Light-emitting device and method for manufacturing a light-emitting device

Abstract

To provide a light-emitting device capable of enhancing light extraction efficiency, and a method for manufacturing the light-emitting device.SOLUTION: A light-emitting device includes a plate-like substrate 10, a semiconductor structure layer 23 which is arranged on one main surface 10S of the substrate and includes a light-emission layer, a light-emission element 20 which is arranged on the semiconductor structure layer and includes a plate-like translucent substrate 21, a wave conversion body 40 which includes phosphor particles and is arranged on the upper surface of the translucent substrate through an adhesive resin 50, and a light scattering material 70R which is composed of a resin material containing light scattering particles, and is formed so as to cover the side face of the light-emission element and the one main surface of the substrate from the side face of the wavelength conversion body, wherein the light scattering material has a first inclined surface 70S1 which is inclined downward from the upper end of the side face of the wavelength conversion body toward the outer side, a flat surface 70S2 which is formed so as to be continuous into the first inclined surface and extends along the one main surface, and a second inclined surface 70S3 which is formed so as to be continuous into the outside end of the flat surface and is inclined upward toward the outer side, and the height position from the one main surface of the substrate of the flat surface is lower than the lower surface of the wavelength conversion body.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a light-emitting device including a semiconductor light-emitting element and a method for manufacturing the same.

Background Art

[0002] Conventionally, there has been known a light-emitting device including a substrate, a light-emitting element having a semiconductor light-emitting layer mounted on the substrate, a wavelength converter that converts the wavelength of light emitted from the light-emitting element, and a light reflector that seals a portion other than the light-emitting surface of the wavelength converter and reflects light from the light-emitting element and the wavelength converter.

[0003] For example, Patent Document 1 discloses a light-emitting device having a substrate, a light-emitting element mounted on the substrate, a light-transmitting member including a phosphor as a wavelength-converting material, and a covering member containing a light-reflective material and covering the side surfaces of the light-emitting element and the light-transmitting member.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the light-emitting device described in Patent Document 1, it is an object to reflect light from the light-emitting element and the light-transmitting member by a covering member containing a light-reflective material and emit light only from the light-emitting surface of the light-transmitting member.

[0006] ​​​​​The present invention has been made in view of the above points, and aims to provide a light-emitting device and a method for manufacturing a light-emitting device that can prevent a decrease in the total luminous flux of light emitted from the light-emitting device and improve light extraction efficiency. [Means for solving the problem]

[0008] The light-emitting device according to the present invention comprises a plate-shaped substrate, a semiconductor structural layer disposed on the main surface of the substrate and including a light-emitting layer, a light-emitting element including a plate-shaped, light-transmitting substrate disposed on the semiconductor structural layer, a wavelength converter containing phosphor particles disposed on the upper surface of the light-transmitting substrate via an adhesive resin, and a light-scattering portion made of a resin material containing light-scattering particles, formed to cover from the side surface of the wavelength converter to the side surface of the light-emitting element and the main surface of the substrate, wherein the light-scattering portion has a first inclined surface that slopes downward outward from the upper end of the side surface of the wavelength converter, a flat surface formed continuously with the first inclined surface and extending along the main surface, and a second inclined surface formed continuously with the outer end of the flat surface and sloping upward outward, wherein the height position of the flat surface from the main surface of the substrate is lower than the lower surface of the wavelength converter.

[0009] Furthermore, the method for manufacturing a light-emitting device according to the present invention includes an element bonding step of bonding a light-emitting element, which includes a semiconductor structural layer containing a light-emitting layer and a plate-shaped translucent substrate disposed on the semiconductor structural layer, to the main surface of the substrate; a wavelength converter bonding step of bonding a wavelength converter to the upper surface of the translucent substrate; a light-scattering resin coating step of applying a light-scattering resin to the main surface of the substrate; and a resin curing step of heating the light-scattering resin to form a light-scattering portion that covers from the side surface of the wavelength converter to the side surface of the light-emitting element and the main surface of the substrate, wherein the resin curing step is performed. In the process, the light scattering resin is continuously heated to a predetermined temperature in one step to form the light scattering portion, in which a first inclined surface that slopes downward toward the outward direction from the upper end of the side surface of the wavelength converter is integrally formed, a flat surface that is formed continuously with the first inclined surface and extends along the main surface of the wavelength converter, and a second inclined surface that is formed continuously with the outer end of the flat surface and slopes upward toward the outward direction, and the height position of the flat surface from the main surface of the substrate is formed to be lower than the lower surface of the wavelength converter. [Brief explanation of the drawing]

[0010] [Figure 1] This is a top view of the light-emitting device according to Embodiment 1 of the present invention. [Figure 2] This is a cross-sectional view of a light-emitting device according to Embodiment 1 of the present invention. [Figure 3] This is a bottom view of a light-emitting element used in a light-emitting device according to Embodiment 1 of the present invention. [Figure 4] This is a cross-sectional view of a light-emitting element used in a light-emitting device according to Embodiment 1 of the present invention. [Figure 5] This diagram shows the manufacturing flow of the light-emitting device according to Embodiment 1 of the present invention. [Figure 6] This is a cross-sectional view of the manufacturing process of the light-emitting device according to Embodiment 1 of the present invention. [Figure 7] This is a cross-sectional view of the manufacturing process of the light-emitting device according to Embodiment 1 of the present invention. [Figure 8] This is a cross-sectional view of the manufacturing process of the light-emitting device according to Embodiment 1 of the present invention. [Figure 9]It is a cross-sectional view during the manufacture of the light-emitting device according to Example 1 of the present invention. [Figure 10] It is a cross-sectional view during the manufacture of the light-emitting device according to Example 1 of the present invention. [Figure 11] It is a cross-sectional view during the manufacture of the light-emitting device according to Example 1 of the present invention. [Figure 12] It is a cross-sectional view of the light-emitting device of Comparative Example 1. [Figure 13] It is a cross-sectional view of the light-emitting device of Comparative Example 1. [Figure 14] It is a diagram showing the luminance distribution of the light-emitting device according to Example 1 of the present invention. [Figure 15] It is an enlarged cross-sectional view of the light-scattering portion of the light-emitting device according to Example 1 of the present invention. [Figure 16] It is a top view of the light-emitting device according to Example 2 of the present invention. [Figure 17] It is a cross-sectional view of the light-emitting device according to Example 2 of the present invention. [Figure 18] It is a top view of the light-emitting device according to Example 3 of the present invention. [Figure 19] It is a cross-sectional view of the light-emitting device according to Example 3 of the present invention. [[ID=3=2]] [Figure 20] It is a cross-sectional view of the light-emitting device according to a modified example of the present invention.

Mode for Carrying Out the Invention

[0011] Hereinafter, examples of the present invention will be described in detail. In the following description and the accompanying drawings, substantially the same or equivalent parts are denoted by the same reference numerals.

Examples

[0012] While referring to FIGS. 1 and 2, the configuration of the light-emitting device 100 according to Example 1 will be described. FIG. 1 is a top view of the light-emitting device 100 according to Example 1. Further, FIG. 2 is a cross-sectional view taken along the line A-A of the light-emitting device 100 shown in FIG. 1.

[0013] (Light-emitting device 100) The light-emitting device 100 comprises a flat substrate 10 having one main surface, a light-emitting element 20 mounted on the one main surface of the substrate 10, i.e., the upper surface 10S, a wavelength converter 40 disposed on the surface of the light-emitting element 20 opposite to the surface facing the substrate 10, i.e., the upper surface of the light-emitting element 20, and a light-scattering material 70R extending to cover the sides of the light-emitting element 20 and the sides of the wavelength converter 40 and to cover the upper surface 10S of the substrate 10. The light-emitting device 100 also comprises a frame 60 formed in the outer edge region of the upper surface 10S of the substrate 10 so as to surround the light-emitting element 20 and the wavelength converter 40.

[0014] In the following explanation, the direction of the upper surface 10S of the substrate 10 will be referred to as "up," and the direction of the lower surface will be referred to as "down."

[0015] (Circuit board 10) The substrate 10 is a flat, insulating substrate. The substrate 10 is provided with a pair of electrodes, a first electrode 15 and a second electrode 17, each formed from the upper surface 10S to the lower surface and spaced apart from each other. For example, ceramics such as aluminum nitride (AlN) and alumina (Al2O3) can be used as the base material for the substrate 10. Alternatively, alumina mixed with glass material may be used as the base material for the substrate 10. In Example 1, AlN, which has insulating properties and high thermal conductivity, was selected as the base material and used as the substrate 10.

[0016] Each of the first electrode 15 and the second electrode 17 comprises a first mounted electrode 15A and a second mounted electrode 17A formed on the upper surface 10S of the substrate 10, a first mounted electrode 15B and a second mounted electrode 17B formed on the lower surface of the substrate 10, and a first through electrode 15C and a second through electrode 17C that penetrate the substrate 10 and electrically connect the respective mounted electrode and mounted electrode. Furthermore, the first electrode 15 and the second electrode 17 are each made of a conductive metal. In Example 1, copper (Cu) was used for each of the first electrode 15 and the second electrode 17. In addition, nickel (Ni) and gold (Au) are sequentially laminated on the exposed surfaces of each of the first electrode 15 and the second electrode 17.

[0017] In Example 1, the substrate 10 and the first electrode 15 and second electrode 17 were formed using a low-temperature co-fired ceramic (LTCC) substrate, which was created by simultaneously firing a Cu electrode pattern and a ceramic substrate. Note that conductive metals other than Cu, such as tungsten (W) or silver (Ag), may be used for the first electrode 15 and second electrode 17.

[0018] The substrate 10 has an upper surface 10S on which the first mounting electrode 15A and the second mounting electrode 17A are formed, which functions as an element mounting surface for mounting the light-emitting element 20, and a lower surface on which the first mounting electrode 15B and the second mounting electrode 17B are formed, which functions as a mounting surface for mounting to a mounting substrate.

[0019] (Light-emitting element 20) The light-emitting element 20 is a semiconductor light-emitting element such as a light-emitting diode (LED) arranged on the upper surface 10S of the substrate 10. In Example 1, an LED element that emits blue light was used as the light-emitting element 20.

[0020] The light-emitting element 20 has a structure that includes a translucent plate-shaped growth substrate 21, a semiconductor structural layer 23 including a light-emitting layer formed on the lower surface of the growth substrate 21, and a pair of electrodes, a cathode electrode 25 and an anode electrode 27, formed on the surface of the semiconductor structural layer 23 opposite to the surface in contact with the growth substrate 21, i.e., the lower surface.

[0021] The light-emitting element 20 is mounted on a growth substrate 21 on which a semiconductor structural layer 23 is formed, with its lower surface facing the upper surface 10S of the substrate 10. Furthermore, the cathode electrode 25 and anode electrode 27 of the light-emitting element 20 are each bonded to a first mounting electrode 15A and a second mounting electrode 17A formed on the upper surface 10S of the substrate 10, respectively, via an element junction layer 30.

[0022] In other words, the light-emitting element 20 is a flip-chip type light-emitting element formed by inverting the surface on which the active surface, the semiconductor structural layer 23, is formed and bonding it to the substrate 10. To put it another way, the light-emitting element 20 includes a semiconductor structural layer 23 that includes a light-emitting layer and is disposed on one of the main surfaces of the substrate 10, i.e., the upper surface 10S, and a plate-shaped and translucent growth substrate 21 disposed on the semiconductor structural layer 23.

[0023] In the light-emitting element 20, light emitted from the semiconductor structural layer 23 formed on the lower surface of the growth substrate 21 passes through the growth substrate 21 and is emitted from the upper surface of the growth substrate 21. In other words, the upper surface of the growth substrate 21 functions as the light extraction surface of the light-emitting element 20.

[0024] (Structure of the light-emitting element 20) An example of the structure of the light-emitting element 20 will be explained using Figures 3 and 4. Figure 3 is a bottom view of the light-emitting element 20 used in the light-emitting device 100 according to Embodiment 1 of the light-emitting element 20. Figure 4 is a cross-sectional view of the light-emitting element 20 shown in Figure 3 along line BB. Note that only the light-emitting element 20 is shown in Figures 3 and 4.

[0025] The light-emitting element 20 is constructed by sequentially stacking an n-type semiconductor layer 23N, a gallium nitride (GaN)-based composition, an emissive layer 23E with a quantum well structure, and a p-type semiconductor layer 23P on the bottom surface 21S, which is one side of a translucent growth substrate 21 made of sapphire, respectively. In Example 1, a sapphire substrate with a thickness of approximately 70 μm was used as the growth substrate 21.

[0026] The n-type semiconductor layer 23N is formed over the entire lower surface 21S of the growth substrate 21. That is, the n-type semiconductor layer 23N is formed to cover the entire lower surface 21S of the growth substrate 21. As shown in Figures 3 and 4, the n-type semiconductor layer 23N has two convex portions 23NC on its lower surface that are spaced apart from each other and each has a rectangular planar shape. The space between these two convex portions 23NC on the lower surface of the n-type semiconductor layer 23N is a recess 23NR. The light-emitting layer 23E and the p-type semiconductor layer 23P are formed to be stacked sequentially on the lower surface of the convex portions 23NC of the n-type semiconductor layer 23N.

[0027] The p-side electrode PE is formed on the lower surface of the p-type semiconductor layer 23P and is electrically connected to the p-type semiconductor layer 23P in an ohmic connection. The n-side electrode NE is formed on the surface of the recess 23NR on the lower surface of the n-type semiconductor layer 23N and is electrically connected to the n-type semiconductor layer 23N in an ohmic connection.

[0028] The first insulating layer IN1 is formed on the surface of the semiconductor structure layer 23, which consists of an n-type semiconductor layer 23N, an emissive layer 23E, and a p-type semiconductor layer 23P, so as to expose at least a portion of the lower surfaces of the p-side electrode PE and the n-side electrode NE.

[0029] The p-side connecting wire PW is formed from the exposed surface of the p-side electrode PE of the first insulating layer IN1 to the surface of the first insulating layer IN1 formed on the inner surface of the recess 23NR.

[0030] The second insulating layer IN2 is formed to cover the first insulating layer IN1 and the p-side connecting wire PW. The second insulating layer IN2 has an opening in the portion below one of the protrusions 23NC (the left protrusion 23NC in Figure 4) that exposes the lower surface of the p-side connecting wire PW.

[0031] The n-side connecting wire NW is formed from the lower surface of the n-side electrode NE to the lower surface of the second insulating layer IN2 located below the other protrusion 23NC (the right-side protrusion 23NC in Figure 4).

[0032] The third insulating layer IN3 is formed to cover the n-side junction wiring NW. The third insulating layer IN3 is formed so that the surface of the n-side junction wiring NW is exposed below the other protrusion 23NC (the protrusion 23NC on the right side in Figure 4).

[0033] The cathode electrode 25 is formed on the lower surface of the n-side connecting wiring NW that is exposed below the other protrusion 23NC of the n-type semiconductor layer 23N. The anode electrode 27 is formed on the lower surface of the p-side connecting wiring PW that is exposed below one of the protrusions 23NC (the left protrusion 23NC in Figure 4) of the n-type semiconductor layer 23N.

[0034] The anode electrode 27 is electrically connected to the p-side connecting wire PW, and is electrically connected to the p-type semiconductor layer 23P via the p-side connecting wire PW. The cathode electrode 25 is electrically connected to the n-side connecting wire NW, and is electrically connected to the n-type semiconductor layer 23N via the n-side connecting wire NW.

[0035] The p-side electrode PE described above is, for example, an ohmic electrode layer containing an ITO (Indium Tin Oxide) layer and a light-reflective electrode layer containing a layer of silver (Ag) or rhodium (Rh). The p-side connecting wiring PW and n-side connecting wiring NW are, for example, light-reflective wiring layers of aluminum (Al). The first insulating layer IN1 to the third insulating layer IN3 are, for example, translucent insulating layers of silicon oxide (SiO2). The p-side electrode PE, p-side connecting wiring PW, and n-side connecting wiring NW function as conductive light-reflective layers that reflect light emitted from the light-emitting layer 23E towards the growth substrate 21. In other words, the light-emitting element 20 has a pair of electrodes, a cathode electrode 25 and an anode electrode 27, on the underside of the semiconductor structure layer 23, and has the p-side electrode PE, p-side connecting wiring PW, and n-side connecting wiring NW, which function as conductive light-reflective layers, between the semiconductor structure layer 23 and the cathode electrode 25 and anode electrode 27.

[0036] In Example 1, a light-emitting device 100 was manufactured using a light-emitting element 20 having the structure described above. Note that the structure of the light-emitting element 20 described above is merely one example.

[0037] (Element junction layer 30) Refer again to Figures 1 and 2.

[0038] As described above, the light-emitting element 20 is positioned on the upper surface 10S of the substrate 10 such that the lower surface 21S on which the semiconductor structure layer 23 of the growth substrate 21 is formed faces the upper surface 10S of the substrate 10. Furthermore, the cathode electrode 25 and anode electrode 27 of the light-emitting element 20 are bonded to the first mounting electrode 15A and the second mounting electrode 17A of the substrate 10 via the element junction layer 30.

[0039] The element junction layer 30 is conductive and is a junction layer that joins the first mounting electrode 15A and the second mounting electrode 17A of the substrate 10 to the cathode electrode 25 and the anode electrode 27 of the light-emitting element 20, respectively. In Example 1, a gold-tin (AuSn) eutectic layer was used for the element junction layer 30 to bond the light-emitting element 20. As a result, the first mounting electrode 15B functions as the cathode electrode of the light-emitting device 100, and the second mounting electrode 17B functions as the anode electrode of the light-emitting device 100.

[0040] As another example, solder paste or silver paste can be used for the element junction layer 30, and can be appropriately selected depending on the bonding material used with the mounting substrate when mounting the light-emitting device 100.

[0041] (Wavelength converter 40) The wavelength converter 40 has a plate-like shape and is bonded to the upper surface of the light-emitting element 20 via an adhesive layer 50. The wavelength converter 40 converts a portion of the light emitted from the light-emitting element 20, which enters from the lower surface opposite the light-emitting element 20, and emits the light from the upper surface 40T.

[0042] The wavelength converter 40 is made of, for example, a polycrystalline ceramic sintered body obtained by mixing phosphor particles and ceramic particles, which act as a binder, and then firing them. The wavelength converter 40 also has light scattering properties, which scatter light that enters the interior and light that is generated inside at the crystal grain interface. In this embodiment, the wavelength converter 40 is adjusted to scatter light that enters from one side while mainly emitting light from the other opposing side.

[0043] With this wavelength converter 40, light emitted from the light-emitting element 20 enters the wavelength converter 40 from the bottom surface (incoming surface), diffuses forward, and is emitted from the top surface 40T (outgoing surface). In contrast, the light whose wavelength has been converted by the phosphor particles contained in the wavelength converter 40 is mainly emitted from both the top and bottom surfaces of the wavelength converter 40. Of this, the light emitted from the bottom surface of the wavelength converter 40 enters the light-emitting element 20 from the top surface, is reflected by the p-side electrode PE, p-side connecting wiring PW, and n-side connecting wiring NW, which are also the light reflection layers of the light-emitting element 20, is emitted again from the top surface of the light-emitting element 20, enters the wavelength converter 40 from the bottom surface, and is finally emitted from the top surface 40T of the wavelength converter 40. In addition, an amount of light corresponding to the scattering properties is emitted from the sides of the wavelength converter 40.

[0044] In Example 1, yttrium aluminum garnet (YAG:Ce, Y3Al5O) doped with cerium (Ce) was used as the phosphor particles of the wavelength converter 40. 12 A wavelength converter 40 was manufactured using crystalline

[0045] (Adhesive layer 50) The adhesive layer 50 is a translucent resin that adheres the upper surface, which is the light-emitting surface of the light-emitting element 20, to the lower surface, which is the light-receiving surface of the wavelength converter 40. In Example 1, a translucent thermosetting silicone resin was used as the adhesive layer 50. In addition to silicone resin, epoxy resin or acrylic resin can also be used for the adhesive layer 50.

[0046] In Example 1, the adhesive layer 50 is formed between the upper surface of the light-emitting element 20 and the wavelength converter 40 to a thickness of approximately 10 μm.

[0047] (Frame 60) The frame 60 is formed in an annular shape on the upper surface 10S of the substrate 10, surrounding the light-emitting element 20 and the wavelength converter 40. The frame 60 is made of, for example, a resin material that is reflective to the light emitted from the light-emitting element 20 and the wavelength converter 40. Furthermore, the height of the frame 60 is equal to or higher than the height of the upper surface 40T of the wavelength converter 40 so that the light emitted from the light-emitting element 20 and the wavelength converter 40 can be emitted in front of the light-emitting device 100. In Example 1, a thermosetting silicone resin mixed with titanium dioxide (TiO2) particles, which are light-scattering particles with a particle size of 200 nm to 300 nm, was used as the frame 60. In Example 1, a silicone resin containing approximately 60 to 80 wt% TiO2 particles was used to form the frame 60. The frame 60 can also be integrally molded with the substrate 10. In that case, the frame 60 is made of the same material as the substrate 10.

[0048] (Light scattering section 70) The light scattering portion 70 is formed within a region surrounded by the frame 60 on the upper surface 10S of the substrate 10.

[0049] As shown in Figure 2, the light scattering section 70 is formed from a light scattering material 70R that exposes the upper surface 40T of the wavelength converter 40, integrally covering the surface from the upper end of the side surface of the wavelength converter 40 (the outer edge of the upper surface 40T) to the upper surface 10S of the substrate 10 and the upper end of the inner surface of the frame 60, and having an open top, and a concave space CA surrounded by the light scattering material 70R and open to the top.

[0050] The light scattering material 70R is a resin material that contains, for example, light-scattering particles and scatters the light emitted from the light-emitting element 20 and the wavelength converter 40. In Example 1, a thermosetting silicone resin mixed with TiO2 particles, which are light-scattering particles having a particle size of 200 nm to 300 nm, was used as the light scattering material 70R. In Example 1, the light scattering material 70R was formed using a silicone resin containing approximately 8 to 30 wt% TiO2 particles.

[0051] The light scattering material 70R has a first inclined surface 70S1 that slopes downward outward from the upper end of the side surface of the wavelength converter 40. The light scattering material 70R also has a flat surface 70S2 that is continuous with the first inclined surface 70S1 and extends along the upper surface 10S of the substrate 10, substantially parallel to the upper surface 10S. The light scattering material 70R also has a second inclined surface 70S3 that is continuous with the flat surface 70S2 and slopes upward toward the upper end of the inner surface of the frame 60, that is, slopes upward outward. Space CA is the space enclosed by the first inclined surface 70S1, the flat surface 70S2, and the second inclined surface 70S3.

[0052] In Example 1, the maximum thickness of the portion of the light scattering material 70R that covers the sides of the light-emitting element 20 and the wavelength converter 40 is approximately 3 to 4 μm from the sides of the light-emitting element 20 and the wavelength converter 40. Also, the maximum thickness of the portion of the light scattering material 70R that covers the inner surface of the frame 60 is approximately 5 to 10 μm from the inner surface of the frame 60.

[0053] Light emitted from the side of the light-emitting element 20 and light emitted from the side of the wavelength converter 40 scatters inside the light-scattering material 70R, reaches the first inclined surface 70S1, and is emitted into space CA from there, and is emitted upward from the opening of the light-scattering section 70.

[0054] Therefore, in the light-emitting device 100 according to Example 1, it is possible to extract light from space CA as well. That is, in a top view, the region surrounded by the frame 60 functions as the light extraction surface in the light-emitting device 100 according to Example 1. Therefore, the area of ​​the light extraction surface can be increased in the light-emitting device 100, and the total luminous flux of the light emitted from the light-emitting device 100 can be improved. In this example, the area of ​​the light scattering section 70 in a top view is about 8 times the upper surface 40T of the wavelength converter 40. The area of ​​the light scattering section 70 is preferably about 4 to 12 times that of the wavelength conversion member 40. If it is less than 3 times, the inclination of the first inclined surface 70S1 becomes gentler, and the amount of light emitted into space CA decreases. If it is more than 10 times, the area of ​​space CA may become too large and dark. Furthermore, the shape is preferably a similarly enlarged shape of the outer periphery of the stacked light-emitting element 20 and the wavelength converter 40.

[0055] Furthermore, it is preferable that the height position of the flat surface 70S2 of the light scattering material 70R is at least half the thickness of the growth substrate 21 relative to the height of the upper surface of the growth substrate 21, so that sufficient light is emitted from the space CA. In this embodiment, since the thickness of the growth substrate 21 is about 70 μm, it is preferable that the height position of the flat surface 70S2 of the light scattering material 70R is at least 35 μm lower than the upper surface of the growth substrate 21.

[0056] Furthermore, it is more preferable that the height position of the flat surface 70S2 of the light scattering material 70R is at least 2 / 3 of the thickness of the growth substrate 21 relative to the height of the upper surface of the growth substrate 21. In this embodiment, it is more preferable that the height position of the flat surface 70S2 is at least 47 μm lower than the upper surface of the growth substrate 21.

[0057] Furthermore, it is preferable that the height of the flat surface 70S2 of the light scattering material 70R is higher than the upper surface of the semiconductor structural layer 23, i.e., the lower surface 21S of the growth substrate 21. This is because if the height of the flat surface 70S2 of the light scattering material 70R is lower than the lower surface 21S of the growth substrate 21, the proportion of blue light passing through the light scattering material 70R from the semiconductor structural layer 23 will increase.

[0058] (Method for manufacturing the light-emitting device 100) Next, the manufacturing method of the light-emitting device 100 of Example 1 will be described using Figures 5 to 11.

[0059] Figure 5 is a diagram showing the manufacturing flow of the light-emitting device 100 according to Embodiment 1 of the present invention. Figures 6 to 11 show cross-sectional views of the light-emitting device 100 at each step of the manufacturing procedure shown in Figure 5. In Figures 6 to 11, the cross-section is shown along line AA shown in Figure 1.

[0060] First, as shown in Figure 6, a step is performed to prepare a substrate 10 on which the first electrode 15 and the second electrode 17 are formed (step S11, substrate preparation step). In this step, Cu electrode patterns of the first electrode 15 and the second electrode 17 are formed in the through-holes, the upper surface 10S and the lower surface of an AlN slurry sheet with through-holes, and then fired (low-temperature simultaneous firing). After that, Ni plating and Au plating are applied to the Cu electrode patterns to form the substrate 10.

[0061] Next, as shown in Figure 7, a step is performed to bond the light-emitting element 20 to the upper surface 10S of the substrate 10 (step S12, element bonding step). In this step, first, a paste made of AuSn particles and flux, which is the raw material for the element bonding layer 30, is applied to the upper surfaces of the first mounting electrode 15A and the second mounting electrode 17A. Next, the light-emitting element 20 is placed on the substrate 10 such that the cathode electrode 25 and anode electrode 27 of the light-emitting element 20 face the first mounting electrode 15A and the second mounting electrode 17A, respectively, via the paste.

[0062] Subsequently, the substrate 10 in this state is heated to approximately 300°C in a reflow oven to melt the AuSn particles of the paste applied on the first mounting electrode 15A and the second mounting electrode 17A and to cause a eutectic reaction, thereby forming an element bonding layer 30 that bonds each electrode of the light-emitting element 20 to each mounting electrode of the substrate 10.

[0063] Next, as shown in Figure 8, a step of bonding the wavelength converter 40 to the upper surface of the light-emitting element 20 is performed (Step S13, Wavelength Converter Bonding Step). In this step, first, an uncured liquid silicone resin, which is the raw material for the adhesive layer 50, is applied to the upper surface of the light-emitting element 20. Next, the wavelength converter 40 is placed so that it is in contact with the silicone resin and pressed toward the upper surface of the light-emitting element 20. The wavelength converter 40 is placed so that, when viewed from above, the outer shapes of the wavelength converter 40 and the light-emitting element 20 are approximately the same.

[0064] Subsequently, the substrate 10 in this state is heated at 170°C for 10 minutes to partially cure the silicone resin. The silicone resin may be fully cured in this step, or it may be left uncured and cured simultaneously when the frame 60 is formed as described later.

[0065] Next, as shown in Figure 9, a step of forming a frame 60 on the upper surface 10S of the substrate 10 is performed (step S14, frame formation step). In this step, first, using a dispenser filled with uncured silicone resin containing dispersed TiO2 particles, which is the raw material for the frame 60, the raw material for the frame 60 is drawn on the upper surface 10S of the substrate 10 so as to surround the light-emitting element 20 and the wavelength converter 40.

[0066] Subsequently, the substrate 10 in this state is heated at 150°C for 60 minutes to cure the silicone resin and form the frame 60. Alternatively, the molded frame 60 may be bonded with silicone resin. In this case, this is performed simultaneously in step 13 described above. Furthermore, if a substrate 10 with the frame 60 already provided is used, the frame formation step can be omitted.

[0067] Next, as shown in Figure 10, a step is performed to coat the region surrounded by the frame 60 on the upper surface 10S of the substrate 10 with light scattering resin 70M, which is the raw material for the light scattering material 70R (step S15, light scattering resin coating step). In this step, the light scattering resin 70M is coated between the light-emitting element 20 and the frame 60 using a dispenser filled with uncured silicone resin in which TiO2 particles are dispersed, which is the light scattering resin 70M.

[0068] The amount of light-scattering resin 70M applied is adjusted so that after the silicone resin hardens, the light-scattering material 70R takes on the shape described above, and in particular, the height of the flat surface 70S2 of the light-scattering material 70R is lower than the upper surface of the light-emitting element 20. Note that, if the frame 60 is light-reflective, the edges of the light-scattering resin 70M do not need to completely extend up to the upper edge of the side surface of the wavelength converter 40 and the upper edge of the inner surface of the frame 60 during application.

[0069] Next, as shown in Figure 11, a step is performed to cure the light scattering resin 70M to form the light scattering material 70R (step S16, light scattering resin curing step). In this step, the substrate 10 coated with the light scattering resin 70M is heated at 150°C for 60 minutes to cure the silicone resin and form the light scattering material 70R.

[0070] In this step, the substrate 10 coated with the light-scattering resin 70M is rapidly heated so that the edges of the light-scattering resin 70M completely climb up to the upper edge of the side surface of the wavelength converter 40 and the upper edge of the inner surface of the frame 60.

[0071] Typically, when heat-curing silicone resin, the resin is preheated for about 30 minutes by raising the temperature from room temperature to 100°C in a heating furnace, for example, and then further heated to 150°C for about 30 minutes to achieve complete curing.

[0072] In Example 1, without performing the above-mentioned preheating, the light-scattering resin 70M is heated from room temperature to 150°C in a heating furnace or the like for 60 minutes to completely cure. That is, the light-scattering resin 70M is cured by continuously heating it to a predetermined temperature in one step.

[0073] This allows the edges of the light-scattering resin 70M to completely creep up to the upper edge of the side surface of the wavelength converter 40 and the upper edge of the inner surface of the frame 60. Specifically, the uncured silicone resin contained in the light-scattering resin 70M expands while its viscosity decreases at around 100°C, and then hardens while shrinking in volume as a cross-linked structure of the silicone resin is formed. In Example 1, by heating from room temperature to 150°C in one step, the edges of the uncured silicone resin contained in the light-scattering resin 70M can be made to creep up to the side surface of the wavelength converter 40 and the side surface of the frame 60, and hardened into the light-scattering material 70R while maintaining that creeping position. This makes it possible to form a light-scattering portion 70 consisting of a light-scattering material 70R that integrally covers the surface from the upper edge of the side surface of the wavelength converter 40 to the upper surface 10S of the substrate 10 and the upper edge of the side surface of the frame 60, and a concave space CA surrounded by the surface of the light-scattering material 70R and open at the top.

[0074] In this step, for example, the substrate 10 coated with light-scattering resin 70M may be placed in a heating furnace that is maintained at 150°C and operated continuously for a predetermined time.

[0075] By performing the above steps S11 to S16, the light-emitting device 100 of Example 1 was manufactured.

[0076] (Introduction to the comparative example) Next, Comparative Examples 1 and 2 will be described. Comparative Examples 1 and 2 are similar to Example 1 except for a few points, so only the differences will be explained.

[0077] Figure 12 is a cross-sectional view of the light-emitting device 200 as Comparative Example 1. Also, Figure 12 is a cross-sectional view of the light-emitting device 100 shown in Figure 1 at a position corresponding to line AA.

[0078] Figure 13 is a cross-sectional view of the light-emitting device 300 as comparative example 2. Also, Figure 13 is a cross-sectional view of the light-emitting device 100 shown in Figure 1 at a position corresponding to line AA.

[0079] The light-emitting device 200 of Comparative Example 1 and the light-emitting device 300 of Comparative Example 2 use the same substrate 10, light-emitting element 20, wavelength converter 40, and frame 60 as those used in the light-emitting device 100 of Example 1.

[0080] (Comparative Example 1) In Comparative Example 1, the light-emitting device 200 is configured such that the height of the bottom surface (flat surface) of the concave space CB of the light-scattering section 70 is approximately the same as the height of the top surface 40T of the wavelength converter 40. More specifically, the height DB of the bottom surface of the concave space CB of the light-scattering section 70 is set to be approximately 63 μm lower in the direction of the substrate 10 from the top surface 40T of the wavelength converter 40.

[0081] Such a light-emitting device 200 can be manufactured by increasing the amount of light-scattering resin 70M filled in step S15 described above. The height offset DB is caused by resin shrinkage due to volume contraction during heat curing of the light-scattering resin 70M, which is a precursor of the light-scattering material 70R.

[0082] (Comparative Example 2) In the light-emitting device 300 of Comparative Example 2, the height of the bottom surface (flat surface) of the concave space CC of the light-scattering section 70 is higher than the bottom surface of the wavelength converter 40 and lower than the top surface. Specifically, the height DC of the bottom surface of the concave space CB of the light-scattering section 70 is set to a position approximately 140 μm lower from the top surface 40T of the wavelength converter 40 in the direction of the substrate 10. Such a light-emitting device 300 can be manufactured by slightly increasing the amount of light-scattering resin 70M filled in step S15 described above.

[0083] (Experimental results of Example 1 and Comparative Example) Next, the light output characteristics of the light-emitting device 100 of Example 1 will be described in comparison with the light-emitting device 200 of Comparative Example 1 and the light-emitting device 300 of Comparative Example 2.

[0084] Figure 14 shows the luminescence brightness distribution of the light-emitting device 100 of Example 1, the light-emitting device 200 of Comparative Example 1, and the light-emitting device 300 of Comparative Example 2, as viewed from above.

[0085] The horizontal axis of Figure 14 shows the distance from reference point 0 in the direction along line AA shown in Figure 1. The reference point 0, indicated by a dashed line on the horizontal axis of Figure 14, is the center point of the light extraction surface of each light-emitting device 100, 200, and 300 (the center of the upper surface 40T of the wavelength converter 40). Furthermore, within the regions indicated by dashed lines on the horizontal axis of Figure 14, the wavelength converter region represents the area from the outer edge of the upper surface 40T of each wavelength converter 40 inward, and the frame region represents the area from the inner surface of each frame 60 outward. The light scattering material region represents the formation region of the light scattering material 70R in each light-emitting device in a top view. That is, the light scattering material region represents the areas where spatial CA, CB, and CC are formed in a top view of each light-emitting device.

[0086] Furthermore, the vertical axis of Figure 14 shows the luminance values ​​of the light measured vertically downwards from above each of the light-emitting devices 100, 200, and 300 at each position shown on the horizontal axis, normalized by the luminance values ​​of Comparative Example 1 (the relative intensity relationships between them are maintained).

[0087] In Figure 14, the solid line graph shows the luminance distribution of light-emitting device 100, the dashed line graph shows the luminance distribution of light-emitting device 200, and the white dashed line graph shows the luminance distribution of light-emitting device 300.

[0088] In Example 1, the luminance ratio of the wavelength converter region, which is the upper surface 40T of the wavelength converter 40, was approximately 0.8, and the luminance ratio of the light scattering material region, which is the spatial CA region from the outer end of the upper surface 40T of the wavelength converter 40 to the inner surface of the frame 60, was 0.05 to 0.1.

[0089] In contrast, in the light-emitting device 200 of Comparative Example 1 and the light-emitting device 300 of Comparative Example 2, the luminance ratio of the wavelength converter region, which is the upper surface 40T region of the wavelength converter 40, was approximately 1.0 in both cases. Furthermore, the luminance ratio of the light-scattering material region, i.e., the spatial CB and CC regions, was approximately 0, indicating that no light was emitted. In addition, in Comparative Example 1 and Comparative Example 2, no difference in luminance ratio was observed due to the heights DB and DC of the bottom surfaces of the spatial CB and CC of the concave light-scattering portion 70 from the upper surface 40T of the wavelength converter 40.

[0090] Next, the total luminous flux of each light-emitting device will be described. The total luminous flux will be described as a percentage normalized by the total luminous flux of Comparative Example 1. The total luminous flux of light-emitting device 100 in Example 1 was 105%, while the total luminous fluxes of light-emitting device 200 in Comparative Example 1 and light-emitting device 300 in Comparative Example 2 were 100% and 101%, respectively.

[0091] As described above, the luminance ratio of the wavelength converter region in the light-emitting device 100 of Example 1 is lower than that of Comparative Examples 1 and 2, while the luminance ratio of the light-scattering material region is higher. Conversely, the total luminous flux of Example 1 is greater than that of Comparative Examples 1 and 2. In other words, the light-emitting device 100 of Example 1 is a light-emitting device that can suppress the luminance of the wavelength converter region while improving the total luminous flux. To put it another way, it is a light-emitting device that uses a light-scattering material region in addition to the wavelength converter region as the light-emitting surface.

[0092] (Regarding the light output path of the light-emitting device 100) Next, using Figure 15, the optical path of the light emitted from the light-emitting device 100 of Example 1, which has the luminance distribution and total luminous flux described above, will be explained.

[0093] Figure 15 shows the optical paths of light rays LM1 to LM6, which are part of the light generated inside the light-emitting device 100, in an enlarged cross-section of the area CA surrounding the light-emitting device 100. Note that Figure 15 is an enlarged cross-sectional view of the cross-section shown by line AA in Figure 1. Furthermore, for the sake of simplicity, only representative light rays LM1 to LM6 are schematically shown.

[0094] As described above, the light scattering material 70R exposes the upper surface 40T of the wavelength converter 40 and integrally covers the surface from the upper end of the side surface of the wavelength converter 40 to the upper surface 10S of the substrate 10 and the upper end of the side surface of the frame 60.

[0095] In the following explanation, the portion of the light scattering material 70R that covers the sides of the wavelength converter 40 and the sides of the light-emitting element 20 will be referred to as the first light scattering portion 70R1, the portion that extends onto the upper surface 10S of the substrate 10 will be referred to as the second light scattering portion 70R2, and the portion that covers the inner surface of the frame 60 will be referred to as the third light scattering portion 70R3.

[0096] Furthermore, in the following description, the surface of the first light scattering portion 70R1 that is inclined toward the substrate 10 from the upper end of the side surface of the wavelength converter 40 will be referred to as the first inclined surface 70S1, the surface of the second light scattering portion 70R2 that extends along the upper surface 10S of the substrate 10 will be referred to as the flat surface 70S2, and the surface of the third light scattering portion 70R3 that is inclined toward the upper end of the inner surface of the frame 60 will be referred to as the second inclined surface 70S3.

[0097] The first light scattering portion 70R1 is formed such that the thickness of the light scattering material 70R from the upper end of the side surface of the wavelength converter 40 and the side surface of the light-emitting element 20 gradually increases downward.

[0098] Light LM1 represents the light (converted light) that was emitted in all directions as yellow fluorescence after absorbing the blue light emitted from the light-emitting element 20, and which reached the side surface of the growth substrate from the light emitted below the wavelength converter 40.

[0099] Light LM1 enters the first light scattering portion 70R1 from the side of the growth substrate 21 of the light-emitting element 20. The light LM1 that enters the first light scattering portion 70R1 is divided into reflected light LM1A, which is reflected by the first light scattering portion 70R1 and re-enters the interior of the growth substrate 21, and transmitted light LM1B, which passes through the interior of the first light scattering portion 70R1 while scattering.

[0100] The reflected light LM1A is reflected upward by the p-side electrode PE, p-side connecting wiring PW, and n-side connecting wiring NW, which are also the light-reflecting layers of the light-emitting element 20. The transmitted light LM1B is reflected by the light-scattering member 70R and emitted upward from space CA towards the light-emitting device 100.

[0101] Light LM2 is the light that reaches the side surface of the growth substrate 21, which is the light emitted from the semiconductor light-emitting layer 23 and the reflected light LM1A that is reflected by the light-reflecting layer of the light-emitting element 20.

[0102] Light LM2 enters the first light scattering portion 70R1 from the side of the growth substrate 21 of the light-emitting element 20. The light LM2 that enters the first light scattering portion 70R1 is reflected by the first light scattering portion 70R1 and splits into reflected light LM2A and transmitted light LM2B that passes through the interior of the first light scattering portion 70R1 while scattering.

[0103] The reflected light LM2A enters the wavelength converter 40 and propagates upward. The transmitted light LM2B is reflected by the light scattering member 70R and emitted from space CA upward towards the light-emitting device 100.

[0104] The aforementioned light LM1 and light LM2 are high-intensity light that guides light from various points on the lower surface of the wavelength converter 40 and the upper surface of the semiconductor structural layer 23 to the non-scattering and translucent growth substrate 21 and reaches the side surface of the growth substrate 21. Therefore, the light intensity of the transmitted light LM1B and LM2B is also high.

[0105] Light LM3 is the light that reaches the side of the light-scattering wavelength converter 40 from the vicinity of the side surface. Light LM3 enters the first light-scattering portion 70R1 from the side surface of the wavelength converter 40 and splits into reflected light LM3A and transmitted light LM3B.

[0106] The reflected light LM3A re-enters the inside of the wavelength converter 40 and propagates upward.

[0107] Furthermore, the transmitted light LM3B is reflected by the light scattering member 70R and emitted from space CA upwards to the light-emitting device 100.

[0108] Light LM3 is low in intensity because it can reach the side of the wavelength converter 40 through scattering (lower in intensity than light LM1 and light LM2). The illustrated light LM3 is just one example; there is light that enters the side of the wavelength converter 40 from various other directions. Therefore, some of the reflected light LM3A and transmitted light LM3B also travel downwards.

[0109] Light LM4 is light that is reflected by the second inclined surface 70S3 of the light scattering portion 70R and emitted upward from the light-emitting device 100. The illustrated light LM4 is just one example; similar light exists on various other surfaces of the light scattering member 70R.

[0110] Light LM5 is the light emitted from the surface 40T of the wavelength converter 40, which is part of the light emitted from the semiconductor light-emitting element 20 and the light emitted from the phosphor of the wavelength converter 40, and is the main light of the light-emitting device 100.

[0111] Light LM6 is light emitted from the side of the semiconductor light-emitting element 20 and the wavelength converter 40, passing through the first light scattering section 70R1 and exiting from space CA, and is a secondary light source of the light-emitting device 100.

[0112] The light-emitting device 100 of Example 1 includes a non-scattering and light-transmitting growth substrate 21, a light-emitting element 20 having a light-reflective electrode layer on the lower surface of a conductive structural layer 23, and a light-scattering wavelength converter 40 containing a phosphor positioned above the growth substrate 21. This generates high-intensity light LM1 extending from the lower surface of the light converter to the side surface of the growth substrate 21, and high-intensity light LM2 extending from the upper surface of the semiconductor structural layer 23 to the side surface of the growth substrate 21.

[0113] Furthermore, by making the height of the flat surface 70S2 of the second light scattering portion 70R2 of the light scattering material 70 lower than the lower surface of the wavelength converter 40, the first light scattering portion 70R1 is structured to reach the side surface of the growth substrate 21. As a result, the transmitted light LM1B and LM2B are extracted from the surface 70S1 of the first light scattering portion 70R1 into space CA. At the same time, the transmitted light LM1B and LM2B form a reflective surface made of the light scattering material 70 that can emit light onto the upper surface of the light-emitting device 100.

[0114] Thus, the light-emitting device 100, which has a space CA that serves as a light-emitting surface in the light-scattering section 70, can extract transmitted light LM1B, LM2B, LM3B, and reflected light LM4, which are a portion of the light emitted from the semiconductor light-emitting element 20 and the wavelength converter 40, as light LM6 from space CA. Furthermore, by extracting light LM6, it is possible to reduce the brightness of light LM5 emitted from the upper surface 40T of the wavelength converter 40. [Examples]

[0115] Next, the light-emitting device 100 of Example 2 will be described. Figure 16 is a top view of the light-emitting device 100A according to Example 2. Figure 17 is a cross-sectional view of the light-emitting device 100A shown in Figure 16 along the CC line.

[0116] The light-emitting device 100A has multiple light-emitting elements 20 and wavelength converters 40 arranged on the upper surface 10AS of the substrate 10A. Except for the frame 60A, all components of the light-emitting device 100A are the same as those used in Example 1. Furthermore, the material used for the frame 60A is the same as that used for the frame 60 in Example 1.

[0117] Note that in Figure 16, the first electrode 15 and the second electrode 17 of the substrate 10A, the semiconductor structure layer 23, cathode electrode 25 and anode electrode 27 of the light-emitting element 20, the element junction layer 30 and the adhesive layer 50 are omitted from the illustration.

[0118] In Example 2, the light-emitting element 20 and the wavelength converter 40 will be described as a light-emitting element structure 80 comprising one light-emitting element 20 and one wavelength converter 40 disposed on the upper surface of the one light-emitting element 20 via an adhesive layer 50.

[0119] Multiple light-emitting elements 80 are arranged in an array on the upper surface 10AS of the substrate 10A, with predetermined intervals between them. Furthermore, an annular frame 60A is formed on the upper surface 10AS of the substrate 10A, collectively surrounding the array of multiple light-emitting elements 80.

[0120] Furthermore, a first electrode 15 and a second electrode 17 (not shown) are formed on the substrate 10A, and a wiring pattern is formed between the first mounting electrode 15B and the second mounting electrode 17B so that multiple light-emitting structures 80 are connected to each other in series or in parallel. The substrate 10A may be a single-layer substrate having mounting electrodes formed on the upper surface 10AS, mounting electrodes formed on the lower surface, and through electrodes connecting the mounting electrodes, or it may be a multilayer substrate with an intermediate wiring layer formed thereon.

[0121] Furthermore, a light scattering section 73 is formed between each of the adjacent light-emitting element structures 80. The light scattering section 73 consists of a light scattering material 73R that integrally covers the surface from the upper end of the side surface of one of the multiple light-emitting element structures 80 to the upper end of the side surface of another light-emitting element structure 80 arranged adjacent to the first light-emitting element structure 80, and which is open at the top, and a concave space CD that is surrounded by the surface of the light scattering material 73R and is open at the top. That is, the light scattering material 73R is formed to have a surface shape similar to the light scattering material 70R of Embodiment 1, from the upper end of the side surface of one light-emitting element structure 80 to the upper end of the side surface of another light-emitting element structure 80 arranged adjacent to the first light-emitting element structure 80.

[0122] Therefore, the light scattering material 73R has a first inclined surface 73S1 that slopes downward outward from the upper end of the side surface of one light-emitting element structure 80. The light scattering material 73R also has a flat surface 73S2 that is formed continuously with the first inclined surface 73S1 and extends along the upper surface 10AS of the substrate 10A. The light scattering material 73R also has a second inclined surface 73S3 that is formed continuously with the outer end of the flat surface 73S2 and slopes upward toward the upper end of the side surface of another light-emitting element structure 80 that is opposite to the side surface of one light-emitting element structure 80, i.e., slopes upward outward.

[0123] Furthermore, the inclined surface of the light scattering material 73R formed between each adjacent light-emitting element structure 80 and each of the side surfaces of the adjacent light-emitting element structures 80 can be either a first inclined surface 73S1 or a second inclined surface 73S3.

[0124] In the light-emitting device 100A of Example 2, a light-scattering material 73R having the same shape as the light-scattering material 70R of Example 1 is formed between each of the adjacent light-emitting element structures 80 and between the light-emitting element structures 80 and the frame 60A.

[0125] Therefore, the light-emitting device 100A of Example 2 can achieve the same effects as the light-emitting device 100 of Example 1, preventing a decrease in the total luminous flux of the light emitted from the light-emitting device 100A and improving the light extraction efficiency.

[0126] In other words, in the light-emitting device 100A of Example 2, the light emitted from the side of the light-emitting element 20 and the light emitted from the side of the wavelength converter 40 scatters inside the light-scattering material 73R, reaches the first inclined surface 73R1, and is emitted into space CD from there, and radiated upward from the opening of the light-scattering material 70R.

[0127] The light-emitting device 100A of Example 2 can be manufactured using the same manufacturing method as the light-emitting device 100 of Example 1. The differences in the manufacturing method of the light-emitting device 100A compared to the light-emitting device 100 of Example 1 will be explained below.

[0128] As shown in Figure 16, multiple light-emitting elements 80 are arranged in an array on the upper surface 10AS of the substrate 10A (steps S12 and S13 in Figure 5, element bonding process and wavelength converter bonding process).

[0129] Next, a frame 60A is formed on the upper surface 10AS of the substrate 10A so as to surround the multiple light-emitting element structures 80 arranged in an array (step S14 in Figure 5, frame formation step). In this step, first, the raw material resin for the frame 60A is drawn onto the substrate 10A using a dispenser filled with the raw material resin for the frame 60A so as to surround the multiple light-emitting element structures 80. Then, the substrate 10A in this state is heated to form the frame 60A.

[0130] Next, the raw resin for the light scattering material 73R is applied between each of the multiple light-emitting element structures 80 and between the light-emitting element structures 80 and the frame 60A (step S15 in Figure 5, light scattering resin application step). In this step, the raw resin for the light scattering material 73R is applied between each of the multiple light-emitting element structures 80 and between the light-emitting element structures 80 and the frame 60A using a dispenser filled with the raw resin for the light scattering material 73R.

[0131] Next, as shown in Figure 17, the substrate 10A coated with the raw resin of the light scattering material 73R is heated to cure the raw resin of the light scattering material 73R (step S16 in Figure 5, light scattering resin curing step). In this step, the raw resin of the light scattering material 73R is continuously heated to a predetermined temperature in one step, thereby forming a light scattering material 73R having a first inclined surface 73S1, a flat surface 73S2, and a second inclined surface 73S3, and a concave space CD surrounded by each of these surfaces and open at the top, between each of the adjacent light-emitting element structures 80 and between the light-emitting element structures 80 and the frame 60A.

[0132] Based on the above, the light-emitting device 100A of Example 2 can be manufactured using the same manufacturing method as the light-emitting device 100 of Example 1. [Examples]

[0133] Next, the light-emitting device 100B of Example 3 will be described. Figure 18 is a top view of the light-emitting device 100B according to Example 3. Figure 19 is a cross-sectional view of the light-emitting device 100B shown in Figure 18 along the DD line.

[0134] The light-emitting device 100B has basically the same configuration as the light-emitting device 100A of Example 2. In the light-emitting device 100B of Example 3, the frame 60B is formed in a grid shape so as to surround each of the multiple light-emitting structures 80 arranged in an array on the substrate 10A.

[0135] Furthermore, all components of the light-emitting device 100B, except for the frame 60B, are the same as those used in Example 1. In addition, the raw materials for the frame 60B are the same as those used for the frame 60 in Example 1 and the frame 60A in Example 2.

[0136] Multiple light-emitting element structures 80 are arranged in an array on the upper surface 10AS of the substrate 10A, with predetermined intervals between them. Furthermore, a grid-like frame 60B is integrally formed on the upper surface 10AS of the substrate 10A, individually surrounding each of the arrayed light-emitting element structures 80. In other words, the frame 60B is a structure shared by adjacent light-emitting element structures 80.

[0137] In this way, by enclosing each light-emitting element structure 80 individually with a frame 60B, when separate light-emitting elements 80 are lit individually, it is possible to prevent the light from affecting adjacent light-emitting elements 80 units enclosed by the frame 60B (prevention of crosstalk).

[0138] A light-scattering section 75 is formed between each light-emitting element structure 80 and the frame 60B. The light-scattering section 75 consists of a light-scattering material 75R that integrally covers the surface from the upper end of the side surface of one light-emitting element structure 80 to the upper end of the inner surface of the frame 60B surrounding the one light-emitting element structure 80 and is open at the top, and a concave space CE surrounded by the light-scattering material 75R and open at the top.

[0139] Accordingly, the light scattering material 75R has a first inclined surface 75S1 that slopes downward outward from the upper end of the side surface of each light-emitting element structure 80. The light scattering material 75R also has a flat surface 75S2 that is formed continuously with the first inclined surface 75S1 and extends along the upper surface 10AS of the substrate 10A. The light scattering material 75R also has a second inclined surface 75S3 that is formed continuously with the outer end of the flat surface 75S2 and slopes toward the upper end of the inner surface of the frame 60B surrounding the one light-emitting element structure 80, i.e., slopes upward outward.

[0140] In other words, the light scattering material 75R is formed to have a surface shape similar to that of the light scattering material 70R in Embodiment 1, extending from the upper end of the side surface of one light-emitting element structure 80 to the upper end of the inner surface of the frame 60B surrounding the one light-emitting element structure 80. To put it another way, the light-emitting device 100B has multiple light-emitting element structures 80 consisting of light-emitting elements 20 and wavelength converters 40, light scattering parts 75 and frame 60B arranged in an array on the upper surface 10AS of the substrate 10A.

[0141] Therefore, the light-emitting device 100B of Example 3 can achieve the same effects as the light-emitting device 100 of Example 1, preventing a decrease in the total luminous flux of the light emitted from the light-emitting device 100B and improving the light extraction efficiency.

[0142] In other words, in the light-emitting device 100B of Example 3, the light emitted from the side of the light-emitting element 20 and the light emitted from the side of the wavelength converter 40 are scattered inside the light-scattering material 75R, reach the first inclined surface 75R1, and are emitted into space CD from there, and are radiated upward from the opening of the light-scattering material 70R.

[0143] Furthermore, the light-emitting device 100B of Example 3 can be manufactured using the same manufacturing method as the light-emitting device 100A of Example 2. The differences in the manufacturing method of the light-emitting device 100B compared to the light-emitting device 100A of Example 2 will be explained below.

[0144] As shown in Figure 18, a frame 60B is formed in a grid pattern around the array of multiple light-emitting structures 80 and between each of the multiple light-emitting structures 80 on the upper surface 10AS of the substrate 10A (Step S14 in Figure 5, frame formation step). In this step, first, the raw material resin for the frame 60A is used to draw a grid pattern of the raw material resin for the frame 60A around the array of multiple light-emitting structures 80 and between each of the multiple light-emitting structures 80. Then, the substrate 10A in this state is heated to form the frame 60B.

[0145] Next, the raw resin of the light scattering material 75R is applied between each light-emitting element structure 80 and the frame 60B (step S15 in Figure 5, light scattering resin application step). In this step, the raw resin of the light scattering material 75R is applied between each light-emitting element structure 80 and the frame 60B using a dispenser filled with the raw resin of the light scattering material 75R.

[0146] Next, as shown in Figure 19, the substrate 10A coated with the raw resin of the light scattering material 75R is heated to cure the raw resin of the light scattering material 75R (step S16 in Figure 5, light scattering resin curing step). In this step, the raw resin of the light scattering material 75R is continuously heated to a predetermined temperature in one step, thereby forming a light scattering section 75 having a first inclined surface 75S1, a flat surface 75S2, and a second inclined surface 75S3, and a concave space CE surrounded by each surface and open upwards, between the light-emitting element structure 80 and the frame 60B, respectively.

[0147] Based on the above, the light-emitting device 100B of Example 3 can be manufactured using the same manufacturing method as the light-emitting device 100A of Example 2.

[0148] The embodiments of the present invention have been described above, but these are merely examples and the invention is not limited to these embodiments.

[0149] For example, in Embodiment 1, the frame 60 in each figure has an inner surface that extends perpendicularly to the upper surface 10S of the substrate 10. However, the inner surface of the frame 60 may be formed to slope inward from the upper end, for example. By sloping the inner surface of the frame 60, the inclination angle of the second inclined surface 70S3 of the light-emitting device 100 in Embodiment 1 can be adjusted, and the light distribution characteristics of the light-emitting surface of the light-emitting device 100 can be adjusted. This adjustment of light distribution characteristics is also applicable to Embodiments 2 and 3.

[0150] (modified version) Figure 20 is a cross-sectional view of a modified light-emitting device 100C.

[0151] As shown in Figure 20, in the light-emitting device 100, the wavelength converter 40 may consist of a light-scattering upper layer 40A containing a phosphor (light converter) and a non-scattering, light-transmitting lower layer 40B. This structure increases the light-guiding thickness of light LM1 and light LM2, brightening the light LM6 emitted from space CA and dimming the light LM5 emitted from the upper surface 40T of the wavelength converter 40. In this case, the lower edge of the wavelength converter 40 is the interface between the upper layer 40A and the lower layer 40B. The light-transmitting lower layer is also included in the growth substrate 21. In other words, in this case, the height of the flat surface 70S2 of the light-scattering portion 70 should be lower than the lower surface of the upper layer 40A. This two-layer wavelength converter 40 can be formed by molding the upper layer 40A and the lower layer 40B as two layers, or by bonding them together.

[0152] Thus, the embodiments described are not intended to limit the scope of the invention. The embodiments described can be carried out in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These modifications are also included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0153] 100 Light-emitting devices 10 circuit boards 15 First electrode 17. Second electrode 20 Light-emitting elements 21 Growth substrate 23 Semiconductor structural layer 25 Cathode electrodes 27 Anode electrode 30 element junction layer 40 wavelength converter 50 Adhesive layer 60 Frame 70, 73, 75 Light scattering section

Claims

1. A plate-shaped substrate and A light-emitting element comprising a semiconductor structural layer disposed on the main surface of the substrate and including a light-emitting layer, and a plate-shaped, light-transmitting substrate disposed on the semiconductor structural layer, A wavelength converter containing phosphor particles, disposed on the upper surface of the translucent substrate via an adhesive resin, The light-scattering material comprises a resin material containing light-scattering particles, and is formed to cover the side surface of the wavelength converter, the side surface of the light-emitting element, and the main surface of the substrate. The light scattering material has a first inclined surface that slopes downward outward from the upper end of the side surface of the wavelength converter, a flat surface formed continuously with the first inclined surface and extending along the main surface of the first, and a second inclined surface formed continuously with the outer end of the flat surface and sloping upward outward. The substrate comprises a frame formed on the main surface 1 in contact with the outside of the light scattering material, The height position of the flat surface of the substrate from the main surface 1 is at a position half the thickness of the translucent substrate from the upper surface of the translucent substrate, or lower than that. A light-emitting device characterized in that at least a portion of the light that enters the light-scattering material from the side surface of the translucent substrate and passes through the first inclined surface is reflected by the flat surface.

2. The light-emitting device according to claim 1, characterized in that, in a top view of the light-emitting device, the outer edge of the upper surface of the wavelength converter and the outer edge of the upper surface of the light-emitting element substantially coincide.

3. The light-emitting device according to claim 1 or 2, characterized in that the area of ​​the light-scattering portion formed by the light-scattering material covering the main surface of the substrate, as viewed from above, is 4 times or more and 12 times or less the area of ​​the upper surface of the wavelength converter.

4. The light-emitting device according to any one of claims 1 to 3, characterized in that, in a top view of the light-emitting device, the external shape of the light-scattering portion formed by the light-scattering material covering the main surface 1 of the substrate is a similarly enlarged version of the external shape of the upper surface of the light-emitting element.

5. The light-emitting device according to any one of claims 1 to 4, characterized in that the wavelength converter is a light-scattering ceramic polycrystalline body obtained by mixing and firing the phosphor particles and ceramic particles.

6. The aforementioned light-scattering particles consist of titanium dioxide. The light-emitting device according to any one of claims 1 to 5, characterized in that the light-scattering material is made of a translucent resin in which the light-scattering particles are dispersed at a content of 8 to 30 wt%.

7. The light-emitting device according to any one of claims 1 to 6, characterized in that the height position of the substrate at the upper end of the frame from the main surface of claim 1 is at a height position equal to or greater than the upper surface of the wavelength converter.

8. The light-emitting device according to any one of claims 1 to 7, characterized in that the light-emitting element, the wavelength converter, the light-scattering material, and the frame are arranged in an array on the main surface of the substrate.

9. A plate-shaped substrate and A plurality of light-emitting structures are arranged in an array on the main surface of the substrate, each having a semiconductor structural layer including a light-emitting layer disposed on the main surface of the substrate, a translucent substrate in the shape of a plate and having light-transmitting properties disposed on the semiconductor structural layer, and a wavelength converter each containing phosphor particles, each disposed on the upper surface of the translucent substrate via an adhesive resin, A light-scattering material made of a resin material containing light-scattering particles, formed to cover from the side surface of one of the plurality of light-emitting structures to the side surfaces of other light-emitting structures arranged adjacent to that one light-emitting structure, The substrate comprises a frame formed on the main surface 1 such that it collectively surrounds the plurality of light-emitting structures and is in contact with the outside of the light-scattering material, The light scattering material comprises a first inclined surface that slopes downward outward from the upper end of the side surface of the first light-emitting element structure, a flat surface formed continuously with the first inclined surface and extending along the main surface of the first, and a second inclined surface formed continuously with the outer end of the flat surface and sloping upward toward the upper end of the side surface of the other light-emitting element structure or the inner surface of the frame that faces the side surface of the first light-emitting element structure. It has, The height position of the flat surface of the substrate from the main surface 1 is at a position half the thickness of the translucent substrate from the upper surface of the translucent substrate, or lower than that. A light-emitting device characterized in that at least a portion of the light that enters the light-scattering material from the side surface of the translucent substrate and passes through the first inclined surface is reflected by the flat surface.

10. A method for manufacturing a light-emitting device, The process of preparing a plate-shaped substrate, A device bonding step of bonding a light-emitting element, which includes a semiconductor structural layer containing a light-emitting layer and a translucent substrate in the shape of a plate and having light-transmitting properties disposed on the semiconductor structural layer, to one main surface of the substrate, A wavelength converter bonding step involves bonding a wavelength converter containing phosphor particles to the upper surface of the translucent substrate via an adhesive resin, A frame formation step is to form a frame surrounding the light-emitting element on the main surface 1 of the substrate, A light-scattering resin coating step involves coating the main surface of the substrate with a thermosetting light-scattering resin containing light-scattering particles, The process includes a resin curing step of heating the light scattering resin to form a light scattering material that covers from the side surface of the wavelength converter to the side surface of the light-emitting element and the main surface of the substrate, In the aforementioned resin curing process, The light-scattering resin is continuously heated to a predetermined temperature in one step to form the light-scattering material having a first inclined surface that slopes downward outward from the upper end of the side surface of the wavelength converter, a flat surface that is formed continuously with the first inclined surface and extends along the main surface of the first, and a second inclined surface that is formed continuously with the outer end of the flat surface and slopes upward outward, and A method for manufacturing a light-emitting device, characterized in that the light-scattering material is formed such that the height position of the flat surface of the substrate from the main surface of the substrate is at a position half the thickness of the translucent substrate or lower than that, from the upper surface of the translucent substrate.

11. In the light scattering resin coating step, the light scattering resin is coated on the inner surface of the frame in such a manner that it does not reach the upper end of the inner surface of the frame, The method for manufacturing a light-emitting device according to claim 10, characterized in that, in the resin curing step, the light-scattering resin creeps up to the upper end of the inner surface of the frame.

Images