Manufacturing method of light-emitting device

Abstract

To manufacture high performance a light emitting device.SOLUTION: A manufacturing method for a light emitting device according to an embodiment of the present invention includes the steps of preparing a plurality of light-emitting elements having an upper surface and a lower surface opposite the upper surface, arranging the plurality of light-emitting elements on a support, arranging an inorganic member having a gap on the upper surfaces of the light-emitting elements and between adjacent light-emitting elements, forming grooves between adjacent light-emitting elements in the inorganic member, and arranging a covering member on the upper surface of the inorganic member above the light-emitting elements and on the grooves, and impregnating the gaps with a portion of the covering member.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] A light-emitting device including a light-emitting element and a covering member composed of an inorganic member that covers a part of the light-emitting element is known (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A light-emitting device including a covering member composed of such an inorganic member still has room for improvement in order to improve the performance of the light-emitting device. The performance of the light-emitting device in this specification is, for example, insulation, strength, or heat resistance.

[0005] Therefore, an object of one embodiment of the present disclosure is to provide a method for manufacturing a high-performance light-emitting device.

Means for Solving the Problems

[0006] A method for manufacturing a light-emitting device according to an embodiment of the present disclosure includes a step of preparing a plurality of light-emitting elements having an upper surface and a lower surface located on the opposite side of the upper surface, a step of arranging the plurality of light-emitting elements on a support, a step of arranging an inorganic member having voids between the upper surface of the light-emitting element and adjacent light-emitting elements, a step of forming a groove between adjacent light-emitting elements in the inorganic member, and a step of arranging a covering member on the upper surface of the inorganic member located above the light-emitting element and in the groove, and impregnating a part of the covering member into the voids.

Effects of the Invention

[0007] According to an embodiment of the present disclosure, a high-performance light-emitting device can be manufactured.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4A

Figure 4B

Figure 4C

Figure 4D

Figure 4E

Figure 4F

Figure 4G

Figure 5

Figure 6A

Figure 6B

Figure 6C

Figure 6D

Figure 6E

Figure 6F

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In the following description, terms indicating specific directions and positions (for example, "up", "down", and other terms including those terms) are used as necessary. However, the use of those terms is for facilitating the understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meanings of those terms. Also, parts denoted by the same reference numerals in a plurality of drawings indicate the same or equivalent parts or members.

[0010] Furthermore, the embodiments shown below exemplify light-emitting devices and the like for embodying the technical idea of the present invention, and do not limit the present invention to the following. Also, dimensions, materials, shapes, relative arrangements, etc. of the components described below are not intended to limit the scope of the present invention only to those, but are intended to be illustrative unless otherwise specified. Also, the content described in one embodiment is applicable to other embodiments and modifications. Also, the sizes and positional relationships of the members shown in the drawings may be exaggerated for clarity of explanation. Furthermore, in order to avoid the drawings becoming overly complex, a schematic diagram in which the illustration of some elements is omitted or an end view showing only the cut surface as a cross-sectional view may be used.

[0011] <Method for Manufacturing a Light-Emitting Device> FIG. 1 is a schematic cross-sectional view of a light-emitting device 1 according to an embodiment, FIG. 2 is a schematic diagram enlarging a part of the II-II cross-section of FIG. 1, FIGS. 4A, 4B, and 4D to 4G are schematic cross-sectional views for explaining a manufacturing method of the light-emitting device 1 according to an embodiment, and FIG. 4C is a schematic diagram enlarging a part of the IV-IV cross-section of FIG. 4B. As shown in FIGS. 1 and 2, the light-emitting device 1 of the present embodiment includes a light-emitting element 2, an inorganic member 3 that covers the upper surface 23 and the side surface 25 of the light-emitting element 2 and has pores 33, and a covering member 6 that covers the side surface of the inorganic member 3. The covering member 6 is disposed in the pores 33. With reference to FIGS. 4A to 4G, an example of a manufacturing method of the light-emitting device 1 of the present embodiment will be described. In the present specification, a case where the pore 33 is a cavity may be referred to as a "void 33a".

[0012] As shown in FIG. 4A, the manufacturing method of the light-emitting device 1 of the present embodiment includes a step of preparing a plurality of light-emitting elements 2 having an upper surface 23 and a lower surface 24 located on the opposite side of the upper surface 23, and a step of disposing the plurality of light-emitting elements 2 on a support 5. Further, as shown in FIGS. 4B and 4C, the manufacturing method of the light-emitting device 1 includes a step of disposing an inorganic member 3a having voids 33a on the upper surface 23 of the light-emitting element 2 and between adjacent light-emitting elements 2, a step of forming grooves 35a between adjacent light-emitting elements 2 in the inorganic member 3a as shown in FIG. 4D, and a step of disposing a covering member 6 on the upper surface 36a and the grooves 35a located above the light-emitting element 2 in the inorganic member 3a and impregnating a part of the covering member 6 into the voids 33a as shown in FIG. 4E.

[0013] With the above-described manufacturing method of the light-emitting device 1, a high-performance light-emitting device 1 can be manufactured. Details will be described below.

[0014] (Step of preparing the light-emitting element 2) As shown in FIG. 4A, the manufacturing method of the light-emitting device 1 of the present embodiment includes a step of preparing a plurality of light-emitting elements 2 having an upper surface 23 and a lower surface 24 located on the opposite side of the upper surface 23.

[0015] As the light-emitting element 2, a semiconductor light-emitting element such as a light-emitting diode (LED) chip or a semiconductor laser (LD) chip can be preferably used. In the example shown in FIG. 4A, the light-emitting element 2 has a semiconductor structure 21 and electrodes 22. In the example shown in FIG. 4A, a pair of electrodes 22 are arranged on the upper surface 23 side of the light-emitting element 2. Further, the light-emitting element 2 has a side surface 25 connecting the upper surface 23 and the lower surface 24. In the example shown in FIG. 4A, each of the upper surface 23, the lower surface 24, and the side surface 25 of the light-emitting element 2 is the upper surface, the lower surface, and the side surface of the semiconductor structure 21.

[0016] The semiconductor structure 21 includes an n-side semiconductor layer, a p-side semiconductor layer, and a light-emitting layer sandwiched between the n-side semiconductor layer and the p-side semiconductor layer. The light-emitting layer may have a single quantum well (SQW) structure or a multiple quantum well (MQW) structure including a plurality of well layers. The semiconductor structure 21 includes a plurality of semiconductor layers made of a nitride semiconductor. The nitride semiconductor includes all compositions in which the composition ratios x and y are changed within their respective ranges in the chemical formula consisting of In x Al y Ga 1-x-y N (0 ≦ x, 0 ≦ y, x + y ≦ 1). The emission peak wavelength of the light-emitting layer can be appropriately selected according to the purpose. The light-emitting layer is configured to emit, for example, visible light or ultraviolet light.

[0017] The light-emitting element 2 may or may not have a translucent support substrate on the lower surface of the semiconductor structure 21. When the light-emitting element 2 has a support substrate, the surface of the support substrate located on the side opposite to the surface facing the semiconductor structure 21 becomes the lower surface 24 of the light-emitting element 2.

[0018] The light-emitting element 2 may have one semiconductor structure 21 provided on the main surface of one support substrate, or may have a plurality of semiconductor structures 21 provided on the main surface of one support substrate. Further, one semiconductor structure 21 may have only one light-emitting layer, or may have a plurality of light-emitting layers. The structure of the semiconductor structure 21 having a plurality of light-emitting layers may be a structure including a plurality of light-emitting layers between one n-type semiconductor layer and one p-type semiconductor layer, or may be a structure in which the structure including the n-type semiconductor layer, the light-emitting layer, and the p-type semiconductor layer in this order is repeated a plurality of times.

[0019] Examples of the material of the support substrate include sapphire, spinel (MgAl 2 O 4 ), and nitride semiconductors such as gallium nitride.

[0020] The light-emitting element 2 can have an arbitrary shape in plan view. The shape of the light-emitting element 2 in plan view is, for example, rectangular (that is, square, rectangular, etc.), triangular, or hexagonal. In plan view, when the shape of the light-emitting element 2 is rectangular, the size of the light-emitting element 2 can be, for example, 1 mm × 1 mm. Note that the plan view in this specification means viewing from the upper surface 23 side of the light-emitting element 2.

[0021] (Step of arranging a plurality of light-emitting elements 2) As shown in FIG. 4A, the manufacturing method of the light-emitting device 1 according to this embodiment includes a step of arranging a plurality of light-emitting elements 2 on a support 5. As the support 5, an adhesive sheet such as polyimide can be used. In the example shown in FIG. 4A, the light-emitting elements 2 are arranged on the support 5 such that the lower surface 24 of the light-emitting element 2 (that is, the surface of the light-emitting element 2 on the side where the electrode 22 is not arranged) faces the support 5. Thereby, in the step of arranging the inorganic member 3a described later, the inorganic member 3a is easily coated on the side surface 26 of the electrode 22. Also, in the example shown in FIG. 4A, a light-transmissive member 4 is arranged between the support 5 and the light-emitting element 2, and the light-transmissive member 4 is arranged on the lower surface 24 of each of the plurality of light-emitting elements 2. Such a configuration can be obtained, for example, by arranging the light-transmissive member 4 on the support 5 and arranging the light-emitting element 2 on the upper surface 43 of the light-transmissive member 4 in the step of arranging the plurality of light-emitting elements 2. Alternatively, it can be obtained by arranging the light-emitting element 2 on the light-transmissive member 4 and arranging the laminate of the light-transmissive member 4 and the light-emitting element 2 on the support 5.

[0022] The light-transmissive member 4 can contain a wavelength-converting material capable of wavelength-converting at least a part of the light from the light-emitting element 2. Thereby, the chromaticity adjustment of the light-emitting device 1 manufactured by the manufacturing method of this embodiment becomes easy. The wavelength-converting material contained in the light-transmissive member 4 may be one type or a plurality of types.

[0023] The light-transmissive member 4 may be composed of a wavelength-converting material and a base material, or may be composed of only the wavelength-converting material. Also, the light-transmissive member 4 may have a configuration including an inorganic material and / or a light diffusing material described later with the wavelength-converting member as the base material.

[0024] When the light-transmissive member 4 is composed of a wavelength-converting material and a base material, the wavelength-converting material may be contained in the base material or may be arranged on the surface of the base material. When the wavelength-converting material is arranged on the surface of the base material, the wavelength-converting material can be arranged on the surface of the base material facing the light-emitting element 2. Also, only the wavelength-converting material may be arranged on the surface of the base material, or a resin containing the wavelength-converting material may be arranged.

[0025] When the wavelength conversion material is contained in the base material, the wavelength conversion material may be dispersed and arranged in the base material, or may be unevenly distributed.

[0026] Examples of the material of the base material include inorganic materials such as glass, ceramics, and sapphire, and organic materials such as resins or hybrid resins containing one or more of silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, acrylic resin, phenol resin, and fluororesin.

[0027] Known phosphors can be used as the wavelength conversion material. Examples of the phosphor include yttrium aluminum garnet-based phosphors (e.g., (Y,Gd) 3 (Al,Ga) 5 O 12 :Ce), lutetium aluminum garnet-based phosphors (e.g., Lu 3 (Al,Ga) 5 O 12 :Ce), terbium aluminum garnet-based phosphors (e.g., Tb 3 (Al,Ga) 5 O 12 :Ce), CCA-based phosphors (e.g., Ca 10 (PO 4 ) 6 Cl 2 :Eu), SAE-based phosphors (e.g., Sr 4 Al 14 O 25 :Eu), chlorosilicate-based phosphors (e.g., Ca 8 MgSi 4 O 16 Cl 2 :Eu), silicate-based phosphors (e.g., (Ba,Sr,Ca,Mg) 2 SiO 4 :Eu), β-sialon-based phosphors (e.g., (Si,Al) 3 (O,N) 4 :Eu) or α-sialon-based phosphors (e.g., Ca(Si,Al) 12 (O,N) 16 :Eu) and other oxynitride-based phosphors, LSN-based phosphors (e.g., (La,Y) 3 Si6 N 11 :Ce), BSESN-based phosphors (e.g., (Ba,Sr) 2 Si 5 N 8 :Eu), SLA-based phosphors (e.g., SrLiAl 3 N 4 :Eu), CASN-based phosphors (e.g., CaAlSiN 3 :Eu) or SCASN-based phosphors (e.g., (Sr,Ca)AlSiN 3 :Eu), etc., nitride-based phosphors, KSF-based phosphors (e.g., K 2 SiF 6 :Mn), KSAF-based phosphors (e.g., K 2 (Si 1-x Al x )F 6-x :Mn where x satisfies 0 < x < 1.) or MGF-based phosphors (e.g., 3.5MgO·0.5MgF 2 ·GeO 2 :Mn), etc., fluoride-based phosphors, quantum dots having a perovskite structure (e.g., (Cs,FA,MA)(Pb,Sn)(F,Cl,Br,I) 3 where FA and MA represent formamidinium and methylammonium, respectively.), II-VI group quantum dots (e.g., CdSe), III-V group quantum dots (e.g., InP), or quantum dots having a chalcopyrite structure (e.g., (Ag,Cu)(In,Ga)(S,Se) 2 ) can be used.

[0028] The light-transmitting member 4 can contain a light diffusing material according to the purpose. As the light diffusing material, those known in the art can be used. As the light diffusing material, for example, titanium oxide, silicon oxide, aluminum oxide, barium titanate, yttrium aluminum perovskite (YAP) can be used.

[0029] (Step of arranging the inorganic member 3a) As shown in FIGS. 4B and 4C, the manufacturing method of the light-emitting device 1 according to this embodiment includes a step of disposing an inorganic member 3a having a gap 33a on the upper surface 23 of the light-emitting element 2 and between adjacent light-emitting elements 2. In the step of disposing a plurality of light-emitting elements 2, a light-transmissive member 4 is disposed between the support 5 and the light-emitting element 2. When the light-transmissive member 4 is disposed on the lower surface 24 of each of the plurality of light-emitting elements 2, in the step of disposing the inorganic member 3a, the inorganic member 3a is further disposed on the side surface 41 of the light-transmissive member 4.

[0030] The inorganic member 3a is, for example, a light-reflective member including a light-reflective material 32, silicon dioxide, and an alkali metal.

[0031] When the inorganic member 3a is composed of a light-reflective member including a light-reflective material 32, silicon dioxide, and an alkali metal, the step of disposing the inorganic member 3a includes a step of mixing the powder of the light-reflective material 32, the powder of silicon dioxide, and an alkali metal aqueous solution to prepare a mixture, a step of applying the mixture, and a step of heating the mixture.

[0032] In the step of preparing the mixture, the concentration of the alkali metal aqueous solution is preferably 1 mol / L or more, for example, from the viewpoints of ease of curing and strength after curing. On the other hand, it is preferably 5 mol / L or less from the viewpoint of reducing the precipitation of excess alkali metal after mixing. The alkali metal aqueous solution is, for example, a potassium hydroxide solution or a sodium hydroxide solution. In the step of preparing the mixture, for example, after mixing the mixed powder, it is defoamed and stirred by a stirring defoamer that can be stirred under reduced pressure.

[0033] In the step of applying the mixture, the mixture is applied from above the light-emitting element 2 to cover the upper surface of the support 5, the side surface 25 of the light-emitting element 2, and the upper surface 23 of the light-emitting element 2. When the light-transmissive member 4 is disposed between the light-emitting element 2 and the support 5, the mixture covers the side surface 41 of the light-transmissive member 4 and the region on the upper surface 43 of the light-transmissive member 4 where the light-emitting element 2 is not disposed.

[0034] In the step of heating the mixture, the mixture is cured by heating to form the inorganic member 3a. The inorganic member 3a contains alkali metal silicate produced by the reaction of silicon dioxide contained in the mixture and an aqueous alkali metal solution. Examples of the alkali metal silicate include potassium silicate, sodium silicate, and lithium metasilicate. The step of heating the mixture includes, for example, a pre-curing step of heating and curing the mixture at a first temperature T1 and a main-curing step of heating and curing the mixture at a second temperature T2 higher than the first temperature T1. The pre-curing step is, for example, heated at a first temperature T1 of 80°C or higher and 100°C or lower for 10 minutes or more and 2 hours or less. The main-curing step is, for example, heated at a second temperature T2 of 150°C or higher and 250°C or lower for 10 minutes or more and 3 hours or less.

[0035] The light reflecting material 32 can reflect the light emitted from the light emitting element 2. The light reflecting material 32 includes, for example, at least one selected from boron nitride, aluminum nitride, and aluminum oxide. Since boron nitride, aluminum nitride, or aluminum oxide is a material with excellent thermal conductivity, an inorganic member 3a with excellent heat dissipation can be obtained. Further, the coating member 6 includes a plurality of light reflecting materials 32, and at least some of the plurality of light reflecting materials 32 are in contact with each other. Thereby, it is possible to reduce the shrinkage of the inorganic member 3a formed by the heat curing of the mixture. The inorganic member 3a may further contain other particles such as zirconium oxide and titanium oxide.

[0036] The light reflecting material 32 is, for example, plate-shaped (including flaky) particles having two main surfaces. The light reflecting material 32 may be primary particles, secondary particles in which two or more primary particles are aggregated, or a mixture of primary particles and secondary particles.

[0037] The average aspect ratio of the primary particles of the light reflecting material 32 is preferably 10 or more, more preferably 10 or more and 70 or less. When the light reflecting material 32 is boron nitride, the average aspect ratio of the light reflecting material 32 is, for example, 16.5 or more and 19.2 or less. When the light reflecting material 32 is aluminum oxide, the average aspect ratio of the light reflecting material 32 is, for example, 10 or more and 70 or less. The average aspect ratio of the light reflecting material 32 can be calculated, for example, by the following method.

[0038] (Method for calculating average aspect ratio) The average aspect ratio of the light reflecting material 32 is calculated by measuring the length of the major axis and the length of the minor axis of the light reflecting material 32 contained in the inorganic member 3a in the cross section of the inorganic member 3a after arranging the inorganic member 3a. First, a cross section passing through the center of the upper surface 23 of the light emitting element 2 and substantially orthogonal to the upper surface 23 is exposed. Next, the exposed cross section is mirror-polished. Then, the mirror-polished cross section is observed with a scanning electron microscope (SEM) at a magnification of 2000 to 3000 times, the cross section of the light reflecting material 32 is extracted from the obtained image, and a measurement region containing cross sections of about 1000 light reflecting materials 32 is selected. The average aspect ratio of the light reflecting material 32 can also be calculated by measuring the length of the major axis and the length of the minor axis of the light reflecting material 32 contained in the inorganic member 3 in the cross section of the light emitting device 1 after manufacturing the light emitting device 1.

[0039] Next, using image analysis software, the length of the major axis and the length of the minor axis of each cross section of the extracted light reflecting material 32 are measured one by one, and the ratio of the length of the major axis to the length of the minor axis (aspect ratio) is calculated. Then, the average value of the aspect ratios of 100 light reflecting materials 32 is taken as the average aspect ratio.

[0040] The average particle size of the light reflecting material 32 is preferably 0.6 μm or more and 43 μm or less. When the light reflecting material 32 is boron nitride, the average particle size of the light reflecting material 32 is, for example, 6 μm or more and 43 μm or less. When the light reflecting material 32 is aluminum oxide, the average particle size of the light reflecting material 32 is, for example, 0.6 μm or more and 10 μm or less.

[0041] Here, since the deformation and alteration of the light reflecting material 32 due to the manufacturing process are slight, the shape and dimensions of the powder of the light reflecting material 32 are substantially the same as the shape and dimensions of the light reflecting material 32 contained in the inorganic members 3a and 3. Therefore, the average particle diameter of the light reflecting material 32 can be calculated, for example, by the following method.

[0042] (Method for calculating average particle diameter) The particle diameter of the powder of the light reflecting material 32 is calculated, for example, using a scanning electron microscope "TM3030Plus" manufactured by Hitachi High-Technologies Corporation. First, one side of a carbon double-sided tape is attached to the sample stage of the microscope, and then the powder of the light reflecting material 32 is placed on the other side of the double-sided tape. The magnification of the microscope is set to 1000 to 2000 times, and images of 100 powders (particles) of the light reflecting material 32 are acquired. Then, the particle diameter of each particle is measured using image analysis software.

[0043] In this specification, the particle diameter of the powder of the light reflecting material 32 means the maximum diameter among the diameters when viewed from one main surface of the light reflecting material 32. Next, the median diameter of the measured particles is calculated, and this calculated value is taken as the average particle diameter of the light reflecting material 32. Note that the particle diameter of the powder of the light reflecting material 32 may be measured and calculated by extracting a cross-section of the inorganic member 3a by SEM and using image analysis software. Also, the average particle diameter of the light reflecting material 32 can be calculated by extracting a cross-section of the inorganic member 3 by SEM and measuring it using image analysis software after manufacturing the light emitting device 1.

[0044] The weight ratio of the silicon dioxide powder to the light reflecting material 32 powder is, for example, 1:4 or more and 1:1 or less. That is, the weight of the light reflecting material 32 powder is 1 time or more and 4 times or less the weight of the silicon dioxide powder, relative to the weight of the silicon dioxide powder. The weight ratio of the alkali metal aqueous solution to the mixed powder is, for example, 2:10 or more and 8:10 or less. That is, the weight of the mixed powder is 1.25 times or more and 5 times or less the weight of the alkali metal aqueous solution, relative to the weight of the alkali metal aqueous solution. If the weight of the alkali metal aqueous solution is too small relative to the weight of the mixed powder, a plurality of fine lumps are formed when the mixed powder and the alkali metal aqueous solution are mixed, making molding difficult. On the other hand, if the weight of the alkali metal aqueous solution is too large relative to the weight of the mixed powder, cracks may occur when the mixture is heated and cured, or the strength of the inorganic member 3a obtained by curing may decrease.

[0045] The inorganic member 3a having voids 33a includes, for example, as shown in FIG. 4C, a light reflecting material 32 and a support member 31a that supports the light reflecting material 32. The voids 33a are formed, for example, in the support member 31a during the curing process. The support member 31a contains silicon dioxide and an alkali metal. By configuring the support member 31a with an inorganic material, the support member 31a has heat resistance against heat from the light emitting element 2 and the translucent member 4.

[0046] (Step of forming groove 35a) As shown in FIG. 4D, the manufacturing method of the light emitting device 1 of the present embodiment includes a step of forming a groove 35a between adjacent light emitting elements 2 in the inorganic member 3a. Thereby, in the impregnation step described later, the coating member 6 can be impregnated into the voids 33a of the inorganic member 3a from both the upper surface 36a of the inorganic member 3a and the groove 35a, and the coating member 6 can be efficiently impregnated throughout the inorganic member 3a. Note that the groove 35a opens to the upper surface 23 side of the light emitting element 2.

[0047] In the example shown in FIG. 4D, the shape of the groove 35a in cross-sectional view is a rectangular shape defined by a bottom surface and side surfaces that are perpendicular to each other. The shape of the groove 35a in cross-sectional view is not limited to the shape described above, and the side surface of the groove 35a may be inclined with respect to the bottom surface of the groove 35a. Further, the bottom surface of the groove 35a may be a flat surface or a curved surface that is recessed toward the support 5 side. Further, the shape of the groove 35a in cross-sectional view may be a shape in which the lower ends of the inclined side surfaces are in contact with each other without having a bottom surface (that is, a V-shaped).

[0048] FIG. 5 is a schematic cross-sectional view for explaining another example of the process of forming the groove 35a. In the example shown in FIG. 4D, the groove 35a does not penetrate the inorganic member 3a. However, the groove 35a is not limited to this, and in the process of forming the groove 35a, the groove 35a may penetrate the inorganic member 3a as shown in FIG. 5. In the process of forming the groove 35a, when the groove 35a penetrates the inorganic member 3a, in the impregnation process described later, the area of the coating member 6 in contact with the inorganic member 3a increases, and the coating member 6 can be efficiently impregnated throughout the inorganic member 3a.

[0049] (Impregnation step) As shown in FIG. 4E, the manufacturing method of the light-emitting device 1 of the present embodiment includes a step of disposing the coating member 6 on the upper surface 36a and the groove 35a located above the light-emitting element 2 in the inorganic member 3a and impregnating a part of the coating member 6 into the void 33a.

[0050] By impregnating a part of the coating member 6 into the void 33a, the light-emitting device 1 including the highly insulating inorganic member 3a can be manufactured. The reason is considered as follows. When the coating member 6 is impregnated into the void 33a, it is possible to reduce the intrusion of moisture present in the atmosphere into the pores 33, and thus it is possible to reduce the reaction between the alkali metal silicate contained in the inorganic member 3a and the moisture. Thereby, the generation of metal ions derived from the alkali metal silicate can be reduced, and the generation of leakage current can be reduced.

[0051] Further, the coating member 6 is disposed on both the upper surface 36a and the groove 35a located above the light-emitting element 2 in the inorganic member 3a, so that the inorganic member 3a can be impregnated into the void 33a of the inorganic member 3a from both the upper surface 36a and the groove 35a of the inorganic member 3a, and can be efficiently impregnated throughout the inorganic member 3a. By impregnating a part of the coating member 6 into the void 33a, the light-emitting device 1 including the inorganic member 3a having high mechanical strength can be manufactured.

[0052] The void 33a of the inorganic member 3a is open on the surface of the inorganic member 3a. When the coating member 6 is disposed on the upper surface 36a and the groove 35a of the inorganic member, the coating member 6 is impregnated into the inorganic member 3a from the opening of the void 33a located on the surfaces of the upper surface 36a and the groove 35a of the inorganic member 3a. In the impregnating step, it is preferable that the coating member 6 is impregnated throughout the entire void 33a of the inorganic member 3a. Thereby, the mechanical strength of the entire inorganic member 3a can be enhanced.

[0053] As a method of disposing the coating member 6, the coating member 6 may be applied to the upper surface 36a and the groove 35a of the inorganic member 3a from the upper surface 23 side with respect to the light-emitting element 2, or the inorganic member 3a may be immersed in the coating member 6.

[0054] In the step of impregnating the coating member 6, the coating member 6 can be disposed so that the groove 35a is completely filled. Thereby, the thickness of the coating member 6 in the direction orthogonal to the surface of the groove 35a becomes large, and in the manufacturing method of the light-emitting device 1, the light-emitting device 1 including the inorganic member 3a having high mechanical strength can be manufactured. In the step of disposing the coating member 6, the coating member 6 may be disposed so that the groove 35a is not completely filled. For example, the coating member 6 may be disposed in a thin film shape on the surface of the groove 35a.

[0055] In the step of disposing the coating member 6, examples of the coating member 6 include a mixture containing polysilazane and a solvent, a mixture containing inorganic particles such as silicon dioxide and aluminum oxide, and a solvent. The inorganic particles are sized to be able to pass through the pores 33. The solvent can be used to facilitate the impregnation of the coating member 6. Examples of the solvent include alcohol and dibutyl ether. After impregnating the voids 33a of the inorganic member 3a with the coating member 6, the coating member 6 can be heated. By heating the coating member 6, the solvent contained in the coating member 6 can be volatilized. When the coating member 6 contains polysilazane, heating the coating member 6 forms a glass containing silicon dioxide.

[0056] (Step of exposing the electrode 22) As shown in FIG. 4F, the method for manufacturing the light-emitting device 1 according to the present embodiment can include a step of exposing the electrode 22 by removing the inorganic member 3a and the coating member 6 located above the upper surface 23 of the light-emitting element 2 after the impregnation step. Specifically, in the step of exposing the electrode 22, the inorganic member 3a and the coating member 6 located above the upper surface 23 of the light-emitting element 2 can be removed by grinding. Thereby, the upper surface 27 of the electrode 22 is exposed, and the light-emitting device 1 in which the side surface 26 is covered with the inorganic member 3a can be manufactured. In the method for manufacturing the light-emitting device 1, since the voids 33a are impregnated with the coating member 6, in the step of exposing the electrode 22, chipping of the coating member 6 due to grinding can be reduced as compared with the case where the voids 33a are not impregnated with the coating member 6, and the electrode 22 can be exposed with high processing accuracy.

[0057] In the step of exposing the electrode 22, the inorganic member 3a and the coating member 6 located above the upper surface 23 of the light-emitting element 2 may be removed by etching.

[0058] (Step of cutting) As shown in FIG. 4G, the manufacturing method of the light-emitting device 1 according to this embodiment can include a step of cutting the inorganic member 3a and the coating member 6 at the position of the groove 35a after the impregnation step. Thereby, the light-emitting device 1 in which the coating members 6 are arranged on both side surfaces of the inorganic member 3a can be manufactured. In the cutting step, it is preferable to cut using a blade C having a width narrower than that of the groove 35a. Thereby, the thickness of the coating member 6 that covers the side surface of the inorganic member 3a can be increased, and the light-emitting device 1 having the inorganic member 3a with high mechanical strength can be manufactured. Further, when the groove 35a does not penetrate the inorganic member 3a, the coating member 6 is impregnated into the gap 33a of the inorganic member 3a located below the groove 35a. Therefore, compared with the case where the coating member 6 is not impregnated into the gap 33a, chipping of the coating member 6 due to cutting can be reduced, and the inorganic member 3a and the coating member 6 can be cut with high processing accuracy.

[0059] FIGS. 6A to 6F are schematic cross-sectional views for explaining another example of the manufacturing method of the light-emitting device 1 according to an embodiment. The manufacturing method of the light-emitting device 1 according to this embodiment is different from the manufacturing method of the light-emitting device 1 shown in FIGS. 4A to 4G in that a pair of electrodes 22 are arranged on the lower surface 24 side of the light-emitting element 2, and the light-emitting element 2 is arranged on the support 5 so that the lower surface 24 of the light-emitting element 2 (that is, the surface of the light-emitting element 2 on the side where the electrodes 22 are arranged) faces the support 5.

[0060] As shown in Fig. 6A, the manufacturing method of the light-emitting device 1 according to this embodiment includes a step of preparing a plurality of light-emitting elements 2 having an upper surface 23 and a lower surface 24 located on the opposite side of the upper surface 23, and a step of arranging the plurality of light-emitting elements 2 on a support 5. Further, as shown in Fig. 6B, the manufacturing method of the light-emitting device 1 includes a step of arranging an inorganic member 3a having a void 33a between the upper surface 23 of the light-emitting element 2 and adjacent light-emitting elements 2, and as shown in Fig. 6C, a step of forming a groove 35a between adjacent light-emitting elements 2 in the inorganic member 3a. As shown in Fig. 6D, the manufacturing method includes a step of arranging a covering member 6 on the upper surface 36a and the groove 35a located above the light-emitting element 2 in the inorganic member 3a, and impregnating a part of the covering member 6 into the void 33a. Since the steps of arranging the inorganic member 3a, forming the groove 35a, impregnating, and cutting are the same as the manufacturing method of the light-emitting device 1 shown in Figs. 4A to 4G, the description is omitted here.

[0061] (Step of preparing the light-emitting element 2) As shown in Fig. 6A, the manufacturing method of the light-emitting device 1 according to this embodiment includes a step of preparing a plurality of light-emitting elements 2 having an upper surface 23 and a lower surface 24 located on the opposite side of the upper surface 23. In the example shown in Fig. 6A, a pair of electrodes 22 are arranged on the lower surface 24 side of the light-emitting element 2. Since the rest is the same as the manufacturing method of the light-emitting device 1 shown in Fig. 4A, the description is omitted here.

[0062] (Step of arranging a plurality of light-emitting elements 2) As shown in Fig. 6A, the manufacturing method of the light-emitting device 1 according to this embodiment includes a step of arranging a plurality of light-emitting elements 2 on a support 5. As the support 5, a wiring board or an adhesive sheet such as polyimide can be used. In the example shown in Fig. 6A, the light-emitting elements 2 are arranged on the support 5 such that the lower surface 24 of the light-emitting element 2 faces the support 5. Further, in the example shown in Fig. 6A, in the step of arranging a plurality of light-emitting elements 2, a light-transmissive member 4 is arranged on the upper surface 23 of each of the plurality of light-emitting elements 2. However, it is not limited thereto, and the light-transmissive member 4 may not be arranged on all the upper surfaces 23 of the plurality of light-emitting elements 2, or may not be arranged on the upper surfaces 23 of some of the plurality of light-emitting elements 2.

[0063] (Step of exposing the light-emitting surface 11) As shown in Fig. 6E, the method for manufacturing the light-emitting device 1 of the present embodiment can include a step of exposing the light-emitting surface 11 by removing the inorganic member 3a and the coating member 6 located above the upper surface 43 of the light-transmissive member 4 after the step of arranging the coating member 6. The light-emitting surface 11 is the upper surface 43 of the light-transmissive member 4 and is the surface from which light is emitted in the light-emitting device 1. When arranging the light-transmissive member 4 on the upper surface 23 of each of the plurality of light-emitting elements 2 in the step of arranging the plurality of light-emitting elements 2, in the step of exposing the light-emitting surface 11, the step of exposing the light-emitting surface 11 can be included by removing the inorganic member 3a and the coating member 6 located above the upper surface 43 of the light-transmissive member 4. Specifically, in the step of exposing the light-emitting surface 11, the inorganic member 3a and the coating member 6 located above the upper surface 43 of the light-transmissive member 4 can be removed by grinding.

[0064] When the light-transmissive member 4 is not arranged on the upper surface 23 of each of the plurality of light-emitting elements 2 in the step of arranging the plurality of light-emitting elements 2, in the step of exposing the light-emitting surface 11, the step of exposing the light-emitting surface 11 (i.e., the upper surface 23 of the light-emitting element 2) can be included by removing the inorganic member 3a and the coating member 6 located above the upper surface 23 of the light-emitting element 2.

[0065] In the method for manufacturing the light-emitting device 1 shown in Figs. 6A to 6F, the same effects as those of the method for manufacturing the light-emitting device 1 shown in Figs. 4A to 4G are also achieved. Therefore, in the method for manufacturing the light-emitting device 1 shown in Figs. 6A to 6F, a high-performance light-emitting device 1 can also be manufactured.

[0066] <Light-emitting device> As shown in FIGS. 1 and 2, the light-emitting device 1 includes a light-emitting element 2, an inorganic member 3 that covers the upper surface 23 and the side surface 25 of the light-emitting element 2 and has pores 33, and a covering member 6 that covers the inorganic member 3. The covering member 6 is disposed in the pores 33. With this configuration, the light-emitting device 1 has an inorganic member 3a with high mechanical strength as compared with a light-emitting device in which the covering member 6 is not disposed in the pores 33. Further, since the covering member 6 is disposed in the pores 33, the light-emitting device 1 includes an inorganic member 3a with high insulation. Therefore, a high-performance light-emitting device 1 can be provided.

[0067] Since the light-emitting element 2 is the same as the light-emitting element 2 in the manufacturing method of the light-emitting device 1, the description thereof is omitted here.

[0068] The inorganic member 3 is further disposed on the side surface 26 of the electrode 22 provided on the upper surface 23 of the light-emitting element 2. In the example shown in FIG. 2, the inorganic member 3 includes a light reflecting material 32 and a support member 31 that supports the light reflecting material 32. The support member 31 includes silicon dioxide and an alkali metal. Since the light reflecting material 32 is the same as the light reflecting material 32 in the manufacturing method of the light-emitting device 1, the description thereof is omitted here. The inorganic member 3 includes an alkali metal silicate produced by the reaction of silicon dioxide and an alkali metal silicate. Examples of the alkali metal silicate include potassium silicate, sodium silicate, and lithium metasilicate.

[0069] The covering member 6 has a first portion 6a disposed in the pores 33 and a second portion 6b disposed on the side surface 37 of the inorganic member 3. By having the second portion 6b disposed on the side surface 37 of the inorganic member 3, the impact of an external force applied to the light-emitting device 1 can be reduced. In the example shown in FIG. 1, the covering member 6 has a second portion 6b disposed on the side surface 37 and the bottom surface 38 of the inorganic member 3.

[0070] The covering member 6 is composed of, for example, a mixture containing polysilazane and a solvent. When the covering member 6 is composed of a mixture containing polysilazane and a solvent, when the polysilazane contained in the covering member 6 is heated, glass containing silicon dioxide is formed. In the example shown in FIG. 2, glass and a solvent are arranged in the pores 33 as the covering member 6. Note that only glass may be arranged in the pores 33.

[0071] FIG. 3 is an enlarged schematic view of a part of the cross section taken along line II-II of FIG. 1 in another example of the light-emitting device according to an embodiment. The covering member 6 can be composed of a mixture containing inorganic particles such as silicon dioxide and aluminum oxide and a solvent. When the covering member 6 is composed of a mixture containing inorganic particles and a solvent, as shown in FIG. 3, inorganic particles 61 and a solvent 62 are arranged in the pores 33 as the covering member 6. Note that the covering member 6 may be composed of only the inorganic particles 61.

[0072] In the example shown in FIG. 1, the light-emitting device 1 includes a light-transmitting member 4 disposed on the lower surface 24 of the light-emitting element 2. Further, the inorganic member 3 covers the side surface 41 of the light-transmitting member 4. The lower surface 42 of the light-transmitting member 4 exposed from the inorganic member 3 is the light-emitting surface 11 of the light-emitting device 1.

[0073] The light-transmitting member 4 may be disposed on the lower surface 24 of the light-emitting element 2 via an adhesive, or may be directly disposed without an adhesive.

[0074] In the example shown in FIG. 1, the light-emitting device 1 includes the light-transmitting member 4. However, the present invention is not limited to this, and the light-emitting device 1 may not include the light-transmitting member 4. When the light-emitting device 1 does not include the light-transmitting member 4, the lower surface 24 of the light-emitting element 2 becomes the light-emitting surface 11 of the light-emitting device 1.

[0075] Details of the light-transmitting member 4 are as described above, and thus the description thereof is omitted here.

[0076] In the example shown in FIG. 1, the light-emitting device 1 does not include a wiring board. However, the light-emitting device 1 is not limited to this and may include a wiring board. When the light-emitting device 1 includes a wiring board, the electrode 22 of the light-emitting element 2 is electrically connected to the wiring of the wiring board. Further, on the surface of the wiring board facing the light-emitting element 2, the inorganic member 3 can be disposed in a region other than the region electrically connected to the electrode 22 of the light-emitting element 2. Further, one light-emitting element 2 may be electrically connected to one wiring board, or a plurality of light-emitting elements 2 may be electrically connected. As the base material of the wiring board, for example, aluminum nitride can be used.

[0077] (Aspects of the present invention) The present invention includes the following aspects. <Aspect 1> Preparing a plurality of light-emitting elements having an upper surface and a lower surface located on the opposite side of the upper surface; Disposing the plurality of light-emitting elements on a support; Disposing an inorganic member having a void between the upper surface of the light-emitting element and between adjacent light-emitting elements; Forming a groove between adjacent light-emitting elements in the inorganic member; A method for manufacturing a light-emitting device, including disposing a covering member on an upper surface and the groove located above the light-emitting element in the inorganic member, and impregnating a part of the covering member into the void. <Aspect 2> In the step of forming the groove, the groove penetrates the inorganic member, which is the method for manufacturing a light-emitting device according to Aspect 1. <Aspect 3> After the impregnating step, the method for manufacturing a light-emitting device according to Aspect 1, including cutting the inorganic member and the covering member at the position of the groove. <Aspect 4> In the cutting step, cutting is performed using a blade having a width narrower than the groove, which is the method for manufacturing a light-emitting device according to Aspect 3. <Aspect 5> In the step of preparing the light-emitting element, the upper surface of the light-emitting element has a pair of electrodes. After the impregnating step, a step of exposing the electrode by removing the inorganic member and the coating member located above the upper surface of the light-emitting element is included. The method for manufacturing a light-emitting device according to aspect 1. <Aspect 6> In the step of exposing the electrode, the inorganic member and the coating member located above the upper surface of the light-emitting element are removed by grinding. The method for manufacturing a light-emitting device according to aspect 5. <Aspect 7> In the impregnating step, the coating member is a mixture containing polysilazane and a solvent. The method for manufacturing a light-emitting device according to aspect 1. <Aspect 8> In the step of coating the coating member, the coating member is a mixture containing inorganic particles and a solvent. The method for manufacturing a light-emitting device according to aspect 1. <Aspect 9> The inorganic member is a light-reflective member including a light-reflecting material, silicon dioxide, and an alkali metal. The method for manufacturing a light-emitting device according to any one of aspects 1 to 8.

Explanation of reference numerals

[0078] 1 Light-emitting device 11 Light-emitting surface 2 Light-emitting element 22 Electrode 23 Upper surface of the light-emitting element 24 Lower surface of the light-emitting element 3, 3a Inorganic member 33 Pore 32 Light-reflecting material 33a Void 35a Groove 36a Upper surface of the inorganic member 4 Translucent member 5 Support 6 Coating member 61 Inorganic particle 62 Solvent C Blade

Claims

1. A step of preparing a plurality of light-emitting elements each having an upper surface and a lower surface located on the opposite side of the upper surface; A step of arranging the plurality of light-emitting elements on a support; A step of arranging an inorganic member having a gap between the upper surface of the light-emitting element and between adjacent light-emitting elements; A step of forming a groove between adjacent light-emitting elements in the inorganic member; A method for manufacturing a light-emitting device, comprising: arranging a coating member on an upper surface of the inorganic member located above the light-emitting element and in the groove, and impregnating a part of the coating member into the gap.

2. The method for manufacturing a light-emitting device according to claim 1, wherein in the step of forming the groove, the groove penetrates the inorganic member.

3. The method for manufacturing a light-emitting device according to claim 1, further comprising a step of cutting the inorganic member and the coating member at the position of the groove after the impregnating step.

4. The method for manufacturing a light-emitting device according to claim 3, wherein in the cutting step, cutting is performed using a blade having a width narrower than the groove.

5. In the step of preparing the light-emitting element, the upper surface of the light-emitting element has a pair of electrodes, The method for manufacturing a light-emitting device according to claim 1, further comprising a step of exposing the electrodes by removing the inorganic member and the coating member located above the upper surface of the light-emitting element after the impregnating step.

6. The method for manufacturing a light-emitting device according to claim 5, wherein in the step of exposing the electrodes, the inorganic member and the coating member located above the upper surface of the light-emitting element are removed by grinding.

7. The method for manufacturing a light-emitting device according to claim 1, wherein in the impregnating step, the coating member is a mixture containing polysilazane and a solvent.

8. The method for manufacturing a light-emitting device according to claim 1, wherein in the step of coating the coating member, the coating member is a mixture containing inorganic particles and a solvent.

9. The method for manufacturing a light-emitting device according to any one of claims 1 to 8, wherein the inorganic member is a light-reflective member containing a light-reflective material, silicon dioxide, and an alkali metal.

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