Light emitting device and illumination device

Abstract

To provide a light emitting device and an illumination device that can increase luminous efficacy.SOLUTION: A light emitting device comprises: a substrate that has a first surface; a light emitting device that is mounted on the first surface of the substrate and emits excitation light; and a wavelength conversion member that is in contact with the entirety of at least an end of the first surface of the substrate. The wavelength conversion member has a portion that spreads to the outside beyond at least part of the end of the first surface of the substrate in plan view of the first surface of the substrate.SELECTED DRAWING: Figure 1

Description

Cross-reference to related applications

[0001] This application claims the priority of Japanese Patent Application No. 2021-158465 (filed on September 28, 2021), and the entire disclosure of the said application is incorporated herein by reference.

Technical field

[0002] This disclosure relates to a light-emitting device and a lighting device.

Background art

[0003] An optoelectronic device in which a light-emitting semiconductor chip and a conversion member for wavelength conversion are disposed on a support is known (see, for example, Patent Document 1).

Prior art documents

Patent documents

[0004]

Patent Document 1

Summary of the invention

[0005] A light-emitting device according to an embodiment of the present disclosure includes a substrate having a first surface, a light-emitting element located on the first surface of the substrate and emitting excitation light, and a wavelength conversion member that contacts at least the entire end portion of the first surface of the substrate. The wavelength conversion member has a portion that extends outside at least a part of the end portion of the first surface of the substrate in a plan view of the first surface of the substrate.

[0006] A lighting device according to an embodiment of the present disclosure includes the light-emitting device and a mounting board on which the light-emitting device is mounted.

Brief description of the drawings

[0007]

Figure 1

Figure 2

Figure 3

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Figure 6

Figure 7A

Figure 7B

Figure 8A

Figure 8B

Figure 9

Mode for Carrying Out the Invention

[0008] (Configuration Example of Light-Emitting Device 10) As shown in FIGS. 1, 2, and 3, the light-emitting device 10 includes an element substrate 2, a light-emitting element 3, and a wavelength conversion member 6. The light-emitting element 3 is located on the positive side of the Z axis of the element substrate 2. The wavelength conversion member 6 is located on the positive side of the Z axis of the element substrate 2 and the light-emitting element 3.

[0009] As shown in FIG. 3, the element substrate 2 includes a first surface 2A facing the positive direction of the Z axis and a second surface 2B facing the negative direction of the Z axis. The positive side of the Z axis of the element substrate 2 is also referred to as the front surface side. The negative side of the Z axis of the element substrate 2 is also referred to as the back surface side. The element substrate 2 further includes a side surface 2C that intersects the first surface 2A and the second surface 2B. The side surface 2C of the element substrate 2 is also referred to as the substrate side surface. The first surface 2A has a side that intersects the side surface 2C. The side of the first surface 2A, or the region within a predetermined distance from the side, is also referred to as the end portion 2D of the first surface 2A.

[0010] The element substrate 2 includes a first electrode 41 and a second electrode 42 on a first surface 2A on the front surface side. The first electrode 41 is located on the positive X-axis direction side of the second electrode 42. The first electrode 41 and the second electrode 42 are each arranged in two side by side along the Y-axis. The first electrode 41 and the second electrode 42 located on the positive Y-axis direction side are electrically connected. The first electrode 41 and the second electrode 42 located on the negative Y-axis direction side are electrically connected. That is, the element substrate 2 includes two electrodes to which the first electrode 41 and the second electrode 42 are connected. The element substrate 2 includes two back electrodes 44 on a second surface 2B on the back surface side. The two electrodes located on the front surface side and the two back electrodes 44 located on the back surface side are electrically connected by wirings penetrating the element substrate 2 respectively. Specifically, one electrode located on the positive Y-axis direction side on the front surface side and one back electrode 44 located on the positive Y-axis direction side on the back surface side are electrically connected. Also, one electrode located on the negative Y-axis direction side on the front surface side and one back electrode 44 located on the negative Y-axis direction side on the back surface side are electrically connected.

[0011] The element substrate 2 further includes a reflecting member 43 that spreads over a portion of the first surface 2A on the front surface side where no electrode is located. The reflecting member 43 spreads to an end portion 2D of the first surface 2A. In a plan view of the first surface 2A of the element substrate 2, the reflecting member 43 is positioned so as to surround the light-emitting element 3.

[0012] The light-emitting element 3 is electrically connected to the first electrode 41. The light-emitting element 3 operates with electric power supplied from the back electrode 44 to the first electrode 41. The light-emitting element 3 emits light having a peak wavelength in a wavelength region of, for example, 360 nm or more and 430 nm or less. The wavelength region of 360 nm or more and 430 nm or less is also referred to as a violet light region.

[0013] The wavelength conversion member 6 converts the light incident on the wavelength conversion member 6 from the light emitting element 3 into light having a peak wavelength in a wavelength region of, for example, 360 nm or more and 780 nm or less, and emits the converted light. The wavelength region of 360 nm or more and 950 nm or less is also referred to as the visible light region. The wavelength conversion member 6 emits a peak wavelength region in the visible light region by being excited by the light emitted from the light emitting element 3. The light emitted from the light emitting element 3 is also referred to as excitation light. The light emitting element 3 included in the light emitting device 10 is also referred to as an excitation light emitting element.

[0014] The light emitting device 10 may further include an electronic component 7. The electronic component 7 may be, for example, a Schottky diode. The electronic component 7 is electrically connected to the second electrode 42. The electronic component 7 is configured to be able to control the voltage between two electrodes located on the surface side. The first electrode 41 and the second electrode 42 are connected by a connection conductor path 45.

[0015] Hereinafter, specific examples of each configuration of the light emitting device 10 will be described.

[0016] <Element substrate 2> The element substrate 2 is also simply referred to as a substrate. The element substrate 2 may be formed of, for example, a material having insulating properties. The element substrate 2 may be formed of, for example, a ceramic material such as aluminum oxide (alumina) or mullite, a glass ceramic material, or a composite material in which a plurality of these materials are mixed. The element substrate 2 may also be formed of a polymer resin material in which metal oxide fine particles capable of adjusting thermal expansion are dispersed. The element substrate 2 may be configured to include aluminum nitride or silicon carbide. Thereby, the thermal conductivity of the element substrate 2 can be improved, and the heat dissipation performance of the light emitting device 10 is improved. In the present embodiment, it is assumed that the element substrate 2 is configured with aluminum nitride as a material.

[0017] The first electrode 41, the second electrode 42, and the back surface electrode 44, as well as the wiring penetrating the element substrate 2, may be formed of a conductive material such as tungsten, molybdenum, manganese, or copper, for example. The reflecting member 43 may be formed of a material obtained by adding a white material such as titanium oxide to a silicone resin-based material, for example. The reflecting member 43 is not limited to this example and may be formed such that the reflectance of the reflecting member 43 is higher than the reflectance of the first surface 2A. When the reflecting member 43 is positioned on the first surface 2A, the excitation light emitted from the light emitting element 3 and the illumination light converted by the wavelength conversion member 6 are less likely to be absorbed by the first surface 2A. As a result, the excitation light and the illumination light can be efficiently emitted to the outside of the light emitting device 10.

[0018] <Light emitting element 3> It is assumed that the light emitting element 3 is an LED (Light Emitting Diode). In the PN junction where the P-type semiconductor and the N-type semiconductor are joined, the LED emits light to the outside when electrons and holes recombine. The light emitting element 3 is not limited to an LED and may be other light emitting devices.

[0019] The light emitting element 3 is mounted on the first surface 2A of the element substrate 2. The light emitting element 3 is electrically connected to the first electrode 41 disposed on the first surface 2A of the element substrate 2 via, for example, a brazing material or solder. The first electrode 41 is provided in a set of two so as to be connected to the positive and negative electrodes of the light emitting element 3, respectively. The light emitting element 3 is positioned on the first electrode 41 so as to cover at least a part of the first electrode 41 in the plan view of the first surface 2A of the element substrate 2. The light emitting element 3 may be larger than the first electrode 41 in the plan view.

[0020] The light-emitting element 3 may be mounted on the element substrate 2 by flip-chip bonding. When the light-emitting element 3 is mounted by flip-chip bonding, the first electrode 41 and the brazing material or solder etc. are positioned so as to be covered by the light-emitting element 3 in a plan view of the first surface 2A. By covering the first electrode 41 and the brazing material or solder etc. with the light-emitting element 3, it becomes difficult for the excitation light emitted from the light-emitting element 3 or the illumination light converted by the wavelength conversion member 6 to enter the first electrode 41 and the brazing material or solder etc. As a result, it becomes difficult for the excitation light or the illumination light to be absorbed by the first electrode 41 and the brazing material or solder etc. As a result, the luminous efficiency of the light-emitting device 10 can be further enhanced.

[0021] As a comparative example, when the light-emitting element 3 is mounted on the element substrate 2 by wire bonding, at least a part of the wire is not covered by the light-emitting element 3. In this case, the excitation light or the illumination light can be absorbed by the wire. In the light-emitting device 10 according to the present embodiment, since the light-emitting element 3 is mounted on the element substrate 2 by flip-chip bonding, it becomes more difficult for the excitation light or the illumination light to be absorbed than in the case of wire bonding as in the comparative example. As a result, the luminous efficiency of the light-emitting device 10 can be further enhanced.

[0022] The number of the light-emitting elements 3 mounted on the first surface 2A of the element substrate 2 is one in FIG. 1 etc., but is not particularly limited and may be two or more. When the number of the light-emitting elements 3 is two or more, each light-emitting element 3 is positioned so as not to overlap with each other in a plan view of the first surface 2A.

[0023] The light-emitting element 3 may include a translucent substrate and a semiconductor light layer formed on the translucent substrate. The translucent substrate includes a material on which a semiconductor light layer can be grown using, for example, a chemical vapor deposition method such as metalorganic chemical vapor deposition or molecular beam epitaxy. The translucent substrate may be formed of, for example, sapphire, gallium nitride, aluminum nitride, zinc oxide, zinc selenide, silicon carbide, silicon (Si), or zirconium diboride etc. The thickness of the translucent substrate may be, for example, 50 μm or more and 1000 μm or less.

[0024] The optical semiconductor layer may include a first semiconductor layer formed on a translucent substrate, a light-emitting layer formed on the first semiconductor layer, and a second semiconductor layer formed on the light-emitting layer. The first semiconductor layer, the light-emitting layer, and the second semiconductor layer may be formed of, for example, a group III nitride semiconductor, a group III-V semiconductor such as gallium phosphide or gallium arsenide, or a group III nitride semiconductor such as gallium nitride, aluminum nitride, or indium nitride.

[0025] The thickness of the first semiconductor layer may be, for example, 1 μm or more and 5 μm or less. The thickness of the light-emitting layer may be, for example, 25 nm or more and 150 nm or less. The thickness of the second semiconductor layer may be, for example, 50 nm or more and 600 nm or less.

[0026] <Wavelength conversion member 6> The wavelength conversion member 6 is located on the first surface 2A of the element substrate 2. The wavelength conversion member 6 seals the light-emitting element 3 by filling the space above the light-emitting element 3. The wavelength conversion member 6 may be formed by being applied in a paste state on the first surface 2A of the element substrate 2 and then cured. The wavelength conversion member 6 may also be formed by being pasted on the first surface 2A of the element substrate 2 in a sheet state and then cured.

[0027] The excitation light emitted from the light-emitting element 3 directly enters the wavelength conversion member 6. The wavelength conversion member 6 converts the incident excitation light into light having a peak wavelength included in a wavelength region of, for example, 360 nm or more and 780 nm or less, and emits the converted light.

[0028] The wavelength conversion member 6 may include a translucent member having translucency and a phosphor.

[0029] The translucent member may be formed of, for example, an insulating resin material having light transmittance such as a fluororesin, a silicone resin, an acrylic resin, or an epoxy resin, or a glass material having light transmittance. The refractive index of the translucent member may be set to, for example, 1.4 or more and 1.6 or less.

[0030] The phosphor is assumed to be contained inside the translucent member. The phosphor may be dispersed substantially uniformly inside the translucent member. The phosphor converts the incident excitation light into light having various peak wavelengths.

[0031] The phosphor may convert the excitation light into light specified by a spectrum having a peak wavelength in a wavelength region from, for example, 400 nm to 500 nm, that is, blue light. In this case, the phosphor may include, for example, BaMgAl 10 O 17 :Eu, or (Sr,Ca,Ba) 10 (PO4)6Cl2:Eu,(Sr,Ba) 10 (PO4)6Cl2:Eu or the like.

[0032] The phosphor may convert the excitation light into light specified by a spectrum having a peak wavelength in a wavelength region from, for example, 450 nm to 550 nm, that is, cyan light. In this case, the phosphor may include, for example, (Sr,Ba,Ca)5(PO4)3Cl:Eu,Sr4Al 14 O 25 :Eu or the like.

[0033] The phosphor may convert the excitation light into light specified by a spectrum having a peak wavelength in a wavelength region from, for example, 500 nm to 600 nm, that is, green light. In this case, the phosphor may include, for example, SrSi2(O,Cl)2N2:Eu, (Sr,Ba,Mg)2SiO4:Eu 2+ , or materials such as ZnS:Cu,Al, Zn2SiO4:Mn.

[0034] The phosphor may convert the excitation light into light specified by a spectrum having a peak wavelength in a wavelength region from, for example, 600 nm to 700 nm, that is, red light. In this case, the phosphor may include, for example, Y2O2S:Eu, Y2O3:Eu, SrCaClAlSiN3:Eu 2+ , CaAlSiN3:Eu, or CaAlSi(ON)3:Eu or the like.

[0035] The phosphor may convert excitation light into light specified by a spectrum having a peak wavelength within a wavelength range from, for example, 680 nm to 800 nm, that is, near-infrared light. The near-infrared light may include light in a wavelength range from 680 to 2500 nm. In this case, the phosphor may include, for example, a material such as 3Ga5O 12 :Cr or the like.

[0036] The combination of the types of phosphors contained in the wavelength conversion member 6 is not particularly limited. The phosphor is not limited to the above-described materials, and may include various other materials.

[0037] As described above, the excitation light incident from the light-emitting element 3 on the wavelength conversion member 6 is converted by the phosphor into light having different peak wavelengths. The peak wavelength of the converted light may be included in the visible light region. Depending on the combination of the phosphors included in the wavelength conversion member 6, the converted light may have a plurality of peak wavelengths. For example, when the phosphor includes a material that emits blue fluorescence, a material that emits blue-green fluorescence, and a material that emits green fluorescence, the converted light has the wavelengths of blue, blue-green, and green as peak wavelengths, respectively. When the phosphor includes only one type of material, the converted light has the peak wavelength of that material. The phosphor is not limited to these examples, and may include various combinations of materials. The color of the light emitted from the wavelength conversion member 6 is determined based on the type of material included in the phosphor. That is, the converted light may have various spectra.

[0038] The light-emitting device 10 according to the present embodiment can emit light having various spectra depending on the combination of the materials included in the phosphor. The light-emitting device 10 can emit, for example, light having a spectrum of direct sunlight from the sun, a spectrum of sunlight reaching a predetermined depth in the sea, a spectrum of light emitted by a candle flame, or light having a spectrum of light emitted by a firefly, or the like. In other words, the light-emitting device 10 can emit light having various colors. Further, the light-emitting device 10 can emit light having various color temperatures.

[0039] The wavelength conversion member 6 is located on the first surface 2A of the element substrate 2 and extends up to the side where the first surface 2A intersects with the side surface 2C in the plan view of the first surface 2A. The wavelength conversion member 6 is in contact with at least a part of the first surface 2A. At the portion of the first surface 2A where the reflection member 43 is located, the wavelength conversion member 6 is in contact with the first surface 2A via the reflection member 43. The wavelength conversion member 6 may be in direct contact with the first surface 2A of the element substrate 2 or may be in contact with the first surface 2A via the reflection member 43.

[0040] The wavelength conversion member 6 is in contact with at least the entire end portion 2D of the first surface 2A. The entire end portion 2D of the first surface 2A corresponds to the entire circumference of the side where the first surface 2A intersects with the side surface 2C. By the wavelength conversion member 6 being in contact with the end portion 2D of the first surface 2A, the excitation light reflected by the first surface 2A or the reflection member 43 necessarily passes through the wavelength conversion member 6. As a result, the conversion efficiency of the excitation light can be increased. Further, the wavelength conversion member 6 has a portion that extends outside at least a part of the end portion 2D of the first surface 2A in the plan view of the first surface 2A. By the wavelength conversion member 6 having a portion that extends outside the end portion 2D of the first surface 2A, the length of the excitation light passing through the wavelength conversion member 6 can be increased. As a result, the conversion efficiency of the excitation light can be increased.

[0041] The shape of the first surface 2A of the element substrate 2 may be rectangular. The shape of the first surface 2A is not limited to a rectangle and may be other polygons. The shape of the first surface 2A may be a figure having curved sides such as a circle or an ellipse. The wavelength conversion member 6 may extend outside each side of the first surface 2A of the element substrate 2. When the shape of the first surface 2A of the element substrate 2 is rectangular, the three-dimensional shape of the wavelength conversion member 6 may be a rectangular parallelepiped. Thereby, the length that the excitation light passes through the wavelength conversion member 6 can be increased. As a result, the conversion efficiency of the excitation light can be enhanced. Also, all of the outer edges of the wavelength conversion member 6 may be located outside each side of the element substrate 2. By this, when a mechanical external pressure is applied to the light-emitting device 10 from the outside, the possibility that the element substrate 2 is directly impacted and damaged can be reduced. Therefore, the occurrence of malfunction of the light-emitting device 10 can be reduced. Further, since the elastic modulus of the wavelength conversion member 6 is smaller than the elastic modulus of the element substrate 2, the possibility that the light-emitting device 10 is damaged against a mechanical external pressure from the outside can be reduced.

[0042] As shown in FIG. 4, the wavelength conversion member 6 includes an upper surface 6A facing the positive direction of the Z axis, a bottom surface 6B facing the negative direction of the Z axis, and side surfaces 6C intersecting the upper surface 6A and the bottom surface 6B. The side surfaces 6C are also referred to as wavelength conversion member side surfaces. The shape of the wavelength conversion member side surfaces may be convex toward the outside of the wavelength conversion member 6 in a cross-sectional view by at least one surface intersecting the first surface 2A of the element substrate 2. Since the shape of the wavelength conversion member side surfaces is convex, the distance that the excitation light passes through the wavelength conversion member 6 can be increased. As a result, the conversion efficiency of the excitation light can be enhanced.

[0043] The shapes on both sides of the portion where the wavelength conversion member 6 extends outward from the end 2D of the first surface 2A of the element substrate 2 may be different in a cross-sectional view of the element substrate 2. In other words, the shapes on both sides of the portion where the wavelength conversion member 6 extends outward from the end 2D of the first surface 2A of the element substrate 2 may be asymmetric with respect to the center line passing through the center of the wavelength conversion member 6 and extending in the stacking direction of the element substrate 2 and the wavelength conversion member 6 in a cross-sectional view by at least one plane intersecting the first surface 2A of the element substrate 2. Specifically, the lengths by which the wavelength conversion member 6 protrudes outward may be different. Also, the shapes of the side surfaces 6C of the wavelength conversion member 6 may be different.

[0044] In the light-emitting device 10, the surface roughness of the side surface 6C (wavelength conversion member side surface) of the wavelength conversion member 6 may be made larger than the surface roughness of the side surface 2C (substrate side surface) of the element substrate 2. When an external mechanical external pressure is applied to the light-emitting device 10, the possibility of cushioning the impact and being damaged can be reduced. As long as the measurement method and measurement standard of the surface roughness of the side surface 6C (wavelength conversion member side surface) of the wavelength conversion member 6 and the surface roughness of the side surface 2C (substrate side surface) of the element substrate 2 are the same, it may be appropriately selected according to the size, material, etc. in accordance with the standard by a contact method or a non-contact method. If it is a contact method, for example, a scanning method using a stylus can be used, and if it is a non-contact method, for example, an optical interference method, an image synthesis method by focus movement, a confocal method, etc. can be used.

[0045] The reflecting member 43 has a side surface 43C continuous from the side surface 2C of the element substrate 2. The side surface 43C of the reflecting member 43 is also referred to as the reflecting member side surface. The reflecting member side surface is inclined inward toward the wavelength conversion member 6 from the side where the first surface 2A of the element substrate 2 intersects the side surface 2C. In other words, the reflecting member side surface is inclined so as to enter the inside of the first surface 2A of the element substrate 2 as it moves away from the first surface 2A of the element substrate 2. By inclining the reflecting member side surface, the probability that the excitation light emitted from the bottom surface 6B of the wavelength conversion member 6 is reflected by the reflecting member side surface and enters the bottom surface 6B of the wavelength conversion member 6 increases. As a result, the conversion efficiency of the excitation light can be enhanced.

[0046] As shown in FIG. 5, the upper surface 6A of the wavelength conversion member 6 may be a concave surface. In other words, the wavelength conversion member 6 may have a concave surface that is recessed in a direction approaching the first surface 2A of the element substrate 2 in a portion that at least overlaps the light emitting element 3 in a plan view of the first surface 2A of the element substrate 2. By the upper surface 6A of the wavelength conversion member 6 being a concave surface, the direction of the illumination light emitted from the upper surface 6A of the wavelength conversion member 6 tends to converge to the center of the concave surface.

[0047] As shown in FIG. 6, a chamfered shape may be provided at the corner where the bottom surface 6B and the side surface 6C of the portion of the wavelength conversion member 6 that extends outward from the end portion 2D of the first surface 2A of the element substrate 2 intersect. In other words, the portion of the wavelength conversion member 6 that extends outward from the end portion 2D of the first surface 2A of the element substrate 2 may have a chamfered shape at the corner on the side closer to the first surface 2A of the element substrate 2 in a cross-sectional view by at least one surface intersecting the first surface 2A of the element substrate 2. The chamfered shape may be a C chamfer 6D as shown in FIG. 6 or an R chamfer. Thereby, it is possible to reduce the possibility that the portion of the wavelength conversion member 6 that extends outward from the element substrate 2 sags downward due to the weight of the wavelength conversion member itself.

[0048] As shown in FIGS. 7A and 7B, the chamfered shape of the corner of the wavelength conversion member 6 may differ depending on the direction of the cross-sectional view. As shown in FIG. 7A, in a cross-sectional view of the light emitting device 10 by a surface along the YZ plane, the wavelength conversion member 6 does not have a chamfered shape at the corner. On the other hand, as shown in FIG. 7B, in a cross-sectional view of the light emitting device 10 by a surface along the ZX plane, the wavelength conversion member 6 has a chamfered shape at the corner. Thereby, it is possible to maintain the balance between the effect of reducing the possibility that the portion of the wavelength conversion member 6 that extends outward from the element substrate 2 sags downward due to the weight of the wavelength conversion member itself and the effect of improving the light emission efficiency.

[0049] In a cross-sectional view taken along at least one plane intersecting the first surface 2A of the element substrate 2, the length of the portion of the wavelength conversion member 6 extending outward from the end 2D of the first surface 2A of the element substrate 2 may be 1% or more and 5% or less of the length of the element substrate 2 in the same cross-sectional view. By controlling the length in this way, the size of the light-emitting device 10 can be controlled. If it is 1% or more, when a mechanical external pressure is applied to the light-emitting device 10 from the outside, the risk that the element substrate 2 will be directly impacted and damaged can be reduced. Also, if it is 5% or less, the risk that the portion of the wavelength conversion member 6 extending outside the element substrate 2 will sag downward and deform due to the weight of the wavelength conversion member itself can be reduced. Note that the length referred to here means, for example, the maximum length of the portion of the wavelength conversion member 6 extending outside the end 2D of the element substrate 2 in the direction along the first surface 2A.

[0050] As shown in FIG. 1, in a plan view of the first surface 2A of the element substrate 2, the area of the light-emitting element 3 may be made wider than the area of the first electrode 41. By making the light-emitting element 3 wider than the first electrode 41, the light incident on the first electrode 41 with a low light reflectance can be reduced. As a result, the luminous efficiency of the light-emitting device 10 can be improved. In a plan view of the first surface 2A of the element substrate 2, the light-emitting element 3 may cover the entire first electrode 41. By covering the first electrode 41 with the light-emitting element 3, the light incident on the first electrode 41 with a low light reflectance can be reduced. As a result, the luminous efficiency of the light-emitting device 10 can be improved.

[0051] In a plan view of the first surface 2A of the element substrate 2, the area of the electronic component 7 may be made wider than the area of the second electrode 42. The electronic component 7 may cover the entire second electrode 42. The wiring connecting the first electrode 41 and the second electrode 42 may be covered by the light-emitting element 3 or the electronic component 7 at least in part, or may be exposed in a plan view of the first surface 2A of the element substrate 2.

[0052] As described above, in the light-emitting device 10 according to the present embodiment, the wavelength conversion member 6 can be configured in various shapes. By controlling the shape of the wavelength conversion member 6, the conversion efficiency of the excitation light in the wavelength conversion member 6 or the light-emitting efficiency of the light-emitting device 10 can be increased.

[0053] (Influence of dicing on the shape of the wavelength conversion member 6) The light-emitting device 10 according to the present embodiment is formed, for example, in a plurality on a wafer and manufactured by dividing the wafer by dicing. The shape of the side surface 6C of the wavelength conversion member 6 or the side surface 2C of the element substrate 2 can be controlled by the dicing conditions.

[0054] Dicing is performed by inserting a disk-shaped blade 80 while rotating it toward an object. As shown in FIG. 8A, the wavelength conversion member 6 can be dragged in the rotation direction of the dicing blade 80. After the blade 80 passes through the wavelength conversion member 6, the wavelength conversion member 6 that has been dragged in the rotation direction of the blade 80 returns to its original position. On the other hand, since the element substrate 2 has a larger elastic modulus than the wavelength conversion member 6, it is difficult to be dragged in the rotation direction of the blade 80. As a result, the width of the portion of the wavelength conversion member 6 cut by dicing can be narrower than the width of the portion of the element substrate 2 cut by dicing.

[0055] Alternatively, as shown in FIG. 8B, the dicing blade 80 can advance while pressing the wavelength conversion member 6 against the side surface of the blade 80 when cutting the wavelength conversion member 6. In this case, the wavelength conversion member 6 is compressed in the normal direction of the side surface of the blade 80. After the blade 80 passes through the wavelength conversion member 6, the wavelength conversion member 6 that has been pressed against the side surface of the blade 80 returns to its original position. On the other hand, since the element substrate 2 has a larger elastic modulus than the wavelength conversion member 6, it is difficult to be dragged in the rotation direction of the blade 80. As a result, the width of the portion of the wavelength conversion member 6 cut by dicing can be narrower than the width of the portion of the element substrate 2 cut by dicing.

[0056] As the width of the portion of the wavelength conversion member 6 cut by dicing becomes narrow, the wavelength conversion member 6 is formed to have a portion that extends outward from the end portion 2D of the first surface 2A of the element substrate 2. The difference between the width of the portion of the wavelength conversion member 6 cut by dicing and the width of the portion of the element substrate 2 cut by dicing can be controlled by the difference between the elastic modulus of the wavelength conversion member 6 and the elastic modulus of the element substrate 2. The length of the portion where the wavelength conversion member 6 extends outward from the end portion 2D of the first surface 2A of the element substrate 2 can be controlled by the difference between the elastic modulus of the wavelength conversion member 6 and the elastic modulus of the element substrate 2. Since the elastic modulus of the wavelength conversion member 6 is smaller than the elastic modulus of the element substrate 2, the wavelength conversion member 6 can be controlled to have a portion that extends outward from the end portion 2D of the first surface 2A of the element substrate 2.

[0057] The dicing conditions include the rotational speed of the dicing blade 80, the speed at which the blade 80 is inserted into the wavelength conversion member 6 and the element substrate 2, or the shape of the blade 80 and the like. The shape of the blade 80 is specified by, for example, the diameter, width, or surface roughness of the blade 80. The dicing conditions are also specified by which direction, the X-axis direction or the Y-axis direction, is cut first in order to cut out the light emitting device 10 from the wafer. By the dicing conditions, the shape of the side surface 2C of the wavelength conversion member 6, the shape of the side surface 43C of the reflection member 43, or the shape of the side surface 2C of the element substrate 2 can be controlled. For example, the surface roughness of the side surface 6C of the wavelength conversion member 6 or the surface roughness of the side surface 2C of the element substrate 2 can be controlled. Also, the convex shape of the side surface 6C of the wavelength conversion member 6 can be controlled. Also, the chamfered shape of the corner on the side of the wavelength conversion member 6 close to the first surface 2A of the element substrate 2 can be controlled.

[0058] (Configuration example of the lighting device 100) As shown in FIG. 9, an illumination device 100 according to an embodiment includes at least one light-emitting device 10, and emits the light emitted by the light-emitting device 10 as illumination light. When the illumination device 100 includes a plurality of light-emitting devices 10, the intensity of the light emitted by each light-emitting device 10 may be independently controlled or may be controlled in association. The spectra of the light emitted by each light-emitting device 10 may be the same or may be different from each other. The illumination device 100 may control the spectrum of the light synthesized from the light emitted by each light-emitting device 10 by controlling the intensity of the light emitted by each light-emitting device 10 in association. The light synthesized from the light emitted by each light-emitting device 10 is also referred to as synthesized light. The illumination device 100 may emit the synthesized light as illumination light. The illumination device 100 may select at least a part of the plurality of light-emitting devices 10 to emit illumination light.

[0059] The illumination device 100 may further include a mounting board 110 on which the light-emitting device 10 is mounted. The illumination device 100 may further include a housing 120 having a groove-shaped portion for accommodating the mounting board 110 and a pair of end plates 130 closing the end portions on the short side of the housing 120. The number of light-emitting devices 10 mounted on the mounting board 110 may be one or may be two or more. The light-emitting devices 10 may be mounted on the mounting board 110 so as to be arranged in a row, or may be mounted so as to be arranged in a grid pattern or a staggered pattern. The light-emitting devices 10 are not limited to these patterns and may be mounted on the mounting board 110 in various arrangement patterns.

[0060] The mounting board 110 may include a circuit board having a wiring pattern. The circuit board may include, for example, a printed board such as a rigid board, a flexible board, or a rigid-flexible board. The circuit board may include a drive circuit for controlling the light-emitting device 10.

[0061] The mounting board 110 has a function of dissipating the heat generated by the light-emitting device 10 to the outside. The mounting board 110 may be made of, for example, a metal material such as aluminum, copper, or stainless steel, an organic resin material, or a composite material including these.

[0062] The mounting plate 110 may have an elongated rectangular shape in plan view. The shape of the mounting plate 110 is not limited to this, and may be various other shapes.

[0063] The lighting device 100 may further include a lid portion 140 that seals the mounting plate 110 and the light emitting device 10 housed inside the housing 120. By being made of a light-transmissive material, the lid portion 140 may transmit the illumination light emitted by the light emitting device 10 to the outside of the lighting device 100. The lid portion 140 may be made of, for example, a resin material such as acrylic resin or glass. The lid portion 140 may have an elongated rectangular shape in plan view. The shape of the lid portion 140 is not limited to this, and may be various other shapes. The lighting device 100 may further include a sealing member between the lid portion 140 and the housing 120. By doing so, it becomes difficult for water, dust, etc. to enter the inside of the housing 120. As a result, the reliability of the lighting device 100 can be improved regardless of the environment in which the lighting device 100 is installed. The lighting device 100 may further include a moisture absorbent inside the housing 120.

[0064] The drawings for explaining the embodiments according to the present disclosure are schematic. The dimensional ratios, etc. on the drawings do not necessarily match the actual ones.

[0065] Although the embodiments according to the present disclosure have been described based on the drawings and examples, the present disclosure is not limited to the above-described embodiments. It should also be noted that those skilled in the art can make various modifications or alterations based on the present disclosure. Therefore, it should be noted that these modifications or alterations are included in the scope of the present disclosure. For example, the functions, etc. included in each component, etc. can be rearranged so as not to be logically contradictory, and a plurality of components, etc. can be combined into one or divided. In addition, changes can be made without departing from the spirit of the present disclosure.

[0066] In the present disclosure, descriptions such as "first" and "second" are identifiers for distinguishing the relevant configurations. The configurations distinguished by descriptions such as "first" and "second" in the present disclosure can have their numbers exchanged within the relevant configurations. For example, the first surface 2A can have the identifiers "first" and "second" exchanged with the second surface 23. The exchange of identifiers is performed simultaneously. The configurations are still distinguishable after the exchange of identifiers. The identifiers may be deleted. The configurations with the identifiers deleted are distinguished by reference signs. Based only on the descriptions of identifiers such as "first" and "second" in the present disclosure, the order of the relevant configurations should not be interpreted, nor should it be used as the basis for the existence of an identifier with a smaller number.

[0067] In the present disclosure, the X-axis, Y-axis, and Z-axis are provided for convenience of explanation and may be mutually interchanged. The configurations according to the present disclosure have been described using a rectangular coordinate system constituted by the X-axis, Y-axis, and Z-axis. The positional relationships of the respective configurations according to the present disclosure are not limited to being in an orthogonal relationship.

Description of Reference Signs

[0068] 10 Light-emitting device 2 Element substrate (2A: first surface, 2B: second surface, 2C: side surface, 2D: end portion) 3 Light-emitting element 6 Wavelength conversion member (6A: upper surface, 6B: bottom surface, 6C: side surface, 6D: chamfer C) 7 Electronic component 41 First electrode 42 Second electrode 43 Reflective member 44 Back surface electrode 45 Connection conductor path 80 Dicing blade 100 Lighting device (110: mounting board, 120: housing, 130: end plate, 140: lid portion)

Claims

1. a substrate having a first surface; a light emitting element located on the first surface of the substrate and emitting excitation light; a wavelength converting member in contact with at least the entire edge of the first surface of the substrate; Equipped with The wavelength conversion member has a portion that extends outward beyond at least a portion of an end of the first surface of the substrate in a plan view of the first surface of the substrate.

2. The first surface of the substrate has a rectangular shape, The light emitting device according to claim 1 , wherein the wavelength conversion member has a portion extending outward beyond each side of the first surface of the substrate.

3. The light emitting device according to claim 2 , wherein the entire outer edge of the wavelength conversion member is located outside an outer edge of the first surface of the substrate.

4. the substrate includes a reflector on the first surface, the reflector surrounding the light-emitting element; The light emitting device according to claim 1 , wherein the wavelength conversion member is in contact with an end portion of the first surface of the substrate via the reflecting member.

5. the reflecting member has a reflecting member side surface continuing from a side surface of the substrate, The light emitting device according to claim 4 , wherein the side surface of the reflecting member is inclined so as to move inwardly toward the first surface of the substrate as it becomes farther away from the first surface of the substrate.

6. The light emitting device according to claim 1 , wherein, in a cross-sectional view of the substrate taken along at least one plane intersecting the first surface of the substrate, the shapes of both sides of the portion of the wavelength conversion member extending outward from an end of the first surface of the substrate are different.

7. the substrate has a substrate side surface that intersects with the first surface, the wavelength conversion member has a wavelength conversion member side surface that intersects with a surface along the first surface of the substrate, The light emitting device according to claim 1 , wherein a surface roughness of the side surface of the substrate is smaller than a surface roughness of a side surface of the wavelength conversion member.

8. The light emitting device according to claim 1 , wherein the wavelength conversion member has a concave surface that is concave in a direction approaching the first surface of the substrate at least in a portion that overlaps with the light emitting element in a planar view of the first surface of the substrate.

9. 9. The light emitting device according to claim 1, wherein in a cross-sectional view of the substrate taken along at least one plane intersecting the first surface of the substrate, a portion of the wavelength conversion member extending outward from an end of the first surface of the substrate has an R-chamfered shape or a C-chamfered shape at a corner closer to the first surface of the substrate.

10. The light emitting device according to claim 1 , wherein the three-dimensional shape of the wavelength conversion member is a rectangular parallelepiped.

11. The light emitting device according to claim 1 , wherein the elastic modulus of the wavelength conversion member is smaller than the elastic modulus of the substrate.

12. 12. The light emitting device according to claim 1, wherein in a cross-sectional view of the substrate taken along at least one plane intersecting the first surface of the substrate, the length of a portion of the wavelength conversion member extending outward beyond the end of the first surface of the substrate is 1% or more and 5% or less of the length of the substrate in the cross-sectional view of the substrate.

13. the wavelength conversion member has a wavelength conversion member side surface that intersects with a surface along the first surface of the substrate, The light emitting device according to claim 1 , wherein a shape of a side surface of the wavelength conversion member in a cross-sectional view of the substrate taken along at least one plane intersecting with the first surface of the substrate is outwardly convex.

14. the substrate includes a first electrode on the first surface for supplying power to the light-emitting element; The light emitting device according to claim 1 , wherein an area of ​​the light emitting element is larger than an area of ​​the first electrode in a plan view of the first surface of the substrate.

15. The light emitting device according to claim 14 , wherein the light emitting element covers the entire first electrode in a plan view of the first surface of the substrate.

16. the substrate includes a second electrode on the first surface, the second electrode being electrically connected to the first electrode and supplying power to an electronic component other than the light-emitting element; The light emitting device according to claim 14 , wherein an area of ​​the electronic component is larger than an area of ​​the second electrode in a plan view of the first surface of the substrate.

17. A lighting device comprising: the light emitting device according to claim 1 ; and a mounting board on which the light emitting device is mounted.

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