Light-emitting device

Abstract

To provide a light-emitting device that can stably bond a plurality of light-emitting elements with a side surface covered with a covering member, to a substrate.SOLUTION: A light-emitting device 1 includes a plurality of light-emitting elements 2 including a semiconductor multilayer body 21 and positive and negative electrodes 22 disposed on a lower surface side of the semiconductor multilayer body 21, and a covering member 3 that covers collectively side surfaces 2b of the light-emitting elements 2. A lower surface of the covering member 3 includes one or more first convex parts 3a1 located lower than lower surfaces 22b of the positive and negative electrodes 22, and one or more second convex parts 3a2 located lower than the first convex parts 3a1. The one or more second convex parts 3a2 are disposed so as to include at least an apex forming a triangle surrounding a center C of the light-emitting device 1 in a top view.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] There is known a light emitting device having a light emitting element and a resin body that covers the side surface of the light emitting element in an annular shape. For example, Patent Document 1 discloses a light emitting device in which a plurality of light emitting elements whose side surfaces are covered with a resin body are mounted on a mounting board via a bonding member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP2019-121703A 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 capable of stably bonding a plurality of light emitting elements, the sides of which are covered with a covering member, to a substrate. [Means for solving the problem]

[0005] The present disclosure solves the above-mentioned problems, and one embodiment of the light-emitting device of the present disclosure is a light-emitting device comprising a semiconductor laminate, a plurality of light-emitting elements having positive and negative electrodes arranged on the underside of the semiconductor laminate, and a covering member that collectively covers the side surfaces of the plurality of light-emitting elements, wherein the underside of the covering member has one or more first convex portions located below the undersides of the positive and negative electrodes and one or more second convex portions located below the first convex portions, and the one or more second convex portions are arranged so as to include at least the vertices that form a triangle surrounding the center of the light-emitting device when viewed from above. Effect of the Invention

[0006] According to the light emitting device according to the above aspect of the present disclosure, a plurality of light emitting elements having side surfaces covered with a covering member can be stably joined to a substrate. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a top view diagrammatically illustrating an example of a light emitting device 1 according to an embodiment. [Diagram 2] 2 is a perspective view showing an example of a light emitting device 1 according to an embodiment including a cross section taken along line II-II shown in FIG. [Diagram 3] 3 is a cross-sectional view taken along line III-III shown in FIG. [Figure 4] FIG. 1 is a top view showing a schematic example of an arrangement of a plurality of light emitting devices 1 according to an embodiment. [Diagram 5] 1 is a cross-sectional view showing a schematic example of a light emitting device 1 according to an embodiment mounted on a substrate. [Figure 6] 4 is a flowchart showing an example of a method for manufacturing the light emitting device 1 according to the embodiment. [Figure 7A] 1 is a cross-sectional view illustrating a schematic diagram of a method for manufacturing the light-emitting device 1 according to the embodiment, showing an example of step S1 of preparing a light-transmitting member 4. FIG. [Figure 7B] 1 is a cross-sectional view showing a schematic diagram of a method for manufacturing the light-emitting device 1 according to the embodiment, illustrating an example of a step S2 of slitting the light-transmitting member 4. FIG. [Figure 7C] 1 is a cross-sectional view showing a schematic diagram of a method for manufacturing the light emitting device 1 according to the embodiment, illustrating an example of a step S3 of arranging the light emitting element 2. FIG. [Figure 7D] FIG. 2 is a cross-sectional view illustrating a schematic diagram of a method for manufacturing the light emitting device 1 according to the embodiment, showing an example of step S4 of arranging the covering member 3. [Figure 7E] 1 is a cross-sectional view that illustrates a schematic diagram of a method for manufacturing the light emitting device 1 according to the embodiment, showing an example of step S5 of grinding the covering member 3. FIG. [Figure 7F] FIG. 11 is a cross-sectional view that illustrates a schematic diagram of a method for manufacturing the light emitting device 1 according to the embodiment, showing an example of step S6 of forming the first convex portion 3a1 and the second convex portion 3a2. [Figure 7G]1 is a cross-sectional view that illustrates a schematic diagram of a method for manufacturing the light emitting device 1 according to the embodiment, showing an example of step S7 for forming the protective portion 22a. [Figure 7H] FIG. 2 is a cross-sectional view showing a schematic diagram of a method for manufacturing the light emitting device 1 according to the embodiment, illustrating an example of step S8 of forming a light emitting surface and dividing the device into individual pieces. [Figure 7I] 1 is a cross-sectional view showing a schematic diagram of a method for manufacturing the light emitting device 1 according to the embodiment, illustrating an example of a step S10 of mounting a substrate 6. FIG. [Figure 8] FIG. 11 is a top view diagrammatically illustrating an example of a light emitting device 1 according to another embodiment. [Figure 9] FIG. 11 is a top view diagrammatically illustrating another example of the light emitting device 1 according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. Note that the light emitting device 1 according to this embodiment is intended to embody the technical idea of ​​the present disclosure, and unless otherwise specified, the present disclosure is not limited to the following. The size and positional relationship of the components shown in each drawing may be appropriately exaggerated, and some of the components may be simplified or omitted.

[0009] In this embodiment, for convenience of explanation, an XYZ orthogonal coordinate system is adopted for explanation. Specifically, the thickness direction of the light emitting element 2 (details will be described later) provided in the light emitting device 1 is the "Z axis", and the two directions perpendicular to the thickness direction are the "X axis" and the "Y axis". On the Z axis, the direction in which the light from the light emitting device 1 mainly travels is the "upper", and the opposite direction is the "lower". However, the expressions "upper" and "lower" are also for convenience and are unrelated to the direction of gravity. In addition, the expression "top view" in this specification refers to a case where the view is viewed from above the Z axis to below. In addition, as a cross-sectional view, an end view showing only a cut surface may be shown.

[0010] (Light emitting device 1) Fig. 1 is a top view diagrammatically illustrating an example of a light emitting device 1 according to an embodiment. Fig. 2 is a perspective view including a cross section taken along line II-II in Fig. 1, illustrating an example of a light emitting device 1 according to an embodiment. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 1.

[0011] The light emitting device 1 according to this embodiment includes a semiconductor structure 21, a plurality of light emitting elements 2 each having positive and negative electrodes 22 arranged on the lower surface side of the semiconductor structure 21, and a covering member 3 for collectively covering the side surfaces 2b of the plurality of light emitting elements 2. In the light emitting device 1, the lower surface 3a of the covering member 3 has a first convex portion 3a1 located below the lower surface 22b of the positive and negative electrodes 22, and a second convex portion 3a2 located below the first convex portion 3a1. The second convex portion 3a2 is arranged so as to include at least vertices T1, T2, and T3 that form a triangle T surrounding the center C of the light emitting device 1 in a top view. Note that the "center" in this embodiment includes not only the center of the shape in a top view, but also the "centre of gravity," the "internal center," the "pericenter," the "orthocenter," and the "exocenter."

[0012] In the light emitting device 1, the second convex portion 3a2 is located below the light emitting element 2 and the first convex portion 3a1. The second convex portion 3a2 includes at least vertices T1, T2, and T3 that form a triangle T surrounding the center C of the light emitting device 1 in a top view. With this structure, when the light emitting device 1 is mounted on a substrate 6 described below, the second convex portion 3a2 can support the multiple light emitting elements 2 with respect to the substrate 6 in a state of being spaced apart from the substrate 6. Therefore, the light emitting device 1 can stably bond the multiple light emitting elements 2 to the substrate 6.

[0013] (Light emitting element 2) The light-emitting element 2 is, for example, an element that emits light of an arbitrary wavelength. The light-emitting element 2 mainly emits light from the top surface 2a. The light-emitting element 2 may emit light from the side surface 2b. The wavelengths of light emitted by the multiple light-emitting elements 2 may all be the same, or some or all of them may be different.

[0014] The light-emitting element 2 may be, for example, a light-emitting diode, a laser diode, or the like. The light-emitting element 2 has a semiconductor structure 21 and an electrode 22. In the light-emitting element 2 shown in FIG. 3, the electrode 22 is disposed below the semiconductor structure 21. The semiconductor structure 21 may include a support substrate and a semiconductor layer disposed on the support substrate. In this case, the support substrate, the semiconductor layer, and the electrode 22 are disposed in this order.

[0015] The semiconductor structure 21 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 semiconductor structure 21 includes multiple semiconductor layers made of nitride semiconductors. The nitride semiconductors are In x Al y Ga 1-x-y The term includes semiconductors of all compositions in which the composition ratios x and y in the chemical formula N (0≦x, 0≦y, x+y≦1) are changed within the respective ranges. The emission peak wavelength of the active layer can be appropriately selected depending on the purpose. The active layer is configured to be capable of emitting, for example, visible light or ultraviolet light.

[0016] The semiconductor structure 21 may include a plurality of light emitting sections including an n-side semiconductor layer, an active layer, and a p-side semiconductor layer. When the semiconductor structure 21 includes a plurality of light emitting sections, each light emitting section may include well layers having different emission peak wavelengths, or may include well layers having the same emission peak wavelength. The same emission peak wavelength includes a case where the emission peak wavelengths vary by about several nm. The combination of emission peak wavelengths of the plurality of light emitting sections may be appropriately selected. For example, when the semiconductor structure 21 includes two light emitting sections, the combination of light emitted by each light emitting section may be blue light and blue light, green light and green light, red light and red light, ultraviolet light and ultraviolet light, blue light and green light, blue light and red light, or green light and red light. For example, when the semiconductor structure 21 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 having emission peak wavelengths different from other well layers.

[0017] The light-emitting element 2 has positive and negative electrodes 22 on the same side of the semiconductor structure 21, and the positive and negative electrodes 22 are electrically connected to positive and negative wirings 61 via bonding members 7 described below. A protective portion 22a may be formed on a lower surface 22b of the electrode 22. The protective portion 22a may be formed by sputtering a metal film of titanium, gold, or the like. The light-emitting element 2 does not necessarily have to have the protective portion 22a.

[0018] The light-emitting element 2 of this embodiment is rectangular when viewed from above. The length of each side of the light-emitting element 2 when viewed from above is, for example, 100 μm or more and 3000 μm or less. The thickness of the light-emitting element 2 is, for example, 50 μm or more and 2000 μm or less. The shape of the light-emitting element 2 when viewed from above may be, for example, a polygon such as a triangle or a hexagon, or a circle, an ellipse, or the like.

[0019] (Covering material 3) The covering member 3 has a function of holding the plurality of light-emitting elements 2 in a predetermined arrangement. In addition, the covering member 3 preferably has a function of reflecting light emitted from the side surface 2b of the light-emitting element 2 and guiding the light upward to the light-emitting element 2. This can improve the efficiency of use of light emitted from the light-emitting element 2. The covering member 3 is disposed between the plurality of light-emitting elements 2 and in the entire peripheral region 1a of the plurality of light-emitting elements 2. This allows the covering member 3 to cover and hold the plurality of light-emitting elements 2 collectively. In addition, the covering member 3 exposes the upper surfaces 2a of the plurality of light-emitting elements 2. In other words, the light-emitting surface of the light-emitting element 2 is exposed. It is preferable that the covering member 3 further covers the semiconductor structure 21 of the light-emitting element 2 except for the lower surface 22b of the electrode 22. This allows the light emitted from the light-emitting element 2 to be efficiently extracted from the light-emitting surface. However, the covering member 3 exposes the lower surface 22b of the electrode 22 including the protective portion 22a.

[0020] The covering member 3 is a member having light reflectivity and / or light absorption. In particular, it is preferable that the covering member 3 has high light reflectivity. This allows light emitted from the side surface 2b of the light-emitting element 2 to be reflected and extracted from the upper surface 2a, resulting in a light-emitting device with excellent light extraction efficiency. Specifically, the covering member 3 preferably has a reflectance of 60% or more, and more preferably has a reflectance of 80% or more, for the light emitted from the light-emitting element 2.

[0021] The covering member 3 includes a resin base material and particles of a light-reflecting material contained in the resin. The resin base material of the covering member 3 is preferably a resin that is relatively soft and has a low elastic modulus. Examples of the resin include resins that include one or more of silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, acrylic resin, and fluororesin. Among them, it is preferable to use a silicone resin that is excellent in weather resistance and heat resistance, and it is more preferable to use a dimethyl silicone resin. Dimethyl silicone resin tends to be relatively softer and has a lower elastic modulus than phenyl silicone resin, so it is easily deformed by external stress, and in the manufacturing process described below, it is easy to form the first convex portion 3a1 and the second convex portion 3a2 on the lower surface of the covering member 3. Specifically, it is preferable to use a resin that has an elastic modulus of 10 MPa or less after curing for the covering member 3. Examples of the light-reflecting material include titanium oxide, aluminum oxide, silicon oxide, and zinc oxide. The average particle diameter of the light-reflecting material can be, for example, 0.05 μm or more and 30 μm or less. The covering member 3 may further include a light absorbing material such as a pigment or carbon black, a phosphor, and the like. In the covering member 3, particles of a light-reflective material are preferably dispersed in the resin.

[0022] As shown in FIG. 3, the lower surface 3a of the covering member 3 of this embodiment has a first convex portion 3a1 located below the lower surfaces 22b of the positive and negative electrodes 22, and a second convex portion 3a2 located below the first convex portion 3a1. The first convex portion 3a1 covers the space between the adjacent light-emitting elements 2 and the adjacent electrodes 22. Note that FIG. 3 shows a line connecting the lower surfaces 22b of the electrodes 22 as A. In addition, the second convex portion 3a2 of this embodiment is arranged in a frame shape that at least partially surrounds the light-emitting element 2 when viewed from above. By arranging the second convex portion 3a2 in a frame shape that at least partially surrounds the light-emitting element 2 when viewed from above, a plurality of light-emitting elements 2 that are grouped together as one light-emitting device can be stably joined to the substrate 6.

[0023] The first convex portion 3a1 in this embodiment is located below the lower surface 22b of the electrode 22 by the following length α. Here, the lengths α of the multiple first convex portions 3a1 observed in a cross-sectional view do not all need to be the same and may be different. The second convex portion 3a2 is located below the lower surface 22b of the electrode 22 by the following length β. The lengths β of the multiple second convex portions 3a2 observed in a cross-sectional view do not all need to be the same and may be different within an error range (±5 μm). α < 40μm β ≧ 40μm

[0024] The length β of the second protrusion 3a2 from the lower surface 22b of the electrode 22 can be set as follows. β ≧ 60μm

[0025] Furthermore, the covering member 3 of this embodiment may cover the side surface 4b of the light-transmitting member 4 described below. The upper surface 3d of the covering member 3 is flush with the upper surface 4a of the light-transmitting member 4. Moreover, it is preferable that the outer peripheral side surface 3c of the covering member 3 is approximately perpendicular to the upper surface 3d of the covering member 3. This configuration provides excellent processability, reduces shape variation of the manufactured light-emitting device, and allows it to be manufactured into an appropriate shape. The covering member 3 is made of a resin material that is softer than the electrodes 22, and the hardness of the covering member 3 is lower than the hardness of the electrodes 22. This makes it possible to easily form the first convex portion 3a1 and the second convex portion 3a2 in the manufacturing process described below.

[0026] (Light-transmitting layer 41 of light-transmitting member 4) The light-transmitting member 4 has a light-transmitting layer 41 disposed on each of the multiple light-emitting elements 2. The light-transmitting member 4 may further include a light diffusion layer 42 that covers an upper surface of the light-transmitting layer 41. When the light diffusion layer 42 is not included, the upper surface 4a of the light-transmitting member 4 becomes the upper surface of the light-transmitting layer 41, and when the light diffusion layer 42 is included, the upper surface 4a of the light-transmitting member 4 becomes the upper surface of the light diffusion layer 42.

[0027] The size of the light-transmitting member 4 may be smaller than, the same as, or larger than the upper surface 2a of the light-emitting element 2 in top view. As an example, as shown in Fig. 1, the light-transmitting member 4 can be arranged so as to be larger than the upper surface 2a of the light-emitting element 2 and to enclose the light-emitting element 2 in top view. The light-transmitting member 4 has the same shape as or a similar shape to the upper surface 2a of the light-emitting element 2. Each of the multiple light-transmitting members 4 provided in the light-emitting device 1 is plate-shaped.

[0028] The area of ​​the light-transmitting member 4 as viewed from above is, for example, 100% to 150% of the area of ​​the light-emitting elements 2 as viewed from above, and preferably 100% to 130%. The light-transmitting members 4 are preferably arranged above the multiple light-emitting elements 2 in the same manner as the light-emitting elements 2 are arranged.

[0029] One or more of the light-transmitting members 4 included in the light-emitting device 1 may have different planar shapes and / or sizes. For example, as shown in FIG. 1, the light-transmitting members 4 arranged on a central light-emitting element 2 may have different sizes from those arranged on an adjacent light-emitting element 2, i.e., on light-emitting elements 2 surrounding the central light-emitting element 2. In this manner, the light-transmitting members 4 may have different planar shapes and / or sizes. It is preferable that the light-transmitting members 4 are arranged in a rectangular shape as a whole in a top view, similar to the arrangement of the light-emitting elements 2.

[0030] The light-transmitting layer 41 of the light-transmitting member 4 is a member that transmits at least a part of the light emitted from the light-emitting element 2, and may transmit 60% or more of the light emitted from the light-emitting element 2 and / or the light whose wavelength has been converted by a phosphor described later, and preferably transmits 70% or more, 75% or more, or 80% or more of the light. The shape of the light-transmitting layer 41 is preferably a plate shape. The thickness of the light-transmitting layer 41 is, for example, 20 μm or more and 400 μm or less.

[0031] Specifically, the light-transmitting layer 41 has an upper surface, a lower surface opposite to the upper surface, and a side surface 4b between the upper surface and the lower surface. The lower surface of the light-transmitting layer 41 is disposed opposite to the upper surface 2a of the light-emitting element 2. The upper and lower surfaces of the light-transmitting layer 41 are preferably flat surfaces parallel to each other, and the side surface 4b may be a surface perpendicular to the upper surface and / or the lower surface, or may have an inclined surface inclined with respect to the upper surface and / or the lower surface.

[0032] The light-transmitting layer 41 can be formed of a light-transmitting resin, glass, ceramics, etc. As the light-transmitting resin, a resin containing one or more of a silicone resin, a modified silicone resin, an epoxy resin, a modified epoxy resin, an acrylic resin, and a fluororesin can be used.

[0033] The light-transmitting layer 41 may contain a phosphor capable of converting the wavelength of at least a part of the incident light. Examples of the light-transmitting layer 41 containing a phosphor include a sintered body of a phosphor, and a light-transmitting resin, glass, ceramics, or the like containing a phosphor powder. Alternatively, the light-transmitting layer 41 may be a resin layer containing a phosphor formed on the surface of a light-transmitting plate that is a molded body of a light-transmitting resin, glass, ceramics, or the like.

[0034] The phosphor is an yttrium-aluminum-garnet phosphor (e.g., Y3(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 phosphors (e.g., Ca 10 (PO4)6Cl2:Eu), SAE phosphors (e.g., Sr4Al 14 O 25 :Eu), chlorosilicate phosphors (e.g., Ca8MgSi4O 16 Cl2:Eu), β-sialon phosphors (e.g., (Si,Al)3(O,N)4:Eu), α-sialon phosphors (e.g., Ca(Si,Al) 12 (O,N) 16: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., K2Si 0.99 Al 0.01 F 5.99 Fluoride-based phosphors such as 3.5MgO·0.5MgF2·GeO2:Mn) or MGF-based phosphors (e.g., 3.5MgO·0.5MgF2·GeO2:Mn), phosphors having a perovskite structure (e.g., CsPb(F,Cl,Br,I)3), or quantum dot phosphors (e.g., CdSe, InP, AgInS2, or AgInSe2) can be used.

[0035] The light-transmitting layers 41 of the light-emitting device 1 may be partially or entirely made of a light-transmitting material, or may contain a phosphor. In this case, the light-transmitting layers 41 may contain the same phosphor or may contain different phosphors. All of the light-transmitting layers 41 may contain a phosphor that is excited by blue light and emits yellow light. Some of the light-transmitting layers 41 may contain a phosphor that is excited by blue light and emits yellow light, and the other may contain a phosphor that is excited by blue light and emits orange light. By adjusting the type or content of the phosphor contained in the light-transmitting layers 41, light of a desired color can be emitted from the upper surface of the light-transmitting layers 41.

[0036] The light-transmitting layer 41 may contain a light-diffusing material. Examples of the light-diffusing material include particles of titanium oxide, aluminum oxide, silicon oxide, zinc oxide, and the like. By dispersing such a light-diffusing material in the light-transmitting member or by providing such particles in the light-transmitting layer 41, the light emitted from the light-emitting element 2 can be diffused and released to the outside. This can reduce uneven light emission on the upper surface of the light-transmitting layer 41.

[0037] (Light diffusion layer 42 of light-transmitting member 4) The light emitting device 1 of the present embodiment may further include a light diffusion layer 42 that covers the upper surface of the light transmitting layer 41. The light diffusion layer 42 may cover only a part of the light transmitting layer 41, but it is preferable that the light diffusion layer 42 integrally covers the entire light transmitting layer 41. In this case, the light diffusion layer 42 may cover the entire upper surface of the light emitting device 1 including the covering member 3 between adjacent light transmitting layers 41. This makes it possible to reduce the non-light emitting region between adjacent light emitting regions from being viewed from the outside as a region with low brightness when adjacent light emitting elements 2 are turned on.

[0038] The light diffusion layer 42 has a function of diffusing and guiding the light emitted from the light emitting element 2. The light diffusion layer 42 may be a single layer, or may have a laminated structure including a plurality of layers. The light diffusion layer 42 has, for example, a total light transmittance (Tr) of 30% to 99% and a diffusivity (D) of 10% to 90%. The thickness of the light diffusion layer 42 can be, for example, 10 μm or more and 200 μm or less.

[0039] The light diffusion layer 42 may be in contact with the upper surface of the light-transmitting layer 41, or may be disposed at a distance from the upper surface of the light-transmitting layer 41. In particular, it is preferable that the lower surface of the light diffusion layer 42 is in direct contact with the upper surface of the light-transmitting layer 41. This allows the light from the light-emitting element 2 to be efficiently introduced into the light diffusion layer 42, thereby improving the light extraction efficiency.

[0040] The light diffusion layer 42 includes a light-transmitting resin and a light-diffusing substance contained in the light-transmitting resin. The light-transmitting resin and the light-diffusing substance may be the same as the light-transmitting resin and the light-diffusing substance used in the covering member 3. Furthermore, the light diffusion layer 42 may be formed of a resin that has low absorption of visible light, such as a polycarbonate resin, a polystyrene resin, or a polyethylene resin. The upper surface 4a of the light diffusion layer 42 may be flat or may have fine irregularities on the surface.

[0041] (Dimensions of light emitting device 1) 4 shows an example of an arrangement of a plurality of light emitting devices 1 according to the embodiment. The light emitting device 1 of the present embodiment is formed by collectively forming a plurality of light emitting devices 1, and then cutting each of the plurality of light emitting devices 1 into individual pieces as shown in FIG.

[0042] The light emitting device 1 of this embodiment can have the following dimensions, for example. 2.0mm ≦ Lx1 ≦ 3.0mm 2.5mm ≦ Ly1 ≦ 3.5mm however, Lx1 is the dimension of one light-emitting device 1 in the x direction, Ly1 is the dimension of one light-emitting device 1 in the y direction, It is.

[0043] Moreover, the portion of the outer peripheral region 1a of the light emitting device 1 of this embodiment excluding the covering member 3 preferably has the following dimensions, for example. 1.5mm ≦ Lx2 ≦ 2.5mm 2.0mm ≦ Ly2 ≦ 3.0mm however, Lx2 is the dimension in the x direction of the outer peripheral region 1a of one light-emitting device 1 excluding the covering member 3, Ly2 is the dimension in the y direction of the outer peripheral region 1a of one light-emitting device 1 excluding the covering member 3, It is.

[0044] Furthermore, the lengths Ax1, Bx1, Ay1, and Ay2 of the sides of the light-emitting element 2 of this embodiment in the top view may be, for example, 100 μm or more and 3000 μm or less, as described above.

[0045] The dimensions between adjacent light emitting devices 1 before singulation are preferably as follows. 0.3mm ≦ Dx 0.3mm≦Dy however, Dx is the dimension in the x direction between the light emitting devices 1, Dy is the dimension between the light-emitting devices 1 in the y direction, It is.

[0046] Moreover, the dimensions between adjacent light emitting devices 1 in this embodiment are more preferably as follows. 0.37mm ≦ Dx 0.37mm≦Dy The light emitting device 1 is manufactured as an assembly of a plurality of light emitting devices 1, and can be separated into individual units using, for example, a blade having a width of Dx and Dy.

[0047] In this embodiment, the distance between adjacent light emitting elements 2 is preferably as follows. 0.05mm≦dx1 0.05mm ≦ dy1 however, dx1 is the distance in the x direction between the light-emitting elements 2, dy1 is the distance in the y direction between the light-emitting elements 2, It is.

[0048] Moreover, in this embodiment, the distance between adjacent light emitting elements 2 is more preferably as follows. 0.09mm≦dx1 0.09mm ≦ dy1

[0049] The covering member 3 of this embodiment is installed on the entire outer peripheral region 1a of the multiple light-emitting elements 2 of the light-emitting device 1. As shown below, the distance Wx1 in the x direction from the outer peripheral side surface 3c of the light-emitting device 1 to the side surface 2b of the light-emitting element 2 is longer than the distance dx1 between the light-emitting elements 2 in the x direction, and the distance Wy1 in the y direction from the outer peripheral side surface 3c of the light-emitting device 1 to the side surface 2b of the light-emitting element 2 is longer than the distance dy1 between the light-emitting elements 2 in the y direction. dx1 < Wx1 dy1 < Wy1

[0050] In this embodiment, the distance Wx1 from the outer peripheral side surface 3c of the light-emitting device 1 in the x direction to the side surface 2b of the light-emitting element 2 and the distance Wy1 from the outer peripheral side surface 3c of the light-emitting device 1 in the y direction to the side surface 2b of the light-emitting element 2 are preferably dimensions as follows. 0.2mm ≦ Wx1 0.2mm ≦ Wy1

[0051] Such dimensions enable the light emitted from the light-emitting element 2 positioned outside all of the plurality of light-emitting elements 2 to be distributed upward, thereby reducing light leakage from the side surface of the light-emitting device 1. Each of Wx1 and Wy1 is preferably in the range of, for example, 5% to 200% of the width of the light-emitting element 2 in the same direction.

[0052] Moreover, it is preferable that the distance dx2 between adjacent light-transmissive members 4 in the x direction and the distance dy2 between adjacent light-transmissive members 4 in the y direction are smaller than the distances dx1 and dy1 between adjacent light-emitting elements 2, respectively. This makes it possible to further reduce the low-luminance region between adjacent light-emitting elements 2. For example, the distance may be 5% or more and 50% or less of the length of one side of the light-emitting element 2. Specifically, the distance dx2 and the distance dy2 between the light-transmissive members 4 may be 10 μm or more and 100 μm or less, respectively. The distances dx2 and dy2 between the light-transmissive members 4 may be the same or different.

[0053] (Substrate 6) Fig. 5 is a cross-sectional view showing an example in which the light emitting device 1 according to the embodiment is mounted on a substrate 6. Fig. 5 is a cross-sectional view of the light emitting device 1 taken along line III-III in Fig. 1. The substrate 6 has wiring 61 connected to the light emitting elements 2 on at least its upper surface 6a. Specifically, in the light emitting device 1, the positive and negative electrodes 22 of each of the multiple light emitting elements 2 are electrically joined to the wiring 61 of the substrate 6 via a joining member 7.

[0054] The substrate 6 may be a flexible printed circuit board (FPC) that can be manufactured by a roll-to-roll method, may be a substrate that is thin enough to be bendable, or may be a rigid substrate.

[0055] The substrate 6 can be made of, for example, ceramics such as aluminum oxide, aluminum nitride, silicon nitride, and mullite; thermoplastic resins such as PA (polyamide), PPA (polyphthalamide), PPS (polyphenylene sulfide), and liquid crystal polymer; and resins such as epoxy resin, silicone resin, modified epoxy resin, urethane resin, and phenol resin.

[0056] The wiring 61 may be disposed not only on the upper surface 6a of the substrate 6 but also on the lower surface. The wiring 61 on the upper and lower surfaces may be connected via wiring 61 disposed on the side surface, or via an inner layer wiring such as a via. The wiring 61 may have a thickness that differs in parts. The wiring 61 may be formed by electrolytic plating, electroless plating, sputtering, vapor deposition, or the like. Examples of materials for the wiring 61 include metals such as iron, copper, nickel, aluminum, gold, platinum, titanium, tungsten, and palladium, or alloys containing these metals.

[0057] (Joint material 7) The bonding member 7 electrically connects the wiring 61 of the substrate 6 and the electrode 22 of the light emitting element 2. For example, the bonding member 7 may be eutectic solder, conductive paste, bumps, etc. The bonding member 7 of the light emitting device 1 of the present embodiment uses eutectic solder.

[0058] (Relationship between the covering member 3, the substrate 6, and the joining member 7) In the light emitting device 1 of this embodiment, when the light emitting element 2 is mounted on the substrate 6 via the bonding member 7, the first convex portion 3a1 is located below the lower surface 22b of the positive and negative electrodes 22. Therefore, in the light emitting device 1, short circuits between the electrodes 22 are less likely to occur, and many small light emitting elements 2 can be arranged closely together.

[0059] In the light emitting device 1 of this embodiment, the light emitting element 2 is bonded to the substrate 6 via the bonding member 7. At this time, the second convex portion 3a2 comes into contact with the substrate 6. The second convex portion 3a2 is arranged to include at least vertices T1, T2, and T3 that form a triangle T surrounding the center C of the light emitting device 1 in a top view. Therefore, the light emitting device 1 before bonding can be stably arranged on the substrate 6. In addition, the volume of the bonding member 7 that bonds the light emitting device 1 to the substrate 6 can be increased by the height of the second convex portion 3a2, and the bonding property between the light emitting element 2 and the substrate 6 can be improved. In addition, since the second convex portion 3a2 can keep the distance between the light emitting element 2 and the substrate 6 constant, even if the amount of the bonding member 7 applied is increased, the light emitting device 1 can be reduced from being mounted at an angle with respect to the substrate 6.

[0060] In addition, the second convex portion 3a2 in this embodiment is arranged in a frame shape that at least partially surrounds the light emitting element 2 in top view, and the bonding member 7 is located inside the second convex portion 3a2 in top view. This can reduce the bonding member 7 from spreading outward from the light emitting device 1 in top view. Furthermore, the second convex portion 3a2 is arranged in a frame shape that surrounds all of the multiple light emitting elements 2, so that the bonding member 7 can reduce the spreading outward from the light emitting device 1 over the entire periphery in top view. This makes it possible to arrange other electronic components close to the light emitting device 1 on the substrate 6, for example, and to reduce the size of the light emitting device 1 or a light source device using the light emitting device 1.

[0061] (Method of Manufacturing Light-Emitting Device 1) 6 is a flow chart showing an example of a method for manufacturing the light emitting device 1 according to this embodiment. The method for manufacturing the light emitting device 1 having the above-mentioned configuration will be described along with steps S1 to S9 shown in FIG.

[0062] (Step S1 of Preparing Light-Transmitting Member 4) 7A shows an example of step S1 of preparing a light-transmitting member 4 in the manufacturing method of the light-emitting device 1 according to the embodiment. In the manufacturing method of the light-emitting device 1, first, a laminate of a light-transmitting sheet 51 having a size capable of being divided into a plurality of light-transmitting layers 41 and a light diffusion sheet 52 having a size capable of being divided into a plurality of light diffusion layers 42 is prepared (S1). The light-transmitting sheet 51 and the light diffusion sheet 52 are laminated in a predetermined size. Note that FIGS. 7A to 7G show a part of the light-transmitting sheet 51 and the light diffusion sheet 52, and in reality, a laminate having a size capable of being divided into a plurality of light-emitting devices 1 as shown in FIG. 4 is prepared.

[0063] (Step S2 of processing the light-transmitting member 4) FIG. 7B shows an example of step S2 of processing the light-transmitting member 4 in the manufacturing method of the light-emitting device 1 according to the embodiment. In the manufacturing method of the light-emitting device 1, following step S1, a laminate of the light-transmitting sheet 51 and the light diffusion sheet 52 is processed (S2). Specifically, in the laminate of the light-transmitting sheet 51 and the light diffusion sheet 52, a slit is formed from the light-transmitting sheet 51 side to divide the light-transmitting sheet 51. Note that the slit only needs to reach the light diffusion sheet 52, and the light diffusion sheet 52 may or may not be divided. Here, the sheet-like light-transmitting sheet 51 and the light diffusion sheet 52 laminated in S1 are divided into a plurality of light-transmitting members 4 by the slit. Note that, for ease of understanding, in the subsequent steps, the individualized light-transmitting sheet 51 constitutes the light-transmitting layer 41, the light diffusion sheet 52 constitutes the light diffusion layer 42, and the light-transmitting layer 41 and the light diffusion layer 42 constitute the light-transmitting member 4.

[0064] (Step S3 of arranging the light-emitting element 2) 7C shows an example of step S3 of arranging the light-emitting elements 2 in the manufacturing method of the light-emitting device 1 according to the embodiment. In the manufacturing method of the light-emitting device 1, following step S2, the light-emitting elements 2 are arranged on the light-transmitting member 4 (S3). The light-emitting elements 2 are arranged with the surfaces opposite to the electrode 22 facing each of the light-transmitting members 4 separated in S2.

[0065] (Step S4 of placing covering member 3) 7D shows an example of step S4 of arranging the covering member 3 in the manufacturing method of the light emitting device 1 according to the embodiment. In the manufacturing method of the light emitting device 1, following step S3, the covering member 3 is arranged (S3). The covering member 3 is arranged so as to cover the light emitting element 2 and the side surface 4b of the light-transmitting member 4 arranged in S3.

[0066] (Step S5 of grinding the coating member 3) FIG. 7E shows an example of step S5 of grinding the covering member 3 in the manufacturing method of the light emitting device 1 according to the embodiment. In the manufacturing method of the light emitting device 1, following step S4, the covering member 3 is ground (S5). Here, for example, a grinding and polishing device is used to remove a part of the covering member 3. Specifically, this is performed by pressing a grindstone W of the grinding and polishing device against the covering member 3 to grind and polish it. The covering member 3 is ground so as to be flush with the electrode 22. Here, being flush may mean being completely flush, or may include some misalignment.

[0067] (Step S6 of forming the first convex portion 3a1 and the second convex portion 3a2) 7F shows an example of a light emitting device 1 formed through step S6 of forming the first convex portion 3a1 and the second convex portion 3a2 in the manufacturing method of the light emitting device 1 according to the embodiment. In the manufacturing method of the light emitting device 1, following step S5 of grinding the covering member 3, grinding is further performed to a height at which the electrode 22 is exposed, thereby forming the first convex portion 3a1 and the second convex portion 3a2 (S6). In other words, step S6 of forming the first convex portion 3a1 and the second convex portion 3a2 can be performed simultaneously with step S5 of grinding the covering member 3.

[0068] More specifically, as shown in FIG. 7E, in the grinding step S5, grinding is performed by pressing the grindstone W against the coating member 3. The pressing is performed, for example, with a pressing force of 0.2 N·m to 2 N·m, and preferably with a pressing force of 0.4 N·m to 0.7 N·m. Here, since the coating member 3 is made of resin, grinding and polishing are performed in a state in which it is deformed by pressing the grindstone W against it. Therefore, when the pressing force from the grindstone W is released after the grinding and polishing is completed, the coating member 3 expands to return to its original shape. This allows the height of the coating member 3 to be higher than the electrode 22, as shown in FIG. 7F. In other words, by using a resin that is softer and less hard than the electrode 22 for the coating member 3, the electrode 22 can be ground in a state in which the coating member 3 is pressed. Then, after the electrode 22 is exposed, the coating member 3 that has been pressed to the height of the electrode 22 surface expands, forming the first convex portion 3a1 and the second convex portion 3a2.

[0069] The first convex portion 3a1 and the second convex portion 3a2 of this embodiment are formed naturally when the covering member 3 and the electrode 22 are ground. The length α of the first convex portion 3a1 and the length β of the second convex portion 3a2 can be adjusted by the interval between the electrodes 22. The wider the interval between the electrodes 22, the longer the length α of the first convex portion 3a1 and the length β of the second convex portion 3a2. The length β of the second convex portion 3a2 can also be adjusted by adjusting the dimension between the adjacent light emitting devices (Dx, Dy in FIG. 4). A mold may be formed in advance between the electrodes 22, and the shape of the expanded covering member 3, the length α of the first convex portion 3a1, the length β of the second convex portion 3a2, etc. may be determined by the mold.

[0070] (Step S7 of forming protective portion 22a) FIG. 7G shows an example of step S7 of forming the protective portion 22a in the manufacturing method of the light emitting device 1 according to the embodiment. In the manufacturing method of the light emitting device 1, the protective portion 22a is subsequently formed (S7). The protective portion 22a uses a conductive metal and covers the exposed surface to protect the electrode 22. The material of the protective portion 22a may be a metal such as copper, aluminum, gold, silver, platinum, titanium, tungsten, palladium, iron, nickel, or an alloy containing these metals. The protective portion 22a may be partially removed by, for example, etching, laser ablation, or the like. The thickness of the protective portion 22a may be appropriately set depending on the performance to be obtained, the material to be used, and the like. For example, when removing a portion of the protective portion 22a by laser ablation, the thickness of the protective portion 22a is preferably 1 μm or less, and more preferably 125 angstroms or more and 1000 angstroms or less.

[0071] (Steps S8 and S9 for forming the light-emitting surface and dividing it into individual pieces) FIG. 7H shows an example of step S8 of forming a light-emitting surface and dividing the light-emitting device 1 according to the embodiment. In the manufacturing method of the light-emitting device 1, the surface of the light-transmitting member 4 is subsequently ground to form a light-emitting surface (S7). The light-emitting surface is the upper surface 4a of the light-transmitting member 4. In the manufacturing method of the light-emitting device 1, the light-emitting device 1 is subsequently divided into individual light-emitting devices 1 (S8). By grinding the surface of the light-transmitting member 4, a smooth light-emitting surface can be formed. In addition, the light-emitting device 1 is divided into individual packages each including the light-emitting device 1, and the light-emitting device 1 is completed. The outer peripheral side surface 3c of the divided covering member 3 is perpendicular to the upper surface 3d of the covering member 3. It is preferable to manufacture the outer peripheral side surface 3c and the upper surface 3d of the covering member 3 perpendicularly, since the setting of the processing machine is simple.

[0072] (Step S10 of mounting the substrate 6) The light emitting device 1 may include a substrate 6 on which the light emitting element 2 is mounted. FIG. 7I shows an example of step S10 of mounting the light emitting element 2 on the substrate 6 in the manufacturing method of the light emitting device 1 according to the embodiment. The manufacturing method of the light emitting device 1 may include a step of mounting the light emitting element 2 on the substrate 6 (S10). The light emitting element 2 and the substrate 6 are bonded by a bonding member 7. The bonding member 7 bonds the wiring 61 of the substrate 6 and the protective portion 22a of the electrode 22 of the light emitting element 2. The bonding member 7 is, for example, a eutectic solder. In the mounting step S10, the covering member 3 has the first convex portion 3a1 and the second convex portion 3a2, so that it is possible to reduce the unintended lateral spreading of the eutectic solder applied on the substrate 6 during reflow. This makes it easier to arrange the eutectic solder after reflow at the desired position of the wiring 61, and the light emitting device 1 can have excellent bonding properties with the substrate 6.

[0073] (Other embodiments) FIG. 8 shows an example of a light emitting device 1 according to another embodiment. The second convex portion 3a2 of the light emitting device 1 according to the embodiment shown in FIG. 8 is arranged to include at least vertices T1, T2, and T3 that form a triangle T surrounding the center C of the light emitting device 1 in a top view, and is located at least in a part of the outer peripheral region 1a surrounding the plurality of light emitting elements 2. Since the light emitting device 2 is supported at three or more positions on the substrate 6 and the second convex portion 3a2 is located at least in a part of the outer peripheral region 1a surrounding the plurality of light emitting elements 2, the light emitting element 2 can be supported on the substrate 6 in the outer peripheral region 1a and can be stably joined to the substrate 6. In addition, since the space between the first convex portion 3a1 and the substrate 6 is open to the outside, heat generated when the light emitting device is turned on can be efficiently released to the outside, and the light emitting device 1 has excellent heat dissipation properties.

[0074] (Other embodiments) FIG. 9 shows an example of a light emitting device 1 according to another embodiment. The second convex portion 3a2 of the light emitting device 1 of the embodiment shown in FIG. 9 is arranged to include at least vertices T1, T2, and T3 that form a triangle T surrounding the center C of the light emitting device 1 when viewed from above. Since the light emitting device 1 is supported at three or more positions on the substrate 6, it can be stably joined to the substrate 6. In addition, since the space between the first convex portion 3a1 and the substrate 6 is open to the outside, heat generated when the light emitting device is turned on can be efficiently released to the outside, and the light emitting device 1 can have excellent heat dissipation properties. Note that the vertices T1, T2, and T3 only need to form a triangle T surrounding the center C, and do not necessarily need to be present in the outer circumferential region 1a.

[0075] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and can be modified as appropriate without departing from the technical spirit of the present disclosure.

[0076] The light emitting device 1 is a device used as a light source for any purpose. The light emitting device 1 can be suitably used for various purposes such as lighting, in-vehicle, display device, electronic device, etc. The light emitting device 1 may function not only as a single device, but also in combination with other parts or members.

[0077] In addition to the above-described embodiment, the following supplementary notes are further disclosed. (Appendix 1) A plurality of light emitting elements each having a semiconductor laminate and positive and negative electrodes disposed on a lower surface side of the semiconductor laminate; a covering member that collectively covers the side surfaces of the plurality of light emitting elements; A light emitting device comprising: The underside of the covering member is one or more first protrusions located below the lower surfaces of the positive and negative electrodes; One or more second protrusions located below the first protrusions; having The one or more second protrusions are arranged so as to include at least vertices that form a triangle surrounding the center of the light emitting device in a top view. Light emitting device. (Appendix 2) the first convex portion is located between adjacent light emitting elements and between adjacent positive and negative electrodes, the second protrusion is located in at least a part of an outer circumferential region surrounding the plurality of light emitting elements; 2. The light-emitting device of claim 1. (Appendix 3) the second protrusion is disposed in a frame shape, at least a portion of which surrounds the light emitting element, when viewed from above. 3. The light-emitting device according to claim 1 or 2. (Appendix 4) Further comprising a substrate on which the light emitting device is mounted, the second protrusion is in contact with the substrate, the first protrusion is not in contact with the substrate; 4. The light emitting device according to claim 1 . (Appendix 5) the substrate includes wiring arranged on an upper surface of the substrate so as to face the positive and negative electrodes of the light-emitting element; The positive and negative electrodes are connected to the wiring via a bonding member, The bonding member is located inside the second protrusion in a top view. 5. The light-emitting device of claim 4. (Appendix 6) a light-transmitting member disposed on an upper surface of the plurality of light-emitting elements; the covering member covers a side surface of the light-transmitting member, The upper surface of the covering member is flush with the upper surface of the light-transmitting member. 6. The light emitting device according to claim 1 . (Appendix 7) The hardness of the covering member is lower than the hardness of the electrode. 7. The light-emitting device of claim 6. (Appendix 8) The outer peripheral side surface of the covering member is perpendicular to the upper surface of the covering member. 8. The light emitting device according to claim 1 . [Explanation of symbols]

[0078] Reference Signs List 1...light emitting device, 2...light emitting element, 21...semiconductor laminate, 22...electrode, 22a...protective portion, 3...covering member, 3a1...first convex portion, 3a2...second convex portion, 4...light-transmitting member, 41...light-transmitting layer, 42...light diffusion layer, 6...substrate, 61...wiring, 7...jointing member, T...triangle, T1, T2, T3...vertex, W...grindstone

Claims

1. A semiconductor laminate and a plurality of light emitting elements each having positive and negative electrodes disposed on a lower surface side of the semiconductor laminate; a covering member that collectively covers the side surfaces of the plurality of light emitting elements; A light emitting device comprising: The underside of the covering member is one or more first protrusions located below the lower surfaces of the positive and negative electrodes; One or more second convex portions located below the first convex portions; having The one or more second protrusions are arranged so as to include at least vertices that form a triangle surrounding the center of the light emitting device in a top view. Light emitting device.

2. the first convex portion is located between adjacent light emitting elements and between adjacent positive and negative electrodes, The second convex portion is located in at least a part of an outer circumferential region surrounding the plurality of light emitting elements. The light emitting device according to claim 1 .

3. the second protrusion is disposed in a frame shape, at least a portion of which surrounds the light emitting element, when viewed from above; The light emitting device according to claim 1 .

4. Further comprising a substrate on which the light emitting device is mounted, the second protrusion is in contact with the substrate, the first protrusion is not in contact with the substrate; A light emitting device according to claim 1 .

5. the substrate includes wiring arranged on an upper surface of the substrate so as to face the positive and negative electrodes of the light-emitting element; The positive and negative electrodes are connected to the wiring via a bonding member, The joining member is located inside the second protrusion in a top view. The light emitting device according to claim 4.

6. a light-transmitting member disposed on an upper surface of the plurality of light-emitting elements; the covering member covers a side surface of the light-transmitting member, The upper surface of the covering member is flush with the upper surface of the light-transmitting member. The light emitting device according to claim 1 .

7. The hardness of the covering member is lower than the hardness of the electrode. The light emitting device according to claim 6.

8. The outer peripheral side surface of the covering member is perpendicular to the upper surface of the covering member. The light emitting device according to claim 1 .

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