, even if the first wavelength conversion member 24 and the support member 32 having a high thermal conductivity are joined by an adhesive layer having a low thermal conductivity, the overall thermal conductivity may be within the above range. . Considering heat sinking, as shown in FIG. 1, the support member 32 is desirably provided so as to be in contact with at least one of the wirings 12a and 12b. Further, a radiator such as a metal member insulated from the wiring may be provided, and the support member 32 may be provided on the radiator. The support member 32 and the wirings 12a and 12b are bonded with resin, metal paste, or the like. It is desirable to use a metal paste having a high thermal conductivity. In this case, adhesion can be improved by providing a metal film on the surface of the support member 32 and bonding the metal film side with a metal paste. The metal film can also be used as a reflective layer.

  Moreover, it is preferable that the member interposed between the light emitting element 20 and the recessed part 16a including the support member 32 has translucency so that the light emission of the light emitting element 20 may not be absorbed. It should be noted that a member with low translucency may exist between the light emitting element 20 and the bottom surface of the recess 16a in a thin film that does not hinder the entire translucency. For example, even if the translucent first wavelength conversion member 24 and the translucent support member 32 are joined with an adhesive layer having low translucency, the translucency of the entire member that supports the light emitting element 20 is achieved. If it is not hindered. When such a low translucency member is interposed between the light emitting element 20 and the bottom surface of the recess 16a, the first ratio is set so that the ratio of blocking light from the light emitting layer 38 toward the bottom surface of the recess 16a is reduced. It is desirable to provide a width narrower than that of the wavelength conversion member 24, more preferably a width narrower than that of the light emitting layer 38. When a light reflecting member having a larger area than the light emitting element 20 is present between the light emitting element 20 and the bottom surface of the recess 16a, the light reflecting layer 38 and the first light emitting member 38 are used with the light reflecting member as the bottom surface of the substantial recess. It is desirable to adjust the arrangement of the wavelength conversion member 24.

  In addition, it is preferable to laminate | stack in order of the support member 32 and the 1st wavelength conversion member 24 from the bottom face of the recessed part 16a, and, thereby, the 1st wavelength conversion member 24 can be spaced apart from the bottom face of the recessed part 16a. When the first wavelength conversion member 24 is separated from the bottom surface and the side surface of the concave portion 16a, the light emitted from the first wavelength conversion member 24 is likely to be widely irradiated on the scattering surface. Further, the rate at which the light scattered or reflected by the recess 16a returns to the first wavelength conversion member 24 also decreases. Further, although the support member 32 is a light-transmitting member, a part of light is trapped without being extracted due to total reflection at the interface between the support member 32 and the surrounding members. It is desirable to arrange the support member 32 so that the light traveling downward from the first wavelength conversion member 24 can directly reach the scattering surface 18 to the extent that the first wavelength conversion member 24 can be supported. Preferably, the width of the support member 32 is equal to or less than the width of the first wavelength conversion member 24 and is preferably half or more of the width of the first wavelength conversion member 24.

(Light emitting element 20)
The light emitting element 20 only needs to have a light emitting layer made of a semiconductor. In particular, a light emitting device including a light emitting layer made of a nitride semiconductor, particularly a light emitting layer made of a gallium nitride compound semiconductor (particularly InGaN), can emit strong light in the short wavelength region of the visible light region or the near ultraviolet region. Therefore, it can be suitably combined with the wavelength conversion member. In the light emitting element 20, the emission peak wavelength of the emitted light output from the light emitting layer 38 is 240 nm, which is a short wavelength region from near ultraviolet to visible light.
It is desirable to have an emission spectrum in the vicinity of ˜500 nm, preferably 380 nm to 420 nm, more preferably 450 nm to 470 nm. If it is a light emitting element which emits light in this wavelength range, it becomes possible to emit a desired color, particularly white light, in combination with various wavelength conversion members. The light emitting element 20 may have a light emitting layer made of a semiconductor such as ZnSe, InGaAs, or AlInGaP.

  FIG. 2 is a schematic cross-sectional view illustrating an example of the light emitting element 20. A light-transmitting insulating substrate 34 such as sapphire is provided on a first conductivity type (for example, n-type) semiconductor layer 36, a light emitting layer 38, and a second conductivity type (for example, a conductivity type different from the first conductivity type). , P-type) semiconductor layers 40 are sequentially stacked. The second conductive type semiconductor layer 40 and the light emitting layer 38 are partially removed to expose the first conductive type semiconductor layer 36, and a first electrode (n-side electrode) 42 is formed on the exposed surface. . The second conductivity type semiconductor layer 40 has a second electrode (p-side ohmic electrode) 44 formed on substantially the entire surface, and a pad electrode (p-side pad electrode) 46 for connection to the outside. Yes. Each electrode can be a translucent or reflective electrode. Usually, a translucent electrode is used when the electrode forming surface is mounted on the upper side, and the electrode forming surface is formed as shown in FIG. In the case of the light emitting element 20 that is flip-chip mounted as the lower side, a reflective electrode is used.

  As shown in FIG. 1, in this embodiment, the substrate 34 of the light emitting element 20 is flip-chip mounted on the first wavelength conversion member 24 with the substrate 34 facing upward. A mounting electrode is formed on the upper surface of the first wavelength conversion member 24 and is connected to the first electrode 42 and the second electrode 46 of the light emitting element 20 via solder bumps or the like. The electrodes formed on the upper surface of the first wavelength conversion member 24 are further connected to the wirings 12a and 12b of the mounting substrate 12 by wires. As a result, the light emitting element 20 can be electrically driven from the outside. For the electrode formed on the upper surface of the first wavelength conversion member 24, a member that substantially shields light from the light emitting layer 38 is usually used. For this reason, the electrode on the upper surface of the first wavelength conversion member 24 is formed only on a part of the upper surface of the first wavelength conversion member 24 so that light traveling downward from the light emitting element 20 can reach the bottom surface of the recess 16a. . Preferably, the electrode portion protruding from the light emitting element 20 in a top view is formed with a width smaller than the width of the light emitting element 20.

  The light emitting element 20 that can be used in the present invention is not limited to the structure shown in FIG. For example, each conductive type layer may be provided with an insulating, semi-insulating, and reverse conductive type structure in part. Further, the substrate 34 may be conductive, and in this case, the first electrode 42 may be formed on the back surface of the substrate 34. The substrate 34 may be a substrate used for growing a semiconductor layer, or may be a substrate bonded after the semiconductor layer is grown. Alternatively, the substrate can be peeled off and only the semiconductor layer can be used as a light-emitting element. The shape of the light emitting element 20 in a top view is typically a rectangle, and preferably a substantially square shape. By making it substantially square, the distance from each side of the light emitting element 20 to the scattering surface can be made substantially equal, and color unevenness can be easily suppressed. The top view shape of the wavelength conversion member 24 is preferably substantially the same as that of the light emitting element 20. As the light emitting element 20, one having a side of about several hundred μm to several mm can be used, and specifically, a substantially square element having a side of about 400 μm to 1 mm can be used. At this time, the distance from the side surface of the light emitting element 20 to the scattering surface 18 is, for example, about 0.5 to 2 mm.

(Package 16, recess 16a)
If the package 16 has a concave portion 16a having a part of the surface as a scattering surface and can accommodate the light emitting element 20 and the wavelength conversion member 30 so that electrical connection to the light emitting element 20 is possible, Any structure is acceptable. In the present embodiment, the package 16 includes a mounting substrate 12 in which wirings 12a and 12b are formed on a flat insulating member, and an annular side wall 14 formed on the mounting substrate 12, and the package 16 in a top view. The outer shape of this is a rectangle and is cut into a circle to form an annular side wall 14. A recess 16 a is configured by the upper surface of the mounting substrate 12 and the inner surface of the side wall 14. In the present embodiment, the side surfaces of the recesses 16 a are used as the scattering surfaces 18 by dispersing translucent particles 17 having a refractive index different from that of the base material in the translucent base material constituting the side wall 14.

  The concave portion 16a may have any shape as long as the light emitting element 20 and the wavelength conversion member 30 can be accommodated and the upper surface is opened so that light can be extracted. However, the bottom surface of the recess 16a is preferably flat so that the light emitting element 20 and the like can be stably fixed. Moreover, it is preferable that the internal diameter of the recessed part 16a becomes large gradually from the bottom face toward the upper surface. Further, the recess 16a preferably has a circular shape in plan view, thereby improving the uniformity of light emission and suppressing color unevenness. An example is shown in FIGS. 5 and 6 are a schematic perspective view and a top view showing an example of the light-emitting device in this embodiment. In particular, when the planar view shape of the light source including the light emitting element 20 and the wavelength conversion member 30 is rectangular, there is a difference in intensity between the light emitted from the sides of the rectangle and the light emitted from around the corners. However, the unevenness of color due to the shape of the light source can be suppressed by scattering the light thus extracted in the circular recess 16a. Furthermore, it is preferable that the concave portion 16a has a mortar shape that is circular in plan view when viewed at any height. Further, the recess 16a may be a rectangle having a shape similar to that of the light emitting element 20 in plan view. The light source including the light emitting element 20 and the wavelength conversion member 30 is preferably disposed at the center of the recess 16a in plan view. In addition, as shown in FIG. 6, it is preferable that the scattering surface 18 formed on the side surface of the recess 16 a is disposed outside the light emitting element 20 and the wavelength conversion member 30 and can be observed when viewed from above. In particular, the light emitting element 20 and the wavelength conversion member 30 are preferably formed in the bottom surface of the recess 16a in a top view.

  The scattering surface 18 formed on the surface of the recess 16a is a surface capable of scattering the light emission of the light emitting element 20 and the light emission of the wavelength conversion member 30. In order to obtain a surface that can be scattered, a fine structure made of a material having a refractive index different from that of the surroundings is equal to or smaller than the shorter wavelength of the light emitted from the light emitting element 20 and the light emitted from the wavelength conversion member 30. A distributed surface may be used.

For example, as in the side wall 14 of the present embodiment, the scattering surface 18 can be formed by dispersing translucent particles having a refractive index different from that of the base material in the translucent base material. The refractive index difference between the particles and the surrounding material is preferably 0.1 or more, more preferably 1.0 or more. The particles include glass fibers, glass beads, talc, silica, alumina, magnesia, zinc white, calcium carbonate, barium sulfate, titania, aluminum hydroxide, mica, feldspar powder, quartz powder and other inorganic particles, silicone resin Organic particles such as fluorine resin, epoxy resin, and styrene-based crosslinked resin can be used, and one of these can be used alone or in combination of two or more. The particles 17 are particularly preferably oxides containing any of Ti, Zr, Nb, Al, Si, AlN, MgF, etc. (as oxides containing Ti, Zr, Nb, Al, Si, TiO ₂ , preferably _{ZrO 2, Nb 2 O 5,} Al 2 O 3). Among these, an oxide containing any of Ti, Zr, Nb, and Al, particularly TiO ₂ is preferable. The particles 17 made of these materials are preferable because they have a large refractive index and a large refractive index with the base material, so that the scattering becomes strong. Any oxide is preferable because it does not absorb in the visible light region and does not contribute to a reduction in efficiency.

  The average particle size R of the particles preferably satisfies 0.4 × λ / π <R <λ, where λ is the emission wavelength of the light emitting element 20 so that scattering occurs efficiently. When the average particle diameter R of the particles becomes 0.4 × λ / π or less, the particle enters the Rayleigh scattering region, and the scattering intensity is proportional to the fourth power of the wavelength. Therefore, the scattering of the light emission of the phosphor having a long wavelength is weakened. The average particle diameter R of the particles is 70 nm or more, preferably 200 nm or more, and is 400 nm or less, preferably 300 nm or less.

  On the other hand, the surrounding base material containing the particles 17 is preferably a silicone resin, an epoxy resin, glass or the like. Among them, silicone resins have thermosetting properties, light resistance, and relatively soft properties. Silicone resin has a low refractive index of about 1.4, so that it is easy to make a refractive index difference between particles such as TiO 2 (refractive index of about 2.5), and is preferable for enhancing scattering by the scattering surface 18.

The particles 17 are preferably contained to such an extent that they are observed as white. This makes it possible to form the scattering surface 18 with low translucency and high reflectance, and to improve the light extraction efficiency from the opening of the recess 16a. Moreover, the scattering coefficient of a scattering surface can be adjusted with the quantity which contains particle | grains. For example, the amount of the particles can be 10 to 50% by weight, and particularly when the particles of TiO ₂ are contained, the amount is preferably 20 to 40% by weight. If the content of the particles is 30% by weight or more, it is preferable because the scattering on the scattering surface 18 becomes strong and the reflectance becomes high.

  In addition, you may form the scattering surface 18 formed in the surface of the recessed part 16a with another method. For example, if the side wall 14 is formed using a porous body formed by agglomerating and sintering particles, the inner surface thereof can be used as a scattering surface. Moreover, it is good also as the side wall 14 using the porous body shape | molded by the sol gel method. In such a porous body, scattering occurs based on a difference in refractive index between the material of the porous body and air (or a substance having a different refractive index filled therein) existing in the pores of the porous body. In addition, when such a porous body is used for the side wall 14, in order to improve sealing performance and airtightness, it is good also as a composite material of a porous body and resin. Moreover, it can also be set as a scattering surface by giving uneven | corrugated processing or roughening to the surface of a translucent member or a reflective member, or forming a scattering particle layer in the surface.

  Further, by forming the scattering surface 18 also on the bottom surface of the recess 16a, light can be widely scattered and extracted from the opening of the recess 16a. On the other hand, the bottom surface of the recess 16a may be a surface that is smaller in scattering than the scattering surface 18, and in this case, it is preferable to arrange a light reflective member on the bottom surface of the recess 16a. Accordingly, the light that has reached the bottom surface of the recess 16a from the light source part can be reflected and extracted, and if a part of the reflected light reaches the scattering surface 18 on the side surface of the recess 16a, Light emitted downward can also be scattered by the scattering surface 18 and extracted.

In addition, when providing the scattering surface 18 in the side surface of the recessed part 16a, it is preferable to form the scattering surface 18 so that the circumference | surroundings of the light emitting element 20 may be enclosed equally. That is, it is preferable that the scattering surface 18 is formed uniformly in all directions with the center of the light emitting element 20 as a reference in plan view. This is because, when the scattering surface 18 is formed widely only in a certain direction with respect to the center of the light emitting element 20, or when the scattering surface 18 is not formed only in a certain direction, color unevenness is caused. Also, reducing the angle β described above, specifically, or be greater than the distance d the distance d ₂ described above, by reducing the width of the opening of the recess 16a, the light emitting element 20 and the wavelength conversion The ratio of the scattering region to the total luminous flux of the light source including the member 30 can be increased. Further, since the ratio of the scattering region can be increased by increasing the distance between the light source and the scattering surface 18, it is preferable that the distance between the light source and the scattering surface 18 is equal to or longer than the distance d. In the case where the bottom surface of the recess 16a is not a scattering surface, it is preferable to make the bottom surface small, and in plan view, the maximum width of the bottom surface is preferably about 1 to 1.2 times the maximum width of the light source. In order to efficiently extract the light irradiated on the scattering surface, as shown in FIG. 6, the scattering surface 18 formed on the side surface of the recess 16a is located outside the light emitting element 20 and the wavelength conversion member 30 as viewed from above. It is desirable to be able to be observed by being arranged in the area.

  The “bottom surface” of the concave portion 16a refers to a region of the concave portion 16a that includes the projection surface of the light emitting element 20 in the optical axis direction of the concave portion 16a and is not more than the same height as the projection surface. "" Refers to the region rising from the "bottom surface". The interpretation of the “bottom surface” and the “side surface” is the same for the recess 16a in the other embodiments.

(Mounting board 12)
The mounting substrate 12 only needs to have a wiring on the surface that is electrically connected to the light emitting element 20. In the present embodiment, wiring is formed on a flat insulating member to form the mounting substrate 12. As the insulating member, ceramic such as aluminum nitride or alumina, or glass can be used. Further, an insulating thin film layer such as aluminum nitride may be formed on the surface of a semimetal such as Si or metal. These mounting boards 12 are preferable because of their high heat dissipation. The wiring can be formed by patterning the metal layer by an ion milling method or an etching method. For example, a wiring pattern made of a platinum thin film or the like can be formed on the surface of aluminum nitride. Furthermore, a protective film made of a thin film such as SiO ₂ may be formed for the purpose of protecting the wiring pattern. Further, a heat radiator such as a metal member insulated from the wiring of the mounting board can be provided in the region where the support member is provided.

(Sealing member 28)
The material of the sealing member 28 filled in the recess 16a is not particularly limited as long as it is translucent. Although it is preferable in terms of durability to use a silicone resin composition, a modified silicone resin composition, etc., an insulating resin composition having translucency such as an epoxy resin composition, a modified epoxy resin composition, an acrylic resin composition, etc. Can also be used. Moreover, sealing members excellent in weather resistance, such as hybrid resins containing at least one of these resins, can also be used. Furthermore, inorganic materials having excellent light resistance such as glass and silica gel can be used. The sealing member is a member having a light transmittance from the light emitting element 20 and the wavelength conversion member 30 higher than that of the wavelength conversion member 30, and the phosphor content is preferably smaller than that of the wavelength conversion member 30, and more preferably fluorescent. It is set as the translucent member which does not contain a body. Moreover, it is preferable not to contain the scattering agent which scatters light. The upper surface of the sealing member 28 is preferably substantially flat and substantially parallel to the first wavelength conversion member 24. Accordingly, light emitted obliquely from the main surface of the plate-shaped first wavelength conversion member 24 or light emitted from the side surface is easily incident on the sealing member 28 at a high angle, and is thus returned to the recess 16a and scattered. It becomes easy to let. Further, a lens effect can be provided by making the light emitting surface side of the sealing member 28 have a desired shape. The size of the lens can be selected to be smaller or larger than the upper surface of the recess 16a, and the light distribution can be controlled by providing a groove on the surface of the lens.

Embodiment 2
FIG. 7 is a schematic cross-sectional view showing the light emitting device according to the second embodiment. In the present embodiment, the light emitting element 20 is mounted face up on the upper surface of the first wavelength converting material, and the second wavelength converting material is provided around the light emitting element. Other points are the same as in the first embodiment. The wavelength converting substance can be formed, for example, by printing a resin containing a phosphor.

  The light emitting element 20 has the structure shown in FIG. 2, for example, and is fixed on the first wavelength conversion member 24 with the substrate 34 facing down. The light-emitting element 20 preferably has a light-transmitting substrate 34 such as sapphire so that light emission in the downward direction of the light-emitting layer 38 can be used effectively. In order to fix the light emitting element 20 to the upper surface of the first wavelength conversion member 24, it is preferable to use a translucent adhesive. For example, silicone or the like can be used. The first electrode 42 and the second electrode 46 formed on the upper surface of the light emitting element 20 are connected to the wirings 12a and 12b of the mounting substrate by wires, respectively.

  As described above, by mounting the light emitting element 20 face up, light re-incident on the light emitting element 20 can be suppressed. In addition, the first wavelength conversion member 24 does not require wiring and can be easily manufactured.

  In the present embodiment, the second wavelength conversion member 26 is formed with a substantially uniform thickness along the outer periphery of the light emitting element 20. Therefore, color unevenness can be effectively suppressed for the light emitted outside without being scattered on the surface of the recess 16a. Further, the upper surface of the first wavelength conversion member 24 is formed wider than the second wavelength conversion member 26. Thereby, a part of the upper surface of the first wavelength conversion member 24 is exposed to the outside of the second wavelength conversion member 26, and light can be directly extracted also from the upper surface of the second wavelength conversion member 26.

Embodiment 3
FIG. 8 is a schematic cross-sectional view showing a light-emitting device according to Embodiment 3 of the present invention. In the present embodiment, both the first wavelength conversion member 24 and the second wavelength conversion member 26 are plate-like, and the side surfaces of the semiconductor light emitting element 20 are exposed without being covered with the wavelength conversion substance 30. Further, via holes are provided in the first wavelength conversion member 24 and the support member 32, and electrical connection is established with the wirings 12a and 12b of the mounting substrate through the conductive material 50 filled therein. Other points are the same as in the first embodiment.

  The wavelength conversion member 30 in the present embodiment includes a first wavelength conversion member 24 that contacts the lower surface of the light emitting element 20 and a second wavelength conversion member 26 that contacts the upper surface of the light emitting element 20. The second wavelength conversion member 26 preferably has an outer dimension in the planar direction larger than that of the light emitting element 20 and projects from the outer periphery of the light emitting element 20 in a bowl shape. Thereby, the emitted light from the upper surface of the light emitting element 20 can be extracted outside after passing through the second wavelength conversion member 26. For example, when the size of the second wavelength conversion member 26 is the same as that of the light emitting element 20, the light beam emitted obliquely upward from the side surface of the light emitting layer 38 does not pass through the second wavelength conversion member 26 and In some cases, the surface of the recess 16a may not be scattered. Therefore, as shown in FIG. 8, if the second wavelength conversion member 26 is made larger than the light emitting element 20 so as to project in a bowl shape from the outer periphery of the light emitting element 20, the light is emitted from the light emitting layer 38 of the light emitting element 20. Of the light, the light that is not scattered by the recess 16a can surely pass through the second wavelength conversion member 16a. In addition, if the 2nd wavelength conversion member 30 protrudes from the outer periphery of the light emitting element 20 to such an extent that this can be achieved, the magnitude | size and planar shape of a 2nd wavelength conversion member will not be specifically limited. However, if the second wavelength conversion member 26 is too large, the light scattered by the recess 16a will pass through the second wavelength conversion member 26 again, causing uneven color and a decrease in light emission output. The maximum dimension in the planar direction of the second wavelength conversion member 26 in the present embodiment is 1.1 times or more, preferably 1.5 or more times the maximum dimension in the planar direction of the light emitting layer 38 of the light emitting element 20, and It is desirable to make it 3 times or less, preferably 2 times or less.

  If the second wavelength conversion member 26 has a plate-like shape and protrudes like a ridge from the light emitting element 20 as in the present embodiment, the wavelength of the side surface of the light emitting element 20 is reduced while suppressing the problem of color unevenness. It can be exposed from the conversion member 30. When the side surface of the light emitting element 20 is exposed without being covered with the wavelength conversion member 30, the light returning to the inside of the light emitting element 20 can be further reduced, and deterioration of the second wavelength conversion member 26 due to heat generation of the light emitting element 20 can be suppressed. . That is, when the second wavelength conversion member 26 covers the upper surface and the side surface of the light emitting element 20, the light is scattered by the phosphor particles contained in the second wavelength conversion member 26. There is a considerable percentage of light returning. If the side surface of the light emitting element 20 is exposed without being covered with the wavelength conversion member 30 as in the present embodiment, the probability that light emitted from the side surface of the light emitting element 20 returns to the light emitting element 20 is greatly reduced, and light emission is performed. The light emitted from the element 20 can be taken out more efficiently. Further, since the contact area between the second wavelength conversion member 26 and the light emitting element 20 is also reduced, deterioration of the second wavelength conversion member 26 due to heat generation of the light emitting element 26 can be suppressed.

  In the conventional light emitting device, when the side surface of the light emitting element 20 is simply exposed without being covered with the wavelength conversion member 30, the light emitted from the side surface of the light emitting element 20 is extracted outside without passing through the wavelength conversion member 30. Therefore, strong color unevenness occurs. In the case of a light emitting device in which the inside of the recess is sealed by the sealing member 28, some light is totally reflected at the interface between the sealing member 28 and air and returned to the inside of the recess, but strong color unevenness still remains. . In the present embodiment, since the light emitted from the side surface of the light emitting element 20 is scattered by the concave portion 16a and mixed with the light whose wavelength is converted by the wavelength conversion member 20, the problem of uneven color generation can be prevented.

  Also in the present embodiment, the scattering surface 18 formed on the surface of the recess 16a is preferably formed in as wide a range as possible, but it is desirable to form at least a part of the side surface of the recess 16a, more preferably the entire side surface. . Thereby, uneven color can be effectively suppressed. That is, one of the causes of the color unevenness is a difference in optical path length when the light emitted from the light emitting element 20 passes through the wavelength conversion member 30. The light traveling from the light emitting element 20 toward the bottom surface of the concave portion 16a is light irradiated from the front surface of the wavelength conversion member 30, so that the optical path length of the wavelength conversion member 30 is relatively uniform and color unevenness is unlikely to occur. On the other hand, light that travels obliquely from the light emitting element 20 toward the side surface of the recess 16a is light that travels obliquely and exits the wavelength conversion member 30, and therefore depends on the optical path length of the wavelength conversion member 30. Color unevenness is likely to occur. Moreover, when the wavelength conversion member 30 is plate-shaped, a part of light in the wavelength conversion member 30 is totally reflected by two opposing main surfaces, and is emitted from the side surface. For this reason, the light emitted from the side surface has a large optical path length in the wavelength conversion member, and the intensity of the wavelength conversion light tends to increase, and in principle, color unevenness is likely to occur.

  In particular, when the side surface of the light emitting element 20 is exposed without being covered with the wavelength conversion member 30 as in the present embodiment, color unevenness due to light emitted from the side surface of the light emitting element 20 is likely to occur. However, in the case of the light emitting element 20 installed parallel to the bottom surface of the recess 16a, the light emitted from the side surface of the light emitting element 20 is most incident on the region facing the side surface of the light emitting layer 38 among the side surfaces of the recess 16a. Easy to do. Therefore, it is preferable to form the scattering surface so as to include a region facing the side surface of the light emitting layer 38 among the side surfaces of the recess 16a. Thereby, the color nonuniformity which generate | occur | produces when the side surface of the light emitting element 20 is exposed without being covered with the wavelength conversion member can also be suppressed effectively.

  Similarly to the first wavelength conversion member 24 in the first embodiment, the second wavelength conversion member 26 in the present embodiment is preferably made of an inorganic material. By configuring the second wavelength conversion member 26 with such a material, the durability of the second wavelength conversion member 26 itself increases, and at the same time, the mechanical strength of the second wavelength conversion member 26 also increases. As described above, it is easy to form a plate shape and project from the outer periphery of the light emitting element 20 in a bowl shape. If the first wavelength conversion member 24 and the second wavelength conversion member 26 are made of the same material, it is possible to reduce the manufacturing cost due to the common use of the members, and the difference in thermal expansion coefficient applied to the top and bottom of the light emitting element 20. The stress due to the light becomes uniform, which helps to improve the reliability of the light emitting device 10.

  In the present embodiment, via holes are provided in the first wavelength conversion member 24 and the support member 32, and electrical connection is established with the wirings 12 a and 12 b on the mounting substrate through the conductive material 50 filled therein. The conductive material 50 and the wiring 12a, 12b of the mounting substrate may be joined with an appropriate material such as solder or metal eutectic. As in this embodiment, by directly connecting the light emitting element 20 and the wirings 12a and 12b of the mounting substrate through the conductive material 50, the heat dissipation of the light emitting element 20 is further improved. As the conductive material 50, a material having high thermal conductivity and high conductivity is preferably used. For example, Cu, Ag, Au, Ni, or the like can be used. Further, by filling the via hole with such a conductive material 50, the conductive material 50 can be used as a reflecting portion. Thereby, the light inside the first wavelength conversion member 24 and the support member 32 can be reflected and extracted to the scattering surface 18 side.

  Further, when a light-shielding member that substantially blocks light, such as a metal member, is provided inside the support member as in the present embodiment, the light-shielding member is located at a position overlapping the light emitting element 20 in a top view. Is preferably arranged. This is because when a light-shielding member such as a metal member is disposed outside the light emitting element 20, only light in a specific direction is blocked with respect to the light emitting element 20, and color unevenness appears strongly. In addition, as shown in FIG. 8, the light-emitting element 20 that is flip-chip mounted usually has a reflective electrode formed on the mounting surface side. Therefore, even if a light-shielding member is provided immediately below the light-emitting element 20, the light-emitting element 20 The amount of light extracted directly under the light is small, and the light emitted from the light emitting element 20 is hardly disturbed.

  The above embodiments are merely examples, and the present invention is not limited to these. In addition, each element of the present invention is not limited to the case of being configured with the members described in the above embodiment, and a plurality of elements of the invention may be configured with a single member, or one element may be configured with a plurality of members. You can also

DESCRIPTION OF SYMBOLS 10 Light-emitting device 12 Mounting board 12a, 12b Wiring 14 Side wall 16 Package 16a Recess 17 Particle 18 Scattering surface 20 Light-emitting element 24 First wavelength conversion member 26 Second wavelength conversion member 28 Sealing member 30 Wavelength conversion member 32 Support member 34 Substrate 36 n-type nitride semiconductor layer 38 light emitting layer 40 p-type nitride semiconductor layer 42 n-side electrode 44 p-side ohmic electrode 46 p-side pad electrode 48 protective insulating film 50 conductive member 52 solder 54 phosphor particle 55 phosphor holding member 56 phosphor layer 72 light emitting semiconductor chip assembly 74 phosphor chip 76 adhesive 78 light emitting diode chip 80 substrate 82 phosphor layer 84 anode electrode 86 cathode electrode 88 anode lead 90 cathode lead 90a cup unit 92 light emitting device 94 light scattering agent 96 Protective adhesive

Claims (9)

A light emitting element having a semiconductor as a light emitting layer and a wavelength conversion member that absorbs part of the light emitted from the light emitting element and emits light of a different wavelength in a container having a recess having an upper surface opened, the light emission A light-emitting device that mixes the light emission of the element and the light emission of the wavelength conversion member and emits the light from the opening of the recess,
The wavelength conversion member has a first wavelength conversion member and a second wavelength conversion member,
On the bottom surface of the container, the first wavelength conversion member, the light emitting element, and the second wavelength conversion member are sequentially directed toward the opening of the recess through a translucent support member. Formed so as to be separated from the side surface of the recess,
The first wavelength conversion member is a plate-like member in which an inorganic binder made of an inorganic material and a phosphor are combined,
A scattering surface is formed on the side surface of the concave portion at least in a portion irradiated with light emitted parallel to the main surface of the first wavelength conversion member from the side surface of the first wavelength conversion member. A light emitting device characterized.   2. The light emitting device according to claim 1, wherein the second wavelength conversion member is formed by dispersing a phosphor in a translucent resin.   The difference in refractive index between the translucent resin and the phosphor in the second wavelength conversion member is larger than the difference in refractive index between the inorganic binder and the phosphor in the first wavelength conversion member. The light-emitting device according to claim 2.   The light emitting device according to any one of claims 1 to 3, wherein the first wavelength conversion member is thicker than the light emitting element.   5. The light emitting device according to claim 1, wherein the first wavelength conversion member is thicker than the second wavelength conversion member.   The density | concentration of the fluorescent substance contained in a said 1st wavelength conversion member is higher than the density | concentration of the fluorescent substance contained in a said 2nd wavelength conversion member, The any one of Claim 1 thru | or 5 characterized by the above-mentioned. Light-emitting device.   The light emitting device according to claim 1, wherein an upper surface and a side surface of the light emitting element are covered with the second wavelength conversion member.   The light-emitting device according to claim 1, wherein a side surface of the first wavelength conversion member is not covered with the second wavelength conversion member.   Of the upper surface of the first wavelength conversion member, the vicinity of the light emitting element is covered with the second wavelength conversion member, while the vicinity of the outer periphery of the first wavelength conversion member is covered with the second wavelength conversion member. The light-emitting device according to claim 1, wherein the light-emitting device is not broken.

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