Light emitting device and method for manufacturing the same

Abstract

To provide a light-emitting device and a manufacturing method thereof which are capable of reducing the size of the light-emitting device.SOLUTION: A light-emitting device 100 comprises: a light-emitting element 10 including a support substrate 15, and a first light-emitting portion 11 and a second light-emitting portion 12 disposed adjacently to each other; a wavelength conversion member 20 to perform wavelength conversion of first light emitted from the first light-emitting portion 11 and second light emitted from the second light-emitting portion 12 into third light; and a light adjustment member 30 overlapping one of the first light-emitting portion 11 and the second light-emitting portion 12 in plan view. In the light-emitting element 10, the emission intensity of the first light at a light emission peak wavelength of the second light is lower than the emission intensity of the second light at the light emission peak wavelength of the second light, during light emission of the light-emitting device 100.SELECTED DRAWING: Figure 1C

Description

[Technical field]

[0001] The present disclosure relates to a light emitting device and a method for manufacturing the same. [Background technology]

[0002] In recent years, LEDs have been used as light sources for vehicle lighting such as headlights. For example, Patent Document 1 discloses a light emitting device that has a light distribution pattern suitable for a headlight by combining multiple light emitting elements with different areas. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-011259 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a light emitting device that can achieve miniaturization of the light emitting device and a method for manufacturing the same. [Means for solving the problem]

[0005] A light emitting device according to an embodiment of the present disclosure is a light emitting device including: a support substrate having a first surface and a second surface opposite to the first surface; a light emitting element disposed on the second surface of the support substrate, the light emitting element having a first light emitting section and a second light emitting section disposed adjacent to each other, each of the first light emitting section and the second light emitting section including a semiconductor stack having, in order, a first semiconductor layer, a light emitting layer, and a second semiconductor layer; a wavelength conversion member disposed on the first surface of the support substrate, the wavelength conversion member including a phosphor that converts the wavelength of a first light emitted from the first light emitting section and a second light emitted from the second light emitting section into a third light; and a light adjustment member disposed on a surface of the wavelength conversion member opposite to the surface facing the support substrate, the light emitting element overlapping either the first light emitting section or the second light emitting section in a planar view, wherein the light emitting element is configured such that, when the light emitting device emits light, the emission intensity of the first light at the emission peak wavelength of the second light is smaller than the emission intensity of the second light at the emission peak wavelength of the second light.

[0006] A manufacturing method of a light emitting device according to an embodiment of the present disclosure includes the steps of: preparing a light emitting element having a supporting substrate having a first surface and a second surface opposite to the first surface; and a first light emitting portion and a second light emitting portion arranged adjacent to each other, each of which includes a semiconductor stack having a first semiconductor layer, a light emitting layer, and a second semiconductor layer, in that order; preparing a wavelength conversion member having a first surface and a second surface opposite to the first surface, the wavelength conversion member including a phosphor that converts the wavelength of a first light emitted from the first light emitting portion and a second light emitted from the second light emitting portion into a third light, and a light adjustment member arranged on a first surface of the wavelength conversion member; and arranging the wavelength conversion member on which the light adjustment member is arranged such that the second surface of the wavelength conversion member faces the first surface of the supporting substrate, and the step of arranging the wavelength conversion member includes arranging the light adjustment member at a position overlapping either the first light emitting portion or the second light emitting portion in a planar view. Effect of the Invention

[0007] According to the embodiments of the present disclosure, it is possible to provide a light emitting device that can achieve miniaturization of the light emitting device and a method for manufacturing the same. [Brief description of the drawings]

[0008] [Figure 1A] FIG. 1 is a perspective view illustrating an example of a light emitting device according to a first embodiment. [Figure 1B] FIG. 1 is a plan view illustrating an example of a light emitting device according to a first embodiment. [Figure 1C] 1C is a schematic cross-sectional view taken along line IC-IC in FIG. 1B. [Figure 1D] FIG. 2 is a bottom view illustrating an example of a light emitting element in the light emitting device according to the first embodiment. [Figure 1E] 1 is a cross-sectional view illustrating a schematic example of a light-emitting element in the light-emitting device according to the first embodiment. [Figure 1F] FIG. 2 is a schematic plan view for explaining a wiring substrate in the light emitting device according to the first embodiment. [Figure 1G] FIG. 2 is a plan view illustrating an example of a wiring substrate in the light emitting device according to the first embodiment. [Figure 2A] 3 is a schematic cross-sectional view for explaining the path of light from a light-emitting portion in the light-emitting device according to the first embodiment. FIG. [Figure 2B] FIG. 2B is a simplified schematic cross-sectional view of FIG. 2A. [Diagram 3] 4 is a flowchart of a method for manufacturing the light emitting device according to the first embodiment. [Figure 4A] 3A to 3C are cross-sectional views illustrating an example of a method for manufacturing the light emitting device according to the first embodiment. [Figure 4B] 3A to 3C are cross-sectional views illustrating an example of a method for manufacturing the light emitting device according to the first embodiment. [Figure 4C] 3A to 3C are cross-sectional views illustrating an example of a method for manufacturing the light emitting device according to the first embodiment. [Figure 4D] 3A to 3C are cross-sectional views illustrating an example of a method for manufacturing the light emitting device according to the first embodiment. [Figure 4E] 3A to 3C are cross-sectional views illustrating an example of a method for manufacturing the light emitting device according to the first embodiment. [Figure 5A] FIG. 11 is a plan view illustrating an example of a light emitting device according to a second embodiment. [Figure 5B]5B is a schematic cross-sectional view taken along line VB-VB in FIG. 5A. [Figure 6A] FIG. 11 is a plan view illustrating an example of a light emitting device according to a third embodiment. [Figure 6B] FIG. 6B is a schematic cross-sectional view taken along line VIB-VIB in FIG. 6A. [Figure 6C] FIG. 11 is a bottom view diagrammatically illustrating an example of a light emitting element in the light emitting device according to the third embodiment. [Figure 6D] FIG. 11 is a cross-sectional view illustrating an example of a light-emitting element in a light-emitting device according to a third embodiment. [Figure 6E] FIG. 13 is a schematic plan view for explaining a wiring substrate in a light emitting device according to a third embodiment. [Figure 6F] FIG. 11 is a plan view illustrating an example of a wiring substrate in a light emitting device according to a third embodiment. [Figure 7A] FIG. 13 is a plan view illustrating an example of a light emitting device according to a fourth embodiment. [Figure 7B] FIG. 7B is a schematic cross-sectional view taken along line VIIB-VIIB in FIG. 7A. [Figure 8A] FIG. 13 is a schematic cross-sectional view for explaining the path of light from a light-emitting portion in a light-emitting device according to a fourth embodiment. [Figure 8B] FIG. 8B is a schematic cross-sectional view that simplifies FIG. 8A. [Figure 9A] FIG. 13 is a plan view illustrating an example of a light emitting device according to a fifth embodiment. [Figure 9B] 9B is a schematic cross-sectional view taken along line IXB-IXB in FIG. 9A. [Figure 10A] FIG. 13 is a plan view illustrating an example of a light emitting device according to a sixth embodiment. [Figure 10B] 10B is a schematic cross-sectional view taken along line XB-XB in FIG. 10A. [Figure 11A] FIG. 13 is a cross-sectional view illustrating an example of a light emitting device according to a seventh embodiment. [Figure 11B] FIG. 13 is a cross-sectional view illustrating an example of a light emitting device according to an eighth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The embodiment will be described below with reference to the drawings. However, the following embodiments are illustrative of a light-emitting device and a method for manufacturing a light-emitting device for embodying the technical idea of ​​the present embodiment, and are not limited to the following. Furthermore, the dimensions, materials, shapes, and relative positions of the components described in the embodiments are merely illustrative, and are not intended to limit the scope of the present invention, unless otherwise specified. The size and positional relationship of the components shown in each drawing may be exaggerated or simplified to clarify the explanation. In addition, in order to avoid the drawings becoming overly complicated, some elements may be omitted from the illustration, or an end view showing only the cut surface may be used as a cross-sectional view. Furthermore, "covering" is not limited to direct contact, but also includes indirect covering, for example, through other members. Furthermore, "disposing" is not limited to direct contact, but also includes indirect disposing, for example, through other members.

[0010] First Embodiment [Light emitting device] FIG. 1A is a perspective view showing an example of the light emitting device according to the first embodiment. FIG. 1B is a plan view showing an example of the light emitting device according to the first embodiment. FIG. 1C is a schematic cross-sectional view taken along the IC-IC line in FIG. 1B. FIG. 1D is a bottom view showing an example of a light emitting element in the light emitting device according to the first embodiment. FIG. 1E is a cross-sectional view showing an example of a light emitting element in the light emitting device according to the first embodiment. FIG. 1F is a schematic plan view for explaining a wiring board in the light emitting device according to the first embodiment. FIG. 1G is a plan view for explaining an example of a wiring board in the light emitting device according to the first embodiment. FIG. 2A is a schematic cross-sectional view for explaining a path of light from a light emitting unit in the light emitting device according to the first embodiment. FIG. 2B is a schematic cross-sectional view that simplifies FIG. 2A.

[0011] The light emitting device 100 includes: a support substrate 15 having a first surface 15a and a second surface 15b opposite the first surface 15a; a light emitting element 10 arranged on the second surface 15b of the support substrate 15 and having a first light emitting section 11 and a second light emitting section 12 arranged adjacent to each other, each of which includes a semiconductor laminate having first semiconductor layers 111, 121, light emitting layers 112, 122, and second semiconductor layers 113, 123, in that order; a wavelength conversion member 20 arranged on the first surface 15a of the support substrate 15 and including a phosphor that converts the wavelength of a first light emitted from the first light emitting section 11 and a second light emitted from the second light emitting section 12 into a third light; and a light adjustment member 30 arranged on a surface (i.e., the first surface 20a of the wavelength conversion member 20) opposite to the surface of the wavelength conversion member 20 facing the support substrate 15 (i.e., the second surface 20b of the wavelength conversion member 20) and overlapping either the first light emitting section 11 or the second light emitting section 12 in a planar view. When the light emitting device 100 emits light, the emission intensity of the first light at the emission peak wavelength of the second light is smaller than the emission intensity of the second light at the emission peak wavelength of the second light.

[0012] As an example, the light emitting device 100 will be described as further including a light guiding member 40 covering the side surface of the support substrate 15, a wiring board 50 on which the light emitting element 10 is arranged, and a covering member 60 covering the side surface of the light emitting element 10 and the side surface of the wavelength conversion member 20 via the light guiding member 40. Each component of the light emitting device 100 will now be described.

[0013] (Light emitting element) The light-emitting element 10 includes a plurality of light-emitting sections. Specifically, the light-emitting element 10 includes a support substrate 15, a first light-emitting section 11 and a second light-emitting section 12 arranged adjacent to each other on a second surface 15b of the support substrate 15, a first element electrode 16 arranged on the first light-emitting section 11, and a second element electrode 17 arranged on the second light-emitting section 12. A first light is emitted from the first light-emitting section 11 of the light-emitting element 10, and a second light is emitted from the second light-emitting section 12. Examples of the support substrate 15 include insulating substrates such as sapphire and spinel (MgAl2O4), and nitride-based semiconductor substrates such as InN, AlN, GaN, InGaN, AlGaN, and InGaAlN. Note that, in order to extract the light emitted from the light emitting portion through the support substrate 15, it is preferable that the support substrate 15 is made of a material having translucency.

[0014] The first light emitting section 11 and the second light emitting section 12 each include a semiconductor laminate. The semiconductor laminate of the first light emitting section 11 and the second light emitting section 12 includes first semiconductor layers 111 and 121, light emitting layers 112 and 122, and second semiconductor layers 113 and 123, which are arranged in this order on the support substrate 15. A buffer layer made of AlGaN or the like may be arranged between the support substrate 15 and the semiconductor laminate. The first light emitting section 11 and the second light emitting section 12 are arranged adjacent to each other with a gap on the second surface 15b of the support substrate 15. The first light emitting section 11 and the second light emitting section 12 each have an element electrode for supplying power from the outside arranged on the semiconductor laminate side. Here, the first light emitting section 11 has three element electrodes arranged as the first element electrode 16, that is, an N-side electrode 161, a P-side electrode 162, and an N-side electrode 163. Similarly, the second light-emitting section 12 has three element electrodes arranged as the second element electrode 17: an N-side electrode 171, a P-side electrode 172, and an N-side electrode 173. In the light-emitting element 10, the first light-emitting section 11 and the second light-emitting section 12 are separated from each other and are electrically independent. Therefore, the first light-emitting section 11 and the second light-emitting section 12 can be driven individually by supplying power to each of them via the first element electrode 16 and the second element electrode 17, respectively.

[0015] The first light-emitting section 11 and the second light-emitting section can be selected from those that emit light of any wavelength depending on the application. For example, the first light-emitting section 11 and / or the second light-emitting section 12 that emits light of blue (for example, wavelength 430 to 500 nm) or green (for example, wavelength 500 to 570 nm) can be made of a nitride-based semiconductor (In X Al Y Ga 1-X-YN, 0≦X, 0≦Y, X+Y≦1), GaP, etc. can be used. The first light emitting section 11 and / or the second light emitting section 12 that emits red light (for example, wavelength 610 to 700 nm) can use, as the semiconductor laminate, GaAlAs, AlInGaP, etc. in addition to a nitride-based semiconductor element. The first light emitting section 11 and the second light emitting section 12 may have the same semiconductor laminate structure or different semiconductor laminate structures.

[0016] When the light emitting device 100 emits light, the light emitting element 10 can make the emission intensities of the first light and the second light emitted from the first light emitting section 11 and the second light emitting section 12 different from each other. An example of a light-emitting element having a first light-emitting section 11 and a second light-emitting section 12 having different light-emitting intensities during light emission is a light-emitting element 10 having different semiconductor laminates as the first light-emitting section 11 and the second light-emitting section 12. Even if the first light-emitting section 11 and the second light-emitting section 12 have the same semiconductor laminate, the light-emitting element 10 can have a first light-emitting section 11 and a second light-emitting section 12 having different light-emitting intensities during light emission of the light-emitting device 100 by making the current density of the current passing through the light-emitting layer 112 of the first light-emitting section 11 and the current density of the current passing through the light-emitting layer 122 of the second light-emitting section 12 different. Here, the light-emitting element 10 has the same semiconductor laminate structure in the first light-emitting section 11 and the second light-emitting section 12. Then, power is supplied to the light-emitting element 10 so that the current density passing through the light-emitting layer 122 of the second light-emitting section 12 during light emission of the light-emitting device 100 is higher than the current density passing through the light-emitting layer 112 of the first light-emitting section 11.

[0017] The first light-emitting section 11 emits a first light. The second light-emitting section 12 emits a second light having a different emission intensity at the emission peak wavelength from the first light. In the light-emitting element 10, the emission intensity of the first light at the emission peak wavelength of the second light is smaller than the emission intensity of the second light at the emission peak wavelength of the second light when the light-emitting device 100 emits light. For example, if the emission peak wavelength of the second light is 439 nm, the emission intensity of the first light is smaller than the emission intensity of the second light at this wavelength of 439 nm. By making the emission intensities of the first light and the second light different, it is possible to make a difference between the luminance of the first light-emitting section 11 side and the luminance of the second light-emitting section 12 side on the light-emitting surface of the light-emitting device 100. As a result, for example, when the light-emitting device 100 is used as a light source for a headlight of an automobile, the luminance can be adjusted according to the irradiation area of ​​the headlight even with a relatively simple optical system configuration. In the light emitting device 100, one light emitting element 10 includes a first light emitting section 11 and a second light emitting section 12 that emit light with different light emitting intensities. This allows the light emitting device 100 to be made smaller than a light emitting device that combines a plurality of light emitting elements to provide a luminance difference on the light emitting surface. For example, when the light emitting device 100 is used as a light source for an automobile headlight, the light emitting surface can be made smaller, so that optical components such as lenses and reflectors can be made smaller, enabling the headlight to be made smaller, and improving the freedom of design.

[0018] The emission peak wavelengths of the first light and the second light during emission are, for example, 420 nm or more and 460 nm or less. The emission spectra of the first light and the second light partially overlap, but the emission peak wavelengths are different. The difference between the emission peak wavelengths of the first light and the second light during emission is preferably 0.1 nm or more and 15 nm or less. If the difference in the emission peak wavelengths is 0.1 nm or more, it is easier to make a difference in luminance. On the other hand, if the difference in the emission peak wavelengths is 15 nm or less, it is easier to suppress uneven chromaticity on the light-emitting surface of the light-emitting device 100 during emission by the light adjustment member 30 described later. When the emission intensity of the second light during emission is 100, the emission intensity of the first light of the light-emitting device 100 is 0 to 80, and preferably 10 to 70. If the emission intensity of the first light is 10 or more, it is easier to suppress the difference in chromaticity on the light-emitting surface of the light-emitting device 100. On the other hand, if the emission intensity of the first light is 70 or less, it is easier to make a difference in luminance on the light-emitting surface.

[0019] The first light-emitting section 11 and the second light-emitting section 12 have the same area in a plan view. The first light-emitting section 11 and the second light-emitting section 12 have different current densities during light emission. The light-emitting device 100 can differentiate the emission intensities of the first light and the second light by differentiating the current densities during light emission between the first light-emitting section 11 and the second light-emitting section 12. The current density during light emission can be made different by individually driving the first light-emitting section 11 and the second light-emitting section 12 via the wiring 52 of the wiring board 50, as described later.

[0020] In the light emitting device 100, the current density during emission of light from the first light emitting section 11 is lower than the current density of the second light emitting section 12. As a result, the emission intensity of the second light emitted from the second light emitting section 12 is higher than the emission intensity of the first light emitted from the first light emitting section 11. This makes it easier for the light emitting device 100 to achieve a difference in luminance. Specifically, the current density during emission of light from the first light emitting section 11 is 0 A / m 2 More than 1.9 x 10 6 A / m 2 or less, the current density during light emission of the second light-emitting section 12 is higher than the current density during light emission of the first light-emitting section 11, and is 1.7×10 6A / m 2 More than 2.8 x 10 6 A / m 2 The following are included:

[0021] (Wavelength conversion material) The light emitting device 100 is provided with a wavelength conversion member 20 arranged on a first surface 15a of a supporting substrate 15 and containing a phosphor that converts the wavelength of a first light emitted from a first light emitting section 11 and a second light emitted from a second light emitting section 12 into a third light. The wavelength conversion member 20 converts at least a part of the light from the light emitting element 10 into a different wavelength. Here, as an example, the wavelength conversion member 20 is plate-shaped and rectangular in a plan view. The wavelength conversion member 20 includes a phosphor that converts the wavelength of the first light and the second light into a third light having a different emission peak wavelength from the first light and the second light. The emission peak wavelength of the third light is, for example, 500 nm or more and 600 nm or less. The wavelength conversion member 20 has a wavelength conversion layer 21 containing a phosphor and a light-transmitting member 22 supporting the wavelength conversion layer 21, and the wavelength conversion layer 21 is disposed facing the first surface 15a of the support substrate 15. Moreover, a surface of the wavelength conversion member 20 that is larger than the first surface 15a of the support substrate 15 is bonded to the first surface 15a of the support substrate 15. That is, the wavelength conversion member 20 is disposed such that the outer edge of the wavelength conversion member 20 is positioned outside the outer edge of the light emitting element 10 in a planar view.

[0022] The wavelength conversion layer 21 may be formed by mixing a phosphor and a light-transmitting material, such as a resin, glass, or inorganic material, as a binder. Examples of the light-transmitting material that may be used include organic resin materials, such as epoxy resin, silicone resin, phenol resin, and polyimide resin, and inorganic materials, such as glass and ceramic.

[0023] As the phosphor, one that can be excited by the first light and the second light emitted from the first light emitter 11 and the second light emitter 12 is used. For example, a phosphor that emits green light is an yttrium-aluminum-garnet phosphor (e.g., Y3(Al,Ga)5O 12:Ce), lutetium-aluminum-garnet-based phosphor (e.g., Lu3(Al,Ga)5O 12 :Ce), terbium-aluminum-garnet-based phosphor (e.g., Tb3(Al,Ga)5O 12 :Ce), silicate-based phosphor (e.g., (Ba,Sr)2SiO4:Eu), chlorosilicate-based phosphor (e.g., Ca8Mg(SiO4)4C l2 :Eu), β-sialon-based phosphor (e.g., Si 6-z Al z O z N 8-z :Eu(0 < z < 4.2)), SGS-based phosphor (e.g., SrGa2S4:Eu), etc. can be mentioned. As the yellow-emitting phosphor, α-sialon-based phosphor (e.g., Mz(Si,Al) 12 (O,N) 16 (where 0 < z ≤ 2, and M is Li, Mg, Ca, Y, and lanthanide elements excluding Ce) etc. can be mentioned. In addition, among the above green-emitting phosphors, there are also yellow-emitting phosphors. Also, for example, yttrium-aluminum-garnet-based phosphor can shift the emission peak wavelength to the long wavelength side by substituting a part of Y with Gd, and yellow emission is possible. Also, among these, there are fluorescent substances capable of orange emission. As the red-emitting phosphor, nitrogen-containing calcium aluminosilicate (CASN or SCASN)-based phosphor (e.g., (Sr,Ca)AlSiN3:Eu), BSESN-based phosphor (e.g., (Ba,Sr,Ca)2Si5N8:Eu), etc. can be mentioned. In addition, manganese-activated fluoride-based phosphor (general formula (I) A2[M 1-a Mn a F6] represented phosphor (where in the above general formula (I), A is at least one selected from the group consisting of K, Li, Na, Rb, Cs, and NH4, M is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and a satisfies 0 < a < 0.2)) can be mentioned. Examples of this manganese-activated fluoride-based phosphor include KSF-based phosphor (e.g., K2SiF6:Mn), KSAF-based phosphor (e.g., K2Si 0.99 Al 0.01 F 5.99:Mn) and MGF-based phosphors (e.g., 3.5MgO 0.5MgF2 GeO2:Mn).

[0024] For example, as a yellow-emitting phosphor that can be combined with a blue-emitting element to emit a mixed white-color light, there is an yttrium-aluminum-garnet phosphor in which part of the Y is replaced with Gd (e.g., (Y,Gd)3Al5O 12 In order to obtain a light emitting device 100 capable of emitting white light, the type and concentration of the phosphor contained in the wavelength conversion layer 21 are adjusted so that the light emitting device 100 can emit white light of a desired chromaticity rank.

[0025] The phosphor concentration of the wavelength conversion layer 21 is preferably set according to the second light having a high luminous intensity emitted from the second light emitter 12. Specifically, it is preferably set according to the peak wavelength when the second light is emitted. For example, the type, particle size, and concentration of the phosphor to be contained are determined according to the peak wavelength of the second light when emitted at a desired luminous intensity, taking into consideration the wavelength conversion efficiency excited at the peak wavelength and the luminous wavelength. The phosphor concentration of the wavelength conversion layer 21 is preferably, for example, 60% by mass or more and 70% by mass or less. The phosphor concentration indicates the proportion of the phosphor in the wavelength conversion layer 21 containing the phosphor.

[0026] The light-transmitting member 22 may be a plate-shaped light-transmitting material such as resin, glass, or inorganic material. The light-transmitting member 22 is disposed so that its lower surface abuts against the upper surface of the wavelength conversion layer 21, with a size equivalent to that of the wavelength conversion layer 21 in a plan view. As the glass, for example, borosilicate glass, quartz glass, or the like may be used, and as the resin, for example, silicone resin, epoxy resin, or the like may be used. In particular, it is preferable to use glass for the light-transmitting member 22 in consideration of its resistance to deterioration by light, mechanical strength, and the like. The light-transmitting member 22 may contain a light-diffusing member. By containing a light-diffusing member in the light-transmitting member 22, it is possible to suppress uneven chromaticity and uneven brightness. As the light-diffusing member, for example, titanium oxide, barium titanate, aluminum oxide, silicon oxide, or the like may be used. An example of the wavelength conversion member 20 is a configuration in which the wavelength conversion layer 21 is disposed by printing or the like on a light-transmitting member 22 made of a glass plate. Since the wavelength conversion layer 21 is supported by the glass plate, the wavelength conversion layer 21 can be made thinner. This shortens the optical path length of light passing through the wavelength conversion layer 21, suppresses attenuation of light in the wavelength conversion layer 21, and enables the light-emitting device 100 to have higher brightness. Furthermore, by disposing glass on the light-emitting surface side of the light-emitting device 100, the surface unevenness of the light-transmitting member 22 can be reduced, making it easier to dispose the light adjustment member 30.

[0027] The thickness of the wavelength conversion member 20 can be, for example, from 100 μm to 300 μm, and preferably from 150 μm to 250 μm, taking into consideration the miniaturization of the light emitting device 100 and the mechanical strength of the wavelength conversion member 20. When the wavelength conversion member 20 includes the wavelength conversion layer 21 and the light-transmitting member 22, the thickness of the wavelength conversion layer 21 is preferably about 20% to 60% of the total thickness of the wavelength conversion member 20.

[0028] (Light adjustment material) The light emitting device 100 includes a light adjusting member 30 that is disposed on a surface 20a (hereinafter referred to as a first surface 20a of the wavelength converting member 20) opposite to a surface 20b (hereinafter referred to as a second surface 20b of the wavelength converting member 20) on the support substrate side of the wavelength converting member 20, and overlaps either the first light emitting section 11 or the second light emitting section 12 in a planar view. The light adjusting member 30 reflects light of a specific wavelength, for example, and transmits light of other wavelengths. In other words, the light adjusting member 30 is an optical member that has both reflective and translucent optical properties. This allows the chromaticity of the light emitted from the light emitting device 100 to be adjusted. The light adjusting member 30 may reflect all of the light of the specific wavelength, or may reflect a part of the light of the specific wavelength. The light adjusting member 30 is a member that reflects the third light and transmits the first light. The light adjusting member 30 is, for example, a dielectric multilayer film. Here, the light adjusting member 30 transmits a part of the third light.

[0029] As the dielectric multilayer film, for example, a distributed Bragg reflector film (DBR) can be used. Specifically, it is a film in which two or more types of dielectric films having different refractive indices are alternately laminated with a thickness of wavelength / 4n (n is the refractive index), and can reflect light of a predetermined wavelength with high efficiency. Examples of the dielectric film include silicon oxide, niobium oxide, aluminum oxide, titanium oxide, zirconium oxide, and tantalum oxide. Examples of the dielectric multilayer film include a film in which silicon oxide films and niobium oxide films are alternately laminated. For example, the reflectance and / or transmittance can be controlled by changing the film thickness and material of the low refractive index layer and the high refractive index layer.

[0030] In this embodiment, the refractive index of the low refractive index layer is preferably in the range of 1.2 or more and 1.6 or less, and the refractive index of the high refractive index layer is preferably in the range of 2.0 or more and 2.6 or less. When one set is made up of the above two layers stacked together, it is preferable to form a film in 10 sets or more. Here, in the case of light interference (especially when they cancel each other out), the relationship "2nd=λ / 2" is established when n is the refractive index, d is the film thickness, and λ is the wavelength. This allows the film thicknesses of the low refractive index layer and the high refractive index layer to be specified. Specifically, when the refractive index of silicon oxide is 1.46, the refractive index of niobium oxide is 2.25, and the wavelength to be cut is 600 nm (±100 nm), the film thickness of one silicon oxide film is, for example, 103 nm, and the film thickness of one niobium oxide film is, for example, 67 nm.

[0031] The light adjustment member 30 is disposed at a position overlapping the first light-emitting section 11 in a plan view. By disposing the light adjustment member 30 at a position overlapping the first light-emitting section 11 that emits the first light in a plan view, it is possible to suppress the emission of the third light obtained by wavelength-converting the first light and the third light obtained by wavelength-converting the second light on the first light-emitting section 11 side from the light-emitting device 100. This makes it possible to reduce the difference in chromaticity between the light emitted from the first light-emitting section 11 side and the light emitted from the second light-emitting section 12 side. This makes it possible for the light-emitting device 100 to improve unevenness in chromaticity of the emitted color on the light-emitting surface.

[0032] The light adjustment member 30 is preferably disposed at a position overlapping with the entire first light-emitting section 11 in plan view. This can further suppress the third light obtained by wavelength conversion of the first light from being emitted from the light-emitting device 100. However, the light adjustment member 30 may have a portion not overlapping with the first light-emitting section 11 in plan view as long as it can obtain the effect of adjusting the chromaticity to a desired level. The light adjustment member 30 is preferably disposed at a position overlapping the first light-emitting section 11 in a plan view, and is also preferably disposed to extend to a position near the center between the first light-emitting section 11 and the second light-emitting section 12. This makes it possible to further suppress the third light obtained by wavelength-converting the first light, and the third light obtained by wavelength-converting the second light on the first light-emitting section 11 side, from being emitted from the light-emitting device 100.

[0033] (Light guiding components) The light emitting device 100 may include a light guide member 40 that covers the side surface of the light emitting element 10 . The light guiding member 40 is a member that guides light from the light emitting element 10 to the wavelength conversion member 20. The light guiding member 40 covers the side surface of the support substrate 15. The light guiding member 40 may be, for example, an adhesive member that bonds the light emitting element 10 and the wavelength conversion member 20 to each other and extends to the side surface of the support substrate 15. In this case, the light guiding member 40 may be disposed between the support substrate 15 and the wavelength conversion member 20 with a predetermined thickness. Furthermore, the light guiding member 40 may be a member different from the adhesive member between the light emitting element 10 and the wavelength conversion member 20.

[0034] As an example, the shape of the light guide member 40 is curved in cross-sectional view. The shape of the light guide member 40 may have a shape in which the side is inclined so that the width increases from the second surface 15b side of the support substrate 15 toward the second surface 20b side of the wavelength conversion member 20 in cross-sectional view. The cross-sectional shape of the side of the light guide member 40 may be a straight shape or a curved shape. For example, when the side of the light guide member 40 in cross-sectional view is curved, the curved shape may be a curved shape recessed toward the covering member 60 side described later, or may be a curved shape recessed toward the supporting substrate 15 side. Furthermore, the shape may have a portion recessed toward the covering member 60 side and a portion recessed toward the supporting substrate 15 side.

[0035] For example, a light-transmitting resin can be used as the light guide member 40. For example, an organic resin such as an epoxy resin, a silicone resin, a phenol resin, or a polyimide resin can be used as the light guide member 40. Among them, it is preferable to use a silicone resin having high heat resistance. In addition, the light guide member 40 may contain the above-mentioned light diffusing member or phosphor.

[0036] (wiring board) In the light emitting device 100 , the light emitting element 10 can be disposed on a wiring substrate 50 . The wiring board 50 includes a base material 51 and wiring 52 disposed on the upper surface of the base material 51 and supplying power to the first element electrode 16 and the second element electrode 17 of the light emitting element 10 via a conductive member 70. The first element electrode 16 and the second element electrode 17 are disposed on the wiring 52 via the conductive member 70. The conductive member 70 can be made of a metal material made of a conductive metal, for example, Cu, Au, or an alloy of each of these metals. The light emitting element 10 and the wiring 52 may be directly bonded to each other without the conductive member 70 being interposed therebetween. The wiring board 50 includes wiring 52 capable of driving the first light-emitting section 11 and the second light-emitting section 12 individually. The wiring 52 includes, for example, a first wiring 521, a second wiring 522, and a third wiring 523 for driving the first light-emitting section 11, and a fourth wiring 524, a fifth wiring 525, and a sixth wiring 526 for driving the second light-emitting section 12. The first wiring 521 and the third wiring 523 are connected by a wire 53, and the fourth wiring 524 and the sixth wiring 526 are connected by a wire 54. In addition, electronic components 541 such as protective elements are disposed on the second wiring 522 and the third wiring 523, and electronic components 542 are disposed on the fifth wiring 525 and the sixth wiring 526. With such wiring 52, the wiring board 50 can individually control the magnitude of the current supplied to the first light-emitting section 11 and the second light-emitting section 12.

[0037] The substrate 51 may be made of a material known in the art as a substrate for forming a wiring board for supporting electronic components such as light-emitting elements. Examples of the substrate include insulating materials such as glass epoxy, resin, and ceramics, semiconductor materials such as silicon, and conductive materials such as copper. Among them, ceramics having high heat resistance and light resistance are preferably used. Examples of ceramics include aluminum oxide, aluminum nitride, silicon nitride, and LTCC. Composite materials of these insulating materials, semiconductor materials, and conductive materials may also be used. When a semiconductor material or conductive material is used as the substrate 51, the wiring 52 may be disposed on the upper surface of the substrate 51 via an insulating layer. Examples of materials for the wiring 52 include metals such as Fe, Cu, Ni, Al, Ag, Au, Pt, Ti, W, and Pd, and alloys containing at least one of these metals.

[0038] (Covering material) The light emitting device 100 can include a covering member 60 that covers the light emitting element 10 and the wavelength converting member 20 . The covering member 60 is disposed so as to cover the side surfaces of the first element electrode 16 and the second element electrode 17, and the side surface of the wavelength conversion member 20. When the light emitting device 100 includes a light guiding member 40, the covering member 60 covers the side surfaces of the light emitting element 10 via the light guiding member 40. Furthermore, when the light emitting element 10 is disposed on a wiring board 50, the covering member 60 may cover the upper surface of the wiring board 50. The covering member 60 preferably has a light blocking property, specifically, preferably has a light reflecting property and / or a light absorbing property. In particular, it preferably contains a material that can suitably reflect the light emitted from the light emitting element 10. For example, it preferably has a reflectance of 60% or more with respect to the first light and the second light emitted from the light emitting element 10, and more preferably has a reflectance of 70% or more, 80% or more, or 90% or more. The covering member 60 is preferably made of an insulating material. For example, a thermosetting resin, a thermoplastic resin, or the like can be used as the covering member 60. Specifically, the covering member 60 can be made of a resin containing particles of a light-reflecting substance. Examples of the resin include a resin or hybrid resin containing one or more of silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, acrylic resin, phenol resin, bismaleimide triazine resin, and polyphthalamide resin. Among them, a resin containing a silicone resin as a base polymer, which has excellent heat resistance, electrical insulation, and flexibility, is preferable. Examples of the light-reflecting substance include titanium oxide, silicon oxide, zirconium oxide, magnesium oxide, calcium carbonate, calcium hydroxide, calcium silicate, zinc oxide, barium titanate, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, mullite, and combinations thereof. Among them, titanium oxide is preferable because it is relatively stable against moisture and has a high refractive index.

[0039] [Light emitting device operation] When the light emitting device 100 is driven, a current is supplied from an external power source to the light emitting element 10, and the light emitting element 10 emits light. At least a part of the first light and the second light emitted from the light emitting element 10 is wavelength-converted to the third light by the wavelength conversion member 20. The third light is mixed with the first light and the second light that have not been wavelength-converted to the third light, and is irradiated to the outside as, for example, white light. In addition, the light traveling in the lateral direction from the light emitting element 10 is reflected by the covering member 60, enters the wavelength conversion member 20, and is irradiated to the outside. At this time, as described above, the first light and the second light have different emission intensities, and the phosphor concentration of the wavelength conversion layer 21 is set according to the second light emitted from the second light emitting section 12, which has a high emission intensity. In other words, the phosphor concentration of the wavelength conversion layer 21 is higher than the phosphor concentration when it is set to a desired white color according to the first light. Therefore, the proportion of the third light emitted from the first light emitting section 11 side in the wavelength conversion member 20 increases. Then, by arranging the light adjustment member 30 at a position overlapping with the first light-emitting section 11 in a plan view, it is possible to adjust the amount of the third light emitted from the first light-emitting section 11 side in a plan view. This reduces the chromaticity difference between the light emitted from the first light-emitting section 11 side and the light emitted from the second light-emitting section 12 side, and it is possible to improve the chromaticity unevenness on the light-emitting surface of the light-emitting device 100.

[0040] The improvement of chromaticity unevenness of emitted color by the light adjustment member 30 will be specifically described below with reference to Figures 2A and 2B. Note that Figures 2A and 2B only show a schematic of some of the light paths to simplify the description. The actual light travels in a different direction between and within each member due to refraction, scattering, etc., but for simplicity, illustrations of such changes may be omitted. The light emitted from the light-emitting layer has a peak emission wavelength that shifts depending on the strength of the current flowing through the light-emitting layer. For example, increasing the current value shifts the peak emission wavelength to the short wavelength side. Therefore, even if the first light-emitting section 11 and the second light-emitting section 12 are the same semiconductor laminate, if the current values ​​supplied to the first light-emitting section 11 and the second light-emitting section 12 are different, the difference in the peak emission wavelength will cause a difference in the excitation efficiency of the phosphor, resulting in a difference in the chromaticity of the emitted light.

[0041] The emission peak wavelengths of the first light and the second light (e.g., blue light) emitted from the first light-emitting unit 11 and the second light-emitting unit 12 are longer for the first light L1B1 having a lower emission intensity than for the second light L2B1 having a higher emission intensity. In this case, the emission peak wavelength of the wavelength-converted light (e.g., yellow light) is longer for the third light L1Y11 obtained by wavelength-converting the first light L1B1 than for the third light L2Y11 obtained by wavelength-converting the second light L2B1. The phosphor concentration of the wavelength conversion layer 21 is set according to the second light L2B1 having a higher emission intensity emitted from the second light-emitting unit 12. For this reason, the phosphor concentration is higher for the first light L1B1, and more of the first light L1B1 is easily wavelength-converted into the third light L1Y11.

[0042] Then, by disposing the light adjustment member 30 at a position overlapping the first light-emitting unit 11 in a plan view, on the first light-emitting unit 11 side, a part of the third light L1Y11 obtained by wavelength-converting the first light L1B1 traveling upward is reflected by the light adjustment member 30 to become the third light L1Y12, and another part of the third light L1Y11 passes through the light adjustment member 30 and is emitted as the third light L1Y13 from the upper surface of the light adjustment member 30. Note that the third light L2Y21 obtained by wavelength-converting the second light L2B2 traveling diagonally upward on the first light-emitting unit 11 side, which is emitted from the second light-emitting unit 12, is mostly reflected by the light adjustment member 30 to become the third light L2Y22, and the remaining third light L2Y21 passes through the light adjustment member 30 to be emitted as the third light L2Y23 from the upper surface of the light adjustment member 30.

[0043] On the other hand, on the second light-emitting unit 12 side, the third light L2Y11 is emitted as is from the upper surface of the wavelength conversion member 20. Note that the third light L1Y21 obtained by wavelength-converting the first light L1B2 that is emitted from the first light-emitting unit 11 and travels diagonally upward toward the second light-emitting unit 12 side is emitted as is from the upper surface of the wavelength conversion member 20. At this time, the third light L1Y11 has a longer wavelength (i.e., closer to yellow) than the third light L2Y11. Therefore, the chromaticity of the light emitted from the first light-emitting unit 11 side is adjusted by reflecting a part of the third light L1Y11 (yellow light) by the light adjustment member 30. This reduces the chromaticity difference between the light emitted from the first light-emitting unit 11 side and the light emitted from the second light-emitting unit 12 side, and improves the chromaticity unevenness of white light with luminance differences emitted from the light-emitting device 100.

[0044] [Manufacturing method of light emitting device] Fig. 3 is a flowchart of a method for manufacturing the light emitting device according to embodiment 1. Fig. 4A to Fig. 4E are cross-sectional views that typically show an example of a method for manufacturing the light emitting device according to embodiment 1.

[0045] A method for manufacturing the light emitting device 100 includes the steps of preparing a light emitting element 10 having a support substrate 15 having a first surface 15a and a second surface 15b opposite to the first surface 15a, and a first light emitting portion 11 and a second light emitting portion 12 arranged adjacent to each other and including a semiconductor laminate having first semiconductor layers 111 and 121, light emitting layers 112 and 122, and second semiconductor layers 113 and 123, in that order, on the second surface 15b of the support substrate 15; The method includes the steps of: preparing a wavelength conversion member 20 having a second surface 20b opposite to the surface 20a, the wavelength conversion member 20 including a phosphor that converts the wavelength of a first light emitted from the first light-emitting section 11 and a second light emitted from the second light-emitting section 12 into a third light, and arranging the wavelength conversion member 20 having the light adjustment member 30 arranged on the first surface 15a of the support substrate 15 such that the second surface 20b of the wavelength conversion member 20 faces the first surface 15a of the support substrate 15. The step of arranging the wavelength conversion member 20 arranges the wavelength conversion member 20 on the light-emitting element 10 such that the light adjustment member 30 is arranged at a position overlapping with either the first light-emitting section 11 or the second light-emitting section 12 in a plan view.

[0046] The manufacturing method of the light emitting device 100 is described as including a step S11 of preparing a light emitting element, a step S12 of preparing a wavelength conversion member, a step S13 of arranging the wavelength conversion member, a step S14 of arranging the light emitting element, and a step S15 of arranging a covering member. The materials and arrangement of each member are the same as those described above in connection with the light emitting device 100, and therefore will not be described here as appropriate.

[0047] (Process for preparing light-emitting element) The step S11 of preparing a light emitting element is a step of preparing a light emitting element 10 having a support substrate 15, a first light emitting section 11, a second light emitting section 12, a first element electrode 16 and a second element electrode 17.

[0048] (Step of preparing wavelength conversion member) The step S12 of preparing a wavelength conversion member is a step of arranging a light adjustment member 30 on the first surface 20a of the wavelength conversion member 20 to prepare the wavelength conversion member 20 on which the light adjustment member 30 is arranged. The light adjustment member 30 may be formed by stacking dielectric films on the first surface 20a of the wavelength conversion member 20 to form a dielectric multilayer film. Alternatively, the wavelength conversion member 20 on which the light adjustment member 30 such as a dielectric multilayer film is arranged in advance may be prepared by purchasing or the like. When the wavelength conversion member 20 has a structure including a wavelength conversion layer 21 containing a phosphor and a translucent member 22 supporting the wavelength conversion layer 21, it is preferable to arrange the dielectric multilayer film on the translucent member 22 with the translucent member 22 side facing the first surface 20a. In addition, in the process S12 of preparing the wavelength conversion member, the arrangement, size, etc. of each member are adjusted so that when the wavelength conversion member 20 is placed on the first surface 15a of the support substrate 15, the light adjustment member 30 is placed in a position overlapping the first light-emitting section 11 in a planar view. Incidentally, step S11 of preparing a light emitting element and step S12 of preparing a wavelength conversion member may be performed in either order, or may be performed in parallel.

[0049] (Step of arranging wavelength conversion member) The step S13 of arranging the wavelength conversion member is a step of arranging the wavelength conversion member 20 having the light adjustment member 30 arranged on the first surface 15a of the support substrate 15. In the step S12 of arranging the wavelength conversion member, the wavelength conversion member 20 having the wavelength conversion layer 21 containing a phosphor and the light-transmitting member 22 supporting the wavelength conversion layer 21 is arranged so that the surface on the wavelength conversion layer 21 side is located on the first surface 15a side of the support substrate 15. In the step S13 of arranging the wavelength conversion member, the wavelength conversion member 20 is arranged so that the light adjustment member 30 is arranged at a position overlapping the first light-emitting unit 11 in a planar view. Wavelength conversion member 20 is bonded to support substrate 15 using, for example, an adhesive member. At this time, by adjusting the amount of adhesive member, the adhesive member provided between support substrate 15 and wavelength conversion member 20 can be extended to the side surface of support substrate 15, and light guiding member 40, which is an adhesive member, can be formed on the side surface of support substrate 15. Note that wavelength conversion member 20 may be bonded to support substrate 15 by a direct bonding method without using an adhesive member.

[0050] (Step of arranging light-emitting elements) The step S14 of arranging the light-emitting element is a step of arranging the light-emitting element 10 on the wiring substrate 50. In the step S14 of arranging the light-emitting element, the first element electrode 16 and the second element electrode 17 are joined to the wiring 52 using the conductive member 70, thereby arranging the light-emitting element 10 on the wiring substrate 50.

[0051] (Step of placing covering member) The step S15 of arranging a covering member is a step of arranging a covering member 60 on the wiring board 50 to cover the side surfaces of the first element electrodes 16 and the second element electrodes 17, the side surface of the light guide member 40, and the side surface of the wavelength conversion member 20. In the step S15 of disposing the covering member, uncured resin constituting the covering member 60 is disposed on the wiring board 50 so as to cover all of the side surfaces of the wavelength conversion member 20. The resin, etc. can be disposed, for example, by filling the resin on the upper side of the fixed wiring board 50 using a resin discharge device that can be moved (moved) in the vertical or horizontal direction relative to the wiring board 50. It is also possible to dispose the resin, etc. by a compression molding method, a transfer molding method, etc. Thereafter, the resin is cured to form the covering member 60. Note that the covering member 60 may be formed by disposing a frame such as a resin wall in advance at a desired position on the wiring board 50 and supplying the resin into the frame. Also, the upper surface of the formed covering member 60 may be cut as necessary to adjust the height or to flatten the upper surface of the covering member 60.

[0052] In the method of manufacturing the light emitting device 100, a plurality of light emitting devices 100 may be manufactured simultaneously or individually using a single wiring board having a plurality of continuous regions that become the wiring boards 50 of the individual light emitting devices 100 after singulation. When a plurality of light emitting devices 100 are manufactured simultaneously, a singulation step is performed after the step S15 of arranging the covering member is completed, in which the light emitting devices 100 are singulated into individual light emitting devices 100, and the light emitting devices 100 are formed.

[0053] Next, another embodiment will be described. Note that the same reference numerals are used to denote the same components as those already described, and the description thereof will be omitted as appropriate.

[0054] <Second embodiment> Fig. 5A is a plan view showing an example of a light emitting device according to a second embodiment, and Fig. 5B is a schematic cross-sectional view taken along line VB-VB in Fig. 5A.

[0055] The light emitting device 100A differs from the light emitting device 100 of the first embodiment in that the light adjustment member 30A is arranged to extend to a position overlapping a part of the second light emitting section 12 in a plan view. The light adjustment member 30A is disposed so as to overlap the first light-emitting section 11 in a plan view, and is disposed so as to extend to a position overlapping approximately half of the second light-emitting section 12. With this configuration, it is possible to further suppress the third light obtained by wavelength-converting the first light from being emitted from the light-emitting device 100A.

[0056] <Third embodiment> Fig. 6A is a plan view showing an example of the light emitting device according to the third embodiment. Fig. 6B is a schematic cross-sectional view taken along line VIB-VIB in Fig. 6A. Fig. 6C is a bottom view showing an example of a light emitting element in the light emitting device according to the third embodiment. Fig. 6D is a cross-sectional view showing an example of a light emitting element in the light emitting device according to the third embodiment. Fig. 6E is a schematic plan view for explaining a wiring board in the light emitting device according to the third embodiment. Fig. 6F is a plan view showing an example of a wiring board in the light emitting device according to the third embodiment.

[0057] In the light emitting device 100B, the first light emitting portion 11A and the second light emitting portion 12A of the light emitting element 10A have different areas in a plan view compared to the configuration of the light emitting device 100 of the first embodiment. Specifically, the light emitting surface of the first light emitting portion 11A is larger than the light emitting surface of the second light emitting portion 12A in a plan view. This makes it possible to make the current density during light emission different between the first light emitting portion 11A and the second light emitting portion 12A, even if the wiring board 50A includes wiring 52A that connects the first light emitting portion 11A and the second light emitting portion 12A in series.

[0058] The semiconductor laminate of the first light emitting section 11A and the second light emitting section 12A includes, from the support substrate 15 side, first semiconductor layers 111A and 121A, light emitting layers 112A and 122A, and second semiconductor layers 113A and 123A. The first light emitting section 11A and the second light emitting section 12A are arranged adjacent to each other with a gap on the second surface 15b of the support substrate 15. The first light emitting section 11A has three electrodes arranged as the first element electrode 16A, namely, an N-side electrode 161A, a P-side electrode 162A, and an N-side electrode 163A. Similarly, the second light emitting section 12A has three electrodes arranged as the second element electrode 17A, namely, an N-side electrode 171A, a P-side electrode 172A, and an N-side electrode 173A. The first element electrode 16A and the second element electrode 17A have sizes corresponding to the difference in area between the first light emitting section 11A and the second light emitting section 12A.

[0059] The wiring board 50A includes a wiring 52A that connects the first light-emitting portion 11A and the second light-emitting portion 12A in series. The wiring 52A includes, for example, a first wiring 521A, a second wiring 522A, and a third wiring 523A. A P-side electrode 172A is arranged on the first wiring 521A, an N-side electrode 161A and an N-side electrode 163A are arranged on the second wiring 522A, and a P-side electrode 162A, an N-side electrode 171A, and an N-side electrode 173A are arranged on the third wiring 523A. In addition, an electronic component 543 is arranged on the first wiring 521A and the second wiring 522A. With such wiring 52A, the wiring board 50A can make the current density during light emission different between the first light-emitting portion 11A and the second light-emitting portion 12A.

[0060] <Fourth embodiment> Fig. 7A is a plan view showing an example of a light emitting device according to a fourth embodiment. Fig. 7B is a schematic cross-sectional view taken along line VIIB-VIIB in Fig. 7A. Fig. 8A is a schematic cross-sectional view for explaining a path of light from a light emitting unit in the light emitting device according to the fourth embodiment. Fig. 8B is a schematic cross-sectional view that simplifies Fig. 8A.

[0061] The light emitting device 100C differs from the light emitting device 100 of the first embodiment in that the concentration of phosphor in the wavelength conversion layer 21A of the wavelength conversion member 20A is low. Also, the light adjustment member 31 is a member that reflects the second light and transmits the third light, and is arranged at a position overlapping with the second light-emitting section 12 in a planar view. In this arrangement, in step S13 of arranging the wavelength conversion member, the wavelength conversion member 20A is arranged so that the light adjustment member 31 is arranged at a position overlapping with the second light-emitting section 12 in a planar view.

[0062] The phosphor concentration in the wavelength conversion layer 21A is preferably set in accordance with the first light having a low luminous intensity emitted from the first light emitter 11. Specifically, it is preferably set in accordance with the peak wavelength of light emitted by the first light emitter 11. The phosphor concentration in the wavelength conversion layer 21A is preferably set to, for example, 50 mass % or more and 60 mass % or less.

[0063] In this embodiment, the refractive index of the low refractive index layer is preferably in the range of 1.2 or more and 1.6 or less, and the refractive index of the high refractive index layer is preferably in the range of 2.0 or more and 2.6 or less. When one set is made up of the above two layers stacked together, it is preferable to form a film in 10 sets or more. In addition, if the refractive index of silicon oxide is 1.46, the refractive index of niobium oxide is 2.25, and the wavelength to be cut is 400 nm (±100 nm), the thickness of one silicon oxide film is, for example, 68 nm, and the thickness of one niobium oxide film is, for example, 44 nm.

[0064] In addition, the ratio of the phosphor concentration (low concentration) in the wavelength conversion layer 21A of the light emitting device 100C to the phosphor concentration (high concentration) in the wavelength conversion layer 21 of the light emitting device 100C is preferably approximately 100 (low concentration):101-120 (high concentration) when the emission intensity ratio of the weak emission to the strong emission of the light emitting section is 1-20:100. Specifically, for example, when the current difference between the light-emitting sections is 0.1 A (weak emission): 1 A (strong emission), the peak wavelength difference is +2.1 nm (weak emission): 0 nm (strong emission), and the chromaticity y difference is about +0.015: 0. Increasing the phosphor concentration by 8 mass % causes the chromaticity y to vary by about +0.018, so the phosphor concentration ratio should be about 100 (low concentration): 108 (high concentration).

[0065] In the light emitting device 100C, the second light having a high emission intensity emitted from the second light emitting section 12 is less likely than desired to be converted into the third light by the wavelength conversion layer 21A, compared to the first light having a low emission intensity emitted from the first light emitting section 11. In addition, the emission peak wavelength of the wavelength-converted light is longer for the third light obtained by wavelength-converting the first light than for the third light obtained by wavelength-converting the second light. Therefore, by arranging the light adjusting member 31 at a position overlapping the second light emitting section 12 that emits the second light in a plan view, it is possible to suppress the emission of the second light that has not been wavelength-converted and the first light that has not been wavelength-converted and is emitted from the second light emitting section 12 side from the light emitting device 100C, thereby improving chromaticity unevenness.

[0066] The improvement of chromaticity unevenness of emitted color by the light adjustment member 31 will be specifically described below with reference to Figures 8A and 8B. Note that Figures 8A and 8B only show a schematic of some of the light paths to simplify the description. The actual light travels in a different direction between and within each member due to refraction, scattering, etc., but for simplicity, illustrations of such changes may be omitted. The emission peak wavelengths of the first light and the second light (e.g., blue light) emitted from the first light emitter 11 and the second light emitter 12 are longer for the first light L1B1 having a lower emission intensity than for the second light L2B1 having a higher emission intensity. In this case, the emission peak wavelength of the wavelength-converted light (e.g., yellow light) is shorter for the third light L2Y11 obtained by wavelength-converting the second light L2B1 than for the third light L1Y11 obtained by wavelength-converting the first light L1B1. The phosphor concentration of the wavelength conversion layer 21 is set, for example, according to the first light L1B1 having a lower emission intensity emitted from the first light emitter 11. For this reason, the phosphor concentration is lower for the second light L2B1, and more of the second light L2B1 passes through the wavelength conversion layer 21A without being wavelength-converted.

[0067] Then, by arranging the light adjustment member 31 at a position overlapping the second light emitting unit 12 in a plan view, on the second light emitting unit 12 side, a part of the second light L2B1 traveling upward is reflected by the light adjustment member 31 to become the second light L2B11. Then, another part of the second light L2B1 passes through the light adjustment member 31 and is emitted from the upper surface of the light adjustment member 31 as the second light L2B12. Also, the third light L2Y11 obtained by wavelength conversion of the second light L2B1 is emitted as it is from the upper surface of the light adjustment member 31. Note that most of the first light L1B2 traveling obliquely upward from the first light emitting unit 11 to the second light emitting unit 12 side is reflected by the light adjustment member 31 to become the first light L1B21, and the remaining first light L1B2 passes through the light adjustment member 31 and is emitted from the upper surface of the light adjustment member 31 as the first light L1B22. Moreover, the third light L1Y21 obtained by converting the wavelength of the first light L1B2 is emitted from the upper surface of the light adjusting member 31 as it is.

[0068] On the other hand, on the first light-emitting unit 11 side, the first light L1B1 and the third light L1Y11 obtained by wavelength-converting the first light L1B1 are emitted as they are from the upper surface of the wavelength conversion member 20. The second light L2B2 emitted from the second light-emitting unit 12 and directed obliquely upward toward the first light-emitting unit 11 side, and the third light L2Y21 obtained by wavelength-converting the second light L2B2 are emitted as they are from the upper surface of the wavelength conversion member 20. At this time, since the third light L2Y11 has a shorter wavelength (i.e., closer to blue) than the third light L1Y11, the chromaticity of the light emitted from the second light-emitting unit 12 side is adjusted by reflecting a part of the second light L2B1 (blue light) by the light adjustment member 31. This reduces the chromaticity difference between the light emitted from the first light-emitting unit 11 side and the light emitted from the second light-emitting unit 12 side, and improves the chromaticity unevenness of white light with luminance differences emitted from the light-emitting device 100C.

[0069] <Fifth embodiment> Fig. 9A is a plan view showing an example of a light emitting device according to embodiment 5. Fig. 9B is a schematic cross-sectional view taken along line IXB-IXB in Fig. 9A.

[0070] The light emitting device 100D differs from the light emitting device 100C of the fourth embodiment in that the light adjustment member 31A is disposed so as to extend to a position overlapping a part of the first light emitting portion 11 in a plan view. The light adjustment member 31A is disposed so as to overlap the second light-emitting section 12 in a plan view, and is disposed so as to extend to a position overlapping approximately half of the first light-emitting section 11. With this configuration, it is possible to further prevent the first light and the second light that have not been wavelength-converted by the wavelength conversion layer 21A from being emitted from the light-emitting device 100C.

[0071] Sixth embodiment Fig. 10A is a plan view showing an example of a light emitting device according to a sixth embodiment, and Fig. 10B is a schematic cross-sectional view taken along line XB-XB in Fig. 10A.

[0072] The light emitting device 100E is different from the light emitting device 100C of the fourth embodiment in that the light emitting surface of the first light emitting portion 11A is larger than the light emitting surface of the second light emitting portion 12A in a plan view. The wiring board 50A includes wiring 52A that connects the first light emitting portion 11A and the second light emitting portion 12A in series, and the wiring 52A can be sized to correspond to the difference in area between the first light emitting portion 11A and the second light emitting portion 12A. This makes it possible to make the current density during light emission different between the first light emitting portion 11A and the second light emitting portion 12A, even if the wiring board 50A includes wiring 52A that connects the first light emitting portion 11A and the second light emitting portion 12A in series.

[0073] Seventh embodiment FIG. 11A is a cross-sectional view illustrating an example of a light emitting device according to a seventh embodiment.

[0074] The light emitting device 100F differs from the light emitting device 100 of the first embodiment in that the wavelength conversion member 20B is composed of one wavelength conversion layer. The wavelength conversion member 20B may be, for example, a single layer of the wavelength conversion layer 21 described in the light emitting device 100. The wavelength conversion member 200B may also be a sintered body of a phosphor. The phosphor concentration of the wavelength conversion member 20B is preferably, for example, 90 mass % or more and 100 mass % or less. The phosphor concentration indicates the ratio of the phosphor to the total amount of the wavelength conversion member 20B including the phosphor. The wavelength conversion member 20B may also contain a light diffusing member as necessary.

[0075] Eighth embodiment FIG. 11B is a cross-sectional view that illustrates an example of the light emitting device according to the eighth embodiment.

[0076] The light emitting device 100G is different from the light emitting device 100C of the fourth embodiment in that the wavelength conversion member 20C is made of one wavelength conversion layer. The wavelength conversion member 20C may be, for example, a single layer of the wavelength conversion layer 21A described in the light emitting device 100C. The wavelength conversion member 20C may also be a sintered body of a phosphor. The phosphor concentration of the wavelength conversion member 20C is preferably, for example, 80 mass % or more and 90 mass % or less. The phosphor concentration indicates the ratio of the phosphor to the total amount of the wavelength conversion member 20C including the phosphor. A light diffusing member may also be added to the wavelength conversion member 20C as necessary.

[0077] The light emitting device and the manufacturing method thereof according to the present embodiment have been specifically described above by way of the embodiment of the invention, but the gist of the present invention is not limited to these descriptions and should be broadly interpreted based on the claims. In addition, various changes and modifications based on these descriptions are also included in the gist of the present invention. In addition, the above-mentioned embodiments can be implemented in combination with each other.

[0078] For example, the light emitting device may have three or more light emitting sections. The number of element electrodes arranged on one light emitting section may be two or four or more. The light guiding member and the covering member may not be included. The wavelength conversion member may have three or more layers. In this case, the phosphor concentration may be the ratio of the phosphor to the total amount of the entire layer including the phosphor in the wavelength conversion member. When the first light emitting section and the second light emitting section have the same area in a plan view, the current density during light emission of the first light emitting section and the second light emitting section may be different by arranging a constant current diode on a wiring board having wiring connecting the first light emitting section and the second light emitting section in series. Even when the area of ​​the first light emitting section and the second light emitting section is different in a plan view, the current density during light emission of the first light emitting section and the second light emitting section may be different by driving the first light emitting section and the second light emitting section separately.

[0079] In addition, in the manufacturing method of the light emitting device, the order of some steps is not limited, and the order may be changed. For example, the wavelength conversion member may be placed on the light emitting element, and then the light adjustment member may be placed on the wavelength conversion member. Also, the light adjustment member may be placed on the wavelength conversion member, and then the covering member may be placed on the wiring board. Also, the wavelength conversion member may be placed on the light emitting element, and then the light emitting element may be placed on the wiring board.

[0080] The light emitting device and the manufacturing method thereof according to the embodiment of the present disclosure are, for example, as follows. [Section 1] a light emitting element including: a support substrate having a first surface and a second surface opposite to the first surface; and a first light emitting section and a second light emitting section disposed on the second surface of the support substrate, each of the first light emitting section and the second light emitting section including a semiconductor laminate having a first semiconductor layer, a light emitting layer, and a second semiconductor layer in that order, the first light emitting section and the second light emitting section being disposed adjacent to each other; a wavelength conversion member disposed on a first surface of the support substrate, the wavelength conversion member including a phosphor that converts the wavelength of the first light emitted from the first light-emitting unit and the second light emitted from the second light-emitting unit into a third light; a light adjusting member that is disposed on a surface of the wavelength conversion member opposite to a surface of the wavelength conversion member on the support substrate side and overlaps one of the first light emitting unit and the second light emitting unit in a plan view, The light emitting element is a light emitting device in which, when the light emitting device is emitting light, the emission intensity of the first light at the emission peak wavelength of the second light is smaller than the emission intensity of the second light at the emission peak wavelength of the second light. [Section 2] 2. The light emitting device according to item 1, wherein the wavelength conversion member includes a wavelength conversion layer containing the phosphor and a light-transmitting member supporting the wavelength conversion layer. [Section 3] an emission peak wavelength of the first light is longer than an emission peak wavelength of the second light; the light adjusting member reflects the third light and transmits the first light, 3. The light emitting device according to item 1 or 2, wherein the light adjustment member is disposed at a position overlapping the first light emitting portion in a plan view. [Section 4] an emission peak wavelength of the first light is longer than an emission peak wavelength of the second light; the light adjusting member reflects the second light and transmits the third light, 3. The light emitting device according to item 1 or 2, wherein the light adjustment member is disposed at a position overlapping the second light emitting portion in a plan view. [Section 5] 5. The light emitting device according to any one of items 1 to 4, wherein the first light emitting section and the second light emitting section have different current densities during light emission. [Section 6] 6. The light emitting device according to item 5, wherein the first light emitting section and the second light emitting section have the same area in a plan view. [Section 7] 6. The light emitting device according to item 5, wherein the first light emitting section and the second light emitting section have different areas in a plan view. [Section 8] a wiring substrate on which the light emitting element is disposed, Item 8. The light emitting device according to item 6 or 7, wherein the wiring board includes wiring capable of driving the first light emitting section and the second light emitting section individually. [Section 9] a wiring substrate on which the light emitting element is disposed, 8. The light emitting device according to item 7, wherein the wiring board includes wiring that connects the first light emitting portion and the second light emitting portion in series. [Section 10] Item 10. The light emitting device according to any one of items 1 to 9, wherein the light adjustment member is arranged to overlap one of the first light emitting section and the second light emitting section in a planar view and extends to a position where it overlaps a portion of the other of the first light emitting section and the second light emitting section. [Section 11] 11. The light emitting device according to any one of items 1 to 10, wherein the light adjustment member is a dielectric multilayer film. [Section 12] Item 12. The light emitting device according to any one of items 1 to 11, wherein when an emission intensity of the second light during emission is taken as 100, an emission intensity of the first light is 10 or more and 70 or less. [Section 13] Item 13. The light emitting device according to any one of items 1 to 12, wherein the first light and the second light have emission peak wavelengths of 420 nm or more and 460 nm or less, and the third light has an emission peak wavelength of 500 nm or more and 600 nm or less during emission. [Section 14] Item 14. The light emitting device according to any one of items 1 to 13, wherein a difference between an emission peak wavelength of the first light and an emission peak wavelength of the second light during emission is 0.1 nm or more and 15 nm or less. [Section 15] A step of preparing a light emitting element including: a support substrate having a first surface and a second surface opposite to the first surface; and a first light emitting portion and a second light emitting portion disposed adjacent to each other on the second surface of the support substrate, each of the first light emitting portion and the second light emitting portion including a semiconductor laminate having, in order, a first semiconductor layer, a light emitting layer, and a second semiconductor layer; preparing a wavelength conversion member having a first surface and a second surface opposite to the first surface, the wavelength conversion member including a phosphor that converts the wavelength of a first light emitted from the first light-emitting unit and a second light emitted from the second light-emitting unit into a third light, and a light adjustment member disposed on the first surface of the wavelength conversion member; and arranging the wavelength conversion member on which the light adjustment member is arranged such that a second surface of the wavelength conversion member faces a first surface of the support substrate, A method for manufacturing a light emitting device, wherein the step of arranging the wavelength conversion member comprises arranging the light adjustment member at a position overlapping either the first light emitting section or the second light emitting section in a plan view. [Section 16] the wavelength conversion member includes a wavelength conversion layer including the phosphor and a light-transmitting member supporting the wavelength conversion layer, Item 16. The method for manufacturing a light emitting device according to item 15, wherein the step of arranging the wavelength conversion member comprises arranging the wavelength conversion member so that a surface of the wavelength conversion layer side is located on a first surface side of the support substrate. [Section 17] the light adjusting member reflects the third light and transmits the first light, Item 17. The method for manufacturing a light emitting device according to item 15 or 16, wherein the step of arranging the wavelength conversion member comprises arranging the light adjustment member at a position overlapping the first light emitting portion in a plan view. [Section 18] the light adjusting member reflects the second light and transmits the third light, Item 17. The method for manufacturing a light emitting device according to item 15 or 16, wherein the step of arranging the wavelength conversion member comprises arranging the light adjustment member at a position overlapping the second light emitting portion in a plan view. [Industrial Applicability]

[0081] The light emitting device according to the embodiment of the present disclosure can be suitably used for vehicle lighting such as headlights, etc. In addition, the light emitting device according to the embodiment of the present disclosure can be used as a backlight source for liquid crystal displays, various lighting fixtures, large displays, various display devices such as advertisements and destination guides, and further, image reading devices in digital video cameras, facsimiles, copy machines, scanners, etc., projector devices, etc. [Explanation of symbols]

[0082] 15 Support substrate 15a 1st page 15b Side 2 10, 10A light emitting element 11, 11A First light emitting part 12, 12A Second light emitting part 111, 111A first semiconductor layer 121, 121A first semiconductor layer 112, 112A Light-emitting layer 122, 122A Light-emitting layer 113, 113A second semiconductor layer 123, 123A Second semiconductor layer 16, 16A First element electrode 17, 17A Second element electrode 161, 161A N side electrode 162, 162A P side electrode 163, 163A N side electrode 171, 171A N side electrode 172, 172A P side electrode 173, 173A N side electrode 20, 20A, 20B, 20C Wavelength conversion material 20a Page 1 20b 2nd side 21, 21A Wavelength conversion layer 22 Translucent material 30, 30A Light adjustment material 31, 31A Light adjustment member 40 Light guide member 50, 50A wiring board 51 Base material 52, 52A Wiring 521, 521A 1st wiring 522, 522A 2nd wiring 523, 523A 3rd wiring 524 4th wiring 525 5th wiring 526 6th wiring 53 Wire 54 Wire 541, 542, 543 Electronic Components 60 Covering material 70 Conductive materials 100, 100B, 100C, 100D, 100E, 100F, 100G Light-emitting device

Claims

1. a light emitting element including: a support substrate having a first surface and a second surface opposite to the first surface; and a first light emitting section and a second light emitting section disposed on the second surface of the support substrate, each of the first light emitting section and the second light emitting section including a semiconductor laminate having a first semiconductor layer, a light emitting layer, and a second semiconductor layer in that order, the first light emitting section and the second light emitting section being disposed adjacent to each other; a wavelength conversion member disposed on a first surface of the support substrate, the wavelength conversion member including a phosphor that converts the wavelength of the first light emitted from the first light emitter and the second light emitted from the second light emitter into a third light; a light adjusting member that is disposed on a surface of the wavelength converting member opposite to the surface on the supporting substrate side and overlaps one of the first light emitting unit and the second light emitting unit in a plan view; A light emitting device including a covering member that covers the light emitting element and a side surface of the wavelength conversion member, The light-emitting element is a light-emitting device in which, when the light-emitting device is emitting light, the emission intensity of the first light at the emission peak wavelength of the second light is smaller than the emission intensity of the second light at the emission peak wavelength of the second light, and the luminance of the first light-emitting section side and the luminance of the second light-emitting section side on the light-emitting surface of the light-emitting device are different.

2. The light emitting device according to claim 1 , wherein the wavelength conversion member comprises a wavelength conversion layer containing the phosphor, and a light-transmitting member supporting the wavelength conversion layer.

3. an emission peak wavelength of the first light is longer than an emission peak wavelength of the second light; the light adjusting member reflects the third light and transmits the first light, The light emitting device according to claim 1 , wherein the light adjustment member is disposed at a position overlapping with the first light emitting portion in a plan view.

4. an emission peak wavelength of the first light is longer than an emission peak wavelength of the second light; the light adjusting member reflects the second light and transmits the third light, The light emitting device according to claim 1 , wherein the light adjustment member is disposed at a position overlapping the second light emitting portion in a plan view.

5. 3. The light emitting device according to claim 1, wherein the first light emitting section and the second light emitting section have different current densities when emitting light.

6. The light emitting device according to claim 5 , wherein the first light emitting portion and the second light emitting portion have the same area in a plan view.

7. The light emitting device according to claim 5 , wherein the first light emitting portion and the second light emitting portion have different areas in a plan view.

8. 3. The light emitting device according to claim 1, wherein the light adjustment member is arranged to overlap one of the first light emitting section and the second light emitting section in a planar view, and extends to a position overlapping a portion of the other of the first light emitting section and the second light emitting section.

9. The light emitting device according to claim 1 , wherein the light adjusting member is a dielectric multilayer film.

10. 3 . The light emitting device according to claim 1 , wherein when the emission intensity of the second light is 100, the emission intensity of the first light is 10 or more and 70 or less.

11. 3. The light emitting device according to claim 1, wherein the first light and the second light have emission peak wavelengths of 420 nm or more and 460 nm or less, and the third light has an emission peak wavelength of 500 nm or more and 600 nm or less during emission.

12. 3. The light emitting device according to claim 1, wherein a difference between an emission peak wavelength of the first light and an emission peak wavelength of the second light during emission is 0.1 nm or more and 15 nm or less.

13. a wiring substrate on which the light emitting element is disposed, The light emitting device according to claim 6 , wherein the wiring board includes wiring capable of driving the first light emitting portion and the second light emitting portion individually.

14. a wiring substrate on which the light emitting element is disposed, The light emitting device according to claim 7 , wherein the wiring board includes wiring that connects the first light emitting portion and the second light emitting portion in series.

15. A step of preparing a light emitting element including: a support substrate having a first surface and a second surface opposite to the first surface; and a first light emitting portion and a second light emitting portion disposed adjacent to each other on the second surface of the support substrate, the first light emitting portion and the second light emitting portion each including a semiconductor laminate having a first semiconductor layer, a light emitting layer, and a second semiconductor layer in that order; A step of preparing a wavelength conversion member having a first surface and a second surface opposite to the first surface, the wavelength conversion member including a phosphor that converts the wavelength of a first light emitted from the first light emitter and a second light emitted from the second light emitter into a third light, and a light adjustment member disposed on the first surface of the wavelength conversion member; a step of disposing the wavelength conversion member on which the light adjustment member is disposed such that a second surface of the wavelength conversion member faces a first surface of the support substrate; and arranging a covering member that covers the light emitting element and a side surface of the wavelength conversion member, The step of arranging the wavelength conversion member includes arranging the light adjustment member at a position overlapping with either the first light emitting unit or the second light emitting unit in a plan view; A method for manufacturing a light emitting device in which the luminance of the first light emitting section side and the luminance of the second light emitting section side on a light emitting surface of the light emitting device are different.

16. the wavelength conversion member includes a wavelength conversion layer including the phosphor and a light-transmitting member supporting the wavelength conversion layer, The method for manufacturing a light emitting device according to claim 15 , wherein the step of arranging the wavelength conversion member comprises arranging the wavelength conversion member such that a surface of the wavelength conversion layer is located on a first surface side of the support substrate.

17. the light adjusting member reflects the third light and transmits the first light, 17. The method for manufacturing a light emitting device according to claim 15, wherein the step of arranging the wavelength conversion member comprises arranging the light adjustment member at a position overlapping the first light emitting portion in a plan view.

18. the light adjusting member reflects the second light and transmits the third light, 17. The method for manufacturing a light emitting device according to claim 15, wherein the step of arranging the wavelength conversion member comprises arranging the light adjustment member at a position overlapping the second light emitting portion in a plan view.

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