Method for manufacturing a light-emitting device and a light-emitting device

Abstract

To provide a manufacturing method for a light-emitting device that is capable of increasing light extraction efficiency, and a light-emitting device manufactured by the method.SOLUTION: A method of manufacturing a light-emitting device includes the steps of applying a first member 301 on a substrate 10 on which one or more light emitting elements 20 are arranged so as to surround the light emitting elements 20 at a distance, and applying a second member 302 on the applied first member 301 so as to surround the light emitting elements 20 at a distance. The first member 301 and the second member 302 have light reflectivity, and have different light reflectances at the light emission peak wavelength of the light emitting elements 20.SELECTED DRAWING: Figure 4C

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a light-emitting device and a light-emitting device.

Background Art

[0002] A light-emitting device in which a light-emitting element is disposed on a substrate and sealed with a translucent resin is known. For example, Patent Documents 1 and 2 describe a light-emitting device in which a light-reflective dam material is provided in a ring shape to block a resin for sealing a light-emitting element or the like.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] An embodiment according to the present disclosure aims to provide a method for manufacturing a light-emitting device and a light-emitting device that can improve light extraction efficiency.

Means for Solving the Problems

[0005] A method for manufacturing a light-emitting device disclosed in an embodiment includes a step of applying a first member so as to surround the light-emitting element at a distance on a substrate on which one or more light-emitting elements are disposed, and a step of applying a second member so as to surround the light-emitting element at a distance on the applied first member. The first member and the second member have light reflectivity, and the light reflectivities at the emission peak wavelength of the light-emitting element are different.

[0006] Furthermore, the light-emitting device disclosed in the embodiment comprises one or more light-emitting elements, a substrate on which the light-emitting elements are arranged, a first frame on the substrate that surrounds the light-emitting elements at a distance from each other, and a second frame on the first frame that surrounds the light-emitting elements at a distance from each other, wherein the first frame and the second frame are light-reflective and have different light reflectances at the emission peak wavelength of the light-emitting elements. [Effects of the Invention]

[0007] According to the embodiments of this disclosure, the light extraction efficiency of the light-emitting device can be improved. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view illustrating a schematic of the light-emitting device according to the embodiment. [Figure 2A] This is a plan view illustrating a schematic of the light-emitting device according to the embodiment. [Figure 2B] Figure 2A is a schematic cross-sectional view along the IIB-IIB line. [Figure 3] This is a flowchart illustrating a method for manufacturing a light-emitting device according to an embodiment. [Figure 4A] This is a plan view illustrating a state in which light-emitting elements are arranged on a substrate in a method for manufacturing a light-emitting device according to an embodiment. [Figure 4B] This is a plan view illustrating the arrangement of the first member in the manufacturing method of the light-emitting device according to the embodiment. [Figure 4C] This is a plan view illustrating the arrangement of the second member in the manufacturing method of the light-emitting device according to the embodiment. [Figure 4D] This is a plan view illustrating the state in which a sealing member is arranged in a method for manufacturing a light-emitting device according to an embodiment. [Figure 5A] This is a cross-sectional view illustrating a state in which the first member is being coated in a method for manufacturing a light-emitting device according to an embodiment. [Figure 5B] This is a cross-sectional view illustrating the state in which the second member is being applied in the manufacturing method of the light-emitting device according to the embodiment. [Figure 6A]In the first modification of the method for manufacturing a light-emitting device, it is a cross-sectional view illustrating a state in which the first member is being applied. [Figure 6B] In the first modification of the method for manufacturing a light-emitting device, it is a cross-sectional view illustrating a state in which the second member is being applied. [Figure 7] It is a flowchart illustrating a second modification of the method for manufacturing a light-emitting device. [Figure 8A] In the second modification of the method for manufacturing a light-emitting device, it is a cross-sectional view illustrating a state in which the first member is being applied. [Figure 8B] In the second modification of the method for manufacturing a light-emitting device, it is a cross-sectional view illustrating a state in which the third member is being applied. [Figure 8C] In the second modification of the method for manufacturing a light-emitting device, it is a cross-sectional view illustrating a state in which the second member is being applied. [Figure 9] It is a schematic of the light-emitting device according to the embodiment, and it is a plan view illustrating a case where a plurality of light-emitting elements are provided.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments according to the present disclosure will be described. However, the embodiments shown below are examples of a light-emitting device and a method for manufacturing a light-emitting device for embodying the technical idea according to the present disclosure, and are not limited thereto. In addition, dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments are not intended to limit the scope of the present invention only thereto, but are merely examples, unless otherwise specified. Note that the sizes and positional relationships of the members shown in each drawing may be exaggerated or simplified for clarity of explanation. In addition, in the embodiments, "covering" includes not only the case of directly contacting but also the case of indirectly covering, for example, via other members.

[0010] The light-emitting device 1 according to the embodiment will be described with reference to the drawings. FIG. 1 is a perspective view illustrating an overview of the light-emitting device 1. FIG. 2A is a plan view illustrating an overview of the light-emitting device 1. FIG. 2B is a schematic cross-sectional view taken along line IIB-IIB of FIG. 2A.

[0011] The light-emitting device 1 is a COB (Chip On Board) type light-emitting device in which the light-emitting element 20 is directly disposed on the substrate 10 having the electrode terminal 13. The light-emitting device 1 includes one or a plurality (one in FIG. 2A) of light-emitting elements 20, a substrate 10 on which the light-emitting elements 20 are disposed, a first frame 31 that surrounds the light-emitting elements 20 while being spaced apart on the substrate 10, and a second frame 32 that surrounds the light-emitting elements 20 while being spaced apart on the first frame 31. The first frame 31 and the second frame 32 have light reflectivity and different light reflectivities at the emission peak wavelength of the light-emitting element 20. As an example, in the light-emitting device 1, the first frame 31 and the second frame 32 constitute a frame body 30, and a sealing member 40 that covers the light-emitting elements 20 is provided inside the frame body 30. Hereinafter, each component of the light-emitting device 1 will be described.

[0012] (Substrate) The substrate 10 serves as a base of the light-emitting device 1 and is a member on which the light-emitting elements 20 are disposed. The substrate 10 has an electrode terminal 13 connected to an external power source and a wiring 12 continuous from the electrode terminal 13 on the upper surface of a plate-like base material 11. The base material 11 is formed in a rectangular shape in a plan view as an example. The base material 11 may be a non-rectangular polygon or a circular shape. The base material 11 can be made of an insulating material such as resin such as epoxy, glass epoxy, bismaleimide triazine or polyimide, or ceramics or glass.

[0013] Note that a light reflection member may be disposed on the upper surface of the base material 11 in order to enhance the light reflectivity on the surface. The light reflection member is preferably white, and preferably contains a white pigment such as titanium oxide or magnesium oxide in the base material. Examples of the base material of the light reflection member include resin or modified resin such as silicone. Further, the light reflection member may further contain particles of a light-reflective substance such as silicon oxide or aluminum oxide as a filler.

[0014] As an example, the wiring 12 is formed in a semi-circular shape, continuously extending from the positive and negative electrode terminals 13, so as to surround the circular area where the light-emitting element 20 is placed. The electrode terminals 13 are arranged in a rectangular shape at opposite corners of the base material 11, so as to cover an area wider than the wiring 12. The wiring 12 is connected to the light-emitting element 20 by bonding wires 14. The light-emitting element 20 is mounted face up on the substrate 10. Alternatively, the light-emitting element 20 can be mounted on the substrate 10 by flip-chip mounting without using bonding wires 14. In this case, the wiring 12 may be formed to match the position of the element electrodes of the light-emitting element 20. The materials for the wiring 12 and electrode terminals 13 can be metals such as copper, iron, nickel, tungsten, chromium, aluminum, titanium, palladium, rhodium, silver, platinum, gold, or alloys thereof. The wiring 12 and electrode terminals 13 may be formed from these materials in a single layer or multiple layers, and may also be plated. The bonding wire 14 is a linear member made of, for example, gold, copper, silver, platinum, aluminum, or an alloy thereof.

[0015] (light-emitting element) The light-emitting element 20 is a semiconductor element that emits light when an electric current flows through it, and can be, for example, an LED chip. The light-emitting element 20 comprises at least a semiconductor laminate. The semiconductor laminate includes, for example, a support substrate such as sapphire or gallium nitride, an n-type semiconductor layer and a p-type semiconductor layer disposed on the support substrate, and a light-emitting layer sandwiched between them. The semiconductor laminate may also be one from which the support substrate has been removed. Furthermore, the structure of the light-emitting layer may be a structure with a single active layer, such as a double heterostructure or a single quantum well structure (SQW), or a structure with a group of active layers, such as a multiple quantum well structure (MQW). The light-emitting layer is capable of emitting visible light or ultraviolet light. As visible light, the light-emitting layer is capable of emitting from blue to red. An example of a semiconductor laminate containing such a light-emitting layer is In x Al y Ga 1-x-yIt can include N(0≦x, 0≦y, x+y≦1).

[0016] A semiconductor laminate may include at least one light-emitting layer capable of emitting the above-described colors. For example, a semiconductor laminate may have a structure that includes one or more light-emitting layers between an n-type semiconductor layer and a p-type semiconductor layer, or it may have a structure in which an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer are repeated multiple times. When a semiconductor laminate includes multiple light-emitting layers, it may include light-emitting layers with different colors, or it may include light-emitting layers with the same color. The same color means within a range that can be considered the same color for practical use, for example, there may be a variation of a few nanometers in the main wavelength. Combinations of light-emitting colors can be selected as appropriate, and examples include 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. In addition, a protective element 15 may be provided between the positive and negative terminal wiring 12 in conjunction with the light-emitting element 20. The protective element 15 can be, for example, a Zener diode, a varistor, a resistor, or a capacitor. The height from the top surface of the substrate 10 to the top surface of the light-emitting element 20 is preferably 150 μm or more and 400 μm or less, and particularly preferably 200 μm or more and 350 μm or less.

[0017] (Frame) The frame 30 is a component that forms a frame that demarcates the light-emitting area in the light-emitting device 1. It is preferable that the frame 30 is light-reflective. The frame 30 surrounds the light-emitting element 20 on the substrate 10, keeping it at a distance. The frame 30 is wider than the wiring 12 and is formed in a circular shape to cover the wiring 12, surrounding the area where the light-emitting element 20 is placed. The frame 30 may be a polygonal shape such as an ellipse, square, pentagon, or hexagon to match the area where the light-emitting element 20 is placed. The frame 30 is preferably flared outwards towards the substrate 10 in cross-sectional view. The frame 30 is formed such that its height from the top surface of the substrate 10 is at least higher than the top surface of the light-emitting element 20. The height of the frame 30 from the top surface of the substrate 10 is preferably 300 μm or more and 1200 μm or less, and particularly preferably 400 μm or more and 1000 μm or less. The frame 30 comprises a first frame 31 that covers the wiring 12 and a second frame 32 that is provided on the first frame 31.

[0018] (Slot 1) The first frame 31 is a component located on the substrate 10 side of the frame body 30. The first frame 31 forms the flared base portion of the frame body 30. Preferably, the first frame 31 has an inclined surface 35 that slopes downward toward the light-emitting element 20 at an angle of 10 to 45 degrees with respect to the upper surface of the substrate 10, and is particularly preferably 15 to 40 degrees. The width of the first frame 31 in plan view is preferably 700 μm to 1450 μm, and is particularly preferably 1000 μm to 1300 μm. This first frame 31 is light-reflective. The first frame 31 has a different light reflectance at the emission peak wavelength of the light-emitting element 20 compared to the second frame 32. Here, a difference in light reflectance means that the light reflectance at the emission peak wavelength of the light-emitting element 20 differs by at least 3%, preferably by 5% or more, and more preferably by 8% or more. The light reflectance of the first frame 31 at the emission peak wavelength of the light-emitting element 20 is 90% or more, preferably 95% or more, and more preferably 97% or more. On the other hand, the light reflectance of the second frame 32 at the emission peak wavelength of the light-emitting element 20 differs from that of the first frame 31 by at least 3%, and is 90% or more, preferably 95% or more, and more preferably 97% or more.

[0019] (Second slot) The second frame 32 is a member located on the upper side of the frame body 30. The upper end of the second frame 32 forms the upper end of the frame body 30. In plan view, the width of the second frame 32 is narrower than that of the first frame 31, preferably between 400 μm and 1400 μm, and particularly preferably between 600 μm and 1200 μm. In cross-sectional view, the shape of the second frame 32 is elliptical or circular. The lower surface of the second frame 32 may be in contact with the substrate 10, or a part of the lower surface may be flat.

[0020] The materials of the first frame 31 and the second frame 32 can be light-reflective and insulating resins or ceramics. The first frame 31 and the second frame 32 may have the same base material. If the base material of the first frame 31 and the second frame 32 is resin, particles of a light-reflective substance may be dispersed as a filler in the resin base material. If the base material is ceramic, it may be a ceramic material containing a light-reflective substance, and different types of light-reflective substances may be included. The first frame 31 and the second frame 32 may both be made of resin, both be made of ceramics, or one may be made of resin and the other of ceramics. When both are made of resin or ceramics, it is preferable that the base material is the same from the viewpoint of adhesion and thermal expansion coefficient. The resin base material can be, for example, dimethyl silicone resin, phenyl silicone resin, epoxy resin, etc., and it is preferable to use dimethyl silicone resin, which has high heat resistance. The ceramic base material can be boron nitride, aluminum oxide, aluminum nitride, silicon nitride, silicon dioxide, zirconium oxide, etc.

[0021] Light-reflecting materials that can be used include titanium dioxide, silicon dioxide, zirconium oxide, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, mullite, etc. If the light-emitting color of the light-emitting element 20 is ultraviolet light, fillers other than titanium dioxide, such as potassium titanate, zirconium oxide, yttrium oxide, etc., can be used. The light reflectivity of ceramics can be adjusted by the type of light-reflecting material, while the light reflectivity of resins can be adjusted by the type and amount of filler. Note that increasing the filler content tends to increase the viscosity of the resin.

[0022] The first frame 31 and the second frame 32 have different light reflectances at the emission peak wavelength of the light-emitting element 20. That is, the light reflectance of the first frame 31 at the emission peak wavelength of the light-emitting element 20 can be made greater than or less than the light reflectance of the second frame 32. By increasing the light reflectance of the first frame 31, deterioration of the first frame 31 and the second frame 32 due to heat and light can be suppressed. From this viewpoint, it is preferable that the light reflectance of the first frame 31 is greater than that of the second frame 32. On the other hand, from the viewpoint of forming the inclined surface 35, it may be easier to adjust the shape if the light reflectance is not increased. In such cases, the light reflectance of the first frame 31 can be reduced and the light reflectance of the second frame 32 can be increased.

[0023] The light-emitting device 1 can be constructed using a first frame 31 and a second frame 32 to form a frame body 30. The frame body 30 is required to have high light reflectivity while ensuring a predetermined width and height from the substrate 10. However, in the formation of the frame body 30, there is sometimes a trade-off between light reflectivity and ease of shape adjustment. In the light-emitting device 1, the first frame 31 and the second frame 32, which have different light reflectivity, mutually complement each other in terms of light reflectivity and ease of shape adjustment in the frame body 30, thereby achieving both shape and light reflectivity in the frame body 30 and improving light extraction efficiency.

[0024] In the light-emitting device 1, it is preferable that the first frame 31 has an inclined surface 35 that slopes downward toward the light-emitting element 20 at an angle of 10 degrees or more and 45 degrees or less with respect to the upper surface of the substrate 10. As a result, the light-emitting device 1 can reflect light from the side of the light-emitting element 20 upward, thereby extracting light from the light-emitting surface more efficiently.

[0025] In the light-emitting device 1, it is preferable that the first frame 31 and the second frame 32 are made of the same resin material. This improves the adhesion between the first frame 31 and the second frame 32, thereby increasing the reliability of the frame 30. However, even if the base materials of the first frame 31 and the second frame 32 are the same, the light reflectances of the first frame 31 and the second frame 32 may differ. If the second frame 32 is applied before the first frame 31 is cured or solidified, an interface between the first frame 31 and the second frame 32 may not be formed.

[0026] In the light-emitting device 1, it is preferable that the first frame 31 is made of ceramics and the second frame 32 is made of resin. This allows the light-emitting device 1 to place ceramics with high light reflectivity and heat resistance at a position close to the light-emitting element 20, thereby improving light extraction efficiency and reliability. Furthermore, by including more filler in the resin of the second frame 32 than in the ceramics of the first frame 31, the light reflectivity can be increased and the viscosity can be increased to ensure the height of the frame 30. In addition, even if voids occur in the ceramics of the first frame 31, the resin of the second frame 32 can fill the voids, thereby reducing cracking and chipping caused by voids.

[0027] In the light-emitting device 1, it is preferable that the first frame 31 is made of resin and the second frame 32 is made of ceramics. This allows the light-emitting device 1 to improve light extraction efficiency by forming the first frame 31 into a desired shape using resin, which is easy to adjust in shape, and forming the second frame 32 with ceramics, which has high light reflectivity. Furthermore, if a ceramic material that easily leaches alkaline components is used for the second frame 32, corrosion of the wiring 12 can be suppressed because the second frame 32 does not directly come into contact with the wiring 12. However, it is preferable that the resin of the first frame 31 is a material that does not permeate or does not easily permeate alkaline components.

[0028] Preferably, the light reflectance of the first frame 31 at the emission peak wavelength of the light-emitting element 20 is greater than the light reflectance of the second frame 32. This allows the light-emitting device 1 to increase the light reflectance of the first frame 31, which is located below and near the light-emitting element 20, thereby effectively suppressing deterioration of the first frame 31 and the second frame 32 due to heat and light.

[0029] (Sealing member) The sealing member 40 is a member that forms the light-emitting region of the light-emitting device 1. The upper surface of the sealing member 40 forms the light-emitting surface of the light-emitting device 1. The sealing member 40 also covers and protects the light-emitting element 20 and the bonding wire 14. The sealing member 40 is filled inside the frame 30. The height of the peripheral edge of the sealing member 40 can be less than or equal to the height of the upper end of the frame 30, and in this case, it is the height of the upper end of the frame 30. Preferably, the sealing member 40 has a central height that is higher than the peripheral edge and a convex shape in cross-section. This allows the light-emitting device 1 to increase its brightness when viewed from above. The sealing member 40 preferably has insulating and light-transmitting properties, as well as excellent weather resistance and light resistance. The material of the sealing member 40 can be, for example, a resin based on silicone, epoxy, phenol, polycarbonate, acrylic, etc. The sealing member 40 may also contain wavelength-converting substances or light-reflecting substances as fillers.

[0030] The wavelength-converting material absorbs at least a portion of the primary light emitted by the light-emitting element 20 and emits secondary light of a different wavelength than the primary light. For example, the primary light emitted by the light-emitting element 20 and the secondary light emitted by the wavelength-converting material can be mixed to obtain white light. It is preferable that the wavelength-converting material is concentrated near the light-emitting element 20, which can increase the efficiency of wavelength conversion. The light-reflective material can diffuse the light emitted by the light-emitting element 20 or the wavelength-converting material, thereby achieving uniform brightness on the light-emitting surface. It is preferable that the light-reflective material is dispersed in the sealing member 40. The sealing member 40 may be made by laminating materials that differ in the presence or absence, or type, of the wavelength-converting material or light-reflecting material contained within.

[0031] [Manufacturing method for light-emitting devices] Next, a method for manufacturing the light-emitting device according to the embodiment will be described with reference to Figures 3 to 5B. Figure 3 is a flowchart illustrating a method for manufacturing the light-emitting device. Figure 4A is a plan view illustrating a schematic state in which the light-emitting element 20 is arranged on the substrate 10. Figure 4B is a plan view illustrating a schematic state in which the first member 301 is arranged. Figure 4C is a plan view illustrating a schematic state in which the second member 302 is arranged. Figure 4D is a plan view illustrating a schematic state in which the sealing member 40 is arranged. Figure 5A is a cross-sectional view illustrating a schematic state in which the first member 301 is being applied. Figure 5B is a cross-sectional view illustrating a schematic state in which the second member 302 is being applied.

[0032] The method for manufacturing the light-emitting device includes a step S21 of coating a first member 301 on a substrate 10 on which one or more light-emitting elements 20 are arranged, so as to surround the light-emitting elements 20 at a distance, and a step S22 of coating a second member 302 on the coated first member 301 so as to surround the light-emitting elements 20 at a distance, wherein the first member 301 and the second member 302 have light reflectivity and have different light reflectances at the emission peak wavelength of the light-emitting elements 20. The steps of applying the first member 301 (S21) and applying the second member 302 (S22) are combined to form the application step (S20). The first member 301 and the second member 302 are combined to form the frame member 300. The method for manufacturing the light-emitting device further includes a preparation step S10 performed before the coating step S20 to prepare the substrate 10 on which the light-emitting element 20 is placed, a curing step S30 performed during or after the coating step S20 to harden the frame member 300 to form the frame body 30, and a sealing step S40 performed after the curing step S30 to form a sealing member 40 inside the frame body 30. The steps of the method for manufacturing the light-emitting device will be described below. Here, we will refer to it as curing and curing step, but it may also be referred to as solidification and solidification step. Also, curing may be referred to as solidification, and vice versa, but the meaning is that a liquid is turned into a solid.

[0033] (preparation process) Preparation step S10 is a step of preparing the substrate 10 on which the light-emitting element 20 is placed. First, positive electrode and negative electrode wiring 12 and electrode terminals 13 are formed on the upper surface of the substrate 11, for example by etching. The wiring 12 is formed so as to surround the area on which the light-emitting element 20 will be placed. A light-reflecting member may be provided in this area before placing the light-emitting element 20. It is preferable to place the light-emitting element 20 in the center of this area. The light-emitting element 20 is bonded to the substrate 11 or the light-reflecting member by an adhesive member. The light-emitting element 20 is positioned so that the side with the pair of element electrodes is the upper surface, and the pair of element electrodes are connected to the wiring 12 by bonding wires 14. In addition, a protective element 15 is provided between the positive and negative electrode wiring 12.

[0034] (Coating process) The coating step S20 is a step of coating the first member 301 and the second member 302. The coating step S20 consists of a step S21 in which the first member 301 is coated on the substrate 10 so as to surround the light-emitting element 20 at a distance, and a step S22 in which the second member 302 is coated on the coated first member 301 so as to surround the light-emitting element 20 at a distance. The coating step S20 can be performed by coating the material of the frame member 300, which is fluid before curing or solidification, with a dispenser nozzle. Step S21, which involves applying the first component 301, is performed by advancing the first nozzle 81 of the dispenser while dispensing the material 301A of the first component from the first nozzle 81. The first nozzle 81 can move in a clockwise or counterclockwise direction around the area where the light-emitting element 20 is placed. Here, it is moved in a counterclockwise direction D1 along the wiring 12. Figure 5A illustrates the state after the first nozzle 81 has passed.

[0035] Step S22, in which the second component 302 is applied, is performed by advancing the second nozzle 82 of the dispenser while discharging the material 302A of the second component from the second nozzle 82. The second nozzle 82 can move in a clockwise or counterclockwise direction around the area where the light-emitting element 20 is placed, similar to the first nozzle 81. Here, it is moved in a counterclockwise direction D1 along the first component 301. Figure 5B illustrates the state after the second nozzle 82 has passed. Note that the first nozzle 81 and the second nozzle 82 may sometimes be described as nozzle 80.

[0036] The first member 301 is applied after the second member 302 is placed so that it forms a flared shape. The shape of the first member 301 can be adjusted by viscosity. Here, the viscosity is adjusted so that an inclined surface 350 is formed on the light-emitting element 20 side, which forms an angle of 10 degrees to 45 degrees with the upper surface of the substrate 10. Note that lower viscosity tends to result in a gentler slope of the inclined surface 350. Furthermore, it is preferable to keep the wettability of the first member 301 to the substrate 11 and wiring 12 within a predetermined range to prevent the first member 301 from spreading laterally more than necessary. In other words, even if the first member 301 does not form a flared shape when applied to the substrate 10, applying the second member 302 on top of the first member 301 may cause the first member 301 to spread laterally and form a flared shape. This suppresses the lateral spreading of the first member 301 and allows the height of the frame member 300 to be increased. For example, the angle of the inclined surface 350A with respect to the substrate 10 when the first member 301 is applied may be between 70 degrees and 150 degrees.

[0037] Furthermore, the width of the first member 301 after the second member 302 has been placed is preferably 700 μm to 1450 μm, and particularly preferably 1000 μm to 1300 μm. The height of the first member 301 before coating the second member 302 and before processing such as pressing is preferably 200 μm to 1000 μm, and particularly preferably 300 μm to 800 μm. The inner diameter of the first nozzle 81 is preferably 100 μm to 600 μm, and particularly preferably 200 μm to 450 μm. The first member 301 is coated by rotating the first nozzle 81 once or multiple times.

[0038] On the other hand, the second member 302 is applied with priority given to increasing its height. The shape of the second member 302 can also be adjusted by viscosity. It is preferable that the viscosity of the second member 302 is higher than that of the first member 301. The height of the upper end of the second member 302 is preferably at least twice the height of the upper surface of the light-emitting element 20, with reference to the upper surface of the substrate 10. The second member 302 can be coated in multiple layers by passing the second nozzle 82 around multiple times. During the rotation of the nozzle 80, it is preferable to stop the material discharge so that the end point of the rotation does not overlap with the starting point, but rather is continuous. This helps to suppress changes in the height of the frame member 300.

[0039] The frame member 300 is made of a light-reflective material. The first member 301 and the second member 302 of the frame member 300 have different light reflectances at the emission peak wavelength of the light-emitting element 20. It is preferable that the frame member 300 has a high light reflectance. The frame member 300 can be made of resin or ceramics. In the case of resin, the material can be made fluid depending on the base material before hardening. In the case of ceramics, ceramic particles can be dispersed in a dispersant such as water to make the material fluid before solidification.

[0040] Ceramics can achieve a higher light reflectivity compared to resins. However, before solidification, ceramics have a higher viscosity than resins, and the addition of light-reflective substances further increases the viscosity, which can make it difficult to form the frame member 300 by coating. Furthermore, the addition of light-reflective substances can cause a sudden increase in viscosity, making viscosity control difficult. Ceramics also have the advantage of higher heat resistance compared to resins. Resins have a wide range of viscosity adjustment, and their viscosity can be changed gradually, making them easy to adjust. The viscosity of a resin can be adjusted, for example, by the filler content, and increasing the filler content tends to increase the viscosity. The light reflectivity of a resin can be increased by increasing the content of light-reflective fillers, and even when the filler content is increased, the viscosity can be kept within a range suitable for forming the frame member 300 by coating.

[0041] The frame member 300 can be made of resin for both the first member 301 and the second member 302, and the base material can be the same resin. Furthermore, both the first member 301 and the second member 302 can be made of ceramics, and by making both of them ceramics, the light reflectivity can be increased. Furthermore, the frame member 300 can be made of a ceramic first member 301 and a resin second member 302, or the first member 301 can be made of a resin and the second member 302 can be made of a ceramic.

[0042] It is preferable to coat the second member 302 such that its widthwise center is further from the light-emitting element 20 than the widthwise center of the first member 301. For example, the target line C2 can be set outside the widthwise center line C1 of the coated first member 301, and the coating can be performed so that the center of the second nozzle 82 passes through the target line C2. The width of the second member 302 is preferably 400 μm to 1400 μm, and particularly preferably 600 μm to 1200 μm. The height of the second member 302 from the top surface of the substrate 10 is preferably 300 μm to 1200 μm, and particularly preferably 400 μm to 1000 μm. The inner diameter of the second nozzle 82 is preferably 100 μm to 600 μm, and particularly preferably 200 μm to 450 μm.

[0043] Furthermore, the width of the frame member 300 can also be adjusted by the discharge rate per unit time from the nozzle 80 and the speed of the nozzle 80's movement. By increasing the discharge rate per unit time or slowing down the movement of the nozzle 80, the frame member 300 can be coated with a wider width. When changing the direction of the nozzle 80's movement to create a corner in a plan view, for example, by reducing the discharge rate near the corner without changing the speed of movement, the change in the width of the frame member 300 can be suppressed.

[0044] (hardening process) The curing process S30 is a process in which the frame member 300 is cured to form the frame body 30. Here, "curing using resin" is described, but "solidification using ceramics" may also be used. The curing process S30 consists of a first curing process S31 and a second curing process S32. The first curing process S31 is performed before the process S22 in which the second member 302 is applied. The second curing process S32 is performed after the process S22 in which the second member 302 is applied. The first curing step S31 can be omitted. That is, the second member 302 may be applied after the first member 301 has been cured by the first curing step S31, or the first curing step S31 may be omitted and the second member 302 may be applied on the first member 301 before curing. If the first curing step S31 is omitted, both the first member 301 and the second member 302 can be cured by the second curing step S32. However, if the first member 301 is made of ceramics, it is preferable to perform the first curing step S31 because the volume reduction due to solidification may be large.

[0045] The resin is cured by a predetermined method, such as heating or irradiating it with ultraviolet light. The ceramics are preferably solidified using a pressure oven. Solidifying under pressure reduces the voids within the ceramics, improving light reflectivity.

[0046] (Sealing process) The sealing step S40 is a step in which a sealing member 40 is formed inside the frame 30. The sealing member 40 is formed by placing the uncured sealing member 40 material and curing it. The material of the sealing member 40 can be, for example, a thermosetting resin, and may contain wavelength conversion material or light reflecting material as a filler. The sealing member 40 is formed inside the frame 30 so as to cover at least the upper surface of the substrate 10, the light-emitting element 20, the bonding wire 14, and the first frame 31. Preferably, the sealing member 40 is formed so that the height of the central part is higher than the peripheral part and has a convex shape in cross-section.

[0047] The method for manufacturing the light-emitting device involves combining a first member 301 and a second member 302 having different light reflectivity, thereby achieving a balance between the light reflectivity of the frame member 300 and the adjustment of its shape by coating, and enabling the manufacture of a light-emitting device with improved light extraction efficiency.

[0048] In the manufacturing method of the light-emitting device, it is preferable to make the viscosity of the second member 302 higher than that of the first member 301. This allows the manufacturing method of the light-emitting device to apply the first member 301 in a flared shape and to ensure the height of the frame member 300 with the second member 302.

[0049] In the manufacturing method of the light-emitting device, it is preferable that the first member 301 and the second member 302 are made of the same resin. This makes it easier to adjust the viscosity of the first member 301 and the second member 302 and apply them to the desired shape. Furthermore, by using the same base material, the adhesion between the first member 301 and the second member 302 can be improved.

[0050] In the manufacturing method of the light-emitting device, it is preferable that the first component 301 is made of ceramics and the second component 302 is made of resin. This allows for a higher light reflectivity of the first component 301, and the second component 302 is easier to coat by increasing its viscosity and height. By increasing the heat resistance of the first component 301, which is located near the light-emitting element 20, the reliability of the light-emitting device can be improved. The viscosity of the second component 302 can be increased by increasing the content of the light-reflective filler, and the light reflectivity can also be increased. Furthermore, the light reflectivity of the ceramics can be further increased by solidifying them to improve the packing capacity of the light-reflective material.

[0051] In the manufacturing method of the light-emitting device, it is preferable that the first component 301 is made of resin and the second component 302 is made of ceramics. This allows the first component 301 to be easily applied to a desired shape by adjusting its viscosity. Furthermore, the second component 302 can increase the light reflectivity. The manufacturing method for the light-emitting device combines the advantages of resin in shape adjustment and the advantages of ceramics in light reflectivity to form a frame 30 with a desired shape and high light reflectivity, thereby enabling the production of a light-emitting device with improved light extraction efficiency.

[0052] In the manufacturing method of the light-emitting device, step S22, which involves applying the second member 302, preferably involves applying the second member 302 in multiple layers. This prevents the width of the second member 302 from increasing, allowing the second member 302 to be coated to achieve the desired height.

[0053] In the manufacturing method of the light-emitting device, step S22, in which the second member 302 is applied, is preferably such that the center of the second member 302 in the width direction is located further from the light-emitting element 20 than the center of the first member 301 in the width direction. This makes it possible to suppress the reduction in the inner diameter of the first member 301 caused by applying the second member 302. In addition, it is possible to smooth the side surface of the inner circumference of the frame member 300.

[0054] (Variations in the manufacturing method) Next, a first modified example of the method for manufacturing the light-emitting device according to the embodiment will be described. The first modified example includes a step S21 of applying a first member 301 to a substrate 10 on which one or more light-emitting elements 20 are arranged, so as to surround the light-emitting elements 20 at a distance from each other, and a step S22 of applying a second member 302 to the applied first member 301 so as to surround the light-emitting elements 20 at a distance from each other. In the step S21 of applying the first member 301, the first member 301 is dispensed from a nozzle and applied so as to be at a height greater than or equal to the position of the nozzle's discharge port in a direction perpendicular to the substrate 10.

[0055] In the first modified example, the position of the first nozzle 81 in step S21, in which the first member 301 is applied, differs from that of the manufacturing method according to the embodiment. Also, the first nozzle 81 may be used in step S22, in which the second member 302 is applied. Other points are the same as those of the manufacturing method according to the embodiment. Figure 6A is a cross-sectional view illustrating a schematic state in which the first member 301 is applied. Figure 6B is a cross-sectional view illustrating a schematic state in which the second member 302 is applied.

[0056] In step S21 of applying the first member 301 in the first modified example, the first nozzle 81 is brought close to the substrate 10 and the material 301A is applied by pressing it against the substrate 10. In order to apply the material 301A by pressing it against the substrate 10, in addition to bringing the first nozzle 81 close to the substrate 10, the amount of material 301A discharged per unit time can be increased and the movement of the first nozzle 81 can be slowed. The first member 301 is applied so as to spread out on the substrate 10. The upper end of the first member 301 is raised to a height greater than or equal to the discharge port 81A of the first nozzle 81. It is preferable that the first member 301 is not in contact with the side surface 81B of the first nozzle 81. The materials of the first member 301 and the second member 302 are the same as those used in the manufacturing method according to the embodiment. However, in the first modified example, the viscosities of the first member 301 and the second member 302 may be the same or different. The first member 301 can be applied in a flared shape even without lowering its viscosity. Also, the light reflectance of the light-emitting element 20 of the first member 301 and the second member 302 at the emission peak wavelength may be the same or different.

[0057] Alternatively, the base material of the first member 301 and the second member 302 may be the same, and in step S22 of coating the second member 302, the first nozzle 81 used in step S21 of coating the first member 301 may be moved away from the first member 301 and moved to a height where the second nozzle 82 is expected to discharge the second member 302, and the second member 302 may be coated using the first nozzle 81. Furthermore, the material 301A of the first member 301 may be used as is as the material 302A of the second member 302.

[0058] In the first modified method for manufacturing the light-emitting device, the first member 301 can be coated into a flared shape even if it has a higher viscosity compared to the case where the shape is adjusted by viscosity. For example, the viscosities of the first member 301 and the second member 302 may be similar, which broadens the range of material selection and makes it possible to manufacture a light-emitting device with improved light extraction efficiency. Furthermore, in the first modified example, the manufacturing process can be simplified by using the same nozzle in the step S21 for applying the first member 301 and the step S22 for applying the second member 302.

[0059] Next, a second modified example of the method for manufacturing the light-emitting device according to the embodiment will be described. The second modified example further includes a step S23 of applying a third member 303 to the inner side surface of the first member 301 so as to form an inclined surface 350A that slopes downward toward the light-emitting element 20 at an angle of 10 degrees or more and 45 degrees or less with respect to the upper surface of the substrate 10, wherein the third member 303 has light reflectivity and its light reflectance at the emission peak wavelength of the light-emitting element 20 is different from that of the second member 302.

[0060] In the second modification, compared to the manufacturing method of the light-emitting device according to the embodiment, the coating step S20 further includes a step S23 for coating the third member 303. The curing step S30 further includes a third curing step S33. Other points are the same as the manufacturing method according to the embodiment. The first member 301, the second member 302, and the third member 303 together constitute the frame member 300. Figure 7 is a flowchart illustrating a second modified example of the method for manufacturing the light-emitting device. Figure 8A is a cross-sectional view illustrating a schematic of the state in which the first member 301 is applied. Figure 8B is a cross-sectional view illustrating a schematic of the state in which the third member 303 is applied. Figure 8C is a cross-sectional view illustrating a schematic of the state in which the second member 302 is applied.

[0061] In the second modified example, the coating step S20 is performed in the following order: coating step S21 for the first member 301, coating step S23 for the third member 303, and coating step S22 for the second member 302. The coating of the first member 301 and the second member 302 is performed in the same manner as in the manufacturing method according to the embodiment. However, the first member 301 does not have to have a flared shape and may have a recess 340 between it and the upper surface of the substrate 10. The cross-sectional shape of the first member 301 may be, for example, circular or elliptical. The third member 303 is applied to the inner side surface of the first member 301 to form an inclined surface 350A. The inclined surface 350A is preferably formed to form an angle of 10 degrees or more and 45 degrees or less with respect to the upper surface of the substrate 10 and to slope downward toward the light-emitting element 20, with 15 degrees or more and 40 degrees or less being particularly preferred.

[0062] The third component 303 is coated by spraying the material for the third component 303 from the jet dispenser 90 toward the inner side of the first component 301 that is closer to the substrate 10. Here, the jet dispenser 90 is moved in a counterclockwise direction along the first component 301. Figure 8B illustrates the state after the jet dispenser 90 has passed. After applying the third member 303, the second member 302 is applied. After applying the second member 302, the cross-sectional shape of the combined portion of the first member 301 and the third member 303 is trapezoidal.

[0063] The materials of the first member 301 and the second member 302 are the same as those used in the manufacturing method according to the embodiment. The first member 301 and the second member 302 have different light reflectances at the emission peak wavelength of the light-emitting element 20. The viscosities of the first member 301 and the second member 302 may be the same or different. The material of the third member 303 can be a resin or ceramic, similar to the first member 301 and the second member 302. Preferably, the third member 303 has a lower viscosity than the first member 301. The lower viscosity of the third member 303 makes it easier to apply to form the inclined surface 350A. The third member 303 has light reflectivity, and its light reflectance at the emission peak wavelength of the light-emitting element 20 is different from that of the second member 302.

[0064] In the second modified example, the curing process S30 consists of a first curing process S31, a second curing process S32, and a third curing process S33. The first curing process S31 is performed before the process S23 in which the third member 303 is applied. The second curing process S32 is performed before the process S22 in which the second member 302 is applied. The third curing process S33 is performed after the process S22 in which the second member 302 is applied. The first curing step S31 can be omitted. That is, the third member 303 may be applied after curing the first member 301 by the first curing step S31, or the first curing step S31 may be omitted and the third member 303 may be applied to the inner side surface of the first member 301 before curing.

[0065] Furthermore, the first curing step S31 and the second curing step S32 may be omitted. That is, the second member 302 may be applied after the first member 301 and the third member 303 have been cured, or it may be applied on the first member 301 before it has been cured. If the first curing step S31 and the second curing step S32 are omitted, the first member 301, the second member 302, and the third member 303 can be cured by the third curing step S33. However, if, for example, the first member 301 is made of ceramics, it is preferable to perform the first curing step S31 or the second curing step S32.

[0066] A second modification of the method for manufacturing the light-emitting device allows for the modification of the shape of the first member 301 so that it has an inclined surface 350A on its inner circumference even if the first member 301 is not flared at the base. For example, even if the inner circumference of the first member 301 has a recess 340 between it and the upper surface of the substrate 10, the third member 303 can be applied to form the inclined surface 350A. Therefore, even materials with high viscosity can be used for the first member 301. Furthermore, the second modification allows for the manufacture of a light-emitting device with improved light extraction efficiency by combining the second member 302 and the third member 303, which have different light reflectances, thereby broadening the range of material selection for the frame member 300 and achieving a balance between shape and light reflectance.

[0067] Next, a light-emitting device 1B having multiple light-emitting elements 20 will be described. As shown in Figure 9, the light-emitting device 1B is equipped with, for example, 10 light-emitting elements 20. The 10 light-emitting elements 20 are connected in series by bonding wires 14. It is preferable that the light-emitting elements 20 are arranged so that they are roughly the same distance from each other. Aside from the number of light-emitting elements 20, the configuration and manufacturing method of the light-emitting device 1B are the same as those described above for the configuration and manufacturing method of the light-emitting device 1. The 10 light-emitting elements 20 may, for example, be connected in parallel in groups of five connected in series. The connection configuration can be changed to suit the characteristics of the light-emitting elements 20.

[0068] In the light-emitting device 1B, the light-emitting element 20 may include a first light-emitting element whose emission peak wavelength is a first wavelength and a second light-emitting element whose emission peak wavelength is a second wavelength different from the first wavelength. In this case, it is preferable that one of the first frame 31 and the second frame 32 has a light reflectance at the first wavelength greater than the light reflectance at the second wavelength, and the other of the first frame 31 and the second frame 32 has a light reflectance at the second wavelength greater than the light reflectance at the first wavelength. As a result, the light-emitting device 1B can align the wavelength bands with high light reflectivity of the first frame 31 and the second frame 32 to the different emission peak wavelengths of the light-emitting element 20, thereby improving the light reflectivity separately for the light from the first light-emitting element and the second light-emitting element.

[0069] In the second modified method for manufacturing the light-emitting device, the light reflectances of the light-emitting elements 20 of the first member 301 and the second member 302 at the emission peak wavelength may be the same or different. Also, the order of the coating step S20 may be such that the first member 301 and the second member 302 are coated first, and then the third member 303 is coated. [Explanation of Symbols]

[0070] 1. Light-emitting device 1A Light-emitting device (one light-emitting element) 1B Light-emitting device (multiple light-emitting elements) 10 circuit boards 11 Base material 12 Wiring 13 Electrode terminal 14 Bonding wires 15 Protective elements 20 Light-emitting elements 30 Frame 31. Slot 1 32. Second slot 35 Slope 40 Sealing member 80 nozzles 81 Nozzle No. 1 81A Discharge port (first nozzle) 81B Side view (No. 1 nozzle) 82 Nozzle No. 2 90 Jet Dispenser 300 Frame members 301 First Member 301A Material (First component) 302 Second Member 302A Material (Second component) 303 Third Member 340 recess 350A Slanted surface (coating process)

Claims

1. A step of coating a substrate on which one or more light-emitting elements are arranged, with a first member applied so as to surround the light-emitting elements at a distance from each other, A step of coating the first coated member with a second member so as to surround the light-emitting element at a distance, The process includes, before or after the step of applying the second member, applying the third member so as to form an inclined surface that is continuous with the inner circumference side surface of the first member and slopes downward toward the light-emitting element at an angle of 10 degrees or more and 45 degrees or less with respect to the upper surface of the substrate, The first member and the second member have light reflectivity, and their light reflectivity at the emission peak wavelength of the light-emitting element is different. A method for manufacturing a light-emitting device in which the third member has light reflectivity and the light reflectivity at the emission peak wavelength of the light-emitting element is different from that of the second member.

2. The method for manufacturing a light-emitting device according to claim 1, wherein the viscosity of the second member is higher than the viscosity of the first member.

3. The method for manufacturing a light-emitting device according to claim 1 or claim 2, wherein the step of applying the first member is to apply the first member by discharging it from a nozzle, and the first member is applied so as to be at a height greater than or equal to the position of the nozzle's discharge opening in a direction perpendicular to the substrate.

4. The base material of the first member and the second member shall be the same, The method for manufacturing a light-emitting device according to claim 3, wherein the step of applying the second member is to move the nozzle away from the first member and dispense the second member from the nozzle to apply it.

5. A method for manufacturing a light-emitting device according to any one of claims 1 to 3, wherein the first member and the second member are made of the same resin.

6. A method for manufacturing a light-emitting device according to any one of claims 1 to 3, wherein the first member is made of ceramics and the second member is made of resin.

7. A method for manufacturing a light-emitting device according to any one of claims 1 to 3, wherein the first member is made of resin and the second member is made of ceramics.

8. The method for manufacturing a light-emitting device according to any one of claims 1 to 7, wherein the step of applying the second member is to apply the second member in multiple layers.

9. The method for manufacturing a light-emitting device according to any one of claims 1 to 8, wherein the step of applying the second member is to position the center of the second member in the width direction further away from the light-emitting element than the center of the first member in the width direction.

10. One or more light-emitting elements, A substrate on which the light-emitting element is arranged, A first frame having a first member surrounds the light-emitting element on the substrate, spaced apart from it, The first member surrounds the light-emitting element at a distance, and the second frame is arranged on the second member, The first frame has a third member that is continuous with the inner side surface of the first member and forms an inclined surface that slopes downward toward the light-emitting element at an angle of 10 degrees or more and 45 degrees or less with respect to the upper surface of the substrate. The first frame and the second frame have light reflectivity, and their light reflectivity at the emission peak wavelength of the light-emitting element is different. The third member is light-reflective, and the light reflectance at the emission peak wavelength of the light-emitting element is different from that of the second member in this light-emitting device.

11. The light-emitting device according to claim 10, wherein the cross-sectional shape of the first member is circular or elliptical.

12. The light-emitting device according to claim 10 or claim 11, wherein the first frame and the second frame are made of the same resin base material.

13. The light-emitting device according to claim 10 or claim 11, wherein the first frame is made of ceramic material and the second frame is made of resin material.

14. The light-emitting device according to claim 10 or claim 11, wherein the first frame is made of resin and the second frame is made of ceramics.

15. The light-emitting device according to any one of claims 10 to 14, wherein the light reflectance of the third member at the emission peak wavelength of the light-emitting element is greater than the light reflectance of the second frame.

16. The light-emitting element includes a first light-emitting element whose emission peak wavelength is a first wavelength and a second light-emitting element whose emission peak wavelength is a second wavelength different from the first wavelength. One of the first frame and the second frame has a light reflectance at the first wavelength greater than the light reflectance at the second wavelength. The light-emitting device according to any one of claims 10 to 15, wherein the other of the first frame and the second frame has a light reflectance at the second wavelength greater than the light reflectance at the first wavelength.

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