Light-emitting device

Abstract

To provide a light-emitting device including a plurality of light-emitting elements, in which the luminance difference between the light-emitting element in a lighting state and the light-emitting element in a non-lighting state is increased.SOLUTION: A light-emitting device includes a substrate, a plurality of light-emitting elements disposed on an upper surface of the substrate and being able to be driven individually, a wavelength conversion unit that covers an upper surface and a side surface of each light-emitting element, and a first light-blocking unit and a second light-blocking unit existing on a lower surface side of each light-emitting element and a lower surface side of the wavelength conversion unit. Between the adjacent light-emitting elements, a groove is provided in the wavelength conversion unit and the first light-blocking unit, and the second light-blocking unit is provided inside the groove. In one cross-sectional view, the second light-blocking unit is wider as being separated from the substrate and is exposed to an upper surface of the wavelength conversion unit.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a light emitting device. [Background technology]

[0002] A light emitting device is known that includes a substrate, a light emitting element held on the substrate, a first resin encapsulant that covers the light emitting element, and a second resin encapsulant formed on the first resin encapsulant, wherein the first resin encapsulant contains a light reflecting material, and the second resin encapsulant converts a portion of a first light emitted by the light emitting element into a second light having a different wavelength and mixes the first light and the second light. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2013 / 011628 issue Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to increase the difference in luminance between a light-emitting element that is on and a light-emitting element that is off in a light-emitting device having a plurality of light-emitting elements. [Means for solving the problem]

[0005] A light-emitting device according to one embodiment of the present disclosure comprises a substrate, a plurality of individually drivable light-emitting elements arranged on an upper surface of the substrate, a wavelength conversion unit covering the upper and side surfaces of each of the plurality of light-emitting elements, a first light-shielding unit located on the lower surface side of each of the plurality of light-emitting elements and the lower surface side of the wavelength conversion unit, and a second light-shielding unit, wherein grooves are provided in the wavelength conversion unit and the first light-shielding unit between adjacent light-emitting elements, and the second light-shielding unit is provided inside the groove, and in a cross-sectional view, the width of the second light-shielding unit increases with increasing distance from the substrate and is exposed on the upper surface of the wavelength conversion unit. [Effects of the Invention]

[0006] According to an embodiment of the present disclosure, in a light emitting device having a plurality of light emitting elements, it is possible to increase the difference in luminance between the light emitting elements that are lit and the light emitting elements that are turned off. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a perspective view schematically illustrating a light emitting device according to an embodiment of the present invention. [Figure 2] 1 is a perspective view schematically illustrating a light emitting device according to an embodiment of the present invention, with part of the configuration thereof omitted. [Figure 3] FIG. 1 is a top view schematically illustrating a light-emitting device according to an embodiment of the present invention. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Figure 5] 5 is a partially enlarged view of the light emitting element and its vicinity in FIG. 4. [Figure 6A] 5A to 5C are partial cross-sectional views illustrating a manufacturing process of the light emitting device according to the embodiment. [Figure 6B] 5A to 5C are partial cross-sectional views illustrating a manufacturing process of the light emitting device according to the embodiment. [Figure 6C] 5A to 5C are partial cross-sectional views illustrating a manufacturing process of the light emitting device according to the embodiment. [Figure 6D] 5A to 5C are partial cross-sectional views illustrating a manufacturing process of the light emitting device according to the embodiment. [Figure 6E] 5A to 5C are partial cross-sectional views illustrating a manufacturing process of the light emitting device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] A light-emitting device according to the present disclosure (hereinafter, sometimes referred to as a "light-emitting device according to an embodiment") will be described below with reference to the drawings. In the following description, terms indicating specific directions or positions (e.g., "upper," "lower," and other terms including these terms) will be used as necessary. However, the use of these terms is intended to facilitate understanding of the invention with reference to the drawings, and the meaning of these terms does not limit the technical scope of the present disclosure. Furthermore, parts that appear with the same reference numerals in multiple drawings indicate the same or equivalent parts or components.

[0009] Furthermore, the embodiments shown below are intended to exemplify light-emitting devices and the like that embody the technical concepts of the present invention, and are not intended to limit the present invention thereto. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are intended for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, the content described in one embodiment may also be applicable to other embodiments and modified examples. Furthermore, the size and positional relationships of components shown in the drawings may be exaggerated for clarity. Furthermore, to avoid overly complex drawings, schematic diagrams may be used in which some elements are omitted, or end views may be used as cross-sectional views that show only the cut surface.

[0010] <Embodiment> The light emitting device according to the present disclosure comprises a substrate, a plurality of individually drivable light emitting elements arranged on the upper surface of the substrate, a wavelength converting section covering the upper and side surfaces of each of the plurality of light emitting elements, a first shading section located on the lower surface side of each of the plurality of light emitting elements and the lower surface side of the wavelength converting section, and a second shading section, wherein grooves are provided in the wavelength converting section and the first shading section between adjacent light emitting elements, and the second shading section is provided inside the groove, and in a cross-sectional view, the width of the second shading section increases with increasing distance from the substrate and is exposed on the upper surface of the wavelength converting section.

[0011] [Light-emitting device 1] As an example of a light emitting device according to the present disclosure, a light emitting device 1 will be described. FIG. 1 is a perspective view schematically showing the light emitting device according to this embodiment. FIG. 2 is a perspective view schematically showing the light emitting device according to this embodiment with part of its configuration omitted. FIG. 3 is a top view schematically showing the light emitting device according to this embodiment. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. FIG. 5 is a partially enlarged view of the light emitting element of FIG. 4 and its vicinity.

[0012] In each drawing, for reference, mutually orthogonal X-, Y-, and Z-axes are shown as necessary. The direction parallel to the X-axis is called the X-direction, the direction parallel to the Y-axis is called the Y-direction, and the direction parallel to the Z-axis is called the Z-direction. In the X-direction, the direction in which the arrow points is called the +X-direction, and the direction opposite the +X-direction is called the -X-direction. In the Y-direction, the direction in which the arrow points is called the +Y-direction, and the direction opposite the +Y-direction is called the -Y-direction. In the Z-direction, the direction in which the arrow points is called the +Z-direction, and the direction opposite the +Z-direction is called the -Z-direction. However, these do not limit the orientation of the light-emitting device when in use, and the orientation of the light-emitting device is arbitrary. Viewing an object from the +Z-direction toward the -Z-direction is called top view.

[0013] As illustrated in FIGS. 1 to 5, the light emitting device 1 includes a substrate 10, a plurality of light emitting elements 30, a wavelength converting section 40, a first light-shielding section 50, and a second light-shielding section 60. The substrate 10 includes a substrate 10, a plurality of light emitting elements 30, a wavelength converting section 40, a first light-shielding section 50, and a second light-shielding section 60.

[0014] The plurality of light-emitting elements 30 are arranged on the upper surface 10a of the substrate 10. The plurality of light-emitting elements 30 can be arranged, for example, in a matrix when viewed from above. The plurality of light-emitting elements 30 can be driven individually. For example, the plurality of light-emitting elements 30 may be driven individually by using the substrate 10 as a semiconductor integrated circuit substrate such as an ASIC (Application Specific Integrated Circuit), or may be driven individually by an electric circuit provided outside the light-emitting device 1.

[0015] The wavelength conversion section 40 covers the top and side surfaces of each of the multiple light-emitting elements 30. The wavelength conversion section 40 converts light incident from the light-emitting elements 30 into light of a different wavelength and emits the converted light. The wavelength conversion section 40 may emit a portion of the incident light without converting it into light of a different wavelength, or may convert all of the incident light into light of a different wavelength and emit the converted light. The thickness from the top surface of the light-emitting elements 30 to the top surface of the wavelength conversion section 40 may be uniform or may vary for each light-emitting element 30.

[0016] The first light-shielding portion 50 is located on the lower surface side of each of the plurality of light-emitting elements 30 and the lower surface side of the wavelength converting portion 40. The upper surface of the first light-shielding portion 50 is in contact with, for example, the lower surface of each of the plurality of light-emitting elements 30 and the lower surface of the wavelength converting portion 40. The first light-shielding portion 50 covers the side surface of the electrode 35 of the light-emitting element 30. The first light-shielding portion 50 contains, for example, a light-reflecting member. The first light-shielding portion 50 may also contain a light-absorbing member.

[0017] A groove 45 is provided in the wavelength converting portion 40 and the first light-shielding portion 50 between adjacent light-emitting elements 30. In a cross-sectional view, the groove 45 becomes wider with increasing distance from the substrate 10, and opens to the upper surface of the wavelength converting portion 40.

[0018] The second light-shielding portion 60 is provided inside the groove 45. In a cross-sectional view, the width of the second light-shielding portion 60 increases with increasing distance from the substrate 10, and the second light-shielding portion 60 is exposed on the upper surface of the wavelength conversion portion 40. The second light-shielding portion 60 contains, for example, a light-absorbing material. The second light-shielding portion 60 may also contain a light-reflecting material. The second light-shielding portion 60 can be arranged, for example, to surround each of the multiple light-emitting elements 30 in a top view.

[0019] The light emitting device 1 may further include a package substrate 20, a wire 70, and a covering member 80. In the example of FIGS. 1 to 5, the substrate 10 is mounted on the upper surface 20a of the package substrate 20. On the upper surface 10a of the substrate 10, a first terminal 11 is arranged outside the area where the plurality of light emitting elements 30 are arranged. The package substrate 20 is larger than the substrate 10 in a top view. On the upper surface 20a of the package substrate 20, a second terminal 22 is arranged outside the area where the substrate 10 is mounted. The first terminal 11 of the substrate 10 is electrically connected to the second terminal 22 of the package substrate 20 by a wire 70. The first terminal 11, the second terminal 22, and the wire 70 are covered by a covering member 80 that is arranged on the outer periphery of the upper surface 10a of the substrate 10 and the outer periphery of the upper surface 20a of the package substrate 20. The wavelength conversion unit 40 may be located inside the covering member 80 in a top view.

[0020] For convenience of illustration, all of the wavelength converting portion 40 and the second light-shielding portion 60 and part of the covering member 80 are omitted in FIG. 2, and only the light-emitting element 30 and part of the wire 70 are visible.

[0021] In the light emitting device 1, since the plurality of light emitting elements 30 can be driven individually, there may be cases where one of adjacent light emitting elements 30 is lit and the other is extinguished. In this case, light from the lit light emitting element 30 attempts to travel toward the extinguished light emitting element 30, but the light attempting to travel toward the extinguished light emitting element 30 is reflected and / or absorbed by the second light-shielding portion 60 and does not reach the extinguished light emitting element 30. This makes it possible to increase the difference in luminance between the lit light emitting element 30 and the extinguished light emitting element 30. In other words, light can be emitted without causing substantial optical interference between adjacent light emitting elements 30.

[0022] Furthermore, in the light emitting device 1, in a cross-sectional view, the width of the second light-shielding portion 60 increases with increasing distance from the substrate 10, and the second light-shielding portion 60 is exposed on the upper surface of the wavelength conversion portion 40. Because the width of the second light-shielding portion 60 is greatest at the upper surface of the wavelength conversion portion 40, light blocking is improved and the difference in luminance between the lit light emitting element 30 and the extinguished light emitting element 30 can be further increased. The upper surface of the second light-shielding portion 60 preferably protrudes from the upper surface of the wavelength conversion portion 40. This allows light emitted from the wavelength conversion portion 40 to be reflected and / or absorbed toward the adjacent light emitting element 30, further improving light blocking and further increasing the difference in luminance between the lit light emitting element 30 and the extinguished light emitting element 30.

[0023] Furthermore, in the light emitting device 1, the wavelength converting section 40 covers not only the top surface but also the side surfaces of each of the multiple light emitting elements 30. This allows light emitted from the side surfaces of each light emitting element 30 to propagate to the top surface of the wavelength converting section 40, thereby increasing the light extraction efficiency and improving the brightness of the light emitting device 1. The top surface of the wavelength converting section 40 is preferably roughened. This increases the emission area from the wavelength converting section 40, thereby further improving the brightness of the light emitting device 1. When the top surface of the wavelength converting section 40 is roughened, the surface roughness may be, for example, 1 μm or more and 4 μm or less in terms of arithmetic mean height Sa. The arithmetic mean height Sa can be calculated, for example, by measuring the height from the mean plane of the surface for which the arithmetic mean height Sa is to be calculated at multiple points using a VK-X200 (manufactured by KEYENCE Corporation) and averaging the absolute values ​​of the measured heights.

[0024] Furthermore, in the light emitting device 1, when the first light-shielding portion 50 contains a light-reflecting member, the light emitted from the side surface of the light emitting element 30 and directed downward, and the light emitted from the bottom surface of the light emitting element 30, are reflected upward by the first light-shielding portion 50. This allows the brightness of the light emitting device 1 to be improved.

[0025] Furthermore, in the light-emitting device 1, the second light-shielding portion 60 is provided inside the grooves 45 provided in the wavelength conversion portion 40 and the first light-shielding portion 50, and therefore the second light-shielding portion 60 is located on the outer periphery of the interface between the wavelength conversion portion 40 and the first light-shielding portion 50. This makes it possible to suppress light leakage from the interface between the wavelength conversion portion 40 and the first light-shielding portion 50. Furthermore, compared to when the second light-shielding portion 60 is provided inside the grooves 45 provided only in the wavelength conversion portion 40, the contact area between the second light-shielding portion 60 and surrounding components is increased, thereby improving the adhesion between the second light-shielding portion 60 and the wavelength conversion portion 40 and the first light-shielding portion 50. The surfaces of the wavelength conversion portion 40 and the first light-shielding portion 50 that define the grooves 45 are preferably rough. This increases the contact area between the second light-shielding portion 60 and surrounding components, thereby further improving the adhesion between the second light-shielding portion 60 and the wavelength conversion portion 40 and the first light-shielding portion 50. When the surfaces of the wavelength converting portion 40 and the first light-shielding portion 50 that define the grooves 45 are rough, the surface roughness can be, for example, 1 μm or more and 4 μm or less in terms of arithmetic mean height Sa.

[0026] Each component of the light emitting device 1 will be described below.

[0027] (Substrate 10) The substrate 10 includes a flat support member and wiring arranged on the upper surface of the support member. The substrate 10 has an element mounting region 10r on its upper surface 10a where a plurality of light-emitting elements 30 are mounted, and wiring is arranged in the element mounting region 10r. The substrate 10 has a plurality of first terminals 11 arranged on the upper surface 10a outside the element mounting region 10r, and the first terminals 11 are electrically connected to the wiring arranged in the element mounting region 10r.

[0028] In top view, the substrate 10 and the element mounting region 10r may be, for example, a rectangle having long and short sides. For example, a plurality of light-emitting elements 30 are mounted in a matrix in the element mounting region 10r. The light-emitting elements 30 are electrically connected to one of the first terminals 11. The light-emitting elements 30 may be connected in series or parallel to the first terminals 11 in groups of a predetermined number. For example, the element mounting region 10r may have a long side length of 8 mm or more and 18 mm or less, and a short side length of 2 mm or more and 6 mm or less.

[0029] Each of the first terminals 11 has, for example, a substantially circular, elliptical, or rectangular shape. The first terminals 11 are spaced apart from one another and arranged in a row along opposing long sides of the rectangular element mounting region 10r on the upper surface 10a of the substrate 10, sandwiching the element mounting region 10r. The interval between adjacent first terminals 11 may or may not be constant. The interval between adjacent first terminals 11 may be, for example, 20 μm or more and 100 μm or less. One end of a wire 70 is connected to the first terminal 11.

[0030] The substrate 10 is, for example, a semiconductor substrate such as silicon. On the upper surface 10a of the substrate 10, areas where no wiring is arranged are covered with, for example, an insulating film. Wiring may also be arranged inside or on the lower surface of the support member. For example, the substrate 10 can be an integrated circuit substrate on which circuits for individually driving and controlling the plurality of light-emitting elements 30 are integrated.

[0031] Examples of materials for the first terminal 11 and the wiring include metals such as Cu, Ag, Au, Al, Pt, Ti, W, Pd, Fe, and Ni, and / or alloys containing at least these metals.

[0032] (Package substrate 20) The package substrate 20 includes a flat substrate and wiring arranged at least on the upper surface side of the substrate. The package substrate 20 has a substrate mounting area 20r on its upper surface 20a for mounting the substrate 10, and further includes second terminals 22 on the upper surface 20a outside the substrate mounting area 20r. The substrate mounting area 20r is an area on which the substrate 10 is mounted. The substrate mounting area 20r is set as an area having approximately the same area as the shape of the substrate 10 when viewed from above. If the substrate 10 is rectangular when viewed from above, the substrate mounting area 20r can also be rectangular. Here, "approximately the same" is intended to include within an allowable range errors caused by material tolerances and mounting tolerances.

[0033] Each second terminal 22 has, for example, a substantially circular, elliptical, or rectangular shape. The second terminals 22 are spaced apart from one another on the upper surface 20a of the package substrate 20 and arranged in a row along opposing long sides of the rectangle, sandwiching the substrate mounting region 20r. The interval between adjacent second terminals 22 may or may not be constant. The interval between adjacent second terminals 22 may be, for example, 20 μm or more and 100 μm or less. The other end of the wire 70 is connected to the second terminal 22.

[0034] The base material constituting the package substrate 20 is preferably a material with high heat dissipation properties, and more preferably a material with high light-blocking properties and base material strength. Specific examples include metals such as Al and Cu; ceramics such as aluminum oxide, aluminum nitride, silicon nitride, and mullite; resins such as phenolic resin, epoxy resin, polyimide resin, BT resin (bismaleimide triazine resin), and polyphthalamide (PPA); and composite materials composed of resin and metal or ceramic (e.g., an inlay substrate in which a metal member is embedded in a resin). The base material may be flat, or may have a recess on its upper surface. In this case, the package substrate 20 has a recess whose bottom serves as a substrate mounting area 20r, and the substrate 10 can be mounted in the recess.

[0035] The package substrate 20 may include wiring for mounting the substrate 10 on the surface of the substrate mounting area 20r.

[0036] (light-emitting element) The light-emitting element 30 may be, for example, a square with a side measuring 40 μm to 100 μm when viewed from above. The light-emitting element 30 has positive and negative electrodes 35 on the same side, and is flip-chip mounted on the substrate 10 with the side having the electrodes 35 facing downward. In this case, the upper surface opposite to the surface on which the electrodes 35 are arranged is the main light extraction surface of the light-emitting element 30.

[0037] In the light emitting device 1, the light emitting elements 30 are mounted on the substrate 10 in a row and column direction, aligned at predetermined intervals. The size and number of the light emitting elements 30 to be used can be selected appropriately depending on the type of light emitting device to be obtained. In particular, it is preferable to mount a larger number of smaller light emitting elements 30 at a higher density. This makes it possible to control the illumination range of the light emitted from the light emitting device 1 with a larger number of divisions. Such a light emitting device 1 can be used as a light source for a high-resolution lighting system. For example, the number of light emitting elements 30 provided in the light emitting device 1 can be between 1,000 and 100,000.

[0038] The light-emitting element 30 is, for example, a light-emitting diode. The light-emitting element 30 includes a semiconductor structure. The semiconductor structure includes an n-side semiconductor layer, a p-side semiconductor layer, and an active layer sandwiched between the n-side semiconductor layer and the p-side semiconductor layer. The active layer may have a single quantum well (SQW) structure or a multiple quantum well (MQW) structure including multiple well layers. The active layer is configured to be able to emit, for example, visible light or ultraviolet light.

[0039] The semiconductor structure may include multiple light-emitting sections, each including an n-side semiconductor layer, an active layer, and a p-side semiconductor layer. When the semiconductor structure includes multiple light-emitting sections, each light-emitting section may include well layers with different emission peak wavelengths or well layers with the same emission peak wavelength. The same emission peak wavelength also includes cases where the emission peak wavelengths vary by a few nanometers. The combination of emission peak wavelengths of the multiple light-emitting sections can be appropriately selected. For example, when the semiconductor structure includes two light-emitting sections, the combination of light emitted by each light-emitting section may be blue light with blue light, green light with green light, ultraviolet light with ultraviolet light, blue light with green light, blue light with ultraviolet light, or green light with ultraviolet light. For example, when the semiconductor structure includes three light-emitting sections, the combination of light emitted by each light-emitting section may be blue light, green light, and red light. Each light-emitting section may include one or more well layers with emission peak wavelengths different from those of the other well layers.

[0040] As the light emitting element 30, for example, a light emitting element capable of emitting blue light (light with a wavelength of 430 to 490 nm) can be used. However, the light emitting color of the light emitting element 30 can be selected from any wavelength depending on the application. For example, as a light emitting element for blue (light with a wavelength of 430 to 490 nm) or green (light with a wavelength of 495 to 565 nm), a nitride-based semiconductor (In x Al y Ga 1-x-y N (0≦x, 0≦y, x+y≦1), GaP, etc. can be used. As a red light emitting element (light with a wavelength of 610 to 700 nm), GaAlAs, AlInGaP, etc. can be used in addition to nitride-based semiconductor elements.

[0041] The light-emitting element 30 is bonded to wiring arranged in the element mounting region 10r of the substrate 10 by a conductive bonding member. When flip-chip mounting the light-emitting element 30 on the substrate 10, bumps made of a metal material such as Au, Ag, Cu, or Al can be used as the bonding member. Alternatively, solder such as an AuSn-based alloy or Sn-based lead-free solder can be used as the bonding member. Alternatively, a conductive adhesive made of resin containing conductive particles such as metal can be used as the bonding member. A plating method can be used to bond the light-emitting element 30 to the substrate 10. Examples of plating materials include Cu and Au. Alternatively, the electrodes 35 of the light-emitting element 30 and the wiring of the substrate 10 can be directly connected to each other without a bonding member.

[0042] (wavelength conversion part) The wavelength converting portion 40 includes, for example, a resin and a phosphor. Examples of the resin include known translucent resins such as silicone resin and epoxy resin. Among them, silicone resin (specifically, translucent resins such as phenyl silicone resin and dimethyl silicone resin) is preferred for its excellent reliability.

[0043] The phosphor is an yttrium-aluminum-garnet phosphor (e.g., (Y,Gd)3(Al,Ga)5O 12 :Ce), lutetium aluminum garnet phosphors (e.g., Lu3(Al,Ga)5O 12 :Ce), terbium aluminum garnet phosphors (e.g., Tb3(Al,Ga)5O 12 :Ce), CCA-based phosphors (e.g., Ca 10 (PO4)6Cl2:Eu), SAE-based phosphors (e.g., Sr4Al 14 O 25 :Eu), chlorosilicate phosphors (e.g., Ca8MgSiO 16 Cl2:Eu), silicate-based phosphors (e.g., (Ba,Sr,Ca,Mg)2SiO4:Eu), β-sialon-based phosphors (e.g., (Si,Al)3(O,N)4:Eu) or α-sialon-based phosphors (e.g., Ca(Si,Al)12 (O,N) 16 Oxynitride phosphors such as (Eu), LSN phosphors (e.g., (La,Y)3Si6N 11 :Ce), BSESN phosphors (e.g., (Ba,Sr)2Si5N8:Eu), SLA phosphors (e.g., SrLiAl3N4:Eu), CASN phosphors (e.g., CaAlSiN3:Eu) or SCASN phosphors (e.g., (Sr,Ca)AlSiN3:Eu), nitride phosphors such as KSF phosphors (e.g., K2SiF6:Mn), KSAF phosphors (e.g., K2(Si 1-x Al x )F 6-x :Mn where 0 < x < 1. ) or fluoride phosphors such as MGF phosphors (e.g., 3.5MgO·0.5MgF2·GeO2:Mn), quantum dots having a perovskite structure (e.g., (Cs,FA,MA)(Pb,Sn)(F,Cl,Br,I)3 where FA and MA represent formamidinium and methylammonium, respectively), II-VI group quantum dots (e.g., CdSe), III-V group quantum dots (e.g., InP), or quantum dots having a chalcopyrite structure (e.g., (Ag,Cu)(In,Ga)(S,Se)2) can be used.

[0044] When the light-emitting element 30 can emit blue light, the wavelength conversion unit 40 can contain, for example, a phosphor that can be excited by blue light and emit yellow light. In this case, examples of the phosphor contained in the wavelength conversion unit 40 include yttrium aluminum garnet-based phosphors (e.g., (Y,Gd)3(Al,Ga)5O 12 :Ce). According to such a configuration, white light can be obtained by mixing the blue light that has passed through the wavelength conversion unit 40 and the yellow light emitted by the wavelength conversion unit 40.

[0045] (First light-shielding portion) The first light-shielding part 50 is preferably made of a soft resin with relatively low elasticity and excellent shape conformability. Resin materials with good transparency and insulating properties, such as thermosetting resins such as epoxy resin and silicone resin, are preferably used as the material for the first light-shielding part 50. Furthermore, the first light-shielding part 50 is preferably made of a resin containing a light-reflecting material in its base resin. Suitable light-reflecting materials include titanium oxide, aluminum oxide, zinc oxide, barium carbonate, barium sulfate, boron nitride, aluminum nitride, and glass filler. The first light-shielding part 50 may also contain a light-absorbing material. Suitable light-absorbing materials include pigments, carbon black, titanium black, and graphite.

[0046] (Second light-shielding part) The second light-shielding part 60 is preferably made of a soft resin with relatively low elasticity and excellent shape-following ability, similar to the first light-shielding part 50. The second light-shielding part 60 may be made of the same material as the material used for the first light-shielding part 50. The second light-shielding part 60 is preferably made of a resin containing the above-mentioned light-absorbing material in its base resin. The second light-shielding part 60 may also contain the above-mentioned light-reflecting material.

[0047] When the upper surface of the second light-shielding portion 60 protrudes from the upper surface of the wavelength converting portion 40, the protrusion can be shaped so that, in a cross-sectional view, the height is highest in the center and gradually decreases toward the periphery. In a cross-sectional view, the ratio of the width of the protrusion at the position of the upper surface of the wavelength converting portion 40 to the height from the upper surface of the wavelength converting portion 40 to the top of the protrusion is preferably 1:1 or less. With such a shape, the second light-shielding portion 60 is less likely to spread over the upper surface of the wavelength converting portion 40. The width of the protrusion at the position of the upper surface of the wavelength converting portion 40 can be, for example, approximately the same as the spacing between adjacent light-emitting elements 30. The spacing between adjacent light-emitting elements 30 is, for example, approximately 5 to 10 μm.

[0048] (wire) The wires 70 can be made of metals such as Au, Ag, Cu, Pt, and Al and / or alloys containing at least these metals. Au, which has excellent thermal resistance, is particularly preferred. The diameter of the wires 70 can be, for example, 15 μm to 50 μm. The wires 70 can be arranged across the long sides of the substantially rectangular substrate 10 in a top view, for example, so as to be substantially perpendicular to the long sides. Furthermore, among the multiple wires 70 arranged in a row along the long sides of the substrate 10, the wires 70 located in the center of the row can be arranged so as to be substantially perpendicular to the long sides of the substrate 10 in a top view, as described above, while the wires 70 located at the ends of the row can be arranged diagonally relative to the long sides of the substrate 10 in a top view. The interval at which the wires 70 are aligned can be 20 μm to 100 μm.

[0049] (Covering material) The covering member 80 is a light-shielding member that covers the wires 70 outside the element mounting region 10r. Note that, as an example, the covering member 80 is arranged in a frame shape in a top view so as to cover the wires 70 and surround the element mounting region 10r.

[0050] The covering member 80 is disposed at a distance from the light emitting element 30 in a top view. The covering member 80 is preferably disposed so that its height (i.e., the distance from the upper surface 20a of the package substrate 20 to the upper surface of the covering member 80) is greatest directly above the top of the wire 70. In other words, the covering member 80 is preferably disposed so that its top overlaps the top of the wire 70.

[0051] The covering member 80 may be, for example, a resin containing a filler with light-blocking properties. Examples of resins that can be used as the base material include silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, and acrylic resin. Examples of fillers with light-blocking properties include the light-reflecting or light-absorbing materials that may be contained in the first light-shielding section 50 described above. The exterior color of the covering member 80 may be white, which has excellent light reflectivity, black, which has excellent light absorption, or gray, which has both light reflectivity and light absorption properties. The covering member 80 may also be formed by laminating multiple resin layers. In particular, in consideration of deterioration of the resin due to light absorption, it is preferable that the covering member 80 use a white resin with light reflectivity on at least the outermost surface.

[0052] The light emitting device 1 having the above configuration can be used, for example, as a light source for a vehicle headlight. For example, it can be used as a light source that can select an illumination area and irradiate it with light, such as a headlight with an ADB (Adaptive Driving Beam) function. In this case, since the light emitting device 1 can increase the difference in luminance between the light emitting element that is turned on and the light emitting element that is turned off, it is possible to realize a headlight with good contrast using a single light source.

[0053] [Method of manufacturing the light emitting device 1] Hereinafter, each manufacturing step of the manufacturing method of the light emitting device according to the embodiment will be described with reference to the drawings.

[0054] 6A to 6E are partial cross-sectional views illustrating the manufacturing process of the light emitting device according to this embodiment.

[0055] (Step of mounting the light emitting element 30 on the substrate 10 and arranging the first light blocking portion 50) First, as shown in FIG. 6A , a plurality of light-emitting elements 30 are mounted on a substrate 10, and a first light-shielding portion 50 is disposed on the underside of the light-emitting elements 30. Specifically, a substrate 10 is prepared, which has an element-mounting region 10r and a first terminal 11 disposed outside the element-mounting region 10r on its upper surface 10a. The substrate 10 can be prepared, for example, by preparing a flat support member made of silicon or the like, and forming wiring and the first terminal 11 by plating, sputtering, vapor deposition, or the like. A plurality of light-emitting elements 30 are also prepared. The light-emitting elements 30 can be prepared by some or all of multiple processes, such as forming a semiconductor stack and forming electrodes. Note that in the description of the manufacturing method, "preparing" components does not necessarily mean manufacturing the components, but also includes acquiring the components, such as purchasing or receiving the components.

[0056] Next, the light-emitting element 30 is placed in the element mounting region 10r of the substrate 10. The light-emitting element 30 can be mounted in the element mounting region 10r on the upper surface 10a of the substrate 10 by flip-chip mounting or the like. After the light-emitting element 30 is placed in the element mounting region 10r of the substrate 10, a first light-shielding portion 50 is placed between the lower surface of the light-emitting element 30 and the upper surface 10a of the substrate 10. For example, after the light-emitting element 30 is placed on the substrate 10, a mask is placed to cover the first terminal 11 and expose the element mounting region 10r. Then, a first light-shielding portion 50 made of uncured white resin or the like is placed in an area separated from the light-emitting element 30, and the white resin or the like is allowed to flow toward the lower surface of the light-emitting element 30 and harden. After hardening, the mask is removed, and the first terminal 11 is exposed from the first light-shielding portion 50.

[0057] (Step of placing the wavelength conversion section 40) Next, as shown in FIG. 6B , a wavelength conversion unit 40 covering the upper and side surfaces of the light-emitting element 30 is disposed on the first light-shielding unit 50 disposed on the upper surface 10a of the substrate 10. The wavelength conversion unit 40 is disposed so as to expose the first terminal 11. Specifically, for example, a sheet-shaped member having a predetermined size is prepared as the wavelength conversion unit 40 and disposed on the light-emitting element 30. The wavelength conversion unit 40 may be fixed to the light-emitting element 30 via a translucent bonding member such as resin, or may be fixed without a bonding member by utilizing the tackiness of the wavelength conversion unit 40. Instead of disposing a sheet-shaped member on the light-emitting element 30, the wavelength conversion unit 40 may be applied to the light-emitting element 30 by spraying or the like. Alternatively, the wavelength conversion unit 40 may be formed by injection molding using a mold or the like, transfer molding, compression molding, or the like.

[0058] (Step of forming groove 45) Next, as shown in FIG. 6C , grooves 45 are formed in the wavelength conversion section 40 and the first light-shielding section 50 located between adjacent light-emitting elements 30. In a cross-sectional view, the grooves 45 become wider with increasing distance from the substrate 10 and open to the upper surface of the wavelength conversion section 40. Grooves 45 of this shape can be formed, for example, by irradiating the upper surface of the wavelength conversion section 40 with laser light. An excimer laser, for example, can be used to form the grooves 45. The spot diameter of the laser light on the upper surface of the wavelength conversion section 40 is, for example, 0.3 μm or more and 10 μm or less. Therefore, it is possible to form grooves 45 with a relatively narrow width. Note that, when forming relatively wide grooves 45, a mechanical method such as dicing may be used.

[0059] (Step of roughening the upper surface of the wavelength conversion portion 40) Next, as shown in FIG. 6D , a step of roughening the upper surface of the wavelength converting section 40 and the surfaces of the wavelength converting section 40 and first light-shielding section 50 that define the grooves 45 may be provided. Roughening can be achieved, for example, by spraying fine dry ice particles onto the target surface together with compressed air. Sandblasting can also be used to roughen the surface, but sandblasting can leave residual abrasives that can contaminate the surface of the wavelength converting section 40. In contrast, when dry ice is used, the fine dry ice particles evaporate and dissipate into the atmosphere, so no abrasives remain after use, reducing the risk of contamination of the surface of the wavelength converting section 40.

[0060] (Step of arranging the second light-shielding portion 60) Next, as shown in FIG. 6E, the second light-shielding portion 60 is placed inside the groove 45. In a cross-sectional view, the width of the second light-shielding portion 60 increases with increasing distance from the substrate 10, and the second light-shielding portion 60 is exposed on the upper surface of the wavelength conversion portion 40. The upper surface of the second light-shielding portion 60 may protrude from the upper surface of the wavelength conversion portion 40. The second light-shielding portion 60 can be placed inside the groove 45 by, for example, potting, dropping uncured resin, which will become the second light-shielding portion 60 when cured, into the groove 45 or its vicinity. Note that, The uncured resin dropped near the groove 45 penetrates into the interior of the groove 45 due to capillary action.

[0061] (Step of placing the substrate 10 on the package substrate 20) Next, a package substrate 20 is prepared, which has a substrate mounting area 20r on which the substrate 10 is mounted, and second terminals 22 located outside the substrate mounting area 20r, on its upper surface 20a. The package substrate 20 can be prepared, for example, by forming wiring such as Cu and the second terminals 22 on a flat support member made of metal, ceramic, or the like by plating, sputtering, vapor deposition, or the like. Next, the substrate 10 on which the light-emitting element 30 is mounted is placed on the substrate mounting area 20r of the package substrate 20. The substrate 10 and the package substrate 20 can be bonded together via a bonding member such as a sintered body containing Ag or a resin material.

[0062] (Process of connecting with wire 70) Next, the first terminal 11 of the substrate 10 and the second terminal 22 of the package substrate 20 are connected by the wire 70. For example, the wire 70 is first connected to the first terminal 11 of the substrate 10, and then connected to the second terminal 22 of the package substrate 20. By connecting the wire 70 in this order, the top of the wire 70 can be positioned closer to the first terminal 11. This allows the wire 70 to be positioned along the step between the substrate 10 and the package substrate 20. Therefore, in the step of arranging the covering member 80 described below, the amount of resin positioned below the wire 70 is reduced, and the risk of the wire 70 being broken due to thermal expansion of the covering member 80 can be reduced.

[0063] (Step of placing the covering member 80) Next, a covering member 80 that covers the first terminals 11, the second terminals 22, and the wires 70 is placed on the outer periphery of the upper surface 10a of the substrate 10 and on the outer periphery of the upper surface 20a of the package substrate 20. The covering member 80 can be placed, for example, by supplying uncured resin to a predetermined position using a dispenser or the like and then curing it. Note that the covering member 80 may be placed after the wavelength conversion section 40 is placed. Through the above steps, the light emitting device 1 is completed.

[0064] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0065] In addition to the above-described embodiments, the following supplementary notes are also disclosed. (Appendix 1) A substrate; a plurality of individually drivable light-emitting elements disposed on an upper surface of the substrate; a wavelength converting portion covering an upper surface and a side surface of each of the plurality of light emitting elements; a first light-shielding portion located on a lower surface side of each of the plurality of light-emitting elements and on a lower surface side of the wavelength converting portion; a second light-shielding portion, a groove is provided in the wavelength converting portion and the first light-shielding portion between adjacent light-emitting elements; the second light-shielding portion is provided inside the groove, A light emitting device, wherein, in a cross-sectional view, the second light-shielding portion has a width that increases with increasing distance from the substrate, and is exposed on an upper surface of the wavelength converting portion. (Appendix 2) 2. The light emitting device according to claim 1, wherein an upper surface of the second light shielding portion protrudes from an upper surface of the wavelength converting portion. (Appendix 3) 3. The light-emitting device according to claim 1, wherein the first light-shielding portion includes a light-reflecting material, and the second light-shielding portion includes a light-absorbing material. (Appendix 4) 4. The light emitting device according to claim 1, wherein the upper surface of the wavelength converting portion is a rough surface. (Appendix 5) 5. The light emitting device according to claim 1, wherein the surfaces of the wavelength converting portion and the first light blocking portion that define the groove are rough. (Appendix 6) the plurality of light-emitting elements are arranged in a matrix in top view, 6. The light emitting device according to claim 1, wherein the second light-shielding portion surrounds each of the plurality of light emitting elements in a top view. [Explanation of symbols]

[0066] 1. Light-emitting device 10 Substrate 10a Top 10r Element mounting area 11 1st terminal 20 Package substrate 20a top surface 20r Substrate placement area 22 2nd terminal 30 Light-emitting element 35 electrodes 40 Wavelength conversion unit 45 Groove 50 First light-shielding part 60 Second light-shielding part 70 wire 80 Covering material

Claims

1. A substrate; a plurality of individually drivable light-emitting elements disposed on an upper surface of the substrate; a wavelength converting portion covering an upper surface and a side surface of each of the plurality of light emitting elements; a first light-shielding portion located on a lower surface side of each of the plurality of light-emitting elements and on a lower surface side of the wavelength converting portion; a second light-shielding portion, a groove is provided in the wavelength converting portion and the first light-shielding portion between adjacent light-emitting elements; the second light-shielding portion is provided inside the groove, a second light-shielding portion that, in a cross-sectional view, increases in width with increasing distance from the substrate and is exposed on an upper surface of the wavelength converting portion;

2. The light emitting device according to claim 1 , wherein an upper surface of the second light blocking portion protrudes from an upper surface of the wavelength converting portion.

3. The light emitting device according to claim 1 , wherein the first light-shielding portion includes a light-reflecting material, and the second light-shielding portion includes a light-absorbing material.

4. The light emitting device according to claim 1 , wherein the upper surface of the wavelength converting portion is a rough surface.

5. The light emitting device according to claim 1 , wherein the surfaces of the wavelength converting portion and the first light blocking portion that define the groove are rough.

6. the plurality of light-emitting elements are arranged in a matrix in top view, The light emitting device according to claim 1 , wherein the second light blocking portion surrounds each of the plurality of light emitting elements in a top view.

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